[v7,8/8] tpm: Added support for TPM emulator

Commit Message

Amarnath Valluri Sept. 22, 2017, 12:33 p.m. UTC

This change introduces a new TPM backend driver that can communicate with
swtpm(software TPM emulator) using unix domain socket interface. QEMU talks to
TPM emulator using socket based chardev backend device.

Swtpm uses two Unix sockets for communications, one for plain TPM commands and
responses, and one for out-of-band control messages. QEMU passes data socket
been used over the control channel.

The swtpm and associated tools can be found here:
    https://github.com/stefanberger/swtpm

The swtpm's control channel protocol specification can be found here:
    https://github.com/stefanberger/swtpm/wiki/Control-Channel-Specification

Usage:
    # setup TPM state directory
    mkdir /tmp/mytpm
    chown -R tss:root /tmp/mytpm
    /usr/bin/swtpm_setup --tpm-state /tmp/mytpm --createek

    # Ask qemu to use TPM emulator with given tpm state directory
    qemu-system-x86_64 \
        [...] \
        -chardev socket,id=chrtpm,path=/tmp/swtpm-sock \
        -tpmdev emulator,id=tpm0,chardev=chrtpm \
        -device tpm-tis,tpmdev=tpm0 \
        [...]

Signed-off-by: Amarnath Valluri <[e-mail]>
---
 configure             |  15 +-
 hmp.c                 |   5 +
 hw/tpm/Makefile.objs  |   1 +
 hw/tpm/tpm_emulator.c | 649 ++++++++++++++++++++++++++++++++++++++++++++++++++
 hw/tpm/tpm_ioctl.h    | 246 +++++++++++++++++++
 qapi/tpm.json         |  21 +-
 qemu-options.hx       |  22 +-
 7 files changed, 950 insertions(+), 9 deletions(-)
 create mode 100644 hw/tpm/tpm_emulator.c
 create mode 100644 hw/tpm/tpm_ioctl.h

Comments

Stefan Berger Sept. 22, 2017, 4:23 p.m. UTC | #1

On 09/22/2017 08:33 AM, Amarnath Valluri wrote:
> This change introduces a new TPM backend driver that can communicate with
> swtpm(software TPM emulator) using unix domain socket interface. QEMU talks to
> TPM emulator using socket based chardev backend device.

talks to the TPM emulator using QEMU's socket-based chardev backend device.

>
> Swtpm uses two Unix sockets for communications, one for plain TPM commands and
> responses, and one for out-of-band control messages. QEMU passes data socket
> been used over the control channel.

QEMU passes the data socket to be used over the control channel.

Some comments below. I'll give it a try once we merge the fd passing 
into swtpm.


>
> The swtpm and associated tools can be found here:
>      https://github.com/stefanberger/swtpm
>
> The swtpm's control channel protocol specification can be found here:
>      https://github.com/stefanberger/swtpm/wiki/Control-Channel-Specification
>
> Usage:
>      # setup TPM state directory
>      mkdir /tmp/mytpm
>      chown -R tss:root /tmp/mytpm
>      /usr/bin/swtpm_setup --tpm-state /tmp/mytpm --createek
>
>      # Ask qemu to use TPM emulator with given tpm state directory
>      qemu-system-x86_64 \
>          [...] \
>          -chardev socket,id=chrtpm,path=/tmp/swtpm-sock \
>          -tpmdev emulator,id=tpm0,chardev=chrtpm \
>          -device tpm-tis,tpmdev=tpm0 \
>          [...]
>
> Signed-off-by: Amarnath Valluri <[e-mail]>
> ---
>   configure             |  15 +-
>   hmp.c                 |   5 +
>   hw/tpm/Makefile.objs  |   1 +
>   hw/tpm/tpm_emulator.c | 649 ++++++++++++++++++++++++++++++++++++++++++++++++++
>   hw/tpm/tpm_ioctl.h    | 246 +++++++++++++++++++
>   qapi/tpm.json         |  21 +-
>   qemu-options.hx       |  22 +-
>   7 files changed, 950 insertions(+), 9 deletions(-)
>   create mode 100644 hw/tpm/tpm_emulator.c
>   create mode 100644 hw/tpm/tpm_ioctl.h
>
> diff --git a/configure b/configure
> index cb0f7ed..ce2df2d 100755
> --- a/configure
> +++ b/configure
> @@ -3461,10 +3461,15 @@ fi
>   ##########################################
>   # TPM passthrough is only on x86 Linux
>
> -if test "$targetos" = Linux && test "$cpu" = i386 -o "$cpu" = x86_64; then
> -  tpm_passthrough=$tpm
> +if test "$targetos" = Linux; then
> +  tpm_emulator=$tpm
> +  if test "$cpu" = i386 -o "$cpu" = x86_64; then
> +    tpm_passthrough=$tpm
> +  else
> +    tpm_passthrough=no
> +  fi
>   else
> -  tpm_passthrough=no
> +  tpm_emulator=no
>   fi
>
>   ##########################################
> @@ -5359,6 +5364,7 @@ echo "gcov enabled      $gcov"
>   echo "TPM support       $tpm"
>   echo "libssh2 support   $libssh2"
>   echo "TPM passthrough   $tpm_passthrough"
> +echo "TPM emulator      $tpm_emulator"
>   echo "QOM debugging     $qom_cast_debug"
>   echo "Live block migration $live_block_migration"
>   echo "lzo support       $lzo"
> @@ -5943,6 +5949,9 @@ if test "$tpm" = "yes"; then
>     if test "$tpm_passthrough" = "yes"; then
>       echo "CONFIG_TPM_PASSTHROUGH=y" >> $config_host_mak
>     fi
> +  if test "$tpm_emulator" = "yes"; then
> +    echo "CONFIG_TPM_EMULATOR=y" >> $config_host_mak
> +  fi
>   fi
>
>   echo "TRACE_BACKENDS=$trace_backends" >> $config_host_mak
> diff --git a/hmp.c b/hmp.c
> index cf62b2e..7e69eca 100644
> --- a/hmp.c
> +++ b/hmp.c
> @@ -995,6 +995,7 @@ void hmp_info_tpm(Monitor *mon, const QDict *qdict)
>       Error *err = NULL;
>       unsigned int c = 0;
>       TPMPassthroughOptions *tpo;
> +    TPMEmulatorOptions *teo;
>
>       info_list = qmp_query_tpm(&err);
>       if (err) {
> @@ -1024,6 +1025,10 @@ void hmp_info_tpm(Monitor *mon, const QDict *qdict)
>                              tpo->has_cancel_path ? ",cancel-path=" : "",
>                              tpo->has_cancel_path ? tpo->cancel_path : "");
>               break;
> +        case TPM_TYPE_EMULATOR:
> +            teo = ti->options->u.emulator.data;
> +            monitor_printf(mon, ",chardev=%s", teo->chardev);
> +            break;
>           case TPM_TYPE__MAX:
>               break;
>           }
> diff --git a/hw/tpm/Makefile.objs b/hw/tpm/Makefile.objs
> index 64cecc3..41f0b7a 100644
> --- a/hw/tpm/Makefile.objs
> +++ b/hw/tpm/Makefile.objs
> @@ -1,2 +1,3 @@
>   common-obj-$(CONFIG_TPM_TIS) += tpm_tis.o
>   common-obj-$(CONFIG_TPM_PASSTHROUGH) += tpm_passthrough.o tpm_util.o
> +common-obj-$(CONFIG_TPM_EMULATOR) += tpm_emulator.o tpm_util.o
> diff --git a/hw/tpm/tpm_emulator.c b/hw/tpm/tpm_emulator.c
> new file mode 100644
> index 0000000..c02bbe2
> --- /dev/null
> +++ b/hw/tpm/tpm_emulator.c
> @@ -0,0 +1,649 @@
> +/*
> + *  emulator TPM driver

Emulator

> + *
> + *  Copyright (c) 2017 Intel Corporation
> + *  Author: Amarnath Valluri <[e-mail]>
> + *
> + *  Copyright (c) 2010 - 2013 IBM Corporation
> + *  Authors:
> + *    Stefan Berger <[e-mail]>
> + *
> + *  Copyright (C) 2011 IAIK, Graz University of Technology
> + *    Author: Andreas Niederl
> + *
> + * This library is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU Lesser General Public
> + * License as published by the Free Software Foundation; either
> + * version 2 of the License, or (at your option) any later version.
> + *
> + * This library is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> + * Lesser General Public License for more details.
> + *
> + * You should have received a copy of the GNU Lesser General Public
> + * License along with this library; if not, see <http://www.gnu.org/licenses/>
> + *
> + */
> +
> +#include "qemu/osdep.h"
> +#include "qemu/error-report.h"
> +#include "qemu/sockets.h"
> +#include "io/channel-socket.h"
> +#include "sysemu/tpm_backend.h"
> +#include "tpm_int.h"
> +#include "hw/hw.h"
> +#include "hw/i386/pc.h"
> +#include "tpm_util.h"
> +#include "tpm_ioctl.h"
> +#include "migration/blocker.h"
> +#include "qapi/error.h"
> +#include "chardev/char-fe.h"
> +
> +#include <fcntl.h>
> +#include <sys/types.h>
> +#include <sys/stat.h>
> +#include <stdio.h>
> +
> +#define DEBUG_TPM 0
> +
> +#define DPRINT(fmt, ...) do { \
> +    if (DEBUG_TPM) { \
> +        fprintf(stderr, fmt, ## __VA_ARGS__); \
> +    } \
> +} while (0);
> +
> +#define DPRINTF(fmt, ...) DPRINT("tpm-emulator: "fmt"\n", __VA_ARGS__)
> +
> +#define TYPE_TPM_EMULATOR "tpm-emulator"
> +#define TPM_EMULATOR(obj) \
> +    OBJECT_CHECK(TPMEmulator, (obj), TYPE_TPM_EMULATOR)
> +
> +#define TPM_EMULATOR_IMPLEMENTS_ALL_CAPS(S, cap) (((S)->caps & (cap)) == (cap))
> +
> +static const TPMDriverOps tpm_emulator_driver;
> +
> +/* data structures */
> +typedef struct TPMEmulator {
> +    TPMBackend parent;
> +
> +    TPMEmulatorOptions *options;
> +    CharBackend ctrl_dev;
> +    QIOChannel *data_ioc;
> +    bool op_executing;
> +    bool op_canceled;
> +    bool had_startup_error;
> +    TPMVersion tpm_version;
> +    ptm_cap caps; /* capabilities of the TPM */
> +    uint8_t cur_locty_number; /* last set locality */
> +    QemuMutex state_lock;
> +    Error *migration_blocker;
> +} TPMEmulator;
> +
> +
> +static int tpm_emulator_ctrlcmd(CharBackend *dev, unsigned long cmd, void *msg,
> +                                size_t msg_len_in, size_t msg_len_out)
> +{
> +    uint32_t cmd_no = cpu_to_be32(cmd);
> +    ssize_t n = sizeof(uint32_t) + msg_len_in;
> +    uint8_t *buf = NULL;
> +
> +    buf = (uint8_t *)malloc(n);
> +    memcpy(buf, &cmd_no, sizeof(cmd_no));
> +    memcpy(buf + sizeof(cmd_no), msg, msg_len_in);
> +
> +    n += qemu_chr_fe_write_all(dev, (const uint8_t *)buf, n);
> +    free(buf);
> +
> +    if (n > 0) {
> +        if (msg_len_out > 0) {
> +            n = qemu_chr_fe_read_all(dev, (uint8_t *)msg, msg_len_out);
> +            /* simulate ioctl return value */
> +            if (n > 0) {
> +                n = 0;
> +            }
> +        } else {
> +            n = 0;
> +        }
> +    }
> +    return n;
> +}
> +
> +static int tpm_emulator_unix_tx_bufs(TPMEmulator *tpm_pt,
> +                                     const uint8_t *in, uint32_t in_len,
> +                                     uint8_t *out, uint32_t out_len,
> +                                     bool *selftest_done)
> +{
> +    ssize_t ret;
> +    bool is_selftest = false;
> +    const struct tpm_resp_hdr *hdr = NULL;
> +    Error *err = NULL;
> +
> +    tpm_pt->op_canceled = false;
> +    tpm_pt->op_executing = true;

add an empty line after the above

> +    if (selftest_done) {
> +        *selftest_done = false;
> +        is_selftest = tpm_util_is_selftest(in, in_len);
> +    }
> +
> +    ret = qio_channel_write(tpm_pt->data_ioc, (char *)in, in_len, &err);
> +    if (ret != in_len || err) {
> +        if (!tpm_pt->op_canceled || errno != ECANCELED) {
> +            error_report("tpm-emulator: error while transmitting data "
> +                         "to TPM: %s", err ? error_get_pretty(err) : "");
> +            error_free(err);
> +        }
> +        goto err_exit;
> +    }
> +
> +    tpm_pt->op_executing = false;
> +
> +    ret = qio_channel_read(tpm_pt->data_ioc, (char *)out, out_len, &err);
> +    if (ret < 0 || err) {
> +        if (!tpm_pt->op_canceled || errno != ECANCELED) {
> +            error_report("tpm-emulator: error while reading data from "
> +                         "TPM: %s", err ? error_get_pretty(err) : "");
> +            error_free(err);
> +        }
> +    } else if (ret >= sizeof(*hdr)) {
> +        hdr = (struct tpm_resp_hdr *)out;
> +    }
> +
> +    if (!hdr || be32_to_cpu(hdr->len) != ret) {
> +        error_report("tpm-emulator: received invalid response "
> +                     "packet from TPM with length :%ld", ret);
> +        ret = -1;
> +        goto err_exit;
> +    }
> +
> +    if (is_selftest) {
> +        *selftest_done = (be32_to_cpu(hdr->errcode) == 0);
> +    }
> +
> +    return 0;
> +
> +err_exit:
> +    if (ret < 0) {
> +        tpm_util_write_fatal_error_response(out, out_len);
> +    }
> +
> +    tpm_pt->op_executing = false;
> +
> +    return ret;
> +}
> +
> +static int tpm_emulator_set_locality(TPMEmulator *tpm_pt, uint8_t locty_number)
> +{
> +    ptm_loc loc;
> +
> +    DPRINTF("%s : locality: 0x%x", __func__, locty_number);
> +
> +    if (tpm_pt->cur_locty_number != locty_number) {
> +        DPRINTF("setting locality : 0x%x", locty_number);
> +        loc.u.req.loc = locty_number;
> +        if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_SET_LOCALITY, &loc,
> +                             sizeof(loc), sizeof(loc)) < 0) {
> +            error_report("tpm-emulator: could not set locality : %s",
> +                         strerror(errno));
> +            return -1;
> +        }
> +        loc.u.resp.tpm_result = be32_to_cpu(loc.u.resp.tpm_result);
> +        if (loc.u.resp.tpm_result != 0) {
> +            error_report("tpm-emulator: TPM result for set locality : 0x%x",
> +                         loc.u.resp.tpm_result);
> +            return -1;
> +        }
> +        tpm_pt->cur_locty_number = locty_number;
> +    }
> +    return 0;
> +}
> +
> +static void tpm_emulator_handle_request(TPMBackend *tb, TPMBackendCmd cmd)
> +{
> +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
> +    TPMLocality *locty = NULL;
> +    bool selftest_done = false;
> +
> +    DPRINTF("processing command type %d", cmd);
> +
> +    switch (cmd) {
> +    case TPM_BACKEND_CMD_PROCESS_CMD:
> +        qemu_mutex_lock(&tpm_pt->state_lock);
> +        locty = tb->tpm_state->locty_data;
> +        if (tpm_emulator_set_locality(tpm_pt,
> +                                      tb->tpm_state->locty_number) < 0) {
> +            tpm_util_write_fatal_error_response(locty->r_buffer.buffer,
> +                                           locty->r_buffer.size);
> +        } else {
> +            tpm_emulator_unix_tx_bufs(tpm_pt, locty->w_buffer.buffer,
> +                                              locty->w_offset,
> +                                              locty->r_buffer.buffer,
> +                                              locty->r_buffer.size,
> +                                              &selftest_done);
> +        }
> +
> +        tb->recv_data_callback(tb->tpm_state, tb->tpm_state->locty_number,
> +                               selftest_done);
> +        qemu_mutex_unlock(&tpm_pt->state_lock);
> +
> +        break;
> +    case TPM_BACKEND_CMD_INIT:
> +    case TPM_BACKEND_CMD_END:
> +    case TPM_BACKEND_CMD_TPM_RESET:
> +        /* nothing to do */
> +        break;
> +    }
> +}
> +
> +/*
> + * Gracefully shut down the external unixio TPM
> + */
> +static void tpm_emulator_shutdown(TPMEmulator *tpm_pt)
> +{
> +    ptm_res res;
> +
> +    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_SHUTDOWN, &res, 0,
> +                         sizeof(res)) < 0) {
> +        error_report("tpm-emulator: Could not cleanly shutdown the TPM: %s",
> +                     strerror(errno));
> +    } else if (res != 0) {
> +        error_report("tpm-emulator: TPM result for sutdown: 0x%x",
> +                     be32_to_cpu(res));
> +    }
> +}
> +
> +static int tpm_emulator_probe_caps(TPMEmulator *tpm_pt)
> +{
> +    DPRINTF("%s", __func__);
> +    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_GET_CAPABILITY,
> +                         &tpm_pt->caps, 0, sizeof(tpm_pt->caps)) < 0) {
> +        error_report("tpm-emulator: probing failed : %s", strerror(errno));
> +        return -1;
> +    }
> +
> +    tpm_pt->caps = be64_to_cpu(tpm_pt->caps);
> +
> +    DPRINTF("capbilities : 0x%lx", tpm_pt->caps);
> +
> +    return 0;
> +}
> +
> +static int tpm_emulator_check_caps(TPMEmulator *tpm_pt)
> +{
> +    ptm_cap caps = 0;
> +    const char *tpm = NULL;
> +
> +    /* check for min. required capabilities */
> +    switch (tpm_pt->tpm_version) {
> +    case TPM_VERSION_1_2:
> +        caps = PTM_CAP_INIT | PTM_CAP_SHUTDOWN | PTM_CAP_GET_TPMESTABLISHED |
> +               PTM_CAP_SET_LOCALITY;
> +        tpm = "1.2";
> +        break;
> +    case TPM_VERSION_2_0:
> +        caps = PTM_CAP_INIT | PTM_CAP_SHUTDOWN | PTM_CAP_GET_TPMESTABLISHED |
> +               PTM_CAP_SET_LOCALITY | PTM_CAP_RESET_TPMESTABLISHED;

Since you are passing the data channel file descriptor via the new 
command, you should be checking for that new command here as well. Add 
it to both 'caps'.

> +        tpm = "2";
> +        break;
> +    case TPM_VERSION_UNSPEC:
> +        error_report("tpm-emulator: TPM version has not been set");
> +        return -1;
> +    }
> +
> +    if (!TPM_EMULATOR_IMPLEMENTS_ALL_CAPS(tpm_pt, caps)) {
> +        error_report("tpm-emulator: TPM does not implement minimum set of "
> +                     "required capabilities for TPM %s (0x%x)", tpm, (int)caps);
> +        return -1;
> +    }
> +
> +    return 0;
> +}
> +
> +static int tpm_emulator_startup_tpm(TPMBackend *tb)
> +{
> +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
> +    ptm_init init;
> +    ptm_res res;
> +
> +    DPRINTF("%s", __func__);
> +    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_INIT, &init, sizeof(init),
> +                         sizeof(init)) < 0) {
> +        error_report("tpm-emulator: could not send INIT: %s",
> +                     strerror(errno));
> +        goto err_exit;
> +    }
> +
> +    res = be32_to_cpu(init.u.resp.tpm_result);
> +    if (res) {
> +        error_report("tpm-emulator: TPM result for CMD_INIT: 0x%x", res);
> +        goto err_exit;
> +    }
> +    return 0;
> +
> +err_exit:
> +    tpm_pt->had_startup_error = true;
> +    return -1;
> +}
> +
> +static bool tpm_emulator_get_tpm_established_flag(TPMBackend *tb)
> +{
> +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
> +    ptm_est est;
> +
> +    DPRINTF("%s", __func__);
> +    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_GET_TPMESTABLISHED, &est, 0,
> +                         sizeof(est)) < 0) {
> +        error_report("tpm-emulator: Could not get the TPM established flag: %s",
> +                     strerror(errno));
> +        return false;
> +    }
> +    DPRINTF("established flag: %0x", est.u.resp.bit);
> +
> +    return (est.u.resp.bit != 0);
> +}
> +
> +static int tpm_emulator_reset_tpm_established_flag(TPMBackend *tb,
> +                                                   uint8_t locty)
> +{
> +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
> +    ptm_reset_est reset_est;
> +    ptm_res res;
> +
> +    /* only a TPM 2.0 will support this */
> +    if (tpm_pt->tpm_version == TPM_VERSION_2_0) {
> +        reset_est.u.req.loc = tpm_pt->cur_locty_number;
> +
> +        if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_RESET_TPMESTABLISHED,
> +                                 &reset_est, sizeof(reset_est),
> +                                 sizeof(reset_est)) < 0) {
> +            error_report("tpm-emulator: Could not reset the establishment bit: "
> +                          "%s", strerror(errno));
> +            return -1;
> +        }
> +
> +        res = be32_to_cpu(reset_est.u.resp.tpm_result);
> +        if (res) {
> +            error_report("tpm-emulator: TPM result for rest establixhed flag: "
> +                         "0x%x", res);
> +            return -1;
> +        }
> +    }
> +
> +    return 0;
> +}
> +
> +static bool tpm_emulator_had_startup_error(TPMBackend *tb)
> +{
> +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
> +
> +    return tpm_pt->had_startup_error;
> +}
> +
> +static void tpm_emulator_cancel_cmd(TPMBackend *tb)
> +{
> +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
> +    ptm_res res;
> +
> +    /*
> +     * As of Linux 3.7 the tpm_tis driver does not properly cancel
> +     * commands on all TPM manufacturers' TPMs.
> +     * Only cancel if we're busy so we don't cancel someone else's
> +     * command, e.g., a command executed on the host.
> +     */
> +    if (tpm_pt->op_executing) {
> +        if (TPM_EMULATOR_IMPLEMENTS_ALL_CAPS(tpm_pt, PTM_CAP_CANCEL_TPM_CMD)) {
> +            if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_CANCEL_TPM_CMD,
> +                                     &res, 0, sizeof(res)) < 0) {
> +                error_report("tpm-emulator: Could not cancel command: %s",
> +                             strerror(errno));
> +            } else if (res != 0) {
> +                error_report("tpm-emulator: Failed to cancel TPM: 0x%x",
> +                             be32_to_cpu(res));
> +            } else {
> +                tpm_pt->op_canceled = true;
> +            }
> +        }
> +    }
> +}
> +
> +static void tpm_emulator_reset(TPMBackend *tb)
> +{
> +    DPRINTF("%s", __func__);
> +
> +    tpm_emulator_cancel_cmd(tb);
> +}
> +
> +static TPMVersion tpm_emulator_get_tpm_version(TPMBackend *tb)
> +{
> +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
> +
> +    return tpm_pt->tpm_version;
> +}
> +
> +static void tpm_emulator_block_migration(TPMEmulator *tpm_pt)
> +{
> +    Error *err = NULL;
> +
> +    error_setg(&tpm_pt->migration_blocker,
> +               "Migration disabled: TPM emulator not yet migratable");
> +    migrate_add_blocker(tpm_pt->migration_blocker, &err);
> +    if (err) {
> +        error_free(err);
> +        error_free(tpm_pt->migration_blocker);
> +        tpm_pt->migration_blocker = NULL;
> +    }
> +}
> +
> +static int tpm_emulator_prepare_data_fd(TPMEmulator *tpm_pt)
> +{
> +    ptm_res res;
> +    Error *err = NULL;
> +    int fds[2] = { -1, -1 };
> +
> +    if (socketpair(AF_UNIX, SOCK_SEQPACKET, 0, fds) < 0) {
> +        error_report("tpm-emulator: Failed to create socketpair");
> +        return -1;
> +    }
> +
> +    qemu_chr_fe_set_msgfds(&tpm_pt->ctrl_dev, fds + 1, 1);
> +
> +    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_SET_DATAFD, &res, 0,
> +                    sizeof(res)) || res != 0) {
> +        error_report("tpm-emulator: Failed to send CMD_SET_DATAFD: %s",
> +                     strerror(errno));
> +        goto err_exit;
> +    }
> +
> +    tpm_pt->data_ioc = QIO_CHANNEL(qio_channel_socket_new_fd(fds[0], &err));
> +    if (err) {
> +        error_report("tpm-emulator: Failed to create io channel : %s",
> +                       error_get_pretty(err));
> +        error_free(err);
> +        goto err_exit;
> +    }
> +
> +    return 0;
> +
> +err_exit:
> +    closesocket(fds[0]);
> +    closesocket(fds[1]);
> +    return -1;
> +}
> +
> +static int tpm_emulator_handle_device_opts(TPMEmulator *tpm_pt, QemuOpts *opts)
> +{
> +    const char *value;
> +
> +    value = qemu_opt_get(opts, "chardev");
> +    if (value) {
> +        Error *err = NULL;
> +        Chardev *dev = qemu_chr_find(value);
> +
> +        tpm_pt->options->chardev = g_strdup(value);

Could you set this after the error checks?

> +
> +        if (!dev || !qemu_chr_fe_init(&tpm_pt->ctrl_dev, dev, &err)) {
> +            error_report("tpm-emulator: No valid chardev found at '%s': %s",
> +                         value, err ? error_get_pretty(err) : "");
> +            error_free(err);
> +            goto err;
> +        }
> +    }
> +
> +    if (tpm_emulator_prepare_data_fd(tpm_pt) < 0) {
> +        goto err;
> +    }
> +
> +    /* FIXME: tpm_util_test_tpmdev() accepts only on socket fd, as it also used
> +     * by passthrough driver, which not yet using GIOChannel.
> +     */
> +    if (tpm_util_test_tpmdev(QIO_CHANNEL_SOCKET(tpm_pt->data_ioc)->fd,
> +                             &tpm_pt->tpm_version)) {
> +        error_report("'%s' is not emulating TPM device. Error: %s",
> +                      tpm_pt->options->chardev, strerror(errno));
> +        goto err;
> +    }
> +
> +    DPRINTF("TPM Version %s", tpm_pt->tpm_version == TPM_VERSION_1_2 ? "1.2" :
> +             (tpm_pt->tpm_version == TPM_VERSION_2_0 ?  "2.0" : "Unspecified"));
> +
> +    if (tpm_emulator_probe_caps(tpm_pt) ||
> +        tpm_emulator_check_caps(tpm_pt)) {
> +        goto err;
> +    }
> +
> +    tpm_emulator_block_migration(tpm_pt);
> +
> +    return 0;
> +
> +err:
> +    DPRINT("Startup error\n");
> +    return -1;
> +}
> +
> +static TPMBackend *tpm_emulator_create(QemuOpts *opts, const char *id)
> +{
> +    TPMBackend *tb = TPM_BACKEND(object_new(TYPE_TPM_EMULATOR));
> +
> +    tb->id = g_strdup(id);
> +
> +    if (tpm_emulator_handle_device_opts(TPM_EMULATOR(tb), opts)) {
> +        goto err_exit;
> +    }
> +
> +    return tb;
> +
> +err_exit:
> +    object_unref(OBJECT(tb));
> +
> +    return NULL;
> +}
> +
> +static TpmTypeOptions *tpm_emulator_get_tpm_options(TPMBackend *tb)
> +{
> +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
> +    TpmTypeOptions *options = NULL;
> +    TPMEmulatorOptions *eoptions = NULL;
> +
> +    eoptions = g_new0(TPMEmulatorOptions, 1);
> +    if (!eoptions) {
> +        return NULL;
> +    }
> +    DPRINTF("%s", __func__);

You can probably remove this.

> +
> +    eoptions->chardev = g_strdup(tpm_pt->options->chardev);
> +    options = g_new0(TpmTypeOptions, 1);
> +    if (!options) {
> +        qapi_free_TPMEmulatorOptions(eoptions);
> +        return NULL;
> +    }
> +
> +    options->type = TPM_TYPE_EMULATOR;
> +    options->u.emulator.data = eoptions;
> +
> +    return options;
> +}
> +
> +static const QemuOptDesc tpm_emulator_cmdline_opts[] = {
> +    TPM_STANDARD_CMDLINE_OPTS,
> +    {
> +        .name = "chardev",
> +        .type = QEMU_OPT_STRING,
> +        .help = "Character device to use for out-of-band control messages",
> +    },
> +    { /* end of list */ },
> +};
> +
> +static const TPMDriverOps tpm_emulator_driver = {
> +    .type                     = TPM_TYPE_EMULATOR,
> +    .opts                     = tpm_emulator_cmdline_opts,
> +    .desc                     = "TPM emulator backend driver",
> +
> +    .create                   = tpm_emulator_create,
> +    .startup_tpm              = tpm_emulator_startup_tpm,
> +    .reset                    = tpm_emulator_reset,
> +    .had_startup_error        = tpm_emulator_had_startup_error,
> +    .cancel_cmd               = tpm_emulator_cancel_cmd,
> +    .get_tpm_established_flag = tpm_emulator_get_tpm_established_flag,
> +    .reset_tpm_established_flag = tpm_emulator_reset_tpm_established_flag,
> +    .get_tpm_version          = tpm_emulator_get_tpm_version,
> +    .get_tpm_options          = tpm_emulator_get_tpm_options,
> +};
> +
> +static void tpm_emulator_inst_init(Object *obj)
> +{
> +    TPMEmulator *tpm_pt = TPM_EMULATOR(obj);
> +
> +    DPRINTF("%s", __func__);
> +    tpm_pt->options = g_new0(TPMEmulatorOptions, 1);
> +    tpm_pt->op_executing = tpm_pt->op_canceled = false;
> +    tpm_pt->had_startup_error = false;
> +    tpm_pt->cur_locty_number = ~0;
> +    qemu_mutex_init(&tpm_pt->state_lock);
> +}
> +
> +static void tpm_emulator_inst_finalize(Object *obj)
> +{
> +    TPMEmulator *tpm_pt = TPM_EMULATOR(obj);
> +
> +    tpm_emulator_cancel_cmd(TPM_BACKEND(obj));
> +    tpm_emulator_shutdown(tpm_pt);
> +
> +    if (tpm_pt->data_ioc) {
> +        qio_channel_close(tpm_pt->data_ioc, NULL);
> +    }
> +
> +    qemu_chr_fe_deinit(&tpm_pt->ctrl_dev, false);
> +
> +    if (tpm_pt->options) {
> +        qapi_free_TPMEmulatorOptions(tpm_pt->options);
> +    }
> +
> +    if (tpm_pt->migration_blocker) {
> +        migrate_del_blocker(tpm_pt->migration_blocker);
> +        error_free(tpm_pt->migration_blocker);
> +    }
> +}
> +
> +static void tpm_emulator_class_init(ObjectClass *klass, void *data)
> +{
> +    TPMBackendClass *tbc = TPM_BACKEND_CLASS(klass);
> +    tbc->ops = &tpm_emulator_driver;
> +    tbc->handle_request = tpm_emulator_handle_request;
> +}
> +
> +static const TypeInfo tpm_emulator_info = {
> +    .name = TYPE_TPM_EMULATOR,
> +    .parent = TYPE_TPM_BACKEND,
> +    .instance_size = sizeof(TPMEmulator),
> +    .class_init = tpm_emulator_class_init,
> +    .instance_init = tpm_emulator_inst_init,
> +    .instance_finalize = tpm_emulator_inst_finalize,
> +};
> +
> +static void tpm_emulator_register(void)
> +{
> +    type_register_static(&tpm_emulator_info);
> +    tpm_register_driver(&tpm_emulator_driver);
> +}
> +
> +type_init(tpm_emulator_register)
> diff --git a/hw/tpm/tpm_ioctl.h b/hw/tpm/tpm_ioctl.h
> new file mode 100644
> index 0000000..33564b1
> --- /dev/null
> +++ b/hw/tpm/tpm_ioctl.h
> @@ -0,0 +1,246 @@
> +/*
> + * tpm_ioctl.h
> + *
> + * (c) Copyright IBM Corporation 2014, 2015.
> + *
> + * This file is licensed under the terms of the 3-clause BSD license
> + */
> +#ifndef _TPM_IOCTL_H_
> +#define _TPM_IOCTL_H_
> +
> +#include <stdint.h>
> +#include <sys/uio.h>
> +#include <sys/types.h>
> +#include <sys/ioctl.h>
> +
> +/*
> + * Every response from a command involving a TPM command execution must hold
> + * the ptm_res as the first element.
> + * ptm_res corresponds to the error code of a command executed by the TPM.
> + */
> +
> +typedef uint32_t ptm_res;
> +
> +/* PTM_GET_TPMESTABLISHED: get the establishment bit */
> +struct ptm_est {
> +    union {
> +        struct {
> +            ptm_res tpm_result;
> +            unsigned char bit; /* TPM established bit */
> +        } resp; /* response */
> +    } u;
> +};
> +
> +/* PTM_RESET_TPMESTABLISHED: reset establishment bit */
> +struct ptm_reset_est {
> +    union {
> +        struct {
> +            uint8_t loc; /* locality to use */
> +        } req; /* request */
> +        struct {
> +            ptm_res tpm_result;
> +        } resp; /* response */
> +    } u;
> +};
> +
> +/* PTM_INIT */
> +struct ptm_init {
> +    union {
> +        struct {
> +            uint32_t init_flags; /* see definitions below */
> +        } req; /* request */
> +        struct {
> +            ptm_res tpm_result;
> +        } resp; /* response */
> +    } u;
> +};
> +
> +/* above init_flags */
> +#define PTM_INIT_FLAG_DELETE_VOLATILE (1 << 0)
> +    /* delete volatile state file after reading it */
> +
> +/* PTM_SET_LOCALITY */
> +struct ptm_loc {
> +    union {
> +        struct {
> +            uint8_t loc; /* locality to set */
> +        } req; /* request */
> +        struct {
> +            ptm_res tpm_result;
> +        } resp; /* response */
> +    } u;
> +};
> +
> +/* PTM_HASH_DATA: hash given data */
> +struct ptm_hdata {
> +    union {
> +        struct {
> +            uint32_t length;
> +            uint8_t data[4096];
> +        } req; /* request */
> +        struct {
> +            ptm_res tpm_result;
> +        } resp; /* response */
> +    } u;
> +};
> +
> +/*
> + * size of the TPM state blob to transfer; x86_64 can handle 8k,
> + * ppc64le only ~7k; keep the response below a 4k page size
> + */
> +#define PTM_STATE_BLOB_SIZE (3 * 1024)
> +
> +/*
> + * The following is the data structure to get state blobs from the TPM.
> + * If the size of the state blob exceeds the PTM_STATE_BLOB_SIZE, multiple reads
> + * with this ioctl and with adjusted offset are necessary. All bytes
> + * must be transferred and the transfer is done once the last byte has been
> + * returned.
> + * It is possible to use the read() interface for reading the data; however, the
> + * first bytes of the state blob will be part of the response to the ioctl(); a
> + * subsequent read() is only necessary if the total length (totlength) exceeds
> + * the number of received bytes. seek() is not supported.
> + */
> +struct ptm_getstate {
> +    union {
> +        struct {
> +            uint32_t state_flags; /* may be: PTM_STATE_FLAG_DECRYPTED */
> +            uint32_t type;        /* which blob to pull */
> +            uint32_t offset;      /* offset from where to read */
> +        } req; /* request */
> +        struct {
> +            ptm_res tpm_result;
> +            uint32_t state_flags; /* may be: PTM_STATE_FLAG_ENCRYPTED */
> +            uint32_t totlength;   /* total length that will be transferred */
> +            uint32_t length;      /* number of bytes in following buffer */
> +            uint8_t  data[PTM_STATE_BLOB_SIZE];
> +        } resp; /* response */
> +    } u;
> +};
> +
> +/* TPM state blob types */
> +#define PTM_BLOB_TYPE_PERMANENT  1
> +#define PTM_BLOB_TYPE_VOLATILE   2
> +#define PTM_BLOB_TYPE_SAVESTATE  3
> +
> +/* state_flags above : */
> +#define PTM_STATE_FLAG_DECRYPTED     1 /* on input:  get decrypted state */
> +#define PTM_STATE_FLAG_ENCRYPTED     2 /* on output: state is encrypted */
> +
> +/*
> + * The following is the data structure to set state blobs in the TPM.
> + * If the size of the state blob exceeds the PTM_STATE_BLOB_SIZE, multiple
> + * 'writes' using this ioctl are necessary. The last packet is indicated
> + * by the length being smaller than the PTM_STATE_BLOB_SIZE.
> + * The very first packet may have a length indicator of '0' enabling
> + * a write() with all the bytes from a buffer. If the write() interface
> + * is used, a final ioctl with a non-full buffer must be made to indicate
> + * that all data were transferred (a write with 0 bytes would not work).
> + */
> +struct ptm_setstate {
> +    union {
> +        struct {
> +            uint32_t state_flags; /* may be PTM_STATE_FLAG_ENCRYPTED */
> +            uint32_t type;        /* which blob to set */
> +            uint32_t length;      /* length of the data;
> +                                     use 0 on the first packet to
> +                                     transfer using write() */
> +            uint8_t data[PTM_STATE_BLOB_SIZE];
> +        } req; /* request */
> +        struct {
> +            ptm_res tpm_result;
> +        } resp; /* response */
> +    } u;
> +};
> +
> +/*
> + * PTM_GET_CONFIG: Data structure to get runtime configuration information
> + * such as which keys are applied.
> + */
> +struct ptm_getconfig {
> +    union {
> +        struct {
> +            ptm_res tpm_result;
> +            uint32_t flags;
> +        } resp; /* response */
> +    } u;
> +};
> +
> +#define PTM_CONFIG_FLAG_FILE_KEY        0x1
> +#define PTM_CONFIG_FLAG_MIGRATION_KEY   0x2
> +
> +
> +typedef uint64_t ptm_cap;
> +typedef struct ptm_est ptm_est;
> +typedef struct ptm_reset_est ptm_reset_est;
> +typedef struct ptm_loc ptm_loc;
> +typedef struct ptm_hdata ptm_hdata;
> +typedef struct ptm_init ptm_init;
> +typedef struct ptm_getstate ptm_getstate;
> +typedef struct ptm_setstate ptm_setstate;
> +typedef struct ptm_getconfig ptm_getconfig;
> +
> +/* capability flags returned by PTM_GET_CAPABILITY */
> +#define PTM_CAP_INIT               (1)
> +#define PTM_CAP_SHUTDOWN           (1 << 1)
> +#define PTM_CAP_GET_TPMESTABLISHED (1 << 2)
> +#define PTM_CAP_SET_LOCALITY       (1 << 3)
> +#define PTM_CAP_HASHING            (1 << 4)
> +#define PTM_CAP_CANCEL_TPM_CMD     (1 << 5)
> +#define PTM_CAP_STORE_VOLATILE     (1 << 6)
> +#define PTM_CAP_RESET_TPMESTABLISHED (1 << 7)
> +#define PTM_CAP_GET_STATEBLOB      (1 << 8)
> +#define PTM_CAP_SET_STATEBLOB      (1 << 9)
> +#define PTM_CAP_STOP               (1 << 10)
> +#define PTM_CAP_GET_CONFIG         (1 << 11)
> +#define PTM_CAP_SET_DATAFD         (1 << 12)
> +
> +enum {
> +    PTM_GET_CAPABILITY     = _IOR('P', 0, ptm_cap),
> +    PTM_INIT               = _IOWR('P', 1, ptm_init),
> +    PTM_SHUTDOWN           = _IOR('P', 2, ptm_res),
> +    PTM_GET_TPMESTABLISHED = _IOR('P', 3, ptm_est),
> +    PTM_SET_LOCALITY       = _IOWR('P', 4, ptm_loc),
> +    PTM_HASH_START         = _IOR('P', 5, ptm_res),
> +    PTM_HASH_DATA          = _IOWR('P', 6, ptm_hdata),
> +    PTM_HASH_END           = _IOR('P', 7, ptm_res),
> +    PTM_CANCEL_TPM_CMD     = _IOR('P', 8, ptm_res),
> +    PTM_STORE_VOLATILE     = _IOR('P', 9, ptm_res),
> +    PTM_RESET_TPMESTABLISHED = _IOWR('P', 10, ptm_reset_est),
> +    PTM_GET_STATEBLOB      = _IOWR('P', 11, ptm_getstate),
> +    PTM_SET_STATEBLOB      = _IOWR('P', 12, ptm_setstate),
> +    PTM_STOP               = _IOR('P', 13, ptm_res),
> +    PTM_GET_CONFIG         = _IOR('P', 14, ptm_getconfig),
> +    PTM_SET_DATAFD         = _IOR('P', 15, ptm_res),
> +};
> +
> +/*
> + * Commands used by the non-CUSE TPMs
> + *
> + * All messages container big-endian data.
> + *
> + * The return messages only contain the 'resp' part of the unions
> + * in the data structures above. Besides that the limits in the
> + * buffers above (ptm_hdata:u.req.data and ptm_get_state:u.resp.data
> + * and ptm_set_state:u.req.data) are 0xffffffff.
> + */
> +enum {
> +    CMD_GET_CAPABILITY = 1,
> +    CMD_INIT,
> +    CMD_SHUTDOWN,
> +    CMD_GET_TPMESTABLISHED,
> +    CMD_SET_LOCALITY,
> +    CMD_HASH_START,
> +    CMD_HASH_DATA,
> +    CMD_HASH_END,
> +    CMD_CANCEL_TPM_CMD,
> +    CMD_STORE_VOLATILE,
> +    CMD_RESET_TPMESTABLISHED,
> +    CMD_GET_STATEBLOB,
> +    CMD_SET_STATEBLOB,
> +    CMD_STOP,
> +    CMD_GET_CONFIG,
> +    CMD_SET_DATAFD
> +};
> +
> +#endif /* _TPM_IOCTL_H */
> diff --git a/qapi/tpm.json b/qapi/tpm.json
> index e8b2d8d..7093f26 100644
> --- a/qapi/tpm.json
> +++ b/qapi/tpm.json
> @@ -39,10 +39,12 @@
>   # An enumeration of TPM types
>   #
>   # @passthrough: TPM passthrough type
> +# @emulator: Software Emulator TPM type
> +#            Since: 2.11
>   #
>   # Since: 1.5
>   ##
> -{ 'enum': 'TpmType', 'data': [ 'passthrough' ] }
> +{ 'enum': 'TpmType', 'data': [ 'passthrough', 'emulator' ] }
>
>   ##
>   # @query-tpm-types:
> @@ -56,7 +58,7 @@
>   # Example:
>   #
>   # -> { "execute": "query-tpm-types" }
> -# <- { "return": [ "passthrough" ] }
> +# <- { "return": [ "passthrough", "emulator" ] }
>   #
>   ##
>   { 'command': 'query-tpm-types', 'returns': ['TpmType'] }
> @@ -77,16 +79,29 @@
>                                                '*cancel-path' : 'str'} }
>
>   ##
> +# @TPMEmulatorOptions:
> +#
> +# Information about the TPM emulator type
> +#
> +# @chardev: Name of a unix socket chardev
> +#
> +# Since: 2.11
> +##
> +{ 'struct': 'TPMEmulatorOptions', 'data': { 'chardev' : 'str' } }
> +
> +##
>   # @TpmTypeOptions:
>   #
>   # A union referencing different TPM backend types' configuration options
>   #
>   # @type: 'passthrough' The configuration options for the TPM passthrough type
> +#        'emulator' The configuration options for TPM emulator backend type
>   #
>   # Since: 1.5
>   ##
>   { 'union': 'TpmTypeOptions',
> -   'data': { 'passthrough' : 'TPMPassthroughOptions' } }
> +   'data': { 'passthrough' : 'TPMPassthroughOptions',
> +             'emulator': 'TPMEmulatorOptions' } }
>
>   ##
>   # @TPMInfo:
> diff --git a/qemu-options.hx b/qemu-options.hx
> index 77859a2..1e93e53 100644
> --- a/qemu-options.hx
> +++ b/qemu-options.hx
> @@ -3121,7 +3121,9 @@ DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \
>       "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n"
>       "                use path to provide path to a character device; default is /dev/tpm0\n"
>       "                use cancel-path to provide path to TPM's cancel sysfs entry; if\n"
> -    "                not provided it will be searched for in /sys/class/misc/tpm?/device\n",
> +    "                not provided it will be searched for in /sys/class/misc/tpm?/device\n"
> +    "-tpmdev emulator,id=id,chardev=dev\n"
> +    "                configure the TPM device using chardev backend\n",
>       QEMU_ARCH_ALL)
>   STEXI
>
> @@ -3130,8 +3132,8 @@ The general form of a TPM device option is:
>
>   @item -tpmdev @var{backend} ,id=@var{id} [,@var{options}]
>   @findex -tpmdev
> -Backend type must be:
> -@option{passthrough}.
> +Backend type must be either one of the following:
> +@option{passthrough}, @option{emulator}.
>
>   The specific backend type will determine the applicable options.
>   The @code{-tpmdev} option creates the TPM backend and requires a
> @@ -3181,6 +3183,20 @@ To create a passthrough TPM use the following two options:
>   Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by
>   @code{tpmdev=tpm0} in the device option.
>
> +@item -tpmdev emulator, id=@var{id}, chardev=@var{dev}
> +
> +(Linux-host only) Enable access to a TPM emulator using Unix domain socket based
> +chardev backend.
> +
> +@option{chardev} specifies the unique ID of a character device backend that provides connection to the software TPM server.
> +
> +To create a TPM emulator backend device with chardev socket backend:
> +@example
> +
> +-chardev socket,id=chrtpm,path=/tmp/swtpm-ctrl -tpmdev emulator,id=tpm0,chardev=chrtpm -device tpm-tis,tpmdev=tpm0
> +
> +@end example
> +
>   @end table
>
>   ETEXI



     Stefan

Marc-André Lureau Sept. 24, 2017, 6:52 p.m. UTC | #2

Hi

Thanks for the nice update, removing the exec() code, using chardev
and a private socketpair. Some comments below:

On Fri, Sep 22, 2017 at 2:33 PM, Amarnath Valluri
<[e-mail]> wrote:
> This change introduces a new TPM backend driver that can communicate with
> swtpm(software TPM emulator) using unix domain socket interface. QEMU talks to
> TPM emulator using socket based chardev backend device.
>
> Swtpm uses two Unix sockets for communications, one for plain TPM commands and
> responses, and one for out-of-band control messages. QEMU passes data socket
> been used over the control channel.
>
> The swtpm and associated tools can be found here:
>     https://github.com/stefanberger/swtpm
>
> The swtpm's control channel protocol specification can be found here:
>     https://github.com/stefanberger/swtpm/wiki/Control-Channel-Specification
>
> Usage:
>     # setup TPM state directory
>     mkdir /tmp/mytpm
>     chown -R tss:root /tmp/mytpm
>     /usr/bin/swtpm_setup --tpm-state /tmp/mytpm --createek
>
>     # Ask qemu to use TPM emulator with given tpm state directory
>     qemu-system-x86_64 \
>         [...] \
>         -chardev socket,id=chrtpm,path=/tmp/swtpm-sock \
>         -tpmdev emulator,id=tpm0,chardev=chrtpm \
>         -device tpm-tis,tpmdev=tpm0 \
>         [...]
>
> Signed-off-by: Amarnath Valluri <[e-mail]>
> ---
>  configure             |  15 +-
>  hmp.c                 |   5 +
>  hw/tpm/Makefile.objs  |   1 +
>  hw/tpm/tpm_emulator.c | 649 ++++++++++++++++++++++++++++++++++++++++++++++++++
>  hw/tpm/tpm_ioctl.h    | 246 +++++++++++++++++++
>  qapi/tpm.json         |  21 +-
>  qemu-options.hx       |  22 +-
>  7 files changed, 950 insertions(+), 9 deletions(-)
>  create mode 100644 hw/tpm/tpm_emulator.c
>  create mode 100644 hw/tpm/tpm_ioctl.h
>
> diff --git a/configure b/configure
> index cb0f7ed..ce2df2d 100755
> --- a/configure
> +++ b/configure
> @@ -3461,10 +3461,15 @@ fi
>  ##########################################
>  # TPM passthrough is only on x86 Linux
>
> -if test "$targetos" = Linux && test "$cpu" = i386 -o "$cpu" = x86_64; then
> -  tpm_passthrough=$tpm
> +if test "$targetos" = Linux; then
> +  tpm_emulator=$tpm
> +  if test "$cpu" = i386 -o "$cpu" = x86_64; then
> +    tpm_passthrough=$tpm
> +  else
> +    tpm_passthrough=no
> +  fi
>  else
> -  tpm_passthrough=no
> +  tpm_emulator=no
>  fi
>
>  ##########################################
> @@ -5359,6 +5364,7 @@ echo "gcov enabled      $gcov"
>  echo "TPM support       $tpm"
>  echo "libssh2 support   $libssh2"
>  echo "TPM passthrough   $tpm_passthrough"
> +echo "TPM emulator      $tpm_emulator"
>  echo "QOM debugging     $qom_cast_debug"
>  echo "Live block migration $live_block_migration"
>  echo "lzo support       $lzo"
> @@ -5943,6 +5949,9 @@ if test "$tpm" = "yes"; then
>    if test "$tpm_passthrough" = "yes"; then
>      echo "CONFIG_TPM_PASSTHROUGH=y" >> $config_host_mak
>    fi
> +  if test "$tpm_emulator" = "yes"; then
> +    echo "CONFIG_TPM_EMULATOR=y" >> $config_host_mak

It shouldn't require Linux, but posix (and I assume a port to other
systems isn't impossible). same for build-sys / help / comments.

> +  fi
>  fi
>
>  echo "TRACE_BACKENDS=$trace_backends" >> $config_host_mak
> diff --git a/hmp.c b/hmp.c
> index cf62b2e..7e69eca 100644
> --- a/hmp.c
> +++ b/hmp.c
> @@ -995,6 +995,7 @@ void hmp_info_tpm(Monitor *mon, const QDict *qdict)
>      Error *err = NULL;
>      unsigned int c = 0;
>      TPMPassthroughOptions *tpo;
> +    TPMEmulatorOptions *teo;
>
>      info_list = qmp_query_tpm(&err);
>      if (err) {
> @@ -1024,6 +1025,10 @@ void hmp_info_tpm(Monitor *mon, const QDict *qdict)
>                             tpo->has_cancel_path ? ",cancel-path=" : "",
>                             tpo->has_cancel_path ? tpo->cancel_path : "");
>              break;
> +        case TPM_TYPE_EMULATOR:
> +            teo = ti->options->u.emulator.data;
> +            monitor_printf(mon, ",chardev=%s", teo->chardev);
> +            break;
>          case TPM_TYPE__MAX:
>              break;
>          }
> diff --git a/hw/tpm/Makefile.objs b/hw/tpm/Makefile.objs
> index 64cecc3..41f0b7a 100644
> --- a/hw/tpm/Makefile.objs
> +++ b/hw/tpm/Makefile.objs
> @@ -1,2 +1,3 @@
>  common-obj-$(CONFIG_TPM_TIS) += tpm_tis.o
>  common-obj-$(CONFIG_TPM_PASSTHROUGH) += tpm_passthrough.o tpm_util.o
> +common-obj-$(CONFIG_TPM_EMULATOR) += tpm_emulator.o tpm_util.o
> diff --git a/hw/tpm/tpm_emulator.c b/hw/tpm/tpm_emulator.c
> new file mode 100644
> index 0000000..c02bbe2
> --- /dev/null
> +++ b/hw/tpm/tpm_emulator.c
> @@ -0,0 +1,649 @@
> +/*
> + *  emulator TPM driver
> + *
> + *  Copyright (c) 2017 Intel Corporation
> + *  Author: Amarnath Valluri <[e-mail]>
> + *
> + *  Copyright (c) 2010 - 2013 IBM Corporation
> + *  Authors:
> + *    Stefan Berger <[e-mail]>
> + *
> + *  Copyright (C) 2011 IAIK, Graz University of Technology
> + *    Author: Andreas Niederl
> + *
> + * This library is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU Lesser General Public
> + * License as published by the Free Software Foundation; either
> + * version 2 of the License, or (at your option) any later version.
> + *
> + * This library is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> + * Lesser General Public License for more details.
> + *
> + * You should have received a copy of the GNU Lesser General Public
> + * License along with this library; if not, see <http://www.gnu.org/licenses/>
> + *
> + */
> +
> +#include "qemu/osdep.h"
> +#include "qemu/error-report.h"
> +#include "qemu/sockets.h"
> +#include "io/channel-socket.h"
> +#include "sysemu/tpm_backend.h"
> +#include "tpm_int.h"
> +#include "hw/hw.h"
> +#include "hw/i386/pc.h"
> +#include "tpm_util.h"
> +#include "tpm_ioctl.h"
> +#include "migration/blocker.h"
> +#include "qapi/error.h"
> +#include "chardev/char-fe.h"
> +
> +#include <fcntl.h>
> +#include <sys/types.h>
> +#include <sys/stat.h>
> +#include <stdio.h>
> +
> +#define DEBUG_TPM 0
> +
> +#define DPRINT(fmt, ...) do { \
> +    if (DEBUG_TPM) { \
> +        fprintf(stderr, fmt, ## __VA_ARGS__); \
> +    } \
> +} while (0);
> +
> +#define DPRINTF(fmt, ...) DPRINT("tpm-emulator: "fmt"\n", __VA_ARGS__)

I would define a single DPRINTF() (& drop DPRINT usage below)


> +
> +#define TYPE_TPM_EMULATOR "tpm-emulator"
> +#define TPM_EMULATOR(obj) \
> +    OBJECT_CHECK(TPMEmulator, (obj), TYPE_TPM_EMULATOR)
> +
> +#define TPM_EMULATOR_IMPLEMENTS_ALL_CAPS(S, cap) (((S)->caps & (cap)) == (cap))
> +
> +static const TPMDriverOps tpm_emulator_driver;
> +
> +/* data structures */
> +typedef struct TPMEmulator {
> +    TPMBackend parent;
> +
> +    TPMEmulatorOptions *options;

Contrary to my comment on previous patch, I realize it is convenient
to have a qapi pointer here, so you can use the free visitor later.

> +    CharBackend ctrl_dev;

ctrl_chr perhaps? or just chr or be (the most common name in other devices).

> +    QIOChannel *data_ioc;
> +    bool op_executing;
> +    bool op_canceled;

I think those 2 fields can be dropped, see below.

> +    bool had_startup_error;

I think some little refactoring could remove the whole
had_startup_error() backend & callback before or after the series.
tpm_backend_startup_tpm() already returns an error code.  device or
common backend code could handle & remember that.

> +    TPMVersion tpm_version;

This is probably worth to consider in common code instead, but let's
not worry about it.

> +    ptm_cap caps; /* capabilities of the TPM */
> +    uint8_t cur_locty_number; /* last set locality */
> +    QemuMutex state_lock;
> +    Error *migration_blocker;
> +} TPMEmulator;
> +
> +
> +static int tpm_emulator_ctrlcmd(CharBackend *dev, unsigned long cmd, void *msg,
> +                                size_t msg_len_in, size_t msg_len_out)
> +{
> +    uint32_t cmd_no = cpu_to_be32(cmd);
> +    ssize_t n = sizeof(uint32_t) + msg_len_in;
> +    uint8_t *buf = NULL;
> +
> +    buf = (uint8_t *)malloc(n);

could be g_alloca() instead. Alternatively, why not call 2 write() instead?

none of the casts in this function are necessary, please remove them.

> +    memcpy(buf, &cmd_no, sizeof(cmd_no));
> +    memcpy(buf + sizeof(cmd_no), msg, msg_len_in);
> +
> +    n += qemu_chr_fe_write_all(dev, (const uint8_t *)buf, n);

weird

> +    free(buf);
> +
> +    if (n > 0) {

with the n += above, you'll get interesting behaviour :)

You probably want to check if any write above failed, and return early
for the error case.

Please improve the error handling in this function

> +        if (msg_len_out > 0) {
> +            n = qemu_chr_fe_read_all(dev, (uint8_t *)msg, msg_len_out);
> +            /* simulate ioctl return value */
> +            if (n > 0) {
> +                n = 0;
> +            }
> +        } else {
> +            n = 0;
> +        }
> +    }
> +    return n;
> +}
> +
> +static int tpm_emulator_unix_tx_bufs(TPMEmulator *tpm_pt,

tpm_pt was tpm_passthrough I suppose.

Please rename tpm_pt tpm_emu (or I would suggest "self", but this
isn't common name in qemu code - it's actually common in a close
c-object world., and it is quite convenient...)

> +                                     const uint8_t *in, uint32_t in_len,
> +                                     uint8_t *out, uint32_t out_len,
> +                                     bool *selftest_done)
> +{
> +    ssize_t ret;
> +    bool is_selftest = false;
> +    const struct tpm_resp_hdr *hdr = NULL;
> +    Error *err = NULL;
> +
> +    tpm_pt->op_canceled = false;
> +    tpm_pt->op_executing = true;
> +    if (selftest_done) {
> +        *selftest_done = false;
> +        is_selftest = tpm_util_is_selftest(in, in_len);
> +    }
> +
> +    ret = qio_channel_write(tpm_pt->data_ioc, (char *)in, in_len, &err);

hmm, too bad qio_channel_write() doesn't take a void *

why not write_all()?

> +    if (ret != in_len || err) {
> +        if (!tpm_pt->op_canceled || errno != ECANCELED) {

I don't think ECANCELED make sense for emulator code.

> +            error_report("tpm-emulator: error while transmitting data "
> +                         "to TPM: %s", err ? error_get_pretty(err) : "");
> +            error_free(err);
> +        }
> +        goto err_exit;
> +    }
> +
> +    tpm_pt->op_executing = false;
> +
> +    ret = qio_channel_read(tpm_pt->data_ioc, (char *)out, out_len, &err);
> +    if (ret < 0 || err) {

read_all() ?

> +        if (!tpm_pt->op_canceled || errno != ECANCELED) {
> +            error_report("tpm-emulator: error while reading data from "
> +                         "TPM: %s", err ? error_get_pretty(err) : "");
> +            error_free(err);
> +        }
> +    } else if (ret >= sizeof(*hdr)) {
> +        hdr = (struct tpm_resp_hdr *)out;
> +    }
> +
> +    if (!hdr || be32_to_cpu(hdr->len) != ret) {
> +        error_report("tpm-emulator: received invalid response "
> +                     "packet from TPM with length :%ld", ret);
> +        ret = -1;
> +        goto err_exit;
> +    }
> +
> +    if (is_selftest) {
> +        *selftest_done = (be32_to_cpu(hdr->errcode) == 0);
> +    }
> +
> +    return 0;
> +
> +err_exit:
> +    if (ret < 0) {
> +        tpm_util_write_fatal_error_response(out, out_len);
> +    }
> +
> +    tpm_pt->op_executing = false;
> +
> +    return ret;
> +}
> +
> +static int tpm_emulator_set_locality(TPMEmulator *tpm_pt, uint8_t locty_number)
> +{
> +    ptm_loc loc;
> +
> +    DPRINTF("%s : locality: 0x%x", __func__, locty_number);
> +
> +    if (tpm_pt->cur_locty_number != locty_number) {

return early instead if ==, to avoid code indent etc

> +        DPRINTF("setting locality : 0x%x", locty_number);
> +        loc.u.req.loc = locty_number;

This number isn't set in be like the rest of the protocol?

> +        if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_SET_LOCALITY, &loc,
> +                             sizeof(loc), sizeof(loc)) < 0) {
> +            error_report("tpm-emulator: could not set locality : %s",
> +                         strerror(errno));
> +            return -1;
> +        }
> +        loc.u.resp.tpm_result = be32_to_cpu(loc.u.resp.tpm_result);
> +        if (loc.u.resp.tpm_result != 0) {
> +            error_report("tpm-emulator: TPM result for set locality : 0x%x",
> +                         loc.u.resp.tpm_result);
> +            return -1;
> +        }
> +        tpm_pt->cur_locty_number = locty_number;
> +    }
> +    return 0;
> +}
> +
> +static void tpm_emulator_handle_request(TPMBackend *tb, TPMBackendCmd cmd)
> +{
> +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
> +    TPMLocality *locty = NULL;
> +    bool selftest_done = false;
> +
> +    DPRINTF("processing command type %d", cmd);
> +
> +    switch (cmd) {
> +    case TPM_BACKEND_CMD_PROCESS_CMD:
> +        qemu_mutex_lock(&tpm_pt->state_lock);
> +        locty = tb->tpm_state->locty_data;
> +        if (tpm_emulator_set_locality(tpm_pt,
> +                                      tb->tpm_state->locty_number) < 0) {
> +            tpm_util_write_fatal_error_response(locty->r_buffer.buffer,
> +                                           locty->r_buffer.size);

return / goto here instead of else.

> +        } else {
> +            tpm_emulator_unix_tx_bufs(tpm_pt, locty->w_buffer.buffer,
> +                                              locty->w_offset,
> +                                              locty->r_buffer.buffer,
> +                                              locty->r_buffer.size,
> +                                              &selftest_done);

no error handling?

> +        }
> +
> +        tb->recv_data_callback(tb->tpm_state, tb->tpm_state->locty_number,
> +                               selftest_done);
> +        qemu_mutex_unlock(&tpm_pt->state_lock);
> +
> +        break;
> +    case TPM_BACKEND_CMD_INIT:
> +    case TPM_BACKEND_CMD_END:
> +    case TPM_BACKEND_CMD_TPM_RESET:
> +        /* nothing to do */
> +        break;
> +    }
> +}
> +
> +/*
> + * Gracefully shut down the external unixio TPM
> + */
> +static void tpm_emulator_shutdown(TPMEmulator *tpm_pt)
> +{
> +    ptm_res res;
> +
> +    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_SHUTDOWN, &res, 0,
> +                         sizeof(res)) < 0) {
> +        error_report("tpm-emulator: Could not cleanly shutdown the TPM: %s",
> +                     strerror(errno));
> +    } else if (res != 0) {
> +        error_report("tpm-emulator: TPM result for sutdown: 0x%x",
> +                     be32_to_cpu(res));
> +    }
> +}
> +
> +static int tpm_emulator_probe_caps(TPMEmulator *tpm_pt)
> +{
> +    DPRINTF("%s", __func__);
> +    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_GET_CAPABILITY,
> +                         &tpm_pt->caps, 0, sizeof(tpm_pt->caps)) < 0) {
> +        error_report("tpm-emulator: probing failed : %s", strerror(errno));
> +        return -1;
> +    }
> +
> +    tpm_pt->caps = be64_to_cpu(tpm_pt->caps);
> +
> +    DPRINTF("capbilities : 0x%lx", tpm_pt->caps);
> +
> +    return 0;
> +}
> +
> +static int tpm_emulator_check_caps(TPMEmulator *tpm_pt)
> +{
> +    ptm_cap caps = 0;
> +    const char *tpm = NULL;
> +
> +    /* check for min. required capabilities */
> +    switch (tpm_pt->tpm_version) {
> +    case TPM_VERSION_1_2:
> +        caps = PTM_CAP_INIT | PTM_CAP_SHUTDOWN | PTM_CAP_GET_TPMESTABLISHED |
> +               PTM_CAP_SET_LOCALITY;
> +        tpm = "1.2";
> +        break;
> +    case TPM_VERSION_2_0:
> +        caps = PTM_CAP_INIT | PTM_CAP_SHUTDOWN | PTM_CAP_GET_TPMESTABLISHED |
> +               PTM_CAP_SET_LOCALITY | PTM_CAP_RESET_TPMESTABLISHED;
> +        tpm = "2";
> +        break;
> +    case TPM_VERSION_UNSPEC:
> +        error_report("tpm-emulator: TPM version has not been set");
> +        return -1;
> +    }
> +
> +    if (!TPM_EMULATOR_IMPLEMENTS_ALL_CAPS(tpm_pt, caps)) {
> +        error_report("tpm-emulator: TPM does not implement minimum set of "
> +                     "required capabilities for TPM %s (0x%x)", tpm, (int)caps);
> +        return -1;
> +    }
> +
> +    return 0;
> +}
> +
> +static int tpm_emulator_startup_tpm(TPMBackend *tb)
> +{
> +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
> +    ptm_init init;
> +    ptm_res res;
> +
> +    DPRINTF("%s", __func__);
> +    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_INIT, &init, sizeof(init),
> +                         sizeof(init)) < 0) {
> +        error_report("tpm-emulator: could not send INIT: %s",
> +                     strerror(errno));
> +        goto err_exit;
> +    }
> +
> +    res = be32_to_cpu(init.u.resp.tpm_result);
> +    if (res) {
> +        error_report("tpm-emulator: TPM result for CMD_INIT: 0x%x", res);
> +        goto err_exit;
> +    }
> +    return 0;
> +
> +err_exit:
> +    tpm_pt->had_startup_error = true;
> +    return -1;
> +}
> +
> +static bool tpm_emulator_get_tpm_established_flag(TPMBackend *tb)
> +{
> +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
> +    ptm_est est;
> +
> +    DPRINTF("%s", __func__);
> +    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_GET_TPMESTABLISHED, &est, 0,
> +                         sizeof(est)) < 0) {
> +        error_report("tpm-emulator: Could not get the TPM established flag: %s",
> +                     strerror(errno));
> +        return false;
> +    }
> +    DPRINTF("established flag: %0x", est.u.resp.bit);
> +
> +    return (est.u.resp.bit != 0);
> +}
> +
> +static int tpm_emulator_reset_tpm_established_flag(TPMBackend *tb,
> +                                                   uint8_t locty)
> +{
> +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
> +    ptm_reset_est reset_est;
> +    ptm_res res;
> +
> +    /* only a TPM 2.0 will support this */
> +    if (tpm_pt->tpm_version == TPM_VERSION_2_0) {
> +        reset_est.u.req.loc = tpm_pt->cur_locty_number;
> +
> +        if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_RESET_TPMESTABLISHED,
> +                                 &reset_est, sizeof(reset_est),
> +                                 sizeof(reset_est)) < 0) {
> +            error_report("tpm-emulator: Could not reset the establishment bit: "
> +                          "%s", strerror(errno));
> +            return -1;
> +        }
> +
> +        res = be32_to_cpu(reset_est.u.resp.tpm_result);
> +        if (res) {
> +            error_report("tpm-emulator: TPM result for rest establixhed flag: "
> +                         "0x%x", res);
> +            return -1;
> +        }
> +    }
> +
> +    return 0;
> +}
> +
> +static bool tpm_emulator_had_startup_error(TPMBackend *tb)
> +{
> +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
> +
> +    return tpm_pt->had_startup_error;
> +}
> +
> +static void tpm_emulator_cancel_cmd(TPMBackend *tb)
> +{
> +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
> +    ptm_res res;
> +
> +    /*
> +     * As of Linux 3.7 the tpm_tis driver does not properly cancel
> +     * commands on all TPM manufacturers' TPMs.
> +     * Only cancel if we're busy so we don't cancel someone else's
> +     * command, e.g., a command executed on the host.
> +     */
> +    if (tpm_pt->op_executing) {

The field is set in the worker thread. This is racy. Fortunately this
is not relevant for emulator, I think you can simply drop that check
and the variable. Stefan should confirm though.

> +        if (TPM_EMULATOR_IMPLEMENTS_ALL_CAPS(tpm_pt, PTM_CAP_CANCEL_TPM_CMD)) {
> +            if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_CANCEL_TPM_CMD,
> +                                     &res, 0, sizeof(res)) < 0) {
> +                error_report("tpm-emulator: Could not cancel command: %s",
> +                             strerror(errno));
> +            } else if (res != 0) {
> +                error_report("tpm-emulator: Failed to cancel TPM: 0x%x",
> +                             be32_to_cpu(res));
> +            } else {
> +                tpm_pt->op_canceled = true;
> +            }
> +        }
> +    }
> +}
> +
> +static void tpm_emulator_reset(TPMBackend *tb)
> +{
> +    DPRINTF("%s", __func__);
> +
> +    tpm_emulator_cancel_cmd(tb);
> +}
> +
> +static TPMVersion tpm_emulator_get_tpm_version(TPMBackend *tb)
> +{
> +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
> +
> +    return tpm_pt->tpm_version;
> +}
> +
> +static void tpm_emulator_block_migration(TPMEmulator *tpm_pt)
> +{
> +    Error *err = NULL;
> +
> +    error_setg(&tpm_pt->migration_blocker,
> +               "Migration disabled: TPM emulator not yet migratable");
> +    migrate_add_blocker(tpm_pt->migration_blocker, &err);
> +    if (err) {
> +        error_free(err);

probably better to report_err it instead

> +        error_free(tpm_pt->migration_blocker);
> +        tpm_pt->migration_blocker = NULL;

and return an error code.

> +    }
> +}
> +
> +static int tpm_emulator_prepare_data_fd(TPMEmulator *tpm_pt)
> +{
> +    ptm_res res;
> +    Error *err = NULL;
> +    int fds[2] = { -1, -1 };
> +
> +    if (socketpair(AF_UNIX, SOCK_SEQPACKET, 0, fds) < 0) {
> +        error_report("tpm-emulator: Failed to create socketpair");
> +        return -1;
> +    }
> +
> +    qemu_chr_fe_set_msgfds(&tpm_pt->ctrl_dev, fds + 1, 1);
> +
> +    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_SET_DATAFD, &res, 0,
> +                    sizeof(res)) || res != 0) {

Yay! for making life easier and hiding a protocol detail.

> +        error_report("tpm-emulator: Failed to send CMD_SET_DATAFD: %s",
> +                     strerror(errno));
> +        goto err_exit;
> +    }
> +
> +    tpm_pt->data_ioc = QIO_CHANNEL(qio_channel_socket_new_fd(fds[0], &err));
> +    if (err) {
> +        error_report("tpm-emulator: Failed to create io channel : %s",
> +                       error_get_pretty(err));

error_prepend()?

> +        error_free(err);
> +        goto err_exit;
> +    }

close fds[1] ?

> +
> +    return 0;
> +
> +err_exit:
> +    closesocket(fds[0]);
> +    closesocket(fds[1]);
> +    return -1;
> +}
> +
> +static int tpm_emulator_handle_device_opts(TPMEmulator *tpm_pt, QemuOpts *opts)
> +{
> +    const char *value;
> +
> +    value = qemu_opt_get(opts, "chardev");
> +    if (value) {
> +        Error *err = NULL;
> +        Chardev *dev = qemu_chr_find(value);
> +
> +        tpm_pt->options->chardev = g_strdup(value);
> +
> +        if (!dev || !qemu_chr_fe_init(&tpm_pt->ctrl_dev, dev, &err)) {
> +            error_report("tpm-emulator: No valid chardev found at '%s': %s",
> +                         value, err ? error_get_pretty(err) : "");
> +            error_free(err);

error_prepend

> +            goto err;
> +        }
> +    }
> +
> +    if (tpm_emulator_prepare_data_fd(tpm_pt) < 0) {
> +        goto err;
> +    }
> +
> +    /* FIXME: tpm_util_test_tpmdev() accepts only on socket fd, as it also used
> +     * by passthrough driver, which not yet using GIOChannel.
> +     */
> +    if (tpm_util_test_tpmdev(QIO_CHANNEL_SOCKET(tpm_pt->data_ioc)->fd,
> +                             &tpm_pt->tpm_version)) {
> +        error_report("'%s' is not emulating TPM device. Error: %s",
> +                      tpm_pt->options->chardev, strerror(errno));
> +        goto err;
> +    }
> +
> +    DPRINTF("TPM Version %s", tpm_pt->tpm_version == TPM_VERSION_1_2 ? "1.2" :
> +             (tpm_pt->tpm_version == TPM_VERSION_2_0 ?  "2.0" : "Unspecified"));
> +
> +    if (tpm_emulator_probe_caps(tpm_pt) ||
> +        tpm_emulator_check_caps(tpm_pt)) {
> +        goto err;
> +    }
> +
> +    tpm_emulator_block_migration(tpm_pt);
> +
> +    return 0;
> +
> +err:
> +    DPRINT("Startup error\n");
> +    return -1;
> +}
> +
> +static TPMBackend *tpm_emulator_create(QemuOpts *opts, const char *id)
> +{
> +    TPMBackend *tb = TPM_BACKEND(object_new(TYPE_TPM_EMULATOR));
> +
> +    tb->id = g_strdup(id);
> +
> +    if (tpm_emulator_handle_device_opts(TPM_EMULATOR(tb), opts)) {
> +        goto err_exit;
> +    }
> +
> +    return tb;
> +
> +err_exit:
> +    object_unref(OBJECT(tb));
> +
> +    return NULL;
> +}
> +
> +static TpmTypeOptions *tpm_emulator_get_tpm_options(TPMBackend *tb)
> +{
> +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
> +    TpmTypeOptions *options = NULL;
> +    TPMEmulatorOptions *eoptions = NULL;
> +
> +    eoptions = g_new0(TPMEmulatorOptions, 1);
> +    if (!eoptions) {
> +        return NULL;
> +    }
> +    DPRINTF("%s", __func__);
> +
> +    eoptions->chardev = g_strdup(tpm_pt->options->chardev);
> +    options = g_new0(TpmTypeOptions, 1);
> +    if (!options) {
> +        qapi_free_TPMEmulatorOptions(eoptions);
> +        return NULL;
> +    }
> +
> +    options->type = TPM_TYPE_EMULATOR;
> +    options->u.emulator.data = eoptions;

I think this is a job for QAPI_CLONE.

> +
> +    return options;
> +}
> +
> +static const QemuOptDesc tpm_emulator_cmdline_opts[] = {
> +    TPM_STANDARD_CMDLINE_OPTS,
> +    {
> +        .name = "chardev",
> +        .type = QEMU_OPT_STRING,
> +        .help = "Character device to use for out-of-band control messages",
> +    },
> +    { /* end of list */ },
> +};
> +
> +static const TPMDriverOps tpm_emulator_driver = {
> +    .type                     = TPM_TYPE_EMULATOR,
> +    .opts                     = tpm_emulator_cmdline_opts,
> +    .desc                     = "TPM emulator backend driver",
> +
> +    .create                   = tpm_emulator_create,
> +    .startup_tpm              = tpm_emulator_startup_tpm,
> +    .reset                    = tpm_emulator_reset,
> +    .had_startup_error        = tpm_emulator_had_startup_error,
> +    .cancel_cmd               = tpm_emulator_cancel_cmd,
> +    .get_tpm_established_flag = tpm_emulator_get_tpm_established_flag,
> +    .reset_tpm_established_flag = tpm_emulator_reset_tpm_established_flag,
> +    .get_tpm_version          = tpm_emulator_get_tpm_version,
> +    .get_tpm_options          = tpm_emulator_get_tpm_options,
> +};
> +
> +static void tpm_emulator_inst_init(Object *obj)
> +{
> +    TPMEmulator *tpm_pt = TPM_EMULATOR(obj);
> +
> +    DPRINTF("%s", __func__);
> +    tpm_pt->options = g_new0(TPMEmulatorOptions, 1);
> +    tpm_pt->op_executing = tpm_pt->op_canceled = false;
> +    tpm_pt->had_startup_error = false;
> +    tpm_pt->cur_locty_number = ~0;
> +    qemu_mutex_init(&tpm_pt->state_lock);
> +}
> +
> +static void tpm_emulator_inst_finalize(Object *obj)
> +{
> +    TPMEmulator *tpm_pt = TPM_EMULATOR(obj);
> +
> +    tpm_emulator_cancel_cmd(TPM_BACKEND(obj));
> +    tpm_emulator_shutdown(tpm_pt);
> +
> +    if (tpm_pt->data_ioc) {
> +        qio_channel_close(tpm_pt->data_ioc, NULL);
> +    }
> +
> +    qemu_chr_fe_deinit(&tpm_pt->ctrl_dev, false);
> +
> +    if (tpm_pt->options) {
> +        qapi_free_TPMEmulatorOptions(tpm_pt->options);
> +    }
> +
> +    if (tpm_pt->migration_blocker) {
> +        migrate_del_blocker(tpm_pt->migration_blocker);
> +        error_free(tpm_pt->migration_blocker);
> +    }
> +}
> +
> +static void tpm_emulator_class_init(ObjectClass *klass, void *data)
> +{
> +    TPMBackendClass *tbc = TPM_BACKEND_CLASS(klass);
> +    tbc->ops = &tpm_emulator_driver;
> +    tbc->handle_request = tpm_emulator_handle_request;
> +}
> +
> +static const TypeInfo tpm_emulator_info = {
> +    .name = TYPE_TPM_EMULATOR,
> +    .parent = TYPE_TPM_BACKEND,
> +    .instance_size = sizeof(TPMEmulator),
> +    .class_init = tpm_emulator_class_init,
> +    .instance_init = tpm_emulator_inst_init,
> +    .instance_finalize = tpm_emulator_inst_finalize,
> +};
> +
> +static void tpm_emulator_register(void)
> +{
> +    type_register_static(&tpm_emulator_info);
> +    tpm_register_driver(&tpm_emulator_driver);
> +}
> +
> +type_init(tpm_emulator_register)
> diff --git a/hw/tpm/tpm_ioctl.h b/hw/tpm/tpm_ioctl.h
> new file mode 100644
> index 0000000..33564b1
> --- /dev/null
> +++ b/hw/tpm/tpm_ioctl.h

This file is copied from swtpm project. Could swtpm have it installed
on system instead?

> @@ -0,0 +1,246 @@
> +/*
> + * tpm_ioctl.h
> + *
> + * (c) Copyright IBM Corporation 2014, 2015.
> + *
> + * This file is licensed under the terms of the 3-clause BSD license
> + */
> +#ifndef _TPM_IOCTL_H_
> +#define _TPM_IOCTL_H_
> +
> +#include <stdint.h>
> +#include <sys/uio.h>
> +#include <sys/types.h>
> +#include <sys/ioctl.h>
> +
> +/*
> + * Every response from a command involving a TPM command execution must hold
> + * the ptm_res as the first element.
> + * ptm_res corresponds to the error code of a command executed by the TPM.
> + */
> +
> +typedef uint32_t ptm_res;
> +
> +/* PTM_GET_TPMESTABLISHED: get the establishment bit */
> +struct ptm_est {
> +    union {
> +        struct {
> +            ptm_res tpm_result;
> +            unsigned char bit; /* TPM established bit */
> +        } resp; /* response */
> +    } u;
> +};
> +
> +/* PTM_RESET_TPMESTABLISHED: reset establishment bit */
> +struct ptm_reset_est {
> +    union {
> +        struct {
> +            uint8_t loc; /* locality to use */
> +        } req; /* request */
> +        struct {
> +            ptm_res tpm_result;
> +        } resp; /* response */
> +    } u;
> +};
> +
> +/* PTM_INIT */
> +struct ptm_init {
> +    union {
> +        struct {
> +            uint32_t init_flags; /* see definitions below */
> +        } req; /* request */
> +        struct {
> +            ptm_res tpm_result;
> +        } resp; /* response */
> +    } u;
> +};
> +
> +/* above init_flags */
> +#define PTM_INIT_FLAG_DELETE_VOLATILE (1 << 0)
> +    /* delete volatile state file after reading it */
> +
> +/* PTM_SET_LOCALITY */
> +struct ptm_loc {
> +    union {
> +        struct {
> +            uint8_t loc; /* locality to set */
> +        } req; /* request */
> +        struct {
> +            ptm_res tpm_result;
> +        } resp; /* response */
> +    } u;
> +};
> +
> +/* PTM_HASH_DATA: hash given data */
> +struct ptm_hdata {
> +    union {
> +        struct {
> +            uint32_t length;
> +            uint8_t data[4096];
> +        } req; /* request */
> +        struct {
> +            ptm_res tpm_result;
> +        } resp; /* response */
> +    } u;
> +};
> +
> +/*
> + * size of the TPM state blob to transfer; x86_64 can handle 8k,
> + * ppc64le only ~7k; keep the response below a 4k page size
> + */
> +#define PTM_STATE_BLOB_SIZE (3 * 1024)
> +
> +/*
> + * The following is the data structure to get state blobs from the TPM.
> + * If the size of the state blob exceeds the PTM_STATE_BLOB_SIZE, multiple reads
> + * with this ioctl and with adjusted offset are necessary. All bytes
> + * must be transferred and the transfer is done once the last byte has been
> + * returned.
> + * It is possible to use the read() interface for reading the data; however, the
> + * first bytes of the state blob will be part of the response to the ioctl(); a
> + * subsequent read() is only necessary if the total length (totlength) exceeds
> + * the number of received bytes. seek() is not supported.
> + */
> +struct ptm_getstate {
> +    union {
> +        struct {
> +            uint32_t state_flags; /* may be: PTM_STATE_FLAG_DECRYPTED */
> +            uint32_t type;        /* which blob to pull */
> +            uint32_t offset;      /* offset from where to read */
> +        } req; /* request */
> +        struct {
> +            ptm_res tpm_result;
> +            uint32_t state_flags; /* may be: PTM_STATE_FLAG_ENCRYPTED */
> +            uint32_t totlength;   /* total length that will be transferred */
> +            uint32_t length;      /* number of bytes in following buffer */
> +            uint8_t  data[PTM_STATE_BLOB_SIZE];
> +        } resp; /* response */
> +    } u;
> +};
> +
> +/* TPM state blob types */
> +#define PTM_BLOB_TYPE_PERMANENT  1
> +#define PTM_BLOB_TYPE_VOLATILE   2
> +#define PTM_BLOB_TYPE_SAVESTATE  3
> +
> +/* state_flags above : */
> +#define PTM_STATE_FLAG_DECRYPTED     1 /* on input:  get decrypted state */
> +#define PTM_STATE_FLAG_ENCRYPTED     2 /* on output: state is encrypted */
> +
> +/*
> + * The following is the data structure to set state blobs in the TPM.
> + * If the size of the state blob exceeds the PTM_STATE_BLOB_SIZE, multiple
> + * 'writes' using this ioctl are necessary. The last packet is indicated
> + * by the length being smaller than the PTM_STATE_BLOB_SIZE.
> + * The very first packet may have a length indicator of '0' enabling
> + * a write() with all the bytes from a buffer. If the write() interface
> + * is used, a final ioctl with a non-full buffer must be made to indicate
> + * that all data were transferred (a write with 0 bytes would not work).
> + */
> +struct ptm_setstate {
> +    union {
> +        struct {
> +            uint32_t state_flags; /* may be PTM_STATE_FLAG_ENCRYPTED */
> +            uint32_t type;        /* which blob to set */
> +            uint32_t length;      /* length of the data;
> +                                     use 0 on the first packet to
> +                                     transfer using write() */
> +            uint8_t data[PTM_STATE_BLOB_SIZE];
> +        } req; /* request */
> +        struct {
> +            ptm_res tpm_result;
> +        } resp; /* response */
> +    } u;
> +};
> +
> +/*
> + * PTM_GET_CONFIG: Data structure to get runtime configuration information
> + * such as which keys are applied.
> + */
> +struct ptm_getconfig {
> +    union {
> +        struct {
> +            ptm_res tpm_result;
> +            uint32_t flags;
> +        } resp; /* response */
> +    } u;
> +};
> +
> +#define PTM_CONFIG_FLAG_FILE_KEY        0x1
> +#define PTM_CONFIG_FLAG_MIGRATION_KEY   0x2
> +
> +
> +typedef uint64_t ptm_cap;
> +typedef struct ptm_est ptm_est;
> +typedef struct ptm_reset_est ptm_reset_est;
> +typedef struct ptm_loc ptm_loc;
> +typedef struct ptm_hdata ptm_hdata;
> +typedef struct ptm_init ptm_init;
> +typedef struct ptm_getstate ptm_getstate;
> +typedef struct ptm_setstate ptm_setstate;
> +typedef struct ptm_getconfig ptm_getconfig;
> +
> +/* capability flags returned by PTM_GET_CAPABILITY */
> +#define PTM_CAP_INIT               (1)
> +#define PTM_CAP_SHUTDOWN           (1 << 1)
> +#define PTM_CAP_GET_TPMESTABLISHED (1 << 2)
> +#define PTM_CAP_SET_LOCALITY       (1 << 3)
> +#define PTM_CAP_HASHING            (1 << 4)
> +#define PTM_CAP_CANCEL_TPM_CMD     (1 << 5)
> +#define PTM_CAP_STORE_VOLATILE     (1 << 6)
> +#define PTM_CAP_RESET_TPMESTABLISHED (1 << 7)
> +#define PTM_CAP_GET_STATEBLOB      (1 << 8)
> +#define PTM_CAP_SET_STATEBLOB      (1 << 9)
> +#define PTM_CAP_STOP               (1 << 10)
> +#define PTM_CAP_GET_CONFIG         (1 << 11)
> +#define PTM_CAP_SET_DATAFD         (1 << 12)
> +
> +enum {
> +    PTM_GET_CAPABILITY     = _IOR('P', 0, ptm_cap),
> +    PTM_INIT               = _IOWR('P', 1, ptm_init),
> +    PTM_SHUTDOWN           = _IOR('P', 2, ptm_res),
> +    PTM_GET_TPMESTABLISHED = _IOR('P', 3, ptm_est),
> +    PTM_SET_LOCALITY       = _IOWR('P', 4, ptm_loc),
> +    PTM_HASH_START         = _IOR('P', 5, ptm_res),
> +    PTM_HASH_DATA          = _IOWR('P', 6, ptm_hdata),
> +    PTM_HASH_END           = _IOR('P', 7, ptm_res),
> +    PTM_CANCEL_TPM_CMD     = _IOR('P', 8, ptm_res),
> +    PTM_STORE_VOLATILE     = _IOR('P', 9, ptm_res),
> +    PTM_RESET_TPMESTABLISHED = _IOWR('P', 10, ptm_reset_est),
> +    PTM_GET_STATEBLOB      = _IOWR('P', 11, ptm_getstate),
> +    PTM_SET_STATEBLOB      = _IOWR('P', 12, ptm_setstate),
> +    PTM_STOP               = _IOR('P', 13, ptm_res),
> +    PTM_GET_CONFIG         = _IOR('P', 14, ptm_getconfig),
> +    PTM_SET_DATAFD         = _IOR('P', 15, ptm_res),
> +};
> +
> +/*
> + * Commands used by the non-CUSE TPMs
> + *
> + * All messages container big-endian data.
> + *
> + * The return messages only contain the 'resp' part of the unions
> + * in the data structures above. Besides that the limits in the
> + * buffers above (ptm_hdata:u.req.data and ptm_get_state:u.resp.data
> + * and ptm_set_state:u.req.data) are 0xffffffff.
> + */
> +enum {
> +    CMD_GET_CAPABILITY = 1,
> +    CMD_INIT,
> +    CMD_SHUTDOWN,
> +    CMD_GET_TPMESTABLISHED,
> +    CMD_SET_LOCALITY,
> +    CMD_HASH_START,
> +    CMD_HASH_DATA,
> +    CMD_HASH_END,
> +    CMD_CANCEL_TPM_CMD,
> +    CMD_STORE_VOLATILE,
> +    CMD_RESET_TPMESTABLISHED,
> +    CMD_GET_STATEBLOB,
> +    CMD_SET_STATEBLOB,
> +    CMD_STOP,
> +    CMD_GET_CONFIG,
> +    CMD_SET_DATAFD
> +};
> +
> +#endif /* _TPM_IOCTL_H */
> diff --git a/qapi/tpm.json b/qapi/tpm.json
> index e8b2d8d..7093f26 100644
> --- a/qapi/tpm.json
> +++ b/qapi/tpm.json
> @@ -39,10 +39,12 @@
>  # An enumeration of TPM types
>  #
>  # @passthrough: TPM passthrough type
> +# @emulator: Software Emulator TPM type
> +#            Since: 2.11
>  #
>  # Since: 1.5
>  ##
> -{ 'enum': 'TpmType', 'data': [ 'passthrough' ] }
> +{ 'enum': 'TpmType', 'data': [ 'passthrough', 'emulator' ] }
>
>  ##
>  # @query-tpm-types:
> @@ -56,7 +58,7 @@
>  # Example:
>  #
>  # -> { "execute": "query-tpm-types" }
> -# <- { "return": [ "passthrough" ] }
> +# <- { "return": [ "passthrough", "emulator" ] }
>  #
>  ##
>  { 'command': 'query-tpm-types', 'returns': ['TpmType'] }
> @@ -77,16 +79,29 @@
>                                               '*cancel-path' : 'str'} }
>
>  ##
> +# @TPMEmulatorOptions:
> +#
> +# Information about the TPM emulator type
> +#
> +# @chardev: Name of a unix socket chardev
> +#
> +# Since: 2.11
> +##
> +{ 'struct': 'TPMEmulatorOptions', 'data': { 'chardev' : 'str' } }
> +
> +##
>  # @TpmTypeOptions:
>  #
>  # A union referencing different TPM backend types' configuration options
>  #
>  # @type: 'passthrough' The configuration options for the TPM passthrough type
> +#        'emulator' The configuration options for TPM emulator backend type
>  #
>  # Since: 1.5
>  ##
>  { 'union': 'TpmTypeOptions',
> -   'data': { 'passthrough' : 'TPMPassthroughOptions' } }
> +   'data': { 'passthrough' : 'TPMPassthroughOptions',
> +             'emulator': 'TPMEmulatorOptions' } }
>
>  ##
>  # @TPMInfo:
> diff --git a/qemu-options.hx b/qemu-options.hx
> index 77859a2..1e93e53 100644
> --- a/qemu-options.hx
> +++ b/qemu-options.hx
> @@ -3121,7 +3121,9 @@ DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \
>      "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n"
>      "                use path to provide path to a character device; default is /dev/tpm0\n"
>      "                use cancel-path to provide path to TPM's cancel sysfs entry; if\n"
> -    "                not provided it will be searched for in /sys/class/misc/tpm?/device\n",
> +    "                not provided it will be searched for in /sys/class/misc/tpm?/device\n"
> +    "-tpmdev emulator,id=id,chardev=dev\n"
> +    "                configure the TPM device using chardev backend\n",
>      QEMU_ARCH_ALL)
>  STEXI
>
> @@ -3130,8 +3132,8 @@ The general form of a TPM device option is:
>
>  @item -tpmdev @var{backend} ,id=@var{id} [,@var{options}]
>  @findex -tpmdev
> -Backend type must be:
> -@option{passthrough}.
> +Backend type must be either one of the following:
> +@option{passthrough}, @option{emulator}.
>
>  The specific backend type will determine the applicable options.
>  The @code{-tpmdev} option creates the TPM backend and requires a
> @@ -3181,6 +3183,20 @@ To create a passthrough TPM use the following two options:
>  Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by
>  @code{tpmdev=tpm0} in the device option.
>
> +@item -tpmdev emulator, id=@var{id}, chardev=@var{dev}
> +
> +(Linux-host only) Enable access to a TPM emulator using Unix domain socket based
> +chardev backend.
> +
> +@option{chardev} specifies the unique ID of a character device backend that provides connection to the software TPM server.
> +
> +To create a TPM emulator backend device with chardev socket backend:
> +@example
> +
> +-chardev socket,id=chrtpm,path=/tmp/swtpm-ctrl -tpmdev emulator,id=tpm0,chardev=chrtpm -device tpm-tis,tpmdev=tpm0
> +
> +@end example
> +
>  @end table
>
>  ETEXI
> --
> 2.7.4
>

Stefan Berger Sept. 25, 2017, 12:35 a.m. UTC | #3

On 09/24/2017 02:52 PM, Marc-André Lureau wrote:
> Hi
>
> Thanks for the nice update, removing the exec() code, using chardev
> and a private socketpair. Some comments below:
>
> On Fri, Sep 22, 2017 at 2:33 PM, Amarnath Valluri
> <[e-mail]> wrote:
>> This change introduces a new TPM backend driver that can communicate with
>> swtpm(software TPM emulator) using unix domain socket interface. QEMU talks to
>> TPM emulator using socket based chardev backend device.
>>
>> Swtpm uses two Unix sockets for communications, one for plain TPM commands and
>> responses, and one for out-of-band control messages. QEMU passes data socket
>> been used over the control channel.
>>
>> The swtpm and associated tools can be found here:
>>      https://github.com/stefanberger/swtpm
>>
>> The swtpm's control channel protocol specification can be found here:
>>      https://github.com/stefanberger/swtpm/wiki/Control-Channel-Specification
>>
>> Usage:
>>      # setup TPM state directory
>>      mkdir /tmp/mytpm
>>      chown -R tss:root /tmp/mytpm
>>      /usr/bin/swtpm_setup --tpm-state /tmp/mytpm --createek
>>
>>      # Ask qemu to use TPM emulator with given tpm state directory
>>      qemu-system-x86_64 \
>>          [...] \
>>          -chardev socket,id=chrtpm,path=/tmp/swtpm-sock \
>>          -tpmdev emulator,id=tpm0,chardev=chrtpm \
>>          -device tpm-tis,tpmdev=tpm0 \
>>          [...]
>>
>> Signed-off-by: Amarnath Valluri <[e-mail]>
>> ---
>>   configure             |  15 +-
>>   hmp.c                 |   5 +
>>   hw/tpm/Makefile.objs  |   1 +
>>   hw/tpm/tpm_emulator.c | 649 ++++++++++++++++++++++++++++++++++++++++++++++++++
>>   hw/tpm/tpm_ioctl.h    | 246 +++++++++++++++++++
>>   qapi/tpm.json         |  21 +-
>>   qemu-options.hx       |  22 +-
>>   7 files changed, 950 insertions(+), 9 deletions(-)
>>   create mode 100644 hw/tpm/tpm_emulator.c
>>   create mode 100644 hw/tpm/tpm_ioctl.h
>>
>> diff --git a/configure b/configure
>> index cb0f7ed..ce2df2d 100755
>> --- a/configure
>> +++ b/configure
>> @@ -3461,10 +3461,15 @@ fi
>>   ##########################################
>>   # TPM passthrough is only on x86 Linux
>>
>> -if test "$targetos" = Linux && test "$cpu" = i386 -o "$cpu" = x86_64; then
>> -  tpm_passthrough=$tpm
>> +if test "$targetos" = Linux; then
>> +  tpm_emulator=$tpm
>> +  if test "$cpu" = i386 -o "$cpu" = x86_64; then
>> +    tpm_passthrough=$tpm
>> +  else
>> +    tpm_passthrough=no
>> +  fi
>>   else
>> -  tpm_passthrough=no
>> +  tpm_emulator=no
>>   fi
>>
>>   ##########################################
>> @@ -5359,6 +5364,7 @@ echo "gcov enabled      $gcov"
>>   echo "TPM support       $tpm"
>>   echo "libssh2 support   $libssh2"
>>   echo "TPM passthrough   $tpm_passthrough"
>> +echo "TPM emulator      $tpm_emulator"
>>   echo "QOM debugging     $qom_cast_debug"
>>   echo "Live block migration $live_block_migration"
>>   echo "lzo support       $lzo"
>> @@ -5943,6 +5949,9 @@ if test "$tpm" = "yes"; then
>>     if test "$tpm_passthrough" = "yes"; then
>>       echo "CONFIG_TPM_PASSTHROUGH=y" >> $config_host_mak
>>     fi
>> +  if test "$tpm_emulator" = "yes"; then
>> +    echo "CONFIG_TPM_EMULATOR=y" >> $config_host_mak
> It shouldn't require Linux, but posix (and I assume a port to other
> systems isn't impossible). same for build-sys / help / comments.
>
>> +  fi
>>   fi
>>
>>   echo "TRACE_BACKENDS=$trace_backends" >> $config_host_mak
>> diff --git a/hmp.c b/hmp.c
>> index cf62b2e..7e69eca 100644
>> --- a/hmp.c
>> +++ b/hmp.c
>> @@ -995,6 +995,7 @@ void hmp_info_tpm(Monitor *mon, const QDict *qdict)
>>       Error *err = NULL;
>>       unsigned int c = 0;
>>       TPMPassthroughOptions *tpo;
>> +    TPMEmulatorOptions *teo;
>>
>>       info_list = qmp_query_tpm(&err);
>>       if (err) {
>> @@ -1024,6 +1025,10 @@ void hmp_info_tpm(Monitor *mon, const QDict *qdict)
>>                              tpo->has_cancel_path ? ",cancel-path=" : "",
>>                              tpo->has_cancel_path ? tpo->cancel_path : "");
>>               break;
>> +        case TPM_TYPE_EMULATOR:
>> +            teo = ti->options->u.emulator.data;
>> +            monitor_printf(mon, ",chardev=%s", teo->chardev);
>> +            break;
>>           case TPM_TYPE__MAX:
>>               break;
>>           }
>> diff --git a/hw/tpm/Makefile.objs b/hw/tpm/Makefile.objs
>> index 64cecc3..41f0b7a 100644
>> --- a/hw/tpm/Makefile.objs
>> +++ b/hw/tpm/Makefile.objs
>> @@ -1,2 +1,3 @@
>>   common-obj-$(CONFIG_TPM_TIS) += tpm_tis.o
>>   common-obj-$(CONFIG_TPM_PASSTHROUGH) += tpm_passthrough.o tpm_util.o
>> +common-obj-$(CONFIG_TPM_EMULATOR) += tpm_emulator.o tpm_util.o
>> diff --git a/hw/tpm/tpm_emulator.c b/hw/tpm/tpm_emulator.c
>> new file mode 100644
>> index 0000000..c02bbe2
>> --- /dev/null
>> +++ b/hw/tpm/tpm_emulator.c
>> @@ -0,0 +1,649 @@
>> +/*
>> + *  emulator TPM driver
>> + *
>> + *  Copyright (c) 2017 Intel Corporation
>> + *  Author: Amarnath Valluri <[e-mail]>
>> + *
>> + *  Copyright (c) 2010 - 2013 IBM Corporation
>> + *  Authors:
>> + *    Stefan Berger <[e-mail]>
>> + *
>> + *  Copyright (C) 2011 IAIK, Graz University of Technology
>> + *    Author: Andreas Niederl
>> + *
>> + * This library is free software; you can redistribute it and/or
>> + * modify it under the terms of the GNU Lesser General Public
>> + * License as published by the Free Software Foundation; either
>> + * version 2 of the License, or (at your option) any later version.
>> + *
>> + * This library is distributed in the hope that it will be useful,
>> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
>> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
>> + * Lesser General Public License for more details.
>> + *
>> + * You should have received a copy of the GNU Lesser General Public
>> + * License along with this library; if not, see <http://www.gnu.org/licenses/>
>> + *
>> + */
>> +
>> +#include "qemu/osdep.h"
>> +#include "qemu/error-report.h"
>> +#include "qemu/sockets.h"
>> +#include "io/channel-socket.h"
>> +#include "sysemu/tpm_backend.h"
>> +#include "tpm_int.h"
>> +#include "hw/hw.h"
>> +#include "hw/i386/pc.h"
>> +#include "tpm_util.h"
>> +#include "tpm_ioctl.h"
>> +#include "migration/blocker.h"
>> +#include "qapi/error.h"
>> +#include "chardev/char-fe.h"
>> +
>> +#include <fcntl.h>
>> +#include <sys/types.h>
>> +#include <sys/stat.h>
>> +#include <stdio.h>
>> +
>> +#define DEBUG_TPM 0
>> +
>> +#define DPRINT(fmt, ...) do { \
>> +    if (DEBUG_TPM) { \
>> +        fprintf(stderr, fmt, ## __VA_ARGS__); \
>> +    } \
>> +} while (0);
>> +
>> +#define DPRINTF(fmt, ...) DPRINT("tpm-emulator: "fmt"\n", __VA_ARGS__)
> I would define a single DPRINTF() (& drop DPRINT usage below)
>
>
>> +
>> +#define TYPE_TPM_EMULATOR "tpm-emulator"
>> +#define TPM_EMULATOR(obj) \
>> +    OBJECT_CHECK(TPMEmulator, (obj), TYPE_TPM_EMULATOR)
>> +
>> +#define TPM_EMULATOR_IMPLEMENTS_ALL_CAPS(S, cap) (((S)->caps & (cap)) == (cap))
>> +
>> +static const TPMDriverOps tpm_emulator_driver;
>> +
>> +/* data structures */
>> +typedef struct TPMEmulator {
>> +    TPMBackend parent;
>> +
>> +    TPMEmulatorOptions *options;
> Contrary to my comment on previous patch, I realize it is convenient
> to have a qapi pointer here, so you can use the free visitor later.
>
>> +    CharBackend ctrl_dev;
> ctrl_chr perhaps? or just chr or be (the most common name in other devices).
>
>> +    QIOChannel *data_ioc;
>> +    bool op_executing;
>> +    bool op_canceled;
> I think those 2 fields can be dropped, see below.

I agree. It's not necessary for the emulator driver to keep track of 
these states.


>
>> +    bool had_startup_error;
> I think some little refactoring could remove the whole
> had_startup_error() backend & callback before or after the series.
> tpm_backend_startup_tpm() already returns an error code.  device or
> common backend code could handle & remember that.
>
>> +    TPMVersion tpm_version;
> This is probably worth to consider in common code instead, but let's
> not worry about it.
>
>> +    ptm_cap caps; /* capabilities of the TPM */
>> +    uint8_t cur_locty_number; /* last set locality */
>> +    QemuMutex state_lock;
>> +    Error *migration_blocker;
>> +} TPMEmulator;
>> +
>> +
>> +static int tpm_emulator_ctrlcmd(CharBackend *dev, unsigned long cmd, void *msg,
>> +                                size_t msg_len_in, size_t msg_len_out)
>> +{
>> +    uint32_t cmd_no = cpu_to_be32(cmd);
>> +    ssize_t n = sizeof(uint32_t) + msg_len_in;
>> +    uint8_t *buf = NULL;
>> +
>> +    buf = (uint8_t *)malloc(n);
> could be g_alloca() instead. Alternatively, why not call 2 write() instead?

I think for swtpm the commands should arrive in one chunk.


>
> none of the casts in this function are necessary, please remove them.
>
>> +    memcpy(buf, &cmd_no, sizeof(cmd_no));
>> +    memcpy(buf + sizeof(cmd_no), msg, msg_len_in);
>> +
>> +    n += qemu_chr_fe_write_all(dev, (const uint8_t *)buf, n);
> weird
>
>> +    free(buf);
>> +
>> +    if (n > 0) {
> with the n += above, you'll get interesting behaviour :)
>
> You probably want to check if any write above failed, and return early
> for the error case.
>
> Please improve the error handling in this function
>
>> +        if (msg_len_out > 0) {
>> +            n = qemu_chr_fe_read_all(dev, (uint8_t *)msg, msg_len_out);
>> +            /* simulate ioctl return value */
>> +            if (n > 0) {
>> +                n = 0;
>> +            }
>> +        } else {
>> +            n = 0;
>> +        }
>> +    }
>> +    return n;
>> +}
>> +
>> +static int tpm_emulator_unix_tx_bufs(TPMEmulator *tpm_pt,
> tpm_pt was tpm_passthrough I suppose.
>
> Please rename tpm_pt tpm_emu (or I would suggest "self", but this
> isn't common name in qemu code - it's actually common in a close
> c-object world., and it is quite convenient...)
>
>> +                                     const uint8_t *in, uint32_t in_len,
>> +                                     uint8_t *out, uint32_t out_len,
>> +                                     bool *selftest_done)
>> +{
>> +    ssize_t ret;
>> +    bool is_selftest = false;
>> +    const struct tpm_resp_hdr *hdr = NULL;
>> +    Error *err = NULL;
>> +
>> +    tpm_pt->op_canceled = false;
>> +    tpm_pt->op_executing = true;
>> +    if (selftest_done) {
>> +        *selftest_done = false;
>> +        is_selftest = tpm_util_is_selftest(in, in_len);
>> +    }
>> +
>> +    ret = qio_channel_write(tpm_pt->data_ioc, (char *)in, in_len, &err);
> hmm, too bad qio_channel_write() doesn't take a void *
>
> why not write_all()?
>
>> +    if (ret != in_len || err) {
>> +        if (!tpm_pt->op_canceled || errno != ECANCELED) {
> I don't think ECANCELED make sense for emulator code.
>
>> +            error_report("tpm-emulator: error while transmitting data "
>> +                         "to TPM: %s", err ? error_get_pretty(err) : "");
>> +            error_free(err);
>> +        }
>> +        goto err_exit;
>> +    }
>> +
>> +    tpm_pt->op_executing = false;
>> +
>> +    ret = qio_channel_read(tpm_pt->data_ioc, (char *)out, out_len, &err);
>> +    if (ret < 0 || err) {
> read_all() ?
>
>> +        if (!tpm_pt->op_canceled || errno != ECANCELED) {
>> +            error_report("tpm-emulator: error while reading data from "
>> +                         "TPM: %s", err ? error_get_pretty(err) : "");
>> +            error_free(err);
>> +        }
>> +    } else if (ret >= sizeof(*hdr)) {
>> +        hdr = (struct tpm_resp_hdr *)out;
>> +    }
>> +
>> +    if (!hdr || be32_to_cpu(hdr->len) != ret) {
>> +        error_report("tpm-emulator: received invalid response "
>> +                     "packet from TPM with length :%ld", ret);
>> +        ret = -1;
>> +        goto err_exit;
>> +    }
>> +
>> +    if (is_selftest) {
>> +        *selftest_done = (be32_to_cpu(hdr->errcode) == 0);
>> +    }
>> +
>> +    return 0;
>> +
>> +err_exit:
>> +    if (ret < 0) {
>> +        tpm_util_write_fatal_error_response(out, out_len);
>> +    }
>> +
>> +    tpm_pt->op_executing = false;
>> +
>> +    return ret;
>> +}
>> +
>> +static int tpm_emulator_set_locality(TPMEmulator *tpm_pt, uint8_t locty_number)
>> +{
>> +    ptm_loc loc;
>> +
>> +    DPRINTF("%s : locality: 0x%x", __func__, locty_number);
>> +
>> +    if (tpm_pt->cur_locty_number != locty_number) {
> return early instead if ==, to avoid code indent etc
>
>> +        DPRINTF("setting locality : 0x%x", locty_number);
>> +        loc.u.req.loc = locty_number;
> This number isn't set in be like the rest of the protocol?
>
>> +        if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_SET_LOCALITY, &loc,
>> +                             sizeof(loc), sizeof(loc)) < 0) {
>> +            error_report("tpm-emulator: could not set locality : %s",
>> +                         strerror(errno));
>> +            return -1;
>> +        }
>> +        loc.u.resp.tpm_result = be32_to_cpu(loc.u.resp.tpm_result);
>> +        if (loc.u.resp.tpm_result != 0) {
>> +            error_report("tpm-emulator: TPM result for set locality : 0x%x",
>> +                         loc.u.resp.tpm_result);
>> +            return -1;
>> +        }
>> +        tpm_pt->cur_locty_number = locty_number;
>> +    }
>> +    return 0;
>> +}
>> +
>> +static void tpm_emulator_handle_request(TPMBackend *tb, TPMBackendCmd cmd)
>> +{
>> +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
>> +    TPMLocality *locty = NULL;
>> +    bool selftest_done = false;
>> +
>> +    DPRINTF("processing command type %d", cmd);
>> +
>> +    switch (cmd) {
>> +    case TPM_BACKEND_CMD_PROCESS_CMD:
>> +        qemu_mutex_lock(&tpm_pt->state_lock);
>> +        locty = tb->tpm_state->locty_data;
>> +        if (tpm_emulator_set_locality(tpm_pt,
>> +                                      tb->tpm_state->locty_number) < 0) {
>> +            tpm_util_write_fatal_error_response(locty->r_buffer.buffer,
>> +                                           locty->r_buffer.size);
> return / goto here instead of else.
>
>> +        } else {
>> +            tpm_emulator_unix_tx_bufs(tpm_pt, locty->w_buffer.buffer,
>> +                                              locty->w_offset,
>> +                                              locty->r_buffer.buffer,
>> +                                              locty->r_buffer.size,
>> +                                              &selftest_done);
> no error handling?
>
>> +        }
>> +
>> +        tb->recv_data_callback(tb->tpm_state, tb->tpm_state->locty_number,
>> +                               selftest_done);
>> +        qemu_mutex_unlock(&tpm_pt->state_lock);
>> +
>> +        break;
>> +    case TPM_BACKEND_CMD_INIT:
>> +    case TPM_BACKEND_CMD_END:
>> +    case TPM_BACKEND_CMD_TPM_RESET:
>> +        /* nothing to do */
>> +        break;
>> +    }
>> +}
>> +
>> +/*
>> + * Gracefully shut down the external unixio TPM
>> + */
>> +static void tpm_emulator_shutdown(TPMEmulator *tpm_pt)
>> +{
>> +    ptm_res res;
>> +
>> +    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_SHUTDOWN, &res, 0,
>> +                         sizeof(res)) < 0) {
>> +        error_report("tpm-emulator: Could not cleanly shutdown the TPM: %s",
>> +                     strerror(errno));
>> +    } else if (res != 0) {
>> +        error_report("tpm-emulator: TPM result for sutdown: 0x%x",
>> +                     be32_to_cpu(res));
>> +    }
>> +}
>> +
>> +static int tpm_emulator_probe_caps(TPMEmulator *tpm_pt)
>> +{
>> +    DPRINTF("%s", __func__);
>> +    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_GET_CAPABILITY,
>> +                         &tpm_pt->caps, 0, sizeof(tpm_pt->caps)) < 0) {
>> +        error_report("tpm-emulator: probing failed : %s", strerror(errno));
>> +        return -1;
>> +    }
>> +
>> +    tpm_pt->caps = be64_to_cpu(tpm_pt->caps);
>> +
>> +    DPRINTF("capbilities : 0x%lx", tpm_pt->caps);
>> +
>> +    return 0;
>> +}
>> +
>> +static int tpm_emulator_check_caps(TPMEmulator *tpm_pt)
>> +{
>> +    ptm_cap caps = 0;
>> +    const char *tpm = NULL;
>> +
>> +    /* check for min. required capabilities */
>> +    switch (tpm_pt->tpm_version) {
>> +    case TPM_VERSION_1_2:
>> +        caps = PTM_CAP_INIT | PTM_CAP_SHUTDOWN | PTM_CAP_GET_TPMESTABLISHED |
>> +               PTM_CAP_SET_LOCALITY;
>> +        tpm = "1.2";
>> +        break;
>> +    case TPM_VERSION_2_0:
>> +        caps = PTM_CAP_INIT | PTM_CAP_SHUTDOWN | PTM_CAP_GET_TPMESTABLISHED |
>> +               PTM_CAP_SET_LOCALITY | PTM_CAP_RESET_TPMESTABLISHED;
>> +        tpm = "2";
>> +        break;
>> +    case TPM_VERSION_UNSPEC:
>> +        error_report("tpm-emulator: TPM version has not been set");
>> +        return -1;
>> +    }
>> +
>> +    if (!TPM_EMULATOR_IMPLEMENTS_ALL_CAPS(tpm_pt, caps)) {
>> +        error_report("tpm-emulator: TPM does not implement minimum set of "
>> +                     "required capabilities for TPM %s (0x%x)", tpm, (int)caps);
>> +        return -1;
>> +    }
>> +
>> +    return 0;
>> +}
>> +
>> +static int tpm_emulator_startup_tpm(TPMBackend *tb)
>> +{
>> +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
>> +    ptm_init init;
>> +    ptm_res res;
>> +
>> +    DPRINTF("%s", __func__);
>> +    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_INIT, &init, sizeof(init),
>> +                         sizeof(init)) < 0) {
>> +        error_report("tpm-emulator: could not send INIT: %s",
>> +                     strerror(errno));
>> +        goto err_exit;
>> +    }
>> +
>> +    res = be32_to_cpu(init.u.resp.tpm_result);
>> +    if (res) {
>> +        error_report("tpm-emulator: TPM result for CMD_INIT: 0x%x", res);
>> +        goto err_exit;
>> +    }
>> +    return 0;
>> +
>> +err_exit:
>> +    tpm_pt->had_startup_error = true;
>> +    return -1;
>> +}
>> +
>> +static bool tpm_emulator_get_tpm_established_flag(TPMBackend *tb)
>> +{
>> +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
>> +    ptm_est est;
>> +
>> +    DPRINTF("%s", __func__);
>> +    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_GET_TPMESTABLISHED, &est, 0,
>> +                         sizeof(est)) < 0) {
>> +        error_report("tpm-emulator: Could not get the TPM established flag: %s",
>> +                     strerror(errno));
>> +        return false;
>> +    }
>> +    DPRINTF("established flag: %0x", est.u.resp.bit);
>> +
>> +    return (est.u.resp.bit != 0);
>> +}
>> +
>> +static int tpm_emulator_reset_tpm_established_flag(TPMBackend *tb,
>> +                                                   uint8_t locty)
>> +{
>> +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
>> +    ptm_reset_est reset_est;
>> +    ptm_res res;
>> +
>> +    /* only a TPM 2.0 will support this */
>> +    if (tpm_pt->tpm_version == TPM_VERSION_2_0) {
>> +        reset_est.u.req.loc = tpm_pt->cur_locty_number;
>> +
>> +        if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_RESET_TPMESTABLISHED,
>> +                                 &reset_est, sizeof(reset_est),
>> +                                 sizeof(reset_est)) < 0) {
>> +            error_report("tpm-emulator: Could not reset the establishment bit: "
>> +                          "%s", strerror(errno));
>> +            return -1;
>> +        }
>> +
>> +        res = be32_to_cpu(reset_est.u.resp.tpm_result);
>> +        if (res) {
>> +            error_report("tpm-emulator: TPM result for rest establixhed flag: "
>> +                         "0x%x", res);
>> +            return -1;
>> +        }
>> +    }
>> +
>> +    return 0;
>> +}
>> +
>> +static bool tpm_emulator_had_startup_error(TPMBackend *tb)
>> +{
>> +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
>> +
>> +    return tpm_pt->had_startup_error;
>> +}
>> +
>> +static void tpm_emulator_cancel_cmd(TPMBackend *tb)
>> +{
>> +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
>> +    ptm_res res;
>> +
>> +    /*
>> +     * As of Linux 3.7 the tpm_tis driver does not properly cancel
>> +     * commands on all TPM manufacturers' TPMs.
>> +     * Only cancel if we're busy so we don't cancel someone else's
>> +     * command, e.g., a command executed on the host.
>> +     */
>> +    if (tpm_pt->op_executing) {
> The field is set in the worker thread. This is racy. Fortunately this
> is not relevant for emulator, I think you can simply drop that check
> and the variable. Stefan should confirm though.
>
>> +        if (TPM_EMULATOR_IMPLEMENTS_ALL_CAPS(tpm_pt, PTM_CAP_CANCEL_TPM_CMD)) {
>> +            if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_CANCEL_TPM_CMD,
>> +                                     &res, 0, sizeof(res)) < 0) {
>> +                error_report("tpm-emulator: Could not cancel command: %s",
>> +                             strerror(errno));
>> +            } else if (res != 0) {
>> +                error_report("tpm-emulator: Failed to cancel TPM: 0x%x",
>> +                             be32_to_cpu(res));
>> +            } else {
>> +                tpm_pt->op_canceled = true;
>> +            }
>> +        }
>> +    }
>> +}
>> +
>> +static void tpm_emulator_reset(TPMBackend *tb)
>> +{
>> +    DPRINTF("%s", __func__);
>> +
>> +    tpm_emulator_cancel_cmd(tb);
>> +}
>> +
>> +static TPMVersion tpm_emulator_get_tpm_version(TPMBackend *tb)
>> +{
>> +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
>> +
>> +    return tpm_pt->tpm_version;
>> +}
>> +
>> +static void tpm_emulator_block_migration(TPMEmulator *tpm_pt)
>> +{
>> +    Error *err = NULL;
>> +
>> +    error_setg(&tpm_pt->migration_blocker,
>> +               "Migration disabled: TPM emulator not yet migratable");
>> +    migrate_add_blocker(tpm_pt->migration_blocker, &err);
>> +    if (err) {
>> +        error_free(err);
> probably better to report_err it instead
>
>> +        error_free(tpm_pt->migration_blocker);
>> +        tpm_pt->migration_blocker = NULL;
> and return an error code.
>
>> +    }
>> +}
>> +
>> +static int tpm_emulator_prepare_data_fd(TPMEmulator *tpm_pt)
>> +{
>> +    ptm_res res;
>> +    Error *err = NULL;
>> +    int fds[2] = { -1, -1 };
>> +
>> +    if (socketpair(AF_UNIX, SOCK_SEQPACKET, 0, fds) < 0) {
>> +        error_report("tpm-emulator: Failed to create socketpair");
>> +        return -1;
>> +    }
>> +
>> +    qemu_chr_fe_set_msgfds(&tpm_pt->ctrl_dev, fds + 1, 1);
>> +
>> +    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_SET_DATAFD, &res, 0,
>> +                    sizeof(res)) || res != 0) {
> Yay! for making life easier and hiding a protocol detail.
>
>> +        error_report("tpm-emulator: Failed to send CMD_SET_DATAFD: %s",
>> +                     strerror(errno));
>> +        goto err_exit;
>> +    }
>> +
>> +    tpm_pt->data_ioc = QIO_CHANNEL(qio_channel_socket_new_fd(fds[0], &err));
>> +    if (err) {
>> +        error_report("tpm-emulator: Failed to create io channel : %s",
>> +                       error_get_pretty(err));
> error_prepend()?
>
>> +        error_free(err);
>> +        goto err_exit;
>> +    }
> close fds[1] ?
>
>> +
>> +    return 0;
>> +
>> +err_exit:
>> +    closesocket(fds[0]);
>> +    closesocket(fds[1]);
>> +    return -1;
>> +}
>> +
>> +static int tpm_emulator_handle_device_opts(TPMEmulator *tpm_pt, QemuOpts *opts)
>> +{
>> +    const char *value;
>> +
>> +    value = qemu_opt_get(opts, "chardev");
>> +    if (value) {
>> +        Error *err = NULL;
>> +        Chardev *dev = qemu_chr_find(value);
>> +
>> +        tpm_pt->options->chardev = g_strdup(value);
>> +
>> +        if (!dev || !qemu_chr_fe_init(&tpm_pt->ctrl_dev, dev, &err)) {
>> +            error_report("tpm-emulator: No valid chardev found at '%s': %s",
>> +                         value, err ? error_get_pretty(err) : "");
>> +            error_free(err);
> error_prepend
>
>> +            goto err;
>> +        }
>> +    }
>> +
>> +    if (tpm_emulator_prepare_data_fd(tpm_pt) < 0) {
>> +        goto err;
>> +    }
>> +
>> +    /* FIXME: tpm_util_test_tpmdev() accepts only on socket fd, as it also used
>> +     * by passthrough driver, which not yet using GIOChannel.
>> +     */
>> +    if (tpm_util_test_tpmdev(QIO_CHANNEL_SOCKET(tpm_pt->data_ioc)->fd,
>> +                             &tpm_pt->tpm_version)) {
>> +        error_report("'%s' is not emulating TPM device. Error: %s",
>> +                      tpm_pt->options->chardev, strerror(errno));
>> +        goto err;
>> +    }
>> +
>> +    DPRINTF("TPM Version %s", tpm_pt->tpm_version == TPM_VERSION_1_2 ? "1.2" :
>> +             (tpm_pt->tpm_version == TPM_VERSION_2_0 ?  "2.0" : "Unspecified"));
>> +
>> +    if (tpm_emulator_probe_caps(tpm_pt) ||
>> +        tpm_emulator_check_caps(tpm_pt)) {
>> +        goto err;
>> +    }
>> +
>> +    tpm_emulator_block_migration(tpm_pt);
>> +
>> +    return 0;
>> +
>> +err:
>> +    DPRINT("Startup error\n");
>> +    return -1;
>> +}
>> +
>> +static TPMBackend *tpm_emulator_create(QemuOpts *opts, const char *id)
>> +{
>> +    TPMBackend *tb = TPM_BACKEND(object_new(TYPE_TPM_EMULATOR));
>> +
>> +    tb->id = g_strdup(id);
>> +
>> +    if (tpm_emulator_handle_device_opts(TPM_EMULATOR(tb), opts)) {
>> +        goto err_exit;
>> +    }
>> +
>> +    return tb;
>> +
>> +err_exit:
>> +    object_unref(OBJECT(tb));
>> +
>> +    return NULL;
>> +}
>> +
>> +static TpmTypeOptions *tpm_emulator_get_tpm_options(TPMBackend *tb)
>> +{
>> +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
>> +    TpmTypeOptions *options = NULL;
>> +    TPMEmulatorOptions *eoptions = NULL;
>> +
>> +    eoptions = g_new0(TPMEmulatorOptions, 1);
>> +    if (!eoptions) {
>> +        return NULL;
>> +    }
>> +    DPRINTF("%s", __func__);
>> +
>> +    eoptions->chardev = g_strdup(tpm_pt->options->chardev);
>> +    options = g_new0(TpmTypeOptions, 1);
>> +    if (!options) {
>> +        qapi_free_TPMEmulatorOptions(eoptions);
>> +        return NULL;
>> +    }
>> +
>> +    options->type = TPM_TYPE_EMULATOR;
>> +    options->u.emulator.data = eoptions;
> I think this is a job for QAPI_CLONE.
>
>> +
>> +    return options;
>> +}
>> +
>> +static const QemuOptDesc tpm_emulator_cmdline_opts[] = {
>> +    TPM_STANDARD_CMDLINE_OPTS,
>> +    {
>> +        .name = "chardev",
>> +        .type = QEMU_OPT_STRING,
>> +        .help = "Character device to use for out-of-band control messages",
>> +    },
>> +    { /* end of list */ },
>> +};
>> +
>> +static const TPMDriverOps tpm_emulator_driver = {
>> +    .type                     = TPM_TYPE_EMULATOR,
>> +    .opts                     = tpm_emulator_cmdline_opts,
>> +    .desc                     = "TPM emulator backend driver",
>> +
>> +    .create                   = tpm_emulator_create,
>> +    .startup_tpm              = tpm_emulator_startup_tpm,
>> +    .reset                    = tpm_emulator_reset,
>> +    .had_startup_error        = tpm_emulator_had_startup_error,
>> +    .cancel_cmd               = tpm_emulator_cancel_cmd,
>> +    .get_tpm_established_flag = tpm_emulator_get_tpm_established_flag,
>> +    .reset_tpm_established_flag = tpm_emulator_reset_tpm_established_flag,
>> +    .get_tpm_version          = tpm_emulator_get_tpm_version,
>> +    .get_tpm_options          = tpm_emulator_get_tpm_options,
>> +};
>> +
>> +static void tpm_emulator_inst_init(Object *obj)
>> +{
>> +    TPMEmulator *tpm_pt = TPM_EMULATOR(obj);
>> +
>> +    DPRINTF("%s", __func__);
>> +    tpm_pt->options = g_new0(TPMEmulatorOptions, 1);
>> +    tpm_pt->op_executing = tpm_pt->op_canceled = false;
>> +    tpm_pt->had_startup_error = false;
>> +    tpm_pt->cur_locty_number = ~0;
>> +    qemu_mutex_init(&tpm_pt->state_lock);
>> +}
>> +
>> +static void tpm_emulator_inst_finalize(Object *obj)
>> +{
>> +    TPMEmulator *tpm_pt = TPM_EMULATOR(obj);
>> +
>> +    tpm_emulator_cancel_cmd(TPM_BACKEND(obj));
>> +    tpm_emulator_shutdown(tpm_pt);
>> +
>> +    if (tpm_pt->data_ioc) {
>> +        qio_channel_close(tpm_pt->data_ioc, NULL);
>> +    }
>> +
>> +    qemu_chr_fe_deinit(&tpm_pt->ctrl_dev, false);
>> +
>> +    if (tpm_pt->options) {
>> +        qapi_free_TPMEmulatorOptions(tpm_pt->options);
>> +    }
>> +
>> +    if (tpm_pt->migration_blocker) {
>> +        migrate_del_blocker(tpm_pt->migration_blocker);
>> +        error_free(tpm_pt->migration_blocker);
>> +    }
>> +}
>> +
>> +static void tpm_emulator_class_init(ObjectClass *klass, void *data)
>> +{
>> +    TPMBackendClass *tbc = TPM_BACKEND_CLASS(klass);
>> +    tbc->ops = &tpm_emulator_driver;
>> +    tbc->handle_request = tpm_emulator_handle_request;
>> +}
>> +
>> +static const TypeInfo tpm_emulator_info = {
>> +    .name = TYPE_TPM_EMULATOR,
>> +    .parent = TYPE_TPM_BACKEND,
>> +    .instance_size = sizeof(TPMEmulator),
>> +    .class_init = tpm_emulator_class_init,
>> +    .instance_init = tpm_emulator_inst_init,
>> +    .instance_finalize = tpm_emulator_inst_finalize,
>> +};
>> +
>> +static void tpm_emulator_register(void)
>> +{
>> +    type_register_static(&tpm_emulator_info);
>> +    tpm_register_driver(&tpm_emulator_driver);
>> +}
>> +
>> +type_init(tpm_emulator_register)
>> diff --git a/hw/tpm/tpm_ioctl.h b/hw/tpm/tpm_ioctl.h
>> new file mode 100644
>> index 0000000..33564b1
>> --- /dev/null
>> +++ b/hw/tpm/tpm_ioctl.h
> This file is copied from swtpm project. Could swtpm have it installed
> on system instead?


I think we'll have to carry this file here for a while until swtpm is 
packaged and distros provide it.

    Stefan

Amarnath Valluri Sept. 26, 2017, 12:05 p.m. UTC | #4

Hi Marc,

Thanks for your time reviewing this patchset. Please find my inline
comments.

On Sun, 2017-09-24 at 20:52 +0200, Marc-André Lureau wrote:
> Hi

> 

> Thanks for the nice update, removing the exec() code, using chardev

> and a private socketpair. Some comments below:

> 

> On Fri, Sep 22, 2017 at 2:33 PM, Amarnath Valluri

> <[e-mail]> wrote:

> > 

> > This change introduces a new TPM backend driver that can

> > communicate with

> > swtpm(software TPM emulator) using unix domain socket interface.

> > QEMU talks to

> > TPM emulator using socket based chardev backend device.

> > 

> > Swtpm uses two Unix sockets for communications, one for plain TPM

> > commands and

> > responses, and one for out-of-band control messages. QEMU passes

> > data socket

> > been used over the control channel.

> > 

> > The swtpm and associated tools can be found here:

> >     https://github.com/stefanberger/swtpm

> > 

> > The swtpm's control channel protocol specification can be found

> > here:

> >     https://github.com/stefanberger/swtpm/wiki/Control-Channel-Spec

> > ification

> > 

> > Usage:

> >     # setup TPM state directory

> >     mkdir /tmp/mytpm

> >     chown -R tss:root /tmp/mytpm

> >     /usr/bin/swtpm_setup --tpm-state /tmp/mytpm --createek

> > 

> >     # Ask qemu to use TPM emulator with given tpm state directory

> >     qemu-system-x86_64 \

> >         [...] \

> >         -chardev socket,id=chrtpm,path=/tmp/swtpm-sock \

> >         -tpmdev emulator,id=tpm0,chardev=chrtpm \

> >         -device tpm-tis,tpmdev=tpm0 \

> >         [...]

> > 

> > Signed-off-by: Amarnath Valluri <[e-mail]>

> > ---

> >  configure             |  15 +-

> >  hmp.c                 |   5 +

> >  hw/tpm/Makefile.objs  |   1 +

> >  hw/tpm/tpm_emulator.c | 649

> > ++++++++++++++++++++++++++++++++++++++++++++++++++

> >  hw/tpm/tpm_ioctl.h    | 246 +++++++++++++++++++

> >  qapi/tpm.json         |  21 +-

> >  qemu-options.hx       |  22 +-

> >  7 files changed, 950 insertions(+), 9 deletions(-)

> >  create mode 100644 hw/tpm/tpm_emulator.c

> >  create mode 100644 hw/tpm/tpm_ioctl.h

> > 

> > diff --git a/configure b/configure

> > index cb0f7ed..ce2df2d 100755

> > --- a/configure

> > +++ b/configure

> > @@ -3461,10 +3461,15 @@ fi

> >  ##########################################

> >  # TPM passthrough is only on x86 Linux

> > 

> > -if test "$targetos" = Linux && test "$cpu" = i386 -o "$cpu" =

> > x86_64; then

> > -  tpm_passthrough=$tpm

> > +if test "$targetos" = Linux; then

> > +  tpm_emulator=$tpm

> > +  if test "$cpu" = i386 -o "$cpu" = x86_64; then

> > +    tpm_passthrough=$tpm

> > +  else

> > +    tpm_passthrough=no

> > +  fi

> >  else

> > -  tpm_passthrough=no

> > +  tpm_emulator=no

> >  fi

> > 

> >  ##########################################

> > @@ -5359,6 +5364,7 @@ echo "gcov enabled      $gcov"

> >  echo "TPM support       $tpm"

> >  echo "libssh2 support   $libssh2"

> >  echo "TPM passthrough   $tpm_passthrough"

> > +echo "TPM emulator      $tpm_emulator"

> >  echo "QOM debugging     $qom_cast_debug"

> >  echo "Live block migration $live_block_migration"

> >  echo "lzo support       $lzo"

> > @@ -5943,6 +5949,9 @@ if test "$tpm" = "yes"; then

> >    if test "$tpm_passthrough" = "yes"; then

> >      echo "CONFIG_TPM_PASSTHROUGH=y" >> $config_host_mak

> >    fi

> > +  if test "$tpm_emulator" = "yes"; then

> > +    echo "CONFIG_TPM_EMULATOR=y" >> $config_host_mak

> It shouldn't require Linux, but posix (and I assume a port to other

> systems isn't impossible). same for build-sys / help / comments.

I agree, Can you suggest, what is the Qemu way of limiting this to
'posix'.
> 

> > 

> > +  fi

> >  fi

> > 

> >  echo "TRACE_BACKENDS=$trace_backends" >> $config_host_mak

> > diff --git a/hmp.c b/hmp.c

> > index cf62b2e..7e69eca 100644

> > --- a/hmp.c

> > +++ b/hmp.c

> > @@ -995,6 +995,7 @@ void hmp_info_tpm(Monitor *mon, const QDict

> > *qdict)

> >      Error *err = NULL;

> >      unsigned int c = 0;

> >      TPMPassthroughOptions *tpo;

> > +    TPMEmulatorOptions *teo;

> > 

> >      info_list = qmp_query_tpm(&err);

> >      if (err) {

> > @@ -1024,6 +1025,10 @@ void hmp_info_tpm(Monitor *mon, const QDict

> > *qdict)

> >                             tpo->has_cancel_path ? ",cancel-path="

> > : "",

> >                             tpo->has_cancel_path ? tpo->cancel_path 

> > : "");

> >              break;

> > +        case TPM_TYPE_EMULATOR:

> > +            teo = ti->options->u.emulator.data;

> > +            monitor_printf(mon, ",chardev=%s", teo->chardev);

> > +            break;

> >          case TPM_TYPE__MAX:

> >              break;

> >          }

> > diff --git a/hw/tpm/Makefile.objs b/hw/tpm/Makefile.objs

> > index 64cecc3..41f0b7a 100644

> > --- a/hw/tpm/Makefile.objs

> > +++ b/hw/tpm/Makefile.objs

> > @@ -1,2 +1,3 @@

> >  common-obj-$(CONFIG_TPM_TIS) += tpm_tis.o

> >  common-obj-$(CONFIG_TPM_PASSTHROUGH) += tpm_passthrough.o

> > tpm_util.o

> > +common-obj-$(CONFIG_TPM_EMULATOR) += tpm_emulator.o tpm_util.o

> > diff --git a/hw/tpm/tpm_emulator.c b/hw/tpm/tpm_emulator.c

> > new file mode 100644

> > index 0000000..c02bbe2

> > --- /dev/null

> > +++ b/hw/tpm/tpm_emulator.c

> > @@ -0,0 +1,649 @@

> > +/*

> > + *  emulator TPM driver

> > + *

> > + *  Copyright (c) 2017 Intel Corporation

> > + *  Author: Amarnath Valluri <[e-mail]>

> > + *

> > + *  Copyright (c) 2010 - 2013 IBM Corporation

> > + *  Authors:

> > + *    Stefan Berger <[e-mail]>

> > + *

> > + *  Copyright (C) 2011 IAIK, Graz University of Technology

> > + *    Author: Andreas Niederl

> > + *

> > + * This library is free software; you can redistribute it and/or

> > + * modify it under the terms of the GNU Lesser General Public

> > + * License as published by the Free Software Foundation; either

> > + * version 2 of the License, or (at your option) any later

> > version.

> > + *

> > + * This library is distributed in the hope that it will be useful,

> > + * but WITHOUT ANY WARRANTY; without even the implied warranty of

> > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

> > GNU

> > + * Lesser General Public License for more details.

> > + *

> > + * You should have received a copy of the GNU Lesser General

> > Public

> > + * License along with this library; if not, see <http://www.gnu.or

> > g/licenses/>

> > + *

> > + */

> > +

> > +#include "qemu/osdep.h"

> > +#include "qemu/error-report.h"

> > +#include "qemu/sockets.h"

> > +#include "io/channel-socket.h"

> > +#include "sysemu/tpm_backend.h"

> > +#include "tpm_int.h"

> > +#include "hw/hw.h"

> > +#include "hw/i386/pc.h"

> > +#include "tpm_util.h"

> > +#include "tpm_ioctl.h"

> > +#include "migration/blocker.h"

> > +#include "qapi/error.h"

> > +#include "chardev/char-fe.h"

> > +

> > +#include <fcntl.h>

> > +#include <sys/types.h>

> > +#include <sys/stat.h>

> > +#include <stdio.h>

> > +

> > +#define DEBUG_TPM 0

> > +

> > +#define DPRINT(fmt, ...) do { \

> > +    if (DEBUG_TPM) { \

> > +        fprintf(stderr, fmt, ## __VA_ARGS__); \

> > +    } \

> > +} while (0);

> > +

> > +#define DPRINTF(fmt, ...) DPRINT("tpm-emulator: "fmt"\n",

> > __VA_ARGS__)

> I would define a single DPRINTF() (& drop DPRINT usage below)

Ok, will do
> 

> 

> > 

> > +

> > +#define TYPE_TPM_EMULATOR "tpm-emulator"

> > +#define TPM_EMULATOR(obj) \

> > +    OBJECT_CHECK(TPMEmulator, (obj), TYPE_TPM_EMULATOR)

> > +

> > +#define TPM_EMULATOR_IMPLEMENTS_ALL_CAPS(S, cap) (((S)->caps &

> > (cap)) == (cap))

> > +

> > +static const TPMDriverOps tpm_emulator_driver;

> > +

> > +/* data structures */

> > +typedef struct TPMEmulator {

> > +    TPMBackend parent;

> > +

> > +    TPMEmulatorOptions *options;

> Contrary to my comment on previous patch, I realize it is convenient

> to have a qapi pointer here, so you can use the free visitor later.

> 

> > 

> > +    CharBackend ctrl_dev;

> ctrl_chr perhaps? or just chr or be (the most common name in other

> devices).

> 

> > 

> > +    QIOChannel *data_ioc;

> > +    bool op_executing;

> > +    bool op_canceled;

> I think those 2 fields can be dropped, see below.

> 

> > 

> > +    bool had_startup_error;

> I think some little refactoring could remove the whole

> had_startup_error() backend & callback before or after the series.

> tpm_backend_startup_tpm() already returns an error code.  device or

> common backend code could handle & remember that.

Yes, i agree, we can avoid had_startup_error() from DriverOps, i will
do this.
> 

> > 

> > +    TPMVersion tpm_version;

> This is probably worth to consider in common code instead, but let's

> not worry about it.

> 

> > 

> > +    ptm_cap caps; /* capabilities of the TPM */

> > +    uint8_t cur_locty_number; /* last set locality */

> > +    QemuMutex state_lock;

> > +    Error *migration_blocker;

> > +} TPMEmulator;

> > +

> > +

> > +static int tpm_emulator_ctrlcmd(CharBackend *dev, unsigned long

> > cmd, void *msg,

> > +                                size_t msg_len_in, size_t

> > msg_len_out)

> > +{

> > +    uint32_t cmd_no = cpu_to_be32(cmd);

> > +    ssize_t n = sizeof(uint32_t) + msg_len_in;

> > +    uint8_t *buf = NULL;

> > +

> > +    buf = (uint8_t *)malloc(n);

> could be g_alloca() instead. Alternatively, why not call 2 write()

> instead?

> 

> none of the casts in this function are necessary, please remove them.

Ok, will change to aclloca()
> 

> > 

> > +    memcpy(buf, &cmd_no, sizeof(cmd_no));

> > +    memcpy(buf + sizeof(cmd_no), msg, msg_len_in);

> > +

> > +    n += qemu_chr_fe_write_all(dev, (const uint8_t *)buf, n);

> weird

> 

> > 

> > +    free(buf);

> > +

> > +    if (n > 0) {

> with the n += above, you'll get interesting behaviour :)

Ya, it was typo :)
> 

> You probably want to check if any write above failed, and return

> early

> for the error case.

> 

> Please improve the error handling in this function

> 

> > 

> > +        if (msg_len_out > 0) {

> > +            n = qemu_chr_fe_read_all(dev, (uint8_t *)msg,

> > msg_len_out);

> > +            /* simulate ioctl return value */

> > +            if (n > 0) {

> > +                n = 0;

> > +            }

> > +        } else {

> > +            n = 0;

> > +        }

> > +    }

> > +    return n;

> > +}

> > +

> > +static int tpm_emulator_unix_tx_bufs(TPMEmulator *tpm_pt,

> tpm_pt was tpm_passthrough I suppose.

> 

> Please rename tpm_pt tpm_emu (or I would suggest "self", but this

> isn't common name in qemu code - it's actually common in a close

> c-object world., and it is quite convenient...)

My interpretation about _pt was 'pointer' ;-) i will consider your
suggetion.
> 

> > 

> > +                                     const uint8_t *in, uint32_t

> > in_len,

> > +                                     uint8_t *out, uint32_t

> > out_len,

> > +                                     bool *selftest_done)

> > +{

> > +    ssize_t ret;

> > +    bool is_selftest = false;

> > +    const struct tpm_resp_hdr *hdr = NULL;

> > +    Error *err = NULL;

> > +

> > +    tpm_pt->op_canceled = false;

> > +    tpm_pt->op_executing = true;

> > +    if (selftest_done) {

> > +        *selftest_done = false;

> > +        is_selftest = tpm_util_is_selftest(in, in_len);

> > +    }

> > +

> > +    ret = qio_channel_write(tpm_pt->data_ioc, (char *)in, in_len,

> > &err);

> hmm, too bad qio_channel_write() doesn't take a void *

> 

> why not write_all()?

Agreed
> 

> > 

> > +    if (ret != in_len || err) {

> > +        if (!tpm_pt->op_canceled || errno != ECANCELED) {

> I don't think ECANCELED make sense for emulator code.

> 

> > 

> > +            error_report("tpm-emulator: error while transmitting

> > data "

> > +                         "to TPM: %s", err ? error_get_pretty(err)

> > : "");

> > +            error_free(err);

> > +        }

> > +        goto err_exit;

> > +    }

> > +

> > +    tpm_pt->op_executing = false;

> > +

> > +    ret = qio_channel_read(tpm_pt->data_ioc, (char *)out, out_len,

> > &err);

> > +    if (ret < 0 || err) {

> read_all() ?

The issue with read_all() is it does not return the no of bytes it
read, so i would like to stict to _read()
> 

> > 

> > +        if (!tpm_pt->op_canceled || errno != ECANCELED) {

> > +            error_report("tpm-emulator: error while reading data

> > from "

> > +                         "TPM: %s", err ? error_get_pretty(err) :

> > "");

> > +            error_free(err);

> > +        }

> > +    } else if (ret >= sizeof(*hdr)) {

> > +        hdr = (struct tpm_resp_hdr *)out;

> > +    }

> > +

> > +    if (!hdr || be32_to_cpu(hdr->len) != ret) {

> > +        error_report("tpm-emulator: received invalid response "

> > +                     "packet from TPM with length :%ld", ret);

> > +        ret = -1;

> > +        goto err_exit;

> > +    }

> > +

> > +    if (is_selftest) {

> > +        *selftest_done = (be32_to_cpu(hdr->errcode) == 0);

> > +    }

> > +

> > +    return 0;

> > +

> > +err_exit:

> > +    if (ret < 0) {

> > +        tpm_util_write_fatal_error_response(out, out_len);

> > +    }

> > +

> > +    tpm_pt->op_executing = false;

> > +

> > +    return ret;

> > +}

> > +

> > +static int tpm_emulator_set_locality(TPMEmulator *tpm_pt, uint8_t

> > locty_number)

> > +{

> > +    ptm_loc loc;

> > +

> > +    DPRINTF("%s : locality: 0x%x", __func__, locty_number);

> > +

> > +    if (tpm_pt->cur_locty_number != locty_number) {

> return early instead if ==, to avoid code indent etc

Ok
> 

> > 

> > +        DPRINTF("setting locality : 0x%x", locty_number);

> > +        loc.u.req.loc = locty_number;

> This number isn't set in be like the rest of the protocol?

I doubt if i get ur point :(, can you please elaborate.
> 

> > 

> > +        if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev,

> > CMD_SET_LOCALITY, &loc,

> > +                             sizeof(loc), sizeof(loc)) < 0) {

> > +            error_report("tpm-emulator: could not set locality :

> > %s",

> > +                         strerror(errno));

> > +            return -1;

> > +        }

> > +        loc.u.resp.tpm_result =

> > be32_to_cpu(loc.u.resp.tpm_result);

> > +        if (loc.u.resp.tpm_result != 0) {

> > +            error_report("tpm-emulator: TPM result for set

> > locality : 0x%x",

> > +                         loc.u.resp.tpm_result);

> > +            return -1;

> > +        }

> > +        tpm_pt->cur_locty_number = locty_number;

> > +    }

> > +    return 0;

> > +}

> > +

> > +static void tpm_emulator_handle_request(TPMBackend *tb,

> > TPMBackendCmd cmd)

> > +{

> > +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);

> > +    TPMLocality *locty = NULL;

> > +    bool selftest_done = false;

> > +

> > +    DPRINTF("processing command type %d", cmd);

> > +

> > +    switch (cmd) {

> > +    case TPM_BACKEND_CMD_PROCESS_CMD:

> > +        qemu_mutex_lock(&tpm_pt->state_lock);

> > +        locty = tb->tpm_state->locty_data;

> > +        if (tpm_emulator_set_locality(tpm_pt,

> > +                                      tb->tpm_state->locty_number) 

> > < 0) {

> > +            tpm_util_write_fatal_error_response(locty-

> > >r_buffer.buffer,

> > +                                           locty->r_buffer.size);

> return / goto here instead of else.

We should not retrun from here, we have to propagte the error response
to device, and unlock the state.
> 

> > 

> > +        } else {

> > +            tpm_emulator_unix_tx_bufs(tpm_pt, locty-

> > >w_buffer.buffer,

> > +                                              locty->w_offset,

> > +                                              locty-

> > >r_buffer.buffer,

> > +                                              locty-

> > >r_buffer.size,

> > +                                              &selftest_done);

> no error handling?

The error case is supposed to handle by device, where we are filling
into out buffer, using tpm_util_write_fatal_error_response().
> 

> > 

> > +        }

> > +

> > +        tb->recv_data_callback(tb->tpm_state, tb->tpm_state-

> > >locty_number,

> > +                               selftest_done);

> > +        qemu_mutex_unlock(&tpm_pt->state_lock);

> > +

> > +        break;

> > +    case TPM_BACKEND_CMD_INIT:

> > +    case TPM_BACKEND_CMD_END:

> > +    case TPM_BACKEND_CMD_TPM_RESET:

> > +        /* nothing to do */

> > +        break;

> > +    }

> > +}

> > +

> > +/*

> > + * Gracefully shut down the external unixio TPM

> > + */

> > +static void tpm_emulator_shutdown(TPMEmulator *tpm_pt)

> > +{

> > +    ptm_res res;

> > +

> > +    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_SHUTDOWN,

> > &res, 0,

> > +                         sizeof(res)) < 0) {

> > +        error_report("tpm-emulator: Could not cleanly shutdown the

> > TPM: %s",

> > +                     strerror(errno));

> > +    } else if (res != 0) {

> > +        error_report("tpm-emulator: TPM result for sutdown: 0x%x",

> > +                     be32_to_cpu(res));

> > +    }

> > +}

> > +

> > +static int tpm_emulator_probe_caps(TPMEmulator *tpm_pt)

> > +{

> > +    DPRINTF("%s", __func__);

> > +    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev,

> > CMD_GET_CAPABILITY,

> > +                         &tpm_pt->caps, 0, sizeof(tpm_pt->caps)) <

> > 0) {

> > +        error_report("tpm-emulator: probing failed : %s",

> > strerror(errno));

> > +        return -1;

> > +    }

> > +

> > +    tpm_pt->caps = be64_to_cpu(tpm_pt->caps);

> > +

> > +    DPRINTF("capbilities : 0x%lx", tpm_pt->caps);

> > +

> > +    return 0;

> > +}

> > +

> > +static int tpm_emulator_check_caps(TPMEmulator *tpm_pt)

> > +{

> > +    ptm_cap caps = 0;

> > +    const char *tpm = NULL;

> > +

> > +    /* check for min. required capabilities */

> > +    switch (tpm_pt->tpm_version) {

> > +    case TPM_VERSION_1_2:

> > +        caps = PTM_CAP_INIT | PTM_CAP_SHUTDOWN |

> > PTM_CAP_GET_TPMESTABLISHED |

> > +               PTM_CAP_SET_LOCALITY;

> > +        tpm = "1.2";

> > +        break;

> > +    case TPM_VERSION_2_0:

> > +        caps = PTM_CAP_INIT | PTM_CAP_SHUTDOWN |

> > PTM_CAP_GET_TPMESTABLISHED |

> > +               PTM_CAP_SET_LOCALITY |

> > PTM_CAP_RESET_TPMESTABLISHED;

> > +        tpm = "2";

> > +        break;

> > +    case TPM_VERSION_UNSPEC:

> > +        error_report("tpm-emulator: TPM version has not been

> > set");

> > +        return -1;

> > +    }

> > +

> > +    if (!TPM_EMULATOR_IMPLEMENTS_ALL_CAPS(tpm_pt, caps)) {

> > +        error_report("tpm-emulator: TPM does not implement minimum

> > set of "

> > +                     "required capabilities for TPM %s (0x%x)",

> > tpm, (int)caps);

> > +        return -1;

> > +    }

> > +

> > +    return 0;

> > +}

> > +

> > +static int tpm_emulator_startup_tpm(TPMBackend *tb)

> > +{

> > +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);

> > +    ptm_init init;

> > +    ptm_res res;

> > +

> > +    DPRINTF("%s", __func__);

> > +    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_INIT, &init,

> > sizeof(init),

> > +                         sizeof(init)) < 0) {

> > +        error_report("tpm-emulator: could not send INIT: %s",

> > +                     strerror(errno));

> > +        goto err_exit;

> > +    }

> > +

> > +    res = be32_to_cpu(init.u.resp.tpm_result);

> > +    if (res) {

> > +        error_report("tpm-emulator: TPM result for CMD_INIT:

> > 0x%x", res);

> > +        goto err_exit;

> > +    }

> > +    return 0;

> > +

> > +err_exit:

> > +    tpm_pt->had_startup_error = true;

> > +    return -1;

> > +}

> > +

> > +static bool tpm_emulator_get_tpm_established_flag(TPMBackend *tb)

> > +{

> > +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);

> > +    ptm_est est;

> > +

> > +    DPRINTF("%s", __func__);

> > +    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev,

> > CMD_GET_TPMESTABLISHED, &est, 0,

> > +                         sizeof(est)) < 0) {

> > +        error_report("tpm-emulator: Could not get the TPM

> > established flag: %s",

> > +                     strerror(errno));

> > +        return false;

> > +    }

> > +    DPRINTF("established flag: %0x", est.u.resp.bit);

> > +

> > +    return (est.u.resp.bit != 0);

> > +}

> > +

> > +static int tpm_emulator_reset_tpm_established_flag(TPMBackend *tb,

> > +                                                   uint8_t locty)

> > +{

> > +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);

> > +    ptm_reset_est reset_est;

> > +    ptm_res res;

> > +

> > +    /* only a TPM 2.0 will support this */

> > +    if (tpm_pt->tpm_version == TPM_VERSION_2_0) {

> > +        reset_est.u.req.loc = tpm_pt->cur_locty_number;

> > +

> > +        if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev,

> > CMD_RESET_TPMESTABLISHED,

> > +                                 &reset_est, sizeof(reset_est),

> > +                                 sizeof(reset_est)) < 0) {

> > +            error_report("tpm-emulator: Could not reset the

> > establishment bit: "

> > +                          "%s", strerror(errno));

> > +            return -1;

> > +        }

> > +

> > +        res = be32_to_cpu(reset_est.u.resp.tpm_result);

> > +        if (res) {

> > +            error_report("tpm-emulator: TPM result for rest

> > establixhed flag: "

> > +                         "0x%x", res);

> > +            return -1;

> > +        }

> > +    }

> > +

> > +    return 0;

> > +}

> > +

> > +static bool tpm_emulator_had_startup_error(TPMBackend *tb)

> > +{

> > +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);

> > +

> > +    return tpm_pt->had_startup_error;

> > +}

> > +

> > +static void tpm_emulator_cancel_cmd(TPMBackend *tb)

> > +{

> > +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);

> > +    ptm_res res;

> > +

> > +    /*

> > +     * As of Linux 3.7 the tpm_tis driver does not properly cancel

> > +     * commands on all TPM manufacturers' TPMs.

> > +     * Only cancel if we're busy so we don't cancel someone else's

> > +     * command, e.g., a command executed on the host.

> > +     */

> > +    if (tpm_pt->op_executing) {

> The field is set in the worker thread. This is racy. Fortunately this

> is not relevant for emulator, I think you can simply drop that check

> and the variable. Stefan should confirm though.

> 

> > 

> > +        if (TPM_EMULATOR_IMPLEMENTS_ALL_CAPS(tpm_pt,

> > PTM_CAP_CANCEL_TPM_CMD)) {

> > +            if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev,

> > CMD_CANCEL_TPM_CMD,

> > +                                     &res, 0, sizeof(res)) < 0) {

> > +                error_report("tpm-emulator: Could not cancel

> > command: %s",

> > +                             strerror(errno));

> > +            } else if (res != 0) {

> > +                error_report("tpm-emulator: Failed to cancel TPM:

> > 0x%x",

> > +                             be32_to_cpu(res));

> > +            } else {

> > +                tpm_pt->op_canceled = true;

> > +            }

> > +        }

> > +    }

> > +}

> > +

> > +static void tpm_emulator_reset(TPMBackend *tb)

> > +{

> > +    DPRINTF("%s", __func__);

> > +

> > +    tpm_emulator_cancel_cmd(tb);

> > +}

> > +

> > +static TPMVersion tpm_emulator_get_tpm_version(TPMBackend *tb)

> > +{

> > +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);

> > +

> > +    return tpm_pt->tpm_version;

> > +}

> > +

> > +static void tpm_emulator_block_migration(TPMEmulator *tpm_pt)

> > +{

> > +    Error *err = NULL;

> > +

> > +    error_setg(&tpm_pt->migration_blocker,

> > +               "Migration disabled: TPM emulator not yet

> > migratable");

> > +    migrate_add_blocker(tpm_pt->migration_blocker, &err);

> > +    if (err) {

> > +        error_free(err);

> probably better to report_err it instead

Ok
> 

> > 

> > +        error_free(tpm_pt->migration_blocker);

> > +        tpm_pt->migration_blocker = NULL;

> and return an error code.

Will do
> 

> > 

> > +    }

> > +}

> > +

> > +static int tpm_emulator_prepare_data_fd(TPMEmulator *tpm_pt)

> > +{

> > +    ptm_res res;

> > +    Error *err = NULL;

> > +    int fds[2] = { -1, -1 };

> > +

> > +    if (socketpair(AF_UNIX, SOCK_SEQPACKET, 0, fds) < 0) {

> > +        error_report("tpm-emulator: Failed to create socketpair");

> > +        return -1;

> > +    }

> > +

> > +    qemu_chr_fe_set_msgfds(&tpm_pt->ctrl_dev, fds + 1, 1);

> > +

> > +    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_SET_DATAFD,

> > &res, 0,

> > +                    sizeof(res)) || res != 0) {

> Yay! for making life easier and hiding a protocol detail.

> 

> > 

> > +        error_report("tpm-emulator: Failed to send CMD_SET_DATAFD:

> > %s",

> > +                     strerror(errno));

> > +        goto err_exit;

> > +    }

> > +

> > +    tpm_pt->data_ioc =

> > QIO_CHANNEL(qio_channel_socket_new_fd(fds[0], &err));

> > +    if (err) {

> > +        error_report("tpm-emulator: Failed to create io channel :

> > %s",

> > +                       error_get_pretty(err));

> error_prepend()?

Ok
> 

> > 

> > +        error_free(err);

> > +        goto err_exit;

> > +    }

> close fds[1] ?

I guess we are not supposed to close the other end of the
socketpair/pipe, as it is not forked process.
> 

> > 

> > +

> > +    return 0;

> > +

> > +err_exit:

> > +    closesocket(fds[0]);

> > +    closesocket(fds[1]);

> > +    return -1;

> > +}

> > +

> > +static int tpm_emulator_handle_device_opts(TPMEmulator *tpm_pt,

> > QemuOpts *opts)

> > +{

> > +    const char *value;

> > +

> > +    value = qemu_opt_get(opts, "chardev");

> > +    if (value) {

> > +        Error *err = NULL;

> > +        Chardev *dev = qemu_chr_find(value);

> > +

> > +        tpm_pt->options->chardev = g_strdup(value);

> > +

> > +        if (!dev || !qemu_chr_fe_init(&tpm_pt->ctrl_dev, dev,

> > &err)) {

> > +            error_report("tpm-emulator: No valid chardev found at

> > '%s': %s",

> > +                         value, err ? error_get_pretty(err) : "");

> > +            error_free(err);

> error_prepend

Ok
> 

> > 

> > +            goto err;

> > +        }

> > +    }

> > +

> > +    if (tpm_emulator_prepare_data_fd(tpm_pt) < 0) {

> > +        goto err;

> > +    }

> > +

> > +    /* FIXME: tpm_util_test_tpmdev() accepts only on socket fd, as

> > it also used

> > +     * by passthrough driver, which not yet using GIOChannel.

> > +     */

> > +    if (tpm_util_test_tpmdev(QIO_CHANNEL_SOCKET(tpm_pt->data_ioc)-

> > >fd,

> > +                             &tpm_pt->tpm_version)) {

> > +        error_report("'%s' is not emulating TPM device. Error:

> > %s",

> > +                      tpm_pt->options->chardev, strerror(errno));

> > +        goto err;

> > +    }

> > +

> > +    DPRINTF("TPM Version %s", tpm_pt->tpm_version ==

> > TPM_VERSION_1_2 ? "1.2" :

> > +             (tpm_pt->tpm_version == TPM_VERSION_2_0 ?  "2.0" :

> > "Unspecified"));

> > +

> > +    if (tpm_emulator_probe_caps(tpm_pt) ||

> > +        tpm_emulator_check_caps(tpm_pt)) {

> > +        goto err;

> > +    }

> > +

> > +    tpm_emulator_block_migration(tpm_pt);

> > +

> > +    return 0;

> > +

> > +err:

> > +    DPRINT("Startup error\n");

> > +    return -1;

> > +}

> > +

> > +static TPMBackend *tpm_emulator_create(QemuOpts *opts, const char

> > *id)

> > +{

> > +    TPMBackend *tb = TPM_BACKEND(object_new(TYPE_TPM_EMULATOR));

> > +

> > +    tb->id = g_strdup(id);

> > +

> > +    if (tpm_emulator_handle_device_opts(TPM_EMULATOR(tb), opts)) {

> > +        goto err_exit;

> > +    }

> > +

> > +    return tb;

> > +

> > +err_exit:

> > +    object_unref(OBJECT(tb));

> > +

> > +    return NULL;

> > +}

> > +

> > +static TpmTypeOptions *tpm_emulator_get_tpm_options(TPMBackend

> > *tb)

> > +{

> > +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);

> > +    TpmTypeOptions *options = NULL;

> > +    TPMEmulatorOptions *eoptions = NULL;

> > +

> > +    eoptions = g_new0(TPMEmulatorOptions, 1);

> > +    if (!eoptions) {

> > +        return NULL;

> > +    }

> > +    DPRINTF("%s", __func__);

> > +

> > +    eoptions->chardev = g_strdup(tpm_pt->options->chardev);

> > +    options = g_new0(TpmTypeOptions, 1);

> > +    if (!options) {

> > +        qapi_free_TPMEmulatorOptions(eoptions);

> > +        return NULL;

> > +    }

> > +

> > +    options->type = TPM_TYPE_EMULATOR;

> > +    options->u.emulator.data = eoptions;

> I think this is a job for QAPI_CLONE.

> 

> > 

> > +

> > +    return options;

> > +}

> > +

> > +static const QemuOptDesc tpm_emulator_cmdline_opts[] = {

> > +    TPM_STANDARD_CMDLINE_OPTS,

> > +    {

> > +        .name = "chardev",

> > +        .type = QEMU_OPT_STRING,

> > +        .help = "Character device to use for out-of-band control

> > messages",

> > +    },

> > +    { /* end of list */ },

> > +};

> > +

> > +static const TPMDriverOps tpm_emulator_driver = {

> > +    .type                     = TPM_TYPE_EMULATOR,

> > +    .opts                     = tpm_emulator_cmdline_opts,

> > +    .desc                     = "TPM emulator backend driver",

> > +

> > +    .create                   = tpm_emulator_create,

> > +    .startup_tpm              = tpm_emulator_startup_tpm,

> > +    .reset                    = tpm_emulator_reset,

> > +    .had_startup_error        = tpm_emulator_had_startup_error,

> > +    .cancel_cmd               = tpm_emulator_cancel_cmd,

> > +    .get_tpm_established_flag =

> > tpm_emulator_get_tpm_established_flag,

> > +    .reset_tpm_established_flag =

> > tpm_emulator_reset_tpm_established_flag,

> > +    .get_tpm_version          = tpm_emulator_get_tpm_version,

> > +    .get_tpm_options          = tpm_emulator_get_tpm_options,

> > +};

> > +

> > +static void tpm_emulator_inst_init(Object *obj)

> > +{

> > +    TPMEmulator *tpm_pt = TPM_EMULATOR(obj);

> > +

> > +    DPRINTF("%s", __func__);

> > +    tpm_pt->options = g_new0(TPMEmulatorOptions, 1);

> > +    tpm_pt->op_executing = tpm_pt->op_canceled = false;

> > +    tpm_pt->had_startup_error = false;

> > +    tpm_pt->cur_locty_number = ~0;

> > +    qemu_mutex_init(&tpm_pt->state_lock);

> > +}

> > +

> > +static void tpm_emulator_inst_finalize(Object *obj)

> > +{

> > +    TPMEmulator *tpm_pt = TPM_EMULATOR(obj);

> > +

> > +    tpm_emulator_cancel_cmd(TPM_BACKEND(obj));

> > +    tpm_emulator_shutdown(tpm_pt);

> > +

> > +    if (tpm_pt->data_ioc) {

> > +        qio_channel_close(tpm_pt->data_ioc, NULL);

> > +    }

> > +

> > +    qemu_chr_fe_deinit(&tpm_pt->ctrl_dev, false);

> > +

> > +    if (tpm_pt->options) {

> > +        qapi_free_TPMEmulatorOptions(tpm_pt->options);

> > +    }

> > +

> > +    if (tpm_pt->migration_blocker) {

> > +        migrate_del_blocker(tpm_pt->migration_blocker);

> > +        error_free(tpm_pt->migration_blocker);

> > +    }

> > +}

> > +

> > +static void tpm_emulator_class_init(ObjectClass *klass, void

> > *data)

> > +{

> > +    TPMBackendClass *tbc = TPM_BACKEND_CLASS(klass);

> > +    tbc->ops = &tpm_emulator_driver;

> > +    tbc->handle_request = tpm_emulator_handle_request;

> > +}

> > +

> > +static const TypeInfo tpm_emulator_info = {

> > +    .name = TYPE_TPM_EMULATOR,

> > +    .parent = TYPE_TPM_BACKEND,

> > +    .instance_size = sizeof(TPMEmulator),

> > +    .class_init = tpm_emulator_class_init,

> > +    .instance_init = tpm_emulator_inst_init,

> > +    .instance_finalize = tpm_emulator_inst_finalize,

> > +};

> > +

> > +static void tpm_emulator_register(void)

> > +{

> > +    type_register_static(&tpm_emulator_info);

> > +    tpm_register_driver(&tpm_emulator_driver);

> > +}

> > +

> > +type_init(tpm_emulator_register)

> > diff --git a/hw/tpm/tpm_ioctl.h b/hw/tpm/tpm_ioctl.h

> > new file mode 100644

> > index 0000000..33564b1

> > --- /dev/null

> > +++ b/hw/tpm/tpm_ioctl.h

> This file is copied from swtpm project. Could swtpm have it installed

> on system instead?

> 

> > 

> > @@ -0,0 +1,246 @@

> > +/*

> > + * tpm_ioctl.h

> > + *

> > + * (c) Copyright IBM Corporation 2014, 2015.

> > + *

> > + * This file is licensed under the terms of the 3-clause BSD

> > license

> > + */

> > +#ifndef _TPM_IOCTL_H_

> > +#define _TPM_IOCTL_H_

> > +

> > +#include <stdint.h>

> > +#include <sys/uio.h>

> > +#include <sys/types.h>

> > +#include <sys/ioctl.h>

> > +

> > +/*

> > + * Every response from a command involving a TPM command execution

> > must hold

> > + * the ptm_res as the first element.

> > + * ptm_res corresponds to the error code of a command executed by

> > the TPM.

> > + */

> > +

> > +typedef uint32_t ptm_res;

> > +

> > +/* PTM_GET_TPMESTABLISHED: get the establishment bit */

> > +struct ptm_est {

> > +    union {

> > +        struct {

> > +            ptm_res tpm_result;

> > +            unsigned char bit; /* TPM established bit */

> > +        } resp; /* response */

> > +    } u;

> > +};

> > +

> > +/* PTM_RESET_TPMESTABLISHED: reset establishment bit */

> > +struct ptm_reset_est {

> > +    union {

> > +        struct {

> > +            uint8_t loc; /* locality to use */

> > +        } req; /* request */

> > +        struct {

> > +            ptm_res tpm_result;

> > +        } resp; /* response */

> > +    } u;

> > +};

> > +

> > +/* PTM_INIT */

> > +struct ptm_init {

> > +    union {

> > +        struct {

> > +            uint32_t init_flags; /* see definitions below */

> > +        } req; /* request */

> > +        struct {

> > +            ptm_res tpm_result;

> > +        } resp; /* response */

> > +    } u;

> > +};

> > +

> > +/* above init_flags */

> > +#define PTM_INIT_FLAG_DELETE_VOLATILE (1 << 0)

> > +    /* delete volatile state file after reading it */

> > +

> > +/* PTM_SET_LOCALITY */

> > +struct ptm_loc {

> > +    union {

> > +        struct {

> > +            uint8_t loc; /* locality to set */

> > +        } req; /* request */

> > +        struct {

> > +            ptm_res tpm_result;

> > +        } resp; /* response */

> > +    } u;

> > +};

> > +

> > +/* PTM_HASH_DATA: hash given data */

> > +struct ptm_hdata {

> > +    union {

> > +        struct {

> > +            uint32_t length;

> > +            uint8_t data[4096];

> > +        } req; /* request */

> > +        struct {

> > +            ptm_res tpm_result;

> > +        } resp; /* response */

> > +    } u;

> > +};

> > +

> > +/*

> > + * size of the TPM state blob to transfer; x86_64 can handle 8k,

> > + * ppc64le only ~7k; keep the response below a 4k page size

> > + */

> > +#define PTM_STATE_BLOB_SIZE (3 * 1024)

> > +

> > +/*

> > + * The following is the data structure to get state blobs from the

> > TPM.

> > + * If the size of the state blob exceeds the PTM_STATE_BLOB_SIZE,

> > multiple reads

> > + * with this ioctl and with adjusted offset are necessary. All

> > bytes

> > + * must be transferred and the transfer is done once the last byte

> > has been

> > + * returned.

> > + * It is possible to use the read() interface for reading the

> > data; however, the

> > + * first bytes of the state blob will be part of the response to

> > the ioctl(); a

> > + * subsequent read() is only necessary if the total length

> > (totlength) exceeds

> > + * the number of received bytes. seek() is not supported.

> > + */

> > +struct ptm_getstate {

> > +    union {

> > +        struct {

> > +            uint32_t state_flags; /* may be:

> > PTM_STATE_FLAG_DECRYPTED */

> > +            uint32_t type;        /* which blob to pull */

> > +            uint32_t offset;      /* offset from where to read */

> > +        } req; /* request */

> > +        struct {

> > +            ptm_res tpm_result;

> > +            uint32_t state_flags; /* may be:

> > PTM_STATE_FLAG_ENCRYPTED */

> > +            uint32_t totlength;   /* total length that will be

> > transferred */

> > +            uint32_t length;      /* number of bytes in following

> > buffer */

> > +            uint8_t  data[PTM_STATE_BLOB_SIZE];

> > +        } resp; /* response */

> > +    } u;

> > +};

> > +

> > +/* TPM state blob types */

> > +#define PTM_BLOB_TYPE_PERMANENT  1

> > +#define PTM_BLOB_TYPE_VOLATILE   2

> > +#define PTM_BLOB_TYPE_SAVESTATE  3

> > +

> > +/* state_flags above : */

> > +#define PTM_STATE_FLAG_DECRYPTED     1 /* on input:  get decrypted

> > state */

> > +#define PTM_STATE_FLAG_ENCRYPTED     2 /* on output: state is

> > encrypted */

> > +

> > +/*

> > + * The following is the data structure to set state blobs in the

> > TPM.

> > + * If the size of the state blob exceeds the PTM_STATE_BLOB_SIZE,

> > multiple

> > + * 'writes' using this ioctl are necessary. The last packet is

> > indicated

> > + * by the length being smaller than the PTM_STATE_BLOB_SIZE.

> > + * The very first packet may have a length indicator of '0'

> > enabling

> > + * a write() with all the bytes from a buffer. If the write()

> > interface

> > + * is used, a final ioctl with a non-full buffer must be made to

> > indicate

> > + * that all data were transferred (a write with 0 bytes would not

> > work).

> > + */

> > +struct ptm_setstate {

> > +    union {

> > +        struct {

> > +            uint32_t state_flags; /* may be

> > PTM_STATE_FLAG_ENCRYPTED */

> > +            uint32_t type;        /* which blob to set */

> > +            uint32_t length;      /* length of the data;

> > +                                     use 0 on the first packet to

> > +                                     transfer using write() */

> > +            uint8_t data[PTM_STATE_BLOB_SIZE];

> > +        } req; /* request */

> > +        struct {

> > +            ptm_res tpm_result;

> > +        } resp; /* response */

> > +    } u;

> > +};

> > +

> > +/*

> > + * PTM_GET_CONFIG: Data structure to get runtime configuration

> > information

> > + * such as which keys are applied.

> > + */

> > +struct ptm_getconfig {

> > +    union {

> > +        struct {

> > +            ptm_res tpm_result;

> > +            uint32_t flags;

> > +        } resp; /* response */

> > +    } u;

> > +};

> > +

> > +#define PTM_CONFIG_FLAG_FILE_KEY        0x1

> > +#define PTM_CONFIG_FLAG_MIGRATION_KEY   0x2

> > +

> > +

> > +typedef uint64_t ptm_cap;

> > +typedef struct ptm_est ptm_est;

> > +typedef struct ptm_reset_est ptm_reset_est;

> > +typedef struct ptm_loc ptm_loc;

> > +typedef struct ptm_hdata ptm_hdata;

> > +typedef struct ptm_init ptm_init;

> > +typedef struct ptm_getstate ptm_getstate;

> > +typedef struct ptm_setstate ptm_setstate;

> > +typedef struct ptm_getconfig ptm_getconfig;

> > +

> > +/* capability flags returned by PTM_GET_CAPABILITY */

> > +#define PTM_CAP_INIT               (1)

> > +#define PTM_CAP_SHUTDOWN           (1 << 1)

> > +#define PTM_CAP_GET_TPMESTABLISHED (1 << 2)

> > +#define PTM_CAP_SET_LOCALITY       (1 << 3)

> > +#define PTM_CAP_HASHING            (1 << 4)

> > +#define PTM_CAP_CANCEL_TPM_CMD     (1 << 5)

> > +#define PTM_CAP_STORE_VOLATILE     (1 << 6)

> > +#define PTM_CAP_RESET_TPMESTABLISHED (1 << 7)

> > +#define PTM_CAP_GET_STATEBLOB      (1 << 8)

> > +#define PTM_CAP_SET_STATEBLOB      (1 << 9)

> > +#define PTM_CAP_STOP               (1 << 10)

> > +#define PTM_CAP_GET_CONFIG         (1 << 11)

> > +#define PTM_CAP_SET_DATAFD         (1 << 12)

> > +

> > +enum {

> > +    PTM_GET_CAPABILITY     = _IOR('P', 0, ptm_cap),

> > +    PTM_INIT               = _IOWR('P', 1, ptm_init),

> > +    PTM_SHUTDOWN           = _IOR('P', 2, ptm_res),

> > +    PTM_GET_TPMESTABLISHED = _IOR('P', 3, ptm_est),

> > +    PTM_SET_LOCALITY       = _IOWR('P', 4, ptm_loc),

> > +    PTM_HASH_START         = _IOR('P', 5, ptm_res),

> > +    PTM_HASH_DATA          = _IOWR('P', 6, ptm_hdata),

> > +    PTM_HASH_END           = _IOR('P', 7, ptm_res),

> > +    PTM_CANCEL_TPM_CMD     = _IOR('P', 8, ptm_res),

> > +    PTM_STORE_VOLATILE     = _IOR('P', 9, ptm_res),

> > +    PTM_RESET_TPMESTABLISHED = _IOWR('P', 10, ptm_reset_est),

> > +    PTM_GET_STATEBLOB      = _IOWR('P', 11, ptm_getstate),

> > +    PTM_SET_STATEBLOB      = _IOWR('P', 12, ptm_setstate),

> > +    PTM_STOP               = _IOR('P', 13, ptm_res),

> > +    PTM_GET_CONFIG         = _IOR('P', 14, ptm_getconfig),

> > +    PTM_SET_DATAFD         = _IOR('P', 15, ptm_res),

> > +};

> > +

> > +/*

> > + * Commands used by the non-CUSE TPMs

> > + *

> > + * All messages container big-endian data.

> > + *

> > + * The return messages only contain the 'resp' part of the unions

> > + * in the data structures above. Besides that the limits in the

> > + * buffers above (ptm_hdata:u.req.data and

> > ptm_get_state:u.resp.data

> > + * and ptm_set_state:u.req.data) are 0xffffffff.

> > + */

> > +enum {

> > +    CMD_GET_CAPABILITY = 1,

> > +    CMD_INIT,

> > +    CMD_SHUTDOWN,

> > +    CMD_GET_TPMESTABLISHED,

> > +    CMD_SET_LOCALITY,

> > +    CMD_HASH_START,

> > +    CMD_HASH_DATA,

> > +    CMD_HASH_END,

> > +    CMD_CANCEL_TPM_CMD,

> > +    CMD_STORE_VOLATILE,

> > +    CMD_RESET_TPMESTABLISHED,

> > +    CMD_GET_STATEBLOB,

> > +    CMD_SET_STATEBLOB,

> > +    CMD_STOP,

> > +    CMD_GET_CONFIG,

> > +    CMD_SET_DATAFD

> > +};

> > +

> > +#endif /* _TPM_IOCTL_H */

> > diff --git a/qapi/tpm.json b/qapi/tpm.json

> > index e8b2d8d..7093f26 100644

> > --- a/qapi/tpm.json

> > +++ b/qapi/tpm.json

> > @@ -39,10 +39,12 @@

> >  # An enumeration of TPM types

> >  #

> >  # @passthrough: TPM passthrough type

> > +# @emulator: Software Emulator TPM type

> > +#            Since: 2.11

> >  #

> >  # Since: 1.5

> >  ##

> > -{ 'enum': 'TpmType', 'data': [ 'passthrough' ] }

> > +{ 'enum': 'TpmType', 'data': [ 'passthrough', 'emulator' ] }

> > 

> >  ##

> >  # @query-tpm-types:

> > @@ -56,7 +58,7 @@

> >  # Example:

> >  #

> >  # -> { "execute": "query-tpm-types" }

> > -# <- { "return": [ "passthrough" ] }

> > +# <- { "return": [ "passthrough", "emulator" ] }

> >  #

> >  ##

> >  { 'command': 'query-tpm-types', 'returns': ['TpmType'] }

> > @@ -77,16 +79,29 @@

> >                                               '*cancel-path' :

> > 'str'} }

> > 

> >  ##

> > +# @TPMEmulatorOptions:

> > +#

> > +# Information about the TPM emulator type

> > +#

> > +# @chardev: Name of a unix socket chardev

> > +#

> > +# Since: 2.11

> > +##

> > +{ 'struct': 'TPMEmulatorOptions', 'data': { 'chardev' : 'str' } }

> > +

> > +##

> >  # @TpmTypeOptions:

> >  #

> >  # A union referencing different TPM backend types' configuration

> > options

> >  #

> >  # @type: 'passthrough' The configuration options for the TPM

> > passthrough type

> > +#        'emulator' The configuration options for TPM emulator

> > backend type

> >  #

> >  # Since: 1.5

> >  ##

> >  { 'union': 'TpmTypeOptions',

> > -   'data': { 'passthrough' : 'TPMPassthroughOptions' } }

> > +   'data': { 'passthrough' : 'TPMPassthroughOptions',

> > +             'emulator': 'TPMEmulatorOptions' } }

> > 

> >  ##

> >  # @TPMInfo:

> > diff --git a/qemu-options.hx b/qemu-options.hx

> > index 77859a2..1e93e53 100644

> > --- a/qemu-options.hx

> > +++ b/qemu-options.hx

> > @@ -3121,7 +3121,9 @@ DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \

> >      "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n"

> >      "                use path to provide path to a character

> > device; default is /dev/tpm0\n"

> >      "                use cancel-path to provide path to TPM's

> > cancel sysfs entry; if\n"

> > -    "                not provided it will be searched for in

> > /sys/class/misc/tpm?/device\n",

> > +    "                not provided it will be searched for in

> > /sys/class/misc/tpm?/device\n"

> > +    "-tpmdev emulator,id=id,chardev=dev\n"

> > +    "                configure the TPM device using chardev

> > backend\n",

> >      QEMU_ARCH_ALL)

> >  STEXI

> > 

> > @@ -3130,8 +3132,8 @@ The general form of a TPM device option is:

> > 

> >  @item -tpmdev @var{backend} ,id=@var{id} [,@var{options}]

> >  @findex -tpmdev

> > -Backend type must be:

> > -@option{passthrough}.

> > +Backend type must be either one of the following:

> > +@option{passthrough}, @option{emulator}.

> > 

> >  The specific backend type will determine the applicable options.

> >  The @code{-tpmdev} option creates the TPM backend and requires a

> > @@ -3181,6 +3183,20 @@ To create a passthrough TPM use the

> > following two options:

> >  Note that the @code{-tpmdev} id is @code{tpm0} and is referenced

> > by

> >  @code{tpmdev=tpm0} in the device option.

> > 

> > +@item -tpmdev emulator, id=@var{id}, chardev=@var{dev}

> > +

> > +(Linux-host only) Enable access to a TPM emulator using Unix

> > domain socket based

> > +chardev backend.

> > +

> > +@option{chardev} specifies the unique ID of a character device

> > backend that provides connection to the software TPM server.

> > +

> > +To create a TPM emulator backend device with chardev socket

> > backend:

> > +@example

> > +

> > +-chardev socket,id=chrtpm,path=/tmp/swtpm-ctrl -tpmdev

> > emulator,id=tpm0,chardev=chrtpm -device tpm-tis,tpmdev=tpm0

> > +

> > +@end example

> > +

> >  @end table

> > 

> >  ETEXI

> > --

> > 2.7.4

> > 

> 

> 

- Amarnath

Marc-André Lureau Sept. 26, 2017, 12:24 p.m. UTC | #5

Hi

On Tue, Sep 26, 2017 at 2:05 PM, Valluri, Amarnath
<[e-mail]> wrote:
> Hi Marc,
>
> Thanks for your time reviewing this patchset. Please find my inline
> comments.
>
> On Sun, 2017-09-24 at 20:52 +0200, Marc-André Lureau wrote:
>> Hi
>>
>> Thanks for the nice update, removing the exec() code, using chardev
>> and a private socketpair. Some comments below:
>>
>> On Fri, Sep 22, 2017 at 2:33 PM, Amarnath Valluri
>> <[e-mail]> wrote:
>> >
>> > This change introduces a new TPM backend driver that can
>> > communicate with
>> > swtpm(software TPM emulator) using unix domain socket interface.
>> > QEMU talks to
>> > TPM emulator using socket based chardev backend device.
>> >
>> > Swtpm uses two Unix sockets for communications, one for plain TPM
>> > commands and
>> > responses, and one for out-of-band control messages. QEMU passes
>> > data socket
>> > been used over the control channel.
>> >
>> > The swtpm and associated tools can be found here:
>> >     https://github.com/stefanberger/swtpm
>> >
>> > The swtpm's control channel protocol specification can be found
>> > here:
>> >     https://github.com/stefanberger/swtpm/wiki/Control-Channel-Spec
>> > ification
>> >
>> > Usage:
>> >     # setup TPM state directory
>> >     mkdir /tmp/mytpm
>> >     chown -R tss:root /tmp/mytpm
>> >     /usr/bin/swtpm_setup --tpm-state /tmp/mytpm --createek
>> >
>> >     # Ask qemu to use TPM emulator with given tpm state directory
>> >     qemu-system-x86_64 \
>> >         [...] \
>> >         -chardev socket,id=chrtpm,path=/tmp/swtpm-sock \
>> >         -tpmdev emulator,id=tpm0,chardev=chrtpm \
>> >         -device tpm-tis,tpmdev=tpm0 \
>> >         [...]
>> >
>> > Signed-off-by: Amarnath Valluri <[e-mail]>
>> > ---
>> >  configure             |  15 +-
>> >  hmp.c                 |   5 +
>> >  hw/tpm/Makefile.objs  |   1 +
>> >  hw/tpm/tpm_emulator.c | 649
>> > ++++++++++++++++++++++++++++++++++++++++++++++++++
>> >  hw/tpm/tpm_ioctl.h    | 246 +++++++++++++++++++
>> >  qapi/tpm.json         |  21 +-
>> >  qemu-options.hx       |  22 +-
>> >  7 files changed, 950 insertions(+), 9 deletions(-)
>> >  create mode 100644 hw/tpm/tpm_emulator.c
>> >  create mode 100644 hw/tpm/tpm_ioctl.h
>> >
>> > diff --git a/configure b/configure
>> > index cb0f7ed..ce2df2d 100755
>> > --- a/configure
>> > +++ b/configure
>> > @@ -3461,10 +3461,15 @@ fi
>> >  ##########################################
>> >  # TPM passthrough is only on x86 Linux
>> >
>> > -if test "$targetos" = Linux && test "$cpu" = i386 -o "$cpu" =
>> > x86_64; then
>> > -  tpm_passthrough=$tpm
>> > +if test "$targetos" = Linux; then
>> > +  tpm_emulator=$tpm
>> > +  if test "$cpu" = i386 -o "$cpu" = x86_64; then
>> > +    tpm_passthrough=$tpm
>> > +  else
>> > +    tpm_passthrough=no
>> > +  fi
>> >  else
>> > -  tpm_passthrough=no
>> > +  tpm_emulator=no
>> >  fi
>> >
>> >  ##########################################
>> > @@ -5359,6 +5364,7 @@ echo "gcov enabled      $gcov"
>> >  echo "TPM support       $tpm"
>> >  echo "libssh2 support   $libssh2"
>> >  echo "TPM passthrough   $tpm_passthrough"
>> > +echo "TPM emulator      $tpm_emulator"
>> >  echo "QOM debugging     $qom_cast_debug"
>> >  echo "Live block migration $live_block_migration"
>> >  echo "lzo support       $lzo"
>> > @@ -5943,6 +5949,9 @@ if test "$tpm" = "yes"; then
>> >    if test "$tpm_passthrough" = "yes"; then
>> >      echo "CONFIG_TPM_PASSTHROUGH=y" >> $config_host_mak
>> >    fi
>> > +  if test "$tpm_emulator" = "yes"; then
>> > +    echo "CONFIG_TPM_EMULATOR=y" >> $config_host_mak
>> It shouldn't require Linux, but posix (and I assume a port to other
>> systems isn't impossible). same for build-sys / help / comments.
> I agree, Can you suggest, what is the Qemu way of limiting this to
> 'posix'.
>>

there is CONFIG_POSIX

>> >
>> > +  fi
>> >  fi
>> >
>> >  echo "TRACE_BACKENDS=$trace_backends" >> $config_host_mak
>> > diff --git a/hmp.c b/hmp.c
>> > index cf62b2e..7e69eca 100644
>> > --- a/hmp.c
>> > +++ b/hmp.c
>> > @@ -995,6 +995,7 @@ void hmp_info_tpm(Monitor *mon, const QDict
>> > *qdict)
>> >      Error *err = NULL;
>> >      unsigned int c = 0;
>> >      TPMPassthroughOptions *tpo;
>> > +    TPMEmulatorOptions *teo;
>> >
>> >      info_list = qmp_query_tpm(&err);
>> >      if (err) {
>> > @@ -1024,6 +1025,10 @@ void hmp_info_tpm(Monitor *mon, const QDict
>> > *qdict)
>> >                             tpo->has_cancel_path ? ",cancel-path="
>> > : "",
>> >                             tpo->has_cancel_path ? tpo->cancel_path
>> > : "");
>> >              break;
>> > +        case TPM_TYPE_EMULATOR:
>> > +            teo = ti->options->u.emulator.data;
>> > +            monitor_printf(mon, ",chardev=%s", teo->chardev);
>> > +            break;
>> >          case TPM_TYPE__MAX:
>> >              break;
>> >          }
>> > diff --git a/hw/tpm/Makefile.objs b/hw/tpm/Makefile.objs
>> > index 64cecc3..41f0b7a 100644
>> > --- a/hw/tpm/Makefile.objs
>> > +++ b/hw/tpm/Makefile.objs
>> > @@ -1,2 +1,3 @@
>> >  common-obj-$(CONFIG_TPM_TIS) += tpm_tis.o
>> >  common-obj-$(CONFIG_TPM_PASSTHROUGH) += tpm_passthrough.o
>> > tpm_util.o
>> > +common-obj-$(CONFIG_TPM_EMULATOR) += tpm_emulator.o tpm_util.o
>> > diff --git a/hw/tpm/tpm_emulator.c b/hw/tpm/tpm_emulator.c
>> > new file mode 100644
>> > index 0000000..c02bbe2
>> > --- /dev/null
>> > +++ b/hw/tpm/tpm_emulator.c
>> > @@ -0,0 +1,649 @@
>> > +/*
>> > + *  emulator TPM driver
>> > + *
>> > + *  Copyright (c) 2017 Intel Corporation
>> > + *  Author: Amarnath Valluri <[e-mail]>
>> > + *
>> > + *  Copyright (c) 2010 - 2013 IBM Corporation
>> > + *  Authors:
>> > + *    Stefan Berger <[e-mail]>
>> > + *
>> > + *  Copyright (C) 2011 IAIK, Graz University of Technology
>> > + *    Author: Andreas Niederl
>> > + *
>> > + * This library is free software; you can redistribute it and/or
>> > + * modify it under the terms of the GNU Lesser General Public
>> > + * License as published by the Free Software Foundation; either
>> > + * version 2 of the License, or (at your option) any later
>> > version.
>> > + *
>> > + * This library is distributed in the hope that it will be useful,
>> > + * but WITHOUT ANY WARRANTY; without even the implied warranty of
>> > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
>> > GNU
>> > + * Lesser General Public License for more details.
>> > + *
>> > + * You should have received a copy of the GNU Lesser General
>> > Public
>> > + * License along with this library; if not, see <http://www.gnu.or
>> > g/licenses/>
>> > + *
>> > + */
>> > +
>> > +#include "qemu/osdep.h"
>> > +#include "qemu/error-report.h"
>> > +#include "qemu/sockets.h"
>> > +#include "io/channel-socket.h"
>> > +#include "sysemu/tpm_backend.h"
>> > +#include "tpm_int.h"
>> > +#include "hw/hw.h"
>> > +#include "hw/i386/pc.h"
>> > +#include "tpm_util.h"
>> > +#include "tpm_ioctl.h"
>> > +#include "migration/blocker.h"
>> > +#include "qapi/error.h"
>> > +#include "chardev/char-fe.h"
>> > +
>> > +#include <fcntl.h>
>> > +#include <sys/types.h>
>> > +#include <sys/stat.h>
>> > +#include <stdio.h>
>> > +
>> > +#define DEBUG_TPM 0
>> > +
>> > +#define DPRINT(fmt, ...) do { \
>> > +    if (DEBUG_TPM) { \
>> > +        fprintf(stderr, fmt, ## __VA_ARGS__); \
>> > +    } \
>> > +} while (0);
>> > +
>> > +#define DPRINTF(fmt, ...) DPRINT("tpm-emulator: "fmt"\n",
>> > __VA_ARGS__)
>> I would define a single DPRINTF() (& drop DPRINT usage below)
> Ok, will do
>>
>>
>> >
>> > +
>> > +#define TYPE_TPM_EMULATOR "tpm-emulator"
>> > +#define TPM_EMULATOR(obj) \
>> > +    OBJECT_CHECK(TPMEmulator, (obj), TYPE_TPM_EMULATOR)
>> > +
>> > +#define TPM_EMULATOR_IMPLEMENTS_ALL_CAPS(S, cap) (((S)->caps &
>> > (cap)) == (cap))
>> > +
>> > +static const TPMDriverOps tpm_emulator_driver;
>> > +
>> > +/* data structures */
>> > +typedef struct TPMEmulator {
>> > +    TPMBackend parent;
>> > +
>> > +    TPMEmulatorOptions *options;
>> Contrary to my comment on previous patch, I realize it is convenient
>> to have a qapi pointer here, so you can use the free visitor later.
>>
>> >
>> > +    CharBackend ctrl_dev;
>> ctrl_chr perhaps? or just chr or be (the most common name in other
>> devices).
>>
>> >
>> > +    QIOChannel *data_ioc;
>> > +    bool op_executing;
>> > +    bool op_canceled;
>> I think those 2 fields can be dropped, see below.
>>
>> >
>> > +    bool had_startup_error;
>> I think some little refactoring could remove the whole
>> had_startup_error() backend & callback before or after the series.
>> tpm_backend_startup_tpm() already returns an error code.  device or
>> common backend code could handle & remember that.
> Yes, i agree, we can avoid had_startup_error() from DriverOps, i will
> do this.
>>
>> >
>> > +    TPMVersion tpm_version;
>> This is probably worth to consider in common code instead, but let's
>> not worry about it.
>>
>> >
>> > +    ptm_cap caps; /* capabilities of the TPM */
>> > +    uint8_t cur_locty_number; /* last set locality */
>> > +    QemuMutex state_lock;
>> > +    Error *migration_blocker;
>> > +} TPMEmulator;
>> > +
>> > +
>> > +static int tpm_emulator_ctrlcmd(CharBackend *dev, unsigned long
>> > cmd, void *msg,
>> > +                                size_t msg_len_in, size_t
>> > msg_len_out)
>> > +{
>> > +    uint32_t cmd_no = cpu_to_be32(cmd);
>> > +    ssize_t n = sizeof(uint32_t) + msg_len_in;
>> > +    uint8_t *buf = NULL;
>> > +
>> > +    buf = (uint8_t *)malloc(n);
>> could be g_alloca() instead. Alternatively, why not call 2 write()
>> instead?
>>
>> none of the casts in this function are necessary, please remove them.
> Ok, will change to aclloca()

I just realized this is SOCK_SEQPACKET, ok

>>
>> >
>> > +    memcpy(buf, &cmd_no, sizeof(cmd_no));
>> > +    memcpy(buf + sizeof(cmd_no), msg, msg_len_in);
>> > +
>> > +    n += qemu_chr_fe_write_all(dev, (const uint8_t *)buf, n);
>> weird
>>
>> >
>> > +    free(buf);
>> > +
>> > +    if (n > 0) {
>> with the n += above, you'll get interesting behaviour :)
> Ya, it was typo :)
>>
>> You probably want to check if any write above failed, and return
>> early
>> for the error case.
>>
>> Please improve the error handling in this function
>>
>> >
>> > +        if (msg_len_out > 0) {
>> > +            n = qemu_chr_fe_read_all(dev, (uint8_t *)msg,
>> > msg_len_out);
>> > +            /* simulate ioctl return value */
>> > +            if (n > 0) {
>> > +                n = 0;
>> > +            }
>> > +        } else {
>> > +            n = 0;
>> > +        }
>> > +    }
>> > +    return n;
>> > +}
>> > +
>> > +static int tpm_emulator_unix_tx_bufs(TPMEmulator *tpm_pt,
>> tpm_pt was tpm_passthrough I suppose.
>>
>> Please rename tpm_pt tpm_emu (or I would suggest "self", but this
>> isn't common name in qemu code - it's actually common in a close
>> c-object world., and it is quite convenient...)
> My interpretation about _pt was 'pointer' ;-) i will consider your
> suggetion.
>>
>> >
>> > +                                     const uint8_t *in, uint32_t
>> > in_len,
>> > +                                     uint8_t *out, uint32_t
>> > out_len,
>> > +                                     bool *selftest_done)
>> > +{
>> > +    ssize_t ret;
>> > +    bool is_selftest = false;
>> > +    const struct tpm_resp_hdr *hdr = NULL;
>> > +    Error *err = NULL;
>> > +
>> > +    tpm_pt->op_canceled = false;
>> > +    tpm_pt->op_executing = true;
>> > +    if (selftest_done) {
>> > +        *selftest_done = false;
>> > +        is_selftest = tpm_util_is_selftest(in, in_len);
>> > +    }
>> > +
>> > +    ret = qio_channel_write(tpm_pt->data_ioc, (char *)in, in_len,
>> > &err);
>> hmm, too bad qio_channel_write() doesn't take a void *
>>
>> why not write_all()?
> Agreed
>>
>> >
>> > +    if (ret != in_len || err) {
>> > +        if (!tpm_pt->op_canceled || errno != ECANCELED) {
>> I don't think ECANCELED make sense for emulator code.
>>
>> >
>> > +            error_report("tpm-emulator: error while transmitting
>> > data "
>> > +                         "to TPM: %s", err ? error_get_pretty(err)
>> > : "");
>> > +            error_free(err);
>> > +        }
>> > +        goto err_exit;
>> > +    }
>> > +
>> > +    tpm_pt->op_executing = false;
>> > +
>> > +    ret = qio_channel_read(tpm_pt->data_ioc, (char *)out, out_len,
>> > &err);
>> > +    if (ret < 0 || err) {
>> read_all() ?
> The issue with read_all() is it does not return the no of bytes it
> read, so i would like to stict to _read()

ok

>>
>> >
>> > +        if (!tpm_pt->op_canceled || errno != ECANCELED) {
>> > +            error_report("tpm-emulator: error while reading data
>> > from "
>> > +                         "TPM: %s", err ? error_get_pretty(err) :
>> > "");
>> > +            error_free(err);
>> > +        }
>> > +    } else if (ret >= sizeof(*hdr)) {
>> > +        hdr = (struct tpm_resp_hdr *)out;
>> > +    }
>> > +
>> > +    if (!hdr || be32_to_cpu(hdr->len) != ret) {
>> > +        error_report("tpm-emulator: received invalid response "
>> > +                     "packet from TPM with length :%ld", ret);
>> > +        ret = -1;
>> > +        goto err_exit;
>> > +    }
>> > +
>> > +    if (is_selftest) {
>> > +        *selftest_done = (be32_to_cpu(hdr->errcode) == 0);
>> > +    }
>> > +
>> > +    return 0;
>> > +
>> > +err_exit:
>> > +    if (ret < 0) {
>> > +        tpm_util_write_fatal_error_response(out, out_len);
>> > +    }
>> > +
>> > +    tpm_pt->op_executing = false;
>> > +
>> > +    return ret;
>> > +}
>> > +
>> > +static int tpm_emulator_set_locality(TPMEmulator *tpm_pt, uint8_t
>> > locty_number)
>> > +{
>> > +    ptm_loc loc;
>> > +
>> > +    DPRINTF("%s : locality: 0x%x", __func__, locty_number);
>> > +
>> > +    if (tpm_pt->cur_locty_number != locty_number) {
>> return early instead if ==, to avoid code indent etc
> Ok
>>
>> >
>> > +        DPRINTF("setting locality : 0x%x", locty_number);
>> > +        loc.u.req.loc = locty_number;
>> This number isn't set in be like the rest of the protocol?
> I doubt if i get ur point :(, can you please elaborate.

In the rest of the protocol, it uses big-endian. I suppose you should
cpu_to_be32(locty_number).

>>
>> >
>> > +        if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev,
>> > CMD_SET_LOCALITY, &loc,
>> > +                             sizeof(loc), sizeof(loc)) < 0) {
>> > +            error_report("tpm-emulator: could not set locality :
>> > %s",
>> > +                         strerror(errno));
>> > +            return -1;
>> > +        }
>> > +        loc.u.resp.tpm_result =
>> > be32_to_cpu(loc.u.resp.tpm_result);
>> > +        if (loc.u.resp.tpm_result != 0) {
>> > +            error_report("tpm-emulator: TPM result for set
>> > locality : 0x%x",
>> > +                         loc.u.resp.tpm_result);
>> > +            return -1;
>> > +        }
>> > +        tpm_pt->cur_locty_number = locty_number;
>> > +    }
>> > +    return 0;
>> > +}
>> > +
>> > +static void tpm_emulator_handle_request(TPMBackend *tb,
>> > TPMBackendCmd cmd)
>> > +{
>> > +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
>> > +    TPMLocality *locty = NULL;
>> > +    bool selftest_done = false;
>> > +
>> > +    DPRINTF("processing command type %d", cmd);
>> > +
>> > +    switch (cmd) {
>> > +    case TPM_BACKEND_CMD_PROCESS_CMD:
>> > +        qemu_mutex_lock(&tpm_pt->state_lock);
>> > +        locty = tb->tpm_state->locty_data;
>> > +        if (tpm_emulator_set_locality(tpm_pt,
>> > +                                      tb->tpm_state->locty_number)
>> > < 0) {
>> > +            tpm_util_write_fatal_error_response(locty-
>> > >r_buffer.buffer,
>> > +                                           locty->r_buffer.size);
>> return / goto here instead of else.
> We should not retrun from here, we have to propagte the error response
> to device, and unlock the state.
>>
>> >
>> > +        } else {
>> > +            tpm_emulator_unix_tx_bufs(tpm_pt, locty-
>> > >w_buffer.buffer,
>> > +                                              locty->w_offset,
>> > +                                              locty-
>> > >r_buffer.buffer,
>> > +                                              locty-
>> > >r_buffer.size,
>> > +                                              &selftest_done);
>> no error handling?
> The error case is supposed to handle by device, where we are filling
> into out buffer, using tpm_util_write_fatal_error_response().
>>
>> >
>> > +        }
>> > +
>> > +        tb->recv_data_callback(tb->tpm_state, tb->tpm_state-
>> > >locty_number,
>> > +                               selftest_done);
>> > +        qemu_mutex_unlock(&tpm_pt->state_lock);
>> > +
>> > +        break;
>> > +    case TPM_BACKEND_CMD_INIT:
>> > +    case TPM_BACKEND_CMD_END:
>> > +    case TPM_BACKEND_CMD_TPM_RESET:
>> > +        /* nothing to do */
>> > +        break;
>> > +    }
>> > +}
>> > +
>> > +/*
>> > + * Gracefully shut down the external unixio TPM
>> > + */
>> > +static void tpm_emulator_shutdown(TPMEmulator *tpm_pt)
>> > +{
>> > +    ptm_res res;
>> > +
>> > +    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_SHUTDOWN,
>> > &res, 0,
>> > +                         sizeof(res)) < 0) {
>> > +        error_report("tpm-emulator: Could not cleanly shutdown the
>> > TPM: %s",
>> > +                     strerror(errno));
>> > +    } else if (res != 0) {
>> > +        error_report("tpm-emulator: TPM result for sutdown: 0x%x",
>> > +                     be32_to_cpu(res));
>> > +    }
>> > +}
>> > +
>> > +static int tpm_emulator_probe_caps(TPMEmulator *tpm_pt)
>> > +{
>> > +    DPRINTF("%s", __func__);
>> > +    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev,
>> > CMD_GET_CAPABILITY,
>> > +                         &tpm_pt->caps, 0, sizeof(tpm_pt->caps)) <
>> > 0) {
>> > +        error_report("tpm-emulator: probing failed : %s",
>> > strerror(errno));
>> > +        return -1;
>> > +    }
>> > +
>> > +    tpm_pt->caps = be64_to_cpu(tpm_pt->caps);
>> > +
>> > +    DPRINTF("capbilities : 0x%lx", tpm_pt->caps);
>> > +
>> > +    return 0;
>> > +}
>> > +
>> > +static int tpm_emulator_check_caps(TPMEmulator *tpm_pt)
>> > +{
>> > +    ptm_cap caps = 0;
>> > +    const char *tpm = NULL;
>> > +
>> > +    /* check for min. required capabilities */
>> > +    switch (tpm_pt->tpm_version) {
>> > +    case TPM_VERSION_1_2:
>> > +        caps = PTM_CAP_INIT | PTM_CAP_SHUTDOWN |
>> > PTM_CAP_GET_TPMESTABLISHED |
>> > +               PTM_CAP_SET_LOCALITY;
>> > +        tpm = "1.2";
>> > +        break;
>> > +    case TPM_VERSION_2_0:
>> > +        caps = PTM_CAP_INIT | PTM_CAP_SHUTDOWN |
>> > PTM_CAP_GET_TPMESTABLISHED |
>> > +               PTM_CAP_SET_LOCALITY |
>> > PTM_CAP_RESET_TPMESTABLISHED;
>> > +        tpm = "2";
>> > +        break;
>> > +    case TPM_VERSION_UNSPEC:
>> > +        error_report("tpm-emulator: TPM version has not been
>> > set");
>> > +        return -1;
>> > +    }
>> > +
>> > +    if (!TPM_EMULATOR_IMPLEMENTS_ALL_CAPS(tpm_pt, caps)) {
>> > +        error_report("tpm-emulator: TPM does not implement minimum
>> > set of "
>> > +                     "required capabilities for TPM %s (0x%x)",
>> > tpm, (int)caps);
>> > +        return -1;
>> > +    }
>> > +
>> > +    return 0;
>> > +}
>> > +
>> > +static int tpm_emulator_startup_tpm(TPMBackend *tb)
>> > +{
>> > +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
>> > +    ptm_init init;
>> > +    ptm_res res;
>> > +
>> > +    DPRINTF("%s", __func__);
>> > +    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_INIT, &init,
>> > sizeof(init),
>> > +                         sizeof(init)) < 0) {
>> > +        error_report("tpm-emulator: could not send INIT: %s",
>> > +                     strerror(errno));
>> > +        goto err_exit;
>> > +    }
>> > +
>> > +    res = be32_to_cpu(init.u.resp.tpm_result);
>> > +    if (res) {
>> > +        error_report("tpm-emulator: TPM result for CMD_INIT:
>> > 0x%x", res);
>> > +        goto err_exit;
>> > +    }
>> > +    return 0;
>> > +
>> > +err_exit:
>> > +    tpm_pt->had_startup_error = true;
>> > +    return -1;
>> > +}
>> > +
>> > +static bool tpm_emulator_get_tpm_established_flag(TPMBackend *tb)
>> > +{
>> > +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
>> > +    ptm_est est;
>> > +
>> > +    DPRINTF("%s", __func__);
>> > +    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev,
>> > CMD_GET_TPMESTABLISHED, &est, 0,
>> > +                         sizeof(est)) < 0) {
>> > +        error_report("tpm-emulator: Could not get the TPM
>> > established flag: %s",
>> > +                     strerror(errno));
>> > +        return false;
>> > +    }
>> > +    DPRINTF("established flag: %0x", est.u.resp.bit);
>> > +
>> > +    return (est.u.resp.bit != 0);
>> > +}
>> > +
>> > +static int tpm_emulator_reset_tpm_established_flag(TPMBackend *tb,
>> > +                                                   uint8_t locty)
>> > +{
>> > +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
>> > +    ptm_reset_est reset_est;
>> > +    ptm_res res;
>> > +
>> > +    /* only a TPM 2.0 will support this */
>> > +    if (tpm_pt->tpm_version == TPM_VERSION_2_0) {
>> > +        reset_est.u.req.loc = tpm_pt->cur_locty_number;
>> > +
>> > +        if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev,
>> > CMD_RESET_TPMESTABLISHED,
>> > +                                 &reset_est, sizeof(reset_est),
>> > +                                 sizeof(reset_est)) < 0) {
>> > +            error_report("tpm-emulator: Could not reset the
>> > establishment bit: "
>> > +                          "%s", strerror(errno));
>> > +            return -1;
>> > +        }
>> > +
>> > +        res = be32_to_cpu(reset_est.u.resp.tpm_result);
>> > +        if (res) {
>> > +            error_report("tpm-emulator: TPM result for rest
>> > establixhed flag: "
>> > +                         "0x%x", res);
>> > +            return -1;
>> > +        }
>> > +    }
>> > +
>> > +    return 0;
>> > +}
>> > +
>> > +static bool tpm_emulator_had_startup_error(TPMBackend *tb)
>> > +{
>> > +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
>> > +
>> > +    return tpm_pt->had_startup_error;
>> > +}
>> > +
>> > +static void tpm_emulator_cancel_cmd(TPMBackend *tb)
>> > +{
>> > +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
>> > +    ptm_res res;
>> > +
>> > +    /*
>> > +     * As of Linux 3.7 the tpm_tis driver does not properly cancel
>> > +     * commands on all TPM manufacturers' TPMs.
>> > +     * Only cancel if we're busy so we don't cancel someone else's
>> > +     * command, e.g., a command executed on the host.
>> > +     */
>> > +    if (tpm_pt->op_executing) {
>> The field is set in the worker thread. This is racy. Fortunately this
>> is not relevant for emulator, I think you can simply drop that check
>> and the variable. Stefan should confirm though.
>>
>> >
>> > +        if (TPM_EMULATOR_IMPLEMENTS_ALL_CAPS(tpm_pt,
>> > PTM_CAP_CANCEL_TPM_CMD)) {
>> > +            if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev,
>> > CMD_CANCEL_TPM_CMD,
>> > +                                     &res, 0, sizeof(res)) < 0) {
>> > +                error_report("tpm-emulator: Could not cancel
>> > command: %s",
>> > +                             strerror(errno));
>> > +            } else if (res != 0) {
>> > +                error_report("tpm-emulator: Failed to cancel TPM:
>> > 0x%x",
>> > +                             be32_to_cpu(res));
>> > +            } else {
>> > +                tpm_pt->op_canceled = true;
>> > +            }
>> > +        }
>> > +    }
>> > +}
>> > +
>> > +static void tpm_emulator_reset(TPMBackend *tb)
>> > +{
>> > +    DPRINTF("%s", __func__);
>> > +
>> > +    tpm_emulator_cancel_cmd(tb);
>> > +}
>> > +
>> > +static TPMVersion tpm_emulator_get_tpm_version(TPMBackend *tb)
>> > +{
>> > +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
>> > +
>> > +    return tpm_pt->tpm_version;
>> > +}
>> > +
>> > +static void tpm_emulator_block_migration(TPMEmulator *tpm_pt)
>> > +{
>> > +    Error *err = NULL;
>> > +
>> > +    error_setg(&tpm_pt->migration_blocker,
>> > +               "Migration disabled: TPM emulator not yet
>> > migratable");
>> > +    migrate_add_blocker(tpm_pt->migration_blocker, &err);
>> > +    if (err) {
>> > +        error_free(err);
>> probably better to report_err it instead
> Ok
>>
>> >
>> > +        error_free(tpm_pt->migration_blocker);
>> > +        tpm_pt->migration_blocker = NULL;
>> and return an error code.
> Will do
>>
>> >
>> > +    }
>> > +}
>> > +
>> > +static int tpm_emulator_prepare_data_fd(TPMEmulator *tpm_pt)
>> > +{
>> > +    ptm_res res;
>> > +    Error *err = NULL;
>> > +    int fds[2] = { -1, -1 };
>> > +
>> > +    if (socketpair(AF_UNIX, SOCK_SEQPACKET, 0, fds) < 0) {
>> > +        error_report("tpm-emulator: Failed to create socketpair");
>> > +        return -1;
>> > +    }
>> > +
>> > +    qemu_chr_fe_set_msgfds(&tpm_pt->ctrl_dev, fds + 1, 1);
>> > +
>> > +    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_SET_DATAFD,
>> > &res, 0,
>> > +                    sizeof(res)) || res != 0) {
>> Yay! for making life easier and hiding a protocol detail.
>>
>> >
>> > +        error_report("tpm-emulator: Failed to send CMD_SET_DATAFD:
>> > %s",
>> > +                     strerror(errno));
>> > +        goto err_exit;
>> > +    }
>> > +
>> > +    tpm_pt->data_ioc =
>> > QIO_CHANNEL(qio_channel_socket_new_fd(fds[0], &err));
>> > +    if (err) {
>> > +        error_report("tpm-emulator: Failed to create io channel :
>> > %s",
>> > +                       error_get_pretty(err));
>> error_prepend()?
> Ok
>>
>> >
>> > +        error_free(err);
>> > +        goto err_exit;
>> > +    }
>> close fds[1] ?
> I guess we are not supposed to close the other end of the
> socketpair/pipe, as it is not forked process.

You will close this end, not the other end.

>>
>> >
>> > +
>> > +    return 0;
>> > +
>> > +err_exit:
>> > +    closesocket(fds[0]);
>> > +    closesocket(fds[1]);
>> > +    return -1;
>> > +}
>> > +
>> > +static int tpm_emulator_handle_device_opts(TPMEmulator *tpm_pt,
>> > QemuOpts *opts)
>> > +{
>> > +    const char *value;
>> > +
>> > +    value = qemu_opt_get(opts, "chardev");
>> > +    if (value) {
>> > +        Error *err = NULL;
>> > +        Chardev *dev = qemu_chr_find(value);
>> > +
>> > +        tpm_pt->options->chardev = g_strdup(value);
>> > +
>> > +        if (!dev || !qemu_chr_fe_init(&tpm_pt->ctrl_dev, dev,
>> > &err)) {
>> > +            error_report("tpm-emulator: No valid chardev found at
>> > '%s': %s",
>> > +                         value, err ? error_get_pretty(err) : "");
>> > +            error_free(err);
>> error_prepend
> Ok
>>
>> >
>> > +            goto err;
>> > +        }
>> > +    }
>> > +
>> > +    if (tpm_emulator_prepare_data_fd(tpm_pt) < 0) {
>> > +        goto err;
>> > +    }
>> > +
>> > +    /* FIXME: tpm_util_test_tpmdev() accepts only on socket fd, as
>> > it also used
>> > +     * by passthrough driver, which not yet using GIOChannel.
>> > +     */
>> > +    if (tpm_util_test_tpmdev(QIO_CHANNEL_SOCKET(tpm_pt->data_ioc)-
>> > >fd,
>> > +                             &tpm_pt->tpm_version)) {
>> > +        error_report("'%s' is not emulating TPM device. Error:
>> > %s",
>> > +                      tpm_pt->options->chardev, strerror(errno));
>> > +        goto err;
>> > +    }
>> > +
>> > +    DPRINTF("TPM Version %s", tpm_pt->tpm_version ==
>> > TPM_VERSION_1_2 ? "1.2" :
>> > +             (tpm_pt->tpm_version == TPM_VERSION_2_0 ?  "2.0" :
>> > "Unspecified"));
>> > +
>> > +    if (tpm_emulator_probe_caps(tpm_pt) ||
>> > +        tpm_emulator_check_caps(tpm_pt)) {
>> > +        goto err;
>> > +    }
>> > +
>> > +    tpm_emulator_block_migration(tpm_pt);
>> > +
>> > +    return 0;
>> > +
>> > +err:
>> > +    DPRINT("Startup error\n");
>> > +    return -1;
>> > +}
>> > +
>> > +static TPMBackend *tpm_emulator_create(QemuOpts *opts, const char
>> > *id)
>> > +{
>> > +    TPMBackend *tb = TPM_BACKEND(object_new(TYPE_TPM_EMULATOR));
>> > +
>> > +    tb->id = g_strdup(id);
>> > +
>> > +    if (tpm_emulator_handle_device_opts(TPM_EMULATOR(tb), opts)) {
>> > +        goto err_exit;
>> > +    }
>> > +
>> > +    return tb;
>> > +
>> > +err_exit:
>> > +    object_unref(OBJECT(tb));
>> > +
>> > +    return NULL;
>> > +}
>> > +
>> > +static TpmTypeOptions *tpm_emulator_get_tpm_options(TPMBackend
>> > *tb)
>> > +{
>> > +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
>> > +    TpmTypeOptions *options = NULL;
>> > +    TPMEmulatorOptions *eoptions = NULL;
>> > +
>> > +    eoptions = g_new0(TPMEmulatorOptions, 1);
>> > +    if (!eoptions) {
>> > +        return NULL;
>> > +    }
>> > +    DPRINTF("%s", __func__);
>> > +
>> > +    eoptions->chardev = g_strdup(tpm_pt->options->chardev);
>> > +    options = g_new0(TpmTypeOptions, 1);
>> > +    if (!options) {
>> > +        qapi_free_TPMEmulatorOptions(eoptions);
>> > +        return NULL;
>> > +    }
>> > +
>> > +    options->type = TPM_TYPE_EMULATOR;
>> > +    options->u.emulator.data = eoptions;
>> I think this is a job for QAPI_CLONE.
>>
>> >
>> > +
>> > +    return options;
>> > +}
>> > +
>> > +static const QemuOptDesc tpm_emulator_cmdline_opts[] = {
>> > +    TPM_STANDARD_CMDLINE_OPTS,
>> > +    {
>> > +        .name = "chardev",
>> > +        .type = QEMU_OPT_STRING,
>> > +        .help = "Character device to use for out-of-band control
>> > messages",
>> > +    },
>> > +    { /* end of list */ },
>> > +};
>> > +
>> > +static const TPMDriverOps tpm_emulator_driver = {
>> > +    .type                     = TPM_TYPE_EMULATOR,
>> > +    .opts                     = tpm_emulator_cmdline_opts,
>> > +    .desc                     = "TPM emulator backend driver",
>> > +
>> > +    .create                   = tpm_emulator_create,
>> > +    .startup_tpm              = tpm_emulator_startup_tpm,
>> > +    .reset                    = tpm_emulator_reset,
>> > +    .had_startup_error        = tpm_emulator_had_startup_error,
>> > +    .cancel_cmd               = tpm_emulator_cancel_cmd,
>> > +    .get_tpm_established_flag =
>> > tpm_emulator_get_tpm_established_flag,
>> > +    .reset_tpm_established_flag =
>> > tpm_emulator_reset_tpm_established_flag,
>> > +    .get_tpm_version          = tpm_emulator_get_tpm_version,
>> > +    .get_tpm_options          = tpm_emulator_get_tpm_options,
>> > +};
>> > +
>> > +static void tpm_emulator_inst_init(Object *obj)
>> > +{
>> > +    TPMEmulator *tpm_pt = TPM_EMULATOR(obj);
>> > +
>> > +    DPRINTF("%s", __func__);
>> > +    tpm_pt->options = g_new0(TPMEmulatorOptions, 1);
>> > +    tpm_pt->op_executing = tpm_pt->op_canceled = false;
>> > +    tpm_pt->had_startup_error = false;
>> > +    tpm_pt->cur_locty_number = ~0;
>> > +    qemu_mutex_init(&tpm_pt->state_lock);
>> > +}
>> > +
>> > +static void tpm_emulator_inst_finalize(Object *obj)
>> > +{
>> > +    TPMEmulator *tpm_pt = TPM_EMULATOR(obj);
>> > +
>> > +    tpm_emulator_cancel_cmd(TPM_BACKEND(obj));
>> > +    tpm_emulator_shutdown(tpm_pt);
>> > +
>> > +    if (tpm_pt->data_ioc) {
>> > +        qio_channel_close(tpm_pt->data_ioc, NULL);
>> > +    }
>> > +
>> > +    qemu_chr_fe_deinit(&tpm_pt->ctrl_dev, false);
>> > +
>> > +    if (tpm_pt->options) {
>> > +        qapi_free_TPMEmulatorOptions(tpm_pt->options);
>> > +    }
>> > +
>> > +    if (tpm_pt->migration_blocker) {
>> > +        migrate_del_blocker(tpm_pt->migration_blocker);
>> > +        error_free(tpm_pt->migration_blocker);
>> > +    }
>> > +}
>> > +
>> > +static void tpm_emulator_class_init(ObjectClass *klass, void
>> > *data)
>> > +{
>> > +    TPMBackendClass *tbc = TPM_BACKEND_CLASS(klass);
>> > +    tbc->ops = &tpm_emulator_driver;
>> > +    tbc->handle_request = tpm_emulator_handle_request;
>> > +}
>> > +
>> > +static const TypeInfo tpm_emulator_info = {
>> > +    .name = TYPE_TPM_EMULATOR,
>> > +    .parent = TYPE_TPM_BACKEND,
>> > +    .instance_size = sizeof(TPMEmulator),
>> > +    .class_init = tpm_emulator_class_init,
>> > +    .instance_init = tpm_emulator_inst_init,
>> > +    .instance_finalize = tpm_emulator_inst_finalize,
>> > +};
>> > +
>> > +static void tpm_emulator_register(void)
>> > +{
>> > +    type_register_static(&tpm_emulator_info);
>> > +    tpm_register_driver(&tpm_emulator_driver);
>> > +}
>> > +
>> > +type_init(tpm_emulator_register)
>> > diff --git a/hw/tpm/tpm_ioctl.h b/hw/tpm/tpm_ioctl.h
>> > new file mode 100644
>> > index 0000000..33564b1
>> > --- /dev/null
>> > +++ b/hw/tpm/tpm_ioctl.h
>> This file is copied from swtpm project. Could swtpm have it installed
>> on system instead?
>>
>> >
>> > @@ -0,0 +1,246 @@
>> > +/*
>> > + * tpm_ioctl.h
>> > + *
>> > + * (c) Copyright IBM Corporation 2014, 2015.
>> > + *
>> > + * This file is licensed under the terms of the 3-clause BSD
>> > license
>> > + */
>> > +#ifndef _TPM_IOCTL_H_
>> > +#define _TPM_IOCTL_H_
>> > +
>> > +#include <stdint.h>
>> > +#include <sys/uio.h>
>> > +#include <sys/types.h>
>> > +#include <sys/ioctl.h>
>> > +
>> > +/*
>> > + * Every response from a command involving a TPM command execution
>> > must hold
>> > + * the ptm_res as the first element.
>> > + * ptm_res corresponds to the error code of a command executed by
>> > the TPM.
>> > + */
>> > +
>> > +typedef uint32_t ptm_res;
>> > +
>> > +/* PTM_GET_TPMESTABLISHED: get the establishment bit */
>> > +struct ptm_est {
>> > +    union {
>> > +        struct {
>> > +            ptm_res tpm_result;
>> > +            unsigned char bit; /* TPM established bit */
>> > +        } resp; /* response */
>> > +    } u;
>> > +};
>> > +
>> > +/* PTM_RESET_TPMESTABLISHED: reset establishment bit */
>> > +struct ptm_reset_est {
>> > +    union {
>> > +        struct {
>> > +            uint8_t loc; /* locality to use */
>> > +        } req; /* request */
>> > +        struct {
>> > +            ptm_res tpm_result;
>> > +        } resp; /* response */
>> > +    } u;
>> > +};
>> > +
>> > +/* PTM_INIT */
>> > +struct ptm_init {
>> > +    union {
>> > +        struct {
>> > +            uint32_t init_flags; /* see definitions below */
>> > +        } req; /* request */
>> > +        struct {
>> > +            ptm_res tpm_result;
>> > +        } resp; /* response */
>> > +    } u;
>> > +};
>> > +
>> > +/* above init_flags */
>> > +#define PTM_INIT_FLAG_DELETE_VOLATILE (1 << 0)
>> > +    /* delete volatile state file after reading it */
>> > +
>> > +/* PTM_SET_LOCALITY */
>> > +struct ptm_loc {
>> > +    union {
>> > +        struct {
>> > +            uint8_t loc; /* locality to set */
>> > +        } req; /* request */
>> > +        struct {
>> > +            ptm_res tpm_result;
>> > +        } resp; /* response */
>> > +    } u;
>> > +};
>> > +
>> > +/* PTM_HASH_DATA: hash given data */
>> > +struct ptm_hdata {
>> > +    union {
>> > +        struct {
>> > +            uint32_t length;
>> > +            uint8_t data[4096];
>> > +        } req; /* request */
>> > +        struct {
>> > +            ptm_res tpm_result;
>> > +        } resp; /* response */
>> > +    } u;
>> > +};
>> > +
>> > +/*
>> > + * size of the TPM state blob to transfer; x86_64 can handle 8k,
>> > + * ppc64le only ~7k; keep the response below a 4k page size
>> > + */
>> > +#define PTM_STATE_BLOB_SIZE (3 * 1024)
>> > +
>> > +/*
>> > + * The following is the data structure to get state blobs from the
>> > TPM.
>> > + * If the size of the state blob exceeds the PTM_STATE_BLOB_SIZE,
>> > multiple reads
>> > + * with this ioctl and with adjusted offset are necessary. All
>> > bytes
>> > + * must be transferred and the transfer is done once the last byte
>> > has been
>> > + * returned.
>> > + * It is possible to use the read() interface for reading the
>> > data; however, the
>> > + * first bytes of the state blob will be part of the response to
>> > the ioctl(); a
>> > + * subsequent read() is only necessary if the total length
>> > (totlength) exceeds
>> > + * the number of received bytes. seek() is not supported.
>> > + */
>> > +struct ptm_getstate {
>> > +    union {
>> > +        struct {
>> > +            uint32_t state_flags; /* may be:
>> > PTM_STATE_FLAG_DECRYPTED */
>> > +            uint32_t type;        /* which blob to pull */
>> > +            uint32_t offset;      /* offset from where to read */
>> > +        } req; /* request */
>> > +        struct {
>> > +            ptm_res tpm_result;
>> > +            uint32_t state_flags; /* may be:
>> > PTM_STATE_FLAG_ENCRYPTED */
>> > +            uint32_t totlength;   /* total length that will be
>> > transferred */
>> > +            uint32_t length;      /* number of bytes in following
>> > buffer */
>> > +            uint8_t  data[PTM_STATE_BLOB_SIZE];
>> > +        } resp; /* response */
>> > +    } u;
>> > +};
>> > +
>> > +/* TPM state blob types */
>> > +#define PTM_BLOB_TYPE_PERMANENT  1
>> > +#define PTM_BLOB_TYPE_VOLATILE   2
>> > +#define PTM_BLOB_TYPE_SAVESTATE  3
>> > +
>> > +/* state_flags above : */
>> > +#define PTM_STATE_FLAG_DECRYPTED     1 /* on input:  get decrypted
>> > state */
>> > +#define PTM_STATE_FLAG_ENCRYPTED     2 /* on output: state is
>> > encrypted */
>> > +
>> > +/*
>> > + * The following is the data structure to set state blobs in the
>> > TPM.
>> > + * If the size of the state blob exceeds the PTM_STATE_BLOB_SIZE,
>> > multiple
>> > + * 'writes' using this ioctl are necessary. The last packet is
>> > indicated
>> > + * by the length being smaller than the PTM_STATE_BLOB_SIZE.
>> > + * The very first packet may have a length indicator of '0'
>> > enabling
>> > + * a write() with all the bytes from a buffer. If the write()
>> > interface
>> > + * is used, a final ioctl with a non-full buffer must be made to
>> > indicate
>> > + * that all data were transferred (a write with 0 bytes would not
>> > work).
>> > + */
>> > +struct ptm_setstate {
>> > +    union {
>> > +        struct {
>> > +            uint32_t state_flags; /* may be
>> > PTM_STATE_FLAG_ENCRYPTED */
>> > +            uint32_t type;        /* which blob to set */
>> > +            uint32_t length;      /* length of the data;
>> > +                                     use 0 on the first packet to
>> > +                                     transfer using write() */
>> > +            uint8_t data[PTM_STATE_BLOB_SIZE];
>> > +        } req; /* request */
>> > +        struct {
>> > +            ptm_res tpm_result;
>> > +        } resp; /* response */
>> > +    } u;
>> > +};
>> > +
>> > +/*
>> > + * PTM_GET_CONFIG: Data structure to get runtime configuration
>> > information
>> > + * such as which keys are applied.
>> > + */
>> > +struct ptm_getconfig {
>> > +    union {
>> > +        struct {
>> > +            ptm_res tpm_result;
>> > +            uint32_t flags;
>> > +        } resp; /* response */
>> > +    } u;
>> > +};
>> > +
>> > +#define PTM_CONFIG_FLAG_FILE_KEY        0x1
>> > +#define PTM_CONFIG_FLAG_MIGRATION_KEY   0x2
>> > +
>> > +
>> > +typedef uint64_t ptm_cap;
>> > +typedef struct ptm_est ptm_est;
>> > +typedef struct ptm_reset_est ptm_reset_est;
>> > +typedef struct ptm_loc ptm_loc;
>> > +typedef struct ptm_hdata ptm_hdata;
>> > +typedef struct ptm_init ptm_init;
>> > +typedef struct ptm_getstate ptm_getstate;
>> > +typedef struct ptm_setstate ptm_setstate;
>> > +typedef struct ptm_getconfig ptm_getconfig;
>> > +
>> > +/* capability flags returned by PTM_GET_CAPABILITY */
>> > +#define PTM_CAP_INIT               (1)
>> > +#define PTM_CAP_SHUTDOWN           (1 << 1)
>> > +#define PTM_CAP_GET_TPMESTABLISHED (1 << 2)
>> > +#define PTM_CAP_SET_LOCALITY       (1 << 3)
>> > +#define PTM_CAP_HASHING            (1 << 4)
>> > +#define PTM_CAP_CANCEL_TPM_CMD     (1 << 5)
>> > +#define PTM_CAP_STORE_VOLATILE     (1 << 6)
>> > +#define PTM_CAP_RESET_TPMESTABLISHED (1 << 7)
>> > +#define PTM_CAP_GET_STATEBLOB      (1 << 8)
>> > +#define PTM_CAP_SET_STATEBLOB      (1 << 9)
>> > +#define PTM_CAP_STOP               (1 << 10)
>> > +#define PTM_CAP_GET_CONFIG         (1 << 11)
>> > +#define PTM_CAP_SET_DATAFD         (1 << 12)
>> > +
>> > +enum {
>> > +    PTM_GET_CAPABILITY     = _IOR('P', 0, ptm_cap),
>> > +    PTM_INIT               = _IOWR('P', 1, ptm_init),
>> > +    PTM_SHUTDOWN           = _IOR('P', 2, ptm_res),
>> > +    PTM_GET_TPMESTABLISHED = _IOR('P', 3, ptm_est),
>> > +    PTM_SET_LOCALITY       = _IOWR('P', 4, ptm_loc),
>> > +    PTM_HASH_START         = _IOR('P', 5, ptm_res),
>> > +    PTM_HASH_DATA          = _IOWR('P', 6, ptm_hdata),
>> > +    PTM_HASH_END           = _IOR('P', 7, ptm_res),
>> > +    PTM_CANCEL_TPM_CMD     = _IOR('P', 8, ptm_res),
>> > +    PTM_STORE_VOLATILE     = _IOR('P', 9, ptm_res),
>> > +    PTM_RESET_TPMESTABLISHED = _IOWR('P', 10, ptm_reset_est),
>> > +    PTM_GET_STATEBLOB      = _IOWR('P', 11, ptm_getstate),
>> > +    PTM_SET_STATEBLOB      = _IOWR('P', 12, ptm_setstate),
>> > +    PTM_STOP               = _IOR('P', 13, ptm_res),
>> > +    PTM_GET_CONFIG         = _IOR('P', 14, ptm_getconfig),
>> > +    PTM_SET_DATAFD         = _IOR('P', 15, ptm_res),
>> > +};
>> > +
>> > +/*
>> > + * Commands used by the non-CUSE TPMs
>> > + *
>> > + * All messages container big-endian data.
>> > + *
>> > + * The return messages only contain the 'resp' part of the unions
>> > + * in the data structures above. Besides that the limits in the
>> > + * buffers above (ptm_hdata:u.req.data and
>> > ptm_get_state:u.resp.data
>> > + * and ptm_set_state:u.req.data) are 0xffffffff.
>> > + */
>> > +enum {
>> > +    CMD_GET_CAPABILITY = 1,
>> > +    CMD_INIT,
>> > +    CMD_SHUTDOWN,
>> > +    CMD_GET_TPMESTABLISHED,
>> > +    CMD_SET_LOCALITY,
>> > +    CMD_HASH_START,
>> > +    CMD_HASH_DATA,
>> > +    CMD_HASH_END,
>> > +    CMD_CANCEL_TPM_CMD,
>> > +    CMD_STORE_VOLATILE,
>> > +    CMD_RESET_TPMESTABLISHED,
>> > +    CMD_GET_STATEBLOB,
>> > +    CMD_SET_STATEBLOB,
>> > +    CMD_STOP,
>> > +    CMD_GET_CONFIG,
>> > +    CMD_SET_DATAFD
>> > +};
>> > +
>> > +#endif /* _TPM_IOCTL_H */
>> > diff --git a/qapi/tpm.json b/qapi/tpm.json
>> > index e8b2d8d..7093f26 100644
>> > --- a/qapi/tpm.json
>> > +++ b/qapi/tpm.json
>> > @@ -39,10 +39,12 @@
>> >  # An enumeration of TPM types
>> >  #
>> >  # @passthrough: TPM passthrough type
>> > +# @emulator: Software Emulator TPM type
>> > +#            Since: 2.11
>> >  #
>> >  # Since: 1.5
>> >  ##
>> > -{ 'enum': 'TpmType', 'data': [ 'passthrough' ] }
>> > +{ 'enum': 'TpmType', 'data': [ 'passthrough', 'emulator' ] }
>> >
>> >  ##
>> >  # @query-tpm-types:
>> > @@ -56,7 +58,7 @@
>> >  # Example:
>> >  #
>> >  # -> { "execute": "query-tpm-types" }
>> > -# <- { "return": [ "passthrough" ] }
>> > +# <- { "return": [ "passthrough", "emulator" ] }
>> >  #
>> >  ##
>> >  { 'command': 'query-tpm-types', 'returns': ['TpmType'] }
>> > @@ -77,16 +79,29 @@
>> >                                               '*cancel-path' :
>> > 'str'} }
>> >
>> >  ##
>> > +# @TPMEmulatorOptions:
>> > +#
>> > +# Information about the TPM emulator type
>> > +#
>> > +# @chardev: Name of a unix socket chardev
>> > +#
>> > +# Since: 2.11
>> > +##
>> > +{ 'struct': 'TPMEmulatorOptions', 'data': { 'chardev' : 'str' } }
>> > +
>> > +##
>> >  # @TpmTypeOptions:
>> >  #
>> >  # A union referencing different TPM backend types' configuration
>> > options
>> >  #
>> >  # @type: 'passthrough' The configuration options for the TPM
>> > passthrough type
>> > +#        'emulator' The configuration options for TPM emulator
>> > backend type
>> >  #
>> >  # Since: 1.5
>> >  ##
>> >  { 'union': 'TpmTypeOptions',
>> > -   'data': { 'passthrough' : 'TPMPassthroughOptions' } }
>> > +   'data': { 'passthrough' : 'TPMPassthroughOptions',
>> > +             'emulator': 'TPMEmulatorOptions' } }
>> >
>> >  ##
>> >  # @TPMInfo:
>> > diff --git a/qemu-options.hx b/qemu-options.hx
>> > index 77859a2..1e93e53 100644
>> > --- a/qemu-options.hx
>> > +++ b/qemu-options.hx
>> > @@ -3121,7 +3121,9 @@ DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \
>> >      "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n"
>> >      "                use path to provide path to a character
>> > device; default is /dev/tpm0\n"
>> >      "                use cancel-path to provide path to TPM's
>> > cancel sysfs entry; if\n"
>> > -    "                not provided it will be searched for in
>> > /sys/class/misc/tpm?/device\n",
>> > +    "                not provided it will be searched for in
>> > /sys/class/misc/tpm?/device\n"
>> > +    "-tpmdev emulator,id=id,chardev=dev\n"
>> > +    "                configure the TPM device using chardev
>> > backend\n",
>> >      QEMU_ARCH_ALL)
>> >  STEXI
>> >
>> > @@ -3130,8 +3132,8 @@ The general form of a TPM device option is:
>> >
>> >  @item -tpmdev @var{backend} ,id=@var{id} [,@var{options}]
>> >  @findex -tpmdev
>> > -Backend type must be:
>> > -@option{passthrough}.
>> > +Backend type must be either one of the following:
>> > +@option{passthrough}, @option{emulator}.
>> >
>> >  The specific backend type will determine the applicable options.
>> >  The @code{-tpmdev} option creates the TPM backend and requires a
>> > @@ -3181,6 +3183,20 @@ To create a passthrough TPM use the
>> > following two options:
>> >  Note that the @code{-tpmdev} id is @code{tpm0} and is referenced
>> > by
>> >  @code{tpmdev=tpm0} in the device option.
>> >
>> > +@item -tpmdev emulator, id=@var{id}, chardev=@var{dev}
>> > +
>> > +(Linux-host only) Enable access to a TPM emulator using Unix
>> > domain socket based
>> > +chardev backend.
>> > +
>> > +@option{chardev} specifies the unique ID of a character device
>> > backend that provides connection to the software TPM server.
>> > +
>> > +To create a TPM emulator backend device with chardev socket
>> > backend:
>> > +@example
>> > +
>> > +-chardev socket,id=chrtpm,path=/tmp/swtpm-ctrl -tpmdev
>> > emulator,id=tpm0,chardev=chrtpm -device tpm-tis,tpmdev=tpm0
>> > +
>> > +@end example
>> > +
>> >  @end table
>> >
>> >  ETEXI
>> > --
>> > 2.7.4
>> >
>>
>>
> - Amarnath

Amarnath Valluri Sept. 26, 2017, 1:28 p.m. UTC | #6

On Tue, 2017-09-26 at 14:24 +0200, Marc-André Lureau wrote:
> Hi

> 

> On Tue, Sep 26, 2017 at 2:05 PM, Valluri, Amarnath

> <[e-mail]> wrote:

> > 

> > Hi Marc,

> > 

> > Thanks for your time reviewing this patchset. Please find my inline

> > comments.

> > 

> > On Sun, 2017-09-24 at 20:52 +0200, Marc-André Lureau wrote:

> > > 

> > > Hi

> > > 

> > > Thanks for the nice update, removing the exec() code, using

> > > chardev

> > > and a private socketpair. Some comments below:

> > > 

> > > On Fri, Sep 22, 2017 at 2:33 PM, Amarnath Valluri

> > > <[e-mail]> wrote:

> > > > 

> > > > 

> > > > This change introduces a new TPM backend driver that can

> > > > communicate with

> > > > swtpm(software TPM emulator) using unix domain socket

> > > > interface.

> > > > QEMU talks to

> > > > TPM emulator using socket based chardev backend device.

> > > > 

> > > > Swtpm uses two Unix sockets for communications, one for plain

> > > > TPM

> > > > commands and

> > > > responses, and one for out-of-band control messages. QEMU

> > > > passes

> > > > data socket

> > > > been used over the control channel.

> > > > 

> > > > The swtpm and associated tools can be found here:

> > > >     https://github.com/stefanberger/swtpm

> > > > 

> > > > The swtpm's control channel protocol specification can be found

> > > > here:

> > > >     https://github.com/stefanberger/swtpm/wiki/Control-Channel-

> > > > Spec

> > > > ification

> > > > 

> > > > Usage:

> > > >     # setup TPM state directory

> > > >     mkdir /tmp/mytpm

> > > >     chown -R tss:root /tmp/mytpm

> > > >     /usr/bin/swtpm_setup --tpm-state /tmp/mytpm --createek

> > > > 

> > > >     # Ask qemu to use TPM emulator with given tpm state

> > > > directory

> > > >     qemu-system-x86_64 \

> > > >         [...] \

> > > >         -chardev socket,id=chrtpm,path=/tmp/swtpm-sock \

> > > >         -tpmdev emulator,id=tpm0,chardev=chrtpm \

> > > >         -device tpm-tis,tpmdev=tpm0 \

> > > >         [...]

> > > > 

> > > > Signed-off-by: Amarnath Valluri <[e-mail]>

> > > > ---

> > > >  configure             |  15 +-

> > > >  hmp.c                 |   5 +

> > > >  hw/tpm/Makefile.objs  |   1 +

> > > >  hw/tpm/tpm_emulator.c | 649

> > > > ++++++++++++++++++++++++++++++++++++++++++++++++++

> > > >  hw/tpm/tpm_ioctl.h    | 246 +++++++++++++++++++

> > > >  qapi/tpm.json         |  21 +-

> > > >  qemu-options.hx       |  22 +-

> > > >  7 files changed, 950 insertions(+), 9 deletions(-)

> > > >  create mode 100644 hw/tpm/tpm_emulator.c

> > > >  create mode 100644 hw/tpm/tpm_ioctl.h

> > > > 

> > > > diff --git a/configure b/configure

> > > > index cb0f7ed..ce2df2d 100755

> > > > --- a/configure

> > > > +++ b/configure

> > > > @@ -3461,10 +3461,15 @@ fi

> > > >  ##########################################

> > > >  # TPM passthrough is only on x86 Linux

> > > > 

> > > > -if test "$targetos" = Linux && test "$cpu" = i386 -o "$cpu" =

> > > > x86_64; then

> > > > -  tpm_passthrough=$tpm

> > > > +if test "$targetos" = Linux; then

> > > > +  tpm_emulator=$tpm

> > > > +  if test "$cpu" = i386 -o "$cpu" = x86_64; then

> > > > +    tpm_passthrough=$tpm

> > > > +  else

> > > > +    tpm_passthrough=no

> > > > +  fi

> > > >  else

> > > > -  tpm_passthrough=no

> > > > +  tpm_emulator=no

> > > >  fi

> > > > 

> > > >  ##########################################

> > > > @@ -5359,6 +5364,7 @@ echo "gcov enabled      $gcov"

> > > >  echo "TPM support       $tpm"

> > > >  echo "libssh2 support   $libssh2"

> > > >  echo "TPM passthrough   $tpm_passthrough"

> > > > +echo "TPM emulator      $tpm_emulator"

> > > >  echo "QOM debugging     $qom_cast_debug"

> > > >  echo "Live block migration $live_block_migration"

> > > >  echo "lzo support       $lzo"

> > > > @@ -5943,6 +5949,9 @@ if test "$tpm" = "yes"; then

> > > >    if test "$tpm_passthrough" = "yes"; then

> > > >      echo "CONFIG_TPM_PASSTHROUGH=y" >> $config_host_mak

> > > >    fi

> > > > +  if test "$tpm_emulator" = "yes"; then

> > > > +    echo "CONFIG_TPM_EMULATOR=y" >> $config_host_mak

> > > It shouldn't require Linux, but posix (and I assume a port to

> > > other

> > > systems isn't impossible). same for build-sys / help / comments.

> > I agree, Can you suggest, what is the Qemu way of limiting this to

> > 'posix'.

> > > 

> > > 

> there is CONFIG_POSIX

Ok, thanks. I will check
> 

> > 

> > > 

> > > > 

> > > > 

> > > > +  fi

> > > >  fi

> > > > 

> > > >  echo "TRACE_BACKENDS=$trace_backends" >> $config_host_mak

> > > > diff --git a/hmp.c b/hmp.c

> > > > index cf62b2e..7e69eca 100644

> > > > --- a/hmp.c

> > > > +++ b/hmp.c

> > > > @@ -995,6 +995,7 @@ void hmp_info_tpm(Monitor *mon, const QDict

> > > > *qdict)

> > > >      Error *err = NULL;

> > > >      unsigned int c = 0;

> > > >      TPMPassthroughOptions *tpo;

> > > > +    TPMEmulatorOptions *teo;

> > > > 

> > > >      info_list = qmp_query_tpm(&err);

> > > >      if (err) {

> > > > @@ -1024,6 +1025,10 @@ void hmp_info_tpm(Monitor *mon, const

> > > > QDict

> > > > *qdict)

> > > >                             tpo->has_cancel_path ? ",cancel-

> > > > path="

> > > > : "",

> > > >                             tpo->has_cancel_path ? tpo-

> > > > >cancel_path

> > > > : "");

> > > >              break;

> > > > +        case TPM_TYPE_EMULATOR:

> > > > +            teo = ti->options->u.emulator.data;

> > > > +            monitor_printf(mon, ",chardev=%s", teo->chardev);

> > > > +            break;

> > > >          case TPM_TYPE__MAX:

> > > >              break;

> > > >          }

> > > > diff --git a/hw/tpm/Makefile.objs b/hw/tpm/Makefile.objs

> > > > index 64cecc3..41f0b7a 100644

> > > > --- a/hw/tpm/Makefile.objs

> > > > +++ b/hw/tpm/Makefile.objs

> > > > @@ -1,2 +1,3 @@

> > > >  common-obj-$(CONFIG_TPM_TIS) += tpm_tis.o

> > > >  common-obj-$(CONFIG_TPM_PASSTHROUGH) += tpm_passthrough.o

> > > > tpm_util.o

> > > > +common-obj-$(CONFIG_TPM_EMULATOR) += tpm_emulator.o tpm_util.o

> > > > diff --git a/hw/tpm/tpm_emulator.c b/hw/tpm/tpm_emulator.c

> > > > new file mode 100644

> > > > index 0000000..c02bbe2

> > > > --- /dev/null

> > > > +++ b/hw/tpm/tpm_emulator.c

> > > > @@ -0,0 +1,649 @@

> > > > +/*

> > > > + *  emulator TPM driver

> > > > + *

> > > > + *  Copyright (c) 2017 Intel Corporation

> > > > + *  Author: Amarnath Valluri <[e-mail]>

> > > > + *

> > > > + *  Copyright (c) 2010 - 2013 IBM Corporation

> > > > + *  Authors:

> > > > + *    Stefan Berger <[e-mail]>

> > > > + *

> > > > + *  Copyright (C) 2011 IAIK, Graz University of Technology

> > > > + *    Author: Andreas Niederl

> > > > + *

> > > > + * This library is free software; you can redistribute it

> > > > and/or

> > > > + * modify it under the terms of the GNU Lesser General Public

> > > > + * License as published by the Free Software Foundation;

> > > > either

> > > > + * version 2 of the License, or (at your option) any later

> > > > version.

> > > > + *

> > > > + * This library is distributed in the hope that it will be

> > > > useful,

> > > > + * but WITHOUT ANY WARRANTY; without even the implied warranty

> > > > of

> > > > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See

> > > > the

> > > > GNU

> > > > + * Lesser General Public License for more details.

> > > > + *

> > > > + * You should have received a copy of the GNU Lesser General

> > > > Public

> > > > + * License along with this library; if not, see <http://www.gn

> > > > u.or

> > > > g/licenses/>

> > > > + *

> > > > + */

> > > > +

> > > > +#include "qemu/osdep.h"

> > > > +#include "qemu/error-report.h"

> > > > +#include "qemu/sockets.h"

> > > > +#include "io/channel-socket.h"

> > > > +#include "sysemu/tpm_backend.h"

> > > > +#include "tpm_int.h"

> > > > +#include "hw/hw.h"

> > > > +#include "hw/i386/pc.h"

> > > > +#include "tpm_util.h"

> > > > +#include "tpm_ioctl.h"

> > > > +#include "migration/blocker.h"

> > > > +#include "qapi/error.h"

> > > > +#include "chardev/char-fe.h"

> > > > +

> > > > +#include <fcntl.h>

> > > > +#include <sys/types.h>

> > > > +#include <sys/stat.h>

> > > > +#include <stdio.h>

> > > > +

> > > > +#define DEBUG_TPM 0

> > > > +

> > > > +#define DPRINT(fmt, ...) do { \

> > > > +    if (DEBUG_TPM) { \

> > > > +        fprintf(stderr, fmt, ## __VA_ARGS__); \

> > > > +    } \

> > > > +} while (0);

> > > > +

> > > > +#define DPRINTF(fmt, ...) DPRINT("tpm-emulator: "fmt"\n",

> > > > __VA_ARGS__)

> > > I would define a single DPRINTF() (& drop DPRINT usage below)

> > Ok, will do

> > > 

> > > 

> > > 

> > > > 

> > > > 

> > > > +

> > > > +#define TYPE_TPM_EMULATOR "tpm-emulator"

> > > > +#define TPM_EMULATOR(obj) \

> > > > +    OBJECT_CHECK(TPMEmulator, (obj), TYPE_TPM_EMULATOR)

> > > > +

> > > > +#define TPM_EMULATOR_IMPLEMENTS_ALL_CAPS(S, cap) (((S)->caps &

> > > > (cap)) == (cap))

> > > > +

> > > > +static const TPMDriverOps tpm_emulator_driver;

> > > > +

> > > > +/* data structures */

> > > > +typedef struct TPMEmulator {

> > > > +    TPMBackend parent;

> > > > +

> > > > +    TPMEmulatorOptions *options;

> > > Contrary to my comment on previous patch, I realize it is

> > > convenient

> > > to have a qapi pointer here, so you can use the free visitor

> > > later.

> > > 

> > > > 

> > > > 

> > > > +    CharBackend ctrl_dev;

> > > ctrl_chr perhaps? or just chr or be (the most common name in

> > > other

> > > devices).

> > > 

> > > > 

> > > > 

> > > > +    QIOChannel *data_ioc;

> > > > +    bool op_executing;

> > > > +    bool op_canceled;

> > > I think those 2 fields can be dropped, see below.

> > > 

> > > > 

> > > > 

> > > > +    bool had_startup_error;

> > > I think some little refactoring could remove the whole

> > > had_startup_error() backend & callback before or after the

> > > series.

> > > tpm_backend_startup_tpm() already returns an error code.  device

> > > or

> > > common backend code could handle & remember that.

> > Yes, i agree, we can avoid had_startup_error() from DriverOps, i

> > will

> > do this.

> > > 

> > > 

> > > > 

> > > > 

> > > > +    TPMVersion tpm_version;

> > > This is probably worth to consider in common code instead, but

> > > let's

> > > not worry about it.

> > > 

> > > > 

> > > > 

> > > > +    ptm_cap caps; /* capabilities of the TPM */

> > > > +    uint8_t cur_locty_number; /* last set locality */

> > > > +    QemuMutex state_lock;

> > > > +    Error *migration_blocker;

> > > > +} TPMEmulator;

> > > > +

> > > > +

> > > > +static int tpm_emulator_ctrlcmd(CharBackend *dev, unsigned

> > > > long

> > > > cmd, void *msg,

> > > > +                                size_t msg_len_in, size_t

> > > > msg_len_out)

> > > > +{

> > > > +    uint32_t cmd_no = cpu_to_be32(cmd);

> > > > +    ssize_t n = sizeof(uint32_t) + msg_len_in;

> > > > +    uint8_t *buf = NULL;

> > > > +

> > > > +    buf = (uint8_t *)malloc(n);

> > > could be g_alloca() instead. Alternatively, why not call 2

> > > write()

> > > instead?

> > > 

> > > none of the casts in this function are necessary, please remove

> > > them.

> > Ok, will change to aclloca()

> I just realized this is SOCK_SEQPACKET, ok

> 

> > 

> > > 

> > > 

> > > > 

> > > > 

> > > > +    memcpy(buf, &cmd_no, sizeof(cmd_no));

> > > > +    memcpy(buf + sizeof(cmd_no), msg, msg_len_in);

> > > > +

> > > > +    n += qemu_chr_fe_write_all(dev, (const uint8_t *)buf, n);

> > > weird

> > > 

> > > > 

> > > > 

> > > > +    free(buf);

> > > > +

> > > > +    if (n > 0) {

> > > with the n += above, you'll get interesting behaviour :)

> > Ya, it was typo :)

> > > 

> > > 

> > > You probably want to check if any write above failed, and return

> > > early

> > > for the error case.

> > > 

> > > Please improve the error handling in this function

> > > 

> > > > 

> > > > 

> > > > +        if (msg_len_out > 0) {

> > > > +            n = qemu_chr_fe_read_all(dev, (uint8_t *)msg,

> > > > msg_len_out);

> > > > +            /* simulate ioctl return value */

> > > > +            if (n > 0) {

> > > > +                n = 0;

> > > > +            }

> > > > +        } else {

> > > > +            n = 0;

> > > > +        }

> > > > +    }

> > > > +    return n;

> > > > +}

> > > > +

> > > > +static int tpm_emulator_unix_tx_bufs(TPMEmulator *tpm_pt,

> > > tpm_pt was tpm_passthrough I suppose.

> > > 

> > > Please rename tpm_pt tpm_emu (or I would suggest "self", but this

> > > isn't common name in qemu code - it's actually common in a close

> > > c-object world., and it is quite convenient...)

> > My interpretation about _pt was 'pointer' ;-) i will consider your

> > suggetion.

> > > 

> > > 

> > > > 

> > > > 

> > > > +                                     const uint8_t *in,

> > > > uint32_t

> > > > in_len,

> > > > +                                     uint8_t *out, uint32_t

> > > > out_len,

> > > > +                                     bool *selftest_done)

> > > > +{

> > > > +    ssize_t ret;

> > > > +    bool is_selftest = false;

> > > > +    const struct tpm_resp_hdr *hdr = NULL;

> > > > +    Error *err = NULL;

> > > > +

> > > > +    tpm_pt->op_canceled = false;

> > > > +    tpm_pt->op_executing = true;

> > > > +    if (selftest_done) {

> > > > +        *selftest_done = false;

> > > > +        is_selftest = tpm_util_is_selftest(in, in_len);

> > > > +    }

> > > > +

> > > > +    ret = qio_channel_write(tpm_pt->data_ioc, (char *)in,

> > > > in_len,

> > > > &err);

> > > hmm, too bad qio_channel_write() doesn't take a void *

> > > 

> > > why not write_all()?

> > Agreed

> > > 

> > > 

> > > > 

> > > > 

> > > > +    if (ret != in_len || err) {

> > > > +        if (!tpm_pt->op_canceled || errno != ECANCELED) {

> > > I don't think ECANCELED make sense for emulator code.

> > > 

> > > > 

> > > > 

> > > > +            error_report("tpm-emulator: error while

> > > > transmitting

> > > > data "

> > > > +                         "to TPM: %s", err ?

> > > > error_get_pretty(err)

> > > > : "");

> > > > +            error_free(err);

> > > > +        }

> > > > +        goto err_exit;

> > > > +    }

> > > > +

> > > > +    tpm_pt->op_executing = false;

> > > > +

> > > > +    ret = qio_channel_read(tpm_pt->data_ioc, (char *)out,

> > > > out_len,

> > > > &err);

> > > > +    if (ret < 0 || err) {

> > > read_all() ?

> > The issue with read_all() is it does not return the no of bytes it

> > read, so i would like to stict to _read()

> ok

> 

> > 

> > > 

> > > 

> > > > 

> > > > 

> > > > +        if (!tpm_pt->op_canceled || errno != ECANCELED) {

> > > > +            error_report("tpm-emulator: error while reading

> > > > data

> > > > from "

> > > > +                         "TPM: %s", err ?

> > > > error_get_pretty(err) :

> > > > "");

> > > > +            error_free(err);

> > > > +        }

> > > > +    } else if (ret >= sizeof(*hdr)) {

> > > > +        hdr = (struct tpm_resp_hdr *)out;

> > > > +    }

> > > > +

> > > > +    if (!hdr || be32_to_cpu(hdr->len) != ret) {

> > > > +        error_report("tpm-emulator: received invalid response

> > > > "

> > > > +                     "packet from TPM with length :%ld", ret);

> > > > +        ret = -1;

> > > > +        goto err_exit;

> > > > +    }

> > > > +

> > > > +    if (is_selftest) {

> > > > +        *selftest_done = (be32_to_cpu(hdr->errcode) == 0);

> > > > +    }

> > > > +

> > > > +    return 0;

> > > > +

> > > > +err_exit:

> > > > +    if (ret < 0) {

> > > > +        tpm_util_write_fatal_error_response(out, out_len);

> > > > +    }

> > > > +

> > > > +    tpm_pt->op_executing = false;

> > > > +

> > > > +    return ret;

> > > > +}

> > > > +

> > > > +static int tpm_emulator_set_locality(TPMEmulator *tpm_pt,

> > > > uint8_t

> > > > locty_number)

> > > > +{

> > > > +    ptm_loc loc;

> > > > +

> > > > +    DPRINTF("%s : locality: 0x%x", __func__, locty_number);

> > > > +

> > > > +    if (tpm_pt->cur_locty_number != locty_number) {

> > > return early instead if ==, to avoid code indent etc

> > Ok

> > > 

> > > 

> > > > 

> > > > 

> > > > +        DPRINTF("setting locality : 0x%x", locty_number);

> > > > +        loc.u.req.loc = locty_number;

> > > This number isn't set in be like the rest of the protocol?

> > I doubt if i get ur point :(, can you please elaborate.

> In the rest of the protocol, it uses big-endian. I suppose you should

> cpu_to_be32(locty_number).

> 

> > 

> > > 

> > > 

> > > > 

> > > > 

> > > > +        if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev,

> > > > CMD_SET_LOCALITY, &loc,

> > > > +                             sizeof(loc), sizeof(loc)) < 0) {

> > > > +            error_report("tpm-emulator: could not set locality

> > > > :

> > > > %s",

> > > > +                         strerror(errno));

> > > > +            return -1;

> > > > +        }

> > > > +        loc.u.resp.tpm_result =

> > > > be32_to_cpu(loc.u.resp.tpm_result);

> > > > +        if (loc.u.resp.tpm_result != 0) {

> > > > +            error_report("tpm-emulator: TPM result for set

> > > > locality : 0x%x",

> > > > +                         loc.u.resp.tpm_result);

> > > > +            return -1;

> > > > +        }

> > > > +        tpm_pt->cur_locty_number = locty_number;

> > > > +    }

> > > > +    return 0;

> > > > +}

> > > > +

> > > > +static void tpm_emulator_handle_request(TPMBackend *tb,

> > > > TPMBackendCmd cmd)

> > > > +{

> > > > +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);

> > > > +    TPMLocality *locty = NULL;

> > > > +    bool selftest_done = false;

> > > > +

> > > > +    DPRINTF("processing command type %d", cmd);

> > > > +

> > > > +    switch (cmd) {

> > > > +    case TPM_BACKEND_CMD_PROCESS_CMD:

> > > > +        qemu_mutex_lock(&tpm_pt->state_lock);

> > > > +        locty = tb->tpm_state->locty_data;

> > > > +        if (tpm_emulator_set_locality(tpm_pt,

> > > > +                                      tb->tpm_state-

> > > > >locty_number)

> > > > < 0) {

> > > > +            tpm_util_write_fatal_error_response(locty-

> > > > > 

> > > > > r_buffer.buffer,

> > > > +                                           locty-

> > > > >r_buffer.size);

> > > return / goto here instead of else.

> > We should not retrun from here, we have to propagte the error

> > response

> > to device, and unlock the state.

> > > 

> > > 

> > > > 

> > > > 

> > > > +        } else {

> > > > +            tpm_emulator_unix_tx_bufs(tpm_pt, locty-

> > > > > 

> > > > > w_buffer.buffer,

> > > > +                                              locty->w_offset,

> > > > +                                              locty-

> > > > > 

> > > > > r_buffer.buffer,

> > > > +                                              locty-

> > > > > 

> > > > > r_buffer.size,

> > > > +                                              &selftest_done);

> > > no error handling?

> > The error case is supposed to handle by device, where we are

> > filling

> > into out buffer, using tpm_util_write_fatal_error_response().

> > > 

> > > 

> > > > 

> > > > 

> > > > +        }

> > > > +

> > > > +        tb->recv_data_callback(tb->tpm_state, tb->tpm_state-

> > > > > 

> > > > > locty_number,

> > > > +                               selftest_done);

> > > > +        qemu_mutex_unlock(&tpm_pt->state_lock);

> > > > +

> > > > +        break;

> > > > +    case TPM_BACKEND_CMD_INIT:

> > > > +    case TPM_BACKEND_CMD_END:

> > > > +    case TPM_BACKEND_CMD_TPM_RESET:

> > > > +        /* nothing to do */

> > > > +        break;

> > > > +    }

> > > > +}

> > > > +

> > > > +/*

> > > > + * Gracefully shut down the external unixio TPM

> > > > + */

> > > > +static void tpm_emulator_shutdown(TPMEmulator *tpm_pt)

> > > > +{

> > > > +    ptm_res res;

> > > > +

> > > > +    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_SHUTDOWN,

> > > > &res, 0,

> > > > +                         sizeof(res)) < 0) {

> > > > +        error_report("tpm-emulator: Could not cleanly shutdown

> > > > the

> > > > TPM: %s",

> > > > +                     strerror(errno));

> > > > +    } else if (res != 0) {

> > > > +        error_report("tpm-emulator: TPM result for sutdown:

> > > > 0x%x",

> > > > +                     be32_to_cpu(res));

> > > > +    }

> > > > +}

> > > > +

> > > > +static int tpm_emulator_probe_caps(TPMEmulator *tpm_pt)

> > > > +{

> > > > +    DPRINTF("%s", __func__);

> > > > +    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev,

> > > > CMD_GET_CAPABILITY,

> > > > +                         &tpm_pt->caps, 0, sizeof(tpm_pt-

> > > > >caps)) <

> > > > 0) {

> > > > +        error_report("tpm-emulator: probing failed : %s",

> > > > strerror(errno));

> > > > +        return -1;

> > > > +    }

> > > > +

> > > > +    tpm_pt->caps = be64_to_cpu(tpm_pt->caps);

> > > > +

> > > > +    DPRINTF("capbilities : 0x%lx", tpm_pt->caps);

> > > > +

> > > > +    return 0;

> > > > +}

> > > > +

> > > > +static int tpm_emulator_check_caps(TPMEmulator *tpm_pt)

> > > > +{

> > > > +    ptm_cap caps = 0;

> > > > +    const char *tpm = NULL;

> > > > +

> > > > +    /* check for min. required capabilities */

> > > > +    switch (tpm_pt->tpm_version) {

> > > > +    case TPM_VERSION_1_2:

> > > > +        caps = PTM_CAP_INIT | PTM_CAP_SHUTDOWN |

> > > > PTM_CAP_GET_TPMESTABLISHED |

> > > > +               PTM_CAP_SET_LOCALITY;

> > > > +        tpm = "1.2";

> > > > +        break;

> > > > +    case TPM_VERSION_2_0:

> > > > +        caps = PTM_CAP_INIT | PTM_CAP_SHUTDOWN |

> > > > PTM_CAP_GET_TPMESTABLISHED |

> > > > +               PTM_CAP_SET_LOCALITY |

> > > > PTM_CAP_RESET_TPMESTABLISHED;

> > > > +        tpm = "2";

> > > > +        break;

> > > > +    case TPM_VERSION_UNSPEC:

> > > > +        error_report("tpm-emulator: TPM version has not been

> > > > set");

> > > > +        return -1;

> > > > +    }

> > > > +

> > > > +    if (!TPM_EMULATOR_IMPLEMENTS_ALL_CAPS(tpm_pt, caps)) {

> > > > +        error_report("tpm-emulator: TPM does not implement

> > > > minimum

> > > > set of "

> > > > +                     "required capabilities for TPM %s

> > > > (0x%x)",

> > > > tpm, (int)caps);

> > > > +        return -1;

> > > > +    }

> > > > +

> > > > +    return 0;

> > > > +}

> > > > +

> > > > +static int tpm_emulator_startup_tpm(TPMBackend *tb)

> > > > +{

> > > > +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);

> > > > +    ptm_init init;

> > > > +    ptm_res res;

> > > > +

> > > > +    DPRINTF("%s", __func__);

> > > > +    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_INIT,

> > > > &init,

> > > > sizeof(init),

> > > > +                         sizeof(init)) < 0) {

> > > > +        error_report("tpm-emulator: could not send INIT: %s",

> > > > +                     strerror(errno));

> > > > +        goto err_exit;

> > > > +    }

> > > > +

> > > > +    res = be32_to_cpu(init.u.resp.tpm_result);

> > > > +    if (res) {

> > > > +        error_report("tpm-emulator: TPM result for CMD_INIT:

> > > > 0x%x", res);

> > > > +        goto err_exit;

> > > > +    }

> > > > +    return 0;

> > > > +

> > > > +err_exit:

> > > > +    tpm_pt->had_startup_error = true;

> > > > +    return -1;

> > > > +}

> > > > +

> > > > +static bool tpm_emulator_get_tpm_established_flag(TPMBackend

> > > > *tb)

> > > > +{

> > > > +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);

> > > > +    ptm_est est;

> > > > +

> > > > +    DPRINTF("%s", __func__);

> > > > +    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev,

> > > > CMD_GET_TPMESTABLISHED, &est, 0,

> > > > +                         sizeof(est)) < 0) {

> > > > +        error_report("tpm-emulator: Could not get the TPM

> > > > established flag: %s",

> > > > +                     strerror(errno));

> > > > +        return false;

> > > > +    }

> > > > +    DPRINTF("established flag: %0x", est.u.resp.bit);

> > > > +

> > > > +    return (est.u.resp.bit != 0);

> > > > +}

> > > > +

> > > > +static int tpm_emulator_reset_tpm_established_flag(TPMBackend

> > > > *tb,

> > > > +                                                   uint8_t

> > > > locty)

> > > > +{

> > > > +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);

> > > > +    ptm_reset_est reset_est;

> > > > +    ptm_res res;

> > > > +

> > > > +    /* only a TPM 2.0 will support this */

> > > > +    if (tpm_pt->tpm_version == TPM_VERSION_2_0) {

> > > > +        reset_est.u.req.loc = tpm_pt->cur_locty_number;

> > > > +

> > > > +        if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev,

> > > > CMD_RESET_TPMESTABLISHED,

> > > > +                                 &reset_est,

> > > > sizeof(reset_est),

> > > > +                                 sizeof(reset_est)) < 0) {

> > > > +            error_report("tpm-emulator: Could not reset the

> > > > establishment bit: "

> > > > +                          "%s", strerror(errno));

> > > > +            return -1;

> > > > +        }

> > > > +

> > > > +        res = be32_to_cpu(reset_est.u.resp.tpm_result);

> > > > +        if (res) {

> > > > +            error_report("tpm-emulator: TPM result for rest

> > > > establixhed flag: "

> > > > +                         "0x%x", res);

> > > > +            return -1;

> > > > +        }

> > > > +    }

> > > > +

> > > > +    return 0;

> > > > +}

> > > > +

> > > > +static bool tpm_emulator_had_startup_error(TPMBackend *tb)

> > > > +{

> > > > +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);

> > > > +

> > > > +    return tpm_pt->had_startup_error;

> > > > +}

> > > > +

> > > > +static void tpm_emulator_cancel_cmd(TPMBackend *tb)

> > > > +{

> > > > +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);

> > > > +    ptm_res res;

> > > > +

> > > > +    /*

> > > > +     * As of Linux 3.7 the tpm_tis driver does not properly

> > > > cancel

> > > > +     * commands on all TPM manufacturers' TPMs.

> > > > +     * Only cancel if we're busy so we don't cancel someone

> > > > else's

> > > > +     * command, e.g., a command executed on the host.

> > > > +     */

> > > > +    if (tpm_pt->op_executing) {

> > > The field is set in the worker thread. This is racy. Fortunately

> > > this

> > > is not relevant for emulator, I think you can simply drop that

> > > check

> > > and the variable. Stefan should confirm though.

> > > 

> > > > 

> > > > 

> > > > +        if (TPM_EMULATOR_IMPLEMENTS_ALL_CAPS(tpm_pt,

> > > > PTM_CAP_CANCEL_TPM_CMD)) {

> > > > +            if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev,

> > > > CMD_CANCEL_TPM_CMD,

> > > > +                                     &res, 0, sizeof(res)) <

> > > > 0) {

> > > > +                error_report("tpm-emulator: Could not cancel

> > > > command: %s",

> > > > +                             strerror(errno));

> > > > +            } else if (res != 0) {

> > > > +                error_report("tpm-emulator: Failed to cancel

> > > > TPM:

> > > > 0x%x",

> > > > +                             be32_to_cpu(res));

> > > > +            } else {

> > > > +                tpm_pt->op_canceled = true;

> > > > +            }

> > > > +        }

> > > > +    }

> > > > +}

> > > > +

> > > > +static void tpm_emulator_reset(TPMBackend *tb)

> > > > +{

> > > > +    DPRINTF("%s", __func__);

> > > > +

> > > > +    tpm_emulator_cancel_cmd(tb);

> > > > +}

> > > > +

> > > > +static TPMVersion tpm_emulator_get_tpm_version(TPMBackend *tb)

> > > > +{

> > > > +    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);

> > > > +

> > > > +    return tpm_pt->tpm_version;

> > > > +}

> > > > +

> > > > +static void tpm_emulator_block_migration(TPMEmulator *tpm_pt)

> > > > +{

> > > > +    Error *err = NULL;

> > > > +

> > > > +    error_setg(&tpm_pt->migration_blocker,

> > > > +               "Migration disabled: TPM emulator not yet

> > > > migratable");

> > > > +    migrate_add_blocker(tpm_pt->migration_blocker, &err);

> > > > +    if (err) {

> > > > +        error_free(err);

> > > probably better to report_err it instead

> > Ok

> > > 

> > > 

> > > > 

> > > > 

> > > > +        error_free(tpm_pt->migration_blocker);

> > > > +        tpm_pt->migration_blocker = NULL;

> > > and return an error code.

> > Will do

> > > 

> > > 

> > > > 

> > > > 

> > > > +    }

> > > > +}

> > > > +

> > > > +static int tpm_emulator_prepare_data_fd(TPMEmulator *tpm_pt)

> > > > +{

> > > > +    ptm_res res;

> > > > +    Error *err = NULL;

> > > > +    int fds[2] = { -1, -1 };

> > > > +

> > > > +    if (socketpair(AF_UNIX, SOCK_SEQPACKET, 0, fds) < 0) {

> > > > +        error_report("tpm-emulator: Failed to create

> > > > socketpair");

> > > > +        return -1;

> > > > +    }

> > > > +

> > > > +    qemu_chr_fe_set_msgfds(&tpm_pt->ctrl_dev, fds + 1, 1);

> > > > +

> > > > +    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev,

> > > > CMD_SET_DATAFD,

> > > > &res, 0,

> > > > +                    sizeof(res)) || res != 0) {

> > > Yay! for making life easier and hiding a protocol detail.

> > > 

> > > > 

> > > > 

> > > > +        error_report("tpm-emulator: Failed to send

> > > > CMD_SET_DATAFD:

> > > > %s",

> > > > +                     strerror(errno));

> > > > +        goto err_exit;

> > > > +    }

> > > > +

> > > > +    tpm_pt->data_ioc =

> > > > QIO_CHANNEL(qio_channel_socket_new_fd(fds[0], &err));

> > > > +    if (err) {

> > > > +        error_report("tpm-emulator: Failed to create io

> > > > channel :

> > > > %s",

> > > > +                       error_get_pretty(err));

> > > error_prepend()?

> > Ok

> > > 

> > > 

> > > > 

> > > > 

> > > > +        error_free(err);

> > > > +        goto err_exit;

> > > > +    }

> > > close fds[1] ?

> > I guess we are not supposed to close the other end of the

> > socketpair/pipe, as it is not forked process.

> You will close this end, not the other end.

fds[1] is handed over to other end, fds[0] is used by qemu, so we
cannot close unless error case i guess.

- Amarnath

Marc-André Lureau Sept. 26, 2017, 1:55 p.m. UTC | #7

Hi

On Tue, Sep 26, 2017 at 3:28 PM, Valluri, Amarnath
<[e-mail]> wrote:
> On Tue, 2017-09-26 at 14:24 +0200, Marc-André Lureau wrote:
>> > > close fds[1] ?
>> > I guess we are not supposed to close the other end of the
>> > socketpair/pipe, as it is not forked process.
>> You will close this end, not the other end.
> fds[1] is handed over to other end, fds[0] is used by qemu, so we
> cannot close unless error case i guess.

You should be able to close fds[1] in qemu, and keep the communication
working between the two processes. If you don't close, it will leak a
fd in qemu.

Eric Blake Sept. 26, 2017, 1:59 p.m. UTC | #8

On 09/26/2017 07:05 AM, Valluri, Amarnath wrote:

>>> +
>>> +#define DPRINT(fmt, ...) do { \
>>> +    if (DEBUG_TPM) { \
>>> +        fprintf(stderr, fmt, ## __VA_ARGS__); \
>>> +    } \
>>> +} while (0);

Do not include the trailing ';' directly in the macro definition. The
whole point of wrapping things in a do{}while(0) is so that you can do:

if (foo)
    DPRINT(...);
else
    ...

(of course, that violates our coding style, as we require {} everywhere,
but it makes your macro appropriate for copying and pasting to other
projects that have different styles).


>>> +    ret = qio_channel_read(tpm_pt->data_ioc, (char *)out, out_len,
>>> &err);
>>> +    if (ret < 0 || err) {
>> read_all() ?
> The issue with read_all() is it does not return the no of bytes it
> read, so i would like to stict to _read()

But you KNOW the number of bytes read if read_all() succeeded - it read
as many bytes as you requested!

Patch

diff --git a/configure b/configure
index cb0f7ed..ce2df2d 100755
--- a/configure
+++ b/configure
@@ -3461,10 +3461,15 @@  fi
 ##########################################
 # TPM passthrough is only on x86 Linux
 
-if test "$targetos" = Linux && test "$cpu" = i386 -o "$cpu" = x86_64; then
-  tpm_passthrough=$tpm
+if test "$targetos" = Linux; then
+  tpm_emulator=$tpm
+  if test "$cpu" = i386 -o "$cpu" = x86_64; then
+    tpm_passthrough=$tpm
+  else
+    tpm_passthrough=no
+  fi
 else
-  tpm_passthrough=no
+  tpm_emulator=no
 fi
 
 ##########################################
@@ -5359,6 +5364,7 @@  echo "gcov enabled      $gcov"
 echo "TPM support       $tpm"
 echo "libssh2 support   $libssh2"
 echo "TPM passthrough   $tpm_passthrough"
+echo "TPM emulator      $tpm_emulator"
 echo "QOM debugging     $qom_cast_debug"
 echo "Live block migration $live_block_migration"
 echo "lzo support       $lzo"
@@ -5943,6 +5949,9 @@  if test "$tpm" = "yes"; then
   if test "$tpm_passthrough" = "yes"; then
     echo "CONFIG_TPM_PASSTHROUGH=y" >> $config_host_mak
   fi
+  if test "$tpm_emulator" = "yes"; then
+    echo "CONFIG_TPM_EMULATOR=y" >> $config_host_mak
+  fi
 fi
 
 echo "TRACE_BACKENDS=$trace_backends" >> $config_host_mak
diff --git a/hmp.c b/hmp.c
index cf62b2e..7e69eca 100644
--- a/hmp.c
+++ b/hmp.c
@@ -995,6 +995,7 @@  void hmp_info_tpm(Monitor *mon, const QDict *qdict)
     Error *err = NULL;
     unsigned int c = 0;
     TPMPassthroughOptions *tpo;
+    TPMEmulatorOptions *teo;
 
     info_list = qmp_query_tpm(&err);
     if (err) {
@@ -1024,6 +1025,10 @@  void hmp_info_tpm(Monitor *mon, const QDict *qdict)
                            tpo->has_cancel_path ? ",cancel-path=" : "",
                            tpo->has_cancel_path ? tpo->cancel_path : "");
             break;
+        case TPM_TYPE_EMULATOR:
+            teo = ti->options->u.emulator.data;
+            monitor_printf(mon, ",chardev=%s", teo->chardev);
+            break;
         case TPM_TYPE__MAX:
             break;
         }
diff --git a/hw/tpm/Makefile.objs b/hw/tpm/Makefile.objs
index 64cecc3..41f0b7a 100644
--- a/hw/tpm/Makefile.objs
+++ b/hw/tpm/Makefile.objs
@@ -1,2 +1,3 @@ 
 common-obj-$(CONFIG_TPM_TIS) += tpm_tis.o
 common-obj-$(CONFIG_TPM_PASSTHROUGH) += tpm_passthrough.o tpm_util.o
+common-obj-$(CONFIG_TPM_EMULATOR) += tpm_emulator.o tpm_util.o
diff --git a/hw/tpm/tpm_emulator.c b/hw/tpm/tpm_emulator.c
new file mode 100644
index 0000000..c02bbe2
--- /dev/null
+++ b/hw/tpm/tpm_emulator.c
@@ -0,0 +1,649 @@ 
+/*
+ *  emulator TPM driver
+ *
+ *  Copyright (c) 2017 Intel Corporation
+ *  Author: Amarnath Valluri <[e-mail]>
+ *
+ *  Copyright (c) 2010 - 2013 IBM Corporation
+ *  Authors:
+ *    Stefan Berger <[e-mail]>
+ *
+ *  Copyright (C) 2011 IAIK, Graz University of Technology
+ *    Author: Andreas Niederl
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/error-report.h"
+#include "qemu/sockets.h"
+#include "io/channel-socket.h"
+#include "sysemu/tpm_backend.h"
+#include "tpm_int.h"
+#include "hw/hw.h"
+#include "hw/i386/pc.h"
+#include "tpm_util.h"
+#include "tpm_ioctl.h"
+#include "migration/blocker.h"
+#include "qapi/error.h"
+#include "chardev/char-fe.h"
+
+#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <stdio.h>
+
+#define DEBUG_TPM 0
+
+#define DPRINT(fmt, ...) do { \
+    if (DEBUG_TPM) { \
+        fprintf(stderr, fmt, ## __VA_ARGS__); \
+    } \
+} while (0);
+
+#define DPRINTF(fmt, ...) DPRINT("tpm-emulator: "fmt"\n", __VA_ARGS__)
+
+#define TYPE_TPM_EMULATOR "tpm-emulator"
+#define TPM_EMULATOR(obj) \
+    OBJECT_CHECK(TPMEmulator, (obj), TYPE_TPM_EMULATOR)
+
+#define TPM_EMULATOR_IMPLEMENTS_ALL_CAPS(S, cap) (((S)->caps & (cap)) == (cap))
+
+static const TPMDriverOps tpm_emulator_driver;
+
+/* data structures */
+typedef struct TPMEmulator {
+    TPMBackend parent;
+
+    TPMEmulatorOptions *options;
+    CharBackend ctrl_dev;
+    QIOChannel *data_ioc;
+    bool op_executing;
+    bool op_canceled;
+    bool had_startup_error;
+    TPMVersion tpm_version;
+    ptm_cap caps; /* capabilities of the TPM */
+    uint8_t cur_locty_number; /* last set locality */
+    QemuMutex state_lock;
+    Error *migration_blocker;
+} TPMEmulator;
+
+
+static int tpm_emulator_ctrlcmd(CharBackend *dev, unsigned long cmd, void *msg,
+                                size_t msg_len_in, size_t msg_len_out)
+{
+    uint32_t cmd_no = cpu_to_be32(cmd);
+    ssize_t n = sizeof(uint32_t) + msg_len_in;
+    uint8_t *buf = NULL;
+
+    buf = (uint8_t *)malloc(n);
+    memcpy(buf, &cmd_no, sizeof(cmd_no));
+    memcpy(buf + sizeof(cmd_no), msg, msg_len_in);
+
+    n += qemu_chr_fe_write_all(dev, (const uint8_t *)buf, n);
+    free(buf);
+
+    if (n > 0) {
+        if (msg_len_out > 0) {
+            n = qemu_chr_fe_read_all(dev, (uint8_t *)msg, msg_len_out);
+            /* simulate ioctl return value */
+            if (n > 0) {
+                n = 0;
+            }
+        } else {
+            n = 0;
+        }
+    }
+    return n;
+}
+
+static int tpm_emulator_unix_tx_bufs(TPMEmulator *tpm_pt,
+                                     const uint8_t *in, uint32_t in_len,
+                                     uint8_t *out, uint32_t out_len,
+                                     bool *selftest_done)
+{
+    ssize_t ret;
+    bool is_selftest = false;
+    const struct tpm_resp_hdr *hdr = NULL;
+    Error *err = NULL;
+
+    tpm_pt->op_canceled = false;
+    tpm_pt->op_executing = true;
+    if (selftest_done) {
+        *selftest_done = false;
+        is_selftest = tpm_util_is_selftest(in, in_len);
+    }
+
+    ret = qio_channel_write(tpm_pt->data_ioc, (char *)in, in_len, &err);
+    if (ret != in_len || err) {
+        if (!tpm_pt->op_canceled || errno != ECANCELED) {
+            error_report("tpm-emulator: error while transmitting data "
+                         "to TPM: %s", err ? error_get_pretty(err) : "");
+            error_free(err);
+        }
+        goto err_exit;
+    }
+
+    tpm_pt->op_executing = false;
+
+    ret = qio_channel_read(tpm_pt->data_ioc, (char *)out, out_len, &err);
+    if (ret < 0 || err) {
+        if (!tpm_pt->op_canceled || errno != ECANCELED) {
+            error_report("tpm-emulator: error while reading data from "
+                         "TPM: %s", err ? error_get_pretty(err) : "");
+            error_free(err);
+        }
+    } else if (ret >= sizeof(*hdr)) {
+        hdr = (struct tpm_resp_hdr *)out;
+    }
+
+    if (!hdr || be32_to_cpu(hdr->len) != ret) {
+        error_report("tpm-emulator: received invalid response "
+                     "packet from TPM with length :%ld", ret);
+        ret = -1;
+        goto err_exit;
+    }
+
+    if (is_selftest) {
+        *selftest_done = (be32_to_cpu(hdr->errcode) == 0);
+    }
+
+    return 0;
+
+err_exit:
+    if (ret < 0) {
+        tpm_util_write_fatal_error_response(out, out_len);
+    }
+
+    tpm_pt->op_executing = false;
+
+    return ret;
+}
+
+static int tpm_emulator_set_locality(TPMEmulator *tpm_pt, uint8_t locty_number)
+{
+    ptm_loc loc;
+
+    DPRINTF("%s : locality: 0x%x", __func__, locty_number);
+
+    if (tpm_pt->cur_locty_number != locty_number) {
+        DPRINTF("setting locality : 0x%x", locty_number);
+        loc.u.req.loc = locty_number;
+        if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_SET_LOCALITY, &loc,
+                             sizeof(loc), sizeof(loc)) < 0) {
+            error_report("tpm-emulator: could not set locality : %s",
+                         strerror(errno));
+            return -1;
+        }
+        loc.u.resp.tpm_result = be32_to_cpu(loc.u.resp.tpm_result);
+        if (loc.u.resp.tpm_result != 0) {
+            error_report("tpm-emulator: TPM result for set locality : 0x%x",
+                         loc.u.resp.tpm_result);
+            return -1;
+        }
+        tpm_pt->cur_locty_number = locty_number;
+    }
+    return 0;
+}
+
+static void tpm_emulator_handle_request(TPMBackend *tb, TPMBackendCmd cmd)
+{
+    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
+    TPMLocality *locty = NULL;
+    bool selftest_done = false;
+
+    DPRINTF("processing command type %d", cmd);
+
+    switch (cmd) {
+    case TPM_BACKEND_CMD_PROCESS_CMD:
+        qemu_mutex_lock(&tpm_pt->state_lock);
+        locty = tb->tpm_state->locty_data;
+        if (tpm_emulator_set_locality(tpm_pt,
+                                      tb->tpm_state->locty_number) < 0) {
+            tpm_util_write_fatal_error_response(locty->r_buffer.buffer,
+                                           locty->r_buffer.size);
+        } else {
+            tpm_emulator_unix_tx_bufs(tpm_pt, locty->w_buffer.buffer,
+                                              locty->w_offset,
+                                              locty->r_buffer.buffer,
+                                              locty->r_buffer.size,
+                                              &selftest_done);
+        }
+
+        tb->recv_data_callback(tb->tpm_state, tb->tpm_state->locty_number,
+                               selftest_done);
+        qemu_mutex_unlock(&tpm_pt->state_lock);
+
+        break;
+    case TPM_BACKEND_CMD_INIT:
+    case TPM_BACKEND_CMD_END:
+    case TPM_BACKEND_CMD_TPM_RESET:
+        /* nothing to do */
+        break;
+    }
+}
+
+/*
+ * Gracefully shut down the external unixio TPM
+ */
+static void tpm_emulator_shutdown(TPMEmulator *tpm_pt)
+{
+    ptm_res res;
+
+    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_SHUTDOWN, &res, 0,
+                         sizeof(res)) < 0) {
+        error_report("tpm-emulator: Could not cleanly shutdown the TPM: %s",
+                     strerror(errno));
+    } else if (res != 0) {
+        error_report("tpm-emulator: TPM result for sutdown: 0x%x",
+                     be32_to_cpu(res));
+    }
+}
+
+static int tpm_emulator_probe_caps(TPMEmulator *tpm_pt)
+{
+    DPRINTF("%s", __func__);
+    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_GET_CAPABILITY,
+                         &tpm_pt->caps, 0, sizeof(tpm_pt->caps)) < 0) {
+        error_report("tpm-emulator: probing failed : %s", strerror(errno));
+        return -1;
+    }
+
+    tpm_pt->caps = be64_to_cpu(tpm_pt->caps);
+
+    DPRINTF("capbilities : 0x%lx", tpm_pt->caps);
+
+    return 0;
+}
+
+static int tpm_emulator_check_caps(TPMEmulator *tpm_pt)
+{
+    ptm_cap caps = 0;
+    const char *tpm = NULL;
+
+    /* check for min. required capabilities */
+    switch (tpm_pt->tpm_version) {
+    case TPM_VERSION_1_2:
+        caps = PTM_CAP_INIT | PTM_CAP_SHUTDOWN | PTM_CAP_GET_TPMESTABLISHED |
+               PTM_CAP_SET_LOCALITY;
+        tpm = "1.2";
+        break;
+    case TPM_VERSION_2_0:
+        caps = PTM_CAP_INIT | PTM_CAP_SHUTDOWN | PTM_CAP_GET_TPMESTABLISHED |
+               PTM_CAP_SET_LOCALITY | PTM_CAP_RESET_TPMESTABLISHED;
+        tpm = "2";
+        break;
+    case TPM_VERSION_UNSPEC:
+        error_report("tpm-emulator: TPM version has not been set");
+        return -1;
+    }
+
+    if (!TPM_EMULATOR_IMPLEMENTS_ALL_CAPS(tpm_pt, caps)) {
+        error_report("tpm-emulator: TPM does not implement minimum set of "
+                     "required capabilities for TPM %s (0x%x)", tpm, (int)caps);
+        return -1;
+    }
+
+    return 0;
+}
+
+static int tpm_emulator_startup_tpm(TPMBackend *tb)
+{
+    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
+    ptm_init init;
+    ptm_res res;
+
+    DPRINTF("%s", __func__);
+    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_INIT, &init, sizeof(init),
+                         sizeof(init)) < 0) {
+        error_report("tpm-emulator: could not send INIT: %s",
+                     strerror(errno));
+        goto err_exit;
+    }
+
+    res = be32_to_cpu(init.u.resp.tpm_result);
+    if (res) {
+        error_report("tpm-emulator: TPM result for CMD_INIT: 0x%x", res);
+        goto err_exit;
+    }
+    return 0;
+
+err_exit:
+    tpm_pt->had_startup_error = true;
+    return -1;
+}
+
+static bool tpm_emulator_get_tpm_established_flag(TPMBackend *tb)
+{
+    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
+    ptm_est est;
+
+    DPRINTF("%s", __func__);
+    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_GET_TPMESTABLISHED, &est, 0,
+                         sizeof(est)) < 0) {
+        error_report("tpm-emulator: Could not get the TPM established flag: %s",
+                     strerror(errno));
+        return false;
+    }
+    DPRINTF("established flag: %0x", est.u.resp.bit);
+
+    return (est.u.resp.bit != 0);
+}
+
+static int tpm_emulator_reset_tpm_established_flag(TPMBackend *tb,
+                                                   uint8_t locty)
+{
+    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
+    ptm_reset_est reset_est;
+    ptm_res res;
+
+    /* only a TPM 2.0 will support this */
+    if (tpm_pt->tpm_version == TPM_VERSION_2_0) {
+        reset_est.u.req.loc = tpm_pt->cur_locty_number;
+
+        if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_RESET_TPMESTABLISHED,
+                                 &reset_est, sizeof(reset_est),
+                                 sizeof(reset_est)) < 0) {
+            error_report("tpm-emulator: Could not reset the establishment bit: "
+                          "%s", strerror(errno));
+            return -1;
+        }
+
+        res = be32_to_cpu(reset_est.u.resp.tpm_result);
+        if (res) {
+            error_report("tpm-emulator: TPM result for rest establixhed flag: "
+                         "0x%x", res);
+            return -1;
+        }
+    }
+
+    return 0;
+}
+
+static bool tpm_emulator_had_startup_error(TPMBackend *tb)
+{
+    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
+
+    return tpm_pt->had_startup_error;
+}
+
+static void tpm_emulator_cancel_cmd(TPMBackend *tb)
+{
+    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
+    ptm_res res;
+
+    /*
+     * As of Linux 3.7 the tpm_tis driver does not properly cancel
+     * commands on all TPM manufacturers' TPMs.
+     * Only cancel if we're busy so we don't cancel someone else's
+     * command, e.g., a command executed on the host.
+     */
+    if (tpm_pt->op_executing) {
+        if (TPM_EMULATOR_IMPLEMENTS_ALL_CAPS(tpm_pt, PTM_CAP_CANCEL_TPM_CMD)) {
+            if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_CANCEL_TPM_CMD,
+                                     &res, 0, sizeof(res)) < 0) {
+                error_report("tpm-emulator: Could not cancel command: %s",
+                             strerror(errno));
+            } else if (res != 0) {
+                error_report("tpm-emulator: Failed to cancel TPM: 0x%x",
+                             be32_to_cpu(res));
+            } else {
+                tpm_pt->op_canceled = true;
+            }
+        }
+    }
+}
+
+static void tpm_emulator_reset(TPMBackend *tb)
+{
+    DPRINTF("%s", __func__);
+
+    tpm_emulator_cancel_cmd(tb);
+}
+
+static TPMVersion tpm_emulator_get_tpm_version(TPMBackend *tb)
+{
+    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
+
+    return tpm_pt->tpm_version;
+}
+
+static void tpm_emulator_block_migration(TPMEmulator *tpm_pt)
+{
+    Error *err = NULL;
+
+    error_setg(&tpm_pt->migration_blocker,
+               "Migration disabled: TPM emulator not yet migratable");
+    migrate_add_blocker(tpm_pt->migration_blocker, &err);
+    if (err) {
+        error_free(err);
+        error_free(tpm_pt->migration_blocker);
+        tpm_pt->migration_blocker = NULL;
+    }
+}
+
+static int tpm_emulator_prepare_data_fd(TPMEmulator *tpm_pt)
+{
+    ptm_res res;
+    Error *err = NULL;
+    int fds[2] = { -1, -1 };
+
+    if (socketpair(AF_UNIX, SOCK_SEQPACKET, 0, fds) < 0) {
+        error_report("tpm-emulator: Failed to create socketpair");
+        return -1;
+    }
+
+    qemu_chr_fe_set_msgfds(&tpm_pt->ctrl_dev, fds + 1, 1);
+
+    if (tpm_emulator_ctrlcmd(&tpm_pt->ctrl_dev, CMD_SET_DATAFD, &res, 0,
+                    sizeof(res)) || res != 0) {
+        error_report("tpm-emulator: Failed to send CMD_SET_DATAFD: %s",
+                     strerror(errno));
+        goto err_exit;
+    }
+
+    tpm_pt->data_ioc = QIO_CHANNEL(qio_channel_socket_new_fd(fds[0], &err));
+    if (err) {
+        error_report("tpm-emulator: Failed to create io channel : %s",
+                       error_get_pretty(err));
+        error_free(err);
+        goto err_exit;
+    }
+
+    return 0;
+
+err_exit:
+    closesocket(fds[0]);
+    closesocket(fds[1]);
+    return -1;
+}
+
+static int tpm_emulator_handle_device_opts(TPMEmulator *tpm_pt, QemuOpts *opts)
+{
+    const char *value;
+
+    value = qemu_opt_get(opts, "chardev");
+    if (value) {
+        Error *err = NULL;
+        Chardev *dev = qemu_chr_find(value);
+
+        tpm_pt->options->chardev = g_strdup(value);
+
+        if (!dev || !qemu_chr_fe_init(&tpm_pt->ctrl_dev, dev, &err)) {
+            error_report("tpm-emulator: No valid chardev found at '%s': %s",
+                         value, err ? error_get_pretty(err) : "");
+            error_free(err);
+            goto err;
+        }
+    }
+
+    if (tpm_emulator_prepare_data_fd(tpm_pt) < 0) {
+        goto err;
+    }
+
+    /* FIXME: tpm_util_test_tpmdev() accepts only on socket fd, as it also used
+     * by passthrough driver, which not yet using GIOChannel.
+     */
+    if (tpm_util_test_tpmdev(QIO_CHANNEL_SOCKET(tpm_pt->data_ioc)->fd,
+                             &tpm_pt->tpm_version)) {
+        error_report("'%s' is not emulating TPM device. Error: %s",
+                      tpm_pt->options->chardev, strerror(errno));
+        goto err;
+    }
+
+    DPRINTF("TPM Version %s", tpm_pt->tpm_version == TPM_VERSION_1_2 ? "1.2" :
+             (tpm_pt->tpm_version == TPM_VERSION_2_0 ?  "2.0" : "Unspecified"));
+
+    if (tpm_emulator_probe_caps(tpm_pt) ||
+        tpm_emulator_check_caps(tpm_pt)) {
+        goto err;
+    }
+
+    tpm_emulator_block_migration(tpm_pt);
+
+    return 0;
+
+err:
+    DPRINT("Startup error\n");
+    return -1;
+}
+
+static TPMBackend *tpm_emulator_create(QemuOpts *opts, const char *id)
+{
+    TPMBackend *tb = TPM_BACKEND(object_new(TYPE_TPM_EMULATOR));
+
+    tb->id = g_strdup(id);
+
+    if (tpm_emulator_handle_device_opts(TPM_EMULATOR(tb), opts)) {
+        goto err_exit;
+    }
+
+    return tb;
+
+err_exit:
+    object_unref(OBJECT(tb));
+
+    return NULL;
+}
+
+static TpmTypeOptions *tpm_emulator_get_tpm_options(TPMBackend *tb)
+{
+    TPMEmulator *tpm_pt = TPM_EMULATOR(tb);
+    TpmTypeOptions *options = NULL;
+    TPMEmulatorOptions *eoptions = NULL;
+
+    eoptions = g_new0(TPMEmulatorOptions, 1);
+    if (!eoptions) {
+        return NULL;
+    }
+    DPRINTF("%s", __func__);
+
+    eoptions->chardev = g_strdup(tpm_pt->options->chardev);
+    options = g_new0(TpmTypeOptions, 1);
+    if (!options) {
+        qapi_free_TPMEmulatorOptions(eoptions);
+        return NULL;
+    }
+
+    options->type = TPM_TYPE_EMULATOR;
+    options->u.emulator.data = eoptions;
+
+    return options;
+}
+
+static const QemuOptDesc tpm_emulator_cmdline_opts[] = {
+    TPM_STANDARD_CMDLINE_OPTS,
+    {
+        .name = "chardev",
+        .type = QEMU_OPT_STRING,
+        .help = "Character device to use for out-of-band control messages",
+    },
+    { /* end of list */ },
+};
+
+static const TPMDriverOps tpm_emulator_driver = {
+    .type                     = TPM_TYPE_EMULATOR,
+    .opts                     = tpm_emulator_cmdline_opts,
+    .desc                     = "TPM emulator backend driver",
+
+    .create                   = tpm_emulator_create,
+    .startup_tpm              = tpm_emulator_startup_tpm,
+    .reset                    = tpm_emulator_reset,
+    .had_startup_error        = tpm_emulator_had_startup_error,
+    .cancel_cmd               = tpm_emulator_cancel_cmd,
+    .get_tpm_established_flag = tpm_emulator_get_tpm_established_flag,
+    .reset_tpm_established_flag = tpm_emulator_reset_tpm_established_flag,
+    .get_tpm_version          = tpm_emulator_get_tpm_version,
+    .get_tpm_options          = tpm_emulator_get_tpm_options,
+};
+
+static void tpm_emulator_inst_init(Object *obj)
+{
+    TPMEmulator *tpm_pt = TPM_EMULATOR(obj);
+
+    DPRINTF("%s", __func__);
+    tpm_pt->options = g_new0(TPMEmulatorOptions, 1);
+    tpm_pt->op_executing = tpm_pt->op_canceled = false;
+    tpm_pt->had_startup_error = false;
+    tpm_pt->cur_locty_number = ~0;
+    qemu_mutex_init(&tpm_pt->state_lock);
+}
+
+static void tpm_emulator_inst_finalize(Object *obj)
+{
+    TPMEmulator *tpm_pt = TPM_EMULATOR(obj);
+
+    tpm_emulator_cancel_cmd(TPM_BACKEND(obj));
+    tpm_emulator_shutdown(tpm_pt);
+
+    if (tpm_pt->data_ioc) {
+        qio_channel_close(tpm_pt->data_ioc, NULL);
+    }
+
+    qemu_chr_fe_deinit(&tpm_pt->ctrl_dev, false);
+
+    if (tpm_pt->options) {
+        qapi_free_TPMEmulatorOptions(tpm_pt->options);
+    }
+
+    if (tpm_pt->migration_blocker) {
+        migrate_del_blocker(tpm_pt->migration_blocker);
+        error_free(tpm_pt->migration_blocker);
+    }
+}
+
+static void tpm_emulator_class_init(ObjectClass *klass, void *data)
+{
+    TPMBackendClass *tbc = TPM_BACKEND_CLASS(klass);
+    tbc->ops = &tpm_emulator_driver;
+    tbc->handle_request = tpm_emulator_handle_request;
+}
+
+static const TypeInfo tpm_emulator_info = {
+    .name = TYPE_TPM_EMULATOR,
+    .parent = TYPE_TPM_BACKEND,
+    .instance_size = sizeof(TPMEmulator),
+    .class_init = tpm_emulator_class_init,
+    .instance_init = tpm_emulator_inst_init,
+    .instance_finalize = tpm_emulator_inst_finalize,
+};
+
+static void tpm_emulator_register(void)
+{
+    type_register_static(&tpm_emulator_info);
+    tpm_register_driver(&tpm_emulator_driver);
+}
+
+type_init(tpm_emulator_register)
diff --git a/hw/tpm/tpm_ioctl.h b/hw/tpm/tpm_ioctl.h
new file mode 100644
index 0000000..33564b1
--- /dev/null
+++ b/hw/tpm/tpm_ioctl.h
@@ -0,0 +1,246 @@ 
+/*
+ * tpm_ioctl.h
+ *
+ * (c) Copyright IBM Corporation 2014, 2015.
+ *
+ * This file is licensed under the terms of the 3-clause BSD license
+ */
+#ifndef _TPM_IOCTL_H_
+#define _TPM_IOCTL_H_
+
+#include <stdint.h>
+#include <sys/uio.h>
+#include <sys/types.h>
+#include <sys/ioctl.h>
+
+/*
+ * Every response from a command involving a TPM command execution must hold
+ * the ptm_res as the first element.
+ * ptm_res corresponds to the error code of a command executed by the TPM.
+ */
+
+typedef uint32_t ptm_res;
+
+/* PTM_GET_TPMESTABLISHED: get the establishment bit */
+struct ptm_est {
+    union {
+        struct {
+            ptm_res tpm_result;
+            unsigned char bit; /* TPM established bit */
+        } resp; /* response */
+    } u;
+};
+
+/* PTM_RESET_TPMESTABLISHED: reset establishment bit */
+struct ptm_reset_est {
+    union {
+        struct {
+            uint8_t loc; /* locality to use */
+        } req; /* request */
+        struct {
+            ptm_res tpm_result;
+        } resp; /* response */
+    } u;
+};
+
+/* PTM_INIT */
+struct ptm_init {
+    union {
+        struct {
+            uint32_t init_flags; /* see definitions below */
+        } req; /* request */
+        struct {
+            ptm_res tpm_result;
+        } resp; /* response */
+    } u;
+};
+
+/* above init_flags */
+#define PTM_INIT_FLAG_DELETE_VOLATILE (1 << 0)
+    /* delete volatile state file after reading it */
+
+/* PTM_SET_LOCALITY */
+struct ptm_loc {
+    union {
+        struct {
+            uint8_t loc; /* locality to set */
+        } req; /* request */
+        struct {
+            ptm_res tpm_result;
+        } resp; /* response */
+    } u;
+};
+
+/* PTM_HASH_DATA: hash given data */
+struct ptm_hdata {
+    union {
+        struct {
+            uint32_t length;
+            uint8_t data[4096];
+        } req; /* request */
+        struct {
+            ptm_res tpm_result;
+        } resp; /* response */
+    } u;
+};
+
+/*
+ * size of the TPM state blob to transfer; x86_64 can handle 8k,
+ * ppc64le only ~7k; keep the response below a 4k page size
+ */
+#define PTM_STATE_BLOB_SIZE (3 * 1024)
+
+/*
+ * The following is the data structure to get state blobs from the TPM.
+ * If the size of the state blob exceeds the PTM_STATE_BLOB_SIZE, multiple reads
+ * with this ioctl and with adjusted offset are necessary. All bytes
+ * must be transferred and the transfer is done once the last byte has been
+ * returned.
+ * It is possible to use the read() interface for reading the data; however, the
+ * first bytes of the state blob will be part of the response to the ioctl(); a
+ * subsequent read() is only necessary if the total length (totlength) exceeds
+ * the number of received bytes. seek() is not supported.
+ */
+struct ptm_getstate {
+    union {
+        struct {
+            uint32_t state_flags; /* may be: PTM_STATE_FLAG_DECRYPTED */
+            uint32_t type;        /* which blob to pull */
+            uint32_t offset;      /* offset from where to read */
+        } req; /* request */
+        struct {
+            ptm_res tpm_result;
+            uint32_t state_flags; /* may be: PTM_STATE_FLAG_ENCRYPTED */
+            uint32_t totlength;   /* total length that will be transferred */
+            uint32_t length;      /* number of bytes in following buffer */
+            uint8_t  data[PTM_STATE_BLOB_SIZE];
+        } resp; /* response */
+    } u;
+};
+
+/* TPM state blob types */
+#define PTM_BLOB_TYPE_PERMANENT  1
+#define PTM_BLOB_TYPE_VOLATILE   2
+#define PTM_BLOB_TYPE_SAVESTATE  3
+
+/* state_flags above : */
+#define PTM_STATE_FLAG_DECRYPTED     1 /* on input:  get decrypted state */
+#define PTM_STATE_FLAG_ENCRYPTED     2 /* on output: state is encrypted */
+
+/*
+ * The following is the data structure to set state blobs in the TPM.
+ * If the size of the state blob exceeds the PTM_STATE_BLOB_SIZE, multiple
+ * 'writes' using this ioctl are necessary. The last packet is indicated
+ * by the length being smaller than the PTM_STATE_BLOB_SIZE.
+ * The very first packet may have a length indicator of '0' enabling
+ * a write() with all the bytes from a buffer. If the write() interface
+ * is used, a final ioctl with a non-full buffer must be made to indicate
+ * that all data were transferred (a write with 0 bytes would not work).
+ */
+struct ptm_setstate {
+    union {
+        struct {
+            uint32_t state_flags; /* may be PTM_STATE_FLAG_ENCRYPTED */
+            uint32_t type;        /* which blob to set */
+            uint32_t length;      /* length of the data;
+                                     use 0 on the first packet to
+                                     transfer using write() */
+            uint8_t data[PTM_STATE_BLOB_SIZE];
+        } req; /* request */
+        struct {
+            ptm_res tpm_result;
+        } resp; /* response */
+    } u;
+};
+
+/*
+ * PTM_GET_CONFIG: Data structure to get runtime configuration information
+ * such as which keys are applied.
+ */
+struct ptm_getconfig {
+    union {
+        struct {
+            ptm_res tpm_result;
+            uint32_t flags;
+        } resp; /* response */
+    } u;
+};
+
+#define PTM_CONFIG_FLAG_FILE_KEY        0x1
+#define PTM_CONFIG_FLAG_MIGRATION_KEY   0x2
+
+
+typedef uint64_t ptm_cap;
+typedef struct ptm_est ptm_est;
+typedef struct ptm_reset_est ptm_reset_est;
+typedef struct ptm_loc ptm_loc;
+typedef struct ptm_hdata ptm_hdata;
+typedef struct ptm_init ptm_init;
+typedef struct ptm_getstate ptm_getstate;
+typedef struct ptm_setstate ptm_setstate;
+typedef struct ptm_getconfig ptm_getconfig;
+
+/* capability flags returned by PTM_GET_CAPABILITY */
+#define PTM_CAP_INIT               (1)
+#define PTM_CAP_SHUTDOWN           (1 << 1)
+#define PTM_CAP_GET_TPMESTABLISHED (1 << 2)
+#define PTM_CAP_SET_LOCALITY       (1 << 3)
+#define PTM_CAP_HASHING            (1 << 4)
+#define PTM_CAP_CANCEL_TPM_CMD     (1 << 5)
+#define PTM_CAP_STORE_VOLATILE     (1 << 6)
+#define PTM_CAP_RESET_TPMESTABLISHED (1 << 7)
+#define PTM_CAP_GET_STATEBLOB      (1 << 8)
+#define PTM_CAP_SET_STATEBLOB      (1 << 9)
+#define PTM_CAP_STOP               (1 << 10)
+#define PTM_CAP_GET_CONFIG         (1 << 11)
+#define PTM_CAP_SET_DATAFD         (1 << 12)
+
+enum {
+    PTM_GET_CAPABILITY     = _IOR('P', 0, ptm_cap),
+    PTM_INIT               = _IOWR('P', 1, ptm_init),
+    PTM_SHUTDOWN           = _IOR('P', 2, ptm_res),
+    PTM_GET_TPMESTABLISHED = _IOR('P', 3, ptm_est),
+    PTM_SET_LOCALITY       = _IOWR('P', 4, ptm_loc),
+    PTM_HASH_START         = _IOR('P', 5, ptm_res),
+    PTM_HASH_DATA          = _IOWR('P', 6, ptm_hdata),
+    PTM_HASH_END           = _IOR('P', 7, ptm_res),
+    PTM_CANCEL_TPM_CMD     = _IOR('P', 8, ptm_res),
+    PTM_STORE_VOLATILE     = _IOR('P', 9, ptm_res),
+    PTM_RESET_TPMESTABLISHED = _IOWR('P', 10, ptm_reset_est),
+    PTM_GET_STATEBLOB      = _IOWR('P', 11, ptm_getstate),
+    PTM_SET_STATEBLOB      = _IOWR('P', 12, ptm_setstate),
+    PTM_STOP               = _IOR('P', 13, ptm_res),
+    PTM_GET_CONFIG         = _IOR('P', 14, ptm_getconfig),
+    PTM_SET_DATAFD         = _IOR('P', 15, ptm_res),
+};
+
+/*
+ * Commands used by the non-CUSE TPMs
+ *
+ * All messages container big-endian data.
+ *
+ * The return messages only contain the 'resp' part of the unions
+ * in the data structures above. Besides that the limits in the
+ * buffers above (ptm_hdata:u.req.data and ptm_get_state:u.resp.data
+ * and ptm_set_state:u.req.data) are 0xffffffff.
+ */
+enum {
+    CMD_GET_CAPABILITY = 1,
+    CMD_INIT,
+    CMD_SHUTDOWN,
+    CMD_GET_TPMESTABLISHED,
+    CMD_SET_LOCALITY,
+    CMD_HASH_START,
+    CMD_HASH_DATA,
+    CMD_HASH_END,
+    CMD_CANCEL_TPM_CMD,
+    CMD_STORE_VOLATILE,
+    CMD_RESET_TPMESTABLISHED,
+    CMD_GET_STATEBLOB,
+    CMD_SET_STATEBLOB,
+    CMD_STOP,
+    CMD_GET_CONFIG,
+    CMD_SET_DATAFD
+};
+
+#endif /* _TPM_IOCTL_H */
diff --git a/qapi/tpm.json b/qapi/tpm.json
index e8b2d8d..7093f26 100644
--- a/qapi/tpm.json
+++ b/qapi/tpm.json
@@ -39,10 +39,12 @@ 
 # An enumeration of TPM types
 #
 # @passthrough: TPM passthrough type
+# @emulator: Software Emulator TPM type
+#            Since: 2.11
 #
 # Since: 1.5
 ##
-{ 'enum': 'TpmType', 'data': [ 'passthrough' ] }
+{ 'enum': 'TpmType', 'data': [ 'passthrough', 'emulator' ] }
 
 ##
 # @query-tpm-types:
@@ -56,7 +58,7 @@ 
 # Example:
 #
 # -> { "execute": "query-tpm-types" }
-# <- { "return": [ "passthrough" ] }
+# <- { "return": [ "passthrough", "emulator" ] }
 #
 ##
 { 'command': 'query-tpm-types', 'returns': ['TpmType'] }
@@ -77,16 +79,29 @@ 
                                              '*cancel-path' : 'str'} }
 
 ##
+# @TPMEmulatorOptions:
+#
+# Information about the TPM emulator type
+#
+# @chardev: Name of a unix socket chardev
+#
+# Since: 2.11
+##
+{ 'struct': 'TPMEmulatorOptions', 'data': { 'chardev' : 'str' } }
+
+##
 # @TpmTypeOptions:
 #
 # A union referencing different TPM backend types' configuration options
 #
 # @type: 'passthrough' The configuration options for the TPM passthrough type
+#        'emulator' The configuration options for TPM emulator backend type
 #
 # Since: 1.5
 ##
 { 'union': 'TpmTypeOptions',
-   'data': { 'passthrough' : 'TPMPassthroughOptions' } }
+   'data': { 'passthrough' : 'TPMPassthroughOptions',
+             'emulator': 'TPMEmulatorOptions' } }
 
 ##
 # @TPMInfo:
diff --git a/qemu-options.hx b/qemu-options.hx
index 77859a2..1e93e53 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -3121,7 +3121,9 @@  DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \
     "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n"
     "                use path to provide path to a character device; default is /dev/tpm0\n"
     "                use cancel-path to provide path to TPM's cancel sysfs entry; if\n"
-    "                not provided it will be searched for in /sys/class/misc/tpm?/device\n",
+    "                not provided it will be searched for in /sys/class/misc/tpm?/device\n"
+    "-tpmdev emulator,id=id,chardev=dev\n"
+    "                configure the TPM device using chardev backend\n",
     QEMU_ARCH_ALL)
 STEXI
 
@@ -3130,8 +3132,8 @@  The general form of a TPM device option is:
 
 @item -tpmdev @var{backend} ,id=@var{id} [,@var{options}]
 @findex -tpmdev
-Backend type must be:
-@option{passthrough}.
+Backend type must be either one of the following:
+@option{passthrough}, @option{emulator}.
 
 The specific backend type will determine the applicable options.
 The @code{-tpmdev} option creates the TPM backend and requires a
@@ -3181,6 +3183,20 @@  To create a passthrough TPM use the following two options:
 Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by
 @code{tpmdev=tpm0} in the device option.
 
+@item -tpmdev emulator, id=@var{id}, chardev=@var{dev}
+
+(Linux-host only) Enable access to a TPM emulator using Unix domain socket based
+chardev backend.
+
+@option{chardev} specifies the unique ID of a character device backend that provides connection to the software TPM server.
+
+To create a TPM emulator backend device with chardev socket backend:
+@example
+
+-chardev socket,id=chrtpm,path=/tmp/swtpm-ctrl -tpmdev emulator,id=tpm0,chardev=chrtpm -device tpm-tis,tpmdev=tpm0
+
+@end example
+
 @end table
 
 ETEXI