From patchwork Thu Jun 28 13:22:11 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Richard W.M. Jones" X-Patchwork-Id: 10493941 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 891506022E for ; Thu, 28 Jun 2018 13:25:48 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 705382A110 for ; Thu, 28 Jun 2018 13:25:48 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 646972A131; Thu, 28 Jun 2018 13:25:48 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 958262A110 for ; Thu, 28 Jun 2018 13:25:46 +0000 (UTC) Received: from localhost ([::1]:36703 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fYWvh-00057e-OW for patchwork-qemu-devel@patchwork.kernel.org; Thu, 28 Jun 2018 09:25:45 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:54194) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fYWsd-0002oq-FK for qemu-devel@nongnu.org; Thu, 28 Jun 2018 09:22:38 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fYWsZ-0001dS-MF for qemu-devel@nongnu.org; Thu, 28 Jun 2018 09:22:35 -0400 Received: from mx1.redhat.com ([209.132.183.28]:55700) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fYWsR-00014n-SK; Thu, 28 Jun 2018 09:22:24 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id AAD53356E7; Thu, 28 Jun 2018 13:22:17 +0000 (UTC) Received: from moo.home.annexia.org (ovpn-117-157.ams2.redhat.com [10.36.117.157]) by smtp.corp.redhat.com (Postfix) with ESMTP id 14DE08CCD5; Thu, 28 Jun 2018 13:22:15 +0000 (UTC) From: "Richard W.M. Jones" To: qemu-devel@nongnu.org Date: Thu, 28 Jun 2018 14:22:11 +0100 Message-Id: <20180628132211.8795-2-rjones@redhat.com> In-Reply-To: <20180628132211.8795-1-rjones@redhat.com> References: <20180628132211.8795-1-rjones@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.30]); Thu, 28 Jun 2018 13:22:17 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH v3] crypto: Implement TLS Pre-Shared Keys (PSK). X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: qemu-block@nongnu.org Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP Pre-Shared Keys (PSK) is a simpler mechanism for enabling TLS connections than using certificates. It requires only a simple secret key: $ mkdir -m 0700 /tmp/keys $ psktool -u rjones -p /tmp/keys/keys.psk $ cat /tmp/keys/keys.psk rjones:d543770c15ad93d76443fb56f501a31969235f47e999720ae8d2336f6a13fcbc The key can be secretly shared between clients and servers. Clients must specify the directory containing the "keys.psk" file and a username (defaults to "qemu"). Servers must specify only the directory. Example NBD client: $ qemu-img info \ --object tls-creds-psk,id=tls0,dir=/tmp/keys,username=rjones,endpoint=client \ --image-opts \ file.driver=nbd,file.host=localhost,file.port=10809,file.tls-creds=tls0,file.export=/ Example NBD server using qemu-nbd: $ qemu-nbd -t -x / \ --object tls-creds-psk,id=tls0,endpoint=server,dir=/tmp/keys \ --tls-creds tls0 \ image.qcow2 Example NBD server using nbdkit: $ nbdkit -n -e / -fv \ --tls=on --tls-psk=/tmp/keys/keys.psk \ file file=disk.img Signed-off-by: Richard W.M. Jones Acked-by: Eric Blake --- crypto/Makefile.objs | 1 + crypto/tlscredspsk.c | 300 +++++++++++++++++++++++++++++++++ crypto/tlssession.c | 50 +++++- crypto/trace-events | 3 + include/crypto/tlscredspsk.h | 106 ++++++++++++ qemu-doc.texi | 37 ++++ qemu-options.hx | 24 +++ tests/Makefile.include | 4 +- tests/crypto-tls-psk-helpers.c | 50 ++++++ tests/crypto-tls-psk-helpers.h | 29 ++++ tests/test-crypto-tlssession.c | 185 +++++++++++++++++--- 11 files changed, 763 insertions(+), 26 deletions(-) diff --git a/crypto/Makefile.objs b/crypto/Makefile.objs index 2b99e08062..756bab111b 100644 --- a/crypto/Makefile.objs +++ b/crypto/Makefile.objs @@ -15,6 +15,7 @@ crypto-obj-$(CONFIG_AF_ALG) += cipher-afalg.o crypto-obj-$(CONFIG_AF_ALG) += hash-afalg.o crypto-obj-y += tlscreds.o crypto-obj-y += tlscredsanon.o +crypto-obj-y += tlscredspsk.o crypto-obj-y += tlscredsx509.o crypto-obj-y += tlssession.o crypto-obj-y += secret.o diff --git a/crypto/tlscredspsk.c b/crypto/tlscredspsk.c new file mode 100644 index 0000000000..e9ec23b457 --- /dev/null +++ b/crypto/tlscredspsk.c @@ -0,0 +1,300 @@ +/* + * QEMU crypto TLS Pre-Shared Keys (PSK) support + * + * Copyright (c) 2018 Red Hat, Inc. + * + * 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 . + * + */ + +#include "qemu/osdep.h" +#include "crypto/tlscredspsk.h" +#include "tlscredspriv.h" +#include "qapi/error.h" +#include "qom/object_interfaces.h" +#include "trace.h" + + +#ifdef CONFIG_GNUTLS + +static int +lookup_key(const char *pskfile, const char *username, gnutls_datum_t *key, + Error **errp) +{ + FILE *fp; + char line[1024]; /* Maximum key length in psktool is 512 bytes. */ + size_t ulen = strlen(username); + size_t len; + + fp = fopen(pskfile, "r"); + if (fp == NULL) { + error_setg_errno(errp, errno, "Cannot open PSK file %s", pskfile); + return -1; + } + while (fgets(line, sizeof line, fp) != NULL) { + if (strncmp(line, username, ulen) == 0 && line[ulen] == ':') { + len = strlen(line); + if (len > 0 && line[len - 1] == '\n') { + len--; + line[len] = '\0'; + } + key->data = (unsigned char *) g_strdup(&line[ulen + 1]); + key->size = len - ulen - 1; + fclose(fp); + return 0; + } + } + fclose(fp); + error_setg(errp, "Username %s not found in PSK file %s", + username, pskfile); + return -1; +} + +static int +qcrypto_tls_creds_psk_load(QCryptoTLSCredsPSK *creds, + Error **errp) +{ + char *pskfile = NULL, *dhparams = NULL; + const char *username; + int ret; + int rv = -1; + gnutls_datum_t key = { .data = NULL }; + + trace_qcrypto_tls_creds_psk_load(creds, + creds->parent_obj.dir ? creds->parent_obj.dir : ""); + + if (creds->parent_obj.endpoint == QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) { + if (qcrypto_tls_creds_get_path(&creds->parent_obj, + QCRYPTO_TLS_CREDS_DH_PARAMS, + false, &dhparams, errp) < 0 || + qcrypto_tls_creds_get_path(&creds->parent_obj, + QCRYPTO_TLS_CREDS_PSKFILE, + true, &pskfile, errp) < 0) { + goto cleanup; + } + + ret = gnutls_psk_allocate_server_credentials(&creds->data.server); + if (ret < 0) { + error_setg(errp, "Cannot allocate credentials: %s", + gnutls_strerror(ret)); + goto cleanup; + } + + if (qcrypto_tls_creds_get_dh_params_file(&creds->parent_obj, dhparams, + &creds->parent_obj.dh_params, + errp) < 0) { + goto cleanup; + } + + gnutls_psk_set_server_credentials_file(creds->data.server, pskfile); + gnutls_psk_set_server_dh_params(creds->data.server, + creds->parent_obj.dh_params); + } else { + if (qcrypto_tls_creds_get_path(&creds->parent_obj, + QCRYPTO_TLS_CREDS_PSKFILE, + true, &pskfile, errp) < 0) { + goto cleanup; + } + + if (creds->username) { + username = creds->username; + } else { + username = "qemu"; + } + if (lookup_key(pskfile, username, &key, errp) != 0) { + goto cleanup; + } + + ret = gnutls_psk_allocate_client_credentials(&creds->data.client); + if (ret < 0) { + error_setg(errp, "Cannot allocate credentials: %s", + gnutls_strerror(ret)); + goto cleanup; + } + + gnutls_psk_set_client_credentials(creds->data.client, + username, &key, GNUTLS_PSK_KEY_HEX); + } + + rv = 0; + cleanup: + g_free(key.data); + g_free(pskfile); + g_free(dhparams); + return rv; +} + + +static void +qcrypto_tls_creds_psk_unload(QCryptoTLSCredsPSK *creds) +{ + if (creds->parent_obj.endpoint == QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT) { + if (creds->data.client) { + gnutls_psk_free_client_credentials(creds->data.client); + creds->data.client = NULL; + } + } else { + if (creds->data.server) { + gnutls_psk_free_server_credentials(creds->data.server); + creds->data.server = NULL; + } + } + if (creds->parent_obj.dh_params) { + gnutls_dh_params_deinit(creds->parent_obj.dh_params); + creds->parent_obj.dh_params = NULL; + } +} + +#else /* ! CONFIG_GNUTLS */ + + +static void +qcrypto_tls_creds_psk_load(QCryptoTLSCredsPSK *creds G_GNUC_UNUSED, + Error **errp) +{ + error_setg(errp, "TLS credentials support requires GNUTLS"); +} + + +static void +qcrypto_tls_creds_psk_unload(QCryptoTLSCredsPSK *creds G_GNUC_UNUSED) +{ + /* nada */ +} + + +#endif /* ! CONFIG_GNUTLS */ + + +static void +qcrypto_tls_creds_psk_prop_set_loaded(Object *obj, + bool value, + Error **errp) +{ + QCryptoTLSCredsPSK *creds = QCRYPTO_TLS_CREDS_PSK(obj); + + if (value) { + qcrypto_tls_creds_psk_load(creds, errp); + } else { + qcrypto_tls_creds_psk_unload(creds); + } +} + + +#ifdef CONFIG_GNUTLS + + +static bool +qcrypto_tls_creds_psk_prop_get_loaded(Object *obj, + Error **errp G_GNUC_UNUSED) +{ + QCryptoTLSCredsPSK *creds = QCRYPTO_TLS_CREDS_PSK(obj); + + if (creds->parent_obj.endpoint == QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) { + return creds->data.server != NULL; + } else { + return creds->data.client != NULL; + } +} + + +#else /* ! CONFIG_GNUTLS */ + + +static bool +qcrypto_tls_creds_psk_prop_get_loaded(Object *obj G_GNUC_UNUSED, + Error **errp G_GNUC_UNUSED) +{ + return false; +} + + +#endif /* ! CONFIG_GNUTLS */ + + +static void +qcrypto_tls_creds_psk_complete(UserCreatable *uc, Error **errp) +{ + object_property_set_bool(OBJECT(uc), true, "loaded", errp); +} + + +static void +qcrypto_tls_creds_psk_finalize(Object *obj) +{ + QCryptoTLSCredsPSK *creds = QCRYPTO_TLS_CREDS_PSK(obj); + + qcrypto_tls_creds_psk_unload(creds); +} + +static void +qcrypto_tls_creds_psk_prop_set_username(Object *obj, + const char *value, + Error **errp G_GNUC_UNUSED) +{ + QCryptoTLSCredsPSK *creds = QCRYPTO_TLS_CREDS_PSK(obj); + + creds->username = g_strdup(value); +} + + +static char * +qcrypto_tls_creds_psk_prop_get_username(Object *obj, + Error **errp G_GNUC_UNUSED) +{ + QCryptoTLSCredsPSK *creds = QCRYPTO_TLS_CREDS_PSK(obj); + + return g_strdup(creds->username); +} + +static void +qcrypto_tls_creds_psk_class_init(ObjectClass *oc, void *data) +{ + UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc); + + ucc->complete = qcrypto_tls_creds_psk_complete; + + object_class_property_add_bool(oc, "loaded", + qcrypto_tls_creds_psk_prop_get_loaded, + qcrypto_tls_creds_psk_prop_set_loaded, + NULL); + object_class_property_add_str(oc, "username", + qcrypto_tls_creds_psk_prop_get_username, + qcrypto_tls_creds_psk_prop_set_username, + NULL); +} + + +static const TypeInfo qcrypto_tls_creds_psk_info = { + .parent = TYPE_QCRYPTO_TLS_CREDS, + .name = TYPE_QCRYPTO_TLS_CREDS_PSK, + .instance_size = sizeof(QCryptoTLSCredsPSK), + .instance_finalize = qcrypto_tls_creds_psk_finalize, + .class_size = sizeof(QCryptoTLSCredsPSKClass), + .class_init = qcrypto_tls_creds_psk_class_init, + .interfaces = (InterfaceInfo[]) { + { TYPE_USER_CREATABLE }, + { } + } +}; + + +static void +qcrypto_tls_creds_psk_register_types(void) +{ + type_register_static(&qcrypto_tls_creds_psk_info); +} + + +type_init(qcrypto_tls_creds_psk_register_types); diff --git a/crypto/tlssession.c b/crypto/tlssession.c index 96a02deb69..50df64e0a9 100644 --- a/crypto/tlssession.c +++ b/crypto/tlssession.c @@ -21,6 +21,7 @@ #include "qemu/osdep.h" #include "crypto/tlssession.h" #include "crypto/tlscredsanon.h" +#include "crypto/tlscredspsk.h" #include "crypto/tlscredsx509.h" #include "qapi/error.h" #include "qemu/acl.h" @@ -88,6 +89,8 @@ qcrypto_tls_session_pull(void *opaque, void *buf, size_t len) return session->readFunc(buf, len, session->opaque); } +#define TLS_PRIORITY_ADDITIONAL_ANON "+ANON-DH" +#define TLS_PRIORITY_ADDITIONAL_PSK "+ECDHE-PSK:+DHE-PSK:+PSK" QCryptoTLSSession * qcrypto_tls_session_new(QCryptoTLSCreds *creds, @@ -135,9 +138,12 @@ qcrypto_tls_session_new(QCryptoTLSCreds *creds, char *prio; if (creds->priority != NULL) { - prio = g_strdup_printf("%s:+ANON-DH", creds->priority); + prio = g_strdup_printf("%s:%s", + creds->priority, + TLS_PRIORITY_ADDITIONAL_ANON); } else { - prio = g_strdup(CONFIG_TLS_PRIORITY ":+ANON-DH"); + prio = g_strdup(CONFIG_TLS_PRIORITY ":" + TLS_PRIORITY_ADDITIONAL_ANON); } ret = gnutls_priority_set_direct(session->handle, prio, NULL); @@ -162,6 +168,42 @@ qcrypto_tls_session_new(QCryptoTLSCreds *creds, gnutls_strerror(ret)); goto error; } + } else if (object_dynamic_cast(OBJECT(creds), + TYPE_QCRYPTO_TLS_CREDS_PSK)) { + QCryptoTLSCredsPSK *pcreds = QCRYPTO_TLS_CREDS_PSK(creds); + char *prio; + + if (creds->priority != NULL) { + prio = g_strdup_printf("%s:%s", + creds->priority, + TLS_PRIORITY_ADDITIONAL_PSK); + } else { + prio = g_strdup(CONFIG_TLS_PRIORITY ":" + TLS_PRIORITY_ADDITIONAL_PSK); + } + + ret = gnutls_priority_set_direct(session->handle, prio, NULL); + if (ret < 0) { + error_setg(errp, "Unable to set TLS session priority %s: %s", + prio, gnutls_strerror(ret)); + g_free(prio); + goto error; + } + g_free(prio); + if (creds->endpoint == QCRYPTO_TLS_CREDS_ENDPOINT_SERVER) { + ret = gnutls_credentials_set(session->handle, + GNUTLS_CRD_PSK, + pcreds->data.server); + } else { + ret = gnutls_credentials_set(session->handle, + GNUTLS_CRD_PSK, + pcreds->data.client); + } + if (ret < 0) { + error_setg(errp, "Cannot set session credentials: %s", + gnutls_strerror(ret)); + goto error; + } } else if (object_dynamic_cast(OBJECT(creds), TYPE_QCRYPTO_TLS_CREDS_X509)) { QCryptoTLSCredsX509 *tcreds = QCRYPTO_TLS_CREDS_X509(creds); @@ -353,6 +395,10 @@ qcrypto_tls_session_check_credentials(QCryptoTLSSession *session, TYPE_QCRYPTO_TLS_CREDS_ANON)) { trace_qcrypto_tls_session_check_creds(session, "nop"); return 0; + } else if (object_dynamic_cast(OBJECT(session->creds), + TYPE_QCRYPTO_TLS_CREDS_PSK)) { + trace_qcrypto_tls_session_check_creds(session, "nop"); + return 0; } else if (object_dynamic_cast(OBJECT(session->creds), TYPE_QCRYPTO_TLS_CREDS_X509)) { if (session->creds->verifyPeer) { diff --git a/crypto/trace-events b/crypto/trace-events index e589990359..597389b73c 100644 --- a/crypto/trace-events +++ b/crypto/trace-events @@ -7,6 +7,9 @@ qcrypto_tls_creds_get_path(void *creds, const char *filename, const char *path) # crypto/tlscredsanon.c qcrypto_tls_creds_anon_load(void *creds, const char *dir) "TLS creds anon load creds=%p dir=%s" +# crypto/tlscredspsk.c +qcrypto_tls_creds_psk_load(void *creds, const char *dir) "TLS creds psk load creds=%p dir=%s" + # crypto/tlscredsx509.c qcrypto_tls_creds_x509_load(void *creds, const char *dir) "TLS creds x509 load creds=%p dir=%s" qcrypto_tls_creds_x509_check_basic_constraints(void *creds, const char *file, int status) "TLS creds x509 check basic constraints creds=%p file=%s status=%d" diff --git a/include/crypto/tlscredspsk.h b/include/crypto/tlscredspsk.h new file mode 100644 index 0000000000..6bc2158ea9 --- /dev/null +++ b/include/crypto/tlscredspsk.h @@ -0,0 +1,106 @@ +/* + * QEMU crypto TLS Pre-Shared Key (PSK) support + * + * Copyright (c) 2018 Red Hat, Inc. + * + * 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 . + * + */ + +#ifndef QCRYPTO_TLSCREDSPSK_H +#define QCRYPTO_TLSCREDSPSK_H + +#include "crypto/tlscreds.h" + +#define TYPE_QCRYPTO_TLS_CREDS_PSK "tls-creds-psk" +#define QCRYPTO_TLS_CREDS_PSK(obj) \ + OBJECT_CHECK(QCryptoTLSCredsPSK, (obj), TYPE_QCRYPTO_TLS_CREDS_PSK) + +typedef struct QCryptoTLSCredsPSK QCryptoTLSCredsPSK; +typedef struct QCryptoTLSCredsPSKClass QCryptoTLSCredsPSKClass; + +#define QCRYPTO_TLS_CREDS_PSKFILE "keys.psk" + +/** + * QCryptoTLSCredsPSK: + * + * The QCryptoTLSCredsPSK object provides a representation + * of the Pre-Shared Key credential used to perform a TLS handshake. + * + * This is a user creatable object, which can be instantiated + * via object_new_propv(): + * + * + * Creating TLS-PSK credential objects in code + * + * Object *obj; + * Error *err = NULL; + * obj = object_new_propv(TYPE_QCRYPTO_TLS_CREDS_PSK, + * "tlscreds0", + * &err, + * "dir", "/path/to/dir", + * "endpoint", "client", + * NULL); + * + * + * + * Or via QMP: + * + * + * Creating TLS-PSK credential objects via QMP + * + * { + * "execute": "object-add", "arguments": { + * "id": "tlscreds0", + * "qom-type": "tls-creds-psk", + * "props": { + * "dir": "/path/to/dir", + * "endpoint": "client", + * } + * } + * } + * + * + * + * Or via the CLI: + * + * + * Creating TLS-PSK credential objects via CLI + * + * qemu-system-x86_64 -object tls-creds-psk,id=tlscreds0,\ + * endpoint=client,dir=/path/to/dir[,username=qemu] + * + * + * + * The PSK file can be created and managed using psktool. + */ + +struct QCryptoTLSCredsPSK { + QCryptoTLSCreds parent_obj; + char *username; +#ifdef CONFIG_GNUTLS + union { + gnutls_psk_server_credentials_t server; + gnutls_psk_client_credentials_t client; + } data; +#endif +}; + + +struct QCryptoTLSCredsPSKClass { + QCryptoTLSCredsClass parent_class; +}; + + +#endif /* QCRYPTO_TLSCREDSPSK_H */ diff --git a/qemu-doc.texi b/qemu-doc.texi index 282bc3dc35..a4f9373699 100644 --- a/qemu-doc.texi +++ b/qemu-doc.texi @@ -1262,6 +1262,7 @@ The recommendation is for the server to keep its certificates in either * tls_generate_server:: * tls_generate_client:: * tls_creds_setup:: +* tls_psk:: @end menu @node tls_generate_ca @subsection Setup the Certificate Authority @@ -1510,6 +1511,42 @@ example with VNC: $QEMU -vnc 0.0.0.0:0,tls-creds=tls0 @end example +@node tls_psk +@subsection TLS Pre-Shared Keys (PSK) + +Instead of using certificates, you may also use TLS Pre-Shared Keys +(TLS-PSK). This can be simpler to set up than certificates but is +less scalable. + +Use the GnuTLS @code{psktool} program to generate a @code{keys.psk} +file containing one or more usernames and random keys: + +@example +mkdir -m 0700 /tmp/keys +psktool -u rich -p /tmp/keys/keys.psk +@end example + +TLS-enabled servers such as qemu-nbd can use this directory like so: + +@example +qemu-nbd \ + -t -x / \ + --object tls-creds-psk,id=tls0,endpoint=server,dir=/tmp/keys \ + --tls-creds tls0 \ + image.qcow2 +@end example + +When connecting from a qemu-based client you must specify the +directory containing @code{keys.psk} and an optional @var{username} +(defaults to ``qemu''): + +@example +qemu-img info \ + --object tls-creds-psk,id=tls0,dir=/tmp/keys,username=rich,endpoint=client \ + --image-opts \ + file.driver=nbd,file.host=localhost,file.port=10809,file.tls-creds=tls0,file.export=/ +@end example + @node gdb_usage @section GDB usage diff --git a/qemu-options.hx b/qemu-options.hx index d5b0c26e8e..afc5e6528f 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -4099,6 +4099,30 @@ expensive operation that consumes random pool entropy, so it is recommended that a persistent set of parameters be generated upfront and saved. +@item -object tls-creds-psk,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/keys/dir}[,username=@var{username}] + +Creates a TLS Pre-Shared Keys (PSK) credentials object, which can be used to provide +TLS support on network backends. The @option{id} parameter is a unique +ID which network backends will use to access the credentials. The +@option{endpoint} is either @option{server} or @option{client} depending +on whether the QEMU network backend that uses the credentials will be +acting as a client or as a server. For clients only, @option{username} +is the username which will be sent to the server. If omitted +it defaults to ``qemu''. + +The @var{dir} parameter tells QEMU where to find the keys file. +It is called ``@var{dir}/keys.psk'' and contains ``username:key'' +pairs. This file can most easily be created using the GnuTLS +@code{psktool} program. + +For server endpoints, @var{dir} may also contain a file +@var{dh-params.pem} providing diffie-hellman parameters to use +for the TLS server. If the file is missing, QEMU will generate +a set of DH parameters at startup. This is a computationally +expensive operation that consumes random pool entropy, so it is +recommended that a persistent set of parameters be generated +upfront and saved. + @item -object tls-creds-x509,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/cred/dir},priority=@var{priority},verify-peer=@var{on|off},passwordid=@var{id} Creates a TLS anonymous credentials object, which can be used to provide diff --git a/tests/Makefile.include b/tests/Makefile.include index e8bb2d8f66..8859e88ffb 100644 --- a/tests/Makefile.include +++ b/tests/Makefile.include @@ -723,7 +723,9 @@ tests/test-crypto-tlscredsx509$(EXESUF): tests/test-crypto-tlscredsx509.o \ tests/test-crypto-tlssession.o-cflags := $(TASN1_CFLAGS) tests/test-crypto-tlssession$(EXESUF): tests/test-crypto-tlssession.o \ - tests/crypto-tls-x509-helpers.o tests/pkix_asn1_tab.o $(test-crypto-obj-y) + tests/crypto-tls-x509-helpers.o tests/pkix_asn1_tab.o \ + tests/crypto-tls-psk-helpers.o \ + $(test-crypto-obj-y) tests/test-util-sockets$(EXESUF): tests/test-util-sockets.o \ tests/socket-helpers.o $(test-util-obj-y) tests/test-io-task$(EXESUF): tests/test-io-task.o $(test-io-obj-y) diff --git a/tests/crypto-tls-psk-helpers.c b/tests/crypto-tls-psk-helpers.c new file mode 100644 index 0000000000..a8395477c3 --- /dev/null +++ b/tests/crypto-tls-psk-helpers.c @@ -0,0 +1,50 @@ +/* + * Copyright (C) 2015-2018 Red Hat, Inc. + * + * 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 2.1 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 + * . + * + * Author: Richard W.M. Jones + */ + +#include "qemu/osdep.h" + +/* Include this first because it defines QCRYPTO_HAVE_TLS_TEST_SUPPORT */ +#include "crypto-tls-x509-helpers.h" + +#include "crypto-tls-psk-helpers.h" +#include "qemu/sockets.h" + +#ifdef QCRYPTO_HAVE_TLS_TEST_SUPPORT + +void test_tls_psk_init(const char *pskfile) +{ + FILE *fp; + + fp = fopen(pskfile, "w"); + if (fp == NULL) { + g_critical("Failed to create pskfile %s", pskfile); + abort(); + } + /* Don't do this in real applications! Use psktool. */ + fprintf(fp, "qemu:009d5638c40fde0c\n"); + fclose(fp); +} + +void test_tls_psk_cleanup(const char *pskfile) +{ + unlink(pskfile); +} + +#endif /* QCRYPTO_HAVE_TLS_TEST_SUPPORT */ diff --git a/tests/crypto-tls-psk-helpers.h b/tests/crypto-tls-psk-helpers.h new file mode 100644 index 0000000000..9aec29f1a0 --- /dev/null +++ b/tests/crypto-tls-psk-helpers.h @@ -0,0 +1,29 @@ +/* + * Copyright (C) 2015-2018 Red Hat, Inc. + * + * 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 2.1 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 + * . + * + * Author: Richard W.M. Jones + */ + +#include + +#ifdef QCRYPTO_HAVE_TLS_TEST_SUPPORT +# include "qemu-common.h" + +void test_tls_psk_init(const char *keyfile); +void test_tls_psk_cleanup(const char *keyfile); + +#endif /* QCRYPTO_HAVE_TLS_TEST_SUPPORT */ diff --git a/tests/test-crypto-tlssession.c b/tests/test-crypto-tlssession.c index 82f21c27f2..7bd811796e 100644 --- a/tests/test-crypto-tlssession.c +++ b/tests/test-crypto-tlssession.c @@ -21,7 +21,9 @@ #include "qemu/osdep.h" #include "crypto-tls-x509-helpers.h" +#include "crypto-tls-psk-helpers.h" #include "crypto/tlscredsx509.h" +#include "crypto/tlscredspsk.h" #include "crypto/tlssession.h" #include "qom/object_interfaces.h" #include "qapi/error.h" @@ -31,8 +33,152 @@ #ifdef QCRYPTO_HAVE_TLS_TEST_SUPPORT #define WORKDIR "tests/test-crypto-tlssession-work/" +#define PSKFILE WORKDIR "keys.psk" #define KEYFILE WORKDIR "key-ctx.pem" +static ssize_t testWrite(const char *buf, size_t len, void *opaque) +{ + int *fd = opaque; + + return write(*fd, buf, len); +} + +static ssize_t testRead(char *buf, size_t len, void *opaque) +{ + int *fd = opaque; + + return read(*fd, buf, len); +} + +static QCryptoTLSCreds *test_tls_creds_psk_create( + QCryptoTLSCredsEndpoint endpoint, + const char *dir, + Error **errp) +{ + Error *err = NULL; + Object *parent = object_get_objects_root(); + Object *creds = object_new_with_props( + TYPE_QCRYPTO_TLS_CREDS_PSK, + parent, + (endpoint == QCRYPTO_TLS_CREDS_ENDPOINT_SERVER ? + "testtlscredsserver" : "testtlscredsclient"), + &err, + "endpoint", (endpoint == QCRYPTO_TLS_CREDS_ENDPOINT_SERVER ? + "server" : "client"), + "dir", dir, + "priority", "NORMAL", + NULL + ); + + if (err) { + error_propagate(errp, err); + return NULL; + } + return QCRYPTO_TLS_CREDS(creds); +} + + +static void test_crypto_tls_session_psk(void) +{ + QCryptoTLSCreds *clientCreds; + QCryptoTLSCreds *serverCreds; + QCryptoTLSSession *clientSess = NULL; + QCryptoTLSSession *serverSess = NULL; + int channel[2]; + bool clientShake = false; + bool serverShake = false; + Error *err = NULL; + int ret; + + /* We'll use this for our fake client-server connection */ + ret = socketpair(AF_UNIX, SOCK_STREAM, 0, channel); + g_assert(ret == 0); + + /* + * We have an evil loop to do the handshake in a single + * thread, so we need these non-blocking to avoid deadlock + * of ourselves + */ + qemu_set_nonblock(channel[0]); + qemu_set_nonblock(channel[1]); + + clientCreds = test_tls_creds_psk_create( + QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT, + WORKDIR, + &err); + g_assert(clientCreds != NULL); + + serverCreds = test_tls_creds_psk_create( + QCRYPTO_TLS_CREDS_ENDPOINT_SERVER, + WORKDIR, + &err); + g_assert(serverCreds != NULL); + + /* Now the real part of the test, setup the sessions */ + clientSess = qcrypto_tls_session_new( + clientCreds, NULL, NULL, + QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT, &err); + serverSess = qcrypto_tls_session_new( + serverCreds, NULL, NULL, + QCRYPTO_TLS_CREDS_ENDPOINT_SERVER, &err); + + g_assert(clientSess != NULL); + g_assert(serverSess != NULL); + + /* For handshake to work, we need to set the I/O callbacks + * to read/write over the socketpair + */ + qcrypto_tls_session_set_callbacks(serverSess, + testWrite, testRead, + &channel[0]); + qcrypto_tls_session_set_callbacks(clientSess, + testWrite, testRead, + &channel[1]); + + /* + * Finally we loop around & around doing handshake on each + * session until we get an error, or the handshake completes. + * This relies on the socketpair being nonblocking to avoid + * deadlocking ourselves upon handshake + */ + do { + int rv; + if (!serverShake) { + rv = qcrypto_tls_session_handshake(serverSess, + &err); + g_assert(rv >= 0); + if (qcrypto_tls_session_get_handshake_status(serverSess) == + QCRYPTO_TLS_HANDSHAKE_COMPLETE) { + serverShake = true; + } + } + if (!clientShake) { + rv = qcrypto_tls_session_handshake(clientSess, + &err); + g_assert(rv >= 0); + if (qcrypto_tls_session_get_handshake_status(clientSess) == + QCRYPTO_TLS_HANDSHAKE_COMPLETE) { + clientShake = true; + } + } + } while (!clientShake && !serverShake); + + + /* Finally make sure the server & client validation is successful. */ + g_assert(qcrypto_tls_session_check_credentials(serverSess, &err) == 0); + g_assert(qcrypto_tls_session_check_credentials(clientSess, &err) == 0); + + object_unparent(OBJECT(serverCreds)); + object_unparent(OBJECT(clientCreds)); + + qcrypto_tls_session_free(serverSess); + qcrypto_tls_session_free(clientSess); + + close(channel[0]); + close(channel[1]); +} + + struct QCryptoTLSSessionTestData { const char *servercacrt; const char *clientcacrt; @@ -44,24 +190,10 @@ struct QCryptoTLSSessionTestData { const char *const *wildcards; }; - -static ssize_t testWrite(const char *buf, size_t len, void *opaque) -{ - int *fd = opaque; - - return write(*fd, buf, len); -} - -static ssize_t testRead(char *buf, size_t len, void *opaque) -{ - int *fd = opaque; - - return read(*fd, buf, len); -} - -static QCryptoTLSCreds *test_tls_creds_create(QCryptoTLSCredsEndpoint endpoint, - const char *certdir, - Error **errp) +static QCryptoTLSCreds *test_tls_creds_x509_create( + QCryptoTLSCredsEndpoint endpoint, + const char *certdir, + Error **errp) { Error *err = NULL; Object *parent = object_get_objects_root(); @@ -104,7 +236,7 @@ static QCryptoTLSCreds *test_tls_creds_create(QCryptoTLSCredsEndpoint endpoint, * initiate a TLS session across them. Finally do * do actual cert validation tests */ -static void test_crypto_tls_session(const void *opaque) +static void test_crypto_tls_session_x509(const void *opaque) { struct QCryptoTLSSessionTestData *data = (struct QCryptoTLSSessionTestData *)opaque; @@ -159,13 +291,13 @@ static void test_crypto_tls_session(const void *opaque) g_assert(link(KEYFILE, CLIENT_CERT_DIR QCRYPTO_TLS_CREDS_X509_CLIENT_KEY) == 0); - clientCreds = test_tls_creds_create( + clientCreds = test_tls_creds_x509_create( QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT, CLIENT_CERT_DIR, &err); g_assert(clientCreds != NULL); - serverCreds = test_tls_creds_create( + serverCreds = test_tls_creds_x509_create( QCRYPTO_TLS_CREDS_ENDPOINT_SERVER, SERVER_CERT_DIR, &err); @@ -285,7 +417,13 @@ int main(int argc, char **argv) mkdir(WORKDIR, 0700); test_tls_init(KEYFILE); + test_tls_psk_init(PSKFILE); + /* Simple initial test using Pre-Shared Keys. */ + g_test_add_func("/qcrypto/tlssession/psk", + test_crypto_tls_session_psk); + + /* More complex tests using X.509 certificates. */ # define TEST_SESS_REG(name, caCrt, \ serverCrt, clientCrt, \ expectServerFail, expectClientFail, \ @@ -296,7 +434,7 @@ int main(int argc, char **argv) hostname, wildcards \ }; \ g_test_add_data_func("/qcrypto/tlssession/" # name, \ - &name, test_crypto_tls_session); \ + &name, test_crypto_tls_session_x509); \ # define TEST_SESS_REG_EXT(name, serverCaCrt, clientCaCrt, \ @@ -309,7 +447,7 @@ int main(int argc, char **argv) hostname, wildcards \ }; \ g_test_add_data_func("/qcrypto/tlssession/" # name, \ - &name, test_crypto_tls_session); \ + &name, test_crypto_tls_session_x509); \ /* A perfect CA, perfect client & perfect server */ @@ -518,6 +656,7 @@ int main(int argc, char **argv) test_tls_discard_cert(&clientcertlevel2breq); unlink(WORKDIR "cacertchain-sess.pem"); + test_tls_psk_cleanup(PSKFILE); test_tls_cleanup(KEYFILE); rmdir(WORKDIR);