From patchwork Mon Nov 15 19:34:20 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Gonda X-Patchwork-Id: 12620359 X-Patchwork-Delegate: herbert@gondor.apana.org.au Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0001DC433EF for ; Mon, 15 Nov 2021 20:26:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D72596323A for ; Mon, 15 Nov 2021 20:26:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350742AbhKOUZh (ORCPT ); Mon, 15 Nov 2021 15:25:37 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39746 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347484AbhKOTj7 (ORCPT ); Mon, 15 Nov 2021 14:39:59 -0500 Received: from mail-yb1-xb49.google.com (mail-yb1-xb49.google.com [IPv6:2607:f8b0:4864:20::b49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 92034C06122C for ; Mon, 15 Nov 2021 11:34:24 -0800 (PST) Received: by mail-yb1-xb49.google.com with SMTP id v133-20020a25c58b000000b005c20153475dso28265351ybe.17 for ; Mon, 15 Nov 2021 11:34:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:message-id:mime-version:subject:from:to:cc; bh=aGpK0n+S3Cv9bjNDEf/KmKHHm2D/FjmK7hXeVTFlz/Q=; b=YeUVYlPI1o2XyKC0lUT6UO6bcdDPQenFfuZiT/x6Ts/+02Q69ZDJfBjXSIt7LRnMwq 33GPPLXmgRE8bD5BvhWpK+Vy0FDWjUq27I2b3V3MFb3XVhy3F8X1H6Y7kzoZfk9yeS1b OWKTVci3FkU1lwXkmjUnk+QI1Rt+4Rj5h8vLFL0xlWgfRLC6F3s1zcTztLcRDFd3/czK h15fasakXJqlIq/VjjFlKCHs9zR3cofwZq0YQRYN8Um3XhA6ASWNNbIiP8ckkptBv3G5 3dZ+ES8D3CYTGTKA5O5rGwnrnMBCPqfjMZi7dZYhbajvzWKLIqaUVODrL4Xz6hg98M0D AL5w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:message-id:mime-version:subject:from:to:cc; bh=aGpK0n+S3Cv9bjNDEf/KmKHHm2D/FjmK7hXeVTFlz/Q=; b=rdVrJuRd1/cJDT13rjzzzRtoy3HbN9lEKZqGAbwch7/R7s9wmbSghbYrM5ksoyFfcC 9PXwU6PES9BOjA5V2sPaMCNLjbJdXhtc/ur97VOYANMuACFVA6cD/2jYJNI5jD/FjLlK 8zDm77v7GJHVhd/duaBfn6AD7AWZPYKuhFfPEPqDIeBrzW4qtjKIhCH2EJ+mwjiYNLUZ F/Se3qZu2RJ/l2tEZA8CbHyDEP59HRjnjwZNWBMJQFZ+Ip8JpsP19Z+s6zkL4z88wKQf Qsa1Z5EF5pbXhpOOjH1uFUuIAVAUHI4gN87ysjl3Ly6Rhn5RsOcCUwkh/d/P+aAdzAq6 djvg== X-Gm-Message-State: AOAM5306acRbVy/qpN29jVeSDyPsSTf52p/wdcsUBGcN2+QG6PNhEXrN 16F97lJmXbp3k0NpJkNimHrv+eV3+UY= X-Google-Smtp-Source: ABdhPJwAk3Pef2Gs4wryc7PpFonYd0ZcZr1JsoV+FWUcjb1NlLsnZu6YPaiymBXfR27xEvQze0FWpLVHzf4= X-Received: from pgonda1.kir.corp.google.com ([2620:15c:29:204:9fb:192e:3671:218c]) (user=pgonda job=sendgmr) by 2002:a25:a2c1:: with SMTP id c1mr1485206ybn.473.1637004863853; Mon, 15 Nov 2021 11:34:23 -0800 (PST) Date: Mon, 15 Nov 2021 11:34:20 -0800 Message-Id: <20211115193420.2288308-1-pgonda@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.34.0.rc1.387.gb447b232ab-goog Subject: [PATCH V4.1 5/5] crypto: ccp - Add SEV_INIT_EX support From: Peter Gonda To: thomas.lendacky@amd.com Cc: David Rientjes , Peter Gonda , Marc Orr , Brijesh Singh , Joerg Roedel , Herbert Xu , John Allen , "David S. Miller" , Paolo Bonzini , linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org From: David Rientjes Add new module parameter to allow users to use SEV_INIT_EX instead of SEV_INIT. This helps users who lock their SPI bus to use the PSP for SEV functionality. The 'init_ex_path' parameter defaults to NULL which means the kernel will use SEV_INIT, if a path is specified SEV_INIT_EX will be used with the data found at the path. On certain PSP commands this file is written to as the PSP updates the NV memory region. Depending on file system initialization this file open may fail during module init but the CCP driver for SEV already has sufficient retries for platform initialization. During normal operation of PSP system and SEV commands if the PSP has not been initialized it is at run time. If the file at 'init_ex_path' does not exist the PSP will not be initialized. The user must create the file prior to use with 32Kb of 0xFFs per spec. Signed-off-by: David Rientjes Co-developed-by: Peter Gonda Signed-off-by: Peter Gonda Reviewed-by: Marc Orr Cc: Tom Lendacky Cc: Brijesh Singh Cc: Marc Orr Cc: Joerg Roedel Cc: Herbert Xu Cc: David Rientjes Cc: John Allen Cc: "David S. Miller" Cc: Paolo Bonzini Cc: linux-crypto@vger.kernel.org Cc: linux-kernel@vger.kernel.org --- V4.1 * Fixed missing loff_t paramter for kernel_read(). -- .../virt/kvm/amd-memory-encryption.rst | 6 + drivers/crypto/ccp/sev-dev.c | 194 ++++++++++++++++-- include/linux/psp-sev.h | 21 ++ 3 files changed, 206 insertions(+), 15 deletions(-) diff --git a/Documentation/virt/kvm/amd-memory-encryption.rst b/Documentation/virt/kvm/amd-memory-encryption.rst index 5c081c8c7164..1c6847fff304 100644 --- a/Documentation/virt/kvm/amd-memory-encryption.rst +++ b/Documentation/virt/kvm/amd-memory-encryption.rst @@ -85,6 +85,12 @@ guests, such as launching, running, snapshotting, migrating and decommissioning. The KVM_SEV_INIT command is used by the hypervisor to initialize the SEV platform context. In a typical workflow, this command should be the first command issued. +The firmware can be initialized either by using its own non-volatile storage or +the OS can manage the NV storage for the firmware using the module parameter +``init_ex_path``. The file specified by ``init_ex_path`` must exist. To create +a new NV storage file allocate the file with 32KB bytes of 0xFF as required by +the SEV spec. + Returns: 0 on success, -negative on error 2. KVM_SEV_LAUNCH_START diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c index ee9f194d460e..5e32fd44f804 100644 --- a/drivers/crypto/ccp/sev-dev.c +++ b/drivers/crypto/ccp/sev-dev.c @@ -22,6 +22,7 @@ #include #include #include +#include #include @@ -43,6 +44,10 @@ static int psp_probe_timeout = 5; module_param(psp_probe_timeout, int, 0644); MODULE_PARM_DESC(psp_probe_timeout, " default timeout value, in seconds, during PSP device probe"); +static char *init_ex_path; +module_param(init_ex_path, charp, 0444); +MODULE_PARM_DESC(init_ex_path, " Path for INIT_EX data; if set try INIT_EX"); + static bool psp_init_on_probe = true; module_param(psp_init_on_probe, bool, 0444); MODULE_PARM_DESC(psp_init_on_probe, " if true, the PSP will be initialized on module init. Else the PSP will be initialized on the first command requiring it"); @@ -62,6 +67,14 @@ static int psp_timeout; #define SEV_ES_TMR_SIZE (1024 * 1024) static void *sev_es_tmr; +/* INIT_EX NV Storage: + * The NV Storage is a 32Kb area and must be 4Kb page aligned. Use the page + * allocator to allocate the memory, which will return aligned memory for the + * specified allocation order. + */ +#define NV_LENGTH (32 * 1024) +static void *sev_init_ex_buffer; + static inline bool sev_version_greater_or_equal(u8 maj, u8 min) { struct sev_device *sev = psp_master->sev_data; @@ -111,6 +124,7 @@ static int sev_cmd_buffer_len(int cmd) { switch (cmd) { case SEV_CMD_INIT: return sizeof(struct sev_data_init); + case SEV_CMD_INIT_EX: return sizeof(struct sev_data_init_ex); case SEV_CMD_PLATFORM_STATUS: return sizeof(struct sev_user_data_status); case SEV_CMD_PEK_CSR: return sizeof(struct sev_data_pek_csr); case SEV_CMD_PEK_CERT_IMPORT: return sizeof(struct sev_data_pek_cert_import); @@ -156,6 +170,102 @@ static void *sev_fw_alloc(unsigned long len) return page_address(page); } +static int sev_read_init_ex_file(void) +{ + struct sev_device *sev = psp_master->sev_data; + struct file *fp; + ssize_t nread; + loff_t pos = 0; + + lockdep_assert_held(sev_cmd_mutex); + + if (!sev_init_ex_buffer) + return -EOPNOTSUPP; + + fp = filp_open(init_ex_path, O_RDONLY, 0); + if (IS_ERR(fp)) { + int ret = PTR_ERR(fp); + + dev_err(sev->dev, + "SEV: could not open %s for read, error %d\n", + init_ex_path, ret); + return ret; + } + + nread = kernel_read(fp, sev_init_ex_buffer, NV_LENGTH, &pos); + if (nread != NV_LENGTH) { + dev_err(sev->dev, + "SEV: failed to read %u bytes to non volatile memory area, ret %ld\n", + NV_LENGTH, nread); + return -EIO; + } + + dev_dbg(sev->dev, "SEV: read %ld bytes from NV file\n", nread); + filp_close(fp, NULL); + + return 0; +} + +static void sev_write_init_ex_file(void) +{ + struct sev_device *sev = psp_master->sev_data; + struct file *fp; + loff_t offset = 0; + ssize_t nwrite; + + lockdep_assert_held(sev_cmd_mutex); + + if (!sev_init_ex_buffer) + return; + + fp = filp_open(init_ex_path, O_CREAT | O_WRONLY, 0600); + if (IS_ERR(fp)) { + dev_err(sev->dev, + "SEV: could not open file for write, error %d\n", + PTR_ERR(fp)); + return; + } + + nwrite = kernel_write(fp, sev_init_ex_buffer, NV_LENGTH, &offset); + vfs_fsync(fp, 0); + filp_close(fp, NULL); + + if (nwrite != NV_LENGTH) { + dev_err(sev->dev, + "SEV: failed to write %u bytes to non volatile memory area, ret %ld\n", + NV_LENGTH, nwrite); + return; + } + + dev_dbg(sev->dev, "SEV: write successful to NV file\n"); +} + +static void sev_write_init_ex_file_if_required(int cmd_id) +{ + lockdep_assert_held(sev_cmd_mutex); + + if (!sev_init_ex_buffer) + return; + + /* + * Only a few platform commands modify the SPI/NV area, but none of the + * non-platform commands do. Only INIT(_EX), PLATFORM_RESET, PEK_GEN, + * PEK_CERT_IMPORT, and PDH_GEN do. + */ + switch (cmd_id) { + case SEV_CMD_FACTORY_RESET: + case SEV_CMD_INIT_EX: + case SEV_CMD_PDH_GEN: + case SEV_CMD_PEK_CERT_IMPORT: + case SEV_CMD_PEK_GEN: + break; + default: + return; + }; + + sev_write_init_ex_file(); +} + static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret) { struct psp_device *psp = psp_master; @@ -225,6 +335,8 @@ static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret) dev_dbg(sev->dev, "sev command %#x failed (%#010x)\n", cmd, reg & PSP_CMDRESP_ERR_MASK); ret = -EIO; + } else { + sev_write_init_ex_file_if_required(cmd); } print_hex_dump_debug("(out): ", DUMP_PREFIX_OFFSET, 16, 2, data, @@ -251,37 +363,71 @@ static int sev_do_cmd(int cmd, void *data, int *psp_ret) return rc; } -static int __sev_platform_init_locked(int *error) +static int __sev_init_locked(int *error) { - struct psp_device *psp = psp_master; struct sev_data_init data; - struct sev_device *sev; - int psp_ret, rc = 0; - if (!psp || !psp->sev_data) - return -ENODEV; + memset(&data, 0, sizeof(data)); + if (sev_es_tmr) { + /* + * Do not include the encryption mask on the physical + * address of the TMR (firmware should clear it anyway). + */ + data.tmr_address = __pa(sev_es_tmr); - sev = psp->sev_data; + data.flags |= SEV_INIT_FLAGS_SEV_ES; + data.tmr_len = SEV_ES_TMR_SIZE; + } - if (sev->state == SEV_STATE_INIT) - return 0; + return __sev_do_cmd_locked(SEV_CMD_INIT, &data, error); +} + +static int __sev_init_ex_locked(int *error) +{ + struct sev_data_init_ex data; + int ret; memset(&data, 0, sizeof(data)); - if (sev_es_tmr) { - u64 tmr_pa; + data.length = sizeof(data); + data.nv_address = __psp_pa(sev_init_ex_buffer); + data.nv_len = NV_LENGTH; + ret = sev_read_init_ex_file(); + if (ret) + return ret; + + if (sev_es_tmr) { /* * Do not include the encryption mask on the physical * address of the TMR (firmware should clear it anyway). */ - tmr_pa = __pa(sev_es_tmr); + data.tmr_address = __pa(sev_es_tmr); data.flags |= SEV_INIT_FLAGS_SEV_ES; - data.tmr_address = tmr_pa; data.tmr_len = SEV_ES_TMR_SIZE; } - rc = __sev_do_cmd_locked(SEV_CMD_INIT, &data, &psp_ret); + return __sev_do_cmd_locked(SEV_CMD_INIT_EX, &data, error); +} + +static int __sev_platform_init_locked(int *error) +{ + struct psp_device *psp = psp_master; + struct sev_device *sev; + int rc, psp_ret; + int (*init_function)(int *error); + + if (!psp || !psp->sev_data) + return -ENODEV; + + sev = psp->sev_data; + + if (sev->state == SEV_STATE_INIT) + return 0; + + init_function = sev_init_ex_buffer ? __sev_init_ex_locked : + __sev_init_locked; + rc = init_function(&psp_ret); if (rc && psp_ret == SEV_RET_SECURE_DATA_INVALID) { /* * Initialization command returned an integrity check failure @@ -291,7 +437,7 @@ static int __sev_platform_init_locked(int *error) * with a reset state. */ dev_dbg(sev->dev, "SEV: retrying INIT command"); - rc = __sev_do_cmd_locked(SEV_CMD_INIT, &data, &psp_ret); + rc = init_function(&psp_ret); } if (error) *error = psp_ret; @@ -1066,6 +1212,12 @@ static void sev_firmware_shutdown(struct sev_device *sev) get_order(SEV_ES_TMR_SIZE)); sev_es_tmr = NULL; } + + if (sev_init_ex_buffer) { + free_pages((unsigned long)sev_init_ex_buffer, + get_order(NV_LENGTH)); + sev_init_ex_buffer = NULL; + } } void sev_dev_destroy(struct psp_device *psp) @@ -1111,6 +1263,18 @@ void sev_pci_init(void) sev_update_firmware(sev->dev) == 0) sev_get_api_version(); + /* If an init_ex_path is provided rely on INIT_EX for PSP initialization + * instead of INIT. + */ + if (init_ex_path) { + sev_init_ex_buffer = sev_fw_alloc(NV_LENGTH); + if (!sev_init_ex_buffer) { + dev_err(sev->dev, + "SEV: INIT_EX NV memory allocation failed\n"); + goto err; + } + } + /* Obtain the TMR memory area for SEV-ES use */ sev_es_tmr = sev_fw_alloc(SEV_ES_TMR_SIZE); if (!sev_es_tmr) diff --git a/include/linux/psp-sev.h b/include/linux/psp-sev.h index d48a7192e881..1595088c428b 100644 --- a/include/linux/psp-sev.h +++ b/include/linux/psp-sev.h @@ -52,6 +52,7 @@ enum sev_cmd { SEV_CMD_DF_FLUSH = 0x00A, SEV_CMD_DOWNLOAD_FIRMWARE = 0x00B, SEV_CMD_GET_ID = 0x00C, + SEV_CMD_INIT_EX = 0x00D, /* Guest commands */ SEV_CMD_DECOMMISSION = 0x020, @@ -102,6 +103,26 @@ struct sev_data_init { u32 tmr_len; /* In */ } __packed; +/** + * struct sev_data_init_ex - INIT_EX command parameters + * + * @length: len of the command buffer read by the PSP + * @flags: processing flags + * @tmr_address: system physical address used for SEV-ES + * @tmr_len: len of tmr_address + * @nv_address: system physical address used for PSP NV storage + * @nv_len: len of nv_address + */ +struct sev_data_init_ex { + u32 length; /* In */ + u32 flags; /* In */ + u64 tmr_address; /* In */ + u32 tmr_len; /* In */ + u32 reserved; /* In */ + u64 nv_address; /* In/Out */ + u32 nv_len; /* In */ +} __packed; + #define SEV_INIT_FLAGS_SEV_ES 0x01 /**