From patchwork Wed May 4 23:20:55 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Evan Green X-Patchwork-Id: 12838888 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 121BEC4332F for ; Wed, 4 May 2022 23:35:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234492AbiEDXhu (ORCPT ); Wed, 4 May 2022 19:37:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41702 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1359803AbiEDXZK (ORCPT ); Wed, 4 May 2022 19:25:10 -0400 Received: from mail-pg1-x529.google.com (mail-pg1-x529.google.com [IPv6:2607:f8b0:4864:20::529]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 75B034DF55 for ; Wed, 4 May 2022 16:21:32 -0700 (PDT) Received: by mail-pg1-x529.google.com with SMTP id k14so2353836pga.0 for ; Wed, 04 May 2022 16:21:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=Yhdb5Bb/HPOT7rt6ZFl1SIPi2sOZMgAuPW9HJM+UwR0=; b=Lk4xT28VP//2/ipug2hDVNsFxT9ZIxqyDHb0zfUWgwzqxrDXikdUEYcZVll3q4j94i ztdggJgt0+wJWipyAMzuue+sqAj5cr1iqrjXU6TY0KlGJi2k7/sLjz4SzJeD6C1FqUri Vuh+XJBEfDQcKfui50SG/RlDJ8yjXNcYwrQew= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=Yhdb5Bb/HPOT7rt6ZFl1SIPi2sOZMgAuPW9HJM+UwR0=; b=AHUT/tOG5zmcdFjQ7MmMF+PWq9INbR+aN/lUkCPkUvmV16cmU5p5YiGePB0etDeXAf 6BagmD6KUEwbl5QtR0AOlVhS+rav83lyn+UWCE/gcEx5vyAjWetswN3/KX14C5F1dfqK h4jAI6iJ+RCNrbGLhq6V9kPuLKU77ipWD7Tbxku2n/nAg4I2vXpXKNhjkWHFCeZaJ5Eg YN1OMHj8B+Q3nCP3vnPtcoQjvqbOJ7NbjKBegfw5QRvcMMlL8bPFdEXWeEsiSox4h8vs 9oOiUPwM6rDOWiuop9aTa4Uwx7cORzZ2qMBjYzsYJgyqxuCYVL6E4ydasBrRpLXAxioz nxnA== X-Gm-Message-State: AOAM533W0Zb1lA7U05RzgyIaY9l2gV+0+ZEBjJTQcTxaZLotsZeALbB6 AmGlMxg+N4ZMqTaiiW3hl6eiPw== X-Google-Smtp-Source: ABdhPJw5P1NIDRBbT4jMlDGJLeiA/MnnIE6iVTPAa0LCmNhzVLp/2G2suU9nzhm2DtywpArEruqEYA== X-Received: by 2002:a62:ce82:0:b0:50d:512f:7b76 with SMTP id y124-20020a62ce82000000b0050d512f7b76mr23214566pfg.79.1651706491900; Wed, 04 May 2022 16:21:31 -0700 (PDT) Received: from evgreen-glaptop.lan ([98.47.98.87]) by smtp.gmail.com with ESMTPSA id q12-20020a170902f78c00b0015e8d4eb2d6sm1901pln.288.2022.05.04.16.21.30 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 04 May 2022 16:21:31 -0700 (PDT) From: Evan Green To: linux-kernel@vger.kernel.org Cc: Matthew Garrett , dlunev@google.com, zohar@linux.ibm.com, jejb@linux.ibm.com, linux-integrity@vger.kernel.org, corbet@lwn.net, rjw@rjwysocki.net, gwendal@chromium.org, jarkko@kernel.org, linux-pm@vger.kernel.org, Matthew Garrett , Matthew Garrett , Evan Green , David Howells , James Morris , "Serge E. Hallyn" , keyrings@vger.kernel.org, linux-security-module@vger.kernel.org Subject: [PATCH 03/10] security: keys: trusted: Parse out individual components of the key blob Date: Wed, 4 May 2022 16:20:55 -0700 Message-Id: <20220504161439.3.Id409e0cf397bd98b76df6eb60ff16454679dd23d@changeid> X-Mailer: git-send-email 2.31.0 In-Reply-To: <20220504232102.469959-1-evgreen@chromium.org> References: <20220504232102.469959-1-evgreen@chromium.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: keyrings@vger.kernel.org From: Matthew Garrett Performing any sort of state validation of a sealed TPM blob requires being able to access the individual members in the response. Parse the blob sufficiently to be able to stash pointers to each member, along with the length. From: Matthew Garrett Signed-off-by: Matthew Garrett Signed-off-by: Evan Green --- Matthew's original version of this patch is at: https://patchwork.kernel.org/patch/12096489/ include/keys/trusted-type.h | 8 +++ security/keys/trusted-keys/trusted_tpm2.c | 67 ++++++++++++++++++++++- 2 files changed, 73 insertions(+), 2 deletions(-) diff --git a/include/keys/trusted-type.h b/include/keys/trusted-type.h index d89fa2579ac056..8a793ae1ad9f70 100644 --- a/include/keys/trusted-type.h +++ b/include/keys/trusted-type.h @@ -22,15 +22,23 @@ #define MAX_BLOB_SIZE 512 #define MAX_PCRINFO_SIZE 64 #define MAX_DIGEST_SIZE 64 +#define MAX_CREATION_DATA 412 +#define MAX_TK 76 struct trusted_key_payload { struct rcu_head rcu; unsigned int key_len; unsigned int blob_len; + unsigned int creation_len; + unsigned int creation_hash_len; + unsigned int tk_len; unsigned char migratable; unsigned char old_format; unsigned char key[MAX_KEY_SIZE + 1]; unsigned char blob[MAX_BLOB_SIZE]; + unsigned char *creation; + unsigned char *creation_hash; + unsigned char *tk; }; struct trusted_key_options { diff --git a/security/keys/trusted-keys/trusted_tpm2.c b/security/keys/trusted-keys/trusted_tpm2.c index 0165da386289c3..296a00f872ba40 100644 --- a/security/keys/trusted-keys/trusted_tpm2.c +++ b/security/keys/trusted-keys/trusted_tpm2.c @@ -215,6 +215,63 @@ static void tpm2_buf_append_auth(struct tpm_buf *buf, u32 session_handle, tpm_buf_append(buf, hmac, hmac_len); } +static int tpm2_unpack_blob(struct trusted_key_payload *payload) +{ + int tmp, offset; + + /* Find the length of the private data */ + tmp = be16_to_cpup((__be16 *) &payload->blob[0]); + offset = tmp + 2; + if (offset > payload->blob_len) + return -EFAULT; + + /* Find the length of the public data */ + tmp = be16_to_cpup((__be16 *) &payload->blob[offset]); + offset += tmp + 2; + if (offset > payload->blob_len) + return -EFAULT; + + /* Find the length of the creation data and store it */ + tmp = be16_to_cpup((__be16 *) &payload->blob[offset]); + if (tmp > MAX_CREATION_DATA) + return -E2BIG; + + if ((offset + tmp + 2) > payload->blob_len) + return -EFAULT; + + payload->creation = &payload->blob[offset + 2]; + payload->creation_len = tmp; + offset += tmp + 2; + + /* Find the length of the creation hash and store it */ + tmp = be16_to_cpup((__be16 *) &payload->blob[offset]); + if (tmp > MAX_DIGEST_SIZE) + return -E2BIG; + + if ((offset + tmp + 2) > payload->blob_len) + return -EFAULT; + + payload->creation_hash = &payload->blob[offset + 2]; + payload->creation_hash_len = tmp; + offset += tmp + 2; + + /* + * Store the creation ticket. TPMT_TK_CREATION is two bytes of tag, + * four bytes of handle, and then the digest length and digest data + */ + tmp = be16_to_cpup((__be16 *) &payload->blob[offset + 6]); + if (tmp > MAX_TK) + return -E2BIG; + + if ((offset + tmp + 8) > payload->blob_len) + return -EFAULT; + + payload->tk = &payload->blob[offset]; + payload->tk_len = tmp + 8; + + return 0; +} + /** * tpm2_seal_trusted() - seal the payload of a trusted key * @@ -229,6 +286,7 @@ int tpm2_seal_trusted(struct tpm_chip *chip, struct trusted_key_options *options) { int blob_len = 0; + unsigned int offset; struct tpm_buf buf; u32 hash; u32 flags; @@ -317,15 +375,17 @@ int tpm2_seal_trusted(struct tpm_chip *chip, rc = -E2BIG; goto out; } - if (tpm_buf_length(&buf) < TPM_HEADER_SIZE + 4 + blob_len) { + offset = TPM_HEADER_SIZE + 4; + if (tpm_buf_length(&buf) < offset + blob_len) { rc = -EFAULT; goto out; } blob_len = tpm2_key_encode(payload, options, - &buf.data[TPM_HEADER_SIZE + 4], + &buf.data[offset], blob_len); + rc = tpm2_unpack_blob(payload); out: tpm_buf_destroy(&buf); @@ -431,7 +491,10 @@ static int tpm2_load_cmd(struct tpm_chip *chip, if (!rc) *blob_handle = be32_to_cpup( (__be32 *) &buf.data[TPM_HEADER_SIZE]); + else + goto out; + rc = tpm2_unpack_blob(payload); out: if (blob != payload->blob) kfree(blob); From patchwork Wed May 4 23:20:56 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Evan Green X-Patchwork-Id: 12838887 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E1F4FC433FE for ; Wed, 4 May 2022 23:35:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234940AbiEDXhu (ORCPT ); Wed, 4 May 2022 19:37:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41796 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1379753AbiEDXZO (ORCPT ); Wed, 4 May 2022 19:25:14 -0400 Received: from mail-pj1-x1036.google.com (mail-pj1-x1036.google.com [IPv6:2607:f8b0:4864:20::1036]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 57E554EA0B for ; Wed, 4 May 2022 16:21:36 -0700 (PDT) Received: by mail-pj1-x1036.google.com with SMTP id r9so2569948pjo.5 for ; Wed, 04 May 2022 16:21:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=oSCDp+BlWHOAe2tqoHinPSSzUxabaz3SWirbYWgZ7iE=; b=AK96nFD2jq9As8QRqe4ZZgrKB3muSxd4UKPDu0PiPgxZCEkF09YM3a/lbxSE2Aolhc 8/11YUs8xGSuIa13K4FNjPmrXP32NRaFX2/fqhw5ycNjYisg1PBFJZiM4dKkwgF7l4SI 8V/qwibG9N2Kolpq0e2PDsUZD0WN7jb8AqoT4= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=oSCDp+BlWHOAe2tqoHinPSSzUxabaz3SWirbYWgZ7iE=; b=w1Xnl8Cvv4Are6fUKeEtxgZyA+EbzRRlTyuqMBeepXDJJjkbuNRJT5+qhRsaBf7Hy7 8UGkq1JT3hyMyPnJUjF8Mmo7vORAgH2WRN5axTNTxJh0oQVKJ/uOiHuDo1BWUxTug/Dj 6tsfx7xTDgzQPNc+vrcmf0Ri3GNO5XEHbBXDedGgiLvBDsYoh+jT4lcj1Tts5lfYb3NU 2DXfkB/62lHPMhl60Lk6guUQmi8jp0ZHa+ACjU3eDLJihGyxBgbw2sVjbTXamVGgUAm7 kmpHPjoOwrIXBWOmzkqQF0LeHqsb9FEgGxUUeOJwc+X6FckD4zd+kJrVfOw7It2lmG4J tTQg== X-Gm-Message-State: AOAM532qFFTa6HkoMdHP8zFI+zOjN/K1rd3+tOIOo1HzyFEodMr/pIIY XIGXPnQzKmqM+4mL+DWFrUbOZg== X-Google-Smtp-Source: ABdhPJyWCNX/I16qyW4fvcathhxcuAgJ0GjSbW0c5vLuKr3I6Bnp2rIZfhNKLxSoEtDyFcQM2HOpmw== X-Received: by 2002:a17:902:7e01:b0:15e:caea:d6 with SMTP id b1-20020a1709027e0100b0015ecaea00d6mr4372912plm.33.1651706495884; Wed, 04 May 2022 16:21:35 -0700 (PDT) Received: from evgreen-glaptop.lan ([98.47.98.87]) by smtp.gmail.com with ESMTPSA id q12-20020a170902f78c00b0015e8d4eb2d6sm1901pln.288.2022.05.04.16.21.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 04 May 2022 16:21:35 -0700 (PDT) From: Evan Green To: linux-kernel@vger.kernel.org Cc: Matthew Garrett , dlunev@google.com, zohar@linux.ibm.com, jejb@linux.ibm.com, linux-integrity@vger.kernel.org, corbet@lwn.net, rjw@rjwysocki.net, gwendal@chromium.org, jarkko@kernel.org, linux-pm@vger.kernel.org, Matthew Garrett , Matthew Garrett , Evan Green , David Howells , James Morris , "Serge E. Hallyn" , keyrings@vger.kernel.org, linux-doc@vger.kernel.org, linux-security-module@vger.kernel.org Subject: [PATCH 04/10] security: keys: trusted: Allow storage of PCR values in creation data Date: Wed, 4 May 2022 16:20:56 -0700 Message-Id: <20220504161439.4.I32591db064b6cdc91850d777f363c9d05c985b39@changeid> X-Mailer: git-send-email 2.31.0 In-Reply-To: <20220504232102.469959-1-evgreen@chromium.org> References: <20220504232102.469959-1-evgreen@chromium.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: keyrings@vger.kernel.org From: Matthew Garrett When TPMs generate keys, they can also generate some information describing the state of the PCRs at creation time. This data can then later be certified by the TPM, allowing verification of the PCR values. This allows us to determine the state of the system at the time a key was generated. Add an additional argument to the trusted key creation options, allowing the user to provide the set of PCRs that should have their values incorporated into the creation data. From: Matthew Garrett Signed-off-by: Matthew Garrett Signed-off-by: Evan Green --- Matthew's original version of this patch is at: https://patchwork.kernel.org/patch/12096503/ .../security/keys/trusted-encrypted.rst | 4 +++ include/keys/trusted-type.h | 1 + security/keys/trusted-keys/trusted_tpm1.c | 9 +++++++ security/keys/trusted-keys/trusted_tpm2.c | 25 +++++++++++++++++-- 4 files changed, 37 insertions(+), 2 deletions(-) diff --git a/Documentation/security/keys/trusted-encrypted.rst b/Documentation/security/keys/trusted-encrypted.rst index f614dad7de12f9..7215b067bf128f 100644 --- a/Documentation/security/keys/trusted-encrypted.rst +++ b/Documentation/security/keys/trusted-encrypted.rst @@ -170,6 +170,10 @@ Usage:: policyhandle= handle to an authorization policy session that defines the same policy and with the same hash algorithm as was used to seal the key. + creationpcrs= hex integer representing the set of PCR values to be + included in the PCR creation data. The bit corresponding + to each PCR should be 1 to be included, 0 to be ignored. + TPM2 only. "keyctl print" returns an ascii hex copy of the sealed key, which is in standard TPM_STORED_DATA format. The key length for new keys are always in bytes. diff --git a/include/keys/trusted-type.h b/include/keys/trusted-type.h index 8a793ae1ad9f70..b3ac4afe8ba987 100644 --- a/include/keys/trusted-type.h +++ b/include/keys/trusted-type.h @@ -54,6 +54,7 @@ struct trusted_key_options { uint32_t policydigest_len; unsigned char policydigest[MAX_DIGEST_SIZE]; uint32_t policyhandle; + uint32_t creation_pcrs; }; struct trusted_key_ops { diff --git a/security/keys/trusted-keys/trusted_tpm1.c b/security/keys/trusted-keys/trusted_tpm1.c index aa108bea6739b3..2975827c01bec0 100644 --- a/security/keys/trusted-keys/trusted_tpm1.c +++ b/security/keys/trusted-keys/trusted_tpm1.c @@ -713,6 +713,7 @@ enum { Opt_hash, Opt_policydigest, Opt_policyhandle, + Opt_creationpcrs, }; static const match_table_t key_tokens = { @@ -725,6 +726,7 @@ static const match_table_t key_tokens = { {Opt_hash, "hash=%s"}, {Opt_policydigest, "policydigest=%s"}, {Opt_policyhandle, "policyhandle=%s"}, + {Opt_creationpcrs, "creationpcrs=%s"}, {Opt_err, NULL} }; @@ -858,6 +860,13 @@ static int getoptions(char *c, struct trusted_key_payload *pay, return -EINVAL; opt->policyhandle = handle; break; + case Opt_creationpcrs: + if (!tpm2) + return -EINVAL; + res = kstrtoint(args[0].from, 16, &opt->creation_pcrs); + if (res < 0) + return -EINVAL; + break; default: return -EINVAL; } diff --git a/security/keys/trusted-keys/trusted_tpm2.c b/security/keys/trusted-keys/trusted_tpm2.c index 296a00f872ba40..b7ddb78e644d17 100644 --- a/security/keys/trusted-keys/trusted_tpm2.c +++ b/security/keys/trusted-keys/trusted_tpm2.c @@ -290,7 +290,7 @@ int tpm2_seal_trusted(struct tpm_chip *chip, struct tpm_buf buf; u32 hash; u32 flags; - int i; + int i, j; int rc; for (i = 0; i < ARRAY_SIZE(tpm2_hash_map); i++) { @@ -359,7 +359,28 @@ int tpm2_seal_trusted(struct tpm_chip *chip, tpm_buf_append_u16(&buf, 0); /* creation PCR */ - tpm_buf_append_u32(&buf, 0); + if (options->creation_pcrs) { + /* One bank */ + tpm_buf_append_u32(&buf, 1); + /* Which bank to use */ + tpm_buf_append_u16(&buf, hash); + /* Length of the PCR bitmask */ + tpm_buf_append_u8(&buf, 3); + /* PCR bitmask */ + for (i = 0; i < 3; i++) { + char tmp = 0; + + for (j = 0; j < 8; j++) { + char bit = (i * 8) + j; + + if (options->creation_pcrs & (1 << bit)) + tmp |= (1 << j); + } + tpm_buf_append_u8(&buf, tmp); + } + } else { + tpm_buf_append_u32(&buf, 0); + } if (buf.flags & TPM_BUF_OVERFLOW) { rc = -E2BIG; From patchwork Wed May 4 23:20:57 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Evan Green X-Patchwork-Id: 12838886 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2A048C433EF for ; Wed, 4 May 2022 23:34:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231783AbiEDXhq (ORCPT ); Wed, 4 May 2022 19:37:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41930 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1383888AbiEDXZQ (ORCPT ); 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Hallyn" , axelj , keyrings@vger.kernel.org, linux-security-module@vger.kernel.org Subject: [PATCH 05/10] security: keys: trusted: Verify creation data Date: Wed, 4 May 2022 16:20:57 -0700 Message-Id: <20220504161439.5.I6cdb522cb5ea28fcd1e35b4cd92cbd067f99269a@changeid> X-Mailer: git-send-email 2.31.0 In-Reply-To: <20220504232102.469959-1-evgreen@chromium.org> References: <20220504232102.469959-1-evgreen@chromium.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: keyrings@vger.kernel.org If a loaded key contains creation data, ask the TPM to verify that creation data. This allows users like encrypted hibernate to know that the loaded and parsed creation data has not been tampered with. Partially-sourced-from: Matthew Garrett Signed-off-by: Evan Green --- Source material for this change is at: https://patchwork.kernel.org/project/linux-pm/patch/20210220013255.1083202-9-matthewgarrett@google.com/ include/linux/tpm.h | 1 + security/keys/trusted-keys/trusted_tpm2.c | 72 ++++++++++++++++++++++- 2 files changed, 72 insertions(+), 1 deletion(-) diff --git a/include/linux/tpm.h b/include/linux/tpm.h index 8320cbac6f4009..438f8bc0a50582 100644 --- a/include/linux/tpm.h +++ b/include/linux/tpm.h @@ -224,6 +224,7 @@ enum tpm2_command_codes { TPM2_CC_SELF_TEST = 0x0143, TPM2_CC_STARTUP = 0x0144, TPM2_CC_SHUTDOWN = 0x0145, + TPM2_CC_CERTIFYCREATION = 0x014A, TPM2_CC_NV_READ = 0x014E, TPM2_CC_CREATE = 0x0153, TPM2_CC_LOAD = 0x0157, diff --git a/security/keys/trusted-keys/trusted_tpm2.c b/security/keys/trusted-keys/trusted_tpm2.c index b7ddb78e644d17..6db30a5fc320c0 100644 --- a/security/keys/trusted-keys/trusted_tpm2.c +++ b/security/keys/trusted-keys/trusted_tpm2.c @@ -600,6 +600,69 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip, return rc; } +/** + * tpm2_certify_creation() - execute a TPM2_CertifyCreation command + * + * @chip: TPM chip to use + * @payload: the key data in clear and encrypted form + * @blob_handle: the loaded TPM handle of the key + * + * Return: 0 on success + * -EINVAL on tpm error status + * < 0 error from tpm_send or tpm_buf_init + */ +static int tpm2_certify_creation(struct tpm_chip *chip, + struct trusted_key_payload *payload, + u32 blob_handle) +{ + struct tpm_header *head; + struct tpm_buf buf; + int rc; + + rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_CERTIFYCREATION); + if (rc) + return rc; + + /* Use TPM_RH_NULL for signHandle */ + tpm_buf_append_u32(&buf, 0x40000007); + + /* Object handle */ + tpm_buf_append_u32(&buf, blob_handle); + + /* Auth */ + tpm_buf_append_u32(&buf, 9); + tpm_buf_append_u32(&buf, TPM2_RS_PW); + tpm_buf_append_u16(&buf, 0); + tpm_buf_append_u8(&buf, 0); + tpm_buf_append_u16(&buf, 0); + + /* Qualifying data */ + tpm_buf_append_u16(&buf, 0); + + /* Creation data hash */ + tpm_buf_append_u16(&buf, payload->creation_hash_len); + tpm_buf_append(&buf, payload->creation_hash, + payload->creation_hash_len); + + /* signature scheme */ + tpm_buf_append_u16(&buf, TPM_ALG_NULL); + + /* creation ticket */ + tpm_buf_append(&buf, payload->tk, payload->tk_len); + + rc = tpm_transmit_cmd(chip, &buf, 6, "certifying creation data"); + if (rc) + goto out; + + head = (struct tpm_header *)buf.data; + + if (head->return_code != 0) + rc = -EINVAL; +out: + tpm_buf_destroy(&buf); + return rc; +} + /** * tpm2_unseal_trusted() - unseal the payload of a trusted key * @@ -625,8 +688,15 @@ int tpm2_unseal_trusted(struct tpm_chip *chip, goto out; rc = tpm2_unseal_cmd(chip, payload, options, blob_handle); - tpm2_flush_context(chip, blob_handle); + if (rc) + goto flush; + + if (payload->creation_len) + rc = tpm2_certify_creation(chip, payload, blob_handle); + +flush: + tpm2_flush_context(chip, blob_handle); out: tpm_put_ops(chip);