From mboxrd@z Thu Jan 1 00:00:00 1970 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 E0685ECAAA1 for ; Fri, 2 Sep 2022 23:08:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229484AbiIBXIY (ORCPT ); Fri, 2 Sep 2022 19:08:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53540 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230401AbiIBXIY (ORCPT ); Fri, 2 Sep 2022 19:08:24 -0400 Received: from mx0b-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C332AF32C5 for ; Fri, 2 Sep 2022 16:08:21 -0700 (PDT) Received: from pps.filterd (m0127361.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 282MprZX024611; Fri, 2 Sep 2022 23:08:18 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=from : to : cc : subject : date : message-id : mime-version : content-transfer-encoding; s=pp1; bh=ACvGCS10ZUs4A/Ey5tLCkHiBPbs58mC8ksyY7E9Shi0=; b=p6xqkifNkseHbSI90LTjj/nbAiPuUJDREXftd9fHdi1z7BIl6md2z/1h2yN8HgztJagf v78Rjogi3z6vrfGNU0j5o0CdGUIomTQiuiD7VGHVjCGADtkDic+/KAyc4pqEfbtn7MVk wFickj3weHueGnAGq8FYd4od6qCX8FYXCelgHgppAtuKKd0HhQiZsNxsvHe/k+lscefu fdQQqLTC/Fi65FR36M9/69OT7Hop/eHCjmrscUH4IKS3rPB7kqkBfpsxuM5ADsN1nXEm S9QNyUFzcvObL2zTVCPZmfXVRKYzYVokVwqinQXLOvkt0w/GRux85NoMPdJfgI7hPDrK Xw== Received: from ppma02dal.us.ibm.com (a.bd.3ea9.ip4.static.sl-reverse.com [169.62.189.10]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3jbu0gra7h-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 02 Sep 2022 23:08:18 +0000 Received: from pps.filterd (ppma02dal.us.ibm.com [127.0.0.1]) by ppma02dal.us.ibm.com (8.16.1.2/8.16.1.2) with SMTP id 282N6E0n026192; Fri, 2 Sep 2022 23:08:17 GMT Received: from b01cxnp23034.gho.pok.ibm.com (b01cxnp23034.gho.pok.ibm.com [9.57.198.29]) by ppma02dal.us.ibm.com with ESMTP id 3j7awadcfg-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 02 Sep 2022 23:08:17 +0000 Received: from b01ledav004.gho.pok.ibm.com (b01ledav004.gho.pok.ibm.com [9.57.199.109]) by b01cxnp23034.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 282N8GDX2294290 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 2 Sep 2022 23:08:16 GMT Received: from b01ledav004.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id B0345112063; Fri, 2 Sep 2022 23:08:16 +0000 (GMT) Received: from b01ledav004.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 78E68112062; Fri, 2 Sep 2022 23:08:16 +0000 (GMT) Received: from localhost.localdomain (unknown [9.77.134.254]) by b01ledav004.gho.pok.ibm.com (Postfix) with ESMTP; Fri, 2 Sep 2022 23:08:16 +0000 (GMT) From: Tergel Myanganbayar To: linux-integrity@vger.kernel.org Cc: Tergel Myanganbayar , Mimi Zohar , Petr Vorel , Stefan Berger , Tergel Myanganbayar Subject: [PATCH ima-evm-utils] add support for reading per bank TPM 2.0 PCRs via sysfs Date: Fri, 2 Sep 2022 19:08:15 -0400 Message-Id: <20220902230815.35448-1-tergel@linux.ibm.com> X-Mailer: git-send-email 2.32.1 (Apple Git-133) MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Proofpoint-GUID: sWV8j4gzj4rOOMC90pl_4h3eecg8N44N X-Proofpoint-ORIG-GUID: sWV8j4gzj4rOOMC90pl_4h3eecg8N44N X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.895,Hydra:6.0.517,FMLib:17.11.122.1 definitions=2022-09-02_06,2022-08-31_03,2022-06-22_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxlogscore=999 mlxscore=0 malwarescore=0 bulkscore=0 suspectscore=0 spamscore=0 adultscore=0 impostorscore=0 lowpriorityscore=0 priorityscore=1501 clxscore=1011 phishscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2207270000 definitions=main-2209020103 Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org Until Linux kernel version 5.11, a TSS was required to read TPM 2.0 PCR values. A feature which exposed the per bank TPM 2.0 PCRs directly via sysfs was upstreamed in newer Kernel versions. Use this recent feature in IMA-EVM-UTILS to remove TSS dependency. Signed-off-by: Tergel Myanganbayar --- src/evmctl.c | 53 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 53 insertions(+) diff --git a/src/evmctl.c b/src/evmctl.c index 46a34cc..d5fe988 100644 --- a/src/evmctl.c +++ b/src/evmctl.c @@ -1899,6 +1899,7 @@ static int read_one_bank(struct tpm_bank_info *tpm_bank, FILE *fp) static char *pcrs = "/sys/class/tpm/tpm0/device/pcrs"; /* Kernels >= 4.0 */ static char *misc_pcrs = "/sys/class/misc/tpm0/device/pcrs"; +static char tpm2_pcr_path[28] = "/sys/class/tpm/tpm0/pcr-sha"; /* Read one of the TPM 1.2 sysfs files if present */ static int read_sysfs_pcrs(int num_banks, struct tpm_bank_info *tpm_banks) @@ -1922,7 +1923,55 @@ static int read_sysfs_pcrs(int num_banks, struct tpm_bank_info *tpm_banks) for (i = 1; i < num_banks; i++) tpm_banks[i].supported = 0; return 0; +} + +static int read_tpm2_one_bank(struct tpm_bank_info *tpm_bank, int bank) +{ + FILE *fp; + char file_name[NAME_MAX]; + char digest[MAX_DIGEST_SIZE + 1]; + char *p; + int i; + + for (i = 0; i < NUM_PCRS; i++) { + sprintf(file_name, "%s%d/%d", tpm2_pcr_path, bank, i); + fp = fopen(file_name, "r"); + if (!fp) + return -1; + + p = fgets(digest, (tpm_bank->digest_size * 2 + 1), fp); + if (!p) + return -1; + + hex2bin(tpm_bank->pcr[i], digest, tpm_bank->digest_size); + fclose(fp); + } + return 0; +} + +static int read_sysfs_tpm2_pcrs(int num_banks, struct tpm_bank_info *tpm_banks) +{ + int banks[2] = {1, 256}; + int rt, j; + int tpm_enabled = 0; + if (imaevm_params.verbose > LOG_INFO) + log_info("Trying to read TPM 2.0 PCRs via sysfs.\n"); + + for (j = 0; j < num_banks; j++) { + rt = read_tpm2_one_bank(&tpm_banks[j], banks[j]); + tpm_banks[j].supported = 0; + + if (rt < 0) + continue; + + tpm_enabled = 1; + tpm_banks[j].supported = 1; + } + + if (tpm_enabled == 0) + return -1; + return 0; } /* Read PCRs from per-bank file(s) specified via --pcrs */ @@ -2008,6 +2057,9 @@ static int read_tpm_banks(int num_banks, struct tpm_bank_info *bank) if (read_sysfs_pcrs(num_banks, bank) == 0) return 0; + if (read_sysfs_tpm2_pcrs(num_banks, bank) == 0) + return 0; + /* Any userspace applications available for reading TPM 2.0 PCRs? */ if (!tpm2_pcr_supported()) { log_debug("Failed to read TPM 2.0 PCRs\n"); @@ -2024,6 +2076,7 @@ static int read_tpm_banks(int num_banks, struct tpm_bank_info *bank) bank[i].pcr[pcr_handle], bank[i].digest_size, &errmsg); + bank[i].supported = 1; if (err) { log_debug("Failed to read %s PCRs: (%s)\n", bank[i].algo_name, errmsg); -- 2.32.1 (Apple Git-133)