From patchwork Sun Nov 19 16:50:40 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mimi Zohar X-Patchwork-Id: 13460494 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=ibm.com header.i=@ibm.com header.b="NxMxZFXf" Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3CD6911A for ; Sun, 19 Nov 2023 08:51:09 -0800 (PST) Received: from pps.filterd (m0356517.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 3AJGAbES012838 for ; Sun, 19 Nov 2023 16:51:09 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding; s=pp1; bh=zzWqt7hAhOLEJyzTcvtJBkb2JUZLezTzCsPX1S5FZpY=; b=NxMxZFXfWpwFvliGkPNumul/RTMJA5IwItKd3Ol0ZZrlMoYfirHoq461dWWBM0xdVJoL Rjlet6Jsxy+rh0st7/ZiigXXZF1hv1QLCk4GpPcrU6wm4Lkst/IRgeHyIuSpY6fjADyP 7hKCSgNmvObtgatZt6CcitDJio0jzDAiOUeTyurPJohod12GRox7G69HqAQFARHi6bQC ScXm3OQW5tmw7TVdBjeylFQdT5S3/w+vjPyx4/i/SCToYAA3ww4rcx9pmWAlVmxEAPq5 /ONmedeVlpV2pGt3jMpSfIFeKsC553ovHK+dCaGUzyikiJ1TAZcKZMwm691WEPpUwZXY IA== Received: from ppma12.dal12v.mail.ibm.com (dc.9e.1632.ip4.static.sl-reverse.com [50.22.158.220]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3uf1f6rcd8-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT) for ; Sun, 19 Nov 2023 16:51:08 +0000 Received: from pps.filterd (ppma12.dal12v.mail.ibm.com [127.0.0.1]) by ppma12.dal12v.mail.ibm.com (8.17.1.19/8.17.1.19) with ESMTP id 3AJE6Jq0021000 for ; Sun, 19 Nov 2023 16:51:07 GMT Received: from smtprelay06.fra02v.mail.ibm.com ([9.218.2.230]) by ppma12.dal12v.mail.ibm.com (PPS) with ESMTPS id 3uf7ksmbgv-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT) for ; Sun, 19 Nov 2023 16:51:07 +0000 Received: from smtpav06.fra02v.mail.ibm.com (smtpav06.fra02v.mail.ibm.com [10.20.54.105]) by smtprelay06.fra02v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 3AJGp4b143713120 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Sun, 19 Nov 2023 16:51:04 GMT Received: from smtpav06.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id BAA7220049; Sun, 19 Nov 2023 16:51:04 +0000 (GMT) Received: from smtpav06.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id D706720040; Sun, 19 Nov 2023 16:51:03 +0000 (GMT) Received: from li-f45666cc-3089-11b2-a85c-c57d1a57929f.ibm.com.com (unknown [9.61.134.108]) by smtpav06.fra02v.mail.ibm.com (Postfix) with ESMTP; Sun, 19 Nov 2023 16:51:03 +0000 (GMT) From: Mimi Zohar To: linux-integrity@vger.kernel.org Cc: Mimi Zohar Subject: [ima-evm-utils PATCH 09/12] Use a local hash algorithm variable when verifying file signatures Date: Sun, 19 Nov 2023 11:50:40 -0500 Message-Id: <20231119165043.46960-10-zohar@linux.ibm.com> X-Mailer: git-send-email 2.39.3 In-Reply-To: <20231119165043.46960-1-zohar@linux.ibm.com> References: <20231119165043.46960-1-zohar@linux.ibm.com> Precedence: bulk X-Mailing-List: linux-integrity@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-GUID: RURGaFTzopUBr96rCFirr8T1P7PBzUsx X-Proofpoint-ORIG-GUID: RURGaFTzopUBr96rCFirr8T1P7PBzUsx X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.987,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2023-11-19_15,2023-11-17_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 adultscore=0 mlxlogscore=999 priorityscore=1501 lowpriorityscore=0 clxscore=1015 phishscore=0 mlxscore=0 spamscore=0 bulkscore=0 suspectscore=0 impostorscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2311060000 definitions=main-2311190129 Instead of relying on the "imaevm_params.algo" global variable, which is not concurrency-safe, define and use a local variable. Update static verify_hash_v2(), verify_hash_v3(), and verify_hash_common() function definitions to include a hash algorithm argument. Similarly update ima_verify_signature2() and ima_calc_hash2() to define and use a local hash algorithm variable. Signed-off-by: Mimi Zohar --- src/libimaevm.c | 40 ++++++++++++++++++++++++---------------- 1 file changed, 24 insertions(+), 16 deletions(-) diff --git a/src/libimaevm.c b/src/libimaevm.c index 4c9da7a2f06b..18b6a6f27237 100644 --- a/src/libimaevm.c +++ b/src/libimaevm.c @@ -488,6 +488,7 @@ void init_public_keys(const char *keyfiles) * (Note: signature_v2_hdr struct does not contain the 'type'.) */ static int verify_hash_common(void *public_keys, const char *file, + const char *hash_algo, const unsigned char *hash, int size, unsigned char *sig, int siglen) { @@ -499,7 +500,7 @@ static int verify_hash_common(void *public_keys, const char *file, const char *st; if (imaevm_params.verbose > LOG_INFO) { - log_info("hash(%s): ", imaevm_params.hash_algo); + log_info("hash(%s): ", hash_algo); log_dump(hash, size); } @@ -530,7 +531,7 @@ static int verify_hash_common(void *public_keys, const char *file, if (!EVP_PKEY_verify_init(ctx)) goto err; st = "EVP_get_digestbyname"; - if (!(md = EVP_get_digestbyname(imaevm_params.hash_algo))) + if (!(md = EVP_get_digestbyname(hash_algo))) goto err; st = "EVP_PKEY_CTX_set_signature_md"; if (!EVP_PKEY_CTX_set_signature_md(ctx, md)) @@ -566,11 +567,12 @@ err: * Return: 0 verification good, 1 verification bad, -1 error. */ static int verify_hash_v2(void *public_keys, const char *file, + const char *hash_algo, const unsigned char *hash, int size, unsigned char *sig, int siglen) { /* note: signature_v2_hdr does not contain 'type', use sig + 1 */ - return verify_hash_common(public_keys, file, hash, size, + return verify_hash_common(public_keys, file, hash_algo, hash, size, sig + 1, siglen - 1); } @@ -581,19 +583,20 @@ static int verify_hash_v2(void *public_keys, const char *file, * Return: 0 verification good, 1 verification bad, -1 error. */ static int verify_hash_v3(void *public_keys, const char *file, + const char *hash_algo, const unsigned char *hash, int size, unsigned char *sig, int siglen) { unsigned char sigv3_hash[MAX_DIGEST_SIZE]; int ret; - ret = calc_hash_sigv3(sig[0], NULL, hash, sigv3_hash); + ret = calc_hash_sigv3(sig[0], hash_algo, hash, sigv3_hash); if (ret < 0) return ret; /* note: signature_v2_hdr does not contain 'type', use sig + 1 */ - return verify_hash_common(public_keys, file, sigv3_hash, size, - sig + 1, siglen - 1); + return verify_hash_common(public_keys, file, hash_algo, sigv3_hash, + size, sig + 1, siglen - 1); } #define HASH_MAX_DIGESTSIZE 64 /* kernel HASH_MAX_DIGESTSIZE is 64 bytes */ @@ -636,8 +639,10 @@ int calc_hash_sigv3(enum evm_ima_xattr_type type, const char *algo, return -EINVAL; } - if (!algo) - algo = imaevm_params.hash_algo; + if (!algo) { + log_err("Hash algorithm unspecified\n"); + return -EINVAL; + } if ((hash_algo = imaevm_get_hash_algo(algo)) < 0) { log_err("Hash algorithm %s not supported\n", algo); @@ -757,10 +762,10 @@ int verify_hash2(void *public_keys, const char *file, const char *hash_algo, return -1; #endif } else if (sig[1] == DIGSIG_VERSION_2) { - return verify_hash_v2(public_keys, file, hash, size, + return verify_hash_v2(public_keys, file, hash_algo, hash, size, sig, siglen); } else if (sig[1] == DIGSIG_VERSION_3) { - return verify_hash_v3(public_keys, file, hash, size, + return verify_hash_v3(public_keys, file, hash_algo, hash, size, sig, siglen); } else return -1; @@ -774,7 +779,8 @@ int verify_hash2(void *public_keys, const char *file, const char *hash_algo, int verify_hash(const char *file, const unsigned char *hash, int size, unsigned char *sig, int siglen) { - return verify_hash2(g_public_keys, file, NULL, hash, size, sig, siglen); + return verify_hash2(g_public_keys, file, imaevm_params.hash_algo, + hash, size, sig, siglen); } int ima_verify_signature2(void *public_keys, const char *file, @@ -783,6 +789,7 @@ int ima_verify_signature2(void *public_keys, const char *file, { unsigned char hash[MAX_DIGEST_SIZE]; int hashlen, sig_hash_algo; + const char *hash_algo; if (sig[0] != EVM_IMA_XATTR_DIGSIG && sig[0] != IMA_VERITY_DIGSIG) { log_err("%s: xattr ima has no signature\n", file); @@ -800,22 +807,23 @@ int ima_verify_signature2(void *public_keys, const char *file, return -1; } /* Use hash algorithm as retrieved from signature */ - imaevm_params.hash_algo = imaevm_hash_algo_by_id(sig_hash_algo); + hash_algo = imaevm_hash_algo_by_id(sig_hash_algo); /* * Validate the signature based on the digest included in the * measurement list, not by calculating the local file digest. */ if (digest && digestlen > 0) - return verify_hash2(public_keys, file, NULL, digest, digestlen, - sig, siglen); + return verify_hash2(public_keys, file, + hash_algo, digest, digestlen, + sig, siglen); - hashlen = ima_calc_hash(file, hash); + hashlen = ima_calc_hash2(file, hash_algo, hash); if (hashlen <= 1) return hashlen; assert(hashlen <= sizeof(hash)); - return verify_hash2(public_keys, file, NULL, hash, hashlen, + return verify_hash2(public_keys, file, hash_algo, hash, hashlen, sig, siglen); }