From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=ibm.com header.i=@ibm.com header.b="raeBa3b0" Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id ECB51112 for ; Wed, 22 Nov 2023 06:14:34 -0800 (PST) Received: from pps.filterd (m0353728.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 3AMDkEuS009945 for ; Wed, 22 Nov 2023 14:14:34 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=message-id : subject : from : to : date : in-reply-to : references : content-type : mime-version : content-transfer-encoding; s=pp1; bh=RdG928/iU0O9WL//gJA4kYwhEW6Yn5ktoD8QQcwvFKs=; b=raeBa3b0sLthogPNehWFwEis3TWTflJviunG5UA9az24Hj93t5hIUErQHyrRG+eocvfw PIQRy4aPBNkPRITYQLMqa9wWDRxjMRJy8zUKAHc7h2Jaot6EKmtglHCyZh0hqEsB1vGW hmFR3ok9B44FzKhsBCAErHBfqbVQvDic6uuVWp1b+dUfiPbLcjM7d93ywY1CHtIBvSvB 5OIh1prPQdDMMUfyDA/EvtYtXS1KNdnVR119FVC95j9NX6chFzOpbU09BO2Vt1a0pB8M U04dBOEU6X6N2lttEMtEveTE2sjTpEJ4LNhnyQ6GWkPtSjKTtRlR2e2eYUUKsykc2vkU Zg== Received: from ppma13.dal12v.mail.ibm.com (dd.9e.1632.ip4.static.sl-reverse.com [50.22.158.221]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3uhj8qhh07-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT) for ; 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Wed, 22 Nov 2023 14:14:32 +0000 (GMT) Received: from li-f45666cc-3089-11b2-a85c-c57d1a57929f.ibm.com (unknown [9.61.71.187]) by smtpav03.wdc07v.mail.ibm.com (Postfix) with ESMTP; Wed, 22 Nov 2023 14:14:32 +0000 (GMT) Message-ID: Subject: Re: [ima-evm-utils PATCH 09/12] Use a local hash algorithm variable when verifying file signatures From: Mimi Zohar To: Stefan Berger , linux-integrity@vger.kernel.org Date: Wed, 22 Nov 2023 09:14:31 -0500 In-Reply-To: <93aa5f57-fd8a-475f-a1b8-c8d00772b251@linux.ibm.com> References: <20231119165043.46960-1-zohar@linux.ibm.com> <20231119165043.46960-10-zohar@linux.ibm.com> <93aa5f57-fd8a-475f-a1b8-c8d00772b251@linux.ibm.com> Content-Type: text/plain; charset="ISO-8859-15" X-Mailer: Evolution 3.28.5 (3.28.5-22.el8) Precedence: bulk X-Mailing-List: linux-integrity@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Proofpoint-GUID: gucfE8GGaCv_0xWpR_yw6sSH0sRxMSRk X-Proofpoint-ORIG-GUID: gucfE8GGaCv_0xWpR_yw6sSH0sRxMSRk 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=2023-11-22_09,2023-11-22_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 bulkscore=0 impostorscore=0 malwarescore=0 priorityscore=1501 mlxscore=0 clxscore=1015 mlxlogscore=999 lowpriorityscore=0 spamscore=0 phishscore=0 adultscore=0 suspectscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2311060000 definitions=main-2311220101 On Wed, 2023-11-22 at 08:37 -0500, Stefan Berger wrote: > > On 11/19/23 11:50, Mimi Zohar wrote: > > 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); > > Now you are passing valid parameters into verify_hash2(). Would it not > be possible to drop 4/12? Just as we can't modify the library verify_hash() definition, I don't think we should be modifying the verify_hash2() defintion either. 04/12 defines and exports the final verify_hash2() definition. -- thanks, Mimi