From patchwork Wed May 5 06:48:41 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vitaly Chikunov X-Patchwork-Id: 12239123 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B8B47C43460 for ; Wed, 5 May 2021 06:49:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8BC15613C1 for ; Wed, 5 May 2021 06:49:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231440AbhEEGu0 (ORCPT ); Wed, 5 May 2021 02:50:26 -0400 Received: from vmicros1.altlinux.org ([194.107.17.57]:59556 "EHLO vmicros1.altlinux.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229599AbhEEGu0 (ORCPT ); Wed, 5 May 2021 02:50:26 -0400 Received: from imap.altlinux.org (imap.altlinux.org [194.107.17.38]) by vmicros1.altlinux.org (Postfix) with ESMTP id 1CA7A72C8B5; Wed, 5 May 2021 09:49:29 +0300 (MSK) Received: from beacon.altlinux.org (unknown [193.43.10.250]) by imap.altlinux.org (Postfix) with ESMTPSA id F0E214A46E8; Wed, 5 May 2021 09:49:28 +0300 (MSK) From: Vitaly Chikunov To: Mimi Zohar , Dmitry Kasatkin , linux-integrity@vger.kernel.org Subject: [PATCH v4 1/3] ima-evm-utils: Allow manual setting keyid for signing Date: Wed, 5 May 2021 09:48:41 +0300 Message-Id: <20210505064843.111900-2-vt@altlinux.org> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20210505064843.111900-1-vt@altlinux.org> References: <20210505064843.111900-1-vt@altlinux.org> Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org Allow user to set signature's keyid using `--keyid' option. Keyid should correspond to SKID in certificate, when keyid is calculated using SHA-1 in libimaevm it may mismatch keyid extracted by the kernel from SKID of certificate (the way public key is presented to the kernel), thus making signatures not verifiable. This may happen when certificate is using non SHA-1 SKID (see rfc7093) or just 'unique number' (see rfc5280 4.2.1.2). As a last resort user may specify arbitrary keyid using the new option. This commit creates ABI change for libimaevm, because of adding additional parameter to imaevm_params - newer libimaevm cannot work with older clients. Signed-off-by: Vitaly Chikunov Reported-by: Elvira Khabirova Reviewed-by: Stefan Berger --- README | 1 + src/evmctl.c | 15 +++++++++++++++ src/imaevm.h | 1 + src/libimaevm.c | 8 +++++--- tests/sign_verify.test | 1 + 5 files changed, 23 insertions(+), 3 deletions(-) diff --git a/README b/README index 321045d..8cd66e0 100644 --- a/README +++ b/README @@ -48,6 +48,7 @@ OPTIONS --xattr-user store xattrs in user namespace (for testing purposes) --rsa use RSA key type and signing scheme v1 -k, --key path to signing key (default: /etc/keys/{privkey,pubkey}_evm.pem) + --keyid val overwrite signature keyid with a value (for signing) -o, --portable generate portable EVM signatures -p, --pass password for encrypted signing key -r, --recursive recurse into directories (sign) diff --git a/src/evmctl.c b/src/evmctl.c index 1815f55..8ae5488 100644 --- a/src/evmctl.c +++ b/src/evmctl.c @@ -2446,6 +2446,7 @@ static void usage(void) " --xattr-user store xattrs in user namespace (for testing purposes)\n" " --rsa use RSA key type and signing scheme v1\n" " -k, --key path to signing key (default: /etc/keys/{privkey,pubkey}_evm.pem)\n" + " --keyid val overwrite signature keyid with a value (for signing)\n" " -o, --portable generate portable EVM signatures\n" " -p, --pass password for encrypted signing key\n" " -r, --recursive recurse into directories (sign)\n" @@ -2525,6 +2526,7 @@ static struct option opts[] = { {"xattr-user", 0, 0, 140}, {"ignore-violations", 0, 0, 141}, {"pcrs", 1, 0, 142}, + {"keyid", 1, 0, 143}, {} }; @@ -2569,6 +2571,8 @@ int main(int argc, char *argv[]) { int err = 0, c, lind; ENGINE *eng = NULL; + unsigned long keyid; + char *eptr; #if !(OPENSSL_VERSION_NUMBER < 0x10100000) OPENSSL_init_crypto( @@ -2713,6 +2717,17 @@ int main(int argc, char *argv[]) } pcrfile[npcrfile++] = optarg; break; + case 143: + errno = 0; + keyid = strtoul(optarg, &eptr, 16); + if (errno || eptr - optarg != strlen(optarg) || + keyid == ULONG_MAX || keyid > UINT_MAX || + keyid == 0) { + log_err("Invalid keyid value.\n"); + exit(1); + } + imaevm_params.keyid = keyid; + break; case '?': exit(1); break; diff --git a/src/imaevm.h b/src/imaevm.h index 4503919..9f38059 100644 --- a/src/imaevm.h +++ b/src/imaevm.h @@ -196,6 +196,7 @@ struct libimaevm_params { const char *hash_algo; const char *keyfile; const char *keypass; + uint32_t keyid; /* keyid overriding value, unless 0. */ }; struct RSA_ASN1_template { diff --git a/src/libimaevm.c b/src/libimaevm.c index fa6c278..481d29d 100644 --- a/src/libimaevm.c +++ b/src/libimaevm.c @@ -45,6 +45,7 @@ #include #include #include +#include #include #include #include @@ -894,7 +895,6 @@ static int sign_hash_v2(const char *algo, const unsigned char *hash, const EVP_MD *md; size_t sigsize; const char *st; - uint32_t keyid; if (!hash) { log_err("sign_hash_v2: hash is null\n"); @@ -932,8 +932,10 @@ static int sign_hash_v2(const char *algo, const unsigned char *hash, return -1; } - calc_keyid_v2(&keyid, name, pkey); - hdr->keyid = keyid; + if (imaevm_params.keyid) + hdr->keyid = htonl(imaevm_params.keyid); + else + calc_keyid_v2(&hdr->keyid, name, pkey); st = "EVP_PKEY_CTX_new"; if (!(ctx = EVP_PKEY_CTX_new(pkey, NULL))) diff --git a/tests/sign_verify.test b/tests/sign_verify.test index 288e133..2c21812 100755 --- a/tests/sign_verify.test +++ b/tests/sign_verify.test @@ -359,6 +359,7 @@ sign_verify rsa1024 sha256 0x0301 --rsa sign_verify rsa1024 md5 0x030201:K:0080 sign_verify rsa1024 sha1 0x030202:K:0080 sign_verify rsa1024 sha224 0x030207:K:0080 +expect_pass check_sign TYPE=ima KEY=rsa1024 ALG=sha256 PREFIX=0x030204aabbccdd0080 OPTS=--keyid=aabbccdd sign_verify rsa1024 sha256 0x030204:K:0080 try_different_keys try_different_sigs From patchwork Wed May 5 06:48:42 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vitaly Chikunov X-Patchwork-Id: 12239125 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B366EC433ED for ; Wed, 5 May 2021 06:49:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 91A32613C1 for ; Wed, 5 May 2021 06:49:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231553AbhEEGua (ORCPT ); Wed, 5 May 2021 02:50:30 -0400 Received: from vmicros1.altlinux.org ([194.107.17.57]:59624 "EHLO vmicros1.altlinux.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230328AbhEEGua (ORCPT ); Wed, 5 May 2021 02:50:30 -0400 Received: from imap.altlinux.org (imap.altlinux.org [194.107.17.38]) by vmicros1.altlinux.org (Postfix) with ESMTP id 6686672C8B5; Wed, 5 May 2021 09:49:33 +0300 (MSK) Received: from beacon.altlinux.org (unknown [193.43.10.250]) by imap.altlinux.org (Postfix) with ESMTPSA id 25AE64A46E8; Wed, 5 May 2021 09:49:33 +0300 (MSK) From: Vitaly Chikunov To: Mimi Zohar , Dmitry Kasatkin , linux-integrity@vger.kernel.org Subject: [PATCH v4 2/3] ima-evm-utils: Allow manual setting keyid from a cert file Date: Wed, 5 May 2021 09:48:42 +0300 Message-Id: <20210505064843.111900-3-vt@altlinux.org> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20210505064843.111900-1-vt@altlinux.org> References: <20210505064843.111900-1-vt@altlinux.org> Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org Allow user to specify `--keyid @/path/to/cert.pem' to extract keyid from SKID of the certificate file. PEM or DER format is auto-detected. `--keyid' option is reused instead of adding a new option (like possible `--cert') to signify to the user it's only keyid extraction and nothing more. This commit creates ABI change for libimaevm, due to adding new function ima_read_keyid(). Newer clients cannot work with older libimaevm. Together with previous commit it creates backward-incompatible ABI change, thus soname should be incremented on release. Signed-off-by: Vitaly Chikunov --- README | 1 + src/evmctl.c | 22 ++++++++++--- src/imaevm.h | 1 + src/libimaevm.c | 85 ++++++++++++++++++++++++++++++++++++++++++++++++++ tests/sign_verify.test | 1 + 5 files changed, 105 insertions(+), 5 deletions(-) diff --git a/README b/README index 8cd66e0..0e1f6ba 100644 --- a/README +++ b/README @@ -49,6 +49,7 @@ OPTIONS --rsa use RSA key type and signing scheme v1 -k, --key path to signing key (default: /etc/keys/{privkey,pubkey}_evm.pem) --keyid val overwrite signature keyid with a value (for signing) + val is a x509 cert file if prefixed with '@' -o, --portable generate portable EVM signatures -p, --pass password for encrypted signing key -r, --recursive recurse into directories (sign) diff --git a/src/evmctl.c b/src/evmctl.c index 8ae5488..6a60599 100644 --- a/src/evmctl.c +++ b/src/evmctl.c @@ -42,6 +42,7 @@ #include #include #include +#include #include #include #include @@ -57,12 +58,14 @@ #include #include +#include #include #include #include #include #include #include +#include #include "hash_info.h" #include "pcr.h" #include "utils.h" @@ -2447,6 +2450,7 @@ static void usage(void) " --rsa use RSA key type and signing scheme v1\n" " -k, --key path to signing key (default: /etc/keys/{privkey,pubkey}_evm.pem)\n" " --keyid val overwrite signature keyid with a value (for signing)\n" + " val is a x509 cert file if prefixed with '@'\n" " -o, --portable generate portable EVM signatures\n" " -p, --pass password for encrypted signing key\n" " -r, --recursive recurse into directories (sign)\n" @@ -2572,7 +2576,6 @@ int main(int argc, char *argv[]) int err = 0, c, lind; ENGINE *eng = NULL; unsigned long keyid; - char *eptr; #if !(OPENSSL_VERSION_NUMBER < 0x10100000) OPENSSL_init_crypto( @@ -2718,10 +2721,19 @@ int main(int argc, char *argv[]) pcrfile[npcrfile++] = optarg; break; case 143: - errno = 0; - keyid = strtoul(optarg, &eptr, 16); - if (errno || eptr - optarg != strlen(optarg) || - keyid == ULONG_MAX || keyid > UINT_MAX || + if (optarg[0] == '@') { + keyid = ima_read_keyid(optarg + 1, NULL); + } else { + char *eptr; + + errno = 0; + keyid = strtoul(optarg, &eptr, 16); + if (eptr - optarg != strlen(optarg) || errno) { + log_err("Invalid keyid value.\n"); + exit(1); + } + } + if (keyid == ULONG_MAX || keyid > UINT_MAX || keyid == 0) { log_err("Invalid keyid value.\n"); exit(1); diff --git a/src/imaevm.h b/src/imaevm.h index 9f38059..eab7f32 100644 --- a/src/imaevm.h +++ b/src/imaevm.h @@ -219,6 +219,7 @@ EVP_PKEY *read_pub_pkey(const char *keyfile, int x509); void calc_keyid_v1(uint8_t *keyid, char *str, const unsigned char *pkey, int len); void calc_keyid_v2(uint32_t *keyid, char *str, EVP_PKEY *pkey); int key2bin(RSA *key, unsigned char *pub); +unsigned long ima_read_keyid(const char *certfile, uint32_t *keyid); int sign_hash(const char *algo, const unsigned char *hash, int size, const char *keyfile, const char *keypass, unsigned char *sig); int verify_hash(const char *file, const unsigned char *hash, int size, unsigned char *sig, int siglen); diff --git a/src/libimaevm.c b/src/libimaevm.c index 481d29d..a22d9bb 100644 --- a/src/libimaevm.c +++ b/src/libimaevm.c @@ -57,6 +57,7 @@ #include #include #include +#include #include #include "imaevm.h" @@ -748,6 +749,90 @@ void calc_keyid_v2(uint32_t *keyid, char *str, EVP_PKEY *pkey) X509_PUBKEY_free(pk); } +enum keyid_file_type { + KEYID_FILE_PEM_KEY = 0, + KEYID_FILE_UNK_CERT, +}; + +/* + * @is_cert: 1 - this is a x509 cert file (maybe PEM, maybe DER encoded); + * 0 - this is a PEM encoded private key file with possible appended + * x509 cert. + */ +static unsigned long _ima_read_keyid(const char *certfile, uint32_t *keyid, + enum keyid_file_type file_type) +{ + uint32_t keyid_raw; + const ASN1_OCTET_STRING *skid; + int skid_len; + X509 *x = NULL; + FILE *fp; + + if (!(fp = fopen(certfile, "r"))) { + log_err("read keyid: %s: Cannot open: %s\n", certfile, + strerror(errno)); + return -1; + } + if (!PEM_read_X509(fp, &x, NULL, NULL)) { + if (ERR_GET_REASON(ERR_peek_last_error()) == PEM_R_NO_START_LINE) { + ERR_clear_error(); + if (file_type == KEYID_FILE_PEM_KEY) { + log_debug("%s: x509 certificate not found\n", + certfile); + fclose(fp); + return -1; + } + rewind(fp); + d2i_X509_fp(fp, &x); + } + if (!x) { + ERR_print_errors_fp(stderr); + log_err("read keyid: %s: Error reading x509 certificate\n", + certfile); + fclose(fp); + return -1; + } + } + fclose(fp); + + if (!(skid = X509_get0_subject_key_id(x))) { + log_err("read keyid: %s: SKID not found\n", certfile); + goto err_free; + } + skid_len = ASN1_STRING_length(skid); + if (skid_len < sizeof(keyid_raw)) { + log_err("read keyid: %s: SKID too short (len %d)\n", certfile, + skid_len); + goto err_free; + } + memcpy(&keyid_raw, ASN1_STRING_get0_data(skid) + skid_len + - sizeof(keyid_raw), sizeof(keyid_raw)); + if (keyid) + memcpy(keyid, &keyid_raw, sizeof(*keyid)); + log_info("keyid %04x (from %s)\n", ntohl(keyid_raw), certfile); + return ntohl(keyid_raw); + +err_free: + X509_free(x); + return -1; +} + +/** + * ima_read_keyid() - Read 32-bit keyid from the cert file. + * @certfile: File possibly containing certificate in DER/PEM format. + * @keyid: Output keyid in network order. + * + * Try to read keyid from Subject Key Identifier (SKID) of certificate. + * Autodetect if cert is in PEM or DER encoding. + * + * Return: -1 (ULONG_MAX) on error; + * 32-bit keyid as unsigned integer in host order. + */ +unsigned long ima_read_keyid(const char *certfile, uint32_t *keyid) +{ + return _ima_read_keyid(certfile, keyid, KEYID_FILE_UNK_CERT); +} + static EVP_PKEY *read_priv_pkey(const char *keyfile, const char *keypass) { FILE *fp; diff --git a/tests/sign_verify.test b/tests/sign_verify.test index 2c21812..52ea33a 100755 --- a/tests/sign_verify.test +++ b/tests/sign_verify.test @@ -360,6 +360,7 @@ sign_verify rsa1024 md5 0x030201:K:0080 sign_verify rsa1024 sha1 0x030202:K:0080 sign_verify rsa1024 sha224 0x030207:K:0080 expect_pass check_sign TYPE=ima KEY=rsa1024 ALG=sha256 PREFIX=0x030204aabbccdd0080 OPTS=--keyid=aabbccdd +expect_pass check_sign TYPE=ima KEY=rsa1024 ALG=sha256 PREFIX=0x030204:K:0080 OPTS=--keyid=@test-rsa1024.cer sign_verify rsa1024 sha256 0x030204:K:0080 try_different_keys try_different_sigs From patchwork Wed May 5 06:48:43 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vitaly Chikunov X-Patchwork-Id: 12239127 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3EC29C433ED for ; Wed, 5 May 2021 06:49:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 13DC7613BE for ; Wed, 5 May 2021 06:49:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230328AbhEEGug (ORCPT ); Wed, 5 May 2021 02:50:36 -0400 Received: from vmicros1.altlinux.org ([194.107.17.57]:59728 "EHLO vmicros1.altlinux.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229599AbhEEGuf (ORCPT ); Wed, 5 May 2021 02:50:35 -0400 Received: from imap.altlinux.org (imap.altlinux.org [194.107.17.38]) by vmicros1.altlinux.org (Postfix) with ESMTP id 7034A72C8B5; Wed, 5 May 2021 09:49:38 +0300 (MSK) Received: from beacon.altlinux.org (unknown [193.43.10.250]) by imap.altlinux.org (Postfix) with ESMTPSA id A5B444A46E8; Wed, 5 May 2021 09:49:37 +0300 (MSK) From: Vitaly Chikunov To: Mimi Zohar , Dmitry Kasatkin , linux-integrity@vger.kernel.org Subject: [PATCH v4 3/3] ima-evm-utils: Read keyid from the cert appended to the key file Date: Wed, 5 May 2021 09:48:43 +0300 Message-Id: <20210505064843.111900-4-vt@altlinux.org> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20210505064843.111900-1-vt@altlinux.org> References: <20210505064843.111900-1-vt@altlinux.org> Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org Allow to have certificate appended to the private key of `--key' specified (PEM) file (for v2 signing) to facilitate reading of keyid from the associated cert. This will allow users to have private and public key as a single file. There is no check that public key form the cert matches associated private key. Signed-off-by: Vitaly Chikunov --- README | 3 +++ src/libimaevm.c | 8 +++++--- 2 files changed, 8 insertions(+), 3 deletions(-) diff --git a/README b/README index 0e1f6ba..ea11bde 100644 --- a/README +++ b/README @@ -127,6 +127,9 @@ for signing and importing the key. Second key format uses X509 DER encoded public key certificates and uses asymmetric key support in the kernel (since kernel 3.9). CONFIG_INTEGRITY_ASYMMETRIC_KEYS must be enabled (default). +For v2 signatures x509 certificate with the public key could be appended to the private +key (both are in PEM format) to properly determine its Subject Key Identifier (SKID). + Integrity keyrings ---------------- diff --git a/src/libimaevm.c b/src/libimaevm.c index a22d9bb..ac4bb46 100644 --- a/src/libimaevm.c +++ b/src/libimaevm.c @@ -1017,10 +1017,12 @@ static int sign_hash_v2(const char *algo, const unsigned char *hash, return -1; } - if (imaevm_params.keyid) + if (imaevm_params.keyid) { hdr->keyid = htonl(imaevm_params.keyid); - else - calc_keyid_v2(&hdr->keyid, name, pkey); + } else { + if (_ima_read_keyid(keyfile, &hdr->keyid, KEYID_FILE_PEM_KEY) == ULONG_MAX) + calc_keyid_v2(&hdr->keyid, name, pkey); + } st = "EVP_PKEY_CTX_new"; if (!(ctx = EVP_PKEY_CTX_new(pkey, NULL)))