From patchwork Tue May 4 04:33:55 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vitaly Chikunov X-Patchwork-Id: 12237333 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,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 07A6FC433ED for ; Tue, 4 May 2021 04:35:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C709C611AD for ; Tue, 4 May 2021 04:35:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229737AbhEDEf5 (ORCPT ); Tue, 4 May 2021 00:35:57 -0400 Received: from vmicros1.altlinux.org ([194.107.17.57]:35502 "EHLO vmicros1.altlinux.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229735AbhEDEfz (ORCPT ); Tue, 4 May 2021 00:35:55 -0400 Received: from imap.altlinux.org (imap.altlinux.org [194.107.17.38]) by vmicros1.altlinux.org (Postfix) with ESMTP id 77CCE72C8B5; Tue, 4 May 2021 07:35:00 +0300 (MSK) Received: from beacon.altlinux.org (unknown [193.43.10.250]) by imap.altlinux.org (Postfix) with ESMTPSA id 5B68C4A46E8; Tue, 4 May 2021 07:35:00 +0300 (MSK) From: Vitaly Chikunov To: Mimi Zohar , Dmitry Kasatkin , linux-integrity@vger.kernel.org Cc: Elvira Khabirova Subject: [PATCH v2 1/3] ima-evm-utils: Allow manual setting keyid for signing Date: Tue, 4 May 2021 07:33:55 +0300 Message-Id: <20210504043357.4093409-2-vt@altlinux.org> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20210504043357.4093409-1-vt@altlinux.org> References: <20210504043357.4093409-1-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 backward compatible ABI change for libimaevm, because of adding additional parameter to imaevm_params - older libimaevm can work with newer client. Signed-off-by: Vitaly Chikunov Reported-by: Elvira Khabirova Reviewed-by: Stefan Berger --- README | 1 + src/evmctl.c | 14 ++++++++++++++ src/imaevm.h | 1 + src/libimaevm.c | 8 +++++--- tests/sign_verify.test | 1 + 5 files changed, 22 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..7983299 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 int keyid; + char *eptr; #if !(OPENSSL_VERSION_NUMBER < 0x10100000) OPENSSL_init_crypto( @@ -2713,6 +2717,16 @@ 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 > 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 Tue May 4 04:33:56 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vitaly Chikunov X-Patchwork-Id: 12237335 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,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 1F443C433B4 for ; Tue, 4 May 2021 04:35:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D6859611AC for ; Tue, 4 May 2021 04:35:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229735AbhEDEgE (ORCPT ); Tue, 4 May 2021 00:36:04 -0400 Received: from vmicros1.altlinux.org ([194.107.17.57]:35578 "EHLO vmicros1.altlinux.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229715AbhEDEgD (ORCPT ); Tue, 4 May 2021 00:36:03 -0400 Received: from imap.altlinux.org (imap.altlinux.org [194.107.17.38]) by vmicros1.altlinux.org (Postfix) with ESMTP id 08F3E72C8BA; Tue, 4 May 2021 07:35:08 +0300 (MSK) Received: from beacon.altlinux.org (unknown [193.43.10.250]) by imap.altlinux.org (Postfix) with ESMTPSA id C85B94A46E8; Tue, 4 May 2021 07:35:07 +0300 (MSK) From: Vitaly Chikunov To: Mimi Zohar , Dmitry Kasatkin , linux-integrity@vger.kernel.org Cc: Elvira Khabirova Subject: [PATCH v2 2/3] ima-evm-utils: Allow manual setting keyid from a cert file Date: Tue, 4 May 2021 07:33:56 +0300 Message-Id: <20210504043357.4093409-3-vt@altlinux.org> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20210504043357.4093409-1-vt@altlinux.org> References: <20210504043357.4093409-1-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. Signed-off-by: Vitaly Chikunov --- README | 1 + src/evmctl.c | 82 +++++++++++++++++++++++++++++++++++++++++++++++--- tests/sign_verify.test | 1 + 3 files changed, 79 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 7983299..fdb0fb3 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" @@ -2567,12 +2571,71 @@ static char *get_password(void) return pwd; } +/* Return true if FILE is possibly PEM encoded (otherwise DER). */ +static int is_encoding_pem(FILE *in) +{ + char buf[6]; /* Room for the 5 minus signs and '\0'. */ + int pem = 0; + + if (fgets(buf, sizeof(buf), in) && + strspn(buf, "-") == sizeof(buf) - 1) + pem = 1; + rewind(in); + return pem; +} + +/* Extract keyid from SKID of the cert. No return on error. */ +static unsigned long int extract_keyid(const char *certfile) +{ + uint32_t keyid_raw; + const ASN1_OCTET_STRING *skid; + int skid_len; + X509 *x = NULL; + int pem; + FILE *in; + + if (!(in = fopen(certfile, "r"))) { + log_err("Cannot open cert file %s: %s\n", certfile, + strerror(errno)); + exit(1); + } + if ((pem = is_encoding_pem(in))) + x = PEM_read_X509(in, &x, NULL, NULL); + else + x = d2i_X509_fp(in, &x); + if (!x) { + ERR_print_errors_fp(stderr); + log_err("Cannot read x509 cert from %s file %s\n", + pem? "PEM" : "DER", certfile); + fclose(in); + exit(1); + } + fclose(in); + + if (!(skid = X509_get0_subject_key_id(x))) { + log_err("%s: SKID not found\n", certfile); + goto err_free; + } + skid_len = ASN1_STRING_length(skid); + if (skid_len < sizeof(keyid_raw)) { + log_err("%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)); + log_info("keyid %04x (from %s)\n", ntohl(keyid_raw), certfile); + return ntohl(keyid_raw); + +err_free: + X509_free(x); + exit(1); +} + int main(int argc, char *argv[]) { int err = 0, c, lind; ENGINE *eng = NULL; unsigned long int keyid; - char *eptr; #if !(OPENSSL_VERSION_NUMBER < 0x10100000) OPENSSL_init_crypto( @@ -2718,10 +2781,19 @@ 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 > UINT_MAX || keyid == 0) { + if (optarg[0] == '@') { + keyid = extract_keyid(optarg + 1); + } 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 > UINT_MAX || keyid == 0) { log_err("Invalid keyid value.\n"); exit(1); } 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 Tue May 4 04:33:57 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vitaly Chikunov X-Patchwork-Id: 12237337 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,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 5BBD9C433ED for ; Tue, 4 May 2021 04:35:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1BC73611AD for ; Tue, 4 May 2021 04:35:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229742AbhEDEgK (ORCPT ); Tue, 4 May 2021 00:36:10 -0400 Received: from vmicros1.altlinux.org ([194.107.17.57]:35652 "EHLO vmicros1.altlinux.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229715AbhEDEgK (ORCPT ); Tue, 4 May 2021 00:36:10 -0400 Received: from imap.altlinux.org (imap.altlinux.org [194.107.17.38]) by vmicros1.altlinux.org (Postfix) with ESMTP id 4067F72C8BA; Tue, 4 May 2021 07:35:15 +0300 (MSK) Received: from beacon.altlinux.org (unknown [193.43.10.250]) by imap.altlinux.org (Postfix) with ESMTPSA id 24D404A46E8; Tue, 4 May 2021 07:35:15 +0300 (MSK) From: Vitaly Chikunov To: Mimi Zohar , Dmitry Kasatkin , linux-integrity@vger.kernel.org Cc: Elvira Khabirova Subject: [PATCH v2 3/3] ima-evm-utils: Read keyid from the cert appended to the key file Date: Tue, 4 May 2021 07:33:57 +0300 Message-Id: <20210504043357.4093409-4-vt@altlinux.org> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20210504043357.4093409-1-vt@altlinux.org> References: <20210504043357.4093409-1-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 | 2 ++ src/libimaevm.c | 50 +++++++++++++++++++++++++++++++++++++++++++++++--- 2 files changed, 49 insertions(+), 3 deletions(-) diff --git a/README b/README index 0e1f6ba..2c21ba6 100644 --- a/README +++ b/README @@ -127,6 +127,8 @@ 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 481d29d..3607a76 100644 --- a/src/libimaevm.c +++ b/src/libimaevm.c @@ -57,6 +57,7 @@ #include #include #include +#include #include #include "imaevm.h" @@ -748,6 +749,47 @@ void calc_keyid_v2(uint32_t *keyid, char *str, EVP_PKEY *pkey) X509_PUBKEY_free(pk); } +/* Try to read keyid from key file (in case it have appended cert). */ +static int read_keyid(const char *keyfile, uint32_t *keyid) +{ + int skid_len; + const ASN1_OCTET_STRING *skid; + X509 *x = NULL; + FILE *fp; + + fp = fopen(keyfile, "r"); + if (!fp) { + log_err("Failed to open keyfile: %s\n", keyfile); + return 0; + } + if (!PEM_read_X509(fp, &x, NULL, NULL)) { + long error = ERR_GET_REASON(ERR_peek_last_error()); + + if (error == PEM_R_NO_START_LINE) { + log_debug("No cert in keyfile %s\n", keyfile); + ERR_clear_error(); + } else { + log_err("Error reading cert from keyfile %s: %s\n", + keyfile, ERR_reason_error_string(error)); + } + fclose(fp); + return 0; + } + fclose(fp); + if (!(skid = X509_get0_subject_key_id(x))) + return 0; + skid_len = ASN1_STRING_length(skid); + if (skid_len < sizeof(keyid)) + return 0; + /* keyid is the last 4 bytes of SKID. */ + memcpy(keyid, ASN1_STRING_get0_data(skid) + skid_len - sizeof(*keyid), + sizeof(*keyid)); + log_debug("keyid: "); + log_debug_dump(keyid, 4); + return 1; + +} + static EVP_PKEY *read_priv_pkey(const char *keyfile, const char *keypass) { FILE *fp; @@ -932,10 +974,12 @@ 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 (!read_keyid(keyfile, &hdr->keyid)) + calc_keyid_v2(&hdr->keyid, name, pkey); + } st = "EVP_PKEY_CTX_new"; if (!(ctx = EVP_PKEY_CTX_new(pkey, NULL)))