From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id C35D62D8364; Thu, 11 Dec 2025 02:13:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=13.77.154.182 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765419194; cv=none; b=qXXVqKjmMo9QDkcxQErCpQOPs9+HJkMsEgnDl4MKQyzkBi9DPY/klrNoQKQwqt6I64kVUbVsoZF2OddzAs6hD7c8CaHc0Jc+Vuhc3FGTFUYOSFSR4Y3DTxHcoDpaBIsO9szNr1V6/7QQzgOWo4nKTOdAkjntgBx/Avm/2sDoTJU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765419194; c=relaxed/simple; bh=JdRHlwoj2ekW+YizjrNg1K6XKl5v6vm6K00XxhLHug0=; h=From:To:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=NDGVnzucxBJbttCdf9AyRM41Df+O3xjQqptlTJoa5ATz2DU3ZzUjohOhIvXjWxzE+9Er84t75ubQ+ly4YpYi7TIb9t0FFY0NRm/yYfGJR0O8/q5+VOwIqdhFsrT6mzCYMTm4GmLUrRn5XrUxlP0lEa8m4jtuH4Fg0X74AHuLlYw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com; spf=pass smtp.mailfrom=linux.microsoft.com; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b=lInPFTOn; arc=none smtp.client-ip=13.77.154.182 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b="lInPFTOn" Received: from narnia.corp.microsoft.com (unknown [40.78.12.133]) by linux.microsoft.com (Postfix) with ESMTPSA id 7E9742116043; Wed, 10 Dec 2025 18:13:10 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 7E9742116043 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1765419191; bh=+cUv2YDEFdHJCABGsGpyw43sJvYTINrg6wV3aMZO9tA=; h=From:To:Subject:Date:In-Reply-To:References:From; b=lInPFTOn4wx3xXJvPmVHSA+UW+dfQ8jMkTogn8fpkrSKOKbgyaEiWFeYjLofv1lIW uoR1wD28HDfE90fhOQSVcOmDkj8o55b37kTLPoaJwjy65DwQ5aBLtfdtZGCkGpRs1k 61IajokQEKz1bL9VS82K3CJrOWKzIXzd87QtY+y8= From: Blaise Boscaccy To: Blaise Boscaccy , Jonathan Corbet , Paul Moore , James Morris , "Serge E. Hallyn" , =?UTF-8?q?Micka=C3=ABl=20Sala=C3=BCn?= , =?UTF-8?q?G=C3=BCnther=20Noack?= , "Dr. David Alan Gilbert" , Andrew Morton , James.Bottomley@HansenPartnership.com, dhowells@redhat.com, linux-security-module@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, bpf@vger.kernel.org Subject: [RFC 03/11] certs: break out pkcs7 check into its own function Date: Wed, 10 Dec 2025 18:11:58 -0800 Message-ID: <20251211021257.1208712-4-bboscaccy@linux.microsoft.com> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20251211021257.1208712-1-bboscaccy@linux.microsoft.com> References: <20251211021257.1208712-1-bboscaccy@linux.microsoft.com> Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: James Bottomley Add new validate_pkcs7_trust() function which can operate on the system keyrings and is simply some of the innards of verify_pkcs7_message_sig(). Signed-off-by: James Bottomley --- certs/system_keyring.c | 76 +++++++++++++++++++++--------------- include/linux/verification.h | 2 + 2 files changed, 47 insertions(+), 31 deletions(-) diff --git a/certs/system_keyring.c b/certs/system_keyring.c index 9de610bf1f4b2..807ab4a6fc7ea 100644 --- a/certs/system_keyring.c +++ b/certs/system_keyring.c @@ -298,42 +298,19 @@ late_initcall(load_system_certificate_list); #ifdef CONFIG_SYSTEM_DATA_VERIFICATION /** - * verify_pkcs7_message_sig - Verify a PKCS#7-based signature on system data. - * @data: The data to be verified (NULL if expecting internal data). - * @len: Size of @data. + * validate_pkcs7_trust - add trust markers based on keyring * @pkcs7: The PKCS#7 message that is the signature. * @trusted_keys: Trusted keys to use (NULL for builtin trusted keys only, * (void *)1UL for all trusted keys). - * @usage: The use to which the key is being put. - * @view_content: Callback to gain access to content. - * @ctx: Context for callback. */ -int verify_pkcs7_message_sig(const void *data, size_t len, - struct pkcs7_message *pkcs7, - struct key *trusted_keys, - enum key_being_used_for usage, - int (*view_content)(void *ctx, - const void *data, size_t len, - size_t asn1hdrlen), - void *ctx) +int validate_pkcs7_trust(struct pkcs7_message *pkcs7, struct key *trusted_keys) { int ret; - /* The data should be detached - so we need to supply it. */ - if (data && pkcs7_supply_detached_data(pkcs7, data, len) < 0) { - pr_err("PKCS#7 signature with non-detached data\n"); - ret = -EBADMSG; - goto error; - } - - ret = pkcs7_verify(pkcs7, usage); - if (ret < 0) - goto error; - ret = is_key_on_revocation_list(pkcs7); if (ret != -ENOKEY) { pr_devel("PKCS#7 key is on revocation list\n"); - goto error; + return ret; } if (!trusted_keys) { @@ -351,18 +328,55 @@ int verify_pkcs7_message_sig(const void *data, size_t len, trusted_keys = NULL; #endif if (!trusted_keys) { - ret = -ENOKEY; pr_devel("PKCS#7 platform keyring is not available\n"); - goto error; + return -ENOKEY; } } ret = pkcs7_validate_trust(pkcs7, trusted_keys); - if (ret < 0) { - if (ret == -ENOKEY) - pr_devel("PKCS#7 signature not signed with a trusted key\n"); + if (ret == -ENOKEY) + pr_devel("PKCS#7 signature not signed with a trusted key\n"); + + return ret; +} +EXPORT_SYMBOL_GPL(validate_pkcs7_trust); + +/** + * verify_pkcs7_message_sig - Verify a PKCS#7-based signature on system data. + * @data: The data to be verified (NULL if expecting internal data). + * @len: Size of @data. + * @pkcs7: The PKCS#7 message that is the signature. + * @trusted_keys: Trusted keys to use (NULL for builtin trusted keys only, + * (void *)1UL for all trusted keys). + * @usage: The use to which the key is being put. + * @view_content: Callback to gain access to content. + * @ctx: Context for callback. + */ +int verify_pkcs7_message_sig(const void *data, size_t len, + struct pkcs7_message *pkcs7, + struct key *trusted_keys, + enum key_being_used_for usage, + int (*view_content)(void *ctx, + const void *data, size_t len, + size_t asn1hdrlen), + void *ctx) +{ + int ret; + + /* The data should be detached - so we need to supply it. */ + if (data && pkcs7_supply_detached_data(pkcs7, data, len) < 0) { + pr_err("PKCS#7 signature with non-detached data\n"); + ret = -EBADMSG; goto error; } + ret = pkcs7_verify(pkcs7, usage); + if (ret < 0) + goto error; + + ret = validate_pkcs7_trust(pkcs7, trusted_keys); + if (ret < 0) + goto error; + if (view_content) { size_t asn1hdrlen; diff --git a/include/linux/verification.h b/include/linux/verification.h index dec7f2beabfd4..57f1460d36f13 100644 --- a/include/linux/verification.h +++ b/include/linux/verification.h @@ -44,6 +44,8 @@ enum key_being_used_for { struct key; struct pkcs7_message; +extern int validate_pkcs7_trust(struct pkcs7_message *pkcs7, + struct key *trusted_keys); extern int verify_pkcs7_signature(const void *data, size_t len, const void *raw_pkcs7, size_t pkcs7_len, struct key *trusted_keys, -- 2.52.0