From patchwork Thu Jul 20 15:32:42 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 13320681 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D91BDEB64DA for ; Thu, 20 Jul 2023 15:36:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232766AbjGTPgM (ORCPT ); Thu, 20 Jul 2023 11:36:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41536 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232743AbjGTPfy (ORCPT ); Thu, 20 Jul 2023 11:35:54 -0400 Received: from frasgout11.his.huawei.com (unknown [14.137.139.23]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8D58E272B; Thu, 20 Jul 2023 08:35:37 -0700 (PDT) Received: from mail02.huawei.com (unknown [172.18.147.228]) by frasgout11.his.huawei.com (SkyGuard) with ESMTP id 4R6Ggm1jDQz9v7g2; Thu, 20 Jul 2023 23:24:20 +0800 (CST) Received: from huaweicloud.com (unknown [10.204.63.22]) by APP1 (Coremail) with SMTP id LxC2BwBHquXFU7lkGHDRBA--.21759S8; Thu, 20 Jul 2023 16:34:58 +0100 (CET) From: Roberto Sassu To: dhowells@redhat.com, dwmw2@infradead.org, herbert@gondor.apana.org.au, davem@davemloft.net, jarkko@kernel.org, zohar@linux.ibm.com, dmitry.kasatkin@gmail.com, paul@paul-moore.com, jmorris@namei.org, serge@hallyn.com Cc: linux-kernel@vger.kernel.org, keyrings@vger.kernel.org, linux-crypto@vger.kernel.org, linux-integrity@vger.kernel.org, linux-security-module@vger.kernel.org, pbrobinson@gmail.com, zbyszek@in.waw.pl, wiktor@metacode.biz, devel@lists.sequoia-pgp.org, gnupg-devel@gnupg.org, ebiggers@kernel.org, Jason@zx2c4.com, mail@maciej.szmigiero.name, antony@vennard.ch, konstantin@linuxfoundation.org, James.Bottomley@HansenPartnership.com, Roberto Sassu Subject: [RFC][PATCH v3 6/9] verification: Add verify_uasym_signature() and verify_uasym_sig_message() Date: Thu, 20 Jul 2023 17:32:42 +0200 Message-Id: <20230720153247.3755856-7-roberto.sassu@huaweicloud.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230720153247.3755856-1-roberto.sassu@huaweicloud.com> References: <20230720153247.3755856-1-roberto.sassu@huaweicloud.com> MIME-Version: 1.0 X-CM-TRANSID: LxC2BwBHquXFU7lkGHDRBA--.21759S8 X-Coremail-Antispam: 1UD129KBjvJXoW3JFy8CrW3Wr1rurykAF43ZFb_yoWxKF4xpF 9Yqr1rZF98Awn3Aa47Ka1I9w1fWrn5Jw17KasFy3WfZFnYq3ZrGrs0gF1YqrW5C348GFWj 9r9FvFW3KanxAw7anT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUBvb4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUAV Cq3wA2048vs2IY020Ec7CjxVAFwI0_Xr0E3s1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0 rcxSw2x7M28EF7xvwVC0I7IYx2IY67AKxVWUCVW8JwA2z4x0Y4vE2Ix0cI8IcVCY1x0267 AKxVW8Jr0_Cr1UM28EF7xvwVC2z280aVAFwI0_Gr0_Cr1l84ACjcxK6I8E87Iv6xkF7I0E 14v26r4UJVWxJr1le2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xvF2IEw4CE5I8CrV C2j2WlYx0E2Ix0cI8IcVAFwI0_Jr0_Jr4lYx0Ex4A2jsIE14v26r1j6r4UMcvjeVCFs4IE 7xkEbVWUJVW8JwACjcxG0xvY0x0EwIxGrwACI402YVCY1x02628vn2kIc2xKxwCF04k20x vY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I 3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_GFv_WrylIxkGc2Ij64vIr41lIx AIcVC0I7IYx2IY67AKxVWUCVW8JwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F4UJwCI 42IY6xAIw20EY4v20xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI0_Gr0_Cr1lIxAIcVC2z2 80aVCY1x0267AKxVW8Jr0_Cr1UYxBIdaVFxhVjvjDU0xZFpf9x07UZo7tUUUUU= X-CM-SenderInfo: purev21wro2thvvxqx5xdzvxpfor3voofrz/1tbiAQAEBF1jj5C8oAAAs8 X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org From: Roberto Sassu Introduce verify_uasym_signature() and verify_uasym_sig_message(), to verify user asymmetric key signatures from detached data. It aims to be used by kernel subsystems wishing to verify the authenticity of system data, with system-defined keyrings as trust anchor. Signed-off-by: Roberto Sassu --- certs/system_keyring.c | 125 +++++++++++++++++++++++++++++++++++ include/linux/verification.h | 46 +++++++++++++ 2 files changed, 171 insertions(+) diff --git a/certs/system_keyring.c b/certs/system_keyring.c index a7a49b17ceb..dbee2e5b732 100644 --- a/certs/system_keyring.c +++ b/certs/system_keyring.c @@ -16,6 +16,7 @@ #include #include #include +#include static struct key *builtin_trusted_keys; #ifdef CONFIG_SECONDARY_TRUSTED_KEYRING @@ -339,6 +340,130 @@ int verify_pkcs7_signature(const void *data, size_t len, } EXPORT_SYMBOL_GPL(verify_pkcs7_signature); +#ifdef CONFIG_UASYM_KEYS_SIGS +/** + * verify_uasym_sig_message - Verify a user asym key signature on system data + * @data: The data to be verified (must be provided) + * @len: Size of @data + * @uasym_sig: The signature context + * @trusted_keys: Trusted keys to use (NULL for builtin trusted keys only, + * (void *)1UL for all trusted keys) + * (void *)2UL for platform keys) + * @usage: The use to which the key is being put + * @view_content: Callback to gain access to content + * @ctx: Context for callback + * + * Verify the user asymmetric key signature of the supplied system data, + * against a key (if found) in the supplied trusted keyring. + * + * Return: Zero on successful verification, a negative value otherwise. + */ +int verify_uasym_sig_message(const void *data, size_t len, + struct uasym_sig_message *uasym_sig, + 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 && uasym_sig_supply_detached_data(uasym_sig, data, len)) { + pr_err("Failed to supply data for user asymmetric key signature\n"); + ret = -EBADMSG; + goto error; + } + + if (!trusted_keys) { + trusted_keys = builtin_trusted_keys; + } else if (trusted_keys == VERIFY_USE_SECONDARY_KEYRING) { +#ifdef CONFIG_SECONDARY_TRUSTED_KEYRING + trusted_keys = secondary_trusted_keys; +#else + trusted_keys = builtin_trusted_keys; +#endif + } else if (trusted_keys == VERIFY_USE_PLATFORM_KEYRING) { +#ifdef CONFIG_INTEGRITY_PLATFORM_KEYRING + trusted_keys = platform_trusted_keys; +#else + trusted_keys = NULL; +#endif + if (!trusted_keys) { + ret = -ENOKEY; + pr_devel("Platform keyring is not available\n"); + goto error; + } + } + + ret = uasym_sig_verify_message(uasym_sig, trusted_keys); + if (ret < 0) + goto error; + + if (view_content) { + size_t sig_data_len; + + ret = uasym_sig_get_content_data(uasym_sig, &data, &len, + &sig_data_len); + if (ret < 0) { + if (ret == -ENODATA) + pr_devel("User asymmetric key signature does not contain data\n"); + goto error; + } + + ret = view_content(ctx, data, len, sig_data_len); + kfree(data); + } +error: + pr_devel("<==%s() = %d\n", __func__, ret); + return ret; +} +EXPORT_SYMBOL_GPL(verify_uasym_sig_message); + +/** + * verify_uasym_signature - Verify a user asym key signature on system data + * @data: The data to be verified (must be provided) + * @len: Size of @data + * @raw_uasym_sig: The raw signature + * @raw_uasym_sig_len: The size of @raw_uasym_sig + * @trusted_keys: Trusted keys to use (NULL for builtin trusted keys only, + * (void *)1UL for all trusted keys) + * (void *)2UL for platform keys) + * @usage: The use to which the key is being put + * @view_content: Callback to gain access to content + * @ctx: Context for callback + * + * Verify the user asymmetric key signature of the supplied system data, + * against a key (if found) in the supplied trusted keyring. + * + * Return: Zero on successful verification, a negative value otherwise. + */ +int verify_uasym_signature(const void *data, size_t len, + const void *raw_uasym_sig, size_t raw_uasym_sig_len, + 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) +{ + struct uasym_sig_message *uasym_sig; + int ret; + + uasym_sig = uasym_sig_parse_message(raw_uasym_sig, raw_uasym_sig_len); + if (IS_ERR(uasym_sig)) + return PTR_ERR(uasym_sig); + + ret = verify_uasym_sig_message(data, len, uasym_sig, trusted_keys, usage, + view_content, ctx); + + uasym_sig_free_message(uasym_sig); + pr_devel("<==%s() = %d\n", __func__, ret); + return ret; +} +EXPORT_SYMBOL_GPL(verify_uasym_signature); +#endif /* CONFIG_UASYM_KEYS_SIGS */ #endif /* CONFIG_SYSTEM_DATA_VERIFICATION */ #ifdef CONFIG_INTEGRITY_PLATFORM_KEYRING diff --git a/include/linux/verification.h b/include/linux/verification.h index f34e50ebcf6..9e8deea7755 100644 --- a/include/linux/verification.h +++ b/include/linux/verification.h @@ -43,6 +43,7 @@ extern const char *const key_being_used_for[NR__KEY_BEING_USED_FOR]; struct key; struct pkcs7_message; +struct uasym_sig_message; extern int verify_pkcs7_signature(const void *data, size_t len, const void *raw_pkcs7, size_t pkcs7_len, @@ -62,6 +63,51 @@ extern int verify_pkcs7_message_sig(const void *data, size_t len, size_t asn1hdrlen), void *ctx); +#ifdef CONFIG_UASYM_KEYS_SIGS +int verify_uasym_sig_message(const void *data, size_t len, + struct uasym_sig_message *uasym_sig, + 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 verify_uasym_signature(const void *data, size_t len, + const void *raw_uasym_sig, + size_t raw_uasym_sig_len, + 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); +#else +static inline int verify_uasym_sig_message(const void *data, size_t len, + struct uasym_sig_message *uasym_sig, + 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) +{ + return -EOPNOTSUPP; +} + +static inline int verify_uasym_signature(const void *data, size_t len, + const void *raw_uasym_sig, + size_t raw_uasym_sig_len, + 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) +{ + return -EOPNOTSUPP; +} +#endif /* CONFIG_UASYM_KEYS_SIGS */ + #ifdef CONFIG_SIGNED_PE_FILE_VERIFICATION extern int verify_pefile_signature(const void *pebuf, unsigned pelen, struct key *trusted_keys,