From patchwork Thu Jul 6 14:42:19 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 13303867 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 1FE9DEB64D9 for ; Thu, 6 Jul 2023 14:47:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233490AbjGFOr0 (ORCPT ); Thu, 6 Jul 2023 10:47:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34784 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233270AbjGFOrB (ORCPT ); Thu, 6 Jul 2023 10:47:01 -0400 Received: from frasgout11.his.huawei.com (unknown [14.137.139.23]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 939291FD0; Thu, 6 Jul 2023 07:46:59 -0700 (PDT) Received: from mail02.huawei.com (unknown [172.18.147.227]) by frasgout11.his.huawei.com (SkyGuard) with ESMTP id 4QxfGN6k7Yz9v7VL; Thu, 6 Jul 2023 22:35:56 +0800 (CST) Received: from huaweicloud.com (unknown [10.204.63.22]) by APP1 (Coremail) with SMTP id LxC2BwAHQg0y06ZkPxkwBA--.58122S8; Thu, 06 Jul 2023 15:46:14 +0100 (CET) From: Roberto Sassu To: dhowells@redhat.com, dwmw2@infradead.org, herbert@gondor.apana.org.au, davem@davemloft.net, jarkko@kernel.org, song@kernel.org, jolsa@kernel.org, ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, martin.lau@linux.dev, yhs@fb.com, john.fastabend@gmail.com, kpsingh@kernel.org, sdf@google.com, haoluo@google.com, rostedt@goodmis.org, mhiramat@kernel.org, mykolal@fb.com, shuah@kernel.org Cc: linux-kernel@vger.kernel.org, keyrings@vger.kernel.org, linux-crypto@vger.kernel.org, bpf@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, pbrobinson@gmail.com, zbyszek@in.waw.pl, zohar@linux.ibm.com, linux-integrity@vger.kernel.org, paul@paul-moore.com, linux-security-module@vger.kernel.org, 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 06/10] verification: Add verify_uasym_signature() and verify_uasym_sig_message() Date: Thu, 6 Jul 2023 16:42:19 +0200 Message-Id: <20230706144225.1046544-7-roberto.sassu@huaweicloud.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230706144225.1046544-1-roberto.sassu@huaweicloud.com> References: <20230706144225.1046544-1-roberto.sassu@huaweicloud.com> MIME-Version: 1.0 X-CM-TRANSID: LxC2BwAHQg0y06ZkPxkwBA--.58122S8 X-Coremail-Antispam: 1UD129KBjvJXoW3JFy8CrW3Wr1rurykAF43ZFb_yoWxKFW5pF 9Yqr1rZF98Awn3Aa47Ka1I9w1fWrn5Jw17KasFy3WfZF1vq3ZrGrs0gF1YqrW5C348GFWY 9rZFvFW3KanxAw7anT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUPlb4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUAV Cq3wA2048vs2IY020Ec7CjxVAFwI0_Xr0E3s1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0 rcxSw2x7M28EF7xvwVC0I7IYx2IY67AKxVWUCVW8JwA2z4x0Y4vE2Ix0cI8IcVCY1x0267 AKxVW8Jr0_Cr1UM28EF7xvwVC2z280aVAFwI0_Cr0_Gr1UM28EF7xvwVC2z280aVCY1x02 67AKxVWxJr0_GcWle2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xvF2IEw4CE5I8CrV C2j2WlYx0E2Ix0cI8IcVAFwI0_Jr0_Jr4lYx0Ex4A2jsIE14v26r1j6r4UMcvjeVCFs4IE 7xkEbVWUJVW8JwACjcxG0xvY0x0EwIxGrwACI402YVCY1x02628vn2kIc2xKxwCY1x0262 kKe7AKxVW8ZVWrXwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s02 6c02F40E14v26r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_Wr v_Gr1UMIIYrxkI7VAKI48JMIIF0xvE2Ix0cI8IcVAFwI0_JFI_Gr1lIxAIcVC0I7IYx2IY 6xkF7I0E14v26r4UJVWxJr1lIxAIcVCF04k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2js IE14v26r4j6F4UMIIF0xvEx4A2jsIEc7CjxVAFwI0_Cr1j6rxdYxBIdaVFxhVjvjDU0xZF pf9x07jIPfQUUUUU= X-CM-SenderInfo: purev21wro2thvvxqx5xdzvxpfor3voofrz/1tbiAgAKBF1jj4vZ7gAAsB 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 | 50 ++++++++++++++ 2 files changed, 175 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..818f0ca4e12 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 +63,55 @@ extern int verify_pkcs7_message_sig(const void *data, size_t len, size_t asn1hdrlen), void *ctx); +#ifdef CONFIG_UASYM_KEYS_SIGS +extern 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); +extern 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,