From patchwork Tue Apr 25 17:35:54 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 13223622 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 F0FEAC6FD18 for ; Tue, 25 Apr 2023 17:38:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234678AbjDYRis (ORCPT ); Tue, 25 Apr 2023 13:38:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41440 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234621AbjDYRir (ORCPT ); Tue, 25 Apr 2023 13:38:47 -0400 Received: from frasgout13.his.huawei.com (frasgout13.his.huawei.com [14.137.139.46]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1C5A2CC2E; Tue, 25 Apr 2023 10:38:28 -0700 (PDT) Received: from mail02.huawei.com (unknown [172.18.147.228]) by frasgout13.his.huawei.com (SkyGuard) with ESMTP id 4Q5TW52wVDz9xFHM; Wed, 26 Apr 2023 01:28:49 +0800 (CST) Received: from huaweicloud.com (unknown [10.204.63.22]) by APP1 (Coremail) with SMTP id LxC2BwD3dADLD0hkGxlWAg--.5466S5; Tue, 25 Apr 2023 18:38:04 +0100 (CET) From: Roberto Sassu To: dhowells@redhat.com, dwmw2@infradead.org, herbert@gondor.apana.org.au, davem@davemloft.net, jarkko@kernel.org, ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, martin.lau@linux.dev, song@kernel.org, yhs@fb.com, john.fastabend@gmail.com, kpsingh@kernel.org, sdf@google.com, haoluo@google.com, jolsa@kernel.org, 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, Roberto Sassu Subject: [RFC][PATCH 3/6] verification: Introduce verify_umd_signature() and verify_umd_message_sig() Date: Tue, 25 Apr 2023 19:35:54 +0200 Message-Id: <20230425173557.724688-4-roberto.sassu@huaweicloud.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230425173557.724688-1-roberto.sassu@huaweicloud.com> References: <20230425173557.724688-1-roberto.sassu@huaweicloud.com> MIME-Version: 1.0 X-CM-TRANSID: LxC2BwD3dADLD0hkGxlWAg--.5466S5 X-Coremail-Antispam: 1UD129KBjvJXoW3Gr4fKr18ZF18XFW3ZryDAwb_yoWxtrWfpF nY9r1FvFy3Jwn7AasxKa17Zw4fWrn5J347G3sFy3WxXFn7J3ZrKrs0gF4Y9rW5C34UJryY 9rZFqFy3Wwn8Aw7anT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUPqb4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUWw A2048vs2IY020Ec7CjxVAFwI0_Xr0E3s1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0rcxS w2x7M28EF7xvwVC0I7IYx2IY67AKxVW8JVW5JwA2z4x0Y4vE2Ix0cI8IcVCY1x0267AKxV W8Jr0_Cr1UM28EF7xvwVC2z280aVAFwI0_Gr0_Cr1l84ACjcxK6I8E87Iv6xkF7I0E14v2 6r4UJVWxJr1le2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xvF2IEw4CE5I8CrVC2j2 WlYx0E2Ix0cI8IcVAFwI0_Jrv_JF1lYx0Ex4A2jsIE14v26r1j6r4UMcvjeVCFs4IE7xkE bVWUJVW8JwACjcxG0xvY0x0EwIxGrwACI402YVCY1x02628vn2kIc2xKxwCY1x0262kKe7 AKxVW8ZVWrXwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02 F40E14v26r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_GFv_Wr ylIxkGc2Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVW8JVW5JwCI42IY6xIIjxv20xvEc7Cj xVAFwI0_Gr1j6F4UJwCI42IY6xAIw20EY4v20xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI 0_Gr0_Cr1lIxAIcVC2z280aVCY1x0267AKxVW8Jr0_Cr1UYxBIdaVFxhVjvjDU0xZFpf9x 07j4T5LUUUUU= X-CM-SenderInfo: purev21wro2thvvxqx5xdzvxpfor3voofrz/1tbiAgASBF1jj4iAGAAAs1 X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-State: RFC From: Roberto Sassu Introduce verify_umd_signature() and verify_umd_message_sig(), to verify UMD-parsed 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 | 48 ++++++++++++++ 2 files changed, 173 insertions(+) diff --git a/certs/system_keyring.c b/certs/system_keyring.c index a7a49b17ceb..d4c0de4dceb 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_UMD_SIG_PARSER +/** + * verify_umd_message_sig - Verify a UMD-parsed signature on system data. + * @data: The data to be verified (must be provided) + * @len: Size of @data + * @umd_sig: The UMD-parsed signature + * @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 UMD-parsed 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_umd_message_sig(const void *data, size_t len, + struct umd_sig_message *umd_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 && umd_sig_supply_detached_data(umd_sig, data, len)) { + pr_err("Failed to supply data for UMD-parsed 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 = umd_sig_verify_message(umd_sig, trusted_keys); + if (ret < 0) + goto error; + + if (view_content) { + size_t sig_data_len; + + ret = umd_sig_get_content_data(umd_sig, &data, &len, + &sig_data_len); + if (ret < 0) { + if (ret == -ENODATA) + pr_devel("UMD-parsed 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_umd_message_sig); + +/** + * verify_umd_signature - Verify a UMD-parsed signature on system data. + * @data: The data to be verified (must be provided) + * @len: Size of @data + * @raw_umd_sig: The raw signature to be parsed with UMD + * @raw_umd_sig_len: The size of @raw_umd_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 UMD-parsed 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_umd_signature(const void *data, size_t len, + const void *raw_umd_sig, size_t raw_umd_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 umd_sig_message *umd_sig; + int ret; + + umd_sig = umd_sig_parse_message(raw_umd_sig, raw_umd_sig_len); + if (IS_ERR(umd_sig)) + return PTR_ERR(umd_sig); + + ret = verify_umd_message_sig(data, len, umd_sig, trusted_keys, usage, + view_content, ctx); + + umd_sig_free_message(umd_sig); + pr_devel("<==%s() = %d\n", __func__, ret); + return ret; +} +EXPORT_SYMBOL_GPL(verify_umd_signature); +#endif /* CONFIG_UMD_SIG_PARSER */ #endif /* CONFIG_SYSTEM_DATA_VERIFICATION */ #ifdef CONFIG_INTEGRITY_PLATFORM_KEYRING diff --git a/include/linux/verification.h b/include/linux/verification.h index f34e50ebcf6..2e44ea17f23 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 umd_sig_message; extern int verify_pkcs7_signature(const void *data, size_t len, const void *raw_pkcs7, size_t pkcs7_len, @@ -62,6 +63,53 @@ extern int verify_pkcs7_message_sig(const void *data, size_t len, size_t asn1hdrlen), void *ctx); +#ifdef CONFIG_UMD_SIG_PARSER +extern int verify_umd_message_sig(const void *data, size_t len, + struct umd_sig_message *umd_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_umd_signature(const void *data, size_t len, + const void *raw_pgp, size_t pgp_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_umd_message_sig(const void *data, size_t len, + struct umd_sig_message *umd_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_umd_signature(const void *data, size_t len, + const void *raw_umd_sig, + size_t raw_umd_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_UMD_SIG_PARSER */ + #ifdef CONFIG_SIGNED_PE_FILE_VERIFICATION extern int verify_pefile_signature(const void *pebuf, unsigned pelen, struct key *trusted_keys,