From patchwork Tue Jan 11 18:03:15 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 12710323 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 EB5F7C433F5 for ; Tue, 11 Jan 2022 18:04:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345506AbiAKSEx (ORCPT ); Tue, 11 Jan 2022 13:04:53 -0500 Received: from frasgout.his.huawei.com ([185.176.79.56]:4401 "EHLO frasgout.his.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1349792AbiAKSEB (ORCPT ); Tue, 11 Jan 2022 13:04:01 -0500 Received: from fraeml714-chm.china.huawei.com (unknown [172.18.147.206]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4JYJPz0y9yz688jd; Wed, 12 Jan 2022 02:00:23 +0800 (CST) Received: from roberto-ThinkStation-P620.huawei.com (10.204.63.22) by fraeml714-chm.china.huawei.com (10.206.15.33) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.20; Tue, 11 Jan 2022 19:03:55 +0100 From: Roberto Sassu To: , , , CC: , , , , , , , Roberto Sassu Subject: [PATCH 11/14] verification: introduce verify_pgp_signature() Date: Tue, 11 Jan 2022 19:03:15 +0100 Message-ID: <20220111180318.591029-12-roberto.sassu@huawei.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220111180318.591029-1-roberto.sassu@huawei.com> References: <20220111180318.591029-1-roberto.sassu@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.204.63.22] X-ClientProxiedBy: lhreml754-chm.china.huawei.com (10.201.108.204) To fraeml714-chm.china.huawei.com (10.206.15.33) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: keyrings@vger.kernel.org Introduce verify_pgp_signature() to verify PGP signatures from detached data. It will be used by fsverity and by IMA. Signed-off-by: Roberto Sassu --- certs/system_keyring.c | 70 ++++++++++++++++++++++++++++++++++++ include/linux/verification.h | 23 ++++++++++++ 2 files changed, 93 insertions(+) diff --git a/certs/system_keyring.c b/certs/system_keyring.c index 692365dee2bd..26a11b1dcd59 100644 --- a/certs/system_keyring.c +++ b/certs/system_keyring.c @@ -16,6 +16,7 @@ #include #include #include +#include #include "common.h" static struct key *builtin_trusted_keys; @@ -289,6 +290,75 @@ int verify_pkcs7_signature(const void *data, size_t len, } EXPORT_SYMBOL_GPL(verify_pkcs7_signature); +#ifdef CONFIG_PGP_KEY_PARSER +/** + * verify_pgp_signature - Verify a PGP-based signature on system data. + * @data: The data to be verified (must be provided). + * @len: Size of @data. + * @raw_pgp: The PGP message that is the signature. + * @pgp_len: The size of @raw_pgp. + * @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_pgp_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) +{ + struct pgp_sig_verify *pgp_ctx; + int ret; + + if (!data || !len) + return -EINVAL; + + pgp_ctx = pgp_sig_parse(raw_pgp, pgp_len); + if (IS_ERR(pgp_ctx)) + return PTR_ERR(pgp_ctx); + + 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("PGP platform keyring is not available\n"); + goto error; + } + } + + /* The data should be detached - so we need to supply it. */ + if (pgp_sig_add_data(pgp_ctx, data, len)) { + pr_err("Failed to supply data for PGP signature\n"); + ret = -EBADMSG; + goto error; + } + + ret = pgp_sig_verify(pgp_ctx, trusted_keys); +error: + pgp_sig_verify_cancel(pgp_ctx, false); + pr_devel("<==%s() = %d\n", __func__, ret); + return ret; +} +EXPORT_SYMBOL_GPL(verify_pgp_signature); + +#endif /* CONFIG_PGP_KEY_PARSER */ #endif /* CONFIG_SYSTEM_DATA_VERIFICATION */ #ifdef CONFIG_INTEGRITY_PLATFORM_KEYRING diff --git a/include/linux/verification.h b/include/linux/verification.h index a655923335ae..c27516d68962 100644 --- a/include/linux/verification.h +++ b/include/linux/verification.h @@ -54,6 +54,29 @@ extern int verify_pkcs7_message_sig(const void *data, size_t len, size_t asn1hdrlen), void *ctx); +#ifdef CONFIG_PGP_KEY_PARSER +extern int verify_pgp_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_pgp_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) +{ + return -EOPNOTSUPP; +} +#endif /* CONFIG_PGP_KEY_PARSER */ + #ifdef CONFIG_SIGNED_PE_FILE_VERIFICATION extern int verify_pefile_signature(const void *pebuf, unsigned pelen, struct key *trusted_keys,