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[2604:1380:40f1:3f00::1]) by mx.google.com with ESMTPS id i71-20020a639d4a000000b005f059e58ea8si4218362pgd.466.2024.04.12.18.03.58 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 12 Apr 2024 18:03:58 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel+bounces-143482-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:40f1:3f00::1 as permitted sender) client-ip=2604:1380:40f1:3f00::1; Authentication-Results: mx.google.com; dkim=pass header.i=@linux.microsoft.com header.s=default header.b=fzT59qIb; arc=pass (i=1 spf=pass spfdomain=linux.microsoft.com dkim=pass dkdomain=linux.microsoft.com dmarc=pass fromdomain=linux.microsoft.com); spf=pass (google.com: domain of linux-kernel+bounces-143482-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:40f1:3f00::1 as permitted sender) smtp.mailfrom="linux-kernel+bounces-143482-linux.lists.archive=gmail.com@vger.kernel.org"; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linux.microsoft.com Received: from smtp.subspace.kernel.org (wormhole.subspace.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sy.mirrors.kernel.org (Postfix) with ESMTPS id 66542B22E3E for ; Sat, 13 Apr 2024 01:02:25 +0000 (UTC) Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 55FBD73196; Sat, 13 Apr 2024 00:56:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b="fzT59qIb" Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 3F85E18AED; Sat, 13 Apr 2024 00:56:09 +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=1712969776; cv=none; b=W530r3UCcR9SHvt6KX8e0+JzdePM/nLaTUZKZJTADMhuFl38DQ7m77hNMdrmetxkQgMy3gq+3G/uZOIXhZ23wLR6UQ25ZVRud7gK5U8xG7gX18BsaYyIojW5v75uUGGKXCbUgKYWseByTkIHi1quSZIkx77+az8pbbFh7Gng4WI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712969776; c=relaxed/simple; bh=Pa7KgSc2DGGxuA3N86+F8fQ8CJK4UEgojKkGdWTM05U=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References; b=ZO4I3RPAgldQLp3R7xZzuNdFZlHdHdF8bSzzvD05OFbfADSnMgBpmwfnCF9q65MHgF//MmRSnkhHDG/4+XN95pBo7KXTJEzVgflC+/cFwpUfw0a4uOaOv3ALYbUlfmgctcBVMSyhklLN7PXkFneMb+sLKNIM/khhg/xTetbmpJg= 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=fzT59qIb; 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 Received: by linux.microsoft.com (Postfix, from userid 1052) id 496EE20FC5EE; Fri, 12 Apr 2024 17:56:05 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 496EE20FC5EE DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1712969766; bh=BVwConVT+U5QEL/palka5IPZtAxmbk2wjprs5ZdRDTM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fzT59qIbSRTqTrRung91Y14FOiadnni0CpoROJldb25HgR99QrcDnqvRBbV2vK/6U j8s63QsoyHVuhnfy0CqvXJMoyySaSRVlnWfMvxPu1T69P1w1iZExUPBCNFWJc9H1MF q+CWeIPoJs9wQqPd/i9vJfmuZcOGrD6mDhSEN+48= From: Fan Wu To: corbet@lwn.net, zohar@linux.ibm.com, jmorris@namei.org, serge@hallyn.com, tytso@mit.edu, ebiggers@kernel.org, axboe@kernel.dk, agk@redhat.com, snitzer@kernel.org, eparis@redhat.com, paul@paul-moore.com Cc: linux-doc@vger.kernel.org, linux-integrity@vger.kernel.org, linux-security-module@vger.kernel.org, fsverity@lists.linux.dev, linux-block@vger.kernel.org, dm-devel@lists.linux.dev, audit@vger.kernel.org, linux-kernel@vger.kernel.org, Deven Bowers , Fan Wu Subject: [PATCH v17 14/21] ipe: add support for dm-verity as a trust provider Date: Fri, 12 Apr 2024 17:55:57 -0700 Message-Id: <1712969764-31039-15-git-send-email-wufan@linux.microsoft.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1712969764-31039-1-git-send-email-wufan@linux.microsoft.com> References: <1712969764-31039-1-git-send-email-wufan@linux.microsoft.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: From: Deven Bowers Allows author of IPE policy to indicate trust for a singular dm-verity volume, identified by roothash, through "dmverity_roothash" and all signed dm-verity volumes, through "dmverity_signature". Signed-off-by: Deven Bowers Signed-off-by: Fan Wu --- v2: + No Changes v3: + No changes v4: + No changes v5: + No changes v6: + Fix an improper cleanup that can result in a leak v7: + Squash patch 08/12, 10/12 to [11/16] v8: + Undo squash of 08/12, 10/12 - separating drivers/md/ from security/ & block/ + Use common-audit function for dmverity_signature. + Change implementation for storing the dm-verity digest to use the newly introduced dm_verity_digest structure introduced in patch 14/20. v9: + Adapt to the new parser v10: + Select the Kconfig when all dependencies are enabled v11: + No changes v12: + Refactor to use struct digest_info* instead of void* + Correct audit format v13: + Remove the CONFIG_IPE_PROP_DM_VERITY dependency inside the parser to make the policy grammar independent of the kernel config. v14: + No changes v15: + Fix one grammar issue in KCONFIG + Switch to use security_bdev_setintegrity() hook v16: + Refactor for enum integrity type v17: + Add years to license header + Fix code and documentation style issues + Return -EINVAL in ipe_bdev_setintegrity when passed type is not supported + Use new enum name LSM_INT_DMVERITY_SIG_VALID --- security/ipe/Kconfig | 18 ++++++ security/ipe/Makefile | 1 + security/ipe/audit.c | 29 ++++++++- security/ipe/digest.c | 118 +++++++++++++++++++++++++++++++++++ security/ipe/digest.h | 26 ++++++++ security/ipe/eval.c | 91 ++++++++++++++++++++++++++- security/ipe/eval.h | 10 +++ security/ipe/hooks.c | 78 +++++++++++++++++++++++ security/ipe/hooks.h | 8 +++ security/ipe/ipe.c | 15 +++++ security/ipe/ipe.h | 4 ++ security/ipe/policy.h | 3 + security/ipe/policy_parser.c | 24 ++++++- 13 files changed, 421 insertions(+), 4 deletions(-) create mode 100644 security/ipe/digest.c create mode 100644 security/ipe/digest.h diff --git a/security/ipe/Kconfig b/security/ipe/Kconfig index ac4d558e69d5..6179752c614f 100644 --- a/security/ipe/Kconfig +++ b/security/ipe/Kconfig @@ -8,6 +8,7 @@ menuconfig SECURITY_IPE depends on SECURITY && SECURITYFS && AUDIT && AUDITSYSCALL select PKCS7_MESSAGE_PARSER select SYSTEM_DATA_VERIFICATION + select IPE_PROP_DM_VERITY if DM_VERITY && DM_VERITY_VERIFY_ROOTHASH_SIG help This option enables the Integrity Policy Enforcement LSM allowing users to define a policy to enforce a trust-based access @@ -15,3 +16,20 @@ menuconfig SECURITY_IPE admins to reconfigure trust requirements on the fly. If unsure, answer N. + +if SECURITY_IPE +menu "IPE Trust Providers" + +config IPE_PROP_DM_VERITY + bool "Enable support for dm-verity volumes" + depends on DM_VERITY && DM_VERITY_VERIFY_ROOTHASH_SIG + help + This option enables the properties 'dmverity_signature' and + 'dmverity_roothash' in IPE policy. These properties evaluate + to TRUE when a file is evaluated against a dm-verity volume + that was mounted with a valid signed root-hash or the + volume's root hash matches the supplied value in the policy. + +endmenu + +endif diff --git a/security/ipe/Makefile b/security/ipe/Makefile index 62caccba14b4..e1019bb9f0f3 100644 --- a/security/ipe/Makefile +++ b/security/ipe/Makefile @@ -6,6 +6,7 @@ # obj-$(CONFIG_SECURITY_IPE) += \ + digest.o \ eval.o \ hooks.o \ fs.o \ diff --git a/security/ipe/audit.c b/security/ipe/audit.c index a416291ba477..2c98520267c1 100644 --- a/security/ipe/audit.c +++ b/security/ipe/audit.c @@ -13,6 +13,7 @@ #include "hooks.h" #include "policy.h" #include "audit.h" +#include "digest.h" #define ACTSTR(x) ((x) == IPE_ACTION_ALLOW ? "ALLOW" : "DENY") @@ -49,8 +50,22 @@ static const char *const audit_hook_names[__IPE_HOOK_MAX] = { static const char *const audit_prop_names[__IPE_PROP_MAX] = { "boot_verified=FALSE", "boot_verified=TRUE", + "dmverity_roothash=", + "dmverity_signature=FALSE", + "dmverity_signature=TRUE", }; +/** + * audit_dmv_roothash() - audit the roothash of a dmverity_roothash property. + * @ab: Supplies a pointer to the audit_buffer to append to. + * @rh: Supplies a pointer to the digest structure. + */ +static void audit_dmv_roothash(struct audit_buffer *ab, const void *rh) +{ + audit_log_format(ab, "%s", audit_prop_names[IPE_PROP_DMV_ROOTHASH]); + ipe_digest_audit(ab, rh); +} + /** * audit_rule() - audit an IPE policy rule. * @ab: Supplies a pointer to the audit_buffer to append to. @@ -62,8 +77,18 @@ static void audit_rule(struct audit_buffer *ab, const struct ipe_rule *r) audit_log_format(ab, " rule=\"%s ", audit_op_names[r->op]); - list_for_each_entry(ptr, &r->props, next) - audit_log_format(ab, "%s ", audit_prop_names[ptr->type]); + list_for_each_entry(ptr, &r->props, next) { + switch (ptr->type) { + case IPE_PROP_DMV_ROOTHASH: + audit_dmv_roothash(ab, ptr->value); + break; + default: + audit_log_format(ab, "%s", audit_prop_names[ptr->type]); + break; + } + + audit_log_format(ab, " "); + } audit_log_format(ab, "action=%s\"", ACTSTR(r->action)); } diff --git a/security/ipe/digest.c b/security/ipe/digest.c new file mode 100644 index 000000000000..493716370570 --- /dev/null +++ b/security/ipe/digest.c @@ -0,0 +1,118 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2020-2024 Microsoft Corporation. All rights reserved. + */ + +#include "digest.h" + +/** + * ipe_digest_parse() - parse a digest in IPE's policy. + * @valstr: Supplies the string parsed from the policy. + * + * Digests in IPE are defined in a standard way: + * : + * + * Use this function to create a property to parse the digest + * consistently. The parsed digest will be saved in @value in IPE's + * policy. + * + * Return: The parsed digest_info structure on success. If an error occurs, + * the function will return the error value (via ERR_PTR). + */ +struct digest_info *ipe_digest_parse(const char *valstr) +{ + struct digest_info *info = NULL; + char *sep, *raw_digest; + size_t raw_digest_len; + u8 *digest = NULL; + char *alg = NULL; + int rc = 0; + + info = kzalloc(sizeof(*info), GFP_KERNEL); + if (!info) + return ERR_PTR(-ENOMEM); + + sep = strchr(valstr, ':'); + if (!sep) { + rc = -EBADMSG; + goto err; + } + + alg = kstrndup(valstr, sep - valstr, GFP_KERNEL); + if (!alg) { + rc = -ENOMEM; + goto err; + } + + raw_digest = sep + 1; + raw_digest_len = strlen(raw_digest); + + info->digest_len = (raw_digest_len + 1) / 2; + digest = kzalloc(info->digest_len, GFP_KERNEL); + if (!digest) { + rc = -ENOMEM; + goto err; + } + + rc = hex2bin(digest, raw_digest, info->digest_len); + if (rc < 0) { + rc = -EINVAL; + goto err; + } + + info->alg = alg; + info->digest = digest; + return info; + +err: + kfree(alg); + kfree(digest); + kfree(info); + return ERR_PTR(rc); +} + +/** + * ipe_digest_eval() - evaluate an IPE digest against another digest. + * @expected: Supplies the policy-provided digest value. + * @digest: Supplies the digest to compare against the policy digest value. + * + * Return: + * * %true - digests match + * * %false - digests do not match + */ +bool ipe_digest_eval(const struct digest_info *expected, + const struct digest_info *digest) +{ + return (expected->digest_len == digest->digest_len) && + (!strcmp(expected->alg, digest->alg)) && + (!memcmp(expected->digest, digest->digest, expected->digest_len)); +} + +/** + * ipe_digest_free() - free an IPE digest. + * @info: Supplies a pointer the policy-provided digest to free. + */ +void ipe_digest_free(struct digest_info *info) +{ + if (IS_ERR_OR_NULL(info)) + return; + + kfree(info->alg); + kfree(info->digest); + kfree(info); +} + +/** + * ipe_digest_audit() - audit a digest that was sourced from IPE's policy. + * @ab: Supplies the audit_buffer to append the formatted result. + * @info: Supplies a pointer to source the audit record from. + * + * Digests in IPE are audited in this format: + * : + */ +void ipe_digest_audit(struct audit_buffer *ab, const struct digest_info *info) +{ + audit_log_untrustedstring(ab, info->alg); + audit_log_format(ab, ":"); + audit_log_n_hex(ab, info->digest, info->digest_len); +} diff --git a/security/ipe/digest.h b/security/ipe/digest.h new file mode 100644 index 000000000000..52c9b3844a38 --- /dev/null +++ b/security/ipe/digest.h @@ -0,0 +1,26 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2020-2024 Microsoft Corporation. All rights reserved. + */ + +#ifndef _IPE_DIGEST_H +#define _IPE_DIGEST_H + +#include +#include + +#include "policy.h" + +struct digest_info { + const char *alg; + const u8 *digest; + size_t digest_len; +}; + +struct digest_info *ipe_digest_parse(const char *valstr); +void ipe_digest_free(struct digest_info *digest_info); +void ipe_digest_audit(struct audit_buffer *ab, const struct digest_info *val); +bool ipe_digest_eval(const struct digest_info *expected, + const struct digest_info *digest); + +#endif /* _IPE_DIGEST_H */ diff --git a/security/ipe/eval.c b/security/ipe/eval.c index dd9064974be6..477f0d0ffda8 100644 --- a/security/ipe/eval.c +++ b/security/ipe/eval.c @@ -15,10 +15,12 @@ #include "eval.h" #include "policy.h" #include "audit.h" +#include "digest.h" struct ipe_policy __rcu *ipe_active_policy; bool success_audit; bool enforce = true; +#define INO_BLOCK_DEV(ino) ((ino)->i_sb->s_bdev) #define FILE_SUPERBLOCK(f) ((f)->f_path.mnt->mnt_sb) @@ -32,6 +34,23 @@ static void build_ipe_sb_ctx(struct ipe_eval_ctx *ctx, const struct file *const ctx->initramfs = ipe_sb(FILE_SUPERBLOCK(file))->initramfs; } +#ifdef CONFIG_IPE_PROP_DM_VERITY +/** + * build_ipe_bdev_ctx() - Build ipe_bdev field of an evaluation context. + * @ctx: Supplies a pointer to the context to be populated. + * @ino: Supplies the inode struct of the file triggered IPE event. + */ +static void build_ipe_bdev_ctx(struct ipe_eval_ctx *ctx, const struct inode *const ino) +{ + if (INO_BLOCK_DEV(ino)) + ctx->ipe_bdev = ipe_bdev(INO_BLOCK_DEV(ino)); +} +#else +static void build_ipe_bdev_ctx(struct ipe_eval_ctx *ctx, const struct inode *const ino) +{ +} +#endif /* CONFIG_IPE_PROP_DM_VERITY */ + /** * ipe_build_eval_ctx() - Build an ipe evaluation context. * @ctx: Supplies a pointer to the context to be populated. @@ -48,8 +67,10 @@ void ipe_build_eval_ctx(struct ipe_eval_ctx *ctx, ctx->op = op; ctx->hook = hook; - if (file) + if (file) { build_ipe_sb_ctx(ctx, file); + build_ipe_bdev_ctx(ctx, d_real_inode(file->f_path.dentry)); + } } /** @@ -65,6 +86,68 @@ static bool evaluate_boot_verified(const struct ipe_eval_ctx *const ctx) return ctx->initramfs; } +#ifdef CONFIG_IPE_PROP_DM_VERITY +/** + * evaluate_dmv_roothash() - Evaluate @ctx against a dmv roothash property. + * @ctx: Supplies a pointer to the context being evaluated. + * @p: Supplies a pointer to the property being evaluated. + * + * Return: + * * %true - The current @ctx match the @p + * * %false - The current @ctx doesn't match the @p + */ +static bool evaluate_dmv_roothash(const struct ipe_eval_ctx *const ctx, + struct ipe_prop *p) +{ + return !!ctx->ipe_bdev && + !!ctx->ipe_bdev->root_hash && + ipe_digest_eval(p->value, + ctx->ipe_bdev->root_hash); +} + +/** + * evaluate_dmv_sig_false() - Evaluate @ctx against a dmv sig false property. + * @ctx: Supplies a pointer to the context being evaluated. + * + * Return: + * * %true - The current @ctx match the property + * * %false - The current @ctx doesn't match the property + */ +static bool evaluate_dmv_sig_false(const struct ipe_eval_ctx *const ctx) +{ + return !ctx->ipe_bdev || (!ctx->ipe_bdev->dm_verity_signed); +} + +/** + * evaluate_dmv_sig_true() - Evaluate @ctx against a dmv sig true property. + * @ctx: Supplies a pointer to the context being evaluated. + * + * Return: + * * %true - The current @ctx match the property + * * %false - The current @ctx doesn't match the property + */ +static bool evaluate_dmv_sig_true(const struct ipe_eval_ctx *const ctx) +{ + return !evaluate_dmv_sig_false(ctx); +} +#else +static bool evaluate_dmv_roothash(const struct ipe_eval_ctx *const ctx, + struct ipe_prop *p) +{ + return false; +} + +static bool evaluate_dmv_sig_false(const struct ipe_eval_ctx *const ctx) +{ + return false; +} + +static bool evaluate_dmv_sig_true(const struct ipe_eval_ctx *const ctx) +{ + return false; +} +#endif /* CONFIG_IPE_PROP_DM_VERITY */ + /** * evaluate_property() - Analyze @ctx against a rule property. * @ctx: Supplies a pointer to the context to be evaluated. @@ -85,6 +168,12 @@ static bool evaluate_property(const struct ipe_eval_ctx *const ctx, return !evaluate_boot_verified(ctx); case IPE_PROP_BOOT_VERIFIED_TRUE: return evaluate_boot_verified(ctx); + case IPE_PROP_DMV_ROOTHASH: + return evaluate_dmv_roothash(ctx, p); + case IPE_PROP_DMV_SIG_FALSE: + return evaluate_dmv_sig_false(ctx); + case IPE_PROP_DMV_SIG_TRUE: + return evaluate_dmv_sig_true(ctx); default: return false; } diff --git a/security/ipe/eval.h b/security/ipe/eval.h index 80b74f55fa69..aa29e8036c48 100644 --- a/security/ipe/eval.h +++ b/security/ipe/eval.h @@ -22,12 +22,22 @@ struct ipe_superblock { bool initramfs; }; +#ifdef CONFIG_IPE_PROP_DM_VERITY +struct ipe_bdev { + bool dm_verity_signed; + struct digest_info *root_hash; +}; +#endif /* CONFIG_IPE_PROP_DM_VERITY */ + struct ipe_eval_ctx { enum ipe_op_type op; enum ipe_hook_type hook; const struct file *file; bool initramfs; +#ifdef CONFIG_IPE_PROP_DM_VERITY + const struct ipe_bdev *ipe_bdev; +#endif /* CONFIG_IPE_PROP_DM_VERITY */ }; enum ipe_match { diff --git a/security/ipe/hooks.c b/security/ipe/hooks.c index b68719bf44fb..5d4a9abb9c44 100644 --- a/security/ipe/hooks.c +++ b/security/ipe/hooks.c @@ -8,10 +8,14 @@ #include #include #include +#include +#include +#include #include "ipe.h" #include "hooks.h" #include "eval.h" +#include "digest.h" /** * ipe_bprm_check_security() - ipe security hook function for bprm check. @@ -191,3 +195,77 @@ void ipe_unpack_initramfs(void) { ipe_sb(current->fs->root.mnt->mnt_sb)->initramfs = true; } + +#ifdef CONFIG_IPE_PROP_DM_VERITY +/** + * ipe_bdev_free_security() - Free IPE's LSM blob of block_devices. + * @bdev: Supplies a pointer to a block_device that contains the structure + * to free. + */ +void ipe_bdev_free_security(struct block_device *bdev) +{ + struct ipe_bdev *blob = ipe_bdev(bdev); + + ipe_digest_free(blob->root_hash); +} + +/** + * ipe_bdev_setintegrity() - Save integrity data from a bdev to IPE's LSM blob. + * @bdev: Supplies a pointer to a block_device that contains the LSM blob. + * @type: Supplies the integrity type. + * @value: Supplies the value to store. + * @size: The size of @value. + * + * This hook is currently used to save dm-verity's root hash or the existence + * of a validated signed dm-verity root hash into LSM blob. + * + * Return: %0 on success. If an error occurs, the function will return the + * -errno. + */ +int ipe_bdev_setintegrity(struct block_device *bdev, enum lsm_integrity_type type, + const void *value, size_t size) +{ + const struct dm_verity_digest *digest = NULL; + struct ipe_bdev *blob = ipe_bdev(bdev); + struct digest_info *info = NULL; + + if (type == LSM_INT_DMVERITY_ROOTHASH) { + if (!value) { + ipe_digest_free(blob->root_hash); + blob->root_hash = NULL; + + return 0; + } + digest = value; + + info = kzalloc(sizeof(*info), GFP_KERNEL); + if (!info) + return -ENOMEM; + + info->digest = kmemdup(digest->digest, digest->digest_len, + GFP_KERNEL); + if (!info->digest) + goto dmv_roothash_err; + + info->alg = kstrdup(digest->alg, GFP_KERNEL); + if (!info->alg) + goto dmv_roothash_err; + + info->digest_len = digest->digest_len; + + blob->root_hash = info; + + return 0; +dmv_roothash_err: + ipe_digest_free(info); + + return -ENOMEM; + } else if (type == LSM_INT_DMVERITY_SIG_VALID) { + blob->dm_verity_signed = size > 0 && value; + + return 0; + } + + return -EINVAL; +} +#endif /* CONFIG_IPE_PROP_DM_VERITY */ diff --git a/security/ipe/hooks.h b/security/ipe/hooks.h index f4f0b544ddcc..4d585fb6ada3 100644 --- a/security/ipe/hooks.h +++ b/security/ipe/hooks.h @@ -8,6 +8,7 @@ #include #include #include +#include enum ipe_hook_type { IPE_HOOK_BPRM_CHECK = 0, @@ -35,4 +36,11 @@ int ipe_kernel_load_data(enum kernel_load_data_id id, bool contents); void ipe_unpack_initramfs(void); +#ifdef CONFIG_IPE_PROP_DM_VERITY +void ipe_bdev_free_security(struct block_device *bdev); + +int ipe_bdev_setintegrity(struct block_device *bdev, enum lsm_integrity_type type, + const void *value, size_t len); +#endif /* CONFIG_IPE_PROP_DM_VERITY */ + #endif /* _IPE_HOOKS_H */ diff --git a/security/ipe/ipe.c b/security/ipe/ipe.c index 53f2196b9bcc..99cb42caa63a 100644 --- a/security/ipe/ipe.c +++ b/security/ipe/ipe.c @@ -7,11 +7,15 @@ #include "ipe.h" #include "eval.h" #include "hooks.h" +#include "eval.h" bool ipe_enabled; static struct lsm_blob_sizes ipe_blobs __ro_after_init = { .lbs_superblock = sizeof(struct ipe_superblock), +#ifdef CONFIG_IPE_PROP_DM_VERITY + .lbs_bdev = sizeof(struct ipe_bdev), +#endif /* CONFIG_IPE_PROP_DM_VERITY */ }; static const struct lsm_id ipe_lsmid = { @@ -24,6 +28,13 @@ struct ipe_superblock *ipe_sb(const struct super_block *sb) return sb->s_security + ipe_blobs.lbs_superblock; } +#ifdef CONFIG_IPE_PROP_DM_VERITY +struct ipe_bdev *ipe_bdev(struct block_device *b) +{ + return b->security + ipe_blobs.lbs_bdev; +} +#endif /* CONFIG_IPE_PROP_DM_VERITY */ + static struct security_hook_list ipe_hooks[] __ro_after_init = { LSM_HOOK_INIT(bprm_check_security, ipe_bprm_check_security), LSM_HOOK_INIT(mmap_file, ipe_mmap_file), @@ -31,6 +42,10 @@ static struct security_hook_list ipe_hooks[] __ro_after_init = { LSM_HOOK_INIT(kernel_read_file, ipe_kernel_read_file), LSM_HOOK_INIT(kernel_load_data, ipe_kernel_load_data), LSM_HOOK_INIT(initramfs_populated, ipe_unpack_initramfs), +#ifdef CONFIG_IPE_PROP_DM_VERITY + LSM_HOOK_INIT(bdev_free_security, ipe_bdev_free_security), + LSM_HOOK_INIT(bdev_setintegrity, ipe_bdev_setintegrity), +#endif /* CONFIG_IPE_PROP_DM_VERITY */ }; /** diff --git a/security/ipe/ipe.h b/security/ipe/ipe.h index 4aa18d1d0525..01f46286e383 100644 --- a/security/ipe/ipe.h +++ b/security/ipe/ipe.h @@ -16,4 +16,8 @@ struct ipe_superblock *ipe_sb(const struct super_block *sb); extern bool ipe_enabled; +#ifdef CONFIG_IPE_PROP_DM_VERITY +struct ipe_bdev *ipe_bdev(struct block_device *b); +#endif /* CONFIG_IPE_PROP_DM_VERITY */ + #endif /* _IPE_H */ diff --git a/security/ipe/policy.h b/security/ipe/policy.h index ffd60cc7fda6..26776092c710 100644 --- a/security/ipe/policy.h +++ b/security/ipe/policy.h @@ -33,6 +33,9 @@ enum ipe_action_type { enum ipe_prop_type { IPE_PROP_BOOT_VERIFIED_FALSE, IPE_PROP_BOOT_VERIFIED_TRUE, + IPE_PROP_DMV_ROOTHASH, + IPE_PROP_DMV_SIG_FALSE, + IPE_PROP_DMV_SIG_TRUE, __IPE_PROP_MAX }; diff --git a/security/ipe/policy_parser.c b/security/ipe/policy_parser.c index 84cc688be3a2..71c84b293029 100644 --- a/security/ipe/policy_parser.c +++ b/security/ipe/policy_parser.c @@ -11,6 +11,7 @@ #include "policy.h" #include "policy_parser.h" +#include "digest.h" #define START_COMMENT '#' #define IPE_POLICY_DELIM " \t" @@ -221,6 +222,7 @@ static void free_rule(struct ipe_rule *r) list_for_each_entry_safe(p, t, &r->props, next) { list_del(&p->next); + ipe_digest_free(p->value); kfree(p); } @@ -273,6 +275,9 @@ static enum ipe_action_type parse_action(char *t) static const match_table_t property_tokens = { {IPE_PROP_BOOT_VERIFIED_FALSE, "boot_verified=FALSE"}, {IPE_PROP_BOOT_VERIFIED_TRUE, "boot_verified=TRUE"}, + {IPE_PROP_DMV_ROOTHASH, "dmverity_roothash=%s"}, + {IPE_PROP_DMV_SIG_FALSE, "dmverity_signature=FALSE"}, + {IPE_PROP_DMV_SIG_TRUE, "dmverity_signature=TRUE"}, {IPE_PROP_INVALID, NULL} }; @@ -295,6 +300,7 @@ static int parse_property(char *t, struct ipe_rule *r) struct ipe_prop *p = NULL; int rc = 0; int token; + char *dup = NULL; p = kzalloc(sizeof(*p), GFP_KERNEL); if (!p) @@ -303,8 +309,22 @@ static int parse_property(char *t, struct ipe_rule *r) token = match_token(t, property_tokens, args); switch (token) { + case IPE_PROP_DMV_ROOTHASH: + dup = match_strdup(&args[0]); + if (!dup) { + rc = -ENOMEM; + goto err; + } + p->value = ipe_digest_parse(dup); + if (IS_ERR(p->value)) { + rc = PTR_ERR(p->value); + goto err; + } + fallthrough; case IPE_PROP_BOOT_VERIFIED_FALSE: case IPE_PROP_BOOT_VERIFIED_TRUE: + case IPE_PROP_DMV_SIG_FALSE: + case IPE_PROP_DMV_SIG_TRUE: p->type = token; break; default: @@ -315,10 +335,12 @@ static int parse_property(char *t, struct ipe_rule *r) goto err; list_add_tail(&p->next, &r->props); +out: + kfree(dup); return rc; err: kfree(p); - return rc; + goto out; } /** -- 2.44.0