From patchwork Tue Oct 10 20:40:41 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Josef Bacik X-Patchwork-Id: 13416123 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 184B1CD6115 for ; Tue, 10 Oct 2023 20:42:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234483AbjJJUl5 (ORCPT ); Tue, 10 Oct 2023 16:41:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45904 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234726AbjJJUli (ORCPT ); Tue, 10 Oct 2023 16:41:38 -0400 Received: from mail-yw1-x1130.google.com (mail-yw1-x1130.google.com [IPv6:2607:f8b0:4864:20::1130]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 51F1EB8 for ; Tue, 10 Oct 2023 13:41:34 -0700 (PDT) Received: by mail-yw1-x1130.google.com with SMTP id 00721157ae682-5a505762c9dso75055897b3.2 for ; Tue, 10 Oct 2023 13:41:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=toxicpanda-com.20230601.gappssmtp.com; s=20230601; t=1696970493; x=1697575293; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:to:from:from:to:cc:subject:date:message-id :reply-to; bh=NKfV0mKcd78LD0F5M7sHTMzeB633X8okqEPfgdPomZI=; b=wSeLYH8qSOP8DCgeRHGEdi+ovvHZlRPviKh3ftbSPwBVFZxdAGj8QdRBMTuiX7z8xu Y7GLI4KR5c3Qx+DUWwEKa1nqyM5CMwhqmZb865TTYnWkqHwysjkYliqiggKB7M8Akbdb 6AqLMX8/HyE9Mb1ZmibMKjGSaEnGvm1OwBw33gDw7yI0KfBC+k4lFSFZTUsrVPpOeGjQ Zfmd+Q7T/tGo40AwUDnFm1zxT3/xogf2OtY9oh3whw9RlSDZBLjgnEUY3SGhgTCCD2dH gZQ76oZDrFQZUG3ZZh93b+t4RPX47B1goBtqPNQ/57g7V7apqOl3eIfyYPe0myh4ap/u zXXw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1696970493; x=1697575293; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=NKfV0mKcd78LD0F5M7sHTMzeB633X8okqEPfgdPomZI=; b=FJMQ6Amek544rwzmuVOb7Nii7d422MG6WIDsbEBsomaFh3YTIMqVFz8+pTimPXsOun gGoGNa6Dx2SAdMdY8zwA5VcD3kOJNP7EALHvZn41g0D4Mw+yDemKW2Cb27AB92Uan7VD MDnMxW4aLHBEbBjI8VTYRBNk47ya5UufuECVjSyy9qt/86IKMR8hZwSEBB7cu/CcjpwI BG/Kvr2ZgyhyzX3kDeFW+qhF0Hb6dTUtIlm++iAVez3ed7CzBlRjOXLSwUGvf6vvB563 zHpmJkznL5rX/NdF1VxwCE92Zy/oyEwi/xCfdgXCWcWHD9MZllQ5949CQBRnXMfu4U+M oD/w== X-Gm-Message-State: AOJu0YyX+XOiYQGWn4WqGJ3oLD+531zzsWp0wHfTTPd7bEseLSRFkrBL LHj0dCAzYuZBA9J6RltC7p6UzQ== X-Google-Smtp-Source: AGHT+IGzD8eE4ccFpvq+0Zb1MfG2ccpgcstraFCLPGLBmuyH6GgOZaY66pNZKwrTU6ioTPzfgJHHaA== X-Received: by 2002:a0d:d546:0:b0:58f:a19f:2b79 with SMTP id x67-20020a0dd546000000b0058fa19f2b79mr20760135ywd.9.1696970493506; Tue, 10 Oct 2023 13:41:33 -0700 (PDT) Received: from localhost (cpe-76-182-20-124.nc.res.rr.com. [76.182.20.124]) by smtp.gmail.com with ESMTPSA id ex5-20020a05690c2fc500b005a7a4e3816esm1213834ywb.89.2023.10.10.13.41.33 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 10 Oct 2023 13:41:33 -0700 (PDT) From: Josef Bacik To: linux-fscrypt@vger.kernel.org, ebiggers@kernel.org, linux-btrfs@vger.kernel.org Subject: [PATCH v2 26/36] btrfs: add an optional encryption context to the end of file extents Date: Tue, 10 Oct 2023 16:40:41 -0400 Message-ID: <8f92ec76d56b2a4c56e34a91c6afdfdb5fc9fa45.1696970227.git.josef@toxicpanda.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org The fscrypt encryption context can be extended to include different things in the future. To facilitate future expansion add an optional btrfs_encryption_info to the end of the file extent. This will hold the size of the context and then will have the binary context tacked onto the end of the extent item. Add the appropriate accessors to make it easy to read this information if we have encryption set, and then update the tree-checker to validate that if this is indeed set properly that the size matches properly. Signed-off-by: Josef Bacik --- fs/btrfs/accessors.h | 48 +++++++++++++++++++++++++++ fs/btrfs/tree-checker.c | 58 ++++++++++++++++++++++++++++----- include/uapi/linux/btrfs_tree.h | 17 +++++++++- 3 files changed, 113 insertions(+), 10 deletions(-) diff --git a/fs/btrfs/accessors.h b/fs/btrfs/accessors.h index 5aaf204fa55f..a54a4671bd15 100644 --- a/fs/btrfs/accessors.h +++ b/fs/btrfs/accessors.h @@ -932,6 +932,10 @@ BTRFS_SETGET_STACK_FUNCS(super_uuid_tree_generation, struct btrfs_super_block, BTRFS_SETGET_STACK_FUNCS(super_nr_global_roots, struct btrfs_super_block, nr_global_roots, 64); +/* struct btrfs_file_extent_encryption_info */ +BTRFS_SETGET_FUNCS(encryption_info_size, struct btrfs_encryption_info, size, + 32); + /* struct btrfs_file_extent_item */ BTRFS_SETGET_STACK_FUNCS(stack_file_extent_type, struct btrfs_file_extent_item, type, 8); @@ -973,6 +977,50 @@ BTRFS_SETGET_FUNCS(file_extent_encryption, struct btrfs_file_extent_item, BTRFS_SETGET_FUNCS(file_extent_other_encoding, struct btrfs_file_extent_item, other_encoding, 16); +static inline struct btrfs_encryption_info *btrfs_file_extent_encryption_info( + const struct btrfs_file_extent_item *ei) +{ + unsigned long offset = (unsigned long)ei; + + offset += offsetof(struct btrfs_file_extent_item, encryption_info); + return (struct btrfs_encryption_info *)offset; +} + +static inline unsigned long btrfs_file_extent_encryption_ctx_offset( + const struct btrfs_file_extent_item *ei) +{ + unsigned long offset = (unsigned long)ei; + + offset += offsetof(struct btrfs_file_extent_item, encryption_info); + return offset + offsetof(struct btrfs_encryption_info, context); +} + +static inline u32 btrfs_file_extent_encryption_ctx_size( + const struct extent_buffer *eb, + const struct btrfs_file_extent_item *ei) +{ + return btrfs_encryption_info_size(eb, + btrfs_file_extent_encryption_info(ei)); +} + +static inline void btrfs_set_file_extent_encryption_ctx_size( + const struct extent_buffer *eb, + struct btrfs_file_extent_item *ei, + u32 val) +{ + btrfs_set_encryption_info_size(eb, + btrfs_file_extent_encryption_info(ei), + val); +} + +static inline u32 btrfs_file_extent_encryption_info_size( + const struct extent_buffer *eb, + const struct btrfs_file_extent_item *ei) +{ + return btrfs_encryption_info_size(eb, + btrfs_file_extent_encryption_info(ei)); +} + /* btrfs_qgroup_status_item */ BTRFS_SETGET_FUNCS(qgroup_status_generation, struct btrfs_qgroup_status_item, generation, 64); diff --git a/fs/btrfs/tree-checker.c b/fs/btrfs/tree-checker.c index 825b235927c6..0b671c1e96f1 100644 --- a/fs/btrfs/tree-checker.c +++ b/fs/btrfs/tree-checker.c @@ -211,6 +211,7 @@ static int check_extent_data_item(struct extent_buffer *leaf, u32 item_size = btrfs_item_size(leaf, slot); u64 extent_end; u8 policy; + u8 fe_type; if (unlikely(!IS_ALIGNED(key->offset, sectorsize))) { file_extent_err(leaf, slot, @@ -241,12 +242,12 @@ static int check_extent_data_item(struct extent_buffer *leaf, SZ_4K); return -EUCLEAN; } - if (unlikely(btrfs_file_extent_type(leaf, fi) >= - BTRFS_NR_FILE_EXTENT_TYPES)) { + + fe_type = btrfs_file_extent_type(leaf, fi); + if (unlikely(fe_type >= BTRFS_NR_FILE_EXTENT_TYPES)) { file_extent_err(leaf, slot, "invalid type for file extent, have %u expect range [0, %u]", - btrfs_file_extent_type(leaf, fi), - BTRFS_NR_FILE_EXTENT_TYPES - 1); + fe_type, BTRFS_NR_FILE_EXTENT_TYPES - 1); return -EUCLEAN; } @@ -295,12 +296,51 @@ static int check_extent_data_item(struct extent_buffer *leaf, return 0; } - /* Regular or preallocated extent has fixed item size */ - if (unlikely(item_size != sizeof(*fi))) { - file_extent_err(leaf, slot, + if (policy == BTRFS_ENCRYPTION_FSCRYPT) { + size_t fe_size = sizeof(*fi) + + sizeof(struct btrfs_encryption_info); + u32 ctxsize; + + if (unlikely(item_size < fe_size)) { + file_extent_err(leaf, slot, + "invalid item size for encrypted file extent, have %u expect = %zu + size of u32", + item_size, sizeof(*fi)); + return -EUCLEAN; + } + + ctxsize = btrfs_file_extent_encryption_info_size(leaf, fi); + if (unlikely(item_size != (fe_size + ctxsize))) { + file_extent_err(leaf, slot, + "invalid item size for encrypted file extent, have %u expect = %zu + context of size %u", + item_size, fe_size, ctxsize); + return -EUCLEAN; + } + + if (unlikely(ctxsize > BTRFS_MAX_EXTENT_CTX_SIZE)) { + file_extent_err(leaf, slot, + "invalid file extent context size, have %u expect a maximum of %u", + ctxsize, BTRFS_MAX_EXTENT_CTX_SIZE); + return -EUCLEAN; + } + + /* + * Only regular and prealloc extents should have an encryption + * context. + */ + if (unlikely(fe_type != BTRFS_FILE_EXTENT_REG && + fe_type != BTRFS_FILE_EXTENT_PREALLOC)) { + file_extent_err(leaf, slot, + "invalid type for encrypted file extent, have %u", + btrfs_file_extent_type(leaf, fi)); + return -EUCLEAN; + } + } else { + if (unlikely(item_size != sizeof(*fi))) { + file_extent_err(leaf, slot, "invalid item size for reg/prealloc file extent, have %u expect %zu", - item_size, sizeof(*fi)); - return -EUCLEAN; + item_size, sizeof(*fi)); + return -EUCLEAN; + } } if (unlikely(CHECK_FE_ALIGNED(leaf, slot, fi, ram_bytes, sectorsize) || CHECK_FE_ALIGNED(leaf, slot, fi, disk_bytenr, sectorsize) || diff --git a/include/uapi/linux/btrfs_tree.h b/include/uapi/linux/btrfs_tree.h index e5a4ba9573a0..98f29f36a359 100644 --- a/include/uapi/linux/btrfs_tree.h +++ b/include/uapi/linux/btrfs_tree.h @@ -1065,12 +1065,24 @@ enum { BTRFS_NR_FILE_EXTENT_TYPES = 3, }; +/* + * Currently just the FSCRYPT_SET_CONTEXT_MAX_SIZE, which is larger than the + * current extent context size from fscrypt, so this should give us plenty of + * breathing room for expansion later. + */ +#define BTRFS_MAX_EXTENT_CTX_SIZE 40 + enum { BTRFS_ENCRYPTION_NONE, BTRFS_ENCRYPTION_FSCRYPT, BTRFS_NR_ENCRYPTION_TYPES, }; +struct btrfs_encryption_info { + __le32 size; + __u8 context[0]; +}; + struct btrfs_file_extent_item { /* * transaction id that created this extent @@ -1126,7 +1138,10 @@ struct btrfs_file_extent_item { * always reflects the size uncompressed and without encoding. */ __le64 num_bytes; - + /* + * the encryption info, if any + */ + struct btrfs_encryption_info encryption_info[0]; } __attribute__ ((__packed__)); struct btrfs_csum_item {