From: Chandan Rajendra <chandan@linux.vnet.ibm.com> To: linux-ext4@vger.kernel.org Cc: Chandan Rajendra <chandan@linux.vnet.ibm.com>, linux-fsdevel@vger.kernel.org, ebiggers3@gmail.com, linux-fscrypt@vger.kernel.org, tytso@mit.edu Subject: [RFC PATCH V2 11/11] ext4: Enable encryption for blocksize less than page size Date: Mon, 12 Feb 2018 15:13:47 +0530 [thread overview] Message-ID: <20180212094347.22071-12-chandan@linux.vnet.ibm.com> (raw) In-Reply-To: <20180212094347.22071-1-chandan@linux.vnet.ibm.com> Now that we have all the code to support encryption for block size less than page size scenario, this commit removes the conditional check in filesystem mount code. The commit also changes the support statement in Documentation/filesystems/fscrypt.rst to reflect the fact that encryption of filesystems with blocksize less than page size now works. Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com> --- Documentation/filesystems/fscrypt.rst | 14 +++++++------- fs/ext4/super.c | 7 ------- 2 files changed, 7 insertions(+), 14 deletions(-) diff --git a/Documentation/filesystems/fscrypt.rst b/Documentation/filesystems/fscrypt.rst index 776ddc6..2147e53 100644 --- a/Documentation/filesystems/fscrypt.rst +++ b/Documentation/filesystems/fscrypt.rst @@ -202,13 +202,13 @@ modes are not currently supported because of the difficulty of dealing with ciphertext expansion. For file contents, each filesystem block is encrypted independently. -Currently, only the case where the filesystem block size is equal to -the system's page size (usually 4096 bytes) is supported. With the -XTS mode of operation (recommended), the logical block number within -the file is used as the IV. With the CBC mode of operation (not -recommended), ESSIV is used; specifically, the IV for CBC is the -logical block number encrypted with AES-256, where the AES-256 key is -the SHA-256 hash of the inode's data encryption key. +Starting from Linux kernel 4.17, encryption of filesystems with block +size less than system's page size is supported. With the XTS mode of +operation (recommended), the logical block number within the file is +used as the IV. With the CBC mode of operation (not recommended), +ESSIV is used; specifically, the IV for CBC is the logical block +number encrypted with AES-256, where the AES-256 key is the SHA-256 +hash of the inode's data encryption key. For filenames, the full filename is encrypted at once. Because of the requirements to retain support for efficient directory lookups and diff --git a/fs/ext4/super.c b/fs/ext4/super.c index ebb7edb..3ec04cc 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -4138,13 +4138,6 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) } } - if ((DUMMY_ENCRYPTION_ENABLED(sbi) || ext4_has_feature_encrypt(sb)) && - (blocksize != PAGE_SIZE)) { - ext4_msg(sb, KERN_ERR, - "Unsupported blocksize for fs encryption"); - goto failed_mount_wq; - } - if (DUMMY_ENCRYPTION_ENABLED(sbi) && !sb_rdonly(sb) && !ext4_has_feature_encrypt(sb)) { ext4_set_feature_encrypt(sb); -- 2.9.5
WARNING: multiple messages have this Message-ID (diff)
From: Chandan Rajendra <chandan@linux.vnet.ibm.com> To: linux-ext4@vger.kernel.org Cc: Chandan Rajendra <chandan@linux.vnet.ibm.com>, linux-fsdevel@vger.kernel.org, ebiggers3@gmail.com, linux-fscrypt@vger.kernel.org, tytso@mit.edu Subject: [RFC PATCH V2 11/11] ext4: Enable encryption for blocksize less than page size Date: Mon, 12 Feb 2018 15:13:47 +0530 [thread overview] Message-ID: <20180212094347.22071-12-chandan@linux.vnet.ibm.com> (raw) In-Reply-To: <20180212094347.22071-1-chandan@linux.vnet.ibm.com> Now that we have all the code to support encryption for block size less than page size scenario, this commit removes the conditional check in filesystem mount code. The commit also changes the support statement in Documentation/filesystems/fscrypt.rst to reflect the fact that encryption of filesystems with blocksize less than page size now works. Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com> --- Documentation/filesystems/fscrypt.rst | 14 +++++++------- fs/ext4/super.c | 7 ------- 2 files changed, 7 insertions(+), 14 deletions(-) diff --git a/Documentation/filesystems/fscrypt.rst b/Documentation/filesystems/fscrypt.rst index 776ddc6..2147e53 100644 --- a/Documentation/filesystems/fscrypt.rst +++ b/Documentation/filesystems/fscrypt.rst @@ -202,13 +202,13 @@ modes are not currently supported because of the difficulty of dealing with ciphertext expansion. For file contents, each filesystem block is encrypted independently. -Currently, only the case where the filesystem block size is equal to -the system's page size (usually 4096 bytes) is supported. With the -XTS mode of operation (recommended), the logical block number within -the file is used as the IV. With the CBC mode of operation (not -recommended), ESSIV is used; specifically, the IV for CBC is the -logical block number encrypted with AES-256, where the AES-256 key is -the SHA-256 hash of the inode's data encryption key. +Starting from Linux kernel 4.17, encryption of filesystems with block +size less than system's page size is supported. With the XTS mode of +operation (recommended), the logical block number within the file is +used as the IV. With the CBC mode of operation (not recommended), +ESSIV is used; specifically, the IV for CBC is the logical block +number encrypted with AES-256, where the AES-256 key is the SHA-256 +hash of the inode's data encryption key. For filenames, the full filename is encrypted at once. Because of the requirements to retain support for efficient directory lookups and diff --git a/fs/ext4/super.c b/fs/ext4/super.c index ebb7edb..3ec04cc 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -4138,13 +4138,6 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) } } - if ((DUMMY_ENCRYPTION_ENABLED(sbi) || ext4_has_feature_encrypt(sb)) && - (blocksize != PAGE_SIZE)) { - ext4_msg(sb, KERN_ERR, - "Unsupported blocksize for fs encryption"); - goto failed_mount_wq; - }
next prev parent reply other threads:[~2018-02-12 9:43 UTC|newest] Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top 2018-02-12 9:43 [RFC PATCH V2 00/11] Ext4 encryption support for blocksize < pagesize Chandan Rajendra 2018-02-12 9:43 ` [RFC PATCH V2 01/11] ext4: Clear BH_Uptodate flag on decryption error Chandan Rajendra 2018-02-12 9:43 ` [RFC PATCH V2 02/11] fs/buffer.c: Export end_buffer_async_read and create_page_buffers Chandan Rajendra 2018-02-12 9:43 ` [RFC PATCH V2 03/11] fs/crypto/: Rename functions to indicate that they operate on FS blocks Chandan Rajendra 2018-02-12 9:43 ` [RFC PATCH V2 04/11] completion_pages: Decrypt all contiguous blocks in a page Chandan Rajendra 2018-02-12 9:43 ` [RFC PATCH V2 05/11] ext4: Decrypt all boundary blocks when doing buffered write Chandan Rajendra 2018-02-21 1:01 ` Eric Biggers 2018-02-21 9:57 ` Chandan Rajendra 2018-02-12 9:43 ` [RFC PATCH V2 06/11] ext4: Decrypt the block that needs to be partially zeroed Chandan Rajendra 2018-02-12 9:43 ` [RFC PATCH V2 07/11] fscrypt_zeroout_range: Encrypt all zeroed out blocks of a page Chandan Rajendra 2018-02-21 1:16 ` Eric Biggers 2018-02-21 9:57 ` Chandan Rajendra 2018-03-26 6:05 ` Theodore Y. Ts'o 2018-03-26 8:22 ` Chandan Rajendra 2018-03-27 19:40 ` Theodore Y. Ts'o 2018-03-28 13:36 ` Chandan Rajendra 2018-04-05 7:03 ` Chandan Rajendra 2018-04-05 12:47 ` Theodore Y. Ts'o 2018-04-05 13:07 ` Chandan Rajendra 2018-04-05 20:50 ` Theodore Y. Ts'o 2018-02-12 9:43 ` [RFC PATCH V2 08/11] Enable reading encrypted files in blocksize less than pagesize setup Chandan Rajendra 2018-02-12 9:43 ` [RFC PATCH V2 09/11] fscrypt: Move completion_pages to crypto/readpage.c Chandan Rajendra 2018-02-12 9:43 ` [RFC PATCH V2 10/11] Enable writing encrypted files in blocksize less than pagesize setup Chandan Rajendra 2018-02-21 0:54 ` Eric Biggers 2018-02-21 9:57 ` Chandan Rajendra 2018-02-21 18:53 ` Eric Biggers 2018-02-12 9:43 ` Chandan Rajendra [this message] 2018-02-12 9:43 ` [RFC PATCH V2 11/11] ext4: Enable encryption for blocksize less than page size Chandan Rajendra 2018-02-21 0:48 ` [RFC PATCH V2 00/11] Ext4 encryption support for blocksize < pagesize Eric Biggers 2018-02-21 9:57 ` Chandan Rajendra 2018-02-21 19:06 ` Eric Biggers 2018-02-22 8:50 ` Chandan Rajendra
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