[PATCH 04/35] blk-crypto: add a process bio callback

[PATCH 04/35] blk-crypto: add a process bio callback

[Josef Bacik]

Btrfs does checksumming, and the checksums need to match the bytes on
disk.  In order to facilitate this add a process bio callback for the
blk-crypto layer.  This allows the file system to specify a callback and
then can process the encrypted bio as necessary.

For btrfs, writes will have the checksums calculated and saved into our
relevant data structures for storage once the write completes.  For
reads we will validate the checksums match what is on disk and error out
if there is a mismatch.

This is incompatible with native encryption obviously, so make sure we
don't use native encryption if this callback is set.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 block/blk-crypto-fallback.c        | 28 ++++++++++++++++++++++++++++
 block/blk-crypto-profile.c         |  2 ++
 block/blk-crypto.c                 |  6 +++++-
 fs/crypto/inline_crypt.c           |  3 ++-
 include/linux/blk-crypto-profile.h |  7 +++++++
 include/linux/blk-crypto.h         |  9 +++++++--
 include/linux/fscrypt.h            | 14 ++++++++++++++
 7 files changed, 65 insertions(+), 4 deletions(-)

diff --git a/block/blk-crypto-fallback.c b/block/blk-crypto-fallback.c
index e6468eab2681..8b4a83534127 100644
--- a/block/blk-crypto-fallback.c
+++ b/block/blk-crypto-fallback.c
@@ -346,6 +346,15 @@ static bool blk_crypto_fallback_encrypt_bio(struct bio **bio_ptr)
 		}
 	}
 
+	/* Process the encrypted bio before we submit it. */
+	if (bc->bc_key->crypto_cfg.process_bio) {
+		blk_st = bc->bc_key->crypto_cfg.process_bio(src_bio, enc_bio);
+		if (blk_st != BLK_STS_OK) {
+			src_bio->bi_status = blk_st;
+			goto out_free_bounce_pages;
+		}
+	}
+
 	enc_bio->bi_private = src_bio;
 	enc_bio->bi_end_io = blk_crypto_fallback_encrypt_endio;
 	*bio_ptr = enc_bio;
@@ -391,6 +400,24 @@ static void blk_crypto_fallback_decrypt_bio(struct work_struct *work)
 	unsigned int i;
 	blk_status_t blk_st;
 
+	/*
+	 * Process the bio first before trying to decrypt.
+	 *
+	 * NOTE: btrfs expects that this bio is the same that was submitted.  If
+	 * at any point this changes we will need to update process_bio to take
+	 * f_ctx->crypt_iter in order to make sure we can iterate the pages for
+	 * checksumming.  We're currently saving this in our btrfs_bio, so this
+	 * works, but if at any point in the future we start allocating a bounce
+	 * bio or something we need to update this callback.
+	 */
+	if (bc->bc_key->crypto_cfg.process_bio) {
+		blk_st = bc->bc_key->crypto_cfg.process_bio(bio, bio);
+		if (blk_st != BLK_STS_OK) {
+			bio->bi_status = blk_st;
+			goto out_no_keyslot;
+		}
+	}
+
 	/*
 	 * Get a blk-crypto-fallback keyslot that contains a crypto_skcipher for
 	 * this bio's algorithm and key.
@@ -560,6 +587,7 @@ static int blk_crypto_fallback_init(void)
 
 	blk_crypto_fallback_profile->ll_ops = blk_crypto_fallback_ll_ops;
 	blk_crypto_fallback_profile->max_dun_bytes_supported = BLK_CRYPTO_MAX_IV_SIZE;
+	blk_crypto_fallback_profile->process_bio_supported = true;
 
 	/* All blk-crypto modes have a crypto API fallback. */
 	for (i = 0; i < BLK_ENCRYPTION_MODE_MAX; i++)
diff --git a/block/blk-crypto-profile.c b/block/blk-crypto-profile.c
index 7fabc883e39f..640cf2ea3fcc 100644
--- a/block/blk-crypto-profile.c
+++ b/block/blk-crypto-profile.c
@@ -352,6 +352,8 @@ bool __blk_crypto_cfg_supported(struct blk_crypto_profile *profile,
 		return false;
 	if (profile->max_dun_bytes_supported < cfg->dun_bytes)
 		return false;
+	if (cfg->process_bio && !profile->process_bio_supported)
+		return false;
 	return true;
 }
 
diff --git a/block/blk-crypto.c b/block/blk-crypto.c
index 4d760b092deb..50556952df19 100644
--- a/block/blk-crypto.c
+++ b/block/blk-crypto.c
@@ -321,6 +321,8 @@ int __blk_crypto_rq_bio_prep(struct request *rq, struct bio *bio,
  * @dun_bytes: number of bytes that will be used to specify the DUN when this
  *	       key is used
  * @data_unit_size: the data unit size to use for en/decryption
+ * @process_bio: the call back if the upper layer needs to process the encrypted
+ *		 bio
  *
  * Return: 0 on success, -errno on failure.  The caller is responsible for
  *	   zeroizing both blk_key and raw_key when done with them.
@@ -328,7 +330,8 @@ int __blk_crypto_rq_bio_prep(struct request *rq, struct bio *bio,
 int blk_crypto_init_key(struct blk_crypto_key *blk_key, const u8 *raw_key,
 			enum blk_crypto_mode_num crypto_mode,
 			unsigned int dun_bytes,
-			unsigned int data_unit_size)
+			unsigned int data_unit_size,
+			blk_crypto_process_bio_t process_bio)
 {
 	const struct blk_crypto_mode *mode;
 
@@ -350,6 +353,7 @@ int blk_crypto_init_key(struct blk_crypto_key *blk_key, const u8 *raw_key,
 	blk_key->crypto_cfg.crypto_mode = crypto_mode;
 	blk_key->crypto_cfg.dun_bytes = dun_bytes;
 	blk_key->crypto_cfg.data_unit_size = data_unit_size;
+	blk_key->crypto_cfg.process_bio = process_bio;
 	blk_key->data_unit_size_bits = ilog2(data_unit_size);
 	blk_key->size = mode->keysize;
 	memcpy(blk_key->raw, raw_key, mode->keysize);
diff --git a/fs/crypto/inline_crypt.c b/fs/crypto/inline_crypt.c
index 21e1851d4ba7..a66a555d84ee 100644
--- a/fs/crypto/inline_crypt.c
+++ b/fs/crypto/inline_crypt.c
@@ -168,7 +168,8 @@ int fscrypt_prepare_inline_crypt_key(struct fscrypt_prepared_key *prep_key,
 		return -ENOMEM;
 
 	err = blk_crypto_init_key(blk_key, raw_key, crypto_mode,
-				  fscrypt_get_dun_bytes(ci), sb->s_blocksize);
+				  fscrypt_get_dun_bytes(ci), sb->s_blocksize,
+				  sb->s_cop->process_bio);
 	if (err) {
 		fscrypt_err(inode, "error %d initializing blk-crypto key", err);
 		goto fail;
diff --git a/include/linux/blk-crypto-profile.h b/include/linux/blk-crypto-profile.h
index 90ab33cb5d0e..3c002e85631a 100644
--- a/include/linux/blk-crypto-profile.h
+++ b/include/linux/blk-crypto-profile.h
@@ -100,6 +100,13 @@ struct blk_crypto_profile {
 	 */
 	struct device *dev;
 
+	/**
+	 * @process_bio_supported: Some things, like btrfs, require the
+	 * encrypted data for checksumming. Drivers set this to true if they can
+	 * handle the process_bio() callback.
+	 */
+	bool process_bio_supported;
+
 	/* private: The following fields shouldn't be accessed by drivers. */
 
 	/* Number of keyslots, or 0 if not applicable */
diff --git a/include/linux/blk-crypto.h b/include/linux/blk-crypto.h
index 5e5822c18ee4..194c1d727013 100644
--- a/include/linux/blk-crypto.h
+++ b/include/linux/blk-crypto.h
@@ -6,7 +6,7 @@
 #ifndef __LINUX_BLK_CRYPTO_H
 #define __LINUX_BLK_CRYPTO_H
 
-#include <linux/types.h>
+#include <linux/blk_types.h>
 
 enum blk_crypto_mode_num {
 	BLK_ENCRYPTION_MODE_INVALID,
@@ -17,6 +17,9 @@ enum blk_crypto_mode_num {
 	BLK_ENCRYPTION_MODE_MAX,
 };
 
+typedef blk_status_t (blk_crypto_process_bio_t)(struct bio *orig_bio,
+						struct bio *enc_bio);
+
 #define BLK_CRYPTO_MAX_KEY_SIZE		64
 /**
  * struct blk_crypto_config - an inline encryption key's crypto configuration
@@ -31,6 +34,7 @@ struct blk_crypto_config {
 	enum blk_crypto_mode_num crypto_mode;
 	unsigned int data_unit_size;
 	unsigned int dun_bytes;
+	blk_crypto_process_bio_t *process_bio;
 };
 
 /**
@@ -90,7 +94,8 @@ bool bio_crypt_dun_is_contiguous(const struct bio_crypt_ctx *bc,
 int blk_crypto_init_key(struct blk_crypto_key *blk_key, const u8 *raw_key,
 			enum blk_crypto_mode_num crypto_mode,
 			unsigned int dun_bytes,
-			unsigned int data_unit_size);
+			unsigned int data_unit_size,
+			blk_crypto_process_bio_t process_bio);
 
 int blk_crypto_start_using_key(struct block_device *bdev,
 			       const struct blk_crypto_key *key);
diff --git a/include/linux/fscrypt.h b/include/linux/fscrypt.h
index 266416742c72..07493ad2588b 100644
--- a/include/linux/fscrypt.h
+++ b/include/linux/fscrypt.h
@@ -16,6 +16,7 @@
 #include <linux/fs.h>
 #include <linux/mm.h>
 #include <linux/slab.h>
+#include <linux/blk-crypto.h>
 #include <uapi/linux/fscrypt.h>
 
 /*
@@ -180,6 +181,19 @@ struct fscrypt_operations {
 	 */
 	struct block_device **(*get_devices)(struct super_block *sb,
 					     unsigned int *num_devs);
+
+	/*
+	 * A callback if the file system requires the ability to process the
+	 * encrypted bio.
+	 *
+	 * @orig_bio: the original bio submitted.
+	 * @enc_bio: the encrypted bio.
+	 *
+	 * For writes the enc_bio will be different from the orig_bio, for reads
+	 * they will be the same.  For reads we get the bio before it is
+	 * decrypted, for writes we get the bio before it is submitted.
+	 */
+	blk_crypto_process_bio_t *process_bio;
 };
 
 static inline struct fscrypt_inode_info *fscrypt_get_info(const struct inode *inode)
-- 
2.41.0

Re: [PATCH 04/35] blk-crypto: add a process bio callback

[kernel test robot]

:::::: 
:::::: Manual check reason: "low confidence bisect report"
:::::: 

BCC: lkp@intel.com
CC: oe-kbuild-all@lists.linux.dev
In-Reply-To: <78be341377e7f0fb0ead3d5167be44ca0c87a944.1695750478.git.josef@toxicpanda.com>
References: <78be341377e7f0fb0ead3d5167be44ca0c87a944.1695750478.git.josef@toxicpanda.com>
TO: Josef Bacik <josef@toxicpanda.com>
TO: linux-btrfs@vger.kernel.org
TO: kernel-team@fb.com
TO: ebiggers@kernel.org
TO: linux-fscrypt@vger.kernel.org
TO: ngompa13@gmail.com

Hi Josef,

kernel test robot noticed the following build warnings:

[auto build test WARNING on kdave/for-next]
[cannot apply to axboe-block/for-next linus/master v6.7-rc3 next-20231201]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Josef-Bacik/fscrypt-rename-fscrypt_info-fscrypt_inode_info/20230927-020531
base:   https://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux.git for-next
patch link:    https://lore.kernel.org/r/78be341377e7f0fb0ead3d5167be44ca0c87a944.1695750478.git.josef%40toxicpanda.com
patch subject: [PATCH 04/35] blk-crypto: add a process bio callback
:::::: branch date: 9 weeks ago
:::::: commit date: 9 weeks ago
compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
reproduce: (https://download.01.org/0day-ci/archive/20231201/202312012352.qjTdmkYN-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/r/202312012352.qjTdmkYN-lkp@intel.com/

includecheck warnings: (new ones prefixed by >>)
>> include/linux/blk-crypto.h: linux/blk_types.h is included more than once.

vim +9 include/linux/blk-crypto.h

     8	
   > 9	#include <linux/blk_types.h>
    10	
    11	enum blk_crypto_mode_num {
    12		BLK_ENCRYPTION_MODE_INVALID,
    13		BLK_ENCRYPTION_MODE_AES_256_XTS,
    14		BLK_ENCRYPTION_MODE_AES_128_CBC_ESSIV,
    15		BLK_ENCRYPTION_MODE_ADIANTUM,
    16		BLK_ENCRYPTION_MODE_SM4_XTS,
    17		BLK_ENCRYPTION_MODE_MAX,
    18	};
    19	
    20	typedef blk_status_t (blk_crypto_process_bio_t)(struct bio *orig_bio,
    21							struct bio *enc_bio);
    22	
    23	#define BLK_CRYPTO_MAX_KEY_SIZE		64
    24	/**
    25	 * struct blk_crypto_config - an inline encryption key's crypto configuration
    26	 * @crypto_mode: encryption algorithm this key is for
    27	 * @data_unit_size: the data unit size for all encryption/decryptions with this
    28	 *	key.  This is the size in bytes of each individual plaintext and
    29	 *	ciphertext.  This is always a power of 2.  It might be e.g. the
    30	 *	filesystem block size or the disk sector size.
    31	 * @dun_bytes: the maximum number of bytes of DUN used when using this key
    32	 */
    33	struct blk_crypto_config {
    34		enum blk_crypto_mode_num crypto_mode;
    35		unsigned int data_unit_size;
    36		unsigned int dun_bytes;
    37		blk_crypto_process_bio_t *process_bio;
    38	};
    39	
    40	/**
    41	 * struct blk_crypto_key - an inline encryption key
    42	 * @crypto_cfg: the crypto configuration (like crypto_mode, key size) for this
    43	 *		key
    44	 * @data_unit_size_bits: log2 of data_unit_size
    45	 * @size: size of this key in bytes (determined by @crypto_cfg.crypto_mode)
    46	 * @raw: the raw bytes of this key.  Only the first @size bytes are used.
    47	 *
    48	 * A blk_crypto_key is immutable once created, and many bios can reference it at
    49	 * the same time.  It must not be freed until all bios using it have completed
    50	 * and it has been evicted from all devices on which it may have been used.
    51	 */
    52	struct blk_crypto_key {
    53		struct blk_crypto_config crypto_cfg;
    54		unsigned int data_unit_size_bits;
    55		unsigned int size;
    56		u8 raw[BLK_CRYPTO_MAX_KEY_SIZE];
    57	};
    58	
    59	#define BLK_CRYPTO_MAX_IV_SIZE		32
    60	#define BLK_CRYPTO_DUN_ARRAY_SIZE	(BLK_CRYPTO_MAX_IV_SIZE / sizeof(u64))
    61	
    62	/**
    63	 * struct bio_crypt_ctx - an inline encryption context
    64	 * @bc_key: the key, algorithm, and data unit size to use
    65	 * @bc_dun: the data unit number (starting IV) to use
    66	 *
    67	 * A bio_crypt_ctx specifies that the contents of the bio will be encrypted (for
    68	 * write requests) or decrypted (for read requests) inline by the storage device
    69	 * or controller, or by the crypto API fallback.
    70	 */
    71	struct bio_crypt_ctx {
    72		const struct blk_crypto_key	*bc_key;
    73		u64				bc_dun[BLK_CRYPTO_DUN_ARRAY_SIZE];
    74	};
    75	
  > 76	#include <linux/blk_types.h>
    77	#include <linux/blkdev.h>
    78	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

RE: [PATCH 04/35] blk-crypto: add a process bio callback

[Liu, Yujie]

not_report

9 weeks ago patch.

Date: Tue, 26 Sep 2023 14:01:30 -0400

-----Original Message-----
From: lkp <lkp@intel.com> 
Sent: Friday, December 1, 2023 23:23
To: oe-kbuild@lists.linux.dev
Cc: lkp <lkp@intel.com>
Subject: Re: [PATCH 04/35] blk-crypto: add a process bio callback

:::::: 
:::::: Manual check reason: "low confidence bisect report"
:::::: 

BCC: lkp@intel.com
CC: oe-kbuild-all@lists.linux.dev
In-Reply-To: <78be341377e7f0fb0ead3d5167be44ca0c87a944.1695750478.git.josef@toxicpanda.com>
References: <78be341377e7f0fb0ead3d5167be44ca0c87a944.1695750478.git.josef@toxicpanda.com>
TO: Josef Bacik <josef@toxicpanda.com>
TO: linux-btrfs@vger.kernel.org
TO: kernel-team@fb.com
TO: ebiggers@kernel.org
TO: linux-fscrypt@vger.kernel.org
TO: ngompa13@gmail.com

Hi Josef,

kernel test robot noticed the following build warnings:

[auto build test WARNING on kdave/for-next]
[cannot apply to axboe-block/for-next linus/master v6.7-rc3 next-20231201]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Josef-Bacik/fscrypt-rename-fscrypt_info-fscrypt_inode_info/20230927-020531
base:   https://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux.git for-next
patch link:    https://lore.kernel.org/r/78be341377e7f0fb0ead3d5167be44ca0c87a944.1695750478.git.josef%40toxicpanda.com
patch subject: [PATCH 04/35] blk-crypto: add a process bio callback
:::::: branch date: 9 weeks ago
:::::: commit date: 9 weeks ago
compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
reproduce: (https://download.01.org/0day-ci/archive/20231201/202312012352.qjTdmkYN-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/r/202312012352.qjTdmkYN-lkp@intel.com/

includecheck warnings: (new ones prefixed by >>)
>> include/linux/blk-crypto.h: linux/blk_types.h is included more than once.

vim +9 include/linux/blk-crypto.h

     8	
   > 9	#include <linux/blk_types.h>
    10	
    11	enum blk_crypto_mode_num {
    12		BLK_ENCRYPTION_MODE_INVALID,
    13		BLK_ENCRYPTION_MODE_AES_256_XTS,
    14		BLK_ENCRYPTION_MODE_AES_128_CBC_ESSIV,
    15		BLK_ENCRYPTION_MODE_ADIANTUM,
    16		BLK_ENCRYPTION_MODE_SM4_XTS,
    17		BLK_ENCRYPTION_MODE_MAX,
    18	};
    19	
    20	typedef blk_status_t (blk_crypto_process_bio_t)(struct bio *orig_bio,
    21							struct bio *enc_bio);
    22	
    23	#define BLK_CRYPTO_MAX_KEY_SIZE		64
    24	/**
    25	 * struct blk_crypto_config - an inline encryption key's crypto configuration
    26	 * @crypto_mode: encryption algorithm this key is for
    27	 * @data_unit_size: the data unit size for all encryption/decryptions with this
    28	 *	key.  This is the size in bytes of each individual plaintext and
    29	 *	ciphertext.  This is always a power of 2.  It might be e.g. the
    30	 *	filesystem block size or the disk sector size.
    31	 * @dun_bytes: the maximum number of bytes of DUN used when using this key
    32	 */
    33	struct blk_crypto_config {
    34		enum blk_crypto_mode_num crypto_mode;
    35		unsigned int data_unit_size;
    36		unsigned int dun_bytes;
    37		blk_crypto_process_bio_t *process_bio;
    38	};
    39	
    40	/**
    41	 * struct blk_crypto_key - an inline encryption key
    42	 * @crypto_cfg: the crypto configuration (like crypto_mode, key size) for this
    43	 *		key
    44	 * @data_unit_size_bits: log2 of data_unit_size
    45	 * @size: size of this key in bytes (determined by @crypto_cfg.crypto_mode)
    46	 * @raw: the raw bytes of this key.  Only the first @size bytes are used.
    47	 *
    48	 * A blk_crypto_key is immutable once created, and many bios can reference it at
    49	 * the same time.  It must not be freed until all bios using it have completed
    50	 * and it has been evicted from all devices on which it may have been used.
    51	 */
    52	struct blk_crypto_key {
    53		struct blk_crypto_config crypto_cfg;
    54		unsigned int data_unit_size_bits;
    55		unsigned int size;
    56		u8 raw[BLK_CRYPTO_MAX_KEY_SIZE];
    57	};
    58	
    59	#define BLK_CRYPTO_MAX_IV_SIZE		32
    60	#define BLK_CRYPTO_DUN_ARRAY_SIZE	(BLK_CRYPTO_MAX_IV_SIZE / sizeof(u64))
    61	
    62	/**
    63	 * struct bio_crypt_ctx - an inline encryption context
    64	 * @bc_key: the key, algorithm, and data unit size to use
    65	 * @bc_dun: the data unit number (starting IV) to use
    66	 *
    67	 * A bio_crypt_ctx specifies that the contents of the bio will be encrypted (for
    68	 * write requests) or decrypted (for read requests) inline by the storage device
    69	 * or controller, or by the crypto API fallback.
    70	 */
    71	struct bio_crypt_ctx {
    72		const struct blk_crypto_key	*bc_key;
    73		u64				bc_dun[BLK_CRYPTO_DUN_ARRAY_SIZE];
    74	};
    75	
  > 76	#include <linux/blk_types.h>
    77	#include <linux/blkdev.h>
    78	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki