diff mbox series

[v2,1/3] dm-inlinecrypt: Add inline encryption support

Message ID 20240916085741.1636554-2-quic_mdalam@quicinc.com
State New
Headers show
Series Add inline encryption support | expand

Commit Message

Md Sadre Alam Sept. 16, 2024, 8:57 a.m. UTC
QCOM SDCC controller supports Inline Crypto Engine
This driver will enables inline encryption/decryption
for ICE. The algorithm supported by ICE are XTS(AES)
and CBC(AES).

Signed-off-by: Md Sadre Alam <quic_mdalam@quicinc.com>
---

Change in [v2]

* Added dm-inlinecrypt driver support

* squash the patch blk-crypto: Add additional algo modes for Inline
  encryption and md: dm-crypt: Add additional algo modes for inline
  encryption and added in this

Change in [v1]

* This patch was not included in [v1]

 block/blk-crypto.c           |  21 +++
 drivers/md/Kconfig           |   8 +
 drivers/md/Makefile          |   1 +
 drivers/md/dm-inline-crypt.c | 316 +++++++++++++++++++++++++++++++++++
 include/linux/blk-crypto.h   |   3 +
 5 files changed, 349 insertions(+)
 create mode 100644 drivers/md/dm-inline-crypt.c

Comments

kernel test robot Sept. 17, 2024, 5:05 a.m. UTC | #1
Hi Md,

kernel test robot noticed the following build errors:

[auto build test ERROR on device-mapper-dm/for-next]
[also build test ERROR on axboe-block/for-next linus/master song-md/md-next v6.11 next-20240916]
[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/Md-Sadre-Alam/dm-inlinecrypt-Add-inline-encryption-support/20240916-170452
base:   https://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm.git for-next
patch link:    https://lore.kernel.org/r/20240916085741.1636554-2-quic_mdalam%40quicinc.com
patch subject: [PATCH v2 1/3] dm-inlinecrypt: Add inline encryption support
config: openrisc-randconfig-r062-20240917 (https://download.01.org/0day-ci/archive/20240917/202409171209.aEtxsPez-lkp@intel.com/config)
compiler: or1k-linux-gcc (GCC) 14.1.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240917/202409171209.aEtxsPez-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/oe-kbuild-all/202409171209.aEtxsPez-lkp@intel.com/

All errors (new ones prefixed by >>):

   drivers/md/dm-inline-crypt.c: In function 'crypt_prepare_inline_crypt_key':
>> drivers/md/dm-inline-crypt.c:81:15: error: implicit declaration of function 'blk_crypto_init_key' [-Wimplicit-function-declaration]
      81 |         ret = blk_crypto_init_key(cc->blk_key, cc->key, cc->crypto_mode,
         |               ^~~~~~~~~~~~~~~~~~~
>> drivers/md/dm-inline-crypt.c:88:15: error: implicit declaration of function 'blk_crypto_start_using_key' [-Wimplicit-function-declaration]
      88 |         ret = blk_crypto_start_using_key(cc->dev->bdev, cc->blk_key);
         |               ^~~~~~~~~~~~~~~~~~~~~~~~~~
   drivers/md/dm-inline-crypt.c: In function 'crypt_destroy_inline_crypt_key':
>> drivers/md/dm-inline-crypt.c:104:17: error: implicit declaration of function 'blk_crypto_evict_key'; did you mean 'blk_crypto_register'? [-Wimplicit-function-declaration]
     104 |                 blk_crypto_evict_key(cc->dev->bdev, cc->blk_key);
         |                 ^~~~~~~~~~~~~~~~~~~~
         |                 blk_crypto_register
   drivers/md/dm-inline-crypt.c: In function 'crypt_inline_encrypt_submit':
>> drivers/md/dm-inline-crypt.c:121:17: error: implicit declaration of function 'bio_crypt_set_ctx' [-Wimplicit-function-declaration]
     121 |                 bio_crypt_set_ctx(bio, cc->blk_key, dun, GFP_KERNEL);
         |                 ^~~~~~~~~~~~~~~~~


vim +/blk_crypto_init_key +81 drivers/md/dm-inline-crypt.c

    72	
    73	static int crypt_prepare_inline_crypt_key(struct inlinecrypt_config *cc)
    74	{
    75		int ret;
    76	
    77		cc->blk_key = kzalloc(sizeof(*cc->blk_key), GFP_KERNEL);
    78		if (!cc->blk_key)
    79			return -ENOMEM;
    80	
  > 81		ret = blk_crypto_init_key(cc->blk_key, cc->key, cc->crypto_mode,
    82					  cc->iv_size, cc->sector_size);
    83		if (ret) {
    84			DMERR("Failed to init inline encryption key");
    85			goto bad_key;
    86		}
    87	
  > 88		ret = blk_crypto_start_using_key(cc->dev->bdev, cc->blk_key);
    89		if (ret) {
    90			DMERR("Failed to use inline encryption key");
    91			goto bad_key;
    92		}
    93	
    94		return 0;
    95	bad_key:
    96		kfree_sensitive(cc->blk_key);
    97		cc->blk_key = NULL;
    98		return ret;
    99	}
   100	
   101	static void crypt_destroy_inline_crypt_key(struct inlinecrypt_config *cc)
   102	{
   103		if (cc->blk_key) {
 > 104			blk_crypto_evict_key(cc->dev->bdev, cc->blk_key);
   105			kfree_sensitive(cc->blk_key);
   106			cc->blk_key = NULL;
   107		}
   108	}
   109	
   110	static void crypt_inline_encrypt_submit(struct dm_target *ti, struct bio *bio)
   111	{
   112		struct inlinecrypt_config *cc = ti->private;
   113		u64 dun[BLK_CRYPTO_DUN_ARRAY_SIZE];
   114	
   115		bio_set_dev(bio, cc->dev->bdev);
   116		if (bio_sectors(bio)) {
   117			memset(dun, 0, BLK_CRYPTO_MAX_IV_SIZE);
   118			bio->bi_iter.bi_sector = cc->start +
   119				dm_target_offset(ti, bio->bi_iter.bi_sector);
   120			dun[0] = le64_to_cpu(bio->bi_iter.bi_sector + cc->iv_offset);
 > 121			bio_crypt_set_ctx(bio, cc->blk_key, dun, GFP_KERNEL);
   122		}
   123	
   124		submit_bio_noacct(bio);
   125	}
   126
kernel test robot Sept. 17, 2024, 6:38 a.m. UTC | #2
Hi Md,

kernel test robot noticed the following build warnings:

[auto build test WARNING on device-mapper-dm/for-next]
[also build test WARNING on axboe-block/for-next linus/master song-md/md-next v6.11 next-20240916]
[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/Md-Sadre-Alam/dm-inlinecrypt-Add-inline-encryption-support/20240916-170452
base:   https://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm.git for-next
patch link:    https://lore.kernel.org/r/20240916085741.1636554-2-quic_mdalam%40quicinc.com
patch subject: [PATCH v2 1/3] dm-inlinecrypt: Add inline encryption support
config: x86_64-allyesconfig (https://download.01.org/0day-ci/archive/20240917/202409171440.qx2iOkY3-lkp@intel.com/config)
compiler: clang version 18.1.8 (https://github.com/llvm/llvm-project 3b5b5c1ec4a3095ab096dd780e84d7ab81f3d7ff)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240917/202409171440.qx2iOkY3-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/oe-kbuild-all/202409171440.qx2iOkY3-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> drivers/md/dm-inline-crypt.c:198:6: warning: variable 'ret' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
     198 |         if ((sscanf(argv[2], "%llu%c", &tmpll, &dummy) != 1) ||
         |             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     199 |             (tmpll & ((cc->sector_size >> SECTOR_SHIFT) - 1))) {
         |             ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   drivers/md/dm-inline-crypt.c:250:9: note: uninitialized use occurs here
     250 |         return ret;
         |                ^~~
   drivers/md/dm-inline-crypt.c:198:2: note: remove the 'if' if its condition is always false
     198 |         if ((sscanf(argv[2], "%llu%c", &tmpll, &dummy) != 1) ||
         |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     199 |             (tmpll & ((cc->sector_size >> SECTOR_SHIFT) - 1))) {
         |             ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     200 |                 ti->error = "Invalid iv_offset sector";
         |                 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     201 |                 goto bad;
         |                 ~~~~~~~~~
     202 |         }
         |         ~
>> drivers/md/dm-inline-crypt.c:198:6: warning: variable 'ret' is used uninitialized whenever '||' condition is true [-Wsometimes-uninitialized]
     198 |         if ((sscanf(argv[2], "%llu%c", &tmpll, &dummy) != 1) ||
         |             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   drivers/md/dm-inline-crypt.c:250:9: note: uninitialized use occurs here
     250 |         return ret;
         |                ^~~
   drivers/md/dm-inline-crypt.c:198:6: note: remove the '||' if its condition is always false
     198 |         if ((sscanf(argv[2], "%llu%c", &tmpll, &dummy) != 1) ||
         |             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   drivers/md/dm-inline-crypt.c:178:9: note: initialize the variable 'ret' to silence this warning
     178 |         int ret;
         |                ^
         |                 = 0
   2 warnings generated.


vim +198 drivers/md/dm-inline-crypt.c

   168	
   169	static int inlinecrypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
   170	{
   171		struct inlinecrypt_config *cc;
   172		char *cipher_api = NULL;
   173		char *cipher, *chainmode;
   174		unsigned long long tmpll;
   175		char *ivmode;
   176		int key_size;
   177		char dummy;
   178		int ret;
   179	
   180		if (argc < 5) {
   181			ti->error = "Not enough arguments";
   182			return -EINVAL;
   183		}
   184	
   185		key_size = strlen(argv[1]) >> 1;
   186	
   187		cc = kzalloc(struct_size(cc, key, key_size), GFP_KERNEL);
   188		if (!cc) {
   189			ti->error = "Cannot allocate encryption context";
   190			return -ENOMEM;
   191		}
   192		cc->key_size = key_size;
   193		cc->sector_size = (1 << SECTOR_SHIFT);
   194		cc->sector_shift = 0;
   195	
   196		ti->private = cc;
   197	
 > 198		if ((sscanf(argv[2], "%llu%c", &tmpll, &dummy) != 1) ||
   199		    (tmpll & ((cc->sector_size >> SECTOR_SHIFT) - 1))) {
   200			ti->error = "Invalid iv_offset sector";
   201			goto bad;
   202		}
   203		cc->iv_offset = tmpll;
   204	
   205		ret = dm_get_device(ti, argv[3], dm_table_get_mode(ti->table),
   206				    &cc->dev);
   207		if (ret) {
   208			ti->error = "Device lookup failed";
   209			goto bad;
   210		}
   211	
   212		ret = -EINVAL;
   213		if (sscanf(argv[4], "%llu%c", &tmpll, &dummy) != 1 ||
   214		    tmpll != (sector_t)tmpll) {
   215			ti->error = "Invalid device sector";
   216			goto bad;
   217		}
   218	
   219		cc->start = tmpll;
   220	
   221		cipher = strsep(&argv[0], "-");
   222		chainmode = strsep(&argv[0], "-");
   223		ivmode = strsep(&argv[0], "-");
   224	
   225		cipher_api = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL);
   226		if (!cipher_api)
   227			goto bad;
   228	
   229		ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME,
   230			       "%s(%s)", chainmode, cipher);
   231		if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) {
   232			kfree(cipher_api);
   233			ret = -ENOMEM;
   234			goto bad;
   235		}
   236	
   237		ret = crypt_select_inline_crypt_mode(ti, cipher_api, ivmode);
   238	
   239		/* Initialize and set key */
   240		ret = inlinecrypt_set_key(cc, argv[1]);
   241		if (ret < 0) {
   242			ti->error = "Error decoding and setting key";
   243			return ret;
   244		}
   245	
   246		return 0;
   247	bad:
   248		ti->error = "Error in inlinecrypt mapping";
   249		inlinecrypt_dtr(ti);
   250		return ret;
   251	}
   252
kernel test robot Sept. 18, 2024, 5:08 a.m. UTC | #3
Hi Md,

kernel test robot noticed the following build warnings:

[auto build test WARNING on device-mapper-dm/for-next]
[also build test WARNING on axboe-block/for-next linus/master song-md/md-next v6.11 next-20240917]
[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/Md-Sadre-Alam/dm-inlinecrypt-Add-inline-encryption-support/20240916-170452
base:   https://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm.git for-next
patch link:    https://lore.kernel.org/r/20240916085741.1636554-2-quic_mdalam%40quicinc.com
patch subject: [PATCH v2 1/3] dm-inlinecrypt: Add inline encryption support
config: csky-randconfig-r111-20240918 (https://download.01.org/0day-ci/archive/20240918/202409181233.1FrQNVtU-lkp@intel.com/config)
compiler: csky-linux-gcc (GCC) 14.1.0
reproduce: (https://download.01.org/0day-ci/archive/20240918/202409181233.1FrQNVtU-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/oe-kbuild-all/202409181233.1FrQNVtU-lkp@intel.com/

sparse warnings: (new ones prefixed by >>)
>> drivers/md/dm-inline-crypt.c:120:26: sparse: sparse: cast to restricted __le64
   drivers/md/dm-inline-crypt.c:214:32: sparse: sparse: self-comparison always evaluates to false

vim +120 drivers/md/dm-inline-crypt.c

   109	
   110	static void crypt_inline_encrypt_submit(struct dm_target *ti, struct bio *bio)
   111	{
   112		struct inlinecrypt_config *cc = ti->private;
   113		u64 dun[BLK_CRYPTO_DUN_ARRAY_SIZE];
   114	
   115		bio_set_dev(bio, cc->dev->bdev);
   116		if (bio_sectors(bio)) {
   117			memset(dun, 0, BLK_CRYPTO_MAX_IV_SIZE);
   118			bio->bi_iter.bi_sector = cc->start +
   119				dm_target_offset(ti, bio->bi_iter.bi_sector);
 > 120			dun[0] = le64_to_cpu(bio->bi_iter.bi_sector + cc->iv_offset);
   121			bio_crypt_set_ctx(bio, cc->blk_key, dun, GFP_KERNEL);
   122		}
   123	
   124		submit_bio_noacct(bio);
   125	}
   126
Eric Biggers Sept. 21, 2024, 6:55 p.m. UTC | #4
Hi,

On Mon, Sep 16, 2024 at 02:27:39PM +0530, Md Sadre Alam wrote:
> QCOM SDCC controller supports Inline Crypto Engine
> This driver will enables inline encryption/decryption
> for ICE. The algorithm supported by ICE are XTS(AES)
> and CBC(AES).
> 
> Signed-off-by: Md Sadre Alam <quic_mdalam@quicinc.com>
> ---
> 
> Change in [v2]
> 
> * Added dm-inlinecrypt driver support
> 
> * squash the patch blk-crypto: Add additional algo modes for Inline
>   encryption and md: dm-crypt: Add additional algo modes for inline
>   encryption and added in this
> 
> Change in [v1]
> 
> * This patch was not included in [v1]
> 
>  block/blk-crypto.c           |  21 +++
>  drivers/md/Kconfig           |   8 +
>  drivers/md/Makefile          |   1 +
>  drivers/md/dm-inline-crypt.c | 316 +++++++++++++++++++++++++++++++++++
>  include/linux/blk-crypto.h   |   3 +
>  5 files changed, 349 insertions(+)
>  create mode 100644 drivers/md/dm-inline-crypt.c

Thanks for working on this!  Android uses a similar device-mapper target called
dm-default-key
(https://android.googlesource.com/kernel/common/+/refs/heads/android-mainline/drivers/md/dm-default-key.c),
and I've been looking for the best way to get the functionality upstream.  The
main challenge is that dm-default-key is integrated with fscrypt, such that if
fscrypt encrypts the data, then the data isn't also encrypted with the block
device key.  There are also cases such as f2fs garbage collection in which
filesystems read/write raw data without en/decryption by any key.  So
essentially a passthrough mode is supported on individual I/O requests.

It looks like this patch not only does not support that, but it ignores the
existence of fscrypt (or any other use of inline encryption by filesystems)
entirely, and overrides any filesystem-provided key with the block device's.  At
the very least, this case would need to be explicitly not supported initially,
i.e. dm-inlinecrypt would error out if the upper layer already provided a key.

But I would like there to be an agreed-upon way to extend the code to support
the pass-through mode, so that filesystem and block device level encryption work
properly together.  It can indeed be done with a device-mapper target (as
Android does already), whether it's called "dm-inlinecrypt" or "dm-default-key",
but not in a standalone way: pass-through requests also require an addition to
struct bio and some support in block and filesystem code.  Previously, people
have said that supporting this functionality natively in the block layer would
be a better fit than a dm target (e.g., see the thread
https://lore.kernel.org/all/1658316391-13472-1-git-send-email-israelr@nvidia.com/T/#u).
I'd appreciate people's feedback on which approach they'd prefer.

Anyway, assuming the device-mapper target approach, I also have some other
feedback on this patch:

New algorithms should not be added in the same patch as a new dm target.  Also,
I do not see why there is any need for the new algorithms you are adding
(AES-128-XTS, AES-128-CBC, and AES-256-CBC).  XTS is preferable to CBC, and
AES-256 is preferable to AES-128.  AES-256-XTS is already supported, both by
blk-crypto and by Qualcomm ICE.  So you should just use AES-256-XTS.

There are also a lot of miscellaneous issues with the proposed code.  Missing
->io_hints and ->status methods, truncating IVs to 32 bits, unnecessarily using
a custom algorithm name syntax that doesn't make the IV generation method
explicit, unnecessarily splitting bios, incrementing IVs every 512 bytes instead
of each sector, etc.  I can comment on all of these in detail if you want, but
to start it might be helpful to just check out dm-default-key
(https://android.googlesource.com/kernel/common/+/refs/heads/android-mainline/drivers/md/dm-default-key.c)
and maybe base your code on that, as it has handled these issues already.  E.g.,
its syntax is aligned with dm-crypt's, it implements ->io_hints and ->status,
and it calculates the maximum DUN correctly so that it can be determined
correctly whether the inline encryption hardware can be used or not.

Finally, the commit message needs to summarize what the patch does and what its
motivation is.  Currently it just talks about the Qualcomm ICE driver and
doesn't actually say anything about dm-inlinecrypt.  Yes, the motivation for
dm-inlinecrypt involves being able to take advantage of inline encryption
hardware such as Qualcomm ICE, but it's not explained.

Thanks,

- Eric
Christoph Hellwig Sept. 24, 2024, 7:44 a.m. UTC | #5
On Sat, Sep 21, 2024 at 11:55:19AM -0700, Eric Biggers wrote:
> (https://android.googlesource.com/kernel/common/+/refs/heads/android-mainline/drivers/md/dm-default-key.c),
> and I've been looking for the best way to get the functionality upstream.  The
> main challenge is that dm-default-key is integrated with fscrypt, such that if
> fscrypt encrypts the data, then the data isn't also encrypted with the block
> device key.  There are also cases such as f2fs garbage collection in which
> filesystems read/write raw data without en/decryption by any key.  So
> essentially a passthrough mode is supported on individual I/O requests.

Adding a default key is not the job of a block remapping driver.  You'll
need to fit that into the file system and/or file system level helpers.

> 
> It looks like this patch not only does not support that, but it ignores the
> existence of fscrypt (or any other use of inline encryption by filesystems)
> entirely, and overrides any filesystem-provided key with the block device's.  At
> the very least, this case would need to be explicitly not supported initially,
> i.e. dm-inlinecrypt would error out if the upper layer already provided a key.

I agree that we have an incompatibility here, but simply erroring out
feels like the wrong way to approach the stacking.  If a stacking driver
consumes the inline encryption capability it must not advertise it to
the upper layers.
Eric Biggers Sept. 24, 2024, 10:04 p.m. UTC | #6
On Tue, Sep 24, 2024 at 12:44:53AM -0700, Christoph Hellwig wrote:
> On Sat, Sep 21, 2024 at 11:55:19AM -0700, Eric Biggers wrote:
> > (https://android.googlesource.com/kernel/common/+/refs/heads/android-mainline/drivers/md/dm-default-key.c),
> > and I've been looking for the best way to get the functionality upstream.  The
> > main challenge is that dm-default-key is integrated with fscrypt, such that if
> > fscrypt encrypts the data, then the data isn't also encrypted with the block
> > device key.  There are also cases such as f2fs garbage collection in which
> > filesystems read/write raw data without en/decryption by any key.  So
> > essentially a passthrough mode is supported on individual I/O requests.
> 
> Adding a default key is not the job of a block remapping driver.  You'll
> need to fit that into the file system and/or file system level helpers.

What about a block device ioctl, as was previously proposed
(https://lore.kernel.org/linux-block/1658316391-13472-1-git-send-email-israelr@nvidia.com/T/#u)?

> > It looks like this patch not only does not support that, but it ignores the
> > existence of fscrypt (or any other use of inline encryption by filesystems)
> > entirely, and overrides any filesystem-provided key with the block device's.  At
> > the very least, this case would need to be explicitly not supported initially,
> > i.e. dm-inlinecrypt would error out if the upper layer already provided a key.
> 
> I agree that we have an incompatibility here, but simply erroring out
> feels like the wrong way to approach the stacking.  If a stacking driver
> consumes the inline encryption capability it must not advertise it to
> the upper layers.

Right, I missed that's actually already how it works.  The crypto capabilities
are only passed through if the target sets DM_TARGET_PASSES_CRYPTO.

- Eric
Christoph Hellwig Oct. 1, 2024, 8:37 a.m. UTC | #7
On Tue, Sep 24, 2024 at 03:04:34PM -0700, Eric Biggers wrote:
> What about a block device ioctl, as was previously proposed
> (https://lore.kernel.org/linux-block/1658316391-13472-1-git-send-email-israelr@nvidia.com/T/#u)?

No.  This is a file system layer policy and needs to sit entirely above
the block layer instead of breaking abstraction boundaries.
Mikulas Patocka Oct. 15, 2024, 10:59 a.m. UTC | #8
Hi

The patch seems OK. Should it go in via the device mapper tree or the 
block layer tree?


On Mon, 16 Sep 2024, Md Sadre Alam wrote:

> +#define DM_CRYPT_DEFAULT_MAX_READ_SIZE		131072
> +#define DM_CRYPT_DEFAULT_MAX_WRITE_SIZE		131072
> +
> +static unsigned int get_max_request_size(struct inlinecrypt_config *cc, bool wrt)
> +{
> +	unsigned int val, sector_align;
> +
> +	val = !wrt ? DM_CRYPT_DEFAULT_MAX_READ_SIZE : DM_CRYPT_DEFAULT_MAX_WRITE_SIZE;
> +	if (wrt) {
> +		if (unlikely(val > BIO_MAX_VECS << PAGE_SHIFT))
> +			val = BIO_MAX_VECS << PAGE_SHIFT;
> +	}
> +	sector_align = max(bdev_logical_block_size(cc->dev->bdev), (unsigned int)cc->sector_size);
> +	val = round_down(val, sector_align);
> +	if (unlikely(!val))
> +		val = sector_align;
> +	return val >> SECTOR_SHIFT;
> +}

This piece of code was copied from the dm-crypt target. For dm-crypt, I 
was actually benchmarking the performance for various 
DM_CRYPT_DEFAULT_MAX_READ_SIZE and DM_CRYPT_DEFAULT_MAX_WRITE_SIZE values 
and I selected the values that resulted in the best performance.

You should benchmark it too to find the optimal I/O size. Perhaps you find 
out that there is no need to split big requests and this piece of code can 
be dropped.

> +               /* Omit the key for now. */
> +               DMEMIT("%s - %llu %s %llu", ctx->cipher_string, ctx->iv_offset,
> +                      ctx->dev->name, (unsigned long long)ctx->start);

What if someone reloads the table? I think you should display the key. 
dmsetup does not display the key if the "--showkeys" parameter is not 
specified.

Mikulas
Adrian Vovk Oct. 18, 2024, 3:03 p.m. UTC | #9
On October 18, 2024 1:56:38 AM EDT, Christoph Hellwig <hch@infradead.org> wrote:
>On Fri, Oct 18, 2024 at 01:44:19AM -0400, Adrian Vovk wrote:
>> > So just run a target on each partition.
>> 
>> 
>> That has different semantics. If I encrypt each virtual partition there's
>> nothing encrypting the metadata around the virtual partitions. Of course,
>> this is a rather contrived example but point stands, the semantics are
>> different.
>
>Then you set up an dm-crype device mapper table for the partition table as
>well.

Sure, but then this way you're encrypting each partition twice. Once by the dm-crypt inside of the partition, and again by the dm-crypt that's under the partition table. This double encryption is ruinous for performance, so it's just not a feasible solution and thus people don't do this. Would be nice if we had the flexibility though.

Plus, I'm not sure that such a double encryption approach is even feasible with blk-crypto. Is the blk-crypto engine capable of receiving two keys and encrypting twice with them?

>
>> > This is the prime example of why allowing higher layers to skip
>> > encryption is a no-go.
>> >
>> 
>> In what way does that break the file system's security model? Could you
>> elaborate on what's objectionable about the behavior here?
>
>Because you are now bypassing encryption for certainl LBA ranges in
>the file system based on hints/flags for something sitting way above
>in the stack.
>

Well the data is still encrypted. It's just encrypted with a different key. If the attacker has a FDE dump of the disk, the data is still just as inaccessible to them.

In fact, allowing for this will let us tighten up security instead of punching holes. It would let us put encrypted home directories on top of full-disk encryption. So if an attacker has a disk image and the FDE key, they still wouldn't be able to decrypt the user's home directory because they'd need more keys. We also want to put fscrypt on top of the encrypted home directories to encrypt each app data directory, so if you have a banking app the attacker wouldn't be able to get that app's data even if they manage to get your home directory key. Right now, doing something like this requires stacking encryption and is thus unfeasible and we can't do it, so we're stuck with one layer of full disk encryption and no isolation between users and apps.

Thanks,
Adrian
Christoph Hellwig Oct. 23, 2024, 6:57 a.m. UTC | #10
On Fri, Oct 18, 2024 at 11:03:50AM -0400, Adrian Vovk wrote:
> Sure, but then this way you're encrypting each partition twice. Once by the dm-crypt inside of the partition, and again by the dm-crypt that's under the partition table. This double encryption is ruinous for performance, so it's just not a feasible solution and thus people don't do this. Would be nice if we had the flexibility though.

Why do you assume the encryption would happen twice?

> >Because you are now bypassing encryption for certainl LBA ranges in
> >the file system based on hints/flags for something sitting way above
> >in the stack.
> >
> 
> Well the data is still encrypted. It's just encrypted with a different key. If the attacker has a FDE dump of the disk, the data is still just as inaccessible to them.

No one knows that it actually is encryped.  The lower layer just knows
the skip encryption flag was set, but it has zero assurance data
actually was encrypted.
Adrian Vovk Oct. 24, 2024, 3:17 a.m. UTC | #11
> Alternatively, if I recall correctly it should be possible to just
> check if the bio has an attached encryption context. If it has one,
> then just pass-through. If it doesn't, then attach your own. No flag
> required this way, and dm-default-key would only add encryption iff
> the data isn't already encrypted.

This piqued my interest, so I went and did some git archeology to see
why this isn't the case and there's a flag now. Apparently fscrypt
will sometimes rearrange blocks without the key present. This is fine,
because if there's no key, blk-crypto doesn't need to do anything and
we can just shuffle the encrypted data around. We definitely don't
want to re-encrypt the data in that scenario.

Also, thinking about it a bit more: what should happen if we stack
dm-crypt on top of dm-default-key. I see no point in double-encrypting
even in this situation. So, dm-crypt would set the flag to skip
dm-default-key, even though it's not actually attaching an encryption
context to the bio.

So it seems like the flag is the better solution. It would just be
impermissible to set the flag on a request that will write plaintext
data to disk.

- Adrian
Christoph Hellwig Oct. 24, 2024, 6:14 a.m. UTC | #12
On Wed, Oct 23, 2024 at 10:52:06PM -0400, Adrian Vovk wrote:
> > Why do you assume the encryption would happen twice?
> 
> I'm not assuming. That's the behavior of dm-crypt without passthrough.
> It just encrypts everything that moves through it. If I stack two
> layers of dm-crypt on top of each other my data is encrypted twice.

Sure.  But why would you do that?

> > No one knows that it actually is encryped.  The lower layer just knows
> > the skip encryption flag was set, but it has zero assurance data
> > actually was encrypted.
> 
> I think it makes sense to require that the data is actually encrypted
> whenever the flag is set. Of course there's no way to enforce that
> programmatically, but code that sets the flag without making sure the
> data gets encrypted some other way wouldn't pass review.

You have a lot of trusted in reviers. But even that doesn't help as
the kernel can load code that never passed review.

> Alternatively, if I recall correctly it should be possible to just
> check if the bio has an attached encryption context. If it has one,
> then just pass-through. If it doesn't, then attach your own. No flag
> required this way, and dm-default-key would only add encryption iff
> the data isn't already encrypted.

That at least sounds a little better.  But it still doesn't answer
why we need this hack instead always encrypting at one layer instead
of splitting it up.
Adrian Vovk Oct. 24, 2024, 3:32 p.m. UTC | #13
On Thu, Oct 24, 2024 at 5:04 AM Christoph Hellwig <hch@infradead.org> wrote:
> Can you please fix your mailer?  It's creating crazy long lines
> that are completely unreadable.

Sorry about that. Apparently that happens when I send from mobile, and
I couldn't find a setting to change it. I'll stick to replying from
the computer from now on. I've re-attached the message below, so that
it gets wrapped properly

On October 24, 2024 2:14:57 AM EDT, Christoph Hellwig <hch@infradead.org> wrote:
>On Wed, Oct 23, 2024 at 10:52:06PM -0400, Adrian Vovk wrote:
>> > Why do you assume the encryption would happen twice?
>>
>> I'm not assuming. That's the behavior of dm-crypt without passthrough.
>> It just encrypts everything that moves through it. If I stack two
>> layers of dm-crypt on top of each other my data is encrypted twice.
>
>Sure.  But why would you do that?

As mentioned earlier in the thread: I don't have a usecase
specifically for this and it was an example of a situation where
passthrough is necessary and no filesystem is involved at all. Though,
as I also pointed out, a usecase where you're putting encrypted
virtual partitions on an encrypted LVM setup isn't all that absurd.

In my real-world case, I'm putting encrypted loop devices on top of a
filesystem that holds its own sensitive data. Each loop device has
dm-crypt inside and uses a unique key, but the filesystem needs to be
encrypted too (because, again, it has its own sensitive data outside
of the loop devices). The loop devices cannot be put onto their own
separate partition because there's no good way to know ahead of time
how much space either of the partitions would need: sometimes the loop
devices need to take up loads of space on the partition, and other
times the non-loop-device data needs to take up that space. And to top
it all off, the distribution of allocated space needs to change
dynamically.

The current Linux kernel does not support this use-case without double
encryption. The loop devices are encrypted once with their own
dm-crypt instance. Then that same data is encrypted a second time over
by the partition.

Actually this scenario is simplified. We actually want to use fscrypt
inside of the loopback file too. So actually, without the passthrough
mechanism some data would be encrypted three distinct times.

>> > No one knows that it actually is encryped.  The lower layer just knows
>> > the skip encryption flag was set, but it has zero assurance data
>> > actually was encrypted.
>>
>> I think it makes sense to require that the data is actually encrypted
>> whenever the flag is set. Of course there's no way to enforce that
>> programmatically, but code that sets the flag without making sure the
>> data gets encrypted some other way wouldn't pass review.
>
>You have a lot of trusted in reviers. But even that doesn't help as
>the kernel can load code that never passed review.

Ultimately, I'm unsure what the concern is here.

It's a glaringly loud opt-in marker that encryption was already
performed or is otherwise intentionally unnecessary. The flag existing
isn't what punches through the security model. It's the use of the
flag that does. I can't imagine anything setting the flag by accident.
So what are you actually concerned about? How are you expecting this
flag to actually be misused?

As for third party modules that might punch holes, so what? 3rd party
modules aren't the kernel's responsibility or problem

>> Alternatively, if I recall correctly it should be possible to just
>> check if the bio has an attached encryption context. If it has one,
>> then just pass-through. If it doesn't, then attach your own. No flag
>> required this way, and dm-default-key would only add encryption iff
>> the data isn't already encrypted.
>
>That at least sounds a little better.

Please see my follow up. This is actually not feasible because it
doesn't work. Sometimes, fscrypt will just ask to move encrypted
blocks around without providing an encryption context; the data
doesn't need to be decrypted to be reshuffled on disk. This flag-less
approach I describe would actually just break: it it would
unintentionally encrypt that data during shuffling.

> But it still doesn't answer
>why we need this hack instead always encrypting at one layer instead
>of splitting it up.

In my loopback file scenario, what would be the one layer that could
handle the encryption?

- the loopback files are just regular files that happen to have
encrypted data inside of them. Doing it a different way changes the
semantics: with a loopback file, I'm able to move it into a basic FAT
filesystem and back without losing the encryption on the data

- the filesystem is completely unaware of any encryption. The loopback
files are just files with random content inside. The filesystem itself
is encrypted from below by the block layer. So, there's nothing for it
to do.

- the underlying instance of dm-crypt is encrypting a single opaque
blob of data, and so without explicit communication from above it
cannot possibly know how to handle this.

Thus, I don't see a single layer that can handle this. The only
solution is for upper layers to communicate downward.

Best,
Adrian

On Thu, Oct 24, 2024 at 5:04 AM Christoph Hellwig <hch@infradead.org> wrote:
>
> On Thu, Oct 24, 2024 at 03:52:24AM -0400, Adrian Vovk wrote:
> > >
> > >Sure.  But why would you do that?
> >
> > As mentioned earlier in the thread: I don't have a usecase specifically for this and it was an example of a situation where passthrough is necessary and no filesystem is involved at all. Though, as I also pointed out, a usecase where you're putting encrypted virtual partitions on an encrypted LVM setup isn't all that absurd.
>
> Can you please fix your mailer?  It's creating crazy long lines
> that are completely unreadable.
>
Adrian Vovk Oct. 24, 2024, 4:23 p.m. UTC | #14
On Thu, Oct 24, 2024 at 11:59 AM Christoph Hellwig <hch@infradead.org> wrote:
>
> On Thu, Oct 24, 2024 at 11:32:58AM -0400, Adrian Vovk wrote:
> > >> I'm not assuming. That's the behavior of dm-crypt without passthrough.
> > >> It just encrypts everything that moves through it. If I stack two
> > >> layers of dm-crypt on top of each other my data is encrypted twice.
> > >
> > >Sure.  But why would you do that?
> >
> > As mentioned earlier in the thread: I don't have a usecase
> > specifically for this and it was an example of a situation where
> > passthrough is necessary and no filesystem is involved at all. Though,
> > as I also pointed out, a usecase where you're putting encrypted
> > virtual partitions on an encrypted LVM setup isn't all that absurd.
>
> It's a little odd but not entirely absurd indeed.  But it can also
> be easily handled by setting up a dm-crypt table just for the
> partition table.

That doesn't cover it. Not all of the virtual partitions necessarily
need to have their own dm-crypt, so they should be encrypted by the
underlying dm-crypt.

So the dm-crypt doesn't just need to cover the partition table, but
also arbitrary ranges within the whole partition

> > In my real-world case, I'm putting encrypted loop devices on top of a
> > filesystem that holds its own sensitive data. Each loop device has
> > dm-crypt inside and uses a unique key, but the filesystem needs to be
> > encrypted too (because, again, it has its own sensitive data outside
> > of the loop devices). The loop devices cannot be put onto their own
> > separate partition because there's no good way to know ahead of time
> > how much space either of the partitions would need: sometimes the loop
> > devices need to take up loads of space on the partition, and other
> > times the non-loop-device data needs to take up that space. And to top
> > it all off, the distribution of allocated space needs to change
> > dynamically.
>
> And that's exactly the case I worry about.  The file system can't
> trust a layer entirely above it.  If we want to be able to have a
> space pool between a file systems with one encryption policy and
> images with another we'll need to replace the loop driver with a
> block driver taking blocks from the file system space pool.  Which
> might be a good idea for various other reasons.

I don't quite understand the difference between a loopback file, and a
block driver that uses space from a filesystem space pool. Isn't that
what a loopback file is?

>
> > Ultimately, I'm unsure what the concern is here.
> >
> > It's a glaringly loud opt-in marker that encryption was already
> > performed or is otherwise intentionally unnecessary. The flag existing
> > isn't what punches through the security model. It's the use of the
> > flag that does. I can't imagine anything setting the flag by accident.
> > So what are you actually concerned about? How are you expecting this
> > flag to actually be misused?
> >
> > As for third party modules that might punch holes, so what? 3rd party
> > modules aren't the kernel's responsibility or problem
>
> On the one hand they are not.  On the other if you have a file system
> encryption scheme that is bypassed by a random other loadable code
> setting a single flag I would not consider it very trust worth or in
> fact actively dangerous.

I'd expect that the lower encryption layer has an opt-in flag to turn
on and off passthrough functionality. I think I neglected to mention
that before; it was discussed in other threads and I just kinda
assumed that it would be there.

So, with that in mind: the loadable code could set the flag, but the
underlying dm-inlinecrypt would need to opt into the weaker security
too. If the system administrator has opted the lower layer into
passthrough, then they've considered the risks of what could happen if
an upper layer sets the flag and decided that it's OK. If the
administrator didn't opt in, then the flag has no effect. Does that
sound more acceptable?

>
> > In my loopback file scenario, what would be the one layer that could
> > handle the encryption?
>
> But getting rid of loopback devices.

I can't get rid of the loopback devices. They're an essential part of
this. I should be able to take the encrypted loopback file, send it to
a different machine, and have it keep working the same as it always
has.

Without the loopback device, I'm stuck with fscrypt. Which isn't
supported by all filesystems, and encrypts much less data than we
require.

- Adrian
diff mbox series

Patch

diff --git a/block/blk-crypto.c b/block/blk-crypto.c
index 4d760b092deb..e5bc3c7a405b 100644
--- a/block/blk-crypto.c
+++ b/block/blk-crypto.c
@@ -19,6 +19,12 @@ 
 #include "blk-crypto-internal.h"
 
 const struct blk_crypto_mode blk_crypto_modes[] = {
+	[BLK_ENCRYPTION_MODE_AES_128_XTS] = {
+		.name = "AES-128-XTS",
+		.cipher_str = "xts(aes)",
+		.keysize = 32,
+		.ivsize = 16,
+	},
 	[BLK_ENCRYPTION_MODE_AES_256_XTS] = {
 		.name = "AES-256-XTS",
 		.cipher_str = "xts(aes)",
@@ -43,6 +49,18 @@  const struct blk_crypto_mode blk_crypto_modes[] = {
 		.keysize = 32,
 		.ivsize = 16,
 	},
+	[BLK_ENCRYPTION_MODE_AES_128_CBC] = {
+		.name = "AES-128-CBC",
+		.cipher_str = "cbc(aes)",
+		.keysize = 16,
+		.ivsize = 16,
+	},
+	[BLK_ENCRYPTION_MODE_AES_256_CBC] = {
+		.name = "AES-256-CBC",
+		.cipher_str = "cbc(aes)",
+		.keysize = 32,
+		.ivsize = 16,
+	},
 };
 
 /*
@@ -106,6 +124,7 @@  void bio_crypt_set_ctx(struct bio *bio, const struct blk_crypto_key *key,
 
 	bio->bi_crypt_context = bc;
 }
+EXPORT_SYMBOL_GPL(bio_crypt_set_ctx);
 
 void __bio_crypt_free_ctx(struct bio *bio)
 {
@@ -356,6 +375,7 @@  int blk_crypto_init_key(struct blk_crypto_key *blk_key, const u8 *raw_key,
 
 	return 0;
 }
+EXPORT_SYMBOL_GPL(blk_crypto_init_key);
 
 bool blk_crypto_config_supported_natively(struct block_device *bdev,
 					  const struct blk_crypto_config *cfg)
@@ -398,6 +418,7 @@  int blk_crypto_start_using_key(struct block_device *bdev,
 		return 0;
 	return blk_crypto_fallback_start_using_mode(key->crypto_cfg.crypto_mode);
 }
+EXPORT_SYMBOL_GPL(blk_crypto_start_using_key);
 
 /**
  * blk_crypto_evict_key() - Evict a blk_crypto_key from a block_device
diff --git a/drivers/md/Kconfig b/drivers/md/Kconfig
index 1e9db8e4acdf..272a6a3274bb 100644
--- a/drivers/md/Kconfig
+++ b/drivers/md/Kconfig
@@ -270,6 +270,14 @@  config DM_CRYPT
 
 	  If unsure, say N.
 
+config DM_INLINE_CRYPT
+	tristate "Inline crypt target support"
+	depends on BLK_DEV_DM || COMPILE_TEST
+	help
+	  This inline crypt device-mapper target allows to create a device
+	  that transparently encrypts the data on it using inline crypto HW
+	  engine.
+
 config DM_SNAPSHOT
        tristate "Snapshot target"
        depends on BLK_DEV_DM
diff --git a/drivers/md/Makefile b/drivers/md/Makefile
index 476a214e4bdc..0e09b7665803 100644
--- a/drivers/md/Makefile
+++ b/drivers/md/Makefile
@@ -51,6 +51,7 @@  obj-$(CONFIG_DM_UNSTRIPED)	+= dm-unstripe.o
 obj-$(CONFIG_DM_BUFIO)		+= dm-bufio.o
 obj-$(CONFIG_DM_BIO_PRISON)	+= dm-bio-prison.o
 obj-$(CONFIG_DM_CRYPT)		+= dm-crypt.o
+obj-$(CONFIG_DM_INLINE_CRYPT)  += dm-inline-crypt.o
 obj-$(CONFIG_DM_DELAY)		+= dm-delay.o
 obj-$(CONFIG_DM_DUST)		+= dm-dust.o
 obj-$(CONFIG_DM_FLAKEY)		+= dm-flakey.o
diff --git a/drivers/md/dm-inline-crypt.c b/drivers/md/dm-inline-crypt.c
new file mode 100644
index 000000000000..e94f86a3a5e0
--- /dev/null
+++ b/drivers/md/dm-inline-crypt.c
@@ -0,0 +1,316 @@ 
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2024, Qualcomm Innovation Center, Inc. All rights reserved
+ *
+ * Based on work by Israel Rukshin file: dm-crypt.c
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/bio.h>
+#include <linux/blkdev.h>
+#include <linux/crypto.h>
+#include <linux/blk-crypto.h>
+#include <linux/device-mapper.h>
+
+#define DM_MSG_PREFIX "inline-crypt"
+
+struct inlinecrypt_config {
+	struct dm_dev *dev;
+	sector_t start;
+	u64 iv_offset;
+	unsigned int iv_size;
+	unsigned short sector_size;
+	unsigned char sector_shift;
+	unsigned int key_size;
+	enum blk_crypto_mode_num crypto_mode;
+	struct blk_crypto_key *blk_key;
+	u8 key[] __counted_by(key_size);
+};
+
+#define DM_CRYPT_DEFAULT_MAX_READ_SIZE		131072
+#define DM_CRYPT_DEFAULT_MAX_WRITE_SIZE		131072
+
+static unsigned int get_max_request_size(struct inlinecrypt_config *cc, bool wrt)
+{
+	unsigned int val, sector_align;
+
+	val = !wrt ? DM_CRYPT_DEFAULT_MAX_READ_SIZE : DM_CRYPT_DEFAULT_MAX_WRITE_SIZE;
+	if (wrt) {
+		if (unlikely(val > BIO_MAX_VECS << PAGE_SHIFT))
+			val = BIO_MAX_VECS << PAGE_SHIFT;
+	}
+	sector_align = max(bdev_logical_block_size(cc->dev->bdev), (unsigned int)cc->sector_size);
+	val = round_down(val, sector_align);
+	if (unlikely(!val))
+		val = sector_align;
+	return val >> SECTOR_SHIFT;
+}
+
+static int crypt_select_inline_crypt_mode(struct dm_target *ti, char *cipher,
+					  char *ivmode)
+{
+	struct inlinecrypt_config *cc = ti->private;
+
+	if (strcmp(cipher, "xts(aes128)") == 0) {
+		cc->crypto_mode = BLK_ENCRYPTION_MODE_AES_128_XTS;
+	} else if (strcmp(cipher, "xts(aes256)") == 0) {
+		cc->crypto_mode = BLK_ENCRYPTION_MODE_AES_256_XTS;
+	} else if (strcmp(cipher, "cbc(aes128)") == 0) {
+		cc->crypto_mode = BLK_ENCRYPTION_MODE_AES_128_CBC;
+	} else if (strcmp(cipher, "cbc(aes256)") == 0) {
+		cc->crypto_mode = BLK_ENCRYPTION_MODE_AES_256_CBC;
+	} else {
+		ti->error = "Invalid cipher for inline_crypt";
+		return -EINVAL;
+	}
+
+	cc->iv_size = 4;
+
+	return 0;
+}
+
+static int crypt_prepare_inline_crypt_key(struct inlinecrypt_config *cc)
+{
+	int ret;
+
+	cc->blk_key = kzalloc(sizeof(*cc->blk_key), GFP_KERNEL);
+	if (!cc->blk_key)
+		return -ENOMEM;
+
+	ret = blk_crypto_init_key(cc->blk_key, cc->key, cc->crypto_mode,
+				  cc->iv_size, cc->sector_size);
+	if (ret) {
+		DMERR("Failed to init inline encryption key");
+		goto bad_key;
+	}
+
+	ret = blk_crypto_start_using_key(cc->dev->bdev, cc->blk_key);
+	if (ret) {
+		DMERR("Failed to use inline encryption key");
+		goto bad_key;
+	}
+
+	return 0;
+bad_key:
+	kfree_sensitive(cc->blk_key);
+	cc->blk_key = NULL;
+	return ret;
+}
+
+static void crypt_destroy_inline_crypt_key(struct inlinecrypt_config *cc)
+{
+	if (cc->blk_key) {
+		blk_crypto_evict_key(cc->dev->bdev, cc->blk_key);
+		kfree_sensitive(cc->blk_key);
+		cc->blk_key = NULL;
+	}
+}
+
+static void crypt_inline_encrypt_submit(struct dm_target *ti, struct bio *bio)
+{
+	struct inlinecrypt_config *cc = ti->private;
+	u64 dun[BLK_CRYPTO_DUN_ARRAY_SIZE];
+
+	bio_set_dev(bio, cc->dev->bdev);
+	if (bio_sectors(bio)) {
+		memset(dun, 0, BLK_CRYPTO_MAX_IV_SIZE);
+		bio->bi_iter.bi_sector = cc->start +
+			dm_target_offset(ti, bio->bi_iter.bi_sector);
+		dun[0] = le64_to_cpu(bio->bi_iter.bi_sector + cc->iv_offset);
+		bio_crypt_set_ctx(bio, cc->blk_key, dun, GFP_KERNEL);
+	}
+
+	submit_bio_noacct(bio);
+}
+
+static int inlinecrypt_setkey(struct inlinecrypt_config *cc)
+{
+	crypt_destroy_inline_crypt_key(cc);
+
+	return crypt_prepare_inline_crypt_key(cc);
+
+	return 0;
+}
+
+static int inlinecrypt_set_key(struct inlinecrypt_config *cc, char *key)
+{
+	int r = -EINVAL;
+	int key_string_len = strlen(key);
+
+	/* Decode key from its hex representation. */
+	if (cc->key_size && hex2bin(cc->key, key, cc->key_size) < 0)
+		goto out;
+
+	r = inlinecrypt_setkey(cc);
+out:
+	memset(key, '0', key_string_len);
+
+	return r;
+}
+
+static void inlinecrypt_dtr(struct dm_target *ti)
+{
+	struct inlinecrypt_config *cc = ti->private;
+
+	ti->private = NULL;
+
+	if (!cc)
+		return;
+
+	crypt_destroy_inline_crypt_key(cc);
+
+	if (cc->dev)
+		dm_put_device(ti, cc->dev);
+
+	kfree_sensitive(cc);
+}
+
+static int inlinecrypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
+{
+	struct inlinecrypt_config *cc;
+	char *cipher_api = NULL;
+	char *cipher, *chainmode;
+	unsigned long long tmpll;
+	char *ivmode;
+	int key_size;
+	char dummy;
+	int ret;
+
+	if (argc < 5) {
+		ti->error = "Not enough arguments";
+		return -EINVAL;
+	}
+
+	key_size = strlen(argv[1]) >> 1;
+
+	cc = kzalloc(struct_size(cc, key, key_size), GFP_KERNEL);
+	if (!cc) {
+		ti->error = "Cannot allocate encryption context";
+		return -ENOMEM;
+	}
+	cc->key_size = key_size;
+	cc->sector_size = (1 << SECTOR_SHIFT);
+	cc->sector_shift = 0;
+
+	ti->private = cc;
+
+	if ((sscanf(argv[2], "%llu%c", &tmpll, &dummy) != 1) ||
+	    (tmpll & ((cc->sector_size >> SECTOR_SHIFT) - 1))) {
+		ti->error = "Invalid iv_offset sector";
+		goto bad;
+	}
+	cc->iv_offset = tmpll;
+
+	ret = dm_get_device(ti, argv[3], dm_table_get_mode(ti->table),
+			    &cc->dev);
+	if (ret) {
+		ti->error = "Device lookup failed";
+		goto bad;
+	}
+
+	ret = -EINVAL;
+	if (sscanf(argv[4], "%llu%c", &tmpll, &dummy) != 1 ||
+	    tmpll != (sector_t)tmpll) {
+		ti->error = "Invalid device sector";
+		goto bad;
+	}
+
+	cc->start = tmpll;
+
+	cipher = strsep(&argv[0], "-");
+	chainmode = strsep(&argv[0], "-");
+	ivmode = strsep(&argv[0], "-");
+
+	cipher_api = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL);
+	if (!cipher_api)
+		goto bad;
+
+	ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME,
+		       "%s(%s)", chainmode, cipher);
+	if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) {
+		kfree(cipher_api);
+		ret = -ENOMEM;
+		goto bad;
+	}
+
+	ret = crypt_select_inline_crypt_mode(ti, cipher_api, ivmode);
+
+	/* Initialize and set key */
+	ret = inlinecrypt_set_key(cc, argv[1]);
+	if (ret < 0) {
+		ti->error = "Error decoding and setting key";
+		return ret;
+	}
+
+	return 0;
+bad:
+	ti->error = "Error in inlinecrypt mapping";
+	inlinecrypt_dtr(ti);
+	return ret;
+}
+
+static int inlinecrypt_map(struct dm_target *ti, struct bio *bio)
+{
+	struct inlinecrypt_config *cc = ti->private;
+	unsigned int max_sectors;
+
+	/*
+	 * If bio is REQ_PREFLUSH or REQ_OP_DISCARD, just bypass crypt queues.
+	 * - for REQ_PREFLUSH device-mapper core ensures that no IO is in-flight
+	 * - for REQ_OP_DISCARD caller must use flush if IO ordering matters
+	 */
+	if (unlikely(bio->bi_opf & REQ_PREFLUSH ||
+		     bio_op(bio) == REQ_OP_DISCARD)) {
+		bio_set_dev(bio, cc->dev->bdev);
+		if (bio_sectors(bio))
+			bio->bi_iter.bi_sector = cc->start +
+				dm_target_offset(ti, bio->bi_iter.bi_sector);
+		return DM_MAPIO_REMAPPED;
+	}
+
+	/*
+	 * Check if bio is too large, split as needed.
+	 */
+	max_sectors = get_max_request_size(cc, bio_data_dir(bio) == WRITE);
+	if (unlikely(bio_sectors(bio) > max_sectors))
+		dm_accept_partial_bio(bio, max_sectors);
+
+	/*
+	 * Ensure that bio is a multiple of internal sector eninlinecryption size
+	 * and is aligned to this size as defined in IO hints.
+	 */
+	if (unlikely((bio->bi_iter.bi_sector & ((cc->sector_size >> SECTOR_SHIFT) - 1)) != 0))
+		return DM_MAPIO_KILL;
+
+	if (unlikely(bio->bi_iter.bi_size & (cc->sector_size - 1)))
+		return DM_MAPIO_KILL;
+
+	crypt_inline_encrypt_submit(ti, bio);
+		return DM_MAPIO_SUBMITTED;
+
+	return 0;
+}
+
+static int inlinecrypt_iterate_devices(struct dm_target *ti,
+				       iterate_devices_callout_fn fn, void *data)
+{
+	struct inlinecrypt_config *cc = ti->private;
+
+	return fn(ti, cc->dev, cc->start, ti->len, data);
+}
+
+static struct target_type inlinecrypt_target = {
+	.name   = "inline-crypt",
+	.version = {1, 0, 0},
+	.module = THIS_MODULE,
+	.ctr    = inlinecrypt_ctr,
+	.dtr    = inlinecrypt_dtr,
+	.map    = inlinecrypt_map,
+	.iterate_devices = inlinecrypt_iterate_devices,
+};
+module_dm(inlinecrypt);
+
+MODULE_AUTHOR("Md Sadre Alam <quic_mdalam@quicinc.com>");
+MODULE_DESCRIPTION(DM_NAME " target for inline encryption / decryption");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/blk-crypto.h b/include/linux/blk-crypto.h
index 5e5822c18ee4..da503a05c5f6 100644
--- a/include/linux/blk-crypto.h
+++ b/include/linux/blk-crypto.h
@@ -10,10 +10,13 @@ 
 
 enum blk_crypto_mode_num {
 	BLK_ENCRYPTION_MODE_INVALID,
+	BLK_ENCRYPTION_MODE_AES_128_XTS,
 	BLK_ENCRYPTION_MODE_AES_256_XTS,
 	BLK_ENCRYPTION_MODE_AES_128_CBC_ESSIV,
 	BLK_ENCRYPTION_MODE_ADIANTUM,
 	BLK_ENCRYPTION_MODE_SM4_XTS,
+	BLK_ENCRYPTION_MODE_AES_128_CBC,
+	BLK_ENCRYPTION_MODE_AES_256_CBC,
 	BLK_ENCRYPTION_MODE_MAX,
 };