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path: root/drivers/md/dm-crypt.c
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Diffstat (limited to 'drivers/md/dm-crypt.c')
-rw-r--r--drivers/md/dm-crypt.c78
1 files changed, 66 insertions, 12 deletions
diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 08a40f4e4f6..a1086ee8ccc 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -20,6 +20,7 @@
#include <asm/atomic.h>
#include <linux/scatterlist.h>
#include <asm/page.h>
+#include <asm/unaligned.h>
#include "dm.h"
@@ -85,7 +86,10 @@ struct crypt_config {
*/
struct crypt_iv_operations *iv_gen_ops;
char *iv_mode;
- struct crypto_cipher *iv_gen_private;
+ union {
+ struct crypto_cipher *essiv_tfm;
+ int benbi_shift;
+ } iv_gen_private;
sector_t iv_offset;
unsigned int iv_size;
@@ -101,7 +105,7 @@ struct crypt_config {
#define MIN_POOL_PAGES 32
#define MIN_BIO_PAGES 8
-static kmem_cache_t *_crypt_io_pool;
+static struct kmem_cache *_crypt_io_pool;
/*
* Different IV generation algorithms:
@@ -113,6 +117,9 @@ static kmem_cache_t *_crypt_io_pool;
* encrypted with the bulk cipher using a salt as key. The salt
* should be derived from the bulk cipher's key via hashing.
*
+ * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1
+ * (needed for LRW-32-AES and possible other narrow block modes)
+ *
* plumb: unimplemented, see:
* http://article.gmane.org/gmane.linux.kernel.device-mapper.dm-crypt/454
*/
@@ -191,21 +198,61 @@ static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti,
}
kfree(salt);
- cc->iv_gen_private = essiv_tfm;
+ cc->iv_gen_private.essiv_tfm = essiv_tfm;
return 0;
}
static void crypt_iv_essiv_dtr(struct crypt_config *cc)
{
- crypto_free_cipher(cc->iv_gen_private);
- cc->iv_gen_private = NULL;
+ crypto_free_cipher(cc->iv_gen_private.essiv_tfm);
+ cc->iv_gen_private.essiv_tfm = NULL;
}
static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv, sector_t sector)
{
memset(iv, 0, cc->iv_size);
*(u64 *)iv = cpu_to_le64(sector);
- crypto_cipher_encrypt_one(cc->iv_gen_private, iv, iv);
+ crypto_cipher_encrypt_one(cc->iv_gen_private.essiv_tfm, iv, iv);
+ return 0;
+}
+
+static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti,
+ const char *opts)
+{
+ unsigned int bs = crypto_blkcipher_blocksize(cc->tfm);
+ int log = long_log2(bs);
+
+ /* we need to calculate how far we must shift the sector count
+ * to get the cipher block count, we use this shift in _gen */
+
+ if (1 << log != bs) {
+ ti->error = "cypher blocksize is not a power of 2";
+ return -EINVAL;
+ }
+
+ if (log > 9) {
+ ti->error = "cypher blocksize is > 512";
+ return -EINVAL;
+ }
+
+ cc->iv_gen_private.benbi_shift = 9 - log;
+
+ return 0;
+}
+
+static void crypt_iv_benbi_dtr(struct crypt_config *cc)
+{
+}
+
+static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv, sector_t sector)
+{
+ __be64 val;
+
+ memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */
+
+ val = cpu_to_be64(((u64)sector << cc->iv_gen_private.benbi_shift) + 1);
+ put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64)));
+
return 0;
}
@@ -219,13 +266,18 @@ static struct crypt_iv_operations crypt_iv_essiv_ops = {
.generator = crypt_iv_essiv_gen
};
+static struct crypt_iv_operations crypt_iv_benbi_ops = {
+ .ctr = crypt_iv_benbi_ctr,
+ .dtr = crypt_iv_benbi_dtr,
+ .generator = crypt_iv_benbi_gen
+};
static int
crypt_convert_scatterlist(struct crypt_config *cc, struct scatterlist *out,
struct scatterlist *in, unsigned int length,
int write, sector_t sector)
{
- u8 iv[cc->iv_size];
+ u8 iv[cc->iv_size] __attribute__ ((aligned(__alignof__(u64))));
struct blkcipher_desc desc = {
.tfm = cc->tfm,
.info = iv,
@@ -458,11 +510,11 @@ static void dec_pending(struct crypt_io *io, int error)
* interrupt context.
*/
static struct workqueue_struct *_kcryptd_workqueue;
-static void kcryptd_do_work(void *data);
+static void kcryptd_do_work(struct work_struct *work);
static void kcryptd_queue_io(struct crypt_io *io)
{
- INIT_WORK(&io->work, kcryptd_do_work, io);
+ INIT_WORK(&io->work, kcryptd_do_work);
queue_work(_kcryptd_workqueue, &io->work);
}
@@ -618,9 +670,9 @@ static void process_read_endio(struct crypt_io *io)
dec_pending(io, crypt_convert(cc, &ctx));
}
-static void kcryptd_do_work(void *data)
+static void kcryptd_do_work(struct work_struct *work)
{
- struct crypt_io *io = data;
+ struct crypt_io *io = container_of(work, struct crypt_io, work);
if (io->post_process)
process_read_endio(io);
@@ -768,7 +820,7 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
cc->tfm = tfm;
/*
- * Choose ivmode. Valid modes: "plain", "essiv:<esshash>".
+ * Choose ivmode. Valid modes: "plain", "essiv:<esshash>", "benbi".
* See comments at iv code
*/
@@ -778,6 +830,8 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
cc->iv_gen_ops = &crypt_iv_plain_ops;
else if (strcmp(ivmode, "essiv") == 0)
cc->iv_gen_ops = &crypt_iv_essiv_ops;
+ else if (strcmp(ivmode, "benbi") == 0)
+ cc->iv_gen_ops = &crypt_iv_benbi_ops;
else {
ti->error = "Invalid IV mode";
goto bad2;