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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.c618
1 files changed, 509 insertions, 109 deletions
diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index d5b0e4c0e702..4e054bd91664 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -18,10 +18,14 @@
#include <linux/crypto.h>
#include <linux/workqueue.h>
#include <linux/backing-dev.h>
+#include <linux/percpu.h>
#include <asm/atomic.h>
#include <linux/scatterlist.h>
#include <asm/page.h>
#include <asm/unaligned.h>
+#include <crypto/hash.h>
+#include <crypto/md5.h>
+#include <crypto/algapi.h>
#include <linux/device-mapper.h>
@@ -63,6 +67,7 @@ struct dm_crypt_request {
struct convert_context *ctx;
struct scatterlist sg_in;
struct scatterlist sg_out;
+ sector_t iv_sector;
};
struct crypt_config;
@@ -73,11 +78,13 @@ struct crypt_iv_operations {
void (*dtr)(struct crypt_config *cc);
int (*init)(struct crypt_config *cc);
int (*wipe)(struct crypt_config *cc);
- int (*generator)(struct crypt_config *cc, u8 *iv, sector_t sector);
+ int (*generator)(struct crypt_config *cc, u8 *iv,
+ struct dm_crypt_request *dmreq);
+ int (*post)(struct crypt_config *cc, u8 *iv,
+ struct dm_crypt_request *dmreq);
};
struct iv_essiv_private {
- struct crypto_cipher *tfm;
struct crypto_hash *hash_tfm;
u8 *salt;
};
@@ -86,11 +93,32 @@ struct iv_benbi_private {
int shift;
};
+#define LMK_SEED_SIZE 64 /* hash + 0 */
+struct iv_lmk_private {
+ struct crypto_shash *hash_tfm;
+ u8 *seed;
+};
+
/*
* Crypt: maps a linear range of a block device
* and encrypts / decrypts at the same time.
*/
enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID };
+
+/*
+ * Duplicated per-CPU state for cipher.
+ */
+struct crypt_cpu {
+ struct ablkcipher_request *req;
+ /* ESSIV: struct crypto_cipher *essiv_tfm */
+ void *iv_private;
+ struct crypto_ablkcipher *tfms[0];
+};
+
+/*
+ * The fields in here must be read only after initialization,
+ * changing state should be in crypt_cpu.
+ */
struct crypt_config {
struct dm_dev *dev;
sector_t start;
@@ -108,17 +136,25 @@ struct crypt_config {
struct workqueue_struct *crypt_queue;
char *cipher;
- char *cipher_mode;
+ char *cipher_string;
struct crypt_iv_operations *iv_gen_ops;
union {
struct iv_essiv_private essiv;
struct iv_benbi_private benbi;
+ struct iv_lmk_private lmk;
} iv_gen_private;
sector_t iv_offset;
unsigned int iv_size;
/*
+ * Duplicated per cpu state. Access through
+ * per_cpu_ptr() only.
+ */
+ struct crypt_cpu __percpu *cpu;
+ unsigned tfms_count;
+
+ /*
* Layout of each crypto request:
*
* struct ablkcipher_request
@@ -132,11 +168,10 @@ struct crypt_config {
* correctly aligned.
*/
unsigned int dmreq_start;
- struct ablkcipher_request *req;
- struct crypto_ablkcipher *tfm;
unsigned long flags;
unsigned int key_size;
+ unsigned int key_parts;
u8 key[0];
};
@@ -148,6 +183,20 @@ static struct kmem_cache *_crypt_io_pool;
static void clone_init(struct dm_crypt_io *, struct bio *);
static void kcryptd_queue_crypt(struct dm_crypt_io *io);
+static u8 *iv_of_dmreq(struct crypt_config *cc, struct dm_crypt_request *dmreq);
+
+static struct crypt_cpu *this_crypt_config(struct crypt_config *cc)
+{
+ return this_cpu_ptr(cc->cpu);
+}
+
+/*
+ * Use this to access cipher attributes that are the same for each CPU.
+ */
+static struct crypto_ablkcipher *any_tfm(struct crypt_config *cc)
+{
+ return __this_cpu_ptr(cc->cpu)->tfms[0];
+}
/*
* Different IV generation algorithms:
@@ -168,23 +217,38 @@ static void kcryptd_queue_crypt(struct dm_crypt_io *io);
* null: the initial vector is always zero. Provides compatibility with
* obsolete loop_fish2 devices. Do not use for new devices.
*
+ * lmk: Compatible implementation of the block chaining mode used
+ * by the Loop-AES block device encryption system
+ * designed by Jari Ruusu. See http://loop-aes.sourceforge.net/
+ * It operates on full 512 byte sectors and uses CBC
+ * with an IV derived from the sector number, the data and
+ * optionally extra IV seed.
+ * This means that after decryption the first block
+ * of sector must be tweaked according to decrypted data.
+ * Loop-AES can use three encryption schemes:
+ * version 1: is plain aes-cbc mode
+ * version 2: uses 64 multikey scheme with lmk IV generator
+ * version 3: the same as version 2 with additional IV seed
+ * (it uses 65 keys, last key is used as IV seed)
+ *
* plumb: unimplemented, see:
* http://article.gmane.org/gmane.linux.kernel.device-mapper.dm-crypt/454
*/
-static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv, sector_t sector)
+static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv,
+ struct dm_crypt_request *dmreq)
{
memset(iv, 0, cc->iv_size);
- *(u32 *)iv = cpu_to_le32(sector & 0xffffffff);
+ *(u32 *)iv = cpu_to_le32(dmreq->iv_sector & 0xffffffff);
return 0;
}
static int crypt_iv_plain64_gen(struct crypt_config *cc, u8 *iv,
- sector_t sector)
+ struct dm_crypt_request *dmreq)
{
memset(iv, 0, cc->iv_size);
- *(u64 *)iv = cpu_to_le64(sector);
+ *(u64 *)iv = cpu_to_le64(dmreq->iv_sector);
return 0;
}
@@ -195,7 +259,8 @@ static int crypt_iv_essiv_init(struct crypt_config *cc)
struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv;
struct hash_desc desc;
struct scatterlist sg;
- int err;
+ struct crypto_cipher *essiv_tfm;
+ int err, cpu;
sg_init_one(&sg, cc->key, cc->key_size);
desc.tfm = essiv->hash_tfm;
@@ -205,8 +270,16 @@ static int crypt_iv_essiv_init(struct crypt_config *cc)
if (err)
return err;
- return crypto_cipher_setkey(essiv->tfm, essiv->salt,
+ for_each_possible_cpu(cpu) {
+ essiv_tfm = per_cpu_ptr(cc->cpu, cpu)->iv_private,
+
+ err = crypto_cipher_setkey(essiv_tfm, essiv->salt,
crypto_hash_digestsize(essiv->hash_tfm));
+ if (err)
+ return err;
+ }
+
+ return 0;
}
/* Wipe salt and reset key derived from volume key */
@@ -214,24 +287,76 @@ static int crypt_iv_essiv_wipe(struct crypt_config *cc)
{
struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv;
unsigned salt_size = crypto_hash_digestsize(essiv->hash_tfm);
+ struct crypto_cipher *essiv_tfm;
+ int cpu, r, err = 0;
memset(essiv->salt, 0, salt_size);
- return crypto_cipher_setkey(essiv->tfm, essiv->salt, salt_size);
+ for_each_possible_cpu(cpu) {
+ essiv_tfm = per_cpu_ptr(cc->cpu, cpu)->iv_private;
+ r = crypto_cipher_setkey(essiv_tfm, essiv->salt, salt_size);
+ if (r)
+ err = r;
+ }
+
+ return err;
+}
+
+/* Set up per cpu cipher state */
+static struct crypto_cipher *setup_essiv_cpu(struct crypt_config *cc,
+ struct dm_target *ti,
+ u8 *salt, unsigned saltsize)
+{
+ struct crypto_cipher *essiv_tfm;
+ int err;
+
+ /* Setup the essiv_tfm with the given salt */
+ essiv_tfm = crypto_alloc_cipher(cc->cipher, 0, CRYPTO_ALG_ASYNC);
+ if (IS_ERR(essiv_tfm)) {
+ ti->error = "Error allocating crypto tfm for ESSIV";
+ return essiv_tfm;
+ }
+
+ if (crypto_cipher_blocksize(essiv_tfm) !=
+ crypto_ablkcipher_ivsize(any_tfm(cc))) {
+ ti->error = "Block size of ESSIV cipher does "
+ "not match IV size of block cipher";
+ crypto_free_cipher(essiv_tfm);
+ return ERR_PTR(-EINVAL);
+ }
+
+ err = crypto_cipher_setkey(essiv_tfm, salt, saltsize);
+ if (err) {
+ ti->error = "Failed to set key for ESSIV cipher";
+ crypto_free_cipher(essiv_tfm);
+ return ERR_PTR(err);
+ }
+
+ return essiv_tfm;
}
static void crypt_iv_essiv_dtr(struct crypt_config *cc)
{
+ int cpu;
+ struct crypt_cpu *cpu_cc;
+ struct crypto_cipher *essiv_tfm;
struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv;
- crypto_free_cipher(essiv->tfm);
- essiv->tfm = NULL;
-
crypto_free_hash(essiv->hash_tfm);
essiv->hash_tfm = NULL;
kzfree(essiv->salt);
essiv->salt = NULL;
+
+ for_each_possible_cpu(cpu) {
+ cpu_cc = per_cpu_ptr(cc->cpu, cpu);
+ essiv_tfm = cpu_cc->iv_private;
+
+ if (essiv_tfm)
+ crypto_free_cipher(essiv_tfm);
+
+ cpu_cc->iv_private = NULL;
+ }
}
static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti,
@@ -240,7 +365,7 @@ static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti,
struct crypto_cipher *essiv_tfm = NULL;
struct crypto_hash *hash_tfm = NULL;
u8 *salt = NULL;
- int err;
+ int err, cpu;
if (!opts) {
ti->error = "Digest algorithm missing for ESSIV mode";
@@ -262,48 +387,44 @@ static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti,
goto bad;
}
- /* Allocate essiv_tfm */
- essiv_tfm = crypto_alloc_cipher(cc->cipher, 0, CRYPTO_ALG_ASYNC);
- if (IS_ERR(essiv_tfm)) {
- ti->error = "Error allocating crypto tfm for ESSIV";
- err = PTR_ERR(essiv_tfm);
- goto bad;
- }
- if (crypto_cipher_blocksize(essiv_tfm) !=
- crypto_ablkcipher_ivsize(cc->tfm)) {
- ti->error = "Block size of ESSIV cipher does "
- "not match IV size of block cipher";
- err = -EINVAL;
- goto bad;
- }
-
cc->iv_gen_private.essiv.salt = salt;
- cc->iv_gen_private.essiv.tfm = essiv_tfm;
cc->iv_gen_private.essiv.hash_tfm = hash_tfm;
+ for_each_possible_cpu(cpu) {
+ essiv_tfm = setup_essiv_cpu(cc, ti, salt,
+ crypto_hash_digestsize(hash_tfm));
+ if (IS_ERR(essiv_tfm)) {
+ crypt_iv_essiv_dtr(cc);
+ return PTR_ERR(essiv_tfm);
+ }
+ per_cpu_ptr(cc->cpu, cpu)->iv_private = essiv_tfm;
+ }
+
return 0;
bad:
- if (essiv_tfm && !IS_ERR(essiv_tfm))
- crypto_free_cipher(essiv_tfm);
if (hash_tfm && !IS_ERR(hash_tfm))
crypto_free_hash(hash_tfm);
kfree(salt);
return err;
}
-static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv, sector_t sector)
+static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv,
+ struct dm_crypt_request *dmreq)
{
+ struct crypto_cipher *essiv_tfm = this_crypt_config(cc)->iv_private;
+
memset(iv, 0, cc->iv_size);
- *(u64 *)iv = cpu_to_le64(sector);
- crypto_cipher_encrypt_one(cc->iv_gen_private.essiv.tfm, iv, iv);
+ *(u64 *)iv = cpu_to_le64(dmreq->iv_sector);
+ crypto_cipher_encrypt_one(essiv_tfm, iv, iv);
+
return 0;
}
static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti,
const char *opts)
{
- unsigned bs = crypto_ablkcipher_blocksize(cc->tfm);
+ unsigned bs = crypto_ablkcipher_blocksize(any_tfm(cc));
int log = ilog2(bs);
/* we need to calculate how far we must shift the sector count
@@ -328,25 +449,177 @@ 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)
+static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv,
+ struct dm_crypt_request *dmreq)
{
__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);
+ val = cpu_to_be64(((u64)dmreq->iv_sector << cc->iv_gen_private.benbi.shift) + 1);
put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64)));
return 0;
}
-static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv, sector_t sector)
+static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv,
+ struct dm_crypt_request *dmreq)
{
memset(iv, 0, cc->iv_size);
return 0;
}
+static void crypt_iv_lmk_dtr(struct crypt_config *cc)
+{
+ struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
+
+ if (lmk->hash_tfm && !IS_ERR(lmk->hash_tfm))
+ crypto_free_shash(lmk->hash_tfm);
+ lmk->hash_tfm = NULL;
+
+ kzfree(lmk->seed);
+ lmk->seed = NULL;
+}
+
+static int crypt_iv_lmk_ctr(struct crypt_config *cc, struct dm_target *ti,
+ const char *opts)
+{
+ struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
+
+ lmk->hash_tfm = crypto_alloc_shash("md5", 0, 0);
+ if (IS_ERR(lmk->hash_tfm)) {
+ ti->error = "Error initializing LMK hash";
+ return PTR_ERR(lmk->hash_tfm);
+ }
+
+ /* No seed in LMK version 2 */
+ if (cc->key_parts == cc->tfms_count) {
+ lmk->seed = NULL;
+ return 0;
+ }
+
+ lmk->seed = kzalloc(LMK_SEED_SIZE, GFP_KERNEL);
+ if (!lmk->seed) {
+ crypt_iv_lmk_dtr(cc);
+ ti->error = "Error kmallocing seed storage in LMK";
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+static int crypt_iv_lmk_init(struct crypt_config *cc)
+{
+ struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
+ int subkey_size = cc->key_size / cc->key_parts;
+
+ /* LMK seed is on the position of LMK_KEYS + 1 key */
+ if (lmk->seed)
+ memcpy(lmk->seed, cc->key + (cc->tfms_count * subkey_size),
+ crypto_shash_digestsize(lmk->hash_tfm));
+
+ return 0;
+}
+
+static int crypt_iv_lmk_wipe(struct crypt_config *cc)
+{
+ struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
+
+ if (lmk->seed)
+ memset(lmk->seed, 0, LMK_SEED_SIZE);
+
+ return 0;
+}
+
+static int crypt_iv_lmk_one(struct crypt_config *cc, u8 *iv,
+ struct dm_crypt_request *dmreq,
+ u8 *data)
+{
+ struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
+ struct {
+ struct shash_desc desc;
+ char ctx[crypto_shash_descsize(lmk->hash_tfm)];
+ } sdesc;
+ struct md5_state md5state;
+ u32 buf[4];
+ int i, r;
+
+ sdesc.desc.tfm = lmk->hash_tfm;
+ sdesc.desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP;
+
+ r = crypto_shash_init(&sdesc.desc);
+ if (r)
+ return r;
+
+ if (lmk->seed) {
+ r = crypto_shash_update(&sdesc.desc, lmk->seed, LMK_SEED_SIZE);
+ if (r)
+ return r;
+ }
+
+ /* Sector is always 512B, block size 16, add data of blocks 1-31 */
+ r = crypto_shash_update(&sdesc.desc, data + 16, 16 * 31);
+ if (r)
+ return r;
+
+ /* Sector is cropped to 56 bits here */
+ buf[0] = cpu_to_le32(dmreq->iv_sector & 0xFFFFFFFF);
+ buf[1] = cpu_to_le32((((u64)dmreq->iv_sector >> 32) & 0x00FFFFFF) | 0x80000000);
+ buf[2] = cpu_to_le32(4024);
+ buf[3] = 0;
+ r = crypto_shash_update(&sdesc.desc, (u8 *)buf, sizeof(buf));
+ if (r)
+ return r;
+
+ /* No MD5 padding here */
+ r = crypto_shash_export(&sdesc.desc, &md5state);
+ if (r)
+ return r;
+
+ for (i = 0; i < MD5_HASH_WORDS; i++)
+ __cpu_to_le32s(&md5state.hash[i]);
+ memcpy(iv, &md5state.hash, cc->iv_size);
+
+ return 0;
+}
+
+static int crypt_iv_lmk_gen(struct crypt_config *cc, u8 *iv,
+ struct dm_crypt_request *dmreq)
+{
+ u8 *src;
+ int r = 0;
+
+ if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) {
+ src = kmap_atomic(sg_page(&dmreq->sg_in), KM_USER0);
+ r = crypt_iv_lmk_one(cc, iv, dmreq, src + dmreq->sg_in.offset);
+ kunmap_atomic(src, KM_USER0);
+ } else
+ memset(iv, 0, cc->iv_size);
+
+ return r;
+}
+
+static int crypt_iv_lmk_post(struct crypt_config *cc, u8 *iv,
+ struct dm_crypt_request *dmreq)
+{
+ u8 *dst;
+ int r;
+
+ if (bio_data_dir(dmreq->ctx->bio_in) == WRITE)
+ return 0;
+
+ dst = kmap_atomic(sg_page(&dmreq->sg_out), KM_USER0);
+ r = crypt_iv_lmk_one(cc, iv, dmreq, dst + dmreq->sg_out.offset);
+
+ /* Tweak the first block of plaintext sector */
+ if (!r)
+ crypto_xor(dst + dmreq->sg_out.offset, iv, cc->iv_size);
+
+ kunmap_atomic(dst, KM_USER0);
+ return r;
+}
+
static struct crypt_iv_operations crypt_iv_plain_ops = {
.generator = crypt_iv_plain_gen
};
@@ -373,6 +646,15 @@ static struct crypt_iv_operations crypt_iv_null_ops = {
.generator = crypt_iv_null_gen
};
+static struct crypt_iv_operations crypt_iv_lmk_ops = {
+ .ctr = crypt_iv_lmk_ctr,
+ .dtr = crypt_iv_lmk_dtr,
+ .init = crypt_iv_lmk_init,
+ .wipe = crypt_iv_lmk_wipe,
+ .generator = crypt_iv_lmk_gen,
+ .post = crypt_iv_lmk_post
+};
+
static void crypt_convert_init(struct crypt_config *cc,
struct convert_context *ctx,
struct bio *bio_out, struct bio *bio_in,
@@ -400,6 +682,13 @@ static struct ablkcipher_request *req_of_dmreq(struct crypt_config *cc,
return (struct ablkcipher_request *)((char *)dmreq - cc->dmreq_start);
}
+static u8 *iv_of_dmreq(struct crypt_config *cc,
+ struct dm_crypt_request *dmreq)
+{
+ return (u8 *)ALIGN((unsigned long)(dmreq + 1),
+ crypto_ablkcipher_alignmask(any_tfm(cc)) + 1);
+}
+
static int crypt_convert_block(struct crypt_config *cc,
struct convert_context *ctx,
struct ablkcipher_request *req)
@@ -411,9 +700,9 @@ static int crypt_convert_block(struct crypt_config *cc,
int r = 0;
dmreq = dmreq_of_req(cc, req);
- iv = (u8 *)ALIGN((unsigned long)(dmreq + 1),
- crypto_ablkcipher_alignmask(cc->tfm) + 1);
+ iv = iv_of_dmreq(cc, dmreq);
+ dmreq->iv_sector = ctx->sector;
dmreq->ctx = ctx;
sg_init_table(&dmreq->sg_in, 1);
sg_set_page(&dmreq->sg_in, bv_in->bv_page, 1 << SECTOR_SHIFT,
@@ -436,7 +725,7 @@ static int crypt_convert_block(struct crypt_config *cc,
}
if (cc->iv_gen_ops) {
- r = cc->iv_gen_ops->generator(cc, iv, ctx->sector);
+ r = cc->iv_gen_ops->generator(cc, iv, dmreq);
if (r < 0)
return r;
}
@@ -449,21 +738,28 @@ static int crypt_convert_block(struct crypt_config *cc,
else
r = crypto_ablkcipher_decrypt(req);
+ if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post)
+ r = cc->iv_gen_ops->post(cc, iv, dmreq);
+
return r;
}
static void kcryptd_async_done(struct crypto_async_request *async_req,
int error);
+
static void crypt_alloc_req(struct crypt_config *cc,
struct convert_context *ctx)
{
- if (!cc->req)
- cc->req = mempool_alloc(cc->req_pool, GFP_NOIO);
- ablkcipher_request_set_tfm(cc->req, cc->tfm);
- ablkcipher_request_set_callback(cc->req, CRYPTO_TFM_REQ_MAY_BACKLOG |
- CRYPTO_TFM_REQ_MAY_SLEEP,
- kcryptd_async_done,
- dmreq_of_req(cc, cc->req));
+ struct crypt_cpu *this_cc = this_crypt_config(cc);
+ unsigned key_index = ctx->sector & (cc->tfms_count - 1);
+
+ if (!this_cc->req)
+ this_cc->req = mempool_alloc(cc->req_pool, GFP_NOIO);
+
+ ablkcipher_request_set_tfm(this_cc->req, this_cc->tfms[key_index]);
+ ablkcipher_request_set_callback(this_cc->req,
+ CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
+ kcryptd_async_done, dmreq_of_req(cc, this_cc->req));
}
/*
@@ -472,6 +768,7 @@ static void crypt_alloc_req(struct crypt_config *cc,
static int crypt_convert(struct crypt_config *cc,
struct convert_context *ctx)
{
+ struct crypt_cpu *this_cc = this_crypt_config(cc);
int r;
atomic_set(&ctx->pending, 1);
@@ -483,7 +780,7 @@ static int crypt_convert(struct crypt_config *cc,
atomic_inc(&ctx->pending);
- r = crypt_convert_block(cc, ctx, cc->req);
+ r = crypt_convert_block(cc, ctx, this_cc->req);
switch (r) {
/* async */
@@ -492,7 +789,7 @@ static int crypt_convert(struct crypt_config *cc,
INIT_COMPLETION(ctx->restart);
/* fall through*/
case -EINPROGRESS:
- cc->req = NULL;
+ this_cc->req = NULL;
ctx->sector++;
continue;
@@ -651,6 +948,9 @@ static void crypt_dec_pending(struct dm_crypt_io *io)
* They must be separated as otherwise the final stages could be
* starved by new requests which can block in the first stages due
* to memory allocation.
+ *
+ * The work is done per CPU global for all dm-crypt instances.
+ * They should not depend on each other and do not block.
*/
static void crypt_endio(struct bio *clone, int error)
{
@@ -691,26 +991,30 @@ static void clone_init(struct dm_crypt_io *io, struct bio *clone)
clone->bi_destructor = dm_crypt_bio_destructor;
}
-static void kcryptd_io_read(struct dm_crypt_io *io)
+static void kcryptd_unplug(struct crypt_config *cc)
+{
+ blk_unplug(bdev_get_queue(cc->dev->bdev));
+}
+
+static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp)
{
struct crypt_config *cc = io->target->private;
struct bio *base_bio = io->base_bio;
struct bio *clone;
- crypt_inc_pending(io);
-
/*
* The block layer might modify the bvec array, so always
* copy the required bvecs because we need the original
* one in order to decrypt the whole bio data *afterwards*.
*/
- clone = bio_alloc_bioset(GFP_NOIO, bio_segments(base_bio), cc->bs);
- if (unlikely(!clone)) {
- io->error = -ENOMEM;
- crypt_dec_pending(io);
- return;
+ clone = bio_alloc_bioset(gfp, bio_segments(base_bio), cc->bs);
+ if (!clone) {
+ kcryptd_unplug(cc);
+ return 1;
}
+ crypt_inc_pending(io);
+
clone_init(io, clone);
clone->bi_idx = 0;
clone->bi_vcnt = bio_segments(base_bio);
@@ -720,6 +1024,7 @@ static void kcryptd_io_read(struct dm_crypt_io *io)
sizeof(struct bio_vec) * clone->bi_vcnt);
generic_make_request(clone);
+ return 0;
}
static void kcryptd_io_write(struct dm_crypt_io *io)
@@ -732,9 +1037,12 @@ static void kcryptd_io(struct work_struct *work)
{
struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
- if (bio_data_dir(io->base_bio) == READ)
- kcryptd_io_read(io);
- else
+ if (bio_data_dir(io->base_bio) == READ) {
+ crypt_inc_pending(io);
+ if (kcryptd_io_read(io, GFP_NOIO))
+ io->error = -ENOMEM;
+ crypt_dec_pending(io);
+ } else
kcryptd_io_write(io);
}
@@ -901,6 +1209,9 @@ static void kcryptd_async_done(struct crypto_async_request *async_req,
return;
}
+ if (!error && cc->iv_gen_ops && cc->iv_gen_ops->post)
+ error = cc->iv_gen_ops->post(cc, iv_of_dmreq(cc, dmreq), dmreq);
+
mempool_free(req_of_dmreq(cc, dmreq), cc->req_pool);
if (!atomic_dec_and_test(&ctx->pending))
@@ -971,34 +1282,84 @@ static void crypt_encode_key(char *hex, u8 *key, unsigned int size)
}
}
-static int crypt_set_key(struct crypt_config *cc, char *key)
+static void crypt_free_tfms(struct crypt_config *cc, int cpu)
{
- unsigned key_size = strlen(key) >> 1;
+ struct crypt_cpu *cpu_cc = per_cpu_ptr(cc->cpu, cpu);
+ unsigned i;
- if (cc->key_size && cc->key_size != key_size)
+ for (i = 0; i < cc->tfms_count; i++)
+ if (cpu_cc->tfms[i] && !IS_ERR(cpu_cc->tfms[i])) {
+ crypto_free_ablkcipher(cpu_cc->tfms[i]);
+ cpu_cc->tfms[i] = NULL;
+ }
+}
+
+static int crypt_alloc_tfms(struct crypt_config *cc, int cpu, char *ciphermode)
+{
+ struct crypt_cpu *cpu_cc = per_cpu_ptr(cc->cpu, cpu);
+ unsigned i;
+ int err;
+
+ for (i = 0; i < cc->tfms_count; i++) {
+ cpu_cc->tfms[i] = crypto_alloc_ablkcipher(ciphermode, 0, 0);
+ if (IS_ERR(cpu_cc->tfms[i])) {
+ err = PTR_ERR(cpu_cc->tfms[i]);
+ crypt_free_tfms(cc, cpu);
+ return err;
+ }
+ }
+
+ return 0;
+}
+
+static int crypt_setkey_allcpus(struct crypt_config *cc)
+{
+ unsigned subkey_size = cc->key_size >> ilog2(cc->tfms_count);
+ int cpu, err = 0, i, r;
+
+ for_each_possible_cpu(cpu) {
+ for (i = 0; i < cc->tfms_count; i++) {
+ r = crypto_ablkcipher_setkey(per_cpu_ptr(cc->cpu, cpu)->tfms[i],
+ cc->key + (i * subkey_size), subkey_size);
+ if (r)
+ err = r;
+ }
+ }
+
+ return err;
+}
+
+static int crypt_set_key(struct crypt_config *cc, char *key)
+{
+ /* The key size may not be changed. */
+ if (cc->key_size != (strlen(key) >> 1))
return -EINVAL;
- cc->key_size = key_size; /* initial settings */
+ /* Hyphen (which gives a key_size of zero) means there is no key. */
+ if (!cc->key_size && strcmp(key, "-"))
+ return -EINVAL;
- if ((!key_size && strcmp(key, "-")) ||
- (key_size && crypt_decode_key(cc->key, key, key_size) < 0))
+ if (cc->key_size && crypt_decode_key(cc->key, key, cc->key_size) < 0)
return -EINVAL;
set_bit(DM_CRYPT_KEY_VALID, &cc->flags);
- return crypto_ablkcipher_setkey(cc->tfm, cc->key, cc->key_size);
+ return crypt_setkey_allcpus(cc);
}
static int crypt_wipe_key(struct crypt_config *cc)
{
clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);
memset(&cc->key, 0, cc->key_size * sizeof(u8));
- return crypto_ablkcipher_setkey(cc->tfm, cc->key, cc->key_size);
+
+ return crypt_setkey_allcpus(cc);
}
static void crypt_dtr(struct dm_target *ti)
{
struct crypt_config *cc = ti->private;
+ struct crypt_cpu *cpu_cc;
+ int cpu;
ti->private = NULL;
@@ -1010,6 +1371,14 @@ static void crypt_dtr(struct dm_target *ti)
if (cc->crypt_queue)
destroy_workqueue(cc->crypt_queue);
+ if (cc->cpu)
+ for_each_possible_cpu(cpu) {
+ cpu_cc = per_cpu_ptr(cc->cpu, cpu);
+ if (cpu_cc->req)
+ mempool_free(cpu_cc->req, cc->req_pool);
+ crypt_free_tfms(cc, cpu);
+ }
+
if (cc->bs)
bioset_free(cc->bs);
@@ -1023,14 +1392,14 @@ static void crypt_dtr(struct dm_target *ti)
if (cc->iv_gen_ops && cc->iv_gen_ops->dtr)
cc->iv_gen_ops->dtr(cc);
- if (cc->tfm && !IS_ERR(cc->tfm))
- crypto_free_ablkcipher(cc->tfm);
-
if (cc->dev)
dm_put_device(ti, cc->dev);
+ if (cc->cpu)
+ free_percpu(cc->cpu);
+
kzfree(cc->cipher);
- kzfree(cc->cipher_mode);
+ kzfree(cc->cipher_string);
/* Must zero key material before freeing */
kzfree(cc);
@@ -1040,9 +1409,9 @@ static int crypt_ctr_cipher(struct dm_target *ti,
char *cipher_in, char *key)
{
struct crypt_config *cc = ti->private;
- char *tmp, *cipher, *chainmode, *ivmode, *ivopts;
+ char *tmp, *cipher, *chainmode, *ivmode, *ivopts, *keycount;
char *cipher_api = NULL;
- int ret = -EINVAL;
+ int cpu, ret = -EINVAL;
/* Convert to crypto api definition? */
if (strchr(cipher_in, '(')) {
@@ -1050,23 +1419,31 @@ static int crypt_ctr_cipher(struct dm_target *ti,
return -EINVAL;
}
+ cc->cipher_string = kstrdup(cipher_in, GFP_KERNEL);
+ if (!cc->cipher_string)
+ goto bad_mem;
+
/*
* Legacy dm-crypt cipher specification
- * cipher-mode-iv:ivopts
+ * cipher[:keycount]-mode-iv:ivopts
*/
tmp = cipher_in;
- cipher = strsep(&tmp, "-");
+ keycount = strsep(&tmp, "-");
+ cipher = strsep(&keycount, ":");
+
+ if (!keycount)
+ cc->tfms_count = 1;
+ else if (sscanf(keycount, "%u", &cc->tfms_count) != 1 ||
+ !is_power_of_2(cc->tfms_count)) {
+ ti->error = "Bad cipher key count specification";
+ return -EINVAL;
+ }
+ cc->key_parts = cc->tfms_count;
cc->cipher = kstrdup(cipher, GFP_KERNEL);
if (!cc->cipher)
goto bad_mem;
- if (tmp) {
- cc->cipher_mode = kstrdup(tmp, GFP_KERNEL);
- if (!cc->cipher_mode)
- goto bad_mem;
- }
-
chainmode = strsep(&tmp, "-");
ivopts = strsep(&tmp, "-");
ivmode = strsep(&ivopts, ":");
@@ -1074,10 +1451,19 @@ static int crypt_ctr_cipher(struct dm_target *ti,
if (tmp)
DMWARN("Ignoring unexpected additional cipher options");
- /* Compatibility mode for old dm-crypt mappings */
+ cc->cpu = __alloc_percpu(sizeof(*(cc->cpu)) +
+ cc->tfms_count * sizeof(*(cc->cpu->tfms)),
+ __alignof__(struct crypt_cpu));
+ if (!cc->cpu) {
+ ti->error = "Cannot allocate per cpu state";
+ goto bad_mem;
+ }
+
+ /*
+ * For compatibility with the original dm-crypt mapping format, if
+ * only the cipher name is supplied, use cbc-plain.
+ */
if (!chainmode || (!strcmp(chainmode, "plain") && !ivmode)) {
- kfree(cc->cipher_mode);
- cc->cipher_mode = kstrdup("cbc-plain", GFP_KERNEL);
chainmode = "cbc";
ivmode = "plain";
}
@@ -1099,11 +1485,12 @@ static int crypt_ctr_cipher(struct dm_target *ti,
}
/* Allocate cipher */
- cc->tfm = crypto_alloc_ablkcipher(cipher_api, 0, 0);
- if (IS_ERR(cc->tfm)) {
- ret = PTR_ERR(cc->tfm);
- ti->error = "Error allocating crypto tfm";
- goto bad;
+ for_each_possible_cpu(cpu) {
+ ret = crypt_alloc_tfms(cc, cpu, cipher_api);
+ if (ret < 0) {
+ ti->error = "Error allocating crypto tfm";
+ goto bad;
+ }
}
/* Initialize and set key */
@@ -1114,7 +1501,7 @@ static int crypt_ctr_cipher(struct dm_target *ti,
}
/* Initialize IV */
- cc->iv_size = crypto_ablkcipher_ivsize(cc->tfm);
+ cc->iv_size = crypto_ablkcipher_ivsize(any_tfm(cc));
if (cc->iv_size)
/* at least a 64 bit sector number should fit in our buffer */
cc->iv_size = max(cc->iv_size,
@@ -1137,7 +1524,15 @@ static int crypt_ctr_cipher(struct dm_target *ti,
cc->iv_gen_ops = &crypt_iv_benbi_ops;
else if (strcmp(ivmode, "null") == 0)
cc->iv_gen_ops = &crypt_iv_null_ops;
- else {
+ else if (strcmp(ivmode, "lmk") == 0) {
+ cc->iv_gen_ops = &crypt_iv_lmk_ops;
+ /* Version 2 and 3 is recognised according
+ * to length of provided multi-key string.
+ * If present (version 3), last key is used as IV seed.
+ */
+ if (cc->key_size % cc->key_parts)
+ cc->key_parts++;
+ } else {
ret = -EINVAL;
ti->error = "Invalid IV mode";
goto bad;
@@ -1194,6 +1589,7 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
ti->error = "Cannot allocate encryption context";
return -ENOMEM;
}
+ cc->key_size = key_size;
ti->private = cc;
ret = crypt_ctr_cipher(ti, argv[0], argv[1]);
@@ -1208,9 +1604,9 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
}
cc->dmreq_start = sizeof(struct ablkcipher_request);
- cc->dmreq_start += crypto_ablkcipher_reqsize(cc->tfm);
+ cc->dmreq_start += crypto_ablkcipher_reqsize(any_tfm(cc));
cc->dmreq_start = ALIGN(cc->dmreq_start, crypto_tfm_ctx_alignment());
- cc->dmreq_start += crypto_ablkcipher_alignmask(cc->tfm) &
+ cc->dmreq_start += crypto_ablkcipher_alignmask(any_tfm(cc)) &
~(crypto_tfm_ctx_alignment() - 1);
cc->req_pool = mempool_create_kmalloc_pool(MIN_IOS, cc->dmreq_start +
@@ -1219,7 +1615,6 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
ti->error = "Cannot allocate crypt request mempool";
goto bad;
}
- cc->req = NULL;
cc->page_pool = mempool_create_page_pool(MIN_POOL_PAGES, 0);
if (!cc->page_pool) {
@@ -1252,13 +1647,20 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
cc->start = tmpll;
ret = -ENOMEM;
- cc->io_queue = create_singlethread_workqueue("kcryptd_io");
+ cc->io_queue = alloc_workqueue("kcryptd_io",
+ WQ_NON_REENTRANT|
+ WQ_MEM_RECLAIM,
+ 1);
if (!cc->io_queue) {
ti->error = "Couldn't create kcryptd io queue";
goto bad;
}
- cc->crypt_queue = create_singlethread_workqueue("kcryptd");
+ cc->crypt_queue = alloc_workqueue("kcryptd",
+ WQ_NON_REENTRANT|
+ WQ_CPU_INTENSIVE|
+ WQ_MEM_RECLAIM,
+ 1);
if (!cc->crypt_queue) {
ti->error = "Couldn't create kcryptd queue";
goto bad;
@@ -1286,9 +1688,10 @@ static int crypt_map(struct dm_target *ti, struct bio *bio,
io = crypt_io_alloc(ti, bio, dm_target_offset(ti, bio->bi_sector));
- if (bio_data_dir(io->base_bio) == READ)
- kcryptd_queue_io(io);
- else
+ if (bio_data_dir(io->base_bio) == READ) {
+ if (kcryptd_io_read(io, GFP_NOWAIT))
+ kcryptd_queue_io(io);
+ } else
kcryptd_queue_crypt(io);
return DM_MAPIO_SUBMITTED;
@@ -1306,10 +1709,7 @@ static int crypt_status(struct dm_target *ti, status_type_t type,
break;
case STATUSTYPE_TABLE:
- if (cc->cipher_mode)
- DMEMIT("%s-%s ", cc->cipher, cc->cipher_mode);
- else
- DMEMIT("%s ", cc->cipher);
+ DMEMIT("%s ", cc->cipher_string);
if (cc->key_size > 0) {
if ((maxlen - sz) < ((cc->key_size << 1) + 1))
@@ -1421,7 +1821,7 @@ static int crypt_iterate_devices(struct dm_target *ti,
static struct target_type crypt_target = {
.name = "crypt",
- .version = {1, 7, 0},
+ .version = {1, 10, 0},
.module = THIS_MODULE,
.ctr = crypt_ctr,
.dtr = crypt_dtr,