diff options
Diffstat (limited to 'drivers/md/dm-crypt.c')
-rw-r--r-- | drivers/md/dm-crypt.c | 618 |
1 files changed, 509 insertions, 109 deletions
diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c index d5b0e4c..4e054bd 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, |