diff options
Diffstat (limited to 'drivers/md/dm-crypt.c')
-rw-r--r-- | drivers/md/dm-crypt.c | 342 |
1 files changed, 185 insertions, 157 deletions
diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c index 3bdbb611570..368e8e98f70 100644 --- a/drivers/md/dm-crypt.c +++ b/drivers/md/dm-crypt.c @@ -107,11 +107,10 @@ struct crypt_config { struct workqueue_struct *io_queue; struct workqueue_struct *crypt_queue; - /* - * crypto related data - */ + char *cipher; + char *cipher_mode; + struct crypt_iv_operations *iv_gen_ops; - char *iv_mode; union { struct iv_essiv_private essiv; struct iv_benbi_private benbi; @@ -135,8 +134,6 @@ struct crypt_config { unsigned int dmreq_start; struct ablkcipher_request *req; - char cipher[CRYPTO_MAX_ALG_NAME]; - char chainmode[CRYPTO_MAX_ALG_NAME]; struct crypto_ablkcipher *tfm; unsigned long flags; unsigned int key_size; @@ -999,82 +996,135 @@ static int crypt_wipe_key(struct crypt_config *cc) return crypto_ablkcipher_setkey(cc->tfm, cc->key, cc->key_size); } -/* - * Construct an encryption mapping: - * <cipher> <key> <iv_offset> <dev_path> <start> - */ -static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) +static void crypt_dtr(struct dm_target *ti) { - struct crypt_config *cc; - struct crypto_ablkcipher *tfm; - char *tmp; - char *cipher; - char *chainmode; - char *ivmode; - char *ivopts; - unsigned int key_size; - unsigned long long tmpll; + struct crypt_config *cc = ti->private; - if (argc != 5) { - ti->error = "Not enough arguments"; + ti->private = NULL; + + if (!cc) + return; + + if (cc->io_queue) + destroy_workqueue(cc->io_queue); + if (cc->crypt_queue) + destroy_workqueue(cc->crypt_queue); + + if (cc->bs) + bioset_free(cc->bs); + + if (cc->page_pool) + mempool_destroy(cc->page_pool); + if (cc->req_pool) + mempool_destroy(cc->req_pool); + if (cc->io_pool) + mempool_destroy(cc->io_pool); + + 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); + + kzfree(cc->cipher); + kzfree(cc->cipher_mode); + + /* Must zero key material before freeing */ + kzfree(cc); +} + +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 *cipher_api = NULL; + int ret = -EINVAL; + + /* Convert to crypto api definition? */ + if (strchr(cipher_in, '(')) { + ti->error = "Bad cipher specification"; return -EINVAL; } - tmp = argv[0]; + /* + * Legacy dm-crypt cipher specification + * cipher-mode-iv:ivopts + */ + tmp = cipher_in; cipher = strsep(&tmp, "-"); + + 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, ":"); if (tmp) - DMWARN("Unexpected additional cipher options"); - - key_size = strlen(argv[1]) >> 1; - - cc = kzalloc(sizeof(*cc) + key_size * sizeof(u8), GFP_KERNEL); - if (cc == NULL) { - ti->error = - "Cannot allocate transparent encryption context"; - return -ENOMEM; - } + DMWARN("Ignoring unexpected additional cipher options"); - /* Compatibility mode for old dm-crypt cipher strings */ - if (!chainmode || (strcmp(chainmode, "plain") == 0 && !ivmode)) { + /* Compatibility mode for old dm-crypt mappings */ + if (!chainmode || (!strcmp(chainmode, "plain") && !ivmode)) { + kfree(cc->cipher_mode); + cc->cipher_mode = kstrdup("cbc-plain", GFP_KERNEL); chainmode = "cbc"; ivmode = "plain"; } if (strcmp(chainmode, "ecb") && !ivmode) { - ti->error = "This chaining mode requires an IV mechanism"; - goto bad_cipher; + ti->error = "IV mechanism required"; + return -EINVAL; } - if (snprintf(cc->cipher, CRYPTO_MAX_ALG_NAME, "%s(%s)", - chainmode, cipher) >= CRYPTO_MAX_ALG_NAME) { - ti->error = "Chain mode + cipher name is too long"; - goto bad_cipher; + cipher_api = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL); + if (!cipher_api) + goto bad_mem; + + ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME, + "%s(%s)", chainmode, cipher); + if (ret < 0) { + kfree(cipher_api); + goto bad_mem; } - tfm = crypto_alloc_ablkcipher(cc->cipher, 0, 0); - if (IS_ERR(tfm)) { + /* 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_cipher; + goto bad; } - strcpy(cc->cipher, cipher); - strcpy(cc->chainmode, chainmode); - cc->tfm = tfm; - - if (crypt_set_key(cc, argv[1]) < 0) { + /* Initialize and set key */ + ret = crypt_set_key(cc, key); + if (ret < 0) { ti->error = "Error decoding and setting key"; - goto bad_ivmode; + goto bad; } - /* - * Choose ivmode. Valid modes: "plain", "essiv:<esshash>", "benbi". - * See comments at iv code - */ + /* Initialize IV */ + cc->iv_size = crypto_ablkcipher_ivsize(cc->tfm); + if (cc->iv_size) + /* at least a 64 bit sector number should fit in our buffer */ + cc->iv_size = max(cc->iv_size, + (unsigned int)(sizeof(u64) / sizeof(u8))); + else if (ivmode) { + DMWARN("Selected cipher does not support IVs"); + ivmode = NULL; + } + /* Choose ivmode, see comments at iv code. */ if (ivmode == NULL) cc->iv_gen_ops = NULL; else if (strcmp(ivmode, "plain") == 0) @@ -1088,159 +1138,138 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) else if (strcmp(ivmode, "null") == 0) cc->iv_gen_ops = &crypt_iv_null_ops; else { + ret = -EINVAL; ti->error = "Invalid IV mode"; - goto bad_ivmode; + goto bad; } - if (cc->iv_gen_ops && cc->iv_gen_ops->ctr && - cc->iv_gen_ops->ctr(cc, ti, ivopts) < 0) - goto bad_ivmode; - - if (cc->iv_gen_ops && cc->iv_gen_ops->init && - cc->iv_gen_ops->init(cc) < 0) { - ti->error = "Error initialising IV"; - goto bad_slab_pool; + /* Allocate IV */ + if (cc->iv_gen_ops && cc->iv_gen_ops->ctr) { + ret = cc->iv_gen_ops->ctr(cc, ti, ivopts); + if (ret < 0) { + ti->error = "Error creating IV"; + goto bad; + } } - cc->iv_size = crypto_ablkcipher_ivsize(tfm); - if (cc->iv_size) - /* at least a 64 bit sector number should fit in our buffer */ - cc->iv_size = max(cc->iv_size, - (unsigned int)(sizeof(u64) / sizeof(u8))); - else { - if (cc->iv_gen_ops) { - DMWARN("Selected cipher does not support IVs"); - if (cc->iv_gen_ops->dtr) - cc->iv_gen_ops->dtr(cc); - cc->iv_gen_ops = NULL; + /* Initialize IV (set keys for ESSIV etc) */ + if (cc->iv_gen_ops && cc->iv_gen_ops->init) { + ret = cc->iv_gen_ops->init(cc); + if (ret < 0) { + ti->error = "Error initialising IV"; + goto bad; } } + ret = 0; +bad: + kfree(cipher_api); + return ret; + +bad_mem: + ti->error = "Cannot allocate cipher strings"; + return -ENOMEM; +} + +/* + * Construct an encryption mapping: + * <cipher> <key> <iv_offset> <dev_path> <start> + */ +static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) +{ + struct crypt_config *cc; + unsigned int key_size; + unsigned long long tmpll; + int ret; + + if (argc != 5) { + ti->error = "Not enough arguments"; + return -EINVAL; + } + + key_size = strlen(argv[1]) >> 1; + + cc = kzalloc(sizeof(*cc) + key_size * sizeof(u8), GFP_KERNEL); + if (!cc) { + ti->error = "Cannot allocate encryption context"; + return -ENOMEM; + } + + ti->private = cc; + ret = crypt_ctr_cipher(ti, argv[0], argv[1]); + if (ret < 0) + goto bad; + + ret = -ENOMEM; cc->io_pool = mempool_create_slab_pool(MIN_IOS, _crypt_io_pool); if (!cc->io_pool) { ti->error = "Cannot allocate crypt io mempool"; - goto bad_slab_pool; + goto bad; } cc->dmreq_start = sizeof(struct ablkcipher_request); - cc->dmreq_start += crypto_ablkcipher_reqsize(tfm); + cc->dmreq_start += crypto_ablkcipher_reqsize(cc->tfm); cc->dmreq_start = ALIGN(cc->dmreq_start, crypto_tfm_ctx_alignment()); - cc->dmreq_start += crypto_ablkcipher_alignmask(tfm) & + cc->dmreq_start += crypto_ablkcipher_alignmask(cc->tfm) & ~(crypto_tfm_ctx_alignment() - 1); cc->req_pool = mempool_create_kmalloc_pool(MIN_IOS, cc->dmreq_start + sizeof(struct dm_crypt_request) + cc->iv_size); if (!cc->req_pool) { ti->error = "Cannot allocate crypt request mempool"; - goto bad_req_pool; + goto bad; } cc->req = NULL; cc->page_pool = mempool_create_page_pool(MIN_POOL_PAGES, 0); if (!cc->page_pool) { ti->error = "Cannot allocate page mempool"; - goto bad_page_pool; + goto bad; } cc->bs = bioset_create(MIN_IOS, 0); if (!cc->bs) { ti->error = "Cannot allocate crypt bioset"; - goto bad_bs; + goto bad; } + ret = -EINVAL; if (sscanf(argv[2], "%llu", &tmpll) != 1) { ti->error = "Invalid iv_offset sector"; - goto bad_device; + goto bad; } cc->iv_offset = tmpll; - if (sscanf(argv[4], "%llu", &tmpll) != 1) { - ti->error = "Invalid device sector"; - goto bad_device; - } - cc->start = tmpll; - if (dm_get_device(ti, argv[3], dm_table_get_mode(ti->table), &cc->dev)) { ti->error = "Device lookup failed"; - goto bad_device; + goto bad; } - if (ivmode && cc->iv_gen_ops) { - if (ivopts) - *(ivopts - 1) = ':'; - cc->iv_mode = kmalloc(strlen(ivmode) + 1, GFP_KERNEL); - if (!cc->iv_mode) { - ti->error = "Error kmallocing iv_mode string"; - goto bad_ivmode_string; - } - strcpy(cc->iv_mode, ivmode); - } else - cc->iv_mode = NULL; + if (sscanf(argv[4], "%llu", &tmpll) != 1) { + ti->error = "Invalid device sector"; + goto bad; + } + cc->start = tmpll; + ret = -ENOMEM; cc->io_queue = create_singlethread_workqueue("kcryptd_io"); if (!cc->io_queue) { ti->error = "Couldn't create kcryptd io queue"; - goto bad_io_queue; + goto bad; } cc->crypt_queue = create_singlethread_workqueue("kcryptd"); if (!cc->crypt_queue) { ti->error = "Couldn't create kcryptd queue"; - goto bad_crypt_queue; + goto bad; } ti->num_flush_requests = 1; - ti->private = cc; return 0; -bad_crypt_queue: - destroy_workqueue(cc->io_queue); -bad_io_queue: - kfree(cc->iv_mode); -bad_ivmode_string: - dm_put_device(ti, cc->dev); -bad_device: - bioset_free(cc->bs); -bad_bs: - mempool_destroy(cc->page_pool); -bad_page_pool: - mempool_destroy(cc->req_pool); -bad_req_pool: - mempool_destroy(cc->io_pool); -bad_slab_pool: - if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) - cc->iv_gen_ops->dtr(cc); -bad_ivmode: - crypto_free_ablkcipher(tfm); -bad_cipher: - /* Must zero key material before freeing */ - kzfree(cc); - return -EINVAL; -} - -static void crypt_dtr(struct dm_target *ti) -{ - struct crypt_config *cc = (struct crypt_config *) ti->private; - - destroy_workqueue(cc->io_queue); - destroy_workqueue(cc->crypt_queue); - - if (cc->req) - mempool_free(cc->req, cc->req_pool); - - bioset_free(cc->bs); - mempool_destroy(cc->page_pool); - mempool_destroy(cc->req_pool); - mempool_destroy(cc->io_pool); - - kfree(cc->iv_mode); - if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) - cc->iv_gen_ops->dtr(cc); - crypto_free_ablkcipher(cc->tfm); - dm_put_device(ti, cc->dev); - - /* Must zero key material before freeing */ - kzfree(cc); +bad: + crypt_dtr(ti); + return ret; } static int crypt_map(struct dm_target *ti, struct bio *bio, @@ -1255,7 +1284,7 @@ static int crypt_map(struct dm_target *ti, struct bio *bio, return DM_MAPIO_REMAPPED; } - io = crypt_io_alloc(ti, bio, bio->bi_sector - ti->begin); + 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); @@ -1268,7 +1297,7 @@ static int crypt_map(struct dm_target *ti, struct bio *bio, static int crypt_status(struct dm_target *ti, status_type_t type, char *result, unsigned int maxlen) { - struct crypt_config *cc = (struct crypt_config *) ti->private; + struct crypt_config *cc = ti->private; unsigned int sz = 0; switch (type) { @@ -1277,11 +1306,10 @@ static int crypt_status(struct dm_target *ti, status_type_t type, break; case STATUSTYPE_TABLE: - if (cc->iv_mode) - DMEMIT("%s-%s-%s ", cc->cipher, cc->chainmode, - cc->iv_mode); + if (cc->cipher_mode) + DMEMIT("%s-%s ", cc->cipher, cc->cipher_mode); else - DMEMIT("%s-%s ", cc->cipher, cc->chainmode); + DMEMIT("%s ", cc->cipher); if (cc->key_size > 0) { if ((maxlen - sz) < ((cc->key_size << 1) + 1)) @@ -1378,7 +1406,7 @@ static int crypt_merge(struct dm_target *ti, struct bvec_merge_data *bvm, return max_size; bvm->bi_bdev = cc->dev->bdev; - bvm->bi_sector = cc->start + bvm->bi_sector - ti->begin; + bvm->bi_sector = cc->start + dm_target_offset(ti, bvm->bi_sector); return min(max_size, q->merge_bvec_fn(q, bvm, biovec)); } |