diff options
Diffstat (limited to 'ANDROID_3.4.5/drivers/md/dm-crypt.c')
| -rw-r--r-- | ANDROID_3.4.5/drivers/md/dm-crypt.c | 1914 |
1 files changed, 0 insertions, 1914 deletions
diff --git a/ANDROID_3.4.5/drivers/md/dm-crypt.c b/ANDROID_3.4.5/drivers/md/dm-crypt.c deleted file mode 100644 index 3f06df59..00000000 --- a/ANDROID_3.4.5/drivers/md/dm-crypt.c +++ /dev/null @@ -1,1914 +0,0 @@ -/* - * Copyright (C) 2003 Christophe Saout <christophe@saout.de> - * Copyright (C) 2004 Clemens Fruhwirth <clemens@endorphin.org> - * Copyright (C) 2006-2009 Red Hat, Inc. All rights reserved. - * - * This file is released under the GPL. - */ - -#include <linux/completion.h> -#include <linux/err.h> -#include <linux/module.h> -#include <linux/init.h> -#include <linux/kernel.h> -#include <linux/bio.h> -#include <linux/blkdev.h> -#include <linux/mempool.h> -#include <linux/slab.h> -#include <linux/crypto.h> -#include <linux/workqueue.h> -#include <linux/backing-dev.h> -#include <linux/percpu.h> -#include <linux/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> - -#define DM_MSG_PREFIX "crypt" - -/* - * context holding the current state of a multi-part conversion - */ -struct convert_context { - struct completion restart; - struct bio *bio_in; - struct bio *bio_out; - unsigned int offset_in; - unsigned int offset_out; - unsigned int idx_in; - unsigned int idx_out; - sector_t sector; - atomic_t pending; -}; - -/* - * per bio private data - */ -struct dm_crypt_io { - struct dm_target *target; - struct bio *base_bio; - struct work_struct work; - - struct convert_context ctx; - - atomic_t pending; - int error; - sector_t sector; - struct dm_crypt_io *base_io; -}; - -struct dm_crypt_request { - struct convert_context *ctx; - struct scatterlist sg_in; - struct scatterlist sg_out; - sector_t iv_sector; -}; - -struct crypt_config; - -struct crypt_iv_operations { - int (*ctr)(struct crypt_config *cc, struct dm_target *ti, - const char *opts); - 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, - struct dm_crypt_request *dmreq); - int (*post)(struct crypt_config *cc, u8 *iv, - struct dm_crypt_request *dmreq); -}; - -struct iv_essiv_private { - struct crypto_hash *hash_tfm; - u8 *salt; -}; - -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; - - /* - * pool for per bio private data, crypto requests and - * encryption requeusts/buffer pages - */ - mempool_t *io_pool; - mempool_t *req_pool; - mempool_t *page_pool; - struct bio_set *bs; - - struct workqueue_struct *io_queue; - struct workqueue_struct *crypt_queue; - - char *cipher; - 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 - * context - * padding - * struct dm_crypt_request - * padding - * IV - * - * The padding is added so that dm_crypt_request and the IV are - * correctly aligned. - */ - unsigned int dmreq_start; - - unsigned long flags; - unsigned int key_size; - unsigned int key_parts; - u8 key[0]; -}; - -#define MIN_IOS 16 -#define MIN_POOL_PAGES 32 - -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: - * - * plain: the initial vector is the 32-bit little-endian version of the sector - * number, padded with zeros if necessary. - * - * plain64: the initial vector is the 64-bit little-endian version of the sector - * number, padded with zeros if necessary. - * - * essiv: "encrypted sector|salt initial vector", the sector number is - * 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) - * - * 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, - struct dm_crypt_request *dmreq) -{ - memset(iv, 0, cc->iv_size); - *(__le32 *)iv = cpu_to_le32(dmreq->iv_sector & 0xffffffff); - - return 0; -} - -static int crypt_iv_plain64_gen(struct crypt_config *cc, u8 *iv, - struct dm_crypt_request *dmreq) -{ - memset(iv, 0, cc->iv_size); - *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector); - - return 0; -} - -/* Initialise ESSIV - compute salt but no local memory allocations */ -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; - struct crypto_cipher *essiv_tfm; - int err, cpu; - - sg_init_one(&sg, cc->key, cc->key_size); - desc.tfm = essiv->hash_tfm; - desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP; - - err = crypto_hash_digest(&desc, &sg, cc->key_size, essiv->salt); - if (err) - return err; - - 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 */ -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); - - 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_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, - const char *opts) -{ - struct crypto_cipher *essiv_tfm = NULL; - struct crypto_hash *hash_tfm = NULL; - u8 *salt = NULL; - int err, cpu; - - if (!opts) { - ti->error = "Digest algorithm missing for ESSIV mode"; - return -EINVAL; - } - - /* Allocate hash algorithm */ - hash_tfm = crypto_alloc_hash(opts, 0, CRYPTO_ALG_ASYNC); - if (IS_ERR(hash_tfm)) { - ti->error = "Error initializing ESSIV hash"; - err = PTR_ERR(hash_tfm); - goto bad; - } - - salt = kzalloc(crypto_hash_digestsize(hash_tfm), GFP_KERNEL); - if (!salt) { - ti->error = "Error kmallocing salt storage in ESSIV"; - err = -ENOMEM; - goto bad; - } - - cc->iv_gen_private.essiv.salt = salt; - 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 (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, - struct dm_crypt_request *dmreq) -{ - struct crypto_cipher *essiv_tfm = this_crypt_config(cc)->iv_private; - - memset(iv, 0, cc->iv_size); - *(__le64 *)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(any_tfm(cc)); - int log = ilog2(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, - struct dm_crypt_request *dmreq) -{ - __be64 val; - - memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */ - - 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, - 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)); - r = crypt_iv_lmk_one(cc, iv, dmreq, src + dmreq->sg_in.offset); - kunmap_atomic(src); - } 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)); - 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); - return r; -} - -static struct crypt_iv_operations crypt_iv_plain_ops = { - .generator = crypt_iv_plain_gen -}; - -static struct crypt_iv_operations crypt_iv_plain64_ops = { - .generator = crypt_iv_plain64_gen -}; - -static struct crypt_iv_operations crypt_iv_essiv_ops = { - .ctr = crypt_iv_essiv_ctr, - .dtr = crypt_iv_essiv_dtr, - .init = crypt_iv_essiv_init, - .wipe = crypt_iv_essiv_wipe, - .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 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, - sector_t sector) -{ - ctx->bio_in = bio_in; - ctx->bio_out = bio_out; - ctx->offset_in = 0; - ctx->offset_out = 0; - ctx->idx_in = bio_in ? bio_in->bi_idx : 0; - ctx->idx_out = bio_out ? bio_out->bi_idx : 0; - ctx->sector = sector + cc->iv_offset; - init_completion(&ctx->restart); -} - -static struct dm_crypt_request *dmreq_of_req(struct crypt_config *cc, - struct ablkcipher_request *req) -{ - return (struct dm_crypt_request *)((char *)req + cc->dmreq_start); -} - -static struct ablkcipher_request *req_of_dmreq(struct crypt_config *cc, - struct dm_crypt_request *dmreq) -{ - 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) -{ - struct bio_vec *bv_in = bio_iovec_idx(ctx->bio_in, ctx->idx_in); - struct bio_vec *bv_out = bio_iovec_idx(ctx->bio_out, ctx->idx_out); - struct dm_crypt_request *dmreq; - u8 *iv; - int r = 0; - - dmreq = dmreq_of_req(cc, req); - 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, - bv_in->bv_offset + ctx->offset_in); - - sg_init_table(&dmreq->sg_out, 1); - sg_set_page(&dmreq->sg_out, bv_out->bv_page, 1 << SECTOR_SHIFT, - bv_out->bv_offset + ctx->offset_out); - - ctx->offset_in += 1 << SECTOR_SHIFT; - if (ctx->offset_in >= bv_in->bv_len) { - ctx->offset_in = 0; - ctx->idx_in++; - } - - ctx->offset_out += 1 << SECTOR_SHIFT; - if (ctx->offset_out >= bv_out->bv_len) { - ctx->offset_out = 0; - ctx->idx_out++; - } - - if (cc->iv_gen_ops) { - r = cc->iv_gen_ops->generator(cc, iv, dmreq); - if (r < 0) - return r; - } - - ablkcipher_request_set_crypt(req, &dmreq->sg_in, &dmreq->sg_out, - 1 << SECTOR_SHIFT, iv); - - if (bio_data_dir(ctx->bio_in) == WRITE) - r = crypto_ablkcipher_encrypt(req); - 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) -{ - 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)); -} - -/* - * Encrypt / decrypt data from one bio to another one (can be the same one) - */ -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); - - while(ctx->idx_in < ctx->bio_in->bi_vcnt && - ctx->idx_out < ctx->bio_out->bi_vcnt) { - - crypt_alloc_req(cc, ctx); - - atomic_inc(&ctx->pending); - - r = crypt_convert_block(cc, ctx, this_cc->req); - - switch (r) { - /* async */ - case -EBUSY: - wait_for_completion(&ctx->restart); - INIT_COMPLETION(ctx->restart); - /* fall through*/ - case -EINPROGRESS: - this_cc->req = NULL; - ctx->sector++; - continue; - - /* sync */ - case 0: - atomic_dec(&ctx->pending); - ctx->sector++; - cond_resched(); - continue; - - /* error */ - default: - atomic_dec(&ctx->pending); - return r; - } - } - - return 0; -} - -static void dm_crypt_bio_destructor(struct bio *bio) -{ - struct dm_crypt_io *io = bio->bi_private; - struct crypt_config *cc = io->target->private; - - bio_free(bio, cc->bs); -} - -/* - * Generate a new unfragmented bio with the given size - * This should never violate the device limitations - * May return a smaller bio when running out of pages, indicated by - * *out_of_pages set to 1. - */ -static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned size, - unsigned *out_of_pages) -{ - struct crypt_config *cc = io->target->private; - struct bio *clone; - unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; - gfp_t gfp_mask = GFP_NOIO | __GFP_HIGHMEM; - unsigned i, len; - struct page *page; - - clone = bio_alloc_bioset(GFP_NOIO, nr_iovecs, cc->bs); - if (!clone) - return NULL; - - clone_init(io, clone); - *out_of_pages = 0; - - for (i = 0; i < nr_iovecs; i++) { - page = mempool_alloc(cc->page_pool, gfp_mask); - if (!page) { - *out_of_pages = 1; - break; - } - - /* - * If additional pages cannot be allocated without waiting, - * return a partially-allocated bio. The caller will then try - * to allocate more bios while submitting this partial bio. - */ - gfp_mask = (gfp_mask | __GFP_NOWARN) & ~__GFP_WAIT; - - len = (size > PAGE_SIZE) ? PAGE_SIZE : size; - - if (!bio_add_page(clone, page, len, 0)) { - mempool_free(page, cc->page_pool); - break; - } - - size -= len; - } - - if (!clone->bi_size) { - bio_put(clone); - return NULL; - } - - return clone; -} - -static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone) -{ - unsigned int i; - struct bio_vec *bv; - - for (i = 0; i < clone->bi_vcnt; i++) { - bv = bio_iovec_idx(clone, i); - BUG_ON(!bv->bv_page); - mempool_free(bv->bv_page, cc->page_pool); - bv->bv_page = NULL; - } -} - -static struct dm_crypt_io *crypt_io_alloc(struct dm_target *ti, - struct bio *bio, sector_t sector) -{ - struct crypt_config *cc = ti->private; - struct dm_crypt_io *io; - - io = mempool_alloc(cc->io_pool, GFP_NOIO); - io->target = ti; - io->base_bio = bio; - io->sector = sector; - io->error = 0; - io->base_io = NULL; - atomic_set(&io->pending, 0); - - return io; -} - -static void crypt_inc_pending(struct dm_crypt_io *io) -{ - atomic_inc(&io->pending); -} - -/* - * One of the bios was finished. Check for completion of - * the whole request and correctly clean up the buffer. - * If base_io is set, wait for the last fragment to complete. - */ -static void crypt_dec_pending(struct dm_crypt_io *io) -{ - struct crypt_config *cc = io->target->private; - struct bio *base_bio = io->base_bio; - struct dm_crypt_io *base_io = io->base_io; - int error = io->error; - - if (!atomic_dec_and_test(&io->pending)) - return; - - mempool_free(io, cc->io_pool); - - if (likely(!base_io)) - bio_endio(base_bio, error); - else { - if (error && !base_io->error) - base_io->error = error; - crypt_dec_pending(base_io); - } -} - -/* - * kcryptd/kcryptd_io: - * - * Needed because it would be very unwise to do decryption in an - * interrupt context. - * - * kcryptd performs the actual encryption or decryption. - * - * kcryptd_io performs the IO submission. - * - * 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) -{ - struct dm_crypt_io *io = clone->bi_private; - struct crypt_config *cc = io->target->private; - unsigned rw = bio_data_dir(clone); - - if (unlikely(!bio_flagged(clone, BIO_UPTODATE) && !error)) - error = -EIO; - - /* - * free the processed pages - */ - if (rw == WRITE) - crypt_free_buffer_pages(cc, clone); - - bio_put(clone); - - if (rw == READ && !error) { - kcryptd_queue_crypt(io); - return; - } - - if (unlikely(error)) - io->error = error; - - crypt_dec_pending(io); -} - -static void clone_init(struct dm_crypt_io *io, struct bio *clone) -{ - struct crypt_config *cc = io->target->private; - - clone->bi_private = io; - clone->bi_end_io = crypt_endio; - clone->bi_bdev = cc->dev->bdev; - clone->bi_rw = io->base_bio->bi_rw; - clone->bi_destructor = dm_crypt_bio_destructor; -} - -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; - - /* - * 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, bio_segments(base_bio), cc->bs); - if (!clone) - return 1; - - crypt_inc_pending(io); - - clone_init(io, clone); - clone->bi_idx = 0; - clone->bi_vcnt = bio_segments(base_bio); - clone->bi_size = base_bio->bi_size; - clone->bi_sector = cc->start + io->sector; - memcpy(clone->bi_io_vec, bio_iovec(base_bio), - sizeof(struct bio_vec) * clone->bi_vcnt); - - generic_make_request(clone); - return 0; -} - -static void kcryptd_io_write(struct dm_crypt_io *io) -{ - struct bio *clone = io->ctx.bio_out; - generic_make_request(clone); -} - -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) { - crypt_inc_pending(io); - if (kcryptd_io_read(io, GFP_NOIO)) - io->error = -ENOMEM; - crypt_dec_pending(io); - } else - kcryptd_io_write(io); -} - -static void kcryptd_queue_io(struct dm_crypt_io *io) -{ - struct crypt_config *cc = io->target->private; - - INIT_WORK(&io->work, kcryptd_io); - queue_work(cc->io_queue, &io->work); -} - -static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int async) -{ - struct bio *clone = io->ctx.bio_out; - struct crypt_config *cc = io->target->private; - - if (unlikely(io->error < 0)) { - crypt_free_buffer_pages(cc, clone); - bio_put(clone); - crypt_dec_pending(io); - return; - } - - /* crypt_convert should have filled the clone bio */ - BUG_ON(io->ctx.idx_out < clone->bi_vcnt); - - clone->bi_sector = cc->start + io->sector; - - if (async) - kcryptd_queue_io(io); - else - generic_make_request(clone); -} - -static void kcryptd_crypt_write_convert(struct dm_crypt_io *io) -{ - struct crypt_config *cc = io->target->private; - struct bio *clone; - struct dm_crypt_io *new_io; - int crypt_finished; - unsigned out_of_pages = 0; - unsigned remaining = io->base_bio->bi_size; - sector_t sector = io->sector; - int r; - - /* - * Prevent io from disappearing until this function completes. - */ - crypt_inc_pending(io); - crypt_convert_init(cc, &io->ctx, NULL, io->base_bio, sector); - - /* - * The allocated buffers can be smaller than the whole bio, - * so repeat the whole process until all the data can be handled. - */ - while (remaining) { - clone = crypt_alloc_buffer(io, remaining, &out_of_pages); - if (unlikely(!clone)) { - io->error = -ENOMEM; - break; - } - - io->ctx.bio_out = clone; - io->ctx.idx_out = 0; - - remaining -= clone->bi_size; - sector += bio_sectors(clone); - - crypt_inc_pending(io); - - r = crypt_convert(cc, &io->ctx); - if (r < 0) - io->error = -EIO; - - crypt_finished = atomic_dec_and_test(&io->ctx.pending); - - /* Encryption was already finished, submit io now */ - if (crypt_finished) { - kcryptd_crypt_write_io_submit(io, 0); - - /* - * If there was an error, do not try next fragments. - * For async, error is processed in async handler. - */ - if (unlikely(r < 0)) - break; - - io->sector = sector; - } - - /* - * Out of memory -> run queues - * But don't wait if split was due to the io size restriction - */ - if (unlikely(out_of_pages)) - congestion_wait(BLK_RW_ASYNC, HZ/100); - - /* - * With async crypto it is unsafe to share the crypto context - * between fragments, so switch to a new dm_crypt_io structure. - */ - if (unlikely(!crypt_finished && remaining)) { - new_io = crypt_io_alloc(io->target, io->base_bio, - sector); - crypt_inc_pending(new_io); - crypt_convert_init(cc, &new_io->ctx, NULL, - io->base_bio, sector); - new_io->ctx.idx_in = io->ctx.idx_in; - new_io->ctx.offset_in = io->ctx.offset_in; - - /* - * Fragments after the first use the base_io - * pending count. - */ - if (!io->base_io) - new_io->base_io = io; - else { - new_io->base_io = io->base_io; - crypt_inc_pending(io->base_io); - crypt_dec_pending(io); - } - - io = new_io; - } - } - - crypt_dec_pending(io); -} - -static void kcryptd_crypt_read_done(struct dm_crypt_io *io) -{ - crypt_dec_pending(io); -} - -static void kcryptd_crypt_read_convert(struct dm_crypt_io *io) -{ - struct crypt_config *cc = io->target->private; - int r = 0; - - crypt_inc_pending(io); - - crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio, - io->sector); - - r = crypt_convert(cc, &io->ctx); - if (r < 0) - io->error = -EIO; - - if (atomic_dec_and_test(&io->ctx.pending)) - kcryptd_crypt_read_done(io); - - crypt_dec_pending(io); -} - -static void kcryptd_async_done(struct crypto_async_request *async_req, - int error) -{ - struct dm_crypt_request *dmreq = async_req->data; - struct convert_context *ctx = dmreq->ctx; - struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx); - struct crypt_config *cc = io->target->private; - - if (error == -EINPROGRESS) { - complete(&ctx->restart); - 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); - - if (error < 0) - io->error = -EIO; - - mempool_free(req_of_dmreq(cc, dmreq), cc->req_pool); - - if (!atomic_dec_and_test(&ctx->pending)) - return; - - if (bio_data_dir(io->base_bio) == READ) - kcryptd_crypt_read_done(io); - else - kcryptd_crypt_write_io_submit(io, 1); -} - -static void kcryptd_crypt(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_crypt_read_convert(io); - else - kcryptd_crypt_write_convert(io); -} - -static void kcryptd_queue_crypt(struct dm_crypt_io *io) -{ - struct crypt_config *cc = io->target->private; - - INIT_WORK(&io->work, kcryptd_crypt); - queue_work(cc->crypt_queue, &io->work); -} - -/* - * Decode key from its hex representation - */ -static int crypt_decode_key(u8 *key, char *hex, unsigned int size) -{ - char buffer[3]; - char *endp; - unsigned int i; - - buffer[2] = '\0'; - - for (i = 0; i < size; i++) { - buffer[0] = *hex++; - buffer[1] = *hex++; - - key[i] = (u8)simple_strtoul(buffer, &endp, 16); - - if (endp != &buffer[2]) - return -EINVAL; - } - - if (*hex != '\0') - return -EINVAL; - - return 0; -} - -/* - * Encode key into its hex representation - */ -static void crypt_encode_key(char *hex, u8 *key, unsigned int size) -{ - unsigned int i; - - for (i = 0; i < size; i++) { - sprintf(hex, "%02x", *key); - hex += 2; - key++; - } -} - -static void crypt_free_tfms(struct crypt_config *cc, int cpu) -{ - struct crypt_cpu *cpu_cc = per_cpu_ptr(cc->cpu, cpu); - unsigned i; - - 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) -{ - int r = -EINVAL; - int key_string_len = strlen(key); - - /* The key size may not be changed. */ - if (cc->key_size != (key_string_len >> 1)) - goto out; - - /* Hyphen (which gives a key_size of zero) means there is no key. */ - if (!cc->key_size && strcmp(key, "-")) - goto out; - - if (cc->key_size && crypt_decode_key(cc->key, key, cc->key_size) < 0) - goto out; - - set_bit(DM_CRYPT_KEY_VALID, &cc->flags); - - r = crypt_setkey_allcpus(cc); - -out: - /* Hex key string not needed after here, so wipe it. */ - memset(key, '0', key_string_len); - - return r; -} - -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 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; - - if (!cc) - return; - - if (cc->io_queue) - destroy_workqueue(cc->io_queue); - 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); - - 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->dev) - dm_put_device(ti, cc->dev); - - if (cc->cpu) - free_percpu(cc->cpu); - - kzfree(cc->cipher); - kzfree(cc->cipher_string); - - /* 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, *keycount; - char *cipher_api = NULL; - int cpu, ret = -EINVAL; - char dummy; - - /* Convert to crypto api definition? */ - if (strchr(cipher_in, '(')) { - ti->error = "Bad cipher specification"; - return -EINVAL; - } - - cc->cipher_string = kstrdup(cipher_in, GFP_KERNEL); - if (!cc->cipher_string) - goto bad_mem; - - /* - * Legacy dm-crypt cipher specification - * cipher[:keycount]-mode-iv:ivopts - */ - tmp = cipher_in; - keycount = strsep(&tmp, "-"); - cipher = strsep(&keycount, ":"); - - if (!keycount) - cc->tfms_count = 1; - else if (sscanf(keycount, "%u%c", &cc->tfms_count, &dummy) != 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; - - chainmode = strsep(&tmp, "-"); - ivopts = strsep(&tmp, "-"); - ivmode = strsep(&ivopts, ":"); - - if (tmp) - DMWARN("Ignoring unexpected additional cipher options"); - - 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)) { - chainmode = "cbc"; - ivmode = "plain"; - } - - if (strcmp(chainmode, "ecb") && !ivmode) { - ti->error = "IV mechanism required"; - return -EINVAL; - } - - 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; - } - - /* Allocate cipher */ - 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 */ - ret = crypt_set_key(cc, key); - if (ret < 0) { - ti->error = "Error decoding and setting key"; - goto bad; - } - - /* Initialize IV */ - 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, - (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) - cc->iv_gen_ops = &crypt_iv_plain_ops; - else if (strcmp(ivmode, "plain64") == 0) - cc->iv_gen_ops = &crypt_iv_plain64_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 if (strcmp(ivmode, "null") == 0) - cc->iv_gen_ops = &crypt_iv_null_ops; - 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; - } - - /* 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; - } - } - - /* 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, opt_params; - unsigned long long tmpll; - int ret; - struct dm_arg_set as; - const char *opt_string; - char dummy; - - static struct dm_arg _args[] = { - {0, 1, "Invalid number of feature args"}, - }; - - 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; - } - cc->key_size = key_size; - - 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; - } - - cc->dmreq_start = sizeof(struct ablkcipher_request); - 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(any_tfm(cc)) & - ~(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; - } - - cc->page_pool = mempool_create_page_pool(MIN_POOL_PAGES, 0); - if (!cc->page_pool) { - ti->error = "Cannot allocate page mempool"; - goto bad; - } - - cc->bs = bioset_create(MIN_IOS, 0); - if (!cc->bs) { - ti->error = "Cannot allocate crypt bioset"; - goto bad; - } - - ret = -EINVAL; - if (sscanf(argv[2], "%llu%c", &tmpll, &dummy) != 1) { - ti->error = "Invalid iv_offset sector"; - goto bad; - } - cc->iv_offset = tmpll; - - if (dm_get_device(ti, argv[3], dm_table_get_mode(ti->table), &cc->dev)) { - ti->error = "Device lookup failed"; - goto bad; - } - - if (sscanf(argv[4], "%llu%c", &tmpll, &dummy) != 1) { - ti->error = "Invalid device sector"; - goto bad; - } - cc->start = tmpll; - - argv += 5; - argc -= 5; - - /* Optional parameters */ - if (argc) { - as.argc = argc; - as.argv = argv; - - ret = dm_read_arg_group(_args, &as, &opt_params, &ti->error); - if (ret) - goto bad; - - opt_string = dm_shift_arg(&as); - - if (opt_params == 1 && opt_string && - !strcasecmp(opt_string, "allow_discards")) - ti->num_discard_requests = 1; - else if (opt_params) { - ret = -EINVAL; - ti->error = "Invalid feature arguments"; - goto bad; - } - } - - ret = -ENOMEM; - 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 = 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; - } - - ti->num_flush_requests = 1; - ti->discard_zeroes_data_unsupported = 1; - - return 0; - -bad: - crypt_dtr(ti); - return ret; -} - -static int crypt_map(struct dm_target *ti, struct bio *bio, - union map_info *map_context) -{ - struct dm_crypt_io *io; - struct crypt_config *cc; - - /* - * If bio is REQ_FLUSH or REQ_DISCARD, just bypass crypt queues. - * - for REQ_FLUSH device-mapper core ensures that no IO is in-flight - * - for REQ_DISCARD caller must use flush if IO ordering matters - */ - if (unlikely(bio->bi_rw & (REQ_FLUSH | REQ_DISCARD))) { - cc = ti->private; - bio->bi_bdev = cc->dev->bdev; - if (bio_sectors(bio)) - bio->bi_sector = cc->start + dm_target_offset(ti, bio->bi_sector); - return DM_MAPIO_REMAPPED; - } - - io = crypt_io_alloc(ti, bio, dm_target_offset(ti, bio->bi_sector)); - - 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; -} - -static int crypt_status(struct dm_target *ti, status_type_t type, - char *result, unsigned int maxlen) -{ - struct crypt_config *cc = ti->private; - unsigned int sz = 0; - - switch (type) { - case STATUSTYPE_INFO: - result[0] = '\0'; - break; - - case STATUSTYPE_TABLE: - DMEMIT("%s ", cc->cipher_string); - - if (cc->key_size > 0) { - if ((maxlen - sz) < ((cc->key_size << 1) + 1)) - return -ENOMEM; - - crypt_encode_key(result + sz, cc->key, cc->key_size); - sz += cc->key_size << 1; - } else { - if (sz >= maxlen) - return -ENOMEM; - result[sz++] = '-'; - } - - DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset, - cc->dev->name, (unsigned long long)cc->start); - - if (ti->num_discard_requests) - DMEMIT(" 1 allow_discards"); - - break; - } - return 0; -} - -static void crypt_postsuspend(struct dm_target *ti) -{ - struct crypt_config *cc = ti->private; - - set_bit(DM_CRYPT_SUSPENDED, &cc->flags); -} - -static int crypt_preresume(struct dm_target *ti) -{ - struct crypt_config *cc = ti->private; - - if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) { - DMERR("aborting resume - crypt key is not set."); - return -EAGAIN; - } - - return 0; -} - -static void crypt_resume(struct dm_target *ti) -{ - struct crypt_config *cc = ti->private; - - clear_bit(DM_CRYPT_SUSPENDED, &cc->flags); -} - -/* Message interface - * key set <key> - * key wipe - */ -static int crypt_message(struct dm_target *ti, unsigned argc, char **argv) -{ - struct crypt_config *cc = ti->private; - int ret = -EINVAL; - - if (argc < 2) - goto error; - - if (!strcasecmp(argv[0], "key")) { - if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) { - DMWARN("not suspended during key manipulation."); - return -EINVAL; - } - if (argc == 3 && !strcasecmp(argv[1], "set")) { - ret = crypt_set_key(cc, argv[2]); - if (ret) - return ret; - if (cc->iv_gen_ops && cc->iv_gen_ops->init) - ret = cc->iv_gen_ops->init(cc); - return ret; - } - if (argc == 2 && !strcasecmp(argv[1], "wipe")) { - if (cc->iv_gen_ops && cc->iv_gen_ops->wipe) { - ret = cc->iv_gen_ops->wipe(cc); - if (ret) - return ret; - } - return crypt_wipe_key(cc); - } - } - -error: - DMWARN("unrecognised message received."); - return -EINVAL; -} - -static int crypt_merge(struct dm_target *ti, struct bvec_merge_data *bvm, - struct bio_vec *biovec, int max_size) -{ - struct crypt_config *cc = ti->private; - struct request_queue *q = bdev_get_queue(cc->dev->bdev); - - if (!q->merge_bvec_fn) - return max_size; - - bvm->bi_bdev = cc->dev->bdev; - bvm->bi_sector = cc->start + dm_target_offset(ti, bvm->bi_sector); - - return min(max_size, q->merge_bvec_fn(q, bvm, biovec)); -} - -static int crypt_iterate_devices(struct dm_target *ti, - iterate_devices_callout_fn fn, void *data) -{ - struct crypt_config *cc = ti->private; - - return fn(ti, cc->dev, cc->start, ti->len, data); -} - -static struct target_type crypt_target = { - .name = "crypt", - .version = {1, 11, 0}, - .module = THIS_MODULE, - .ctr = crypt_ctr, - .dtr = crypt_dtr, - .map = crypt_map, - .status = crypt_status, - .postsuspend = crypt_postsuspend, - .preresume = crypt_preresume, - .resume = crypt_resume, - .message = crypt_message, - .merge = crypt_merge, - .iterate_devices = crypt_iterate_devices, -}; - -static int __init dm_crypt_init(void) -{ - int r; - - _crypt_io_pool = KMEM_CACHE(dm_crypt_io, 0); - if (!_crypt_io_pool) - return -ENOMEM; - - r = dm_register_target(&crypt_target); - if (r < 0) { - DMERR("register failed %d", r); - kmem_cache_destroy(_crypt_io_pool); - } - - return r; -} - -static void __exit dm_crypt_exit(void) -{ - dm_unregister_target(&crypt_target); - kmem_cache_destroy(_crypt_io_pool); -} - -module_init(dm_crypt_init); -module_exit(dm_crypt_exit); - -MODULE_AUTHOR("Christophe Saout <christophe@saout.de>"); -MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption"); -MODULE_LICENSE("GPL"); |