diff options
| -rw-r--r-- | crypto/cts.c | 495 |
1 files changed, 285 insertions, 210 deletions
diff --git a/crypto/cts.c b/crypto/cts.c index e467ec0acf9f..51976187b2bf 100644 --- a/crypto/cts.c +++ b/crypto/cts.c @@ -40,7 +40,7 @@ * rfc3962 includes errata information in its Appendix A. */ -#include <crypto/algapi.h> +#include <crypto/internal/skcipher.h> #include <linux/err.h> #include <linux/init.h> #include <linux/kernel.h> @@ -51,289 +51,364 @@ #include <linux/slab.h> struct crypto_cts_ctx { - struct crypto_blkcipher *child; + struct crypto_skcipher *child; }; -static int crypto_cts_setkey(struct crypto_tfm *parent, const u8 *key, - unsigned int keylen) +struct crypto_cts_reqctx { + struct scatterlist sg[2]; + unsigned offset; + struct skcipher_request subreq; +}; + +static inline u8 *crypto_cts_reqctx_space(struct skcipher_request *req) { - struct crypto_cts_ctx *ctx = crypto_tfm_ctx(parent); - struct crypto_blkcipher *child = ctx->child; - int err; + struct crypto_cts_reqctx *rctx = skcipher_request_ctx(req); + struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); + struct crypto_cts_ctx *ctx = crypto_skcipher_ctx(tfm); + struct crypto_skcipher *child = ctx->child; - crypto_blkcipher_clear_flags(child, CRYPTO_TFM_REQ_MASK); - crypto_blkcipher_set_flags(child, crypto_tfm_get_flags(parent) & - CRYPTO_TFM_REQ_MASK); - err = crypto_blkcipher_setkey(child, key, keylen); - crypto_tfm_set_flags(parent, crypto_blkcipher_get_flags(child) & - CRYPTO_TFM_RES_MASK); - return err; + return PTR_ALIGN((u8 *)(rctx + 1) + crypto_skcipher_reqsize(child), + crypto_skcipher_alignmask(tfm) + 1); } -static int cts_cbc_encrypt(struct crypto_cts_ctx *ctx, - struct blkcipher_desc *desc, - struct scatterlist *dst, - struct scatterlist *src, - unsigned int offset, - unsigned int nbytes) +static int crypto_cts_setkey(struct crypto_skcipher *parent, const u8 *key, + unsigned int keylen) { - int bsize = crypto_blkcipher_blocksize(desc->tfm); - u8 tmp[bsize], tmp2[bsize]; - struct blkcipher_desc lcldesc; - struct scatterlist sgsrc[1], sgdst[1]; - int lastn = nbytes - bsize; - u8 iv[bsize]; - u8 s[bsize * 2], d[bsize * 2]; + struct crypto_cts_ctx *ctx = crypto_skcipher_ctx(parent); + struct crypto_skcipher *child = ctx->child; int err; - if (lastn < 0) - return -EINVAL; + crypto_skcipher_clear_flags(child, CRYPTO_TFM_REQ_MASK); + crypto_skcipher_set_flags(child, crypto_skcipher_get_flags(parent) & + CRYPTO_TFM_REQ_MASK); + err = crypto_skcipher_setkey(child, key, keylen); + crypto_skcipher_set_flags(parent, crypto_skcipher_get_flags(child) & + CRYPTO_TFM_RES_MASK); + return err; +} - sg_init_table(sgsrc, 1); - sg_init_table(sgdst, 1); +static void cts_cbc_crypt_done(struct crypto_async_request *areq, int err) +{ + struct skcipher_request *req = areq->data; - memset(s, 0, sizeof(s)); - scatterwalk_map_and_copy(s, src, offset, nbytes, 0); + if (err == -EINPROGRESS) + return; - memcpy(iv, desc->info, bsize); + skcipher_request_complete(req, err); +} - lcldesc.tfm = ctx->child; - lcldesc.info = iv; - lcldesc.flags = desc->flags; +static int cts_cbc_encrypt(struct skcipher_request *req) +{ + struct crypto_cts_reqctx *rctx = skcipher_request_ctx(req); + struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); + struct skcipher_request *subreq = &rctx->subreq; + int bsize = crypto_skcipher_blocksize(tfm); + u8 d[bsize * 2] __attribute__ ((aligned(__alignof__(u32)))); + struct scatterlist *sg; + unsigned int offset; + int lastn; + + offset = rctx->offset; + lastn = req->cryptlen - offset; + + sg = scatterwalk_ffwd(rctx->sg, req->dst, offset - bsize); + scatterwalk_map_and_copy(d + bsize, sg, 0, bsize, 0); + + memset(d, 0, bsize); + scatterwalk_map_and_copy(d, req->src, offset, lastn, 0); + + scatterwalk_map_and_copy(d, sg, 0, bsize + lastn, 1); + memzero_explicit(d, sizeof(d)); + + skcipher_request_set_callback(subreq, req->base.flags & + CRYPTO_TFM_REQ_MAY_BACKLOG, + cts_cbc_crypt_done, req); + skcipher_request_set_crypt(subreq, sg, sg, bsize, req->iv); + return crypto_skcipher_encrypt(subreq); +} - sg_set_buf(&sgsrc[0], s, bsize); - sg_set_buf(&sgdst[0], tmp, bsize); - err = crypto_blkcipher_encrypt_iv(&lcldesc, sgdst, sgsrc, bsize); +static void crypto_cts_encrypt_done(struct crypto_async_request *areq, int err) +{ + struct skcipher_request *req = areq->data; - memcpy(d + bsize, tmp, lastn); + if (err) + goto out; - lcldesc.info = tmp; + err = cts_cbc_encrypt(req); + if (err == -EINPROGRESS || + (err == -EBUSY && req->base.flags & CRYPTO_TFM_REQ_MAY_BACKLOG)) + return; - sg_set_buf(&sgsrc[0], s + bsize, bsize); - sg_set_buf(&sgdst[0], tmp2, bsize); - err = crypto_blkcipher_encrypt_iv(&lcldesc, sgdst, sgsrc, bsize); +out: + skcipher_request_complete(req, err); +} - memcpy(d, tmp2, bsize); +static int crypto_cts_encrypt(struct skcipher_request *req) +{ + struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); + struct crypto_cts_reqctx *rctx = skcipher_request_ctx(req); + struct crypto_cts_ctx *ctx = crypto_skcipher_ctx(tfm); + struct skcipher_request *subreq = &rctx->subreq; + int bsize = crypto_skcipher_blocksize(tfm); + unsigned int nbytes = req->cryptlen; + int cbc_blocks = (nbytes + bsize - 1) / bsize - 1; + unsigned int offset; + + skcipher_request_set_tfm(subreq, ctx->child); + + if (cbc_blocks <= 0) { + skcipher_request_set_callback(subreq, req->base.flags, + req->base.complete, + req->base.data); + skcipher_request_set_crypt(subreq, req->src, req->dst, nbytes, + req->iv); + return crypto_skcipher_encrypt(subreq); + } - scatterwalk_map_and_copy(d, dst, offset, nbytes, 1); + offset = cbc_blocks * bsize; + rctx->offset = offset; - memcpy(desc->info, tmp2, bsize); + skcipher_request_set_callback(subreq, req->base.flags, + crypto_cts_encrypt_done, req); + skcipher_request_set_crypt(subreq, req->src, req->dst, + offset, req->iv); - return err; + return crypto_skcipher_encrypt(subreq) ?: + cts_cbc_encrypt(req); } -static int crypto_cts_encrypt(struct blkcipher_desc *desc, - struct scatterlist *dst, struct scatterlist *src, - unsigned int nbytes) +static int cts_cbc_decrypt(struct skcipher_request *req) { - struct crypto_cts_ctx *ctx = crypto_blkcipher_ctx(desc->tfm); - int bsize = crypto_blkcipher_blocksize(desc->tfm); - int tot_blocks = (nbytes + bsize - 1) / bsize; - int cbc_blocks = tot_blocks > 2 ? tot_blocks - 2 : 0; - struct blkcipher_desc lcldesc; - int err; + struct crypto_cts_reqctx *rctx = skcipher_request_ctx(req); + struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); + struct skcipher_request *subreq = &rctx->subreq; + int bsize = crypto_skcipher_blocksize(tfm); + u8 d[bsize * 2] __attribute__ ((aligned(__alignof__(u32)))); + struct scatterlist *sg; + unsigned int offset; + u8 *space; + int lastn; + + offset = rctx->offset; + lastn = req->cryptlen - offset; + + sg = scatterwalk_ffwd(rctx->sg, req->dst, offset - bsize); + + /* 1. Decrypt Cn-1 (s) to create Dn */ + scatterwalk_map_and_copy(d + bsize, sg, 0, bsize, 0); + space = crypto_cts_reqctx_space(req); + crypto_xor(d + bsize, space, bsize); + /* 2. Pad Cn with zeros at the end to create C of length BB */ + memset(d, 0, bsize); + scatterwalk_map_and_copy(d, req->src, offset, lastn, 0); + /* 3. Exclusive-or Dn with C to create Xn */ + /* 4. Select the first Ln bytes of Xn to create Pn */ + crypto_xor(d + bsize, d, lastn); + + /* 5. Append the tail (BB - Ln) bytes of Xn to Cn to create En */ + memcpy(d + lastn, d + bsize + lastn, bsize - lastn); + /* 6. Decrypt En to create Pn-1 */ - lcldesc.tfm = ctx->child; - lcldesc.info = desc->info; - lcldesc.flags = desc->flags; - - if (tot_blocks == 1) { - err = crypto_blkcipher_encrypt_iv(&lcldesc, dst, src, bsize); - } else if (nbytes <= bsize * 2) { - err = cts_cbc_encrypt(ctx, desc, dst, src, 0, nbytes); - } else { - /* do normal function for tot_blocks - 2 */ - err = crypto_blkcipher_encrypt_iv(&lcldesc, dst, src, - cbc_blocks * bsize); - if (err == 0) { - /* do cts for final two blocks */ - err = cts_cbc_encrypt(ctx, desc, dst, src, - cbc_blocks * bsize, - nbytes - (cbc_blocks * bsize)); - } - } + scatterwalk_map_and_copy(d, sg, 0, bsize + lastn, 1); + memzero_explicit(d, sizeof(d)); - return err; + skcipher_request_set_callback(subreq, req->base.flags & + CRYPTO_TFM_REQ_MAY_BACKLOG, + cts_cbc_crypt_done, req); + + skcipher_request_set_crypt(subreq, sg, sg, bsize, space); + return crypto_skcipher_decrypt(subreq); } -static int cts_cbc_decrypt(struct crypto_cts_ctx *ctx, - struct blkcipher_desc *desc, - struct scatterlist *dst, - struct scatterlist *src, - unsigned int offset, - unsigned int nbytes) +static void crypto_cts_decrypt_done(struct crypto_async_request *areq, int err) { - int bsize = crypto_blkcipher_blocksize(desc->tfm); - u8 tmp[bsize]; - struct blkcipher_desc lcldesc; - struct scatterlist sgsrc[1], sgdst[1]; - int lastn = nbytes - bsize; - u8 iv[bsize]; - u8 s[bsize * 2], d[bsize * 2]; - int err; - - if (lastn < 0) - return -EINVAL; + struct skcipher_request *req = areq->data; - sg_init_table(sgsrc, 1); - sg_init_table(sgdst, 1); + if (err) + goto out; - scatterwalk_map_and_copy(s, src, offset, nbytes, 0); + err = cts_cbc_decrypt(req); + if (err == -EINPROGRESS || + (err == -EBUSY && req->base.flags & CRYPTO_TFM_REQ_MAY_BACKLOG)) + return; - lcldesc.tfm = ctx->child; - lcldesc.info = iv; - lcldesc.flags = desc->flags; +out: + skcipher_request_complete(req, err); +} - /* 1. Decrypt Cn-1 (s) to create Dn (tmp)*/ - memset(iv, 0, sizeof(iv)); - sg_set_buf(&sgsrc[0], s, bsize); - sg_set_buf(&sgdst[0], tmp, bsize); - err = crypto_blkcipher_decrypt_iv(&lcldesc, sgdst, sgsrc, bsize); - if (err) - return err; - /* 2. Pad Cn with zeros at the end to create C of length BB */ - memset(iv, 0, sizeof(iv)); - memcpy(iv, s + bsize, lastn); - /* 3. Exclusive-or Dn (tmp) with C (iv) to create Xn (tmp) */ - crypto_xor(tmp, iv, bsize); - /* 4. Select the first Ln bytes of Xn (tmp) to create Pn */ - memcpy(d + bsize, tmp, lastn); - - /* 5. Append the tail (BB - Ln) bytes of Xn (tmp) to Cn to create En */ - memcpy(s + bsize + lastn, tmp + lastn, bsize - lastn); - /* 6. Decrypt En to create Pn-1 */ - memzero_explicit(iv, sizeof(iv)); +static int crypto_cts_decrypt(struct skcipher_request *req) +{ + struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); + struct crypto_cts_reqctx *rctx = skcipher_request_ctx(req); + struct crypto_cts_ctx *ctx = crypto_skcipher_ctx(tfm); + struct skcipher_request *subreq = &rctx->subreq; + int bsize = crypto_skcipher_blocksize(tfm); + unsigned int nbytes = req->cryptlen; + int cbc_blocks = (nbytes + bsize - 1) / bsize - 1; + unsigned int offset; + u8 *space; + + skcipher_request_set_tfm(subreq, ctx->child); + + if (cbc_blocks <= 0) { + skcipher_request_set_callback(subreq, req->base.flags, + req->base.complete, + req->base.data); + skcipher_request_set_crypt(subreq, req->src, req->dst, nbytes, + req->iv); + return crypto_skcipher_decrypt(subreq); + } - sg_set_buf(&sgsrc[0], s + bsize, bsize); - sg_set_buf(&sgdst[0], d, bsize); - err = crypto_blkcipher_decrypt_iv(&lcldesc, sgdst, sgsrc, bsize); + skcipher_request_set_callback(subreq, req->base.flags, + crypto_cts_decrypt_done, req); - /* XOR with previous block */ - crypto_xor(d, desc->info, bsize); + space = crypto_cts_reqctx_space(req); - scatterwalk_map_and_copy(d, dst, offset, nbytes, 1); + offset = cbc_blocks * bsize; + rctx->offset = offset; - memcpy(desc->info, s, bsize); - return err; -} + if (cbc_blocks <= 1) + memcpy(space, req->iv, bsize); + else + scatterwalk_map_and_copy(space, req->src, offset - 2 * bsize, + bsize, 0); -static int crypto_cts_decrypt(struct blkcipher_desc *desc, - struct scatterlist *dst, struct scatterlist *src, - unsigned int nbytes) -{ - struct crypto_cts_ctx *ctx = crypto_blkcipher_ctx(desc->tfm); - int bsize = crypto_blkcipher_blocksize(desc->tfm); - int tot_blocks = (nbytes + bsize - 1) / bsize; - int cbc_blocks = tot_blocks > 2 ? tot_blocks - 2 : 0; - struct blkcipher_desc lcldesc; - int err; + skcipher_request_set_crypt(subreq, req->src, req->dst, + offset, req->iv); - lcldesc.tfm = ctx->child; - lcldesc.info = desc->info; - lcldesc.flags = desc->flags; - - if (tot_blocks == 1) { - err = crypto_blkcipher_decrypt_iv(&lcldesc, dst, src, bsize); - } else if (nbytes <= bsize * 2) { - err = cts_cbc_decrypt(ctx, desc, dst, src, 0, nbytes); - } else { - /* do normal function for tot_blocks - 2 */ - err = crypto_blkcipher_decrypt_iv(&lcldesc, dst, src, - cbc_blocks * bsize); - if (err == 0) { - /* do cts for final two blocks */ - err = cts_cbc_decrypt(ctx, desc, dst, src, - cbc_blocks * bsize, - nbytes - (cbc_blocks * bsize)); - } - } - return err; + return crypto_skcipher_decrypt(subreq) ?: + cts_cbc_decrypt(req); } -static int crypto_cts_init_tfm(struct crypto_tfm *tfm) +static int crypto_cts_init_tfm(struct crypto_skcipher *tfm) { - struct crypto_instance *inst = (void *)tfm->__crt_alg; - struct crypto_spawn *spawn = crypto_instance_ctx(inst); - struct crypto_cts_ctx *ctx = crypto_tfm_ctx(tfm); - struct crypto_blkcipher *cipher; - - cipher = crypto_spawn_blkcipher(spawn); + struct skcipher_instance *inst = skcipher_alg_instance(tfm); + struct crypto_skcipher_spawn *spawn = skcipher_instance_ctx(inst); + struct crypto_cts_ctx *ctx = crypto_skcipher_ctx(tfm); + struct crypto_skcipher *cipher; + unsigned reqsize; + unsigned bsize; + unsigned align; + + cipher = crypto_spawn_skcipher2(spawn); if (IS_ERR(cipher)) return PTR_ERR(cipher); ctx->child = cipher; + + align = crypto_skcipher_alignmask(tfm); + bsize = crypto_skcipher_blocksize(cipher); + reqsize = ALIGN(sizeof(struct crypto_cts_reqctx) + + crypto_skcipher_reqsize(cipher), + crypto_tfm_ctx_alignment()) + + (align & ~(crypto_tfm_ctx_alignment() - 1)) + bsize; + + crypto_skcipher_set_reqsize(tfm, reqsize); + return 0; } -static void crypto_cts_exit_tfm(struct crypto_tfm *tfm) +static void crypto_cts_exit_tfm(struct crypto_skcipher *tfm) { - struct crypto_cts_ctx *ctx = crypto_tfm_ctx(tfm); - crypto_free_blkcipher(ctx->child); + struct crypto_cts_ctx *ctx = crypto_skcipher_ctx(tfm); + + crypto_free_skcipher(ctx->child); } -static struct crypto_instance *crypto_cts_alloc(struct rtattr **tb) +static void crypto_cts_free(struct skcipher_instance *inst) { - struct crypto_instance *inst; - struct crypto_alg *alg; + crypto_drop_skcipher(skcipher_instance_ctx(inst)); + kfree(inst); +} + +static int crypto_cts_create(struct crypto_template *tmpl, struct rtattr **tb) +{ + struct crypto_skcipher_spawn *spawn; + struct skcipher_instance *inst; + struct crypto_attr_type *algt; + struct skcipher_alg *alg; + const char *cipher_name; int err; - err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_BLKCIPHER); + algt = crypto_get_attr_type(tb); + if (IS_ERR(algt)) + return PTR_ERR(algt); + + if ((algt->type ^ CRYPTO_ALG_TYPE_SKCIPHER) & algt->mask) + return -EINVAL; + + cipher_name = crypto_attr_alg_name(tb[1]); + if (IS_ERR(cipher_name)) + return PTR_ERR(cipher_name); + + inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL); + if (!inst) + return -ENOMEM; + + spawn = skcipher_instance_ctx(inst); + + crypto_set_skcipher_spawn(spawn, skcipher_crypto_instance(inst)); + err = crypto_grab_skcipher2(spawn, cipher_name, 0, + crypto_requires_sync(algt->type, + algt->mask)); if (err) - return ERR_PTR(err); + goto err_free_inst; - alg = crypto_attr_alg(tb[1], CRYPTO_ALG_TYPE_BLKCIPHER, - CRYPTO_ALG_TYPE_MASK); - if (IS_ERR(alg)) - return ERR_CAST(alg); + alg = crypto_spawn_skcipher_alg(spawn); - inst = ERR_PTR(-EINVAL); - if (!is_power_of_2(alg->cra_blocksize)) - goto out_put_alg; + err = -EINVAL; + if (crypto_skcipher_alg_ivsize(alg) != alg->base.cra_blocksize) + goto err_drop_spawn; - if (strncmp(alg->cra_name, "cbc(", 4)) - goto out_put_alg; + if (strncmp(alg->base.cra_name, "cbc(", 4)) + goto err_drop_spawn; - inst = crypto_alloc_instance("cts", alg); - if (IS_ERR(inst)) - goto out_put_alg; + err = crypto_inst_setname(skcipher_crypto_instance(inst), "cts", + &alg->base); + if (err) + goto err_drop_spawn; - inst->alg.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER; - inst->alg.cra_priority = alg->cra_priority; - inst->alg.cra_blocksize = alg->cra_blocksize; - inst->alg.cra_alignmask = alg->cra_alignmask; - inst->alg.cra_type = &crypto_blkcipher_type; + inst->alg.base.cra_flags = alg->base.cra_flags & CRYPTO_ALG_ASYNC; + inst->alg.base.cra_priority = alg->base.cra_priority; + inst->alg.base.cra_blocksize = alg->base.cra_blocksize; + inst->alg.base.cra_alignmask = alg->base.cra_alignmask; /* We access the data as u32s when xoring. */ - inst->alg.cra_alignmask |= __alignof__(u32) - 1; + inst->alg.base.cra_alignmask |= __alignof__(u32) - 1; - inst->alg.cra_blkcipher.ivsize = alg->cra_blocksize; - inst->alg.cra_blkcipher.min_keysize = alg->cra_blkcipher.min_keysize; - inst->alg.cra_blkcipher.max_keysize = alg->cra_blkcipher.max_keysize; + inst->alg.ivsize = alg->base.cra_blocksize; + inst->alg.chunksize = crypto_skcipher_alg_chunksize(alg); + inst->alg.min_keysize = crypto_skcipher_alg_min_keysize(alg); + inst->alg.max_keysize = crypto_skcipher_alg_max_keysize(alg); - inst->alg.cra_ctxsize = sizeof(struct crypto_cts_ctx); + inst->alg.base.cra_ctxsize = sizeof(struct crypto_cts_ctx); - inst->alg.cra_init = crypto_cts_init_tfm; - inst->alg.cra_exit = crypto_cts_exit_tfm; + inst->alg.init = crypto_cts_init_tfm; + inst->alg.exit = crypto_cts_exit_tfm; - inst->alg.cra_blkcipher.setkey = crypto_cts_setkey; - inst->alg.cra_blkcipher.encrypt = crypto_cts_encrypt; - inst->alg.cra_blkcipher.decrypt = crypto_cts_decrypt; + inst->alg.setkey = crypto_cts_setkey; + inst->alg.encrypt = crypto_cts_encrypt; + inst->alg.decrypt = crypto_cts_decrypt; -out_put_alg: - crypto_mod_put(alg); - return inst; -} + inst->free = crypto_cts_free; -static void crypto_cts_free(struct crypto_instance *inst) -{ - crypto_drop_spawn(crypto_instance_ctx(inst)); + err = skcipher_register_instance(tmpl, inst); + if (err) + goto err_drop_spawn; + +out: + return err; + +err_drop_spawn: + crypto_drop_skcipher(spawn); +err_free_inst: kfree(inst); + goto out; } static struct crypto_template crypto_cts_tmpl = { .name = "cts", - .alloc = crypto_cts_alloc, - .free = crypto_cts_free, + .create = crypto_cts_create, .module = THIS_MODULE, }; |