diff options
Diffstat (limited to 'crypto')
| -rw-r--r-- | crypto/adiantum.c | 65 |
1 files changed, 47 insertions, 18 deletions
diff --git a/crypto/adiantum.c b/crypto/adiantum.c index 51703746d91e..aa0f8b3b499a 100644 --- a/crypto/adiantum.c +++ b/crypto/adiantum.c @@ -245,10 +245,9 @@ static void adiantum_hash_header(struct skcipher_request *req) /* Hash the left-hand part (the "bulk") of the message using NHPoly1305 */ static int adiantum_hash_message(struct skcipher_request *req, - struct scatterlist *sgl, le128 *digest) + struct scatterlist *sgl, unsigned int nents, + le128 *digest) { - struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); - const struct adiantum_tfm_ctx *tctx = crypto_skcipher_ctx(tfm); struct adiantum_request_ctx *rctx = skcipher_request_ctx(req); const unsigned int bulk_len = req->cryptlen - BLOCKCIPHER_BLOCK_SIZE; struct shash_desc *hash_desc = &rctx->u.hash_desc; @@ -256,14 +255,11 @@ static int adiantum_hash_message(struct skcipher_request *req, unsigned int i, n; int err; - hash_desc->tfm = tctx->hash; - err = crypto_shash_init(hash_desc); if (err) return err; - sg_miter_start(&miter, sgl, sg_nents(sgl), - SG_MITER_FROM_SG | SG_MITER_ATOMIC); + sg_miter_start(&miter, sgl, nents, SG_MITER_FROM_SG | SG_MITER_ATOMIC); for (i = 0; i < bulk_len; i += n) { sg_miter_next(&miter); n = min_t(unsigned int, miter.length, bulk_len - i); @@ -285,6 +281,8 @@ static int adiantum_finish(struct skcipher_request *req) const struct adiantum_tfm_ctx *tctx = crypto_skcipher_ctx(tfm); struct adiantum_request_ctx *rctx = skcipher_request_ctx(req); const unsigned int bulk_len = req->cryptlen - BLOCKCIPHER_BLOCK_SIZE; + struct scatterlist *dst = req->dst; + const unsigned int dst_nents = sg_nents(dst); le128 digest; int err; @@ -298,13 +296,30 @@ static int adiantum_finish(struct skcipher_request *req) * enc: C_R = C_M - H_{K_H}(T, C_L) * dec: P_R = P_M - H_{K_H}(T, P_L) */ - err = adiantum_hash_message(req, req->dst, &digest); - if (err) - return err; - le128_add(&digest, &digest, &rctx->header_hash); - le128_sub(&rctx->rbuf.bignum, &rctx->rbuf.bignum, &digest); - scatterwalk_map_and_copy(&rctx->rbuf.bignum, req->dst, - bulk_len, BLOCKCIPHER_BLOCK_SIZE, 1); + rctx->u.hash_desc.tfm = tctx->hash; + le128_sub(&rctx->rbuf.bignum, &rctx->rbuf.bignum, &rctx->header_hash); + if (dst_nents == 1 && dst->offset + req->cryptlen <= PAGE_SIZE) { + /* Fast path for single-page destination */ + void *virt = kmap_local_page(sg_page(dst)) + dst->offset; + + err = crypto_shash_digest(&rctx->u.hash_desc, virt, bulk_len, + (u8 *)&digest); + if (err) { + kunmap_local(virt); + return err; + } + le128_sub(&rctx->rbuf.bignum, &rctx->rbuf.bignum, &digest); + memcpy(virt + bulk_len, &rctx->rbuf.bignum, sizeof(le128)); + kunmap_local(virt); + } else { + /* Slow path that works for any destination scatterlist */ + err = adiantum_hash_message(req, dst, dst_nents, &digest); + if (err) + return err; + le128_sub(&rctx->rbuf.bignum, &rctx->rbuf.bignum, &digest); + scatterwalk_map_and_copy(&rctx->rbuf.bignum, dst, + bulk_len, sizeof(le128), 1); + } return 0; } @@ -324,6 +339,8 @@ static int adiantum_crypt(struct skcipher_request *req, bool enc) const struct adiantum_tfm_ctx *tctx = crypto_skcipher_ctx(tfm); struct adiantum_request_ctx *rctx = skcipher_request_ctx(req); const unsigned int bulk_len = req->cryptlen - BLOCKCIPHER_BLOCK_SIZE; + struct scatterlist *src = req->src; + const unsigned int src_nents = sg_nents(src); unsigned int stream_len; le128 digest; int err; @@ -339,12 +356,24 @@ static int adiantum_crypt(struct skcipher_request *req, bool enc) * dec: C_M = C_R + H_{K_H}(T, C_L) */ adiantum_hash_header(req); - err = adiantum_hash_message(req, req->src, &digest); + rctx->u.hash_desc.tfm = tctx->hash; + if (src_nents == 1 && src->offset + req->cryptlen <= PAGE_SIZE) { + /* Fast path for single-page source */ + void *virt = kmap_local_page(sg_page(src)) + src->offset; + + err = crypto_shash_digest(&rctx->u.hash_desc, virt, bulk_len, + (u8 *)&digest); + memcpy(&rctx->rbuf.bignum, virt + bulk_len, sizeof(le128)); + kunmap_local(virt); + } else { + /* Slow path that works for any source scatterlist */ + err = adiantum_hash_message(req, src, src_nents, &digest); + scatterwalk_map_and_copy(&rctx->rbuf.bignum, src, + bulk_len, sizeof(le128), 0); + } if (err) return err; - le128_add(&digest, &digest, &rctx->header_hash); - scatterwalk_map_and_copy(&rctx->rbuf.bignum, req->src, - bulk_len, BLOCKCIPHER_BLOCK_SIZE, 0); + le128_add(&rctx->rbuf.bignum, &rctx->rbuf.bignum, &rctx->header_hash); le128_add(&rctx->rbuf.bignum, &rctx->rbuf.bignum, &digest); /* If encrypting, encrypt P_M with the block cipher to get C_M */ |