diff options
Diffstat (limited to 'crypto/hctr2.c')
| -rw-r--r-- | crypto/hctr2.c | 226 |
1 files changed, 64 insertions, 162 deletions
diff --git a/crypto/hctr2.c b/crypto/hctr2.c index c8932777bba8..f4cd6c29b4d3 100644 --- a/crypto/hctr2.c +++ b/crypto/hctr2.c @@ -17,7 +17,6 @@ */ #include <crypto/internal/cipher.h> -#include <crypto/internal/hash.h> #include <crypto/internal/skcipher.h> #include <crypto/polyval.h> #include <crypto/scatterwalk.h> @@ -37,23 +36,14 @@ struct hctr2_instance_ctx { struct crypto_cipher_spawn blockcipher_spawn; struct crypto_skcipher_spawn xctr_spawn; - struct crypto_shash_spawn polyval_spawn; }; struct hctr2_tfm_ctx { struct crypto_cipher *blockcipher; struct crypto_skcipher *xctr; - struct crypto_shash *polyval; + struct polyval_key poly_key; + struct polyval_elem hashed_tweaklens[2]; u8 L[BLOCKCIPHER_BLOCK_SIZE]; - int hashed_tweak_offset; - /* - * This struct is allocated with extra space for two exported hash - * states. Since the hash state size is not known at compile-time, we - * can't add these to the struct directly. - * - * hashed_tweaklen_divisible; - * hashed_tweaklen_remainder; - */ }; struct hctr2_request_ctx { @@ -63,39 +53,17 @@ struct hctr2_request_ctx { struct scatterlist *bulk_part_src; struct scatterlist sg_src[2]; struct scatterlist sg_dst[2]; + struct polyval_elem hashed_tweak; /* - * Sub-request sizes are unknown at compile-time, so they need to go - * after the members with known sizes. + * skcipher sub-request size is unknown at compile-time, so it needs to + * go after the members with known sizes. */ union { - struct shash_desc hash_desc; + struct polyval_ctx poly_ctx; struct skcipher_request xctr_req; } u; - /* - * This struct is allocated with extra space for one exported hash - * state. Since the hash state size is not known at compile-time, we - * can't add it to the struct directly. - * - * hashed_tweak; - */ }; -static inline u8 *hctr2_hashed_tweaklen(const struct hctr2_tfm_ctx *tctx, - bool has_remainder) -{ - u8 *p = (u8 *)tctx + sizeof(*tctx); - - if (has_remainder) /* For messages not a multiple of block length */ - p += crypto_shash_statesize(tctx->polyval); - return p; -} - -static inline u8 *hctr2_hashed_tweak(const struct hctr2_tfm_ctx *tctx, - struct hctr2_request_ctx *rctx) -{ - return (u8 *)rctx + tctx->hashed_tweak_offset; -} - /* * The input data for each HCTR2 hash step begins with a 16-byte block that * contains the tweak length and a flag that indicates whether the input is evenly @@ -106,24 +74,23 @@ static inline u8 *hctr2_hashed_tweak(const struct hctr2_tfm_ctx *tctx, * * These precomputed hashes are stored in hctr2_tfm_ctx. */ -static int hctr2_hash_tweaklen(struct hctr2_tfm_ctx *tctx, bool has_remainder) +static void hctr2_hash_tweaklens(struct hctr2_tfm_ctx *tctx) { - SHASH_DESC_ON_STACK(shash, tfm->polyval); - __le64 tweak_length_block[2]; - int err; - - shash->tfm = tctx->polyval; - memset(tweak_length_block, 0, sizeof(tweak_length_block)); - - tweak_length_block[0] = cpu_to_le64(TWEAK_SIZE * 8 * 2 + 2 + has_remainder); - err = crypto_shash_init(shash); - if (err) - return err; - err = crypto_shash_update(shash, (u8 *)tweak_length_block, - POLYVAL_BLOCK_SIZE); - if (err) - return err; - return crypto_shash_export(shash, hctr2_hashed_tweaklen(tctx, has_remainder)); + struct polyval_ctx ctx; + + for (int has_remainder = 0; has_remainder < 2; has_remainder++) { + const __le64 tweak_length_block[2] = { + cpu_to_le64(TWEAK_SIZE * 8 * 2 + 2 + has_remainder), + }; + + polyval_init(&ctx, &tctx->poly_key); + polyval_update(&ctx, (const u8 *)&tweak_length_block, + sizeof(tweak_length_block)); + static_assert(sizeof(tweak_length_block) == POLYVAL_BLOCK_SIZE); + polyval_export_blkaligned( + &ctx, &tctx->hashed_tweaklens[has_remainder]); + } + memzero_explicit(&ctx, sizeof(ctx)); } static int hctr2_setkey(struct crypto_skcipher *tfm, const u8 *key, @@ -156,51 +123,42 @@ static int hctr2_setkey(struct crypto_skcipher *tfm, const u8 *key, tctx->L[0] = 0x01; crypto_cipher_encrypt_one(tctx->blockcipher, tctx->L, tctx->L); - crypto_shash_clear_flags(tctx->polyval, CRYPTO_TFM_REQ_MASK); - crypto_shash_set_flags(tctx->polyval, crypto_skcipher_get_flags(tfm) & - CRYPTO_TFM_REQ_MASK); - err = crypto_shash_setkey(tctx->polyval, hbar, BLOCKCIPHER_BLOCK_SIZE); - if (err) - return err; + static_assert(sizeof(hbar) == POLYVAL_BLOCK_SIZE); + polyval_preparekey(&tctx->poly_key, hbar); memzero_explicit(hbar, sizeof(hbar)); - return hctr2_hash_tweaklen(tctx, true) ?: hctr2_hash_tweaklen(tctx, false); + hctr2_hash_tweaklens(tctx); + return 0; } -static int hctr2_hash_tweak(struct skcipher_request *req) +static void hctr2_hash_tweak(struct skcipher_request *req) { struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); const struct hctr2_tfm_ctx *tctx = crypto_skcipher_ctx(tfm); struct hctr2_request_ctx *rctx = skcipher_request_ctx(req); - struct shash_desc *hash_desc = &rctx->u.hash_desc; - int err; + struct polyval_ctx *poly_ctx = &rctx->u.poly_ctx; bool has_remainder = req->cryptlen % POLYVAL_BLOCK_SIZE; - hash_desc->tfm = tctx->polyval; - err = crypto_shash_import(hash_desc, hctr2_hashed_tweaklen(tctx, has_remainder)); - if (err) - return err; - err = crypto_shash_update(hash_desc, req->iv, TWEAK_SIZE); - if (err) - return err; + polyval_import_blkaligned(poly_ctx, &tctx->poly_key, + &tctx->hashed_tweaklens[has_remainder]); + polyval_update(poly_ctx, req->iv, TWEAK_SIZE); // Store the hashed tweak, since we need it when computing both // H(T || N) and H(T || V). - return crypto_shash_export(hash_desc, hctr2_hashed_tweak(tctx, rctx)); + static_assert(TWEAK_SIZE % POLYVAL_BLOCK_SIZE == 0); + polyval_export_blkaligned(poly_ctx, &rctx->hashed_tweak); } -static int hctr2_hash_message(struct skcipher_request *req, - struct scatterlist *sgl, - u8 digest[POLYVAL_DIGEST_SIZE]) +static void hctr2_hash_message(struct skcipher_request *req, + struct scatterlist *sgl, + u8 digest[POLYVAL_DIGEST_SIZE]) { - static const u8 padding[BLOCKCIPHER_BLOCK_SIZE] = { 0x1 }; + static const u8 padding = 0x1; struct hctr2_request_ctx *rctx = skcipher_request_ctx(req); - struct shash_desc *hash_desc = &rctx->u.hash_desc; + struct polyval_ctx *poly_ctx = &rctx->u.poly_ctx; const unsigned int bulk_len = req->cryptlen - BLOCKCIPHER_BLOCK_SIZE; struct sg_mapping_iter miter; - unsigned int remainder = bulk_len % BLOCKCIPHER_BLOCK_SIZE; int i; - int err = 0; int n = 0; sg_miter_start(&miter, sgl, sg_nents(sgl), @@ -208,22 +166,13 @@ static int hctr2_hash_message(struct skcipher_request *req, for (i = 0; i < bulk_len; i += n) { sg_miter_next(&miter); n = min_t(unsigned int, miter.length, bulk_len - i); - err = crypto_shash_update(hash_desc, miter.addr, n); - if (err) - break; + polyval_update(poly_ctx, miter.addr, n); } sg_miter_stop(&miter); - if (err) - return err; - - if (remainder) { - err = crypto_shash_update(hash_desc, padding, - BLOCKCIPHER_BLOCK_SIZE - remainder); - if (err) - return err; - } - return crypto_shash_final(hash_desc, digest); + if (req->cryptlen % BLOCKCIPHER_BLOCK_SIZE) + polyval_update(poly_ctx, &padding, 1); + polyval_final(poly_ctx, digest); } static int hctr2_finish(struct skcipher_request *req) @@ -231,19 +180,14 @@ static int hctr2_finish(struct skcipher_request *req) struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); const struct hctr2_tfm_ctx *tctx = crypto_skcipher_ctx(tfm); struct hctr2_request_ctx *rctx = skcipher_request_ctx(req); + struct polyval_ctx *poly_ctx = &rctx->u.poly_ctx; u8 digest[POLYVAL_DIGEST_SIZE]; - struct shash_desc *hash_desc = &rctx->u.hash_desc; - int err; // U = UU ^ H(T || V) // or M = MM ^ H(T || N) - hash_desc->tfm = tctx->polyval; - err = crypto_shash_import(hash_desc, hctr2_hashed_tweak(tctx, rctx)); - if (err) - return err; - err = hctr2_hash_message(req, rctx->bulk_part_dst, digest); - if (err) - return err; + polyval_import_blkaligned(poly_ctx, &tctx->poly_key, + &rctx->hashed_tweak); + hctr2_hash_message(req, rctx->bulk_part_dst, digest); crypto_xor(rctx->first_block, digest, BLOCKCIPHER_BLOCK_SIZE); // Copy U (or M) into dst scatterlist @@ -269,7 +213,6 @@ static int hctr2_crypt(struct skcipher_request *req, bool enc) struct hctr2_request_ctx *rctx = skcipher_request_ctx(req); u8 digest[POLYVAL_DIGEST_SIZE]; int bulk_len = req->cryptlen - BLOCKCIPHER_BLOCK_SIZE; - int err; // Requests must be at least one block if (req->cryptlen < BLOCKCIPHER_BLOCK_SIZE) @@ -287,12 +230,8 @@ static int hctr2_crypt(struct skcipher_request *req, bool enc) // MM = M ^ H(T || N) // or UU = U ^ H(T || V) - err = hctr2_hash_tweak(req); - if (err) - return err; - err = hctr2_hash_message(req, rctx->bulk_part_src, digest); - if (err) - return err; + hctr2_hash_tweak(req); + hctr2_hash_message(req, rctx->bulk_part_src, digest); crypto_xor(digest, rctx->first_block, BLOCKCIPHER_BLOCK_SIZE); // UU = E(MM) @@ -338,8 +277,6 @@ static int hctr2_init_tfm(struct crypto_skcipher *tfm) struct hctr2_tfm_ctx *tctx = crypto_skcipher_ctx(tfm); struct crypto_skcipher *xctr; struct crypto_cipher *blockcipher; - struct crypto_shash *polyval; - unsigned int subreq_size; int err; xctr = crypto_spawn_skcipher(&ictx->xctr_spawn); @@ -352,31 +289,17 @@ static int hctr2_init_tfm(struct crypto_skcipher *tfm) goto err_free_xctr; } - polyval = crypto_spawn_shash(&ictx->polyval_spawn); - if (IS_ERR(polyval)) { - err = PTR_ERR(polyval); - goto err_free_blockcipher; - } - tctx->xctr = xctr; tctx->blockcipher = blockcipher; - tctx->polyval = polyval; BUILD_BUG_ON(offsetofend(struct hctr2_request_ctx, u) != sizeof(struct hctr2_request_ctx)); - subreq_size = max(sizeof_field(struct hctr2_request_ctx, u.hash_desc) + - crypto_shash_descsize(polyval), - sizeof_field(struct hctr2_request_ctx, u.xctr_req) + - crypto_skcipher_reqsize(xctr)); - - tctx->hashed_tweak_offset = offsetof(struct hctr2_request_ctx, u) + - subreq_size; - crypto_skcipher_set_reqsize(tfm, tctx->hashed_tweak_offset + - crypto_shash_statesize(polyval)); + crypto_skcipher_set_reqsize( + tfm, max(sizeof(struct hctr2_request_ctx), + offsetofend(struct hctr2_request_ctx, u.xctr_req) + + crypto_skcipher_reqsize(xctr))); return 0; -err_free_blockcipher: - crypto_free_cipher(blockcipher); err_free_xctr: crypto_free_skcipher(xctr); return err; @@ -388,7 +311,6 @@ static void hctr2_exit_tfm(struct crypto_skcipher *tfm) crypto_free_cipher(tctx->blockcipher); crypto_free_skcipher(tctx->xctr); - crypto_free_shash(tctx->polyval); } static void hctr2_free_instance(struct skcipher_instance *inst) @@ -397,21 +319,17 @@ static void hctr2_free_instance(struct skcipher_instance *inst) crypto_drop_cipher(&ictx->blockcipher_spawn); crypto_drop_skcipher(&ictx->xctr_spawn); - crypto_drop_shash(&ictx->polyval_spawn); kfree(inst); } -static int hctr2_create_common(struct crypto_template *tmpl, - struct rtattr **tb, - const char *xctr_name, - const char *polyval_name) +static int hctr2_create_common(struct crypto_template *tmpl, struct rtattr **tb, + const char *xctr_name) { struct skcipher_alg_common *xctr_alg; u32 mask; struct skcipher_instance *inst; struct hctr2_instance_ctx *ictx; struct crypto_alg *blockcipher_alg; - struct shash_alg *polyval_alg; char blockcipher_name[CRYPTO_MAX_ALG_NAME]; int len; int err; @@ -457,19 +375,6 @@ static int hctr2_create_common(struct crypto_template *tmpl, if (blockcipher_alg->cra_blocksize != BLOCKCIPHER_BLOCK_SIZE) goto err_free_inst; - /* Polyval ε-∆U hash function */ - err = crypto_grab_shash(&ictx->polyval_spawn, - skcipher_crypto_instance(inst), - polyval_name, 0, mask); - if (err) - goto err_free_inst; - polyval_alg = crypto_spawn_shash_alg(&ictx->polyval_spawn); - - /* Ensure Polyval is being used */ - err = -EINVAL; - if (strcmp(polyval_alg->base.cra_name, "polyval") != 0) - goto err_free_inst; - /* Instance fields */ err = -ENAMETOOLONG; @@ -477,22 +382,16 @@ static int hctr2_create_common(struct crypto_template *tmpl, blockcipher_alg->cra_name) >= CRYPTO_MAX_ALG_NAME) goto err_free_inst; if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME, - "hctr2_base(%s,%s)", - xctr_alg->base.cra_driver_name, - polyval_alg->base.cra_driver_name) >= CRYPTO_MAX_ALG_NAME) + "hctr2_base(%s,polyval-lib)", + xctr_alg->base.cra_driver_name) >= CRYPTO_MAX_ALG_NAME) goto err_free_inst; inst->alg.base.cra_blocksize = BLOCKCIPHER_BLOCK_SIZE; - inst->alg.base.cra_ctxsize = sizeof(struct hctr2_tfm_ctx) + - polyval_alg->statesize * 2; + inst->alg.base.cra_ctxsize = sizeof(struct hctr2_tfm_ctx); inst->alg.base.cra_alignmask = xctr_alg->base.cra_alignmask; - /* - * The hash function is called twice, so it is weighted higher than the - * xctr and blockcipher. - */ inst->alg.base.cra_priority = (2 * xctr_alg->base.cra_priority + - 4 * polyval_alg->base.cra_priority + - blockcipher_alg->cra_priority) / 7; + blockcipher_alg->cra_priority) / + 3; inst->alg.setkey = hctr2_setkey; inst->alg.encrypt = hctr2_encrypt; @@ -525,8 +424,11 @@ static int hctr2_create_base(struct crypto_template *tmpl, struct rtattr **tb) polyval_name = crypto_attr_alg_name(tb[2]); if (IS_ERR(polyval_name)) return PTR_ERR(polyval_name); + if (strcmp(polyval_name, "polyval") != 0 && + strcmp(polyval_name, "polyval-lib") != 0) + return -ENOENT; - return hctr2_create_common(tmpl, tb, xctr_name, polyval_name); + return hctr2_create_common(tmpl, tb, xctr_name); } static int hctr2_create(struct crypto_template *tmpl, struct rtattr **tb) @@ -542,7 +444,7 @@ static int hctr2_create(struct crypto_template *tmpl, struct rtattr **tb) blockcipher_name) >= CRYPTO_MAX_ALG_NAME) return -ENAMETOOLONG; - return hctr2_create_common(tmpl, tb, xctr_name, "polyval"); + return hctr2_create_common(tmpl, tb, xctr_name); } static struct crypto_template hctr2_tmpls[] = { |
