From a01dc5c1f755899aa23e7e2cfdb146913b18a48c Mon Sep 17 00:00:00 2001 From: Thara Gopinath Date: Thu, 11 Feb 2021 15:01:18 -0500 Subject: [PATCH] crypto: qce - Restore/save ahash state with custom struct in export/import Export and import interfaces save and restore partial transformation states. The partial states were being stored and restored in struct sha1_state for sha1/hmac(sha1) transformations and sha256_state for sha256/hmac(sha256) transformations.This led to a bunch of corner cases where improper state was being stored and restored. A few of the corner cases that turned up during testing are: - wrong byte_count restored if export/import is called twice without h/w transaction in between - wrong buflen restored back if the pending buffer length is exactly the block size. - wrong state restored if buffer length is 0. To fix these issues, save and restore the partial transformation state using the newly introduced qce_sha_saved_state struct. This ensures that all the pieces required to properly restart the transformation is captured and restored back Signed-off-by: Thara Gopinath Signed-off-by: Herbert Xu --- drivers/crypto/qce/sha.c | 122 +++++++++++++---------------------------------- 1 file changed, 34 insertions(+), 88 deletions(-) diff --git a/drivers/crypto/qce/sha.c b/drivers/crypto/qce/sha.c index 61c418c..7da562d 100644 --- a/drivers/crypto/qce/sha.c +++ b/drivers/crypto/qce/sha.c @@ -12,9 +12,15 @@ #include "core.h" #include "sha.h" -/* crypto hw padding constant for first operation */ -#define SHA_PADDING 64 -#define SHA_PADDING_MASK (SHA_PADDING - 1) +struct qce_sha_saved_state { + u8 pending_buf[QCE_SHA_MAX_BLOCKSIZE]; + u8 partial_digest[QCE_SHA_MAX_DIGESTSIZE]; + __be32 byte_count[2]; + unsigned int pending_buflen; + unsigned int flags; + u64 count; + bool first_blk; +}; static LIST_HEAD(ahash_algs); @@ -139,97 +145,37 @@ static int qce_ahash_init(struct ahash_request *req) static int qce_ahash_export(struct ahash_request *req, void *out) { - struct crypto_ahash *ahash = crypto_ahash_reqtfm(req); struct qce_sha_reqctx *rctx = ahash_request_ctx(req); - unsigned long flags = rctx->flags; - unsigned int digestsize = crypto_ahash_digestsize(ahash); - unsigned int blocksize = - crypto_tfm_alg_blocksize(crypto_ahash_tfm(ahash)); - - if (IS_SHA1(flags) || IS_SHA1_HMAC(flags)) { - struct sha1_state *out_state = out; - - out_state->count = rctx->count; - qce_cpu_to_be32p_array((__be32 *)out_state->state, - rctx->digest, digestsize); - memcpy(out_state->buffer, rctx->buf, blocksize); - } else if (IS_SHA256(flags) || IS_SHA256_HMAC(flags)) { - struct sha256_state *out_state = out; - - out_state->count = rctx->count; - qce_cpu_to_be32p_array((__be32 *)out_state->state, - rctx->digest, digestsize); - memcpy(out_state->buf, rctx->buf, blocksize); - } else { - return -EINVAL; - } - - return 0; -} - -static int qce_import_common(struct ahash_request *req, u64 in_count, - const u32 *state, const u8 *buffer, bool hmac) -{ - struct crypto_ahash *ahash = crypto_ahash_reqtfm(req); - struct qce_sha_reqctx *rctx = ahash_request_ctx(req); - unsigned int digestsize = crypto_ahash_digestsize(ahash); - unsigned int blocksize; - u64 count = in_count; - - blocksize = crypto_tfm_alg_blocksize(crypto_ahash_tfm(ahash)); - rctx->count = in_count; - memcpy(rctx->buf, buffer, blocksize); - - if (in_count <= blocksize) { - rctx->first_blk = 1; - } else { - rctx->first_blk = 0; - /* - * For HMAC, there is a hardware padding done when first block - * is set. Therefore the byte_count must be incremened by 64 - * after the first block operation. - */ - if (hmac) - count += SHA_PADDING; - } + struct qce_sha_saved_state *export_state = out; - rctx->byte_count[0] = (__force __be32)(count & ~SHA_PADDING_MASK); - rctx->byte_count[1] = (__force __be32)(count >> 32); - qce_cpu_to_be32p_array((__be32 *)rctx->digest, (const u8 *)state, - digestsize); - rctx->buflen = (unsigned int)(in_count & (blocksize - 1)); + memcpy(export_state->pending_buf, rctx->buf, rctx->buflen); + memcpy(export_state->partial_digest, rctx->digest, sizeof(rctx->digest)); + export_state->byte_count[0] = rctx->byte_count[0]; + export_state->byte_count[1] = rctx->byte_count[1]; + export_state->pending_buflen = rctx->buflen; + export_state->count = rctx->count; + export_state->first_blk = rctx->first_blk; + export_state->flags = rctx->flags; return 0; } static int qce_ahash_import(struct ahash_request *req, const void *in) { - struct qce_sha_reqctx *rctx; - unsigned long flags; - bool hmac; - int ret; - - ret = qce_ahash_init(req); - if (ret) - return ret; - - rctx = ahash_request_ctx(req); - flags = rctx->flags; - hmac = IS_SHA_HMAC(flags); - - if (IS_SHA1(flags) || IS_SHA1_HMAC(flags)) { - const struct sha1_state *state = in; - - ret = qce_import_common(req, state->count, state->state, - state->buffer, hmac); - } else if (IS_SHA256(flags) || IS_SHA256_HMAC(flags)) { - const struct sha256_state *state = in; + struct qce_sha_reqctx *rctx = ahash_request_ctx(req); + const struct qce_sha_saved_state *import_state = in; - ret = qce_import_common(req, state->count, state->state, - state->buf, hmac); - } + memset(rctx, 0, sizeof(*rctx)); + rctx->count = import_state->count; + rctx->buflen = import_state->pending_buflen; + rctx->first_blk = import_state->first_blk; + rctx->flags = import_state->flags; + rctx->byte_count[0] = import_state->byte_count[0]; + rctx->byte_count[1] = import_state->byte_count[1]; + memcpy(rctx->buf, import_state->pending_buf, rctx->buflen); + memcpy(rctx->digest, import_state->partial_digest, sizeof(rctx->digest)); - return ret; + return 0; } static int qce_ahash_update(struct ahash_request *req) @@ -450,7 +396,7 @@ static const struct qce_ahash_def ahash_def[] = { .drv_name = "sha1-qce", .digestsize = SHA1_DIGEST_SIZE, .blocksize = SHA1_BLOCK_SIZE, - .statesize = sizeof(struct sha1_state), + .statesize = sizeof(struct qce_sha_saved_state), .std_iv = std_iv_sha1, }, { @@ -459,7 +405,7 @@ static const struct qce_ahash_def ahash_def[] = { .drv_name = "sha256-qce", .digestsize = SHA256_DIGEST_SIZE, .blocksize = SHA256_BLOCK_SIZE, - .statesize = sizeof(struct sha256_state), + .statesize = sizeof(struct qce_sha_saved_state), .std_iv = std_iv_sha256, }, { @@ -468,7 +414,7 @@ static const struct qce_ahash_def ahash_def[] = { .drv_name = "hmac-sha1-qce", .digestsize = SHA1_DIGEST_SIZE, .blocksize = SHA1_BLOCK_SIZE, - .statesize = sizeof(struct sha1_state), + .statesize = sizeof(struct qce_sha_saved_state), .std_iv = std_iv_sha1, }, { @@ -477,7 +423,7 @@ static const struct qce_ahash_def ahash_def[] = { .drv_name = "hmac-sha256-qce", .digestsize = SHA256_DIGEST_SIZE, .blocksize = SHA256_BLOCK_SIZE, - .statesize = sizeof(struct sha256_state), + .statesize = sizeof(struct qce_sha_saved_state), .std_iv = std_iv_sha256, }, }; -- 2.7.4