diff options
| -rw-r--r-- | drivers/crypto/inside-secure/safexcel_hash.c | 47 |
1 files changed, 44 insertions, 3 deletions
diff --git a/drivers/crypto/inside-secure/safexcel_hash.c b/drivers/crypto/inside-secure/safexcel_hash.c index 1476574b346e..a777dec5f41f 100644 --- a/drivers/crypto/inside-secure/safexcel_hash.c +++ b/drivers/crypto/inside-secure/safexcel_hash.c @@ -29,6 +29,8 @@ struct safexcel_ahash_req { bool finish; bool hmac; bool needs_inv; + bool hmac_zlen; + bool len_is_le; int nents; dma_addr_t result_dma; @@ -117,7 +119,7 @@ static void safexcel_context_control(struct safexcel_ahash_ctx *ctx, if (req->finish) { /* Compute digest count for hash/HMAC finish operations */ if ((req->digest == CONTEXT_CONTROL_DIGEST_PRECOMPUTED) || - req->processed[1] || + req->hmac_zlen || req->processed[1] || (req->processed[0] != req->block_sz)) { count = req->processed[0] / EIP197_COUNTER_BLOCK_SIZE; count += ((0x100000000ULL / EIP197_COUNTER_BLOCK_SIZE) * @@ -136,6 +138,8 @@ static void safexcel_context_control(struct safexcel_ahash_ctx *ctx, } if ((req->digest == CONTEXT_CONTROL_DIGEST_PRECOMPUTED) || + /* Special case: zero length HMAC */ + req->hmac_zlen || /* PE HW < 4.4 cannot do HMAC continue, fake using hash */ ((req->processed[1] || (req->processed[0] != req->block_sz)))) { @@ -144,11 +148,18 @@ static void safexcel_context_control(struct safexcel_ahash_ctx *ctx, CONTEXT_CONTROL_SIZE((req->state_sz >> 2) + 1) | CONTEXT_CONTROL_TYPE_HASH_OUT | CONTEXT_CONTROL_DIGEST_PRECOMPUTED; + /* For zero-len HMAC, don't finalize, already padded! */ + if (req->hmac_zlen) + cdesc->control_data.control0 |= + CONTEXT_CONTROL_NO_FINISH_HASH; cdesc->control_data.control1 |= CONTEXT_CONTROL_DIGEST_CNT; ctx->base.ctxr->data[req->state_sz >> 2] = cpu_to_le32(count); req->digest = CONTEXT_CONTROL_DIGEST_PRECOMPUTED; + + /* Clear zero-length HMAC flag for next operation! */ + req->hmac_zlen = false; } else { /* HMAC */ /* Need outer digest for HMAC finalization */ memcpy(ctx->base.ctxr->data + (req->state_sz >> 2), @@ -701,8 +712,37 @@ static int safexcel_ahash_final(struct ahash_request *areq) } else if (unlikely(req->hmac && !req->len[1] && (req->len[0] == req->block_sz) && !areq->nbytes)) { - /* TODO: add support for zero length HMAC */ - return 0; + /* + * If we have an overall 0 length *HMAC* request: + * For HMAC, we need to finalize the inner digest + * and then perform the outer hash. + */ + + /* generate pad block in the cache */ + /* start with a hash block of all zeroes */ + memset(req->cache, 0, req->block_sz); + /* set the first byte to 0x80 to 'append a 1 bit' */ + req->cache[0] = 0x80; + /* add the length in bits in the last 2 bytes */ + if (req->len_is_le) { + /* Little endian length word (e.g. MD5) */ + req->cache[req->block_sz-8] = (req->block_sz << 3) & + 255; + req->cache[req->block_sz-7] = (req->block_sz >> 5); + } else { + /* Big endian length word (e.g. any SHA) */ + req->cache[req->block_sz-2] = (req->block_sz >> 5); + req->cache[req->block_sz-1] = (req->block_sz << 3) & + 255; + } + + req->len[0] += req->block_sz; /* plus 1 hash block */ + + /* Set special zero-length HMAC flag */ + req->hmac_zlen = true; + + /* Finalize HMAC */ + req->digest = CONTEXT_CONTROL_DIGEST_HMAC; } else if (req->hmac) { /* Finalize HMAC */ req->digest = CONTEXT_CONTROL_DIGEST_HMAC; @@ -1667,6 +1707,7 @@ static int safexcel_hmac_md5_init(struct ahash_request *areq) req->digest = CONTEXT_CONTROL_DIGEST_PRECOMPUTED; req->state_sz = MD5_DIGEST_SIZE; req->block_sz = MD5_HMAC_BLOCK_SIZE; + req->len_is_le = true; /* MD5 is little endian! ... */ req->hmac = true; return 0; |