diff options
| author | Ryan Wanner <Ryan.Wanner@microchip.com> | 2023-03-28 12:56:26 -0700 |
|---|---|---|
| committer | Herbert Xu <herbert@gondor.apana.org.au> | 2023-04-06 16:41:28 +0800 |
| commit | 232c1e8e19ff8e60237012fadead02557aafca5a (patch) | |
| tree | 0362b66282a5a637c74c0e47a79a4ebdb19cb524 | |
| parent | a4b16dad46576ce08ecb660fc923d0857dcae107 (diff) | |
crypto: atmel-sha - Add zero length message digest support for hmac
Add softare padding to hmac-sha digest for zero length messages.
Using the atmel_sha_fill_padding() to fill the buffer with a padded
empty message with a length of the block size.
Create a temporary scatter list from the padded buffer to pass into the
data processing functions.
Signed-off-by: Ryan Wanner <Ryan.Wanner@microchip.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
| -rw-r--r-- | drivers/crypto/atmel-sha.c | 34 |
1 files changed, 30 insertions, 4 deletions
diff --git a/drivers/crypto/atmel-sha.c b/drivers/crypto/atmel-sha.c index e7c1db2739ec..6bef634d3c86 100644 --- a/drivers/crypto/atmel-sha.c +++ b/drivers/crypto/atmel-sha.c @@ -1948,14 +1948,32 @@ static int atmel_sha_hmac_digest2(struct atmel_sha_dev *dd) struct atmel_sha_reqctx *ctx = ahash_request_ctx(req); struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); struct atmel_sha_hmac_ctx *hmac = crypto_ahash_ctx(tfm); + struct scatterlist *sgbuf; size_t hs = ctx->hash_size; size_t i, num_words = hs / sizeof(u32); bool use_dma = false; u32 mr; /* Special case for empty message. */ - if (!req->nbytes) - return atmel_sha_complete(dd, -EINVAL); // TODO: + if (!req->nbytes) { + req->nbytes = 0; + ctx->bufcnt = 0; + ctx->digcnt[0] = 0; + ctx->digcnt[1] = 0; + switch (ctx->flags & SHA_FLAGS_ALGO_MASK) { + case SHA_FLAGS_SHA1: + case SHA_FLAGS_SHA224: + case SHA_FLAGS_SHA256: + atmel_sha_fill_padding(ctx, 64); + break; + + case SHA_FLAGS_SHA384: + case SHA_FLAGS_SHA512: + atmel_sha_fill_padding(ctx, 128); + break; + } + sg_init_one(&dd->tmp, ctx->buffer, ctx->bufcnt); + } /* Check DMA threshold and alignment. */ if (req->nbytes > ATMEL_SHA_DMA_THRESHOLD && @@ -1985,12 +2003,20 @@ static int atmel_sha_hmac_digest2(struct atmel_sha_dev *dd) atmel_sha_write(dd, SHA_CR, SHA_CR_FIRST); + /* Special case for empty message. */ + if (!req->nbytes) { + sgbuf = &dd->tmp; + req->nbytes = ctx->bufcnt; + } else { + sgbuf = req->src; + } + /* Process data. */ if (use_dma) - return atmel_sha_dma_start(dd, req->src, req->nbytes, + return atmel_sha_dma_start(dd, sgbuf, req->nbytes, atmel_sha_hmac_final_done); - return atmel_sha_cpu_start(dd, req->src, req->nbytes, false, true, + return atmel_sha_cpu_start(dd, sgbuf, req->nbytes, false, true, atmel_sha_hmac_final_done); } |