crypto: blake2b - merge _final implementation to callback

blake2b_final is called only once, merge it to the crypto API callback
and simplify. This avoids the temporary buffer and swaps the bytes of
internal buffer.

Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/crypto/blake2b_generic.c b/crypto/blake2b_generic.c
index 8dab656..743905f 100644 (file)
--- a/crypto/blake2b_generic.c
+++ b/crypto/blake2b_generic.c
@@ -276,25 +276,6 @@ static void blake2b_update(struct blake2b_state *S, const void *pin, size_t inle
        }
 }
 
-static void blake2b_final(struct blake2b_state *S, void *out, size_t outlen)
-{
-       u8 buffer[BLAKE2B_OUTBYTES] = {0};
-       size_t i;
-
-       blake2b_increment_counter(S, S->buflen);
-       blake2b_set_lastblock(S);
-       /* Padding */
-       memset(S->buf + S->buflen, 0, BLAKE2B_BLOCKBYTES - S->buflen);
-       blake2b_compress(S, S->buf);
-
-       /* Output full hash to temp buffer */
-       for (i = 0; i < 8; ++i)
-               put_unaligned_le64(S->h[i], buffer + sizeof(S->h[i]) * i);
-
-       memcpy(out, buffer, S->outlen);
-       memzero_explicit(buffer, sizeof(buffer));
-}
-
 struct digest_tfm_ctx {
        u8 key[BLAKE2B_KEYBYTES];
        unsigned int keylen;
@@ -338,12 +319,23 @@ static int digest_update(struct shash_desc *desc, const u8 *data,
        return 0;
 }
 
-static int digest_final(struct shash_desc *desc, u8 *out)
+static int blake2b_final(struct shash_desc *desc, u8 *out)
 {
        struct blake2b_state *state = shash_desc_ctx(desc);
        const int digestsize = crypto_shash_digestsize(desc->tfm);
+       size_t i;
+
+       blake2b_increment_counter(state, state->buflen);
+       blake2b_set_lastblock(state);
+       /* Padding */
+       memset(state->buf + state->buflen, 0, BLAKE2B_BLOCKBYTES - state->buflen);
+       blake2b_compress(state, state->buf);
+
+       /* Avoid temporary buffer and switch the internal output to LE order */
+       for (i = 0; i < ARRAY_SIZE(state->h); i++)
+               __cpu_to_le64s(&state->h[i]);
 
-       blake2b_final(state, out, digestsize);
+       memcpy(out, state->h, digestsize);
        return 0;
 }
 
@@ -360,7 +352,7 @@ static struct shash_alg blake2b_algs[] = {
                .setkey                 = digest_setkey,
                .init                   = digest_init,
                .update                 = digest_update,
-               .final                  = digest_final,
+               .final                  = blake2b_final,
                .descsize               = sizeof(struct blake2b_state),
        }, {
                .base.cra_name          = "blake2b-256",
@@ -374,7 +366,7 @@ static struct shash_alg blake2b_algs[] = {
                .setkey                 = digest_setkey,
                .init                   = digest_init,
                .update                 = digest_update,
-               .final                  = digest_final,
+               .final                  = blake2b_final,
                .descsize               = sizeof(struct blake2b_state),
        }, {
                .base.cra_name          = "blake2b-384",
@@ -388,7 +380,7 @@ static struct shash_alg blake2b_algs[] = {
                .setkey                 = digest_setkey,
                .init                   = digest_init,
                .update                 = digest_update,
-               .final                  = digest_final,
+               .final                  = blake2b_final,
                .descsize               = sizeof(struct blake2b_state),
        }, {
                .base.cra_name          = "blake2b-512",
@@ -402,7 +394,7 @@ static struct shash_alg blake2b_algs[] = {
                .setkey                 = digest_setkey,
                .init                   = digest_init,
                .update                 = digest_update,
-               .final                  = digest_final,
+               .final                  = blake2b_final,
                .descsize               = sizeof(struct blake2b_state),
        }
 };