crypto: salsa20-generic - use crypto_xor_cpy()
authorEric Biggers <ebiggers@google.com>
Fri, 15 Mar 2019 04:21:28 +0000 (21:21 -0700)
committerHerbert Xu <herbert@gondor.apana.org.au>
Fri, 22 Mar 2019 12:57:28 +0000 (20:57 +0800)
In salsa20_docrypt(), use crypto_xor_cpy() instead of crypto_xor().
This avoids having to memcpy() the src buffer to the dst buffer.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
crypto/salsa20_generic.c

index 00fce32ae17af9fa630db24e2ff2ee4f8b7bf547..443fba09cbed723da18639545e3811a7bc18c0bf 100644 (file)
@@ -86,18 +86,17 @@ static void salsa20_docrypt(u32 *state, u8 *dst, const u8 *src,
 {
        __le32 stream[SALSA20_BLOCK_SIZE / sizeof(__le32)];
 
-       if (dst != src)
-               memcpy(dst, src, bytes);
-
        while (bytes >= SALSA20_BLOCK_SIZE) {
                salsa20_block(state, stream);
-               crypto_xor(dst, (const u8 *)stream, SALSA20_BLOCK_SIZE);
+               crypto_xor_cpy(dst, src, (const u8 *)stream,
+                              SALSA20_BLOCK_SIZE);
                bytes -= SALSA20_BLOCK_SIZE;
                dst += SALSA20_BLOCK_SIZE;
+               src += SALSA20_BLOCK_SIZE;
        }
        if (bytes) {
                salsa20_block(state, stream);
-               crypto_xor(dst, (const u8 *)stream, bytes);
+               crypto_xor_cpy(dst, src, (const u8 *)stream, bytes);
        }
 }