crypto: chacha-generic - use crypto_xor_cpy()

In chacha_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>
This commit is contained in:
Eric Biggers 2019-03-14 21:20:36 -07:00 committed by Herbert Xu
parent dcf7b48212
commit 29d97dec22

View File

@ -22,18 +22,16 @@ static void chacha_docrypt(u32 *state, u8 *dst, const u8 *src,
/* aligned to potentially speed up crypto_xor() */
u8 stream[CHACHA_BLOCK_SIZE] __aligned(sizeof(long));
if (dst != src)
memcpy(dst, src, bytes);
while (bytes >= CHACHA_BLOCK_SIZE) {
chacha_block(state, stream, nrounds);
crypto_xor(dst, stream, CHACHA_BLOCK_SIZE);
crypto_xor_cpy(dst, src, stream, CHACHA_BLOCK_SIZE);
bytes -= CHACHA_BLOCK_SIZE;
dst += CHACHA_BLOCK_SIZE;
src += CHACHA_BLOCK_SIZE;
}
if (bytes) {
chacha_block(state, stream, nrounds);
crypto_xor(dst, stream, bytes);
crypto_xor_cpy(dst, src, stream, bytes);
}
}