[PATCH] crypto: salsa20-generic - use crypto_xor_cpy()

[Eric Biggers]

From: Eric Biggers <ebigg...@google.com>

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 <ebigg...@google.com>
---
 crypto/salsa20_generic.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/crypto/salsa20_generic.c b/crypto/salsa20_generic.c
index 00fce32ae17a..443fba09cbed 100644
--- a/crypto/salsa20_generic.c
+++ b/crypto/salsa20_generic.c
@@ -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);
        }
 }
 
-- 
2.21.0