From a5e9f557098e54af44ade5d501379be18435bfbf Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Tue, 11 Sep 2018 20:05:10 -0700 Subject: crypto: chacha20 - Fix chacha20_block() keystream alignment (again) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit In commit 9f480faec58c ("crypto: chacha20 - Fix keystream alignment for chacha20_block()"), I had missed that chacha20_block() can be called directly on the buffer passed to get_random_bytes(), which can have any alignment. So, while my commit didn't break anything, it didn't fully solve the alignment problems. Revert my solution and just update chacha20_block() to use put_unaligned_le32(), so the output buffer need not be aligned. This is simpler, and on many CPUs it's the same speed. But, I kept the 'tmp' buffers in extract_crng_user() and _get_random_bytes() 4-byte aligned, since that alignment is actually needed for _crng_backtrack_protect() too. Reported-by: Stephan Müller Cc: Theodore Ts'o Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu --- include/crypto/chacha20.h | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'include/crypto') diff --git a/include/crypto/chacha20.h b/include/crypto/chacha20.h index b83d66073db0..f76302d99e2b 100644 --- a/include/crypto/chacha20.h +++ b/include/crypto/chacha20.h @@ -13,13 +13,12 @@ #define CHACHA20_IV_SIZE 16 #define CHACHA20_KEY_SIZE 32 #define CHACHA20_BLOCK_SIZE 64 -#define CHACHA20_BLOCK_WORDS (CHACHA20_BLOCK_SIZE / sizeof(u32)) struct chacha20_ctx { u32 key[8]; }; -void chacha20_block(u32 *state, u32 *stream); +void chacha20_block(u32 *state, u8 *stream); void crypto_chacha20_init(u32 *state, struct chacha20_ctx *ctx, u8 *iv); int crypto_chacha20_setkey(struct crypto_skcipher *tfm, const u8 *key, unsigned int keysize); -- cgit