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| author | Ard Biesheuvel <ard.biesheuvel@linaro.org> | 2017-07-24 11:28:04 +0100 |
|---|---|---|
| committer | Herbert Xu <herbert@gondor.apana.org.au> | 2017-08-04 09:27:15 +0800 |
| commit | 45fe93dff2fb58b22de04c729f8447ba0f773d93 (patch) | |
| tree | 6f6039696f88fb5461831d4bfbc4e62f059092d5 /crypto | |
| parent | a7c391f04fe3259fb0417d71fec78ae28f25780e (diff) | |
| download | lwn-45fe93dff2fb58b22de04c729f8447ba0f773d93.tar.gz lwn-45fe93dff2fb58b22de04c729f8447ba0f773d93.zip | |
crypto: algapi - make crypto_xor() take separate dst and src arguments
There are quite a number of occurrences in the kernel of the pattern
if (dst != src)
memcpy(dst, src, walk.total % AES_BLOCK_SIZE);
crypto_xor(dst, final, walk.total % AES_BLOCK_SIZE);
or
crypto_xor(keystream, src, nbytes);
memcpy(dst, keystream, nbytes);
where crypto_xor() is preceded or followed by a memcpy() invocation
that is only there because crypto_xor() uses its output parameter as
one of the inputs. To avoid having to add new instances of this pattern
in the arm64 code, which will be refactored to implement non-SIMD
fallbacks, add an alternative implementation called crypto_xor_cpy(),
taking separate input and output arguments. This removes the need for
the separate memcpy().
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'crypto')
| -rw-r--r-- | crypto/ctr.c | 3 | ||||
| -rw-r--r-- | crypto/pcbc.c | 12 |
2 files changed, 5 insertions, 10 deletions
diff --git a/crypto/ctr.c b/crypto/ctr.c index 477d9226ccaa..854d924f9d8e 100644 --- a/crypto/ctr.c +++ b/crypto/ctr.c @@ -65,8 +65,7 @@ static void crypto_ctr_crypt_final(struct blkcipher_walk *walk, unsigned int nbytes = walk->nbytes; crypto_cipher_encrypt_one(tfm, keystream, ctrblk); - crypto_xor(keystream, src, nbytes); - memcpy(dst, keystream, nbytes); + crypto_xor_cpy(dst, keystream, src, nbytes); crypto_inc(ctrblk, bsize); } diff --git a/crypto/pcbc.c b/crypto/pcbc.c index 29dd2b4a3b85..d9e45a958720 100644 --- a/crypto/pcbc.c +++ b/crypto/pcbc.c @@ -55,8 +55,7 @@ static int crypto_pcbc_encrypt_segment(struct skcipher_request *req, do { crypto_xor(iv, src, bsize); crypto_cipher_encrypt_one(tfm, dst, iv); - memcpy(iv, dst, bsize); - crypto_xor(iv, src, bsize); + crypto_xor_cpy(iv, dst, src, bsize); src += bsize; dst += bsize; @@ -79,8 +78,7 @@ static int crypto_pcbc_encrypt_inplace(struct skcipher_request *req, memcpy(tmpbuf, src, bsize); crypto_xor(iv, src, bsize); crypto_cipher_encrypt_one(tfm, src, iv); - memcpy(iv, tmpbuf, bsize); - crypto_xor(iv, src, bsize); + crypto_xor_cpy(iv, tmpbuf, src, bsize); src += bsize; } while ((nbytes -= bsize) >= bsize); @@ -127,8 +125,7 @@ static int crypto_pcbc_decrypt_segment(struct skcipher_request *req, do { crypto_cipher_decrypt_one(tfm, dst, src); crypto_xor(dst, iv, bsize); - memcpy(iv, src, bsize); - crypto_xor(iv, dst, bsize); + crypto_xor_cpy(iv, dst, src, bsize); src += bsize; dst += bsize; @@ -153,8 +150,7 @@ static int crypto_pcbc_decrypt_inplace(struct skcipher_request *req, memcpy(tmpbuf, src, bsize); crypto_cipher_decrypt_one(tfm, src, src); crypto_xor(src, iv, bsize); - memcpy(iv, tmpbuf, bsize); - crypto_xor(iv, src, bsize); + crypto_xor_cpy(iv, src, tmpbuf, bsize); src += bsize; } while ((nbytes -= bsize) >= bsize); |