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authorArd Biesheuvel <ard.biesheuvel@linaro.org>2017-07-24 13:28:04 +0300
committerHerbert Xu <herbert@gondor.apana.org.au>2017-08-04 04:27:15 +0300
commit45fe93dff2fb58b22de04c729f8447ba0f773d93 (patch)
tree6f6039696f88fb5461831d4bfbc4e62f059092d5 /include/crypto/algapi.h
parenta7c391f04fe3259fb0417d71fec78ae28f25780e (diff)
downloadlinux-45fe93dff2fb58b22de04c729f8447ba0f773d93.tar.xz
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 'include/crypto/algapi.h')
-rw-r--r--include/crypto/algapi.h19
1 files changed, 19 insertions, 0 deletions
diff --git a/include/crypto/algapi.h b/include/crypto/algapi.h
index fd547f946bf8..e3cebf640c00 100644
--- a/include/crypto/algapi.h
+++ b/include/crypto/algapi.h
@@ -211,6 +211,25 @@ static inline void crypto_xor(u8 *dst, const u8 *src, unsigned int size)
}
}
+static inline void crypto_xor_cpy(u8 *dst, const u8 *src1, const u8 *src2,
+ unsigned int size)
+{
+ if (IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) &&
+ __builtin_constant_p(size) &&
+ (size % sizeof(unsigned long)) == 0) {
+ unsigned long *d = (unsigned long *)dst;
+ unsigned long *s1 = (unsigned long *)src1;
+ unsigned long *s2 = (unsigned long *)src2;
+
+ while (size > 0) {
+ *d++ = *s1++ ^ *s2++;
+ size -= sizeof(unsigned long);
+ }
+ } else {
+ __crypto_xor(dst, src1, src2, size);
+ }
+}
+
int blkcipher_walk_done(struct blkcipher_desc *desc,
struct blkcipher_walk *walk, int err);
int blkcipher_walk_virt(struct blkcipher_desc *desc,