forked from Minki/linux
6e78ad0bb4
CRYPTO_LIB_CHACHA depends on CRYPTO for __crypto_xor, defined in crypto/algapi.c. This is a layering violation because the dependencies should only go in the other direction (crypto/ => lib/crypto/). Also the correct dependency would be CRYPTO_ALGAPI, not CRYPTO. Fix this by moving __crypto_xor into the utils module in lib/crypto/. Note that CRYPTO_LIB_CHACHA_GENERIC selected XOR_BLOCKS, which is unrelated and unnecessary. It was perhaps thought that XOR_BLOCKS was needed for __crypto_xor, but that's not the case. Signed-off-by: Eric Biggers <ebiggers@google.com> Reviewed-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
89 lines
2.2 KiB
C
89 lines
2.2 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/*
|
|
* Crypto library utility functions
|
|
*
|
|
* Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
|
|
*/
|
|
|
|
#include <asm/unaligned.h>
|
|
#include <crypto/algapi.h>
|
|
#include <linux/module.h>
|
|
|
|
/*
|
|
* XOR @len bytes from @src1 and @src2 together, writing the result to @dst
|
|
* (which may alias one of the sources). Don't call this directly; call
|
|
* crypto_xor() or crypto_xor_cpy() instead.
|
|
*/
|
|
void __crypto_xor(u8 *dst, const u8 *src1, const u8 *src2, unsigned int len)
|
|
{
|
|
int relalign = 0;
|
|
|
|
if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)) {
|
|
int size = sizeof(unsigned long);
|
|
int d = (((unsigned long)dst ^ (unsigned long)src1) |
|
|
((unsigned long)dst ^ (unsigned long)src2)) &
|
|
(size - 1);
|
|
|
|
relalign = d ? 1 << __ffs(d) : size;
|
|
|
|
/*
|
|
* If we care about alignment, process as many bytes as
|
|
* needed to advance dst and src to values whose alignments
|
|
* equal their relative alignment. This will allow us to
|
|
* process the remainder of the input using optimal strides.
|
|
*/
|
|
while (((unsigned long)dst & (relalign - 1)) && len > 0) {
|
|
*dst++ = *src1++ ^ *src2++;
|
|
len--;
|
|
}
|
|
}
|
|
|
|
while (IS_ENABLED(CONFIG_64BIT) && len >= 8 && !(relalign & 7)) {
|
|
if (IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)) {
|
|
u64 l = get_unaligned((u64 *)src1) ^
|
|
get_unaligned((u64 *)src2);
|
|
put_unaligned(l, (u64 *)dst);
|
|
} else {
|
|
*(u64 *)dst = *(u64 *)src1 ^ *(u64 *)src2;
|
|
}
|
|
dst += 8;
|
|
src1 += 8;
|
|
src2 += 8;
|
|
len -= 8;
|
|
}
|
|
|
|
while (len >= 4 && !(relalign & 3)) {
|
|
if (IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)) {
|
|
u32 l = get_unaligned((u32 *)src1) ^
|
|
get_unaligned((u32 *)src2);
|
|
put_unaligned(l, (u32 *)dst);
|
|
} else {
|
|
*(u32 *)dst = *(u32 *)src1 ^ *(u32 *)src2;
|
|
}
|
|
dst += 4;
|
|
src1 += 4;
|
|
src2 += 4;
|
|
len -= 4;
|
|
}
|
|
|
|
while (len >= 2 && !(relalign & 1)) {
|
|
if (IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)) {
|
|
u16 l = get_unaligned((u16 *)src1) ^
|
|
get_unaligned((u16 *)src2);
|
|
put_unaligned(l, (u16 *)dst);
|
|
} else {
|
|
*(u16 *)dst = *(u16 *)src1 ^ *(u16 *)src2;
|
|
}
|
|
dst += 2;
|
|
src1 += 2;
|
|
src2 += 2;
|
|
len -= 2;
|
|
}
|
|
|
|
while (len--)
|
|
*dst++ = *src1++ ^ *src2++;
|
|
}
|
|
EXPORT_SYMBOL_GPL(__crypto_xor);
|
|
|
|
MODULE_LICENSE("GPL");
|