From 6e78ad0bb45dd20b3c1a56c72a32e1d82f98b422 Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Mon, 25 Jul 2022 11:36:35 -0700 Subject: crypto: lib - move __crypto_xor into utils 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 Reviewed-by: Jason A. Donenfeld Signed-off-by: Herbert Xu --- lib/crypto/Kconfig | 3 +- lib/crypto/Makefile | 2 +- lib/crypto/memneq.c | 2 -- lib/crypto/utils.c | 88 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 90 insertions(+), 5 deletions(-) create mode 100644 lib/crypto/utils.c (limited to 'lib/crypto') diff --git a/lib/crypto/Kconfig b/lib/crypto/Kconfig index b09d9d6546cb..7e9683e9f5c6 100644 --- a/lib/crypto/Kconfig +++ b/lib/crypto/Kconfig @@ -36,7 +36,7 @@ config CRYPTO_ARCH_HAVE_LIB_CHACHA config CRYPTO_LIB_CHACHA_GENERIC tristate - select XOR_BLOCKS + select CRYPTO_LIB_UTILS help This symbol can be depended upon by arch implementations of the ChaCha library interface that require the generic code as a @@ -46,7 +46,6 @@ config CRYPTO_LIB_CHACHA_GENERIC config CRYPTO_LIB_CHACHA tristate "ChaCha library interface" - depends on CRYPTO depends on CRYPTO_ARCH_HAVE_LIB_CHACHA || !CRYPTO_ARCH_HAVE_LIB_CHACHA select CRYPTO_LIB_CHACHA_GENERIC if CRYPTO_ARCH_HAVE_LIB_CHACHA=n help diff --git a/lib/crypto/Makefile b/lib/crypto/Makefile index b956b3bae26a..c852f067ab06 100644 --- a/lib/crypto/Makefile +++ b/lib/crypto/Makefile @@ -1,7 +1,7 @@ # SPDX-License-Identifier: GPL-2.0 obj-$(CONFIG_CRYPTO_LIB_UTILS) += libcryptoutils.o -libcryptoutils-y := memneq.o +libcryptoutils-y := memneq.o utils.o # chacha is used by the /dev/random driver which is always builtin obj-y += chacha.o diff --git a/lib/crypto/memneq.c b/lib/crypto/memneq.c index f20983184284..d1e8c86fbb0f 100644 --- a/lib/crypto/memneq.c +++ b/lib/crypto/memneq.c @@ -175,5 +175,3 @@ noinline unsigned long __crypto_memneq(const void *a, const void *b, EXPORT_SYMBOL(__crypto_memneq); #endif /* __HAVE_ARCH_CRYPTO_MEMNEQ */ - -MODULE_LICENSE("GPL"); diff --git a/lib/crypto/utils.c b/lib/crypto/utils.c new file mode 100644 index 000000000000..53230ab1b195 --- /dev/null +++ b/lib/crypto/utils.c @@ -0,0 +1,88 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Crypto library utility functions + * + * Copyright (c) 2006 Herbert Xu + */ + +#include +#include +#include + +/* + * 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"); -- cgit