linux/crypto/blake2s_generic.c

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// SPDX-License-Identifier: GPL-2.0 OR MIT
/*
crypto: blake2s - share the "shash" API boilerplate code Add helper functions for shash implementations of BLAKE2s to include/crypto/internal/blake2s.h, taking advantage of __blake2s_update() and __blake2s_final() that were added by the previous patch to share more code between the library and shash implementations. crypto_blake2s_setkey() and crypto_blake2s_init() are usable as shash_alg::setkey and shash_alg::init directly, while crypto_blake2s_update() and crypto_blake2s_final() take an extra 'blake2s_compress_t' function pointer parameter. This allows the implementation of the compression function to be overridden, which is the only part that optimized implementations really care about. The new functions are inline functions (similar to those in sha1_base.h, sha256_base.h, and sm3_base.h) because this avoids needing to add a new module blake2s_helpers.ko, they aren't *too* long, and this avoids indirect calls which are expensive these days. Note that they can't go in blake2s_generic.ko, as that would require selecting CRYPTO_BLAKE2S from CRYPTO_BLAKE2S_X86, which would cause a recursive dependency. Finally, use these new helper functions in the x86 implementation of BLAKE2s. (This part should be a separate patch, but unfortunately the x86 implementation used the exact same function names like "crypto_blake2s_update()", so it had to be updated at the same time.) Signed-off-by: Eric Biggers <ebiggers@google.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-12-23 08:09:54 +00:00
* shash interface to the generic implementation of BLAKE2s
*
* Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
*/
#include <crypto/internal/blake2s.h>
#include <crypto/internal/hash.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/module.h>
crypto: blake2s - share the "shash" API boilerplate code Add helper functions for shash implementations of BLAKE2s to include/crypto/internal/blake2s.h, taking advantage of __blake2s_update() and __blake2s_final() that were added by the previous patch to share more code between the library and shash implementations. crypto_blake2s_setkey() and crypto_blake2s_init() are usable as shash_alg::setkey and shash_alg::init directly, while crypto_blake2s_update() and crypto_blake2s_final() take an extra 'blake2s_compress_t' function pointer parameter. This allows the implementation of the compression function to be overridden, which is the only part that optimized implementations really care about. The new functions are inline functions (similar to those in sha1_base.h, sha256_base.h, and sm3_base.h) because this avoids needing to add a new module blake2s_helpers.ko, they aren't *too* long, and this avoids indirect calls which are expensive these days. Note that they can't go in blake2s_generic.ko, as that would require selecting CRYPTO_BLAKE2S from CRYPTO_BLAKE2S_X86, which would cause a recursive dependency. Finally, use these new helper functions in the x86 implementation of BLAKE2s. (This part should be a separate patch, but unfortunately the x86 implementation used the exact same function names like "crypto_blake2s_update()", so it had to be updated at the same time.) Signed-off-by: Eric Biggers <ebiggers@google.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-12-23 08:09:54 +00:00
static int crypto_blake2s_update_generic(struct shash_desc *desc,
const u8 *in, unsigned int inlen)
{
lib/crypto: blake2s: avoid indirect calls to compression function for Clang CFI blake2s_compress_generic is weakly aliased by blake2s_compress. The current harness for function selection uses a function pointer, which is ordinarily inlined and resolved at compile time. But when Clang's CFI is enabled, CFI still triggers when making an indirect call via a weak symbol. This seems like a bug in Clang's CFI, as though it's bucketing weak symbols and strong symbols differently. It also only seems to trigger when "full LTO" mode is used, rather than "thin LTO". [ 0.000000][ T0] Kernel panic - not syncing: CFI failure (target: blake2s_compress_generic+0x0/0x1444) [ 0.000000][ T0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.16.0-mainline-06981-g076c855b846e #1 [ 0.000000][ T0] Hardware name: MT6873 (DT) [ 0.000000][ T0] Call trace: [ 0.000000][ T0] dump_backtrace+0xfc/0x1dc [ 0.000000][ T0] dump_stack_lvl+0xa8/0x11c [ 0.000000][ T0] panic+0x194/0x464 [ 0.000000][ T0] __cfi_check_fail+0x54/0x58 [ 0.000000][ T0] __cfi_slowpath_diag+0x354/0x4b0 [ 0.000000][ T0] blake2s_update+0x14c/0x178 [ 0.000000][ T0] _extract_entropy+0xf4/0x29c [ 0.000000][ T0] crng_initialize_primary+0x24/0x94 [ 0.000000][ T0] rand_initialize+0x2c/0x6c [ 0.000000][ T0] start_kernel+0x2f8/0x65c [ 0.000000][ T0] __primary_switched+0xc4/0x7be4 [ 0.000000][ T0] Rebooting in 5 seconds.. Nonetheless, the function pointer method isn't so terrific anyway, so this patch replaces it with a simple boolean, which also gets inlined away. This successfully works around the Clang bug. In general, I'm not too keen on all of the indirection involved here; it clearly does more harm than good. Hopefully the whole thing can get cleaned up down the road when lib/crypto is overhauled more comprehensively. But for now, we go with a simple bandaid. Fixes: 6048fdcc5f26 ("lib/crypto: blake2s: include as built-in") Link: https://github.com/ClangBuiltLinux/linux/issues/1567 Reported-by: Miles Chen <miles.chen@mediatek.com> Tested-by: Miles Chen <miles.chen@mediatek.com> Tested-by: Nathan Chancellor <nathan@kernel.org> Tested-by: John Stultz <john.stultz@linaro.org> Acked-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-01-19 13:35:06 +00:00
return crypto_blake2s_update(desc, in, inlen, true);
}
crypto: blake2s - share the "shash" API boilerplate code Add helper functions for shash implementations of BLAKE2s to include/crypto/internal/blake2s.h, taking advantage of __blake2s_update() and __blake2s_final() that were added by the previous patch to share more code between the library and shash implementations. crypto_blake2s_setkey() and crypto_blake2s_init() are usable as shash_alg::setkey and shash_alg::init directly, while crypto_blake2s_update() and crypto_blake2s_final() take an extra 'blake2s_compress_t' function pointer parameter. This allows the implementation of the compression function to be overridden, which is the only part that optimized implementations really care about. The new functions are inline functions (similar to those in sha1_base.h, sha256_base.h, and sm3_base.h) because this avoids needing to add a new module blake2s_helpers.ko, they aren't *too* long, and this avoids indirect calls which are expensive these days. Note that they can't go in blake2s_generic.ko, as that would require selecting CRYPTO_BLAKE2S from CRYPTO_BLAKE2S_X86, which would cause a recursive dependency. Finally, use these new helper functions in the x86 implementation of BLAKE2s. (This part should be a separate patch, but unfortunately the x86 implementation used the exact same function names like "crypto_blake2s_update()", so it had to be updated at the same time.) Signed-off-by: Eric Biggers <ebiggers@google.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-12-23 08:09:54 +00:00
static int crypto_blake2s_final_generic(struct shash_desc *desc, u8 *out)
{
lib/crypto: blake2s: avoid indirect calls to compression function for Clang CFI blake2s_compress_generic is weakly aliased by blake2s_compress. The current harness for function selection uses a function pointer, which is ordinarily inlined and resolved at compile time. But when Clang's CFI is enabled, CFI still triggers when making an indirect call via a weak symbol. This seems like a bug in Clang's CFI, as though it's bucketing weak symbols and strong symbols differently. It also only seems to trigger when "full LTO" mode is used, rather than "thin LTO". [ 0.000000][ T0] Kernel panic - not syncing: CFI failure (target: blake2s_compress_generic+0x0/0x1444) [ 0.000000][ T0] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.16.0-mainline-06981-g076c855b846e #1 [ 0.000000][ T0] Hardware name: MT6873 (DT) [ 0.000000][ T0] Call trace: [ 0.000000][ T0] dump_backtrace+0xfc/0x1dc [ 0.000000][ T0] dump_stack_lvl+0xa8/0x11c [ 0.000000][ T0] panic+0x194/0x464 [ 0.000000][ T0] __cfi_check_fail+0x54/0x58 [ 0.000000][ T0] __cfi_slowpath_diag+0x354/0x4b0 [ 0.000000][ T0] blake2s_update+0x14c/0x178 [ 0.000000][ T0] _extract_entropy+0xf4/0x29c [ 0.000000][ T0] crng_initialize_primary+0x24/0x94 [ 0.000000][ T0] rand_initialize+0x2c/0x6c [ 0.000000][ T0] start_kernel+0x2f8/0x65c [ 0.000000][ T0] __primary_switched+0xc4/0x7be4 [ 0.000000][ T0] Rebooting in 5 seconds.. Nonetheless, the function pointer method isn't so terrific anyway, so this patch replaces it with a simple boolean, which also gets inlined away. This successfully works around the Clang bug. In general, I'm not too keen on all of the indirection involved here; it clearly does more harm than good. Hopefully the whole thing can get cleaned up down the road when lib/crypto is overhauled more comprehensively. But for now, we go with a simple bandaid. Fixes: 6048fdcc5f26 ("lib/crypto: blake2s: include as built-in") Link: https://github.com/ClangBuiltLinux/linux/issues/1567 Reported-by: Miles Chen <miles.chen@mediatek.com> Tested-by: Miles Chen <miles.chen@mediatek.com> Tested-by: Nathan Chancellor <nathan@kernel.org> Tested-by: John Stultz <john.stultz@linaro.org> Acked-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-01-19 13:35:06 +00:00
return crypto_blake2s_final(desc, out, true);
}
#define BLAKE2S_ALG(name, driver_name, digest_size) \
{ \
.base.cra_name = name, \
.base.cra_driver_name = driver_name, \
.base.cra_priority = 100, \
.base.cra_flags = CRYPTO_ALG_OPTIONAL_KEY, \
.base.cra_blocksize = BLAKE2S_BLOCK_SIZE, \
.base.cra_ctxsize = sizeof(struct blake2s_tfm_ctx), \
.base.cra_module = THIS_MODULE, \
.digestsize = digest_size, \
.setkey = crypto_blake2s_setkey, \
.init = crypto_blake2s_init, \
crypto: blake2s - share the "shash" API boilerplate code Add helper functions for shash implementations of BLAKE2s to include/crypto/internal/blake2s.h, taking advantage of __blake2s_update() and __blake2s_final() that were added by the previous patch to share more code between the library and shash implementations. crypto_blake2s_setkey() and crypto_blake2s_init() are usable as shash_alg::setkey and shash_alg::init directly, while crypto_blake2s_update() and crypto_blake2s_final() take an extra 'blake2s_compress_t' function pointer parameter. This allows the implementation of the compression function to be overridden, which is the only part that optimized implementations really care about. The new functions are inline functions (similar to those in sha1_base.h, sha256_base.h, and sm3_base.h) because this avoids needing to add a new module blake2s_helpers.ko, they aren't *too* long, and this avoids indirect calls which are expensive these days. Note that they can't go in blake2s_generic.ko, as that would require selecting CRYPTO_BLAKE2S from CRYPTO_BLAKE2S_X86, which would cause a recursive dependency. Finally, use these new helper functions in the x86 implementation of BLAKE2s. (This part should be a separate patch, but unfortunately the x86 implementation used the exact same function names like "crypto_blake2s_update()", so it had to be updated at the same time.) Signed-off-by: Eric Biggers <ebiggers@google.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-12-23 08:09:54 +00:00
.update = crypto_blake2s_update_generic, \
.final = crypto_blake2s_final_generic, \
.descsize = sizeof(struct blake2s_state), \
}
static struct shash_alg blake2s_algs[] = {
BLAKE2S_ALG("blake2s-128", "blake2s-128-generic",
BLAKE2S_128_HASH_SIZE),
BLAKE2S_ALG("blake2s-160", "blake2s-160-generic",
BLAKE2S_160_HASH_SIZE),
BLAKE2S_ALG("blake2s-224", "blake2s-224-generic",
BLAKE2S_224_HASH_SIZE),
BLAKE2S_ALG("blake2s-256", "blake2s-256-generic",
BLAKE2S_256_HASH_SIZE),
};
static int __init blake2s_mod_init(void)
{
return crypto_register_shashes(blake2s_algs, ARRAY_SIZE(blake2s_algs));
}
static void __exit blake2s_mod_exit(void)
{
crypto_unregister_shashes(blake2s_algs, ARRAY_SIZE(blake2s_algs));
}
subsys_initcall(blake2s_mod_init);
module_exit(blake2s_mod_exit);
MODULE_ALIAS_CRYPTO("blake2s-128");
MODULE_ALIAS_CRYPTO("blake2s-128-generic");
MODULE_ALIAS_CRYPTO("blake2s-160");
MODULE_ALIAS_CRYPTO("blake2s-160-generic");
MODULE_ALIAS_CRYPTO("blake2s-224");
MODULE_ALIAS_CRYPTO("blake2s-224-generic");
MODULE_ALIAS_CRYPTO("blake2s-256");
MODULE_ALIAS_CRYPTO("blake2s-256-generic");
MODULE_LICENSE("GPL v2");