diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2025-09-29 15:48:56 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2025-09-29 15:48:56 -0700 |
commit | d8768fb12a14c30436bd0466b4fc28edeef45078 (patch) | |
tree | 49ceb107f33d3988a9f74267fb0c77f22b915904 /lib/crypto/chacha.c | |
parent | e2fffe1d958b3660bc4e07e6542d97b6cc168826 (diff) | |
parent | b94bc4398beccd329a51052c5e7e84e4670dbcd9 (diff) |
Merge tag 'libcrypto-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux
Pull crypto library updates from Eric Biggers:
- Add a RISC-V optimized implementation of Poly1305. This code was
written by Andy Polyakov and contributed by Zhihang Shao.
- Migrate the MD5 code into lib/crypto/, and add KUnit tests for MD5.
Yes, it's still the 90s, and several kernel subsystems are still
using MD5 for legacy use cases. As long as that remains the case,
it's helpful to clean it up in the same way as I've been doing for
other algorithms.
Later, I plan to convert most of these users of MD5 to use the new
MD5 library API instead of the generic crypto API.
- Simplify the organization of the ChaCha, Poly1305, BLAKE2s, and
Curve25519 code.
Consolidate these into one module per algorithm, and centralize the
configuration and build process. This is the same reorganization that
has already been successful for SHA-1 and SHA-2.
- Remove the unused crypto_kpp API for Curve25519.
- Migrate the BLAKE2s and Curve25519 self-tests to KUnit.
- Always enable the architecture-optimized BLAKE2s code.
* tag 'libcrypto-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux: (38 commits)
crypto: md5 - Implement export_core() and import_core()
wireguard: kconfig: simplify crypto kconfig selections
lib/crypto: tests: Enable Curve25519 test when CRYPTO_SELFTESTS
lib/crypto: curve25519: Consolidate into single module
lib/crypto: curve25519: Move a couple functions out-of-line
lib/crypto: tests: Add Curve25519 benchmark
lib/crypto: tests: Migrate Curve25519 self-test to KUnit
crypto: curve25519 - Remove unused kpp support
crypto: testmgr - Remove curve25519 kpp tests
crypto: x86/curve25519 - Remove unused kpp support
crypto: powerpc/curve25519 - Remove unused kpp support
crypto: arm/curve25519 - Remove unused kpp support
crypto: hisilicon/hpre - Remove unused curve25519 kpp support
lib/crypto: tests: Add KUnit tests for BLAKE2s
lib/crypto: blake2s: Consolidate into single C translation unit
lib/crypto: blake2s: Move generic code into blake2s.c
lib/crypto: blake2s: Always enable arch-optimized BLAKE2s code
lib/crypto: blake2s: Remove obsolete self-test
lib/crypto: x86/blake2s: Reduce size of BLAKE2S_SIGMA2
lib/crypto: chacha: Consolidate into single module
...
Diffstat (limited to 'lib/crypto/chacha.c')
-rw-r--r-- | lib/crypto/chacha.c | 142 |
1 files changed, 49 insertions, 93 deletions
diff --git a/lib/crypto/chacha.c b/lib/crypto/chacha.c index 77f68de71066..e0c7cb4af318 100644 --- a/lib/crypto/chacha.c +++ b/lib/crypto/chacha.c @@ -1,114 +1,70 @@ // SPDX-License-Identifier: GPL-2.0-or-later /* - * The "hash function" used as the core of the ChaCha stream cipher (RFC7539) + * The ChaCha stream cipher (RFC7539) * * Copyright (C) 2015 Martin Willi */ +#include <crypto/algapi.h> // for crypto_xor_cpy #include <crypto/chacha.h> -#include <linux/bitops.h> -#include <linux/bug.h> #include <linux/export.h> #include <linux/kernel.h> -#include <linux/string.h> -#include <linux/unaligned.h> +#include <linux/module.h> -static void chacha_permute(struct chacha_state *state, int nrounds) +static void __maybe_unused +chacha_crypt_generic(struct chacha_state *state, u8 *dst, const u8 *src, + unsigned int bytes, int nrounds) { - u32 *x = state->x; - int i; - - /* whitelist the allowed round counts */ - WARN_ON_ONCE(nrounds != 20 && nrounds != 12); - - for (i = 0; i < nrounds; i += 2) { - x[0] += x[4]; x[12] = rol32(x[12] ^ x[0], 16); - x[1] += x[5]; x[13] = rol32(x[13] ^ x[1], 16); - x[2] += x[6]; x[14] = rol32(x[14] ^ x[2], 16); - x[3] += x[7]; x[15] = rol32(x[15] ^ x[3], 16); - - x[8] += x[12]; x[4] = rol32(x[4] ^ x[8], 12); - x[9] += x[13]; x[5] = rol32(x[5] ^ x[9], 12); - x[10] += x[14]; x[6] = rol32(x[6] ^ x[10], 12); - x[11] += x[15]; x[7] = rol32(x[7] ^ x[11], 12); - - x[0] += x[4]; x[12] = rol32(x[12] ^ x[0], 8); - x[1] += x[5]; x[13] = rol32(x[13] ^ x[1], 8); - x[2] += x[6]; x[14] = rol32(x[14] ^ x[2], 8); - x[3] += x[7]; x[15] = rol32(x[15] ^ x[3], 8); - - x[8] += x[12]; x[4] = rol32(x[4] ^ x[8], 7); - x[9] += x[13]; x[5] = rol32(x[5] ^ x[9], 7); - x[10] += x[14]; x[6] = rol32(x[6] ^ x[10], 7); - x[11] += x[15]; x[7] = rol32(x[7] ^ x[11], 7); - - x[0] += x[5]; x[15] = rol32(x[15] ^ x[0], 16); - x[1] += x[6]; x[12] = rol32(x[12] ^ x[1], 16); - x[2] += x[7]; x[13] = rol32(x[13] ^ x[2], 16); - x[3] += x[4]; x[14] = rol32(x[14] ^ x[3], 16); - - x[10] += x[15]; x[5] = rol32(x[5] ^ x[10], 12); - x[11] += x[12]; x[6] = rol32(x[6] ^ x[11], 12); - x[8] += x[13]; x[7] = rol32(x[7] ^ x[8], 12); - x[9] += x[14]; x[4] = rol32(x[4] ^ x[9], 12); - - x[0] += x[5]; x[15] = rol32(x[15] ^ x[0], 8); - x[1] += x[6]; x[12] = rol32(x[12] ^ x[1], 8); - x[2] += x[7]; x[13] = rol32(x[13] ^ x[2], 8); - x[3] += x[4]; x[14] = rol32(x[14] ^ x[3], 8); - - x[10] += x[15]; x[5] = rol32(x[5] ^ x[10], 7); - x[11] += x[12]; x[6] = rol32(x[6] ^ x[11], 7); - x[8] += x[13]; x[7] = rol32(x[7] ^ x[8], 7); - x[9] += x[14]; x[4] = rol32(x[4] ^ x[9], 7); + /* aligned to potentially speed up crypto_xor() */ + u8 stream[CHACHA_BLOCK_SIZE] __aligned(sizeof(long)); + + while (bytes >= CHACHA_BLOCK_SIZE) { + chacha_block_generic(state, stream, nrounds); + crypto_xor_cpy(dst, src, stream, CHACHA_BLOCK_SIZE); + bytes -= CHACHA_BLOCK_SIZE; + dst += CHACHA_BLOCK_SIZE; + src += CHACHA_BLOCK_SIZE; + } + if (bytes) { + chacha_block_generic(state, stream, nrounds); + crypto_xor_cpy(dst, src, stream, bytes); } } -/** - * chacha_block_generic - generate one keystream block and increment block counter - * @state: input state matrix - * @out: output keystream block - * @nrounds: number of rounds (20 or 12; 20 is recommended) - * - * This is the ChaCha core, a function from 64-byte strings to 64-byte strings. - * The caller has already converted the endianness of the input. This function - * also handles incrementing the block counter in the input matrix. - */ -void chacha_block_generic(struct chacha_state *state, - u8 out[CHACHA_BLOCK_SIZE], int nrounds) -{ - struct chacha_state permuted_state = *state; - int i; - - chacha_permute(&permuted_state, nrounds); - - for (i = 0; i < ARRAY_SIZE(state->x); i++) - put_unaligned_le32(permuted_state.x[i] + state->x[i], - &out[i * sizeof(u32)]); +#ifdef CONFIG_CRYPTO_LIB_CHACHA_ARCH +#include "chacha.h" /* $(SRCARCH)/chacha.h */ +#else +#define chacha_crypt_arch chacha_crypt_generic +#define hchacha_block_arch hchacha_block_generic +#endif - state->x[12]++; +void chacha_crypt(struct chacha_state *state, u8 *dst, const u8 *src, + unsigned int bytes, int nrounds) +{ + chacha_crypt_arch(state, dst, src, bytes, nrounds); } -EXPORT_SYMBOL(chacha_block_generic); +EXPORT_SYMBOL_GPL(chacha_crypt); -/** - * hchacha_block_generic - abbreviated ChaCha core, for XChaCha - * @state: input state matrix - * @out: the output words - * @nrounds: number of rounds (20 or 12; 20 is recommended) - * - * HChaCha is the ChaCha equivalent of HSalsa and is an intermediate step - * towards XChaCha (see https://cr.yp.to/snuffle/xsalsa-20081128.pdf). HChaCha - * skips the final addition of the initial state, and outputs only certain words - * of the state. It should not be used for streaming directly. - */ -void hchacha_block_generic(const struct chacha_state *state, - u32 out[HCHACHA_OUT_WORDS], int nrounds) +void hchacha_block(const struct chacha_state *state, + u32 out[HCHACHA_OUT_WORDS], int nrounds) { - struct chacha_state permuted_state = *state; + hchacha_block_arch(state, out, nrounds); +} +EXPORT_SYMBOL_GPL(hchacha_block); - chacha_permute(&permuted_state, nrounds); +#ifdef chacha_mod_init_arch +static int __init chacha_mod_init(void) +{ + chacha_mod_init_arch(); + return 0; +} +subsys_initcall(chacha_mod_init); - memcpy(&out[0], &permuted_state.x[0], 16); - memcpy(&out[4], &permuted_state.x[12], 16); +static void __exit chacha_mod_exit(void) +{ } -EXPORT_SYMBOL(hchacha_block_generic); +module_exit(chacha_mod_exit); +#endif + +MODULE_DESCRIPTION("ChaCha stream cipher (RFC7539)"); +MODULE_LICENSE("GPL"); |