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13cecc526d
Consolidate the ChaCha code into a single module (excluding chacha-block-generic.c which remains always built-in for random.c), similar to various other algorithms: - Each arch now provides a header file lib/crypto/$(SRCARCH)/chacha.h, replacing lib/crypto/$(SRCARCH)/chacha*.c. The header defines chacha_crypt_arch() and hchacha_block_arch(). It is included by lib/crypto/chacha.c, and thus the code gets built into the single libchacha module, with improved inlining in some cases. - Whether arch-optimized ChaCha is buildable is now controlled centrally by lib/crypto/Kconfig instead of by lib/crypto/$(SRCARCH)/Kconfig. The conditions for enabling it remain the same as before, and it remains enabled by default. - Any additional arch-specific translation units for the optimized ChaCha code, such as assembly files, are now compiled by lib/crypto/Makefile instead of lib/crypto/$(SRCARCH)/Makefile. This removes the last use for the Makefile and Kconfig files in the arm64, mips, powerpc, riscv, and s390 subdirectories of lib/crypto/. So also remove those files and the references to them. Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20250827151131.27733-7-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@kernel.org>
100 lines
2.8 KiB
C
100 lines
2.8 KiB
C
/*
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* ChaCha and HChaCha functions (ARM64 optimized)
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*
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* Copyright (C) 2016 - 2017 Linaro, Ltd. <ard.biesheuvel@linaro.org>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* Based on:
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* ChaCha20 256-bit cipher algorithm, RFC7539, SIMD glue code
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*
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* Copyright (C) 2015 Martin Willi
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*/
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#include <crypto/internal/simd.h>
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#include <linux/jump_label.h>
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#include <linux/kernel.h>
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#include <asm/hwcap.h>
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#include <asm/neon.h>
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#include <asm/simd.h>
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asmlinkage void chacha_block_xor_neon(const struct chacha_state *state,
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u8 *dst, const u8 *src, int nrounds);
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asmlinkage void chacha_4block_xor_neon(const struct chacha_state *state,
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u8 *dst, const u8 *src,
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int nrounds, int bytes);
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asmlinkage void hchacha_block_neon(const struct chacha_state *state,
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u32 out[HCHACHA_OUT_WORDS], int nrounds);
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static __ro_after_init DEFINE_STATIC_KEY_FALSE(have_neon);
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static void chacha_doneon(struct chacha_state *state, u8 *dst, const u8 *src,
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int bytes, int nrounds)
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{
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while (bytes > 0) {
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int l = min(bytes, CHACHA_BLOCK_SIZE * 5);
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if (l <= CHACHA_BLOCK_SIZE) {
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u8 buf[CHACHA_BLOCK_SIZE];
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memcpy(buf, src, l);
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chacha_block_xor_neon(state, buf, buf, nrounds);
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memcpy(dst, buf, l);
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state->x[12] += 1;
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break;
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}
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chacha_4block_xor_neon(state, dst, src, nrounds, l);
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bytes -= l;
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src += l;
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dst += l;
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state->x[12] += DIV_ROUND_UP(l, CHACHA_BLOCK_SIZE);
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}
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}
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static void hchacha_block_arch(const struct chacha_state *state,
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u32 out[HCHACHA_OUT_WORDS], int nrounds)
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{
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if (!static_branch_likely(&have_neon) || !crypto_simd_usable()) {
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hchacha_block_generic(state, out, nrounds);
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} else {
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kernel_neon_begin();
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hchacha_block_neon(state, out, nrounds);
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kernel_neon_end();
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}
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}
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static void chacha_crypt_arch(struct chacha_state *state, u8 *dst,
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const u8 *src, unsigned int bytes, int nrounds)
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{
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if (!static_branch_likely(&have_neon) || bytes <= CHACHA_BLOCK_SIZE ||
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!crypto_simd_usable())
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return chacha_crypt_generic(state, dst, src, bytes, nrounds);
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do {
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unsigned int todo = min_t(unsigned int, bytes, SZ_4K);
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kernel_neon_begin();
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chacha_doneon(state, dst, src, todo, nrounds);
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kernel_neon_end();
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bytes -= todo;
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src += todo;
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dst += todo;
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} while (bytes);
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}
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#define chacha_mod_init_arch chacha_mod_init_arch
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static void chacha_mod_init_arch(void)
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{
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if (cpu_have_named_feature(ASIMD))
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static_branch_enable(&have_neon);
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}
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