cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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libchacha.c (896B)

      1// SPDX-License-Identifier: GPL-2.0-or-later
      2/*
      3 * The ChaCha stream cipher (RFC7539)
      4 *
      5 * Copyright (C) 2015 Martin Willi
      6 */
      7
      8#include <linux/kernel.h>
      9#include <linux/export.h>
     10#include <linux/module.h>
     11
     12#include <crypto/algapi.h> // for crypto_xor_cpy
     13#include <crypto/chacha.h>
     14
     15void chacha_crypt_generic(u32 *state, u8 *dst, const u8 *src,
     16			  unsigned int bytes, int nrounds)
     17{
     18	/* aligned to potentially speed up crypto_xor() */
     19	u8 stream[CHACHA_BLOCK_SIZE] __aligned(sizeof(long));
     20
     21	while (bytes >= CHACHA_BLOCK_SIZE) {
     22		chacha_block_generic(state, stream, nrounds);
     23		crypto_xor_cpy(dst, src, stream, CHACHA_BLOCK_SIZE);
     24		bytes -= CHACHA_BLOCK_SIZE;
     25		dst += CHACHA_BLOCK_SIZE;
     26		src += CHACHA_BLOCK_SIZE;
     27	}
     28	if (bytes) {
     29		chacha_block_generic(state, stream, nrounds);
     30		crypto_xor_cpy(dst, src, stream, bytes);
     31	}
     32}
     33EXPORT_SYMBOL(chacha_crypt_generic);
     34
     35MODULE_LICENSE("GPL");