// SPDX-License-Identifier: GPL-2.0-or-later
|
/*
|
* The ChaCha stream cipher (RFC7539)
|
*
|
* Copyright (C) 2015 Martin Willi
|
*/
|
|
#include <linux/kernel.h>
|
#include <linux/export.h>
|
#include <linux/module.h>
|
|
#include <crypto/algapi.h> // for crypto_xor_cpy
|
#include <crypto/chacha.h>
|
|
void chacha_crypt_generic(u32 *state, u8 *dst, const u8 *src,
|
unsigned int bytes, int nrounds)
|
{
|
/* 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);
|
}
|
}
|
EXPORT_SYMBOL(chacha_crypt_generic);
|
|
MODULE_LICENSE("GPL");
|
