mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-06 06:46:38 +07:00
9f480faec5
When chacha20_block() outputs the keystream block, it uses 'u32' stores directly. However, the callers (crypto/chacha20_generic.c and drivers/char/random.c) declare the keystream buffer as a 'u8' array, which is not guaranteed to have the needed alignment. Fix it by having both callers declare the keystream as a 'u32' array. For now this is preferable to switching over to the unaligned access macros because chacha20_block() is only being used in cases where we can easily control the alignment (stack buffers). Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
137 lines
3.5 KiB
C
137 lines
3.5 KiB
C
/*
|
|
* ChaCha20 256-bit cipher algorithm, RFC7539
|
|
*
|
|
* Copyright (C) 2015 Martin Willi
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*/
|
|
|
|
#include <asm/unaligned.h>
|
|
#include <crypto/algapi.h>
|
|
#include <crypto/chacha20.h>
|
|
#include <crypto/internal/skcipher.h>
|
|
#include <linux/module.h>
|
|
|
|
static void chacha20_docrypt(u32 *state, u8 *dst, const u8 *src,
|
|
unsigned int bytes)
|
|
{
|
|
u32 stream[CHACHA20_BLOCK_WORDS];
|
|
|
|
if (dst != src)
|
|
memcpy(dst, src, bytes);
|
|
|
|
while (bytes >= CHACHA20_BLOCK_SIZE) {
|
|
chacha20_block(state, stream);
|
|
crypto_xor(dst, (const u8 *)stream, CHACHA20_BLOCK_SIZE);
|
|
bytes -= CHACHA20_BLOCK_SIZE;
|
|
dst += CHACHA20_BLOCK_SIZE;
|
|
}
|
|
if (bytes) {
|
|
chacha20_block(state, stream);
|
|
crypto_xor(dst, (const u8 *)stream, bytes);
|
|
}
|
|
}
|
|
|
|
void crypto_chacha20_init(u32 *state, struct chacha20_ctx *ctx, u8 *iv)
|
|
{
|
|
state[0] = 0x61707865; /* "expa" */
|
|
state[1] = 0x3320646e; /* "nd 3" */
|
|
state[2] = 0x79622d32; /* "2-by" */
|
|
state[3] = 0x6b206574; /* "te k" */
|
|
state[4] = ctx->key[0];
|
|
state[5] = ctx->key[1];
|
|
state[6] = ctx->key[2];
|
|
state[7] = ctx->key[3];
|
|
state[8] = ctx->key[4];
|
|
state[9] = ctx->key[5];
|
|
state[10] = ctx->key[6];
|
|
state[11] = ctx->key[7];
|
|
state[12] = get_unaligned_le32(iv + 0);
|
|
state[13] = get_unaligned_le32(iv + 4);
|
|
state[14] = get_unaligned_le32(iv + 8);
|
|
state[15] = get_unaligned_le32(iv + 12);
|
|
}
|
|
EXPORT_SYMBOL_GPL(crypto_chacha20_init);
|
|
|
|
int crypto_chacha20_setkey(struct crypto_skcipher *tfm, const u8 *key,
|
|
unsigned int keysize)
|
|
{
|
|
struct chacha20_ctx *ctx = crypto_skcipher_ctx(tfm);
|
|
int i;
|
|
|
|
if (keysize != CHACHA20_KEY_SIZE)
|
|
return -EINVAL;
|
|
|
|
for (i = 0; i < ARRAY_SIZE(ctx->key); i++)
|
|
ctx->key[i] = get_unaligned_le32(key + i * sizeof(u32));
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(crypto_chacha20_setkey);
|
|
|
|
int crypto_chacha20_crypt(struct skcipher_request *req)
|
|
{
|
|
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
|
|
struct chacha20_ctx *ctx = crypto_skcipher_ctx(tfm);
|
|
struct skcipher_walk walk;
|
|
u32 state[16];
|
|
int err;
|
|
|
|
err = skcipher_walk_virt(&walk, req, true);
|
|
|
|
crypto_chacha20_init(state, ctx, walk.iv);
|
|
|
|
while (walk.nbytes > 0) {
|
|
unsigned int nbytes = walk.nbytes;
|
|
|
|
if (nbytes < walk.total)
|
|
nbytes = round_down(nbytes, walk.stride);
|
|
|
|
chacha20_docrypt(state, walk.dst.virt.addr, walk.src.virt.addr,
|
|
nbytes);
|
|
err = skcipher_walk_done(&walk, walk.nbytes - nbytes);
|
|
}
|
|
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL_GPL(crypto_chacha20_crypt);
|
|
|
|
static struct skcipher_alg alg = {
|
|
.base.cra_name = "chacha20",
|
|
.base.cra_driver_name = "chacha20-generic",
|
|
.base.cra_priority = 100,
|
|
.base.cra_blocksize = 1,
|
|
.base.cra_ctxsize = sizeof(struct chacha20_ctx),
|
|
.base.cra_module = THIS_MODULE,
|
|
|
|
.min_keysize = CHACHA20_KEY_SIZE,
|
|
.max_keysize = CHACHA20_KEY_SIZE,
|
|
.ivsize = CHACHA20_IV_SIZE,
|
|
.chunksize = CHACHA20_BLOCK_SIZE,
|
|
.setkey = crypto_chacha20_setkey,
|
|
.encrypt = crypto_chacha20_crypt,
|
|
.decrypt = crypto_chacha20_crypt,
|
|
};
|
|
|
|
static int __init chacha20_generic_mod_init(void)
|
|
{
|
|
return crypto_register_skcipher(&alg);
|
|
}
|
|
|
|
static void __exit chacha20_generic_mod_fini(void)
|
|
{
|
|
crypto_unregister_skcipher(&alg);
|
|
}
|
|
|
|
module_init(chacha20_generic_mod_init);
|
|
module_exit(chacha20_generic_mod_fini);
|
|
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_AUTHOR("Martin Willi <martin@strongswan.org>");
|
|
MODULE_DESCRIPTION("chacha20 cipher algorithm");
|
|
MODULE_ALIAS_CRYPTO("chacha20");
|
|
MODULE_ALIAS_CRYPTO("chacha20-generic");
|