leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

crypto: salsa20 - export generic helpers

Browse Source 
Export the Salsa20 constants, transform context, and initialization
functions so that they can be reused by the x86 implementation.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Eric Biggers 2018-01-05 11:09:58 -08:00 committed by Herbert Xu
parent b62b3db76f
commit eb772f37ae
2 changed files with 34 additions and 13 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

20
crypto/salsa20_generic.c
View File

@ -21,17 +21,9 @@
#include <asm/unaligned.h>
#include <crypto/internal/skcipher.h>
#include <crypto/salsa20.h>
#include <linux/module.h>
#define SALSA20_IV_SIZE 8
#define SALSA20_MIN_KEY_SIZE 16
#define SALSA20_MAX_KEY_SIZE 32
#define SALSA20_BLOCK_SIZE 64
struct salsa20_ctx {
u32 initial_state[16];
};
static void salsa20_block(u32 *state, __le32 *stream)
{
u32 x[16];
@ -101,15 +93,16 @@ static void salsa20_docrypt(u32 *state, u8 *dst, const u8 *src,
}
}
static void salsa20_init(u32 *state, const struct salsa20_ctx *ctx,
void crypto_salsa20_init(u32 *state, const struct salsa20_ctx *ctx,
const u8 *iv)
{
memcpy(state, ctx->initial_state, sizeof(ctx->initial_state));
state[6] = get_unaligned_le32(iv + 0);
state[7] = get_unaligned_le32(iv + 4);
}
EXPORT_SYMBOL_GPL(crypto_salsa20_init);
static int salsa20_setkey(struct crypto_skcipher *tfm, const u8 *key,
int crypto_salsa20_setkey(struct crypto_skcipher *tfm, const u8 *key,
unsigned int keysize)
{
static const char sigma[16] = "expand 32-byte k";
@ -150,6 +143,7 @@ static int salsa20_setkey(struct crypto_skcipher *tfm, const u8 *key,
return 0;
}
EXPORT_SYMBOL_GPL(crypto_salsa20_setkey);
static int salsa20_crypt(struct skcipher_request *req)
{
@ -161,7 +155,7 @@ static int salsa20_crypt(struct skcipher_request *req)
err = skcipher_walk_virt(&walk, req, true);
salsa20_init(state, ctx, walk.iv);
crypto_salsa20_init(state, ctx, walk.iv);
while (walk.nbytes > 0) {
unsigned int nbytes = walk.nbytes;
@ -189,7 +183,7 @@ static struct skcipher_alg alg = {
.max_keysize = SALSA20_MAX_KEY_SIZE,
.ivsize = SALSA20_IV_SIZE,
.chunksize = SALSA20_BLOCK_SIZE,
.setkey = salsa20_setkey,
.setkey = crypto_salsa20_setkey,
.encrypt = salsa20_crypt,
.decrypt = salsa20_crypt,
};

27
include/crypto/salsa20.h Normal file
View File

@ -0,0 +1,27 @@
/* SPDX-License-Identifier: GPL-2.0 */
/*
* Common values for the Salsa20 algorithm
*/
#ifndef _CRYPTO_SALSA20_H
#define _CRYPTO_SALSA20_H
#include <linux/types.h>
#define SALSA20_IV_SIZE 8
#define SALSA20_MIN_KEY_SIZE 16
#define SALSA20_MAX_KEY_SIZE 32
#define SALSA20_BLOCK_SIZE 64
struct crypto_skcipher;
struct salsa20_ctx {
u32 initial_state[16];
};
void crypto_salsa20_init(u32 *state, const struct salsa20_ctx *ctx,
const u8 *iv);
int crypto_salsa20_setkey(struct crypto_skcipher *tfm, const u8 *key,
unsigned int keysize);
#endif /* _CRYPTO_SALSA20_H */