mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-23 17:30:02 +00:00
![Kees Cook](/assets/img/avatar_default.png)
This prefixes all crypto module loading with "crypto-" so we never run the risk of exposing module auto-loading to userspace via a crypto API, as demonstrated by Mathias Krause: https://lkml.org/lkml/2013/3/4/70 Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
187 lines
3.6 KiB
C
187 lines
3.6 KiB
C
/*
|
|
* Cryptographic API
|
|
*
|
|
* Michael MIC (IEEE 802.11i/TKIP) keyed digest
|
|
*
|
|
* Copyright (c) 2004 Jouni Malinen <j@w1.fi>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*/
|
|
#include <crypto/internal/hash.h>
|
|
#include <asm/byteorder.h>
|
|
#include <linux/init.h>
|
|
#include <linux/module.h>
|
|
#include <linux/string.h>
|
|
#include <linux/types.h>
|
|
|
|
|
|
struct michael_mic_ctx {
|
|
u32 l, r;
|
|
};
|
|
|
|
struct michael_mic_desc_ctx {
|
|
u8 pending[4];
|
|
size_t pending_len;
|
|
|
|
u32 l, r;
|
|
};
|
|
|
|
static inline u32 xswap(u32 val)
|
|
{
|
|
return ((val & 0x00ff00ff) << 8) | ((val & 0xff00ff00) >> 8);
|
|
}
|
|
|
|
|
|
#define michael_block(l, r) \
|
|
do { \
|
|
r ^= rol32(l, 17); \
|
|
l += r; \
|
|
r ^= xswap(l); \
|
|
l += r; \
|
|
r ^= rol32(l, 3); \
|
|
l += r; \
|
|
r ^= ror32(l, 2); \
|
|
l += r; \
|
|
} while (0)
|
|
|
|
|
|
static int michael_init(struct shash_desc *desc)
|
|
{
|
|
struct michael_mic_desc_ctx *mctx = shash_desc_ctx(desc);
|
|
struct michael_mic_ctx *ctx = crypto_shash_ctx(desc->tfm);
|
|
mctx->pending_len = 0;
|
|
mctx->l = ctx->l;
|
|
mctx->r = ctx->r;
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
static int michael_update(struct shash_desc *desc, const u8 *data,
|
|
unsigned int len)
|
|
{
|
|
struct michael_mic_desc_ctx *mctx = shash_desc_ctx(desc);
|
|
const __le32 *src;
|
|
|
|
if (mctx->pending_len) {
|
|
int flen = 4 - mctx->pending_len;
|
|
if (flen > len)
|
|
flen = len;
|
|
memcpy(&mctx->pending[mctx->pending_len], data, flen);
|
|
mctx->pending_len += flen;
|
|
data += flen;
|
|
len -= flen;
|
|
|
|
if (mctx->pending_len < 4)
|
|
return 0;
|
|
|
|
src = (const __le32 *)mctx->pending;
|
|
mctx->l ^= le32_to_cpup(src);
|
|
michael_block(mctx->l, mctx->r);
|
|
mctx->pending_len = 0;
|
|
}
|
|
|
|
src = (const __le32 *)data;
|
|
|
|
while (len >= 4) {
|
|
mctx->l ^= le32_to_cpup(src++);
|
|
michael_block(mctx->l, mctx->r);
|
|
len -= 4;
|
|
}
|
|
|
|
if (len > 0) {
|
|
mctx->pending_len = len;
|
|
memcpy(mctx->pending, src, len);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
static int michael_final(struct shash_desc *desc, u8 *out)
|
|
{
|
|
struct michael_mic_desc_ctx *mctx = shash_desc_ctx(desc);
|
|
u8 *data = mctx->pending;
|
|
__le32 *dst = (__le32 *)out;
|
|
|
|
/* Last block and padding (0x5a, 4..7 x 0) */
|
|
switch (mctx->pending_len) {
|
|
case 0:
|
|
mctx->l ^= 0x5a;
|
|
break;
|
|
case 1:
|
|
mctx->l ^= data[0] | 0x5a00;
|
|
break;
|
|
case 2:
|
|
mctx->l ^= data[0] | (data[1] << 8) | 0x5a0000;
|
|
break;
|
|
case 3:
|
|
mctx->l ^= data[0] | (data[1] << 8) | (data[2] << 16) |
|
|
0x5a000000;
|
|
break;
|
|
}
|
|
michael_block(mctx->l, mctx->r);
|
|
/* l ^= 0; */
|
|
michael_block(mctx->l, mctx->r);
|
|
|
|
dst[0] = cpu_to_le32(mctx->l);
|
|
dst[1] = cpu_to_le32(mctx->r);
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
static int michael_setkey(struct crypto_shash *tfm, const u8 *key,
|
|
unsigned int keylen)
|
|
{
|
|
struct michael_mic_ctx *mctx = crypto_shash_ctx(tfm);
|
|
|
|
const __le32 *data = (const __le32 *)key;
|
|
|
|
if (keylen != 8) {
|
|
crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
|
|
return -EINVAL;
|
|
}
|
|
|
|
mctx->l = le32_to_cpu(data[0]);
|
|
mctx->r = le32_to_cpu(data[1]);
|
|
return 0;
|
|
}
|
|
|
|
static struct shash_alg alg = {
|
|
.digestsize = 8,
|
|
.setkey = michael_setkey,
|
|
.init = michael_init,
|
|
.update = michael_update,
|
|
.final = michael_final,
|
|
.descsize = sizeof(struct michael_mic_desc_ctx),
|
|
.base = {
|
|
.cra_name = "michael_mic",
|
|
.cra_blocksize = 8,
|
|
.cra_alignmask = 3,
|
|
.cra_ctxsize = sizeof(struct michael_mic_ctx),
|
|
.cra_module = THIS_MODULE,
|
|
}
|
|
};
|
|
|
|
static int __init michael_mic_init(void)
|
|
{
|
|
return crypto_register_shash(&alg);
|
|
}
|
|
|
|
|
|
static void __exit michael_mic_exit(void)
|
|
{
|
|
crypto_unregister_shash(&alg);
|
|
}
|
|
|
|
|
|
module_init(michael_mic_init);
|
|
module_exit(michael_mic_exit);
|
|
|
|
MODULE_LICENSE("GPL v2");
|
|
MODULE_DESCRIPTION("Michael MIC");
|
|
MODULE_AUTHOR("Jouni Malinen <j@w1.fi>");
|
|
MODULE_ALIAS_CRYPTO("michael_mic");
|