134 lines
3.3 KiB
C
134 lines
3.3 KiB
C
/*
|
|
* Cryptographic API.
|
|
*
|
|
* HMAC: Keyed-Hashing for Message Authentication (RFC2104).
|
|
*
|
|
* Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
|
|
*
|
|
* The HMAC implementation is derived from USAGI.
|
|
* Copyright (c) 2002 Kazunori Miyazawa <miyazawa@linux-ipv6.org> / USAGI
|
|
*
|
|
* 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 <linux/crypto.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/highmem.h>
|
|
#include <linux/slab.h>
|
|
#include <asm/scatterlist.h>
|
|
#include "internal.h"
|
|
|
|
static void hash_key(struct crypto_tfm *tfm, u8 *key, unsigned int keylen)
|
|
{
|
|
struct scatterlist tmp;
|
|
|
|
tmp.page = virt_to_page(key);
|
|
tmp.offset = offset_in_page(key);
|
|
tmp.length = keylen;
|
|
crypto_digest_digest(tfm, &tmp, 1, key);
|
|
|
|
}
|
|
|
|
int crypto_alloc_hmac_block(struct crypto_tfm *tfm)
|
|
{
|
|
int ret = 0;
|
|
|
|
BUG_ON(!crypto_tfm_alg_blocksize(tfm));
|
|
|
|
tfm->crt_digest.dit_hmac_block = kmalloc(crypto_tfm_alg_blocksize(tfm),
|
|
GFP_KERNEL);
|
|
if (tfm->crt_digest.dit_hmac_block == NULL)
|
|
ret = -ENOMEM;
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
void crypto_free_hmac_block(struct crypto_tfm *tfm)
|
|
{
|
|
kfree(tfm->crt_digest.dit_hmac_block);
|
|
}
|
|
|
|
void crypto_hmac_init(struct crypto_tfm *tfm, u8 *key, unsigned int *keylen)
|
|
{
|
|
unsigned int i;
|
|
struct scatterlist tmp;
|
|
char *ipad = tfm->crt_digest.dit_hmac_block;
|
|
|
|
if (*keylen > crypto_tfm_alg_blocksize(tfm)) {
|
|
hash_key(tfm, key, *keylen);
|
|
*keylen = crypto_tfm_alg_digestsize(tfm);
|
|
}
|
|
|
|
memset(ipad, 0, crypto_tfm_alg_blocksize(tfm));
|
|
memcpy(ipad, key, *keylen);
|
|
|
|
for (i = 0; i < crypto_tfm_alg_blocksize(tfm); i++)
|
|
ipad[i] ^= 0x36;
|
|
|
|
tmp.page = virt_to_page(ipad);
|
|
tmp.offset = offset_in_page(ipad);
|
|
tmp.length = crypto_tfm_alg_blocksize(tfm);
|
|
|
|
crypto_digest_init(tfm);
|
|
crypto_digest_update(tfm, &tmp, 1);
|
|
}
|
|
|
|
void crypto_hmac_update(struct crypto_tfm *tfm,
|
|
struct scatterlist *sg, unsigned int nsg)
|
|
{
|
|
crypto_digest_update(tfm, sg, nsg);
|
|
}
|
|
|
|
void crypto_hmac_final(struct crypto_tfm *tfm, u8 *key,
|
|
unsigned int *keylen, u8 *out)
|
|
{
|
|
unsigned int i;
|
|
struct scatterlist tmp;
|
|
char *opad = tfm->crt_digest.dit_hmac_block;
|
|
|
|
if (*keylen > crypto_tfm_alg_blocksize(tfm)) {
|
|
hash_key(tfm, key, *keylen);
|
|
*keylen = crypto_tfm_alg_digestsize(tfm);
|
|
}
|
|
|
|
crypto_digest_final(tfm, out);
|
|
|
|
memset(opad, 0, crypto_tfm_alg_blocksize(tfm));
|
|
memcpy(opad, key, *keylen);
|
|
|
|
for (i = 0; i < crypto_tfm_alg_blocksize(tfm); i++)
|
|
opad[i] ^= 0x5c;
|
|
|
|
tmp.page = virt_to_page(opad);
|
|
tmp.offset = offset_in_page(opad);
|
|
tmp.length = crypto_tfm_alg_blocksize(tfm);
|
|
|
|
crypto_digest_init(tfm);
|
|
crypto_digest_update(tfm, &tmp, 1);
|
|
|
|
tmp.page = virt_to_page(out);
|
|
tmp.offset = offset_in_page(out);
|
|
tmp.length = crypto_tfm_alg_digestsize(tfm);
|
|
|
|
crypto_digest_update(tfm, &tmp, 1);
|
|
crypto_digest_final(tfm, out);
|
|
}
|
|
|
|
void crypto_hmac(struct crypto_tfm *tfm, u8 *key, unsigned int *keylen,
|
|
struct scatterlist *sg, unsigned int nsg, u8 *out)
|
|
{
|
|
crypto_hmac_init(tfm, key, keylen);
|
|
crypto_hmac_update(tfm, sg, nsg);
|
|
crypto_hmac_final(tfm, key, keylen, out);
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(crypto_hmac_init);
|
|
EXPORT_SYMBOL_GPL(crypto_hmac_update);
|
|
EXPORT_SYMBOL_GPL(crypto_hmac_final);
|
|
EXPORT_SYMBOL_GPL(crypto_hmac);
|
|
|