redonkable/alistair23-linux
redonkable/alistair23-linux
1
0
Fork 0
Code Releases Activity
alistair23-linux/crypto/xcbc.c
Herbert Xu ebc610e5bc [CRYPTO] templates: Pass type/mask when creating instances 
This patch passes the type/mask along when constructing instances of
templates.  This is in preparation for templates that may support
multiple types of instances depending on what is requested.  For example,
the planned software async crypto driver will use this construct.

For the moment this allows us to check whether the instance constructed
is of the correct type and avoid returning success if the type does not
match.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2007-05-02 14:38:31 +10:00

371 lines
9.1 KiB
C
Raw Blame History

/*
* Copyright (C)2006 USAGI/WIDE Project
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* Author:
* Kazunori Miyazawa <miyazawa@linux-ipv6.org>
*/
#include <linux/crypto.h>
#include <linux/err.h>
#include <linux/hardirq.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/rtnetlink.h>
#include <linux/slab.h>
#include <linux/scatterlist.h>
#include "internal.h"
static u_int32_t ks[12] = {0x01010101, 0x01010101, 0x01010101, 0x01010101,
0x02020202, 0x02020202, 0x02020202, 0x02020202,
0x03030303, 0x03030303, 0x03030303, 0x03030303};
/*
* +------------------------
* | <parent tfm>
* +------------------------
* | crypto_xcbc_ctx
* +------------------------
* | odds (block size)
* +------------------------
* | prev (block size)
* +------------------------
* | key (block size)
* +------------------------
* | consts (block size * 3)
* +------------------------
*/
struct crypto_xcbc_ctx {
struct crypto_cipher *child;
u8 *odds;
u8 *prev;
u8 *key;
u8 *consts;
void (*xor)(u8 *a, const u8 *b, unsigned int bs);
unsigned int keylen;
unsigned int len;
};
static void xor_128(u8 *a, const u8 *b, unsigned int bs)
{
((u32 *)a)[0] ^= ((u32 *)b)[0];
((u32 *)a)[1] ^= ((u32 *)b)[1];
((u32 *)a)[2] ^= ((u32 *)b)[2];
((u32 *)a)[3] ^= ((u32 *)b)[3];
}
static int _crypto_xcbc_digest_setkey(struct crypto_hash *parent,
struct crypto_xcbc_ctx *ctx)
{
int bs = crypto_hash_blocksize(parent);
int err = 0;
u8 key1[bs];
if ((err = crypto_cipher_setkey(ctx->child, ctx->key, ctx->keylen)))
return err;
crypto_cipher_encrypt_one(ctx->child, key1, ctx->consts);
return crypto_cipher_setkey(ctx->child, key1, bs);
}
static int crypto_xcbc_digest_setkey(struct crypto_hash *parent,
const u8 *inkey, unsigned int keylen)
{
struct crypto_xcbc_ctx *ctx = crypto_hash_ctx_aligned(parent);
if (keylen != crypto_cipher_blocksize(ctx->child))
return -EINVAL;
ctx->keylen = keylen;
memcpy(ctx->key, inkey, keylen);
ctx->consts = (u8*)ks;
return _crypto_xcbc_digest_setkey(parent, ctx);
}
static int crypto_xcbc_digest_init(struct hash_desc *pdesc)
{
struct crypto_xcbc_ctx *ctx = crypto_hash_ctx_aligned(pdesc->tfm);
int bs = crypto_hash_blocksize(pdesc->tfm);
ctx->len = 0;
memset(ctx->odds, 0, bs);
memset(ctx->prev, 0, bs);
return 0;
}
static int crypto_xcbc_digest_update2(struct hash_desc *pdesc,
struct scatterlist *sg,
unsigned int nbytes)
{
struct crypto_hash *parent = pdesc->tfm;
struct crypto_xcbc_ctx *ctx = crypto_hash_ctx_aligned(parent);
struct crypto_cipher *tfm = ctx->child;
int bs = crypto_hash_blocksize(parent);
unsigned int i = 0;
do {
struct page *pg = sg[i].page;
unsigned int offset = sg[i].offset;
unsigned int slen = sg[i].length;
while (slen > 0) {
unsigned int len = min(slen, ((unsigned int)(PAGE_SIZE)) - offset);
char *p = crypto_kmap(pg, 0) + offset;
/* checking the data can fill the block */
if ((ctx->len + len) <= bs) {
memcpy(ctx->odds + ctx->len, p, len);
ctx->len += len;
slen -= len;
/* checking the rest of the page */
if (len + offset >= PAGE_SIZE) {
offset = 0;
pg++;
} else
offset += len;
crypto_kunmap(p, 0);
crypto_yield(pdesc->flags);
continue;
}
/* filling odds with new data and encrypting it */
memcpy(ctx->odds + ctx->len, p, bs - ctx->len);
len -= bs - ctx->len;
p += bs - ctx->len;
ctx->xor(ctx->prev, ctx->odds, bs);
crypto_cipher_encrypt_one(tfm, ctx->prev, ctx->prev);
/* clearing the length */
ctx->len = 0;
/* encrypting the rest of data */
while (len > bs) {
ctx->xor(ctx->prev, p, bs);
crypto_cipher_encrypt_one(tfm, ctx->prev,
ctx->prev);
p += bs;
len -= bs;
}
/* keeping the surplus of blocksize */
if (len) {
memcpy(ctx->odds, p, len);
ctx->len = len;
}
crypto_kunmap(p, 0);
crypto_yield(pdesc->flags);
slen -= min(slen, ((unsigned int)(PAGE_SIZE)) - offset);
offset = 0;
pg++;
}
nbytes-=sg[i].length;
i++;
} while (nbytes>0);
return 0;
}
static int crypto_xcbc_digest_update(struct hash_desc *pdesc,
struct scatterlist *sg,
unsigned int nbytes)
{
if (WARN_ON_ONCE(in_irq()))
return -EDEADLK;
return crypto_xcbc_digest_update2(pdesc, sg, nbytes);
}
static int crypto_xcbc_digest_final(struct hash_desc *pdesc, u8 *out)
{
struct crypto_hash *parent = pdesc->tfm;
struct crypto_xcbc_ctx *ctx = crypto_hash_ctx_aligned(parent);
struct crypto_cipher *tfm = ctx->child;
int bs = crypto_hash_blocksize(parent);
int err = 0;
if (ctx->len == bs) {
u8 key2[bs];
if ((err = crypto_cipher_setkey(tfm, ctx->key, ctx->keylen)) != 0)
return err;
crypto_cipher_encrypt_one(tfm, key2,
(u8 *)(ctx->consts + bs));
ctx->xor(ctx->prev, ctx->odds, bs);
ctx->xor(ctx->prev, key2, bs);
_crypto_xcbc_digest_setkey(parent, ctx);
crypto_cipher_encrypt_one(tfm, out, ctx->prev);
} else {
u8 key3[bs];
unsigned int rlen;
u8 *p = ctx->odds + ctx->len;
*p = 0x80;
p++;
rlen = bs - ctx->len -1;
if (rlen)
memset(p, 0, rlen);
if ((err = crypto_cipher_setkey(tfm, ctx->key, ctx->keylen)) != 0)
return err;
crypto_cipher_encrypt_one(tfm, key3,
(u8 *)(ctx->consts + bs * 2));
ctx->xor(ctx->prev, ctx->odds, bs);
ctx->xor(ctx->prev, key3, bs);
_crypto_xcbc_digest_setkey(parent, ctx);
crypto_cipher_encrypt_one(tfm, out, ctx->prev);
}
return 0;
}
static int crypto_xcbc_digest(struct hash_desc *pdesc,
struct scatterlist *sg, unsigned int nbytes, u8 *out)
{
if (WARN_ON_ONCE(in_irq()))
return -EDEADLK;
crypto_xcbc_digest_init(pdesc);
crypto_xcbc_digest_update2(pdesc, sg, nbytes);
return crypto_xcbc_digest_final(pdesc, out);
}
static int xcbc_init_tfm(struct crypto_tfm *tfm)
{
struct crypto_cipher *cipher;
struct crypto_instance *inst = (void *)tfm->__crt_alg;
struct crypto_spawn *spawn = crypto_instance_ctx(inst);
struct crypto_xcbc_ctx *ctx = crypto_hash_ctx_aligned(__crypto_hash_cast(tfm));
int bs = crypto_hash_blocksize(__crypto_hash_cast(tfm));
cipher = crypto_spawn_cipher(spawn);
if (IS_ERR(cipher))
return PTR_ERR(cipher);
switch(bs) {
case 16:
ctx->xor = xor_128;
break;
default:
return -EINVAL;
}
ctx->child = cipher;
ctx->odds = (u8*)(ctx+1);
ctx->prev = ctx->odds + bs;
ctx->key = ctx->prev + bs;
return 0;
};
static void xcbc_exit_tfm(struct crypto_tfm *tfm)
{
struct crypto_xcbc_ctx *ctx = crypto_hash_ctx_aligned(__crypto_hash_cast(tfm));
crypto_free_cipher(ctx->child);
}
static struct crypto_instance *xcbc_alloc(struct rtattr **tb)
{
struct crypto_instance *inst;
struct crypto_alg *alg;
int err;
err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_HASH);
if (err)
return ERR_PTR(err);
alg = crypto_get_attr_alg(tb, CRYPTO_ALG_TYPE_CIPHER,
CRYPTO_ALG_TYPE_MASK);
if (IS_ERR(alg))
return ERR_PTR(PTR_ERR(alg));
switch(alg->cra_blocksize) {
case 16:
break;
default:
return ERR_PTR(PTR_ERR(alg));
}
inst = crypto_alloc_instance("xcbc", alg);
if (IS_ERR(inst))
goto out_put_alg;
inst->alg.cra_flags = CRYPTO_ALG_TYPE_HASH;
inst->alg.cra_priority = alg->cra_priority;
inst->alg.cra_blocksize = alg->cra_blocksize;
inst->alg.cra_alignmask = alg->cra_alignmask;
inst->alg.cra_type = &crypto_hash_type;
inst->alg.cra_hash.digestsize =
(alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
CRYPTO_ALG_TYPE_HASH ? alg->cra_hash.digestsize :
alg->cra_blocksize;
inst->alg.cra_ctxsize = sizeof(struct crypto_xcbc_ctx) +
ALIGN(inst->alg.cra_blocksize * 3, sizeof(void *));
inst->alg.cra_init = xcbc_init_tfm;
inst->alg.cra_exit = xcbc_exit_tfm;
inst->alg.cra_hash.init = crypto_xcbc_digest_init;
inst->alg.cra_hash.update = crypto_xcbc_digest_update;
inst->alg.cra_hash.final = crypto_xcbc_digest_final;
inst->alg.cra_hash.digest = crypto_xcbc_digest;
inst->alg.cra_hash.setkey = crypto_xcbc_digest_setkey;
out_put_alg:
crypto_mod_put(alg);
return inst;
}
static void xcbc_free(struct crypto_instance *inst)
{
crypto_drop_spawn(crypto_instance_ctx(inst));
kfree(inst);
}
static struct crypto_template crypto_xcbc_tmpl = {
.name = "xcbc",
.alloc = xcbc_alloc,
.free = xcbc_free,
.module = THIS_MODULE,
};
static int __init crypto_xcbc_module_init(void)
{
return crypto_register_template(&crypto_xcbc_tmpl);
}
static void __exit crypto_xcbc_module_exit(void)
{
crypto_unregister_template(&crypto_xcbc_tmpl);
}
module_init(crypto_xcbc_module_init);
module_exit(crypto_xcbc_module_exit);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("XCBC keyed hash algorithm");
View git blame Copy permalink