Commit a71215f9 authored by Dmitry Eremin-Solenikov's avatar Dmitry Eremin-Solenikov Committed by Niels Möller

cmac: add 64-bit mode CMAC

Signed-off-by: default avatarDmitry Eremin-Solenikov <dbaryshkov@gmail.com>
parent c78f2fdb
......@@ -102,7 +102,7 @@ nettle_SOURCES = aes-decrypt-internal.c aes-decrypt.c \
gcm-aes256.c gcm-aes256-meta.c \
gcm-camellia128.c gcm-camellia128-meta.c \
gcm-camellia256.c gcm-camellia256-meta.c \
cmac.c cmac-aes128.c cmac-aes256.c \
cmac.c cmac64.c cmac-aes128.c cmac-aes256.c \
gosthash94.c gosthash94-meta.c \
hmac.c hmac-md5.c hmac-ripemd160.c hmac-sha1.c \
hmac-sha224.c hmac-sha256.c hmac-sha384.c hmac-sha512.c \
......
......@@ -44,6 +44,7 @@ extern "C" {
#endif
#define CMAC128_DIGEST_SIZE 16
#define CMAC64_DIGEST_SIZE 8
#define cmac128_set_key nettle_cmac128_set_key
#define cmac128_init nettle_cmac128_init
......@@ -56,6 +57,11 @@ extern "C" {
#define cmac_aes256_update nettle_cmac_aes256_update
#define cmac_aes256_digest nettle_cmac_aes256_digest
#define cmac64_set_key nettle_cmac64_set_key
#define cmac64_init nettle_cmac64_init
#define cmac64_update nettle_cmac64_update
#define cmac64_digest nettle_cmac64_digest
struct cmac128_key
{
union nettle_block16 K1;
......@@ -72,6 +78,22 @@ struct cmac128_ctx
size_t index;
};
struct cmac64_key
{
union nettle_block8 K1;
union nettle_block8 K2;
};
struct cmac64_ctx
{
/* MAC state */
union nettle_block8 X;
/* Block buffer */
union nettle_block8 block;
size_t index;
};
void
cmac128_set_key(struct cmac128_key *key, const void *cipher,
nettle_cipher_func *encrypt);
......@@ -118,6 +140,53 @@ cmac128_digest(struct cmac128_ctx *ctx, const struct cmac128_key *key,
(nettle_cipher_func *) (encrypt), \
(length), (digest)))
void
cmac64_set_key(struct cmac64_key *key, const void *cipher,
nettle_cipher_func *encrypt);
void
cmac64_init(struct cmac64_ctx *ctx);
void
cmac64_update(struct cmac64_ctx *ctx, const void *cipher,
nettle_cipher_func *encrypt,
size_t msg_len, const uint8_t *msg);
void
cmac64_digest(struct cmac64_ctx *ctx, const struct cmac64_key *key,
const void *cipher, nettle_cipher_func *encrypt,
unsigned length, uint8_t *digest);
#define CMAC64_CTX(type) \
{ struct cmac64_key key; struct cmac64_ctx ctx; type cipher; }
/* NOTE: Avoid using NULL, as we don't include anything defining it. */
#define CMAC64_SET_KEY(self, set_key, encrypt, cmac_key) \
do { \
(set_key)(&(self)->cipher, (cmac_key)); \
if (0) (encrypt)(&(self)->cipher, ~(size_t) 0, \
(uint8_t *) 0, (const uint8_t *) 0); \
cmac64_set_key(&(self)->key, &(self)->cipher, \
(nettle_cipher_func *) (encrypt)); \
cmac64_init(&(self)->ctx); \
} while (0)
#define CMAC64_UPDATE(self, encrypt, length, src) \
(0 ? (encrypt)(&(self)->cipher, ~(size_t) 0, \
(uint8_t *) 0, (const uint8_t *) 0) \
: cmac64_update(&(self)->ctx, &(self)->cipher, \
(nettle_cipher_func *)encrypt, \
(length), (src)))
#define CMAC64_DIGEST(self, encrypt, length, digest) \
(0 ? (encrypt)(&(self)->cipher, ~(size_t) 0, \
(uint8_t *) 0, (const uint8_t *) 0) \
: cmac64_digest(&(self)->ctx, &(self)->key, \
&(self)->cipher, \
(nettle_cipher_func *) (encrypt), \
(length), (digest)))
struct cmac_aes128_ctx CMAC128_CTX(struct aes128_ctx);
void
......
/*
AES-CMAC-128 (rfc 4493) / CMAC-64
Copyright (C) Stefan Metzmacher 2012
Copyright (C) Jeremy Allison 2012
Copyright (C) Michael Adam 2012
Copyright (C) 2017, Red Hat Inc.
Copyright (C) 2019, Dmitry Eremin-Solenikov
This file is part of GNU Nettle.
GNU Nettle is free software: you can redistribute it and/or
modify it under the terms of either:
* the GNU Lesser General Public License as published by the Free
Software Foundation; either version 3 of the License, or (at your
option) any later version.
or
* 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.
or both in parallel, as here.
GNU Nettle 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 copies of the GNU General Public License and
the GNU Lesser General Public License along with this program. If
not, see http://www.gnu.org/licenses/.
*/
#if HAVE_CONFIG_H
# include "config.h"
#endif
#include <assert.h>
#include <stdlib.h>
#include <string.h>
#include "cmac.h"
#include "memxor.h"
#include "nettle-internal.h"
#include "macros.h"
/* shift one and XOR with 0x87. */
#if WORDS_BIGENDIAN
static void
_cmac64_block_mulx(union nettle_block8 *dst,
const union nettle_block8 *src)
{
uint64_t carry = src->u64 >> 63;
dst->u64 = (src->u64 << 1) ^ (0x1b & -carry);
}
#else /* !WORDS_BIGENDIAN */
#define LE_SHIFT(x) ((((x) & 0x7f7f7f7f7f7f7f7f) << 1) | \
(((x) & 0x8080808080808080) >> 15))
static void
_cmac64_block_mulx(union nettle_block8 *dst,
const union nettle_block8 *src)
{
uint64_t carry = (src->u64 & 0x80) >> 7;
dst->u64 = LE_SHIFT(src->u64) ^ (0x1b00000000000000 & -carry);
}
#endif /* !WORDS_BIGENDIAN */
void
cmac64_set_key(struct cmac64_key *key, const void *cipher,
nettle_cipher_func *encrypt)
{
static const union nettle_block8 zero_block;
union nettle_block8 L;
/* step 1 - generate subkeys k1 and k2 */
encrypt(cipher, 8, L.b, zero_block.b);
_cmac64_block_mulx(&key->K1, &L);
_cmac64_block_mulx(&key->K2, &key->K1);
}
void
cmac64_init(struct cmac64_ctx *ctx)
{
memset(&ctx->X, 0, sizeof(ctx->X));
ctx->index = 0;
}
#define MIN(x,y) ((x)<(y)?(x):(y))
void
cmac64_update(struct cmac64_ctx *ctx, const void *cipher,
nettle_cipher_func *encrypt,
size_t msg_len, const uint8_t *msg)
{
union nettle_block16 Y;
/*
* check if we expand the block
*/
if (ctx->index < 8)
{
size_t len = MIN(8 - ctx->index, msg_len);
memcpy(&ctx->block.b[ctx->index], msg, len);
msg += len;
msg_len -= len;
ctx->index += len;
}
if (msg_len == 0) {
/* if it is still the last block, we are done */
return;
}
/*
* now checksum everything but the last block
*/
memxor3(Y.b, ctx->X.b, ctx->block.b, 8);
encrypt(cipher, 8, ctx->X.b, Y.b);
while (msg_len > 8)
{
memxor3(Y.b, ctx->X.b, msg, 8);
encrypt(cipher, 8, ctx->X.b, Y.b);
msg += 8;
msg_len -= 8;
}
/*
* copy the last block, it will be processed in
* cmac64_digest().
*/
memcpy(ctx->block.b, msg, msg_len);
ctx->index = msg_len;
}
void
cmac64_digest(struct cmac64_ctx *ctx, const struct cmac64_key *key,
const void *cipher, nettle_cipher_func *encrypt,
unsigned length, uint8_t *dst)
{
union nettle_block8 Y;
memset(ctx->block.b+ctx->index, 0, sizeof(ctx->block.b)-ctx->index);
/* re-use ctx->block for memxor output */
if (ctx->index < 8)
{
ctx->block.b[ctx->index] = 0x80;
memxor(ctx->block.b, key->K2.b, 8);
}
else
{
memxor(ctx->block.b, key->K1.b, 8);
}
memxor3(Y.b, ctx->block.b, ctx->X.b, 8);
assert(length <= 8);
if (length == 8)
{
encrypt(cipher, 8, dst, Y.b);
}
else
{
encrypt(cipher, 8, ctx->block.b, Y.b);
memcpy(dst, ctx->block.b, length);
}
/* reset state for re-use */
memset(&ctx->X, 0, sizeof(ctx->X));
ctx->index = 0;
}
......@@ -65,6 +65,12 @@ union nettle_block16
uint64_t u64[2];
};
union nettle_block8
{
uint8_t b[8];
uint64_t u64;
};
/* Randomness. Used by key generation and dsa signature creation. */
typedef void nettle_random_func(void *ctx,
size_t length, uint8_t *dst);
......
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment