mirror of https://gerrit.osmocom.org/libosmocore
125 lines
2.7 KiB
C
125 lines
2.7 KiB
C
/*! \file aes-internal-enc.c
|
|
* AES (Rijndael) cipher - encrypt.
|
|
*
|
|
* Modifications to public domain implementation:
|
|
* - support only 128-bit keys
|
|
* - cleanup
|
|
* - use C pre-processor to make it easier to change S table access
|
|
* - added option (AES_SMALL_TABLES) for reducing code size by about 8 kB at
|
|
* cost of reduced throughput (quite small difference on Pentium 4,
|
|
* 10-25% when using -O1 or -O2 optimization)
|
|
*/
|
|
/*
|
|
* Copyright (c) 2003-2005, 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.
|
|
*
|
|
* Alternatively, this software may be distributed under the terms of BSD
|
|
* license.
|
|
*
|
|
* SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
|
|
*
|
|
* See README and COPYING for more details.
|
|
*/
|
|
|
|
#include "includes.h"
|
|
|
|
#include "common.h"
|
|
#include "crypto.h"
|
|
#include "aes_i.h"
|
|
|
|
static void rijndaelEncrypt(const u32 rk[/*44*/], const u8 pt[16], u8 ct[16])
|
|
{
|
|
u32 s0, s1, s2, s3, t0, t1, t2, t3;
|
|
const int Nr = 10;
|
|
#ifndef FULL_UNROLL
|
|
int r;
|
|
#endif /* ?FULL_UNROLL */
|
|
|
|
/*
|
|
* map byte array block to cipher state
|
|
* and add initial round key:
|
|
*/
|
|
s0 = GETU32(pt ) ^ rk[0];
|
|
s1 = GETU32(pt + 4) ^ rk[1];
|
|
s2 = GETU32(pt + 8) ^ rk[2];
|
|
s3 = GETU32(pt + 12) ^ rk[3];
|
|
|
|
#define ROUND(i,d,s) \
|
|
d##0 = TE0(s##0) ^ TE1(s##1) ^ TE2(s##2) ^ TE3(s##3) ^ rk[4 * i]; \
|
|
d##1 = TE0(s##1) ^ TE1(s##2) ^ TE2(s##3) ^ TE3(s##0) ^ rk[4 * i + 1]; \
|
|
d##2 = TE0(s##2) ^ TE1(s##3) ^ TE2(s##0) ^ TE3(s##1) ^ rk[4 * i + 2]; \
|
|
d##3 = TE0(s##3) ^ TE1(s##0) ^ TE2(s##1) ^ TE3(s##2) ^ rk[4 * i + 3]
|
|
|
|
#ifdef FULL_UNROLL
|
|
|
|
ROUND(1,t,s);
|
|
ROUND(2,s,t);
|
|
ROUND(3,t,s);
|
|
ROUND(4,s,t);
|
|
ROUND(5,t,s);
|
|
ROUND(6,s,t);
|
|
ROUND(7,t,s);
|
|
ROUND(8,s,t);
|
|
ROUND(9,t,s);
|
|
|
|
rk += Nr << 2;
|
|
|
|
#else /* !FULL_UNROLL */
|
|
|
|
/* Nr - 1 full rounds: */
|
|
r = Nr >> 1;
|
|
for (;;) {
|
|
ROUND(1,t,s);
|
|
rk += 8;
|
|
if (--r == 0)
|
|
break;
|
|
ROUND(0,s,t);
|
|
}
|
|
|
|
#endif /* ?FULL_UNROLL */
|
|
|
|
#undef ROUND
|
|
|
|
/*
|
|
* apply last round and
|
|
* map cipher state to byte array block:
|
|
*/
|
|
s0 = TE41(t0) ^ TE42(t1) ^ TE43(t2) ^ TE44(t3) ^ rk[0];
|
|
PUTU32(ct , s0);
|
|
s1 = TE41(t1) ^ TE42(t2) ^ TE43(t3) ^ TE44(t0) ^ rk[1];
|
|
PUTU32(ct + 4, s1);
|
|
s2 = TE41(t2) ^ TE42(t3) ^ TE43(t0) ^ TE44(t1) ^ rk[2];
|
|
PUTU32(ct + 8, s2);
|
|
s3 = TE41(t3) ^ TE42(t0) ^ TE43(t1) ^ TE44(t2) ^ rk[3];
|
|
PUTU32(ct + 12, s3);
|
|
}
|
|
|
|
|
|
void * aes_encrypt_init(const u8 *key, size_t len)
|
|
{
|
|
u32 *rk;
|
|
if (len != 16)
|
|
return NULL;
|
|
rk = os_malloc(AES_PRIV_SIZE);
|
|
if (rk == NULL)
|
|
return NULL;
|
|
rijndaelKeySetupEnc(rk, key);
|
|
return rk;
|
|
}
|
|
|
|
|
|
void aes_encrypt(void *ctx, const u8 *plain, u8 *crypt)
|
|
{
|
|
rijndaelEncrypt(ctx, plain, crypt);
|
|
}
|
|
|
|
|
|
void aes_encrypt_deinit(void *ctx)
|
|
{
|
|
os_memset(ctx, 0, AES_PRIV_SIZE);
|
|
os_free(ctx);
|
|
}
|