| 8c14f7a5 | /* * A 32-bit implementation of the XTEA algorithm * Copyright (c) 2012 Samuel Pitoiset * * loosely based on the implementation of David Wheeler and Roger Needham * |
| 039e9fe0 | * This file is part of FFmpeg. |
| 8c14f7a5 | * |
| 039e9fe0 | * FFmpeg is free software; you can redistribute it and/or |
| 8c14f7a5 | * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * |
| 039e9fe0 | * FFmpeg is distributed in the hope that it will be useful, |
| 8c14f7a5 | * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public |
| 039e9fe0 | * License along with FFmpeg; if not, write to the Free Software |
| 8c14f7a5 |
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "libavutil/intreadwrite.h"
#include "avutil.h"
#include "common.h"
#include "xtea.h"
void av_xtea_init(AVXTEA *ctx, const uint8_t key[16])
{
int i;
for (i = 0; i < 4; i++)
ctx->key[i] = AV_RB32(key + (i << 2));
}
static void xtea_crypt_ecb(AVXTEA *ctx, uint8_t *dst, const uint8_t *src, |
| 48154c25 |
int decrypt, uint8_t *iv) |
| 8c14f7a5 |
{
uint32_t v0, v1; |
| c5bea1b0 | #if !CONFIG_SMALL |
| bb4ddeea |
uint32_t k0 = ctx->key[0];
uint32_t k1 = ctx->key[1];
uint32_t k2 = ctx->key[2];
uint32_t k3 = ctx->key[3]; |
| c5bea1b0 | #endif |
| 8c14f7a5 |
v0 = AV_RB32(src);
v1 = AV_RB32(src + 4);
if (decrypt) { |
| bb4ddeea |
#if CONFIG_SMALL
int i; |
| 43bbc3f4 |
uint32_t delta = 0x9E3779B9U, sum = delta * 32; |
| 8c14f7a5 |
for (i = 0; i < 32; i++) {
v1 -= (((v0 << 4) ^ (v0 >> 5)) + v0) ^ (sum + ctx->key[(sum >> 11) & 3]);
sum -= delta;
v0 -= (((v1 << 4) ^ (v1 >> 5)) + v1) ^ (sum + ctx->key[sum & 3]);
} |
| bb4ddeea |
#else
#define DSTEP(SUM, K0, K1) \
v1 -= (((v0 << 4) ^ (v0 >> 5)) + v0) ^ (SUM + K0); \ |
| 43bbc3f4 |
v0 -= (((v1 << 4) ^ (v1 >> 5)) + v1) ^ (SUM - 0x9E3779B9U + K1) |
| bb4ddeea |
DSTEP(0xC6EF3720U, k2, k3);
DSTEP(0x28B7BD67U, k3, k2);
DSTEP(0x8A8043AEU, k0, k1);
DSTEP(0xEC48C9F5U, k1, k0);
DSTEP(0x4E11503CU, k2, k3);
DSTEP(0xAFD9D683U, k2, k2);
DSTEP(0x11A25CCAU, k3, k1);
DSTEP(0x736AE311U, k0, k0);
DSTEP(0xD5336958U, k1, k3);
DSTEP(0x36FBEF9FU, k1, k2);
DSTEP(0x98C475E6U, k2, k1);
DSTEP(0xFA8CFC2DU, k3, k0);
DSTEP(0x5C558274U, k0, k3);
DSTEP(0xBE1E08BBU, k1, k2);
DSTEP(0x1FE68F02U, k1, k1);
DSTEP(0x81AF1549U, k2, k0);
DSTEP(0xE3779B90U, k3, k3);
DSTEP(0x454021D7U, k0, k2);
DSTEP(0xA708A81EU, k1, k1);
DSTEP(0x08D12E65U, k1, k0);
DSTEP(0x6A99B4ACU, k2, k3);
DSTEP(0xCC623AF3U, k3, k2);
DSTEP(0x2E2AC13AU, k0, k1);
DSTEP(0x8FF34781U, k0, k0);
DSTEP(0xF1BBCDC8U, k1, k3);
DSTEP(0x5384540FU, k2, k2);
DSTEP(0xB54CDA56U, k3, k1);
DSTEP(0x1715609DU, k0, k0);
DSTEP(0x78DDE6E4U, k0, k3);
DSTEP(0xDAA66D2BU, k1, k2);
DSTEP(0x3C6EF372U, k2, k1);
DSTEP(0x9E3779B9U, k3, k0); |
| a8cb21fd |
#endif
if (iv) { |
| b4345004 |
v0 ^= AV_RB32(iv);
v1 ^= AV_RB32(iv + 4); |
| 48154c25 |
memcpy(iv, src, 8);
} |
| 8c14f7a5 |
} else { |
| bb4ddeea |
#if CONFIG_SMALL
int i; |
| 43bbc3f4 |
uint32_t sum = 0, delta = 0x9E3779B9U; |
| 8c14f7a5 |
for (i = 0; i < 32; i++) {
v0 += (((v1 << 4) ^ (v1 >> 5)) + v1) ^ (sum + ctx->key[sum & 3]);
sum += delta;
v1 += (((v0 << 4) ^ (v0 >> 5)) + v0) ^ (sum + ctx->key[(sum >> 11) & 3]);
} |
| bb4ddeea |
#else
#define ESTEP(SUM, K0, K1) \
v0 += (((v1 << 4) ^ (v1 >> 5)) + v1) ^ (SUM + K0);\ |
| 43bbc3f4 |
v1 += (((v0 << 4) ^ (v0 >> 5)) + v0) ^ (SUM + 0x9E3779B9U + K1) |
| bb4ddeea |
ESTEP(0x00000000U, k0, k3);
ESTEP(0x9E3779B9U, k1, k2);
ESTEP(0x3C6EF372U, k2, k1);
ESTEP(0xDAA66D2BU, k3, k0);
ESTEP(0x78DDE6E4U, k0, k0);
ESTEP(0x1715609DU, k1, k3);
ESTEP(0xB54CDA56U, k2, k2);
ESTEP(0x5384540FU, k3, k1);
ESTEP(0xF1BBCDC8U, k0, k0);
ESTEP(0x8FF34781U, k1, k0);
ESTEP(0x2E2AC13AU, k2, k3);
ESTEP(0xCC623AF3U, k3, k2);
ESTEP(0x6A99B4ACU, k0, k1);
ESTEP(0x08D12E65U, k1, k1);
ESTEP(0xA708A81EU, k2, k0);
ESTEP(0x454021D7U, k3, k3);
ESTEP(0xE3779B90U, k0, k2);
ESTEP(0x81AF1549U, k1, k1);
ESTEP(0x1FE68F02U, k2, k1);
ESTEP(0xBE1E08BBU, k3, k0);
ESTEP(0x5C558274U, k0, k3);
ESTEP(0xFA8CFC2DU, k1, k2);
ESTEP(0x98C475E6U, k2, k1);
ESTEP(0x36FBEF9FU, k3, k1);
ESTEP(0xD5336958U, k0, k0);
ESTEP(0x736AE311U, k1, k3);
ESTEP(0x11A25CCAU, k2, k2);
ESTEP(0xAFD9D683U, k3, k2);
ESTEP(0x4E11503CU, k0, k1);
ESTEP(0xEC48C9F5U, k1, k0);
ESTEP(0x8A8043AEU, k2, k3);
ESTEP(0x28B7BD67U, k3, k2);
#endif |
| 8c14f7a5 |
}
AV_WB32(dst, v0);
AV_WB32(dst + 4, v1);
}
void av_xtea_crypt(AVXTEA *ctx, uint8_t *dst, const uint8_t *src, int count,
uint8_t *iv, int decrypt)
{
int i;
|
| f6687bf5 |
if (decrypt) { |
| 983db9b2 |
while (count--) { |
| 48154c25 |
xtea_crypt_ecb(ctx, dst, src, decrypt, iv); |
| f6687bf5 |
src += 8;
dst += 8;
}
} else { |
| 983db9b2 |
while (count--) { |
| 8c14f7a5 |
if (iv) {
for (i = 0; i < 8; i++)
dst[i] = src[i] ^ iv[i]; |
| 48154c25 |
xtea_crypt_ecb(ctx, dst, dst, decrypt, NULL); |
| 8c14f7a5 |
memcpy(iv, dst, 8);
} else { |
| 48154c25 |
xtea_crypt_ecb(ctx, dst, src, decrypt, NULL); |
| 8c14f7a5 |
} |
| f6687bf5 |
src += 8;
dst += 8; |
| 8c14f7a5 |
}
}
}
#ifdef TEST
#include <stdio.h>
#define XTEA_NUM_TESTS 6
static const uint8_t xtea_test_key[XTEA_NUM_TESTS][16] = {
{ 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f },
{ 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f },
{ 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f },
{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
{ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }
};
static const uint8_t xtea_test_pt[XTEA_NUM_TESTS][8] = {
{ 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48 },
{ 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41 },
{ 0x5a, 0x5b, 0x6e, 0x27, 0x89, 0x48, 0xd7, 0x7f },
{ 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48 },
{ 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41 },
{ 0x70, 0xe1, 0x22, 0x5d, 0x6e, 0x4e, 0x76, 0x55 }
};
static const uint8_t xtea_test_ct[XTEA_NUM_TESTS][8] = {
{ 0x49, 0x7d, 0xf3, 0xd0, 0x72, 0x61, 0x2c, 0xb5 },
{ 0xe7, 0x8f, 0x2d, 0x13, 0x74, 0x43, 0x41, 0xd8 },
{ 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41 },
{ 0xa0, 0x39, 0x05, 0x89, 0xf8, 0xb8, 0xef, 0xa5 },
{ 0xed, 0x23, 0x37, 0x5a, 0x82, 0x1a, 0x8c, 0x2d },
{ 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41 }
};
|
| ca074cc3 |
static void test_xtea(AVXTEA *ctx, uint8_t *dst, const uint8_t *src,
const uint8_t *ref, int len, uint8_t *iv, int dir,
const char *test)
{
av_xtea_crypt(ctx, dst, src, len, iv, dir);
if (memcmp(dst, ref, 8*len)) {
int i;
printf("%s failed\ngot ", test);
for (i = 0; i < 8*len; i++)
printf("%02x ", dst[i]);
printf("\nexpected ");
for (i = 0; i < 8*len; i++)
printf("%02x ", ref[i]);
printf("\n");
exit(1);
}
}
|
| 8c14f7a5 |
int main(void)
{
AVXTEA ctx; |
| a4dcdd04 |
uint8_t buf[8], iv[8]; |
| 8c14f7a5 |
int i; |
| a4dcdd04 |
const uint8_t src[32] = "HelloWorldHelloWorldHelloWorld"; |
| f0fce9f3 |
uint8_t ct[32];
uint8_t pl[32]; |
| a0321dad | |
| 8c14f7a5 |
for (i = 0; i < XTEA_NUM_TESTS; i++) {
av_xtea_init(&ctx, xtea_test_key[i]);
|
| ca074cc3 |
test_xtea(&ctx, buf, xtea_test_pt[i], xtea_test_ct[i], 1, NULL, 0, "encryption");
test_xtea(&ctx, buf, xtea_test_ct[i], xtea_test_pt[i], 1, NULL, 1, "decryption"); |
| 8c14f7a5 | |
| a4dcdd04 |
/* encrypt */
memcpy(iv, "HALLO123", 8);
av_xtea_crypt(&ctx, ct, src, 4, iv, 0);
/* decrypt into pl */
memcpy(iv, "HALLO123", 8); |
| f0fce9f3 |
test_xtea(&ctx, pl, ct, src, 4, iv, 1, "CBC decryption"); |
| a4dcdd04 |
memcpy(iv, "HALLO123", 8); |
| f0fce9f3 |
test_xtea(&ctx, ct, ct, src, 4, iv, 1, "CBC inplace decryption"); |
| 8c14f7a5 |
} |
| a4dcdd04 | |
| 8c14f7a5 |
printf("Test encryption/decryption success.\n");
return 0;
}
#endif |