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authorTim Redfern <tim@eclectronics.org>2013-09-05 17:57:22 +0100
committerTim Redfern <tim@eclectronics.org>2013-09-05 17:57:22 +0100
commit8992cb1d0d07edc33d274f6d7924ecdf6f83d994 (patch)
tree3a2c86846b7eec8137c1507e623fc7018f13d453 /ffmpeg/libavutil/xtea.c
parent741fb4b9e135cfb161a749db88713229038577bb (diff)
making act segmenter
Diffstat (limited to 'ffmpeg/libavutil/xtea.c')
-rw-r--r--ffmpeg/libavutil/xtea.c274
1 files changed, 274 insertions, 0 deletions
diff --git a/ffmpeg/libavutil/xtea.c b/ffmpeg/libavutil/xtea.c
new file mode 100644
index 0000000..e729c91
--- /dev/null
+++ b/ffmpeg/libavutil/xtea.c
@@ -0,0 +1,274 @@
+/*
+ * A 32-bit implementation of the XTEA algorithm
+ * Copyright (c) 2012 Samuel Pitoiset
+ *
+ * loosely based on the implementation of David Wheeler and Roger Needham
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * 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.
+ *
+ * FFmpeg 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * 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,
+ int decrypt, uint8_t *iv)
+{
+ uint32_t v0, v1;
+#if !CONFIG_SMALL
+ uint32_t k0 = ctx->key[0];
+ uint32_t k1 = ctx->key[1];
+ uint32_t k2 = ctx->key[2];
+ uint32_t k3 = ctx->key[3];
+#endif
+
+ v0 = AV_RB32(src);
+ v1 = AV_RB32(src + 4);
+
+ if (decrypt) {
+#if CONFIG_SMALL
+ int i;
+ uint32_t delta = 0x9E3779B9U, sum = delta * 32;
+
+ 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]);
+ }
+#else
+#define DSTEP(SUM, K0, K1) \
+ v1 -= (((v0 << 4) ^ (v0 >> 5)) + v0) ^ (SUM + K0); \
+ v0 -= (((v1 << 4) ^ (v1 >> 5)) + v1) ^ (SUM - 0x9E3779B9U + K1)
+
+ 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);
+#endif
+ if (iv) {
+ v0 ^= AV_RB32(iv);
+ v1 ^= AV_RB32(iv + 4);
+ memcpy(iv, src, 8);
+ }
+ } else {
+#if CONFIG_SMALL
+ int i;
+ uint32_t sum = 0, delta = 0x9E3779B9U;
+
+ 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]);
+ }
+#else
+#define ESTEP(SUM, K0, K1) \
+ v0 += (((v1 << 4) ^ (v1 >> 5)) + v1) ^ (SUM + K0);\
+ v1 += (((v0 << 4) ^ (v0 >> 5)) + v0) ^ (SUM + 0x9E3779B9U + K1)
+ 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
+ }
+
+ 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;
+
+ if (decrypt) {
+ while (count--) {
+ xtea_crypt_ecb(ctx, dst, src, decrypt, iv);
+
+ src += 8;
+ dst += 8;
+ }
+ } else {
+ while (count--) {
+ if (iv) {
+ for (i = 0; i < 8; i++)
+ dst[i] = src[i] ^ iv[i];
+ xtea_crypt_ecb(ctx, dst, dst, decrypt, NULL);
+ memcpy(iv, dst, 8);
+ } else {
+ xtea_crypt_ecb(ctx, dst, src, decrypt, NULL);
+ }
+ src += 8;
+ dst += 8;
+ }
+ }
+}
+
+#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 }
+};
+
+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);
+ }
+}
+
+int main(void)
+{
+ AVXTEA ctx;
+ uint8_t buf[8], iv[8];
+ int i;
+ const uint8_t src[32] = "HelloWorldHelloWorldHelloWorld";
+ uint8_t ct[32];
+ uint8_t pl[32];
+
+ for (i = 0; i < XTEA_NUM_TESTS; i++) {
+ av_xtea_init(&ctx, xtea_test_key[i]);
+
+ 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");
+
+ /* encrypt */
+ memcpy(iv, "HALLO123", 8);
+ av_xtea_crypt(&ctx, ct, src, 4, iv, 0);
+
+ /* decrypt into pl */
+ memcpy(iv, "HALLO123", 8);
+ test_xtea(&ctx, pl, ct, src, 4, iv, 1, "CBC decryption");
+
+ memcpy(iv, "HALLO123", 8);
+ test_xtea(&ctx, ct, ct, src, 4, iv, 1, "CBC inplace decryption");
+ }
+
+ printf("Test encryption/decryption success.\n");
+
+ return 0;
+}
+
+#endif