FFmpeg
tea.c
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1 /*
2  * A 32-bit implementation of the TEA algorithm
3  * Copyright (c) 2015 Vesselin Bontchev
4  *
5  * Loosely based on the implementation of David Wheeler and Roger Needham,
6  * https://en.wikipedia.org/wiki/Tiny_Encryption_Algorithm#Reference_code
7  *
8  * This file is part of FFmpeg.
9  *
10  * FFmpeg is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU Lesser General Public
12  * License as published by the Free Software Foundation; either
13  * version 2.1 of the License, or (at your option) any later version.
14  *
15  * FFmpeg is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18  * Lesser General Public License for more details.
19  *
20  * You should have received a copy of the GNU Lesser General Public
21  * License along with FFmpeg; if not, write to the Free Software
22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23  */
24 
25 #include <stdio.h>
26 
27 #include "libavutil/common.h"
28 #include "libavutil/tea.h"
29 
30 #define TEA_NUM_TESTS 4
31 
32 // https://github.com/logandrews/TeaCrypt/blob/master/tea/tea_test.go
33 static const uint8_t tea_test_key[TEA_NUM_TESTS][16] = {
34  { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
35  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
36  },
37  { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
38  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
39  },
40  { 0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77,
41  0x88, 0x99, 0xAA, 0xBB, 0xCC, 0xDD, 0xEE, 0xFF
42  },
43  { 0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77,
44  0x88, 0x99, 0xAA, 0xBB, 0xCC, 0xDD, 0xEE, 0xFF
45  }
46 };
47 
48 static const uint8_t tea_test_pt[TEA_NUM_TESTS][8] = {
49  { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
50  { 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08 },
51  { 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08 },
52  { 0x01, 0x23, 0x45, 0x67, 0x89, 0xAB, 0xCD, 0xEF }
53 };
54 
55 static const uint8_t tea_test_ct[TEA_NUM_TESTS][8] = {
56  { 0x41, 0xEA, 0x3A, 0x0A, 0x94, 0xBA, 0xA9, 0x40 },
57  { 0x6A, 0x2F, 0x9C, 0xF3, 0xFC, 0xCF, 0x3C, 0x55 },
58  { 0xDE, 0xB1, 0xC0, 0xA2, 0x7E, 0x74, 0x5D, 0xB3 },
59  { 0x12, 0x6C, 0x6B, 0x92, 0xC0, 0x65, 0x3A, 0x3E }
60 };
61 
62 static void test_tea(struct AVTEA *ctx, uint8_t *dst, const uint8_t *src,
63  const uint8_t *ref, int len, uint8_t *iv, int dir,
64  const char *test)
65 {
66  av_tea_crypt(ctx, dst, src, len, iv, dir);
67  if (memcmp(dst, ref, 8*len)) {
68  int i;
69  printf("%s failed\ngot ", test);
70  for (i = 0; i < 8*len; i++)
71  printf("%02x ", dst[i]);
72  printf("\nexpected ");
73  for (i = 0; i < 8*len; i++)
74  printf("%02x ", ref[i]);
75  printf("\n");
76  exit(1);
77  }
78 }
79 
80 int main(void)
81 {
82  struct AVTEA *ctx;
83  uint8_t buf[8], iv[8];
84  int i;
85  static const uint8_t src[32] = "HelloWorldHelloWorldHelloWorld";
86  uint8_t ct[32];
87  uint8_t pl[32];
88 
89  ctx = av_tea_alloc();
90  if (!ctx)
91  return 1;
92 
93  for (i = 0; i < TEA_NUM_TESTS; i++) {
95 
96  test_tea(ctx, buf, tea_test_pt[i], tea_test_ct[i], 1, NULL, 0, "encryption");
97  test_tea(ctx, buf, tea_test_ct[i], tea_test_pt[i], 1, NULL, 1, "decryption");
98 
99  /* encrypt */
100  memcpy(iv, "HALLO123", 8);
101  av_tea_crypt(ctx, ct, src, 4, iv, 0);
102 
103  /* decrypt into pl */
104  memcpy(iv, "HALLO123", 8);
105  test_tea(ctx, pl, ct, src, 4, iv, 1, "CBC decryption");
106 
107  memcpy(iv, "HALLO123", 8);
108  test_tea(ctx, ct, ct, src, 4, iv, 1, "CBC inplace decryption");
109  }
110 
111  printf("Test encryption/decryption success.\n");
112  av_free(ctx);
113 
114  return 0;
115 }
test_tea
static void test_tea(struct AVTEA *ctx, uint8_t *dst, const uint8_t *src, const uint8_t *ref, int len, uint8_t *iv, int dir, const char *test)
Definition: tea.c:62
test
Definition: idctdsp.c:35
av_tea_crypt
void av_tea_crypt(AVTEA *ctx, uint8_t *dst, const uint8_t *src, int count, uint8_t *iv, int decrypt)
Encrypt or decrypt a buffer using a previously initialized context.
Definition: tea.c:95
tea.h
Public header for libavutil TEA algorithm.
tea_test_key
static const uint8_t tea_test_key[TEA_NUM_TESTS][16]
Definition: tea.c:33
ctx
AVFormatContext * ctx
Definition: movenc.c:48
tea_test_pt
static const uint8_t tea_test_pt[TEA_NUM_TESTS][8]
Definition: tea.c:48
NULL
#define NULL
Definition: coverity.c:32
printf
printf("static const uint8_t my_array[100] = {\n")
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:255
common.h
len
int len
Definition: vorbis_enc_data.h:426
tea_test_ct
static const uint8_t tea_test_ct[TEA_NUM_TESTS][8]
Definition: tea.c:55
av_tea_init
void av_tea_init(AVTEA *ctx, const uint8_t key[16], int rounds)
Initialize an AVTEA context.
Definition: tea.c:42
main
int main(void)
Definition: tea.c:80
av_tea_alloc
struct AVTEA * av_tea_alloc(void)
Allocate an AVTEA context To free the struct: av_free(ptr)
Definition: tea.c:35
ref
static int ref[MAX_W *MAX_W]
Definition: jpeg2000dwt.c:112
av_free
#define av_free(p)
Definition: tableprint_vlc.h:33
src
INIT_CLIP pixel * src
Definition: h264pred_template.c:418
TEA_NUM_TESTS
#define TEA_NUM_TESTS
Definition: tea.c:30
AVTEA
Definition: tea.c:30