Statistics
| Branch: | Revision:

ffmpeg / libavformat / base64.c @ 71e445fc

History | View | Annotate | Download (7.11 KB)

1
/*
2
 * Base64.c
3
 * Copyright (c) 2006 Ryan Martell. (rdm4@martellventures.com)
4
 *
5
 * This file is part of FFmpeg.
6
 *
7
 * FFmpeg is free software; you can redistribute it and/or
8
 * modify it under the terms of the GNU Lesser General Public
9
 * License as published by the Free Software Foundation; either
10
 * version 2.1 of the License, or (at your option) any later version.
11
 *
12
 * FFmpeg is distributed in the hope that it will be useful,
13
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15
 * Lesser General Public License for more details.
16
 *
17
 * You should have received a copy of the GNU Lesser General Public
18
 * License along with FFmpeg; if not, write to the Free Software
19
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20
 */
21

    
22
/**
23
* @file base64.c
24
 * @brief Base64 Encode/Decode
25
 * @author Ryan Martell <rdm4@martellventures.com> (with lots of Michael)
26
 */
27

    
28
#include "common.h"
29
#include "base64.h"
30

    
31
/* ---------------- private code */
32
static uint8_t map2[] =
33
{
34
    0x3e, 0xff, 0xff, 0xff, 0x3f, 0x34, 0x35, 0x36,
35
    0x37, 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0xff,
36
    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00, 0x01,
37
    0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09,
38
    0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 0x10, 0x11,
39
    0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19,
40
    0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x1a, 0x1b,
41
    0x1c, 0x1d, 0x1e, 0x1f, 0x20, 0x21, 0x22, 0x23,
42
    0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b,
43
    0x2c, 0x2d, 0x2e, 0x2f, 0x30, 0x31, 0x32, 0x33
44
};
45

    
46
int av_base64_decode(uint8_t * out, const char *in, int out_length)
47
{
48
    int i, v;
49
    uint8_t *dst = out;
50

    
51
    v = 0;
52
    for (i = 0; in[i] && in[i] != '='; i++) {
53
        unsigned int index= in[i]-43;
54
        if (index>=(sizeof(map2)/sizeof(map2[0])) || map2[index] == 0xff)
55
            return -1;
56
        v = (v << 6) + map2[index];
57
        if (i & 3) {
58
            if (dst - out < out_length) {
59
                *dst++ = v >> (6 - 2 * (i & 3));
60
            }
61
        }
62
    }
63

    
64
    return (dst - out);
65
}
66

    
67
/*****************************************************************************
68
* b64_encode: stolen from VLC's http.c
69
* simplified by michael
70
* fixed edge cases and made it work from data (vs. strings) by ryan.
71
*****************************************************************************/
72

    
73
char *av_base64_encode(uint8_t * src, int len)
74
{
75
    static const char b64[] =
76
        "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
77
    char *ret, *dst;
78
    unsigned i_bits = 0;
79
    int i_shift = 0;
80
    int bytes_remaining = len;
81

    
82
    if (len < UINT_MAX / 4) {
83
        ret = dst = av_malloc(len * 4 / 3 + 12);
84
    } else
85
        return NULL;
86

    
87
    if (len) {                  // special edge case, what should we really do here?
88
        while (bytes_remaining) {
89
            i_bits = (i_bits << 8) + *src++;
90
            bytes_remaining--;
91
            i_shift += 8;
92

    
93
            do {
94
                *dst++ = b64[(i_bits << 6 >> i_shift) & 0x3f];
95
                i_shift -= 6;
96
            } while (i_shift > 6 || (bytes_remaining == 0 && i_shift > 0));
97
        }
98
        while ((dst - ret) & 3)
99
            *dst++ = '=';
100
    }
101
    *dst = '\0';
102

    
103
    return ret;
104
}
105

    
106
// #define TEST_BASE64
107

    
108
#ifdef TEST_BASE64
109
#include "avutil.h"
110

    
111
int b64test()
112
{
113
    int numerr = 0;
114
    int len;
115
    int numtest = 1;
116
    uint8_t decode[1000];
117
    struct test {
118
        void *data;
119
        int len;
120
        const char *result;
121
    } *t, tests[] = {
122
        {
123
        "", 0, ""}, {
124
        "1", 1, "MQ=="}, {
125
        "22", 2, "MjI="}, {
126
        "333", 3, "MzMz"}, {
127
        "4444", 4, "NDQ0NA=="}, {
128
        "55555", 5, "NTU1NTU="}, {
129
        "abc:def", 7, "YWJjOmRlZg=="}, {
130
        NULL}
131
    };
132
    for (t = tests; t->data; t++) {
133
        char *str;
134

    
135
        av_log(NULL, AV_LOG_ERROR, "Encoding %s...\n", (char *) t->data);
136
        str = av_base64_encode(t->data, t->len);
137
        if (str) {
138
            av_log(NULL, AV_LOG_ERROR, "Encoded to %s...\n", str);
139
            if (strcmp(str, t->result) != 0) {
140
                av_log(NULL, AV_LOG_ERROR, "failed test %d: %s != %s\n",
141
                       numtest, str, t->result);
142
                numerr++;
143
            }
144
            av_free(str);
145
        }
146

    
147
        av_log(NULL, AV_LOG_ERROR, "Done encoding, about to decode...\n");
148
        len = av_base64_decode(decode, t->result, sizeof(decode));
149
        if (len != t->len) {
150
            av_log(NULL, AV_LOG_ERROR, "failed test %d: len %d != %d\n",
151
                   numtest, len, t->len);
152
            numerr++;
153
        } else if (memcmp(decode, t->data, t->len) != 0) {
154
            av_log(NULL, AV_LOG_ERROR, "failed test %d: data\n", numtest);
155
            numerr++;
156
        } else {
157
            av_log(NULL, AV_LOG_ERROR, "Decoded to %s\n",
158
                   (char *) t->data);
159
        }
160
        numtest++;
161
    }
162

    
163
#undef srand
164
#undef rand
165

    
166
    {
167
        int test_count;
168
        srand(123141);          // time(NULL));
169
        for (test_count = 0; test_count < 100; test_count++) {
170
            int size = rand() % 1024;
171
            int ii;
172
            uint8_t *data;
173
            char *encoded_result;
174

    
175
            av_log(NULL, AV_LOG_ERROR, "Test %d: Size %d bytes...",
176
                   test_count, size);
177
            data = (uint8_t *) av_malloc(size);
178
            for (ii = 0; ii < size; ii++) {
179
                data[ii] = rand() % 255;
180
            }
181

    
182
            encoded_result = av_base64_encode(data, size);
183
            if (encoded_result) {
184
                int decode_buffer_size = size + 10;     // try without 10 as well
185
                uint8_t *decode_buffer = av_malloc(decode_buffer_size);
186
                if (decode_buffer) {
187
                    int decoded_size =
188
                        av_base64_decode(decode_buffer, encoded_result,
189
                                   decode_buffer_size);
190

    
191
                    if (decoded_size != size) {
192
                        av_log(NULL, AV_LOG_ERROR,
193
                               "Decoded/Encoded size mismatch (%d != %d)\n",
194
                               decoded_size, size);
195
                    } else {
196
                        if (memcmp(decode_buffer, data, decoded_size) == 0) {
197
                            av_log(NULL, AV_LOG_ERROR, "Passed!\n");
198
                        } else {
199
                            av_log(NULL, AV_LOG_ERROR,
200
                                   "Failed (Data differs)!\n");
201
                        }
202
                    }
203
                    av_free(decode_buffer);
204
                }
205

    
206
                av_free(encoded_result);
207
            }
208
        }
209
    }
210

    
211
    // these are invalid strings, that it currently decodes (which it probably shouldn't?)
212
    {
213
        uint8_t str[32];
214
        if (av_base64_decode(str, "M=M=", sizeof(str)) != -1) {
215
            av_log(NULL, AV_LOG_ERROR,
216
                   "failed test %d: successful decode of `M=M='\n",
217
                   numtest++);
218
            numerr++;
219
        }
220
        if (av_base64_decode(str, "MQ===", sizeof(str)) != -1) {
221
            av_log(NULL, AV_LOG_ERROR,
222
                   "failed test %d: successful decode of `MQ==='\n",
223
                   numtest++);
224
            numerr++;
225
        }
226
    }
227

    
228
    return numerr;
229
}
230
#endif
231