1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
|
/*
* base64.c
* base64 encode/decode implementation
*
* Copyright (c) 2011 Nikias Bassen, All Rights Reserved.
*
* This library 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.
*
* This library 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 this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <string.h>
#include "base64.h"
static const char base64_str[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
static const char base64_pad = '=';
static const signed char base64_table[256] = {
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, -1, -1, 63,
52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1,
-1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,
15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1,
-1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1
};
char *base64encode(const unsigned char *buf, size_t *size)
{
if (!buf || !size || !(*size > 0)) return NULL;
int outlen = (*size / 3) * 4;
char *outbuf = (char*)malloc(outlen+5); // 4 spare bytes + 1 for '\0'
size_t n = 0;
size_t m = 0;
unsigned char input[3];
unsigned int output[4];
while (n < *size) {
input[0] = buf[n++];
input[1] = (n < *size) ? buf[n++] : 0;
input[2] = (n < *size) ? buf[n++] : 0;
output[0] = input[0] >> 2;
output[1] = ((input[0] & 3) << 4) + (input[1] >> 4);
output[2] = ((input[1] & 15) << 2) + (input[2] >> 6);
output[3] = input[2] & 63;
outbuf[m++] = base64_str[(int)output[0]];
outbuf[m++] = base64_str[(int)output[1]];
outbuf[m++] = base64_str[(int)output[2]];
outbuf[m++] = base64_str[(int)output[3]];
}
while ((m % 4) != 0) {
outbuf[m++] = base64_pad;
}
outbuf[m] = 0; // 0-termination!
*size = m;
return outbuf;
}
static int base64decode_block(unsigned char *target, const char *data, size_t data_size)
{
int w1,w2,w3,w4;
int n,i;
if (!data || (data_size <= 0)) {
return 0;
}
n = 0;
i = 0;
while (n < data_size-3) {
w1 = base64_table[(int)data[n]];
w2 = base64_table[(int)data[n+1]];
w3 = base64_table[(int)data[n+2]];
w4 = base64_table[(int)data[n+3]];
if (w2 >= 0) {
target[i++] = (char)((w1*4 + (w2 >> 4)) & 255);
}
if (w3 >= 0) {
target[i++] = (char)((w2*16 + (w3 >> 2)) & 255);
}
if (w4 >= 0) {
target[i++] = (char)((w3*64 + w4) & 255);
}
n+=4;
}
return i;
}
unsigned char *base64decode(const char *buf, size_t *size)
{
if (!buf) return;
size_t len = strlen(buf);
if (len <= 0) return;
unsigned char *outbuf = (unsigned char*)malloc((len/4)*3+3);
unsigned char *line;
int p = 0;
line = (unsigned char*)strtok((char*)buf, "\r\n\t ");
while (line) {
p+=base64decode_block(outbuf+p, line, strlen((char*)line));
// get next line of base64 encoded block
line = (unsigned char*)strtok(NULL, "\r\n\t ");
}
outbuf[p] = 0;
*size = p;
return outbuf;
}
|
