1 |
1026 |
ivang |
/*
|
2 |
|
|
* base64.c -- Base64 Mime encoding
|
3 |
|
|
*
|
4 |
|
|
* Copyright (c) GoAhead Software Inc., 1995-2000. All Rights Reserved.
|
5 |
|
|
*
|
6 |
|
|
* See the file "license.txt" for usage and redistribution license requirements
|
7 |
|
|
*/
|
8 |
|
|
|
9 |
|
|
/******************************** Description *********************************/
|
10 |
|
|
|
11 |
|
|
/*
|
12 |
|
|
* The base64 command encodes and decodes a string in mime base64 format
|
13 |
|
|
*/
|
14 |
|
|
|
15 |
|
|
/********************************* Includes ***********************************/
|
16 |
|
|
|
17 |
|
|
#include "wsIntrn.h"
|
18 |
|
|
|
19 |
|
|
/******************************** Local Data **********************************/
|
20 |
|
|
/*
|
21 |
|
|
* Mapping of ANSI chars to base64 Mime encoding alphabet (see below)
|
22 |
|
|
*/
|
23 |
|
|
|
24 |
|
|
static char_t map64[] = {
|
25 |
|
|
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
|
26 |
|
|
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, -1, -1, 63,
|
27 |
|
|
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
|
28 |
|
|
52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1,
|
29 |
|
|
-1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,
|
30 |
|
|
15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1,
|
31 |
|
|
-1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
|
32 |
|
|
41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1, -1, -1, -1,
|
33 |
|
|
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
|
34 |
|
|
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
|
35 |
|
|
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
|
36 |
|
|
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
|
37 |
|
|
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
|
38 |
|
|
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
|
39 |
|
|
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
|
40 |
|
|
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
|
41 |
|
|
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
|
42 |
|
|
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
|
43 |
|
|
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
|
44 |
|
|
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
|
45 |
|
|
};
|
46 |
|
|
|
47 |
|
|
static char_t alphabet64[] = {
|
48 |
|
|
'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H',
|
49 |
|
|
'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P',
|
50 |
|
|
'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X',
|
51 |
|
|
'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f',
|
52 |
|
|
'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n',
|
53 |
|
|
'o', 'p', 'q', 'r', 's', 't', 'u', 'v',
|
54 |
|
|
'w', 'x', 'y', 'z', '0', '1', '2', '3',
|
55 |
|
|
'4', '5', '6', '7', '8', '9', '+', '/',
|
56 |
|
|
};
|
57 |
|
|
|
58 |
|
|
/*********************************** Code *************************************/
|
59 |
|
|
/*
|
60 |
|
|
* Decode a buffer from "string" and into "outbuf"
|
61 |
|
|
*/
|
62 |
|
|
|
63 |
|
|
int websDecode64(char_t *outbuf, char_t *string, int outlen)
|
64 |
|
|
{
|
65 |
|
|
unsigned long shiftbuf;
|
66 |
|
|
char_t *cp, *op;
|
67 |
|
|
int c, i, j, shift;
|
68 |
|
|
|
69 |
|
|
op = outbuf;
|
70 |
|
|
*op = '\0';
|
71 |
|
|
cp = string;
|
72 |
|
|
while (*cp && *cp != '=') {
|
73 |
|
|
/*
|
74 |
|
|
* Map 4 (6bit) input bytes and store in a single long (shiftbuf)
|
75 |
|
|
*/
|
76 |
|
|
shiftbuf = 0;
|
77 |
|
|
shift = 18;
|
78 |
|
|
for (i = 0; i < 4 && *cp && *cp != '='; i++, cp++) {
|
79 |
|
|
c = map64[*cp & 0xff];
|
80 |
|
|
if (c == -1) {
|
81 |
|
|
error(E_L, E_LOG, T("Bad string: %s at %c index %d"), string,
|
82 |
|
|
c, i);
|
83 |
|
|
return -1;
|
84 |
|
|
}
|
85 |
|
|
shiftbuf = shiftbuf | (c << shift);
|
86 |
|
|
shift -= 6;
|
87 |
|
|
}
|
88 |
|
|
/*
|
89 |
|
|
* Interpret as 3 normal 8 bit bytes (fill in reverse order).
|
90 |
|
|
* Check for potential buffer overflow before filling.
|
91 |
|
|
*/
|
92 |
|
|
--i;
|
93 |
|
|
if ((op + i) >= &outbuf[outlen]) {
|
94 |
|
|
gstrcpy(outbuf, T("String too big"));
|
95 |
|
|
return -1;
|
96 |
|
|
}
|
97 |
|
|
for (j = 0; j < i; j++) {
|
98 |
|
|
*op++ = (char_t) ((shiftbuf >> (8 * (2 - j))) & 0xff);
|
99 |
|
|
}
|
100 |
|
|
*op = '\0';
|
101 |
|
|
}
|
102 |
|
|
return 0;
|
103 |
|
|
}
|
104 |
|
|
|
105 |
|
|
|
106 |
|
|
/******************************************************************************/
|
107 |
|
|
/*
|
108 |
|
|
* Encode a buffer from "string" into "outbuf"
|
109 |
|
|
*/
|
110 |
|
|
|
111 |
|
|
void websEncode64(char_t *outbuf, char_t *string, int outlen)
|
112 |
|
|
{
|
113 |
|
|
unsigned long shiftbuf;
|
114 |
|
|
char_t *cp, *op;
|
115 |
|
|
int x, i, j, shift;
|
116 |
|
|
|
117 |
|
|
op = outbuf;
|
118 |
|
|
*op = '\0';
|
119 |
|
|
cp = string;
|
120 |
|
|
while (*cp) {
|
121 |
|
|
/*
|
122 |
|
|
* Take three characters and create a 24 bit number in shiftbuf
|
123 |
|
|
*/
|
124 |
|
|
shiftbuf = 0;
|
125 |
|
|
for (j = 2; j >= 0 && *cp; j--, cp++) {
|
126 |
|
|
shiftbuf |= ((*cp & 0xff) << (j * 8));
|
127 |
|
|
}
|
128 |
|
|
/*
|
129 |
|
|
* Now convert shiftbuf to 4 base64 letters. The i,j magic calculates
|
130 |
|
|
* how many letters need to be output.
|
131 |
|
|
*/
|
132 |
|
|
shift = 18;
|
133 |
|
|
for (i = ++j; i < 4 && op < &outbuf[outlen] ; i++) {
|
134 |
|
|
x = (shiftbuf >> shift) & 0x3f;
|
135 |
|
|
*op++ = alphabet64[(shiftbuf >> shift) & 0x3f];
|
136 |
|
|
shift -= 6;
|
137 |
|
|
}
|
138 |
|
|
/*
|
139 |
|
|
* Pad at the end with '='
|
140 |
|
|
*/
|
141 |
|
|
while (j-- > 0) {
|
142 |
|
|
*op++ = '=';
|
143 |
|
|
}
|
144 |
|
|
*op = '\0';
|
145 |
|
|
}
|
146 |
|
|
}
|
147 |
|
|
/******************************************************************************/
|