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
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
|
/*
* This program is free software; you can redistribute it
* and/or modify it under the terms of the GNU General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later
* version.
*
* This program 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 General Public License for more
* details.
*
* You should have received a copy of the GNU General Public
* License along with this program; if not, write to the Free
* Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*
*/
/*
* Base64 handling elsewhere in mutt should be modified to call
* these routines. These routines were written because IMAP's
* AUTHENTICATE protocol required them, and base64 handling
* elsewhere wasn't sufficiently generic.
*
*/
/*
* This code is heavily modified from fetchmail (also GPL'd, of
* course) by Brendan Cully <brendan@kublai.com>.
*
* Original copyright notice:
*
* The code in the fetchmail distribution is Copyright 1997 by Eric
* S. Raymond. Portions are also copyrighted by Carl Harris, 1993
* and 1995. Copyright retained for the purpose of protecting free
* redistribution of source.
*
*/
#if HAVE_CONFIG_H
# include "config.h"
#endif
#include "mutt.h"
#include "mime.h"
#define BAD -1
void mutt_buffer_to_base64 (BUFFER *out, const unsigned char *in, size_t len)
{
mutt_buffer_increase_size (out,
((len * 2) > LONG_STRING) ? (len * 2) : LONG_STRING);
mutt_to_base64 ((unsigned char *)out->data, in, len, out->dsize);
mutt_buffer_fix_dptr (out);
}
static void to_base64 (unsigned char *out, const unsigned char *in, size_t len,
size_t olen, const char *dict)
{
while (len >= 3 && olen > 4)
{
*out++ = dict[in[0] >> 2];
*out++ = dict[((in[0] << 4) & 0x30) | (in[1] >> 4)];
*out++ = dict[((in[1] << 2) & 0x3c) | (in[2] >> 6)];
*out++ = dict[in[2] & 0x3f];
olen -= 4;
len -= 3;
in += 3;
}
/* clean up remainder */
if (len > 0 && olen > 4)
{
unsigned char fragment;
*out++ = dict[in[0] >> 2];
fragment = (in[0] << 4) & 0x30;
if (len > 1)
fragment |= in[1] >> 4;
*out++ = dict[fragment];
*out++ = (len < 2) ? '=' : dict[(in[1] << 2) & 0x3c];
*out++ = '=';
}
*out = '\0';
}
/* raw bytes to null-terminated base 64 string */
void mutt_to_base64 (unsigned char *out, const unsigned char *in, size_t len,
size_t olen)
{
to_base64 (out, in, len, olen, B64Chars);
}
void mutt_to_base64_safeurl (unsigned char *out, const unsigned char *in,
size_t len, size_t olen)
{
to_base64 (out, in, len, olen, B64Chars_urlsafe);
}
int mutt_buffer_from_base64 (BUFFER *out, const char *in)
{
int olen;
mutt_buffer_increase_size (out, mutt_strlen (in));
olen = mutt_from_base64 (out->data, in, out->dsize);
/* mutt_from_base64 returns raw bytes, so don't terminate the buffer either */
if (olen > 0)
out->dptr = out->data + olen;
else
out->dptr = out->data;
return olen;
}
/* Convert '\0'-terminated base 64 string to raw bytes.
* Returns length of returned buffer, or -1 on error */
int mutt_from_base64 (char *out, const char *in, size_t olen)
{
int len = 0;
register unsigned char digit1, digit2, digit3, digit4;
do
{
digit1 = in[0];
if (digit1 > 127 || base64val (digit1) == BAD)
return -1;
digit2 = in[1];
if (digit2 > 127 || base64val (digit2) == BAD)
return -1;
digit3 = in[2];
if (digit3 > 127 || ((digit3 != '=') && (base64val (digit3) == BAD)))
return -1;
digit4 = in[3];
if (digit4 > 127 || ((digit4 != '=') && (base64val (digit4) == BAD)))
return -1;
in += 4;
/* digits are already sanity-checked */
if (len == olen)
return len;
*out++ = (base64val(digit1) << 2) | (base64val(digit2) >> 4);
len++;
if (digit3 != '=')
{
if (len == olen)
return len;
*out++ = ((base64val(digit2) << 4) & 0xf0) | (base64val(digit3) >> 2);
len++;
if (digit4 != '=')
{
if (len == olen)
return len;
*out++ = ((base64val(digit3) << 6) & 0xc0) | base64val(digit4);
len++;
}
}
}
while (*in && digit4 != '=');
return len;
}
|