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
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
|
/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/*
* Copyright (C) 2002 Ximian, Inc.
*
* Authors: Jeffrey Stedfast <fejj@ximian.com>
* Michael Zucchi <notzed@ximian.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public
* License as published by the Free Software Foundation.
*
* 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., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/* canonicalisation filter, used for secure mime incoming and outgoing */
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <string.h>
#include <ctype.h>
#include "camel-mime-filter-canon.h"
static void filter (CamelMimeFilter *f, char *in, size_t len, size_t prespace,
char **out, size_t *outlen, size_t *outprespace);
static void complete (CamelMimeFilter *f, char *in, size_t len,
size_t prespace, char **out, size_t *outlen,
size_t *outprespace);
static void reset (CamelMimeFilter *f);
static void
camel_mime_filter_canon_class_init (CamelMimeFilterCanonClass *klass)
{
CamelMimeFilterClass *mime_filter_class = (CamelMimeFilterClass *) klass;
mime_filter_class->filter = filter;
mime_filter_class->complete = complete;
mime_filter_class->reset = reset;
}
CamelType
camel_mime_filter_canon_get_type (void)
{
static CamelType type = CAMEL_INVALID_TYPE;
if (type == CAMEL_INVALID_TYPE) {
type = camel_type_register (camel_mime_filter_get_type(), "CamelMimeFilterCanon",
sizeof (CamelMimeFilterCanon),
sizeof (CamelMimeFilterCanonClass),
(CamelObjectClassInitFunc) camel_mime_filter_canon_class_init,
NULL,
NULL,
NULL);
}
return type;
}
static void
filter(CamelMimeFilter *f, char *in, size_t len, size_t prespace, char **out, size_t *outlen, size_t *outprespace)
{
register unsigned char *inptr, c;
const unsigned char *inend, *start;
char *starto;
register char *o;
int lf = 0;
guint32 flags;
flags = ((CamelMimeFilterCanon *)f)->flags;
/* first, work out how much space we need */
inptr = in;
inend = in+len;
while (inptr < inend)
if (*inptr++ == '\n')
lf++;
/* worst case, extra 3 chars per line
"From \n" -> "=46rom \r\n"
We add 1 extra incase we're called from complete, when we didn't end in \n */
camel_mime_filter_set_size(f, len+lf*3+4, FALSE);
o = f->outbuf;
inptr = in;
start = inptr;
starto = o;
while (inptr < inend) {
/* first, check start of line, we always start at the start of the line */
c = *inptr;
if (flags & CAMEL_MIME_FILTER_CANON_FROM && c == 'F') {
inptr++;
if (inptr < inend-4) {
if (strncmp(inptr, "rom ", 4) == 0) {
*o++ = '=';
*o++ = '4';
*o++ = '6';
} else
*o++ = 'F';
*o++ = *inptr++;
*o++ = *inptr++;
*o++ = *inptr++;
*o++ = *inptr++;
} else {
break;
}
}
/* now scan for end of line */
while (inptr < inend) {
c = *inptr++;
if (c == '\n') {
/* check to strip trailing space */
if (flags & CAMEL_MIME_FILTER_CANON_STRIP) {
while (o>starto && (o[-1] == ' ' || o[-1] == '\t' || o[-1]=='\r'))
o--;
}
/* check end of line canonicalisation */
if (o>starto) {
if (flags & CAMEL_MIME_FILTER_CANON_CRLF) {
if (o[-1] != '\r')
*o++ = '\r';
} else {
if (o[-1] == '\r')
o--;
}
} else if (flags & CAMEL_MIME_FILTER_CANON_CRLF) {
/* empty line */
*o++ = '\r';
}
*o++ = c;
start = inptr;
starto = o;
break;
} else
*o++ = c;
}
}
/* TODO: We should probably track if we end somewhere in the middle of a line,
otherwise we potentially backup a full line, which could be large */
/* we got to the end of the data without finding anything, backup to start and re-process next time around */
camel_mime_filter_backup(f, start, inend - start);
*out = f->outbuf;
*outlen = starto - f->outbuf;
*outprespace = f->outpre;
}
static void
complete(CamelMimeFilter *f, char *in, size_t len, size_t prespace, char **out, size_t *outlen, size_t *outprespace)
{
unsigned char *inptr, *inend;
char *o, *starto;
guint32 flags;
if (len)
filter(f, in, len, prespace, out, outlen, outprespace);
/* the data didn't contain an eol or was too short for "From ", we only need to check for "From" and add an eol */
if (f->backlen) {
inptr = (unsigned char *)f->backbuf;
inend = (unsigned char *)f->backbuf + f->backlen;
starto = o = *out + *outlen;
flags = ((CamelMimeFilterCanon *)f)->flags;
/* Check any embedded "From " */
if (f->backlen >= 5
&& (flags & CAMEL_MIME_FILTER_CANON_FROM)
&& strcmp(inptr, "From ") == 0) {
strcpy(o, "=46rom ");
o += 7;
inptr += 5;
}
/* copy the rest of it */
while (inptr < inend)
*o++ = *inptr++;
/* check to strip trailing space */
if (flags & CAMEL_MIME_FILTER_CANON_STRIP) {
while (o>starto && (o[-1] == ' ' || o[-1] == '\t' || o[-1]=='\r'))
o--;
}
/* check end of line canonicalisation */
if (o>starto) {
if (flags & CAMEL_MIME_FILTER_CANON_CRLF) {
if (o[-1] != '\r')
*o++ = '\r';
} else {
if (o[-1] == '\r')
o--;
}
}
/* and always finish with an eol */
*o++ = '\n';
*outlen = o - *out;
f->backlen = 0;
}
}
static void
reset (CamelMimeFilter *f)
{
/* no-op */
}
CamelMimeFilter *
camel_mime_filter_canon_new(guint32 flags)
{
CamelMimeFilterCanon *chomp = CAMEL_MIME_FILTER_CANON (camel_object_new (CAMEL_MIME_FILTER_CANON_TYPE));
chomp->flags = flags;
return (CamelMimeFilter *) chomp;
}
|
