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
|
/*
* dspam backend for dovecot antispam plugin
*
* Copyright (C) 2004-2007 Johannes Berg <johannes@sipsolutions.net>
* 2006 Frank Cusack
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License Version 2 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
*/
#include <unistd.h>
#include <stdlib.h>
#include <sys/wait.h>
#include <fcntl.h>
#include "lib.h"
#include "antispam-plugin.h"
#include "signature.h"
static const char *dspam_binary = "/usr/bin/dspam";
static char **extra_args = NULL;
static int extra_args_num = 0;
#define FIXED_ARGS_NUM 6
static int call_dspam(pool_t pool, const char *signature, bool is_spam)
{
pid_t pid;
const char *class_arg;
const char *sign_arg;
int pipes[2];
sign_arg = t_strconcat("--signature=", signature, NULL);
if (is_spam)
class_arg = t_strconcat("--class=", "spam", NULL);
else
class_arg = t_strconcat("--class=", "innocent", NULL);
/*
* For dspam stderr; dspam seems to not always exit with a
* non-zero exit code on errors so we treat it as an error
* if it logged anything to stderr.
*/
pipe(pipes);
pid = fork();
if (pid < 0)
return -1;
if (pid) {
int status;
char buf[1024];
int readsize;
bool error = FALSE;
close(pipes[1]);
do {
readsize = read(pipes[0], buf, sizeof(buf));
if (readsize < 0) {
readsize = -1;
if (errno == EINTR)
readsize = -2;
}
/*
* readsize > 0 means that we read a message from
* dspam, -1 means we failed to read for some odd
* reason
*/
if (readsize > 0 || readsize == -1)
error = TRUE;
} while (readsize == -2 || readsize > 0);
/*
* Wait for dspam, should return instantly since we've
* already waited above (waiting for stderr to close)
*/
waitpid(pid, &status, 0);
if (!WIFEXITED(status))
error = TRUE;
close(pipes[0]);
if (error)
return 1;
return WEXITSTATUS(status);
} else {
int fd = open("/dev/null", O_RDONLY);
char **argv;
int sz = sizeof(char *) * (FIXED_ARGS_NUM + extra_args_num);
int i;
argv = p_malloc(pool, sz);
memset(argv, 0, sz);
close(0);
close(1);
close(2);
/* see above */
close(pipes[0]);
if (dup2(pipes[1], 2) != 2)
exit(1);
if (dup2(pipes[1], 1) != 1)
exit(1);
close(pipes[1]);
if (dup2(fd, 0) != 0)
exit(1);
close(fd);
argv[0] = (char *)dspam_binary;
argv[1] = "--source=error";
argv[2] = "--stdout";
argv[3] = (char *)class_arg;
argv[4] = (char *)sign_arg;
debug("antispam: %s --source=error --stdout %s %s ...",
dspam_binary, class_arg, sign_arg);
for (i = 0; i < extra_args_num; i++)
argv[i + 5] = (char *)extra_args[i];
execv(dspam_binary, argv);
/* fall through if dspam can't be found */
exit(127);
/* not reached */
return -1;
}
}
struct antispam_transaction_context {
struct siglist *siglist;
};
struct antispam_transaction_context *backend_start(struct mailbox *box)
{
struct antispam_transaction_context *ast;
ast = i_new(struct antispam_transaction_context, 1);
ast->siglist = NULL;
return ast;
}
void backend_rollback(struct antispam_transaction_context *ast)
{
signature_list_free(&ast->siglist);
i_free(ast);
}
int backend_commit(struct antispam_transaction_context *ast)
{
struct siglist *item = ast->siglist;
while (item) {
debug("antispam: got signature %s\n", item->sig);
item = item->next;
}
signature_list_free(&ast->siglist);
i_free(ast);
return 0;
}
int backend_handle_mail(struct mailbox_transaction_context *t,
struct antispam_transaction_context *ast,
struct mail *mail)
{
return signature_extract(t, mail, &ast->siglist);
}
#if 0
bool backend(pool_t pool, bool spam, struct strlist *sigs)
{
int ret;
/* got all signatures now, walk them passing to dspam */
while (sigs) {
ret = call_dspam(pool, sigs->str, spam);
if (ret)
return FALSE;
sigs = sigs->next;
}
return TRUE;
}
#endif
void backend_init(pool_t pool)
{
char *tmp;
int i;
tmp = getenv("ANTISPAM_DSPAM_BINARY");
if (tmp) {
dspam_binary = tmp;
debug("dspam binary set to %s\n", tmp);
}
tmp = getenv("ANTISPAM_DSPAM_ARGS");
if (tmp) {
extra_args = p_strsplit(pool, tmp, ";");
extra_args_num = str_array_length(
(const char *const *)extra_args);
for (i = 0; i < extra_args_num; i++)
debug("antispam: dspam extra arg %s\n",
extra_args[i]);
}
signature_init();
}
void backend_exit(void)
{
}
|
