aboutsummaryrefslogtreecommitdiffstats
path: root/crm114-exec.c
blob: a10ba09b9debb10dfc51be20ac7a902f64c2edc5 (plain) (blame)
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
/*
 * crm114 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 "mail-storage-private.h"

#include "antispam-plugin.h"
#include "signature.h"

static const char *reaver_binary = "/bin/false";
static char **extra_args = NULL;
static int extra_args_num = 0;

#define FIXED_ARGS_NUM 2

static int call_reaver(const char *signature, enum classification wanted)
{
	pid_t pid;
	const char *class_arg;
	int pipes[2];

	switch (wanted) {
	case CLASS_NOTSPAM:
		class_arg = "--good";
		break;
	case CLASS_SPAM:
		class_arg = "--spam";
		break;
	}

	/*
	 * For reaver stdin, it wants to read a full message but
	 * really only needs the signature.
	 */
	if (pipe(pipes))
		return -1;

	pid = fork();
	if (pid < 0)
		return -1;

	if (pid) {
		int status;

		close(pipes[0]);

		/*
		 * Reaver wants the mail but only needs the cache ID
		 */
		write(pipes[1], signature_hdr, strlen(signature_hdr));
		write(pipes[1], ": ", 2);
		write(pipes[1], signature, strlen(signature));
		write(pipes[1], "\r\n\r\n", 4);
		close(pipes[1]);

		/*
		 * Wait for reaver
		 */
		waitpid(pid, &status, 0);
		if (!WIFEXITED(status))
			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 + 1);
		int i;

		argv = i_malloc(sz);
		memset(argv, 0, sz);

		close(0);
		close(1);
		close(2);
		/* see above */
		close(pipes[1]);

		if (dup2(pipes[0], 0) != 0)
			exit(1);
		close(pipes[0]);

		if (dup2(fd, 1) != 1)
			exit(1);
		if (dup2(fd, 2) != 2)
			exit(1);
		close(fd);

		argv[0] = (char *)reaver_binary;
		argv[1] = (char *)class_arg;

		debug("antispam: %s %s ...", reaver_binary, class_arg);

		for (i = 0; i < extra_args_num; i++)
			argv[i + FIXED_ARGS_NUM] = (char *)extra_args[i];

		execv(reaver_binary, argv);
		/* fall through if reaver 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 mailbox_transaction_context *ctx,
		   struct antispam_transaction_context *ast)
{
	struct siglist *item = ast->siglist;
	int ret = 0;

	while (item) {
		if (call_reaver(item->sig, item->wanted)) {
			ret = -1;
			mail_storage_set_error(ctx->box->storage,
					       "Failed to call reaver");
			break;
		}
		item = item->next;
	}

	signature_list_free(&ast->siglist);
	i_free(ast);
	return ret;
}

int backend_handle_mail(struct mailbox_transaction_context *t,
			struct antispam_transaction_context *ast,
			struct mail *mail, enum classification want)
{
	return signature_extract_to_list(t, mail, &ast->siglist, want);
}

void backend_init(pool_t pool)
{
	char *tmp;
	int i;

	tmp = getenv("ANTISPAM_CRM_BINARY");
	if (tmp) {
		reaver_binary = tmp;
		debug("antispam: reaver binary set to %s\n", tmp);
	}

	tmp = getenv("ANTISPAM_CRM_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: reaver extra arg %s\n",
			      extra_args[i]);
	}

	signature_init();
}

void backend_exit(void)
{
}