aboutsummaryrefslogtreecommitdiffstats
path: root/smtpd/mfa.c
blob: f4d823f67a0d6d95e116ac965bd2144f95505050 (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
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
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
/*	$OpenBSD$	*/

/*
 * Copyright (c) 2008 Gilles Chehade <gilles@poolp.org>
 * Copyright (c) 2008 Pierre-Yves Ritschard <pyr@openbsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <sys/types.h>
#include <sys/wait.h>
#include <sys/queue.h>
#include <sys/tree.h>
#include <sys/socket.h>

#include <err.h>
#include <errno.h>
#include <event.h>
#include <imsg.h>
#include <pwd.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "smtpd.h"
#include "log.h"

static void mfa_imsg(struct mproc *, struct imsg *);
static void mfa_shutdown(void);
static void mfa_sig_handler(int, short, void *);

static void
mfa_imsg(struct mproc *p, struct imsg *imsg)
{
	struct sockaddr_storage	 local, remote;
	struct mailaddr		 maddr;
	struct msg		 m;
	const char		*line, *hostname;
	uint64_t		 reqid;
	int			 v;

	if (p->proc == PROC_SMTP) {
		switch (imsg->hdr.type) {
		case IMSG_MFA_REQ_CONNECT:
			m_msg(&m, imsg);
			m_get_id(&m, &reqid);
			m_get_sockaddr(&m, (struct sockaddr *)&local);
			m_get_sockaddr(&m, (struct sockaddr *)&remote);
			m_get_string(&m, &hostname);
			m_end(&m);
			mfa_filter_connect(reqid, (struct sockaddr *)&local,
			    (struct sockaddr *)&remote, hostname);
			return;

		case IMSG_MFA_REQ_HELO:
			m_msg(&m, imsg);
			m_get_id(&m, &reqid);
			m_get_string(&m, &line);
			m_end(&m);
			mfa_filter_line(reqid, HOOK_HELO, line);
			return;

		case IMSG_MFA_REQ_MAIL:
			m_msg(&m, imsg);
			m_get_id(&m, &reqid);
			m_get_mailaddr(&m, &maddr);
			m_end(&m);
			mfa_filter_mailaddr(reqid, HOOK_MAIL, &maddr);
			return;

		case IMSG_MFA_REQ_RCPT:
			m_msg(&m, imsg);
			m_get_id(&m, &reqid);
			m_get_mailaddr(&m, &maddr);
			m_end(&m);
			mfa_filter_mailaddr(reqid, HOOK_RCPT, &maddr);
			return;

		case IMSG_MFA_REQ_DATA:
			m_msg(&m, imsg);
			m_get_id(&m, &reqid);
			m_end(&m);
			mfa_filter(reqid, HOOK_DATA);
			return;

		case IMSG_MFA_REQ_EOM:
			m_msg(&m, imsg);
			m_get_id(&m, &reqid);
			m_end(&m);
			mfa_filter(reqid, HOOK_EOM);
			return;

		case IMSG_MFA_SMTP_DATA:
			m_msg(&m, imsg);
			m_get_id(&m, &reqid);
			m_get_string(&m, &line);
			m_end(&m);
			mfa_filter_data(reqid, line);
			return;

		case IMSG_MFA_EVENT_RSET:
			m_msg(&m, imsg);
			m_get_id(&m, &reqid);
			m_end(&m);
			mfa_filter_event(reqid, HOOK_RESET);
			return;

		case IMSG_MFA_EVENT_COMMIT:
			m_msg(&m, imsg);
			m_get_id(&m, &reqid);
			m_end(&m);
			mfa_filter_event(reqid, HOOK_COMMIT);
			return;

		case IMSG_MFA_EVENT_ROLLBACK:
			m_msg(&m, imsg);
			m_get_id(&m, &reqid);
			m_end(&m);
			mfa_filter_event(reqid, HOOK_ROLLBACK);
			return;

		case IMSG_MFA_EVENT_DISCONNECT:
			m_msg(&m, imsg);
			m_get_id(&m, &reqid);
			m_end(&m);
			mfa_filter_event(reqid, HOOK_DISCONNECT);
			return;
		}
	}

	if (p->proc == PROC_PARENT) {
		switch (imsg->hdr.type) {
		case IMSG_CONF_START:
			return;

		case IMSG_CONF_FILTER:
			return;

		case IMSG_CONF_END:
			mfa_filter_init();
			return;
			
		case IMSG_CTL_VERBOSE:
			m_msg(&m, imsg);
			m_get_int(&m, &v);
			m_end(&m);
			log_verbose(v);
			return;

		case IMSG_CTL_PROFILE:
			m_msg(&m, imsg);
			m_get_int(&m, &v);
			m_end(&m);
			profiling = v;
			return;
		}
	}

	errx(1, "mfa_imsg: unexpected %s imsg", imsg_to_str(imsg->hdr.type));
}

static void
mfa_sig_handler(int sig, short event, void *p)
{
	switch (sig) {
	case SIGINT:
	case SIGTERM:
		mfa_shutdown();
		break;

	case SIGCHLD:
		fatalx("unexpected SIGCHLD");
		break;

	default:
		fatalx("mfa_sig_handler: unexpected signal");
	}
}

static void
mfa_shutdown(void)
{
	pid_t pid;

	do {
		pid = waitpid(WAIT_MYPGRP, NULL, 0);
	} while (pid != -1 || (pid == -1 && errno == EINTR));

	log_info("info: mail filter exiting");
	_exit(0);
}

pid_t
mfa(void)
{
	pid_t		 pid;
	struct passwd	*pw;
	struct event	 ev_sigint;
	struct event	 ev_sigterm;
	struct event	 ev_sigchld;

	switch (pid = fork()) {
	case -1:
		fatal("mfa: cannot fork");
	case 0:
		break;
	default:
		return (pid);
	}

	mfa_filter_prepare();

	purge_config(PURGE_EVERYTHING);

	if ((pw =  getpwnam(SMTPD_USER)) == NULL)
		fatalx("unknown user " SMTPD_USER);

	config_process(PROC_MFA);

	if (chroot(PATH_CHROOT) == -1)
		fatal("scheduler: chroot");
	if (chdir("/") == -1)
		fatal("scheduler: chdir(\"/\")");

	if (setgroups(1, &pw->pw_gid) ||
	    setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) ||
	    setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid))
		fatal("mfa: cannot drop privileges");

	imsg_callback = mfa_imsg;
	event_init();

	signal_set(&ev_sigint, SIGINT, mfa_sig_handler, NULL);
	signal_set(&ev_sigterm, SIGTERM, mfa_sig_handler, NULL);
	signal_set(&ev_sigchld, SIGCHLD, mfa_sig_handler, NULL);
	signal_add(&ev_sigint, NULL);
	signal_add(&ev_sigterm, NULL);
	signal_add(&ev_sigchld, NULL);
	signal(SIGPIPE, SIG_IGN);
	signal(SIGHUP, SIG_IGN);

	config_peer(PROC_PARENT);
	config_peer(PROC_SMTP);
	config_peer(PROC_CONTROL);
	config_done();

	mproc_disable(p_smtp);

	if (event_dispatch() < 0)
		fatal("event_dispatch");
	mfa_shutdown();

	return (0);
}

void
mfa_ready(void)
{
	log_debug("debug: mfa ready");
	mproc_enable(p_smtp);
}