masqmail
view src/masqmail.c @ 407:164468dd0953
Minor refactoring.
author | markus schnalke <meillo@marmaro.de> |
---|---|
date | Wed, 29 Feb 2012 10:37:21 +0100 |
parents | 5781ba87df95 |
children | 6874a4f265c1 |
line source
1 /*
2 ** MasqMail
3 ** Copyright (C) 1999-2001 Oliver Kurth
4 ** Copyright (C) 2010 markus schnalke <meillo@marmaro.de>
5 **
6 ** This program is free software; you can redistribute it and/or modify
7 ** it under the terms of the GNU General Public License as published by
8 ** the Free Software Foundation; either version 2 of the License, or
9 ** (at your option) any later version.
10 **
11 ** This program is distributed in the hope that it will be useful,
12 ** but WITHOUT ANY WARRANTY; without even the implied warranty of
13 ** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 ** GNU General Public License for more details.
15 **
16 ** You should have received a copy of the GNU General Public License
17 ** along with this program; if not, write to the Free Software
18 ** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19 */
21 #include <stdio.h>
22 #include <errno.h>
23 #include <stdlib.h>
24 #include <string.h>
25 #include <unistd.h>
26 #include <sys/types.h>
27 #include <sys/socket.h>
28 #include <sys/time.h>
29 #include <netinet/in.h>
30 #include <netdb.h>
31 #include <syslog.h>
32 #include <signal.h>
34 #include <glib.h>
36 #include "masqmail.h"
38 /*
39 ** mutually exclusive modes. Note that there is no 'queue daemon' mode.
40 ** It, as well as the distinction beween the two (non exclusive) daemon
41 ** (queue and listen) modes, is handled by flags.
42 */
43 enum mta_mode {
44 MODE_NONE = 0, /* to check if a mode was set */
45 MODE_ACCEPT, /* accept message on stdin (fallback mode) */
46 MODE_DAEMON, /* run as daemon */
47 MODE_RUNQUEUE, /* single queue run, online or offline */
48 MODE_SMTP, /* accept SMTP on stdin */
49 MODE_LIST, /* list queue */
50 MODE_MCMD, /* do queue manipulation */
51 MODE_VERSION, /* show version */
52 MODE_BI, /* fake ;-) */
53 };
54 enum mta_mode mta_mode = MODE_NONE;
56 char *pidfile = NULL;
57 volatile int sigterm_in_progress = 0;
59 static void
60 sigterm_handler(int sig)
61 {
62 if (sigterm_in_progress)
63 raise(sig);
64 sigterm_in_progress = 1;
66 if (pidfile) {
67 uid_t uid = geteuid();
68 if (seteuid(0) != 0) {
69 logwrite(LOG_ALERT, "sigterm_handler: could not set euid to %d: %s\n", 0, strerror(errno));
70 }
71 if (unlink(pidfile) != 0)
72 logwrite(LOG_WARNING, "could not delete pid file %s: %s\n", pidfile, strerror(errno));
73 seteuid(uid); /* we exit anyway after this, just to be sure */
74 }
76 signal(sig, SIG_DFL);
77 raise(sig);
78 }
80 /*
81 ** argv: the original argv
82 ** argp: number of arg (may get modified!)
83 ** cp: pointing to the char after the option
84 ** e.g. `-d 6' `-d6'
85 ** ^ ^
86 */
87 gchar*
88 get_optarg(char *argv[], gint *argp, char *cp)
89 {
90 if (*cp) {
91 /* this kind: -xval */
92 return cp;
93 }
94 cp = argv[*argp+1];
95 if (cp && (*cp != '-')) {
96 /* this kind: -x val */
97 (*argp)++;
98 return cp;
99 }
100 return NULL;
101 }
103 gboolean
104 write_pidfile(gchar *name)
105 {
106 FILE *fptr;
108 if ((fptr = fopen(name, "wt"))) {
109 fprintf(fptr, "%d\n", getpid());
110 fclose(fptr);
111 pidfile = strdup(name);
112 return TRUE;
113 }
114 logwrite(LOG_WARNING, "could not write pid file: %s\n", strerror(errno));
115 return FALSE;
116 }
118 /* on -bd or if -q has an argument */
119 static void
120 mode_daemon(gboolean do_listen, gint queue_interval, char *argv[])
121 {
122 guint pid;
124 /* daemon */
125 if (!conf.run_as_user) {
126 if ((conf.orig_uid != 0) && (conf.orig_uid != conf.mail_uid)) {
127 fprintf(stderr, "must be root or %s for daemon.\n", DEF_MAIL_USER);
128 exit(1);
129 }
130 }
132 /* reparent to init only if init is not already the parent */
133 if (getppid() != 1) {
134 if ((pid = fork()) > 0) {
135 exit(0);
136 } else if (pid < 0) {
137 logwrite(LOG_ALERT, "could not fork!\n");
138 exit(1);
139 }
140 }
142 signal(SIGTERM, sigterm_handler);
143 write_pidfile(PIDFILEDIR "/masqmail.pid");
145 conf.do_verbose = FALSE;
147 /*
148 ** closing and reopening the log ensures that it is open afterwards
149 ** because it is possible that the log is assigned to fd 1 and gets
150 ** thus closes by fclose(stdout). Similar for the debugfile.
151 */
152 logclose();
153 fclose(stdin);
154 fclose(stdout);
155 fclose(stderr);
156 logopen();
158 logwrite(LOG_NOTICE, "%s %s daemon starting\n", PACKAGE, VERSION);
159 listen_port(do_listen ? conf.listen_addresses : NULL, queue_interval, argv);
160 }
162 /* -bs or called as smtpd or in.smtpd */
163 static void
164 mode_smtp()
165 {
166 /* accept smtp message on stdin */
167 /* write responses to stderr. */
169 struct sockaddr_in saddr;
170 gchar *peername = NULL;
171 int dummy = sizeof(saddr);
173 conf.do_verbose = FALSE;
175 if (!conf.run_as_user) {
176 set_euidgid(conf.orig_uid, conf.orig_gid, NULL, NULL);
177 }
179 DEBUG(5) debugf("accepting smtp message on stdin\n");
181 if (getpeername(0, (struct sockaddr *) (&saddr), &dummy) == 0) {
182 peername = g_strdup(inet_ntoa(saddr.sin_addr));
183 } else if (errno != ENOTSOCK)
184 exit(1);
186 smtp_in(stdin, stderr, peername, NULL);
187 }
189 /* default mode if address args or -t is specified, or called as rmail */
190 static void
191 mode_accept(address *return_path, gchar *full_sender_name, guint accept_flags,
192 char **addresses, int addr_cnt)
193 {
194 /* accept message on stdin */
195 accept_error err;
196 message *msg = create_message();
197 gint i;
198 pid_t pid;
200 if (return_path && !is_privileged_user(conf.orig_uid)) {
201 fprintf(stderr, "must be root, %s or in group %s for setting return path.\n", DEF_MAIL_USER, DEF_MAIL_GROUP);
202 exit(1);
203 }
205 if (!conf.run_as_user) {
206 set_euidgid(conf.orig_uid, conf.orig_gid, NULL, NULL);
207 }
209 DEBUG(5) debugf("accepting message on stdin\n");
211 msg->received_prot = PROT_LOCAL;
213 /* warn if -t option and cmdline addr args */
214 if (addr_cnt && (accept_flags & ACC_RCPT_FROM_HEAD)) {
215 logwrite(LOG_ALERT, "command line address arguments are now *added* to the mail header\\\n");
216 logwrite(LOG_ALERT, " recipient addresses (instead of substracted) when -t is given.\\\n");
217 logwrite(LOG_ALERT, " this changed with version 0.3.1\n");
218 }
220 for (i = 0; i < addr_cnt; i++) {
221 if (addresses[i][0] == '|') {
222 logwrite(LOG_ALERT, "no pipe allowed as recipient address: %s\n", addresses[i]);
223 /* should we better ignore this one addr? */
224 exit(1);
225 }
226 msg->rcpt_list = g_list_append(msg->rcpt_list, create_address_qualified(addresses[i], TRUE, conf.host_name));
227 }
229 /* -f option */
230 msg->return_path = return_path;
232 /* -F option */
233 msg->full_sender_name = full_sender_name;
235 err = accept_message(stdin, msg, accept_flags);
237 switch (err) {
238 case AERR_OK:
239 /* to continue; all other cases exit */
240 break;
241 case AERR_EOF:
242 fprintf(stderr, "unexpected EOF.\n");
243 exit(1);
244 case AERR_NORCPT:
245 fprintf(stderr, "no recipients.\n");
246 exit(1);
247 case AERR_SIZE:
248 fprintf(stderr, "max message size exceeded.\n");
249 exit(1);
250 default:
251 /* should never happen: */
252 fprintf(stderr, "Unknown error (%d)\r\n", err);
253 exit(1);
254 }
256 if (!spool_write(msg, TRUE)) {
257 fprintf(stderr, "Could not write spool file\n");
258 exit(1);
259 }
261 /* here the mail is queued and thus in our responsibility */
262 logwrite(LOG_NOTICE, "%s <= %s with %s\n", msg->uid, addr_string(msg->return_path), prot_names[PROT_LOCAL]);
264 if (conf.do_queue) {
265 /* we're finished as we only need to queue it */
266 return;
267 }
269 /* deliver at once */
270 if ((pid = fork()) < 0) {
271 logwrite(LOG_ALERT, "could not fork for delivery, id = %s\n", msg->uid);
272 } else if (pid == 0) {
273 conf.do_verbose = FALSE;
274 fclose(stdin);
275 fclose(stdout);
276 fclose(stderr);
277 if (deliver(msg)) {
278 exit(0);
279 } else {
280 /*
281 ** TODO: Should we really fail here? Because the
282 ** mail is queued already. If we fail the client
283 ** might submit it again. If at-once-delivery
284 ** is seen as an additional best-effort service,
285 ** then we should still exit successful here.
286 */
287 exit(1);
288 }
289 }
290 }
292 /*
293 ** if -Mrm is given
294 **
295 ** currently only the `rm' command is supported
296 ** until this changes, we don't need any facility for further commands
297 ** return success if at least one message had been deleted
298 */
299 static int
300 manipulate_queue(char *cmd, char *id[])
301 {
302 gboolean ok = FALSE;
304 if (strcmp(cmd, "rm") != 0) {
305 fprintf(stderr, "unknown command %s\n", cmd);
306 return FALSE;
307 }
309 set_euidgid(conf.mail_uid, conf.mail_gid, NULL, NULL);
311 /* privileged users may delete any mail */
312 if (is_privileged_user(conf.orig_uid)) {
313 for (; *id; id++) {
314 fprintf(stderr, "id: %s\n", *id);
315 if (queue_delete(*id)) {
316 ok = TRUE;
317 }
318 }
319 return ok;
320 }
322 struct passwd *pw = getpwuid(conf.orig_uid);
323 if (!pw) {
324 fprintf(stderr, "could not find a passwd entry for uid %d: %s\n",
325 conf.orig_uid, strerror(errno));
326 return FALSE;
327 }
329 /* non-privileged users may only delete their own messages */
330 for (; *id; id++) {
331 message *msg = msg_spool_read(*id);
333 fprintf(stderr, "id: %s\n", *id);
335 if (!msg->ident) {
336 fprintf(stderr, "message %s does not have an ident\n", *id);
337 continue;
338 }
339 if (strcmp(pw->pw_name, msg->ident) != 0) {
340 fprintf(stderr, "you do not own message id %s\n", *id);
341 continue;
342 }
344 if (msg->received_host || (msg->received_prot != PROT_LOCAL)) {
345 fprintf(stderr, "message %s was not received locally\n", *id);
346 continue;
347 }
349 ok = queue_delete(*id);
350 }
351 return ok;
352 }
354 /* -qo, -q (without argument), or called as runq */
355 static int
356 run_queue(gboolean do_runq, gboolean do_runq_online, char *route_name)
357 {
358 int ret;
360 /* queue runs */
361 set_identity(conf.orig_uid, "queue run");
363 if (do_runq) {
364 ret = queue_run();
365 }
367 if (do_runq_online) {
368 if (route_name) {
369 conf.online_query = g_strdup_printf("/bin/echo %s", route_name);
370 }
371 /*
372 ** TODO: change behavior of `-qo without argument'?
373 ** Because that behavior is included in -q.
374 */
375 ret = queue_run_online();
376 }
377 return ret;
378 }
380 /* -bV or default mode if neither addr arg nor -t */
381 static void
382 mode_version(void)
383 {
384 gchar *with_resolver = "";
385 gchar *with_auth = "";
387 #ifdef ENABLE_RESOLVER
388 with_resolver = " +resolver";
389 #endif
390 #ifdef ENABLE_AUTH
391 with_auth = " +auth";
392 #endif
394 printf("%s %s%s%s\n", PACKAGE, VERSION, with_resolver, with_auth);
395 }
397 void
398 set_mode(enum mta_mode mode)
399 {
400 if (mta_mode && mta_mode!=mode) {
401 fprintf(stderr, "operation mode was already specified (%d vs. %d)\n", mta_mode, mode);
402 exit(1);
403 }
405 mta_mode = mode;
406 return;
407 }
409 int
410 main(int argc, char *argv[])
411 {
412 gchar *progname;
413 char *opt;
414 gint arg;
416 gboolean do_listen = FALSE;
417 gboolean do_runq = FALSE;
418 gboolean do_runq_online = FALSE;
419 gboolean do_queue = FALSE;
420 gint queue_interval = 0;
421 gchar *M_cmd = NULL;
422 gboolean opt_t = FALSE;
423 gboolean opt_i = FALSE;
424 gchar *conf_file = CONF_FILE;
425 gchar *route_name = NULL;
426 gchar *f_address = NULL;
427 address *return_path = NULL; /* may be changed by -f option */
428 gchar *full_sender_name = NULL;
429 gboolean do_verbose = FALSE;
430 gint debug_level = -1;
432 /* strip the path part */
433 progname = strrchr(argv[0], '/');
434 progname = (progname) ? progname+1 : argv[0];
436 if (strcmp(progname, "mailq") == 0) {
437 mta_mode = MODE_LIST;
438 } else if (strcmp(progname, "mailrm") == 0) {
439 mta_mode = MODE_MCMD;
440 M_cmd = "rm";
441 } else if (strcmp(progname, "newaliases") == 0) {
442 mta_mode = MODE_BI;
443 } else if (strcmp(progname, "rmail") == 0) {
444 /*
445 ** the `rmail' alias should probably be removed now
446 ** that we have the rmail script. But let's keep it
447 ** for some while for compatibility. 2010-06-19
448 */
449 mta_mode = MODE_ACCEPT;
450 opt_i = TRUE;
451 } else if (strcmp(progname, "runq") == 0) {
452 mta_mode = MODE_RUNQUEUE;
453 do_runq = TRUE;
454 } else if (strcmp(progname, "smtpd") == 0
455 || strcmp(progname, "in.smtpd") == 0) {
456 mta_mode = MODE_SMTP;
457 }
459 /* parse cmd line */
460 for (arg=1; arg<argc && argv[arg][0]=='-'; arg++) {
461 opt = argv[arg] + 1; /* points to the char after the dash */
463 if (strcmp(opt, "-") == 0) {
464 /* everything after `--' are address arguments */
465 arg++;
466 break;
468 } else if (strcmp(opt, "bm") == 0) {
469 set_mode(MODE_ACCEPT);
471 } else if (strcmp(opt, "bd") == 0) {
472 set_mode(MODE_DAEMON);
473 do_listen = TRUE;
475 } else if (strcmp(opt, "bi") == 0) {
476 set_mode(MODE_BI);
478 } else if (strcmp(opt, "bs") == 0) {
479 set_mode(MODE_SMTP);
481 } else if (strcmp(opt, "bp") == 0) {
482 set_mode(MODE_LIST);
484 } else if (strcmp(opt, "bV") == 0) {
485 set_mode(MODE_VERSION);
487 } else if (strncmp(opt, "B", 1) == 0) {
488 /* we ignore this and throw the argument away */
489 get_optarg(argv, &arg, opt+1);
491 } else if (strncmp(opt, "C", 1) == 0) {
492 conf_file = get_optarg(argv, &arg, opt+1);
493 if (!conf_file) {
494 fprintf(stderr, "-C requires a filename as argument.\n");
495 exit(1);
496 }
498 } else if (strncmp(opt, "d", 1) == 0) {
499 if (getuid() != 0) {
500 fprintf(stderr, "only root may set the debug level.\n");
501 exit(1);
502 }
503 char *lvl = get_optarg(argv, &arg, opt+1);
504 if (!lvl) {
505 fprintf(stderr, "-d requires a number argument.\n");
506 exit(1);
507 }
508 debug_level = atoi(lvl);
510 } else if (strncmp(opt, "f", 1) == 0) {
511 /* set return path */
512 gchar *address = get_optarg(argv, &arg, opt+1);
513 if (!address) {
514 fprintf(stderr, "-f requires an address argument\n");
515 exit(1);
516 }
517 f_address = g_strdup(address);
519 } else if (strncmp(opt, "F", 1) == 0) {
520 full_sender_name = get_optarg(argv, &arg, opt+1);
521 if (!full_sender_name) {
522 fprintf(stderr, "-F requires a name argument\n");
523 exit(1);
524 }
526 } else if (strcmp(opt, "i") == 0) {
527 opt_i = TRUE;
529 } else if (strcmp(opt, "m") == 0) {
530 /* ignore -m (me too) switch (see man page) */
532 } else if (strcmp(opt, "Mrm") == 0) {
533 set_mode(MODE_MCMD);
534 M_cmd = "rm";
536 } else if (strcmp(opt, "odq") == 0) {
537 do_queue = TRUE;
539 } else if (strcmp(opt, "oi") == 0) {
540 opt_i = TRUE;
542 } else if (strncmp(opt, "o", 1) == 0) {
543 /* ignore all other -oXXX options */
545 } else if (strncmp(opt, "qo", 2) == 0) {
546 /* must be before the `q' check */
547 set_mode(MODE_RUNQUEUE);
548 do_runq_online = TRUE;
549 /* can be NULL, then we use online detection method */
550 /* TODO: behavior might change if it is NULL */
551 route_name = get_optarg(argv, &arg, opt+2);
552 if (!route_name) {
553 fprintf(stderr, "Please do not use -qo without argument anymore; use -q instead.\n");
554 fprintf(stderr, "The behavior for -qo without argument is likely to change.\n");
555 }
557 } else if (strncmp(opt, "q", 1) == 0) {
558 /* must be after the `qo' check */
559 gchar *optarg;
561 optarg = get_optarg(argv, &arg, opt+1);
562 if (optarg) {
563 /* not just one single queue run but regular runs */
564 set_mode(MODE_DAEMON);
565 queue_interval = time_interval(optarg);
566 } else {
567 set_mode(MODE_RUNQUEUE);
568 do_runq = TRUE;
569 }
571 } else if (strcmp(opt, "t") == 0) {
572 opt_t = TRUE;
574 } else if (strcmp(opt, "v") == 0) {
575 do_verbose = TRUE;
577 } else {
578 fprintf(stderr, "unrecognized option `-%s'\n", opt);
579 exit(1);
580 }
581 }
583 if (!mta_mode && arg==argc && !opt_t) {
584 /*
585 ** In this case no rcpts can be found, thus no mail
586 ** can be sent, thus masqmail will always fail. We
587 ** rather do something better instead. This covers
588 ** also the case of calling masqmail without args.
589 */
590 mode_version();
591 exit(0);
592 }
594 if (mta_mode == MODE_VERSION) {
595 mode_version();
596 exit(0);
597 }
599 if (!mta_mode) {
600 mta_mode = MODE_ACCEPT;
601 }
603 /* initialize random generator */
604 srand(time(NULL));
605 /* ignore SIGPIPE signal */
606 signal(SIGPIPE, SIG_IGN);
608 /* close all possibly open file descriptors, except std{in,out,err} */
609 {
610 int i, max_fd = sysconf(_SC_OPEN_MAX);
612 if (max_fd <= 0) {
613 max_fd = 64;
614 }
615 for (i=3; i<max_fd; i++) {
616 close(i);
617 }
618 }
620 init_conf();
622 /*
623 ** if we are not privileged, and the config file was changed we
624 ** implicetely set the the run_as_user flag and give up all
625 ** privileges.
626 **
627 ** So it is possible for a user to run his own daemon without
628 ** breaking security.
629 */
630 if ((strcmp(conf_file, CONF_FILE) != 0) && (conf.orig_uid != 0)) {
631 conf.run_as_user = TRUE;
632 set_euidgid(conf.orig_uid, conf.orig_gid, NULL, NULL);
633 if (setgid(conf.orig_gid)) {
634 logwrite(LOG_ALERT, "could not set gid to %d: %s\n", conf.orig_gid, strerror(errno));
635 exit(1);
636 }
637 if (setuid(conf.orig_uid)) {
638 logwrite(LOG_ALERT, "could not set uid to %d: %s\n", conf.orig_uid, strerror(errno));
639 exit(1);
640 }
641 }
643 conf.log_dir = LOG_DIR;
644 conf.debug_level = debug_level; /* for debuggin during read_conf() */
645 /* FIXME: fails if we run as user */
646 logopen();
647 if (!read_conf(conf_file)) {
648 logwrite(LOG_ALERT, "SHUTTING DOWN due to problems reading config\n");
649 exit(5);
650 }
651 logclose();
653 if (do_queue) {
654 conf.do_queue = TRUE;
655 }
656 if (do_verbose) {
657 conf.do_verbose = TRUE;
658 }
659 if (debug_level >= 0) { /* if >= 0, it was given by argument */
660 conf.debug_level = debug_level;
661 }
663 /*
664 ** It appears that changing to / ensures that we are never in
665 ** a directory which we cannot access. This situation could be
666 ** possible after changing identity.
667 ** Maybe we should only change to / if we not run as user, to
668 ** allow relative paths for log files in test setups for
669 ** instance.
670 */
671 chdir("/");
673 if (!conf.run_as_user) {
674 if (setgid(0) != 0) {
675 fprintf(stderr, "could not set gid to 0. Is the setuid bit set? : %s\n", strerror(errno));
676 exit(1);
677 }
678 if (setuid(0) != 0) {
679 fprintf(stderr, "could not gain root privileges. Is the setuid bit set? : %s\n", strerror(errno));
680 exit(1);
681 }
682 }
684 if (!logopen()) {
685 fprintf(stderr, "could not open log file\n");
686 exit(1);
687 }
689 DEBUG(1) debugf("masqmail %s starting\n", VERSION);
691 DEBUG(5) {
692 gchar **str = argv;
693 debugf("args: \n");
694 while (*str) {
695 debugf("%s \n", *str);
696 str++;
697 }
698 }
699 DEBUG(5) debugf("queue_interval = %d\n", queue_interval);
701 if (f_address) {
702 return_path = create_address_qualified(f_address, TRUE, conf.host_name);
703 g_free(f_address);
704 if (!return_path) {
705 fprintf(stderr, "invalid RFC821 address: %s\n", f_address);
706 exit(1);
707 }
708 }
710 switch (mta_mode) {
711 case MODE_DAEMON:
712 mode_daemon(do_listen, queue_interval, argv);
713 break;
715 case MODE_RUNQUEUE:
716 exit(run_queue(do_runq, do_runq_online, route_name) ? 0 : 1);
717 break;
719 case MODE_SMTP:
720 mode_smtp();
721 break;
723 case MODE_LIST:
724 queue_list();
725 break;
727 case MODE_BI:
728 exit(0);
729 break; /* well... */
731 case MODE_MCMD:
732 exit(manipulate_queue(M_cmd, &argv[arg]) ? 0 : 1);
733 break;
735 case MODE_ACCEPT:
736 {
737 guint accept_flags = (opt_t ? ACC_RCPT_FROM_HEAD : 0)
738 | (opt_i ? ACC_DOT_IGNORE : ACC_NODOT_RELAX);
739 mode_accept(return_path, full_sender_name, accept_flags, &(argv[arg]), argc - arg);
740 exit(0);
741 }
742 break;
744 default:
745 fprintf(stderr, "unknown mode: %d\n", mta_mode);
746 break;
747 }
749 logclose();
751 exit(0);
752 }