xref: /openbsd-src/libexec/spamd/grey.c (revision 2b0358df1d88d06ef4139321dd05bd5e05d91eaf)
1 /*	$OpenBSD: grey.c,v 1.46 2009/02/25 19:00:36 beck Exp $	*/
2 
3 /*
4  * Copyright (c) 2004-2006 Bob Beck.  All rights reserved.
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 
19 #include <sys/types.h>
20 #include <sys/socket.h>
21 #include <sys/ioctl.h>
22 #include <sys/fcntl.h>
23 #include <sys/wait.h>
24 #include <net/if.h>
25 #include <netinet/in.h>
26 #include <net/pfvar.h>
27 #include <arpa/inet.h>
28 #include <ctype.h>
29 #include <db.h>
30 #include <err.h>
31 #include <errno.h>
32 #include <fcntl.h>
33 #include <pwd.h>
34 #include <signal.h>
35 #include <stdio.h>
36 #include <stdlib.h>
37 #include <string.h>
38 #include <syslog.h>
39 #include <time.h>
40 #include <unistd.h>
41 #include <netdb.h>
42 
43 #include "grey.h"
44 #include "sync.h"
45 
46 extern time_t passtime, greyexp, whiteexp, trapexp;
47 extern struct syslog_data sdata;
48 extern struct passwd *pw;
49 extern u_short cfg_port;
50 extern pid_t jail_pid;
51 extern FILE *trapcfg;
52 extern FILE *grey;
53 extern int debug;
54 extern int syncsend;
55 
56 /* From netinet/in.h, but only _KERNEL_ gets them. */
57 #define satosin(sa)	((struct sockaddr_in *)(sa))
58 #define satosin6(sa)	((struct sockaddr_in6 *)(sa))
59 int server_lookup4(struct sockaddr_in *, struct sockaddr_in *,
60     struct sockaddr_in *);
61 int server_lookup6(struct sockaddr_in6 *, struct sockaddr_in6 *,
62     struct sockaddr_in6 *);
63 
64 size_t whitecount, whitealloc;
65 size_t trapcount, trapalloc;
66 char **whitelist;
67 char **traplist;
68 
69 char *traplist_name = "spamd-greytrap";
70 char *traplist_msg = "\"Your address %A has mailed to spamtraps here\\n\"";
71 
72 pid_t db_pid = -1;
73 int pfdev;
74 
75 struct db_change {
76 	SLIST_ENTRY(db_change)	entry;
77 	char *			key;
78 	void *			data;
79 	size_t			dsiz;
80 	int			act;
81 };
82 
83 #define DBC_ADD 1
84 #define DBC_DEL 2
85 
86 /* db pending changes list */
87 SLIST_HEAD(, db_change) db_changes = SLIST_HEAD_INITIALIZER(db_changes);
88 
89 struct mail_addr {
90 	SLIST_ENTRY(mail_addr)	entry;
91 	char			addr[MAX_MAIL];
92 };
93 
94 /* list of suffixes that must match TO: */
95 SLIST_HEAD(, mail_addr) match_suffix = SLIST_HEAD_INITIALIZER(match_suffix);
96 char *alloweddomains_file = PATH_SPAMD_ALLOWEDDOMAINS;
97 
98 char *low_prio_mx_ip;
99 time_t startup;
100 
101 static char *pargv[11]= {
102 	"pfctl", "-p", "/dev/pf", "-q", "-t",
103 	"spamd-white", "-T", "replace", "-f" "-", NULL
104 };
105 
106 /* If the parent gets a signal, kill off the children and exit */
107 /* ARGSUSED */
108 static void
109 sig_term_chld(int sig)
110 {
111 	if (db_pid != -1)
112 		kill(db_pid, SIGTERM);
113 	if (jail_pid != -1)
114 		kill(jail_pid, SIGTERM);
115 	_exit(1);
116 }
117 
118 /*
119  * Greatly simplified version from spamd_setup.c  - only
120  * sends one blacklist to an already open stream. Has no need
121  * to collapse cidr ranges since these are only ever single
122  * host hits.
123  */
124 void
125 configure_spamd(char **addrs, size_t count, FILE *sdc)
126 {
127 	size_t i;
128 
129 	fprintf(sdc, "%s;", traplist_name);
130 	if (count != 0) {
131 		fprintf(sdc, "%s;", traplist_msg);
132 		for (i = 0; i < count; i++)
133 			fprintf(sdc, "%s/32;", addrs[i]);
134 	}
135 	fprintf(sdc, "\n");
136 	if (fflush(sdc) == EOF)
137 		syslog_r(LOG_DEBUG, &sdata, "configure_spamd: fflush failed (%m)");
138 }
139 
140 
141 /* Stolen from ftp-proxy */
142 int
143 server_lookup(struct sockaddr *client, struct sockaddr *proxy,
144     struct sockaddr *server)
145 {
146 	if (client->sa_family == AF_INET)
147 		return (server_lookup4(satosin(client), satosin(proxy),
148 		    satosin(server)));
149 
150 	if (client->sa_family == AF_INET6)
151 		return (server_lookup6(satosin6(client), satosin6(proxy),
152 		    satosin6(server)));
153 
154 	errno = EPROTONOSUPPORT;
155 	return (-1);
156 }
157 
158 int
159 server_lookup4(struct sockaddr_in *client, struct sockaddr_in *proxy,
160     struct sockaddr_in *server)
161 {
162 	struct pfioc_natlook pnl;
163 
164 	memset(&pnl, 0, sizeof pnl);
165 	pnl.direction = PF_OUT;
166 	pnl.af = AF_INET;
167 	pnl.proto = IPPROTO_TCP;
168 	memcpy(&pnl.saddr.v4, &client->sin_addr.s_addr, sizeof pnl.saddr.v4);
169 	memcpy(&pnl.daddr.v4, &proxy->sin_addr.s_addr, sizeof pnl.daddr.v4);
170 	pnl.sport = client->sin_port;
171 	pnl.dport = proxy->sin_port;
172 
173 	if (ioctl(pfdev, DIOCNATLOOK, &pnl) == -1)
174 		return (-1);
175 
176 	memset(server, 0, sizeof(struct sockaddr_in));
177 	server->sin_len = sizeof(struct sockaddr_in);
178 	server->sin_family = AF_INET;
179 	memcpy(&server->sin_addr.s_addr, &pnl.rdaddr.v4,
180 	    sizeof server->sin_addr.s_addr);
181 	server->sin_port = pnl.rdport;
182 
183 	return (0);
184 }
185 
186 int
187 server_lookup6(struct sockaddr_in6 *client, struct sockaddr_in6 *proxy,
188     struct sockaddr_in6 *server)
189 {
190 	struct pfioc_natlook pnl;
191 
192 	memset(&pnl, 0, sizeof pnl);
193 	pnl.direction = PF_OUT;
194 	pnl.af = AF_INET6;
195 	pnl.proto = IPPROTO_TCP;
196 	memcpy(&pnl.saddr.v6, &client->sin6_addr.s6_addr, sizeof pnl.saddr.v6);
197 	memcpy(&pnl.daddr.v6, &proxy->sin6_addr.s6_addr, sizeof pnl.daddr.v6);
198 	pnl.sport = client->sin6_port;
199 	pnl.dport = proxy->sin6_port;
200 
201 	if (ioctl(pfdev, DIOCNATLOOK, &pnl) == -1)
202 		return (-1);
203 
204 	memset(server, 0, sizeof(struct sockaddr_in6));
205 	server->sin6_len = sizeof(struct sockaddr_in6);
206 	server->sin6_family = AF_INET6;
207 	memcpy(&server->sin6_addr.s6_addr, &pnl.rdaddr.v6,
208 	    sizeof server->sin6_addr);
209 	server->sin6_port = pnl.rdport;
210 
211 	return (0);
212 }
213 
214 int
215 configure_pf(char **addrs, int count)
216 {
217 	FILE *pf = NULL;
218 	int i, pdes[2], status;
219 	pid_t pid;
220 	char *fdpath;
221 	struct sigaction sa;
222 
223 	sigfillset(&sa.sa_mask);
224 	sa.sa_flags = SA_RESTART;
225 	sa.sa_handler = sig_term_chld;
226 
227 	if (debug)
228 		fprintf(stderr, "configure_pf - device on fd %d\n", pfdev);
229 	if (pfdev < 1 || pfdev > 63)
230 		return(-1);
231 	if (asprintf(&fdpath, "/dev/fd/%d", pfdev) == -1)
232 		return(-1);
233 	pargv[2] = fdpath;
234 	if (pipe(pdes) != 0) {
235 		syslog_r(LOG_INFO, &sdata, "pipe failed (%m)");
236 		free(fdpath);
237 		fdpath = NULL;
238 		return(-1);
239 	}
240 	signal(SIGCHLD, SIG_DFL);
241 	switch (pid = fork()) {
242 	case -1:
243 		syslog_r(LOG_INFO, &sdata, "fork failed (%m)");
244 		free(fdpath);
245 		fdpath = NULL;
246 		close(pdes[0]);
247 		close(pdes[1]);
248 		sigaction(SIGCHLD, &sa, NULL);
249 		return(-1);
250 	case 0:
251 		/* child */
252 		close(pdes[1]);
253 		if (pdes[0] != STDIN_FILENO) {
254 			dup2(pdes[0], STDIN_FILENO);
255 			close(pdes[0]);
256 		}
257 		execvp(PATH_PFCTL, pargv);
258 		syslog_r(LOG_ERR, &sdata, "can't exec %s:%m", PATH_PFCTL);
259 		_exit(1);
260 	}
261 
262 	/* parent */
263 	free(fdpath);
264 	fdpath = NULL;
265 	close(pdes[0]);
266 	pf = fdopen(pdes[1], "w");
267 	if (pf == NULL) {
268 		syslog_r(LOG_INFO, &sdata, "fdopen failed (%m)");
269 		close(pdes[1]);
270 		sigaction(SIGCHLD, &sa, NULL);
271 		return(-1);
272 	}
273 	for (i = 0; i < count; i++)
274 		if (addrs[i] != NULL)
275 			fprintf(pf, "%s/32\n", addrs[i]);
276 	fclose(pf);
277 
278 	waitpid(pid, &status, 0);
279 	if (WIFEXITED(status) && WEXITSTATUS(status) != 0)
280 		syslog_r(LOG_ERR, &sdata, "%s returned status %d", PATH_PFCTL,
281 		    WEXITSTATUS(status));
282 	else if (WIFSIGNALED(status))
283 		syslog_r(LOG_ERR, &sdata, "%s died on signal %d", PATH_PFCTL,
284 		    WTERMSIG(status));
285 
286 	sigaction(SIGCHLD, &sa, NULL);
287 	return(0);
288 }
289 
290 char *
291 dequotetolower(const char *addr)
292 {
293 	static char buf[MAX_MAIL];
294 	char *cp;
295 
296 	if (*addr == '<')
297 		addr++;
298 	(void) strlcpy(buf, addr, sizeof(buf));
299 	cp = strrchr(buf, '>');
300 	if (cp != NULL && cp[1] == '\0')
301 		*cp = '\0';
302 	cp = buf;
303 	while (*cp != '\0') {
304 		*cp = tolower(*cp);
305 		cp++;
306 	}
307 	return(buf);
308 }
309 
310 void
311 readsuffixlists(void)
312 {
313 	FILE *fp;
314 	char *buf;
315 	size_t len;
316 	struct mail_addr *m;
317 
318 	while (!SLIST_EMPTY(&match_suffix)) {
319 		m = SLIST_FIRST(&match_suffix);
320 		SLIST_REMOVE_HEAD(&match_suffix, entry);
321 		free(m);
322 	}
323 	if ((fp = fopen(alloweddomains_file, "r")) != NULL) {
324 		while ((buf = fgetln(fp, &len))) {
325 			if (buf[len-1] == '\n')
326 				len--;
327 			if ((m = malloc(sizeof(struct mail_addr))) == NULL)
328 				goto bad;
329 			if ((len + 1) > sizeof(m->addr)) {
330 				syslog_r(LOG_ERR, &sdata,
331 				    "line too long in %s - file ignored",
332 				    alloweddomains_file);
333 				goto bad;
334 			}
335 			memcpy(m->addr, buf, len);
336 			m->addr[len]='\0';
337 			syslog_r(LOG_ERR, &sdata, "got suffix %s", m->addr);
338 			SLIST_INSERT_HEAD(&match_suffix, m, entry);
339 		}
340 	}
341 	return;
342 bad:
343 	while (!SLIST_EMPTY(&match_suffix)) {
344 	  	m = SLIST_FIRST(&match_suffix);
345 		SLIST_REMOVE_HEAD(&match_suffix, entry);
346 		free(m);
347 	}
348 }
349 
350 void
351 freeaddrlists(void)
352 {
353 	int i;
354 
355 	if (whitelist != NULL)
356 		for (i = 0; i < whitecount; i++) {
357 			free(whitelist[i]);
358 			whitelist[i] = NULL;
359 		}
360 	whitecount = 0;
361 	if (traplist != NULL) {
362 		for (i = 0; i < trapcount; i++) {
363 			free(traplist[i]);
364 			traplist[i] = NULL;
365 		}
366 	}
367 	trapcount = 0;
368 }
369 
370 /* validate, then add to list of addrs to whitelist */
371 int
372 addwhiteaddr(char *addr)
373 {
374 	struct addrinfo hints, *res;
375 
376 	memset(&hints, 0, sizeof(hints));
377 	hints.ai_family = AF_INET;		/*for now*/
378 	hints.ai_socktype = SOCK_DGRAM;		/*dummy*/
379 	hints.ai_protocol = IPPROTO_UDP;	/*dummy*/
380 	hints.ai_flags = AI_NUMERICHOST;
381 
382 	if (getaddrinfo(addr, NULL, &hints, &res) == 0) {
383 		if (whitecount == whitealloc) {
384 			char **tmp;
385 
386 			tmp = realloc(whitelist,
387 			    (whitealloc + 1024) * sizeof(char *));
388 			if (tmp == NULL) {
389 				freeaddrinfo(res);
390 				return(-1);
391 			}
392 			whitelist = tmp;
393 			whitealloc += 1024;
394 		}
395 		whitelist[whitecount] = strdup(addr);
396 		if (whitelist[whitecount] == NULL) {
397 			freeaddrinfo(res);
398 			return(-1);
399 		}
400 		whitecount++;
401 		freeaddrinfo(res);
402 	} else
403 		return(-1);
404 	return(0);
405 }
406 
407 /* validate, then add to list of addrs to traplist */
408 int
409 addtrapaddr(char *addr)
410 {
411 	struct addrinfo hints, *res;
412 
413 	memset(&hints, 0, sizeof(hints));
414 	hints.ai_family = AF_INET;		/*for now*/
415 	hints.ai_socktype = SOCK_DGRAM;		/*dummy*/
416 	hints.ai_protocol = IPPROTO_UDP;	/*dummy*/
417 	hints.ai_flags = AI_NUMERICHOST;
418 
419 	if (getaddrinfo(addr, NULL, &hints, &res) == 0) {
420 		if (trapcount == trapalloc) {
421 			char **tmp;
422 
423 			tmp = realloc(traplist,
424 			    (trapalloc + 1024) * sizeof(char *));
425 			if (tmp == NULL) {
426 				freeaddrinfo(res);
427 				return(-1);
428 			}
429 			traplist = tmp;
430 			trapalloc += 1024;
431 		}
432 		traplist[trapcount] = strdup(addr);
433 		if (traplist[trapcount] == NULL) {
434 			freeaddrinfo(res);
435 			return(-1);
436 		}
437 		trapcount++;
438 		freeaddrinfo(res);
439 	} else
440 		return(-1);
441 	return(0);
442 }
443 
444 static int
445 queue_change(char *key, char *data, size_t dsiz, int act)
446 {
447 	struct db_change *dbc;
448 
449 	if ((dbc = malloc(sizeof(*dbc))) == NULL) {
450 		syslog_r(LOG_DEBUG, &sdata, "malloc failed (queue change)");
451 		return(-1);
452 	}
453 	if ((dbc->key = strdup(key)) == NULL) {
454 		syslog_r(LOG_DEBUG, &sdata, "malloc failed (queue change)");
455 		free(dbc);
456 		return(-1);
457 	}
458 	if ((dbc->data = malloc(dsiz)) == NULL) {
459 		syslog_r(LOG_DEBUG, &sdata, "malloc failed (queue change)");
460 		free(dbc->key);
461 		free(dbc);
462 		return(-1);
463 	}
464 	memcpy(dbc->data, data, dsiz);
465 	dbc->dsiz = dsiz;
466 	dbc->act = act;
467 	syslog_r(LOG_DEBUG, &sdata,
468 	    "queueing %s of %s", ((act == DBC_ADD) ? "add" : "deletion"),
469 	    dbc->key);
470 	SLIST_INSERT_HEAD(&db_changes, dbc, entry);
471 	return(0);
472 }
473 
474 static int
475 do_changes(DB *db)
476 {
477 	DBT			dbk, dbd;
478 	struct db_change	*dbc;
479 	int ret = 0;
480 
481 	while (!SLIST_EMPTY(&db_changes)) {
482 		dbc = SLIST_FIRST(&db_changes);
483 		switch (dbc->act) {
484 		case DBC_ADD:
485 			memset(&dbk, 0, sizeof(dbk));
486 			dbk.size = strlen(dbc->key);
487 			dbk.data = dbc->key;
488 			memset(&dbd, 0, sizeof(dbd));
489 			dbd.size = dbc->dsiz;
490 			dbd.data = dbc->data;
491 			if (db->put(db, &dbk, &dbd, 0)) {
492 				db->sync(db, 0);
493 				syslog_r(LOG_ERR, &sdata,
494 				    "can't add %s to spamd db (%m)", dbc->key);
495 				ret = -1;
496 			}
497 			db->sync(db, 0);
498 			break;
499 		case DBC_DEL:
500 			memset(&dbk, 0, sizeof(dbk));
501 			dbk.size = strlen(dbc->key);
502 			dbk.data = dbc->key;
503 			if (db->del(db, &dbk, 0)) {
504 				syslog_r(LOG_ERR, &sdata,
505 				    "can't delete %s from spamd db (%m)",
506 				    dbc->key);
507 				ret = -1;
508 			}
509 			break;
510 		default:
511 			syslog_r(LOG_ERR, &sdata, "Unrecognized db change");
512 			ret = -1;
513 		}
514 		free(dbc->key);
515 		dbc->key = NULL;
516 		free(dbc->data);
517 		dbc->data = NULL;
518 		dbc->act = 0;
519 		dbc->dsiz = 0;
520 		SLIST_REMOVE_HEAD(&db_changes, entry);
521 		free(dbc);
522 
523 	}
524 	return(ret);
525 }
526 
527 int
528 db_notin(DB *db, char *key)
529 {
530 	int			i;
531 	DBT			dbk, dbd;
532 
533 	memset(&dbk, 0, sizeof(dbk));
534 	dbk.size = strlen(key);
535 	dbk.data = key;
536 	memset(&dbd, 0,
537  sizeof(dbd));
538 	i = db->get(db, &dbk, &dbd, 0);
539 	if (i == -1)
540 		return (-1);
541 	if (i)
542 		/* not in the database */
543 		return (1);
544 	else
545 		/* it is in the database */
546 		return (0);
547 }
548 
549 
550 int
551 greyscan(char *dbname)
552 {
553 	HASHINFO	hashinfo;
554 	DBT		dbk, dbd;
555 	DB		*db;
556 	struct gdata	gd;
557 	int		r;
558 	char		*a = NULL;
559 	size_t		asiz = 0;
560 	time_t now = time(NULL);
561 
562 	/* walk db, expire, and whitelist */
563 	memset(&hashinfo, 0, sizeof(hashinfo));
564 	db = dbopen(dbname, O_EXLOCK|O_RDWR, 0600, DB_HASH, &hashinfo);
565 	if (db == NULL) {
566 		syslog_r(LOG_INFO, &sdata, "dbopen failed (%m)");
567 		return(-1);
568 	}
569 	memset(&dbk, 0, sizeof(dbk));
570 	memset(&dbd, 0, sizeof(dbd));
571 	for (r = db->seq(db, &dbk, &dbd, R_FIRST); !r;
572 	    r = db->seq(db, &dbk, &dbd, R_NEXT)) {
573 		if ((dbk.size < 1) || dbd.size != sizeof(struct gdata)) {
574 			syslog_r(LOG_ERR, &sdata, "bogus entry in spamd database");
575 			goto bad;
576 		}
577 		if (asiz < dbk.size + 1) {
578 			char *tmp;
579 
580 			tmp = realloc(a, dbk.size * 2);
581 			if (tmp == NULL)
582 				goto bad;
583 			a = tmp;
584 			asiz = dbk.size * 2;
585 		}
586 		memset(a, 0, asiz);
587 		memcpy(a, dbk.data, dbk.size);
588 		memcpy(&gd, dbd.data, sizeof(gd));
589 		if (gd.expire <= now && gd.pcount != -2) {
590 			/* get rid of entry */
591 			if (queue_change(a, NULL, 0, DBC_DEL) == -1)
592 				goto bad;
593 		} else if (gd.pcount == -1)  {
594 			/* this is a greytrap hit */
595 			if ((addtrapaddr(a) == -1) &&
596 			    (queue_change(a, NULL, 0, DBC_DEL) == -1))
597 				goto bad;
598 		} else if (gd.pcount >= 0 && gd.pass <= now) {
599 			int tuple = 0;
600 			char *cp;
601 
602 			/*
603 			 * add address to whitelist
604 			 * add an address-keyed entry to db
605 			 */
606 			cp = strchr(a, '\n');
607 			if (cp != NULL) {
608 				tuple = 1;
609 				*cp = '\0';
610 			}
611 
612 			if (addwhiteaddr(a) == -1) {
613 				if (cp != NULL)
614 					*cp = '\n';
615 				if (queue_change(a, NULL, 0, DBC_DEL) == -1)
616 					goto bad;
617 			}
618 
619 			if (tuple && db_notin(db, a)) {
620 				if (cp != NULL)
621 					*cp = '\0';
622 				/* re-add entry, keyed only by ip */
623 				gd.expire = now + whiteexp;
624 				dbd.size = sizeof(gd);
625 				dbd.data = &gd;
626 				if (queue_change(a, (void *) &gd, sizeof(gd),
627 				    DBC_ADD) == -1)
628 					goto bad;
629 				syslog_r(LOG_DEBUG, &sdata,
630 				    "whitelisting %s in %s", a, dbname);
631 			}
632 			if (debug)
633 				fprintf(stderr, "whitelisted %s\n", a);
634 		}
635 	}
636 	(void) do_changes(db);
637 	db->close(db);
638 	db = NULL;
639 	configure_pf(whitelist, whitecount);
640 	configure_spamd(traplist, trapcount, trapcfg);
641 
642 	freeaddrlists();
643 	free(a);
644 	a = NULL;
645 	asiz = 0;
646 	return(0);
647  bad:
648 	(void) do_changes(db);
649 	db->close(db);
650 	db = NULL;
651 	freeaddrlists();
652 	free(a);
653 	a = NULL;
654 	asiz = 0;
655 	return(-1);
656 }
657 
658 int
659 trapcheck(DB *db, char *to)
660 {
661 	int			i, j, smatch = 0;
662 	DBT			dbk, dbd;
663 	struct mail_addr	*m;
664 	char *			trap;
665 	size_t			s;
666 
667 	trap = dequotetolower(to);
668 	if (!SLIST_EMPTY(&match_suffix)) {
669 		s = strlen(trap);
670 		SLIST_FOREACH(m, &match_suffix, entry) {
671 			j = s - strlen(m->addr);
672 			if ((j >= 0) && (strcasecmp(trap+j, m->addr) == 0))
673 				smatch = 1;
674 		}
675 		if (!smatch)
676 			/* no suffixes match, so trap it */
677 			return (0);
678 	}
679 	memset(&dbk, 0, sizeof(dbk));
680 	dbk.size = strlen(trap);
681 	dbk.data = trap;
682 	memset(&dbd, 0, sizeof(dbd));
683 	i = db->get(db, &dbk, &dbd, 0);
684 	if (i == -1)
685 		return (-1);
686 	if (i)
687 		/* didn't exist - so this doesn't match a known spamtrap  */
688 		return (1);
689 	else
690 		/* To: address is a spamtrap, so add as a greytrap entry */
691 		return (0);
692 }
693 
694 int
695 twupdate(char *dbname, char *what, char *ip, char *source, char *expires)
696 {
697 	/* we got a TRAP or WHITE update from someone else */
698 	HASHINFO	hashinfo;
699 	DBT		dbk, dbd;
700 	DB		*db;
701 	struct gdata	gd;
702 	time_t		now, expire;
703 	int		r, spamtrap;
704 
705 	now = time(NULL);
706 	/* expiry times have to be in the future */
707 	expire = strtonum(expires, now, INT_MAX, NULL);
708 	if (expire == 0)
709 		return(-1);
710 
711 	if (strcmp(what, "TRAP") == 0)
712 		spamtrap = 1;
713 	else if (strcmp(what, "WHITE") == 0)
714 		spamtrap = 0;
715 	else
716 		return(-1);
717 
718 	memset(&hashinfo, 0, sizeof(hashinfo));
719 	db = dbopen(dbname, O_EXLOCK|O_RDWR, 0600, DB_HASH, &hashinfo);
720 	if (db == NULL)
721 		return(-1);
722 
723 	memset(&dbk, 0, sizeof(dbk));
724 	dbk.size = strlen(ip);
725 	dbk.data = ip;
726 	memset(&dbd, 0, sizeof(dbd));
727 	r = db->get(db, &dbk, &dbd, 0);
728 	if (r == -1)
729 		goto bad;
730 	if (r) {
731 		/* new entry */
732 		memset(&gd, 0, sizeof(gd));
733 		gd.first = now;
734 		gd.pcount = spamtrap ? -1 : 0;
735 		gd.expire = expire;
736 		memset(&dbk, 0, sizeof(dbk));
737 		dbk.size = strlen(ip);
738 		dbk.data = ip;
739 		memset(&dbd, 0, sizeof(dbd));
740 		dbd.size = sizeof(gd);
741 		dbd.data = &gd;
742 		r = db->put(db, &dbk, &dbd, 0);
743 		db->sync(db, 0);
744 		if (r)
745 			goto bad;
746 		if (debug)
747 			fprintf(stderr, "added %s %s\n",
748 			    spamtrap ? "trap entry for" : "", ip);
749 		syslog_r(LOG_DEBUG, &sdata,
750 		    "new %s from %s for %s, expires %s", what, source, ip,
751 		    expires);
752 	} else {
753 		/* existing entry */
754 		if (dbd.size != sizeof(gd)) {
755 			/* whatever this is, it doesn't belong */
756 			db->del(db, &dbk, 0);
757 			db->sync(db, 0);
758 			goto bad;
759 		}
760 		memcpy(&gd, dbd.data, sizeof(gd));
761 		if (spamtrap) {
762 			gd.pcount = -1;
763 			gd.bcount++;
764 		} else
765 			gd.pcount++;
766 		memset(&dbk, 0, sizeof(dbk));
767 		dbk.size = strlen(ip);
768 		dbk.data = ip;
769 		memset(&dbd, 0, sizeof(dbd));
770 		dbd.size = sizeof(gd);
771 		dbd.data = &gd;
772 		r = db->put(db, &dbk, &dbd, 0);
773 		db->sync(db, 0);
774 		if (r)
775 			goto bad;
776 		if (debug)
777 			fprintf(stderr, "updated %s\n", ip);
778 	}
779 	db->close(db);
780 	return(0);
781  bad:
782 	db->close(db);
783 	return(-1);
784 
785 }
786 
787 int
788 greyupdate(char *dbname, char *helo, char *ip, char *from, char *to, int sync,
789     char *cip)
790 {
791 	HASHINFO	hashinfo;
792 	DBT		dbk, dbd;
793 	DB		*db;
794 	char		*key = NULL;
795 	char		*lookup;
796 	struct gdata	gd;
797 	time_t		now, expire;
798 	int		r, spamtrap;
799 
800 	now = time(NULL);
801 
802 	/* open with lock, find record, update, close, unlock */
803 	memset(&hashinfo, 0, sizeof(hashinfo));
804 	db = dbopen(dbname, O_EXLOCK|O_RDWR, 0600, DB_HASH, &hashinfo);
805 	if (db == NULL)
806 		return(-1);
807 	if (asprintf(&key, "%s\n%s\n%s\n%s", ip, helo, from, to) == -1)
808 		goto bad;
809 	r = trapcheck(db, to);
810 	switch (r) {
811 	case 1:
812 		/* do not trap */
813 		spamtrap = 0;
814 		lookup = key;
815 		expire = greyexp;
816 		break;
817 	case 0:
818 		/* trap */
819 		spamtrap = 1;
820 		lookup = ip;
821 		expire = trapexp;
822 		syslog_r(LOG_DEBUG, &sdata, "Trapping %s for tuple %s", ip,
823 		    key);
824 		break;
825 	default:
826 		goto bad;
827 		break;
828 	}
829 	memset(&dbk, 0, sizeof(dbk));
830 	dbk.size = strlen(lookup);
831 	dbk.data = lookup;
832 	memset(&dbd, 0, sizeof(dbd));
833 	r = db->get(db, &dbk, &dbd, 0);
834 	if (r == -1)
835 		goto bad;
836 	if (r) {
837 		/* new entry */
838 		if (sync &&  low_prio_mx_ip &&
839 		    (strcmp(cip, low_prio_mx_ip) == 0) &&
840 		    ((startup + 60)  < now)) {
841 			/* we haven't seen a greylist entry for this tuple,
842 			 * and yet the connection was to a low priority MX
843 			 * which we know can't be hit first if the client
844 			 * is adhering to the RFC's - soo.. kill it!
845 			 */
846 			spamtrap = 1;
847 			lookup = ip;
848 			expire = trapexp;
849 			syslog_r(LOG_DEBUG, &sdata,
850 			    "Trapping %s for trying %s first for tuple %s",
851 			    ip, low_prio_mx_ip, key);
852 		}
853 		memset(&gd, 0, sizeof(gd));
854 		gd.first = now;
855 		gd.bcount = 1;
856 		gd.pcount = spamtrap ? -1 : 0;
857 		gd.pass = now + expire;
858 		gd.expire = now + expire;
859 		memset(&dbk, 0, sizeof(dbk));
860 		dbk.size = strlen(lookup);
861 		dbk.data = lookup;
862 		memset(&dbd, 0, sizeof(dbd));
863 		dbd.size = sizeof(gd);
864 		dbd.data = &gd;
865 		r = db->put(db, &dbk, &dbd, 0);
866 		db->sync(db, 0);
867 		if (r)
868 			goto bad;
869 		if (debug)
870 			fprintf(stderr, "added %s %s\n",
871 			    spamtrap ? "greytrap entry for" : "", lookup);
872 		syslog_r(LOG_DEBUG, &sdata,
873 		    "new %sentry %s from %s to %s, helo %s",
874 		    spamtrap ? "greytrap " : "", ip, from, to, helo);
875 	} else {
876 		/* existing entry */
877 		if (dbd.size != sizeof(gd)) {
878 			/* whatever this is, it doesn't belong */
879 			db->del(db, &dbk, 0);
880 			db->sync(db, 0);
881 			goto bad;
882 		}
883 		memcpy(&gd, dbd.data, sizeof(gd));
884 		gd.bcount++;
885 		gd.pcount = spamtrap ? -1 : 0;
886 		if (gd.first + passtime < now)
887 			gd.pass = now;
888 		memset(&dbk, 0, sizeof(dbk));
889 		dbk.size = strlen(lookup);
890 		dbk.data = lookup;
891 		memset(&dbd, 0, sizeof(dbd));
892 		dbd.size = sizeof(gd);
893 		dbd.data = &gd;
894 		r = db->put(db, &dbk, &dbd, 0);
895 		db->sync(db, 0);
896 		if (r)
897 			goto bad;
898 		if (debug)
899 			fprintf(stderr, "updated %s\n", lookup);
900 	}
901 	free(key);
902 	key = NULL;
903 	db->close(db);
904 	db = NULL;
905 
906 	/* Entry successfully update, sent out sync message */
907 	if (syncsend && sync) {
908 		if (spamtrap) {
909 			syslog_r(LOG_DEBUG, &sdata,
910 			    "sync_trap %s", ip);
911 			sync_trapped(now, now + expire, ip);
912 		}
913 		else
914 			sync_update(now, helo, ip, from, to);
915 	}
916 	return(0);
917  bad:
918 	free(key);
919 	key = NULL;
920 	db->close(db);
921 	db = NULL;
922 	return(-1);
923 }
924 
925 int
926 twread(char *buf)
927 {
928 	if ((strncmp(buf, "WHITE:", 6) == 0) ||
929 	    (strncmp(buf, "TRAP:", 5) == 0)) {
930 		char **ap, *argv[5];
931 		int argc = 0;
932 
933 		for (ap = argv;
934 		    ap < &argv[4] && (*ap = strsep(&buf, ":")) != NULL;) {
935 			if (**ap != '\0')
936 				ap++;
937 			argc++;
938 		}
939 		*ap = NULL;
940 		if (argc != 4)
941 			return (-1);
942 		twupdate(PATH_SPAMD_DB, argv[0], argv[1], argv[2], argv[3]);
943 		return (0);
944 	} else
945 		return (-1);
946 }
947 
948 int
949 greyreader(void)
950 {
951 	char cip[32], ip[32], helo[MAX_MAIL], from[MAX_MAIL], to[MAX_MAIL];
952 	char *buf;
953 	size_t len;
954 	int state, sync;
955 	struct addrinfo hints, *res;
956 
957 	memset(&hints, 0, sizeof(hints));
958 	hints.ai_family = AF_INET;		/*for now*/
959 	hints.ai_socktype = SOCK_DGRAM;		/*dummy*/
960 	hints.ai_protocol = IPPROTO_UDP;	/*dummy*/
961 	hints.ai_flags = AI_NUMERICHOST;
962 
963 	state = 0;
964 	sync = 1;
965 	if (grey == NULL) {
966 		syslog_r(LOG_ERR, &sdata, "No greylist pipe stream!\n");
967 		exit(1);
968 	}
969 
970 	/* grab trap suffixes */
971 	readsuffixlists();
972 
973 	while ((buf = fgetln(grey, &len))) {
974 		if (buf[len - 1] == '\n')
975 			buf[len - 1] = '\0';
976 		else
977 			/* all valid lines end in \n */
978 			continue;
979 		if (strlen(buf) < 4)
980 			continue;
981 
982 		if (strcmp(buf, "SYNC") == 0) {
983 			sync = 0;
984 			continue;
985 		}
986 
987 		switch (state) {
988 		case 0:
989 			if (twread(buf) == 0) {
990 				state = 0;
991 				break;
992 			}
993 			if (strncmp(buf, "HE:", 3) != 0) {
994 				if (strncmp(buf, "CO:", 3) == 0)
995 					strlcpy(cip, buf+3, sizeof(cip));
996 				state = 0;
997 				break;
998 			}
999 			strlcpy(helo, buf+3, sizeof(helo));
1000 			state = 1;
1001 			break;
1002 		case 1:
1003 			if (strncmp(buf, "IP:", 3) != 0)
1004 				break;
1005 			strlcpy(ip, buf+3, sizeof(ip));
1006 			if (getaddrinfo(ip, NULL, &hints, &res) == 0) {
1007 				freeaddrinfo(res);
1008 				state = 2;
1009 			} else
1010 				state = 0;
1011 			break;
1012 		case 2:
1013 			if (strncmp(buf, "FR:", 3) != 0) {
1014 				state = 0;
1015 				break;
1016 			}
1017 			strlcpy(from, buf+3, sizeof(from));
1018 			state = 3;
1019 			break;
1020 		case 3:
1021 			if (strncmp(buf, "TO:", 3) != 0) {
1022 				state = 0;
1023 				break;
1024 			}
1025 			strlcpy(to, buf+3, sizeof(to));
1026 			if (debug)
1027 				fprintf(stderr,
1028 				    "Got Grey HELO %s, IP %s from %s to %s\n",
1029 				    helo, ip, from, to);
1030 			greyupdate(PATH_SPAMD_DB, helo, ip, from, to, sync, cip);
1031 			sync = 1;
1032 			state = 0;
1033 			break;
1034 		}
1035 	}
1036 	return (0);
1037 }
1038 
1039 void
1040 greyscanner(void)
1041 {
1042 	for (;;) {
1043 		if (greyscan(PATH_SPAMD_DB) == -1)
1044 			syslog_r(LOG_NOTICE, &sdata, "scan of %s failed",
1045 			    PATH_SPAMD_DB);
1046 		sleep(DB_SCAN_INTERVAL);
1047 	}
1048 	/* NOTREACHED */
1049 }
1050 
1051 static void
1052 drop_privs(void)
1053 {
1054 	/*
1055 	 * lose root, continue as non-root user
1056 	 */
1057 	if (pw) {
1058 		setgroups(1, &pw->pw_gid);
1059 		setegid(pw->pw_gid);
1060 		setgid(pw->pw_gid);
1061 		seteuid(pw->pw_uid);
1062 		setuid(pw->pw_uid);
1063 	}
1064 }
1065 
1066 static void
1067 convert_spamd_db(void)
1068 {
1069 	char		sfn[] = "/var/db/spamd.XXXXXXXXX";
1070 	int		r, fd = -1;
1071 	DB		*db1, *db2;
1072 	BTREEINFO	btreeinfo;
1073 	HASHINFO	hashinfo;
1074 	DBT		dbk, dbd;
1075 
1076 	/* try to open the db as a BTREE */
1077 	memset(&btreeinfo, 0, sizeof(btreeinfo));
1078 	db1 = dbopen(PATH_SPAMD_DB, O_EXLOCK|O_RDWR, 0600, DB_BTREE,
1079 	    &btreeinfo);
1080 	if (db1 == NULL) {
1081 		syslog_r(LOG_ERR, &sdata,
1082 		    "corrupt db in %s, remove and restart", PATH_SPAMD_DB);
1083 		exit(1);
1084 	}
1085 
1086 	if ((fd = mkstemp(sfn)) == -1) {
1087 		syslog_r(LOG_ERR, &sdata,
1088 		    "can't convert %s: mkstemp failed (%m)", PATH_SPAMD_DB);
1089 		exit(1);
1090 	}
1091 	memset(&hashinfo, 0, sizeof(hashinfo));
1092 	db2 = dbopen(sfn, O_EXLOCK|O_RDWR, 0600, DB_HASH, &hashinfo);
1093 	if (db2 == NULL) {
1094 		unlink(sfn);
1095 		syslog_r(LOG_ERR, &sdata,
1096 		    "can't convert %s:  can't dbopen %s (%m)", PATH_SPAMD_DB,
1097 		sfn);
1098 		db1->close(db1);
1099 		exit(1);
1100 	}
1101 
1102 	memset(&dbk, 0, sizeof(dbk));
1103 	memset(&dbd, 0, sizeof(dbd));
1104 		for (r = db1->seq(db1, &dbk, &dbd, R_FIRST); !r;
1105 		    r = db1->seq(db1, &dbk, &dbd, R_NEXT)) {
1106 			if (db2->put(db2, &dbk, &dbd, 0)) {
1107 				db2->sync(db2, 0);
1108 				db2->close(db2);
1109 				db1->close(db1);
1110 				unlink(sfn);
1111 				syslog_r(LOG_ERR, &sdata,
1112 				    "can't convert %s - remove and restart",
1113 				    PATH_SPAMD_DB);
1114 				exit(1);
1115 			}
1116 		}
1117 	db2->sync(db2, 0);
1118 	db2->close(db2);
1119 	db1->sync(db1, 0);
1120 	db1->close(db1);
1121 	rename(sfn, PATH_SPAMD_DB);
1122 	close(fd);
1123 	/* if we are dropping privs, chown to that user */
1124 	if (pw && (chown(PATH_SPAMD_DB, pw->pw_uid, pw->pw_gid) == -1)) {
1125 		syslog_r(LOG_ERR, &sdata,
1126 		    "chown %s failed (%m)", PATH_SPAMD_DB);
1127 		exit(1);
1128 	}
1129 }
1130 
1131 static void
1132 check_spamd_db(void)
1133 {
1134 	HASHINFO hashinfo;
1135 	int i = -1;
1136 	DB *db;
1137 
1138 	/* check to see if /var/db/spamd exists, if not, create it */
1139 	memset(&hashinfo, 0, sizeof(hashinfo));
1140 	db = dbopen(PATH_SPAMD_DB, O_EXLOCK|O_RDWR, 0600, DB_HASH, &hashinfo);
1141 
1142 	if (db == NULL) {
1143 		switch (errno) {
1144 		case ENOENT:
1145 			i = open(PATH_SPAMD_DB, O_RDWR|O_CREAT, 0644);
1146 			if (i == -1) {
1147 				syslog_r(LOG_ERR, &sdata,
1148 				    "create %s failed (%m)", PATH_SPAMD_DB);
1149 				exit(1);
1150 			}
1151 			/* if we are dropping privs, chown to that user */
1152 			if (pw && (fchown(i, pw->pw_uid, pw->pw_gid) == -1)) {
1153 				syslog_r(LOG_ERR, &sdata,
1154 				    "chown %s failed (%m)", PATH_SPAMD_DB);
1155 				exit(1);
1156 			}
1157 			close(i);
1158 			drop_privs();
1159 			return;
1160 			break;
1161 		case EFTYPE:
1162 			/*
1163 			 * db may be old BTREE instead of HASH, attempt to
1164 			 * convert.
1165 			 */
1166 			convert_spamd_db();
1167 			drop_privs();
1168 			return;
1169 			break;
1170 		default:
1171 			syslog_r(LOG_ERR, &sdata, "open of %s failed (%m)",
1172 			    PATH_SPAMD_DB);
1173 			exit(1);
1174 		}
1175 	}
1176 	db->sync(db, 0);
1177 	db->close(db);
1178 	drop_privs();
1179 }
1180 
1181 
1182 int
1183 greywatcher(void)
1184 {
1185 	struct sigaction sa;
1186 
1187 	check_spamd_db();
1188 
1189 	startup = time(NULL);
1190 	db_pid = fork();
1191 	switch (db_pid) {
1192 	case -1:
1193 		syslog_r(LOG_ERR, &sdata, "fork failed (%m)");
1194 		exit(1);
1195 	case 0:
1196 		/*
1197 		 * child, talks to jailed spamd over greypipe,
1198 		 * updates db. has no access to pf.
1199 		 */
1200 		close(pfdev);
1201 		setproctitle("(%s update)", PATH_SPAMD_DB);
1202 		greyreader();
1203 		syslog_r(LOG_ERR, &sdata, "greyreader failed (%m)");
1204 		/* NOTREACHED */
1205 		_exit(1);
1206 	}
1207 
1208 
1209 	fclose(grey);
1210 	/*
1211 	 * parent, scans db periodically for changes and updates
1212 	 * pf whitelist table accordingly.
1213 	 */
1214 
1215 	sigfillset(&sa.sa_mask);
1216 	sa.sa_flags = SA_RESTART;
1217 	sa.sa_handler = sig_term_chld;
1218 	sigaction(SIGTERM, &sa, NULL);
1219 	sigaction(SIGHUP, &sa, NULL);
1220 	sigaction(SIGCHLD, &sa, NULL);
1221 	sigaction(SIGINT, &sa, NULL);
1222 
1223 	setproctitle("(pf <spamd-white> update)");
1224 	greyscanner();
1225 	/* NOTREACHED */
1226 	exit(1);
1227 }
1228