xref: /netbsd-src/dist/pf/usr.sbin/authpf/authpf.c (revision de1dfb1250df962f1ff3a011772cf58e605aed11)
1 /*	$NetBSD: authpf.c,v 1.2 2004/06/25 00:06:09 itojun Exp $	*/
2 /*	$OpenBSD: authpf.c,v 1.75 2004/01/29 01:55:10 deraadt Exp $	*/
3 
4 /*
5  * Copyright (C) 1998 - 2002 Bob Beck (beck@openbsd.org).
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/types.h>
30 #include <sys/file.h>
31 #include <sys/ioctl.h>
32 #include <sys/socket.h>
33 #include <sys/time.h>
34 #include <sys/param.h>
35 
36 #include <net/if.h>
37 #include <netinet/in.h>
38 #include <net/pfvar.h>
39 #include <arpa/inet.h>
40 
41 #include <err.h>
42 #include <errno.h>
43 #include <pwd.h>
44 #include <signal.h>
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <string.h>
48 #include <syslog.h>
49 #include <unistd.h>
50 
51 #include <pfctl_parser.h>
52 #include <pfctl.h>
53 
54 #include "pathnames.h"
55 
56 extern int	symset(const char *, const char *, int);
57 
58 static int	read_config(FILE *);
59 static void	print_message(char *);
60 static int	allowed_luser(char *);
61 static int	check_luser(char *, char *);
62 static int	remove_stale_rulesets(void);
63 static int	change_filter(int, const char *, const char *);
64 static void	authpf_kill_states(void);
65 
66 int	dev;			/* pf device */
67 char	anchorname[PF_ANCHOR_NAME_SIZE] = "authpf";
68 char	rulesetname[PF_RULESET_NAME_SIZE];
69 
70 FILE	*pidfp;
71 char	*infile;		/* file name printed by yyerror() in parse.y */
72 char	 luser[MAXLOGNAME];	/* username */
73 char	 ipsrc[256];		/* ip as a string */
74 char	 pidfile[MAXPATHLEN];	/* we save pid in this file. */
75 
76 struct timeval	Tstart, Tend;	/* start and end times of session */
77 
78 volatile sig_atomic_t	want_death;
79 static void		need_death(int signo);
80 static __dead void	do_death(int);
81 
82 /*
83  * User shell for authenticating gateways. Sole purpose is to allow
84  * a user to ssh to a gateway, and have the gateway modify packet
85  * filters to allow access, then remove access when the user finishes
86  * up. Meant to be used only from ssh(1) connections.
87  */
88 int
89 main(int argc, char *argv[])
90 {
91 	int		 lockcnt = 0, n, pidfd;
92 	FILE		*config;
93 	struct in_addr	 ina;
94 	struct passwd	*pw;
95 	char		*cp;
96 	uid_t		 uid;
97 
98 	config = fopen(PATH_CONFFILE, "r");
99 
100 	if ((cp = getenv("SSH_TTY")) == NULL) {
101 		syslog(LOG_ERR, "non-interactive session connection for authpf");
102 		exit(1);
103 	}
104 
105 	if ((cp = getenv("SSH_CLIENT")) == NULL) {
106 		syslog(LOG_ERR, "cannot determine connection source");
107 		exit(1);
108 	}
109 
110 	if (strlcpy(ipsrc, cp, sizeof(ipsrc)) >= sizeof(ipsrc)) {
111 		syslog(LOG_ERR, "SSH_CLIENT variable too long");
112 		exit(1);
113 	}
114 	cp = strchr(ipsrc, ' ');
115 	if (!cp) {
116 		syslog(LOG_ERR, "corrupt SSH_CLIENT variable %s", ipsrc);
117 		exit(1);
118 	}
119 	*cp = '\0';
120 	if (inet_pton(AF_INET, ipsrc, &ina) != 1) {
121 		syslog(LOG_ERR,
122 		    "cannot determine IP from SSH_CLIENT %s", ipsrc);
123 		exit(1);
124 	}
125 	/* open the pf device */
126 	dev = open(PATH_DEVFILE, O_RDWR);
127 	if (dev == -1) {
128 		syslog(LOG_ERR, "cannot open packet filter device (%m)");
129 		goto die;
130 	}
131 
132 	uid = getuid();
133 	pw = getpwuid(uid);
134 	if (pw == NULL) {
135 		syslog(LOG_ERR, "cannot find user for uid %u", uid);
136 		goto die;
137 	}
138 	if (strcmp(pw->pw_shell, PATH_AUTHPF_SHELL)) {
139 		syslog(LOG_ERR, "wrong shell for user %s, uid %u",
140 		    pw->pw_name, pw->pw_uid);
141 		goto die;
142 	}
143 
144 	/*
145 	 * Paranoia, but this data _does_ come from outside authpf, and
146 	 * truncation would be bad.
147 	 */
148 	if (strlcpy(luser, pw->pw_name, sizeof(luser)) >= sizeof(luser)) {
149 		syslog(LOG_ERR, "username too long: %s", pw->pw_name);
150 		goto die;
151 	}
152 
153 	if ((n = snprintf(rulesetname, sizeof(rulesetname), "%s(%ld)",
154 	    luser, (long)getpid())) < 0 || n >= sizeof(rulesetname)) {
155 		syslog(LOG_INFO, "%s(%ld) too large, ruleset name will be %ld",
156 		    luser, (long)getpid(), (long)getpid());
157 		if ((n = snprintf(rulesetname, sizeof(rulesetname), "%ld",
158 		    (long)getpid())) < 0 || n >= sizeof(rulesetname)) {
159 			syslog(LOG_ERR, "pid too large for ruleset name");
160 			goto die;
161 		}
162 	}
163 
164 
165 	/* Make our entry in /var/authpf as /var/authpf/ipaddr */
166 	n = snprintf(pidfile, sizeof(pidfile), "%s/%s", PATH_PIDFILE, ipsrc);
167 	if (n < 0 || (u_int)n >= sizeof(pidfile)) {
168 		syslog(LOG_ERR, "path to pidfile too long");
169 		goto die;
170 	}
171 
172 	/*
173 	 * If someone else is already using this ip, then this person
174 	 * wants to switch users - so kill the old process and exit
175 	 * as well.
176 	 *
177 	 * Note, we could print a message and tell them to log out, but the
178 	 * usual case of this is that someone has left themselves logged in,
179 	 * with the authenticated connection iconized and someone else walks
180 	 * up to use and automatically logs in before using. If this just
181 	 * gets rid of the old one silently, the new user never knows they
182 	 * could have used someone else's old authentication. If we
183 	 * tell them to log out before switching users it is an invitation
184 	 * for abuse.
185 	 */
186 
187 	do {
188 		int	save_errno, otherpid = -1;
189 		char	otherluser[MAXLOGNAME];
190 
191 		if ((pidfd = open(pidfile, O_RDWR|O_CREAT, 0644)) == -1 ||
192 		    (pidfp = fdopen(pidfd, "r+")) == NULL) {
193 			if (pidfd != -1)
194 				close(pidfd);
195 			syslog(LOG_ERR, "cannot open or create %s: %s", pidfile,
196 			    strerror(errno));
197 			goto die;
198 		}
199 
200 		if (flock(fileno(pidfp), LOCK_EX|LOCK_NB) == 0)
201 			break;
202 		save_errno = errno;
203 
204 		/* Mark our pid, and username to our file. */
205 
206 		rewind(pidfp);
207 		/* 31 == MAXLOGNAME - 1 */
208 		if (fscanf(pidfp, "%d\n%31s\n", &otherpid, otherluser) != 2)
209 			otherpid = -1;
210 		syslog(LOG_DEBUG, "tried to lock %s, in use by pid %d: %s",
211 		    pidfile, otherpid, strerror(save_errno));
212 
213 		if (otherpid > 0) {
214 			syslog(LOG_INFO,
215 			    "killing prior auth (pid %d) of %s by user %s",
216 			    otherpid, ipsrc, otherluser);
217 			if (kill((pid_t) otherpid, SIGTERM) == -1) {
218 				syslog(LOG_INFO,
219 				    "could not kill process %d: (%m)",
220 				    otherpid);
221 			}
222 		}
223 
224 		/*
225 		 * we try to kill the previous process and acquire the lock
226 		 * for 10 seconds, trying once a second. if we can't after
227 		 * 10 attempts we log an error and give up
228 		 */
229 		if (++lockcnt > 10) {
230 			syslog(LOG_ERR, "cannot kill previous authpf (pid %d)",
231 			    otherpid);
232 			goto dogdeath;
233 		}
234 		sleep(1);
235 
236 		/* re-open, and try again. The previous authpf process
237 		 * we killed above should unlink the file and release
238 		 * it's lock, giving us a chance to get it now
239 		 */
240 		fclose(pidfp);
241 	} while (1);
242 
243 	/* revoke privs */
244 	seteuid(getuid());
245 	setuid(getuid());
246 
247 	openlog("authpf", LOG_PID | LOG_NDELAY, LOG_DAEMON);
248 
249 	if (!check_luser(PATH_BAN_DIR, luser) || !allowed_luser(luser)) {
250 		syslog(LOG_INFO, "user %s prohibited", luser);
251 		do_death(0);
252 	}
253 
254 	if (config == NULL || read_config(config)) {
255 		syslog(LOG_INFO, "bad or nonexistent %s", PATH_CONFFILE);
256 		do_death(0);
257 	}
258 
259 	if (remove_stale_rulesets()) {
260 		syslog(LOG_INFO, "error removing stale rulesets");
261 		do_death(0);
262 	}
263 
264 	/* We appear to be making headway, so actually mark our pid */
265 	rewind(pidfp);
266 	fprintf(pidfp, "%ld\n%s\n", (long)getpid(), luser);
267 	fflush(pidfp);
268 	(void) ftruncate(fileno(pidfp), ftell(pidfp));
269 
270 	if (change_filter(1, luser, ipsrc) == -1) {
271 		printf("Unable to modify filters\r\n");
272 		do_death(0);
273 	}
274 
275 	signal(SIGTERM, need_death);
276 	signal(SIGINT, need_death);
277 	signal(SIGALRM, need_death);
278 	signal(SIGPIPE, need_death);
279 	signal(SIGHUP, need_death);
280 	signal(SIGSTOP, need_death);
281 	signal(SIGTSTP, need_death);
282 	while (1) {
283 		printf("\r\nHello %s, ", luser);
284 		printf("You are authenticated from host \"%s\"\r\n", ipsrc);
285 		setproctitle("%s@%s", luser, ipsrc);
286 		print_message(PATH_MESSAGE);
287 		while (1) {
288 			sleep(10);
289 			if (want_death)
290 				do_death(1);
291 		}
292 	}
293 
294 	/* NOTREACHED */
295 dogdeath:
296 	printf("\r\n\r\nSorry, this service is currently unavailable due to ");
297 	printf("technical difficulties\r\n\r\n");
298 	print_message(PATH_PROBLEM);
299 	printf("\r\nYour authentication process (pid %ld) was unable to run\n",
300 	    (long)getpid());
301 	sleep(180); /* them lusers read reaaaaal slow */
302 die:
303 	do_death(0);
304 	return (0);
305 }
306 
307 /*
308  * reads config file in PATH_CONFFILE to set optional behaviours up
309  */
310 static int
311 read_config(FILE *f)
312 {
313 	char	buf[1024];
314 	int	i = 0;
315 
316 	do {
317 		char	**ap;
318 		char	 *pair[4], *cp, *tp;
319 		int	  len;
320 
321 		if (fgets(buf, sizeof(buf), f) == NULL) {
322 			fclose(f);
323 			return (0);
324 		}
325 		i++;
326 		len = strlen(buf);
327 		if (buf[len - 1] != '\n' && !feof(f)) {
328 			syslog(LOG_ERR, "line %d too long in %s", i,
329 			    PATH_CONFFILE);
330 			return (1);
331 		}
332 		buf[len - 1] = '\0';
333 
334 		for (cp = buf; *cp == ' ' || *cp == '\t'; cp++)
335 			; /* nothing */
336 
337 		if (!*cp || *cp == '#' || *cp == '\n')
338 			continue;
339 
340 		for (ap = pair; ap < &pair[3] &&
341 		    (*ap = strsep(&cp, "=")) != NULL; ) {
342 			if (**ap != '\0')
343 				ap++;
344 		}
345 		if (ap != &pair[2])
346 			goto parse_error;
347 
348 		tp = pair[1] + strlen(pair[1]);
349 		while ((*tp == ' ' || *tp == '\t') && tp >= pair[1])
350 			*tp-- = '\0';
351 
352 		if (strcasecmp(pair[0], "anchor") == 0) {
353 			if (!pair[1][0] || strlcpy(anchorname, pair[1],
354 			    sizeof(anchorname)) >= sizeof(anchorname))
355 				goto parse_error;
356 		}
357 	} while (!feof(f) && !ferror(f));
358 	fclose(f);
359 	return (0);
360 
361 parse_error:
362 	fclose(f);
363 	syslog(LOG_ERR, "parse error, line %d of %s", i, PATH_CONFFILE);
364 	return (1);
365 }
366 
367 
368 /*
369  * splatter a file to stdout - max line length of 1024,
370  * used for spitting message files at users to tell them
371  * they've been bad or we're unavailable.
372  */
373 static void
374 print_message(char *filename)
375 {
376 	char	 buf[1024];
377 	FILE	*f;
378 
379 	if ((f = fopen(filename, "r")) == NULL)
380 		return; /* fail silently, we don't care if it isn't there */
381 
382 	do {
383 		if (fgets(buf, sizeof(buf), f) == NULL) {
384 			fflush(stdout);
385 			fclose(f);
386 			return;
387 		}
388 	} while (fputs(buf, stdout) != EOF && !feof(f));
389 	fflush(stdout);
390 	fclose(f);
391 }
392 
393 /*
394  * allowed_luser checks to see if user "luser" is allowed to
395  * use this gateway by virtue of being listed in an allowed
396  * users file, namely /etc/authpf/authpf.allow .
397  *
398  * If /etc/authpf/authpf.allow does not exist, then we assume that
399  * all users who are allowed in by sshd(8) are permitted to
400  * use this gateway. If /etc/authpf/authpf.allow does exist, then a
401  * user must be listed if the connection is to continue, else
402  * the session terminates in the same manner as being banned.
403  */
404 static int
405 allowed_luser(char *luser)
406 {
407 	char	*buf, *lbuf;
408 	int	 matched;
409 	size_t	 len;
410 	FILE	*f;
411 
412 	if ((f = fopen(PATH_ALLOWFILE, "r")) == NULL) {
413 		if (errno == ENOENT) {
414 			/*
415 			 * allowfile doesn't exist, thus this gateway
416 			 * isn't restricted to certain users...
417 			 */
418 			return (1);
419 		}
420 
421 		/*
422 		 * luser may in fact be allowed, but we can't open
423 		 * the file even though it's there. probably a config
424 		 * problem.
425 		 */
426 		syslog(LOG_ERR, "cannot open allowed users file %s (%s)",
427 		    PATH_ALLOWFILE, strerror(errno));
428 		return (0);
429 	} else {
430 		/*
431 		 * /etc/authpf/authpf.allow exists, thus we do a linear
432 		 * search to see if they are allowed.
433 		 * also, if username "*" exists, then this is a
434 		 * "public" gateway, such as it is, so let
435 		 * everyone use it.
436 		 */
437 		lbuf = NULL;
438 		while ((buf = fgetln(f, &len))) {
439 			if (buf[len - 1] == '\n')
440 				buf[len - 1] = '\0';
441 			else {
442 				if ((lbuf = (char *)malloc(len + 1)) == NULL)
443 					err(1, NULL);
444 				memcpy(lbuf, buf, len);
445 				lbuf[len] = '\0';
446 				buf = lbuf;
447 			}
448 
449 			matched = strcmp(luser, buf) == 0 || strcmp("*", buf) == 0;
450 
451 			if (lbuf != NULL) {
452 				free(lbuf);
453 				lbuf = NULL;
454 			}
455 
456 			if (matched)
457 				return (1); /* matched an allowed username */
458 		}
459 		syslog(LOG_INFO, "denied access to %s: not listed in %s",
460 		    luser, PATH_ALLOWFILE);
461 
462 		/* reuse buf */
463 		buf = "\n\nSorry, you are not allowed to use this facility!\n";
464 		fputs(buf, stdout);
465 	}
466 	fflush(stdout);
467 	return (0);
468 }
469 
470 /*
471  * check_luser checks to see if user "luser" has been banned
472  * from using us by virtue of having an file of the same name
473  * in the "luserdir" directory.
474  *
475  * If the user has been banned, we copy the contents of the file
476  * to the user's screen. (useful for telling the user what to
477  * do to get un-banned, or just to tell them they aren't
478  * going to be un-banned.)
479  */
480 static int
481 check_luser(char *luserdir, char *luser)
482 {
483 	FILE	*f;
484 	int	 n;
485 	char	 tmp[MAXPATHLEN];
486 
487 	n = snprintf(tmp, sizeof(tmp), "%s/%s", luserdir, luser);
488 	if (n < 0 || (u_int)n >= sizeof(tmp)) {
489 		syslog(LOG_ERR, "provided banned directory line too long (%s)",
490 		    luserdir);
491 		return (0);
492 	}
493 	if ((f = fopen(tmp, "r")) == NULL) {
494 		if (errno == ENOENT) {
495 			/*
496 			 * file or dir doesn't exist, so therefore
497 			 * this luser isn't banned..  all is well
498 			 */
499 			return (1);
500 		} else {
501 			/*
502 			 * luser may in fact be banned, but we can't open the
503 			 * file even though it's there. probably a config
504 			 * problem.
505 			 */
506 			syslog(LOG_ERR, "cannot open banned file %s (%s)",
507 			    tmp, strerror(errno));
508 			return (0);
509 		}
510 	} else {
511 		/*
512 		 * luser is banned - spit the file at them to
513 		 * tell what they can do and where they can go.
514 		 */
515 		syslog(LOG_INFO, "denied access to %s: %s exists",
516 		    luser, tmp);
517 
518 		/* reuse tmp */
519 		strlcpy(tmp, "\n\n-**- Sorry, you have been banned! -**-\n\n",
520 		    sizeof(tmp));
521 		while (fputs(tmp, stdout) != EOF && !feof(f)) {
522 			if (fgets(tmp, sizeof(tmp), f) == NULL) {
523 				fflush(stdout);
524 				return (0);
525 			}
526 		}
527 	}
528 	fflush(stdout);
529 	return (0);
530 }
531 
532 /*
533  * Search for rulesets left by other authpf processes (either because they
534  * died ungracefully or were terminated) and remove them.
535  */
536 static int
537 remove_stale_rulesets(void)
538 {
539 	struct pfioc_ruleset	 prs;
540 	const int		 action[PF_RULESET_MAX] = { PF_SCRUB,
541 				    PF_PASS, PF_NAT, PF_BINAT, PF_RDR };
542 	u_int32_t		 nr, mnr;
543 
544 	memset(&prs, 0, sizeof(prs));
545 	strlcpy(prs.anchor, anchorname, sizeof(prs.anchor));
546 	if (ioctl(dev, DIOCGETRULESETS, &prs)) {
547 		if (errno == EINVAL)
548 			return (0);
549 		else
550 			return (1);
551 	}
552 
553 	mnr = prs.nr;
554 	nr = 0;
555 	while (nr < mnr) {
556 		char	*s, *t;
557 		pid_t	 pid;
558 
559 		prs.nr = nr;
560 		if (ioctl(dev, DIOCGETRULESET, &prs))
561 			return (1);
562 		errno = 0;
563 		if ((t = strchr(prs.name, '(')) == NULL)
564 			t = prs.name;
565 		else
566 			t++;
567 		pid = strtoul(t, &s, 10);
568 		if (!prs.name[0] || errno ||
569 		    (*s && (t == prs.name || *s != ')')))
570 			return (1);
571 		if (kill(pid, 0) && errno != EPERM) {
572 			int i;
573 
574 			for (i = 0; i < PF_RULESET_MAX; ++i) {
575 				struct pfioc_rule pr;
576 
577 				memset(&pr, 0, sizeof(pr));
578 				memcpy(pr.anchor, prs.anchor, sizeof(pr.anchor));
579 				memcpy(pr.ruleset, prs.name, sizeof(pr.ruleset));
580 				pr.rule.action = action[i];
581 				if ((ioctl(dev, DIOCBEGINRULES, &pr) ||
582 				    ioctl(dev, DIOCCOMMITRULES, &pr)) &&
583 				    errno != EINVAL)
584 					return (1);
585 			}
586 			mnr--;
587 		} else
588 			nr++;
589 	}
590 	return (0);
591 }
592 
593 /*
594  * Add/remove filter entries for user "luser" from ip "ipsrc"
595  */
596 static int
597 change_filter(int add, const char *luser, const char *ipsrc)
598 {
599 	char			 fn[MAXPATHLEN];
600 	FILE			*f = NULL;
601 	struct pfctl		 pf;
602 	struct pfr_buffer	 t;
603 	int			 i;
604 
605 	if (luser == NULL || !luser[0] || ipsrc == NULL || !ipsrc[0]) {
606 		syslog(LOG_ERR, "invalid luser/ipsrc");
607 		goto error;
608 	}
609 
610 	if (add) {
611 		if ((i = snprintf(fn, sizeof(fn), "%s/%s/authpf.rules",
612 		    PATH_USER_DIR, luser)) < 0 || i >= sizeof(fn)) {
613 			syslog(LOG_ERR, "user rule path too long");
614 			goto error;
615 		}
616 		if ((f = fopen(fn, "r")) == NULL && errno != ENOENT) {
617 			syslog(LOG_ERR, "cannot open %s (%m)", fn);
618 			goto error;
619 		}
620 		if (f == NULL) {
621 			if (strlcpy(fn, PATH_PFRULES, sizeof(fn)) >=
622 			    sizeof(fn)) {
623 				syslog(LOG_ERR, "rule path too long");
624 				goto error;
625 			}
626 			if ((f = fopen(fn, "r")) == NULL) {
627 				syslog(LOG_ERR, "cannot open %s (%m)", fn);
628 				goto error;
629 			}
630 		}
631 	}
632 
633 	if (pfctl_load_fingerprints(dev, 0)) {
634 		syslog(LOG_ERR, "unable to load kernel's OS fingerprints");
635 		goto error;
636 	}
637 	bzero(&t, sizeof(t));
638 	t.pfrb_type = PFRB_TRANS;
639 	memset(&pf, 0, sizeof(pf));
640 	for (i = 0; i < PF_RULESET_MAX; ++i) {
641 		if (pfctl_add_trans(&t, i, anchorname, rulesetname)) {
642 			syslog(LOG_ERR, "pfctl_add_trans %m");
643 			goto error;
644 		}
645 	}
646 	if (pfctl_trans(dev, &t, DIOCXBEGIN, 0)) {
647 		syslog(LOG_ERR, "DIOCXBEGIN (%s) %m", add?"add":"remove");
648 		goto error;
649 	}
650 
651 	if (add) {
652 		if (symset("user_ip", ipsrc, 0) ||
653 		    symset("user_id", luser, 0)) {
654 			syslog(LOG_ERR, "symset");
655 			goto error;
656 		}
657 
658 		pf.dev = dev;
659 		pf.trans = &t;
660 		pf.anchor = anchorname;
661 		pf.ruleset = rulesetname;
662 
663 		infile = fn;
664 		if (parse_rules(f, &pf) < 0) {
665 			syslog(LOG_ERR, "syntax error in rule file: "
666 			    "authpf rules not loaded");
667 			goto error;
668 		}
669 
670 		infile = NULL;
671 		fclose(f);
672 		f = NULL;
673 	}
674 
675 	if (pfctl_trans(dev, &t, DIOCXCOMMIT, 0)) {
676 		syslog(LOG_ERR, "DIOCXCOMMIT (%s) %m", add?"add":"remove");
677 		goto error;
678 	}
679 
680 	if (add) {
681 		gettimeofday(&Tstart, NULL);
682 		syslog(LOG_INFO, "allowing %s, user %s", ipsrc, luser);
683 	} else {
684 		gettimeofday(&Tend, NULL);
685 		syslog(LOG_INFO, "removed %s, user %s - duration %ld seconds",
686 		    ipsrc, luser, Tend.tv_sec - Tstart.tv_sec);
687 	}
688 	return (0);
689 
690 error:
691 	if (f != NULL)
692 		fclose(f);
693 	if (pfctl_trans(dev, &t, DIOCXROLLBACK, 0))
694 		syslog(LOG_ERR, "DIOCXROLLBACK (%s) %m", add?"add":"remove");
695 
696 	infile = NULL;
697 	return (-1);
698 }
699 
700 /*
701  * This is to kill off states that would otherwise be left behind stateful
702  * rules. This means we don't need to allow in more traffic than we really
703  * want to, since we don't have to worry about any luser sessions lasting
704  * longer than their ssh session. This function is based on
705  * pfctl_kill_states from pfctl.
706  */
707 static void
708 authpf_kill_states(void)
709 {
710 	struct pfioc_state_kill	psk;
711 	struct in_addr		target;
712 
713 	memset(&psk, 0, sizeof(psk));
714 	psk.psk_af = AF_INET;
715 
716 	inet_pton(AF_INET, ipsrc, &target);
717 
718 	/* Kill all states from ipsrc */
719 	psk.psk_src.addr.v.a.addr.v4 = target;
720 	memset(&psk.psk_src.addr.v.a.mask, 0xff,
721 	    sizeof(psk.psk_src.addr.v.a.mask));
722 	if (ioctl(dev, DIOCKILLSTATES, &psk))
723 		syslog(LOG_ERR, "DIOCKILLSTATES failed (%m)");
724 
725 	/* Kill all states to ipsrc */
726 	psk.psk_af = AF_INET;
727 	memset(&psk.psk_src, 0, sizeof(psk.psk_src));
728 	psk.psk_dst.addr.v.a.addr.v4 = target;
729 	memset(&psk.psk_dst.addr.v.a.mask, 0xff,
730 	    sizeof(psk.psk_dst.addr.v.a.mask));
731 	if (ioctl(dev, DIOCKILLSTATES, &psk))
732 		syslog(LOG_ERR, "DIOCKILLSTATES failed (%m)");
733 }
734 
735 /* signal handler that makes us go away properly */
736 static void
737 need_death(int signo)
738 {
739 	want_death = 1;
740 }
741 
742 /*
743  * function that removes our stuff when we go away.
744  */
745 static __dead void
746 do_death(int active)
747 {
748 	int	ret = 0;
749 
750 	if (active) {
751 		change_filter(0, luser, ipsrc);
752 		authpf_kill_states();
753 		remove_stale_rulesets();
754 	}
755 	if (pidfp)
756 		ftruncate(fileno(pidfp), 0);
757 	if (pidfile[0])
758 		if (unlink(pidfile) == -1)
759 			syslog(LOG_ERR, "cannot unlink %s (%m)", pidfile);
760 	exit(ret);
761 }
762 
763 /*
764  * callbacks for parse_rules(void)
765  */
766 
767 int
768 pfctl_add_rule(struct pfctl *pf, struct pf_rule *r)
769 {
770 	u_int8_t		rs_num;
771 	struct pfioc_rule	pr;
772 
773 	switch (r->action) {
774 	case PF_PASS:
775 	case PF_DROP:
776 		rs_num = PF_RULESET_FILTER;
777 		break;
778 	case PF_SCRUB:
779 		rs_num = PF_RULESET_SCRUB;
780 		break;
781 	case PF_NAT:
782 	case PF_NONAT:
783 		rs_num = PF_RULESET_NAT;
784 		break;
785 	case PF_RDR:
786 	case PF_NORDR:
787 		rs_num = PF_RULESET_RDR;
788 		break;
789 	case PF_BINAT:
790 	case PF_NOBINAT:
791 		rs_num = PF_RULESET_BINAT;
792 		break;
793 	default:
794 		syslog(LOG_ERR, "invalid rule action %d", r->action);
795 		return (1);
796 	}
797 
798 	bzero(&pr, sizeof(pr));
799 	strlcpy(pr.anchor, pf->anchor, sizeof(pr.anchor));
800 	strlcpy(pr.ruleset, pf->ruleset, sizeof(pr.ruleset));
801 	if (pfctl_add_pool(pf, &r->rpool, r->af))
802 		return (1);
803 	pr.ticket = pfctl_get_ticket(pf->trans, rs_num, pf->anchor,
804 	    pf->ruleset);
805 	pr.pool_ticket = pf->paddr.ticket;
806 	memcpy(&pr.rule, r, sizeof(pr.rule));
807 	if (ioctl(pf->dev, DIOCADDRULE, &pr)) {
808 		syslog(LOG_ERR, "DIOCADDRULE %m");
809 		return (1);
810 	}
811 	pfctl_clear_pool(&r->rpool);
812 	return (0);
813 }
814 
815 int
816 pfctl_add_pool(struct pfctl *pf, struct pf_pool *p, sa_family_t af)
817 {
818 	struct pf_pooladdr	*pa;
819 
820 	if (ioctl(pf->dev, DIOCBEGINADDRS, &pf->paddr)) {
821 		syslog(LOG_ERR, "DIOCBEGINADDRS %m");
822 		return (1);
823 	}
824 	pf->paddr.af = af;
825 	TAILQ_FOREACH(pa, &p->list, entries) {
826 		memcpy(&pf->paddr.addr, pa, sizeof(struct pf_pooladdr));
827 		if (ioctl(pf->dev, DIOCADDADDR, &pf->paddr)) {
828 			syslog(LOG_ERR, "DIOCADDADDR %m");
829 			return (1);
830 		}
831 	}
832 	return (0);
833 }
834 
835 void
836 pfctl_clear_pool(struct pf_pool *pool)
837 {
838 	struct pf_pooladdr	*pa;
839 
840 	while ((pa = TAILQ_FIRST(&pool->list)) != NULL) {
841 		TAILQ_REMOVE(&pool->list, pa, entries);
842 		free(pa);
843 	}
844 }
845 
846 int
847 pfctl_add_altq(struct pfctl *pf, struct pf_altq *a)
848 {
849 	fprintf(stderr, "altq rules not supported in authpf\n");
850 	return (1);
851 }
852 
853 int
854 pfctl_set_optimization(struct pfctl *pf, const char *opt)
855 {
856 	fprintf(stderr, "set optimization not supported in authpf\n");
857 	return (1);
858 }
859 
860 int
861 pfctl_set_logif(struct pfctl *pf, char *ifname)
862 {
863 	fprintf(stderr, "set loginterface not supported in authpf\n");
864 	return (1);
865 }
866 
867 int
868 pfctl_set_hostid(struct pfctl *pf, u_int32_t hostid)
869 {
870 	fprintf(stderr, "set hostid not supported in authpf\n");
871 	return (1);
872 }
873 
874 int
875 pfctl_set_timeout(struct pfctl *pf, const char *opt, int seconds, int quiet)
876 {
877 	fprintf(stderr, "set timeout not supported in authpf\n");
878 	return (1);
879 }
880 
881 int
882 pfctl_set_limit(struct pfctl *pf, const char *opt, unsigned int limit)
883 {
884 	fprintf(stderr, "set limit not supported in authpf\n");
885 	return (1);
886 }
887 
888 int
889 pfctl_set_debug(struct pfctl *pf, char *d)
890 {
891 	fprintf(stderr, "set debug not supported in authpf\n");
892 	return (1);
893 }
894 
895 int
896 pfctl_define_table(char *name, int flags, int addrs, const char *anchor,
897     const char *ruleset, struct pfr_buffer *ab, u_int32_t ticket)
898 {
899 	fprintf(stderr, "table definitions not yet supported in authpf\n");
900 	return (1);
901 }
902 
903 int
904 pfctl_rules(int dev, char *filename, int opts, char *anchorname,
905     char *rulesetname, struct pfr_buffer *t)
906 {
907 	/* never called, no anchors inside anchors, but we need the stub */
908 	fprintf(stderr, "load anchor not supported from authpf\n");
909 	return (1);
910 }
911 
912 void
913 pfctl_print_title(char *title)
914 {
915 }
916