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authpf.c revision 1.1
      1 /*	$OpenBSD: authpf.c,v 1.75 2004/01/29 01:55:10 deraadt Exp $	*/
      2 
      3 /*
      4  * Copyright (C) 1998 - 2002 Bob Beck (beck (at) openbsd.org).
      5  *
      6  * Redistribution and use in source and binary forms, with or without
      7  * modification, are permitted provided that the following conditions
      8  * are met:
      9  * 1. Redistributions of source code must retain the above copyright
     10  *    notice, this list of conditions and the following disclaimer.
     11  * 2. Redistributions in binary form must reproduce the above copyright
     12  *    notice, this list of conditions and the following disclaimer in the
     13  *    documentation and/or other materials provided with the distribution.
     14  *
     15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
     16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
     19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     25  * SUCH DAMAGE.
     26  */
     27 
     28 #include <sys/types.h>
     29 #include <sys/file.h>
     30 #include <sys/ioctl.h>
     31 #include <sys/socket.h>
     32 #include <sys/time.h>
     33 
     34 #include <net/if.h>
     35 #include <net/pfvar.h>
     36 #include <arpa/inet.h>
     37 
     38 #include <err.h>
     39 #include <errno.h>
     40 #include <pwd.h>
     41 #include <signal.h>
     42 #include <stdio.h>
     43 #include <stdlib.h>
     44 #include <string.h>
     45 #include <syslog.h>
     46 #include <unistd.h>
     47 
     48 #include <pfctl_parser.h>
     49 #include <pfctl.h>
     50 
     51 #include "pathnames.h"
     52 
     53 extern int	symset(const char *, const char *, int);
     54 
     55 static int	read_config(FILE *);
     56 static void	print_message(char *);
     57 static int	allowed_luser(char *);
     58 static int	check_luser(char *, char *);
     59 static int	remove_stale_rulesets(void);
     60 static int	change_filter(int, const char *, const char *);
     61 static void	authpf_kill_states(void);
     62 
     63 int	dev;			/* pf device */
     64 char	anchorname[PF_ANCHOR_NAME_SIZE] = "authpf";
     65 char	rulesetname[PF_RULESET_NAME_SIZE];
     66 
     67 FILE	*pidfp;
     68 char	*infile;		/* file name printed by yyerror() in parse.y */
     69 char	 luser[MAXLOGNAME];	/* username */
     70 char	 ipsrc[256];		/* ip as a string */
     71 char	 pidfile[MAXPATHLEN];	/* we save pid in this file. */
     72 
     73 struct timeval	Tstart, Tend;	/* start and end times of session */
     74 
     75 volatile sig_atomic_t	want_death;
     76 static void		need_death(int signo);
     77 static __dead void	do_death(int);
     78 
     79 /*
     80  * User shell for authenticating gateways. Sole purpose is to allow
     81  * a user to ssh to a gateway, and have the gateway modify packet
     82  * filters to allow access, then remove access when the user finishes
     83  * up. Meant to be used only from ssh(1) connections.
     84  */
     85 int
     86 main(int argc, char *argv[])
     87 {
     88 	int		 lockcnt = 0, n, pidfd;
     89 	FILE		*config;
     90 	struct in_addr	 ina;
     91 	struct passwd	*pw;
     92 	char		*cp;
     93 	uid_t		 uid;
     94 
     95 	config = fopen(PATH_CONFFILE, "r");
     96 
     97 	if ((cp = getenv("SSH_TTY")) == NULL) {
     98 		syslog(LOG_ERR, "non-interactive session connection for authpf");
     99 		exit(1);
    100 	}
    101 
    102 	if ((cp = getenv("SSH_CLIENT")) == NULL) {
    103 		syslog(LOG_ERR, "cannot determine connection source");
    104 		exit(1);
    105 	}
    106 
    107 	if (strlcpy(ipsrc, cp, sizeof(ipsrc)) >= sizeof(ipsrc)) {
    108 		syslog(LOG_ERR, "SSH_CLIENT variable too long");
    109 		exit(1);
    110 	}
    111 	cp = strchr(ipsrc, ' ');
    112 	if (!cp) {
    113 		syslog(LOG_ERR, "corrupt SSH_CLIENT variable %s", ipsrc);
    114 		exit(1);
    115 	}
    116 	*cp = '\0';
    117 	if (inet_pton(AF_INET, ipsrc, &ina) != 1) {
    118 		syslog(LOG_ERR,
    119 		    "cannot determine IP from SSH_CLIENT %s", ipsrc);
    120 		exit(1);
    121 	}
    122 	/* open the pf device */
    123 	dev = open(PATH_DEVFILE, O_RDWR);
    124 	if (dev == -1) {
    125 		syslog(LOG_ERR, "cannot open packet filter device (%m)");
    126 		goto die;
    127 	}
    128 
    129 	uid = getuid();
    130 	pw = getpwuid(uid);
    131 	if (pw == NULL) {
    132 		syslog(LOG_ERR, "cannot find user for uid %u", uid);
    133 		goto die;
    134 	}
    135 	if (strcmp(pw->pw_shell, PATH_AUTHPF_SHELL)) {
    136 		syslog(LOG_ERR, "wrong shell for user %s, uid %u",
    137 		    pw->pw_name, pw->pw_uid);
    138 		goto die;
    139 	}
    140 
    141 	/*
    142 	 * Paranoia, but this data _does_ come from outside authpf, and
    143 	 * truncation would be bad.
    144 	 */
    145 	if (strlcpy(luser, pw->pw_name, sizeof(luser)) >= sizeof(luser)) {
    146 		syslog(LOG_ERR, "username too long: %s", pw->pw_name);
    147 		goto die;
    148 	}
    149 
    150 	if ((n = snprintf(rulesetname, sizeof(rulesetname), "%s(%ld)",
    151 	    luser, (long)getpid())) < 0 || n >= sizeof(rulesetname)) {
    152 		syslog(LOG_INFO, "%s(%ld) too large, ruleset name will be %ld",
    153 		    luser, (long)getpid(), (long)getpid());
    154 		if ((n = snprintf(rulesetname, sizeof(rulesetname), "%ld",
    155 		    (long)getpid())) < 0 || n >= sizeof(rulesetname)) {
    156 			syslog(LOG_ERR, "pid too large for ruleset name");
    157 			goto die;
    158 		}
    159 	}
    160 
    161 
    162 	/* Make our entry in /var/authpf as /var/authpf/ipaddr */
    163 	n = snprintf(pidfile, sizeof(pidfile), "%s/%s", PATH_PIDFILE, ipsrc);
    164 	if (n < 0 || (u_int)n >= sizeof(pidfile)) {
    165 		syslog(LOG_ERR, "path to pidfile too long");
    166 		goto die;
    167 	}
    168 
    169 	/*
    170 	 * If someone else is already using this ip, then this person
    171 	 * wants to switch users - so kill the old process and exit
    172 	 * as well.
    173 	 *
    174 	 * Note, we could print a message and tell them to log out, but the
    175 	 * usual case of this is that someone has left themselves logged in,
    176 	 * with the authenticated connection iconized and someone else walks
    177 	 * up to use and automatically logs in before using. If this just
    178 	 * gets rid of the old one silently, the new user never knows they
    179 	 * could have used someone else's old authentication. If we
    180 	 * tell them to log out before switching users it is an invitation
    181 	 * for abuse.
    182 	 */
    183 
    184 	do {
    185 		int	save_errno, otherpid = -1;
    186 		char	otherluser[MAXLOGNAME];
    187 
    188 		if ((pidfd = open(pidfile, O_RDWR|O_CREAT, 0644)) == -1 ||
    189 		    (pidfp = fdopen(pidfd, "r+")) == NULL) {
    190 			if (pidfd != -1)
    191 				close(pidfd);
    192 			syslog(LOG_ERR, "cannot open or create %s: %s", pidfile,
    193 			    strerror(errno));
    194 			goto die;
    195 		}
    196 
    197 		if (flock(fileno(pidfp), LOCK_EX|LOCK_NB) == 0)
    198 			break;
    199 		save_errno = errno;
    200 
    201 		/* Mark our pid, and username to our file. */
    202 
    203 		rewind(pidfp);
    204 		/* 31 == MAXLOGNAME - 1 */
    205 		if (fscanf(pidfp, "%d\n%31s\n", &otherpid, otherluser) != 2)
    206 			otherpid = -1;
    207 		syslog(LOG_DEBUG, "tried to lock %s, in use by pid %d: %s",
    208 		    pidfile, otherpid, strerror(save_errno));
    209 
    210 		if (otherpid > 0) {
    211 			syslog(LOG_INFO,
    212 			    "killing prior auth (pid %d) of %s by user %s",
    213 			    otherpid, ipsrc, otherluser);
    214 			if (kill((pid_t) otherpid, SIGTERM) == -1) {
    215 				syslog(LOG_INFO,
    216 				    "could not kill process %d: (%m)",
    217 				    otherpid);
    218 			}
    219 		}
    220 
    221 		/*
    222 		 * we try to kill the previous process and acquire the lock
    223 		 * for 10 seconds, trying once a second. if we can't after
    224 		 * 10 attempts we log an error and give up
    225 		 */
    226 		if (++lockcnt > 10) {
    227 			syslog(LOG_ERR, "cannot kill previous authpf (pid %d)",
    228 			    otherpid);
    229 			goto dogdeath;
    230 		}
    231 		sleep(1);
    232 
    233 		/* re-open, and try again. The previous authpf process
    234 		 * we killed above should unlink the file and release
    235 		 * it's lock, giving us a chance to get it now
    236 		 */
    237 		fclose(pidfp);
    238 	} while (1);
    239 
    240 	/* revoke privs */
    241 	seteuid(getuid());
    242 	setuid(getuid());
    243 
    244 	openlog("authpf", LOG_PID | LOG_NDELAY, LOG_DAEMON);
    245 
    246 	if (!check_luser(PATH_BAN_DIR, luser) || !allowed_luser(luser)) {
    247 		syslog(LOG_INFO, "user %s prohibited", luser);
    248 		do_death(0);
    249 	}
    250 
    251 	if (config == NULL || read_config(config)) {
    252 		syslog(LOG_INFO, "bad or nonexistent %s", PATH_CONFFILE);
    253 		do_death(0);
    254 	}
    255 
    256 	if (remove_stale_rulesets()) {
    257 		syslog(LOG_INFO, "error removing stale rulesets");
    258 		do_death(0);
    259 	}
    260 
    261 	/* We appear to be making headway, so actually mark our pid */
    262 	rewind(pidfp);
    263 	fprintf(pidfp, "%ld\n%s\n", (long)getpid(), luser);
    264 	fflush(pidfp);
    265 	(void) ftruncate(fileno(pidfp), ftell(pidfp));
    266 
    267 	if (change_filter(1, luser, ipsrc) == -1) {
    268 		printf("Unable to modify filters\r\n");
    269 		do_death(0);
    270 	}
    271 
    272 	signal(SIGTERM, need_death);
    273 	signal(SIGINT, need_death);
    274 	signal(SIGALRM, need_death);
    275 	signal(SIGPIPE, need_death);
    276 	signal(SIGHUP, need_death);
    277 	signal(SIGSTOP, need_death);
    278 	signal(SIGTSTP, need_death);
    279 	while (1) {
    280 		printf("\r\nHello %s, ", luser);
    281 		printf("You are authenticated from host \"%s\"\r\n", ipsrc);
    282 		setproctitle("%s@%s", luser, ipsrc);
    283 		print_message(PATH_MESSAGE);
    284 		while (1) {
    285 			sleep(10);
    286 			if (want_death)
    287 				do_death(1);
    288 		}
    289 	}
    290 
    291 	/* NOTREACHED */
    292 dogdeath:
    293 	printf("\r\n\r\nSorry, this service is currently unavailable due to ");
    294 	printf("technical difficulties\r\n\r\n");
    295 	print_message(PATH_PROBLEM);
    296 	printf("\r\nYour authentication process (pid %ld) was unable to run\n",
    297 	    (long)getpid());
    298 	sleep(180); /* them lusers read reaaaaal slow */
    299 die:
    300 	do_death(0);
    301 }
    302 
    303 /*
    304  * reads config file in PATH_CONFFILE to set optional behaviours up
    305  */
    306 static int
    307 read_config(FILE *f)
    308 {
    309 	char	buf[1024];
    310 	int	i = 0;
    311 
    312 	do {
    313 		char	**ap;
    314 		char	 *pair[4], *cp, *tp;
    315 		int	  len;
    316 
    317 		if (fgets(buf, sizeof(buf), f) == NULL) {
    318 			fclose(f);
    319 			return (0);
    320 		}
    321 		i++;
    322 		len = strlen(buf);
    323 		if (buf[len - 1] != '\n' && !feof(f)) {
    324 			syslog(LOG_ERR, "line %d too long in %s", i,
    325 			    PATH_CONFFILE);
    326 			return (1);
    327 		}
    328 		buf[len - 1] = '\0';
    329 
    330 		for (cp = buf; *cp == ' ' || *cp == '\t'; cp++)
    331 			; /* nothing */
    332 
    333 		if (!*cp || *cp == '#' || *cp == '\n')
    334 			continue;
    335 
    336 		for (ap = pair; ap < &pair[3] &&
    337 		    (*ap = strsep(&cp, "=")) != NULL; ) {
    338 			if (**ap != '\0')
    339 				ap++;
    340 		}
    341 		if (ap != &pair[2])
    342 			goto parse_error;
    343 
    344 		tp = pair[1] + strlen(pair[1]);
    345 		while ((*tp == ' ' || *tp == '\t') && tp >= pair[1])
    346 			*tp-- = '\0';
    347 
    348 		if (strcasecmp(pair[0], "anchor") == 0) {
    349 			if (!pair[1][0] || strlcpy(anchorname, pair[1],
    350 			    sizeof(anchorname)) >= sizeof(anchorname))
    351 				goto parse_error;
    352 		}
    353 	} while (!feof(f) && !ferror(f));
    354 	fclose(f);
    355 	return (0);
    356 
    357 parse_error:
    358 	fclose(f);
    359 	syslog(LOG_ERR, "parse error, line %d of %s", i, PATH_CONFFILE);
    360 	return (1);
    361 }
    362 
    363 
    364 /*
    365  * splatter a file to stdout - max line length of 1024,
    366  * used for spitting message files at users to tell them
    367  * they've been bad or we're unavailable.
    368  */
    369 static void
    370 print_message(char *filename)
    371 {
    372 	char	 buf[1024];
    373 	FILE	*f;
    374 
    375 	if ((f = fopen(filename, "r")) == NULL)
    376 		return; /* fail silently, we don't care if it isn't there */
    377 
    378 	do {
    379 		if (fgets(buf, sizeof(buf), f) == NULL) {
    380 			fflush(stdout);
    381 			fclose(f);
    382 			return;
    383 		}
    384 	} while (fputs(buf, stdout) != EOF && !feof(f));
    385 	fflush(stdout);
    386 	fclose(f);
    387 }
    388 
    389 /*
    390  * allowed_luser checks to see if user "luser" is allowed to
    391  * use this gateway by virtue of being listed in an allowed
    392  * users file, namely /etc/authpf/authpf.allow .
    393  *
    394  * If /etc/authpf/authpf.allow does not exist, then we assume that
    395  * all users who are allowed in by sshd(8) are permitted to
    396  * use this gateway. If /etc/authpf/authpf.allow does exist, then a
    397  * user must be listed if the connection is to continue, else
    398  * the session terminates in the same manner as being banned.
    399  */
    400 static int
    401 allowed_luser(char *luser)
    402 {
    403 	char	*buf, *lbuf;
    404 	int	 matched;
    405 	size_t	 len;
    406 	FILE	*f;
    407 
    408 	if ((f = fopen(PATH_ALLOWFILE, "r")) == NULL) {
    409 		if (errno == ENOENT) {
    410 			/*
    411 			 * allowfile doesn't exist, thus this gateway
    412 			 * isn't restricted to certain users...
    413 			 */
    414 			return (1);
    415 		}
    416 
    417 		/*
    418 		 * luser may in fact be allowed, but we can't open
    419 		 * the file even though it's there. probably a config
    420 		 * problem.
    421 		 */
    422 		syslog(LOG_ERR, "cannot open allowed users file %s (%s)",
    423 		    PATH_ALLOWFILE, strerror(errno));
    424 		return (0);
    425 	} else {
    426 		/*
    427 		 * /etc/authpf/authpf.allow exists, thus we do a linear
    428 		 * search to see if they are allowed.
    429 		 * also, if username "*" exists, then this is a
    430 		 * "public" gateway, such as it is, so let
    431 		 * everyone use it.
    432 		 */
    433 		lbuf = NULL;
    434 		while ((buf = fgetln(f, &len))) {
    435 			if (buf[len - 1] == '\n')
    436 				buf[len - 1] = '\0';
    437 			else {
    438 				if ((lbuf = (char *)malloc(len + 1)) == NULL)
    439 					err(1, NULL);
    440 				memcpy(lbuf, buf, len);
    441 				lbuf[len] = '\0';
    442 				buf = lbuf;
    443 			}
    444 
    445 			matched = strcmp(luser, buf) == 0 || strcmp("*", buf) == 0;
    446 
    447 			if (lbuf != NULL) {
    448 				free(lbuf);
    449 				lbuf = NULL;
    450 			}
    451 
    452 			if (matched)
    453 				return (1); /* matched an allowed username */
    454 		}
    455 		syslog(LOG_INFO, "denied access to %s: not listed in %s",
    456 		    luser, PATH_ALLOWFILE);
    457 
    458 		/* reuse buf */
    459 		buf = "\n\nSorry, you are not allowed to use this facility!\n";
    460 		fputs(buf, stdout);
    461 	}
    462 	fflush(stdout);
    463 	return (0);
    464 }
    465 
    466 /*
    467  * check_luser checks to see if user "luser" has been banned
    468  * from using us by virtue of having an file of the same name
    469  * in the "luserdir" directory.
    470  *
    471  * If the user has been banned, we copy the contents of the file
    472  * to the user's screen. (useful for telling the user what to
    473  * do to get un-banned, or just to tell them they aren't
    474  * going to be un-banned.)
    475  */
    476 static int
    477 check_luser(char *luserdir, char *luser)
    478 {
    479 	FILE	*f;
    480 	int	 n;
    481 	char	 tmp[MAXPATHLEN];
    482 
    483 	n = snprintf(tmp, sizeof(tmp), "%s/%s", luserdir, luser);
    484 	if (n < 0 || (u_int)n >= sizeof(tmp)) {
    485 		syslog(LOG_ERR, "provided banned directory line too long (%s)",
    486 		    luserdir);
    487 		return (0);
    488 	}
    489 	if ((f = fopen(tmp, "r")) == NULL) {
    490 		if (errno == ENOENT) {
    491 			/*
    492 			 * file or dir doesn't exist, so therefore
    493 			 * this luser isn't banned..  all is well
    494 			 */
    495 			return (1);
    496 		} else {
    497 			/*
    498 			 * luser may in fact be banned, but we can't open the
    499 			 * file even though it's there. probably a config
    500 			 * problem.
    501 			 */
    502 			syslog(LOG_ERR, "cannot open banned file %s (%s)",
    503 			    tmp, strerror(errno));
    504 			return (0);
    505 		}
    506 	} else {
    507 		/*
    508 		 * luser is banned - spit the file at them to
    509 		 * tell what they can do and where they can go.
    510 		 */
    511 		syslog(LOG_INFO, "denied access to %s: %s exists",
    512 		    luser, tmp);
    513 
    514 		/* reuse tmp */
    515 		strlcpy(tmp, "\n\n-**- Sorry, you have been banned! -**-\n\n",
    516 		    sizeof(tmp));
    517 		while (fputs(tmp, stdout) != EOF && !feof(f)) {
    518 			if (fgets(tmp, sizeof(tmp), f) == NULL) {
    519 				fflush(stdout);
    520 				return (0);
    521 			}
    522 		}
    523 	}
    524 	fflush(stdout);
    525 	return (0);
    526 }
    527 
    528 /*
    529  * Search for rulesets left by other authpf processes (either because they
    530  * died ungracefully or were terminated) and remove them.
    531  */
    532 static int
    533 remove_stale_rulesets(void)
    534 {
    535 	struct pfioc_ruleset	 prs;
    536 	const int		 action[PF_RULESET_MAX] = { PF_SCRUB,
    537 				    PF_PASS, PF_NAT, PF_BINAT, PF_RDR };
    538 	u_int32_t		 nr, mnr;
    539 
    540 	memset(&prs, 0, sizeof(prs));
    541 	strlcpy(prs.anchor, anchorname, sizeof(prs.anchor));
    542 	if (ioctl(dev, DIOCGETRULESETS, &prs)) {
    543 		if (errno == EINVAL)
    544 			return (0);
    545 		else
    546 			return (1);
    547 	}
    548 
    549 	mnr = prs.nr;
    550 	nr = 0;
    551 	while (nr < mnr) {
    552 		char	*s, *t;
    553 		pid_t	 pid;
    554 
    555 		prs.nr = nr;
    556 		if (ioctl(dev, DIOCGETRULESET, &prs))
    557 			return (1);
    558 		errno = 0;
    559 		if ((t = strchr(prs.name, '(')) == NULL)
    560 			t = prs.name;
    561 		else
    562 			t++;
    563 		pid = strtoul(t, &s, 10);
    564 		if (!prs.name[0] || errno ||
    565 		    (*s && (t == prs.name || *s != ')')))
    566 			return (1);
    567 		if (kill(pid, 0) && errno != EPERM) {
    568 			int i;
    569 
    570 			for (i = 0; i < PF_RULESET_MAX; ++i) {
    571 				struct pfioc_rule pr;
    572 
    573 				memset(&pr, 0, sizeof(pr));
    574 				memcpy(pr.anchor, prs.anchor, sizeof(pr.anchor));
    575 				memcpy(pr.ruleset, prs.name, sizeof(pr.ruleset));
    576 				pr.rule.action = action[i];
    577 				if ((ioctl(dev, DIOCBEGINRULES, &pr) ||
    578 				    ioctl(dev, DIOCCOMMITRULES, &pr)) &&
    579 				    errno != EINVAL)
    580 					return (1);
    581 			}
    582 			mnr--;
    583 		} else
    584 			nr++;
    585 	}
    586 	return (0);
    587 }
    588 
    589 /*
    590  * Add/remove filter entries for user "luser" from ip "ipsrc"
    591  */
    592 static int
    593 change_filter(int add, const char *luser, const char *ipsrc)
    594 {
    595 	char			 fn[MAXPATHLEN];
    596 	FILE			*f = NULL;
    597 	struct pfctl		 pf;
    598 	struct pfr_buffer	 t;
    599 	int			 i;
    600 
    601 	if (luser == NULL || !luser[0] || ipsrc == NULL || !ipsrc[0]) {
    602 		syslog(LOG_ERR, "invalid luser/ipsrc");
    603 		goto error;
    604 	}
    605 
    606 	if (add) {
    607 		if ((i = snprintf(fn, sizeof(fn), "%s/%s/authpf.rules",
    608 		    PATH_USER_DIR, luser)) < 0 || i >= sizeof(fn)) {
    609 			syslog(LOG_ERR, "user rule path too long");
    610 			goto error;
    611 		}
    612 		if ((f = fopen(fn, "r")) == NULL && errno != ENOENT) {
    613 			syslog(LOG_ERR, "cannot open %s (%m)", fn);
    614 			goto error;
    615 		}
    616 		if (f == NULL) {
    617 			if (strlcpy(fn, PATH_PFRULES, sizeof(fn)) >=
    618 			    sizeof(fn)) {
    619 				syslog(LOG_ERR, "rule path too long");
    620 				goto error;
    621 			}
    622 			if ((f = fopen(fn, "r")) == NULL) {
    623 				syslog(LOG_ERR, "cannot open %s (%m)", fn);
    624 				goto error;
    625 			}
    626 		}
    627 	}
    628 
    629 	if (pfctl_load_fingerprints(dev, 0)) {
    630 		syslog(LOG_ERR, "unable to load kernel's OS fingerprints");
    631 		goto error;
    632 	}
    633 	bzero(&t, sizeof(t));
    634 	t.pfrb_type = PFRB_TRANS;
    635 	memset(&pf, 0, sizeof(pf));
    636 	for (i = 0; i < PF_RULESET_MAX; ++i) {
    637 		if (pfctl_add_trans(&t, i, anchorname, rulesetname)) {
    638 			syslog(LOG_ERR, "pfctl_add_trans %m");
    639 			goto error;
    640 		}
    641 	}
    642 	if (pfctl_trans(dev, &t, DIOCXBEGIN, 0)) {
    643 		syslog(LOG_ERR, "DIOCXBEGIN (%s) %m", add?"add":"remove");
    644 		goto error;
    645 	}
    646 
    647 	if (add) {
    648 		if (symset("user_ip", ipsrc, 0) ||
    649 		    symset("user_id", luser, 0)) {
    650 			syslog(LOG_ERR, "symset");
    651 			goto error;
    652 		}
    653 
    654 		pf.dev = dev;
    655 		pf.trans = &t;
    656 		pf.anchor = anchorname;
    657 		pf.ruleset = rulesetname;
    658 
    659 		infile = fn;
    660 		if (parse_rules(f, &pf) < 0) {
    661 			syslog(LOG_ERR, "syntax error in rule file: "
    662 			    "authpf rules not loaded");
    663 			goto error;
    664 		}
    665 
    666 		infile = NULL;
    667 		fclose(f);
    668 		f = NULL;
    669 	}
    670 
    671 	if (pfctl_trans(dev, &t, DIOCXCOMMIT, 0)) {
    672 		syslog(LOG_ERR, "DIOCXCOMMIT (%s) %m", add?"add":"remove");
    673 		goto error;
    674 	}
    675 
    676 	if (add) {
    677 		gettimeofday(&Tstart, NULL);
    678 		syslog(LOG_INFO, "allowing %s, user %s", ipsrc, luser);
    679 	} else {
    680 		gettimeofday(&Tend, NULL);
    681 		syslog(LOG_INFO, "removed %s, user %s - duration %ld seconds",
    682 		    ipsrc, luser, Tend.tv_sec - Tstart.tv_sec);
    683 	}
    684 	return (0);
    685 
    686 error:
    687 	if (f != NULL)
    688 		fclose(f);
    689 	if (pfctl_trans(dev, &t, DIOCXROLLBACK, 0))
    690 		syslog(LOG_ERR, "DIOCXROLLBACK (%s) %m", add?"add":"remove");
    691 
    692 	infile = NULL;
    693 	return (-1);
    694 }
    695 
    696 /*
    697  * This is to kill off states that would otherwise be left behind stateful
    698  * rules. This means we don't need to allow in more traffic than we really
    699  * want to, since we don't have to worry about any luser sessions lasting
    700  * longer than their ssh session. This function is based on
    701  * pfctl_kill_states from pfctl.
    702  */
    703 static void
    704 authpf_kill_states(void)
    705 {
    706 	struct pfioc_state_kill	psk;
    707 	struct in_addr		target;
    708 
    709 	memset(&psk, 0, sizeof(psk));
    710 	psk.psk_af = AF_INET;
    711 
    712 	inet_pton(AF_INET, ipsrc, &target);
    713 
    714 	/* Kill all states from ipsrc */
    715 	psk.psk_src.addr.v.a.addr.v4 = target;
    716 	memset(&psk.psk_src.addr.v.a.mask, 0xff,
    717 	    sizeof(psk.psk_src.addr.v.a.mask));
    718 	if (ioctl(dev, DIOCKILLSTATES, &psk))
    719 		syslog(LOG_ERR, "DIOCKILLSTATES failed (%m)");
    720 
    721 	/* Kill all states to ipsrc */
    722 	psk.psk_af = AF_INET;
    723 	memset(&psk.psk_src, 0, sizeof(psk.psk_src));
    724 	psk.psk_dst.addr.v.a.addr.v4 = target;
    725 	memset(&psk.psk_dst.addr.v.a.mask, 0xff,
    726 	    sizeof(psk.psk_dst.addr.v.a.mask));
    727 	if (ioctl(dev, DIOCKILLSTATES, &psk))
    728 		syslog(LOG_ERR, "DIOCKILLSTATES failed (%m)");
    729 }
    730 
    731 /* signal handler that makes us go away properly */
    732 static void
    733 need_death(int signo)
    734 {
    735 	want_death = 1;
    736 }
    737 
    738 /*
    739  * function that removes our stuff when we go away.
    740  */
    741 static __dead void
    742 do_death(int active)
    743 {
    744 	int	ret = 0;
    745 
    746 	if (active) {
    747 		change_filter(0, luser, ipsrc);
    748 		authpf_kill_states();
    749 		remove_stale_rulesets();
    750 	}
    751 	if (pidfp)
    752 		ftruncate(fileno(pidfp), 0);
    753 	if (pidfile[0])
    754 		if (unlink(pidfile) == -1)
    755 			syslog(LOG_ERR, "cannot unlink %s (%m)", pidfile);
    756 	exit(ret);
    757 }
    758 
    759 /*
    760  * callbacks for parse_rules(void)
    761  */
    762 
    763 int
    764 pfctl_add_rule(struct pfctl *pf, struct pf_rule *r)
    765 {
    766 	u_int8_t		rs_num;
    767 	struct pfioc_rule	pr;
    768 
    769 	switch (r->action) {
    770 	case PF_PASS:
    771 	case PF_DROP:
    772 		rs_num = PF_RULESET_FILTER;
    773 		break;
    774 	case PF_SCRUB:
    775 		rs_num = PF_RULESET_SCRUB;
    776 		break;
    777 	case PF_NAT:
    778 	case PF_NONAT:
    779 		rs_num = PF_RULESET_NAT;
    780 		break;
    781 	case PF_RDR:
    782 	case PF_NORDR:
    783 		rs_num = PF_RULESET_RDR;
    784 		break;
    785 	case PF_BINAT:
    786 	case PF_NOBINAT:
    787 		rs_num = PF_RULESET_BINAT;
    788 		break;
    789 	default:
    790 		syslog(LOG_ERR, "invalid rule action %d", r->action);
    791 		return (1);
    792 	}
    793 
    794 	bzero(&pr, sizeof(pr));
    795 	strlcpy(pr.anchor, pf->anchor, sizeof(pr.anchor));
    796 	strlcpy(pr.ruleset, pf->ruleset, sizeof(pr.ruleset));
    797 	if (pfctl_add_pool(pf, &r->rpool, r->af))
    798 		return (1);
    799 	pr.ticket = pfctl_get_ticket(pf->trans, rs_num, pf->anchor,
    800 	    pf->ruleset);
    801 	pr.pool_ticket = pf->paddr.ticket;
    802 	memcpy(&pr.rule, r, sizeof(pr.rule));
    803 	if (ioctl(pf->dev, DIOCADDRULE, &pr)) {
    804 		syslog(LOG_ERR, "DIOCADDRULE %m");
    805 		return (1);
    806 	}
    807 	pfctl_clear_pool(&r->rpool);
    808 	return (0);
    809 }
    810 
    811 int
    812 pfctl_add_pool(struct pfctl *pf, struct pf_pool *p, sa_family_t af)
    813 {
    814 	struct pf_pooladdr	*pa;
    815 
    816 	if (ioctl(pf->dev, DIOCBEGINADDRS, &pf->paddr)) {
    817 		syslog(LOG_ERR, "DIOCBEGINADDRS %m");
    818 		return (1);
    819 	}
    820 	pf->paddr.af = af;
    821 	TAILQ_FOREACH(pa, &p->list, entries) {
    822 		memcpy(&pf->paddr.addr, pa, sizeof(struct pf_pooladdr));
    823 		if (ioctl(pf->dev, DIOCADDADDR, &pf->paddr)) {
    824 			syslog(LOG_ERR, "DIOCADDADDR %m");
    825 			return (1);
    826 		}
    827 	}
    828 	return (0);
    829 }
    830 
    831 void
    832 pfctl_clear_pool(struct pf_pool *pool)
    833 {
    834 	struct pf_pooladdr	*pa;
    835 
    836 	while ((pa = TAILQ_FIRST(&pool->list)) != NULL) {
    837 		TAILQ_REMOVE(&pool->list, pa, entries);
    838 		free(pa);
    839 	}
    840 }
    841 
    842 int
    843 pfctl_add_altq(struct pfctl *pf, struct pf_altq *a)
    844 {
    845 	fprintf(stderr, "altq rules not supported in authpf\n");
    846 	return (1);
    847 }
    848 
    849 int
    850 pfctl_set_optimization(struct pfctl *pf, const char *opt)
    851 {
    852 	fprintf(stderr, "set optimization not supported in authpf\n");
    853 	return (1);
    854 }
    855 
    856 int
    857 pfctl_set_logif(struct pfctl *pf, char *ifname)
    858 {
    859 	fprintf(stderr, "set loginterface not supported in authpf\n");
    860 	return (1);
    861 }
    862 
    863 int
    864 pfctl_set_hostid(struct pfctl *pf, u_int32_t hostid)
    865 {
    866 	fprintf(stderr, "set hostid not supported in authpf\n");
    867 	return (1);
    868 }
    869 
    870 int
    871 pfctl_set_timeout(struct pfctl *pf, const char *opt, int seconds, int quiet)
    872 {
    873 	fprintf(stderr, "set timeout not supported in authpf\n");
    874 	return (1);
    875 }
    876 
    877 int
    878 pfctl_set_limit(struct pfctl *pf, const char *opt, unsigned int limit)
    879 {
    880 	fprintf(stderr, "set limit not supported in authpf\n");
    881 	return (1);
    882 }
    883 
    884 int
    885 pfctl_set_debug(struct pfctl *pf, char *d)
    886 {
    887 	fprintf(stderr, "set debug not supported in authpf\n");
    888 	return (1);
    889 }
    890 
    891 int
    892 pfctl_define_table(char *name, int flags, int addrs, const char *anchor,
    893     const char *ruleset, struct pfr_buffer *ab, u_int32_t ticket)
    894 {
    895 	fprintf(stderr, "table definitions not yet supported in authpf\n");
    896 	return (1);
    897 }
    898 
    899 int
    900 pfctl_rules(int dev, char *filename, int opts, char *anchorname,
    901     char *rulesetname, struct pfr_buffer *t)
    902 {
    903 	/* never called, no anchors inside anchors, but we need the stub */
    904 	fprintf(stderr, "load anchor not supported from authpf\n");
    905 	return (1);
    906 }
    907 
    908 void
    909 pfctl_print_title(char *title)
    910 {
    911 }
    912