1 /* $OpenBSD: authpf.c,v 1.104 2007/02/24 17:35:08 beck Exp $ */ 2 3 /* 4 * Copyright (C) 1998 - 2007 Bob Beck (beck@openbsd.org). 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/cdefs.h> 20 __FBSDID("$FreeBSD$"); 21 22 #include <sys/param.h> 23 #include <sys/file.h> 24 #include <sys/ioctl.h> 25 #include <sys/socket.h> 26 #include <sys/stat.h> 27 #include <sys/time.h> 28 #include <sys/wait.h> 29 30 #include <net/if.h> 31 #include <net/pfvar.h> 32 #include <arpa/inet.h> 33 34 #include <err.h> 35 #include <errno.h> 36 #ifdef __FreeBSD__ 37 #include <inttypes.h> 38 #endif 39 #include <login_cap.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 "pathnames.h" 49 50 static int read_config(FILE *); 51 static void print_message(char *); 52 static int allowed_luser(char *); 53 static int check_luser(char *, char *); 54 static int remove_stale_rulesets(void); 55 static int change_filter(int, const char *, const char *); 56 static int change_table(int, const char *); 57 static void authpf_kill_states(void); 58 59 int dev; /* pf device */ 60 char anchorname[PF_ANCHOR_NAME_SIZE] = "authpf"; 61 char rulesetname[MAXPATHLEN - PF_ANCHOR_NAME_SIZE - 2]; 62 char tablename[PF_TABLE_NAME_SIZE] = "authpf_users"; 63 64 FILE *pidfp; 65 char luser[MAXLOGNAME]; /* username */ 66 char ipsrc[256]; /* ip as a string */ 67 char pidfile[MAXPATHLEN]; /* we save pid in this file. */ 68 69 struct timeval Tstart, Tend; /* start and end times of session */ 70 71 volatile sig_atomic_t want_death; 72 static void need_death(int signo); 73 #ifdef __FreeBSD__ 74 static __dead2 void do_death(int); 75 #else 76 static __dead void do_death(int); 77 #endif 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 in6_addr ina; 91 struct passwd *pw; 92 char *cp; 93 gid_t gid; 94 uid_t uid; 95 char *shell; 96 login_cap_t *lc; 97 98 config = fopen(PATH_CONFFILE, "r"); 99 if (config == NULL) { 100 syslog(LOG_ERR, "can not open %s (%m)", PATH_CONFFILE); 101 exit(1); 102 } 103 104 if ((cp = getenv("SSH_TTY")) == NULL) { 105 syslog(LOG_ERR, "non-interactive session connection for authpf"); 106 exit(1); 107 } 108 109 if ((cp = getenv("SSH_CLIENT")) == NULL) { 110 syslog(LOG_ERR, "cannot determine connection source"); 111 exit(1); 112 } 113 114 if (strlcpy(ipsrc, cp, sizeof(ipsrc)) >= sizeof(ipsrc)) { 115 syslog(LOG_ERR, "SSH_CLIENT variable too long"); 116 exit(1); 117 } 118 cp = strchr(ipsrc, ' '); 119 if (!cp) { 120 syslog(LOG_ERR, "corrupt SSH_CLIENT variable %s", ipsrc); 121 exit(1); 122 } 123 *cp = '\0'; 124 if (inet_pton(AF_INET, ipsrc, &ina) != 1 && 125 inet_pton(AF_INET6, ipsrc, &ina) != 1) { 126 syslog(LOG_ERR, 127 "cannot determine IP from SSH_CLIENT %s", ipsrc); 128 exit(1); 129 } 130 /* open the pf device */ 131 dev = open(PATH_DEVFILE, O_RDWR); 132 if (dev == -1) { 133 syslog(LOG_ERR, "cannot open packet filter device (%m)"); 134 goto die; 135 } 136 137 uid = getuid(); 138 pw = getpwuid(uid); 139 if (pw == NULL) { 140 syslog(LOG_ERR, "cannot find user for uid %u", uid); 141 goto die; 142 } 143 144 if ((lc = login_getclass(pw->pw_class)) != NULL) 145 shell = (char *)login_getcapstr(lc, "shell", pw->pw_shell, 146 pw->pw_shell); 147 else 148 shell = pw->pw_shell; 149 150 login_close(lc); 151 152 if (strcmp(shell, PATH_AUTHPF_SHELL)) { 153 syslog(LOG_ERR, "wrong shell for user %s, uid %u", 154 pw->pw_name, pw->pw_uid); 155 if (shell != pw->pw_shell) 156 free(shell); 157 goto die; 158 } 159 160 if (shell != pw->pw_shell) 161 free(shell); 162 163 /* 164 * Paranoia, but this data _does_ come from outside authpf, and 165 * truncation would be bad. 166 */ 167 if (strlcpy(luser, pw->pw_name, sizeof(luser)) >= sizeof(luser)) { 168 syslog(LOG_ERR, "username too long: %s", pw->pw_name); 169 goto die; 170 } 171 172 if ((n = snprintf(rulesetname, sizeof(rulesetname), "%s(%ld)", 173 luser, (long)getpid())) < 0 || (u_int)n >= sizeof(rulesetname)) { 174 syslog(LOG_INFO, "%s(%ld) too large, ruleset name will be %ld", 175 luser, (long)getpid(), (long)getpid()); 176 if ((n = snprintf(rulesetname, sizeof(rulesetname), "%ld", 177 (long)getpid())) < 0 || (u_int)n >= sizeof(rulesetname)) { 178 syslog(LOG_ERR, "pid too large for ruleset name"); 179 goto die; 180 } 181 } 182 183 184 /* Make our entry in /var/authpf as /var/authpf/ipaddr */ 185 n = snprintf(pidfile, sizeof(pidfile), "%s/%s", PATH_PIDFILE, ipsrc); 186 if (n < 0 || (u_int)n >= sizeof(pidfile)) { 187 syslog(LOG_ERR, "path to pidfile too long"); 188 goto die; 189 } 190 191 /* 192 * If someone else is already using this ip, then this person 193 * wants to switch users - so kill the old process and exit 194 * as well. 195 * 196 * Note, we could print a message and tell them to log out, but the 197 * usual case of this is that someone has left themselves logged in, 198 * with the authenticated connection iconized and someone else walks 199 * up to use and automatically logs in before using. If this just 200 * gets rid of the old one silently, the new user never knows they 201 * could have used someone else's old authentication. If we 202 * tell them to log out before switching users it is an invitation 203 * for abuse. 204 */ 205 206 do { 207 int save_errno, otherpid = -1; 208 char otherluser[MAXLOGNAME]; 209 210 if ((pidfd = open(pidfile, O_RDWR|O_CREAT, 0644)) == -1 || 211 (pidfp = fdopen(pidfd, "r+")) == NULL) { 212 if (pidfd != -1) 213 close(pidfd); 214 syslog(LOG_ERR, "cannot open or create %s: %s", pidfile, 215 strerror(errno)); 216 goto die; 217 } 218 219 if (flock(fileno(pidfp), LOCK_EX|LOCK_NB) == 0) 220 break; 221 save_errno = errno; 222 223 /* Mark our pid, and username to our file. */ 224 225 rewind(pidfp); 226 /* 31 == MAXLOGNAME - 1 */ 227 if (fscanf(pidfp, "%d\n%31s\n", &otherpid, otherluser) != 2) 228 otherpid = -1; 229 syslog(LOG_DEBUG, "tried to lock %s, in use by pid %d: %s", 230 pidfile, otherpid, strerror(save_errno)); 231 232 if (otherpid > 0) { 233 syslog(LOG_INFO, 234 "killing prior auth (pid %d) of %s by user %s", 235 otherpid, ipsrc, otherluser); 236 if (kill((pid_t) otherpid, SIGTERM) == -1) { 237 syslog(LOG_INFO, 238 "could not kill process %d: (%m)", 239 otherpid); 240 } 241 } 242 243 /* 244 * we try to kill the previous process and acquire the lock 245 * for 10 seconds, trying once a second. if we can't after 246 * 10 attempts we log an error and give up 247 */ 248 if (++lockcnt > 10) { 249 syslog(LOG_ERR, "cannot kill previous authpf (pid %d)", 250 otherpid); 251 fclose(pidfp); 252 pidfp = NULL; 253 goto dogdeath; 254 } 255 sleep(1); 256 257 /* re-open, and try again. The previous authpf process 258 * we killed above should unlink the file and release 259 * it's lock, giving us a chance to get it now 260 */ 261 fclose(pidfp); 262 pidfp = NULL; 263 } while (1); 264 265 /* whack the group list */ 266 gid = getegid(); 267 if (setgroups(1, &gid) == -1) { 268 syslog(LOG_INFO, "setgroups: %s", strerror(errno)); 269 do_death(0); 270 } 271 272 /* revoke privs */ 273 uid = getuid(); 274 if (setresuid(uid, uid, uid) == -1) { 275 syslog(LOG_INFO, "setresuid: %s", strerror(errno)); 276 do_death(0); 277 } 278 openlog("authpf", LOG_PID | LOG_NDELAY, LOG_DAEMON); 279 280 if (!check_luser(PATH_BAN_DIR, luser) || !allowed_luser(luser)) { 281 syslog(LOG_INFO, "user %s prohibited", luser); 282 do_death(0); 283 } 284 285 if (read_config(config)) { 286 syslog(LOG_ERR, "invalid config file %s", PATH_CONFFILE); 287 do_death(0); 288 } 289 290 if (remove_stale_rulesets()) { 291 syslog(LOG_INFO, "error removing stale rulesets"); 292 do_death(0); 293 } 294 295 /* We appear to be making headway, so actually mark our pid */ 296 rewind(pidfp); 297 fprintf(pidfp, "%ld\n%s\n", (long)getpid(), luser); 298 fflush(pidfp); 299 (void) ftruncate(fileno(pidfp), ftello(pidfp)); 300 301 if (change_filter(1, luser, ipsrc) == -1) { 302 printf("Unable to modify filters\r\n"); 303 do_death(0); 304 } 305 if (change_table(1, ipsrc) == -1) { 306 printf("Unable to modify table\r\n"); 307 change_filter(0, luser, ipsrc); 308 do_death(0); 309 } 310 311 signal(SIGTERM, need_death); 312 signal(SIGINT, need_death); 313 signal(SIGALRM, need_death); 314 signal(SIGPIPE, need_death); 315 signal(SIGHUP, need_death); 316 signal(SIGQUIT, need_death); 317 signal(SIGTSTP, need_death); 318 while (1) { 319 printf("\r\nHello %s. ", luser); 320 printf("You are authenticated from host \"%s\"\r\n", ipsrc); 321 setproctitle("%s@%s", luser, ipsrc); 322 print_message(PATH_MESSAGE); 323 while (1) { 324 sleep(10); 325 if (want_death) 326 do_death(1); 327 } 328 } 329 330 /* NOTREACHED */ 331 dogdeath: 332 printf("\r\n\r\nSorry, this service is currently unavailable due to "); 333 printf("technical difficulties\r\n\r\n"); 334 print_message(PATH_PROBLEM); 335 printf("\r\nYour authentication process (pid %ld) was unable to run\n", 336 (long)getpid()); 337 sleep(180); /* them lusers read reaaaaal slow */ 338 die: 339 do_death(0); 340 341 /* NOTREACHED */ 342 } 343 344 /* 345 * reads config file in PATH_CONFFILE to set optional behaviours up 346 */ 347 static int 348 read_config(FILE *f) 349 { 350 char buf[1024]; 351 int i = 0; 352 353 do { 354 char **ap; 355 char *pair[4], *cp, *tp; 356 int len; 357 358 if (fgets(buf, sizeof(buf), f) == NULL) { 359 fclose(f); 360 return (0); 361 } 362 i++; 363 len = strlen(buf); 364 if (buf[len - 1] != '\n' && !feof(f)) { 365 syslog(LOG_ERR, "line %d too long in %s", i, 366 PATH_CONFFILE); 367 return (1); 368 } 369 buf[len - 1] = '\0'; 370 371 for (cp = buf; *cp == ' ' || *cp == '\t'; cp++) 372 ; /* nothing */ 373 374 if (!*cp || *cp == '#' || *cp == '\n') 375 continue; 376 377 for (ap = pair; ap < &pair[3] && 378 (*ap = strsep(&cp, "=")) != NULL; ) { 379 if (**ap != '\0') 380 ap++; 381 } 382 if (ap != &pair[2]) 383 goto parse_error; 384 385 tp = pair[1] + strlen(pair[1]); 386 while ((*tp == ' ' || *tp == '\t') && tp >= pair[1]) 387 *tp-- = '\0'; 388 389 if (strcasecmp(pair[0], "anchor") == 0) { 390 if (!pair[1][0] || strlcpy(anchorname, pair[1], 391 sizeof(anchorname)) >= sizeof(anchorname)) 392 goto parse_error; 393 } 394 if (strcasecmp(pair[0], "table") == 0) { 395 if (!pair[1][0] || strlcpy(tablename, pair[1], 396 sizeof(tablename)) >= sizeof(tablename)) 397 goto parse_error; 398 } 399 } while (!feof(f) && !ferror(f)); 400 fclose(f); 401 return (0); 402 403 parse_error: 404 fclose(f); 405 syslog(LOG_ERR, "parse error, line %d of %s", i, PATH_CONFFILE); 406 return (1); 407 } 408 409 410 /* 411 * splatter a file to stdout - max line length of 1024, 412 * used for spitting message files at users to tell them 413 * they've been bad or we're unavailable. 414 */ 415 static void 416 print_message(char *filename) 417 { 418 char buf[1024]; 419 FILE *f; 420 421 if ((f = fopen(filename, "r")) == NULL) 422 return; /* fail silently, we don't care if it isn't there */ 423 424 do { 425 if (fgets(buf, sizeof(buf), f) == NULL) { 426 fflush(stdout); 427 fclose(f); 428 return; 429 } 430 } while (fputs(buf, stdout) != EOF && !feof(f)); 431 fflush(stdout); 432 fclose(f); 433 } 434 435 /* 436 * allowed_luser checks to see if user "luser" is allowed to 437 * use this gateway by virtue of being listed in an allowed 438 * users file, namely /etc/authpf/authpf.allow . 439 * 440 * If /etc/authpf/authpf.allow does not exist, then we assume that 441 * all users who are allowed in by sshd(8) are permitted to 442 * use this gateway. If /etc/authpf/authpf.allow does exist, then a 443 * user must be listed if the connection is to continue, else 444 * the session terminates in the same manner as being banned. 445 */ 446 static int 447 allowed_luser(char *luser) 448 { 449 char *buf, *lbuf; 450 int matched; 451 size_t len; 452 FILE *f; 453 454 if ((f = fopen(PATH_ALLOWFILE, "r")) == NULL) { 455 if (errno == ENOENT) { 456 /* 457 * allowfile doesn't exist, thus this gateway 458 * isn't restricted to certain users... 459 */ 460 return (1); 461 } 462 463 /* 464 * luser may in fact be allowed, but we can't open 465 * the file even though it's there. probably a config 466 * problem. 467 */ 468 syslog(LOG_ERR, "cannot open allowed users file %s (%s)", 469 PATH_ALLOWFILE, strerror(errno)); 470 return (0); 471 } else { 472 /* 473 * /etc/authpf/authpf.allow exists, thus we do a linear 474 * search to see if they are allowed. 475 * also, if username "*" exists, then this is a 476 * "public" gateway, such as it is, so let 477 * everyone use it. 478 */ 479 lbuf = NULL; 480 while ((buf = fgetln(f, &len))) { 481 if (buf[len - 1] == '\n') 482 buf[len - 1] = '\0'; 483 else { 484 if ((lbuf = (char *)malloc(len + 1)) == NULL) 485 err(1, NULL); 486 memcpy(lbuf, buf, len); 487 lbuf[len] = '\0'; 488 buf = lbuf; 489 } 490 491 matched = strcmp(luser, buf) == 0 || strcmp("*", buf) == 0; 492 493 if (lbuf != NULL) { 494 free(lbuf); 495 lbuf = NULL; 496 } 497 498 if (matched) 499 return (1); /* matched an allowed username */ 500 } 501 syslog(LOG_INFO, "denied access to %s: not listed in %s", 502 luser, PATH_ALLOWFILE); 503 504 /* reuse buf */ 505 buf = "\n\nSorry, you are not allowed to use this facility!\n"; 506 fputs(buf, stdout); 507 } 508 fflush(stdout); 509 return (0); 510 } 511 512 /* 513 * check_luser checks to see if user "luser" has been banned 514 * from using us by virtue of having an file of the same name 515 * in the "luserdir" directory. 516 * 517 * If the user has been banned, we copy the contents of the file 518 * to the user's screen. (useful for telling the user what to 519 * do to get un-banned, or just to tell them they aren't 520 * going to be un-banned.) 521 */ 522 static int 523 check_luser(char *luserdir, char *luser) 524 { 525 FILE *f; 526 int n; 527 char tmp[MAXPATHLEN]; 528 529 n = snprintf(tmp, sizeof(tmp), "%s/%s", luserdir, luser); 530 if (n < 0 || (u_int)n >= sizeof(tmp)) { 531 syslog(LOG_ERR, "provided banned directory line too long (%s)", 532 luserdir); 533 return (0); 534 } 535 if ((f = fopen(tmp, "r")) == NULL) { 536 if (errno == ENOENT) { 537 /* 538 * file or dir doesn't exist, so therefore 539 * this luser isn't banned.. all is well 540 */ 541 return (1); 542 } else { 543 /* 544 * luser may in fact be banned, but we can't open the 545 * file even though it's there. probably a config 546 * problem. 547 */ 548 syslog(LOG_ERR, "cannot open banned file %s (%s)", 549 tmp, strerror(errno)); 550 return (0); 551 } 552 } else { 553 /* 554 * luser is banned - spit the file at them to 555 * tell what they can do and where they can go. 556 */ 557 syslog(LOG_INFO, "denied access to %s: %s exists", 558 luser, tmp); 559 560 /* reuse tmp */ 561 strlcpy(tmp, "\n\n-**- Sorry, you have been banned! -**-\n\n", 562 sizeof(tmp)); 563 while (fputs(tmp, stdout) != EOF && !feof(f)) { 564 if (fgets(tmp, sizeof(tmp), f) == NULL) { 565 fflush(stdout); 566 fclose(f); 567 return (0); 568 } 569 } 570 fclose(f); 571 } 572 fflush(stdout); 573 return (0); 574 } 575 576 /* 577 * Search for rulesets left by other authpf processes (either because they 578 * died ungracefully or were terminated) and remove them. 579 */ 580 static int 581 remove_stale_rulesets(void) 582 { 583 struct pfioc_ruleset prs; 584 u_int32_t nr, mnr; 585 586 memset(&prs, 0, sizeof(prs)); 587 strlcpy(prs.path, anchorname, sizeof(prs.path)); 588 if (ioctl(dev, DIOCGETRULESETS, &prs)) { 589 if (errno == EINVAL) 590 return (0); 591 else 592 return (1); 593 } 594 595 mnr = prs.nr; 596 nr = 0; 597 while (nr < mnr) { 598 char *s, *t; 599 pid_t pid; 600 601 prs.nr = nr; 602 if (ioctl(dev, DIOCGETRULESET, &prs)) 603 return (1); 604 errno = 0; 605 if ((t = strchr(prs.name, '(')) == NULL) 606 t = prs.name; 607 else 608 t++; 609 pid = strtoul(t, &s, 10); 610 if (!prs.name[0] || errno || 611 (*s && (t == prs.name || *s != ')'))) 612 return (1); 613 if (kill(pid, 0) && errno != EPERM) { 614 int i; 615 struct pfioc_trans_e t_e[PF_RULESET_MAX+1]; 616 struct pfioc_trans t; 617 618 bzero(&t, sizeof(t)); 619 bzero(t_e, sizeof(t_e)); 620 t.size = PF_RULESET_MAX+1; 621 t.esize = sizeof(t_e[0]); 622 t.array = t_e; 623 for (i = 0; i < PF_RULESET_MAX+1; ++i) { 624 t_e[i].rs_num = i; 625 snprintf(t_e[i].anchor, sizeof(t_e[i].anchor), 626 "%s/%s", anchorname, prs.name); 627 } 628 t_e[PF_RULESET_MAX].rs_num = PF_RULESET_TABLE; 629 if ((ioctl(dev, DIOCXBEGIN, &t) || 630 ioctl(dev, DIOCXCOMMIT, &t)) && 631 errno != EINVAL) 632 return (1); 633 mnr--; 634 } else 635 nr++; 636 } 637 return (0); 638 } 639 640 /* 641 * Add/remove filter entries for user "luser" from ip "ipsrc" 642 */ 643 static int 644 change_filter(int add, const char *luser, const char *ipsrc) 645 { 646 char *pargv[13] = { 647 "pfctl", "-p", "/dev/pf", "-q", "-a", "anchor/ruleset", 648 "-D", "user_ip=X", "-D", "user_id=X", "-f", 649 "file", NULL 650 }; 651 char *fdpath = NULL, *userstr = NULL, *ipstr = NULL; 652 char *rsn = NULL, *fn = NULL; 653 pid_t pid; 654 gid_t gid; 655 int s; 656 657 if (luser == NULL || !luser[0] || ipsrc == NULL || !ipsrc[0]) { 658 syslog(LOG_ERR, "invalid luser/ipsrc"); 659 goto error; 660 } 661 662 if (asprintf(&rsn, "%s/%s", anchorname, rulesetname) == -1) 663 goto no_mem; 664 if (asprintf(&fdpath, "/dev/fd/%d", dev) == -1) 665 goto no_mem; 666 if (asprintf(&ipstr, "user_ip=%s", ipsrc) == -1) 667 goto no_mem; 668 if (asprintf(&userstr, "user_id=%s", luser) == -1) 669 goto no_mem; 670 671 if (add) { 672 struct stat sb; 673 674 if (asprintf(&fn, "%s/%s/authpf.rules", PATH_USER_DIR, luser) 675 == -1) 676 goto no_mem; 677 if (stat(fn, &sb) == -1) { 678 free(fn); 679 if ((fn = strdup(PATH_PFRULES)) == NULL) 680 goto no_mem; 681 } 682 } 683 pargv[2] = fdpath; 684 pargv[5] = rsn; 685 pargv[7] = userstr; 686 pargv[9] = ipstr; 687 if (!add) 688 pargv[11] = "/dev/null"; 689 else 690 pargv[11] = fn; 691 692 switch (pid = fork()) { 693 case -1: 694 syslog(LOG_ERR, "fork failed"); 695 goto error; 696 case 0: 697 /* revoke group privs before exec */ 698 gid = getgid(); 699 if (setregid(gid, gid) == -1) { 700 err(1, "setregid"); 701 } 702 execvp(PATH_PFCTL, pargv); 703 warn("exec of %s failed", PATH_PFCTL); 704 _exit(1); 705 } 706 707 /* parent */ 708 waitpid(pid, &s, 0); 709 if (s != 0) { 710 syslog(LOG_ERR, "pfctl exited abnormally"); 711 goto error; 712 } 713 714 if (add) { 715 gettimeofday(&Tstart, NULL); 716 syslog(LOG_INFO, "allowing %s, user %s", ipsrc, luser); 717 } else { 718 gettimeofday(&Tend, NULL); 719 #ifdef __FreeBSD__ 720 syslog(LOG_INFO, "removed %s, user %s - duration %jd seconds", 721 ipsrc, luser, (intmax_t)(Tend.tv_sec - Tstart.tv_sec)); 722 #else 723 syslog(LOG_INFO, "removed %s, user %s - duration %ld seconds", 724 ipsrc, luser, Tend.tv_sec - Tstart.tv_sec); 725 #endif 726 } 727 return (0); 728 no_mem: 729 syslog(LOG_ERR, "malloc failed"); 730 error: 731 free(fdpath); 732 free(rsn); 733 free(userstr); 734 free(ipstr); 735 free(fn); 736 return (-1); 737 } 738 739 /* 740 * Add/remove this IP from the "authpf_users" table. 741 */ 742 static int 743 change_table(int add, const char *ipsrc) 744 { 745 struct pfioc_table io; 746 struct pfr_addr addr; 747 748 bzero(&io, sizeof(io)); 749 strlcpy(io.pfrio_table.pfrt_name, tablename, 750 sizeof(io.pfrio_table.pfrt_name)); 751 io.pfrio_buffer = &addr; 752 io.pfrio_esize = sizeof(addr); 753 io.pfrio_size = 1; 754 755 bzero(&addr, sizeof(addr)); 756 if (ipsrc == NULL || !ipsrc[0]) 757 return (-1); 758 if (inet_pton(AF_INET, ipsrc, &addr.pfra_ip4addr) == 1) { 759 addr.pfra_af = AF_INET; 760 addr.pfra_net = 32; 761 } else if (inet_pton(AF_INET6, ipsrc, &addr.pfra_ip6addr) == 1) { 762 addr.pfra_af = AF_INET6; 763 addr.pfra_net = 128; 764 } else { 765 syslog(LOG_ERR, "invalid ipsrc"); 766 return (-1); 767 } 768 769 if (ioctl(dev, add ? DIOCRADDADDRS : DIOCRDELADDRS, &io) && 770 errno != ESRCH) { 771 syslog(LOG_ERR, "cannot %s %s from table %s: %s", 772 add ? "add" : "remove", ipsrc, tablename, 773 strerror(errno)); 774 return (-1); 775 } 776 return (0); 777 } 778 779 /* 780 * This is to kill off states that would otherwise be left behind stateful 781 * rules. This means we don't need to allow in more traffic than we really 782 * want to, since we don't have to worry about any luser sessions lasting 783 * longer than their ssh session. This function is based on 784 * pfctl_kill_states from pfctl. 785 */ 786 static void 787 authpf_kill_states(void) 788 { 789 struct pfioc_state_kill psk; 790 struct pf_addr target; 791 792 memset(&psk, 0, sizeof(psk)); 793 memset(&target, 0, sizeof(target)); 794 795 if (inet_pton(AF_INET, ipsrc, &target.v4) == 1) 796 psk.psk_af = AF_INET; 797 else if (inet_pton(AF_INET6, ipsrc, &target.v6) == 1) 798 psk.psk_af = AF_INET6; 799 else { 800 syslog(LOG_ERR, "inet_pton(%s) failed", ipsrc); 801 return; 802 } 803 804 /* Kill all states from ipsrc */ 805 memcpy(&psk.psk_src.addr.v.a.addr, &target, 806 sizeof(psk.psk_src.addr.v.a.addr)); 807 memset(&psk.psk_src.addr.v.a.mask, 0xff, 808 sizeof(psk.psk_src.addr.v.a.mask)); 809 if (ioctl(dev, DIOCKILLSTATES, &psk)) 810 syslog(LOG_ERR, "DIOCKILLSTATES failed (%m)"); 811 812 /* Kill all states to ipsrc */ 813 memset(&psk.psk_src, 0, sizeof(psk.psk_src)); 814 memcpy(&psk.psk_dst.addr.v.a.addr, &target, 815 sizeof(psk.psk_dst.addr.v.a.addr)); 816 memset(&psk.psk_dst.addr.v.a.mask, 0xff, 817 sizeof(psk.psk_dst.addr.v.a.mask)); 818 if (ioctl(dev, DIOCKILLSTATES, &psk)) 819 syslog(LOG_ERR, "DIOCKILLSTATES failed (%m)"); 820 } 821 822 /* signal handler that makes us go away properly */ 823 static void 824 need_death(int signo) 825 { 826 want_death = 1; 827 } 828 829 /* 830 * function that removes our stuff when we go away. 831 */ 832 #ifdef __FreeBSD__ 833 static __dead2 void 834 #else 835 static __dead void 836 #endif 837 do_death(int active) 838 { 839 int ret = 0; 840 841 if (active) { 842 change_filter(0, luser, ipsrc); 843 change_table(0, ipsrc); 844 authpf_kill_states(); 845 remove_stale_rulesets(); 846 } 847 if (pidfile[0] && (pidfp != NULL)) 848 if (unlink(pidfile) == -1) 849 syslog(LOG_ERR, "cannot unlink %s (%m)", pidfile); 850 exit(ret); 851 } 852