1 /* $OpenBSD: src/sbin/dhclient/dhclient.c,v 1.146 2012/07/09 16:21:21 krw Exp $ */ 2 3 /* 4 * Copyright 2004 Henning Brauer <henning@openbsd.org> 5 * Copyright (c) 1995, 1996, 1997, 1998, 1999 6 * The Internet Software Consortium. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. Neither the name of The Internet Software Consortium nor the names 18 * of its contributors may be used to endorse or promote products derived 19 * from this software without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE INTERNET SOFTWARE CONSORTIUM AND 22 * CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, 23 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 24 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 25 * DISCLAIMED. IN NO EVENT SHALL THE INTERNET SOFTWARE CONSORTIUM OR 26 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 27 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 28 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF 29 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 30 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 31 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 32 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * This software has been written for the Internet Software Consortium 36 * by Ted Lemon <mellon@fugue.com> in cooperation with Vixie 37 * Enterprises. To learn more about the Internet Software Consortium, 38 * see ``http://www.vix.com/isc''. To learn more about Vixie 39 * Enterprises, see ``http://www.vix.com''. 40 * 41 * This client was substantially modified and enhanced by Elliot Poger 42 * for use on Linux while he was working on the MosquitoNet project at 43 * Stanford. 44 * 45 * The current version owes much to Elliot's Linux enhancements, but 46 * was substantially reorganized and partially rewritten by Ted Lemon 47 * so as to use the same networking framework that the Internet Software 48 * Consortium DHCP server uses. Much system-specific configuration code 49 * was moved into a shell script so that as support for more operating 50 * systems is added, it will not be necessary to port and maintain 51 * system-specific configuration code to these operating systems - instead, 52 * the shell script can invoke the native tools to accomplish the same 53 * purpose. 54 */ 55 #include <sys/ioctl.h> 56 57 #include <ctype.h> 58 #include <poll.h> 59 #include <pwd.h> 60 #include <unistd.h> 61 62 #include "dhcpd.h" 63 #include "privsep.h" 64 65 #define CLIENT_PATH "PATH=/usr/bin:/usr/sbin:/bin:/sbin" 66 #define DEFAULT_LEASE_TIME 43200 /* 12 hours... */ 67 #define TIME_MAX 2147483647 68 #define POLL_FAILURES 10 69 #define POLL_FAILURE_WAIT 1 /* Back off multiplier (seconds) */ 70 71 time_t cur_time; 72 73 char *path_dhclient_conf = _PATH_DHCLIENT_CONF; 74 char *path_dhclient_db = NULL; 75 76 int log_perror = 1; 77 int privfd; 78 int nullfd = -1; 79 int no_daemon; 80 int unknown_ok = 1; 81 int routefd = -1; 82 83 struct iaddr iaddr_broadcast = { 4, { 255, 255, 255, 255 } }; 84 struct in_addr inaddr_any; 85 struct sockaddr_in sockaddr_broadcast; 86 87 struct interface_info *ifi; 88 struct client_state *client; 89 struct client_config *config; 90 91 int findproto(char *, int); 92 struct sockaddr *get_ifa(char *, int); 93 void usage(void); 94 int check_option(struct client_lease *l, int option); 95 int ipv4addrs(char * buf); 96 int res_hnok(const char *dn); 97 char *option_as_string(unsigned int code, unsigned char *data, int len); 98 int fork_privchld(int, int); 99 void get_ifname(char *, char *); 100 101 time_t scripttime; 102 static FILE *leaseFile; 103 104 int 105 findproto(char *cp, int n) 106 { 107 struct sockaddr *sa; 108 int i; 109 110 if (n == 0) 111 return -1; 112 for (i = 1; i; i <<= 1) { 113 if (i & n) { 114 sa = (struct sockaddr *)cp; 115 switch (i) { 116 case RTA_IFA: 117 case RTA_DST: 118 case RTA_GATEWAY: 119 case RTA_NETMASK: 120 if (sa->sa_family == AF_INET) 121 return AF_INET; 122 if (sa->sa_family == AF_INET6) 123 return AF_INET6; 124 break; 125 case RTA_IFP: 126 break; 127 } 128 RT_ADVANCE(cp, sa); 129 } 130 } 131 return (-1); 132 } 133 134 struct sockaddr * 135 get_ifa(char *cp, int n) 136 { 137 struct sockaddr *sa; 138 int i; 139 140 if (n == 0) 141 return (NULL); 142 for (i = 1; i; i <<= 1) 143 if (i & n) { 144 sa = (struct sockaddr *)cp; 145 if (i == RTA_IFA) 146 return (sa); 147 RT_ADVANCE(cp, sa); 148 } 149 150 return (NULL); 151 } 152 struct iaddr defaddr = { .len = 4 }; /* NULL is for silence warnings */ 153 154 void 155 routehandler(void) 156 { 157 int linkstat; 158 char msg[2048]; 159 struct rt_msghdr *rtm; 160 struct if_msghdr *ifm; 161 struct ifa_msghdr *ifam; 162 struct if_announcemsghdr *ifan; 163 struct client_lease *l; 164 time_t t = time(NULL); 165 struct sockaddr *sa; 166 struct iaddr a; 167 ssize_t n; 168 char *errmsg, buf[64]; 169 170 do { 171 n = read(routefd, &msg, sizeof(msg)); 172 } while (n == -1 && errno == EINTR); 173 174 rtm = (struct rt_msghdr *)msg; 175 if (n < sizeof(rtm->rtm_msglen) || n < rtm->rtm_msglen || 176 rtm->rtm_version != RTM_VERSION) 177 return; 178 179 switch (rtm->rtm_type) { 180 case RTM_NEWADDR: 181 ifam = (struct ifa_msghdr *)rtm; 182 if (ifam->ifam_index != ifi->index) 183 break; 184 if (findproto((char *)(ifam + 1), ifam->ifam_addrs) != AF_INET) 185 break; 186 sa = get_ifa((char *)(ifam + 1), ifam->ifam_addrs); 187 if (sa == NULL) { 188 errmsg = "sa == NULL"; 189 goto die; 190 } 191 192 if ((a.len = sizeof(struct in_addr)) > sizeof(a.iabuf)) 193 error("king bula sez: len mismatch"); 194 memcpy(a.iabuf, &((struct sockaddr_in *)sa)->sin_addr, a.len); 195 if (addr_eq(a, defaddr)) 196 break; 197 198 /* state_panic() can try unexpired existing leases */ 199 if (client->active && addr_eq(a, client->active->address)) 200 break; 201 for (l = client->leases; l != NULL; l = l->next) 202 if (addr_eq(a, l->address)) 203 break; 204 205 if (l != NULL) 206 /* new addr is the one we set */ 207 break; 208 snprintf(buf, sizeof(buf), "%s: %s", 209 "new address not one we set", piaddr(a)); 210 errmsg = buf; 211 goto die; 212 case RTM_DELADDR: 213 ifam = (struct ifa_msghdr *)rtm; 214 if (ifam->ifam_index != ifi->index) 215 break; 216 if (findproto((char *)(ifam + 1), ifam->ifam_addrs) != AF_INET) 217 break; 218 /* XXX check addrs like RTM_NEWADDR instead of this? */ 219 if (scripttime == 0 || t < scripttime + 10) 220 break; 221 errmsg = "interface address deleted"; 222 goto die; 223 case RTM_IFINFO: 224 ifm = (struct if_msghdr *)rtm; 225 if (ifm->ifm_index != ifi->index) 226 break; 227 if ((rtm->rtm_flags & RTF_UP) == 0) { 228 errmsg = "interface down"; 229 goto die; 230 } 231 232 linkstat = 233 LINK_STATE_IS_UP(ifm->ifm_data.ifi_link_state) ? 1 : 0; 234 if (linkstat != ifi->linkstat) { 235 #ifdef DEBUG 236 debug("link state %s -> %s", 237 ifi->linkstat ? "up" : "down", 238 linkstat ? "up" : "down"); 239 #endif 240 ifi->linkstat = interface_status(ifi->name); 241 if (ifi->linkstat) { 242 client->state = S_REBOOTING; 243 state_reboot(); 244 } 245 } 246 break; 247 case RTM_IFANNOUNCE: 248 ifan = (struct if_announcemsghdr *)rtm; 249 if (ifan->ifan_what == IFAN_DEPARTURE && 250 ifan->ifan_index == ifi->index) { 251 errmsg = "interface departure"; 252 goto die; 253 } 254 break; 255 default: 256 break; 257 } 258 return; 259 260 die: 261 script_init("FAIL"); 262 script_go(); 263 error("routehandler: %s", errmsg); 264 } 265 266 int 267 main(int argc, char *argv[]) 268 { 269 int ch, fd, quiet = 0, i = 0, pipe_fd[2]; 270 struct passwd *pw; 271 272 /* Initially, log errors to stderr as well as to syslogd. */ 273 openlog(getprogname(), LOG_PID | LOG_NDELAY, DHCPD_LOG_FACILITY); 274 setlogmask(LOG_UPTO(LOG_INFO)); 275 276 while ((ch = getopt(argc, argv, "c:dl:qu")) != -1) 277 switch (ch) { 278 case 'c': 279 path_dhclient_conf = optarg; 280 break; 281 case 'd': 282 no_daemon = 1; 283 break; 284 case 'l': 285 path_dhclient_db = optarg; 286 break; 287 case 'q': 288 quiet = 1; 289 break; 290 case 'u': 291 unknown_ok = 0; 292 break; 293 default: 294 usage(); 295 } 296 297 argc -= optind; 298 argv += optind; 299 300 if (argc != 1) 301 usage(); 302 303 ifi = calloc(1, sizeof(*ifi)); 304 if (ifi == NULL) 305 error("ifi calloc"); 306 client = calloc(1, sizeof(*client)); 307 if (client == NULL) 308 error("client calloc"); 309 config = calloc(1, sizeof(*config)); 310 if (config == NULL) 311 error("config calloc"); 312 313 get_ifname(ifi->name, argv[0]); 314 if (path_dhclient_db == NULL && asprintf(&path_dhclient_db, "%s.%s", 315 _PATH_DHCLIENT_DB, ifi->name) == -1) 316 error("asprintf"); 317 318 if (quiet) 319 log_perror = 0; 320 321 tzset(); 322 time(&cur_time); 323 324 memset(&sockaddr_broadcast, 0, sizeof(sockaddr_broadcast)); 325 sockaddr_broadcast.sin_family = AF_INET; 326 sockaddr_broadcast.sin_port = htons(REMOTE_PORT); 327 sockaddr_broadcast.sin_addr.s_addr = INADDR_BROADCAST; 328 sockaddr_broadcast.sin_len = sizeof(sockaddr_broadcast); 329 inaddr_any.s_addr = INADDR_ANY; 330 331 read_client_conf(); 332 333 if (interface_status(ifi->name) == 0) { 334 interface_link_forceup(ifi->name); 335 /* Give it up to 4 seconds of silent grace to find link */ 336 i = -4; 337 } else 338 i = 0; 339 340 while (!(ifi->linkstat = interface_status(ifi->name))) { 341 if (i == 0) 342 fprintf(stderr, "%s: no link ...", ifi->name); 343 else if (i > 0) 344 fprintf(stderr, "."); 345 fflush(stderr); 346 if (++i > config->link_timeout) { 347 fprintf(stderr, " sleeping\n"); 348 goto dispatch; 349 } 350 sleep(1); 351 } 352 if (i > 0) 353 fprintf(stderr, " got link\n"); 354 355 dispatch: 356 if ((nullfd = open(_PATH_DEVNULL, O_RDWR, 0)) == -1) 357 error("cannot open %s: %m", _PATH_DEVNULL); 358 359 if ((pw = getpwnam("_dhcp")) == NULL) 360 error("no such user: _dhcp"); 361 362 if (pipe(pipe_fd) == -1) 363 error("pipe"); 364 365 fork_privchld(pipe_fd[0], pipe_fd[1]); 366 367 close(pipe_fd[0]); 368 privfd = pipe_fd[1]; 369 370 if ((fd = open(path_dhclient_db, O_RDONLY|O_EXLOCK|O_CREAT, 0)) == -1) 371 error("can't open and lock %s: %m", path_dhclient_db); 372 read_client_leases(); 373 if ((leaseFile = fopen(path_dhclient_db, "w")) == NULL) 374 error("can't open %s: %m", path_dhclient_db); 375 rewrite_client_leases(); 376 close(fd); 377 378 if ((routefd = socket(PF_ROUTE, SOCK_RAW, 0)) == -1) 379 error("socket(PF_ROUTE, SOCK_RAW): %m"); 380 381 /* set up the interface */ 382 discover_interface(); 383 384 if (chroot(_PATH_VAREMPTY) == -1) 385 error("chroot"); 386 if (chdir("/") == -1) 387 error("chdir(\"/\")"); 388 389 if (setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) == -1) 390 error("setresgid"); 391 if (setgroups(1, &pw->pw_gid) == -1) 392 error("setgroups"); 393 if (setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid) == -1) 394 error("setresuid"); 395 396 endpwent(); 397 398 setproctitle("%s", ifi->name); 399 400 if (ifi->linkstat) { 401 client->state = S_REBOOTING; 402 state_reboot(); 403 } else 404 go_daemon(); 405 406 dispatch(); 407 408 /* not reached */ 409 return (0); 410 } 411 412 void 413 usage(void) 414 { 415 fprintf(stderr, "usage: %s [-dqu] [-c file] [-l file] interface\n", 416 getprogname()); 417 exit(1); 418 } 419 420 /* 421 * Individual States: 422 * 423 * Each routine is called from the dhclient_state_machine() in one of 424 * these conditions: 425 * -> entering INIT state 426 * -> recvpacket_flag == 0: timeout in this state 427 * -> otherwise: received a packet in this state 428 * 429 * Return conditions as handled by dhclient_state_machine(): 430 * Returns 1, sendpacket_flag = 1: send packet, reset timer. 431 * Returns 1, sendpacket_flag = 0: just reset the timer (wait for a milestone). 432 * Returns 0: finish the nap which was interrupted for no good reason. 433 * 434 * Several per-interface variables are used to keep track of the process: 435 * active_lease: the lease that is being used on the interface 436 * (null pointer if not configured yet). 437 * offered_leases: leases corresponding to DHCPOFFER messages that have 438 * been sent to us by DHCP servers. 439 * acked_leases: leases corresponding to DHCPACK messages that have been 440 * sent to us by DHCP servers. 441 * sendpacket: DHCP packet we're trying to send. 442 * destination: IP address to send sendpacket to 443 * In addition, there are several relevant per-lease variables. 444 * T1_expiry, T2_expiry, lease_expiry: lease milestones 445 * In the active lease, these control the process of renewing the lease; 446 * In leases on the acked_leases list, this simply determines when we 447 * can no longer legitimately use the lease. 448 */ 449 void 450 state_reboot(void) 451 { 452 /* Cancel all timeouts, since a link state change gets us here 453 and can happen anytime. */ 454 cancel_timeout(); 455 456 /* If we don't remember an active lease, go straight to INIT. */ 457 if (!client->active || client->active->is_bootp) { 458 client->state = S_INIT; 459 state_init(); 460 return; 461 } 462 463 /* make_request doesn't initialize xid because it normally comes 464 from the DHCPDISCOVER, but we haven't sent a DHCPDISCOVER, 465 so pick an xid now. */ 466 client->xid = arc4random(); 467 468 /* Make a DHCPREQUEST packet, and set appropriate per-interface 469 flags. */ 470 make_request(client->active); 471 client->destination = iaddr_broadcast; 472 client->first_sending = cur_time; 473 client->interval = 0; 474 475 /* Send out the first DHCPREQUEST packet. */ 476 send_request(); 477 } 478 479 /* 480 * Called when a lease has completely expired and we've 481 * been unable to renew it. 482 */ 483 void 484 state_init(void) 485 { 486 /* Make a DHCPDISCOVER packet, and set appropriate per-interface 487 flags. */ 488 make_discover(client->active); 489 client->xid = client->packet.xid; 490 client->destination = iaddr_broadcast; 491 client->state = S_SELECTING; 492 client->first_sending = cur_time; 493 client->interval = 0; 494 495 /* Add an immediate timeout to cause the first DHCPDISCOVER packet 496 to go out. */ 497 send_discover(); 498 } 499 500 /* 501 * state_selecting is called when one or more DHCPOFFER packets 502 * have been received and a configurable period of time has passed. 503 */ 504 void 505 state_selecting(void) 506 { 507 struct client_lease *lp, *next, *picked; 508 509 /* Cancel state_selecting and send_discover timeouts, since either 510 one could have got us here. */ 511 cancel_timeout(); 512 513 /* We have received one or more DHCPOFFER packets. Currently, 514 the only criterion by which we judge leases is whether or 515 not we get a response when we arp for them. */ 516 picked = NULL; 517 for (lp = client->offered_leases; lp; lp = next) { 518 next = lp->next; 519 520 if (!picked) { 521 picked = lp; 522 } else { 523 make_decline(lp); 524 send_decline(); 525 free_client_lease(lp); 526 } 527 } 528 client->offered_leases = NULL; 529 530 /* If we just tossed all the leases we were offered, go back 531 to square one. */ 532 if (!picked) { 533 client->state = S_INIT; 534 state_init(); 535 return; 536 } 537 picked->next = NULL; 538 539 /* If it was a BOOTREPLY, we can just take the address right now. */ 540 if (!picked->options[DHO_DHCP_MESSAGE_TYPE].len) { 541 client->new = picked; 542 543 /* Make up some lease expiry times 544 XXX these should be configurable. */ 545 client->new->expiry = cur_time + 12000; 546 client->new->renewal += cur_time + 8000; 547 client->new->rebind += cur_time + 10000; 548 549 client->state = S_REQUESTING; 550 551 /* Bind to the address we received. */ 552 bind_lease(); 553 return; 554 } 555 556 /* Go to the REQUESTING state. */ 557 client->destination = iaddr_broadcast; 558 client->state = S_REQUESTING; 559 client->first_sending = cur_time; 560 client->interval = 0; 561 562 /* Make a DHCPREQUEST packet from the lease we picked. */ 563 make_request(picked); 564 client->xid = client->packet.xid; 565 566 /* Toss the lease we picked - we'll get it back in a DHCPACK. */ 567 free_client_lease(picked); 568 569 /* Add an immediate timeout to send the first DHCPREQUEST packet. */ 570 send_request(); 571 } 572 573 void 574 dhcpack(struct iaddr client_addr, struct option_data *options) 575 { 576 struct client_lease *lease; 577 578 579 if (client->state != S_REBOOTING && 580 client->state != S_REQUESTING && 581 client->state != S_RENEWING && 582 client->state != S_REBINDING) 583 return; 584 585 586 lease = packet_to_lease(options); 587 if (!lease) { 588 note("packet_to_lease failed."); 589 return; 590 } 591 592 client->new = lease; 593 594 /* Stop resending DHCPREQUEST. */ 595 cancel_timeout(); 596 597 /* Figure out the lease time. */ 598 if (client->new->options[DHO_DHCP_LEASE_TIME].data) 599 client->new->expiry = 600 getULong(client->new->options[DHO_DHCP_LEASE_TIME].data); 601 else 602 client->new->expiry = DEFAULT_LEASE_TIME; 603 /* A number that looks negative here is really just very large, 604 because the lease expiry offset is unsigned. */ 605 if (client->new->expiry < 0) 606 client->new->expiry = TIME_MAX; 607 /* XXX should be fixed by resetting the client state */ 608 if (client->new->expiry < 60) 609 client->new->expiry = 60; 610 611 /* Take the server-provided renewal time if there is one; 612 otherwise figure it out according to the spec. */ 613 if (client->new->options[DHO_DHCP_RENEWAL_TIME].len) 614 client->new->renewal = 615 getULong(client->new->options[DHO_DHCP_RENEWAL_TIME].data); 616 else 617 client->new->renewal = client->new->expiry / 2; 618 619 /* Same deal with the rebind time. */ 620 if (client->new->options[DHO_DHCP_REBINDING_TIME].len) 621 client->new->rebind = 622 getULong(client->new->options[DHO_DHCP_REBINDING_TIME].data); 623 else 624 client->new->rebind = client->new->renewal + 625 client->new->renewal / 2 + client->new->renewal / 4; 626 627 client->new->expiry += cur_time; 628 /* Lease lengths can never be negative. */ 629 if (client->new->expiry < cur_time) 630 client->new->expiry = TIME_MAX; 631 client->new->renewal += cur_time; 632 if (client->new->renewal < cur_time) 633 client->new->renewal = TIME_MAX; 634 client->new->rebind += cur_time; 635 if (client->new->rebind < cur_time) 636 client->new->rebind = TIME_MAX; 637 638 bind_lease(); 639 } 640 641 void 642 bind_lease(void) 643 { 644 /* Run the client script with the new parameters. */ 645 script_init((client->state == S_REQUESTING ? "BOUND" : 646 (client->state == S_RENEWING ? "RENEW" : 647 (client->state == S_REBOOTING ? "REBOOT" : "REBIND")))); 648 if (client->active && client->state != S_REBOOTING) 649 script_write_params("old_", client->active); 650 script_write_params("new_", client->new); 651 script_go(); 652 653 /* Replace the old active lease with the new one. */ 654 if (client->active) 655 free_client_lease(client->active); 656 client->active = client->new; 657 client->new = NULL; 658 659 /* Write out new leases file. */ 660 rewrite_client_leases(); 661 662 /* Set timeout to start the renewal process. */ 663 set_timeout(client->active->renewal, state_bound); 664 665 note("bound to %s -- renewal in %ld seconds.", 666 piaddr(client->active->address), 667 client->active->renewal - cur_time); 668 client->state = S_BOUND; 669 reinitialize_interface(); 670 go_daemon(); 671 } 672 673 /* 674 * state_bound is called when we've successfully bound to a particular 675 * lease, but the renewal time on that lease has expired. We are 676 * expected to unicast a DHCPREQUEST to the server that gave us our 677 * original lease. 678 */ 679 void 680 state_bound(void) 681 { 682 /* T1 has expired. */ 683 make_request(client->active); 684 client->xid = client->packet.xid; 685 686 if (client->active->options[DHO_DHCP_SERVER_IDENTIFIER].len == 4) { 687 memcpy(client->destination.iabuf, 688 client->active->options[DHO_DHCP_SERVER_IDENTIFIER].data, 689 4); 690 client->destination.len = 4; 691 } else 692 client->destination = iaddr_broadcast; 693 694 client->first_sending = cur_time; 695 client->interval = 0; 696 client->state = S_RENEWING; 697 698 /* Send the first packet immediately. */ 699 send_request(); 700 } 701 702 void 703 dhcpoffer(struct iaddr client_addr, struct option_data *options) 704 { 705 struct client_lease *lease, *lp; 706 int i; 707 int stop_selecting; 708 char *name = options[DHO_DHCP_MESSAGE_TYPE].len ? "DHCPOFFER" : 709 "BOOTREPLY"; 710 711 712 if (client->state != S_SELECTING) 713 return; 714 715 716 /* If this lease doesn't supply the minimum required parameters, 717 blow it off. */ 718 for (i = 0; config->required_options[i]; i++) { 719 if (!options[config->required_options[i]].len) { 720 note("%s isn't satisfactory.", name); 721 return; 722 } 723 } 724 725 /* If we've already seen this lease, don't record it again. */ 726 for (lease = client->offered_leases; 727 lease; lease = lease->next) { 728 if (lease->address.len == sizeof(client->packet.yiaddr) && 729 !memcmp(lease->address.iabuf, 730 &client->packet.yiaddr, lease->address.len)) { 731 #ifdef DEBUG 732 debug("%s already seen.", name); 733 #endif 734 return; 735 } 736 } 737 738 lease = packet_to_lease(options); 739 if (!lease) { 740 note("packet_to_lease failed."); 741 return; 742 } 743 744 /* If this lease was acquired through a BOOTREPLY, record that 745 fact. */ 746 if (!options[DHO_DHCP_MESSAGE_TYPE].len) 747 lease->is_bootp = 1; 748 749 /* Figure out when we're supposed to stop selecting. */ 750 stop_selecting = client->first_sending + config->select_interval; 751 752 /* If this is the lease we asked for, put it at the head of the 753 list, and don't mess with the arp request timeout. */ 754 if (addr_eq(lease->address, client->requested_address)) { 755 lease->next = client->offered_leases; 756 client->offered_leases = lease; 757 } else { 758 /* Put the lease at the end of the list. */ 759 lease->next = NULL; 760 if (!client->offered_leases) 761 client->offered_leases = lease; 762 else { 763 for (lp = client->offered_leases; lp->next; 764 lp = lp->next) 765 ; /* nothing */ 766 lp->next = lease; 767 } 768 } 769 770 /* If the selecting interval has expired, go immediately to 771 state_selecting(). Otherwise, time out into 772 state_selecting at the select interval. */ 773 if (stop_selecting <= cur_time) 774 state_selecting(); 775 else { 776 set_timeout(stop_selecting, state_selecting); 777 } 778 } 779 780 /* 781 * Allocate a client_lease structure and initialize it from the 782 * parameters in the specified packet. 783 */ 784 struct client_lease * 785 packet_to_lease(struct option_data *options) 786 { 787 struct client_lease *lease; 788 int i; 789 790 lease = malloc(sizeof(struct client_lease)); 791 792 if (!lease) { 793 warning("dhcpoffer: no memory to record lease."); 794 return (NULL); 795 } 796 797 memset(lease, 0, sizeof(*lease)); 798 799 /* Copy the lease options. */ 800 for (i = 0; i < 256; i++) { 801 if (options[i].len) { 802 lease->options[i] = options[i]; 803 options[i].data = NULL; 804 options[i].len = 0; 805 if (!check_option(lease, i)) { 806 warning("Invalid lease option - ignoring offer"); 807 free_client_lease(lease); 808 return (NULL); 809 } 810 } 811 } 812 813 lease->address.len = sizeof(client->packet.yiaddr); 814 memcpy(lease->address.iabuf, &client->packet.yiaddr, 815 lease->address.len); 816 817 /* If the server name was filled out, copy it. */ 818 if ((!lease->options[DHO_DHCP_OPTION_OVERLOAD].len || 819 !(lease->options[DHO_DHCP_OPTION_OVERLOAD].data[0] & 2)) && 820 client->packet.sname[0]) { 821 lease->server_name = malloc(DHCP_SNAME_LEN + 1); 822 if (!lease->server_name) { 823 warning("dhcpoffer: no memory for server name."); 824 free_client_lease(lease); 825 return (NULL); 826 } 827 memcpy(lease->server_name, client->packet.sname, 828 DHCP_SNAME_LEN); 829 lease->server_name[DHCP_SNAME_LEN] = '\0'; 830 if (!res_hnok(lease->server_name)) { 831 warning("Bogus server name %s", lease->server_name); 832 free(lease->server_name); 833 lease->server_name = NULL; 834 } 835 } 836 837 /* Ditto for the filename. */ 838 if ((!lease->options[DHO_DHCP_OPTION_OVERLOAD].len || 839 !(lease->options[DHO_DHCP_OPTION_OVERLOAD].data[0] & 1)) && 840 client->packet.file[0]) { 841 /* Don't count on the NUL terminator. */ 842 lease->filename = malloc(DHCP_FILE_LEN + 1); 843 if (!lease->filename) { 844 warning("dhcpoffer: no memory for filename."); 845 free_client_lease(lease); 846 return (NULL); 847 } 848 memcpy(lease->filename, client->packet.file, DHCP_FILE_LEN); 849 lease->filename[DHCP_FILE_LEN] = '\0'; 850 } 851 return lease; 852 } 853 854 void 855 dhcpnak(struct iaddr client_addr, struct option_data *options) 856 { 857 858 if (client->state != S_REBOOTING && 859 client->state != S_REQUESTING && 860 client->state != S_RENEWING && 861 client->state != S_REBINDING) 862 return; 863 864 865 if (!client->active) { 866 note("DHCPNAK with no active lease."); 867 return; 868 } 869 870 free_client_lease(client->active); 871 client->active = NULL; 872 873 /* Stop sending DHCPREQUEST packets... */ 874 cancel_timeout(); 875 876 client->state = S_INIT; 877 state_init(); 878 } 879 880 /* 881 * Send out a DHCPDISCOVER packet, and set a timeout to send out another 882 * one after the right interval has expired. If we don't get an offer by 883 * the time we reach the panic interval, call the panic function. 884 */ 885 void 886 send_discover(void) 887 { 888 int interval, increase = 1; 889 890 /* Figure out how long it's been since we started transmitting. */ 891 interval = cur_time - client->first_sending; 892 893 /* If we're past the panic timeout, call the script and tell it 894 we haven't found anything for this interface yet. */ 895 if (interval > config->timeout) { 896 state_panic(); 897 return; 898 } 899 900 /* 901 * If we're supposed to increase the interval, do so. If it's 902 * currently zero (i.e., we haven't sent any packets yet), set 903 * it to initial_interval; otherwise, add to it a random 904 * number between zero and two times itself. On average, this 905 * means that it will double with every transmission. 906 */ 907 if (increase) { 908 if (!client->interval) 909 client->interval = config->initial_interval; 910 else { 911 client->interval += (arc4random() >> 2) % 912 (2 * client->interval); 913 } 914 915 /* Don't backoff past cutoff. */ 916 if (client->interval > config->backoff_cutoff) 917 client->interval = ((config->backoff_cutoff / 2) 918 + ((arc4random() >> 2) % 919 config->backoff_cutoff)); 920 } else if (!client->interval) 921 client->interval = config->initial_interval; 922 923 /* If the backoff would take us to the panic timeout, just use that 924 as the interval. */ 925 if (cur_time + client->interval > 926 client->first_sending + config->timeout) 927 client->interval = (client->first_sending + 928 config->timeout) - cur_time + 1; 929 930 /* Record the number of seconds since we started sending. */ 931 if (interval < 65536) 932 client->packet.secs = htons(interval); 933 else 934 client->packet.secs = htons(65535); 935 client->secs = client->packet.secs; 936 937 note("DHCPDISCOVER on %s to %s port %d interval %ld", 938 ifi->name, inet_ntoa(sockaddr_broadcast.sin_addr), 939 ntohs(sockaddr_broadcast.sin_port), client->interval); 940 941 /* Send out a packet. */ 942 send_packet(inaddr_any, &sockaddr_broadcast, NULL); 943 944 set_timeout(cur_time + client->interval, send_discover); 945 } 946 947 /* 948 * state_panic gets called if we haven't received any offers in a preset 949 * amount of time. When this happens, we try to use existing leases 950 * that haven't yet expired, and failing that, we call the client script 951 * and hope it can do something. 952 */ 953 void 954 state_panic(void) 955 { 956 struct client_lease *loop = client->active; 957 struct client_lease *lp; 958 959 note("No DHCPOFFERS received."); 960 961 /* We may not have an active lease, but we may have some 962 predefined leases that we can try. */ 963 if (!client->active && client->leases) 964 goto activate_next; 965 966 /* Run through the list of leases and see if one can be used. */ 967 while (client->active) { 968 if (client->active->expiry > cur_time) { 969 note("Trying recorded lease %s", 970 piaddr(client->active->address)); 971 /* Run the client script with the existing 972 parameters. */ 973 script_init("TIMEOUT"); 974 script_write_params("new_", client->active); 975 976 /* If the old lease is still good and doesn't 977 yet need renewal, go into BOUND state and 978 timeout at the renewal time. */ 979 if (!script_go()) { 980 if (cur_time < 981 client->active->renewal) { 982 client->state = S_BOUND; 983 note("bound: renewal in %ld seconds.", 984 client->active->renewal - 985 cur_time); 986 set_timeout(client->active->renewal, 987 state_bound); 988 } else { 989 client->state = S_BOUND; 990 note("bound: immediate renewal."); 991 state_bound(); 992 } 993 reinitialize_interface(); 994 go_daemon(); 995 return; 996 } 997 } 998 999 /* If there are no other leases, give up. */ 1000 if (!client->leases) { 1001 client->leases = client->active; 1002 client->active = NULL; 1003 break; 1004 } 1005 1006 activate_next: 1007 /* Otherwise, put the active lease at the end of the 1008 lease list, and try another lease.. */ 1009 for (lp = client->leases; lp->next; lp = lp->next) 1010 ; 1011 lp->next = client->active; 1012 if (lp->next) 1013 lp->next->next = NULL; 1014 client->active = client->leases; 1015 client->leases = client->leases->next; 1016 1017 /* If we already tried this lease, we've exhausted the 1018 set of leases, so we might as well give up for 1019 now. */ 1020 if (client->active == loop) 1021 break; 1022 else if (!loop) 1023 loop = client->active; 1024 } 1025 1026 /* No leases were available, or what was available didn't work, so 1027 tell the shell script that we failed to allocate an address, 1028 and try again later. */ 1029 note("No working leases in persistent database - sleeping."); 1030 script_init("FAIL"); 1031 script_go(); 1032 client->state = S_INIT; 1033 set_timeout(cur_time + config->retry_interval, state_init); 1034 go_daemon(); 1035 } 1036 1037 void 1038 send_request(void) 1039 { 1040 struct sockaddr_in destination; 1041 struct in_addr from; 1042 int interval; 1043 1044 /* Figure out how long it's been since we started transmitting. */ 1045 interval = cur_time - client->first_sending; 1046 1047 /* If we're in the INIT-REBOOT or REQUESTING state and we're 1048 past the reboot timeout, go to INIT and see if we can 1049 DISCOVER an address... */ 1050 /* XXX In the INIT-REBOOT state, if we don't get an ACK, it 1051 means either that we're on a network with no DHCP server, 1052 or that our server is down. In the latter case, assuming 1053 that there is a backup DHCP server, DHCPDISCOVER will get 1054 us a new address, but we could also have successfully 1055 reused our old address. In the former case, we're hosed 1056 anyway. This is not a win-prone situation. */ 1057 if ((client->state == S_REBOOTING || 1058 client->state == S_REQUESTING) && 1059 interval > config->reboot_timeout) { 1060 client->state = S_INIT; 1061 cancel_timeout(); 1062 state_init(); 1063 return; 1064 } 1065 1066 /* If the lease has expired, relinquish the address and go back 1067 to the INIT state. */ 1068 if (client->state != S_REQUESTING && 1069 cur_time > client->active->expiry) { 1070 /* Run the client script with the new parameters. */ 1071 script_init("EXPIRE"); 1072 script_write_params("old_", client->active); 1073 script_go(); 1074 1075 client->state = S_INIT; 1076 state_init(); 1077 return; 1078 } 1079 1080 /* Do the exponential backoff... */ 1081 if (!client->interval) 1082 client->interval = config->initial_interval; 1083 else 1084 client->interval += ((arc4random() >> 2) % 1085 (2 * client->interval)); 1086 1087 /* Don't backoff past cutoff. */ 1088 if (client->interval > config->backoff_cutoff) 1089 client->interval = ((config->backoff_cutoff / 2) + 1090 ((arc4random() >> 2) % client->interval)); 1091 1092 /* If the backoff would take us to the expiry time, just set the 1093 timeout to the expiry time. */ 1094 if (client->state != S_REQUESTING && cur_time + client->interval > 1095 client->active->expiry) 1096 client->interval = client->active->expiry - cur_time + 1; 1097 1098 /* If the lease T2 time has elapsed, or if we're not yet bound, 1099 broadcast the DHCPREQUEST rather than unicasting. */ 1100 memset(&destination, 0, sizeof(destination)); 1101 if (client->state == S_REQUESTING || 1102 client->state == S_REBOOTING || 1103 cur_time > client->active->rebind) 1104 destination.sin_addr.s_addr = INADDR_BROADCAST; 1105 else 1106 memcpy(&destination.sin_addr.s_addr, client->destination.iabuf, 1107 sizeof(destination.sin_addr.s_addr)); 1108 destination.sin_port = htons(REMOTE_PORT); 1109 destination.sin_family = AF_INET; 1110 destination.sin_len = sizeof(destination); 1111 1112 if (client->state != S_REQUESTING) 1113 memcpy(&from, client->active->address.iabuf, sizeof(from)); 1114 else 1115 from.s_addr = INADDR_ANY; 1116 1117 /* Record the number of seconds since we started sending. */ 1118 if (client->state == S_REQUESTING) 1119 client->packet.secs = client->secs; 1120 else { 1121 if (interval < 65536) 1122 client->packet.secs = htons(interval); 1123 else 1124 client->packet.secs = htons(65535); 1125 } 1126 1127 note("DHCPREQUEST on %s to %s port %d", ifi->name, 1128 inet_ntoa(destination.sin_addr), ntohs(destination.sin_port)); 1129 1130 /* Send out a packet. */ 1131 send_packet(from, &destination, NULL); 1132 1133 set_timeout(cur_time + client->interval, send_request); 1134 } 1135 1136 void 1137 send_decline(void) 1138 { 1139 note("DHCPDECLINE on %s to %s port %d", ifi->name, 1140 inet_ntoa(sockaddr_broadcast.sin_addr), 1141 ntohs(sockaddr_broadcast.sin_port)); 1142 1143 /* Send out a packet. */ 1144 send_packet(inaddr_any, &sockaddr_broadcast, NULL); 1145 } 1146 1147 void 1148 make_discover(struct client_lease *lease) 1149 { 1150 unsigned char discover = DHCPDISCOVER; 1151 struct option_data options[256]; 1152 int i; 1153 1154 memset(options, 0, sizeof(options)); 1155 memset(&client->packet, 0, sizeof(client->packet)); 1156 1157 /* Set DHCP_MESSAGE_TYPE to DHCPDISCOVER */ 1158 i = DHO_DHCP_MESSAGE_TYPE; 1159 options[i].data = &discover; 1160 options[i].len = sizeof(discover); 1161 1162 /* Request the options we want */ 1163 i = DHO_DHCP_PARAMETER_REQUEST_LIST; 1164 options[i].data = config->requested_options; 1165 options[i].len = config->requested_option_count; 1166 1167 /* If we had an address, try to get it again. */ 1168 if (lease) { 1169 client->requested_address = lease->address; 1170 i = DHO_DHCP_REQUESTED_ADDRESS; 1171 options[i].data = lease->address.iabuf; 1172 options[i].len = lease->address.len; 1173 } else 1174 client->requested_address.len = 0; 1175 1176 /* Send any options requested in the config file. */ 1177 for (i = 0; i < 256; i++) 1178 if (!options[i].data && 1179 config->send_options[i].data) { 1180 options[i].data = config->send_options[i].data; 1181 options[i].len = config->send_options[i].len; 1182 } 1183 1184 /* Set up the option buffer to fit in a minimal UDP packet. */ 1185 i = cons_options(options); 1186 if (i == -1 || client->packet.options[i] != DHO_END) 1187 error("options do not fit in DHCPDISCOVER packet."); 1188 client->packet_length = DHCP_FIXED_NON_UDP+i+1; 1189 if (client->packet_length < BOOTP_MIN_LEN) 1190 client->packet_length = BOOTP_MIN_LEN; 1191 1192 client->packet.op = BOOTREQUEST; 1193 client->packet.htype = ifi->hw_address.htype; 1194 client->packet.hlen = ifi->hw_address.hlen; 1195 client->packet.hops = 0; 1196 client->packet.xid = arc4random(); 1197 client->packet.secs = 0; /* filled in by send_discover. */ 1198 client->packet.flags = 0; 1199 1200 memset(&client->packet.ciaddr, 0, sizeof(client->packet.ciaddr)); 1201 memset(&client->packet.yiaddr, 0, sizeof(client->packet.yiaddr)); 1202 memset(&client->packet.siaddr, 0, sizeof(client->packet.siaddr)); 1203 memset(&client->packet.giaddr, 0, sizeof(client->packet.giaddr)); 1204 memcpy(client->packet.chaddr, ifi->hw_address.haddr, 1205 ifi->hw_address.hlen); 1206 } 1207 1208 void 1209 make_request(struct client_lease * lease) 1210 { 1211 unsigned char request = DHCPREQUEST; 1212 struct option_data options[256]; 1213 int i; 1214 1215 memset(options, 0, sizeof(options)); 1216 memset(&client->packet, 0, sizeof(client->packet)); 1217 1218 /* Set DHCP_MESSAGE_TYPE to DHCPREQUEST */ 1219 i = DHO_DHCP_MESSAGE_TYPE; 1220 options[i].data = &request; 1221 options[i].len = sizeof(request); 1222 1223 /* Request the options we want */ 1224 i = DHO_DHCP_PARAMETER_REQUEST_LIST; 1225 options[i].data = config->requested_options; 1226 options[i].len = config->requested_option_count; 1227 1228 /* If we are requesting an address that hasn't yet been assigned 1229 to us, use the DHCP Requested Address option. */ 1230 if (client->state == S_REQUESTING) { 1231 /* Send back the server identifier... */ 1232 i = DHO_DHCP_SERVER_IDENTIFIER; 1233 options[i].data = lease->options[i].data; 1234 options[i].len = lease->options[i].len; 1235 } 1236 if (client->state == S_REQUESTING || 1237 client->state == S_REBOOTING) { 1238 client->requested_address = lease->address; 1239 i = DHO_DHCP_REQUESTED_ADDRESS; 1240 options[i].data = lease->address.iabuf; 1241 options[i].len = lease->address.len; 1242 } else 1243 client->requested_address.len = 0; 1244 1245 /* Send any options requested in the config file. */ 1246 for (i = 0; i < 256; i++) 1247 if (!options[i].data && config->send_options[i].data) { 1248 options[i].data = config->send_options[i].data; 1249 options[i].len = config->send_options[i].len; 1250 } 1251 1252 /* Set up the option buffer to fit in a minimal UDP packet. */ 1253 i = cons_options(options); 1254 if (i == -1 || client->packet.options[i] != DHO_END) 1255 error("options do not fit in DHCPREQUEST packet."); 1256 client->packet_length = DHCP_FIXED_NON_UDP+i+1; 1257 if (client->packet_length < BOOTP_MIN_LEN) 1258 client->packet_length = BOOTP_MIN_LEN; 1259 1260 client->packet.op = BOOTREQUEST; 1261 client->packet.htype = ifi->hw_address.htype; 1262 client->packet.hlen = ifi->hw_address.hlen; 1263 client->packet.hops = 0; 1264 client->packet.xid = client->xid; 1265 client->packet.secs = 0; /* Filled in by send_request. */ 1266 client->packet.flags = 0; 1267 1268 /* If we own the address we're requesting, put it in ciaddr; 1269 otherwise set ciaddr to zero. */ 1270 if (client->state == S_BOUND || 1271 client->state == S_RENEWING || 1272 client->state == S_REBINDING) { 1273 memcpy(&client->packet.ciaddr, 1274 lease->address.iabuf, lease->address.len); 1275 } else { 1276 memset(&client->packet.ciaddr, 0, 1277 sizeof(client->packet.ciaddr)); 1278 } 1279 1280 memset(&client->packet.yiaddr, 0, sizeof(client->packet.yiaddr)); 1281 memset(&client->packet.siaddr, 0, sizeof(client->packet.siaddr)); 1282 memset(&client->packet.giaddr, 0, sizeof(client->packet.giaddr)); 1283 memcpy(client->packet.chaddr, ifi->hw_address.haddr, 1284 ifi->hw_address.hlen); 1285 } 1286 1287 void 1288 make_decline(struct client_lease *lease) 1289 { 1290 struct option_data options[256]; 1291 unsigned char decline = DHCPDECLINE; 1292 int i; 1293 1294 memset(options, 0, sizeof(options)); 1295 memset(&client->packet, 0, sizeof(client->packet)); 1296 1297 /* Set DHCP_MESSAGE_TYPE to DHCPDECLINE */ 1298 i = DHO_DHCP_MESSAGE_TYPE; 1299 options[i].data = &decline; 1300 options[i].len = sizeof(decline); 1301 1302 /* Send back the server identifier... */ 1303 i = DHO_DHCP_SERVER_IDENTIFIER; 1304 options[i].data = lease->options[i].data; 1305 options[i].len = lease->options[i].len; 1306 1307 /* Send back the address we're declining. */ 1308 i = DHO_DHCP_REQUESTED_ADDRESS; 1309 options[i].data = lease->address.iabuf; 1310 options[i].len = lease->address.len; 1311 1312 /* Send the uid if the user supplied one. */ 1313 i = DHO_DHCP_CLIENT_IDENTIFIER; 1314 if (config->send_options[i].len) { 1315 options[i].data = config->send_options[i].data; 1316 options[i].len = config->send_options[i].len; 1317 } 1318 1319 /* Set up the option buffer to fit in a minimal UDP packet. */ 1320 i = cons_options(options); 1321 if (i == -1 || client->packet.options[i] != DHO_END) 1322 error("options do not fit in DHCPDECLINE packet."); 1323 client->packet_length = DHCP_FIXED_NON_UDP+i+1; 1324 if (client->packet_length < BOOTP_MIN_LEN) 1325 client->packet_length = BOOTP_MIN_LEN; 1326 1327 client->packet.op = BOOTREQUEST; 1328 client->packet.htype = ifi->hw_address.htype; 1329 client->packet.hlen = ifi->hw_address.hlen; 1330 client->packet.hops = 0; 1331 client->packet.xid = client->xid; 1332 client->packet.secs = 0; /* Filled in by send_request. */ 1333 client->packet.flags = 0; 1334 1335 /* ciaddr must always be zero. */ 1336 memset(&client->packet.ciaddr, 0, sizeof(client->packet.ciaddr)); 1337 memset(&client->packet.yiaddr, 0, sizeof(client->packet.yiaddr)); 1338 memset(&client->packet.siaddr, 0, sizeof(client->packet.siaddr)); 1339 memset(&client->packet.giaddr, 0, sizeof(client->packet.giaddr)); 1340 memcpy(client->packet.chaddr, ifi->hw_address.haddr, 1341 ifi->hw_address.hlen); 1342 } 1343 1344 void 1345 free_client_lease(struct client_lease *lease) 1346 { 1347 int i; 1348 1349 if (lease->server_name) 1350 free(lease->server_name); 1351 if (lease->filename) 1352 free(lease->filename); 1353 for (i = 0; i < 256; i++) { 1354 if (lease->options[i].len) 1355 free(lease->options[i].data); 1356 } 1357 free(lease); 1358 } 1359 1360 void 1361 rewrite_client_leases(void) 1362 { 1363 struct client_lease *lp; 1364 1365 if (!leaseFile) /* XXX */ 1366 error("lease file not open"); 1367 1368 fflush(leaseFile); 1369 rewind(leaseFile); 1370 1371 for (lp = client->leases; lp; lp = lp->next) { 1372 if (client->active && addr_eq(lp->address, 1373 client->active->address)) 1374 continue; 1375 write_client_lease(lp); 1376 } 1377 1378 if (client->active) 1379 write_client_lease(client->active); 1380 1381 fflush(leaseFile); 1382 ftruncate(fileno(leaseFile), ftello(leaseFile)); 1383 fsync(fileno(leaseFile)); 1384 } 1385 1386 void 1387 write_client_lease(struct client_lease *lease) 1388 { 1389 struct tm *t; 1390 int i; 1391 1392 /* If the lease came from the config file, we don't need to stash 1393 a copy in the lease database. */ 1394 if (lease->is_static) 1395 return; 1396 1397 if (!leaseFile) /* XXX */ 1398 error("lease file not open"); 1399 1400 fprintf(leaseFile, "lease {\n"); 1401 if (lease->is_bootp) 1402 fprintf(leaseFile, " bootp;\n"); 1403 fprintf(leaseFile, " interface \"%s\";\n", ifi->name); 1404 fprintf(leaseFile, " fixed-address %s;\n", piaddr(lease->address)); 1405 if (lease->filename) 1406 fprintf(leaseFile, " filename \"%s\";\n", lease->filename); 1407 if (lease->server_name) 1408 fprintf(leaseFile, " server-name \"%s\";\n", 1409 lease->server_name); 1410 for (i = 0; i < 256; i++) 1411 if (lease->options[i].len) 1412 fprintf(leaseFile, " option %s %s;\n", 1413 dhcp_options[i].name, 1414 pretty_print_option(i, lease->options[i].data, 1415 lease->options[i].len, 1, 1)); 1416 1417 t = gmtime(&lease->renewal); 1418 fprintf(leaseFile, " renew %d %d/%d/%d %02d:%02d:%02d;\n", 1419 t->tm_wday, t->tm_year + 1900, t->tm_mon + 1, t->tm_mday, 1420 t->tm_hour, t->tm_min, t->tm_sec); 1421 t = gmtime(&lease->rebind); 1422 fprintf(leaseFile, " rebind %d %d/%d/%d %02d:%02d:%02d;\n", 1423 t->tm_wday, t->tm_year + 1900, t->tm_mon + 1, t->tm_mday, 1424 t->tm_hour, t->tm_min, t->tm_sec); 1425 t = gmtime(&lease->expiry); 1426 fprintf(leaseFile, " expire %d %d/%d/%d %02d:%02d:%02d;\n", 1427 t->tm_wday, t->tm_year + 1900, t->tm_mon + 1, t->tm_mday, 1428 t->tm_hour, t->tm_min, t->tm_sec); 1429 fprintf(leaseFile, "}\n"); 1430 fflush(leaseFile); 1431 } 1432 1433 void 1434 script_init(char *reason) 1435 { 1436 size_t len; 1437 struct imsg_hdr hdr; 1438 struct buf *buf; 1439 1440 hdr.code = IMSG_SCRIPT_INIT; 1441 hdr.len = sizeof(struct imsg_hdr) + sizeof(size_t) + strlen(reason); 1442 buf = buf_open(hdr.len); 1443 1444 buf_add(buf, &hdr, sizeof(hdr)); 1445 len = strlen(reason); 1446 buf_add(buf, &len, sizeof(len)); 1447 buf_add(buf, reason, len); 1448 1449 buf_close(privfd, buf); 1450 } 1451 1452 void 1453 priv_script_init(char *reason) 1454 { 1455 client->scriptEnvsize = 100; 1456 if (client->scriptEnv == NULL) 1457 client->scriptEnv = 1458 calloc(client->scriptEnvsize, sizeof(char *)); 1459 if (client->scriptEnv == NULL) 1460 error("script_init: no memory for environment"); 1461 1462 client->scriptEnv[0] = strdup(CLIENT_PATH); 1463 if (client->scriptEnv[0] == NULL) 1464 error("script_init: no memory for environment"); 1465 1466 client->scriptEnv[1] = NULL; 1467 1468 script_set_env("", "interface", ifi->name); 1469 1470 script_set_env("", "reason", reason); 1471 } 1472 1473 void 1474 priv_script_write_params(char *prefix, struct client_lease *lease) 1475 { 1476 u_int8_t dbuf[1500]; 1477 int i, len = 0; 1478 char tbuf[128]; 1479 1480 script_set_env(prefix, "ip_address", piaddr(lease->address)); 1481 1482 if (lease->options[DHO_SUBNET_MASK].len && 1483 (lease->options[DHO_SUBNET_MASK].len < 1484 sizeof(lease->address.iabuf))) { 1485 struct iaddr netmask, subnet, broadcast; 1486 1487 memcpy(netmask.iabuf, lease->options[DHO_SUBNET_MASK].data, 1488 lease->options[DHO_SUBNET_MASK].len); 1489 netmask.len = lease->options[DHO_SUBNET_MASK].len; 1490 1491 subnet = subnet_number(lease->address, netmask); 1492 if (subnet.len) { 1493 script_set_env(prefix, "network_number", 1494 piaddr(subnet)); 1495 if (!lease->options[DHO_BROADCAST_ADDRESS].len) { 1496 broadcast = broadcast_addr(subnet, netmask); 1497 if (broadcast.len) 1498 script_set_env(prefix, 1499 "broadcast_address", 1500 piaddr(broadcast)); 1501 } 1502 } 1503 } 1504 1505 if (lease->filename) 1506 script_set_env(prefix, "filename", lease->filename); 1507 if (lease->server_name) 1508 script_set_env(prefix, "server_name", 1509 lease->server_name); 1510 for (i = 0; i < 256; i++) { 1511 u_int8_t *dp = NULL; 1512 1513 if (config->defaults[i].len) { 1514 if (lease->options[i].len) { 1515 switch (config->default_actions[i]) { 1516 case ACTION_DEFAULT: 1517 dp = lease->options[i].data; 1518 len = lease->options[i].len; 1519 break; 1520 case ACTION_SUPERSEDE: 1521 supersede: 1522 dp = config->defaults[i].data; 1523 len = config->defaults[i].len; 1524 break; 1525 case ACTION_PREPEND: 1526 len = config->defaults[i].len + 1527 lease->options[i].len; 1528 if (len >= sizeof(dbuf)) { 1529 warning("no space to %s %s", 1530 "prepend option", 1531 dhcp_options[i].name); 1532 goto supersede; 1533 } 1534 dp = dbuf; 1535 memcpy(dp, 1536 config->defaults[i].data, 1537 config->defaults[i].len); 1538 memcpy(dp + 1539 config->defaults[i].len, 1540 lease->options[i].data, 1541 lease->options[i].len); 1542 dp[len] = '\0'; 1543 break; 1544 case ACTION_APPEND: 1545 len = config->defaults[i].len + 1546 lease->options[i].len; 1547 if (len >= sizeof(dbuf)) { 1548 warning("no space to %s %s", 1549 "append option", 1550 dhcp_options[i].name); 1551 goto supersede; 1552 } 1553 dp = dbuf; 1554 memcpy(dp, lease->options[i].data, 1555 lease->options[i].len); 1556 memcpy(dp + lease->options[i].len, 1557 config->defaults[i].data, 1558 config->defaults[i].len); 1559 dp[len] = '\0'; 1560 } 1561 } else { 1562 dp = config->defaults[i].data; 1563 len = config->defaults[i].len; 1564 } 1565 } else if (lease->options[i].len) { 1566 len = lease->options[i].len; 1567 dp = lease->options[i].data; 1568 } else { 1569 len = 0; 1570 } 1571 if (len) { 1572 char name[256]; 1573 1574 if (dhcp_option_ev_name(name, sizeof(name), 1575 &dhcp_options[i])) 1576 script_set_env(prefix, name, 1577 pretty_print_option(i, dp, len, 0, 0)); 1578 } 1579 } 1580 snprintf(tbuf, sizeof(tbuf), "%d", (int)lease->expiry); 1581 script_set_env(prefix, "expiry", tbuf); 1582 } 1583 1584 void 1585 script_write_params(char *prefix, struct client_lease *lease) 1586 { 1587 size_t fn_len = 0, sn_len = 0, pr_len = 0; 1588 struct imsg_hdr hdr; 1589 struct buf *buf; 1590 int i; 1591 1592 if (lease->filename != NULL) 1593 fn_len = strlen(lease->filename); 1594 if (lease->server_name != NULL) 1595 sn_len = strlen(lease->server_name); 1596 if (prefix != NULL) 1597 pr_len = strlen(prefix); 1598 1599 hdr.code = IMSG_SCRIPT_WRITE_PARAMS; 1600 hdr.len = sizeof(hdr) + sizeof(struct client_lease) + 1601 sizeof(size_t) + fn_len + sizeof(size_t) + sn_len + 1602 sizeof(size_t) + pr_len; 1603 1604 for (i = 0; i < 256; i++) 1605 hdr.len += sizeof(int) + lease->options[i].len; 1606 1607 scripttime = time(NULL); 1608 1609 buf = buf_open(hdr.len); 1610 1611 buf_add(buf, &hdr, sizeof(hdr)); 1612 buf_add(buf, lease, sizeof(struct client_lease)); 1613 buf_add(buf, &fn_len, sizeof(fn_len)); 1614 buf_add(buf, lease->filename, fn_len); 1615 buf_add(buf, &sn_len, sizeof(sn_len)); 1616 buf_add(buf, lease->server_name, sn_len); 1617 buf_add(buf, &pr_len, sizeof(pr_len)); 1618 buf_add(buf, prefix, pr_len); 1619 1620 for (i = 0; i < 256; i++) { 1621 buf_add(buf, &lease->options[i].len, 1622 sizeof(lease->options[i].len)); 1623 buf_add(buf, lease->options[i].data, 1624 lease->options[i].len); 1625 } 1626 1627 buf_close(privfd, buf); 1628 } 1629 1630 int 1631 script_go(void) 1632 { 1633 struct imsg_hdr hdr; 1634 struct buf *buf; 1635 int ret; 1636 1637 scripttime = time(NULL); 1638 1639 hdr.code = IMSG_SCRIPT_GO; 1640 hdr.len = sizeof(struct imsg_hdr); 1641 1642 buf = buf_open(hdr.len); 1643 1644 buf_add(buf, &hdr, sizeof(hdr)); 1645 buf_close(privfd, buf); 1646 1647 bzero(&hdr, sizeof(hdr)); 1648 buf_read(privfd, &hdr, sizeof(hdr)); 1649 if (hdr.code != IMSG_SCRIPT_GO_RET) 1650 error("unexpected msg type %u", hdr.code); 1651 if (hdr.len != sizeof(hdr) + sizeof(int)) 1652 error("received corrupted message"); 1653 buf_read(privfd, &ret, sizeof(ret)); 1654 1655 return (ret); 1656 } 1657 1658 int 1659 priv_script_go(void) 1660 { 1661 char *scriptName, *argv[2], **envp; 1662 int pid, wpid, wstatus; 1663 1664 scripttime = time(NULL); 1665 1666 scriptName = config->script_name; 1667 envp = client->scriptEnv; 1668 1669 argv[0] = scriptName; 1670 argv[1] = NULL; 1671 1672 pid = fork(); 1673 if (pid < 0) { 1674 error("fork: %m"); 1675 wstatus = 0; 1676 } else if (pid) { 1677 do { 1678 wpid = wait(&wstatus); 1679 } while (wpid != pid && wpid > 0); 1680 if (wpid < 0) { 1681 error("wait: %m"); 1682 wstatus = 0; 1683 } 1684 } else { 1685 execve(scriptName, argv, envp); 1686 error("execve (%s, ...): %m", scriptName); 1687 } 1688 1689 script_flush_env(); 1690 1691 return (WEXITSTATUS(wstatus)); 1692 } 1693 1694 void 1695 script_set_env(const char *prefix, const char *name, const char *value) 1696 { 1697 int i, j, namelen; 1698 1699 namelen = strlen(name); 1700 1701 for (i = 0; client->scriptEnv[i]; i++) 1702 if (strncmp(client->scriptEnv[i], name, namelen) == 0 && 1703 client->scriptEnv[i][namelen] == '=') 1704 break; 1705 1706 if (client->scriptEnv[i]) 1707 /* Reuse the slot. */ 1708 free(client->scriptEnv[i]); 1709 else { 1710 /* New variable. Expand if necessary. */ 1711 if (i >= client->scriptEnvsize - 1) { 1712 char **newscriptEnv; 1713 int newscriptEnvsize = client->scriptEnvsize + 50; 1714 1715 newscriptEnv = realloc(client->scriptEnv, 1716 newscriptEnvsize); 1717 if (newscriptEnv == NULL) { 1718 free(client->scriptEnv); 1719 client->scriptEnv = NULL; 1720 client->scriptEnvsize = 0; 1721 error("script_set_env: no memory for variable"); 1722 } 1723 client->scriptEnv = newscriptEnv; 1724 client->scriptEnvsize = newscriptEnvsize; 1725 } 1726 /* need to set the NULL pointer at end of array beyond 1727 the new slot. */ 1728 client->scriptEnv[i + 1] = NULL; 1729 } 1730 /* Allocate space and format the variable in the appropriate slot. */ 1731 client->scriptEnv[i] = malloc(strlen(prefix) + strlen(name) + 1 + 1732 strlen(value) + 1); 1733 if (client->scriptEnv[i] == NULL) 1734 error("script_set_env: no memory for variable assignment"); 1735 1736 /* No `` or $() command substitution allowed in environment values! */ 1737 for (j = 0; j < strlen(value); j++) 1738 switch (value[j]) { 1739 case '`': 1740 case '$': 1741 error("illegal character (%c) in value '%s'", value[j], 1742 value); 1743 /* not reached */ 1744 } 1745 snprintf(client->scriptEnv[i], strlen(prefix) + strlen(name) + 1746 1 + strlen(value) + 1, "%s%s=%s", prefix, name, value); 1747 } 1748 1749 void 1750 script_flush_env(void) 1751 { 1752 int i; 1753 1754 for (i = 0; client->scriptEnv[i]; i++) { 1755 free(client->scriptEnv[i]); 1756 client->scriptEnv[i] = NULL; 1757 } 1758 client->scriptEnvsize = 0; 1759 } 1760 1761 int 1762 dhcp_option_ev_name(char *buf, size_t buflen, const struct option *option) 1763 { 1764 size_t i; 1765 1766 for (i = 0; option->name[i]; i++) { 1767 if (i + 1 == buflen) 1768 return 0; 1769 if (option->name[i] == '-') 1770 buf[i] = '_'; 1771 else 1772 buf[i] = option->name[i]; 1773 } 1774 1775 buf[i] = 0; 1776 return 1; 1777 } 1778 1779 void 1780 go_daemon(void) 1781 { 1782 static int state = 0; 1783 1784 if (no_daemon || state) 1785 return; 1786 1787 state = 1; 1788 1789 /* Stop logging to stderr... */ 1790 log_perror = 0; 1791 1792 if (daemon(1, 0) == -1) 1793 error("daemon"); 1794 1795 /* we are chrooted, daemon(3) fails to open /dev/null */ 1796 if (nullfd != -1) { 1797 dup2(nullfd, STDIN_FILENO); 1798 dup2(nullfd, STDOUT_FILENO); 1799 dup2(nullfd, STDERR_FILENO); 1800 close(nullfd); 1801 nullfd = -1; 1802 } 1803 } 1804 1805 int 1806 check_option(struct client_lease *l, int option) 1807 { 1808 char *opbuf; 1809 char *sbuf; 1810 1811 /* we use this, since this is what gets passed to dhclient-script */ 1812 1813 opbuf = pretty_print_option(option, l->options[option].data, 1814 l->options[option].len, 0, 0); 1815 1816 sbuf = option_as_string(option, l->options[option].data, 1817 l->options[option].len); 1818 1819 switch (option) { 1820 case DHO_SUBNET_MASK: 1821 case DHO_SWAP_SERVER: 1822 case DHO_BROADCAST_ADDRESS: 1823 case DHO_DHCP_SERVER_IDENTIFIER: 1824 case DHO_ROUTER_SOLICITATION_ADDRESS: 1825 case DHO_DHCP_REQUESTED_ADDRESS: 1826 if (ipv4addrs(opbuf) == 0) { 1827 warning("Invalid IP address in option %s: %s", 1828 dhcp_options[option].name, opbuf); 1829 return (0); 1830 } 1831 if (l->options[option].len != 4) { /* RFC 2132 */ 1832 warning("warning: Only 1 IP address allowed in " 1833 "%s option; length %d, must be 4", 1834 dhcp_options[option].name, 1835 l->options[option].len); 1836 l->options[option].len = 4; 1837 } 1838 return (1); 1839 case DHO_TIME_SERVERS: 1840 case DHO_NAME_SERVERS: 1841 case DHO_ROUTERS: 1842 case DHO_DOMAIN_NAME_SERVERS: 1843 case DHO_LOG_SERVERS: 1844 case DHO_COOKIE_SERVERS: 1845 case DHO_LPR_SERVERS: 1846 case DHO_IMPRESS_SERVERS: 1847 case DHO_RESOURCE_LOCATION_SERVERS: 1848 case DHO_NIS_SERVERS: 1849 case DHO_NTP_SERVERS: 1850 case DHO_NETBIOS_NAME_SERVERS: 1851 case DHO_NETBIOS_DD_SERVER: 1852 case DHO_FONT_SERVERS: 1853 if (ipv4addrs(opbuf) == 0) { 1854 warning("Invalid IP address in option %s: %s", 1855 dhcp_options[option].name, opbuf); 1856 return (0); 1857 } 1858 return (1); 1859 case DHO_HOST_NAME: 1860 case DHO_DOMAIN_NAME: 1861 case DHO_NIS_DOMAIN: 1862 if (!res_hnok(sbuf)) { 1863 warning("Bogus Host Name option %d: %s (%s)", option, 1864 sbuf, opbuf); 1865 l->options[option].len = 0; 1866 free(l->options[option].data); 1867 } 1868 return (1); 1869 case DHO_PAD: 1870 case DHO_TIME_OFFSET: 1871 case DHO_BOOT_SIZE: 1872 case DHO_MERIT_DUMP: 1873 case DHO_ROOT_PATH: 1874 case DHO_EXTENSIONS_PATH: 1875 case DHO_IP_FORWARDING: 1876 case DHO_NON_LOCAL_SOURCE_ROUTING: 1877 case DHO_POLICY_FILTER: 1878 case DHO_MAX_DGRAM_REASSEMBLY: 1879 case DHO_DEFAULT_IP_TTL: 1880 case DHO_PATH_MTU_AGING_TIMEOUT: 1881 case DHO_PATH_MTU_PLATEAU_TABLE: 1882 case DHO_INTERFACE_MTU: 1883 case DHO_ALL_SUBNETS_LOCAL: 1884 case DHO_PERFORM_MASK_DISCOVERY: 1885 case DHO_MASK_SUPPLIER: 1886 case DHO_ROUTER_DISCOVERY: 1887 case DHO_STATIC_ROUTES: 1888 case DHO_TRAILER_ENCAPSULATION: 1889 case DHO_ARP_CACHE_TIMEOUT: 1890 case DHO_IEEE802_3_ENCAPSULATION: 1891 case DHO_DEFAULT_TCP_TTL: 1892 case DHO_TCP_KEEPALIVE_INTERVAL: 1893 case DHO_TCP_KEEPALIVE_GARBAGE: 1894 case DHO_VENDOR_ENCAPSULATED_OPTIONS: 1895 case DHO_NETBIOS_NODE_TYPE: 1896 case DHO_NETBIOS_SCOPE: 1897 case DHO_X_DISPLAY_MANAGER: 1898 case DHO_DHCP_LEASE_TIME: 1899 case DHO_DHCP_OPTION_OVERLOAD: 1900 case DHO_DHCP_MESSAGE_TYPE: 1901 case DHO_DHCP_PARAMETER_REQUEST_LIST: 1902 case DHO_DHCP_MESSAGE: 1903 case DHO_DHCP_MAX_MESSAGE_SIZE: 1904 case DHO_DHCP_RENEWAL_TIME: 1905 case DHO_DHCP_REBINDING_TIME: 1906 case DHO_DHCP_CLASS_IDENTIFIER: 1907 case DHO_DHCP_CLIENT_IDENTIFIER: 1908 case DHO_DHCP_USER_CLASS_ID: 1909 case DHO_TFTP_SERVER: 1910 case DHO_END: 1911 return (1); 1912 default: 1913 if (!unknown_ok) 1914 warning("unknown dhcp option value 0x%x", option); 1915 return (unknown_ok); 1916 } 1917 } 1918 1919 int 1920 res_hnok(const char *name) 1921 { 1922 const char *dn = name; 1923 int pch = '.', ch = *dn++; 1924 int warn = 0; 1925 1926 while (ch != '\0') { 1927 int nch = *dn++; 1928 1929 if (ch == '.') { 1930 ; 1931 } else if (pch == '.' || nch == '.' || nch == '\0') { 1932 if (!isalnum(ch)) 1933 return (0); 1934 } else if (!isalnum(ch) && ch != '-' && ch != '_') 1935 return (0); 1936 else if (ch == '_' && warn == 0) { 1937 warning("warning: hostname %s contains an " 1938 "underscore which violates RFC 952", name); 1939 warn++; 1940 } 1941 pch = ch, ch = nch; 1942 } 1943 return (1); 1944 } 1945 1946 /* Does buf consist only of dotted decimal ipv4 addrs? 1947 * return how many if so, 1948 * otherwise, return 0 1949 */ 1950 int 1951 ipv4addrs(char * buf) 1952 { 1953 struct in_addr jnk; 1954 int count = 0; 1955 1956 while (inet_aton(buf, &jnk) == 1){ 1957 count++; 1958 while (*buf == '.' || isdigit(*buf)) 1959 buf++; 1960 if (*buf == '\0') 1961 return (count); 1962 while (*buf == ' ') 1963 buf++; 1964 } 1965 return (0); 1966 } 1967 1968 char * 1969 option_as_string(unsigned int code, unsigned char *data, int len) 1970 { 1971 static char optbuf[32768]; /* XXX */ 1972 char *op = optbuf; 1973 int opleft = sizeof(optbuf); 1974 unsigned char *dp = data; 1975 1976 if (code > 255) 1977 error("option_as_string: bad code %d", code); 1978 1979 for (; dp < data + len; dp++) { 1980 if (!isascii(*dp) || !isprint(*dp)) { 1981 if (dp + 1 != data + len || *dp != 0) { 1982 size_t oplen; 1983 snprintf(op, opleft, "\\%03o", *dp); 1984 oplen = strlen(op); 1985 op += oplen; 1986 opleft -= oplen; 1987 } 1988 } else if (*dp == '"' || *dp == '\'' || *dp == '$' || 1989 *dp == '`' || *dp == '\\') { 1990 *op++ = '\\'; 1991 *op++ = *dp; 1992 opleft -= 2; 1993 } else { 1994 *op++ = *dp; 1995 opleft--; 1996 } 1997 } 1998 if (opleft < 1) 1999 goto toobig; 2000 *op = 0; 2001 return optbuf; 2002 toobig: 2003 warning("dhcp option too large"); 2004 return "<error>"; 2005 } 2006 2007 int 2008 fork_privchld(int fd, int fd2) 2009 { 2010 struct pollfd pfd[1]; 2011 int nfds, pfail = 0; 2012 2013 switch (fork()) { 2014 case -1: 2015 error("cannot fork"); 2016 break; 2017 case 0: 2018 break; 2019 default: 2020 return (0); 2021 } 2022 2023 if (chdir("/") == -1) 2024 error("chdir(\"/\")"); 2025 2026 setproctitle("%s [priv]", ifi->name); 2027 2028 dup2(nullfd, STDIN_FILENO); 2029 dup2(nullfd, STDOUT_FILENO); 2030 dup2(nullfd, STDERR_FILENO); 2031 close(nullfd); 2032 close(fd2); 2033 2034 for (;;) { 2035 pfd[0].fd = fd; 2036 pfd[0].events = POLLIN; 2037 if ((nfds = poll(pfd, 1, INFTIM)) == -1) 2038 if (errno != EINTR) 2039 error("poll error"); 2040 2041 /* 2042 * Handle temporary errors, but bail if they persist. 2043 */ 2044 if (nfds == 0 || !(pfd[0].revents & POLLIN)) { 2045 if (pfail > POLL_FAILURES) 2046 error("poll failed > %d times", POLL_FAILURES); 2047 sleep(pfail * POLL_FAILURE_WAIT); 2048 pfail++; 2049 continue; 2050 } 2051 2052 dispatch_imsg(fd); 2053 } 2054 } 2055 2056 void 2057 get_ifname(char *ifname, char *arg) 2058 { 2059 struct ifgroupreq ifgr; 2060 struct ifg_req *ifg; 2061 int s, len; 2062 2063 if (!strcmp(arg, "egress")) { 2064 s = socket(AF_INET, SOCK_DGRAM, 0); 2065 if (s == -1) 2066 error("socket error"); 2067 bzero(&ifgr, sizeof(ifgr)); 2068 strlcpy(ifgr.ifgr_name, "egress", sizeof(ifgr.ifgr_name)); 2069 if (ioctl(s, SIOCGIFGMEMB, (caddr_t)&ifgr) == -1) { 2070 if (errno == ENOENT) 2071 error("no interface in group egress found"); 2072 error("ioctl SIOCGIFGMEMB: %m"); 2073 } 2074 len = ifgr.ifgr_len; 2075 if ((ifgr.ifgr_groups = calloc(1, len)) == NULL) 2076 error("get_ifname"); 2077 if (ioctl(s, SIOCGIFGMEMB, (caddr_t)&ifgr) == -1) 2078 error("ioctl SIOCGIFGMEMB: %m"); 2079 2080 arg = NULL; 2081 for (ifg = ifgr.ifgr_groups; 2082 ifg && len >= sizeof(struct ifg_req); ifg++) { 2083 len -= sizeof(struct ifg_req); 2084 if (arg) 2085 error("too many interfaces in group egress"); 2086 arg = ifg->ifgrq_member; 2087 } 2088 2089 if (strlcpy(ifi->name, arg, IFNAMSIZ) >= IFNAMSIZ) 2090 error("Interface name too long: %m"); 2091 2092 free(ifgr.ifgr_groups); 2093 close(s); 2094 } else if (strlcpy(ifi->name, arg, IFNAMSIZ) >= IFNAMSIZ) 2095 error("Interface name too long"); 2096 } 2097