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<sys/vfscache.h>: Sync enum vtagtype with what we have.
[dragonfly.git] / sbin / dhclient / dhclient.c
blobeab66825ed90131925e749143a03c8d87af868cb
1 /*
2 * Copyright 2004 Henning Brauer <henning@openbsd.org>
3 * Copyright (c) 1995, 1996, 1997, 1998, 1999
4 * The Internet Software Consortium. All rights reserved.
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 *
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of The Internet Software Consortium nor the names
16 * of its contributors may be used to endorse or promote products derived
17 * from this software without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE INTERNET SOFTWARE CONSORTIUM AND
20 * CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
21 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
22 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
23 * DISCLAIMED. IN NO EVENT SHALL THE INTERNET SOFTWARE CONSORTIUM OR
24 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
25 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
26 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
27 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
28 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
30 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 *
33 * This software has been written for the Internet Software Consortium
34 * by Ted Lemon <mellon@fugue.com> in cooperation with Vixie
35 * Enterprises. To learn more about the Internet Software Consortium,
36 * see ``http://www.vix.com/isc''. To learn more about Vixie
37 * Enterprises, see ``http://www.vix.com''.
38 *
39 * This client was substantially modified and enhanced by Elliot Poger
40 * for use on Linux while he was working on the MosquitoNet project at
41 * Stanford.
42 *
43 * The current version owes much to Elliot's Linux enhancements, but
44 * was substantially reorganized and partially rewritten by Ted Lemon
45 * so as to use the same networking framework that the Internet Software
46 * Consortium DHCP server uses. Much system-specific configuration code
47 * was moved into a shell script so that as support for more operating
48 * systems is added, it will not be necessary to port and maintain
49 * system-specific configuration code to these operating systems - instead,
50 * the shell script can invoke the native tools to accomplish the same
51 * purpose.
52 */
53 #include <sys/ioctl.h>
54
55 #include <ctype.h>
56 #include <poll.h>
57 #include <pwd.h>
58 #include <signal.h>
59 #include <unistd.h>
60
61 #include "dhcpd.h"
62 #include "privsep.h"
63
64 #define CLIENT_PATH "PATH=/usr/bin:/usr/sbin:/bin:/sbin"
65 #define DEFAULT_LEASE_TIME 43200 /* 12 hours... */
66 #define TIME_MAX 2147483647
67 #define POLL_FAILURES 10
68 #define POLL_FAILURE_WAIT 1 /* Back off multiplier (seconds) */
69
70 char *path_dhclient_conf = _PATH_DHCLIENT_CONF;
71 char *path_dhclient_db = NULL;
72 char *orig_ifname;
73
74 int log_perror = 1;
75 int privfd;
76 int nullfd = -1;
77 int no_daemon;
78 int stayalive = 0;
79 int unknown_ok = 1;
80 int routefd = -1;
81 pid_t monitor_pid;
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 static void sig_handle(int sig);
101 static int killclient(int fd);
102
103 time_t scripttime;
104 static FILE *leaseFile;
105
106 int
107 findproto(char *cp, int n)
108 {
109 struct sockaddr *sa;
110 int i;
111
112 if (n == 0)
113 return -1;
114 for (i = 1; i; i <<= 1) {
115 if (i & n) {
116 sa = (struct sockaddr *)cp;
117 switch (i) {
118 case RTA_IFA:
119 case RTA_DST:
120 case RTA_GATEWAY:
121 case RTA_NETMASK:
122 if (sa->sa_family == AF_INET)
123 return AF_INET;
124 if (sa->sa_family == AF_INET6)
125 return AF_INET6;
126 break;
127 case RTA_IFP:
128 break;
129 }
130 RT_ADVANCE(cp, sa);
131 }
132 }
133 return (-1);
134 }
135
136 struct sockaddr *
137 get_ifa(char *cp, int n)
138 {
139 struct sockaddr *sa;
140 int i;
141
142 if (n == 0)
143 return (NULL);
144 for (i = 1; i; i <<= 1)
145 if (i & n) {
146 sa = (struct sockaddr *)cp;
147 if (i == RTA_IFA)
148 return (sa);
149 RT_ADVANCE(cp, sa);
150 }
151
152 return (NULL);
153 }
154 struct iaddr defaddr = { .len = 4 }; /* NULL is for silence warnings */
155
156 void
157 routehandler(void)
158 {
159 int linkstat;
160 char msg[2048];
161 struct rt_msghdr *rtm;
162 struct if_msghdr *ifm;
163 struct ifa_msghdr *ifam;
164 struct if_announcemsghdr *ifan;
165 struct client_lease *l;
166 struct sockaddr *sa;
167 struct iaddr a;
168 ssize_t n;
169 char *errmsg, buf[64];
170
171 do {
172 n = read(routefd, &msg, sizeof(msg));
173 } while (n == -1 && errno == EINTR);
174
175 rtm = (struct rt_msghdr *)msg;
176 if (n < sizeof(rtm->rtm_msglen) || n < rtm->rtm_msglen ||
177 rtm->rtm_version != RTM_VERSION)
178 return;
179
180 switch (rtm->rtm_type) {
181 case RTM_NEWADDR:
182 ifam = (struct ifa_msghdr *)rtm;
183 if (ifam->ifam_index != ifi->index)
184 break;
185 if (findproto((char *)(ifam + 1), ifam->ifam_addrs) != AF_INET)
186 break;
187 sa = get_ifa((char *)(ifam + 1), ifam->ifam_addrs);
188 if (sa == NULL) {
189 errmsg = "sa == NULL";
190 goto die;
191 }
192
193 if ((a.len = sizeof(struct in_addr)) > sizeof(a.iabuf))
194 error("king bula sez: len mismatch");
195 memcpy(a.iabuf, &((struct sockaddr_in *)sa)->sin_addr, a.len);
196 if (addr_eq(a, defaddr))
197 break;
198
199 /* state_panic() can try unexpired existing leases */
200 if (client->active && addr_eq(a, client->active->address))
201 break;
202 for (l = client->leases; l != NULL; l = l->next)
203 if (addr_eq(a, l->address))
204 break;
205
206 if (l != NULL)
207 /* new addr is the one we set */
208 break;
209 snprintf(buf, sizeof(buf), "%s: %s",
210 "new address not one we set", piaddr(a));
211 errmsg = buf;
212 goto die;
213 case RTM_DELADDR:
214 ifam = (struct ifa_msghdr *)rtm;
215 if (ifam->ifam_index != ifi->index)
216 break;
217 if (findproto((char *)(ifam + 1), ifam->ifam_addrs) != AF_INET)
218 break;
219 /* XXX check addrs like RTM_NEWADDR instead of this? */
220 if (scripttime == 0 || time(NULL) < scripttime + 10)
221 break;
222 errmsg = "interface address deleted";
223 goto die;
224 case RTM_IFINFO:
225 ifm = (struct if_msghdr *)rtm;
226 if (ifm->ifm_index != ifi->index)
227 break;
228 if ((rtm->rtm_flags & RTF_UP) == 0) {
229 errmsg = "interface down";
230 goto die;
231 }
232
233 linkstat =
234 LINK_STATE_IS_UP(ifm->ifm_data.ifi_link_state) ? 1 : 0;
235 if (linkstat != ifi->linkstat) {
236 #ifdef DEBUG
237 debug("link state %s -> %s",
238 ifi->linkstat ? "up" : "down",
239 linkstat ? "up" : "down");
240 #endif
241 ifi->linkstat = interface_status(ifi->name);
242 if (ifi->linkstat) {
243 client->state = S_REBOOTING;
244 state_reboot();
245 }
246 }
247 break;
248 case RTM_IFANNOUNCE:
249 ifan = (struct if_announcemsghdr *)rtm;
250 if (ifan->ifan_what == IFAN_DEPARTURE &&
251 ifan->ifan_index == ifi->index) {
252 errmsg = "interface departure";
253 goto die;
254 }
255 break;
256 default:
257 break;
258 }
259 return;
260
261 die:
262 script_init("FAIL");
263 script_go();
264 error("routehandler: %s", errmsg);
265 }
266
267 int
268 main(int argc, char *argv[])
269 {
270 int ch, fd;
271 int pipe_fd[2];
272 int quiet = 0;
273 int dokillclient = 0;
274 int i;
275 struct passwd *pw;
276
277 /* Initially, log errors to stderr as well as to syslogd. */
278 openlog(getprogname(), LOG_PID | LOG_NDELAY, DHCPD_LOG_FACILITY);
279 setlogmask(LOG_UPTO(LOG_INFO));
280
281 signal(SIGINT, sig_handle);
282 signal(SIGHUP, sig_handle);
283
284 while ((ch = getopt(argc, argv, "c:dl:quwx")) != -1) {
285 switch (ch) {
286 case 'c':
287 path_dhclient_conf = optarg;
288 break;
289 case 'd':
290 no_daemon = 1;
291 break;
292 case 'l':
293 path_dhclient_db = optarg;
294 break;
295 case 'q':
296 quiet = 1;
297 break;
298 case 'u':
299 unknown_ok = 0;
300 break;
301 case 'w':
302 stayalive = 1;
303 break;
304 case 'x':
305 dokillclient = 1;
306 break;
307 default:
308 usage();
309 }
310 }
311
312 argc -= optind;
313 argv += optind;
314
315 if (argc != 1)
316 usage();
317 orig_ifname = argv[0];
318
319 if (dokillclient) {
320 char buf[256];
321
322 snprintf(buf, sizeof(buf),
323 "/var/run/dhclient.%s.pid", orig_ifname);
324 fd = open(buf, O_RDWR, 0644);
325 if (fd < 0 || killclient(fd)) {
326 fprintf(stderr,
327 "no dhclient running on %s\n",
328 orig_ifname);
329 } else {
330 fprintf(stderr,
331 "stopping dhclient on %s\n",
332 orig_ifname);
333 }
334 if (fd >= 0)
335 close(fd);
336 exit(1);
337 }
338
339 if ((nullfd = open(_PATH_DEVNULL, O_RDWR, 0)) == -1)
340 error("cannot open %s: %m", _PATH_DEVNULL);
341
342 /*
343 * If asked to stay alive forever get our daemon going right now
344 * Then set up to fork/monitor and refork on exit.
345 *
346 * When I say 'forever' I really mean it. If there are configuration
347 * problems or missing interfaces or whatever, dhclient will wait
348 * 10 seconds and try again.
349 */
350 if (stayalive) {
351 pid_t pid;
352 pid_t rpid;
353 int omask;
354
355 go_daemon();
356
357 for (;;) {
358 omask = sigblock(sigmask(SIGINT) | sigmask(SIGHUP));
359 pid = fork();
360 if (pid > 0)
361 monitor_pid = pid;
362 sigsetmask(omask);
363
364 if (pid == 0) /* child falls out of loop */
365 break;
366 while (pid > 0) {
367 rpid = waitpid(pid, NULL, 0);
368 if (rpid == pid)
369 break;
370 if (rpid != EINTR)
371 break;
372 }
373 sleep(10);
374 }
375 }
376
377 ifi = calloc(1, sizeof(*ifi));
378 if (ifi == NULL)
379 error("ifi calloc");
380 client = calloc(1, sizeof(*client));
381 if (client == NULL)
382 error("client calloc");
383 config = calloc(1, sizeof(*config));
384 if (config == NULL)
385 error("config calloc");
386
387 get_ifname(ifi->name, argv[0]);
388
389 if (path_dhclient_db == NULL && asprintf(&path_dhclient_db, "%s.%s",
390 _PATH_DHCLIENT_DB, ifi->name) == -1)
391 error("asprintf");
392
393 if (quiet)
394 log_perror = 0;
395
396 tzset();
397
398 memset(&sockaddr_broadcast, 0, sizeof(sockaddr_broadcast));
399 sockaddr_broadcast.sin_family = AF_INET;
400 sockaddr_broadcast.sin_port = htons(REMOTE_PORT);
401 sockaddr_broadcast.sin_addr.s_addr = INADDR_BROADCAST;
402 sockaddr_broadcast.sin_len = sizeof(sockaddr_broadcast);
403 inaddr_any.s_addr = INADDR_ANY;
404
405 read_client_conf();
406
407 if (interface_status(ifi->name) == 0) {
408 interface_link_forceup(ifi->name);
409 /* Give it up to 4 seconds of silent grace to find link */
410 i = -4;
411 } else {
412 i = 0;
413 }
414
415 while (!(ifi->linkstat = interface_status(ifi->name))) {
416 if (i == 0)
417 fprintf(stderr, "%s: no link ...", ifi->name);
418 else if (i > 0)
419 fprintf(stderr, ".");
420 fflush(stderr);
421 if (++i > config->link_timeout) {
422 fprintf(stderr, " sleeping\n");
423 goto dispatch;
424 }
425 sleep(1);
426 }
427 if (i > 0)
428 fprintf(stderr, " got link\n");
429
430 dispatch:
431 if ((pw = getpwnam("_dhcp")) == NULL)
432 error("no such user: _dhcp");
433
434 if (pipe(pipe_fd) == -1)
435 error("pipe");
436
437 go_daemon();
438 fork_privchld(pipe_fd[0], pipe_fd[1]);
439
440 close(pipe_fd[0]);
441 privfd = pipe_fd[1];
442
443 if ((fd = open(path_dhclient_db, O_RDONLY|O_EXLOCK|O_CREAT, 0)) == -1)
444 error("can't open and lock %s: %m", path_dhclient_db);
445 read_client_leases();
446 if ((leaseFile = fopen(path_dhclient_db, "w")) == NULL)
447 error("can't open %s: %m", path_dhclient_db);
448 rewrite_client_leases();
449 close(fd);
450
451 if ((routefd = socket(PF_ROUTE, SOCK_RAW, 0)) == -1)
452 error("socket(PF_ROUTE, SOCK_RAW): %m");
453
454 /* set up the interface */
455 discover_interface();
456
457 if (chroot(_PATH_VAREMPTY) == -1)
458 error("chroot");
459 if (chdir("/") == -1)
460 error("chdir(\"/\")");
461
462 if (setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) == -1)
463 error("setresgid");
464 if (setgroups(1, &pw->pw_gid) == -1)
465 error("setgroups");
466 if (setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid) == -1)
467 error("setresuid");
468
469 endpwent();
470
471 setproctitle("%s", ifi->name);
472
473 if (ifi->linkstat) {
474 client->state = S_REBOOTING;
475 state_reboot();
476 }
477 dispatch();
478
479 /* not reached */
480 return (0);
481 }
482
483 void
484 usage(void)
485 {
486 fprintf(stderr, "usage: %s [-dqu] [-c file] [-l file] interface\n",
487 getprogname());
488 exit(1);
489 }
490
491 /*
492 * Individual States:
493 *
494 * Each routine is called from the dhclient_state_machine() in one of
495 * these conditions:
496 * -> entering INIT state
497 * -> recvpacket_flag == 0: timeout in this state
498 * -> otherwise: received a packet in this state
499 *
500 * Return conditions as handled by dhclient_state_machine():
501 * Returns 1, sendpacket_flag = 1: send packet, reset timer.
502 * Returns 1, sendpacket_flag = 0: just reset the timer (wait for a milestone).
503 * Returns 0: finish the nap which was interrupted for no good reason.
504 *
505 * Several per-interface variables are used to keep track of the process:
506 * active_lease: the lease that is being used on the interface
507 * (null pointer if not configured yet).
508 * offered_leases: leases corresponding to DHCPOFFER messages that have
509 * been sent to us by DHCP servers.
510 * acked_leases: leases corresponding to DHCPACK messages that have been
511 * sent to us by DHCP servers.
512 * sendpacket: DHCP packet we're trying to send.
513 * destination: IP address to send sendpacket to
514 * In addition, there are several relevant per-lease variables.
515 * T1_expiry, T2_expiry, lease_expiry: lease milestones
516 * In the active lease, these control the process of renewing the lease;
517 * In leases on the acked_leases list, this simply determines when we
518 * can no longer legitimately use the lease.
519 */
520 void
521 state_reboot(void)
522 {
523 /* Cancel all timeouts, since a link state change gets us here
524 and can happen anytime. */
525 cancel_timeout();
526
527 /* If we don't remember an active lease, go straight to INIT. */
528 if (!client->active || client->active->is_bootp) {
529 client->state = S_INIT;
530 state_init();
531 return;
532 }
533
534 /* make_request doesn't initialize xid because it normally comes
535 from the DHCPDISCOVER, but we haven't sent a DHCPDISCOVER,
536 so pick an xid now. */
537 client->xid = arc4random();
538
539 /* Make a DHCPREQUEST packet, and set appropriate per-interface
540 flags. */
541 make_request(client->active);
542 client->destination = iaddr_broadcast;
543 client->first_sending = time(NULL);
544 client->interval = 0;
545
546 send_request();
547 }
548
549 /*
550 * Called when a lease has completely expired and we've
551 * been unable to renew it.
552 */
553 void
554 state_init(void)
555 {
556 /* Make a DHCPDISCOVER packet, and set appropriate per-interface
557 flags. */
558 make_discover(client->active);
559 client->xid = client->packet.xid;
560 client->destination = iaddr_broadcast;
561 client->state = S_SELECTING;
562 client->first_sending = time(NULL);
563 client->interval = 0;
564
565 send_discover();
566 }
567
568 /*
569 * state_selecting is called when one or more DHCPOFFER packets
570 * have been received and a configurable period of time has passed.
571 */
572 void
573 state_selecting(void)
574 {
575 struct client_lease *lp, *next, *picked;
576 time_t cur_time;
577
578 /* Cancel state_selecting and send_discover timeouts, since either
579 one could have got us here. */
580 cancel_timeout();
581
582 /* We have received one or more DHCPOFFER packets. Currently,
583 the only criterion by which we judge leases is whether or
584 not we get a response when we arp for them. */
585 picked = NULL;
586 for (lp = client->offered_leases; lp; lp = next) {
587 next = lp->next;
588
589 if (!picked) {
590 picked = lp;
591 } else {
592 make_decline(lp);
593 send_decline();
594 free_client_lease(lp);
595 }
596 }
597 client->offered_leases = NULL;
598
599 /* If we just tossed all the leases we were offered, go back
600 to square one. */
601 if (!picked) {
602 client->state = S_INIT;
603 state_init();
604 return;
605 }
606 picked->next = NULL;
607
608 time(&cur_time);
609
610 /* If it was a BOOTREPLY, we can just take the address right now. */
611 if (!picked->options[DHO_DHCP_MESSAGE_TYPE].len) {
612 client->new = picked;
613
614 /* Make up some lease expiry times
615 XXX these should be configurable. */
616 client->new->expiry = cur_time + 12000;
617 client->new->renewal += cur_time + 8000;
618 client->new->rebind += cur_time + 10000;
619
620 client->state = S_REQUESTING;
621
622 /* Bind to the address we received. */
623 bind_lease();
624 return;
625 }
626
627 /* Go to the REQUESTING state. */
628 client->destination = iaddr_broadcast;
629 client->state = S_REQUESTING;
630 client->first_sending = cur_time;
631 client->interval = 0;
632
633 /* Make a DHCPREQUEST packet from the lease we picked. */
634 make_request(picked);
635 client->xid = client->packet.xid;
636
637 /* Toss the lease we picked - we'll get it back in a DHCPACK. */
638 free_client_lease(picked);
639
640 send_request();
641 }
642
643 void
644 dhcpack(struct iaddr client_addr, struct option_data *options)
645 {
646 struct client_lease *lease;
647 time_t cur_time;
648
649
650 if (client->state != S_REBOOTING &&
651 client->state != S_REQUESTING &&
652 client->state != S_RENEWING &&
653 client->state != S_REBINDING)
654 return;
655
656
657 lease = packet_to_lease(options);
658 if (!lease) {
659 note("packet_to_lease failed.");
660 return;
661 }
662
663 client->new = lease;
664
665 /* Stop resending DHCPREQUEST. */
666 cancel_timeout();
667
668 /* Figure out the lease time. */
669 if (client->new->options[DHO_DHCP_LEASE_TIME].data)
670 client->new->expiry =
671 getULong(client->new->options[DHO_DHCP_LEASE_TIME].data);
672 else
673 client->new->expiry = DEFAULT_LEASE_TIME;
674 /* A number that looks negative here is really just very large,
675 because the lease expiry offset is unsigned. */
676 if (client->new->expiry < 0)
677 client->new->expiry = TIME_MAX;
678 /* XXX should be fixed by resetting the client state */
679 if (client->new->expiry < 60)
680 client->new->expiry = 60;
681
682 /* Take the server-provided renewal time if there is one;
683 otherwise figure it out according to the spec. */
684 if (client->new->options[DHO_DHCP_RENEWAL_TIME].len)
685 client->new->renewal =
686 getULong(client->new->options[DHO_DHCP_RENEWAL_TIME].data);
687 else
688 client->new->renewal = client->new->expiry / 2;
689
690 /* Same deal with the rebind time. */
691 if (client->new->options[DHO_DHCP_REBINDING_TIME].len)
692 client->new->rebind =
693 getULong(client->new->options[DHO_DHCP_REBINDING_TIME].data);
694 else
695 client->new->rebind = client->new->renewal +
696 client->new->renewal / 2 + client->new->renewal / 4;
697
698 time(&cur_time);
699
700 client->new->expiry += cur_time;
701 /* Lease lengths can never be negative. */
702 if (client->new->expiry < cur_time)
703 client->new->expiry = TIME_MAX;
704 client->new->renewal += cur_time;
705 if (client->new->renewal < cur_time)
706 client->new->renewal = TIME_MAX;
707 client->new->rebind += cur_time;
708 if (client->new->rebind < cur_time)
709 client->new->rebind = TIME_MAX;
710
711 bind_lease();
712 }
713
714 void
715 bind_lease(void)
716 {
717 /* Run the client script with the new parameters. */
718 script_init((client->state == S_REQUESTING ? "BOUND" :
719 (client->state == S_RENEWING ? "RENEW" :
720 (client->state == S_REBOOTING ? "REBOOT" : "REBIND"))));
721 if (client->active && client->state != S_REBOOTING)
722 script_write_params("old_", client->active);
723 script_write_params("new_", client->new);
724 script_go();
725
726 /* Replace the old active lease with the new one. */
727 if (client->active)
728 free_client_lease(client->active);
729 client->active = client->new;
730 client->new = NULL;
731
732 /* Write out new leases file. */
733 rewrite_client_leases();
734
735 /* Set timeout to start the renewal process. */
736 set_timeout(client->active->renewal, state_bound);
737
738 note("bound to %s -- renewal in %lld seconds.",
739 piaddr(client->active->address),
740 (long long)(client->active->renewal - time(NULL)));
741 client->state = S_BOUND;
742 }
743
744 /*
745 * state_bound is called when we've successfully bound to a particular
746 * lease, but the renewal time on that lease has expired. We are
747 * expected to unicast a DHCPREQUEST to the server that gave us our
748 * original lease.
749 */
750 void
751 state_bound(void)
752 {
753 /* T1 has expired. */
754 make_request(client->active);
755 client->xid = client->packet.xid;
756
757 if (client->active->options[DHO_DHCP_SERVER_IDENTIFIER].len == 4) {
758 memcpy(client->destination.iabuf,
759 client->active->options[DHO_DHCP_SERVER_IDENTIFIER].data,
760 4);
761 client->destination.len = 4;
762 } else
763 client->destination = iaddr_broadcast;
764
765 client->first_sending = time(NULL);
766 client->interval = 0;
767 client->state = S_RENEWING;
768
769 send_request();
770 }
771
772 void
773 dhcpoffer(struct iaddr client_addr, struct option_data *options)
774 {
775 struct client_lease *lease, *lp;
776 int i;
777 time_t stop_selecting;
778 char *name = options[DHO_DHCP_MESSAGE_TYPE].len ? "DHCPOFFER" :
779 "BOOTREPLY";
780
781
782 if (client->state != S_SELECTING)
783 return;
784
785
786 /* If this lease doesn't supply the minimum required parameters,
787 blow it off. */
788 for (i = 0; config->required_options[i]; i++) {
789 if (!options[config->required_options[i]].len) {
790 note("%s isn't satisfactory.", name);
791 return;
792 }
793 }
794
795 /* If we've already seen this lease, don't record it again. */
796 for (lease = client->offered_leases;
797 lease; lease = lease->next) {
798 if (lease->address.len == sizeof(client->packet.yiaddr) &&
799 !memcmp(lease->address.iabuf,
800 &client->packet.yiaddr, lease->address.len)) {
801 #ifdef DEBUG
802 debug("%s already seen.", name);
803 #endif
804 return;
805 }
806 }
807
808 lease = packet_to_lease(options);
809 if (!lease) {
810 note("packet_to_lease failed.");
811 return;
812 }
813
814 /*
815 * Reject offers whose subnet is already configured on another
816 * interface.
817 */
818 if (subnet_exists(lease))
819 return;
820
821 /* If this lease was acquired through a BOOTREPLY, record that
822 fact. */
823 if (!options[DHO_DHCP_MESSAGE_TYPE].len)
824 lease->is_bootp = 1;
825
826 /* Figure out when we're supposed to stop selecting. */
827 stop_selecting = client->first_sending + config->select_interval;
828
829 /* If this is the lease we asked for, put it at the head of the
830 list, and don't mess with the arp request timeout. */
831 if (addr_eq(lease->address, client->requested_address)) {
832 lease->next = client->offered_leases;
833 client->offered_leases = lease;
834 } else {
835 /* Put the lease at the end of the list. */
836 lease->next = NULL;
837 if (!client->offered_leases)
838 client->offered_leases = lease;
839 else {
840 for (lp = client->offered_leases; lp->next;
841 lp = lp->next)
842 ; /* nothing */
843 lp->next = lease;
844 }
845 }
846
847 /* If the selecting interval has expired, go immediately to
848 state_selecting(). Otherwise, time out into
849 state_selecting at the select interval. */
850 if (stop_selecting <= time(NULL))
851 state_selecting();
852 else {
853 set_timeout(stop_selecting, state_selecting);
854 }
855 }
856
857 /*
858 * Allocate a client_lease structure and initialize it from the
859 * parameters in the specified packet.
860 */
861 struct client_lease *
862 packet_to_lease(struct option_data *options)
863 {
864 struct client_lease *lease;
865 int i;
866
867 lease = malloc(sizeof(struct client_lease));
868
869 if (!lease) {
870 warning("dhcpoffer: no memory to record lease.");
871 return (NULL);
872 }
873
874 memset(lease, 0, sizeof(*lease));
875
876 /* Copy the lease options. */
877 for (i = 0; i < 256; i++) {
878 if (options[i].len) {
879 lease->options[i] = options[i];
880 options[i].data = NULL;
881 options[i].len = 0;
882 if (!check_option(lease, i)) {
883 warning("Invalid lease option - ignoring offer");
884 free_client_lease(lease);
885 return (NULL);
886 }
887 }
888 }
889
890 lease->address.len = sizeof(client->packet.yiaddr);
891 memcpy(lease->address.iabuf, &client->packet.yiaddr,
892 lease->address.len);
893
894 /* If the server name was filled out, copy it. */
895 if ((!lease->options[DHO_DHCP_OPTION_OVERLOAD].len ||
896 !(lease->options[DHO_DHCP_OPTION_OVERLOAD].data[0] & 2)) &&
897 client->packet.sname[0]) {
898 lease->server_name = malloc(DHCP_SNAME_LEN + 1);
899 if (!lease->server_name) {
900 warning("dhcpoffer: no memory for server name.");
901 free_client_lease(lease);
902 return (NULL);
903 }
904 memcpy(lease->server_name, client->packet.sname,
905 DHCP_SNAME_LEN);
906 lease->server_name[DHCP_SNAME_LEN] = '\0';
907 if (!res_hnok(lease->server_name)) {
908 warning("Bogus server name %s", lease->server_name);
909 free(lease->server_name);
910 lease->server_name = NULL;
911 }
912 }
913
914 /* Ditto for the filename. */
915 if ((!lease->options[DHO_DHCP_OPTION_OVERLOAD].len ||
916 !(lease->options[DHO_DHCP_OPTION_OVERLOAD].data[0] & 1)) &&
917 client->packet.file[0]) {
918 /* Don't count on the NUL terminator. */
919 lease->filename = malloc(DHCP_FILE_LEN + 1);
920 if (!lease->filename) {
921 warning("dhcpoffer: no memory for filename.");
922 free_client_lease(lease);
923 return (NULL);
924 }
925 memcpy(lease->filename, client->packet.file, DHCP_FILE_LEN);
926 lease->filename[DHCP_FILE_LEN] = '\0';
927 }
928 return lease;
929 }
930
931 void
932 dhcpnak(struct iaddr client_addr, struct option_data *options)
933 {
934
935 if (client->state != S_REBOOTING &&
936 client->state != S_REQUESTING &&
937 client->state != S_RENEWING &&
938 client->state != S_REBINDING)
939 return;
940
941
942 if (!client->active) {
943 note("DHCPNAK with no active lease.");
944 return;
945 }
946
947 free_client_lease(client->active);
948 client->active = NULL;
949
950 /* Stop sending DHCPREQUEST packets... */
951 cancel_timeout();
952
953 client->state = S_INIT;
954 state_init();
955 }
956
957 /*
958 * Send out a DHCPDISCOVER packet, and set a timeout to send out another
959 * one after the right interval has expired. If we don't get an offer by
960 * the time we reach the panic interval, call the panic function.
961 */
962 void
963 send_discover(void)
964 {
965 time_t cur_time;
966 int interval, increase = 1;
967
968 time(&cur_time);
969
970 /* Figure out how long it's been since we started transmitting. */
971 interval = cur_time - client->first_sending;
972
973 /* If we're past the panic timeout, call the script and tell it
974 we haven't found anything for this interface yet. */
975 if (interval > config->timeout) {
976 state_panic();
977 return;
978 }
979
980 /*
981 * If we're supposed to increase the interval, do so. If it's
982 * currently zero (i.e., we haven't sent any packets yet), set
983 * it to initial_interval; otherwise, add to it a random
984 * number between zero and two times itself. On average, this
985 * means that it will double with every transmission.
986 */
987 if (increase) {
988 if (!client->interval)
989 client->interval = config->initial_interval;
990 else {
991 client->interval += (arc4random() >> 2) %
992 (2 * client->interval);
993 }
994
995 /* Don't backoff past cutoff. */
996 if (client->interval > config->backoff_cutoff)
997 client->interval = ((config->backoff_cutoff / 2)
998 + ((arc4random() >> 2) %
999 config->backoff_cutoff));
1000 } else if (!client->interval)
1001 client->interval = config->initial_interval;
1002
1003 /* If the backoff would take us to the panic timeout, just use that
1004 as the interval. */
1005 if (cur_time + client->interval >
1006 client->first_sending + config->timeout)
1007 client->interval = (client->first_sending +
1008 config->timeout) - cur_time + 1;
1009
1010 /* Record the number of seconds since we started sending. */
1011 if (interval < 65536)
1012 client->packet.secs = htons(interval);
1013 else
1014 client->packet.secs = htons(65535);
1015 client->secs = client->packet.secs;
1016
1017 note("DHCPDISCOVER on %s to %s port %d interval %ld",
1018 ifi->name, inet_ntoa(sockaddr_broadcast.sin_addr),
1019 ntohs(sockaddr_broadcast.sin_port), client->interval);
1020
1021 send_packet(inaddr_any, &sockaddr_broadcast, NULL);
1022
1023 set_timeout_interval(client->interval, send_discover);
1024 }
1025
1026 /*
1027 * state_panic gets called if we haven't received any offers in a preset
1028 * amount of time. When this happens, we try to use existing leases
1029 * that haven't yet expired, and failing that, we call the client script
1030 * and hope it can do something.
1031 */
1032 void
1033 state_panic(void)
1034 {
1035 struct client_lease *loop = client->active;
1036 struct client_lease *lp;
1037 time_t cur_time;
1038
1039 note("No DHCPOFFERS received.");
1040
1041 /* We may not have an active lease, but we may have some
1042 predefined leases that we can try. */
1043 if (!client->active && client->leases)
1044 goto activate_next;
1045
1046 /* Run through the list of leases and see if one can be used. */
1047 time(&cur_time);
1048 while (client->active) {
1049 if (client->active->expiry > cur_time) {
1050 note("Trying recorded lease %s",
1051 piaddr(client->active->address));
1052 /* Run the client script with the existing
1053 parameters. */
1054 script_init("TIMEOUT");
1055 script_write_params("new_", client->active);
1056
1057 /* If the old lease is still good and doesn't
1058 yet need renewal, go into BOUND state and
1059 timeout at the renewal time. */
1060 if (!script_go()) {
1061 if (cur_time < client->active->renewal) {
1062 client->state = S_BOUND;
1063 note("bound: renewal in %lld seconds.",
1064 (long long)(client->active->renewal
1065 - cur_time));
1066 set_timeout(client->active->renewal,
1067 state_bound);
1068 } else {
1069 client->state = S_BOUND;
1070 note("bound: immediate renewal.");
1071 state_bound();
1072 }
1073 return;
1074 }
1075 }
1076
1077 /* If there are no other leases, give up. */
1078 if (!client->leases) {
1079 client->leases = client->active;
1080 client->active = NULL;
1081 break;
1082 }
1083
1084 activate_next:
1085 /* Otherwise, put the active lease at the end of the
1086 lease list, and try another lease.. */
1087 for (lp = client->leases; lp->next; lp = lp->next)
1088 ;
1089 lp->next = client->active;
1090 if (lp->next)
1091 lp->next->next = NULL;
1092 client->active = client->leases;
1093 client->leases = client->leases->next;
1094
1095 /* If we already tried this lease, we've exhausted the
1096 set of leases, so we might as well give up for
1097 now. */
1098 if (client->active == loop)
1099 break;
1100 else if (!loop)
1101 loop = client->active;
1102 }
1103
1104 /* No leases were available, or what was available didn't work, so
1105 tell the shell script that we failed to allocate an address,
1106 and try again later. */
1107 note("No working leases in persistent database - sleeping.");
1108 script_init("FAIL");
1109 script_go();
1110 client->state = S_INIT;
1111 set_timeout_interval(config->retry_interval, state_init);
1112 }
1113
1114 void
1115 send_request(void)
1116 {
1117 struct sockaddr_in destination;
1118 struct in_addr from;
1119 time_t cur_time;
1120 int interval;
1121
1122 time(&cur_time);
1123
1124 /* Figure out how long it's been since we started transmitting. */
1125 interval = (int)(cur_time - client->first_sending);
1126
1127 /* If we're in the INIT-REBOOT or REQUESTING state and we're
1128 past the reboot timeout, go to INIT and see if we can
1129 DISCOVER an address... */
1130 /* XXX In the INIT-REBOOT state, if we don't get an ACK, it
1131 means either that we're on a network with no DHCP server,
1132 or that our server is down. In the latter case, assuming
1133 that there is a backup DHCP server, DHCPDISCOVER will get
1134 us a new address, but we could also have successfully
1135 reused our old address. In the former case, we're hosed
1136 anyway. This is not a win-prone situation. */
1137 if ((client->state == S_REBOOTING ||
1138 client->state == S_REQUESTING) &&
1139 interval > config->reboot_timeout) {
1140 client->state = S_INIT;
1141 cancel_timeout();
1142 state_init();
1143 return;
1144 }
1145
1146 /* If the lease has expired, relinquish the address and go back
1147 to the INIT state. */
1148 if (client->state != S_REQUESTING &&
1149 cur_time > client->active->expiry) {
1150 /* Run the client script with the new parameters. */
1151 script_init("EXPIRE");
1152 script_write_params("old_", client->active);
1153 script_go();
1154
1155 client->state = S_INIT;
1156 state_init();
1157 return;
1158 }
1159
1160 /* Do the exponential backoff... */
1161 if (!client->interval)
1162 client->interval = config->initial_interval;
1163 else
1164 client->interval += ((arc4random() >> 2) %
1165 (2 * client->interval));
1166
1167 /* Don't backoff past cutoff. */
1168 if (client->interval > config->backoff_cutoff)
1169 client->interval = ((config->backoff_cutoff / 2) +
1170 ((arc4random() >> 2) % client->interval));
1171
1172 /* If the backoff would take us to the expiry time, just set the
1173 timeout to the expiry time. */
1174 if (client->state != S_REQUESTING && cur_time + client->interval >
1175 client->active->expiry)
1176 client->interval = client->active->expiry - cur_time + 1;
1177
1178 /* If the lease T2 time has elapsed, or if we're not yet bound,
1179 broadcast the DHCPREQUEST rather than unicasting. */
1180 memset(&destination, 0, sizeof(destination));
1181 if (client->state == S_REQUESTING ||
1182 client->state == S_REBOOTING ||
1183 cur_time > client->active->rebind)
1184 destination.sin_addr.s_addr = INADDR_BROADCAST;
1185 else
1186 memcpy(&destination.sin_addr.s_addr, client->destination.iabuf,
1187 sizeof(destination.sin_addr.s_addr));
1188 destination.sin_port = htons(REMOTE_PORT);
1189 destination.sin_family = AF_INET;
1190 destination.sin_len = sizeof(destination);
1191
1192 if (client->state != S_REQUESTING)
1193 memcpy(&from, client->active->address.iabuf, sizeof(from));
1194 else
1195 from.s_addr = INADDR_ANY;
1196
1197 /* Record the number of seconds since we started sending. */
1198 if (client->state == S_REQUESTING)
1199 client->packet.secs = client->secs;
1200 else {
1201 if (interval < 65536)
1202 client->packet.secs = htons(interval);
1203 else
1204 client->packet.secs = htons(65535);
1205 }
1206
1207 note("DHCPREQUEST on %s to %s port %d", ifi->name,
1208 inet_ntoa(destination.sin_addr), ntohs(destination.sin_port));
1209
1210 send_packet(from, &destination, NULL);
1211
1212 set_timeout_interval(client->interval, send_request);
1213 }
1214
1215 void
1216 send_decline(void)
1217 {
1218 note("DHCPDECLINE on %s to %s port %d", ifi->name,
1219 inet_ntoa(sockaddr_broadcast.sin_addr),
1220 ntohs(sockaddr_broadcast.sin_port));
1221
1222 send_packet(inaddr_any, &sockaddr_broadcast, NULL);
1223 }
1224
1225 void
1226 make_discover(struct client_lease *lease)
1227 {
1228 unsigned char discover = DHCPDISCOVER;
1229 struct option_data options[256];
1230 int i;
1231
1232 memset(options, 0, sizeof(options));
1233 memset(&client->packet, 0, sizeof(client->packet));
1234
1235 /* Set DHCP_MESSAGE_TYPE to DHCPDISCOVER */
1236 i = DHO_DHCP_MESSAGE_TYPE;
1237 options[i].data = &discover;
1238 options[i].len = sizeof(discover);
1239
1240 /* Request the options we want */
1241 i = DHO_DHCP_PARAMETER_REQUEST_LIST;
1242 options[i].data = config->requested_options;
1243 options[i].len = config->requested_option_count;
1244
1245 /* If we had an address, try to get it again. */
1246 if (lease) {
1247 client->requested_address = lease->address;
1248 i = DHO_DHCP_REQUESTED_ADDRESS;
1249 options[i].data = lease->address.iabuf;
1250 options[i].len = lease->address.len;
1251 } else
1252 client->requested_address.len = 0;
1253
1254 /* Send any options requested in the config file. */
1255 for (i = 0; i < 256; i++)
1256 if (!options[i].data &&
1257 config->send_options[i].data) {
1258 options[i].data = config->send_options[i].data;
1259 options[i].len = config->send_options[i].len;
1260 }
1261
1262 /* Set up the option buffer to fit in a minimal UDP packet. */
1263 i = cons_options(options);
1264 if (i == -1 || client->packet.options[i] != DHO_END)
1265 error("options do not fit in DHCPDISCOVER packet.");
1266 client->packet_length = DHCP_FIXED_NON_UDP+i+1;
1267 if (client->packet_length < BOOTP_MIN_LEN)
1268 client->packet_length = BOOTP_MIN_LEN;
1269
1270 client->packet.op = BOOTREQUEST;
1271 client->packet.htype = ifi->hw_address.htype;
1272 client->packet.hlen = ifi->hw_address.hlen;
1273 client->packet.hops = 0;
1274 client->packet.xid = arc4random();
1275 client->packet.secs = 0; /* filled in by send_discover. */
1276 client->packet.flags = 0;
1277
1278 memset(&client->packet.ciaddr, 0, sizeof(client->packet.ciaddr));
1279 memset(&client->packet.yiaddr, 0, sizeof(client->packet.yiaddr));
1280 memset(&client->packet.siaddr, 0, sizeof(client->packet.siaddr));
1281 memset(&client->packet.giaddr, 0, sizeof(client->packet.giaddr));
1282 memcpy(client->packet.chaddr, ifi->hw_address.haddr,
1283 ifi->hw_address.hlen);
1284 }
1285
1286 void
1287 make_request(struct client_lease * lease)
1288 {
1289 unsigned char request = DHCPREQUEST;
1290 struct option_data options[256];
1291 int i;
1292
1293 memset(options, 0, sizeof(options));
1294 memset(&client->packet, 0, sizeof(client->packet));
1295
1296 /* Set DHCP_MESSAGE_TYPE to DHCPREQUEST */
1297 i = DHO_DHCP_MESSAGE_TYPE;
1298 options[i].data = &request;
1299 options[i].len = sizeof(request);
1300
1301 /* Request the options we want */
1302 i = DHO_DHCP_PARAMETER_REQUEST_LIST;
1303 options[i].data = config->requested_options;
1304 options[i].len = config->requested_option_count;
1305
1306 /* If we are requesting an address that hasn't yet been assigned
1307 to us, use the DHCP Requested Address option. */
1308 if (client->state == S_REQUESTING) {
1309 /* Send back the server identifier... */
1310 i = DHO_DHCP_SERVER_IDENTIFIER;
1311 options[i].data = lease->options[i].data;
1312 options[i].len = lease->options[i].len;
1313 }
1314 if (client->state == S_REQUESTING ||
1315 client->state == S_REBOOTING) {
1316 client->requested_address = lease->address;
1317 i = DHO_DHCP_REQUESTED_ADDRESS;
1318 options[i].data = lease->address.iabuf;
1319 options[i].len = lease->address.len;
1320 } else
1321 client->requested_address.len = 0;
1322
1323 /* Send any options requested in the config file. */
1324 for (i = 0; i < 256; i++)
1325 if (!options[i].data && config->send_options[i].data) {
1326 options[i].data = config->send_options[i].data;
1327 options[i].len = config->send_options[i].len;
1328 }
1329
1330 /* Set up the option buffer to fit in a minimal UDP packet. */
1331 i = cons_options(options);
1332 if (i == -1 || client->packet.options[i] != DHO_END)
1333 error("options do not fit in DHCPREQUEST packet.");
1334 client->packet_length = DHCP_FIXED_NON_UDP+i+1;
1335 if (client->packet_length < BOOTP_MIN_LEN)
1336 client->packet_length = BOOTP_MIN_LEN;
1337
1338 client->packet.op = BOOTREQUEST;
1339 client->packet.htype = ifi->hw_address.htype;
1340 client->packet.hlen = ifi->hw_address.hlen;
1341 client->packet.hops = 0;
1342 client->packet.xid = client->xid;
1343 client->packet.secs = 0; /* Filled in by send_request. */
1344 client->packet.flags = 0;
1345
1346 /* If we own the address we're requesting, put it in ciaddr;
1347 otherwise set ciaddr to zero. */
1348 if (client->state == S_BOUND ||
1349 client->state == S_RENEWING ||
1350 client->state == S_REBINDING) {
1351 memcpy(&client->packet.ciaddr,
1352 lease->address.iabuf, lease->address.len);
1353 } else {
1354 memset(&client->packet.ciaddr, 0,
1355 sizeof(client->packet.ciaddr));
1356 }
1357
1358 memset(&client->packet.yiaddr, 0, sizeof(client->packet.yiaddr));
1359 memset(&client->packet.siaddr, 0, sizeof(client->packet.siaddr));
1360 memset(&client->packet.giaddr, 0, sizeof(client->packet.giaddr));
1361 memcpy(client->packet.chaddr, ifi->hw_address.haddr,
1362 ifi->hw_address.hlen);
1363 }
1364
1365 void
1366 make_decline(struct client_lease *lease)
1367 {
1368 struct option_data options[256];
1369 unsigned char decline = DHCPDECLINE;
1370 int i;
1371
1372 memset(options, 0, sizeof(options));
1373 memset(&client->packet, 0, sizeof(client->packet));
1374
1375 /* Set DHCP_MESSAGE_TYPE to DHCPDECLINE */
1376 i = DHO_DHCP_MESSAGE_TYPE;
1377 options[i].data = &decline;
1378 options[i].len = sizeof(decline);
1379
1380 /* Send back the server identifier... */
1381 i = DHO_DHCP_SERVER_IDENTIFIER;
1382 options[i].data = lease->options[i].data;
1383 options[i].len = lease->options[i].len;
1384
1385 /* Send back the address we're declining. */
1386 i = DHO_DHCP_REQUESTED_ADDRESS;
1387 options[i].data = lease->address.iabuf;
1388 options[i].len = lease->address.len;
1389
1390 /* Send the uid if the user supplied one. */
1391 i = DHO_DHCP_CLIENT_IDENTIFIER;
1392 if (config->send_options[i].len) {
1393 options[i].data = config->send_options[i].data;
1394 options[i].len = config->send_options[i].len;
1395 }
1396
1397 /* Set up the option buffer to fit in a minimal UDP packet. */
1398 i = cons_options(options);
1399 if (i == -1 || client->packet.options[i] != DHO_END)
1400 error("options do not fit in DHCPDECLINE packet.");
1401 client->packet_length = DHCP_FIXED_NON_UDP+i+1;
1402 if (client->packet_length < BOOTP_MIN_LEN)
1403 client->packet_length = BOOTP_MIN_LEN;
1404
1405 client->packet.op = BOOTREQUEST;
1406 client->packet.htype = ifi->hw_address.htype;
1407 client->packet.hlen = ifi->hw_address.hlen;
1408 client->packet.hops = 0;
1409 client->packet.xid = client->xid;
1410 client->packet.secs = 0; /* Filled in by send_request. */
1411 client->packet.flags = 0;
1412
1413 /* ciaddr must always be zero. */
1414 memset(&client->packet.ciaddr, 0, sizeof(client->packet.ciaddr));
1415 memset(&client->packet.yiaddr, 0, sizeof(client->packet.yiaddr));
1416 memset(&client->packet.siaddr, 0, sizeof(client->packet.siaddr));
1417 memset(&client->packet.giaddr, 0, sizeof(client->packet.giaddr));
1418 memcpy(client->packet.chaddr, ifi->hw_address.haddr,
1419 ifi->hw_address.hlen);
1420 }
1421
1422 void
1423 free_client_lease(struct client_lease *lease)
1424 {
1425 int i;
1426
1427 if (lease->server_name)
1428 free(lease->server_name);
1429 if (lease->filename)
1430 free(lease->filename);
1431 for (i = 0; i < 256; i++) {
1432 if (lease->options[i].len)
1433 free(lease->options[i].data);
1434 }
1435 free(lease);
1436 }
1437
1438 void
1439 rewrite_client_leases(void)
1440 {
1441 struct client_lease *lp;
1442
1443 if (!leaseFile) /* XXX */
1444 error("lease file not open");
1445
1446 fflush(leaseFile);
1447 rewind(leaseFile);
1448
1449 for (lp = client->leases; lp; lp = lp->next) {
1450 if (client->active && addr_eq(lp->address,
1451 client->active->address))
1452 continue;
1453 write_client_lease(lp);
1454 }
1455
1456 if (client->active)
1457 write_client_lease(client->active);
1458
1459 fflush(leaseFile);
1460 ftruncate(fileno(leaseFile), ftello(leaseFile));
1461 fsync(fileno(leaseFile));
1462 }
1463
1464 void
1465 write_client_lease(struct client_lease *lease)
1466 {
1467 struct tm *t;
1468 int i;
1469
1470 /* If the lease came from the config file, we don't need to stash
1471 a copy in the lease database. */
1472 if (lease->is_static)
1473 return;
1474
1475 if (!leaseFile) /* XXX */
1476 error("lease file not open");
1477
1478 fprintf(leaseFile, "lease {\n");
1479 if (lease->is_bootp)
1480 fprintf(leaseFile, " bootp;\n");
1481 fprintf(leaseFile, " interface \"%s\";\n", ifi->name);
1482 fprintf(leaseFile, " fixed-address %s;\n", piaddr(lease->address));
1483 if (lease->filename)
1484 fprintf(leaseFile, " filename \"%s\";\n", lease->filename);
1485 if (lease->server_name)
1486 fprintf(leaseFile, " server-name \"%s\";\n",
1487 lease->server_name);
1488 for (i = 0; i < 256; i++)
1489 if (lease->options[i].len)
1490 fprintf(leaseFile, " option %s %s;\n",
1491 dhcp_options[i].name,
1492 pretty_print_option(i, &lease->options[i], 1));
1493
1494 t = gmtime(&lease->renewal);
1495 fprintf(leaseFile, " renew %d %d/%d/%d %02d:%02d:%02d;\n",
1496 t->tm_wday, t->tm_year + 1900, t->tm_mon + 1, t->tm_mday,
1497 t->tm_hour, t->tm_min, t->tm_sec);
1498 t = gmtime(&lease->rebind);
1499 fprintf(leaseFile, " rebind %d %d/%d/%d %02d:%02d:%02d;\n",
1500 t->tm_wday, t->tm_year + 1900, t->tm_mon + 1, t->tm_mday,
1501 t->tm_hour, t->tm_min, t->tm_sec);
1502 t = gmtime(&lease->expiry);
1503 fprintf(leaseFile, " expire %d %d/%d/%d %02d:%02d:%02d;\n",
1504 t->tm_wday, t->tm_year + 1900, t->tm_mon + 1, t->tm_mday,
1505 t->tm_hour, t->tm_min, t->tm_sec);
1506 fprintf(leaseFile, "}\n");
1507 fflush(leaseFile);
1508 }
1509
1510 void
1511 script_init(char *reason)
1512 {
1513 size_t len;
1514 struct imsg_hdr hdr;
1515 struct buf *buf;
1516
1517 hdr.code = IMSG_SCRIPT_INIT;
1518 hdr.len = sizeof(struct imsg_hdr) + sizeof(size_t) + strlen(reason);
1519 buf = buf_open(hdr.len);
1520
1521 buf_add(buf, &hdr, sizeof(hdr));
1522 len = strlen(reason);
1523 buf_add(buf, &len, sizeof(len));
1524 buf_add(buf, reason, len);
1525
1526 buf_close(privfd, buf);
1527 }
1528
1529 void
1530 priv_script_init(char *reason)
1531 {
1532 client->scriptEnvsize = 100;
1533 if (client->scriptEnv == NULL)
1534 client->scriptEnv =
1535 calloc(client->scriptEnvsize, sizeof(char *));
1536 if (client->scriptEnv == NULL)
1537 error("script_init: no memory for environment");
1538
1539 client->scriptEnv[0] = strdup(CLIENT_PATH);
1540 if (client->scriptEnv[0] == NULL)
1541 error("script_init: no memory for environment");
1542
1543 client->scriptEnv[1] = NULL;
1544
1545 script_set_env("", "interface", ifi->name);
1546
1547 script_set_env("", "reason", reason);
1548 }
1549
1550 void
1551 priv_script_write_params(char *prefix, struct client_lease *lease)
1552 {
1553 char buf[256];
1554 struct option_data o;
1555 int i;
1556
1557 script_set_env(prefix, "ip_address", piaddr(lease->address));
1558
1559 if (lease->options[DHO_SUBNET_MASK].len &&
1560 (lease->options[DHO_SUBNET_MASK].len <
1561 sizeof(lease->address.iabuf))) {
1562 struct iaddr netmask, subnet, broadcast;
1563
1564 memcpy(netmask.iabuf, lease->options[DHO_SUBNET_MASK].data,
1565 lease->options[DHO_SUBNET_MASK].len);
1566 netmask.len = lease->options[DHO_SUBNET_MASK].len;
1567
1568 subnet = subnet_number(lease->address, netmask);
1569 if (subnet.len) {
1570 script_set_env(prefix, "network_number",
1571 piaddr(subnet));
1572 if (!lease->options[DHO_BROADCAST_ADDRESS].len) {
1573 broadcast = broadcast_addr(subnet, netmask);
1574 if (broadcast.len)
1575 script_set_env(prefix,
1576 "broadcast_address",
1577 piaddr(broadcast));
1578 }
1579 }
1580 }
1581
1582 if (lease->filename)
1583 script_set_env(prefix, "filename", lease->filename);
1584 if (lease->server_name)
1585 script_set_env(prefix, "server_name",
1586 lease->server_name);
1587
1588 for (i = 0; i < 256; i++) {
1589 if (!dhcp_option_ev_name(buf, sizeof(buf), &dhcp_options[i]))
1590 continue;
1591
1592 switch (config->default_actions[i]) {
1593 case ACTION_IGNORE:
1594 break;
1595
1596 case ACTION_DEFAULT:
1597 if (lease->options[i].len)
1598 script_set_env(prefix, buf,
1599 pretty_print_option(i, &lease->options[i],
1600 0));
1601 else if (config->defaults[i].len)
1602 script_set_env(prefix, buf,
1603 pretty_print_option(i, &config->defaults[i],
1604 0));
1605 break;
1606
1607 case ACTION_SUPERSEDE:
1608 if (config->defaults[i].len)
1609 script_set_env(prefix, buf,
1610 pretty_print_option(i, &config->defaults[i],
1611 0));
1612 break;
1613
1614 case ACTION_PREPEND:
1615 o.len = config->defaults[i].len + lease->options[i].len;
1616 if (o.len > 0) {
1617 o.data = calloc(1, o.len);
1618 if (o.data == NULL)
1619 error("no space to prepend '%s' to %s",
1620 config->defaults[i].data,
1621 dhcp_options[i].name);
1622 memcpy(o.data, config->defaults[i].data,
1623 config->defaults[i].len);
1624 memcpy(o.data + config->defaults[i].len,
1625 lease->options[i].data,
1626 lease->options[i].len);
1627 script_set_env(prefix, buf,
1628 pretty_print_option(i, &o, 0));
1629 free(o.data);
1630 }
1631 break;
1632
1633 case ACTION_APPEND:
1634 o.len = config->defaults[i].len + lease->options[i].len;
1635 if (o.len > 0) {
1636 o.data = calloc(1, o.len);
1637 if (o.data == NULL)
1638 error("no space to append '%s' to %s",
1639 config->defaults[i].data,
1640 dhcp_options[i].name);
1641 memcpy(o.data, lease->options[i].data,
1642 lease->options[i].len);
1643 memcpy(o.data + lease->options[i].len,
1644 config->defaults[i].data,
1645 config->defaults[i].len);
1646 script_set_env(prefix, buf,
1647 pretty_print_option(i, &o, 0));
1648 free(o.data);
1649 }
1650 break;
1651 }
1652 }
1653
1654 snprintf(buf, sizeof(buf), "%d", (int)lease->expiry);
1655 script_set_env(prefix, "expiry", buf);
1656 }
1657
1658 void
1659 script_write_params(char *prefix, struct client_lease *lease)
1660 {
1661 size_t fn_len = 0, sn_len = 0, pr_len = 0;
1662 struct imsg_hdr hdr;
1663 struct buf *buf;
1664 int i;
1665
1666 if (lease->filename != NULL)
1667 fn_len = strlen(lease->filename);
1668 if (lease->server_name != NULL)
1669 sn_len = strlen(lease->server_name);
1670 if (prefix != NULL)
1671 pr_len = strlen(prefix);
1672
1673 hdr.code = IMSG_SCRIPT_WRITE_PARAMS;
1674 hdr.len = sizeof(hdr) + sizeof(struct client_lease) +
1675 sizeof(size_t) + fn_len + sizeof(size_t) + sn_len +
1676 sizeof(size_t) + pr_len;
1677
1678 for (i = 0; i < 256; i++)
1679 hdr.len += sizeof(int) + lease->options[i].len;
1680
1681 scripttime = time(NULL);
1682
1683 buf = buf_open(hdr.len);
1684
1685 buf_add(buf, &hdr, sizeof(hdr));
1686 buf_add(buf, lease, sizeof(struct client_lease));
1687 buf_add(buf, &fn_len, sizeof(fn_len));
1688 buf_add(buf, lease->filename, fn_len);
1689 buf_add(buf, &sn_len, sizeof(sn_len));
1690 buf_add(buf, lease->server_name, sn_len);
1691 buf_add(buf, &pr_len, sizeof(pr_len));
1692 buf_add(buf, prefix, pr_len);
1693
1694 for (i = 0; i < 256; i++) {
1695 buf_add(buf, &lease->options[i].len,
1696 sizeof(lease->options[i].len));
1697 buf_add(buf, lease->options[i].data,
1698 lease->options[i].len);
1699 }
1700
1701 buf_close(privfd, buf);
1702 }
1703
1704 int
1705 script_go(void)
1706 {
1707 struct imsg_hdr hdr;
1708 struct buf *buf;
1709 int ret;
1710
1711 scripttime = time(NULL);
1712
1713 hdr.code = IMSG_SCRIPT_GO;
1714 hdr.len = sizeof(struct imsg_hdr);
1715
1716 buf = buf_open(hdr.len);
1717
1718 buf_add(buf, &hdr, sizeof(hdr));
1719 buf_close(privfd, buf);
1720
1721 bzero(&hdr, sizeof(hdr));
1722 buf_read(privfd, &hdr, sizeof(hdr));
1723 if (hdr.code != IMSG_SCRIPT_GO_RET)
1724 error("unexpected msg type %u", hdr.code);
1725 if (hdr.len != sizeof(hdr) + sizeof(int))
1726 error("received corrupted message");
1727 buf_read(privfd, &ret, sizeof(ret));
1728
1729 return (ret);
1730 }
1731
1732 int
1733 priv_script_go(void)
1734 {
1735 char *scriptName, *argv[2], **envp;
1736 int pid, wpid, wstatus;
1737
1738 scripttime = time(NULL);
1739
1740 scriptName = config->script_name;
1741 envp = client->scriptEnv;
1742
1743 argv[0] = scriptName;
1744 argv[1] = NULL;
1745
1746 pid = fork();
1747 if (pid < 0) {
1748 error("fork: %m");
1749 wstatus = 0;
1750 } else if (pid) {
1751 do {
1752 wpid = wait(&wstatus);
1753 } while (wpid != pid && wpid > 0);
1754 if (wpid < 0) {
1755 error("wait: %m");
1756 wstatus = 0;
1757 }
1758 } else {
1759 execve(scriptName, argv, envp);
1760 error("execve (%s, ...): %m", scriptName);
1761 }
1762
1763 script_flush_env();
1764
1765 return (WEXITSTATUS(wstatus));
1766 }
1767
1768 void
1769 script_set_env(const char *prefix, const char *name, const char *value)
1770 {
1771 int i, j, namelen;
1772
1773 /* No `` or $() command substitution allowed in environment values! */
1774 for (j = 0; j < strlen(value); j++)
1775 switch (value[j]) {
1776 case '`':
1777 case '$':
1778 warning("illegal character (%c) in value '%s'",
1779 value[j], value);
1780 /* Ignore this option */
1781 return;
1782 }
1783
1784 namelen = strlen(name);
1785
1786 for (i = 0; client->scriptEnv[i]; i++)
1787 if (strncmp(client->scriptEnv[i], name, namelen) == 0 &&
1788 client->scriptEnv[i][namelen] == '=')
1789 break;
1790
1791 if (client->scriptEnv[i])
1792 /* Reuse the slot. */
1793 free(client->scriptEnv[i]);
1794 else {
1795 /* New variable. Expand if necessary. */
1796 if (i >= client->scriptEnvsize - 1) {
1797 char **newscriptEnv;
1798 int newscriptEnvsize = client->scriptEnvsize + 50;
1799
1800 newscriptEnv = realloc(client->scriptEnv,
1801 newscriptEnvsize);
1802 if (newscriptEnv == NULL) {
1803 free(client->scriptEnv);
1804 client->scriptEnv = NULL;
1805 client->scriptEnvsize = 0;
1806 error("script_set_env: no memory for variable");
1807 }
1808 client->scriptEnv = newscriptEnv;
1809 client->scriptEnvsize = newscriptEnvsize;
1810 }
1811 /* need to set the NULL pointer at end of array beyond
1812 the new slot. */
1813 client->scriptEnv[i + 1] = NULL;
1814 }
1815 /* Allocate space and format the variable in the appropriate slot. */
1816 client->scriptEnv[i] = malloc(strlen(prefix) + strlen(name) + 1 +
1817 strlen(value) + 1);
1818 if (client->scriptEnv[i] == NULL)
1819 error("script_set_env: no memory for variable assignment");
1820 snprintf(client->scriptEnv[i], strlen(prefix) + strlen(name) +
1821 1 + strlen(value) + 1, "%s%s=%s", prefix, name, value);
1822 }
1823
1824 void
1825 script_flush_env(void)
1826 {
1827 int i;
1828
1829 for (i = 0; client->scriptEnv[i]; i++) {
1830 free(client->scriptEnv[i]);
1831 client->scriptEnv[i] = NULL;
1832 }
1833 client->scriptEnvsize = 0;
1834 }
1835
1836 int
1837 dhcp_option_ev_name(char *buf, size_t buflen, const struct option *option)
1838 {
1839 size_t i;
1840
1841 for (i = 0; option->name[i]; i++) {
1842 if (i + 1 == buflen)
1843 return 0;
1844 if (option->name[i] == '-')
1845 buf[i] = '_';
1846 else
1847 buf[i] = option->name[i];
1848 }
1849
1850 buf[i] = 0;
1851 return 1;
1852 }
1853
1854 void
1855 go_daemon(void)
1856 {
1857 char buf[256];
1858 int fd;
1859
1860 /*
1861 * Only once
1862 */
1863 if (no_daemon == 2)
1864 return;
1865
1866 /*
1867 * Setup pidfile, kill any dhclient already running for this
1868 * interface.
1869 */
1870 snprintf(buf, sizeof(buf), "/var/run/dhclient.%s.pid", orig_ifname);
1871 fd = open(buf, O_RDWR|O_CREAT, 0644);
1872 if (fd >= 0) {
1873 if (killclient(fd)) {
1874 fprintf(stderr,
1875 "starting dhclient on %s\n",
1876 orig_ifname);
1877 } else {
1878 fprintf(stderr,
1879 "restarting dhclient on %s\n",
1880 orig_ifname);
1881 }
1882 }
1883
1884 /*
1885 * Daemonize if requested
1886 */
1887 if (no_daemon == 0) {
1888 /* Stop logging to stderr... */
1889 log_perror = 0;
1890
1891 if (daemon(1, 0) == -1)
1892 error("daemon");
1893
1894 /* we are chrooted, daemon(3) fails to open /dev/null */
1895 if (nullfd != -1) {
1896 dup2(nullfd, STDIN_FILENO);
1897 dup2(nullfd, STDOUT_FILENO);
1898 dup2(nullfd, STDERR_FILENO);
1899 close(nullfd);
1900 nullfd = -1;
1901 }
1902 }
1903
1904 /*
1905 * No further daemonizations, write out pid file and lock.
1906 */
1907 no_daemon = 2;
1908 if (fd >= 0) {
1909 lseek(fd, 0L, SEEK_SET);
1910 ftruncate(fd, 0);
1911 snprintf(buf, sizeof(buf), "%ld\n", (long)getpid());
1912 write(fd, buf, strlen(buf));
1913 flock(fd, LOCK_EX);
1914 /* leave descriptor open and locked */
1915 }
1916 }
1917
1918 int
1919 check_option(struct client_lease *l, int option)
1920 {
1921 char *opbuf;
1922 char *sbuf;
1923
1924 /* we use this, since this is what gets passed to dhclient-script */
1925
1926 opbuf = pretty_print_option(option, &l->options[option], 0);
1927
1928 sbuf = option_as_string(option, l->options[option].data,
1929 l->options[option].len);
1930
1931 switch (option) {
1932 case DHO_SUBNET_MASK:
1933 case DHO_SWAP_SERVER:
1934 case DHO_BROADCAST_ADDRESS:
1935 case DHO_DHCP_SERVER_IDENTIFIER:
1936 case DHO_ROUTER_SOLICITATION_ADDRESS:
1937 case DHO_DHCP_REQUESTED_ADDRESS:
1938 if (ipv4addrs(opbuf) == 0) {
1939 warning("Invalid IP address in option %s: %s",
1940 dhcp_options[option].name, opbuf);
1941 return (0);
1942 }
1943 if (l->options[option].len != 4) { /* RFC 2132 */
1944 warning("warning: Only 1 IP address allowed in "
1945 "%s option; length %d, must be 4",
1946 dhcp_options[option].name,
1947 l->options[option].len);
1948 l->options[option].len = 4;
1949 }
1950 return (1);
1951 case DHO_TIME_SERVERS:
1952 case DHO_NAME_SERVERS:
1953 case DHO_ROUTERS:
1954 case DHO_DOMAIN_NAME_SERVERS:
1955 case DHO_LOG_SERVERS:
1956 case DHO_COOKIE_SERVERS:
1957 case DHO_LPR_SERVERS:
1958 case DHO_IMPRESS_SERVERS:
1959 case DHO_RESOURCE_LOCATION_SERVERS:
1960 case DHO_NIS_SERVERS:
1961 case DHO_NTP_SERVERS:
1962 case DHO_NETBIOS_NAME_SERVERS:
1963 case DHO_NETBIOS_DD_SERVER:
1964 case DHO_FONT_SERVERS:
1965 if (ipv4addrs(opbuf) == 0) {
1966 warning("Invalid IP address in option %s: %s",
1967 dhcp_options[option].name, opbuf);
1968 return (0);
1969 }
1970 return (1);
1971 case DHO_HOST_NAME:
1972 case DHO_DOMAIN_NAME:
1973 case DHO_NIS_DOMAIN:
1974 if (!res_hnok(sbuf)) {
1975 warning("Bogus Host Name option %d: %s (%s)", option,
1976 sbuf, opbuf);
1977 l->options[option].len = 0;
1978 free(l->options[option].data);
1979 }
1980 return (1);
1981 case DHO_PAD:
1982 case DHO_TIME_OFFSET:
1983 case DHO_BOOT_SIZE:
1984 case DHO_MERIT_DUMP:
1985 case DHO_ROOT_PATH:
1986 case DHO_EXTENSIONS_PATH:
1987 case DHO_IP_FORWARDING:
1988 case DHO_NON_LOCAL_SOURCE_ROUTING:
1989 case DHO_POLICY_FILTER:
1990 case DHO_MAX_DGRAM_REASSEMBLY:
1991 case DHO_DEFAULT_IP_TTL:
1992 case DHO_PATH_MTU_AGING_TIMEOUT:
1993 case DHO_PATH_MTU_PLATEAU_TABLE:
1994 case DHO_INTERFACE_MTU:
1995 case DHO_ALL_SUBNETS_LOCAL:
1996 case DHO_PERFORM_MASK_DISCOVERY:
1997 case DHO_MASK_SUPPLIER:
1998 case DHO_ROUTER_DISCOVERY:
1999 case DHO_STATIC_ROUTES:
2000 case DHO_TRAILER_ENCAPSULATION:
2001 case DHO_ARP_CACHE_TIMEOUT:
2002 case DHO_IEEE802_3_ENCAPSULATION:
2003 case DHO_DEFAULT_TCP_TTL:
2004 case DHO_TCP_KEEPALIVE_INTERVAL:
2005 case DHO_TCP_KEEPALIVE_GARBAGE:
2006 case DHO_VENDOR_ENCAPSULATED_OPTIONS:
2007 case DHO_NETBIOS_NODE_TYPE:
2008 case DHO_NETBIOS_SCOPE:
2009 case DHO_X_DISPLAY_MANAGER:
2010 case DHO_DHCP_LEASE_TIME:
2011 case DHO_DHCP_OPTION_OVERLOAD:
2012 case DHO_DHCP_MESSAGE_TYPE:
2013 case DHO_DHCP_PARAMETER_REQUEST_LIST:
2014 case DHO_DHCP_MESSAGE:
2015 case DHO_DHCP_MAX_MESSAGE_SIZE:
2016 case DHO_DHCP_RENEWAL_TIME:
2017 case DHO_DHCP_REBINDING_TIME:
2018 case DHO_DHCP_CLASS_IDENTIFIER:
2019 case DHO_DHCP_CLIENT_IDENTIFIER:
2020 case DHO_DHCP_USER_CLASS_ID:
2021 case DHO_TFTP_SERVER:
2022 case DHO_END:
2023 return (1);
2024 default:
2025 if (!unknown_ok)
2026 warning("unknown dhcp option value 0x%x", option);
2027 return (unknown_ok);
2028 }
2029 }
2030
2031 int
2032 res_hnok(const char *name)
2033 {
2034 const char *dn = name;
2035 int pch = '.', ch = *dn++;
2036 int warn = 0;
2037
2038 while (ch != '\0') {
2039 int nch = *dn++;
2040
2041 if (ch == '.') {
2042 ;
2043 } else if (pch == '.' || nch == '.' || nch == '\0') {
2044 if (!isalnum(ch))
2045 return (0);
2046 } else if (!isalnum(ch) && ch != '-' && ch != '_')
2047 return (0);
2048 else if (ch == '_' && warn == 0) {
2049 warning("warning: hostname %s contains an "
2050 "underscore which violates RFC 952", name);
2051 warn++;
2052 }
2053 pch = ch, ch = nch;
2054 }
2055 return (1);
2056 }
2057
2058 /* Does buf consist only of dotted decimal ipv4 addrs?
2059 * return how many if so,
2060 * otherwise, return 0
2061 */
2062 int
2063 ipv4addrs(char * buf)
2064 {
2065 struct in_addr jnk;
2066 int count = 0;
2067
2068 while (inet_aton(buf, &jnk) == 1){
2069 count++;
2070 while (*buf == '.' || isdigit(*buf))
2071 buf++;
2072 if (*buf == '\0')
2073 return (count);
2074 while (*buf == ' ')
2075 buf++;
2076 }
2077 return (0);
2078 }
2079
2080 char *
2081 option_as_string(unsigned int code, unsigned char *data, int len)
2082 {
2083 static char optbuf[32768]; /* XXX */
2084 char *op = optbuf;
2085 int opleft = sizeof(optbuf);
2086 unsigned char *dp = data;
2087
2088 if (code > 255)
2089 error("option_as_string: bad code %d", code);
2090
2091 for (; dp < data + len; dp++) {
2092 if (!isascii(*dp) || !isprint(*dp)) {
2093 if (dp + 1 != data + len || *dp != 0) {
2094 size_t oplen;
2095 snprintf(op, opleft, "\\%03o", *dp);
2096 oplen = strlen(op);
2097 op += oplen;
2098 opleft -= oplen;
2099 }
2100 } else if (*dp == '"' || *dp == '\'' || *dp == '$' ||
2101 *dp == '`' || *dp == '\\') {
2102 *op++ = '\\';
2103 *op++ = *dp;
2104 opleft -= 2;
2105 } else {
2106 *op++ = *dp;
2107 opleft--;
2108 }
2109 }
2110 if (opleft < 1)
2111 goto toobig;
2112 *op = 0;
2113 return optbuf;
2114 toobig:
2115 warning("dhcp option too large");
2116 return "<error>";
2117 }
2118
2119 int
2120 fork_privchld(int fd, int fd2)
2121 {
2122 struct pollfd pfd[1];
2123 int nfds, pfail = 0;
2124 pid_t pid;
2125 int omask;
2126
2127 omask = sigblock(sigmask(SIGINT)|sigmask(SIGHUP));
2128 pid = fork();
2129 if (pid > 0)
2130 monitor_pid = pid;
2131 sigsetmask(omask);
2132
2133 switch (pid) {
2134 case -1:
2135 error("cannot fork");
2136 break;
2137 case 0:
2138 break;
2139 default:
2140 return (0);
2141 }
2142
2143 if (chdir("/") == -1)
2144 error("chdir(\"/\")");
2145
2146 setproctitle("%s [priv]", ifi->name);
2147
2148 dup2(nullfd, STDIN_FILENO);
2149 dup2(nullfd, STDOUT_FILENO);
2150 dup2(nullfd, STDERR_FILENO);
2151 close(nullfd);
2152 close(fd2);
2153
2154 for (;;) {
2155 pfd[0].fd = fd;
2156 pfd[0].events = POLLIN;
2157 if ((nfds = poll(pfd, 1, INFTIM)) == -1)
2158 if (errno != EINTR)
2159 error("poll error");
2160
2161 /*
2162 * Handle temporary errors, but bail if they persist.
2163 */
2164 if (nfds == 0 || !(pfd[0].revents & POLLIN)) {
2165 if (pfail > POLL_FAILURES)
2166 error("poll failed > %d times", POLL_FAILURES);
2167 sleep(pfail * POLL_FAILURE_WAIT);
2168 pfail++;
2169 continue;
2170 }
2171
2172 dispatch_imsg(fd);
2173 }
2174 }
2175
2176 void
2177 get_ifname(char *ifname, char *arg)
2178 {
2179 struct ifgroupreq ifgr;
2180 struct ifg_req *ifg;
2181 int s, len;
2182
2183 if (!strcmp(arg, "egress")) {
2184 s = socket(AF_INET, SOCK_DGRAM, 0);
2185 if (s == -1)
2186 error("socket error");
2187 bzero(&ifgr, sizeof(ifgr));
2188 strlcpy(ifgr.ifgr_name, "egress", sizeof(ifgr.ifgr_name));
2189 if (ioctl(s, SIOCGIFGMEMB, (caddr_t)&ifgr) == -1) {
2190 if (errno == ENOENT)
2191 error("no interface in group egress found");
2192 error("ioctl SIOCGIFGMEMB: %m");
2193 }
2194 len = ifgr.ifgr_len;
2195 if ((ifgr.ifgr_groups = calloc(1, len)) == NULL)
2196 error("get_ifname");
2197 if (ioctl(s, SIOCGIFGMEMB, (caddr_t)&ifgr) == -1)
2198 error("ioctl SIOCGIFGMEMB: %m");
2199
2200 arg = NULL;
2201 for (ifg = ifgr.ifgr_groups;
2202 ifg && len >= sizeof(struct ifg_req); ifg++) {
2203 len -= sizeof(struct ifg_req);
2204 if (arg)
2205 error("too many interfaces in group egress");
2206 arg = ifg->ifgrq_member;
2207 }
2208
2209 if (strlcpy(ifi->name, arg, IFNAMSIZ) >= IFNAMSIZ)
2210 error("Interface name too long: %m");
2211
2212 free(ifgr.ifgr_groups);
2213 close(s);
2214 } else if (strlcpy(ifi->name, arg, IFNAMSIZ) >= IFNAMSIZ)
2215 error("Interface name too long");
2216 }
2217
2218 static
2219 void
2220 sig_handle(int signo)
2221 {
2222 if (monitor_pid > 0)
2223 kill(monitor_pid, signo);
2224 fprintf(stderr, "killed by signal\n");
2225 exit(1);
2226 }
2227
2228 static
2229 int
2230 killclient(int fd)
2231 {
2232 int noclient = 1;
2233
2234 /*
2235 * Kill previously running dhclient
2236 */
2237 if (flock(fd, LOCK_EX|LOCK_NB) < 0) {
2238 char buf[256];
2239 ssize_t n;
2240 pid_t pid;
2241
2242 lseek(fd, 0L, SEEK_SET);
2243 n = read(fd, buf, sizeof(buf));
2244 if (n > 0) {
2245 buf[n-1] = 0;
2246 pid = strtol(buf, NULL, 10);
2247 if ((int)pid > 0) {
2248 noclient = 0;
2249 kill(pid, SIGINT);
2250 }
2251 }
2252 if (flock(fd, LOCK_EX|LOCK_NB) < 0)
2253 usleep(20000);
2254 while (flock(fd, LOCK_EX|LOCK_NB) < 0)
2255 sleep(1);
2256 }
2257 return noclient;
2258 }
DragonFly BSD