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kgdb(1): Add missing "
[dragonfly.git] / sbin / dhclient / dhclient.c
blob87f7580f9267f460a46f1a0b095e09b884e9b739
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) __dead2;
94 int check_option(struct client_lease *l, int option);
95 int check_classless_option(unsigned char *data, int len);
96 int ipv4addrs(char * buf);
97 int res_hnok(const char *dn);
98 char *option_as_string(unsigned int code, unsigned char *data, int len);
99 int fork_privchld(int, int);
100 void get_ifname(char *, char *);
101 static void sig_handle(int sig);
102 static int killclient(int fd);
103
104 time_t scripttime;
105 static FILE *leaseFile;
106
107 int
108 findproto(char *cp, int n)
109 {
110 struct sockaddr *sa;
111 unsigned int i;
112
113 if (n == 0)
114 return -1;
115 for (i = 1; i; i <<= 1) {
116 if (i & n) {
117 sa = (struct sockaddr *)cp;
118 switch (i) {
119 case RTA_IFA:
120 case RTA_DST:
121 case RTA_GATEWAY:
122 case RTA_NETMASK:
123 if (sa->sa_family == AF_INET)
124 return AF_INET;
125 if (sa->sa_family == AF_INET6)
126 return AF_INET6;
127 break;
128 case RTA_IFP:
129 break;
130 }
131 RT_ADVANCE(cp, sa);
132 }
133 }
134 return (-1);
135 }
136
137 struct sockaddr *
138 get_ifa(char *cp, int n)
139 {
140 struct sockaddr *sa;
141 int i;
142
143 if (n == 0)
144 return (NULL);
145 for (i = 1; i; i <<= 1)
146 if (i & n) {
147 sa = (struct sockaddr *)cp;
148 if (i == RTA_IFA)
149 return (sa);
150 RT_ADVANCE(cp, sa);
151 }
152
153 return (NULL);
154 }
155 struct iaddr defaddr = { .len = 4 }; /* NULL is for silence warnings */
156
157 void
158 routehandler(void)
159 {
160 int linkstat;
161 char msg[2048];
162 struct rt_msghdr *rtm;
163 struct if_msghdr *ifm;
164 struct ifa_msghdr *ifam;
165 struct if_announcemsghdr *ifan;
166 struct client_lease *l;
167 struct sockaddr *sa;
168 struct iaddr a;
169 ssize_t n;
170 char *errmsg, buf[64];
171
172 do {
173 n = read(routefd, &msg, sizeof(msg));
174 } while (n == -1 && errno == EINTR);
175
176 rtm = (struct rt_msghdr *)msg;
177 if (n < sizeof(rtm->rtm_msglen) || n < rtm->rtm_msglen ||
178 rtm->rtm_version != RTM_VERSION)
179 return;
180
181 switch (rtm->rtm_type) {
182 case RTM_NEWADDR:
183 ifam = (struct ifa_msghdr *)rtm;
184 if (ifam->ifam_index != ifi->index)
185 break;
186 if (findproto((char *)(ifam + 1), ifam->ifam_addrs) != AF_INET)
187 break;
188 sa = get_ifa((char *)(ifam + 1), ifam->ifam_addrs);
189 if (sa == NULL) {
190 errmsg = "sa == NULL";
191 goto die;
192 }
193
194 if ((a.len = sizeof(struct in_addr)) > sizeof(a.iabuf))
195 error("king bula sez: len mismatch");
196 memcpy(a.iabuf, &((struct sockaddr_in *)sa)->sin_addr, a.len);
197 if (addr_eq(a, defaddr))
198 break;
199
200 /* state_panic() can try unexpired existing leases */
201 if (client->active && addr_eq(a, client->active->address))
202 break;
203 for (l = client->leases; l != NULL; l = l->next)
204 if (addr_eq(a, l->address))
205 break;
206
207 if (l != NULL)
208 /* new addr is the one we set */
209 break;
210 snprintf(buf, sizeof(buf), "%s: %s",
211 "new address not one we set", piaddr(a));
212 errmsg = buf;
213 goto die;
214 case RTM_DELADDR:
215 ifam = (struct ifa_msghdr *)rtm;
216 if (ifam->ifam_index != ifi->index)
217 break;
218 if (findproto((char *)(ifam + 1), ifam->ifam_addrs) != AF_INET)
219 break;
220 /* XXX check addrs like RTM_NEWADDR instead of this? */
221 if (scripttime == 0 || time(NULL) < scripttime + 10)
222 break;
223 errmsg = "interface address deleted";
224 goto die;
225 case RTM_IFINFO:
226 ifm = (struct if_msghdr *)rtm;
227 if (ifm->ifm_index != ifi->index)
228 break;
229 if ((rtm->rtm_flags & RTF_UP) == 0) {
230 errmsg = "interface down";
231 goto die;
232 }
233
234 linkstat =
235 LINK_STATE_IS_UP(ifm->ifm_data.ifi_link_state) ? 1 : 0;
236 if (linkstat != ifi->linkstat) {
237 #ifdef DEBUG
238 debug("link state %s -> %s",
239 ifi->linkstat ? "up" : "down",
240 linkstat ? "up" : "down");
241 #endif
242 ifi->linkstat = interface_status(ifi->name);
243 if (ifi->linkstat) {
244 client->state = S_REBOOTING;
245 state_reboot();
246 }
247 }
248 break;
249 case RTM_IFANNOUNCE:
250 ifan = (struct if_announcemsghdr *)rtm;
251 if (ifan->ifan_what == IFAN_DEPARTURE &&
252 ifan->ifan_index == ifi->index) {
253 errmsg = "interface departure";
254 goto die;
255 }
256 break;
257 default:
258 break;
259 }
260 return;
261
262 die:
263 script_init("FAIL");
264 script_go();
265 error("routehandler: %s", errmsg);
266 }
267
268 int
269 main(int argc, char *argv[])
270 {
271 int ch, fd;
272 int pipe_fd[2];
273 int quiet = 0;
274 int dokillclient = 0;
275 int i;
276 struct passwd *pw;
277
278 /* Initially, log errors to stderr as well as to syslogd. */
279 openlog(getprogname(), LOG_PID | LOG_NDELAY, DHCPD_LOG_FACILITY);
280 setlogmask(LOG_UPTO(LOG_INFO));
281
282 signal(SIGINT, sig_handle);
283 signal(SIGHUP, sig_handle);
284
285 while ((ch = getopt(argc, argv, "c:dl:quwx")) != -1) {
286 switch (ch) {
287 case 'c':
288 path_dhclient_conf = optarg;
289 break;
290 case 'd':
291 no_daemon = 1;
292 break;
293 case 'l':
294 path_dhclient_db = optarg;
295 break;
296 case 'q':
297 quiet = 1;
298 break;
299 case 'u':
300 unknown_ok = 0;
301 break;
302 case 'w':
303 stayalive = 1;
304 break;
305 case 'x':
306 dokillclient = 1;
307 break;
308 default:
309 usage();
310 }
311 }
312
313 argc -= optind;
314 argv += optind;
315
316 if (argc != 1)
317 usage();
318 orig_ifname = argv[0];
319
320 if (dokillclient) {
321 char buf[256];
322
323 snprintf(buf, sizeof(buf),
324 "/var/run/dhclient.%s.pid", orig_ifname);
325 fd = open(buf, O_RDWR, 0644);
326 if (fd < 0 || killclient(fd)) {
327 fprintf(stderr,
328 "no dhclient running on %s\n",
329 orig_ifname);
330 } else {
331 fprintf(stderr,
332 "stopping dhclient on %s\n",
333 orig_ifname);
334 }
335 if (fd >= 0)
336 close(fd);
337 exit(1);
338 }
339
340 if ((nullfd = open(_PATH_DEVNULL, O_RDWR, 0)) == -1)
341 error("cannot open %s: %m", _PATH_DEVNULL);
342
343 /*
344 * If asked to stay alive forever get our daemon going right now
345 * Then set up to fork/monitor and refork on exit.
346 *
347 * When I say 'forever' I really mean it. If there are configuration
348 * problems or missing interfaces or whatever, dhclient will wait
349 * 10 seconds and try again.
350 */
351 if (stayalive) {
352 pid_t pid;
353 pid_t rpid;
354 int omask;
355
356 go_daemon();
357
358 for (;;) {
359 omask = sigblock(sigmask(SIGINT) | sigmask(SIGHUP));
360 pid = fork();
361 if (pid > 0)
362 monitor_pid = pid;
363 sigsetmask(omask);
364
365 if (pid == 0) /* child falls out of loop */
366 break;
367 while (pid > 0) {
368 rpid = waitpid(pid, NULL, 0);
369 if (rpid == pid)
370 break;
371 if (rpid != EINTR)
372 break;
373 }
374 sleep(10);
375 }
376 }
377
378 ifi = calloc(1, sizeof(*ifi));
379 if (ifi == NULL)
380 error("ifi calloc");
381 client = calloc(1, sizeof(*client));
382 if (client == NULL)
383 error("client calloc");
384 config = calloc(1, sizeof(*config));
385 if (config == NULL)
386 error("config calloc");
387
388 get_ifname(ifi->name, argv[0]);
389
390 if (path_dhclient_db == NULL && asprintf(&path_dhclient_db, "%s.%s",
391 _PATH_DHCLIENT_DB, ifi->name) == -1)
392 error("asprintf");
393
394 if (quiet)
395 log_perror = 0;
396
397 tzset();
398
399 memset(&sockaddr_broadcast, 0, sizeof(sockaddr_broadcast));
400 sockaddr_broadcast.sin_family = AF_INET;
401 sockaddr_broadcast.sin_port = htons(REMOTE_PORT);
402 sockaddr_broadcast.sin_addr.s_addr = INADDR_BROADCAST;
403 sockaddr_broadcast.sin_len = sizeof(sockaddr_broadcast);
404 inaddr_any.s_addr = INADDR_ANY;
405
406 read_client_conf();
407
408 if (interface_status(ifi->name) == 0) {
409 interface_link_forceup(ifi->name);
410 /* Give it up to 4 seconds of silent grace to find link */
411 i = -4;
412 } else {
413 i = 0;
414 }
415
416 while (!(ifi->linkstat = interface_status(ifi->name))) {
417 if (i == 0)
418 fprintf(stderr, "%s: no link ...", ifi->name);
419 else if (i > 0)
420 fprintf(stderr, ".");
421 fflush(stderr);
422 if (++i > config->link_timeout) {
423 fprintf(stderr, " sleeping\n");
424 goto dispatch;
425 }
426 sleep(1);
427 }
428 if (i > 0)
429 fprintf(stderr, " got link\n");
430
431 dispatch:
432 if ((pw = getpwnam("_dhcp")) == NULL)
433 error("no such user: _dhcp");
434
435 if (pipe(pipe_fd) == -1)
436 error("pipe");
437
438 go_daemon();
439 fork_privchld(pipe_fd[0], pipe_fd[1]);
440
441 close(pipe_fd[0]);
442 privfd = pipe_fd[1];
443
444 if ((fd = open(path_dhclient_db, O_RDONLY|O_EXLOCK|O_CREAT, 0)) == -1)
445 error("can't open and lock %s: %m", path_dhclient_db);
446 read_client_leases();
447 if ((leaseFile = fopen(path_dhclient_db, "w")) == NULL)
448 error("can't open %s: %m", path_dhclient_db);
449 rewrite_client_leases();
450 close(fd);
451
452 if ((routefd = socket(PF_ROUTE, SOCK_RAW, 0)) == -1)
453 error("socket(PF_ROUTE, SOCK_RAW): %m");
454
455 /* set up the interface */
456 discover_interface();
457
458 if (chroot(_PATH_VAREMPTY) == -1)
459 error("chroot");
460 if (chdir("/") == -1)
461 error("chdir(\"/\")");
462
463 if (setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) == -1)
464 error("setresgid");
465 if (setgroups(1, &pw->pw_gid) == -1)
466 error("setgroups");
467 if (setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid) == -1)
468 error("setresuid");
469
470 endpwent();
471
472 setproctitle("%s", ifi->name);
473
474 if (ifi->linkstat) {
475 client->state = S_REBOOTING;
476 state_reboot();
477 }
478 dispatch();
479
480 /* not reached */
481 return (0);
482 }
483
484 void
485 usage(void)
486 {
487 fprintf(stderr, "usage: %s [-dqu] [-c file] [-l file] interface\n",
488 getprogname());
489 exit(1);
490 }
491
492 /*
493 * Individual States:
494 *
495 * Each routine is called from the dhclient_state_machine() in one of
496 * these conditions:
497 * -> entering INIT state
498 * -> recvpacket_flag == 0: timeout in this state
499 * -> otherwise: received a packet in this state
500 *
501 * Return conditions as handled by dhclient_state_machine():
502 * Returns 1, sendpacket_flag = 1: send packet, reset timer.
503 * Returns 1, sendpacket_flag = 0: just reset the timer (wait for a milestone).
504 * Returns 0: finish the nap which was interrupted for no good reason.
505 *
506 * Several per-interface variables are used to keep track of the process:
507 * active_lease: the lease that is being used on the interface
508 * (null pointer if not configured yet).
509 * offered_leases: leases corresponding to DHCPOFFER messages that have
510 * been sent to us by DHCP servers.
511 * acked_leases: leases corresponding to DHCPACK messages that have been
512 * sent to us by DHCP servers.
513 * sendpacket: DHCP packet we're trying to send.
514 * destination: IP address to send sendpacket to
515 * In addition, there are several relevant per-lease variables.
516 * T1_expiry, T2_expiry, lease_expiry: lease milestones
517 * In the active lease, these control the process of renewing the lease;
518 * In leases on the acked_leases list, this simply determines when we
519 * can no longer legitimately use the lease.
520 */
521 void
522 state_reboot(void)
523 {
524 /* Cancel all timeouts, since a link state change gets us here
525 and can happen anytime. */
526 cancel_timeout();
527
528 /* If we don't remember an active lease, go straight to INIT. */
529 if (!client->active || client->active->is_bootp) {
530 client->state = S_INIT;
531 state_init();
532 return;
533 }
534
535 /* make_request doesn't initialize xid because it normally comes
536 from the DHCPDISCOVER, but we haven't sent a DHCPDISCOVER,
537 so pick an xid now. */
538 client->xid = arc4random();
539
540 /* Make a DHCPREQUEST packet, and set appropriate per-interface
541 flags. */
542 make_request(client->active);
543 client->destination = iaddr_broadcast;
544 client->first_sending = time(NULL);
545 client->interval = 0;
546
547 send_request();
548 }
549
550 /*
551 * Called when a lease has completely expired and we've
552 * been unable to renew it.
553 */
554 void
555 state_init(void)
556 {
557 /* Make a DHCPDISCOVER packet, and set appropriate per-interface
558 flags. */
559 make_discover(client->active);
560 client->xid = client->packet.xid;
561 client->destination = iaddr_broadcast;
562 client->state = S_SELECTING;
563 client->first_sending = time(NULL);
564 client->interval = 0;
565
566 send_discover();
567 }
568
569 /*
570 * state_selecting is called when one or more DHCPOFFER packets
571 * have been received and a configurable period of time has passed.
572 */
573 void
574 state_selecting(void)
575 {
576 struct client_lease *lp, *next, *picked;
577 time_t cur_time;
578
579 /* Cancel state_selecting and send_discover timeouts, since either
580 one could have got us here. */
581 cancel_timeout();
582
583 /* We have received one or more DHCPOFFER packets. Currently,
584 the only criterion by which we judge leases is whether or
585 not we get a response when we arp for them. */
586 picked = NULL;
587 for (lp = client->offered_leases; lp; lp = next) {
588 next = lp->next;
589
590 if (!picked) {
591 picked = lp;
592 } else {
593 make_decline(lp);
594 send_decline();
595 free_client_lease(lp);
596 }
597 }
598 client->offered_leases = NULL;
599
600 /* If we just tossed all the leases we were offered, go back
601 to square one. */
602 if (!picked) {
603 client->state = S_INIT;
604 state_init();
605 return;
606 }
607 picked->next = NULL;
608
609 time(&cur_time);
610
611 /* If it was a BOOTREPLY, we can just take the address right now. */
612 if (!picked->options[DHO_DHCP_MESSAGE_TYPE].len) {
613 client->new = picked;
614
615 /* Make up some lease expiry times
616 XXX these should be configurable. */
617 client->new->expiry = cur_time + 12000;
618 client->new->renewal += cur_time + 8000;
619 client->new->rebind += cur_time + 10000;
620
621 client->state = S_REQUESTING;
622
623 /* Bind to the address we received. */
624 bind_lease();
625 return;
626 }
627
628 /* Go to the REQUESTING state. */
629 client->destination = iaddr_broadcast;
630 client->state = S_REQUESTING;
631 client->first_sending = cur_time;
632 client->interval = 0;
633
634 /* Make a DHCPREQUEST packet from the lease we picked. */
635 make_request(picked);
636 client->xid = client->packet.xid;
637
638 /* Toss the lease we picked - we'll get it back in a DHCPACK. */
639 free_client_lease(picked);
640
641 send_request();
642 }
643
644 void
645 dhcpack(struct iaddr client_addr, struct option_data *options)
646 {
647 struct client_lease *lease;
648 time_t cur_time;
649
650
651 if (client->state != S_REBOOTING &&
652 client->state != S_REQUESTING &&
653 client->state != S_RENEWING &&
654 client->state != S_REBINDING)
655 return;
656
657
658 lease = packet_to_lease(options);
659 if (!lease) {
660 note("packet_to_lease failed.");
661 return;
662 }
663
664 client->new = lease;
665
666 /* Stop resending DHCPREQUEST. */
667 cancel_timeout();
668
669 /* Figure out the lease time. */
670 if (client->new->options[DHO_DHCP_LEASE_TIME].data)
671 client->new->expiry =
672 getULong(client->new->options[DHO_DHCP_LEASE_TIME].data);
673 else
674 client->new->expiry = DEFAULT_LEASE_TIME;
675 /* A number that looks negative here is really just very large,
676 because the lease expiry offset is unsigned. */
677 if (client->new->expiry < 0)
678 client->new->expiry = TIME_MAX;
679 /* XXX should be fixed by resetting the client state */
680 if (client->new->expiry < 60)
681 client->new->expiry = 60;
682
683 /* Take the server-provided renewal time if there is one;
684 otherwise figure it out according to the spec. */
685 if (client->new->options[DHO_DHCP_RENEWAL_TIME].len)
686 client->new->renewal =
687 getULong(client->new->options[DHO_DHCP_RENEWAL_TIME].data);
688 else
689 client->new->renewal = client->new->expiry / 2;
690
691 /* Same deal with the rebind time. */
692 if (client->new->options[DHO_DHCP_REBINDING_TIME].len)
693 client->new->rebind =
694 getULong(client->new->options[DHO_DHCP_REBINDING_TIME].data);
695 else
696 client->new->rebind = client->new->renewal +
697 client->new->renewal / 2 + client->new->renewal / 4;
698
699 time(&cur_time);
700
701 client->new->expiry += cur_time;
702 /* Lease lengths can never be negative. */
703 if (client->new->expiry < cur_time)
704 client->new->expiry = TIME_MAX;
705 client->new->renewal += cur_time;
706 if (client->new->renewal < cur_time)
707 client->new->renewal = TIME_MAX;
708 client->new->rebind += cur_time;
709 if (client->new->rebind < cur_time)
710 client->new->rebind = TIME_MAX;
711
712 bind_lease();
713 }
714
715 void
716 bind_lease(void)
717 {
718 /* Run the client script with the new parameters. */
719 script_init((client->state == S_REQUESTING ? "BOUND" :
720 (client->state == S_RENEWING ? "RENEW" :
721 (client->state == S_REBOOTING ? "REBOOT" : "REBIND"))));
722 if (client->active && client->state != S_REBOOTING)
723 script_write_params("old_", client->active);
724 script_write_params("new_", client->new);
725 script_go();
726
727 /* Replace the old active lease with the new one. */
728 if (client->active)
729 free_client_lease(client->active);
730 client->active = client->new;
731 client->new = NULL;
732
733 /* Write out new leases file. */
734 rewrite_client_leases();
735
736 /* Set timeout to start the renewal process. */
737 set_timeout(client->active->renewal, state_bound);
738
739 note("bound to %s -- renewal in %lld seconds.",
740 piaddr(client->active->address),
741 (long long)(client->active->renewal - time(NULL)));
742 client->state = S_BOUND;
743 }
744
745 /*
746 * state_bound is called when we've successfully bound to a particular
747 * lease, but the renewal time on that lease has expired. We are
748 * expected to unicast a DHCPREQUEST to the server that gave us our
749 * original lease.
750 */
751 void
752 state_bound(void)
753 {
754 /* T1 has expired. */
755 make_request(client->active);
756 client->xid = client->packet.xid;
757
758 if (client->active->options[DHO_DHCP_SERVER_IDENTIFIER].len == 4) {
759 memcpy(client->destination.iabuf,
760 client->active->options[DHO_DHCP_SERVER_IDENTIFIER].data,
761 4);
762 client->destination.len = 4;
763 } else
764 client->destination = iaddr_broadcast;
765
766 client->first_sending = time(NULL);
767 client->interval = 0;
768 client->state = S_RENEWING;
769
770 send_request();
771 }
772
773 void
774 dhcpoffer(struct iaddr client_addr, struct option_data *options)
775 {
776 struct client_lease *lease, *lp;
777 int i;
778 time_t stop_selecting;
779 char *name = options[DHO_DHCP_MESSAGE_TYPE].len ? "DHCPOFFER" :
780 "BOOTREPLY";
781
782
783 if (client->state != S_SELECTING)
784 return;
785
786
787 /* If this lease doesn't supply the minimum required parameters,
788 blow it off. */
789 for (i = 0; config->required_options[i]; i++) {
790 if (!options[config->required_options[i]].len) {
791 note("%s isn't satisfactory.", name);
792 return;
793 }
794 }
795
796 /* If we've already seen this lease, don't record it again. */
797 for (lease = client->offered_leases;
798 lease; lease = lease->next) {
799 if (lease->address.len == sizeof(client->packet.yiaddr) &&
800 !memcmp(lease->address.iabuf,
801 &client->packet.yiaddr, lease->address.len)) {
802 #ifdef DEBUG
803 debug("%s already seen.", name);
804 #endif
805 return;
806 }
807 }
808
809 lease = packet_to_lease(options);
810 if (!lease) {
811 note("packet_to_lease failed.");
812 return;
813 }
814
815 /*
816 * Reject offers whose subnet is already configured on another
817 * interface.
818 */
819 if (subnet_exists(lease))
820 return;
821
822 /* If this lease was acquired through a BOOTREPLY, record that
823 fact. */
824 if (!options[DHO_DHCP_MESSAGE_TYPE].len)
825 lease->is_bootp = 1;
826
827 /* Figure out when we're supposed to stop selecting. */
828 stop_selecting = client->first_sending + config->select_interval;
829
830 /* If this is the lease we asked for, put it at the head of the
831 list, and don't mess with the arp request timeout. */
832 if (addr_eq(lease->address, client->requested_address)) {
833 lease->next = client->offered_leases;
834 client->offered_leases = lease;
835 } else {
836 /* Put the lease at the end of the list. */
837 lease->next = NULL;
838 if (!client->offered_leases)
839 client->offered_leases = lease;
840 else {
841 for (lp = client->offered_leases; lp->next;
842 lp = lp->next)
843 ; /* nothing */
844 lp->next = lease;
845 }
846 }
847
848 /* If the selecting interval has expired, go immediately to
849 state_selecting(). Otherwise, time out into
850 state_selecting at the select interval. */
851 if (stop_selecting <= time(NULL))
852 state_selecting();
853 else {
854 set_timeout(stop_selecting, state_selecting);
855 }
856 }
857
858 /*
859 * Allocate a client_lease structure and initialize it from the
860 * parameters in the specified packet.
861 */
862 struct client_lease *
863 packet_to_lease(struct option_data *options)
864 {
865 struct client_lease *lease;
866 int i;
867
868 lease = malloc(sizeof(struct client_lease));
869
870 if (!lease) {
871 warning("dhcpoffer: no memory to record lease.");
872 return (NULL);
873 }
874
875 memset(lease, 0, sizeof(*lease));
876
877 /* Copy the lease options. */
878 for (i = 0; i < 256; i++) {
879 if (options[i].len) {
880 lease->options[i] = options[i];
881 options[i].data = NULL;
882 options[i].len = 0;
883 if (!check_option(lease, i)) {
884 warning("Invalid lease option - ignoring offer");
885 free_client_lease(lease);
886 return (NULL);
887 }
888 }
889 }
890
891 lease->address.len = sizeof(client->packet.yiaddr);
892 memcpy(lease->address.iabuf, &client->packet.yiaddr,
893 lease->address.len);
894
895 /* If the server name was filled out, copy it. */
896 if ((!lease->options[DHO_DHCP_OPTION_OVERLOAD].len ||
897 !(lease->options[DHO_DHCP_OPTION_OVERLOAD].data[0] & 2)) &&
898 client->packet.sname[0]) {
899 lease->server_name = malloc(DHCP_SNAME_LEN + 1);
900 if (!lease->server_name) {
901 warning("dhcpoffer: no memory for server name.");
902 free_client_lease(lease);
903 return (NULL);
904 }
905 memcpy(lease->server_name, client->packet.sname,
906 DHCP_SNAME_LEN);
907 lease->server_name[DHCP_SNAME_LEN] = '\0';
908 if (!res_hnok(lease->server_name)) {
909 warning("Bogus server name %s", lease->server_name);
910 free(lease->server_name);
911 lease->server_name = NULL;
912 }
913 }
914
915 /* Ditto for the filename. */
916 if ((!lease->options[DHO_DHCP_OPTION_OVERLOAD].len ||
917 !(lease->options[DHO_DHCP_OPTION_OVERLOAD].data[0] & 1)) &&
918 client->packet.file[0]) {
919 /* Don't count on the NUL terminator. */
920 lease->filename = malloc(DHCP_FILE_LEN + 1);
921 if (!lease->filename) {
922 warning("dhcpoffer: no memory for filename.");
923 free_client_lease(lease);
924 return (NULL);
925 }
926 memcpy(lease->filename, client->packet.file, DHCP_FILE_LEN);
927 lease->filename[DHCP_FILE_LEN] = '\0';
928 }
929 return lease;
930 }
931
932 void
933 dhcpnak(struct iaddr client_addr, struct option_data *options)
934 {
935
936 if (client->state != S_REBOOTING &&
937 client->state != S_REQUESTING &&
938 client->state != S_RENEWING &&
939 client->state != S_REBINDING)
940 return;
941
942
943 if (!client->active) {
944 note("DHCPNAK with no active lease.");
945 return;
946 }
947
948 free_client_lease(client->active);
949 client->active = NULL;
950
951 /* Stop sending DHCPREQUEST packets... */
952 cancel_timeout();
953
954 client->state = S_INIT;
955 state_init();
956 }
957
958 /*
959 * Send out a DHCPDISCOVER packet, and set a timeout to send out another
960 * one after the right interval has expired. If we don't get an offer by
961 * the time we reach the panic interval, call the panic function.
962 */
963 void
964 send_discover(void)
965 {
966 time_t cur_time;
967 int interval, increase = 1;
968
969 time(&cur_time);
970
971 /* Figure out how long it's been since we started transmitting. */
972 interval = cur_time - client->first_sending;
973
974 /* If we're past the panic timeout, call the script and tell it
975 we haven't found anything for this interface yet. */
976 if (interval > config->timeout) {
977 state_panic();
978 return;
979 }
980
981 /*
982 * If we're supposed to increase the interval, do so. If it's
983 * currently zero (i.e., we haven't sent any packets yet), set
984 * it to initial_interval; otherwise, add to it a random
985 * number between zero and two times itself. On average, this
986 * means that it will double with every transmission.
987 */
988 if (increase) {
989 if (!client->interval)
990 client->interval = config->initial_interval;
991 else {
992 client->interval += (arc4random() >> 2) %
993 (2 * client->interval);
994 }
995
996 /* Don't backoff past cutoff. */
997 if (client->interval > config->backoff_cutoff)
998 client->interval = ((config->backoff_cutoff / 2)
999 + ((arc4random() >> 2) %
1000 config->backoff_cutoff));
1001 } else if (!client->interval)
1002 client->interval = config->initial_interval;
1003
1004 /* If the backoff would take us to the panic timeout, just use that
1005 as the interval. */
1006 if (cur_time + client->interval >
1007 client->first_sending + config->timeout)
1008 client->interval = (client->first_sending +
1009 config->timeout) - cur_time + 1;
1010
1011 /* Record the number of seconds since we started sending. */
1012 if (interval < 65536)
1013 client->packet.secs = htons(interval);
1014 else
1015 client->packet.secs = htons(65535);
1016 client->secs = client->packet.secs;
1017
1018 note("DHCPDISCOVER on %s to %s port %d interval %ld",
1019 ifi->name, inet_ntoa(sockaddr_broadcast.sin_addr),
1020 ntohs(sockaddr_broadcast.sin_port), client->interval);
1021
1022 send_packet(inaddr_any, &sockaddr_broadcast, NULL);
1023
1024 set_timeout_interval(client->interval, send_discover);
1025 }
1026
1027 /*
1028 * state_panic gets called if we haven't received any offers in a preset
1029 * amount of time. When this happens, we try to use existing leases
1030 * that haven't yet expired, and failing that, we call the client script
1031 * and hope it can do something.
1032 */
1033 void
1034 state_panic(void)
1035 {
1036 struct client_lease *loop = client->active;
1037 struct client_lease *lp;
1038 time_t cur_time;
1039
1040 note("No DHCPOFFERS received.");
1041
1042 /* We may not have an active lease, but we may have some
1043 predefined leases that we can try. */
1044 if (!client->active && client->leases)
1045 goto activate_next;
1046
1047 /* Run through the list of leases and see if one can be used. */
1048 time(&cur_time);
1049 while (client->active) {
1050 if (client->active->expiry > cur_time) {
1051 note("Trying recorded lease %s",
1052 piaddr(client->active->address));
1053 /* Run the client script with the existing
1054 parameters. */
1055 script_init("TIMEOUT");
1056 script_write_params("new_", client->active);
1057
1058 /* If the old lease is still good and doesn't
1059 yet need renewal, go into BOUND state and
1060 timeout at the renewal time. */
1061 if (!script_go()) {
1062 if (cur_time < client->active->renewal) {
1063 client->state = S_BOUND;
1064 note("bound: renewal in %lld seconds.",
1065 (long long)(client->active->renewal
1066 - cur_time));
1067 set_timeout(client->active->renewal,
1068 state_bound);
1069 } else {
1070 client->state = S_BOUND;
1071 note("bound: immediate renewal.");
1072 state_bound();
1073 }
1074 return;
1075 }
1076 }
1077
1078 /* If there are no other leases, give up. */
1079 if (!client->leases) {
1080 client->leases = client->active;
1081 client->active = NULL;
1082 break;
1083 }
1084
1085 activate_next:
1086 /* Otherwise, put the active lease at the end of the
1087 lease list, and try another lease.. */
1088 for (lp = client->leases; lp->next; lp = lp->next)
1089 ;
1090 lp->next = client->active;
1091 if (lp->next)
1092 lp->next->next = NULL;
1093 client->active = client->leases;
1094 client->leases = client->leases->next;
1095
1096 /* If we already tried this lease, we've exhausted the
1097 set of leases, so we might as well give up for
1098 now. */
1099 if (client->active == loop)
1100 break;
1101 else if (!loop)
1102 loop = client->active;
1103 }
1104
1105 /* No leases were available, or what was available didn't work, so
1106 tell the shell script that we failed to allocate an address,
1107 and try again later. */
1108 note("No working leases in persistent database - sleeping.");
1109 script_init("FAIL");
1110 script_go();
1111 client->state = S_INIT;
1112 set_timeout_interval(config->retry_interval, state_init);
1113 }
1114
1115 void
1116 send_request(void)
1117 {
1118 struct sockaddr_in destination;
1119 struct in_addr from;
1120 time_t cur_time;
1121 int interval;
1122
1123 time(&cur_time);
1124
1125 /* Figure out how long it's been since we started transmitting. */
1126 interval = (int)(cur_time - client->first_sending);
1127
1128 /* If we're in the INIT-REBOOT or REQUESTING state and we're
1129 past the reboot timeout, go to INIT and see if we can
1130 DISCOVER an address... */
1131 /* XXX In the INIT-REBOOT state, if we don't get an ACK, it
1132 means either that we're on a network with no DHCP server,
1133 or that our server is down. In the latter case, assuming
1134 that there is a backup DHCP server, DHCPDISCOVER will get
1135 us a new address, but we could also have successfully
1136 reused our old address. In the former case, we're hosed
1137 anyway. This is not a win-prone situation. */
1138 if ((client->state == S_REBOOTING ||
1139 client->state == S_REQUESTING) &&
1140 interval > config->reboot_timeout) {
1141 client->state = S_INIT;
1142 cancel_timeout();
1143 state_init();
1144 return;
1145 }
1146
1147 /* If the lease has expired, relinquish the address and go back
1148 to the INIT state. */
1149 if (client->state != S_REQUESTING &&
1150 cur_time > client->active->expiry) {
1151 /* Run the client script with the new parameters. */
1152 script_init("EXPIRE");
1153 script_write_params("old_", client->active);
1154 script_go();
1155
1156 client->state = S_INIT;
1157 state_init();
1158 return;
1159 }
1160
1161 /* Do the exponential backoff... */
1162 if (!client->interval)
1163 client->interval = config->initial_interval;
1164 else
1165 client->interval += ((arc4random() >> 2) %
1166 (2 * client->interval));
1167
1168 /* Don't backoff past cutoff. */
1169 if (client->interval > config->backoff_cutoff)
1170 client->interval = ((config->backoff_cutoff / 2) +
1171 ((arc4random() >> 2) % client->interval));
1172
1173 /* If the backoff would take us to the expiry time, just set the
1174 timeout to the expiry time. */
1175 if (client->state != S_REQUESTING && cur_time + client->interval >
1176 client->active->expiry)
1177 client->interval = client->active->expiry - cur_time + 1;
1178
1179 /* If the lease T2 time has elapsed, or if we're not yet bound,
1180 broadcast the DHCPREQUEST rather than unicasting. */
1181 memset(&destination, 0, sizeof(destination));
1182 if (client->state == S_REQUESTING ||
1183 client->state == S_REBOOTING ||
1184 cur_time > client->active->rebind)
1185 destination.sin_addr.s_addr = INADDR_BROADCAST;
1186 else
1187 memcpy(&destination.sin_addr.s_addr, client->destination.iabuf,
1188 sizeof(destination.sin_addr.s_addr));
1189 destination.sin_port = htons(REMOTE_PORT);
1190 destination.sin_family = AF_INET;
1191 destination.sin_len = sizeof(destination);
1192
1193 if (client->state != S_REQUESTING)
1194 memcpy(&from, client->active->address.iabuf, sizeof(from));
1195 else
1196 from.s_addr = INADDR_ANY;
1197
1198 /* Record the number of seconds since we started sending. */
1199 if (client->state == S_REQUESTING)
1200 client->packet.secs = client->secs;
1201 else {
1202 if (interval < 65536)
1203 client->packet.secs = htons(interval);
1204 else
1205 client->packet.secs = htons(65535);
1206 }
1207
1208 note("DHCPREQUEST on %s to %s port %d", ifi->name,
1209 inet_ntoa(destination.sin_addr), ntohs(destination.sin_port));
1210
1211 send_packet(from, &destination, NULL);
1212
1213 set_timeout_interval(client->interval, send_request);
1214 }
1215
1216 void
1217 send_decline(void)
1218 {
1219 note("DHCPDECLINE on %s to %s port %d", ifi->name,
1220 inet_ntoa(sockaddr_broadcast.sin_addr),
1221 ntohs(sockaddr_broadcast.sin_port));
1222
1223 send_packet(inaddr_any, &sockaddr_broadcast, NULL);
1224 }
1225
1226 void
1227 make_discover(struct client_lease *lease)
1228 {
1229 unsigned char discover = DHCPDISCOVER;
1230 struct option_data options[256];
1231 int i;
1232
1233 memset(options, 0, sizeof(options));
1234 memset(&client->packet, 0, sizeof(client->packet));
1235
1236 /* Set DHCP_MESSAGE_TYPE to DHCPDISCOVER */
1237 i = DHO_DHCP_MESSAGE_TYPE;
1238 options[i].data = &discover;
1239 options[i].len = sizeof(discover);
1240
1241 /* Request the options we want */
1242 i = DHO_DHCP_PARAMETER_REQUEST_LIST;
1243 options[i].data = config->requested_options;
1244 options[i].len = config->requested_option_count;
1245
1246 /* If we had an address, try to get it again. */
1247 if (lease) {
1248 client->requested_address = lease->address;
1249 i = DHO_DHCP_REQUESTED_ADDRESS;
1250 options[i].data = lease->address.iabuf;
1251 options[i].len = lease->address.len;
1252 } else
1253 client->requested_address.len = 0;
1254
1255 /* Send any options requested in the config file. */
1256 for (i = 0; i < 256; i++)
1257 if (!options[i].data &&
1258 config->send_options[i].data) {
1259 options[i].data = config->send_options[i].data;
1260 options[i].len = config->send_options[i].len;
1261 }
1262
1263 /* Set up the option buffer to fit in a minimal UDP packet. */
1264 i = cons_options(options);
1265 if (i == -1 || client->packet.options[i] != DHO_END)
1266 error("options do not fit in DHCPDISCOVER packet.");
1267 client->packet_length = DHCP_FIXED_NON_UDP+i+1;
1268 if (client->packet_length < BOOTP_MIN_LEN)
1269 client->packet_length = BOOTP_MIN_LEN;
1270
1271 client->packet.op = BOOTREQUEST;
1272 client->packet.htype = ifi->hw_address.htype;
1273 client->packet.hlen = ifi->hw_address.hlen;
1274 client->packet.hops = 0;
1275 client->packet.xid = arc4random();
1276 client->packet.secs = 0; /* filled in by send_discover. */
1277 client->packet.flags = 0;
1278
1279 memset(&client->packet.ciaddr, 0, sizeof(client->packet.ciaddr));
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_request(struct client_lease * lease)
1289 {
1290 unsigned char request = DHCPREQUEST;
1291 struct option_data options[256];
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 DHCPREQUEST */
1298 i = DHO_DHCP_MESSAGE_TYPE;
1299 options[i].data = &request;
1300 options[i].len = sizeof(request);
1301
1302 /* Request the options we want */
1303 i = DHO_DHCP_PARAMETER_REQUEST_LIST;
1304 options[i].data = config->requested_options;
1305 options[i].len = config->requested_option_count;
1306
1307 /* If we are requesting an address that hasn't yet been assigned
1308 to us, use the DHCP Requested Address option. */
1309 if (client->state == S_REQUESTING) {
1310 /* Send back the server identifier... */
1311 i = DHO_DHCP_SERVER_IDENTIFIER;
1312 options[i].data = lease->options[i].data;
1313 options[i].len = lease->options[i].len;
1314 }
1315 if (client->state == S_REQUESTING ||
1316 client->state == S_REBOOTING) {
1317 client->requested_address = lease->address;
1318 i = DHO_DHCP_REQUESTED_ADDRESS;
1319 options[i].data = lease->address.iabuf;
1320 options[i].len = lease->address.len;
1321 } else
1322 client->requested_address.len = 0;
1323
1324 /* Send any options requested in the config file. */
1325 for (i = 0; i < 256; i++)
1326 if (!options[i].data && config->send_options[i].data) {
1327 options[i].data = config->send_options[i].data;
1328 options[i].len = config->send_options[i].len;
1329 }
1330
1331 /* Set up the option buffer to fit in a minimal UDP packet. */
1332 i = cons_options(options);
1333 if (i == -1 || client->packet.options[i] != DHO_END)
1334 error("options do not fit in DHCPREQUEST packet.");
1335 client->packet_length = DHCP_FIXED_NON_UDP+i+1;
1336 if (client->packet_length < BOOTP_MIN_LEN)
1337 client->packet_length = BOOTP_MIN_LEN;
1338
1339 client->packet.op = BOOTREQUEST;
1340 client->packet.htype = ifi->hw_address.htype;
1341 client->packet.hlen = ifi->hw_address.hlen;
1342 client->packet.hops = 0;
1343 client->packet.xid = client->xid;
1344 client->packet.secs = 0; /* Filled in by send_request. */
1345 client->packet.flags = 0;
1346
1347 /* If we own the address we're requesting, put it in ciaddr;
1348 otherwise set ciaddr to zero. */
1349 if (client->state == S_BOUND ||
1350 client->state == S_RENEWING ||
1351 client->state == S_REBINDING) {
1352 memcpy(&client->packet.ciaddr,
1353 lease->address.iabuf, lease->address.len);
1354 } else {
1355 memset(&client->packet.ciaddr, 0,
1356 sizeof(client->packet.ciaddr));
1357 }
1358
1359 memset(&client->packet.yiaddr, 0, sizeof(client->packet.yiaddr));
1360 memset(&client->packet.siaddr, 0, sizeof(client->packet.siaddr));
1361 memset(&client->packet.giaddr, 0, sizeof(client->packet.giaddr));
1362 memcpy(client->packet.chaddr, ifi->hw_address.haddr,
1363 ifi->hw_address.hlen);
1364 }
1365
1366 void
1367 make_decline(struct client_lease *lease)
1368 {
1369 struct option_data options[256];
1370 unsigned char decline = DHCPDECLINE;
1371 int i;
1372
1373 memset(options, 0, sizeof(options));
1374 memset(&client->packet, 0, sizeof(client->packet));
1375
1376 /* Set DHCP_MESSAGE_TYPE to DHCPDECLINE */
1377 i = DHO_DHCP_MESSAGE_TYPE;
1378 options[i].data = &decline;
1379 options[i].len = sizeof(decline);
1380
1381 /* Send back the server identifier... */
1382 i = DHO_DHCP_SERVER_IDENTIFIER;
1383 options[i].data = lease->options[i].data;
1384 options[i].len = lease->options[i].len;
1385
1386 /* Send back the address we're declining. */
1387 i = DHO_DHCP_REQUESTED_ADDRESS;
1388 options[i].data = lease->address.iabuf;
1389 options[i].len = lease->address.len;
1390
1391 /* Send the uid if the user supplied one. */
1392 i = DHO_DHCP_CLIENT_IDENTIFIER;
1393 if (config->send_options[i].len) {
1394 options[i].data = config->send_options[i].data;
1395 options[i].len = config->send_options[i].len;
1396 }
1397
1398 /* Set up the option buffer to fit in a minimal UDP packet. */
1399 i = cons_options(options);
1400 if (i == -1 || client->packet.options[i] != DHO_END)
1401 error("options do not fit in DHCPDECLINE packet.");
1402 client->packet_length = DHCP_FIXED_NON_UDP+i+1;
1403 if (client->packet_length < BOOTP_MIN_LEN)
1404 client->packet_length = BOOTP_MIN_LEN;
1405
1406 client->packet.op = BOOTREQUEST;
1407 client->packet.htype = ifi->hw_address.htype;
1408 client->packet.hlen = ifi->hw_address.hlen;
1409 client->packet.hops = 0;
1410 client->packet.xid = client->xid;
1411 client->packet.secs = 0; /* Filled in by send_request. */
1412 client->packet.flags = 0;
1413
1414 /* ciaddr must always be zero. */
1415 memset(&client->packet.ciaddr, 0, sizeof(client->packet.ciaddr));
1416 memset(&client->packet.yiaddr, 0, sizeof(client->packet.yiaddr));
1417 memset(&client->packet.siaddr, 0, sizeof(client->packet.siaddr));
1418 memset(&client->packet.giaddr, 0, sizeof(client->packet.giaddr));
1419 memcpy(client->packet.chaddr, ifi->hw_address.haddr,
1420 ifi->hw_address.hlen);
1421 }
1422
1423 void
1424 free_client_lease(struct client_lease *lease)
1425 {
1426 int i;
1427
1428 if (lease->server_name)
1429 free(lease->server_name);
1430 if (lease->filename)
1431 free(lease->filename);
1432 for (i = 0; i < 256; i++) {
1433 if (lease->options[i].len)
1434 free(lease->options[i].data);
1435 }
1436 free(lease);
1437 }
1438
1439 void
1440 rewrite_client_leases(void)
1441 {
1442 struct client_lease *lp;
1443
1444 if (!leaseFile) /* XXX */
1445 error("lease file not open");
1446
1447 fflush(leaseFile);
1448 rewind(leaseFile);
1449
1450 for (lp = client->leases; lp; lp = lp->next) {
1451 if (client->active && addr_eq(lp->address,
1452 client->active->address))
1453 continue;
1454 write_client_lease(lp);
1455 }
1456
1457 if (client->active)
1458 write_client_lease(client->active);
1459
1460 fflush(leaseFile);
1461 ftruncate(fileno(leaseFile), ftello(leaseFile));
1462 fsync(fileno(leaseFile));
1463 }
1464
1465 void
1466 write_client_lease(struct client_lease *lease)
1467 {
1468 struct tm *t;
1469 int i;
1470
1471 /* If the lease came from the config file, we don't need to stash
1472 a copy in the lease database. */
1473 if (lease->is_static)
1474 return;
1475
1476 if (!leaseFile) /* XXX */
1477 error("lease file not open");
1478
1479 fprintf(leaseFile, "lease {\n");
1480 if (lease->is_bootp)
1481 fprintf(leaseFile, " bootp;\n");
1482 fprintf(leaseFile, " interface \"%s\";\n", ifi->name);
1483 fprintf(leaseFile, " fixed-address %s;\n", piaddr(lease->address));
1484 if (lease->filename)
1485 fprintf(leaseFile, " filename \"%s\";\n", lease->filename);
1486 if (lease->server_name)
1487 fprintf(leaseFile, " server-name \"%s\";\n",
1488 lease->server_name);
1489 for (i = 0; i < 256; i++)
1490 if (lease->options[i].len)
1491 fprintf(leaseFile, " option %s %s;\n",
1492 dhcp_options[i].name,
1493 pretty_print_option(i, &lease->options[i], 1));
1494
1495 t = gmtime(&lease->renewal);
1496 fprintf(leaseFile, " renew %d %d/%d/%d %02d:%02d:%02d;\n",
1497 t->tm_wday, t->tm_year + 1900, t->tm_mon + 1, t->tm_mday,
1498 t->tm_hour, t->tm_min, t->tm_sec);
1499 t = gmtime(&lease->rebind);
1500 fprintf(leaseFile, " rebind %d %d/%d/%d %02d:%02d:%02d;\n",
1501 t->tm_wday, t->tm_year + 1900, t->tm_mon + 1, t->tm_mday,
1502 t->tm_hour, t->tm_min, t->tm_sec);
1503 t = gmtime(&lease->expiry);
1504 fprintf(leaseFile, " expire %d %d/%d/%d %02d:%02d:%02d;\n",
1505 t->tm_wday, t->tm_year + 1900, t->tm_mon + 1, t->tm_mday,
1506 t->tm_hour, t->tm_min, t->tm_sec);
1507 fprintf(leaseFile, "}\n");
1508 fflush(leaseFile);
1509 }
1510
1511 void
1512 script_init(char *reason)
1513 {
1514 size_t len;
1515 struct imsg_hdr hdr;
1516 struct buf *buf;
1517
1518 hdr.code = IMSG_SCRIPT_INIT;
1519 hdr.len = sizeof(struct imsg_hdr) + sizeof(size_t) + strlen(reason);
1520 buf = buf_open(hdr.len);
1521
1522 buf_add(buf, &hdr, sizeof(hdr));
1523 len = strlen(reason);
1524 buf_add(buf, &len, sizeof(len));
1525 buf_add(buf, reason, len);
1526
1527 buf_close(privfd, buf);
1528 }
1529
1530 void
1531 priv_script_init(char *reason)
1532 {
1533 client->scriptEnvsize = 100;
1534 if (client->scriptEnv == NULL)
1535 client->scriptEnv =
1536 calloc(client->scriptEnvsize, sizeof(char *));
1537 if (client->scriptEnv == NULL)
1538 error("script_init: no memory for environment");
1539
1540 client->scriptEnv[0] = strdup(CLIENT_PATH);
1541 if (client->scriptEnv[0] == NULL)
1542 error("script_init: no memory for environment");
1543
1544 client->scriptEnv[1] = NULL;
1545
1546 script_set_env("", "interface", ifi->name);
1547
1548 script_set_env("", "reason", reason);
1549 }
1550
1551 void
1552 priv_script_write_params(char *prefix, struct client_lease *lease)
1553 {
1554 char buf[256];
1555 struct option_data o;
1556 int i;
1557
1558 script_set_env(prefix, "ip_address", piaddr(lease->address));
1559
1560 if (lease->options[DHO_SUBNET_MASK].len &&
1561 (lease->options[DHO_SUBNET_MASK].len <
1562 sizeof(lease->address.iabuf))) {
1563 struct iaddr netmask, subnet, broadcast;
1564
1565 memcpy(netmask.iabuf, lease->options[DHO_SUBNET_MASK].data,
1566 lease->options[DHO_SUBNET_MASK].len);
1567 netmask.len = lease->options[DHO_SUBNET_MASK].len;
1568
1569 subnet = subnet_number(lease->address, netmask);
1570 if (subnet.len) {
1571 script_set_env(prefix, "network_number",
1572 piaddr(subnet));
1573 if (!lease->options[DHO_BROADCAST_ADDRESS].len) {
1574 broadcast = broadcast_addr(subnet, netmask);
1575 if (broadcast.len)
1576 script_set_env(prefix,
1577 "broadcast_address",
1578 piaddr(broadcast));
1579 }
1580 }
1581 }
1582
1583 if (lease->filename)
1584 script_set_env(prefix, "filename", lease->filename);
1585 if (lease->server_name)
1586 script_set_env(prefix, "server_name",
1587 lease->server_name);
1588
1589 for (i = 0; i < 256; i++) {
1590 if (!dhcp_option_ev_name(buf, sizeof(buf), &dhcp_options[i]))
1591 continue;
1592
1593 switch (config->default_actions[i]) {
1594 case ACTION_IGNORE:
1595 break;
1596
1597 case ACTION_DEFAULT:
1598 if (lease->options[i].len)
1599 script_set_env(prefix, buf,
1600 pretty_print_option(i, &lease->options[i],
1601 0));
1602 else if (config->defaults[i].len)
1603 script_set_env(prefix, buf,
1604 pretty_print_option(i, &config->defaults[i],
1605 0));
1606 break;
1607
1608 case ACTION_SUPERSEDE:
1609 if (config->defaults[i].len)
1610 script_set_env(prefix, buf,
1611 pretty_print_option(i, &config->defaults[i],
1612 0));
1613 break;
1614
1615 case ACTION_PREPEND:
1616 o.len = config->defaults[i].len + lease->options[i].len;
1617 if (o.len > 0) {
1618 o.data = calloc(1, o.len);
1619 if (o.data == NULL)
1620 error("no space to prepend '%s' to %s",
1621 config->defaults[i].data,
1622 dhcp_options[i].name);
1623 memcpy(o.data, config->defaults[i].data,
1624 config->defaults[i].len);
1625 memcpy(o.data + config->defaults[i].len,
1626 lease->options[i].data,
1627 lease->options[i].len);
1628 script_set_env(prefix, buf,
1629 pretty_print_option(i, &o, 0));
1630 free(o.data);
1631 }
1632 break;
1633
1634 case ACTION_APPEND:
1635 o.len = config->defaults[i].len + lease->options[i].len;
1636 if (o.len > 0) {
1637 o.data = calloc(1, o.len);
1638 if (o.data == NULL)
1639 error("no space to append '%s' to %s",
1640 config->defaults[i].data,
1641 dhcp_options[i].name);
1642 memcpy(o.data, lease->options[i].data,
1643 lease->options[i].len);
1644 memcpy(o.data + lease->options[i].len,
1645 config->defaults[i].data,
1646 config->defaults[i].len);
1647 script_set_env(prefix, buf,
1648 pretty_print_option(i, &o, 0));
1649 free(o.data);
1650 }
1651 break;
1652 }
1653 }
1654
1655 snprintf(buf, sizeof(buf), "%d", (int)lease->expiry);
1656 script_set_env(prefix, "expiry", buf);
1657 }
1658
1659 void
1660 script_write_params(char *prefix, struct client_lease *lease)
1661 {
1662 size_t fn_len = 0, sn_len = 0, pr_len = 0;
1663 struct imsg_hdr hdr;
1664 struct buf *buf;
1665 int i;
1666
1667 if (lease->filename != NULL)
1668 fn_len = strlen(lease->filename);
1669 if (lease->server_name != NULL)
1670 sn_len = strlen(lease->server_name);
1671 if (prefix != NULL)
1672 pr_len = strlen(prefix);
1673
1674 hdr.code = IMSG_SCRIPT_WRITE_PARAMS;
1675 hdr.len = sizeof(hdr) + sizeof(struct client_lease) +
1676 sizeof(size_t) + fn_len + sizeof(size_t) + sn_len +
1677 sizeof(size_t) + pr_len;
1678
1679 for (i = 0; i < 256; i++)
1680 hdr.len += sizeof(int) + lease->options[i].len;
1681
1682 scripttime = time(NULL);
1683
1684 buf = buf_open(hdr.len);
1685
1686 buf_add(buf, &hdr, sizeof(hdr));
1687 buf_add(buf, lease, sizeof(struct client_lease));
1688 buf_add(buf, &fn_len, sizeof(fn_len));
1689 buf_add(buf, lease->filename, fn_len);
1690 buf_add(buf, &sn_len, sizeof(sn_len));
1691 buf_add(buf, lease->server_name, sn_len);
1692 buf_add(buf, &pr_len, sizeof(pr_len));
1693 buf_add(buf, prefix, pr_len);
1694
1695 for (i = 0; i < 256; i++) {
1696 buf_add(buf, &lease->options[i].len,
1697 sizeof(lease->options[i].len));
1698 buf_add(buf, lease->options[i].data,
1699 lease->options[i].len);
1700 }
1701
1702 buf_close(privfd, buf);
1703 }
1704
1705 int
1706 script_go(void)
1707 {
1708 struct imsg_hdr hdr;
1709 struct buf *buf;
1710 int ret;
1711
1712 scripttime = time(NULL);
1713
1714 hdr.code = IMSG_SCRIPT_GO;
1715 hdr.len = sizeof(struct imsg_hdr);
1716
1717 buf = buf_open(hdr.len);
1718
1719 buf_add(buf, &hdr, sizeof(hdr));
1720 buf_close(privfd, buf);
1721
1722 bzero(&hdr, sizeof(hdr));
1723 buf_read(privfd, &hdr, sizeof(hdr));
1724 if (hdr.code != IMSG_SCRIPT_GO_RET)
1725 error("unexpected msg type %u", hdr.code);
1726 if (hdr.len != sizeof(hdr) + sizeof(int))
1727 error("received corrupted message");
1728 buf_read(privfd, &ret, sizeof(ret));
1729
1730 return (ret);
1731 }
1732
1733 int
1734 priv_script_go(void)
1735 {
1736 char *scriptName, *argv[2], **envp;
1737 int pid, wpid, wstatus;
1738
1739 scripttime = time(NULL);
1740
1741 scriptName = config->script_name;
1742 envp = client->scriptEnv;
1743
1744 argv[0] = scriptName;
1745 argv[1] = NULL;
1746
1747 pid = fork();
1748 if (pid < 0) {
1749 error("fork: %m");
1750 wstatus = 0;
1751 } else if (pid) {
1752 do {
1753 wpid = wait(&wstatus);
1754 } while (wpid != pid && wpid > 0);
1755 if (wpid < 0) {
1756 error("wait: %m");
1757 wstatus = 0;
1758 }
1759 } else {
1760 execve(scriptName, argv, envp);
1761 error("execve (%s, ...): %m", scriptName);
1762 }
1763
1764 script_flush_env();
1765
1766 return (WEXITSTATUS(wstatus));
1767 }
1768
1769 void
1770 script_set_env(const char *prefix, const char *name, const char *value)
1771 {
1772 int i, j, namelen;
1773
1774 /* No `` or $() command substitution allowed in environment values! */
1775 for (j = 0; j < strlen(value); j++)
1776 switch (value[j]) {
1777 case '`':
1778 case '$':
1779 warning("illegal character (%c) in value '%s'",
1780 value[j], value);
1781 /* Ignore this option */
1782 return;
1783 }
1784
1785 namelen = strlen(name);
1786
1787 for (i = 0; client->scriptEnv[i]; i++)
1788 if (strncmp(client->scriptEnv[i], name, namelen) == 0 &&
1789 client->scriptEnv[i][namelen] == '=')
1790 break;
1791
1792 if (client->scriptEnv[i])
1793 /* Reuse the slot. */
1794 free(client->scriptEnv[i]);
1795 else {
1796 /* New variable. Expand if necessary. */
1797 if (i >= client->scriptEnvsize - 1) {
1798 char **newscriptEnv;
1799 int newscriptEnvsize = client->scriptEnvsize + 50;
1800
1801 newscriptEnv = realloc(client->scriptEnv,
1802 newscriptEnvsize);
1803 if (newscriptEnv == NULL) {
1804 free(client->scriptEnv);
1805 client->scriptEnv = NULL;
1806 client->scriptEnvsize = 0;
1807 error("script_set_env: no memory for variable");
1808 }
1809 client->scriptEnv = newscriptEnv;
1810 client->scriptEnvsize = newscriptEnvsize;
1811 }
1812 /* need to set the NULL pointer at end of array beyond
1813 the new slot. */
1814 client->scriptEnv[i + 1] = NULL;
1815 }
1816 /* Allocate space and format the variable in the appropriate slot. */
1817 client->scriptEnv[i] = malloc(strlen(prefix) + strlen(name) + 1 +
1818 strlen(value) + 1);
1819 if (client->scriptEnv[i] == NULL)
1820 error("script_set_env: no memory for variable assignment");
1821 snprintf(client->scriptEnv[i], strlen(prefix) + strlen(name) +
1822 1 + strlen(value) + 1, "%s%s=%s", prefix, name, value);
1823 }
1824
1825 void
1826 script_flush_env(void)
1827 {
1828 int i;
1829
1830 for (i = 0; client->scriptEnv[i]; i++) {
1831 free(client->scriptEnv[i]);
1832 client->scriptEnv[i] = NULL;
1833 }
1834 client->scriptEnvsize = 0;
1835 }
1836
1837 int
1838 dhcp_option_ev_name(char *buf, size_t buflen, const struct option *option)
1839 {
1840 size_t i;
1841
1842 for (i = 0; option->name[i]; i++) {
1843 if (i + 1 == buflen)
1844 return 0;
1845 if (option->name[i] == '-')
1846 buf[i] = '_';
1847 else
1848 buf[i] = option->name[i];
1849 }
1850
1851 buf[i] = 0;
1852 return 1;
1853 }
1854
1855 void
1856 go_daemon(void)
1857 {
1858 char buf[256];
1859 int fd;
1860
1861 /*
1862 * Only once
1863 */
1864 if (no_daemon == 2)
1865 return;
1866
1867 /*
1868 * Setup pidfile, kill any dhclient already running for this
1869 * interface.
1870 */
1871 snprintf(buf, sizeof(buf), "/var/run/dhclient.%s.pid", orig_ifname);
1872 fd = open(buf, O_RDWR|O_CREAT, 0644);
1873 if (fd >= 0) {
1874 if (killclient(fd)) {
1875 fprintf(stderr,
1876 "starting dhclient on %s\n",
1877 orig_ifname);
1878 } else {
1879 fprintf(stderr,
1880 "restarting dhclient on %s\n",
1881 orig_ifname);
1882 }
1883 }
1884
1885 /*
1886 * Daemonize if requested
1887 */
1888 if (no_daemon == 0) {
1889 /* Stop logging to stderr... */
1890 log_perror = 0;
1891
1892 if (daemon(1, 0) == -1)
1893 error("daemon");
1894
1895 /* we are chrooted, daemon(3) fails to open /dev/null */
1896 if (nullfd != -1) {
1897 dup2(nullfd, STDIN_FILENO);
1898 dup2(nullfd, STDOUT_FILENO);
1899 dup2(nullfd, STDERR_FILENO);
1900 close(nullfd);
1901 nullfd = -1;
1902 }
1903 }
1904
1905 /*
1906 * No further daemonizations, write out pid file and lock.
1907 */
1908 no_daemon = 2;
1909 if (fd >= 0) {
1910 lseek(fd, 0L, SEEK_SET);
1911 ftruncate(fd, 0);
1912 snprintf(buf, sizeof(buf), "%ld\n", (long)getpid());
1913 write(fd, buf, strlen(buf));
1914 flock(fd, LOCK_EX);
1915 /* leave descriptor open and locked */
1916 }
1917 }
1918
1919 int
1920 check_option(struct client_lease *l, int option)
1921 {
1922 char *opbuf;
1923 char *sbuf;
1924
1925 /* we use this, since this is what gets passed to dhclient-script */
1926
1927 opbuf = pretty_print_option(option, &l->options[option], 0);
1928
1929 sbuf = option_as_string(option, l->options[option].data,
1930 l->options[option].len);
1931
1932 switch (option) {
1933 case DHO_SUBNET_MASK:
1934 case DHO_SWAP_SERVER:
1935 case DHO_BROADCAST_ADDRESS:
1936 case DHO_DHCP_SERVER_IDENTIFIER:
1937 case DHO_ROUTER_SOLICITATION_ADDRESS:
1938 case DHO_DHCP_REQUESTED_ADDRESS:
1939 if (ipv4addrs(opbuf) == 0) {
1940 warning("Invalid IP address in option %s: %s",
1941 dhcp_options[option].name, opbuf);
1942 return (0);
1943 }
1944 if (l->options[option].len != 4) { /* RFC 2132 */
1945 warning("warning: Only 1 IP address allowed in "
1946 "%s option; length %d, must be 4",
1947 dhcp_options[option].name,
1948 l->options[option].len);
1949 l->options[option].len = 4;
1950 }
1951 return (1);
1952 case DHO_TIME_SERVERS:
1953 case DHO_NAME_SERVERS:
1954 case DHO_ROUTERS:
1955 case DHO_DOMAIN_NAME_SERVERS:
1956 case DHO_LOG_SERVERS:
1957 case DHO_COOKIE_SERVERS:
1958 case DHO_LPR_SERVERS:
1959 case DHO_IMPRESS_SERVERS:
1960 case DHO_RESOURCE_LOCATION_SERVERS:
1961 case DHO_NIS_SERVERS:
1962 case DHO_NTP_SERVERS:
1963 case DHO_NETBIOS_NAME_SERVERS:
1964 case DHO_NETBIOS_DD_SERVER:
1965 case DHO_FONT_SERVERS:
1966 if (ipv4addrs(opbuf) == 0) {
1967 warning("Invalid IP address in option %s: %s",
1968 dhcp_options[option].name, opbuf);
1969 return (0);
1970 }
1971 return (1);
1972 case DHO_HOST_NAME:
1973 case DHO_DOMAIN_NAME:
1974 case DHO_NIS_DOMAIN:
1975 if (!res_hnok(sbuf)) {
1976 warning("Bogus Host Name option %d: %s (%s)", option,
1977 sbuf, opbuf);
1978 l->options[option].len = 0;
1979 free(l->options[option].data);
1980 }
1981 return (1);
1982 case DHO_PAD:
1983 case DHO_TIME_OFFSET:
1984 case DHO_BOOT_SIZE:
1985 case DHO_MERIT_DUMP:
1986 case DHO_ROOT_PATH:
1987 case DHO_EXTENSIONS_PATH:
1988 case DHO_IP_FORWARDING:
1989 case DHO_NON_LOCAL_SOURCE_ROUTING:
1990 case DHO_POLICY_FILTER:
1991 case DHO_MAX_DGRAM_REASSEMBLY:
1992 case DHO_DEFAULT_IP_TTL:
1993 case DHO_PATH_MTU_AGING_TIMEOUT:
1994 case DHO_PATH_MTU_PLATEAU_TABLE:
1995 case DHO_INTERFACE_MTU:
1996 case DHO_ALL_SUBNETS_LOCAL:
1997 case DHO_PERFORM_MASK_DISCOVERY:
1998 case DHO_MASK_SUPPLIER:
1999 case DHO_ROUTER_DISCOVERY:
2000 case DHO_STATIC_ROUTES:
2001 case DHO_TRAILER_ENCAPSULATION:
2002 case DHO_ARP_CACHE_TIMEOUT:
2003 case DHO_IEEE802_3_ENCAPSULATION:
2004 case DHO_DEFAULT_TCP_TTL:
2005 case DHO_TCP_KEEPALIVE_INTERVAL:
2006 case DHO_TCP_KEEPALIVE_GARBAGE:
2007 case DHO_VENDOR_ENCAPSULATED_OPTIONS:
2008 case DHO_NETBIOS_NODE_TYPE:
2009 case DHO_NETBIOS_SCOPE:
2010 case DHO_X_DISPLAY_MANAGER:
2011 case DHO_DHCP_LEASE_TIME:
2012 case DHO_DHCP_OPTION_OVERLOAD:
2013 case DHO_DHCP_MESSAGE_TYPE:
2014 case DHO_DHCP_PARAMETER_REQUEST_LIST:
2015 case DHO_DHCP_MESSAGE:
2016 case DHO_DHCP_MAX_MESSAGE_SIZE:
2017 case DHO_DHCP_RENEWAL_TIME:
2018 case DHO_DHCP_REBINDING_TIME:
2019 case DHO_DHCP_CLASS_IDENTIFIER:
2020 case DHO_DHCP_CLIENT_IDENTIFIER:
2021 case DHO_DHCP_USER_CLASS_ID:
2022 case DHO_TFTP_SERVER:
2023 case DHO_END:
2024 return (1);
2025 case DHO_CLASSLESS_ROUTES:
2026 return (check_classless_option(l->options[option].data,
2027 l->options[option].len));
2028 default:
2029 if (!unknown_ok)
2030 warning("unknown dhcp option value 0x%x", option);
2031 return (unknown_ok);
2032 }
2033 }
2034
2035 /* RFC 3442 The Classless Static Routes option checks */
2036 int
2037 check_classless_option(unsigned char *data, int len)
2038 {
2039 int i = 0;
2040 unsigned char width;
2041 in_addr_t addr, mask;
2042
2043 if (len < 5) {
2044 warning("Too small length: %d", len);
2045 return (0);
2046 }
2047 while(i < len) {
2048 width = data[i++];
2049 if (width == 0) {
2050 i += 4;
2051 continue;
2052 } else if (width < 9) {
2053 addr = (in_addr_t)(data[i] << 24);
2054 i += 1;
2055 } else if (width < 17) {
2056 addr = (in_addr_t)(data[i] << 24) +
2057 (in_addr_t)(data[i + 1] << 16);
2058 i += 2;
2059 } else if (width < 25) {
2060 addr = (in_addr_t)(data[i] << 24) +
2061 (in_addr_t)(data[i + 1] << 16) +
2062 (in_addr_t)(data[i + 2] << 8);
2063 i += 3;
2064 } else if (width < 33) {
2065 addr = (in_addr_t)(data[i] << 24) +
2066 (in_addr_t)(data[i + 1] << 16) +
2067 (in_addr_t)(data[i + 2] << 8) +
2068 data[i + 3];
2069 i += 4;
2070 } else {
2071 warning("Incorrect subnet width: %d", width);
2072 return (0);
2073 }
2074 mask = (in_addr_t)(~0) << (32 - width);
2075 addr = ntohl(addr);
2076 mask = ntohl(mask);
2077
2078 /*
2079 * From RFC 3442:
2080 * ... After deriving a subnet number and subnet mask
2081 * from each destination descriptor, the DHCP client
2082 * MUST zero any bits in the subnet number where the
2083 * corresponding bit in the mask is zero...
2084 */
2085 if ((addr & mask) != addr) {
2086 addr &= mask;
2087 data[i - 1] = (unsigned char)(
2088 (addr >> (((32 - width)/8)*8)) & 0xFF);
2089 }
2090 i += 4;
2091 }
2092 if (i > len) {
2093 warning("Incorrect data length: %d (must be %d)", len, i);
2094 return (0);
2095 }
2096 return (1);
2097 }
2098
2099 int
2100 res_hnok(const char *name)
2101 {
2102 const char *dn = name;
2103 int pch = '.', ch = *dn++;
2104 int warn = 0;
2105
2106 while (ch != '\0') {
2107 int nch = *dn++;
2108
2109 if (ch == '.') {
2110 ;
2111 } else if (pch == '.' || nch == '.' || nch == '\0') {
2112 if (!isalnum(ch))
2113 return (0);
2114 } else if (!isalnum(ch) && ch != '-' && ch != '_')
2115 return (0);
2116 else if (ch == '_' && warn == 0) {
2117 warning("warning: hostname %s contains an "
2118 "underscore which violates RFC 952", name);
2119 warn++;
2120 }
2121 pch = ch, ch = nch;
2122 }
2123 return (1);
2124 }
2125
2126 /* Does buf consist only of dotted decimal ipv4 addrs?
2127 * return how many if so,
2128 * otherwise, return 0
2129 */
2130 int
2131 ipv4addrs(char * buf)
2132 {
2133 struct in_addr jnk;
2134 int count = 0;
2135
2136 while (inet_aton(buf, &jnk) == 1){
2137 count++;
2138 while (*buf == '.' || isdigit(*buf))
2139 buf++;
2140 if (*buf == '\0')
2141 return (count);
2142 while (*buf == ' ')
2143 buf++;
2144 }
2145 return (0);
2146 }
2147
2148 char *
2149 option_as_string(unsigned int code, unsigned char *data, int len)
2150 {
2151 static char optbuf[32768]; /* XXX */
2152 char *op = optbuf;
2153 int opleft = sizeof(optbuf);
2154 unsigned char *dp = data;
2155
2156 if (code > 255)
2157 error("option_as_string: bad code %d", code);
2158
2159 for (; dp < data + len; dp++) {
2160 if (!isascii(*dp) || !isprint(*dp)) {
2161 if (dp + 1 != data + len || *dp != 0) {
2162 size_t oplen;
2163 snprintf(op, opleft, "\\%03o", *dp);
2164 oplen = strlen(op);
2165 op += oplen;
2166 opleft -= oplen;
2167 }
2168 } else if (*dp == '"' || *dp == '\'' || *dp == '$' ||
2169 *dp == '`' || *dp == '\\') {
2170 *op++ = '\\';
2171 *op++ = *dp;
2172 opleft -= 2;
2173 } else {
2174 *op++ = *dp;
2175 opleft--;
2176 }
2177 }
2178 if (opleft < 1)
2179 goto toobig;
2180 *op = 0;
2181 return optbuf;
2182 toobig:
2183 warning("dhcp option too large");
2184 return "<error>";
2185 }
2186
2187 int
2188 fork_privchld(int fd, int fd2)
2189 {
2190 struct pollfd pfd[1];
2191 int nfds, pfail = 0;
2192 pid_t pid;
2193 int omask;
2194
2195 omask = sigblock(sigmask(SIGINT)|sigmask(SIGHUP));
2196 pid = fork();
2197 if (pid > 0)
2198 monitor_pid = pid;
2199 sigsetmask(omask);
2200
2201 switch (pid) {
2202 case -1:
2203 error("cannot fork");
2204 break;
2205 case 0:
2206 break;
2207 default:
2208 return (0);
2209 }
2210
2211 if (chdir("/") == -1)
2212 error("chdir(\"/\")");
2213
2214 setproctitle("%s [priv]", ifi->name);
2215
2216 dup2(nullfd, STDIN_FILENO);
2217 dup2(nullfd, STDOUT_FILENO);
2218 dup2(nullfd, STDERR_FILENO);
2219 close(nullfd);
2220 close(fd2);
2221
2222 for (;;) {
2223 pfd[0].fd = fd;
2224 pfd[0].events = POLLIN;
2225 if ((nfds = poll(pfd, 1, INFTIM)) == -1)
2226 if (errno != EINTR)
2227 error("poll error");
2228
2229 /*
2230 * Handle temporary errors, but bail if they persist.
2231 */
2232 if (nfds == 0 || !(pfd[0].revents & POLLIN)) {
2233 if (pfail > POLL_FAILURES)
2234 error("poll failed > %d times", POLL_FAILURES);
2235 sleep(pfail * POLL_FAILURE_WAIT);
2236 pfail++;
2237 continue;
2238 }
2239
2240 dispatch_imsg(fd);
2241 }
2242 }
2243
2244 void
2245 get_ifname(char *ifname, char *arg)
2246 {
2247 struct ifgroupreq ifgr;
2248 struct ifg_req *ifg;
2249 int s, len;
2250
2251 if (!strcmp(arg, "egress")) {
2252 s = socket(AF_INET, SOCK_DGRAM, 0);
2253 if (s == -1)
2254 error("socket error");
2255 bzero(&ifgr, sizeof(ifgr));
2256 strlcpy(ifgr.ifgr_name, "egress", sizeof(ifgr.ifgr_name));
2257 if (ioctl(s, SIOCGIFGMEMB, (caddr_t)&ifgr) == -1) {
2258 if (errno == ENOENT)
2259 error("no interface in group egress found");
2260 error("ioctl SIOCGIFGMEMB: %m");
2261 }
2262 len = ifgr.ifgr_len;
2263 if ((ifgr.ifgr_groups = calloc(1, len)) == NULL)
2264 error("get_ifname");
2265 if (ioctl(s, SIOCGIFGMEMB, (caddr_t)&ifgr) == -1)
2266 error("ioctl SIOCGIFGMEMB: %m");
2267
2268 arg = NULL;
2269 for (ifg = ifgr.ifgr_groups;
2270 ifg && len >= sizeof(struct ifg_req); ifg++) {
2271 len -= sizeof(struct ifg_req);
2272 if (arg)
2273 error("too many interfaces in group egress");
2274 arg = ifg->ifgrq_member;
2275 }
2276
2277 if (strlcpy(ifi->name, arg, IFNAMSIZ) >= IFNAMSIZ)
2278 error("Interface name too long: %m");
2279
2280 free(ifgr.ifgr_groups);
2281 close(s);
2282 } else if (strlcpy(ifi->name, arg, IFNAMSIZ) >= IFNAMSIZ)
2283 error("Interface name too long");
2284 }
2285
2286 static
2287 void
2288 sig_handle(int signo)
2289 {
2290 if (monitor_pid > 0)
2291 kill(monitor_pid, signo);
2292 fprintf(stderr, "killed by signal\n");
2293 exit(1);
2294 }
2295
2296 static
2297 int
2298 killclient(int fd)
2299 {
2300 int noclient = 1;
2301
2302 /*
2303 * Kill previously running dhclient
2304 */
2305 if (flock(fd, LOCK_EX|LOCK_NB) < 0) {
2306 char buf[256];
2307 ssize_t n;
2308 pid_t pid;
2309
2310 lseek(fd, 0L, SEEK_SET);
2311 n = read(fd, buf, sizeof(buf));
2312 if (n > 0) {
2313 buf[n-1] = 0;
2314 pid = strtol(buf, NULL, 10);
2315 if ((int)pid > 0) {
2316 noclient = 0;
2317 kill(pid, SIGINT);
2318 }
2319 }
2320 if (flock(fd, LOCK_EX|LOCK_NB) < 0)
2321 usleep(20000);
2322 while (flock(fd, LOCK_EX|LOCK_NB) < 0)
2323 sleep(1);
2324 }
2325 return noclient;
2326 }
DragonFly BSD