1 #include <u.h>
2 #include <libc.h>
3 #include <ip.h>
4 #include <bio.h>
5 #include <ndb.h>
6 #include "dat.h"
7
8 /*
9 * ala rfc2131
10 */
11
12 enum {
13 Maxloglen = 1024,
14 };
15
16 typedef struct Req Req;
17 struct Req
18 {
19 int fd; /* for reply */
20 Bootp *bp;
21 Udphdr *up;
22 uchar *e; /* end of received message */
23 uchar *p; /* options pointer */
24 uchar *max; /* max end of reply */
25
26 /* expanded to v6 */
27 uchar ciaddr[IPaddrlen];
28 uchar giaddr[IPaddrlen];
29
30 /* parsed options */
31 int p9request; /* flag: this is a bootp with plan9 options */
32 int genrequest; /* flag: this is a bootp with generic options */
33 int broadcast; /* flag: request was broadcast */
34 int dhcptype; /* dhcp message type */
35 int leasetime; /* dhcp lease */
36 uchar ip[IPaddrlen]; /* requested address */
37 uchar server[IPaddrlen]; /* server address */
38 char msg[ERRMAX]; /* error message */
39 char vci[32]; /* vendor class id */
40 char *id; /* client id */
41 uchar requested[32]; /* requested params */
42 uchar vendorclass[32];
43 char cputype[32-3];
44
45 Info gii; /* about target network */
46 Info ii; /* about target system */
47 int staticbinding;
48
49 uchar buf[2*1024]; /* message buffer */
50 };
51
52 #define TFTP "/lib/tftpd"
53
54 char *blog = "ipboot";
55 char mysysname[64];
56 Ipifc *ipifcs;
57 int debug;
58 int nobootp;
59 long now;
60 int slowstat, slowdyn;
61 char net[256];
62
63 int pptponly; /* only answer request that came from the pptp server */
64 int mute, mutestat;
65 int minlease = MinLease;
66 int staticlease = StaticLease;
67
68 uvlong start;
69
70 static int v6opts;
71
72 /* option magic */
73 char plan9opt[4] = { 'p', '9', ' ', ' ' };
74 char genericopt[4] = { 0x63, 0x82, 0x53, 0x63 };
75
76 /* well known addresses */
77 uchar zeros[Maxhwlen];
78
79 /* option debug buffer */
80 char optbuf[1024];
81 char *op;
82 char *oe = optbuf + sizeof(optbuf);
83
84 char *optname[256] =
85 {
86 [OBend] "end",
87 [OBpad] "pad",
88 [OBmask] "mask",
89 [OBtimeoff] "timeoff",
90 [OBrouter] "router",
91 [OBtimeserver] "time",
92 [OBnameserver] "name",
93 [OBdnserver] "dns",
94 [OBlogserver] "log",
95 [OBcookieserver] "cookie",
96 [OBlprserver] "lpr",
97 [OBimpressserver] "impress",
98 [OBrlserver] "rl",
99 [OBhostname] "host",
100 [OBbflen] "bflen",
101 [OBdumpfile] "dumpfile",
102 [OBdomainname] "dom",
103 [OBswapserver] "swap",
104 [OBrootpath] "rootpath",
105 [OBextpath] "extpath",
106 [OBipforward] "ipforward",
107 [OBnonlocal] "nonlocal",
108 [OBpolicyfilter] "policyfilter",
109 [OBmaxdatagram] "maxdatagram",
110 [OBttl] "ttl",
111 [OBpathtimeout] "pathtimeout",
112 [OBpathplateau] "pathplateau",
113 [OBmtu] "mtu",
114 [OBsubnetslocal] "subnetslocal",
115 [OBbaddr] "baddr",
116 [OBdiscovermask] "discovermask",
117 [OBsupplymask] "supplymask",
118 [OBdiscoverrouter] "discoverrouter",
119 [OBrsserver] "rsserver",
120 [OBstaticroutes] "staticroutes",
121 [OBtrailerencap] "trailerencap",
122 [OBarptimeout] "arptimeout",
123 [OBetherencap] "etherencap",
124 [OBtcpttl] "tcpttl",
125 [OBtcpka] "tcpka",
126 [OBtcpkag] "tcpkag",
127 [OBnisdomain] "nisdomain",
128 [OBniserver] "niserver",
129 [OBntpserver] "ntpserver",
130 [OBvendorinfo] "vendorinfo",
131 [OBnetbiosns] "NBns",
132 [OBnetbiosdds] "NBdds",
133 [OBnetbiostype] "NBtype",
134 [OBnetbiosscope] "NBscope",
135 [OBxfontserver] "xfont",
136 [OBxdispmanager] "xdisp",
137 [OBnisplusdomain] "NPdomain",
138 [OBnisplusserver] "NP",
139 [OBhomeagent] "homeagent",
140 [OBsmtpserver] "smtp",
141 [OBpop3server] "pop3",
142 [OBnntpserver] "nntp",
143 [OBwwwserver] "www",
144 [OBfingerserver] "finger",
145 [OBircserver] "ircserver",
146 [OBstserver] "stserver",
147 [OBstdaserver] "stdaserver",
148
149 /* dhcp options */
150 [ODipaddr] "ip",
151 [ODlease] "leas",
152 [ODoverload] "overload",
153 [ODtype] "typ",
154 [ODserverid] "sid",
155 [ODparams] "params",
156 [ODmessage] "message",
157 [ODmaxmsg] "maxmsg",
158 [ODrenewaltime] "renewaltime",
159 [ODrebindingtime] "rebindingtime",
160 [ODvendorclass] "vendorclass",
161 [ODclientid] "cid",
162 [ODtftpserver] "tftpserver",
163 [ODbootfile] "bf",
164 };
165
166 void addropt(Req*, int, uchar*);
167 void addrsopt(Req*, int, uchar**, int);
168 void arpenter(uchar*, uchar*);
169 void bootp(Req*);
170 void byteopt(Req*, int, uchar);
171 void dhcp(Req*);
172 void fatal(int, char*, ...);
173 void hexopt(Req*, int, char*);
174 void logdhcp(Req*);
175 void logdhcpout(Req *, char *);
176 void longopt(Req*, int, long);
177 void maskopt(Req*, int, uchar*);
178 void miscoptions(Req*, uchar*);
179 int openlisten(char *net);
180 void p9addrsopt(Req *rp, int t, uchar **ip, int i);
181 void parseoptions(Req*);
182 void proto(Req*, int);
183 void rcvdecline(Req*);
184 void rcvdiscover(Req*);
185 void rcvinform(Req*);
186 void rcvrelease(Req*);
187 void rcvrequest(Req*);
188 int readlast(int, uchar*, int);
189 char* readsysname(void);
190 void remrequested(Req*, int);
191 void sendack(Req*, uchar*, int, int);
192 void sendnak(Req*, char*);
193 void sendoffer(Req*, uchar*, int);
194 void stringopt(Req*, int, char*);
195 void termopt(Req*);
196 int validip(uchar*);
197 void vectoropt(Req*, int, uchar*, int);
198 void warning(int, char*, ...);
199
200 void
timestamp(char * tag)201 timestamp(char *tag)
202 {
203 uvlong t;
204
205 t = nsec()/1000;
206 syslog(0, blog, "%s %lludµs", tag, t - start);
207 }
208
209 void
usage(void)210 usage(void)
211 {
212 fprint(2, "usage: dhcp [-dmnprsSZ] [-f directory] [-M minlease] "
213 "[-x netmtpt] [-Z staticlease] addr n [addr n] ...\n");
214 exits("usage");
215 }
216
217 void
main(int argc,char ** argv)218 main(int argc, char **argv)
219 {
220 int i, n, fd;
221 uchar ip[IPaddrlen];
222 Req r;
223
224 setnetmtpt(net, sizeof net, nil);
225
226 fmtinstall('E', eipfmt);
227 fmtinstall('I', eipfmt);
228 fmtinstall('V', eipfmt);
229 fmtinstall('M', eipfmt);
230 ARGBEGIN {
231 case '6':
232 v6opts = 1;
233 break;
234 case 'd':
235 debug = 1;
236 break;
237 case 'f':
238 ndbfile = EARGF(usage());
239 break;
240 case 'm':
241 mute = 1;
242 break;
243 case 'M':
244 minlease = atoi(EARGF(usage()));
245 if(minlease <= 0)
246 minlease = MinLease;
247 break;
248 case 'n':
249 nobootp = 1;
250 break;
251 case 'p':
252 pptponly = 1;
253 break;
254 case 'r':
255 mutestat = 1;
256 break;
257 case 's':
258 slowstat = 1;
259 break;
260 case 'S':
261 slowdyn = 1;
262 break;
263 case 'x':
264 setnetmtpt(net, sizeof net, EARGF(usage()));
265 break;
266 case 'Z':
267 staticlease = atoi(EARGF(usage()));
268 if(staticlease <= 0)
269 staticlease = StaticLease;
270 break;
271 default:
272 usage();
273 break;
274 } ARGEND;
275
276 while(argc > 1){
277 parseip(ip, argv[0]);
278 if(!validip(ip))
279 usage();
280 n = atoi(argv[1]);
281 if(n <= 0)
282 usage();
283 initbinding(ip, n);
284 argc -= 2;
285 argv += 2;
286 }
287
288 /* for debugging */
289 for(i = 0; i < 256; i++)
290 if(optname[i] == 0)
291 optname[i] = smprint("%d", i);
292
293 /* what is my name? */
294 strcpy(mysysname, readsysname());
295
296 /* put process in background */
297 if(!debug)
298 switch(rfork(RFNOTEG|RFPROC|RFFDG)) {
299 case -1:
300 fatal(1, "fork");
301 case 0:
302 break;
303 default:
304 exits(0);
305 }
306
307 if (chdir(TFTP) < 0)
308 warning(1, "can't change directory to %s", TFTP);
309 fd = openlisten(net);
310
311 for(;;){
312 memset(&r, 0, sizeof(r));
313 r.fd = fd;
314 n = readlast(r.fd, r.buf, sizeof(r.buf));
315 if(n < Udphdrsize)
316 fatal(1, "error reading requests");
317 start = nsec()/1000;
318 op = optbuf;
319 *op = 0;
320 proto(&r, n);
321 if(r.id != nil)
322 free(r.id);
323 }
324 }
325
326 void
proto(Req * rp,int n)327 proto(Req *rp, int n)
328 {
329 uchar relip[IPaddrlen];
330 char buf[64];
331
332 now = time(0);
333
334 rp->e = rp->buf + n;
335 rp->bp = (Bootp*)rp->buf;
336 rp->up = (Udphdr*)rp->buf;
337 if (ipcmp(rp->up->laddr, IPv4bcast) == 0){
338 ipmove(rp->up->laddr, rp->up->ifcaddr);
339 rp->broadcast = 1;
340 }
341 rp->max = rp->buf + Udphdrsize + MINSUPPORTED - IPUDPHDRSIZE;
342 rp->p = rp->bp->optdata;
343 v4tov6(rp->giaddr, rp->bp->giaddr);
344 v4tov6(rp->ciaddr, rp->bp->ciaddr);
345
346 if(pptponly && rp->bp->htype != 0)
347 return;
348
349 ipifcs = readipifc(net, ipifcs, -1);
350 if(validip(rp->giaddr))
351 ipmove(relip, rp->giaddr);
352 else if(validip(rp->up->raddr))
353 ipmove(relip, rp->up->raddr);
354 else
355 ipmove(relip, rp->up->laddr);
356 if(rp->e < (uchar*)rp->bp->sname){
357 warning(0, "packet too short");
358 return;
359 }
360 if(rp->bp->op != Bootrequest){
361 warning(0, "not bootrequest");
362 return;
363 }
364
365 if(rp->e >= rp->bp->optdata){
366 if(memcmp(rp->bp->optmagic, plan9opt, sizeof(rp->bp->optmagic)) == 0)
367 rp->p9request = 1;
368 if(memcmp(rp->bp->optmagic, genericopt, sizeof(rp->bp->optmagic)) == 0) {
369 rp->genrequest = 1;
370 parseoptions(rp);
371 }
372 }
373 rp->p = rp->bp->optdata;
374
375 /* If no id is specified, make one from the hardware address
376 * of the target. We assume all zeros is not a hardware address
377 * which could be a mistake.
378 */
379 if(rp->id == nil){
380 if(rp->bp->hlen > Maxhwlen){
381 warning(0, "hlen %d", rp->bp->hlen);
382 return;
383 }
384 if(memcmp(zeros, rp->bp->chaddr, rp->bp->hlen) == 0){
385 warning(0, "no chaddr");
386 return;
387 }
388 sprint(buf, "hwa%2.2ux_", rp->bp->htype);
389 rp->id = tohex(buf, rp->bp->chaddr, rp->bp->hlen);
390 }
391
392 /* info about gateway */
393 if(lookupip(relip, &rp->gii, 1) < 0){
394 warning(0, "lookupip failed");
395 return;
396 }
397
398 /* info about target system */
399 if(lookup(rp->bp, &rp->ii, &rp->gii) == 0)
400 if(rp->ii.indb && rp->ii.dhcpgroup[0] == 0)
401 rp->staticbinding = 1;
402
403 if(rp->dhcptype)
404 dhcp(rp);
405 else
406 bootp(rp);
407 timestamp("done");
408 }
409
410 /*
411 * since we are single-threaded, this causes us to effectively
412 * stop listening while we sleep.
413 */
414 static void
slowdelay(Req * rp)415 slowdelay(Req *rp)
416 {
417 if(slowstat && rp->staticbinding || slowdyn && !rp->staticbinding)
418 sleep(1000);
419 }
420
421 void
dhcp(Req * rp)422 dhcp(Req *rp)
423 {
424 logdhcp(rp);
425
426 switch(rp->dhcptype){
427 case Discover:
428 slowdelay(rp);
429 rcvdiscover(rp);
430 break;
431 case Request:
432 rcvrequest(rp);
433 break;
434 case Decline:
435 rcvdecline(rp);
436 break;
437 case Release:
438 rcvrelease(rp);
439 break;
440 case Inform:
441 rcvinform(rp);
442 break;
443 }
444 }
445
446 void
rcvdiscover(Req * rp)447 rcvdiscover(Req *rp)
448 {
449 Binding *b, *nb;
450
451 if(rp->staticbinding){
452 sendoffer(rp, rp->ii.ipaddr, (staticlease > minlease? staticlease: minlease));
453 return;
454 }
455
456 /*
457 * first look for an outstanding offer
458 */
459 b = idtooffer(rp->id, &rp->gii);
460
461 /*
462 * rfc2131 says:
463 * If an address is available, the new address
464 * SHOULD be chosen as follows:
465 *
466 * o The client's current address as recorded in the client's current
467 * binding, ELSE
468 *
469 * o The client's previous address as recorded in the client's (now
470 * expired or released) binding, if that address is in the server's
471 * pool of available addresses and not already allocated, ELSE
472 *
473 * o The address requested in the 'Requested IP Address' option, if that
474 * address is valid and not already allocated, ELSE
475 *
476 * o A new address allocated from the server's pool of available
477 * addresses; the address is selected based on the subnet from which
478 * the message was received (if 'giaddr' is 0) or on the address of
479 * the relay agent that forwarded the message ('giaddr' when not 0).
480 */
481 if(b == nil){
482 b = idtobinding(rp->id, &rp->gii, 1);
483 if(b && b->boundto && strcmp(b->boundto, rp->id) != 0)
484 if(validip(rp->ip) && samenet(rp->ip, &rp->gii)){
485 nb = iptobinding(rp->ip, 0);
486 if(nb && nb->lease < now)
487 b = nb;
488 }
489 }
490 if(b == nil){
491 warning(0, "!Discover(%s via %I): no binding %I",
492 rp->id, rp->gii.ipaddr, rp->ip);
493 return;
494 }
495 mkoffer(b, rp->id, rp->leasetime);
496 sendoffer(rp, b->ip, b->offer);
497 }
498
499 void
rcvrequest(Req * rp)500 rcvrequest(Req *rp)
501 {
502 Binding *b;
503
504 if(validip(rp->server)){
505 /* this is a reply to an offer - SELECTING */
506
507 /* check for hard assignment */
508 if(rp->staticbinding){
509 if(forme(rp->server))
510 sendack(rp, rp->ii.ipaddr,
511 (staticlease > minlease? staticlease:
512 minlease), 1);
513 else
514 warning(0, "!Request(%s via %I): for server %I not me",
515 rp->id, rp->gii.ipaddr, rp->server);
516 return;
517 }
518
519 b = idtooffer(rp->id, &rp->gii);
520
521 /* if we don't have an offer, nak */
522 if(b == nil){
523 warning(0, "!Request(%s via %I): no offer",
524 rp->id, rp->gii.ipaddr);
525 if(forme(rp->server))
526 sendnak(rp, "no offer for you");
527 return;
528 }
529
530 /* if not for me, retract offer */
531 if(!forme(rp->server)){
532 b->expoffer = 0;
533 warning(0, "!Request(%s via %I): for server %I not me",
534 rp->id, rp->gii.ipaddr, rp->server);
535 return;
536 }
537
538 /*
539 * if the client is confused about what we offered, nak.
540 * client really shouldn't be specifying this when selecting
541 */
542 if(validip(rp->ip) && ipcmp(rp->ip, b->ip) != 0){
543 warning(0, "!Request(%s via %I): requests %I, not %I",
544 rp->id, rp->gii.ipaddr, rp->ip, b->ip);
545 sendnak(rp, "bad ip address option");
546 return;
547 }
548 if(commitbinding(b) < 0){
549 warning(0, "!Request(%s via %I): can't commit %I",
550 rp->id, rp->gii.ipaddr, b->ip);
551 sendnak(rp, "can't commit binding");
552 return;
553 }
554 sendack(rp, b->ip, b->offer, 1);
555 } else if(validip(rp->ip)){
556 /*
557 * checking address/net - INIT-REBOOT
558 *
559 * This is a rebooting client that remembers its old
560 * address.
561 */
562 /* check for hard assignment */
563 if(rp->staticbinding){
564 if(memcmp(rp->ip, rp->ii.ipaddr, IPaddrlen) != 0){
565 warning(0, "!Request(%s via %I): %I not valid for %E",
566 rp->id, rp->gii.ipaddr, rp->ip, rp->bp->chaddr);
567 sendnak(rp, "not valid");
568 }
569 sendack(rp, rp->ii.ipaddr, (staticlease > minlease?
570 staticlease: minlease), 1);
571 return;
572 }
573
574 /* make sure the network makes sense */
575 if(!samenet(rp->ip, &rp->gii)){
576 warning(0, "!Request(%s via %I): bad forward of %I",
577 rp->id, rp->gii.ipaddr, rp->ip);
578 sendnak(rp, "wrong network");
579 return;
580 }
581 b = iptobinding(rp->ip, 0);
582 if(b == nil){
583 warning(0, "!Request(%s via %I): no binding for %I",
584 rp->id, rp->gii.ipaddr, rp->ip);
585 return;
586 }
587 if(memcmp(rp->ip, b->ip, IPaddrlen) != 0 || now > b->lease){
588 warning(0, "!Request(%s via %I): %I not valid",
589 rp->id, rp->gii.ipaddr, rp->ip);
590 sendnak(rp, "not valid");
591 return;
592 }
593 b->offer = b->lease - now;
594 sendack(rp, b->ip, b->offer, 1);
595 } else if(validip(rp->ciaddr)){
596 /*
597 * checking address - RENEWING or REBINDING
598 *
599 * these states are indistinguishable in our action. The only
600 * difference is how close to lease expiration the client is.
601 * If it is really close, it broadcasts the request hoping that
602 * some server will answer.
603 */
604
605 /* check for hard assignment */
606 if(rp->staticbinding){
607 if(ipcmp(rp->ciaddr, rp->ii.ipaddr) != 0){
608 warning(0, "!Request(%s via %I): %I not valid",
609 rp->id, rp->gii.ipaddr, rp->ciaddr);
610 sendnak(rp, "not valid");
611 }
612 sendack(rp, rp->ii.ipaddr, (staticlease > minlease?
613 staticlease: minlease), 1);
614 return;
615 }
616
617 /* make sure the network makes sense */
618 if(!samenet(rp->ciaddr, &rp->gii)){
619 warning(0, "!Request(%s via %I): bad forward of %I",
620 rp->id, rp->gii.ipaddr, rp->ip);
621 sendnak(rp, "wrong network");
622 return;
623 }
624 b = iptobinding(rp->ciaddr, 0);
625 if(b == nil){
626 warning(0, "!Request(%s via %I): no binding for %I",
627 rp->id, rp->gii.ipaddr, rp->ciaddr);
628 return;
629 }
630 if(ipcmp(rp->ciaddr, b->ip) != 0){
631 warning(0, "!Request(%I via %s): %I not valid",
632 rp->id, rp->gii.ipaddr, rp->ciaddr);
633 sendnak(rp, "invalid ip address");
634 return;
635 }
636 mkoffer(b, rp->id, rp->leasetime);
637 if(commitbinding(b) < 0){
638 warning(0, "!Request(%s via %I): can't commit %I",
639 rp->id, rp->gii.ipaddr, b->ip);
640 sendnak(rp, "can't commit binding");
641 return;
642 }
643 sendack(rp, b->ip, b->offer, 1);
644 }
645 }
646
647 void
rcvdecline(Req * rp)648 rcvdecline(Req *rp)
649 {
650 Binding *b;
651 char buf[64];
652
653 if(rp->staticbinding)
654 return;
655
656 b = idtooffer(rp->id, &rp->gii);
657 if(b == nil){
658 warning(0, "!Decline(%s via %I): no binding",
659 rp->id, rp->gii.ipaddr);
660 return;
661 }
662
663 /* mark ip address as in use */
664 snprint(buf, sizeof(buf), "declined by %s", rp->id);
665 mkoffer(b, buf, 0x7fffffff);
666 commitbinding(b);
667 }
668
669 void
rcvrelease(Req * rp)670 rcvrelease(Req *rp)
671 {
672 Binding *b;
673
674 if(rp->staticbinding)
675 return;
676
677 b = idtobinding(rp->id, &rp->gii, 0);
678 if(b == nil){
679 warning(0, "!Release(%s via %I): no binding",
680 rp->id, rp->gii.ipaddr);
681 return;
682 }
683 if(strcmp(rp->id, b->boundto) != 0){
684 warning(0, "!Release(%s via %I): invalid release of %I",
685 rp->id, rp->gii.ipaddr, rp->ip);
686 return;
687 }
688 warning(0, "Release(%s via %I): releasing %I", b->boundto, rp->gii.ipaddr, b->ip);
689 if(releasebinding(b, rp->id) < 0)
690 warning(0, "release: couldn't release");
691 }
692
693 void
rcvinform(Req * rp)694 rcvinform(Req *rp)
695 {
696 Binding *b;
697
698 if(rp->staticbinding){
699 sendack(rp, rp->ii.ipaddr, 0, 0);
700 return;
701 }
702
703 b = iptobinding(rp->ciaddr, 0);
704 if(b == nil){
705 warning(0, "!Inform(%s via %I): no binding for %I",
706 rp->id, rp->gii.ipaddr, rp->ip);
707 return;
708 }
709 sendack(rp, b->ip, 0, 0);
710 }
711
712 int
setsiaddr(uchar * siaddr,uchar * saddr,uchar * laddr)713 setsiaddr(uchar *siaddr, uchar *saddr, uchar *laddr)
714 {
715 if(ipcmp(saddr, IPnoaddr) != 0){
716 v6tov4(siaddr, saddr);
717 return 0;
718 } else {
719 v6tov4(siaddr, laddr);
720 return 1;
721 }
722 }
723
724 int
ismuted(Req * rp)725 ismuted(Req *rp)
726 {
727 return mute || (mutestat && rp->staticbinding);
728 }
729
730 void
sendoffer(Req * rp,uchar * ip,int offer)731 sendoffer(Req *rp, uchar *ip, int offer)
732 {
733 int n;
734 ushort flags;
735 Bootp *bp;
736 Udphdr *up;
737
738 bp = rp->bp;
739 up = rp->up;
740
741 /*
742 * set destination
743 */
744 flags = nhgets(bp->flags);
745 if(validip(rp->giaddr)){
746 ipmove(up->raddr, rp->giaddr);
747 hnputs(up->rport, 67);
748 } else if(flags & Fbroadcast){
749 ipmove(up->raddr, IPv4bcast);
750 hnputs(up->rport, 68);
751 } else {
752 ipmove(up->raddr, ip);
753 if(bp->htype == 1)
754 arpenter(up->raddr, bp->chaddr);
755 hnputs(up->rport, 68);
756 }
757
758 /*
759 * fill in standard bootp part
760 */
761 bp->op = Bootreply;
762 bp->hops = 0;
763 hnputs(bp->secs, 0);
764 memset(bp->ciaddr, 0, sizeof(bp->ciaddr));
765 v6tov4(bp->giaddr, rp->giaddr);
766 v6tov4(bp->yiaddr, ip);
767 setsiaddr(bp->siaddr, rp->ii.tftp, up->laddr);
768 strncpy(bp->sname, mysysname, sizeof(bp->sname));
769 strncpy(bp->file, rp->ii.bootf, sizeof(bp->file));
770
771 /*
772 * set options
773 */
774 byteopt(rp, ODtype, Offer);
775 longopt(rp, ODlease, offer);
776 addropt(rp, ODserverid, up->laddr);
777 miscoptions(rp, ip);
778 termopt(rp);
779
780 logdhcpout(rp, "Offer");
781
782 /*
783 * send
784 */
785 n = rp->p - rp->buf;
786 if(!ismuted(rp) && write(rp->fd, rp->buf, n) != n)
787 warning(0, "offer: write failed: %r");
788 }
789
790 void
sendack(Req * rp,uchar * ip,int offer,int sendlease)791 sendack(Req *rp, uchar *ip, int offer, int sendlease)
792 {
793 int n;
794 ushort flags;
795 Bootp *bp;
796 Udphdr *up;
797
798 bp = rp->bp;
799 up = rp->up;
800
801 /*
802 * set destination
803 */
804 flags = nhgets(bp->flags);
805 if(validip(rp->giaddr)){
806 ipmove(up->raddr, rp->giaddr);
807 hnputs(up->rport, 67);
808 } else if(flags & Fbroadcast){
809 ipmove(up->raddr, IPv4bcast);
810 hnputs(up->rport, 68);
811 } else {
812 ipmove(up->raddr, ip);
813 if(bp->htype == 1)
814 arpenter(up->raddr, bp->chaddr);
815 hnputs(up->rport, 68);
816 }
817
818 /*
819 * fill in standard bootp part
820 */
821 bp->op = Bootreply;
822 bp->hops = 0;
823 hnputs(bp->secs, 0);
824 v6tov4(bp->giaddr, rp->giaddr);
825 v6tov4(bp->yiaddr, ip);
826 setsiaddr(bp->siaddr, rp->ii.tftp, up->laddr);
827 strncpy(bp->sname, mysysname, sizeof(bp->sname));
828 strncpy(bp->file, rp->ii.bootf, sizeof(bp->file));
829
830 /*
831 * set options
832 */
833 byteopt(rp, ODtype, Ack);
834 if(sendlease){
835 longopt(rp, ODlease, offer);
836 }
837 addropt(rp, ODserverid, up->laddr);
838 miscoptions(rp, ip);
839 termopt(rp);
840
841 logdhcpout(rp, "Ack");
842
843 /*
844 * send
845 */
846 n = rp->p - rp->buf;
847 if(!ismuted(rp) && write(rp->fd, rp->buf, n) != n)
848 warning(0, "ack: write failed: %r");
849 }
850
851 void
sendnak(Req * rp,char * msg)852 sendnak(Req *rp, char *msg)
853 {
854 int n;
855 Bootp *bp;
856 Udphdr *up;
857
858 bp = rp->bp;
859 up = rp->up;
860
861 /*
862 * set destination (always broadcast)
863 */
864 if(validip(rp->giaddr)){
865 ipmove(up->raddr, rp->giaddr);
866 hnputs(up->rport, 67);
867 } else {
868 ipmove(up->raddr, IPv4bcast);
869 hnputs(up->rport, 68);
870 }
871
872 /*
873 * fill in standard bootp part
874 */
875 bp->op = Bootreply;
876 bp->hops = 0;
877 hnputs(bp->secs, 0);
878 v6tov4(bp->giaddr, rp->giaddr);
879 memset(bp->ciaddr, 0, sizeof(bp->ciaddr));
880 memset(bp->yiaddr, 0, sizeof(bp->yiaddr));
881 memset(bp->siaddr, 0, sizeof(bp->siaddr));
882
883 /*
884 * set options
885 */
886 byteopt(rp, ODtype, Nak);
887 addropt(rp, ODserverid, up->laddr);
888 if(msg)
889 stringopt(rp, ODmessage, msg);
890 if(strncmp(rp->id, "id", 2) == 0)
891 hexopt(rp, ODclientid, rp->id+2);
892 termopt(rp);
893
894 logdhcpout(rp, "Nak");
895
896 /*
897 * send nak
898 */
899 n = rp->p - rp->buf;
900 if(!ismuted(rp) && write(rp->fd, rp->buf, n) != n)
901 warning(0, "nak: write failed: %r");
902 }
903
904 void
bootp(Req * rp)905 bootp(Req *rp)
906 {
907 int n;
908 Bootp *bp;
909 Udphdr *up;
910 ushort flags;
911 Iplifc *lifc;
912 Info *iip;
913
914 warning(0, "bootp %s %I->%I from %s via %I, file %s %s",
915 rp->genrequest? "generic": (rp->p9request? "p9": ""),
916 rp->up->raddr, rp->up->laddr,
917 rp->id, rp->gii.ipaddr,
918 rp->bp->file, rp->broadcast? "broadcast": "unicast");
919
920 if(nobootp)
921 return;
922
923 bp = rp->bp;
924 up = rp->up;
925 iip = &rp->ii;
926
927 if(rp->staticbinding == 0){
928 warning(0, "bootp from unknown %s via %I", rp->id, rp->gii.ipaddr);
929 return;
930 }
931
932 /* ignore if not for us */
933 if(*bp->sname){
934 if(strcmp(bp->sname, mysysname) != 0){
935 bp->sname[20] = 0;
936 warning(0, "bootp for server %s", bp->sname);
937 return;
938 }
939 } else
940 slowdelay(rp);
941
942 /* ignore if we don't know what file to load */
943 if(*bp->file == 0){
944 if(rp->genrequest && *iip->bootf2) /* if not plan 9 & have alternate file... */
945 strncpy(bp->file, iip->bootf2, sizeof(bp->file));
946 else if(*iip->bootf)
947 strncpy(bp->file, iip->bootf, sizeof(bp->file));
948 else if(*bp->sname) /* if we were asked, respond no matter what */
949 bp->file[0] = '\0';
950 else {
951 warning(0, "no bootfile for %I", iip->ipaddr);
952 return;
953 }
954 }
955
956 /* ignore if the file is unreadable */
957 if((!rp->genrequest) && bp->file[0] && access(bp->file, 4) < 0){
958 warning(0, "inaccessible bootfile1 %s", bp->file);
959 return;
960 }
961
962 bp->op = Bootreply;
963 v6tov4(bp->yiaddr, iip->ipaddr);
964 if(rp->p9request){
965 warning(0, "p9bootp: %I", iip->ipaddr);
966 memmove(bp->optmagic, plan9opt, 4);
967 if(iip->gwip == 0)
968 v4tov6(iip->gwip, bp->giaddr);
969 rp->p += sprint((char*)rp->p, "%V %I %I %I", iip->ipmask+IPv4off, iip->fsip,
970 iip->auip, iip->gwip);
971 sprint(optbuf, "%s", (char*)(bp->optmagic));
972 } else if(rp->genrequest){
973 warning(0, "genericbootp: %I", iip->ipaddr);
974 memmove(bp->optmagic, genericopt, 4);
975 miscoptions(rp, iip->ipaddr);
976 termopt(rp);
977 } else if(iip->vendor[0] != 0) {
978 warning(0, "bootp vendor field: %s", iip->vendor);
979 memset(rp->p, 0, 128-4);
980 rp->p += sprint((char*)bp->optmagic, "%s", iip->vendor);
981 } else {
982 memset(rp->p, 0, 128-4);
983 rp->p += 128-4;
984 }
985
986 /*
987 * set destination
988 */
989 flags = nhgets(bp->flags);
990 if(validip(rp->giaddr)){
991 ipmove(up->raddr, rp->giaddr);
992 hnputs(up->rport, 67);
993 } else if(flags & Fbroadcast){
994 ipmove(up->raddr, IPv4bcast);
995 hnputs(up->rport, 68);
996 } else {
997 v4tov6(up->raddr, bp->yiaddr);
998 if(bp->htype == 1)
999 arpenter(up->raddr, bp->chaddr);
1000 hnputs(up->rport, 68);
1001 }
1002
1003 /*
1004 * select best local address if destination is directly connected
1005 */
1006 lifc = findlifc(up->raddr);
1007 if(lifc)
1008 ipmove(up->laddr, lifc->ip);
1009
1010 /*
1011 * our identity
1012 */
1013 strncpy(bp->sname, mysysname, sizeof(bp->sname));
1014
1015 /*
1016 * set tftp server
1017 */
1018 setsiaddr(bp->siaddr, iip->tftp, up->laddr);
1019 if(rp->genrequest && *iip->bootf2)
1020 setsiaddr(bp->siaddr, iip->tftp2, up->laddr);
1021
1022 /*
1023 * RFC 1048 says that we must pad vendor field with
1024 * zeros until we have a 64 byte field.
1025 */
1026 n = rp->p - rp->bp->optdata;
1027 if(n < 64-4) {
1028 memset(rp->p, 0, (64-4)-n);
1029 rp->p += (64-4)-n;
1030 }
1031
1032 /*
1033 * send
1034 */
1035 n = rp->p - rp->buf;
1036 if(!ismuted(rp) && write(rp->fd, rp->buf, n) != n)
1037 warning(0, "bootp: write failed: %r");
1038
1039 warning(0, "bootp via %I: file %s xid(%ux)flag(%ux)ci(%V)gi(%V)yi(%V)si(%V) %s",
1040 up->raddr, bp->file, nhgetl(bp->xid), nhgets(bp->flags),
1041 bp->ciaddr, bp->giaddr, bp->yiaddr, bp->siaddr,
1042 optbuf);
1043 }
1044
1045 void
parseoptions(Req * rp)1046 parseoptions(Req *rp)
1047 {
1048 int n, c, code;
1049 uchar *o, *p;
1050
1051 p = rp->p;
1052
1053 while(p < rp->e){
1054 code = *p++;
1055 if(code == 255)
1056 break;
1057 if(code == 0)
1058 continue;
1059
1060 /* ignore anything that's too long */
1061 n = *p++;
1062 o = p;
1063 p += n;
1064 if(p > rp->e)
1065 return;
1066
1067 switch(code){
1068 case ODipaddr: /* requested ip address */
1069 if(n == IPv4addrlen)
1070 v4tov6(rp->ip, o);
1071 break;
1072 case ODlease: /* requested lease time */
1073 rp->leasetime = nhgetl(o);
1074 if(rp->leasetime > MaxLease || rp->leasetime < 0)
1075 rp->leasetime = MaxLease;
1076 break;
1077 case ODtype:
1078 c = *o;
1079 if(c < 10 && c > 0)
1080 rp->dhcptype = c;
1081 break;
1082 case ODserverid:
1083 if(n == IPv4addrlen)
1084 v4tov6(rp->server, o);
1085 break;
1086 case ODmessage:
1087 if(n > sizeof rp->msg-1)
1088 n = sizeof rp->msg-1;
1089 memmove(rp->msg, o, n);
1090 rp->msg[n] = 0;
1091 break;
1092 case ODmaxmsg:
1093 c = nhgets(o);
1094 c -= 28;
1095 c += Udphdrsize;
1096 if(c > 0)
1097 rp->max = rp->buf + c;
1098 break;
1099 case ODclientid:
1100 if(n <= 1)
1101 break;
1102 rp->id = toid( o, n);
1103 break;
1104 case ODparams:
1105 if(n > sizeof(rp->requested))
1106 n = sizeof(rp->requested);
1107 memmove(rp->requested, o, n);
1108 break;
1109 case ODvendorclass:
1110 if(n >= sizeof(rp->vendorclass))
1111 n = sizeof(rp->vendorclass)-1;
1112 memmove(rp->vendorclass, o, n);
1113 rp->vendorclass[n] = 0;
1114 if(strncmp((char*)rp->vendorclass, "p9-", 3) == 0)
1115 strcpy(rp->cputype, (char*)rp->vendorclass+3);
1116 break;
1117 case OBend:
1118 return;
1119 }
1120 }
1121 }
1122
1123 void
remrequested(Req * rp,int opt)1124 remrequested(Req *rp, int opt)
1125 {
1126 uchar *p;
1127
1128 p = memchr(rp->requested, opt, sizeof(rp->requested));
1129 if(p != nil)
1130 *p = OBpad;
1131 }
1132
1133 void
miscoptions(Req * rp,uchar * ip)1134 miscoptions(Req *rp, uchar *ip)
1135 {
1136 int i, j, na;
1137 uchar x[2*IPaddrlen], vopts[Maxoptlen];
1138 uchar *op, *omax;
1139 uchar *addrs[2];
1140 char *p;
1141 char *attr[100], **a;
1142 Ndbtuple *t;
1143
1144 addrs[0] = x;
1145 addrs[1] = x+IPaddrlen;
1146
1147 /* always supply these */
1148 maskopt(rp, OBmask, rp->gii.ipmask);
1149 if(validip(rp->gii.gwip)){
1150 remrequested(rp, OBrouter);
1151 addropt(rp, OBrouter, rp->gii.gwip);
1152 } else if(validip(rp->giaddr)){
1153 remrequested(rp, OBrouter);
1154 addropt(rp, OBrouter, rp->giaddr);
1155 }
1156
1157 /*
1158 * OBhostname for the HP4000M switches
1159 * (this causes NT to log infinite errors - tough shit)
1160 */
1161 if(*rp->ii.domain){
1162 remrequested(rp, OBhostname);
1163 stringopt(rp, OBhostname, rp->ii.domain);
1164 }
1165 if(*rp->ii.rootpath)
1166 stringopt(rp, OBrootpath, rp->ii.rootpath);
1167
1168 /* figure out what we need to lookup */
1169 na = 0;
1170 a = attr;
1171 if(*rp->ii.domain == 0)
1172 a[na++] = "dom";
1173 for(i = 0; i < sizeof(rp->requested); i++)
1174 switch(rp->requested[i]){
1175 case OBrouter:
1176 a[na++] = "@ipgw";
1177 break;
1178 case OBdnserver:
1179 a[na++] = "@dns";
1180 break;
1181 case OBnetbiosns:
1182 a[na++] = "@wins";
1183 break;
1184 case OBsmtpserver:
1185 a[na++] = "@smtp";
1186 break;
1187 case OBpop3server:
1188 a[na++] = "@pop3";
1189 break;
1190 case OBwwwserver:
1191 a[na++] = "@www";
1192 break;
1193 case OBntpserver:
1194 a[na++] = "@ntp";
1195 break;
1196 case OBtimeserver:
1197 a[na++] = "@time";
1198 break;
1199 }
1200 if(strncmp((char*)rp->vendorclass, "plan9_", 6) == 0
1201 || strncmp((char*)rp->vendorclass, "p9-", 3) == 0){
1202 a[na++] = "@fs";
1203 a[na++] = "@auth";
1204 }
1205 t = lookupinfo(ip, a, na);
1206
1207 /* lookup anything we might be missing */
1208 if(*rp->ii.domain == 0)
1209 lookupname(rp->ii.domain, t);
1210
1211 /* add any requested ones that we know about */
1212 for(i = 0; i < sizeof(rp->requested); i++)
1213 switch(rp->requested[i]){
1214 case OBrouter:
1215 j = lookupserver("ipgw", addrs, t);
1216 addrsopt(rp, OBrouter, addrs, j);
1217 break;
1218 case OBdnserver:
1219 j = lookupserver("dns", addrs, t);
1220 addrsopt(rp, OBdnserver, addrs, j);
1221 break;
1222 case OBhostname:
1223 if(*rp->ii.domain)
1224 stringopt(rp, OBhostname, rp->ii.domain);
1225 break;
1226 case OBdomainname:
1227 p = strchr(rp->ii.domain, '.');
1228 if(p)
1229 stringopt(rp, OBdomainname, p+1);
1230 break;
1231 case OBnetbiosns:
1232 j = lookupserver("wins", addrs, t);
1233 addrsopt(rp, OBnetbiosns, addrs, j);
1234 break;
1235 case OBnetbiostype:
1236 /* p-node: peer to peer WINS queries */
1237 byteopt(rp, OBnetbiostype, 0x2);
1238 break;
1239 case OBsmtpserver:
1240 j = lookupserver("smtp", addrs, t);
1241 addrsopt(rp, OBsmtpserver, addrs, j);
1242 break;
1243 case OBpop3server:
1244 j = lookupserver("pop3", addrs, t);
1245 addrsopt(rp, OBpop3server, addrs, j);
1246 break;
1247 case OBwwwserver:
1248 j = lookupserver("www", addrs, t);
1249 addrsopt(rp, OBwwwserver, addrs, j);
1250 break;
1251 case OBntpserver:
1252 j = lookupserver("ntp", addrs, t);
1253 addrsopt(rp, OBntpserver, addrs, j);
1254 break;
1255 case OBtimeserver:
1256 j = lookupserver("time", addrs, t);
1257 addrsopt(rp, OBtimeserver, addrs, j);
1258 break;
1259 case OBttl:
1260 byteopt(rp, OBttl, 255);
1261 break;
1262 }
1263
1264 /* add plan9 specific options */
1265 if(strncmp((char*)rp->vendorclass, "plan9_", 6) == 0
1266 || strncmp((char*)rp->vendorclass, "p9-", 3) == 0){
1267 /* point to temporary area */
1268 op = rp->p;
1269 omax = rp->max;
1270 /* stash encoded options in vopts */
1271 rp->p = vopts;
1272 rp->max = vopts + sizeof(vopts) - 1;
1273
1274 /* emit old v4 addresses first to make sure that they fit */
1275 addrsopt(rp, OP9fsv4, addrs, lookupserver("fs", addrs, t));
1276 addrsopt(rp, OP9authv4, addrs, lookupserver("auth", addrs, t));
1277
1278 p9addrsopt(rp, OP9fs, addrs, lookupserver("fs", addrs, t));
1279 p9addrsopt(rp, OP9auth, addrs, lookupserver("auth", addrs, t));
1280 p9addrsopt(rp, OP9ipaddr, addrs, lookupserver("ip", addrs, t));
1281 p9addrsopt(rp, OP9ipmask, addrs, lookupserver("ipmask", addrs, t));
1282 p9addrsopt(rp, OP9ipgw, addrs, lookupserver("ipgw", addrs, t));
1283
1284 /* point back to packet, encapsulate vopts into packet */
1285 j = rp->p - vopts;
1286 rp->p = op;
1287 rp->max = omax;
1288 vectoropt(rp, OBvendorinfo, vopts, j);
1289 }
1290
1291 ndbfree(t);
1292 }
1293
1294 int
openlisten(char * net)1295 openlisten(char *net)
1296 {
1297 int fd, cfd;
1298 char data[128], devdir[40];
1299
1300 sprint(data, "%s/udp!*!bootp", net);
1301 cfd = announce(data, devdir);
1302 if(cfd < 0)
1303 fatal(1, "can't announce");
1304 if(fprint(cfd, "headers") < 0)
1305 fatal(1, "can't set header mode");
1306
1307 sprint(data, "%s/data", devdir);
1308 fd = open(data, ORDWR);
1309 if(fd < 0)
1310 fatal(1, "open udp data");
1311 return fd;
1312 }
1313
1314 void
fatal(int syserr,char * fmt,...)1315 fatal(int syserr, char *fmt, ...)
1316 {
1317 char buf[Maxloglen];
1318 va_list arg;
1319
1320 va_start(arg, fmt);
1321 vseprint(buf, buf+sizeof(buf), fmt, arg);
1322 va_end(arg);
1323 if(syserr)
1324 syslog(1, blog, "%s: %r", buf);
1325 else
1326 syslog(1, blog, "%s", buf);
1327 exits(buf);
1328 }
1329
1330 void
warning(int syserr,char * fmt,...)1331 warning(int syserr, char *fmt, ...)
1332 {
1333 char buf[Maxloglen];
1334 va_list arg;
1335
1336 va_start(arg, fmt);
1337 vseprint(buf, buf+sizeof(buf), fmt, arg);
1338 va_end(arg);
1339 if(syserr){
1340 syslog(0, blog, "%s: %r", buf);
1341 if(debug)
1342 fprint(2, "%s: %r\n", buf);
1343 } else {
1344 syslog(0, blog, "%s", buf);
1345 if(debug)
1346 fprint(2, "%s\n", buf);
1347 }
1348 }
1349
1350 char*
readsysname(void)1351 readsysname(void)
1352 {
1353 static char name[128];
1354 char *p;
1355 int n, fd;
1356
1357 fd = open("/dev/sysname", OREAD);
1358 if(fd >= 0){
1359 n = read(fd, name, sizeof(name)-1);
1360 close(fd);
1361 if(n > 0){
1362 name[n] = 0;
1363 return name;
1364 }
1365 }
1366 p = getenv("sysname");
1367 if(p == nil || *p == 0)
1368 return "unknown";
1369 return p;
1370 }
1371
1372 extern int
validip(uchar * ip)1373 validip(uchar *ip)
1374 {
1375 if(ipcmp(ip, IPnoaddr) == 0)
1376 return 0;
1377 if(ipcmp(ip, v4prefix) == 0)
1378 return 0;
1379 return 1;
1380 }
1381
1382 void
longopt(Req * rp,int t,long v)1383 longopt(Req *rp, int t, long v)
1384 {
1385 if(rp->p + 6 > rp->max)
1386 return;
1387 *rp->p++ = t;
1388 *rp->p++ = 4;
1389 hnputl(rp->p, v);
1390 rp->p += 4;
1391
1392 op = seprint(op, oe, "%s(%ld)", optname[t], v);
1393 }
1394
1395 void
addropt(Req * rp,int t,uchar * ip)1396 addropt(Req *rp, int t, uchar *ip)
1397 {
1398 if(rp->p + 6 > rp->max)
1399 return;
1400 if (!isv4(ip)) {
1401 if (debug)
1402 warning(0, "not a v4 %s server: %I", optname[t], ip);
1403 return;
1404 }
1405 *rp->p++ = t;
1406 *rp->p++ = 4;
1407 memmove(rp->p, ip+IPv4off, 4);
1408 rp->p += 4;
1409
1410 op = seprint(op, oe, "%s(%I)", optname[t], ip);
1411 }
1412
1413 void
maskopt(Req * rp,int t,uchar * ip)1414 maskopt(Req *rp, int t, uchar *ip)
1415 {
1416 if(rp->p + 6 > rp->max)
1417 return;
1418 *rp->p++ = t;
1419 *rp->p++ = 4;
1420 memmove(rp->p, ip+IPv4off, 4);
1421 rp->p += 4;
1422
1423 op = seprint(op, oe, "%s(%M)", optname[t], ip);
1424 }
1425
1426 void
addrsopt(Req * rp,int t,uchar ** ip,int i)1427 addrsopt(Req *rp, int t, uchar **ip, int i)
1428 {
1429 int v4s, n;
1430
1431 if(i <= 0)
1432 return;
1433 if(rp->p + 2 + 4*i > rp->max)
1434 return;
1435 v4s = 0;
1436 for(n = i; n-- > 0; )
1437 if (isv4(ip[n]))
1438 v4s++;
1439 if (v4s <= 0) {
1440 if (debug)
1441 warning(0, "no v4 %s servers", optname[t]);
1442 return;
1443 }
1444 *rp->p++ = t;
1445 *rp->p++ = 4*v4s;
1446 op = seprint(op, oe, " %s(", optname[t]);
1447 while(i-- > 0){
1448 if (!isv4(*ip)) {
1449 op = seprint(op, oe, " skipping %I ", *ip);
1450 continue;
1451 }
1452 v6tov4(rp->p, *ip);
1453 rp->p += 4;
1454 op = seprint(op, oe, "%I", *ip);
1455 ip++;
1456 if(i > 0)
1457 op = seprint(op, oe, " ");
1458 }
1459 op = seprint(op, oe, ")");
1460 }
1461
1462 void
p9addrsopt(Req * rp,int t,uchar ** ip,int i)1463 p9addrsopt(Req *rp, int t, uchar **ip, int i)
1464 {
1465 char *pkt, *payload;
1466
1467 if(i <= 0 || !v6opts)
1468 return;
1469 pkt = (char *)rp->p;
1470 *pkt++ = t; /* option */
1471 pkt++; /* fill in payload length below */
1472 payload = pkt;
1473 *pkt++ = i; /* plan 9 address count */
1474 op = seprint(op, oe, " %s(", optname[t]);
1475 while(i-- > 0){
1476 pkt = seprint(pkt, (char *)rp->max, "%I", *ip);
1477 if ((uchar *)pkt+1 >= rp->max) {
1478 op = seprint(op, oe, "<out of mem1>)");
1479 return;
1480 }
1481 pkt++; /* leave NUL as terminator */
1482 op = seprint(op, oe, "%I", *ip);
1483 ip++;
1484 if(i > 0)
1485 op = seprint(op, oe, " ");
1486 }
1487 if ((uchar *)pkt - rp->p > 0377) {
1488 op = seprint(op, oe, "<out of mem2>)");
1489 return;
1490 }
1491 op = seprint(op, oe, ")");
1492 rp->p[1] = pkt - payload; /* payload length */
1493 rp->p = (uchar *)pkt;
1494 }
1495
1496 void
byteopt(Req * rp,int t,uchar v)1497 byteopt(Req *rp, int t, uchar v)
1498 {
1499 if(rp->p + 3 > rp->max)
1500 return;
1501 *rp->p++ = t;
1502 *rp->p++ = 1;
1503 *rp->p++ = v;
1504
1505 op = seprint(op, oe, "%s(%d)", optname[t], v);
1506 }
1507
1508 void
termopt(Req * rp)1509 termopt(Req *rp)
1510 {
1511 if(rp->p + 1 > rp->max)
1512 return;
1513 *rp->p++ = OBend;
1514 }
1515
1516 void
stringopt(Req * rp,int t,char * str)1517 stringopt(Req *rp, int t, char *str)
1518 {
1519 int n;
1520
1521 n = strlen(str);
1522 if(n > 255)
1523 n = 255;
1524 if(rp->p+n+2 > rp->max)
1525 return;
1526 *rp->p++ = t;
1527 *rp->p++ = n;
1528 memmove(rp->p, str, n);
1529 rp->p += n;
1530
1531 op = seprint(op, oe, "%s(%s)", optname[t], str);
1532 }
1533
1534 void
vectoropt(Req * rp,int t,uchar * v,int n)1535 vectoropt(Req *rp, int t, uchar *v, int n)
1536 {
1537 int i;
1538
1539 if(n > 255) {
1540 n = 255;
1541 op = seprint(op, oe, "vectoropt len %d > 255 ", n);
1542 }
1543 if(rp->p+n+2 > rp->max)
1544 return;
1545 *rp->p++ = t;
1546 *rp->p++ = n;
1547 memmove(rp->p, v, n);
1548 rp->p += n;
1549
1550 op = seprint(op, oe, "%s(", optname[t]);
1551 if(n > 0)
1552 op = seprint(op, oe, "%ud", v[0]);
1553 for(i = 1; i < n; i++)
1554 op = seprint(op, oe, " %ud", v[i]);
1555 op = seprint(op, oe, ")");
1556 }
1557
1558 int
fromhex(int x)1559 fromhex(int x)
1560 {
1561 if(x >= '0' && x <= '9')
1562 return x - '0';
1563 return x - 'a';
1564 }
1565
1566 void
hexopt(Req * rp,int t,char * str)1567 hexopt(Req *rp, int t, char *str)
1568 {
1569 int n;
1570
1571 n = strlen(str);
1572 n /= 2;
1573 if(n > 255)
1574 n = 255;
1575 if(rp->p+n+2 > rp->max)
1576 return;
1577 *rp->p++ = t;
1578 *rp->p++ = n;
1579 while(n-- > 0){
1580 *rp->p++ = (fromhex(str[0])<<4)|fromhex(str[1]);
1581 str += 2;
1582 }
1583
1584 op = seprint(op, oe, "%s(%s)", optname[t], str);
1585 }
1586
1587 void
arpenter(uchar * ip,uchar * ether)1588 arpenter(uchar *ip, uchar *ether)
1589 {
1590 int f;
1591 char buf[256];
1592
1593 sprint(buf, "%s/arp", net);
1594 f = open(buf, OWRITE);
1595 if(f < 0){
1596 syslog(debug, blog, "open %s: %r", buf);
1597 return;
1598 }
1599 fprint(f, "add ether %I %E", ip, ether);
1600 close(f);
1601 }
1602
1603 char *dhcpmsgname[] =
1604 {
1605 [Discover] "Discover",
1606 [Offer] "Offer",
1607 [Request] "Request",
1608 [Decline] "Decline",
1609 [Ack] "Ack",
1610 [Nak] "Nak",
1611 [Release] "Release",
1612 [Inform] "Inform",
1613 };
1614
1615 void
logdhcp(Req * rp)1616 logdhcp(Req *rp)
1617 {
1618 char buf[4096];
1619 char *p, *e;
1620 int i;
1621
1622 p = buf;
1623 e = buf + sizeof(buf);
1624 if(rp->dhcptype > 0 && rp->dhcptype <= Inform)
1625 p = seprint(p, e, "%s(", dhcpmsgname[rp->dhcptype]);
1626 else
1627 p = seprint(p, e, "%d(", rp->dhcptype);
1628 p = seprint(p, e, "%I->%I) xid(%ux)flag(%ux)", rp->up->raddr, rp->up->laddr,
1629 nhgetl(rp->bp->xid), nhgets(rp->bp->flags));
1630 if(rp->bp->htype == 1)
1631 p = seprint(p, e, "ea(%E)", rp->bp->chaddr);
1632 if(validip(rp->ciaddr))
1633 p = seprint(p, e, "ci(%I)", rp->ciaddr);
1634 if(validip(rp->giaddr))
1635 p = seprint(p, e, "gi(%I)", rp->giaddr);
1636 if(validip(rp->ip))
1637 p = seprint(p, e, "ip(%I)", rp->ip);
1638 if(rp->id != nil)
1639 p = seprint(p, e, "id(%s)", rp->id);
1640 if(rp->leasetime)
1641 p = seprint(p, e, "leas(%d)", rp->leasetime);
1642 if(validip(rp->server))
1643 p = seprint(p, e, "sid(%I)", rp->server);
1644 p = seprint(p, e, "need(");
1645 for(i = 0; i < sizeof(rp->requested); i++)
1646 if(rp->requested[i] != 0)
1647 p = seprint(p, e, "%s ", optname[rp->requested[i]]);
1648 p = seprint(p, e, ")");
1649 p = seprint(p, e, " %s", rp->broadcast? "broadcast": "unicast");
1650 USED(p);
1651 syslog(0, blog, "%s", buf);
1652 }
1653
1654 void
logdhcpout(Req * rp,char * type)1655 logdhcpout(Req *rp, char *type)
1656 {
1657 syslog(0, blog, "%s(%I-%I)id(%s)ci(%V)gi(%V)yi(%V)si(%V) %s",
1658 type, rp->up->laddr, rp->up->raddr, rp->id,
1659 rp->bp->ciaddr, rp->bp->giaddr, rp->bp->yiaddr, rp->bp->siaddr, optbuf);
1660 }
1661
1662 /*
1663 * if we get behind, it's useless to try answering since the sender
1664 * will probably have retransmitted with a differnt sequence number.
1665 * So dump all but the last message in the queue.
1666 */
1667 void
ding(void *,char * msg)1668 ding(void*, char *msg)
1669 {
1670 if(strstr(msg, "alarm"))
1671 noted(NCONT);
1672 else
1673 noted(NDFLT);
1674 }
1675
1676 int
readlast(int fd,uchar * buf,int len)1677 readlast(int fd, uchar *buf, int len)
1678 {
1679 int lastn, n;
1680
1681 notify(ding);
1682
1683 lastn = 0;
1684 for(;;){
1685 alarm(20);
1686 n = read(fd, buf, len);
1687 alarm(0);
1688 if(n < 0){
1689 if(lastn > 0)
1690 return lastn;
1691 break;
1692 }
1693 lastn = n;
1694 }
1695 return read(fd, buf, len);
1696 }
1697