xref: /dflybsd-src/sys/vfs/nfs/bootp_subr.c (revision f0a26983b6dd6b7880fa53aa7314918e56415aba)
1 /*
2  * Copyright (c) 1995 Gordon Ross, Adam Glass
3  * Copyright (c) 1992 Regents of the University of California.
4  * All rights reserved.
5  *
6  * This software was developed by the Computer Systems Engineering group
7  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
8  * contributed to Berkeley.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the University of
21  *	California, Lawrence Berkeley Laboratory and its contributors.
22  * 4. Neither the name of the University nor the names of its contributors
23  *    may be used to endorse or promote products derived from this software
24  *    without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36  * SUCH DAMAGE.
37  *
38  * nfs/krpc_subr.c
39  * $NetBSD: krpc_subr.c,v 1.10 1995/08/08 20:43:43 gwr Exp $
40  * $FreeBSD: src/sys/nfs/bootp_subr.c,v 1.20.2.9 2003/04/24 16:51:08 ambrisko Exp $
41  */
42 
43 #include "opt_bootp.h"
44 
45 #include <sys/param.h>
46 #include <sys/systm.h>
47 #include <sys/kernel.h>
48 #include <sys/sockio.h>
49 #include <sys/proc.h>
50 #include <sys/malloc.h>
51 #include <sys/mount.h>
52 #include <sys/mbuf.h>
53 #include <sys/socket.h>
54 #include <sys/socketvar.h>
55 #include <sys/sysctl.h>
56 #include <sys/uio.h>
57 #include <sys/fcntl.h>
58 
59 #include <net/if.h>
60 #include <net/route.h>
61 
62 #include <netinet/in.h>
63 #include <net/if_types.h>
64 #include <net/if_dl.h>
65 
66 #include "rpcv2.h"
67 #include "nfsproto.h"
68 #include "nfs.h"
69 #include "nfsdiskless.h"
70 #include "krpc.h"
71 #include "xdr_subs.h"
72 #include "nfsmountrpc.h"
73 
74 #define BOOTP_MIN_LEN		300	/* Minimum size of bootp udp packet */
75 
76 #ifndef BOOTP_SETTLE_DELAY
77 #define BOOTP_SETTLE_DELAY 3
78 #endif
79 
80 /*
81  * What is the longest we will wait before re-sending a request?
82  * Note this is also the frequency of "RPC timeout" messages.
83  * The re-send loop count sup linearly to this maximum, so the
84  * first complaint will happen after (1+2+3+4+5)=15 seconds.
85  */
86 #define	MAX_RESEND_DELAY 5	/* seconds */
87 
88 /* Definitions from RFC951 */
89 struct bootp_packet {
90 	u_int8_t op;
91 	u_int8_t htype;
92 	u_int8_t hlen;
93 	u_int8_t hops;
94 	u_int32_t xid;
95 	u_int16_t secs;
96 	u_int16_t flags;
97 	struct in_addr ciaddr;
98 	struct in_addr yiaddr;
99 	struct in_addr siaddr;
100 	struct in_addr giaddr;
101 	unsigned char chaddr[16];
102 	char sname[64];
103 	char file[128];
104 	unsigned char vend[1222];
105 };
106 
107 struct bootpc_ifcontext {
108 	struct bootpc_ifcontext *next;
109 	struct bootp_packet call;
110 	struct bootp_packet reply;
111 	int replylen;
112 	int overload;
113 	struct socket *so;
114 	struct ifreq ireq;
115 	struct ifnet *ifp;
116 	struct sockaddr_dl *sdl;
117 	struct sockaddr_in myaddr;
118 	struct sockaddr_in netmask;
119 	struct sockaddr_in gw;
120 	struct sockaddr_in broadcast;	/* Different for each interface */
121 	int gotgw;
122 	int gotnetmask;
123 	int gotrootpath;
124 	int outstanding;
125 	int sentmsg;
126 	u_int32_t xid;
127 	enum {
128 		IF_BOOTP_UNRESOLVED,
129 		IF_BOOTP_RESOLVED,
130 		IF_BOOTP_FAILED,
131 		IF_DHCP_UNRESOLVED,
132 		IF_DHCP_OFFERED,
133 		IF_DHCP_RESOLVED,
134 		IF_DHCP_FAILED,
135 	} state;
136 	int dhcpquerytype;		/* dhcp type sent */
137 	struct in_addr dhcpserver;
138 	int gotdhcpserver;
139 };
140 
141 #define TAG_MAXLEN 1024
142 struct bootpc_tagcontext {
143 	char buf[TAG_MAXLEN + 1];
144 	int overload;
145 	int badopt;
146 	int badtag;
147 	int foundopt;
148 	int taglen;
149 };
150 
151 struct bootpc_globalcontext {
152 	struct bootpc_ifcontext *interfaces;
153 	struct bootpc_ifcontext *lastinterface;
154 	u_int32_t xid;
155 	int gotrootpath;
156 	int gotswappath;
157 	int gotgw;
158 	int ifnum;
159 	int secs;
160 	int starttime;
161 	struct bootp_packet reply;
162 	int replylen;
163 	struct bootpc_ifcontext *setswapfs;
164 	struct bootpc_ifcontext *setrootfs;
165 	struct bootpc_ifcontext *sethostname;
166 	char lookup_path[24];
167 	struct bootpc_tagcontext tmptag;
168 	struct bootpc_tagcontext tag;
169 };
170 
171 #define IPPORT_BOOTPC 68
172 #define IPPORT_BOOTPS 67
173 
174 #define BOOTP_REQUEST 1
175 #define BOOTP_REPLY 2
176 
177 /* Common tags */
178 #define TAG_PAD		  0  /* Pad option, implicit length 1 */
179 #define TAG_SUBNETMASK	  1  /* RFC 950 subnet mask */
180 #define TAG_ROUTERS	  3  /* Routers (in order of preference) */
181 #define TAG_HOSTNAME	 12  /* Client host name */
182 #define TAG_ROOT	 17  /* Root path */
183 
184 /* DHCP specific tags */
185 #define TAG_OVERLOAD	 52  /* Option Overload */
186 #define TAG_MAXMSGSIZE   57  /* Maximum DHCP Message Size */
187 
188 #define TAG_END		255  /* End Option (i.e. no more options) */
189 
190 /* Overload values */
191 #define OVERLOAD_FILE     1
192 #define OVERLOAD_SNAME    2
193 
194 /* Site specific tags: */
195 #define TAG_SWAP	128
196 #define TAG_SWAPSIZE	129
197 #define TAG_ROOTOPTS	130
198 #define TAG_SWAPOPTS	131
199 #define TAG_COOKIE	134	/* ascii info for userland, exported via sysctl */
200 
201 #define TAG_DHCP_MSGTYPE 53
202 #define TAG_DHCP_REQ_ADDR 50
203 #define TAG_DHCP_SERVERID 54
204 #define TAG_DHCP_LEASETIME 51
205 
206 #define TAG_VENDOR_INDENTIFIER 60
207 
208 #define DHCP_NOMSG    0
209 #define DHCP_DISCOVER 1
210 #define DHCP_OFFER    2
211 #define DHCP_REQUEST  3
212 #define DHCP_ACK      5
213 
214 static char bootp_cookie[128];
215 SYSCTL_STRING(_kern, OID_AUTO, bootp_cookie, CTLFLAG_RD,
216 	bootp_cookie, 0, "Cookie (T134) supplied by bootp server");
217 
218 /* mountd RPC */
219 static void print_in_addr(struct in_addr addr);
220 static void print_sin_addr(struct sockaddr_in *addr);
221 static void clear_sinaddr(struct sockaddr_in *sin);
222 static
223 struct bootpc_ifcontext *allocifctx(struct bootpc_globalcontext *gctx);
224 static void bootpc_compose_query(struct bootpc_ifcontext *ifctx,
225 				 struct bootpc_globalcontext *gctx,
226 				 struct thread *td);
227 static unsigned char *bootpc_tag(struct bootpc_tagcontext *tctx,
228 				 struct bootp_packet *bp, int len, int tag);
229 static void bootpc_tag_helper(struct bootpc_tagcontext *tctx,
230 			      unsigned char *start, int len, int tag);
231 
232 #ifdef BOOTP_DEBUG
233 void bootpboot_p_sa(struct sockaddr *sa,struct sockaddr *ma);
234 void bootpboot_p_ma(struct sockaddr *ma);
235 void bootpboot_p_rtentry(struct rtentry *rt);
236 void bootpboot_p_tree(struct radix_node *rn);
237 void bootpboot_p_rtlist(void);
238 void bootpboot_p_if(struct ifnet *ifp, struct ifaddr *ifa);
239 void bootpboot_p_iflist(void);
240 #endif
241 
242 static int  bootpc_call(struct bootpc_globalcontext *gctx,
243 			struct thread *td);
244 
245 static int bootpc_fakeup_interface(struct bootpc_ifcontext *ifctx,
246 				   struct bootpc_globalcontext *gctx,
247 				   struct thread *td);
248 
249 static int bootpc_adjust_interface(struct bootpc_ifcontext *ifctx,
250 				   struct bootpc_globalcontext *gctx,
251 				   struct thread *td);
252 
253 static void bootpc_decode_reply(struct nfsv3_diskless *nd,
254 				struct bootpc_ifcontext *ifctx,
255 				struct bootpc_globalcontext *gctx);
256 
257 static int bootpc_received(struct bootpc_globalcontext *gctx,
258 			   struct bootpc_ifcontext *ifctx);
259 
260 static __inline int bootpc_ifctx_isresolved(struct bootpc_ifcontext *ifctx);
261 static __inline int bootpc_ifctx_isunresolved(struct bootpc_ifcontext *ifctx);
262 static __inline int bootpc_ifctx_isfailed(struct bootpc_ifcontext *ifctx);
263 
264 void bootpc_init(void);
265 
266 /*
267  * In order to have multiple active interfaces with address 0.0.0.0
268  * and be able to send data to a selected interface, we perform
269  * some tricks:
270  *
271  *  - The 'broadcast' address is different for each interface.
272  *
273  *  - We temporarily add routing pointing 255.255.255.255 to the
274  *    selected interface broadcast address, thus the packet sent
275  *    goes to that interface.
276  */
277 
278 #ifdef BOOTP_DEBUG
279 void
280 bootpboot_p_sa(struct sockaddr *sa, struct sockaddr *ma)
281 {
282 	if (sa == NULL) {
283 		kprintf("(sockaddr *) <null>");
284 		return;
285 	}
286 	switch (sa->sa_family) {
287 	case AF_INET:
288 	{
289 		struct sockaddr_in *sin;
290 
291 		sin = (struct sockaddr_in *) sa;
292 		kprintf("inet ");
293 		print_sin_addr(sin);
294 		if (ma != NULL) {
295 			sin = (struct sockaddr_in *) ma;
296 			kprintf(" mask ");
297 			print_sin_addr(sin);
298 		}
299 	}
300 	break;
301 	case AF_LINK:
302 	{
303 		struct sockaddr_dl *sli;
304 		int i;
305 
306 		sli = (struct sockaddr_dl *) sa;
307 		kprintf("link %.*s ", sli->sdl_nlen, sli->sdl_data);
308 		for (i = 0; i < sli->sdl_alen; i++) {
309 			if (i > 0)
310 				kprintf(":");
311 			kprintf("%x", ((unsigned char *) LLADDR(sli))[i]);
312 		}
313 	}
314 	break;
315 	default:
316 		kprintf("af%d", sa->sa_family);
317 	}
318 }
319 
320 
321 void
322 bootpboot_p_ma(struct sockaddr *ma)
323 {
324 	if (ma == NULL) {
325 		kprintf("<null>");
326 		return;
327 	}
328 	kprintf("%x", *(int *)ma);
329 }
330 
331 
332 void
333 bootpboot_p_rtentry(struct rtentry *rt)
334 {
335 	bootpboot_p_sa(rt_key(rt), rt_mask(rt));
336 	kprintf(" ");
337 	bootpboot_p_ma(rt->rt_genmask);
338 	kprintf(" ");
339 	bootpboot_p_sa(rt->rt_gateway, NULL);
340 	kprintf(" ");
341 	kprintf("flags %x", (unsigned short) rt->rt_flags);
342 	kprintf(" %d", (int) rt->rt_rmx.rmx_expire);
343 	kprintf(" %s\n", if_name(rt->rt_ifp));
344 }
345 
346 
347 void
348 bootpboot_p_tree(struct radix_node *rn)
349 {
350 	while (rn != NULL) {
351 		if (rn->rn_bit < 0) {
352 			if ((rn->rn_flags & RNF_ROOT) != 0) {
353 			} else {
354 				bootpboot_p_rtentry((struct rtentry *) rn);
355 			}
356 			rn = rn->rn_dupedkey;
357 		} else {
358 			bootpboot_p_tree(rn->rn_left);
359 			bootpboot_p_tree(rn->rn_right);
360 			return;
361 		}
362 	}
363 }
364 
365 
366 void
367 bootpboot_p_rtlist(void)
368 {
369 	kprintf("Routing table:\n");
370 	bootpboot_p_tree(rt_tables[AF_INET]->rnh_treetop);
371 }
372 
373 
374 void
375 bootpboot_p_if(struct ifnet *ifp, struct ifaddr *ifa)
376 {
377 	kprintf("%s flags %x, addr ",
378 	       if_name(ifp),
379 	       (unsigned short) ifp->if_flags);
380 	print_sin_addr((struct sockaddr_in *) ifa->ifa_addr);
381 	kprintf(", broadcast ");
382 	print_sin_addr((struct sockaddr_in *) ifa->ifa_dstaddr);
383 	kprintf(", netmask ");
384 	print_sin_addr((struct sockaddr_in *) ifa->ifa_netmask);
385 	kprintf("\n");
386 }
387 
388 
389 void
390 bootpboot_p_iflist(void)
391 {
392 	struct ifnet *ifp;
393 	struct ifaddr_container *ifac;
394 
395 	kprintf("Interface list:\n");
396 	TAILQ_FOREACH(ifp, &ifnet, if_link) {
397 		TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) {
398 			struct ifaddr *ifa = ifac->ifa;
399 
400 			if (ifa->ifa_addr->sa_family == AF_INET)
401 				bootpboot_p_if(ifp, ifa);
402 		}
403 	}
404 }
405 #endif /* defined(BOOTP_DEBUG) */
406 
407 
408 static void
409 clear_sinaddr(struct sockaddr_in *sin)
410 {
411 	bzero(sin, sizeof(*sin));
412 	sin->sin_len = sizeof(*sin);
413 	sin->sin_family = AF_INET;
414 	sin->sin_addr.s_addr = INADDR_ANY; /* XXX: htonl(INAADDR_ANY) ? */
415 	sin->sin_port = 0;
416 }
417 
418 
419 static struct bootpc_ifcontext *
420 allocifctx(struct bootpc_globalcontext *gctx)
421 {
422 	struct bootpc_ifcontext *ifctx;
423 	ifctx = (struct bootpc_ifcontext *) kmalloc(sizeof(*ifctx),
424 						   M_TEMP, M_WAITOK);
425 	bzero(ifctx, sizeof(*ifctx));
426 	ifctx->xid = gctx->xid;
427 #ifdef BOOTP_NO_DHCP
428 	ifctx->state = IF_BOOTP_UNRESOLVED;
429 #else
430 	ifctx->state = IF_DHCP_UNRESOLVED;
431 #endif
432 	gctx->xid += 0x100;
433 	return ifctx;
434 }
435 
436 
437 static __inline int
438 bootpc_ifctx_isresolved(struct bootpc_ifcontext *ifctx)
439 {
440 	if (ifctx->state == IF_BOOTP_RESOLVED ||
441 	    ifctx->state == IF_DHCP_RESOLVED)
442 		return 1;
443 	return 0;
444 }
445 
446 
447 static __inline int
448 bootpc_ifctx_isunresolved(struct bootpc_ifcontext *ifctx)
449 {
450 	if (ifctx->state == IF_BOOTP_UNRESOLVED ||
451 	    ifctx->state == IF_DHCP_UNRESOLVED)
452 		return 1;
453 	return 0;
454 }
455 
456 
457 static __inline int
458 bootpc_ifctx_isfailed(struct bootpc_ifcontext *ifctx)
459 {
460 	if (ifctx->state == IF_BOOTP_FAILED ||
461 	    ifctx->state == IF_DHCP_FAILED)
462 		return 1;
463 	return 0;
464 }
465 
466 
467 static int
468 bootpc_received(struct bootpc_globalcontext *gctx,
469 		struct bootpc_ifcontext *ifctx)
470 {
471 	unsigned char dhcpreplytype;
472 	char *p;
473 	/*
474 	 * Need timeout for fallback to less
475 	 * desirable alternative.
476 	 */
477 
478 
479 	/* This call used for the side effect (badopt flag) */
480 	(void) bootpc_tag(&gctx->tmptag, &gctx->reply,
481 			  gctx->replylen,
482 			  TAG_END);
483 
484 	/* If packet is invalid, ignore it */
485 	if (gctx->tmptag.badopt != 0)
486 		return 0;
487 
488 	p = bootpc_tag(&gctx->tmptag, &gctx->reply,
489 		       gctx->replylen, TAG_DHCP_MSGTYPE);
490 	if (p != NULL)
491 		dhcpreplytype = *p;
492 	else
493 		dhcpreplytype = DHCP_NOMSG;
494 
495 	switch (ifctx->dhcpquerytype) {
496 	case DHCP_DISCOVER:
497 		if (dhcpreplytype != DHCP_OFFER 	/* Normal DHCP offer */
498 #ifndef BOOTP_FORCE_DHCP
499 		    && dhcpreplytype != DHCP_NOMSG	/* Fallback to BOOTP */
500 #endif
501 			)
502 			return 0;
503 		break;
504 	case DHCP_REQUEST:
505 		if (dhcpreplytype != DHCP_ACK)
506 			return 0;
507 		/* fall through */
508 	case DHCP_NOMSG:
509 		break;
510 	}
511 
512 
513 	/* Ignore packet unless it gives us a root tag we didn't have */
514 
515 	if ((ifctx->state == IF_BOOTP_RESOLVED ||
516 	     (ifctx->dhcpquerytype == DHCP_DISCOVER &&
517 	      (ifctx->state == IF_DHCP_OFFERED ||
518 	       ifctx->state == IF_DHCP_RESOLVED))) &&
519 	    (bootpc_tag(&gctx->tmptag, &ifctx->reply,
520 			ifctx->replylen,
521 			TAG_ROOT) != NULL ||
522 	     bootpc_tag(&gctx->tmptag, &gctx->reply,
523 			gctx->replylen,
524 			TAG_ROOT) == NULL))
525 		return 0;
526 
527 	bcopy(&gctx->reply,
528 	      &ifctx->reply,
529 	      gctx->replylen);
530 	ifctx->replylen = gctx->replylen;
531 
532 	/* XXX: Only reset if 'perfect' response */
533 	if (ifctx->state == IF_BOOTP_UNRESOLVED)
534 		ifctx->state = IF_BOOTP_RESOLVED;
535 	else if (ifctx->state == IF_DHCP_UNRESOLVED &&
536 		 ifctx->dhcpquerytype == DHCP_DISCOVER) {
537 		if (dhcpreplytype == DHCP_OFFER)
538 			ifctx->state = IF_DHCP_OFFERED;
539 		else
540 			ifctx->state = IF_BOOTP_RESOLVED;	/* Fallback */
541 	} else if (ifctx->state == IF_DHCP_OFFERED &&
542 		   ifctx->dhcpquerytype == DHCP_REQUEST)
543 		ifctx->state = IF_DHCP_RESOLVED;
544 
545 
546 	if (ifctx->dhcpquerytype == DHCP_DISCOVER &&
547 	    ifctx->state != IF_BOOTP_RESOLVED) {
548 		p = bootpc_tag(&gctx->tmptag, &ifctx->reply,
549 			       ifctx->replylen, TAG_DHCP_SERVERID);
550 		if (p != NULL && gctx->tmptag.taglen == 4) {
551 			memcpy(&ifctx->dhcpserver, p, 4);
552 			ifctx->gotdhcpserver = 1;
553 		} else
554 			ifctx->gotdhcpserver = 0;
555 		return 1;
556 	}
557 
558 	ifctx->gotrootpath = (bootpc_tag(&gctx->tmptag, &ifctx->reply,
559 					 ifctx->replylen,
560 					 TAG_ROOT) != NULL);
561 	ifctx->gotgw = (bootpc_tag(&gctx->tmptag, &ifctx->reply,
562 				   ifctx->replylen,
563 				   TAG_ROUTERS) != NULL);
564 	ifctx->gotnetmask = (bootpc_tag(&gctx->tmptag, &ifctx->reply,
565 					ifctx->replylen,
566 					TAG_SUBNETMASK) != NULL);
567 	return 1;
568 }
569 
570 static int
571 bootpc_call(struct bootpc_globalcontext *gctx, struct thread *td)
572 {
573 	struct socket *so;
574 	struct sockaddr_in *sin, dst;
575 	struct uio auio;
576 	struct sockopt sopt;
577 	struct iovec aio;
578 	int error, on, rcvflg, timo, len;
579 	time_t atimo;
580 	time_t rtimo;
581 	struct timeval tv;
582 	struct bootpc_ifcontext *ifctx;
583 	int outstanding;
584 	int gotrootpath;
585 	int retry;
586 	const char *s;
587 
588 	/*
589 	 * Create socket and set its recieve timeout.
590 	 */
591 	error = socreate(AF_INET, &so, SOCK_DGRAM, 0, td);
592 	if (error != 0)
593 		goto out;
594 
595 	tv.tv_sec = 1;
596 	tv.tv_usec = 0;
597 	bzero(&sopt, sizeof(sopt));
598 	sopt.sopt_level = SOL_SOCKET;
599 	sopt.sopt_name = SO_RCVTIMEO;
600 	sopt.sopt_val = &tv;
601 	sopt.sopt_valsize = sizeof tv;
602 
603 	error = sosetopt(so, &sopt);
604 	if (error != 0)
605 		goto out;
606 
607 	/*
608 	 * Enable broadcast.
609 	 */
610 	on = 1;
611 	sopt.sopt_name = SO_BROADCAST;
612 	sopt.sopt_val = &on;
613 	sopt.sopt_valsize = sizeof on;
614 
615 	error = sosetopt(so, &sopt);
616 	if (error != 0)
617 		goto out;
618 
619 	/*
620 	 * Disable routing.
621 	 */
622 
623 	on = 1;
624 	sopt.sopt_name = SO_DONTROUTE;
625 	sopt.sopt_val = &on;
626 	sopt.sopt_valsize = sizeof on;
627 
628 	error = sosetopt(so, &sopt);
629 	if (error != 0)
630 		goto out;
631 
632 	/*
633 	 * Bind the local endpoint to a bootp client port.
634 	 */
635 	sin = &dst;
636 	clear_sinaddr(sin);
637 	sin->sin_port = htons(IPPORT_BOOTPC);
638 	error = sobind(so, (struct sockaddr *)sin, td);
639 	if (error != 0) {
640 		kprintf("bind failed\n");
641 		goto out;
642 	}
643 
644 	/*
645 	 * Setup socket address for the server.
646 	 */
647 	sin = &dst;
648 	clear_sinaddr(sin);
649 	sin->sin_addr.s_addr = INADDR_BROADCAST;
650 	sin->sin_port = htons(IPPORT_BOOTPS);
651 
652 	/*
653 	 * Send it, repeatedly, until a reply is received,
654 	 * but delay each re-send by an increasing amount.
655 	 * If the delay hits the maximum, start complaining.
656 	 */
657 	timo = 0;
658 	rtimo = 0;
659 	for (;;) {
660 
661 		outstanding = 0;
662 		gotrootpath = 0;
663 
664 		for (ifctx = gctx->interfaces;
665 		     ifctx != NULL;
666 		     ifctx = ifctx->next) {
667 			if (bootpc_ifctx_isresolved(ifctx) != 0 &&
668 			    bootpc_tag(&gctx->tmptag, &ifctx->reply,
669 				       ifctx->replylen,
670 				       TAG_ROOT) != NULL)
671 				gotrootpath = 1;
672 		}
673 
674 		for (ifctx = gctx->interfaces;
675 		     ifctx != NULL;
676 		     ifctx = ifctx->next) {
677 			ifctx->outstanding = 0;
678 			if (bootpc_ifctx_isresolved(ifctx)  != 0 &&
679 			    gotrootpath != 0) {
680 				continue;
681 			}
682 			if (bootpc_ifctx_isfailed(ifctx) != 0)
683 				continue;
684 
685 			outstanding++;
686 			ifctx->outstanding = 1;
687 
688 			/* Proceed to next step in DHCP negotiation */
689 			if ((ifctx->state == IF_DHCP_OFFERED &&
690 			     ifctx->dhcpquerytype != DHCP_REQUEST) ||
691 			    (ifctx->state == IF_DHCP_UNRESOLVED &&
692 			     ifctx->dhcpquerytype != DHCP_DISCOVER) ||
693 			    (ifctx->state == IF_BOOTP_UNRESOLVED &&
694 			     ifctx->dhcpquerytype != DHCP_NOMSG)) {
695 				ifctx->sentmsg = 0;
696 				bootpc_compose_query(ifctx, gctx, td);
697 			}
698 
699 			/* Send BOOTP request (or re-send). */
700 
701 			if (ifctx->sentmsg == 0) {
702 				switch(ifctx->dhcpquerytype) {
703 				case DHCP_DISCOVER:
704 					s = "DHCP Discover";
705 					break;
706 				case DHCP_REQUEST:
707 					s = "DHCP Request";
708 					break;
709 				case DHCP_NOMSG:
710 				default:
711 					s = "BOOTP Query";
712 					break;
713 				}
714 				kprintf("Sending %s packet from "
715 				       "interface %s (%*D)\n",
716 				       s,
717 				       ifctx->ireq.ifr_name,
718 				       ifctx->sdl->sdl_alen,
719 				       (unsigned char *) LLADDR(ifctx->sdl),
720 				       ":");
721 				ifctx->sentmsg = 1;
722 			}
723 
724 			aio.iov_base = (caddr_t) &ifctx->call;
725 			aio.iov_len = sizeof(ifctx->call);
726 
727 			auio.uio_iov = &aio;
728 			auio.uio_iovcnt = 1;
729 			auio.uio_segflg = UIO_SYSSPACE;
730 			auio.uio_rw = UIO_WRITE;
731 			auio.uio_offset = 0;
732 			auio.uio_resid = sizeof(ifctx->call);
733 			auio.uio_td = td;
734 
735 			/* Set netmask to 0.0.0.0 */
736 
737 			sin = (struct sockaddr_in *) &ifctx->ireq.ifr_addr;
738 			clear_sinaddr(sin);
739 			error = ifioctl(ifctx->so, SIOCSIFNETMASK,
740 					(caddr_t) &ifctx->ireq, proc0.p_ucred);
741 			if (error != 0)
742 				panic("bootpc_call:"
743 				      "set if netmask, error=%d",
744 				      error);
745 
746 			error = sosend(so, (struct sockaddr *) &dst,
747 				       &auio, NULL, NULL, 0, td);
748 			if (error != 0) {
749 				kprintf("bootpc_call: sosend: %d state %08x\n",
750 				       error, (int) so->so_state);
751 			}
752 
753 			/* XXX: Is this needed ? */
754 			tsleep(&error, 0, "bootpw", 10);
755 
756 			/* Set netmask to 255.0.0.0 */
757 
758 			sin = (struct sockaddr_in *) &ifctx->ireq.ifr_addr;
759 			clear_sinaddr(sin);
760 			sin->sin_addr.s_addr = htonl(0xff000000u);
761 			error = ifioctl(ifctx->so, SIOCSIFNETMASK,
762 					(caddr_t) &ifctx->ireq, proc0.p_ucred);
763 			if (error != 0)
764 				panic("bootpc_call:"
765 				      "set if netmask, error=%d",
766 				      error);
767 
768 		}
769 
770 		if (outstanding == 0 &&
771 		    (rtimo == 0 || time_second >= rtimo)) {
772 			error = 0;
773 			goto gotreply;
774 		}
775 
776 		/* Determine new timeout. */
777 		if (timo < MAX_RESEND_DELAY)
778 			timo++;
779 		else {
780 			kprintf("DHCP/BOOTP timeout for server ");
781 			print_sin_addr(&dst);
782 			kprintf("\n");
783 		}
784 
785 		/*
786 		 * Wait for up to timo seconds for a reply.
787 		 * The socket receive timeout was set to 1 second.
788 		 */
789 		atimo = timo + time_second;
790 		while (time_second < atimo) {
791 			aio.iov_base = (caddr_t) &gctx->reply;
792 			aio.iov_len = sizeof(gctx->reply);
793 
794 			auio.uio_iov = &aio;
795 			auio.uio_iovcnt = 1;
796 			auio.uio_segflg = UIO_SYSSPACE;
797 			auio.uio_rw = UIO_READ;
798 			auio.uio_offset = 0;
799 			auio.uio_resid = sizeof(gctx->reply);
800 			auio.uio_td = td;
801 
802 			rcvflg = 0;
803 			error = soreceive(so, NULL, &auio,
804 					  NULL, NULL, &rcvflg);
805 			gctx->secs = time_second - gctx->starttime;
806 			for (ifctx = gctx->interfaces;
807 			     ifctx != NULL;
808 			     ifctx = ifctx->next) {
809 				if (bootpc_ifctx_isresolved(ifctx) != 0 ||
810 				    bootpc_ifctx_isfailed(ifctx) != 0)
811 					continue;
812 
813 				ifctx->call.secs = htons(gctx->secs);
814 			}
815 			if (error == EWOULDBLOCK)
816 				continue;
817 			if (error != 0)
818 				goto out;
819 			len = sizeof(gctx->reply) - auio.uio_resid;
820 
821 			/* Do we have the required number of bytes ? */
822 			if (len < BOOTP_MIN_LEN)
823 				continue;
824 			gctx->replylen = len;
825 
826 			/* Is it a reply? */
827 			if (gctx->reply.op != BOOTP_REPLY)
828 				continue;
829 
830 			/* Is this an answer to our query */
831 			for (ifctx = gctx->interfaces;
832 			     ifctx != NULL;
833 			     ifctx = ifctx->next) {
834 				if (gctx->reply.xid != ifctx->call.xid)
835 					continue;
836 
837 				/* Same HW address size ? */
838 				if (gctx->reply.hlen != ifctx->call.hlen)
839 					continue;
840 
841 				/* Correct HW address ? */
842 				if (bcmp(gctx->reply.chaddr,
843 					 ifctx->call.chaddr,
844 					 ifctx->call.hlen) != 0)
845 					continue;
846 
847 				break;
848 			}
849 
850 			if (ifctx != NULL) {
851 				s =  bootpc_tag(&gctx->tmptag,
852 						&gctx->reply,
853 						gctx->replylen,
854 						TAG_DHCP_MSGTYPE);
855 				if (s != NULL) {
856 					switch (*s) {
857 					case DHCP_OFFER:
858 						s = "DHCP Offer";
859 						break;
860 					case DHCP_ACK:
861 						s = "DHCP Ack";
862 						break;
863 					default:
864 						s = "DHCP (unexpected)";
865 						break;
866 					}
867 				} else
868 					s = "BOOTP Reply";
869 
870 				kprintf("Received %s packet"
871 				       " on %s from ",
872 				       s,
873 				       ifctx->ireq.ifr_name);
874 				print_in_addr(gctx->reply.siaddr);
875 				if (gctx->reply.giaddr.s_addr !=
876 				    htonl(INADDR_ANY)) {
877 					kprintf(" via ");
878 					print_in_addr(gctx->reply.giaddr);
879 				}
880 				if (bootpc_received(gctx, ifctx) != 0) {
881 					kprintf(" (accepted)");
882 					if (ifctx->outstanding) {
883 						ifctx->outstanding = 0;
884 						outstanding--;
885 					}
886 					/* Network settle delay */
887 					if (outstanding == 0)
888 						atimo = time_second +
889 							BOOTP_SETTLE_DELAY;
890 				} else
891 					kprintf(" (ignored)");
892 				if (ifctx->gotrootpath) {
893 					gotrootpath = 1;
894 					rtimo = time_second +
895 						BOOTP_SETTLE_DELAY;
896 					kprintf(" (got root path)");
897 				} else
898 					kprintf(" (no root path)");
899 				kprintf("\n");
900 			}
901 		} /* while secs */
902 #ifdef BOOTP_TIMEOUT
903 		if (gctx->secs > BOOTP_TIMEOUT && BOOTP_TIMEOUT > 0)
904 			break;
905 #endif
906 		/* Force a retry if halfway in DHCP negotiation */
907 		retry = 0;
908 		for (ifctx = gctx->interfaces; ifctx != NULL;
909 		     ifctx = ifctx->next) {
910 			if (ifctx->state == IF_DHCP_OFFERED) {
911 				if (ifctx->dhcpquerytype == DHCP_DISCOVER)
912 					retry = 1;
913 				else
914 					ifctx->state = IF_DHCP_UNRESOLVED;
915 			}
916 		}
917 
918 		if (retry != 0)
919 			continue;
920 
921 		if (gotrootpath != 0) {
922 			gctx->gotrootpath = gotrootpath;
923 			if (rtimo != 0 && time_second >= rtimo)
924 				break;
925 		}
926 	} /* forever send/receive */
927 
928 	/*
929 	 * XXX: These are errors of varying seriousness being silently
930 	 * ignored
931 	 */
932 
933 	for (ifctx = gctx->interfaces; ifctx != NULL; ifctx = ifctx->next) {
934 		if (bootpc_ifctx_isresolved(ifctx) == 0) {
935 			kprintf("%s timeout for interface %s\n",
936 			       ifctx->dhcpquerytype != DHCP_NOMSG ?
937 			       "DHCP" : "BOOTP",
938 			       ifctx->ireq.ifr_name);
939 		}
940 	}
941 	if (gctx->gotrootpath != 0) {
942 #if 0
943 		kprintf("Got a root path, ignoring remaining timeout\n");
944 #endif
945 		error = 0;
946 		goto out;
947 	}
948 #ifndef BOOTP_NFSROOT
949 	for (ifctx = gctx->interfaces; ifctx != NULL; ifctx = ifctx->next) {
950 		if (bootpc_ifctx_isresolved(ifctx) != 0) {
951 			error = 0;
952 			goto out;
953 		}
954 	}
955 #endif
956 	error = ETIMEDOUT;
957 	goto out;
958 
959 gotreply:
960 out:
961 	soclose(so, FNONBLOCK);
962 	return error;
963 }
964 
965 
966 static int
967 bootpc_fakeup_interface(struct bootpc_ifcontext *ifctx,
968 			struct bootpc_globalcontext *gctx,
969 			struct thread *td)
970 {
971 	struct ifaddr_container *ifac;
972 	struct sockaddr_in *sin;
973 	int error;
974 
975 	struct ifreq *ireq;
976 	struct socket *so;
977 	struct sockaddr_dl *sdl;
978 
979 	error = socreate(AF_INET, &ifctx->so, SOCK_DGRAM, 0, td);
980 	if (error != 0)
981 		panic("nfs_boot: socreate, error=%d", error);
982 
983 	ireq = &ifctx->ireq;
984 	so = ifctx->so;
985 
986 	/*
987 	 * Bring up the interface.
988 	 *
989 	 * Get the old interface flags and or IFF_UP into them; if
990 	 * IFF_UP set blindly, interface selection can be clobbered.
991 	 */
992 	error = ifioctl(so, SIOCGIFFLAGS, (caddr_t)ireq, proc0.p_ucred);
993 	if (error != 0)
994 		panic("bootpc_fakeup_interface: GIFFLAGS, error=%d", error);
995 	ireq->ifr_flags |= IFF_UP;
996 	error = ifioctl(so, SIOCSIFFLAGS, (caddr_t)ireq, proc0.p_ucred);
997 	if (error != 0)
998 		panic("bootpc_fakeup_interface: SIFFLAGS, error=%d", error);
999 
1000 	/*
1001 	 * Do enough of ifconfig(8) so that the chosen interface
1002 	 * can talk to the servers.  (just set the address)
1003 	 */
1004 
1005 	/* addr is 0.0.0.0 */
1006 
1007 	sin = (struct sockaddr_in *) &ireq->ifr_addr;
1008 	clear_sinaddr(sin);
1009 	error = ifioctl(so, SIOCSIFADDR, (caddr_t) ireq, proc0.p_ucred);
1010 	if (error != 0 && (error != EEXIST || ifctx == gctx->interfaces))
1011 		panic("bootpc_fakeup_interface: "
1012 		      "set if addr, error=%d", error);
1013 
1014 	/* netmask is 255.0.0.0 */
1015 
1016 	sin = (struct sockaddr_in *) &ireq->ifr_addr;
1017 	clear_sinaddr(sin);
1018 	sin->sin_addr.s_addr = htonl(0xff000000u);
1019 	error = ifioctl(so, SIOCSIFNETMASK, (caddr_t)ireq, proc0.p_ucred);
1020 	if (error != 0)
1021 		panic("bootpc_fakeup_interface: set if netmask, error=%d",
1022 		      error);
1023 
1024 	/* Broadcast is 255.255.255.255 */
1025 
1026 	sin = (struct sockaddr_in *)&ireq->ifr_addr;
1027 	clear_sinaddr(sin);
1028 	clear_sinaddr(&ifctx->broadcast);
1029 	sin->sin_addr.s_addr = htonl(INADDR_BROADCAST);
1030 	ifctx->broadcast.sin_addr.s_addr = sin->sin_addr.s_addr;
1031 
1032 	error = ifioctl(so, SIOCSIFBRDADDR, (caddr_t)ireq, proc0.p_ucred);
1033 	if (error != 0 && error != EADDRNOTAVAIL)
1034 		panic("bootpc_fakeup_interface: "
1035 		      "set if broadcast addr, error=%d",
1036 		      error);
1037 	error = 0;
1038 
1039 	/* Get HW address */
1040 
1041 	sdl = NULL;
1042 	TAILQ_FOREACH(ifac, &ifctx->ifp->if_addrheads[mycpuid], ifa_link) {
1043 		struct ifaddr *ifa = ifac->ifa;
1044 
1045 		if (ifa->ifa_addr->sa_family == AF_LINK &&
1046 		    (sdl = ((struct sockaddr_dl *) ifa->ifa_addr)) != NULL &&
1047 		    sdl->sdl_type == IFT_ETHER)
1048 			break;
1049 	}
1050 
1051 	if (sdl == NULL)
1052 		panic("bootpc: Unable to find HW address for %s",
1053 		      ifctx->ireq.ifr_name);
1054 	ifctx->sdl = sdl;
1055 
1056 	return error;
1057 }
1058 
1059 
1060 static int
1061 bootpc_adjust_interface(struct bootpc_ifcontext *ifctx,
1062 			struct bootpc_globalcontext *gctx,
1063 			struct thread *td)
1064 {
1065 	int error;
1066 	struct sockaddr_in defdst;
1067 	struct sockaddr_in defmask;
1068 	struct sockaddr_in *sin;
1069 
1070 	struct ifreq *ireq;
1071 	struct socket *so;
1072 	struct sockaddr_in *myaddr;
1073 	struct sockaddr_in *netmask;
1074 	struct sockaddr_in *gw;
1075 
1076 	ireq = &ifctx->ireq;
1077 	so = ifctx->so;
1078 	myaddr = &ifctx->myaddr;
1079 	netmask = &ifctx->netmask;
1080 	gw = &ifctx->gw;
1081 
1082 	if (bootpc_ifctx_isresolved(ifctx) == 0) {
1083 
1084 		/* Shutdown interfaces where BOOTP failed */
1085 
1086 		kprintf("Shutdown interface %s\n", ifctx->ireq.ifr_name);
1087 		error = ifioctl(so, SIOCGIFFLAGS, (caddr_t)ireq, proc0.p_ucred);
1088 		if (error != 0)
1089 			panic("bootpc_adjust_interface: "
1090 			      "SIOCGIFFLAGS, error=%d", error);
1091 		ireq->ifr_flags &= ~IFF_UP;
1092 		error = ifioctl(so, SIOCSIFFLAGS, (caddr_t)ireq, proc0.p_ucred);
1093 		if (error != 0)
1094 			panic("bootpc_adjust_interface: "
1095 			      "SIOCSIFFLAGS, error=%d", error);
1096 
1097 		sin = (struct sockaddr_in *) &ireq->ifr_addr;
1098 		clear_sinaddr(sin);
1099 		error = ifioctl(so, SIOCDIFADDR, (caddr_t) ireq, proc0.p_ucred);
1100 		if (error != 0 && (error != EADDRNOTAVAIL ||
1101 				   ifctx == gctx->interfaces))
1102 			panic("bootpc_adjust_interface: "
1103 			      "SIOCDIFADDR, error=%d", error);
1104 
1105 		return 0;
1106 	}
1107 
1108 	kprintf("Adjusted interface %s\n", ifctx->ireq.ifr_name);
1109 	/*
1110 	 * Do enough of ifconfig(8) so that the chosen interface
1111 	 * can talk to the servers.  (just set the address)
1112 	 */
1113 	bcopy(netmask, &ireq->ifr_addr, sizeof(*netmask));
1114 	error = ifioctl(so, SIOCSIFNETMASK, (caddr_t) ireq, proc0.p_ucred);
1115 	if (error != 0)
1116 		panic("bootpc_adjust_interface: "
1117 		      "set if netmask, error=%d", error);
1118 
1119 	/* Broadcast is with host part of IP address all 1's */
1120 
1121 	sin = (struct sockaddr_in *) &ireq->ifr_addr;
1122 	clear_sinaddr(sin);
1123 	sin->sin_addr.s_addr = myaddr->sin_addr.s_addr |
1124 		~ netmask->sin_addr.s_addr;
1125 	error = ifioctl(so, SIOCSIFBRDADDR, (caddr_t) ireq, proc0.p_ucred);
1126 	if (error != 0)
1127 		panic("bootpc_adjust_interface: "
1128 		      "set if broadcast addr, error=%d", error);
1129 
1130 	bcopy(myaddr, &ireq->ifr_addr, sizeof(*myaddr));
1131 	error = ifioctl(so, SIOCSIFADDR, (caddr_t) ireq, proc0.p_ucred);
1132 	if (error != 0 && (error != EEXIST || ifctx == gctx->interfaces))
1133 		panic("bootpc_adjust_interface: "
1134 		      "set if addr, error=%d", error);
1135 
1136 	/* Add new default route */
1137 
1138 	if (ifctx->gotgw != 0 || gctx->gotgw == 0) {
1139 		clear_sinaddr(&defdst);
1140 		clear_sinaddr(&defmask);
1141 		error = rtrequest_global(RTM_ADD, (struct sockaddr *) &defdst,
1142 					 (struct sockaddr *) gw,
1143 					 (struct sockaddr *) &defmask,
1144 					 (RTF_UP | RTF_GATEWAY | RTF_STATIC));
1145 		if (error != 0) {
1146 			kprintf("bootpc_adjust_interface: "
1147 			       "add net route, error=%d\n", error);
1148 			return error;
1149 		}
1150 	}
1151 
1152 	return 0;
1153 }
1154 
1155 static void
1156 print_sin_addr(struct sockaddr_in *sin)
1157 {
1158 	print_in_addr(sin->sin_addr);
1159 }
1160 
1161 
1162 static void
1163 print_in_addr(struct in_addr addr)
1164 {
1165 	unsigned int ip;
1166 
1167 	ip = ntohl(addr.s_addr);
1168 	kprintf("%d.%d.%d.%d",
1169 	       ip >> 24, (ip >> 16) & 255, (ip >> 8) & 255, ip & 255);
1170 }
1171 
1172 static void
1173 bootpc_compose_query(struct bootpc_ifcontext *ifctx,
1174 		     struct bootpc_globalcontext *gctx, struct thread *td)
1175 {
1176 	unsigned char *vendp;
1177 	unsigned char vendor_client[64];
1178 	uint32_t leasetime;
1179 	uint8_t vendor_client_len;
1180 
1181 	ifctx->gotrootpath = 0;
1182 
1183 	bzero((caddr_t) &ifctx->call, sizeof(ifctx->call));
1184 
1185 	/* bootpc part */
1186 	ifctx->call.op = BOOTP_REQUEST; 	/* BOOTREQUEST */
1187 	ifctx->call.htype = 1;			/* 10mb ethernet */
1188 	ifctx->call.hlen = ifctx->sdl->sdl_alen;/* Hardware address length */
1189 	ifctx->call.hops = 0;
1190 	if (bootpc_ifctx_isunresolved(ifctx) != 0)
1191 		ifctx->xid++;
1192 	ifctx->call.xid = txdr_unsigned(ifctx->xid);
1193 	bcopy(LLADDR(ifctx->sdl), &ifctx->call.chaddr, ifctx->sdl->sdl_alen);
1194 
1195 	vendp = ifctx->call.vend;
1196 	*vendp++ = 99;		/* RFC1048 cookie */
1197 	*vendp++ = 130;
1198 	*vendp++ = 83;
1199 	*vendp++ = 99;
1200 	*vendp++ = TAG_MAXMSGSIZE;
1201 	*vendp++ = 2;
1202 	*vendp++ = (sizeof(struct bootp_packet) >> 8) & 255;
1203 	*vendp++ = sizeof(struct bootp_packet) & 255;
1204 
1205 	ksnprintf(vendor_client, sizeof(vendor_client), "%s:%s:%s",
1206 		ostype, MACHINE, osrelease);
1207 	vendor_client_len = strlen(vendor_client);
1208 	*vendp++ = TAG_VENDOR_INDENTIFIER;
1209 	*vendp++ = vendor_client_len;
1210 	memcpy(vendp, vendor_client, vendor_client_len);
1211 	vendp += vendor_client_len;
1212 	ifctx->dhcpquerytype = DHCP_NOMSG;
1213 	switch (ifctx->state) {
1214 	case IF_DHCP_UNRESOLVED:
1215 		*vendp++ = TAG_DHCP_MSGTYPE;
1216 		*vendp++ = 1;
1217 		*vendp++ = DHCP_DISCOVER;
1218 		ifctx->dhcpquerytype = DHCP_DISCOVER;
1219 		ifctx->gotdhcpserver = 0;
1220 		break;
1221 	case IF_DHCP_OFFERED:
1222 		*vendp++ = TAG_DHCP_MSGTYPE;
1223 		*vendp++ = 1;
1224 		*vendp++ = DHCP_REQUEST;
1225 		ifctx->dhcpquerytype = DHCP_REQUEST;
1226 		*vendp++ = TAG_DHCP_REQ_ADDR;
1227 		*vendp++ = 4;
1228 		memcpy(vendp, &ifctx->reply.yiaddr, 4);
1229 		vendp += 4;
1230 		if (ifctx->gotdhcpserver != 0) {
1231 			*vendp++ = TAG_DHCP_SERVERID;
1232 			*vendp++ = 4;
1233 			memcpy(vendp, &ifctx->dhcpserver, 4);
1234 			vendp += 4;
1235 		}
1236 		*vendp++ = TAG_DHCP_LEASETIME;
1237 		*vendp++ = 4;
1238 		leasetime = htonl(300);
1239 		memcpy(vendp, &leasetime, 4);
1240 		vendp += 4;
1241 	default:
1242 		;
1243 	}
1244 	*vendp = TAG_END;
1245 
1246 	ifctx->call.secs = 0;
1247 	ifctx->call.flags = htons(0x8000); /* We need an broadcast answer */
1248 }
1249 
1250 
1251 static int
1252 bootpc_hascookie(struct bootp_packet *bp)
1253 {
1254 	return (bp->vend[0] == 99 && bp->vend[1] == 130 &&
1255 		bp->vend[2] == 83 && bp->vend[3] == 99);
1256 }
1257 
1258 
1259 static void
1260 bootpc_tag_helper(struct bootpc_tagcontext *tctx,
1261 		  unsigned char *start, int len, int tag)
1262 {
1263 	unsigned char *j;
1264 	unsigned char *ej;
1265 	unsigned char code;
1266 
1267 	if (tctx->badtag != 0 || tctx->badopt != 0)
1268 		return;
1269 
1270 	j = start;
1271 	ej = j + len;
1272 
1273 	while (j < ej) {
1274 		code = *j++;
1275 		if (code == TAG_PAD)
1276 			continue;
1277 		if (code == TAG_END)
1278 			return;
1279 		if (j >= ej || j + *j + 1 > ej) {
1280 			tctx->badopt = 1;
1281 			return;
1282 		}
1283 		len = *j++;
1284 		if (code == tag) {
1285 			if (tctx->taglen + len > TAG_MAXLEN) {
1286 				tctx->badtag = 1;
1287 				return;
1288 			}
1289 			tctx->foundopt = 1;
1290 			if (len > 0)
1291 				memcpy(tctx->buf + tctx->taglen,
1292 				       j, len);
1293 			tctx->taglen += len;
1294 		}
1295 		if (code == TAG_OVERLOAD)
1296 			tctx->overload = *j;
1297 
1298 		j += len;
1299 	}
1300 }
1301 
1302 
1303 static unsigned char *
1304 bootpc_tag(struct bootpc_tagcontext *tctx, struct bootp_packet *bp,
1305 	   int len, int tag)
1306 {
1307 	tctx->overload = 0;
1308 	tctx->badopt = 0;
1309 	tctx->badtag = 0;
1310 	tctx->foundopt = 0;
1311 	tctx->taglen = 0;
1312 
1313 	if (bootpc_hascookie(bp) == 0)
1314 		return NULL;
1315 
1316 	bootpc_tag_helper(tctx, &bp->vend[4],
1317 			  (unsigned char *) bp + len - &bp->vend[4], tag);
1318 
1319 	if ((tctx->overload & OVERLOAD_FILE) != 0)
1320 		bootpc_tag_helper(tctx,
1321 				  (unsigned char *) bp->file,
1322 				  sizeof(bp->file),
1323 				  tag);
1324 	if ((tctx->overload & OVERLOAD_SNAME) != 0)
1325 		bootpc_tag_helper(tctx,
1326 				  (unsigned char *) bp->sname,
1327 				  sizeof(bp->sname),
1328 				  tag);
1329 
1330 	if (tctx->badopt != 0 || tctx->badtag != 0 || tctx->foundopt == 0)
1331 		return NULL;
1332 	tctx->buf[tctx->taglen] = '\0';
1333 	return tctx->buf;
1334 }
1335 
1336 
1337 static void
1338 bootpc_decode_reply(struct nfsv3_diskless *nd, struct bootpc_ifcontext *ifctx,
1339 		    struct bootpc_globalcontext *gctx)
1340 {
1341 	char *p;
1342 	unsigned int ip;
1343 
1344 	ifctx->gotgw = 0;
1345 	ifctx->gotnetmask = 0;
1346 
1347 	clear_sinaddr(&ifctx->myaddr);
1348 	clear_sinaddr(&ifctx->netmask);
1349 	clear_sinaddr(&ifctx->gw);
1350 
1351 	ifctx->myaddr.sin_addr = ifctx->reply.yiaddr;
1352 
1353 	ip = ntohl(ifctx->myaddr.sin_addr.s_addr);
1354 	ksnprintf(gctx->lookup_path, sizeof(gctx->lookup_path),
1355 		 "swap.%d.%d.%d.%d",
1356 		 ip >> 24, (ip >> 16) & 255, (ip >> 8) & 255, ip & 255);
1357 
1358 	kprintf("%s at ", ifctx->ireq.ifr_name);
1359 	print_sin_addr(&ifctx->myaddr);
1360 	kprintf(" server ");
1361 	print_in_addr(ifctx->reply.siaddr);
1362 
1363 	ifctx->gw.sin_addr = ifctx->reply.giaddr;
1364 	if (ifctx->reply.giaddr.s_addr != htonl(INADDR_ANY)) {
1365 		kprintf(" via gateway ");
1366 		print_in_addr(ifctx->reply.giaddr);
1367 	}
1368 
1369 	/* This call used for the side effect (overload flag) */
1370 	(void) bootpc_tag(&gctx->tmptag,
1371 			  &ifctx->reply, ifctx->replylen, TAG_END);
1372 
1373 	if ((gctx->tmptag.overload & OVERLOAD_SNAME) == 0)
1374 		if (ifctx->reply.sname[0] != '\0')
1375 			kprintf(" server name %s", ifctx->reply.sname);
1376 	if ((gctx->tmptag.overload & OVERLOAD_FILE) == 0)
1377 		if (ifctx->reply.file[0] != '\0')
1378 			kprintf(" boot file %s", ifctx->reply.file);
1379 
1380 	kprintf("\n");
1381 
1382 	p = bootpc_tag(&gctx->tag, &ifctx->reply, ifctx->replylen,
1383 		       TAG_SUBNETMASK);
1384 	if (p != NULL) {
1385 		if (gctx->tag.taglen != 4)
1386 			panic("bootpc: subnet mask len is %d",
1387 			      gctx->tag.taglen);
1388 		bcopy(p, &ifctx->netmask.sin_addr, 4);
1389 		ifctx->gotnetmask = 1;
1390 		kprintf("subnet mask ");
1391 		print_sin_addr(&ifctx->netmask);
1392 		kprintf(" ");
1393 	}
1394 
1395 	p = bootpc_tag(&gctx->tag, &ifctx->reply, ifctx->replylen,
1396 		       TAG_ROUTERS);
1397 	if (p != NULL) {
1398 		/* Routers */
1399 		if (gctx->tag.taglen % 4)
1400 			panic("bootpc: Router Len is %d", gctx->tag.taglen);
1401 		if (gctx->tag.taglen > 0) {
1402 			bcopy(p, &ifctx->gw.sin_addr, 4);
1403 			kprintf("router ");
1404 			print_sin_addr(&ifctx->gw);
1405 			kprintf(" ");
1406 			ifctx->gotgw = 1;
1407 			gctx->gotgw = 1;
1408 		}
1409 	}
1410 
1411 	p = bootpc_tag(&gctx->tag, &ifctx->reply, ifctx->replylen,
1412 		       TAG_ROOT);
1413 	if (p != NULL) {
1414 		if (gctx->setrootfs != NULL) {
1415 			kprintf("rootfs %s (ignored) ", p);
1416 		} else 	if (setfs(&nd->root_saddr,
1417 				  nd->root_hostnam, p)) {
1418 			kprintf("rootfs %s ",p);
1419 			gctx->gotrootpath = 1;
1420 			ifctx->gotrootpath = 1;
1421 			gctx->setrootfs = ifctx;
1422 
1423 			p = bootpc_tag(&gctx->tag, &ifctx->reply,
1424 				       ifctx->replylen,
1425 				       TAG_ROOTOPTS);
1426 			if (p != NULL) {
1427 				nfs_mountopts(&nd->root_args, p);
1428 				kprintf("rootopts %s ", p);
1429 			}
1430 		} else
1431 			panic("Failed to set rootfs to %s",p);
1432 	}
1433 
1434 	p = bootpc_tag(&gctx->tag, &ifctx->reply, ifctx->replylen,
1435 		       TAG_SWAP);
1436 	if (p != NULL) {
1437 		if (gctx->setswapfs != NULL) {
1438 			kprintf("swapfs %s (ignored) ", p);
1439 		} else 	if (setfs(&nd->swap_saddr,
1440 				  nd->swap_hostnam, p)) {
1441 			gctx->gotswappath = 1;
1442 			gctx->setswapfs = ifctx;
1443 			kprintf("swapfs %s ", p);
1444 
1445 			p = bootpc_tag(&gctx->tag, &ifctx->reply,
1446 				       ifctx->replylen,
1447 				       TAG_SWAPOPTS);
1448 			if (p != NULL) {
1449 				/* swap mount options */
1450 				nfs_mountopts(&nd->swap_args, p);
1451 				kprintf("swapopts %s ", p);
1452 			}
1453 
1454 			p = bootpc_tag(&gctx->tag, &ifctx->reply,
1455 				       ifctx->replylen,
1456 				       TAG_SWAPSIZE);
1457 			if (p != NULL) {
1458 				int swaplen;
1459 				if (gctx->tag.taglen != 4)
1460 					panic("bootpc: "
1461 					      "Expected 4 bytes for swaplen, "
1462 					      "not %d bytes",
1463 					      gctx->tag.taglen);
1464 				bcopy(p, &swaplen, 4);
1465 				nd->swap_nblks = ntohl(swaplen);
1466 				kprintf("swapsize %d KB ",
1467 				       nd->swap_nblks);
1468 			}
1469 		} else
1470 			panic("Failed to set swapfs to %s", p);
1471 	}
1472 
1473 	p = bootpc_tag(&gctx->tag, &ifctx->reply, ifctx->replylen,
1474 		       TAG_HOSTNAME);
1475 	if (p != NULL) {
1476 		if (gctx->tag.taglen >= MAXHOSTNAMELEN)
1477 			panic("bootpc: hostname >= %d bytes",
1478 			      MAXHOSTNAMELEN);
1479 		if (gctx->sethostname != NULL) {
1480 			kprintf("hostname %s (ignored) ", p);
1481 		} else {
1482 			strcpy(nd->my_hostnam, p);
1483 			strcpy(hostname, p);
1484 			kprintf("hostname %s ",hostname);
1485 			gctx->sethostname = ifctx;
1486 		}
1487 	}
1488 	p = bootpc_tag(&gctx->tag, &ifctx->reply, ifctx->replylen,
1489 		       TAG_COOKIE);
1490 	if (p != NULL) {	/* store in a sysctl variable */
1491 		int i, l = sizeof(bootp_cookie) - 1;
1492 		for (i = 0; i < l && p[i] != '\0'; i++)
1493 			bootp_cookie[i] = p[i];
1494 		p[i] = '\0';
1495 	}
1496 
1497 	kprintf("\n");
1498 
1499 	if (ifctx->gotnetmask == 0) {
1500 		if (IN_CLASSA(ntohl(ifctx->myaddr.sin_addr.s_addr)))
1501 			ifctx->netmask.sin_addr.s_addr = htonl(IN_CLASSA_NET);
1502 		else if (IN_CLASSB(ntohl(ifctx->myaddr.sin_addr.s_addr)))
1503 			ifctx->netmask.sin_addr.s_addr = htonl(IN_CLASSB_NET);
1504 		else
1505 			ifctx->netmask.sin_addr.s_addr = htonl(IN_CLASSC_NET);
1506 	}
1507 	if (ifctx->gotgw == 0) {
1508 		/* Use proxyarp */
1509 		ifctx->gw.sin_addr.s_addr = ifctx->myaddr.sin_addr.s_addr;
1510 	}
1511 }
1512 
1513 void
1514 bootpc_init(void)
1515 {
1516 	struct bootpc_ifcontext *ifctx, *nctx;	/* Interface BOOTP contexts */
1517 	struct bootpc_globalcontext *gctx; 	/* Global BOOTP context */
1518 	struct ifnet *ifp;
1519 	int error;
1520 	struct nfsv3_diskless *nd;
1521 	struct thread *td;
1522 
1523 	nd = &nfsv3_diskless;
1524 	td = curthread;
1525 
1526 	/*
1527 	 * If already filled in, don't touch it here
1528 	 */
1529 	if (nfs_diskless_valid != 0)
1530 		return;
1531 
1532 	/*
1533 	 * Wait until arp entries can be handled.
1534 	 */
1535 	while (time_second == 0)
1536 		tsleep(&time_second, 0, "arpkludge", 10);
1537 
1538 	gctx = kmalloc(sizeof(*gctx), M_TEMP, M_WAITOK | M_ZERO);
1539 
1540 	gctx->xid = ~0xFFFF;
1541 	gctx->starttime = time_second;
1542 
1543 	ifctx = allocifctx(gctx);
1544 
1545 	/*
1546 	 * Find a network interface.
1547 	 */
1548 #ifdef BOOTP_WIRED_TO
1549 	kprintf("bootpc_init: wired to interface '%s'\n",
1550 	       __XSTRING(BOOTP_WIRED_TO));
1551 #endif
1552 	bzero(&ifctx->ireq, sizeof(ifctx->ireq));
1553 	TAILQ_FOREACH(ifp, &ifnet, if_link) {
1554 		strlcpy(ifctx->ireq.ifr_name, ifp->if_xname,
1555 			 sizeof(ifctx->ireq.ifr_name));
1556 #ifdef BOOTP_WIRED_TO
1557 		if (strcmp(ifctx->ireq.ifr_name,
1558 			   __XSTRING(BOOTP_WIRED_TO)) != 0)
1559 			continue;
1560 #else
1561 		if ((ifp->if_flags &
1562 		     (IFF_LOOPBACK | IFF_POINTOPOINT | IFF_BROADCAST)) !=
1563 		    IFF_BROADCAST)
1564 			continue;
1565 #endif
1566 		if (gctx->interfaces != NULL)
1567 			gctx->lastinterface->next = ifctx;
1568 		else
1569 			gctx->interfaces = ifctx;
1570 		ifctx->ifp = ifp;
1571 		gctx->lastinterface = ifctx;
1572 		ifctx = allocifctx(gctx);
1573 	}
1574 	kfree(ifctx, M_TEMP);
1575 
1576 	if (gctx->interfaces == NULL) {
1577 #ifdef BOOTP_WIRED_TO
1578 		panic("bootpc_init: Could not find interface specified "
1579 		      "by BOOTP_WIRED_TO: "
1580 		      __XSTRING(BOOTP_WIRED_TO));
1581 #else
1582 		panic("bootpc_init: no suitable interface");
1583 #endif
1584 	}
1585 
1586 	gctx->gotrootpath = 0;
1587 	gctx->gotswappath = 0;
1588 	gctx->gotgw = 0;
1589 
1590 	for (ifctx = gctx->interfaces; ifctx != NULL; ifctx = ifctx->next)
1591 		bootpc_fakeup_interface(ifctx, gctx, td);
1592 
1593 	for (ifctx = gctx->interfaces; ifctx != NULL; ifctx = ifctx->next)
1594 		bootpc_compose_query(ifctx, gctx, td);
1595 
1596 	ifctx = gctx->interfaces;
1597 	error = bootpc_call(gctx, td);
1598 
1599 	if (error != 0) {
1600 #ifdef BOOTP_NFSROOT
1601 		panic("BOOTP call failed");
1602 #else
1603 		kprintf("BOOTP call failed\n");
1604 #endif
1605 	}
1606 
1607 	nfs_mountopts(&nd->root_args, NULL);
1608 
1609 	nfs_mountopts(&nd->swap_args, NULL);
1610 
1611 	for (ifctx = gctx->interfaces; ifctx != NULL; ifctx = ifctx->next)
1612 		if (bootpc_ifctx_isresolved(ifctx) != 0)
1613 			bootpc_decode_reply(nd, ifctx, gctx);
1614 
1615 	if (gctx->gotswappath == 0)
1616 		nd->swap_nblks = 0;
1617 #ifdef BOOTP_NFSROOT
1618 	if (gctx->gotrootpath == 0)
1619 		panic("bootpc: No root path offered");
1620 #endif
1621 
1622 	for (ifctx = gctx->interfaces; ifctx != NULL; ifctx = ifctx->next) {
1623 		bootpc_adjust_interface(ifctx, gctx, td);
1624 
1625 		soclose(ifctx->so, FNONBLOCK);
1626 	}
1627 
1628 	for (ifctx = gctx->interfaces; ifctx != NULL; ifctx = ifctx->next)
1629 		if (ifctx->gotrootpath != 0)
1630 			break;
1631 	if (ifctx == NULL) {
1632 		for (ifctx = gctx->interfaces;
1633 		     ifctx != NULL;
1634 		     ifctx = ifctx->next)
1635 			if (bootpc_ifctx_isresolved(ifctx) != 0)
1636 				break;
1637 	}
1638 	if (ifctx == NULL)
1639 		goto out;
1640 
1641 	if (gctx->gotrootpath != 0) {
1642 
1643 		error = md_mount(&nd->root_saddr, nd->root_hostnam,
1644 				 nd->root_fh, &nd->root_fhsize,
1645 				 &nd->root_args, td);
1646 		if (error != 0)
1647 			panic("nfs_boot: mountd root, error=%d", error);
1648 
1649 		if (gctx->gotswappath != 0) {
1650 
1651 			error = md_mount(&nd->swap_saddr,
1652 					 nd->swap_hostnam,
1653 					 nd->swap_fh, &nd->swap_fhsize,
1654 					 &nd->swap_args, td);
1655 			if (error != 0)
1656 				panic("nfs_boot: mountd swap, error=%d",
1657 				      error);
1658 
1659 			error = md_lookup_swap(&nd->swap_saddr,
1660 					       gctx->lookup_path,
1661 					       nd->swap_fh, &nd->swap_fhsize,
1662 					       &nd->swap_args, td);
1663 			if (error != 0)
1664 				panic("nfs_boot: lookup swap, error=%d",
1665 				      error);
1666 		}
1667 		nfs_diskless_valid = 3;
1668 	}
1669 
1670 	strcpy(nd->myif.ifra_name, ifctx->ireq.ifr_name);
1671 	bcopy(&ifctx->myaddr, &nd->myif.ifra_addr, sizeof(ifctx->myaddr));
1672 	bcopy(&ifctx->myaddr, &nd->myif.ifra_broadaddr, sizeof(ifctx->myaddr));
1673 	((struct sockaddr_in *) &nd->myif.ifra_broadaddr)->sin_addr.s_addr =
1674 		ifctx->myaddr.sin_addr.s_addr |
1675 		~ ifctx->netmask.sin_addr.s_addr;
1676 	bcopy(&ifctx->netmask, &nd->myif.ifra_mask, sizeof(ifctx->netmask));
1677 
1678 out:
1679 	for (ifctx = gctx->interfaces; ifctx != NULL; ifctx = nctx) {
1680 		nctx = ifctx->next;
1681 		kfree(ifctx, M_TEMP);
1682 	}
1683 	kfree(gctx, M_TEMP);
1684 }
1685 
1686