xref: /dflybsd-src/sys/vfs/nfs/bootp_subr.c (revision 978400d3b04daf8f91ba8bb2dcc382a37ef632f4)
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  * $DragonFly: src/sys/vfs/nfs/bootp_subr.c,v 1.24 2008/01/06 16:55:53 swildner Exp $
42  */
43 
44 #include "opt_bootp.h"
45 
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/kernel.h>
49 #include <sys/sockio.h>
50 #include <sys/proc.h>
51 #include <sys/malloc.h>
52 #include <sys/mount.h>
53 #include <sys/mbuf.h>
54 #include <sys/socket.h>
55 #include <sys/socketvar.h>
56 #include <sys/sysctl.h>
57 #include <sys/uio.h>
58 #include <sys/fcntl.h>
59 
60 #include <net/if.h>
61 #include <net/route.h>
62 
63 #include <netinet/in.h>
64 #include <net/if_types.h>
65 #include <net/if_dl.h>
66 
67 #include "rpcv2.h"
68 #include "nfsproto.h"
69 #include "nfs.h"
70 #include "nfsdiskless.h"
71 #include "krpc.h"
72 #include "xdr_subs.h"
73 #include "nfsmountrpc.h"
74 
75 #define BOOTP_MIN_LEN		300	/* Minimum size of bootp udp packet */
76 
77 #ifndef BOOTP_SETTLE_DELAY
78 #define BOOTP_SETTLE_DELAY 3
79 #endif
80 
81 /*
82  * What is the longest we will wait before re-sending a request?
83  * Note this is also the frequency of "RPC timeout" messages.
84  * The re-send loop count sup linearly to this maximum, so the
85  * first complaint will happen after (1+2+3+4+5)=15 seconds.
86  */
87 #define	MAX_RESEND_DELAY 5	/* seconds */
88 
89 /* Definitions from RFC951 */
90 struct bootp_packet {
91 	u_int8_t op;
92 	u_int8_t htype;
93 	u_int8_t hlen;
94 	u_int8_t hops;
95 	u_int32_t xid;
96 	u_int16_t secs;
97 	u_int16_t flags;
98 	struct in_addr ciaddr;
99 	struct in_addr yiaddr;
100 	struct in_addr siaddr;
101 	struct in_addr giaddr;
102 	unsigned char chaddr[16];
103 	char sname[64];
104 	char file[128];
105 	unsigned char vend[1222];
106 };
107 
108 struct bootpc_ifcontext {
109 	struct bootpc_ifcontext *next;
110 	struct bootp_packet call;
111 	struct bootp_packet reply;
112 	int replylen;
113 	int overload;
114 	struct socket *so;
115 	struct ifreq ireq;
116 	struct ifnet *ifp;
117 	struct sockaddr_dl *sdl;
118 	struct sockaddr_in myaddr;
119 	struct sockaddr_in netmask;
120 	struct sockaddr_in gw;
121 	struct sockaddr_in broadcast;	/* Different for each interface */
122 	int gotgw;
123 	int gotnetmask;
124 	int gotrootpath;
125 	int outstanding;
126 	int sentmsg;
127 	u_int32_t xid;
128 	enum {
129 		IF_BOOTP_UNRESOLVED,
130 		IF_BOOTP_RESOLVED,
131 		IF_BOOTP_FAILED,
132 		IF_DHCP_UNRESOLVED,
133 		IF_DHCP_OFFERED,
134 		IF_DHCP_RESOLVED,
135 		IF_DHCP_FAILED,
136 	} state;
137 	int dhcpquerytype;		/* dhcp type sent */
138 	struct in_addr dhcpserver;
139 	int gotdhcpserver;
140 };
141 
142 #define TAG_MAXLEN 1024
143 struct bootpc_tagcontext {
144 	char buf[TAG_MAXLEN + 1];
145 	int overload;
146 	int badopt;
147 	int badtag;
148 	int foundopt;
149 	int taglen;
150 };
151 
152 struct bootpc_globalcontext {
153 	struct bootpc_ifcontext *interfaces;
154 	struct bootpc_ifcontext *lastinterface;
155 	u_int32_t xid;
156 	int gotrootpath;
157 	int gotswappath;
158 	int gotgw;
159 	int ifnum;
160 	int secs;
161 	int starttime;
162 	struct bootp_packet reply;
163 	int replylen;
164 	struct bootpc_ifcontext *setswapfs;
165 	struct bootpc_ifcontext *setrootfs;
166 	struct bootpc_ifcontext *sethostname;
167 	char lookup_path[24];
168 	struct bootpc_tagcontext tmptag;
169 	struct bootpc_tagcontext tag;
170 };
171 
172 #define IPPORT_BOOTPC 68
173 #define IPPORT_BOOTPS 67
174 
175 #define BOOTP_REQUEST 1
176 #define BOOTP_REPLY 2
177 
178 /* Common tags */
179 #define TAG_PAD		  0  /* Pad option, implicit length 1 */
180 #define TAG_SUBNETMASK	  1  /* RFC 950 subnet mask */
181 #define TAG_ROUTERS	  3  /* Routers (in order of preference) */
182 #define TAG_HOSTNAME	 12  /* Client host name */
183 #define TAG_ROOT	 17  /* Root path */
184 
185 /* DHCP specific tags */
186 #define TAG_OVERLOAD	 52  /* Option Overload */
187 #define TAG_MAXMSGSIZE   57  /* Maximum DHCP Message Size */
188 
189 #define TAG_END		255  /* End Option (i.e. no more options) */
190 
191 /* Overload values */
192 #define OVERLOAD_FILE     1
193 #define OVERLOAD_SNAME    2
194 
195 /* Site specific tags: */
196 #define TAG_SWAP	128
197 #define TAG_SWAPSIZE	129
198 #define TAG_ROOTOPTS	130
199 #define TAG_SWAPOPTS	131
200 #define TAG_COOKIE	134	/* ascii info for userland, exported via sysctl */
201 
202 #define TAG_DHCP_MSGTYPE 53
203 #define TAG_DHCP_REQ_ADDR 50
204 #define TAG_DHCP_SERVERID 54
205 #define TAG_DHCP_LEASETIME 51
206 
207 #define TAG_VENDOR_INDENTIFIER 60
208 
209 #define DHCP_NOMSG    0
210 #define DHCP_DISCOVER 1
211 #define DHCP_OFFER    2
212 #define DHCP_REQUEST  3
213 #define DHCP_ACK      5
214 
215 extern struct nfsv3_diskless nfsv3_diskless;
216 static char bootp_cookie[128];
217 SYSCTL_STRING(_kern, OID_AUTO, bootp_cookie, CTLFLAG_RD,
218 	bootp_cookie, 0, "Cookie (T134) supplied by bootp server");
219 
220 /* mountd RPC */
221 static void print_in_addr(struct in_addr addr);
222 static void print_sin_addr(struct sockaddr_in *addr);
223 static void clear_sinaddr(struct sockaddr_in *sin);
224 static
225 struct bootpc_ifcontext *allocifctx(struct bootpc_globalcontext *gctx);
226 static void bootpc_compose_query(struct bootpc_ifcontext *ifctx,
227 				 struct bootpc_globalcontext *gctx,
228 				 struct thread *td);
229 static unsigned char *bootpc_tag(struct bootpc_tagcontext *tctx,
230 				 struct bootp_packet *bp, int len, int tag);
231 static void bootpc_tag_helper(struct bootpc_tagcontext *tctx,
232 			      unsigned char *start, int len, int tag);
233 
234 #ifdef BOOTP_DEBUG
235 void bootpboot_p_sa(struct sockaddr *sa,struct sockaddr *ma);
236 void bootpboot_p_ma(struct sockaddr *ma);
237 void bootpboot_p_rtentry(struct rtentry *rt);
238 void bootpboot_p_tree(struct radix_node *rn);
239 void bootpboot_p_rtlist(void);
240 void bootpboot_p_if(struct ifnet *ifp, struct ifaddr *ifa);
241 void bootpboot_p_iflist(void);
242 #endif
243 
244 static int  bootpc_call(struct bootpc_globalcontext *gctx,
245 			struct thread *td);
246 
247 static int bootpc_fakeup_interface(struct bootpc_ifcontext *ifctx,
248 				   struct bootpc_globalcontext *gctx,
249 				   struct thread *td);
250 
251 static int bootpc_adjust_interface(struct bootpc_ifcontext *ifctx,
252 				   struct bootpc_globalcontext *gctx,
253 				   struct thread *td);
254 
255 static void bootpc_decode_reply(struct nfsv3_diskless *nd,
256 				struct bootpc_ifcontext *ifctx,
257 				struct bootpc_globalcontext *gctx);
258 
259 static int bootpc_received(struct bootpc_globalcontext *gctx,
260 			   struct bootpc_ifcontext *ifctx);
261 
262 static __inline int bootpc_ifctx_isresolved(struct bootpc_ifcontext *ifctx);
263 static __inline int bootpc_ifctx_isunresolved(struct bootpc_ifcontext *ifctx);
264 static __inline int bootpc_ifctx_isfailed(struct bootpc_ifcontext *ifctx);
265 
266 void bootpc_init(void);
267 
268 /*
269  * In order to have multiple active interfaces with address 0.0.0.0
270  * and be able to send data to a selected interface, we perform
271  * some tricks:
272  *
273  *  - The 'broadcast' address is different for each interface.
274  *
275  *  - We temporarily add routing pointing 255.255.255.255 to the
276  *    selected interface broadcast address, thus the packet sent
277  *    goes to that interface.
278  */
279 
280 #ifdef BOOTP_DEBUG
281 void
282 bootpboot_p_sa(struct sockaddr *sa, struct sockaddr *ma)
283 {
284 	if (sa == NULL) {
285 		kprintf("(sockaddr *) <null>");
286 		return;
287 	}
288 	switch (sa->sa_family) {
289 	case AF_INET:
290 	{
291 		struct sockaddr_in *sin;
292 
293 		sin = (struct sockaddr_in *) sa;
294 		kprintf("inet ");
295 		print_sin_addr(sin);
296 		if (ma != NULL) {
297 			sin = (struct sockaddr_in *) ma;
298 			kprintf(" mask ");
299 			print_sin_addr(sin);
300 		}
301 	}
302 	break;
303 	case AF_LINK:
304 	{
305 		struct sockaddr_dl *sli;
306 		int i;
307 
308 		sli = (struct sockaddr_dl *) sa;
309 		kprintf("link %.*s ", sli->sdl_nlen, sli->sdl_data);
310 		for (i = 0; i < sli->sdl_alen; i++) {
311 			if (i > 0)
312 				kprintf(":");
313 			kprintf("%x", ((unsigned char *) LLADDR(sli))[i]);
314 		}
315 	}
316 	break;
317 	default:
318 		kprintf("af%d", sa->sa_family);
319 	}
320 }
321 
322 
323 void
324 bootpboot_p_ma(struct sockaddr *ma)
325 {
326 	if (ma == NULL) {
327 		kprintf("<null>");
328 		return;
329 	}
330 	kprintf("%x", *(int *)ma);
331 }
332 
333 
334 void
335 bootpboot_p_rtentry(struct rtentry *rt)
336 {
337 	bootpboot_p_sa(rt_key(rt), rt_mask(rt));
338 	kprintf(" ");
339 	bootpboot_p_ma(rt->rt_genmask);
340 	kprintf(" ");
341 	bootpboot_p_sa(rt->rt_gateway, NULL);
342 	kprintf(" ");
343 	kprintf("flags %x", (unsigned short) rt->rt_flags);
344 	kprintf(" %d", (int) rt->rt_rmx.rmx_expire);
345 	kprintf(" %s\n", if_name(rt->rt_ifp));
346 }
347 
348 
349 void
350 bootpboot_p_tree(struct radix_node *rn)
351 {
352 	while (rn != NULL) {
353 		if (rn->rn_bit < 0) {
354 			if ((rn->rn_flags & RNF_ROOT) != 0) {
355 			} else {
356 				bootpboot_p_rtentry((struct rtentry *) rn);
357 			}
358 			rn = rn->rn_dupedkey;
359 		} else {
360 			bootpboot_p_tree(rn->rn_left);
361 			bootpboot_p_tree(rn->rn_right);
362 			return;
363 		}
364 	}
365 }
366 
367 
368 void
369 bootpboot_p_rtlist(void)
370 {
371 	kprintf("Routing table:\n");
372 	bootpboot_p_tree(rt_tables[AF_INET]->rnh_treetop);
373 }
374 
375 
376 void
377 bootpboot_p_if(struct ifnet *ifp, struct ifaddr *ifa)
378 {
379 	kprintf("%s flags %x, addr ",
380 	       if_name(ifp),
381 	       (unsigned short) ifp->if_flags);
382 	print_sin_addr((struct sockaddr_in *) ifa->ifa_addr);
383 	kprintf(", broadcast ");
384 	print_sin_addr((struct sockaddr_in *) ifa->ifa_dstaddr);
385 	kprintf(", netmask ");
386 	print_sin_addr((struct sockaddr_in *) ifa->ifa_netmask);
387 	kprintf("\n");
388 }
389 
390 
391 void
392 bootpboot_p_iflist(void)
393 {
394 	struct ifnet *ifp;
395 	struct ifaddr *ifa;
396 
397 	kprintf("Interface list:\n");
398 	TAILQ_FOREACH(ifp, &ifnet, if_link) {
399 		TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link)
400 			if (ifa->ifa_addr->sa_family == AF_INET)
401 				bootpboot_p_if(ifp, ifa);
402 	}
403 }
404 #endif /* defined(BOOTP_DEBUG) */
405 
406 
407 static void
408 clear_sinaddr(struct sockaddr_in *sin)
409 {
410 	bzero(sin, sizeof(*sin));
411 	sin->sin_len = sizeof(*sin);
412 	sin->sin_family = AF_INET;
413 	sin->sin_addr.s_addr = INADDR_ANY; /* XXX: htonl(INAADDR_ANY) ? */
414 	sin->sin_port = 0;
415 }
416 
417 
418 static struct bootpc_ifcontext *
419 allocifctx(struct bootpc_globalcontext *gctx)
420 {
421 	struct bootpc_ifcontext *ifctx;
422 	ifctx = (struct bootpc_ifcontext *) kmalloc(sizeof(*ifctx),
423 						   M_TEMP, M_WAITOK);
424 	bzero(ifctx, sizeof(*ifctx));
425 	ifctx->xid = gctx->xid;
426 #ifdef BOOTP_NO_DHCP
427 	ifctx->state = IF_BOOTP_UNRESOLVED;
428 #else
429 	ifctx->state = IF_DHCP_UNRESOLVED;
430 #endif
431 	gctx->xid += 0x100;
432 	return ifctx;
433 }
434 
435 
436 static __inline int
437 bootpc_ifctx_isresolved(struct bootpc_ifcontext *ifctx)
438 {
439 	if (ifctx->state == IF_BOOTP_RESOLVED ||
440 	    ifctx->state == IF_DHCP_RESOLVED)
441 		return 1;
442 	return 0;
443 }
444 
445 
446 static __inline int
447 bootpc_ifctx_isunresolved(struct bootpc_ifcontext *ifctx)
448 {
449 	if (ifctx->state == IF_BOOTP_UNRESOLVED ||
450 	    ifctx->state == IF_DHCP_UNRESOLVED)
451 		return 1;
452 	return 0;
453 }
454 
455 
456 static __inline int
457 bootpc_ifctx_isfailed(struct bootpc_ifcontext *ifctx)
458 {
459 	if (ifctx->state == IF_BOOTP_FAILED ||
460 	    ifctx->state == IF_DHCP_FAILED)
461 		return 1;
462 	return 0;
463 }
464 
465 
466 static int
467 bootpc_received(struct bootpc_globalcontext *gctx,
468 		struct bootpc_ifcontext *ifctx)
469 {
470 	unsigned char dhcpreplytype;
471 	char *p;
472 	/*
473 	 * Need timeout for fallback to less
474 	 * desirable alternative.
475 	 */
476 
477 
478 	/* This call used for the side effect (badopt flag) */
479 	(void) bootpc_tag(&gctx->tmptag, &gctx->reply,
480 			  gctx->replylen,
481 			  TAG_END);
482 
483 	/* If packet is invalid, ignore it */
484 	if (gctx->tmptag.badopt != 0)
485 		return 0;
486 
487 	p = bootpc_tag(&gctx->tmptag, &gctx->reply,
488 		       gctx->replylen, TAG_DHCP_MSGTYPE);
489 	if (p != NULL)
490 		dhcpreplytype = *p;
491 	else
492 		dhcpreplytype = DHCP_NOMSG;
493 
494 	switch (ifctx->dhcpquerytype) {
495 	case DHCP_DISCOVER:
496 		if (dhcpreplytype != DHCP_OFFER 	/* Normal DHCP offer */
497 #ifndef BOOTP_FORCE_DHCP
498 		    && dhcpreplytype != DHCP_NOMSG	/* Fallback to BOOTP */
499 #endif
500 			)
501 			return 0;
502 		break;
503 	case DHCP_REQUEST:
504 		if (dhcpreplytype != DHCP_ACK)
505 			return 0;
506 		/* fall through */
507 	case DHCP_NOMSG:
508 		break;
509 	}
510 
511 
512 	/* Ignore packet unless it gives us a root tag we didn't have */
513 
514 	if ((ifctx->state == IF_BOOTP_RESOLVED ||
515 	     (ifctx->dhcpquerytype == DHCP_DISCOVER &&
516 	      (ifctx->state == IF_DHCP_OFFERED ||
517 	       ifctx->state == IF_DHCP_RESOLVED))) &&
518 	    (bootpc_tag(&gctx->tmptag, &ifctx->reply,
519 			ifctx->replylen,
520 			TAG_ROOT) != NULL ||
521 	     bootpc_tag(&gctx->tmptag, &gctx->reply,
522 			gctx->replylen,
523 			TAG_ROOT) == NULL))
524 		return 0;
525 
526 	bcopy(&gctx->reply,
527 	      &ifctx->reply,
528 	      gctx->replylen);
529 	ifctx->replylen = gctx->replylen;
530 
531 	/* XXX: Only reset if 'perfect' response */
532 	if (ifctx->state == IF_BOOTP_UNRESOLVED)
533 		ifctx->state = IF_BOOTP_RESOLVED;
534 	else if (ifctx->state == IF_DHCP_UNRESOLVED &&
535 		 ifctx->dhcpquerytype == DHCP_DISCOVER) {
536 		if (dhcpreplytype == DHCP_OFFER)
537 			ifctx->state = IF_DHCP_OFFERED;
538 		else
539 			ifctx->state = IF_BOOTP_RESOLVED;	/* Fallback */
540 	} else if (ifctx->state == IF_DHCP_OFFERED &&
541 		   ifctx->dhcpquerytype == DHCP_REQUEST)
542 		ifctx->state = IF_DHCP_RESOLVED;
543 
544 
545 	if (ifctx->dhcpquerytype == DHCP_DISCOVER &&
546 	    ifctx->state != IF_BOOTP_RESOLVED) {
547 		p = bootpc_tag(&gctx->tmptag, &ifctx->reply,
548 			       ifctx->replylen, TAG_DHCP_SERVERID);
549 		if (p != NULL && gctx->tmptag.taglen == 4) {
550 			memcpy(&ifctx->dhcpserver, p, 4);
551 			ifctx->gotdhcpserver = 1;
552 		} else
553 			ifctx->gotdhcpserver = 0;
554 		return 1;
555 	}
556 
557 	ifctx->gotrootpath = (bootpc_tag(&gctx->tmptag, &ifctx->reply,
558 					 ifctx->replylen,
559 					 TAG_ROOT) != NULL);
560 	ifctx->gotgw = (bootpc_tag(&gctx->tmptag, &ifctx->reply,
561 				   ifctx->replylen,
562 				   TAG_ROUTERS) != NULL);
563 	ifctx->gotnetmask = (bootpc_tag(&gctx->tmptag, &ifctx->reply,
564 					ifctx->replylen,
565 					TAG_SUBNETMASK) != NULL);
566 	return 1;
567 }
568 
569 static int
570 bootpc_call(struct bootpc_globalcontext *gctx, struct thread *td)
571 {
572 	struct socket *so;
573 	struct sockaddr_in *sin, dst;
574 	struct uio auio;
575 	struct sockopt sopt;
576 	struct iovec aio;
577 	int error, on, rcvflg, timo, len;
578 	time_t atimo;
579 	time_t rtimo;
580 	struct timeval tv;
581 	struct bootpc_ifcontext *ifctx;
582 	int outstanding;
583 	int gotrootpath;
584 	int retry;
585 	const char *s;
586 
587 	/*
588 	 * Create socket and set its recieve timeout.
589 	 */
590 	error = socreate(AF_INET, &so, SOCK_DGRAM, 0, td);
591 	if (error != 0)
592 		goto out;
593 
594 	tv.tv_sec = 1;
595 	tv.tv_usec = 0;
596 	bzero(&sopt, sizeof(sopt));
597 	sopt.sopt_level = SOL_SOCKET;
598 	sopt.sopt_name = SO_RCVTIMEO;
599 	sopt.sopt_val = &tv;
600 	sopt.sopt_valsize = sizeof tv;
601 
602 	error = sosetopt(so, &sopt);
603 	if (error != 0)
604 		goto out;
605 
606 	/*
607 	 * Enable broadcast.
608 	 */
609 	on = 1;
610 	sopt.sopt_name = SO_BROADCAST;
611 	sopt.sopt_val = &on;
612 	sopt.sopt_valsize = sizeof on;
613 
614 	error = sosetopt(so, &sopt);
615 	if (error != 0)
616 		goto out;
617 
618 	/*
619 	 * Disable routing.
620 	 */
621 
622 	on = 1;
623 	sopt.sopt_name = SO_DONTROUTE;
624 	sopt.sopt_val = &on;
625 	sopt.sopt_valsize = sizeof on;
626 
627 	error = sosetopt(so, &sopt);
628 	if (error != 0)
629 		goto out;
630 
631 	/*
632 	 * Bind the local endpoint to a bootp client port.
633 	 */
634 	sin = &dst;
635 	clear_sinaddr(sin);
636 	sin->sin_port = htons(IPPORT_BOOTPC);
637 	error = sobind(so, (struct sockaddr *)sin, td);
638 	if (error != 0) {
639 		kprintf("bind failed\n");
640 		goto out;
641 	}
642 
643 	/*
644 	 * Setup socket address for the server.
645 	 */
646 	sin = &dst;
647 	clear_sinaddr(sin);
648 	sin->sin_addr.s_addr = INADDR_BROADCAST;
649 	sin->sin_port = htons(IPPORT_BOOTPS);
650 
651 	/*
652 	 * Send it, repeatedly, until a reply is received,
653 	 * but delay each re-send by an increasing amount.
654 	 * If the delay hits the maximum, start complaining.
655 	 */
656 	timo = 0;
657 	rtimo = 0;
658 	for (;;) {
659 
660 		outstanding = 0;
661 		gotrootpath = 0;
662 
663 		for (ifctx = gctx->interfaces;
664 		     ifctx != NULL;
665 		     ifctx = ifctx->next) {
666 			if (bootpc_ifctx_isresolved(ifctx) != 0 &&
667 			    bootpc_tag(&gctx->tmptag, &ifctx->reply,
668 				       ifctx->replylen,
669 				       TAG_ROOT) != NULL)
670 				gotrootpath = 1;
671 		}
672 
673 		for (ifctx = gctx->interfaces;
674 		     ifctx != NULL;
675 		     ifctx = ifctx->next) {
676 			ifctx->outstanding = 0;
677 			if (bootpc_ifctx_isresolved(ifctx)  != 0 &&
678 			    gotrootpath != 0) {
679 				continue;
680 			}
681 			if (bootpc_ifctx_isfailed(ifctx) != 0)
682 				continue;
683 
684 			outstanding++;
685 			ifctx->outstanding = 1;
686 
687 			/* Proceed to next step in DHCP negotiation */
688 			if ((ifctx->state == IF_DHCP_OFFERED &&
689 			     ifctx->dhcpquerytype != DHCP_REQUEST) ||
690 			    (ifctx->state == IF_DHCP_UNRESOLVED &&
691 			     ifctx->dhcpquerytype != DHCP_DISCOVER) ||
692 			    (ifctx->state == IF_BOOTP_UNRESOLVED &&
693 			     ifctx->dhcpquerytype != DHCP_NOMSG)) {
694 				ifctx->sentmsg = 0;
695 				bootpc_compose_query(ifctx, gctx, td);
696 			}
697 
698 			/* Send BOOTP request (or re-send). */
699 
700 			if (ifctx->sentmsg == 0) {
701 				switch(ifctx->dhcpquerytype) {
702 				case DHCP_DISCOVER:
703 					s = "DHCP Discover";
704 					break;
705 				case DHCP_REQUEST:
706 					s = "DHCP Request";
707 					break;
708 				case DHCP_NOMSG:
709 				default:
710 					s = "BOOTP Query";
711 					break;
712 				}
713 				kprintf("Sending %s packet from "
714 				       "interface %s (%*D)\n",
715 				       s,
716 				       ifctx->ireq.ifr_name,
717 				       ifctx->sdl->sdl_alen,
718 				       (unsigned char *) LLADDR(ifctx->sdl),
719 				       ":");
720 				ifctx->sentmsg = 1;
721 			}
722 
723 			aio.iov_base = (caddr_t) &ifctx->call;
724 			aio.iov_len = sizeof(ifctx->call);
725 
726 			auio.uio_iov = &aio;
727 			auio.uio_iovcnt = 1;
728 			auio.uio_segflg = UIO_SYSSPACE;
729 			auio.uio_rw = UIO_WRITE;
730 			auio.uio_offset = 0;
731 			auio.uio_resid = sizeof(ifctx->call);
732 			auio.uio_td = td;
733 
734 			/* Set netmask to 0.0.0.0 */
735 
736 			sin = (struct sockaddr_in *) &ifctx->ireq.ifr_addr;
737 			clear_sinaddr(sin);
738 			error = ifioctl(ifctx->so, SIOCSIFNETMASK,
739 					(caddr_t) &ifctx->ireq, proc0.p_ucred);
740 			if (error != 0)
741 				panic("bootpc_call:"
742 				      "set if netmask, error=%d",
743 				      error);
744 
745 			error = sosend(so, (struct sockaddr *) &dst,
746 				       &auio, NULL, NULL, 0, td);
747 			if (error != 0) {
748 				kprintf("bootpc_call: sosend: %d state %08x\n",
749 				       error, (int) so->so_state);
750 			}
751 
752 			/* XXX: Is this needed ? */
753 			tsleep(&error, 0, "bootpw", 10);
754 
755 			/* Set netmask to 255.0.0.0 */
756 
757 			sin = (struct sockaddr_in *) &ifctx->ireq.ifr_addr;
758 			clear_sinaddr(sin);
759 			sin->sin_addr.s_addr = htonl(0xff000000u);
760 			error = ifioctl(ifctx->so, SIOCSIFNETMASK,
761 					(caddr_t) &ifctx->ireq, proc0.p_ucred);
762 			if (error != 0)
763 				panic("bootpc_call:"
764 				      "set if netmask, error=%d",
765 				      error);
766 
767 		}
768 
769 		if (outstanding == 0 &&
770 		    (rtimo == 0 || time_second >= rtimo)) {
771 			error = 0;
772 			goto gotreply;
773 		}
774 
775 		/* Determine new timeout. */
776 		if (timo < MAX_RESEND_DELAY)
777 			timo++;
778 		else {
779 			kprintf("DHCP/BOOTP timeout for server ");
780 			print_sin_addr(&dst);
781 			kprintf("\n");
782 		}
783 
784 		/*
785 		 * Wait for up to timo seconds for a reply.
786 		 * The socket receive timeout was set to 1 second.
787 		 */
788 		atimo = timo + time_second;
789 		while (time_second < atimo) {
790 			aio.iov_base = (caddr_t) &gctx->reply;
791 			aio.iov_len = sizeof(gctx->reply);
792 
793 			auio.uio_iov = &aio;
794 			auio.uio_iovcnt = 1;
795 			auio.uio_segflg = UIO_SYSSPACE;
796 			auio.uio_rw = UIO_READ;
797 			auio.uio_offset = 0;
798 			auio.uio_resid = sizeof(gctx->reply);
799 			auio.uio_td = td;
800 
801 			rcvflg = 0;
802 			error = soreceive(so, NULL, &auio,
803 					  NULL, NULL, &rcvflg);
804 			gctx->secs = time_second - gctx->starttime;
805 			for (ifctx = gctx->interfaces;
806 			     ifctx != NULL;
807 			     ifctx = ifctx->next) {
808 				if (bootpc_ifctx_isresolved(ifctx) != 0 ||
809 				    bootpc_ifctx_isfailed(ifctx) != 0)
810 					continue;
811 
812 				ifctx->call.secs = htons(gctx->secs);
813 			}
814 			if (error == EWOULDBLOCK)
815 				continue;
816 			if (error != 0)
817 				goto out;
818 			len = sizeof(gctx->reply) - auio.uio_resid;
819 
820 			/* Do we have the required number of bytes ? */
821 			if (len < BOOTP_MIN_LEN)
822 				continue;
823 			gctx->replylen = len;
824 
825 			/* Is it a reply? */
826 			if (gctx->reply.op != BOOTP_REPLY)
827 				continue;
828 
829 			/* Is this an answer to our query */
830 			for (ifctx = gctx->interfaces;
831 			     ifctx != NULL;
832 			     ifctx = ifctx->next) {
833 				if (gctx->reply.xid != ifctx->call.xid)
834 					continue;
835 
836 				/* Same HW address size ? */
837 				if (gctx->reply.hlen != ifctx->call.hlen)
838 					continue;
839 
840 				/* Correct HW address ? */
841 				if (bcmp(gctx->reply.chaddr,
842 					 ifctx->call.chaddr,
843 					 ifctx->call.hlen) != 0)
844 					continue;
845 
846 				break;
847 			}
848 
849 			if (ifctx != NULL) {
850 				s =  bootpc_tag(&gctx->tmptag,
851 						&gctx->reply,
852 						gctx->replylen,
853 						TAG_DHCP_MSGTYPE);
854 				if (s != NULL) {
855 					switch (*s) {
856 					case DHCP_OFFER:
857 						s = "DHCP Offer";
858 						break;
859 					case DHCP_ACK:
860 						s = "DHCP Ack";
861 						break;
862 					default:
863 						s = "DHCP (unexpected)";
864 						break;
865 					}
866 				} else
867 					s = "BOOTP Reply";
868 
869 				kprintf("Received %s packet"
870 				       " on %s from ",
871 				       s,
872 				       ifctx->ireq.ifr_name);
873 				print_in_addr(gctx->reply.siaddr);
874 				if (gctx->reply.giaddr.s_addr !=
875 				    htonl(INADDR_ANY)) {
876 					kprintf(" via ");
877 					print_in_addr(gctx->reply.giaddr);
878 				}
879 				if (bootpc_received(gctx, ifctx) != 0) {
880 					kprintf(" (accepted)");
881 					if (ifctx->outstanding) {
882 						ifctx->outstanding = 0;
883 						outstanding--;
884 					}
885 					/* Network settle delay */
886 					if (outstanding == 0)
887 						atimo = time_second +
888 							BOOTP_SETTLE_DELAY;
889 				} else
890 					kprintf(" (ignored)");
891 				if (ifctx->gotrootpath) {
892 					gotrootpath = 1;
893 					rtimo = time_second +
894 						BOOTP_SETTLE_DELAY;
895 					kprintf(" (got root path)");
896 				} else
897 					kprintf(" (no root path)");
898 				kprintf("\n");
899 			}
900 		} /* while secs */
901 #ifdef BOOTP_TIMEOUT
902 		if (gctx->secs > BOOTP_TIMEOUT && BOOTP_TIMEOUT > 0)
903 			break;
904 #endif
905 		/* Force a retry if halfway in DHCP negotiation */
906 		retry = 0;
907 		for (ifctx = gctx->interfaces; ifctx != NULL;
908 		     ifctx = ifctx->next) {
909 			if (ifctx->state == IF_DHCP_OFFERED) {
910 				if (ifctx->dhcpquerytype == DHCP_DISCOVER)
911 					retry = 1;
912 				else
913 					ifctx->state = IF_DHCP_UNRESOLVED;
914 			}
915 		}
916 
917 		if (retry != 0)
918 			continue;
919 
920 		if (gotrootpath != 0) {
921 			gctx->gotrootpath = gotrootpath;
922 			if (rtimo != 0 && time_second >= rtimo)
923 				break;
924 		}
925 	} /* forever send/receive */
926 
927 	/*
928 	 * XXX: These are errors of varying seriousness being silently
929 	 * ignored
930 	 */
931 
932 	for (ifctx = gctx->interfaces; ifctx != NULL; ifctx = ifctx->next) {
933 		if (bootpc_ifctx_isresolved(ifctx) == 0) {
934 			kprintf("%s timeout for interface %s\n",
935 			       ifctx->dhcpquerytype != DHCP_NOMSG ?
936 			       "DHCP" : "BOOTP",
937 			       ifctx->ireq.ifr_name);
938 		}
939 	}
940 	if (gctx->gotrootpath != 0) {
941 #if 0
942 		kprintf("Got a root path, ignoring remaining timeout\n");
943 #endif
944 		error = 0;
945 		goto out;
946 	}
947 #ifndef BOOTP_NFSROOT
948 	for (ifctx = gctx->interfaces; ifctx != NULL; ifctx = ifctx->next) {
949 		if (bootpc_ifctx_isresolved(ifctx) != 0) {
950 			error = 0;
951 			goto out;
952 		}
953 	}
954 #endif
955 	error = ETIMEDOUT;
956 	goto out;
957 
958 gotreply:
959 out:
960 	soclose(so, FNONBLOCK);
961 	return error;
962 }
963 
964 
965 static int
966 bootpc_fakeup_interface(struct bootpc_ifcontext *ifctx,
967 			struct bootpc_globalcontext *gctx,
968 			struct thread *td)
969 {
970 	struct sockaddr_in *sin;
971 	int error;
972 
973 	struct ifreq *ireq;
974 	struct socket *so;
975 	struct ifaddr *ifa;
976 	struct sockaddr_dl *sdl;
977 
978 	error = socreate(AF_INET, &ifctx->so, SOCK_DGRAM, 0, td);
979 	if (error != 0)
980 		panic("nfs_boot: socreate, error=%d", error);
981 
982 	ireq = &ifctx->ireq;
983 	so = ifctx->so;
984 
985 	/*
986 	 * Bring up the interface.
987 	 *
988 	 * Get the old interface flags and or IFF_UP into them; if
989 	 * IFF_UP set blindly, interface selection can be clobbered.
990 	 */
991 	error = ifioctl(so, SIOCGIFFLAGS, (caddr_t)ireq, proc0.p_ucred);
992 	if (error != 0)
993 		panic("bootpc_fakeup_interface: GIFFLAGS, error=%d", error);
994 	ireq->ifr_flags |= IFF_UP;
995 	error = ifioctl(so, SIOCSIFFLAGS, (caddr_t)ireq, proc0.p_ucred);
996 	if (error != 0)
997 		panic("bootpc_fakeup_interface: SIFFLAGS, error=%d", error);
998 
999 	/*
1000 	 * Do enough of ifconfig(8) so that the chosen interface
1001 	 * can talk to the servers.  (just set the address)
1002 	 */
1003 
1004 	/* addr is 0.0.0.0 */
1005 
1006 	sin = (struct sockaddr_in *) &ireq->ifr_addr;
1007 	clear_sinaddr(sin);
1008 	error = ifioctl(so, SIOCSIFADDR, (caddr_t) ireq, proc0.p_ucred);
1009 	if (error != 0 && (error != EEXIST || ifctx == gctx->interfaces))
1010 		panic("bootpc_fakeup_interface: "
1011 		      "set if addr, error=%d", error);
1012 
1013 	/* netmask is 255.0.0.0 */
1014 
1015 	sin = (struct sockaddr_in *) &ireq->ifr_addr;
1016 	clear_sinaddr(sin);
1017 	sin->sin_addr.s_addr = htonl(0xff000000u);
1018 	error = ifioctl(so, SIOCSIFNETMASK, (caddr_t)ireq, proc0.p_ucred);
1019 	if (error != 0)
1020 		panic("bootpc_fakeup_interface: set if netmask, error=%d",
1021 		      error);
1022 
1023 	/* Broadcast is 255.255.255.255 */
1024 
1025 	sin = (struct sockaddr_in *)&ireq->ifr_addr;
1026 	clear_sinaddr(sin);
1027 	clear_sinaddr(&ifctx->broadcast);
1028 	sin->sin_addr.s_addr = htonl(INADDR_BROADCAST);
1029 	ifctx->broadcast.sin_addr.s_addr = sin->sin_addr.s_addr;
1030 
1031 	error = ifioctl(so, SIOCSIFBRDADDR, (caddr_t)ireq, proc0.p_ucred);
1032 	if (error != 0 && error != EADDRNOTAVAIL)
1033 		panic("bootpc_fakeup_interface: "
1034 		      "set if broadcast addr, error=%d",
1035 		      error);
1036 	error = 0;
1037 
1038 	/* Get HW address */
1039 
1040 	sdl = NULL;
1041 	TAILQ_FOREACH(ifa, &ifctx->ifp->if_addrhead, ifa_link)
1042 		if (ifa->ifa_addr->sa_family == AF_LINK &&
1043 		    (sdl = ((struct sockaddr_dl *) ifa->ifa_addr)) != NULL &&
1044 		    sdl->sdl_type == IFT_ETHER)
1045 			break;
1046 
1047 	if (sdl == NULL)
1048 		panic("bootpc: Unable to find HW address for %s",
1049 		      ifctx->ireq.ifr_name);
1050 	ifctx->sdl = sdl;
1051 
1052 	return error;
1053 }
1054 
1055 
1056 static int
1057 bootpc_adjust_interface(struct bootpc_ifcontext *ifctx,
1058 			struct bootpc_globalcontext *gctx,
1059 			struct thread *td)
1060 {
1061 	int error;
1062 	struct sockaddr_in defdst;
1063 	struct sockaddr_in defmask;
1064 	struct sockaddr_in *sin;
1065 
1066 	struct ifreq *ireq;
1067 	struct socket *so;
1068 	struct sockaddr_in *myaddr;
1069 	struct sockaddr_in *netmask;
1070 	struct sockaddr_in *gw;
1071 
1072 	ireq = &ifctx->ireq;
1073 	so = ifctx->so;
1074 	myaddr = &ifctx->myaddr;
1075 	netmask = &ifctx->netmask;
1076 	gw = &ifctx->gw;
1077 
1078 	if (bootpc_ifctx_isresolved(ifctx) == 0) {
1079 
1080 		/* Shutdown interfaces where BOOTP failed */
1081 
1082 		kprintf("Shutdown interface %s\n", ifctx->ireq.ifr_name);
1083 		error = ifioctl(so, SIOCGIFFLAGS, (caddr_t)ireq, proc0.p_ucred);
1084 		if (error != 0)
1085 			panic("bootpc_adjust_interface: "
1086 			      "SIOCGIFFLAGS, error=%d", error);
1087 		ireq->ifr_flags &= ~IFF_UP;
1088 		error = ifioctl(so, SIOCSIFFLAGS, (caddr_t)ireq, proc0.p_ucred);
1089 		if (error != 0)
1090 			panic("bootpc_adjust_interface: "
1091 			      "SIOCSIFFLAGS, error=%d", error);
1092 
1093 		sin = (struct sockaddr_in *) &ireq->ifr_addr;
1094 		clear_sinaddr(sin);
1095 		error = ifioctl(so, SIOCDIFADDR, (caddr_t) ireq, proc0.p_ucred);
1096 		if (error != 0 && (error != EADDRNOTAVAIL ||
1097 				   ifctx == gctx->interfaces))
1098 			panic("bootpc_adjust_interface: "
1099 			      "SIOCDIFADDR, error=%d", error);
1100 
1101 		return 0;
1102 	}
1103 
1104 	kprintf("Adjusted interface %s\n", ifctx->ireq.ifr_name);
1105 	/*
1106 	 * Do enough of ifconfig(8) so that the chosen interface
1107 	 * can talk to the servers.  (just set the address)
1108 	 */
1109 	bcopy(netmask, &ireq->ifr_addr, sizeof(*netmask));
1110 	error = ifioctl(so, SIOCSIFNETMASK, (caddr_t) ireq, proc0.p_ucred);
1111 	if (error != 0)
1112 		panic("bootpc_adjust_interface: "
1113 		      "set if netmask, error=%d", error);
1114 
1115 	/* Broadcast is with host part of IP address all 1's */
1116 
1117 	sin = (struct sockaddr_in *) &ireq->ifr_addr;
1118 	clear_sinaddr(sin);
1119 	sin->sin_addr.s_addr = myaddr->sin_addr.s_addr |
1120 		~ netmask->sin_addr.s_addr;
1121 	error = ifioctl(so, SIOCSIFBRDADDR, (caddr_t) ireq, proc0.p_ucred);
1122 	if (error != 0)
1123 		panic("bootpc_adjust_interface: "
1124 		      "set if broadcast addr, error=%d", error);
1125 
1126 	bcopy(myaddr, &ireq->ifr_addr, sizeof(*myaddr));
1127 	error = ifioctl(so, SIOCSIFADDR, (caddr_t) ireq, proc0.p_ucred);
1128 	if (error != 0 && (error != EEXIST || ifctx == gctx->interfaces))
1129 		panic("bootpc_adjust_interface: "
1130 		      "set if addr, error=%d", error);
1131 
1132 	/* Add new default route */
1133 
1134 	if (ifctx->gotgw != 0 || gctx->gotgw == 0) {
1135 		clear_sinaddr(&defdst);
1136 		clear_sinaddr(&defmask);
1137 		error = rtrequest_global(RTM_ADD, (struct sockaddr *) &defdst,
1138 					 (struct sockaddr *) gw,
1139 					 (struct sockaddr *) &defmask,
1140 					 (RTF_UP | RTF_GATEWAY | RTF_STATIC));
1141 		if (error != 0) {
1142 			kprintf("bootpc_adjust_interface: "
1143 			       "add net route, error=%d\n", error);
1144 			return error;
1145 		}
1146 	}
1147 
1148 	return 0;
1149 }
1150 
1151 static void
1152 print_sin_addr(struct sockaddr_in *sin)
1153 {
1154 	print_in_addr(sin->sin_addr);
1155 }
1156 
1157 
1158 static void
1159 print_in_addr(struct in_addr addr)
1160 {
1161 	unsigned int ip;
1162 
1163 	ip = ntohl(addr.s_addr);
1164 	kprintf("%d.%d.%d.%d",
1165 	       ip >> 24, (ip >> 16) & 255, (ip >> 8) & 255, ip & 255);
1166 }
1167 
1168 static void
1169 bootpc_compose_query(struct bootpc_ifcontext *ifctx,
1170 		     struct bootpc_globalcontext *gctx, struct thread *td)
1171 {
1172 	unsigned char *vendp;
1173 	unsigned char vendor_client[64];
1174 	uint32_t leasetime;
1175 	uint8_t vendor_client_len;
1176 
1177 	ifctx->gotrootpath = 0;
1178 
1179 	bzero((caddr_t) &ifctx->call, sizeof(ifctx->call));
1180 
1181 	/* bootpc part */
1182 	ifctx->call.op = BOOTP_REQUEST; 	/* BOOTREQUEST */
1183 	ifctx->call.htype = 1;			/* 10mb ethernet */
1184 	ifctx->call.hlen = ifctx->sdl->sdl_alen;/* Hardware address length */
1185 	ifctx->call.hops = 0;
1186 	if (bootpc_ifctx_isunresolved(ifctx) != 0)
1187 		ifctx->xid++;
1188 	ifctx->call.xid = txdr_unsigned(ifctx->xid);
1189 	bcopy(LLADDR(ifctx->sdl), &ifctx->call.chaddr, ifctx->sdl->sdl_alen);
1190 
1191 	vendp = ifctx->call.vend;
1192 	*vendp++ = 99;		/* RFC1048 cookie */
1193 	*vendp++ = 130;
1194 	*vendp++ = 83;
1195 	*vendp++ = 99;
1196 	*vendp++ = TAG_MAXMSGSIZE;
1197 	*vendp++ = 2;
1198 	*vendp++ = (sizeof(struct bootp_packet) >> 8) & 255;
1199 	*vendp++ = sizeof(struct bootp_packet) & 255;
1200 
1201 	ksnprintf(vendor_client, sizeof(vendor_client), "%s:%s:%s",
1202 		ostype, MACHINE, osrelease);
1203 	vendor_client_len = strlen(vendor_client);
1204 	*vendp++ = TAG_VENDOR_INDENTIFIER;
1205 	*vendp++ = vendor_client_len;
1206 	memcpy(vendp, vendor_client, vendor_client_len);
1207 	vendp += vendor_client_len;
1208 	ifctx->dhcpquerytype = DHCP_NOMSG;
1209 	switch (ifctx->state) {
1210 	case IF_DHCP_UNRESOLVED:
1211 		*vendp++ = TAG_DHCP_MSGTYPE;
1212 		*vendp++ = 1;
1213 		*vendp++ = DHCP_DISCOVER;
1214 		ifctx->dhcpquerytype = DHCP_DISCOVER;
1215 		ifctx->gotdhcpserver = 0;
1216 		break;
1217 	case IF_DHCP_OFFERED:
1218 		*vendp++ = TAG_DHCP_MSGTYPE;
1219 		*vendp++ = 1;
1220 		*vendp++ = DHCP_REQUEST;
1221 		ifctx->dhcpquerytype = DHCP_REQUEST;
1222 		*vendp++ = TAG_DHCP_REQ_ADDR;
1223 		*vendp++ = 4;
1224 		memcpy(vendp, &ifctx->reply.yiaddr, 4);
1225 		vendp += 4;
1226 		if (ifctx->gotdhcpserver != 0) {
1227 			*vendp++ = TAG_DHCP_SERVERID;
1228 			*vendp++ = 4;
1229 			memcpy(vendp, &ifctx->dhcpserver, 4);
1230 			vendp += 4;
1231 		}
1232 		*vendp++ = TAG_DHCP_LEASETIME;
1233 		*vendp++ = 4;
1234 		leasetime = htonl(300);
1235 		memcpy(vendp, &leasetime, 4);
1236 		vendp += 4;
1237 	default:
1238 		;
1239 	}
1240 	*vendp = TAG_END;
1241 
1242 	ifctx->call.secs = 0;
1243 	ifctx->call.flags = htons(0x8000); /* We need an broadcast answer */
1244 }
1245 
1246 
1247 static int
1248 bootpc_hascookie(struct bootp_packet *bp)
1249 {
1250 	return (bp->vend[0] == 99 && bp->vend[1] == 130 &&
1251 		bp->vend[2] == 83 && bp->vend[3] == 99);
1252 }
1253 
1254 
1255 static void
1256 bootpc_tag_helper(struct bootpc_tagcontext *tctx,
1257 		  unsigned char *start, int len, int tag)
1258 {
1259 	unsigned char *j;
1260 	unsigned char *ej;
1261 	unsigned char code;
1262 
1263 	if (tctx->badtag != 0 || tctx->badopt != 0)
1264 		return;
1265 
1266 	j = start;
1267 	ej = j + len;
1268 
1269 	while (j < ej) {
1270 		code = *j++;
1271 		if (code == TAG_PAD)
1272 			continue;
1273 		if (code == TAG_END)
1274 			return;
1275 		if (j >= ej || j + *j + 1 > ej) {
1276 			tctx->badopt = 1;
1277 			return;
1278 		}
1279 		len = *j++;
1280 		if (code == tag) {
1281 			if (tctx->taglen + len > TAG_MAXLEN) {
1282 				tctx->badtag = 1;
1283 				return;
1284 			}
1285 			tctx->foundopt = 1;
1286 			if (len > 0)
1287 				memcpy(tctx->buf + tctx->taglen,
1288 				       j, len);
1289 			tctx->taglen += len;
1290 		}
1291 		if (code == TAG_OVERLOAD)
1292 			tctx->overload = *j;
1293 
1294 		j += len;
1295 	}
1296 }
1297 
1298 
1299 static unsigned char *
1300 bootpc_tag(struct bootpc_tagcontext *tctx, struct bootp_packet *bp,
1301 	   int len, int tag)
1302 {
1303 	unsigned char *j;
1304 	unsigned char *ej;
1305 
1306 	tctx->overload = 0;
1307 	tctx->badopt = 0;
1308 	tctx->badtag = 0;
1309 	tctx->foundopt = 0;
1310 	tctx->taglen = 0;
1311 
1312 	if (bootpc_hascookie(bp) == 0)
1313 		return NULL;
1314 
1315 	j = &bp->vend[4];
1316 	ej = (unsigned char *) bp + len;
1317 
1318 	bootpc_tag_helper(tctx, &bp->vend[4],
1319 			  (unsigned char *) bp + len - &bp->vend[4], tag);
1320 
1321 	if ((tctx->overload & OVERLOAD_FILE) != 0)
1322 		bootpc_tag_helper(tctx,
1323 				  (unsigned char *) bp->file,
1324 				  sizeof(bp->file),
1325 				  tag);
1326 	if ((tctx->overload & OVERLOAD_SNAME) != 0)
1327 		bootpc_tag_helper(tctx,
1328 				  (unsigned char *) bp->sname,
1329 				  sizeof(bp->sname),
1330 				  tag);
1331 
1332 	if (tctx->badopt != 0 || tctx->badtag != 0 || tctx->foundopt == 0)
1333 		return NULL;
1334 	tctx->buf[tctx->taglen] = '\0';
1335 	return tctx->buf;
1336 }
1337 
1338 
1339 static void
1340 bootpc_decode_reply(struct nfsv3_diskless *nd, struct bootpc_ifcontext *ifctx,
1341 		    struct bootpc_globalcontext *gctx)
1342 {
1343 	char *p;
1344 	unsigned int ip;
1345 
1346 	ifctx->gotgw = 0;
1347 	ifctx->gotnetmask = 0;
1348 
1349 	clear_sinaddr(&ifctx->myaddr);
1350 	clear_sinaddr(&ifctx->netmask);
1351 	clear_sinaddr(&ifctx->gw);
1352 
1353 	ifctx->myaddr.sin_addr = ifctx->reply.yiaddr;
1354 
1355 	ip = ntohl(ifctx->myaddr.sin_addr.s_addr);
1356 	ksnprintf(gctx->lookup_path, sizeof(gctx->lookup_path),
1357 		 "swap.%d.%d.%d.%d",
1358 		 ip >> 24, (ip >> 16) & 255, (ip >> 8) & 255, ip & 255);
1359 
1360 	kprintf("%s at ", ifctx->ireq.ifr_name);
1361 	print_sin_addr(&ifctx->myaddr);
1362 	kprintf(" server ");
1363 	print_in_addr(ifctx->reply.siaddr);
1364 
1365 	ifctx->gw.sin_addr = ifctx->reply.giaddr;
1366 	if (ifctx->reply.giaddr.s_addr != htonl(INADDR_ANY)) {
1367 		kprintf(" via gateway ");
1368 		print_in_addr(ifctx->reply.giaddr);
1369 	}
1370 
1371 	/* This call used for the side effect (overload flag) */
1372 	(void) bootpc_tag(&gctx->tmptag,
1373 			  &ifctx->reply, ifctx->replylen, TAG_END);
1374 
1375 	if ((gctx->tmptag.overload & OVERLOAD_SNAME) == 0)
1376 		if (ifctx->reply.sname[0] != '\0')
1377 			kprintf(" server name %s", ifctx->reply.sname);
1378 	if ((gctx->tmptag.overload & OVERLOAD_FILE) == 0)
1379 		if (ifctx->reply.file[0] != '\0')
1380 			kprintf(" boot file %s", ifctx->reply.file);
1381 
1382 	kprintf("\n");
1383 
1384 	p = bootpc_tag(&gctx->tag, &ifctx->reply, ifctx->replylen,
1385 		       TAG_SUBNETMASK);
1386 	if (p != NULL) {
1387 		if (gctx->tag.taglen != 4)
1388 			panic("bootpc: subnet mask len is %d",
1389 			      gctx->tag.taglen);
1390 		bcopy(p, &ifctx->netmask.sin_addr, 4);
1391 		ifctx->gotnetmask = 1;
1392 		kprintf("subnet mask ");
1393 		print_sin_addr(&ifctx->netmask);
1394 		kprintf(" ");
1395 	}
1396 
1397 	p = bootpc_tag(&gctx->tag, &ifctx->reply, ifctx->replylen,
1398 		       TAG_ROUTERS);
1399 	if (p != NULL) {
1400 		/* Routers */
1401 		if (gctx->tag.taglen % 4)
1402 			panic("bootpc: Router Len is %d", gctx->tag.taglen);
1403 		if (gctx->tag.taglen > 0) {
1404 			bcopy(p, &ifctx->gw.sin_addr, 4);
1405 			kprintf("router ");
1406 			print_sin_addr(&ifctx->gw);
1407 			kprintf(" ");
1408 			ifctx->gotgw = 1;
1409 			gctx->gotgw = 1;
1410 		}
1411 	}
1412 
1413 	p = bootpc_tag(&gctx->tag, &ifctx->reply, ifctx->replylen,
1414 		       TAG_ROOT);
1415 	if (p != NULL) {
1416 		if (gctx->setrootfs != NULL) {
1417 			kprintf("rootfs %s (ignored) ", p);
1418 		} else 	if (setfs(&nd->root_saddr,
1419 				  nd->root_hostnam, p)) {
1420 			kprintf("rootfs %s ",p);
1421 			gctx->gotrootpath = 1;
1422 			ifctx->gotrootpath = 1;
1423 			gctx->setrootfs = ifctx;
1424 
1425 			p = bootpc_tag(&gctx->tag, &ifctx->reply,
1426 				       ifctx->replylen,
1427 				       TAG_ROOTOPTS);
1428 			if (p != NULL) {
1429 				mountopts(&nd->root_args, p);
1430 				kprintf("rootopts %s ", p);
1431 			}
1432 		} else
1433 			panic("Failed to set rootfs to %s",p);
1434 	}
1435 
1436 	p = bootpc_tag(&gctx->tag, &ifctx->reply, ifctx->replylen,
1437 		       TAG_SWAP);
1438 	if (p != NULL) {
1439 		if (gctx->setswapfs != NULL) {
1440 			kprintf("swapfs %s (ignored) ", p);
1441 		} else 	if (setfs(&nd->swap_saddr,
1442 				  nd->swap_hostnam, p)) {
1443 			gctx->gotswappath = 1;
1444 			gctx->setswapfs = ifctx;
1445 			kprintf("swapfs %s ", p);
1446 
1447 			p = bootpc_tag(&gctx->tag, &ifctx->reply,
1448 				       ifctx->replylen,
1449 				       TAG_SWAPOPTS);
1450 			if (p != NULL) {
1451 				/* swap mount options */
1452 				mountopts(&nd->swap_args, p);
1453 				kprintf("swapopts %s ", p);
1454 			}
1455 
1456 			p = bootpc_tag(&gctx->tag, &ifctx->reply,
1457 				       ifctx->replylen,
1458 				       TAG_SWAPSIZE);
1459 			if (p != NULL) {
1460 				int swaplen;
1461 				if (gctx->tag.taglen != 4)
1462 					panic("bootpc: "
1463 					      "Expected 4 bytes for swaplen, "
1464 					      "not %d bytes",
1465 					      gctx->tag.taglen);
1466 				bcopy(p, &swaplen, 4);
1467 				nd->swap_nblks = ntohl(swaplen);
1468 				kprintf("swapsize %d KB ",
1469 				       nd->swap_nblks);
1470 			}
1471 		} else
1472 			panic("Failed to set swapfs to %s", p);
1473 	}
1474 
1475 	p = bootpc_tag(&gctx->tag, &ifctx->reply, ifctx->replylen,
1476 		       TAG_HOSTNAME);
1477 	if (p != NULL) {
1478 		if (gctx->tag.taglen >= MAXHOSTNAMELEN)
1479 			panic("bootpc: hostname >= %d bytes",
1480 			      MAXHOSTNAMELEN);
1481 		if (gctx->sethostname != NULL) {
1482 			kprintf("hostname %s (ignored) ", p);
1483 		} else {
1484 			strcpy(nd->my_hostnam, p);
1485 			strcpy(hostname, p);
1486 			kprintf("hostname %s ",hostname);
1487 			gctx->sethostname = ifctx;
1488 		}
1489 	}
1490 	p = bootpc_tag(&gctx->tag, &ifctx->reply, ifctx->replylen,
1491 		       TAG_COOKIE);
1492 	if (p != NULL) {	/* store in a sysctl variable */
1493 		int i, l = sizeof(bootp_cookie) - 1;
1494 		for (i = 0; i < l && p[i] != '\0'; i++)
1495 			bootp_cookie[i] = p[i];
1496 		p[i] = '\0';
1497 	}
1498 
1499 	kprintf("\n");
1500 
1501 	if (ifctx->gotnetmask == 0) {
1502 		if (IN_CLASSA(ntohl(ifctx->myaddr.sin_addr.s_addr)))
1503 			ifctx->netmask.sin_addr.s_addr = htonl(IN_CLASSA_NET);
1504 		else if (IN_CLASSB(ntohl(ifctx->myaddr.sin_addr.s_addr)))
1505 			ifctx->netmask.sin_addr.s_addr = htonl(IN_CLASSB_NET);
1506 		else
1507 			ifctx->netmask.sin_addr.s_addr = htonl(IN_CLASSC_NET);
1508 	}
1509 	if (ifctx->gotgw == 0) {
1510 		/* Use proxyarp */
1511 		ifctx->gw.sin_addr.s_addr = ifctx->myaddr.sin_addr.s_addr;
1512 	}
1513 }
1514 
1515 void
1516 bootpc_init(void)
1517 {
1518 	struct bootpc_ifcontext *ifctx, *nctx;	/* Interface BOOTP contexts */
1519 	struct bootpc_globalcontext *gctx; 	/* Global BOOTP context */
1520 	struct ifnet *ifp;
1521 	int error;
1522 	struct nfsv3_diskless *nd;
1523 	struct thread *td;
1524 
1525 	nd = &nfsv3_diskless;
1526 	td = curthread;
1527 
1528 	/*
1529 	 * If already filled in, don't touch it here
1530 	 */
1531 	if (nfs_diskless_valid != 0)
1532 		return;
1533 
1534 	/*
1535 	 * Wait until arp entries can be handled.
1536 	 */
1537 	while (time_second == 0)
1538 		tsleep(&time_second, 0, "arpkludge", 10);
1539 
1540 	gctx = kmalloc(sizeof(*gctx), M_TEMP, M_WAITOK | M_ZERO);
1541 
1542 	gctx->xid = ~0xFFFF;
1543 	gctx->starttime = time_second;
1544 
1545 	ifctx = allocifctx(gctx);
1546 
1547 	/*
1548 	 * Find a network interface.
1549 	 */
1550 #ifdef BOOTP_WIRED_TO
1551 	kprintf("bootpc_init: wired to interface '%s'\n",
1552 	       __XSTRING(BOOTP_WIRED_TO));
1553 #endif
1554 	bzero(&ifctx->ireq, sizeof(ifctx->ireq));
1555 	TAILQ_FOREACH(ifp, &ifnet, if_link) {
1556 		strlcpy(ifctx->ireq.ifr_name, ifp->if_xname,
1557 			 sizeof(ifctx->ireq.ifr_name));
1558 #ifdef BOOTP_WIRED_TO
1559 		if (strcmp(ifctx->ireq.ifr_name,
1560 			   __XSTRING(BOOTP_WIRED_TO)) != 0)
1561 			continue;
1562 #else
1563 		if ((ifp->if_flags &
1564 		     (IFF_LOOPBACK | IFF_POINTOPOINT | IFF_BROADCAST)) !=
1565 		    IFF_BROADCAST)
1566 			continue;
1567 #endif
1568 		if (gctx->interfaces != NULL)
1569 			gctx->lastinterface->next = ifctx;
1570 		else
1571 			gctx->interfaces = ifctx;
1572 		ifctx->ifp = ifp;
1573 		gctx->lastinterface = ifctx;
1574 		ifctx = allocifctx(gctx);
1575 	}
1576 	kfree(ifctx, M_TEMP);
1577 
1578 	if (gctx->interfaces == NULL) {
1579 #ifdef BOOTP_WIRED_TO
1580 		panic("bootpc_init: Could not find interface specified "
1581 		      "by BOOTP_WIRED_TO: "
1582 		      __XSTRING(BOOTP_WIRED_TO));
1583 #else
1584 		panic("bootpc_init: no suitable interface");
1585 #endif
1586 	}
1587 
1588 	gctx->gotrootpath = 0;
1589 	gctx->gotswappath = 0;
1590 	gctx->gotgw = 0;
1591 
1592 	for (ifctx = gctx->interfaces; ifctx != NULL; ifctx = ifctx->next)
1593 		bootpc_fakeup_interface(ifctx, gctx, td);
1594 
1595 	for (ifctx = gctx->interfaces; ifctx != NULL; ifctx = ifctx->next)
1596 		bootpc_compose_query(ifctx, gctx, td);
1597 
1598 	ifctx = gctx->interfaces;
1599 	error = bootpc_call(gctx, td);
1600 
1601 	if (error != 0) {
1602 #ifdef BOOTP_NFSROOT
1603 		panic("BOOTP call failed");
1604 #else
1605 		kprintf("BOOTP call failed\n");
1606 #endif
1607 	}
1608 
1609 	mountopts(&nd->root_args, NULL);
1610 
1611 	mountopts(&nd->swap_args, NULL);
1612 
1613 	for (ifctx = gctx->interfaces; ifctx != NULL; ifctx = ifctx->next)
1614 		if (bootpc_ifctx_isresolved(ifctx) != 0)
1615 			bootpc_decode_reply(nd, ifctx, gctx);
1616 
1617 	if (gctx->gotswappath == 0)
1618 		nd->swap_nblks = 0;
1619 #ifdef BOOTP_NFSROOT
1620 	if (gctx->gotrootpath == 0)
1621 		panic("bootpc: No root path offered");
1622 #endif
1623 
1624 	for (ifctx = gctx->interfaces; ifctx != NULL; ifctx = ifctx->next) {
1625 		bootpc_adjust_interface(ifctx, gctx, td);
1626 
1627 		soclose(ifctx->so, FNONBLOCK);
1628 	}
1629 
1630 	for (ifctx = gctx->interfaces; ifctx != NULL; ifctx = ifctx->next)
1631 		if (ifctx->gotrootpath != 0)
1632 			break;
1633 	if (ifctx == NULL) {
1634 		for (ifctx = gctx->interfaces;
1635 		     ifctx != NULL;
1636 		     ifctx = ifctx->next)
1637 			if (bootpc_ifctx_isresolved(ifctx) != 0)
1638 				break;
1639 	}
1640 	if (ifctx == NULL)
1641 		goto out;
1642 
1643 	if (gctx->gotrootpath != 0) {
1644 
1645 		error = md_mount(&nd->root_saddr, nd->root_hostnam,
1646 				 nd->root_fh, &nd->root_fhsize,
1647 				 &nd->root_args, td);
1648 		if (error != 0)
1649 			panic("nfs_boot: mountd root, error=%d", error);
1650 
1651 		if (gctx->gotswappath != 0) {
1652 
1653 			error = md_mount(&nd->swap_saddr,
1654 					 nd->swap_hostnam,
1655 					 nd->swap_fh, &nd->swap_fhsize,
1656 					 &nd->swap_args, td);
1657 			if (error != 0)
1658 				panic("nfs_boot: mountd swap, error=%d",
1659 				      error);
1660 
1661 			error = md_lookup_swap(&nd->swap_saddr,
1662 					       gctx->lookup_path,
1663 					       nd->swap_fh, &nd->swap_fhsize,
1664 					       &nd->swap_args, td);
1665 			if (error != 0)
1666 				panic("nfs_boot: lookup swap, error=%d",
1667 				      error);
1668 		}
1669 		nfs_diskless_valid = 3;
1670 	}
1671 
1672 	strcpy(nd->myif.ifra_name, ifctx->ireq.ifr_name);
1673 	bcopy(&ifctx->myaddr, &nd->myif.ifra_addr, sizeof(ifctx->myaddr));
1674 	bcopy(&ifctx->myaddr, &nd->myif.ifra_broadaddr, sizeof(ifctx->myaddr));
1675 	((struct sockaddr_in *) &nd->myif.ifra_broadaddr)->sin_addr.s_addr =
1676 		ifctx->myaddr.sin_addr.s_addr |
1677 		~ ifctx->netmask.sin_addr.s_addr;
1678 	bcopy(&ifctx->netmask, &nd->myif.ifra_mask, sizeof(ifctx->netmask));
1679 
1680 out:
1681 	for (ifctx = gctx->interfaces; ifctx != NULL; ifctx = nctx) {
1682 		nctx = ifctx->next;
1683 		kfree(ifctx, M_TEMP);
1684 	}
1685 	kfree(gctx, M_TEMP);
1686 }
1687 
1688