1 /*	$NetBSD: bootp_subr.c,v 1.1.1.1 2013/09/30 07:19:31 dholland Exp $	*/
2 /*-
3  * Copyright (c) 1995 Gordon Ross, Adam Glass
4  * Copyright (c) 1992 Regents of the University of California.
5  * All rights reserved.
6  *
7  * This software was developed by the Computer Systems Engineering group
8  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
9  * contributed to Berkeley.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. All advertising materials mentioning features or use of this software
20  *    must display the following acknowledgement:
21  *	This product includes software developed by the University of
22  *	California, Lawrence Berkeley Laboratory and its contributors.
23  * 4. Neither the name of the University nor the names of its contributors
24  *    may be used to endorse or promote products derived from this software
25  *    without specific prior written permission.
26  *
27  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37  * SUCH DAMAGE.
38  *
39  * based on:
40  *      nfs/krpc_subr.c
41  *	NetBSD: krpc_subr.c,v 1.10 1995/08/08 20:43:43 gwr Exp
42  */
43 
44 #include <sys/cdefs.h>
45 /* __FBSDID("FreeBSD: head/sys/nfs/bootp_subr.c 253847 2013-07-31 19:14:00Z ian "); */
46 __RCSID("$NetBSD: bootp_subr.c,v 1.1.1.1 2013/09/30 07:19:31 dholland Exp $");
47 
48 #include "opt_bootp.h"
49 #include "opt_nfs.h"
50 #include "opt_rootdevname.h"
51 
52 #include <sys/param.h>
53 #include <sys/systm.h>
54 #include <sys/jail.h>
55 #include <sys/kernel.h>
56 #include <sys/sockio.h>
57 #include <sys/malloc.h>
58 #include <sys/mount.h>
59 #include <sys/mbuf.h>
60 #include <sys/proc.h>
61 #include <sys/reboot.h>
62 #include <sys/socket.h>
63 #include <sys/socketvar.h>
64 #include <sys/sysctl.h>
65 #include <sys/uio.h>
66 
67 #include <net/if.h>
68 #include <net/route.h>
69 
70 #include <netinet/in.h>
71 #include <netinet/in_var.h>
72 #include <net/if_types.h>
73 #include <net/if_dl.h>
74 #include <net/vnet.h>
75 
76 #include <nfs/nfsproto.h>
77 #include <nfsclient/nfs.h>
78 #include <nfs/nfsdiskless.h>
79 #include <nfs/krpc.h>
80 #include <nfs/xdr_subs.h>
81 
82 
83 #define BOOTP_MIN_LEN		300	/* Minimum size of bootp udp packet */
84 
85 #ifndef BOOTP_SETTLE_DELAY
86 #define BOOTP_SETTLE_DELAY 3
87 #endif
88 
89 /*
90  * Wait 10 seconds for interface appearance
91  * USB ethernet adapters might require some time to pop up
92  */
93 #ifndef	BOOTP_IFACE_WAIT_TIMEOUT
94 #define	BOOTP_IFACE_WAIT_TIMEOUT	10
95 #endif
96 
97 /*
98  * What is the longest we will wait before re-sending a request?
99  * Note this is also the frequency of "RPC timeout" messages.
100  * The re-send loop count sup linearly to this maximum, so the
101  * first complaint will happen after (1+2+3+4+5)=15 seconds.
102  */
103 #define	MAX_RESEND_DELAY 5	/* seconds */
104 
105 /* Definitions from RFC951 */
106 struct bootp_packet {
107 	u_int8_t op;
108 	u_int8_t htype;
109 	u_int8_t hlen;
110 	u_int8_t hops;
111 	u_int32_t xid;
112 	u_int16_t secs;
113 	u_int16_t flags;
114 	struct in_addr ciaddr;
115 	struct in_addr yiaddr;
116 	struct in_addr siaddr;
117 	struct in_addr giaddr;
118 	unsigned char chaddr[16];
119 	char sname[64];
120 	char file[128];
121 	unsigned char vend[1222];
122 };
123 
124 struct bootpc_ifcontext {
125 	STAILQ_ENTRY(bootpc_ifcontext) next;
126 	struct bootp_packet call;
127 	struct bootp_packet reply;
128 	int replylen;
129 	int overload;
130 	union {
131 		struct ifreq _ifreq;
132 		struct in_aliasreq _in_alias_req;
133 	} _req;
134 #define	ireq	_req._ifreq
135 #define	iareq	_req._in_alias_req
136 	struct ifnet *ifp;
137 	struct sockaddr_dl *sdl;
138 	struct sockaddr_in myaddr;
139 	struct sockaddr_in netmask;
140 	struct sockaddr_in gw;
141 	int gotgw;
142 	int gotnetmask;
143 	int gotrootpath;
144 	int outstanding;
145 	int sentmsg;
146 	u_int32_t xid;
147 	enum {
148 		IF_BOOTP_UNRESOLVED,
149 		IF_BOOTP_RESOLVED,
150 		IF_BOOTP_FAILED,
151 		IF_DHCP_UNRESOLVED,
152 		IF_DHCP_OFFERED,
153 		IF_DHCP_RESOLVED,
154 		IF_DHCP_FAILED,
155 	} state;
156 	int dhcpquerytype;		/* dhcp type sent */
157 	struct in_addr dhcpserver;
158 	int gotdhcpserver;
159 };
160 
161 #define TAG_MAXLEN 1024
162 struct bootpc_tagcontext {
163 	char buf[TAG_MAXLEN + 1];
164 	int overload;
165 	int badopt;
166 	int badtag;
167 	int foundopt;
168 	int taglen;
169 };
170 
171 struct bootpc_globalcontext {
172 	STAILQ_HEAD(, bootpc_ifcontext) interfaces;
173 	u_int32_t xid;
174 	int any_root_overrides;
175 	int gotrootpath;
176 	int gotgw;
177 	int ifnum;
178 	int secs;
179 	int starttime;
180 	struct bootp_packet reply;
181 	int replylen;
182 	struct bootpc_ifcontext *setrootfs;
183 	struct bootpc_ifcontext *sethostname;
184 	struct bootpc_tagcontext tmptag;
185 	struct bootpc_tagcontext tag;
186 };
187 
188 #define IPPORT_BOOTPC 68
189 #define IPPORT_BOOTPS 67
190 
191 #define BOOTP_REQUEST 1
192 #define BOOTP_REPLY 2
193 
194 /* Common tags */
195 #define TAG_PAD		  0  /* Pad option, implicit length 1 */
196 #define TAG_SUBNETMASK	  1  /* RFC 950 subnet mask */
197 #define TAG_ROUTERS	  3  /* Routers (in order of preference) */
198 #define TAG_HOSTNAME	 12  /* Client host name */
199 #define TAG_ROOT	 17  /* Root path */
200 
201 /* DHCP specific tags */
202 #define TAG_OVERLOAD	 52  /* Option Overload */
203 #define TAG_MAXMSGSIZE   57  /* Maximum DHCP Message Size */
204 
205 #define TAG_END		255  /* End Option (i.e. no more options) */
206 
207 /* Overload values */
208 #define OVERLOAD_FILE     1
209 #define OVERLOAD_SNAME    2
210 
211 /* Site specific tags: */
212 #define TAG_ROOTOPTS	130
213 #define TAG_COOKIE	134	/* ascii info for userland, via sysctl */
214 
215 #define TAG_DHCP_MSGTYPE 53
216 #define TAG_DHCP_REQ_ADDR 50
217 #define TAG_DHCP_SERVERID 54
218 #define TAG_DHCP_LEASETIME 51
219 
220 #define TAG_VENDOR_INDENTIFIER 60
221 
222 #define DHCP_NOMSG    0
223 #define DHCP_DISCOVER 1
224 #define DHCP_OFFER    2
225 #define DHCP_REQUEST  3
226 #define DHCP_ACK      5
227 
228 /* NFS read/write block size */
229 #ifndef BOOTP_BLOCKSIZE
230 #define	BOOTP_BLOCKSIZE	8192
231 #endif
232 
233 static char bootp_cookie[128];
234 static struct socket *bootp_so;
235 SYSCTL_STRING(_kern, OID_AUTO, bootp_cookie, CTLFLAG_RD,
236 	bootp_cookie, 0, "Cookie (T134) supplied by bootp server");
237 
238 /* mountd RPC */
239 static int	md_mount(struct sockaddr_in *mdsin, char *path, u_char *fhp,
240 		    int *fhsizep, struct nfs_args *args, struct thread *td);
241 static int	setfs(struct sockaddr_in *addr, char *path, char *p,
242 		    const struct in_addr *siaddr);
243 static int	getdec(char **ptr);
244 static int	getip(char **ptr, struct in_addr *ip);
245 static void	mountopts(struct nfs_args *args, char *p);
246 static int	xdr_opaque_decode(struct mbuf **ptr, u_char *buf, int len);
247 static int	xdr_int_decode(struct mbuf **ptr, int *iptr);
248 static void	print_in_addr(struct in_addr addr);
249 static void	print_sin_addr(struct sockaddr_in *addr);
250 static void	clear_sinaddr(struct sockaddr_in *sin);
251 static void	allocifctx(struct bootpc_globalcontext *gctx);
252 static void	bootpc_compose_query(struct bootpc_ifcontext *ifctx,
253 		    struct thread *td);
254 static unsigned char *bootpc_tag(struct bootpc_tagcontext *tctx,
255 		    struct bootp_packet *bp, int len, int tag);
256 static void bootpc_tag_helper(struct bootpc_tagcontext *tctx,
257 		    unsigned char *start, int len, int tag);
258 
259 #ifdef BOOTP_DEBUG
260 void bootpboot_p_sa(struct sockaddr *sa, struct sockaddr *ma);
261 void bootpboot_p_rtentry(struct rtentry *rt);
262 void bootpboot_p_tree(struct radix_node *rn);
263 void bootpboot_p_rtlist(void);
264 void bootpboot_p_if(struct ifnet *ifp, struct ifaddr *ifa);
265 void bootpboot_p_iflist(void);
266 #endif
267 
268 static int	bootpc_call(struct bootpc_globalcontext *gctx,
269 		    struct thread *td);
270 
271 static void	bootpc_fakeup_interface(struct bootpc_ifcontext *ifctx,
272 		    struct thread *td);
273 
274 static int	bootpc_adjust_interface(struct bootpc_ifcontext *ifctx,
275 		    struct bootpc_globalcontext *gctx, struct thread *td);
276 
277 static void	bootpc_decode_reply(struct nfsv3_diskless *nd,
278 		    struct bootpc_ifcontext *ifctx,
279 		    struct bootpc_globalcontext *gctx);
280 
281 static int	bootpc_received(struct bootpc_globalcontext *gctx,
282 		    struct bootpc_ifcontext *ifctx);
283 
284 static __inline int bootpc_ifctx_isresolved(struct bootpc_ifcontext *ifctx);
285 static __inline int bootpc_ifctx_isunresolved(struct bootpc_ifcontext *ifctx);
286 static __inline int bootpc_ifctx_isfailed(struct bootpc_ifcontext *ifctx);
287 
288 /*
289  * In order to have multiple active interfaces with address 0.0.0.0
290  * and be able to send data to a selected interface, we first set
291  * mask to /8 on all interfaces, and temporarily set it to /0 when
292  * doing sosend().
293  */
294 
295 #ifdef BOOTP_DEBUG
296 void
bootpboot_p_sa(struct sockaddr * sa,struct sockaddr * ma)297 bootpboot_p_sa(struct sockaddr *sa, struct sockaddr *ma)
298 {
299 
300 	if (sa == NULL) {
301 		printf("(sockaddr *) <null>");
302 		return;
303 	}
304 	switch (sa->sa_family) {
305 	case AF_INET:
306 	{
307 		struct sockaddr_in *sin;
308 
309 		sin = (struct sockaddr_in *) sa;
310 		printf("inet ");
311 		print_sin_addr(sin);
312 		if (ma != NULL) {
313 			sin = (struct sockaddr_in *) ma;
314 			printf(" mask ");
315 			print_sin_addr(sin);
316 		}
317 	}
318 	break;
319 	case AF_LINK:
320 	{
321 		struct sockaddr_dl *sli;
322 		int i;
323 
324 		sli = (struct sockaddr_dl *) sa;
325 		printf("link %.*s ", sli->sdl_nlen, sli->sdl_data);
326 		for (i = 0; i < sli->sdl_alen; i++) {
327 			if (i > 0)
328 				printf(":");
329 			printf("%x", ((unsigned char *) LLADDR(sli))[i]);
330 		}
331 	}
332 	break;
333 	default:
334 		printf("af%d", sa->sa_family);
335 	}
336 }
337 
338 void
bootpboot_p_rtentry(struct rtentry * rt)339 bootpboot_p_rtentry(struct rtentry *rt)
340 {
341 
342 	bootpboot_p_sa(rt_key(rt), rt_mask(rt));
343 	printf(" ");
344 	bootpboot_p_sa(rt->rt_gateway, NULL);
345 	printf(" ");
346 	printf("flags %x", (unsigned short) rt->rt_flags);
347 	printf(" %d", (int) rt->rt_rmx.rmx_expire);
348 	printf(" %s\n", rt->rt_ifp->if_xname);
349 }
350 
351 void
bootpboot_p_tree(struct radix_node * rn)352 bootpboot_p_tree(struct radix_node *rn)
353 {
354 
355 	while (rn != NULL) {
356 		if (rn->rn_bit < 0) {
357 			if ((rn->rn_flags & RNF_ROOT) != 0) {
358 			} else {
359 				bootpboot_p_rtentry((struct rtentry *) rn);
360 			}
361 			rn = rn->rn_dupedkey;
362 		} else {
363 			bootpboot_p_tree(rn->rn_left);
364 			bootpboot_p_tree(rn->rn_right);
365 			return;
366 		}
367 	}
368 }
369 
370 void
bootpboot_p_rtlist(void)371 bootpboot_p_rtlist(void)
372 {
373 	struct radix_node_head *rnh;
374 
375 	printf("Routing table:\n");
376 	rnh = rt_tables_get_rnh(0, AF_INET);
377 	if (rnh == NULL)
378 		return;
379 	RADIX_NODE_HEAD_RLOCK(rnh);	/* could sleep XXX */
380 	bootpboot_p_tree(rnh->rnh_treetop);
381 	RADIX_NODE_HEAD_RUNLOCK(rnh);
382 }
383 
384 void
bootpboot_p_if(struct ifnet * ifp,struct ifaddr * ifa)385 bootpboot_p_if(struct ifnet *ifp, struct ifaddr *ifa)
386 {
387 
388 	printf("%s flags %x, addr ",
389 	       ifp->if_xname, ifp->if_flags);
390 	print_sin_addr((struct sockaddr_in *) ifa->ifa_addr);
391 	printf(", broadcast ");
392 	print_sin_addr((struct sockaddr_in *) ifa->ifa_dstaddr);
393 	printf(", netmask ");
394 	print_sin_addr((struct sockaddr_in *) ifa->ifa_netmask);
395 	printf("\n");
396 }
397 
398 void
bootpboot_p_iflist(void)399 bootpboot_p_iflist(void)
400 {
401 	struct ifnet *ifp;
402 	struct ifaddr *ifa;
403 
404 	printf("Interface list:\n");
405 	IFNET_RLOCK();
406 	for (ifp = TAILQ_FIRST(&V_ifnet);
407 	     ifp != NULL;
408 	     ifp = TAILQ_NEXT(ifp, if_link)) {
409 		for (ifa = TAILQ_FIRST(&ifp->if_addrhead);
410 		     ifa != NULL;
411 		     ifa = TAILQ_NEXT(ifa, ifa_link))
412 			if (ifa->ifa_addr->sa_family == AF_INET)
413 				bootpboot_p_if(ifp, ifa);
414 	}
415 	IFNET_RUNLOCK();
416 }
417 #endif /* defined(BOOTP_DEBUG) */
418 
419 static void
clear_sinaddr(struct sockaddr_in * sin)420 clear_sinaddr(struct sockaddr_in *sin)
421 {
422 
423 	bzero(sin, sizeof(*sin));
424 	sin->sin_len = sizeof(*sin);
425 	sin->sin_family = AF_INET;
426 	sin->sin_addr.s_addr = INADDR_ANY; /* XXX: htonl(INAADDR_ANY) ? */
427 	sin->sin_port = 0;
428 }
429 
430 static void
allocifctx(struct bootpc_globalcontext * gctx)431 allocifctx(struct bootpc_globalcontext *gctx)
432 {
433 	struct bootpc_ifcontext *ifctx;
434 
435 	ifctx = malloc(sizeof(*ifctx), M_TEMP, M_WAITOK | M_ZERO);
436 	ifctx->xid = gctx->xid;
437 #ifdef BOOTP_NO_DHCP
438 	ifctx->state = IF_BOOTP_UNRESOLVED;
439 #else
440 	ifctx->state = IF_DHCP_UNRESOLVED;
441 #endif
442 	gctx->xid += 0x100;
443 	STAILQ_INSERT_TAIL(&gctx->interfaces, ifctx, next);
444 }
445 
446 static __inline int
bootpc_ifctx_isresolved(struct bootpc_ifcontext * ifctx)447 bootpc_ifctx_isresolved(struct bootpc_ifcontext *ifctx)
448 {
449 
450 	if (ifctx->state == IF_BOOTP_RESOLVED ||
451 	    ifctx->state == IF_DHCP_RESOLVED)
452 		return 1;
453 	return 0;
454 }
455 
456 static __inline int
bootpc_ifctx_isunresolved(struct bootpc_ifcontext * ifctx)457 bootpc_ifctx_isunresolved(struct bootpc_ifcontext *ifctx)
458 {
459 
460 	if (ifctx->state == IF_BOOTP_UNRESOLVED ||
461 	    ifctx->state == IF_DHCP_UNRESOLVED)
462 		return 1;
463 	return 0;
464 }
465 
466 static __inline int
bootpc_ifctx_isfailed(struct bootpc_ifcontext * ifctx)467 bootpc_ifctx_isfailed(struct bootpc_ifcontext *ifctx)
468 {
469 
470 	if (ifctx->state == IF_BOOTP_FAILED ||
471 	    ifctx->state == IF_DHCP_FAILED)
472 		return 1;
473 	return 0;
474 }
475 
476 static int
bootpc_received(struct bootpc_globalcontext * gctx,struct bootpc_ifcontext * ifctx)477 bootpc_received(struct bootpc_globalcontext *gctx,
478     struct bootpc_ifcontext *ifctx)
479 {
480 	unsigned char dhcpreplytype;
481 	char *p;
482 
483 	/*
484 	 * Need timeout for fallback to less
485 	 * desirable alternative.
486 	 */
487 
488 	/* This call used for the side effect (badopt flag) */
489 	(void) bootpc_tag(&gctx->tmptag, &gctx->reply,
490 			  gctx->replylen,
491 			  TAG_END);
492 
493 	/* If packet is invalid, ignore it */
494 	if (gctx->tmptag.badopt != 0)
495 		return 0;
496 
497 	p = bootpc_tag(&gctx->tmptag, &gctx->reply,
498 		       gctx->replylen, TAG_DHCP_MSGTYPE);
499 	if (p != NULL)
500 		dhcpreplytype = *p;
501 	else
502 		dhcpreplytype = DHCP_NOMSG;
503 
504 	switch (ifctx->dhcpquerytype) {
505 	case DHCP_DISCOVER:
506 		if (dhcpreplytype != DHCP_OFFER 	/* Normal DHCP offer */
507 #ifndef BOOTP_FORCE_DHCP
508 		    && dhcpreplytype != DHCP_NOMSG	/* Fallback to BOOTP */
509 #endif
510 			)
511 			return 0;
512 		break;
513 	case DHCP_REQUEST:
514 		if (dhcpreplytype != DHCP_ACK)
515 			return 0;
516 	case DHCP_NOMSG:
517 		break;
518 	}
519 
520 	/* Ignore packet unless it gives us a root tag we didn't have */
521 
522 	if ((ifctx->state == IF_BOOTP_RESOLVED ||
523 	     (ifctx->dhcpquerytype == DHCP_DISCOVER &&
524 	      (ifctx->state == IF_DHCP_OFFERED ||
525 	       ifctx->state == IF_DHCP_RESOLVED))) &&
526 	    (bootpc_tag(&gctx->tmptag, &ifctx->reply,
527 			ifctx->replylen,
528 			TAG_ROOT) != NULL ||
529 	     bootpc_tag(&gctx->tmptag, &gctx->reply,
530 			gctx->replylen,
531 			TAG_ROOT) == NULL))
532 		return 0;
533 
534 	bcopy(&gctx->reply, &ifctx->reply, gctx->replylen);
535 	ifctx->replylen = gctx->replylen;
536 
537 	/* XXX: Only reset if 'perfect' response */
538 	if (ifctx->state == IF_BOOTP_UNRESOLVED)
539 		ifctx->state = IF_BOOTP_RESOLVED;
540 	else if (ifctx->state == IF_DHCP_UNRESOLVED &&
541 		 ifctx->dhcpquerytype == DHCP_DISCOVER) {
542 		if (dhcpreplytype == DHCP_OFFER)
543 			ifctx->state = IF_DHCP_OFFERED;
544 		else
545 			ifctx->state = IF_BOOTP_RESOLVED;	/* Fallback */
546 	} else if (ifctx->state == IF_DHCP_OFFERED &&
547 		   ifctx->dhcpquerytype == DHCP_REQUEST)
548 		ifctx->state = IF_DHCP_RESOLVED;
549 
550 
551 	if (ifctx->dhcpquerytype == DHCP_DISCOVER &&
552 	    ifctx->state != IF_BOOTP_RESOLVED) {
553 		p = bootpc_tag(&gctx->tmptag, &ifctx->reply,
554 			       ifctx->replylen, TAG_DHCP_SERVERID);
555 		if (p != NULL && gctx->tmptag.taglen == 4) {
556 			memcpy(&ifctx->dhcpserver, p, 4);
557 			ifctx->gotdhcpserver = 1;
558 		} else
559 			ifctx->gotdhcpserver = 0;
560 		return 1;
561 	}
562 
563 	ifctx->gotrootpath = (bootpc_tag(&gctx->tmptag, &ifctx->reply,
564 					 ifctx->replylen,
565 					 TAG_ROOT) != NULL);
566 	ifctx->gotgw = (bootpc_tag(&gctx->tmptag, &ifctx->reply,
567 				   ifctx->replylen,
568 				   TAG_ROUTERS) != NULL);
569 	ifctx->gotnetmask = (bootpc_tag(&gctx->tmptag, &ifctx->reply,
570 					ifctx->replylen,
571 					TAG_SUBNETMASK) != NULL);
572 	return 1;
573 }
574 
575 static int
bootpc_call(struct bootpc_globalcontext * gctx,struct thread * td)576 bootpc_call(struct bootpc_globalcontext *gctx, struct thread *td)
577 {
578 	struct sockaddr_in *sin, dst;
579 	struct uio auio;
580 	struct sockopt sopt;
581 	struct iovec aio;
582 	int error, on, rcvflg, timo, len;
583 	time_t atimo;
584 	time_t rtimo;
585 	struct timeval tv;
586 	struct bootpc_ifcontext *ifctx;
587 	int outstanding;
588 	int gotrootpath;
589 	int retry;
590 	const char *s;
591 
592 	tv.tv_sec = 1;
593 	tv.tv_usec = 0;
594 	bzero(&sopt, sizeof(sopt));
595 	sopt.sopt_dir = SOPT_SET;
596 	sopt.sopt_level = SOL_SOCKET;
597 	sopt.sopt_name = SO_RCVTIMEO;
598 	sopt.sopt_val = &tv;
599 	sopt.sopt_valsize = sizeof tv;
600 
601 	error = sosetopt(bootp_so, &sopt);
602 	if (error != 0)
603 		goto out;
604 
605 	/*
606 	 * Enable broadcast.
607 	 */
608 	on = 1;
609 	sopt.sopt_name = SO_BROADCAST;
610 	sopt.sopt_val = &on;
611 	sopt.sopt_valsize = sizeof on;
612 
613 	error = sosetopt(bootp_so, &sopt);
614 	if (error != 0)
615 		goto out;
616 
617 	/*
618 	 * Disable routing.
619 	 */
620 
621 	on = 1;
622 	sopt.sopt_name = SO_DONTROUTE;
623 	sopt.sopt_val = &on;
624 	sopt.sopt_valsize = sizeof on;
625 
626 	error = sosetopt(bootp_so, &sopt);
627 	if (error != 0)
628 		goto out;
629 
630 	/*
631 	 * Bind the local endpoint to a bootp client port.
632 	 */
633 	sin = &dst;
634 	clear_sinaddr(sin);
635 	sin->sin_port = htons(IPPORT_BOOTPC);
636 	error = sobind(bootp_so, (struct sockaddr *)sin, td);
637 	if (error != 0) {
638 		printf("bind failed\n");
639 		goto out;
640 	}
641 
642 	/*
643 	 * Setup socket address for the server.
644 	 */
645 	sin = &dst;
646 	clear_sinaddr(sin);
647 	sin->sin_addr.s_addr = INADDR_BROADCAST;
648 	sin->sin_port = htons(IPPORT_BOOTPS);
649 
650 	/*
651 	 * Send it, repeatedly, until a reply is received,
652 	 * but delay each re-send by an increasing amount.
653 	 * If the delay hits the maximum, start complaining.
654 	 */
655 	timo = 0;
656 	rtimo = 0;
657 	for (;;) {
658 
659 		outstanding = 0;
660 		gotrootpath = 0;
661 
662 		STAILQ_FOREACH(ifctx, &gctx->interfaces, next) {
663 			if (bootpc_ifctx_isresolved(ifctx) != 0 &&
664 			    bootpc_tag(&gctx->tmptag, &ifctx->reply,
665 				       ifctx->replylen,
666 				       TAG_ROOT) != NULL)
667 				gotrootpath = 1;
668 		}
669 
670 		STAILQ_FOREACH(ifctx, &gctx->interfaces, next) {
671 			struct in_aliasreq *ifra = &ifctx->iareq;
672 			sin = (struct sockaddr_in *)&ifra->ifra_mask;
673 
674 			ifctx->outstanding = 0;
675 			if (bootpc_ifctx_isresolved(ifctx)  != 0 &&
676 			    gotrootpath != 0) {
677 				continue;
678 			}
679 			if (bootpc_ifctx_isfailed(ifctx) != 0)
680 				continue;
681 
682 			outstanding++;
683 			ifctx->outstanding = 1;
684 
685 			/* Proceed to next step in DHCP negotiation */
686 			if ((ifctx->state == IF_DHCP_OFFERED &&
687 			     ifctx->dhcpquerytype != DHCP_REQUEST) ||
688 			    (ifctx->state == IF_DHCP_UNRESOLVED &&
689 			     ifctx->dhcpquerytype != DHCP_DISCOVER) ||
690 			    (ifctx->state == IF_BOOTP_UNRESOLVED &&
691 			     ifctx->dhcpquerytype != DHCP_NOMSG)) {
692 				ifctx->sentmsg = 0;
693 				bootpc_compose_query(ifctx, td);
694 			}
695 
696 			/* Send BOOTP request (or re-send). */
697 
698 			if (ifctx->sentmsg == 0) {
699 				switch(ifctx->dhcpquerytype) {
700 				case DHCP_DISCOVER:
701 					s = "DHCP Discover";
702 					break;
703 				case DHCP_REQUEST:
704 					s = "DHCP Request";
705 					break;
706 				case DHCP_NOMSG:
707 				default:
708 					s = "BOOTP Query";
709 					break;
710 				}
711 				printf("Sending %s packet from "
712 				       "interface %s (%*D)\n",
713 				       s,
714 				       ifctx->ireq.ifr_name,
715 				       ifctx->sdl->sdl_alen,
716 				       (unsigned char *) LLADDR(ifctx->sdl),
717 				       ":");
718 				ifctx->sentmsg = 1;
719 			}
720 
721 			aio.iov_base = (caddr_t) &ifctx->call;
722 			aio.iov_len = sizeof(ifctx->call);
723 
724 			auio.uio_iov = &aio;
725 			auio.uio_iovcnt = 1;
726 			auio.uio_segflg = UIO_SYSSPACE;
727 			auio.uio_rw = UIO_WRITE;
728 			auio.uio_offset = 0;
729 			auio.uio_resid = sizeof(ifctx->call);
730 			auio.uio_td = td;
731 
732 			/* Set netmask to 0.0.0.0 */
733 			clear_sinaddr(sin);
734 			error = ifioctl(bootp_so, SIOCAIFADDR, (caddr_t)ifra,
735 			    td);
736 			if (error != 0)
737 				panic("%s: SIOCAIFADDR, error=%d", __func__,
738 				    error);
739 
740 			error = sosend(bootp_so, (struct sockaddr *) &dst,
741 				       &auio, NULL, NULL, 0, td);
742 			if (error != 0)
743 				printf("%s: sosend: %d state %08x\n", __func__,
744 				    error, (int )bootp_so->so_state);
745 
746 			/* Set netmask to 255.0.0.0 */
747 			sin->sin_addr.s_addr = htonl(IN_CLASSA_NET);
748 			error = ifioctl(bootp_so, SIOCAIFADDR, (caddr_t)ifra,
749 			    td);
750 			if (error != 0)
751 				panic("%s: SIOCAIFADDR, error=%d", __func__,
752 				    error);
753 		}
754 
755 		if (outstanding == 0 &&
756 		    (rtimo == 0 || time_second >= rtimo)) {
757 			error = 0;
758 			goto out;
759 		}
760 
761 		/* Determine new timeout. */
762 		if (timo < MAX_RESEND_DELAY)
763 			timo++;
764 		else {
765 			printf("DHCP/BOOTP timeout for server ");
766 			print_sin_addr(&dst);
767 			printf("\n");
768 		}
769 
770 		/*
771 		 * Wait for up to timo seconds for a reply.
772 		 * The socket receive timeout was set to 1 second.
773 		 */
774 		atimo = timo + time_second;
775 		while (time_second < atimo) {
776 			aio.iov_base = (caddr_t) &gctx->reply;
777 			aio.iov_len = sizeof(gctx->reply);
778 
779 			auio.uio_iov = &aio;
780 			auio.uio_iovcnt = 1;
781 			auio.uio_segflg = UIO_SYSSPACE;
782 			auio.uio_rw = UIO_READ;
783 			auio.uio_offset = 0;
784 			auio.uio_resid = sizeof(gctx->reply);
785 			auio.uio_td = td;
786 
787 			rcvflg = 0;
788 			error = soreceive(bootp_so, NULL, &auio,
789 					  NULL, NULL, &rcvflg);
790 			gctx->secs = time_second - gctx->starttime;
791 			STAILQ_FOREACH(ifctx, &gctx->interfaces, next) {
792 				if (bootpc_ifctx_isresolved(ifctx) != 0 ||
793 				    bootpc_ifctx_isfailed(ifctx) != 0)
794 					continue;
795 
796 				ifctx->call.secs = htons(gctx->secs);
797 			}
798 			if (error == EWOULDBLOCK)
799 				continue;
800 			if (error != 0)
801 				goto out;
802 			len = sizeof(gctx->reply) - auio.uio_resid;
803 
804 			/* Do we have the required number of bytes ? */
805 			if (len < BOOTP_MIN_LEN)
806 				continue;
807 			gctx->replylen = len;
808 
809 			/* Is it a reply? */
810 			if (gctx->reply.op != BOOTP_REPLY)
811 				continue;
812 
813 			/* Is this an answer to our query */
814 			STAILQ_FOREACH(ifctx, &gctx->interfaces, next) {
815 				if (gctx->reply.xid != ifctx->call.xid)
816 					continue;
817 
818 				/* Same HW address size ? */
819 				if (gctx->reply.hlen != ifctx->call.hlen)
820 					continue;
821 
822 				/* Correct HW address ? */
823 				if (bcmp(gctx->reply.chaddr,
824 					 ifctx->call.chaddr,
825 					 ifctx->call.hlen) != 0)
826 					continue;
827 
828 				break;
829 			}
830 
831 			if (ifctx != NULL) {
832 				s =  bootpc_tag(&gctx->tmptag,
833 						&gctx->reply,
834 						gctx->replylen,
835 						TAG_DHCP_MSGTYPE);
836 				if (s != NULL) {
837 					switch (*s) {
838 					case DHCP_OFFER:
839 						s = "DHCP Offer";
840 						break;
841 					case DHCP_ACK:
842 						s = "DHCP Ack";
843 						break;
844 					default:
845 						s = "DHCP (unexpected)";
846 						break;
847 					}
848 				} else
849 					s = "BOOTP Reply";
850 
851 				printf("Received %s packet"
852 				       " on %s from ",
853 				       s,
854 				       ifctx->ireq.ifr_name);
855 				print_in_addr(gctx->reply.siaddr);
856 				if (gctx->reply.giaddr.s_addr !=
857 				    htonl(INADDR_ANY)) {
858 					printf(" via ");
859 					print_in_addr(gctx->reply.giaddr);
860 				}
861 				if (bootpc_received(gctx, ifctx) != 0) {
862 					printf(" (accepted)");
863 					if (ifctx->outstanding) {
864 						ifctx->outstanding = 0;
865 						outstanding--;
866 					}
867 					/* Network settle delay */
868 					if (outstanding == 0)
869 						atimo = time_second +
870 							BOOTP_SETTLE_DELAY;
871 				} else
872 					printf(" (ignored)");
873 				if (ifctx->gotrootpath ||
874 				    gctx->any_root_overrides) {
875 					gotrootpath = 1;
876 					rtimo = time_second +
877 						BOOTP_SETTLE_DELAY;
878 					if (ifctx->gotrootpath)
879 						printf(" (got root path)");
880 				}
881 				printf("\n");
882 			}
883 		} /* while secs */
884 #ifdef BOOTP_TIMEOUT
885 		if (gctx->secs > BOOTP_TIMEOUT && BOOTP_TIMEOUT > 0)
886 			break;
887 #endif
888 		/* Force a retry if halfway in DHCP negotiation */
889 		retry = 0;
890 		STAILQ_FOREACH(ifctx, &gctx->interfaces, next)
891 			if (ifctx->state == IF_DHCP_OFFERED) {
892 				if (ifctx->dhcpquerytype == DHCP_DISCOVER)
893 					retry = 1;
894 				else
895 					ifctx->state = IF_DHCP_UNRESOLVED;
896 			}
897 
898 		if (retry != 0)
899 			continue;
900 
901 		if (gotrootpath != 0) {
902 			gctx->gotrootpath = gotrootpath;
903 			if (rtimo != 0 && time_second >= rtimo)
904 				break;
905 		}
906 	} /* forever send/receive */
907 
908 	/*
909 	 * XXX: These are errors of varying seriousness being silently
910 	 * ignored
911 	 */
912 
913 	STAILQ_FOREACH(ifctx, &gctx->interfaces, next)
914 		if (bootpc_ifctx_isresolved(ifctx) == 0) {
915 			printf("%s timeout for interface %s\n",
916 			       ifctx->dhcpquerytype != DHCP_NOMSG ?
917 			       "DHCP" : "BOOTP",
918 			       ifctx->ireq.ifr_name);
919 		}
920 
921 	if (gctx->gotrootpath != 0) {
922 #if 0
923 		printf("Got a root path, ignoring remaining timeout\n");
924 #endif
925 		error = 0;
926 		goto out;
927 	}
928 #ifndef BOOTP_NFSROOT
929 	STAILQ_FOREACH(ifctx, &gctx->interfaces, next)
930 		if (bootpc_ifctx_isresolved(ifctx) != 0) {
931 			error = 0;
932 			goto out;
933 		}
934 #endif
935 	error = ETIMEDOUT;
936 
937 out:
938 	return (error);
939 }
940 
941 static void
bootpc_fakeup_interface(struct bootpc_ifcontext * ifctx,struct thread * td)942 bootpc_fakeup_interface(struct bootpc_ifcontext *ifctx, struct thread *td)
943 {
944 	struct ifreq *ifr;
945 	struct in_aliasreq *ifra;
946 	struct sockaddr_in *sin;
947 	int error;
948 
949 	ifr = &ifctx->ireq;
950 	ifra = &ifctx->iareq;
951 
952 	/*
953 	 * Bring up the interface.
954 	 *
955 	 * Get the old interface flags and or IFF_UP into them; if
956 	 * IFF_UP set blindly, interface selection can be clobbered.
957 	 */
958 	error = ifioctl(bootp_so, SIOCGIFFLAGS, (caddr_t)ifr, td);
959 	if (error != 0)
960 		panic("%s: SIOCGIFFLAGS, error=%d", __func__, error);
961 	ifr->ifr_flags |= IFF_UP;
962 	error = ifioctl(bootp_so, SIOCSIFFLAGS, (caddr_t)ifr, td);
963 	if (error != 0)
964 		panic("%s: SIOCSIFFLAGS, error=%d", __func__, error);
965 
966 	/*
967 	 * Do enough of ifconfig(8) so that the chosen interface
968 	 * can talk to the servers. Set address to 0.0.0.0/8 and
969 	 * broadcast address to local broadcast.
970 	 */
971 	sin = (struct sockaddr_in *)&ifra->ifra_addr;
972 	clear_sinaddr(sin);
973 	sin = (struct sockaddr_in *)&ifra->ifra_mask;
974 	clear_sinaddr(sin);
975 	sin->sin_addr.s_addr = htonl(IN_CLASSA_NET);
976 	sin = (struct sockaddr_in *)&ifra->ifra_broadaddr;
977 	clear_sinaddr(sin);
978 	sin->sin_addr.s_addr = htonl(INADDR_BROADCAST);
979 	error = ifioctl(bootp_so, SIOCAIFADDR, (caddr_t)ifra, td);
980 	if (error != 0)
981 		panic("%s: SIOCAIFADDR, error=%d", __func__, error);
982 }
983 
984 static void
bootpc_shutdown_interface(struct bootpc_ifcontext * ifctx,struct thread * td)985 bootpc_shutdown_interface(struct bootpc_ifcontext *ifctx, struct thread *td)
986 {
987 	struct ifreq *ifr;
988 	struct sockaddr_in *sin;
989 	int error;
990 
991 	ifr = &ifctx->ireq;
992 
993 	printf("Shutdown interface %s\n", ifctx->ireq.ifr_name);
994 	error = ifioctl(bootp_so, SIOCGIFFLAGS, (caddr_t)ifr, td);
995 	if (error != 0)
996 		panic("%s: SIOCGIFFLAGS, error=%d", __func__, error);
997 	ifr->ifr_flags &= ~IFF_UP;
998 	error = ifioctl(bootp_so, SIOCSIFFLAGS, (caddr_t)ifr, td);
999 	if (error != 0)
1000 		panic("%s: SIOCSIFFLAGS, error=%d", __func__, error);
1001 
1002 	sin = (struct sockaddr_in *) &ifr->ifr_addr;
1003 	clear_sinaddr(sin);
1004 	error = ifioctl(bootp_so, SIOCDIFADDR, (caddr_t) ifr, td);
1005 	if (error != 0)
1006 		panic("%s: SIOCDIFADDR, error=%d", __func__, error);
1007 }
1008 
1009 static int
bootpc_adjust_interface(struct bootpc_ifcontext * ifctx,struct bootpc_globalcontext * gctx,struct thread * td)1010 bootpc_adjust_interface(struct bootpc_ifcontext *ifctx,
1011     struct bootpc_globalcontext *gctx, struct thread *td)
1012 {
1013 	int error;
1014 	struct sockaddr_in defdst;
1015 	struct sockaddr_in defmask;
1016 	struct sockaddr_in *sin;
1017 	struct ifreq *ifr;
1018 	struct in_aliasreq *ifra;
1019 	struct sockaddr_in *myaddr;
1020 	struct sockaddr_in *netmask;
1021 	struct sockaddr_in *gw;
1022 
1023 	ifr = &ifctx->ireq;
1024 	ifra = &ifctx->iareq;
1025 	myaddr = &ifctx->myaddr;
1026 	netmask = &ifctx->netmask;
1027 	gw = &ifctx->gw;
1028 
1029 	if (bootpc_ifctx_isresolved(ifctx) == 0) {
1030 		/* Shutdown interfaces where BOOTP failed */
1031 		bootpc_shutdown_interface(ifctx, td);
1032 		return (0);
1033 	}
1034 
1035 	printf("Adjusted interface %s\n", ifctx->ireq.ifr_name);
1036 	/*
1037 	 * Do enough of ifconfig(8) so that the chosen interface
1038 	 * can talk to the servers.  (just set the address)
1039 	 */
1040 	sin = (struct sockaddr_in *) &ifr->ifr_addr;
1041 	clear_sinaddr(sin);
1042 	error = ifioctl(bootp_so, SIOCDIFADDR, (caddr_t) ifr, td);
1043 	if (error != 0)
1044 		panic("%s: SIOCDIFADDR, error=%d", __func__, error);
1045 
1046 	bcopy(myaddr, &ifra->ifra_addr, sizeof(*myaddr));
1047 	bcopy(netmask, &ifra->ifra_mask, sizeof(*netmask));
1048 	clear_sinaddr(&ifra->ifra_broadaddr);
1049 	ifra->ifra_broadaddr.sin_addr.s_addr = myaddr->sin_addr.s_addr |
1050 	    ~netmask->sin_addr.s_addr;
1051 
1052 	error = ifioctl(bootp_so, SIOCAIFADDR, (caddr_t)ifra, td);
1053 	if (error != 0)
1054 		panic("%s: SIOCAIFADDR, error=%d", __func__, error);
1055 
1056 	/* Add new default route */
1057 
1058 	if (ifctx->gotgw != 0 || gctx->gotgw == 0) {
1059 		clear_sinaddr(&defdst);
1060 		clear_sinaddr(&defmask);
1061 		/* XXX MRT just table 0 */
1062 		error = rtrequest_fib(RTM_ADD,
1063 		    (struct sockaddr *) &defdst, (struct sockaddr *) gw,
1064 		    (struct sockaddr *) &defmask,
1065 		    (RTF_UP | RTF_GATEWAY | RTF_STATIC), NULL, RT_DEFAULT_FIB);
1066 		if (error != 0) {
1067 			printf("%s: RTM_ADD, error=%d\n", __func__, error);
1068 			return (error);
1069 		}
1070 	}
1071 
1072 	return (0);
1073 }
1074 
1075 static int
setfs(struct sockaddr_in * addr,char * path,char * p,const struct in_addr * siaddr)1076 setfs(struct sockaddr_in *addr, char *path, char *p,
1077     const struct in_addr *siaddr)
1078 {
1079 
1080 	if (getip(&p, &addr->sin_addr) == 0) {
1081 		if (siaddr != NULL && *p == '/')
1082 			bcopy(siaddr, &addr->sin_addr, sizeof(struct in_addr));
1083 		else
1084 			return 0;
1085 	} else {
1086 		if (*p != ':')
1087 			return 0;
1088 		p++;
1089 	}
1090 
1091 	addr->sin_len = sizeof(struct sockaddr_in);
1092 	addr->sin_family = AF_INET;
1093 
1094 	strlcpy(path, p, MNAMELEN);
1095 	return 1;
1096 }
1097 
1098 static int
getip(char ** ptr,struct in_addr * addr)1099 getip(char **ptr, struct in_addr *addr)
1100 {
1101 	char *p;
1102 	unsigned int ip;
1103 	int val;
1104 
1105 	p = *ptr;
1106 	ip = 0;
1107 	if (((val = getdec(&p)) < 0) || (val > 255))
1108 		return 0;
1109 	ip = val << 24;
1110 	if (*p != '.')
1111 		return 0;
1112 	p++;
1113 	if (((val = getdec(&p)) < 0) || (val > 255))
1114 		return 0;
1115 	ip |= (val << 16);
1116 	if (*p != '.')
1117 		return 0;
1118 	p++;
1119 	if (((val = getdec(&p)) < 0) || (val > 255))
1120 		return 0;
1121 	ip |= (val << 8);
1122 	if (*p != '.')
1123 		return 0;
1124 	p++;
1125 	if (((val = getdec(&p)) < 0) || (val > 255))
1126 		return 0;
1127 	ip |= val;
1128 
1129 	addr->s_addr = htonl(ip);
1130 	*ptr = p;
1131 	return 1;
1132 }
1133 
1134 static int
getdec(char ** ptr)1135 getdec(char **ptr)
1136 {
1137 	char *p;
1138 	int ret;
1139 
1140 	p = *ptr;
1141 	ret = 0;
1142 	if ((*p < '0') || (*p > '9'))
1143 		return -1;
1144 	while ((*p >= '0') && (*p <= '9')) {
1145 		ret = ret * 10 + (*p - '0');
1146 		p++;
1147 	}
1148 	*ptr = p;
1149 	return ret;
1150 }
1151 
1152 static void
mountopts(struct nfs_args * args,char * p)1153 mountopts(struct nfs_args *args, char *p)
1154 {
1155 	args->version = NFS_ARGSVERSION;
1156 	args->rsize = BOOTP_BLOCKSIZE;
1157 	args->wsize = BOOTP_BLOCKSIZE;
1158 	args->flags = NFSMNT_RSIZE | NFSMNT_WSIZE | NFSMNT_RESVPORT;
1159 	args->sotype = SOCK_DGRAM;
1160 	if (p != NULL)
1161 		nfs_parse_options(p, args);
1162 }
1163 
1164 static int
xdr_opaque_decode(struct mbuf ** mptr,u_char * buf,int len)1165 xdr_opaque_decode(struct mbuf **mptr, u_char *buf, int len)
1166 {
1167 	struct mbuf *m;
1168 	int alignedlen;
1169 
1170 	m = *mptr;
1171 	alignedlen = ( len + 3 ) & ~3;
1172 
1173 	if (m->m_len < alignedlen) {
1174 		m = m_pullup(m, alignedlen);
1175 		if (m == NULL) {
1176 			*mptr = NULL;
1177 			return EBADRPC;
1178 		}
1179 	}
1180 	bcopy(mtod(m, u_char *), buf, len);
1181 	m_adj(m, alignedlen);
1182 	*mptr = m;
1183 	return 0;
1184 }
1185 
1186 static int
xdr_int_decode(struct mbuf ** mptr,int * iptr)1187 xdr_int_decode(struct mbuf **mptr, int *iptr)
1188 {
1189 	u_int32_t i;
1190 
1191 	if (xdr_opaque_decode(mptr, (u_char *) &i, sizeof(u_int32_t)) != 0)
1192 		return EBADRPC;
1193 	*iptr = fxdr_unsigned(u_int32_t, i);
1194 	return 0;
1195 }
1196 
1197 static void
print_sin_addr(struct sockaddr_in * sin)1198 print_sin_addr(struct sockaddr_in *sin)
1199 {
1200 
1201 	print_in_addr(sin->sin_addr);
1202 }
1203 
1204 static void
print_in_addr(struct in_addr addr)1205 print_in_addr(struct in_addr addr)
1206 {
1207 	unsigned int ip;
1208 
1209 	ip = ntohl(addr.s_addr);
1210 	printf("%d.%d.%d.%d",
1211 	       ip >> 24, (ip >> 16) & 255, (ip >> 8) & 255, ip & 255);
1212 }
1213 
1214 static void
bootpc_compose_query(struct bootpc_ifcontext * ifctx,struct thread * td)1215 bootpc_compose_query(struct bootpc_ifcontext *ifctx, struct thread *td)
1216 {
1217 	unsigned char *vendp;
1218 	unsigned char vendor_client[64];
1219 	uint32_t leasetime;
1220 	uint8_t vendor_client_len;
1221 
1222 	ifctx->gotrootpath = 0;
1223 
1224 	bzero((caddr_t) &ifctx->call, sizeof(ifctx->call));
1225 
1226 	/* bootpc part */
1227 	ifctx->call.op = BOOTP_REQUEST; 	/* BOOTREQUEST */
1228 	ifctx->call.htype = 1;			/* 10mb ethernet */
1229 	ifctx->call.hlen = ifctx->sdl->sdl_alen;/* Hardware address length */
1230 	ifctx->call.hops = 0;
1231 	if (bootpc_ifctx_isunresolved(ifctx) != 0)
1232 		ifctx->xid++;
1233 	ifctx->call.xid = txdr_unsigned(ifctx->xid);
1234 	bcopy(LLADDR(ifctx->sdl), &ifctx->call.chaddr, ifctx->sdl->sdl_alen);
1235 
1236 	vendp = ifctx->call.vend;
1237 	*vendp++ = 99;		/* RFC1048 cookie */
1238 	*vendp++ = 130;
1239 	*vendp++ = 83;
1240 	*vendp++ = 99;
1241 	*vendp++ = TAG_MAXMSGSIZE;
1242 	*vendp++ = 2;
1243 	*vendp++ = (sizeof(struct bootp_packet) >> 8) & 255;
1244 	*vendp++ = sizeof(struct bootp_packet) & 255;
1245 
1246 	snprintf(vendor_client, sizeof(vendor_client), "%s:%s:%s",
1247 		ostype, MACHINE, osrelease);
1248 	vendor_client_len = strlen(vendor_client);
1249 	*vendp++ = TAG_VENDOR_INDENTIFIER;
1250 	*vendp++ = vendor_client_len;
1251 	memcpy(vendp, vendor_client, vendor_client_len);
1252 	vendp += vendor_client_len;
1253 	ifctx->dhcpquerytype = DHCP_NOMSG;
1254 	switch (ifctx->state) {
1255 	case IF_DHCP_UNRESOLVED:
1256 		*vendp++ = TAG_DHCP_MSGTYPE;
1257 		*vendp++ = 1;
1258 		*vendp++ = DHCP_DISCOVER;
1259 		ifctx->dhcpquerytype = DHCP_DISCOVER;
1260 		ifctx->gotdhcpserver = 0;
1261 		break;
1262 	case IF_DHCP_OFFERED:
1263 		*vendp++ = TAG_DHCP_MSGTYPE;
1264 		*vendp++ = 1;
1265 		*vendp++ = DHCP_REQUEST;
1266 		ifctx->dhcpquerytype = DHCP_REQUEST;
1267 		*vendp++ = TAG_DHCP_REQ_ADDR;
1268 		*vendp++ = 4;
1269 		memcpy(vendp, &ifctx->reply.yiaddr, 4);
1270 		vendp += 4;
1271 		if (ifctx->gotdhcpserver != 0) {
1272 			*vendp++ = TAG_DHCP_SERVERID;
1273 			*vendp++ = 4;
1274 			memcpy(vendp, &ifctx->dhcpserver, 4);
1275 			vendp += 4;
1276 		}
1277 		*vendp++ = TAG_DHCP_LEASETIME;
1278 		*vendp++ = 4;
1279 		leasetime = htonl(300);
1280 		memcpy(vendp, &leasetime, 4);
1281 		vendp += 4;
1282 		break;
1283 	default:
1284 		break;
1285 	}
1286 	*vendp = TAG_END;
1287 
1288 	ifctx->call.secs = 0;
1289 	ifctx->call.flags = htons(0x8000); /* We need a broadcast answer */
1290 }
1291 
1292 static int
bootpc_hascookie(struct bootp_packet * bp)1293 bootpc_hascookie(struct bootp_packet *bp)
1294 {
1295 
1296 	return (bp->vend[0] == 99 && bp->vend[1] == 130 &&
1297 		bp->vend[2] == 83 && bp->vend[3] == 99);
1298 }
1299 
1300 static void
bootpc_tag_helper(struct bootpc_tagcontext * tctx,unsigned char * start,int len,int tag)1301 bootpc_tag_helper(struct bootpc_tagcontext *tctx,
1302     unsigned char *start, int len, int tag)
1303 {
1304 	unsigned char *j;
1305 	unsigned char *ej;
1306 	unsigned char code;
1307 
1308 	if (tctx->badtag != 0 || tctx->badopt != 0)
1309 		return;
1310 
1311 	j = start;
1312 	ej = j + len;
1313 
1314 	while (j < ej) {
1315 		code = *j++;
1316 		if (code == TAG_PAD)
1317 			continue;
1318 		if (code == TAG_END)
1319 			return;
1320 		if (j >= ej || j + *j + 1 > ej) {
1321 			tctx->badopt = 1;
1322 			return;
1323 		}
1324 		len = *j++;
1325 		if (code == tag) {
1326 			if (tctx->taglen + len > TAG_MAXLEN) {
1327 				tctx->badtag = 1;
1328 				return;
1329 			}
1330 			tctx->foundopt = 1;
1331 			if (len > 0)
1332 				memcpy(tctx->buf + tctx->taglen,
1333 				       j, len);
1334 			tctx->taglen += len;
1335 		}
1336 		if (code == TAG_OVERLOAD)
1337 			tctx->overload = *j;
1338 
1339 		j += len;
1340 	}
1341 }
1342 
1343 static unsigned char *
bootpc_tag(struct bootpc_tagcontext * tctx,struct bootp_packet * bp,int len,int tag)1344 bootpc_tag(struct bootpc_tagcontext *tctx,
1345     struct bootp_packet *bp, int len, int tag)
1346 {
1347 	tctx->overload = 0;
1348 	tctx->badopt = 0;
1349 	tctx->badtag = 0;
1350 	tctx->foundopt = 0;
1351 	tctx->taglen = 0;
1352 
1353 	if (bootpc_hascookie(bp) == 0)
1354 		return NULL;
1355 
1356 	bootpc_tag_helper(tctx, &bp->vend[4],
1357 			  (unsigned char *) bp + len - &bp->vend[4], tag);
1358 
1359 	if ((tctx->overload & OVERLOAD_FILE) != 0)
1360 		bootpc_tag_helper(tctx,
1361 				  (unsigned char *) bp->file,
1362 				  sizeof(bp->file),
1363 				  tag);
1364 	if ((tctx->overload & OVERLOAD_SNAME) != 0)
1365 		bootpc_tag_helper(tctx,
1366 				  (unsigned char *) bp->sname,
1367 				  sizeof(bp->sname),
1368 				  tag);
1369 
1370 	if (tctx->badopt != 0 || tctx->badtag != 0 || tctx->foundopt == 0)
1371 		return NULL;
1372 	tctx->buf[tctx->taglen] = '\0';
1373 	return tctx->buf;
1374 }
1375 
1376 static void
bootpc_decode_reply(struct nfsv3_diskless * nd,struct bootpc_ifcontext * ifctx,struct bootpc_globalcontext * gctx)1377 bootpc_decode_reply(struct nfsv3_diskless *nd, struct bootpc_ifcontext *ifctx,
1378     struct bootpc_globalcontext *gctx)
1379 {
1380 	char *p, *s;
1381 	unsigned int ip;
1382 
1383 	ifctx->gotgw = 0;
1384 	ifctx->gotnetmask = 0;
1385 
1386 	clear_sinaddr(&ifctx->myaddr);
1387 	clear_sinaddr(&ifctx->netmask);
1388 	clear_sinaddr(&ifctx->gw);
1389 
1390 	ifctx->myaddr.sin_addr = ifctx->reply.yiaddr;
1391 
1392 	ip = ntohl(ifctx->myaddr.sin_addr.s_addr);
1393 
1394 	printf("%s at ", ifctx->ireq.ifr_name);
1395 	print_sin_addr(&ifctx->myaddr);
1396 	printf(" server ");
1397 	print_in_addr(ifctx->reply.siaddr);
1398 
1399 	ifctx->gw.sin_addr = ifctx->reply.giaddr;
1400 	if (ifctx->reply.giaddr.s_addr != htonl(INADDR_ANY)) {
1401 		printf(" via gateway ");
1402 		print_in_addr(ifctx->reply.giaddr);
1403 	}
1404 
1405 	/* This call used for the side effect (overload flag) */
1406 	(void) bootpc_tag(&gctx->tmptag,
1407 			  &ifctx->reply, ifctx->replylen, TAG_END);
1408 
1409 	if ((gctx->tmptag.overload & OVERLOAD_SNAME) == 0)
1410 		if (ifctx->reply.sname[0] != '\0')
1411 			printf(" server name %s", ifctx->reply.sname);
1412 	if ((gctx->tmptag.overload & OVERLOAD_FILE) == 0)
1413 		if (ifctx->reply.file[0] != '\0')
1414 			printf(" boot file %s", ifctx->reply.file);
1415 
1416 	printf("\n");
1417 
1418 	p = bootpc_tag(&gctx->tag, &ifctx->reply, ifctx->replylen,
1419 		       TAG_SUBNETMASK);
1420 	if (p != NULL) {
1421 		if (gctx->tag.taglen != 4)
1422 			panic("bootpc: subnet mask len is %d",
1423 			      gctx->tag.taglen);
1424 		bcopy(p, &ifctx->netmask.sin_addr, 4);
1425 		ifctx->gotnetmask = 1;
1426 		printf("subnet mask ");
1427 		print_sin_addr(&ifctx->netmask);
1428 		printf(" ");
1429 	}
1430 
1431 	p = bootpc_tag(&gctx->tag, &ifctx->reply, ifctx->replylen,
1432 		       TAG_ROUTERS);
1433 	if (p != NULL) {
1434 		/* Routers */
1435 		if (gctx->tag.taglen % 4)
1436 			panic("bootpc: Router Len is %d", gctx->tag.taglen);
1437 		if (gctx->tag.taglen > 0) {
1438 			bcopy(p, &ifctx->gw.sin_addr, 4);
1439 			printf("router ");
1440 			print_sin_addr(&ifctx->gw);
1441 			printf(" ");
1442 			ifctx->gotgw = 1;
1443 			gctx->gotgw = 1;
1444 		}
1445 	}
1446 
1447 	/*
1448 	 * Choose a root filesystem.  If a value is forced in the environment
1449 	 * and it contains "nfs:", use it unconditionally.  Otherwise, if the
1450 	 * kernel is compiled with the ROOTDEVNAME option, then use it if:
1451 	 *  - The server doesn't provide a pathname.
1452 	 *  - The boothowto flags include RB_DFLTROOT (user said to override
1453 	 *    the server value).
1454 	 */
1455 	p = NULL;
1456 	if ((s = getenv("vfs.root.mountfrom")) != NULL) {
1457 		if ((p = strstr(s, "nfs:")) != NULL)
1458 			p = strdup(p + 4, M_TEMP);
1459 		freeenv(s);
1460 	}
1461 	if (p == NULL) {
1462 		p = bootpc_tag(&gctx->tag, &ifctx->reply, ifctx->replylen,
1463 		       TAG_ROOT);
1464 	}
1465 #ifdef ROOTDEVNAME
1466 	if ((p == NULL || (boothowto & RB_DFLTROOT) != 0) &&
1467 	    (p = strstr(ROOTDEVNAME, "nfs:")) != NULL) {
1468 		p += 4;
1469 	}
1470 #endif
1471 	if (p != NULL) {
1472 		if (gctx->setrootfs != NULL) {
1473 			printf("rootfs %s (ignored) ", p);
1474 		} else 	if (setfs(&nd->root_saddr,
1475 				  nd->root_hostnam, p, &ifctx->reply.siaddr)) {
1476 			if (*p == '/') {
1477 				printf("root_server ");
1478 				print_sin_addr(&nd->root_saddr);
1479 				printf(" ");
1480 			}
1481 			printf("rootfs %s ", p);
1482 			gctx->gotrootpath = 1;
1483 			ifctx->gotrootpath = 1;
1484 			gctx->setrootfs = ifctx;
1485 
1486 			p = bootpc_tag(&gctx->tag, &ifctx->reply,
1487 				       ifctx->replylen,
1488 				       TAG_ROOTOPTS);
1489 			if (p != NULL) {
1490 				mountopts(&nd->root_args, p);
1491 				printf("rootopts %s ", p);
1492 			}
1493 		} else
1494 			panic("Failed to set rootfs to %s", p);
1495 	}
1496 
1497 	p = bootpc_tag(&gctx->tag, &ifctx->reply, ifctx->replylen,
1498 		       TAG_HOSTNAME);
1499 	if (p != NULL) {
1500 		if (gctx->tag.taglen >= MAXHOSTNAMELEN)
1501 			panic("bootpc: hostname >= %d bytes",
1502 			      MAXHOSTNAMELEN);
1503 		if (gctx->sethostname != NULL) {
1504 			printf("hostname %s (ignored) ", p);
1505 		} else {
1506 			strcpy(nd->my_hostnam, p);
1507 			mtx_lock(&prison0.pr_mtx);
1508 			strcpy(prison0.pr_hostname, p);
1509 			mtx_unlock(&prison0.pr_mtx);
1510 			printf("hostname %s ", p);
1511 			gctx->sethostname = ifctx;
1512 		}
1513 	}
1514 	p = bootpc_tag(&gctx->tag, &ifctx->reply, ifctx->replylen,
1515 			TAG_COOKIE);
1516 	if (p != NULL) {        /* store in a sysctl variable */
1517 		int i, l = sizeof(bootp_cookie) - 1;
1518 		for (i = 0; i < l && p[i] != '\0'; i++)
1519 			bootp_cookie[i] = p[i];
1520 		p[i] = '\0';
1521 	}
1522 
1523 
1524 	printf("\n");
1525 
1526 	if (ifctx->gotnetmask == 0) {
1527 		if (IN_CLASSA(ntohl(ifctx->myaddr.sin_addr.s_addr)))
1528 			ifctx->netmask.sin_addr.s_addr = htonl(IN_CLASSA_NET);
1529 		else if (IN_CLASSB(ntohl(ifctx->myaddr.sin_addr.s_addr)))
1530 			ifctx->netmask.sin_addr.s_addr = htonl(IN_CLASSB_NET);
1531 		else
1532 			ifctx->netmask.sin_addr.s_addr = htonl(IN_CLASSC_NET);
1533 	}
1534 	if (ifctx->gotgw == 0) {
1535 		/* Use proxyarp */
1536 		ifctx->gw.sin_addr.s_addr = ifctx->myaddr.sin_addr.s_addr;
1537 	}
1538 }
1539 
1540 void
bootpc_init(void)1541 bootpc_init(void)
1542 {
1543 	struct bootpc_ifcontext *ifctx;		/* Interface BOOTP contexts */
1544 	struct bootpc_globalcontext *gctx; 	/* Global BOOTP context */
1545 	struct ifnet *ifp;
1546 	struct sockaddr_dl *sdl;
1547 	struct ifaddr *ifa;
1548 	int error;
1549 #ifndef BOOTP_WIRED_TO
1550 	int ifcnt;
1551 #endif
1552 	struct nfsv3_diskless *nd;
1553 	struct thread *td;
1554 	int timeout;
1555 	int delay;
1556 
1557 	timeout = BOOTP_IFACE_WAIT_TIMEOUT * hz;
1558 	delay = hz / 10;
1559 
1560 	nd = &nfsv3_diskless;
1561 	td = curthread;
1562 
1563 	/*
1564 	 * If already filled in, don't touch it here
1565 	 */
1566 	if (nfs_diskless_valid != 0)
1567 		return;
1568 
1569 	gctx = malloc(sizeof(*gctx), M_TEMP, M_WAITOK | M_ZERO);
1570 	STAILQ_INIT(&gctx->interfaces);
1571 	gctx->xid = ~0xFFFF;
1572 	gctx->starttime = time_second;
1573 
1574 	/*
1575 	 * If ROOTDEVNAME is defined or vfs.root.mountfrom is set then we have
1576 	 * root-path overrides that can potentially let us boot even if we don't
1577 	 * get a root path from the server, so we can treat that as a non-error.
1578 	 */
1579 #ifdef ROOTDEVNAME
1580 	gctx->any_root_overrides = 1;
1581 #else
1582 	gctx->any_root_overrides = testenv("vfs.root.mountfrom");
1583 #endif
1584 
1585 	/*
1586 	 * Find a network interface.
1587 	 */
1588 	CURVNET_SET(TD_TO_VNET(td));
1589 #ifdef BOOTP_WIRED_TO
1590 	printf("%s: wired to interface '%s'\n", __func__,
1591 	       __XSTRING(BOOTP_WIRED_TO));
1592 	allocifctx(gctx);
1593 #else
1594 	/*
1595 	 * Preallocate interface context storage, if another interface
1596 	 * attaches and wins the race, it won't be eligible for bootp.
1597 	 */
1598 	ifcnt = 0;
1599 	IFNET_RLOCK();
1600 	TAILQ_FOREACH(ifp, &V_ifnet, if_link) {
1601 		if ((ifp->if_flags &
1602 		     (IFF_LOOPBACK | IFF_POINTOPOINT | IFF_BROADCAST)) !=
1603 		    IFF_BROADCAST)
1604 			continue;
1605 		switch (ifp->if_alloctype) {
1606 			case IFT_ETHER:
1607 			case IFT_FDDI:
1608 			case IFT_ISO88025:
1609 				break;
1610 			default:
1611 				continue;
1612 		}
1613 		ifcnt++;
1614 	}
1615 	IFNET_RUNLOCK();
1616 	if (ifcnt == 0)
1617 		panic("%s: no eligible interfaces", __func__);
1618 	for (; ifcnt > 0; ifcnt--)
1619 		allocifctx(gctx);
1620 #endif
1621 
1622 retry:
1623 	ifctx = STAILQ_FIRST(&gctx->interfaces);
1624 	IFNET_RLOCK();
1625 	TAILQ_FOREACH(ifp, &V_ifnet, if_link) {
1626 		if (ifctx == NULL)
1627 			break;
1628 #ifdef BOOTP_WIRED_TO
1629 		if (strcmp(ifp->if_xname, __XSTRING(BOOTP_WIRED_TO)) != 0)
1630 			continue;
1631 #else
1632 		if ((ifp->if_flags &
1633 		     (IFF_LOOPBACK | IFF_POINTOPOINT | IFF_BROADCAST)) !=
1634 		    IFF_BROADCAST)
1635 			continue;
1636 		switch (ifp->if_alloctype) {
1637 			case IFT_ETHER:
1638 			case IFT_FDDI:
1639 			case IFT_ISO88025:
1640 				break;
1641 			default:
1642 				continue;
1643 		}
1644 #endif
1645 		strlcpy(ifctx->ireq.ifr_name, ifp->if_xname,
1646 		    sizeof(ifctx->ireq.ifr_name));
1647 		ifctx->ifp = ifp;
1648 
1649 		/* Get HW address */
1650 		sdl = NULL;
1651 		TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link)
1652 			if (ifa->ifa_addr->sa_family == AF_LINK) {
1653 				sdl = (struct sockaddr_dl *)ifa->ifa_addr;
1654 				if (sdl->sdl_type == IFT_ETHER)
1655 					break;
1656 			}
1657 		if (sdl == NULL)
1658 			panic("bootpc: Unable to find HW address for %s",
1659 			    ifctx->ireq.ifr_name);
1660 		ifctx->sdl = sdl;
1661 
1662 		ifctx = STAILQ_NEXT(ifctx, next);
1663 	}
1664 	IFNET_RUNLOCK();
1665 	CURVNET_RESTORE();
1666 
1667 	if (STAILQ_EMPTY(&gctx->interfaces) ||
1668 	    STAILQ_FIRST(&gctx->interfaces)->ifp == NULL) {
1669 		if (timeout > 0) {
1670 			pause("bootpc", delay);
1671 			timeout -= delay;
1672 			goto retry;
1673 		}
1674 #ifdef BOOTP_WIRED_TO
1675 		panic("%s: Could not find interface specified "
1676 		      "by BOOTP_WIRED_TO: "
1677 		      __XSTRING(BOOTP_WIRED_TO), __func__);
1678 #else
1679 		panic("%s: no suitable interface", __func__);
1680 #endif
1681 	}
1682 
1683 	error = socreate(AF_INET, &bootp_so, SOCK_DGRAM, 0, td->td_ucred, td);
1684 	if (error != 0)
1685 		panic("%s: socreate, error=%d", __func__, error);
1686 
1687 	STAILQ_FOREACH(ifctx, &gctx->interfaces, next)
1688 		bootpc_fakeup_interface(ifctx, td);
1689 
1690 	STAILQ_FOREACH(ifctx, &gctx->interfaces, next)
1691 		bootpc_compose_query(ifctx, td);
1692 
1693 	error = bootpc_call(gctx, td);
1694 	if (error != 0) {
1695 		printf("BOOTP call failed\n");
1696 	}
1697 
1698 	mountopts(&nd->root_args, NULL);
1699 
1700 	STAILQ_FOREACH(ifctx, &gctx->interfaces, next)
1701 		if (bootpc_ifctx_isresolved(ifctx) != 0)
1702 			bootpc_decode_reply(nd, ifctx, gctx);
1703 
1704 #ifdef BOOTP_NFSROOT
1705 	if (gctx->gotrootpath == 0 && gctx->any_root_overrides == 0)
1706 		panic("bootpc: No root path offered");
1707 #endif
1708 
1709 	STAILQ_FOREACH(ifctx, &gctx->interfaces, next)
1710 		bootpc_adjust_interface(ifctx, gctx, td);
1711 
1712 	soclose(bootp_so);
1713 
1714 	STAILQ_FOREACH(ifctx, &gctx->interfaces, next)
1715 		if (ifctx->gotrootpath != 0)
1716 			break;
1717 	if (ifctx == NULL) {
1718 		STAILQ_FOREACH(ifctx, &gctx->interfaces, next)
1719 			if (bootpc_ifctx_isresolved(ifctx) != 0)
1720 				break;
1721 	}
1722 	if (ifctx == NULL)
1723 		goto out;
1724 
1725 	if (gctx->gotrootpath != 0) {
1726 
1727 		setenv("boot.netif.name", ifctx->ifp->if_xname);
1728 
1729 		error = md_mount(&nd->root_saddr, nd->root_hostnam,
1730 				 nd->root_fh, &nd->root_fhsize,
1731 				 &nd->root_args, td);
1732 		if (error != 0) {
1733 			if (gctx->any_root_overrides == 0)
1734 				panic("nfs_boot: mount root, error=%d", error);
1735 			else
1736 				goto out;
1737 		}
1738 		rootdevnames[0] = "nfs:";
1739 #ifdef NFSCLIENT
1740 		rootdevnames[1] = "oldnfs:";
1741 #endif
1742 		nfs_diskless_valid = 3;
1743 	}
1744 
1745 	strcpy(nd->myif.ifra_name, ifctx->ireq.ifr_name);
1746 	bcopy(&ifctx->myaddr, &nd->myif.ifra_addr, sizeof(ifctx->myaddr));
1747 	bcopy(&ifctx->myaddr, &nd->myif.ifra_broadaddr, sizeof(ifctx->myaddr));
1748 	((struct sockaddr_in *) &nd->myif.ifra_broadaddr)->sin_addr.s_addr =
1749 		ifctx->myaddr.sin_addr.s_addr |
1750 		~ ifctx->netmask.sin_addr.s_addr;
1751 	bcopy(&ifctx->netmask, &nd->myif.ifra_mask, sizeof(ifctx->netmask));
1752 
1753 out:
1754 	while((ifctx = STAILQ_FIRST(&gctx->interfaces)) != NULL) {
1755 		STAILQ_REMOVE_HEAD(&gctx->interfaces, next);
1756 		free(ifctx, M_TEMP);
1757 	}
1758 	free(gctx, M_TEMP);
1759 }
1760 
1761 /*
1762  * RPC: mountd/mount
1763  * Given a server pathname, get an NFS file handle.
1764  * Also, sets sin->sin_port to the NFS service port.
1765  */
1766 static int
md_mount(struct sockaddr_in * mdsin,char * path,u_char * fhp,int * fhsizep,struct nfs_args * args,struct thread * td)1767 md_mount(struct sockaddr_in *mdsin, char *path, u_char *fhp, int *fhsizep,
1768     struct nfs_args *args, struct thread *td)
1769 {
1770 	struct mbuf *m;
1771 	int error;
1772 	int authunixok;
1773 	int authcount;
1774 	int authver;
1775 
1776 #define	RPCPROG_MNT	100005
1777 #define	RPCMNT_VER1	1
1778 #define RPCMNT_VER3	3
1779 #define	RPCMNT_MOUNT	1
1780 #define	AUTH_SYS	1		/* unix style (uid, gids) */
1781 #define AUTH_UNIX	AUTH_SYS
1782 
1783 	/* XXX honor v2/v3 flags in args->flags? */
1784 #ifdef BOOTP_NFSV3
1785 	/* First try NFS v3 */
1786 	/* Get port number for MOUNTD. */
1787 	error = krpc_portmap(mdsin, RPCPROG_MNT, RPCMNT_VER3,
1788 			     &mdsin->sin_port, td);
1789 	if (error == 0) {
1790 		m = xdr_string_encode(path, strlen(path));
1791 
1792 		/* Do RPC to mountd. */
1793 		error = krpc_call(mdsin, RPCPROG_MNT, RPCMNT_VER3,
1794 				  RPCMNT_MOUNT, &m, NULL, td);
1795 	}
1796 	if (error == 0) {
1797 		args->flags |= NFSMNT_NFSV3;
1798 	} else {
1799 #endif
1800 		/* Fallback to NFS v2 */
1801 
1802 		/* Get port number for MOUNTD. */
1803 		error = krpc_portmap(mdsin, RPCPROG_MNT, RPCMNT_VER1,
1804 				     &mdsin->sin_port, td);
1805 		if (error != 0)
1806 			return error;
1807 
1808 		m = xdr_string_encode(path, strlen(path));
1809 
1810 		/* Do RPC to mountd. */
1811 		error = krpc_call(mdsin, RPCPROG_MNT, RPCMNT_VER1,
1812 				  RPCMNT_MOUNT, &m, NULL, td);
1813 		if (error != 0)
1814 			return error;	/* message already freed */
1815 
1816 #ifdef BOOTP_NFSV3
1817 	}
1818 #endif
1819 
1820 	if (xdr_int_decode(&m, &error) != 0 || error != 0)
1821 		goto bad;
1822 
1823 	if ((args->flags & NFSMNT_NFSV3) != 0) {
1824 		if (xdr_int_decode(&m, fhsizep) != 0 ||
1825 		    *fhsizep > NFSX_V3FHMAX ||
1826 		    *fhsizep <= 0)
1827 			goto bad;
1828 	} else
1829 		*fhsizep = NFSX_V2FH;
1830 
1831 	if (xdr_opaque_decode(&m, fhp, *fhsizep) != 0)
1832 		goto bad;
1833 
1834 	if (args->flags & NFSMNT_NFSV3) {
1835 		if (xdr_int_decode(&m, &authcount) != 0)
1836 			goto bad;
1837 		authunixok = 0;
1838 		if (authcount < 0 || authcount > 100)
1839 			goto bad;
1840 		while (authcount > 0) {
1841 			if (xdr_int_decode(&m, &authver) != 0)
1842 				goto bad;
1843 			if (authver == AUTH_UNIX)
1844 				authunixok = 1;
1845 			authcount--;
1846 		}
1847 		if (authunixok == 0)
1848 			goto bad;
1849 	}
1850 
1851 	/* Set port number for NFS use. */
1852 	error = krpc_portmap(mdsin, NFS_PROG,
1853 			     (args->flags &
1854 			      NFSMNT_NFSV3) ? NFS_VER3 : NFS_VER2,
1855 			     &mdsin->sin_port, td);
1856 
1857 	goto out;
1858 
1859 bad:
1860 	error = EBADRPC;
1861 
1862 out:
1863 	m_freem(m);
1864 	return error;
1865 }
1866 
1867 SYSINIT(bootp_rootconf, SI_SUB_ROOT_CONF, SI_ORDER_FIRST, bootpc_init, NULL);
1868