xref: /freebsd/sys/nfs/bootp_subr.c (revision 685dc743dc3b5645e34836464128e1c0558b404b)
1 /*-
2  * SPDX-License-Identifier: BSD-4-Clause
3  *
4  * Copyright (c) 1995 Gordon Ross, Adam Glass
5  * Copyright (c) 1992 Regents of the University of California.
6  * All rights reserved.
7  *
8  * This software was developed by the Computer Systems Engineering group
9  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
10  * contributed to Berkeley.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. All advertising materials mentioning features or use of this software
21  *    must display the following acknowledgement:
22  *	This product includes software developed by the University of
23  *	California, Lawrence Berkeley Laboratory and its contributors.
24  * 4. Neither the name of the University nor the names of its contributors
25  *    may be used to endorse or promote products derived from this software
26  *    without specific prior written permission.
27  *
28  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
29  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
32  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38  * SUCH DAMAGE.
39  *
40  * based on:
41  *      nfs/krpc_subr.c
42  *	$NetBSD: krpc_subr.c,v 1.10 1995/08/08 20:43:43 gwr Exp $
43  */
44 
45 #define IN_HISTORICAL_NETS		/* include class masks */
46 
47 #include <sys/cdefs.h>
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/endian.h>
55 #include <sys/jail.h>
56 #include <sys/kernel.h>
57 #include <sys/sockio.h>
58 #include <sys/malloc.h>
59 #include <sys/mount.h>
60 #include <sys/mbuf.h>
61 #include <sys/proc.h>
62 #include <sys/reboot.h>
63 #include <sys/socket.h>
64 #include <sys/socketvar.h>
65 #include <sys/sysctl.h>
66 #include <sys/uio.h>
67 
68 #include <net/if.h>
69 #include <net/if_var.h>
70 #include <net/route.h>
71 #include <net/route/route_ctl.h>
72 
73 #include <netinet/in.h>
74 #include <netinet/in_var.h>
75 #include <net/if_types.h>
76 #include <net/if_dl.h>
77 #include <net/vnet.h>
78 
79 #include <nfs/nfsproto.h>
80 #include <nfsclient/nfs.h>
81 #include <nfs/nfsdiskless.h>
82 #include <nfs/krpc.h>
83 #include <nfs/xdr_subs.h>
84 
85 #define BOOTP_MIN_LEN		300	/* Minimum size of bootp udp packet */
86 
87 #ifndef BOOTP_SETTLE_DELAY
88 #define BOOTP_SETTLE_DELAY 3
89 #endif
90 
91 /*
92  * Wait 10 seconds for interface appearance
93  * USB ethernet adapters might require some time to pop up
94  */
95 #ifndef	BOOTP_IFACE_WAIT_TIMEOUT
96 #define	BOOTP_IFACE_WAIT_TIMEOUT	10
97 #endif
98 
99 /*
100  * What is the longest we will wait before re-sending a request?
101  * Note this is also the frequency of "RPC timeout" messages.
102  * The re-send loop count sup linearly to this maximum, so the
103  * first complaint will happen after (1+2+3+4+5)=15 seconds.
104  */
105 #define	MAX_RESEND_DELAY 5	/* seconds */
106 
107 /* Definitions from RFC951 */
108 struct bootp_packet {
109 	u_int8_t op;
110 	u_int8_t htype;
111 	u_int8_t hlen;
112 	u_int8_t hops;
113 	u_int32_t xid;
114 	u_int16_t secs;
115 	u_int16_t flags;
116 	struct in_addr ciaddr;
117 	struct in_addr yiaddr;
118 	struct in_addr siaddr;
119 	struct in_addr giaddr;
120 	unsigned char chaddr[16];
121 	char sname[64];
122 	char file[128];
123 	unsigned char vend[1222];
124 };
125 
126 struct bootpc_ifcontext {
127 	STAILQ_ENTRY(bootpc_ifcontext) next;
128 	struct bootp_packet call;
129 	struct bootp_packet reply;
130 	int replylen;
131 	int overload;
132 	union {
133 		struct ifreq _ifreq;
134 		struct in_aliasreq _in_alias_req;
135 	} _req;
136 #define	ireq	_req._ifreq
137 #define	iareq	_req._in_alias_req
138 	if_t ifp;
139 	struct sockaddr_dl *sdl;
140 	struct sockaddr_in myaddr;
141 	struct sockaddr_in netmask;
142 	struct sockaddr_in gw;
143 	int gotgw;
144 	int gotnetmask;
145 	int gotrootpath;
146 	int outstanding;
147 	int sentmsg;
148 	u_int32_t xid;
149 	enum {
150 		IF_BOOTP_UNRESOLVED,
151 		IF_BOOTP_RESOLVED,
152 		IF_BOOTP_FAILED,
153 		IF_DHCP_UNRESOLVED,
154 		IF_DHCP_OFFERED,
155 		IF_DHCP_RESOLVED,
156 		IF_DHCP_FAILED,
157 	} state;
158 	int dhcpquerytype;		/* dhcp type sent */
159 	struct in_addr dhcpserver;
160 	int gotdhcpserver;
161 	uint16_t mtu;
162 };
163 
164 #define TAG_MAXLEN 1024
165 struct bootpc_tagcontext {
166 	char buf[TAG_MAXLEN + 1];
167 	int overload;
168 	int badopt;
169 	int badtag;
170 	int foundopt;
171 	int taglen;
172 };
173 
174 struct bootpc_globalcontext {
175 	STAILQ_HEAD(, bootpc_ifcontext) interfaces;
176 	u_int32_t xid;
177 	int any_root_overrides;
178 	int gotrootpath;
179 	int gotgw;
180 	int ifnum;
181 	int secs;
182 	int starttime;
183 	struct bootp_packet reply;
184 	int replylen;
185 	struct bootpc_ifcontext *setrootfs;
186 	struct bootpc_ifcontext *sethostname;
187 	struct bootpc_tagcontext tmptag;
188 	struct bootpc_tagcontext tag;
189 };
190 
191 #define IPPORT_BOOTPC 68
192 #define IPPORT_BOOTPS 67
193 
194 #define BOOTP_REQUEST 1
195 #define BOOTP_REPLY 2
196 
197 /* Common tags */
198 #define TAG_PAD		  0  /* Pad option, implicit length 1 */
199 #define TAG_SUBNETMASK	  1  /* RFC 950 subnet mask */
200 #define TAG_ROUTERS	  3  /* Routers (in order of preference) */
201 #define TAG_HOSTNAME	 12  /* Client host name */
202 #define TAG_ROOT	 17  /* Root path */
203 #define TAG_INTF_MTU	 26  /* Interface MTU Size (RFC2132) */
204 
205 /* DHCP specific tags */
206 #define TAG_OVERLOAD	 52  /* Option Overload */
207 #define TAG_MAXMSGSIZE   57  /* Maximum DHCP Message Size */
208 
209 #define TAG_END		255  /* End Option (i.e. no more options) */
210 
211 /* Overload values */
212 #define OVERLOAD_FILE     1
213 #define OVERLOAD_SNAME    2
214 
215 /* Site specific tags: */
216 #define TAG_ROOTOPTS	130
217 #define TAG_COOKIE	134	/* ascii info for userland, via sysctl */
218 
219 #define TAG_DHCP_MSGTYPE 53
220 #define TAG_DHCP_REQ_ADDR 50
221 #define TAG_DHCP_SERVERID 54
222 #define TAG_DHCP_LEASETIME 51
223 
224 #define TAG_VENDOR_INDENTIFIER 60
225 
226 #define DHCP_NOMSG    0
227 #define DHCP_DISCOVER 1
228 #define DHCP_OFFER    2
229 #define DHCP_REQUEST  3
230 #define DHCP_ACK      5
231 
232 /* NFS read/write block size */
233 #ifndef BOOTP_BLOCKSIZE
234 #define	BOOTP_BLOCKSIZE	8192
235 #endif
236 
237 static char bootp_cookie[128];
238 static struct socket *bootp_so;
239 SYSCTL_STRING(_kern, OID_AUTO, bootp_cookie, CTLFLAG_RD,
240 	bootp_cookie, 0, "Cookie (T134) supplied by bootp server");
241 
242 /* mountd RPC */
243 static int	md_mount(struct sockaddr_in *mdsin, char *path, u_char *fhp,
244 		    int *fhsizep, struct nfs_args *args, struct thread *td);
245 static int	setfs(struct sockaddr_in *addr, char *path, char *p,
246 		    const struct in_addr *siaddr);
247 static int	getdec(char **ptr);
248 static int	getip(char **ptr, struct in_addr *ip);
249 static void	mountopts(struct nfs_args *args, char *p);
250 static int	xdr_opaque_decode(struct mbuf **ptr, u_char *buf, int len);
251 static int	xdr_int_decode(struct mbuf **ptr, int *iptr);
252 static void	print_in_addr(struct in_addr addr);
253 static void	print_sin_addr(struct sockaddr_in *addr);
254 static void	clear_sinaddr(struct sockaddr_in *sin);
255 static void	allocifctx(struct bootpc_globalcontext *gctx);
256 static void	bootpc_compose_query(struct bootpc_ifcontext *ifctx,
257 		    struct thread *td);
258 static unsigned char *bootpc_tag(struct bootpc_tagcontext *tctx,
259 		    struct bootp_packet *bp, int len, int tag);
260 static void bootpc_tag_helper(struct bootpc_tagcontext *tctx,
261 		    unsigned char *start, int len, int tag);
262 
263 #ifdef BOOTP_DEBUG
264 void bootpboot_p_iflist(void);
265 #endif
266 
267 static int	bootpc_call(struct bootpc_globalcontext *gctx,
268 		    struct thread *td);
269 
270 static void	bootpc_fakeup_interface(struct bootpc_ifcontext *ifctx,
271 		    struct thread *td);
272 
273 static void	bootpc_adjust_interface(struct bootpc_ifcontext *ifctx,
274 		    struct bootpc_globalcontext *gctx, struct thread *td);
275 
276 static void	bootpc_decode_reply(struct nfsv3_diskless *nd,
277 		    struct bootpc_ifcontext *ifctx,
278 		    struct bootpc_globalcontext *gctx);
279 
280 static int	bootpc_received(struct bootpc_globalcontext *gctx,
281 		    struct bootpc_ifcontext *ifctx);
282 
283 static __inline int bootpc_ifctx_isresolved(struct bootpc_ifcontext *ifctx);
284 static __inline int bootpc_ifctx_isunresolved(struct bootpc_ifcontext *ifctx);
285 static __inline int bootpc_ifctx_isfailed(struct bootpc_ifcontext *ifctx);
286 
287 /*
288  * In order to have multiple active interfaces with address 0.0.0.0
289  * and be able to send data to a selected interface, we first set
290  * mask to /8 on all interfaces, and temporarily set it to /0 when
291  * doing sosend().
292  */
293 
294 #ifdef BOOTP_DEBUG
295 static u_int
bootpboot_p_ifa(void * ifp,struct ifaddr * ifa,u_int count __unused)296 bootpboot_p_ifa(void *ifp, struct ifaddr *ifa, u_int count __unused)
297 {
298 
299 	printf("%s flags %x, addr ",
300 	       if_name(ifp), if_getflags(ifp));
301 	print_sin_addr((struct sockaddr_in *) ifa->ifa_addr);
302 	printf(", broadcast ");
303 	print_sin_addr((struct sockaddr_in *) ifa->ifa_dstaddr);
304 	printf(", netmask ");
305 	print_sin_addr((struct sockaddr_in *) ifa->ifa_netmask);
306 	printf("\n");
307 
308 	return (0);
309 }
310 
311 void
bootpboot_p_iflist(void)312 bootpboot_p_iflist(void)
313 {
314 	struct epoch_tracker et;
315 	struct if_iter iter;
316 	if_t ifp;
317 
318 	printf("Interface list:\n");
319 	NET_EPOCH_ENTER(et);
320 	for (ifp = if_iter_start(&iter); ifp != NULL; ifp = if_iter_next(&iter))
321 		if_foreach_addr_type(ifp, AF_INET, bootpboot_p_ifa, ifp);
322 	if_iter_finish(&iter);
323 	NET_EPOCH_EXIT(et);
324 }
325 #endif /* defined(BOOTP_DEBUG) */
326 
327 static void
clear_sinaddr(struct sockaddr_in * sin)328 clear_sinaddr(struct sockaddr_in *sin)
329 {
330 
331 	bzero(sin, sizeof(*sin));
332 	sin->sin_len = sizeof(*sin);
333 	sin->sin_family = AF_INET;
334 	sin->sin_addr.s_addr = INADDR_ANY; /* XXX: htonl(INAADDR_ANY) ? */
335 	sin->sin_port = 0;
336 }
337 
338 static void
allocifctx(struct bootpc_globalcontext * gctx)339 allocifctx(struct bootpc_globalcontext *gctx)
340 {
341 	struct bootpc_ifcontext *ifctx;
342 
343 	ifctx = malloc(sizeof(*ifctx), M_TEMP, M_WAITOK | M_ZERO);
344 	ifctx->xid = gctx->xid;
345 #ifdef BOOTP_NO_DHCP
346 	ifctx->state = IF_BOOTP_UNRESOLVED;
347 #else
348 	ifctx->state = IF_DHCP_UNRESOLVED;
349 #endif
350 	gctx->xid += 0x100;
351 	STAILQ_INSERT_TAIL(&gctx->interfaces, ifctx, next);
352 }
353 
354 static __inline int
bootpc_ifctx_isresolved(struct bootpc_ifcontext * ifctx)355 bootpc_ifctx_isresolved(struct bootpc_ifcontext *ifctx)
356 {
357 
358 	if (ifctx->state == IF_BOOTP_RESOLVED ||
359 	    ifctx->state == IF_DHCP_RESOLVED)
360 		return 1;
361 	return 0;
362 }
363 
364 static __inline int
bootpc_ifctx_isunresolved(struct bootpc_ifcontext * ifctx)365 bootpc_ifctx_isunresolved(struct bootpc_ifcontext *ifctx)
366 {
367 
368 	if (ifctx->state == IF_BOOTP_UNRESOLVED ||
369 	    ifctx->state == IF_DHCP_UNRESOLVED)
370 		return 1;
371 	return 0;
372 }
373 
374 static __inline int
bootpc_ifctx_isfailed(struct bootpc_ifcontext * ifctx)375 bootpc_ifctx_isfailed(struct bootpc_ifcontext *ifctx)
376 {
377 
378 	if (ifctx->state == IF_BOOTP_FAILED ||
379 	    ifctx->state == IF_DHCP_FAILED)
380 		return 1;
381 	return 0;
382 }
383 
384 static int
bootpc_received(struct bootpc_globalcontext * gctx,struct bootpc_ifcontext * ifctx)385 bootpc_received(struct bootpc_globalcontext *gctx,
386     struct bootpc_ifcontext *ifctx)
387 {
388 	unsigned char dhcpreplytype;
389 	char *p;
390 
391 	/*
392 	 * Need timeout for fallback to less
393 	 * desirable alternative.
394 	 */
395 
396 	/* This call used for the side effect (badopt flag) */
397 	(void) bootpc_tag(&gctx->tmptag, &gctx->reply,
398 			  gctx->replylen,
399 			  TAG_END);
400 
401 	/* If packet is invalid, ignore it */
402 	if (gctx->tmptag.badopt != 0)
403 		return 0;
404 
405 	p = bootpc_tag(&gctx->tmptag, &gctx->reply,
406 		       gctx->replylen, TAG_DHCP_MSGTYPE);
407 	if (p != NULL)
408 		dhcpreplytype = *p;
409 	else
410 		dhcpreplytype = DHCP_NOMSG;
411 
412 	switch (ifctx->dhcpquerytype) {
413 	case DHCP_DISCOVER:
414 		if (dhcpreplytype != DHCP_OFFER 	/* Normal DHCP offer */
415 #ifndef BOOTP_FORCE_DHCP
416 		    && dhcpreplytype != DHCP_NOMSG	/* Fallback to BOOTP */
417 #endif
418 			)
419 			return 0;
420 		break;
421 	case DHCP_REQUEST:
422 		if (dhcpreplytype != DHCP_ACK)
423 			return 0;
424 	case DHCP_NOMSG:
425 		break;
426 	}
427 
428 	/* Ignore packet unless it gives us a root tag we didn't have */
429 
430 	if ((ifctx->state == IF_BOOTP_RESOLVED ||
431 	     (ifctx->dhcpquerytype == DHCP_DISCOVER &&
432 	      (ifctx->state == IF_DHCP_OFFERED ||
433 	       ifctx->state == IF_DHCP_RESOLVED))) &&
434 	    (bootpc_tag(&gctx->tmptag, &ifctx->reply,
435 			ifctx->replylen,
436 			TAG_ROOT) != NULL ||
437 	     bootpc_tag(&gctx->tmptag, &gctx->reply,
438 			gctx->replylen,
439 			TAG_ROOT) == NULL))
440 		return 0;
441 
442 	bcopy(&gctx->reply, &ifctx->reply, gctx->replylen);
443 	ifctx->replylen = gctx->replylen;
444 
445 	/* XXX: Only reset if 'perfect' response */
446 	if (ifctx->state == IF_BOOTP_UNRESOLVED)
447 		ifctx->state = IF_BOOTP_RESOLVED;
448 	else if (ifctx->state == IF_DHCP_UNRESOLVED &&
449 		 ifctx->dhcpquerytype == DHCP_DISCOVER) {
450 		if (dhcpreplytype == DHCP_OFFER)
451 			ifctx->state = IF_DHCP_OFFERED;
452 		else
453 			ifctx->state = IF_BOOTP_RESOLVED;	/* Fallback */
454 	} else if (ifctx->state == IF_DHCP_OFFERED &&
455 		   ifctx->dhcpquerytype == DHCP_REQUEST)
456 		ifctx->state = IF_DHCP_RESOLVED;
457 
458 	if (ifctx->dhcpquerytype == DHCP_DISCOVER &&
459 	    ifctx->state != IF_BOOTP_RESOLVED) {
460 		p = bootpc_tag(&gctx->tmptag, &ifctx->reply,
461 			       ifctx->replylen, TAG_DHCP_SERVERID);
462 		if (p != NULL && gctx->tmptag.taglen == 4) {
463 			memcpy(&ifctx->dhcpserver, p, 4);
464 			ifctx->gotdhcpserver = 1;
465 		} else
466 			ifctx->gotdhcpserver = 0;
467 		return 1;
468 	}
469 
470 	ifctx->gotrootpath = (bootpc_tag(&gctx->tmptag, &ifctx->reply,
471 					 ifctx->replylen,
472 					 TAG_ROOT) != NULL);
473 	ifctx->gotgw = (bootpc_tag(&gctx->tmptag, &ifctx->reply,
474 				   ifctx->replylen,
475 				   TAG_ROUTERS) != NULL);
476 	ifctx->gotnetmask = (bootpc_tag(&gctx->tmptag, &ifctx->reply,
477 					ifctx->replylen,
478 					TAG_SUBNETMASK) != NULL);
479 	return 1;
480 }
481 
482 static int
bootpc_call(struct bootpc_globalcontext * gctx,struct thread * td)483 bootpc_call(struct bootpc_globalcontext *gctx, struct thread *td)
484 {
485 	struct sockaddr_in *sin, dst;
486 	struct uio auio;
487 	struct sockopt sopt;
488 	struct iovec aio;
489 	int error, on, rcvflg, timo, len;
490 	time_t atimo;
491 	time_t rtimo;
492 	struct timeval tv;
493 	struct bootpc_ifcontext *ifctx;
494 	int outstanding;
495 	int gotrootpath;
496 	int retry;
497 	const char *s;
498 
499 	tv.tv_sec = 1;
500 	tv.tv_usec = 0;
501 	bzero(&sopt, sizeof(sopt));
502 	sopt.sopt_dir = SOPT_SET;
503 	sopt.sopt_level = SOL_SOCKET;
504 	sopt.sopt_name = SO_RCVTIMEO;
505 	sopt.sopt_val = &tv;
506 	sopt.sopt_valsize = sizeof tv;
507 
508 	error = sosetopt(bootp_so, &sopt);
509 	if (error != 0)
510 		goto out;
511 
512 	/*
513 	 * Enable broadcast.
514 	 */
515 	on = 1;
516 	sopt.sopt_name = SO_BROADCAST;
517 	sopt.sopt_val = &on;
518 	sopt.sopt_valsize = sizeof on;
519 
520 	error = sosetopt(bootp_so, &sopt);
521 	if (error != 0)
522 		goto out;
523 
524 	/*
525 	 * Disable routing.
526 	 */
527 
528 	on = 1;
529 	sopt.sopt_name = SO_DONTROUTE;
530 	sopt.sopt_val = &on;
531 	sopt.sopt_valsize = sizeof on;
532 
533 	error = sosetopt(bootp_so, &sopt);
534 	if (error != 0)
535 		goto out;
536 
537 	/*
538 	 * Bind the local endpoint to a bootp client port.
539 	 */
540 	sin = &dst;
541 	clear_sinaddr(sin);
542 	sin->sin_port = htons(IPPORT_BOOTPC);
543 	error = sobind(bootp_so, (struct sockaddr *)sin, td);
544 	if (error != 0) {
545 		printf("bind failed\n");
546 		goto out;
547 	}
548 
549 	/*
550 	 * Setup socket address for the server.
551 	 */
552 	sin = &dst;
553 	clear_sinaddr(sin);
554 	sin->sin_addr.s_addr = INADDR_BROADCAST;
555 	sin->sin_port = htons(IPPORT_BOOTPS);
556 
557 	/*
558 	 * Send it, repeatedly, until a reply is received,
559 	 * but delay each re-send by an increasing amount.
560 	 * If the delay hits the maximum, start complaining.
561 	 */
562 	timo = 0;
563 	rtimo = 0;
564 	for (;;) {
565 		outstanding = 0;
566 		gotrootpath = 0;
567 
568 		STAILQ_FOREACH(ifctx, &gctx->interfaces, next) {
569 			if (bootpc_ifctx_isresolved(ifctx) != 0 &&
570 			    bootpc_tag(&gctx->tmptag, &ifctx->reply,
571 				       ifctx->replylen,
572 				       TAG_ROOT) != NULL)
573 				gotrootpath = 1;
574 		}
575 
576 		STAILQ_FOREACH(ifctx, &gctx->interfaces, next) {
577 			struct in_aliasreq *ifra = &ifctx->iareq;
578 			sin = (struct sockaddr_in *)&ifra->ifra_mask;
579 
580 			ifctx->outstanding = 0;
581 			if (bootpc_ifctx_isresolved(ifctx)  != 0 &&
582 			    gotrootpath != 0) {
583 				continue;
584 			}
585 			if (bootpc_ifctx_isfailed(ifctx) != 0)
586 				continue;
587 
588 			outstanding++;
589 			ifctx->outstanding = 1;
590 
591 			/* Proceed to next step in DHCP negotiation */
592 			if ((ifctx->state == IF_DHCP_OFFERED &&
593 			     ifctx->dhcpquerytype != DHCP_REQUEST) ||
594 			    (ifctx->state == IF_DHCP_UNRESOLVED &&
595 			     ifctx->dhcpquerytype != DHCP_DISCOVER) ||
596 			    (ifctx->state == IF_BOOTP_UNRESOLVED &&
597 			     ifctx->dhcpquerytype != DHCP_NOMSG)) {
598 				ifctx->sentmsg = 0;
599 				bootpc_compose_query(ifctx, td);
600 			}
601 
602 			/* Send BOOTP request (or re-send). */
603 
604 			if (ifctx->sentmsg == 0) {
605 				switch(ifctx->dhcpquerytype) {
606 				case DHCP_DISCOVER:
607 					s = "DHCP Discover";
608 					break;
609 				case DHCP_REQUEST:
610 					s = "DHCP Request";
611 					break;
612 				case DHCP_NOMSG:
613 				default:
614 					s = "BOOTP Query";
615 					break;
616 				}
617 				printf("Sending %s packet from "
618 				       "interface %s (%*D)\n",
619 				       s,
620 				       ifctx->ireq.ifr_name,
621 				       ifctx->sdl->sdl_alen,
622 				       (unsigned char *) LLADDR(ifctx->sdl),
623 				       ":");
624 				ifctx->sentmsg = 1;
625 			}
626 
627 			aio.iov_base = (caddr_t) &ifctx->call;
628 			aio.iov_len = sizeof(ifctx->call);
629 
630 			auio.uio_iov = &aio;
631 			auio.uio_iovcnt = 1;
632 			auio.uio_segflg = UIO_SYSSPACE;
633 			auio.uio_rw = UIO_WRITE;
634 			auio.uio_offset = 0;
635 			auio.uio_resid = sizeof(ifctx->call);
636 			auio.uio_td = td;
637 
638 			/* Set netmask to 0.0.0.0 */
639 			clear_sinaddr(sin);
640 			error = ifioctl(bootp_so, SIOCAIFADDR, (caddr_t)ifra,
641 			    td);
642 			if (error != 0)
643 				panic("%s: SIOCAIFADDR, error=%d", __func__,
644 				    error);
645 
646 			error = sosend(bootp_so, (struct sockaddr *) &dst,
647 				       &auio, NULL, NULL, 0, td);
648 			if (error != 0)
649 				printf("%s: sosend: %d state %08x\n", __func__,
650 				    error, (int )bootp_so->so_state);
651 
652 			/* Set netmask to 255.0.0.0 */
653 			sin->sin_addr.s_addr = htonl(0xff000000);
654 			error = ifioctl(bootp_so, SIOCAIFADDR, (caddr_t)ifra,
655 			    td);
656 			if (error != 0)
657 				panic("%s: SIOCAIFADDR, error=%d", __func__,
658 				    error);
659 		}
660 
661 		if (outstanding == 0 &&
662 		    (rtimo == 0 || time_second >= rtimo)) {
663 			error = 0;
664 			goto out;
665 		}
666 
667 		/* Determine new timeout. */
668 		if (timo < MAX_RESEND_DELAY)
669 			timo++;
670 		else {
671 			printf("DHCP/BOOTP timeout for server ");
672 			print_sin_addr(&dst);
673 			printf("\n");
674 		}
675 
676 		/*
677 		 * Wait for up to timo seconds for a reply.
678 		 * The socket receive timeout was set to 1 second.
679 		 */
680 		atimo = timo + time_second;
681 		while (time_second < atimo) {
682 			aio.iov_base = (caddr_t) &gctx->reply;
683 			aio.iov_len = sizeof(gctx->reply);
684 
685 			auio.uio_iov = &aio;
686 			auio.uio_iovcnt = 1;
687 			auio.uio_segflg = UIO_SYSSPACE;
688 			auio.uio_rw = UIO_READ;
689 			auio.uio_offset = 0;
690 			auio.uio_resid = sizeof(gctx->reply);
691 			auio.uio_td = td;
692 
693 			rcvflg = 0;
694 			error = soreceive(bootp_so, NULL, &auio,
695 					  NULL, NULL, &rcvflg);
696 			gctx->secs = time_second - gctx->starttime;
697 			STAILQ_FOREACH(ifctx, &gctx->interfaces, next) {
698 				if (bootpc_ifctx_isresolved(ifctx) != 0 ||
699 				    bootpc_ifctx_isfailed(ifctx) != 0)
700 					continue;
701 
702 				ifctx->call.secs = htons(gctx->secs);
703 			}
704 			if (error == EWOULDBLOCK)
705 				continue;
706 			if (error != 0)
707 				goto out;
708 			len = sizeof(gctx->reply) - auio.uio_resid;
709 
710 			/* Do we have the required number of bytes ? */
711 			if (len < BOOTP_MIN_LEN)
712 				continue;
713 			gctx->replylen = len;
714 
715 			/* Is it a reply? */
716 			if (gctx->reply.op != BOOTP_REPLY)
717 				continue;
718 
719 			/* Is this an answer to our query */
720 			STAILQ_FOREACH(ifctx, &gctx->interfaces, next) {
721 				if (gctx->reply.xid != ifctx->call.xid)
722 					continue;
723 
724 				/* Same HW address size ? */
725 				if (gctx->reply.hlen != ifctx->call.hlen)
726 					continue;
727 
728 				/* Correct HW address ? */
729 				if (bcmp(gctx->reply.chaddr,
730 					 ifctx->call.chaddr,
731 					 ifctx->call.hlen) != 0)
732 					continue;
733 
734 				break;
735 			}
736 
737 			if (ifctx != NULL) {
738 				s =  bootpc_tag(&gctx->tmptag,
739 						&gctx->reply,
740 						gctx->replylen,
741 						TAG_DHCP_MSGTYPE);
742 				if (s != NULL) {
743 					switch (*s) {
744 					case DHCP_OFFER:
745 						s = "DHCP Offer";
746 						break;
747 					case DHCP_ACK:
748 						s = "DHCP Ack";
749 						break;
750 					default:
751 						s = "DHCP (unexpected)";
752 						break;
753 					}
754 				} else
755 					s = "BOOTP Reply";
756 
757 				printf("Received %s packet"
758 				       " on %s from ",
759 				       s,
760 				       ifctx->ireq.ifr_name);
761 				print_in_addr(gctx->reply.siaddr);
762 				if (gctx->reply.giaddr.s_addr !=
763 				    htonl(INADDR_ANY)) {
764 					printf(" via ");
765 					print_in_addr(gctx->reply.giaddr);
766 				}
767 				if (bootpc_received(gctx, ifctx) != 0) {
768 					printf(" (accepted)");
769 					if (ifctx->outstanding) {
770 						ifctx->outstanding = 0;
771 						outstanding--;
772 					}
773 					/* Network settle delay */
774 					if (outstanding == 0)
775 						atimo = time_second +
776 							BOOTP_SETTLE_DELAY;
777 				} else
778 					printf(" (ignored)");
779 				if (ifctx->gotrootpath ||
780 				    gctx->any_root_overrides) {
781 					gotrootpath = 1;
782 					rtimo = time_second +
783 						BOOTP_SETTLE_DELAY;
784 					if (ifctx->gotrootpath)
785 						printf(" (got root path)");
786 				}
787 				printf("\n");
788 			}
789 		} /* while secs */
790 #ifdef BOOTP_TIMEOUT
791 		if (gctx->secs > BOOTP_TIMEOUT && BOOTP_TIMEOUT > 0)
792 			break;
793 #endif
794 		/* Force a retry if halfway in DHCP negotiation */
795 		retry = 0;
796 		STAILQ_FOREACH(ifctx, &gctx->interfaces, next)
797 			if (ifctx->state == IF_DHCP_OFFERED) {
798 				if (ifctx->dhcpquerytype == DHCP_DISCOVER)
799 					retry = 1;
800 				else
801 					ifctx->state = IF_DHCP_UNRESOLVED;
802 			}
803 
804 		if (retry != 0)
805 			continue;
806 
807 		if (gotrootpath != 0) {
808 			gctx->gotrootpath = gotrootpath;
809 			if (rtimo != 0 && time_second >= rtimo)
810 				break;
811 		}
812 	} /* forever send/receive */
813 
814 	/*
815 	 * XXX: These are errors of varying seriousness being silently
816 	 * ignored
817 	 */
818 
819 	STAILQ_FOREACH(ifctx, &gctx->interfaces, next)
820 		if (bootpc_ifctx_isresolved(ifctx) == 0) {
821 			printf("%s timeout for interface %s\n",
822 			       ifctx->dhcpquerytype != DHCP_NOMSG ?
823 			       "DHCP" : "BOOTP",
824 			       ifctx->ireq.ifr_name);
825 		}
826 
827 	if (gctx->gotrootpath != 0) {
828 #if 0
829 		printf("Got a root path, ignoring remaining timeout\n");
830 #endif
831 		error = 0;
832 		goto out;
833 	}
834 #ifndef BOOTP_NFSROOT
835 	STAILQ_FOREACH(ifctx, &gctx->interfaces, next)
836 		if (bootpc_ifctx_isresolved(ifctx) != 0) {
837 			error = 0;
838 			goto out;
839 		}
840 #endif
841 	error = ETIMEDOUT;
842 
843 out:
844 	return (error);
845 }
846 
847 static void
bootpc_fakeup_interface(struct bootpc_ifcontext * ifctx,struct thread * td)848 bootpc_fakeup_interface(struct bootpc_ifcontext *ifctx, struct thread *td)
849 {
850 	struct ifreq *ifr;
851 	struct in_aliasreq *ifra;
852 	struct sockaddr_in *sin;
853 	int error;
854 
855 	ifr = &ifctx->ireq;
856 	ifra = &ifctx->iareq;
857 
858 	/*
859 	 * Bring up the interface.
860 	 *
861 	 * Get the old interface flags and or IFF_UP into them; if
862 	 * IFF_UP set blindly, interface selection can be clobbered.
863 	 */
864 	error = ifioctl(bootp_so, SIOCGIFFLAGS, (caddr_t)ifr, td);
865 	if (error != 0)
866 		panic("%s: SIOCGIFFLAGS, error=%d", __func__, error);
867 	ifr->ifr_flags |= IFF_UP;
868 	error = ifioctl(bootp_so, SIOCSIFFLAGS, (caddr_t)ifr, td);
869 	if (error != 0)
870 		panic("%s: SIOCSIFFLAGS, error=%d", __func__, error);
871 
872 	/*
873 	 * Do enough of ifconfig(8) so that the chosen interface
874 	 * can talk to the servers. Set address to 0.0.0.0/8 and
875 	 * broadcast address to local broadcast.
876 	 */
877 	sin = (struct sockaddr_in *)&ifra->ifra_addr;
878 	clear_sinaddr(sin);
879 	sin = (struct sockaddr_in *)&ifra->ifra_mask;
880 	clear_sinaddr(sin);
881 	sin->sin_addr.s_addr = htonl(0xff000000);
882 	sin = (struct sockaddr_in *)&ifra->ifra_broadaddr;
883 	clear_sinaddr(sin);
884 	sin->sin_addr.s_addr = htonl(INADDR_BROADCAST);
885 	error = ifioctl(bootp_so, SIOCAIFADDR, (caddr_t)ifra, td);
886 	if (error != 0)
887 		panic("%s: SIOCAIFADDR, error=%d", __func__, error);
888 }
889 
890 static void
bootpc_shutdown_interface(struct bootpc_ifcontext * ifctx,struct thread * td)891 bootpc_shutdown_interface(struct bootpc_ifcontext *ifctx, struct thread *td)
892 {
893 	struct ifreq *ifr;
894 	struct sockaddr_in *sin;
895 	int error;
896 
897 	ifr = &ifctx->ireq;
898 
899 	printf("Shutdown interface %s\n", ifctx->ireq.ifr_name);
900 	error = ifioctl(bootp_so, SIOCGIFFLAGS, (caddr_t)ifr, td);
901 	if (error != 0)
902 		panic("%s: SIOCGIFFLAGS, error=%d", __func__, error);
903 	ifr->ifr_flags &= ~IFF_UP;
904 	error = ifioctl(bootp_so, SIOCSIFFLAGS, (caddr_t)ifr, td);
905 	if (error != 0)
906 		panic("%s: SIOCSIFFLAGS, error=%d", __func__, error);
907 
908 	sin = (struct sockaddr_in *) &ifr->ifr_addr;
909 	clear_sinaddr(sin);
910 	error = ifioctl(bootp_so, SIOCDIFADDR, (caddr_t) ifr, td);
911 	if (error != 0)
912 		panic("%s: SIOCDIFADDR, error=%d", __func__, error);
913 }
914 
915 static void
bootpc_adjust_interface(struct bootpc_ifcontext * ifctx,struct bootpc_globalcontext * gctx,struct thread * td)916 bootpc_adjust_interface(struct bootpc_ifcontext *ifctx,
917     struct bootpc_globalcontext *gctx, struct thread *td)
918 {
919 	int error;
920 	struct sockaddr_in *sin;
921 	struct ifreq *ifr;
922 	struct in_aliasreq *ifra;
923 	struct sockaddr_in *myaddr;
924 	struct sockaddr_in *netmask;
925 
926 	ifr = &ifctx->ireq;
927 	ifra = &ifctx->iareq;
928 	myaddr = &ifctx->myaddr;
929 	netmask = &ifctx->netmask;
930 
931 	if (bootpc_ifctx_isresolved(ifctx) == 0) {
932 		/* Shutdown interfaces where BOOTP failed */
933 		bootpc_shutdown_interface(ifctx, td);
934 		return;
935 	}
936 
937 	printf("Adjusted interface %s", ifctx->ireq.ifr_name);
938 
939 	/* Do BOOTP interface options */
940 	if (ifctx->mtu != 0) {
941 		printf(" (MTU=%d%s)", ifctx->mtu,
942 		    (ifctx->mtu > 1514) ? "/JUMBO" : "");
943 		ifr->ifr_mtu = ifctx->mtu;
944 		error = ifioctl(bootp_so, SIOCSIFMTU, (caddr_t) ifr, td);
945 		if (error != 0)
946 			panic("%s: SIOCSIFMTU, error=%d", __func__, error);
947 	}
948 	printf("\n");
949 
950 	/*
951 	 * Do enough of ifconfig(8) so that the chosen interface
952 	 * can talk to the servers.  (just set the address)
953 	 */
954 	sin = (struct sockaddr_in *) &ifr->ifr_addr;
955 	clear_sinaddr(sin);
956 	error = ifioctl(bootp_so, SIOCDIFADDR, (caddr_t) ifr, td);
957 	if (error != 0)
958 		panic("%s: SIOCDIFADDR, error=%d", __func__, error);
959 
960 	bcopy(myaddr, &ifra->ifra_addr, sizeof(*myaddr));
961 	bcopy(netmask, &ifra->ifra_mask, sizeof(*netmask));
962 	clear_sinaddr(&ifra->ifra_broadaddr);
963 	ifra->ifra_broadaddr.sin_addr.s_addr = myaddr->sin_addr.s_addr |
964 	    ~netmask->sin_addr.s_addr;
965 
966 	error = ifioctl(bootp_so, SIOCAIFADDR, (caddr_t)ifra, td);
967 	if (error != 0)
968 		panic("%s: SIOCAIFADDR, error=%d", __func__, error);
969 }
970 
971 static void
bootpc_add_default_route(struct bootpc_ifcontext * ifctx)972 bootpc_add_default_route(struct bootpc_ifcontext *ifctx)
973 {
974 	int error;
975 	struct sockaddr_in defdst;
976 	struct sockaddr_in defmask;
977 	struct rt_addrinfo info;
978 	struct rib_cmd_info rc;
979 
980 	if (ifctx->gw.sin_addr.s_addr == htonl(INADDR_ANY))
981 		return;
982 
983 	clear_sinaddr(&defdst);
984 	clear_sinaddr(&defmask);
985 
986 	bzero((caddr_t)&info, sizeof(info));
987 	info.rti_flags = RTF_UP | RTF_GATEWAY | RTF_STATIC;
988 	info.rti_info[RTAX_DST] = (struct sockaddr *)&defdst;
989 	info.rti_info[RTAX_NETMASK] = (struct sockaddr *)&defmask;
990 	info.rti_info[RTAX_GATEWAY] = (struct sockaddr *)&ifctx->gw;
991 
992 	error = rib_action(RT_DEFAULT_FIB, RTM_ADD, &info, &rc);
993 
994 	if (error != 0) {
995 		printf("%s: RTM_ADD, error=%d\n", __func__, error);
996 	}
997 }
998 
999 static void
bootpc_remove_default_route(struct bootpc_ifcontext * ifctx)1000 bootpc_remove_default_route(struct bootpc_ifcontext *ifctx)
1001 {
1002 	int error;
1003 	struct sockaddr_in defdst;
1004 	struct sockaddr_in defmask;
1005 	struct rt_addrinfo info;
1006 	struct rib_cmd_info rc;
1007 
1008 	if (ifctx->gw.sin_addr.s_addr == htonl(INADDR_ANY))
1009 		return;
1010 
1011 	clear_sinaddr(&defdst);
1012 	clear_sinaddr(&defmask);
1013 
1014 	bzero((caddr_t)&info, sizeof(info));
1015 	info.rti_flags = RTF_UP | RTF_GATEWAY | RTF_STATIC;
1016 	info.rti_info[RTAX_DST] = (struct sockaddr *)&defdst;
1017 	info.rti_info[RTAX_NETMASK] = (struct sockaddr *)&defmask;
1018 	info.rti_info[RTAX_GATEWAY] = (struct sockaddr *)&ifctx->gw;
1019 
1020 	error = rib_action(RT_DEFAULT_FIB, RTM_DELETE, &info, &rc);
1021 	if (error != 0) {
1022 		printf("%s: RTM_DELETE, error=%d\n", __func__, error);
1023 	}
1024 }
1025 
1026 static int
setfs(struct sockaddr_in * addr,char * path,char * p,const struct in_addr * siaddr)1027 setfs(struct sockaddr_in *addr, char *path, char *p,
1028     const struct in_addr *siaddr)
1029 {
1030 
1031 	if (getip(&p, &addr->sin_addr) == 0) {
1032 		if (siaddr != NULL && *p == '/')
1033 			bcopy(siaddr, &addr->sin_addr, sizeof(struct in_addr));
1034 		else
1035 			return 0;
1036 	} else {
1037 		if (*p != ':')
1038 			return 0;
1039 		p++;
1040 	}
1041 
1042 	addr->sin_len = sizeof(struct sockaddr_in);
1043 	addr->sin_family = AF_INET;
1044 
1045 	strlcpy(path, p, MNAMELEN);
1046 	return 1;
1047 }
1048 
1049 static int
getip(char ** ptr,struct in_addr * addr)1050 getip(char **ptr, struct in_addr *addr)
1051 {
1052 	char *p;
1053 	unsigned int ip;
1054 	int val;
1055 
1056 	p = *ptr;
1057 	ip = 0;
1058 	if (((val = getdec(&p)) < 0) || (val > 255))
1059 		return 0;
1060 	ip = val << 24;
1061 	if (*p != '.')
1062 		return 0;
1063 	p++;
1064 	if (((val = getdec(&p)) < 0) || (val > 255))
1065 		return 0;
1066 	ip |= (val << 16);
1067 	if (*p != '.')
1068 		return 0;
1069 	p++;
1070 	if (((val = getdec(&p)) < 0) || (val > 255))
1071 		return 0;
1072 	ip |= (val << 8);
1073 	if (*p != '.')
1074 		return 0;
1075 	p++;
1076 	if (((val = getdec(&p)) < 0) || (val > 255))
1077 		return 0;
1078 	ip |= val;
1079 
1080 	addr->s_addr = htonl(ip);
1081 	*ptr = p;
1082 	return 1;
1083 }
1084 
1085 static int
getdec(char ** ptr)1086 getdec(char **ptr)
1087 {
1088 	char *p;
1089 	int ret;
1090 
1091 	p = *ptr;
1092 	ret = 0;
1093 	if ((*p < '0') || (*p > '9'))
1094 		return -1;
1095 	while ((*p >= '0') && (*p <= '9')) {
1096 		ret = ret * 10 + (*p - '0');
1097 		p++;
1098 	}
1099 	*ptr = p;
1100 	return ret;
1101 }
1102 
1103 static void
mountopts(struct nfs_args * args,char * p)1104 mountopts(struct nfs_args *args, char *p)
1105 {
1106 	args->version = NFS_ARGSVERSION;
1107 	args->rsize = BOOTP_BLOCKSIZE;
1108 	args->wsize = BOOTP_BLOCKSIZE;
1109 	args->flags = NFSMNT_RSIZE | NFSMNT_WSIZE | NFSMNT_RESVPORT;
1110 	args->sotype = SOCK_DGRAM;
1111 	if (p != NULL)
1112 		nfs_parse_options(p, args);
1113 }
1114 
1115 static int
xdr_opaque_decode(struct mbuf ** mptr,u_char * buf,int len)1116 xdr_opaque_decode(struct mbuf **mptr, u_char *buf, int len)
1117 {
1118 	struct mbuf *m;
1119 	int alignedlen;
1120 
1121 	m = *mptr;
1122 	alignedlen = ( len + 3 ) & ~3;
1123 
1124 	if (m->m_len < alignedlen) {
1125 		m = m_pullup(m, alignedlen);
1126 		if (m == NULL) {
1127 			*mptr = NULL;
1128 			return EBADRPC;
1129 		}
1130 	}
1131 	bcopy(mtod(m, u_char *), buf, len);
1132 	m_adj(m, alignedlen);
1133 	*mptr = m;
1134 	return 0;
1135 }
1136 
1137 static int
xdr_int_decode(struct mbuf ** mptr,int * iptr)1138 xdr_int_decode(struct mbuf **mptr, int *iptr)
1139 {
1140 	u_int32_t i;
1141 
1142 	if (xdr_opaque_decode(mptr, (u_char *) &i, sizeof(u_int32_t)) != 0)
1143 		return EBADRPC;
1144 	*iptr = fxdr_unsigned(u_int32_t, i);
1145 	return 0;
1146 }
1147 
1148 static void
print_sin_addr(struct sockaddr_in * sin)1149 print_sin_addr(struct sockaddr_in *sin)
1150 {
1151 
1152 	print_in_addr(sin->sin_addr);
1153 }
1154 
1155 static void
print_in_addr(struct in_addr addr)1156 print_in_addr(struct in_addr addr)
1157 {
1158 	unsigned int ip;
1159 
1160 	ip = ntohl(addr.s_addr);
1161 	printf("%d.%d.%d.%d",
1162 	       ip >> 24, (ip >> 16) & 255, (ip >> 8) & 255, ip & 255);
1163 }
1164 
1165 static void
bootpc_compose_query(struct bootpc_ifcontext * ifctx,struct thread * td)1166 bootpc_compose_query(struct bootpc_ifcontext *ifctx, struct thread *td)
1167 {
1168 	unsigned char *vendp;
1169 	unsigned char vendor_client[64];
1170 	uint32_t leasetime;
1171 	uint8_t vendor_client_len;
1172 
1173 	ifctx->gotrootpath = 0;
1174 
1175 	bzero((caddr_t) &ifctx->call, sizeof(ifctx->call));
1176 
1177 	/* bootpc part */
1178 	ifctx->call.op = BOOTP_REQUEST; 	/* BOOTREQUEST */
1179 	ifctx->call.htype = 1;			/* 10mb ethernet */
1180 	ifctx->call.hlen = ifctx->sdl->sdl_alen;/* Hardware address length */
1181 	ifctx->call.hops = 0;
1182 	if (bootpc_ifctx_isunresolved(ifctx) != 0)
1183 		ifctx->xid++;
1184 	ifctx->call.xid = txdr_unsigned(ifctx->xid);
1185 	bcopy(LLADDR(ifctx->sdl), &ifctx->call.chaddr, ifctx->sdl->sdl_alen);
1186 
1187 	vendp = ifctx->call.vend;
1188 	*vendp++ = 99;		/* RFC1048 cookie */
1189 	*vendp++ = 130;
1190 	*vendp++ = 83;
1191 	*vendp++ = 99;
1192 	*vendp++ = TAG_MAXMSGSIZE;
1193 	*vendp++ = 2;
1194 	*vendp++ = (sizeof(struct bootp_packet) >> 8) & 255;
1195 	*vendp++ = sizeof(struct bootp_packet) & 255;
1196 
1197 	snprintf(vendor_client, sizeof(vendor_client), "%s:%s:%s",
1198 		ostype, MACHINE, osrelease);
1199 	vendor_client_len = strlen(vendor_client);
1200 	*vendp++ = TAG_VENDOR_INDENTIFIER;
1201 	*vendp++ = vendor_client_len;
1202 	memcpy(vendp, vendor_client, vendor_client_len);
1203 	vendp += vendor_client_len;
1204 	ifctx->dhcpquerytype = DHCP_NOMSG;
1205 	switch (ifctx->state) {
1206 	case IF_DHCP_UNRESOLVED:
1207 		*vendp++ = TAG_DHCP_MSGTYPE;
1208 		*vendp++ = 1;
1209 		*vendp++ = DHCP_DISCOVER;
1210 		ifctx->dhcpquerytype = DHCP_DISCOVER;
1211 		ifctx->gotdhcpserver = 0;
1212 		break;
1213 	case IF_DHCP_OFFERED:
1214 		*vendp++ = TAG_DHCP_MSGTYPE;
1215 		*vendp++ = 1;
1216 		*vendp++ = DHCP_REQUEST;
1217 		ifctx->dhcpquerytype = DHCP_REQUEST;
1218 		*vendp++ = TAG_DHCP_REQ_ADDR;
1219 		*vendp++ = 4;
1220 		memcpy(vendp, &ifctx->reply.yiaddr, 4);
1221 		vendp += 4;
1222 		if (ifctx->gotdhcpserver != 0) {
1223 			*vendp++ = TAG_DHCP_SERVERID;
1224 			*vendp++ = 4;
1225 			memcpy(vendp, &ifctx->dhcpserver, 4);
1226 			vendp += 4;
1227 		}
1228 		*vendp++ = TAG_DHCP_LEASETIME;
1229 		*vendp++ = 4;
1230 		leasetime = htonl(300);
1231 		memcpy(vendp, &leasetime, 4);
1232 		vendp += 4;
1233 		break;
1234 	default:
1235 		break;
1236 	}
1237 	*vendp = TAG_END;
1238 
1239 	ifctx->call.secs = 0;
1240 	ifctx->call.flags = htons(0x8000); /* We need a broadcast answer */
1241 }
1242 
1243 static int
bootpc_hascookie(struct bootp_packet * bp)1244 bootpc_hascookie(struct bootp_packet *bp)
1245 {
1246 
1247 	return (bp->vend[0] == 99 && bp->vend[1] == 130 &&
1248 		bp->vend[2] == 83 && bp->vend[3] == 99);
1249 }
1250 
1251 static void
bootpc_tag_helper(struct bootpc_tagcontext * tctx,unsigned char * start,int len,int tag)1252 bootpc_tag_helper(struct bootpc_tagcontext *tctx,
1253     unsigned char *start, int len, int tag)
1254 {
1255 	unsigned char *j;
1256 	unsigned char *ej;
1257 	unsigned char code;
1258 
1259 	if (tctx->badtag != 0 || tctx->badopt != 0)
1260 		return;
1261 
1262 	j = start;
1263 	ej = j + len;
1264 
1265 	while (j < ej) {
1266 		code = *j++;
1267 		if (code == TAG_PAD)
1268 			continue;
1269 		if (code == TAG_END)
1270 			return;
1271 		if (j >= ej || j + *j + 1 > ej) {
1272 			tctx->badopt = 1;
1273 			return;
1274 		}
1275 		len = *j++;
1276 		if (code == tag) {
1277 			if (tctx->taglen + len > TAG_MAXLEN) {
1278 				tctx->badtag = 1;
1279 				return;
1280 			}
1281 			tctx->foundopt = 1;
1282 			if (len > 0)
1283 				memcpy(tctx->buf + tctx->taglen,
1284 				       j, len);
1285 			tctx->taglen += len;
1286 		}
1287 		if (code == TAG_OVERLOAD)
1288 			tctx->overload = *j;
1289 
1290 		j += len;
1291 	}
1292 }
1293 
1294 static unsigned char *
bootpc_tag(struct bootpc_tagcontext * tctx,struct bootp_packet * bp,int len,int tag)1295 bootpc_tag(struct bootpc_tagcontext *tctx,
1296     struct bootp_packet *bp, int len, int tag)
1297 {
1298 	tctx->overload = 0;
1299 	tctx->badopt = 0;
1300 	tctx->badtag = 0;
1301 	tctx->foundopt = 0;
1302 	tctx->taglen = 0;
1303 
1304 	if (bootpc_hascookie(bp) == 0)
1305 		return NULL;
1306 
1307 	bootpc_tag_helper(tctx, &bp->vend[4],
1308 			  (unsigned char *) bp + len - &bp->vend[4], tag);
1309 
1310 	if ((tctx->overload & OVERLOAD_FILE) != 0)
1311 		bootpc_tag_helper(tctx,
1312 				  (unsigned char *) bp->file,
1313 				  sizeof(bp->file),
1314 				  tag);
1315 	if ((tctx->overload & OVERLOAD_SNAME) != 0)
1316 		bootpc_tag_helper(tctx,
1317 				  (unsigned char *) bp->sname,
1318 				  sizeof(bp->sname),
1319 				  tag);
1320 
1321 	if (tctx->badopt != 0 || tctx->badtag != 0 || tctx->foundopt == 0)
1322 		return NULL;
1323 	tctx->buf[tctx->taglen] = '\0';
1324 	return tctx->buf;
1325 }
1326 
1327 static void
bootpc_decode_reply(struct nfsv3_diskless * nd,struct bootpc_ifcontext * ifctx,struct bootpc_globalcontext * gctx)1328 bootpc_decode_reply(struct nfsv3_diskless *nd, struct bootpc_ifcontext *ifctx,
1329     struct bootpc_globalcontext *gctx)
1330 {
1331 	char *p, *s;
1332 
1333 	ifctx->gotgw = 0;
1334 	ifctx->gotnetmask = 0;
1335 
1336 	clear_sinaddr(&ifctx->myaddr);
1337 	clear_sinaddr(&ifctx->netmask);
1338 	clear_sinaddr(&ifctx->gw);
1339 
1340 	ifctx->myaddr.sin_addr = ifctx->reply.yiaddr;
1341 
1342 	printf("%s at ", ifctx->ireq.ifr_name);
1343 	print_sin_addr(&ifctx->myaddr);
1344 	printf(" server ");
1345 	print_in_addr(ifctx->reply.siaddr);
1346 
1347 	ifctx->gw.sin_addr = ifctx->reply.giaddr;
1348 	if (ifctx->reply.giaddr.s_addr != htonl(INADDR_ANY)) {
1349 		printf(" via gateway ");
1350 		print_in_addr(ifctx->reply.giaddr);
1351 	}
1352 
1353 	/* This call used for the side effect (overload flag) */
1354 	(void) bootpc_tag(&gctx->tmptag,
1355 			  &ifctx->reply, ifctx->replylen, TAG_END);
1356 
1357 	if ((gctx->tmptag.overload & OVERLOAD_SNAME) == 0)
1358 		if (ifctx->reply.sname[0] != '\0')
1359 			printf(" server name %s", ifctx->reply.sname);
1360 	if ((gctx->tmptag.overload & OVERLOAD_FILE) == 0)
1361 		if (ifctx->reply.file[0] != '\0')
1362 			printf(" boot file %s", ifctx->reply.file);
1363 
1364 	printf("\n");
1365 
1366 	p = bootpc_tag(&gctx->tag, &ifctx->reply, ifctx->replylen,
1367 		       TAG_SUBNETMASK);
1368 	if (p != NULL) {
1369 		if (gctx->tag.taglen != 4)
1370 			panic("bootpc: subnet mask len is %d",
1371 			      gctx->tag.taglen);
1372 		bcopy(p, &ifctx->netmask.sin_addr, 4);
1373 		ifctx->gotnetmask = 1;
1374 		printf("subnet mask ");
1375 		print_sin_addr(&ifctx->netmask);
1376 		printf(" ");
1377 	}
1378 
1379 	p = bootpc_tag(&gctx->tag, &ifctx->reply, ifctx->replylen,
1380 		       TAG_ROUTERS);
1381 	if (p != NULL) {
1382 		/* Routers */
1383 		if (gctx->tag.taglen % 4)
1384 			panic("bootpc: Router Len is %d", gctx->tag.taglen);
1385 		if (gctx->tag.taglen > 0) {
1386 			bcopy(p, &ifctx->gw.sin_addr, 4);
1387 			printf("router ");
1388 			print_sin_addr(&ifctx->gw);
1389 			printf(" ");
1390 			ifctx->gotgw = 1;
1391 			gctx->gotgw = 1;
1392 		}
1393 	}
1394 
1395 	/*
1396 	 * Choose a root filesystem.  If a value is forced in the environment
1397 	 * and it contains "nfs:", use it unconditionally.  Otherwise, if the
1398 	 * kernel is compiled with the ROOTDEVNAME option, then use it if:
1399 	 *  - The server doesn't provide a pathname.
1400 	 *  - The boothowto flags include RB_DFLTROOT (user said to override
1401 	 *    the server value).
1402 	 */
1403 	p = NULL;
1404 	if ((s = kern_getenv("vfs.root.mountfrom")) != NULL) {
1405 		if ((p = strstr(s, "nfs:")) != NULL)
1406 			p = strdup(p + 4, M_TEMP);
1407 		freeenv(s);
1408 	}
1409 	if (p == NULL) {
1410 		p = bootpc_tag(&gctx->tag, &ifctx->reply, ifctx->replylen,
1411 		       TAG_ROOT);
1412 		if (p != NULL)
1413 			ifctx->gotrootpath = 1;
1414 	}
1415 #ifdef ROOTDEVNAME
1416 	if ((p == NULL || (boothowto & RB_DFLTROOT) != 0) &&
1417 	    (p = strstr(ROOTDEVNAME, "nfs:")) != NULL) {
1418 		p += 4;
1419 	}
1420 #endif
1421 	if (p != NULL) {
1422 		if (gctx->setrootfs != NULL) {
1423 			printf("rootfs %s (ignored) ", p);
1424 		} else 	if (setfs(&nd->root_saddr,
1425 				  nd->root_hostnam, p, &ifctx->reply.siaddr)) {
1426 			if (*p == '/') {
1427 				printf("root_server ");
1428 				print_sin_addr(&nd->root_saddr);
1429 				printf(" ");
1430 			}
1431 			printf("rootfs %s ", p);
1432 			gctx->gotrootpath = 1;
1433 			gctx->setrootfs = ifctx;
1434 
1435 			p = bootpc_tag(&gctx->tag, &ifctx->reply,
1436 				       ifctx->replylen,
1437 				       TAG_ROOTOPTS);
1438 			if (p != NULL) {
1439 				mountopts(&nd->root_args, p);
1440 				printf("rootopts %s ", p);
1441 			}
1442 		} else
1443 			panic("Failed to set rootfs to %s", p);
1444 	}
1445 
1446 	p = bootpc_tag(&gctx->tag, &ifctx->reply, ifctx->replylen,
1447 		       TAG_HOSTNAME);
1448 	if (p != NULL) {
1449 		if (gctx->tag.taglen >= MAXHOSTNAMELEN)
1450 			panic("bootpc: hostname >= %d bytes",
1451 			      MAXHOSTNAMELEN);
1452 		if (gctx->sethostname != NULL) {
1453 			printf("hostname %s (ignored) ", p);
1454 		} else {
1455 			strcpy(nd->my_hostnam, p);
1456 			mtx_lock(&prison0.pr_mtx);
1457 			strcpy(prison0.pr_hostname, p);
1458 			mtx_unlock(&prison0.pr_mtx);
1459 			printf("hostname %s ", p);
1460 			gctx->sethostname = ifctx;
1461 		}
1462 	}
1463 	p = bootpc_tag(&gctx->tag, &ifctx->reply, ifctx->replylen,
1464 			TAG_COOKIE);
1465 	if (p != NULL) {        /* store in a sysctl variable */
1466 		int i, l = sizeof(bootp_cookie) - 1;
1467 		for (i = 0; i < l && p[i] != '\0'; i++)
1468 			bootp_cookie[i] = p[i];
1469 		p[i] = '\0';
1470 	}
1471 
1472 	p = bootpc_tag(&gctx->tag, &ifctx->reply, ifctx->replylen,
1473 		       TAG_INTF_MTU);
1474 	if (p != NULL) {
1475 		ifctx->mtu = be16dec(p);
1476 	}
1477 
1478 	printf("\n");
1479 
1480 	if (ifctx->gotnetmask == 0) {
1481 		/*
1482 		 * If there is no netmask, use historical default,
1483 		 * but we really need the right mask from the server.
1484 		 */
1485 		printf("%s: no netmask received!\n", ifctx->ireq.ifr_name);
1486 		if (IN_CLASSA(ntohl(ifctx->myaddr.sin_addr.s_addr)))
1487 			ifctx->netmask.sin_addr.s_addr = htonl(IN_CLASSA_NET);
1488 		else if (IN_CLASSB(ntohl(ifctx->myaddr.sin_addr.s_addr)))
1489 			ifctx->netmask.sin_addr.s_addr = htonl(IN_CLASSB_NET);
1490 		else
1491 			ifctx->netmask.sin_addr.s_addr = htonl(IN_CLASSC_NET);
1492 	}
1493 }
1494 
1495 static u_int
bootpc_init_ifa_cb(void * arg,struct ifaddr * ifa,u_int count)1496 bootpc_init_ifa_cb(void *arg, struct ifaddr *ifa, u_int count)
1497 {
1498 	struct sockaddr_dl *sdl = (struct sockaddr_dl *)ifa->ifa_addr;
1499 
1500 	if (count != 0)
1501 		return (0);
1502 
1503 	if (sdl->sdl_type != IFT_ETHER)
1504 		return (0);
1505 
1506 	*(struct sockaddr_dl **)arg = sdl;
1507 
1508 	return (1);
1509 }
1510 
1511 void
bootpc_init(void)1512 bootpc_init(void)
1513 {
1514 	struct epoch_tracker et;
1515 	struct bootpc_ifcontext *ifctx = NULL;	/* Interface BOOTP contexts */
1516 	struct bootpc_globalcontext *gctx; 	/* Global BOOTP context */
1517 	struct sockaddr_dl *sdl;
1518 	struct if_iter iter;
1519 	if_t ifp;
1520 	int error;
1521 #ifndef BOOTP_WIRED_TO
1522 	int ifcnt;
1523 #endif
1524 	struct nfsv3_diskless *nd;
1525 	struct thread *td;
1526 	int timeout;
1527 	int delay;
1528 	char *s;
1529 
1530 	timeout = BOOTP_IFACE_WAIT_TIMEOUT * hz;
1531 	delay = hz / 10;
1532 
1533 	nd = &nfsv3_diskless;
1534 	td = curthread;
1535 
1536 	/*
1537 	 * If already filled in, don't touch it here
1538 	 */
1539 	if (nfs_diskless_valid != 0)
1540 		return;
1541 
1542 	/*
1543 	 * If "vfs.root.mountfrom" is set and the value is something other
1544 	 * than "nfs:", it means the user doesn't want to mount root via nfs,
1545 	 * there's no reason to continue with bootpc
1546 	 */
1547 	if ((s = kern_getenv("vfs.root.mountfrom")) != NULL) {
1548 		if ((strncmp(s, "nfs:", 4)) != 0) {
1549 			printf("%s: vfs.root.mountfrom set to %s. "
1550 			       "BOOTP aborted.\n", __func__, s);
1551 			freeenv(s);
1552 			return;
1553 		}
1554 		freeenv(s);
1555 	}
1556 
1557 	gctx = malloc(sizeof(*gctx), M_TEMP, M_WAITOK | M_ZERO);
1558 	STAILQ_INIT(&gctx->interfaces);
1559 	gctx->xid = ~0xFFFF;
1560 	gctx->starttime = time_second;
1561 
1562 	/*
1563 	 * If ROOTDEVNAME is defined or vfs.root.mountfrom is set then we have
1564 	 * root-path overrides that can potentially let us boot even if we don't
1565 	 * get a root path from the server, so we can treat that as a non-error.
1566 	 */
1567 #ifdef ROOTDEVNAME
1568 	gctx->any_root_overrides = 1;
1569 #else
1570 	gctx->any_root_overrides = testenv("vfs.root.mountfrom");
1571 #endif
1572 
1573 	/*
1574 	 * Find a network interface.
1575 	 */
1576 	CURVNET_SET(TD_TO_VNET(td));
1577 #ifdef BOOTP_WIRED_TO
1578 	printf("%s: wired to interface '%s'\n", __func__,
1579 	       __XSTRING(BOOTP_WIRED_TO));
1580 	allocifctx(gctx);
1581 #else
1582 	/*
1583 	 * Preallocate interface context storage, if another interface
1584 	 * attaches and wins the race, it won't be eligible for bootp.
1585 	 */
1586 	ifcnt = 0;
1587 	NET_EPOCH_ENTER(et);
1588 	for (if_t ifp = if_iter_start(&iter); ifp != NULL; ifp = if_iter_next(&iter)) {
1589 		if ((if_getflags(ifp) &
1590 		    (IFF_LOOPBACK | IFF_POINTOPOINT | IFF_BROADCAST)) ==
1591 		    IFF_BROADCAST)
1592 			ifcnt++;
1593 	}
1594 	if_iter_finish(&iter);
1595 	NET_EPOCH_EXIT(et);
1596 	if (ifcnt == 0) {
1597 		printf("WARNING: BOOTP found no eligible network interfaces, skipping!\n");
1598 		goto out;
1599 	}
1600 
1601 	for (; ifcnt > 0; ifcnt--)
1602 		allocifctx(gctx);
1603 #endif
1604 
1605 retry:
1606 	ifctx = STAILQ_FIRST(&gctx->interfaces);
1607 	NET_EPOCH_ENTER(et);
1608 	for (ifp = if_iter_start(&iter); ifp != NULL; ifp = if_iter_next(&iter)) {
1609 		if (ifctx == NULL)
1610 			break;
1611 #ifdef BOOTP_WIRED_TO
1612 		if (strcmp(if_name(ifp), __XSTRING(BOOTP_WIRED_TO)) != 0)
1613 			continue;
1614 #else
1615 		if ((if_getflags(ifp) &
1616 		     (IFF_LOOPBACK | IFF_POINTOPOINT | IFF_BROADCAST)) !=
1617 		    IFF_BROADCAST)
1618 			break;
1619 		switch (if_getalloctype(ifp)) {
1620 			case IFT_ETHER:
1621 				break;
1622 			default:
1623 				continue;
1624 		}
1625 #endif
1626 		strlcpy(ifctx->ireq.ifr_name, if_name(ifp),
1627 		    sizeof(ifctx->ireq.ifr_name));
1628 		ifctx->ifp = ifp;
1629 
1630 		/* Get HW address */
1631 		sdl = NULL;
1632 		if_foreach_addr_type(ifp, AF_LINK, bootpc_init_ifa_cb, &sdl);
1633 		if (sdl == NULL)
1634 			panic("bootpc: Unable to find HW address for %s",
1635 			    ifctx->ireq.ifr_name);
1636 		ifctx->sdl = sdl;
1637 
1638 		ifctx = STAILQ_NEXT(ifctx, next);
1639 	}
1640 	if_iter_finish(&iter);
1641 	NET_EPOCH_EXIT(et);
1642 	CURVNET_RESTORE();
1643 
1644 	if (STAILQ_EMPTY(&gctx->interfaces) ||
1645 	    STAILQ_FIRST(&gctx->interfaces)->ifp == NULL) {
1646 		if (timeout > 0) {
1647 			pause("bootpc", delay);
1648 			timeout -= delay;
1649 			goto retry;
1650 		}
1651 #ifdef BOOTP_WIRED_TO
1652 		panic("%s: Could not find interface specified "
1653 		      "by BOOTP_WIRED_TO: "
1654 		      __XSTRING(BOOTP_WIRED_TO), __func__);
1655 #else
1656 		panic("%s: no suitable interface", __func__);
1657 #endif
1658 	}
1659 
1660 	error = socreate(AF_INET, &bootp_so, SOCK_DGRAM, 0, td->td_ucred, td);
1661 	if (error != 0)
1662 		panic("%s: socreate, error=%d", __func__, error);
1663 
1664 	STAILQ_FOREACH(ifctx, &gctx->interfaces, next)
1665 		bootpc_fakeup_interface(ifctx, td);
1666 
1667 	STAILQ_FOREACH(ifctx, &gctx->interfaces, next)
1668 		bootpc_compose_query(ifctx, td);
1669 
1670 	error = bootpc_call(gctx, td);
1671 	if (error != 0) {
1672 		printf("BOOTP call failed\n");
1673 	}
1674 
1675 	mountopts(&nd->root_args, NULL);
1676 
1677 	STAILQ_FOREACH(ifctx, &gctx->interfaces, next)
1678 		if (bootpc_ifctx_isresolved(ifctx) != 0)
1679 			bootpc_decode_reply(nd, ifctx, gctx);
1680 
1681 #ifdef BOOTP_NFSROOT
1682 	if (gctx->gotrootpath == 0 && gctx->any_root_overrides == 0)
1683 		panic("bootpc: No root path offered");
1684 #endif
1685 
1686 	STAILQ_FOREACH(ifctx, &gctx->interfaces, next)
1687 		bootpc_adjust_interface(ifctx, gctx, td);
1688 
1689 	soclose(bootp_so);
1690 
1691 	STAILQ_FOREACH(ifctx, &gctx->interfaces, next)
1692 		if (ifctx->gotrootpath != 0)
1693 			break;
1694 	if (ifctx == NULL) {
1695 		STAILQ_FOREACH(ifctx, &gctx->interfaces, next)
1696 			if (bootpc_ifctx_isresolved(ifctx) != 0)
1697 				break;
1698 	}
1699 	if (ifctx == NULL)
1700 		goto out;
1701 
1702 	if (gctx->gotrootpath != 0) {
1703 		struct epoch_tracker et;
1704 
1705 		kern_setenv("boot.netif.name", if_name(ifctx->ifp));
1706 
1707 		NET_EPOCH_ENTER(et);
1708 		bootpc_add_default_route(ifctx);
1709 		NET_EPOCH_EXIT(et);
1710 		error = md_mount(&nd->root_saddr, nd->root_hostnam,
1711 				 nd->root_fh, &nd->root_fhsize,
1712 				 &nd->root_args, td);
1713 		NET_EPOCH_ENTER(et);
1714 		bootpc_remove_default_route(ifctx);
1715 		NET_EPOCH_EXIT(et);
1716 		if (error != 0) {
1717 			if (gctx->any_root_overrides == 0)
1718 				panic("nfs_boot: mount root, error=%d", error);
1719 			else
1720 				goto out;
1721 		}
1722 		rootdevnames[0] = "nfs:";
1723 		nfs_diskless_valid = 3;
1724 	}
1725 
1726 	strcpy(nd->myif.ifra_name, ifctx->ireq.ifr_name);
1727 	bcopy(&ifctx->myaddr, &nd->myif.ifra_addr, sizeof(ifctx->myaddr));
1728 	bcopy(&ifctx->myaddr, &nd->myif.ifra_broadaddr, sizeof(ifctx->myaddr));
1729 	((struct sockaddr_in *) &nd->myif.ifra_broadaddr)->sin_addr.s_addr =
1730 		ifctx->myaddr.sin_addr.s_addr |
1731 		~ ifctx->netmask.sin_addr.s_addr;
1732 	bcopy(&ifctx->netmask, &nd->myif.ifra_mask, sizeof(ifctx->netmask));
1733 	bcopy(&ifctx->gw, &nd->mygateway, sizeof(ifctx->gw));
1734 
1735 out:
1736 	while((ifctx = STAILQ_FIRST(&gctx->interfaces)) != NULL) {
1737 		STAILQ_REMOVE_HEAD(&gctx->interfaces, next);
1738 		free(ifctx, M_TEMP);
1739 	}
1740 	free(gctx, M_TEMP);
1741 }
1742 
1743 /*
1744  * RPC: mountd/mount
1745  * Given a server pathname, get an NFS file handle.
1746  * Also, sets sin->sin_port to the NFS service port.
1747  */
1748 static int
md_mount(struct sockaddr_in * mdsin,char * path,u_char * fhp,int * fhsizep,struct nfs_args * args,struct thread * td)1749 md_mount(struct sockaddr_in *mdsin, char *path, u_char *fhp, int *fhsizep,
1750     struct nfs_args *args, struct thread *td)
1751 {
1752 	struct mbuf *m;
1753 	int error;
1754 	int authunixok;
1755 	int authcount;
1756 	int authver;
1757 
1758 #define	RPCPROG_MNT	100005
1759 #define	RPCMNT_VER1	1
1760 #define RPCMNT_VER3	3
1761 #define	RPCMNT_MOUNT	1
1762 #define	AUTH_SYS	1		/* unix style (uid, gids) */
1763 #define AUTH_UNIX	AUTH_SYS
1764 
1765 	/* XXX honor v2/v3 flags in args->flags? */
1766 #ifdef BOOTP_NFSV3
1767 	/* First try NFS v3 */
1768 	/* Get port number for MOUNTD. */
1769 	error = krpc_portmap(mdsin, RPCPROG_MNT, RPCMNT_VER3,
1770 			     &mdsin->sin_port, td);
1771 	if (error == 0) {
1772 		m = xdr_string_encode(path, strlen(path));
1773 
1774 		/* Do RPC to mountd. */
1775 		error = krpc_call(mdsin, RPCPROG_MNT, RPCMNT_VER3,
1776 				  RPCMNT_MOUNT, &m, NULL, td);
1777 	}
1778 	if (error == 0) {
1779 		args->flags |= NFSMNT_NFSV3;
1780 	} else {
1781 #endif
1782 		/* Fallback to NFS v2 */
1783 
1784 		/* Get port number for MOUNTD. */
1785 		error = krpc_portmap(mdsin, RPCPROG_MNT, RPCMNT_VER1,
1786 				     &mdsin->sin_port, td);
1787 		if (error != 0)
1788 			return error;
1789 
1790 		m = xdr_string_encode(path, strlen(path));
1791 
1792 		/* Do RPC to mountd. */
1793 		error = krpc_call(mdsin, RPCPROG_MNT, RPCMNT_VER1,
1794 				  RPCMNT_MOUNT, &m, NULL, td);
1795 		if (error != 0)
1796 			return error;	/* message already freed */
1797 
1798 #ifdef BOOTP_NFSV3
1799 	}
1800 #endif
1801 
1802 	if (xdr_int_decode(&m, &error) != 0 || error != 0)
1803 		goto bad;
1804 
1805 	if ((args->flags & NFSMNT_NFSV3) != 0) {
1806 		if (xdr_int_decode(&m, fhsizep) != 0 ||
1807 		    *fhsizep > NFSX_V3FHMAX ||
1808 		    *fhsizep <= 0)
1809 			goto bad;
1810 	} else
1811 		*fhsizep = NFSX_V2FH;
1812 
1813 	if (xdr_opaque_decode(&m, fhp, *fhsizep) != 0)
1814 		goto bad;
1815 
1816 	if (args->flags & NFSMNT_NFSV3) {
1817 		if (xdr_int_decode(&m, &authcount) != 0)
1818 			goto bad;
1819 		authunixok = 0;
1820 		if (authcount < 0 || authcount > 100)
1821 			goto bad;
1822 		while (authcount > 0) {
1823 			if (xdr_int_decode(&m, &authver) != 0)
1824 				goto bad;
1825 			if (authver == AUTH_UNIX)
1826 				authunixok = 1;
1827 			authcount--;
1828 		}
1829 		if (authunixok == 0)
1830 			goto bad;
1831 	}
1832 
1833 	/* Set port number for NFS use. */
1834 	error = krpc_portmap(mdsin, NFS_PROG,
1835 			     (args->flags &
1836 			      NFSMNT_NFSV3) ? NFS_VER3 : NFS_VER2,
1837 			     &mdsin->sin_port, td);
1838 
1839 	goto out;
1840 
1841 bad:
1842 	error = EBADRPC;
1843 
1844 out:
1845 	m_freem(m);
1846 	return error;
1847 }
1848 
1849 SYSINIT(bootp_rootconf, SI_SUB_ROOT_CONF, SI_ORDER_FIRST, bootpc_init, NULL);
1850