xref: /netbsd-src/sys/nfs/nfs_boot.c (revision 7c7c171d130af9949261bc7dce2150a03c3d239c)
1 /*	$NetBSD: nfs_boot.c,v 1.44 1998/03/01 02:24:27 fvdl Exp $	*/
2 
3 /*-
4  * Copyright (c) 1995, 1997 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Adam Glass and Gordon W. Ross.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *        This product includes software developed by the NetBSD
21  *        Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 /*
40  * Support for NFS diskless booting, specifically getting information
41  * about where to mount root from, what pathnames, etc.
42  */
43 
44 #include "opt_nfs_boot.h"
45 
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/kernel.h>
49 #include <sys/conf.h>
50 #include <sys/device.h>
51 #include <sys/ioctl.h>
52 #include <sys/proc.h>
53 #include <sys/mount.h>
54 #include <sys/mbuf.h>
55 #include <sys/reboot.h>
56 #include <sys/socket.h>
57 #include <sys/socketvar.h>
58 
59 #include <net/if.h>
60 #include <net/route.h>
61 #include <net/if_ether.h>
62 #include <net/if_types.h>
63 
64 #include <netinet/in.h>
65 #include <netinet/if_inarp.h>
66 
67 #include <nfs/rpcv2.h>
68 #include <nfs/krpc.h>
69 #include <nfs/xdr_subs.h>
70 
71 #include <nfs/nfsproto.h>
72 #include <nfs/nfs.h>
73 #include <nfs/nfsmount.h>
74 #include <nfs/nfsdiskless.h>
75 
76 /*
77  * There are two implementations of NFS diskless boot.
78  * One implementation uses BOOTP (RFC951, RFC1048),
79  * the other uses Sun RPC/bootparams.  See the files:
80  *    nfs_bootp.c:   BOOTP (RFC951, RFC1048)
81  *    nfs_bootsun.c: Sun RPC/bootparams
82  */
83 #if defined(NFS_BOOT_BOOTP) || defined(NFS_BOOT_DHCP)
84 int nfs_boot_rfc951 = 1; /* BOOTP enabled (default) */
85 #endif
86 #ifdef NFS_BOOT_BOOTPARAM
87 int nfs_boot_bootparam = 1; /* BOOTPARAM enabled (default) */
88 #endif
89 
90 /* mountd RPC */
91 static int md_mount __P((struct sockaddr_in *mdsin, char *path,
92 	struct nfs_args *argp));
93 
94 static void nfs_boot_defrt __P((struct in_addr *));
95 static  int nfs_boot_getfh __P((struct nfs_dlmount *ndm));
96 
97 
98 /*
99  * Called with an empty nfs_diskless struct to be filled in.
100  * Find an interface, determine its ip address (etc.) and
101  * save all the boot parameters in the nfs_diskless struct.
102  */
103 int
104 nfs_boot_init(nd, procp)
105 	struct nfs_diskless *nd;
106 	struct proc *procp;
107 {
108 	struct ifnet *ifp;
109 	int error;
110 
111 	/*
112 	 * Find the network interface.
113 	 */
114 	ifp = ifunit(root_device->dv_xname);
115 	if (ifp == NULL) {
116 		printf("nfs_boot: '%s' not found\n",
117 		       root_device->dv_xname);
118 		return (ENXIO);
119 	}
120 
121 	error = EADDRNOTAVAIL; /* ??? */
122 #if defined(NFS_BOOT_BOOTP) || defined(NFS_BOOT_DHCP)
123 	if (nfs_boot_rfc951) {
124 #if defined(NFS_BOOT_DHCP)
125 		printf("nfs_boot: trying DHCP/BOOTP\n");
126 #else
127 		printf("nfs_boot: trying BOOTP\n");
128 #endif
129 		error = nfs_bootdhcp(ifp, nd, procp);
130 		if (!error)
131 			goto ok;
132 	}
133 #endif
134 #ifdef NFS_BOOT_BOOTPARAM
135 	if (nfs_boot_bootparam) {
136 		printf("nfs_boot: trying RARP (and RPC/bootparam)\n");
137 		error = nfs_bootparam(ifp, nd, procp);
138 		if (!error)
139 			goto ok;
140 	}
141 #endif
142 	if (0) goto ok; /* XXX stupid gcc */
143 	return (error);
144 
145 ok:
146 	/*
147 	 * If the gateway address is set, add a default route.
148 	 * (The mountd RPCs may go across a gateway.)
149 	 */
150 	if (nd->nd_gwip.s_addr)
151 		nfs_boot_defrt(&nd->nd_gwip);
152 
153 	/*
154 	 * Now fetch the NFS file handles as appropriate.
155 	 */
156 	error = nfs_boot_getfh(&nd->nd_root);
157 	if (error)
158 		return (error);
159 
160 	return (error);
161 }
162 
163 int nfs_boot_setrecvtimo(so)
164 struct socket *so;
165 {
166 	struct mbuf *m;
167 	struct timeval *tv;
168 
169 	m = m_get(M_WAIT, MT_SOOPTS);
170 	tv = mtod(m, struct timeval *);
171 	m->m_len = sizeof(*tv);
172 	tv->tv_sec = 1;
173 	tv->tv_usec = 0;
174 	return(sosetopt(so, SOL_SOCKET, SO_RCVTIMEO, m));
175 }
176 
177 int nfs_boot_enbroadcast(so)
178 struct socket *so;
179 {
180 	struct mbuf *m;
181 	int32_t *on;
182 
183 	m = m_get(M_WAIT, MT_SOOPTS);
184 	on = mtod(m, int32_t *);
185 	m->m_len = sizeof(*on);
186 	*on = 1;
187 	return(sosetopt(so, SOL_SOCKET, SO_BROADCAST, m));
188 }
189 
190 int nfs_boot_sobind_ipport(so, port)
191 struct socket *so;
192 u_int16_t port;
193 {
194 	struct mbuf *m;
195 	struct sockaddr_in *sin;
196 	int error;
197 
198 	m = m_getclr(M_WAIT, MT_SONAME);
199 	sin = mtod(m, struct sockaddr_in *);
200 	sin->sin_len = m->m_len = sizeof(*sin);
201 	sin->sin_family = AF_INET;
202 	sin->sin_addr.s_addr = INADDR_ANY;
203 	sin->sin_port = htons(port);
204 	error = sobind(so, m);
205 	m_freem(m);
206 	return(error);
207 }
208 
209 /*
210  * What is the longest we will wait before re-sending a request?
211  * Note this is also the frequency of "timeout" messages.
212  * The re-send loop counts up linearly to this maximum, so the
213  * first complaint will happen after (1+2+3+4+5)=15 seconds.
214  */
215 #define	MAX_RESEND_DELAY 5	/* seconds */
216 #define TOTAL_TIMEOUT   30	/* seconds */
217 
218 int nfs_boot_sendrecv(so, nam, sndproc, snd, rcvproc, rcv,
219 		      from_p, context)
220 struct socket *so;
221 struct mbuf *nam;
222 int (*sndproc) __P((struct mbuf*, void*, int));
223 struct mbuf *snd;
224 int (*rcvproc) __P((struct mbuf*, void*));
225 struct mbuf **rcv, **from_p;
226 void *context;
227 {
228 	int error, rcvflg, timo, secs, waited;
229 	struct mbuf *m, *from;
230 	struct uio uio;
231 
232 	/* Free at end if not null. */
233 	from = NULL;
234 
235 	/*
236 	 * Send it, repeatedly, until a reply is received,
237 	 * but delay each re-send by an increasing amount.
238 	 * If the delay hits the maximum, start complaining.
239 	 */
240 	waited = timo = 0;
241 send_again:
242 	waited += timo;
243 	if (waited >= TOTAL_TIMEOUT)
244 		return(ETIMEDOUT);
245 
246 	/* Determine new timeout. */
247 	if (timo < MAX_RESEND_DELAY)
248 		timo++;
249 	else
250 		printf("nfs_boot: timeout...\n");
251 
252 	if (sndproc) {
253 		error = (*sndproc)(snd, context, waited);
254 		if (error)
255 			goto out;
256 	}
257 
258 	/* Send request (or re-send). */
259 	m = m_copypacket(snd, M_WAIT);
260 	if (m == NULL) {
261 		error = ENOBUFS;
262 		goto out;
263 	}
264 	error = sosend(so, nam, NULL, m, NULL, 0);
265 	if (error) {
266 		printf("nfs_boot: sosend: %d\n", error);
267 		goto out;
268 	}
269 	m = NULL;
270 
271 	/*
272 	 * Wait for up to timo seconds for a reply.
273 	 * The socket receive timeout was set to 1 second.
274 	 */
275 
276 	secs = timo;
277 	for (;;) {
278 		if (from) {
279 			m_freem(from);
280 			from = NULL;
281 		}
282 		if (m) {
283 			m_freem(m);
284 			m = NULL;
285 		}
286 		uio.uio_resid = 1 << 16; /* ??? */
287 		rcvflg = 0;
288 		error = soreceive(so, &from, &uio, &m, NULL, &rcvflg);
289 		if (error == EWOULDBLOCK) {
290 			if (--secs <= 0)
291 				goto send_again;
292 			continue;
293 		}
294 		if (error)
295 			goto out;
296 #ifdef DIAGNOSTIC
297 		if (!m || !(m->m_flags & M_PKTHDR)
298 		    || (1 << 16) - uio.uio_resid != m->m_pkthdr.len)
299 			panic("nfs_boot_sendrecv: return size");
300 #endif
301 
302 		if ((*rcvproc)(m, context))
303 			continue;
304 
305 		if (rcv)
306 			*rcv = m;
307 		else
308 			m_freem(m);
309 		if (from_p) {
310 			*from_p = from;
311 			from = NULL;
312 		}
313 		break;
314 	}
315 out:
316 	if (from) m_freem(from);
317 	return(error);
318 }
319 
320 /*
321  * Install a default route to the passed IP address.
322  */
323 static void
324 nfs_boot_defrt(gw_ip)
325 	struct in_addr *gw_ip;
326 {
327 	struct sockaddr dst, gw, mask;
328 	struct sockaddr_in *sin;
329 	int error;
330 
331 	/* Destination: (default) */
332 	bzero((caddr_t)&dst, sizeof(dst));
333 	dst.sa_len = sizeof(dst);
334 	dst.sa_family = AF_INET;
335 	/* Gateway: */
336 	bzero((caddr_t)&gw, sizeof(gw));
337 	sin = (struct sockaddr_in *)&gw;
338 	sin->sin_len = sizeof(*sin);
339 	sin->sin_family = AF_INET;
340 	sin->sin_addr.s_addr = gw_ip->s_addr;
341 	/* Mask: (zero length) */
342 	/* XXX - Just pass a null pointer? */
343 	bzero(&mask, sizeof(mask));
344 
345 	/* add, dest, gw, mask, flags, 0 */
346 	error = rtrequest(RTM_ADD, &dst, &gw, &mask,
347 					  (RTF_UP | RTF_GATEWAY | RTF_STATIC), NULL);
348 	if (error) {
349 		printf("nfs_boot: add route, error=%d\n", error);
350 		error = 0;
351 	}
352 }
353 
354 /*
355  * Get an initial NFS file handle using Sun RPC/mountd.
356  * Separate function because we used to call it twice.
357  * (once for root and once for swap)
358  */
359 static int
360 nfs_boot_getfh(ndm)
361 	struct nfs_dlmount *ndm;	/* output */
362 {
363 	struct nfs_args *args;
364 	struct sockaddr_in *sin;
365 	char *pathname;
366 	int error;
367 	u_int16_t port;
368 
369 	args = &ndm->ndm_args;
370 
371 	/* Initialize mount args. */
372 	bzero((caddr_t) args, sizeof(*args));
373 	args->addr     = &ndm->ndm_saddr;
374 	args->addrlen  = args->addr->sa_len;
375 #ifdef NFS_BOOT_TCP
376 	args->sotype   = SOCK_STREAM;
377 #else
378 	args->sotype   = SOCK_DGRAM;
379 #endif
380 	args->fh       = ndm->ndm_fh;
381 	args->hostname = ndm->ndm_host;
382 	args->flags    = NFSMNT_RESVPORT | NFSMNT_NFSV3;
383 
384 #ifdef	NFS_BOOT_OPTIONS
385 	args->flags    |= NFS_BOOT_OPTIONS;
386 #endif
387 #ifdef	NFS_BOOT_RWSIZE
388 	/*
389 	 * Reduce rsize,wsize for interfaces that consistently
390 	 * drop fragments of long UDP messages.  (i.e. wd8003).
391 	 * You can always change these later via remount.
392 	 */
393 	args->flags   |= NFSMNT_WSIZE | NFSMNT_RSIZE;
394 	args->wsize    = NFS_BOOT_RWSIZE;
395 	args->rsize    = NFS_BOOT_RWSIZE;
396 #endif
397 
398 	/*
399 	 * Find the pathname part of the "server:pathname"
400 	 * string left in ndm->ndm_host by nfs_boot_init.
401 	 */
402 	pathname = strchr(ndm->ndm_host, ':');
403 	if (pathname == 0) {
404 		printf("nfs_boot: getfh - no pathname\n");
405 		return (EIO);
406 	}
407 	pathname++;
408 
409 	/*
410 	 * Get file handle using RPC to mountd/mount
411 	 */
412 	sin = (struct sockaddr_in *)&ndm->ndm_saddr;
413 	error = md_mount(sin, pathname, args);
414 	if (error) {
415 		printf("nfs_boot: mountd `%s', error=%d\n",
416 		       ndm->ndm_host, error);
417 		return (error);
418 	}
419 
420 	/* Set port number for NFS use. */
421 	/* XXX: NFS port is always 2049, right? */
422 #ifdef NFS_BOOT_TCP
423 retry:
424 #endif
425 	error = krpc_portmap(sin, NFS_PROG,
426 		    (args->flags & NFSMNT_NFSV3) ? NFS_VER3 : NFS_VER2,
427 		    (args->sotype == SOCK_STREAM) ? IPPROTO_TCP : IPPROTO_UDP,
428 		    &port);
429 	if (port == htons(0))
430 		error = EIO;
431 	if (error) {
432 #ifdef NFS_BOOT_TCP
433 		if (args->sotype == SOCK_STREAM) {
434 			args->sotype = SOCK_DGRAM;
435 			goto retry;
436 		}
437 #endif
438 		printf("nfs_boot: portmap NFS, error=%d\n", error);
439 		return (error);
440 	}
441 	sin->sin_port = port;
442 	return (0);
443 }
444 
445 
446 /*
447  * RPC: mountd/mount
448  * Given a server pathname, get an NFS file handle.
449  * Also, sets sin->sin_port to the NFS service port.
450  */
451 static int
452 md_mount(mdsin, path, argp)
453 	struct sockaddr_in *mdsin;		/* mountd server address */
454 	char *path;
455 	struct nfs_args *argp;
456 {
457 	/* The RPC structures */
458 	struct rdata {
459 		u_int32_t errno;
460 		union {
461 			u_int8_t  v2fh[NFSX_V2FH];
462 			struct {
463 				u_int32_t fhlen;
464 				u_int8_t  fh[1];
465 			} v3fh;
466 		} fh;
467 	} *rdata;
468 	struct mbuf *m;
469 	u_int8_t *fh;
470 	int minlen, error;
471 	int mntver;
472 
473 	mntver = (argp->flags & NFSMNT_NFSV3) ? 3 : 2;
474 	do {
475 		/*
476 		 * Get port number for MOUNTD.
477 		 */
478 		error = krpc_portmap(mdsin, RPCPROG_MNT, mntver,
479 		                    IPPROTO_UDP, &mdsin->sin_port);
480 		if (error)
481 			continue;
482 
483 		/* This mbuf is consumed by krpc_call. */
484 		m = xdr_string_encode(path, strlen(path));
485 		if (m == NULL)
486 			return ENOMEM;
487 
488 		/* Do RPC to mountd. */
489 		error = krpc_call(mdsin, RPCPROG_MNT, mntver,
490 		                  RPCMNT_MOUNT, &m, NULL);
491 		if (error != EPROGMISMATCH)
492 			break;
493 		/* Try lower version of mountd. */
494 	} while (--mntver >= 1);
495 	if (error) {
496 		printf("nfs_boot: mountd error=%d\n", error);
497 		return error;
498 	}
499 	if (mntver != 3)
500 		argp->flags &= ~NFSMNT_NFSV3;
501 
502 	/* The reply might have only the errno. */
503 	if (m->m_len < 4)
504 		goto bad;
505 	/* Have at least errno, so check that. */
506 	rdata = mtod(m, struct rdata *);
507 	error = fxdr_unsigned(u_int32_t, rdata->errno);
508 	if (error)
509 		goto out;
510 
511 	/* Have errno==0, so the fh must be there. */
512 	if (mntver == 3) {
513 		argp->fhsize   = fxdr_unsigned(u_int32_t, rdata->fh.v3fh.fhlen);
514 		if (argp->fhsize > NFSX_V3FHMAX)
515 			goto bad;
516 		minlen = 2 * sizeof(u_int32_t) + argp->fhsize;
517 	} else {
518 		argp->fhsize   = NFSX_V2FH;
519 		minlen = sizeof(u_int32_t) + argp->fhsize;
520 	}
521 
522 	if (m->m_len < minlen) {
523 		m = m_pullup(m, minlen);
524 		if (m == NULL)
525 			return(EBADRPC);
526 		rdata = mtod(m, struct rdata *);
527 	}
528 
529 	fh = (mntver == 3) ?
530 		rdata->fh.v3fh.fh : rdata->fh.v2fh;
531 	bcopy(fh, argp->fh, argp->fhsize);
532 
533 	goto out;
534 
535 bad:
536 	error = EBADRPC;
537 
538 out:
539 	m_freem(m);
540 	return error;
541 }
542