1 /*	$NetBSD: nfs_diskless.c,v 1.1.1.1 2013/09/30 07:19:32 dholland Exp $	*/
2 /*-
3  * Copyright (c) 1990 The Regents of the University of California.
4  * All rights reserved.
5  *
6  * This code is derived from software contributed to Berkeley by
7  * William Jolitz.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  *	from: @(#)autoconf.c	7.1 (Berkeley) 5/9/91
34  */
35 
36 #include <sys/cdefs.h>
37 /* __FBSDID("FreeBSD: head/sys/nfs/nfs_diskless.c 221436 2011-05-04 13:27:45Z ru "); */
38 __RCSID("$NetBSD: nfs_diskless.c,v 1.1.1.1 2013/09/30 07:19:32 dholland Exp $");
39 
40 #include "opt_bootp.h"
41 
42 #include <sys/param.h>
43 #include <sys/systm.h>
44 #include <sys/jail.h>
45 #include <sys/kernel.h>
46 #include <sys/malloc.h>
47 #include <sys/mount.h>
48 #include <sys/socket.h>
49 
50 #include <net/if.h>
51 #include <net/if_dl.h>
52 #include <net/if_types.h>
53 #include <net/if_var.h>
54 #include <net/ethernet.h>
55 #include <net/vnet.h>
56 
57 #include <netinet/in.h>
58 #include <nfs/nfsproto.h>
59 #include <nfsclient/nfs.h>
60 #include <nfs/nfsdiskless.h>
61 
62 static int inaddr_to_sockaddr(char *ev, struct sockaddr_in *sa);
63 static int hwaddr_to_sockaddr(char *ev, struct sockaddr_dl *sa);
64 static int decode_nfshandle(char *ev, u_char *fh, int maxfh);
65 
66 /*
67  * This structure must be filled in by a primary bootstrap or bootstrap
68  * server for a diskless/dataless machine. It is initialized below just
69  * to ensure that it is allocated to initialized data (.data not .bss).
70  */
71 struct nfs_diskless	nfs_diskless = { { { 0 } } };
72 struct nfsv3_diskless	nfsv3_diskless = { { { 0 } } };
73 int			nfs_diskless_valid = 0;
74 
75 /*
76  * Validate/sanity check a rsize/wsize parameter.
77  */
78 static int
checkrwsize(unsigned long v,const char * name)79 checkrwsize(unsigned long v, const char *name)
80 {
81 	/*
82 	 * 32K is used as an upper bound because most servers
83 	 * limit block size to satisfy IPv4's limit of
84 	 * 64K/reassembled packet.  The lower bound is pretty
85 	 * much arbitrary.
86 	 */
87 	if (!(4 <= v && v <= 32*1024)) {
88 		printf("nfs_parse_options: invalid %s %lu ignored\n", name, v);
89 		return 0;
90 	} else
91 		return 1;
92 }
93 
94 /*
95  * Parse mount options and apply them to the supplied
96  * nfs_diskless state.  Used also by bootp/dhcp support.
97  */
98 void
nfs_parse_options(const char * envopts,struct nfs_args * nd)99 nfs_parse_options(const char *envopts, struct nfs_args *nd)
100 {
101 	char *opts, *o, *otmp;
102 	unsigned long v;
103 
104 	opts = strdup(envopts, M_TEMP);
105 	otmp = opts;
106 	while ((o = strsep(&otmp, ":;, ")) != NULL) {
107 		if (*o == '\0')
108 			; /* Skip empty options. */
109 		else if (strcmp(o, "soft") == 0)
110 			nd->flags |= NFSMNT_SOFT;
111 		else if (strcmp(o, "intr") == 0)
112 			nd->flags |= NFSMNT_INT;
113 		else if (strcmp(o, "conn") == 0)
114 			nd->flags |= NFSMNT_NOCONN;
115 		else if (strcmp(o, "nolockd") == 0)
116 			nd->flags |= NFSMNT_NOLOCKD;
117 		else if (strcmp(o, "nocto") == 0)
118 			nd->flags |= NFSMNT_NOCTO;
119 		else if (strcmp(o, "nfsv2") == 0)
120 			nd->flags &= ~(NFSMNT_NFSV3 | NFSMNT_NFSV4);
121 		else if (strcmp(o, "nfsv3") == 0) {
122 			nd->flags &= ~NFSMNT_NFSV4;
123 			nd->flags |= NFSMNT_NFSV3;
124 		} else if (strcmp(o, "tcp") == 0)
125 			nd->sotype = SOCK_STREAM;
126 		else if (strcmp(o, "udp") == 0)
127 			nd->sotype = SOCK_DGRAM;
128 		else if (strncmp(o, "rsize=", 6) == 0) {
129 			v = strtoul(o+6, NULL, 10);
130 			if (checkrwsize(v, "rsize")) {
131 				nd->rsize = (int) v;
132 				nd->flags |= NFSMNT_RSIZE;
133 			}
134 		} else if (strncmp(o, "wsize=", 6) == 0) {
135 			v = strtoul(o+6, NULL, 10);
136 			if (checkrwsize(v, "wsize")) {
137 				nd->wsize = (int) v;
138 				nd->flags |= NFSMNT_WSIZE;
139 			}
140 		} else
141 			printf("%s: skipping unknown option \"%s\"\n",
142 			    __func__, o);
143 	}
144 	free(opts, M_TEMP);
145 }
146 
147 /*
148  * Populate the essential fields in the nfsv3_diskless structure.
149  *
150  * The loader is expected to export the following environment variables:
151  *
152  * boot.netif.name		name of boot interface
153  * boot.netif.ip		IP address on boot interface
154  * boot.netif.netmask		netmask on boot interface
155  * boot.netif.gateway		default gateway (optional)
156  * boot.netif.hwaddr		hardware address of boot interface
157  * boot.nfsroot.server		IP address of root filesystem server
158  * boot.nfsroot.path		path of the root filesystem on server
159  * boot.nfsroot.nfshandle	NFS handle for root filesystem on server
160  * boot.nfsroot.nfshandlelen	and length of this handle (for NFSv3 only)
161  * boot.nfsroot.options		NFS options for the root filesystem
162  */
163 void
nfs_setup_diskless(void)164 nfs_setup_diskless(void)
165 {
166 	struct nfs_diskless *nd = &nfs_diskless;
167 	struct nfsv3_diskless *nd3 = &nfsv3_diskless;
168 	struct ifnet *ifp;
169 	struct ifaddr *ifa;
170 	struct sockaddr_dl *sdl, ourdl;
171 	struct sockaddr_in myaddr, netmask;
172 	char *cp;
173 	int cnt, fhlen, is_nfsv3;
174 	uint32_t len;
175 
176 	if (nfs_diskless_valid != 0)
177 		return;
178 
179 	/* get handle size. If this succeeds, it's an NFSv3 setup. */
180 	if ((cp = getenv("boot.nfsroot.nfshandlelen")) != NULL) {
181 		cnt = sscanf(cp, "%d", &len);
182 		freeenv(cp);
183 		if (cnt != 1 || len == 0 || len > NFSX_V3FHMAX) {
184 			printf("nfs_diskless: bad NFS handle len\n");
185 			return;
186 		}
187 		nd3->root_fhsize = len;
188 		is_nfsv3 = 1;
189 	} else
190 		is_nfsv3 = 0;
191 	/* set up interface */
192 	if (inaddr_to_sockaddr("boot.netif.ip", &myaddr))
193 		return;
194 	if (inaddr_to_sockaddr("boot.netif.netmask", &netmask)) {
195 		printf("nfs_diskless: no netmask\n");
196 		return;
197 	}
198 	if (is_nfsv3 != 0) {
199 		bcopy(&myaddr, &nd3->myif.ifra_addr, sizeof(myaddr));
200 		bcopy(&myaddr, &nd3->myif.ifra_broadaddr, sizeof(myaddr));
201 		((struct sockaddr_in *)
202 		   &nd3->myif.ifra_broadaddr)->sin_addr.s_addr =
203 		    myaddr.sin_addr.s_addr | ~ netmask.sin_addr.s_addr;
204 		bcopy(&netmask, &nd3->myif.ifra_mask, sizeof(netmask));
205 	} else {
206 		bcopy(&myaddr, &nd->myif.ifra_addr, sizeof(myaddr));
207 		bcopy(&myaddr, &nd->myif.ifra_broadaddr, sizeof(myaddr));
208 		((struct sockaddr_in *)
209 		   &nd->myif.ifra_broadaddr)->sin_addr.s_addr =
210 		    myaddr.sin_addr.s_addr | ~ netmask.sin_addr.s_addr;
211 		bcopy(&netmask, &nd->myif.ifra_mask, sizeof(netmask));
212 	}
213 
214 	if (hwaddr_to_sockaddr("boot.netif.hwaddr", &ourdl)) {
215 		printf("nfs_diskless: no hardware address\n");
216 		return;
217 	}
218 	ifa = NULL;
219 	CURVNET_SET(TD_TO_VNET(curthread));
220 	IFNET_RLOCK();
221 	TAILQ_FOREACH(ifp, &V_ifnet, if_link) {
222 		TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
223 			if (ifa->ifa_addr->sa_family == AF_LINK) {
224 				sdl = (struct sockaddr_dl *)ifa->ifa_addr;
225 				if ((sdl->sdl_type == ourdl.sdl_type) &&
226 				    (sdl->sdl_alen == ourdl.sdl_alen) &&
227 				    !bcmp(LLADDR(sdl),
228 					  LLADDR(&ourdl),
229 					  sdl->sdl_alen)) {
230 				    IFNET_RUNLOCK();
231 				    CURVNET_RESTORE();
232 				    goto match_done;
233 				}
234 			}
235 		}
236 	}
237 	IFNET_RUNLOCK();
238 	CURVNET_RESTORE();
239 	printf("nfs_diskless: no interface\n");
240 	return;	/* no matching interface */
241 match_done:
242 	setenv("boot.netif.name", ifp->if_xname);
243 	if (is_nfsv3 != 0) {
244 		strlcpy(nd3->myif.ifra_name, ifp->if_xname,
245 		    sizeof(nd3->myif.ifra_name));
246 
247 		/* set up gateway */
248 		inaddr_to_sockaddr("boot.netif.gateway", &nd3->mygateway);
249 
250 		/* set up root mount */
251 		nd3->root_args.rsize = 32768;		/* XXX tunable? */
252 		nd3->root_args.wsize = 32768;
253 		nd3->root_args.sotype = SOCK_STREAM;
254 		nd3->root_args.flags = (NFSMNT_NFSV3 | NFSMNT_WSIZE |
255 		    NFSMNT_RSIZE | NFSMNT_RESVPORT);
256 		if (inaddr_to_sockaddr("boot.nfsroot.server",
257 		    &nd3->root_saddr)) {
258 			printf("nfs_diskless: no server\n");
259 			return;
260 		}
261 		nd3->root_saddr.sin_port = htons(NFS_PORT);
262 		fhlen = decode_nfshandle("boot.nfsroot.nfshandle",
263 		    &nd3->root_fh[0], NFSX_V3FHMAX);
264 		if (fhlen == 0) {
265 			printf("nfs_diskless: no NFS handle\n");
266 			return;
267 		}
268 		if (fhlen != nd3->root_fhsize) {
269 			printf("nfs_diskless: bad NFS handle len=%d\n", fhlen);
270 			return;
271 		}
272 		if ((cp = getenv("boot.nfsroot.path")) != NULL) {
273 			strncpy(nd3->root_hostnam, cp, MNAMELEN - 1);
274 			freeenv(cp);
275 		}
276 		if ((cp = getenv("boot.nfsroot.options")) != NULL) {
277 			nfs_parse_options(cp, &nd3->root_args);
278 			freeenv(cp);
279 		}
280 
281 		nfs_diskless_valid = 3;
282 	} else {
283 		strlcpy(nd->myif.ifra_name, ifp->if_xname,
284 		    sizeof(nd->myif.ifra_name));
285 
286 		/* set up gateway */
287 		inaddr_to_sockaddr("boot.netif.gateway", &nd->mygateway);
288 
289 		/* set up root mount */
290 		nd->root_args.rsize = 8192;		/* XXX tunable? */
291 		nd->root_args.wsize = 8192;
292 		nd->root_args.sotype = SOCK_STREAM;
293 		nd->root_args.flags = (NFSMNT_WSIZE |
294 		    NFSMNT_RSIZE | NFSMNT_RESVPORT);
295 		if (inaddr_to_sockaddr("boot.nfsroot.server",
296 		    &nd->root_saddr)) {
297 			printf("nfs_diskless: no server\n");
298 			return;
299 		}
300 		nd->root_saddr.sin_port = htons(NFS_PORT);
301 		if (decode_nfshandle("boot.nfsroot.nfshandle",
302 		    &nd->root_fh[0], NFSX_V2FH) == 0) {
303 			printf("nfs_diskless: no NFS handle\n");
304 			return;
305 		}
306 		if ((cp = getenv("boot.nfsroot.path")) != NULL) {
307 			strncpy(nd->root_hostnam, cp, MNAMELEN - 1);
308 			freeenv(cp);
309 		}
310 		if ((cp = getenv("boot.nfsroot.options")) != NULL) {
311 			struct nfs_args args;
312 
313 			/*
314 			 * XXX yech, convert between old and current
315 			 * arg format
316 			 */
317 			args.flags = nd->root_args.flags;
318 			args.sotype = nd->root_args.sotype;
319 			args.rsize = nd->root_args.rsize;
320 			args.wsize = nd->root_args.wsize;
321 			nfs_parse_options(cp, &args);
322 			nd->root_args.flags = args.flags;
323 			nd->root_args.sotype = args.sotype;
324 			nd->root_args.rsize = args.rsize;
325 			nd->root_args.wsize = args.wsize;
326 			freeenv(cp);
327 		}
328 
329 		nfs_diskless_valid = 1;
330 	}
331 }
332 
333 static int
inaddr_to_sockaddr(char * ev,struct sockaddr_in * sa)334 inaddr_to_sockaddr(char *ev, struct sockaddr_in *sa)
335 {
336 	u_int32_t a[4];
337 	char *cp;
338 	int count;
339 
340 	bzero(sa, sizeof(*sa));
341 	sa->sin_len = sizeof(*sa);
342 	sa->sin_family = AF_INET;
343 
344 	if ((cp = getenv(ev)) == NULL)
345 		return (1);
346 	count = sscanf(cp, "%d.%d.%d.%d", &a[0], &a[1], &a[2], &a[3]);
347 	freeenv(cp);
348 	if (count != 4)
349 		return (1);
350 	sa->sin_addr.s_addr =
351 	    htonl((a[0] << 24) | (a[1] << 16) | (a[2] << 8) | a[3]);
352 	return (0);
353 }
354 
355 static int
hwaddr_to_sockaddr(char * ev,struct sockaddr_dl * sa)356 hwaddr_to_sockaddr(char *ev, struct sockaddr_dl *sa)
357 {
358 	char *cp;
359 	u_int32_t a[6];
360 	int count;
361 
362 	bzero(sa, sizeof(*sa));
363 	sa->sdl_len = sizeof(*sa);
364 	sa->sdl_family = AF_LINK;
365 	sa->sdl_type = IFT_ETHER;
366 	sa->sdl_alen = ETHER_ADDR_LEN;
367 	if ((cp = getenv(ev)) == NULL)
368 		return (1);
369 	count = sscanf(cp, "%x:%x:%x:%x:%x:%x",
370 	    &a[0], &a[1], &a[2], &a[3], &a[4], &a[5]);
371 	freeenv(cp);
372 	if (count != 6)
373 		return (1);
374 	sa->sdl_data[0] = a[0];
375 	sa->sdl_data[1] = a[1];
376 	sa->sdl_data[2] = a[2];
377 	sa->sdl_data[3] = a[3];
378 	sa->sdl_data[4] = a[4];
379 	sa->sdl_data[5] = a[5];
380 	return (0);
381 }
382 
383 static int
decode_nfshandle(char * ev,u_char * fh,int maxfh)384 decode_nfshandle(char *ev, u_char *fh, int maxfh)
385 {
386 	u_char *cp, *ep;
387 	int len, val;
388 
389 	ep = cp = getenv(ev);
390 	if (cp == NULL)
391 		return (0);
392 	if ((strlen(cp) < 2) || (*cp != 'X')) {
393 		freeenv(ep);
394 		return (0);
395 	}
396 	len = 0;
397 	cp++;
398 	for (;;) {
399 		if (*cp == 'X') {
400 			freeenv(ep);
401 			return (len);
402 		}
403 		if ((sscanf(cp, "%2x", &val) != 1) || (val > 0xff)) {
404 			freeenv(ep);
405 			return (0);
406 		}
407 		*(fh++) = val;
408 		len++;
409 		cp += 2;
410 		if (len > maxfh) {
411 		    freeenv(ep);
412 		    return (0);
413 		}
414 	}
415 }
416 
417 #if !defined(BOOTP_NFSROOT)
418 static void
nfs_rootconf(void)419 nfs_rootconf(void)
420 {
421 
422 	nfs_setup_diskless();
423 	if (nfs_diskless_valid)
424 		rootdevnames[0] = "nfs:";
425 }
426 
427 SYSINIT(cpu_rootconf, SI_SUB_ROOT_CONF, SI_ORDER_FIRST, nfs_rootconf, NULL);
428 #endif
429 
430