xref: /netbsd-src/sys/nfs/krpc_subr.c (revision 3b01aba77a7a698587faaae455bbfe740923c1f5)
1 /*	$NetBSD: krpc_subr.c,v 1.24 2001/06/12 15:17:28 wiz Exp $	*/
2 
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  * partially based on:
41  *      libnetboot/rpc.c
42  *               @(#) Header: rpc.c,v 1.12 93/09/28 08:31:56 leres Exp  (LBL)
43  */
44 
45 #include <sys/param.h>
46 #include <sys/systm.h>
47 #include <sys/conf.h>
48 #include <sys/ioctl.h>
49 #include <sys/proc.h>
50 #include <sys/mount.h>
51 #include <sys/mbuf.h>
52 #include <sys/reboot.h>
53 #include <sys/socket.h>
54 #include <sys/socketvar.h>
55 
56 #include <net/if.h>
57 #include <netinet/in.h>
58 
59 #include <nfs/rpcv2.h>
60 #include <nfs/krpc.h>
61 #include <nfs/xdr_subs.h>
62 #include <nfs/nfsproto.h> /* XXX NFSX_V3FHMAX for next */
63 #include <nfs/nfs.h>
64 #include <nfs/nfsmount.h>
65 #include <nfs/nfsdiskless.h> /* XXX decl nfs_boot_sendrecv */
66 
67 /*
68  * Kernel support for Sun RPC
69  *
70  * Used currently for bootstrapping in nfs diskless configurations.
71  */
72 
73 /*
74  * Generic RPC headers
75  */
76 
77 struct auth_info {
78 	u_int32_t 	authtype;	/* auth type */
79 	u_int32_t	authlen;	/* auth length */
80 };
81 
82 struct auth_unix {
83 	int32_t   ua_time;
84 	int32_t   ua_hostname;	/* null */
85 	int32_t   ua_uid;
86 	int32_t   ua_gid;
87 	int32_t   ua_gidlist;	/* null */
88 };
89 
90 struct rpc_call {
91 	u_int32_t	rp_xid;		/* request transaction id */
92 	int32_t 	rp_direction;	/* call direction (0) */
93 	u_int32_t	rp_rpcvers;	/* rpc version (2) */
94 	u_int32_t	rp_prog;	/* program */
95 	u_int32_t	rp_vers;	/* version */
96 	u_int32_t	rp_proc;	/* procedure */
97 	struct	auth_info rpc_auth;
98 	struct	auth_unix rpc_unix;
99 	struct	auth_info rpc_verf;
100 };
101 
102 struct rpc_reply {
103 	u_int32_t rp_xid;		/* request transaction id */
104 	int32_t  rp_direction;		/* call direction (1) */
105 	int32_t  rp_astatus;		/* accept status (0: accepted) */
106 	union {
107 		/* rejected */
108 		struct {
109 			u_int32_t rej_stat;
110 			u_int32_t rej_val1;
111 			u_int32_t rej_val2;
112 		} rpu_rej;
113 		/* accepted */
114 		struct {
115 			struct auth_info rok_auth;
116 			u_int32_t	rok_status;
117 		} rpu_rok;
118 	} rp_u;
119 };
120 #define rp_rstat  rp_u.rpu_rej.rej_stat
121 #define rp_auth   rp_u.rpu_rok.rok_auth
122 #define rp_status rp_u.rpu_rok.rok_status
123 
124 #define MIN_REPLY_HDR 16	/* xid, dir, astat, errno */
125 
126 static int krpccheck __P((struct mbuf*, void*));
127 
128 /*
129  * Call portmap to lookup a port number for a particular rpc program
130  * Returns non-zero error on failure.
131  */
132 int
133 krpc_portmap(sin,  prog, vers, proto, portp)
134 	struct sockaddr_in *sin;		/* server address */
135 	u_int prog, vers, proto;	/* host order */
136 	u_int16_t *portp;	/* network order */
137 {
138 	struct sdata {
139 		u_int32_t prog;		/* call program */
140 		u_int32_t vers;		/* call version */
141 		u_int32_t proto;	/* call protocol */
142 		u_int32_t port;		/* call port (unused) */
143 	} *sdata;
144 	struct rdata {
145 		u_int16_t pad;
146 		u_int16_t port;
147 	} *rdata;
148 	struct mbuf *m;
149 	int error;
150 
151 	/* The portmapper port is fixed. */
152 	if (prog == PMAPPROG) {
153 		*portp = htons(PMAPPORT);
154 		return 0;
155 	}
156 
157 	m = m_get(M_WAIT, MT_DATA);
158 	sdata = mtod(m, struct sdata *);
159 	m->m_len = sizeof(*sdata);
160 
161 	/* Do the RPC to get it. */
162 	sdata->prog = txdr_unsigned(prog);
163 	sdata->vers = txdr_unsigned(vers);
164 	sdata->proto = txdr_unsigned(proto);
165 	sdata->port = 0;
166 
167 	sin->sin_port = htons(PMAPPORT);
168 	error = krpc_call(sin, PMAPPROG, PMAPVERS,
169 					  PMAPPROC_GETPORT, &m, NULL);
170 	if (error)
171 		return error;
172 
173 	if (m->m_len < sizeof(*rdata)) {
174 		m = m_pullup(m, sizeof(*rdata));
175 		if (m == NULL)
176 			return ENOBUFS;
177 	}
178 	rdata = mtod(m, struct rdata *);
179 	*portp = rdata->port;
180 
181 	m_freem(m);
182 	return 0;
183 }
184 
185 static int krpccheck(m, context)
186 struct mbuf *m;
187 void *context;
188 {
189 	struct rpc_reply *reply;
190 
191 	/* Does the reply contain at least a header? */
192 	if (m->m_pkthdr.len < MIN_REPLY_HDR)
193 		return(-1);
194 	if (m->m_len < sizeof(struct rpc_reply)) {
195 		m = m_pullup(m, sizeof(struct rpc_reply));
196 		if (m == NULL)
197 			return(-1);
198 	}
199 	reply = mtod(m, struct rpc_reply *);
200 
201 	/* Is it the right reply? */
202 	if (reply->rp_direction != txdr_unsigned(RPC_REPLY))
203 		return(-1);
204 
205 	if (reply->rp_xid != txdr_unsigned(*(u_int32_t*)context))
206 		return(-1);
207 
208 	return(0);
209 }
210 
211 /*
212  * Do a remote procedure call (RPC) and wait for its reply.
213  * If from_p is non-null, then we are doing broadcast, and
214  * the address from whence the response came is saved there.
215  */
216 int
217 krpc_call(sa, prog, vers, func, data, from_p)
218 	struct sockaddr_in *sa;
219 	u_int prog, vers, func;
220 	struct mbuf **data;	/* input/output */
221 	struct mbuf **from_p;	/* output */
222 {
223 	struct socket *so;
224 	struct sockaddr_in *sin;
225 	struct mbuf *m, *nam, *mhead, *from;
226 	struct rpc_call *call;
227 	struct rpc_reply *reply;
228 	int error, len;
229 	static u_int32_t xid = ~0xFF;
230 	u_int16_t tport;
231 
232 	/*
233 	 * Validate address family.
234 	 * Sorry, this is INET specific...
235 	 */
236 	if (sa->sin_family != AF_INET)
237 		return (EAFNOSUPPORT);
238 
239 	/* Free at end if not null. */
240 	nam = mhead = NULL;
241 	from = NULL;
242 
243 	/*
244 	 * Create socket and set its receive timeout.
245 	 */
246 	if ((error = socreate(AF_INET, &so, SOCK_DGRAM, 0)))
247 		goto out;
248 
249 	if ((error = nfs_boot_setrecvtimo(so)))
250 		goto out;
251 
252 	/*
253 	 * Enable broadcast if necessary.
254 	 */
255 	if (from_p) {
256 		if ((error = nfs_boot_enbroadcast(so)))
257 			goto out;
258 	}
259 
260 	/*
261 	 * Bind the local endpoint to a reserved port,
262 	 * because some NFS servers refuse requests from
263 	 * non-reserved (non-privileged) ports.
264 	 */
265 	tport = IPPORT_RESERVED;
266 	do {
267 		tport--;
268 		error = nfs_boot_sobind_ipport(so, tport);
269 	} while (error == EADDRINUSE &&
270 			 tport > IPPORT_RESERVED / 2);
271 	if (error) {
272 		printf("bind failed\n");
273 		goto out;
274 	}
275 
276 	/*
277 	 * Setup socket address for the server.
278 	 */
279 	nam = m_get(M_WAIT, MT_SONAME);
280 	sin = mtod(nam, struct sockaddr_in *);
281 	memcpy((caddr_t)sin, (caddr_t)sa,
282 		  (nam->m_len = sa->sin_len));
283 
284 	/*
285 	 * Prepend RPC message header.
286 	 */
287 	mhead = m_gethdr(M_WAIT, MT_DATA);
288 	mhead->m_next = *data;
289 	call = mtod(mhead, struct rpc_call *);
290 	mhead->m_len = sizeof(*call);
291 	memset((caddr_t)call, 0, sizeof(*call));
292 	/* rpc_call part */
293 	xid++;
294 	call->rp_xid = txdr_unsigned(xid);
295 	/* call->rp_direction = 0; */
296 	call->rp_rpcvers = txdr_unsigned(2);
297 	call->rp_prog = txdr_unsigned(prog);
298 	call->rp_vers = txdr_unsigned(vers);
299 	call->rp_proc = txdr_unsigned(func);
300 	/* rpc_auth part (auth_unix as root) */
301 	call->rpc_auth.authtype = txdr_unsigned(RPCAUTH_UNIX);
302 	call->rpc_auth.authlen  = txdr_unsigned(sizeof(struct auth_unix));
303 	/* rpc_verf part (auth_null) */
304 	call->rpc_verf.authtype = 0;
305 	call->rpc_verf.authlen  = 0;
306 
307 	/*
308 	 * Setup packet header
309 	 */
310 	len = 0;
311 	m = mhead;
312 	while (m) {
313 		len += m->m_len;
314 		m = m->m_next;
315 	}
316 	mhead->m_pkthdr.len = len;
317 	mhead->m_pkthdr.rcvif = NULL;
318 
319 	error = nfs_boot_sendrecv(so, nam, 0, mhead, krpccheck, &m, &from, &xid);
320 	if (error)
321 		goto out;
322 
323 	/* m_pullup() was done in krpccheck() */
324 	reply = mtod(m, struct rpc_reply *);
325 
326 	/* Was RPC accepted? (authorization OK) */
327 	if (reply->rp_astatus != 0) {
328 		/* Note: This is NOT an error code! */
329 		error = fxdr_unsigned(u_int32_t, reply->rp_rstat);
330 		switch (error) {
331 		    case RPC_MISMATCH:
332 			/* .re_status = RPC_VERSMISMATCH; */
333 			error = ERPCMISMATCH;
334 			break;
335 		    case RPC_AUTHERR:
336 			/* .re_status = RPC_AUTHERROR; */
337 			error = EAUTH;
338 			break;
339 		    default:
340 			/* unexpected */
341 			error = EBADRPC;
342 			break;
343 		}
344 		goto out;
345 	}
346 
347 	/* Did the call succeed? */
348 	if (reply->rp_status != 0) {
349 		/* Note: This is NOT an error code! */
350 		error = fxdr_unsigned(u_int32_t, reply->rp_status);
351 		switch (error) {
352 		    case RPC_PROGUNAVAIL:
353 			error = EPROGUNAVAIL;
354 			break;
355 		    case RPC_PROGMISMATCH:
356 			error = EPROGMISMATCH;
357 			break;
358 		    case RPC_PROCUNAVAIL:
359 			error = EPROCUNAVAIL;
360 			break;
361 		    case RPC_GARBAGE:
362 		    default:
363 			error = EBADRPC;
364 		}
365 		goto out;
366 	}
367 
368 	/*
369 	 * OK, we have received a good reply!
370 	 * Get its length, then strip it off.
371 	 */
372 	len = sizeof(*reply);
373 	if (reply->rp_auth.authtype != 0) {
374 		len += fxdr_unsigned(u_int32_t, reply->rp_auth.authlen);
375 		len = (len + 3) & ~3; /* XXX? */
376 	}
377 	m_adj(m, len);
378 
379 	/* result */
380 	*data = m;
381 	if (from_p) {
382 		*from_p = from;
383 		from = NULL;
384 	}
385 
386  out:
387 	if (nam) m_freem(nam);
388 	if (mhead) m_freem(mhead);
389 	if (from) m_freem(from);
390 	soclose(so);
391 	return error;
392 }
393 
394 /*
395  * eXternal Data Representation routines.
396  * (but with non-standard args...)
397  */
398 
399 /*
400  * String representation for RPC.
401  */
402 struct xdr_string {
403 	u_int32_t len;		/* length without null or padding */
404 	char data[4];	/* data (longer, of course) */
405     /* data is padded to a long-word boundary */
406 };
407 
408 struct mbuf *
409 xdr_string_encode(str, len)
410 	char *str;
411 	int len;
412 {
413 	struct mbuf *m;
414 	struct xdr_string *xs;
415 	int dlen;	/* padded string length */
416 	int mlen;	/* message length */
417 
418 	dlen = (len + 3) & ~3;
419 	mlen = dlen + 4;
420 
421 	if (mlen > MCLBYTES)		/* If too big, we just can't do it. */
422 		return (NULL);
423 
424 	m = m_get(M_WAIT, MT_DATA);
425 	if (mlen > MLEN) {
426 		MCLGET(m, M_WAIT);
427 		if ((m->m_flags & M_EXT) == 0) {
428 			(void) m_free(m);	/* There can be only one. */
429 			return (NULL);
430 		}
431 	}
432 	xs = mtod(m, struct xdr_string *);
433 	m->m_len = mlen;
434 	xs->len = txdr_unsigned(len);
435 	memcpy(xs->data, str, len);
436 	return (m);
437 }
438 
439 struct mbuf *
440 xdr_string_decode(m, str, len_p)
441 	struct mbuf *m;
442 	char *str;
443 	int *len_p;		/* bufsize - 1 */
444 {
445 	struct xdr_string *xs;
446 	int mlen;	/* message length */
447 	int slen;	/* string length */
448 
449 	if (m->m_len < 4) {
450 		m = m_pullup(m, 4);
451 		if (m == NULL)
452 			return (NULL);
453 	}
454 	xs = mtod(m, struct xdr_string *);
455 	slen = fxdr_unsigned(u_int32_t, xs->len);
456 	mlen = 4 + ((slen + 3) & ~3);
457 
458 	if (slen > *len_p)
459 		slen = *len_p;
460 	m_copydata(m, 4, slen, str);
461 	m_adj(m, mlen);
462 
463 	str[slen] = '\0';
464 	*len_p = slen;
465 
466 	return (m);
467 }
468 
469 
470 /*
471  * Inet address in RPC messages
472  * (Note, really four ints, NOT chars.  Blech.)
473  */
474 struct xdr_inaddr {
475 	u_int32_t atype;
476 	u_int32_t addr[4];
477 };
478 
479 struct mbuf *
480 xdr_inaddr_encode(ia)
481 	struct in_addr *ia;		/* already in network order */
482 {
483 	struct mbuf *m;
484 	struct xdr_inaddr *xi;
485 	u_int8_t *cp;
486 	u_int32_t *ip;
487 
488 	m = m_get(M_WAIT, MT_DATA);
489 	xi = mtod(m, struct xdr_inaddr *);
490 	m->m_len = sizeof(*xi);
491 	xi->atype = txdr_unsigned(1);
492 	ip = xi->addr;
493 	cp = (u_int8_t *)&ia->s_addr;
494 	*ip++ = txdr_unsigned(*cp++);
495 	*ip++ = txdr_unsigned(*cp++);
496 	*ip++ = txdr_unsigned(*cp++);
497 	*ip++ = txdr_unsigned(*cp++);
498 
499 	return (m);
500 }
501 
502 struct mbuf *
503 xdr_inaddr_decode(m, ia)
504 	struct mbuf *m;
505 	struct in_addr *ia;		/* already in network order */
506 {
507 	struct xdr_inaddr *xi;
508 	u_int8_t *cp;
509 	u_int32_t *ip;
510 
511 	if (m->m_len < sizeof(*xi)) {
512 		m = m_pullup(m, sizeof(*xi));
513 		if (m == NULL)
514 			return (NULL);
515 	}
516 	xi = mtod(m, struct xdr_inaddr *);
517 	if (xi->atype != txdr_unsigned(1)) {
518 		ia->s_addr = INADDR_ANY;
519 		goto out;
520 	}
521 	ip = xi->addr;
522 	cp = (u_int8_t *)&ia->s_addr;
523 	*cp++ = fxdr_unsigned(u_int8_t, *ip++);
524 	*cp++ = fxdr_unsigned(u_int8_t, *ip++);
525 	*cp++ = fxdr_unsigned(u_int8_t, *ip++);
526 	*cp++ = fxdr_unsigned(u_int8_t, *ip++);
527 
528 out:
529 	m_adj(m, sizeof(*xi));
530 	return (m);
531 }
532