1 /* $OpenBSD: krpc_subr.c,v 1.14 2007/02/27 19:09:56 deraadt Exp $ */
2 /* $NetBSD: krpc_subr.c,v 1.12.4.1 1996/06/07 00:52:26 cgd Exp $ */
3
4 /*
5 * Copyright (c) 1995 Gordon Ross, Adam Glass
6 * Copyright (c) 1992 Regents of the University of California.
7 * All rights reserved.
8 *
9 * This software was developed by the Computer Systems Engineering group
10 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
11 * contributed to Berkeley.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 * 1. Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution.
21 * 3. All advertising materials mentioning features or use of this software
22 * must display the following acknowledgement:
23 * This product includes software developed by the University of
24 * California, Lawrence Berkeley Laboratory and its contributors.
25 * 4. Neither the name of the University nor the names of its contributors
26 * may be used to endorse or promote products derived from this software
27 * without specific prior written permission.
28 *
29 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
30 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
31 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
32 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
33 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
34 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
35 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
36 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
37 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
38 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
39 * SUCH DAMAGE.
40 *
41 * partially based on:
42 * libnetboot/rpc.c
43 * @(#) Header: rpc.c,v 1.12 93/09/28 08:31:56 leres Exp (LBL)
44 */
45
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/conf.h>
49 #include <sys/ioctl.h>
50 #include <sys/proc.h>
51 #include <sys/mount.h>
52 #include <sys/mbuf.h>
53 #include <sys/reboot.h>
54 #include <sys/socket.h>
55 #include <sys/socketvar.h>
56
57 #include <net/if.h>
58 #include <netinet/in.h>
59
60 #include <nfs/rpcv2.h>
61 #include <nfs/krpc.h>
62 #include <nfs/xdr_subs.h>
63 #include <dev/rndvar.h>
64
65 /*
66 * Kernel support for Sun RPC
67 *
68 * Used currently for bootstrapping in nfs diskless configurations.
69 */
70
71 /*
72 * Generic RPC headers
73 */
74
75 struct auth_info {
76 u_int32_t authtype; /* auth type */
77 u_int32_t authlen; /* auth length */
78 };
79
80 struct auth_unix {
81 int32_t ua_time;
82 int32_t ua_hostname; /* null */
83 int32_t ua_uid;
84 int32_t ua_gid;
85 int32_t ua_gidlist; /* null */
86 };
87
88 struct rpc_call {
89 u_int32_t rp_xid; /* request transaction id */
90 int32_t rp_direction; /* call direction (0) */
91 u_int32_t rp_rpcvers; /* rpc version (2) */
92 u_int32_t rp_prog; /* program */
93 u_int32_t rp_vers; /* version */
94 u_int32_t rp_proc; /* procedure */
95 struct auth_info rpc_auth;
96 struct auth_unix rpc_unix;
97 struct auth_info rpc_verf;
98 };
99
100 struct rpc_reply {
101 u_int32_t rp_xid; /* request transaction id */
102 int32_t rp_direction; /* call direction (1) */
103 int32_t rp_astatus; /* accept status (0: accepted) */
104 union {
105 u_int32_t rpu_errno;
106 struct {
107 struct auth_info rok_auth;
108 u_int32_t rok_status;
109 } rpu_rok;
110 } rp_u;
111 };
112 #define rp_errno rp_u.rpu_errno
113 #define rp_auth rp_u.rpu_rok.rok_auth
114 #define rp_status rp_u.rpu_rok.rok_status
115
116 #define MIN_REPLY_HDR 16 /* xid, dir, astat, errno */
117
118 /*
119 * What is the longest we will wait before re-sending a request?
120 * Note this is also the frequency of "RPC timeout" messages.
121 * The re-send loop count sup linearly to this maximum, so the
122 * first complaint will happen after (1+2+3+4+5)=15 seconds.
123 */
124 #define MAX_RESEND_DELAY 5 /* seconds */
125
126 /*
127 * Call portmap to lookup a port number for a particular rpc program
128 * Returns non-zero error on failure.
129 */
130 int
131 krpc_portmap(sin, prog, vers, portp)
132 struct sockaddr_in *sin; /* server address */
133 u_int prog, vers; /* host order */
134 u_int16_t *portp; /* network order */
135 {
136 struct sdata {
137 u_int32_t prog; /* call program */
138 u_int32_t vers; /* call version */
139 u_int32_t proto; /* call protocol */
140 u_int32_t port; /* call port (unused) */
141 } *sdata;
142 struct rdata {
143 u_int16_t pad;
144 u_int16_t port;
145 } *rdata;
146 struct mbuf *m;
147 int error;
148
149 /* The portmapper port is fixed. */
150 if (prog == PMAPPROG) {
151 *portp = htons(PMAPPORT);
152 return 0;
153 }
154
155 m = m_get(M_WAIT, MT_DATA);
156 sdata = mtod(m, struct sdata *);
157 m->m_len = sizeof(*sdata);
158
159 /* Do the RPC to get it. */
160 sdata->prog = txdr_unsigned(prog);
161 sdata->vers = txdr_unsigned(vers);
162 sdata->proto = txdr_unsigned(IPPROTO_UDP);
163 sdata->port = 0;
164
165 sin->sin_port = htons(PMAPPORT);
166 error = krpc_call(sin, PMAPPROG, PMAPVERS,
167 PMAPPROC_GETPORT, &m, NULL, -1);
168 if (error)
169 return error;
170
171 if (m->m_len < sizeof(*rdata)) {
172 m = m_pullup(m, sizeof(*rdata));
173 if (m == NULL)
174 return ENOBUFS;
175 }
176 rdata = mtod(m, struct rdata *);
177 *portp = rdata->port;
178
179 m_freem(m);
180 return 0;
181 }
182
183 /*
184 * Do a remote procedure call (RPC) and wait for its reply.
185 * If from_p is non-null, then we are doing broadcast, and
186 * the address from whence the response came is saved there.
187 */
188 int
189 krpc_call(sa, prog, vers, func, data, from_p, retries)
190 struct sockaddr_in *sa;
191 u_int prog, vers, func;
192 struct mbuf **data; /* input/output */
193 struct mbuf **from_p; /* output */
194 int retries;
195 {
196 struct socket *so;
197 struct sockaddr_in *sin;
198 struct mbuf *m, *nam, *mhead, *from, *mopt;
199 struct rpc_call *call;
200 struct rpc_reply *reply;
201 struct uio auio;
202 int error, rcvflg, timo, secs, len;
203 static u_int32_t xid = 0;
204 u_int32_t newxid;
205 int *ip;
206 struct timeval *tv;
207
208 /*
209 * Validate address family.
210 * Sorry, this is INET specific...
211 */
212 if (sa->sin_family != AF_INET)
213 return (EAFNOSUPPORT);
214
215 /* Free at end if not null. */
216 nam = mhead = NULL;
217 from = NULL;
218
219 /*
220 * Create socket and set its receive timeout.
221 */
222 if ((error = socreate(AF_INET, &so, SOCK_DGRAM, 0)))
223 goto out;
224
225 m = m_get(M_WAIT, MT_SOOPTS);
226 tv = mtod(m, struct timeval *);
227 m->m_len = sizeof(*tv);
228 tv->tv_sec = 1;
229 tv->tv_usec = 0;
230 if ((error = sosetopt(so, SOL_SOCKET, SO_RCVTIMEO, m)))
231 goto out;
232
233 /*
234 * Enable broadcast if necessary.
235 */
236 if (from_p) {
237 int32_t *on;
238 m = m_get(M_WAIT, MT_SOOPTS);
239 on = mtod(m, int32_t *);
240 m->m_len = sizeof(*on);
241 *on = 1;
242 if ((error = sosetopt(so, SOL_SOCKET, SO_BROADCAST, m)))
243 goto out;
244 }
245
246 /*
247 * Bind the local endpoint to a reserved port,
248 * because some NFS servers refuse requests from
249 * non-reserved (non-privileged) ports.
250 */
251 m = m_getclr(M_WAIT, MT_SONAME);
252 sin = mtod(m, struct sockaddr_in *);
253 sin->sin_len = m->m_len = sizeof(*sin);
254 sin->sin_family = AF_INET;
255 sin->sin_addr.s_addr = INADDR_ANY;
256
257 MGET(mopt, M_WAIT, MT_SOOPTS);
258 mopt->m_len = sizeof(int);
259 ip = mtod(mopt, int *);
260 *ip = IP_PORTRANGE_LOW;
261 error = sosetopt(so, IPPROTO_IP, IP_PORTRANGE, mopt);
262 if (error)
263 goto out;
264
265 MGET(m, M_WAIT, MT_SONAME);
266 sin = mtod(m, struct sockaddr_in *);
267 sin->sin_len = m->m_len = sizeof (struct sockaddr_in);
268 sin->sin_family = AF_INET;
269 sin->sin_addr.s_addr = INADDR_ANY;
270 sin->sin_port = htons(0);
271 error = sobind(so, m);
272 m_freem(m);
273 if (error) {
274 printf("bind failed\n");
275 goto out;
276 }
277
278 MGET(mopt, M_WAIT, MT_SOOPTS);
279 mopt->m_len = sizeof(int);
280 ip = mtod(mopt, int *);
281 *ip = IP_PORTRANGE_DEFAULT;
282 error = sosetopt(so, IPPROTO_IP, IP_PORTRANGE, mopt);
283 if (error)
284 goto out;
285
286 /*
287 * Setup socket address for the server.
288 */
289 nam = m_get(M_WAIT, MT_SONAME);
290 sin = mtod(nam, struct sockaddr_in *);
291 bcopy((caddr_t)sa, (caddr_t)sin, (nam->m_len = sa->sin_len));
292
293 /*
294 * Prepend RPC message header.
295 */
296 mhead = m_gethdr(M_WAIT, MT_DATA);
297 mhead->m_next = *data;
298 call = mtod(mhead, struct rpc_call *);
299 mhead->m_len = sizeof(*call);
300 bzero((caddr_t)call, sizeof(*call));
301 /* rpc_call part */
302 while ((newxid = arc4random()) == xid);
303 xid = newxid;
304 call->rp_xid = txdr_unsigned(xid);
305 /* call->rp_direction = 0; */
306 call->rp_rpcvers = txdr_unsigned(2);
307 call->rp_prog = txdr_unsigned(prog);
308 call->rp_vers = txdr_unsigned(vers);
309 call->rp_proc = txdr_unsigned(func);
310 /* rpc_auth part (auth_unix as root) */
311 call->rpc_auth.authtype = txdr_unsigned(RPCAUTH_UNIX);
312 call->rpc_auth.authlen = txdr_unsigned(sizeof(struct auth_unix));
313 /* rpc_verf part (auth_null) */
314 call->rpc_verf.authtype = 0;
315 call->rpc_verf.authlen = 0;
316
317 /*
318 * Setup packet header
319 */
320 len = 0;
321 m = mhead;
322 while (m) {
323 len += m->m_len;
324 m = m->m_next;
325 }
326 mhead->m_pkthdr.len = len;
327 mhead->m_pkthdr.rcvif = NULL;
328
329 /*
330 * Send it, repeatedly, until a reply is received,
331 * but delay each re-send by an increasing amount.
332 * If the delay hits the maximum, start complaining.
333 */
334 for (timo = 0; retries; retries--) {
335 /* Send RPC request (or re-send). */
336 m = m_copym(mhead, 0, M_COPYALL, M_WAIT);
337 if (m == NULL) {
338 error = ENOBUFS;
339 goto out;
340 }
341 error = sosend(so, nam, NULL, m, NULL, 0);
342 if (error) {
343 printf("krpc_call: sosend: %d\n", error);
344 goto out;
345 }
346 m = NULL;
347
348 /* Determine new timeout. */
349 if (timo < MAX_RESEND_DELAY)
350 timo++;
351 else
352 printf("RPC timeout for server %s (0x%x) prog %u\n",
353 inet_ntoa(sin->sin_addr),
354 ntohl(sin->sin_addr.s_addr), prog);
355
356 /*
357 * Wait for up to timo seconds for a reply.
358 * The socket receive timeout was set to 1 second.
359 */
360 secs = timo;
361 while (secs > 0) {
362 if (from) {
363 m_freem(from);
364 from = NULL;
365 }
366 if (m) {
367 m_freem(m);
368 m = NULL;
369 }
370 auio.uio_resid = len = 1<<16;
371 auio.uio_procp = NULL;
372 rcvflg = 0;
373 error = soreceive(so, &from, &auio, &m, NULL, &rcvflg);
374 if (error == EWOULDBLOCK) {
375 secs--;
376 continue;
377 }
378 if (error)
379 goto out;
380 len -= auio.uio_resid;
381
382 /* Does the reply contain at least a header? */
383 if (len < MIN_REPLY_HDR)
384 continue;
385 if (m->m_len < MIN_REPLY_HDR)
386 continue;
387 reply = mtod(m, struct rpc_reply *);
388
389 /* Is it the right reply? */
390 if (reply->rp_direction != txdr_unsigned(RPC_REPLY))
391 continue;
392
393 if (reply->rp_xid != txdr_unsigned(xid))
394 continue;
395
396 /* Was RPC accepted? (authorization OK) */
397 if (reply->rp_astatus != 0) {
398 error = fxdr_unsigned(u_int32_t, reply->rp_errno);
399 printf("rpc denied, error=%d\n", error);
400 continue;
401 }
402
403 /* Did the call succeed? */
404 if (reply->rp_status != 0) {
405 error = fxdr_unsigned(u_int32_t, reply->rp_status);
406 printf("rpc denied, status=%d\n", error);
407 continue;
408 }
409
410 goto gotreply; /* break two levels */
411
412 } /* while secs */
413 } /* forever send/receive */
414
415 error = ETIMEDOUT;
416 goto out;
417
418 gotreply:
419
420 /*
421 * Get RPC reply header into first mbuf,
422 * get its length, then strip it off.
423 */
424 len = sizeof(*reply);
425 if (m->m_len < len) {
426 m = m_pullup(m, len);
427 if (m == NULL) {
428 error = ENOBUFS;
429 goto out;
430 }
431 }
432 reply = mtod(m, struct rpc_reply *);
433 if (reply->rp_auth.authtype != 0) {
434 len += fxdr_unsigned(u_int32_t, reply->rp_auth.authlen);
435 len = (len + 3) & ~3; /* XXX? */
436 }
437 m_adj(m, len);
438
439 /* result */
440 *data = m;
441 if (from_p) {
442 *from_p = from;
443 from = NULL;
444 }
445
446 out:
447 if (nam) m_freem(nam);
448 if (mhead) m_freem(mhead);
449 if (from) m_freem(from);
450 soclose(so);
451 return error;
452 }
453
454 /*
455 * eXternal Data Representation routines.
456 * (but with non-standard args...)
457 */
458
459 /*
460 * String representation for RPC.
461 */
462 struct xdr_string {
463 u_int32_t len; /* length without null or padding */
464 char data[4]; /* data (longer, of course) */
465 /* data is padded to a long-word boundary */
466 };
467
468 struct mbuf *
469 xdr_string_encode(str, len)
470 char *str;
471 int len;
472 {
473 struct mbuf *m;
474 struct xdr_string *xs;
475 int dlen; /* padded string length */
476 int mlen; /* message length */
477
478 dlen = (len + 3) & ~3;
479 mlen = dlen + 4;
480
481 if (mlen > MCLBYTES) /* If too big, we just can't do it. */
482 return (NULL);
483
484 m = m_get(M_WAIT, MT_DATA);
485 if (mlen > MLEN) {
486 MCLGET(m, M_WAIT);
487 if ((m->m_flags & M_EXT) == 0) {
488 (void) m_free(m); /* There can be only one. */
489 return (NULL);
490 }
491 }
492 xs = mtod(m, struct xdr_string *);
493 m->m_len = mlen;
494 xs->len = txdr_unsigned(len);
495 bcopy(str, xs->data, len);
496 return (m);
497 }
498
499 struct mbuf *
500 xdr_string_decode(m, str, len_p)
501 struct mbuf *m;
502 char *str;
503 int *len_p; /* bufsize - 1 */
504 {
505 struct xdr_string *xs;
506 int mlen; /* message length */
507 int slen; /* string length */
508
509 if (m->m_len < 4) {
510 m = m_pullup(m, 4);
511 if (m == NULL)
512 return (NULL);
513 }
514 xs = mtod(m, struct xdr_string *);
515 slen = fxdr_unsigned(u_int32_t, xs->len);
516 mlen = 4 + ((slen + 3) & ~3);
517
518 if (slen > *len_p)
519 slen = *len_p;
520 if (slen > m->m_pkthdr.len) {
521 m_freem(m);
522 return (NULL);
523 }
524 m_copydata(m, 4, slen, str);
525 m_adj(m, mlen);
526
527 str[slen] = '\0';
528 *len_p = slen;
529
530 return (m);
531 }
532
533
534 /*
535 * Inet address in RPC messages
536 * (Note, really four ints, NOT chars. Blech.)
537 */
538 struct xdr_inaddr {
539 u_int32_t atype;
540 u_int32_t addr[4];
541 };
542
543 struct mbuf *
544 xdr_inaddr_encode(ia)
545 struct in_addr *ia; /* already in network order */
546 {
547 struct mbuf *m;
548 struct xdr_inaddr *xi;
549 u_int8_t *cp;
550 u_int32_t *ip;
551
552 m = m_get(M_WAIT, MT_DATA);
553 xi = mtod(m, struct xdr_inaddr *);
554 m->m_len = sizeof(*xi);
555 xi->atype = txdr_unsigned(1);
556 ip = xi->addr;
557 cp = (u_int8_t *)&ia->s_addr;
558 *ip++ = txdr_unsigned(*cp++);
559 *ip++ = txdr_unsigned(*cp++);
560 *ip++ = txdr_unsigned(*cp++);
561 *ip++ = txdr_unsigned(*cp++);
562
563 return (m);
564 }
565
566 struct mbuf *
567 xdr_inaddr_decode(m, ia)
568 struct mbuf *m;
569 struct in_addr *ia; /* already in network order */
570 {
571 struct xdr_inaddr *xi;
572 u_int8_t *cp;
573 u_int32_t *ip;
574
575 if (m->m_len < sizeof(*xi)) {
576 m = m_pullup(m, sizeof(*xi));
577 if (m == NULL)
578 return (NULL);
579 }
580 xi = mtod(m, struct xdr_inaddr *);
581 if (xi->atype != txdr_unsigned(1)) {
582 ia->s_addr = INADDR_ANY;
583 goto out;
584 }
585 ip = xi->addr;
586 cp = (u_int8_t *)&ia->s_addr;
587 *cp++ = fxdr_unsigned(u_int8_t, *ip++);
588 *cp++ = fxdr_unsigned(u_int8_t, *ip++);
589 *cp++ = fxdr_unsigned(u_int8_t, *ip++);
590 *cp++ = fxdr_unsigned(u_int8_t, *ip++);
591
592 out:
593 m_adj(m, sizeof(*xi));
594 return (m);
595 }