1 /* $NetBSD: krpc_subr.c,v 1.12.4.1 1996/06/07 00:52:26 cgd Exp $ */
2
3 /*-
4 * SPDX-License-Identifier: BSD-4-Clause
5 *
6 * Copyright (c) 1995 Gordon Ross, Adam Glass
7 * Copyright (c) 1992 Regents of the University of California.
8 * All rights reserved.
9 *
10 * This software was developed by the Computer Systems Engineering group
11 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
12 * contributed to Berkeley.
13 *
14 * Redistribution and use in source and binary forms, with or without
15 * modification, are permitted provided that the following conditions
16 * are met:
17 * 1. Redistributions of source code must retain the above copyright
18 * notice, this list of conditions and the following disclaimer.
19 * 2. Redistributions in binary form must reproduce the above copyright
20 * notice, this list of conditions and the following disclaimer in the
21 * documentation and/or other materials provided with the distribution.
22 * 3. All advertising materials mentioning features or use of this software
23 * must display the following acknowledgement:
24 * This product includes software developed by the University of
25 * California, Lawrence Berkeley Laboratory and its contributors.
26 * 4. Neither the name of the University nor the names of its contributors
27 * may be used to endorse or promote products derived from this software
28 * without specific prior written permission.
29 *
30 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
31 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
32 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
33 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
34 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
35 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
36 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
37 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
38 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
39 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
40 * SUCH DAMAGE.
41 *
42 * partially based on:
43 * libnetboot/rpc.c
44 */
45
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/jail.h>
49 #include <sys/malloc.h>
50 #include <sys/mbuf.h>
51 #include <sys/proc.h>
52 #include <sys/socket.h>
53 #include <sys/socketvar.h>
54 #include <sys/uio.h>
55
56 #include <net/if.h>
57 #include <net/vnet.h>
58
59 #include <netinet/in.h>
60
61 #include <rpc/types.h>
62 #include <rpc/auth.h>
63 #include <rpc/rpc_msg.h>
64 #include <nfs/krpc.h>
65 #include <nfs/xdr_subs.h>
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 krpc_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 krpc_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 u_int32_t rpu_errno;
108 struct {
109 struct auth_info rok_auth;
110 u_int32_t rok_status;
111 } rpu_rok;
112 } rp_u;
113 };
114 #define rp_errno rp_u.rpu_errno
115 #define rp_auth rp_u.rpu_rok.rok_auth
116 #define rp_status rp_u.rpu_rok.rok_status
117
118 #define MIN_REPLY_HDR 16 /* xid, dir, astat, errno */
119
120 /*
121 * What is the longest we will wait before re-sending a request?
122 * Note this is also the frequency of "RPC timeout" messages.
123 * The re-send loop count sup linearly to this maximum, so the
124 * first complaint will happen after (1+2+3+4+5)=15 seconds.
125 */
126 #define MAX_RESEND_DELAY 5 /* seconds */
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
krpc_portmap(struct sockaddr_in * sin,u_int prog,u_int vers,u_int16_t * portp,struct thread * td)133 krpc_portmap(struct sockaddr_in *sin, u_int prog, u_int vers, u_int16_t *portp,
134 struct thread *td)
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_WAITOK, 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, td);
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
krpc_call(struct sockaddr_in * sa,u_int prog,u_int vers,u_int func,struct mbuf ** data,struct sockaddr ** from_p,struct thread * td)189 krpc_call(struct sockaddr_in *sa, u_int prog, u_int vers, u_int func,
190 struct mbuf **data, struct sockaddr **from_p, struct thread *td)
191 {
192 struct socket *so;
193 struct sockaddr_in *sin, ssin;
194 struct sockaddr *from;
195 struct mbuf *m, *mhead;
196 struct krpc_call *call;
197 struct krpc_reply *reply;
198 struct sockopt sopt;
199 struct timeval tv;
200 struct uio auio;
201 int error, rcvflg, timo, secs, len;
202 static u_int32_t xid = ~0xFF;
203 u_int16_t tport;
204 u_int32_t saddr;
205
206 /*
207 * Validate address family.
208 * Sorry, this is INET specific...
209 */
210 if (sa->sin_family != AF_INET)
211 return (EAFNOSUPPORT);
212
213 /* Free at end if not null. */
214 mhead = NULL;
215 from = NULL;
216
217 /*
218 * Create socket and set its receive timeout.
219 */
220 if ((error = socreate(AF_INET, &so, SOCK_DGRAM, 0, td->td_ucred, td)))
221 return error;
222
223 tv.tv_sec = 1;
224 tv.tv_usec = 0;
225 bzero(&sopt, sizeof sopt);
226 sopt.sopt_dir = SOPT_SET;
227 sopt.sopt_level = SOL_SOCKET;
228 sopt.sopt_name = SO_RCVTIMEO;
229 sopt.sopt_val = &tv;
230 sopt.sopt_valsize = sizeof tv;
231
232 if ((error = sosetopt(so, &sopt)) != 0)
233 goto out;
234
235 /*
236 * Enable broadcast if necessary.
237 */
238 if (from_p) {
239 int on = 1;
240 sopt.sopt_name = SO_BROADCAST;
241 sopt.sopt_val = &on;
242 sopt.sopt_valsize = sizeof on;
243 if ((error = sosetopt(so, &sopt)) != 0)
244 goto out;
245 }
246
247 /*
248 * Bind the local endpoint to a reserved port,
249 * because some NFS servers refuse requests from
250 * non-reserved (non-privileged) ports.
251 */
252 sin = &ssin;
253 bzero(sin, sizeof *sin);
254 sin->sin_len = sizeof(*sin);
255 sin->sin_family = AF_INET;
256 sin->sin_addr.s_addr = INADDR_ANY;
257 tport = IPPORT_RESERVED;
258 do {
259 tport--;
260 sin->sin_port = htons(tport);
261 error = sobind(so, (struct sockaddr *)sin, td);
262 } while (error == EADDRINUSE &&
263 tport > IPPORT_RESERVED / 2);
264 if (error) {
265 printf("bind failed\n");
266 goto out;
267 }
268
269 /*
270 * Setup socket address for the server.
271 */
272
273 /*
274 * Prepend RPC message header.
275 */
276 mhead = m_gethdr(M_WAITOK, MT_DATA);
277 mhead->m_next = *data;
278 call = mtod(mhead, struct krpc_call *);
279 mhead->m_len = sizeof(*call);
280 bzero((caddr_t)call, sizeof(*call));
281 /* rpc_call part */
282 xid++;
283 call->rp_xid = txdr_unsigned(xid);
284 /* call->rp_direction = 0; */
285 call->rp_rpcvers = txdr_unsigned(2);
286 call->rp_prog = txdr_unsigned(prog);
287 call->rp_vers = txdr_unsigned(vers);
288 call->rp_proc = txdr_unsigned(func);
289 /* rpc_auth part (auth_unix as root) */
290 call->rpc_auth.authtype = txdr_unsigned(AUTH_UNIX);
291 call->rpc_auth.authlen = txdr_unsigned(sizeof(struct auth_unix));
292 /* rpc_verf part (auth_null) */
293 call->rpc_verf.authtype = 0;
294 call->rpc_verf.authlen = 0;
295
296 /*
297 * Setup packet header
298 */
299 m_fixhdr(mhead);
300 mhead->m_pkthdr.rcvif = NULL;
301
302 /*
303 * Send it, repeatedly, until a reply is received,
304 * but delay each re-send by an increasing amount.
305 * If the delay hits the maximum, start complaining.
306 */
307 timo = 0;
308 for (;;) {
309 /* Send RPC request (or re-send). */
310 m = m_copym(mhead, 0, M_COPYALL, M_WAITOK);
311 error = sosend(so, (struct sockaddr *)sa, NULL, m,
312 NULL, 0, td);
313 if (error) {
314 printf("krpc_call: sosend: %d\n", error);
315 goto out;
316 }
317 m = NULL;
318
319 /* Determine new timeout. */
320 if (timo < MAX_RESEND_DELAY)
321 timo++;
322 else {
323 saddr = ntohl(sa->sin_addr.s_addr);
324 printf("RPC timeout for server %d.%d.%d.%d\n",
325 (saddr >> 24) & 255,
326 (saddr >> 16) & 255,
327 (saddr >> 8) & 255,
328 saddr & 255);
329 }
330
331 /*
332 * Wait for up to timo seconds for a reply.
333 * The socket receive timeout was set to 1 second.
334 */
335 secs = timo;
336 while (secs > 0) {
337 if (from) {
338 free(from, M_SONAME);
339 from = NULL;
340 }
341 if (m) {
342 m_freem(m);
343 m = NULL;
344 }
345 bzero(&auio, sizeof(auio));
346 auio.uio_resid = len = 1<<16;
347 rcvflg = 0;
348 error = soreceive(so, &from, &auio, &m, NULL, &rcvflg);
349 if (error == EWOULDBLOCK) {
350 secs--;
351 continue;
352 }
353 if (error)
354 goto out;
355 len -= auio.uio_resid;
356
357 /* Does the reply contain at least a header? */
358 if (len < MIN_REPLY_HDR)
359 continue;
360 if (m->m_len < MIN_REPLY_HDR)
361 continue;
362 reply = mtod(m, struct krpc_reply *);
363
364 /* Is it the right reply? */
365 if (reply->rp_direction != txdr_unsigned(REPLY))
366 continue;
367
368 if (reply->rp_xid != txdr_unsigned(xid))
369 continue;
370
371 /* Was RPC accepted? (authorization OK) */
372 if (reply->rp_astatus != 0) {
373 error = fxdr_unsigned(u_int32_t, reply->rp_errno);
374 printf("rpc denied, error=%d\n", error);
375 continue;
376 }
377
378 /* Did the call succeed? */
379 if (reply->rp_status != 0) {
380 error = fxdr_unsigned(u_int32_t, reply->rp_status);
381 if (error == PROG_MISMATCH) {
382 error = EBADRPC;
383 goto out;
384 }
385 printf("rpc denied, status=%d\n", error);
386 continue;
387 }
388
389 goto gotreply; /* break two levels */
390
391 } /* while secs */
392 } /* forever send/receive */
393
394 error = ETIMEDOUT;
395 goto out;
396
397 gotreply:
398
399 /*
400 * Get RPC reply header into first mbuf,
401 * get its length, then strip it off.
402 */
403 len = sizeof(*reply);
404 if (m->m_len < len) {
405 m = m_pullup(m, len);
406 if (m == NULL) {
407 error = ENOBUFS;
408 goto out;
409 }
410 }
411 reply = mtod(m, struct krpc_reply *);
412 if (reply->rp_auth.authtype != 0) {
413 len += fxdr_unsigned(u_int32_t, reply->rp_auth.authlen);
414 len = (len + 3) & ~3; /* XXX? */
415 }
416 m_adj(m, len);
417
418 /* result */
419 *data = m;
420 if (from_p) {
421 *from_p = from;
422 from = NULL;
423 }
424
425 out:
426 if (mhead) m_freem(mhead);
427 if (from) free(from, M_SONAME);
428 soclose(so);
429 return error;
430 }
431
432 /*
433 * eXternal Data Representation routines.
434 * (but with non-standard args...)
435 */
436
437 /*
438 * String representation for RPC.
439 */
440 struct xdr_string {
441 u_int32_t len; /* length without null or padding */
442 char data[4]; /* data (longer, of course) */
443 /* data is padded to a long-word boundary */
444 };
445
446 struct mbuf *
xdr_string_encode(char * str,int len)447 xdr_string_encode(char *str, int len)
448 {
449 struct mbuf *m;
450 struct xdr_string *xs;
451 int dlen; /* padded string length */
452 int mlen; /* message length */
453
454 dlen = (len + 3) & ~3;
455 mlen = dlen + 4;
456
457 if (mlen > MCLBYTES) /* If too big, we just can't do it. */
458 return (NULL);
459
460 m = m_get2(mlen, M_WAITOK, MT_DATA, 0);
461 xs = mtod(m, struct xdr_string *);
462 m->m_len = mlen;
463 xs->len = txdr_unsigned(len);
464 bcopy(str, xs->data, len);
465 return (m);
466 }
467