1 /* NetBSD: krpc_subr.c,v 1.12.4.1 1996/06/07 00:52:26 cgd 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/cdefs.h>
46 /* __FBSDID("FreeBSD: head/sys/nfs/krpc_subr.c 298788 2016-04-29 16:07:25Z pfg "); */
47 __RCSID("$NetBSD: krpc_subr.c,v 1.6 2016/11/18 22:37:50 pgoyette Exp $");
48
49 #include <sys/param.h>
50 #include <sys/systm.h>
51 #include <sys/malloc.h>
52 #include <sys/mbuf.h>
53 #include <sys/proc.h>
54 #include <sys/socket.h>
55 #include <sys/socketvar.h>
56 #include <sys/uio.h>
57
58 #include <net/if.h>
59
60 #include <netinet/in.h>
61
62 #include <fs/nfs/common/krpc.h>
63 #include <fs/nfs/common/xdr_subs.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 krpc_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 krpc_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
krpc_portmap(struct sockaddr_in * sin,u_int prog,u_int vers,u_int16_t * portp,struct thread * td)131 krpc_portmap(struct sockaddr_in *sin, u_int prog, u_int vers, u_int16_t *portp,
132 struct thread *td)
133 {
134 struct sdata {
135 u_int32_t prog; /* call program */
136 u_int32_t vers; /* call version */
137 u_int32_t proto; /* call protocol */
138 u_int32_t port; /* call port (unused) */
139 } *sdata;
140 struct rdata {
141 u_int16_t pad;
142 u_int16_t port;
143 } *rdata;
144 struct mbuf *m;
145 int error;
146
147 /* The portmapper port is fixed. */
148 if (prog == PMAPPROG) {
149 *portp = htons(PMAPPORT);
150 return 0;
151 }
152
153 m = m_get(M_WAITOK, MT_DATA);
154 sdata = mtod(m, struct sdata *);
155 m->m_len = sizeof(*sdata);
156
157 /* Do the RPC to get it. */
158 sdata->prog = txdr_unsigned(prog);
159 sdata->vers = txdr_unsigned(vers);
160 sdata->proto = txdr_unsigned(IPPROTO_UDP);
161 sdata->port = 0;
162
163 sin->sin_port = htons(PMAPPORT);
164 error = krpc_call(sin, PMAPPROG, PMAPVERS,
165 PMAPPROC_GETPORT, &m, NULL, td);
166 if (error)
167 goto out;
168
169 if (m->m_len < sizeof(*rdata)) {
170 m = m_pullup(m, sizeof(*rdata));
171 if (m == NULL)
172 return ENOBUFS;
173 }
174 rdata = mtod(m, struct rdata *);
175 *portp = rdata->port;
176
177 out:
178 m_freem(m);
179 return error;
180 }
181
182 /*
183 * Do a remote procedure call (RPC) and wait for its reply.
184 * If from_p is non-null, then we are doing broadcast, and
185 * the address from whence the response came is saved there.
186 */
187 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)188 krpc_call(struct sockaddr_in *sa, u_int prog, u_int vers, u_int func,
189 struct mbuf **data, struct sockaddr **from_p, struct thread *td)
190 {
191 struct socket *so;
192 struct sockaddr_in *sin, ssin;
193 struct sockaddr *from;
194 struct mbuf *m, *nam, *mhead;
195 struct krpc_call *call;
196 struct krpc_reply *reply;
197 struct sockopt sopt;
198 struct timeval tv;
199 struct uio auio;
200 int error, rcvflg, timo, secs, len;
201 static u_int32_t xid = ~0xFF;
202 u_int16_t tport;
203 u_int32_t saddr;
204
205 /*
206 * Validate address family.
207 * Sorry, this is INET specific...
208 */
209 if (sa->sin_family != AF_INET)
210 return (EAFNOSUPPORT);
211
212 /* Free at end if not null. */
213 nam = mhead = NULL;
214 from = NULL;
215
216 /*
217 * Create socket and set its receive timeout.
218 */
219 if ((error = socreate(AF_INET, &so, SOCK_DGRAM, 0, td->td_ucred, td)))
220 return error;
221
222 tv.tv_sec = 1;
223 tv.tv_usec = 0;
224 bzero(&sopt, sizeof sopt);
225 sopt.sopt_dir = SOPT_SET;
226 sopt.sopt_level = SOL_SOCKET;
227 sopt.sopt_name = SO_RCVTIMEO;
228 sopt.sopt_val = &tv;
229 sopt.sopt_valsize = sizeof tv;
230
231 if ((error = sosetopt(so, &sopt)) != 0)
232 goto out;
233
234 /*
235 * Enable broadcast if necessary.
236 */
237 if (from_p) {
238 int on = 1;
239 sopt.sopt_name = SO_BROADCAST;
240 sopt.sopt_val = &on;
241 sopt.sopt_valsize = sizeof on;
242 if ((error = sosetopt(so, &sopt)) != 0)
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 sin = &ssin;
252 bzero(sin, sizeof *sin);
253 sin->sin_len = sizeof(*sin);
254 sin->sin_family = AF_INET;
255 sin->sin_addr.s_addr = INADDR_ANY;
256 tport = IPPORT_RESERVED;
257 do {
258 tport--;
259 sin->sin_port = htons(tport);
260 error = sobind(so, (struct sockaddr *)sin, td);
261 } while (error == EADDRINUSE &&
262 tport > IPPORT_RESERVED / 2);
263 if (error) {
264 printf("bind failed\n");
265 goto out;
266 }
267
268 /*
269 * Setup socket address for the server.
270 */
271
272 /*
273 * Prepend RPC message header.
274 */
275 mhead = m_gethdr(M_WAITOK, MT_DATA);
276 mhead->m_next = *data;
277 *data = NULL;
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 m_reset_rcvif(mhead);
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