rpc.c revision 1.23 1 /* $NetBSD: rpc.c,v 1.23 2003/08/31 22:40:49 fvdl Exp $ */
2
3 /*
4 * Copyright (c) 1992 Regents of the University of California.
5 * All rights reserved.
6 *
7 * This software was developed by the Computer Systems Engineering group
8 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
9 * contributed to Berkeley.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. All advertising materials mentioning features or use of this software
20 * must display the following acknowledgement:
21 * This product includes software developed by the University of
22 * California, Lawrence Berkeley Laboratory and its contributors.
23 * 4. Neither the name of the University nor the names of its contributors
24 * may be used to endorse or promote products derived from this software
25 * without specific prior written permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37 * SUCH DAMAGE.
38 *
39 * @(#) Header: rpc.c,v 1.12 93/09/28 08:31:56 leres Exp (LBL)
40 */
41
42 /*
43 * RPC functions used by NFS and bootparams.
44 * Note that bootparams requires the ability to find out the
45 * address of the server from which its response has come.
46 * This is supported by keeping the IP/UDP headers in the
47 * buffer space provided by the caller. (See rpc_fromaddr)
48 */
49
50 #include <sys/param.h>
51 #include <sys/socket.h>
52
53 #include <netinet/in.h>
54 #include <netinet/in_systm.h>
55
56 #ifdef _STANDALONE
57 #include <lib/libkern/libkern.h>
58 #else
59 #include <string.h>
60 #endif
61
62 #include "rpcv2.h"
63
64 #include "stand.h"
65 #include "net.h"
66 #include "rpc.h"
67
68 struct auth_info {
69 int32_t authtype; /* auth type */
70 u_int32_t authlen; /* auth length */
71 };
72
73 struct auth_unix {
74 int32_t ua_time;
75 int32_t ua_hostname; /* null */
76 int32_t ua_uid;
77 int32_t ua_gid;
78 int32_t ua_gidlist; /* null */
79 };
80
81 struct rpc_call {
82 u_int32_t rp_xid; /* request transaction id */
83 int32_t rp_direction; /* call direction (0) */
84 u_int32_t rp_rpcvers; /* rpc version (2) */
85 u_int32_t rp_prog; /* program */
86 u_int32_t rp_vers; /* version */
87 u_int32_t rp_proc; /* procedure */
88 };
89
90 struct rpc_reply {
91 u_int32_t rp_xid; /* request transaction id */
92 int32_t rp_direction; /* call direction (1) */
93 int32_t rp_astatus; /* accept status (0: accepted) */
94 union {
95 u_int32_t rpu_errno;
96 struct {
97 struct auth_info rok_auth;
98 u_int32_t rok_status;
99 } rpu_rok;
100 } rp_u;
101 };
102
103 /* Local forwards */
104 static ssize_t recvrpc __P((struct iodesc *, void *, size_t, time_t));
105 static int rpc_getport __P((struct iodesc *, n_long, n_long));
106
107 int rpc_xid;
108 int rpc_port = 0x400; /* predecrement */
109
110 /*
111 * Make a rpc call; return length of answer
112 * Note: Caller must leave room for headers.
113 */
114 ssize_t
115 rpc_call(d, prog, vers, proc, sdata, slen, rdata, rlen)
116 struct iodesc *d;
117 n_long prog, vers, proc;
118 void *sdata;
119 size_t slen;
120 void *rdata;
121 size_t rlen;
122 {
123 ssize_t cc;
124 struct auth_info *auth;
125 struct rpc_call *call;
126 struct rpc_reply *reply;
127 char *send_head, *send_tail;
128 char *recv_head, *recv_tail;
129 n_long x;
130 int port; /* host order */
131
132 #ifdef RPC_DEBUG
133 if (debug)
134 printf("rpc_call: prog=0x%x vers=%d proc=%d\n",
135 prog, vers, proc);
136 #endif
137
138 port = rpc_getport(d, prog, vers);
139 if (port == -1)
140 return (-1);
141
142 d->destport = htons(port);
143
144 /*
145 * Prepend authorization stuff and headers.
146 * Note, must prepend things in reverse order.
147 */
148 send_head = sdata;
149 send_tail = (char *)sdata + slen;
150
151 /* Auth verifier is always auth_null */
152 send_head -= sizeof(*auth);
153 auth = (struct auth_info *)send_head;
154 auth->authtype = htonl(RPCAUTH_NULL);
155 auth->authlen = 0;
156
157 #if 1
158 /* Auth credentials: always auth unix (as root) */
159 send_head -= sizeof(struct auth_unix);
160 bzero(send_head, sizeof(struct auth_unix));
161 send_head -= sizeof(*auth);
162 auth = (struct auth_info *)send_head;
163 auth->authtype = htonl(RPCAUTH_UNIX);
164 auth->authlen = htonl(sizeof(struct auth_unix));
165 #else
166 /* Auth credentials: always auth_null (XXX OK?) */
167 send_head -= sizeof(*auth);
168 auth = send_head;
169 auth->authtype = htonl(RPCAUTH_NULL);
170 auth->authlen = 0;
171 #endif
172
173 /* RPC call structure. */
174 send_head -= sizeof(*call);
175 call = (struct rpc_call *)send_head;
176 rpc_xid++;
177 call->rp_xid = htonl(rpc_xid);
178 call->rp_direction = htonl(RPC_CALL);
179 call->rp_rpcvers = htonl(RPC_VER2);
180 call->rp_prog = htonl(prog);
181 call->rp_vers = htonl(vers);
182 call->rp_proc = htonl(proc);
183
184 /* Make room for the rpc_reply header. */
185 recv_head = rdata;
186 recv_tail = (char *)rdata + rlen;
187 recv_head -= sizeof(*reply);
188
189 cc = sendrecv(d,
190 sendudp, send_head, send_tail - send_head,
191 recvrpc, recv_head, recv_tail - recv_head);
192
193 #ifdef RPC_DEBUG
194 if (debug)
195 printf("callrpc: cc=%ld rlen=%lu\n", (long)cc, (u_long)rlen);
196 #endif
197 if (cc == -1)
198 return (-1);
199
200 if ((size_t)cc <= sizeof(*reply)) {
201 errno = EBADRPC;
202 return (-1);
203 }
204
205 recv_tail = recv_head + cc;
206
207 /*
208 * Check the RPC reply status.
209 * The xid, dir, astatus were already checked.
210 */
211 reply = (struct rpc_reply *)recv_head;
212 auth = &reply->rp_u.rpu_rok.rok_auth;
213 x = ntohl(auth->authlen);
214 if (x != 0) {
215 #ifdef RPC_DEBUG
216 if (debug)
217 printf("callrpc: reply auth != NULL\n");
218 #endif
219 errno = EBADRPC;
220 return(-1);
221 }
222 x = ntohl(reply->rp_u.rpu_rok.rok_status);
223 if (x != 0) {
224 printf("callrpc: error = %d\n", x);
225 errno = EBADRPC;
226 return(-1);
227 }
228 recv_head += sizeof(*reply);
229
230 return (ssize_t)(recv_tail - recv_head);
231 }
232
233 /*
234 * Returns true if packet is the one we're waiting for.
235 * This just checks the XID, direction, acceptance.
236 * Remaining checks are done by callrpc
237 */
238 static ssize_t
239 recvrpc(d, pkt, len, tleft)
240 struct iodesc *d;
241 void *pkt;
242 size_t len;
243 time_t tleft;
244 {
245 struct rpc_reply *reply;
246 ssize_t n;
247 int x;
248
249 errno = 0;
250 #ifdef RPC_DEBUG
251 if (debug)
252 printf("recvrpc: called len=%lu\n", (u_long)len);
253 #endif
254
255 n = readudp(d, pkt, len, tleft);
256 if (n <= (4 * 4))
257 return -1;
258
259 reply = (struct rpc_reply *)pkt;
260
261 x = ntohl(reply->rp_xid);
262 if (x != rpc_xid) {
263 #ifdef RPC_DEBUG
264 if (debug)
265 printf("recvrpc: rp_xid %d != xid %d\n", x, rpc_xid);
266 #endif
267 return -1;
268 }
269
270 x = ntohl(reply->rp_direction);
271 if (x != RPC_REPLY) {
272 #ifdef RPC_DEBUG
273 if (debug)
274 printf("recvrpc: rp_direction %d != REPLY\n", x);
275 #endif
276 return -1;
277 }
278
279 x = ntohl(reply->rp_astatus);
280 if (x != RPC_MSGACCEPTED) {
281 errno = ntohl(reply->rp_u.rpu_errno);
282 printf("recvrpc: reject, astat=%d, errno=%d\n", x, errno);
283 return -1;
284 }
285
286 /* Return data count (thus indicating success) */
287 return (n);
288 }
289
290 /*
291 * Given a pointer to a reply just received,
292 * dig out the IP address/port from the headers.
293 */
294 void
295 rpc_fromaddr(pkt, addr, port)
296 void *pkt;
297 struct in_addr *addr;
298 u_short *port;
299 {
300 struct hackhdr {
301 /* Tail of IP header: just IP addresses */
302 n_long ip_src;
303 n_long ip_dst;
304 /* UDP header: */
305 u_int16_t uh_sport; /* source port */
306 u_int16_t uh_dport; /* destination port */
307 int16_t uh_ulen; /* udp length */
308 u_int16_t uh_sum; /* udp checksum */
309 /* RPC reply header: */
310 struct rpc_reply rpc;
311 } *hhdr;
312
313 hhdr = ((struct hackhdr *)pkt) - 1;
314 addr->s_addr = hhdr->ip_src;
315 *port = hhdr->uh_sport;
316 }
317
318 /*
319 * RPC Portmapper cache
320 */
321 #define PMAP_NUM 8 /* need at most 5 pmap entries */
322
323 int rpc_pmap_num;
324 struct pmap_list {
325 struct in_addr addr; /* server, net order */
326 u_int prog; /* host order */
327 u_int vers; /* host order */
328 int port; /* host order */
329 } rpc_pmap_list[PMAP_NUM];
330
331 /* return port number in host order, or -1 */
332 int
333 rpc_pmap_getcache(addr, prog, vers)
334 struct in_addr addr; /* server, net order */
335 u_int prog; /* host order */
336 u_int vers; /* host order */
337 {
338 struct pmap_list *pl;
339
340 for (pl = rpc_pmap_list; pl < &rpc_pmap_list[rpc_pmap_num]; pl++) {
341 if (pl->addr.s_addr == addr.s_addr &&
342 pl->prog == prog && pl->vers == vers )
343 {
344 return (pl->port);
345 }
346 }
347 return (-1);
348 }
349
350 void
351 rpc_pmap_putcache(addr, prog, vers, port)
352 struct in_addr addr; /* server, net order */
353 u_int prog; /* host order */
354 u_int vers; /* host order */
355 int port; /* host order */
356 {
357 struct pmap_list *pl;
358
359 /* Don't overflow cache... */
360 if (rpc_pmap_num >= PMAP_NUM) {
361 /* ... just re-use the last entry. */
362 rpc_pmap_num = PMAP_NUM - 1;
363 #ifdef RPC_DEBUG
364 printf("rpc_pmap_putcache: cache overflow\n");
365 #endif
366 }
367
368 pl = &rpc_pmap_list[rpc_pmap_num];
369 rpc_pmap_num++;
370
371 /* Cache answer */
372 pl->addr = addr;
373 pl->prog = prog;
374 pl->vers = vers;
375 pl->port = port;
376 }
377
378
379 /*
380 * Request a port number from the port mapper.
381 * Returns the port in host order.
382 */
383 int
384 rpc_getport(d, prog, vers)
385 struct iodesc *d;
386 n_long prog; /* host order */
387 n_long vers; /* host order */
388 {
389 struct args {
390 n_long prog; /* call program */
391 n_long vers; /* call version */
392 n_long proto; /* call protocol */
393 n_long port; /* call port (unused) */
394 } *args;
395 struct res {
396 n_long port;
397 } *res;
398 struct {
399 n_long h[RPC_HEADER_WORDS];
400 struct args d;
401 } sdata;
402 struct {
403 n_long h[RPC_HEADER_WORDS];
404 struct res d;
405 n_long pad;
406 } rdata;
407 ssize_t cc;
408 int port;
409
410 #ifdef RPC_DEBUG
411 if (debug)
412 printf("getport: prog=0x%x vers=%d\n", prog, vers);
413 #endif
414
415 /* This one is fixed forever. */
416 if (prog == PMAPPROG)
417 return (PMAPPORT);
418
419 /* Try for cached answer first */
420 port = rpc_pmap_getcache(d->destip, prog, vers);
421 if (port != -1)
422 return (port);
423
424 args = &sdata.d;
425 args->prog = htonl(prog);
426 args->vers = htonl(vers);
427 args->proto = htonl(IPPROTO_UDP);
428 args->port = 0;
429 res = &rdata.d;
430
431 cc = rpc_call(d, PMAPPROG, PMAPVERS, PMAPPROC_GETPORT,
432 args, sizeof(*args), res, sizeof(*res));
433 if ((size_t)cc < sizeof(*res)) {
434 printf("getport: %s", strerror(errno));
435 errno = EBADRPC;
436 return (-1);
437 }
438 port = (int)ntohl(res->port);
439
440 rpc_pmap_putcache(d->destip, prog, vers, port);
441
442 return (port);
443 }
444