xref: /netbsd-src/lib/libc/rpc/svc.c (revision 1394f01b4a9e99092957ca5d824d67219565d9b5)
1 /*	$NetBSD: svc.c,v 1.10 1997/07/13 20:13:20 christos Exp $	*/
2 
3 /*
4  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
5  * unrestricted use provided that this legend is included on all tape
6  * media and as a part of the software program in whole or part.  Users
7  * may copy or modify Sun RPC without charge, but are not authorized
8  * to license or distribute it to anyone else except as part of a product or
9  * program developed by the user.
10  *
11  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
12  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
13  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
14  *
15  * Sun RPC is provided with no support and without any obligation on the
16  * part of Sun Microsystems, Inc. to assist in its use, correction,
17  * modification or enhancement.
18  *
19  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
20  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
21  * OR ANY PART THEREOF.
22  *
23  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
24  * or profits or other special, indirect and consequential damages, even if
25  * Sun has been advised of the possibility of such damages.
26  *
27  * Sun Microsystems, Inc.
28  * 2550 Garcia Avenue
29  * Mountain View, California  94043
30  */
31 
32 #include <sys/cdefs.h>
33 #if defined(LIBC_SCCS) && !defined(lint)
34 #if 0
35 static char *sccsid = "@(#)svc.c 1.44 88/02/08 Copyr 1984 Sun Micro";
36 static char *sccsid = "@(#)svc.c	2.4 88/08/11 4.0 RPCSRC";
37 #else
38 __RCSID("$NetBSD: svc.c,v 1.10 1997/07/13 20:13:20 christos Exp $");
39 #endif
40 #endif
41 
42 /*
43  * svc.c, Server-side remote procedure call interface.
44  *
45  * There are two sets of procedures here.  The xprt routines are
46  * for handling transport handles.  The svc routines handle the
47  * list of service routines.
48  *
49  * Copyright (C) 1984, Sun Microsystems, Inc.
50  */
51 
52 #include <stdlib.h>
53 #include <string.h>
54 
55 #include <sys/errno.h>
56 #include <rpc/rpc.h>
57 #include <rpc/pmap_clnt.h>
58 
59 static SVCXPRT **xports;
60 
61 #define NULL_SVC ((struct svc_callout *)0)
62 #define	RQCRED_SIZE	400		/* this size is excessive */
63 
64 #define max(a, b) (a > b ? a : b)
65 
66 /*
67  * The services list
68  * Each entry represents a set of procedures (an rpc program).
69  * The dispatch routine takes request structs and runs the
70  * apropriate procedure.
71  */
72 static struct svc_callout {
73 	struct svc_callout *sc_next;
74 	u_long		    sc_prog;
75 	u_long		    sc_vers;
76 	void		    (*sc_dispatch) __P((struct svc_req *, SVCXPRT *));
77 } *svc_head;
78 
79 static struct svc_callout *svc_find __P((u_long, u_long,
80     struct svc_callout **));
81 
82 /* ***************  SVCXPRT related stuff **************** */
83 
84 /*
85  * Activate a transport handle.
86  */
87 void
88 xprt_register(xprt)
89 	SVCXPRT *xprt;
90 {
91 	register int sock = xprt->xp_sock;
92 
93 	if (xports == NULL) {
94 		xports = (SVCXPRT **)
95 			mem_alloc(FD_SETSIZE * sizeof(SVCXPRT *));
96 		memset(xports, '\0', FD_SETSIZE * sizeof(SVCXPRT *));
97 	}
98 	if (sock < FD_SETSIZE) {
99 		xports[sock] = xprt;
100 		FD_SET(sock, &svc_fdset);
101 		svc_maxfd = max(svc_maxfd, sock);
102 	}
103 }
104 
105 /*
106  * De-activate a transport handle.
107  */
108 void
109 xprt_unregister(xprt)
110 	SVCXPRT *xprt;
111 {
112 	register int sock = xprt->xp_sock;
113 
114 	if ((sock < FD_SETSIZE) && (xports[sock] == xprt)) {
115 		xports[sock] = (SVCXPRT *)0;
116 		FD_CLR(sock, &svc_fdset);
117 		if (sock == svc_maxfd) {
118 			for (svc_maxfd--; svc_maxfd>=0; svc_maxfd--)
119 				if (xports[svc_maxfd])
120 					break;
121 		}
122 	}
123 }
124 
125 
126 /* ********************** CALLOUT list related stuff ************* */
127 
128 /*
129  * Add a service program to the callout list.
130  * The dispatch routine will be called when a rpc request for this
131  * program number comes in.
132  */
133 bool_t
134 svc_register(xprt, prog, vers, dispatch, protocol)
135 	SVCXPRT *xprt;
136 	u_long prog;
137 	u_long vers;
138 	void (*dispatch) __P((struct svc_req *, SVCXPRT *));
139 	int protocol;
140 {
141 	struct svc_callout *prev;
142 	register struct svc_callout *s;
143 
144 	if ((s = svc_find(prog, vers, &prev)) != NULL_SVC) {
145 		if (s->sc_dispatch == dispatch)
146 			goto pmap_it;  /* he is registering another xptr */
147 		return (FALSE);
148 	}
149 	s = (struct svc_callout *)mem_alloc(sizeof(struct svc_callout));
150 	if (s == (struct svc_callout *)0) {
151 		return (FALSE);
152 	}
153 	s->sc_prog = prog;
154 	s->sc_vers = vers;
155 	s->sc_dispatch = dispatch;
156 	s->sc_next = svc_head;
157 	svc_head = s;
158 pmap_it:
159 	/* now register the information with the local binder service */
160 	if (protocol) {
161 		return (pmap_set(prog, vers, protocol, xprt->xp_port));
162 	}
163 	return (TRUE);
164 }
165 
166 /*
167  * Remove a service program from the callout list.
168  */
169 void
170 svc_unregister(prog, vers)
171 	u_long prog;
172 	u_long vers;
173 {
174 	struct svc_callout *prev;
175 	register struct svc_callout *s;
176 
177 	if ((s = svc_find(prog, vers, &prev)) == NULL_SVC)
178 		return;
179 	if (prev == NULL_SVC) {
180 		svc_head = s->sc_next;
181 	} else {
182 		prev->sc_next = s->sc_next;
183 	}
184 	s->sc_next = NULL_SVC;
185 	mem_free((char *) s, (u_int) sizeof(struct svc_callout));
186 	/* now unregister the information with the local binder service */
187 	(void)pmap_unset(prog, vers);
188 }
189 
190 /*
191  * Search the callout list for a program number, return the callout
192  * struct.
193  */
194 static struct svc_callout *
195 svc_find(prog, vers, prev)
196 	u_long prog;
197 	u_long vers;
198 	struct svc_callout **prev;
199 {
200 	register struct svc_callout *s, *p;
201 
202 	p = NULL_SVC;
203 	for (s = svc_head; s != NULL_SVC; s = s->sc_next) {
204 		if ((s->sc_prog == prog) && (s->sc_vers == vers))
205 			goto done;
206 		p = s;
207 	}
208 done:
209 	*prev = p;
210 	return (s);
211 }
212 
213 /* ******************* REPLY GENERATION ROUTINES  ************ */
214 
215 /*
216  * Send a reply to an rpc request
217  */
218 bool_t
219 svc_sendreply(xprt, xdr_results, xdr_location)
220 	register SVCXPRT *xprt;
221 	xdrproc_t xdr_results;
222 	caddr_t xdr_location;
223 {
224 	struct rpc_msg rply;
225 
226 	rply.rm_direction = REPLY;
227 	rply.rm_reply.rp_stat = MSG_ACCEPTED;
228 	rply.acpted_rply.ar_verf = xprt->xp_verf;
229 	rply.acpted_rply.ar_stat = SUCCESS;
230 	rply.acpted_rply.ar_results.where = xdr_location;
231 	rply.acpted_rply.ar_results.proc = xdr_results;
232 	return (SVC_REPLY(xprt, &rply));
233 }
234 
235 /*
236  * No procedure error reply
237  */
238 void
239 svcerr_noproc(xprt)
240 	register SVCXPRT *xprt;
241 {
242 	struct rpc_msg rply;
243 
244 	rply.rm_direction = REPLY;
245 	rply.rm_reply.rp_stat = MSG_ACCEPTED;
246 	rply.acpted_rply.ar_verf = xprt->xp_verf;
247 	rply.acpted_rply.ar_stat = PROC_UNAVAIL;
248 	SVC_REPLY(xprt, &rply);
249 }
250 
251 /*
252  * Can't decode args error reply
253  */
254 void
255 svcerr_decode(xprt)
256 	register SVCXPRT *xprt;
257 {
258 	struct rpc_msg rply;
259 
260 	rply.rm_direction = REPLY;
261 	rply.rm_reply.rp_stat = MSG_ACCEPTED;
262 	rply.acpted_rply.ar_verf = xprt->xp_verf;
263 	rply.acpted_rply.ar_stat = GARBAGE_ARGS;
264 	SVC_REPLY(xprt, &rply);
265 }
266 
267 /*
268  * Some system error
269  */
270 void
271 svcerr_systemerr(xprt)
272 	register SVCXPRT *xprt;
273 {
274 	struct rpc_msg rply;
275 
276 	rply.rm_direction = REPLY;
277 	rply.rm_reply.rp_stat = MSG_ACCEPTED;
278 	rply.acpted_rply.ar_verf = xprt->xp_verf;
279 	rply.acpted_rply.ar_stat = SYSTEM_ERR;
280 	SVC_REPLY(xprt, &rply);
281 }
282 
283 /*
284  * Authentication error reply
285  */
286 void
287 svcerr_auth(xprt, why)
288 	SVCXPRT *xprt;
289 	enum auth_stat why;
290 {
291 	struct rpc_msg rply;
292 
293 	rply.rm_direction = REPLY;
294 	rply.rm_reply.rp_stat = MSG_DENIED;
295 	rply.rjcted_rply.rj_stat = AUTH_ERROR;
296 	rply.rjcted_rply.rj_why = why;
297 	SVC_REPLY(xprt, &rply);
298 }
299 
300 /*
301  * Auth too weak error reply
302  */
303 void
304 svcerr_weakauth(xprt)
305 	SVCXPRT *xprt;
306 {
307 
308 	svcerr_auth(xprt, AUTH_TOOWEAK);
309 }
310 
311 /*
312  * Program unavailable error reply
313  */
314 void
315 svcerr_noprog(xprt)
316 	register SVCXPRT *xprt;
317 {
318 	struct rpc_msg rply;
319 
320 	rply.rm_direction = REPLY;
321 	rply.rm_reply.rp_stat = MSG_ACCEPTED;
322 	rply.acpted_rply.ar_verf = xprt->xp_verf;
323 	rply.acpted_rply.ar_stat = PROG_UNAVAIL;
324 	SVC_REPLY(xprt, &rply);
325 }
326 
327 /*
328  * Program version mismatch error reply
329  */
330 void
331 svcerr_progvers(xprt, low_vers, high_vers)
332 	register SVCXPRT *xprt;
333 	u_long low_vers;
334 	u_long high_vers;
335 {
336 	struct rpc_msg rply;
337 
338 	rply.rm_direction = REPLY;
339 	rply.rm_reply.rp_stat = MSG_ACCEPTED;
340 	rply.acpted_rply.ar_verf = xprt->xp_verf;
341 	rply.acpted_rply.ar_stat = PROG_MISMATCH;
342 	rply.acpted_rply.ar_vers.low = low_vers;
343 	rply.acpted_rply.ar_vers.high = high_vers;
344 	SVC_REPLY(xprt, &rply);
345 }
346 
347 /* ******************* SERVER INPUT STUFF ******************* */
348 
349 /*
350  * Get server side input from some transport.
351  *
352  * Statement of authentication parameters management:
353  * This function owns and manages all authentication parameters, specifically
354  * the "raw" parameters (msg.rm_call.cb_cred and msg.rm_call.cb_verf) and
355  * the "cooked" credentials (rqst->rq_clntcred).
356  * However, this function does not know the structure of the cooked
357  * credentials, so it make the following assumptions:
358  *   a) the structure is contiguous (no pointers), and
359  *   b) the cred structure size does not exceed RQCRED_SIZE bytes.
360  * In all events, all three parameters are freed upon exit from this routine.
361  * The storage is trivially management on the call stack in user land, but
362  * is mallocated in kernel land.
363  */
364 
365 void
366 svc_getreq(rdfds)
367 	int rdfds;
368 {
369 	fd_set readfds;
370 
371 	FD_ZERO(&readfds);
372 	readfds.fds_bits[0] = rdfds;
373 	svc_getreqset(&readfds);
374 }
375 
376 void
377 svc_getreqset(readfds)
378 	fd_set *readfds;
379 {
380 	enum xprt_stat stat;
381 	struct rpc_msg msg;
382 	int prog_found;
383 	u_long low_vers;
384 	u_long high_vers;
385 	struct svc_req r;
386 	register SVCXPRT *xprt;
387 	register int bit;
388 	register u_int32_t mask, *maskp;
389 	register int sock;
390 	char cred_area[2*MAX_AUTH_BYTES + RQCRED_SIZE];
391 	msg.rm_call.cb_cred.oa_base = cred_area;
392 	msg.rm_call.cb_verf.oa_base = &(cred_area[MAX_AUTH_BYTES]);
393 	r.rq_clntcred = &(cred_area[2*MAX_AUTH_BYTES]);
394 
395 
396 	maskp = readfds->fds_bits;
397 	for (sock = 0; sock < FD_SETSIZE; sock += NFDBITS) {
398 	    for (mask = *maskp++; (bit = ffs(mask)) != 0;
399 		mask ^= (1 << (bit - 1))) {
400 		/* sock has input waiting */
401 		xprt = xports[sock + bit - 1];
402 		if (xprt == NULL)
403 			/* But do we control sock? */
404 			continue;
405 		/* now receive msgs from xprtprt (support batch calls) */
406 		do {
407 			if (SVC_RECV(xprt, &msg)) {
408 
409 				/* now find the exported program and call it */
410 				register struct svc_callout *s;
411 				enum auth_stat why;
412 
413 				r.rq_xprt = xprt;
414 				r.rq_prog = msg.rm_call.cb_prog;
415 				r.rq_vers = msg.rm_call.cb_vers;
416 				r.rq_proc = msg.rm_call.cb_proc;
417 				r.rq_cred = msg.rm_call.cb_cred;
418 				/* first authenticate the message */
419 				if ((why= _authenticate(&r, &msg)) != AUTH_OK) {
420 					svcerr_auth(xprt, why);
421 					goto call_done;
422 				}
423 				/* now match message with a registered service*/
424 				prog_found = FALSE;
425 				low_vers = 0 - 1;
426 				high_vers = 0;
427 				for (s = svc_head; s != NULL_SVC; s = s->sc_next) {
428 					if (s->sc_prog == r.rq_prog) {
429 						if (s->sc_vers == r.rq_vers) {
430 							(*s->sc_dispatch)(&r, xprt);
431 							goto call_done;
432 						}  /* found correct version */
433 						prog_found = TRUE;
434 						if (s->sc_vers < low_vers)
435 							low_vers = s->sc_vers;
436 						if (s->sc_vers > high_vers)
437 							high_vers = s->sc_vers;
438 					}   /* found correct program */
439 				}
440 				/*
441 				 * if we got here, the program or version
442 				 * is not served ...
443 				 */
444 				if (prog_found)
445 					svcerr_progvers(xprt,
446 					low_vers, high_vers);
447 				else
448 					 svcerr_noprog(xprt);
449 				/* Fall through to ... */
450 			}
451 		call_done:
452 			if ((stat = SVC_STAT(xprt)) == XPRT_DIED){
453 				SVC_DESTROY(xprt);
454 				break;
455 			}
456 		} while (stat == XPRT_MOREREQS);
457 	    }
458 	}
459 }
460