xref: /netbsd-src/lib/libc/rpc/svc.c (revision bada23909e740596d0a3785a73bd3583a9807fb8)
1 /*	$NetBSD: svc.c,v 1.16 1999/01/20 11:37:38 lukem 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 1.16 1999/01/20 11:37:38 lukem 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 "namespace.h"
53 
54 #include <errno.h>
55 #include <stdlib.h>
56 #include <string.h>
57 
58 #include <rpc/rpc.h>
59 #include <rpc/pmap_clnt.h>
60 
61 #ifdef __weak_alias
62 __weak_alias(svc_getreq,_svc_getreq);
63 __weak_alias(svc_getreqset,_svc_getreqset);
64 __weak_alias(svc_register,_svc_register);
65 __weak_alias(svc_sendreply,_svc_sendreply);
66 __weak_alias(svc_unregister,_svc_unregister);
67 __weak_alias(svcerr_auth,_svcerr_auth);
68 __weak_alias(svcerr_decode,_svcerr_decode);
69 __weak_alias(svcerr_noproc,_svcerr_noproc);
70 __weak_alias(svcerr_noprog,_svcerr_noprog);
71 __weak_alias(svcerr_progvers,_svcerr_progvers);
72 __weak_alias(svcerr_systemerr,_svcerr_systemerr);
73 __weak_alias(svcerr_weakauth,_svcerr_weakauth);
74 __weak_alias(xprt_register,_xprt_register);
75 __weak_alias(xprt_unregister,_xprt_unregister);
76 #endif
77 
78 static SVCXPRT **xports;
79 
80 #define NULL_SVC ((struct svc_callout *)0)
81 #define	RQCRED_SIZE	400		/* this size is excessive */
82 
83 #define max(a, b) (a > b ? a : b)
84 
85 /*
86  * The services list
87  * Each entry represents a set of procedures (an rpc program).
88  * The dispatch routine takes request structs and runs the
89  * apropriate procedure.
90  */
91 static struct svc_callout {
92 	struct svc_callout *sc_next;
93 	u_long		    sc_prog;
94 	u_long		    sc_vers;
95 	void		    (*sc_dispatch) __P((struct svc_req *, SVCXPRT *));
96 } *svc_head;
97 
98 static struct svc_callout *svc_find __P((u_long, u_long,
99     struct svc_callout **));
100 
101 /* ***************  SVCXPRT related stuff **************** */
102 
103 /*
104  * Activate a transport handle.
105  */
106 void
107 xprt_register(xprt)
108 	SVCXPRT *xprt;
109 {
110 	int sock = xprt->xp_sock;
111 
112 	if (xports == NULL) {
113 		xports = (SVCXPRT **)
114 			mem_alloc(FD_SETSIZE * sizeof(SVCXPRT *));
115 		if (xports == NULL)
116 			return;
117 		memset(xports, '\0', FD_SETSIZE * sizeof(SVCXPRT *));
118 	}
119 	if (sock < FD_SETSIZE) {
120 		xports[sock] = xprt;
121 		FD_SET(sock, &svc_fdset);
122 		svc_maxfd = max(svc_maxfd, sock);
123 	}
124 }
125 
126 /*
127  * De-activate a transport handle.
128  */
129 void
130 xprt_unregister(xprt)
131 	SVCXPRT *xprt;
132 {
133 	int sock = xprt->xp_sock;
134 
135 	if ((sock < FD_SETSIZE) && (xports[sock] == xprt)) {
136 		xports[sock] = (SVCXPRT *)0;
137 		FD_CLR(sock, &svc_fdset);
138 		if (sock == svc_maxfd) {
139 			for (svc_maxfd--; svc_maxfd>=0; svc_maxfd--)
140 				if (xports[svc_maxfd])
141 					break;
142 		}
143 	}
144 }
145 
146 
147 /* ********************** CALLOUT list related stuff ************* */
148 
149 /*
150  * Add a service program to the callout list.
151  * The dispatch routine will be called when a rpc request for this
152  * program number comes in.
153  */
154 bool_t
155 svc_register(xprt, prog, vers, dispatch, protocol)
156 	SVCXPRT *xprt;
157 	u_long prog;
158 	u_long vers;
159 	void (*dispatch) __P((struct svc_req *, SVCXPRT *));
160 	int protocol;
161 {
162 	struct svc_callout *prev;
163 	struct svc_callout *s;
164 
165 	if ((s = svc_find(prog, vers, &prev)) != NULL_SVC) {
166 		if (s->sc_dispatch == dispatch)
167 			goto pmap_it;  /* he is registering another xptr */
168 		return (FALSE);
169 	}
170 	s = (struct svc_callout *)mem_alloc(sizeof(struct svc_callout));
171 	if (s == (struct svc_callout *)0) {
172 		return (FALSE);
173 	}
174 	s->sc_prog = prog;
175 	s->sc_vers = vers;
176 	s->sc_dispatch = dispatch;
177 	s->sc_next = svc_head;
178 	svc_head = s;
179 pmap_it:
180 	/* now register the information with the local binder service */
181 	if (protocol) {
182 		return (pmap_set(prog, vers, protocol, xprt->xp_port));
183 	}
184 	return (TRUE);
185 }
186 
187 /*
188  * Remove a service program from the callout list.
189  */
190 void
191 svc_unregister(prog, vers)
192 	u_long prog;
193 	u_long vers;
194 {
195 	struct svc_callout *prev;
196 	struct svc_callout *s;
197 
198 	if ((s = svc_find(prog, vers, &prev)) == NULL_SVC)
199 		return;
200 	if (prev == NULL_SVC) {
201 		svc_head = s->sc_next;
202 	} else {
203 		prev->sc_next = s->sc_next;
204 	}
205 	s->sc_next = NULL_SVC;
206 	mem_free(s, sizeof(struct svc_callout));
207 	/* now unregister the information with the local binder service */
208 	(void)pmap_unset(prog, vers);
209 }
210 
211 /*
212  * Search the callout list for a program number, return the callout
213  * struct.
214  */
215 static struct svc_callout *
216 svc_find(prog, vers, prev)
217 	u_long prog;
218 	u_long vers;
219 	struct svc_callout **prev;
220 {
221 	struct svc_callout *s, *p;
222 
223 	p = NULL_SVC;
224 	for (s = svc_head; s != NULL_SVC; s = s->sc_next) {
225 		if ((s->sc_prog == prog) && (s->sc_vers == vers))
226 			goto done;
227 		p = s;
228 	}
229 done:
230 	*prev = p;
231 	return (s);
232 }
233 
234 /* ******************* REPLY GENERATION ROUTINES  ************ */
235 
236 /*
237  * Send a reply to an rpc request
238  */
239 bool_t
240 svc_sendreply(xprt, xdr_results, xdr_location)
241 	SVCXPRT *xprt;
242 	xdrproc_t xdr_results;
243 	caddr_t xdr_location;
244 {
245 	struct rpc_msg rply;
246 
247 	rply.rm_direction = REPLY;
248 	rply.rm_reply.rp_stat = MSG_ACCEPTED;
249 	rply.acpted_rply.ar_verf = xprt->xp_verf;
250 	rply.acpted_rply.ar_stat = SUCCESS;
251 	rply.acpted_rply.ar_results.where = xdr_location;
252 	rply.acpted_rply.ar_results.proc = xdr_results;
253 	return (SVC_REPLY(xprt, &rply));
254 }
255 
256 /*
257  * No procedure error reply
258  */
259 void
260 svcerr_noproc(xprt)
261 	SVCXPRT *xprt;
262 {
263 	struct rpc_msg rply;
264 
265 	rply.rm_direction = REPLY;
266 	rply.rm_reply.rp_stat = MSG_ACCEPTED;
267 	rply.acpted_rply.ar_verf = xprt->xp_verf;
268 	rply.acpted_rply.ar_stat = PROC_UNAVAIL;
269 	SVC_REPLY(xprt, &rply);
270 }
271 
272 /*
273  * Can't decode args error reply
274  */
275 void
276 svcerr_decode(xprt)
277 	SVCXPRT *xprt;
278 {
279 	struct rpc_msg rply;
280 
281 	rply.rm_direction = REPLY;
282 	rply.rm_reply.rp_stat = MSG_ACCEPTED;
283 	rply.acpted_rply.ar_verf = xprt->xp_verf;
284 	rply.acpted_rply.ar_stat = GARBAGE_ARGS;
285 	SVC_REPLY(xprt, &rply);
286 }
287 
288 /*
289  * Some system error
290  */
291 void
292 svcerr_systemerr(xprt)
293 	SVCXPRT *xprt;
294 {
295 	struct rpc_msg rply;
296 
297 	rply.rm_direction = REPLY;
298 	rply.rm_reply.rp_stat = MSG_ACCEPTED;
299 	rply.acpted_rply.ar_verf = xprt->xp_verf;
300 	rply.acpted_rply.ar_stat = SYSTEM_ERR;
301 	SVC_REPLY(xprt, &rply);
302 }
303 
304 /*
305  * Authentication error reply
306  */
307 void
308 svcerr_auth(xprt, why)
309 	SVCXPRT *xprt;
310 	enum auth_stat why;
311 {
312 	struct rpc_msg rply;
313 
314 	rply.rm_direction = REPLY;
315 	rply.rm_reply.rp_stat = MSG_DENIED;
316 	rply.rjcted_rply.rj_stat = AUTH_ERROR;
317 	rply.rjcted_rply.rj_why = why;
318 	SVC_REPLY(xprt, &rply);
319 }
320 
321 /*
322  * Auth too weak error reply
323  */
324 void
325 svcerr_weakauth(xprt)
326 	SVCXPRT *xprt;
327 {
328 
329 	svcerr_auth(xprt, AUTH_TOOWEAK);
330 }
331 
332 /*
333  * Program unavailable error reply
334  */
335 void
336 svcerr_noprog(xprt)
337 	SVCXPRT *xprt;
338 {
339 	struct rpc_msg rply;
340 
341 	rply.rm_direction = REPLY;
342 	rply.rm_reply.rp_stat = MSG_ACCEPTED;
343 	rply.acpted_rply.ar_verf = xprt->xp_verf;
344 	rply.acpted_rply.ar_stat = PROG_UNAVAIL;
345 	SVC_REPLY(xprt, &rply);
346 }
347 
348 /*
349  * Program version mismatch error reply
350  */
351 void
352 svcerr_progvers(xprt, low_vers, high_vers)
353 	SVCXPRT *xprt;
354 	u_long low_vers;
355 	u_long high_vers;
356 {
357 	struct rpc_msg rply;
358 
359 	rply.rm_direction = REPLY;
360 	rply.rm_reply.rp_stat = MSG_ACCEPTED;
361 	rply.acpted_rply.ar_verf = xprt->xp_verf;
362 	rply.acpted_rply.ar_stat = PROG_MISMATCH;
363 	rply.acpted_rply.ar_vers.low = (u_int32_t)low_vers;
364 	rply.acpted_rply.ar_vers.high = (u_int32_t)high_vers;
365 	SVC_REPLY(xprt, &rply);
366 }
367 
368 /* ******************* SERVER INPUT STUFF ******************* */
369 
370 /*
371  * Get server side input from some transport.
372  *
373  * Statement of authentication parameters management:
374  * This function owns and manages all authentication parameters, specifically
375  * the "raw" parameters (msg.rm_call.cb_cred and msg.rm_call.cb_verf) and
376  * the "cooked" credentials (rqst->rq_clntcred).
377  * However, this function does not know the structure of the cooked
378  * credentials, so it make the following assumptions:
379  *   a) the structure is contiguous (no pointers), and
380  *   b) the cred structure size does not exceed RQCRED_SIZE bytes.
381  * In all events, all three parameters are freed upon exit from this routine.
382  * The storage is trivially management on the call stack in user land, but
383  * is mallocated in kernel land.
384  */
385 
386 void
387 svc_getreq(rdfds)
388 	int rdfds;
389 {
390 	fd_set readfds;
391 
392 	FD_ZERO(&readfds);
393 	readfds.fds_bits[0] = rdfds;
394 	svc_getreqset(&readfds);
395 }
396 
397 void
398 svc_getreqset(readfds)
399 	fd_set *readfds;
400 {
401 	enum xprt_stat stat;
402 	struct rpc_msg msg;
403 	int prog_found;
404 	u_long low_vers;
405 	u_long high_vers;
406 	struct svc_req r;
407 	SVCXPRT *xprt;
408 	int bit;
409 	int32_t mask, *maskp;
410 	int sock;
411 	char cred_area[2*MAX_AUTH_BYTES + RQCRED_SIZE];
412 	msg.rm_call.cb_cred.oa_base = cred_area;
413 	msg.rm_call.cb_verf.oa_base = &(cred_area[MAX_AUTH_BYTES]);
414 	r.rq_clntcred = &(cred_area[2*MAX_AUTH_BYTES]);
415 
416 
417 	maskp = readfds->fds_bits;
418 	for (sock = 0; sock < FD_SETSIZE; sock += NFDBITS) {
419 	    for (mask = *maskp++; (bit = ffs(mask)) != 0;
420 		mask ^= (1 << (bit - 1))) {
421 		/* sock has input waiting */
422 		xprt = xports[sock + bit - 1];
423 		if (xprt == NULL)
424 			/* But do we control sock? */
425 			continue;
426 		/* now receive msgs from xprtprt (support batch calls) */
427 		do {
428 			if (SVC_RECV(xprt, &msg)) {
429 
430 				/* now find the exported program and call it */
431 				struct svc_callout *s;
432 				enum auth_stat why;
433 
434 				r.rq_xprt = xprt;
435 				r.rq_prog = msg.rm_call.cb_prog;
436 				r.rq_vers = msg.rm_call.cb_vers;
437 				r.rq_proc = msg.rm_call.cb_proc;
438 				r.rq_cred = msg.rm_call.cb_cred;
439 				/* first authenticate the message */
440 				if ((why= _authenticate(&r, &msg)) != AUTH_OK) {
441 					svcerr_auth(xprt, why);
442 					goto call_done;
443 				}
444 				/* now match message with a registered service*/
445 				prog_found = FALSE;
446 				low_vers = (u_long) -1L;
447 				high_vers = (u_long) 0L;
448 				for (s = svc_head; s != NULL_SVC;
449 				    s = s->sc_next) {
450 					if (s->sc_prog == r.rq_prog) {
451 						if (s->sc_vers == r.rq_vers) {
452 							(*s->sc_dispatch)(&r,
453 							    xprt);
454 							goto call_done;
455 						}  /* found correct version */
456 						prog_found = TRUE;
457 						if (s->sc_vers < low_vers)
458 							low_vers = s->sc_vers;
459 						if (s->sc_vers > high_vers)
460 							high_vers = s->sc_vers;
461 					}   /* found correct program */
462 				}
463 				/*
464 				 * if we got here, the program or version
465 				 * is not served ...
466 				 */
467 				if (prog_found)
468 					svcerr_progvers(xprt,
469 					low_vers, high_vers);
470 				else
471 					 svcerr_noprog(xprt);
472 				/* Fall through to ... */
473 			}
474 		call_done:
475 			if ((stat = SVC_STAT(xprt)) == XPRT_DIED){
476 				SVC_DESTROY(xprt);
477 				break;
478 			}
479 		} while (stat == XPRT_MOREREQS);
480 	    }
481 	}
482 }
483