xref: /freebsd/lib/libc/rpc/svc.c (revision daf1cffce2e07931f27c6c6998652e90df6ba87e)
1 /*
2  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
3  * unrestricted use provided that this legend is included on all tape
4  * media and as a part of the software program in whole or part.  Users
5  * may copy or modify Sun RPC without charge, but are not authorized
6  * to license or distribute it to anyone else except as part of a product or
7  * program developed by the user.
8  *
9  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
10  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
11  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
12  *
13  * Sun RPC is provided with no support and without any obligation on the
14  * part of Sun Microsystems, Inc. to assist in its use, correction,
15  * modification or enhancement.
16  *
17  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
18  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
19  * OR ANY PART THEREOF.
20  *
21  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
22  * or profits or other special, indirect and consequential damages, even if
23  * Sun has been advised of the possibility of such damages.
24  *
25  * Sun Microsystems, Inc.
26  * 2550 Garcia Avenue
27  * Mountain View, California  94043
28  */
29 
30 #if defined(LIBC_SCCS) && !defined(lint)
31 /*static char *sccsid = "from: @(#)svc.c 1.44 88/02/08 Copyr 1984 Sun Micro";*/
32 /*static char *sccsid = "from: @(#)svc.c	2.4 88/08/11 4.0 RPCSRC";*/
33 static char *rcsid = "$FreeBSD$";
34 #endif
35 
36 /*
37  * svc.c, Server-side remote procedure call interface.
38  *
39  * There are two sets of procedures here.  The xprt routines are
40  * for handling transport handles.  The svc routines handle the
41  * list of service routines.
42  *
43  * Copyright (C) 1984, Sun Microsystems, Inc.
44  */
45 
46 #include <string.h>
47 #include <stdlib.h>
48 #include <sys/errno.h>
49 #include <rpc/rpc.h>
50 #include <rpc/pmap_clnt.h>
51 
52 static SVCXPRT **xports;
53 static int xportssize;
54 
55 #define NULL_SVC ((struct svc_callout *)0)
56 #define	RQCRED_SIZE	400		/* this size is excessive */
57 
58 #define max(a, b) (a > b ? a : b)
59 
60 /*
61  * The services list
62  * Each entry represents a set of procedures (an rpc program).
63  * The dispatch routine takes request structs and runs the
64  * apropriate procedure.
65  */
66 static struct svc_callout {
67 	struct svc_callout *sc_next;
68 	u_long		    sc_prog;
69 	u_long		    sc_vers;
70 	void		    (*sc_dispatch)();
71 } *svc_head;
72 
73 static struct svc_callout *svc_find();
74 
75 int __svc_fdsetsize = 0;
76 fd_set *__svc_fdset = NULL;
77 
78 /* ***************  SVCXPRT related stuff **************** */
79 
80 /*
81  * Activate a transport handle.
82  */
83 void
84 xprt_register(xprt)
85 	SVCXPRT *xprt;
86 {
87 	register int sock = xprt->xp_sock;
88 
89 	if (sock + 1 > __svc_fdsetsize) {
90 		int bytes = howmany(sock + 1, NFDBITS) * sizeof(fd_mask);
91 		fd_set *fds;
92 
93 		fds = (fd_set *)malloc(bytes);
94 		memset(fds, 0, bytes);
95 		if (__svc_fdset) {
96 			memcpy(fds, __svc_fdset, howmany(__svc_fdsetsize,
97 				NFDBITS) * sizeof(fd_mask));
98 			free(__svc_fdset);
99 		}
100 		__svc_fdset = fds;
101 		__svc_fdsetsize = howmany(sock+1, NFDBITS) * NFDBITS;
102 	}
103 
104 	if (sock < FD_SETSIZE)
105 		FD_SET(sock, &svc_fdset);
106 	FD_SET(sock, __svc_fdset);
107 
108 	if (xports == NULL || sock + 1 > xportssize) {
109 		SVCXPRT **xp;
110 		int size = FD_SETSIZE;
111 
112 		if (sock + 1 > size)
113 			size = sock + 1;
114 		xp = (SVCXPRT **)mem_alloc(size * sizeof(SVCXPRT *));
115 		memset(xp, 0, size * sizeof(SVCXPRT *));
116 		if (xports) {
117 			memcpy(xp, xports, xportssize * sizeof(SVCXPRT *));
118 			free(xports);
119 		}
120 		xportssize = size;
121 		xports = xp;
122 	}
123 	xports[sock] = xprt;
124 	svc_maxfd = max(svc_maxfd, sock);
125 }
126 
127 /*
128  * De-activate a transport handle.
129  */
130 void
131 xprt_unregister(xprt)
132 	SVCXPRT *xprt;
133 {
134 	register int sock = xprt->xp_sock;
135 
136 	if (xports[sock] == xprt) {
137 		xports[sock] = (SVCXPRT *)0;
138 		if (sock < FD_SETSIZE)
139 			FD_CLR(sock, &svc_fdset);
140 		FD_CLR(sock, __svc_fdset);
141 		if (sock == svc_maxfd) {
142 			for (svc_maxfd--; svc_maxfd >= 0; svc_maxfd--)
143 				if (xports[svc_maxfd])
144 					break;
145 		}
146 		/*
147 		 * XXX could use svc_maxfd as a hint to
148 		 * decrease the size of __svc_fdset
149 		 */
150 	}
151 }
152 
153 
154 /* ********************** CALLOUT list related stuff ************* */
155 
156 /*
157  * Add a service program to the callout list.
158  * The dispatch routine will be called when a rpc request for this
159  * program number comes in.
160  */
161 bool_t
162 svc_register(xprt, prog, vers, dispatch, protocol)
163 	SVCXPRT *xprt;
164 	u_long prog;
165 	u_long vers;
166 	void (*dispatch)();
167 	int protocol;
168 {
169 	struct svc_callout *prev;
170 	register struct svc_callout *s;
171 
172 	if ((s = svc_find(prog, vers, &prev)) != NULL_SVC) {
173 		if (s->sc_dispatch == dispatch)
174 			goto pmap_it;  /* he is registering another xptr */
175 		return (FALSE);
176 	}
177 	s = (struct svc_callout *)mem_alloc(sizeof(struct svc_callout));
178 	if (s == (struct svc_callout *)0) {
179 		return (FALSE);
180 	}
181 	s->sc_prog = prog;
182 	s->sc_vers = vers;
183 	s->sc_dispatch = dispatch;
184 	s->sc_next = svc_head;
185 	svc_head = s;
186 pmap_it:
187 	/* now register the information with the local binder service */
188 	if (protocol) {
189 		return (pmap_set(prog, vers, protocol, xprt->xp_port));
190 	}
191 	return (TRUE);
192 }
193 
194 /*
195  * Remove a service program from the callout list.
196  */
197 void
198 svc_unregister(prog, vers)
199 	u_long prog;
200 	u_long vers;
201 {
202 	struct svc_callout *prev;
203 	register struct svc_callout *s;
204 
205 	if ((s = svc_find(prog, vers, &prev)) == NULL_SVC)
206 		return;
207 	if (prev == NULL_SVC) {
208 		svc_head = s->sc_next;
209 	} else {
210 		prev->sc_next = s->sc_next;
211 	}
212 	s->sc_next = NULL_SVC;
213 	mem_free((char *) s, (u_int) sizeof(struct svc_callout));
214 	/* now unregister the information with the local binder service */
215 	(void)pmap_unset(prog, vers);
216 }
217 
218 /*
219  * Search the callout list for a program number, return the callout
220  * struct.
221  */
222 static struct svc_callout *
223 svc_find(prog, vers, prev)
224 	u_long prog;
225 	u_long vers;
226 	struct svc_callout **prev;
227 {
228 	register struct svc_callout *s, *p;
229 
230 	p = NULL_SVC;
231 	for (s = svc_head; s != NULL_SVC; s = s->sc_next) {
232 		if ((s->sc_prog == prog) && (s->sc_vers == vers))
233 			goto done;
234 		p = s;
235 	}
236 done:
237 	*prev = p;
238 	return (s);
239 }
240 
241 /* ******************* REPLY GENERATION ROUTINES  ************ */
242 
243 /*
244  * Send a reply to an rpc request
245  */
246 bool_t
247 svc_sendreply(xprt, xdr_results, xdr_location)
248 	register SVCXPRT *xprt;
249 	xdrproc_t xdr_results;
250 	caddr_t xdr_location;
251 {
252 	struct rpc_msg rply;
253 
254 	rply.rm_direction = REPLY;
255 	rply.rm_reply.rp_stat = MSG_ACCEPTED;
256 	rply.acpted_rply.ar_verf = xprt->xp_verf;
257 	rply.acpted_rply.ar_stat = SUCCESS;
258 	rply.acpted_rply.ar_results.where = xdr_location;
259 	rply.acpted_rply.ar_results.proc = xdr_results;
260 	return (SVC_REPLY(xprt, &rply));
261 }
262 
263 /*
264  * No procedure error reply
265  */
266 void
267 svcerr_noproc(xprt)
268 	register SVCXPRT *xprt;
269 {
270 	struct rpc_msg rply;
271 
272 	rply.rm_direction = REPLY;
273 	rply.rm_reply.rp_stat = MSG_ACCEPTED;
274 	rply.acpted_rply.ar_verf = xprt->xp_verf;
275 	rply.acpted_rply.ar_stat = PROC_UNAVAIL;
276 	SVC_REPLY(xprt, &rply);
277 }
278 
279 /*
280  * Can't decode args error reply
281  */
282 void
283 svcerr_decode(xprt)
284 	register SVCXPRT *xprt;
285 {
286 	struct rpc_msg rply;
287 
288 	rply.rm_direction = REPLY;
289 	rply.rm_reply.rp_stat = MSG_ACCEPTED;
290 	rply.acpted_rply.ar_verf = xprt->xp_verf;
291 	rply.acpted_rply.ar_stat = GARBAGE_ARGS;
292 	SVC_REPLY(xprt, &rply);
293 }
294 
295 /*
296  * Some system error
297  */
298 void
299 svcerr_systemerr(xprt)
300 	register SVCXPRT *xprt;
301 {
302 	struct rpc_msg rply;
303 
304 	rply.rm_direction = REPLY;
305 	rply.rm_reply.rp_stat = MSG_ACCEPTED;
306 	rply.acpted_rply.ar_verf = xprt->xp_verf;
307 	rply.acpted_rply.ar_stat = SYSTEM_ERR;
308 	SVC_REPLY(xprt, &rply);
309 }
310 
311 /*
312  * Authentication error reply
313  */
314 void
315 svcerr_auth(xprt, why)
316 	SVCXPRT *xprt;
317 	enum auth_stat why;
318 {
319 	struct rpc_msg rply;
320 
321 	rply.rm_direction = REPLY;
322 	rply.rm_reply.rp_stat = MSG_DENIED;
323 	rply.rjcted_rply.rj_stat = AUTH_ERROR;
324 	rply.rjcted_rply.rj_why = why;
325 	SVC_REPLY(xprt, &rply);
326 }
327 
328 /*
329  * Auth too weak error reply
330  */
331 void
332 svcerr_weakauth(xprt)
333 	SVCXPRT *xprt;
334 {
335 
336 	svcerr_auth(xprt, AUTH_TOOWEAK);
337 }
338 
339 /*
340  * Program unavailable error reply
341  */
342 void
343 svcerr_noprog(xprt)
344 	register SVCXPRT *xprt;
345 {
346 	struct rpc_msg rply;
347 
348 	rply.rm_direction = REPLY;
349 	rply.rm_reply.rp_stat = MSG_ACCEPTED;
350 	rply.acpted_rply.ar_verf = xprt->xp_verf;
351 	rply.acpted_rply.ar_stat = PROG_UNAVAIL;
352 	SVC_REPLY(xprt, &rply);
353 }
354 
355 /*
356  * Program version mismatch error reply
357  */
358 void
359 svcerr_progvers(xprt, low_vers, high_vers)
360 	register SVCXPRT *xprt;
361 	u_long low_vers;
362 	u_long high_vers;
363 {
364 	struct rpc_msg rply;
365 
366 	rply.rm_direction = REPLY;
367 	rply.rm_reply.rp_stat = MSG_ACCEPTED;
368 	rply.acpted_rply.ar_verf = xprt->xp_verf;
369 	rply.acpted_rply.ar_stat = PROG_MISMATCH;
370 	rply.acpted_rply.ar_vers.low = low_vers;
371 	rply.acpted_rply.ar_vers.high = high_vers;
372 	SVC_REPLY(xprt, &rply);
373 }
374 
375 /* ******************* SERVER INPUT STUFF ******************* */
376 
377 /*
378  * Get server side input from some transport.
379  *
380  * Statement of authentication parameters management:
381  * This function owns and manages all authentication parameters, specifically
382  * the "raw" parameters (msg.rm_call.cb_cred and msg.rm_call.cb_verf) and
383  * the "cooked" credentials (rqst->rq_clntcred).
384  * However, this function does not know the structure of the cooked
385  * credentials, so it make the following assumptions:
386  *   a) the structure is contiguous (no pointers), and
387  *   b) the cred structure size does not exceed RQCRED_SIZE bytes.
388  * In all events, all three parameters are freed upon exit from this routine.
389  * The storage is trivially management on the call stack in user land, but
390  * is mallocated in kernel land.
391  */
392 
393 void
394 svc_getreq(rdfds)
395 	int rdfds;
396 {
397 	fd_set readfds;
398 
399 	FD_ZERO(&readfds);
400 	readfds.fds_bits[0] = rdfds;
401 	svc_getreqset(&readfds);
402 }
403 
404 void
405 svc_getreqset(readfds)
406 	fd_set *readfds;
407 {
408 	svc_getreqset2(readfds, FD_SETSIZE);
409 }
410 
411 void
412 svc_getreqset2(readfds, width)
413 	fd_set *readfds;
414 	int width;
415 {
416 	enum xprt_stat stat;
417 	struct rpc_msg msg;
418 	int prog_found;
419 	u_long low_vers;
420 	u_long high_vers;
421 	struct svc_req r;
422 	register SVCXPRT *xprt;
423 	register int bit;
424 	register int sock;
425 	register fd_mask mask, *maskp;
426 	char cred_area[2*MAX_AUTH_BYTES + RQCRED_SIZE];
427 	msg.rm_call.cb_cred.oa_base = cred_area;
428 	msg.rm_call.cb_verf.oa_base = &(cred_area[MAX_AUTH_BYTES]);
429 	r.rq_clntcred = &(cred_area[2*MAX_AUTH_BYTES]);
430 
431 
432 	maskp = readfds->fds_bits;
433 	for (sock = 0; sock < width; sock += NFDBITS) {
434 	    for (mask = *maskp++; (bit = ffs(mask)); mask ^= (1 << (bit - 1))) {
435 		/* sock has input waiting */
436 		xprt = xports[sock + bit - 1];
437 		if (xprt == NULL)
438 			/* But do we control sock? */
439 			continue;
440 		/* now receive msgs from xprtprt (support batch calls) */
441 		do {
442 			if (SVC_RECV(xprt, &msg)) {
443 
444 				/* now find the exported program and call it */
445 				register struct svc_callout *s;
446 				enum auth_stat why;
447 
448 				r.rq_xprt = xprt;
449 				r.rq_prog = msg.rm_call.cb_prog;
450 				r.rq_vers = msg.rm_call.cb_vers;
451 				r.rq_proc = msg.rm_call.cb_proc;
452 				r.rq_cred = msg.rm_call.cb_cred;
453 				/* first authenticate the message */
454 				if ((why= _authenticate(&r, &msg)) != AUTH_OK) {
455 					svcerr_auth(xprt, why);
456 					goto call_done;
457 				}
458 				/* now match message with a registered service*/
459 				prog_found = FALSE;
460 				low_vers = (u_long) - 1;
461 				high_vers = 0;
462 				for (s = svc_head; s != NULL_SVC; s = s->sc_next) {
463 					if (s->sc_prog == r.rq_prog) {
464 						if (s->sc_vers == r.rq_vers) {
465 							(*s->sc_dispatch)(&r, xprt);
466 							goto call_done;
467 						}  /* found correct version */
468 						prog_found = TRUE;
469 						if (s->sc_vers < low_vers)
470 							low_vers = s->sc_vers;
471 						if (s->sc_vers > high_vers)
472 							high_vers = s->sc_vers;
473 					}   /* found correct program */
474 				}
475 				/*
476 				 * if we got here, the program or version
477 				 * is not served ...
478 				 */
479 				if (prog_found)
480 					svcerr_progvers(xprt,
481 					low_vers, high_vers);
482 				else
483 					 svcerr_noprog(xprt);
484 				/* Fall through to ... */
485 			}
486 		call_done:
487 			if ((stat = SVC_STAT(xprt)) == XPRT_DIED){
488 				SVC_DESTROY(xprt);
489 				break;
490 			}
491 		} while (stat == XPRT_MOREREQS);
492 	    }
493 	}
494 }
495