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  * svc.c, Server-side remote procedure call interface.
31  *
32  * There are two sets of procedures here.  The xprt routines are
33  * for handling transport handles.  The svc routines handle the
34  * list of service routines.
35  *
36  * Copyright (C) 1984, Sun Microsystems, Inc.
37  */
38 
39 #include <errno.h>
40 #include <unistd.h>
41 #include <string.h>
42 #include "rpc_private.h"
43 #include <rpc/svc.h>
44 #include <rpc/pmap_clnt.h>
45 #include <sys/poll.h>
46 
47 /* used by svc_[max_]pollfd */
48 /* used by svc_fdset */
49 
50 #ifdef __UCLIBC_HAS_THREADS__
51 #define xports (*(SVCXPRT ***)&RPC_THREAD_VARIABLE(svc_xports_s))
52 #else
53 static SVCXPRT **xports;
54 #endif
55 
56 #define NULL_SVC ((struct svc_callout *)0)
57 #define	RQCRED_SIZE	400	/* this size is excessive */
58 
59 /* The services list
60    Each entry represents a set of procedures (an rpc program).
61    The dispatch routine takes request structs and runs the
62    appropriate procedure. */
63 struct svc_callout {
64   struct svc_callout *sc_next;
65   rpcprog_t sc_prog;
66   rpcvers_t sc_vers;
67   void (*sc_dispatch) (struct svc_req *, SVCXPRT *);
68 };
69 #ifdef __UCLIBC_HAS_THREADS__
70 #define svc_head (*(struct svc_callout **)&RPC_THREAD_VARIABLE(svc_head_s))
71 #else
72 static struct svc_callout *svc_head;
73 #endif
74 
75 /* ***************  SVCXPRT related stuff **************** */
76 
77 /* Activate a transport handle. */
78 void
xprt_register(SVCXPRT * xprt)79 xprt_register (SVCXPRT *xprt)
80 {
81   register int sock = xprt->xp_sock;
82   register int i;
83 
84   if (xports == NULL)
85     {
86       xports = (SVCXPRT **) malloc (_rpc_dtablesize () * sizeof (SVCXPRT *));
87       if (xports == NULL) /* Don�t add handle */
88 	return;
89     }
90 
91   if (sock < _rpc_dtablesize ())
92     {
93       xports[sock] = xprt;
94       if (sock < FD_SETSIZE)
95 	FD_SET (sock, &svc_fdset);
96 
97       /* Check if we have an empty slot */
98       for (i = 0; i < svc_max_pollfd; ++i)
99 	if (svc_pollfd[i].fd == -1)
100 	  {
101 	    svc_pollfd[i].fd = sock;
102 	    svc_pollfd[i].events = (POLLIN | POLLPRI |
103 				    POLLRDNORM | POLLRDBAND);
104 	    return;
105 	  }
106 
107       ++svc_max_pollfd;
108       svc_pollfd = realloc (svc_pollfd,
109 			    sizeof (struct pollfd) * svc_max_pollfd);
110       if (svc_pollfd == NULL) /* Out of memory */
111 	return;
112 
113       svc_pollfd[svc_max_pollfd - 1].fd = sock;
114       svc_pollfd[svc_max_pollfd - 1].events = (POLLIN | POLLPRI |
115 					       POLLRDNORM | POLLRDBAND);
116     }
117 }
libc_hidden_def(xprt_register)118 libc_hidden_def(xprt_register)
119 
120 /* De-activate a transport handle. */
121 void
122 xprt_unregister (SVCXPRT *xprt)
123 {
124   register int sock = xprt->xp_sock;
125   register int i;
126 
127   if ((sock < _rpc_dtablesize ()) && (xports[sock] == xprt))
128     {
129       xports[sock] = (SVCXPRT *) 0;
130 
131       if (sock < FD_SETSIZE)
132 	FD_CLR (sock, &svc_fdset);
133 
134       for (i = 0; i < svc_max_pollfd; ++i)
135 	if (svc_pollfd[i].fd == sock)
136 	  svc_pollfd[i].fd = -1;
137     }
138 }
libc_hidden_def(xprt_unregister)139 libc_hidden_def(xprt_unregister)
140 
141 
142 /* ********************** CALLOUT list related stuff ************* */
143 
144 /* Search the callout list for a program number, return the callout
145    struct. */
146 static struct svc_callout *
147 svc_find (rpcprog_t prog, rpcvers_t vers, struct svc_callout **prev)
148 {
149   register struct svc_callout *s, *p;
150 
151   p = NULL_SVC;
152   for (s = svc_head; s != NULL_SVC; s = s->sc_next)
153     {
154       if ((s->sc_prog == prog) && (s->sc_vers == vers))
155 	goto done;
156       p = s;
157     }
158 done:
159   *prev = p;
160   return s;
161 }
162 
163 /* Add a service program to the callout list.
164    The dispatch routine will be called when a rpc request for this
165    program number comes in. */
166 bool_t
svc_register(SVCXPRT * xprt,rpcprog_t prog,rpcvers_t vers,void (* dispatch)(struct svc_req *,SVCXPRT *),rpcproc_t protocol)167 svc_register (SVCXPRT * xprt, rpcprog_t prog, rpcvers_t vers,
168 	      void (*dispatch) (struct svc_req *, SVCXPRT *),
169 	      rpcproc_t protocol)
170 {
171   struct svc_callout *prev;
172   register struct svc_callout *s;
173 
174   if ((s = svc_find (prog, vers, &prev)) != NULL_SVC)
175     {
176       if (s->sc_dispatch == dispatch)
177 	goto pmap_it;		/* he is registering another xptr */
178       return FALSE;
179     }
180   s = (struct svc_callout *) mem_alloc (sizeof (struct svc_callout));
181   if (s == (struct svc_callout *) 0)
182     return FALSE;
183 
184   s->sc_prog = prog;
185   s->sc_vers = vers;
186   s->sc_dispatch = dispatch;
187   s->sc_next = svc_head;
188   svc_head = s;
189 
190 pmap_it:
191   /* now register the information with the local binder service */
192   if (protocol)
193     return pmap_set (prog, vers, protocol, xprt->xp_port);
194 
195   return TRUE;
196 }
libc_hidden_def(svc_register)197 libc_hidden_def(svc_register)
198 
199 /* Remove a service program from the callout list. */
200 void
201 svc_unregister (rpcprog_t prog, rpcvers_t vers)
202 {
203   struct svc_callout *prev;
204   register struct svc_callout *s;
205 
206   if ((s = svc_find (prog, vers, &prev)) == NULL_SVC)
207     return;
208 
209   if (prev == NULL_SVC)
210     svc_head = s->sc_next;
211   else
212     prev->sc_next = s->sc_next;
213 
214   s->sc_next = NULL_SVC;
215   mem_free ((char *) s, (u_int) sizeof (struct svc_callout));
216   /* now unregister the information with the local binder service */
217   pmap_unset (prog, vers);
218 }
libc_hidden_def(svc_unregister)219 libc_hidden_def(svc_unregister)
220 
221 /* ******************* REPLY GENERATION ROUTINES  ************ */
222 
223 /* Send a reply to an rpc request */
224 bool_t
225 svc_sendreply (register SVCXPRT *xprt, xdrproc_t xdr_results,
226 	       caddr_t xdr_location)
227 {
228   struct rpc_msg rply;
229 
230   rply.rm_direction = REPLY;
231   rply.rm_reply.rp_stat = MSG_ACCEPTED;
232   rply.acpted_rply.ar_verf = xprt->xp_verf;
233   rply.acpted_rply.ar_stat = SUCCESS;
234   rply.acpted_rply.ar_results.where = xdr_location;
235   rply.acpted_rply.ar_results.proc = xdr_results;
236   return SVC_REPLY (xprt, &rply);
237 }
libc_hidden_def(svc_sendreply)238 libc_hidden_def(svc_sendreply)
239 
240 /* No procedure error reply */
241 void
242 svcerr_noproc (register SVCXPRT *xprt)
243 {
244   struct rpc_msg rply;
245 
246   rply.rm_direction = REPLY;
247   rply.rm_reply.rp_stat = MSG_ACCEPTED;
248   rply.acpted_rply.ar_verf = xprt->xp_verf;
249   rply.acpted_rply.ar_stat = PROC_UNAVAIL;
250   SVC_REPLY (xprt, &rply);
251 }
252 
253 /* Can't decode args error reply */
254 void
svcerr_decode(register SVCXPRT * xprt)255 svcerr_decode (register SVCXPRT *xprt)
256 {
257   struct rpc_msg rply;
258 
259   rply.rm_direction = REPLY;
260   rply.rm_reply.rp_stat = MSG_ACCEPTED;
261   rply.acpted_rply.ar_verf = xprt->xp_verf;
262   rply.acpted_rply.ar_stat = GARBAGE_ARGS;
263   SVC_REPLY (xprt, &rply);
264 }
libc_hidden_def(svcerr_decode)265 libc_hidden_def(svcerr_decode)
266 
267 /* Some system error */
268 void
269 svcerr_systemerr (register SVCXPRT *xprt)
270 {
271   struct rpc_msg rply;
272 
273   rply.rm_direction = REPLY;
274   rply.rm_reply.rp_stat = MSG_ACCEPTED;
275   rply.acpted_rply.ar_verf = xprt->xp_verf;
276   rply.acpted_rply.ar_stat = SYSTEM_ERR;
277   SVC_REPLY (xprt, &rply);
278 }
279 
280 /* Authentication error reply */
281 void
svcerr_auth(SVCXPRT * xprt,enum auth_stat why)282 svcerr_auth (SVCXPRT *xprt, enum auth_stat why)
283 {
284   struct rpc_msg rply;
285 
286   rply.rm_direction = REPLY;
287   rply.rm_reply.rp_stat = MSG_DENIED;
288   rply.rjcted_rply.rj_stat = AUTH_ERROR;
289   rply.rjcted_rply.rj_why = why;
290   SVC_REPLY (xprt, &rply);
291 }
libc_hidden_def(svcerr_auth)292 libc_hidden_def(svcerr_auth)
293 
294 /* Auth too weak error reply */
295 void
296 svcerr_weakauth (SVCXPRT *xprt)
297 {
298   svcerr_auth (xprt, AUTH_TOOWEAK);
299 }
300 
301 /* Program unavailable error reply */
302 void
svcerr_noprog(register SVCXPRT * xprt)303 svcerr_noprog (register SVCXPRT *xprt)
304 {
305   struct rpc_msg rply;
306 
307   rply.rm_direction = REPLY;
308   rply.rm_reply.rp_stat = MSG_ACCEPTED;
309   rply.acpted_rply.ar_verf = xprt->xp_verf;
310   rply.acpted_rply.ar_stat = PROG_UNAVAIL;
311   SVC_REPLY (xprt, &rply);
312 }
libc_hidden_def(svcerr_noprog)313 libc_hidden_def(svcerr_noprog)
314 
315 /* Program version mismatch error reply */
316 void
317 svcerr_progvers (register SVCXPRT *xprt, rpcvers_t low_vers,
318 		 rpcvers_t high_vers)
319 {
320   struct rpc_msg rply;
321 
322   rply.rm_direction = REPLY;
323   rply.rm_reply.rp_stat = MSG_ACCEPTED;
324   rply.acpted_rply.ar_verf = xprt->xp_verf;
325   rply.acpted_rply.ar_stat = PROG_MISMATCH;
326   rply.acpted_rply.ar_vers.low = low_vers;
327   rply.acpted_rply.ar_vers.high = high_vers;
328   SVC_REPLY (xprt, &rply);
329 }
libc_hidden_def(svcerr_progvers)330 libc_hidden_def(svcerr_progvers)
331 
332 /* ******************* SERVER INPUT STUFF ******************* */
333 
334 /*
335  * Get server side input from some transport.
336  *
337  * Statement of authentication parameters management:
338  * This function owns and manages all authentication parameters, specifically
339  * the "raw" parameters (msg.rm_call.cb_cred and msg.rm_call.cb_verf) and
340  * the "cooked" credentials (rqst->rq_clntcred).
341  * However, this function does not know the structure of the cooked
342  * credentials, so it make the following assumptions:
343  *   a) the structure is contiguous (no pointers), and
344  *   b) the cred structure size does not exceed RQCRED_SIZE bytes.
345  * In all events, all three parameters are freed upon exit from this routine.
346  * The storage is trivially management on the call stack in user land, but
347  * is mallocated in kernel land.
348  */
349 
350 void
351 svc_getreq_common (const int fd)
352 {
353   enum xprt_stat stat;
354   struct rpc_msg msg;
355   register SVCXPRT *xprt;
356   char cred_area[2 * MAX_AUTH_BYTES + RQCRED_SIZE];
357   msg.rm_call.cb_cred.oa_base = cred_area;
358   msg.rm_call.cb_verf.oa_base = &(cred_area[MAX_AUTH_BYTES]);
359 
360   xprt = xports[fd];
361   /* Do we control fd? */
362   if (xprt == NULL)
363      return;
364 
365   /* now receive msgs from xprtprt (support batch calls) */
366   do
367     {
368       if (SVC_RECV (xprt, &msg))
369 	{
370 	  /* now find the exported program and call it */
371 	  struct svc_callout *s;
372 	  struct svc_req r;
373 	  enum auth_stat why;
374 	  rpcvers_t low_vers;
375 	  rpcvers_t high_vers;
376 	  int prog_found;
377 
378 	  r.rq_clntcred = &(cred_area[2 * MAX_AUTH_BYTES]);
379 	  r.rq_xprt = xprt;
380 	  r.rq_prog = msg.rm_call.cb_prog;
381 	  r.rq_vers = msg.rm_call.cb_vers;
382 	  r.rq_proc = msg.rm_call.cb_proc;
383 	  r.rq_cred = msg.rm_call.cb_cred;
384 
385 	  /* first authenticate the message */
386 	  /* Check for null flavor and bypass these calls if possible */
387 
388 	  if (msg.rm_call.cb_cred.oa_flavor == AUTH_NULL)
389 	    {
390 	      r.rq_xprt->xp_verf.oa_flavor = _null_auth.oa_flavor;
391 	      r.rq_xprt->xp_verf.oa_length = 0;
392 	    }
393 	  else if ((why = _authenticate (&r, &msg)) != AUTH_OK)
394 	    {
395 	      svcerr_auth (xprt, why);
396 	      goto call_done;
397 	    }
398 
399 	  /* now match message with a registered service */
400 	  prog_found = FALSE;
401 	  low_vers = 0 - 1;
402 	  high_vers = 0;
403 
404 	  for (s = svc_head; s != NULL_SVC; s = s->sc_next)
405 	    {
406 	      if (s->sc_prog == r.rq_prog)
407 		{
408 		  if (s->sc_vers == r.rq_vers)
409 		    {
410 		      (*s->sc_dispatch) (&r, xprt);
411 		      goto call_done;
412 		    }
413 		  /* found correct version */
414 		  prog_found = TRUE;
415 		  if (s->sc_vers < low_vers)
416 		    low_vers = s->sc_vers;
417 		  if (s->sc_vers > high_vers)
418 		    high_vers = s->sc_vers;
419 		}
420 	      /* found correct program */
421 	    }
422 	  /* if we got here, the program or version
423 	     is not served ... */
424 	  if (prog_found)
425 	    svcerr_progvers (xprt, low_vers, high_vers);
426 	  else
427 	    svcerr_noprog (xprt);
428 	  /* Fall through to ... */
429 	}
430     call_done:
431       if ((stat = SVC_STAT (xprt)) == XPRT_DIED)
432 	{
433 	  SVC_DESTROY (xprt);
434 	  break;
435 	}
436     }
437   while (stat == XPRT_MOREREQS);
438 }
libc_hidden_def(svc_getreq_common)439 libc_hidden_def(svc_getreq_common)
440 
441 void
442 svc_getreqset (fd_set *readfds)
443 {
444   register u_int32_t mask;
445   register u_int32_t *maskp;
446   register int setsize;
447   register int sock;
448   register int bit;
449 
450   setsize = _rpc_dtablesize ();
451   maskp = (u_int32_t *) readfds->fds_bits;
452   for (sock = 0; sock < setsize; sock += 32)
453     for (mask = *maskp++; (bit = ffs (mask)); mask ^= (1 << (bit - 1)))
454       svc_getreq_common (sock + bit - 1);
455 }
libc_hidden_def(svc_getreqset)456 libc_hidden_def(svc_getreqset)
457 
458 void
459 svc_getreq (int rdfds)
460 {
461   fd_set readfds;
462 
463   FD_ZERO (&readfds);
464   readfds.fds_bits[0] = rdfds;
465   svc_getreqset (&readfds);
466 }
libc_hidden_def(svc_getreq)467 libc_hidden_def(svc_getreq)
468 
469 void
470 svc_getreq_poll (struct pollfd *pfdp, int pollretval)
471 {
472   register int i;
473   register int fds_found;
474 
475   for (i = fds_found = 0; i < svc_max_pollfd && fds_found < pollretval; ++i)
476     {
477       register struct pollfd *p = &pfdp[i];
478 
479       if (p->fd != -1 && p->revents)
480 	{
481 	  /* fd has input waiting */
482 	  ++fds_found;
483 
484 	  if (p->revents & POLLNVAL)
485 	    xprt_unregister (xports[p->fd]);
486 	  else
487 	    svc_getreq_common (p->fd);
488 	}
489     }
490 }
libc_hidden_def(svc_getreq_poll)491 libc_hidden_def(svc_getreq_poll)
492 
493 #ifdef __UCLIBC_HAS_THREADS__
494 
495 void attribute_hidden __rpc_thread_svc_cleanup (void)
496 {
497   struct svc_callout *svcp;
498 
499   while ((svcp = svc_head) != NULL)
500     svc_unregister (svcp->sc_prog, svcp->sc_vers);
501 }
502 
503 #endif /* __UCLIBC_HAS_THREADS__ */
504