sunrpc/svc.c

   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 <rpc/rpc.h>
  42 #include <rpc/svc.h>
  43 #include <rpc/pmap_clnt.h>
  44 #include <sys/poll.h>
  45
  46 #ifdef _RPC_THREAD_SAFE_
  47 #define xports RPC_THREAD_VARIABLE(svc_xports_s)
  48 #else
  49 static SVCXPRT **xports;
  50 #endif
  51
  52 #define NULL_SVC ((struct svc_callout *)0)
  53 #define RQCRED_SIZE     400     /* this size is excessive */
  54
  55 /* The services list
  56    Each entry represents a set of procedures (an rpc program).
  57    The dispatch routine takes request structs and runs the
  58    appropriate procedure. */
  59 struct svc_callout {
  60   struct svc_callout *sc_next;
  61   rpcprog_t sc_prog;
  62   rpcvers_t sc_vers;
  63   void (*sc_dispatch) (struct svc_req *, SVCXPRT *);
  64   bool_t sc_mapped;
  65 };
  66 #ifdef _RPC_THREAD_SAFE_
  67 #define svc_head RPC_THREAD_VARIABLE(svc_head_s)
  68 #else
  69 static struct svc_callout *svc_head;
  70 #endif
  71
  72 /* ***************  SVCXPRT related stuff **************** */
  73
  74 /* Activate a transport handle. */
  75 void
  76 xprt_register (SVCXPRT *xprt)
  77 {
  78   register int sock = xprt->xp_sock;
  79   register int i;
  80
  81   if (xports == NULL)
  82     {
  83       xports = (SVCXPRT **) malloc (_rpc_dtablesize () * sizeof (SVCXPRT *));
  84       if (xports == NULL) /* Don´t add handle */
  85         return;
  86     }
  87
  88   if (sock < _rpc_dtablesize ())
  89     {
  90       struct pollfd *new_svc_pollfd;
  91
  92       xports[sock] = xprt;
  93       if (sock < FD_SETSIZE)
  94         FD_SET (sock, &svc_fdset);
  95
  96       /* Check if we have an empty slot */
  97       for (i = 0; i < svc_max_pollfd; ++i)
  98         if (svc_pollfd[i].fd == -1)
  99           {
 100             svc_pollfd[i].fd = sock;
 101             svc_pollfd[i].events = (POLLIN | POLLPRI |
 102                                     POLLRDNORM | POLLRDBAND);
 103             return;
 104           }
 105
 106       new_svc_pollfd = (struct pollfd *) realloc (svc_pollfd,
 107                                                   sizeof (struct pollfd)
 108                                                   * (svc_max_pollfd + 1));
 109       if (new_svc_pollfd == NULL) /* Out of memory */
 110         return;
 111       svc_pollfd = new_svc_pollfd;
 112       ++svc_max_pollfd;
 113
 114       svc_pollfd[svc_max_pollfd - 1].fd = sock;
 115       svc_pollfd[svc_max_pollfd - 1].events = (POLLIN | POLLPRI |
 116                                                POLLRDNORM | POLLRDBAND);
 117     }
 118 }
 119 libc_hidden_def (xprt_register)
 120
 121 /* De-activate a transport handle. */
 122 void
 123 xprt_unregister (SVCXPRT *xprt)
 124 {
 125   register int sock = xprt->xp_sock;
 126   register int i;
 127
 128   if ((sock < _rpc_dtablesize ()) && (xports[sock] == xprt))
 129     {
 130       xports[sock] = (SVCXPRT *) 0;
 131
 132       if (sock < FD_SETSIZE)
 133         FD_CLR (sock, &svc_fdset);
 134
 135       for (i = 0; i < svc_max_pollfd; ++i)
 136         if (svc_pollfd[i].fd == sock)
 137           svc_pollfd[i].fd = -1;
 138     }
 139 }
 140 libc_hidden_def (xprt_unregister)
 141
 142
 143 /* ********************** CALLOUT list related stuff ************* */
 144
 145 /* Search the callout list for a program number, return the callout
 146    struct. */
 147 static struct svc_callout *
 148 svc_find (rpcprog_t prog, rpcvers_t vers, struct svc_callout **prev)
 149 {
 150   register struct svc_callout *s, *p;
 151
 152   p = NULL_SVC;
 153   for (s = svc_head; s != NULL_SVC; s = s->sc_next)
 154     {
 155       if ((s->sc_prog == prog) && (s->sc_vers == vers))
 156         goto done;
 157       p = s;
 158     }
 159 done:
 160   *prev = p;
 161   return s;
 162 }
 163
 164
 165 static bool_t
 166 svc_is_mapped (rpcprog_t prog, rpcvers_t vers)
 167 {
 168   struct svc_callout *prev;
 169   register struct svc_callout *s;
 170   s = svc_find (prog, vers, &prev);
 171   return s!= NULL_SVC && s->sc_mapped;
 172 }
 173
 174
 175 /* Add a service program to the callout list.
 176    The dispatch routine will be called when a rpc request for this
 177    program number comes in. */
 178 bool_t
 179 svc_register (SVCXPRT * xprt, rpcprog_t prog, rpcvers_t vers,
 180               void (*dispatch) (struct svc_req *, SVCXPRT *),
 181               rpcproc_t protocol)
 182 {
 183   struct svc_callout *prev;
 184   register struct svc_callout *s;
 185
 186   if ((s = svc_find (prog, vers, &prev)) != NULL_SVC)
 187     {
 188       if (s->sc_dispatch == dispatch)
 189         goto pmap_it;           /* he is registering another xptr */
 190       return FALSE;
 191     }
 192   s = (struct svc_callout *) mem_alloc (sizeof (struct svc_callout));
 193   if (s == (struct svc_callout *) 0)
 194     return FALSE;
 195
 196   s->sc_prog = prog;
 197   s->sc_vers = vers;
 198   s->sc_dispatch = dispatch;
 199   s->sc_next = svc_head;
 200   s->sc_mapped = FALSE;
 201   svc_head = s;
 202
 203 pmap_it:
 204   /* now register the information with the local binder service */
 205   if (protocol)
 206     {
 207       if (! pmap_set (prog, vers, protocol, xprt->xp_port))
 208         return FALSE;
 209
 210       s->sc_mapped = TRUE;
 211     }
 212
 213   return TRUE;
 214 }
 215 libc_hidden_def (svc_register)
 216
 217 /* Remove a service program from the callout list. */
 218 void
 219 svc_unregister (rpcprog_t prog, rpcvers_t vers)
 220 {
 221   struct svc_callout *prev;
 222   register struct svc_callout *s;
 223
 224   if ((s = svc_find (prog, vers, &prev)) == NULL_SVC)
 225     return;
 226
 227   if (prev == NULL_SVC)
 228     svc_head = s->sc_next;
 229   else
 230     prev->sc_next = s->sc_next;
 231
 232   s->sc_next = NULL_SVC;
 233   mem_free ((char *) s, (u_int) sizeof (struct svc_callout));
 234   /* now unregister the information with the local binder service */
 235   if (! svc_is_mapped (prog, vers))
 236     pmap_unset (prog, vers);
 237 }
 238 libc_hidden_def (svc_unregister)
 239
 240 /* ******************* REPLY GENERATION ROUTINES  ************ */
 241
 242 /* Send a reply to an rpc request */
 243 bool_t
 244 svc_sendreply (register SVCXPRT *xprt, xdrproc_t xdr_results,
 245                caddr_t xdr_location)
 246 {
 247   struct rpc_msg rply;
 248
 249   rply.rm_direction = REPLY;
 250   rply.rm_reply.rp_stat = MSG_ACCEPTED;
 251   rply.acpted_rply.ar_verf = xprt->xp_verf;
 252   rply.acpted_rply.ar_stat = SUCCESS;
 253   rply.acpted_rply.ar_results.where = xdr_location;
 254   rply.acpted_rply.ar_results.proc = xdr_results;
 255   return SVC_REPLY (xprt, &rply);
 256 }
 257 INTDEF (svc_sendreply)
 258
 259 /* No procedure error reply */
 260 void
 261 svcerr_noproc (register 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 /* Can't decode args error reply */
 273 void
 274 svcerr_decode (register SVCXPRT *xprt)
 275 {
 276   struct rpc_msg rply;
 277
 278   rply.rm_direction = REPLY;
 279   rply.rm_reply.rp_stat = MSG_ACCEPTED;
 280   rply.acpted_rply.ar_verf = xprt->xp_verf;
 281   rply.acpted_rply.ar_stat = GARBAGE_ARGS;
 282   SVC_REPLY (xprt, &rply);
 283 }
 284 INTDEF (svcerr_decode)
 285
 286 /* Some system error */
 287 void
 288 svcerr_systemerr (register SVCXPRT *xprt)
 289 {
 290   struct rpc_msg rply;
 291
 292   rply.rm_direction = REPLY;
 293   rply.rm_reply.rp_stat = MSG_ACCEPTED;
 294   rply.acpted_rply.ar_verf = xprt->xp_verf;
 295   rply.acpted_rply.ar_stat = SYSTEM_ERR;
 296   SVC_REPLY (xprt, &rply);
 297 }
 298
 299 /* Authentication error reply */
 300 void
 301 svcerr_auth (SVCXPRT *xprt, enum auth_stat why)
 302 {
 303   struct rpc_msg rply;
 304
 305   rply.rm_direction = REPLY;
 306   rply.rm_reply.rp_stat = MSG_DENIED;
 307   rply.rjcted_rply.rj_stat = AUTH_ERROR;
 308   rply.rjcted_rply.rj_why = why;
 309   SVC_REPLY (xprt, &rply);
 310 }
 311 libc_hidden_def (svcerr_auth)
 312
 313 /* Auth too weak error reply */
 314 void
 315 svcerr_weakauth (SVCXPRT *xprt)
 316 {
 317   svcerr_auth (xprt, AUTH_TOOWEAK);
 318 }
 319
 320 /* Program unavailable error reply */
 321 void
 322 svcerr_noprog (register SVCXPRT *xprt)
 323 {
 324   struct rpc_msg rply;
 325
 326   rply.rm_direction = REPLY;
 327   rply.rm_reply.rp_stat = MSG_ACCEPTED;
 328   rply.acpted_rply.ar_verf = xprt->xp_verf;
 329   rply.acpted_rply.ar_stat = PROG_UNAVAIL;
 330   SVC_REPLY (xprt, &rply);
 331 }
 332 libc_hidden_def (svcerr_noprog)
 333
 334 /* Program version mismatch error reply */
 335 void
 336 svcerr_progvers (register SVCXPRT *xprt, rpcvers_t low_vers,
 337                  rpcvers_t high_vers)
 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_MISMATCH;
 345   rply.acpted_rply.ar_vers.low = low_vers;
 346   rply.acpted_rply.ar_vers.high = high_vers;
 347   SVC_REPLY (xprt, &rply);
 348 }
 349 libc_hidden_def (svcerr_progvers)
 350
 351 /* ******************* SERVER INPUT STUFF ******************* */
 352
 353 /*
 354  * Get server side input from some transport.
 355  *
 356  * Statement of authentication parameters management:
 357  * This function owns and manages all authentication parameters, specifically
 358  * the "raw" parameters (msg.rm_call.cb_cred and msg.rm_call.cb_verf) and
 359  * the "cooked" credentials (rqst->rq_clntcred).
 360  * However, this function does not know the structure of the cooked
 361  * credentials, so it make the following assumptions:
 362  *   a) the structure is contiguous (no pointers), and
 363  *   b) the cred structure size does not exceed RQCRED_SIZE bytes.
 364  * In all events, all three parameters are freed upon exit from this routine.
 365  * The storage is trivially management on the call stack in user land, but
 366  * is mallocated in kernel land.
 367  */
 368
 369 void
 370 svc_getreq (int rdfds)
 371 {
 372   fd_set readfds;
 373
 374   FD_ZERO (&readfds);
 375   readfds.fds_bits[0] = rdfds;
 376   INTUSE(svc_getreqset) (&readfds);
 377 }
 378 INTDEF (svc_getreq)
 379
 380 void
 381 svc_getreqset (fd_set *readfds)
 382 {
 383   register fd_mask mask;
 384   register fd_mask *maskp;
 385   register int setsize;
 386   register int sock;
 387   register int bit;
 388
 389   setsize = _rpc_dtablesize ();
 390   if (setsize > FD_SETSIZE)
 391     setsize = FD_SETSIZE;
 392   maskp = readfds->fds_bits;
 393   for (sock = 0; sock < setsize; sock += NFDBITS)
 394     for (mask = *maskp++; (bit = ffsl (mask)); mask ^= (1L << (bit - 1)))
 395       INTUSE(svc_getreq_common) (sock + bit - 1);
 396 }
 397 INTDEF (svc_getreqset)
 398
 399 void
 400 svc_getreq_poll (struct pollfd *pfdp, int pollretval)
 401 {
 402   if (pollretval == 0)
 403     return;
 404
 405   register int fds_found;
 406   for (int i = fds_found = 0; i < svc_max_pollfd; ++i)
 407     {
 408       register struct pollfd *p = &pfdp[i];
 409
 410       if (p->fd != -1 && p->revents)
 411         {
 412           /* fd has input waiting */
 413           if (p->revents & POLLNVAL)
 414             xprt_unregister (xports[p->fd]);
 415           else
 416             INTUSE(svc_getreq_common) (p->fd);
 417
 418           if (++fds_found >= pollretval)
 419             break;
 420         }
 421     }
 422 }
 423 INTDEF (svc_getreq_poll)
 424
 425
 426 void
 427 svc_getreq_common (const int fd)
 428 {
 429   enum xprt_stat stat;
 430   struct rpc_msg msg;
 431   register SVCXPRT *xprt;
 432   char cred_area[2 * MAX_AUTH_BYTES + RQCRED_SIZE];
 433   msg.rm_call.cb_cred.oa_base = cred_area;
 434   msg.rm_call.cb_verf.oa_base = &(cred_area[MAX_AUTH_BYTES]);
 435
 436   xprt = xports[fd];
 437   /* Do we control fd? */
 438   if (xprt == NULL)
 439      return;
 440
 441   /* now receive msgs from xprtprt (support batch calls) */
 442   do
 443     {
 444       if (SVC_RECV (xprt, &msg))
 445         {
 446           /* now find the exported program and call it */
 447           struct svc_callout *s;
 448           struct svc_req r;
 449           enum auth_stat why;
 450           rpcvers_t low_vers;
 451           rpcvers_t high_vers;
 452           int prog_found;
 453
 454           r.rq_clntcred = &(cred_area[2 * MAX_AUTH_BYTES]);
 455           r.rq_xprt = xprt;
 456           r.rq_prog = msg.rm_call.cb_prog;
 457           r.rq_vers = msg.rm_call.cb_vers;
 458           r.rq_proc = msg.rm_call.cb_proc;
 459           r.rq_cred = msg.rm_call.cb_cred;
 460
 461           /* first authenticate the message */
 462           /* Check for null flavor and bypass these calls if possible */
 463
 464           if (msg.rm_call.cb_cred.oa_flavor == AUTH_NULL)
 465             {
 466               r.rq_xprt->xp_verf.oa_flavor = _null_auth.oa_flavor;
 467               r.rq_xprt->xp_verf.oa_length = 0;
 468             }
 469           else if ((why = INTUSE(_authenticate) (&r, &msg)) != AUTH_OK)
 470             {
 471               svcerr_auth (xprt, why);
 472               goto call_done;
 473             }
 474
 475           /* now match message with a registered service */
 476           prog_found = FALSE;
 477           low_vers = 0 - 1;
 478           high_vers = 0;
 479
 480           for (s = svc_head; s != NULL_SVC; s = s->sc_next)
 481             {
 482               if (s->sc_prog == r.rq_prog)
 483                 {
 484                   if (s->sc_vers == r.rq_vers)
 485                     {
 486                       (*s->sc_dispatch) (&r, xprt);
 487                       goto call_done;
 488                     }
 489                   /* found correct version */
 490                   prog_found = TRUE;
 491                   if (s->sc_vers < low_vers)
 492                     low_vers = s->sc_vers;
 493                   if (s->sc_vers > high_vers)
 494                     high_vers = s->sc_vers;
 495                 }
 496               /* found correct program */
 497             }
 498           /* if we got here, the program or version
 499              is not served ... */
 500           if (prog_found)
 501             svcerr_progvers (xprt, low_vers, high_vers);
 502           else
 503             svcerr_noprog (xprt);
 504           /* Fall through to ... */
 505         }
 506     call_done:
 507       if ((stat = SVC_STAT (xprt)) == XPRT_DIED)
 508         {
 509           SVC_DESTROY (xprt);
 510           break;
 511         }
 512     }
 513   while (stat == XPRT_MOREREQS);
 514 }
 515 INTDEF (svc_getreq_common)
 516
 517 #ifdef _RPC_THREAD_SAFE_
 518
 519 void
 520 __rpc_thread_svc_cleanup (void)
 521 {
 522   struct svc_callout *svcp;
 523
 524   while ((svcp = svc_head) != NULL)
 525     svc_unregister (svcp->sc_prog, svcp->sc_vers);
 526 }
 527
 528 #endif /* _RPC_THREAD_SAFE_ */