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 };
  65 #ifdef _RPC_THREAD_SAFE_
  66 #define svc_head RPC_THREAD_VARIABLE(svc_head_s)
  67 #else
  68 static struct svc_callout *svc_head;
  69 #endif
  70
  71 /* ***************  SVCXPRT related stuff **************** */
  72
  73 /* Activate a transport handle. */
  74 void
  75 xprt_register (SVCXPRT *xprt)
  76 {
  77   register int sock = xprt->xp_sock;
  78   register int i;
  79
  80   if (xports == NULL)
  81     {
  82       xports = (SVCXPRT **) malloc (_rpc_dtablesize () * sizeof (SVCXPRT *));
  83       if (xports == NULL) /* Don´t add handle */
  84         return;
  85     }
  86
  87   if (sock < _rpc_dtablesize ())
  88     {
  89       struct pollfd *new_svc_pollfd;
  90
  91       xports[sock] = xprt;
  92       if (sock < FD_SETSIZE)
  93         FD_SET (sock, &svc_fdset);
  94
  95       /* Check if we have an empty slot */
  96       for (i = 0; i < svc_max_pollfd; ++i)
  97         if (svc_pollfd[i].fd == -1)
  98           {
  99             svc_pollfd[i].fd = sock;
 100             svc_pollfd[i].events = (POLLIN | POLLPRI |
 101                                     POLLRDNORM | POLLRDBAND);
 102             return;
 103           }
 104
 105       new_svc_pollfd = (struct pollfd *) realloc (svc_pollfd,
 106                                                   sizeof (struct pollfd)
 107                                                   * (svc_max_pollfd + 1));
 108       if (new_svc_pollfd == NULL) /* Out of memory */
 109         return;
 110       svc_pollfd = new_svc_pollfd;
 111       ++svc_max_pollfd;
 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 }
 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 }
 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
 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 }
 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 }
 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 }
 238 INTDEF (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
 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 }
 265 INTDEF (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
 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 }
 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
 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 }
 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 }
 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 (int rdfds)
 352 {
 353   fd_set readfds;
 354
 355   FD_ZERO (&readfds);
 356   readfds.fds_bits[0] = rdfds;
 357   INTUSE(svc_getreqset) (&readfds);
 358 }
 359 INTDEF (svc_getreq)
 360
 361 void
 362 svc_getreqset (fd_set *readfds)
 363 {
 364   register fd_mask mask;
 365   register fd_mask *maskp;
 366   register int setsize;
 367   register int sock;
 368   register int bit;
 369
 370   setsize = _rpc_dtablesize ();
 371   if (setsize > FD_SETSIZE)
 372     setsize = FD_SETSIZE;
 373   maskp = readfds->fds_bits;
 374   for (sock = 0; sock < setsize; sock += NFDBITS)
 375     for (mask = *maskp++; (bit = ffsl (mask)); mask ^= (1L << (bit - 1)))
 376       INTUSE(svc_getreq_common) (sock + bit - 1);
 377 }
 378 INTDEF (svc_getreqset)
 379
 380 void
 381 svc_getreq_poll (struct pollfd *pfdp, int pollretval)
 382 {
 383   if (pollretval == 0)
 384     return;
 385
 386   register int fds_found;
 387   for (int i = fds_found = 0; i < svc_max_pollfd; ++i)
 388     {
 389       register struct pollfd *p = &pfdp[i];
 390
 391       if (p->fd != -1 && p->revents)
 392         {
 393           /* fd has input waiting */
 394           if (p->revents & POLLNVAL)
 395             xprt_unregister (xports[p->fd]);
 396           else
 397             INTUSE(svc_getreq_common) (p->fd);
 398
 399           if (++fds_found >= pollretval)
 400             break;
 401         }
 402     }
 403 }
 404 INTDEF (svc_getreq_poll)
 405
 406
 407 void
 408 svc_getreq_common (const int fd)
 409 {
 410   enum xprt_stat stat;
 411   struct rpc_msg msg;
 412   register SVCXPRT *xprt;
 413   char cred_area[2 * MAX_AUTH_BYTES + RQCRED_SIZE];
 414   msg.rm_call.cb_cred.oa_base = cred_area;
 415   msg.rm_call.cb_verf.oa_base = &(cred_area[MAX_AUTH_BYTES]);
 416
 417   xprt = xports[fd];
 418   /* Do we control fd? */
 419   if (xprt == NULL)
 420      return;
 421
 422   /* now receive msgs from xprtprt (support batch calls) */
 423   do
 424     {
 425       if (SVC_RECV (xprt, &msg))
 426         {
 427           /* now find the exported program and call it */
 428           struct svc_callout *s;
 429           struct svc_req r;
 430           enum auth_stat why;
 431           rpcvers_t low_vers;
 432           rpcvers_t high_vers;
 433           int prog_found;
 434
 435           r.rq_clntcred = &(cred_area[2 * MAX_AUTH_BYTES]);
 436           r.rq_xprt = xprt;
 437           r.rq_prog = msg.rm_call.cb_prog;
 438           r.rq_vers = msg.rm_call.cb_vers;
 439           r.rq_proc = msg.rm_call.cb_proc;
 440           r.rq_cred = msg.rm_call.cb_cred;
 441
 442           /* first authenticate the message */
 443           /* Check for null flavor and bypass these calls if possible */
 444
 445           if (msg.rm_call.cb_cred.oa_flavor == AUTH_NULL)
 446             {
 447               r.rq_xprt->xp_verf.oa_flavor = _null_auth.oa_flavor;
 448               r.rq_xprt->xp_verf.oa_length = 0;
 449             }
 450           else if ((why = INTUSE(_authenticate) (&r, &msg)) != AUTH_OK)
 451             {
 452               svcerr_auth (xprt, why);
 453               goto call_done;
 454             }
 455
 456           /* now match message with a registered service */
 457           prog_found = FALSE;
 458           low_vers = 0 - 1;
 459           high_vers = 0;
 460
 461           for (s = svc_head; s != NULL_SVC; s = s->sc_next)
 462             {
 463               if (s->sc_prog == r.rq_prog)
 464                 {
 465                   if (s->sc_vers == r.rq_vers)
 466                     {
 467                       (*s->sc_dispatch) (&r, xprt);
 468                       goto call_done;
 469                     }
 470                   /* found correct version */
 471                   prog_found = TRUE;
 472                   if (s->sc_vers < low_vers)
 473                     low_vers = s->sc_vers;
 474                   if (s->sc_vers > high_vers)
 475                     high_vers = s->sc_vers;
 476                 }
 477               /* found correct program */
 478             }
 479           /* if we got here, the program or version
 480              is not served ... */
 481           if (prog_found)
 482             svcerr_progvers (xprt, low_vers, high_vers);
 483           else
 484             svcerr_noprog (xprt);
 485           /* Fall through to ... */
 486         }
 487     call_done:
 488       if ((stat = SVC_STAT (xprt)) == XPRT_DIED)
 489         {
 490           SVC_DESTROY (xprt);
 491           break;
 492         }
 493     }
 494   while (stat == XPRT_MOREREQS);
 495 }
 496 INTDEF (svc_getreq_common)
 497
 498 #ifdef _RPC_THREAD_SAFE_
 499
 500 void
 501 __rpc_thread_svc_cleanup (void)
 502 {
 503   struct svc_callout *svcp;
 504
 505   while ((svcp = svc_head) != NULL)
 506     svc_unregister (svcp->sc_prog, svcp->sc_vers);
 507 }
 508
 509 #endif /* _RPC_THREAD_SAFE_ */