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 ((SVCXPRT **)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 ((struct svc_callout *)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
 119 /* De-activate a transport handle. */
 120 void
 121 xprt_unregister (SVCXPRT *xprt)
 122 {
 123   register int sock = xprt->xp_sock;
 124   register int i;
 125
 126   if ((sock < _rpc_dtablesize ()) && (xports[sock] == xprt))
 127     {
 128       xports[sock] = (SVCXPRT *) 0;
 129
 130       if (sock < FD_SETSIZE)
 131         FD_CLR (sock, &svc_fdset);
 132
 133       for (i = 0; i < svc_max_pollfd; ++i)
 134         if (svc_pollfd[i].fd == sock)
 135           svc_pollfd[i].fd = -1;
 136     }
 137 }
 138
 139
 140 /* ********************** CALLOUT list related stuff ************* */
 141
 142 /* Search the callout list for a program number, return the callout
 143    struct. */
 144 static struct svc_callout *
 145 svc_find (rpcprog_t prog, rpcvers_t vers, struct svc_callout **prev)
 146 {
 147   register struct svc_callout *s, *p;
 148
 149   p = NULL_SVC;
 150   for (s = svc_head; s != NULL_SVC; s = s->sc_next)
 151     {
 152       if ((s->sc_prog == prog) && (s->sc_vers == vers))
 153         goto done;
 154       p = s;
 155     }
 156 done:
 157   *prev = p;
 158   return s;
 159 }
 160
 161 /* Add a service program to the callout list.
 162    The dispatch routine will be called when a rpc request for this
 163    program number comes in. */
 164 bool_t
 165 svc_register (SVCXPRT * xprt, rpcprog_t prog, rpcvers_t vers,
 166               void (*dispatch) (struct svc_req *, SVCXPRT *),
 167               rpcproc_t 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     {
 174       if (s->sc_dispatch == dispatch)
 175         goto pmap_it;           /* he is registering another xptr */
 176       return FALSE;
 177     }
 178   s = (struct svc_callout *) mem_alloc (sizeof (struct svc_callout));
 179   if (s == (struct svc_callout *) 0)
 180     return FALSE;
 181
 182   s->sc_prog = prog;
 183   s->sc_vers = vers;
 184   s->sc_dispatch = dispatch;
 185   s->sc_next = svc_head;
 186   svc_head = s;
 187
 188 pmap_it:
 189   /* now register the information with the local binder service */
 190   if (protocol)
 191     return pmap_set (prog, vers, protocol, xprt->xp_port);
 192
 193   return TRUE;
 194 }
 195 INTDEF (svc_register)
 196
 197 /* Remove a service program from the callout list. */
 198 void
 199 svc_unregister (rpcprog_t prog, rpcvers_t vers)
 200 {
 201   struct svc_callout *prev;
 202   register struct svc_callout *s;
 203
 204   if ((s = svc_find (prog, vers, &prev)) == NULL_SVC)
 205     return;
 206
 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   pmap_unset (prog, vers);
 216 }
 217 INTDEF (svc_unregister)
 218
 219 /* ******************* REPLY GENERATION ROUTINES  ************ */
 220
 221 /* Send a reply to an rpc request */
 222 bool_t
 223 svc_sendreply (register SVCXPRT *xprt, xdrproc_t xdr_results,
 224                caddr_t xdr_location)
 225 {
 226   struct rpc_msg rply;
 227
 228   rply.rm_direction = REPLY;
 229   rply.rm_reply.rp_stat = MSG_ACCEPTED;
 230   rply.acpted_rply.ar_verf = xprt->xp_verf;
 231   rply.acpted_rply.ar_stat = SUCCESS;
 232   rply.acpted_rply.ar_results.where = xdr_location;
 233   rply.acpted_rply.ar_results.proc = xdr_results;
 234   return SVC_REPLY (xprt, &rply);
 235 }
 236 INTDEF (svc_sendreply)
 237
 238 /* No procedure error reply */
 239 void
 240 svcerr_noproc (register SVCXPRT *xprt)
 241 {
 242   struct rpc_msg rply;
 243
 244   rply.rm_direction = REPLY;
 245   rply.rm_reply.rp_stat = MSG_ACCEPTED;
 246   rply.acpted_rply.ar_verf = xprt->xp_verf;
 247   rply.acpted_rply.ar_stat = PROC_UNAVAIL;
 248   SVC_REPLY (xprt, &rply);
 249 }
 250
 251 /* Can't decode args error reply */
 252 void
 253 svcerr_decode (register SVCXPRT *xprt)
 254 {
 255   struct rpc_msg rply;
 256
 257   rply.rm_direction = REPLY;
 258   rply.rm_reply.rp_stat = MSG_ACCEPTED;
 259   rply.acpted_rply.ar_verf = xprt->xp_verf;
 260   rply.acpted_rply.ar_stat = GARBAGE_ARGS;
 261   SVC_REPLY (xprt, &rply);
 262 }
 263 INTDEF (svcerr_decode)
 264
 265 /* Some system error */
 266 void
 267 svcerr_systemerr (register SVCXPRT *xprt)
 268 {
 269   struct rpc_msg rply;
 270
 271   rply.rm_direction = REPLY;
 272   rply.rm_reply.rp_stat = MSG_ACCEPTED;
 273   rply.acpted_rply.ar_verf = xprt->xp_verf;
 274   rply.acpted_rply.ar_stat = SYSTEM_ERR;
 275   SVC_REPLY (xprt, &rply);
 276 }
 277
 278 /* Authentication error reply */
 279 void
 280 svcerr_auth (SVCXPRT *xprt, enum auth_stat why)
 281 {
 282   struct rpc_msg rply;
 283
 284   rply.rm_direction = REPLY;
 285   rply.rm_reply.rp_stat = MSG_DENIED;
 286   rply.rjcted_rply.rj_stat = AUTH_ERROR;
 287   rply.rjcted_rply.rj_why = why;
 288   SVC_REPLY (xprt, &rply);
 289 }
 290
 291 /* Auth too weak error reply */
 292 void
 293 svcerr_weakauth (SVCXPRT *xprt)
 294 {
 295   svcerr_auth (xprt, AUTH_TOOWEAK);
 296 }
 297
 298 /* Program unavailable error reply */
 299 void
 300 svcerr_noprog (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 = PROG_UNAVAIL;
 308   SVC_REPLY (xprt, &rply);
 309 }
 310
 311 /* Program version mismatch error reply */
 312 void
 313 svcerr_progvers (register SVCXPRT *xprt, rpcvers_t low_vers,
 314                  rpcvers_t high_vers)
 315 {
 316   struct rpc_msg rply;
 317
 318   rply.rm_direction = REPLY;
 319   rply.rm_reply.rp_stat = MSG_ACCEPTED;
 320   rply.acpted_rply.ar_verf = xprt->xp_verf;
 321   rply.acpted_rply.ar_stat = PROG_MISMATCH;
 322   rply.acpted_rply.ar_vers.low = low_vers;
 323   rply.acpted_rply.ar_vers.high = high_vers;
 324   SVC_REPLY (xprt, &rply);
 325 }
 326
 327 /* ******************* SERVER INPUT STUFF ******************* */
 328
 329 /*
 330  * Get server side input from some transport.
 331  *
 332  * Statement of authentication parameters management:
 333  * This function owns and manages all authentication parameters, specifically
 334  * the "raw" parameters (msg.rm_call.cb_cred and msg.rm_call.cb_verf) and
 335  * the "cooked" credentials (rqst->rq_clntcred).
 336  * However, this function does not know the structure of the cooked
 337  * credentials, so it make the following assumptions:
 338  *   a) the structure is contiguous (no pointers), and
 339  *   b) the cred structure size does not exceed RQCRED_SIZE bytes.
 340  * In all events, all three parameters are freed upon exit from this routine.
 341  * The storage is trivially management on the call stack in user land, but
 342  * is mallocated in kernel land.
 343  */
 344
 345 void
 346 svc_getreq (int rdfds)
 347 {
 348   fd_set readfds;
 349
 350   FD_ZERO (&readfds);
 351   readfds.fds_bits[0] = rdfds;
 352   INTUSE(svc_getreqset) (&readfds);
 353 }
 354 INTDEF (svc_getreq)
 355
 356 void
 357 svc_getreqset (fd_set *readfds)
 358 {
 359   register u_int32_t mask;
 360   register u_int32_t *maskp;
 361   register int setsize;
 362   register int sock;
 363   register int bit;
 364
 365   setsize = _rpc_dtablesize ();
 366   maskp = (u_int32_t *) readfds->fds_bits;
 367   for (sock = 0; sock < setsize; sock += 32)
 368     for (mask = *maskp++; (bit = ffs (mask)); mask ^= (1 << (bit - 1)))
 369       INTUSE(svc_getreq_common) (sock + bit - 1);
 370 }
 371 INTDEF (svc_getreqset)
 372
 373 void
 374 svc_getreq_poll (struct pollfd *pfdp, int pollretval)
 375 {
 376   register int i;
 377   register int fds_found;
 378
 379   for (i = fds_found = 0; i < svc_max_pollfd && fds_found < pollretval; ++i)
 380     {
 381       register struct pollfd *p = &pfdp[i];
 382
 383       if (p->fd != -1 && p->revents)
 384         {
 385           /* fd has input waiting */
 386           ++fds_found;
 387
 388           if (p->revents & POLLNVAL)
 389             xprt_unregister (xports[p->fd]);
 390           else
 391             INTUSE(svc_getreq_common) (p->fd);
 392         }
 393     }
 394 }
 395 INTDEF (svc_getreq_poll)
 396
 397
 398 void
 399 svc_getreq_common (const int fd)
 400 {
 401   enum xprt_stat stat;
 402   struct rpc_msg msg;
 403   register SVCXPRT *xprt;
 404   char cred_area[2 * MAX_AUTH_BYTES + RQCRED_SIZE];
 405   msg.rm_call.cb_cred.oa_base = cred_area;
 406   msg.rm_call.cb_verf.oa_base = &(cred_area[MAX_AUTH_BYTES]);
 407
 408   xprt = xports[fd];
 409   /* Do we control fd? */
 410   if (xprt == NULL)
 411      return;
 412
 413   /* now receive msgs from xprtprt (support batch calls) */
 414   do
 415     {
 416       if (SVC_RECV (xprt, &msg))
 417         {
 418           /* now find the exported program and call it */
 419           struct svc_callout *s;
 420           struct svc_req r;
 421           enum auth_stat why;
 422           rpcvers_t low_vers;
 423           rpcvers_t high_vers;
 424           int prog_found;
 425
 426           r.rq_clntcred = &(cred_area[2 * MAX_AUTH_BYTES]);
 427           r.rq_xprt = xprt;
 428           r.rq_prog = msg.rm_call.cb_prog;
 429           r.rq_vers = msg.rm_call.cb_vers;
 430           r.rq_proc = msg.rm_call.cb_proc;
 431           r.rq_cred = msg.rm_call.cb_cred;
 432
 433           /* first authenticate the message */
 434           /* Check for null flavor and bypass these calls if possible */
 435
 436           if (msg.rm_call.cb_cred.oa_flavor == AUTH_NULL)
 437             {
 438               r.rq_xprt->xp_verf.oa_flavor = _null_auth.oa_flavor;
 439               r.rq_xprt->xp_verf.oa_length = 0;
 440             }
 441           else if ((why = INTUSE(_authenticate) (&r, &msg)) != AUTH_OK)
 442             {
 443               svcerr_auth (xprt, why);
 444               goto call_done;
 445             }
 446
 447           /* now match message with a registered service */
 448           prog_found = FALSE;
 449           low_vers = 0 - 1;
 450           high_vers = 0;
 451
 452           for (s = svc_head; s != NULL_SVC; s = s->sc_next)
 453             {
 454               if (s->sc_prog == r.rq_prog)
 455                 {
 456                   if (s->sc_vers == r.rq_vers)
 457                     {
 458                       (*s->sc_dispatch) (&r, xprt);
 459                       goto call_done;
 460                     }
 461                   /* found correct version */
 462                   prog_found = TRUE;
 463                   if (s->sc_vers < low_vers)
 464                     low_vers = s->sc_vers;
 465                   if (s->sc_vers > high_vers)
 466                     high_vers = s->sc_vers;
 467                 }
 468               /* found correct program */
 469             }
 470           /* if we got here, the program or version
 471              is not served ... */
 472           if (prog_found)
 473             svcerr_progvers (xprt, low_vers, high_vers);
 474           else
 475             svcerr_noprog (xprt);
 476           /* Fall through to ... */
 477         }
 478     call_done:
 479       if ((stat = SVC_STAT (xprt)) == XPRT_DIED)
 480         {
 481           SVC_DESTROY (xprt);
 482           break;
 483         }
 484     }
 485   while (stat == XPRT_MOREREQS);
 486 }
 487 INTDEF (svc_getreq_common)
 488
 489 #ifdef _RPC_THREAD_SAFE_
 490
 491 void
 492 __rpc_thread_svc_cleanup (void)
 493 {
 494   struct svc_callout *svcp;
 495
 496   while ((svcp = svc_head) != NULL)
 497     svc_unregister (svcp->sc_prog, svcp->sc_vers);
 498 }
 499
 500 #endif /* _RPC_THREAD_SAFE_ */