sunrpc/clnt_udp.c

   1 /* @(#)clnt_udp.c       2.2 88/08/01 4.0 RPCSRC */
   2 /*
   3  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
   4  * unrestricted use provided that this legend is included on all tape
   5  * media and as a part of the software program in whole or part.  Users
   6  * may copy or modify Sun RPC without charge, but are not authorized
   7  * to license or distribute it to anyone else except as part of a product or
   8  * program developed by the user.
   9  *
  10  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
  11  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
  12  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
  13  *
  14  * Sun RPC is provided with no support and without any obligation on the
  15  * part of Sun Microsystems, Inc. to assist in its use, correction,
  16  * modification or enhancement.
  17  *
  18  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
  19  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
  20  * OR ANY PART THEREOF.
  21  *
  22  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
  23  * or profits or other special, indirect and consequential damages, even if
  24  * Sun has been advised of the possibility of such damages.
  25  *
  26  * Sun Microsystems, Inc.
  27  * 2550 Garcia Avenue
  28  * Mountain View, California  94043
  29  */
  30 #if !defined(lint) && defined(SCCSIDS)
  31 static char sccsid[] = "@(#)clnt_udp.c 1.39 87/08/11 Copyr 1984 Sun Micro";
  32 #endif
  33
  34 /*
  35  * clnt_udp.c, Implements a UDP/IP based, client side RPC.
  36  *
  37  * Copyright (C) 1984, Sun Microsystems, Inc.
  38  */
  39
  40 #include <stdio.h>
  41 #include <unistd.h>
  42 #include <rpc/rpc.h>
  43 #include <rpc/xdr.h>
  44 #include <rpc/clnt.h>
  45 #include <sys/poll.h>
  46 #include <sys/socket.h>
  47 #include <sys/ioctl.h>
  48 #include <netdb.h>
  49 #include <errno.h>
  50 #include <rpc/pmap_clnt.h>
  51
  52 extern bool_t xdr_opaque_auth (XDR *, struct opaque_auth *);
  53
  54 /*
  55  * UDP bases client side rpc operations
  56  */
  57 static enum clnt_stat clntudp_call (CLIENT *, u_long, xdrproc_t, caddr_t,
  58                                     xdrproc_t, caddr_t, struct timeval);
  59 static void clntudp_abort (void);
  60 static void clntudp_geterr (CLIENT *, struct rpc_err *);
  61 static bool_t clntudp_freeres (CLIENT *, xdrproc_t, caddr_t);
  62 static bool_t clntudp_control (CLIENT *, int, char *);
  63 static void clntudp_destroy (CLIENT *);
  64
  65 static struct clnt_ops udp_ops =
  66 {
  67   clntudp_call,
  68   clntudp_abort,
  69   clntudp_geterr,
  70   clntudp_freeres,
  71   clntudp_destroy,
  72   clntudp_control
  73 };
  74
  75 /*
  76  * Private data kept per client handle
  77  */
  78 struct cu_data
  79   {
  80     int cu_sock;
  81     bool_t cu_closeit;
  82     struct sockaddr_in cu_raddr;
  83     int cu_rlen;
  84     struct timeval cu_wait;
  85     struct timeval cu_total;
  86     struct rpc_err cu_error;
  87     XDR cu_outxdrs;
  88     u_int cu_xdrpos;
  89     u_int cu_sendsz;
  90     char *cu_outbuf;
  91     u_int cu_recvsz;
  92     char cu_inbuf[1];
  93   };
  94
  95 /*
  96  * Create a UDP based client handle.
  97  * If *sockp<0, *sockp is set to a newly created UPD socket.
  98  * If raddr->sin_port is 0 a binder on the remote machine
  99  * is consulted for the correct port number.
 100  * NB: It is the clients responsibility to close *sockp.
 101  * NB: The rpch->cl_auth is initialized to null authentication.
 102  *     Caller may wish to set this something more useful.
 103  *
 104  * wait is the amount of time used between retransmitting a call if
 105  * no response has been heard; retransmission occurs until the actual
 106  * rpc call times out.
 107  *
 108  * sendsz and recvsz are the maximum allowable packet sizes that can be
 109  * sent and received.
 110  */
 111 CLIENT *
 112 clntudp_bufcreate (raddr, program, version, wait, sockp, sendsz, recvsz)
 113      struct sockaddr_in *raddr;
 114      u_long program;
 115      u_long version;
 116      struct timeval wait;
 117      int *sockp;
 118      u_int sendsz;
 119      u_int recvsz;
 120 {
 121   CLIENT *cl;
 122   struct cu_data *cu = NULL;
 123   struct timeval now;
 124   struct rpc_msg call_msg;
 125
 126   cl = (CLIENT *) mem_alloc (sizeof (CLIENT));
 127   if (cl == NULL)
 128     {
 129       (void) fprintf (stderr, _("clntudp_create: out of memory\n"));
 130       rpc_createerr.cf_stat = RPC_SYSTEMERROR;
 131       rpc_createerr.cf_error.re_errno = errno;
 132       goto fooy;
 133     }
 134   sendsz = ((sendsz + 3) / 4) * 4;
 135   recvsz = ((recvsz + 3) / 4) * 4;
 136   cu = (struct cu_data *) mem_alloc (sizeof (*cu) + sendsz + recvsz);
 137   if (cu == NULL)
 138     {
 139       (void) fprintf (stderr, _("clntudp_create: out of memory\n"));
 140       rpc_createerr.cf_stat = RPC_SYSTEMERROR;
 141       rpc_createerr.cf_error.re_errno = errno;
 142       goto fooy;
 143     }
 144   cu->cu_outbuf = &cu->cu_inbuf[recvsz];
 145
 146   (void) gettimeofday (&now, (struct timezone *) 0);
 147   if (raddr->sin_port == 0)
 148     {
 149       u_short port;
 150       if ((port =
 151            pmap_getport (raddr, program, version, IPPROTO_UDP)) == 0)
 152         {
 153           goto fooy;
 154         }
 155       raddr->sin_port = htons (port);
 156     }
 157   cl->cl_ops = &udp_ops;
 158   cl->cl_private = (caddr_t) cu;
 159   cu->cu_raddr = *raddr;
 160   cu->cu_rlen = sizeof (cu->cu_raddr);
 161   cu->cu_wait = wait;
 162   cu->cu_total.tv_sec = -1;
 163   cu->cu_total.tv_usec = -1;
 164   cu->cu_sendsz = sendsz;
 165   cu->cu_recvsz = recvsz;
 166   call_msg.rm_xid = getpid () ^ now.tv_sec ^ now.tv_usec;
 167   call_msg.rm_direction = CALL;
 168   call_msg.rm_call.cb_rpcvers = RPC_MSG_VERSION;
 169   call_msg.rm_call.cb_prog = program;
 170   call_msg.rm_call.cb_vers = version;
 171   xdrmem_create (&(cu->cu_outxdrs), cu->cu_outbuf,
 172                  sendsz, XDR_ENCODE);
 173   if (!xdr_callhdr (&(cu->cu_outxdrs), &call_msg))
 174     {
 175       goto fooy;
 176     }
 177   cu->cu_xdrpos = XDR_GETPOS (&(cu->cu_outxdrs));
 178   if (*sockp < 0)
 179     {
 180       int dontblock = 1;
 181
 182       *sockp = socket (AF_INET, SOCK_DGRAM, IPPROTO_UDP);
 183       if (*sockp < 0)
 184         {
 185           rpc_createerr.cf_stat = RPC_SYSTEMERROR;
 186           rpc_createerr.cf_error.re_errno = errno;
 187           goto fooy;
 188         }
 189       /* attempt to bind to prov port */
 190       (void) bindresvport (*sockp, (struct sockaddr_in *) 0);
 191       /* the sockets rpc controls are non-blocking */
 192       (void) ioctl (*sockp, FIONBIO, (char *) &dontblock);
 193       cu->cu_closeit = TRUE;
 194     }
 195   else
 196     {
 197       cu->cu_closeit = FALSE;
 198     }
 199   cu->cu_sock = *sockp;
 200   cl->cl_auth = authnone_create ();
 201   return cl;
 202 fooy:
 203   if (cu)
 204     mem_free ((caddr_t) cu, sizeof (*cu) + sendsz + recvsz);
 205   if (cl)
 206     mem_free ((caddr_t) cl, sizeof (CLIENT));
 207   return (CLIENT *) NULL;
 208 }
 209
 210 CLIENT *
 211 clntudp_create (raddr, program, version, wait, sockp)
 212      struct sockaddr_in *raddr;
 213      u_long program;
 214      u_long version;
 215      struct timeval wait;
 216      int *sockp;
 217 {
 218
 219   return clntudp_bufcreate (raddr, program, version, wait, sockp,
 220                             UDPMSGSIZE, UDPMSGSIZE);
 221 }
 222
 223 static enum clnt_stat
 224 clntudp_call (cl, proc, xargs, argsp, xresults, resultsp, utimeout)
 225      CLIENT *cl;        /* client handle */
 226      u_long proc;               /* procedure number */
 227      xdrproc_t xargs;           /* xdr routine for args */
 228      caddr_t argsp;             /* pointer to args */
 229      xdrproc_t xresults;        /* xdr routine for results */
 230      caddr_t resultsp;          /* pointer to results */
 231      struct timeval utimeout;   /* seconds to wait before giving up */
 232 {
 233   struct cu_data *cu = (struct cu_data *) cl->cl_private;
 234   XDR *xdrs;
 235   int outlen = 0;
 236   int inlen;
 237   socklen_t fromlen;
 238   struct pollfd fd;
 239   int milliseconds = (cu->cu_wait.tv_sec * 1000) +
 240     (cu->cu_wait.tv_usec / 1000);
 241   struct sockaddr_in from;
 242   struct rpc_msg reply_msg;
 243   XDR reply_xdrs;
 244   struct timeval time_waited;
 245   bool_t ok;
 246   int nrefreshes = 2;           /* number of times to refresh cred */
 247   struct timeval timeout;
 248
 249   if (cu->cu_total.tv_usec == -1)
 250     {
 251       timeout = utimeout;       /* use supplied timeout */
 252     }
 253   else
 254     {
 255       timeout = cu->cu_total;   /* use default timeout */
 256     }
 257
 258   time_waited.tv_sec = 0;
 259   time_waited.tv_usec = 0;
 260 call_again:
 261   xdrs = &(cu->cu_outxdrs);
 262   if (xargs == NULL)
 263     goto get_reply;
 264   xdrs->x_op = XDR_ENCODE;
 265   XDR_SETPOS (xdrs, cu->cu_xdrpos);
 266   /*
 267    * the transaction is the first thing in the out buffer
 268    */
 269   (*(u_short *) (cu->cu_outbuf))++;
 270   if ((!XDR_PUTLONG (xdrs, (long *) &proc)) ||
 271       (!AUTH_MARSHALL (cl->cl_auth, xdrs)) ||
 272       (!(*xargs) (xdrs, argsp)))
 273     return (cu->cu_error.re_status = RPC_CANTENCODEARGS);
 274   outlen = (int) XDR_GETPOS (xdrs);
 275
 276 send_again:
 277   if (sendto (cu->cu_sock, cu->cu_outbuf, outlen, 0,
 278               (struct sockaddr *) &(cu->cu_raddr), cu->cu_rlen)
 279       != outlen)
 280     {
 281       cu->cu_error.re_errno = errno;
 282       return (cu->cu_error.re_status = RPC_CANTSEND);
 283     }
 284
 285   /*
 286    * Hack to provide rpc-based message passing
 287    */
 288   if (timeout.tv_sec == 0 && timeout.tv_usec == 0)
 289     {
 290       return (cu->cu_error.re_status = RPC_TIMEDOUT);
 291     }
 292  get_reply:
 293   /*
 294    * sub-optimal code appears here because we have
 295    * some clock time to spare while the packets are in flight.
 296    * (We assume that this is actually only executed once.)
 297    */
 298   reply_msg.acpted_rply.ar_verf = _null_auth;
 299   reply_msg.acpted_rply.ar_results.where = resultsp;
 300   reply_msg.acpted_rply.ar_results.proc = xresults;
 301   fd.fd = cu->cu_sock;
 302   fd.events = POLLIN;
 303   for (;;)
 304     {
 305       switch (__poll(&fd, 1, milliseconds))
 306         {
 307
 308         case 0:
 309           time_waited.tv_sec += cu->cu_wait.tv_sec;
 310           time_waited.tv_usec += cu->cu_wait.tv_usec;
 311           while (time_waited.tv_usec >= 1000000)
 312             {
 313               time_waited.tv_sec++;
 314               time_waited.tv_usec -= 1000000;
 315             }
 316           if ((time_waited.tv_sec < timeout.tv_sec) ||
 317               ((time_waited.tv_sec == timeout.tv_sec) &&
 318                (time_waited.tv_usec < timeout.tv_usec)))
 319             goto send_again;
 320           return (cu->cu_error.re_status = RPC_TIMEDOUT);
 321
 322           /*
 323            * buggy in other cases because time_waited is not being
 324            * updated.
 325            */
 326         case -1:
 327           if (errno == EINTR)
 328             continue;
 329           cu->cu_error.re_errno = errno;
 330           return (cu->cu_error.re_status = RPC_CANTRECV);
 331         }
 332       do
 333         {
 334           fromlen = sizeof (struct sockaddr);
 335           inlen = recvfrom (cu->cu_sock, cu->cu_inbuf,
 336                             (int) cu->cu_recvsz, 0,
 337                             (struct sockaddr *) &from, &fromlen);
 338         }
 339       while (inlen < 0 && errno == EINTR);
 340       if (inlen < 0)
 341         {
 342           if (errno == EWOULDBLOCK)
 343             continue;
 344           cu->cu_error.re_errno = errno;
 345           return (cu->cu_error.re_status = RPC_CANTRECV);
 346         }
 347       if (inlen < 4)
 348         continue;
 349
 350       /* see if reply transaction id matches sent id.
 351         Don't do this if we only wait for a replay */
 352       if (xargs != NULL
 353           && (*((u_int32_t *) (cu->cu_inbuf))
 354               != *((u_int32_t *) (cu->cu_outbuf))))
 355         continue;
 356       /* we now assume we have the proper reply */
 357       break;
 358     }
 359
 360   /*
 361    * now decode and validate the response
 362    */
 363   xdrmem_create (&reply_xdrs, cu->cu_inbuf, (u_int) inlen, XDR_DECODE);
 364   ok = xdr_replymsg (&reply_xdrs, &reply_msg);
 365   /* XDR_DESTROY(&reply_xdrs);  save a few cycles on noop destroy */
 366   if (ok)
 367     {
 368       _seterr_reply (&reply_msg, &(cu->cu_error));
 369       if (cu->cu_error.re_status == RPC_SUCCESS)
 370         {
 371           if (!AUTH_VALIDATE (cl->cl_auth,
 372                               &reply_msg.acpted_rply.ar_verf))
 373             {
 374               cu->cu_error.re_status = RPC_AUTHERROR;
 375               cu->cu_error.re_why = AUTH_INVALIDRESP;
 376             }
 377           if (reply_msg.acpted_rply.ar_verf.oa_base != NULL)
 378             {
 379               xdrs->x_op = XDR_FREE;
 380               (void) xdr_opaque_auth (xdrs,
 381                                       &(reply_msg.acpted_rply.ar_verf));
 382             }
 383         }                       /* end successful completion */
 384       else
 385         {
 386           /* maybe our credentials need to be refreshed ... */
 387           if (nrefreshes > 0 && AUTH_REFRESH (cl->cl_auth))
 388             {
 389               nrefreshes--;
 390               goto call_again;
 391             }
 392         }                       /* end of unsuccessful completion */
 393     }                           /* end of valid reply message */
 394   else
 395     {
 396       cu->cu_error.re_status = RPC_CANTDECODERES;
 397     }
 398   return cu->cu_error.re_status;
 399 }
 400
 401 static void
 402 clntudp_geterr (CLIENT *cl, struct rpc_err *errp)
 403 {
 404   struct cu_data *cu = (struct cu_data *) cl->cl_private;
 405
 406   *errp = cu->cu_error;
 407 }
 408
 409
 410 static bool_t
 411 clntudp_freeres (CLIENT *cl, xdrproc_t xdr_res, caddr_t res_ptr)
 412 {
 413   struct cu_data *cu = (struct cu_data *) cl->cl_private;
 414   XDR *xdrs = &(cu->cu_outxdrs);
 415
 416   xdrs->x_op = XDR_FREE;
 417   return (*xdr_res) (xdrs, res_ptr);
 418 }
 419
 420 static void
 421 clntudp_abort (void)
 422 {
 423 }
 424
 425 static bool_t
 426 clntudp_control (CLIENT *cl, int request, char *info)
 427 {
 428   struct cu_data *cu = (struct cu_data *) cl->cl_private;
 429
 430   switch (request)
 431     {
 432     case CLSET_FD_CLOSE:
 433       cu->cu_closeit = TRUE;
 434       break;
 435     case CLSET_FD_NCLOSE:
 436       cu->cu_closeit = FALSE;
 437       break;
 438     case CLSET_TIMEOUT:
 439       cu->cu_total = *(struct timeval *) info;
 440       break;
 441     case CLGET_TIMEOUT:
 442       *(struct timeval *) info = cu->cu_total;
 443       break;
 444     case CLSET_RETRY_TIMEOUT:
 445       cu->cu_wait = *(struct timeval *) info;
 446       break;
 447     case CLGET_RETRY_TIMEOUT:
 448       *(struct timeval *) info = cu->cu_wait;
 449       break;
 450     case CLGET_SERVER_ADDR:
 451       *(struct sockaddr_in *) info = cu->cu_raddr;
 452       break;
 453     case CLGET_FD:
 454       *(int *)info = cu->cu_sock;
 455       break;
 456     case CLGET_XID:
 457       /*
 458        * use the knowledge that xid is the
 459        * first element in the call structure *.
 460        * This will get the xid of the PREVIOUS call
 461        */
 462       *(u_long *)info = ntohl(*(u_long *)cu->cu_outbuf);
 463       break;
 464     case CLSET_XID:
 465       /* This will set the xid of the NEXT call */
 466       *(u_long *)cu->cu_outbuf =  htonl(*(u_long *)info - 1);
 467       /* decrement by 1 as clntudp_call() increments once */
 468     case CLGET_VERS:
 469       /*
 470        * This RELIES on the information that, in the call body,
 471        * the version number field is the fifth field from the
 472        * begining of the RPC header. MUST be changed if the
 473        * call_struct is changed
 474        */
 475       *(u_long *)info = ntohl(*(u_long *)(cu->cu_outbuf +
 476                                           4 * BYTES_PER_XDR_UNIT));
 477       break;
 478     case CLSET_VERS:
 479       *(u_long *)(cu->cu_outbuf + 4 * BYTES_PER_XDR_UNIT)
 480         = htonl(*(u_long *)info);
 481       break;
 482     case CLGET_PROG:
 483       /*
 484        * This RELIES on the information that, in the call body,
 485        * the program number field is the  field from the
 486        * begining of the RPC header. MUST be changed if the
 487        * call_struct is changed
 488        */
 489       *(u_long *)info = ntohl(*(u_long *)(cu->cu_outbuf +
 490                                           3 * BYTES_PER_XDR_UNIT));
 491       break;
 492     case CLSET_PROG:
 493       *(u_long *)(cu->cu_outbuf + 3 * BYTES_PER_XDR_UNIT)
 494         = htonl(*(u_long *)info);
 495       break;
 496     /* The following are only possible with TI-RPC */
 497     case CLGET_SVC_ADDR:
 498     case CLSET_SVC_ADDR:
 499     case CLSET_PUSH_TIMOD:
 500     case CLSET_POP_TIMOD:
 501     default:
 502       return FALSE;
 503     }
 504   return TRUE;
 505 }
 506
 507 static void
 508 clntudp_destroy (CLIENT *cl)
 509 {
 510   struct cu_data *cu = (struct cu_data *) cl->cl_private;
 511
 512   if (cu->cu_closeit)
 513     {
 514       (void) close (cu->cu_sock);
 515     }
 516   XDR_DESTROY (&(cu->cu_outxdrs));
 517   mem_free ((caddr_t) cu, (sizeof (*cu) + cu->cu_sendsz + cu->cu_recvsz));
 518   mem_free ((caddr_t) cl, sizeof (CLIENT));
 519 }