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