sunrpc/clnt_tcp.c

   1 /* @(#)clnt_tcp.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_tcp.c 1.37 87/10/05 Copyr 1984 Sun Micro";
  32 #endif
  33
  34 /*
  35  * clnt_tcp.c, Implements a TCP/IP based, client side RPC.
  36  *
  37  * Copyright (C) 1984, Sun Microsystems, Inc.
  38  *
  39  * TCP based RPC supports 'batched calls'.
  40  * A sequence of calls may be batched-up in a send buffer.  The rpc call
  41  * return immediately to the client even though the call was not necessarily
  42  * sent.  The batching occurs if the results' xdr routine is NULL (0) AND
  43  * the rpc timeout value is zero (see clnt.h, rpc).
  44  *
  45  * Clients should NOT casually batch calls that in fact return results; that is,
  46  * the server side should be aware that a call is batched and not produce any
  47  * return message.  Batched calls that produce many result messages can
  48  * deadlock (netlock) the client and the server....
  49  *
  50  * Now go hang yourself.
  51  */
  52
  53 #include <netdb.h>
  54 #include <errno.h>
  55 #include <stdio.h>
  56 #include <unistd.h>
  57 #include <libintl.h>
  58 #include <rpc/rpc.h>
  59 #include <sys/poll.h>
  60 #include <sys/socket.h>
  61 #include <rpc/pmap_clnt.h>
  62 #ifdef USE_IN_LIBIO
  63 # include <wchar.h>
  64 #endif
  65
  66 extern u_long _create_xid (void);
  67
  68 #define MCALL_MSG_SIZE 24
  69
  70 struct ct_data
  71   {
  72     int ct_sock;
  73     bool_t ct_closeit;
  74     struct timeval ct_wait;
  75     bool_t ct_waitset;          /* wait set by clnt_control? */
  76     struct sockaddr_in ct_addr;
  77     struct rpc_err ct_error;
  78     char ct_mcall[MCALL_MSG_SIZE];      /* marshalled callmsg */
  79     u_int ct_mpos;              /* pos after marshal */
  80     XDR ct_xdrs;
  81   };
  82
  83 static int readtcp (char *, char *, int);
  84 static int writetcp (char *, char *, int);
  85
  86 static enum clnt_stat clnttcp_call (CLIENT *, u_long, xdrproc_t, caddr_t,
  87                                     xdrproc_t, caddr_t, struct timeval);
  88 static void clnttcp_abort (void);
  89 static void clnttcp_geterr (CLIENT *, struct rpc_err *);
  90 static bool_t clnttcp_freeres (CLIENT *, xdrproc_t, caddr_t);
  91 static bool_t clnttcp_control (CLIENT *, int, char *);
  92 static void clnttcp_destroy (CLIENT *);
  93
  94 static struct clnt_ops tcp_ops =
  95 {
  96   clnttcp_call,
  97   clnttcp_abort,
  98   clnttcp_geterr,
  99   clnttcp_freeres,
 100   clnttcp_destroy,
 101   clnttcp_control
 102 };
 103
 104 /*
 105  * Create a client handle for a tcp/ip connection.
 106  * If *sockp<0, *sockp is set to a newly created TCP socket and it is
 107  * connected to raddr.  If *sockp non-negative then
 108  * raddr is ignored.  The rpc/tcp package does buffering
 109  * similar to stdio, so the client must pick send and receive buffer sizes,];
 110  * 0 => use the default.
 111  * If raddr->sin_port is 0, then a binder on the remote machine is
 112  * consulted for the right port number.
 113  * NB: *sockp is copied into a private area.
 114  * NB: It is the clients responsibility to close *sockp.
 115  * NB: The rpch->cl_auth is set null authentication.  Caller may wish to set this
 116  * something more useful.
 117  */
 118 CLIENT *
 119 clnttcp_create (struct sockaddr_in *raddr, u_long prog, u_long vers,
 120                 int *sockp, u_int sendsz, u_int recvsz)
 121 {
 122   CLIENT *h;
 123   struct ct_data *ct;
 124   struct rpc_msg call_msg;
 125
 126   h = (CLIENT *) mem_alloc (sizeof (*h));
 127   ct = (struct ct_data *) mem_alloc (sizeof (*ct));
 128   if (h == NULL || ct == NULL)
 129     {
 130       struct rpc_createerr *ce = &get_rpc_createerr ();
 131 #ifdef USE_IN_LIBIO
 132       if (_IO_fwide (stderr, 0) > 0)
 133         (void) __fwprintf (stderr, L"%s",
 134                            _("clnttcp_create: out of memory\n"));
 135       else
 136 #endif
 137         (void) fputs (_("clnttcp_create: out of memory\n"), stderr);
 138       ce->cf_stat = RPC_SYSTEMERROR;
 139       ce->cf_error.re_errno = ENOMEM;
 140       goto fooy;
 141     }
 142
 143   /*
 144    * If no port number given ask the pmap for one
 145    */
 146   if (raddr->sin_port == 0)
 147     {
 148       u_short port;
 149       if ((port = pmap_getport (raddr, prog, vers, IPPROTO_TCP)) == 0)
 150         {
 151           mem_free ((caddr_t) ct, sizeof (struct ct_data));
 152           mem_free ((caddr_t) h, sizeof (CLIENT));
 153           return ((CLIENT *) NULL);
 154         }
 155       raddr->sin_port = htons (port);
 156     }
 157
 158   /*
 159    * If no socket given, open one
 160    */
 161   if (*sockp < 0)
 162     {
 163       *sockp = __socket (AF_INET, SOCK_STREAM, IPPROTO_TCP);
 164       (void) bindresvport (*sockp, (struct sockaddr_in *) 0);
 165       if ((*sockp < 0)
 166           || (__connect (*sockp, (struct sockaddr *) raddr,
 167                          sizeof (*raddr)) < 0))
 168         {
 169           struct rpc_createerr *ce = &get_rpc_createerr ();
 170           ce->cf_stat = RPC_SYSTEMERROR;
 171           ce->cf_error.re_errno = errno;
 172           if (*sockp >= 0)
 173             (void) __close (*sockp);
 174           goto fooy;
 175         }
 176       ct->ct_closeit = TRUE;
 177     }
 178   else
 179     {
 180       ct->ct_closeit = FALSE;
 181     }
 182
 183   /*
 184    * Set up private data struct
 185    */
 186   ct->ct_sock = *sockp;
 187   ct->ct_wait.tv_usec = 0;
 188   ct->ct_waitset = FALSE;
 189   ct->ct_addr = *raddr;
 190
 191   /*
 192    * Initialize call message
 193    */
 194   call_msg.rm_xid = _create_xid ();
 195   call_msg.rm_direction = CALL;
 196   call_msg.rm_call.cb_rpcvers = RPC_MSG_VERSION;
 197   call_msg.rm_call.cb_prog = prog;
 198   call_msg.rm_call.cb_vers = vers;
 199
 200   /*
 201    * pre-serialize the static part of the call msg and stash it away
 202    */
 203   INTUSE(xdrmem_create) (&(ct->ct_xdrs), ct->ct_mcall, MCALL_MSG_SIZE,
 204                          XDR_ENCODE);
 205   if (!INTUSE(xdr_callhdr) (&(ct->ct_xdrs), &call_msg))
 206     {
 207       if (ct->ct_closeit)
 208         {
 209           (void) __close (*sockp);
 210         }
 211       goto fooy;
 212     }
 213   ct->ct_mpos = XDR_GETPOS (&(ct->ct_xdrs));
 214   XDR_DESTROY (&(ct->ct_xdrs));
 215
 216   /*
 217    * Create a client handle which uses xdrrec for serialization
 218    * and authnone for authentication.
 219    */
 220   INTUSE(xdrrec_create) (&(ct->ct_xdrs), sendsz, recvsz,
 221                          (caddr_t) ct, readtcp, writetcp);
 222   h->cl_ops = &tcp_ops;
 223   h->cl_private = (caddr_t) ct;
 224   h->cl_auth = INTUSE(authnone_create) ();
 225   return h;
 226
 227 fooy:
 228   /*
 229    * Something goofed, free stuff and barf
 230    */
 231   mem_free ((caddr_t) ct, sizeof (struct ct_data));
 232   mem_free ((caddr_t) h, sizeof (CLIENT));
 233   return ((CLIENT *) NULL);
 234 }
 235 INTDEF (clnttcp_create)
 236
 237 static enum clnt_stat
 238 clnttcp_call (h, proc, xdr_args, args_ptr, xdr_results, results_ptr, timeout)
 239      CLIENT *h;
 240      u_long proc;
 241      xdrproc_t xdr_args;
 242      caddr_t args_ptr;
 243      xdrproc_t xdr_results;
 244      caddr_t results_ptr;
 245      struct timeval timeout;
 246 {
 247   struct ct_data *ct = (struct ct_data *) h->cl_private;
 248   XDR *xdrs = &(ct->ct_xdrs);
 249   struct rpc_msg reply_msg;
 250   u_long x_id;
 251   u_int32_t *msg_x_id = (u_int32_t *) (ct->ct_mcall);   /* yuk */
 252   bool_t shipnow;
 253   int refreshes = 2;
 254
 255   if (!ct->ct_waitset)
 256     {
 257       ct->ct_wait = timeout;
 258     }
 259
 260   shipnow =
 261     (xdr_results == (xdrproc_t) 0 && ct->ct_wait.tv_sec == 0
 262      && ct->ct_wait.tv_usec == 0) ? FALSE : TRUE;
 263
 264 call_again:
 265   xdrs->x_op = XDR_ENCODE;
 266   ct->ct_error.re_status = RPC_SUCCESS;
 267   x_id = ntohl (--(*msg_x_id));
 268   if ((!XDR_PUTBYTES (xdrs, ct->ct_mcall, ct->ct_mpos)) ||
 269       (!XDR_PUTLONG (xdrs, (long *) &proc)) ||
 270       (!AUTH_MARSHALL (h->cl_auth, xdrs)) ||
 271       (!(*xdr_args) (xdrs, args_ptr)))
 272     {
 273       if (ct->ct_error.re_status == RPC_SUCCESS)
 274         ct->ct_error.re_status = RPC_CANTENCODEARGS;
 275       (void) INTUSE(xdrrec_endofrecord) (xdrs, TRUE);
 276       return (ct->ct_error.re_status);
 277     }
 278   if (!INTUSE(xdrrec_endofrecord) (xdrs, shipnow))
 279     return ct->ct_error.re_status = RPC_CANTSEND;
 280   if (!shipnow)
 281     return RPC_SUCCESS;
 282   /*
 283    * Hack to provide rpc-based message passing
 284    */
 285   if (ct->ct_wait.tv_sec == 0 && ct->ct_wait.tv_usec == 0)
 286     {
 287       return ct->ct_error.re_status = RPC_TIMEDOUT;
 288     }
 289
 290
 291   /*
 292    * Keep receiving until we get a valid transaction id
 293    */
 294   xdrs->x_op = XDR_DECODE;
 295   while (TRUE)
 296     {
 297       reply_msg.acpted_rply.ar_verf = _null_auth;
 298       reply_msg.acpted_rply.ar_results.where = NULL;
 299       reply_msg.acpted_rply.ar_results.proc = (xdrproc_t)INTUSE(xdr_void);
 300       if (!INTUSE(xdrrec_skiprecord) (xdrs))
 301         return (ct->ct_error.re_status);
 302       /* now decode and validate the response header */
 303       if (!INTUSE(xdr_replymsg) (xdrs, &reply_msg))
 304         {
 305           if (ct->ct_error.re_status == RPC_SUCCESS)
 306             continue;
 307           return ct->ct_error.re_status;
 308         }
 309       if ((u_int32_t) reply_msg.rm_xid == (u_int32_t) x_id)
 310         break;
 311     }
 312
 313   /*
 314    * process header
 315    */
 316   _seterr_reply (&reply_msg, &(ct->ct_error));
 317   if (ct->ct_error.re_status == RPC_SUCCESS)
 318     {
 319       if (!AUTH_VALIDATE (h->cl_auth, &reply_msg.acpted_rply.ar_verf))
 320         {
 321           ct->ct_error.re_status = RPC_AUTHERROR;
 322           ct->ct_error.re_why = AUTH_INVALIDRESP;
 323         }
 324       else if (!(*xdr_results) (xdrs, results_ptr))
 325         {
 326           if (ct->ct_error.re_status == RPC_SUCCESS)
 327             ct->ct_error.re_status = RPC_CANTDECODERES;
 328         }
 329       /* free verifier ... */
 330       if (reply_msg.acpted_rply.ar_verf.oa_base != NULL)
 331         {
 332           xdrs->x_op = XDR_FREE;
 333           (void) INTUSE(xdr_opaque_auth) (xdrs,
 334                                           &(reply_msg.acpted_rply.ar_verf));
 335         }
 336     }                           /* end successful completion */
 337   else
 338     {
 339       /* maybe our credentials need to be refreshed ... */
 340       if (refreshes-- && AUTH_REFRESH (h->cl_auth))
 341         goto call_again;
 342     }                           /* end of unsuccessful completion */
 343   return ct->ct_error.re_status;
 344 }
 345
 346 static void
 347 clnttcp_geterr (h, errp)
 348      CLIENT *h;
 349      struct rpc_err *errp;
 350 {
 351   struct ct_data *ct =
 352   (struct ct_data *) h->cl_private;
 353
 354   *errp = ct->ct_error;
 355 }
 356
 357 static bool_t
 358 clnttcp_freeres (cl, xdr_res, res_ptr)
 359      CLIENT *cl;
 360      xdrproc_t xdr_res;
 361      caddr_t res_ptr;
 362 {
 363   struct ct_data *ct = (struct ct_data *) cl->cl_private;
 364   XDR *xdrs = &(ct->ct_xdrs);
 365
 366   xdrs->x_op = XDR_FREE;
 367   return (*xdr_res) (xdrs, res_ptr);
 368 }
 369
 370 static void
 371 clnttcp_abort ()
 372 {
 373 }
 374
 375 static bool_t
 376 clnttcp_control (CLIENT *cl, int request, char *info)
 377 {
 378   struct ct_data *ct = (struct ct_data *) cl->cl_private;
 379
 380
 381   switch (request)
 382     {
 383     case CLSET_FD_CLOSE:
 384       ct->ct_closeit = TRUE;
 385       break;
 386     case CLSET_FD_NCLOSE:
 387       ct->ct_closeit = FALSE;
 388       break;
 389     case CLSET_TIMEOUT:
 390       ct->ct_wait = *(struct timeval *) info;
 391       ct->ct_waitset = TRUE;
 392       break;
 393     case CLGET_TIMEOUT:
 394       *(struct timeval *) info = ct->ct_wait;
 395       break;
 396     case CLGET_SERVER_ADDR:
 397       *(struct sockaddr_in *) info = ct->ct_addr;
 398       break;
 399     case CLGET_FD:
 400       *(int *)info = ct->ct_sock;
 401       break;
 402     case CLGET_XID:
 403       /*
 404        * use the knowledge that xid is the
 405        * first element in the call structure *.
 406        * This will get the xid of the PREVIOUS call
 407        */
 408       *(u_long *)info = ntohl (*(u_long *)ct->ct_mcall);
 409       break;
 410     case CLSET_XID:
 411       /* This will set the xid of the NEXT call */
 412       *(u_long *)ct->ct_mcall =  htonl (*(u_long *)info - 1);
 413       /* decrement by 1 as clnttcp_call() increments once */
 414     case CLGET_VERS:
 415       /*
 416        * This RELIES on the information that, in the call body,
 417        * the version number field is the fifth field from the
 418        * begining of the RPC header. MUST be changed if the
 419        * call_struct is changed
 420        */
 421       *(u_long *)info = ntohl (*(u_long *)(ct->ct_mcall +
 422                                            4 * BYTES_PER_XDR_UNIT));
 423       break;
 424     case CLSET_VERS:
 425       *(u_long *)(ct->ct_mcall + 4 * BYTES_PER_XDR_UNIT)
 426         = htonl (*(u_long *)info);
 427       break;
 428     case CLGET_PROG:
 429       /*
 430        * This RELIES on the information that, in the call body,
 431        * the program number field is the  field from the
 432        * begining of the RPC header. MUST be changed if the
 433        * call_struct is changed
 434        */
 435       *(u_long *)info = ntohl(*(u_long *)(ct->ct_mcall +
 436                                           3 * BYTES_PER_XDR_UNIT));
 437       break;
 438     case CLSET_PROG:
 439       *(u_long *)(ct->ct_mcall + 3 * BYTES_PER_XDR_UNIT)
 440         = htonl(*(u_long *)info);
 441       break;
 442     /* The following are only possible with TI-RPC */
 443     case CLGET_RETRY_TIMEOUT:
 444     case CLSET_RETRY_TIMEOUT:
 445     case CLGET_SVC_ADDR:
 446     case CLSET_SVC_ADDR:
 447     case CLSET_PUSH_TIMOD:
 448     case CLSET_POP_TIMOD:
 449     default:
 450       return FALSE;
 451     }
 452   return TRUE;
 453 }
 454
 455
 456 static void
 457 clnttcp_destroy (CLIENT *h)
 458 {
 459   struct ct_data *ct =
 460   (struct ct_data *) h->cl_private;
 461
 462   if (ct->ct_closeit)
 463     {
 464       (void) __close (ct->ct_sock);
 465     }
 466   XDR_DESTROY (&(ct->ct_xdrs));
 467   mem_free ((caddr_t) ct, sizeof (struct ct_data));
 468   mem_free ((caddr_t) h, sizeof (CLIENT));
 469 }
 470
 471 /*
 472  * Interface between xdr serializer and tcp connection.
 473  * Behaves like the system calls, read & write, but keeps some error state
 474  * around for the rpc level.
 475  */
 476 static int
 477 readtcp (char *ctptr, char *buf, int len)
 478 {
 479   struct ct_data *ct = (struct ct_data *)ctptr;
 480   struct pollfd fd;
 481   int milliseconds = (ct->ct_wait.tv_sec * 1000) +
 482     (ct->ct_wait.tv_usec / 1000);
 483
 484   if (len == 0)
 485     return 0;
 486
 487   fd.fd = ct->ct_sock;
 488   fd.events = POLLIN;
 489   while (TRUE)
 490     {
 491       switch (__poll(&fd, 1, milliseconds))
 492         {
 493         case 0:
 494           ct->ct_error.re_status = RPC_TIMEDOUT;
 495           return -1;
 496
 497         case -1:
 498           if (errno == EINTR)
 499             continue;
 500           ct->ct_error.re_status = RPC_CANTRECV;
 501           ct->ct_error.re_errno = errno;
 502           return -1;
 503         }
 504       break;
 505     }
 506   switch (len = __read (ct->ct_sock, buf, len))
 507     {
 508
 509     case 0:
 510       /* premature eof */
 511       ct->ct_error.re_errno = ECONNRESET;
 512       ct->ct_error.re_status = RPC_CANTRECV;
 513       len = -1;                 /* it's really an error */
 514       break;
 515
 516     case -1:
 517       ct->ct_error.re_errno = errno;
 518       ct->ct_error.re_status = RPC_CANTRECV;
 519       break;
 520     }
 521   return len;
 522 }
 523
 524 static int
 525 writetcp (char *ctptr, char *buf, int len)
 526 {
 527   int i, cnt;
 528   struct ct_data *ct = (struct ct_data*)ctptr;
 529
 530   for (cnt = len; cnt > 0; cnt -= i, buf += i)
 531     {
 532       if ((i = __write (ct->ct_sock, buf, cnt)) == -1)
 533         {
 534           ct->ct_error.re_errno = errno;
 535           ct->ct_error.re_status = RPC_CANTSEND;
 536           return -1;
 537         }
 538     }
 539   return len;
 540 }