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