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