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