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