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