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                         (void)close(*sockp);
 163                         goto fooy;
 164                 }
 165                 ct->ct_closeit = TRUE;
 166         } else {
 167                 ct->ct_closeit = FALSE;
 168         }
 169
 170         /*
 171          * Set up private data struct
 172          */
 173         ct->ct_sock = *sockp;
 174         ct->ct_wait.tv_usec = 0;
 175         ct->ct_waitset = FALSE;
 176         ct->ct_addr = *raddr;
 177
 178         /*
 179          * Initialize call message
 180          */
 181         (void)gettimeofday(&now, (struct timezone *)0);
 182         call_msg.rm_xid = getpid() ^ now.tv_sec ^ now.tv_usec;
 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 staic 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                 if (ct->ct_closeit) {
 195                         (void)close(*sockp);
 196                 }
 197                 goto fooy;
 198         }
 199         ct->ct_mpos = XDR_GETPOS(&(ct->ct_xdrs));
 200         XDR_DESTROY(&(ct->ct_xdrs));
 201
 202         /*
 203          * Create a client handle which uses xdrrec for serialization
 204          * and authnone for authentication.
 205          */
 206         xdrrec_create(&(ct->ct_xdrs), sendsz, recvsz,
 207             (caddr_t)ct, readtcp, writetcp);
 208         h->cl_ops = &tcp_ops;
 209         h->cl_private = (caddr_t) ct;
 210         h->cl_auth = authnone_create();
 211         return (h);
 212
 213 fooy:
 214         /*
 215          * Something goofed, free stuff and barf
 216          */
 217         mem_free((caddr_t)ct, sizeof(struct ct_data));
 218         mem_free((caddr_t)h, sizeof(CLIENT));
 219         return ((CLIENT *)NULL);
 220 }
 221
 222 static enum clnt_stat
 223 clnttcp_call(h, proc, xdr_args, args_ptr, xdr_results, results_ptr, timeout)
 224         register CLIENT *h;
 225         u_long proc;
 226         xdrproc_t xdr_args;
 227         caddr_t args_ptr;
 228         xdrproc_t xdr_results;
 229         caddr_t results_ptr;
 230         struct timeval timeout;
 231 {
 232         register struct ct_data *ct = (struct ct_data *) h->cl_private;
 233         register XDR *xdrs = &(ct->ct_xdrs);
 234         struct rpc_msg reply_msg;
 235         u_long x_id;
 236         u_long *msg_x_id = (u_long *)(ct->ct_mcall);    /* yuk */
 237         register bool_t shipnow;
 238         int refreshes = 2;
 239
 240         if (!ct->ct_waitset) {
 241                 ct->ct_wait = timeout;
 242         }
 243
 244         shipnow =
 245             (xdr_results == (xdrproc_t)0 && timeout.tv_sec == 0
 246             && timeout.tv_usec == 0) ? FALSE : TRUE;
 247
 248 call_again:
 249         xdrs->x_op = XDR_ENCODE;
 250         ct->ct_error.re_status = RPC_SUCCESS;
 251         x_id = ntohl(--(*msg_x_id));
 252         if ((! XDR_PUTBYTES(xdrs, ct->ct_mcall, ct->ct_mpos)) ||
 253             (! XDR_PUTLONG(xdrs, (long *)&proc)) ||
 254             (! AUTH_MARSHALL(h->cl_auth, xdrs)) ||
 255             (! (*xdr_args)(xdrs, args_ptr))) {
 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 (timeout.tv_sec == 0 && timeout.tv_usec == 0) {
 269                 return(ct->ct_error.re_status = RPC_TIMEDOUT);
 270         }
 271
 272
 273         /*
 274          * Keep receiving until we get a valid transaction id
 275          */
 276         xdrs->x_op = XDR_DECODE;
 277         while (TRUE) {
 278                 reply_msg.acpted_rply.ar_verf = _null_auth;
 279                 reply_msg.acpted_rply.ar_results.where = NULL;
 280                 reply_msg.acpted_rply.ar_results.proc = xdr_void;
 281                 if (! xdrrec_skiprecord(xdrs))
 282                         return (ct->ct_error.re_status);
 283                 /* now decode and validate the response header */
 284                 if (! xdr_replymsg(xdrs, &reply_msg)) {
 285                         if (ct->ct_error.re_status == RPC_SUCCESS)
 286                                 continue;
 287                         return (ct->ct_error.re_status);
 288                 }
 289                 if (reply_msg.rm_xid == x_id)
 290                         break;
 291         }
 292
 293         /*
 294          * process header
 295          */
 296         _seterr_reply(&reply_msg, &(ct->ct_error));
 297         if (ct->ct_error.re_status == RPC_SUCCESS) {
 298                 if (! AUTH_VALIDATE(h->cl_auth, &reply_msg.acpted_rply.ar_verf)) {
 299                         ct->ct_error.re_status = RPC_AUTHERROR;
 300                         ct->ct_error.re_why = AUTH_INVALIDRESP;
 301                 } else if (! (*xdr_results)(xdrs, results_ptr)) {
 302                         if (ct->ct_error.re_status == RPC_SUCCESS)
 303                                 ct->ct_error.re_status = RPC_CANTDECODERES;
 304                 }
 305                 /* free verifier ... */
 306                 if (reply_msg.acpted_rply.ar_verf.oa_base != NULL) {
 307                         xdrs->x_op = XDR_FREE;
 308                         (void)xdr_opaque_auth(xdrs, &(reply_msg.acpted_rply.ar_verf));
 309                 }
 310         }  /* end successful completion */
 311         else {
 312                 /* maybe our credentials need to be refreshed ... */
 313                 if (refreshes-- && AUTH_REFRESH(h->cl_auth))
 314                         goto call_again;
 315         }  /* end of unsuccessful completion */
 316         return (ct->ct_error.re_status);
 317 }
 318
 319 static void
 320 clnttcp_geterr(h, errp)
 321         CLIENT *h;
 322         struct rpc_err *errp;
 323 {
 324         register struct ct_data *ct =
 325             (struct ct_data *) h->cl_private;
 326
 327         *errp = ct->ct_error;
 328 }
 329
 330 static bool_t
 331 clnttcp_freeres(cl, xdr_res, res_ptr)
 332         CLIENT *cl;
 333         xdrproc_t xdr_res;
 334         caddr_t res_ptr;
 335 {
 336         register struct ct_data *ct = (struct ct_data *)cl->cl_private;
 337         register XDR *xdrs = &(ct->ct_xdrs);
 338
 339         xdrs->x_op = XDR_FREE;
 340         return ((*xdr_res)(xdrs, res_ptr));
 341 }
 342
 343 static void
 344 clnttcp_abort()
 345 {
 346 }
 347
 348 static bool_t
 349 clnttcp_control(cl, request, info)
 350         CLIENT *cl;
 351         int request;
 352         char *info;
 353 {
 354         register struct ct_data *ct = (struct ct_data *)cl->cl_private;
 355
 356         switch (request) {
 357         case CLSET_TIMEOUT:
 358                 ct->ct_wait = *(struct timeval *)info;
 359                 ct->ct_waitset = TRUE;
 360                 break;
 361         case CLGET_TIMEOUT:
 362                 *(struct timeval *)info = ct->ct_wait;
 363                 break;
 364         case CLGET_SERVER_ADDR:
 365                 *(struct sockaddr_in *)info = ct->ct_addr;
 366                 break;
 367         default:
 368                 return (FALSE);
 369         }
 370         return (TRUE);
 371 }
 372
 373
 374 static void
 375 clnttcp_destroy(h)
 376         CLIENT *h;
 377 {
 378         register struct ct_data *ct =
 379             (struct ct_data *) h->cl_private;
 380
 381         if (ct->ct_closeit) {
 382                 (void)close(ct->ct_sock);
 383         }
 384         XDR_DESTROY(&(ct->ct_xdrs));
 385         mem_free((caddr_t)ct, sizeof(struct ct_data));
 386         mem_free((caddr_t)h, sizeof(CLIENT));
 387 }
 388
 389 /*
 390  * Interface between xdr serializer and tcp connection.
 391  * Behaves like the system calls, read & write, but keeps some error state
 392  * around for the rpc level.
 393  */
 394 static int
 395 readtcp(ct, buf, len)
 396         register struct ct_data *ct;
 397         caddr_t buf;
 398         register int len;
 399 {
 400 #ifdef FD_SETSIZE
 401         fd_set mask;
 402         fd_set readfds;
 403
 404         if (len == 0)
 405                 return (0);
 406         FD_ZERO(&mask);
 407         FD_SET(ct->ct_sock, &mask);
 408 #else
 409         register int mask = 1 << (ct->ct_sock);
 410         int readfds;
 411
 412         if (len == 0)
 413                 return (0);
 414
 415 #endif /* def FD_SETSIZE */
 416         while (TRUE) {
 417                 readfds = mask;
 418                 switch (select(_rpc_dtablesize(), &readfds, (int*)NULL, (int*)NULL,
 419                                &(ct->ct_wait))) {
 420                 case 0:
 421                         ct->ct_error.re_status = RPC_TIMEDOUT;
 422                         return (-1);
 423
 424                 case -1:
 425                         if (errno == EINTR)
 426                                 continue;
 427                         ct->ct_error.re_status = RPC_CANTRECV;
 428                         ct->ct_error.re_errno = errno;
 429                         return (-1);
 430                 }
 431                 break;
 432         }
 433         switch (len = read(ct->ct_sock, buf, len)) {
 434
 435         case 0:
 436                 /* premature eof */
 437                 ct->ct_error.re_errno = ECONNRESET;
 438                 ct->ct_error.re_status = RPC_CANTRECV;
 439                 len = -1;  /* it's really an error */
 440                 break;
 441
 442         case -1:
 443                 ct->ct_error.re_errno = errno;
 444                 ct->ct_error.re_status = RPC_CANTRECV;
 445                 break;
 446         }
 447         return (len);
 448 }
 449
 450 static int
 451 writetcp(ct, buf, len)
 452         struct ct_data *ct;
 453         caddr_t buf;
 454         int len;
 455 {
 456         register int i, cnt;
 457
 458         for (cnt = len; cnt > 0; cnt -= i, buf += i) {
 459                 if ((i = write(ct->ct_sock, buf, cnt)) == -1) {
 460                         ct->ct_error.re_errno = errno;
 461                         ct->ct_error.re_status = RPC_CANTSEND;
 462                         return (-1);
 463                 }
 464         }
 465         return (len);
 466 }