sunrpc/clnt_udp.c

   1 /* @(#)clnt_udp.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_udp.c 1.39 87/08/11 Copyr 1984 Sun Micro";
  32 #endif
  33
  34 /*
  35  * clnt_udp.c, Implements a UDP/IP based, client side RPC.
  36  *
  37  * Copyright (C) 1984, Sun Microsystems, Inc.
  38  */
  39
  40 #include <stdio.h>
  41 #include <rpc/rpc.h>
  42 #include <sys/socket.h>
  43 #include <sys/ioctl.h>
  44 #include <netdb.h>
  45 #include <errno.h>
  46 #include <rpc/pmap_clnt.h>
  47
  48 extern int errno;
  49
  50 /*
  51  * UDP bases client side rpc operations
  52  */
  53 static enum clnt_stat   clntudp_call();
  54 static void             clntudp_abort();
  55 static void             clntudp_geterr();
  56 static bool_t           clntudp_freeres();
  57 static bool_t           clntudp_control();
  58 static void             clntudp_destroy();
  59
  60 static struct clnt_ops udp_ops = {
  61         clntudp_call,
  62         clntudp_abort,
  63         clntudp_geterr,
  64         clntudp_freeres,
  65         clntudp_destroy,
  66         clntudp_control
  67 };
  68
  69 /*
  70  * Private data kept per client handle
  71  */
  72 struct cu_data {
  73         int                cu_sock;
  74         bool_t             cu_closeit;
  75         struct sockaddr_in cu_raddr;
  76         int                cu_rlen;
  77         struct timeval     cu_wait;
  78         struct timeval     cu_total;
  79         struct rpc_err     cu_error;
  80         XDR                cu_outxdrs;
  81         u_int              cu_xdrpos;
  82         u_int              cu_sendsz;
  83         char               *cu_outbuf;
  84         u_int              cu_recvsz;
  85         char               cu_inbuf[1];
  86 };
  87
  88 /*
  89  * Create a UDP based client handle.
  90  * If *sockp<0, *sockp is set to a newly created UPD socket.
  91  * If raddr->sin_port is 0 a binder on the remote machine
  92  * is consulted for the correct port number.
  93  * NB: It is the clients responsibility to close *sockp.
  94  * NB: The rpch->cl_auth is initialized to null authentication.
  95  *     Caller may wish to set this something more useful.
  96  *
  97  * wait is the amount of time used between retransmitting a call if
  98  * no response has been heard;  retransmition occurs until the actual
  99  * rpc call times out.
 100  *
 101  * sendsz and recvsz are the maximum allowable packet sizes that can be
 102  * sent and received.
 103  */
 104 CLIENT *
 105 clntudp_bufcreate(raddr, program, version, wait, sockp, sendsz, recvsz)
 106         struct sockaddr_in *raddr;
 107         u_long program;
 108         u_long version;
 109         struct timeval wait;
 110         register int *sockp;
 111         u_int sendsz;
 112         u_int recvsz;
 113 {
 114         CLIENT *cl;
 115         register struct cu_data *cu;
 116         struct timeval now;
 117         struct rpc_msg call_msg;
 118
 119         cl = (CLIENT *)mem_alloc(sizeof(CLIENT));
 120         if (cl == NULL) {
 121                 (void) fprintf(stderr, "clntudp_create: out of memory\n");
 122                 rpc_createerr.cf_stat = RPC_SYSTEMERROR;
 123                 rpc_createerr.cf_error.re_errno = errno;
 124                 goto fooy;
 125         }
 126         sendsz = ((sendsz + 3) / 4) * 4;
 127         recvsz = ((recvsz + 3) / 4) * 4;
 128         cu = (struct cu_data *)mem_alloc(sizeof(*cu) + sendsz + recvsz);
 129         if (cu == NULL) {
 130                 (void) fprintf(stderr, "clntudp_create: out of memory\n");
 131                 rpc_createerr.cf_stat = RPC_SYSTEMERROR;
 132                 rpc_createerr.cf_error.re_errno = errno;
 133                 goto fooy;
 134         }
 135         cu->cu_outbuf = &cu->cu_inbuf[recvsz];
 136
 137         (void)gettimeofday(&now, (struct timezone *)0);
 138         if (raddr->sin_port == 0) {
 139                 u_short port;
 140                 if ((port =
 141                     pmap_getport(raddr, program, version, IPPROTO_UDP)) == 0) {
 142                         goto fooy;
 143                 }
 144                 raddr->sin_port = htons(port);
 145         }
 146         cl->cl_ops = &udp_ops;
 147         cl->cl_private = (caddr_t)cu;
 148         cu->cu_raddr = *raddr;
 149         cu->cu_rlen = sizeof (cu->cu_raddr);
 150         cu->cu_wait = wait;
 151         cu->cu_total.tv_sec = -1;
 152         cu->cu_total.tv_usec = -1;
 153         cu->cu_sendsz = sendsz;
 154         cu->cu_recvsz = recvsz;
 155         call_msg.rm_xid = getpid() ^ now.tv_sec ^ now.tv_usec;
 156         call_msg.rm_direction = CALL;
 157         call_msg.rm_call.cb_rpcvers = RPC_MSG_VERSION;
 158         call_msg.rm_call.cb_prog = program;
 159         call_msg.rm_call.cb_vers = version;
 160         xdrmem_create(&(cu->cu_outxdrs), cu->cu_outbuf,
 161             sendsz, XDR_ENCODE);
 162         if (! xdr_callhdr(&(cu->cu_outxdrs), &call_msg)) {
 163                 goto fooy;
 164         }
 165         cu->cu_xdrpos = XDR_GETPOS(&(cu->cu_outxdrs));
 166         if (*sockp < 0) {
 167                 int dontblock = 1;
 168
 169                 *sockp = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
 170                 if (*sockp < 0) {
 171                         rpc_createerr.cf_stat = RPC_SYSTEMERROR;
 172                         rpc_createerr.cf_error.re_errno = errno;
 173                         goto fooy;
 174                 }
 175                 /* attempt to bind to prov port */
 176                 (void)bindresvport(*sockp, (struct sockaddr_in *)0);
 177                 /* the sockets rpc controls are non-blocking */
 178                 (void)ioctl(*sockp, FIONBIO, (char *) &dontblock);
 179                 cu->cu_closeit = TRUE;
 180         } else {
 181                 cu->cu_closeit = FALSE;
 182         }
 183         cu->cu_sock = *sockp;
 184         cl->cl_auth = authnone_create();
 185         return (cl);
 186 fooy:
 187         if (cu)
 188                 mem_free((caddr_t)cu, sizeof(*cu) + sendsz + recvsz);
 189         if (cl)
 190                 mem_free((caddr_t)cl, sizeof(CLIENT));
 191         return ((CLIENT *)NULL);
 192 }
 193
 194 CLIENT *
 195 clntudp_create(raddr, program, version, wait, sockp)
 196         struct sockaddr_in *raddr;
 197         u_long program;
 198         u_long version;
 199         struct timeval wait;
 200         register int *sockp;
 201 {
 202
 203         return(clntudp_bufcreate(raddr, program, version, wait, sockp,
 204             UDPMSGSIZE, UDPMSGSIZE));
 205 }
 206
 207 static enum clnt_stat
 208 clntudp_call(cl, proc, xargs, argsp, xresults, resultsp, utimeout)
 209         register CLIENT *cl;            /* client handle */
 210         u_long          proc;           /* procedure number */
 211         xdrproc_t       xargs;          /* xdr routine for args */
 212         caddr_t         argsp;          /* pointer to args */
 213         xdrproc_t       xresults;       /* xdr routine for results */
 214         caddr_t         resultsp;       /* pointer to results */
 215         struct timeval  utimeout;       /* seconds to wait before giving up */
 216 {
 217         register struct cu_data *cu = (struct cu_data *)cl->cl_private;
 218         register XDR *xdrs;
 219         register int outlen;
 220         register int inlen;
 221         int fromlen;
 222 #ifdef FD_SETSIZE
 223         fd_set readfds;
 224         fd_set mask;
 225 #else
 226         int readfds;
 227         register int mask;
 228 #endif /* def FD_SETSIZE */
 229         struct sockaddr_in from;
 230         struct rpc_msg reply_msg;
 231         XDR reply_xdrs;
 232         struct timeval time_waited;
 233         bool_t ok;
 234         int nrefreshes = 2;     /* number of times to refresh cred */
 235         struct timeval timeout;
 236
 237         if (cu->cu_total.tv_usec == -1) {
 238                 timeout = utimeout;     /* use supplied timeout */
 239         } else {
 240                 timeout = cu->cu_total; /* use default timeout */
 241         }
 242
 243         time_waited.tv_sec = 0;
 244         time_waited.tv_usec = 0;
 245 call_again:
 246         xdrs = &(cu->cu_outxdrs);
 247         xdrs->x_op = XDR_ENCODE;
 248         XDR_SETPOS(xdrs, cu->cu_xdrpos);
 249         /*
 250          * the transaction is the first thing in the out buffer
 251          */
 252         (*(u_short *)(cu->cu_outbuf))++;
 253         if ((! XDR_PUTLONG(xdrs, (long *)&proc)) ||
 254             (! AUTH_MARSHALL(cl->cl_auth, xdrs)) ||
 255             (! (*xargs)(xdrs, argsp)))
 256                 return (cu->cu_error.re_status = RPC_CANTENCODEARGS);
 257         outlen = (int)XDR_GETPOS(xdrs);
 258
 259 send_again:
 260         if (sendto(cu->cu_sock, cu->cu_outbuf, outlen, 0,
 261             (struct sockaddr *)&(cu->cu_raddr), cu->cu_rlen)
 262             != outlen) {
 263                 cu->cu_error.re_errno = errno;
 264                 return (cu->cu_error.re_status = RPC_CANTSEND);
 265         }
 266
 267         /*
 268          * Hack to provide rpc-based message passing
 269          */
 270         if (timeout.tv_sec == 0 && timeout.tv_usec == 0) {
 271                 return (cu->cu_error.re_status = RPC_TIMEDOUT);
 272         }
 273         /*
 274          * sub-optimal code appears here because we have
 275          * some clock time to spare while the packets are in flight.
 276          * (We assume that this is actually only executed once.)
 277          */
 278         reply_msg.acpted_rply.ar_verf = _null_auth;
 279         reply_msg.acpted_rply.ar_results.where = resultsp;
 280         reply_msg.acpted_rply.ar_results.proc = xresults;
 281 #ifdef FD_SETSIZE
 282         FD_ZERO(&mask);
 283         FD_SET(cu->cu_sock, &mask);
 284 #else
 285         mask = 1 << cu->cu_sock;
 286 #endif /* def FD_SETSIZE */
 287         for (;;) {
 288                 readfds = mask;
 289                 switch (select(_rpc_dtablesize(), &readfds, (int *)NULL,
 290                                (int *)NULL, &(cu->cu_wait))) {
 291
 292                 case 0:
 293                         time_waited.tv_sec += cu->cu_wait.tv_sec;
 294                         time_waited.tv_usec += cu->cu_wait.tv_usec;
 295                         while (time_waited.tv_usec >= 1000000) {
 296                                 time_waited.tv_sec++;
 297                                 time_waited.tv_usec -= 1000000;
 298                         }
 299                         if ((time_waited.tv_sec < timeout.tv_sec) ||
 300                                 ((time_waited.tv_sec == timeout.tv_sec) &&
 301                                 (time_waited.tv_usec < timeout.tv_usec)))
 302                                 goto send_again;
 303                         return (cu->cu_error.re_status = RPC_TIMEDOUT);
 304
 305                 /*
 306                  * buggy in other cases because time_waited is not being
 307                  * updated.
 308                  */
 309                 case -1:
 310                         if (errno == EINTR)
 311                                 continue;
 312                         cu->cu_error.re_errno = errno;
 313                         return (cu->cu_error.re_status = RPC_CANTRECV);
 314                 }
 315                 do {
 316                         fromlen = sizeof(struct sockaddr);
 317                         inlen = recvfrom(cu->cu_sock, cu->cu_inbuf,
 318                                 (int) cu->cu_recvsz, 0,
 319                                 (struct sockaddr *)&from, &fromlen);
 320                 } while (inlen < 0 && errno == EINTR);
 321                 if (inlen < 0) {
 322                         if (errno == EWOULDBLOCK)
 323                                 continue;
 324                         cu->cu_error.re_errno = errno;
 325                         return (cu->cu_error.re_status = RPC_CANTRECV);
 326                 }
 327                 if (inlen < 4)
 328                         continue;
 329                 /* see if reply transaction id matches sent id */
 330                 if (*((u_int32_t *)(cu->cu_inbuf)) != *((u_int32_t *)(cu->cu_outbuf)))
 331                         continue;
 332                 /* we now assume we have the proper reply */
 333                 break;
 334         }
 335
 336         /*
 337          * now decode and validate the response
 338          */
 339         xdrmem_create(&reply_xdrs, cu->cu_inbuf, (u_int)inlen, XDR_DECODE);
 340         ok = xdr_replymsg(&reply_xdrs, &reply_msg);
 341         /* XDR_DESTROY(&reply_xdrs);  save a few cycles on noop destroy */
 342         if (ok) {
 343                 _seterr_reply(&reply_msg, &(cu->cu_error));
 344                 if (cu->cu_error.re_status == RPC_SUCCESS) {
 345                         if (! AUTH_VALIDATE(cl->cl_auth,
 346                                 &reply_msg.acpted_rply.ar_verf)) {
 347                                 cu->cu_error.re_status = RPC_AUTHERROR;
 348                                 cu->cu_error.re_why = AUTH_INVALIDRESP;
 349                         }
 350                         if (reply_msg.acpted_rply.ar_verf.oa_base != NULL) {
 351                                 xdrs->x_op = XDR_FREE;
 352                                 (void)xdr_opaque_auth(xdrs,
 353                                     &(reply_msg.acpted_rply.ar_verf));
 354                         }
 355                 }  /* end successful completion */
 356                 else {
 357                         /* maybe our credentials need to be refreshed ... */
 358                         if (nrefreshes > 0 && AUTH_REFRESH(cl->cl_auth)) {
 359                                 nrefreshes--;
 360                                 goto call_again;
 361                         }
 362                 }  /* end of unsuccessful completion */
 363         }  /* end of valid reply message */
 364         else {
 365                 cu->cu_error.re_status = RPC_CANTDECODERES;
 366         }
 367         return (cu->cu_error.re_status);
 368 }
 369
 370 static void
 371 clntudp_geterr(cl, errp)
 372         CLIENT *cl;
 373         struct rpc_err *errp;
 374 {
 375         register struct cu_data *cu = (struct cu_data *)cl->cl_private;
 376
 377         *errp = cu->cu_error;
 378 }
 379
 380
 381 static bool_t
 382 clntudp_freeres(cl, xdr_res, res_ptr)
 383         CLIENT *cl;
 384         xdrproc_t xdr_res;
 385         caddr_t res_ptr;
 386 {
 387         register struct cu_data *cu = (struct cu_data *)cl->cl_private;
 388         register XDR *xdrs = &(cu->cu_outxdrs);
 389
 390         xdrs->x_op = XDR_FREE;
 391         return ((*xdr_res)(xdrs, res_ptr));
 392 }
 393
 394 static void
 395 clntudp_abort(/*h*/)
 396         /*CLIENT *h;*/
 397 {
 398 }
 399
 400 static bool_t
 401 clntudp_control(cl, request, info)
 402         CLIENT *cl;
 403         int request;
 404         char *info;
 405 {
 406         register struct cu_data *cu = (struct cu_data *)cl->cl_private;
 407
 408         switch (request) {
 409         case CLSET_TIMEOUT:
 410                 cu->cu_total = *(struct timeval *)info;
 411                 break;
 412         case CLGET_TIMEOUT:
 413                 *(struct timeval *)info = cu->cu_total;
 414                 break;
 415         case CLSET_RETRY_TIMEOUT:
 416                 cu->cu_wait = *(struct timeval *)info;
 417                 break;
 418         case CLGET_RETRY_TIMEOUT:
 419                 *(struct timeval *)info = cu->cu_wait;
 420                 break;
 421         case CLGET_SERVER_ADDR:
 422                 *(struct sockaddr_in *)info = cu->cu_raddr;
 423                 break;
 424         default:
 425                 return (FALSE);
 426         }
 427         return (TRUE);
 428 }
 429
 430 static void
 431 clntudp_destroy(cl)
 432         CLIENT *cl;
 433 {
 434         register struct cu_data *cu = (struct cu_data *)cl->cl_private;
 435
 436         if (cu->cu_closeit) {
 437                 (void)close(cu->cu_sock);
 438         }
 439         XDR_DESTROY(&(cu->cu_outxdrs));
 440         mem_free((caddr_t)cu, (sizeof(*cu) + cu->cu_sendsz + cu->cu_recvsz));
 441         mem_free((caddr_t)cl, sizeof(CLIENT));
 442 }