sunrpc/svc_tcp.c

   1 /* @(#)svc_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[] = "@(#)svc_tcp.c 1.21 87/08/11 Copyr 1984 Sun Micro";
  32 #endif
  33
  34 /*
  35  * svc_tcp.c, Server side for TCP/IP based RPC.
  36  *
  37  * Copyright (C) 1984, Sun Microsystems, Inc.
  38  *
  39  * Actually implements two flavors of transporter -
  40  * a tcp rendezvouser (a listener and connection establisher)
  41  * and a record/tcp stream.
  42  */
  43
  44 #include <stdio.h>
  45 #include <unistd.h>
  46 #include <string.h>
  47 #include <rpc/rpc.h>
  48 #include <sys/socket.h>
  49 #include <errno.h>
  50 #include <stdlib.h>
  51
  52 #ifdef USE_IN_LIBIO
  53 # include <libio/iolibio.h>
  54 # define fputs(s, f) _IO_fputs (s, f)
  55 #endif
  56
  57 /*
  58  * Ops vector for TCP/IP based rpc service handle
  59  */
  60 static bool_t svctcp_recv (SVCXPRT *, struct rpc_msg *);
  61 static enum xprt_stat svctcp_stat (SVCXPRT *);
  62 static bool_t svctcp_getargs (SVCXPRT *, xdrproc_t, caddr_t);
  63 static bool_t svctcp_reply (SVCXPRT *, struct rpc_msg *);
  64 static bool_t svctcp_freeargs (SVCXPRT *, xdrproc_t, caddr_t);
  65 static void svctcp_destroy (SVCXPRT *);
  66
  67 static const struct xp_ops svctcp_op =
  68 {
  69   svctcp_recv,
  70   svctcp_stat,
  71   svctcp_getargs,
  72   svctcp_reply,
  73   svctcp_freeargs,
  74   svctcp_destroy
  75 };
  76
  77 /*
  78  * Ops vector for TCP/IP rendezvous handler
  79  */
  80 static bool_t rendezvous_request (SVCXPRT *, struct rpc_msg *);
  81 static enum xprt_stat rendezvous_stat (SVCXPRT *);
  82
  83 static const struct xp_ops svctcp_rendezvous_op =
  84 {
  85   rendezvous_request,
  86   rendezvous_stat,
  87   (bool_t (*) (SVCXPRT *, xdrproc_t, caddr_t)) abort,
  88   (bool_t (*) (SVCXPRT *, struct rpc_msg *)) abort,
  89   (bool_t (*) (SVCXPRT *, xdrproc_t, caddr_t)) abort,
  90   svctcp_destroy
  91 };
  92
  93 static int readtcp (char*, char *, int);
  94 static int writetcp (char *, char *, int);
  95 static SVCXPRT *makefd_xprt (int, u_int, u_int) internal_function;
  96
  97 struct tcp_rendezvous
  98   {                             /* kept in xprt->xp_p1 */
  99     u_int sendsize;
 100     u_int recvsize;
 101   };
 102
 103 struct tcp_conn
 104   {                             /* kept in xprt->xp_p1 */
 105     enum xprt_stat strm_stat;
 106     u_long x_id;
 107     XDR xdrs;
 108     char verf_body[MAX_AUTH_BYTES];
 109   };
 110
 111 /*
 112  * Usage:
 113  *      xprt = svctcp_create(sock, send_buf_size, recv_buf_size);
 114  *
 115  * Creates, registers, and returns a (rpc) tcp based transporter.
 116  * Once *xprt is initialized, it is registered as a transporter
 117  * see (svc.h, xprt_register).  This routine returns
 118  * a NULL if a problem occurred.
 119  *
 120  * If sock<0 then a socket is created, else sock is used.
 121  * If the socket, sock is not bound to a port then svctcp_create
 122  * binds it to an arbitrary port.  The routine then starts a tcp
 123  * listener on the socket's associated port.  In any (successful) case,
 124  * xprt->xp_sock is the registered socket number and xprt->xp_port is the
 125  * associated port number.
 126  *
 127  * Since tcp streams do buffered io similar to stdio, the caller can specify
 128  * how big the send and receive buffers are via the second and third parms;
 129  * 0 => use the system default.
 130  */
 131 SVCXPRT *
 132 svctcp_create (int sock, u_int sendsize, u_int recvsize)
 133 {
 134   bool_t madesock = FALSE;
 135   SVCXPRT *xprt;
 136   struct tcp_rendezvous *r;
 137   struct sockaddr_in addr;
 138   socklen_t len = sizeof (struct sockaddr_in);
 139
 140   if (sock == RPC_ANYSOCK)
 141     {
 142       if ((sock = __socket (AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0)
 143         {
 144           perror (_("svc_tcp.c - tcp socket creation problem"));
 145           return (SVCXPRT *) NULL;
 146         }
 147       madesock = TRUE;
 148     }
 149   __bzero ((char *) &addr, sizeof (addr));
 150   addr.sin_family = AF_INET;
 151   if (bindresvport (sock, &addr))
 152     {
 153       addr.sin_port = 0;
 154       (void) bind (sock, (struct sockaddr *) &addr, len);
 155     }
 156   if ((getsockname (sock, (struct sockaddr *) &addr, &len) != 0) ||
 157       (listen (sock, 2) != 0))
 158     {
 159       perror (_("svc_tcp.c - cannot getsockname or listen"));
 160       if (madesock)
 161         (void) __close (sock);
 162       return (SVCXPRT *) NULL;
 163     }
 164   r = (struct tcp_rendezvous *) mem_alloc (sizeof (*r));
 165   if (r == NULL)
 166     {
 167       (void) fputs (_("svctcp_create: out of memory\n"), stderr);
 168       return NULL;
 169     }
 170   r->sendsize = sendsize;
 171   r->recvsize = recvsize;
 172   xprt = (SVCXPRT *) mem_alloc (sizeof (SVCXPRT));
 173   if (xprt == NULL)
 174     {
 175       (void) fputs (_("svctcp_create: out of memory\n"), stderr);
 176       return NULL;
 177     }
 178   xprt->xp_p2 = NULL;
 179   xprt->xp_p1 = (caddr_t) r;
 180   xprt->xp_verf = _null_auth;
 181   xprt->xp_ops = &svctcp_rendezvous_op;
 182   xprt->xp_port = ntohs (addr.sin_port);
 183   xprt->xp_sock = sock;
 184   xprt_register (xprt);
 185   return xprt;
 186 }
 187
 188 /*
 189  * Like svtcp_create(), except the routine takes any *open* UNIX file
 190  * descriptor as its first input.
 191  */
 192 SVCXPRT *
 193 svcfd_create (int fd, u_int sendsize, u_int recvsize)
 194 {
 195   return makefd_xprt (fd, sendsize, recvsize);
 196 }
 197
 198 static SVCXPRT *
 199 internal_function
 200 makefd_xprt (int fd, u_int sendsize, u_int recvsize)
 201 {
 202   SVCXPRT *xprt;
 203   struct tcp_conn *cd;
 204
 205   xprt = (SVCXPRT *) mem_alloc (sizeof (SVCXPRT));
 206   if (xprt == (SVCXPRT *) NULL)
 207     {
 208       (void) fputs (_("svc_tcp: makefd_xprt: out of memory\n"), stderr);
 209       goto done;
 210     }
 211   cd = (struct tcp_conn *) mem_alloc (sizeof (struct tcp_conn));
 212   if (cd == (struct tcp_conn *) NULL)
 213     {
 214       (void) fputs (_("svc_tcp: makefd_xprt: out of memory\n"), stderr);
 215       mem_free ((char *) xprt, sizeof (SVCXPRT));
 216       xprt = (SVCXPRT *) NULL;
 217       goto done;
 218     }
 219   cd->strm_stat = XPRT_IDLE;
 220   xdrrec_create (&(cd->xdrs), sendsize, recvsize,
 221                  (caddr_t) xprt, readtcp, writetcp);
 222   xprt->xp_p2 = NULL;
 223   xprt->xp_p1 = (caddr_t) cd;
 224   xprt->xp_verf.oa_base = cd->verf_body;
 225   xprt->xp_addrlen = 0;
 226   xprt->xp_ops = &svctcp_op;    /* truly deals with calls */
 227   xprt->xp_port = 0;            /* this is a connection, not a rendezvouser */
 228   xprt->xp_sock = fd;
 229   xprt_register (xprt);
 230 done:
 231   return xprt;
 232 }
 233
 234 static bool_t
 235 rendezvous_request (SVCXPRT *xprt, struct rpc_msg *errmsg)
 236 {
 237   int sock;
 238   struct tcp_rendezvous *r;
 239   struct sockaddr_in addr;
 240   socklen_t len;
 241
 242   r = (struct tcp_rendezvous *) xprt->xp_p1;
 243 again:
 244   len = sizeof (struct sockaddr_in);
 245   if ((sock = accept (xprt->xp_sock, (struct sockaddr *) &addr, &len)) < 0)
 246     {
 247       if (errno == EINTR)
 248         goto again;
 249       return FALSE;
 250     }
 251   /*
 252    * make a new transporter (re-uses xprt)
 253    */
 254   xprt = makefd_xprt (sock, r->sendsize, r->recvsize);
 255   xprt->xp_raddr = addr;
 256   xprt->xp_addrlen = len;
 257   return FALSE;         /* there is never an rpc msg to be processed */
 258 }
 259
 260 static enum xprt_stat
 261 rendezvous_stat (SVCXPRT *xprt)
 262 {
 263   return XPRT_IDLE;
 264 }
 265
 266 static void
 267 svctcp_destroy (SVCXPRT *xprt)
 268 {
 269   struct tcp_conn *cd = (struct tcp_conn *) xprt->xp_p1;
 270
 271   xprt_unregister (xprt);
 272   (void) __close (xprt->xp_sock);
 273   if (xprt->xp_port != 0)
 274     {
 275       /* a rendezvouser socket */
 276       xprt->xp_port = 0;
 277     }
 278   else
 279     {
 280       /* an actual connection socket */
 281       XDR_DESTROY (&(cd->xdrs));
 282     }
 283   mem_free ((caddr_t) cd, sizeof (struct tcp_conn));
 284   mem_free ((caddr_t) xprt, sizeof (SVCXPRT));
 285 }
 286
 287 /*
 288  * All read operations timeout after 35 seconds.
 289  * A timeout is fatal for the connection.
 290  */
 291 static struct timeval wait_per_try = {35, 0};
 292
 293 /*
 294  * reads data from the tcp connection.
 295  * any error is fatal and the connection is closed.
 296  * (And a read of zero bytes is a half closed stream => error.)
 297  *
 298  * Note: we have to be careful here not to allow ourselves to become
 299  * blocked too long in this routine.  While we're waiting for data from one
 300  * client, another client may be trying to connect.  To avoid this situation,
 301  * some code from svc_run() is transplanted here: the select() loop checks
 302  * all RPC descriptors including the one we want and calls svc_getreqset2()
 303  * to handle new requests if any are detected.
 304  */
 305 static int
 306 readtcp (char *xprtptr, char *buf, int len)
 307 {
 308   SVCXPRT *xprt = (SVCXPRT *)xprtptr;
 309   int sock = xprt->xp_sock;
 310 #ifdef FD_SETSIZE
 311   fd_set readfds;
 312 #else
 313   int mask = 1 << sock;
 314   int readfds;
 315 #endif /* def FD_SETSIZE */
 316   while (1)
 317     {
 318       struct timeval timeout = wait_per_try;
 319       readfds = svc_fdset;
 320 #ifdef FD_SETSIZE
 321       FD_SET (sock, &readfds);
 322 #else
 323       readfds |= (1 << sock);
 324 #endif /* def FD_SETSIZE */
 325       if (__select (_rpc_dtablesize (), &readfds, (fd_set *) NULL,
 326                     (fd_set *) NULL, &timeout) <= 0)
 327         {
 328           if (errno == EINTR)
 329             continue;
 330           goto fatal_err;
 331         }
 332
 333 #ifdef FD_SETSIZE
 334       if (FD_ISSET (sock, &readfds))
 335 #else
 336       if (readfds == mask)
 337 #endif /* def FD_SETSIZE */
 338         break;
 339
 340       svc_getreqset (&readfds);
 341     }
 342
 343   if ((len = __read (sock, buf, len)) > 0)
 344     return len;
 345
 346 fatal_err:
 347   ((struct tcp_conn *) (xprt->xp_p1))->strm_stat = XPRT_DIED;
 348   return -1;
 349 }
 350
 351 /*
 352  * writes data to the tcp connection.
 353  * Any error is fatal and the connection is closed.
 354  */
 355 static int
 356 writetcp (char *xprtptr, char * buf, int len)
 357 {
 358   SVCXPRT *xprt = (SVCXPRT *)xprtptr;
 359   int i, cnt;
 360
 361   for (cnt = len; cnt > 0; cnt -= i, buf += i)
 362     {
 363       if ((i = __write (xprt->xp_sock, buf, cnt)) < 0)
 364         {
 365           ((struct tcp_conn *) (xprt->xp_p1))->strm_stat =
 366             XPRT_DIED;
 367           return (-1);
 368         }
 369     }
 370   return (len);
 371 }
 372
 373 static enum xprt_stat
 374 svctcp_stat (SVCXPRT *xprt)
 375 {
 376   struct tcp_conn *cd =
 377   (struct tcp_conn *) (xprt->xp_p1);
 378
 379   if (cd->strm_stat == XPRT_DIED)
 380     return (XPRT_DIED);
 381   if (!xdrrec_eof (&(cd->xdrs)))
 382     return (XPRT_MOREREQS);
 383   return (XPRT_IDLE);
 384 }
 385
 386 static bool_t
 387 svctcp_recv (xprt, msg)
 388      SVCXPRT *xprt;
 389      struct rpc_msg *msg;
 390 {
 391   struct tcp_conn *cd =
 392   (struct tcp_conn *) (xprt->xp_p1);
 393   XDR *xdrs = &(cd->xdrs);
 394
 395   xdrs->x_op = XDR_DECODE;
 396   (void) xdrrec_skiprecord (xdrs);
 397   if (xdr_callmsg (xdrs, msg))
 398     {
 399       cd->x_id = msg->rm_xid;
 400       return (TRUE);
 401     }
 402   cd->strm_stat = XPRT_DIED;    /* XXXX */
 403   return (FALSE);
 404 }
 405
 406 static bool_t
 407 svctcp_getargs (xprt, xdr_args, args_ptr)
 408      SVCXPRT *xprt;
 409      xdrproc_t xdr_args;
 410      caddr_t args_ptr;
 411 {
 412
 413   return ((*xdr_args) (&(((struct tcp_conn *) (xprt->xp_p1))->xdrs), args_ptr));
 414 }
 415
 416 static bool_t
 417 svctcp_freeargs (xprt, xdr_args, args_ptr)
 418      SVCXPRT *xprt;
 419      xdrproc_t xdr_args;
 420      caddr_t args_ptr;
 421 {
 422   XDR *xdrs =
 423   &(((struct tcp_conn *) (xprt->xp_p1))->xdrs);
 424
 425   xdrs->x_op = XDR_FREE;
 426   return ((*xdr_args) (xdrs, args_ptr));
 427 }
 428
 429 static bool_t
 430 svctcp_reply (xprt, msg)
 431      SVCXPRT *xprt;
 432      struct rpc_msg *msg;
 433 {
 434   struct tcp_conn *cd =
 435   (struct tcp_conn *) (xprt->xp_p1);
 436   XDR *xdrs = &(cd->xdrs);
 437   bool_t stat;
 438
 439   xdrs->x_op = XDR_ENCODE;
 440   msg->rm_xid = cd->x_id;
 441   stat = xdr_replymsg (xdrs, msg);
 442   (void) xdrrec_endofrecord (xdrs, TRUE);
 443   return (stat);
 444 }