libc/inet/rpc/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 0
  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_private.h"
  48 #include <sys/socket.h>
  49 #include <sys/poll.h>
  50 #include <errno.h>
  51 #include <stdlib.h>
  52
  53 /*
  54  * Ops vector for TCP/IP based rpc service handle
  55  */
  56 static bool_t svctcp_recv (SVCXPRT *, struct rpc_msg *);
  57 static enum xprt_stat svctcp_stat (SVCXPRT *);
  58 static bool_t svctcp_getargs (SVCXPRT *, xdrproc_t, caddr_t);
  59 static bool_t svctcp_reply (SVCXPRT *, struct rpc_msg *);
  60 static bool_t svctcp_freeargs (SVCXPRT *, xdrproc_t, caddr_t);
  61 static void svctcp_destroy (SVCXPRT *);
  62
  63 static const struct xp_ops svctcp_op =
  64 {
  65   svctcp_recv,
  66   svctcp_stat,
  67   svctcp_getargs,
  68   svctcp_reply,
  69   svctcp_freeargs,
  70   svctcp_destroy
  71 };
  72
  73 /*
  74  * Ops vector for TCP/IP rendezvous handler
  75  */
  76 static bool_t rendezvous_request (SVCXPRT *, struct rpc_msg *);
  77 static enum xprt_stat rendezvous_stat (SVCXPRT *);
  78 static void svctcp_rendezvous_abort (void) attribute_noreturn;
  79
  80 /* This function makes sure abort() relocation goes through PLT
  81    and thus can be lazy bound.  */
  82 static void
  83 svctcp_rendezvous_abort (void)
  84 {
  85   abort ();
  86 };
  87
  88 static const struct xp_ops svctcp_rendezvous_op =
  89 {
  90   rendezvous_request,
  91   rendezvous_stat,
  92   (bool_t (*) (SVCXPRT *, xdrproc_t, caddr_t)) svctcp_rendezvous_abort,
  93   (bool_t (*) (SVCXPRT *, struct rpc_msg *)) svctcp_rendezvous_abort,
  94   (bool_t (*) (SVCXPRT *, xdrproc_t, caddr_t)) svctcp_rendezvous_abort,
  95   svctcp_destroy
  96 };
  97
  98 static int readtcp (char*, char *, int);
  99 static int writetcp (char *, char *, int);
 100 static SVCXPRT *makefd_xprt (int, u_int, u_int) internal_function;
 101
 102 struct tcp_rendezvous
 103   {                             /* kept in xprt->xp_p1 */
 104     u_int sendsize;
 105     u_int recvsize;
 106   };
 107
 108 struct tcp_conn
 109   {                             /* kept in xprt->xp_p1 */
 110     enum xprt_stat strm_stat;
 111     u_long x_id;
 112     XDR xdrs;
 113     char verf_body[MAX_AUTH_BYTES];
 114   };
 115
 116 /*
 117  * Usage:
 118  *      xprt = svctcp_create(sock, send_buf_size, recv_buf_size);
 119  *
 120  * Creates, registers, and returns a (rpc) tcp based transporter.
 121  * Once *xprt is initialized, it is registered as a transporter
 122  * see (svc.h, xprt_register).  This routine returns
 123  * a NULL if a problem occurred.
 124  *
 125  * If sock<0 then a socket is created, else sock is used.
 126  * If the socket, sock is not bound to a port then svctcp_create
 127  * binds it to an arbitrary port.  The routine then starts a tcp
 128  * listener on the socket's associated port.  In any (successful) case,
 129  * xprt->xp_sock is the registered socket number and xprt->xp_port is the
 130  * associated port number.
 131  *
 132  * Since tcp streams do buffered io similar to stdio, the caller can specify
 133  * how big the send and receive buffers are via the second and third parms;
 134  * 0 => use the system default.
 135  */
 136 SVCXPRT *
 137 svctcp_create (int sock, u_int sendsize, u_int recvsize)
 138 {
 139   bool_t madesock = FALSE;
 140   SVCXPRT *xprt;
 141   struct tcp_rendezvous *r;
 142   struct sockaddr_in addr;
 143   socklen_t len = sizeof (struct sockaddr_in);
 144
 145   if (sock == RPC_ANYSOCK)
 146     {
 147       if ((sock = socket (AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0)
 148         {
 149           perror ("svc_tcp.c - tcp socket creation problem");
 150           return (SVCXPRT *) NULL;
 151         }
 152       madesock = TRUE;
 153     }
 154   memset ((char *) &addr, 0, sizeof (addr));
 155   addr.sin_family = AF_INET;
 156   if (bindresvport (sock, &addr))
 157     {
 158       addr.sin_port = 0;
 159       (void) bind (sock, (struct sockaddr *) &addr, len);
 160     }
 161   if ((getsockname (sock, (struct sockaddr *) &addr, &len) != 0) ||
 162       (listen (sock, 2) != 0))
 163     {
 164       perror ("svc_tcp.c - cannot getsockname or listen");
 165       if (madesock)
 166         (void) close (sock);
 167       return (SVCXPRT *) NULL;
 168     }
 169   r = (struct tcp_rendezvous *) mem_alloc (sizeof (*r));
 170   xprt = (SVCXPRT *) mem_alloc (sizeof (SVCXPRT));
 171   if (r == NULL || xprt == NULL)
 172     {
 173       (void) fputs ("svctcp_create: out of memory\n", stderr);
 174       mem_free (r, sizeof (*r));
 175       mem_free (xprt, sizeof (SVCXPRT));
 176       return NULL;
 177     }
 178   r->sendsize = sendsize;
 179   r->recvsize = recvsize;
 180   xprt->xp_p2 = NULL;
 181   xprt->xp_p1 = (caddr_t) r;
 182   xprt->xp_verf = _null_auth;
 183   xprt->xp_ops = &svctcp_rendezvous_op;
 184   xprt->xp_port = ntohs (addr.sin_port);
 185   xprt->xp_sock = sock;
 186   xprt_register (xprt);
 187   return xprt;
 188 }
 189
 190 /*
 191  * Like svtcp_create(), except the routine takes any *open* UNIX file
 192  * descriptor as its first input.
 193  */
 194 SVCXPRT *
 195 svcfd_create (int fd, u_int sendsize, u_int recvsize);
 196 SVCXPRT *
 197 svcfd_create (int fd, u_int sendsize, u_int recvsize)
 198 {
 199   return makefd_xprt (fd, sendsize, recvsize);
 200 }
 201
 202 static SVCXPRT *
 203 internal_function
 204 makefd_xprt (int fd, u_int sendsize, u_int recvsize)
 205 {
 206   SVCXPRT *xprt;
 207   struct tcp_conn *cd;
 208
 209   xprt = (SVCXPRT *) mem_alloc (sizeof (SVCXPRT));
 210   cd = (struct tcp_conn *) mem_alloc (sizeof (struct tcp_conn));
 211   if (xprt == (SVCXPRT *) NULL || cd == NULL)
 212     {
 213       (void) fputs ("svc_tcp: makefd_xprt: out of memory\n", stderr);
 214       mem_free (xprt, sizeof (SVCXPRT));
 215       mem_free (cd, sizeof (struct tcp_conn));
 216       return NULL;
 217     }
 218   cd->strm_stat = XPRT_IDLE;
 219   xdrrec_create (&(cd->xdrs), sendsize, recvsize,
 220                  (caddr_t) xprt, readtcp, writetcp);
 221   xprt->xp_p2 = NULL;
 222   xprt->xp_p1 = (caddr_t) cd;
 223   xprt->xp_verf.oa_base = cd->verf_body;
 224   xprt->xp_addrlen = 0;
 225   xprt->xp_ops = &svctcp_op;    /* truly deals with calls */
 226   xprt->xp_port = 0;            /* this is a connection, not a rendezvouser */
 227   xprt->xp_sock = fd;
 228   xprt_register (xprt);
 229   return xprt;
 230 }
 231
 232 static bool_t
 233 rendezvous_request (SVCXPRT *xprt, struct rpc_msg *errmsg attribute_unused)
 234 {
 235   int sock;
 236   struct tcp_rendezvous *r;
 237   struct sockaddr_in addr;
 238   socklen_t len;
 239
 240   r = (struct tcp_rendezvous *) xprt->xp_p1;
 241 again:
 242   len = sizeof (struct sockaddr_in);
 243   if ((sock = accept (xprt->xp_sock, (struct sockaddr *) &addr, &len)) < 0)
 244     {
 245       if (errno == EINTR)
 246         goto again;
 247       return FALSE;
 248     }
 249   /*
 250    * make a new transporter (re-uses xprt)
 251    */
 252   xprt = makefd_xprt (sock, r->sendsize, r->recvsize);
 253   memcpy (&xprt->xp_raddr, &addr, sizeof (addr));
 254   xprt->xp_addrlen = len;
 255   return FALSE;         /* there is never an rpc msg to be processed */
 256 }
 257
 258 static enum xprt_stat
 259 rendezvous_stat (SVCXPRT *xprt attribute_unused)
 260 {
 261   return XPRT_IDLE;
 262 }
 263
 264 static void
 265 svctcp_destroy (SVCXPRT *xprt)
 266 {
 267   struct tcp_conn *cd = (struct tcp_conn *) xprt->xp_p1;
 268
 269   xprt_unregister (xprt);
 270   (void) close (xprt->xp_sock);
 271   if (xprt->xp_port != 0)
 272     {
 273       /* a rendezvouser socket */
 274       xprt->xp_port = 0;
 275     }
 276   else
 277     {
 278       /* an actual connection socket */
 279       XDR_DESTROY (&(cd->xdrs));
 280     }
 281   mem_free ((caddr_t) cd, sizeof (struct tcp_conn));
 282   mem_free ((caddr_t) xprt, sizeof (SVCXPRT));
 283 }
 284
 285
 286 /*
 287  * reads data from the tcp connection.
 288  * any error is fatal and the connection is closed.
 289  * (And a read of zero bytes is a half closed stream => error.)
 290  */
 291 static int
 292 readtcp (char *xprtptr, char *buf, int len)
 293 {
 294   SVCXPRT *xprt = (SVCXPRT *)xprtptr;
 295   int sock = xprt->xp_sock;
 296   int milliseconds = 35 * 1000;
 297   struct pollfd pollfd;
 298
 299   do
 300     {
 301       pollfd.fd = sock;
 302       pollfd.events = POLLIN;
 303       switch (poll (&pollfd, 1, milliseconds))
 304         {
 305         case -1:
 306           if (errno == EINTR)
 307             continue;
 308           /*FALLTHROUGH*/
 309         case 0:
 310           goto fatal_err;
 311         default:
 312           if ((pollfd.revents & POLLERR) || (pollfd.revents & POLLHUP)
 313               || (pollfd.revents & POLLNVAL))
 314             goto fatal_err;
 315           break;
 316         }
 317     }
 318   while ((pollfd.revents & POLLIN) == 0);
 319
 320   if ((len = read (sock, buf, len)) > 0)
 321     return len;
 322
 323  fatal_err:
 324   ((struct tcp_conn *) (xprt->xp_p1))->strm_stat = XPRT_DIED;
 325   return -1;
 326 }
 327
 328 /*
 329  * writes data to the tcp connection.
 330  * Any error is fatal and the connection is closed.
 331  */
 332 static int
 333 writetcp (char *xprtptr, char * buf, int len)
 334 {
 335   SVCXPRT *xprt = (SVCXPRT *)xprtptr;
 336   int i, cnt;
 337
 338   for (cnt = len; cnt > 0; cnt -= i, buf += i)
 339     {
 340       if ((i = write (xprt->xp_sock, buf, cnt)) < 0)
 341         {
 342           ((struct tcp_conn *) (xprt->xp_p1))->strm_stat = XPRT_DIED;
 343           return -1;
 344         }
 345     }
 346   return len;
 347 }
 348
 349 static enum xprt_stat
 350 svctcp_stat (SVCXPRT *xprt)
 351 {
 352   struct tcp_conn *cd =
 353   (struct tcp_conn *) (xprt->xp_p1);
 354
 355   if (cd->strm_stat == XPRT_DIED)
 356     return XPRT_DIED;
 357   if (!xdrrec_eof (&(cd->xdrs)))
 358     return XPRT_MOREREQS;
 359   return XPRT_IDLE;
 360 }
 361
 362 static bool_t
 363 svctcp_recv (SVCXPRT *xprt, struct rpc_msg *msg)
 364 {
 365   struct tcp_conn *cd = (struct tcp_conn *) (xprt->xp_p1);
 366   XDR *xdrs = &(cd->xdrs);
 367
 368   xdrs->x_op = XDR_DECODE;
 369   (void) xdrrec_skiprecord (xdrs);
 370   if (xdr_callmsg (xdrs, msg))
 371     {
 372       cd->x_id = msg->rm_xid;
 373       return TRUE;
 374     }
 375   cd->strm_stat = XPRT_DIED;    /* XXXX */
 376   return FALSE;
 377 }
 378
 379 static bool_t
 380 svctcp_getargs (SVCXPRT *xprt, xdrproc_t xdr_args, caddr_t args_ptr)
 381 {
 382   return ((*xdr_args) (&(((struct tcp_conn *)
 383                           (xprt->xp_p1))->xdrs), args_ptr));
 384 }
 385
 386 static bool_t
 387 svctcp_freeargs (SVCXPRT *xprt, xdrproc_t xdr_args, caddr_t args_ptr)
 388 {
 389   XDR *xdrs = &(((struct tcp_conn *) (xprt->xp_p1))->xdrs);
 390
 391   xdrs->x_op = XDR_FREE;
 392   return ((*xdr_args) (xdrs, args_ptr));
 393 }
 394
 395 static bool_t
 396 svctcp_reply (SVCXPRT *xprt, struct rpc_msg *msg)
 397 {
 398   struct tcp_conn *cd = (struct tcp_conn *) (xprt->xp_p1);
 399   XDR *xdrs = &(cd->xdrs);
 400   bool_t stat;
 401
 402   xdrs->x_op = XDR_ENCODE;
 403   msg->rm_xid = cd->x_id;
 404   stat = xdr_replymsg (xdrs, msg);
 405   (void) xdrrec_endofrecord (xdrs, TRUE);
 406   return stat;
 407 }