sunrpc/svc_tcp.c

   1 /*
   2  * svc_tcp.c, Server side for TCP/IP based RPC.
   3  *
   4  * Copyright (C) 1984, Sun Microsystems, Inc.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions are
   8  * met:
   9  *
  10  *     * Redistributions of source code must retain the above copyright
  11  *       notice, this list of conditions and the following disclaimer.
  12  *     * Redistributions in binary form must reproduce the above
  13  *       copyright notice, this list of conditions and the following
  14  *       disclaimer in the documentation and/or other materials
  15  *       provided with the distribution.
  16  *     * Neither the name of Sun Microsystems, Inc. nor the names of its
  17  *       contributors may be used to endorse or promote products derived
  18  *       from this software without specific prior written permission.
  19  *
  20  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  21  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  22  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  23  *   FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
  24  *   COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
  25  *   INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  *   DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
  27  *   GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  28  *   INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  29  *   WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  30  *   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32  *
  33  * Actually implements two flavors of transporter -
  34  * a tcp rendezvouser (a listener and connection establisher)
  35  * and a record/tcp stream.
  36  */
  37
  38 #include <stdio.h>
  39 #include <unistd.h>
  40 #include <string.h>
  41 #include <libintl.h>
  42 #include <rpc/rpc.h>
  43 #include <sys/socket.h>
  44 #include <sys/poll.h>
  45 #include <errno.h>
  46 #include <stdlib.h>
  47
  48 #ifdef USE_IN_LIBIO
  49 # include <wchar.h>
  50 # include <libio/iolibio.h>
  51 #endif
  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   __bzero ((char *) &addr, 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, SOMAXCONN) != 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) __fxprintf (NULL, "%s: %s", __func__, _("out of memory\n"));
 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 {
 197   return makefd_xprt (fd, sendsize, recvsize);
 198 }
 199
 200 static SVCXPRT *
 201 internal_function
 202 makefd_xprt (int fd, u_int sendsize, u_int recvsize)
 203 {
 204   SVCXPRT *xprt;
 205   struct tcp_conn *cd;
 206
 207   xprt = (SVCXPRT *) mem_alloc (sizeof (SVCXPRT));
 208   cd = (struct tcp_conn *) mem_alloc (sizeof (struct tcp_conn));
 209   if (xprt == (SVCXPRT *) NULL || cd == NULL)
 210     {
 211       (void) __fxprintf (NULL, "%s: %s", "svc_tcp: makefd_xprt",
 212                          _("out of memory\n"));
 213       mem_free (xprt, sizeof (SVCXPRT));
 214       mem_free (cd, sizeof (struct tcp_conn));
 215       return NULL;
 216     }
 217   cd->strm_stat = XPRT_IDLE;
 218   INTUSE(xdrrec_create) (&(cd->xdrs), sendsize, recvsize,
 219                          (caddr_t) xprt, readtcp, writetcp);
 220   xprt->xp_p2 = NULL;
 221   xprt->xp_p1 = (caddr_t) cd;
 222   xprt->xp_verf.oa_base = cd->verf_body;
 223   xprt->xp_addrlen = 0;
 224   xprt->xp_ops = &svctcp_op;    /* truly deals with calls */
 225   xprt->xp_port = 0;            /* this is a connection, not a rendezvouser */
 226   xprt->xp_sock = fd;
 227   xprt_register (xprt);
 228   return xprt;
 229 }
 230
 231 static bool_t
 232 rendezvous_request (SVCXPRT *xprt, struct rpc_msg *errmsg)
 233 {
 234   int sock;
 235   struct tcp_rendezvous *r;
 236   struct sockaddr_in addr;
 237   socklen_t len;
 238
 239   r = (struct tcp_rendezvous *) xprt->xp_p1;
 240 again:
 241   len = sizeof (struct sockaddr_in);
 242   if ((sock = accept (xprt->xp_sock, (struct sockaddr *) &addr, &len)) < 0)
 243     {
 244       if (errno == EINTR)
 245         goto again;
 246       return FALSE;
 247     }
 248   /*
 249    * make a new transporter (re-uses xprt)
 250    */
 251   xprt = makefd_xprt (sock, r->sendsize, r->recvsize);
 252   memcpy (&xprt->xp_raddr, &addr, sizeof (addr));
 253   xprt->xp_addrlen = len;
 254   return FALSE;         /* there is never an rpc msg to be processed */
 255 }
 256
 257 static enum xprt_stat
 258 rendezvous_stat (SVCXPRT *xprt)
 259 {
 260   return XPRT_IDLE;
 261 }
 262
 263 static void
 264 svctcp_destroy (SVCXPRT *xprt)
 265 {
 266   struct tcp_conn *cd = (struct tcp_conn *) xprt->xp_p1;
 267
 268   xprt_unregister (xprt);
 269   (void) __close (xprt->xp_sock);
 270   if (xprt->xp_port != 0)
 271     {
 272       /* a rendezvouser socket */
 273       xprt->xp_port = 0;
 274     }
 275   else
 276     {
 277       /* an actual connection socket */
 278       XDR_DESTROY (&(cd->xdrs));
 279     }
 280   mem_free ((caddr_t) cd, sizeof (struct tcp_conn));
 281   mem_free ((caddr_t) xprt, sizeof (SVCXPRT));
 282 }
 283
 284
 285 /*
 286  * reads data from the tcp connection.
 287  * any error is fatal and the connection is closed.
 288  * (And a read of zero bytes is a half closed stream => error.)
 289  */
 290 static int
 291 readtcp (char *xprtptr, char *buf, int len)
 292 {
 293   SVCXPRT *xprt = (SVCXPRT *)xprtptr;
 294   int sock = xprt->xp_sock;
 295   int milliseconds = 35 * 1000;
 296   struct pollfd pollfd;
 297
 298   do
 299     {
 300       pollfd.fd = sock;
 301       pollfd.events = POLLIN;
 302       switch (__poll (&pollfd, 1, milliseconds))
 303         {
 304         case -1:
 305           if (errno == EINTR)
 306             continue;
 307           /*FALLTHROUGH*/
 308         case 0:
 309           goto fatal_err;
 310         default:
 311           if ((pollfd.revents & POLLERR) || (pollfd.revents & POLLHUP)
 312               || (pollfd.revents & POLLNVAL))
 313             goto fatal_err;
 314           break;
 315         }
 316     }
 317   while ((pollfd.revents & POLLIN) == 0);
 318
 319   if ((len = __read (sock, buf, len)) > 0)
 320     return len;
 321
 322  fatal_err:
 323   ((struct tcp_conn *) (xprt->xp_p1))->strm_stat = XPRT_DIED;
 324   return -1;
 325 }
 326
 327 /*
 328  * writes data to the tcp connection.
 329  * Any error is fatal and the connection is closed.
 330  */
 331 static int
 332 writetcp (char *xprtptr, char * buf, int len)
 333 {
 334   SVCXPRT *xprt = (SVCXPRT *)xprtptr;
 335   int i, cnt;
 336
 337   for (cnt = len; cnt > 0; cnt -= i, buf += i)
 338     {
 339       if ((i = __write (xprt->xp_sock, buf, cnt)) < 0)
 340         {
 341           ((struct tcp_conn *) (xprt->xp_p1))->strm_stat = XPRT_DIED;
 342           return -1;
 343         }
 344     }
 345   return len;
 346 }
 347
 348 static enum xprt_stat
 349 svctcp_stat (SVCXPRT *xprt)
 350 {
 351   struct tcp_conn *cd =
 352   (struct tcp_conn *) (xprt->xp_p1);
 353
 354   if (cd->strm_stat == XPRT_DIED)
 355     return XPRT_DIED;
 356   if (!INTUSE(xdrrec_eof) (&(cd->xdrs)))
 357     return XPRT_MOREREQS;
 358   return XPRT_IDLE;
 359 }
 360
 361 static bool_t
 362 svctcp_recv (SVCXPRT *xprt, struct rpc_msg *msg)
 363 {
 364   struct tcp_conn *cd = (struct tcp_conn *) (xprt->xp_p1);
 365   XDR *xdrs = &(cd->xdrs);
 366
 367   xdrs->x_op = XDR_DECODE;
 368   (void) INTUSE(xdrrec_skiprecord) (xdrs);
 369   if (INTUSE(xdr_callmsg) (xdrs, msg))
 370     {
 371       cd->x_id = msg->rm_xid;
 372       return TRUE;
 373     }
 374   cd->strm_stat = XPRT_DIED;    /* XXXX */
 375   return FALSE;
 376 }
 377
 378 static bool_t
 379 svctcp_getargs (SVCXPRT *xprt, xdrproc_t xdr_args, caddr_t args_ptr)
 380 {
 381   return ((*xdr_args) (&(((struct tcp_conn *)
 382                           (xprt->xp_p1))->xdrs), args_ptr));
 383 }
 384
 385 static bool_t
 386 svctcp_freeargs (SVCXPRT *xprt, xdrproc_t xdr_args, caddr_t args_ptr)
 387 {
 388   XDR *xdrs = &(((struct tcp_conn *) (xprt->xp_p1))->xdrs);
 389
 390   xdrs->x_op = XDR_FREE;
 391   return ((*xdr_args) (xdrs, args_ptr));
 392 }
 393
 394 static bool_t
 395 svctcp_reply (SVCXPRT *xprt, struct rpc_msg *msg)
 396 {
 397   struct tcp_conn *cd = (struct tcp_conn *) (xprt->xp_p1);
 398   XDR *xdrs = &(cd->xdrs);
 399   bool_t stat;
 400
 401   xdrs->x_op = XDR_ENCODE;
 402   msg->rm_xid = cd->x_id;
 403   stat = INTUSE(xdr_replymsg) (xdrs, msg);
 404   (void) INTUSE(xdrrec_endofrecord) (xdrs, TRUE);
 405   return stat;
 406 }