nis.subproj/yp_bind.c

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Portions Copyright (c) 1999 Apple Computer, Inc.  All Rights
   7  * Reserved.  This file contains Original Code and/or Modifications of
   8  * Original Code as defined in and that are subject to the Apple Public
   9  * Source License Version 1.1 (the "License").  You may not use this file
  10  * except in compliance with the License.  Please obtain a copy of the
  11  * License at http://www.apple.com/publicsource and read it before using
  12  * this file.
  13  *
  14  * The Original Code and all software distributed under the License are
  15  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  16  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  17  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE OR NON- INFRINGEMENT.  Please see the
  19  * License for the specific language governing rights and limitations
  20  * under the License.
  21  *
  22  * @APPLE_LICENSE_HEADER_END@
  23  */
  24 /*
  25  * Copyright (c) 1996 Theo de Raadt <deraadt@theos.com>
  26  * Copyright (c) 1992, 1993 Theo de Raadt <deraadt@theos.com>
  27  * All rights reserved.
  28  *
  29  * Redistribution and use in source and binary forms, with or without
  30  * modification, are permitted provided that the following conditions
  31  * are met:
  32  * 1. Redistributions of source code must retain the above copyright
  33  *    notice, this list of conditions and the following disclaimer.
  34  * 2. Redistributions in binary form must reproduce the above copyright
  35  *    notice, this list of conditions and the following disclaimer in the
  36  *    documentation and/or other materials provided with the distribution.
  37  * 3. All advertising materials mentioning features or use of this software
  38  *    must display the following acknowledgement:
  39  *      This product includes software developed by Theo de Raadt.
  40  * 4. The name of the author may not be used to endorse or promote products
  41  *    derived from this software without specific prior written permission.
  42  *
  43  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
  44  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  45  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  46  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
  47  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  48  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  49  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  50  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  51  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  52  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  53  * SUCH DAMAGE.
  54  */
  55
  56 #if defined(LIBC_SCCS) && !defined(lint)
  57 static char *rcsid = "$OpenBSD: yp_bind.c,v 1.9 1997/04/29 21:25:20 deraadt Exp $";
  58 #endif /* LIBC_SCCS and not lint */
  59
  60 #include <sys/param.h>
  61 #include <sys/types.h>
  62 #include <sys/socket.h>
  63 #include <sys/file.h>
  64 #include <sys/uio.h>
  65 #include <errno.h>
  66 #include <stdio.h>
  67 #include <stdlib.h>
  68 #include <string.h>
  69 #include <unistd.h>
  70 #include <rpc/rpc.h>
  71 #include <rpc/xdr.h>
  72 #include <rpcsvc/yp.h>
  73 #include <rpcsvc/ypclnt.h>
  74 #include <notify.h>
  75 #include <pthread.h>
  76 #include "ypinternal.h"
  77
  78 extern int notify_register_plain(char *, int *);
  79
  80 struct dom_binding *_ypbindlist = NULL;
  81 char _yp_domain[MAXHOSTNAMELEN] = { '\0' };
  82
  83 int _yplib_timeout = 10;
  84
  85 int
  86 _yp_dobind(dom, ypdb)
  87         const char     *dom;
  88         struct dom_binding **ypdb;
  89 {
  90         static int      pid = -1;
  91         struct dom_binding *ysd, *ysd2;
  92         struct ypbind_resp ypbr;
  93         struct timeval  tv;
  94         struct sockaddr_in clnt_sin;
  95         struct ypbind_binding *bn;
  96         int             clnt_sock, fd, gpid;
  97         CLIENT         *client;
  98         int             new = 0, r, proto;
  99         int             count = 0;
 100         u_short         port;
 101         int status, notify_token;
 102         uint64_t abort;
 103         char *notify_name;
 104
 105         /*
 106          * test if YP is running or not
 107          */
 108         if ((fd = open(YPBINDLOCK, O_RDONLY)) == -1) return YPERR_YPBIND;
 109
 110         if (!((flock(fd, LOCK_EX | LOCK_NB) == -1) && (errno == EWOULDBLOCK)))
 111         {
 112                 close(fd);
 113                 return YPERR_YPBIND;
 114         }
 115
 116         close(fd);
 117
 118         gpid = getpid();
 119         if (!((pid == -1) || (pid == gpid)))
 120         {
 121                 ysd = _ypbindlist;
 122                 while (ysd)
 123                 {
 124                         if (ysd->dom_client) clnt_destroy(ysd->dom_client);
 125                         ysd2 = ysd->dom_pnext;
 126                         free(ysd);
 127                         ysd = ysd2;
 128                 }
 129
 130                 _ypbindlist = NULL;
 131         }
 132
 133         pid = gpid;
 134
 135         if (ypdb != NULL) *ypdb = NULL;
 136
 137         if ((dom == NULL) || (strlen(dom) == 0)) return YPERR_BADARGS;
 138
 139         for (ysd = _ypbindlist; ysd; ysd = ysd->dom_pnext)
 140         {
 141                 if (strcmp(dom, ysd->dom_domain) == 0) break;
 142         }
 143
 144         if (ysd == NULL)
 145         {
 146                 ysd = calloc(1, sizeof(struct dom_binding));
 147                 if (ysd == NULL) return YPERR_YPERR;
 148                 ysd->dom_socket = -1;
 149                 ysd->dom_vers = 0;
 150                 new = 1;
 151         }
 152
 153         /*
 154          * Get notification token
 155          * we use a self-notification token to allow a caller
 156          * to signal the thread doing this bind call to quit.
 157          */
 158         notify_name = NULL;
 159         notify_token = -1;
 160
 161         asprintf(&notify_name, "self.thread.%lu", (unsigned long)pthread_self());
 162         if (notify_name != NULL)
 163         {
 164                 status = notify_register_plain(notify_name, &notify_token);
 165                 free(notify_name);
 166         }
 167
 168 again:
 169         if (notify_token != -1)
 170         {
 171                 abort = 0;
 172                 status = notify_get_state(notify_token, &abort);
 173                 if (abort == ThreadStateExitRequested)
 174                 {
 175                         if (new) free(ysd);
 176                         notify_cancel(notify_token);
 177                         return YPERR_YPBIND;
 178                 }
 179         }
 180
 181         proto = YP_BIND_UDP;
 182         if (ysd->dom_vers == YP_BIND_TCP) proto = YP_BIND_TCP;
 183
 184         if ((ysd->dom_vers == 0) || (ysd->dom_vers == YP_BIND_UDP) || (ysd->dom_vers == YP_BIND_TCP))
 185         {
 186                 memset(&clnt_sin, 0, sizeof clnt_sin);
 187                 clnt_sin.sin_len = sizeof(struct sockaddr_in);
 188                 clnt_sin.sin_family = AF_INET;
 189                 clnt_sin.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
 190
 191                 clnt_sock = RPC_ANYSOCK;
 192                 client = clnttcp_create(&clnt_sin, YPBINDPROG, YPBINDVERS, &clnt_sock, 0, 0);
 193                 if (client == NULL)
 194                 {
 195                         clnt_pcreateerror("clnttcp_create");
 196                         if (new) free(ysd);
 197                         if (notify_token != -1) notify_cancel(notify_token);
 198                         return YPERR_YPBIND;
 199                 }
 200
 201                 if ((ntohs(clnt_sin.sin_port) >= IPPORT_RESERVED) || (ntohs(clnt_sin.sin_port) == 20))
 202                 {
 203                         /*
 204                          * YP was not running, but someone has registered
 205                          * ypbind with portmap -- this simply means YP is
 206                          * not running.
 207                          */
 208                         clnt_destroy(client);
 209                         if (new) free(ysd);
 210                         if (notify_token != -1) notify_cancel(notify_token);
 211                         return YPERR_YPBIND;
 212                 }
 213
 214                 tv.tv_sec = _yplib_timeout;
 215                 tv.tv_usec = 0;
 216
 217                 r = clnt_call(client, YPBINDPROC_DOMAIN, (xdrproc_t)xdr_domainname, &dom, (xdrproc_t)xdr_ypbind_resp, &ypbr, tv);
 218                 if (r != RPC_SUCCESS)
 219                 {
 220                         if (new == 0 || count) fprintf(stderr, "YP server for domain %s not responding, still trying\n", dom);
 221                         count++;
 222                         clnt_destroy(client);
 223                         ysd->dom_vers = proto;
 224                         goto again;
 225                 }
 226
 227                 clnt_destroy(client);
 228
 229                 bn = &ypbr.ypbind_resp_u.ypbind_bindinfo;
 230                 memcpy(&port, &bn->ypbind_binding_port, sizeof port);
 231                 if ((ntohs(port) >= IPPORT_RESERVED) || (ntohs(port) == 20))
 232                 {
 233                         /*
 234                          * This is bogus -- the ypbind wants me to
 235                          * communicate to an insecure ypserv.  We are
 236                          * within rights to syslog this as an attack,
 237                          * but for now we'll simply ignore it; real YP
 238                          * is obviously not running.
 239                          */
 240                         if (new) free(ysd);
 241                         if (notify_token != -1) notify_cancel(notify_token);
 242                         return YPERR_YPBIND;
 243                 }
 244
 245                 memset(&ysd->dom_server_addr, 0,  sizeof ysd->dom_server_addr);
 246                 ysd->dom_server_addr.sin_len = sizeof(struct sockaddr_in);
 247                 ysd->dom_server_addr.sin_family = AF_INET;
 248                 memcpy(&ysd->dom_server_addr.sin_port, &bn->ypbind_binding_port, sizeof(ysd->dom_server_addr.sin_port));
 249                 memcpy(&ysd->dom_server_addr.sin_addr.s_addr, &bn->ypbind_binding_addr, sizeof(ysd->dom_server_addr.sin_addr.s_addr));
 250                 ysd->dom_server_port = ysd->dom_server_addr.sin_port;
 251                 ysd->dom_vers = YPVERS;
 252                 strncpy(ysd->dom_domain, dom, sizeof ysd->dom_domain-1);
 253                 ysd->dom_domain[sizeof ysd->dom_domain-1] = '\0';
 254         }
 255
 256         tv.tv_sec = _yplib_timeout / 2;
 257         tv.tv_usec = 0;
 258
 259         if (ysd->dom_client) clnt_destroy(ysd->dom_client);
 260         ysd->dom_socket = RPC_ANYSOCK;
 261
 262         if (proto == YP_BIND_UDP) ysd->dom_client = clntudp_create(&ysd->dom_server_addr, YPPROG, YPVERS, tv, &ysd->dom_socket);
 263         else ysd->dom_client = clnttcp_create(&ysd->dom_server_addr, YPPROG, YPVERS, &ysd->dom_socket, 0, 0);
 264
 265         if (ysd->dom_client == NULL)
 266         {
 267                 if (proto == YP_BIND_UDP) clnt_pcreateerror("clntudp_create");
 268                 else clnt_pcreateerror("clnttcp_create");
 269                 ysd->dom_vers = proto;
 270                 goto again;
 271         }
 272
 273         if (notify_token != -1) notify_cancel(notify_token);
 274
 275         if (fcntl(ysd->dom_socket, F_SETFD, 1) == -1)
 276                 perror("fcntl: F_SETFD");
 277
 278         if (new != 0)
 279         {
 280                 ysd->dom_pnext = _ypbindlist;
 281                 _ypbindlist = ysd;
 282         }
 283
 284         if (ypdb != NULL) *ypdb = ysd;
 285         return 0;
 286 }
 287
 288 void
 289 _yp_unbind(ypb)
 290         struct dom_binding *ypb;
 291 {
 292         if (ypb->dom_client) clnt_destroy(ypb->dom_client);
 293         ypb->dom_client = NULL;
 294         ypb->dom_socket = -1;
 295 }
 296
 297 int
 298 yp_bind(dom)
 299         const char     *dom;
 300 {
 301         return _yp_dobind(dom, NULL);
 302 }
 303
 304 void
 305 yp_unbind(dom)
 306         const char     *dom;
 307 {
 308         struct dom_binding *ypb, *ypbp;
 309
 310         ypbp = NULL;
 311         for (ypb = _ypbindlist; ypb; ypb = ypb->dom_pnext) {
 312                 if (strcmp(dom, ypb->dom_domain) == 0) {
 313                         if (ypb->dom_client) clnt_destroy(ypb->dom_client);
 314                         if (ypbp)
 315                                 ypbp->dom_pnext = ypb->dom_pnext;
 316                         else
 317                                 _ypbindlist = ypb->dom_pnext;
 318                         free(ypb);
 319                         return;
 320                 }
 321                 ypbp = ypb;
 322         }
 323 }