usr.sbin/rpcbind/check_bound.c

   1 /*      $NetBSD: check_bound.c,v 1.2 2000/06/22 08:09:26 fvdl Exp $     */
   2 /*      $FreeBSD$ */
   3
   4 /*-
   5  * Copyright (c) 2009, Sun Microsystems, Inc.
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions are met:
  10  * - Redistributions of source code must retain the above copyright notice,
  11  *   this list of conditions and the following disclaimer.
  12  * - Redistributions in binary form must reproduce the above copyright notice,
  13  *   this list of conditions and the following disclaimer in the documentation
  14  *   and/or other materials provided with the distribution.
  15  * - Neither the name of Sun Microsystems, Inc. nor the names of its
  16  *   contributors may be used to endorse or promote products derived
  17  *   from this software without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  20  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
  23  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  29  * POSSIBILITY OF SUCH DAMAGE.
  30  */
  31 /*
  32  * Copyright (c) 1986 - 1991 by Sun Microsystems, Inc.
  33  */
  34
  35 /* #ident       "@(#)check_bound.c      1.15    93/07/05 SMI" */
  36
  37 #if 0
  38 #ifndef lint
  39 static  char sccsid[] = "@(#)check_bound.c 1.11 89/04/21 Copyr 1989 Sun Micro";
  40 #endif
  41 #endif
  42
  43 /*
  44  * check_bound.c
  45  * Checks to see whether the program is still bound to the
  46  * claimed address and returns the universal merged address
  47  *
  48  */
  49
  50 #include <sys/types.h>
  51 #include <sys/socket.h>
  52 #include <rpc/rpc.h>
  53 #include <rpc/svc_dg.h>
  54 #include <stdio.h>
  55 #include <netconfig.h>
  56 #include <syslog.h>
  57 #include <string.h>
  58 #include <unistd.h>
  59 #include <stdlib.h>
  60
  61 #include "rpcbind.h"
  62
  63 struct fdlist {
  64         int fd;
  65         struct netconfig *nconf;
  66         struct fdlist *next;
  67         int check_binding;
  68 };
  69
  70 static struct fdlist *fdhead;   /* Link list of the check fd's */
  71 static struct fdlist *fdtail;
  72 static char *nullstring = "";
  73
  74 static bool_t check_bound(struct fdlist *, char *uaddr);
  75
  76 /*
  77  * Returns 1 if the given address is bound for the given addr & transport
  78  * For all error cases, we assume that the address is bound
  79  * Returns 0 for success.
  80  */
  81 static bool_t
  82 check_bound(struct fdlist *fdl, char *uaddr)
  83 {
  84         int fd;
  85         struct netbuf *na;
  86         int ans;
  87
  88         if (fdl->check_binding == FALSE)
  89                 return (TRUE);
  90
  91         na = uaddr2taddr(fdl->nconf, uaddr);
  92         if (!na)
  93                 return (TRUE); /* punt, should never happen */
  94
  95         fd = __rpc_nconf2fd(fdl->nconf);
  96         if (fd < 0) {
  97                 free(na->buf);
  98                 free(na);
  99                 return (TRUE);
 100         }
 101
 102         ans = bind(fd, (struct sockaddr *)na->buf, na->len);
 103
 104         close(fd);
 105         free(na->buf);
 106         free(na);
 107
 108         return (ans == 0 ? FALSE : TRUE);
 109 }
 110
 111 int
 112 add_bndlist(struct netconfig *nconf, struct netbuf *baddr __unused)
 113 {
 114         struct fdlist *fdl;
 115         struct netconfig *newnconf;
 116
 117         newnconf = getnetconfigent(nconf->nc_netid);
 118         if (newnconf == NULL)
 119                 return (-1);
 120         fdl = malloc(sizeof (struct fdlist));
 121         if (fdl == NULL) {
 122                 freenetconfigent(newnconf);
 123                 syslog(LOG_ERR, "no memory!");
 124                 return (-1);
 125         }
 126         fdl->nconf = newnconf;
 127         fdl->next = NULL;
 128         if (fdhead == NULL) {
 129                 fdhead = fdl;
 130                 fdtail = fdl;
 131         } else {
 132                 fdtail->next = fdl;
 133                 fdtail = fdl;
 134         }
 135         /* XXX no bound checking for now */
 136         fdl->check_binding = FALSE;
 137
 138         return 0;
 139 }
 140
 141 bool_t
 142 is_bound(char *netid, char *uaddr)
 143 {
 144         struct fdlist *fdl;
 145
 146         for (fdl = fdhead; fdl; fdl = fdl->next)
 147                 if (strcmp(fdl->nconf->nc_netid, netid) == 0)
 148                         break;
 149         if (fdl == NULL)
 150                 return (TRUE);
 151         return (check_bound(fdl, uaddr));
 152 }
 153
 154 /*
 155  * Returns NULL if there was some system error.
 156  * Returns "" if the address was not bound, i.e the server crashed.
 157  * Returns the merged address otherwise.
 158  */
 159 char *
 160 mergeaddr(SVCXPRT *xprt, char *netid, char *uaddr, char *saddr)
 161 {
 162         struct fdlist *fdl;
 163         struct svc_dg_data *dg_data;
 164         char *c_uaddr, *s_uaddr, *m_uaddr, *allocated_uaddr = NULL;
 165
 166         for (fdl = fdhead; fdl; fdl = fdl->next)
 167                 if (strcmp(fdl->nconf->nc_netid, netid) == 0)
 168                         break;
 169         if (fdl == NULL)
 170                 return (NULL);
 171         if (check_bound(fdl, uaddr) == FALSE)
 172                 /* that server died */
 173                 return (nullstring);
 174         /*
 175          * Try to determine the local address on which the client contacted us,
 176          * so we can send a reply from the same address.  If it's unknown, then
 177          * try to determine which address the client used, and pick a nearby
 178          * local address.
 179          *
 180          * If saddr is not NULL, the remote client may have included the
 181          * address by which it contacted us.  Use that for the "client" uaddr,
 182          * otherwise use the info from the SVCXPRT.
 183          */
 184         dg_data = (struct svc_dg_data*)xprt->xp_p2;
 185         if (dg_data != NULL && dg_data->su_srcaddr.buf != NULL) {
 186                 c_uaddr = taddr2uaddr(fdl->nconf, &dg_data->su_srcaddr);
 187                 allocated_uaddr = c_uaddr;
 188         }
 189         else if (saddr != NULL) {
 190                 c_uaddr = saddr;
 191         } else {
 192                 c_uaddr = taddr2uaddr(fdl->nconf, svc_getrpccaller(xprt));
 193                 allocated_uaddr = c_uaddr;
 194         }
 195         if (c_uaddr == NULL) {
 196                 syslog(LOG_ERR, "taddr2uaddr failed for %s",
 197                         fdl->nconf->nc_netid);
 198                 return (NULL);
 199         }
 200
 201 #ifdef ND_DEBUG
 202         if (debugging) {
 203                 if (saddr == NULL) {
 204                         fprintf(stderr, "mergeaddr: client uaddr = %s\n",
 205                             c_uaddr);
 206                 } else {
 207                         fprintf(stderr, "mergeaddr: contact uaddr = %s\n",
 208                             c_uaddr);
 209                 }
 210         }
 211 #endif
 212         s_uaddr = uaddr;
 213         /*
 214          * This is all we should need for IP 4 and 6
 215          */
 216         m_uaddr = addrmerge(svc_getrpccaller(xprt), s_uaddr, c_uaddr, netid);
 217 #ifdef ND_DEBUG
 218         if (debugging)
 219                 fprintf(stderr, "mergeaddr: uaddr = %s, merged uaddr = %s\n",
 220                                 uaddr, m_uaddr);
 221 #endif
 222         free(allocated_uaddr);
 223         return (m_uaddr);
 224 }
 225
 226 /*
 227  * Returns a netconf structure from its internal list.  This
 228  * structure should not be freed.
 229  */
 230 struct netconfig *
 231 rpcbind_get_conf(const char *netid)
 232 {
 233         struct fdlist *fdl;
 234
 235         for (fdl = fdhead; fdl; fdl = fdl->next)
 236                 if (strcmp(fdl->nconf->nc_netid, netid) == 0)
 237                         break;
 238         if (fdl == NULL)
 239                 return (NULL);
 240         return (fdl->nconf);
 241 }