usr.sbin/rpcbind/check_bound.c

   1 /*
   2  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
   3  * unrestricted use provided that this legend is included on all tape
   4  * media and as a part of the software program in whole or part.  Users
   5  * may copy or modify Sun RPC without charge, but are not authorized
   6  * to license or distribute it to anyone else except as part of a product or
   7  * program developed by the user.
   8  *
   9  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
  10  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
  11  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
  12  *
  13  * Sun RPC is provided with no support and without any obligation on the
  14  * part of Sun Microsystems, Inc. to assist in its use, correction,
  15  * modification or enhancement.
  16  *
  17  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
  18  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
  19  * OR ANY PART THEREOF.
  20  *
  21  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
  22  * or profits or other special, indirect and consequential damages, even if
  23  * Sun has been advised of the possibility of such damages.
  24  *
  25  * Sun Microsystems, Inc.
  26  * 2550 Garcia Avenue
  27  * Mountain View, California  94043
  28  *
  29  * @(#)check_bound.c    1.15    93/07/05 SMI; 1.11 89/04/21 Copyr 1989 Sun Micro
  30  * $NetBSD: check_bound.c,v 1.2 2000/06/22 08:09:26 fvdl Exp $
  31  * $FreeBSD: src/usr.sbin/rpcbind/check_bound.c,v 1.5 2007/11/07 10:53:39 kevlo Exp $
  32  */
  33 /*
  34  * Copyright (c) 1986 - 1991 by Sun Microsystems, Inc.
  35  */
  36
  37 /*
  38  * check_bound.c
  39  * Checks to see whether the program is still bound to the
  40  * claimed address and returns the univeral merged address
  41  *
  42  */
  43
  44 #include <sys/types.h>
  45 #include <sys/socket.h>
  46 #include <rpc/rpc.h>
  47 #include <stdio.h>
  48 #include <netconfig.h>
  49 #include <syslog.h>
  50 #include <string.h>
  51 #include <unistd.h>
  52 #include <stdlib.h>
  53
  54 #include "rpcbind.h"
  55
  56 struct fdlist {
  57         int fd;
  58         struct netconfig *nconf;
  59         struct fdlist *next;
  60         int check_binding;
  61 };
  62
  63 static struct fdlist *fdhead;   /* Link list of the check fd's */
  64 static struct fdlist *fdtail;
  65 static char *nullstring = "";
  66
  67 static bool_t   check_bound(struct fdlist *, char *uaddr);
  68
  69 /*
  70  * Returns 1 if the given address is bound for the given addr & transport
  71  * For all error cases, we assume that the address is bound
  72  * Returns 0 for success.
  73  */
  74 static bool_t
  75 check_bound(struct fdlist *fdl, char *uaddr)
  76 {
  77         int fd;
  78         struct netbuf *na;
  79         int ans;
  80
  81         if (fdl->check_binding == FALSE)
  82                 return (TRUE);
  83
  84         na = uaddr2taddr(fdl->nconf, uaddr);
  85         if (!na)
  86                 return (TRUE); /* punt, should never happen */
  87
  88         fd = __rpc_nconf2fd(fdl->nconf);
  89         if (fd < 0) {
  90                 free(na->buf);
  91                 free(na);
  92                 return (TRUE);
  93         }
  94
  95         ans = bind(fd, (struct sockaddr *)na->buf, na->len);
  96
  97         close(fd);
  98         free(na->buf);
  99         free(na);
 100
 101         return (ans == 0 ? FALSE : TRUE);
 102 }
 103
 104 int
 105 add_bndlist(struct netconfig *nconf, struct netbuf *baddr __unused)
 106 {
 107         struct fdlist *fdl;
 108         struct netconfig *newnconf;
 109
 110         newnconf = getnetconfigent(nconf->nc_netid);
 111         if (newnconf == NULL)
 112                 return (-1);
 113         fdl = malloc(sizeof (struct fdlist));
 114         if (fdl == NULL) {
 115                 freenetconfigent(newnconf);
 116                 syslog(LOG_ERR, "no memory!");
 117                 return (-1);
 118         }
 119         fdl->nconf = newnconf;
 120         fdl->next = NULL;
 121         if (fdhead == NULL) {
 122                 fdhead = fdl;
 123                 fdtail = fdl;
 124         } else {
 125                 fdtail->next = fdl;
 126                 fdtail = fdl;
 127         }
 128         /* XXX no bound checking for now */
 129         fdl->check_binding = FALSE;
 130
 131         return 0;
 132 }
 133
 134 bool_t
 135 is_bound(char *netid, char *uaddr)
 136 {
 137         struct fdlist *fdl;
 138
 139         for (fdl = fdhead; fdl; fdl = fdl->next)
 140                 if (strcmp(fdl->nconf->nc_netid, netid) == 0)
 141                         break;
 142         if (fdl == NULL)
 143                 return (TRUE);
 144         return (check_bound(fdl, uaddr));
 145 }
 146
 147 /*
 148  * Returns NULL if there was some system error.
 149  * Returns "" if the address was not bound, i.e the server crashed.
 150  * Returns the merged address otherwise.
 151  */
 152 char *
 153 mergeaddr(SVCXPRT *xprt, char *netid, char *uaddr, char *saddr)
 154 {
 155         struct fdlist *fdl;
 156         char *c_uaddr, *s_uaddr, *m_uaddr, *allocated_uaddr = NULL;
 157
 158         for (fdl = fdhead; fdl; fdl = fdl->next)
 159                 if (strcmp(fdl->nconf->nc_netid, netid) == 0)
 160                         break;
 161         if (fdl == NULL)
 162                 return (NULL);
 163         if (check_bound(fdl, uaddr) == FALSE)
 164                 /* that server died */
 165                 return (nullstring);
 166         /*
 167          * If saddr is not NULL, the remote client may have included the
 168          * address by which it contacted us.  Use that for the "client" uaddr,
 169          * otherwise use the info from the SVCXPRT.
 170          */
 171         if (saddr != NULL) {
 172                 c_uaddr = saddr;
 173         } else {
 174                 c_uaddr = taddr2uaddr(fdl->nconf, svc_getrpccaller(xprt));
 175                 if (c_uaddr == NULL) {
 176                         syslog(LOG_ERR, "taddr2uaddr failed for %s",
 177                                 fdl->nconf->nc_netid);
 178                         return (NULL);
 179                 }
 180                 allocated_uaddr = c_uaddr;
 181         }
 182
 183 #ifdef ND_DEBUG
 184         if (debugging) {
 185                 if (saddr == NULL) {
 186                         fprintf(stderr, "mergeaddr: client uaddr = %s\n",
 187                             c_uaddr);
 188                 } else {
 189                         fprintf(stderr, "mergeaddr: contact uaddr = %s\n",
 190                             c_uaddr);
 191                 }
 192         }
 193 #endif
 194         s_uaddr = uaddr;
 195         /*
 196          * This is all we should need for IP 4 and 6
 197          */
 198         m_uaddr = addrmerge(svc_getrpccaller(xprt), s_uaddr, c_uaddr, netid);
 199 #ifdef ND_DEBUG
 200         if (debugging)
 201                 fprintf(stderr, "mergeaddr: uaddr = %s, merged uaddr = %s\n",
 202                                 uaddr, m_uaddr);
 203 #endif
 204         if (allocated_uaddr != NULL)
 205                 free(allocated_uaddr);
 206         return (m_uaddr);
 207 }
 208
 209 /*
 210  * Returns a netconf structure from its internal list.  This
 211  * structure should not be freed.
 212  */
 213 struct netconfig *
 214 rpcbind_get_conf(char *netid)
 215 {
 216         struct fdlist *fdl;
 217
 218         for (fdl = fdhead; fdl; fdl = fdl->next)
 219                 if (strcmp(fdl->nconf->nc_netid, netid) == 0)
 220                         break;
 221         if (fdl == NULL)
 222                 return (NULL);
 223         return (fdl->nconf);
 224 }