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  * $DragonFly$
  33  */
  34 /*
  35  * Copyright (c) 1986 - 1991 by Sun Microsystems, Inc.
  36  */
  37
  38 /*
  39  * check_bound.c
  40  * Checks to see whether the program is still bound to the
  41  * claimed address and returns the univeral merged address
  42  *
  43  */
  44
  45 #include <sys/types.h>
  46 #include <sys/socket.h>
  47 #include <rpc/rpc.h>
  48 #include <stdio.h>
  49 #include <netconfig.h>
  50 #include <syslog.h>
  51 #include <string.h>
  52 #include <unistd.h>
  53 #include <stdlib.h>
  54
  55 #include "rpcbind.h"
  56
  57 struct fdlist {
  58         int fd;
  59         struct netconfig *nconf;
  60         struct fdlist *next;
  61         int check_binding;
  62 };
  63
  64 static struct fdlist *fdhead;   /* Link list of the check fd's */
  65 static struct fdlist *fdtail;
  66 static char *nullstring = "";
  67
  68 static bool_t   check_bound(struct fdlist *, char *uaddr);
  69
  70 /*
  71  * Returns 1 if the given address is bound for the given addr & transport
  72  * For all error cases, we assume that the address is bound
  73  * Returns 0 for success.
  74  */
  75 static bool_t
  76 check_bound(struct fdlist *fdl, char *uaddr)
  77 {
  78         int fd;
  79         struct netbuf *na;
  80         int ans;
  81
  82         if (fdl->check_binding == FALSE)
  83                 return (TRUE);
  84
  85         na = uaddr2taddr(fdl->nconf, uaddr);
  86         if (!na)
  87                 return (TRUE); /* punt, should never happen */
  88
  89         fd = __rpc_nconf2fd(fdl->nconf);
  90         if (fd < 0) {
  91                 free(na->buf);
  92                 free(na);
  93                 return (TRUE);
  94         }
  95
  96         ans = bind(fd, (struct sockaddr *)na->buf, na->len);
  97
  98         close(fd);
  99         free(na->buf);
 100         free(na);
 101
 102         return (ans == 0 ? FALSE : TRUE);
 103 }
 104
 105 int
 106 add_bndlist(struct netconfig *nconf, struct netbuf *baddr __unused)
 107 {
 108         struct fdlist *fdl;
 109         struct netconfig *newnconf;
 110
 111         newnconf = getnetconfigent(nconf->nc_netid);
 112         if (newnconf == NULL)
 113                 return (-1);
 114         fdl = malloc(sizeof (struct fdlist));
 115         if (fdl == NULL) {
 116                 freenetconfigent(newnconf);
 117                 syslog(LOG_ERR, "no memory!");
 118                 return (-1);
 119         }
 120         fdl->nconf = newnconf;
 121         fdl->next = NULL;
 122         if (fdhead == NULL) {
 123                 fdhead = fdl;
 124                 fdtail = fdl;
 125         } else {
 126                 fdtail->next = fdl;
 127                 fdtail = fdl;
 128         }
 129         /* XXX no bound checking for now */
 130         fdl->check_binding = FALSE;
 131
 132         return 0;
 133 }
 134
 135 bool_t
 136 is_bound(char *netid, char *uaddr)
 137 {
 138         struct fdlist *fdl;
 139
 140         for (fdl = fdhead; fdl; fdl = fdl->next)
 141                 if (strcmp(fdl->nconf->nc_netid, netid) == 0)
 142                         break;
 143         if (fdl == NULL)
 144                 return (TRUE);
 145         return (check_bound(fdl, uaddr));
 146 }
 147
 148 /*
 149  * Returns NULL if there was some system error.
 150  * Returns "" if the address was not bound, i.e the server crashed.
 151  * Returns the merged address otherwise.
 152  */
 153 char *
 154 mergeaddr(SVCXPRT *xprt, char *netid, char *uaddr, char *saddr)
 155 {
 156         struct fdlist *fdl;
 157         char *c_uaddr, *s_uaddr, *m_uaddr, *allocated_uaddr = NULL;
 158
 159         for (fdl = fdhead; fdl; fdl = fdl->next)
 160                 if (strcmp(fdl->nconf->nc_netid, netid) == 0)
 161                         break;
 162         if (fdl == NULL)
 163                 return (NULL);
 164         if (check_bound(fdl, uaddr) == FALSE)
 165                 /* that server died */
 166                 return (nullstring);
 167         /*
 168          * If saddr is not NULL, the remote client may have included the
 169          * address by which it contacted us.  Use that for the "client" uaddr,
 170          * otherwise use the info from the SVCXPRT.
 171          */
 172         if (saddr != NULL) {
 173                 c_uaddr = saddr;
 174         } else {
 175                 c_uaddr = taddr2uaddr(fdl->nconf, svc_getrpccaller(xprt));
 176                 if (c_uaddr == NULL) {
 177                         syslog(LOG_ERR, "taddr2uaddr failed for %s",
 178                                 fdl->nconf->nc_netid);
 179                         return (NULL);
 180                 }
 181                 allocated_uaddr = c_uaddr;
 182         }
 183
 184 #ifdef ND_DEBUG
 185         if (debugging) {
 186                 if (saddr == NULL) {
 187                         fprintf(stderr, "mergeaddr: client uaddr = %s\n",
 188                             c_uaddr);
 189                 } else {
 190                         fprintf(stderr, "mergeaddr: contact uaddr = %s\n",
 191                             c_uaddr);
 192                 }
 193         }
 194 #endif
 195         s_uaddr = uaddr;
 196         /*
 197          * This is all we should need for IP 4 and 6
 198          */
 199         m_uaddr = addrmerge(svc_getrpccaller(xprt), s_uaddr, c_uaddr, netid);
 200 #ifdef ND_DEBUG
 201         if (debugging)
 202                 fprintf(stderr, "mergeaddr: uaddr = %s, merged uaddr = %s\n",
 203                                 uaddr, m_uaddr);
 204 #endif
 205         if (allocated_uaddr != NULL)
 206                 free(allocated_uaddr);
 207         return (m_uaddr);
 208 }
 209
 210 /*
 211  * Returns a netconf structure from its internal list.  This
 212  * structure should not be freed.
 213  */
 214 struct netconfig *
 215 rpcbind_get_conf(char *netid)
 216 {
 217         struct fdlist *fdl;
 218
 219         for (fdl = fdhead; fdl; fdl = fdl->next)
 220                 if (strcmp(fdl->nconf->nc_netid, netid) == 0)
 221                         break;
 222         if (fdl == NULL)
 223                 return (NULL);
 224         return (fdl->nconf);
 225 }