routed.tproj/inet.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 1.0 (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) 1983, 1993
  26  *      The Regents of the University of California.  All rights reserved.
  27  *
  28  * Redistribution and use in source and binary forms, with or without
  29  * modification, are permitted provided that the following conditions
  30  * are met:
  31  * 1. Redistributions of source code must retain the above copyright
  32  *    notice, this list of conditions and the following disclaimer.
  33  * 2. Redistributions in binary form must reproduce the above copyright
  34  *    notice, this list of conditions and the following disclaimer in the
  35  *    documentation and/or other materials provided with the distribution.
  36  * 3. All advertising materials mentioning features or use of this software
  37  *    must display the following acknowledgment:
  38  *      This product includes software developed by the University of
  39  *      California, Berkeley and its contributors.
  40  * 4. Neither the name of the University nor the names of its contributors
  41  *    may be used to endorse or promote products derived from this software
  42  *    without specific prior written permission.
  43  *
  44  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  45  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  46  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  47  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  48  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  49  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  50  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  51  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  52  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  53  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  54  * SUCH DAMAGE.
  55  *
  56  *      @(#)defs.h      8.1 (Berkeley) 6/5/93
  57  */
  58
  59
  60 /*
  61  * Temporarily, copy these routines from the kernel,
  62  * as we need to know about subnets.
  63  */
  64 #include "defs.h"
  65
  66 extern struct interface *ifnet;
  67
  68 /*
  69  * Formulate an Internet address from network + host.
  70  */
  71 __private_extern__
  72 struct in_addr
  73 inet_makeaddr(net, host)
  74         u_long net, host;
  75 {
  76         register struct interface *ifp;
  77         register u_long mask;
  78         u_long addr;
  79
  80         if (IN_CLASSA(net))
  81                 mask = IN_CLASSA_HOST;
  82         else if (IN_CLASSB(net))
  83                 mask = IN_CLASSB_HOST;
  84         else
  85                 mask = IN_CLASSC_HOST;
  86         for (ifp = ifnet; ifp; ifp = ifp->int_next)
  87                 if ((ifp->int_netmask & net) == ifp->int_net) {
  88                         mask = ~ifp->int_subnetmask;
  89                         break;
  90                 }
  91         addr = net | (host & mask);
  92         addr = htonl(addr);
  93         return (*(struct in_addr *)&addr);
  94 }
  95
  96 /*
  97  * Return the network number from an internet address.
  98  */
  99 __private_extern__
 100 inet_netof(in)
 101         struct in_addr in;
 102 {
 103         register u_long i = ntohl(in.s_addr);
 104         register u_long net;
 105         register struct interface *ifp;
 106
 107         if (IN_CLASSA(i))
 108                 net = i & IN_CLASSA_NET;
 109         else if (IN_CLASSB(i))
 110                 net = i & IN_CLASSB_NET;
 111         else
 112                 net = i & IN_CLASSC_NET;
 113
 114         /*
 115          * Check whether network is a subnet;
 116          * if so, return subnet number.
 117          */
 118         for (ifp = ifnet; ifp; ifp = ifp->int_next)
 119                 if ((ifp->int_netmask & net) == ifp->int_net)
 120                         return (i & ifp->int_subnetmask);
 121         return (net);
 122 }
 123
 124 /*
 125  * Return the host portion of an internet address.
 126  */
 127 inet_lnaof(in)
 128         struct in_addr in;
 129 {
 130         register u_long i = ntohl(in.s_addr);
 131         register u_long net, host;
 132         register struct interface *ifp;
 133
 134         if (IN_CLASSA(i)) {
 135                 net = i & IN_CLASSA_NET;
 136                 host = i & IN_CLASSA_HOST;
 137         } else if (IN_CLASSB(i)) {
 138                 net = i & IN_CLASSB_NET;
 139                 host = i & IN_CLASSB_HOST;
 140         } else {
 141                 net = i & IN_CLASSC_NET;
 142                 host = i & IN_CLASSC_HOST;
 143         }
 144
 145         /*
 146          * Check whether network is a subnet;
 147          * if so, use the modified interpretation of `host'.
 148          */
 149         for (ifp = ifnet; ifp; ifp = ifp->int_next)
 150                 if ((ifp->int_netmask & net) == ifp->int_net)
 151                         return (host &~ ifp->int_subnetmask);
 152         return (host);
 153 }
 154
 155 /*
 156  * Return the netmask pertaining to an internet address.
 157  */
 158 inet_maskof(inaddr)
 159         u_long inaddr;
 160 {
 161         register u_long i = ntohl(inaddr);
 162         register u_long mask;
 163         register struct interface *ifp;
 164
 165         if (i == 0) {
 166                 mask = 0;
 167         } else if (IN_CLASSA(i)) {
 168                 mask = IN_CLASSA_NET;
 169         } else if (IN_CLASSB(i)) {
 170                 mask = IN_CLASSB_NET;
 171         } else
 172                 mask = IN_CLASSC_NET;
 173
 174         /*
 175          * Check whether network is a subnet;
 176          * if so, use the modified interpretation of `host'.
 177          */
 178         for (ifp = ifnet; ifp; ifp = ifp->int_next)
 179                 if ((ifp->int_netmask & i) == ifp->int_net)
 180                         mask = ifp->int_subnetmask;
 181         return (htonl(mask));
 182 }
 183
 184 /*
 185  * Return RTF_HOST if the address is
 186  * for an Internet host, RTF_SUBNET for a subnet,
 187  * 0 for a network.
 188  */
 189 inet_rtflags(sin)
 190         struct sockaddr_in *sin;
 191 {
 192         register u_long i = ntohl(sin->sin_addr.s_addr);
 193         register u_long net, host;
 194         register struct interface *ifp;
 195
 196         if (IN_CLASSA(i)) {
 197                 net = i & IN_CLASSA_NET;
 198                 host = i & IN_CLASSA_HOST;
 199         } else if (IN_CLASSB(i)) {
 200                 net = i & IN_CLASSB_NET;
 201                 host = i & IN_CLASSB_HOST;
 202         } else {
 203                 net = i & IN_CLASSC_NET;
 204                 host = i & IN_CLASSC_HOST;
 205         }
 206
 207         /*
 208          * Check whether this network is subnetted;
 209          * if so, check whether this is a subnet or a host.
 210          */
 211         for (ifp = ifnet; ifp; ifp = ifp->int_next)
 212                 if (net == ifp->int_net) {
 213                         if (host &~ ifp->int_subnetmask)
 214                                 return (RTF_HOST);
 215                         else if (ifp->int_subnetmask != ifp->int_netmask)
 216                                 return (RTF_SUBNET);
 217                         else
 218                                 return (0);             /* network */
 219                 }
 220         if (host == 0)
 221                 return (0);     /* network */
 222         else
 223                 return (RTF_HOST);
 224 }
 225
 226 /*
 227  * Return true if a route to subnet/host of route rt should be sent to dst.
 228  * Send it only if dst is on the same logical network if not "internal",
 229  * otherwise only if the route is the "internal" route for the logical net.
 230  */
 231 inet_sendroute(rt, dst)
 232         struct rt_entry *rt;
 233         struct sockaddr_in *dst;
 234 {
 235         register u_long r =
 236             ntohl(((struct sockaddr_in *)&rt->rt_dst)->sin_addr.s_addr);
 237         register u_long d = ntohl(dst->sin_addr.s_addr);
 238
 239         if (IN_CLASSA(r)) {
 240                 if ((r & IN_CLASSA_NET) == (d & IN_CLASSA_NET)) {
 241                         if ((r & IN_CLASSA_HOST) == 0)
 242                                 return ((rt->rt_state & RTS_INTERNAL) == 0);
 243                         return (1);
 244                 }
 245                 if (r & IN_CLASSA_HOST)
 246                         return (0);
 247                 return ((rt->rt_state & RTS_INTERNAL) != 0);
 248         } else if (IN_CLASSB(r)) {
 249                 if ((r & IN_CLASSB_NET) == (d & IN_CLASSB_NET)) {
 250                         if ((r & IN_CLASSB_HOST) == 0)
 251                                 return ((rt->rt_state & RTS_INTERNAL) == 0);
 252                         return (1);
 253                 }
 254                 if (r & IN_CLASSB_HOST)
 255                         return (0);
 256                 return ((rt->rt_state & RTS_INTERNAL) != 0);
 257         } else {
 258                 if ((r & IN_CLASSC_NET) == (d & IN_CLASSC_NET)) {
 259                         if ((r & IN_CLASSC_HOST) == 0)
 260                                 return ((rt->rt_state & RTS_INTERNAL) == 0);
 261                         return (1);
 262                 }
 263                 if (r & IN_CLASSC_HOST)
 264                         return (0);
 265                 return ((rt->rt_state & RTS_INTERNAL) != 0);
 266         }
 267 }