routed.tproj/inet.c

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
   7  *
   8  * This file contains Original Code and/or Modifications of Original Code
   9  * as defined in and that are subject to the Apple Public Source License
  10  * Version 2.0 (the 'License'). You may not use this file except in
  11  * compliance with the License. Please obtain a copy of the License at
  12  * http://www.opensource.apple.com/apsl/ and read it before using this
  13  * file.
  14  *
  15  * The Original Code and all software distributed under the License are
  16  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  17  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  18  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  20  * Please see the License for the specific language governing rights and
  21  * limitations under the License.
  22  *
  23  * @APPLE_LICENSE_HEADER_END@
  24  */
  25 /*
  26  * Copyright (c) 1983, 1993
  27  *      The Regents of the University of California.  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 acknowledgment:
  39  *      This product includes software developed by the University of
  40  *      California, Berkeley and its contributors.
  41  * 4. Neither the name of the University nor the names of its contributors
  42  *    may be used to endorse or promote products derived from this software
  43  *    without specific prior written permission.
  44  *
  45  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  46  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  47  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  48  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  49  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  50  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  51  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  52  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  53  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  54  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  55  * SUCH DAMAGE.
  56  *
  57  *      @(#)defs.h      8.1 (Berkeley) 6/5/93
  58  */
  59
  60
  61 /*
  62  * Temporarily, copy these routines from the kernel,
  63  * as we need to know about subnets.
  64  */
  65 #include "defs.h"
  66
  67 extern struct interface *ifnet;
  68
  69 /*
  70  * Formulate an Internet address from network + host.
  71  */
  72 __private_extern__
  73 struct in_addr
  74 inet_makeaddr(net, host)
  75         u_long net, host;
  76 {
  77         register struct interface *ifp;
  78         register u_long mask;
  79         u_long addr;
  80
  81         if (IN_CLASSA(net))
  82                 mask = IN_CLASSA_HOST;
  83         else if (IN_CLASSB(net))
  84                 mask = IN_CLASSB_HOST;
  85         else
  86                 mask = IN_CLASSC_HOST;
  87         for (ifp = ifnet; ifp; ifp = ifp->int_next)
  88                 if ((ifp->int_netmask & net) == ifp->int_net) {
  89                         mask = ~ifp->int_subnetmask;
  90                         break;
  91                 }
  92         addr = net | (host & mask);
  93         addr = htonl(addr);
  94         return (*(struct in_addr *)&addr);
  95 }
  96
  97 /*
  98  * Return the network number from an internet address.
  99  */
 100 __private_extern__
 101 inet_netof(in)
 102         struct in_addr in;
 103 {
 104         register u_long i = ntohl(in.s_addr);
 105         register u_long net;
 106         register struct interface *ifp;
 107
 108         if (IN_CLASSA(i))
 109                 net = i & IN_CLASSA_NET;
 110         else if (IN_CLASSB(i))
 111                 net = i & IN_CLASSB_NET;
 112         else
 113                 net = i & IN_CLASSC_NET;
 114
 115         /*
 116          * Check whether network is a subnet;
 117          * if so, return subnet number.
 118          */
 119         for (ifp = ifnet; ifp; ifp = ifp->int_next)
 120                 if ((ifp->int_netmask & net) == ifp->int_net)
 121                         return (i & ifp->int_subnetmask);
 122         return (net);
 123 }
 124
 125 /*
 126  * Return the host portion of an internet address.
 127  */
 128 inet_lnaof(in)
 129         struct in_addr in;
 130 {
 131         register u_long i = ntohl(in.s_addr);
 132         register u_long net, host;
 133         register struct interface *ifp;
 134
 135         if (IN_CLASSA(i)) {
 136                 net = i & IN_CLASSA_NET;
 137                 host = i & IN_CLASSA_HOST;
 138         } else if (IN_CLASSB(i)) {
 139                 net = i & IN_CLASSB_NET;
 140                 host = i & IN_CLASSB_HOST;
 141         } else {
 142                 net = i & IN_CLASSC_NET;
 143                 host = i & IN_CLASSC_HOST;
 144         }
 145
 146         /*
 147          * Check whether network is a subnet;
 148          * if so, use the modified interpretation of `host'.
 149          */
 150         for (ifp = ifnet; ifp; ifp = ifp->int_next)
 151                 if ((ifp->int_netmask & net) == ifp->int_net)
 152                         return (host &~ ifp->int_subnetmask);
 153         return (host);
 154 }
 155
 156 /*
 157  * Return the netmask pertaining to an internet address.
 158  */
 159 inet_maskof(inaddr)
 160         u_long inaddr;
 161 {
 162         register u_long i = ntohl(inaddr);
 163         register u_long mask;
 164         register struct interface *ifp;
 165
 166         if (i == 0) {
 167                 mask = 0;
 168         } else if (IN_CLASSA(i)) {
 169                 mask = IN_CLASSA_NET;
 170         } else if (IN_CLASSB(i)) {
 171                 mask = IN_CLASSB_NET;
 172         } else
 173                 mask = IN_CLASSC_NET;
 174
 175         /*
 176          * Check whether network is a subnet;
 177          * if so, use the modified interpretation of `host'.
 178          */
 179         for (ifp = ifnet; ifp; ifp = ifp->int_next)
 180                 if ((ifp->int_netmask & i) == ifp->int_net)
 181                         mask = ifp->int_subnetmask;
 182         return (htonl(mask));
 183 }
 184
 185 /*
 186  * Return RTF_HOST if the address is
 187  * for an Internet host, RTF_SUBNET for a subnet,
 188  * 0 for a network.
 189  */
 190 inet_rtflags(sin)
 191         struct sockaddr_in *sin;
 192 {
 193         register u_long i = ntohl(sin->sin_addr.s_addr);
 194         register u_long net, host;
 195         register struct interface *ifp;
 196
 197         if (IN_CLASSA(i)) {
 198                 net = i & IN_CLASSA_NET;
 199                 host = i & IN_CLASSA_HOST;
 200         } else if (IN_CLASSB(i)) {
 201                 net = i & IN_CLASSB_NET;
 202                 host = i & IN_CLASSB_HOST;
 203         } else {
 204                 net = i & IN_CLASSC_NET;
 205                 host = i & IN_CLASSC_HOST;
 206         }
 207
 208         /*
 209          * Check whether this network is subnetted;
 210          * if so, check whether this is a subnet or a host.
 211          */
 212         for (ifp = ifnet; ifp; ifp = ifp->int_next)
 213                 if (net == ifp->int_net) {
 214                         if (host &~ ifp->int_subnetmask)
 215                                 return (RTF_HOST);
 216                         else if (ifp->int_subnetmask != ifp->int_netmask)
 217                                 return (RTF_SUBNET);
 218                         else
 219                                 return (0);             /* network */
 220                 }
 221         if (host == 0)
 222                 return (0);     /* network */
 223         else
 224                 return (RTF_HOST);
 225 }
 226
 227 /*
 228  * Return true if a route to subnet/host of route rt should be sent to dst.
 229  * Send it only if dst is on the same logical network if not "internal",
 230  * otherwise only if the route is the "internal" route for the logical net.
 231  */
 232 inet_sendroute(rt, dst)
 233         struct rt_entry *rt;
 234         struct sockaddr_in *dst;
 235 {
 236         register u_long r =
 237             ntohl(((struct sockaddr_in *)&rt->rt_dst)->sin_addr.s_addr);
 238         register u_long d = ntohl(dst->sin_addr.s_addr);
 239
 240         if (IN_CLASSA(r)) {
 241                 if ((r & IN_CLASSA_NET) == (d & IN_CLASSA_NET)) {
 242                         if ((r & IN_CLASSA_HOST) == 0)
 243                                 return ((rt->rt_state & RTS_INTERNAL) == 0);
 244                         return (1);
 245                 }
 246                 if (r & IN_CLASSA_HOST)
 247                         return (0);
 248                 return ((rt->rt_state & RTS_INTERNAL) != 0);
 249         } else if (IN_CLASSB(r)) {
 250                 if ((r & IN_CLASSB_NET) == (d & IN_CLASSB_NET)) {
 251                         if ((r & IN_CLASSB_HOST) == 0)
 252                                 return ((rt->rt_state & RTS_INTERNAL) == 0);
 253                         return (1);
 254                 }
 255                 if (r & IN_CLASSB_HOST)
 256                         return (0);
 257                 return ((rt->rt_state & RTS_INTERNAL) != 0);
 258         } else {
 259                 if ((r & IN_CLASSC_NET) == (d & IN_CLASSC_NET)) {
 260                         if ((r & IN_CLASSC_HOST) == 0)
 261                                 return ((rt->rt_state & RTS_INTERNAL) == 0);
 262                         return (1);
 263                 }
 264                 if (r & IN_CLASSC_HOST)
 265                         return (0);
 266                 return ((rt->rt_state & RTS_INTERNAL) != 0);
 267         }
 268 }