routed.tproj/inet.c

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