| 1 | /* |
| 2 | * Copyright (c) 1983 Regents of the University of California. |
| 3 | * All rights reserved. |
| 4 | * |
| 5 | * Redistribution and use in source and binary forms, with or without |
| 6 | * modification, are permitted provided that the following conditions |
| 7 | * are met: |
| 8 | * 1. Redistributions of source code must retain the above copyright |
| 9 | * notice, this list of conditions and the following disclaimer. |
| 10 | * 2. Redistributions in binary form must reproduce the above copyright |
| 11 | * notice, this list of conditions and the following disclaimer in the |
| 12 | * documentation and/or other materials provided with the distribution. |
| 13 | * 3. All advertising materials mentioning features or use of this software |
| 14 | * must display the following acknowledgement: |
| 15 | * This product includes software developed by the University of |
| 16 | * California, Berkeley and its contributors. |
| 17 | * 4. Neither the name of the University nor the names of its contributors |
| 18 | * may be used to endorse or promote products derived from this software |
| 19 | * without specific prior written permission. |
| 20 | * |
| 21 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| 22 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 23 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 24 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| 25 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 26 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 27 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 28 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 29 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 30 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 31 | * SUCH DAMAGE. |
| 32 | */ |
| 33 | |
| 34 | #ifndef lint |
| 35 | static char sccsid[] = "@(#)inet.c 5.8 (Berkeley) 6/1/90"; |
| 36 | #endif /* not lint */ |
| 37 | |
| 38 | /* |
| 39 | * Temporarily, copy these routines from the kernel, |
| 40 | * as we need to know about subnets. |
| 41 | */ |
| 42 | #include "defs.h" |
| 43 | |
| 44 | extern struct interface *ifnet; |
| 45 | |
| 46 | /* |
| 47 | * Formulate an Internet address from network + host. |
| 48 | */ |
| 49 | struct in_addr |
| 50 | inet_makeaddr(net, host) |
| 51 | u_long net, host; |
| 52 | { |
| 53 | register struct interface *ifp; |
| 54 | register u_long mask; |
| 55 | u_long addr; |
| 56 | |
| 57 | if (IN_CLASSA(net)) |
| 58 | mask = IN_CLASSA_HOST; |
| 59 | else if (IN_CLASSB(net)) |
| 60 | mask = IN_CLASSB_HOST; |
| 61 | else |
| 62 | mask = IN_CLASSC_HOST; |
| 63 | for (ifp = ifnet; ifp; ifp = ifp->int_next) |
| 64 | if ((ifp->int_netmask & net) == ifp->int_net) { |
| 65 | mask = ~ifp->int_subnetmask; |
| 66 | break; |
| 67 | } |
| 68 | addr = net | (host & mask); |
| 69 | addr = htonl(addr); |
| 70 | return (*(struct in_addr *)&addr); |
| 71 | } |
| 72 | |
| 73 | /* |
| 74 | * Return the network number from an internet address. |
| 75 | */ |
| 76 | inet_netof(in) |
| 77 | struct in_addr in; |
| 78 | { |
| 79 | register u_long i = ntohl(in.s_addr); |
| 80 | register u_long net; |
| 81 | register struct interface *ifp; |
| 82 | |
| 83 | if (IN_CLASSA(i)) |
| 84 | net = i & IN_CLASSA_NET; |
| 85 | else if (IN_CLASSB(i)) |
| 86 | net = i & IN_CLASSB_NET; |
| 87 | else |
| 88 | net = i & IN_CLASSC_NET; |
| 89 | |
| 90 | /* |
| 91 | * Check whether network is a subnet; |
| 92 | * if so, return subnet number. |
| 93 | */ |
| 94 | for (ifp = ifnet; ifp; ifp = ifp->int_next) |
| 95 | if ((ifp->int_netmask & net) == ifp->int_net) |
| 96 | return (i & ifp->int_subnetmask); |
| 97 | return (net); |
| 98 | } |
| 99 | |
| 100 | /* |
| 101 | * Return the host portion of an internet address. |
| 102 | */ |
| 103 | inet_lnaof(in) |
| 104 | struct in_addr in; |
| 105 | { |
| 106 | register u_long i = ntohl(in.s_addr); |
| 107 | register u_long net, host; |
| 108 | register struct interface *ifp; |
| 109 | |
| 110 | if (IN_CLASSA(i)) { |
| 111 | net = i & IN_CLASSA_NET; |
| 112 | host = i & IN_CLASSA_HOST; |
| 113 | } else if (IN_CLASSB(i)) { |
| 114 | net = i & IN_CLASSB_NET; |
| 115 | host = i & IN_CLASSB_HOST; |
| 116 | } else { |
| 117 | net = i & IN_CLASSC_NET; |
| 118 | host = i & IN_CLASSC_HOST; |
| 119 | } |
| 120 | |
| 121 | /* |
| 122 | * Check whether network is a subnet; |
| 123 | * if so, use the modified interpretation of `host'. |
| 124 | */ |
| 125 | for (ifp = ifnet; ifp; ifp = ifp->int_next) |
| 126 | if ((ifp->int_netmask & net) == ifp->int_net) |
| 127 | return (host &~ ifp->int_subnetmask); |
| 128 | return (host); |
| 129 | } |
| 130 | |
| 131 | /* |
| 132 | * Return RTF_HOST if the address is |
| 133 | * for an Internet host, RTF_SUBNET for a subnet, |
| 134 | * 0 for a network. |
| 135 | */ |
| 136 | inet_rtflags(sin) |
| 137 | struct sockaddr_in *sin; |
| 138 | { |
| 139 | register u_long i = ntohl(sin->sin_addr.s_addr); |
| 140 | register u_long net, host; |
| 141 | register struct interface *ifp; |
| 142 | |
| 143 | if (IN_CLASSA(i)) { |
| 144 | net = i & IN_CLASSA_NET; |
| 145 | host = i & IN_CLASSA_HOST; |
| 146 | } else if (IN_CLASSB(i)) { |
| 147 | net = i & IN_CLASSB_NET; |
| 148 | host = i & IN_CLASSB_HOST; |
| 149 | } else { |
| 150 | net = i & IN_CLASSC_NET; |
| 151 | host = i & IN_CLASSC_HOST; |
| 152 | } |
| 153 | |
| 154 | /* |
| 155 | * Check whether this network is subnetted; |
| 156 | * if so, check whether this is a subnet or a host. |
| 157 | */ |
| 158 | for (ifp = ifnet; ifp; ifp = ifp->int_next) |
| 159 | if (net == ifp->int_net) { |
| 160 | if (host &~ ifp->int_subnetmask) |
| 161 | return (RTF_HOST); |
| 162 | else if (ifp->int_subnetmask != ifp->int_netmask) |
| 163 | return (RTF_SUBNET); |
| 164 | else |
| 165 | return (0); /* network */ |
| 166 | } |
| 167 | if (host == 0) |
| 168 | return (0); /* network */ |
| 169 | else |
| 170 | return (RTF_HOST); |
| 171 | } |
| 172 | |
| 173 | /* |
| 174 | * Return true if a route to subnet/host of route rt should be sent to dst. |
| 175 | * Send it only if dst is on the same logical network if not "internal", |
| 176 | * otherwise only if the route is the "internal" route for the logical net. |
| 177 | */ |
| 178 | inet_sendroute(rt, dst) |
| 179 | struct rt_entry *rt; |
| 180 | struct sockaddr_in *dst; |
| 181 | { |
| 182 | register u_long r = |
| 183 | ntohl(((struct sockaddr_in *)&rt->rt_dst)->sin_addr.s_addr); |
| 184 | register u_long d = ntohl(dst->sin_addr.s_addr); |
| 185 | |
| 186 | if (IN_CLASSA(r)) { |
| 187 | if ((r & IN_CLASSA_NET) == (d & IN_CLASSA_NET)) { |
| 188 | if ((r & IN_CLASSA_HOST) == 0) |
| 189 | return ((rt->rt_state & RTS_INTERNAL) == 0); |
| 190 | return (1); |
| 191 | } |
| 192 | if (r & IN_CLASSA_HOST) |
| 193 | return (0); |
| 194 | return ((rt->rt_state & RTS_INTERNAL) != 0); |
| 195 | } else if (IN_CLASSB(r)) { |
| 196 | if ((r & IN_CLASSB_NET) == (d & IN_CLASSB_NET)) { |
| 197 | if ((r & IN_CLASSB_HOST) == 0) |
| 198 | return ((rt->rt_state & RTS_INTERNAL) == 0); |
| 199 | return (1); |
| 200 | } |
| 201 | if (r & IN_CLASSB_HOST) |
| 202 | return (0); |
| 203 | return ((rt->rt_state & RTS_INTERNAL) != 0); |
| 204 | } else { |
| 205 | if ((r & IN_CLASSC_NET) == (d & IN_CLASSC_NET)) { |
| 206 | if ((r & IN_CLASSC_HOST) == 0) |
| 207 | return ((rt->rt_state & RTS_INTERNAL) == 0); |
| 208 | return (1); |
| 209 | } |
| 210 | if (r & IN_CLASSC_HOST) |
| 211 | return (0); |
| 212 | return ((rt->rt_state & RTS_INTERNAL) != 0); |
| 213 | } |
| 214 | } |