| Travis Geiselbrecht | 1d0df69 | 2008-09-01 02:26:09 -0700 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright (c) 2001-2004 Swedish Institute of Computer Science. |
| 3 | * All rights reserved. |
| 4 | * |
| 5 | * Redistribution and use in source and binary forms, with or without modification, |
| 6 | * are permitted provided that the following conditions are met: |
| 7 | * |
| 8 | * 1. Redistributions of source code must retain the above copyright notice, |
| 9 | * this list of conditions and the following disclaimer. |
| 10 | * 2. Redistributions in binary form must reproduce the above copyright notice, |
| 11 | * this list of conditions and the following disclaimer in the documentation |
| 12 | * and/or other materials provided with the distribution. |
| 13 | * 3. The name of the author may not be used to endorse or promote products |
| 14 | * derived from this software without specific prior written permission. |
| 15 | * |
| 16 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED |
| 17 | * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF |
| 18 | * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT |
| 19 | * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
| 20 | * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT |
| 21 | * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| 22 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| 23 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING |
| 24 | * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY |
| 25 | * OF SUCH DAMAGE. |
| 26 | * |
| 27 | * This file is part of the lwIP TCP/IP stack. |
| 28 | * |
| 29 | * Author: Adam Dunkels <adam@sics.se> |
| 30 | * |
| 31 | */ |
| 32 | |
| 33 | #include "lwip/ip_addr.h" |
| 34 | #include "lwip/inet.h" |
| 35 | #include "lwip/netif.h" |
| 36 | |
| 37 | /* used by IP_ADDR_ANY and IP_ADDR_BROADCAST in ip_addr.h */ |
| 38 | const struct ip_addr ip_addr_any = { 0x00000000UL }; |
| 39 | const struct ip_addr ip_addr_broadcast = { 0xffffffffUL }; |
| 40 | |
| 41 | /* Determine if an address is a broadcast address on a network interface |
| 42 | * |
| 43 | * @param addr address to be checked |
| 44 | * @param netif the network interface against which the address is checked |
| 45 | * @return returns non-zero if the address is a broadcast address |
| 46 | * |
| 47 | */ |
| 48 | |
| 49 | u8_t ip_addr_isbroadcast(struct ip_addr *addr, struct netif *netif) |
| 50 | { |
| 51 | /* all ones (broadcast) or all zeroes (old skool broadcast) */ |
| 52 | if ((addr->addr == ip_addr_broadcast.addr) || |
| 53 | (addr->addr == ip_addr_any.addr)) |
| 54 | return 1; |
| 55 | /* no broadcast support on this network interface? */ |
| 56 | else if ((netif->flags & NETIF_FLAG_BROADCAST) == 0) |
| 57 | /* the given address cannot be a broadcast address |
| 58 | * nor can we check against any broadcast addresses */ |
| 59 | return 0; |
| 60 | /* address matches network interface address exactly? => no broadcast */ |
| 61 | else if (addr->addr == netif->ip_addr.addr) |
| 62 | return 0; |
| 63 | /* on the same (sub) network... */ |
| 64 | else if (ip_addr_netcmp(addr, &(netif->ip_addr), &(netif->netmask)) |
| 65 | /* ...and host identifier bits are all ones? =>... */ |
| 66 | && ((addr->addr & ~netif->netmask.addr) == |
| 67 | (ip_addr_broadcast.addr & ~netif->netmask.addr))) |
| 68 | /* => network broadcast address */ |
| 69 | return 1; |
| 70 | else |
| 71 | return 0; |
| 72 | } |