1/** 2 * @file 3 * This is the IPv4 address tools implementation. 4 * 5 */ 6 7/* 8 * Copyright (c) 2001-2004 Swedish Institute of Computer Science. 9 * All rights reserved. 10 * 11 * Redistribution and use in source and binary forms, with or without modification, 12 * are permitted provided that the following conditions are met: 13 * 14 * 1. Redistributions of source code must retain the above copyright notice, 15 * this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright notice, 17 * this list of conditions and the following disclaimer in the documentation 18 * and/or other materials provided with the distribution. 19 * 3. The name of the author may not be used to endorse or promote products 20 * derived from this software without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 23 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 24 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 25 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 26 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 27 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 29 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 30 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 31 * OF SUCH DAMAGE. 32 * 33 * This file is part of the lwIP TCP/IP stack. 34 * 35 * Author: Adam Dunkels <adam@sics.se> 36 * 37 */ 38 39#include "lwip/opt.h" 40#include "lwip/ip_addr.h" 41#include "lwip/inet.h" 42#include "lwip/netif.h" 43 44#define IP_ADDR_ANY_VALUE 0x00000000UL 45#define IP_ADDR_BROADCAST_VALUE 0xffffffffUL 46 47/* used by IP_ADDR_ANY and IP_ADDR_BROADCAST in ip_addr.h */ 48const struct ip_addr ip_addr_any = { IP_ADDR_ANY_VALUE }; 49const struct ip_addr ip_addr_broadcast = { IP_ADDR_BROADCAST_VALUE }; 50 51/** 52 * Determine if an address is a broadcast address on a network interface 53 * 54 * @param addr address to be checked 55 * @param netif the network interface against which the address is checked 56 * @return returns non-zero if the address is a broadcast address 57 */ 58u8_t ip_addr_isbroadcast(struct ip_addr *addr, struct netif *netif) 59{ 60 u32_t addr2test; 61 62 addr2test = addr->addr; 63 /* all ones (broadcast) or all zeroes (old skool broadcast) */ 64 if ((~addr2test == IP_ADDR_ANY_VALUE) || (addr2test == IP_ADDR_ANY_VALUE)) 65 return 1; 66 /* no broadcast support on this network interface? */ 67 else if ((netif->flags & NETIF_FLAG_BROADCAST) == 0) 68 /* the given address cannot be a broadcast address 69 * nor can we check against any broadcast addresses */ 70 return 0; 71 /* address matches network interface address exactly? => no broadcast */ 72 else if (addr2test == netif->ip_addr.addr) 73 return 0; 74 /* on the same (sub) network... */ 75 else if (ip_addr_netcmp(addr, &(netif->ip_addr), &(netif->netmask)) 76 /* ...and host identifier bits are all ones? =>... */ 77 && ((addr2test & ~netif->netmask.addr) == 78 (IP_ADDR_BROADCAST_VALUE & ~netif->netmask.addr))) 79 /* => network broadcast address */ 80 return 1; 81 else 82 return 0; 83} 84