1 /** 2 * @file 3 * 4 * AutoIP Automatic LinkLocal IP Configuration 5 */ 6 7 /* 8 * 9 * Copyright (c) 2007 Dominik Spies <kontakt (at) dspies.de> 10 * All rights reserved. 11 * 12 * Redistribution and use in source and binary forms, with or without modification, 13 * are permitted provided that the following conditions are met: 14 * 15 * 1. Redistributions of source code must retain the above copyright notice, 16 * this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright notice, 18 * this list of conditions and the following disclaimer in the documentation 19 * and/or other materials provided with the distribution. 20 * 3. The name of the author may not be used to endorse or promote products 21 * derived from this software without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 24 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 25 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 26 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 27 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 28 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 29 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 30 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 31 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 32 * OF SUCH DAMAGE. 33 * 34 * Author: Dominik Spies <kontakt (at) dspies.de> 35 * 36 * This is a AutoIP implementation for the lwIP TCP/IP stack. It aims to conform 37 * with RFC 3927. 38 * 39 * 40 * Please coordinate changes and requests with Dominik Spies 41 * <kontakt (at) dspies.de> 42 */ 43 44 #ifndef __LWIP_AUTOIP_H__ 45 #define __LWIP_AUTOIP_H__ 46 47 #include "lwip/opt.h" 48 49 #if LWIP_AUTOIP /* don't build if not configured for use in lwipopts.h */ 50 51 #include "lwip/netif.h" 52 #include "lwip/udp.h" 53 #include "netif/etharp.h" 54 55 #ifdef __cplusplus 56 extern "C" { 57 #endif 58 59 /* AutoIP Timing */ 60 #define AUTOIP_TMR_INTERVAL 100 61 #define AUTOIP_TICKS_PER_SECOND (1000 / AUTOIP_TMR_INTERVAL) 62 63 /* RFC 3927 Constants */ 64 #define PROBE_WAIT 1 /* second (initial random delay) */ 65 #define PROBE_MIN 1 /* second (minimum delay till repeated probe) */ 66 #define PROBE_MAX 2 /* seconds (maximum delay till repeated probe) */ 67 #define PROBE_NUM 3 /* (number of probe packets) */ 68 #define ANNOUNCE_NUM 2 /* (number of announcement packets) */ 69 #define ANNOUNCE_INTERVAL 2 /* seconds (time between announcement packets) */ 70 #define ANNOUNCE_WAIT 2 /* seconds (delay before announcing) */ 71 #define MAX_CONFLICTS 10 /* (max conflicts before rate limiting) */ 72 #define RATE_LIMIT_INTERVAL 60 /* seconds (delay between successive attempts) */ 73 #define DEFEND_INTERVAL 10 /* seconds (min. wait between defensive ARPs) */ 74 75 /* AutoIP client states */ 76 #define AUTOIP_STATE_OFF 0 77 #define AUTOIP_STATE_PROBING 1 78 #define AUTOIP_STATE_ANNOUNCING 2 79 #define AUTOIP_STATE_BOUND 3 80 81 struct autoip 82 { 83 ip_addr_t llipaddr; /* the currently selected, probed, announced or used LL IP-Address */ 84 u8_t state; /* current AutoIP state machine state */ 85 u8_t sent_num; /* sent number of probes or announces, dependent on state */ 86 u16_t ttw; /* ticks to wait, tick is AUTOIP_TMR_INTERVAL long */ 87 u8_t lastconflict; /* ticks until a conflict can be solved by defending */ 88 u8_t tried_llipaddr; /* total number of probed/used Link Local IP-Addresses */ 89 }; 90 91 92 /** Init srand, has to be called before entering mainloop */ 93 void autoip_init(void); 94 95 /** Set a struct autoip allocated by the application to work with */ 96 void autoip_set_struct(struct netif *netif, struct autoip *autoip); 97 98 /** Start AutoIP client */ 99 err_t autoip_start(struct netif *netif); 100 101 /** Stop AutoIP client */ 102 err_t autoip_stop(struct netif *netif); 103 104 /** Handles every incoming ARP Packet, called by etharp_arp_input */ 105 void autoip_arp_reply(struct netif *netif, struct etharp_hdr *hdr); 106 107 /** Has to be called in loop every AUTOIP_TMR_INTERVAL milliseconds */ 108 void autoip_tmr(void); 109 110 /** Handle a possible change in the network configuration */ 111 void autoip_network_changed(struct netif *netif); 112 113 #ifdef __cplusplus 114 } 115 #endif 116 117 #endif /* LWIP_AUTOIP */ 118 119 #endif /* __LWIP_AUTOIP_H__ */ 120
