lib/drivers/lwip/src/include/ipv4/lwip/autoip.h

   1 /**
   2  * @file
   3  *
   4  * AutoIP Automatic LinkLocal IP Configuration
   5  */
   6
   7 /*
   8  *
   9  * Copyright (c) 2007 Dominik Spies <kontakt@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@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@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   struct ip_addr 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 /** Start AutoIP client */
  96 err_t autoip_start(struct netif *netif);
  97
  98 /** Stop AutoIP client */
  99 err_t autoip_stop(struct netif *netif);
 100
 101 /** Handles every incoming ARP Packet, called by etharp_arp_input */
 102 void autoip_arp_reply(struct netif *netif, struct etharp_hdr *hdr);
 103
 104 /** Has to be called in loop every AUTOIP_TMR_INTERVAL milliseconds */
 105 void autoip_tmr(void);
 106
 107 /** Handle a possible change in the network configuration */
 108 void autoip_network_changed(struct netif *netif);
 109
 110 #ifdef __cplusplus
 111 }
 112 #endif
 113
 114 #endif /* LWIP_AUTOIP */
 115
 116 #endif /* __LWIP_AUTOIP_H__ */