📄 arp_8c-source.html
字号:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html><head><meta http-equiv="Content-Type" content="text/html;charset=iso-8859-1"><title>Procyon AVRlib: net/arp.c Source File</title><link href="dox.css" rel="stylesheet" type="text/css"></head><body><!-- Generated by Doxygen 1.4.2 --><div class="qindex"><a class="qindex" href="main.html">Main Page</a> | <a class="qindex" href="modules.html">Modules</a> | <a class="qindex" href="annotated.html">Data Structures</a> | <a class="qindex" href="dirs.html">Directories</a> | <a class="qindex" href="files.html">File List</a> | <a class="qindex" href="functions.html">Data Fields</a> | <a class="qindex" href="globals.html">Globals</a> | <a class="qindex" href="pages.html">Related Pages</a></div><div class="nav"><a class="el" href="dir_000001.html">net</a></div><h1>arp.c</h1><a href="arp_8c.html">Go to the documentation of this file.</a><div class="fragment"><pre class="fragment">00001 <span class="comment">/*! \file arp.c \brief ARP Protocol Library. */</span>00002 <span class="comment">//*****************************************************************************</span>00003 <span class="comment">//</span>00004 <span class="comment">// File Name : 'arp.c'</span>00005 <span class="comment">// Title : ARP Protocol Library</span>00006 <span class="comment">// Author : Pascal Stang</span>00007 <span class="comment">// Created : 9/7/2004</span>00008 <span class="comment">// Revised : 7/3/2005</span>00009 <span class="comment">// Version : 0.1</span>00010 <span class="comment">// Target MCU : Atmel AVR series</span>00011 <span class="comment">// Editor Tabs : 4</span>00012 <span class="comment">//</span>00013 <span class="comment">//*****************************************************************************</span>00014 00015 <span class="preprocessor">#include "<a class="code" href="global_8h.html">global.h</a>"</span>00016 <span class="preprocessor">#include "<a class="code" href="net_8h.html">net.h</a>"</span>00017 <span class="preprocessor">#include "<a class="code" href="nic_8h.html">nic.h</a>"</span>00018 <span class="preprocessor">#include "<a class="code" href="arp_8h.html">arp.h</a>"</span>00019 00020 <span class="preprocessor">#include "<a class="code" href="rprintf_8h.html">rprintf.h</a>"</span>00021 00022 <span class="comment">// global variables</span>00023 <span class="comment"></span>00024 <span class="comment">/// Single ARP table entry/record</span>00025 <span class="comment"></span><span class="keyword">struct </span>ArpEntry00026 {00027 uint32_t ipaddr; <span class="comment">///< remote-note IP address</span>00028 <span class="comment"></span> <span class="keyword">struct </span>netEthAddr ethaddr; <span class="comment">///< remote-node ethernet (hardware/mac) address</span>00029 <span class="comment"></span> uint8_t time; <span class="comment">///< time to live (in ARP table); this is decremented by arpTimer()</span>00030 <span class="comment"></span>};00031 <a name="l00032"></a><a class="code" href="arp_8c.html#a0">00032</a> <span class="keyword">struct </span>ArpEntry ArpMyAddr; <span class="comment">///< my local interface information (IP and MAC address)</span><a name="l00033"></a><a class="code" href="arp_8c.html#a1">00033</a> <span class="comment"></span><span class="keyword">struct </span>ArpEntry ArpTable[ARP_TABLE_SIZE]; <span class="comment">///< ARP table of matched IP<->MAC associations</span>00034 <span class="comment"></span>00035 <a name="l00036"></a><a class="code" href="group__arp.html#ga0">00036</a> <span class="keywordtype">void</span> <a class="code" href="group__arp.html#ga0">arpInit</a>(<span class="keywordtype">void</span>)00037 {00038 u08 i;00039 <span class="comment">// initialize all ArpTable elements to unused</span>00040 <span class="keywordflow">for</span>(i=0; i<ARP_TABLE_SIZE; i++)00041 {00042 ArpTable[i].ipaddr = 0;00043 ArpTable[i].time = 0;00044 }00045 }00046 <a name="l00047"></a><a class="code" href="group__arp.html#ga1">00047</a> <span class="keywordtype">void</span> <a class="code" href="group__arp.html#ga1">arpSetAddress</a>(<span class="keyword">struct</span> netEthAddr* myeth, uint32_t myip)00048 {00049 <span class="comment">// set local address record</span>00050 ArpMyAddr.ethaddr = *myeth;00051 ArpMyAddr.ipaddr = myip;00052 }00053 <a name="l00054"></a><a class="code" href="group__arp.html#ga2">00054</a> <span class="keywordtype">void</span> <a class="code" href="group__arp.html#ga2">arpArpIn</a>(<span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> len, <span class="keyword">struct</span> netEthArpHeader* packet)00055 {00056 <span class="preprocessor"> #ifdef ARP_DEBUG</span>00057 <span class="preprocessor"></span> <a class="code" href="group__rprintf.html#ga15">rprintfProgStrM</a>(<span class="stringliteral">"Received ARP Request\r\n"</span>);00058 <a class="code" href="group__arp.html#ga7">arpPrintHeader</a>( &packet->arp );00059 <span class="preprocessor"> #endif</span>00060 <span class="preprocessor"></span>00061 <span class="comment">// for now, we just reply to requests</span>00062 <span class="comment">// need to add ARP cache</span>00063 <span class="keywordflow">if</span>( (packet->arp.dipaddr == <a class="code" href="group__net.html#ga34">HTONL</a>(ArpMyAddr.ipaddr)) &&00064 (packet->arp.opcode == <a class="code" href="group__net.html#ga2">htons</a>(ARP_OPCODE_REQUEST)) )00065 {00066 <span class="comment">// in ARP header</span>00067 <span class="comment">// copy sender's address info to dest. fields</span>00068 packet->arp.dhwaddr = packet->arp.shwaddr;00069 packet->arp.dipaddr = packet->arp.sipaddr;00070 <span class="comment">// fill in our information</span>00071 packet->arp.shwaddr = ArpMyAddr.ethaddr;00072 packet->arp.sipaddr = <a class="code" href="group__net.html#ga34">HTONL</a>(ArpMyAddr.ipaddr);00073 <span class="comment">// change op to reply</span>00074 packet->arp.opcode = <a class="code" href="group__net.html#ga2">htons</a>(ARP_OPCODE_REPLY);00075 00076 <span class="comment">// in ethernet header</span>00077 packet->eth.dest = packet->eth.src;00078 packet->eth.src = ArpMyAddr.ethaddr;00079 00080 <span class="preprocessor"> #ifdef ARP_DEBUG</span>00081 <span class="preprocessor"></span> <a class="code" href="group__rprintf.html#ga15">rprintfProgStrM</a>(<span class="stringliteral">"Sending ARP Reply\r\n"</span>);00082 <a class="code" href="group__arp.html#ga7">arpPrintHeader</a>( &packet->arp );00083 <span class="preprocessor"> #endif</span>00084 <span class="preprocessor"></span>00085 <span class="comment">// send reply!</span>00086 <a class="code" href="group__nic.html#ga1">nicSend</a>(len, (<span class="keywordtype">unsigned</span> <span class="keywordtype">char</span>*)packet);00087 }00088 }00089 <a name="l00090"></a><a class="code" href="group__arp.html#ga3">00090</a> <span class="keywordtype">void</span> <a class="code" href="group__arp.html#ga3">arpIpIn</a>(<span class="keyword">struct</span> netEthIpHeader* packet)00091 {00092 int8_t index;00093 00094 <span class="comment">// check if sender is already present in arp table</span>00095 index = <a class="code" href="group__arp.html#ga6">arpMatchIp</a>(<a class="code" href="group__net.html#ga34">HTONL</a>(packet->ip.srcipaddr));00096 <span class="keywordflow">if</span>(index != -1)00097 {00098 <span class="comment">// sender's IP address found, update ARP entry</span>00099 ArpTable[index].ethaddr = packet->eth.src;00100 <span class="comment">// and we're done</span>00101 <span class="keywordflow">return</span>;00102 }00103 00104 <span class="comment">// sender was not present in table,</span>00105 <span class="comment">// must add in empty/expired slot</span>00106 <span class="keywordflow">for</span>(index=0; index<ARP_TABLE_SIZE; index++)00107 {00108 <span class="keywordflow">if</span>(!ArpTable[index].time)00109 {00110 <span class="comment">// write entry</span>00111 ArpTable[index].ethaddr = packet->eth.src;00112 ArpTable[index].ipaddr = <a class="code" href="group__net.html#ga34">HTONL</a>(packet->ip.srcipaddr);⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -