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最新的免费嵌入式系统TCP/IP协议栈！

<a name="l00207"></a>00207       }
<a name="l00208"></a>00208     }
<a name="l00209"></a>00209     i = c;
<a name="l00210"></a>00210     tabptr = &amp;arp_table[i];
<a name="l00211"></a>00211   }
<a name="l00212"></a>00212 
<a name="l00213"></a>00213   <span class="comment">/* Now, i is the ARP table entry which we will fill with the new</span>
<a name="l00214"></a>00214 <span class="comment">     information. */</span>
<a name="l00215"></a>00215   memcpy(tabptr-&gt;ipaddr, ipaddr, 4);
<a name="l00216"></a>00216   memcpy(tabptr-&gt;ethaddr.addr, ethaddr-&gt;<a class="code" href="a00089.html#aacd5fa1806e0f0dd0bc96dd36507ad8">addr</a>, 6);
<a name="l00217"></a>00217   tabptr-&gt;time = arptime;
<a name="l00218"></a>00218 }
<a name="l00219"></a>00219 <span class="comment">/*-----------------------------------------------------------------------------------*/</span><span class="comment"></span>
<a name="l00220"></a>00220 <span class="comment">/**</span>
<a name="l00221"></a>00221 <span class="comment"> * ARP processing for incoming IP packets</span>
<a name="l00222"></a>00222 <span class="comment"> *</span>
<a name="l00223"></a>00223 <span class="comment"> * This function should be called by the device driver when an IP</span>
<a name="l00224"></a>00224 <span class="comment"> * packet has been received. The function will check if the address is</span>
<a name="l00225"></a>00225 <span class="comment"> * in the ARP cache, and if so the ARP cache entry will be</span>
<a name="l00226"></a>00226 <span class="comment"> * refreshed. If no ARP cache entry was found, a new one is created.</span>
<a name="l00227"></a>00227 <span class="comment"> *</span>
<a name="l00228"></a>00228 <span class="comment"> * This function expects an IP packet with a prepended Ethernet header</span>
<a name="l00229"></a>00229 <span class="comment"> * in the uip_buf[] buffer, and the length of the packet in the global</span>
<a name="l00230"></a>00230 <span class="comment"> * variable uip_len.</span>
<a name="l00231"></a>00231 <span class="comment"> */</span>
<a name="l00232"></a>00232 <span class="comment">/*-----------------------------------------------------------------------------------*/</span>
<a name="l00233"></a>00233 <span class="preprocessor">#if 0</span>
<a name="l00234"></a>00234 <span class="preprocessor"></span><span class="keywordtype">void</span>
<a name="l00235"></a>00235 <a class="code" href="a00152.html#g737337d6a51e31b236c8233d024138a8">uip_arp_ipin</a>(<span class="keywordtype">void</span>)
<a name="l00236"></a>00236 {
<a name="l00237"></a>00237   <a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> -= <span class="keyword">sizeof</span>(<span class="keyword">struct </span><a class="code" href="a00090.html">uip_eth_hdr</a>);
<a name="l00238"></a>00238         
<a name="l00239"></a>00239   <span class="comment">/* Only insert/update an entry if the source IP address of the</span>
<a name="l00240"></a>00240 <span class="comment">     incoming IP packet comes from a host on the local network. */</span>
<a name="l00241"></a>00241   <span class="keywordflow">if</span>((<a class="code" href="a00152.html#g9f2196e2705036869611962425e404bf">IPBUF</a>-&gt;srcipaddr[0] &amp; <a class="code" href="a00150.html#g3237be0d9ec457de0177689ee23c0d5c">uip_netmask</a>[0]) !=
<a name="l00242"></a>00242      (<a class="code" href="a00150.html#g7d3673f52f5846b6961d23b150decd54">uip_hostaddr</a>[0] &amp; <a class="code" href="a00150.html#g3237be0d9ec457de0177689ee23c0d5c">uip_netmask</a>[0])) {
<a name="l00243"></a>00243     <span class="keywordflow">return</span>;
<a name="l00244"></a>00244   }
<a name="l00245"></a>00245   <span class="keywordflow">if</span>((<a class="code" href="a00152.html#g9f2196e2705036869611962425e404bf">IPBUF</a>-&gt;srcipaddr[1] &amp; uip_netmask[1]) !=
<a name="l00246"></a>00246      (<a class="code" href="a00150.html#g7d3673f52f5846b6961d23b150decd54">uip_hostaddr</a>[1] &amp; uip_netmask[1])) {
<a name="l00247"></a>00247     <span class="keywordflow">return</span>;
<a name="l00248"></a>00248   }
<a name="l00249"></a>00249   uip_arp_update(<a class="code" href="a00152.html#g9f2196e2705036869611962425e404bf">IPBUF</a>-&gt;srcipaddr, &amp;(<a class="code" href="a00152.html#g9f2196e2705036869611962425e404bf">IPBUF</a>-&gt;ethhdr.src));
<a name="l00250"></a>00250   
<a name="l00251"></a>00251   <span class="keywordflow">return</span>;
<a name="l00252"></a>00252 }
<a name="l00253"></a>00253 <span class="preprocessor">#endif </span><span class="comment">/* 0 */</span>
<a name="l00254"></a>00254 <span class="comment">/*-----------------------------------------------------------------------------------*/</span><span class="comment"></span>
<a name="l00255"></a>00255 <span class="comment">/**</span>
<a name="l00256"></a>00256 <span class="comment"> * ARP processing for incoming ARP packets.</span>
<a name="l00257"></a>00257 <span class="comment"> *</span>
<a name="l00258"></a>00258 <span class="comment"> * This function should be called by the device driver when an ARP</span>
<a name="l00259"></a>00259 <span class="comment"> * packet has been received. The function will act differently</span>
<a name="l00260"></a>00260 <span class="comment"> * depending on the ARP packet type: if it is a reply for a request</span>
<a name="l00261"></a>00261 <span class="comment"> * that we previously sent out, the ARP cache will be filled in with</span>
<a name="l00262"></a>00262 <span class="comment"> * the values from the ARP reply. If the incoming ARP packet is an ARP</span>
<a name="l00263"></a>00263 <span class="comment"> * request for our IP address, an ARP reply packet is created and put</span>
<a name="l00264"></a>00264 <span class="comment"> * into the uip_buf[] buffer.</span>
<a name="l00265"></a>00265 <span class="comment"> *</span>
<a name="l00266"></a>00266 <span class="comment"> * When the function returns, the value of the global variable uip_len</span>
<a name="l00267"></a>00267 <span class="comment"> * indicates whether the device driver should send out a packet or</span>
<a name="l00268"></a>00268 <span class="comment"> * not. If uip_len is zero, no packet should be sent. If uip_len is</span>
<a name="l00269"></a>00269 <span class="comment"> * non-zero, it contains the length of the outbound packet that is</span>
<a name="l00270"></a>00270 <span class="comment"> * present in the uip_buf[] buffer.</span>
<a name="l00271"></a>00271 <span class="comment"> *</span>
<a name="l00272"></a>00272 <span class="comment"> * This function expects an ARP packet with a prepended Ethernet</span>
<a name="l00273"></a>00273 <span class="comment"> * header in the uip_buf[] buffer, and the length of the packet in the</span>
<a name="l00274"></a>00274 <span class="comment"> * global variable uip_len.</span>
<a name="l00275"></a>00275 <span class="comment"> */</span>
<a name="l00276"></a>00276 <span class="comment">/*-----------------------------------------------------------------------------------*/</span>
<a name="l00277"></a>00277 <span class="keywordtype">void</span>
<a name="l00278"></a><a class="code" href="a00152.html#g902c4a360134096224bc2655f623aa5f">00278</a> <a class="code" href="a00152.html#g902c4a360134096224bc2655f623aa5f">uip_arp_arpin</a>(<span class="keywordtype">void</span>)
<a name="l00279"></a>00279 {
<a name="l00280"></a>00280   
<a name="l00281"></a>00281   <span class="keywordflow">if</span>(<a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> &lt; <span class="keyword">sizeof</span>(<span class="keyword">struct</span> arp_hdr)) {
<a name="l00282"></a>00282     <a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> = 0;
<a name="l00283"></a>00283     <span class="keywordflow">return</span>;
<a name="l00284"></a>00284   }
<a name="l00285"></a>00285   <a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> = 0;
<a name="l00286"></a>00286   
<a name="l00287"></a>00287   <span class="keywordflow">switch</span>(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;opcode) {
<a name="l00288"></a>00288   <span class="keywordflow">case</span> <a class="code" href="a00148.html#g69a7a4951ff21b302267532c21ee78fc">HTONS</a>(<a class="code" href="a00152.html#g7a7c46ffaba30477b8c9e3e61bd2e106">ARP_REQUEST</a>):
<a name="l00289"></a>00289     <span class="comment">/* ARP request. If it asked for our address, we send out a</span>
<a name="l00290"></a>00290 <span class="comment">       reply. */</span>
<a name="l00291"></a>00291     <span class="keywordflow">if</span>(<a class="code" href="a00148.html#g210e629f7252e4bc8458cbdf260b3318">uip_ipaddr_cmp</a>(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;dipaddr, <a class="code" href="a00150.html#g7d3673f52f5846b6961d23b150decd54">uip_hostaddr</a>)) {
<a name="l00292"></a>00292       <span class="comment">/* First, we register the one who made the request in our ARP</span>
<a name="l00293"></a>00293 <span class="comment">         table, since it is likely that we will do more communication</span>
<a name="l00294"></a>00294 <span class="comment">         with this host in the future. */</span>
<a name="l00295"></a>00295       uip_arp_update(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;sipaddr, &amp;<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;shwaddr);
<a name="l00296"></a>00296       
<a name="l00297"></a>00297       <span class="comment">/* The reply opcode is 2. */</span>
<a name="l00298"></a>00298       <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;opcode = <a class="code" href="a00148.html#g69a7a4951ff21b302267532c21ee78fc">HTONS</a>(2);
<a name="l00299"></a>00299 
<a name="l00300"></a>00300       memcpy(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;dhwaddr.addr, <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;shwaddr.addr, 6);
<a name="l00301"></a>00301       memcpy(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;shwaddr.addr, <a class="code" href="a00150.html#g499bb98a0b4ae9a98553ede81317606d">uip_ethaddr</a>.<a class="code" href="a00089.html#aacd5fa1806e0f0dd0bc96dd36507ad8">addr</a>, 6);
<a name="l00302"></a>00302       memcpy(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ethhdr.src.addr, <a class="code" href="a00150.html#g499bb98a0b4ae9a98553ede81317606d">uip_ethaddr</a>.<a class="code" href="a00089.html#aacd5fa1806e0f0dd0bc96dd36507ad8">addr</a>, 6);
<a name="l00303"></a>00303       memcpy(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ethhdr.dest.addr, <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;dhwaddr.addr, 6);
<a name="l00304"></a>00304       
<a name="l00305"></a>00305       <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;dipaddr[0] = <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;sipaddr[0];
<a name="l00306"></a>00306       <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;dipaddr[1] = <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;sipaddr[1];
<a name="l00307"></a>00307       <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;sipaddr[0] = <a class="code" href="a00150.html#g7d3673f52f5846b6961d23b150decd54">uip_hostaddr</a>[0];
<a name="l00308"></a>00308       <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;sipaddr[1] = <a class="code" href="a00150.html#g7d3673f52f5846b6961d23b150decd54">uip_hostaddr</a>[1];
<a name="l00309"></a>00309 
<a name="l00310"></a>00310       <a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;ethhdr.type = <a class="code" href="a00148.html#g69a7a4951ff21b302267532c21ee78fc">HTONS</a>(<a class="code" href="a00152.html#g3e1562e8a6de32268e5df92a52152f91">UIP_ETHTYPE_ARP</a>);
<a name="l00311"></a>00311       <a class="code" href="a00149.html#g12a33f0c09711167bdf3dd7d7cf8c5a1">uip_len</a> = <span class="keyword">sizeof</span>(<span class="keyword">struct </span>arp_hdr);
<a name="l00312"></a>00312     }
<a name="l00313"></a>00313     <span class="keywordflow">break</span>;
<a name="l00314"></a>00314   <span class="keywordflow">case</span> <a class="code" href="a00148.html#g69a7a4951ff21b302267532c21ee78fc">HTONS</a>(<a class="code" href="a00152.html#g06ba7b414e718081998f2814090debf1">ARP_REPLY</a>):
<a name="l00315"></a>00315     <span class="comment">/* ARP reply. We insert or update the ARP table if it was meant</span>
<a name="l00316"></a>00316 <span class="comment">       for us. */</span>
<a name="l00317"></a>00317     <span class="keywordflow">if</span>(<a class="code" href="a00148.html#g210e629f7252e4bc8458cbdf260b3318">uip_ipaddr_cmp</a>(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;dipaddr, <a class="code" href="a00150.html#g7d3673f52f5846b6961d23b150decd54">uip_hostaddr</a>)) {
<a name="l00318"></a>00318       uip_arp_update(<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;sipaddr, &amp;<a class="code" href="a00150.html#g24f52ac52d6e714cb04a5aa01be3bdd0">BUF</a>-&gt;shwaddr);
<a name="l00319"></a>00319     }