{"id":88,"date":"2014-03-09T16:16:24","date_gmt":"2014-03-09T16:16:24","guid":{"rendered":""},"modified":"2014-03-09T16:16:24","modified_gmt":"2014-03-09T16:16:24","slug":"","status":"publish","type":"post","link":"http:\/\/weizn.net\/?p=88","title":{"rendered":"Linux\u539f\u59cb\u5957\u63a5\u5b57\u5b9e\u73b0\u5206\u6790"},"content":{"rendered":"
<p>\n\thttp:\/\/blog.chinaunix.net\/uid-27074062-id-3388166.html<br \/>\n<span><span><span style="font-family:\u6977\u4f53_gb2312;"> <\/span><\/span><\/span>\n<\/p>\n<p>\n\t<span><span><span style="font-family:\u6977\u4f53_gb2312;">\u672c\u6587\u4ece<span>IPV4<\/span>\u534f\u8bae\u6808\u539f\u59cb\u5957\u63a5\u5b57\u7684\u5206\u7c7b\u5165\u624b\uff0c\u8be6\u7ec6\u4ecb\u7ecd\u4e86\u94fe\u8def\u5c42\u548c\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u7684\u7279\u70b9\u53ca\u5176\u5185\u6838\u5b9e\u73b0\u7ec6\u8282\u3002\u5e76\u7ed3\u5408\u539f\u59cb\u5957\u63a5\u5b57\u7684\u5b9e\u9645\u5e94\u7528\uff0c\u8bf4\u660e\u5404\u7c7b\u578b\u539f\u59cb\u5957\u63a5\u5b57\u7684\u9002\u5e94\u8303\u56f4\uff0c\u4ee5\u53ca\u5728\u5b9e\u9645\u4f7f\u7528\u65f6\u9700\u8981\u6ce8\u610f\u7684\u95ee\u9898\u3002<span> <\/span><\/span><\/span><\/span> <span><span><span style="line-height:240%;font-family:\u5b8b\u4f53;font-size:14pt;">\u4e00\u3001\u539f\u59cb\u5957\u63a5\u5b57\u6982\u8ff0<\/span><\/span><\/span><span><span><span style="line-height:240%;font-size:14pt;"> <\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><a name="OLE_LINK25"><\/a><a name="OLE_LINK24"><\/a><span><span style="font-family:\u5b8b\u4f53;"><span>\u534f\u8bae\u6808\u7684\u539f\u59cb\u5957\u63a5\u5b57\u4ece\u5b9e\u73b0\u4e0a\u53ef\u4ee5\u5206\u4e3a\u201c\u94fe\u8def\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u201d\u548c\u201c\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u201d\u4e24\u5927\u7c7b\u3002\u672c\u8282\u4e3b\u8981\u63cf\u8ff0\u5404\u81ea\u7684\u7279\u70b9\u53ca\u5176\u9002\u7528\u8303\u56f4\u3002<\/span><\/span><\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span><span><span style="font-family:\u5b8b\u4f53;">\u94fe\u8def\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u53ef\u4ee5\u76f4\u63a5\u7528\u4e8e\u63a5\u6536\u548c\u53d1\u9001\u94fe\u8def\u5c42\u7684<\/span><span>MAC<\/span><\/span><\/span><\/span><\/span><span><span><span><span><span style="font-family:\u5b8b\u4f53;">\u5e27\uff0c\u5728\u53d1\u9001\u65f6\u9700\u8981\u7531\u8c03\u7528\u8005\u81ea\u884c\u6784\u9020\u548c\u5c01\u88c5<\/span><span>MAC<\/span><\/span><\/span><\/span><\/span><span><span><span><span><span style="font-family:\u5b8b\u4f53;">\u9996\u90e8\u3002\u800c\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u53ef\u4ee5\u76f4\u63a5\u7528\u4e8e\u63a5\u6536\u548c\u53d1\u9001<\/span><span>IP<\/span><\/span><\/span><\/span><\/span><span><span><span><span><span style="font-family:\u5b8b\u4f53;">\u5c42\u7684\u62a5\u6587\u6570\u636e\uff0c\u5728\u53d1\u9001\u65f6\u9700\u8981\u81ea\u884c\u6784\u9020<\/span><span>IP<\/span><\/span><\/span><\/span><\/span><span><span><span><span><span style="font-family:\u5b8b\u4f53;">\u62a5\u6587\u5934\uff08\u53d6\u51b3\u662f\u5426\u8bbe\u7f6e<\/span><span>IP_HDRINCL<\/span><\/span><\/span><\/span><\/span><span><span><span><span><span style="font-family:\u5b8b\u4f53;">\u9009\u9879\uff09\u3002<\/span><\/span><\/span><\/span><\/span>\n<\/p>\n<p><span><\/span><span><\/span> <\/p>\n<p class="MsoNormal">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p>\n\t<span><span><span style="line-height:173%;font-size:12pt;">1.1 <span> <\/span><\/span><\/span><\/span><span><span><span style="line-height:173%;font-family:\u5b8b\u4f53;font-size:12pt;">\u94fe\u8def\u5c42\u539f\u59cb\u5957\u63a5\u5b57<\/span><\/span><\/span><span><span><span style="line-height:173%;font-size:12pt;"> <\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span style="font-family:\u5b8b\u4f53;">\u94fe\u8def\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u8c03\u7528<\/span><span>socket()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u51fd\u6570\u521b\u5efa\u3002\u7b2c\u4e00\u4e2a\u53c2\u6570\u6307\u5b9a\u534f\u8bae\u65cf\u7c7b\u578b\u4e3a<\/span><a name="OLE_LINK2"><\/a><a name="OLE_LINK1"><\/a><span><span><span>PF_PACKET<\/span><\/span><\/span><\/span><\/span><span><\/span><span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\uff0c\u7b2c\u4e8c\u4e2a\u53c2\u6570<\/span><span>type<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u53ef\u4ee5\u8bbe\u7f6e\u4e3a<\/span><span>SOCK_RAW<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6216<\/span><span>SOCK_DGRAM<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\uff0c\u7b2c\u4e09\u4e2a\u53c2\u6570\u662f\u534f\u8bae\u7c7b\u578b\uff08\u8be5\u53c2\u6570\u53ea\u5bf9\u62a5\u6587\u63a5\u6536\u6709\u610f\u4e49\uff09\u3002\u534f\u8bae\u7c7b\u578b<\/span><span>protocol<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e0d\u540c\u53d6\u503c\u7684\u610f\u4e49\u5177\u4f53\u89c1\u8868<\/span><span>1<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6240\u793a\uff1a<\/span><\/span><\/span><span><span><a name="OLE_LINK6"><\/a><\/span><\/span>\n<\/p>\n<p><a name="OLE_LINK6"><\/a> <\/p>\n<div>\n<div id="code359" class="codeText">\n<ol class="dp-css">\n<li>\n\t\t\t\t<span style="color:#000000;">socket<span style="color:#0000cc;">(<\/span>PF_PACKET<span style="color:#0000cc;">,<\/span> type<span style="color:#0000cc;">,<\/span> htons<span style="color:#0000cc;">(<\/span>protocol<span style="color:#0000cc;">)<\/span><span style="color:#0000cc;">)<\/span><\/span>\n\t\t\t<\/li>\n<\/ol><\/div>\n<\/div>\n<p class="MsoNormal">\n\t<span><span><span><span>       <\/span><\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:-18pt;margin-left:18pt;" class="MsoListParagraph">\n\t<span><span><span><span>a)<span style="line-height:normal;font-style:normal;font-size:7pt;font-weight:normal;">       <\/span><\/span><\/span><span style="font-family:\u5b8b\u4f53;">\u53c2\u6570<\/span><span>type<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u8bbe\u7f6e\u4e3a<\/span><a name="OLE_LINK8"><\/a><a name="OLE_LINK7"><\/a><span><span><span>SOCK_RAW<\/span><\/span><\/span><\/span><\/span><span><\/span><span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u65f6\uff0c\u5957\u63a5\u5b57\u63a5\u6536\u548c\u53d1\u9001\u7684\u6570\u636e\u90fd\u662f\u4ece<\/span><span>MAC<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u9996\u90e8\u5f00\u59cb\u7684\u3002\u5728\u53d1\u9001\u65f6\u9700\u8981\u7531\u8c03\u7528\u8005\u4ece<\/span><span>MAC<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u9996\u90e8\u5f00\u59cb\u6784\u9020\u548c\u5c01\u88c5\u62a5\u6587\u6570\u636e\u3002<\/span><span>type<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u8bbe\u7f6e\u4e3a<\/span><span>SOCK_RAW<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7684\u60c5\u51b5\u5e94\u7528\u662f\u6bd4\u8f83\u591a\u7684\uff0c\u56e0\u4e3a\u67d0\u4e9b\u9879\u76ee\u4f1a\u4f7f\u7528\u5230\u81ea\u5b9a\u4e49\u7684\u4e8c\u5c42\u62a5\u6587\u7c7b\u578b\u3002<\/span><\/span><\/span><span><span><span><\/span><\/span><\/span>\n<\/p>\n<div>\n<div id="code781" class="codeText">\n<ol class="dp-css">\n<li>\n\t\t\t\t<span style="color:#000000;">socket<span style="color:#0000cc;">(<\/span>PF_PACKET<span style="color:#0000cc;">,<\/span> SOCK_RAW<span style="color:#0000cc;">,<\/span> htons<span style="color:#0000cc;">(<\/span>protocol<span style="color:#0000cc;">)<\/span><span style="color:#0000cc;">)<\/span><\/span>\n\t\t\t<\/li>\n<\/ol><\/div>\n<\/div>\n<p style="text-indent:18pt;" class="MsoNormal">\n\t<a href="http:\/\/blog.chinaunix.net\/attachment\/201210\/27\/27074062_13513446786lLy.jpg" target="_blank"><img title="1" alt="1" src="http:\/\/blog.chinaunix.net\/attachment\/201210\/27\/27074062_1351344679PO44.jpg" border="0" height="41" width="224" \/><\/a>\n<\/p>\n<p style="text-indent:-18pt;margin-left:18pt;" class="MsoListParagraph">\n\t<span><span><span><span>b)<span style="line-height:normal;font-style:normal;font-size:7pt;font-weight:normal;">      <\/span><\/span><\/span><span style="font-family:\u5b8b\u4f53;">\u53c2\u6570<\/span><span>type<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u8bbe\u7f6e\u4e3a<\/span><a name="OLE_LINK10"><\/a><a name="OLE_LINK9"><\/a><span><span><span>SOCK_DGRAM<\/span><\/span><\/span><\/span><\/span><span><\/span><span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u65f6\uff0c\u5957\u63a5\u5b57\u63a5\u6536\u5230\u7684\u6570\u636e\u62a5\u6587\u4f1a\u5c06<\/span><span>MAC<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u9996\u90e8\u53bb\u6389\u3002\u540c\u65f6\u5728\u53d1\u9001\u65f6\u4e5f\u4e0d\u9700\u8981\u518d\u624b\u52a8\u6784\u9020<\/span><span>MAC<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u9996\u90e8\uff0c\u53ea\u9700\u8981\u4ece<\/span><span>IP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u9996\u90e8\uff08\u6216<\/span><span>ARP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u9996\u90e8\uff0c\u53d6\u51b3\u4e8e\u5c01\u88c5\u7684\u62a5\u6587\u7c7b\u578b\uff09\u5f00\u59cb\u6784\u9020\u5373\u53ef\uff0c\u800c<\/span><span>MAC<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u9996\u90e8\u7684\u586b\u5145\u7531\u5185\u6838\u5b9e\u73b0\u7684\u3002\u82e5\u5bf9\u4e8e<\/span><span>MAC<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u9996\u90e8\u4e0d\u5173\u5fc3\u7684\u573a\u666f\uff0c\u53ef\u4ee5\u4f7f\u7528\u8fd9\u79cd\u7c7b\u578b\uff0c\u8fd9\u79cd\u7528\u6cd5\u7528\u5f97\u6bd4\u8f83\u5c11\u3002<\/span><\/span><\/span><span><span><span><\/span><\/span><\/span>\n<\/p>\n<div>\n<div id="code15" class="codeText">\n<ol class="dp-css">\n<li>\n\t\t\t\t<span style="color:#000000;">socket<span style="color:#0000cc;">(<\/span>PF_PACKET<span style="color:#0000cc;">,<\/span> SOCK_DGRAM<span style="color:#0000cc;">,<\/span> htons<span style="color:#0000cc;">(<\/span>protocol<span style="color:#0000cc;">)<\/span><span style="color:#0000cc;">)<\/span><\/span>\n\t\t\t<\/li>\n<\/ol><\/div>\n<\/div>\n<p style="text-indent:18pt;" class="MsoNormal">\n\t<span><span><span>      <a href="http:\/\/blog.chinaunix.net\/attachment\/201210\/27\/27074062_1351344679TFO0.jpg" target="_blank"><img title="1" alt="1" src="http:\/\/blog.chinaunix.net\/attachment\/201210\/27\/27074062_13513446800Im6.jpg" border="0" height="41" width="224" \/><\/a><\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:18pt;" class="MsoNormal">\n\t<span><span><span><\/span><\/span><\/span> \n<\/p>\n<p style="text-indent:18pt;" class="MsoNormal">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t<span><span><span style="font-family:\u5b8b\u4f53;font-size:9pt;">\u8868<\/span><\/span><\/span><span><span><span style="font-size:9pt;">1<span>  <\/span>protocol<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;font-size:9pt;">\u4e0d\u540c\u53d6\u503c<\/span><\/span><\/span><span><span><span style="font-size:9pt;"> <\/span><\/span><\/span>\n<\/p>\n<p><span><span><span><\/span> <\/p>\n<p class="MsoNormal" align="center">\n\t\n<\/p>\n<table cellpadding="2" cellspacing="0" border="2" width="623">\n<tbody>\n<tr>\n<td valign="top" width="132">\n\t\t\t\t<strong> <\/p>\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t<span><span><b><span style="font-size:9pt;">protocol <\/span><\/b><\/span><\/span>\n\t\t\t\t<\/p>\n<p><\/strong>\n\t\t\t<\/td>\n<td valign="top" width="132">\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t<span><span><b><span style="font-size:9pt;">\u503c<\/span><\/b><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n<td valign="top" width="355">\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t<span><span><b><span style="font-size:9pt;">\u4f5c\u7528<\/span><\/b><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n<\/tr>\n<tr>\n<td valign="top" width="132">\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t<span><span><span style="font-size:9pt;">ETH_P_ALL <\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n<td valign="top" width="132">\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t<span><span><span style="font-size:9pt;"> 0x0003 <\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n<td valign="top" width="355">\n<p style="text-align:left;" class="MsoNormal" align="center">\n\t\t\t\t\t<span><span><span style="font-size:9pt;">\u62a5\u6536\u672c\u673a\u6536\u5230\u7684\u6240\u6709\u4e8c\u5c42\u62a5\u6587<\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n<\/tr>\n<tr>\n<td valign="top" width="132">\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t<span><span><span style="font-size:9pt;">ETH_P_IP<\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n<td valign="top" width="132">\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t<span><span><span style="font-size:9pt;">0x0800<\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n<td valign="top" width="355">\n<p style="text-align:left;" class="MsoNormal" align="left">\n\t\t\t\t\t<span><span><span style="font-size:9pt;">\u62a5\u6536\u672c\u673a\u6536\u5230\u7684\u6240\u6709IP\u62a5\u6587<\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n<\/tr>\n<tr>\n<td valign="top" width="132">\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t<span><span><span style="font-size:9pt;">ETH_P_ARP <\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n<td valign="top" width="132">\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t<span><span><span style="font-size:9pt;">0x0806<\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n<td valign="top" width="355">\n<p style="text-align:left;" class="MsoNormal" align="left">\n\t\t\t\t\t<span><span><span style="font-size:9pt;">\u62a5\u6536\u672c\u673a\u6536\u5230\u7684\u6240\u6709ARP\u62a5\u6587<\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n<\/tr>\n<tr>\n<td valign="top" width="132">\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t<span><span><span style="font-size:9pt;">ETH_P_RARP<\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n<td valign="top" width="132">\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t<span><span><span style="font-size:9pt;">0x8035<\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n<td valign="top" width="355">\n<p style="text-align:left;" class="MsoNormal" align="left">\n\t\t\t\t\t<span><span><span style="font-size:9pt;">\u62a5\u6536\u672c\u673a\u6536\u5230\u7684\u6240\u6709RARP\u62a5\u6587<\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n<\/tr>\n<tr>\n<td valign="top" width="132">\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t<span><span><span style="font-size:9pt;">\u81ea\u5b9a\u4e49\u534f\u8bae<\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n<td valign="top" width="132">\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t<span><span><span style="font-size:9pt;">\u6bd4\u59820x0810<\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n<td valign="top" width="355">\n<p style="text-align:left;" class="MsoNormal" align="left">\n\t\t\t\t\t<span><span><span style="font-size:9pt;">\u62a5\u6536\u672c\u673a\u6536\u5230\u7684\u6240\u6709\u7c7b\u578b\u4e3a0x0810\u7684\u4e8c\u5c42\u62a5\u6587<\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n<\/tr>\n<tr>\n<td valign="top" width="132">\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t<span><span><span style="font-size:9pt;">\u4e0d\u6307\u5b9a<\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n<td valign="top" width="132">\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t<span><span><span style="font-size:9pt;">0<\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n<td valign="top" width="355">\n<p style="text-align:left;" class="MsoNormal" align="left">\n\t\t\t\t\t<span><span><span style="font-size:9pt;">\u4e0d\u80fd\u7528\u4e8e\u63a5\u6536\uff0c\u53ea\u7528\u4e8e\u53d1\u9001<\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n<\/tr>\n<tr>\n<td valign="top" width="132">\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t<span><span><span style="font-size:9pt;">\u2026\u2026 <\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n<td valign="top" width="132">\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t<span><span><span style="font-size:9pt;">\u2026\u2026 <\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n<td valign="top" width="355">\n<p style="text-align:left;" class="MsoNormal" align="left">\n\t\t\t\t\t<span><span><span style="font-size:9pt;">\u2026\u2026<\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p><\/span><\/span> <\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span style="font-family:\u5b8b\u4f53;">\u8868<\/span><span>1<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e2d<\/span><span>protocol<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7684\u53d6\u503c\u4e2d\u6709\u4e24\u4e2a\u503c\u662f\u6bd4\u8f83\u7279\u6b8a\u7684\u3002\u5f53<\/span><span>protocol<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e3a<\/span><span>ETH_P_ALL<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u65f6\uff0c\u8868\u793a\u80fd\u591f\u63a5\u6536\u672c\u673a\u6536\u5230\u7684\u6240\u6709\u4e8c\u5c42\u62a5\u6587\uff08\u5305\u62ec<\/span><span>IP, ARP, <\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u81ea\u5b9a\u4e49\u4e8c\u5c42\u62a5\u6587\u7b49\uff09\uff0c\u540c\u65f6\u8fd9\u79cd\u7c7b\u578b\u5957\u63a5\u5b57\u8fd8\u80fd\u591f\u5c06\u5916\u53d1\u7684\u62a5\u6587\u518d\u6536\u56de\u6765\u3002\u5f53<\/span><span>protocol<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e3a<\/span><span>0<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u65f6\uff0c\u8868\u793a\u8be5\u5957\u63a5\u5b57\u4e0d\u80fd\u7528\u4e8e\u63a5\u6536\u62a5\u6587\uff0c\u53ea\u80fd\u7528\u4e8e\u53d1\u9001\u3002<a name="OLE_LINK12"><\/a><a name="OLE_LINK11"><\/a><span><span>\u5177\u4f53\u7684\u5b9e\u73b0\u7ec6\u8282\u5728<\/span><\/span><\/span><span><span><span>2.2<\/span><\/span><\/span><\/span><\/span><span><span><span><span><span style="font-family:\u5b8b\u4f53;">\u8282\u4e2d\u4f1a\u8be6\u7ec6\u4ecb\u7ecd\u3002<\/span><\/span><\/span><\/span><\/span>\n<\/p>\n<p class="MsoNormal">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p>\n\t \n<\/p>\n<p><span><span><span style="line-height:173%;font-size:12pt;">1.2 <span> <\/span><\/span><\/span><\/span><span><span><span style="line-height:173%;font-family:\u5b8b\u4f53;font-size:12pt;">\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57<\/span><\/span><\/span><span><span><span style="line-height:173%;font-size:12pt;"> <\/span><\/span><\/span> <\/p>\n<p style="text-align:left;text-indent:21pt;" class="MsoNormal" align="left">\n\t<span><span><span style="font-family:\u5b8b\u4f53;">\u521b\u5efa\u9762\u5411\u8fde\u63a5\u7684<\/span><span>TCP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u548c\u521b\u5efa\u9762\u5411\u65e0\u8fde\u63a5\u7684<\/span><span>UDP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u5957\u63a5\u5b57\uff0c\u5728\u63a5\u6536\u548c\u53d1\u9001\u65f6\u53ea\u80fd\u64cd\u4f5c\u6570\u636e\u90e8\u5206\uff0c\u800c\u4e0d\u80fd\u5bf9<\/span><span>IP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u9996\u90e8\u6216<\/span><span>TCP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u548c<\/span><span>UDP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u9996\u90e8\u8fdb\u884c\u64cd\u4f5c\u3002\u5982\u679c\u60f3\u8981\u64cd\u4f5c<\/span><span>IP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u9996\u90e8\u6216\u4f20\u8f93\u5c42\u534f\u8bae\u9996\u90e8\uff0c\u5c31\u9700\u8981\u8c03\u7528\u5982\u4e0b<\/span><span>socket()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u51fd\u6570\u521b\u5efa\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u3002\u7b2c\u4e00\u4e2a\u53c2\u6570\u6307\u5b9a\u534f\u8bae\u65cf\u7684\u7c7b\u578b\u4e3a<\/span><span>PF_INET<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\uff0c\u7b2c\u4e8c\u4e2a\u53c2\u6570\u4e3a<\/span><span>SOCK_RAW<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\uff0c\u7b2c\u4e09\u4e2a\u53c2\u6570<\/span><span>protocol<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e3a\u534f\u8bae\u7c7b\u578b\uff08\u4e0d\u540c\u53d6\u503c\u7684\u610f\u4e49\u89c1\u8868<\/span><span>2<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\uff09\u3002\u4ea7\u54c1\u7ebf\u6709\u4f7f\u7528<\/span><span>OSPF<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u548c<\/span><span>RSVP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7b49\u534f\u8bae\uff0c\u9700\u8981\u4f7f\u7528\u8fd9\u79cd\u7c7b\u578b\u7684\u5957\u63a5\u5b57\u3002<\/span><\/span><\/span><span><span><a name="OLE_LINK4"><\/a><\/span><\/span>\n<\/p>\n<p><a name="OLE_LINK4"><\/a> <\/p>\n<div>\n\t<a name="OLE_LINK4"><\/a> <\/p>\n<div id="code593" class="codeText">\n<ol class="dp-css">\n<li>\n\t\t\t\t<span style="color:#000000;">socktet<span style="color:#0000cc;">(<\/span>PF_INET<span style="color:#0000cc;">,<\/span> SOCK_RAW<span style="color:#0000cc;">,<\/span> protocol<span style="color:#0000cc;">)<\/span><\/span>\n\t\t\t<\/li>\n<\/ol><\/div>\n<p><span><span><span><span>    <\/span><\/span><\/span><\/span>\n<\/div>\n<p style="text-indent:-18pt;margin-left:18pt;" class="MsoListParagraph">\n\t<span><span><span><span>a)<span style="line-height:normal;font-style:normal;font-size:7pt;font-weight:normal;">       <\/span><\/span><\/span><span style="font-family:\u5b8b\u4f53;">\u63a5\u6536\u62a5\u6587<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:3pt;margin-left:18pt;" class="MsoNormal">\n\t<span><span><span style="font-family:\u5b8b\u4f53;">\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u63a5\u6536\u5230\u7684\u62a5\u6587\u6570\u636e\u662f\u4ece<\/span><span>IP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u9996\u90e8\u5f00\u59cb\u7684\uff0c\u5373\u63a5\u6536\u5230\u7684\u6570\u636e\u5305\u542b\u4e86<\/span><span>IP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u9996\u90e8<\/span><span>, TCP\/UDP\/ICMP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7b49\u9996\u90e8<\/span><span>, <\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4ee5\u53ca\u6570\u636e\u90e8\u5206\u3002<\/span><\/span><\/span>\n<\/p>\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p class="MsoNormal">\n\t<span><span><span><span>      <a href="http:\/\/blog.chinaunix.net\/attachment\/201210\/27\/27074062_1351344680kxKw.jpg" target="_blank"><img title="1" alt="1" src="http:\/\/blog.chinaunix.net\/attachment\/201210\/27\/27074062_13513446813d44.jpg" border="0" height="36" width="244" \/><\/a> <\/span><\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:-18pt;margin-left:18pt;" class="MsoListParagraph">\n\t<span><span><span><span>b)<span style="line-height:normal;font-style:normal;font-size:7pt;font-weight:normal;">      <\/span><\/span><\/span><span style="font-family:\u5b8b\u4f53;">\u53d1\u9001\u62a5\u6587<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:-0.3pt;margin-left:21.3pt;" class="MsoNormal">\n\t<span><span><span style="font-family:\u5b8b\u4f53;">\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u53d1\u9001\u7684\u62a5\u6587\u6570\u636e\uff0c\u5728\u9ed8\u8ba4\u60c5\u51b5\u4e0b\u662f\u4ece<\/span><span>IP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u9996\u90e8\u4e4b\u540e\u5f00\u59cb\u7684\uff0c\u5373\u9700\u8981\u7531\u8c03\u7528\u8005\u81ea\u884c\u6784\u9020\u548c\u5c01\u88c5<\/span><span>TCP\/UDP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7b49\u534f\u8bae\u9996\u90e8\u3002<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:-0.3pt;margin-left:21.3pt;" class="MsoNormal">\n\t<span><span><span style="font-family:\u5b8b\u4f53;"><a href="http:\/\/blog.chinaunix.net\/attachment\/201210\/27\/27074062_135134468451Mc.jpg" target="_blank"><img title="1" alt="1" src="http:\/\/blog.chinaunix.net\/attachment\/201210\/27\/27074062_13513446851glU.jpg" border="0" height="36" width="244" \/><\/a> <\/span><\/span><\/span>\n<\/p>\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p style="margin-left:21pt;" class="MsoNormal">\n\t<span><span><span style="font-family:\u5b8b\u4f53;">\u8fd9\u79cd\u5957\u63a5\u5b57\u4e5f\u63d0\u4f9b\u4e86\u53d1\u9001\u65f6\u4ece<\/span><span>IP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u9996\u90e8\u5f00\u59cb\u6784\u9020\u6570\u636e\u7684\u529f\u80fd\uff0c\u901a\u8fc7<\/span><span>setsockopt()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7ed9\u5957\u63a5\u5b57\u8bbe\u7f6e\u4e0a<\/span><span>IP_HDRINCL<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u9009\u9879\uff0c\u5c31\u9700\u8981\u5728\u53d1\u9001\u65f6\u81ea\u884c\u6784\u9020<\/span><span>IP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u9996\u90e8\u3002<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t\n<\/p>\n<table cellpadding="0" cellspacing="0" width="100%">\n<tbody>\n<tr>\n<td>\n<div>\n<p style="text-indent:21pt;" class="MsoNormal" align="left">\n\t\t\t\t\t\t<span style="font-size:9pt;">   <\/span>\n\t\t\t\t\t<\/p>\n<div>\n<div id="code546" class="codeText">\n<ol class="dp-css">\n<li>\n\t\t\t\t\t\t\t\t\t<span style="color:#000000;"><span style="color:#ff0000;">int<\/span> val <span style="color:#0000cc;">=<\/span> 1<span style="color:#0000cc;">;<\/span> <br \/>\n<\/span>\n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\tsetsockopt <span style="color:#0000cc;">(<\/span>sockfd<span style="color:#0000cc;">,<\/span> IPPROTO_IP<span style="color:#0000cc;">,<\/span> IP_HDRINCL<span style="color:#0000cc;">,<\/span> <span style="color:#0000cc;">&<\/span>val<span style="color:#0000cc;">,<\/span> sizeof<span style="color:#0000cc;">(<\/span>val<span style="color:#0000cc;">)<\/span><span style="color:#0000cc;">)<\/span><span style="color:#0000cc;">;<\/span>\n\t\t\t\t\t\t\t\t<\/li>\n<\/ol><\/div>\n<p><span style="font-size:9pt;"><\/span>\n\t\t\t\t\t<\/div>\n<\/p><\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t<span><span><span style="font-family:\u5b8b\u4f53;font-size:9pt;">\u8868<\/span><\/span><\/span><span><span><span style="font-size:9pt;">2<span>  <\/span>protocol<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;font-size:9pt;">\u4e0d\u540c\u53d6<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;"><\/span><\/span><\/span>\n<\/p>\n<div align="center">\n<table cellpadding="2" cellspacing="0" align="center" border="2" width="623">\n<tbody>\n<tr>\n<td valign="top" width="132">\n\t\t\t\t\t<strong> <\/p>\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t\t<span><span><b><span style="font-size:9pt;">protocol <\/span><\/b><\/span><\/span>\n\t\t\t\t\t<\/p>\n<p><\/strong>\n\t\t\t\t<\/td>\n<td valign="top" width="132">\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t\t<span><span><b><span style="font-size:9pt;">\u503c<\/span><\/b><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n<td valign="top" width="355">\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t\t<span><span><b><span style="font-size:9pt;">\u4f5c\u7528<\/span><\/b><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n<\/tr>\n<tr>\n<td valign="top" width="132">\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t\t<span><span><span style="font-size:9pt;">IPPROTO_TCP <\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n<td valign="top" width="132">\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t\t<span><span><span style="font-size:9pt;">6<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n<td valign="top" width="355">\n<p style="text-align:left;" class="MsoNormal" align="center">\n\t\t\t\t\t\t<span><span><span style="font-size:9pt;">\u62a5\u6536TCP\u7c7b\u578b\u7684\u62a5\u6587<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n<\/tr>\n<tr>\n<td valign="top" width="132">\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t\t<span><span><span style="font-size:9pt;">IPPROTO_UDP<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n<td valign="top" width="132">\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t\t<span><span><span style="font-size:9pt;">17<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n<td valign="top" width="355">\n<p style="text-align:left;" class="MsoNormal" align="left">\n\t\t\t\t\t\t<span><span><span style="font-size:9pt;">\u62a5\u6536UDP\u7c7b\u578b\u7684\u62a5\u6587<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n<\/tr>\n<tr>\n<td valign="top" width="132">\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t\t<span><span><span style="font-size:9pt;">IPPROTO_ICMP <\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n<td valign="top" width="132">\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t\t<span><span><span style="font-size:9pt;">1<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n<td valign="top" width="355">\n<p style="text-align:left;" class="MsoNormal" align="left">\n\t\t\t\t\t\t<span><span><span style="font-size:9pt;">\u62a5\u6536ICMP\u7c7b\u578b\u7684\u62a5\u6587<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n<\/tr>\n<tr>\n<td valign="top" width="132">\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t\t<span><span><span style="font-size:9pt;">IPPROTO_IGMP<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n<td valign="top" width="132">\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t\t<span><span><span style="font-size:9pt;">2<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n<td valign="top" width="355">\n<p style="text-align:left;" class="MsoNormal" align="left">\n\t\t\t\t\t\t<span><span><span style="font-size:9pt;">\u62a5\u6536IGMP\u7c7b\u578b\u7684\u62a5\u6587<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n<\/tr>\n<tr>\n<td valign="top" width="132">\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t\t<span><span><span style="font-size:9pt;">IPPROTO_RAW<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n<td valign="top" width="132">\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t\t<span><span><span style="font-size:9pt;">255<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n<td valign="top" width="355">\n<p style="text-align:left;" class="MsoNormal" align="left">\n\t\t\t\t\t\t<span><span><span style="font-size:9pt;">\u4e0d\u80fd\u7528\u4e8e\u63a5\u6536\uff0c\u53ea\u7528\u4e8e\u53d1\u9001\uff08\u9700\u8981\u6784\u9020IP\u9996\u90e8\uff09<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n<\/tr>\n<tr>\n<td valign="top" width="132">\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t\t<span><span><span style="font-size:9pt;">OSPF<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n<td valign="top" width="132">\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t\t<span><span><span style="font-size:9pt;">89<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n<td valign="top" width="355">\n<p style="text-align:left;" class="MsoNormal" align="left">\n\t\t\t\t\t\t<span><span><span style="font-size:9pt;">\u63a5\u6536\u534f\u8bae\u53f7\u4e3a89\u7684\u62a5\u6587<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n<\/tr>\n<tr>\n<td valign="top" width="132">\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t\t<span><span><span style="font-size:9pt;">\u2026\u2026 <\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n<td valign="top" width="132">\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t\t\t\t\t\t<span><span><span style="font-size:9pt;">\u2026\u2026 <\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n<td valign="top" width="355">\n<p style="text-align:left;" class="MsoNormal" align="left">\n\t\t\t\t\t\t<span><span><span style="font-size:9pt;">\u2026\u2026<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span style="font-family:\u5b8b\u4f53;">\u8868<\/span><span>2<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e2d<\/span><span>protocol<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u53d6\u503c\u4e3a<\/span><span>IPPROTO_RAW<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u662f\u6bd4\u8f83\u7279\u6b8a\u7684\uff0c\u8868\u793a\u5957\u63a5\u5b57\u4e0d\u80fd\u7528\u4e8e\u63a5\u6536\uff0c\u53ea\u80fd\u7528\u4e8e\u53d1\u9001\uff08\u4e14\u53d1\u9001\u65f6\u9700\u8981\u4ece<\/span><span>IP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u9996\u90e8\u5f00\u59cb\u6784\u9020\u62a5\u6587\uff09\u3002\u5177\u4f53\u7684\u5b9e\u73b0\u7ec6\u8282\u5728<\/span><span>2.3<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u8282\u4e2d\u4f1a\u8be6\u7ec6\u4ecb\u7ecd\u3002<\/span><\/span><\/span>\n<\/p>\n<p class="MsoNormal">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p>\n\t \n<\/p>\n<p><span><span><span style="line-height:240%;font-family:\u5b8b\u4f53;font-size:14pt;">\u4e8c\u3001\u539f\u59cb\u5957\u63a5\u5b57\u5b9e\u73b0<\/span><\/span><\/span><span><span><span style="line-height:240%;font-size:14pt;"> <\/span><\/span><\/span> <\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span style="font-family:\u5b8b\u4f53;">\u672c\u8282\u4e3b\u8981\u9996\u5148\u4ecb\u7ecd\u94fe\u8def\u5c42\u548c\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u62a5\u6587\u7684\u6536\u53d1\u603b\u4f53\u6d41\u7a0b\uff0c\u518d\u5206\u522b\u5bf9\u4e24\u7c7b\u5957\u63a5\u5b57\u7684\u521b\u5efa\u3001\u63a5\u6536\u3001\u53d1\u9001\u7b49\u5177\u4f53\u5b9e\u73b0\u7ec6\u8282\u8fdb\u884c\u4ecb\u7ecd\u3002<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p>\n\t \n<\/p>\n<p><span><span><span style="line-height:173%;font-size:12pt;">2.1<span>  <\/span><\/span><\/span><\/span><span><span><span style="line-height:173%;font-family:\u5b8b\u4f53;font-size:12pt;">\u539f\u59cb\u5957\u63a5\u5b57\u62a5\u6587\u6536\u53d1\u6d41\u7a0b<\/span><\/span><\/span><span><span><span style="line-height:173%;font-size:12pt;"> <\/span><\/span><\/span> <\/p>\n<p style="text-align:center;text-indent:-7.05pt;margin-left:0cm;" class="MsoNormal" align="center">\n\t<span><span><span><\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;font-size:9pt;"><a href="http:\/\/blog.chinaunix.net\/attachment\/201210\/27\/27074062_13513446869lGZ.jpg" target="_blank"><img title="1" alt="1" src="http:\/\/blog.chinaunix.net\/attachment\/201210\/27\/27074062_1351344687GMZT.jpg" border="0" height="364" width="689" \/><\/a> <\/span><\/span><\/span>\n<\/p>\n<p style="text-align:center;text-indent:-7.05pt;margin-left:0cm;" class="MsoNormal" align="center">\n\t<span><span><span style="font-family:\u5b8b\u4f53;font-size:9pt;">\u56fe<\/span><\/span><\/span><span><span><span style="font-size:9pt;">1<span>  <\/span><\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;font-size:9pt;">\u539f\u59cb\u5957\u63a5\u5b57\u6536\u53d1\u6d41\u7a0b<\/span><\/span><\/span>\n<\/p>\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p>\n\t \n<\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span style="font-family:\u5b8b\u4f53;">\u5982\u4e0a\u56fe<\/span><span>1<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6240\u793a\u4e3a\u94fe\u8def\u5c42\u548c\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u7684\u6536\u53d1\u603b\u4f53\u6d41\u7a0b\u3002\u7f51\u5361\u9a71\u52a8\u6536\u5230\u62a5\u6587\u540e\u5728\u8f6f\u4e2d\u65ad\u4e0a\u4e0b\u6587\u4e2d\u7531<\/span><span>netif_receive_skb()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u5904\u7406\uff0c\u5339\u914d\u662f\u5426\u6709\u6ce8\u518c\u7684\u94fe\u8def\u5c42\u539f\u59cb\u5957\u63a5\u5b57\uff0c\u82e5\u5339\u914d\u4e0a\u5c31\u901a\u8fc7<\/span><span>skb_clone()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6765\u514b\u9686\u62a5\u6587\uff0c\u5e76\u5c06\u62a5\u6587\u4ea4\u7ed9\u76f8\u5e94\u7684\u539f\u59cb\u5957\u63a5\u5b57\u3002\u5bf9\u4e8e<\/span><span>IP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u62a5\u6587\uff0c\u5728\u534f\u8bae\u6808\u7684<\/span><span>ip_local_deliver_finish()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u51fd\u6570\u4e2d\u4f1a\u5339\u914d\u662f\u5426\u6709\u6ce8\u518c\u7684\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\uff0c\u82e5\u5339\u914d\u4e0a\u5c31\u901a\u8fc7<\/span><span>skb_clone()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u514b\u9686\u62a5\u6587\u5e76\u4ea4\u7ed9\u76f8\u5e94\u7684\u539f\u59cb\u5957\u63a5\u5b57\u6765\u5904\u7406\u3002<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span style="font-family:\u5b8b\u4f53;font-size:9pt;">\u6ce8\u610f\uff1a\u8fd9\u91cc\u53ea\u662f\u5c06\u62a5\u6587\u514b\u9686\u4e00\u4efd\u4ea4\u7ed9\u539f\u59cb\u5957\u63a5\u5b57\uff0c\u800c\u8be5\u62a5\u6587\u8fd8\u662f\u4f1a\u7ee7\u7eed\u8d70\u540e\u7eed\u7684\u534f\u8bae\u6808\u5904\u7406\u6d41\u7a0b\u3002<\/span><\/span><\/span><span><span><span style="font-size:9pt;"> <\/span><\/span><\/span>\n<\/p>\n<p class="MsoNormal">\n\t<span><span><span><span>      <\/span><\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u94fe\u8def\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u7684\u53d1\u9001\uff0c\u76f4\u63a5\u7531\u5957\u63a5\u5b57\u5c42\u8c03\u7528<\/span><span>packet_sendmsg()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u51fd\u6570\uff0c\u6700\u7ec8\u518d\u8c03\u7528\u7f51\u5361\u9a71\u52a8\u7684\u53d1\u9001\u51fd\u6570\u3002\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u7684\u53d1\u9001\u5b9e\u73b0\u8981\u76f8\u5bf9\u590d\u6742\u4e00\u4e9b\uff0c\u7531\u5957\u63a5\u5b57\u5c42\u8c03\u7528<\/span><span>inet_sendmsg()->raw_sendmsg()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\uff0c\u518d\u7ecf\u8fc7\u8def\u7531\u548c\u90bb\u5c45\u5b50\u7cfb\u7edf\u7684\u5904\u7406\u540e\uff0c\u6700\u7ec8\u8c03\u7528\u7f51\u5361\u9a71\u52a8\u7684\u53d1\u9001\u51fd\u6570\u3002\u82e5\u6ce8\u518c\u4e86<\/span><span>ETH_P_ALL<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7c7b\u578b\u5957\u63a5\u5b57\uff0c\u8fd8\u9700\u8981\u5c06\u5916\u53d1\u62a5\u6587\u518d\u6536\u56de\u53bb\u3002<\/span><\/span><\/span>\n<\/p>\n<p class="MsoNormal">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p>\n\t \n<\/p>\n<p><span><span><span style="line-height:173%;font-size:12pt;">2.2<span>  <\/span><\/span><\/span><\/span><span><span><span style="line-height:173%;font-family:\u5b8b\u4f53;font-size:12pt;">\u94fe\u8def\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u7684\u5b9e\u73b0<\/span><\/span><\/span><span><span><span style="line-height:173%;font-size:12pt;"> <\/span><\/span><\/span><span><span><span style="line-height:173%;font-size:10.5pt;">2.2.1<span>  <\/span><\/span><\/span><\/span><span><span><span style="line-height:173%;font-family:\u5b8b\u4f53;font-size:10.5pt;">\u5957\u63a5\u5b57\u521b\u5efa<\/span><\/span><\/span><span><span><span style="line-height:173%;font-size:10.5pt;"> <\/span><\/span><\/span> <\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><a name="OLE_LINK16"><\/a><a name="OLE_LINK15"><\/a><span><span><span style="font-family:\u5b8b\u4f53;">\u8c03\u7528<\/span><span>socket()<\/span><\/span><\/span><\/span><\/span><span><span><span><span><span style="font-family:\u5b8b\u4f53;">\u51fd\u6570\u521b\u5efa\u5957\u63a5\u5b57\u7684\u6d41\u7a0b\u5982\u4e0b\uff0c\u94fe\u8def\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u6700\u7ec8\u7531<\/span><span>packet_create()<\/span><\/span><\/span><\/span><\/span><span><span><span><span><span style="font-family:\u5b8b\u4f53;">\u521b\u5efa<\/span><\/span><\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u3002<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span>sys_socket()->sock_create()->__sock_create()->packet_create()<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p>\n\t<span><span><span style="font-family:\u5b8b\u4f53;">    \u5f53<\/span><span>socket()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u51fd\u6570\u7684\u7b2c\u4e09\u4e2a\u53c2\u6570<\/span><span>protocol<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e3a\u975e\u96f6\u7684\u60c5\u51b5\u4e0b\uff0c\u4f1a\u8c03\u7528<\/span><span>dev_add_pack()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u5c06\u94fe\u8def\u5c42\u5957\u63a5\u5b57<\/span><span>packet_sock<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7684<\/span><span>packet_type<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7ed3\u6784\u94fe\u5230<\/span><span>ptype_all<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u94fe\u8868\u6216<\/span><span>ptype_base<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u94fe\u8868\u4e2d\u3002<\/span><\/span><\/span><span><span><span><span>    <\/span><\/span><\/span><\/span>\n<\/p>\n<div>\n<div id="code406" class="codeText">\n<ol class="dp-css">\n<li>\n\t\t\t\t<span style="color:#000000;">void dev_add_pack<span style="color:#0000cc;">(<\/span>struct packet_type <span style="color:#0000cc;">*<\/span>pt<span style="color:#0000cc;">)<\/span> <br \/>\n<\/span>\n\t\t\t<\/li>\n<li>\n\t\t\t\t<span style="color:#0000cc;">{<\/span> \n\t\t\t<\/li>\n<li>\n\t\t\t\t        \u2026\u2026 \n\t\t\t<\/li>\n<li>\n\t\t\t\t        <span style="color:#0000ff;">if<\/span> <span style="color:#0000cc;">(<\/span>pt<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span>type <span style="color:#0000cc;">=<\/span><span style="color:#0000cc;">=<\/span> htons<span style="color:#0000cc;">(<\/span>ETH_P_ALL<span style="color:#0000cc;">)<\/span><span style="color:#0000cc;">)<\/span> <span style="color:#0000cc;">{<\/span> \n\t\t\t<\/li>\n<li>\n\t\t\t\t                netdev_nit<span style="color:#0000cc;">+<\/span><span style="color:#0000cc;">+<\/span><span style="color:#0000cc;">;<\/span> \n\t\t\t<\/li>\n<li>\n\t\t\t\t                list_add_rcu<span style="color:#0000cc;">(<\/span><span style="color:#0000cc;">&<\/span>pt<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span>list<span style="color:#0000cc;">,<\/span> <span style="color:#0000cc;">&<\/span>ptype_all<span style="color:#0000cc;">)<\/span><span style="color:#0000cc;">;<\/span> \n\t\t\t<\/li>\n<li>\n\t\t\t\t        <span style="color:#0000cc;">}<\/span> <span style="color:#0000ff;">else<\/span> <span style="color:#0000cc;">{<\/span> \n\t\t\t<\/li>\n<li>\n\t\t\t\t                hash <span style="color:#0000cc;">=<\/span> ntohs<span style="color:#0000cc;">(<\/span>pt<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span>type<span style="color:#0000cc;">)<\/span> <span style="color:#0000cc;">&<\/span> 15<span style="color:#0000cc;">;<\/span> \n\t\t\t<\/li>\n<li>\n\t\t\t\t                list_add_rcu<span style="color:#0000cc;">(<\/span><span style="color:#0000cc;">&<\/span>pt<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span>list<span style="color:#0000cc;">,<\/span> <span style="color:#0000cc;">&<\/span>ptype_base<span style="color:#0000cc;">[<\/span>hash<span style="color:#0000cc;">]<\/span><span style="color:#0000cc;">)<\/span><span style="color:#0000cc;">;<\/span> \n\t\t\t<\/li>\n<li>\n\t\t\t\t        <span style="color:#0000cc;">}<\/span> \n\t\t\t<\/li>\n<li>\n\t\t\t\t        \u2026\u2026 \n\t\t\t<\/li>\n<li>\n\t\t\t\t<span style="color:#0000cc;">}<\/span>\n\t\t\t<\/li>\n<\/ol><\/div>\n<\/div>\n<p class="MsoNormal">\n\t<span><span><span style="font-family:\u5b8b\u4f53;">    \u5f53<\/span><span>protocol<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e3a<\/span><span>ETH_P_ALL<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u65f6\uff0c\u4f1a\u5c06\u5957\u63a5\u5b57\u52a0\u5165\u5230<\/span><span>ptype_all<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u94fe\u8868\u4e2d\u3002\u5982\u56fe<\/span><span>2<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6240\u793a\uff0c\u8fd9\u91cc\u521b\u5efa\u4e86\u4e24\u4e2a\u94fe\u8def\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u3002<\/span><\/span><\/span>\n<\/p>\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t<span><span><span style="font-family:\u5b8b\u4f53;font-size:9pt;"><a href="http:\/\/blog.chinaunix.net\/attachment\/201210\/27\/27074062_1351344688czDk.jpg" target="_blank"><img title="2" alt="2" src="http:\/\/blog.chinaunix.net\/attachment\/201210\/27\/27074062_1351344689gYnu.jpg" border="0" height="125" width="399" \/><\/a> <\/span><\/span><\/span>\n<\/p>\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t<span><span><span style="font-family:\u5b8b\u4f53;font-size:9pt;">\u56fe<\/span><\/span><\/span><span><span><span style="font-size:9pt;">2 <span> <\/span>ptype_all<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;font-size:9pt;">\u94fe\u8868<\/span><\/span><\/span><span><span><span style="font-size:9pt;"> <\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span style="font-family:\u5b8b\u4f53;">\u5f53<\/span><span>protocol<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e3a\u5176\u5b83\u975e<\/span><span>0<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u503c\u65f6\uff0c\u4f1a\u5c06\u5957\u63a5\u5b57\u52a0\u5165\u5230<\/span><span>ptype_base<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u94fe\u8868\u4e2d\u3002\u5982\u56fe<\/span><span>3<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6240\u793a\uff0c\u534f\u8bae\u6808\u672c\u8eab\u4e5f\u9700\u8981\u6ce8\u518c<\/span><span>packet_type<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7ed3\u6784\uff0c\u56fe\u4e2d\u6d45\u8272\u7684\u4e24\u4e2a<\/span><span>packet_type<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7ed3\u6784\u5206\u522b\u662f<\/span><span>IP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u534f\u8bae\u548c<\/span><span>ARP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u534f\u8bae\u6ce8\u518c\u7684\uff0c\u5176\u5904\u7406\u51fd\u6570\u5206\u522b\u4e3a<\/span><span>ip_rcv()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u548c<\/span><span>arp_rcv()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u3002\u56fe\u4e2d\u53e6\u5916<\/span><span>3<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e2a\u6df1\u8272\u7684<\/span><span>packet_type<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7ed3\u6784\u5219\u662f\u94fe\u8def\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u6ce8\u518c\u7684\uff0c\u5206\u522b\u7528\u4e8e\u63a5\u6536\u7c7b\u578b\u4e3a<\/span><span>ETH_P_IP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u3001<\/span><span>ETH_P_ARP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u548c<\/span><span>0x0810<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7c7b\u578b\u7684\u62a5\u6587\u3002<\/span><\/span><\/span>\n<\/p>\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t<span><span><span style="font-family:\u5b8b\u4f53;font-size:9pt;"><a href="http:\/\/blog.chinaunix.net\/attachment\/201210\/27\/27074062_1351344689BIO9.jpg" target="_blank"><img title="3" alt="3" src="http:\/\/blog.chinaunix.net\/attachment\/201210\/27\/27074062_1351344690Mw0Q.jpg" border="0" height="187" width="478" \/><\/a> <\/span><\/span><\/span>\n<\/p>\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t<span><span><span style="font-family:\u5b8b\u4f53;font-size:9pt;">\u56fe<\/span><\/span><\/span><span><span><span style="font-size:9pt;">3<span>  <\/span>ptype_base<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;font-size:9pt;">\u94fe\u8868<\/span><\/span><\/span><span><span><span style="font-size:9pt;"> <\/span><\/span><\/span>\n<\/p>\n<p class="MsoNormal">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p>\n\t \n<\/p>\n<p><span><span><span style="line-height:173%;font-size:10.5pt;">2.2.2<span>  <\/span><\/span><\/span><\/span><span><span><span style="line-height:173%;font-family:\u5b8b\u4f53;font-size:10.5pt;">\u62a5\u6587\u63a5\u6536<\/span><\/span><\/span><span><span><span style="line-height:173%;font-size:10.5pt;"> <\/span><\/span><\/span> <\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span style="font-family:\u5b8b\u4f53;">\u7f51\u5361\u9a71\u52a8\u7a0b\u5e8f\u63a5\u6536\u5230\u62a5\u6587\u540e\uff0c\u5728\u8f6f\u4e2d\u65ad\u4e0a\u4e0b\u6587\u7531<\/span><span>netif_receive_skb()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u5904\u7406\u3002\u9996\u5148\u4f1a\u9010\u4e2a\u904d\u5386<\/span><span>ptype_all<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u94fe\u8868\u4e2d\u7684<\/span><span>packet_type<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7ed3\u6784\uff0c\u82e5\u6ee1\u8db3\u6761\u4ef6\u201c<\/span><span>(!ptype->dev || ptype->dev == skb->dev)<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u201d\uff0c\u5373\u5957\u63a5\u5b57\u672a\u7ed1\u5b9a\u6216\u8005\u5957\u63a5\u5b57\u7ed1\u5b9a\u7f51\u53e3\u4e0e<\/span><span>skb<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6240\u5728\u7f51\u53e3\u5339\u914d\uff0c\u5c31\u589e\u52a0\u62a5\u6587\u5f15\u7528\u8ba1\u6570\u5e76\u4ea4\u7ed9<\/span><span>packet_rcv()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u51fd\u6570\u5904\u7406\uff08\u82e5\u4f7f\u7528<\/span><span>PACKET_MMAP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6536\u5305\u65b9\u5f0f\u5219\u7531<\/span><span>tpacket_rcv()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u51fd\u6570\u5904\u7406\uff09\u3002<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span style="font-family:\u5b8b\u4f53;">\u7f51\u5361\u9a71\u52a8<\/span><span>->netif_receive_skb()->deliver_skb()->packet_rcv()\/tpacket_rcv()<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p>\n\t<span><span><span style="font-family:\u5b8b\u4f53;">    \u4ee5\u975e<\/span><span>PACKET_MMAP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6536\u5305\u65b9\u5f0f\u4e3a\u4f8b\u8fdb\u884c\u8bf4\u660e\uff0c<\/span><span>packet_rcv()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u51fd\u6570\u4e2d\u6bd4\u8f83\u91cd\u8981\u7684\u4ee3\u7801\u7247\u6bb5\u5982\u4e0b\u3002\u5f53\u62a5\u6587<\/span><span>skb<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u5230\u8fbe<\/span><span>packet_rcv()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u51fd\u6570\u65f6\uff0c\u5176<\/span><span>skb->data<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6240\u6307\u7684\u6570\u636e\u662f\u4e0d\u5305\u542b<\/span><span>MAC<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u9996\u90e8\u7684\uff0c\u6240\u4ee5\u5bf9\u4e8e<\/span><span>type<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e3a\u975e<\/span><span>SOCK_DGRAM<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\uff08\u5373<\/span><span>SOCK_RAW<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\uff09\u7c7b\u578b\uff0c\u9700\u8981\u5c06<\/span><span>skb->data<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6307\u9488\u524d\u79fb\uff0c\u4ee5\u4fbf\u6570\u636e\u90e8\u5206\u53ef\u4ee5\u5305\u542b<\/span><span>MAC<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u9996\u90e8\u3002\u6700\u540e\u5c06<\/span><span>skb<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u653e\u5230\u5957\u63a5\u5b57\u7684\u63a5\u6536\u961f\u5217<\/span><span>sk->sk_receive_queue<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e2d\uff0c\u5e76\u5524\u9192\u7528\u6237\u6001\u8fdb\u7a0b\u6765\u8bfb\u53d6\u5957\u63a5\u5b57\u4e2d\u7684\u6570\u636e\u3002<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;"><\/span><\/span><\/span>\n<\/p>\n<div>\n<div id="code78" class="codeText">\n<ol class="dp-css">\n<li>\n\t\t\t\t<span style="color:#000000;">\u2026\u2026 <br \/>\n<\/span>\n\t\t\t<\/li>\n<li>\n\t\t\t\t<span style="color:#0000ff;">if<\/span> <span style="color:#0000cc;">(<\/span>sk<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span>sk_type <span style="color:#0000cc;">!<\/span><span style="color:#0000cc;">=<\/span> SOCK_DGRAM<span style="color:#0000cc;">)<\/span> <span style="color:#0000cc;">\/<\/span><span style="color:#0000cc;">\/<\/span>\u5373SOCK_RAW\u7c7b\u578b \n\t\t\t<\/li>\n<li>\n\t\t\t\t        skb_push<span style="color:#0000cc;">(<\/span>skb<span style="color:#0000cc;">,<\/span> skb<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span>data <span style="color:#0000cc;">–<\/span> skb<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span>mac<span style="color:#0000cc;">.<\/span>raw<span style="color:#0000cc;">)<\/span><span style="color:#0000cc;">;<\/span> \n\t\t\t<\/li>\n<li>\n\t\t\t\t\u2026\u2026 \n\t\t\t<\/li>\n<li>\n\t\t\t\t__skb_queue_tail<span style="color:#0000cc;">(<\/span><span style="color:#0000cc;">&<\/span>sk<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span>sk_receive_queue<span style="color:#0000cc;">,<\/span> skb<span style="color:#0000cc;">)<\/span><span style="color:#0000cc;">;<\/span> \n\t\t\t<\/li>\n<li>\n\t\t\t\tsk<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span>sk_data_ready<span style="color:#0000cc;">(<\/span>sk<span style="color:#0000cc;">,<\/span> skb<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span><span style="color:#ff0000;">len<\/span><span style="color:#0000cc;">)<\/span><span style="color:#0000cc;">;<\/span> <span style="color:#0000cc;">\/<\/span><span style="color:#0000cc;">\/<\/span>\u5524\u9192\u8fdb\u7a0b\u8bfb\u53d6\u6570\u636e \n\t\t\t<\/li>\n<li>\n\t\t\t\t\u2026\u2026\n\t\t\t<\/li>\n<\/ol><\/div>\n<\/div>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span>PACKET_MMAP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6536\u5305\u65b9\u5f0f\u7684\u5b9e\u73b0\u6709\u6240\u4e0d\u540c\uff0c<\/span><span>tpacket_rcv()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u51fd\u6570\u5c06<\/span><span>skb->data<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u62f7\u8d1d\u5230\u4e0e\u7528\u6237\u6001<\/span><span>mmap<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6620\u5c04\u7684\u5171\u4eab\u5185\u5b58\u4e2d\uff0c\u6700\u540e\u5524\u9192\u7528\u6237\u6001\u8fdb\u7a0b\u6765\u8bfb\u53d6\u6570\u636e\u3002\u7531\u4e8e\u62a5\u6587\u7684\u5185\u5bb9\u5df2\u5b58\u653e\u5728\u5185<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6838\u7a7a\u95f4\u548c\u7528\u6237\u7a7a\u95f4\u5171\u4eab\u7684\u7f13\u51b2\u533a\u4e2d\uff0c\u7528\u6237\u6001\u53ef\u4ee5\u76f4\u63a5\u8bfb\u53d6\u4ee5\u51cf\u5c11\u6570\u636e\u7684\u62f7\u8d1d\uff0c\u6240\u4ee5\u8fd9\u79cd\u65b9\u5f0f\u6548\u7387\u6bd4\u8f83\u9ad8\u3002<\/span><\/span><\/span>\n<\/p>\n<p class="MsoNormal">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p>\n\t<span><span><span style="font-family:\u5b8b\u4f53;">    \u4e0a\u9762\u4ecb\u7ecd\u4e86\u62a5\u6587\u63a5\u6536\u5728\u8f6f\u4e2d\u65ad\u7684\u5904\u7406\u6d41\u7a0b\u3002\u4e0b\u9762\u4ee5\u975e<\/span><span>PACKET_MMAP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6536\u5305\u65b9\u5f0f\u4e3a\u4f8b\uff0c\u4ecb\u7ecd\u7528\u6237\u6001\u8bfb\u53d6\u62a5\u6587\u6570\u636e\u7684\u6d41\u7a0b\u3002\u7528\u6237\u6001<\/span><span>recvmsg()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6700\u7ec8\u8c03\u7528<\/span><span>skb_recv_datagram()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\uff0c\u5982\u679c\u5957\u63a5\u5b57\u63a5\u6536\u961f\u5217<\/span><span>sk->sk_receive_queue<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e2d\u6709\u62a5\u6587\u5c31\u53d6<\/span><span>skb<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u5e76\u8fd4\u56de\u3002\u5426\u5219\u8c03\u7528<\/span><span>wait_for_packet()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7b49\u5f85\uff0c\u76f4\u5230\u5185\u6838\u8f6f\u4e2d\u65ad\u6536\u5230\u62a5\u6587\u5e76\u5524\u9192\u7528\u6237\u6001\u8fdb\u7a0b\u3002<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span>sys_recvmsg()->sock_recvmsg()->\u2026->packet_recvmsg()->skb_recv_datagram()<\/span><\/span><\/span>\n<\/p>\n<p class="MsoNormal">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p>\n\t \n<\/p>\n<p><span><span><span style="line-height:173%;font-size:10.5pt;">2.2.3<span>  <\/span><\/span><\/span><\/span><span><span><span style="line-height:173%;font-family:\u5b8b\u4f53;font-size:10.5pt;">\u62a5\u6587\u53d1\u9001<\/span><\/span><\/span><span><span><span style="line-height:173%;font-size:10.5pt;"> <\/span><\/span><\/span> <\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span style="font-family:\u5b8b\u4f53;">\u7528\u6237\u6001\u8c03\u7528<\/span><span>sendto()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6216<\/span><span>sendmsg()<\/span><\/span><\/span><a name="OLE_LINK19"><\/a><span><span><span style="font-family:\u5b8b\u4f53;"><span>\u53d1\u9001\u62a5\u6587\u7684\u5185\u6838\u6001\u5904\u7406\u6d41\u7a0b\u5982\u4e0b<\/span><\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\uff0c\u7531\u5957\u63a5\u5b57\u5c42\u6700\u7ec8\u4f1a\u8c03\u7528\u5230<\/span><span>packet_sendmsg()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u3002<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span>sys_sendto()->sock_sendmsg()->__sock_sendmsg()->packet_sendmsg()->dev_queue_xmit()<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p>\n\t<span><span><span style="font-family:\u5b8b\u4f53;">    \u8be5\u51fd\u6570\u6bd4\u8f83\u91cd\u8981\u7684\u51fd\u6570\u7247\u6bb5\u5982\u4e0b\u3002\u9996\u5148\u8fdb\u884c\u53c2\u6570\u68c0\u67e5\u53ca<\/span><span>skb<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u5206\u914d\uff0c\u518d\u8c03\u7528\u9a71\u52a8\u7a0b\u5e8f\u7684<\/span><span>hard_header<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u51fd\u6570\uff08\u5bf9\u4e8e\u4ee5\u592a\u7f51\u9a71\u52a8\u662f<\/span><span>eth_header()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u51fd\u6570\uff09\u6765\u6784\u9020\u62a5\u6587\u7684<\/span><span>MAC<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u5934\u90e8\uff0c\u6b64\u65f6\u7684<\/span><span>skb->data<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u662f\u6307\u5411<\/span><span>MAC<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u9996\u90e8\u7684\uff0c\u4e14<\/span><span>skb->len<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e3a<\/span><span>MAC<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u9996\u90e8\u957f\u5ea6\uff08\u5373<\/span><span>14<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\uff09\u3002\u5bf9\u4e8e\u521b\u5efa\u65f6\u6307\u5b9a<\/span><span>type<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e3a<\/span><span>SOCK_RAW<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7c7b\u578b\u5957\u63a5\u5b57\uff0c\u7531\u4e8e\u5728\u53d1\u9001\u65f6\u9700\u8981\u81ea\u884c\u6784\u9020<\/span><span>MAC<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u5934\u90e8\uff0c\u6240\u4ee5\u5c06<\/span><span>skb->tail<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6307\u9488\u6062\u590d\u5230<\/span><span>MAC<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u9996\u90e8\u5f00\u59cb\u7684\u4f4d\u7f6e\uff0c\u5e76\u5c06<\/span><span>skb->len<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u8bbe\u7f6e\u4e3a<\/span><span>0<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\uff08\u5373\u4e0d\u4f7f\u7528\u5185\u6838\u6784\u9020\u7684<\/span><span>MAC<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u9996\u90e8\uff09\u3002\u63a5\u7740\u518d\u8c03\u7528<\/span><span>memcpy_fromiovec()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4ece<\/span><span>skb->tail<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7684\u4f4d\u7f6e\u5f00\u59cb\u62f7\u8d1d\u62a5\u6587\u6570\u636e\uff0c\u6700\u7ec8\u8c03\u7528\u7f51\u5361\u9a71\u52a8\u7684\u53d1\u9001\u51fd\u6570\u5c06\u62a5\u6587\u53d1\u9001\u51fa\u53bb\u3002<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:-13.5pt;margin-left:34.5pt;" class="MsoNormal">\n\t<span><span><span style="font-family:\u5b8b\u4f53;font-size:9pt;">\u6ce8\uff1a\u5982\u679c\u521b\u5efa\u5957\u63a5\u5b57\u65f6\u6307\u5b9a<\/span><\/span><\/span><span><span><span style="font-size:9pt;">type<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;font-size:9pt;">\u4e3a<\/span><\/span><\/span><span><span><span style="font-size:9pt;">SOCK_DGRAM<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;font-size:9pt;">\uff0c\u5219\u4f7f\u7528\u5185\u6838\u6784\u9020\u7684<\/span><\/span><\/span><span><span><span style="font-size:9pt;">MAC<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;font-size:9pt;">\u9996\u90e8\uff0c\u7528\u6237\u6001\u53d1\u9001\u7684\u6570\u636e\u4e2d\u4e0d\u542b<\/span><\/span><\/span><span><span><span style="font-size:9pt;">MAC<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;font-size:9pt;">\u5934\u90e8\u6570\u636e\u3002<\/span><\/span><\/span>\n<\/p>\n<p class="MsoNormal">\n\t\n<\/p>\n<table cellpadding="0" cellspacing="0" width="100%">\n<tbody>\n<tr>\n<td>\n<div>\n<p class="MsoNormal">\n\t\t\t\t\t\t<span style="font-size:9pt;"><span>         <br \/>\n<\/span><\/span>\n\t\t\t\t\t<\/p>\n<div>\n<div id="code312" class="codeText">\n<ol class="dp-css">\n<li>\n\t\t\t\t\t\t\t\t\t<span style="color:#000000;">\u2026\u2026 <br \/>\n<\/span>\n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\tres <span style="color:#0000cc;">=<\/span> dev<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span>hard_header<span style="color:#0000cc;">(<\/span>skb<span style="color:#0000cc;">,<\/span> dev<span style="color:#0000cc;">,<\/span> ntohs<span style="color:#0000cc;">(<\/span>proto<span style="color:#0000cc;">)<\/span><span style="color:#0000cc;">,<\/span> addr<span style="color:#0000cc;">,<\/span> <span style="color:#0000ff;">NULL<\/span><span style="color:#0000cc;">,<\/span> <span style="color:#ff0000;">len<\/span><span style="color:#0000cc;">)<\/span><span style="color:#0000cc;">;<\/span> <span style="color:#0000cc;">\/<\/span><span style="color:#0000cc;">\/<\/span>\u6784\u9020MAC\u9996\u90e8 \n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t<span style="color:#0000ff;">if<\/span> <span style="color:#0000cc;">(<\/span>sock<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span>type <span style="color:#0000cc;">!<\/span><span style="color:#0000cc;">=<\/span> SOCK_DGRAM<span style="color:#0000cc;">)<\/span> <span style="color:#0000cc;">{<\/span> \n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t        skb<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span>tail <span style="color:#0000cc;">=<\/span> skb<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span>data<span style="color:#0000cc;">;<\/span> <span style="color:#0000cc;">\/<\/span><span style="color:#0000cc;">\/<\/span>SOCK_RAW\u7c7b\u578b \n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t        skb<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span><span style="color:#ff0000;">len<\/span> <span style="color:#0000cc;">=<\/span> 0<span style="color:#0000cc;">;<\/span> \n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t<span style="color:#0000cc;">}<\/span> \n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t\u2026\u2026\n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t<span style="color:#ff0000;">err<\/span> <span style="color:#0000cc;">=<\/span> memcpy_fromiovec<span style="color:#0000cc;">(<\/span>skb_put<span style="color:#0000cc;">(<\/span>skb<span style="color:#0000cc;">,<\/span><span style="color:#ff0000;">len<\/span><span style="color:#0000cc;">)<\/span><span style="color:#0000cc;">,<\/span> msg<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span>msg_iov<span style="color:#0000cc;">,<\/span> <span style="color:#ff0000;">len<\/span><span style="color:#0000cc;">)<\/span><span style="color:#0000cc;">;<\/span> <span style="color:#0000cc;">\/<\/span><span style="color:#0000cc;">\/<\/span>\u62f7\u8d1d\u62a5\u6587\u6570\u636e\n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t\u2026\u2026 \n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t<span style="color:#ff0000;">err<\/span> <span style="color:#0000cc;">=<\/span> dev_queue_xmit<span style="color:#0000cc;">(<\/span>skb<span style="color:#0000cc;">)<\/span><span style="color:#0000cc;">;<\/span> <span style="color:#0000cc;">\/<\/span><span style="color:#0000cc;">\/<\/span>\u53d1\u9001\u62a5\u6587 \n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t\u2026\u2026\n\t\t\t\t\t\t\t\t<\/li>\n<\/ol><\/div>\n<\/p><\/div>\n<p class="MsoNormal">\n\t\t\t\t\t\t \n\t\t\t\t\t<\/p>\n<\/p><\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p class="MsoNormal">\n\t<span><span><span style="line-height:173%;font-size:10.5pt;">2.2.4<span>  <\/span><\/span><\/span><\/span><span><span><span style="line-height:173%;font-family:\u5b8b\u4f53;font-size:10.5pt;">\u5176\u5b83<\/span><\/span><\/span><span><span><span style="line-height:173%;font-size:10.5pt;"> <\/span> <\/span><\/span>\n<\/p>\n<p style="text-indent:-21pt;margin-left:21pt;" class="MsoListParagraph">\n\t<span><span><span><span>a)<span style="line-height:normal;font-style:normal;font-size:7pt;font-weight:normal;">         <\/span><\/span><\/span><span style="font-family:\u5b8b\u4f53;">\u5957\u63a5\u5b57\u7684\u7ed1\u5b9a<\/span><\/span><\/span>\n<\/p>\n<p style="margin-left:21pt;" class="MsoNormal">\n\t<span><span><span style="font-family:\u5b8b\u4f53;">\u94fe\u8def\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u53ef\u8c03\u7528<\/span><span>bind()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u51fd\u6570\u8fdb\u884c\u7ed1\u5b9a\uff0c\u8ba9<\/span><span>packet_type<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7ed3\u6784<\/span><span>dev<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u5b57\u6bb5\u6307\u5411\u76f8\u5e94\u7684<\/span><span>net_device<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7ed3\u6784\uff0c\u5373\u5c06\u5957\u63a5\u5b57\u7ed1\u5b9a\u5230\u76f8\u5e94\u7684\u7f51\u53e3\u4e0a\u3002\u5982<\/span><span>2.2.2<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u8282\u62a5\u6587\u63a5\u6536\u7684\u63cf\u8ff0\uff0c\u5728\u63a5\u6536\u65f6\u5982\u679c\u5957\u63a5\u53e3\u6709\u7ed1\u5b9a\u5c31\u9700\u8981\u8fdb\u4e00\u6b65\u786e\u8ba4\u5f53\u524d<\/span><span>skb->dev<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u662f\u5426\u4e0e\u7ed1\u5b9a\u7f51\u53e3\u76f8\u5339\u914d\uff0c\u53ea\u6709\u5339\u914d\u7684\u624d\u4f1a\u5c06\u62a5\u6587\u4e0a\u9001\u5230\u76f8\u5e94\u7684\u5957\u63a5\u5b57\u3002<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span>sys_bind()->packet_bind()->packet_do_bind()<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:-21pt;margin-left:21pt;" class="MsoListParagraph">\n\t<span><span><span><span>b)<span style="line-height:normal;font-style:normal;font-size:7pt;font-weight:normal;">        <\/span><\/span><\/span><span style="font-family:\u5b8b\u4f53;">\u5957\u63a5\u5b57\u9009\u9879<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span style="font-family:\u5b8b\u4f53;">\u4ee5\u4e0b\u662f\u6bd4\u8f83\u5e38\u7528\u7684\u5957\u63a5\u5b57\u9009\u9879<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span>PACKET_RX_RING<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\uff1a\u7528\u4e8e<\/span><span>PACKET_MMAP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6536\u5305\u65b9\u5f0f\u8bbe\u7f6e\u63a5\u6536\u73af\u5f62\u961f\u5217<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><a name="OLE_LINK21"><\/a><span><span>PACKET_STATISTICS<\/span><\/span><\/span><\/span><span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\uff1a\u7528\u4e8e\u8bfb\u53d6\u6536\u5305\u7edf\u8ba1\u4fe1\u606f<\/span><\/span><\/span>\n<\/p>\n<p class="MsoNormal">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p>\n\t<span><span><span><span>c)<span style="line-height:normal;font-style:normal;font-size:7pt;font-weight:normal;">       <\/span><\/span><\/span><span style="font-family:\u5b8b\u4f53;">\u4fe1\u606f\u67e5\u770b<\/span><\/span><\/span>\n<\/p>\n<p style="margin-left:18pt;" class="MsoNormal">\n\t<span><span><span style="font-family:\u5b8b\u4f53;">\u94fe\u8def\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u7684\u4fe1\u606f\u53ef\u901a\u8fc7<\/span><\/span><\/span><span><span><span>\/proc\/net\/packet<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u8fdb\u884c\u67e5\u770b\u3002\u5982\u4e0b\u4e3a\u56fe<\/span><\/span><\/span><span><span><span>2<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u548c\u56fe<\/span><\/span><\/span><span><span><span>3<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e2d\u521b\u5efa\u7684\u539f\u59cb\u5957\u63a5\u5b57\u7684\u4fe1\u606f\uff0c\u53ef\u4ee5\u67e5\u770b\u5230\u521b\u5efa\u65f6\u6307\u5b9a\u7684\u534f\u8bae\u7c7b\u578b\u3001\u662f\u5426\u7ed1\u5b9a\u7f51\u53e3\u3001\u5df2\u4f7f\u7528\u7684\u63a5\u6536\u7f13\u5b58\u5927\u5c0f\u7b49\u4fe1\u606f\u3002\u8fd9\u4e9b\u4fe1\u606f\u5bf9\u4e8e\u5206\u6790\u548c\u5b9a\u4f4d\u95ee\u9898\u6709\u5e2e\u52a9\u3002<\/span><\/span><\/span><span><span><span> <\/span><\/span><\/span>\n<\/p>\n<div align="center">\n<div id="code46" class="codeText">\n<div align="left">\n<ol class="dp-css">\n<li>\n\t\t\t\t\tcat \/proc\/net\/packet\n\t\t\t\t<\/li>\n<li>\n\t\t\t\t\tsk RefCnt Type Proto Iface R Rmem User Inode\n\t\t\t\t<\/li>\n<li>\n\t\t\t\t\tffff810007df8400 3 3 0810 0 1 0 0 1310\n\t\t\t\t<\/li>\n<li>\n\t\t\t\t\tffff810007df8800 3 3 0806 0 1 0 0 1309\n\t\t\t\t<\/li>\n<li>\n\t\t\t\t\tffff810007df8c00 3 3 0800 0 1 560 0 1308\n\t\t\t\t<\/li>\n<li>\n\t\t\t\t\tffff810007df8000 3 3 0003 0 1 560 0 1307\n\t\t\t\t<\/li>\n<li>\n\t\t\t\t\tffff810007df3800 3 3 0003 0 1 560 0 1306\n\t\t\t\t<\/li>\n<\/ol><\/div>\n<\/p><\/div>\n<\/div>\n<p style="margin-left:18pt;" class="MsoNormal">\n\t \n<\/p>\n<p><span><span><span style="line-height:173%;font-size:12pt;">2.3<span>  <\/span><\/span><\/span><\/span><span><span><span style="line-height:173%;font-family:\u5b8b\u4f53;font-size:12pt;">\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u7684\u5b9e\u73b0<\/span><\/span><\/span><span><span><span style="line-height:173%;font-size:12pt;"> <\/span><\/span><\/span><span><span><span style="line-height:173%;font-size:10.5pt;">2.3.1<span>  <\/span><\/span><\/span><\/span><span><span><span style="line-height:173%;font-family:\u5b8b\u4f53;font-size:10.5pt;">\u5957\u63a5\u5b57\u521b\u5efa<\/span><\/span><\/span><span><span><span style="line-height:173%;font-size:10.5pt;"> <\/span><\/span><\/span> <\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span style="font-family:\u5b8b\u4f53;">\u5982\u56fe<\/span><span>4<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6240\u793a\uff0c\u5728<\/span><span>IPV4<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u534f\u8bae\u6808\u4e2d\u4e00\u4e2a\u4f20\u8f93\u5c42\u534f\u8bae\uff08\u5982<\/span><span>TCP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\uff0c<\/span><span>UDP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\uff0c<\/span><span>UDP-Lite<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7b49\uff09\u5bf9\u5e94\u4e00\u4e2a<\/span><span>inet_protosw<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7ed3\u6784\uff0c\u800c<\/span><span>inet_protosw<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7ed3\u6784\u4e2d\u53c8\u5305\u542b\u4e86<\/span><span>proto_ops<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7ed3\u6784\u548c<\/span><span>proto<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7ed3\u6784\u3002\u7f51\u7edc\u5b50\u7cfb\u7edf\u521d\u59cb\u5316\u65f6\u5c06\u6240\u6709\u7684<\/span><span>inet_protosw<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7ed3\u6784<\/span><span>hash<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u5230\u5168\u5c40\u7684<\/span><span>inetsw[]<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6570\u7ec4\u4e2d\u3002<\/span><span>proto_ops<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7ed3\u6784\u5b9e\u73b0\u7684\u662f\u4ece\u4e0e\u534f\u8bae\u65e0\u5173\u7684\u5957\u63a5\u53e3\u5c42\u5230\u534f\u8bae\u76f8\u5173\u7684\u4f20\u8f93\u5c42\u7684\u8f6c\u63a5\uff0c\u800c<\/span><span>proto<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7ed3\u6784\u53c8\u5c06\u4f20\u8f93\u5c42\u6620\u5c04\u5230\u7f51\u7edc\u5c42\u3002<\/span><\/span><\/span>\n<\/p>\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p style="text-align:center;text-indent:21pt;" class="MsoNormal" align="center">\n\t<span><span><span style="font-family:\u5b8b\u4f53;font-size:9pt;"><a href="http:\/\/blog.chinaunix.net\/attachment\/201210\/27\/27074062_13513446926Zf4.jpg" target="_blank"><img title="4" alt="4" src="http:\/\/blog.chinaunix.net\/attachment\/201210\/27\/27074062_1351344696L6C6.jpg" border="0" height="335" width="510" \/><\/a> <\/span><\/span><\/span>\n<\/p>\n<p style="text-align:center;text-indent:21pt;" class="MsoNormal" align="center">\n\t<span><span><span style="font-family:\u5b8b\u4f53;font-size:9pt;">\u56fe<\/span><\/span><\/span><span><span><span style="font-size:9pt;">4<span>  <\/span>inetsw[]<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;font-size:9pt;">\u6570\u7ec4\u7ed3\u6784<\/span><\/span><\/span><span><span><span style="font-size:9pt;"> <\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p>\n\t<span><span><span style="font-family:\u5b8b\u4f53;">    \u8c03\u7528<\/span><span>socket()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u51fd\u6570\u521b\u5efa\u5957\u63a5\u5b57\u7684\u6d41\u7a0b\u5982\u4e0b\uff0c\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u6700\u7ec8\u7531<\/span><span>inet_create()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u521b\u5efa\u3002<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span>sys_socket()->sock_create()->__sock_create()->inet_create()<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p>\n\t<span><span><span>    inet_create()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u51fd\u6570\u9664\u7528\u4e8e\u521b\u5efa\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u5916\uff0c\u8fd8\u7528\u4e8e\u521b\u5efa<\/span><span>TCP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u3001<\/span><span>UDP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u5957\u63a5\u5b57\u3002\u9996\u5148\u6839\u636e<\/span><span>socket()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u51fd\u6570\u7684\u7b2c\u4e8c\u4e2a\u53c2\u6570\uff08\u5373<\/span><span>SOCK_RAW<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\uff09\u5728<\/span><span>inetsw[]<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6570\u7ec4\u4e2d\u5339\u914d\u5230\u76f8\u5e94\u7684<\/span><span>inet_protosw<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7ed3\u6784\u3002\u5e76\u5c06\u5957\u63a5\u5b57\u7ed3\u6784\u7684<\/span><span>ops<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u8bbe\u7f6e\u4e3a<\/span><span>inet_sockraw_ops<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\uff0c\u5c06\u5957\u63a5\u5b57\u7ed3\u6784\u7684<\/span><span>sk_prot<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u8bbe\u7f6e\u4e3a<\/span><span>raw_prot<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u3002\u7136\u540e\u5bf9\u4e8e<\/span><span>SOCK_RAW<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7c7b\u578b\u5957\u63a5\u5b57\uff0c\u8fd8\u8981\u5c06<\/span><span>inet->num<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u8bbe\u7f6e\u4e3a\u534f\u8bae\u7c7b\u578b\uff0c\u4ee5\u4fbf\u6700\u540e\u80fd\u8c03\u7528<\/span><span>proto<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7ed3\u6784\u7684<\/span><span>hash<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u51fd\u6570\uff08\u5373<\/span><span>raw_v4_hash()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\uff09\u3002<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t\n<\/p>\n<table cellpadding="0" cellspacing="0" width="100%">\n<tbody>\n<tr>\n<td>\n<div>\n<p class="MsoNormal">\n\t\t\t\t\t\t<span style="font-size:9pt;"><span>         <br \/>\n<\/span><\/span>\n\t\t\t\t\t<\/p>\n<div>\n<div id="code218" class="codeText">\n<ol class="dp-css">\n<li>\n\t\t\t\t\t\t\t\t\t<span style="color:#000000;">\u2026\u2026 <br \/>\n<\/span>\n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\tsock<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span>ops <span style="color:#0000cc;">=<\/span> answer<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span>ops<span style="color:#0000cc;">;<\/span> <span style="color:#0000cc;">\/<\/span><span style="color:#0000cc;">\/<\/span>\u5c06socket\u7ed3\u6784\u7684ops\u8bbe\u7f6e\u4e3ainet_sockraw_ops \n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\tanswer_prot <span style="color:#0000cc;">=<\/span> answer<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span>prot<span style="color:#0000cc;">;<\/span> \n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t\u2026\u2026 \n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t<span style="color:#0000ff;">if<\/span> <span style="color:#0000cc;">(<\/span>SOCK_RAW <span style="color:#0000cc;">=<\/span><span style="color:#0000cc;">=<\/span> sock<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span>type<span style="color:#0000cc;">)<\/span> <span style="color:#0000cc;">{<\/span> <span style="color:#0000cc;">\/<\/span><span style="color:#0000cc;">\/<\/span>SOCK_RAW\u7c7b\u578b\u7684\u5957\u63a5\u5b57\uff0c\u8bbe\u7f6einet<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span>num \n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t        inet<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span>num <span style="color:#0000cc;">=<\/span> protocol<span style="color:#0000cc;">;<\/span> \n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t        <span style="color:#0000ff;">if<\/span> <span style="color:#0000cc;">(<\/span>IPPROTO_RAW <span style="color:#0000cc;">=<\/span><span style="color:#0000cc;">=<\/span> protocol<span style="color:#0000cc;">)<\/span> <span style="color:#0000cc;">\/<\/span><span style="color:#0000cc;">\/<\/span>protocol\u4e3aIPPROTO_RAW\u7684\u7279\u6b8a\u5904\u7406\uff0c \n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t                inet<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span>hdrincl <span style="color:#0000cc;">=<\/span> 1<span style="color:#0000cc;">;<\/span> \u540e\u7eed\u5728\u62a5\u6587\u53d1\u9001\u65f6\u4f1a\u518d\u8bb2\u5230 \n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t<span style="color:#0000cc;">}<\/span> \n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t\u2026\u2026\n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t<span style="color:#0000ff;">if<\/span> <span style="color:#0000cc;">(<\/span>inet<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span>num<span style="color:#0000cc;">)<\/span> <span style="color:#0000cc;">{<\/span>\n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t<span style="color:#0000cc;">        <\/span>inet<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span>sport <span style="color:#0000cc;">=<\/span> htons<span style="color:#0000cc;">(<\/span>inet<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span>num<span style="color:#0000cc;">)<\/span><span style="color:#0000cc;">;<\/span> \n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t        sk<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span>sk_prot<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span>hash<span style="color:#0000cc;">(<\/span>sk<span style="color:#0000cc;">)<\/span><span style="color:#0000cc;">;<\/span> <span style="color:#0000cc;">\/<\/span><span style="color:#0000cc;">\/<\/span>\u8c03\u7528raw_v4_hash<span style="color:#0000cc;">(<\/span><span style="color:#0000cc;">)<\/span>\u51fd\u6570\u5c06\u5957\u63a5\u5b57\u94fe\u5230raw_v4_htable\u4e2d \n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t<span style="color:#0000cc;">}<\/span> \n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t\u2026\u2026\n\t\t\t\t\t\t\t\t<\/li>\n<\/ol><\/div>\n<\/p><\/div>\n<p class="MsoNormal">\n\t\t\t\t\t\t \n\t\t\t\t\t<\/p>\n<\/p><\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p><span><span><span style="font-family:\u5b8b\u4f53;">\u7ecf\u8fc7\u5982\u4e0a\u64cd\u4f5c\u540e\uff0c\u76f8\u5e94\u7684\u5957\u63a5\u5b57\u7ed3\u6784<\/span><span>sock<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4f1a\u901a\u8fc7<\/span><span>raw_v4_hash()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u51fd\u6570\u94fe\u5230<\/span><span>raw_v4_htable<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u94fe\u8868\u4e2d\uff0c\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u62a5\u6587\u63a5\u6536\u65f6\u9700\u8981\u4f7f\u7528\u5230<\/span><span>raw_v4_htable<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u3002\u5982\u56fe<\/span><span>5<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6240\u793a\uff0c\u5171\u521b\u5efa\u4e86<\/span><span>3<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e2a\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\uff0c\u534f\u8bae\u7c7b\u578b\u5206\u522b\u4e3a<\/span><a name="OLE_LINK23"><\/a><a name="OLE_LINK22"><\/a><span><span><span>IPPROTO_TCP<\/span><\/span><\/span><\/span><\/span><span><\/span><span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u3001<\/span><span>IPPROTO_ICMP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u548c<\/span><span>89<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u3002<\/span><\/span><\/span> <\/p>\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t<span><span><span style="font-family:\u5b8b\u4f53;font-size:9pt;"><a href="http:\/\/blog.chinaunix.net\/attachment\/201210\/27\/27074062_1351344697mNsH.jpg" target="_blank"><img title="5" alt="5" src="http:\/\/blog.chinaunix.net\/attachment\/201210\/27\/27074062_1351344698zM2X.jpg" border="0" height="236" width="345" \/><\/a> <\/span><\/span><\/span>\n<\/p>\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t<span><span><span style="font-family:\u5b8b\u4f53;font-size:9pt;">\u56fe<\/span><\/span><\/span><span><span><span style="font-size:9pt;">5<span>  <\/span>raw_v4_htable<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;font-size:9pt;">\u94fe\u8868<\/span><\/span><\/span><span><span><span style="font-size:9pt;"> <\/span><\/span><\/span>\n<\/p>\n<p class="MsoNormal">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p>\n\t \n<\/p>\n<p><span><span><span style="line-height:173%;font-size:10.5pt;">2.3.2<span>  <\/span><\/span><\/span><\/span><span><span><span style="line-height:173%;font-family:\u5b8b\u4f53;font-size:10.5pt;">\u62a5\u6587\u63a5\u6536<\/span><\/span><\/span><span><span><span style="line-height:173%;font-size:10.5pt;"> <\/span><\/span><\/span> <\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span style="font-family:\u5b8b\u4f53;">\u7f51\u5361\u9a71\u52a8\u6536\u5230\u62a5\u6587\u540e\u5728\u8f6f\u4e2d\u65ad\u4e0a\u4e0b\u6587\u7531<\/span><span>netif_receive_skb()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u5904\u7406\uff0c\u5bf9\u4e8e<\/span><span>IP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u62a5\u6587\u4e14\u76ee\u7684\u5730\u5740\u4e3a\u672c\u673a\u7684\u4f1a\u7531<\/span><span>ip_rcv()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6700\u7ec8\u8c03\u7528<\/span><span>ip_local_deliver_finish()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u51fd\u6570\u3002<\/span><span>ip_local_deliver_finish()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e3b\u8981\u529f\u80fd\u7684\u4ee3\u7801\u7247\u6bb5\u5982\u4e0b\uff0c\u5148\u6839\u636e\u62a5\u6587\u7684<\/span><span>L4<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u5c42\u534f\u8bae\u7c7b\u578b<\/span><span>hash<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u503c\u5728\u56fe<\/span><span>5<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e2d\u7684<\/span><span>raw_v4_htable<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u8868\u4e2d\u67e5\u627e\u662f\u5426\u6709\u5339\u914d\u7684<\/span><span>sock<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u3002\u5982\u679c\u6709\u5339\u914d\u7684<\/span><span>sock<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7ed3\u6784\uff0c\u5c31\u8fdb\u4e00\u6b65\u8c03\u7528<\/span><span>raw_v4_input()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u5904\u7406\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u3002\u4e0d\u7ba1\u662f\u5426\u6709\u539f\u59cb\u5957\u63a5\u5b57\u8981\u5904\u7406\uff0c\u8be5\u62a5\u6587\u90fd\u4f1a\u8d70\u540e\u7eed\u7684\u534f\u8bae\u6808\u5904\u7406\u6d41\u7a0b\u3002\u5373\u4f1a\u7ee7\u7eed\u5339\u914d<\/span><span>inet_protos[]<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6570\u7ec4\uff0c\u6839\u636e<\/span><span>L4<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u5c42\u534f\u8bae\u7c7b\u578b\u8d70<\/span><span>TCP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u3001<\/span><span>UDP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u3001<\/span><span>ICMP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7b49\u4e0d\u540c\u5904\u7406\u6d41\u7a0b\u3002<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t\n<\/p>\n<table cellpadding="0" cellspacing="0" width="100%">\n<tbody>\n<tr>\n<td>\n<div>\n<p class="MsoNormal">\n\t\t\t\t\t\t<span style="font-size:9pt;"><span>         <br \/>\n<\/span><\/span>\n\t\t\t\t\t<\/p>\n<div>\n<div id="code828" class="codeText">\n<ol class="dp-css">\n<li>\n\t\t\t\t\t\t\t\t\t<span style="color:#000000;">\u2026\u2026 <br \/>\n<\/span>\n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\thash <span style="color:#0000cc;">=<\/span> protocol <span style="color:#0000cc;">&<\/span> <span style="color:#0000cc;">(<\/span>MAX_INET_PROTOS <span style="color:#0000cc;">–<\/span> 1<span style="color:#0000cc;">)<\/span><span style="color:#0000cc;">;<\/span> <span style="color:#0000cc;">\/<\/span><span style="color:#0000cc;">\/<\/span>\u6839\u636e\u62a5\u6587\u534f\u8bae\u7c7b\u578b\u53d6hash\u503c \n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\traw_sk <span style="color:#0000cc;">=<\/span> sk_head<span style="color:#0000cc;">(<\/span><span style="color:#0000cc;">&<\/span>raw_v4_htable<span style="color:#0000cc;">[<\/span>hash<span style="color:#0000cc;">]<\/span><span style="color:#0000cc;">)<\/span><span style="color:#0000cc;">;<\/span> <span style="color:#0000cc;">\/<\/span><span style="color:#0000cc;">\/<\/span>\u5728raw_v4_htable\u4e2d\u67e5\u627e \n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t\u2026\u2026 \n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t<span style="color:#0000ff;">if<\/span> <span style="color:#0000cc;">(<\/span>raw_sk <span style="color:#0000cc;">&<\/span><span style="color:#0000cc;">&<\/span> <span style="color:#0000cc;">!<\/span>raw_v4_input<span style="color:#0000cc;">(<\/span>skb<span style="color:#0000cc;">,<\/span> skb<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span>nh<span style="color:#0000cc;">.<\/span>iph<span style="color:#0000cc;">,<\/span> hash<span style="color:#0000cc;">)<\/span><span style="color:#0000cc;">)<\/span> <span style="color:#0000cc;">\/<\/span><span style="color:#0000cc;">\/<\/span>\u5904\u7406\u539f\u59cb\u5957\u63a5\u5b57 \n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t\u2026\u2026 \n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t<span style="color:#0000ff;">if<\/span> <span style="color:#0000cc;">(<\/span><span style="color:#0000cc;">(<\/span>ipprot <span style="color:#0000cc;">=<\/span> rcu_dereference<span style="color:#0000cc;">(<\/span>inet_protos<span style="color:#0000cc;">[<\/span>hash<span style="color:#0000cc;">]<\/span><span style="color:#0000cc;">)<\/span><span style="color:#0000cc;">)<\/span> <span style="color:#0000cc;">!<\/span><span style="color:#0000cc;">=<\/span> <span style="color:#0000ff;">NULL<\/span><span style="color:#0000cc;">)<\/span> <span style="color:#0000cc;">{<\/span> <span style="color:#0000cc;">\/<\/span><span style="color:#0000cc;">\/<\/span>\u5339\u914dinet_protos<span style="color:#0000cc;">[<\/span><span style="color:#0000cc;">]<\/span>\u6570\u7ec4 \n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t        \u2026\u2026 \n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t        ret <span style="color:#0000cc;">=<\/span> ipprot<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span>handler<span style="color:#0000cc;">(<\/span>skb<span style="color:#0000cc;">)<\/span><span style="color:#0000cc;">;<\/span> <span style="color:#0000cc;">\/<\/span><span style="color:#0000cc;">\/<\/span>\u8c03\u7528\u4f20\u8f93\u5c42\u5904\u7406\u51fd\u6570 \n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t        \u2026\u2026 \n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t<span style="color:#0000cc;">}<\/span> <span style="color:#0000ff;">else<\/span> <span style="color:#0000cc;">{<\/span> <span style="color:#0000cc;">\/<\/span><span style="color:#0000cc;">\/<\/span>\u5982\u679c\u5728inet_protos<span style="color:#0000cc;">[<\/span><span style="color:#0000cc;">]<\/span>\u6570\u7ec4\u4e2d\u672a\u5339\u914d\u5230\uff0c\u5219\u91ca\u653e\u62a5\u6587\n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t        \u2026\u2026 \n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t        kfree_skb<span style="color:#0000cc;">(<\/span>skb<span style="color:#0000cc;">)<\/span><span style="color:#0000cc;">;<\/span> \n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t<span style="color:#0000cc;">}<\/span> \n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t\u2026\u2026\n\t\t\t\t\t\t\t\t<\/li>\n<\/ol><\/div>\n<\/p><\/div>\n<p class="MsoNormal">\n\t\t\t\t\t\t \n\t\t\t\t\t<\/p>\n<\/p><\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p><span><span><span style="font-family:\u5b8b\u4f53;">\u5982\u56fe<\/span><span>6<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6240\u793a\u7684<\/span><span>inet_protos[]<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6570\u7ec4\uff0c\u6bcf\u9879\u7531<\/span><span>net_protocol<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7ed3\u6784\u7ec4\u6210\u3002\u8868\u793a\u4e00\u4e2a\u534f\u8bae\uff08\u5305\u62ec\u4f20\u8f93\u5c42\u534f\u8bae\u548c\u7f51\u7edc\u5c42\u9644\u5c5e\u534f\u8bae\uff09\u7684\u63a5\u6536\u5904\u7406\u51fd\u6570\u96c6\uff0c\u4e00\u822c\u5305\u62ec\u4e00\u4e2a\u6b63\u5e38\u63a5\u6536\u51fd\u6570\u548c\u4e00\u4e2a\u51fa\u9519\u63a5\u6536\u51fd\u6570\u3002\u56fe\u4e2d<\/span><span>TCP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u3001<\/span><span>UDP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u548c<\/span><span>ICMP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u534f\u8bae\u7684\u63a5\u6536\u5904\u7406\u51fd\u6570\u5206\u522b\u4e3a<\/span><span>tcp_v4_rcv()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u3001<\/span><span>udp_rcv()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u548c<\/span><span>icmp_rcv()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u3002\u5982\u679c\u5728<\/span><span>inet_protos[]<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6570\u7ec4\u4e2d\u672a\u914d\u7f6e\u5230\u76f8\u5e94\u7684<\/span><span>net_protocol<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7ed3\u6784\uff0c\u62a5\u6587\u5c31\u4f1a\u88ab\u4e22\u5f03\u6389\u3002\u6bd4\u5982<\/span><span>OSPF<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u62a5\u6587\uff08\u534f\u8bae\u7c7b\u578b\u4e3a<\/span><span>89<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\uff09\u5728<\/span><span>inet_protos[]<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6570\u7ec4\u4e2d\u6ca1\u6709\u76f8\u5e94\u7684\u9879\uff0c\u5185\u6838\u4f1a\u5c06\u5176\u4e22\u5f03\u6389\uff0c\u8fd9\u79cd\u62a5\u6587\u53ea\u80fd\u63d0\u4f9b\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u63a5\u6536\u5230\u7528\u6237\u6001\u6765\u5904\u7406\u3002<\/span><\/span><\/span> <\/p>\n<p style="text-align:center;" class="MsoNormal" align="center">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p style="text-align:center;text-indent:21pt;" class="MsoNormal" align="center">\n\t<span><span><span style="font-family:\u5b8b\u4f53;font-size:9pt;"><a href="http:\/\/blog.chinaunix.net\/attachment\/201210\/27\/27074062_1351344698T2SA.jpg" target="_blank"><img title="6" alt="6" src="http:\/\/blog.chinaunix.net\/attachment\/201210\/27\/27074062_1351344700rTaH.jpg" border="0" height="305" width="536" \/><\/a> <\/span><\/span><\/span>\n<\/p>\n<p style="text-align:center;text-indent:21pt;" class="MsoNormal" align="center">\n\t<span><span><span style="font-family:\u5b8b\u4f53;font-size:9pt;">\u56fe<\/span><\/span><\/span><span><span><span style="font-size:9pt;">6<span>  <\/span>inet_protos[]<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;font-size:9pt;">\u6570\u7ec4\u7ed3\u6784<\/span><\/span><\/span><span><span><span style="font-size:9pt;"> <\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p>\n\t<span><span><span style="font-family:\u5b8b\u4f53;">    \u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u7684\u603b\u4f53\u63a5\u6536\u6d41\u7a0b\u5982\u4e0b\uff0c\u6700\u7ec8\u4f1a\u5c06<\/span><span>skb<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6302\u5230\u76f8\u5e94\u5957\u63a5\u5b57\u4e0a\uff0c\u5e76\u5524\u9192\u7528\u6237\u6001\u8fdb\u7a0b\u8bfb\u53d6\u62a5\u6587\u6570\u636e\u3002<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span style="font-family:\u5b8b\u4f53;">\u7f51\u5361\u9a71\u52a8<\/span><span>->netif_receive_skb()->ip_rcv()->ip_rcv_finish()->ip_local_deliver()->ip_local<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span>_deliver_finish()->raw_v4_input()->raw_rcv()->raw_rcv_skb()->sock_queue_rcv_skb()<\/span><\/span><\/span>\n<\/p>\n<p class="MsoNormal">\n\t\n<\/p>\n<table cellpadding="0" cellspacing="0" width="100%">\n<tbody>\n<tr>\n<td>\n<div>\n\t\t\t\t\t<\/p>\n<div>\n<div id="code281" class="codeText">\n<ol class="dp-css">\n<li>\n\t\t\t\t\t\t\t\t\t<span style="color:#000000;">\u2026\u2026 <br \/>\n<\/span>\n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\tskb_queue_tail<span style="color:#0000cc;">(<\/span><span style="color:#0000cc;">&<\/span>sk<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span>sk_receive_queue<span style="color:#0000cc;">,<\/span> skb<span style="color:#0000cc;">)<\/span><span style="color:#0000cc;">;<\/span> <span style="color:#0000cc;">\/<\/span><span style="color:#0000cc;">\/<\/span>\u6302\u5230\u63a5\u6536\u961f\u5217 \n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t<span style="color:#0000ff;">if<\/span> <span style="color:#0000cc;">(<\/span><span style="color:#0000cc;">!<\/span>sock_flag<span style="color:#0000cc;">(<\/span>sk<span style="color:#0000cc;">,<\/span> SOCK_DEAD<span style="color:#0000cc;">)<\/span><span style="color:#0000cc;">)<\/span> \n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t        sk<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span>sk_data_ready<span style="color:#0000cc;">(<\/span>sk<span style="color:#0000cc;">,<\/span> skb_len<span style="color:#0000cc;">)<\/span><span style="color:#0000cc;">;<\/span> <span style="color:#0000cc;">\/<\/span><span style="color:#0000cc;">\/<\/span>\u5524\u9192\u7528\u6237\u6001\u8fdb\u7a0b \n\t\t\t\t\t\t\t\t<\/li>\n<li>\n\t\t\t\t\t\t\t\t\t\u2026\u2026\n\t\t\t\t\t\t\t\t<\/li>\n<\/ol><\/div>\n<\/p><\/div>\n<\/p><\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p class="MsoNormal">\n\t<span><span><span><span>       <\/span><\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e0a\u9762\u4ecb\u7ecd\u4e86\u62a5\u6587\u63a5\u6536\u5728\u8f6f\u4e2d\u65ad\u7684\u5904\u7406\u6d41\u7a0b\uff0c\u4e0b\u9762\u4ecb\u7ecd\u7528\u6237\u6001\u8fdb\u7a0b\u8bfb\u53d6\u62a5\u6587\u662f\u5982\u4f55\u5b9e\u73b0\u7684\u3002\u7528\u6237\u6001\u7684<\/span><span>recvmsg()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6700\u7ec8\u4f1a\u8c03\u7528<\/span><span>raw_recvmsg()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\uff0c\u540e\u8005\u518d\u8c03\u7528<\/span><span>skb_recv_datagram<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u3002\u5982\u679c\u5957\u63a5\u5b57\u63a5\u6536\u961f\u5217<\/span><span>sk->sk_receive_queue<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e2d\u6709\u62a5\u6587\u5c31\u53d6<\/span><span>skb<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u5e76\u8fd4\u56de\u3002\u5426\u5219\u8c03\u7528<\/span><span>wait_for_packet()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7b49\u5f85\uff0c\u76f4\u5230\u5185\u6838\u8f6f\u4e2d\u65ad\u6536\u5230\u62a5\u6587\u5e76\u5524\u9192\u7528\u6237\u6001\u8fdb\u7a0b\u3002<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span>sys_recvmsg()->sock_recvmsg()->\u2026->sock_common_recvmsg()->raw_recvmsg()<\/span><\/span><\/span>\n<\/p>\n<p class="MsoNormal">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p>\n\t \n<\/p>\n<p><span><span><span style="line-height:173%;font-size:10.5pt;">2.3.3<span>  <\/span><\/span><\/span><\/span><span><span><span style="line-height:173%;font-family:\u5b8b\u4f53;font-size:10.5pt;">\u62a5\u6587\u53d1\u9001<\/span><\/span><\/span><span><span><span style="line-height:173%;font-size:10.5pt;"> <\/span><\/span><\/span> <\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span style="font-family:\u5b8b\u4f53;">\u7528\u6237\u6001\u8c03\u7528<\/span><span>sendto()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6216<\/span><span>sendmsg()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u53d1\u9001\u62a5\u6587\u7684\u5185\u6838\u6001\u5904\u7406\u6d41\u7a0b\u5982\u4e0b\uff0c\u6700\u7ec8\u7531<\/span><span>raw_sendmsg()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u8fdb\u884c\u53d1\u9001\u3002<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span>sys_sendto()->sock_sendmsg()->__sock_sendmsg()->inet_sendmsg()->raw_sendmsg()<\/span><\/span><\/span>\n<\/p>\n<p class="MsoNormal">\n\t<span><span><span><span>    <\/span><\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6b64\u51fd\u6570\u5148\u8fdb\u884c\u4e00\u4e9b\u53c2\u6570\u5408\u6cd5\u6027\u68c0\u6d4b\uff0c\u7136\u540e\u8c03\u7528<\/span><span>ip_route_output_slow()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u8fdb\u884c\u9009\u8def\u3002\u9009\u8def\u6210\u529f\u540e\u4e3b\u8981\u6267\u884c\u5982\u4e0b\u4ee3\u7801\u7247\u6bb5\uff0c\u6839\u636e<\/span><span>inet->hdrincl<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u662f\u5426\u8bbe\u7f6e\u8d70\u4e0d\u540c\u7684\u6d41\u7a0b\u3002<\/span><\/span><\/span><span><span><span>raw_send_hdrinc()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u51fd\u6570\u8868\u793a\u7528\u6237\u6001\u53d1\u9001\u7684\u6570\u636e\u4e2d\u9700\u8981\u5305\u542b<\/span><\/span><\/span><span><span><span>IP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u9996\u90e8\uff0c\u5373\u7531\u8c03\u7528\u8005\u5728\u53d1\u9001\u65f6\u81ea\u884c\u6784\u9020<\/span><\/span><\/span><span><span><span>IP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u9996\u90e8\u3002\u5982\u679c<\/span><span>inet->hdrincl<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u672a\u7f6e\u4f4d\uff0c\u8868\u793a\u5185\u6838\u4f1a\u6784\u9020<\/span><span>IP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u9996\u90e8\uff0c\u5373\u8c03\u7528\u8005\u53d1\u9001\u7684\u6570\u636e\u4e2d\u4e0d\u5305\u542b<\/span><span>IP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u9996\u90e8\u3002\u4e0d\u7ba1\u8d70\u54ea\u4e2a\u6d41\u7a0b\uff0c\u6700\u7ec8\u90fd\u4f1a\u7ecf\u8fc7<\/span><span>ip_output()->ip_finish_output()->\u2026->dev_queue_xmit()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u5c06\u62a5\u6587\u4ea4\u7ed9\u7f51\u5361\u9a71\u52a8\u7684\u53d1\u9001\u51fd\u6570\u53d1\u9001\u51fa\u53bb\u3002<\/span><\/span><\/span>\n<\/p>\n<p class="MsoNormal">\n\t<span><span><span style="font-family:\u5b8b\u4f53;"><\/span><\/span><\/span> \n<\/p>\n<div>\n<div id="code796" class="codeText">\n<ol class="dp-css">\n<li>\n\t\t\t\t<span style="color:#000000;">\u2026\u2026 <br \/>\n<\/span>\n\t\t\t<\/li>\n<li>\n\t\t\t\t<span style="color:#0000ff;">if<\/span> <span style="color:#0000cc;">(<\/span>inet<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span>hdrincl<span style="color:#0000cc;">)<\/span> <span style="color:#0000cc;">{<\/span> <span style="color:#0000cc;">\/<\/span><span style="color:#0000cc;">\/<\/span>\u8c03\u7528\u8005\u8981\u6784\u9020IP\u9996\u90e8 \n\t\t\t<\/li>\n<li>\n\t\t\t\t        <span style="color:#ff0000;">err<\/span> <span style="color:#0000cc;">=<\/span> raw_send_hdrinc<span style="color:#0000cc;">(<\/span>sk<span style="color:#0000cc;">,<\/span> msg<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span>msg_iov<span style="color:#0000cc;">,<\/span> <span style="color:#ff0000;">len<\/span><span style="color:#0000cc;">,<\/span> \n\t\t\t<\/li>\n<li>\n\t\t\t\t                              rt<span style="color:#0000cc;">,<\/span> msg<span style="color:#0000cc;">–<\/span><span style="color:#0000cc;">><\/span>msg_flags<span style="color:#0000cc;">)<\/span><span style="color:#0000cc;">;<\/span> \n\t\t\t<\/li>\n<li>\n\t\t\t\t<span style="color:#0000cc;">}<\/span> <span style="color:#0000ff;">else<\/span> <span style="color:#0000cc;">{<\/span> \n\t\t\t<\/li>\n<li>\n\t\t\t\t        \u2026\u2026 <span style="color:#0000cc;">\/<\/span><span style="color:#0000cc;">\/<\/span>\u7531\u5185\u6838\u6784\u9020IP\u9996\u90e8 \n\t\t\t<\/li>\n<li>\n\t\t\t\t       <span style="color:#ff0000;">err<\/span> <span style="color:#0000cc;">=<\/span> ip_push_pending_frames<span style="color:#0000cc;">(<\/span>sk<span style="color:#0000cc;">)<\/span><span style="color:#0000cc;">;<\/span> \n\t\t\t<\/li>\n<li>\n\t\t\t\t<span style="color:#0000cc;">}<\/span> \n\t\t\t<\/li>\n<li>\n\t\t\t\t\u2026\u2026\n\t\t\t<\/li>\n<\/ol><\/div>\n<\/div>\n<p class="MsoNormal">\n\t<span><span><span style="font-family:\u5b8b\u4f53;">   \u6ce8\uff1a<\/span><span>inet->hdrincl<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7f6e\u4f4d\u8868\u793a\u7528\u6237\u6001\u53d1\u9001\u7684\u6570\u636e\u4e2d\u8981\u5305\u542b<\/span><span>IP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u9996\u90e8\uff0c<\/span><span>inet->hdrincl<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u5728\u4ee5\u4e0b\u4e24\u79cd\u60c5\u51b5\u4e0b\u88ab\u7f6e\u4f4d\u3002<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span><span>    <\/span>a). <\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7ed9\u5957\u63a5\u5b57\u8bbe\u7f6e<\/span><span>IP_HDRINCL<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u9009\u9879<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span><span>       <\/span><span>   <\/span>setsockopt (sockfd, IPPROTO_IP, IP_HDRINCL, &val, sizeof(val))<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span><span>    <\/span>b). <\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u8c03\u7528<\/span><span>socket()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u521b\u5efa\u5957\u63a5\u5b57\u65f6\uff0c\u7b2c\u4e09\u4e2a\u53c2\u6570\u6307\u5b9a\u4e3a<\/span><span>IPPROTO_RAW<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\uff0c\u89c1<\/span><span>2.3.1<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u8282\u3002<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span><span>       <\/span><span>   <\/span>socktet(PF_INET, SOCK_RAW, IPPROTO_RAW)<\/span><\/span><\/span>\n<\/p>\n<p class="MsoNormal">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p>\n\t \n<\/p>\n<p><span><span><span style="line-height:173%;font-size:10.5pt;">2.3.4<span>  <\/span><\/span><\/span><\/span><span><span><span style="line-height:173%;font-family:\u5b8b\u4f53;font-size:10.5pt;">\u5176\u5b83<\/span><\/span><\/span><span><span><span style="line-height:173%;font-size:10.5pt;"> <\/span><\/span><\/span> <\/p>\n<p style="text-indent:-18pt;margin-left:18pt;" class="MsoListParagraph">\n\t<span><span><span><span>a)<span style="line-height:normal;font-style:normal;font-size:7pt;font-weight:normal;">       <\/span><\/span><\/span><span style="font-family:\u5b8b\u4f53;">\u5957\u63a5\u5b57\u7ed1\u5b9a<\/span><\/span><\/span>\n<\/p>\n<p style="margin-left:18pt;" class="MsoNormal">\n\t<span><span><span style="font-family:\u5b8b\u4f53;">\u82e5\u539f\u59cb\u5957\u63a5\u5b57\u8c03\u7528<\/span><span>bind()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7ed1\u5b9a\u4e86\u4e00\u4e2a\u5730\u5740\uff0c\u5219\u8be5\u5957\u63a5\u53e3\u53ea\u80fd\u6536\u5230\u76ee\u7684<\/span><span>IP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u5730\u5740\u4e0e\u7ed1\u5b9a\u5730\u5740\u76f8\u5339\u914d\u7684\u62a5\u6587\u3002\u5185\u6838\u7684\u5177\u4f53\u5b9e\u73b0\u662f<\/span><span>raw_bind()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\uff0c\u5c06<\/span><span>inet->rcv_saddr<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u8bbe\u7f6e\u4e3a\u7ed1\u5b9a\u5730\u5740\u3002\u5728\u539f\u59cb\u5957\u63a5\u5b57\u63a5\u6536\u65f6\uff0c<\/span><span>__raw_v4_lookup()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u5728\u8bbe\u7f6e\u4e86<\/span><span>inet->rcv_saddr<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u5b57\u6bb5\u7684\u60c5\u51b5\u4e0b\uff0c\u4f1a\u5224\u65ad\u8be5\u5b57\u6bb5\u662f\u5426\u4e0e\u62a5\u6587\u76ee\u7684<\/span><span>IP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u5730\u5740\u76f8\u540c\u3002<\/span><\/span><\/span>\n<\/p>\n<p style="margin-left:18pt;" class="MsoNormal">\n\t<span><span><span>sys_bind()->inet_bind()->raw_bind()<\/span><\/span><\/span>\n<\/p>\n<p class="MsoNormal">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p>\n\t<span><span><span><span>b)<span style="line-height:normal;font-style:normal;font-size:7pt;font-weight:normal;">      <\/span><\/span><\/span><span style="font-family:\u5b8b\u4f53;">\u4fe1\u606f\u67e5\u770b<\/span><\/span><\/span>\n<\/p>\n<p style="margin-left:18pt;" class="MsoNormal">\n\t<span><span><span style="font-family:\u5b8b\u4f53;">\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u7684\u4fe1\u606f\u53ef\u901a\u8fc7<\/span><span>\/proc\/net\/raw<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u8fdb\u884c\u67e5\u770b\u3002\u5982\u4e0b\u4e3a\u56fe<\/span><span>5<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6240\u521b\u5efa\u7684<\/span><span>3<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e2a\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u7684\u4fe1\u606f\uff0c\u53ef\u4ee5\u67e5\u770b\u5230\u521b\u5efa\u5957\u63a5\u5b57\u65f6\u6307\u5b9a\u7684\u534f\u8bae\u7c7b\u578b\u3001\u7ed1\u5b9a\u7684\u5730\u5740\u3001\u53d1\u9001\u548c\u63a5\u6536\u961f\u5217\u5df2\u4f7f\u7528\u7684\u7f13\u5b58\u5927\u5c0f\u7b49\u4fe1\u606f\u3002<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u8fd9\u4e9b\u4fe1\u606f\u5bf9\u4e8e\u5206\u6790\u548c\u5b9a\u4f4d\u95ee\u9898\u6709\u5e2e\u52a9\u3002<\/span><\/span><\/span>\n<\/p>\n<div>\n<div id="code218" class="codeText">\n<ol class="dp-css">\n<li>\n\t\t\t\tcat \/proc\/net\/raw\n\t\t\t<\/li>\n<li>\n\t\t\t\tsl local_address rem_address st tx_queue rx_queue tr tm->when retrnsmt uid timeout inode\n\t\t\t<\/li>\n<li>\n\t\t\t\t1: 00000000:0001 00000000:0000 07 00000000:00000000 00:00000000 00000000 0 0 1323 2 ffff8100070b2380\n\t\t\t<\/li>\n<li>\n\t\t\t\t6: 00000000:0006 00000000:0000 07 00000000:00000000 00:00000000 00000000 0 0 1322 2 ffff8100070b2080\n\t\t\t<\/li>\n<li>\n\t\t\t\t89: 00000000:0059 00000000:0000 07 00000000:00000000 00:00000000 00000000 0 0 1324 2 ffff8100070b2680\n\t\t\t<\/li>\n<\/ol><\/div>\n<\/div>\n<p class="MsoNormal">\n\t \n<\/p>\n<p class="MsoNormal">\n\t <span><span><span style="line-height:240%;font-family:\u5b8b\u4f53;font-size:14pt;">\u4e09\u3001\u5e94\u7528\u53ca\u6ce8\u610f\u4e8b\u9879<\/span><\/span><\/span><span><span><span style="line-height:240%;font-size:14pt;"> <\/span><\/span><\/span>\n<\/p>\n<p><span><span><span style="line-height:173%;font-size:12pt;">3.1<span>  \u4f7f\u7528<\/span><\/span><\/span><\/span><span><span><span style="line-height:173%;font-family:\u5b8b\u4f53;font-size:12pt;">\u94fe\u8def\u5c42\u539f\u59cb\u5957\u63a5\u5b57<\/span><\/span><\/span><span><span><span style="line-height:173%;font-size:12pt;"> <\/span><\/span><\/span> <\/p>\n<p class="MsoNormal">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p>\n\t<span><span><b><span style="font-family:\u5b8b\u4f53;">\u6ce8\u610f\u4e8b\u9879\uff1a<\/span><span> <\/span><\/b><\/span><\/span>\n<\/p>\n<p style="text-indent:-18pt;margin-left:18pt;" class="MsoListParagraph">\n\t<span><span><span><span>a)<span style="line-height:normal;font-style:normal;font-size:7pt;font-weight:normal;">       <\/span><\/span><\/span><span style="font-family:\u5b8b\u4f53;">\u5c3d\u91cf\u907f\u514d\u521b\u5efa\u8fc7\u591a\u539f\u59cb\u5957\u63a5\u5b57\uff0c\u4e14\u539f\u59cb\u5957\u63a5\u5b57\u8981\u5c3d\u91cf\u7ed1\u5b9a\u7f51\u5361\u3002\u56e0\u4e3a\u6536\u5230\u6bcf\u4e2a\u62a5\u6587\u9664\u4e86\u4f1a\u5c06\u5176\u5206\u53d1\u7ed9\u7ed1\u5b9a\u5728\u8be5\u7f51\u5361\u4e0a\u7684\u539f\u59cb\u5957\u63a5\u5b57\u5916\uff0c\u8fd8\u4f1a\u5206\u53d1\u7ed9\u6ca1\u6709\u7ed1\u5b9a\u7f51\u5361\u7684\u539f\u59cb\u5957\u63a5\u5b57\u3002\u5982\u679c\u539f\u59cb\u5957\u63a5\u5b57\u8f83\u591a\uff0c\u4e00\u4e2a\u62a5\u6587\u5c31\u4f1a\u5728\u8f6f\u4e2d\u65ad\u4e0a\u4e0b\u6587\u4e2d\u5206\u53d1\u591a\u6b21\uff0c\u9020\u6210\u5904\u7406\u65f6\u95f4\u8fc7\u957f\u3002<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:0cm;margin-left:18pt;" class="MsoListParagraph">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p>\n\t<span><span><span><span>b)<span style="line-height:normal;font-style:normal;font-size:7pt;font-weight:normal;">      <\/span><\/span><\/span><span style="font-family:\u5b8b\u4f53;">\u53d1\u5305\u548c\u6536\u5305\u5c3d\u91cf\u4f7f\u7528\u540c\u4e00\u4e2a\u539f\u59cb\u5957\u63a5\u5b57\u3002\u5982\u679c\u53d1\u5305\u4e0e\u6536\u5305\u4f7f\u7528\u4e24\u4e2a\u4e0d\u540c\u7684\u539f\u59cb\u5957\u63a5\u5b57\uff0c\u4f1a\u7531\u4e8e\u63a5\u6536\u62a5\u6587\u65f6\u5206\u53d1\u591a\u6b21\u800c\u5f71\u54cd\u6027\u80fd\u3002\u800c\u4e14\u7528\u4e8e\u53d1\u9001\u7684\u90a3\u4e2a\u5957\u63a5\u5b57\u7684\u63a5\u6536\u961f\u5217\u4e0a\u4e5f\u4f1a\u7f13\u5b58\u62a5\u6587\uff0c\u76f4\u81f3\u8fbe\u5230\u63a5\u6536\u961f\u5217\u5927\u5c0f\u9650\u5236\uff0c\u4f1a\u9020\u6210\u5185\u5b58\u6cc4\u9732\u3002<\/span><\/span><\/span>\n<\/p>\n<p class="MsoListParagraph">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p>\n\t<span><span><span><span>c)<span style="line-height:normal;font-style:normal;font-size:7pt;font-weight:normal;">       <\/span><\/span><\/span><span style="font-family:\u5b8b\u4f53;">\u82e5\u53ea\u63a5\u6536\u6307\u5b9a\u7c7b\u578b\u4e8c\u5c42\u62a5\u6587\uff0c\u5728\u8c03\u7528<\/span><span>socket()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u65f6\u6307\u5b9a\u7b2c\u4e09\u4e2a\u53c2\u6570\u7684\u534f\u8bae\u7c7b\u578b\uff0c\u800c\u6700\u597d\u4e0d\u8981\u4f7f\u7528<\/span><span>ETH_P_ALL<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u3002\u56e0\u4e3a<\/span><span>ETH_P_ALL<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4f1a\u63a5\u6536\u6240\u6709\u7c7b\u578b\u7684\u62a5\u6587\uff0c\u800c\u4e14\u8fd8\u4f1a\u5c06\u5916\u53d1\u62a5\u6587\u6536\u56de\u6765\uff0c\u8fd9\u6837\u5c31\u9700\u8981\u505a<\/span><span>BPF<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u8fc7\u6ee4\uff0c\u6bd4\u8f83\u5f71\u54cd\u6027\u80fd\u3002<\/span><\/span><\/span>\n<\/p>\n<p class="MsoNormal">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p>\n\t<span><span><span style="line-height:173%;font-size:12pt;"><\/span><\/span><\/span> \n<\/p>\n<p>\n\t<span><span><span style="line-height:173%;font-size:12pt;">3.2 <span> <\/span><\/span><\/span><\/span><span><span><span style="line-height:173%;font-family:\u5b8b\u4f53;font-size:12pt;">\u4f7f\u7528\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57<\/span><\/span><\/span><span><span><span style="line-height:173%;font-size:12pt;"> <\/span><\/span><\/span>\n<\/p>\n<p class="MsoNormal">\n\t<span><span><b><span style="font-family:\u5b8b\u4f53;">\u6ce8\u610f\u4e8b\u9879\uff1a<\/span><span> <\/span><\/b><\/span><\/span>\n<\/p>\n<p style="text-indent:-18pt;margin-left:18pt;" class="MsoListParagraph">\n\t<span><span><span><span>a)<span style="line-height:normal;font-style:normal;font-size:7pt;font-weight:normal;">       <\/span><\/span><\/span><span style="font-family:\u5b8b\u4f53;">\u7531\u4e8e<\/span><span>IP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u62a5\u6587\u7684\u91cd\u7ec4\u662f\u5728\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u63a5\u6536\u6d41\u7a0b\u4e4b\u524d\u6267\u884c\u7684\uff0c\u6240\u4ee5\u8be5\u539f\u59cb\u5957\u63a5\u5b57\u4e0d\u80fd\u63a5\u6536\u5230<\/span><span>UDP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u548c<\/span><span>TCP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7684\u5206\u7ec4\u6570\u636e\u3002<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:0cm;margin-left:18pt;" class="MsoListParagraph">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p>\n\t<span><span><span><span>b)<span style="line-height:normal;font-style:normal;font-size:7pt;font-weight:normal;">      <\/span><\/span><\/span><span style="font-family:\u5b8b\u4f53;">\u82e5\u539f\u59cb\u5957\u63a5\u5b57\u5df2\u7531<\/span><span>bind()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7ed1\u5b9a\u4e86\u67d0\u4e2a\u672c\u5730<\/span><span>IP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u5730\u5740\uff0c\u90a3\u4e48\u53ea\u6709\u76ee\u7684<\/span><span>IP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u5730\u5740\u4e0e\u7ed1\u5b9a\u5730\u5740\u5339\u914d\u7684\u62a5\u6587\uff0c\u624d\u80fd\u9012\u9001\u5230\u8fd9\u4e2a\u5957\u63a5\u53e3\u4e0a\u3002<\/span><\/span><\/span>\n<\/p>\n<p class="MsoListParagraph">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p>\n\t<span><span><span><span>c)<span style="line-height:normal;font-style:normal;font-size:7pt;font-weight:normal;">       <\/span><\/span><\/span><span style="font-family:\u5b8b\u4f53;">\u82e5\u539f\u59cb\u5957\u63a5\u5b57\u5df2\u7531<\/span><span>connect()<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6307\u5b9a\u4e86\u67d0\u4e2a\u8fdc\u5730<\/span><span>IP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u5730\u5740\uff0c\u90a3\u4e48\u53ea\u6709\u6e90<\/span><span>IP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u5730\u5740\u4e0e\u8fd9\u4e2a\u5df2\u8fde\u63a5\u5730\u5740\u5339\u914d\u7684\u62a5\u6587\uff0c\u624d\u80fd\u9012\u9001\u5230\u8fd9\u4e2a\u5957\u63a5\u53e3\u4e0a\u3002<\/span><\/span><\/span>\n<\/p>\n<p class="MsoNormal">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p>\n\t \n<\/p>\n<p><span><span><span style="line-height:173%;font-size:12pt;">3.3<span>  <\/span><\/span><\/span><\/span><span><span><span style="line-height:173%;font-family:\u5b8b\u4f53;font-size:12pt;">\u7f51\u7edc\u8bca\u65ad\u5de5\u5177\u4f7f\u7528\u539f\u59cb\u5957\u63a5\u5b57<\/span><\/span><\/span><span><span><span style="line-height:173%;font-size:12pt;"> <\/span><\/span><\/span> <\/p>\n<p style="text-indent:21pt;" class="MsoNormal">\n\t<span><span><span style="font-family:\u5b8b\u4f53;">\u5f88\u591a\u7f51\u7edc\u8bca\u65ad\u5de5\u5177\u4e5f\u662f\u5229\u7528\u539f\u59cb\u5957\u63a5\u5b57\u6765\u5b9e\u73b0\u7684\uff0c\u7ecf\u5e38\u4f1a\u4f7f\u7528\u5230\u7684\u6709<\/span><span>tcpdump, ping<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u548c<\/span><span>traceroute<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7b49\u3002<\/span><\/span><\/span>\n<\/p>\n<p>\n\t<span><span><b><span>tcpdump <\/span><\/b><\/span><\/span>\n<\/p>\n<p style="margin-left:21pt;" class="MsoNormal">\n\t<span><span><span style="font-family:\u5b8b\u4f53;">\u8be5\u5de5\u5177\u7528\u4e8e\u622a\u83b7\u7f51\u53e3\u4e0a\u7684\u62a5\u6587\u6d41\u91cf\u3002\u5176\u5b9e\u73b0\u539f\u7406\u662f\u521b\u5efa<\/span><span>ETH_P_ALL<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7c7b\u578b\u7684\u94fe\u8def\u5c42\u539f\u59cb\u5957\u63a5\u5b57\uff0c\u8bfb\u53d6\u548c\u89e3\u6790\u62a5\u6587\u6570\u636e\u5e76\u5c06\u4fe1\u606f\u663e\u793a\u51fa\u6765\u3002<\/span><\/span><\/span>\n<\/p>\n<p class="MsoNormal">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p>\n\t<span><span><b><span>ping <\/span><\/b><\/span><\/span>\n<\/p>\n<p style="margin-left:21pt;" class="MsoNormal">\n\t<span><span><span style="font-family:\u5b8b\u4f53;">\u8be5\u5de5\u5177\u7528\u4e8e\u68c0\u67e5\u7f51\u7edc\u8fde\u63a5\u3002\u5176\u5b9e\u73b0\u539f\u7406\u662f\u521b\u5efa\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\uff0c\u6307\u5b9a\u534f\u8bae\u7c7b\u578b\u4e3a<\/span><span>IPPROTO_ICMP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u3002\u68c0\u6d4b\u65b9\u6784\u9020<\/span><span>ICMP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u56de\u5c04\u8bf7\u6c42\u62a5\u6587\uff08\u7c7b\u578b\u4e3a<\/span><span>ICMP_ECHO<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\uff09\uff0c\u6839\u636e<\/span><span>ICMP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u534f\u8bae\u5b9e\u73b0\uff0c\u88ab\u68c0\u6d4b\u65b9\u6536\u5230\u8be5\u8bf7\u6c42\u62a5\u6587\u540e\u4f1a\u54cd\u5e94\u4e00\u4e2a<\/span><span>ICMP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u56de\u5c04\u5e94\u7b54\u62a5\u6587\uff08\u7c7b\u578b\u4e3a<\/span><span>ICMP_ECHOREPLY<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\uff09\u3002\u7136\u540e\u68c0\u6d4b\u65b9\u901a\u8fc7\u539f\u59cb\u5957\u63a5\u5b57\u8bfb\u53d6\u5e76\u89e3\u6790\u5e94\u7b54\u62a5\u6587\uff0c\u5e76\u663e\u793a\u51fa\u5e8f\u53f7\u3001<\/span><span>TTL<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7b49\u4fe1\u606f\u3002<\/span><\/span><\/span>\n<\/p>\n<p class="MsoNormal">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p>\n\t<span><span><b><span>traceroute <\/span><\/b><\/span><\/span>\n<\/p>\n<p style="margin-left:21pt;" class="MsoNormal">\n\t<span><span><span style="font-family:\u5b8b\u4f53;">\u8be5\u5de5\u5177\u7528\u4e8e\u8ddf\u8e2a<\/span><span>IP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u62a5\u6587\u5728\u7f51\u7edc\u4e2d\u7684\u8def\u7531\u8fc7\u7a0b\u3002\u5176\u5b9e\u73b0\u539f\u7406\u4e5f\u662f\u521b\u5efa\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\uff0c\u6307\u5b9a\u534f\u8bae\u7c7b\u578b\u4e3a<\/span><span>IPPROTO_ICMP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u3002\u5047\u8bbe\u4ece<\/span><span>A<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e3b\u673a\u8def\u7531\u5230<\/span><span>D<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e3b\u673a\uff0c\u9700\u8981\u4f9d\u6b21\u7ecf\u8fc7<\/span><span>B<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e3b\u673a\u548c<\/span><span>C<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e3b\u673a\u3002\u4f7f\u7528<\/span><span>traceroute<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6765\u8ddf\u8e2a<\/span><span>A<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e3b\u673a\u5230<\/span><span>D<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e3b\u673a\u7684\u8def\u7531\u9014\u5f84\uff0c\u5177\u4f53\u6b65\u9aa4\u5982\u4e0b\uff0c\u5728\u6bcf\u6b21\u63a2\u6d4b\u8fc7\u7a0b\u4e2d\u4f1a\u663e\u793a\u5404\u8282\u70b9\u7684<\/span><span>IP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u3001\u65f6\u95f4\u7b49\u4fe1\u606f\u3002<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:-18pt;margin-left:39pt;" class="MsoListParagraph">\n\t<span><span><span><span>a)<span style="line-height:normal;font-style:normal;font-size:7pt;font-weight:normal;">       <\/span><\/span><\/span><span>A<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e3b\u673a\u4f7f\u7528\u666e\u901a\u7684<\/span><span>UDP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u5957\u63a5\u5b57\u5411\u76ee\u7684\u4e3b\u673a\u53d1\u9001<\/span><span>TTL<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e3a<\/span><span>1<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\uff08\u4f7f\u7528\u5957\u63a5\u53e3\u9009\u9879<\/span><span>IP_TTL<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u6765\u4fee\u6539\uff09\u7684<\/span><span>UDP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u62a5\u6587\uff1b<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:-18pt;margin-left:39pt;" class="MsoListParagraph">\n\t<span><span><span><span>b)<span style="line-height:normal;font-style:normal;font-size:7pt;font-weight:normal;">      <\/span><\/span><\/span><span>B<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e3b\u673a\u6536\u5230\u8be5<\/span><span>UDP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u62a5\u6587\u540e\uff0c\u7531\u4e8e<\/span><span>TTL<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e3a<\/span><span>1<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4f1a\u62d2\u7edd\u8f6c\u53d1\uff0c\u5e76\u4e14\u5411<\/span><span>A<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e3b\u673a\u53d1\u9001<\/span><span>code<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e3a<\/span><span>ICMP_EXC_TTL<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7684<\/span><span>ICMP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u62a5\u6587\uff1b<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:-18pt;margin-left:39pt;" class="MsoListParagraph">\n\t<span><span><span><span>c)<span style="line-height:normal;font-style:normal;font-size:7pt;font-weight:normal;">       <\/span><\/span><\/span><span>A<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e3b\u673a\u7528\u521b\u5efa\u7684\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u8bfb\u53d6\u5e76\u89e3\u6790<\/span><span>ICMP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u62a5\u6587\u3002\u5982\u679c<\/span><span>ICMP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u62a5\u6587<\/span><span>code<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u662f<\/span><span>ICMP_EXC_TTL<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\uff0c\u5c31\u5c06<\/span><span>UDP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u62a5\u6587\u7684<\/span><span>TTL<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u589e\u52a0<\/span><span>1<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u5e76\u56de\u5230\u6b65\u9aa4<\/span><span>a)<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7ee7\u7eed\u8fdb\u884c\u63a2\u6d4b\uff1b\u5982\u679c<\/span><span>ICMP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u62a5\u6587\u7684<\/span><span>code<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u662f<\/span><span>ICMP_PROT_UNREACH<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\uff0c\u8868\u793a<\/span><span>UDP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u62a5\u6587\u5230\u8fbe\u4e86\u76ee\u7684\u5730\u3002<\/span><\/span><\/span>\n<\/p>\n<p style="margin-left:39pt;" class="MsoNormal">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p>\n\t<span><span><span><span>       <\/span><span>       <\/span>A<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e3b\u673a\u2015<\/span><span>>B<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e3b\u673a\u2015<\/span><span>>C<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e3b\u673a\u2015<\/span><span>>D<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u4e3b\u673a<\/span><\/span><\/span>\n<\/p>\n<p class="MsoNormal">\n\t<span><span><span><\/span><\/span><\/span>\n<\/p>\n<p>\n\t<span><span><span style="line-height:240%;font-family:\u5b8b\u4f53;font-size:14pt;"><\/span><\/span><\/span> \n<\/p>\n<p>\n\t<span><span><span style="line-height:240%;font-family:\u5b8b\u4f53;font-size:14pt;">\u53c2\u8003\u8d44\u6599<\/span><\/span><\/span><span><span><span style="line-height:240%;font-size:14pt;"> <\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:-18pt;margin-left:18pt;" class="MsoListParagraph">\n\t<span><span><span><span>1.<span style="line-height:normal;font-style:normal;font-size:7pt;font-weight:normal;">       <\/span><\/span><\/span><span style="font-family:\u5b8b\u4f53;">\u300a<\/span><span>Linux<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u5185\u6838\u6e90\u7801\u5256\u6790\u2014\u2014<\/span><span>TCP\/IP<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u5b9e\u73b0\u300b<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:-18pt;margin-left:18pt;" class="MsoListParagraph">\n\t<span><span><span><span>2.<span style="line-height:normal;font-style:normal;font-size:7pt;font-weight:normal;">       <\/span><\/span><\/span><span style="font-family:\u5b8b\u4f53;">\u300a\u6df1\u5165\u7406\u89e3<\/span><span>Linux<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7f51\u7edc\u5185\u5e55\u300b<\/span><\/span><\/span>\n<\/p>\n<p style="text-indent:-18pt;margin-left:18pt;" class="MsoListParagraph">\n\t<span><span><span><span>3.<span style="line-height:normal;font-style:normal;font-size:7pt;font-weight:normal;">       <\/span><\/span><\/span><span style="font-family:\u5b8b\u4f53;">\u300a<\/span><span>UNIX<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7f51\u7edc\u7f16\u7a0b<\/span> <\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u7b2c<\/span><span>1<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u5377\uff1a\u5957\u63a5\u53e3<\/span><span>API<\/span><\/span><\/span><span><span><span style="font-family:\u5b8b\u4f53;">\u300b<\/span><\/span><\/span><\/p>\n<\/div>

\n\thttp:\/\/blog.chinaunix.net\/uid-27074062-id-3388166.html
\n <\/span><\/span><\/span>\n<\/p>\n

\n\t\u672c\u6587\u4eceIPV4<\/span>\u534f\u8bae\u6808\u539f\u59cb\u5957\u63a5\u5b57\u7684\u5206\u7c7b\u5165\u624b\uff0c\u8be6\u7ec6\u4ecb\u7ecd\u4e86\u94fe\u8def\u5c42\u548c\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u7684\u7279\u70b9\u53ca\u5176\u5185\u6838\u5b9e\u73b0\u7ec6\u8282\u3002\u5e76\u7ed3\u5408\u539f\u59cb\u5957\u63a5\u5b57\u7684\u5b9e\u9645\u5e94\u7528\uff0c\u8bf4\u660e\u5404\u7c7b\u578b\u539f\u59cb\u5957\u63a5\u5b57\u7684\u9002\u5e94\u8303\u56f4\uff0c\u4ee5\u53ca\u5728\u5b9e\u9645\u4f7f\u7528\u65f6\u9700\u8981\u6ce8\u610f\u7684\u95ee\u9898\u3002 <\/span><\/span><\/span><\/span> \u4e00\u3001\u539f\u59cb\u5957\u63a5\u5b57\u6982\u8ff0<\/span><\/span><\/span> <\/span><\/span><\/span>\n<\/p>\n

\n\t<\/a><\/a>\u534f\u8bae\u6808\u7684\u539f\u59cb\u5957\u63a5\u5b57\u4ece\u5b9e\u73b0\u4e0a\u53ef\u4ee5\u5206\u4e3a\u201c\u94fe\u8def\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u201d\u548c\u201c\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u201d\u4e24\u5927\u7c7b\u3002\u672c\u8282\u4e3b\u8981\u63cf\u8ff0\u5404\u81ea\u7684\u7279\u70b9\u53ca\u5176\u9002\u7528\u8303\u56f4\u3002<\/span><\/span><\/span><\/span><\/span>\n<\/p>\n

\n\t\u94fe\u8def\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u53ef\u4ee5\u76f4\u63a5\u7528\u4e8e\u63a5\u6536\u548c\u53d1\u9001\u94fe\u8def\u5c42\u7684<\/span>MAC<\/span><\/span><\/span><\/span><\/span>\u5e27\uff0c\u5728\u53d1\u9001\u65f6\u9700\u8981\u7531\u8c03\u7528\u8005\u81ea\u884c\u6784\u9020\u548c\u5c01\u88c5<\/span>MAC<\/span><\/span><\/span><\/span><\/span>\u9996\u90e8\u3002\u800c\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u53ef\u4ee5\u76f4\u63a5\u7528\u4e8e\u63a5\u6536\u548c\u53d1\u9001<\/span>IP<\/span><\/span><\/span><\/span><\/span>\u5c42\u7684\u62a5\u6587\u6570\u636e\uff0c\u5728\u53d1\u9001\u65f6\u9700\u8981\u81ea\u884c\u6784\u9020<\/span>IP<\/span><\/span><\/span><\/span><\/span>\u62a5\u6587\u5934\uff08\u53d6\u51b3\u662f\u5426\u8bbe\u7f6e<\/span>IP_HDRINCL<\/span><\/span><\/span><\/span><\/span>\u9009\u9879\uff09\u3002<\/span><\/span><\/span><\/span><\/span>\n<\/p>\n

<\/span><\/span> <\/p>\n

\n\t<\/span><\/span><\/span>\n<\/p>\n

\n\t1.1  <\/span><\/span><\/span><\/span>\u94fe\u8def\u5c42\u539f\u59cb\u5957\u63a5\u5b57<\/span><\/span><\/span> <\/span><\/span><\/span>\n<\/p>\n

\n\t\u94fe\u8def\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u8c03\u7528<\/span>socket()<\/span><\/span><\/span>\u51fd\u6570\u521b\u5efa\u3002\u7b2c\u4e00\u4e2a\u53c2\u6570\u6307\u5b9a\u534f\u8bae\u65cf\u7c7b\u578b\u4e3a<\/span><\/a><\/a>PF_PACKET<\/span><\/span><\/span><\/span><\/span><\/span><\/span>\uff0c\u7b2c\u4e8c\u4e2a\u53c2\u6570<\/span>type<\/span><\/span><\/span>\u53ef\u4ee5\u8bbe\u7f6e\u4e3a<\/span>SOCK_RAW<\/span><\/span><\/span>\u6216<\/span>SOCK_DGRAM<\/span><\/span><\/span>\uff0c\u7b2c\u4e09\u4e2a\u53c2\u6570\u662f\u534f\u8bae\u7c7b\u578b\uff08\u8be5\u53c2\u6570\u53ea\u5bf9\u62a5\u6587\u63a5\u6536\u6709\u610f\u4e49\uff09\u3002\u534f\u8bae\u7c7b\u578b<\/span>protocol<\/span><\/span><\/span>\u4e0d\u540c\u53d6\u503c\u7684\u610f\u4e49\u5177\u4f53\u89c1\u8868<\/span>1<\/span><\/span><\/span>\u6240\u793a\uff1a<\/span><\/span><\/span><\/a><\/span><\/span>\n<\/p>\n

<\/a> <\/p>\n

\n
\n
    \n
  1. \n\t\t\t\tsocket(<\/span>PF_PACKET,<\/span> type,<\/span> htons(<\/span>protocol)<\/span>)<\/span><\/span>\n\t\t\t<\/li>\n<\/ol><\/div>\n<\/div>\n

    \n\t       <\/span><\/span><\/span><\/span>\n<\/p>\n

    \n\ta)       <\/span><\/span><\/span>\u53c2\u6570<\/span>type<\/span><\/span><\/span>\u8bbe\u7f6e\u4e3a<\/span><\/a><\/a>SOCK_RAW<\/span><\/span><\/span><\/span><\/span><\/span><\/span>\u65f6\uff0c\u5957\u63a5\u5b57\u63a5\u6536\u548c\u53d1\u9001\u7684\u6570\u636e\u90fd\u662f\u4ece<\/span>MAC<\/span><\/span><\/span>\u9996\u90e8\u5f00\u59cb\u7684\u3002\u5728\u53d1\u9001\u65f6\u9700\u8981\u7531\u8c03\u7528\u8005\u4ece<\/span>MAC<\/span><\/span><\/span>\u9996\u90e8\u5f00\u59cb\u6784\u9020\u548c\u5c01\u88c5\u62a5\u6587\u6570\u636e\u3002<\/span>type<\/span><\/span><\/span>\u8bbe\u7f6e\u4e3a<\/span>SOCK_RAW<\/span><\/span><\/span>\u7684\u60c5\u51b5\u5e94\u7528\u662f\u6bd4\u8f83\u591a\u7684\uff0c\u56e0\u4e3a\u67d0\u4e9b\u9879\u76ee\u4f1a\u4f7f\u7528\u5230\u81ea\u5b9a\u4e49\u7684\u4e8c\u5c42\u62a5\u6587\u7c7b\u578b\u3002<\/span><\/span><\/span><\/span><\/span><\/span>\n<\/p>\n

    \n
    \n
      \n
    1. \n\t\t\t\tsocket(<\/span>PF_PACKET,<\/span> SOCK_RAW,<\/span> htons(<\/span>protocol)<\/span>)<\/span><\/span>\n\t\t\t<\/li>\n<\/ol><\/div>\n<\/div>\n

      \n\t\"1\"<\/a>\n<\/p>\n

      \n\tb)      <\/span><\/span><\/span>\u53c2\u6570<\/span>type<\/span><\/span><\/span>\u8bbe\u7f6e\u4e3a<\/span><\/a><\/a>SOCK_DGRAM<\/span><\/span><\/span><\/span><\/span><\/span><\/span>\u65f6\uff0c\u5957\u63a5\u5b57\u63a5\u6536\u5230\u7684\u6570\u636e\u62a5\u6587\u4f1a\u5c06<\/span>MAC<\/span><\/span><\/span>\u9996\u90e8\u53bb\u6389\u3002\u540c\u65f6\u5728\u53d1\u9001\u65f6\u4e5f\u4e0d\u9700\u8981\u518d\u624b\u52a8\u6784\u9020<\/span>MAC<\/span><\/span><\/span>\u9996\u90e8\uff0c\u53ea\u9700\u8981\u4ece<\/span>IP<\/span><\/span><\/span>\u9996\u90e8\uff08\u6216<\/span>ARP<\/span><\/span><\/span>\u9996\u90e8\uff0c\u53d6\u51b3\u4e8e\u5c01\u88c5\u7684\u62a5\u6587\u7c7b\u578b\uff09\u5f00\u59cb\u6784\u9020\u5373\u53ef\uff0c\u800c<\/span>MAC<\/span><\/span><\/span>\u9996\u90e8\u7684\u586b\u5145\u7531\u5185\u6838\u5b9e\u73b0\u7684\u3002\u82e5\u5bf9\u4e8e<\/span>MAC<\/span><\/span><\/span>\u9996\u90e8\u4e0d\u5173\u5fc3\u7684\u573a\u666f\uff0c\u53ef\u4ee5\u4f7f\u7528\u8fd9\u79cd\u7c7b\u578b\uff0c\u8fd9\u79cd\u7528\u6cd5\u7528\u5f97\u6bd4\u8f83\u5c11\u3002<\/span><\/span><\/span><\/span><\/span><\/span>\n<\/p>\n

      \n
      \n
        \n
      1. \n\t\t\t\tsocket(<\/span>PF_PACKET,<\/span> SOCK_DGRAM,<\/span> htons(<\/span>protocol)<\/span>)<\/span><\/span>\n\t\t\t<\/li>\n<\/ol><\/div>\n<\/div>\n

        \n\t      \"1\"<\/a><\/span><\/span><\/span>\n<\/p>\n

        \n\t<\/span><\/span><\/span> \n<\/p>\n

        \n\t<\/span><\/span><\/span>\n<\/p>\n

        \n\t<\/span><\/span><\/span>\n<\/p>\n

        \n\t\u8868<\/span><\/span><\/span>1  <\/span>protocol<\/span><\/span><\/span>\u4e0d\u540c\u53d6\u503c<\/span><\/span><\/span> <\/span><\/span><\/span>\n<\/p>\n

        <\/span> <\/p>\n

        \n\t\n<\/p>\n\n\n\n\n\n\n\n\n\n\n
        \n\t\t\t\t <\/p>\n

        \n\t\t\t\t\tprotocol <\/span><\/b><\/span><\/span>\n\t\t\t\t<\/p>\n

        <\/strong>\n\t\t\t<\/td>\n

        		\n

        \n\t\t\t\t\t\u503c<\/span><\/b><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n

        		\n

        \n\t\t\t\t\t\u4f5c\u7528<\/span><\/b><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n<\/tr>\n

        \n

        \n\t\t\t\t\tETH_P_ALL <\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n

        		\n

        \n\t\t\t\t\t 0x0003 <\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n

        		\n

        \n\t\t\t\t\t\u62a5\u6536\u672c\u673a\u6536\u5230\u7684\u6240\u6709\u4e8c\u5c42\u62a5\u6587<\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n<\/tr>\n

        \n

        \n\t\t\t\t\tETH_P_IP<\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n

        		\n

        \n\t\t\t\t\t0x0800<\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n

        		\n

        \n\t\t\t\t\t\u62a5\u6536\u672c\u673a\u6536\u5230\u7684\u6240\u6709IP\u62a5\u6587<\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n<\/tr>\n

        \n

        \n\t\t\t\t\tETH_P_ARP <\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n

        		\n

        \n\t\t\t\t\t0x0806<\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n

        		\n

        \n\t\t\t\t\t\u62a5\u6536\u672c\u673a\u6536\u5230\u7684\u6240\u6709ARP\u62a5\u6587<\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n<\/tr>\n

        \n

        \n\t\t\t\t\tETH_P_RARP<\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n

        		\n

        \n\t\t\t\t\t0x8035<\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n

        		\n

        \n\t\t\t\t\t\u62a5\u6536\u672c\u673a\u6536\u5230\u7684\u6240\u6709RARP\u62a5\u6587<\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n<\/tr>\n

        \n

        \n\t\t\t\t\t\u81ea\u5b9a\u4e49\u534f\u8bae<\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n

        		\n

        \n\t\t\t\t\t\u6bd4\u59820x0810<\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n

        		\n

        \n\t\t\t\t\t\u62a5\u6536\u672c\u673a\u6536\u5230\u7684\u6240\u6709\u7c7b\u578b\u4e3a0x0810\u7684\u4e8c\u5c42\u62a5\u6587<\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n<\/tr>\n

        \n

        \n\t\t\t\t\t\u4e0d\u6307\u5b9a<\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n

        		\n

        \n\t\t\t\t\t0<\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n

        		\n

        \n\t\t\t\t\t\u4e0d\u80fd\u7528\u4e8e\u63a5\u6536\uff0c\u53ea\u7528\u4e8e\u53d1\u9001<\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n<\/tr>\n

        \n

        \n\t\t\t\t\t\u2026\u2026 <\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n

        		\n

        \n\t\t\t\t\t\u2026\u2026 <\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n

        		\n

        \n\t\t\t\t\t\u2026\u2026<\/span><\/span><\/span>\n\t\t\t\t<\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

        <\/span><\/span> <\/p>\n

        \n\t\u8868<\/span>1<\/span><\/span><\/span>\u4e2d<\/span>protocol<\/span><\/span><\/span>\u7684\u53d6\u503c\u4e2d\u6709\u4e24\u4e2a\u503c\u662f\u6bd4\u8f83\u7279\u6b8a\u7684\u3002\u5f53<\/span>protocol<\/span><\/span><\/span>\u4e3a<\/span>ETH_P_ALL<\/span><\/span><\/span>\u65f6\uff0c\u8868\u793a\u80fd\u591f\u63a5\u6536\u672c\u673a\u6536\u5230\u7684\u6240\u6709\u4e8c\u5c42\u62a5\u6587\uff08\u5305\u62ec<\/span>IP, ARP, <\/span><\/span><\/span>\u81ea\u5b9a\u4e49\u4e8c\u5c42\u62a5\u6587\u7b49\uff09\uff0c\u540c\u65f6\u8fd9\u79cd\u7c7b\u578b\u5957\u63a5\u5b57\u8fd8\u80fd\u591f\u5c06\u5916\u53d1\u7684\u62a5\u6587\u518d\u6536\u56de\u6765\u3002\u5f53<\/span>protocol<\/span><\/span><\/span>\u4e3a<\/span>0<\/span><\/span><\/span>\u65f6\uff0c\u8868\u793a\u8be5\u5957\u63a5\u5b57\u4e0d\u80fd\u7528\u4e8e\u63a5\u6536\u62a5\u6587\uff0c\u53ea\u80fd\u7528\u4e8e\u53d1\u9001\u3002<\/a><\/a>\u5177\u4f53\u7684\u5b9e\u73b0\u7ec6\u8282\u5728<\/span><\/span><\/span>2.2<\/span><\/span><\/span><\/span><\/span>\u8282\u4e2d\u4f1a\u8be6\u7ec6\u4ecb\u7ecd\u3002<\/span><\/span><\/span><\/span><\/span>\n<\/p>\n

        \n\t<\/span><\/span><\/span>\n<\/p>\n

        \n\t \n<\/p>\n

        1.2  <\/span><\/span><\/span><\/span>\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57<\/span><\/span><\/span> <\/span><\/span><\/span> <\/p>\n

        \n\t\u521b\u5efa\u9762\u5411\u8fde\u63a5\u7684<\/span>TCP<\/span><\/span><\/span>\u548c\u521b\u5efa\u9762\u5411\u65e0\u8fde\u63a5\u7684<\/span>UDP<\/span><\/span><\/span>\u5957\u63a5\u5b57\uff0c\u5728\u63a5\u6536\u548c\u53d1\u9001\u65f6\u53ea\u80fd\u64cd\u4f5c\u6570\u636e\u90e8\u5206\uff0c\u800c\u4e0d\u80fd\u5bf9<\/span>IP<\/span><\/span><\/span>\u9996\u90e8\u6216<\/span>TCP<\/span><\/span><\/span>\u548c<\/span>UDP<\/span><\/span><\/span>\u9996\u90e8\u8fdb\u884c\u64cd\u4f5c\u3002\u5982\u679c\u60f3\u8981\u64cd\u4f5c<\/span>IP<\/span><\/span><\/span>\u9996\u90e8\u6216\u4f20\u8f93\u5c42\u534f\u8bae\u9996\u90e8\uff0c\u5c31\u9700\u8981\u8c03\u7528\u5982\u4e0b<\/span>socket()<\/span><\/span><\/span>\u51fd\u6570\u521b\u5efa\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u3002\u7b2c\u4e00\u4e2a\u53c2\u6570\u6307\u5b9a\u534f\u8bae\u65cf\u7684\u7c7b\u578b\u4e3a<\/span>PF_INET<\/span><\/span><\/span>\uff0c\u7b2c\u4e8c\u4e2a\u53c2\u6570\u4e3a<\/span>SOCK_RAW<\/span><\/span><\/span>\uff0c\u7b2c\u4e09\u4e2a\u53c2\u6570<\/span>protocol<\/span><\/span><\/span>\u4e3a\u534f\u8bae\u7c7b\u578b\uff08\u4e0d\u540c\u53d6\u503c\u7684\u610f\u4e49\u89c1\u8868<\/span>2<\/span><\/span><\/span>\uff09\u3002\u4ea7\u54c1\u7ebf\u6709\u4f7f\u7528<\/span>OSPF<\/span><\/span><\/span>\u548c<\/span>RSVP<\/span><\/span><\/span>\u7b49\u534f\u8bae\uff0c\u9700\u8981\u4f7f\u7528\u8fd9\u79cd\u7c7b\u578b\u7684\u5957\u63a5\u5b57\u3002<\/span><\/span><\/span><\/a><\/span><\/span>\n<\/p>\n

        <\/a> <\/p>\n

        \n\t<\/a> <\/p>\n
        \n
          \n
        1. \n\t\t\t\tsocktet(<\/span>PF_INET,<\/span> SOCK_RAW,<\/span> protocol)<\/span><\/span>\n\t\t\t<\/li>\n<\/ol><\/div>\n

              <\/span><\/span><\/span><\/span>\n<\/div>\n

          \n\ta)       <\/span><\/span><\/span>\u63a5\u6536\u62a5\u6587<\/span><\/span><\/span>\n<\/p>\n

          \n\t\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u63a5\u6536\u5230\u7684\u62a5\u6587\u6570\u636e\u662f\u4ece<\/span>IP<\/span><\/span><\/span>\u9996\u90e8\u5f00\u59cb\u7684\uff0c\u5373\u63a5\u6536\u5230\u7684\u6570\u636e\u5305\u542b\u4e86<\/span>IP<\/span><\/span><\/span>\u9996\u90e8<\/span>, TCP\/UDP\/ICMP<\/span><\/span><\/span>\u7b49\u9996\u90e8<\/span>, <\/span><\/span><\/span>\u4ee5\u53ca\u6570\u636e\u90e8\u5206\u3002<\/span><\/span><\/span>\n<\/p>\n

          \n\t<\/span><\/span><\/span>\n<\/p>\n

          \n\t      \"1\"<\/a> <\/span><\/span><\/span><\/span>\n<\/p>\n

          \n\tb)      <\/span><\/span><\/span>\u53d1\u9001\u62a5\u6587<\/span><\/span><\/span>\n<\/p>\n

          \n\t\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u53d1\u9001\u7684\u62a5\u6587\u6570\u636e\uff0c\u5728\u9ed8\u8ba4\u60c5\u51b5\u4e0b\u662f\u4ece<\/span>IP<\/span><\/span><\/span>\u9996\u90e8\u4e4b\u540e\u5f00\u59cb\u7684\uff0c\u5373\u9700\u8981\u7531\u8c03\u7528\u8005\u81ea\u884c\u6784\u9020\u548c\u5c01\u88c5<\/span>TCP\/UDP<\/span><\/span><\/span>\u7b49\u534f\u8bae\u9996\u90e8\u3002<\/span><\/span><\/span>\n<\/p>\n

          \n\t\"1\"<\/a> <\/span><\/span><\/span>\n<\/p>\n

          \n\t<\/span><\/span><\/span>\n<\/p>\n

          \n\t\u8fd9\u79cd\u5957\u63a5\u5b57\u4e5f\u63d0\u4f9b\u4e86\u53d1\u9001\u65f6\u4ece<\/span>IP<\/span><\/span><\/span>\u9996\u90e8\u5f00\u59cb\u6784\u9020\u6570\u636e\u7684\u529f\u80fd\uff0c\u901a\u8fc7<\/span>setsockopt()<\/span><\/span><\/span>\u7ed9\u5957\u63a5\u5b57\u8bbe\u7f6e\u4e0a<\/span>IP_HDRINCL<\/span><\/span><\/span>\u9009\u9879\uff0c\u5c31\u9700\u8981\u5728\u53d1\u9001\u65f6\u81ea\u884c\u6784\u9020<\/span>IP<\/span><\/span><\/span>\u9996\u90e8\u3002<\/span><\/span><\/span>\n<\/p>\n

          \n\t\n<\/p>\n\n\n\n
          \n
          \n

          \n\t\t\t\t\t\t   <\/span>\n\t\t\t\t\t<\/p>\n

          \n
          \n
            \n
          1. \n\t\t\t\t\t\t\t\t\tint<\/span> val =<\/span> 1;<\/span>
            \n<\/span>\n\t\t\t\t\t\t\t\t<\/li>\n
          2. \n\t\t\t\t\t\t\t\t\tsetsockopt (<\/span>sockfd,<\/span> IPPROTO_IP,<\/span> IP_HDRINCL,<\/span> &<\/span>val,<\/span> sizeof(<\/span>val)<\/span>)<\/span>;<\/span>\n\t\t\t\t\t\t\t\t<\/li>\n<\/ol><\/div>\n

            <\/span>\n\t\t\t\t\t<\/div>\n<\/p><\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

            \n\t\u8868<\/span><\/span><\/span>2  <\/span>protocol<\/span><\/span><\/span>\u4e0d\u540c\u53d6<\/span><\/span><\/span><\/span><\/span><\/span>\n<\/p>\n

            \n\n\n\n\n\n\n\n\n\n\n
            \n\t\t\t\t\t <\/p>\n

            \n\t\t\t\t\t\tprotocol <\/span><\/b><\/span><\/span>\n\t\t\t\t\t<\/p>\n

            <\/strong>\n\t\t\t\t<\/td>\n

            		\n

            \n\t\t\t\t\t\t\u503c<\/span><\/b><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n

            		\n

            \n\t\t\t\t\t\t\u4f5c\u7528<\/span><\/b><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n<\/tr>\n

            \n

            \n\t\t\t\t\t\tIPPROTO_TCP <\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n

            		\n

            \n\t\t\t\t\t\t6<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n

            		\n

            \n\t\t\t\t\t\t\u62a5\u6536TCP\u7c7b\u578b\u7684\u62a5\u6587<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n<\/tr>\n

            \n

            \n\t\t\t\t\t\tIPPROTO_UDP<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n

            		\n

            \n\t\t\t\t\t\t17<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n

            		\n

            \n\t\t\t\t\t\t\u62a5\u6536UDP\u7c7b\u578b\u7684\u62a5\u6587<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n<\/tr>\n

            \n

            \n\t\t\t\t\t\tIPPROTO_ICMP <\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n

            		\n

            \n\t\t\t\t\t\t1<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n

            		\n

            \n\t\t\t\t\t\t\u62a5\u6536ICMP\u7c7b\u578b\u7684\u62a5\u6587<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n<\/tr>\n

            \n

            \n\t\t\t\t\t\tIPPROTO_IGMP<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n

            		\n

            \n\t\t\t\t\t\t2<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n

            		\n

            \n\t\t\t\t\t\t\u62a5\u6536IGMP\u7c7b\u578b\u7684\u62a5\u6587<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n<\/tr>\n

            \n

            \n\t\t\t\t\t\tIPPROTO_RAW<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n

            		\n

            \n\t\t\t\t\t\t255<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n

            		\n

            \n\t\t\t\t\t\t\u4e0d\u80fd\u7528\u4e8e\u63a5\u6536\uff0c\u53ea\u7528\u4e8e\u53d1\u9001\uff08\u9700\u8981\u6784\u9020IP\u9996\u90e8\uff09<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n<\/tr>\n

            \n

            \n\t\t\t\t\t\tOSPF<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n

            		\n

            \n\t\t\t\t\t\t89<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n

            		\n

            \n\t\t\t\t\t\t\u63a5\u6536\u534f\u8bae\u53f7\u4e3a89\u7684\u62a5\u6587<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n<\/tr>\n

            \n

            \n\t\t\t\t\t\t\u2026\u2026 <\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n

            		\n

            \n\t\t\t\t\t\t\u2026\u2026 <\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n

            		\n

            \n\t\t\t\t\t\t\u2026\u2026<\/span><\/span><\/span>\n\t\t\t\t\t<\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

            \n\t\u8868<\/span>2<\/span><\/span><\/span>\u4e2d<\/span>protocol<\/span><\/span><\/span>\u53d6\u503c\u4e3a<\/span>IPPROTO_RAW<\/span><\/span><\/span>\u662f\u6bd4\u8f83\u7279\u6b8a\u7684\uff0c\u8868\u793a\u5957\u63a5\u5b57\u4e0d\u80fd\u7528\u4e8e\u63a5\u6536\uff0c\u53ea\u80fd\u7528\u4e8e\u53d1\u9001\uff08\u4e14\u53d1\u9001\u65f6\u9700\u8981\u4ece<\/span>IP<\/span><\/span><\/span>\u9996\u90e8\u5f00\u59cb\u6784\u9020\u62a5\u6587\uff09\u3002\u5177\u4f53\u7684\u5b9e\u73b0\u7ec6\u8282\u5728<\/span>2.3<\/span><\/span><\/span>\u8282\u4e2d\u4f1a\u8be6\u7ec6\u4ecb\u7ecd\u3002<\/span><\/span><\/span>\n<\/p>\n

            \n\t<\/span><\/span><\/span>\n<\/p>\n

            \n\t \n<\/p>\n

            \u4e8c\u3001\u539f\u59cb\u5957\u63a5\u5b57\u5b9e\u73b0<\/span><\/span><\/span> <\/span><\/span><\/span> <\/p>\n

            \n\t\u672c\u8282\u4e3b\u8981\u9996\u5148\u4ecb\u7ecd\u94fe\u8def\u5c42\u548c\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u62a5\u6587\u7684\u6536\u53d1\u603b\u4f53\u6d41\u7a0b\uff0c\u518d\u5206\u522b\u5bf9\u4e24\u7c7b\u5957\u63a5\u5b57\u7684\u521b\u5efa\u3001\u63a5\u6536\u3001\u53d1\u9001\u7b49\u5177\u4f53\u5b9e\u73b0\u7ec6\u8282\u8fdb\u884c\u4ecb\u7ecd\u3002<\/span><\/span><\/span>\n<\/p>\n

            \n\t<\/span><\/span><\/span>\n<\/p>\n

            \n\t \n<\/p>\n

            2.1  <\/span><\/span><\/span><\/span>\u539f\u59cb\u5957\u63a5\u5b57\u62a5\u6587\u6536\u53d1\u6d41\u7a0b<\/span><\/span><\/span> <\/span><\/span><\/span> <\/p>\n

            \n\t<\/span><\/span><\/span>\"1\"<\/a> <\/span><\/span><\/span>\n<\/p>\n

            \n\t\u56fe<\/span><\/span><\/span>1  <\/span><\/span><\/span><\/span>\u539f\u59cb\u5957\u63a5\u5b57\u6536\u53d1\u6d41\u7a0b<\/span><\/span><\/span>\n<\/p>\n

            \n\t<\/span><\/span><\/span>\n<\/p>\n

            \n\t \n<\/p>\n

            \n\t\u5982\u4e0a\u56fe<\/span>1<\/span><\/span><\/span>\u6240\u793a\u4e3a\u94fe\u8def\u5c42\u548c\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u7684\u6536\u53d1\u603b\u4f53\u6d41\u7a0b\u3002\u7f51\u5361\u9a71\u52a8\u6536\u5230\u62a5\u6587\u540e\u5728\u8f6f\u4e2d\u65ad\u4e0a\u4e0b\u6587\u4e2d\u7531<\/span>netif_receive_skb()<\/span><\/span><\/span>\u5904\u7406\uff0c\u5339\u914d\u662f\u5426\u6709\u6ce8\u518c\u7684\u94fe\u8def\u5c42\u539f\u59cb\u5957\u63a5\u5b57\uff0c\u82e5\u5339\u914d\u4e0a\u5c31\u901a\u8fc7<\/span>skb_clone()<\/span><\/span><\/span>\u6765\u514b\u9686\u62a5\u6587\uff0c\u5e76\u5c06\u62a5\u6587\u4ea4\u7ed9\u76f8\u5e94\u7684\u539f\u59cb\u5957\u63a5\u5b57\u3002\u5bf9\u4e8e<\/span>IP<\/span><\/span><\/span>\u62a5\u6587\uff0c\u5728\u534f\u8bae\u6808\u7684<\/span>ip_local_deliver_finish()<\/span><\/span><\/span>\u51fd\u6570\u4e2d\u4f1a\u5339\u914d\u662f\u5426\u6709\u6ce8\u518c\u7684\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\uff0c\u82e5\u5339\u914d\u4e0a\u5c31\u901a\u8fc7<\/span>skb_clone()<\/span><\/span><\/span>\u514b\u9686\u62a5\u6587\u5e76\u4ea4\u7ed9\u76f8\u5e94\u7684\u539f\u59cb\u5957\u63a5\u5b57\u6765\u5904\u7406\u3002<\/span><\/span><\/span>\n<\/p>\n

            \n\t\u6ce8\u610f\uff1a\u8fd9\u91cc\u53ea\u662f\u5c06\u62a5\u6587\u514b\u9686\u4e00\u4efd\u4ea4\u7ed9\u539f\u59cb\u5957\u63a5\u5b57\uff0c\u800c\u8be5\u62a5\u6587\u8fd8\u662f\u4f1a\u7ee7\u7eed\u8d70\u540e\u7eed\u7684\u534f\u8bae\u6808\u5904\u7406\u6d41\u7a0b\u3002<\/span><\/span><\/span> <\/span><\/span><\/span>\n<\/p>\n

            \n\t      <\/span><\/span><\/span><\/span>\u94fe\u8def\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u7684\u53d1\u9001\uff0c\u76f4\u63a5\u7531\u5957\u63a5\u5b57\u5c42\u8c03\u7528<\/span>packet_sendmsg()<\/span><\/span><\/span>\u51fd\u6570\uff0c\u6700\u7ec8\u518d\u8c03\u7528\u7f51\u5361\u9a71\u52a8\u7684\u53d1\u9001\u51fd\u6570\u3002\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u7684\u53d1\u9001\u5b9e\u73b0\u8981\u76f8\u5bf9\u590d\u6742\u4e00\u4e9b\uff0c\u7531\u5957\u63a5\u5b57\u5c42\u8c03\u7528<\/span>inet_sendmsg()->raw_sendmsg()<\/span><\/span><\/span>\uff0c\u518d\u7ecf\u8fc7\u8def\u7531\u548c\u90bb\u5c45\u5b50\u7cfb\u7edf\u7684\u5904\u7406\u540e\uff0c\u6700\u7ec8\u8c03\u7528\u7f51\u5361\u9a71\u52a8\u7684\u53d1\u9001\u51fd\u6570\u3002\u82e5\u6ce8\u518c\u4e86<\/span>ETH_P_ALL<\/span><\/span><\/span>\u7c7b\u578b\u5957\u63a5\u5b57\uff0c\u8fd8\u9700\u8981\u5c06\u5916\u53d1\u62a5\u6587\u518d\u6536\u56de\u53bb\u3002<\/span><\/span><\/span>\n<\/p>\n

            \n\t<\/span><\/span><\/span>\n<\/p>\n

            \n\t \n<\/p>\n

            2.2  <\/span><\/span><\/span><\/span>\u94fe\u8def\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u7684\u5b9e\u73b0<\/span><\/span><\/span> <\/span><\/span><\/span>2.2.1  <\/span><\/span><\/span><\/span>\u5957\u63a5\u5b57\u521b\u5efa<\/span><\/span><\/span> <\/span><\/span><\/span> <\/p>\n

            \n\t<\/a><\/a>\u8c03\u7528<\/span>socket()<\/span><\/span><\/span><\/span><\/span>\u51fd\u6570\u521b\u5efa\u5957\u63a5\u5b57\u7684\u6d41\u7a0b\u5982\u4e0b\uff0c\u94fe\u8def\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u6700\u7ec8\u7531<\/span>packet_create()<\/span><\/span><\/span><\/span><\/span>\u521b\u5efa<\/span><\/span><\/span><\/span><\/span>\u3002<\/span><\/span><\/span>\n<\/p>\n

            \n\tsys_socket()->sock_create()->__sock_create()->packet_create()<\/span><\/span><\/span>\n<\/p>\n

            \n\t<\/span><\/span><\/span>\n<\/p>\n

            \n\t    \u5f53<\/span>socket()<\/span><\/span><\/span>\u51fd\u6570\u7684\u7b2c\u4e09\u4e2a\u53c2\u6570<\/span>protocol<\/span><\/span><\/span>\u4e3a\u975e\u96f6\u7684\u60c5\u51b5\u4e0b\uff0c\u4f1a\u8c03\u7528<\/span>dev_add_pack()<\/span><\/span><\/span>\u5c06\u94fe\u8def\u5c42\u5957\u63a5\u5b57<\/span>packet_sock<\/span><\/span><\/span>\u7684<\/span>packet_type<\/span><\/span><\/span>\u7ed3\u6784\u94fe\u5230<\/span>ptype_all<\/span><\/span><\/span>\u94fe\u8868\u6216<\/span>ptype_base<\/span><\/span><\/span>\u94fe\u8868\u4e2d\u3002<\/span><\/span><\/span>    <\/span><\/span><\/span><\/span>\n<\/p>\n

            \n
            \n
              \n
            1. \n\t\t\t\tvoid dev_add_pack(<\/span>struct packet_type *<\/span>pt)<\/span>
              \n<\/span>\n\t\t\t<\/li>\n
            2. \n\t\t\t\t{<\/span> \n\t\t\t<\/li>\n
            3. \n\t\t\t\t        \u2026\u2026 \n\t\t\t<\/li>\n
            4. \n\t\t\t\t        if<\/span> (<\/span>pt–<\/span>><\/span>type =<\/span>=<\/span> htons(<\/span>ETH_P_ALL)<\/span>)<\/span> {<\/span> \n\t\t\t<\/li>\n
            5. \n\t\t\t\t                netdev_nit+<\/span>+<\/span>;<\/span> \n\t\t\t<\/li>\n
            6. \n\t\t\t\t                list_add_rcu(<\/span>&<\/span>pt–<\/span>><\/span>list,<\/span> &<\/span>ptype_all)<\/span>;<\/span> \n\t\t\t<\/li>\n
            7. \n\t\t\t\t        }<\/span> else<\/span> {<\/span> \n\t\t\t<\/li>\n
            8. \n\t\t\t\t                hash =<\/span> ntohs(<\/span>pt–<\/span>><\/span>type)<\/span> &<\/span> 15;<\/span> \n\t\t\t<\/li>\n
            9. \n\t\t\t\t                list_add_rcu(<\/span>&<\/span>pt–<\/span>><\/span>list,<\/span> &<\/span>ptype_base[<\/span>hash]<\/span>)<\/span>;<\/span> \n\t\t\t<\/li>\n
            10. \n\t\t\t\t        }<\/span> \n\t\t\t<\/li>\n
            11. \n\t\t\t\t        \u2026\u2026 \n\t\t\t<\/li>\n
            12. \n\t\t\t\t}<\/span>\n\t\t\t<\/li>\n<\/ol><\/div>\n<\/div>\n

              \n\t    \u5f53<\/span>protocol<\/span><\/span><\/span>\u4e3a<\/span>ETH_P_ALL<\/span><\/span><\/span>\u65f6\uff0c\u4f1a\u5c06\u5957\u63a5\u5b57\u52a0\u5165\u5230<\/span>ptype_all<\/span><\/span><\/span>\u94fe\u8868\u4e2d\u3002\u5982\u56fe<\/span>2<\/span><\/span><\/span>\u6240\u793a\uff0c\u8fd9\u91cc\u521b\u5efa\u4e86\u4e24\u4e2a\u94fe\u8def\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u3002<\/span><\/span><\/span>\n<\/p>\n

              \n\t<\/span><\/span><\/span>\n<\/p>\n

              \n\t\"2\"<\/a> <\/span><\/span><\/span>\n<\/p>\n

              \n\t\u56fe<\/span><\/span><\/span>2  <\/span>ptype_all<\/span><\/span><\/span>\u94fe\u8868<\/span><\/span><\/span> <\/span><\/span><\/span>\n<\/p>\n

              \n\t\u5f53<\/span>protocol<\/span><\/span><\/span>\u4e3a\u5176\u5b83\u975e<\/span>0<\/span><\/span><\/span>\u503c\u65f6\uff0c\u4f1a\u5c06\u5957\u63a5\u5b57\u52a0\u5165\u5230<\/span>ptype_base<\/span><\/span><\/span>\u94fe\u8868\u4e2d\u3002\u5982\u56fe<\/span>3<\/span><\/span><\/span>\u6240\u793a\uff0c\u534f\u8bae\u6808\u672c\u8eab\u4e5f\u9700\u8981\u6ce8\u518c<\/span>packet_type<\/span><\/span><\/span>\u7ed3\u6784\uff0c\u56fe\u4e2d\u6d45\u8272\u7684\u4e24\u4e2a<\/span>packet_type<\/span><\/span><\/span>\u7ed3\u6784\u5206\u522b\u662f<\/span>IP<\/span><\/span><\/span>\u534f\u8bae\u548c<\/span>ARP<\/span><\/span><\/span>\u534f\u8bae\u6ce8\u518c\u7684\uff0c\u5176\u5904\u7406\u51fd\u6570\u5206\u522b\u4e3a<\/span>ip_rcv()<\/span><\/span><\/span>\u548c<\/span>arp_rcv()<\/span><\/span><\/span>\u3002\u56fe\u4e2d\u53e6\u5916<\/span>3<\/span><\/span><\/span>\u4e2a\u6df1\u8272\u7684<\/span>packet_type<\/span><\/span><\/span>\u7ed3\u6784\u5219\u662f\u94fe\u8def\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u6ce8\u518c\u7684\uff0c\u5206\u522b\u7528\u4e8e\u63a5\u6536\u7c7b\u578b\u4e3a<\/span>ETH_P_IP<\/span><\/span><\/span>\u3001<\/span>ETH_P_ARP<\/span><\/span><\/span>\u548c<\/span>0x0810<\/span><\/span><\/span>\u7c7b\u578b\u7684\u62a5\u6587\u3002<\/span><\/span><\/span>\n<\/p>\n

              \n\t<\/span><\/span><\/span>\n<\/p>\n

              \n\t\"3\"<\/a> <\/span><\/span><\/span>\n<\/p>\n

              \n\t\u56fe<\/span><\/span><\/span>3  <\/span>ptype_base<\/span><\/span><\/span>\u94fe\u8868<\/span><\/span><\/span> <\/span><\/span><\/span>\n<\/p>\n

              \n\t<\/span><\/span><\/span>\n<\/p>\n

              \n\t \n<\/p>\n

              2.2.2  <\/span><\/span><\/span><\/span>\u62a5\u6587\u63a5\u6536<\/span><\/span><\/span> <\/span><\/span><\/span> <\/p>\n

              \n\t\u7f51\u5361\u9a71\u52a8\u7a0b\u5e8f\u63a5\u6536\u5230\u62a5\u6587\u540e\uff0c\u5728\u8f6f\u4e2d\u65ad\u4e0a\u4e0b\u6587\u7531<\/span>netif_receive_skb()<\/span><\/span><\/span>\u5904\u7406\u3002\u9996\u5148\u4f1a\u9010\u4e2a\u904d\u5386<\/span>ptype_all<\/span><\/span><\/span>\u94fe\u8868\u4e2d\u7684<\/span>packet_type<\/span><\/span><\/span>\u7ed3\u6784\uff0c\u82e5\u6ee1\u8db3\u6761\u4ef6\u201c<\/span>(!ptype->dev || ptype->dev == skb->dev)<\/span><\/span><\/span>\u201d\uff0c\u5373\u5957\u63a5\u5b57\u672a\u7ed1\u5b9a\u6216\u8005\u5957\u63a5\u5b57\u7ed1\u5b9a\u7f51\u53e3\u4e0e<\/span>skb<\/span><\/span><\/span>\u6240\u5728\u7f51\u53e3\u5339\u914d\uff0c\u5c31\u589e\u52a0\u62a5\u6587\u5f15\u7528\u8ba1\u6570\u5e76\u4ea4\u7ed9<\/span>packet_rcv()<\/span><\/span><\/span>\u51fd\u6570\u5904\u7406\uff08\u82e5\u4f7f\u7528<\/span>PACKET_MMAP<\/span><\/span><\/span>\u6536\u5305\u65b9\u5f0f\u5219\u7531<\/span>tpacket_rcv()<\/span><\/span><\/span>\u51fd\u6570\u5904\u7406\uff09\u3002<\/span><\/span><\/span>\n<\/p>\n

              \n\t\u7f51\u5361\u9a71\u52a8<\/span>->netif_receive_skb()->deliver_skb()->packet_rcv()\/tpacket_rcv()<\/span><\/span><\/span>\n<\/p>\n

              \n\t<\/span><\/span><\/span>\n<\/p>\n

              \n\t    \u4ee5\u975e<\/span>PACKET_MMAP<\/span><\/span><\/span>\u6536\u5305\u65b9\u5f0f\u4e3a\u4f8b\u8fdb\u884c\u8bf4\u660e\uff0c<\/span>packet_rcv()<\/span><\/span><\/span>\u51fd\u6570\u4e2d\u6bd4\u8f83\u91cd\u8981\u7684\u4ee3\u7801\u7247\u6bb5\u5982\u4e0b\u3002\u5f53\u62a5\u6587<\/span>skb<\/span><\/span><\/span>\u5230\u8fbe<\/span>packet_rcv()<\/span><\/span><\/span>\u51fd\u6570\u65f6\uff0c\u5176<\/span>skb->data<\/span><\/span><\/span>\u6240\u6307\u7684\u6570\u636e\u662f\u4e0d\u5305\u542b<\/span>MAC<\/span><\/span><\/span>\u9996\u90e8\u7684\uff0c\u6240\u4ee5\u5bf9\u4e8e<\/span>type<\/span><\/span><\/span>\u4e3a\u975e<\/span>SOCK_DGRAM<\/span><\/span><\/span>\uff08\u5373<\/span>SOCK_RAW<\/span><\/span><\/span>\uff09\u7c7b\u578b\uff0c\u9700\u8981\u5c06<\/span>skb->data<\/span><\/span><\/span>\u6307\u9488\u524d\u79fb\uff0c\u4ee5\u4fbf\u6570\u636e\u90e8\u5206\u53ef\u4ee5\u5305\u542b<\/span>MAC<\/span><\/span><\/span>\u9996\u90e8\u3002\u6700\u540e\u5c06<\/span>skb<\/span><\/span><\/span>\u653e\u5230\u5957\u63a5\u5b57\u7684\u63a5\u6536\u961f\u5217<\/span>sk->sk_receive_queue<\/span><\/span><\/span>\u4e2d\uff0c\u5e76\u5524\u9192\u7528\u6237\u6001\u8fdb\u7a0b\u6765\u8bfb\u53d6\u5957\u63a5\u5b57\u4e2d\u7684\u6570\u636e\u3002<\/span><\/span><\/span><\/span><\/span><\/span>\n<\/p>\n

              \n
              \n
                \n
              1. \n\t\t\t\t\u2026\u2026
                \n<\/span>\n\t\t\t<\/li>\n
              2. \n\t\t\t\tif<\/span> (<\/span>sk–<\/span>><\/span>sk_type !<\/span>=<\/span> SOCK_DGRAM)<\/span> \/<\/span>\/<\/span>\u5373SOCK_RAW\u7c7b\u578b \n\t\t\t<\/li>\n
              3. \n\t\t\t\t        skb_push(<\/span>skb,<\/span> skb–<\/span>><\/span>data –<\/span> skb–<\/span>><\/span>mac.<\/span>raw)<\/span>;<\/span> \n\t\t\t<\/li>\n
              4. \n\t\t\t\t\u2026\u2026 \n\t\t\t<\/li>\n
              5. \n\t\t\t\t__skb_queue_tail(<\/span>&<\/span>sk–<\/span>><\/span>sk_receive_queue,<\/span> skb)<\/span>;<\/span> \n\t\t\t<\/li>\n
              6. \n\t\t\t\tsk–<\/span>><\/span>sk_data_ready(<\/span>sk,<\/span> skb–<\/span>><\/span>len<\/span>)<\/span>;<\/span> \/<\/span>\/<\/span>\u5524\u9192\u8fdb\u7a0b\u8bfb\u53d6\u6570\u636e \n\t\t\t<\/li>\n
              7. \n\t\t\t\t\u2026\u2026\n\t\t\t<\/li>\n<\/ol><\/div>\n<\/div>\n

                \n\tPACKET_MMAP<\/span><\/span><\/span>\u6536\u5305\u65b9\u5f0f\u7684\u5b9e\u73b0\u6709\u6240\u4e0d\u540c\uff0c<\/span>tpacket_rcv()<\/span><\/span><\/span>\u51fd\u6570\u5c06<\/span>skb->data<\/span><\/span><\/span>\u62f7\u8d1d\u5230\u4e0e\u7528\u6237\u6001<\/span>mmap<\/span><\/span><\/span>\u6620\u5c04\u7684\u5171\u4eab\u5185\u5b58\u4e2d\uff0c\u6700\u540e\u5524\u9192\u7528\u6237\u6001\u8fdb\u7a0b\u6765\u8bfb\u53d6\u6570\u636e\u3002\u7531\u4e8e\u62a5\u6587\u7684\u5185\u5bb9\u5df2\u5b58\u653e\u5728\u5185<\/span><\/span><\/span>\u6838\u7a7a\u95f4\u548c\u7528\u6237\u7a7a\u95f4\u5171\u4eab\u7684\u7f13\u51b2\u533a\u4e2d\uff0c\u7528\u6237\u6001\u53ef\u4ee5\u76f4\u63a5\u8bfb\u53d6\u4ee5\u51cf\u5c11\u6570\u636e\u7684\u62f7\u8d1d\uff0c\u6240\u4ee5\u8fd9\u79cd\u65b9\u5f0f\u6548\u7387\u6bd4\u8f83\u9ad8\u3002<\/span><\/span><\/span>\n<\/p>\n

                \n\t<\/span><\/span><\/span>\n<\/p>\n

                \n\t    \u4e0a\u9762\u4ecb\u7ecd\u4e86\u62a5\u6587\u63a5\u6536\u5728\u8f6f\u4e2d\u65ad\u7684\u5904\u7406\u6d41\u7a0b\u3002\u4e0b\u9762\u4ee5\u975e<\/span>PACKET_MMAP<\/span><\/span><\/span>\u6536\u5305\u65b9\u5f0f\u4e3a\u4f8b\uff0c\u4ecb\u7ecd\u7528\u6237\u6001\u8bfb\u53d6\u62a5\u6587\u6570\u636e\u7684\u6d41\u7a0b\u3002\u7528\u6237\u6001<\/span>recvmsg()<\/span><\/span><\/span>\u6700\u7ec8\u8c03\u7528<\/span>skb_recv_datagram()<\/span><\/span><\/span>\uff0c\u5982\u679c\u5957\u63a5\u5b57\u63a5\u6536\u961f\u5217<\/span>sk->sk_receive_queue<\/span><\/span><\/span>\u4e2d\u6709\u62a5\u6587\u5c31\u53d6<\/span>skb<\/span><\/span><\/span>\u5e76\u8fd4\u56de\u3002\u5426\u5219\u8c03\u7528<\/span>wait_for_packet()<\/span><\/span><\/span>\u7b49\u5f85\uff0c\u76f4\u5230\u5185\u6838\u8f6f\u4e2d\u65ad\u6536\u5230\u62a5\u6587\u5e76\u5524\u9192\u7528\u6237\u6001\u8fdb\u7a0b\u3002<\/span><\/span><\/span>\n<\/p>\n

                \n\tsys_recvmsg()->sock_recvmsg()->\u2026->packet_recvmsg()->skb_recv_datagram()<\/span><\/span><\/span>\n<\/p>\n

                \n\t<\/span><\/span><\/span>\n<\/p>\n

                \n\t \n<\/p>\n

                2.2.3  <\/span><\/span><\/span><\/span>\u62a5\u6587\u53d1\u9001<\/span><\/span><\/span> <\/span><\/span><\/span> <\/p>\n

                \n\t\u7528\u6237\u6001\u8c03\u7528<\/span>sendto()<\/span><\/span><\/span>\u6216<\/span>sendmsg()<\/span><\/span><\/span><\/a>\u53d1\u9001\u62a5\u6587\u7684\u5185\u6838\u6001\u5904\u7406\u6d41\u7a0b\u5982\u4e0b<\/span><\/span><\/span><\/span>\uff0c\u7531\u5957\u63a5\u5b57\u5c42\u6700\u7ec8\u4f1a\u8c03\u7528\u5230<\/span>packet_sendmsg()<\/span><\/span><\/span>\u3002<\/span><\/span><\/span>\n<\/p>\n

                \n\tsys_sendto()->sock_sendmsg()->__sock_sendmsg()->packet_sendmsg()->dev_queue_xmit()<\/span><\/span><\/span>\n<\/p>\n

                \n\t<\/span><\/span><\/span>\n<\/p>\n

                \n\t    \u8be5\u51fd\u6570\u6bd4\u8f83\u91cd\u8981\u7684\u51fd\u6570\u7247\u6bb5\u5982\u4e0b\u3002\u9996\u5148\u8fdb\u884c\u53c2\u6570\u68c0\u67e5\u53ca<\/span>skb<\/span><\/span><\/span>\u5206\u914d\uff0c\u518d\u8c03\u7528\u9a71\u52a8\u7a0b\u5e8f\u7684<\/span>hard_header<\/span><\/span><\/span>\u51fd\u6570\uff08\u5bf9\u4e8e\u4ee5\u592a\u7f51\u9a71\u52a8\u662f<\/span>eth_header()<\/span><\/span><\/span>\u51fd\u6570\uff09\u6765\u6784\u9020\u62a5\u6587\u7684<\/span>MAC<\/span><\/span><\/span>\u5934\u90e8\uff0c\u6b64\u65f6\u7684<\/span>skb->data<\/span><\/span><\/span>\u662f\u6307\u5411<\/span>MAC<\/span><\/span><\/span>\u9996\u90e8\u7684\uff0c\u4e14<\/span>skb->len<\/span><\/span><\/span>\u4e3a<\/span>MAC<\/span><\/span><\/span>\u9996\u90e8\u957f\u5ea6\uff08\u5373<\/span>14<\/span><\/span><\/span>\uff09\u3002\u5bf9\u4e8e\u521b\u5efa\u65f6\u6307\u5b9a<\/span>type<\/span><\/span><\/span>\u4e3a<\/span>SOCK_RAW<\/span><\/span><\/span>\u7c7b\u578b\u5957\u63a5\u5b57\uff0c\u7531\u4e8e\u5728\u53d1\u9001\u65f6\u9700\u8981\u81ea\u884c\u6784\u9020<\/span>MAC<\/span><\/span><\/span>\u5934\u90e8\uff0c\u6240\u4ee5\u5c06<\/span>skb->tail<\/span><\/span><\/span>\u6307\u9488\u6062\u590d\u5230<\/span>MAC<\/span><\/span><\/span>\u9996\u90e8\u5f00\u59cb\u7684\u4f4d\u7f6e\uff0c\u5e76\u5c06<\/span>skb->len<\/span><\/span><\/span>\u8bbe\u7f6e\u4e3a<\/span>0<\/span><\/span><\/span>\uff08\u5373\u4e0d\u4f7f\u7528\u5185\u6838\u6784\u9020\u7684<\/span>MAC<\/span><\/span><\/span>\u9996\u90e8\uff09\u3002\u63a5\u7740\u518d\u8c03\u7528<\/span>memcpy_fromiovec()<\/span><\/span><\/span>\u4ece<\/span>skb->tail<\/span><\/span><\/span>\u7684\u4f4d\u7f6e\u5f00\u59cb\u62f7\u8d1d\u62a5\u6587\u6570\u636e\uff0c\u6700\u7ec8\u8c03\u7528\u7f51\u5361\u9a71\u52a8\u7684\u53d1\u9001\u51fd\u6570\u5c06\u62a5\u6587\u53d1\u9001\u51fa\u53bb\u3002<\/span><\/span><\/span>\n<\/p>\n

                \n\t\u6ce8\uff1a\u5982\u679c\u521b\u5efa\u5957\u63a5\u5b57\u65f6\u6307\u5b9a<\/span><\/span><\/span>type<\/span><\/span><\/span>\u4e3a<\/span><\/span><\/span>SOCK_DGRAM<\/span><\/span><\/span>\uff0c\u5219\u4f7f\u7528\u5185\u6838\u6784\u9020\u7684<\/span><\/span><\/span>MAC<\/span><\/span><\/span>\u9996\u90e8\uff0c\u7528\u6237\u6001\u53d1\u9001\u7684\u6570\u636e\u4e2d\u4e0d\u542b<\/span><\/span><\/span>MAC<\/span><\/span><\/span>\u5934\u90e8\u6570\u636e\u3002<\/span><\/span><\/span>\n<\/p>\n

                \n\t\n<\/p>\n\n\n\n
                \n
                \n

                \n\t\t\t\t\t\t        
                \n<\/span><\/span>\n\t\t\t\t\t<\/p>\n

                \n
                \n
                  \n
                1. \n\t\t\t\t\t\t\t\t\t\u2026\u2026
                  \n<\/span>\n\t\t\t\t\t\t\t\t<\/li>\n
                2. \n\t\t\t\t\t\t\t\t\tres =<\/span> dev–<\/span>><\/span>hard_header(<\/span>skb,<\/span> dev,<\/span> ntohs(<\/span>proto)<\/span>,<\/span> addr,<\/span> NULL<\/span>,<\/span> len<\/span>)<\/span>;<\/span> \/<\/span>\/<\/span>\u6784\u9020MAC\u9996\u90e8 \n\t\t\t\t\t\t\t\t<\/li>\n
                3. \n\t\t\t\t\t\t\t\t\tif<\/span> (<\/span>sock–<\/span>><\/span>type !<\/span>=<\/span> SOCK_DGRAM)<\/span> {<\/span> \n\t\t\t\t\t\t\t\t<\/li>\n
                4. \n\t\t\t\t\t\t\t\t\t        skb–<\/span>><\/span>tail =<\/span> skb–<\/span>><\/span>data;<\/span> \/<\/span>\/<\/span>SOCK_RAW\u7c7b\u578b \n\t\t\t\t\t\t\t\t<\/li>\n
                5. \n\t\t\t\t\t\t\t\t\t        skb–<\/span>><\/span>len<\/span> =<\/span> 0;<\/span> \n\t\t\t\t\t\t\t\t<\/li>\n
                6. \n\t\t\t\t\t\t\t\t\t}<\/span> \n\t\t\t\t\t\t\t\t<\/li>\n
                7. \n\t\t\t\t\t\t\t\t\t\u2026\u2026\n\t\t\t\t\t\t\t\t<\/li>\n
                8. \n\t\t\t\t\t\t\t\t\terr<\/span> =<\/span> memcpy_fromiovec(<\/span>skb_put(<\/span>skb,<\/span>len<\/span>)<\/span>,<\/span> msg–<\/span>><\/span>msg_iov,<\/span> len<\/span>)<\/span>;<\/span> \/<\/span>\/<\/span>\u62f7\u8d1d\u62a5\u6587\u6570\u636e\n\t\t\t\t\t\t\t\t<\/li>\n
                9. \n\t\t\t\t\t\t\t\t\t\u2026\u2026 \n\t\t\t\t\t\t\t\t<\/li>\n
                10. \n\t\t\t\t\t\t\t\t\terr<\/span> =<\/span> dev_queue_xmit(<\/span>skb)<\/span>;<\/span> \/<\/span>\/<\/span>\u53d1\u9001\u62a5\u6587 \n\t\t\t\t\t\t\t\t<\/li>\n
                11. \n\t\t\t\t\t\t\t\t\t\u2026\u2026\n\t\t\t\t\t\t\t\t<\/li>\n<\/ol><\/div>\n<\/p><\/div>\n

                  \n\t\t\t\t\t\t \n\t\t\t\t\t<\/p>\n<\/p><\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

                  \n\t2.2.4  <\/span><\/span><\/span><\/span>\u5176\u5b83<\/span><\/span><\/span> <\/span> <\/span><\/span>\n<\/p>\n

                  \n\ta)         <\/span><\/span><\/span>\u5957\u63a5\u5b57\u7684\u7ed1\u5b9a<\/span><\/span><\/span>\n<\/p>\n

                  \n\t\u94fe\u8def\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u53ef\u8c03\u7528<\/span>bind()<\/span><\/span><\/span>\u51fd\u6570\u8fdb\u884c\u7ed1\u5b9a\uff0c\u8ba9<\/span>packet_type<\/span><\/span><\/span>\u7ed3\u6784<\/span>dev<\/span><\/span><\/span>\u5b57\u6bb5\u6307\u5411\u76f8\u5e94\u7684<\/span>net_device<\/span><\/span><\/span>\u7ed3\u6784\uff0c\u5373\u5c06\u5957\u63a5\u5b57\u7ed1\u5b9a\u5230\u76f8\u5e94\u7684\u7f51\u53e3\u4e0a\u3002\u5982<\/span>2.2.2<\/span><\/span><\/span>\u8282\u62a5\u6587\u63a5\u6536\u7684\u63cf\u8ff0\uff0c\u5728\u63a5\u6536\u65f6\u5982\u679c\u5957\u63a5\u53e3\u6709\u7ed1\u5b9a\u5c31\u9700\u8981\u8fdb\u4e00\u6b65\u786e\u8ba4\u5f53\u524d<\/span>skb->dev<\/span><\/span><\/span>\u662f\u5426\u4e0e\u7ed1\u5b9a\u7f51\u53e3\u76f8\u5339\u914d\uff0c\u53ea\u6709\u5339\u914d\u7684\u624d\u4f1a\u5c06\u62a5\u6587\u4e0a\u9001\u5230\u76f8\u5e94\u7684\u5957\u63a5\u5b57\u3002<\/span><\/span><\/span>\n<\/p>\n

                  \n\tsys_bind()->packet_bind()->packet_do_bind()<\/span><\/span><\/span>\n<\/p>\n

                  \n\tb)        <\/span><\/span><\/span>\u5957\u63a5\u5b57\u9009\u9879<\/span><\/span><\/span>\n<\/p>\n

                  \n\t\u4ee5\u4e0b\u662f\u6bd4\u8f83\u5e38\u7528\u7684\u5957\u63a5\u5b57\u9009\u9879<\/span><\/span><\/span>\n<\/p>\n

                  \n\tPACKET_RX_RING<\/span><\/span><\/span>\uff1a\u7528\u4e8e<\/span>PACKET_MMAP<\/span><\/span><\/span>\u6536\u5305\u65b9\u5f0f\u8bbe\u7f6e\u63a5\u6536\u73af\u5f62\u961f\u5217<\/span><\/span><\/span>\n<\/p>\n

                  \n\t<\/a>PACKET_STATISTICS<\/span><\/span><\/span><\/span><\/span>\uff1a\u7528\u4e8e\u8bfb\u53d6\u6536\u5305\u7edf\u8ba1\u4fe1\u606f<\/span><\/span><\/span>\n<\/p>\n

                  \n\t<\/span><\/span><\/span>\n<\/p>\n

                  \n\tc)       <\/span><\/span><\/span>\u4fe1\u606f\u67e5\u770b<\/span><\/span><\/span>\n<\/p>\n

                  \n\t\u94fe\u8def\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u7684\u4fe1\u606f\u53ef\u901a\u8fc7<\/span><\/span><\/span>\/proc\/net\/packet<\/span><\/span><\/span>\u8fdb\u884c\u67e5\u770b\u3002\u5982\u4e0b\u4e3a\u56fe<\/span><\/span><\/span>2<\/span><\/span><\/span>\u548c\u56fe<\/span><\/span><\/span>3<\/span><\/span><\/span>\u4e2d\u521b\u5efa\u7684\u539f\u59cb\u5957\u63a5\u5b57\u7684\u4fe1\u606f\uff0c\u53ef\u4ee5\u67e5\u770b\u5230\u521b\u5efa\u65f6\u6307\u5b9a\u7684\u534f\u8bae\u7c7b\u578b\u3001\u662f\u5426\u7ed1\u5b9a\u7f51\u53e3\u3001\u5df2\u4f7f\u7528\u7684\u63a5\u6536\u7f13\u5b58\u5927\u5c0f\u7b49\u4fe1\u606f\u3002\u8fd9\u4e9b\u4fe1\u606f\u5bf9\u4e8e\u5206\u6790\u548c\u5b9a\u4f4d\u95ee\u9898\u6709\u5e2e\u52a9\u3002<\/span><\/span><\/span> <\/span><\/span><\/span>\n<\/p>\n

                  \n
                  \n
                  \n
                    \n
                  1. \n\t\t\t\t\tcat \/proc\/net\/packet\n\t\t\t\t<\/li>\n
                  2. \n\t\t\t\t\tsk RefCnt Type Proto Iface R Rmem User Inode\n\t\t\t\t<\/li>\n
                  3. \n\t\t\t\t\tffff810007df8400 3 3 0810 0 1 0 0 1310\n\t\t\t\t<\/li>\n
                  4. \n\t\t\t\t\tffff810007df8800 3 3 0806 0 1 0 0 1309\n\t\t\t\t<\/li>\n
                  5. \n\t\t\t\t\tffff810007df8c00 3 3 0800 0 1 560 0 1308\n\t\t\t\t<\/li>\n
                  6. \n\t\t\t\t\tffff810007df8000 3 3 0003 0 1 560 0 1307\n\t\t\t\t<\/li>\n
                  7. \n\t\t\t\t\tffff810007df3800 3 3 0003 0 1 560 0 1306\n\t\t\t\t<\/li>\n<\/ol><\/div>\n<\/p><\/div>\n<\/div>\n

                    \n\t \n<\/p>\n

                    2.3  <\/span><\/span><\/span><\/span>\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u7684\u5b9e\u73b0<\/span><\/span><\/span> <\/span><\/span><\/span>2.3.1  <\/span><\/span><\/span><\/span>\u5957\u63a5\u5b57\u521b\u5efa<\/span><\/span><\/span> <\/span><\/span><\/span> <\/p>\n

                    \n\t\u5982\u56fe<\/span>4<\/span><\/span><\/span>\u6240\u793a\uff0c\u5728<\/span>IPV4<\/span><\/span><\/span>\u534f\u8bae\u6808\u4e2d\u4e00\u4e2a\u4f20\u8f93\u5c42\u534f\u8bae\uff08\u5982<\/span>TCP<\/span><\/span><\/span>\uff0c<\/span>UDP<\/span><\/span><\/span>\uff0c<\/span>UDP-Lite<\/span><\/span><\/span>\u7b49\uff09\u5bf9\u5e94\u4e00\u4e2a<\/span>inet_protosw<\/span><\/span><\/span>\u7ed3\u6784\uff0c\u800c<\/span>inet_protosw<\/span><\/span><\/span>\u7ed3\u6784\u4e2d\u53c8\u5305\u542b\u4e86<\/span>proto_ops<\/span><\/span><\/span>\u7ed3\u6784\u548c<\/span>proto<\/span><\/span><\/span>\u7ed3\u6784\u3002\u7f51\u7edc\u5b50\u7cfb\u7edf\u521d\u59cb\u5316\u65f6\u5c06\u6240\u6709\u7684<\/span>inet_protosw<\/span><\/span><\/span>\u7ed3\u6784<\/span>hash<\/span><\/span><\/span>\u5230\u5168\u5c40\u7684<\/span>inetsw[]<\/span><\/span><\/span>\u6570\u7ec4\u4e2d\u3002<\/span>proto_ops<\/span><\/span><\/span>\u7ed3\u6784\u5b9e\u73b0\u7684\u662f\u4ece\u4e0e\u534f\u8bae\u65e0\u5173\u7684\u5957\u63a5\u53e3\u5c42\u5230\u534f\u8bae\u76f8\u5173\u7684\u4f20\u8f93\u5c42\u7684\u8f6c\u63a5\uff0c\u800c<\/span>proto<\/span><\/span><\/span>\u7ed3\u6784\u53c8\u5c06\u4f20\u8f93\u5c42\u6620\u5c04\u5230\u7f51\u7edc\u5c42\u3002<\/span><\/span><\/span>\n<\/p>\n

                    \n\t<\/span><\/span><\/span>\n<\/p>\n

                    \n\t\"4\"<\/a> <\/span><\/span><\/span>\n<\/p>\n

                    \n\t\u56fe<\/span><\/span><\/span>4  <\/span>inetsw[]<\/span><\/span><\/span>\u6570\u7ec4\u7ed3\u6784<\/span><\/span><\/span> <\/span><\/span><\/span>\n<\/p>\n

                    \n\t<\/span><\/span><\/span>\n<\/p>\n

                    \n\t    \u8c03\u7528<\/span>socket()<\/span><\/span><\/span>\u51fd\u6570\u521b\u5efa\u5957\u63a5\u5b57\u7684\u6d41\u7a0b\u5982\u4e0b\uff0c\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u6700\u7ec8\u7531<\/span>inet_create()<\/span><\/span><\/span>\u521b\u5efa\u3002<\/span><\/span><\/span>\n<\/p>\n

                    \n\tsys_socket()->sock_create()->__sock_create()->inet_create()<\/span><\/span><\/span>\n<\/p>\n

                    \n\t<\/span><\/span><\/span>\n<\/p>\n

                    \n\t    inet_create()<\/span><\/span><\/span>\u51fd\u6570\u9664\u7528\u4e8e\u521b\u5efa\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u5916\uff0c\u8fd8\u7528\u4e8e\u521b\u5efa<\/span>TCP<\/span><\/span><\/span>\u3001<\/span>UDP<\/span><\/span><\/span>\u5957\u63a5\u5b57\u3002\u9996\u5148\u6839\u636e<\/span>socket()<\/span><\/span><\/span>\u51fd\u6570\u7684\u7b2c\u4e8c\u4e2a\u53c2\u6570\uff08\u5373<\/span>SOCK_RAW<\/span><\/span><\/span>\uff09\u5728<\/span>inetsw[]<\/span><\/span><\/span>\u6570\u7ec4\u4e2d\u5339\u914d\u5230\u76f8\u5e94\u7684<\/span>inet_protosw<\/span><\/span><\/span>\u7ed3\u6784\u3002\u5e76\u5c06\u5957\u63a5\u5b57\u7ed3\u6784\u7684<\/span>ops<\/span><\/span><\/span>\u8bbe\u7f6e\u4e3a<\/span>inet_sockraw_ops<\/span><\/span><\/span>\uff0c\u5c06\u5957\u63a5\u5b57\u7ed3\u6784\u7684<\/span>sk_prot<\/span><\/span><\/span>\u8bbe\u7f6e\u4e3a<\/span>raw_prot<\/span><\/span><\/span>\u3002\u7136\u540e\u5bf9\u4e8e<\/span>SOCK_RAW<\/span><\/span><\/span>\u7c7b\u578b\u5957\u63a5\u5b57\uff0c\u8fd8\u8981\u5c06<\/span>inet->num<\/span><\/span><\/span>\u8bbe\u7f6e\u4e3a\u534f\u8bae\u7c7b\u578b\uff0c\u4ee5\u4fbf\u6700\u540e\u80fd\u8c03\u7528<\/span>proto<\/span><\/span><\/span>\u7ed3\u6784\u7684<\/span>hash<\/span><\/span><\/span>\u51fd\u6570\uff08\u5373<\/span>raw_v4_hash()<\/span><\/span><\/span>\uff09\u3002<\/span><\/span><\/span>\n<\/p>\n

                    \n\t\n<\/p>\n\n\n\n
                    \n
                    \n

                    \n\t\t\t\t\t\t        
                    \n<\/span><\/span>\n\t\t\t\t\t<\/p>\n

                    \n
                    \n
                      \n
                    1. \n\t\t\t\t\t\t\t\t\t\u2026\u2026
                      \n<\/span>\n\t\t\t\t\t\t\t\t<\/li>\n
                    2. \n\t\t\t\t\t\t\t\t\tsock–<\/span>><\/span>ops =<\/span> answer–<\/span>><\/span>ops;<\/span> \/<\/span>\/<\/span>\u5c06socket\u7ed3\u6784\u7684ops\u8bbe\u7f6e\u4e3ainet_sockraw_ops \n\t\t\t\t\t\t\t\t<\/li>\n
                    3. \n\t\t\t\t\t\t\t\t\tanswer_prot =<\/span> answer–<\/span>><\/span>prot;<\/span> \n\t\t\t\t\t\t\t\t<\/li>\n
                    4. \n\t\t\t\t\t\t\t\t\t\u2026\u2026 \n\t\t\t\t\t\t\t\t<\/li>\n
                    5. \n\t\t\t\t\t\t\t\t\tif<\/span> (<\/span>SOCK_RAW =<\/span>=<\/span> sock–<\/span>><\/span>type)<\/span> {<\/span> \/<\/span>\/<\/span>SOCK_RAW\u7c7b\u578b\u7684\u5957\u63a5\u5b57\uff0c\u8bbe\u7f6einet–<\/span>><\/span>num \n\t\t\t\t\t\t\t\t<\/li>\n
                    6. \n\t\t\t\t\t\t\t\t\t        inet–<\/span>><\/span>num =<\/span> protocol;<\/span> \n\t\t\t\t\t\t\t\t<\/li>\n
                    7. \n\t\t\t\t\t\t\t\t\t        if<\/span> (<\/span>IPPROTO_RAW =<\/span>=<\/span> protocol)<\/span> \/<\/span>\/<\/span>protocol\u4e3aIPPROTO_RAW\u7684\u7279\u6b8a\u5904\u7406\uff0c \n\t\t\t\t\t\t\t\t<\/li>\n
                    8. \n\t\t\t\t\t\t\t\t\t                inet–<\/span>><\/span>hdrincl =<\/span> 1;<\/span> \u540e\u7eed\u5728\u62a5\u6587\u53d1\u9001\u65f6\u4f1a\u518d\u8bb2\u5230 \n\t\t\t\t\t\t\t\t<\/li>\n
                    9. \n\t\t\t\t\t\t\t\t\t}<\/span> \n\t\t\t\t\t\t\t\t<\/li>\n
                    10. \n\t\t\t\t\t\t\t\t\t\u2026\u2026\n\t\t\t\t\t\t\t\t<\/li>\n
                    11. \n\t\t\t\t\t\t\t\t\tif<\/span> (<\/span>inet–<\/span>><\/span>num)<\/span> {<\/span>\n\t\t\t\t\t\t\t\t<\/li>\n
                    12. \n\t\t\t\t\t\t\t\t\t        <\/span>inet–<\/span>><\/span>sport =<\/span> htons(<\/span>inet–<\/span>><\/span>num)<\/span>;<\/span> \n\t\t\t\t\t\t\t\t<\/li>\n
                    13. \n\t\t\t\t\t\t\t\t\t        sk–<\/span>><\/span>sk_prot–<\/span>><\/span>hash(<\/span>sk)<\/span>;<\/span> \/<\/span>\/<\/span>\u8c03\u7528raw_v4_hash(<\/span>)<\/span>\u51fd\u6570\u5c06\u5957\u63a5\u5b57\u94fe\u5230raw_v4_htable\u4e2d \n\t\t\t\t\t\t\t\t<\/li>\n
                    14. \n\t\t\t\t\t\t\t\t\t}<\/span> \n\t\t\t\t\t\t\t\t<\/li>\n
                    15. \n\t\t\t\t\t\t\t\t\t\u2026\u2026\n\t\t\t\t\t\t\t\t<\/li>\n<\/ol><\/div>\n<\/p><\/div>\n

                      \n\t\t\t\t\t\t \n\t\t\t\t\t<\/p>\n<\/p><\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

                      \u7ecf\u8fc7\u5982\u4e0a\u64cd\u4f5c\u540e\uff0c\u76f8\u5e94\u7684\u5957\u63a5\u5b57\u7ed3\u6784<\/span>sock<\/span><\/span><\/span>\u4f1a\u901a\u8fc7<\/span>raw_v4_hash()<\/span><\/span><\/span>\u51fd\u6570\u94fe\u5230<\/span>raw_v4_htable<\/span><\/span><\/span>\u94fe\u8868\u4e2d\uff0c\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u62a5\u6587\u63a5\u6536\u65f6\u9700\u8981\u4f7f\u7528\u5230<\/span>raw_v4_htable<\/span><\/span><\/span>\u3002\u5982\u56fe<\/span>5<\/span><\/span><\/span>\u6240\u793a\uff0c\u5171\u521b\u5efa\u4e86<\/span>3<\/span><\/span><\/span>\u4e2a\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\uff0c\u534f\u8bae\u7c7b\u578b\u5206\u522b\u4e3a<\/span><\/a><\/a>IPPROTO_TCP<\/span><\/span><\/span><\/span><\/span><\/span><\/span>\u3001<\/span>IPPROTO_ICMP<\/span><\/span><\/span>\u548c<\/span>89<\/span><\/span><\/span>\u3002<\/span><\/span><\/span> <\/p>\n

                      \n\t<\/span><\/span><\/span>\n<\/p>\n

                      \n\t\"5\"<\/a> <\/span><\/span><\/span>\n<\/p>\n

                      \n\t\u56fe<\/span><\/span><\/span>5  <\/span>raw_v4_htable<\/span><\/span><\/span>\u94fe\u8868<\/span><\/span><\/span> <\/span><\/span><\/span>\n<\/p>\n

                      \n\t<\/span><\/span><\/span>\n<\/p>\n

                      \n\t \n<\/p>\n

                      2.3.2  <\/span><\/span><\/span><\/span>\u62a5\u6587\u63a5\u6536<\/span><\/span><\/span> <\/span><\/span><\/span> <\/p>\n

                      \n\t\u7f51\u5361\u9a71\u52a8\u6536\u5230\u62a5\u6587\u540e\u5728\u8f6f\u4e2d\u65ad\u4e0a\u4e0b\u6587\u7531<\/span>netif_receive_skb()<\/span><\/span><\/span>\u5904\u7406\uff0c\u5bf9\u4e8e<\/span>IP<\/span><\/span><\/span>\u62a5\u6587\u4e14\u76ee\u7684\u5730\u5740\u4e3a\u672c\u673a\u7684\u4f1a\u7531<\/span>ip_rcv()<\/span><\/span><\/span>\u6700\u7ec8\u8c03\u7528<\/span>ip_local_deliver_finish()<\/span><\/span><\/span>\u51fd\u6570\u3002<\/span>ip_local_deliver_finish()<\/span><\/span><\/span>\u4e3b\u8981\u529f\u80fd\u7684\u4ee3\u7801\u7247\u6bb5\u5982\u4e0b\uff0c\u5148\u6839\u636e\u62a5\u6587\u7684<\/span>L4<\/span><\/span><\/span>\u5c42\u534f\u8bae\u7c7b\u578b<\/span>hash<\/span><\/span><\/span>\u503c\u5728\u56fe<\/span>5<\/span><\/span><\/span>\u4e2d\u7684<\/span>raw_v4_htable<\/span><\/span><\/span>\u8868\u4e2d\u67e5\u627e\u662f\u5426\u6709\u5339\u914d\u7684<\/span>sock<\/span><\/span><\/span>\u3002\u5982\u679c\u6709\u5339\u914d\u7684<\/span>sock<\/span><\/span><\/span>\u7ed3\u6784\uff0c\u5c31\u8fdb\u4e00\u6b65\u8c03\u7528<\/span>raw_v4_input()<\/span><\/span><\/span>\u5904\u7406\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u3002\u4e0d\u7ba1\u662f\u5426\u6709\u539f\u59cb\u5957\u63a5\u5b57\u8981\u5904\u7406\uff0c\u8be5\u62a5\u6587\u90fd\u4f1a\u8d70\u540e\u7eed\u7684\u534f\u8bae\u6808\u5904\u7406\u6d41\u7a0b\u3002\u5373\u4f1a\u7ee7\u7eed\u5339\u914d<\/span>inet_protos[]<\/span><\/span><\/span>\u6570\u7ec4\uff0c\u6839\u636e<\/span>L4<\/span><\/span><\/span>\u5c42\u534f\u8bae\u7c7b\u578b\u8d70<\/span>TCP<\/span><\/span><\/span>\u3001<\/span>UDP<\/span><\/span><\/span>\u3001<\/span>ICMP<\/span><\/span><\/span>\u7b49\u4e0d\u540c\u5904\u7406\u6d41\u7a0b\u3002<\/span><\/span><\/span>\n<\/p>\n

                      \n\t\n<\/p>\n\n\n\n
                      \n
                      \n

                      \n\t\t\t\t\t\t        
                      \n<\/span><\/span>\n\t\t\t\t\t<\/p>\n

                      \n
                      \n
                        \n
                      1. \n\t\t\t\t\t\t\t\t\t\u2026\u2026
                        \n<\/span>\n\t\t\t\t\t\t\t\t<\/li>\n
                      2. \n\t\t\t\t\t\t\t\t\thash =<\/span> protocol &<\/span> (<\/span>MAX_INET_PROTOS –<\/span> 1)<\/span>;<\/span> \/<\/span>\/<\/span>\u6839\u636e\u62a5\u6587\u534f\u8bae\u7c7b\u578b\u53d6hash\u503c \n\t\t\t\t\t\t\t\t<\/li>\n
                      3. \n\t\t\t\t\t\t\t\t\traw_sk =<\/span> sk_head(<\/span>&<\/span>raw_v4_htable[<\/span>hash]<\/span>)<\/span>;<\/span> \/<\/span>\/<\/span>\u5728raw_v4_htable\u4e2d\u67e5\u627e \n\t\t\t\t\t\t\t\t<\/li>\n
                      4. \n\t\t\t\t\t\t\t\t\t\u2026\u2026 \n\t\t\t\t\t\t\t\t<\/li>\n
                      5. \n\t\t\t\t\t\t\t\t\tif<\/span> (<\/span>raw_sk &<\/span>&<\/span> !<\/span>raw_v4_input(<\/span>skb,<\/span> skb–<\/span>><\/span>nh.<\/span>iph,<\/span> hash)<\/span>)<\/span> \/<\/span>\/<\/span>\u5904\u7406\u539f\u59cb\u5957\u63a5\u5b57 \n\t\t\t\t\t\t\t\t<\/li>\n
                      6. \n\t\t\t\t\t\t\t\t\t\u2026\u2026 \n\t\t\t\t\t\t\t\t<\/li>\n
                      7. \n\t\t\t\t\t\t\t\t\tif<\/span> (<\/span>(<\/span>ipprot =<\/span> rcu_dereference(<\/span>inet_protos[<\/span>hash]<\/span>)<\/span>)<\/span> !<\/span>=<\/span> NULL<\/span>)<\/span> {<\/span> \/<\/span>\/<\/span>\u5339\u914dinet_protos[<\/span>]<\/span>\u6570\u7ec4 \n\t\t\t\t\t\t\t\t<\/li>\n
                      8. \n\t\t\t\t\t\t\t\t\t        \u2026\u2026 \n\t\t\t\t\t\t\t\t<\/li>\n
                      9. \n\t\t\t\t\t\t\t\t\t        ret =<\/span> ipprot–<\/span>><\/span>handler(<\/span>skb)<\/span>;<\/span> \/<\/span>\/<\/span>\u8c03\u7528\u4f20\u8f93\u5c42\u5904\u7406\u51fd\u6570 \n\t\t\t\t\t\t\t\t<\/li>\n
                      10. \n\t\t\t\t\t\t\t\t\t        \u2026\u2026 \n\t\t\t\t\t\t\t\t<\/li>\n
                      11. \n\t\t\t\t\t\t\t\t\t}<\/span> else<\/span> {<\/span> \/<\/span>\/<\/span>\u5982\u679c\u5728inet_protos[<\/span>]<\/span>\u6570\u7ec4\u4e2d\u672a\u5339\u914d\u5230\uff0c\u5219\u91ca\u653e\u62a5\u6587\n\t\t\t\t\t\t\t\t<\/li>\n
                      12. \n\t\t\t\t\t\t\t\t\t        \u2026\u2026 \n\t\t\t\t\t\t\t\t<\/li>\n
                      13. \n\t\t\t\t\t\t\t\t\t        kfree_skb(<\/span>skb)<\/span>;<\/span> \n\t\t\t\t\t\t\t\t<\/li>\n
                      14. \n\t\t\t\t\t\t\t\t\t}<\/span> \n\t\t\t\t\t\t\t\t<\/li>\n
                      15. \n\t\t\t\t\t\t\t\t\t\u2026\u2026\n\t\t\t\t\t\t\t\t<\/li>\n<\/ol><\/div>\n<\/p><\/div>\n

                        \n\t\t\t\t\t\t \n\t\t\t\t\t<\/p>\n<\/p><\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

                        \u5982\u56fe<\/span>6<\/span><\/span><\/span>\u6240\u793a\u7684<\/span>inet_protos[]<\/span><\/span><\/span>\u6570\u7ec4\uff0c\u6bcf\u9879\u7531<\/span>net_protocol<\/span><\/span><\/span>\u7ed3\u6784\u7ec4\u6210\u3002\u8868\u793a\u4e00\u4e2a\u534f\u8bae\uff08\u5305\u62ec\u4f20\u8f93\u5c42\u534f\u8bae\u548c\u7f51\u7edc\u5c42\u9644\u5c5e\u534f\u8bae\uff09\u7684\u63a5\u6536\u5904\u7406\u51fd\u6570\u96c6\uff0c\u4e00\u822c\u5305\u62ec\u4e00\u4e2a\u6b63\u5e38\u63a5\u6536\u51fd\u6570\u548c\u4e00\u4e2a\u51fa\u9519\u63a5\u6536\u51fd\u6570\u3002\u56fe\u4e2d<\/span>TCP<\/span><\/span><\/span>\u3001<\/span>UDP<\/span><\/span><\/span>\u548c<\/span>ICMP<\/span><\/span><\/span>\u534f\u8bae\u7684\u63a5\u6536\u5904\u7406\u51fd\u6570\u5206\u522b\u4e3a<\/span>tcp_v4_rcv()<\/span><\/span><\/span>\u3001<\/span>udp_rcv()<\/span><\/span><\/span>\u548c<\/span>icmp_rcv()<\/span><\/span><\/span>\u3002\u5982\u679c\u5728<\/span>inet_protos[]<\/span><\/span><\/span>\u6570\u7ec4\u4e2d\u672a\u914d\u7f6e\u5230\u76f8\u5e94\u7684<\/span>net_protocol<\/span><\/span><\/span>\u7ed3\u6784\uff0c\u62a5\u6587\u5c31\u4f1a\u88ab\u4e22\u5f03\u6389\u3002\u6bd4\u5982<\/span>OSPF<\/span><\/span><\/span>\u62a5\u6587\uff08\u534f\u8bae\u7c7b\u578b\u4e3a<\/span>89<\/span><\/span><\/span>\uff09\u5728<\/span>inet_protos[]<\/span><\/span><\/span>\u6570\u7ec4\u4e2d\u6ca1\u6709\u76f8\u5e94\u7684\u9879\uff0c\u5185\u6838\u4f1a\u5c06\u5176\u4e22\u5f03\u6389\uff0c\u8fd9\u79cd\u62a5\u6587\u53ea\u80fd\u63d0\u4f9b\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u63a5\u6536\u5230\u7528\u6237\u6001\u6765\u5904\u7406\u3002<\/span><\/span><\/span> <\/p>\n

                        \n\t<\/span><\/span><\/span>\n<\/p>\n

                        \n\t\"6\"<\/a> <\/span><\/span><\/span>\n<\/p>\n

                        \n\t\u56fe<\/span><\/span><\/span>6  <\/span>inet_protos[]<\/span><\/span><\/span>\u6570\u7ec4\u7ed3\u6784<\/span><\/span><\/span> <\/span><\/span><\/span>\n<\/p>\n

                        \n\t<\/span><\/span><\/span>\n<\/p>\n

                        \n\t    \u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u7684\u603b\u4f53\u63a5\u6536\u6d41\u7a0b\u5982\u4e0b\uff0c\u6700\u7ec8\u4f1a\u5c06<\/span>skb<\/span><\/span><\/span>\u6302\u5230\u76f8\u5e94\u5957\u63a5\u5b57\u4e0a\uff0c\u5e76\u5524\u9192\u7528\u6237\u6001\u8fdb\u7a0b\u8bfb\u53d6\u62a5\u6587\u6570\u636e\u3002<\/span><\/span><\/span>\n<\/p>\n

                        \n\t\u7f51\u5361\u9a71\u52a8<\/span>->netif_receive_skb()->ip_rcv()->ip_rcv_finish()->ip_local_deliver()->ip_local<\/span><\/span><\/span>\n<\/p>\n

                        \n\t_deliver_finish()->raw_v4_input()->raw_rcv()->raw_rcv_skb()->sock_queue_rcv_skb()<\/span><\/span><\/span>\n<\/p>\n

                        \n\t\n<\/p>\n\n\n\n
                        \n
                        \n\t\t\t\t\t<\/p>\n
                        \n
                        \n
                          \n
                        1. \n\t\t\t\t\t\t\t\t\t\u2026\u2026
                          \n<\/span>\n\t\t\t\t\t\t\t\t<\/li>\n
                        2. \n\t\t\t\t\t\t\t\t\tskb_queue_tail(<\/span>&<\/span>sk–<\/span>><\/span>sk_receive_queue,<\/span> skb)<\/span>;<\/span> \/<\/span>\/<\/span>\u6302\u5230\u63a5\u6536\u961f\u5217 \n\t\t\t\t\t\t\t\t<\/li>\n
                        3. \n\t\t\t\t\t\t\t\t\tif<\/span> (<\/span>!<\/span>sock_flag(<\/span>sk,<\/span> SOCK_DEAD)<\/span>)<\/span> \n\t\t\t\t\t\t\t\t<\/li>\n
                        4. \n\t\t\t\t\t\t\t\t\t        sk–<\/span>><\/span>sk_data_ready(<\/span>sk,<\/span> skb_len)<\/span>;<\/span> \/<\/span>\/<\/span>\u5524\u9192\u7528\u6237\u6001\u8fdb\u7a0b \n\t\t\t\t\t\t\t\t<\/li>\n
                        5. \n\t\t\t\t\t\t\t\t\t\u2026\u2026\n\t\t\t\t\t\t\t\t<\/li>\n<\/ol><\/div>\n<\/p><\/div>\n<\/p><\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

                          \n\t       <\/span><\/span><\/span><\/span>\u4e0a\u9762\u4ecb\u7ecd\u4e86\u62a5\u6587\u63a5\u6536\u5728\u8f6f\u4e2d\u65ad\u7684\u5904\u7406\u6d41\u7a0b\uff0c\u4e0b\u9762\u4ecb\u7ecd\u7528\u6237\u6001\u8fdb\u7a0b\u8bfb\u53d6\u62a5\u6587\u662f\u5982\u4f55\u5b9e\u73b0\u7684\u3002\u7528\u6237\u6001\u7684<\/span>recvmsg()<\/span><\/span><\/span>\u6700\u7ec8\u4f1a\u8c03\u7528<\/span>raw_recvmsg()<\/span><\/span><\/span>\uff0c\u540e\u8005\u518d\u8c03\u7528<\/span>skb_recv_datagram<\/span><\/span><\/span>\u3002\u5982\u679c\u5957\u63a5\u5b57\u63a5\u6536\u961f\u5217<\/span>sk->sk_receive_queue<\/span><\/span><\/span>\u4e2d\u6709\u62a5\u6587\u5c31\u53d6<\/span>skb<\/span><\/span><\/span>\u5e76\u8fd4\u56de\u3002\u5426\u5219\u8c03\u7528<\/span>wait_for_packet()<\/span><\/span><\/span>\u7b49\u5f85\uff0c\u76f4\u5230\u5185\u6838\u8f6f\u4e2d\u65ad\u6536\u5230\u62a5\u6587\u5e76\u5524\u9192\u7528\u6237\u6001\u8fdb\u7a0b\u3002<\/span><\/span><\/span>\n<\/p>\n

                          \n\tsys_recvmsg()->sock_recvmsg()->\u2026->sock_common_recvmsg()->raw_recvmsg()<\/span><\/span><\/span>\n<\/p>\n

                          \n\t<\/span><\/span><\/span>\n<\/p>\n

                          \n\t \n<\/p>\n

                          2.3.3  <\/span><\/span><\/span><\/span>\u62a5\u6587\u53d1\u9001<\/span><\/span><\/span> <\/span><\/span><\/span> <\/p>\n

                          \n\t\u7528\u6237\u6001\u8c03\u7528<\/span>sendto()<\/span><\/span><\/span>\u6216<\/span>sendmsg()<\/span><\/span><\/span>\u53d1\u9001\u62a5\u6587\u7684\u5185\u6838\u6001\u5904\u7406\u6d41\u7a0b\u5982\u4e0b\uff0c\u6700\u7ec8\u7531<\/span>raw_sendmsg()<\/span><\/span><\/span>\u8fdb\u884c\u53d1\u9001\u3002<\/span><\/span><\/span>\n<\/p>\n

                          \n\tsys_sendto()->sock_sendmsg()->__sock_sendmsg()->inet_sendmsg()->raw_sendmsg()<\/span><\/span><\/span>\n<\/p>\n

                          \n\t    <\/span><\/span><\/span><\/span>\u6b64\u51fd\u6570\u5148\u8fdb\u884c\u4e00\u4e9b\u53c2\u6570\u5408\u6cd5\u6027\u68c0\u6d4b\uff0c\u7136\u540e\u8c03\u7528<\/span>ip_route_output_slow()<\/span><\/span><\/span>\u8fdb\u884c\u9009\u8def\u3002\u9009\u8def\u6210\u529f\u540e\u4e3b\u8981\u6267\u884c\u5982\u4e0b\u4ee3\u7801\u7247\u6bb5\uff0c\u6839\u636e<\/span>inet->hdrincl<\/span><\/span><\/span>\u662f\u5426\u8bbe\u7f6e\u8d70\u4e0d\u540c\u7684\u6d41\u7a0b\u3002<\/span><\/span><\/span>raw_send_hdrinc()<\/span><\/span><\/span>\u51fd\u6570\u8868\u793a\u7528\u6237\u6001\u53d1\u9001\u7684\u6570\u636e\u4e2d\u9700\u8981\u5305\u542b<\/span><\/span><\/span>IP<\/span><\/span><\/span>\u9996\u90e8\uff0c\u5373\u7531\u8c03\u7528\u8005\u5728\u53d1\u9001\u65f6\u81ea\u884c\u6784\u9020<\/span><\/span><\/span>IP<\/span><\/span><\/span>\u9996\u90e8\u3002\u5982\u679c<\/span>inet->hdrincl<\/span><\/span><\/span>\u672a\u7f6e\u4f4d\uff0c\u8868\u793a\u5185\u6838\u4f1a\u6784\u9020<\/span>IP<\/span><\/span><\/span>\u9996\u90e8\uff0c\u5373\u8c03\u7528\u8005\u53d1\u9001\u7684\u6570\u636e\u4e2d\u4e0d\u5305\u542b<\/span>IP<\/span><\/span><\/span>\u9996\u90e8\u3002\u4e0d\u7ba1\u8d70\u54ea\u4e2a\u6d41\u7a0b\uff0c\u6700\u7ec8\u90fd\u4f1a\u7ecf\u8fc7<\/span>ip_output()->ip_finish_output()->\u2026->dev_queue_xmit()<\/span><\/span><\/span>\u5c06\u62a5\u6587\u4ea4\u7ed9\u7f51\u5361\u9a71\u52a8\u7684\u53d1\u9001\u51fd\u6570\u53d1\u9001\u51fa\u53bb\u3002<\/span><\/span><\/span>\n<\/p>\n

                          \n\t<\/span><\/span><\/span> \n<\/p>\n

                          \n
                          \n
                            \n
                          1. \n\t\t\t\t\u2026\u2026
                            \n<\/span>\n\t\t\t<\/li>\n
                          2. \n\t\t\t\tif<\/span> (<\/span>inet–<\/span>><\/span>hdrincl)<\/span> {<\/span> \/<\/span>\/<\/span>\u8c03\u7528\u8005\u8981\u6784\u9020IP\u9996\u90e8 \n\t\t\t<\/li>\n
                          3. \n\t\t\t\t        err<\/span> =<\/span> raw_send_hdrinc(<\/span>sk,<\/span> msg–<\/span>><\/span>msg_iov,<\/span> len<\/span>,<\/span> \n\t\t\t<\/li>\n
                          4. \n\t\t\t\t                              rt,<\/span> msg–<\/span>><\/span>msg_flags)<\/span>;<\/span> \n\t\t\t<\/li>\n
                          5. \n\t\t\t\t}<\/span> else<\/span> {<\/span> \n\t\t\t<\/li>\n
                          6. \n\t\t\t\t        \u2026\u2026 \/<\/span>\/<\/span>\u7531\u5185\u6838\u6784\u9020IP\u9996\u90e8 \n\t\t\t<\/li>\n
                          7. \n\t\t\t\t       err<\/span> =<\/span> ip_push_pending_frames(<\/span>sk)<\/span>;<\/span> \n\t\t\t<\/li>\n
                          8. \n\t\t\t\t}<\/span> \n\t\t\t<\/li>\n
                          9. \n\t\t\t\t\u2026\u2026\n\t\t\t<\/li>\n<\/ol><\/div>\n<\/div>\n

                            \n\t   \u6ce8\uff1a<\/span>inet->hdrincl<\/span><\/span><\/span>\u7f6e\u4f4d\u8868\u793a\u7528\u6237\u6001\u53d1\u9001\u7684\u6570\u636e\u4e2d\u8981\u5305\u542b<\/span>IP<\/span><\/span><\/span>\u9996\u90e8\uff0c<\/span>inet->hdrincl<\/span><\/span><\/span>\u5728\u4ee5\u4e0b\u4e24\u79cd\u60c5\u51b5\u4e0b\u88ab\u7f6e\u4f4d\u3002<\/span><\/span><\/span>\n<\/p>\n

                            \n\t    <\/span>a). <\/span><\/span><\/span>\u7ed9\u5957\u63a5\u5b57\u8bbe\u7f6e<\/span>IP_HDRINCL<\/span><\/span><\/span>\u9009\u9879<\/span><\/span><\/span>\n<\/p>\n

                            \n\t       <\/span>   <\/span>setsockopt (sockfd, IPPROTO_IP, IP_HDRINCL, &val, sizeof(val))<\/span><\/span><\/span>\n<\/p>\n

                            \n\t    <\/span>b). <\/span><\/span><\/span>\u8c03\u7528<\/span>socket()<\/span><\/span><\/span>\u521b\u5efa\u5957\u63a5\u5b57\u65f6\uff0c\u7b2c\u4e09\u4e2a\u53c2\u6570\u6307\u5b9a\u4e3a<\/span>IPPROTO_RAW<\/span><\/span><\/span>\uff0c\u89c1<\/span>2.3.1<\/span><\/span><\/span>\u8282\u3002<\/span><\/span><\/span>\n<\/p>\n

                            \n\t       <\/span>   <\/span>socktet(PF_INET, SOCK_RAW, IPPROTO_RAW)<\/span><\/span><\/span>\n<\/p>\n

                            \n\t<\/span><\/span><\/span>\n<\/p>\n

                            \n\t \n<\/p>\n

                            2.3.4  <\/span><\/span><\/span><\/span>\u5176\u5b83<\/span><\/span><\/span> <\/span><\/span><\/span> <\/p>\n

                            \n\ta)       <\/span><\/span><\/span>\u5957\u63a5\u5b57\u7ed1\u5b9a<\/span><\/span><\/span>\n<\/p>\n

                            \n\t\u82e5\u539f\u59cb\u5957\u63a5\u5b57\u8c03\u7528<\/span>bind()<\/span><\/span><\/span>\u7ed1\u5b9a\u4e86\u4e00\u4e2a\u5730\u5740\uff0c\u5219\u8be5\u5957\u63a5\u53e3\u53ea\u80fd\u6536\u5230\u76ee\u7684<\/span>IP<\/span><\/span><\/span>\u5730\u5740\u4e0e\u7ed1\u5b9a\u5730\u5740\u76f8\u5339\u914d\u7684\u62a5\u6587\u3002\u5185\u6838\u7684\u5177\u4f53\u5b9e\u73b0\u662f<\/span>raw_bind()<\/span><\/span><\/span>\uff0c\u5c06<\/span>inet->rcv_saddr<\/span><\/span><\/span>\u8bbe\u7f6e\u4e3a\u7ed1\u5b9a\u5730\u5740\u3002\u5728\u539f\u59cb\u5957\u63a5\u5b57\u63a5\u6536\u65f6\uff0c<\/span>__raw_v4_lookup()<\/span><\/span><\/span>\u5728\u8bbe\u7f6e\u4e86<\/span>inet->rcv_saddr<\/span><\/span><\/span>\u5b57\u6bb5\u7684\u60c5\u51b5\u4e0b\uff0c\u4f1a\u5224\u65ad\u8be5\u5b57\u6bb5\u662f\u5426\u4e0e\u62a5\u6587\u76ee\u7684<\/span>IP<\/span><\/span><\/span>\u5730\u5740\u76f8\u540c\u3002<\/span><\/span><\/span>\n<\/p>\n

                            \n\tsys_bind()->inet_bind()->raw_bind()<\/span><\/span><\/span>\n<\/p>\n

                            \n\t<\/span><\/span><\/span>\n<\/p>\n

                            \n\tb)      <\/span><\/span><\/span>\u4fe1\u606f\u67e5\u770b<\/span><\/span><\/span>\n<\/p>\n

                            \n\t\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u7684\u4fe1\u606f\u53ef\u901a\u8fc7<\/span>\/proc\/net\/raw<\/span><\/span><\/span>\u8fdb\u884c\u67e5\u770b\u3002\u5982\u4e0b\u4e3a\u56fe<\/span>5<\/span><\/span><\/span>\u6240\u521b\u5efa\u7684<\/span>3<\/span><\/span><\/span>\u4e2a\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u7684\u4fe1\u606f\uff0c\u53ef\u4ee5\u67e5\u770b\u5230\u521b\u5efa\u5957\u63a5\u5b57\u65f6\u6307\u5b9a\u7684\u534f\u8bae\u7c7b\u578b\u3001\u7ed1\u5b9a\u7684\u5730\u5740\u3001\u53d1\u9001\u548c\u63a5\u6536\u961f\u5217\u5df2\u4f7f\u7528\u7684\u7f13\u5b58\u5927\u5c0f\u7b49\u4fe1\u606f\u3002<\/span><\/span><\/span>\u8fd9\u4e9b\u4fe1\u606f\u5bf9\u4e8e\u5206\u6790\u548c\u5b9a\u4f4d\u95ee\u9898\u6709\u5e2e\u52a9\u3002<\/span><\/span><\/span>\n<\/p>\n

                            \n
                            \n
                              \n
                            1. \n\t\t\t\tcat \/proc\/net\/raw\n\t\t\t<\/li>\n
                            2. \n\t\t\t\tsl local_address rem_address st tx_queue rx_queue tr tm->when retrnsmt uid timeout inode\n\t\t\t<\/li>\n
                            3. \n\t\t\t\t1: 00000000:0001 00000000:0000 07 00000000:00000000 00:00000000 00000000 0 0 1323 2 ffff8100070b2380\n\t\t\t<\/li>\n
                            4. \n\t\t\t\t6: 00000000:0006 00000000:0000 07 00000000:00000000 00:00000000 00000000 0 0 1322 2 ffff8100070b2080\n\t\t\t<\/li>\n
                            5. \n\t\t\t\t89: 00000000:0059 00000000:0000 07 00000000:00000000 00:00000000 00000000 0 0 1324 2 ffff8100070b2680\n\t\t\t<\/li>\n<\/ol><\/div>\n<\/div>\n

                              \n\t \n<\/p>\n

                              \n\t \u4e09\u3001\u5e94\u7528\u53ca\u6ce8\u610f\u4e8b\u9879<\/span><\/span><\/span> <\/span><\/span><\/span>\n<\/p>\n

                              3.1  \u4f7f\u7528<\/span><\/span><\/span><\/span>\u94fe\u8def\u5c42\u539f\u59cb\u5957\u63a5\u5b57<\/span><\/span><\/span> <\/span><\/span><\/span> <\/p>\n

                              \n\t<\/span><\/span><\/span>\n<\/p>\n

                              \n\t\u6ce8\u610f\u4e8b\u9879\uff1a<\/span> <\/span><\/b><\/span><\/span>\n<\/p>\n

                              \n\ta)       <\/span><\/span><\/span>\u5c3d\u91cf\u907f\u514d\u521b\u5efa\u8fc7\u591a\u539f\u59cb\u5957\u63a5\u5b57\uff0c\u4e14\u539f\u59cb\u5957\u63a5\u5b57\u8981\u5c3d\u91cf\u7ed1\u5b9a\u7f51\u5361\u3002\u56e0\u4e3a\u6536\u5230\u6bcf\u4e2a\u62a5\u6587\u9664\u4e86\u4f1a\u5c06\u5176\u5206\u53d1\u7ed9\u7ed1\u5b9a\u5728\u8be5\u7f51\u5361\u4e0a\u7684\u539f\u59cb\u5957\u63a5\u5b57\u5916\uff0c\u8fd8\u4f1a\u5206\u53d1\u7ed9\u6ca1\u6709\u7ed1\u5b9a\u7f51\u5361\u7684\u539f\u59cb\u5957\u63a5\u5b57\u3002\u5982\u679c\u539f\u59cb\u5957\u63a5\u5b57\u8f83\u591a\uff0c\u4e00\u4e2a\u62a5\u6587\u5c31\u4f1a\u5728\u8f6f\u4e2d\u65ad\u4e0a\u4e0b\u6587\u4e2d\u5206\u53d1\u591a\u6b21\uff0c\u9020\u6210\u5904\u7406\u65f6\u95f4\u8fc7\u957f\u3002<\/span><\/span><\/span>\n<\/p>\n

                              \n\t<\/span><\/span><\/span>\n<\/p>\n

                              \n\tb)      <\/span><\/span><\/span>\u53d1\u5305\u548c\u6536\u5305\u5c3d\u91cf\u4f7f\u7528\u540c\u4e00\u4e2a\u539f\u59cb\u5957\u63a5\u5b57\u3002\u5982\u679c\u53d1\u5305\u4e0e\u6536\u5305\u4f7f\u7528\u4e24\u4e2a\u4e0d\u540c\u7684\u539f\u59cb\u5957\u63a5\u5b57\uff0c\u4f1a\u7531\u4e8e\u63a5\u6536\u62a5\u6587\u65f6\u5206\u53d1\u591a\u6b21\u800c\u5f71\u54cd\u6027\u80fd\u3002\u800c\u4e14\u7528\u4e8e\u53d1\u9001\u7684\u90a3\u4e2a\u5957\u63a5\u5b57\u7684\u63a5\u6536\u961f\u5217\u4e0a\u4e5f\u4f1a\u7f13\u5b58\u62a5\u6587\uff0c\u76f4\u81f3\u8fbe\u5230\u63a5\u6536\u961f\u5217\u5927\u5c0f\u9650\u5236\uff0c\u4f1a\u9020\u6210\u5185\u5b58\u6cc4\u9732\u3002<\/span><\/span><\/span>\n<\/p>\n

                              \n\t<\/span><\/span><\/span>\n<\/p>\n

                              \n\tc)       <\/span><\/span><\/span>\u82e5\u53ea\u63a5\u6536\u6307\u5b9a\u7c7b\u578b\u4e8c\u5c42\u62a5\u6587\uff0c\u5728\u8c03\u7528<\/span>socket()<\/span><\/span><\/span>\u65f6\u6307\u5b9a\u7b2c\u4e09\u4e2a\u53c2\u6570\u7684\u534f\u8bae\u7c7b\u578b\uff0c\u800c\u6700\u597d\u4e0d\u8981\u4f7f\u7528<\/span>ETH_P_ALL<\/span><\/span><\/span>\u3002\u56e0\u4e3a<\/span>ETH_P_ALL<\/span><\/span><\/span>\u4f1a\u63a5\u6536\u6240\u6709\u7c7b\u578b\u7684\u62a5\u6587\uff0c\u800c\u4e14\u8fd8\u4f1a\u5c06\u5916\u53d1\u62a5\u6587\u6536\u56de\u6765\uff0c\u8fd9\u6837\u5c31\u9700\u8981\u505a<\/span>BPF<\/span><\/span><\/span>\u8fc7\u6ee4\uff0c\u6bd4\u8f83\u5f71\u54cd\u6027\u80fd\u3002<\/span><\/span><\/span>\n<\/p>\n

                              \n\t<\/span><\/span><\/span>\n<\/p>\n

                              \n\t<\/span><\/span><\/span> \n<\/p>\n

                              \n\t3.2  <\/span><\/span><\/span><\/span>\u4f7f\u7528\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57<\/span><\/span><\/span> <\/span><\/span><\/span>\n<\/p>\n

                              \n\t\u6ce8\u610f\u4e8b\u9879\uff1a<\/span> <\/span><\/b><\/span><\/span>\n<\/p>\n

                              \n\ta)       <\/span><\/span><\/span>\u7531\u4e8e<\/span>IP<\/span><\/span><\/span>\u62a5\u6587\u7684\u91cd\u7ec4\u662f\u5728\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u63a5\u6536\u6d41\u7a0b\u4e4b\u524d\u6267\u884c\u7684\uff0c\u6240\u4ee5\u8be5\u539f\u59cb\u5957\u63a5\u5b57\u4e0d\u80fd\u63a5\u6536\u5230<\/span>UDP<\/span><\/span><\/span>\u548c<\/span>TCP<\/span><\/span><\/span>\u7684\u5206\u7ec4\u6570\u636e\u3002<\/span><\/span><\/span>\n<\/p>\n

                              \n\t<\/span><\/span><\/span>\n<\/p>\n

                              \n\tb)      <\/span><\/span><\/span>\u82e5\u539f\u59cb\u5957\u63a5\u5b57\u5df2\u7531<\/span>bind()<\/span><\/span><\/span>\u7ed1\u5b9a\u4e86\u67d0\u4e2a\u672c\u5730<\/span>IP<\/span><\/span><\/span>\u5730\u5740\uff0c\u90a3\u4e48\u53ea\u6709\u76ee\u7684<\/span>IP<\/span><\/span><\/span>\u5730\u5740\u4e0e\u7ed1\u5b9a\u5730\u5740\u5339\u914d\u7684\u62a5\u6587\uff0c\u624d\u80fd\u9012\u9001\u5230\u8fd9\u4e2a\u5957\u63a5\u53e3\u4e0a\u3002<\/span><\/span><\/span>\n<\/p>\n

                              \n\t<\/span><\/span><\/span>\n<\/p>\n

                              \n\tc)       <\/span><\/span><\/span>\u82e5\u539f\u59cb\u5957\u63a5\u5b57\u5df2\u7531<\/span>connect()<\/span><\/span><\/span>\u6307\u5b9a\u4e86\u67d0\u4e2a\u8fdc\u5730<\/span>IP<\/span><\/span><\/span>\u5730\u5740\uff0c\u90a3\u4e48\u53ea\u6709\u6e90<\/span>IP<\/span><\/span><\/span>\u5730\u5740\u4e0e\u8fd9\u4e2a\u5df2\u8fde\u63a5\u5730\u5740\u5339\u914d\u7684\u62a5\u6587\uff0c\u624d\u80fd\u9012\u9001\u5230\u8fd9\u4e2a\u5957\u63a5\u53e3\u4e0a\u3002<\/span><\/span><\/span>\n<\/p>\n

                              \n\t<\/span><\/span><\/span>\n<\/p>\n

                              \n\t \n<\/p>\n

                              3.3  <\/span><\/span><\/span><\/span>\u7f51\u7edc\u8bca\u65ad\u5de5\u5177\u4f7f\u7528\u539f\u59cb\u5957\u63a5\u5b57<\/span><\/span><\/span> <\/span><\/span><\/span> <\/p>\n

                              \n\t\u5f88\u591a\u7f51\u7edc\u8bca\u65ad\u5de5\u5177\u4e5f\u662f\u5229\u7528\u539f\u59cb\u5957\u63a5\u5b57\u6765\u5b9e\u73b0\u7684\uff0c\u7ecf\u5e38\u4f1a\u4f7f\u7528\u5230\u7684\u6709<\/span>tcpdump, ping<\/span><\/span><\/span>\u548c<\/span>traceroute<\/span><\/span><\/span>\u7b49\u3002<\/span><\/span><\/span>\n<\/p>\n

                              \n\ttcpdump <\/span><\/b><\/span><\/span>\n<\/p>\n

                              \n\t\u8be5\u5de5\u5177\u7528\u4e8e\u622a\u83b7\u7f51\u53e3\u4e0a\u7684\u62a5\u6587\u6d41\u91cf\u3002\u5176\u5b9e\u73b0\u539f\u7406\u662f\u521b\u5efa<\/span>ETH_P_ALL<\/span><\/span><\/span>\u7c7b\u578b\u7684\u94fe\u8def\u5c42\u539f\u59cb\u5957\u63a5\u5b57\uff0c\u8bfb\u53d6\u548c\u89e3\u6790\u62a5\u6587\u6570\u636e\u5e76\u5c06\u4fe1\u606f\u663e\u793a\u51fa\u6765\u3002<\/span><\/span><\/span>\n<\/p>\n

                              \n\t<\/span><\/span><\/span>\n<\/p>\n

                              \n\tping <\/span><\/b><\/span><\/span>\n<\/p>\n

                              \n\t\u8be5\u5de5\u5177\u7528\u4e8e\u68c0\u67e5\u7f51\u7edc\u8fde\u63a5\u3002\u5176\u5b9e\u73b0\u539f\u7406\u662f\u521b\u5efa\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\uff0c\u6307\u5b9a\u534f\u8bae\u7c7b\u578b\u4e3a<\/span>IPPROTO_ICMP<\/span><\/span><\/span>\u3002\u68c0\u6d4b\u65b9\u6784\u9020<\/span>ICMP<\/span><\/span><\/span>\u56de\u5c04\u8bf7\u6c42\u62a5\u6587\uff08\u7c7b\u578b\u4e3a<\/span>ICMP_ECHO<\/span><\/span><\/span>\uff09\uff0c\u6839\u636e<\/span>ICMP<\/span><\/span><\/span>\u534f\u8bae\u5b9e\u73b0\uff0c\u88ab\u68c0\u6d4b\u65b9\u6536\u5230\u8be5\u8bf7\u6c42\u62a5\u6587\u540e\u4f1a\u54cd\u5e94\u4e00\u4e2a<\/span>ICMP<\/span><\/span><\/span>\u56de\u5c04\u5e94\u7b54\u62a5\u6587\uff08\u7c7b\u578b\u4e3a<\/span>ICMP_ECHOREPLY<\/span><\/span><\/span>\uff09\u3002\u7136\u540e\u68c0\u6d4b\u65b9\u901a\u8fc7\u539f\u59cb\u5957\u63a5\u5b57\u8bfb\u53d6\u5e76\u89e3\u6790\u5e94\u7b54\u62a5\u6587\uff0c\u5e76\u663e\u793a\u51fa\u5e8f\u53f7\u3001<\/span>TTL<\/span><\/span><\/span>\u7b49\u4fe1\u606f\u3002<\/span><\/span><\/span>\n<\/p>\n

                              \n\t<\/span><\/span><\/span>\n<\/p>\n

                              \n\ttraceroute <\/span><\/b><\/span><\/span>\n<\/p>\n

                              \n\t\u8be5\u5de5\u5177\u7528\u4e8e\u8ddf\u8e2a<\/span>IP<\/span><\/span><\/span>\u62a5\u6587\u5728\u7f51\u7edc\u4e2d\u7684\u8def\u7531\u8fc7\u7a0b\u3002\u5176\u5b9e\u73b0\u539f\u7406\u4e5f\u662f\u521b\u5efa\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\uff0c\u6307\u5b9a\u534f\u8bae\u7c7b\u578b\u4e3a<\/span>IPPROTO_ICMP<\/span><\/span><\/span>\u3002\u5047\u8bbe\u4ece<\/span>A<\/span><\/span><\/span>\u4e3b\u673a\u8def\u7531\u5230<\/span>D<\/span><\/span><\/span>\u4e3b\u673a\uff0c\u9700\u8981\u4f9d\u6b21\u7ecf\u8fc7<\/span>B<\/span><\/span><\/span>\u4e3b\u673a\u548c<\/span>C<\/span><\/span><\/span>\u4e3b\u673a\u3002\u4f7f\u7528<\/span>traceroute<\/span><\/span><\/span>\u6765\u8ddf\u8e2a<\/span>A<\/span><\/span><\/span>\u4e3b\u673a\u5230<\/span>D<\/span><\/span><\/span>\u4e3b\u673a\u7684\u8def\u7531\u9014\u5f84\uff0c\u5177\u4f53\u6b65\u9aa4\u5982\u4e0b\uff0c\u5728\u6bcf\u6b21\u63a2\u6d4b\u8fc7\u7a0b\u4e2d\u4f1a\u663e\u793a\u5404\u8282\u70b9\u7684<\/span>IP<\/span><\/span><\/span>\u3001\u65f6\u95f4\u7b49\u4fe1\u606f\u3002<\/span><\/span><\/span>\n<\/p>\n

                              \n\ta)       <\/span><\/span><\/span>A<\/span><\/span><\/span>\u4e3b\u673a\u4f7f\u7528\u666e\u901a\u7684<\/span>UDP<\/span><\/span><\/span>\u5957\u63a5\u5b57\u5411\u76ee\u7684\u4e3b\u673a\u53d1\u9001<\/span>TTL<\/span><\/span><\/span>\u4e3a<\/span>1<\/span><\/span><\/span>\uff08\u4f7f\u7528\u5957\u63a5\u53e3\u9009\u9879<\/span>IP_TTL<\/span><\/span><\/span>\u6765\u4fee\u6539\uff09\u7684<\/span>UDP<\/span><\/span><\/span>\u62a5\u6587\uff1b<\/span><\/span><\/span>\n<\/p>\n

                              \n\tb)      <\/span><\/span><\/span>B<\/span><\/span><\/span>\u4e3b\u673a\u6536\u5230\u8be5<\/span>UDP<\/span><\/span><\/span>\u62a5\u6587\u540e\uff0c\u7531\u4e8e<\/span>TTL<\/span><\/span><\/span>\u4e3a<\/span>1<\/span><\/span><\/span>\u4f1a\u62d2\u7edd\u8f6c\u53d1\uff0c\u5e76\u4e14\u5411<\/span>A<\/span><\/span><\/span>\u4e3b\u673a\u53d1\u9001<\/span>code<\/span><\/span><\/span>\u4e3a<\/span>ICMP_EXC_TTL<\/span><\/span><\/span>\u7684<\/span>ICMP<\/span><\/span><\/span>\u62a5\u6587\uff1b<\/span><\/span><\/span>\n<\/p>\n

                              \n\tc)       <\/span><\/span><\/span>A<\/span><\/span><\/span>\u4e3b\u673a\u7528\u521b\u5efa\u7684\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u8bfb\u53d6\u5e76\u89e3\u6790<\/span>ICMP<\/span><\/span><\/span>\u62a5\u6587\u3002\u5982\u679c<\/span>ICMP<\/span><\/span><\/span>\u62a5\u6587<\/span>code<\/span><\/span><\/span>\u662f<\/span>ICMP_EXC_TTL<\/span><\/span><\/span>\uff0c\u5c31\u5c06<\/span>UDP<\/span><\/span><\/span>\u62a5\u6587\u7684<\/span>TTL<\/span><\/span><\/span>\u589e\u52a0<\/span>1<\/span><\/span><\/span>\u5e76\u56de\u5230\u6b65\u9aa4<\/span>a)<\/span><\/span><\/span>\u7ee7\u7eed\u8fdb\u884c\u63a2\u6d4b\uff1b\u5982\u679c<\/span>ICMP<\/span><\/span><\/span>\u62a5\u6587\u7684<\/span>code<\/span><\/span><\/span>\u662f<\/span>ICMP_PROT_UNREACH<\/span><\/span><\/span>\uff0c\u8868\u793a<\/span>UDP<\/span><\/span><\/span>\u62a5\u6587\u5230\u8fbe\u4e86\u76ee\u7684\u5730\u3002<\/span><\/span><\/span>\n<\/p>\n

                              \n\t<\/span><\/span><\/span>\n<\/p>\n

                              \n\t       <\/span>       <\/span>A<\/span><\/span><\/span>\u4e3b\u673a\u2015<\/span>>B<\/span><\/span><\/span>\u4e3b\u673a\u2015<\/span>>C<\/span><\/span><\/span>\u4e3b\u673a\u2015<\/span>>D<\/span><\/span><\/span>\u4e3b\u673a<\/span><\/span><\/span>\n<\/p>\n

                              \n\t<\/span><\/span><\/span>\n<\/p>\n

                              \n\t<\/span><\/span><\/span> \n<\/p>\n

                              \n\t\u53c2\u8003\u8d44\u6599<\/span><\/span><\/span> <\/span><\/span><\/span>\n<\/p>\n

                              \n\t1.       <\/span><\/span><\/span>\u300a<\/span>Linux<\/span><\/span><\/span>\u5185\u6838\u6e90\u7801\u5256\u6790\u2014\u2014<\/span>TCP\/IP<\/span><\/span><\/span>\u5b9e\u73b0\u300b<\/span><\/span><\/span>\n<\/p>\n

                              \n\t2.       <\/span><\/span><\/span>\u300a\u6df1\u5165\u7406\u89e3<\/span>Linux<\/span><\/span><\/span>\u7f51\u7edc\u5185\u5e55\u300b<\/span><\/span><\/span>\n<\/p>\n

                              \n\t3.       <\/span><\/span><\/span>\u300a<\/span>UNIX<\/span><\/span><\/span>\u7f51\u7edc\u7f16\u7a0b<\/span> <\/span><\/span>\u7b2c<\/span>1<\/span><\/span><\/span>\u5377\uff1a\u5957\u63a5\u53e3<\/span>API<\/span><\/span><\/span>\u300b<\/span><\/span><\/span><\/p>\n<\/div><\/div>","protected":false},"excerpt":{"rendered":"

                              \n\thttp:\/\/blog.chinaunix.net\/uid-27074062-id-3388166.html<\/p>\n

                              \u672c\u6587\u4eceIPV4<\/span>\u534f\u8bae\u6808\u539f\u59cb\u5957\u63a5\u5b57\u7684\u5206\u7c7b\u5165\u624b\uff0c\u8be6\u7ec6\u4ecb\u7ecd\u4e86\u94fe\u8def\u5c42\u548c\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u7684\u7279\u70b9\u53ca\u5176\u5185\u6838\u5b9e\u73b0\u7ec6\u8282\u3002\u5e76\u7ed3\u5408\u539f\u59cb\u5957\u63a5\u5b57\u7684\u5b9e\u9645\u5e94\u7528\uff0c\u8bf4\u660e\u5404\u7c7b\u578b\u539f\u59cb\u5957\u63a5\u5b57\u7684\u9002\u5e94\u8303\u56f4\uff0c\u4ee5\u53ca\u5728\u5b9e\u9645\u4f7f\u7528\u65f6\u9700\u8981\u6ce8\u610f\u7684\u95ee\u9898\u3002<\/span><\/span><\/span>\u4e00\u3001\u539f\u59cb\u5957\u63a5\u5b57\u6982\u8ff0<\/span><\/span><\/span><\/p>\n

                              \u534f\u8bae\u6808\u7684\u539f\u59cb\u5957\u63a5\u5b57\u4ece\u5b9e\u73b0\u4e0a\u53ef\u4ee5\u5206\u4e3a\u201c\u94fe\u8def\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u201d\u548c\u201c\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u201d\u4e24…<\/span><\/span><\/span><\/span><\/span><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[324],"tags":[],"class_list":["post-88","post","type-post","status-publish","format-standard","hentry"],"yoast_head":"\nLinux\u539f\u59cb\u5957\u63a5\u5b57\u5b9e\u73b0\u5206\u6790 - Wayne's Blog<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"http:\/\/weizn.net\/?p=88\" \/>\n<meta property=\"og:locale\" content=\"zh_CN\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Linux\u539f\u59cb\u5957\u63a5\u5b57\u5b9e\u73b0\u5206\u6790 - Wayne's Blog\" \/>\n<meta property=\"og:description\" content=\"http:\/\/blog.chinaunix.net\/uid-27074062-id-3388166.html\u672c\u6587\u4eceIPV4\u534f\u8bae\u6808\u539f\u59cb\u5957\u63a5\u5b57\u7684\u5206\u7c7b\u5165\u624b\uff0c\u8be6\u7ec6\u4ecb\u7ecd\u4e86\u94fe\u8def\u5c42\u548c\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u7684\u7279\u70b9\u53ca\u5176\u5185\u6838\u5b9e\u73b0\u7ec6\u8282\u3002\u5e76\u7ed3\u5408\u539f\u59cb\u5957\u63a5\u5b57\u7684\u5b9e\u9645\u5e94\u7528\uff0c\u8bf4\u660e\u5404\u7c7b\u578b\u539f\u59cb\u5957\u63a5\u5b57\u7684\u9002\u5e94\u8303\u56f4\uff0c\u4ee5\u53ca\u5728\u5b9e\u9645\u4f7f\u7528\u65f6\u9700\u8981\u6ce8\u610f\u7684\u95ee\u9898\u3002\u4e00\u3001\u539f\u59cb\u5957\u63a5\u5b57\u6982\u8ff0\u534f\u8bae\u6808\u7684\u539f\u59cb\u5957\u63a5\u5b57\u4ece\u5b9e\u73b0\u4e0a\u53ef\u4ee5\u5206\u4e3a\u201c\u94fe\u8def\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u201d\u548c\u201c\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u201d\u4e24...\" \/>\n<meta property=\"og:url\" content=\"http:\/\/weizn.net\/?p=88\" \/>\n<meta property=\"og:site_name\" content=\"Wayne's Blog\" \/>\n<meta property=\"article:published_time\" content=\"2014-03-09T16:16:24+00:00\" \/>\n<meta property=\"og:image\" content=\"http:\/\/blog.chinaunix.net\/attachment\/201210\/27\/27074062_1351344679PO44.jpg\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"\u4f5c\u8005\" \/>\n\t<meta name=\"twitter:data1\" content=\"zinan\" \/>\n\t<meta name=\"twitter:label2\" content=\"\u9884\u8ba1\u9605\u8bfb\u65f6\u95f4\" \/>\n\t<meta name=\"twitter:data2\" content=\"9 \u5206\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"WebSite\",\"@id\":\"http:\/\/weizn.net\/#website\",\"url\":\"http:\/\/weizn.net\/\",\"name\":\"Wayne's Blog\",\"description\":\"\",\"publisher\":{\"@id\":\"http:\/\/weizn.net\/#\/schema\/person\/e88bc12c590502d8b6249326f960b264\"},\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"http:\/\/weizn.net\/?s={search_term_string}\"},\"query-input\":\"required name=search_term_string\"}],\"inLanguage\":\"zh-Hans\"},{\"@type\":\"ImageObject\",\"@id\":\"http:\/\/weizn.net\/?p=88#primaryimage\",\"inLanguage\":\"zh-Hans\",\"url\":\"http:\/\/blog.chinaunix.net\/attachment\/201210\/27\/27074062_1351344679PO44.jpg\",\"contentUrl\":\"http:\/\/blog.chinaunix.net\/attachment\/201210\/27\/27074062_1351344679PO44.jpg\"},{\"@type\":\"WebPage\",\"@id\":\"http:\/\/weizn.net\/?p=88#webpage\",\"url\":\"http:\/\/weizn.net\/?p=88\",\"name\":\"Linux\\u539f\\u59cb\\u5957\\u63a5\\u5b57\\u5b9e\\u73b0\\u5206\\u6790 - Wayne's Blog\",\"isPartOf\":{\"@id\":\"http:\/\/weizn.net\/#website\"},\"primaryImageOfPage\":{\"@id\":\"http:\/\/weizn.net\/?p=88#primaryimage\"},\"datePublished\":\"2014-03-09T16:16:24+00:00\",\"dateModified\":\"2014-03-09T16:16:24+00:00\",\"breadcrumb\":{\"@id\":\"http:\/\/weizn.net\/?p=88#breadcrumb\"},\"inLanguage\":\"zh-Hans\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"http:\/\/weizn.net\/?p=88\"]}]},{\"@type\":\"BreadcrumbList\",\"@id\":\"http:\/\/weizn.net\/?p=88#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"\\u9996\\u9875\",\"item\":\"http:\/\/weizn.net\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Linux\\u539f\\u59cb\\u5957\\u63a5\\u5b57\\u5b9e\\u73b0\\u5206\\u6790\"}]},{\"@type\":\"Article\",\"@id\":\"http:\/\/weizn.net\/?p=88#article\",\"isPartOf\":{\"@id\":\"http:\/\/weizn.net\/?p=88#webpage\"},\"author\":{\"@id\":\"http:\/\/weizn.net\/#\/schema\/person\/e88bc12c590502d8b6249326f960b264\"},\"headline\":\"Linux\\u539f\\u59cb\\u5957\\u63a5\\u5b57\\u5b9e\\u73b0\\u5206\\u6790\",\"datePublished\":\"2014-03-09T16:16:24+00:00\",\"dateModified\":\"2014-03-09T16:16:24+00:00\",\"mainEntityOfPage\":{\"@id\":\"http:\/\/weizn.net\/?p=88#webpage\"},\"wordCount\":1776,\"commentCount\":0,\"publisher\":{\"@id\":\"http:\/\/weizn.net\/#\/schema\/person\/e88bc12c590502d8b6249326f960b264\"},\"image\":{\"@id\":\"http:\/\/weizn.net\/?p=88#primaryimage\"},\"thumbnailUrl\":\"http:\/\/blog.chinaunix.net\/attachment\/201210\/27\/27074062_1351344679PO44.jpg\",\"articleSection\":[\"C\/C++\"],\"inLanguage\":\"zh-Hans\",\"potentialAction\":[{\"@type\":\"CommentAction\",\"name\":\"Comment\",\"target\":[\"http:\/\/weizn.net\/?p=88#respond\"]}]},{\"@type\":[\"Person\",\"Organization\"],\"@id\":\"http:\/\/weizn.net\/#\/schema\/person\/e88bc12c590502d8b6249326f960b264\",\"name\":\"zinan\",\"logo\":{\"@id\":\"http:\/\/weizn.net\/#personlogo\"}}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"Linux\u539f\u59cb\u5957\u63a5\u5b57\u5b9e\u73b0\u5206\u6790 - Wayne's Blog","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"http:\/\/weizn.net\/?p=88","og_locale":"zh_CN","og_type":"article","og_title":"Linux\u539f\u59cb\u5957\u63a5\u5b57\u5b9e\u73b0\u5206\u6790 - Wayne's Blog","og_description":"http:\/\/blog.chinaunix.net\/uid-27074062-id-3388166.html\u672c\u6587\u4eceIPV4\u534f\u8bae\u6808\u539f\u59cb\u5957\u63a5\u5b57\u7684\u5206\u7c7b\u5165\u624b\uff0c\u8be6\u7ec6\u4ecb\u7ecd\u4e86\u94fe\u8def\u5c42\u548c\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u7684\u7279\u70b9\u53ca\u5176\u5185\u6838\u5b9e\u73b0\u7ec6\u8282\u3002\u5e76\u7ed3\u5408\u539f\u59cb\u5957\u63a5\u5b57\u7684\u5b9e\u9645\u5e94\u7528\uff0c\u8bf4\u660e\u5404\u7c7b\u578b\u539f\u59cb\u5957\u63a5\u5b57\u7684\u9002\u5e94\u8303\u56f4\uff0c\u4ee5\u53ca\u5728\u5b9e\u9645\u4f7f\u7528\u65f6\u9700\u8981\u6ce8\u610f\u7684\u95ee\u9898\u3002\u4e00\u3001\u539f\u59cb\u5957\u63a5\u5b57\u6982\u8ff0\u534f\u8bae\u6808\u7684\u539f\u59cb\u5957\u63a5\u5b57\u4ece\u5b9e\u73b0\u4e0a\u53ef\u4ee5\u5206\u4e3a\u201c\u94fe\u8def\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u201d\u548c\u201c\u7f51\u7edc\u5c42\u539f\u59cb\u5957\u63a5\u5b57\u201d\u4e24...","og_url":"http:\/\/weizn.net\/?p=88","og_site_name":"Wayne's Blog","article_published_time":"2014-03-09T16:16:24+00:00","og_image":[{"url":"http:\/\/blog.chinaunix.net\/attachment\/201210\/27\/27074062_1351344679PO44.jpg"}],"twitter_card":"summary_large_image","twitter_misc":{"\u4f5c\u8005":"zinan","\u9884\u8ba1\u9605\u8bfb\u65f6\u95f4":"9 \u5206"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebSite","@id":"http:\/\/weizn.net\/#website","url":"http:\/\/weizn.net\/","name":"Wayne's Blog","description":"","publisher":{"@id":"http:\/\/weizn.net\/#\/schema\/person\/e88bc12c590502d8b6249326f960b264"},"potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"http:\/\/weizn.net\/?s={search_term_string}"},"query-input":"required name=search_term_string"}],"inLanguage":"zh-Hans"},{"@type":"ImageObject","@id":"http:\/\/weizn.net\/?p=88#primaryimage","inLanguage":"zh-Hans","url":"http:\/\/blog.chinaunix.net\/attachment\/201210\/27\/27074062_1351344679PO44.jpg","contentUrl":"http:\/\/blog.chinaunix.net\/attachment\/201210\/27\/27074062_1351344679PO44.jpg"},{"@type":"WebPage","@id":"http:\/\/weizn.net\/?p=88#webpage","url":"http:\/\/weizn.net\/?p=88","name":"Linux\u539f\u59cb\u5957\u63a5\u5b57\u5b9e\u73b0\u5206\u6790 - Wayne's Blog","isPartOf":{"@id":"http:\/\/weizn.net\/#website"},"primaryImageOfPage":{"@id":"http:\/\/weizn.net\/?p=88#primaryimage"},"datePublished":"2014-03-09T16:16:24+00:00","dateModified":"2014-03-09T16:16:24+00:00","breadcrumb":{"@id":"http:\/\/weizn.net\/?p=88#breadcrumb"},"inLanguage":"zh-Hans","potentialAction":[{"@type":"ReadAction","target":["http:\/\/weizn.net\/?p=88"]}]},{"@type":"BreadcrumbList","@id":"http:\/\/weizn.net\/?p=88#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"\u9996\u9875","item":"http:\/\/weizn.net\/"},{"@type":"ListItem","position":2,"name":"Linux\u539f\u59cb\u5957\u63a5\u5b57\u5b9e\u73b0\u5206\u6790"}]},{"@type":"Article","@id":"http:\/\/weizn.net\/?p=88#article","isPartOf":{"@id":"http:\/\/weizn.net\/?p=88#webpage"},"author":{"@id":"http:\/\/weizn.net\/#\/schema\/person\/e88bc12c590502d8b6249326f960b264"},"headline":"Linux\u539f\u59cb\u5957\u63a5\u5b57\u5b9e\u73b0\u5206\u6790","datePublished":"2014-03-09T16:16:24+00:00","dateModified":"2014-03-09T16:16:24+00:00","mainEntityOfPage":{"@id":"http:\/\/weizn.net\/?p=88#webpage"},"wordCount":1776,"commentCount":0,"publisher":{"@id":"http:\/\/weizn.net\/#\/schema\/person\/e88bc12c590502d8b6249326f960b264"},"image":{"@id":"http:\/\/weizn.net\/?p=88#primaryimage"},"thumbnailUrl":"http:\/\/blog.chinaunix.net\/attachment\/201210\/27\/27074062_1351344679PO44.jpg","articleSection":["C\/C++"],"inLanguage":"zh-Hans","potentialAction":[{"@type":"CommentAction","name":"Comment","target":["http:\/\/weizn.net\/?p=88#respond"]}]},{"@type":["Person","Organization"],"@id":"http:\/\/weizn.net\/#\/schema\/person\/e88bc12c590502d8b6249326f960b264","name":"zinan","logo":{"@id":"http:\/\/weizn.net\/#personlogo"}}]}},"_links":{"self":[{"href":"http:\/\/weizn.net\/index.php?rest_route=\/wp\/v2\/posts\/88","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/weizn.net\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/weizn.net\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/weizn.net\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/weizn.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=88"}],"version-history":[{"count":0,"href":"http:\/\/weizn.net\/index.php?rest_route=\/wp\/v2\/posts\/88\/revisions"}],"wp:attachment":[{"href":"http:\/\/weizn.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=88"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/weizn.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=88"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/weizn.net\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=88"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}