{"id":207450,"date":"2025-07-08T12:11:22","date_gmt":"2025-07-08T04:11:22","guid":{"rendered":"https:\/\/server.hk\/cnblog\/207450\/"},"modified":"2025-07-08T12:11:22","modified_gmt":"2025-07-08T04:11:22","slug":"%e6%97%a0%e6%b3%95%e4%bd%bf%e7%94%a8-gopacket-%e7%9b%91%e5%90%ac%e8%bf%9e%e6%8e%a5%e7%9a%84%e5%a5%97%e6%8e%a5%e5%ad%97","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/207450\/","title":{"rendered":"\u65e0\u6cd5\u4f7f\u7528 gopacket \u76d1\u542c\u8fde\u63a5\u7684\u5957\u63a5\u5b57"},"content":{"rendered":"

<\/b> <\/p>\n

\u5f53\u524d\u4f4d\u7f6e\uff1a ><\/span> ><\/span> ><\/span> ><\/span> \u65e0\u6cd5\u4f7f\u7528 gopacket \u76d1\u542c\u8fde\u63a5\u7684\u5957\u63a5\u5b57<\/span><\/p>\n

\u6765\u6e90\uff1astackoverflow<\/span>
\n2024-04-22 18:09:36<\/span>
\n<\/i>0\u6d4f\u89c8<\/span>
\n<\/i>\u6536\u85cf<\/span> <\/p>\n

\u672c\u7bc7\u6587\u7ae0\u5411\u5927\u5bb6\u4ecb\u7ecd\u300a\u65e0\u6cd5\u4f7f\u7528 gopacket \u76d1\u542c\u8fde\u63a5\u7684\u5957\u63a5\u5b57\u300b\uff0c\u4e3b\u8981\u5305\u62ec\uff0c\u5177\u6709\u4e00\u5b9a\u7684\u53c2\u8003\u4ef7\u503c\uff0c\u9700\u8981\u7684\u670b\u53cb\u53ef\u4ee5\u53c2\u8003\u4e00\u4e0b\u3002<\/p>\n

\u95ee\u9898\u5185\u5bb9
\n <\/p>\n

\u6211\u6b63\u5728\u5c1d\u8bd5\u4f7f\u7528 gopacket \u6765\u76d1\u542c\u5957\u63a5\u5b57\u5e76\u6253\u5370 tcp \u6570\u636e\u5305\u6709\u6548\u8d1f\u8f7d\u3002\u5982\u679c\u6211\u5148\u542f\u52a8 snooper \u5e94\u7528\u7a0b\u5e8f\uff0c\u7136\u540e\u8fde\u63a5 tcp \u5957\u63a5\u5b57\uff0c\u5219\u4e00\u5207\u6b63\u5e38\u3002\u5982\u679c snooper \u5e94\u7528\u7a0b\u5e8f\u542f\u52a8\u65f6\u5957\u63a5\u5b57\u5df2\u8fde\u63a5\uff0c\u5219\u4e0d\u4f1a\u6253\u5370\u4efb\u4f55\u5185\u5bb9\u3002<\/p>\n

\u5982\u679c\u6211\u4f20\u9012\u6b64\u9009\u9879 – assembly_debug_log\uff0c\u6211\u4f1a\u5f97\u5230\u4ee5\u4e0b\u8f93\u51fa\uff1a<\/p>\n

2022\/04\/22 11:36:10 assembly.go:582: [127.0.0.1->127.0.0.1 43584->80] waiting for start, storing into connection\n2022\/04\/22 11:36:10 assembly.go:582: [127.0.0.1->127.0.0.1 80->43584] waiting for start, storing into connection\n2022\/04\/22 11:36:10 assembly.go:537: ignoring useless packet\n2022\/04\/22 11:36:12 assembly.go:582: [127.0.0.1->127.0.0.1 43584->80] waiting for start, storing into connection\n2022\/04\/22 11:36:12 assembly.go:582: [127.0.0.1->127.0.0.1 80->43584] waiting for start, storing into connection\n2022\/04\/22 11:36:12 assembly.go:537: ignoring useless packet<\/pre>\n
\u8be5\u8c03\u8bd5\u6d88\u606f\u4f4d\u4e8e assembly.go \u4e2d\u7684\u201cif\u201d\u4e0b\u65b9\uff1a<\/p>\n
if conn.nextseq == invalidsequence<\/pre>\n
\u6211\u6ca1\u6709\u770b\u5230\u4efb\u4f55\u65b9\u6cd5\u6765\u8bbe\u7f6e conn.nextseq \u7684\u503c\u3002<\/p>\n
\u56e0\u6b64\uff0c\u8be5\u6c47\u7f16\u7a0b\u5e8f\u5c06\u9690\u85cf\u6570\u636e\u5305\uff0c\u76f4\u5230\u6536\u5230 syn \u6570\u636e\u5305\u4e3a\u6b62\uff0c\u4f46\u7531\u4e8e\u8fde\u63a5\u5df2\u7ecf\u5efa\u7acb\uff0c\u56e0\u6b64\u4e0d\u4f1a\u8fd9\u6837\u505a\u3002<\/p>\n
\u6709\u6ca1\u6709\u529e\u6cd5\u4ece\u5df2\u7ecf\u5efa\u7acb\u7684\u5957\u63a5\u5b57\u8fde\u63a5\u6253\u5370 tcp \u6570\u636e\u5305\uff1f<\/p>\n
\u8fd9\u662f\u4ee3\u7801\uff1a<\/p>\n
package main\n\nimport (\n    \"io\"\n    \"log\"\n\n    \"github.com\/google\/gopacket\"\n    \"github.com\/google\/gopacket\/examples\/util\"\n    \"github.com\/google\/gopacket\/layers\"\n    \"github.com\/google\/gopacket\/pcap\"\n    \"github.com\/google\/gopacket\/tcpassembly\"\n    \"github.com\/google\/gopacket\/tcpassembly\/tcpreader\"\n)\n\ntype myStream struct {\n    r tcpreader.ReaderStream\n}\n\nfunc (ms *myStream) run() {\n    buf := make([]byte, 4096)\n    for {\n        n, err := ms.r.Read(buf)\n        if err == io.EOF {\n            return\n        } else if err != nil {\n            log.Fatal(err)\n        }\n        log.Println(string(buf[:n]))\n    }\n}\n\ntype myStreamFactory struct{}\n\nfunc (msf *myStreamFactory) New(_, _ gopacket.Flow) tcpassembly.Stream {\n    stream := &myStream{tcpreader.NewReaderStream()}\n    go stream.run()\n    return &stream.r\n}\n\nfunc main() {\n    defer util.Run()()\n\n    flags := log.Flags()\n    log.SetFlags(flags | log.Lshortfile)\n\n    handle, err := pcap.OpenLive(\"lo\", 262144, true, pcap.BlockForever)\n    if err != nil {\n        log.Fatal(err)\n    }\n\n    if err = handle.SetBPFFilter(\"tcp and port 80\"); err != nil {\n        log.Fatal(err)\n    }\n\n    streamFactory := &myStreamFactory{}\n    streamPool := tcpassembly.NewStreamPool(streamFactory)\n    assembler := tcpassembly.NewAssembler(streamPool)\n\n    packetSource := gopacket.NewPacketSource(handle, handle.LinkType())\n    for packet := range packetSource.Packets() {\n        if packet.NetworkLayer() == nil || packet.TransportLayer() == nil || packet.TransportLayer().LayerType() != layers.LayerTypeTCP {\n            log.Println(\"Unusable packet\")\n            continue\n        }\n        tcp := packet.TransportLayer().(*layers.TCP)\n        assembler.AssembleWithTimestamp(packet.NetworkLayer().NetworkFlow(), tcp, packet.Metadata().Timestamp)\n    }\n}<\/pre>\n
 <\/p>\n
\u6b63\u786e\u7b54\u6848<\/h2>\n
 <\/p>\n
\u521b\u5efa\u65b0\u6d41\u540e\uff0c\u6211\u6dfb\u52a0\u4e86\u5bf9 assembler.flushwithoptions<\/code> \u7684\u8c03\u7528\uff0c\u73b0\u5728\u4f3c\u4e4e\u5de5\u4f5c\u6b63\u5e38\u3002<\/p>\n
package main\n\nimport (\n    \"io\"\n    \"log\"\n    \"time\"\n\n    \"github.com\/google\/gopacket\"\n    \"github.com\/google\/gopacket\/examples\/util\"\n    \"github.com\/google\/gopacket\/layers\"\n    \"github.com\/google\/gopacket\/pcap\"\n    \"github.com\/google\/gopacket\/tcpassembly\"\n    \"github.com\/google\/gopacket\/tcpassembly\/tcpreader\"\n)\n\ntype myStream struct {\n    r tcpreader.ReaderStream\n}\n\nfunc (ms *myStream) run() {\n    buf := make([]byte, 4096)\n    for {\n        n, err := ms.r.Read(buf)\n        if err == io.EOF {\n            return\n        } else if err != nil {\n            log.Fatal(err)\n        }\n        log.Println(string(buf[:n]))\n    }\n}\n\ntype myStreamFactory struct {\n    iWantFlush bool\n}\n\nfunc (msf *myStreamFactory) New(_, _ gopacket.Flow) tcpassembly.Stream {\n    stream := &myStream{tcpreader.NewReaderStream()}\n    go stream.run()\n    msf.iWantFlush = true\n    return &stream.r\n}\n\nfunc main() {\n    defer util.Run()()\n\n    flags := log.Flags()\n    log.SetFlags(flags | log.Lshortfile)\n\n    handle, err := pcap.OpenLive(\"lo\", 262144, true, pcap.BlockForever)\n    if err != nil {\n        log.Fatal(err)\n    }\n\n    if err = handle.SetBPFFilter(\"tcp and port 80\"); err != nil {\n        log.Fatal(err)\n    }\n\n    streamFactory := &myStreamFactory{}\n    streamPool := tcpassembly.NewStreamPool(streamFactory)\n    assembler := tcpassembly.NewAssembler(streamPool)\n\n    packetSource := gopacket.NewPacketSource(handle, handle.LinkType())\n    for packet := range packetSource.Packets() {\n        if packet.NetworkLayer() == nil || packet.TransportLayer() == nil || packet.TransportLayer().LayerType() != layers.LayerTypeTCP {\n            log.Println(\"Unusable packet\")\n            continue\n        }\n        tcp := packet.TransportLayer().(*layers.TCP)\n        assembler.AssembleWithTimestamp(packet.NetworkLayer().NetworkFlow(), tcp, packet.Metadata().Timestamp)\n        if streamFactory.iWantFlush {\n            assembler.FlushWithOptions(tcpassembly.FlushOptions{time.Now(), false})\n            streamFactory.iWantFlush = false\n        }\n    }\n}<\/pre>\n
\u5230\u8fd9\u91cc\uff0c\u6211\u4eec\u4e5f\u5c31\u8bb2\u5b8c\u4e86\u300a\u65e0\u6cd5\u4f7f\u7528 gopacket \u76d1\u542c\u8fde\u63a5\u7684\u5957\u63a5\u5b57\u300b\u7684\u5185\u5bb9\u4e86\u3002\u4e2a\u4eba\u8ba4\u4e3a\uff0c\u57fa\u7840\u77e5\u8bc6\u7684\u5b66\u4e60\u548c\u5de9\u56fa\uff0c\u662f\u4e3a\u4e86\u66f4\u597d\u7684\u5c06\u5176\u8fd0\u7528\u5230\u9879\u76ee\u4e2d\uff0c\u6b22\u8fce\u5173\u6ce8\u516c\u4f17\u53f7\uff0c\u5e26\u4f60\u4e86\u89e3\u66f4\u591a\u5173\u4e8e\u7684\u77e5\u8bc6\u70b9\uff01<\/p>\n","protected":false},"excerpt":{"rendered":"
\u5f53\u524d\u4f4d\u7f6e\uff1a > > ...<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4925],"tags":[],"class_list":["post-207450","post","type-post","status-publish","format-standard","hentry","category-4925"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/207450","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/comments?post=207450"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/207450\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=207450"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=207450"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=207450"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}