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pirog-spb
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| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,120 @@ | ||
| package utils | ||
|
|
||
| import ( | ||
| "encoding/binary" | ||
| "fmt" | ||
| "os" | ||
| "runtime" | ||
|
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||
| "github.com/google/gopacket/layers" | ||
| "github.com/google/gopacket/pcapgo" | ||
|
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| "github.com/cilium/ebpf" | ||
| "github.com/cilium/ebpf/perf" | ||
| "github.com/google/gopacket" | ||
| "github.com/rs/zerolog/log" | ||
| ) | ||
|
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| type PacketDumper struct { | ||
| praceMap *ebpf.Map | ||
| f *os.File | ||
| w *pcapgo.NgWriter | ||
| } | ||
|
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| func NewPacketDumper(dumpPath string, praceMap *ebpf.Map) (*PacketDumper, error) { | ||
|
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| f, _ := os.Create(dumpPath) | ||
|
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| //w := pcapgo.NewWriterNanos(f) | ||
| //_ = w.WriteFileHeader(65536, layers.LinkTypeEthernet) // new file, must do this. | ||
| w, err := pcapgo.NewNgWriter(f, layers.LinkTypeEthernet) | ||
| if err != nil { | ||
| f.Close() | ||
| return nil, fmt.Errorf("can't create ng pcap writer: %s", err.Error()) | ||
| } | ||
|
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| _, err = w.AddInterface(pcapgo.NgInterface{ | ||
| Name: "in", | ||
| OS: runtime.GOOS, | ||
| SnapLength: 0, //unlimited | ||
| TimestampResolution: 9, | ||
| LinkType: layers.LinkTypeEthernet}) | ||
| if err != nil { | ||
| f.Close() | ||
| return nil, fmt.Errorf("can't add in ng pcap interface:: %s", err.Error()) | ||
| } | ||
|
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||
| _, err = w.AddInterface(pcapgo.NgInterface{ | ||
| Name: "out", | ||
| OS: runtime.GOOS, | ||
| SnapLength: 0, //unlimited | ||
| TimestampResolution: 9, | ||
| LinkType: layers.LinkTypeEthernet}) | ||
| if err != nil { | ||
| f.Close() | ||
| return nil, fmt.Errorf("can't add out ng pcap interface:: %s", err.Error()) | ||
| } | ||
|
|
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| return &PacketDumper{ | ||
| praceMap: praceMap, | ||
| f: f, | ||
| w: w, | ||
| }, nil | ||
| } | ||
|
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| func (dumper *PacketDumper) Run() { | ||
|
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| rd, err := perf.NewReader(dumper.praceMap, 4096) | ||
| if err != nil { | ||
| log.Error().Msgf(" can't create perf reader: %s", err.Error()) | ||
| return | ||
| } | ||
| defer rd.Close() | ||
|
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| var rec perf.Record | ||
| for { | ||
| if err := rd.ReadInto(&rec); err != nil { | ||
| log.Error().Msgf(" can't read from perf map: %s", err.Error()) | ||
| return | ||
| } | ||
|
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| if rec.LostSamples > 0 { | ||
| log.Warn().Msgf(" lost samples from perf map: %d", rec.LostSamples) | ||
| } | ||
|
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| sampleLength := len(rec.RawSample) | ||
| if sampleLength < 9 { | ||
| log.Error().Msgf(" perf sample too small: %d", sampleLength) | ||
| } | ||
|
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| magic := binary.LittleEndian.Uint16(rec.RawSample[:2]) | ||
| if magic != 0xdead { | ||
| continue | ||
| } | ||
|
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| packetLength := binary.LittleEndian.Uint16(rec.RawSample[2:4]) | ||
| packetIface := binary.LittleEndian.Uint32(rec.RawSample[4:8]) + 1 | ||
| packet := rec.RawSample[8 : 8+packetLength] | ||
|
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| //pack := gopacket.NewPacket(packet, layers.LayerTypeEthernet, gopacket.Default) | ||
| //log.Trace().Msgf("Sample lost=%d, remaining=%d, len=%d, packet: %s", rec.LostSamples, rec.Remaining, packetLength, pack.Dump()) | ||
|
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| if err := dumper.w.WritePacket(gopacket.CaptureInfo{ | ||
| Length: int(packetLength), | ||
| CaptureLength: int(packetLength), | ||
| InterfaceIndex: int(packetIface), | ||
| }, packet); err != nil { | ||
| log.Error().Msgf(" can't write perf sample to pcap dump: %s", err.Error()) | ||
| } | ||
| } | ||
| } | ||
|
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| func (dumper *PacketDumper) Close() { | ||
| if dumper.w != nil { | ||
| dumper.w.Flush() | ||
| } | ||
|
|
||
| if dumper.f != nil { | ||
| dumper.f.Close() | ||
| } | ||
| } |