-
Notifications
You must be signed in to change notification settings - Fork 0
/
pcap.go
97 lines (81 loc) · 2.15 KB
/
pcap.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
package main
import (
"fmt"
"io"
"runtime"
"time"
"github.com/google/gopacket"
"github.com/google/gopacket/pcapgo"
)
type PcapWriter struct {
listenIf int
firstIf int
secondIf int
pcapWriter *pcapgo.NgWriter
}
func (p *PcapWriter) WritePacket(req, resp1, resp2 []byte) error {
if err := p.pcapWriter.WritePacket(gopacket.CaptureInfo{
Timestamp: time.Now(),
CaptureLength: len(req),
Length: len(req),
InterfaceIndex: p.listenIf,
}, req); err != nil {
return fmt.Errorf("unable to write req packet: %w", err)
}
if err := p.pcapWriter.WritePacket(gopacket.CaptureInfo{
Timestamp: time.Now(),
CaptureLength: len(resp1),
Length: len(resp1),
InterfaceIndex: p.firstIf,
}, resp1); err != nil {
return fmt.Errorf("unable to write first reply packet: %w", err)
}
if err := p.pcapWriter.WritePacket(gopacket.CaptureInfo{
Timestamp: time.Now(),
CaptureLength: len(resp2),
Length: len(resp2),
InterfaceIndex: p.secondIf,
}, resp2); err != nil {
return fmt.Errorf("unable to write second reply packet: %w", err)
}
return nil
}
func (p *PcapWriter) Flush() error {
return p.pcapWriter.Flush()
}
func (p *PcapWriter) Close() error {
if err := p.pcapWriter.Flush(); err != nil {
return fmt.Errorf("unable to flush pcap file: %w", err)
}
return nil
}
func NewPcapWriter(w io.Writer) (*PcapWriter, error) {
pcapWriter, err := pcapgo.NewNgWriter(w, 147) // DLT_USER0
if err != nil {
return nil, fmt.Errorf("unable to open pcap ng writer: %w", err)
}
listenIf, err := pcapWriter.AddInterface(pcapgo.NgInterface{
Name: cli.ListenAddr,
Comment: "listen address",
OS: runtime.GOOS,
LinkType: 147,
})
firstIf, err := pcapWriter.AddInterface(pcapgo.NgInterface{
Name: cli.FirstRemoteAddr,
Comment: "first remote address",
OS: runtime.GOOS,
LinkType: 147,
})
secondIf, err := pcapWriter.AddInterface(pcapgo.NgInterface{
Name: cli.SecondRemoteAddr,
Comment: "second remote address",
OS: runtime.GOOS,
LinkType: 147,
})
return &PcapWriter{
listenIf: listenIf,
firstIf: firstIf,
secondIf: secondIf,
pcapWriter: pcapWriter,
}, nil
}