-
Notifications
You must be signed in to change notification settings - Fork 159
/
pcapUtils.go
155 lines (126 loc) · 4.16 KB
/
pcapUtils.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
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
/*
* NETCAP - Traffic Analysis Framework
* Copyright (c) 2017 Philipp Mieden <dreadl0ck [at] protonmail [dot] ch>
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
package collector
import (
"bufio"
"os"
"path/filepath"
"github.com/dreadl0ck/netcap/encoder"
"github.com/google/gopacket"
"github.com/google/gopacket/layers"
"github.com/google/gopacket/pcapgo"
"github.com/pkg/errors"
)
// close errors.pcap and unknown.pcap
func (c *Collector) closePcapFiles() error {
// unknown.pcap
err := c.unkownPcapWriterBuffered.Flush()
if err != nil {
return err
}
i, err := c.unknownPcapFile.Stat()
if err != nil {
return err
}
// if file is empty, or a pcap with just the header
if i.Size() == 0 || i.Size() == 24 {
//println("removing", fd.Name())
err := os.Remove(c.unknownPcapFile.Name())
if err != nil {
return errors.Wrap(err, "failed to remove file: "+c.unknownPcapFile.Name())
}
}
if err := c.unknownPcapFile.Sync(); err != nil {
return err
}
if err := c.unknownPcapFile.Close(); err != nil {
return err
}
// errors.pcap
if err := c.errorsPcapWriterBuffered.Flush(); err != nil {
return err
}
i, err = c.errorsPcapFile.Stat()
if err != nil {
return err
}
// if file is empty, or a pcap with just the header
if i.Size() == 0 || i.Size() == 24 {
//println("removing", fd.Name())
if err := os.Remove(c.errorsPcapFile.Name()); err != nil {
return err
}
}
if err := c.errorsPcapFile.Sync(); err != nil {
return err
}
if err := c.errorsPcapFile.Close(); err != nil {
return err
}
return nil
}
// create unknown.pcap file for packets with unknown layers.
func (c *Collector) createUnknownPcap() error {
var err error
// Open output pcap file and write header
c.unknownPcapFile, err = os.Create(filepath.Join(c.config.EncoderConfig.Out, "unknown.pcap"))
if err != nil {
return err
}
c.unkownPcapWriterBuffered = bufio.NewWriterSize(c.unknownPcapFile, encoder.BlockSize)
pcapWriter := pcapgo.NewWriter(c.unkownPcapWriterBuffered)
// set global pcap writer
c.unkownPcapWriterAtomic = NewAtomicPcapGoWriter(pcapWriter)
if err := pcapWriter.WriteFileHeader(1024, layers.LinkTypeEthernet); err != nil {
return err
}
return nil
}
// create errors.pcap file for errors
func (c *Collector) createErrorsPcap() error {
var err error
// Open output pcap file and write header
c.errorsPcapFile, err = os.Create(filepath.Join(c.config.EncoderConfig.Out, "errors.pcap"))
if err != nil {
return err
}
c.errorsPcapWriterBuffered = bufio.NewWriterSize(c.errorsPcapFile, encoder.BlockSize)
pcapWriter := pcapgo.NewWriter(c.errorsPcapWriterBuffered)
// set global pcap writer
c.errorsPcapWriterAtomic = NewAtomicPcapGoWriter(pcapWriter)
if err := pcapWriter.WriteFileHeader(1024, layers.LinkTypeEthernet); err != nil {
return err
}
return nil
}
// writePacketToUnknownPcap writse a packet to the unknown.pcap file
// if WriteUnknownPackets is set in the config.
func (c *Collector) writePacketToUnknownPcap(p gopacket.Packet) error {
if c.config.WriteUnknownPackets {
return c.unkownPcapWriterAtomic.WritePacket(p.Metadata().CaptureInfo, p.Data())
}
return nil
}
// logPacketError handles an error when decoding a packet.
func (c *Collector) logPacketError(p gopacket.Packet, err string) error {
// increment errorMap stats
c.errorMap.Inc(err)
// write entry to errors.log
c.errorLogFile.WriteString(p.Metadata().Timestamp.String() + "\nError: " + err + "\nPacket:\n" + p.Dump() + "\n")
// write packet to errors.pcap
return c.writePacketToErrorsPcap(p)
}
// writePacketToErrorsPcap writes a packet to the errors.pcap file.
func (c *Collector) writePacketToErrorsPcap(p gopacket.Packet) error {
return c.errorsPcapWriterAtomic.WritePacket(p.Metadata().CaptureInfo, p.Data())
}