cloudflared-mirror/vendor/github.com/google/gopacket/layers/fuzz_layer.go

40 lines
1.2 KiB
Go

// Copyright 2019 The GoPacket Authors. All rights reserved.
//
// Use of this source code is governed by a BSD-style license that can be found
// in the LICENSE file in the root of the source tree.
package layers
import (
"encoding/binary"
"github.com/google/gopacket"
)
// FuzzLayer is a fuzz target for the layers package of gopacket
// A fuzz target is a function processing a binary blob (byte slice)
// The process here is to interpret this data as a packet, and print the layers contents.
// The decoding options and the starting layer are encoded in the first bytes.
// The function returns 1 if this is a valid packet (no error layer)
func FuzzLayer(data []byte) int {
if len(data) < 3 {
return 0
}
// use the first two bytes to choose the top level layer
startLayer := binary.BigEndian.Uint16(data[:2])
var fuzzOpts = gopacket.DecodeOptions{
Lazy: data[2]&0x1 != 0,
NoCopy: data[2]&0x2 != 0,
SkipDecodeRecovery: data[2]&0x4 != 0,
DecodeStreamsAsDatagrams: data[2]&0x8 != 0,
}
p := gopacket.NewPacket(data[3:], gopacket.LayerType(startLayer), fuzzOpts)
for _, l := range p.Layers() {
gopacket.LayerString(l)
}
if p.ErrorLayer() != nil {
return 0
}
return 1
}