Golang gopacket.PacketBuilder類代碼示例

func decodeSCTPEmptyLayer(data []byte, p gopacket.PacketBuilder) error {
	sc := &SCTPEmptyLayer{
		SCTPChunk: decodeSCTPChunk(data),
	}
	p.AddLayer(sc)
	return p.NextDecoder(gopacket.DecodeFunc(decodeWithSCTPChunkTypePrefix))
}

func decodeSCTPCookieEcho(data []byte, p gopacket.PacketBuilder) error {
	sc := &SCTPCookieEcho{
		SCTPChunk: decodeSCTPChunk(data),
	}
	sc.Cookie = data[4:sc.Length]
	p.AddLayer(sc)
	return p.NextDecoder(gopacket.DecodeFunc(decodeWithSCTPChunkTypePrefix))
}

func decodeSCTPShutdown(data []byte, p gopacket.PacketBuilder) error {
	sc := &SCTPShutdown{
		SCTPChunk:        decodeSCTPChunk(data),
		CumulativeTSNAck: binary.BigEndian.Uint32(data[4:8]),
	}
	p.AddLayer(sc)
	return p.NextDecoder(gopacket.DecodeFunc(decodeWithSCTPChunkTypePrefix))
}

func decodeIPv6HopByHop(data []byte, p gopacket.PacketBuilder) error {
	i := &IPv6HopByHop{}
	err := i.DecodeFromBytes(data, p)
	p.AddLayer(i)
	if err != nil {
		return err
	}
	return p.NextDecoder(i.NextHeader)
}

func decodeICMPv4(data []byte, p gopacket.PacketBuilder) error {
	i := &ICMPv4{}
	err := i.DecodeFromBytes(data, p)
	if err != nil {
		return err
	}
	p.AddLayer(i)
	return p.NextDecoder(gopacket.LayerTypePayload)
}

func decodeIPSecESP(data []byte, p gopacket.PacketBuilder) error {
	i := &IPSecESP{
		BaseLayer: BaseLayer{data, nil},
		SPI:       binary.BigEndian.Uint32(data[:4]),
		Seq:       binary.BigEndian.Uint32(data[4:8]),
		Encrypted: data[8:],
	}
	p.AddLayer(i)
	return nil
}

// decodeDNS decodes the byte slice into a DNS type. It also
// setups the application Layer in PacketBuilder.
func decodeDNS(data []byte, p gopacket.PacketBuilder) error {
	d := &DNS{}
	err := d.DecodeFromBytes(data, p)
	if err != nil {
		return err
	}
	p.AddLayer(d)
	p.SetApplicationLayer(d)
	return nil
}

func decodeIPSecAH(data []byte, p gopacket.PacketBuilder) error {
	i := &IPSecAH{
		ipv6ExtensionBase: decodeIPv6ExtensionBase(data),
		Reserved:          binary.BigEndian.Uint16(data[2:4]),
		SPI:               binary.BigEndian.Uint32(data[4:8]),
		Seq:               binary.BigEndian.Uint32(data[8:12]),
	}
	i.AuthenticationData = i.Contents[12:]
	p.AddLayer(i)
	return p.NextDecoder(i.NextHeader)
}

func decodeEthernetCTP(data []byte, p gopacket.PacketBuilder) error {
	c := &EthernetCTP{
		SkipCount: binary.LittleEndian.Uint16(data[:2]),
		BaseLayer: BaseLayer{data[:2], data[2:]},
	}
	if c.SkipCount%2 != 0 {
		return fmt.Errorf("EthernetCTP skip count is odd: %d", c.SkipCount)
	}
	p.AddLayer(c)
	return p.NextDecoder(gopacket.DecodeFunc(decodeEthernetCTPFromFunctionType))
}

func decodingLayerDecoder(d layerDecodingLayer, data []byte, p gopacket.PacketBuilder) error {
	err := d.DecodeFromBytes(data, p)
	if err != nil {
		return err
	}
	p.AddLayer(d)
	next := d.NextLayerType()
	if next == gopacket.LayerTypeZero {
		return nil
	}
	return p.NextDecoder(next)
}

func decodeSNAP(data []byte, p gopacket.PacketBuilder) error {
	s := &SNAP{
		OrganizationalCode: data[:3],
		Type:               EthernetType(binary.BigEndian.Uint16(data[3:5])),
		BaseLayer:          BaseLayer{data[:5], data[5:]},
	}
	p.AddLayer(s)
	// BUG(gconnell):  When decoding SNAP, we treat the SNAP type as an Ethernet
	// type.  This may not actually be an ethernet type in all cases,
	// depending on the organizational code.  Right now, we don't check.
	return p.NextDecoder(s.Type)
}

// decodePPPoE decodes the PPPoE header (see http://tools.ietf.org/html/rfc2516).
func decodePPPoE(data []byte, p gopacket.PacketBuilder) error {
	pppoe := &PPPoE{
		Version:   data[0] >> 4,
		Type:      data[0] & 0x0F,
		Code:      PPPoECode(data[1]),
		SessionId: binary.BigEndian.Uint16(data[2:4]),
		Length:    binary.BigEndian.Uint16(data[4:6]),
	}
	pppoe.BaseLayer = BaseLayer{data[:6], data[6 : 6+pppoe.Length]}
	p.AddLayer(pppoe)
	return p.NextDecoder(pppoe.Code)
}

func decodeSCTPHeartbeat(data []byte, p gopacket.PacketBuilder) error {
	sc := &SCTPHeartbeat{
		SCTPChunk: decodeSCTPChunk(data),
	}
	paramData := data[4:sc.Length]
	for len(paramData) > 0 {
		p := SCTPHeartbeatParameter(decodeSCTPParameter(paramData))
		paramData = paramData[p.ActualLength:]
		sc.Parameters = append(sc.Parameters, p)
	}
	p.AddLayer(sc)
	return p.NextDecoder(gopacket.DecodeFunc(decodeWithSCTPChunkTypePrefix))
}

func decodeIPv6Fragment(data []byte, p gopacket.PacketBuilder) error {
	i := &IPv6Fragment{
		BaseLayer:      BaseLayer{data[:8], data[8:]},
		NextHeader:     IPProtocol(data[0]),
		Reserved1:      data[1],
		FragmentOffset: binary.BigEndian.Uint16(data[2:4]) >> 3,
		Reserved2:      data[3] & 0x6 >> 1,
		MoreFragments:  data[3]&0x1 != 0,
		Identification: binary.BigEndian.Uint32(data[4:8]),
	}
	p.AddLayer(i)
	return p.NextDecoder(gopacket.DecodeFragment)
}

func decodeNortelDiscovery(data []byte, p gopacket.PacketBuilder) error {
	c := &NortelDiscovery{}
	if len(data) < 11 {
		return fmt.Errorf("Invalid NortelDiscovery packet length %d", len(data))
	}
	c.IPAddress = data[0:4]
	c.SegmentID = data[4:7]
	c.Chassis = NDPChassisType(data[7])
	c.Backplane = NDPBackplaneType(data[8])
	c.State = NDPState(data[9])
	c.NumLinks = uint8(data[10])
	p.AddLayer(c)
	return nil
}