Method Decode

packet/decoder.go:142–184

(packet RawPacket)

}

func (pd *ICMPDecoder) Decode(packet RawPacket) (*ICMP, error) {
	// Should decode to IP and optionally ICMP layer
	decoded, err := pd.decodeByVersion(packet.Data)
	if err != nil {
		return nil, err
	}

	for _, layerType := range decoded {
		switch layerType {
		case layers.LayerTypeICMPv4:
			ipv4, err := newIPv4(pd.ipv4)
			if err != nil {
				return nil, err
			}
			msg, err := icmp.ParseMessage(int(layers.IPProtocolICMPv4), append(pd.icmpv4.Contents, pd.icmpv4.Payload...))
			if err != nil {
				return nil, errors.Wrap(err, "failed to parse ICMPv4 message")
			}
			return &ICMP{
				IP:      ipv4,
				Message: msg,
			}, nil
		case layers.LayerTypeICMPv6:
			ipv6, err := newIPv6(pd.ipv6)
			if err != nil {
				return nil, err
			}
			msg, err := icmp.ParseMessage(int(layers.IPProtocolICMPv6), append(pd.icmpv6.Contents, pd.icmpv6.Payload...))
			if err != nil {
				return nil, errors.Wrap(err, "failed to parse ICMPv6")
			}
			return &ICMP{
				IP:      ipv6,
				Message: msg,
			}, nil
		}
	}
	layers := make([]string, len(decoded))
	for i, l := range decoded {
		layers[i] = l.String()
	}
	return nil, fmt.Errorf("Expect to decode IP and ICMP layers, got %s", layers)
}