TUN-6666: Define packet package

This package defines IP and ICMP packet, decoders, encoder and flow
2025-07-28 19:59:57 +00:00 · 2022-08-17 16:46:49 +01:00
parent 20ed7557f9
commit bad2e8e812
242 changed files with 49761 additions and 2642 deletions
--- a/vendor/github.com/google/gopacket/layers/icmp6msg.go
+++ b/vendor/github.com/google/gopacket/layers/icmp6msg.go
@@ -0,0 +1,578 @@
+// Copyright 2012 Google, Inc. All rights reserved.
+// Copyright 2009-2011 Andreas Krennmair. 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"
+	"encoding/hex"
+	"errors"
+	"fmt"
+	"net"
+	"time"
+
+	"github.com/google/gopacket"
+)
+
+// Based on RFC 4861
+
+// ICMPv6Opt indicate how to decode the data associated with each ICMPv6Option.
+type ICMPv6Opt uint8
+
+const (
+	_ ICMPv6Opt = iota
+
+	// ICMPv6OptSourceAddress contains the link-layer address of the sender of
+	// the packet. It is used in the Neighbor Solicitation, Router
+	// Solicitation, and Router Advertisement packets. Must be ignored for other
+	// Neighbor discovery messages.
+	ICMPv6OptSourceAddress
+
+	// ICMPv6OptTargetAddress contains the link-layer address of the target. It
+	// is used in Neighbor Advertisement and Redirect packets. Must be ignored
+	// for other Neighbor discovery messages.
+	ICMPv6OptTargetAddress
+
+	// ICMPv6OptPrefixInfo provides hosts with on-link prefixes and prefixes
+	// for Address Autoconfiguration. The Prefix Information option appears in
+	// Router Advertisement packets and MUST be silently ignored for other
+	// messages.
+	ICMPv6OptPrefixInfo
+
+	// ICMPv6OptRedirectedHeader is used in Redirect messages and contains all
+	// or part of the packet that is being redirected.
+	ICMPv6OptRedirectedHeader
+
+	// ICMPv6OptMTU is used in Router Advertisement messages to ensure that all
+	// nodes on a link use the same MTU value in those cases where the link MTU
+	// is not well known. This option MUST be silently ignored for other
+	// Neighbor Discovery messages.
+	ICMPv6OptMTU
+)
+
+// ICMPv6Echo represents the structure of a ping.
+type ICMPv6Echo struct {
+	BaseLayer
+	Identifier uint16
+	SeqNumber  uint16
+}
+
+// ICMPv6RouterSolicitation is sent by hosts to find routers.
+type ICMPv6RouterSolicitation struct {
+	BaseLayer
+	Options ICMPv6Options
+}
+
+// ICMPv6RouterAdvertisement is sent by routers in response to Solicitation.
+type ICMPv6RouterAdvertisement struct {
+	BaseLayer
+	HopLimit       uint8
+	Flags          uint8
+	RouterLifetime uint16
+	ReachableTime  uint32
+	RetransTimer   uint32
+	Options        ICMPv6Options
+}
+
+// ICMPv6NeighborSolicitation is sent to request the link-layer address of a
+// target node.
+type ICMPv6NeighborSolicitation struct {
+	BaseLayer
+	TargetAddress net.IP
+	Options       ICMPv6Options
+}
+
+// ICMPv6NeighborAdvertisement is sent by nodes in response to Solicitation.
+type ICMPv6NeighborAdvertisement struct {
+	BaseLayer
+	Flags         uint8
+	TargetAddress net.IP
+	Options       ICMPv6Options
+}
+
+// ICMPv6Redirect is sent by routers to inform hosts of a better first-hop node
+// on the path to a destination.
+type ICMPv6Redirect struct {
+	BaseLayer
+	TargetAddress      net.IP
+	DestinationAddress net.IP
+	Options            ICMPv6Options
+}
+
+// ICMPv6Option contains the type and data for a single option.
+type ICMPv6Option struct {
+	Type ICMPv6Opt
+	Data []byte
+}
+
+// ICMPv6Options is a slice of ICMPv6Option.
+type ICMPv6Options []ICMPv6Option
+
+func (i ICMPv6Opt) String() string {
+	switch i {
+	case ICMPv6OptSourceAddress:
+		return "SourceAddress"
+	case ICMPv6OptTargetAddress:
+		return "TargetAddress"
+	case ICMPv6OptPrefixInfo:
+		return "PrefixInfo"
+	case ICMPv6OptRedirectedHeader:
+		return "RedirectedHeader"
+	case ICMPv6OptMTU:
+		return "MTU"
+	default:
+		return fmt.Sprintf("Unknown(%d)", i)
+	}
+}
+
+// CanDecode returns the set of layer types that this DecodingLayer can decode.
+func (i *ICMPv6Echo) CanDecode() gopacket.LayerClass {
+	return LayerTypeICMPv6Echo
+}
+
+// LayerType returns LayerTypeICMPv6Echo.
+func (i *ICMPv6Echo) LayerType() gopacket.LayerType {
+	return LayerTypeICMPv6Echo
+}
+
+// NextLayerType returns the layer type contained by this DecodingLayer.
+func (i *ICMPv6Echo) NextLayerType() gopacket.LayerType {
+	return gopacket.LayerTypePayload
+}
+
+// DecodeFromBytes decodes the given bytes into this layer.
+func (i *ICMPv6Echo) DecodeFromBytes(data []byte, df gopacket.DecodeFeedback) error {
+	if len(data) < 4 {
+		df.SetTruncated()
+		return errors.New("ICMP layer less then 4 bytes for ICMPv6 Echo")
+	}
+	i.Identifier = binary.BigEndian.Uint16(data[0:2])
+	i.SeqNumber = binary.BigEndian.Uint16(data[2:4])
+
+	return nil
+}
+
+// SerializeTo writes the serialized form of this layer into the
+// SerializationBuffer, implementing gopacket.SerializableLayer.
+// See the docs for gopacket.SerializableLayer for more info.
+func (i *ICMPv6Echo) SerializeTo(b gopacket.SerializeBuffer, opts gopacket.SerializeOptions) error {
+	buf, err := b.PrependBytes(4)
+	if err != nil {
+		return err
+	}
+
+	binary.BigEndian.PutUint16(buf, i.Identifier)
+	binary.BigEndian.PutUint16(buf[2:], i.SeqNumber)
+	return nil
+}
+
+// LayerType returns LayerTypeICMPv6.
+func (i *ICMPv6RouterSolicitation) LayerType() gopacket.LayerType {
+	return LayerTypeICMPv6RouterSolicitation
+}
+
+// NextLayerType returns the layer type contained by this DecodingLayer.
+func (i *ICMPv6RouterSolicitation) NextLayerType() gopacket.LayerType {
+	return gopacket.LayerTypePayload
+}
+
+// DecodeFromBytes decodes the given bytes into this layer.
+func (i *ICMPv6RouterSolicitation) DecodeFromBytes(data []byte, df gopacket.DecodeFeedback) error {
+	// first 4 bytes are reserved followed by options
+	if len(data) < 4 {
+		df.SetTruncated()
+		return errors.New("ICMP layer less then 4 bytes for ICMPv6 router solicitation")
+	}
+
+	// truncate old options
+	i.Options = i.Options[:0]
+
+	return i.Options.DecodeFromBytes(data[4:], df)
+}
+
+// SerializeTo writes the serialized form of this layer into the
+// SerializationBuffer, implementing gopacket.SerializableLayer.
+// See the docs for gopacket.SerializableLayer for more info.
+func (i *ICMPv6RouterSolicitation) SerializeTo(b gopacket.SerializeBuffer, opts gopacket.SerializeOptions) error {
+	if err := i.Options.SerializeTo(b, opts); err != nil {
+		return err
+	}
+
+	buf, err := b.PrependBytes(4)
+	if err != nil {
+		return err
+	}
+
+	copy(buf, lotsOfZeros[:4])
+	return nil
+}
+
+// CanDecode returns the set of layer types that this DecodingLayer can decode.
+func (i *ICMPv6RouterSolicitation) CanDecode() gopacket.LayerClass {
+	return LayerTypeICMPv6RouterSolicitation
+}
+
+// LayerType returns LayerTypeICMPv6RouterAdvertisement.
+func (i *ICMPv6RouterAdvertisement) LayerType() gopacket.LayerType {
+	return LayerTypeICMPv6RouterAdvertisement
+}
+
+// NextLayerType returns the layer type contained by this DecodingLayer.
+func (i *ICMPv6RouterAdvertisement) NextLayerType() gopacket.LayerType {
+	return gopacket.LayerTypePayload
+}
+
+// DecodeFromBytes decodes the given bytes into this layer.
+func (i *ICMPv6RouterAdvertisement) DecodeFromBytes(data []byte, df gopacket.DecodeFeedback) error {
+	if len(data) < 12 {
+		df.SetTruncated()
+		return errors.New("ICMP layer less then 12 bytes for ICMPv6 router advertisement")
+	}
+
+	i.HopLimit = uint8(data[0])
+	// M, O bit followed by 6 reserved bits
+	i.Flags = uint8(data[1])
+	i.RouterLifetime = binary.BigEndian.Uint16(data[2:4])
+	i.ReachableTime = binary.BigEndian.Uint32(data[4:8])
+	i.RetransTimer = binary.BigEndian.Uint32(data[8:12])
+	i.BaseLayer = BaseLayer{data, nil} // assume no payload
+
+	// truncate old options
+	i.Options = i.Options[:0]
+
+	return i.Options.DecodeFromBytes(data[12:], df)
+}
+
+// SerializeTo writes the serialized form of this layer into the
+// SerializationBuffer, implementing gopacket.SerializableLayer.
+// See the docs for gopacket.SerializableLayer for more info.
+func (i *ICMPv6RouterAdvertisement) SerializeTo(b gopacket.SerializeBuffer, opts gopacket.SerializeOptions) error {
+	if err := i.Options.SerializeTo(b, opts); err != nil {
+		return err
+	}
+
+	buf, err := b.PrependBytes(12)
+	if err != nil {
+		return err
+	}
+
+	buf[0] = byte(i.HopLimit)
+	buf[1] = byte(i.Flags)
+	binary.BigEndian.PutUint16(buf[2:], i.RouterLifetime)
+	binary.BigEndian.PutUint32(buf[4:], i.ReachableTime)
+	binary.BigEndian.PutUint32(buf[8:], i.RetransTimer)
+	return nil
+}
+
+// CanDecode returns the set of layer types that this DecodingLayer can decode.
+func (i *ICMPv6RouterAdvertisement) CanDecode() gopacket.LayerClass {
+	return LayerTypeICMPv6RouterAdvertisement
+}
+
+// ManagedAddressConfig is true when addresses are available via DHCPv6. If
+// set, the OtherConfig flag is redundant.
+func (i *ICMPv6RouterAdvertisement) ManagedAddressConfig() bool {
+	return i.Flags&0x80 != 0
+}
+
+// OtherConfig is true when there is other configuration information available
+// via DHCPv6. For example, DNS-related information.
+func (i *ICMPv6RouterAdvertisement) OtherConfig() bool {
+	return i.Flags&0x40 != 0
+}
+
+// LayerType returns LayerTypeICMPv6NeighborSolicitation.
+func (i *ICMPv6NeighborSolicitation) LayerType() gopacket.LayerType {
+	return LayerTypeICMPv6NeighborSolicitation
+}
+
+// NextLayerType returns the layer type contained by this DecodingLayer.
+func (i *ICMPv6NeighborSolicitation) NextLayerType() gopacket.LayerType {
+	return gopacket.LayerTypePayload
+}
+
+// DecodeFromBytes decodes the given bytes into this layer.
+func (i *ICMPv6NeighborSolicitation) DecodeFromBytes(data []byte, df gopacket.DecodeFeedback) error {
+	if len(data) < 20 {
+		df.SetTruncated()
+		return errors.New("ICMP layer less then 20 bytes for ICMPv6 neighbor solicitation")
+	}
+
+	i.TargetAddress = net.IP(data[4:20])
+	i.BaseLayer = BaseLayer{data, nil} // assume no payload
+
+	// truncate old options
+	i.Options = i.Options[:0]
+
+	return i.Options.DecodeFromBytes(data[20:], df)
+}
+
+// SerializeTo writes the serialized form of this layer into the
+// SerializationBuffer, implementing gopacket.SerializableLayer.
+// See the docs for gopacket.SerializableLayer for more info.
+func (i *ICMPv6NeighborSolicitation) SerializeTo(b gopacket.SerializeBuffer, opts gopacket.SerializeOptions) error {
+	if err := i.Options.SerializeTo(b, opts); err != nil {
+		return err
+	}
+
+	buf, err := b.PrependBytes(20)
+	if err != nil {
+		return err
+	}
+
+	copy(buf, lotsOfZeros[:4])
+	copy(buf[4:], i.TargetAddress)
+	return nil
+}
+
+// CanDecode returns the set of layer types that this DecodingLayer can decode.
+func (i *ICMPv6NeighborSolicitation) CanDecode() gopacket.LayerClass {
+	return LayerTypeICMPv6NeighborSolicitation
+}
+
+// LayerType returns LayerTypeICMPv6NeighborAdvertisement.
+func (i *ICMPv6NeighborAdvertisement) LayerType() gopacket.LayerType {
+	return LayerTypeICMPv6NeighborAdvertisement
+}
+
+// NextLayerType returns the layer type contained by this DecodingLayer.
+func (i *ICMPv6NeighborAdvertisement) NextLayerType() gopacket.LayerType {
+	return gopacket.LayerTypePayload
+}
+
+// DecodeFromBytes decodes the given bytes into this layer.
+func (i *ICMPv6NeighborAdvertisement) DecodeFromBytes(data []byte, df gopacket.DecodeFeedback) error {
+	if len(data) < 20 {
+		df.SetTruncated()
+		return errors.New("ICMP layer less then 20 bytes for ICMPv6 neighbor advertisement")
+	}
+
+	i.Flags = uint8(data[0])
+	i.TargetAddress = net.IP(data[4:20])
+	i.BaseLayer = BaseLayer{data, nil} // assume no payload
+
+	// truncate old options
+	i.Options = i.Options[:0]
+
+	return i.Options.DecodeFromBytes(data[20:], df)
+}
+
+// SerializeTo writes the serialized form of this layer into the
+// SerializationBuffer, implementing gopacket.SerializableLayer.
+// See the docs for gopacket.SerializableLayer for more info.
+func (i *ICMPv6NeighborAdvertisement) SerializeTo(b gopacket.SerializeBuffer, opts gopacket.SerializeOptions) error {
+	if err := i.Options.SerializeTo(b, opts); err != nil {
+		return err
+	}
+
+	buf, err := b.PrependBytes(20)
+	if err != nil {
+		return err
+	}
+
+	buf[0] = byte(i.Flags)
+	copy(buf[1:], lotsOfZeros[:3])
+	copy(buf[4:], i.TargetAddress)
+	return nil
+}
+
+// CanDecode returns the set of layer types that this DecodingLayer can decode.
+func (i *ICMPv6NeighborAdvertisement) CanDecode() gopacket.LayerClass {
+	return LayerTypeICMPv6NeighborAdvertisement
+}
+
+// Router indicates whether the sender is a router or not.
+func (i *ICMPv6NeighborAdvertisement) Router() bool {
+	return i.Flags&0x80 != 0
+}
+
+// Solicited indicates whether the advertisement was solicited or not.
+func (i *ICMPv6NeighborAdvertisement) Solicited() bool {
+	return i.Flags&0x40 != 0
+}
+
+// Override indicates whether the advertisement should Override an existing
+// cache entry.
+func (i *ICMPv6NeighborAdvertisement) Override() bool {
+	return i.Flags&0x20 != 0
+}
+
+// LayerType returns LayerTypeICMPv6Redirect.
+func (i *ICMPv6Redirect) LayerType() gopacket.LayerType {
+	return LayerTypeICMPv6Redirect
+}
+
+// NextLayerType returns the layer type contained by this DecodingLayer.
+func (i *ICMPv6Redirect) NextLayerType() gopacket.LayerType {
+	return gopacket.LayerTypePayload
+}
+
+// DecodeFromBytes decodes the given bytes into this layer.
+func (i *ICMPv6Redirect) DecodeFromBytes(data []byte, df gopacket.DecodeFeedback) error {
+	if len(data) < 36 {
+		df.SetTruncated()
+		return errors.New("ICMP layer less then 36 bytes for ICMPv6 redirect")
+	}
+
+	i.TargetAddress = net.IP(data[4:20])
+	i.DestinationAddress = net.IP(data[20:36])
+	i.BaseLayer = BaseLayer{data, nil} // assume no payload
+
+	// truncate old options
+	i.Options = i.Options[:0]
+
+	return i.Options.DecodeFromBytes(data[36:], df)
+}
+
+// SerializeTo writes the serialized form of this layer into the
+// SerializationBuffer, implementing gopacket.SerializableLayer.
+// See the docs for gopacket.SerializableLayer for more info.
+func (i *ICMPv6Redirect) SerializeTo(b gopacket.SerializeBuffer, opts gopacket.SerializeOptions) error {
+	if err := i.Options.SerializeTo(b, opts); err != nil {
+		return err
+	}
+
+	buf, err := b.PrependBytes(36)
+	if err != nil {
+		return err
+	}
+
+	copy(buf, lotsOfZeros[:4])
+	copy(buf[4:], i.TargetAddress)
+	copy(buf[20:], i.DestinationAddress)
+	return nil
+}
+
+// CanDecode returns the set of layer types that this DecodingLayer can decode.
+func (i *ICMPv6Redirect) CanDecode() gopacket.LayerClass {
+	return LayerTypeICMPv6Redirect
+}
+
+func (i ICMPv6Option) String() string {
+	hd := hex.EncodeToString(i.Data)
+	if len(hd) > 0 {
+		hd = " 0x" + hd
+	}
+
+	switch i.Type {
+	case ICMPv6OptSourceAddress, ICMPv6OptTargetAddress:
+		return fmt.Sprintf("ICMPv6Option(%s:%v)",
+			i.Type,
+			net.HardwareAddr(i.Data))
+	case ICMPv6OptPrefixInfo:
+		if len(i.Data) == 30 {
+			prefixLen := uint8(i.Data[0])
+			onLink := (i.Data[1]&0x80 != 0)
+			autonomous := (i.Data[1]&0x40 != 0)
+			validLifetime := time.Duration(binary.BigEndian.Uint32(i.Data[2:6])) * time.Second
+			preferredLifetime := time.Duration(binary.BigEndian.Uint32(i.Data[6:10])) * time.Second
+
+			prefix := net.IP(i.Data[14:])
+
+			return fmt.Sprintf("ICMPv6Option(%s:%v/%v:%t:%t:%v:%v)",
+				i.Type,
+				prefix, prefixLen,
+				onLink, autonomous,
+				validLifetime, preferredLifetime)
+		}
+	case ICMPv6OptRedirectedHeader:
+		// could invoke IP decoder on data... probably best not to
+		break
+	case ICMPv6OptMTU:
+		if len(i.Data) == 6 {
+			return fmt.Sprintf("ICMPv6Option(%s:%v)",
+				i.Type,
+				binary.BigEndian.Uint32(i.Data[2:]))
+		}
+
+	}
+	return fmt.Sprintf("ICMPv6Option(%s:%s)", i.Type, hd)
+}
+
+// DecodeFromBytes decodes the given bytes into this layer.
+func (i *ICMPv6Options) DecodeFromBytes(data []byte, df gopacket.DecodeFeedback) error {
+	for len(data) > 0 {
+		if len(data) < 2 {
+			df.SetTruncated()
+			return errors.New("ICMP layer less then 2 bytes for ICMPv6 message option")
+		}
+
+		// unit is 8 octets, convert to bytes
+		length := int(data[1]) * 8
+
+		if length == 0 {
+			df.SetTruncated()
+			return errors.New("ICMPv6 message option with length 0")
+		}
+
+		if len(data) < length {
+			df.SetTruncated()
+			return fmt.Errorf("ICMP layer only %v bytes for ICMPv6 message option with length %v", len(data), length)
+		}
+
+		o := ICMPv6Option{
+			Type: ICMPv6Opt(data[0]),
+			Data: data[2:length],
+		}
+
+		// chop off option we just consumed
+		data = data[length:]
+
+		*i = append(*i, o)
+	}
+
+	return nil
+}
+
+// SerializeTo writes the serialized form of this layer into the
+// SerializationBuffer, implementing gopacket.SerializableLayer.
+// See the docs for gopacket.SerializableLayer for more info.
+func (i *ICMPv6Options) SerializeTo(b gopacket.SerializeBuffer, opts gopacket.SerializeOptions) error {
+	for _, opt := range []ICMPv6Option(*i) {
+		length := len(opt.Data) + 2
+		buf, err := b.PrependBytes(length)
+		if err != nil {
+			return err
+		}
+
+		buf[0] = byte(opt.Type)
+		buf[1] = byte(length / 8)
+		copy(buf[2:], opt.Data)
+	}
+
+	return nil
+}
+
+func decodeICMPv6Echo(data []byte, p gopacket.PacketBuilder) error {
+	i := &ICMPv6Echo{}
+	return decodingLayerDecoder(i, data, p)
+}
+
+func decodeICMPv6RouterSolicitation(data []byte, p gopacket.PacketBuilder) error {
+	i := &ICMPv6RouterSolicitation{}
+	return decodingLayerDecoder(i, data, p)
+}
+
+func decodeICMPv6RouterAdvertisement(data []byte, p gopacket.PacketBuilder) error {
+	i := &ICMPv6RouterAdvertisement{}
+	return decodingLayerDecoder(i, data, p)
+}
+
+func decodeICMPv6NeighborSolicitation(data []byte, p gopacket.PacketBuilder) error {
+	i := &ICMPv6NeighborSolicitation{}
+	return decodingLayerDecoder(i, data, p)
+}
+
+func decodeICMPv6NeighborAdvertisement(data []byte, p gopacket.PacketBuilder) error {
+	i := &ICMPv6NeighborAdvertisement{}
+	return decodingLayerDecoder(i, data, p)
+}
+
+func decodeICMPv6Redirect(data []byte, p gopacket.PacketBuilder) error {
+	i := &ICMPv6Redirect{}
+	return decodingLayerDecoder(i, data, p)
+}