diff options
Diffstat (limited to 'vendor/github.com/google/gopacket/layers/bfd.go')
| -rw-r--r-- | vendor/github.com/google/gopacket/layers/bfd.go | 481 |
1 files changed, 0 insertions, 481 deletions
diff --git a/vendor/github.com/google/gopacket/layers/bfd.go b/vendor/github.com/google/gopacket/layers/bfd.go deleted file mode 100644 index 43030fb..0000000 --- a/vendor/github.com/google/gopacket/layers/bfd.go +++ /dev/null @@ -1,481 +0,0 @@ -// Copyright 2017 Google, Inc. 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" - "errors" - - "github.com/google/gopacket" -) - -// BFD Control Packet Format -// ------------------------- -// The current version of BFD's RFC (RFC 5880) contains the following -// diagram for the BFD Control packet format: -// -// 0 1 2 3 -// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 -// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ -// |Vers | Diag |Sta|P|F|C|A|D|M| Detect Mult | Length | -// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ -// | My Discriminator | -// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ -// | Your Discriminator | -// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ -// | Desired Min TX Interval | -// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ -// | Required Min RX Interval | -// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ -// | Required Min Echo RX Interval | -// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ -// -// An optional Authentication Section MAY be present: -// -// 0 1 2 3 -// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 -// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ -// | Auth Type | Auth Len | Authentication Data... | -// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ -// -// -// Simple Password Authentication Section Format -// --------------------------------------------- -// 0 1 2 3 -// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 -// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ -// | Auth Type | Auth Len | Auth Key ID | Password... | -// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ -// | ... | -// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ -// -// -// Keyed MD5 and Meticulous Keyed MD5 Authentication Section Format -// ---------------------------------------------------------------- -// 0 1 2 3 -// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 -// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ -// | Auth Type | Auth Len | Auth Key ID | Reserved | -// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ -// | Sequence Number | -// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ -// | Auth Key/Digest... | -// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ -// | ... | -// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ -// -// -// Keyed SHA1 and Meticulous Keyed SHA1 Authentication Section Format -// ------------------------------------------------------------------ -// 0 1 2 3 -// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 -// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ -// | Auth Type | Auth Len | Auth Key ID | Reserved | -// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ -// | Sequence Number | -// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ -// | Auth Key/Hash... | -// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ -// | ... | -// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ -// -// From https://tools.ietf.org/rfc/rfc5880.txt -const bfdMinimumRecordSizeInBytes int = 24 - -// BFDVersion represents the version as decoded from the BFD control message -type BFDVersion uint8 - -// BFDDiagnostic represents diagnostic infomation about a BFD session -type BFDDiagnostic uint8 - -// constants that define BFDDiagnostic flags -const ( - BFDDiagnosticNone BFDDiagnostic = 0 // No Diagnostic - BFDDiagnosticTimeExpired BFDDiagnostic = 1 // Control Detection Time Expired - BFDDiagnosticEchoFailed BFDDiagnostic = 2 // Echo Function Failed - BFDDiagnosticNeighborSignalDown BFDDiagnostic = 3 // Neighbor Signaled Session Down - BFDDiagnosticForwardPlaneReset BFDDiagnostic = 4 // Forwarding Plane Reset - BFDDiagnosticPathDown BFDDiagnostic = 5 // Path Down - BFDDiagnosticConcatPathDown BFDDiagnostic = 6 // Concatenated Path Down - BFDDiagnosticAdminDown BFDDiagnostic = 7 // Administratively Down - BFDDiagnosticRevConcatPathDown BFDDiagnostic = 8 // Reverse Concatenated Path Dow -) - -// String returns a string version of BFDDiagnostic -func (bd BFDDiagnostic) String() string { - switch bd { - default: - return "Unknown" - case BFDDiagnosticNone: - return "None" - case BFDDiagnosticTimeExpired: - return "Control Detection Time Expired" - case BFDDiagnosticEchoFailed: - return "Echo Function Failed" - case BFDDiagnosticNeighborSignalDown: - return "Neighbor Signaled Session Down" - case BFDDiagnosticForwardPlaneReset: - return "Forwarding Plane Reset" - case BFDDiagnosticPathDown: - return "Path Down" - case BFDDiagnosticConcatPathDown: - return "Concatenated Path Down" - case BFDDiagnosticAdminDown: - return "Administratively Down" - case BFDDiagnosticRevConcatPathDown: - return "Reverse Concatenated Path Down" - } -} - -// BFDState represents the state of a BFD session -type BFDState uint8 - -// constants that define BFDState -const ( - BFDStateAdminDown BFDState = 0 - BFDStateDown BFDState = 1 - BFDStateInit BFDState = 2 - BFDStateUp BFDState = 3 -) - -// String returns a string version of BFDState -func (s BFDState) String() string { - switch s { - default: - return "Unknown" - case BFDStateAdminDown: - return "Admin Down" - case BFDStateDown: - return "Down" - case BFDStateInit: - return "Init" - case BFDStateUp: - return "Up" - } -} - -// BFDDetectMultiplier represents the negotiated transmit interval, -// multiplied by this value, provides the Detection Time for the -// receiving system in Asynchronous mode. -type BFDDetectMultiplier uint8 - -// BFDDiscriminator is a unique, nonzero discriminator value used -// to demultiplex multiple BFD sessions between the same pair of systems. -type BFDDiscriminator uint32 - -// BFDTimeInterval represents a time interval in microseconds -type BFDTimeInterval uint32 - -// BFDAuthType represents the authentication used in the BFD session -type BFDAuthType uint8 - -// constants that define the BFDAuthType -const ( - BFDAuthTypeNone BFDAuthType = 0 // No Auth - BFDAuthTypePassword BFDAuthType = 1 // Simple Password - BFDAuthTypeKeyedMD5 BFDAuthType = 2 // Keyed MD5 - BFDAuthTypeMeticulousKeyedMD5 BFDAuthType = 3 // Meticulous Keyed MD5 - BFDAuthTypeKeyedSHA1 BFDAuthType = 4 // Keyed SHA1 - BFDAuthTypeMeticulousKeyedSHA1 BFDAuthType = 5 // Meticulous Keyed SHA1 -) - -// String returns a string version of BFDAuthType -func (at BFDAuthType) String() string { - switch at { - default: - return "Unknown" - case BFDAuthTypeNone: - return "No Authentication" - case BFDAuthTypePassword: - return "Simple Password" - case BFDAuthTypeKeyedMD5: - return "Keyed MD5" - case BFDAuthTypeMeticulousKeyedMD5: - return "Meticulous Keyed MD5" - case BFDAuthTypeKeyedSHA1: - return "Keyed SHA1" - case BFDAuthTypeMeticulousKeyedSHA1: - return "Meticulous Keyed SHA1" - } -} - -// BFDAuthKeyID represents the authentication key ID in use for -// this packet. This allows multiple keys to be active simultaneously. -type BFDAuthKeyID uint8 - -// BFDAuthSequenceNumber represents the sequence number for this packet. -// For Keyed Authentication, this value is incremented occasionally. For -// Meticulous Keyed Authentication, this value is incremented for each -// successive packet transmitted for a session. This provides protection -// against replay attacks. -type BFDAuthSequenceNumber uint32 - -// BFDAuthData represents the authentication key or digest -type BFDAuthData []byte - -// BFDAuthHeader represents authentication data used in the BFD session -type BFDAuthHeader struct { - AuthType BFDAuthType - KeyID BFDAuthKeyID - SequenceNumber BFDAuthSequenceNumber - Data BFDAuthData -} - -// Length returns the data length of the BFDAuthHeader based on the -// authentication type -func (h *BFDAuthHeader) Length() int { - switch h.AuthType { - case BFDAuthTypePassword: - return 3 + len(h.Data) - case BFDAuthTypeKeyedMD5, BFDAuthTypeMeticulousKeyedMD5: - return 8 + len(h.Data) - case BFDAuthTypeKeyedSHA1, BFDAuthTypeMeticulousKeyedSHA1: - return 8 + len(h.Data) - default: - return 0 - } -} - -// BFD represents a BFD control message packet whose payload contains -// the control information required to for a BFD session. -// -// References -// ---------- -// -// Wikipedia's BFD entry: -// https://en.wikipedia.org/wiki/Bidirectional_Forwarding_Detection -// This is the best place to get an overview of BFD. -// -// RFC 5880 "Bidirectional Forwarding Detection (BFD)" (2010) -// https://tools.ietf.org/html/rfc5880 -// This is the original BFD specification. -// -// RFC 5881 "Bidirectional Forwarding Detection (BFD) for IPv4 and IPv6 (Single Hop)" (2010) -// https://tools.ietf.org/html/rfc5881 -// Describes the use of the Bidirectional Forwarding Detection (BFD) -// protocol over IPv4 and IPv6 for single IP hops. -type BFD struct { - BaseLayer // Stores the packet bytes and payload bytes. - - Version BFDVersion // Version of the BFD protocol. - Diagnostic BFDDiagnostic // Diagnostic code for last state change - State BFDState // Current state - Poll bool // Requesting verification - Final bool // Responding to a received BFD Control packet that had the Poll (P) bit set. - ControlPlaneIndependent bool // BFD implementation does not share fate with its control plane - AuthPresent bool // Authentication Section is present and the session is to be authenticated - Demand bool // Demand mode is active - Multipoint bool // For future point-to-multipoint extensions. Must always be zero - DetectMultiplier BFDDetectMultiplier // Detection time multiplier - MyDiscriminator BFDDiscriminator // A unique, nonzero discriminator value - YourDiscriminator BFDDiscriminator // discriminator received from the remote system. - DesiredMinTxInterval BFDTimeInterval // Minimum interval, in microseconds, the local system would like to use when transmitting BFD Control packets - RequiredMinRxInterval BFDTimeInterval // Minimum interval, in microseconds, between received BFD Control packets that this system is capable of supporting - RequiredMinEchoRxInterval BFDTimeInterval // Minimum interval, in microseconds, between received BFD Echo packets that this system is capable of supporting - AuthHeader *BFDAuthHeader // Authentication data, variable length. -} - -// Length returns the data length of a BFD Control message which -// changes based on the presence and type of authentication -// contained in the message -func (d *BFD) Length() int { - if d.AuthPresent && (d.AuthHeader != nil) { - return bfdMinimumRecordSizeInBytes + d.AuthHeader.Length() - } - - return bfdMinimumRecordSizeInBytes -} - -// LayerType returns the layer type of the BFD object, which is LayerTypeBFD. -func (d *BFD) LayerType() gopacket.LayerType { - return LayerTypeBFD -} - -// decodeBFD analyses a byte slice and attempts to decode it as a BFD -// control packet -// -// If it succeeds, it loads p with information about the packet and returns nil. -// If it fails, it returns an error (non nil). -// -// This function is employed in layertypes.go to register the BFD layer. -func decodeBFD(data []byte, p gopacket.PacketBuilder) error { - - // Attempt to decode the byte slice. - d := &BFD{} - err := d.DecodeFromBytes(data, p) - if err != nil { - return err - } - - // If the decoding worked, add the layer to the packet and set it - // as the application layer too, if there isn't already one. - p.AddLayer(d) - p.SetApplicationLayer(d) - - return nil -} - -// DecodeFromBytes analyses a byte slice and attempts to decode it as a BFD -// control packet. -// -// Upon succeeds, it loads the BFD object with information about the packet -// and returns nil. -// Upon failure, it returns an error (non nil). -func (d *BFD) DecodeFromBytes(data []byte, df gopacket.DecodeFeedback) error { - - // If the data block is too short to be a BFD record, then return an error. - if len(data) < bfdMinimumRecordSizeInBytes { - df.SetTruncated() - return errors.New("BFD packet too short") - } - - pLen := uint8(data[3]) - if len(data) != int(pLen) { - return errors.New("BFD packet length does not match") - } - - // BFD type embeds type BaseLayer which contains two fields: - // Contents is supposed to contain the bytes of the data at this level. - // Payload is supposed to contain the payload of this level. - // Here we set the baselayer to be the bytes of the BFD record. - d.BaseLayer = BaseLayer{Contents: data[:len(data)]} - - // Extract the fields from the block of bytes. - // To make sense of this, refer to the packet diagram - // above and the section on endian conventions. - - // The first few fields are all packed into the first 32 bits. Unpack them. - d.Version = BFDVersion(((data[0] & 0xE0) >> 5)) - d.Diagnostic = BFDDiagnostic(data[0] & 0x1F) - data = data[1:] - - d.State = BFDState((data[0] & 0xC0) >> 6) - d.Poll = data[0]&0x20 != 0 - d.Final = data[0]&0x10 != 0 - d.ControlPlaneIndependent = data[0]&0x08 != 0 - d.AuthPresent = data[0]&0x04 != 0 - d.Demand = data[0]&0x02 != 0 - d.Multipoint = data[0]&0x01 != 0 - data = data[1:] - - data, d.DetectMultiplier = data[1:], BFDDetectMultiplier(data[0]) - data, _ = data[1:], uint8(data[0]) // Consume length - - // The remaining fields can just be copied in big endian order. - data, d.MyDiscriminator = data[4:], BFDDiscriminator(binary.BigEndian.Uint32(data[:4])) - data, d.YourDiscriminator = data[4:], BFDDiscriminator(binary.BigEndian.Uint32(data[:4])) - data, d.DesiredMinTxInterval = data[4:], BFDTimeInterval(binary.BigEndian.Uint32(data[:4])) - data, d.RequiredMinRxInterval = data[4:], BFDTimeInterval(binary.BigEndian.Uint32(data[:4])) - data, d.RequiredMinEchoRxInterval = data[4:], BFDTimeInterval(binary.BigEndian.Uint32(data[:4])) - - if d.AuthPresent && (len(data) > 2) { - d.AuthHeader = &BFDAuthHeader{} - data, d.AuthHeader.AuthType = data[1:], BFDAuthType(data[0]) - data, _ = data[1:], uint8(data[0]) // Consume length - data, d.AuthHeader.KeyID = data[1:], BFDAuthKeyID(data[0]) - - switch d.AuthHeader.AuthType { - case BFDAuthTypePassword: - d.AuthHeader.Data = BFDAuthData(data) - case BFDAuthTypeKeyedMD5, BFDAuthTypeMeticulousKeyedMD5: - // Skipped reserved byte - data, d.AuthHeader.SequenceNumber = data[5:], BFDAuthSequenceNumber(binary.BigEndian.Uint32(data[1:5])) - d.AuthHeader.Data = BFDAuthData(data) - case BFDAuthTypeKeyedSHA1, BFDAuthTypeMeticulousKeyedSHA1: - // Skipped reserved byte - data, d.AuthHeader.SequenceNumber = data[5:], BFDAuthSequenceNumber(binary.BigEndian.Uint32(data[1:5])) - d.AuthHeader.Data = BFDAuthData(data) - } - } - - 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 (d *BFD) SerializeTo(b gopacket.SerializeBuffer, opts gopacket.SerializeOptions) error { - data, err := b.PrependBytes(bfdMinimumRecordSizeInBytes) - if err != nil { - return err - } - - // Pack the first few fields into the first 32 bits. - data[0] = byte(byte(d.Version<<5) | byte(d.Diagnostic)) - h := uint8(0) - h |= (uint8(d.State) << 6) - h |= (uint8(bool2uint8(d.Poll)) << 5) - h |= (uint8(bool2uint8(d.Final)) << 4) - h |= (uint8(bool2uint8(d.ControlPlaneIndependent)) << 3) - h |= (uint8(bool2uint8(d.AuthPresent)) << 2) - h |= (uint8(bool2uint8(d.Demand)) << 1) - h |= uint8(bool2uint8(d.Multipoint)) - data[1] = byte(h) - data[2] = byte(d.DetectMultiplier) - data[3] = byte(d.Length()) - - // The remaining fields can just be copied in big endian order. - binary.BigEndian.PutUint32(data[4:], uint32(d.MyDiscriminator)) - binary.BigEndian.PutUint32(data[8:], uint32(d.YourDiscriminator)) - binary.BigEndian.PutUint32(data[12:], uint32(d.DesiredMinTxInterval)) - binary.BigEndian.PutUint32(data[16:], uint32(d.RequiredMinRxInterval)) - binary.BigEndian.PutUint32(data[20:], uint32(d.RequiredMinEchoRxInterval)) - - if d.AuthPresent && (d.AuthHeader != nil) { - auth, err := b.AppendBytes(int(d.AuthHeader.Length())) - if err != nil { - return err - } - - auth[0] = byte(d.AuthHeader.AuthType) - auth[1] = byte(d.AuthHeader.Length()) - auth[2] = byte(d.AuthHeader.KeyID) - - switch d.AuthHeader.AuthType { - case BFDAuthTypePassword: - copy(auth[3:], d.AuthHeader.Data) - case BFDAuthTypeKeyedMD5, BFDAuthTypeMeticulousKeyedMD5: - auth[3] = byte(0) - binary.BigEndian.PutUint32(auth[4:], uint32(d.AuthHeader.SequenceNumber)) - copy(auth[8:], d.AuthHeader.Data) - case BFDAuthTypeKeyedSHA1, BFDAuthTypeMeticulousKeyedSHA1: - auth[3] = byte(0) - binary.BigEndian.PutUint32(auth[4:], uint32(d.AuthHeader.SequenceNumber)) - copy(auth[8:], d.AuthHeader.Data) - } - } - - return nil -} - -// CanDecode returns a set of layers that BFD objects can decode. -// As BFD objects can only decide the BFD layer, we can return just that layer. -// Apparently a single layer type implements LayerClass. -func (d *BFD) CanDecode() gopacket.LayerClass { - return LayerTypeBFD -} - -// NextLayerType specifies the next layer that GoPacket should attempt to -// analyse after this (BFD) layer. As BFD packets do not contain any payload -// bytes, there are no further layers to analyse. -func (d *BFD) NextLayerType() gopacket.LayerType { - return gopacket.LayerTypeZero -} - -// Payload returns an empty byte slice as BFD packets do not carry a payload -func (d *BFD) Payload() []byte { - return nil -} - -// bool2uint8 converts a bool to uint8 -func bool2uint8(b bool) uint8 { - if b { - return 1 - } - return 0 -} |