From 3f1edad4e6ba0a7876750aea55507fae14d8badf Mon Sep 17 00:00:00 2001 From: Milan Lenco Date: Wed, 11 Oct 2017 16:40:58 +0200 Subject: ODPM 266: Go-libmemif + 2 examples. Change-Id: Icdb9b9eb2314eff6c96afe7996fcf2728291de4a Signed-off-by: Milan Lenco --- vendor/github.com/google/gopacket/layers/vxlan.go | 94 +++++++++++++++++++++++ 1 file changed, 94 insertions(+) create mode 100644 vendor/github.com/google/gopacket/layers/vxlan.go (limited to 'vendor/github.com/google/gopacket/layers/vxlan.go') diff --git a/vendor/github.com/google/gopacket/layers/vxlan.go b/vendor/github.com/google/gopacket/layers/vxlan.go new file mode 100644 index 0000000..08f1ecb --- /dev/null +++ b/vendor/github.com/google/gopacket/layers/vxlan.go @@ -0,0 +1,94 @@ +// Copyright 2016 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" + "fmt" + "github.com/google/gopacket" +) + +// VXLAN is specifed in RFC 7348 https://tools.ietf.org/html/rfc7348 +// G, D, A, Group Policy ID from https://tools.ietf.org/html/draft-smith-vxlan-group-policy-00 +// 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 +// 0 8 16 24 32 +// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +// |G|R|R|R|I|R|R|R|R|D|R|R|A|R|R|R| Group Policy ID | +// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +// | 24 bit VXLAN Network Identifier | Reserved | +// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + +// VXLAN is a VXLAN packet header +type VXLAN struct { + BaseLayer + ValidIDFlag bool // 'I' bit per RFC 7348 + VNI uint32 // 'VXLAN Network Identifier' 24 bits per RFC 7348 + GBPExtension bool // 'G' bit per Group Policy https://tools.ietf.org/html/draft-smith-vxlan-group-policy-00 + GBPDontLearn bool // 'D' bit per Group Policy + GBPApplied bool // 'A' bit per Group Policy + GBPGroupPolicyID uint16 // 'Group Policy ID' 16 bits per Group Policy +} + +// LayerType returns LayerTypeVXLAN +func (vx *VXLAN) LayerType() gopacket.LayerType { return LayerTypeVXLAN } + +func decodeVXLAN(data []byte, p gopacket.PacketBuilder) error { + vx := &VXLAN{} + + // VNI is a 24bit number, Uint32 requires 32 bits + var buf [4]byte + copy(buf[1:], data[4:7]) + + // RFC 7348 https://tools.ietf.org/html/rfc7348 + vx.ValidIDFlag = data[0]&0x08 > 0 // 'I' bit per RFC7348 + vx.VNI = binary.BigEndian.Uint32(buf[:]) // VXLAN Network Identifier per RFC7348 + + // Group Based Policy https://tools.ietf.org/html/draft-smith-vxlan-group-policy-00 + vx.GBPExtension = data[0]&0x80 > 0 // 'G' bit per the group policy draft + vx.GBPDontLearn = data[1]&0x40 > 0 // 'D' bit - the egress VTEP MUST NOT learn the source address of the encapsulated frame. + vx.GBPApplied = data[1]&0x80 > 0 // 'A' bit - indicates that the group policy has already been applied to this packet. + vx.GBPGroupPolicyID = binary.BigEndian.Uint16(data[2:4]) // Policy ID as per the group policy draft + + // Layer information + const vxlanLength = 8 + vx.Contents = data[:vxlanLength] + vx.Payload = data[vxlanLength:] + + p.AddLayer(vx) + return p.NextDecoder(LinkTypeEthernet) +} + +// SerializeTo writes the serialized form of this layer into the +// SerializationBuffer, implementing gopacket.SerializableLayer. +// See the docs for gopacket.SerializableLayer for more info. +func (vx *VXLAN) SerializeTo(b gopacket.SerializeBuffer, opts gopacket.SerializeOptions) error { + bytes, err := b.PrependBytes(8) + if err != nil { + return err + } + + if vx.ValidIDFlag { + bytes[0] |= 0x08 + } + if vx.GBPExtension { + bytes[0] |= 0x80 + } + if vx.GBPDontLearn { + bytes[1] |= 0x40 + } + if vx.GBPApplied { + bytes[1] |= 0x80 + } + + binary.BigEndian.PutUint16(bytes[2:4], vx.GBPGroupPolicyID) + if vx.VNI >= 1<<24 { + return fmt.Errorf("Virtual Network Identifier = %x exceeds max for 24-bit uint", vx.VNI) + } + binary.BigEndian.PutUint32(bytes[4:8], vx.VNI<<8) + return nil +} -- cgit 1.2.3-korg