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-rw-r--r--vendor/github.com/google/gopacket/layers/vxlan.go94
1 files changed, 94 insertions, 0 deletions
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
+}