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-rw-r--r--vendor/github.com/google/gopacket/layers/udp.go120
1 files changed, 120 insertions, 0 deletions
diff --git a/vendor/github.com/google/gopacket/layers/udp.go b/vendor/github.com/google/gopacket/layers/udp.go
new file mode 100644
index 0000000..20f8c50
--- /dev/null
+++ b/vendor/github.com/google/gopacket/layers/udp.go
@@ -0,0 +1,120 @@
+// 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"
+ "fmt"
+ "github.com/google/gopacket"
+)
+
+// UDP is the layer for UDP headers.
+type UDP struct {
+ BaseLayer
+ SrcPort, DstPort UDPPort
+ Length uint16
+ Checksum uint16
+ sPort, dPort []byte
+ tcpipchecksum
+}
+
+// LayerType returns gopacket.LayerTypeUDP
+func (u *UDP) LayerType() gopacket.LayerType { return LayerTypeUDP }
+
+func (udp *UDP) DecodeFromBytes(data []byte, df gopacket.DecodeFeedback) error {
+ udp.SrcPort = UDPPort(binary.BigEndian.Uint16(data[0:2]))
+ udp.sPort = data[0:2]
+ udp.DstPort = UDPPort(binary.BigEndian.Uint16(data[2:4]))
+ udp.dPort = data[2:4]
+ udp.Length = binary.BigEndian.Uint16(data[4:6])
+ udp.Checksum = binary.BigEndian.Uint16(data[6:8])
+ udp.BaseLayer = BaseLayer{Contents: data[:8]}
+ switch {
+ case udp.Length >= 8:
+ hlen := int(udp.Length)
+ if hlen > len(data) {
+ df.SetTruncated()
+ hlen = len(data)
+ }
+ udp.Payload = data[8:hlen]
+ case udp.Length == 0: // Jumbogram, use entire rest of data
+ udp.Payload = data[8:]
+ default:
+ return fmt.Errorf("UDP packet too small: %d bytes", udp.Length)
+ }
+ 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 (u *UDP) SerializeTo(b gopacket.SerializeBuffer, opts gopacket.SerializeOptions) error {
+ var jumbo bool
+
+ payload := b.Bytes()
+ if _, ok := u.pseudoheader.(*IPv6); ok {
+ if len(payload)+8 > 65535 {
+ jumbo = true
+ }
+ }
+ bytes, err := b.PrependBytes(8)
+ if err != nil {
+ return err
+ }
+ binary.BigEndian.PutUint16(bytes, uint16(u.SrcPort))
+ binary.BigEndian.PutUint16(bytes[2:], uint16(u.DstPort))
+ if opts.FixLengths {
+ if jumbo {
+ u.Length = 0
+ } else {
+ u.Length = uint16(len(payload)) + 8
+ }
+ }
+ binary.BigEndian.PutUint16(bytes[4:], u.Length)
+ if opts.ComputeChecksums {
+ // zero out checksum bytes
+ bytes[6] = 0
+ bytes[7] = 0
+ csum, err := u.computeChecksum(b.Bytes(), IPProtocolUDP)
+ if err != nil {
+ return err
+ }
+ u.Checksum = csum
+ }
+ binary.BigEndian.PutUint16(bytes[6:], u.Checksum)
+ return nil
+}
+
+func (u *UDP) CanDecode() gopacket.LayerClass {
+ return LayerTypeUDP
+}
+
+// NextLayerType use the destination port to select the
+// right next decoder. It tries first to decode via the
+// destination port, then the source port.
+func (u *UDP) NextLayerType() gopacket.LayerType {
+ if lt := u.DstPort.LayerType(); lt != gopacket.LayerTypePayload {
+ return lt
+ }
+ return u.SrcPort.LayerType()
+}
+
+func decodeUDP(data []byte, p gopacket.PacketBuilder) error {
+ udp := &UDP{}
+ err := udp.DecodeFromBytes(data, p)
+ p.AddLayer(udp)
+ p.SetTransportLayer(udp)
+ if err != nil {
+ return err
+ }
+ return p.NextDecoder(udp.NextLayerType())
+}
+
+func (u *UDP) TransportFlow() gopacket.Flow {
+ return gopacket.NewFlow(EndpointUDPPort, u.sPort, u.dPort)
+}