WIP GRE tunnel

1 files changed, 19 insertions, 0 deletions

diff --git a/pkg/tcpip/header/gre.go b/pkg/tcpip/header/gre.go
new file mode 100644
index 000000000..3d1cc97d9
--- /dev/null
+++ b/pkg/tcpip/header/gre.go
@@ -0,0 +1,19 @@
+package header
+
+import (
+        "encoding/binary"
+        
+	"gvisor.dev/gvisor/pkg/tcpip"
+)
+
+const (
+	greProtocolType  = 2
+)
+
+// GRE represents a GRE header stored in a byte array.
+type GRE []byte
+
+// SetLength sets the "length" field of the udp header.
+func (b GRE) SetProtocolType(protocol tcpip.NetworkProtocolNumber) {
+	binary.BigEndian.PutUint16(b[greProtocolType:], uint16(protocol))
+}