| #! /usr/bin/env python |
| # RFC 7348 - Virtual eXtensible Local Area Network (VXLAN): |
| # A Framework for Overlaying Virtualized Layer 2 Networks over Layer 3 Networks |
| # http://tools.ietf.org/html/rfc7348 |
| # https://www.ietf.org/id/draft-ietf-nvo3-vxlan-gpe-02.txt |
| # |
| # VXLAN Group Policy Option: |
| # http://tools.ietf.org/html/draft-smith-vxlan-group-policy-00 |
| |
| from scapy.packet import Packet, bind_layers |
| from scapy.layers.l2 import Ether |
| from scapy.layers.inet import IP, UDP |
| from scapy.layers.inet6 import IPv6 |
| from scapy.fields import FlagsField, XByteField, ThreeBytesField, \ |
| ConditionalField, ShortField, ByteEnumField, X3BytesField |
| |
| _GP_FLAGS = ["R", "R", "R", "A", "R", "R", "D", "R"] |
| |
| |
| class VXLAN(Packet): |
| name = "VXLAN" |
| |
| fields_desc = [ |
| FlagsField("flags", 0x8, 8, |
| ['OAM', 'R', 'NextProtocol', 'Instance', |
| 'V1', 'V2', 'R', 'G']), |
| ConditionalField( |
| ShortField("reserved0", 0), |
| lambda pkt: pkt.flags.NextProtocol, |
| ), |
| ConditionalField( |
| ByteEnumField('NextProtocol', 0, |
| {0: 'NotDefined', |
| 1: 'IPv4', |
| 2: 'IPv6', |
| 3: 'Ethernet', |
| 4: 'NSH'}), |
| lambda pkt: pkt.flags.NextProtocol, |
| ), |
| ConditionalField( |
| ThreeBytesField("reserved1", 0), |
| lambda pkt: (not pkt.flags.G) and (not pkt.flags.NextProtocol), |
| ), |
| ConditionalField( |
| FlagsField("gpflags", 0, 8, _GP_FLAGS), |
| lambda pkt: pkt.flags.G, |
| ), |
| ConditionalField( |
| ShortField("gpid", 0), |
| lambda pkt: pkt.flags.G, |
| ), |
| X3BytesField("vni", 0), |
| XByteField("reserved2", 0), |
| ] |
| |
| # Use default linux implementation port |
| overload_fields = { |
| UDP: {'dport': 8472}, |
| } |
| |
| def mysummary(self): |
| if self.flags.G: |
| return self.sprintf("VXLAN (vni=%VXLAN.vni% gpid=%VXLAN.gpid%)") |
| else: |
| return self.sprintf("VXLAN (vni=%VXLAN.vni%)") |
| |
| bind_layers(UDP, VXLAN, dport=4789) # RFC standard vxlan port |
| bind_layers(UDP, VXLAN, dport=4790) # RFC standard vxlan-gpe port |
| bind_layers(UDP, VXLAN, dport=6633) # New IANA assigned port for use with NSH |
| bind_layers(UDP, VXLAN, dport=8472) # Linux implementation port |
| bind_layers(UDP, VXLAN, sport=4789) |
| bind_layers(UDP, VXLAN, sport=4790) |
| bind_layers(UDP, VXLAN, sport=6633) |
| bind_layers(UDP, VXLAN, sport=8472) |
| # By default, set both ports to the RFC standard |
| bind_layers(UDP, VXLAN, sport=4789, dport=4789) |
| |
| bind_layers(VXLAN, Ether) |
| bind_layers(VXLAN, IP, NextProtocol=1) |
| bind_layers(VXLAN, IPv6, NextProtocol=2) |
| bind_layers(VXLAN, Ether, flags=4, NextProtocol=0) |
| bind_layers(VXLAN, IP, flags=4, NextProtocol=1) |
| bind_layers(VXLAN, IPv6, flags=4, NextProtocol=2) |
| bind_layers(VXLAN, Ether, flags=4, NextProtocol=3) |