diff options
Diffstat (limited to 'scripts/external_libs/dpkt-1.8.6/dpkt/ethernet.py')
| -rw-r--r-- | scripts/external_libs/dpkt-1.8.6/dpkt/ethernet.py | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/scripts/external_libs/dpkt-1.8.6/dpkt/ethernet.py b/scripts/external_libs/dpkt-1.8.6/dpkt/ethernet.py new file mode 100644 index 00000000..eca04868 --- /dev/null +++ b/scripts/external_libs/dpkt-1.8.6/dpkt/ethernet.py @@ -0,0 +1,140 @@ +# $Id: ethernet.py 65 2010-03-26 02:53:51Z dugsong $ + +"""Ethernet II, LLC (802.3+802.2), LLC/SNAP, and Novell raw 802.3, +with automatic 802.1q, MPLS, PPPoE, and Cisco ISL decapsulation.""" + +import struct +import dpkt, stp + +ETH_CRC_LEN = 4 +ETH_HDR_LEN = 14 + +ETH_LEN_MIN = 64 # minimum frame length with CRC +ETH_LEN_MAX = 1518 # maximum frame length with CRC + +ETH_MTU = (ETH_LEN_MAX - ETH_HDR_LEN - ETH_CRC_LEN) +ETH_MIN = (ETH_LEN_MIN - ETH_HDR_LEN - ETH_CRC_LEN) + +# Ethernet payload types - http://standards.ieee.org/regauth/ethertype +ETH_TYPE_PUP = 0x0200 # PUP protocol +ETH_TYPE_IP = 0x0800 # IP protocol +ETH_TYPE_ARP = 0x0806 # address resolution protocol +ETH_TYPE_AOE = 0x88a2 # AoE protocol +ETH_TYPE_CDP = 0x2000 # Cisco Discovery Protocol +ETH_TYPE_DTP = 0x2004 # Cisco Dynamic Trunking Protocol +ETH_TYPE_REVARP = 0x8035 # reverse addr resolution protocol +ETH_TYPE_8021Q = 0x8100 # IEEE 802.1Q VLAN tagging +ETH_TYPE_IPX = 0x8137 # Internetwork Packet Exchange +ETH_TYPE_IP6 = 0x86DD # IPv6 protocol +ETH_TYPE_PPP = 0x880B # PPP +ETH_TYPE_MPLS = 0x8847 # MPLS +ETH_TYPE_MPLS_MCAST = 0x8848 # MPLS Multicast +ETH_TYPE_PPPoE_DISC = 0x8863 # PPP Over Ethernet Discovery Stage +ETH_TYPE_PPPoE = 0x8864 # PPP Over Ethernet Session Stage +ETH_TYPE_LLDP = 0x88CC #Link Layer Discovery Protocol + +# MPLS label stack fields +MPLS_LABEL_MASK = 0xfffff000 +MPLS_QOS_MASK = 0x00000e00 +MPLS_TTL_MASK = 0x000000ff +MPLS_LABEL_SHIFT= 12 +MPLS_QOS_SHIFT = 9 +MPLS_TTL_SHIFT = 0 +MPLS_STACK_BOTTOM=0x0100 + +class Ethernet(dpkt.Packet): + __hdr__ = ( + ('dst', '6s', ''), + ('src', '6s', ''), + ('type', 'H', ETH_TYPE_IP) + ) + _typesw = {} + + def _unpack_data(self, buf): + if self.type == ETH_TYPE_8021Q: + self.tag, self.type = struct.unpack('>HH', buf[:4]) + buf = buf[4:] + elif self.type == ETH_TYPE_MPLS or \ + self.type == ETH_TYPE_MPLS_MCAST: + # XXX - skip labels (max # of labels is undefined, just use 24) + self.labels = [] + for i in range(24): + entry = struct.unpack('>I', buf[i*4:i*4+4])[0] + label = ((entry & MPLS_LABEL_MASK) >> MPLS_LABEL_SHIFT, \ + (entry & MPLS_QOS_MASK) >> MPLS_QOS_SHIFT, \ + (entry & MPLS_TTL_MASK) >> MPLS_TTL_SHIFT) + self.labels.append(label) + if entry & MPLS_STACK_BOTTOM: + break + self.type = ETH_TYPE_IP + buf = buf[(i + 1) * 4:] + try: + self.data = self._typesw[self.type](buf) + setattr(self, self.data.__class__.__name__.lower(), self.data) + except (KeyError, dpkt.UnpackError): + self.data = buf + + def unpack(self, buf): + dpkt.Packet.unpack(self, buf) + if self.type > 1500: + # Ethernet II + self._unpack_data(self.data) + elif self.dst.startswith('\x01\x00\x0c\x00\x00') or \ + self.dst.startswith('\x03\x00\x0c\x00\x00'): + # Cisco ISL + self.vlan = struct.unpack('>H', self.data[6:8])[0] + self.unpack(self.data[12:]) + elif self.data.startswith('\xff\xff'): + # Novell "raw" 802.3 + self.type = ETH_TYPE_IPX + self.data = self.ipx = self._typesw[ETH_TYPE_IPX](self.data[2:]) + else: + # 802.2 LLC + self.dsap, self.ssap, self.ctl = struct.unpack('BBB', self.data[:3]) + if self.data.startswith('\xaa\xaa'): + # SNAP + self.type = struct.unpack('>H', self.data[6:8])[0] + self._unpack_data(self.data[8:]) + else: + # non-SNAP + dsap = ord(self.data[0]) + if dsap == 0x06: # SAP_IP + self.data = self.ip = self._typesw[ETH_TYPE_IP](self.data[3:]) + elif dsap == 0x10 or dsap == 0xe0: # SAP_NETWARE{1,2} + self.data = self.ipx = self._typesw[ETH_TYPE_IPX](self.data[3:]) + elif dsap == 0x42: # SAP_STP + self.data = self.stp = stp.STP(self.data[3:]) + + def set_type(cls, t, pktclass): + cls._typesw[t] = pktclass + set_type = classmethod(set_type) + + def get_type(cls, t): + return cls._typesw[t] + get_type = classmethod(get_type) + +# XXX - auto-load Ethernet dispatch table from ETH_TYPE_* definitions +def __load_types(): + g = globals() + for k, v in g.iteritems(): + if k.startswith('ETH_TYPE_'): + name = k[9:] + modname = name.lower() + try: + mod = __import__(modname, g) + except ImportError: + continue + Ethernet.set_type(v, getattr(mod, name)) + +if not Ethernet._typesw: + __load_types() + +if __name__ == '__main__': + import unittest + + class EthTestCase(unittest.TestCase): + def test_eth(self): + s = '\x00\xb0\xd0\xe1\x80r\x00\x11$\x8c\x11\xde\x86\xdd`\x00\x00\x00\x00(\x06@\xfe\x80\x00\x00\x00\x00\x00\x00\x02\x11$\xff\xfe\x8c\x11\xde\xfe\x80\x00\x00\x00\x00\x00\x00\x02\xb0\xd0\xff\xfe\xe1\x80r\xcd\xd3\x00\x16\xffP\xd7\x13\x00\x00\x00\x00\xa0\x02\xff\xffg\xd3\x00\x00\x02\x04\x05\xa0\x01\x03\x03\x00\x01\x01\x08\n}\x18:a\x00\x00\x00\x00' + eth = Ethernet(s) + + unittest.main() |