/
ethernet.py
1048 lines (923 loc) · 44.5 KB
/
ethernet.py
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'''
Created on 2015/7/30
:author: hubo
'''
from namedstruct import *
from namedstruct.namedstruct import rawtype as _rawtype
import array
import socket
ethertype = enum('ethertype', globals(), uint16,
ETHERTYPE_LOOP = 0x0060, # Ethernet Loopback packet
ETHERTYPE_PUP = 0x0200, # Xerox PUP packet
ETHERTYPE_PUPAT = 0x0201, # Xerox PUP Addr Trans packet
ETHERTYPE_IP = 0x0800, # Internet Protocol packet
ETHERTYPE_X25 = 0x0805, # CCITT X.25
ETHERTYPE_ARP = 0x0806, # Address Resolution packet
ETHERTYPE_BPQ = 0x08FF, # G8BPQ AX.25 Ethernet Packet [ NOT AN OFFICIALLY REGISTERED ID ]
ETHERTYPE_IEEEPUP = 0x0a00, # Xerox IEEE802.3 PUP packet
ETHERTYPE_IEEEPUPAT = 0x0a01, # Xerox IEEE802.3 PUP Addr Trans packet
ETHERTYPE_DEC = 0x6000, # DEC Assigned proto
ETHERTYPE_DNA_DL = 0x6001, # DEC DNA Dump/Load
ETHERTYPE_DNA_RC = 0x6002, # DEC DNA Remote Console
ETHERTYPE_DNA_RT = 0x6003, # DEC DNA Routing
ETHERTYPE_LAT = 0x6004, # DEC LAT
ETHERTYPE_DIAG = 0x6005, # DEC Diagnostics
ETHERTYPE_CUST = 0x6006, # DEC Customer use
ETHERTYPE_SCA = 0x6007, # DEC Systems Comms Arch
ETHERTYPE_TEB = 0x6558, # Trans Ether Bridging
ETHERTYPE_RARP = 0x8035, # Reverse Addr Res packet
ETHERTYPE_ATALK = 0x809B, # Appletalk DDP
ETHERTYPE_AARP = 0x80F3, # Appletalk AARP
ETHERTYPE_8021Q = 0x8100, # 802.1Q VLAN Extended Header
ETHERTYPE_IPX = 0x8137, # IPX over DIX
ETHERTYPE_IPV6 = 0x86DD, # IPv6 over bluebook
ETHERTYPE_PAUSE = 0x8808, # IEEE Pause frames. See 802.3 31B
ETHERTYPE_SLOW = 0x8809, # Slow Protocol. See 802.3ad 43B
ETHERTYPE_WCCP = 0x883E, # Web-cache coordination protocol defined in draft-wilson-wrec-wccp-v2-00.txt
ETHERTYPE_PPP_DISC = 0x8863, # PPPoE discovery messages
ETHERTYPE_PPP_SES = 0x8864, # PPPoE session messages
ETHERTYPE_MPLS_UC = 0x8847, # MPLS Unicast traffic
ETHERTYPE_MPLS_MC = 0x8848, # MPLS Multicast traffic
ETHERTYPE_ATMMPOA = 0x884c, # MultiProtocol Over ATM
ETHERTYPE_ATMFATE = 0x8884, # Frame-based ATM Transport over Ethernet
ETHERTYPE_PAE = 0x888E, # Port Access Entity (IEEE 802.1X)
ETHERTYPE_AOE = 0x88A2, # ATA over Ethernet
ETHERTYPE_8021QS = 0x88A8, # 8021.Q Server VLAN Extended Header
ETHERTYPE_TIPC = 0x88CA, # TIPC
ETHERTYPE_1588 = 0x88F7, # IEEE 1588 Timesync
ETHERTYPE_FCOE = 0x8906, # Fibre Channel over Ethernet
ETHERTYPE_TDLS = 0x890D, # TDLS
ETHERTYPE_FIP = 0x8914, # FCoE Initialization Protocol
ETHERTYPE_NSH = 0x894f,
ETHERTYPE_EDSA = 0xDADA, # Ethertype DSA [ NOT AN OFFICIALLY REGISTERED ID ]
ETHERTYPE_AF_IUCV = 0xFBFB # IBM af_iucv [ NOT AN OFFICIALLY REGISTERED ID ]
)
arp_op_code = enum('arp_op_code', globals(), uint16,
ARPOP_REQUEST = 1, # ARP request.
ARPOP_REPLY = 2, # ARP reply.
ARPOP_RREQUEST = 3, # RARP request.
ARPOP_RREPLY = 4, # RARP reply.
ARPOP_InREQUEST = 8, # InARP request.
ARPOP_InREPLY = 9, # InARP reply.
ARPOP_NAK = 10 # (ATM)ARP NAK.
)
ip_protocol = enum('ip_protocol', globals(), uint8, False,
IPPROTO_IP = 0, # Dummy protocol for TCP
IPPROTO_ICMP = 1, # Internet Control Message Protocol
IPPROTO_IGMP = 2, # Internet Group Management Protocol
IPPROTO_IPIP = 4, # IPIP tunnels (older KA9Q tunnels use 94)
IPPROTO_TCP = 6, # Transmission Control Protocol
IPPROTO_EGP = 8, # Exterior Gateway Protocol
IPPROTO_PUP = 12, # PUP protocol
IPPROTO_UDP = 17, # User Datagram Protocol
IPPROTO_IDP = 22, # XNS IDP protocol
IPPROTO_DCCP = 33, # Datagram Congestion Control Protocol
IPPROTO_RSVP = 46, # RSVP protocol
IPPROTO_GRE = 47, # Cisco GRE tunnels (rfc 1701,1702)
IPPROTO_IPV6 = 41, # IPv6-in-IPv4 tunnelling
IPPROTO_ESP = 50, # Encapsulation Security Payload protocol
IPPROTO_AH = 51, # Authentication Header protocol
IPPROTO_BEETPH = 94, # IP option pseudo header for BEET
IPPROTO_PIM = 103, # Protocol Independent Multicast
IPPROTO_COMP = 108, # Compression Header protocol
IPPROTO_SCTP = 132, # Stream Control Transport Protocol
IPPROTO_UDPLITE = 136, # UDP-Lite (RFC 3828)
IPPROTO_RAW = 255 # Raw IP packets
)
ETH_ALEN = 6
mac_addr = uint8[ETH_ALEN]
mac_addr.formatter = lambda x: ':'.join('%02x' % (n,) for n in x)
def _create_mac_addr(addr = None):
if addr is None:
return [0] * ETH_ALEN
else:
mac_array = [int(v,16) for v in addr.split(':')]
return (mac_array + [0] * (ETH_ALEN - len(mac_array)))[:ETH_ALEN]
mac_addr.new = _create_mac_addr
mac_addr_bytes = prim(str(ETH_ALEN) + 's', 'mac_addr_bytes')
mac_addr_bytes.formatter = lambda x: ':'.join('%02x' % (c,) for c in bytearray(x.ljust(6, b'\x00')))
def _create_mac_addr_bytes(addr = None):
if addr is None:
return b'\x00' * ETH_ALEN
else:
return mac_addr.tobytes(mac_addr(addr))
mac_addr_bytes.new = _create_mac_addr_bytes
ip4_addr = prim('I', 'ip4_addr')
import socket as _socket
ip4_addr.formatter = lambda x: _socket.inet_ntoa(ip4_addr.tobytes(x))
def _ip4_addr_new(ip_addr = None):
if ip_addr is None:
return 0
else:
return ip4_addr.create(_socket.inet_aton(ip_addr))
ip4_addr.new = _ip4_addr_new
ip4_addr_bytes = prim('4s', 'ip4_addr_bytes')
ip4_addr_bytes.formatter = lambda x: _socket.inet_ntoa(x.ljust(4, b'\x00'))
def _ip4_addr_bytes_new(ip_addr = None):
if ip_addr is None:
return b'\x00\x00\x00\x00'
else:
return _socket.inet_aton(ip_addr)
ip4_addr_bytes.new = _ip4_addr_bytes_new
ip6_addr = uint8[16]
if hasattr(_socket, 'inet_ntop'):
ip6_addr.formatter = lambda x: _socket.inet_ntop(_socket.AF_INET6, ip6_addr.tobytes(x.ljust(16, b'\x00')))
if hasattr(_socket, 'inet_pton'):
def _ip6_addr_new(ip_addr = None):
if ip_addr is None:
return [0] * 16
else:
return ip6_addr.create(_socket.inet_pton(_socket.AF_INET6, ip_addr))
else:
def _ip6_addr_new(ip_addr = None):
if ip_addr is None:
return [0] * 16
else:
fp, sep, lp = ip_addr.partition('::')
if not sep:
return [int(v,16) for v in fp.split(':')]
else:
fp_l = [int(v,16) for v in fp.split(':')]
lp_l = [int(v,16) for v in lp.split(':')]
if len(fp_l) + len(lp_l) > 8:
raise ValueError('Illegal IPv6 address')
else:
return fp_l + [0] * (8 - len(fp_l) - len(lp_l)) + lp_l
ip6_addr.new = _ip6_addr_new
ip6_addr_bytes = prim('16s', 'ip6_addr')
if hasattr(_socket, 'inet_ntop'):
ip6_addr.formatter = lambda x: _socket.inet_ntop(_socket.AF_INET6, x)
if hasattr(_socket, 'inet_pton'):
def _ip6_addr_bytes_new(ip_addr = None):
if ip_addr is None:
return b'\x00' * 16
else:
return _socket.inet_pton(_socket.AF_INET6, ip_addr)
else:
def _ip6_addr_bytes_new(ip_addr = None):
if ip_addr is None:
return b'\x00' * 16
else:
return ip6_addr.tobytes(_ip6_addr_new(ip_addr))
ip6_addr_bytes.new = _ip6_addr_bytes_new
ethernet_l2 = nstruct((mac_addr,'dl_dst'),
(mac_addr,'dl_src'),
(ethertype,'dl_type'),
name='ethernet_l2',
padding = 1,
size = lambda x: 18 if x.dl_type == ETHERTYPE_8021Q else
22 if x.dl_type == ETHERTYPE_8021QS else
14
)
ethernet_l2_8021q = nstruct((uint16, 'vlan_tci'),
(ethertype, 'dl_type2'),
base = ethernet_l2,
name = "ethernet_l2_8021q",
criteria = lambda x: x.dl_type == ETHERTYPE_8021Q,
init = packvalue(ETHERTYPE_8021Q, 'dl_type')
)
ethernet_l2_8021ad = nstruct((uint16, 'svlan_tci'),
(ethertype, 'dl_type3'),
(uint16, 'vlan_tci'),
(ethertype, 'dl_type2'),
base = ethernet_l2,
name = 'ethernet_l2_8021ad',
criteria = lambda x: x.dl_type == ETHERTYPE_8021QS,
init = lambda x: (packvalue(ETHERTYPE_8021QS, 'dl_type')(x),
packvalue(ETHERTYPE_8021Q, 'dl_type3')(x))
)
def dl_type(packet):
if packet.dl_type == ETHERTYPE_8021Q:
return packet.dl_type2
else:
return packet.dl_type
def vlan_vid(packet):
if packet.dl_type == ETHERTYPE_8021Q:
return (packet.vlan_tci & 0xfff) | 0x1000
else:
return 0
def vlan_pcp(packet):
if packet.dl_type == ETHERTYPE_8021Q:
return (packet.vlan_tci >> 13)
else:
return 0
def create_vlan_tci(vid, pcp = 0):
return ((pcp & 0x7) << 13) | 0x1000 | (vid & 0xfff)
ethernet_l3 = nstruct((ethernet_l2,),
name = "ethernet_l3",
padding = 1,
classifier = lambda x: x.dl_type2 if x.dl_type == ETHERTYPE_8021Q or x.dl_type == ETHERTYPE_8021QS else x.dl_type)
arp_payload = nstruct(
(uint16,'arp_hwtype'),
(uint16,'arp_proto'),
(uint8,'hw_len'),
(uint8,'proto_len'),
(arp_op_code,'arp_op'),
(mac_addr,'arp_sha'),
(ip4_addr,'arp_spa'),
(mac_addr,'arp_tha'),
(ip4_addr,'arp_tpa'),
name = 'arp_payload',
padding = 1,
init = lambda x: (packvalue(1, 'arp_hwtype')(x),
packvalue(ETHERTYPE_IP, 'arp_proto')(x),
packvalue(6, 'hw_len')(x),
packvalue(4, 'proto_len')(x))
)
def create_packet(packettype, vid = None, pcp = 0, svid = None, spcp = 0, *args, **kwargs):
if svid is not None:
dl_type = packettype().dl_type
return packettype((ethernet_l2, ethernet_l2_8021ad), *args,
dl_type2 = dl_type, vlan_tci = create_vlan_tci(vid, pcp),
svlan_tci = create_vlan_tci(svid, spcp),
**kwargs)
elif vid is not None:
dl_type = packettype().dl_type
return packettype((ethernet_l2, ethernet_l2_8021q), *args,
dl_type2 = dl_type, vlan_tci = create_vlan_tci(vid, pcp),
**kwargs)
else:
return packettype(*args, **kwargs)
arp_packet = nstruct((arp_payload,),
base = ethernet_l3,
classifyby = (ETHERTYPE_ARP,),
name = 'arp_packet',
init = packvalue(ETHERTYPE_ARP, 'dl_type')
)
def checksum(data):
if len(data) % 2:
data += b'\x00'
s = sum(array.array('H',data))
s = (s & 0xffff) + (s >> 16)
s += (s >> 16)
return _socket.ntohs(~s & 0xffff)
def checksum2(*checksums):
s = sum(checksums)
s = (s & 0xffff) + (s >> 16)
s += (s >> 16)
return (s & 0xffff)
def ip4_checksum(x):
data = x._tobytes(True)
return checksum(data)
def _prepack_ip4_header(x):
size = len(x)
if size > 60:
raise ValueError('IP header is too large')
x.version_length = 0x40 | (size // 4)
ip_tos = enum('ip_tos', globals(), uint8, True,
IPTOS_ECN_ECT1 = 0x01,
IPTOS_ECN_ECT0 = 0x02,
IPTOS_ECN_CE = 0x03,
IPTOS_DSCP_AF11 = 0x28,
IPTOS_DSCP_AF12 = 0x30,
IPTOS_DSCP_AF13 = 0x38,
IPTOS_DSCP_AF21 = 0x48,
IPTOS_DSCP_AF22 = 0x50,
IPTOS_DSCP_AF23 = 0x58,
IPTOS_DSCP_AF31 = 0x68,
IPTOS_DSCP_AF32 = 0x70,
IPTOS_DSCP_AF33 = 0x78,
IPTOS_DSCP_AF41 = 0x88,
IPTOS_DSCP_AF42 = 0x90,
IPTOS_DSCP_AF43 = 0x98,
IPTOS_DSCP_EF = 0xb8,
IPTOS_CLASS_CS1 = 0x20,
IPTOS_CLASS_CS2 = 0x40,
IPTOS_CLASS_CS3 = 0x60,
IPTOS_CLASS_CS4 = 0x80,
IPTOS_CLASS_CS5 = 0xa0,
IPTOS_CLASS_CS6 = 0xc0,
IPTOS_CLASS_CS7 = 0xe0
)
IPTOS_ECN_NOT_ECT = 0x00
IPTOS_ECN_MASK = 0x03
IPTOS_DSCP_MASK = 0xfc
IPTOS_CLASS_MASK = 0xe0
IPTOS_CLASS_CS0 = 0x00
ip_frag_offset = enum("ip_frag_offset", globals(), uint16, True,
IP_RF = 0x8000,
IP_DF = 0x4000,
IP_MF = 0x2000
)
IP_OFFMASK = 0x1fff
IP_FRAG_ANY = (1 << 0) # Is this a fragment?
IP_FRAG_LATER = (1 << 1) # Is this a fragment with nonzero offset?
def ip_frag(packet):
'''
Not fragments:
ip_frag(packet) == 0
not ip_frag(packet)
First packet of fragments:
ip_frag(packet) == IP_FRAG_ANY
Not first packet of fragments:
ip_frag(packet) & IP_FRAG_LATER
All fragments:
ip_frag(packet) & IP_FRAG_ANY
'''
return ((packet.frag_off & IP_OFFMASK) and IP_FRAG_LATER) | ((packet.frag_off & (IP_OFFMASK | IP_MF)) and IP_FRAG_ANY)
ip4_header = nstruct(
# 4bit version + 4bit length
(uint8,'version_length'),
(ip_tos,'tos'),
(uint16,'total_len'),
(uint16,'identifier'),
# 3bit frag + 13bit offset
(ip_frag_offset,'frag_off'),
(uint8,'ttl'),
(ip_protocol,'proto'),
(uint16,'checksum'),
(ip4_addr,'ip_src'),
(ip4_addr,'ip_dst'),
(raw, 'options'),
padding = 4,
name = 'ip4_header',
size = lambda x: (x.version_length & 0xf) * 4,
prepack = _prepack_ip4_header,
init = packvalue(0x45, 'version_length')
)
def calcuate_ip4_checksum(x):
x.checksum = 0
x.checksum = ip4_checksum(x._get_embedded(ip4_header)) or 0xffff
def _prepack_ip4_payload(x):
x.total_len = x._realsize()
calcuate_ip4_checksum(x)
ip4_packet = nstruct((ip4_header,),
(raw, 'payload'),
base = ethernet_l3,
classifyby = (ETHERTYPE_IP,),
name = 'ip4_packet',
init = packvalue(ETHERTYPE_IP, 'dl_type'),
prepack = calcuate_ip4_checksum
)
# IP Packet without an Ethernet header
ip4_payload = nstruct((ip4_header,),
name = "ip4_payload",
padding = 1,
size = lambda x: x.total_len,
prepack = _prepack_ip4_payload
)
ip4_partial_payload = nstruct((ip4_header,),
name = "ip4_partial_payload",
padding = 1,
prepack = calcuate_ip4_checksum
)
ip4_payload_fragment = nstruct((raw, 'payload'),
base = ip4_payload,
criteria = lambda x: ip_frag(x) & IP_FRAG_LATER,
name = "ip4_payload_fragment"
)
ip4_partial_payload_fragment = nstruct((raw, 'payload'),
base = ip4_partial_payload,
criteria = lambda x: ip_frag(x) & IP_FRAG_LATER,
name = "ip4_partial_payload_fragment"
)
tcp_header_min = nstruct((uint16, 'sport'),
(uint16, 'dport'),
(uint32, 'seq'),
name = 'tcp_header_min',
padding = 1
)
tcp_flags = enum('tcp_flags', globals(), uint8, True,
TH_FIN = 0x01,
TH_SYN = 0x02,
TH_RST = 0x04,
TH_PUSH = 0x08,
TH_ACK = 0x10,
TH_URG = 0x20
)
def _pack_tcp_header_size(x):
x.data_offset = ((len(x) // 4) << 4)
tcp_option_kind = enum('tcp_option_kind', globals(), uint8,
TCPOPT_EOL = 0,
TCPOPT_NOP = 1,
TCPOPT_MAXSEG = 2,
TCPOPT_WINDOW = 3,
TCPOPT_SACK_PERMITTED = 4,
TCPOPT_SACK = 5,
TCPOPT_TIMESTAMP = 8
)
_tcp_option_header = nstruct((tcp_option_kind, 'kind'),
name = "tcp_option_header",
padding = 1,
size = lambda x: 1 if (x.kind == TCPOPT_EOL or x.kind == TCPOPT_NOP) else 2
)
_tcp_option_header_length = nstruct((uint8, 'length'),
name = "tcp_option_header_length",
base = _tcp_option_header,
criteria = lambda x: x.kind != TCPOPT_EOL and x.kind != TCPOPT_NOP
)
def _prepack_tcp_option(x):
s = x._realsize()
if s > 1:
x.length = s
tcp_option = nstruct((_tcp_option_header,),
name = "tcp_option",
padding = 1,
size = lambda x: 1 if (x.kind == TCPOPT_EOL or x.kind == TCPOPT_NOP) else x.length,
prepack = _prepack_tcp_option
)
def _init_tcp_option(kind):
def _init_func(x):
x._replace_embedded_type(_tcp_option_header, _tcp_option_header_length)
x.kind = kind
return _init_func
tcp_option_maxseg = nstruct((uint16, 'mss'),
name = 'tcp_option_maxseg',
base = tcp_option,
criteria = lambda x: x.kind == TCPOPT_MAXSEG,
init = _init_tcp_option(TCPOPT_MAXSEG)
)
tcp_option_window = nstruct((uint8, 'shift_cnt'),
name = 'tcp_option_window',
base = tcp_option,
criteria = lambda x: x.kind == TCPOPT_WINDOW,
init = _init_tcp_option(TCPOPT_WINDOW)
)
tcp_option_sack = nstruct((uint32[2][0], 'edges'),
name = 'tcp_option_sack',
base = tcp_option,
criteria = lambda x: x.kind == TCPOPT_SACK,
init = _init_tcp_option(TCPOPT_SACK)
)
tcp_option_timestamp = nstruct((uint32, 'tsval'),
(uint32, 'tsecr'),
name = 'tcp_option_timestamp',
base = tcp_option,
criteria = lambda x: x.kind == TCPOPT_TIMESTAMP,
init = _init_tcp_option(TCPOPT_TIMESTAMP))
def _format_tcp_options(x):
# Parse tcp options
options = tcp_option[0].create(x)
result = []
for o in options:
od = dump(o, dumpextra = True, typeinfo = DUMPTYPE_NONE)
anyvalue = False
for k,v in od.items():
if k not in ('kind', 'length') and not k.startswith('_'):
result.append(k + ': ' + repr(v))
anyvalue = True
if '_extra' in od:
result.append(str(od['kind']) + ': ' + repr(od['_extra']))
anyvalue = True
if not anyvalue and o.kind != TCPOPT_EOL and o.kind != TCPOPT_NOP:
result.append(od['kind'])
return ', '.join(result)
_tcp_option_raw = _rawtype()
_tcp_option_raw.formatter = _format_tcp_options
tcp_header = nstruct((tcp_header_min,),
(uint32, 'ack'),
(uint8, 'data_offset'),
(tcp_flags, 'tcp_flags'),
(uint16, 'tcp_win'),
(uint16, 'tcp_sum'),
(uint16, 'tcp_urp'),
(_tcp_option_raw, 'tcp_options'),
name = 'tcp_header',
padding = 4,
size = lambda x: (x.data_offset >> 4) * 4,
prepack = _pack_tcp_header_size
)
tcp_payload = nstruct((tcp_header,),
(raw, 'data'),
name = "tcp_payload",
padding = 1
)
ip4_pseudo_header = nstruct((ip4_addr, 'ip_src'),
(ip4_addr, 'ip_dst'),
(uint8,),
(ip_protocol, 'protocol'),
(uint16, 'length'),
name = "ip4_pseudo_header",
padding = 1
)
def tp4_checksum(payload, src, dst, protocol = IPPROTO_TCP):
if hasattr(payload, '_tobytes'):
data = payload._tobytes(True)
else:
data = payload
return checksum2(checksum(ip4_pseudo_header(ip_src = src, ip_dst = dst, length = len(data), protocol = protocol)._tobytes()), checksum(data))
def _prepack_tcp4_payload(x):
x.tcp_sum = 0
x.tcp_sum = tp4_checksum(x, x.ip_src, x.ip_dst, IPPROTO_TCP) or 0xffff
_tcp_payload_ip4 = nstruct((tcp_payload,),
name = "_tcp_payload_ip4",
prepack = _prepack_tcp4_payload,
padding = 1,
lastextra = True
)
ip4_tcp_payload = nstruct((_tcp_payload_ip4,),
name = "ip4_tcp_payload",
base = ip4_payload,
criteria = lambda x: not ip_frag(x) and x.proto == IPPROTO_TCP,
lastextra = True,
init = packvalue(IPPROTO_TCP, 'proto'),
)
tcp_bestparse = nstruct((tcp_header_min,),
name = "tcp_bestparse",
padding = 1)
tcp_bestparse_min = nstruct((raw, 'otherpayload'),
base = tcp_bestparse,
name = "tcp_bestparse_min",
criteria = lambda x: x._realsize() < 20
)
tcp_bestparse_header = nstruct((uint32, 'ack'),
(uint8, 'data_offset'),
(tcp_flags, 'tcp_flags'),
(uint16, 'tcp_win'),
(uint16, 'tcp_sum'),
(uint16, 'tcp_urp'),
base = tcp_bestparse,
name = "tcp_bestparse_header",
criteria = lambda x: x._realsize() >= 20,
init = packvalue(5 << 4, 'data_offset')
)
tcp_bestparse_partial = nstruct((raw, 'otherpayload'),
base = tcp_bestparse_header,
name = "tcp_bestparse_partial",
criteria = lambda x: x._realsize() < (x.data_offset >> 4) * 4
)
_tcp_bestparse_full_options = nstruct((_tcp_option_raw, 'tcp_options'),
name = "_tcp_bestparse_full_options",
size = lambda x: max((x.data_offset >> 4) * 4 - 20, 0),
padding = 4,
prepack = packexpr(lambda x: ((len(x) // 4) << 4) + 5, 'data_offset')
)
tcp_bestparse_full = nstruct((_tcp_bestparse_full_options,),
(raw, 'data'),
base = tcp_bestparse_header,
name = "tcp_bestparse_full",
criteria = lambda x: x._realsize() >= (x.data_offset >> 4) * 4
)
ip4_tcp_fragment_payload = nstruct((tcp_bestparse,),
name = "ip4_tcp_fragment_payload",
base = ip4_payload,
criteria = lambda x: ip_frag(x) == IP_FRAG_ANY and x.proto == IPPROTO_TCP,
init = packvalue(IPPROTO_TCP, 'proto'),
lastextra = True
)
ip4_tcp_partial_payload = nstruct((tcp_bestparse,),
name = "ip4_tcp_partial_payload",
base = ip4_partial_payload,
criteria = lambda x: not (ip_frag(x) & IP_FRAG_LATER) and x.proto == IPPROTO_TCP,
init = packvalue(IPPROTO_TCP, 'proto'),
lastextra = True
)
udp_header = nstruct((uint16, 'sport'),
(uint16, 'dport'),
(uint16, 'udp_len'),
(uint16, 'udp_sum'),
name = "udp_header",
padding = 1
)
udp_payload = nstruct((udp_header,),
(raw, 'data'),
name = "udp_payload",
padding = 1,
prepack = packrealsize('udp_len')
)
def _prepack_udp4_payload(x):
x.udp_sum = 0
x.udp_sum = tp4_checksum(x, x.ip_src, x.ip_dst, IPPROTO_UDP) or 0xffff
_udp_payload_ip4 = nstruct((udp_payload,),
name = "_udp_payload_ip4",
prepack = _prepack_udp4_payload,
padding = 1,
lastextra = True
)
ip4_udp_payload = nstruct((_udp_payload_ip4,),
name = "ip4_udp_payload",
base = ip4_payload,
criteria = lambda x: not ip_frag(x) and x.proto == IPPROTO_UDP,
lastextra = True,
init = packvalue(IPPROTO_UDP, 'proto')
)
ip4_udp_fragment_payload = nstruct((udp_header,),
(raw, 'data'),
name = "ip4_udp_fragment_payload",
base = ip4_payload,
criteria = lambda x: ip_frag(x) == IP_FRAG_ANY and x.proto == IPPROTO_UDP,
init = packvalue(IPPROTO_UDP, 'proto')
)
ip4_udp_partial_payload = nstruct((udp_header,),
(raw, 'data'),
name = "ip4_udp_partial_payload",
base = ip4_partial_payload,
criteria = lambda x: not (ip_frag(x) & IP_FRAG_LATER) and x.proto == IPPROTO_UDP,
init = packvalue(IPPROTO_UDP, 'proto')
)
icmp_type = enum('icmp_type', globals(), uint8,
ICMP_ECHOREPLY = 0, # Echo Reply
ICMP_DEST_UNREACH = 3, # Destination Unreachable
ICMP_SOURCE_QUENCH = 4, # Source Quench
ICMP_REDIRECT = 5, # Redirect (change route)
ICMP_ECHO = 8, # Echo Request
ICMP_TIME_EXCEEDED = 11, # Time Exceeded
ICMP_PARAMETERPROB = 12, # Parameter Problem
ICMP_TIMESTAMP = 13, # Timestamp Request
ICMP_TIMESTAMPREPLY = 14, # Timestamp Reply
ICMP_INFO_REQUEST = 15, # Information Request
ICMP_INFO_REPLY = 16, # Information Reply
ICMP_ADDRESS = 17, # Address Mask Request
ICMP_ADDRESSREPLY = 18 # Address Mask Reply
)
icmp_code_unreach = enum('icmp_code_unreach', globals(), uint8,
ICMP_NET_UNREACH = 0, # Network Unreachable
ICMP_HOST_UNREACH = 1, # Host Unreachable
ICMP_PROT_UNREACH = 2, # Protocol Unreachable
ICMP_PORT_UNREACH = 3, # Port Unreachable
ICMP_FRAG_NEEDED = 4, # Fragmentation Needed/DF set
ICMP_SR_FAILED = 5, # Source Route failed
ICMP_NET_UNKNOWN = 6,
ICMP_HOST_UNKNOWN = 7,
ICMP_HOST_ISOLATED = 8,
ICMP_NET_ANO = 9,
ICMP_HOST_ANO = 10,
ICMP_NET_UNR_TOS = 11,
ICMP_HOST_UNR_TOS = 12,
ICMP_PKT_FILTERED = 13, # Packet filtered
ICMP_PREC_VIOLATION = 14, # Precedence violation
ICMP_PREC_CUTOFF = 15 # Precedence cut off
)
icmp_code_redirect = enum('icmp_code_redirect', globals(), uint8,
ICMP_REDIR_NET = 0, # Redirect Net
ICMP_REDIR_HOST = 1, # Redirect Host
ICMP_REDIR_NETTOS = 2, # Redirect Net for TOS
ICMP_REDIR_HOSTTOS = 3 # Redirect Host for TOS
)
icmp_code_te = enum('icmp_code_te', globals(), uint8,
ICMP_EXC_TTL = 0, # TTL count exceeded
ICMP_EXC_FRAGTIME = 1 # Fragment Reass time exceeded
)
icmp_header = nstruct((icmp_type, 'icmp_type'),
(uint8, 'icmp_code'),
(uint16, 'icmp_sum'),
name = "icmp_header",
padding = 1
)
icmp_bestparse = nstruct((icmp_header,),
name = "icmp_bestparse",
classifier = lambda x: x.icmp_type,
padding = 1
)
icmp_unreach = nstruct((uint32,),
(raw, 'data'),
classifyby = (ICMP_DEST_UNREACH,),
name = "icmp_unreach",
base = icmp_bestparse,
init = packvalue(ICMP_DEST_UNREACH, 'icmp_type'),
extend = {"icmp_code": icmp_code_unreach}
)
icmp_te = nstruct((uint32,),
(raw, 'data'),
classifyby = (ICMP_TIME_EXCEEDED,),
name = "icmp_te",
base = icmp_bestparse,
init = packvalue(ICMP_TIME_EXCEEDED, 'icmp_type'),
extend = {"icmp_code": icmp_code_te}
)
icmp_parameter_prob = nstruct((uint8, 'icmp_pointer'),
(uint8[3],),
(raw, 'data'),
classifyby = (ICMP_PARAMETERPROB,),
name = 'icmp_parameter_prob',
base = icmp_bestparse,
init = packvalue(ICMP_PARAMETERPROB, 'icmp_type')
)
icmp_source_quench = nstruct((uint32,),
(raw, 'data'),
classifyby = (ICMP_SOURCE_QUENCH,),
name = 'icmp_source_quench',
base = icmp_bestparse,
init = packvalue(ICMP_SOURCE_QUENCH, 'icmp_type')
)
icmp_redirect = nstruct((uint32, 'gateway'),
(raw, 'data'),
classifyby = (ICMP_REDIRECT,),
name = 'icmp_redirect',
base = icmp_bestparse,
init = packvalue(ICMP_REDIRECT, 'icmp_type'),
extend = {"icmp_code": icmp_code_redirect}
)
icmp_echo = nstruct((uint16, 'icmp_id'),
(uint16, 'icmp_seq'),
(raw, 'data'),
classifyby = (ICMP_ECHO, ICMP_ECHOREPLY),
name = "icmp_echo",
base = icmp_bestparse,
init = packvalue(ICMP_ECHO, 'icmp_type')
)
icmp_timestamp = nstruct((uint16, 'icmp_id'),
(uint16, 'icmp_seq'),
classifyby = (ICMP_TIMESTAMP, ICMP_TIMESTAMPREPLY),
name = "icmp_timestamp",
base = icmp_bestparse,
init = packvalue(ICMP_TIMESTAMP, 'icmp_type')
)
icmp_timestamp_partial = nstruct((raw, 'otherpayload'),
name = "icmp_timestamp_partial",
base = icmp_timestamp,
criteria = lambda x: x._realsize() < 20
)
icmp_timestamp_full = nstruct((uint32, 'orig_timestamp'),
(uint32, 'recv_timestamp'),
(uint32, 'trans_timestamp'),
name = "icmp_timestamp_full",
base = icmp_timestamp,
criteria = lambda x: x._realsize() >= 20
)
icmp_info = nstruct((uint16, 'icmp_id'),
(uint16, 'icmp_seq'),
classifyby = (ICMP_INFO_REQUEST, ICMP_INFO_REPLY),
name = "icmp_info",
base = icmp_bestparse,
init = packvalue(ICMP_INFO_REQUEST, 'icmp_type')
)
def _prepack_icmp_payload(x):
x.icmp_sum = 0
x.icmp_sum = checksum(x._tobytes(True)) or 0xffff
_icmp_payload_ip4 = nstruct((icmp_bestparse,),
name = "_icmp_payload_ip4",
prepack = _prepack_icmp_payload,
padding = 1,
lastextra = True
)
ip4_icmp_payload = nstruct((_icmp_payload_ip4,),
name = "ip4_icmp_payload",
base = ip4_payload,
criteria = lambda x: not ip_frag(x) and x.proto == IPPROTO_ICMP,
lastextra = True,
init = packvalue(IPPROTO_ICMP, 'proto')
)
ip4_icmp_fragment_payload = nstruct((icmp_bestparse,),
name = "ip4_icmp_fragment_payload",
base = ip4_payload,
criteria = lambda x: ip_frag(x) == IP_FRAG_ANY and x.proto == IPPROTO_ICMP,
lastextra = True,
init = packvalue(IPPROTO_ICMP, 'proto')
)
ip4_icmp_partial_payload = nstruct((icmp_bestparse,),
name = "ip4_icmp_partial_payload",
base = ip4_partial_payload,
criteria = lambda x: not (ip_frag(x) & IP_FRAG_LATER) and x.proto == IPPROTO_ICMP,
lastextra = True,
init = packvalue(IPPROTO_ICMP, 'proto')
)
ethernet_l4 = nstruct((ethernet_l2,),
name = "ethernet_l4",
padding = 1,
classifier = lambda x: x.dl_type2 if x.dl_type == ETHERTYPE_8021Q or x.dl_type == ETHERTYPE_8021QS else x.dl_type)
ethernet_l7 = nstruct((ethernet_l2,),
name = "ethernet_l7",
padding = 1,
classifier = lambda x: x.dl_type2 if x.dl_type == ETHERTYPE_8021Q or x.dl_type == ETHERTYPE_8021QS else x.dl_type)
arp_packet_l4 = nstruct((arp_payload,),
base = ethernet_l4,
classifyby = (ETHERTYPE_ARP,),
name = 'arp_packet_l4',
init = packvalue(ETHERTYPE_ARP, 'dl_type'),
lastextra = True
)
arp_packet_l7 = nstruct((arp_payload,),
base = ethernet_l7,
classifyby = (ETHERTYPE_ARP,),
name = 'arp_packet_l7',
init = packvalue(ETHERTYPE_ARP, 'dl_type'),
lastextra = True
)
ip4_packet_l4 = nstruct((ip4_partial_payload,),
base = ethernet_l4,
classifyby = (ETHERTYPE_IP,),
name = 'ip4_packet_l4',
init = packvalue(ETHERTYPE_IP, 'dl_type'),
lastextra = True
)
ip4_packet_l7 = nstruct((ip4_payload,),
base = ethernet_l7,
classifyby = (ETHERTYPE_IP,),
name = 'ip4_packet_l7',
init = packvalue(ETHERTYPE_IP, 'dl_type'),
lastextra = True
)
def create_fragments_ip4(payload, mtu = 1500, options = '', fragment_options = '', proto = IPPROTO_UDP, *args, **kwargs):
if hasattr(payload, '_tobytes'):
payload = payload._tobytes()
if len(payload) > 65536:
raise ValueError('Payload is too large')
ip4_header_size = len(ip4_header(options = options))
ip4_header_frag_size = len(ip4_header(options = fragment_options))
if len(payload) + ip4_header_size <= mtu:
# No fragmentation
return [ip4_payload_fragment(payload = payload,
options = options,
frag_off = 0,
proto = proto,
*args,
**kwargs)]
else:
if mtu < ip4_header_size + 8 or mtu < ip4_header_frag_size + 8:
raise ValueError('MTU is too small, at least %d is required, got %d' %
(max(ip4_header_size + 8, ip4_header_frag_size + 8), mtu))
frags = []
next_len = (mtu - ip4_header_size) // 8
offset = 0
totalsize = len(payload)
frags.append(ip4_payload_fragment(payload = payload[offset * 8: (offset + next_len) * 8],
options = options,
frag_off = IP_MF,
proto = proto,
*args,
**kwargs))
while True:
offset += next_len
if totalsize - offset * 8 + ip4_header_frag_size <= mtu:
frags.append(ip4_payload_fragment(payload = payload[offset * 8:],
options = fragment_options,
frag_off = offset,
proto = proto,
*args,
**kwargs))
break
else:
next_len = (mtu - ip4_header_frag_size) // 8
frags.append(ip4_payload_fragment(payload = payload[offset * 8: (offset + next_len) * 8],
options = fragment_options,
frag_off = IP_MF | offset,
proto = proto,
*args,
**kwargs))
return frags
def create_fragments_ip4_packet(payload, mtu = 1500, options = '', fragment_options = '', proto = IPPROTO_UDP, **kwargs):
if hasattr(payload, '_tobytes'):
payload = payload._tobytes()
if len(payload) > 65536:
raise ValueError('Payload is too large')
ip4_header_size = len(ip4_header(options = options))
ip4_header_frag_size = len(ip4_header(options = fragment_options))
if len(payload) + ip4_header_size <= mtu:
# No fragmentation
return [create_packet(ip4_packet, payload = payload,
options = options,
frag_off = 0,
total_len = len(payload) + ip4_header_size,
proto = proto,
**kwargs)]
else:
if mtu < ip4_header_size + 8 or mtu < ip4_header_frag_size + 8:
raise ValueError('MTU is too small, at least %d is required, got %d' %
(max(ip4_header_size + 8, ip4_header_frag_size + 8), mtu))
frags = []
next_len = (mtu - ip4_header_size) // 8
offset = 0
totalsize = len(payload)
frags.append(create_packet(ip4_packet, payload = payload[offset * 8: (offset + next_len) * 8],
options = options,
frag_off = IP_MF,
total_len = next_len * 8 + ip4_header_size,
proto = proto,
**kwargs))
while True:
offset += next_len