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## This file is part of Scapy
## See for more informations
## Copyright (C) Philippe Biondi <>
## This program is published under a GPLv2 license
## Copyright (C) 2005 Guillaume Valadon <>
## Arnaud Ebalard <>
Utility functions for IPv6.
from __future__ import absolute_import
import random
import socket
import struct
from scapy.config import conf
import scapy.consts
from import *
from scapy.utils import *
from scapy.compat import *
from scapy.pton_ntop import *
from scapy.volatile import RandMAC
from scapy.error import warning
from functools import reduce
from scapy.modules.six.moves import range
def construct_source_candidate_set(addr, plen, laddr):
Given all addresses assigned to a specific interface ('laddr' parameter),
this function returns the "candidate set" associated with 'addr/plen'.
Basically, the function filters all interface addresses to keep only those
that have the same scope as provided prefix.
This is on this list of addresses that the source selection mechanism
will then be performed to select the best source address associated
with some specific destination that uses this prefix.
def cset_sort(x,y):
x_global = 0
if in6_isgladdr(x):
x_global = 1
y_global = 0
if in6_isgladdr(y):
y_global = 1
res = y_global - x_global
if res != 0 or y_global != 1:
return res
# two global addresses: if one is native, it wins.
if not in6_isaddr6to4(x):
return -1;
return -res
cset = []
if in6_isgladdr(addr) or in6_isuladdr(addr):
cset = (x for x in laddr if x[1] == IPV6_ADDR_GLOBAL)
elif in6_islladdr(addr):
cset = (x for x in laddr if x[1] == IPV6_ADDR_LINKLOCAL)
elif in6_issladdr(addr):
cset = (x for x in laddr if x[1] == IPV6_ADDR_SITELOCAL)
elif in6_ismaddr(addr):
if in6_ismnladdr(addr):
cset = [('::1', 16, scapy.consts.LOOPBACK_INTERFACE)]
elif in6_ismgladdr(addr):
cset = (x for x in laddr if x[1] == IPV6_ADDR_GLOBAL)
elif in6_ismlladdr(addr):
cset = (x for x in laddr if x[1] == IPV6_ADDR_LINKLOCAL)
elif in6_ismsladdr(addr):
cset = (x for x in laddr if x[1] == IPV6_ADDR_SITELOCAL)
elif addr == '::' and plen == 0:
cset = (x for x in laddr if x[1] == IPV6_ADDR_GLOBAL)
cset = [x[0] for x in cset]
# TODO convert the cmd use into a key
cset.sort(key=cmp_to_key(cset_sort)) # Sort with global addresses first
return cset
def get_source_addr_from_candidate_set(dst, candidate_set):
This function implement a limited version of source address selection
algorithm defined in section 5 of RFC 3484. The format is very different
from that described in the document because it operates on a set
of candidate source address for some specific route.
def scope_cmp(a, b):
Given two addresses, returns -1, 0 or 1 based on comparison of
their scope
scope_mapper = {IPV6_ADDR_GLOBAL: 4,
sa = in6_getscope(a)
if sa == -1:
sb = in6_getscope(b)
if sb == -1:
sa = scope_mapper[sa]
sb = scope_mapper[sb]
if sa == sb:
return 0
if sa > sb:
return 1
return -1
def rfc3484_cmp(source_a, source_b):
The function implements a limited version of the rules from Source
Address selection algorithm defined section of RFC 3484.
# Rule 1: Prefer same address
if source_a == dst:
return 1
if source_b == dst:
return 1
# Rule 2: Prefer appropriate scope
tmp = scope_cmp(source_a, source_b)
if tmp == -1:
if scope_cmp(source_a, dst) == -1:
return 1
return -1
elif tmp == 1:
if scope_cmp(source_b, dst) == -1:
return 1
return -1
# Rule 3: cannot be easily implemented
# Rule 4: cannot be easily implemented
# Rule 5: does not make sense here
# Rule 6: cannot be implemented
# Rule 7: cannot be implemented
# Rule 8: Longest prefix match
tmp1 = in6_get_common_plen(source_a, dst)
tmp2 = in6_get_common_plen(source_b, dst)
if tmp1 > tmp2:
return 1
elif tmp2 > tmp1:
return -1
return 0
if not candidate_set:
# Should not happen
return None
candidate_set.sort(key=cmp_to_key(rfc3484_cmp), reverse=True)
return candidate_set[0]
# Think before modify it : for instance, FE::1 does exist and is unicast
# there are many others like that.
# TODO : integrate Unique Local Addresses
def in6_getAddrType(addr):
naddr = inet_pton(socket.AF_INET6, addr)
paddr = inet_ntop(socket.AF_INET6, naddr) # normalize
addrType = 0
# _Assignable_ Global Unicast Address space
# is defined in RFC 3513 as those in 2000::/3
if ((orb(naddr[0]) & 0xE0) == 0x20):
if naddr[:2] == b' \x02': # Mark 6to4 @
addrType |= IPV6_ADDR_6TO4
elif orb(naddr[0]) == 0xff: # multicast
addrScope = paddr[3]
if addrScope == '2':
elif addrScope == 'e':
elif ((orb(naddr[0]) == 0xfe) and ((int(paddr[2], 16) & 0xC) == 0x8)):
elif paddr == "::1":
elif paddr == "::":
# Everything else is global unicast (RFC 3513)
# Even old deprecated (RFC3879) Site-Local addresses
return addrType
def in6_mactoifaceid(mac, ulbit=None):
Compute the interface ID in modified EUI-64 format associated
to the Ethernet address provided as input.
value taken by U/L bit in the interface identifier is basically
the reversed value of that in given MAC address it can be forced
to a specific value by using optional 'ulbit' parameter.
if len(mac) != 17: return None
m = "".join(mac.split(':'))
if len(m) != 12: return None
first = int(m[0:2], 16)
if ulbit is None or not (ulbit == 0 or ulbit == 1):
ulbit = [1,'-',0][first & 0x02]
ulbit *= 2
first = "%.02x" % ((first & 0xFD) | ulbit)
eui64 = first + m[2:4] + ":" + m[4:6] + "FF:FE" + m[6:8] + ":" + m[8:12]
return eui64.upper()
def in6_ifaceidtomac(ifaceid): # TODO: finish commenting function behavior
Extract the mac address from provided iface ID. Iface ID is provided
in printable format ("XXXX:XXFF:FEXX:XXXX", eventually compressed). None
is returned on error.
ifaceid = inet_pton(socket.AF_INET6, "::"+ifaceid)[8:16]
return None
if ifaceid[3:5] != b'\xff\xfe':
return None
first = struct.unpack("B", ifaceid[:1])[0]
ulbit = 2*[1,'-',0][first & 0x02]
first = struct.pack("B", ((first & 0xFD) | ulbit))
oui = first + ifaceid[1:3]
end = ifaceid[5:]
l = ["%.02x" % orb(x) for x in list(oui + end)]
return ":".join(l)
def in6_addrtomac(addr):
Extract the mac address from provided address. None is returned
on error.
mask = inet_pton(socket.AF_INET6, "::ffff:ffff:ffff:ffff")
x = in6_and(mask, inet_pton(socket.AF_INET6, addr))
ifaceid = inet_ntop(socket.AF_INET6, x)[2:]
return in6_ifaceidtomac(ifaceid)
def in6_addrtovendor(addr):
Extract the MAC address from a modified EUI-64 constructed IPv6
address provided and use the IANA oui.txt file to get the vendor.
The database used for the conversion is the one loaded by Scapy,
based on Wireshark (/usr/share/wireshark/wireshark/manuf) None
is returned on error, "UNKNOWN" if the vendor is unknown.
mac = in6_addrtomac(addr)
if mac is None:
return None
res = conf.manufdb._get_manuf(mac)
if len(res) == 17 and res.count(':') != 5: # Mac address, i.e. unknown
res = "UNKNOWN"
return res
def in6_getLinkScopedMcastAddr(addr, grpid=None, scope=2):
Generate a Link-Scoped Multicast Address as described in RFC 4489.
Returned value is in printable notation.
'addr' parameter specifies the link-local address to use for generating
Link-scoped multicast address IID.
By default, the function returns a ::/96 prefix (aka last 32 bits of
returned address are null). If a group id is provided through 'grpid'
parameter, last 32 bits of the address are set to that value (accepted
formats : b'\x12\x34\x56\x78' or '12345678' or 0x12345678 or 305419896).
By default, generated address scope is Link-Local (2). That value can
be modified by passing a specific 'scope' value as an argument of the
function. RFC 4489 only authorizes scope values <= 2. Enforcement
is performed by the function (None will be returned).
If no link-local address can be used to generate the Link-Scoped IPv6
Multicast address, or if another error occurs, None is returned.
if not scope in [0, 1, 2]:
return None
if not in6_islladdr(addr):
return None
addr = inet_pton(socket.AF_INET6, addr)
warning("in6_getLinkScopedMcastPrefix(): Invalid address provided")
return None
iid = addr[8:]
if grpid is None:
grpid = b'\x00\x00\x00\x00'
if isinstance(grpid, (bytes, str)):
if len(grpid) == 8:
grpid = int(grpid, 16) & 0xffffffff
warning("in6_getLinkScopedMcastPrefix(): Invalid group id provided")
return None
elif len(grpid) == 4:
grpid = struct.unpack("!I", grpid)[0]
warning("in6_getLinkScopedMcastPrefix(): Invalid group id provided")
return None
grpid = struct.pack("!I", grpid)
flgscope = struct.pack("B", 0xff & ((0x3 << 4) | scope))
plen = b'\xff'
res = b'\x00'
a = b'\xff' + flgscope + res + plen + iid + grpid
return inet_ntop(socket.AF_INET6, a)
def in6_get6to4Prefix(addr):
Returns the /48 6to4 prefix associated with provided IPv4 address
On error, None is returned. No check is performed on public/private
status of the address
addr = inet_pton(socket.AF_INET, addr)
addr = inet_ntop(socket.AF_INET6, b'\x20\x02'+addr+b'\x00'*10)
return None
return addr
def in6_6to4ExtractAddr(addr):
Extract IPv4 address embedded in 6to4 address. Passed address must be
a 6to4 address. None is returned on error.
addr = inet_pton(socket.AF_INET6, addr)
return None
if addr[:2] != b" \x02":
return None
return inet_ntop(socket.AF_INET, addr[2:6])
def in6_getLocalUniquePrefix():
Returns a pseudo-randomly generated Local Unique prefix. Function
follows recommendation of Section 3.2.2 of RFC 4193 for prefix
# Extracted from RFC 1305 (NTP) :
# NTP timestamps are represented as a 64-bit unsigned fixed-point number,
# in seconds relative to 0h on 1 January 1900. The integer part is in the
# first 32 bits and the fraction part in the last 32 bits.
# epoch = (1900, 1, 1, 0, 0, 0, 5, 1, 0)
# x = time.time()
# from time import gmtime, strftime, gmtime, mktime
# delta = mktime(gmtime(0)) - mktime(self.epoch)
# x = x-delta
tod = time.time() # time of day. Will bother with epoch later
i = int(tod)
j = int((tod - i)*(2**32))
tod = struct.pack("!II", i,j)
mac = RandMAC()
# construct modified EUI-64 ID
eui64 = inet_pton(socket.AF_INET6, '::' + in6_mactoifaceid(mac))[8:]
import hashlib
globalid = hashlib.sha1(tod+eui64).digest()[:5]
return inet_ntop(socket.AF_INET6, b'\xfd' + globalid + b'\x00'*10)
def in6_getRandomizedIfaceId(ifaceid, previous=None):
Implements the interface ID generation algorithm described in RFC 3041.
The function takes the Modified EUI-64 interface identifier generated
as described in RFC 4291 and an optional previous history value (the
first element of the output of this function). If no previous interface
identifier is provided, a random one is generated. The function returns
a tuple containing the randomized interface identifier and the history
value (for possible future use). Input and output values are provided in
a "printable" format as depicted below.
>>> in6_getRandomizedIfaceId('20b:93ff:feeb:2d3')
('4c61:76ff:f46a:a5f3', 'd006:d540:db11:b092')
>>> in6_getRandomizedIfaceId('20b:93ff:feeb:2d3',
('fe97:46fe:9871:bd38', 'eeed:d79c:2e3f:62e')
s = b""
if previous is None:
d = b"".join(chb(x) for x in range(256))
for _ in range(8):
s += chb(random.choice(d))
previous = s
s = inet_pton(socket.AF_INET6, "::"+ifaceid)[8:] + previous
import hashlib
s = hashlib.md5(s).digest()
s1,s2 = s[:8],s[8:]
s1 = chb(orb(s1[0]) | 0x04) + s1[1:]
s1 = inet_ntop(socket.AF_INET6, b"\xff"*8 + s1)[20:]
s2 = inet_ntop(socket.AF_INET6, b"\xff"*8 + s2)[20:]
return (s1, s2)
_rfc1924map = [ '0','1','2','3','4','5','6','7','8','9','A','B','C','D','E',
'>','?','@','^','_','`','{','|','}','~' ]
def in6_ctop(addr):
Convert an IPv6 address in Compact Representation Notation
(RFC 1924) to printable representation ;-)
Returns None on error.
if len(addr) != 20 or not reduce(lambda x,y: x and y,
[x in _rfc1924map for x in addr]):
return None
i = 0
for c in addr:
j = _rfc1924map.index(c)
i = 85*i + j
res = []
for j in range(4):
res.append(struct.pack("!I", i%2**32))
i = i//(2**32)
return inet_ntop(socket.AF_INET6, b"".join(res))
def in6_ptoc(addr):
Converts an IPv6 address in printable representation to RFC
1924 Compact Representation ;-)
Returns None on error.
d=struct.unpack("!IIII", inet_pton(socket.AF_INET6, addr))
return None
res = 0
m = [2**96, 2**64, 2**32, 1]
for i in range(4):
res += d[i]*m[i]
rem = res
res = []
while rem:
rem = rem//85
return "".join(res)
def in6_isaddr6to4(x):
Return True if provided address (in printable format) is a 6to4
address (being in 2002::/16).
x = inet_pton(socket.AF_INET6, x)
return x[:2] == b' \x02'
conf.teredoPrefix = "2001::" # old one was 3ffe:831f (it is a /32)
conf.teredoServerPort = 3544
def in6_isaddrTeredo(x):
Return True if provided address is a Teredo, meaning it is under
the /32 conf.teredoPrefix prefix value (by default, 2001::).
Otherwise, False is returned. Address must be passed in printable
our = inet_pton(socket.AF_INET6, x)[0:4]
teredoPrefix = inet_pton(socket.AF_INET6, conf.teredoPrefix)[0:4]
return teredoPrefix == our
def teredoAddrExtractInfo(x):
Extract information from a Teredo address. Return value is
a 4-tuple made of IPv4 address of Teredo server, flag value (int),
mapped address (non obfuscated) and mapped port (non obfuscated).
No specific checks are performed on passed address.
addr = inet_pton(socket.AF_INET6, x)
server = inet_ntop(socket.AF_INET, addr[4:8])
flag = struct.unpack("!H",addr[8:10])[0]
mappedport = struct.unpack("!H",strxor(addr[10:12],b'\xff'*2))[0]
mappedaddr = inet_ntop(socket.AF_INET, strxor(addr[12:16],b'\xff'*4))
return server, flag, mappedaddr, mappedport
def in6_iseui64(x):
Return True if provided address has an interface identifier part
created in modified EUI-64 format (meaning it matches *::*:*ff:fe*:*).
Otherwise, False is returned. Address must be passed in printable
eui64 = inet_pton(socket.AF_INET6, '::ff:fe00:0')
x = in6_and(inet_pton(socket.AF_INET6, x), eui64)
return x == eui64
def in6_isanycast(x): # RFC 2526
if in6_iseui64(x):
s = '::fdff:ffff:ffff:ff80'
packed_x = inet_pton(socket.AF_INET6, x)
packed_s = inet_pton(socket.AF_INET6, s)
x_and_s = in6_and(packed_x, packed_s)
return x_and_s == packed_s
# not EUI-64
#| n bits | 121-n bits | 7 bits |
#| subnet prefix | 1111111...111111 | anycast ID |
# | interface identifier field |
warning('in6_isanycast(): TODO not EUI-64')
return 0
def _in6_bitops(a1, a2, operator=0):
a1 = struct.unpack('4I', a1)
a2 = struct.unpack('4I', a2)
fop = [ lambda x,y: x | y,
lambda x,y: x & y,
lambda x,y: x ^ y
ret = map(fop[operator%len(fop)], a1, a2)
return b"".join(struct.pack('I', x) for x in ret)
def in6_or(a1, a2):
Provides a bit to bit OR of provided addresses. They must be
passed in network format. Return value is also an IPv6 address
in network format.
return _in6_bitops(a1, a2, 0)
def in6_and(a1, a2):
Provides a bit to bit AND of provided addresses. They must be
passed in network format. Return value is also an IPv6 address
in network format.
return _in6_bitops(a1, a2, 1)
def in6_xor(a1, a2):
Provides a bit to bit XOR of provided addresses. They must be
passed in network format. Return value is also an IPv6 address
in network format.
return _in6_bitops(a1, a2, 2)
def in6_cidr2mask(m):
Return the mask (bitstring) associated with provided length
value. For instance if function is called on 48, return value is
if m > 128 or m < 0:
raise Scapy_Exception("value provided to in6_cidr2mask outside [0, 128] domain (%d)" % m)
t = []
for i in range(0, 4):
t.append(max(0, 2**32 - 2**(32-min(32, m))))
m -= 32
return b"".join(struct.pack('!I', x) for x in t)
def in6_getnsma(a):
Return link-local solicited-node multicast address for given
address. Passed address must be provided in network format.
Returned value is also in network format.
r = in6_and(a, inet_pton(socket.AF_INET6, '::ff:ffff'))
r = in6_or(inet_pton(socket.AF_INET6, 'ff02::1:ff00:0'), r)
return r
def in6_getnsmac(a): # return multicast Ethernet address associated with multicast v6 destination
Return the multicast mac address associated with provided
IPv6 address. Passed address must be in network format.
a = struct.unpack('16B', a)[-4:]
mac = '33:33:'
mac += ':'.join("%.2x" %x for x in a)
return mac
def in6_getha(prefix):
Return the anycast address associated with all home agents on a given
r = in6_and(inet_pton(socket.AF_INET6, prefix), in6_cidr2mask(64))
r = in6_or(r, inet_pton(socket.AF_INET6, '::fdff:ffff:ffff:fffe'))
return inet_ntop(socket.AF_INET6, r)
def in6_ptop(str):
Normalizes IPv6 addresses provided in printable format, returning the
same address in printable format. (2001:0db8:0:0::1 -> 2001:db8::1)
return inet_ntop(socket.AF_INET6, inet_pton(socket.AF_INET6, str))
def in6_isincluded(addr, prefix, plen):
Returns True when 'addr' belongs to prefix/plen. False otherwise.
temp = inet_pton(socket.AF_INET6, addr)
pref = in6_cidr2mask(plen)
zero = inet_pton(socket.AF_INET6, prefix)
return zero == in6_and(temp, pref)
def in6_isllsnmaddr(str):
Return True if provided address is a link-local solicited node
multicast address, i.e. belongs to ff02::1:ff00:0/104. False is
returned otherwise.
temp = in6_and(b"\xff"*13+b"\x00"*3, inet_pton(socket.AF_INET6, str))
temp2 = b'\xff\x02\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\xff\x00\x00\x00'
return temp == temp2
def in6_isdocaddr(str):
Returns True if provided address in printable format belongs to
2001:db8::/32 address space reserved for documentation (as defined
in RFC 3849).
return in6_isincluded(str, '2001:db8::', 32)
def in6_islladdr(str):
Returns True if provided address in printable format belongs to
_allocated_ link-local unicast address space (fe80::/10)
return in6_isincluded(str, 'fe80::', 10)
def in6_issladdr(str):
Returns True if provided address in printable format belongs to
_allocated_ site-local address space (fec0::/10). This prefix has
been deprecated, address being now reserved by IANA. Function
will remain for historic reasons.
return in6_isincluded(str, 'fec0::', 10)
def in6_isuladdr(str):
Returns True if provided address in printable format belongs to
Unique local address space (fc00::/7).
return in6_isincluded(str, 'fc00::', 7)
# TODO : we should see the status of Unique Local addresses against
# global address space.
# Up-to-date information is available through RFC 3587.
# We should review function behavior based on its content.
def in6_isgladdr(str):
Returns True if provided address in printable format belongs to
_allocated_ global address space (2000::/3). Please note that,
Unique Local addresses (FC00::/7) are not part of global address
space, and won't match.
return in6_isincluded(str, '2000::', 3)
def in6_ismaddr(str):
Returns True if provided address in printable format belongs to
allocated Multicast address space (ff00::/8).
return in6_isincluded(str, 'ff00::', 8)
def in6_ismnladdr(str):
Returns True if address belongs to node-local multicast address
space (ff01::/16) as defined in RFC
return in6_isincluded(str, 'ff01::', 16)
def in6_ismgladdr(str):
Returns True if address belongs to global multicast address
space (ff0e::/16).
return in6_isincluded(str, 'ff0e::', 16)
def in6_ismlladdr(str):
Returns True if address belongs to link-local multicast address
space (ff02::/16)
return in6_isincluded(str, 'ff02::', 16)
def in6_ismsladdr(str):
Returns True if address belongs to site-local multicast address
space (ff05::/16). Site local address space has been deprecated.
Function remains for historic reasons.
return in6_isincluded(str, 'ff05::', 16)
def in6_isaddrllallnodes(str):
Returns True if address is the link-local all-nodes multicast
address (ff02::1).
return (inet_pton(socket.AF_INET6, "ff02::1") ==
inet_pton(socket.AF_INET6, str))
def in6_isaddrllallservers(str):
Returns True if address is the link-local all-servers multicast
address (ff02::2).
return (inet_pton(socket.AF_INET6, "ff02::2") ==
inet_pton(socket.AF_INET6, str))
def in6_getscope(addr):
Returns the scope of the address.
if in6_isgladdr(addr) or in6_isuladdr(addr):
elif in6_islladdr(addr):
elif in6_issladdr(addr):
elif in6_ismaddr(addr):
if in6_ismgladdr(addr):
elif in6_ismlladdr(addr):
elif in6_ismsladdr(addr):
elif in6_ismnladdr(addr):
scope = -1
elif addr == '::1':
scope = -1
return scope
def in6_get_common_plen(a, b):
Return common prefix length of IPv6 addresses a and b.
def matching_bits(byte1, byte2):
for i in range(8):
cur_mask = 0x80 >> i
if (byte1 & cur_mask) != (byte2 & cur_mask):
return i
return 8
tmpA = inet_pton(socket.AF_INET6, a)
tmpB = inet_pton(socket.AF_INET6, b)
for i in range(16):
mbits = matching_bits(orb(tmpA[i]), orb(tmpB[i]))
if mbits != 8:
return 8*i + mbits
return 128
def in6_isvalid(address):
"""Return True if 'address' is a valid IPv6 address string, False
socket.inet_pton(socket.AF_INET6, address)
return True
return False