609 lines
20 KiB
Python
609 lines
20 KiB
Python
# Copyright (C) 2012 Nippon Telegraph and Telephone Corporation.
|
|
#
|
|
# Licensed under the Apache License, Version 2.0 (the "License");
|
|
# you may not use this file except in compliance with the License.
|
|
# You may obtain a copy of the License at
|
|
#
|
|
# http://www.apache.org/licenses/LICENSE-2.0
|
|
#
|
|
# Unless required by applicable law or agreed to in writing, software
|
|
# distributed under the License is distributed on an "AS IS" BASIS,
|
|
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
|
|
# implied.
|
|
# See the License for the specific language governing permissions and
|
|
# limitations under the License.
|
|
|
|
import abc
|
|
import six
|
|
import struct
|
|
from . import packet_base
|
|
from . import icmpv6
|
|
from . import tcp
|
|
from . import udp
|
|
from . import sctp
|
|
from . import gre
|
|
from . import in_proto as inet
|
|
from ryu.lib import addrconv
|
|
from ryu.lib import stringify
|
|
|
|
|
|
IPV6_ADDRESS_PACK_STR = '!16s'
|
|
IPV6_ADDRESS_LEN = struct.calcsize(IPV6_ADDRESS_PACK_STR)
|
|
IPV6_PSEUDO_HEADER_PACK_STR = '!16s16s3xB'
|
|
|
|
|
|
class ipv6(packet_base.PacketBase):
|
|
"""IPv6 (RFC 2460) header encoder/decoder class.
|
|
|
|
An instance has the following attributes at least.
|
|
Most of them are same to the on-wire counterparts but in host byte order.
|
|
IPv6 addresses are represented as a string like 'ff02::1'.
|
|
__init__ takes the corresponding args in this order.
|
|
|
|
.. tabularcolumns:: |l|p{30em}|l|
|
|
|
|
============== ======================================== ==================
|
|
Attribute Description Example
|
|
============== ======================================== ==================
|
|
version Version
|
|
traffic_class Traffic Class
|
|
flow_label When decoding, Flow Label.
|
|
When encoding, the most significant 8
|
|
bits of Flow Label.
|
|
payload_length Payload Length
|
|
nxt Next Header
|
|
hop_limit Hop Limit
|
|
src Source Address 'ff02::1'
|
|
dst Destination Address '::'
|
|
ext_hdrs Extension Headers
|
|
============== ======================================== ==================
|
|
"""
|
|
|
|
_PACK_STR = '!IHBB16s16s'
|
|
_MIN_LEN = struct.calcsize(_PACK_STR)
|
|
_IPV6_EXT_HEADER_TYPE = {}
|
|
_TYPE = {
|
|
'ascii': [
|
|
'src', 'dst'
|
|
]
|
|
}
|
|
|
|
@staticmethod
|
|
def register_header_type(type_):
|
|
def _register_header_type(cls):
|
|
ipv6._IPV6_EXT_HEADER_TYPE[type_] = cls
|
|
return cls
|
|
return _register_header_type
|
|
|
|
def __init__(self, version=6, traffic_class=0, flow_label=0,
|
|
payload_length=0, nxt=inet.IPPROTO_TCP, hop_limit=255,
|
|
src='10::10', dst='20::20', ext_hdrs=None):
|
|
super(ipv6, self).__init__()
|
|
self.version = version
|
|
self.traffic_class = traffic_class
|
|
self.flow_label = flow_label
|
|
self.payload_length = payload_length
|
|
self.nxt = nxt
|
|
self.hop_limit = hop_limit
|
|
self.src = src
|
|
self.dst = dst
|
|
ext_hdrs = ext_hdrs or []
|
|
assert isinstance(ext_hdrs, list)
|
|
for ext_hdr in ext_hdrs:
|
|
assert isinstance(ext_hdr, header)
|
|
self.ext_hdrs = ext_hdrs
|
|
|
|
@classmethod
|
|
def parser(cls, buf):
|
|
(v_tc_flow, payload_length, nxt, hlim, src, dst) = struct.unpack_from(
|
|
cls._PACK_STR, buf)
|
|
version = v_tc_flow >> 28
|
|
traffic_class = (v_tc_flow >> 20) & 0xff
|
|
flow_label = v_tc_flow & 0xfffff
|
|
hop_limit = hlim
|
|
offset = cls._MIN_LEN
|
|
last = nxt
|
|
ext_hdrs = []
|
|
while True:
|
|
cls_ = cls._IPV6_EXT_HEADER_TYPE.get(last)
|
|
if not cls_:
|
|
break
|
|
hdr = cls_.parser(buf[offset:])
|
|
ext_hdrs.append(hdr)
|
|
offset += len(hdr)
|
|
last = hdr.nxt
|
|
msg = cls(version, traffic_class, flow_label, payload_length,
|
|
nxt, hop_limit, addrconv.ipv6.bin_to_text(src),
|
|
addrconv.ipv6.bin_to_text(dst), ext_hdrs)
|
|
return (msg, ipv6.get_packet_type(last),
|
|
buf[offset:offset + payload_length])
|
|
|
|
def serialize(self, payload, prev):
|
|
hdr = bytearray(40)
|
|
v_tc_flow = (self.version << 28 | self.traffic_class << 20 |
|
|
self.flow_label)
|
|
struct.pack_into(ipv6._PACK_STR, hdr, 0, v_tc_flow,
|
|
self.payload_length, self.nxt, self.hop_limit,
|
|
addrconv.ipv6.text_to_bin(self.src),
|
|
addrconv.ipv6.text_to_bin(self.dst))
|
|
if self.ext_hdrs:
|
|
for ext_hdr in self.ext_hdrs:
|
|
hdr.extend(ext_hdr.serialize())
|
|
if 0 == self.payload_length:
|
|
payload_length = len(payload)
|
|
for ext_hdr in self.ext_hdrs:
|
|
payload_length += len(ext_hdr)
|
|
self.payload_length = payload_length
|
|
struct.pack_into('!H', hdr, 4, self.payload_length)
|
|
return hdr
|
|
|
|
def __len__(self):
|
|
ext_hdrs_len = 0
|
|
for ext_hdr in self.ext_hdrs:
|
|
ext_hdrs_len += len(ext_hdr)
|
|
return self._MIN_LEN + ext_hdrs_len
|
|
|
|
|
|
ipv6.register_packet_type(icmpv6.icmpv6, inet.IPPROTO_ICMPV6)
|
|
ipv6.register_packet_type(tcp.tcp, inet.IPPROTO_TCP)
|
|
ipv6.register_packet_type(udp.udp, inet.IPPROTO_UDP)
|
|
ipv6.register_packet_type(sctp.sctp, inet.IPPROTO_SCTP)
|
|
ipv6.register_packet_type(gre.gre, inet.IPPROTO_GRE)
|
|
|
|
|
|
@six.add_metaclass(abc.ABCMeta)
|
|
class header(stringify.StringifyMixin):
|
|
"""extension header abstract class."""
|
|
|
|
def __init__(self, nxt):
|
|
self.nxt = nxt
|
|
|
|
@classmethod
|
|
@abc.abstractmethod
|
|
def parser(cls, buf):
|
|
pass
|
|
|
|
@abc.abstractmethod
|
|
def serialize(self):
|
|
pass
|
|
|
|
@abc.abstractmethod
|
|
def __len__(self):
|
|
pass
|
|
|
|
|
|
class opt_header(header):
|
|
"""an abstract class for Hop-by-Hop Options header and destination
|
|
header."""
|
|
|
|
_PACK_STR = '!BB'
|
|
_MIN_LEN = struct.calcsize(_PACK_STR)
|
|
_FIX_SIZE = 8
|
|
_class_prefixes = ['option']
|
|
|
|
@abc.abstractmethod
|
|
def __init__(self, nxt, size, data):
|
|
super(opt_header, self).__init__(nxt)
|
|
assert not (size % 8)
|
|
self.size = size
|
|
self.data = data
|
|
|
|
@classmethod
|
|
def parser(cls, buf):
|
|
(nxt, len_) = struct.unpack_from(cls._PACK_STR, buf)
|
|
data_len = cls._FIX_SIZE + int(len_)
|
|
data = []
|
|
size = cls._MIN_LEN
|
|
while size < data_len:
|
|
(type_, ) = struct.unpack_from('!B', buf[size:])
|
|
if type_ == 0:
|
|
opt = option(type_, -1, None)
|
|
size += 1
|
|
else:
|
|
opt = option.parser(buf[size:])
|
|
size += len(opt)
|
|
data.append(opt)
|
|
return cls(nxt, len_, data)
|
|
|
|
def serialize(self):
|
|
buf = struct.pack(self._PACK_STR, self.nxt, self.size)
|
|
buf = bytearray(buf)
|
|
if self.data is None:
|
|
self.data = [option(type_=1, len_=4,
|
|
data=b'\x00\x00\x00\x00')]
|
|
for opt in self.data:
|
|
buf.extend(opt.serialize())
|
|
return buf
|
|
|
|
def __len__(self):
|
|
return self._FIX_SIZE + self.size
|
|
|
|
|
|
@ipv6.register_header_type(inet.IPPROTO_HOPOPTS)
|
|
class hop_opts(opt_header):
|
|
"""IPv6 (RFC 2460) Hop-by-Hop Options header encoder/decoder class.
|
|
|
|
This is used with ryu.lib.packet.ipv6.ipv6.
|
|
|
|
An instance has the following attributes at least.
|
|
Most of them are same to the on-wire counterparts but in host byte order.
|
|
__init__ takes the corresponding args in this order.
|
|
|
|
.. tabularcolumns:: |l|L|
|
|
|
|
============== =======================================
|
|
Attribute Description
|
|
============== =======================================
|
|
nxt Next Header
|
|
size the length of the Hop-by-Hop Options header,
|
|
not include the first 8 octet.
|
|
data IPv6 options.
|
|
============== =======================================
|
|
"""
|
|
TYPE = inet.IPPROTO_HOPOPTS
|
|
|
|
def __init__(self, nxt=inet.IPPROTO_TCP, size=0, data=None):
|
|
super(hop_opts, self).__init__(nxt, size, data)
|
|
|
|
|
|
@ipv6.register_header_type(inet.IPPROTO_DSTOPTS)
|
|
class dst_opts(opt_header):
|
|
"""IPv6 (RFC 2460) destination header encoder/decoder class.
|
|
|
|
This is used with ryu.lib.packet.ipv6.ipv6.
|
|
|
|
An instance has the following attributes at least.
|
|
Most of them are same to the on-wire counterparts but in host byte order.
|
|
__init__ takes the corresponding args in this order.
|
|
|
|
.. tabularcolumns:: |l|L|
|
|
|
|
============== =======================================
|
|
Attribute Description
|
|
============== =======================================
|
|
nxt Next Header
|
|
size the length of the destination header,
|
|
not include the first 8 octet.
|
|
data IPv6 options.
|
|
============== =======================================
|
|
"""
|
|
TYPE = inet.IPPROTO_DSTOPTS
|
|
|
|
def __init__(self, nxt=inet.IPPROTO_TCP, size=0, data=None):
|
|
super(dst_opts, self).__init__(nxt, size, data)
|
|
|
|
|
|
class option(stringify.StringifyMixin):
|
|
r"""IPv6 (RFC 2460) Options header encoder/decoder class.
|
|
|
|
This is used with ryu.lib.packet.ipv6.hop_opts or
|
|
ryu.lib.packet.ipv6.dst_opts.
|
|
|
|
An instance has the following attributes at least.
|
|
Most of them are same to the on-wire counterparts but in host byte order.
|
|
__init__ takes the corresponding args in this order.
|
|
|
|
.. tabularcolumns:: |l|L|
|
|
|
|
============== =======================================
|
|
Attribute Description
|
|
============== =======================================
|
|
type\_ option type.
|
|
len\_ the length of data. -1 if type\_ is 0.
|
|
data an option value. None if len\_ is 0 or -1.
|
|
============== =======================================
|
|
"""
|
|
|
|
_PACK_STR = '!BB'
|
|
_MIN_LEN = struct.calcsize(_PACK_STR)
|
|
|
|
def __init__(self, type_=0, len_=-1, data=None):
|
|
self.type_ = type_
|
|
self.len_ = len_
|
|
self.data = data
|
|
|
|
@classmethod
|
|
def parser(cls, buf):
|
|
(type_, ) = struct.unpack_from('!B', buf)
|
|
if not type_:
|
|
cls_ = cls(type_, -1, None)
|
|
else:
|
|
data = None
|
|
(type_, len_) = struct.unpack_from(cls._PACK_STR, buf)
|
|
if len_:
|
|
form = "%ds" % len_
|
|
(data, ) = struct.unpack_from(form, buf, cls._MIN_LEN)
|
|
cls_ = cls(type_, len_, data)
|
|
return cls_
|
|
|
|
def serialize(self):
|
|
data = None
|
|
if not self.type_:
|
|
data = struct.pack('!B', self.type_)
|
|
elif not self.len_:
|
|
data = struct.pack(self._PACK_STR, self.type_, self.len_)
|
|
else:
|
|
form = "%ds" % self.len_
|
|
data = struct.pack(self._PACK_STR + form, self.type_,
|
|
self.len_, self.data)
|
|
return data
|
|
|
|
def __len__(self):
|
|
return self._MIN_LEN + self.len_
|
|
|
|
|
|
@ipv6.register_header_type(inet.IPPROTO_ROUTING)
|
|
class routing(header):
|
|
"""An IPv6 Routing Header decoder class.
|
|
This class has only the parser method.
|
|
|
|
IPv6 Routing Header types.
|
|
|
|
http://www.iana.org/assignments/ipv6-parameters/ipv6-parameters.xhtml
|
|
|
|
+-----------+----------------------------------+-------------------+
|
|
| Value | Description | Reference |
|
|
+===========+==================================+===================+
|
|
| 0 | Source Route (DEPRECATED) | [[IPV6]][RFC5095] |
|
|
+-----------+----------------------------------+-------------------+
|
|
| 1 | Nimrod (DEPRECATED 2009-05-06) | |
|
|
+-----------+----------------------------------+-------------------+
|
|
| 2 | Type 2 Routing Header | [RFC6275] |
|
|
+-----------+----------------------------------+-------------------+
|
|
| 3 | RPL Source Route Header | [RFC6554] |
|
|
+-----------+----------------------------------+-------------------+
|
|
| 4 - 252 | Unassigned | |
|
|
+-----------+----------------------------------+-------------------+
|
|
| 253 | RFC3692-style Experiment 1 [2] | [RFC4727] |
|
|
+-----------+----------------------------------+-------------------+
|
|
| 254 | RFC3692-style Experiment 2 [2] | [RFC4727] |
|
|
+-----------+----------------------------------+-------------------+
|
|
| 255 | Reserved | |
|
|
+-----------+----------------------------------+-------------------+
|
|
"""
|
|
|
|
TYPE = inet.IPPROTO_ROUTING
|
|
|
|
_OFFSET_LEN = struct.calcsize('!2B')
|
|
|
|
# IPv6 Routing Header Type
|
|
ROUTING_TYPE_2 = 0x02
|
|
ROUTING_TYPE_3 = 0x03
|
|
|
|
@classmethod
|
|
def parser(cls, buf):
|
|
(type_, ) = struct.unpack_from('!B', buf, cls._OFFSET_LEN)
|
|
switch = {
|
|
# TODO: make parsers of type2.
|
|
cls.ROUTING_TYPE_2: None,
|
|
cls.ROUTING_TYPE_3: routing_type3
|
|
}
|
|
cls_ = switch.get(type_)
|
|
if cls_:
|
|
return cls_.parser(buf)
|
|
else:
|
|
return None
|
|
|
|
|
|
class routing_type3(header):
|
|
"""
|
|
An IPv6 Routing Header for Source Routes with the RPL (RFC 6554)
|
|
encoder/decoder class.
|
|
|
|
This is used with ryu.lib.packet.ipv6.ipv6.
|
|
|
|
An instance has the following attributes at least.
|
|
Most of them are same to the on-wire counterparts but in host byte order.
|
|
__init__ takes the corresponding args in this order.
|
|
|
|
.. tabularcolumns:: |l|L|
|
|
|
|
============== =======================================
|
|
Attribute Description
|
|
============== =======================================
|
|
nxt Next Header
|
|
size The length of the Routing header,
|
|
not include the first 8 octet.
|
|
(0 means automatically-calculate when encoding)
|
|
type Identifies the particular Routing header variant.
|
|
seg Number of route segments remaining.
|
|
cmpi Number of prefix octets from segments 1 through n-1.
|
|
cmpe Number of prefix octets from segment n.
|
|
pad Number of octets that are used for padding
|
|
after Address[n] at the end of the SRH.
|
|
adrs Vector of addresses, numbered 1 to n.
|
|
============== =======================================
|
|
"""
|
|
|
|
_PACK_STR = '!BBBBBB2x'
|
|
_MIN_LEN = struct.calcsize(_PACK_STR)
|
|
_TYPE = {
|
|
'asciilist': [
|
|
'adrs'
|
|
]
|
|
}
|
|
|
|
def __init__(self, nxt=inet.IPPROTO_TCP, size=0,
|
|
type_=3, seg=0, cmpi=0, cmpe=0, adrs=None):
|
|
super(routing_type3, self).__init__(nxt)
|
|
self.size = size
|
|
self.type_ = type_
|
|
self.seg = seg
|
|
self.cmpi = cmpi
|
|
self.cmpe = cmpe
|
|
adrs = adrs or []
|
|
assert isinstance(adrs, list)
|
|
self.adrs = adrs
|
|
self._pad = (8 - ((len(self.adrs) - 1) * (16 - self.cmpi) +
|
|
(16 - self.cmpe) % 8)) % 8
|
|
|
|
@classmethod
|
|
def _get_size(cls, size):
|
|
return (int(size) + 1) * 8
|
|
|
|
@classmethod
|
|
def parser(cls, buf):
|
|
(nxt, size, type_, seg, cmp_, pad) = struct.unpack_from(
|
|
cls._PACK_STR, buf)
|
|
data = cls._MIN_LEN
|
|
header_len = cls._get_size(size)
|
|
cmpi = int(cmp_ >> 4)
|
|
cmpe = int(cmp_ & 0xf)
|
|
pad = int(pad >> 4)
|
|
adrs = []
|
|
if size:
|
|
# Address[1..n-1] has size (16 - CmprI) octets
|
|
adrs_len_i = 16 - cmpi
|
|
# Address[n] has size (16 - CmprE) octets
|
|
adrs_len_e = 16 - cmpe
|
|
form_i = "%ds" % adrs_len_i
|
|
form_e = "%ds" % adrs_len_e
|
|
while data < (header_len - (adrs_len_e + pad)):
|
|
(adr, ) = struct.unpack_from(form_i, buf[data:])
|
|
adr = (b'\x00' * cmpi) + adr
|
|
adrs.append(addrconv.ipv6.bin_to_text(adr))
|
|
data += adrs_len_i
|
|
(adr, ) = struct.unpack_from(form_e, buf[data:])
|
|
adr = (b'\x00' * cmpe) + adr
|
|
adrs.append(addrconv.ipv6.bin_to_text(adr))
|
|
return cls(nxt, size, type_, seg, cmpi, cmpe, adrs)
|
|
|
|
def serialize(self):
|
|
if self.size == 0:
|
|
self.size = ((len(self.adrs) - 1) * (16 - self.cmpi) +
|
|
(16 - self.cmpe) + self._pad) // 8
|
|
buf = struct.pack(self._PACK_STR, self.nxt, self.size,
|
|
self.type_, self.seg, (self.cmpi << 4) | self.cmpe,
|
|
self._pad << 4)
|
|
buf = bytearray(buf)
|
|
if self.size:
|
|
form_i = "%ds" % (16 - self.cmpi)
|
|
form_e = "%ds" % (16 - self.cmpe)
|
|
slice_i = slice(self.cmpi, 16)
|
|
slice_e = slice(self.cmpe, 16)
|
|
for adr in self.adrs[:-1]:
|
|
buf.extend(
|
|
struct.pack(
|
|
form_i, addrconv.ipv6.text_to_bin(adr)[slice_i]))
|
|
buf.extend(struct.pack(
|
|
form_e,
|
|
addrconv.ipv6.text_to_bin(self.adrs[-1])[slice_e]))
|
|
return buf
|
|
|
|
def __len__(self):
|
|
return routing_type3._get_size(self.size)
|
|
|
|
|
|
@ipv6.register_header_type(inet.IPPROTO_FRAGMENT)
|
|
class fragment(header):
|
|
r"""IPv6 (RFC 2460) fragment header encoder/decoder class.
|
|
|
|
This is used with ryu.lib.packet.ipv6.ipv6.
|
|
|
|
An instance has the following attributes at least.
|
|
Most of them are same to the on-wire counterparts but in host byte order.
|
|
__init__ takes the corresponding args in this order.
|
|
|
|
.. tabularcolumns:: |l|L|
|
|
|
|
============== =======================================
|
|
Attribute Description
|
|
============== =======================================
|
|
nxt Next Header
|
|
offset offset, in 8-octet units, relative to
|
|
the start of the fragmentable part of
|
|
the original packet.
|
|
more 1 means more fragments follow;
|
|
0 means last fragment.
|
|
id\_ packet identification value.
|
|
============== =======================================
|
|
"""
|
|
TYPE = inet.IPPROTO_FRAGMENT
|
|
|
|
_PACK_STR = '!BxHI'
|
|
_MIN_LEN = struct.calcsize(_PACK_STR)
|
|
|
|
def __init__(self, nxt=inet.IPPROTO_TCP, offset=0, more=0, id_=0):
|
|
super(fragment, self).__init__(nxt)
|
|
self.offset = offset
|
|
self.more = more
|
|
self.id_ = id_
|
|
|
|
@classmethod
|
|
def parser(cls, buf):
|
|
(nxt, off_m, id_) = struct.unpack_from(cls._PACK_STR, buf)
|
|
offset = off_m >> 3
|
|
more = off_m & 0x1
|
|
return cls(nxt, offset, more, id_)
|
|
|
|
def serialize(self):
|
|
off_m = (self.offset << 3 | self.more)
|
|
buf = struct.pack(self._PACK_STR, self.nxt, off_m, self.id_)
|
|
return buf
|
|
|
|
def __len__(self):
|
|
return self._MIN_LEN
|
|
|
|
|
|
@ipv6.register_header_type(inet.IPPROTO_AH)
|
|
class auth(header):
|
|
"""IP Authentication header (RFC 2402) encoder/decoder class.
|
|
|
|
This is used with ryu.lib.packet.ipv6.ipv6.
|
|
|
|
An instance has the following attributes at least.
|
|
Most of them are same to the on-wire counterparts but in host byte order.
|
|
__init__ takes the corresponding args in this order.
|
|
|
|
.. tabularcolumns:: |l|L|
|
|
|
|
============== =======================================
|
|
Attribute Description
|
|
============== =======================================
|
|
nxt Next Header
|
|
size the length of the Authentication Header
|
|
in 64-bit words, subtracting 1.
|
|
spi security parameters index.
|
|
seq sequence number.
|
|
data authentication data.
|
|
============== =======================================
|
|
"""
|
|
TYPE = inet.IPPROTO_AH
|
|
|
|
_PACK_STR = '!BB2xII'
|
|
_MIN_LEN = struct.calcsize(_PACK_STR)
|
|
|
|
def __init__(self, nxt=inet.IPPROTO_TCP, size=2, spi=0, seq=0,
|
|
data=b'\x00\x00\x00\x00'):
|
|
super(auth, self).__init__(nxt)
|
|
assert data is not None
|
|
self.size = size
|
|
self.spi = spi
|
|
self.seq = seq
|
|
self.data = data
|
|
|
|
@classmethod
|
|
def _get_size(cls, size):
|
|
return (int(size) + 2) * 4
|
|
|
|
@classmethod
|
|
def parser(cls, buf):
|
|
(nxt, size, spi, seq) = struct.unpack_from(cls._PACK_STR, buf)
|
|
form = "%ds" % (cls._get_size(size) - cls._MIN_LEN)
|
|
(data, ) = struct.unpack_from(form, buf, cls._MIN_LEN)
|
|
return cls(nxt, size, spi, seq, data)
|
|
|
|
def serialize(self):
|
|
buf = struct.pack(self._PACK_STR, self.nxt, self.size, self.spi,
|
|
self.seq)
|
|
buf = bytearray(buf)
|
|
form = "%ds" % (auth._get_size(self.size) - self._MIN_LEN)
|
|
buf.extend(struct.pack(form, self.data))
|
|
return buf
|
|
|
|
def __len__(self):
|
|
return auth._get_size(self.size)
|
|
|
|
|
|
ipv6.set_classes(ipv6._IPV6_EXT_HEADER_TYPE)
|