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#!/usr/bin/env python
# http://trac.secdev.org/scapy/ticket/353
# scapy.contrib.description = IKEv2
# scapy.contrib.status = loads
from scapy.all import *
import logging
## Modified from the original ISAKMP code by Yaron Sheffer <yaronf.ietf@gmail.com>, June 2010.
import struct
from scapy.packet import *
from scapy.fields import *
from scapy.ansmachine import *
from scapy.layers.inet import IP,UDP
from scapy.sendrecv import sr
# see http://www.iana.org/assignments/ikev2-parameters for details
IKEv2AttributeTypes= { "Encryption": (1, { "DES-IV64" : 1,
"DES" : 2,
"3DES" : 3,
"RC5" : 4,
"IDEA" : 5,
"CAST" : 6,
"Blowfish" : 7,
"3IDEA" : 8,
"DES-IV32" : 9,
"AES-CBC" : 12,
"AES-CTR" : 13,
"AES-CCM-8" : 14,
"AES-CCM-12" : 15,
"AES-CCM-16" : 16,
"AES-GCM-8ICV" : 18,
"AES-GCM-12ICV" : 19,
"AES-GCM-16ICV" : 20,
"Camellia-CBC" : 23,
"Camellia-CTR" : 24,
"Camellia-CCM-8ICV" : 25,
"Camellia-CCM-12ICV" : 26,
"Camellia-CCM-16ICV" : 27,
}, 0),
"PRF": (2, {"PRF_HMAC_MD5":1,
"PRF_HMAC_SHA1":2,
"PRF_HMAC_TIGER":3,
"PRF_AES128_XCBC":4,
"PRF_HMAC_SHA2_256":5,
"PRF_HMAC_SHA2_384":6,
"PRF_HMAC_SHA2_512":7,
"PRF_AES128_CMAC":8,
}, 0),
"Integrity": (3, { "HMAC-MD5-96": 1,
"HMAC-SHA1-96": 2,
"DES-MAC": 3,
"KPDK-MD5": 4,
"AES-XCBC-96": 5,
"HMAC-MD5-128": 6,
"HMAC-SHA1-160": 7,
"AES-CMAC-96": 8,
"AES-128-GMAC": 9,
"AES-192-GMAC": 10,
"AES-256-GMAC": 11,
"SHA2-256-128": 12,
"SHA2-384-192": 13,
"SHA2-512-256": 14,
}, 0),
"GroupDesc": (4, { "768MODPgr" : 1,
"1024MODPgr" : 2,
"1536MODPgr" : 5,
"2048MODPgr" : 14,
"3072MODPgr" : 15,
"4096MODPgr" : 16,
"6144MODPgr" : 17,
"8192MODPgr" : 18,
"256randECPgr" : 19,
"384randECPgr" : 20,
"521randECPgr" : 21,
"1024MODP160POSgr" : 22,
"2048MODP224POSgr" : 23,
"2048MODP256POSgr" : 24,
"192randECPgr" : 25,
"224randECPgr" : 26,
}, 0),
"Extended Sequence Number": (5, {"No ESN": 0,
"ESN": 1, }, 0),
}
IKEv2NotifyMessageTypes = {
1 : "UNSUPPORTED_CRITICAL_PAYLOAD",
4 : "INVALID_IKE_SPI",
5 : "INVALID_MAJOR_VERSION",
7 : "INVALID_SYNTAX",
9 : "INVALID_MESSAGE_ID",
11 : "INVALID_SPI",
14 : "NO_PROPOSAL_CHOSEN",
17 : "INVALID_KE_PAYLOAD",
24 : "AUTHENTICATION_FAILED",
34 : "SINGLE_PAIR_REQUIRED",
35 : "NO_ADDITIONAL_SAS",
36 : "INTERNAL_ADDRESS_FAILURE",
37 : "FAILED_CP_REQUIRED",
38 : "TS_UNACCEPTABLE",
39 : "INVALID_SELECTORS",
40 : "UNACCEPTABLE_ADDRESSES",
41 : "UNEXPECTED_NAT_DETECTED",
42 : "USE_ASSIGNED_HoA",
43 : "TEMPORARY_FAILURE",
44 : "CHILD_SA_NOT_FOUND",
45 : "INVALID_GROUP_ID",
46 : "AUTHORIZATION_FAILED",
16384 : "INITIAL_CONTACT",
16385 : "SET_WINDOW_SIZE",
16386 : "ADDITIONAL_TS_POSSIBLE",
16387 : "IPCOMP_SUPPORTED",
16388 : "NAT_DETECTION_SOURCE_IP",
16389 : "NAT_DETECTION_DESTINATION_IP",
16390 : "COOKIE",
16391 : "USE_TRANSPORT_MODE",
16392 : "HTTP_CERT_LOOKUP_SUPPORTED",
16393 : "REKEY_SA",
16394 : "ESP_TFC_PADDING_NOT_SUPPORTED",
16395 : "NON_FIRST_FRAGMENTS_ALSO",
16396 : "MOBIKE_SUPPORTED",
16397 : "ADDITIONAL_IP4_ADDRESS",
16398 : "ADDITIONAL_IP6_ADDRESS",
16399 : "NO_ADDITIONAL_ADDRESSES",
16400 : "UPDATE_SA_ADDRESSES",
16401 : "COOKIE2",
16402 : "NO_NATS_ALLOWED",
16403 : "AUTH_LIFETIME",
16404 : "MULTIPLE_AUTH_SUPPORTED",
16405 : "ANOTHER_AUTH_FOLLOWS",
16406 : "REDIRECT_SUPPORTED",
16407 : "REDIRECT",
16408 : "REDIRECTED_FROM",
16409 : "TICKET_LT_OPAQUE",
16410 : "TICKET_REQUEST",
16411 : "TICKET_ACK",
16412 : "TICKET_NACK",
16413 : "TICKET_OPAQUE",
16414 : "LINK_ID",
16415 : "USE_WESP_MODE",
16416 : "ROHC_SUPPORTED",
16417 : "EAP_ONLY_AUTHENTICATION",
16418 : "CHILDLESS_IKEV2_SUPPORTED",
16419 : "QUICK_CRASH_DETECTION",
16420 : "IKEV2_MESSAGE_ID_SYNC_SUPPORTED",
16421 : "IPSEC_REPLAY_COUNTER_SYNC_SUPPORTED",
16422 : "IKEV2_MESSAGE_ID_SYNC",
16423 : "IPSEC_REPLAY_COUNTER_SYNC",
16424 : "SECURE_PASSWORD_METHODS",
16425 : "PSK_PERSIST",
16426 : "PSK_CONFIRM",
16427 : "ERX_SUPPORTED",
16428 : "IFOM_CAPABILITY",
16429 : "SENDER_REQUEST_ID",
16430 : "IKEV2_FRAGMENTATION_SUPPORTED",
16431 : "SIGNATURE_HASH_ALGORITHMS",
16432 : "CLONE_IKE_SA_SUPPORTED",
16433 : "CLONE_IKE_SA"
}
IKEv2CertificateEncodings = {
1 : "PKCS #7 wrapped X.509 certificate",
2 : "PGP Certificate",
3 : "DNS Signed Key",
4 : "X.509 Certificate - Signature",
6 : "Kerberos Token",
7 : "Certificate Revocation List (CRL)",
8 : "Authority Revocation List (ARL)",
9 : "SPKI Certificate",
10 : "X.509 Certificate - Attribute",
11 : "Raw RSA Key",
12 : "Hash and URL of X.509 certificate",
13 : "Hash and URL of X.509 bundle"
}
# the name 'IKEv2TransformTypes' is actually a misnomer (since the table
# holds info for all IKEv2 Attribute types, not just transforms, but we'll
# keep it for backwards compatibility... for now at least
IKEv2TransformTypes = IKEv2AttributeTypes
IKEv2TransformNum = {}
for n in IKEv2TransformTypes:
val = IKEv2TransformTypes[n]
tmp = {}
for e in val[1]:
tmp[val[1][e]] = e
IKEv2TransformNum[val[0]] = tmp
IKEv2Transforms = {}
for n in IKEv2TransformTypes:
IKEv2Transforms[IKEv2TransformTypes[n][0]]=n
del(n)
del(e)
del(tmp)
del(val)
# Note: Transform and Proposal can only be used inside the SA payload
IKEv2_payload_type = ["None", "", "Proposal", "Transform"]
IKEv2_payload_type.extend([""] * 29)
IKEv2_payload_type.extend(["SA","KE","IDi","IDr", "CERT","CERTREQ","AUTH","Nonce","Notify","Delete",
"VendorID","TSi","TSr","Encrypted","CP","EAP"])
IKEv2_exchange_type = [""] * 34
IKEv2_exchange_type.extend(["IKE_SA_INIT","IKE_AUTH","CREATE_CHILD_SA",
"INFORMATIONAL", "IKE_SESSION_RESUME"])
class IKEv2_class(Packet):
def guess_payload_class(self, payload):
np = self.next_payload
logging.debug("For IKEv2_class np=%d" % np)
if np == 0:
return conf.raw_layer
elif np < len(IKEv2_payload_type):
pt = IKEv2_payload_type[np]
logging.debug(globals().get("IKEv2_payload_%s" % pt, IKEv2_payload))
return globals().get("IKEv2_payload_%s" % pt, IKEv2_payload)
else:
return IKEv2_payload
class IKEv2(IKEv2_class): # rfc4306
name = "IKEv2"
fields_desc = [
StrFixedLenField("init_SPI","",8),
StrFixedLenField("resp_SPI","",8),
ByteEnumField("next_payload",0,IKEv2_payload_type),
XByteField("version",0x20), # IKEv2, right?
ByteEnumField("exch_type",0,IKEv2_exchange_type),
FlagsField("flags",0, 8, ["res0","res1","res2","Initiator","Version","Response","res6","res7"]),
IntField("id",0),
IntField("length",None)
]
def guess_payload_class(self, payload):
if self.flags & 1:
return conf.raw_layer
return IKEv2_class.guess_payload_class(self, payload)
def answers(self, other):
if isinstance(other, IKEv2):
if other.init_SPI == self.init_SPI:
return 1
return 0
def post_build(self, p, pay):
p += pay
if self.length is None:
p = p[:24]+struct.pack("!I",len(p))+p[28:]
return p
class IKEv2_Key_Length_Attribute(IntField):
# We only support the fixed-length Key Length attribute (the only one currently defined)
name="key length"
def __init__(self, name):
IntField.__init__(self, name, 0x800E0000)
def i2h(self, pkt, x):
return IntField.i2h(self, pkt, x & 0xFFFF)
def h2i(self, pkt, x):
return IntField.h2i(self, pkt, x | 0x800E0000)
class IKEv2_payload_Transform(IKEv2_class):
name = "IKE Transform"
fields_desc = [
ByteEnumField("next_payload",None,{0:"last", 3:"Transform"}),
ByteField("res",0),
ShortField("length",8),
ByteEnumField("transform_type",None,IKEv2Transforms),
ByteField("res2",0),
MultiEnumField("transform_id",None,IKEv2TransformNum,depends_on=lambda pkt:pkt.transform_type,fmt="H"),
ConditionalField(IKEv2_Key_Length_Attribute("key_length"), lambda pkt: pkt.length > 8),
]
class IKEv2_payload_Proposal(IKEv2_class):
name = "IKEv2 Proposal"
fields_desc = [
ByteEnumField("next_payload",None,{0:"last", 2:"Proposal"}),
ByteField("res",0),
FieldLenField("length",None,"trans","H", adjust=lambda pkt,x:x+8),
ByteField("proposal",1),
ByteEnumField("proto",1,{1:"IKEv2"}),
FieldLenField("SPIsize",None,"SPI","B"),
ByteField("trans_nb",None),
StrLenField("SPI","",length_from=lambda x:x.SPIsize),
PacketLenField("trans",conf.raw_layer(),IKEv2_payload_Transform,length_from=lambda x:x.length-8),
]
class IKEv2_payload(IKEv2_class):
name = "IKEv2 Payload"
fields_desc = [
ByteEnumField("next_payload",None,IKEv2_payload_type),
FlagsField("flags",0, 8, ["critical","res1","res2","res3","res4","res5","res6","res7"]),
FieldLenField("length",None,"load","H", adjust=lambda pkt,x:x+4),
StrLenField("load","",length_from=lambda x:x.length-4),
]
class IKEv2_payload_VendorID(IKEv2_class):
name = "IKEv2 Vendor ID"
fields_desc = [
ByteEnumField("next_payload",None,IKEv2_payload_type),
ByteField("res",0),
FieldLenField("length",None,"vendorID","H", adjust=lambda pkt,x:x+4),
StrLenField("vendorID","",length_from=lambda x:x.length-4),
]
class IKEv2_payload_Delete(IKEv2_class):
name = "IKEv2 Vendor ID"
fields_desc = [
ByteEnumField("next_payload",None,IKEv2_payload_type),
ByteField("res",0),
FieldLenField("length",None,"vendorID","H", adjust=lambda pkt,x:x+4),
StrLenField("vendorID","",length_from=lambda x:x.length-4),
]
class IKEv2_payload_SA(IKEv2_class):
name = "IKEv2 SA"
fields_desc = [
ByteEnumField("next_payload",None,IKEv2_payload_type),
ByteField("res",0),
FieldLenField("length",None,"prop","H", adjust=lambda pkt,x:x+4),
PacketLenField("prop",conf.raw_layer(),IKEv2_payload_Proposal,length_from=lambda x:x.length-4),
]
class IKEv2_payload_Nonce(IKEv2_class):
name = "IKEv2 Nonce"
fields_desc = [
ByteEnumField("next_payload",None,IKEv2_payload_type),
ByteField("res",0),
FieldLenField("length",None,"load","H", adjust=lambda pkt,x:x+4),
StrLenField("load","",length_from=lambda x:x.length-4),
]
class IKEv2_payload_Notify(IKEv2_class):
name = "IKEv2 Notify"
fields_desc = [
ByteEnumField("next_payload",None,IKEv2_payload_type),
ByteField("res",0),
FieldLenField("length",None,"load","H", adjust=lambda pkt,x:x+8),
ByteEnumField("proto",None,{0:"Reserved",1:"IKE",2:"AH", 3:"ESP"}),
FieldLenField("SPIsize",None,"SPI","B"),
ShortEnumField("type",0,IKEv2NotifyMessageTypes),
StrLenField("SPI","",length_from=lambda x:x.SPIsize),
StrLenField("load","",length_from=lambda x:x.length-8),
]
class IKEv2_payload_KE(IKEv2_class):
name = "IKEv2 Key Exchange"
fields_desc = [
ByteEnumField("next_payload",None,IKEv2_payload_type),
ByteField("res",0),
FieldLenField("length",None,"load","H", adjust=lambda pkt,x:x+8),
ShortEnumField("group", 0, IKEv2TransformTypes['GroupDesc'][1]),
ShortField("res2", 0),
StrLenField("load","",length_from=lambda x:x.length-8),
]
class IKEv2_payload_IDi(IKEv2_class):
name = "IKEv2 Identification - Initiator"
fields_desc = [
ByteEnumField("next_payload",None,IKEv2_payload_type),
ByteField("res",0),
FieldLenField("length",None,"load","H",adjust=lambda pkt,x:x+8),
ByteEnumField("IDtype",1,{1:"IPv4_addr", 2:"FQDN", 3:"Email_addr", 5:"IPv6_addr", 11:"Key"}),
ByteEnumField("ProtoID",0,{0:"Unused"}),
ShortEnumField("Port",0,{0:"Unused"}),
# IPField("IdentData","127.0.0.1"),
StrLenField("load","",length_from=lambda x:x.length-8),
]
class IKEv2_payload_IDr(IKEv2_class):
name = "IKEv2 Identification - Responder"
fields_desc = [
ByteEnumField("next_payload",None,IKEv2_payload_type),
ByteField("res",0),
FieldLenField("length",None,"load","H",adjust=lambda pkt,x:x+8),
ByteEnumField("IDtype",1,{1:"IPv4_addr", 2:"FQDN", 3:"Email_addr", 5:"IPv6_addr", 11:"Key"}),
ByteEnumField("ProtoID",0,{0:"Unused"}),
ShortEnumField("Port",0,{0:"Unused"}),
# IPField("IdentData","127.0.0.1"),
StrLenField("load","",length_from=lambda x:x.length-8),
]
class IKEv2_payload_Encrypted(IKEv2_class):
name = "IKEv2 Encrypted and Authenticated"
fields_desc = [
ByteEnumField("next_payload",None,IKEv2_payload_type),
ByteField("res",0),
FieldLenField("length",None,"load","H",adjust=lambda pkt,x:x+4),
StrLenField("load","",length_from=lambda x:x.length-4),
]
class IKEv2_payload_CERTREQ(IKEv2_class):
name = "IKEv2 Certificate Request"
fields_desc = [
ByteEnumField("next_payload",None,IKEv2_payload_type),
ByteField("res",0),
FieldLenField("length",None,"cert_data","H",adjust=lambda pkt,x:x+5),
ByteEnumField("cert_type",0,IKEv2CertificateEncodings),
StrLenField("cert_data","",length_from=lambda x:x.length-5),
]
class IKEv2_payload_CERT(IKEv2_class):
name = "IKEv2 Certificate"
fields_desc = [
ByteEnumField("next_payload",None,IKEv2_payload_type),
ByteField("res",0),
FieldLenField("length",None,"cert_data","H",adjust=lambda pkt,x:x+5),
ByteEnumField("cert_type",0,IKEv2CertificateEncodings),
StrLenField("cert_data","",length_from=lambda x:x.length-5),
]
IKEv2_payload_classes = {}
for i in range(len(IKEv2_payload_type)):
name = "IKEv2_payload_%s" % IKEv2_payload_type[i]
if name in globals():
IKEv2_payload_classes[globals()[name]] = i
for i in IKEv2_payload_classes:
i.overload_fields = {IKEv2 : {"next_payload" : IKEv2_payload_classes[i]}}
for j in IKEv2_payload_classes:
i.overload_fields[j] = {"next_payload" : IKEv2_payload_classes[i]}
del(i)
del(j)
del(name)
split_layers(UDP, ISAKMP, sport=500)
split_layers(UDP, ISAKMP, dport=500)
bind_layers( UDP, IKEv2, dport=500, sport=500) # TODO: distinguish IKEv1/IKEv2
def ikev2scan(ip):
return sr(IP(dst=ip)/UDP()/IKEv2(init_SPI=RandString(8),
exch_type=34)/IKEv2_payload_SA(prop=IKEv2_payload_Proposal()))
# conf.debug_dissector = 1
if __name__ == "__main__":
interact(mydict=globals(), mybanner="IKEv2 alpha-level protocol implementation")
|