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diff --git a/scapy/layers/inet6.py b/scapy/layers/inet6.py
--- a/scapy/layers/inet6.py 2017-06-01 14:04:18.160881034 +0200
+++ b/scapy/layers/inet6.py 2017-06-02 09:08:40.133800208 +0200
@@ -369,6 +369,8 @@
return Raw
elif self.nh == 135 and len(p) > 3: # Mobile IPv6
return _mip6_mhtype2cls.get(ord(p[2]), MIP6MH_Generic)
+ elif self.nh == 43 and ord(p[2]) == 4: # Segment Routing header
+ return IPv6ExtHdrSegmentRouting
else:
return get_cls(ipv6nhcls.get(self.nh,"Raw"), "Raw")
@@ -430,6 +432,14 @@
sd = strxor(sd, a)
sd = inet_ntop(socket.AF_INET6, sd)
+ if self.nh == 43 and isinstance(self.payload, IPv6ExtHdrSegmentRouting):
+ # With segment routing header (rh == 4), the destination is
+ # the first address of the IPv6 addresses list
+ try:
+ sd = self.addresses[0]
+ except IndexError:
+ sd = self.dst
+
if self.nh == 44 and isinstance(self.payload, IPv6ExtHdrFragment):
nh = self.payload.nh
@@ -489,6 +499,8 @@
return self.payload.answers(other.payload.payload)
elif other.nh == 43 and isinstance(other.payload, IPv6ExtHdrRouting):
return self.payload.answers(other.payload.payload) # Buggy if self.payload is a IPv6ExtHdrRouting
+ elif other.nh == 43 and isinstance(other.payload, IPv6ExtHdrSegmentRouting):
+ return self.payload.answers(other.payload.payload) # Buggy if self.payload is a IPv6ExtHdrRouting
elif other.nh == 60 and isinstance(other.payload, IPv6ExtHdrDestOpt):
return self.payload.payload.answers(other.payload.payload)
elif self.nh == 60 and isinstance(self.payload, IPv6ExtHdrDestOpt): # BU in reply to BRR, for instance
@@ -919,6 +931,148 @@
pkt = pkt[:3]+struct.pack("B", len(self.addresses))+pkt[4:]
return _IPv6ExtHdr.post_build(self, pkt, pay)
+######################### Segment Routing Header ############################
+
+# This implementation is based on draft 06, available at:
+# https://tools.ietf.org/html/draft-ietf-6man-segment-routing-header-06
+
+class IPv6ExtHdrSegmentRoutingTLV(Packet):
+ name = "IPv6 Option Header Segment Routing - Generic TLV"
+ fields_desc = [ ByteField("type", 0),
+ ByteField("len", 0),
+ ByteField("reserved", 0),
+ ByteField("flags", 0),
+ StrLenField("value", "", length_from=lambda pkt: pkt.len) ]
+
+ def extract_padding(self, p):
+ return "",p
+
+ registered_sr_tlv = {}
+ @classmethod
+ def register_variant(cls):
+ cls.registered_sr_tlv[cls.type.default] = cls
+
+ @classmethod
+ def dispatch_hook(cls, pkt=None, *args, **kargs):
+ if pkt:
+ tmp_type = ord(pkt[0])
+ return cls.registered_sr_tlv.get(tmp_type, cls)
+ return cls
+
+
+class IPv6ExtHdrSegmentRoutingTLVIngressNode(IPv6ExtHdrSegmentRoutingTLV):
+ name = "IPv6 Option Header Segment Routing - Ingress Node TLV"
+ fields_desc = [ ByteField("type", 1),
+ ByteField("len", 18),
+ ByteField("reserved", 0),
+ ByteField("flags", 0),
+ IP6Field("ingress_node", "::1") ]
+
+
+class IPv6ExtHdrSegmentRoutingTLVEgressNode(IPv6ExtHdrSegmentRoutingTLV):
+ name = "IPv6 Option Header Segment Routing - Egress Node TLV"
+ fields_desc = [ ByteField("type", 2),
+ ByteField("len", 18),
+ ByteField("reserved", 0),
+ ByteField("flags", 0),
+ IP6Field("egress_node", "::1") ]
+
+
+class IPv6ExtHdrSegmentRoutingTLVPadding(IPv6ExtHdrSegmentRoutingTLV):
+ name = "IPv6 Option Header Segment Routing - Padding TLV"
+ fields_desc = [ ByteField("type", 4),
+ FieldLenField("len", None, length_of="padding", fmt="B"),
+ StrLenField("padding", b"\x00", length_from=lambda pkt: pkt.len) ]
+
+
+class IPv6ExtHdrSegmentRouting(_IPv6ExtHdr):
+ # 0 1 2 3
+ # 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ #+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ #| Next Header | Hdr Ext Len | Routing Type | Segments Left |
+ #+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ #| Last Entry | Flags | Tag |
+ #+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ #| |
+ #| Segment List[0] (128 bits IPv6 address) |
+ #| |
+ #| |
+ #+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ #| |
+ #| |
+ # ...
+ #| |
+ #| |
+ #+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ #| |
+ #| Segment List[n] (128 bits IPv6 address) |
+ #| |
+ #| |
+ #+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ #// //
+ #// Optional Type Length Value objects (variable) //
+ #// //
+ #+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ #
+ # 0 1 2 3 4 5 6 7
+ # +-+-+-+-+-+-+-+-+
+ # |U|P|O|A|H| U |
+ # +-+-+-+-+-+-+-+-+
+
+ name = "IPv6 Segment Routing Extension Header"
+ fields_desc = [ ByteEnumField("nh", 59, ipv6nh),
+ ByteField("len", None),
+ ByteField("type", 4),
+ ByteField("segleft", None),
+ ByteField("lastentry", None),
+ BitField("unused1", 0, 1),
+ BitField("protected", 0, 1),
+ BitField("oam", 0, 1),
+ BitField("alert", 0, 1),
+ BitField("hmac", 0, 1),
+ BitField("unused2", 0, 3),
+ ShortField("tag", 0),
+ IP6ListField("addresses", ["::1"],
+ count_from=lambda pkt: pkt.lastentry+1),
+ PacketListField("tlv_objects", [], IPv6ExtHdrSegmentRoutingTLV,
+ length_from=lambda pkt: 8*pkt.len - 16*(pkt.lastentry+1)) ]
+
+ overload_fields = { IPv6: { "nh": 43 } }
+
+ def post_build(self, pkt, pay):
+
+ if self.len is None:
+
+ # The extension must be align on 8 bytes
+ tmp_mod = (len(pkt) - 8) % 8
+ if tmp_mod == 1:
+ warning("IPv6ExtHdrSegmentRouting(): can't pad 1 byte !")
+ elif tmp_mod >= 2:
+ #Add the padding extension
+ tmp_pad = b"\x00" * (tmp_mod-2)
+ tlv = IPv6ExtHdrSegmentRoutingTLVPadding(padding=tmp_pad)
+ pkt += str(tlv)
+
+ tmp_len = (len(pkt) - 8) / 8
+ pkt = pkt[:1] + struct.pack("B", tmp_len)+ pkt[2:]
+
+ if self.segleft is None:
+ tmp_len = len(self.addresses)
+ if tmp_len:
+ tmp_len -= 1
+ pkt = pkt[:3] + struct.pack("B", tmp_len) + pkt[4:]
+
+ if self.lastentry is None:
+ #km - changed to contain n-1
+ tmp_len = len(self.addresses)
+ if tmp_len:
+ tmp_len -= 1
+ #pkt = pkt[:4] + struct.pack("B", len(self.addresses)) + pkt[5:]
+ pkt = pkt[:4] + struct.pack("B", tmp_len) + pkt[5:]
+
+ return _IPv6ExtHdr.post_build(self, pkt, pay)
+
+
########################### Fragmentation Header ############################
class IPv6ExtHdrFragment(_IPv6ExtHdr):
|
