--- /dev/null
+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):
Code Review / vpp.git / blobdiff