Repository: secdev/scapy

Issue:
BIER support (from https://tools.ietf.org/html/draft-ietf-bier-mpls-e…
…ncapsulation-12)

Signed-off-by: Neale Ranns <neale.ranns@cisco.com>


Discussion:

Resolving patch:
diff --git a/scapy/contrib/bier.py b/scapy/contrib/bier.py
new file mode 100644
--- /dev/null
+++ b/scapy/contrib/bier.py
@@ -0,0 +1,68 @@
+# This file is part of Scapy
+# Scapy is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 2 of the License, or
+# any later version.
+#
+# Scapy is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with Scapy. If not, see <http://www.gnu.org/licenses/>.
+
+# scapy.contrib.description = BIER
+# scapy.contrib.status = loads
+
+from scapy.packet import *
+from scapy.fields import *
+from scapy.layers.inet import IP, UDP
+from scapy.layers.inet6 import IPv6
+
+
+class BIERLength:
+    BIER_LEN_64 = 0
+    BIER_LEN_128 = 1
+    BIER_LEN_256 = 2
+    BIER_LEN_512 = 3
+    BIER_LEN_1024 = 4
+
+
+BIERnhcls = {1: "MPLS",
+             2: "MPLS",
+             4: "IPv4",
+             5: "IPv6"}
+
+
+class BIFT(Packet):
+    name = "BIFT"
+    fields_desc = [BitField("bsl", BIERLength.BIER_LEN_256, 4),
+                   BitField("sd", 0, 8),
+                   BitField("set", 0, 8),
+                   BitField("cos", 0, 3),
+                   BitField("s", 1, 1),
+                   ByteField("ttl", 0)]
+
+
+class BIER(Packet):
+    name = "BIER"
+    fields_desc = [BitField("id", 5, 4),
+                   BitField("version", 0, 4),
+                   BitFieldLenField("length", BIERLength.BIER_LEN_256, 4,
+                                    length_of=lambda x:(x.BitString >> 8)),
+                   BitField("entropy", 0, 20),
+                   BitField("OAM", 0, 2),
+                   BitField("RSV", 0, 2),
+                   BitField("DSCP", 0, 6),
+                   BitEnumField("Proto", 2, 6, BIERnhcls),
+                   ShortField("BFRID", 0),
+                   StrLenField("BitString",
+                               "",
+                               length_from=lambda x:(8 << x.length))]
+
+
+bind_layers(BIER, IP,   Proto=4)
+bind_layers(BIER, IPv6, Proto=5)
+bind_layers(UDP,  BIFT, dport=8138)
+bind_layers(BIFT, BIER)
diff --git a/scapy/contrib/mpls.py b/scapy/contrib/mpls.py
--- a/scapy/contrib/mpls.py
+++ b/scapy/contrib/mpls.py
@@ -18,6 +18,7 @@
 from scapy.packet import Packet, bind_layers, Padding
 from scapy.fields import BitField, ByteField, ShortField
 from scapy.layers.inet import IP
+from scapy.contrib.bier import BIER
 from scapy.layers.inet6 import IPv6
 from scapy.layers.l2 import Ether, GRE
 from scapy.compat import orb
@@ -49,6 +50,8 @@ def guess_payload_class(self, payload):
            ip_version = (orb(payload[0]) >> 4) & 0xF
            if ip_version == 4:
                return IP
+           elif ip_version == 5:
+               return BIER
            elif ip_version == 6:
                return IPv6
            else:


Test patch: