diff --git a/scapy/contrib/bier.py b/scapy/contrib/bier.py new file mode 100644 index 0000000..e173cdb --- /dev/null +++ b/scapy/contrib/bier.py @@ -0,0 +1,56 @@ +# http://trac.secdev.org/scapy/ticket/31 + +# 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", 0, 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)