Evil Bit Chain

This module contains the EvilChain analysis chain which can be used by PATHspider’s Observer for recording Evil Bit connectivity [RFC3514] details.

class pathspider.chains.evil.EvilChain[source]
Field Name Type Meaning
evilbit_syn_fwd bool True if the evil bit was set in the IP header for a TCP SYN packet in the forward direction, false otherwise
evilbit_syn_fwd bool True if the evil bit was set in the IP header for a TCP SYN packet in the reverse direction, false otherwise
evilbit_data_fwd bool True if the evil bit was set in the IP header for a non-TCP packet in the forward direction, false otherwise
evilbit_data_rev bool True if the evil bit was set in the IP header for a non-TCP packet in the reverse direction, false otherwise
ip4(rec, ip, rev)[source]

Records evil bit markings from an IPv4 header.

Evil Bit Marking
For either TCP_SYN packets or non-TCP or TCP with payload packets the relevant field will record whether the Evil Bit was set.
Parameters:
  • rec (dict) – the flow record
  • ip (plt.ip) – the IPv4 packet that was observed to be part of this flow
  • rev (bool) – True if the packet was in the reverse direction, False if in the forward direction
Returns:

Always True

Return type:

bool

new_flow(rec, ip)[source]

For a new flow, all fields will be initialised to None.

Parameters:
  • rec (dict) – the flow record
  • ip (plt.ip or plt.ip6) – the IP or IPv6 packet that triggered the creation of a new flow record
Returns:

Always True

Return type:

bool