1.6 TCPFlags Objects

1.6 TCPFlags Objects

A TCPFlags object represents the eight bits of flags from a TCP session.

class TCPFlags( value)

The constructor takes either a TCPFlags value, a string, or an integer. If a TCPFlags value, it returns a copy of that value. If an integer, the integer should represent the 8-bit representation of the flags. If a string, the string should consist of a concatenation of zero or more of the characters "F", "S", "R", "P", "A", "U", "E", and "C"--upper or lower-case--representing the FIN, SYN, RST, PSH, ACK, URG, ECE, and CWR flags. Spaces in the string are ignored.

Examples:

>>> a = TCPFlags('SA')
>>> b = TCPFlags(5)

Instance attributes (read-only):

Attribute	Value
`FIN`	`True` if the FIN flag is set, `False` otherwise
`SYN`	`True` if the SYN flag is set, `False` otherwise
`RST`	`True` if the RST flag is set, `False` otherwise
`PSH`	`True` if the PSH flag is set, `False` otherwise
`ACK`	`True` if the ACK flag is set, `False` otherwise
`URG`	`True` if the URG flag is set, `False` otherwise
`ECE`	`True` if the ECE flag is set, `False` otherwise
`CWR`	`True` if the CWR flag is set, `False` otherwise

Supported operations:

Operation	Result
`f`	The bitwise inversion (not) of `f`
`f1 & f2`	The bitwise intersection (and) of the flags from `f1` and `f2`
`f1 \| f2`	The bitwise union (or) of the flags from `f1` and `f2`
`f1 ^ f2`	The bitwise exclusive disjunction (xor) of the flags from `f1` and `f2`
`int(f)`	The integer value of the flags `f`
`f`	Can be used as a truth value with any flag set == `True`, `False` otherwise

Constants:

The following constants are defined:

Constant	Meaning
`FIN`	A TCPFlags value with only the FIN flags set
`SYN`	A TCPFlags value with only the SYN flags set
`RST`	A TCPFlags value with only the RST flags set
`PSH`	A TCPFlags value with only the PSH flags set
`ACK`	A TCPFlags value with only the ACK flags set
`URG`	A TCPFlags value with only the URG flags set
`ECE`	A TCPFlags value with only the ECE flags set
`CWR`	A TCPFlags value with only the CWR flags set

Supported methods:

matches( flagmask)

Given a flagmask of the form "flags/mask", returns True if if the flags of self match flags after being masked with mask, False otherwise.

Given a flagmask without the "/", checks for literal equality, as if the mask contained all flags.

__str__( )

For an TCPFlags object f, str(f) returns the a string representation of the flags set in f.