RESTRICTIONS:

 - IPv4 only


Each packet may have zero or more "flags" set.  Each flag has a unique purpose and may or may not be included.  The flags are:


Evil


This should not be set, but is available to be as complete as possible!  This is a joke flag as defined and serves no real purposes.  Enabling this will give away that you're modifying packets.


Do Not Fragment (DNF)


If the packet is set with DNF and the packet needs to be fragmented to set this will cause it to be dropped.


More [Fragments] (MF)


The "More" or "More fragments" is set when the packet is fragmented and is automatically cleared on the last packet.



References:

https://en.wikipedia.org/wiki/IPv4#Flags

https://en.wikipedia.org/wiki/Evil_bit