Feature Request: add "raw" rule command

[gzarkadas]

Please, consider adding a "raw" rule command in ufw that would allow adding a direct iptables command to user rules.

The rationale for implementing this as a rule and not resorting to manipulate the ufw framework is simple: rules are shown when `ufw status` is issued; ufw framework actions are not. Not all things
should be kept at the dark. Having a raw rule command for the occasional "advanced" manipulation and be able to see it printed with `ufw status` is far more uncomplicated than editing files with iptables-restore format.

The parsing of the command arguments would proceed like this:

if the first argument after "ufw raw" is not (brackets denote a character range) "-[ADEFINRX]"
then
    the underlying iptables' command is: -A ufw-user-input {all arguments}
else
    the second argument is a chain
    the underlying iptables' command is: -[ADEFINRX] chain {3rd and rest arguments}

The chain operations set can be limited; basically what is needed is the ability to create a new chain and add to it, so that it can be specified as target in a raw command. Also it can (and probably should) restricted only to user-supplied chains.

The benefit of implementing such a feature is that it provides a single service point for many feature requests; for example, it would also provide a usable solution to bugs #801833 and #1571579. That would keep low the need to implement additional future parser objects and commands, each for a specific subset of all that can be accomplished with raw commands.

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ufw version: 0.36
distribution: Devuan chimarea/ceres

[Jamie Strandboge (jdstrand)]

I agree this would be a nice feature.