Add GRE protocol

[Laurent Dinclaux]

Enabling firewall will prevent connecting to remote PPTP server.

We need a way to enable the GRE protocol using GUFW. Only TCP and UDP are available to selection for now, even in the advanced screen.

[Laurent Dinclaux (dreadlox)]

@costales why moving to ufw package which already supports the GRE protocol ? ( sudo ufw allow proto gre )

The issue is in gufw (the Gui for UFW)

[Jamie Strandboge (jdstrand)]

I agree with Laurent - ufw already supports gre, gufw just needs to bubble that up.

[Laurent Dinclaux (dreadlox)]

By the way to be more precise:

- it is a feature request

- gufw displays the GRE rules properly in the GUI

- gufw can delete GRE rules when added by the command line

- gufw cannot add/edit such a rule

[costales (costales)]

       ufw supports several different protocols. The following are valid in any rule and enabled
       when the protocol is not specified:

         tcp
         udp

       The following have certain restrictions and are not enabled when the protocol is not
       specified:

         ah valid without port number
         esp valid without port number
         gre valid without port number
         ipv6 valid for IPv4 addresses and without port number
         igmp valid for IPv4 addresses and without port number

[costales (costales)]

Hi.
I think those protocols don't fit for a simple firewall UI as Gufw... :/
Best regards.