Allow ICMP rules

[phoenix1589]

Currently only TCP/UDP can be specified in firewall rules. Would it be possible to extend this to include ICMP as a protocol that can be configured?

[capnspacehook]

It's definitely possible, the config format would likely have to be updated as I'm sure you'd want the ability to specify what ICMP messages would be allowed or denied right?

[sammcj]

Does the current configuration block all ICMP by default?

*Edit I just tested this and indeed all ICMP is blocked, is there at least a way to allow it by default?

I tried adding - proto: icmp but that resulted in a mild explosion:

{"level":"error","time":"2023-08-21T09:03:40.977906129Z","msg":"error creating rules","container.id":"bfc355a8cc43","container.name":"borgmatic","error":"error parsing rules: invalid protocol \"icmp\"","stacktrace":"github.com/capnspacehook/whalewall.(*RuleManager).createRules\n\tgithub.com/capnspacehook/whalewall/create.go:63\ngithub.com/capnspacehook/whalewall.(*RuleManager).Start.func1\n\tgithub.com/capnspacehook/whalewall/manager.go:118"}