Issue 2487 - Introduce fail2ban module

modules/fail2ban/manifests/filter.pp

+# == Type: fail2ban::filter
+#
+# Manage filter information and files for any custom filter we create

[mathias, 2016/11/24 16:08:48]

Please use un-personalized text in documentation, i.e. "filter created" vs
"filter we create" - or just "filter". And full sentences (including periods)
are appreciated as well ;-)

[f.lopez, 2016/11/25 15:13:49]

Acknowledged.

+#
+# == Parameters:
+#
+# [*failregex*]
+#   The regular expressions used to detect break-in attempts, password failures, etc.
+#   One per line

[mathias, 2016/11/24 16:08:48]

A bit too specific. Something like "The regular expression applied by the
filter." is more than enough. And what do you mean by "One per line"?

[f.lopez, 2016/11/25 15:13:48]

Acknowledged.

+#
+# === Examples:
+#
+#   filters => {
+#     'wordpress' => {
+#       failregex => [
+#         '^<HOST>.*\"WordPress\/.*',
+#       ],
+#     }
+#   },

[mathias, 2016/11/24 16:08:48]

The example is not valid Puppet code, a snippet at best, but even then not
matching the fail2ban::filter type.

[f.lopez, 2016/11/25 15:13:48]

Acknowledged.

+define fail2ban::filter (
+  $failregex = undef,
+  $ensure = 'present',

[mathias, 2016/11/24 16:08:48]

The $ensure parameter is not documented yet.

[f.lopez, 2016/11/25 15:13:49]

Acknowledged.

+) {
+
+  include fail2ban
+  include stdlib
+
+  if $failregex != undef {

[mathias, 2016/11/24 16:08:48]

This condition does not make much sense in this context. What if $ensure =
'absent'? Nothing will happen. I think the better approach would be to fail() if
$ensure = 'present' and $failregex == undef, and have the resource definition
below the conditional statement.

[f.lopez, 2016/11/25 15:13:49]

There can be cases where an already existing filter is in the folder so one
might want to remove it.

+    file {"/etc/fail2ban/filter.d/$title.conf":
+      ensure => $ensure,
+      content => template("fail2ban/filter.erb"),
+      group => 'root',
+      mode => '0644',
+      owner => 'root',
+      require => Package['fail2ban'],
+      notify => Service['fail2ban'],
+    }
+  }
+}