[FR]: SoftEtherVPN stable edition about fail2ban HOT 1 OPEN

Don't understand why you need this new issue or why the discussion cannot continue further in #3669, but OK.

I believe it's necessary to add support for the stable edition.

I though that I detailed wrote about the necessity and sense of this work.
But OK, just note that the time I spent for that minor stuff could be invested in further development of fail2ban.
Sad that a lot of trivialities like this hinder me to do another work (here and in other OSS projects).

config/filter.d/softethervpn_se.conf

I already wrote before:
many filters of the same thing are not welcome here, so in best case the version should be parametrized somehow.

The reason is - if one follows this strategy, in few years we'd have thousand filters (and jails) and nobody has overall control over it,

Here, '_se' indicates the Stable edition.

I don't like the naming too, because what is stable today becomes obsolete tomorrow.

As for parametrized filter, something like that could work (here logformat is the parameter controlling that):

[INCLUDES]
before = common.conf

[Definition]
failregex = <<logformat>/failregex>

logformat = singleline

[singleline]
failregex = ^<__prefix_line>(?:(?:\([\d\-]+ [\d:.]+\) )?<SECURITY_LOG>: )?Connection "[^"]+": User authentication failed. The user name that has been provided was "<F-USER>(?:[^"]+|.+)</F-USER>", from <ADDR>\.$

[multiline]
failregex = ^\s*The <F-NOFAIL>connection</F-NOFAIL> "<F-MLFID>CID-\d+</F-MLFID>" \(IP address: <ADDR>,
            ^\s*Connection "<F-MLFID>CID-\d+</F-MLFID>": User authentication failed\. The user name that has been provided was "<F-USER>[^"]+</F-USER>"

from fail2ban.