[Pkg-exim4-users] [m40636067 at gmail.com: Protect against brute-force: how to use BADAUTH_LIMIT]

[Andreas Metzler]

----- Forwarded message from Brian Wengel <m40636067 at gmail.com> -----
Date: Tue, 7 Jan 2020 00:31:20 +0100
From: Brian Wengel <m40636067 at gmail.com>
Subject: Protect against brute-force: how to use BADAUTH_LIMIT
Message-ID: <CADcL3SCSjupaB09giJNgP+ETVNUb2hdKv4gSoUVQ-yLJQE0-sA at mail.gmail.com>

I've read this thread:
https://lists.exim.org/lurker/message/20120709.015548.eb9d2ba2.en.html

This is how my "/etc/exim4/conf.d/acl/00_exim4-config_header" looks like:
----------------------------------------
BADAUTH_LIMIT = 5 / 2h

acl_smtp_connect = check_connection
acl_smtp_quit = check_quit
acl_smtp_notquit = check_notquit

begin acl

check_connection:
 drop message = Too many failed authentication attempts
 ratelimit = BADAUTH_LIMIT / noupdate / badauth:$sender_host_address

check_quit:
 accept condition = ${if eq{$authentication_failed}{1}}
 ratelimit = BADAUTH_LIMIT / badauth:$sender_host_address

check_notquit:
 accept condition = ${if eq{$authentication_failed}{1}}
 ratelimit = BADAUTH_LIMIT / badauth:$sender_host_address
----------------------------------------

Now when I make a telnet connection to the server I get this error:

# telnet 127.0.0.1 25
Trying 127.0.0.1...
Connected to 127.0.0.1.
Escape character is '^]'.
550 Administrative prohibition
Connection closed by foreign host.
What did I do wrong?

Secondly, where could I have found information about BADAUTH_LIMIT etc?
Been searching the Debian readme and the upstream documentation file, but
couldn't find any.

----- End forwarded message -----
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