The original blacklist library supported two notification types:
- failed auth attempt, which incremented the failed login count
by one for the remote address
- successful auth attempt, which reset the failed login count
to zero for that remote address
When the failed login count reached the limit in the configuration
file, the remote address would be blocked by a packet filter.
This patch implements a new notification type, "abusive behavior",
and accepts, but does not act on an additional type, "bad username".
It is envisioned that a system administrator will configure a small
list of "known bad usernames" that should be blocked immediately.
Reviewed by: emaste
MFC after: 3 days
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D10604
This import includes The basic blacklist library and utility programs,
to add a system-wide packet filtering notification mechanism to
FreeBSD.
The rational behind the daemon was given by Christos Zoulas in a
presentation at vBSDcon 2015: https://youtu.be/fuuf8G28mjs
Reviewed by: rpaulo
Approved by: rpaulo
Obtained from: NetBSD
Relnotes: YES
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D5912