blacklistd(8) on FreeBSD
The text b6bf535446a6, as FreeBSD 12.1-RELEASE, FreeBSD 12.0-RELEASE shipped it.
block and release ports on demand to avoid DoS abuse
Flags it lists
-
-C -
-D -
-P -
-R -
-c -
-d -
-f -
-r -
-s -
-t -
-v