skey(1) on OpenBSD
The text 9d2648af6ab3, as OpenBSD 3.3, OpenBSD 3.2, OpenBSD 3.1, OpenBSD 3.0 shipped it.
respond to an OTP challenge
Flags it lists
-
-md4 -
-md5 -
-n -
-p -
-rmd160 -
-sha1 -
-x