skey(1) on OpenBSD
The text 30098b4cc4a3, as OpenBSD 5.5, OpenBSD 5.4, OpenBSD 5.3 shipped it.
respond to an OTP challenge
Flags it lists
-
-md4 -
-md5 -
-n -
-p -
-rmd160 -
-sha1 -
-x