/usr/share/tripleo-image-elements/devstack/install.d/99-ssh is in python-tripleo-image-elements 0.7.1-1.
This file is owned by root:root, with mode 0o755.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 | #!/bin/bash
# Regenerate host keys now. XXX: Really should be a cloud-init task, should get
# that working.
set -e
set -o xtrace
dpkg-reconfigure openssh-server
|