Don't use ssh-keygen -A for init scripts

We are running into race conditions with glean, which ssh-keygen -A is
not handling properly.  So, create a new script to first check if the
file exists, then use 'yes' to disable overwriting of existing files.

Change-Id: Ie82e1e3f832fcc8f32c7e1335c5f0ee16d36f9a8
Signed-off-by: Paul Belanger <pabelanger@redhat.com>

elements/runtime-ssh-host-keys/element-deps

@@ -1 +1,2 @@
 dib-init-system
+install-static

elements/runtime-ssh-host-keys/init-scripts/systemd/ssh-keygen.service

@@ -2,19 +2,8 @@
 Description=OpenSSH Server Key Generation
 Before=ssh.service
 
-ConditionPathExists=|!/etc/ssh/ssh_host_key
-ConditionPathExists=|!/etc/ssh/ssh_host_key.pub
-ConditionPathExists=|!/etc/ssh/ssh_host_rsa_key
-ConditionPathExists=|!/etc/ssh/ssh_host_rsa_key.pub
-ConditionPathExists=|!/etc/ssh/ssh_host_dsa_key
-ConditionPathExists=|!/etc/ssh/ssh_host_dsa_key.pub
-ConditionPathExists=|!/etc/ssh/ssh_host_ecdsa_key
-ConditionPathExists=|!/etc/ssh/ssh_host_ecdsa_key.pub
-ConditionPathExists=|!/etc/ssh/ssh_host_ed25519_key
-ConditionPathExists=|!/etc/ssh/ssh_host_ed25519_key.pub
-
 [Service]
-ExecStart=/usr/bin/ssh-keygen -A
+ExecStart=/usr/local/sbin/runtime-ssh-host-keys.sh
 Type=oneshot
 RemainAfterExit=yes
 

elements/runtime-ssh-host-keys/init-scripts/upstart/ssh-keygen.conf

@@ -5,4 +5,4 @@ console output
 
 task
 
-exec /usr/bin/ssh-keygen -A
+exec /usr/local/sbin/runtime-ssh-host-keys.sh

elements/runtime-ssh-host-keys/static/usr/local/sbin/runtime-ssh-host-keys.sh

@@ -0,0 +1,29 @@
+#!/bin/bash
+# Copyright 2016 Red Hat, Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+# dib-lint: disable=dibdebugtrace
+
+set -exu
+set -o pipefail
+
+# We are running into race conditions with glean, which ssh-keygen -A is
+# not handling properly.  So, create a new script to first check if the
+# file exists, then use 'yes' to disable overwriting of existing files.
+
+for key in dsa ecdsa ed25519 rsa; do
+    FILE=/etc/ssh/ssh_host_${key}_key
+    if ! [ -e $FILE ]; then
+        /usr/bin/yes n | /usr/bin/ssh-keygen -f $FILE -N '' -t $key
+    fi
+done