Merge ~andrea-frittoli/cirros:bug_1564948 into cirros:0.3

[Andrea Frittoli]

This branch includes one commit (cherry-picked from master), which fixes https://launchpad.net/bugs/1564948.

The content of the commit is http://bazaar.launchpad.net/~cirros-dev/cirros/trunk/revision/366, rebased on top of branch 3.0, with the only conflict being the removal of dropbear-init-generate-keys.patch from patches-buildroot/series.

A Tempest test for hard reboot in some cases hits the case where the host key is empty, as the file system flush does not happen quickly enough. This triggers bugs/1564948, i.e. the ssh daemon does not start at all, and the Tempest test fails with "connection refused", which is misleading.

Using a new release of CirrOS which includes this branch would solve the problem.

[Scott Moser (smoser)]

some conversationin irc.. andreaf foundn this not to work, i suggest trying on top of this
http://paste.ubuntu.com/23905445/

Unmerged commits

093f907... by Hugh Saunders <email address hidden> on 2016-06-29

Ensure dropbear will start even if keyfiles are empty.

Copy the dropbear init script inside cirros rather than
patching it. That makes this easier to read.

LP: #1564948

diff --git a/src/etc/init.d/S50dropbear b/src/etc/init.d/S50dropbear
 new file mode 100755
index 0000000..1ce463f
--- /dev/null
+++ b/src/etc/init.d/S50dropbear
@@ -0,0 +1,68 @@
+#!/bin/sh
+#
+# Starts dropbear sshd.
+#
+
+echo "Top of dropbear init script"
+
+# Allow a few customizations from a config file
+test -r /etc/default/dropbear && . /etc/default/dropbear
+
+start() {
+	DROPBEAR_ARGS="$DROPBEAR_ARGS -R"
+
+	echo -n "Starting dropbear sshd: "
+	umask 077
+	# Ensure host keys are changed when instance ID changes
+	cirros-per instance remove-dropbear-host-keys -- rm -rf /etc/dropbear
+	
+	# Make sure dropbear directory exists
+	if [ ! -d /etc/dropbear ]; then
+		mkdir -p /etc/dropbear
+	fi
+
+	# Regenerate invalid or missing keys
+	local ktype file
+	for ktype in rsa dss ecdsa; do
+		file="/etc/dropbear/dropbear_${ktype}_host_key"
+		# -f = input file, -y = validate and print pubkey info
+		if ! dropbearkey -f "$file" -y &>/dev/null; then
+			if [ -e "$file" ]; then
+				echo "Removing invalid key: $file"
+				rm -f "$file"
+			fi
+			# -t = type (dss, rsa, ecdsa), -f = output file
+			dropbearkey -t "$ktype" -f "$file" >/dev/null 2>&1 ||
+		echo "WARN: generating key of type $ktype failed!"
+		fi
+	done
+	start-stop-daemon -S -q -p /var/run/dropbear.pid \
+		--exec /usr/sbin/dropbear -- $DROPBEAR_ARGS
+	[ $? = 0 ] && echo "OK" || echo "FAIL"
+}
+stop() {
+	echo -n "Stopping dropbear sshd: "
+	start-stop-daemon -K -q -p /var/run/dropbear.pid
+	[ $? = 0 ] && echo "OK" || echo "FAIL"
+}
+restart() {
+	stop
+	start
+}
+
+case "$1" in
+  start)
+  	start
+	;;
+  stop)
+  	stop
+	;;
+  restart|reload)
+  	restart
+	;;
+  *)
+	echo "Usage: $0 {start|stop|restart}"
+	exit 1
+esac
+
+exit $?