openharmony-standard-image-tests: Fix ptest ssh timeout in QEMU

SSH host keys are generated by sshdgenkeys.service, which is started by socket
activation on first SSH connection. On QEMU this can take a very long time, even
more than the 300 seconds that is the default timeout when running SSH commands
testimage recipes.

Pre-generated SSH host keys prevents this.

Note, this is only done in the -test image, as it is insecure and should never
be done in images used for other purposes!

Signed-off-by: Esben Haabendal <esben@geanix.com>

conf/distro/oniro-openharmony-linux.conf

@@ -40,6 +40,9 @@ INHERIT += "uninative"
 # instead.
 HOSTTOOLS += "ip ping ps scp ssh stty"
 
+# Yocto does not have ssh-keygen-native, so we need to use ssh-keygen from host
+HOSTTOOLS += "ssh-keygen"
+
 # Default to enabling serial debug console on RaspberryPi
 # Placed here to amend the machine config living in meta-raspberrypi
 ENABLE_UART:raspberrypi4-64 ?= "1"

recipes-openharmony/images/openharmony-standard-image-tests.bb

@@ -25,3 +25,13 @@ IMAGE_INSTALL += "ptest-runner"
 
 # install OpenHarmony components and ptests
 IMAGE_INSTALL += "openharmony-standard-ptest"
+
+# Pre-generate SSH host keys for quick first time SSH connection
+ROOTFS_POSTPROCESS_COMMAND += "ssh_host_key_gen;"
+SSH_HOST_KEY_TYPES="rsa ecdsa ed25519"
+ssh_host_key_gen() {
+    mkdir -p "${IMAGE_ROOTFS}${sysconfdir}/ssh/"
+    for type in ${SSH_HOST_KEY_TYPES} ; do
+        ssh-keygen -f "${IMAGE_ROOTFS}${sysconfdir}/ssh/ssh_host_"$type"_key" -N '' -t $type
+    done
+}