[OE-core] [PATCH] rootfs-postcommands.bbclass: break up read_only_rootfs_hook

[Nick Rosbrook]

The function read_only_rootfs_hook makes changes to ssh, dropbear,
fstab, and sysvinit configurations. Replace this function with
four new functions for each component so that they can be removed
from postprocess independently of each other.

Signed-off-by: Nick Rosbrook <rosbrookn at ainfosec.com>
---
 meta/classes/rootfs-postcommands.bbclass | 22 +++++++++++++++++-----
 1 file changed, 17 insertions(+), 5 deletions(-)

diff --git a/meta/classes/rootfs-postcommands.bbclass b/meta/classes/rootfs-postcommands.bbclass
index bde58ad6cd..110f67e40d 100644
--- a/meta/classes/rootfs-postcommands.bbclass
+++ b/meta/classes/rootfs-postcommands.bbclass
@@ -15,7 +15,16 @@ ROOTFS_POSTPROCESS_COMMAND += '${@bb.utils.contains_any("IMAGE_FEATURES", [ 'deb
 ROOTFS_POSTPROCESS_COMMAND += "rootfs_update_timestamp ; "
 
 # Tweak the mount options for rootfs in /etc/fstab if read-only-rootfs is enabled
-ROOTFS_POSTPROCESS_COMMAND += '${@bb.utils.contains("IMAGE_FEATURES", "read-only-rootfs", "read_only_rootfs_hook; ", "",d)}'
+ROOTFS_POSTPROCESS_COMMAND += '${@bb.utils.contains("IMAGE_FEATURES", "read-only-rootfs", "read_only_fstab; ", "",d)}'
+
+# Change the default sshd_config if read-only-rootfs is enabled
+ROOTFS_POSTPROCESS_COMMAND += '${@bb.utils.contains("IMAGE_FEATURES", "read-only-rootfs", "read_only_sshd; ", "",d)}'
+
+# Change the default key locations for dropbear if read-only-rootfs is enabled
+ROOTFS_POSTPROCESS_COMMAND += '${@bb.utils.contains("IMAGE_FEATURES", "read-only-rootfs", "read_only_dropbear; ", "",d)}'
+
+# Tweaks for sysvinit if read-only-rootfs is enabled
+ROOTFS_POSTPROCESS_COMMAND += '${@bb.utils.contains("IMAGE_FEATURES", "read-only-rootfs", "read_only_sysvinit; ", "",d)}'
 
 # We also need to do the same for the kernel boot parameters,
 # otherwise kernel or initramfs end up mounting the rootfs read/write
@@ -86,15 +95,14 @@ systemd_create_users () {
 	done
 }
 
-#
-# A hook function to support read-only-rootfs IMAGE_FEATURES
-#
-read_only_rootfs_hook () {
+read_only_fstab () {
 	# Tweak the mount option and fs_passno for rootfs in fstab
 	if [ -f ${IMAGE_ROOTFS}/etc/fstab ]; then
 		sed -i -e '/^[#[:space:]]*\/dev\/root/{s/defaults/ro/;s/\([[:space:]]*[[:digit:]]\)\([[:space:]]*\)[[:digit:]]$/\1\20/}' ${IMAGE_ROOTFS}/etc/fstab
 	fi
+}
 
+read_only_sshd () {
 	# If we're using openssh and the /etc/ssh directory has no pre-generated keys,
 	# we should configure openssh to use the configuration file /etc/ssh/sshd_config_readonly
 	# and the keys under /var/run/ssh.
@@ -107,14 +115,18 @@ read_only_rootfs_hook () {
 			echo "SSHD_OPTS='-f /etc/ssh/sshd_config_readonly'" >> ${IMAGE_ROOTFS}/etc/default/ssh
 		fi
 	fi
+}
 
+read_only_dropbear () {
 	# Also tweak the key location for dropbear in the same way.
 	if [ -d ${IMAGE_ROOTFS}/etc/dropbear ]; then
 		if [ ! -e ${IMAGE_ROOTFS}/etc/dropbear/dropbear_rsa_host_key ]; then
 			echo "DROPBEAR_RSAKEY_DIR=/var/lib/dropbear" >> ${IMAGE_ROOTFS}/etc/default/dropbear
 		fi
 	fi
+}
 
+read_only_sysvinit () {
 	if ${@bb.utils.contains("DISTRO_FEATURES", "sysvinit", "true", "false", d)}; then
 		# Change the value of ROOTFS_READ_ONLY in /etc/default/rcS to yes
 		if [ -e ${IMAGE_ROOTFS}/etc/default/rcS ]; then
-- 
2.17.1