initramfs-rauc-slot: support restoring the backup archive

This change adds an initramfs module to mount the data partition and
restore the backup to the overlay. It is enabled by adding it to the
image-rauc-slot-initramfs recipe.

Signed-off-by: Jan Luebbe <jluebbe@debian.org>

[hfreyther: keep udev out of the dependencies]

recipes-core/images/image-rauc-slot-initramfs.bb

@@ -1,6 +1,6 @@
 DESCRIPTION = "slot initramfs"
 
-PACKAGE_INSTALL = "initramfs-framework-base initramfs-module-debug initramfs-module-rauc-overlay busybox base-passwd ${ROOTFS_BOOTSTRAP_INSTALL}"
+PACKAGE_INSTALL = "initramfs-framework-base initramfs-module-debug initramfs-module-rauc-overlay initramfs-module-rauc-backup busybox base-passwd ${ROOTFS_BOOTSTRAP_INSTALL}"
 
 # Do not pollute the initrd image with rootfs features
 #IMAGE_FEATURES = ""

recipes-core/initrdscripts/initramfs-rauc-slot.bb

@@ -2,12 +2,14 @@ SUMMARY = "Modular initramfs system components for RAUC"
 LICENSE = "MIT"
 LIC_FILES_CHKSUM = "file://${COREBASE}/meta/COPYING.MIT;md5=3da9cfbcb788c80a0384361b4de20420"
 
-PR = "r1"
+PR = "r2"
 
 inherit allarch
 
 SRC_URI = "file://overlay \
-           file://rescue"
+	   file://rescue \
+	   file://mount_data \
+	   file://restore_backup"
 
 do_install() {
     install -d ${D}/init.d
@@ -17,10 +19,15 @@ do_install() {
 
     # rescue
     install -m 0755 ${WORKDIR}/rescue ${D}/init.d/10-rescue
+
+    # backup
+    install -m 0755 ${WORKDIR}/mount_data ${D}/init.d/25-mount_data
+    install -m 0755 ${WORKDIR}/restore_backup ${D}/init.d/26-restore_backup
 }
 
 PACKAGES = "initramfs-module-rauc-overlay \
-            initramfs-module-rauc-rescue"
+	    initramfs-module-rauc-rescue \
+	    initramfs-module-rauc-backup"
 
 SUMMARY_initramfs-module-rauc-overlay = "initramfs support for overlayfs (ubifs&squashfs)"
 RDEPENDS_initramfs-module-rauc-overlay = "initramfs-framework-base"
@@ -29,3 +36,7 @@ FILES_initramfs-module-rauc-overlay = "/init.d/20-overlay"
 SUMMARY_initramfs-module-rauc-rescue = "initramfs rescue mode support"
 RDEPENDS_initramfs-module-rauc-rescue = "initramfs-framework-base"
 FILES_initramfs-module-rauc-rescue = "/init.d/10-rescue"
+
+SUMMARY_initramfs-module-rauc-backup = "initramfs backup restore support"
+RDEPENDS_initramfs-module-rauc-backup = "initramfs-module-rauc-overlay"
+FILES_initramfs-module-rauc-backup = "/init.d/25-mount_data /init.d/26-restore_backup"

recipes-core/initrdscripts/initramfs-rauc-slot/restore_backup

@@ -0,0 +1,31 @@
+#!/bin/sh
+
+BACKUP_FILE=/rootfs/data/sysmocom-backup.tar
+
+restore_backup_enabled() {
+	if [ ! -e "$BACKUP_FILE" ] ; then
+		info "The backup file '$BACKUP_FILE' does not exist, skipping restore..."
+		return 1
+	fi
+
+	return 0
+}
+
+restore_backup_extract() {
+	# List the files and check if grep hits something
+	SEARCH=`tar -tvf $1 | grep $2`
+	RES=$?
+	if [ $RES = 0 ]; then
+		tar -C /rootfs/tmp/ -xvf $1 $2
+		cp -a /rootfs/tmp/content/* /rootfs/
+		rm -rf /rootfs/tmp/content
+	else
+		echo "Directory '$2' is not in backup '$1'."
+	fi
+}
+
+restore_backup_run() {
+	info "Extracting files from the backup '$BACKUP_FILE'"
+	restore_backup_extract $BACKUP_FILE content/etc || fatal "Failed!"
+	restore_backup_extract $BACKUP_FILE content/var/lib/osmocom || fatal "Failed!"
+}

recipes-core/initrdscripts/initramfs-rauc-slot/sysmobts-v2/mount_data

@@ -0,0 +1,11 @@
+#!/bin/sh
+
+mount_data_enabled() {
+	return 0
+}
+
+mount_data_run() {
+	info "Mounting data..."
+	mkdir -p /rootfs/data
+	mount -t ubifs ubi0:data /rootfs/data
+}

recipes-core/initrdscripts/initramfs-rauc-slot/sysmocom-bsc/mount_data

@@ -0,0 +1,11 @@
+#!/bin/sh
+
+mount_data_enabled() {
+	return 0
+}
+
+mount_data_run() {
+	info "Mounting data..."
+	mkdir -p /rootfs/data
+	mount -t ext4 /dev/sda4 /rootfs/data
+}

recipes-core/initrdscripts/initramfs-rauc-slot/sysmocom-odu/mount_data

@@ -0,0 +1,11 @@
+#!/bin/sh
+
+mount_data_enabled() {
+	return 0
+}
+
+mount_data_run() {
+	info "Mounting data..."
+	mkdir -p /rootfs/data
+	mount -t ubifs ubi0:data /rootfs/data
+}