Merge branch 'master' into nobash

21 files changed, 265 insertions, 119 deletions

diff --git a/builder/build-initramfs.sh b/builder/build-initramfs.sh
index b8599e43..eb8e99b7 100755
--- a/builder/build-initramfs.sh
+++ b/builder/build-initramfs.sh
@@ -44,7 +44,7 @@ if [ ! -e "$_repo_dir" ]; then
         [ "$mod" = "xmount" ]                  && depth_arg+=("2015-11-05")
         [ "$mod" = "kernel-qcow2-linux" ]      && depth_arg+=("2019-08-25")
         [ "$mod" = "kernel-qcow2-util-linux" ] && depth_arg+=("2019-08-15")
-        git clone -n --no-tags "${depth_arg[@]}" --branch "$branch" "$url" "$path"
+        git clone --no-checkout "${depth_arg[@]}" --branch "$branch" "$url" "$path"
         pushd "$path"
         git checkout "$commit"
         popd
@@ -70,7 +70,7 @@ full_cleanup='no'
 use_systemd_in_initramfs='no'
 
 print_help_message() {
-				echo "help"
+				echo "TODO"
 }
 
 parse_command_line() {
diff --git a/builder/modules.d/conf-tgz/hooks/fetch-config-tgz.sh b/builder/modules.d/conf-tgz/hooks/fetch-config-tgz.sh
index 89852974..26e705b2 100755
--- a/builder/modules.d/conf-tgz/hooks/fetch-config-tgz.sh
+++ b/builder/modules.d/conf-tgz/hooks/fetch-config-tgz.sh
@@ -3,13 +3,12 @@
 
 type emergency_shell >/dev/null 2>&1 || source /lib/dracut-lib.sh
 
-
-slx_server="$(getarg slxsrv=)"
-slx_server_base="$(getarg slxbase=)"
+. /etc/openslx
 
 if [ -z "$SLX_NO_CONFIG_TGZ" ]; then
-	# build config.tgz url
-	conftgz_url="http://${slx_server#@}/${slx_server_base}/config.tgz"
+	# build config.tgz url from SLX_KCL_SERVERS and SLX_BASE_PATH
+	# both are written to /etc/openslx by dnbd3-rootfs's fetch-config.sh script
+	conftgz_url="http://${SLX_KCL_SERVERS}/${SLX_BASE_PATH}/config.tgz"
 
 	# check if system's uuid was set
 	if [ -s "/run/system-uuid" ]; then
@@ -22,8 +21,7 @@ if [ -z "$SLX_NO_CONFIG_TGZ" ]; then
 	slx-tools download_retry -s "${conftgz_url}" > "/etc/config.tgz"
 
 	if [[ ! -s "/etc/config.tgz" ]]; then
-		warn \
-			"Downloading 'config.tgz' from '${slx_server}' failed with: $return_code"
-		# TODO handle error
+		warn "Failed to download '${conftgz_url}'!"
 	fi
 fi
+:
diff --git a/builder/modules.d/conf-tgz/hooks/unpack-config-tgz.sh b/builder/modules.d/conf-tgz/hooks/unpack-config-tgz.sh
index a0da0cd3..71b3ca1e 100755
--- a/builder/modules.d/conf-tgz/hooks/unpack-config-tgz.sh
+++ b/builder/modules.d/conf-tgz/hooks/unpack-config-tgz.sh
@@ -14,28 +14,36 @@ tarcopy() {
 	cd - &>/dev/null
 }
 
-# this module unpacks the config.tgz
-temporary_extract_directory="$(mktemp -d)"
-	if [[ -e "/etc/config.tgz" ]]; then
-		tar --extract --preserve-permissions \
-			--file="/etc/config.tgz" \
-			--directory="$temporary_extract_directory"
+unpack_config_tgz() {
+	local config_tgz="/etc/config.tgz"
+	[ -e "$config_tgz" ] || return 1
+	local extract_dir="$(mktemp -d)"
+	tar --extract --preserve-permissions \
+		--file="/etc/config.tgz" \
+		--directory="$extract_dir"
+	if [ "$?" -ne 0 ]; then
+		warn "Failed to extract '$config_tgz' to '$extract_dir'."
+		return 1
 	fi
-	warn "Failed to extract '/etc/config.tgz' to '$temporary_extract_directory'."
-	warn "$exceptions_last_traceback"
-# extracted to temporary directory, now check for SLX_LOCAL_CONFIGURATION
-
-source "/etc/openslx"
-if [[ -n "$SLX_LOCAL_CONFIGURATION" ]]; then
-	if [[ ! -d "${temporary_extract_directory}/openslx-configs/${SLX_LOCAL_CONFIGURATION}" ]]; then
-		warn "SLX_LOCAL_CONFIGURATION is set but no corresponding folder found in '/etc/config.tgz'. Ignoring..."
-	else
-		tarcopy "${temporary_extract_directory}/openslx-configs/${SLX_LOCAL_CONFIGURATION}" "${temporary_extract_directory}"
+	# check SLX_LOCAL_CONFIGURATION
+	source "/etc/openslx"
+	if [ -n "$SLX_LOCAL_CONFIGURATION" ]; then
+		if [ ! -d "${extract_dir}/openslx-configs/${SLX_LOCAL_CONFIGURATION}" ]; then
+			warn "Ignoring missing SLX_LOCAL_CONFIGURATION in '/etc/config.tgz'."
+		else
+			tarcopy \
+				"${extract_dir}/openslx-configs/${SLX_LOCAL_CONFIGURATION}" \
+				"${extract_dir}"
+		fi
 	fi
-fi
-	# purge openslx-configs/
-	rm -rf "${temporary_extract_directory}/openslx-configs"
-	tarcopy "${temporary_extract_directory}" "$NEWROOT"
+	# always purge openslx-configs/
+	rm -rf "${extract_dir}/openslx-configs"
 
+	# finally copy the rest into stage4
+	if ! tarcopy "${extract_dir}" "$NEWROOT"; then
+		warn "'tarcopy' from '$extract_dir' to '$NEWROOT' failed."
+	fi
+}
 
-	# TODO error handling
+unpack_config_tgz
+:
diff --git a/builder/modules.d/dnbd3-rootfs/hooks/fetch-config.sh b/builder/modules.d/dnbd3-rootfs/hooks/fetch-config.sh
index a11332a7..2fa1c78c 100755
--- a/builder/modules.d/dnbd3-rootfs/hooks/fetch-config.sh
+++ b/builder/modules.d/dnbd3-rootfs/hooks/fetch-config.sh
@@ -7,6 +7,20 @@ type emergency_shell >/dev/null 2>&1 || source /lib/dracut-lib.sh
 slx_server="$(getarg slxsrv=)"
 slx_server_base="$(getarg slxbase=)"
 
+# if no slxsrv was specified, use the server the kernel was
+# downloaded from as fallback. Mostly for legacy PXE boot.
+if [ -z "$slx_server" ]; then
+    slx_server="$(getarg BOOT_IMAGE= | awk -F[/:] '{print $4}')"
+fi
+if [ -z "$slx_server" ]; then
+    # use tftp server from ip parameter
+    slx_server="$(getarg ip= | awk -F: '{print $2}' )"
+fi
+if [ -z "$slx_server" ]; then
+    # we have a problem :/
+    emergency_shell "Failed to determine SLX server to fetch config from."
+fi
+
 # build config_url
 config_url="http://${slx_server#@}/${slx_server_base}/config"
 
diff --git a/builder/modules.d/dnbd3-rootfs/hooks/prepare-root-partition.sh b/builder/modules.d/dnbd3-rootfs/hooks/prepare-root-partition.sh
index 6a6b64f2..86cc60ad 100755
--- a/builder/modules.d/dnbd3-rootfs/hooks/prepare-root-partition.sh
+++ b/builder/modules.d/dnbd3-rootfs/hooks/prepare-root-partition.sh
@@ -42,7 +42,13 @@ container_unpack_losetup() {
 }
 # endregion
 
-(
+# region connect dnbd3 image
+# if not specified, use the default name for the bwlp stage4 image
+if [ -z "$SLX_DNBD3_IMAGE" ]; then
+    SLX_DNBD3_IMAGE="stage4/bwlp/maxilinux-$(uname -r)"
+    echo "SLX_DNBD3_IMAGE='$SLX_DNBD3_IMAGE'" >> /etc/openslx
+fi
+
 IFS=", "
 for host in ${SLX_DNBD3_SERVERS} FAIL; do
     if [ "$host" = "FAIL" ]; then
@@ -59,10 +65,10 @@ for host in ${SLX_DNBD3_SERVERS} FAIL; do
         break
     fi
 done
-)
+
 # endregion
 # region unpack dnbd3 image
-[ -z "$SLX_QCOW_HANDLER" ] && SLX_QCOW_HANDLER="xmount"
+[ -z "$SLX_QCOW_HANDLER" ] && SLX_QCOW_HANDLER="kernel"
 if [ "$SLX_QCOW_HANDLER" = "xmount" ]; then
     read_only_device="$(container_unpack_xmount "$_dnbd3_dev")"
 elif [ "$SLX_QCOW_HANDLER" = "kernel" ]; then
@@ -72,19 +78,19 @@ else
 fi
 
 # Fail fast if unpacking dnbd3 image failed.
-[ -z "$read_only_device" ] && exit 1
+if [ -z "$read_only_device" ]; then
+    emergency_shell "Failed to unpack the qcow2 image!"
+fi
 
 # endregion
 # region find system partition within dnbd3 image
 if [ -z "$SLX_SYSTEM_PARTITION_PREPARATION_SCRIPT" ]; then
     if [ -z "$SLX_SYSTEM_PARTITION_IDENTIFIER" ]; then
-        # if empty use whole device
-        read_only_partition="$read_only_device"
-        true
-    else
-        read_only_partition="$(slx-tools dev_find_partitions \
-            "$read_only_device" "$SLX_SYSTEM_PARTITION_IDENTIFIER")"
+        SLX_SYSTEM_PARTITION_IDENTIFIER="SLX_SYS"
+        echo "SLX_SYSTEM_PARTITION_IDENTIFIER='$SLX_SYSTEM_PARTITION_IDENTIFIER'" >> /etc/openslx
     fi
+    read_only_partition="$(slx-tools dev_find_partitions \
+        "$read_only_device" "$SLX_SYSTEM_PARTITION_IDENTIFIER")"
 else
     eval "$SLX_SYSTEM_PARTITION_PREPARATION_SCRIPT"
 fi
diff --git a/builder/modules.d/slx-addons/module-setup.sh b/builder/modules.d/slx-addons/module-setup.sh
index 296b3fe4..d75b38ad 100755
--- a/builder/modules.d/slx-addons/module-setup.sh
+++ b/builder/modules.d/slx-addons/module-setup.sh
@@ -9,4 +9,6 @@ depends() {
 }
 install() {
 	inst_hook pre-pivot 30 "$moddir/scripts/setup-addons.sh"
+	inst "${moddir}/services/ldconfig.service" \
+		"/opt/openslx/services/ldconfig.service"
 }
diff --git a/builder/modules.d/slx-addons/scripts/setup-addons.sh b/builder/modules.d/slx-addons/scripts/setup-addons.sh
index 94c2c444..c155a5a5 100644
--- a/builder/modules.d/slx-addons/scripts/setup-addons.sh
+++ b/builder/modules.d/slx-addons/scripts/setup-addons.sh
@@ -33,44 +33,40 @@ if [ ! -d "$NEWROOT/opt/openslx/addons" ]; then
 	return 0
 fi
 
-setup_addons() {
-	local ADDONS_DIR="$NEWROOT/opt/openslx/addons/"
-	cd "$ADDONS_DIR" || return 1
-	for ADDON in *; do
-		if ! setup_addon "$ADDON"; then
-			info "Failed to setup $ADDON"
-		fi
-	done
+# This just activates the ldconfig service to run during the sysinit target
+# Since addons are likely to install libs, this is necessary to garantee
+# that the live system "sees" the libraries.
+activate_stage4_ldconfig() {
+	local service_path="/opt/openslx/services/ldconfig.service"
+	[ -e "$service_path" ] || return 1
+	local target_dir="${NEWROOT}/etc/systemd/system/sysinit.target.wants"
+	mkdir -p "$target_dir"
+	cp -f "$service_path" "${NEWROOT}/etc/systemd/system/${service_path##*/}"
+	ln -sf "../${service_path##*/}" "${target_dir}/${service_path##*/}"
 }
 
 setup_addon() {
-	[ -z "$1" -o ! -d "$ADDONS_DIR/$1" ] && return 1
-	local ADDON="$1"
-	cd "$ADDONS_DIR/$ADDON" || return 1
-
+	if [ ! -d "$1" ]; then
+		warn "Given '$1' not a directory, skipping."
+		return 1
+	fi
+	local addon_dir="$1"
+	cd "$addon_dir"
 	if ! bash addon-required 2>&1 ; then
-		info "'$ADDONS_DIR/$ADDON/addon-required' missing or returned non-zero, skipping..."
+		info "'$addon_dir/addon-required' missing or returned non-zero, skipping..."
 		return 1
 	fi
+	# purge addon-* files
+	rm -f -- addon-*
 
-	for entry in $(find * -not -wholename "addon-*" 2>/dev/null); do
-		if [ -d "$entry" ]; then
-			[ -d "/$entry" ] || mkdir -p "/${entry}"
-			continue
-		fi
-		local dir=${entry%/*}
-		[ -d "$NEWROOT/$dir" ] || mkdir -p "$NEWROOT/$dir"
-		if [ -f "$entry" -a ! -L "$entry" ]; then
-			if [ ! -e "$NEWROOT/${entry}" ] || ! diff -q "$entry" "$NEWROOT/${entry}"; then
-				mv -f -- "$entry" "$NEWROOT/${entry}"
-			fi
-		else
-			# either block dev, char dev or a symlink, just overwrite them "blindly"
-			mv -f -- "$entry" "$NEWROOT/${entry}"
-		fi
+	# move all the files over
+	for entry in $(find * -not -type d 2>/dev/null); do
+		mkdir -p "${NEWROOT}/${entry%/*}"
+		mv -f -- "$entry" "${NEWROOT}/${entry}"
 	done
 
-	# post merge: remove whiteouts from filesystem
+	# post merge: remove files marked as whiteouts
+	# (e.g. they were removed during the addon installation)
 	for WHITEOUT in "$NEWROOT/opt/openslx/etc/"*.whiteout; do
 		[ -e "$WHITEOUT" ] || continue
 		while read line; do
@@ -78,28 +74,29 @@ setup_addon() {
 		done < "$WHITEOUT"
 	done
 
-	# finally update ld.so.cache expected to be under /opt/openslx/etc/<addon_name>.ld.so.cache
-	# NOTE: if we have more than one addon in the future, we need to be extra
- 	# careful with prebuilt ld.caches since they need to match *ALL* addons
-	local ADDON_LD_CACHE="$NEWROOT/opt/openslx/etc/$ADDON.ld.so.cache"
-	if [ ! -e "$ADDON_LD_CACHE" ] || ! mv -f -- "$ADDON_LD_CACHE" "$NEWROOT/etc/ld.so.cache" ; then
-		# Using prebuilt ld cache failed, try hard to find a ldconfig...
-		for LDCONFIG in "$(type -p ldconfig 2>/dev/null)" "${NEWROOT}/sbin/ldconfig.real"; do
-			if [ -x "$LDCONFIG" ] && "$LDCONFIG" -r "$NEWROOT"; then
-				return 0
-			fi
-		done
-		# try with chroot if we have it
-		local CHROOT_PATH="$(type -p chroot 2>/dev/null)"
-		if [ -x "$CHROOT_PATH" ] && "$CHROOT_PATH" "$NEWROOT" ldconfig; then
-			return 0
-		fi
-		# very bad indeed, libraries won't be registered in the cache ...
-		warn "Failed to find 'ldconfig' to rebuild the addon's missing ld.so.cache..."
-		return 1
-	fi
+	cd - &>/dev/null
 }
 
-if ! setup_addons; then
-	warn "Failed to fully setup some addons! They will likely malfunction..."
+active=()
+for addon in "${NEWROOT}/opt/openslx/addons/"*; do
+	if setup_addon "$addon"; then
+		active+=("${addon#${NEWROOT}/opt/openslx/addons/}")
+		info "Activated '$addon' (@ $(date +%s))"
+	fi
+done
+
+# if only one addon was installed, use its pre-generated ld.so.cache
+# if more than one were installed, make sure ldconfig is called in stage4
+if [ "${#active[@]}" -eq 1 ]; then
+	addon_cache="${NEWROOT}/opt/openslx/etc/${active[0]}.ld.so.cache"
+	if [ -e "$addon_cache" ]; then
+		info "Using ld.so.cache of '${active[0]}'."
+		mv -f -- "${NEWROOT}/etc/ld.so.cache"{,.stage4}
+		mv -f -- "$addon_cache" "${NEWROOT}/etc/ld.so.cache"
+	fi
+elif [ "${#active[@]}" -gt 1 ]; then
+	info "Activating ldconfig in stage4 due to multiple loaded addons: ${active[@]}"
+	activate_stage4_ldconfig
 fi
+
+:
diff --git a/builder/modules.d/slx-addons/services/ldconfig.service b/builder/modules.d/slx-addons/services/ldconfig.service
new file mode 100644
index 00000000..b821f743
--- /dev/null
+++ b/builder/modules.d/slx-addons/services/ldconfig.service
@@ -0,0 +1,8 @@
+[Unit]
+Description=Run ldconfig
+Before=graphical.target
+DefaulltDependencies=no
+
+[Service]
+Type=oneshot
+ExecStart=/sbin/ldconfig
diff --git a/builder/modules.d/slx-clock/module-setup.sh b/builder/modules.d/slx-clock/module-setup.sh
index 0c21b032..8fdbbef6 100755
--- a/builder/modules.d/slx-clock/module-setup.sh
+++ b/builder/modules.d/slx-clock/module-setup.sh
@@ -17,4 +17,5 @@ install() {
 	inst_multiple ntpdate /etc/services /usr/share/zoneinfo/Europe/Berlin
 	inst /usr/share/zoneinfo/Europe/Berlin /etc/localtime
 	inst_hook pre-mount 15 "$moddir/scripts/ntp-sync.sh"
+	inst_hook pre-pivot 15 "$moddir/scripts/configure-timesyncd.sh"
 }
diff --git a/builder/modules.d/slx-clock/scripts/configure-timesyncd.sh b/builder/modules.d/slx-clock/scripts/configure-timesyncd.sh
new file mode 100644
index 00000000..af1148eb
--- /dev/null
+++ b/builder/modules.d/slx-clock/scripts/configure-timesyncd.sh
@@ -0,0 +1,12 @@
+#!/bin/bash
+
+. /etc/openslx
+
+if [ -n "$SLX_NTP_SERVER" ]; then
+	tsdir="${NEWROOT}/etc/systemd/timesyncd.conf.d"
+	mkdir -p "$tsdir"
+	(
+	echo "[Time]"
+	echo "NTP=$SLX_NTP_SERVER"
+	) > "${tsdir}/slx-ntp.conf"
+fi
diff --git a/builder/modules.d/slx-dmsetup/module-setup.sh b/builder/modules.d/slx-dmsetup/module-setup.sh
index 68e9b7b4..f7979720 100755
--- a/builder/modules.d/slx-dmsetup/module-setup.sh
+++ b/builder/modules.d/slx-dmsetup/module-setup.sh
@@ -11,14 +11,14 @@ install() {
 	inst_hook pre-pivot 10 "$moddir/scripts/generate-fstab-swap.sh"
 	inst_hook pre-pivot 00 "$moddir/scripts/grow-rootfs.sh"
 	# deliberatly left ext helpers out for now, since we don't really use it.
-	inst_multiple blockdev xxd \
+	inst_multiple blockdev fallocate xxd \
 		mkfs.ext4 resize2fs \
 		xfs_repair xfs_growfs
 }
 installkernel() {
 	# install those modules in case the used kernel does not have them builtin
 	instmods \
-		dm-thin-pool dm-snapshot \
+		dm-thin-pool dm-snapshot dm-zero \
 		dm-crypt crc32c xts \
 		xfs ext4
 }
diff --git a/builder/modules.d/slx-dmsetup/scripts/dmsetup-slx-device b/builder/modules.d/slx-dmsetup/scripts/dmsetup-slx-device
index 1756865e..1f280099 100755
--- a/builder/modules.d/slx-dmsetup/scripts/dmsetup-slx-device
+++ b/builder/modules.d/slx-dmsetup/scripts/dmsetup-slx-device
@@ -24,8 +24,8 @@ exec &> /run/openslx/dmsetup.log
 
 # read-only device to prepare for CoW
 [ -z "$1" ] && emergency_shell "Read-only device was not given!"
-declare -rg read_only_device="$1"
-declare -rg read_only_device_size="$(blockdev --getsz $1)"
+declare -g read_only_device="$1"
+declare -g read_only_device_size="$(blockdev --getsz $1)"
 
 # global array variables storing the configuration of the partitions
 declare -ag linear snapshot thin_snapshot thin_volume
@@ -95,7 +95,7 @@ parse_config() {
 dmsetup_create_noudevsync() {
 	(
 		set -o errexit
-		dmsetup create "$1" --noudevsync --table "$2"
+		printf "%s\n" "$2" | dmsetup create "$1" --noudevsync
 		dmsetup mknodes --noudevsync "$1"
 	)
 	local ret=$?
@@ -129,24 +129,63 @@ create_snapshot() {
 	return 0
 }
 
-# Call this to fallback to a RAMdisk stored under /run/openslx
-# This will call terminate the whole script by calling finish_setup, if successful
+# This function is called if no ID44 partition could be found or anoother kind
+# of critical error occurs during the CoW layer setup. It will combine the
+# the read-only device with a DM zero device to increase its virtual size
+# by half the RAM size. A sparse file of that size will then be created and
+# placed on a dedicated tmpfs.
 ramdisk_fallback() {
 	echo "$0: Falling back to regular dm-snapshot on a RAMdisk."
-	local file="$(mktemp -u -p /run/openslx dnbd_cow.XXX)"
-	local size="$SLX_RAMDISK_SIZE_IN_MB"
-	[ -z "$size" ] && size="$(awk '/MemTotal/ {printf("%d\n", $2 / 2 / 1024 )}' /proc/meminfo)"
-	dd of="$file" seek="$size" bs=1M count=0 &> /dev/null
-	writable_device="$(losetup --show --find "$file")"
-	cow_device_candidate="root"
+
+	# RAM size in kb, note that this is equal to half
+	# of the entire RAM in 512-bytes sectors.
+	local ram_size_in_kb="$(awk '/MemTotal/ {printf("%d\n", $2 )}' /proc/meminfo)"
+
+	#	try to prepare the zero extension device
+	local extended_device="/dev/mapper/${read_only_device##*/}-extended"
+	(
+		set -e
+		lsmod | grep -q dm-zero || modprobe dm-zero
+		dmsetup_create_noudevsync zero "0 $ram_size_in_kb zero"
+		dmsetup_create_noudevsync "${extended_device##*/}" \
+			"0 $read_only_device_size linear $read_only_device 0
+		  $read_only_device_size $ram_size_in_kb linear /dev/mapper/zero 0"
+	)
+	if [ "$?" -eq 0 ]; then
+		read_only_device="$extended_device"
+		read_only_device_size="$(( read_only_device_size + ram_size_in_kb ))"
+	else
+		echo "$0: Failed to setup the fake larger '$read_only_device'."
+		echo "$0: Continuing with its original size."
+	fi
+
+	# prepare dedicated tmpfs mount point
+	local cow_tmpfs="/run/openslx/cow"
+	if ! mkdir -p "$cow_tmpfs"; then
+		cow_tmpfs="${cow_tmpfs}.$$"
+		if ! mkdir -p "$cow_tmpfs"; then
+			# ultimate fallback on regular /run/openslx
+			cow_tmpfs="/run/openslx"
+		fi
+	fi
+	if ! mount -t tmpfs cow-tmpfs -o size="$(( read_only_device_size / 2 ))k" "$cow_tmpfs"; then
+		echo "$0: Failed to mount tmpfs in '$cow_tmpfs' of size '$(( read_only_device_size / 2 ))'."
+	fi
+
+	# create sparse file there
+	local file="$(mktemp -u -p "$cow_tmpfs" dnbd_cow.XXX)"
+	if ! dd of="$file" seek="$(( read_only_device_size / 2 ))" bs=1k count=0 &> /dev/null; then
+		emergency_shell "Failed to allocate CoW file $file."
+	fi
+	declare -rg writable_device="$(losetup --show --find "$file")"
+	local cow_device_candidate="root"
 	while [ -b "/dev/mapper/$cow_device_candidate" ]; do
 		cow_device_candidate="root.$RANDOM"
 	done
 	if [ -z "$writable_device" ] || ! create_snapshot "$cow_device_candidate N"; then
 		emergency_shell "CRITICAL: failed to setup RAMdisk fallback."
-		exit 1
 	fi
-	finish_setup "$cow_device_candidate" "0" "$size"
+	finish_setup "$cow_device_candidate" "0" "$read_only_device_size"
 }
 
 # finish_setup <device> <type> [<size>]
@@ -200,9 +239,15 @@ save_partition_info() {
 . /etc/openslx
 # This is the main variable driving this script
 declare -g writable_device=
+if [ -z "$SLX_WRITABLE_DEVICE_IDENTIFIER" ]; then
+	SLX_WRITABLE_DEVICE_IDENTIFIER=("44" "87f86132-ff94-4987-b250-444444444444")
+	# TODO make scripts reading this variable compatible with list of IDs
+	echo "SLX_WRITABLE_DEVICE_IDENTIFIER='${SLX_WRITABLE_DEVICE_IDENTIFIER[0]}'" >> /etc/openslx
+	echo "SLX_WRITABLE_DEVICE_IDENTIFIERS='${SLX_WRITABLE_DEVICE_IDENTIFIER[@]}'" >> /etc/openslx
+fi
 if [ -n "$SLX_WRITABLE_DEVICE_IDENTIFIER" ]; then
 	# only first one for now TODO create linear devices of all ID44s
-	writable_device="$(slx-tools dev_find_partitions "$SLX_WRITABLE_DEVICE_IDENTIFIER" | head -n 1)"
+	writable_device="$(slx-tools dev_find_partitions "${SLX_WRITABLE_DEVICE_IDENTIFIER[@]}" | head -n 1)"
 fi
 if [ -z "$writable_device" ]; then
 	echo "$0: Could not find writable device with id '$SLX_WRITABLE_DEVICE_IDENTIFIER'."
@@ -319,7 +364,7 @@ create_pool() {
 	# create remaining thin volumes
 	modprobe dm-thin-pool || echo "$0: dm-thin-pool load failed, maybe builtin?"
 	# create temporary metadata device
-	data_block_size=255
+	data_block_size=256
 	# calculate number of sectors needed and check boundaries:
 	metadata_dev_size="$(( 48 * $writable_device_size / $data_block_size / 512 ))"
 	# Min 2MB -> 4096 sectors, max 16GB -> 33554432 sectors
diff --git a/builder/modules.d/slx-network/hooks/activate-bootif-dhcp.sh b/builder/modules.d/slx-network/hooks/activate-bootif-dhcp.sh
index f5345c61..0f4f332f 100644
--- a/builder/modules.d/slx-network/hooks/activate-bootif-dhcp.sh
+++ b/builder/modules.d/slx-network/hooks/activate-bootif-dhcp.sh
@@ -4,7 +4,7 @@
 # within stage4, unless specifically disabled by SLX_STAGE4_DHCP
 
 . /etc/openslx
-[ -n "$SLX_STAGE4_DHCP" ] || exit 0
+[ -n "$SLX_DISABLE_STAGE4_DHCP" ] && exit 0
 
 for script in setup-bootif-network udhcpc-trigger; do
 	if [ -e "${NEWROOT}/opt/openslx/scripts/${script}" ]; then
diff --git a/builder/modules.d/slx-network/scripts/setup-bootif-network.stage3 b/builder/modules.d/slx-network/scripts/setup-bootif-network.stage3
index 53ad8de9..50718894 100755
--- a/builder/modules.d/slx-network/scripts/setup-bootif-network.stage3
+++ b/builder/modules.d/slx-network/scripts/setup-bootif-network.stage3
@@ -88,18 +88,37 @@ if [ -n "$SLX_PXE_CLIENT_IP" ]; then
 		dev "$MAIN_NETIF"
 fi
 
-if [ "$USE_DHCP_UUID" = "yes" ] && [ -s "/run/system-uuid" ]; then
-	UUID="$(cat /run/system-uuid)"
+additional_opts=()
+
+# we need to send the same UID (without '-') as the PXE firmware did, so use the plain
+# one read with dmidecode (and not the one by get-system-uuid).
+if [ "$USE_DHCP_UUID" = "yes" ]; then
+	UID="$(dmidecode -s system-uuid | sed -r 's/^(..)(..)(..)(..)-(..)(..)-(..)(..)-(....)-/00\4\3\2\1\6\5\8\7\9/')"
+	if [ "${#UID}" = 34 ]; then
+		echo "Using SMBIOS UID for DHCP"
+		additional_opts+=("-x" "0x3d:$UID")
+	fi
+fi
+
+if [ -n "$SLX_PXE_CLIENT_IP" ]; then
+	additional_opts+=("-r" "$SLX_PXE_CLIENT_IP")
 fi
 
+# DHCP options to request
+request_opts=("-O" "hostname")
+request_opts+=("-O" "ntpsrv")
+request_opts+=("-O" "domain")
+request_opts+=("-O" "wpad")
+request_opts+=("-O" "search")
+request_opts+=("-O" "nisdomain")
+
 # udhcpc
 for i in 1 1 1 fail; do
 	[ "$i" = "fail" ] && emergency_shell "DHCP failed 3 times... cannot continue."
 	udhcpc -t 4 -T 3 -f -n -q \
 		-i "${MAIN_NETIF}" \
-		"${SLX_PXE_CLIENT_IP:+-r $SLX_PXE_CLIENT_IP}" \
-		"${UUID:+-x 0x3d:$UUID}" \
-		-O ntpsrv -O domain -O wpad -O search -O nisdomain \
+		"${request_opts[@]}" \
+		"${additional_opts[@]}" \
 		-s "/usr/local/bin/udhcpc-trigger"
 	# success?
 	[ "$?" -eq 0 ] && break
@@ -110,3 +129,5 @@ done
 
 set +x
 } &>> "/run/openslx/initramfs-network.log.$$"
+
+
diff --git a/builder/modules.d/slx-network/scripts/setup-bootif-network.stage4 b/builder/modules.d/slx-network/scripts/setup-bootif-network.stage4
index 61f925d0..4f41dfed 100755
--- a/builder/modules.d/slx-network/scripts/setup-bootif-network.stage4
+++ b/builder/modules.d/slx-network/scripts/setup-bootif-network.stage4
@@ -21,7 +21,10 @@ readonly MAIN_NETIF
 
 # set default options
 declare -a udhcpc_opts
+udhcpc_opts+=("-T" "1")
+udhcpc_opts+=("-A" "5")
 udhcpc_opts+=("-t" "8")
+udhcpc_opts+=("-O" "hostname")
 udhcpc_opts+=("-O" "domain")
 udhcpc_opts+=("-O" "nissrv")
 udhcpc_opts+=("-O" "nisdomain")
diff --git a/builder/modules.d/slx-network/scripts/udhcpc-trigger.stage4 b/builder/modules.d/slx-network/scripts/udhcpc-trigger.stage4
index b4dfeafa..d7009dc6 100755
--- a/builder/modules.d/slx-network/scripts/udhcpc-trigger.stage4
+++ b/builder/modules.d/slx-network/scripts/udhcpc-trigger.stage4
@@ -66,7 +66,11 @@ case "$1" in
 		ip addr add "$ip/$(ipcalc -s -p "$ip" "$subnet" | sed s/.*=//)" dev "$interface"
 		# Set default route, if given
 		if [ -n "$router" ]; then
-			ip route replace default via "$router"
+			# Only replace route if it's the same interface as the current default route, or we don't have any
+			current="$( ip route show | awk '{ if ($1 == "default") {print $5; exit 0}}' )"
+			if [ -z "$current" ] || [ "$interface" = "$current" ]; then
+				ip route replace default via "$router"
+			fi
 		fi
 		
 		# get domain, hostname and thus fqdn from DNS
diff --git a/builder/modules.d/slx-network/services/udhcpc-bootif.service b/builder/modules.d/slx-network/services/udhcpc-bootif.service
index 21a5de3c..71a721dc 100644
--- a/builder/modules.d/slx-network/services/udhcpc-bootif.service
+++ b/builder/modules.d/slx-network/services/udhcpc-bootif.service
@@ -1,12 +1,12 @@
 [Unit]
 Description=DHCP Client for the main boot interface
-Before=network.target
 Requires=systemd-tmpfiles-setup.service
 After=systemd-tmpfiles-setup.service
+DefaultDependencies=no
 
 [Service]
 Type=forking
 ExecStart=/opt/openslx/scripts/setup-bootif-network
 
 [Install]
-WantedBy=network.target
+WantedBy=sysinit.target
diff --git a/builder/modules.d/slx-splash/module-setup.sh b/builder/modules.d/slx-splash/module-setup.sh
index 05542269..29a85648 100755
--- a/builder/modules.d/slx-splash/module-setup.sh
+++ b/builder/modules.d/slx-splash/module-setup.sh
@@ -10,5 +10,6 @@ depends() {
 install() {
 	cp "$moddir/data/splash.ppm.gz" "$initdir/etc/splash.ppm.gz"
 	inst_hook pre-trigger 10 "$moddir/scripts/slx-splash.sh"
+	inst_hook pre-pivot 00 "$moddir/scripts/slx-splash-exam.sh"
 	inst_hook pre-pivot 20 "$moddir/scripts/restore-cursor.sh"
 }
diff --git a/builder/modules.d/slx-splash/scripts/slx-splash-exam.sh b/builder/modules.d/slx-splash/scripts/slx-splash-exam.sh
new file mode 100644
index 00000000..b2bf4f53
--- /dev/null
+++ b/builder/modules.d/slx-splash/scripts/slx-splash-exam.sh
@@ -0,0 +1,15 @@
+#!/usr/bin/env bash
+
+. /etc/openslx
+
+if [ -n "$SLX_EXAM" ]; then
+	if [ -e "/etc/splash.ppm.gz" ]; then
+		systemd-preserve-process-marker /bin/busybox fbsplash -b -s "/etc/splash.ppm.gz" &
+	elif [ -e "/etc/splash.ppm" ]; then
+		systemd-preserve-process-marker /bin/busybox fbsplash -b -s "/etc/splash.ppm" &
+	else
+		echo "Splash screen requested, but not found in initramfs..."
+	fi
+fi
+
+:
diff --git a/builder/modules.d/slx-uuid/bad-uuid-defaults.conf b/builder/modules.d/slx-uuid/bad-uuid-defaults.conf
index aaf59a7d..dab53d07 100644
--- a/builder/modules.d/slx-uuid/bad-uuid-defaults.conf
+++ b/builder/modules.d/slx-uuid/bad-uuid-defaults.conf
@@ -1,8 +1,10 @@
 00000000-0000-0000-0000-000000000000
+00000000-0000-0000-0000-000000000001
 03000200-0400-0500-0006-000700080009
 11111111-2222-3333-4444-555555555555
 44454C4C-2000-1020-8020-A0C04F202020
 4C4C4544-0000-2010-8020-80C04F202020
 4C4C4544-0046-3310-805A-B6C04F4B4D31
+58585858-5858-5858-5858-585858585858
 A023157C-F692-11DE-977C-7F0F26276F33
 FFFFFFFF-FFFF-FFFF-FFFF-FFFFFFFFFFFF
diff --git a/builder/modules.d/slx-uuid/module-setup.sh b/builder/modules.d/slx-uuid/module-setup.sh
index 569b5155..1e550136 100755
--- a/builder/modules.d/slx-uuid/module-setup.sh
+++ b/builder/modules.d/slx-uuid/module-setup.sh
@@ -13,7 +13,16 @@ depends() {
 }
 install() {
 	mkdir -p "$initdir/etc/bad-uuid.d"
-	inst_simple "$moddir/bad-uuid-defaults.conf" "/etc/bad-uuid.d/bad-uuid-defaults.conf"
+	# check if we have an uuid blacklists installed by openslx/mltk on this system
+	if [ "$(ls -A /opt/openslx/bad-uuid.d)" ]; then
+		for blacklist in "/opt/openslx/bad-uuid.d"/* ]; do
+			inst_simple "$blacklist" "/etc/bad-uuid.d/${blacklist##*/}"
+		done
+	else
+		# use this module's default blacklist
+		inst_simple "$moddir/bad-uuid-defaults.conf" "/etc/bad-uuid.d/bad-uuid-defaults.conf"
+	fi
+
 	inst_multiple dmidecode
 	inst_hook pre-udev 05 "$moddir/scripts/get-system-uuid.sh"
 	inst_hook pre-pivot 10 "$moddir/scripts/copy-system-uuid-to-newroot.sh"