From 271e8eef2d962c3493a856899a50784c32528bb8 Mon Sep 17 00:00:00 2001
From: minoplhy <c@3qx.nl>
Date: Sun, 3 Nov 2024 22:17:34 +0700
Subject: [PATCH] alpine-initramfs-dropbear: init

---
 alpine-initramfs-dropbear/README.md           |  111 ++
 .../dropbear/unlock_disk                      |   29 +
 .../features.d/dropbear.files                 |    3 +
 .../features.d/dropbear.modules               |    3 +
 alpine-initramfs-dropbear/initramfs-dropbear  | 1055 +++++++++++++++++
 5 files changed, 1201 insertions(+)
 create mode 100644 alpine-initramfs-dropbear/README.md
 create mode 100644 alpine-initramfs-dropbear/dropbear/unlock_disk
 create mode 100644 alpine-initramfs-dropbear/features.d/dropbear.files
 create mode 100644 alpine-initramfs-dropbear/features.d/dropbear.modules
 create mode 100644 alpine-initramfs-dropbear/initramfs-dropbear

diff --git a/alpine-initramfs-dropbear/README.md b/alpine-initramfs-dropbear/README.md
new file mode 100644
index 0000000..73bb05e
--- /dev/null
+++ b/alpine-initramfs-dropbear/README.md
@@ -0,0 +1,111 @@
+# Alpine Dropbear Initramfs
+This script took a huge references from:
+
+* [https://github.com/Deeplerg/fork-alpine-initramfs-dropbear](https://github.com/Deeplerg/fork-alpine-initramfs-dropbear)
+
+* [https://github.com/mk-f/alpine-initramfs-dropbear](https://github.com/mk-f/alpine-initramfs-dropbear)
+
+* [https://gitlab.alpinelinux.org/alpine/mkinitfs/-/blob/master/initramfs-init.in](https://gitlab.alpinelinux.org/alpine/mkinitfs/-/blob/master/initramfs-init.in)
+
+This script is modified from [alpine/mkinitfs - initramfs-init.in](https://gitlab.alpinelinux.org/alpine/mkinitfs/-/blob/master/initramfs-init.in)
+
+significant changes:
+
+* Add dropbear
+
+* Add dropbear session timer, this make typical decryption still works even if dropbear/network is broken
+
+Please install `dropbear` before continuing
+
+1. copy `dropbear/unlock_disk` to `/etc/dropbear/unlock_disk`
+2. copy `authorized_keys` to `/etc/dropbear/authorized_keys`
+3. copy `features.d` to /`etc/mkinitfs/features.d`
+
+Note: if you're using Deeplerg/mk-f scripts before don't forget to change `unlock_disk` as i modified that one too.
+
+### /etc/mkinitfs.conf
+`features="ata base ide scsi usb virtio ext4 cryptsetup keymap dropbear network"`
+* features+= `dropbear` `network`
+
+### /etc/update-extlinux.conf
+`modules=sd-mod,usb-storage,ext4,ata_piix,virtio_net,e1000e,virtio_pci`
+* if network is not working (/sys/class/net/*/address not found etc.) try adding `e1000e` or `virtio_net` `virtio_pci`
+
+`default_kernel_opts="cryptroot=UUID=xxx cryptdm=root quiet rootfstype=ext4 dropbear=<dropbear_port> ip=<ip>>"`
+* ip= can be both static and dhcp(if supported) `ip=<ip>::<gw>:<mask>::<interface>` `ip=dhcp`
+
+
+`update-extlinux`
+
+`mkinitfs -i path/to/initramfs-dropbear <Kernel Version(from /lib/modules) incase in emergency CD>`
+
+## Full Diff:
+```diff
+325a326,367
+> setup_dropbear() {
+> 	local port="${KOPT_dropbear}"
+> 	local keys=""
+> 
+> 	# set the unlock_disc script as shell for root
+> 	sed -i 's|\(root:x:0:0:root:/root:\).*$|\1/etc/dropbear/unlock_disk|' /etc/passwd
+> 	echo '/etc/dropbear/unlock_disk' > /etc/shells
+> 
+> 	# transfer authorized_keys
+> 	mkdir /root/.ssh
+> 	cp /etc/dropbear/authorized_keys /root/.ssh/authorized_keys
+> 
+> 	dropbear -R -E -s -j -k -p $port
+> 
+> 	# [ -b /dev/mapper/${KOPT_cryptdm} ] 
+> 	#|| return 1
+> }
+> 
+> # A simple timer that do nothing but prevent any process to run
+> setup_dropbear_timer() {
+> 	timer=200
+>     while [ $timer -gt 0 ]; do
+>         printf "\r%d Press 'c' to cancel or 'p' to add 30 seconds " "$timer"
+> 		
+>         if read -t 1 -r timer_control; then
+> 			case $timer_control in
+> 				"c") return 0 ;;
+> 				"p") timer=$((timer + 30)) ;;
+> 			esac
+>         fi
+> 
+> 		# Check for /tmp/timer_kill to terminate this counter
+> 		if [ -f /tmp/timer_kill ]; then
+> 			return 0
+> 		fi
+> 
+>         sleep 1
+>         timer=$((timer - 1))
+>     done
+> 	printf "\n"
+> }
+> 
+453c495
+< 	s390x_net dasd ssh_key BOOTIF zfcp uevent_buf_size aoe aoe_iflist aoe_mtu wireguard"
+---
+> 	s390x_net dasd ssh_key BOOTIF zfcp uevent_buf_size aoe aoe_iflist aoe_mtu wireguard dropbear"
+581c623,633
+< if [ -n "$KOPT_cryptroot" ]; then
+---
+> if [ -n "$KOPT_dropbear" ]; then
+>  	if [ -n "$KOPT_cryptroot" ]; then
+> 		configure_ip
+>  		setup_dropbear
+> 		setup_dropbear_timer
+> 		#|| echo "Failed to setup dropbear"
+>  	fi
+> fi
+> 
+> # Add Workaround for dropbear
+> if [ -n "$KOPT_cryptroot" ] && [ ! -b /dev/mapper/"${KOPT_cryptdm}" ]; then
+1003c1055
+< reboot
+---
+> reboot
+\ No newline at end of file
+
+```
\ No newline at end of file
diff --git a/alpine-initramfs-dropbear/dropbear/unlock_disk b/alpine-initramfs-dropbear/dropbear/unlock_disk
new file mode 100644
index 0000000..bf2db55
--- /dev/null
+++ b/alpine-initramfs-dropbear/dropbear/unlock_disk
@@ -0,0 +1,29 @@
+#!/bin/sh
+
+set -- $(cat /proc/cmdline)
+
+for opt; do
+	case "$opt" in
+		cryptroot=*)
+			KOPT_cryptroot=${opt#cryptroot=}
+			continue
+			;;
+		cryptdm=*)
+			KOPT_cryptdm=${opt#cryptdm=}
+			continue
+			;;
+		root=*)
+			KOPT_root=${opt#root=}
+			continue
+			;;
+	esac
+done
+
+while [ ! -b /dev/mapper/${KOPT_cryptdm} ]; do
+	/sbin/nlplug-findfs -c ${KOPT_cryptroot} -m ${KOPT_cryptdm} ${KOPT_debug_init:+-d} -p /sbin/mdev ${KOPT_root}
+	sleep 2
+done
+
+# make a new file to kill the timer
+echo "" > /tmp/timer_kill
+killall -9 dropbear
\ No newline at end of file
diff --git a/alpine-initramfs-dropbear/features.d/dropbear.files b/alpine-initramfs-dropbear/features.d/dropbear.files
new file mode 100644
index 0000000..6644349
--- /dev/null
+++ b/alpine-initramfs-dropbear/features.d/dropbear.files
@@ -0,0 +1,3 @@
+/usr/sbin/dropbear
+/sbin/cryptsetup
+/etc/dropbear/*
\ No newline at end of file
diff --git a/alpine-initramfs-dropbear/features.d/dropbear.modules b/alpine-initramfs-dropbear/features.d/dropbear.modules
new file mode 100644
index 0000000..6c771f1
--- /dev/null
+++ b/alpine-initramfs-dropbear/features.d/dropbear.modules
@@ -0,0 +1,3 @@
+kernel/crypto/*
+kernel/arch/*/crypto/*
+kernel/drivers/md/dm-crypt.ko
\ No newline at end of file
diff --git a/alpine-initramfs-dropbear/initramfs-dropbear b/alpine-initramfs-dropbear/initramfs-dropbear
new file mode 100644
index 0000000..cd0448c
--- /dev/null
+++ b/alpine-initramfs-dropbear/initramfs-dropbear
@@ -0,0 +1,1055 @@
+#!/bin/sh
+
+# this is the init script version
+VERSION=@VERSION@
+SINGLEMODE=no
+sysroot="$ROOT"/sysroot
+splashfile=/.splash.ctrl
+repofile="$ROOT"/tmp/repositories
+
+# some helpers
+ebegin() {
+	last_emsg="$*"
+	echo "$last_emsg..." > "$ROOT"/dev/kmsg
+	[ "$KOPT_quiet" = yes ] && return 0
+	echo -n " * $last_emsg: "
+}
+eend() {
+	local msg
+	if [ "$1" = 0 ] || [ $# -lt 1 ] ; then
+		echo "$last_emsg: ok." > "$ROOT"/dev/kmsg
+		[ "$KOPT_quiet" = yes ] && return 0
+		echo "ok."
+	else
+		shift
+		echo "$last_emsg: failed. $*" > "$ROOT"/dev/kmsg
+		if [ "$KOPT_quiet" = "yes" ]; then
+			echo -n "$last_emsg "
+		fi
+		echo "failed. $*"
+		echo "initramfs emergency recovery shell launched. Type 'exit' to continue boot"
+		/bin/busybox sh
+	fi
+}
+
+unpack_apkovl() {
+	local ovl="$1"
+	local dest="$2"
+	local suffix=${ovl##*.}
+	local i
+	ovlfiles=/tmp/ovlfiles
+	if [ "$suffix" = "gz" ]; then
+		tar -C "$dest" -zxvf "$ovl" > $ovlfiles
+		return $?
+	fi
+
+	# we need openssl. let apk handle deps
+	apk add --quiet --initdb --repositories-file $repofile openssl || return 1
+
+	if ! openssl list -1 -cipher-commands | grep "^$suffix$" > /dev/null; then
+		errstr="Cipher $suffix is not supported"
+		return 1
+	fi
+	local count=0
+	# beep
+	echo -e "\007"
+	while [ $count -lt 3 ]; do
+		openssl enc -d -$suffix -in "$ovl" | tar --numeric-owner \
+			-C "$dest" -zxv >$ovlfiles 2>/dev/null && return 0
+		count=$(( $count + 1 ))
+	done
+	ovlfiles=
+	return 1
+}
+
+# find mount dir and mount opts for given device in an fstab
+get_fstab_mount_info() {
+	local search_dev="$1"
+	local fstab="$2"
+	local mntopts=
+	case "$search_dev" in
+	UUID*|LABEL*) search_dev=$(findfs "$search_dev");;
+	esac
+	[ -r "$fstab" ] || return 1
+	local search_maj_min=$(stat -L -c '%t,%T' $search_dev)
+	while read dev mnt fs mntopts chk; do
+		case "$dev" in
+		UUID*|LABEL*) dev=$(findfs "$dev");;
+		esac
+		if [ -b "$dev" ] || [ -n "$ROOT" ]; then
+			local maj_min=$(stat -L -c '%t,%T' $dev)
+			if [ "$maj_min" = "$search_maj_min" ]; then
+				echo "$mnt $mntopts"
+				return
+			fi
+		fi
+	done < $fstab
+}
+
+#  add a boot service to $sysroot
+rc_add() {
+	mkdir -p $sysroot/etc/runlevels/$2
+	ln -sf /etc/init.d/$1 $sysroot/etc/runlevels/$2/$1
+}
+
+# Recursively resolve tty aliases like console or tty0
+list_console_devices() {
+	if ! [ -e "$ROOT"/sys/class/tty/$1/active ]; then
+		echo $1
+		return
+	fi
+
+	for dev in $(cat "$ROOT"/sys/class/tty/$1/active); do
+		list_console_devices $dev
+	done
+}
+
+detect_serial_consoles() {
+	if [ -f "$ovl" ] || [ "$KOPT_autodetect_serial" = "no" ]; then
+		return
+	fi
+	local n=$(awk '$7 ~ /CTS/ || $7 ~ /DSR/ { print $1 }' "$ROOT"/proc/tty/driver/serial 2>/dev/null)
+	if [ -n "$n" ]; then
+		echo ttyS${n%:}
+	fi
+	for i in "$ROOT"/sys/class/tty/*; do
+		if [ -e "$i"/device ]; then
+			echo ${i##*/}
+		fi
+	done
+}
+
+setup_inittab_console() {
+	term=vt100
+	# Inquire the kernel for list of console= devices
+	consoles="$(for c in console $KOPT_consoles $(detect_serial_consoles); do list_console_devices $c; done)"
+	for tty in $consoles; do
+		# ignore tty devices that gives I/O error
+		if ! stty -g -F /dev/$tty >/dev/null 2>/dev/null; then
+			continue
+		fi
+		# do nothing if inittab already have the tty set up
+		if ! grep -q "^$tty:" $sysroot/etc/inittab 2>/dev/null; then
+			echo "# enable login on alternative console" \
+				>> $sysroot/etc/inittab
+			# Baudrate of 0 keeps settings from kernel
+			echo "$tty::respawn:/sbin/getty -L 0 $tty $term" \
+				>> $sysroot/etc/inittab
+		fi
+		if [ -e "$sysroot"/etc/securetty ] && ! grep -q -w "$tty" "$sysroot"/etc/securetty; then
+			echo "$tty" >> "$sysroot"/etc/securetty
+		fi
+	done
+}
+
+# collect ethernet interfaces, sorted by index
+ethernets() {
+	for i in "$ROOT/sys/class/net/"*; do
+		local iface="${i##*/}"
+		if [ -d "$i/device" ]; then
+			echo "$(cat "$i/ifindex") $iface"
+		fi
+	done | sort -n | awk '{print $2}'
+}
+
+# find the interface that is has operstate up
+find_first_interface_up() {
+	local n=0
+	[ $# -eq 0 ] && return 0
+	while [ "$n" -le "${LINK_WAIT_MAX:-40}" ]; do
+		for i in "$@"; do
+			if grep -q -F -x "up" "$ROOT/sys/class/net/$i/operstate"; then
+				echo "$i"
+				return
+			fi
+		done
+		sleep 0.1
+		n=$((n+1))
+	done
+	return 1
+}
+
+# if "ip=dhcp" is specified on the command line, we obtain an IP address
+# using udhcpc. we do this now and not by enabling kernel-mode DHCP because
+# kernel-model DHCP appears to require that network drivers be built into
+# the kernel rather than as modules. At this point all applicable modules
+# in the initrd should have been loaded.
+#
+# You need af_packet.ko available as well modules for your Ethernet card.
+#
+# See https://www.kernel.org/doc/Documentation/filesystems/nfs/nfsroot.txt
+# for documentation on the format.
+#
+# Valid syntaxes:
+#   ip=client-ip:server-ip:gw-ip:netmask:hostname:device:autoconf:
+#     :dns0-ip:dns1-ip:ntp0-ip
+#   ip=dhcp
+#   "server-ip", "hostname" and "ntp0-ip" are not supported here.
+# Default (when configure_ip is called without setting ip=):
+#   ip=dhcp
+#
+configure_ip() {
+	[ -n "$MAC_ADDRESS" ] && return
+
+	local IFS=':'
+	# shellcheck disable=SC2086
+	set -- ${KOPT_ip:-dhcp}
+	unset IFS
+
+	local client_ip="$1"
+	local gw_ip="$3"
+	local netmask="$4"
+	local iface="$6"
+	local autoconf="$7"
+	local dns1="$8"
+	local dns2="$9"
+
+	case "$client_ip" in
+		off|none) return;;
+		dhcp) autoconf="dhcp";;
+	esac
+
+	if [ -e "$ROOT"/etc/mactab ]; then
+		$MOCK nameif -s
+	fi
+
+	if [ -z "$iface" ] && [ -n "$KOPT_BOOTIF" ]; then
+		mac=$(printf "%s\n" "$KOPT_BOOTIF"|sed 's/^01-//;s/-/:/g')
+		iface=$(grep -l "$mac" "$ROOT"/sys/class/net/*/address | awk -F/ '{print $(NF-1); exit}')
+	fi
+
+	if [ -z "$iface" ]; then
+		# shellcheck disable=SC2046
+		set -- $(ethernets)
+		for i in "$@"; do
+			$MOCK ip link set dev "$i" up
+		done
+		iface=$(find_first_interface_up "$@") || iface="$1"
+
+		# we will use the found interface later so lets keep it up
+		for i in "$@"; do
+			if [ "$i" != "$iface" ]; then
+				$MOCK ip link set dev "$i" down
+			fi
+		done
+	fi
+
+	if [ -z "$iface" ]; then
+		echo "ERROR: IP requested but no network interface was found"
+		return 1
+	fi
+
+	if [ "$autoconf" = "dhcp" ]; then
+		# automatic configuration
+		if [ ! -e "$ROOT"/usr/share/udhcpc/default.script ]; then
+			echo "ERROR: DHCP requested but not present in initrd"
+			return 1
+		fi
+		ebegin "Obtaining IP via DHCP ($iface)"
+		$MOCK ip link set dev "$iface" up
+		$MOCK udhcpc -i "$iface" -f -q
+		eend $?
+	else
+		# manual configuration
+		if [ -z "$client_ip" ] && [ -z "$netmask" ]; then
+			return
+		fi
+		ebegin "Setting IP ($iface)"
+		if ifconfig "$iface" "$client_ip" netmask "$netmask"; then
+			[ -z "$gw_ip" ] || ip route add 0.0.0.0/0 via "$gw_ip" dev "$iface"
+		fi
+		eend $?
+	fi
+
+	# Never executes if variables are empty
+	for i in $dns1 $dns2; do
+		echo "nameserver $i" >> /etc/resolv.conf
+	done
+
+	MAC_ADDRESS=$(cat "$ROOT/sys/class/net/$iface/address")
+}
+
+# relocate mountpoint according given fstab and set mount options
+remount_fstab_entry() {
+	local fstab="${1}"
+	local dir=
+	if ! [ -e "$repofile" ]; then
+		return
+	fi
+	echo "$ovl" | cat - "$repofile" | while read dir; do
+		# skip http(s)/ftp repos for netboot
+		if [ -z "$dir" ] || ! [ -d "$ROOT/$dir" -o -f "$ROOT/$dir" ]; then
+			continue
+		fi
+		local dev=$(df -P "$dir" | tail -1 | awk '{print $1}')
+		local mntinfo="$(get_fstab_mount_info "$dev" "$fstab")"
+		local mnt="${mntinfo% *}"
+		local mntopts="${mntinfo#* }"
+		if [ -n "$mnt" ]; then
+			local oldmnt=$(awk -v d=$ROOT$dev '$1==d {print $2}' "$ROOT"/proc/mounts 2>/dev/null)
+			if [ "$oldmnt" != "$mnt" ]; then
+				mkdir -p "$mnt"
+				$MOCK mount -o move "$oldmnt" "$mnt"
+			fi
+			if [ -n "$mntopts" ]; then
+				$MOCK mount -o remount,"$mntopts" "$mnt"
+			fi
+		fi
+	done
+}
+
+# find the dirs under ALPINE_MNT that are boot repositories
+find_boot_repositories() {
+	if [ -n "$ALPINE_REPO" ]; then
+		echo "$ALPINE_REPO" | tr ',' '\n'
+	else
+		find /media/* -maxdepth 3 -name .boot_repository -type f \
+			| sed 's:/.boot_repository$::'
+	fi
+}
+
+setup_nbd() {
+	$MOCK modprobe -q nbd max_part=8 || return 1
+	local IFS=, n=0
+	set -- $KOPT_nbd
+	unset IFS
+	for ops; do
+		local server="${ops%:*}"
+		local port="${ops#*:}"
+		local device="/dev/nbd${n}"
+		[ -b "$device" ] || continue
+		nbd-client "$server" "$port" "$device" && n=$((n+1))
+	done
+	[ "$n" != 0 ] || return 1
+}
+
+setup_dropbear() {
+	local port="${KOPT_dropbear}"
+	local keys=""
+
+	# set the unlock_disc script as shell for root
+	sed -i 's|\(root:x:0:0:root:/root:\).*$|\1/etc/dropbear/unlock_disk|' /etc/passwd
+	echo '/etc/dropbear/unlock_disk' > /etc/shells
+
+	# transfer authorized_keys
+	mkdir /root/.ssh
+	cp /etc/dropbear/authorized_keys /root/.ssh/authorized_keys
+
+	dropbear -R -E -s -j -k -p $port
+
+	# [ -b /dev/mapper/${KOPT_cryptdm} ] 
+	#|| return 1
+}
+
+# A simple timer that do nothing but prevent any process to run
+setup_dropbear_timer() {
+	timer=200
+    while [ $timer -gt 0 ]; do
+        printf "\r%d Press 'c' to cancel or 'p' to add 30 seconds " "$timer"
+		
+        if read -t 1 -r timer_control; then
+			case $timer_control in
+				"c") return 0 ;;
+				"p") timer=$((timer + 30)) ;;
+			esac
+        fi
+
+		# Check for /tmp/timer_kill to terminate this counter
+		if [ -f /tmp/timer_kill ]; then
+			return 0
+		fi
+
+        sleep 1
+        timer=$((timer - 1))
+    done
+	printf "\n"
+}
+
+setup_wireguard() {
+	$MOCK modprobe -q wireguard || return 1
+	local IFS=';'
+	set -- $KOPT_wireguard
+	unset IFS
+
+	local device="$1"
+	local ips="$2"
+	local config="${3:-/etc/wireguard/initrd.conf}"
+
+	local IFS=','
+	set -- $ips
+	unset IFS
+
+	$MOCK ip link add "$device" type wireguard
+	$MOCK wg setconf "$device" "$config"
+	$MOCK ip link set dev "$device" up
+
+	for addr in $@; do
+		$MOCK ip addr add dev "$device" "$addr"
+	done
+}
+
+rtc_exists() {
+	local rtc=
+	for rtc in /dev/rtc /dev/rtc[0-9]*; do
+		[ -e "$rtc" ] && break
+	done
+	[ -e "$rtc" ]
+}
+
+# This is used to predict if network access will be necessary
+is_url() {
+	case "$1" in
+	http://*|https://*|ftp://*)
+		return 0;;
+	*)
+		return 1;;
+	esac
+}
+
+# Do some tasks to make sure mounting the ZFS pool is A-OK
+prepare_zfs_root() {
+	local _root_vol=${KOPT_root#ZFS=}
+	local _root_pool=${_root_vol%%/*}
+
+	# Force import if this has been imported on a different system previously.
+	# Import normally otherwise
+	if [ "$KOPT_zfs_force" = 1 ]; then
+		zpool import -N -d /dev -f $_root_pool
+	else
+		zpool import -N -d /dev $_root_pool
+	fi
+
+
+	# Ask for encryption password
+	if [ $(zpool list -H -o feature@encryption $_root_pool) = "active" ]; then
+		local _encryption_root=$(zfs get -H -o value encryptionroot $_root_vol)
+		if [ "$_encryption_root" != "-" ]; then
+			eval zfs load-key $_encryption_root
+		fi
+	fi
+}
+
+want_tiny_cloud() {
+	if [ -f "$sysroot/etc/tiny-cloud.disabled" ]; then
+		return 1
+	fi
+	case "$KOPT_ds" in
+		nocloud*) return 0;;
+	esac
+	if grep -q "^ds=nocloud" "$ROOT"/sys/class/dmi/id/product_serial 2>/dev/null; then
+		return 0
+	fi
+	findfs LABEL=cidata >/dev/null 2>&1 || findfs LABEL=CIDATA >/dev/null 2>&1
+}
+
+/bin/busybox mkdir -p "$ROOT"/usr/bin \
+	"$ROOT"/usr/sbin \
+	"$ROOT"/proc \
+	"$ROOT"/sys \
+	"$ROOT"/dev \
+	"$sysroot" \
+	"$ROOT"/media/cdrom \
+	"$ROOT"/media/usb \
+	"$ROOT"/tmp \
+	"$ROOT"/etc \
+	"$ROOT"/run/cryptsetup
+
+# Spread out busybox symlinks and make them available without full path
+/bin/busybox --install -s
+export PATH="$PATH:/usr/bin:/bin:/usr/sbin:/sbin"
+
+# Make sure /dev/null is a device node. If /dev/null does not exist yet, the command
+# mounting the devtmpfs will create it implicitly as an file with the "2>" redirection.
+# The -c check is required to deal with initramfs with pre-seeded device nodes without
+# error message.
+[ -c /dev/null ] || $MOCK mknod -m 666 /dev/null c 1 3
+
+$MOCK mount -t sysfs -o noexec,nosuid,nodev sysfs /sys
+$MOCK mount -t devtmpfs -o exec,nosuid,mode=0755,size=2M devtmpfs /dev 2>/dev/null \
+	|| $MOCK mount -t tmpfs -o exec,nosuid,mode=0755,size=2M tmpfs /dev
+
+# Make sure /dev/kmsg is a device node. Writing to /dev/kmsg allows the use of the
+# earlyprintk kernel option to monitor early init progress. As above, the -c check
+# prevents an error if the device node has already been seeded.
+[ -c /dev/kmsg ] || $MOCK mknod -m 660 /dev/kmsg c 1 11
+
+$MOCK mount -t proc -o noexec,nosuid,nodev proc /proc
+# pty device nodes (later system will need it)
+[ -c /dev/ptmx ] || $MOCK mknod -m 666 /dev/ptmx c 5 2
+[ -d /dev/pts ] || $MOCK mkdir -m 755 /dev/pts
+$MOCK mount -t devpts -o gid=5,mode=0620,noexec,nosuid devpts /dev/pts
+
+# shared memory area (later system will need it)
+mkdir -p "$ROOT"/dev/shm
+$MOCK mount -t tmpfs -o nodev,nosuid,noexec shm /dev/shm
+
+
+# read the kernel options. we need surve things like:
+#  acpi_osi="!Windows 2006" xen-pciback.hide=(01:00.0)
+set -- $(cat "$ROOT"/proc/cmdline)
+
+myopts="autodetect_serial chart cryptroot cryptdm cryptheader cryptoffset
+	cryptdiscards cryptkey debug_init ds init init_args keep_apk_new modules
+	pkgs quiet root_size root usbdelay ip alpine_repo apkovl splash
+	blacklist overlaytmpfs overlaytmpfsflags rootfstype rootflags nbd resume resume_offset
+	s390x_net dasd ssh_key BOOTIF zfcp uevent_buf_size aoe aoe_iflist aoe_mtu wireguard dropbear"
+
+for opt; do
+	case "$opt" in
+	s|single|1)
+		SINGLEMODE=yes
+		continue
+		;;
+	console=*)
+		opt="${opt#*=}"
+		KOPT_consoles="${opt%%,*} $KOPT_consoles"
+		switch_root_opts="-c /dev/${opt%%,*}"
+		continue
+		;;
+	esac
+
+	for i in $myopts; do
+		case "$opt" in
+		$i=*)	eval "KOPT_${i}"='${opt#*=}';;
+		$i)	eval "KOPT_${i}=yes";;
+		no$i)	eval "KOPT_${i}=no";;
+		esac
+	done
+done
+
+echo "Alpine Init $VERSION" > "$ROOT"/dev/kmsg
+[ "$KOPT_quiet" = yes ] || echo "Alpine Init $VERSION"
+
+# enable debugging if requested
+[ -n "$KOPT_debug_init" ] && set -x
+
+# set default values
+: ${KOPT_init:=/sbin/init}
+
+# pick first keymap if found
+for map in "$ROOT"/etc/keymap/*; do
+	if [ -f "$map" ]; then
+		ebegin "Setting keymap ${map##*/}"
+		zcat "$map" | loadkmap
+		eend
+		break
+	fi
+done
+
+# start bootcharting if wanted
+if [ "$KOPT_chart" = yes ]; then
+	ebegin "Starting bootchart logging"
+	$MOCK /sbin/bootchartd start-initfs
+	eend 0
+fi
+
+# The following values are supported:
+#   alpine_repo=auto	 -- default, search for .boot_repository
+#   alpine_repo=http://...   -- network repository
+ALPINE_REPO=${KOPT_alpine_repo}
+[ "$ALPINE_REPO" = "auto" ] && ALPINE_REPO=
+
+# hide kernel messages
+[ "$KOPT_quiet" = yes ] && dmesg -n 1
+
+# optional blacklist
+if [ -n "$KOPT_blacklist" ]; then
+	mkdir -p "$ROOT"/etc/modprobe.d
+	for i in $(echo "$KOPT_blacklist" | tr ',' ' '); do
+		echo "blacklist $i" >> "$ROOT"/etc/modprobe.d/boot-opt-blacklist.conf
+	done
+fi
+
+# determine if we are going to need networking
+if [ -n "$KOPT_ip" ] || [ -n "$KOPT_nbd" ] || \
+	is_url "$KOPT_apkovl" || is_url "$ALPINE_REPO"; then
+
+	do_networking=true
+else
+	do_networking=false
+fi
+
+if [ -n "$KOPT_zfcp" ]; then
+	$MOCK modprobe zfcp
+	for _zfcp in $(echo "$KOPT_zfcp" | tr ',' ' ' | tr [A-Z] [a-z]); do
+		echo 1 > /sys/bus/ccw/devices/"${_zfcp%%:*}"/online
+	done
+fi
+
+if [ -n "$KOPT_dasd" ]; then
+	for mod in dasd_mod dasd_eckd_mod dasd_fba_mod; do
+		$MOCK modprobe $mod
+	done
+	for _dasd in $(echo "$KOPT_dasd" | tr ',' ' ' | tr [A-Z] [a-z]); do
+		echo 1 > /sys/bus/ccw/devices/"${_dasd%%:*}"/online
+	done
+fi
+
+if [ "${KOPT_s390x_net%%,*}" = "qeth_l2" ]; then
+	for mod in qeth qeth_l2 qeth_l3; do
+		$MOCK modprobe $mod
+	done
+	_channel="$(echo ${KOPT_s390x_net#*,} | tr [A-Z] [a-z])"
+	echo "$_channel" > /sys/bus/ccwgroup/drivers/qeth/group
+	echo 1 > /sys/bus/ccwgroup/drivers/qeth/"${_channel%%,*}"/layer2
+	echo 1 > /sys/bus/ccwgroup/drivers/qeth/"${_channel%%,*}"/online
+fi
+
+# make sure we load zfs module if root=ZFS=...
+rootfstype=${KOPT_rootfstype}
+if [ -z "$rootfstype" ]; then
+	case "$KOPT_root" in
+	ZFS=*) rootfstype=zfs ;;
+	esac
+fi
+
+# load available drivers to get access to modloop media
+ebegin "Loading boot drivers"
+
+$MOCK modprobe -a $(echo "$KOPT_modules $rootfstype" | tr ',' ' ' ) loop squashfs simpledrm 2> /dev/null
+if [ -f "$ROOT"/etc/modules ] ; then
+	sed 's/\#.*//g' < /etc/modules |
+	while read module args; do
+		$MOCK modprobe -q $module $args
+	done
+fi
+eend 0
+
+# workaround for vmware
+if grep -q VMware "$ROOT"/sys/devices/virtual/dmi/id/sys_vendor 2>/dev/null; then
+	$MOCK modprobe -a ata_piix mptspi sr-mod
+fi
+
+if [ -n "$KOPT_dropbear" ]; then
+ 	if [ -n "$KOPT_cryptroot" ]; then
+		configure_ip
+ 		setup_dropbear
+		setup_dropbear_timer
+		#|| echo "Failed to setup dropbear"
+ 	fi
+fi
+
+# Add Workaround for dropbear
+if [ -n "$KOPT_cryptroot" ] && [ ! -b /dev/mapper/"${KOPT_cryptdm}" ]; then
+	cryptopts="-c ${KOPT_cryptroot}"
+	if [ "$KOPT_cryptdiscards" = "yes" ]; then
+		cryptopts="$cryptopts -D"
+	fi
+	if [ -n "$KOPT_cryptdm" ]; then
+		cryptopts="$cryptopts -m ${KOPT_cryptdm}"
+	fi
+	if [ -n "$KOPT_cryptheader" ]; then
+		cryptopts="$cryptopts -H ${KOPT_cryptheader}"
+	fi
+	if [ -n "$KOPT_cryptoffset" ]; then
+		cryptopts="$cryptopts -o ${KOPT_cryptoffset}"
+	fi
+	if [ "$KOPT_cryptkey" = "yes" ]; then
+		cryptopts="$cryptopts -k /crypto_keyfile.bin"
+	elif [ -n "$KOPT_cryptkey" ]; then
+		cryptopts="$cryptopts -k ${KOPT_cryptkey}"
+	fi
+fi
+
+if [ -n "$KOPT_wireguard" ]; then
+	configure_ip
+	setup_wireguard || echo "Failed to setup wireguard tunnel."
+fi
+
+if [ -n "$KOPT_nbd" ]; then
+	# TODO: Might fail because nlplug-findfs hasn't plugged eth0 yet
+	configure_ip
+	setup_nbd || echo "Failed to setup nbd device."
+fi
+
+if [ -n "$KOPT_aoe" ]; then
+	if [ -n "$KOPT_aoe_iflist" ]; then
+		for iface in $(echo "$KOPT_aoe_iflist" | tr ',' ' '); do
+			$MOCK ip link set dev "$iface" up
+			if [ -n "$KOPT_aoe_mtu" ]; then
+				$MOCK ip link set dev "$iface" mtu "$KOPT_aoe_mtu"
+			fi
+		done
+		$MOCK modprobe aoe aoe_iflist="$KOPT_aoe_iflist"
+	else
+		$MOCK modprobe aoe
+	fi
+	if [ "$KOPT_aoe" != "yes" ]; then
+		for target in $(echo "$KOPT_aoe" | tr ',' ' '); do
+			while [ ! -e /dev/etherd/e$target ]; do
+					echo discover "$target" >>/dev/etherd/discover
+					sleep 1
+			done
+		done
+	fi
+fi
+
+# zpool reports /dev/zfs missing if it can't read /etc/mtab
+ln -s /proc/mounts "$ROOT"/etc/mtab
+
+# check if root=... was set
+if [ -n "$KOPT_root" ]; then
+	# run nlplug-findfs before SINGLEMODE so we load keyboard drivers
+	ebegin "Mounting root"
+	$MOCK nlplug-findfs $cryptopts -p /sbin/mdev ${KOPT_debug_init:+-d} \
+		${KOPT_uevent_buf_size:+-U $KOPT_uevent_buf_size} \
+		$KOPT_root
+
+	if [ "$SINGLEMODE" = "yes" ]; then
+		echo "Entering single mode. Type 'exit' to continue booting."
+		sh
+	fi
+
+	if echo "$KOPT_modules $rootfstype" | grep -qw btrfs; then
+		/sbin/btrfs device scan >/dev/null || \
+			echo "Failed to scan devices for btrfs filesystem."
+	fi
+
+	if [ -n "$KOPT_resume" ]; then
+		echo "Resume from disk"
+		if [ -e $ROOT/sys/power/resume ]; then
+			case "$KOPT_resume" in
+			UUID*|LABEL*) resume_dev=$(findfs "$KOPT_resume");;
+			*) resume_dev="$KOPT_resume";;
+			esac
+			printf "%d:%d" $(stat -Lc "0x%t 0x%T" "$resume_dev") > $ROOT/sys/power/resume
+			if [ -n "$KOPT_resume_offset" ]; then
+				echo "$KOPT_resume_offset" > $ROOT/sys/power/resume_offset
+			fi
+		else
+			echo "resume: no hibernation support found"
+		fi
+	fi
+
+	if [ "$KOPT_overlaytmpfs" = "yes" ]; then
+		# Create mountpoints
+		mkdir -p /media/root-ro /media/root-rw $sysroot/media/root-ro \
+			$sysroot/media/root-rw
+		# Mount read-only underlying rootfs
+		rootflags="${KOPT_rootflags:+$KOPT_rootflags,}ro"
+		$MOCK mount ${KOPT_rootfstype:+-t $KOPT_rootfstype} -o $rootflags \
+			$KOPT_root /media/root-ro
+		# Mount writable overlay tmpfs
+		overlaytmpfsflags="mode=0755,${KOPT_overlaytmpfsflags:+$KOPT_overlaytmpfsflags,}rw"
+		$MOCK mount -t tmpfs -o $overlaytmpfsflags root-tmpfs /media/root-rw
+		# Create additional mountpoints and do the overlay mount
+		mkdir -p /media/root-rw/work /media/root-rw/root
+		$MOCK mount -t overlay -o \
+			lowerdir=/media/root-ro,upperdir=/media/root-rw/root,workdir=/media/root-rw/work \
+			overlayfs $sysroot
+	else
+		if [ "$rootfstype" = "zfs" ]; then
+			prepare_zfs_root
+		fi
+		$MOCK mount ${rootfstype:+-t} ${rootfstype} \
+			-o ${KOPT_rootflags:-ro} \
+			${KOPT_root#ZFS=} $sysroot
+	fi
+
+	eend $?
+
+	if [ -r "$sysroot/etc/fstab" ]; then
+		while read dev mnt fs mntopts chk; do
+			if [ "$mnt" = "/usr" ]; then
+				ebegin "Mounting /usr"
+				$MOCK modprobe -a $fs 2> /dev/null
+				$MOCK mount -t $fs -o $mntopts $dev $sysroot/usr
+				eend $?
+			fi
+		done < $sysroot/etc/fstab
+	fi
+
+	cat "$ROOT"/proc/mounts 2>/dev/null | while read DEV DIR TYPE OPTS ; do
+		if [ "$DIR" != "/" -a "$DIR" != "$sysroot" -a -d "$DIR" ]; then
+			mkdir -p $sysroot/$DIR
+			$MOCK mount -o move $DIR $sysroot/$DIR
+		fi
+	done
+	$MOCK sync
+	exec switch_root $switch_root_opts $sysroot $chart_init "$KOPT_init" $KOPT_init_args
+	echo "initramfs emergency recovery shell launched"
+	exec /bin/busybox sh
+fi
+
+if $do_networking; then
+	repoopts="-n"
+else
+	repoopts="-b $repofile"
+fi
+
+# locate boot media and mount it
+ebegin "Mounting boot media"
+$MOCK nlplug-findfs $cryptopts -p /sbin/mdev ${KOPT_debug_init:+-d} \
+	${KOPT_usbdelay:+-t $(( $KOPT_usbdelay * 1000 ))} \
+	${KOPT_uevent_buf_size:+-U $KOPT_uevent_buf_size} \
+	$repoopts -a "$ROOT"/tmp/apkovls
+eend $?
+
+# Setup network interfaces
+if $do_networking; then
+	configure_ip
+fi
+
+# early console?
+if [ "$SINGLEMODE" = "yes" ]; then
+	echo "Entering single mode. Type 'exit' to continue booting."
+	sh
+fi
+
+# mount tmpfs sysroot
+rootflags="mode=0755"
+if [ -n "$KOPT_root_size" ]; then
+	echo "WARNING: the boot option root_size is deprecated. Use rootflags instead"
+	rootflags="$rootflags,size=$KOPT_root_size"
+fi
+if [ -n "$KOPT_rootflags" ]; then
+	rootflags="$rootflags,$KOPT_rootflags"
+fi
+
+$MOCK mount -t tmpfs -o $rootflags tmpfs $sysroot
+
+if [ -z "$KOPT_apkovl" ]; then
+	# Not manually set, use the apkovl found by nlplug
+	if [ -e "$ROOT"/tmp/apkovls ]; then
+		ovl=$(head -n 1 "$ROOT"/tmp/apkovls)
+	fi
+elif is_url "$KOPT_apkovl"; then
+	# Fetch apkovl via network
+	MACHINE_UUID=$(cat "$ROOT"/sys/class/dmi/id/product_uuid 2>/dev/null)
+	url="$(echo "$KOPT_apkovl" | sed -e "s/{MAC}/$MAC_ADDRESS/" -e "s/{UUID}/$MACHINE_UUID/")"
+	ovl="/tmp/${url##*/}"
+	ovl="${ovl%%\?*}"
+	$MOCK wget -O "$ovl" "$url" || ovl=
+else
+	ovl="$KOPT_apkovl"
+fi
+
+# parse pkgs=pkg1,pkg2
+if [ -n "$KOPT_pkgs" ]; then
+	pkgs=$(echo "$KOPT_pkgs" | tr ',' ' ' )
+fi
+
+# load apkovl or set up a minimal system
+if [ -f "$ovl" ]; then
+	ebegin "Loading user settings from $ovl"
+	# create apk db and needed /dev/null and /tmp first
+	apk add --root $sysroot --initdb --quiet
+
+	unpack_apkovl "$ovl" $sysroot
+	eend $? $errstr || ovlfiles=
+	# hack, incase /root/.ssh was included in apkovl
+	[ -d "$sysroot/root" ] && chmod 700 "$sysroot/root"
+	pkgs="$pkgs $(cat $sysroot/etc/apk/world 2>/dev/null)"
+fi
+
+if [ -f "$sysroot/etc/.default_boot_services" -o ! -f "$ovl" ]; then
+	# add some boot services by default
+	rc_add devfs sysinit
+	rc_add dmesg sysinit
+	rc_add mdev sysinit
+	rc_add hwdrivers sysinit
+	rc_add modloop sysinit
+
+	rc_add modules boot
+	rc_add sysctl boot
+	rc_add hostname boot
+	rc_add bootmisc boot
+	rc_add syslog boot
+
+	rc_add mount-ro shutdown
+	rc_add killprocs shutdown
+	rc_add savecache shutdown
+
+	rc_add firstboot default
+
+	# add openssh
+	if [ -n "$KOPT_ssh_key" ]; then
+		pkgs="$pkgs openssh"
+		rc_add sshd default
+	fi
+
+	if want_tiny_cloud; then
+		pkgs="$pkgs tiny-cloud-alpine ifupdown-ng doas"
+		rc_add tiny-cloud-boot boot
+		rc_add tiny-cloud-early default
+		rc_add tiny-cloud-main default
+		rc_add tiny-cloud-final default
+	fi
+
+	rm -f "$sysroot/etc/.default_boot_services"
+fi
+
+if [ "$KOPT_splash" != "no" ]; then
+	echo "IMG_ALIGN=CM" > /tmp/fbsplash.cfg
+	for fbdev in /dev/fb[0-9]; do
+		[ -e "$fbdev" ] || break
+		num="${fbdev#/dev/fb}"
+		for img in /media/*/fbsplash$num.ppm; do
+			[ -e "$img" ] || break
+			config="${img%.*}.cfg"
+			[ -e "$config" ] || config=/tmp/fbsplash.cfg
+			fbsplash -s "$img" -d "$fbdev" -i "$config"
+			break
+		done
+	done
+	for fbsplash in /media/*/fbsplash.ppm; do
+		[ -e "$fbsplash" ] && break
+	done
+fi
+
+if [ -n "$fbsplash" ] && [ -e "$fbsplash" ]; then
+	ebegin "Starting bootsplash"
+	mkfifo $sysroot/$splashfile
+	config="${fbsplash%.*}.cfg"
+	[ -e "$config" ] || config=/tmp/fbsplash.cfg
+	setsid fbsplash -T 16 -s "$fbsplash" -i $config -f $sysroot/$splashfile &
+	eend 0
+else
+	KOPT_splash="no"
+fi
+
+if [ -f $sysroot/etc/fstab ]; then
+	has_fstab=1
+	fstab=$sysroot/etc/fstab
+
+	# let user override tmpfs size in fstab in apkovl
+	mountopts=$(awk '$2 == "/" && $3 == "tmpfs" { print $4 }' $sysroot/etc/fstab)
+	if [ -n "$mountopts" ]; then
+		$MOCK mount -o remount,$mountopts $sysroot
+	fi
+	# relocate mounts and adjust mount options
+	# this is so a generated /etc/apk/repositories will use correct
+	# mount dir
+	remount_fstab_entry "$sysroot"/etc/fstab
+elif [ -f "$ROOT"/etc/fstab ]; then
+	remount_fstab_entry "$ROOT"/etc/fstab
+fi
+
+# hack so we get openrc
+pkgs="$pkgs alpine-base"
+
+# copy keys so apk finds them. apk looks for stuff relative --root
+mkdir -p $sysroot/etc/apk/keys/
+$MOCK cp -a /etc/apk/keys $sysroot/etc/apk
+
+# generate apk repositories file. needs to be done after relocation
+find_boot_repositories > $repofile
+
+# silently fix apk arch in case the apkovl does not match
+if [ -r "$sysroot"/etc/apk/arch ]; then
+	apk_arch="$(apk --print-arch)"
+	if [ -n "$apk_arch" ]; then
+		echo "$apk_arch" > "$sysroot"/etc/apk/arch
+	fi
+fi
+
+# generate repo opts for apk
+for i in $(cat $repofile); do
+	repo_opt="$repo_opt --repository $i"
+done
+
+# install new root
+ebegin "Installing packages to root filesystem"
+
+if [ "$KOPT_chart" = yes ]; then
+	pkgs="$pkgs acct"
+fi
+
+# use swclock if no RTC is found
+if rtc_exists || [ "$(uname -m)" = "s390x" ]; then
+	rc_add hwclock boot
+else
+	rc_add swclock boot
+fi
+
+# enable support for modloop verification
+for _pubkey in "$ROOT"/var/cache/misc/*modloop*.SIGN.RSA.*.pub; do
+	# check only if the glob matched something
+	[ -f "$_pubkey" ] || continue
+
+	# then do it in one iteration anyway
+	mkdir -p "$sysroot"/var/cache/misc
+	cp "$ROOT"/var/cache/misc/*modloop*.SIGN.RSA.*.pub "$sysroot"/var/cache/misc
+	pkgs="$pkgs openssl"
+	break
+done
+
+apkflags="--initramfs-diskless-boot --progress"
+if [ -z "$MAC_ADDRESS" ]; then
+	apkflags="$apkflags --no-network"
+else
+	apkflags="$apkflags --update-cache"
+fi
+
+if [ "$KOPT_quiet" = yes ]; then
+	apkflags="$apkflags --quiet"
+fi
+
+if [ "$KOPT_keep_apk_new" != yes ]; then
+	apkflags="$apkflags --clean-protected"
+	[ -n "$ovlfiles" ] && apkflags="$apkflags --overlay-from-stdin"
+fi
+mkdir -p $sysroot/sys $sysroot/proc $sysroot/dev
+$MOCK mount -o bind /sys $sysroot/sys
+$MOCK mount -o bind /proc $sysroot/proc
+$MOCK mount -o bind /dev $sysroot/dev
+if [ -n "$ovlfiles" ]; then
+	apk add --root $sysroot $repo_opt $apkflags $pkgs <$ovlfiles
+else
+	apk add --root $sysroot $repo_opt $apkflags $pkgs
+fi
+$MOCK umount $sysroot/sys $sysroot/proc $sysroot/dev
+eend $?
+
+# unmount ovl mount if needed
+if [ -n "$ovl_unmount" ]; then
+	$MOCK umount $ovl_unmount 2>/dev/null
+fi
+
+# remount according default fstab from package
+if [ -z "$has_fstab" ] && [ -f "$sysroot"/etc/fstab ]; then
+	remount_fstab_entry "$sysroot"/etc/fstab
+fi
+
+# generate repositories if none exists. this needs to be done after relocation
+if ! [ -f "$sysroot"/etc/apk/repositories ]; then
+	find_boot_repositories > "$sysroot"/etc/apk/repositories
+fi
+
+# fix inittab if alternative console
+setup_inittab_console
+
+! [ -f "$sysroot"/etc/resolv.conf ] && [ -f /etc/resolv.conf ] && \
+	cp /etc/resolv.conf "$sysroot"/etc
+
+# setup bootchart for switch_root
+chart_init=""
+if [ "$KOPT_chart" = yes ]; then
+	/sbin/bootchartd stop-initfs "$sysroot"
+	chart_init="/sbin/bootchartd start-rootfs"
+fi
+
+if [ ! -x "${sysroot}${KOPT_init}" ]; then
+	[ "$KOPT_splash" != "no" ] && echo exit > $sysroot/$splashfile
+	echo "$KOPT_init not found in new root. Launching emergency recovery shell"
+	echo "Type exit to continue boot."
+	/bin/busybox sh
+fi
+
+# switch over to new root
+cat "$ROOT"/proc/mounts 2>/dev/null | while read DEV DIR TYPE OPTS ; do
+	if [ "$DIR" != "/" -a "$DIR" != "$sysroot" -a -d "$DIR" ]; then
+		mkdir -p $sysroot/$DIR
+		$MOCK mount -o move $DIR $sysroot/$DIR
+	fi
+done
+sync
+
+[ "$KOPT_splash" = "init" ] && echo exit > $sysroot/$splashfile
+echo ""
+exec switch_root $switch_root_opts $sysroot $chart_init "$KOPT_init" $KOPT_init_args
+
+[ "$KOPT_splash" != "no" ] && echo exit > $sysroot/$splashfile
+echo "initramfs emergency recovery shell launched"
+exec /bin/busybox sh
+reboot
\ No newline at end of file