#!/bin/ash
# This is the very first script invoked by the Linux kernel and is
# running out of the ram disk.  There are no fileysstems mounted.
# It is important to have a way to invoke a recovery shell in case
# the boot scripts are messed up, but also important to modify the
# PCRs if this happens to prevent the TPM disk keys from being revealed.

# First thing it is vital to mount the /dev and other system directories
mkdir /proc /sys /dev /tmp /boot /media 2>&- 1>&-
mount /dev
mount /proc
mount /sys

# Recovery shells will erase anything from here
mkdir -p /tmp/secret

# Setup our path
export PATH=/sbin:/bin

# Now it is safe to print a banner
if [ -r /etc/motd ]; then
	cat /etc/motd
fi

# Load the date from the hardware clock, setting it in local time
hwclock -l -s

# Read the system configuration parameters
. /etc/functions
. /etc/config

if [ ! -x "$CONFIG_BOOTSCRIPT" ]; then
	recovery 'Boot script missing?  Entering recovery shell'
	# just in case...
	tpm extend -ix 4 recovery
	exec /bin/ash
fi

# Give the user a second to enter a recovery shell
read \
	-t "1" \
	-p "Press 'r' for recovery shell: " \
	-n 1 \
	boot_option
echo

if [ "$boot_option" = "r" ]; then
	# Start an interactive shell
	recovery 'User requested recovery shell'
	# just in case...
	tpm extend -ix 4 recovery
	exec /bin/ash
fi

echo '***** Normal boot'
exec "$CONFIG_BOOTSCRIPT"

# We should never reach here, but just in case...
recovery 'Boot script failure?  Entering recovery shell'
# belts and suspenders, just in case...
tpm extend -ix 4 recovery
exec /bin/ash