#!/bin/sh
# This script is run once when the system first boots.  Its sole
# purpose is to create /etc/default/sysconf (the overall system
# configuration file) and other files derived from this.
#
# The script runs immediately after S10checkroot.sh - this is the
# point at which the rootfs will be mounted rw even if the kernel
# booted with it ro.
#
# rm or mv the file to run this again.  If this is done the
# following configuration files will be rewritten:
#
# /etc/default/sysconf
# /etc/hostname
# /etc/defaultdomain
# /etc/network/interfaces
# /etc/resolv.conf
#
# /etc/default/functions contains useful utility functions - it's
# in a separate file so that it can be loaded by any script
. /etc/default/functions
#
config valid && test "$1" != reload && exit 0
#
# Utility to deal with absence of DNS configuration
echodns(){
	local dns
	if test $# -gt 0
	then
		for dns in "$@"
		do
			echo "nameserver $dns"
		done
	fi
}
#
# The SysConf device must exist in /dev at this point for this script
# to work.
#
# It is important not to hard-wire the name of the device because of
# the posibility of changing the flash partition layout.
#
# The block device is used here because at present udev does not
# show the character devices
sysdev=
config valid || sysdev="$(mtblockdev SysConf)"
if test -n "$sysdev" -a -b "$sysdev"
then
	# Read the defined part of SysConf into /etc/default/sysconf.
	# SysConf has lines of two forms:
	#
	#  [section]
	#  name=value
	#
	# In practice SysConf also contains other stuff, use the command:
	#
	#  devio '<</dev/mtd1;cpb'
	#
	# to examine the current settings.  The badly formatted stuff
	# is removed (to be exact, the sed script selects only lines
	# which match one of the two above).  The lan interface, which
	# defaults to ixp0, is changed to the correct value for openslug,
	# eth0.  The bootproto, which LinkSys sets to static in manufacturing,
	# is reset to dhcp if the IP is still the original (192.168.1.77)
	devio "<<$sysdev" cpb fb1,10 | sed -n '/^\[[^][]*\]$/p;
		s/^lan_interface=ixp0$/lan_interface=eth0/;
		/^ip_addr=192\.168\.1\.77$/,/^bootproto/s/^bootproto=static$/bootproto=dhcp/;
		/^[-a-zA-Z0-9_][-a-zA-Z0-9_]*=/p' >/etc/default/sysconf
	#
	# The SysConf must have a hardware id, if it doesn't it has
	# probably been erased or never set in the first place and the
	# hardware id is retrieved from the RedBoot partition.  This is
	# the only thing which cannot be defaulted.
fi
#
# Error recovery: no SysConf or invalid SysConf.  Make a new one from the
# RedBoot hardware ID information.
# NOTE: this block of code overwrites the shell script arguments.
config valid || {
	reddev="$(mtblockdev RedBoot)"
	initmac=
	if test -n "$reddev" -a -b "$reddev"
	then
		# The hardware id starts 80 bytes before the end of the
		# block, the block ends (or should end) with the signature
		# <4 bytes> sErCoMm <bytes> sErCoMm.  Note that devio 'pf'
		# empties the stack.
		set -- $(devio "<<$reddev" '
			<= $80-
			.= @
			pf %02X
			A= 5
			$( 1
				A= @,A1-
				pf :%02X
			$) A
			pn
			<=f4+;cp7;pn
			<=$7-;cp7;pn')
		if test $# -eq 3 -a "$2" = sErCoMm -a "$3" = sErCoMm
		then
			initmac="$1"
		fi
	fi
	#
	# APEX: may need extra code to set initmac here.
	#
	if test -n "$initmac"
	then
		#
		# Generate a complete /etc/default/sysconf based on just
		# one number ;-)
		{	echo '[network]'
			echo "hw_addr=$initmac"
		} >/etc/default/sysconf
		#
		# See /etc/default/functions (the config function) for
		# the derivation of the rest of the information.
	fi
}
#
# The config function will now return the correct values - even if sysconf
# is still missing.  'config valid' says if valid configuration information
# is available.
#
# Set up the 'standard' files in the root file system (these couldn't be set
# up before because they depend on stuff which RedBoot puts into SysConf from
# the ID info on the specific machine - in particular the hardware address of
# eth0, which must be the one assigned for *this* box!)
#
# HOSTNAME: defaults to LGK<mac> i.e. something derived from
# the ethernet hardware.  LinkSys documentation explains how
# to determine this.  Set by the user in linksys setup software.
# DOMAINNAME: LinkSys puts this in w_d_name.
test -n "$(config host)" && config host >/etc/hostname
domain="$(config domain)"
test -n "$domain" && echo "$domain" >/etc/defaultdomain
#
# Ethernet information.  This goes into /etc/network/interfaces,
# however this is only used for static setup (and this is not
# the default).  With dhcp the openslug udhcp script,
# /etc/udhcpc.d/50default, loads the values from sysconf.  The
# lan_interface config value must exist for the file to be
# overwritten here.
iface="$(config iface)"
if test -n "$iface"
then
	boot="$(config boot)"
	# Only dhcp and static are supported at present - bootp
	# support requires installation of appropriate packages
	# dhcp is the fail-safe
	case "$boot" in
	dhcp|static) ;;
	*)    boot=dhcp;;
	esac
	#
	mac="$(config mac)"
	ip="$(config ip)"
	netmask="$(config netmask)"
	gateway="$(config gateway)"
	{
		echo "# /etc/network/interfaces"
		echo "# configuration file for ifup(8), ifdown(8)"
		echo "#"
		echo "# The loopback interface"
		echo "auto lo"
		echo "iface lo inet loopback"
		echo "#"
		echo "# The NSLU2 built-in ethernet"
		echo "auto $iface"
		echo "# Automatically generated from /etc/default/sysconf"
		if config valid
		then
			echo "# The pre-up option must always be supplied, regardless"
			echo "# of configuration, to set the hardware correctly."
			echo "# Severe network problems may result if this option is"
			echo "# removed."
			c=
		else
			echo "# WARNING: improperly configured network interface."
			echo "# WARNING: the pre-up line must be corrected or severe"
			echo "# WARNING: network problems may result."
			c='#'
			mac='<WARNING: unknown hardware address>'
		fi
		echo "iface $iface inet $boot"
		echo "${c}	pre-up ifconfig $iface hw ether $mac"
		# The following are ignored for DHCP but are harmless
		test -n "$ip"      && echo "	address $ip"
		test -n "$netmask" && echo "	netmask $netmask"
		test -n "$gateway" && echo "	gateway $gateway"
	} >/etc/network/interfaces
fi
#
# The DNS server information gives up to three nameservers, but this
# currently only binds in the first.
{
	test -n "$domain" && echo "search $domain"
	echodns $(config dns) $(config dns1) $(config dns2)
} >/etc/resolv.conf
#
# Invalid config must be handled, do this by hacking /etc/motd.
if config valid
then
	echo "Host name:           $(config host)"
	echo "Host ID:             $mac"
	echo "Network boot method: $boot"
	case "$boot" in
	static) echo "Host IP address:     $ip";;
	esac
	echo "Use 'turnup init' to reset the configuration"
	echo "Use 'turnup disk|nfs -i <device> options to initialise a non-flash root"
	echo "Use 'turnup help' for more information"
else
	echo "+=====================================================================+"
	echo "|                   +-----------------------+                         |"
	echo "|                   | INITIALISATION FAILED |                         |"
	echo "|                   +-----------------------+                         |"
	echo "|                                                                     |"
	echo "| This machine has been booted with a temporary ethernet id           |"
	echo "| The initialisation failed because the machine id was not available  |"
	echo "| within the flash memory of the NSLU2.  You must run:                |"
	echo "|                                                                     |"
	echo "|       turnup init                                                   |"
	echo "|                                                                     |"
	echo "| To correct this problem.  Severe network problems may occur if this |"
	echo "| is not done.                                                        |"
	echo "+=====================================================================+"
fi >/etc/motd

exit 0