#!/bin/bash
# Copyright (c) 2004-2005 Gentoo Foundation
# Distributed under the terms of the GNU General Public License v2

# We will be loaded after conf.d/rc and conf.d/net so we can set a default
# here.
RC_AUTO_INTERFACE="${RC_AUTO_INTERFACE:-no}"

netdir="/var/lib/net-scripts"
statedir="${netdir}/state"

# Contributed by Roy Marples (uberlord@gentoo.org)

# char* interface_device(char *iface)
#
# Gets the base device of the interface
# Can handle eth0:1 and eth0.1
# Which returns eth0 in this case
interface_device() {
	local dev="${1%%.*}"
	[[ ${dev} == "$1" ]] && dev="${1%%:*}"
	echo "${dev}"
}

# char* interface_type(char* iface)
#
# Returns the base type of the interface
# eth, ippp, etc
interface_type() {
	echo "${1%%[0-9]*}"
}

# void save_state(char *interface)
#
# Saves state information regarding the interface
save_state() {
	local iface="$1"
	local d="${statedir}/${iface}"

	[[ ! -d ${d} ]] && mkdir -m 0755 -p "${d}"
	cp -a /etc/resolv.conf /etc/ntp.conf /etc/yp.conf "${d}" 2>/dev/null
}

# void remove_state(char *interface)
#
# Removes state information regarding the interface
remove_state() {
	local d="${statedir}/$1"

	[[ -d ${d} ]] && rm -Rf "${d}" 2>/dev/null
	[[ ! ${2:-true} ]] && mkdir -m 0755 -p "${d}"
}

# void apply_state(char *interface)
#
# Apply's state information about the interface to the system
# If the files in the state dir are not links back to etc then
# we create them if RC_AUTO_INTERFACE="yes"
#
apply_state() {
	local iface="$1"

	if [[ -z ${iface} ]]; then
		iface=$( select_best_interface )
		[[ -z ${iface} ]] && return
	fi

	local d="${statedir}/${iface}"
	if [[ -d ${d} ]]; then
		local files=$( ls "${d}" )
		if [[ -n ${files} ]] ; then
			if [[ ${RC_AUTO_INTERFACE} == "yes" ]]; then
				cp -aR "${d}"/* "${netdir}"
				local file 
				for file in ${files} ; do
					# Skip .sv files
					[[ ${file} == *".sv" ]] && contine
					local link=$( readlink "/etc/${file}" 2>/dev/null )
					if [[ ${link} != "${netdir}/${file}" ]]; then
						[[ -e "/etc/${file}" ]] && rm -f "/etc/${file}"
						ln -snf "${netdir}/${file}" "/etc/${file}"
					fi
				done
			else
				cp -ar "${d}"/* /etc
			fi
		fi
	fi

	[[ ${RC_AUTO_INTERFACE} == "yes" ]] && merge_configs
}

# char* order_interfaces(bool require_gateway)
#
# Lists the interfaces in route metric order that we have configured
# (ie a state dir exists)
# require_gateway defaults to false
order_interfaces() {
	local ifaces
	
	if [[ ${1:-false} == "true" ]]; then
		ifaces=$(awk '$2!="Gateway" { print $7, $1 }' /proc/net/route \
		| sort -n | cut -d' ' -f2 | uniq)
	else
		ifaces=$(awk '$2=="00000000" { print $7, $1 }' /proc/net/route \
		| sort -n | cut -d' ' -f2 )
	fi

	# Append lo if it's up
	if grep -q "^lo[ \t]*" /proc/net/route ; then
		ifaces="${ifaces} lo"
	fi
	
	local i order
	for i in ${ifaces}; do
		[[ -d "${statedir}/${i}" ]] && order="${order}${i} "
	done

	echo "${order}"
}

# void merge_resolv()
#
# Merges the resolv.conf info from active interfaces
merge_resolv() {
	local -a ifaces=( $(order_interfaces) )
	local i j f

	# We only work for ifaces with a resolv.conf
	j=${#ifaces[@]}
	for (( i=0; i<j; i++ )); do
		[[ ! -e "${statedir}/${ifaces[i]}/resolv.conf" ]] && unset ifaces[i]
	done
	ifaces=( "${ifaces[@]}" )
	
	# No point merging unless there are two or more interfaces
	[[ ${#ifaces[@]} -lt 2 ]] && return

	veinfo "Merging resolv.conf from interfaces ${ifaces[@]}"
	
	local -a search srvs opts sortlist
	j=0
	for (( i=0; i<${#ifaces[@]}; i++ )); do
		f="${statedir}/${ifaces[i]}/resolv.conf"
		srvs[i]=$( sed -n -e 's/^[ \t]*nameserver[ \t]*\([^#]*\).*/\1/p' "${f}" \
			| sed 2q )
		
		search[i]=$( sed -n -e 's/^[ \t]*\(domain\|search\)[ \t]*\([^#]*\).*/\2/p' \
			"${f}" | sed -e '$!d' )

		opts[i]=$( sed -n -e 's/^[ \t]*options[ \t]*\([^#]*\).*/\1#/p;' "${f}" | xargs )
		sortlist[i]=$( sed -n -e 's/^[ \t]*sortlist[ \t]*\([^#]*\).*/\1/p' "${f}" )
		
		if [[ -z ${srvs[i]} && -z ${opts[i]} && -z ${sortlist[i]} ]]; then
			unset srvs[i]
			unset search[i]
			unset opts[i]
			unset sortlist[i]
			continue
		fi
		
		# No point in handling more than 3 interfaces due to libc limits
		(( j++ ))
		[[ ${j} -gt 2 ]] && break
	done
	srvs=( "${srvs[@]}" )
	search=( ${search[@]} )
	opts=( "${opts[@]}" )
	sortlist=( ${sortlist[@]} )

	local new_srvs
	j=0
	# Add interface primary nameservers
	for (( i=0;i<${#srvs[@]}; i++ )); do
		local -a n=( ${srvs[i]} )
		if [[ " ${new_srvs} " != *" ${n[0]} "* ]]; then
			new_srvs="${new_srvs} ${n[0]}"
			# libc can only handle 3 name servers
			(( j++ ))
			[[ ${j} -gt 2 ]] && break
		fi
	done

	# Add interface secondary nameservers
	if [[ ${j} -lt 3 ]]; then
		for (( i=0;i<${#srvs[@]}; i++ )); do
			local -a n=( ${srvs[i]} )
			[[ -z ${n[1]} ]] && continue
			if [[ " ${new_srvs} " != *" ${n[1]} "* ]]; then
				new_srvs="${new_srvs} ${n[1]}"
				# libc can only handle 3 name servers
				(( j++ ))
				[[ ${j} -gt 2 ]] && break
			fi
		done
	fi

	local new_search n_search=0
	for i in ${search[@]}; do
		if [[ " ${new_search} " != *" ${i} "* ]]; then
			new_search="${new_search} ${i}"
			# libc limits us to 6 search domains
			(( n_search++ ))
			[[ ${n_search} -gt 5 ]] && break
		fi
	done

	local new_opts
	for i in "${opts[@]}"; do
		new_opts="${new_opts}#${i}"
	done

	# Remove duplicate options
	new_opts=$(
		echo -e "${new_opts//\#/\n}" \
		| sort -u | sed -e 's/^/#/g' | xargs
	)

	local new_sortlist n_sortlist=0
	for i in ${sortlist[@]}; do
		if [[ " ${new_sortlist} " != *" ${i} "* ]]; then
			new_sortlist="${new_sortlist} ${i}"
			# libc limits us to 10 items
			(( n_sortlist++ ))
			[[ ${n_sortlist} -gt 9 ]] && break
		fi
	done

	# Now we create a new resolv.conf to use
	local f="${netdir}/resolv.conf.$$"
	echo "# Generated by net-scripts from interfaces ${ifaces[@]}" > "${f}"
	chmod 644 "${f}"
	for i in ${new_srvs[@]}; do
		echo "nameserver ${i}" >> "${f}"
	done
	if [[ -n ${new_search} ]]; then
		if [[ ${n_search} == "1" ]]; then
			echo "domain${new_search}" >> "${f}"
		else
			echo "search${new_search}" >> "${f}"
		fi
	fi

	[[ -n ${new_sortlist} ]] && echo "sortlist${new_sortlist}" >> "${f}"
	
	# We seperated the options out using # in our sed call above
	# so we set IFS here. If you do any spliting futher down in this function
	# then you will need to reset IFS.
	local IFS="#"
	for i in ${new_opts}; do
		[[ -n ${i# } ]] && echo "options ${i# }" >> "${f}"
	done
	
	mv "${f}" "${netdir}/resolv.conf"
}


# void merge_ntp()
#
# Merges the ntp.conf info from active interfaces
merge_ntp() {
	local -a ifaces=( $(order_interfaces) )
	local i j f

	# We only work for ifaces with a ntp.conf
	j=${#ifaces[@]}
	for (( i=0; i<j; i++ )); do
		[[ ! -e "${statedir}/${ifaces[i]}/ntp.conf" ]] && unset ifaces[i]
	done
	ifaces=( "${ifaces[@]}" )
	
	# No point merging unless there are two or more interfaces
	[[ ${#ifaces[@]} -lt 2 ]] && return

	veinfo "Merging ntp.conf from interfaces ${ifaces[@]}"
	
	local srvs
	for (( i=0; i<${#ifaces[@]}; i++ )); do
		f="${statedir}/${ifaces[i]}/ntp.conf"
		srvs="${srvs} $( sed -n -e 's/^[ \t]*server[ \t]*\([^#]\)/\1/p' "${f}" )"
	done

	# ntp does it's own preference list, so we just remove duplicates
    sort_unique() {
		set -- " ${@/%/\n}"
		echo -e "$@" | sort -u
	}

	srvs=$( sort_unique ${srvs} )

	f="${netdir}/ntp.conf.$$"
    echo "# Generated by net-scripts for interfaces ${ifaces[@]}" > "${f}"
    chmod 644 "${f}"

    echo "restrict default noquery notrust nomodify" >> "${f}"
    echo "restrict 127.0.0.1" >> "${f}"

    for i in ${srvs}; do
        echo "restrict ${i} nomodify notrap noquery" >> "${f}"
        echo "server ${i}" >> "${f}"
    done

    echo "driftfile /var/lib/ntp/ntp.drift" >> "${f}"
    echo "logfile /var/log/ntp.log" >> "${f}"

    mv "${f}" "${netdir}/ntp.conf"
}

# void merge_configs()
#
# Merge config files together
merge_configs() {
	merge_resolv
	merge_ntp
}

# char* select_best_interface()
#
# Selects the best interface to apply state information to
# This is currently based on routing metrics
select_best_interface() {
	local -a ifs=( $(order_interfaces true) )

	# Move lo to the back of the pecking order of it's active
	local x=" ${ifs[@]} "
	[[ ${x// lo / } != "${x}" ]] && ifs=( ${x// lo / } lo )

	local iface
	for iface in ${ifs[@]} ; do
		if [[ -e "${statedir}/${iface}/resolv.conf" ]]; then
			echo "${iface}"
			return 0
		fi
	done

	echo "${ifs[0]}"
}

# int calculate_metric(char *interface)
#
# Calculates the best metric for the interface
# The Linux kernel does not use this at the moment, but we use it so that
# default routes remain and we can work out the "best" interface
calculate_metric() {
	local iface="$1" exclude='$1!="Iface" && $1!="lo"'

	# Have we already got a metric?
	local m=$( awk '$1=="'${iface}'" && $2=="00000000" { print $7 }' \
		/proc/net/route )
	if [[ -n ${m} ]]; then
		echo "${m}"
		return 0
	fi

	local itype=$( interface_type "${iface}" ) x i

	# If we're not a wireless device then exclude wireless from the
	# routing table so we stay < 1000
	if [[ -e /proc/net/wireless ]]; then
		if ! grep -q "^[ \t]*${iface}:[ \t]" /proc/net/wireless ; then
			local i=$( sed -n -e 's/^[ \t]*\(.*\):.*/\1/p' /proc/net/wireless )
			for x in ${i} ; do
				exclude="${exclude} && "'$1'"!=\"${x}\""
			done
		fi
	fi

	# Exclude ppp and ippp as well
	local ix="ppp|ippp"
	[[ ${itype} == "ppp" ]] && ix="ippp"
	[[ ${itype} == "ippp" ]] && ix="ppp"
	i=$( sed -n -e 's/^[ ]*\('${ix}'[0-9]*\):.*$/\1/p' /proc/net/dev )
	for x in ${i} ; do
		exclude="${exclude} && "'$1'"!=\"${x}\""
	done

	local m=$( awk "${exclude} { print "'$7'" }" /proc/net/route \
		| sort -rn | head -n 1 | cut -d' ' -f2 )
	m="${m:--1}"
	(( m ++ ))

	# If we're a wireless device then add 1000 so that wired interfaces take preference
	if [[ -e /proc/net/wireless ]]; then
		grep -q "^[ \t]*${iface}:[ \t]" /proc/net/wireless && (( m+= 1000 ))
	fi

	# If we're a ppp device then we add 2000 for ISDN, otherwise 3000
	[[ ${itype} == "ippp" ]] && (( m+= 2000 ))
	[[ ${itype} == "ppp" ]] && (( m+= 3000 ))

	echo "${m}"
}

# int netmask2cidr(char *netmask)
#
# Returns the CIDR of a given netmask
netmask2cidr() {
	local binary="" i bin

	for i in ${1//./ }; do
		bin=""
		while [[ ${i} != "0" ]]; do
			bin=$[${i}%2]${bin}
			(( i=i>>1 ))
		done
		binary="${binary}${bin}"
	done
	binary="${binary%%0*}"
	echo "${#binary}"
}

# char* netmask2cidr(int cidr)
#
# Returns the netmask of a given CIDR
cidr2netmask() {
	local cidr="$1" netmask="" done=0 i sum=0 cur=128
	local octets frac

	(( octets=cidr/8 ))
	(( frac=cidr%8 ))
	while [[ octets -gt 0 ]]; do
		netmask="${netmask}.255"
		(( octets-- ))
		(( done++ ))
	done

	if [[ ${done} -lt 4 ]]; then
		for (( i=0; i<${frac}; i++ )); do
			(( sum+=cur ))
			(( cur/=2 ))
		done
		netmask="${netmask}.${sum}"
		(( done++ ))

		while [[ ${done} -lt 4 ]]; do
			netmask="${netmask}.0"
			(( done++ ))
		done
	fi

	echo "${netmask:1}"
}

# char* ip_network(char *ip, char *netmask)
#
# Returns the network of the ip address
# ip can be 192.168.0.51/24
# or
# ip can be 192.168.0.51 and netmask is 255.255.255.0
ip_network() {
	local ip="$1" mask="$2" i network x

	# We only work for IPv4 addresses
	[[ ${ip} != *.*.*.* ]] && return
	
	# If we didn't get parameter 2 then assume we have a CIDR
	if [[ -z ${mask} ]]; then
		mask="${ip##*/}"
		[[ -z ${mask} || ${mask} == ${ip} ]] && return 1
		mask=$( cidr2netmask "${mask}" )
		ip="${ip%%/*}"
	fi

	ip=( ${ip//./ } )
	mask=( ${mask//./ } )

	for (( i=0; i<4; i++ )); do
		(( x=ip[i] & mask[i] ))
		network="${network}${x}"
		[[ ${i} -lt 3 ]] && network="${network}."
	done

	echo "${network}"
}

# bool clean_pidfile(char *file)
#
# Removes the given pidfile if the process is not running
# Returns 1 if the process is still running otherwise 0
clean_pidfile() {
	local pidfile="$1"

	[[ ! -f ${pidfile} ]] && return 0
	local pid=$( < "${pidfile}" )

	if [[ -n ${pid} ]]; then
		local cmd="${pidfile##*/}"
		cmd="${cmd%%-*}"
		ps -p "${pid}" 2>/dev/null | grep -q "${cmd}" && return 1
	fi

	rm -f "${pidfile}"
	return 0
}

# bool process_finished(int pid, char* cmd)
#
# We wait for 10 seconds until the command ${cmd}
# stops running on the process ${pid}
process_finished() {
	local i pid="$1" cmd="$2" secs="${3:-9}"

	for (( i=0; i<secs; i++ )); do
		ps -p "${pid}" 2>/dev/null | grep -q "${cmd}" || return 0
		sleep 1
	done

	return 1
}

# bool is_function(char* name)
#
# Returns 0 if the given name is a shell function, otherwise 1
is_function() {
	[[ -z $1 ]] && return 1
	[[ $(type -t "$1") == "function" ]]
}

# void function_wrap(char* source, char* target)
#
# wraps function calls - for example function_wrap(this, that)
# maps function names this_* to that_*
function_wrap() {
	local i

	is_function "${2}_depend" && return

	for i in $( typeset -f | grep -o '^'"${1}"'_[^ ]*' ); do
		eval "${2}${i#${1}}() { ${i} \"\$@\"; }"
	done
}

# char[] * expand_parameters(char *cmd)
#
# Returns an array after expanding parameters. For example
# "192.168.{1..3}.{1..3}/24 brd +"
# will return
# "192.168.1.1/24 brd +"
# "192.168.1.2/24 brd +"
# "192.168.1.3/24 brd +"
# "192.168.2.1/24 brd +"
# "192.168.2.2/24 brd +"
# "192.168.2.3/24 brd +"
# "192.168.3.1/24 brd +"
# "192.168.3.2/24 brd +"
# "192.168.3.3/24 brd +"
expand_parameters() {
	local x="$( eval echo ${@// /_} )"
	local -a a=( ${x} )

	a=( "${a[@]/#/\"}" )
	a=( "${a[@]/%/\"}" )
	echo "${a[*]//_/ }"
}

# void configure_variables(char *interface, char *option1, [char *option2])
#
# Maps configuration options from <variable>_<option> to <variable>_<iface>
# option2 takes precedence over option1
configure_variables() {
	local iface="$1" option1="$2" option2="$3"

	local mod func x i
	local -a ivars ovars1 ovars2
	local ifvar=$( bash_variable "${iface}" )

	for mod in ${MODULES[@]}; do
		is_function ${mod}_variables || continue
		for v in $(${mod}_variables) ; do
			x=""
			[[ -n ${option2} ]] && eval x=( \"\$\{${v}_${option2}\[@\]\}\" )
			[[ -z ${x} ]] && eval x=( \"\$\{${v}_${option1}\[@\]\}\" )
			[[ -n ${x} ]] && eval "${v}_${ifvar}=( "\"\$\{x\[@\]\}\"" )"
		done
	done

	return 0
}

# Provide a wrapper for hostname if it's not available
if [[ -z $(type -p hostname) ]]; then
	hostname() {
		# Linux and *BSD seem to differ
		local kernel="kern" ctl="hostname"
		[[ $(uname) == "Linux" ]] && kernel="kernel"
		
		if [[ $1 == "-y" || $1 == "--yp" || $1 == "nis" ]]; then
			ctl="domainname"
			shift
		fi
		
		if [[ -n $1 ]]; then
			sysctl -q -w "${kernel}.${ctl}=$1"
		else
			sysctl -n "${kernel}.${ctl}"
		fi
	}
fi

# vim:ts=4