#
# Shorewall 5.0 -- /usr/share/shorewall/lib.core
#
#     (c) 1999-2015 - Tom Eastep (teastep@shorewall.net)
#
#	Complete documentation is available at http://shorewall.net
#
#       This program is part of Shorewall.
#
#	This program is free software; you can redistribute it and/or modify
#	it under the terms of the GNU General Public License as published by the
#       Free Software Foundation, either version 2 of the license or, at your
#       option, any later version.
#
#	This program is distributed in the hope that it will be useful,
#	but WITHOUT ANY WARRANTY; without even the implied warranty of
#	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
#	GNU General Public License for more details.
#
#	You should have received a copy of the GNU General Public License
#	along with this program; if not, see <http://www.gnu.org/licenses/>.
#
# This library contains the code common to all Shorewall components except the
# generated scripts.
#

SHOREWALL_LIBVERSION=50100

#
# Fatal Error
#
fatal_error() # $@ = Message
{
    echo "   ERROR: $@" >&2
    exit 2
}

setup_product_environment() { # $1 = if non-empty, source shorewallrc again now that we have the correct product
    g_basedir=${SHAREDIR}/shorewall

    g_sharedir="$SHAREDIR"/$PRODUCT
    g_confdir="$CONFDIR"/$PRODUCT

    case $PRODUCT in
	shorewall)
	    g_product="Shorewall"
	    g_family=4
	    g_tool=iptables
	    g_lite=
	    ;;
	shorewall6)
	    g_product="Shorewall6"
	    g_family=6
	    g_tool=ip6tables
	    g_lite=
	    ;;
	shorewall-lite)
	    g_product="Shorewall Lite"
	    g_family=4
	    g_tool=iptables
	    g_lite=Yes
	    ;;
	shorewall6-lite)
	    g_product="Shorewall6 Lite"
	    g_family=6
	    g_tool=ip6tables
	    g_lite=Yes
	    ;;
	*)
	    fatal_error "Unknown PRODUCT ($PRODUCT)"
	    ;;
    esac

    [ -f ${SHAREDIR}/${PRODUCT}/version ] || fatal_error "$g_product does not appear to be installed on this system"
    #
    # We need to do this again, now that we have the correct product
    #
    [ -n "$1" ] && . ${g_basedir}/shorewallrc

    if [ -z "${VARLIB}" ]; then
	VARLIB=${VARDIR}
	VARDIR=${VARLIB}/${PRODUCT}
    elif [ -z "${VARDIR}" ]; then
	VARDIR="${VARLIB}/${PRODUCT}"
    fi
}

set_default_product() {
    case $(basename $0) in
	shorewall6)
	    PRODUCT=shorewall6
	    ;;
	shorewall4)
	    PRODUCT=shorewall
	    ;;
	shorewall-lite)
	    PRODUCT=shorewall-lite
	    ;;
	shorewall6-lite)
	    PRODUCT=shorewall6-lite
	    ;;
	*)
	    if [ -f ${g_basedir}/version ]; then
		PRODUCT=shorewall
	    elif [ -f ${SHAREDIR}/shorewall-lite/version ]; then
		PRODUCT=shorewall-lite
	    elif [ -f ${SHAREDIR}/shorewall6-lite/version ]; then
		PRODUCT=shorewall6-lite
	    else
		fatal_error "No Shorewall firewall product is installed"
	    fi
	    ;;
    esac
}

# Not configured Error
#
not_configured_error() # $@ = Message
{
    echo "   ERROR: $@" >&2
    exit 6
}

#
# Conditionally produce message
#
progress_message() # $* = Message
{
    local timestamp
    timestamp=

    if [ $VERBOSITY -gt 1 ]; then
	[ -n "$g_timestamp" ] && timestamp="$(date +%H:%M:%S) "
	echo "${timestamp}$@"
    fi
}

progress_message2() # $* = Message
{
    local timestamp
    timestamp=

    if [ $VERBOSITY -gt 0 ]; then
	[ -n "$g_timestamp" ] && timestamp="$(date +%H:%M:%S) "
	echo "${timestamp}$@"
    fi
}

progress_message3() # $* = Message
{
    local timestamp
    timestamp=

    if [ $VERBOSITY -ge 0 ]; then
	[ -n "$g_timestamp" ] && timestamp="$(date +%H:%M:%S) "
	echo "${timestamp}$@"
    fi
}

#
# Undo the effect of 'separate_list()'
#
combine_list()
{
    local f
    local o
    o=

    for f in $* ; do
        o="${o:+$o,}$f"
    done

    echo $o
}

#
# Validate an IP address
#
valid_address() {
    local x
    local y
    local ifs
    ifs=$IFS

    IFS=.

    for x in $1; do
	case $x in
	    [0-9]|[0-9][0-9]|[1-2][0-9][0-9])
		[ $x -lt 256 ] || { IFS=$ifs; return 2; }
                ;;
	    *)
	        IFS=$ifs
		return 2
		;;
	esac
    done

    IFS=$ifs

    return 0
}

#
# Miserable Hack to work around broken BusyBox ash in OpenWRT
#
addr_comp() {
    test $(bc <<EOF
$1 > $2
EOF
) -eq 1

}

#
# Enumerate the members of an IP range -- When using a shell supporting only
# 32-bit signed arithmetic, the range cannot span 128.0.0.0.
#
# Comes in two flavors:
#
# ip_range() - produces a mimimal list of network/host addresses that spans
#              the range.
#
# ip_range_explicit() - explicitly enumerates the range.
#
ip_range() {
    local first
    local last
    local l
    local x
    local y
    local z
    local vlsm

    case $1 in
	!*)
	    #
	    # Let iptables complain if it's a range
	    #
	    echo $1
	    return
	    ;;
	[0-9]*.*.*.*-*.*.*.*)
            ;;
	*)
	    echo $1
	    return
	    ;;
    esac

    first=$(decodeaddr ${1%-*})
    last=$(decodeaddr ${1#*-})

    if addr_comp $first $last; then
	fatal_error "Invalid IP address range: $1"
    fi

    l=$(( $last + 1 ))

    while addr_comp $l $first; do
	vlsm=
	x=31
	y=2
	z=1

	while [ $(( $first % $y )) -eq 0 ] && ! addr_comp $(( $first + $y )) $l; do
	    vlsm=/$x
	    x=$(( $x - 1 ))
	    z=$y
	    y=$(( $y * 2 ))
	done

	echo $(encodeaddr $first)$vlsm
	first=$(($first + $z))
    done
}

ip_range_explicit() {
    local first
    local last

    case $1 in
    [0-9]*.*.*.*-*.*.*.*)
	;;
    *)
	echo $1
	return
	;;
    esac

    first=$(decodeaddr ${1%-*})
    last=$(decodeaddr ${1#*-})

    if addr_comp $first $last; then
	fatal_error "Invalid IP address range: $1"
    fi

    while ! addr_comp $first $last; do
	echo $(encodeaddr $first)
	first=$(($first + 1))
    done
}

[ -z "$LEFTSHIFT" ] && . ${g_basedir}/lib.common

#
# Netmask to VLSM
#
ip_vlsm() {
    local mask
    mask=$(decodeaddr $1)
    local vlsm
    vlsm=0
    local x
    x=$(( 128 << 24 )) # 0x80000000

    while [ $(( $x & $mask )) -ne 0 ]; do
	[ $mask -eq $x ] && mask=0 || mask=$(( $mask $LEFTSHIFT 1 )) # Not all shells shift 0x80000000 left properly.
	vlsm=$(($vlsm + 1))
    done

    if [ $(( $mask & 2147483647 )) -ne 0 ]; then # 2147483647 = 0x7fffffff
	echo "Invalid net mask: $1" >&2
    else
	echo $vlsm
    fi
}

#
# Set default config path
#
ensure_config_path() {
    local F
    F=${g_sharedir}/configpath
    if [ -z "$CONFIG_PATH" ]; then
	[ -f $F ] || { echo "   ERROR: $F does not exist"; exit 2; }
	. $F
    fi

    if [ -n "$g_shorewalldir" ]; then
	[ "${CONFIG_PATH%%:*}" = "$g_shorewalldir" ] || CONFIG_PATH=$g_shorewalldir:$CONFIG_PATH
    fi
}

#
# Get fully-qualified name of file
#
resolve_file() # $1 = file name
{
    local pwd
    pwd=$PWD

    case $1 in
	/*)
	    echo $1
	    ;;
	.)
	    echo $pwd
	    ;;
	./*)
	    echo ${pwd}${1#.}
	    ;;
	..)
	    cd ..
	    echo $PWD
	    cd $pwd
	    ;;
	../*)
	    cd ..
	    resolve_file ${1#../}
	    cd $pwd
	    ;;
	*)
	    echo $pwd/$1
	    ;;
    esac
}

# Determine which version of mktemp is present (if any) and set MKTEMP accortingly:
#
#     None - No mktemp
#     BSD  - BSD mktemp (Mandrake)
#     STD  - mktemp.org mktemp
#
find_mktemp() {
    local mktemp
    mktemp=`mywhich mktemp 2> /dev/null`

    if [ -n "$mktemp" ]; then
	if qt mktemp -V ; then
	    MKTEMP=STD
	else
	    MKTEMP=BSD
	fi
    else
	MKTEMP=None
    fi
}

#
# create a temporary file. If a directory name is passed, the file will be created in
# that directory. Otherwise, it will be created in a temporary directory.
#
mktempfile() {

    [ -z "$MKTEMP" ] && find_mktemp

    if [ $# -gt 0 ]; then
	case "$MKTEMP" in
	    BSD)
		mktemp $1/shorewall.XXXXXX
		;;
	    STD)
		mktemp -p $1 shorewall.XXXXXX
		;;
	    None)
		> $1/shorewall-$$ && echo $1/shorewall-$$
		;;
	    *)
		error_message "ERROR:Internal error in mktempfile"
		;;
	esac
    else
	case "$MKTEMP" in
	    BSD)
		mktemp ${TMPDIR:-/tmp}/shorewall.XXXXXX
		;;
	    STD)
		mktemp -t shorewall.XXXXXX
		;;
	    None)
		rm -f ${TMPDIR:-/tmp}/shorewall-$$
		> ${TMPDIR:-}/shorewall-$$ && echo ${TMPDIR:-/tmp}/shorewall-$$
		;;
	    *)
		error_message "ERROR:Internal error in mktempfile"
		;;
	esac
    fi
}