openwrt-owl/package/firewall/files/lib/core_init.sh

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# Copyright (C) 2009-2010 OpenWrt.org
# Copyright (C) 2008 John Crispin <blogic@openwrt.org>
FW_INITIALIZED=
FW_ZONES=
FW_ZONES4=
FW_ZONES6=
FW_CONNTRACK_ZONES=
FW_NOTRACK_DISABLED=
FW_DEFAULTS_APPLIED=
FW_ADD_CUSTOM_CHAINS=
FW_ACCEPT_REDIRECTS=
FW_ACCEPT_SRC_ROUTE=
FW_DEFAULT_INPUT_POLICY=REJECT
FW_DEFAULT_OUTPUT_POLICY=REJECT
FW_DEFAULT_FORWARD_POLICY=REJECT
FW_DISABLE_IPV4=0
FW_DISABLE_IPV6=0
fw_load_defaults() {
fw_config_get_section "$1" defaults { \
string input $FW_DEFAULT_INPUT_POLICY \
string output $FW_DEFAULT_OUTPUT_POLICY \
string forward $FW_DEFAULT_FORWARD_POLICY \
boolean drop_invalid 0 \
boolean syn_flood 0 \
boolean synflood_protect 0 \
string synflood_rate 25 \
string synflood_burst 50 \
boolean tcp_syncookies 1 \
boolean tcp_ecn 0 \
boolean tcp_westwood 0 \
boolean tcp_window_scaling 1 \
boolean accept_redirects 0 \
boolean accept_source_route 0 \
boolean custom_chains 1 \
boolean disable_ipv6 0 \
} || return
[ -n "$FW_DEFAULTS_APPLIED" ] && {
fw_log error "duplicate defaults section detected, skipping"
return 1
}
FW_DEFAULTS_APPLIED=1
FW_DEFAULT_INPUT_POLICY=$defaults_input
FW_DEFAULT_OUTPUT_POLICY=$defaults_output
FW_DEFAULT_FORWARD_POLICY=$defaults_forward
FW_ADD_CUSTOM_CHAINS=$defaults_custom_chains
FW_ACCEPT_REDIRECTS=$defaults_accept_redirects
FW_ACCEPT_SRC_ROUTE=$defaults_accept_source_route
FW_DISABLE_IPV6=$defaults_disable_ipv6
fw_callback pre defaults
# Seems like there are only one sysctl for both IP versions.
for s in syncookies ecn westwood window_scaling; do
eval "sysctl -e -w net.ipv4.tcp_${s}=\$defaults_tcp_${s}" >/dev/null
done
fw_sysctl_interface all
[ $defaults_drop_invalid == 1 ] && {
fw add i f INPUT DROP { -m state --state INVALID }
fw add i f OUTPUT DROP { -m state --state INVALID }
fw add i f FORWARD DROP { -m state --state INVALID }
FW_NOTRACK_DISABLED=1
}
fw add i f INPUT ACCEPT { -m state --state RELATED,ESTABLISHED }
fw add i f OUTPUT ACCEPT { -m state --state RELATED,ESTABLISHED }
fw add i f FORWARD ACCEPT { -m state --state RELATED,ESTABLISHED }
fw add i f INPUT ACCEPT { -i lo }
fw add i f OUTPUT ACCEPT { -o lo }
# Compatibility to old 'syn_flood' parameter
[ $defaults_syn_flood == 1 ] && \
defaults_synflood_protect=1
[ "${defaults_synflood_rate%/*}" == "$defaults_synflood_rate" ] && \
defaults_synflood_rate="$defaults_synflood_rate/second"
[ $defaults_synflood_protect == 1 ] && {
echo "Loading synflood protection"
fw_callback pre synflood
fw add i f syn_flood
fw add i f syn_flood RETURN { \
-p tcp --syn \
-m limit --limit "${defaults_synflood_rate}" --limit-burst "${defaults_synflood_burst}" \
}
fw add i f syn_flood DROP
fw add i f INPUT syn_flood { -p tcp --syn }
fw_callback post synflood
}
[ $defaults_custom_chains == 1 ] && {
echo "Adding custom chains"
fw add i f input_rule
fw add i f output_rule
fw add i f forwarding_rule
fw add i n prerouting_rule
fw add i n postrouting_rule
fw add i f INPUT input_rule
fw add i f OUTPUT output_rule
fw add i f FORWARD forwarding_rule
fw add i n PREROUTING prerouting_rule
fw add i n POSTROUTING postrouting_rule
}
fw add i f input
fw add i f output
fw add i f forward
fw add i f INPUT input
fw add i f OUTPUT output
fw add i f FORWARD forward
fw add i f reject
fw add i f reject REJECT { --reject-with tcp-reset -p tcp }
fw add i f reject REJECT { --reject-with port-unreach }
fw_set_filter_policy
fw_callback post defaults
}
fw_config_get_zone() {
[ "${zone_NAME}" != "$1" ] || return
fw_config_get_section "$1" zone { \
string name "$1" \
string network "" \
string input "$FW_DEFAULT_INPUT_POLICY" \
string output "$FW_DEFAULT_OUTPUT_POLICY" \
string forward "$FW_DEFAULT_FORWARD_POLICY" \
boolean masq 0 \
string masq_src "" \
string masq_dest "" \
boolean conntrack 0 \
boolean mtu_fix 0 \
boolean custom_chains "$FW_ADD_CUSTOM_CHAINS" \
boolean log 0 \
string log_limit 10 \
string family "" \
} || return
[ -n "$zone_name" ] || zone_name=$zone_NAME
[ -n "$zone_network" ] || zone_network=$zone_name
}
fw_load_zone() {
fw_config_get_zone "$1"
list_contains FW_ZONES $zone_name && {
fw_log error "zone ${zone_name}: duplicated zone, skipping"
return 0
}
append FW_ZONES $zone_name
fw_callback pre zone
[ $zone_conntrack = 1 -o $zone_masq = 1 ] && \
append FW_CONNTRACK_ZONES "$zone_name"
local mode
case "$zone_family" in
*4)
mode=4
append FW_ZONES4 $zone_name
uci_set_state firewall core ${zone_name}_ipv4 1
;;
*6)
mode=6
append FW_ZONES6 $zone_name
uci_set_state firewall core ${zone_name}_ipv6 1
;;
*)
mode=i
append FW_ZONES4 $zone_name
append FW_ZONES6 $zone_name
uci_set_state firewall core ${zone_name}_ipv4 1
uci_set_state firewall core ${zone_name}_ipv6 1
;;
esac
local chain=zone_${zone_name}
fw add $mode f ${chain}_ACCEPT
fw add $mode f ${chain}_DROP
fw add $mode f ${chain}_REJECT
fw add $mode f ${chain}_MSSFIX
# TODO: Rename to ${chain}_input
fw add $mode f ${chain}
fw add $mode f ${chain} ${chain}_${zone_input} $
fw add $mode f ${chain}_forward
fw add $mode f ${chain}_forward ${chain}_${zone_forward} $
# TODO: add ${chain}_output
fw add $mode f output ${chain}_${zone_output} $
# TODO: Rename to ${chain}_MASQUERADE
fw add $mode n ${chain}_nat
fw add $mode n ${chain}_prerouting
fw add $mode r ${chain}_notrack
[ $zone_mtu_fix == 1 ] && \
fw add $mode f FORWARD ${chain}_MSSFIX ^
[ $zone_custom_chains == 1 ] && {
[ $FW_ADD_CUSTOM_CHAINS == 1 ] || \
fw_die "zone ${zone_name}: custom_chains globally disabled"
fw add $mode f input_${zone_name}
fw add $mode f ${chain} input_${zone_name} ^
fw add $mode f forwarding_${zone_name}
fw add $mode f ${chain}_forward forwarding_${zone_name} ^
fw add $mode n prerouting_${zone_name}
fw add $mode n ${chain}_prerouting prerouting_${zone_name} ^
}
[ "$zone_log" == 1 ] && {
[ "${zone_log_limit%/*}" == "$zone_log_limit" ] && \
zone_log_limit="$zone_log_limit/minute"
local t
for t in REJECT DROP MSSFIX; do
fw add $mode f ${chain}_${t} LOG ^ \
{ -m limit --limit $zone_log_limit --log-prefix "$t($zone_name): " }
done
}
# NB: if MASQUERADING for IPv6 becomes available we'll need a family check here
if [ "$zone_masq" == 1 ]; then
local msrc mdst
for msrc in ${zone_masq_src:-0.0.0.0/0}; do
case "$msrc" in
*.*) fw_get_negation msrc '-s' "$msrc" ;;
*) fw_get_subnet4 msrc '-s' "$msrc" ;;
esac
for mdst in ${zone_masq_dest:-0.0.0.0/0}; do
case "$mdst" in
*.*) fw_get_negation mdst '-d' "$mdst" ;;
*) fw_get_subnet4 mdst '-d' "$mdst" ;;
esac
fw add $mode n ${chain}_nat MASQUERADE $ { $msrc $mdst }
done
done
fi
fw_callback post zone
}
fw_load_notrack_zone() {
fw_config_get_zone "$1"
list_contains FW_CONNTRACK_ZONES "${zone_name}" && return
fw_callback pre notrack
fw add i r zone_${zone_name}_notrack NOTRACK $
fw_callback post notrack
}
fw_load_include() {
local name="$1"
local path
config_get path ${name} path
[ -e $path ] && ( . $path )
}
fw_clear() {
local policy=$1
fw_set_filter_policy $policy
local tab
for tab in f n r; do
fw del i $tab
done
}
fw_set_filter_policy() {
local policy=$1
local chn tgt
for chn in INPUT OUTPUT FORWARD; do
eval "tgt=\${policy:-\${FW_DEFAULT_${chn}_POLICY}}"
[ $tgt == "REJECT" ] && tgt=reject
[ $tgt == "ACCEPT" -o $tgt == "DROP" ] || {
fw add i f $chn $tgt $
tgt=DROP
}
fw policy i f $chn $tgt
done
}
fw_callback() {
local pp=$1
local hk=$2
local libs lib
eval "libs=\$FW_CB_${pp}_${hk}"
[ -n "$libs" ] || return
for lib in $libs; do
${lib}_${pp}_${hk}_cb
done
}