#!/bin/sh /etc/rc.common
#
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START=89

USE_PROCD=1

OTBR_FORWARD_INGRESS_CHAIN="OTBR_FORWARD_INGRESS"
THREAD_IF_BACKUP_FILE="/tmp/otbr-firewall"

ipset_destroy_if_exist()
{
    if ipset list "$1"; then
        ipset destroy "$1"
    fi
}

stop_service()
{
    if [ -f "$THREAD_IF_BACKUP_FILE" ]; then
        THREAD_IF_NAME=$(cat $THREAD_IF_BACKUP_FILE)

        while ip6tables -C FORWARD -o $THREAD_IF_NAME -j $OTBR_FORWARD_INGRESS_CHAIN; do
            ip6tables -D FORWARD -o $THREAD_IF_NAME -j $OTBR_FORWARD_INGRESS_CHAIN
        done

        if ip6tables -L $OTBR_FORWARD_INGRESS_CHAIN; then
            ip6tables -w -F $OTBR_FORWARD_INGRESS_CHAIN
            ip6tables -w -X $OTBR_FORWARD_INGRESS_CHAIN
        fi

        ipset_destroy_if_exist otbr-ingress-deny-src
        ipset_destroy_if_exist otbr-ingress-deny-src-swap
        ipset_destroy_if_exist otbr-ingress-allow-dst
        ipset_destroy_if_exist otbr-ingress-allow-dst-swap

        rm $THREAD_IF_BACKUP_FILE
    fi
}

start_service()
{
    THREAD_IF_NAME=$(uci -q get otbr-agent.service.thread_if_name)
    echo "$THREAD_IF_NAME" > "$THREAD_IF_BACKUP_FILE"

    ipset create -exist otbr-ingress-deny-src hash:net family inet6
    ipset create -exist otbr-ingress-deny-src-swap hash:net family inet6
    ipset create -exist otbr-ingress-allow-dst hash:net family inet6
    ipset create -exist otbr-ingress-allow-dst-swap hash:net family inet6

    ip6tables -N $OTBR_FORWARD_INGRESS_CHAIN
    ip6tables -I FORWARD 1 -o $THREAD_IF_NAME -j $OTBR_FORWARD_INGRESS_CHAIN

    ip6tables -A $OTBR_FORWARD_INGRESS_CHAIN -m pkttype --pkt-type unicast -i $THREAD_IF_NAME -p ip -j DROP
    ip6tables -A $OTBR_FORWARD_INGRESS_CHAIN -m set --match-set otbr-ingress-deny-src src -p ip -j DROP
    ip6tables -A $OTBR_FORWARD_INGRESS_CHAIN -m set --match-set otbr-ingress-allow-dst dst -p ip -j ACCEPT
    ip6tables -A $OTBR_FORWARD_INGRESS_CHAIN -m pkttype --pkt-type unicast -p ip -j DROP
    ip6tables -A $OTBR_FORWARD_INGRESS_CHAIN -p ip -j ACCEPT
}
