script/_firewall

#!/bin/bash
#
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FIREWALL_SERVICE=/etc/init.d/otbr-firewall

sudo modprobe ip6table_filter || true

FIREWALL="${FIREWALL:-1}"

# When otbr-agent is built with the opt-in in-process nftables firewall
# backend (-DOTBR_NFTABLES=ON), it owns the OTBR ingress filter, so the
# legacy ipset/ip6tables service must not be installed alongside it. The
# build records which backend it chose in a marker file; an explicit
# OTBR_NFTABLES in the environment overrides it.
OTBR_NFTABLES_MARKER="/usr/share/otbr/nftables-backend"
if [ -z "${OTBR_NFTABLES:-}" ]; then
    # The marker carries the value the build decided, not just its presence:
    # installing does not uninstall, so a file that could only say "on" would
    # outlive a rebuild with the option turned back off. Anything missing or
    # unrecognised means the legacy path, which over-filters rather than
    # leaving the router with no ingress filter at all.
    OTBR_NFTABLES=0
    if [ -r "${OTBR_NFTABLES_MARKER}" ] && grep -qx '1' "${OTBR_NFTABLES_MARKER}"; then
        OTBR_NFTABLES=1
    fi
fi

firewall_uninstall()
{
    with FIREWALL || return 0

    firewall_stop
    if have systemctl; then
        sudo systemctl disable otbr-firewall || true
    fi
    # systemctl disable doesn't remove sym-links
    if have update-rc.d; then
        sudo update-rc.d otbr-firewall remove || true
    fi
    test ! -f $FIREWALL_SERVICE || sudo rm $FIREWALL_SERVICE
}

firewall_install()
{
    with FIREWALL || return 0

    if [ "${OTBR_NFTABLES}" = "1" ]; then
        echo "OTBR_NFTABLES=1: OTBR ingress filter is managed in-process (nftables); skipping legacy firewall service."
        return 0
    fi

    sudo cp script/otbr-firewall $FIREWALL_SERVICE
    sudo chmod a+x $FIREWALL_SERVICE
    if have systemctl; then
        sudo systemctl enable otbr-firewall || die 'Failed to enable firewall service!'
        sudo systemctl start otbr-firewall || die 'Failed to start firewall service!'
    fi
}

firewall_start()
{
    # Same gate as the install: with the in-process backend there is no
    # otbr-firewall service to start, and starting the legacy one would put
    # its chain alongside the agent's.
    if [ "${OTBR_NFTABLES}" = "1" ]; then
        return 0
    fi

    with FIREWALL || return 0

    if with DOCKER; then
        service otbr-firewall start || die 'Failed to start firewall service'
    elif have systemctl; then
        sudo systemctl start otbr-firewall || die 'Failed to start firewall service'
    fi
}

firewall_stop()
{
    with FIREWALL || return 0

    if with DOCKER; then
        service otbr-firewall stop || true
    elif have systemctl; then
        sudo systemctl stop otbr-firewall || true
    fi
}