#!/bin/sh

[ -n "$INCLUDE_ONLY" ] || {
        . /lib/functions.sh
        . /lib/functions/network.sh
        . ../netifd-proto.sh
        init_proto "$@"
}

gre_generic_setup() {
        local cfg="$1"
        local mode="$2"
        local local="$3"
        local remote="$4"
        local link="$5"
        local mtu ttl tos zone ikey okey icsum ocsum iseqno oseqno
        json_get_vars mtu ttl tos zone ikey okey icsum ocsum iseqno oseqno

        [ -z "$zone" ] && zone="wan"

        proto_init_update "$link" 1

        proto_add_tunnel
        json_add_string mode "$mode"
        json_add_int mtu "${mtu:-1280}"
        [ -n "$df" ] && json_add_boolean df "$df"
        json_add_int ttl "${ttl:-64}"
        [ -n "$tos" ] && json_add_string tos "$tos"
        json_add_string local "$local"
        json_add_string remote "$remote"
        [ -n "$tunlink" ] && json_add_string link "$tunlink"
        json_add_string info "${ikey:-0},${okey:-0},${icsum:-0},${ocsum:-0},${iseqno:-0},${oseqno:-0}"
        proto_close_tunnel

        proto_add_data
        [ -n "$zone" ] && json_add_string zone "$zone"
        proto_close_data

        proto_send_update "$cfg"
}

gre_setup() {
        local cfg="$1"
        local mode="$2"

        local ipaddr peeraddr
        json_get_vars df ipaddr peeraddr tunlink

        [ -z "$peeraddr" ] && {
                proto_notify_error "$cfg" "MISSING_ADDRESS"
                proto_block_restart "$cfg"
                exit
        }

        ( proto_add_host_dependency "$cfg" "$peeraddr" "$tunlink" )

        [ -z "$ipaddr" ] && {
                local wanif="$tunlink"
                if [ -z $wanif ] && ! network_find_wan wanif; then
                        proto_notify_error "$cfg" "NO_WAN_LINK"
                        exit
                fi

                if ! network_get_ipaddr ipaddr "$wanif"; then
                        proto_notify_error "$cfg" "NO_WAN_LINK"
                        exit
                fi
        }

        [ -z "$df" ] && df="1"

        gre_generic_setup $cfg $mode $ipaddr $peeraddr "gre-$cfg"
}

proto_gre_setup() {
        local cfg="$1"

        gre_setup $cfg "greip"
}

proto_gretap_setup() {
        local cfg="$1"

        local network
        json_get_vars network

        gre_setup $cfg "gretapip"

        json_init
        json_add_string name "gre-$cfg"
        json_add_boolean link-ext 0
        json_close_object

        for i in $network; do
                ubus call network.interface."$i" add_device "$(json_dump)"
        done
}

grev6_setup() {
        local cfg="$1"
        local mode="$2"

        local ip6addr peer6addr weakif
        json_get_vars ip6addr peer6addr tunlink weakif

        [ -z "$peer6addr" ] && {
                proto_notify_error "$cfg" "MISSING_ADDRESS"
                proto_block_restart "$cfg"
                exit
        }

        ( proto_add_host_dependency "$cfg" "$peer6addr" "$tunlink" )

        [ -z "$ip6addr" ] && {
                local wanif="$tunlink"
                if [ -z $wanif ] && ! network_find_wan6 wanif; then
                        proto_notify_error "$cfg" "NO_WAN_LINK"
                        exit
                fi

                if ! network_get_ipaddr6 ip6addr "$wanif"; then
                        [ -z "$weakif" ] && weakif="lan"
                        if ! network_get_ipaddr6 ip6addr "$weakif"; then
                                proto_notify_error "$cfg" "NO_WAN_LINK"
                                exit
                        fi
                fi
        }

        gre_generic_setup $cfg $mode $ip6addr $peer6addr "grev6-$cfg"
}

proto_grev6_setup() {
        local cfg="$1"

        grev6_setup $cfg "greip6"
}

proto_grev6tap_setup() {
        local cfg="$1"

        local network
        json_get_vars network

        grev6_setup $cfg "gretapip6"

        json_init
        json_add_string name "grev6-$cfg"
        json_add_boolean link-ext 0
        json_close_object

        for i in $network; do
                ubus call network.interface."$i" add_device "$(json_dump)"
        done
}

gretap_generic_teardown() {
        local network
        json_get_vars network

        json_init
        json_add_string name "$1"
        json_add_boolean link-ext 0
        json_close_object

        for i in $network; do
                ubus call network.interface."$i" remove_device "$(json_dump)"
        done
}

proto_gre_teardown() {
        local cfg="$1"
}

proto_gretap_teardown() {
        local cfg="$1"

        gretap_generic_teardown "gre-$cfg"
}

proto_grev6_teardown() {
        local cfg="$1"
}

proto_grev6tap_teardown() {
        local cfg="$1"

        gretap_generic_teardown "grev6-$cfg"
}

gre_generic_init_config() {
        no_device=1
        available=1

        proto_config_add_int "mtu"
        proto_config_add_int "ttl"
        proto_config_add_string "tos"
        proto_config_add_string "tunlink"
        proto_config_add_string "zone"
        proto_config_add_int "ikey"
        proto_config_add_int "okey"
        proto_config_add_boolean "icsum"
        proto_config_add_boolean "ocsum"
        proto_config_add_boolean "iseqno"
        proto_config_add_boolean "oseqno"
}

proto_gre_init_config() {
        gre_generic_init_config
        proto_config_add_string "ipaddr"
        proto_config_add_string "peeraddr"
        proto_config_add_boolean "df"
}

proto_gretap_init_config() {
        proto_gre_init_config
        proto_config_add_string "network"
}

proto_grev6_init_config() {
        gre_generic_init_config
        proto_config_add_string "ip6addr"
        proto_config_add_string "peer6addr"
        proto_config_add_string "weakif"
}

proto_grev6tap_init_config() {
        proto_grev6_init_config
        proto_config_add_string "network"
}

[ -n "$INCLUDE_ONLY" ] || {
        [ -f /lib/modules/$(uname -r)/gre.ko ] && add_protocol gre
        [ -f /lib/modules/$(uname -r)/gre.ko ] && add_protocol gretap
        [ -f /lib/modules/$(uname -r)/ip6_gre.ko ] && add_protocol grev6
        [ -f /lib/modules/$(uname -r)/ip6_gre.ko ] && add_protocol grev6tap
}