1#!/bin/sh
2# 6to4.sh - IPv6-in-IPv4 tunnel backend
3# Copyright (c) 2010-2012 OpenWrt.org
4
5[ -n "$INCLUDE_ONLY" ] || {
6	. /lib/functions.sh
7	. /lib/functions/network.sh
8	. ../netifd-proto.sh
9	init_proto "$@"
10}
11
12find_6to4_prefix() {
13	local ip4="$1"
14	local oIFS="$IFS"; IFS="."; set -- $ip4; IFS="$oIFS"
15
16	printf "2002:%02x%02x:%02x%02x\n" $1 $2 $3 $4
17}
18
19test_6to4_rfc1918()
20{
21	local oIFS="$IFS"; IFS="."; set -- $1; IFS="$oIFS"
22	[ $1 -eq  10 ] && return 0
23	[ $1 -eq 192 ] && [ $2 -eq 168 ] && return 0
24	[ $1 -eq 172 ] && [ $2 -ge  16 ] && [ $2 -le  31 ] && return 0
25
26	# RFC 6598
27	[ $1 -eq 100 ] && [ $2 -ge  64 ] && [ $2 -le 127 ] && return 0
28
29	return 1
30}
31
32proto_6to4_setup() {
33	local cfg="$1"
34	local iface="$2"
35	local link="6to4-$cfg"
36
37	local mtu ttl tos ipaddr
38	json_get_vars mtu ttl tos ipaddr
39
40	( proto_add_host_dependency "$cfg" 0.0.0.0 )
41
42	local wanif
43	if ! network_find_wan wanif; then
44		proto_notify_error "$cfg" "NO_WAN_LINK"
45		return
46	fi
47
48	[ -z "$ipaddr" ] && {
49		if ! network_get_ipaddr ipaddr "$wanif"; then
50			proto_notify_error "$cfg" "NO_WAN_ADDRESS"
51			return
52		fi
53	}
54
55	test_6to4_rfc1918 "$ipaddr" && {
56		proto_notify_error "$cfg" "INVALID_LOCAL_ADDRESS"
57		return
58	}
59
60	# find our local prefix
61	local prefix6=$(find_6to4_prefix "$ipaddr")
62	local local6="$prefix6::1"
63
64	proto_init_update "$link" 1
65	proto_add_ipv6_address "$local6" 16
66	proto_add_ipv6_prefix "$prefix6::/48"
67
68	proto_add_ipv6_route "::" 0 "::192.88.99.1" "" "" "$local6/16"
69	proto_add_ipv6_route "::" 0 "::192.88.99.1" "" "" "$prefix6::/48"
70
71	proto_add_tunnel
72	json_add_string mode sit
73	json_add_int mtu "${mtu:-1280}"
74	json_add_int ttl "${ttl:-64}"
75	[ -n "$tos" ] && json_add_string tos "$tos"
76	json_add_string local "$ipaddr"
77	proto_close_tunnel
78
79	proto_send_update "$cfg"
80}
81
82proto_6to4_teardown() {
83	local cfg="$1"
84}
85
86proto_6to4_init_config() {
87	no_device=1
88	available=1
89
90	proto_config_add_string "ipaddr"
91	proto_config_add_int "mtu"
92	proto_config_add_int "ttl"
93	proto_config_add_string "tos"
94}
95
96[ -n "$INCLUDE_ONLY" ] || {
97	add_protocol 6to4
98}
99