package/6to4/files/6to4.sh

   1 # 6to4.sh - IPv6-in-IPv4 tunnel backend
   2 # Copyright (c) 2010 OpenWrt.org
   3
   4 find_6to4_wanif() {
   5         local if=$(ip -4 r l e 0.0.0.0/0); if="${if#default* dev }"; if="${if%% *}"
   6         [ -n "$if" ] && grep -qs "^ *$if:" /proc/net/dev && echo "$if"
   7 }
   8
   9 find_6to4_wanip() {
  10         local ip=$(ip -4 a s dev "$1"); ip="${ip#*inet }"
  11         echo "${ip%%[^0-9.]*}"
  12 }
  13
  14 find_6to4_prefix() {
  15         local ip4="$1"
  16         local oIFS="$IFS"; IFS="."; set -- $ip4; IFS="$oIFS"
  17
  18         printf "2002:%02x%02x:%02x%02x\n" $1 $2 $3 $4
  19 }
  20
  21 # Hook into scan_interfaces() to synthesize a .device option
  22 # This is needed for /sbin/ifup to properly dispatch control
  23 # to setup_interface_6to4() even if no .ifname is set in
  24 # the configuration.
  25 scan_6to4() {
  26         config_set "$1" device "6to4-$1"
  27 }
  28
  29 coldplug_interface_6to4() {
  30         setup_interface_6to4 "6to4-$1" "$1"
  31 }
  32
  33 setup_interface_6to4() {
  34         local iface="$1"
  35         local cfg="$2"
  36         local link="6to4-$cfg"
  37
  38         local local4=$(uci_get network "$cfg" ipaddr)
  39
  40         local mtu
  41         config_get mtu "$cfg" mtu
  42
  43         local ttl
  44         config_get ttl "$cfg" ttl
  45
  46         local defaultroute
  47         config_get_bool defaultroute "$cfg" defaultroute 1
  48
  49         local wanif=$(find_6to4_wanif)
  50         [ -z "$wanif" ] && {
  51                 logger -t "$link" "Cannot find wan interface - aborting"
  52                 return
  53         }
  54
  55         local wancfg=$(find_config "$wanif")
  56         [ -z "$wancfg" ] && {
  57                 logger -t "$link" "Cannot find wan network - aborting"
  58                 return
  59         }
  60
  61         # If local4 is unset, guess local IPv4 address from the
  62         # interface used by the default route.
  63         [ -z "$local4" ] && {
  64                 [ -n "$wanif" ] && {
  65                         local4=$(find_6to4_wanip "$wanif")
  66                         uci_set_state network "$cfg" wan_device "$wanif"
  67                 }
  68         }
  69
  70         [ -n "$local4" ] && {
  71                 logger -t "$link" "Starting ..."
  72
  73                 # creating the tunnel below will trigger a net subsystem event
  74                 # prevent it from touching or iface by disabling .auto here
  75                 uci_set_state network "$cfg" ifname $link
  76                 uci_set_state network "$cfg" auto 0
  77
  78                 # find our local prefix
  79                 local prefix6=$(find_6to4_prefix "$local4")
  80                 local local6="$prefix6::1/16"
  81
  82                 logger -t "$link" " * IPv4 address is $local4"
  83                 logger -t "$link" " * IPv6 address is $local6"
  84                 ip tunnel add $link mode sit remote any local $local4 ttl ${ttl:-64}
  85                 ip link set $link up
  86                 ip link set mtu ${mtu:-1280} dev $link
  87                 ip addr add $local6 dev $link
  88
  89                 uci_set_state network "$cfg" ipaddr $local4
  90                 uci_set_state network "$cfg" ip6addr $local6
  91
  92                 [ "$defaultroute" = 1 ] && {
  93                         logger -t "$link" " * Adding default route"
  94                         ip -6 route add 2000::/3 via ::192.88.99.1 dev $link metric 1
  95                         uci_set_state network "$cfg" defaultroute 1
  96                 }
  97
  98                 # find delegation target
  99                 local adv_interface
 100                 config_get adv_interface "$cfg" adv_interface
 101
 102                 local adv_ifname
 103                 config_get adv_ifname "${adv_interface:-lan}" ifname
 104
 105                 local adv_subnet=$(uci_get network "$cfg" adv_subnet)
 106
 107                 grep -qs "^ *$adv_ifname:" /proc/net/dev && {
 108                         local subnet6="$prefix6:${adv_subnet:-1}::1/64"
 109
 110                         logger -t "$link" " * Advertising IPv6 subnet $subnet6 on ${adv_interface:-lan} ($adv_ifname)"
 111                         ip -6 addr add $subnet6 dev $adv_ifname
 112                         uci_set_state network "$cfg" adv_subnet "$subnet6"
 113                         uci_set_state network "$cfg" adv_ifname "$adv_ifname"
 114
 115                         [ -f /etc/config/radvd ] && /etc/init.d/radvd enabled && {
 116                                 local sid="6to4_$cfg"
 117
 118                                 uci -q batch <<-EOF
 119                                         revert radvd.iface_$sid
 120                                         revert radvd.prefix_$sid
 121                                         set radvd.iface_$sid=interface
 122                                         set radvd.iface_$sid.ignore=0
 123                                         set radvd.iface_$sid.interface=${adv_interface:-lan}
 124                                         set radvd.iface_$sid.IgnoreIfMissing=1
 125                                         set radvd.iface_$sid.AdvSendAdvert=1
 126                                         set radvd.iface_$sid.MaxRtrAdvInterval=30
 127                                         set radvd.prefix_$sid=prefix
 128                                         set radvd.prefix_$sid.ignore=0
 129                                         set radvd.prefix_$sid.interface=${adv_interface:-lan}
 130                                         set radvd.prefix_$sid.prefix=0:0:0:${adv_subnet:-1}::/64
 131                                         set radvd.prefix_$sid.AdvOnLink=1
 132                                         set radvd.prefix_$sid.AdvAutonomous=1
 133                                         set radvd.prefix_$sid.AdvValidLifetime=300
 134                                         set radvd.prefix_$sid.AdvPreferredLifetime=120
 135                                         set radvd.prefix_$sid.Base6to4Interface=$wancfg
 136                                 EOF
 137
 138                                 /etc/init.d/radvd restart
 139                         }
 140                 }
 141
 142                 logger -t "$link" "... started"
 143
 144                 env -i ACTION="ifup" INTERFACE="$cfg" DEVICE="$link" PROTO=6to4 /sbin/hotplug-call "iface" &
 145         } || {
 146                 echo "Cannot determine local IPv4 address for 6to4 tunnel $cfg - skipping"
 147         }
 148 }
 149
 150 stop_interface_6to4() {
 151         local cfg="$1"
 152         local link="6to4-$cfg"
 153
 154         local local6=$(uci_get_state network "$cfg" ip6addr)
 155         local defaultroute=$(uci_get_state network "$cfg" defaultroute)
 156
 157         local adv_subnet=$(uci_get_state network "$cfg" adv_subnet)
 158         local adv_ifname=$(uci_get_state network "$cfg" adv_ifname)
 159
 160         grep -qs "^ *$link:" /proc/net/dev && {
 161                 logger -t "$link" "Shutting down ..."
 162                 env -i ACTION="ifdown" INTERFACE="$cfg" DEVICE="$link" PROTO=6to4 /sbin/hotplug-call "iface" &
 163
 164                 [ -n "$adv_subnet" ] && [ -n "$adv_ifname" ] && {
 165                         local sid="6to4_$cfg"
 166
 167                         uci -q batch <<-EOF
 168                                 revert radvd.iface_$sid
 169                                 revert radvd.prefix_$sid
 170                         EOF
 171
 172                         /etc/init.d/radvd enabled && /etc/init.d/radvd restart
 173
 174                         ip -6 addr del $adv_subnet dev $adv_ifname
 175                 }
 176
 177                 [ "$defaultroute" = "1" ] && {
 178                         ip -6 route del 2000::/3 via ::192.88.99.1 dev $link metric 1
 179                 }
 180
 181                 ip addr del $local6 dev $link
 182                 ip link set $link down
 183                 ip tunnel del $link
 184
 185                 logger -t "$link" "... stopped"
 186         }
 187 }