package/firewall/files/reflection.hotplug

   1 #!/bin/sh
   2
   3 . /etc/functions.sh
   4 . /usr/share/libubox/jshn.sh
   5
   6 find_iface_address()
   7 {
   8         local iface="$1"
   9         local ipaddr="$2"
  10         local prefix="$3"
  11
  12         local tmp="$(ubus call network.interface."$iface" status 2>/dev/null)"
  13
  14         json_load "${tmp:-{}}"
  15         json_get_type tmp address
  16
  17         if [ "$tmp" = array ]; then
  18
  19                 json_select address
  20                 json_get_type tmp 1
  21
  22                 if [ "$tmp" = object ]; then
  23
  24                         json_select 1
  25                         [ -n "$ipaddr" ] && json_get_var "$ipaddr" address
  26                         [ -n "$prefix" ] && json_get_var "$prefix" mask
  27
  28                 fi
  29         fi
  30 }
  31
  32 if [ "$ACTION" = "add" ] && [ "$INTERFACE" = "wan" ]; then
  33         local wanip
  34         find_iface_address wan wanip
  35         [ -n "$wanip" ] || return
  36
  37         iptables -t nat -F nat_reflection_in 2>/dev/null || {
  38                 iptables -t nat -N nat_reflection_in
  39                 iptables -t nat -A prerouting_rule -j nat_reflection_in
  40         }
  41
  42         iptables -t nat -F nat_reflection_out 2>/dev/null || {
  43                 iptables -t nat -N nat_reflection_out
  44                 iptables -t nat -A postrouting_rule -j nat_reflection_out
  45         }
  46
  47         iptables -t filter -F nat_reflection_fwd 2>/dev/null || {
  48                 iptables -t filter -N nat_reflection_fwd
  49                 iptables -t filter -A forwarding_rule -j nat_reflection_fwd
  50         }
  51
  52         find_networks() {
  53                 find_networks_cb() {
  54                         local cfg="$1"
  55                         local zone="$2"
  56
  57                         local name
  58                         config_get name "$cfg" name
  59
  60                         [ "$name" = "$zone" ] && {
  61                                 local network
  62                                 config_get network "$cfg" network
  63
  64                                 echo ${network:-$zone}
  65                                 return 1
  66                         }
  67                 }
  68
  69                 config_foreach find_networks_cb zone "$1"
  70         }
  71
  72         setup_fwd() {
  73                 local cfg="$1"
  74
  75                 local reflection
  76                 config_get_bool reflection "$cfg" reflection 1
  77                 [ "$reflection" == 1 ] || return
  78
  79                 local src
  80                 config_get src "$cfg" src
  81
  82                 local target
  83                 config_get target "$cfg" target DNAT
  84
  85                 [ "$src" = wan ] && [ "$target" = DNAT ] && {
  86                         local dest
  87                         config_get dest "$cfg" dest "lan"
  88                         [ "$dest" != "*" ] || return
  89
  90                         local net
  91                         for net in $(find_networks "$dest"); do
  92                                 local lanip lanmk
  93                                 find_iface_address "$net" lanip lanmk
  94                                 [ -n "$lanip" ] || return
  95
  96                                 local proto
  97                                 config_get proto "$cfg" proto
  98
  99                                 local epmin epmax extport
 100                                 config_get extport "$cfg" src_dport
 101                                 [ -n "$extport" ] || return
 102
 103                                 epmin="${extport%[-:]*}"; epmax="${extport#*[-:]}"
 104                                 [ "${epmin#!}" != "$epmax" ] || epmax=""
 105
 106                                 local ipmin ipmax intport
 107                                 config_get intport "$cfg" dest_port "$extport"
 108
 109                                 ipmin="${intport%[-:]*}"; ipmax="${intport#*[-:]}"
 110                                 [ "${ipmin#!}" != "$ipmax" ] || ipmax=""
 111
 112                                 local exthost
 113                                 config_get exthost "$cfg" src_dip "$wanip"
 114
 115                                 local inthost
 116                                 config_get inthost "$cfg" dest_ip
 117                                 [ -n "$inthost" ] || return
 118
 119                                 [ "$proto" = tcpudp ] && proto="tcp udp"
 120
 121                                 [ "${inthost#!}" = "$inthost" ] || return 0
 122                                 [ "${exthost#!}" = "$exthost" ] || return 0
 123
 124                                 [ "${epmin#!}" != "$epmin" ] && \
 125                                         extport="! --dport ${epmin#!}${epmax:+:$epmax}" || \
 126                                         extport="--dport $epmin${epmax:+:$epmax}"
 127
 128                                 [ "${ipmin#!}" != "$ipmin" ] && \
 129                                         intport="! --dport ${ipmin#!}${ipmax:+:$ipmax}" || \
 130                                         intport="--dport $ipmin${ipmax:+:$ipmax}"
 131
 132                                 local p
 133                                 for p in ${proto:-tcp udp}; do
 134                                         case "$p" in
 135                                                 tcp|udp|6|17)
 136                                                         iptables -t nat -A nat_reflection_in \
 137                                                                 -s $lanip/$lanmk -d $exthost \
 138                                                                 -p $p $extport \
 139                                                                 -j DNAT --to $inthost:${ipmin#!}${ipmax:+-$ipmax}
 140
 141                                                         iptables -t nat -A nat_reflection_out \
 142                                                                 -s $lanip/$lanmk -d $inthost \
 143                                                                 -p $p $intport \
 144                                                                 -j SNAT --to-source $lanip
 145
 146                                                         iptables -t filter -A nat_reflection_fwd \
 147                                                                 -s $lanip/$lanmk -d $inthost \
 148                                                                 -p $p $intport \
 149                                                                 -j ACCEPT
 150                                                 ;;
 151                                         esac
 152                                 done
 153                         done
 154                 }
 155         }
 156
 157         config_load firewall
 158         config_foreach setup_fwd redirect
 159 fi