package/firewall/files/lib/core_redirect.sh

   1 # Copyright (C) 2009-2010 OpenWrt.org
   2
   3 fw_config_get_redirect() {
   4         [ "${redirect_NAME}" != "$1" ] || return
   5         fw_config_get_section "$1" redirect { \
   6                 string _name "$1" \
   7                 string name "" \
   8                 string src "" \
   9                 ipaddr src_ip "" \
  10                 ipaddr src_dip "" \
  11                 string src_mac "" \
  12                 string src_port "" \
  13                 string src_dport "" \
  14                 string dest "" \
  15                 ipaddr dest_ip "" \
  16                 string dest_port "" \
  17                 string proto "tcpudp" \
  18                 string family "" \
  19                 string target "DNAT" \
  20                 string extra "" \
  21         } || return
  22         [ -n "$redirect_name" ] || redirect_name=$redirect__name
  23 }
  24
  25 fw_load_redirect() {
  26         fw_config_get_redirect "$1"
  27
  28         fw_callback pre redirect
  29
  30         local fwdchain natchain natopt nataddr natports srcdaddr srcdports
  31         if [ "$redirect_target" == "DNAT" ]; then
  32                 [ -n "${redirect_src#*}" -a -n "$redirect_dest_ip$redirect_dest_port" ] || {
  33                         fw_log error "DNAT redirect ${redirect_name}: needs src and dest_ip or dest_port, skipping"
  34                         return 0
  35                 }
  36
  37                 fwdopt=""
  38                 fwdchain=""
  39
  40                 # Check whether only ports are given or whether the given dest ip is local,
  41                 # in this case match only DNATed traffic and allow it on input, not forward
  42                 if [ -z "$redirect_dest_ip" ] || /sbin/ifconfig | grep -qE "addr:${redirect_dest_ip//./\\.}\b"; then
  43                         fwdopt="-m conntrack --ctstate DNAT"
  44                         fwdchain="zone_${redirect_src}"
  45                 else
  46                         fwdchain="zone_${redirect_src}_forward"
  47                 fi
  48
  49                 natopt="--to-destination"
  50                 natchain="zone_${redirect_src}_prerouting"
  51                 nataddr="$redirect_dest_ip"
  52                 fw_get_port_range natports "${redirect_dest_port#!}" "-"
  53
  54                 fw_get_negation srcdaddr '-d' "${redirect_src_dip:+$redirect_src_dip/$redirect_src_dip_prefixlen}"
  55                 fw_get_port_range srcdports "$redirect_src_dport" ":"
  56                 fw_get_negation srcdports '--dport' "$srcdports"
  57
  58                 list_contains FW_CONNTRACK_ZONES $redirect_src || \
  59                         append FW_CONNTRACK_ZONES $redirect_src
  60
  61         elif [ "$redirect_target" == "SNAT" ]; then
  62                 [ -n "${redirect_dest#*}" -a -n "$redirect_src_dip" ] || {
  63                         fw_log error "SNAT redirect ${redirect_name}: needs dest and src_dip, skipping"
  64                         return 0
  65                 }
  66
  67                 fwdchain="${redirect_src:+zone_${redirect_src}_forward}"
  68
  69                 natopt="--to-source"
  70                 natchain="zone_${redirect_dest}_nat"
  71                 nataddr="$redirect_src_dip"
  72                 fw_get_port_range natports "${redirect_src_dport#!}" "-"
  73
  74                 fw_get_negation srcdaddr '-d' "${redirect_dest_ip:+$redirect_dest_ip/$redirect_dest_ip_prefixlen}"
  75                 fw_get_port_range srcdports "$redirect_dest_port" ":"
  76                 fw_get_negation srcdports '--dport' "$srcdports"
  77
  78                 list_contains FW_CONNTRACK_ZONES $redirect_dest || \
  79                         append FW_CONNTRACK_ZONES $redirect_dest
  80
  81         else
  82                 fw_log error "redirect ${redirect_name}: target must be either DNAT or SNAT, skipping"
  83                 return 0
  84         fi
  85
  86         local mode
  87         fw_get_family_mode mode ${redirect_family:-x} ${redirect_src:-$redirect_dest} I
  88
  89         local srcaddr
  90         fw_get_negation srcaddr '-s' "${redirect_src_ip:+$redirect_src_ip/$redirect_src_ip_prefixlen}"
  91
  92         local srcports
  93         fw_get_port_range srcports "$redirect_src_port" ":"
  94         fw_get_negation srcports '--sport' "$srcports"
  95
  96         local destaddr
  97         fw_get_negation destaddr '-d' "${redirect_dest_ip:+$redirect_dest_ip/$redirect_dest_ip_prefixlen}"
  98
  99         local destports
 100         fw_get_port_range destports "${redirect_dest_port:-$redirect_src_dport}" ":"
 101         fw_get_negation destports '--dport' "$destports"
 102
 103         [ "$redirect_proto" == "tcpudp" ] && redirect_proto="tcp udp"
 104         local pr; for pr in $redirect_proto; do
 105                 fw_get_negation pr '-p' "$pr"
 106                 local sm; for sm in ${redirect_src_mac:-""}; do
 107                         fw_get_negation sm '--mac-source' "$sm"
 108                         fw add $mode n $natchain $redirect_target + \
 109                                 { $redirect_src_ip $redirect_dest_ip } { \
 110                                 $srcaddr $srcdaddr $pr \
 111                                 $srcports $srcdports \
 112                                 ${sm:+-m mac $sm} \
 113                                 $natopt $nataddr${natports:+:$natports} \
 114                                 $redirect_options \
 115                         }
 116
 117                         fw add $mode f ${fwdchain:-forward} ACCEPT + \
 118                                 { $redirect_src_ip $redirect_dest_ip } { \
 119                                 $srcaddr $destaddr \
 120                                 $pr \
 121                                 $srcports $destports \
 122                                 ${sm:+-m mac $sm} \
 123                                 $fwdopt \
 124                                 $redirect_extra \
 125                         }
 126                 done
 127         done
 128
 129         fw_callback post redirect
 130 }