contrib/package/freifunk-gwcheck/files/usr/sbin/ff_olsr_test_gw.sh

   1 #!/bin/sh
   2
   3 #check if dyngw_plain is installed and enabled, else exit
   4 dyngwplainlib=`uci show olsrd |grep dyn_gw_plain |awk {' FS="."; print $1"."$2 '}`
   5 if [ -n "$dyngwplainlib" ]; then
   6         if [ "$(uci -q get $dyngwplainlib.ignore)" == 1 ]; then
   7                 exit 1
   8         fi
   9 else
  10         echo "dyngw_plain not found in olsrd config, exit"
  11         exit 1
  12 fi
  13
  14
  15 # check if we have a defaultroute with metric=0 in one of these tables: main table and gw-check table.
  16 # If not exit here.
  17 defroutemain="$(ip r s |grep default |grep -v metric)"
  18 defroutegwcheck="$(ip r s t gw-check |grep default |grep -v metric)"
  19 if [ -z "$defroutegwcheck" -a -z "$defroutemain" ]; then
  20         exit 1
  21 fi
  22
  23 # get and shuffle list of testservers
  24 testserver="$(uci -q get freifunk-gwcheck.hosts.host)"
  25 [ -z "$testserver" ] && echo "No testservers found, exit" && exit
  26
  27 testserver="$(for t in $testserver; do echo $t; done | awk 'BEGIN {
  28         srand();
  29 }
  30 {
  31         l[NR] = $0;
  32 }
  33
  34 END {
  35         for (i = 1; i <= NR; i++) {
  36                 n = int(rand() * (NR - i + 1)) + i;
  37                 print l[n];
  38                 l[n] = l[i];
  39         }
  40 }')"
  41
  42 check_internet() {
  43         for t in $testserver; do
  44                 local test
  45                 test=$(wget -q http://$t/conntest.html -O -| grep "Internet_works")
  46                 if [ "$test" == "Internet_works" ]; then
  47                         echo 0
  48                         break
  49                 else
  50                         logger -t gw-check "Could not get test file from http://$t/conntest.html"
  51                 fi
  52         done
  53 }
  54
  55 iw=$(check_internet)
  56
  57 if [ "$iw" == 0 ]; then
  58         # check if we have a seperate routing table for our tests.
  59         # If yes, move defaultroute to normal table and delete table gw-check
  60         if [ -n "$defroutegwcheck" ]; then
  61                 ip r a $defroutegwcheck
  62                 ip r d $defroutegwcheck t gw-check
  63                 ip ru del fwmark 0x2 lookup gw-check
  64                 for host in $testserver; do
  65                         iptables -t mangle -D OUTPUT -d $host -p tcp --dport 80 -j MARK --set-mark 0x2
  66                 done
  67                 logger -t gw-check "Internet is available again, restoring default route ( $defroutegwcheck)"
  68         fi
  69
  70 else
  71         # Check failed. If we have a defaultroute with metric=0 and it is already in table gw-check then do nothing.
  72         # If there is a defaultroute with metric=0 then remove it from the main routing table and add to table gw-check.
  73         if [ -z "$(ip ru s | grep gw-check)" -a -n "$defroutemain" ]; then
  74                 ip rule add fwmark 0x2 lookup gw-check
  75                 for host in $testserver; do
  76                         iptables -t mangle -I OUTPUT -d $host -p tcp --dport 80 -j MARK --set-mark 0x2
  77                 done
  78                 ip r a $defroutemain table gw-check
  79                 ip r d $defroutemain
  80                 logger -t gw-check "Internet is not available, deactivating the default route ( $defroutemain)"
  81         fi
  82 fi