diff options
Diffstat (limited to 'src/vpn_wrapper.sh')
| -rwxr-xr-x | src/vpn_wrapper.sh | 35 |
1 files changed, 16 insertions, 19 deletions
diff --git a/src/vpn_wrapper.sh b/src/vpn_wrapper.sh index 8dbb702..2dbb821 100755 --- a/src/vpn_wrapper.sh +++ b/src/vpn_wrapper.sh @@ -5,28 +5,25 @@ OVPN_COMMAND="/usr/sbin/openvpn" OPENVPN_CONFIG="$1" -PHYSICAL_IP="$2" -ROUTE_THROUGH_VETH="$3" -# rest of args is the command to run in network namespace -shift -shift -shift - # for routing some traffic from within the namespace to physical # network (e.g. database connection) we need to create a veth pair; +# ip datagrams routed through veth pair are going to have veth's private address +# as their source address - we need to change it to the address of our physical +# network device using iptables' SNAT. This address is provided by the caller. +PHYSICAL_IP="$2" # as we want multiple instances of vpn_wrapper.sh to be able to -# run simultaneously, we need unique ip addresses for them; -# the solution is to derive an ip address from current shell's -# PID (which is unique within a system) -NUMBER=$((($$ - 1) * 4)) -WORD0HOST0=$(($NUMBER % 256 + 1)) -WORD0HOST1=$(($NUMBER % 256 + 2)) -NUMBER=$(($NUMBER / 256)) -WORD1=$(($NUMBER % 256)) -NUMBER=$(($NUMBER / 256)) -WORD2=$(($NUMBER % 256)) -VETH_HOST0=10.$WORD2.$WORD1.$WORD0HOST0 -VETH_HOST1=10.$WORD2.$WORD1.$WORD0HOST1 +# run simultaneously, we need unique ip addresses for veth devices, which +# caller provides to us in command line arguments +VETH_HOST0="$3" +VETH_HOST1="$4" +# caller specifies space-delimited subnets, traffic to which should not be +# routed through the vpn (<database_ip>/32 is going to be here) +ROUTE_THROUGH_VETH="$5" + +# rest of args is the command to run in network namespace +for _ in `seq 5`; do + shift +done # to enable multiple instances of this script to run simultaneously, # we tag namespace name with this shell's PID |