Can someone explain and/or direct me to a summary of the variables that are available to be passed to OpenVPN upon a client connection?
For example, what do the following $1, $2, $3, $4 values produce for variables:
ip=$1
user=$2
?=$3
?=$4
?=$5
etc
To clarify: when a user connects to OpenVPN the following learn-address script is called (please see below)
I would like to know what variables are available to pass to this bash script once a user connects
Here is the learn-address script and the first (2) variables (at the top of the script) $1 and $2 – are there other variables we can capture (eth0 vs dev1, etc)?
#!/bin/bash
statedir=/tmp/
function bwlimit-enable() {
ip=$1
user=$2
# Disable if already enabled.
bwlimit-disable $ip
# Find unique classid.
if [ -f $statedir/$ip.classid ]; then
# Reuse this IP's classid
classid=`cat $statedir/$ip.classid`
else
if [ -f $statedir/last_classid ]; then
classid=`cat $statedir/last_classid`
classid=$((classid+1))
else
classid=1
fi
echo $classid > $statedir/last_classid
fi
# Find this user's bandwidth limit
# downrate: from VPN server to the client
# uprate: from client to the VPN server
if [ "$user" == "myuser" ]; then
downrate=10mbit
uprate=10mbit
elif [ "$user" == "anotheruser"]; then
downrate=2mbit
uprate=2mbit
else
downrate=5mbit
uprate=5mbit
fi
# Limit traffic from VPN server to client
tc class add dev $dev parent 1: classid 1:$classid htb rate $downrate
tc filter add dev $dev protocol all parent 1:0 prio 1 u32 match ip dst $ip/32 flowid 1:$classid
# Limit traffic from client to VPN server
tc filter add dev $dev parent ffff: protocol all prio 1 u32 match ip src $ip/32 police rate $uprate burst 80k drop flowid :$classid
# Store classid and dev for further use.
echo $classid > $statedir/$ip.classid
echo $dev > $statedir/$ip.dev
}
function bwlimit-disable() {
ip=$1
if [ ! -f $statedir/$ip.classid ]; then
return
fi
if [ ! -f $statedir/$ip.dev ]; then
return
fi
classid=`cat $statedir/$ip.classid`
dev=`cat $statedir/$ip.dev`
tc filter del dev $dev protocol all parent 1:0 prio 1 u32 match ip dst $ip/32
tc class del dev $dev classid 1:$classid
tc filter del dev $dev parent ffff: protocol all prio 1 u32 match ip src $ip/32
# Remove .dev but keep .classid so it can be reused.
rm $statedir/$ip.dev
}
# Make sure queueing discipline is enabled.
tc qdisc add dev $dev root handle 1: htb 2>/dev/null || /bin/true
tc qdisc add dev $dev handle ffff: ingress 2>/dev/null || /bin/true
case "$1" in
add|update)
bwlimit-enable $2 $3
;;
delete)
bwlimit-disable $2
;;
*)
echo "$0: unknown operation [$1]" >&2
exit 1
;;
esac
exit 0
Best Answer
The $1, $2, and $3 are the arguments passed to the script, that are documented in the man page.