updated

README.md

 A userspace application that filters DHCP floods to protect a DHCP server. It uses the Netfilter userspace packet queuing API.
 
 # Dependencies
-build-essential uthash-dev libnetfilter-queue-dev
+```
+apt-get install build-essential uthash-dev libnetfilter-queue-dev
+```
+# Configuration
+```
+# max_pkt_per_interval
+# maximum number of packets authorised per time interval.
+max_pkt_per_interval=30
+
+# interval
+# measurement time interval in seconds.
+interval=30
+
+# debug
+# enable debugging, warning, very verbose
+debug=1
+
+# blacklist_time
+# number of seconds this client will be ignored once
+# it exceeded the max_pkt_per_interval per interval
+blacklist_time=55
+
+# queue number
+# refers to the queue-num of iptables.
+# -A FORWARD -p udp -m udp --dport 67 -j NFQUEUE --queue-num 67 --queue-bypass
+queue=67
+
+# dryrun
+# if dryrun is set to 1 it will accept all packets no matter what.
+# this can be used for testing, syslog will still display the blacklisting
+# actions.
+# Set to 0 for production.
+dryrun=1
+```
+
+# Run
+```
+root@router:~/dhcp_protect# ./dhcp_protect ./dhcp_protect.conf
+Loading configuration ./dhcp_protect.conf
+Configuration:
+	dryrun               =  Yes
+	debug                =  Yes
+	interval             =   30s
+	max_pkt_per_interval =   30
+	blacklist_time       =   55s
+	queue                =   67
+```