slimDHCP

A very slim DHCP server

Running

sudo python slimDHCP.py --interface=ens4u1 --cache_db=session.json --filter_clients='{"00:00:00:00:00:01" : "192.168.1.5"}'

Notes

Requires Linux and Python3.3+.
There are some defaults if no options are given:

• subnet 192.168.1.0
• netmask 255.255.255.0
• gateway <subnet>.1 (first avail in subnet)
• dns_servers 8.8.8.8 and 4.4.4.4

Parameters

All parameters must be JSON compliant.
This in order for json.loads() to parse some of them.

	--cache_dir='./'
	--cache_db=null
	--subnet="192.168.1.0" ("192.168.1.0/24" is also valid and thus --netmask is ignored)
	--netmask="255.255.255.0" (/24 is also valid)
	--gateway=null (takes first available host from subnet definition)
	--is_gateway=false (more details below)
	--dns_servers="8.8.8.8,4.4.4.4" (json compliant string required)
	--pxe_bin=null
	--pxe_dir='./'
	--pxe_config=null
	--filter_clients='{"de:ad:be:ef:00:01" : true, "de:ad:be:ef:00:02" : "192.168.1.10"}'

There are some special flags, one such flag is --is_gateway. --is_gateway=false simply tells slimDHCP that we're not the gateway, and thus won't give out a DHCP lease to our own MAC even if we tried.
However, if we set --is_gateway=true and our local interface sends a DHCP request, we will hand out a lease to ourselves. See false as a passive mode. And in both cases, the gateway ip is reserved and won't be given out.