dhcpd.conf and omapi-key question

[Mikolaj Kucharski]

Hi,

I've configured dhcpd(8) with omapi port enabled:

	% /etc/dhcpd.conf
	...
	omapi-port 7911;
	omapi-key omapi_key;

	key omapi_key {
		algorithm hmac-md5;
		secret XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX==;
	}
	...

Various resources found on the net, as well as the dhcpd.conf(5) manual
page describe generation of the keys with dnssec-keygen, or dns-keygen
which I think can be done in much simpler way. Example command from
dhcpd.conf(5) manual page which generates 128 bit secret key:

	% dnssec-keygen -a HMAC-MD5 -b 128 -n USER DHCP_UPDATER

Can someone confirm that this secret key is just random data, and can be
generated with any tool like OpenSSL and copy-pasted to the dhcpd(8)
config file? Example of 512 bit key generation with openssl(1):

	% openssl rand -base64 64 | tr -d '\n'; echo

Could someone explain that they key doesn't depend any way on the
algorithm used in above config example?

Are there any key requirements for hmac-md5?


Details of my system:

	% rpm -q dhcp centos-release
	dhcp-3.0.5-13.el5
	centos-release-5-2.el5.centos

-- 
best regards
q#