Link account created with cakephp project and cname

Hello, We have create a new project with cakephp and we are creating reseller option. Every reseller can have their own domain, who will be linked to our solution. And we need to link the domain of our reseller with our solution by Cname. We need a help to link it if we need to add something only on the php code or on the linux server working with centos and whm/cpanel.