Client API ---------- Basically the Authen::SASL module gathers some info. When ->client_new is called the plugin is called to create a $conn object. At that point it should query the Authen::SASL object for mechanisms and callbacks Properties are then set on the $conn object by calling $conn->property Then client_start is called Then we call client_step with a challenge string to get a response string. need_step can be called to check that this step is actually necessary for the selected mechanism. Quite simple really I think. So the plugin just needs to support client_new client_start client_step need_step # returns true if client_step needs to be called property # set/get for properties mechanism # returns the name of the chosen mechanism service # the service name passed to client_new host # the hostname passed to client_new is_success # returns true if authentication suceeded Server API ---------- The server API is symetric to the client's one. server_new is called to create a connection object. Then server_start is called, and if relevant the first data from the client is passed to it as argument. Then we call server_step with all the response from the clients, which returns challenges. need_step also determines if the current mechanism requires another step. So the plugin just needs to support server_new server_start server_step need_step # returns true if client_step needs to be called property # set/get for properties mechanism # returns the name of the chosen mechanism service # the service name passed to client_new host # the hostname passed to client_new is_success # returns true if authentication suceeded Callbacks --------- properties and callbacks are passed by name, so you will need to convert them to numbers. There are three types of call back user => 'fred' When the user callback is called, it will just return the string 'fred' user => \&subname When the user callback is called, &subname will be called and it will be passed the $conn object as the first argument. user => [ \&subname, 1, 2, 3] When the user callback is called, &subname will be called. It will be passed the $conn object, followed by all other values in the array