sasl_authorize_t() is a typedef function prototype that defines the interface associated with the SASL_CB_PROXY_POLICY callback.
Use the sasl_authorize_t() interface to check whether the authorized user auth_identity can act as the user requested_user. For example, the user root may want to authenticate with root's
credentials but as the user tmartin, with all of tmartin's rights, not root's. A server application should be very careful when it determines which users may proxy as other users.
The SASL connection context.
The identity or username to authorize. requested_user is null-terminated.
The length of requested_user.
The identity associated with the secret. auth_identity is null-terminated.