With good design for radio self-interference isolation and cancellation, full-duplex radio promises to be feasible for real world applications. One of the important applications is secure communication since such a radio can receive information from a desired source while it also transmits jamming noise to eavesdroppers at the same time and same frequency. This paper considers a three-node multicarrier network consisting of a source, a full-duplex destination and an eavesdropper where the source and destination both apply power distributions to maximize the secrecy capacity against the eavesdropper. Fast algorithms feasible for real-time applications are developed to achieve the maximum secrecy capacity subject to both power constraint and source-to-destination rate constraint.