University of Luxembourg
The authors introduce the concept of Identity-Based Encryption (IBE) with master Key-Dependent Chosen-Plaintext (mKDM-sID-CPA) security. These are IBE schemes that remain secure even after the adversary sees encryption, under some initially selected identities, of functions of the master secret key(s). They, then propose a generic construction of Chosen-Ciphertext secure Key-Dependent encryption (KDM-CCA) schemes in the public key setting starting from mKDM-sID-CPA secure IBE schemes. This is reminiscent to the celebrated work by Canetti, Halevi and Katz on the traditional key-oblivious setting.