D4.10 Annual Report on: Information-leakage analysis and countermeasure Y2

In this report, we propose one possible counter-measure to the inherent leakage of functional encryption schemes in the multi-input setting. More precisely, we consider the use of labels during the encryption procedure to limit the amount of possible mix-and-match that can take place during decryption. In particular, when encryption labels are used, the user in possession of a functional decryption key will only be able to decrypt ciphertexts that were generated with respect to the same label.