Alibaba Group Holding Limited
PREVENTING MISREPRESENTATION OF INPUT DATA BY PARTICIPANTS IN A SECURE MULTI-PARTY COMPUTATION

Abstract:

Disclosed herein are methods, systems, and apparatus, including computer programs encoded on computer storage media, for secure multi-party computation. One of the methods includes identifying a trusted input data item that is homomorphically encrypted; generating a message authentication code (MAC) key share; generating a MAC share associated with the trusted input data item, wherein the MAC share is a random number; generating a ciphertext based on the trusted input data item, the MAC key share, and the MAC share; sending the ciphertext to the second computing device, wherein the second computing device uses the ciphertext as a component of a MAC share associated with the secret input data item; and after the multi-party computation is completed by the plurality of computing devices, verifying a result of the multi-party computation based at least in part on the MAC share associated with the secret input data item.