Homomorphic Exclusive-Or Operation Enhance Secure Searching on Cloud Storage

Enterprise cloud tenants would store their outsourced cloud data in encrypted form for data privacy and security. However, flexible data access functions such as data searching is usually sacrificed as a result. Thus, enterprise tenants demand secure data retrieval and computation solution from the cloud provider, which will allow them to utilize cloud services without the risks of leaking private data to outsiders and even service providers. In this paper, we propose an exclusive-or (XOR) homomorphism encryption scheme to support secure keyword searching on encrypted data. First, this scheme specifies a new data protection method by encrypting the data and randomizing it by performing XOR operation with a random bit-string. Second, this scheme can effectively protect data-in-transit against passive attack such as cipher text analysis due to the randomization. Third, this scheme is lightweight and only requires a symmetric encryption scheme and bitwise operations, which requires processing time in the order of milliseconds.