Paper 2019/418

Sharing of Encrypted files in Blockchain Made Simpler

S. Sharmila Deva Selvi, Arinjita Paul, Siva Dirisala, Saswata Basu, and C. Pandu Rangan


Recently, blockchain technology has attracted much attention of the research community in several domains requiring transparency of data accountability, due to the removal of intermediate trust assumptions from third parties. One such application is enabling file sharing in blockchain enabled distributed cloud storage. Proxy re-encryption is a cryptographic primitive that allows such file sharing by re-encrypting ciphertexts towards legitimate users via semi-trusted proxies, without them learning any information about the underlying message. To facilitate secure data sharing in the distributed cloud, it is essential to construct efficient proxy re-encryption protocols. In this paper, we introduce the notion of proxy self re-encryption (SE-PRE) that is highly efficient, as compared to the existing PRE schemes in the literature. We show that our self encryption scheme is provably CCA secure based on the DLP assumption and our proxy re-encryption scheme with self encryption is CCA secure under the hardness of the Computational Diffie Hellman (CDH) and Discrete Logarithm (DLP) assumption. Our novel encryption scheme, called self encryption, has no exponentiation or costly pairing operation. Even the re-encryption in SE-PRE does not have such operations and this facilitates the service provider with efficiency gain.

Available format(s)
Public-key cryptography
Publication info
Published elsewhere. MAJOR revision.The 1st International Conference on Mathematical Research for Blockchain Economy (Marble 2019)
blockchainproxy re-encryptionself-encryptionCCAcloud storage
Contact author(s)
arinjita paul @ gmail com
sharmioshin @ gmail com
prangan55 @ gmail com
2019-04-24: received
Short URL
Creative Commons Attribution


      author = {S.  Sharmila Deva Selvi and Arinjita Paul and Siva Dirisala and Saswata Basu and C.  Pandu Rangan},
      title = {Sharing of Encrypted files in Blockchain Made Simpler},
      howpublished = {Cryptology ePrint Archive, Paper 2019/418},
      year = {2019},
      note = {\url{}},
      url = {}
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