Hierarchical identity-based chameleon hash and its applications

• Main Authors: BAO, Feng, DENG, Robert H., DING, Xuhua, LAI, Junzuo, ZHAO, Yunlei
• Format: text
• Language: English
• Published: Institutional Knowledge at Singapore Management University 2011
• Subjects: Chameleon Hash; Trapdoor Sanitizable Signature; Hierarchical Identity-Based Chameleon Hash; Hierarchical Trapdoor Sanitizable Signature; Information Security
• Online Access: https://ink.library.smu.edu.sg/sis_research/1417; https://ink.library.smu.edu.sg/context/sis_research/article/2416/viewcontent/Bao2011_Chapter_HierarchicalIdentity_BasedCH_pv.pdf
• Institution: Singapore Management University

At ACNS 2008, Canard et al. introduced the notion of trapdoor sanitizable signature (TSS) based on identity-based chameleon hash (IBCH). Trapdoor sanitizable signatures allow the signer of a message to delegate, at any time, the power of sanitization to possibly several entities who can modify predetermined parts of the message and generate a new signature on the sanitized message without interacting with the original signer. In this paper, we introduce the notion of hierarchical identity-based chameleon hash (HIBCH), which is a hierarchical extension of IBCH. We show that HIBCH can be used to construct other cryptographic primitives, including hierarchical trapdoor sanitizable signature (HTSS) and key-exposure free IBCH. HTSS allows an entity who has the sanitization power for a given signed message, to further delegate its power to its descendants in a controlled manner. Finally, we propose a concrete construction of HIBCH and show that it is t-threshold collusion-resistant.