Theoretical analysis of symmetric cryptographic primitives and cryptographic hash functions.

The goal of this project is to build a solid theoretical framework for the formal security definitions of symmetric cryptographic primitives and cryptographic hash function. The work encompasses generic and specific security definitions for symmetric primitives, such as block ciphers and message authentication codes, keyless and keyed, salted or tweaked hash functions in both standard and idealized setting. It will establish property relations and separations by means of reductionist proofs and counterexamples, and link the definitions to concrete cryptographic structures and applications satisfying the desired security goal. In addition, we aim to provide a broad methodology for the reductionist security analysis of various existing and new hash function structures. The definitional framework we introduced in the previous section will facilitate identifying the properties of the hash funciton and its components. Then, we will investigate concrete hash function structures and analyze their reductionis security, preferably in the standard model. Where positive provable security results are not reachable, we will attempt impossibility proofs. In a final step, we will provide generalizations of the functional security characteristics required from the building blocks to attain a target security level from the hash function.

Keywords:Reductionist security analysis, Security definitions, Hash functions

Disciplines:Other engineering and technology