25 lines
1.1 KiB
TeX
25 lines
1.1 KiB
TeX
\chapter{Security Proofs in Cryptography}
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Provable security is a subfield of cryptography where constructions are proven secure with regards to a security model.
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To illustrate this notion, let us take the example of public-key encryption schemes.
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This primitive consists in three algorithms:~key generation, encryption and decryption.
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These algorithms acts according to their names.
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Then, the question of ``how to define the security of this set of algorithms'' rises.
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To answer this question, we have to define the power of the adversary, and its goal.
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To model those two notions, cryptographers uses security games.
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% Security Reductions %
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\section{Security Reductions}
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Provable security focuses on providing constructions for which the security is guaranteed by a security proof, or security reduction.
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These proofs consist in polynomial reductions from difficult problems: the hardness assumptions.
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The quality of a proof depends on the security of the hardness assumption, and the tightness of the proof.
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\section{Random-Oracle Model and Standard Model}
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