Tweakable Block Ciphers
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TLDR
This work formalizes a cryptographic primitive, the “tweakable block cipher,” and suggests that tweakable block ciphers are easy to design, the extra cost of making a block cipher “Tweakable” is small, and it is easier to design and prove the security of applications of blockciphers that need this variability using tweakable blocks.Abstract:
A common trend in applications of block ciphers over the past decades has been to employ block ciphers as one piece of a “mode of operation”—possibly, a way to make a secure symmetric-key cryptosystem, but more generally, any cryptographic application. Most of the time, these modes of operation use a wide variety of techniques to achieve a subgoal necessary for their main goal: instantiation of “essentially different” instances of the block cipher.
We formalize a cryptographic primitive, the “tweakable block cipher.” Such a cipher has not only the usual inputs—message and cryptographic key—but also a third input, the “tweak.” The tweak serves much the same purpose that an initialization vector does for CBC mode or that a nonce does for OCB mode. Our abstraction brings this feature down to the primitive block-cipher level, instead of incorporating it only at the higher modes-of-operation levels. We suggest that (1) tweakable block ciphers are easy to design, (2) the extra cost of making a block cipher “tweakable” is small, and (3) it is easier to design and prove the security of applications of block ciphers that need this variability using tweakable block ciphers.read more
Citations
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[서평]「Applied Cryptography」
TL;DR: The objective of this paper is to give a comprehensive introduction to applied cryptography with an engineer or computer scientist in mind on the knowledge needed to create practical systems which supports integrity, confidentiality, or authenticity.
Journal ArticleDOI
Lest we remember: cold-boot attacks on encryption keys
J. Alex Halderman,Seth D. Schoen,Nadia Heninger,William Clarkson,William Paul,Joseph A. Calandrino,Ariel J. Feldman,Jacob Appelbaum,Edward W. Felten +8 more
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Compact Proofs of Retrievability
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Journal ArticleDOI
Compact Proofs of Retrievability
Hovav Shacham,Brent Waters +1 more
TL;DR: The first proof-of-retrievability schemes with full proofs of security against arbitrary adversaries in the strongest model, that of Juels and Kaliski, are given.
References
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Book
Handbook of Applied Cryptography
TL;DR: A valuable reference for the novice as well as for the expert who needs a wider scope of coverage within the area of cryptography, this book provides easy and rapid access of information and includes more than 200 algorithms and protocols.
[서평]「Applied Cryptography」
TL;DR: The objective of this paper is to give a comprehensive introduction to applied cryptography with an engineer or computer scientist in mind on the knowledge needed to create practical systems which supports integrity, confidentiality, or authenticity.
Journal ArticleDOI
How to construct pseudorandom permutations from pseudorandom functions
Michael Luby,Charles Rackoff +1 more
TL;DR: Any pseudorandom bit generator can be used to construct a block private key cryptos system which is secure against chosen plaintext attack, which is one of the strongest known attacks against a cryptosystem.
Journal ArticleDOI
Password security: a case history
Robert Morris,Ken Thompson +1 more
TL;DR: The present design of the password security scheme was the result of countering observed attempts to penetrate the system and is a compromise between extreme security and ease of use.
BookDOI
Applied cryptography, second edition : protocols, algorithms,and source code in C
TL;DR: Part I—Cryptographic Protocols Chapter 2—Protocol Building Blocks 2.