INT-RUP Analysis of Block-cipher Based Authenticated Encryption Schemes

Analysis of One-pass Block Cipher Based Authenticated Encryption Schemes

COFFE: Ciphertext Output Feedback Faithful Encryption On-Line Authenticated Encryption Without a Block Cipher

In this paper we introduce the first authenticated encryption scheme based on a hash function, called COFFE. This research has been motivated by the challenge to fit secure cryptography into constrained devices – some of these devices have to use a hash function, anyway, and the challenge is to avoid the usage of an additional block cipher to provide authenticated encryption. COFFE satisfies th...

The INT-RUP Security of OCB with Intermediate (Parity) Checksum

OCB is neither integrity under releasing unvierified plaintext (INT-RUP) nor nonce-misuse resistant. The tag of OCB is generated by encrypting plaintext checksum, which is vulnerable in the INT-RUP security model. This paper focuses on the weakness of the checksum processing in OCB. We describe a new notion, called plaintext or ciphertext checksum (PCC), which is a generalization of plaintext c...

How to Securely Release Unverified Plaintext in Authenticated Encryption

Scenarios in which authenticated encryption schemes output decrypted plaintext before successful verification raise many security issues. These situations are sometimes unavoidable in practice, such as when devices have insufficient memory to store an entire plaintext, or when a decrypted plaintext needs early processing due to real-time requirements. We introduce the first formalization of the...

CPA on COLM Authenticated Cipher and the Protection Using Domain-Oriented Masking

Authenticated encryption schemes are important cryptographic primitives that received extensive attention recently. They can provide both confidentiality and authenticity services, simultaneously. Correlation power analysis (CPA) can be a thread for authenticated ciphers, similar to the any physical implementation of any other cryptographic scheme. In this paper, a three-step CPA attack against...