An E cient State Recovery Attack on X-FCSR-256
نویسندگان
چکیده
We describe a state recovery attack on the X-FCSR-256 stream cipher of total complexity at most 2. This complexity is achievable by requiring 2 output blocks with an amortized calculation e ort of at most 2 table lookups per output block using no more than 2 table entries of precomputational storage.
منابع مشابه
An Efficient State Recovery Attack on X-FCSR-256
We describe a state recovery attack on the X-FCSR-256 stream cipher of total complexity at most 2. This complexity is achievable by requiring 2 output blocks with an amortized calculation e ort of at most 2 table lookups per output block using no more than 2 table entries of precomputational storage.
متن کاملCryptanalysis of Selected Stream Ciphers
T he aim of this dissertation is to show some cryptanalytical results on a selection of stream ciphers. We have grouped theory and results into three main parts. The first part focuses on the FCSR-based constructions X-FCSR and F-FCSRH v3. For the X-FCSR family of stream ciphers we perform a severe state recovery attack. This attack works for both X-FCSR-128 and X-FCSR-256. We then develop a ge...
متن کاملX - FCSR : a new software oriented stream cipher based upon FCSRs - Full version -
Feedback with Carry Shift Registers (FCSRs) are a promising alternative to LFSRs in the design of stream cipher. The previous constructions based on FCSRs were dedicated to hardware applications [3]. In this paper, we will describe X-FCSR a family of software oriented stream cipher using FCSRs. The core of the system is composed of two 256-bits FCSRs. We propose two versions: X-FCSR-128 and X-F...
متن کاملX-FCSR - A New Software Oriented Stream Cipher Based Upon FCSRs
Feedback with Carry Shift Registers (FCSRs) are a promising alternative to LFSRs in the design of stream cipher. The previous constructions based on FCSRs were dedicated to hardware applications [3]. In this paper, we will describe X-FCSR a family of software oriented stream cipher using FCSRs. The core of the system is composed of two 256-bits FCSRs. We propose two versions: X-FCSR-128 and X-F...
متن کاملCryptanalysis of the F-FCSR Stream Cipher Family
This paper focuses on F-FCSR, a new family of stream ciphers proposed by Arnault and Berger at FSE 2005. It uses a non-linear primitive called the Feedback with Carry Shift Register (FCSR) as a building block. Its security relies on some properties of the 2-adic numbers. The F-FCSR family contains several stream ciphers, each of them proposing different features. First, we show a resynchronizat...
متن کامل