Atom: A Stream Cipher with Double Key Filter

Banik, Subhadeep; Caforio, Andrea; Isobe, Takanori; Liu, Fukang; Meier, Willi; Sakamoto, Kosei; Sarkar, Santanu

doi:10.46586/tosc.v2021.i1.5-36

Cited by 3 publications

(1 citation statement)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The contributions in this paper can be summarised as follows: We report the first quantum implementation of the stream cipher Atom [31]. The construction of Atom makes use of a double key filter and also has slightly different functions during initialisation and the keystream generation phases.…”

Section: Introductionmentioning

confidence: 99%

Analysis of Atom against quantum attacks

Anand,

Nandi,

Isobe

2023

IET Quantum Communication

View full text Add to dashboard Cite

A significant amount of study is being done to review the security promises made for the various ciphers now in use as a result of the development of quantum computing technology. A general attack against symmetric key cryptography primitives that can reduce search costs to the square root is Grover's search algorithm. To implement Grover's algorithm, it is necessary that the target cipher be implemented as a quantum circuit. Despite being relatively new, this area of study has received significant attention from the research community. The authors have estimated the cost of Grover's key search attack against the stream cipher Atom, for the first time, under circuit depth restrictions defined in National Institute of Standards and Technology (NIST) PQC standardisation process. The authors implement the quantum circuit of Atom in QISKIT, (open‐source software development kit for working with quantum computers running on IBM Quantum Experience). The results are also compared with other existing literature on LFSR‐based stream ciphers, such as Grain‐v1, Grain‐128‐AEAD, and Lizard. The authors also find that, to the best of their knowledge, in the existing literature on estimating the cost of Grover's attack on symmetric ciphers, Atom is the only 128‐bit key cipher that meets the threshold of ≈2170 set by NIST for quantum security of 128‐bit key ciphers. The authors also analyse the security of Atom against quantum TMDTO attacks.

show abstract

Section: Introductionmentioning

confidence: 99%

Analysis of Atom against quantum attacks

Anand,

Nandi,

Isobe

2023

IET Quantum Communication

View full text Add to dashboard Cite

show abstract

Near Collision Attack Against Grain V1

Banik

Collins

Meier

2023

Lecture Notes in Computer Science

Self Cite

View full text Add to dashboard Cite

A near collision attack against the Grain v1 stream cipher was proposed by Zhang et al. in Eurocrypt 18. The attack uses the fact that two internal states of the stream cipher with very low hamming distance between them, produce similar keystream sequences which can be identified by simple statistical tests. Such internal states once found in the stream cipher simplify the task of cryptanalysis for the attacker. However this attack has recently come under heavy criticism from Derbez et al. at ToSC 2020:4, who claim that some of the assumptions made in the above paper were not correct. As a result they concluded that the attack presented by Zhang et al. when implemented would take time more than required for a brute force search. In this paper, we take another look at the near collision attack against the Grain v1 stream cipher. We avoid the techniques of the above Eurocrypt paper that have come under criticism, and independently show that a near collision attack can still be applied to Grain v1.

show abstract

Provable security against generic attacks on stream ciphers

Moch

2023

Journal of Mathematical Cryptology

View full text Add to dashboard Cite

Recent lightweight hardware-based stream cipher designs keep an external non-volatile internal state that is not part of the cipher’s hardware module. The purpose of these so-called small-state ciphers is to keep the size of the hardware and the power consumption low. We propose a random oracle model for stream ciphers. This will allow us to analyse the recent small-state stream cipher designs’ resistance against generic attacks and, in particular, time-memory-data tradeoff attacks. We analyse the conventional construction underlying stream ciphers like Grain and Trivium, constructions continuously using the external non-volatile secret key during keystream generation like Sprout, Plantlet, Fruit, and Atom, constructions continuously using the external non-volatile IV, and constructions using a combination of the IV and the key like DRACO. We show the tightness of all bounds by first presenting the time-memory-data tradeoff attacks on the respective constructions, establishing the upper bound on security, and then presenting the proof of security to establish the lower bound on security. In this work, we extend the theoretical work done by Hamann et al. who introduced the DRACO stream cipher at FSE 2023. We use the same random oracle model as the aforementioned work and apply it to the earlier work by Hamann et al. presented at SAC 2019, which showed security for two of the four constructions we consider in this work. Our model is equivalent but allows for a much simpler proof of security. Furthermore, we provide a proof of security for stream ciphers continuously using the secret key during keystream generation, giving upper and lower bounds for all four generic stream cipher constructions proposed so far.

show abstract

Atom: A Stream Cipher with Double Key Filter

Cited by 3 publications

References 35 publications

Analysis of Atom against quantum attacks

Analysis of Atom against quantum attacks

Near Collision Attack Against Grain V1

Provable security against generic attacks on stream ciphers

Contact Info

Product

Resources

About