Bitstream Modification of Trivium

Kalle Ngo; Elena Dubrova; Michail Moraitis

Paper 2020/597

Bitstream Modification of Trivium

Kalle Ngo, Elena Dubrova, and Michail Moraitis

Abstract

In this paper we present a bitstream modification attack on the Trivium cipher, an international standard under ISO/IEC 29192-3. By changing the content of three LUTs in the bitstream, we reduce the non-linear state updating function of Trivium to a linear one. This makes it possible to recover the key from 288 keystream bits using at most $2^{19.41}$ operations. We also propose a countermeasure against bitstream modification attacks which obfuscates the bitstream using dummy and camouflaged LUTs which look legitimate to the attacker. We present an algorithm for injecting dummy LUTs directly into the bitstream without causing any performance or power penalty.

Metadata

Available format(s): PDF
Category: Secret-key cryptography
Publication info: Preprint. MINOR revision.
Keywords: FPGA reverse engineering bitstream modification fault injection stream cipher Trivium
Contact author(s): kngo @ kth se
dubrova @ kth se
micmor @ kth se
History: 2020-05-22: received
Short URL: https://ia.cr/2020/597
License: CC BY

BibTeX

@misc{cryptoeprint:2020/597,
      author = {Kalle Ngo and Elena Dubrova and Michail Moraitis},
      title = {Bitstream Modification of Trivium},
      howpublished = {Cryptology {ePrint} Archive, Paper 2020/597},
      year = {2020},
      url = {https://eprint.iacr.org/2020/597}
}