Paper 2020/1242
Improved (Related-key) Differential Cryptanalysis on GIFT
Fulei Ji and Wentao Zhang and Chunning Zhou and Tianyou Ding
Abstract
In this paper, we reevaluate the security of GIFT against differential cryptanalysis under both single-key scenario and related-key scenario. Firstly, we apply Matsui's algorithm to search related-key differential trails of GIFT. We add three constraints to limit the search space and search the optimal related-key differential trails on the limited search space. We obtain related-key differential trails of GIFT-64/128 for up to 15/14 rounds, which are the best results on related-key differential trails of GIFT so far. Secondly, we propose an automatic algorithm to increase the probability of the related-key boomerang distinguisher of GIFT by searching the clustering of the related-key differential trails utilized in the boomerang distinguisher. We find a 20-round related-key boomerang distinguisher of GIFT-64 with probability 2^-58.557. The 25-round related-key rectangle attack on GIFT-64 is constructed based on it. This is the longest attack on GIFT-64. We also find a 19-round related-key boomerang distinguisher of GIFT-128 with probability 2^-109.626. We propose a 23-round related-key rectangle attack on GIFT-128 utilizing the 19-round distinguisher, which is the longest related-key attack on GIFT-128. The 24-round related-key rectangle attack on GIFT-64 and 22-round related-key boomerang attack on GIFT-128 are also presented. Thirdly, we search the clustering of the single-key differential trails. We increase the probability of a 20-round single-key differential distinguisher of GIFT-128 from 2^-121.415 to 2^-120.245. The time complexity of the 26-round differential attack on GIFT-128 is improved from 2^124:415 to 2^123:245.
Metadata
- Available format(s)
- Category
- Secret-key cryptography
- Publication info
- Published elsewhere. Minor revision. SAC 2020
- Keywords
- Matsui's algorithmRelated-key differential trailSingle-key differential trailClustering effectBoomerang attackRectangle attackGIFT
- Contact author(s)
- jifulei @ iie ac cn
- History
- 2020-10-30: revised
- 2020-10-09: received
- See all versions
- Short URL
- https://ia.cr/2020/1242
- License
-
CC BY