Questions tagged [bitslicing]
For questions about bitsliced (SIMD-within-a-register / SWAR) implementation of ciphers and other cryptographic primitives.
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Getting bit length of exponentiation result before computation
I'm working in a context where it is cheaper to calculate pow(a,b) via modular exponentiation (modexp(a,b,m)) than to do ...
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Security of bitsliced AES with a transposition step omitted
Suppose you take the aes_sub_bytes function intended to operate on 4 aes blocks which were bitsliced to 8 u64's but you omit the bitslicing step beforehand. As a result you apply the sbox to the ...
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DES SBOX Output with Bitslice
I am not understanding how to compute the output bits of a 6-to-4-SBOX with bitslice technique in DES.
Matthew Kwan made a brief recap in his paper "Reducing the Gate Count of Bitslice DES" ...
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How do byte-sliced AES implementations work?
While I understand the principle of bit-slicing, several papers mention byte-sliced AES implementations (see e.g. Homomorphic Evaluation of the AES Circuit and Fast Implementations of AES on Various ...
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Bit slice format of 4x4 s-boxes?
I have studied bit-sliced implementation in SERPENT block cipher and I need to use this technique to implement some 4x4 s-boxes. I couldn't find any procedure to obtain bit-sliced format in any paper ...
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Ideal way to profile/performance-measure cipher implementations
I have implemented a bit-sliced version of two ciphers (Gibbon-120 and Hanuman-120, both part of the Primates family of ciphers: http://primates.ae/wp-content/uploads/primatesv1.02.pdf )
I now want ...
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How do Käsper and Schwabe's Bitsliced AES Mixcolumns work?
The only way I see it possible to do the matrix-multiplication in the MixColumns operation of AES is by shifting the bits in the multiplied number, and then reduce with the polynomial if needed.
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How can bit slicing be constant time, when Mix Columns is in the cipher
I'm reading about bit-slicing techniques, and one thing about it caught my mind.
The strength with bit sliced implementations are (apart from that they are fast) that they are running in constant ...
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Converting a 5-bit s-box to its bit-sliced format
I'm currently trying to convert a 5-bit sbox (the one from this cipher: http://primates.ae/wp-content/uploads/primatesv1.02.pdf) to its bit-sliced format (i.e. to a boolean network).
Most papers ...
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Can GCM auth be bitsliced?
Is it possible to use bitslicing for GCM? This seems like a way to allow for a way to avoid cache-timing attacks without PCLMUL instructions and with good performance.
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How is bitslicing faster?
I have read a paper on Bit Slicing and Lightweight crypto but cannot understand how bitslicing makes encryption scheme faster.
Please can someone explain with an example exactly how bit slicing makes ...
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Serpent block cipher : S0 to S7 functions unclear
I am presently implementing the serpent block cipher in C++ following the specifications. It's important to mention that I'm implementing the cipher in bitslice mode. You'll need the The full ...
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