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I am conducting a research on cpu-cache based info leak caused by using Sliding window in the diffie helman key exchange.

For my research I am looking for a real-world implementation of sliding window,I have read the source of BouncyCastle and Gnu-TLs and came out empty.

Can someone share some light on the real world use of this algorithm and where, if at all I will be able to find implementation of it?

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Serious cryptography software today does not use sliding windows for exponentiation by secrets precisely because it leaks the secrets through array indexing. You might find it older versions of OpenSSL, libgcrypt, etc. In modern software, your best bet is probably libgmp (mpz_powm, not mpz_powm_sec) or other generic bignum libraries optimized for speed, not for security.

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PolarSSL / ARM mbedTLS is still using sliding window exponentiation in its RSA implementation. This library is used (and recommended) for many performance and power-constrained embedded systems. However, mbedTLS additionally uses exponent blinding as a countermeasure, supposed to be effective against realistic cache timing side-channel attacks.

If you start looking at literature, please be aware of differences between power side-channels (typically a local attacker who measures power with an oscilloscope), and timing side-channels (typically another user that has partial software access on the system and uses cache-timing side-channels).

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