Instruction Change: xc.aessub enc rot

scarv / xcrypto

XCrypto: a cryptographic ISE for RISC-V

MIT License

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Instruction Change: xc.aessub enc rot #78

Open phthinh opened 5 years ago

phthinh commented 5 years ago

It should be more useful if this xc.aessub.encrot performs SBOX and byte right rotation instead of left rotation. So that, it can be used effectively in key expansion function.

danpage commented 5 years ago

I just checked through this, and I think you're right: it seems the mismatch might have stemmed from the fact the original paper used a big-endian, SPARC-based platform. So their left-rotate should be a right-rotate for a little-endian RISC-V?