Hi Everyone, I want to investigate variable size block ciphers, and the changes required to support them.
The immediate pain point is the class constant BLOCKSIZE, which becomes a moving target. That could be worked around with MINIMUM_BLOCKSIZE, MAXIMUM_BLOCKSIZE, and making BLOCKSIZE a sane default, similar to the way keys are described. Or, we could signal that Blocksize() must be used by making BLOCKSIZE equal to 0xffffffff. A quick/small survey of Rijndael, Threefish and Kalyna indicate its not a straight forward VariableBlockSize<...> implemented like VariableKeyLength<...>. In the case of Threefish, the block sizes are 256, 512 and 1024; 768 is absent. In the case of Kalyna, the block size is either (1) equal to the key size; or (2) twice the key size. I'm guessing there are more novel schemes out there. I'm also guessing we are going to need to accept a good fit because a perfect fit probably does not exist. A good fit would allow VariableBlockSize<...> with the knowledge we have some extra work to do, and Blocksize() must be used at runtime for an accurate accounting. Does anyone have implementation experience or thoughts on it? Jeff -- -- You received this message because you are subscribed to the "Crypto++ Users" Google Group. To unsubscribe, send an email to cryptopp-users-unsubscr...@googlegroups.com. More information about Crypto++ and this group is available at http://www.cryptopp.com. --- You received this message because you are subscribed to the Google Groups "Crypto++ Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to cryptopp-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
