baseConvert() & 32-bit ops

[Mark Brownell]

On Monday, June 23, 2003, at 08:36  AM, Mark Brownell wrote:

> That will be easy to test for, The + 1 and the - 1 are in regards to 
> one of the 256 positions  in the S-boxes. I'm starting to talk like a 
> max zoomed dweeb...

oops...

the -1 is in regards to the bitAnd part of the f function's S-boxes.

>>     f = S1[a] + S2[b]
>>     f = bitXor( f , S3[c] )
>>     f = bitAnd( f + S4[d], -1 )

[snip]

> You should challenge my speculation.  You can use "the long seconds" 
> to time operations.  Time a simple xor and time getting a value from 
> an array with 256 numerical entries and see how they compare.  Time 
> your half block swap, too, to get a reference point.
>
> Dar

I will test everything that I can test differences for. One of the 
problems is that to xor some numbers I must get a number from an array 
to use as part of the xor first. In my own way of looking at this I 
have related the f function to being descriptive of why they call them 
S-boxes in the first place. All this zigging, replacing, zagging, 
replacing, and exchanges based on unique key regeneration is 
fascinating. I'm tempted to get that highly recommended book that you 
referenced.

Mark
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