On 2007-05-10 00:23:50 +0200, Johannes Schindelin wrote: > I was not aware originally, that no arithmetic is involved in SHA-1 > computation. > > If you store large integers, it makes tons of sense to follow the > endianness, especially if you do _both_ boolean and integer > operations on them. Actually, if you take a look at http://en.wikipedia.org/wiki/Sha1#SHA-1_algorithm you'll see that in addition to an unholy mess of bitwise operations, it does do some additions, on 32-bit big-endian words according to the article. But thinking of them as addition gives you the wrong mental picture; they're simply one of many ways for a standard processor to mix bits efficiently as far as SHA-1 is concerned. The algorithm is specified as yielding a 160-bit binary blob, and can and should be thought of as a black NSA-certified box with "warranty void if this seal is broken" stickers. (Unless you're the one implementing it, of course. But then you know what you're doing.) -- Karl Hasselström, kha@xxxxxxxxxxx www.treskal.com/kalle - To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
