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Abstract Heresies · 1mo · discuss

Back in the 80s, Bob Baldwin was hacking cryptography at MIT and one hack he built was a streamlined DES implementation which tried to trim as many clock cycles as possible to do a DES encryption. Unix machines were using a salted DES password hashing scheme with a hardcoded constant of 64 zero bits that was encrypted 25 times. In traditional Unix crypt(3), the salt—a 12-bit value derived from a 2-character ASCII string—permutes the expansion function E in the DES algorithm, swapping 24 bits of the round expansion so that hardware DES chips couldn't be used to accelerate password cracking....