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It does not apply here, but strcmp is, due to the early bailout that any sane implementation uses, suspectible to timing attacks, as in http://www.cs.rice.edu/~scrosby/slides/SCISS-latency.1.ppt.

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A timing attack against URL query strings as processed by a normalizing cache proxy?

Quoth the parent: "It does not apply here"

Sure. The flaw here isn't strcmp. In fact, most crypto compares don't use strcmp, even in naive code; an HMAC-SHA1 MAC, for instance, is an array of 8-bit bytes, not the hex string that programs encode them into for human consumption. "memcmp" is the normal culprit.

Timing attacks aren't a flaw in memcmp or strcmp. Touching every byte of a string is stupid behavior in the overwhelming majority of cases.

Unless, of course, you're Nintendo: http://wiibrew.org/wiki/Signing_bug

Good find. Again, notice how the problem here isn't strcmp or it's timing behavior; it's mistakenly using ASCIIZ strings to hold ciphertext.

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