[ccache] Questions about two hot functions in ccache

[Martin Pool]

On 20 October 2010 08:15, Joel Rosdahl <joel at rosdahl.net> wrote:
> MD4 has been there from the start and neither Tridge or I have seen any
> reason to switch it. MD5, SHA1 and other even more modern cryptograhic
> hash functions are indeed stronger but also slower, and the increased
> resistance against various crypto attacks doesn't seem necessary in a
> tool like ccache. That said, I'm sure there nowadays may exist hash
> functions that are both better (i.e., with lower collision rate) AND
> faster than MD4. Do you (or anyone else) know of any with properties
> that would be a good fit for ccache?

I think any of the cryptographic hash functions will have an even
distribution of outputs, so nothing else will give stronger resistance
to accidental collision.  The only problem with MD4 is that it might
be vulnerable to malicious collisions (which seems pointless in ccache
as it currently exists) and that others might be faster.

-- 
Martin