Re: sha1, sha2 functions into core? - Mailing list pgsql-hackers

From Greg Sabino Mullane
Subject Re: sha1, sha2 functions into core?
Date
Msg-id 844dc3ff5a7fc13d0fe665a9666e06fa@biglumber.com
Whole thread Raw
In response to Re: sha1, sha2 functions into core?  (Merlin Moncure <mmoncure@gmail.com>)
Responses Re: sha1, sha2 functions into core?
List pgsql-hackers
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> If the hacker has access to the salt, then it will only slow 
> him/her down somewhat because the search will be have to be
> restarted for each password.

This. Further, anyone using MD5 or SHA* or any hash function for 
any serious storage of passwords is nuts, in this day and age. 
GPUs and rentable cloud computers means the ability to test billions 
of passwords per second is easy for anyone, salted or not.

The issue is not Postgres' internal use of MD5 for passwords - that's 
a red herring, as it is basically no more relatively secure/insecure 
versus any other hashing algorithm that is not designed to be 
slow (e.g. bcrypt, scrypt, PBKDF2). The issue is simply exposing a 
more useful day to day algorithm by default. Much of the world uses 
SHA instead of MD5 these days for all sorts of purposes.

So I am torn on this. On the one hand, having a few more things in core 
would be very nice, as it seems silly we have md5() as a builtin but 
sha256() requires a special module. But once you add sha* in, why not 
AES? Blowfish? Why not go the whole way and include some extremely 
useful ones such as bcrypt? At that point, we've deprecated pg_crypto 
and moved everything to core. Why I personally would love to see that 
someday (then we can boast "built-in crypto" :), I recognize that will 
be a very tough sell. So I will take the addition of whatever we can, 
including just a sha() as this thread asked for.

> 3) use a purposefully slow hashing function like bcrypt.
>
> but I disagree: I don't like any scheme that encourages use of low
> entropy passwords.

Perhaps off-topic, but how to do you figure that?

- -- 
Greg Sabino Mullane greg@turnstep.com
End Point Corporation http://www.endpoint.com/
PGP Key: 0x14964AC8 201208201849
http://biglumber.com/x/web?pk=2529DF6AB8F79407E94445B4BC9B906714964AC8
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