Re: Re[2]: [Haskell-cafe] Password hashing

Just to note, the comment about md5 is incorrect. I switched to SHA512 as you can see in the code. 2008/11/25 Thomas Hartman :

What does haskell cafe think of the following module for drop-in password hasing for webapps? Seem reasonable?

import Data.Digest.SHA512 (hash) import qualified Data.ByteString as B' import qualified Data.ByteString.Char8 as B

-- store passwords as md5 hash, as a security measure scramblepass :: String -> IO String scramblepass p = do etSalt <- try $ readFile "secure/salt" case etSalt of Left e -> fail errmsg Right s -> -- return . show . md5 . L.pack $ p ++ s return . B.unpack . B'.pack . hash . B'.unpack . B.pack $ p ++ s where errmsg = "scramblepass error, you probably need to create a salt file in secure/salt. This is used for \ \hashing passwords, so keep it secure. chmod u=r secure/salt, and make sure it's skipped \ \in version control commits, etc. A good way to generate a salt file is (e.g., on ubuntu) \ \writeFile \"secure/salt\" =<< ( strongsalt $ readFile \"/dev/urandom\")\ \You could also just type some random seeming text into this file, though that's not quite as secure.\ \Keep a backup copy of this file somewhere safe in case of disaster."

-- | eg, on ubuntu: strongsalt $ readFile "/dev/urandom" strongsalt :: IO String -> IO String strongsalt randomSource = return . salt' =<< randomSource where salt' = show . fst . next . mkStdGen . read . concat . map (show . ord) . take 10

2008/10/30 Bulat Ziganshin :

...

Hello Thomas,

Thursday, October 30, 2008, 3:32:46 PM, you wrote:

...

No salt, but apart from that, should be fine, right?

1) without salt, it's not serious - easily breaked by dictionary attack

2) afair, md5 isn't condidered now as cryptographic hash

-- Best regards, Bulat mailto:Bulat.Ziganshin@gmail.com