Alexander Holler <[email protected]> writes: > Am 18.12.2009 02:33, schrieb Kurt Zeilenga: >> >> On Dec 17, 2009, at 9:55 AM, Simon Josefsson wrote: >> >>> Low iteration counts removes one nice features of SCRAM (mitigating >>> dictionary attacks on stolen hash databases). >> >> It's only a nice feature if you can take advantage of it. If you need to >> support multiple password mechanisms, each either their own hashed password, >> you'd end up storing each. And then the attacker need only attack the >> weakest. And with need to service providers to support DIGEST-MD5 and >> CRAM-MD5, to the most popular password-based mechanisms, the weakest is not >> much stronger than cleartext. > > Storing a hash for every mechanism will not work. E.g. for DIGEST-MD5 > the server has to hash the clear-text password with a value the client > provides.
That is true for CRAM-MD5, but not for DIGEST-MD5 and SCRAM-MD5. With the latter two mechanisms, the server can store a hash and perform authentications without access to the password. For CRAM-MD5 this is not possible, and the server indeed needs to have access to the cleartext password for things to work. > So the server needs the clear-text password. And if the server is able > to get the clear-text password, everyone with the same rights on the > server can retrieve the clear-text passwords too. Right. /Simon _______________________________________________ JDev mailing list Forum: http://www.jabberforum.org/forumdisplay.php?f=20 Info: http://mail.jabber.org/mailman/listinfo/jdev Unsubscribe: [email protected] _______________________________________________
