I don't think you can do that with a plugin without core Dovecot modifications. Unless you replace the whole passdb ldap. For example you could use passdb checkpassword if performance isn't a big issue.
On 9.10.2012, at 22.24, James Devine wrote: > Here is an example of the problem: > > Oct 9 13:19:53 smtp-outgoing2 dovecot: auth: Debug: > password(u...@domain.tld,192.168.160.49): Generating NTLM from user > 'u...@domain.tld@', password 'IfBG6G3jykirE5r5vienC4w==' > Oct 9 13:19:53 smtp-outgoing2 dovecot: auth: Debug: > password(u...@domain.tld,192.168.160.49): Credentials: > f124dc24328ed3d90db035f0d5284636 > > The listed password is a base64 representation of its encrypted form which > I need to somehow decrypt between the time LDAP returns it and these > credentials are generated. > > > > On Tue, Oct 9, 2012 at 1:16 PM, James Devine <fxmul...@gmail.com> wrote: > >> I don't think I understand. Right now the problem is the password >> retrieved from LDAP cannot be hashed to compare against what the user sent >> because it is encrypted. I have to perform my AES decryption before it can >> be hashed and compared. >> >> >> On Tue, Oct 9, 2012 at 1:03 PM, btb <b...@bitrate.net> wrote: >> >>> On 2012.10.09 14.41, James Devine wrote: >>> >>>> We have an LDAP server that contains AES encrypted passwords. So far >>>> I've >>>> been able to use this by adding a passdb module that encrypts the user's >>>> password prior to ldap comparison. Now I am looking at supporting >>>> client-side encrypted passwords. To do this I need to decrypt the >>>> password >>>> returned by LDAP. Is there a way to insert a module to do this >>>> decryption >>>> between ldap returning and the auth mechanism? >>>> >>>> that would be unwise, generally speaking. as a rule of thumb, in terms >>> of security fundamentals, only the rootdn [or equiv] should be able to read >>> the values in an ldap entry's password attribute. certainly the service >>> account used by dovecot should not. >>> >>> in the context of ldap, authentication should be accomplished by binding >>> as the user, not by retrieving attribute values and performing string >>> comparisons. among other things, this decouples the two components and >>> allows applications [e.g. dovecot] to be unconcerned with whatever password >>> hashing scheme the directory server might be using. >>> >>> -ben >>> >> >>