Regarding PAM_TTY_KLUDGE and Solaris 8...

Nicolas Williams Nicolas.Williams at
Fri Oct 26 05:50:29 EST 2001

On Thu, Oct 25, 2001 at 03:30:38PM -0400, Nicolas Williams wrote:
> On Thu, Oct 25, 2001 at 10:51:01AM -0700, Darren Moffat wrote:
> > It is up to the calling application and its' conversation function to
> > deal with getting the information from the user.  If pam_acct_mgmt
> > returns PAM_NEW_AUTHTOK_REQD and sshd isn't able to prompt the user for
> > one (because it has no tty) then it has to make its own choice of what
> > to do, it can continue and ignore it or it can display a warning or it
> > can disconnect - it is upto sshd to choose what to do (it could use
> > SSH_ASKPASS if it is available).
> if pam_acct_mgmt() returns PAM_NEW_AUTHTOK_REQD and the application
> can't call pam_chauthtok() or do the subsequent prompting of the user
> then the app should NOT just go on.

That aside, it would be nice to have two standard PAM conversation
functions, one for conversing on a TTY, the other for conversing via
something like SSH_ASKPASS (or PAM_ASK_ITEM :)

> In the case of Kerberos password validation doing so would open the
> application to a major KDC spoofing attack. This is because there is
> nothing in the AS-REP to prove to the application that the response came
> from a valid KDC -- the host can only validate the KDC by getting a TGT
> and then a service ticket for a host principal for which that host has a
> valid key stored locally.
> > --
> > Darren J Moffat


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