[Bug 2913] mod_auth_pam fallthrough always fails (because mod_auth_pam never returns PAM_USER_UNKNOWN)

[Christian Reis]

Public bug report changed:
https://launchpad.net/malone/bugs/2913

Comment:
The reason this fails is because our configuration of PAM makes
mod_auth_pam never return DECLINED. The reason is that
pam_authenticate() seems to never return PAM_USER_UNKNOWN. IIRC it
always returns PAM_AUTH_ERR, and this email seems to confirm it:

http://archives.neohapsis.com/archives/pam-list/2001-03/0060.html

The reply to that email, at

http://archives.neohapsis.com/archives/pam-list/2001-03/0059.html

seems to indicate it's a bug in the pam configuration. I'm not so sure
it is, but if it is, it's broken in Debian and Ubuntu because I never
changed anything in /etc/pam.d/.