pam_winbind — PAM module for Winbind
This tool is part of the samba(7) suite.
pam_winbind is a PAM module that can authenticate users against the local domain by talking to the Winbind daemon.
Edit the PAM system config /etc/pam.d/service and modify it as the following example shows:
... auth required pam_env.so auth sufficient pam_unix2.so +++ auth required pam_winbind.so use_first_pass account requisite pam_unix2.so +++ account required pam_winbind.so use_first_pass +++ password sufficient pam_winbind.so password requisite pam_pwcheck.so cracklib password required pam_unix2.so use_authtok session required pam_unix2.so +++ session required pam_winbind.so ...
Make sure that pam_winbind is one of the first modules in the session part. It may retrieve kerberos tickets which are needed by other modules.
pam_winbind supports several options which can either be set in
the PAM configuration files or in the pam_winbind configuration
file situated at
from the PAM configuration file take precedence to those from
the configuration file. See
for further details.
Gives debugging output to syslog.
Gives detailed PAM state debugging output to syslog.
If this option is set, pam_winbind will only succeed if the user is a member of the given SID or NAME. A SID
can be either a group-SID, an alias-SID or even an user-SID. It is also possible to give a NAME instead of the
SID. That name must have the form:
MYDOMAIN\myuser (where '\' character corresponds to the value of
winbind separator parameter). It is also possible to use a UPN in the form
group@REALM. pam_winbind will, in that case, lookup
the SID internally. Note that NAME may not contain any spaces. It is thus recommended to only use SIDs. You can
verify the list of SIDs a user is a member of with
This option must only be specified on a auth module declaration, as it only operates in conjunction with password authentication.
By default, pam_winbind tries to get the authentication token from a previous module. If no token is available it asks the user for the old password. With this option, pam_winbind aborts with an error if no authentication token from a previous module is available.
Same as the use_first_pass option (previous item), except that if the primary password is not valid, PAM will prompt for a password.
Set the new password to the one provided by the previously stacked password module. If this option is not set pam_winbind will ask the user for the new password.
Same as the use_authtok option (previous item), except that if the new password is not valid, PAM will prompt for a password.
pam_winbind can authenticate using Kerberos when winbindd is
talking to an Active Directory domain controller. Kerberos
authentication must be enabled with this parameter. When
Kerberos authentication can not succeed (e.g. due to clock
skew), winbindd will fallback to samlogon authentication over
MSRPC. When this parameter is used in conjunction with
winbind refresh tickets, winbind will
keep your Ticket Granting Ticket (TGT) up-to-date by refreshing
it whenever necessary.
When pam_winbind is configured to try kerberos authentication
by enabling the
krb5_auth option, it can
store the retrieved Ticket Granting Ticket (TGT) in a
credential cache. The type of credential cache can be
controlled with this option. The supported values are:
(when supported by the system's Kerberos library and
(when the DIR type is supported by the system's Kerberos
library). In case of FILE a credential cache in the form of
/tmp/krb5cc_UID will be created - in case of DIR you NEED
to specify a directory which must exist, the UID directory
will be created in the specified directory.
In all cases UID is replaced with the numeric user id.
Check the details of the Kerberos implementation.
When using the KEYRING type, the supported mechanism is “KEYRING:persistent:UID”, which uses the Linux kernel keyring to store credentials on a per-UID basis. KEYRING has limitations. For example, it is secure kernel memory, so bulk storage of credentials is not possible.
When using the KCM type, the supported mechanism is “KCM:UID”, which uses a Kerberos credential manager to store credentials on a per-UID basis similar to KEYRING. This is the recommended choice on latest Linux distributions that offer a Kerberos Credential Manager. If not, we suggest to use KEYRING, as those are the most secure and predictable method.
It is also possible to define custom filepaths and use the "%u" pattern in order to substitute the numeric user id. Examples:
This will create a credential cache file in the specified directory.
This will create a credential cache file.
Leave empty to just do kerberos authentication without having a ticket cache after the logon has succeeded. This setting is empty by default.
Winbind allows one to logon using cached credentials when
winbind offline logon is enabled. To use this feature from the PAM module this option must be set.
Do not emit any messages.
Create homedirectory for a user on-the-fly, option is valid in PAM session block.
Defines number of days before pam_winbind starts to warn about passwords that are going to expire. Defaults to 14 days.
This section describes the data exported in the PAM stack which could be used in other PAM modules.
This is the Windows Home Directory set in the profile tab in the user settings on the Active Directory Server. This could be a local path or a directory on a share mapped to a drive.
The path to the logon script which should be executed if a user logs in. This is normally a relative path to the script stored on the server.
This exports the Active Directory server we are authenticating against. This can be used as a variable later.
This is the profile path set in the profile tab in the user settings. Normally the home directory is synced with this directory on a share.