pam_keyinit

PAM_KEYINIT(8)                 Linux-PAM Manual                 PAM_KEYINIT(8)

NAME
       pam_keyinit - Kernel session keyring initialiser module

SYNOPSIS
       pam_keyinit.so [debug] [force] [revoke]

DESCRIPTION
       The pam_keyinit PAM module ensures that the invoking process has a
       session keyring other than the user default session keyring.

       The module checks to see if the process's session keyring is the user-
       session-keyring(7), and, if it is, creates a new session-keyring(7)
       with which to replace it. If a new session keyring is created, it will
       install a link to the user-keyring(7) in the session keyring so that
       keys common to the user will be automatically accessible through it.
       The session keyring of the invoking process will thenceforth be
       inherited by all its children unless they override it.

       In order to allow other PAM modules to attach tokens to the keyring,
       this module provides both an auth (limited to pam_setcred(3) and a
       session component. The session keyring is created in the module called.
       Moreover this module should be included as early as possible in a PAM
       configuration.

       This module is intended primarily for use by login processes. Be aware
       that after the session keyring has been replaced, the old session
       keyring and the keys it contains will no longer be accessible.

       This module should not, generally, be invoked by programs like su,
       since it is usually desirable for the key set to percolate through to
       the alternate context. The keys have their own permissions system to
       manage this.

       The keyutils package is used to manipulate keys more directly. This can
       be obtained from:

       Keyutils[1]

OPTIONS
       debug
           Log debug information with syslog(3).

       force
           Causes the session keyring of the invoking process to be replaced
           unconditionally.

       revoke
           Causes the session keyring of the invoking process to be revoked
           when the invoking process exits if the session keyring was created
           for this process in the first place.

MODULE TYPES PROVIDED
       Only the session module type is provided.

RETURN VALUES
       PAM_SUCCESS
           This module will usually return this value

       PAM_AUTH_ERR
           Authentication failure.

       PAM_BUF_ERR
           Memory buffer error.

       PAM_IGNORE
           The return value should be ignored by PAM dispatch.

       PAM_SERVICE_ERR
           Cannot determine the user name.

       PAM_SESSION_ERR
           This module will return this value if its arguments are invalid or
           if a system error such as ENOMEM occurs.

       PAM_USER_UNKNOWN
           User not known.

EXAMPLES
       Add this line to your login entries to start each login session with
       its own session keyring:

           session  required  pam_keyinit.so

       This will prevent keys from one session leaking into another session
       for the same user.

SEE ALSO
       pam.conf(5), pam.d(5), pam(7), keyctl(1)

AUTHOR
       pam_keyinit was written by David Howells, <dhowells@redhat.com>.

NOTES
        1. Keyutils
           http://people.redhat.com/~dhowells/keyutils/

Linux-PAM Manual                  06/08/2020                    PAM_KEYINIT(8)