NAME

       user-session-keyring - Per-user default session keyring

DESCRIPTION

       The user session keyring is a keyring used to anchor keys on behalf of a user.  Each UID the kernel deals
       with  has  its  own  user  session  keyring.   This keyring is associated with the record that the kernel
       maintains for the UID and, once created, is retained as long as  that  record  persists.   It  is  shared
       amongst all processes of that UID.

       The  user  session  keyring  is created on demand when a thread requests it or when a thread asks for its
       session keyring and that doesn't exist.  In the latter case, a user session keyring will be created  and,
       if the session keyring wasn't to be created, the user session keyring will be set as the process's actual
       session keyring.

       The user session keyring is searched by request_key() if the actual session keyring does not exist and is
       ignored otherwise.

       A  special serial number value, KEY_SPEC_USER_SESSION_KEYRING, is defined that can be used in lieu of the
       calling process's user session keyring's actual serial number.

       From the keyctl utility, '@us' can be used instead of a numeric key ID in much the same way.

       User session keyrings are independent of clone(), fork(), vfork(), execve() and exit() excepting that the
       keyring is destroyed when the UID record is destroyed when the last process pinning it exits.

       If a user session keyring does not exist when it is accessed, it will be created.

       It is strongly recommended that a session keyring be set explicitly, for example by  pam_keyinit,  rather
       than relying on the user session keyring - particularly if a process is running as root.

SEE ALSO

       keyctl(1),
       keyctl(3),
       keyrings(7),
       process-keyring(7),
       session-keyring(7),
       thread-keyring(7),
       user-keyring(7),
       persistent-keyring(7)

Linux                                              20 Feb 2014                           USER-SESSION-KEYRING(7)