брелок для каждого пользователя (per-user keyring)
Имя (Name)
user-keyring - per-user keyring
Описание (Description)
The user keyring is a keyring used to anchor keys on behalf of a
user. Each UID the kernel deals with has its own user keyring
that is shared by all processes with that UID. The user keyring
has a name (description) of the form _uid.<UID> where <UID> is
the user ID of the corresponding user.
The user keyring is associated with the record that the kernel
maintains for the UID. It comes into existence upon the first
attempt to access either the user keyring, the
user-session-keyring(7), or the session-keyring(7). The keyring
remains pinned in existence so long as there are processes
running with that real UID or files opened by those processes
remain open. (The keyring can also be pinned indefinitely by
linking it into another keyring.)
Typically, the user keyring is created by pam_keyinit(8) when a
user logs in.
The user keyring is not searched by default by request_key(2).
When pam_keyinit(8) creates a session keyring, it adds to it a
link to the user keyring so that the user keyring will be
searched when the session keyring is.
A special serial number value, KEY_SPEC_USER_KEYRING, is defined
that can be used in lieu of the actual serial number of the
calling process's user keyring.
From the keyctl(1) utility, '@u' can be used instead of a numeric
key ID in much the same way.
User keyrings are independent of clone(2), fork(2), vfork(2),
execve(2), and _exit(2) excepting that the keyring is destroyed
when the UID record is destroyed when the last process pinning it
exits.
If it is necessary for a key associated with a user to exist
beyond the UID record being garbage collected—for example, for
use by a cron(8) script—then the persistent-keyring(7) should be
used instead.
If a user keyring does not exist when it is accessed, it will be
created.
Смотри также (See also)
keyctl(1), keyctl(3), keyrings(7), persistent-keyring(7),
process-keyring(7), session-keyring(7), thread-keyring(7),
user-session-keyring(7), pam_keyinit(8)
