DOKK / manpages / debian 12 / libkeyutils-dev / keyctl_link.3.en
KEYCTL_LINK(3) Linux Key Management Calls KEYCTL_LINK(3)

keyctl_link, keyctl_unlink - link/unlink a key to/from a keyring

#include <keyutils.h>

long keyctl_link(key_serial_t key, key_serial_t keyring);

long keyctl_unlink(key_serial_t key, key_serial_t keyring);

keyctl_link() creates a link from keyring to key, displacing any link to another key of the same type and description in that keyring if one exists.

keyctl_unlink() removes the link from keyring to key if it exists.

The caller must have write permission on a keyring to be able to create or remove links in it.

The caller must have link permission on a key to be able to create a link to it.

On success keyctl_link() and keyctl_unlink() return 0. On error, the value -1 will be returned and errno will have been set to an appropriate error.

The key or the keyring specified are invalid.
The key or the keyring specified have expired.
The key or the keyring specified have been revoked.
The keyring exists, but is not writable by the calling process.

For keyctl_link() only:

Insufficient memory to expand the keyring
Expanding the keyring would exceed the keyring owner's quota.
The key exists, but is not linkable by the calling process.

This is a library function that can be found in libkeyutils. When linking, -lkeyutils should be specified to the linker.

keyctl(1), add_key(2), keyctl(2), request_key(2), keyctl(3), keyrings(7), keyutils(7)

4 May 2006 Linux