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keyctl(2) [centos man page]

KEYCTL(2)						    Linux Key Management Calls							 KEYCTL(2)

NAME
keyctl - manipulate the kernel's key management facility SYNOPSIS
#include <keyutils.h> long keyctl(int cmd, ...); DESCRIPTION
keyctl() has a number of functions available: KEYCTL_GET_KEYRING_ID Ask for a keyring's ID. KEYCTL_JOIN_SESSION_KEYRING Join or start named session keyring. KEYCTL_UPDATE Update a key. KEYCTL_REVOKE Revoke a key. KEYCTL_CHOWN Set ownership of a key. KEYCTL_SETPERM Set perms on a key. KEYCTL_DESCRIBE Describe a key. KEYCTL_CLEAR Clear contents of a keyring. KEYCTL_LINK Link a key into a keyring. KEYCTL_UNLINK Unlink a key from a keyring. KEYCTL_SEARCH Search for a key in a keyring. KEYCTL_READ Read a key or keyring's contents. KEYCTL_INSTANTIATE Instantiate a partially constructed key. KEYCTL_NEGATE Negate a partially constructed key. KEYCTL_SET_REQKEY_KEYRING Set default request-key keyring. KEYCTL_SET_TIMEOUT Set timeout on a key. KEYCTL_ASSUME_AUTHORITY Assume authority to instantiate key. These are wrapped by libkeyutils into individual functions to permit compiler the compiler to check types. See the See Also section at the bottom. RETURN VALUE
On success keyctl() returns the serial number of the key it found. On error, the value -1 will be returned and errno will have been set to an appropriate error. ERRORS
EACCES A key operation wasn't permitted. EDQUOT The key quota for the caller's user would be exceeded by creating a key or linking it to the keyring. EKEYEXPIRED An expired key was found or specified. EKEYREJECTED A rejected key was found or specified. EKEYREVOKED A revoked key was found or specified. ENOKEY No matching key was found or an invalid key was specified. LINKING
Although this is a Linux system call, it is not present in libc but can be found rather in libkeyutils. When linking, -lkeyutils should be specified to the linker. SEE ALSO
keyctl(1), add_key(2), request_key(2), keyctl_set_timeout(3), keyctl_chown(3), keyctl_clear(3), keyctl_describe(3), keyctl_describe_alloc(3), keyctl_get_keyring_ID(3), keyctl_instantiate(3), keyctl_join_session_keyring(3), keyctl_link(3), keyctl_negate(3), keyctl_revoke(3), keyctl_search(3), keyctl_setperm(3), keyctl_set_reqkey_keyring(3), keyctl_set_timeout(3), keyctl_read(3), keyctl_read_alloc(3), keyctl_unlink(3), keyctl_update(3), request-key(8) COLOPHON
This page is part of release 3.53 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/. Linux 2010-02-25 KEYCTL(2)

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KEYCTL_LINK(3)						    Linux Key Management Calls						    KEYCTL_LINK(3)

NAME
keyctl_link - Link a key to a keyring keyctl_unlink - Unlink a key from a keyring SYNOPSIS
#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); DESCRIPTION
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 create or remove links in it. The caller must have link permission on a key to be able to create a link to it. RETURN VALUE
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 appro- priate error. ERRORS
ENOKEY The key or the keyring specified are invalid. EKEYEXPIRED The key or the keyring specified have expired. EKEYREVOKED The key or the keyring specified have been revoked. EACCES The keyring exists, but is not writable by the calling process. For keyctl_link() only: ENOMEM Insufficient memory to expand the keyring EDQUOT Expanding the keyring would exceed the keyring owner's quota. EACCES The key exists, but is not linkable by the calling process. LINKING
This is a library function that can be found in libkeyutils. When linking, -lkeyutils should be specified to the linker. SEE ALSO
keyctl(1), add_key(2), keyctl(2), request_key(2), keyctl_get_keyring_ID(3), keyctl_join_session_keyring(3), keyctl_update(3), keyctl_revoke(3), keyctl_chown(3), keyctl_setperm(3), keyctl_describe(3), keyctl_clear(3), keyctl_search(3), keyctl_read(3), keyctl_instantiate(3), keyctl_negate(3), keyctl_set_reqkey_keyring(3), keyctl_set_timeout(3), keyctl_assume_authority(3), keyctl_describe_alloc(3), keyctl_read_alloc(3), request-key(8) Linux 4 May 2006 KEYCTL_LINK(3)

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