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add_key(2) [centos man page]

ADD_KEY(2)						    Linux Key Management Calls							ADD_KEY(2)

NAME
add_key - add a key to the kernel's key management facility SYNOPSIS
#include <keyutils.h> key_serial_t add_key(const char *type, const char *description, const void *payload, size_t plen, key_serial_t keyring); DESCRIPTION
add_key() asks the kernel to create or update a key of the given type and description, instantiate it with the payload of length plen, and to attach it to the nominated keyring and to return its serial number. The key type may reject the data if it's in the wrong format or in some other way invalid. If the destination keyring already contains a key that matches the specified type and description then, if the key type supports it, that key will be updated rather than a new key being created; if not, a new key will be created and it will displace the link to the extant key from the keyring. The destination keyring serial number may be that of a valid keyring to which the caller has write permission, or it may be a special keyring ID: KEY_SPEC_THREAD_KEYRING This specifies the caller's thread-specific keyring. KEY_SPEC_PROCESS_KEYRING This specifies the caller's process-specific keyring. KEY_SPEC_SESSION_KEYRING This specifies the caller's session-specific keyring. KEY_SPEC_USER_KEYRING This specifies the caller's UID-specific keyring. KEY_SPEC_USER_SESSION_KEYRING This specifies the caller's UID-session keyring. KEY TYPES
There are a number of key types available in the core key management code, and these can be specified to this function: "user" Keys of the user-defined key type may contain a blob of arbitrary data, and the description may be any valid string, though it is preferred that the description be prefixed with a string representing the service to which the key is of interest and a colon (for instance "afs:mykey"). The payload may be empty or NULL for keys of this type. "keyring" Keyrings are special key types that may contain links to sequences of other keys of any type. If this interface is used to create a keyring, then a NULL payload should be specified, and plen should be zero. RETURN VALUE
On success add_key() returns the serial number of the key it created or updated. On error, the value -1 will be returned and errno will have been set to an appropriate error. ERRORS
ENOKEY The keyring doesn't exist. EKEYEXPIRED The keyring has expired. EKEYREVOKED The keyring has been revoked. EINVAL The payload data was invalid. ENOMEM Insufficient memory to create a key. EDQUOT The key quota for this user would be exceeded by creating this key or linking it to the keyring. EACCES The keyring wasn't available for modification by the user. 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), keyctl(2), request_key(2) 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 ADD_KEY(2)

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KEYCTL_GET_KEYRING_ID(3)				    Linux Key Management Calls					  KEYCTL_GET_KEYRING_ID(3)

NAME
keyctl_get_keyring_ID - Get the ID of a special keyring SYNOPSIS
#include <keyutils.h> key_serial_t keyctl_get_keyring_ID(key_serial_t key, int create); DESCRIPTION
keyctl_get_keyring_ID() maps a special key or keyring ID to the serial number of the key actually representing that feature. The serial number will be returned if that key exists. If the key or keyring does not yet exist, then if create is non-zero, the key or keyring will be created if it is appropriate to do so. The following special key IDs may be specified as key: KEY_SPEC_THREAD_KEYRING This specifies the caller's thread-specific keyring. KEY_SPEC_PROCESS_KEYRING This specifies the caller's process-specific keyring. KEY_SPEC_SESSION_KEYRING This specifies the caller's session-specific keyring. KEY_SPEC_USER_KEYRING This specifies the caller's UID-specific keyring. KEY_SPEC_USER_SESSION_KEYRING This specifies the caller's UID-session keyring. KEY_SPEC_REQKEY_AUTH_KEY This specifies the authorisation key created by request_key() and passed to the process it spawns to generate a key. If a valid keyring ID is passed in, then this will simply be returned if the key exists; an error will be issued if it doesn't exist. RETURN VALUE
On success keyctl_get_keyring_ID() 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
ENOKEY No matching key was found. ENOMEM Insufficient memory to create a key. EDQUOT The key quota for this user would be exceeded by creating this key or linking it to the keyring. 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_join_session_keyring(3), keyctl_update(3), keyctl_revoke(3), keyctl_chown(3), keyctl_setperm(3), keyctl_describe(3), keyctl_clear(3), keyctl_link(3), keyctl_unlink(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_GET_KEYRING_ID(3)

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