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add_key(2) [suse 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 EKEYREVOKED The keyring has been revoked.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 3.25 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_SEARCH(3)					    Linux Key Management Calls						  KEYCTL_SEARCH(3)

NAME
keyctl_search - Search a keyring for a key SYNOPSIS
#include <keyutils.h> long keyctl_search(key_serial_t keyring, const char *type, const char *description, key_serial_t destination); DESCRIPTION
keyctl_search() recursively searches the keyring for a key of the specified type and description. If found, the key will be attached to the destination keyring (if given), and its serial number will be returned. The source keyring must grant search permission to the caller, and for a key to be found, it must also grant search permission to the call- er. Child keyrings will be only be recursively searched if they grant search permission to the caller as well. If the destination keyring is zero, no attempt will be made to forge a link to the key, and just the serial number will be returned. If the destination keyring is given, then the link may only be formed if the found key grants the caller link permission and the destina- tion keyring grants the caller write permission. If the search is successful, and if the destination keyring already contains a link to a key that matches the specified type and descrip- tion, then that link will be replaced by a link to the found key. The source keyring and destination keyring serial numbers may be those of valid keyrings to which the caller has appropriate permission, or they may be special keyring IDs: 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. RETURN VALUE
On success keyctl_search() 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 One of the keyrings doesn't exist, no key was found by the search, or the only key found by the search was a negative key. ENOTDIR One of the keyrings is a valid key that isn't a keyring. EKEYEXPIRED One of the keyrings has expired, or the only key found was expired. EKEYREVOKED One of the keyrings has been revoked, or the only key found was revoked. ENOMEM Insufficient memory to expand the destination keyring. EDQUOT The key quota for this user would be exceeded by creating a link to the found key in the destination keyring. EACCES The source keyring didn't grant search permission, the destination keyring didn't grant write permission or the found key didn't grant link permission to the caller. 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), keyctl(2), request_key(2), keyctl(3), request-key(8) Linux 4 May 2006 KEYCTL_SEARCH(3)

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