find_key_by_type_and_name - find a key by type and name
key_serial_t find_key_by_type_and_name(const char *type,
const char *description, key_serial_t destringid);
find_key_by_type_and_name() searches for a key with the given type
and exact description, firstly in the thread, process and session
keyrings to which a process is subscribed and secondly in /proc/keys.
If a key is found, and destringid is not 0 and specifies a
keyring, then the found key will be linked into it.
The function returns the ID of the key if a key was found or -1 otherwise.
When linking, -lkeyutils should be specified to the linker.
- No key was found or the keyring specified is invalid.
- The key or keyring have expired.
- The key or keyring have been revoked.
- The key is not accessible or keyring exists, but is not writable by
the calling process.