NAME

       keyctl_update - update a key

SYNOPSIS

       #include <keyutils.h>

       long keyctl_update(key_serial_t key, const void *payload,
       size_t plen);

DESCRIPTION

       keyctl_update() updates the payload of a key if the key type permits it.

       The caller must have write permission on a key to be able to update it.

       payload  and  plen specify the data for the new payload.  payload may be NULL and plen may
       be zero if the key type permits that.  The key type may reject the data  if  it's  in  the
       wrong format or in some other way invalid.

RETURN VALUE

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

ERRORS

       ENOKEY The key specified is invalid.

       EKEYEXPIRED
              The key specified has expired.

       EKEYREVOKED
              The key specified had been revoked.

       EINVAL The payload data was invalid.

       ENOMEM Insufficient memory to store the new payload.

       EDQUOT The key quota for this user would be exceeded by increasing the size of the key  to
              accommodate the new payload.

       EACCES The key exists, but is not writable by the calling process.

       EOPNOTSUPP
              The key type does not support the update operation on its keys.

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(3), keyrings(7), keyutils(7)