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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  caller.
       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  destination
       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
       description,  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)