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), keyrings(7), keyutils(7)