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keyctl(2)


NAME

   keyctl - manipulate the kernel's key management facility

SYNOPSIS

   #include <keyutils.h>

   long keyctl(int cmd, ...);

DESCRIPTION

   keyctl() has a number of functions available:

   KEYCTL_GET_KEYRING_ID
          Ask for a keyring's ID.

   KEYCTL_JOIN_SESSION_KEYRING
          Join or start named session keyring.

   KEYCTL_UPDATE
          Update a key.

   KEYCTL_REVOKE
          Revoke a key.

   KEYCTL_CHOWN
          Set ownership of a key.

   KEYCTL_SETPERM
          Set perms on a key.

   KEYCTL_DESCRIBE
          Describe a key.

   KEYCTL_CLEAR
          Clear contents of a keyring.

   KEYCTL_LINK
          Link a key into a keyring.

   KEYCTL_UNLINK
          Unlink a key from a keyring.

   KEYCTL_SEARCH
          Search for a key in a keyring.

   KEYCTL_READ
          Read a key or keyring's contents.

   KEYCTL_INSTANTIATE
          Instantiate a partially constructed key.

   KEYCTL_NEGATE
          Negate a partially constructed key.

   KEYCTL_SET_REQKEY_KEYRING
          Set default request-key keyring.

   KEYCTL_SET_TIMEOUT
          Set timeout on a key.

   KEYCTL_ASSUME_AUTHORITY
          Assume authority to instantiate key.

   These  are  wrapped  by  libkeyutils  into individual functions (listed
   under SEE ALSO) to permit the compiler to check types.

RETURN VALUE

   On success keyctl() 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

   EACCES A key operation wasn't permitted.

   EDQUOT The key quota  for  the  caller's  user  would  be  exceeded  by
          creating a key or linking it to the keyring.

   EKEYEXPIRED
          An expired key was found or specified.

   EKEYREJECTED
          A rejected key was found or specified.

   EKEYREVOKED
          A revoked key was found or specified.

   ENOKEY No matching key was found or an invalid key was specified.

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), request_key(2), keyctl_chown(3),
   keyctl_clear(3), keyctl_describe(3), keyctl_describe_alloc(3),
   keyctl_get_keyring_ID(3), keyctl_instantiate(3),
   keyctl_join_session_keyring(3), keyctl_link(3), keyctl_negate(3),
   keyctl_read(3), keyctl_read_alloc(3), keyctl_revoke(3),
   keyctl_search(3), keyctl_set_reqkey_keyring(3), keyctl_set_timeout(3),
   keyctl_setperm(3), keyctl_unlink(3), keyctl_update(3), keyrings(7),
   request-key(8)

   The kernel source file Documentation/security/keys.txt.

COLOPHON

   This page is part of release 4.09 of the Linux man-pages project.  A
   description of the project, information about reporting bugs, and the
   latest version of this page, can be found at
   https://www.kernel.org/doc/man-pages/.



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