Provided by: keyutils_1.6-6_amd64 bug

NAME

       keyctl - key management facility control

SYNOPSIS

       keyctl --version
       keyctl show [-x] [<keyring>]
       keyctl add <type> <desc> <data> <keyring>
       keyctl padd <type> <desc> <keyring>
       keyctl request <type> <desc> [<dest_keyring>]
       keyctl request2 <type> <desc> <info> [<dest_keyring>]
       keyctl prequest2 <type> <desc> [<dest_keyring>]
       keyctl update <key> <data>
       keyctl pupdate <key>
       keyctl newring <name> <keyring>
       keyctl revoke <key>
       keyctl clear <keyring>
       keyctl link <key> <keyring>
       keyctl unlink <key> [<keyring>]
       keyctl search <keyring> <type> <desc> [<dest_keyring>]
       keyctl restrict_keyring <keyring> [<type> [<restriction>]]
       keyctl read <key>
       keyctl pipe <key>
       keyctl print <key>
       keyctl list <keyring>
       keyctl rlist <keyring>
       keyctl describe <keyring>
       keyctl rdescribe <keyring> [sep]
       keyctl chown <key> <uid>
       keyctl chgrp <key> <gid>
       keyctl setperm <key> <mask>
       keyctl new_session
       keyctl session
       keyctl session - [<prog> <arg1> <arg2> ...]
       keyctl session <name> [<prog> <arg1> <arg2> ...]
       keyctl instantiate <key> <data> <keyring>
       keyctl pinstantiate <key> <keyring>
       keyctl negate <key> <timeout> <keyring>
       keyctl reject <key> <timeout> <error> <keyring>
       keyctl timeout <key> <timeout>
       keyctl security <key>
       keyctl reap [-v]
       keyctl purge <type>
       keyctl purge [-i] [-p] <type> <desc>
       keyctl purge -s <type> <desc>
       keyctl get_persistent <keyring> [<uid>]
       keyctl dh_compute <private> <prime> <base>
       keyctl dh_compute_kdf <private> <prime> <base> <output_length> <hash_type>
       keyctl dh_compute_kdf_oi <private> <prime> <base> <output_length> <hash_type>
       keyctl pkey_query <key> <pass> [k=v]*
       keyctl pkey_encrypt <key> <pass> <datafile> [k=v]* ><encfile>
       keyctl pkey_decrypt <key> <pass> <encfile> [k=v]* ><datafile>
       keyctl pkey_sign <key> <pass> <datafile> [k=v]* ><sigfile>
       keyctl pkey_decrypt <key> <pass> <datafile> <sigfile> [k=v]*

DESCRIPTION

       This  program  is  used  to  control  the  key management facility in various ways using a
       variety of subcommands.

KEY IDENTIFIERS

       The key identifiers passed to or returned from keyctl are, in general, positive  integers.
       There  are,  however,  some  special  values  with  special meanings that can be passed as
       arguments:

       No key: 0

       Thread keyring: @t or -1
              Each thread may have its own keyring. This is searched first,  before  all  others.
              The thread keyring is replaced by (v)fork, exec and clone.

       Process keyring: @p or -2
              Each  process  (thread  group) may have its own keyring. This is shared between all
              members of a group and will be searched  after  the  thread  keyring.  The  process
              keyring is replaced by (v)fork and exec.

       Session keyring: @s or -3
              Each process subscribes to a session keyring that is inherited across (v)fork, exec
              and clone. This is searched after the process  keyring.  Session  keyrings  can  be
              named  and  an extant keyring can be joined in place of a process's current session
              keyring.

       User specific keyring: @u or -4
              This keyring is shared between all the processes owned by  a  particular  user.  It
              isn't searched directly, but is normally linked to from the session keyring.

       User default session keyring: @us or -5
              This  is  the  default  session keyring for a particular user. Login processes that
              change to a particular user will bind to this session until another session is set.

       Group specific keyring: @g or -6
              This is a  place  holder  for  a  group  specific  keyring,  but  is  not  actually
              implemented yet in the kernel.

       Assumed request_key authorisation key: @a or -7
              This  selects  the authorisation key provided to the request_key() helper to permit
              it to access the callers keyrings and instantiate the target key.

       Keyring by name: %:<name>
              A named keyring.  This will be searched  for  in  the  process's  keyrings  and  in
              /proc/keys.

       Key by name: %<type>:<name>
              A named key of the given type.  This will be searched for in the process's keyrings
              and in /proc/keys.

COMMAND SYNTAX

       Any non-ambiguous shortening of a command name may be used in lieu  of  the  full  command
       name. This facility should not be used in scripting as new commands may be added in future
       that then cause ambiguity.

   Display the package version number
       keyctl --version

       This command prints the package version number and build date and exits:

              $ keyctl --version
              keyctl from keyutils-1.5.3 (Built 2011-08-24)

   Show process keyrings
       keyctl show [-x] [<keyring>]

       By default this command recursively shows what keyrings a process  is  subscribed  to  and
       what  keys and keyrings they contain.  If a keyring is specified then that keyring will be
       dumped instead.  If -x is specified then the keyring IDs will be dumped in hex instead  of
       decimal.

   Add a key to a keyring
       keyctl add <type> <desc> <data> <keyring>
       keyctl padd <type> <desc> <keyring>

       This command creates a key of the specified type and description; instantiates it with the
       given data and attaches it to the specified keyring. It then prints the new  key's  ID  on
       stdout:

              $ keyctl add user mykey stuff @u
              26

       The  padd  variant of the command reads the data from stdin rather than taking it from the
       command line:

              $ echo -n stuff | keyctl padd user mykey @u 26

   Request a key
       keyctl request <type> <desc> [<dest_keyring>]
       keyctl request2 <type> <desc> <info> [<dest_keyring>]
       keyctl prequest2 <type> <desc> [<dest_keyring>]

       These three commands request the lookup of a key of the given type  and  description.  The
       process's keyrings will be searched, and if a match is found the matching key's ID will be
       printed to stdout; and if a destination keyring is given, the key will be  added  to  that
       keyring also.

       If  there  is  no key, the first command will simply return the error ENOKEY and fail. The
       second and third commands will create a partial key with the  type  and  description,  and
       call  out to /sbin/request-key with that key and the extra information supplied. This will
       then attempt to instantiate the key in some manner, such that a valid key is obtained.

       The third command is like the second, except that the callout  information  is  read  from
       stdin rather than being passed on the command line.

       If a valid key is obtained, the ID will be printed and the key attached as if the original
       search had succeeded.

       If there wasn't a valid key obtained, a temporary negative key will  be  attached  to  the
       destination keyring if given and the error "Requested key not available" will be given.

              $ keyctl request2 user debug:hello wibble
              23
              $ echo -n wibble | keyctl prequest2 user debug:hello
              23
              $ keyctl request user debug:hello
              23

   Update a key
       keyctl update <key> <data>
       keyctl pupdate <key>

       This  command  replaces  the data attached to a key with a new set of data. If the type of
       the key doesn't support update then error "Operation not supported" will be returned.

              $ keyctl update 23 zebra

       The pupdate variant of the command reads the data from stdin rather than  taking  it  from
       the command line:

              $ echo -n zebra | keyctl pupdate 23

   Create a keyring
       keyctl newring <name> <keyring>

       This  command creates a new keyring of the specified name and attaches it to the specified
       keyring. The ID of the new keyring will be printed to stdout if successful.

              $ keyctl newring squelch @us
              27

   Revoke a key
       keyctl revoke <key>

       This command marks a key as being revoked. Any further operations on that key (apart  from
       unlinking it) will return error "Key has been revoked".

              $ keyctl revoke 26
              $ keyctl describe 26
              keyctl_describe: Key has been revoked

   Clear a keyring
       keyctl clear <keyring>

       This  command  unlinks  all  the  keys  attached  to  the  specified keyring. Error "Not a
       directory" will be returned if the key specified is not a keyring.

              $ keyctl clear 27

   Link a key to a keyring
       keyctl link <key> <keyring>

       This command makes a link from the key to the keyring if there's enough capacity to do so.
       Error  "Not  a  directory"  will  be  returned  if the destination is not a keyring. Error
       "Permission denied" will be returned if the  key  doesn't  have  link  permission  or  the
       keyring doesn't have write permission. Error "File table overflow" will be returned if the
       keyring is full. Error "Resource deadlock avoided" will be returned if an attempt was made
       to introduce a recursive link.

              $ keyctl link 23 27
              $ keyctl link 27 27
              keyctl_link: Resource deadlock avoided

   Unlink a key from a keyring or the session keyring tree
       keyctl unlink <key> [<keyring>]

       If  the  keyring  is  specified,  this command removes a link to the key from the keyring.
       Error "Not a directory" will be returned if  the  destination  is  not  a  keyring.  Error
       "Permission  denied"  will be returned if the keyring doesn't have write permission. Error
       "No such file or directory" will be returned if the key is not linked to by the keyring.

       If the keyring is not specified, this command performs a depth-first search of the session
       keyring  tree and removes all the links to the nominated key that it finds (and that it is
       permitted to remove).  It prints the number of successful unlinks before exiting.

              $ keyctl unlink 23 27

   Search a keyring
       keyctl search <keyring> <type> <desc> [<dest_keyring>]

       This command non-recursively searches a keyring  for  a  key  of  a  particular  type  and
       description.  If  found,  the  ID of the key will be printed on stdout and the key will be
       attached to the destination keyring if present. Error "Requested key not  available"  will
       be returned if the key is not found.

              $ keyctl search @us user debug:hello
              23
              $ keyctl search @us user debug:bye
              keyctl_search: Requested key not available

   Restrict a keyring
       keyctl restrict_keyring <keyring> [<type> [<restriction>]]

       This  command limits the linkage of keys to the given keyring using a provided restriction
       scheme. The scheme is associated with a given key type, with further details  provided  in
       the  restriction  option  string.   Options  typically contain a restriction name possibly
       followed by key ids or other data relevant to the restriction. If no restriction scheme is
       provided, the keyring will reject all links.

              $ keyctl restrict_keyring $1 asymmetric builtin_trusted

   Read a key
       keyctl read <key>
       keyctl pipe <key>
       keyctl print <key>

       These commands read the payload of a key. "read" prints it on stdout as a hex dump, "pipe"
       dumps the raw data to stdout and "print" dumps it to  stdout  directly  if  it's  entirely
       printable or as a hexdump preceded by ":hex:" if not.

       If  the  key  type  does  not  support  reading  of the payload, then error "Operation not
       supported" will be returned.

              $ keyctl read 26
              1 bytes of data in key:
              62
              $ keyctl print 26
              b
              $ keyctl pipe 26
              $

   List a keyring
       keyctl list <keyring>
       keyctl rlist <keyring>

       These commands list the contents of a key as a keyring. "list" pretty prints the  contents
       and "rlist" just produces a space-separated list of key IDs.

       No attempt is made to check that the specified keyring is a keyring.

              $ keyctl list @us
              2 keys in keyring:
                     22: vrwsl----------  4043    -1 keyring: _uid.4043
                     23: vrwsl----------  4043  4043 user: debug:hello
              $ keyctl rlist @us
              22 23

   Describe a key
       keyctl describe <keyring>
       keyctl rdescribe <keyring> [sep]

       These  commands fetch a description of a keyring. "describe" pretty prints the description
       in the same fashion as the "list" command; "rdescribe" prints the raw data  returned  from
       the kernel.

              $ keyctl describe @us
                     -5: vrwsl----------  4043    -1 keyring: _uid_ses.4043
              $ keyctl rdescribe @us
              keyring;4043;-1;3f1f0000;_uid_ses.4043

       The  raw  string  is "<type>;<uid>;<gid>;<perms>;<description>", where uid and gid are the
       decimal user and group IDs, perms is the permissions mask in hex, type and description are
       the type name and description strings (neither of which will contain semicolons).

   Change the access controls on a key
       keyctl chown <key> <uid>
       keyctl chgrp <key> <gid>

       These  two  commands change the UID and GID associated with evaluating a key's permissions
       mask. The UID also governs which quota a key is taken out of.

       The chown command is not currently supported; attempting it will earn the error "Operation
       not supported" at best.

       For  non-superuser  users,  the  GID  may only be set to the process's GID or a GID in the
       process's groups list. The superuser may set any GID it likes.

              $ sudo keyctl chown 27 0
              keyctl_chown: Operation not supported
              $ sudo keyctl chgrp 27 0

   Set the permissions mask on a key
       keyctl setperm <key> <mask>

       This command changes the permission control mask on a key. The mask may be specified as  a
       hex  number  if  it  begins  "0x",  an  octal  number if it begins "0" or a decimal number
       otherwise.

       The hex numbers are a combination of:

              Possessor UID       GID       Other     Permission Granted
              ========  ========  ========  ========  ==================
              01000000  00010000  00000100  00000001  View
              02000000  00020000  00000200  00000002  Read
              04000000  00040000  00000400  00000004  Write
              08000000  00080000  00000800  00000008  Search
              10000000  00100000  00001000  00000010  Link
              20000000  00200000  00002000  00000020  Set Attribute
              3f000000  003f0000  00003f00  0000003f  All

       View permits the type, description and other parameters of a key to be viewed.

       Read permits the payload (or keyring list) to be read if supported by the type.

       Write permits the payload (or keyring list) to be modified or updated.

       Search on a key permits it to be found when a keyring to which it is linked is searched.

       Link permits a key to be linked to a keyring.

       Set Attribute permits a key to have its owner,  group  membership,  permissions  mask  and
       timeout changed.

              $ keyctl setperm 27 0x1f1f1f00

   Start a new session with fresh keyrings
       keyctl session
       keyctl session - [<prog> <arg1> <arg2> ...]
       keyctl session <name> [<prog> <arg1> <arg2> ...]

       These  commands  join  or  create a new keyring and then run a shell or other program with
       that keyring as the session key.

       The variation with no arguments just creates an anonymous  session  keyring  and  attaches
       that as the session keyring; it then exec's $SHELL.

       The  variation  with  a  dash  in place of a name creates an anonymous session keyring and
       attaches that as the session keyring; it then exec's the supplied command,  or  $SHELL  if
       one isn't supplied.

       The variation with a name supplied creates or joins the named keyring and attaches that as
       the session keyring; it then exec's the supplied command, or $SHELL if one isn't supplied.

              $ keyctl rdescribe @s
              keyring;4043;-1;3f1f0000;_uid_ses.4043

              $ keyctl session
              Joined session keyring: 28

              $ keyctl rdescribe @s
              keyring;4043;4043;3f1f0000;_ses.24082

              $ keyctl session -
              Joined session keyring: 29
              $ keyctl rdescribe @s
              keyring;4043;4043;3f1f0000;_ses.24139

              $ keyctl session - keyctl rdescribe @s
              Joined session keyring: 30
              keyring;4043;4043;3f1f0000;_ses.24185

              $ keyctl session fish
              Joined session keyring: 34
              $ keyctl rdescribe @s
              keyring;4043;4043;3f1f0000;fish

              $ keyctl session fish keyctl rdesc @s
              Joined session keyring: 35
              keyring;4043;4043;3f1f0000;fish

   Instantiate a key
       keyctl instantiate <key> <data> <keyring>
       keyctl pinstantiate <key> <keyring>
       keyctl negate <key> <timeout> <keyring>
       keyctl reject <key> <timeout> <error> <keyring>

       These commands are used to attach data to a partially set up key (as created by the kernel
       and  passed  to /sbin/request-key).  "instantiate" marks a key as being valid and attaches
       the data as the payload.  "negate" and "reject" mark a key as invalid and sets  a  timeout
       on  it  so  that  it'll  go away after a while.  This prevents a lot of quickly sequential
       requests from slowing the system down overmuch when  they  all  fail,  as  all  subsequent
       requests will then fail with error "Requested key not found" (if negated) or the specified
       error (if rejected) until the negative key has expired.

       Reject's error argument can either be a UNIX error number or one of 'rejected',  'expired'
       or 'revoked'.

       The newly instantiated key will be attached to the specified keyring.

       These  commands  may  only  be  run  from  the  program  run  by  request-key  - a special
       authorisation key is set up by the  kernel  and  attached  to  the  request-key's  session
       keyring. This special key is revoked once the key to which it refers has been instantiated
       one way or another.

              $ keyctl instantiate $1 "Debug $3" $4
              $ keyctl negate $1 30 $4
              $ keyctl reject $1 30 64 $4

       The pinstantiate variant of the command reads the data from stdin rather  than  taking  it
       from the command line:

              $ echo -n "Debug $3" | keyctl pinstantiate $1 $4

   Set the expiry time on a key
       keyctl timeout <key> <timeout>

       This  command  is  used  to  set the timeout on a key, or clear an existing timeout if the
       value specified is zero. The timeout is given as a number of seconds into the future.

              $ keyctl timeout $1 45

   Retrieve a key's security context
       keyctl security <key>

       This command is used to retrieve a key's LSM security context.  The label  is  printed  on
       stdout.

              $ keyctl security @s
              unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023

   Give the parent process a new session keyring
       keyctl new_session

       This  command  is  used  to  give  the  invoking process (typically a shell) a new session
       keyring, discarding its old session keyring.

              $  keyctl session foo
              Joined session keyring: 723488146
              $  keyctl show
              Session Keyring
                     -3 --alswrv      0     0  keyring: foo
              $  keyctl new_session
              490511412
              $  keyctl show
              Session Keyring
                     -3 --alswrv      0     0  keyring: _ses

       Note that this affects the parent of the process that invokes the system call, and so  may
       only  affect  processes  with matching credentials.  Furthermore, the change does not take
       effect till the parent process  next  transitions  from  kernel  space  to  user  space  -
       typically when the wait() system call returns.

   Remove dead keys from the session keyring tree
       keyctl reap

       This  command  performs  a  depth-first  search  of  the caller's session keyring tree and
       attempts to unlink any key that it finds that is inaccessible due to  expiry,  revocation,
       rejection  or  negation.   It  does  not  attempt to remove live keys that are unavailable
       simply due to a lack of granted permission.

       A key that is designated reapable will only be removed from a keyring if  the  caller  has
       Write  permission  on  that keyring, and only keyrings that grant Search permission to the
       caller will be searched.

       The command prints the number of keys reaped before it exits.  If the -v  flag  is  passed
       then  the  reaped  keys  are  listed as they're being reaped, together with the success or
       failure of the unlink.

   Remove matching keys from the session keyring tree
       keyctl purge <type>
       keyctl purge [-i] [-p] <type> <desc>
       keyctl purge -s <type> <desc>

       These commands perform a depth-first search to find matching keys in the caller's  session
       keyring  tree  and  attempts  to unlink them.  The number of keys successfully unlinked is
       printed at the end.

       The keyrings must grant Read and View permission to the caller to  be  searched,  and  the
       keys  to  be  removed  must  also  grant  View  permission.  Keys can only be removed from
       keyrings that grant Write permission.

       The first variant purges all keys of the specified type.

       The second variant purges all keys of  the  specified  type  that  also  match  the  given
       description literally.  The -i flag allows a case-independent match and the -p flag allows
       a prefix match.

       The third variant purges all keys of the specified type and matching description using the
       key  type's  comparator in the kernel to match the description.  This permits the key type
       to match a key with a variety of descriptions.

   Get persistent keyring
       keyctl get_persistent <keyring> [<uid>]

       This command gets the persistent keyring for either the current UID or the  specified  UID
       and  attaches it to the nominated keyring.  The persistent keyring's ID will be printed on
       stdout.

       The kernel will create the keyring if it doesn't exist and  every  time  this  command  is
       called, will reset the expiration timeout on the keyring to the value in:

              /proc/sys/kernel/keys/persistent_keyring_expiry

       (by  default  three  days).  Should the timeout be reached, the persistent keyring will be
       removed and everything it pins can then be garbage collected.

       If a UID other than the process's real or effective UIDs is specified, then an error  will
       be given if the process does not have the CAP_SETUID capability.

   Compute a Diffie-Hellman shared secret or public key
       keyctl dh_compute <private> <prime> <base>

       This   command   computes  either  a  Diffie-Hellman  shared  secret  or  the  public  key
       corresponding to  the  provided  private  key  using  the  payloads  of  three  keys.  The
       computation is:

              base ^ private (mod prime)

       The three inputs must be user keys with read permission. If the provided base key contains
       the shared generator value, the public key will be computed.  If  the  provided  base  key
       contains the remote public key value, the shared secret will be computed.

       The result is printed to stdout as a hex dump.

              $ keyctl dh_compute $1 $2 $3
              8 bytes of data in result:
              00010203 04050607

   Compute a Diffie-Hellman shared secret and derive key material
       keyctl dh_compute_kdf <private> <prime> <base> <output_length> <hash_type>

       This  command  computes  a  Diffie-Hellman shared secret and derives key material from the
       shared secret using a key derivation function (KDF).  The  shared  secret  is  derived  as
       outlined  above  and is input to the KDF using the specified hash type. The hash type must
       point to a hash name known to the kernel crypto API.

       The operation derives key material of the length specified by the caller.

       The operation is compliant to the specification of SP800-56A.

       The result is printed to stdout as hex dump.

   Compute a Diffie-Hellman shared secret and apply KDF with other input
       keyctl dh_compute_kdf_oi <private> <prime> <base> <output_length> <hash_type>

       This command is identical to the  command  dh_compute_kdf  to  generate  a  Diffie-Hellman
       shared  secret  followed  by a key derivation operation. This command allows the caller to
       provide the other input data (OI data) compliant to SP800-56A via stdin.

   Perform public-key operations with an asymmetric key
       keyctl pkey_query <key> <pass> [k=v]*
       keyctl pkey_encrypt <key> <pass> <datafile> [k=v]* > <encfile>
       keyctl pkey_decrypt <key> <pass> <encfile> [k=v]* > <datafile>
       keyctl pkey_sign <key> <pass> <datafile> [k=v]* > <sigfile>
       keyctl pkey_verify <key> <pass> <datafile> <sigfile> [k=v]*

       These commands query an asymmetric key, encrypt data with it, decrypt the encrypted  data,
       generate  a  signature over some data and verify that signature.  For encrypt, decrypt and
       sign, the resulting data is written to stdout; verify reads the  data  and  the  signature
       files and compares them.

       [!] NOTE that the data is of very limited capacity, with no more bits than the size of the
       key.  For signatures, the caller is expected to digest the actual data  and  pass  in  the
       result  of  the digest as the datafile.  The name of the digest should be specified on the
       end of the command line as "hash=<name>".

       The key ID indicates the key to use; pass is a placeholder for future  password  provision
       and should be "0" for the moment; datafile is the unencrypted data to be encrypted, signed
       or to have its signature checked; encfile is a file containing encrypted data; and sigfile
       is a file containing a signature.

       A  list  of parameters in "key[=val]" form can be included on the end of the command line.
       These specify things like the digest algorithm used ("hash=<name>") or the  encoding  form
       ("enc=<type>").

              k=`keyctl padd asymmetric "" @s <key.pkcs8.der`
              keyctl pkey_query $k 0 enc=pkcs1 hash=sha256
              keyctl pkey_encrypt $k 0 foo.hash enc=pkcs1 >foo.enc
              keyctl pkey_decrypt $k 0 foo.enc enc=pkcs1 >foo.hash
              keyctl pkey_sign $k 0 foo.hash enc=pkcs1 hash=sha256 >foo.sig
              keyctl pkey_verify $k 0 foo.hash foo.sig enc=pkcs1 hash=sha256

       See asymmetric-key(7) for more information.

ERRORS

       There are a number of common errors returned by this program:

       "Not a directory" - a key wasn't a keyring.

       "Requested key not found" - the looked for key isn't available.

       "Key has been revoked" - a revoked key was accessed.

       "Key has expired" - an expired key was accessed.

       "Permission denied" - permission was denied by a UID/GID/mask combination.

SEE ALSO

       keyctl(1), keyctl(2), request_key(2), keyctl(3), request-key.conf(5), keyrings(7),
       request-key(8)