bind9/bin/dnssec/dnssec-keygen.rst

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..
   Copyright (C) Internet Systems Consortium, Inc. ("ISC")

   This Source Code Form is subject to the terms of the Mozilla Public
   License, v. 2.0. If a copy of the MPL was not distributed with this
   file, You can obtain one at http://mozilla.org/MPL/2.0/.

   See the COPYRIGHT file distributed with this work for additional
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.. highlight: console

.. _man_dnssec-keygen:

dnssec-keygen: DNSSEC key generation tool
-----------------------------------------

Synopsis
~~~~~~~~

:program:`dnssec-keygen` [**-3**] [**-A** date/offset] [**-a** algorithm] [**-b** keysize] [**-C**] [**-c** class] [**-D** date/offset] [**-d** bits] [**-D** sync date/offset] [**-E** engine] [**-f** flag] [**-G**] [**-g** generator] [**-h**] [**-I** date/offset] [**-i** interval] [**-K** directory] [**-k** policy] [**-L** ttl] [**-l** file] [**-n** nametype] [**-P** date/offset] [**-P** sync date/offset] [**-p** protocol] [**-q**] [**-R** date/offset] [**-S** key] [**-s** strength] [**-T** rrtype] [**-t** type] [**-V**] [**-v** level] {name}

Description
~~~~~~~~~~~

``dnssec-keygen`` generates keys for DNSSEC (Secure DNS), as defined in
:rfc:`2535` and :rfc:`4034`. It can also generate keys for use with TSIG
(Transaction Signatures) as defined in :rfc:`2845`, or TKEY (Transaction
Key) as defined in :rfc:`2930`.

The ``name`` of the key is specified on the command line. For DNSSEC
keys, this must match the name of the zone for which the key is being
generated.

The ``dnssec-keymgr`` command acts as a wrapper
around ``dnssec-keygen``, generating and updating keys
as needed to enforce defined security policies such as key rollover
scheduling. Using ``dnssec-keymgr`` may be preferable
to direct use of ``dnssec-keygen``.

Options
~~~~~~~

**-3**
   Use an NSEC3-capable algorithm to generate a DNSSEC key. If this
   option is used with an algorithm that has both NSEC and NSEC3
   versions, then the NSEC3 version will be used; for example,
   ``dnssec-keygen -3a RSASHA1`` specifies the NSEC3RSASHA1 algorithm.

**-a** algorithm
   Selects the cryptographic algorithm. For DNSSEC keys, the value of
   ``algorithm`` must be one of RSASHA1, NSEC3RSASHA1, RSASHA256,
   RSASHA512, ECDSAP256SHA256, ECDSAP384SHA384, ED25519 or ED448. For
   TKEY, the value must be DH (Diffie Hellman); specifying his value
   will automatically set the ``-T KEY`` option as well.

   These values are case insensitive. In some cases, abbreviations are
   supported, such as ECDSA256 for ECDSAP256SHA256 and ECDSA384 for
   ECDSAP384SHA384. If RSASHA1 is specified along with the ``-3``
   option, then NSEC3RSASHA1 will be used instead.

   This parameter *must* be specified except when using the ``-S``
   option, which copies the algorithm from the predecessor key.

   In prior releases, HMAC algorithms could be generated for use as TSIG
   keys, but that feature has been removed as of BIND 9.13.0. Use
   ``tsig-keygen`` to generate TSIG keys.

**-b** keysize
   Specifies the number of bits in the key. The choice of key size
   depends on the algorithm used. RSA keys must be between 1024 and 4096
   bits. Diffie Hellman keys must be between 128 and 4096 bits. Elliptic
   curve algorithms don't need this parameter.

   If the key size is not specified, some algorithms have pre-defined
   defaults. For example, RSA keys for use as DNSSEC zone signing keys
   have a default size of 1024 bits; RSA keys for use as key signing
   keys (KSKs, generated with ``-f KSK``) default to 2048 bits.

**-C**
   Compatibility mode: generates an old-style key, without any timing
   metadata. By default, ``dnssec-keygen`` will include the key's
   creation date in the metadata stored with the private key, and other
   dates may be set there as well (publication date, activation date,
   etc). Keys that include this data may be incompatible with older
   versions of BIND; the ``-C`` option suppresses them.

**-c** class
   Indicates that the DNS record containing the key should have the
   specified class. If not specified, class IN is used.

**-d** bits
   Key size in bits. For the algorithms RSASHA1, NSEC3RSASA1, RSASHA256 and
   RSASHA512 the key size must be in range 1024-4096.  DH size is between 128
   and 4096. This option is ignored for algorithms ECDSAP256SHA256,
   ECDSAP384SHA384, ED25519 and ED448.

**-E** engine
   Specifies the cryptographic hardware to use, when applicable.

   When BIND is built with OpenSSL PKCS#11 support, this defaults to the
   string "pkcs11", which identifies an OpenSSL engine that can drive a
   cryptographic accelerator or hardware service module. When BIND is
   built with native PKCS#11 cryptography (--enable-native-pkcs11), it
   defaults to the path of the PKCS#11 provider library specified via
   "--with-pkcs11".

**-f** flag
   Set the specified flag in the flag field of the KEY/DNSKEY record.
   The only recognized flags are KSK (Key Signing Key) and REVOKE.

**-G**
   Generate a key, but do not publish it or sign with it. This option is
   incompatible with -P and -A.

**-g** generator
   If generating a Diffie Hellman key, use this generator. Allowed
   values are 2 and 5. If no generator is specified, a known prime from
   :rfc:`2539` will be used if possible; otherwise the default is 2.

**-h**
   Prints a short summary of the options and arguments to
   ``dnssec-keygen``.

**-K** directory
   Sets the directory in which the key files are to be written.

**-k** policy
   Create keys for a specific dnssec-policy.  If a policy uses multiple keys,
   ``dnssec-keygen`` will generate multiple keys.  This will also
   create a ".state" file to keep track of the key state.

   This option creates keys according to the dnssec-policy configuration, hence
   it cannot be used together with many of the other options that
   ``dnssec-keygen`` provides.

**-L** ttl
   Sets the default TTL to use for this key when it is converted into a
   DNSKEY RR. If the key is imported into a zone, this is the TTL that
   will be used for it, unless there was already a DNSKEY RRset in
   place, in which case the existing TTL would take precedence. If this
   value is not set and there is no existing DNSKEY RRset, the TTL will
   default to the SOA TTL. Setting the default TTL to ``0`` or ``none``
   is the same as leaving it unset.

**-l** file
   Provide a configuration file that contains a dnssec-policy statement
   (matching the policy set with ``-k``).

**-n** nametype
   Specifies the owner type of the key. The value of ``nametype`` must
   either be ZONE (for a DNSSEC zone key (KEY/DNSKEY)), HOST or ENTITY
   (for a key associated with a host (KEY)), USER (for a key associated
   with a user(KEY)) or OTHER (DNSKEY). These values are case
   insensitive. Defaults to ZONE for DNSKEY generation.

**-p** protocol
   Sets the protocol value for the generated key, for use with
   ``-T KEY``. The protocol is a number between 0 and 255. The default
   is 3 (DNSSEC). Other possible values for this argument are listed in
   :rfc:`2535` and its successors.

**-q**
   Quiet mode: Suppresses unnecessary output, including progress
   indication. Without this option, when ``dnssec-keygen`` is run
   interactively to generate an RSA or DSA key pair, it will print a
   string of symbols to ``stderr`` indicating the progress of the key
   generation. A '.' indicates that a random number has been found which
   passed an initial sieve test; '+' means a number has passed a single
   round of the Miller-Rabin primality test; a space means that the
   number has passed all the tests and is a satisfactory key.

**-S** key
   Create a new key which is an explicit successor to an existing key.
   The name, algorithm, size, and type of the key will be set to match
   the existing key. The activation date of the new key will be set to
   the inactivation date of the existing one. The publication date will
   be set to the activation date minus the prepublication interval,
   which defaults to 30 days.

**-s** strength
   Specifies the strength value of the key. The strength is a number
   between 0 and 15, and currently has no defined purpose in DNSSEC.

**-T** rrtype
   Specifies the resource record type to use for the key. ``rrtype``
   must be either DNSKEY or KEY. The default is DNSKEY when using a
   DNSSEC algorithm, but it can be overridden to KEY for use with
   SIG(0).

**-t** type
   Indicates the use of the key, for use with ``-T  KEY``. ``type``
   must be one of AUTHCONF, NOAUTHCONF, NOAUTH, or NOCONF. The default
   is AUTHCONF. AUTH refers to the ability to authenticate data, and
   CONF the ability to encrypt data.

**-V**
   Prints version information.

**-v** level
   Sets the debugging level.

Timing Options
~~~~~~~~~~~~~~

Dates can be expressed in the format YYYYMMDD or YYYYMMDDHHMMSS. If the
argument begins with a '+' or '-', it is interpreted as an offset from
the present time. For convenience, if such an offset is followed by one
of the suffixes 'y', 'mo', 'w', 'd', 'h', or 'mi', then the offset is
computed in years (defined as 365 24-hour days, ignoring leap years),
months (defined as 30 24-hour days), weeks, days, hours, or minutes,
respectively. Without a suffix, the offset is computed in seconds. To
explicitly prevent a date from being set, use 'none' or 'never'.

**-P** date/offset
   Sets the date on which a key is to be published to the zone. After
   that date, the key will be included in the zone but will not be used
   to sign it. If not set, and if the -G option has not been used, the
   default is "now".

**-P** sync date/offset
   Sets the date on which CDS and CDNSKEY records that match this key
   are to be published to the zone.

**-A** date/offset
   Sets the date on which the key is to be activated. After that date,
   the key will be included in the zone and used to sign it. If not set,
   and if the -G option has not been used, the default is "now". If set,
   if and -P is not set, then the publication date will be set to the
   activation date minus the prepublication interval.

**-R** date/offset
   Sets the date on which the key is to be revoked. After that date, the
   key will be flagged as revoked. It will be included in the zone and
   will be used to sign it.

**-I** date/offset
   Sets the date on which the key is to be retired. After that date, the
   key will still be included in the zone, but it will not be used to
   sign it.

**-D** date/offset
   Sets the date on which the key is to be deleted. After that date, the
   key will no longer be included in the zone. (It may remain in the key
   repository, however.)

**-D** sync date/offset
   Sets the date on which the CDS and CDNSKEY records that match this
   key are to be deleted.

**-i** interval
   Sets the prepublication interval for a key. If set, then the
   publication and activation dates must be separated by at least this
   much time. If the activation date is specified but the publication
   date isn't, then the publication date will default to this much time
   before the activation date; conversely, if the publication date is
   specified but activation date isn't, then activation will be set to
   this much time after publication.

   If the key is being created as an explicit successor to another key,
   then the default prepublication interval is 30 days; otherwise it is
   zero.

   As with date offsets, if the argument is followed by one of the
   suffixes 'y', 'mo', 'w', 'd', 'h', or 'mi', then the interval is
   measured in years, months, weeks, days, hours, or minutes,
   respectively. Without a suffix, the interval is measured in seconds.

Generated Keys
~~~~~~~~~~~~~~

When ``dnssec-keygen`` completes successfully, it prints a string of the
form ``Knnnn.+aaa+iiiii`` to the standard output. This is an
identification string for the key it has generated.

-  ``nnnn`` is the key name.

-  ``aaa`` is the numeric representation of the algorithm.

-  ``iiiii`` is the key identifier (or footprint).

``dnssec-keygen`` creates two files, with names based on the printed
string. ``Knnnn.+aaa+iiiii.key`` contains the public key, and
``Knnnn.+aaa+iiiii.private`` contains the private key.

The ``.key`` file contains a DNSKEY or KEY record. When a zone is being
signed by ``named`` or ``dnssec-signzone`` ``-S``, DNSKEY records are
included automatically. In other cases, the ``.key`` file can be
inserted into a zone file manually or with a ``$INCLUDE`` statement.

The ``.private`` file contains algorithm-specific fields. For obvious
security reasons, this file does not have general read permission.

Example
~~~~~~~

To generate an ECDSAP256SHA256 zone-signing key for the zone
``example.com``, issue the command:

``dnssec-keygen -a ECDSAP256SHA256 example.com``

The command would print a string of the form:

``Kexample.com.+013+26160``

In this example, ``dnssec-keygen`` creates the files
``Kexample.com.+013+26160.key`` and ``Kexample.com.+013+26160.private``.

To generate a matching key-signing key, issue the command:

``dnssec-keygen -a ECDSAP256SHA256 -f KSK example.com``

See Also
~~~~~~~~

:manpage:`dnssec-signzone(8)`, BIND 9 Administrator Reference Manual, :rfc:`2539`,
:rfc:`2845`, :rfc:`4034`.