dnssec-keygen - DNSSEC key generation tool
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}
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.
- -3
- This option uses 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 is selected; for example,
dnssec-keygen -3 -a RSASHA1 specifies the NSEC3RSASHA1
algorithm.
- -a algorithm
- This option 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 this value automatically
sets 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, NSEC3RSASHA1 is 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 was removed in BIND 9.13.0. Use
tsig-keygen to generate TSIG keys.
- -b keysize
- This option 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 do not 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
- This option enables compatibility mode, which generates an old-style key,
without any timing metadata. By default, dnssec-keygen includes the
key's creation date in the metadata stored with the private key; other
dates may be set there as well, including 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
- This option indicates that the DNS record containing the key should have
the specified class. If not specified, class IN is used.
- -d bits
- This option specifies the key size in bits. For the algorithms RSASHA1,
NSEC3RSASA1, RSASHA256, and RSASHA512 the key size must be between 1024
and 4096 bits; DH size is between 128 and 4096 bits. This option is
ignored for algorithms ECDSAP256SHA256, ECDSAP384SHA384, ED25519, and
ED448.
- -E engine
- This option specifies the cryptographic hardware to use, when applicable.
When BIND 9 is built with OpenSSL, this needs to be set to the
OpenSSL engine identifier that drives the cryptographic accelerator or
hardware service module (usually pkcs11). 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
- This option sets the specified flag in the flag field of the KEY/DNSKEY
record. The only recognized flags are KSK (Key-Signing Key) and
REVOKE.
- -G
- This option generates a key, but does not publish it or sign with it. This
option is incompatible with -P and -A.
- -g generator
- This option indicates the generator to use if generating a Diffie-Hellman
key. Allowed values are 2 and 5. If no generator is specified, a known
prime from RFC 2539 is used if possible; otherwise the default is
2.
- -h
- This option prints a short summary of the options and arguments to
dnssec-keygen.
- -K directory
- This option sets the directory in which the key files are to be
written.
- -k policy
- This option creates keys for a specific dnssec-policy. If a policy
uses multiple keys, dnssec-keygen generates multiple keys. This
also creates 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 at the same time as many of the
other options that dnssec-keygen provides.
- -L ttl
- This option sets the default TTL to use for this key when it is converted
into a DNSKEY RR. This is the TTL used when the key is imported into a
zone, unless there was already a DNSKEY RRset in place, in which case the
existing TTL takes precedence. If this value is not set and there is no
existing DNSKEY RRset, the TTL defaults to the SOA TTL. Setting the
default TTL to 0 or none is the same as leaving it
unset.
- -l file
- This option provides a configuration file that contains a
dnssec-policy statement (matching the policy set with
-k).
- -n nametype
- This option 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. The default is ZONE for DNSKEY generation.
- -p protocol
- This option 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
- This option sets quiet mode, which suppresses unnecessary output,
including progress indication. Without this option, when
dnssec-keygen is run interactively to generate an RSA or DSA key
pair, it prints 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; and a space
( ) means that the number has passed all the tests and is a satisfactory
key.
- -S key
- This option creates a new key which is an explicit successor to an
existing key. The name, algorithm, size, and type of the key are set to
match the existing key. The activation date of the new key is set to the
inactivation date of the existing one. The publication date is set to the
activation date minus the prepublication interval, which defaults to 30
days.
- -s strength
- This option 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
- This option 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
- This option indicates the type 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 to the ability to encrypt data.
- -V
- This option prints version information.
- -v level
- This option sets the debugging level.
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
- This option sets the date on which a key is to be published to the zone.
After that date, the key is included in the zone but is not used to sign
it. If not set, and if the -G option has not been used, the default
is the current date.
- -P sync
date/offset
- This option sets the date on which CDS and CDNSKEY records that match this
key are to be published to the zone.
- -A
date/offset
- This option sets the date on which the key is to be activated. After that
date, the key is included in the zone and used to sign it. If not set, and
if the -G option has not been used, the default is the current
date. If set, and -P is not set, the publication date is set to the
activation date minus the prepublication interval.
- -R
date/offset
- This option sets the date on which the key is to be revoked. After that
date, the key is flagged as revoked. It is included in the zone and is
used to sign it.
- -I
date/offset
- This option sets the date on which the key is to be retired. After that
date, the key is still included in the zone, but it is not used to sign
it.
- -D
date/offset
- This option sets the date on which the key is to be deleted. After that
date, the key is no longer included in the zone. (However, it may remain
in the key repository.)
- -D sync
date/offset
- This option sets the date on which the CDS and CDNSKEY records that match
this key are to be deleted.
- -i interval
- This option 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 is not,
the publication date defaults to this much time before the activation
date; conversely, if the publication date is specified but not the
activation date, activation is 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, the interval is measured in years, months, weeks, days,
hours, or minutes, respectively. Without a suffix, the interval is
measured in seconds.
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 an $INCLUDE statement.
The .private file contains algorithm-specific fields. For
obvious security reasons, this file does not have general read
permission.
To generate an ECDSAP256SHA256 zone-signing key for the zone
example.com, issue the command:
dnssec-keygen -a ECDSAP256SHA256 example.com
The command prints 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
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