NAME
ntp-keygen —
Create a NTP host
key
SYNOPSIS
ntp-keygen |
[-flags]
[-flag
[value]]
[--option-name[[=|
]value]]
All arguments must be options. |
DESCRIPTION
This program generates cryptographic data files used by the NTPv4 authentication
and identification schemes. It generates MD5 key files used in symmetric key
cryptography. In addition, if the OpenSSL software library has been installed,
it generates keys, certificate and identity files used in public key
cryptography. These files are used for cookie encryption, digital signature
and challenge/response identification algorithms compatible with the Internet
standard security infrastructure.
All files are in PEM-encoded printable ASCII format, so they can be embedded as
MIME attachments in mail to other sites and certificate authorities. By
default, files are not encrypted.
When used to generate message digest keys, the program produces a file
containing ten pseudo-random printable ASCII strings suitable for the MD5
message digest algorithm included in the distribution. If the OpenSSL library
is installed, it produces an additional ten hex-encoded random bit strings
suitable for the SHA1 and other message digest algorithms. The message digest
keys file must be distributed and stored using secure means beyond the scope
of NTP itself. Besides the keys used for ordinary NTP associations, additional
keys can be defined as passwords for the
ntpq(8) and
ntpdc(8) utility programs.
The remaining generated files are compatible with other OpenSSL applications and
other Public Key Infrastructure (PKI) resources. Certificates generated by
this program are compatible with extant industry practice, although some users
might find the interpretation of X509v3 extension fields somewhat liberal.
However, the identity keys are probably not compatible with anything other
than Autokey.
Some files used by this program are encrypted using a private password. The
-p option specifies the password for local encrypted files
and the
-q option the password for encrypted files sent to
remote sites. If no password is specified, the host name returned by the Unix
gethostname() function, normally the DNS name of the host is
used.
The
pw option of the
crypto
configuration command specifies the read password for previously encrypted
local files. This must match the local password used by this program. If not
specified, the host name is used. Thus, if files are generated by this program
without password, they can be read back by
ntpd without
password but only on the same host.
Normally, encrypted files for each host are generated by that host and used only
by that host, although exceptions exist as noted later on this page. The
symmetric keys file, normally called
ntp.keys, is
usually installed in
/etc. Other files and links are usually
installed in
/usr/local/etc, which is normally in a shared
filesystem in NFS-mounted networks and cannot be changed by shared clients.
The location of the keys directory can be changed by the
keysdir configuration command in such cases. Normally,
this is in
/etc.
This program directs commentary and error messages to the standard error stream
stderr and remote files to the standard output stream
stdout where they can be piped to other applications or
redirected to files. The names used for generated files and links all begin
with the string
ntpkey and include the file type,
generating host and filestamp, as described in the “Cryptographic Data
Files” section below.
Running the Program
To test and gain experience with Autokey concepts, log in as root and change to
the keys directory, usually
/usr/local/etc When run for the
first time, or if all files with names beginning with
ntpkey have been removed, use the
ntp-keygen command without arguments to generate a default
RSA host key and matching RSA-MD5 certificate with expiration date one year
hence. If run again without options, the program uses the existing keys and
parameters and generates only a new certificate with new expiration date one
year hence.
Run the command on as many hosts as necessary. Designate one of them as the
trusted host (TH) using
ntp-keygen with the
-T option and configure it to synchronize from reliable
Internet servers. Then configure the other hosts to synchronize to the TH
directly or indirectly. A certificate trail is created when Autokey asks the
immediately ascendant host towards the TH to sign its certificate, which is
then provided to the immediately descendant host on request. All group hosts
should have acyclic certificate trails ending on the TH.
The host key is used to encrypt the cookie when required and so must be RSA
type. By default, the host key is also the sign key used to encrypt
signatures. A different sign key can be assigned using the
-S option and this can be either RSA or DSA type. By
default, the signature message digest type is MD5, but any combination of sign
key type and message digest type supported by the OpenSSL library can be
specified using the
-c option. The rules say cryptographic
media should be generated with proventic filestamps, which means the host
should already be synchronized before this program is run. This of course
creates a chicken-and-egg problem when the host is started for the first time.
Accordingly, the host time should be set by some other means, such as
eyeball-and-wristwatch, at least so that the certificate lifetime is within
the current year. After that and when the host is synchronized to a proventic
source, the certificate should be re-generated.
Additional information on trusted groups and identity schemes is on the
“Autokey Public-Key Authentication” page.
The
ntpd(8) configuration command
crypto pw password specifies the read
password for previously encrypted files. The daemon expires on the spot if the
password is missing or incorrect. For convenience, if a file has been
previously encrypted, the default read password is the name of the host
running the program. If the previous write password is specified as the host
name, these files can be read by that host with no explicit password.
File names begin with the prefix
ntpkey_ and end with the
postfix
_hostname.filestamp, where
hostname is the owner name, usually the string returned
by the Unix gethostname() routine, and
filestamp is the
NTP seconds when the file was generated, in decimal digits. This both
guarantees uniqueness and simplifies maintenance procedures, since all files
can be quickly removed by a
rm ntpkey* command or all files
generated at a specific time can be removed by a
rm
*filestamp command. To further reduce the risk of
misconfiguration, the first two lines of a file contain the file name and
generation date and time as comments.
All files are installed by default in the keys directory
/usr/local/etc, which is normally in a shared filesystem in
NFS-mounted networks. The actual location of the keys directory and each file
can be overridden by configuration commands, but this is not recommended.
Normally, the files for each host are generated by that host and used only by
that host, although exceptions exist as noted later on this page.
Normally, files containing private values, including the host key, sign key and
identification parameters, are permitted root read/write-only; while others
containing public values are permitted world readable. Alternatively, files
containing private values can be encrypted and these files permitted world
readable, which simplifies maintenance in shared file systems. Since
uniqueness is insured by the hostname and file name extensions, the files for
a NFS server and dependent clients can all be installed in the same shared
directory.
The recommended practice is to keep the file name extensions when installing a
file and to install a soft link from the generic names specified elsewhere on
this page to the generated files. This allows new file generations to be
activated simply by changing the link. If a link is present, ntpd follows it
to the file name to extract the filestamp. If a link is not present,
ntpd(8) extracts the filestamp
from the file itself. This allows clients to verify that the file and
generation times are always current. The
ntp-keygen program
uses the same timestamp extension for all files generated at one time, so each
generation is distinct and can be readily recognized in monitoring data.
Running the program
The safest way to run the
ntp-keygen program is logged in
directly as root. The recommended procedure is change to the keys directory,
usually
/usr/local/etc, then run the program. When run for
the first time, or if all
ntpkey files have been removed,
the program generates a RSA host key file and matching RSA-MD5 certificate
file, which is all that is necessary in many cases. The program also generates
soft links from the generic names to the respective files. If run again, the
program uses the same host key file, but generates a new certificate file and
link.
The host key is used to encrypt the cookie when required and so must be RSA
type. By default, the host key is also the sign key used to encrypt
signatures. When necessary, a different sign key can be specified and this can
be either RSA or DSA type. By default, the message digest type is MD5, but any
combination of sign key type and message digest type supported by the OpenSSL
library can be specified, including those using the MD2, MD5, SHA, SHA1, MDC2
and RIPE160 message digest algorithms. However, the scheme specified in the
certificate must be compatible with the sign key. Certificates using any
digest algorithm are compatible with RSA sign keys; however, only SHA and SHA1
certificates are compatible with DSA sign keys.
Private/public key files and certificates are compatible with other OpenSSL
applications and very likely other libraries as well. Certificates or
certificate requests derived from them should be compatible with extant
industry practice, although some users might find the interpretation of X509v3
extension fields somewhat liberal. However, the identification parameter
files, although encoded as the other files, are probably not compatible with
anything other than Autokey.
Running the program as other than root and using the Unix
su
command to assume root may not work properly, since by default the OpenSSL
library looks for the random seed file
.rnd in the user home
directory. However, there should be only one
.rnd, most
conveniently in the root directory, so it is convenient to define the
$RANDFILE environment variable used by the OpenSSL library
as the path to
/.rnd.
Installing the keys as root might not work in NFS-mounted shared file systems,
as NFS clients may not be able to write to the shared keys directory, even as
root. In this case, NFS clients can specify the files in another directory
such as
/etc using the
keysdir command.
There is no need for one client to read the keys and certificates of other
clients or servers, as these data are obtained automatically by the Autokey
protocol.
Ordinarily, cryptographic files are generated by the host that uses them, but it
is possible for a trusted agent (TA) to generate these files for other hosts;
however, in such cases files should always be encrypted. The subject name and
trusted name default to the hostname of the host generating the files, but can
be changed by command line options. It is convenient to designate the owner
name and trusted name as the subject and issuer fields, respectively, of the
certificate. The owner name is also used for the host and sign key files,
while the trusted name is used for the identity files.
All files are installed by default in the keys directory
/usr/local/etc, which is normally in a shared filesystem in
NFS-mounted networks. The actual location of the keys directory and each file
can be overridden by configuration commands, but this is not recommended.
Normally, the files for each host are generated by that host and used only by
that host, although exceptions exist as noted later on this page.
Normally, files containing private values, including the host key, sign key and
identification parameters, are permitted root read/write-only; while others
containing public values are permitted world readable. Alternatively, files
containing private values can be encrypted and these files permitted world
readable, which simplifies maintenance in shared file systems. Since
uniqueness is insured by the hostname and file name extensions, the files for
a NFS server and dependent clients can all be installed in the same shared
directory.
The recommended practice is to keep the file name extensions when installing a
file and to install a soft link from the generic names specified elsewhere on
this page to the generated files. This allows new file generations to be
activated simply by changing the link. If a link is present, ntpd follows it
to the file name to extract the filestamp. If a link is not present,
ntpd(8) extracts the filestamp
from the file itself. This allows clients to verify that the file and
generation times are always current. The
ntp-keygen program
uses the same timestamp extension for all files generated at one time, so each
generation is distinct and can be readily recognized in monitoring data.
Running the program
The safest way to run the
ntp-keygen program is logged in
directly as root. The recommended procedure is change to the keys directory,
usually
/usr/local/etc, then run the program. When run for
the first time, or if all
ntpkey files have been removed,
the program generates a RSA host key file and matching RSA-MD5 certificate
file, which is all that is necessary in many cases. The program also generates
soft links from the generic names to the respective files. If run again, the
program uses the same host key file, but generates a new certificate file and
link.
The host key is used to encrypt the cookie when required and so must be RSA
type. By default, the host key is also the sign key used to encrypt
signatures. When necessary, a different sign key can be specified and this can
be either RSA or DSA type. By default, the message digest type is MD5, but any
combination of sign key type and message digest type supported by the OpenSSL
library can be specified, including those using the MD2, MD5, SHA, SHA1, MDC2
and RIPE160 message digest algorithms. However, the scheme specified in the
certificate must be compatible with the sign key. Certificates using any
digest algorithm are compatible with RSA sign keys; however, only SHA and SHA1
certificates are compatible with DSA sign keys.
Private/public key files and certificates are compatible with other OpenSSL
applications and very likely other libraries as well. Certificates or
certificate requests derived from them should be compatible with extant
industry practice, although some users might find the interpretation of X509v3
extension fields somewhat liberal. However, the identification parameter
files, although encoded as the other files, are probably not compatible with
anything other than Autokey.
Running the program as other than root and using the Unix
su
command to assume root may not work properly, since by default the OpenSSL
library looks for the random seed file
.rnd in the user home
directory. However, there should be only one
.rnd, most
conveniently in the root directory, so it is convenient to define the
$RANDFILE environment variable used by the OpenSSL library
as the path to
/.rnd.
Installing the keys as root might not work in NFS-mounted shared file systems,
as NFS clients may not be able to write to the shared keys directory, even as
root. In this case, NFS clients can specify the files in another directory
such as
/etc using the
keysdir command.
There is no need for one client to read the keys and certificates of other
clients or servers, as these data are obtained automatically by the Autokey
protocol.
Ordinarily, cryptographic files are generated by the host that uses them, but it
is possible for a trusted agent (TA) to generate these files for other hosts;
however, in such cases files should always be encrypted. The subject name and
trusted name default to the hostname of the host generating the files, but can
be changed by command line options. It is convenient to designate the owner
name and trusted name as the subject and issuer fields, respectively, of the
certificate. The owner name is also used for the host and sign key files,
while the trusted name is used for the identity files. seconds. seconds. s
Trusted Hosts and Groups Each cryptographic configuration involves selection
of a signature scheme and identification scheme, called a cryptotype, as
explained in the
Authentication
Options section of
ntp.conf(5). The default
cryptotype uses RSA encryption, MD5 message digest and TC identification.
First, configure a NTP subnet including one or more low-stratum trusted hosts
from which all other hosts derive synchronization directly or indirectly.
Trusted hosts have trusted certificates; all other hosts have nontrusted
certificates. These hosts will automatically and dynamically build
authoritative certificate trails to one or more trusted hosts. A trusted group
is the set of all hosts that have, directly or indirectly, a certificate trail
ending at a trusted host. The trail is defined by static configuration file
entries or dynamic means described on the
Automatic NTP
Configuration Options section of
ntp.conf(5).
On each trusted host as root, change to the keys directory. To insure a fresh
fileset, remove all
ntpkey files. Then run
ntp-keygen -T to generate keys and a
trusted certificate. On all other hosts do the same, but leave off the
-T flag to generate keys and nontrusted certificates. When
complete, start the NTP daemons beginning at the lowest stratum and working up
the tree. It may take some time for Autokey to instantiate the certificate
trails throughout the subnet, but setting up the environment is completely
automatic.
If it is necessary to use a different sign key or different digest/signature
scheme than the default, run
ntp-keygen with the
-S type option, where
type is either
RSA or
DSA. The most often need to do this is when a DSA-signed
certificate is used. If it is necessary to use a different certificate scheme
than the default, run
ntp-keygen with the
-c scheme option and selected
scheme as needed. f
ntp-keygen is run
again without these options, it generates a new certificate using the same
scheme and sign key.
After setting up the environment it is advisable to update certificates from
time to time, if only to extend the validity interval. Simply run
ntp-keygen with the same flags as before to generate new
certificates using existing keys. However, if the host or sign key is changed,
ntpd(8) should be restarted. When
ntpd(8) is restarted, it loads any
new files and restarts the protocol. Other dependent hosts will continue as
usual until signatures are refreshed, at which time the protocol is restarted.
Identity Schemes
As mentioned on the Autonomous Authentication page, the default TC identity
scheme is vulnerable to a middleman attack. However, there are more secure
identity schemes available, including PC, IFF, GQ and MV described on the
“Identification Schemes” page (maybe available at
http://www.eecis.udel.edu/%7emills/keygen.html
). These
schemes are based on a TA, one or more trusted hosts and some number of
nontrusted hosts. Trusted hosts prove identity using values provided by the
TA, while the remaining hosts prove identity using values provided by a
trusted host and certificate trails that end on that host. The name of a
trusted host is also the name of its sugroup and also the subject and issuer
name on its trusted certificate. The TA is not necessarily a trusted host in
this sense, but often is.
In some schemes there are separate keys for servers and clients. A server can
also be a client of another server, but a client can never be a server for
another client. In general, trusted hosts and nontrusted hosts that operate as
both server and client have parameter files that contain both server and
client keys. Hosts that operate only as clients have key files that contain
only client keys.
The PC scheme supports only one trusted host in the group. On trusted host alice
run
ntp-keygen -P -p
password to generate the host key file
ntpkey_RSAkey_alice.filestamp and
trusted private certificate file
ntpkey_RSA-MD5_cert_alice.filestamp.
Copy both files to all group hosts; they replace the files which would be
generated in other schemes. On each host bob install a soft link from the
generic name
ntpkey_host_bob to the
host key file and soft link
ntpkey_cert_bob to the private
certificate file. Note the generic links are on bob, but point to files
generated by trusted host alice. In this scheme it is not possible to refresh
either the keys or certificates without copying them to all other hosts in the
group.
For the IFF scheme proceed as in the TC scheme to generate keys and certificates
for all group hosts, then for every trusted host in the group, generate the
IFF parameter file. On trusted host alice run
ntp-keygen
-T -I -p
password to produce her parameter file
ntpkey_IFFpar_alice.filestamp, which
includes both server and client keys. Copy this file to all group hosts that
operate as both servers and clients and install a soft link from the generic
ntpkey_iff_alice to this file. If
there are no hosts restricted to operate only as clients, there is nothing
further to do. As the IFF scheme is independent of keys and certificates,
these files can be refreshed as needed.
If a rogue client has the parameter file, it could masquerade as a legitimate
server and present a middleman threat. To eliminate this threat, the client
keys can be extracted from the parameter file and distributed to all
restricted clients. After generating the parameter file, on alice run
ntp-keygen -e and pipe the output to a
file or mail program. Copy or mail this file to all restricted clients. On
these clients install a soft link from the generic
ntpkey_iff_alice to this file. To
further protect the integrity of the keys, each file can be encrypted with a
secret password.
For the GQ scheme proceed as in the TC scheme to generate keys and certificates
for all group hosts, then for every trusted host in the group, generate the
IFF parameter file. On trusted host alice run
ntp-keygen
-T -G -p
password to produce her parameter file
ntpkey_GQpar_alice.filestamp, which
includes both server and client keys. Copy this file to all group hosts and
install a soft link from the generic
ntpkey_gq_alice to this file. In
addition, on each host bob install a soft link from generic
ntpkey_gq_bob to this file. As the GQ
scheme updates the GQ parameters file and certificate at the same time, keys
and certificates can be regenerated as needed.
For the MV scheme, proceed as in the TC scheme to generate keys and certificates
for all group hosts. For illustration assume trish is the TA, alice one of
several trusted hosts and bob one of her clients. On TA trish run
ntp-keygen -V n
-p password, where
n is the number of revokable keys (typically 5) to
produce the parameter file
ntpkeys_MVpar_trish.filestamp and
client key files
ntpkeys_MVkeyd_trish.filestamp where
d is the key number (0 <
d <
n). Copy the parameter file to alice and install a soft
link from the generic
ntpkey_mv_alice
to this file. Copy one of the client key files to alice for later distribution
to her clients. It doesn't matter which client key file goes to alice, since
they all work the same way. Alice copies the client key file to all of her
cliens. On client bob install a soft link from generic
ntpkey_mvkey_bob to the client key
file. As the MV scheme is independent of keys and certificates, these files
can be refreshed as needed.
Command Line Options
-
-
- -c
scheme
- Select certificate message digest/signature encryption
scheme. The scheme can be one of the following:
RSA-MD2, RSA-MD5,
RSA-SHA, RSA-SHA1,
RSA-MDC2, RSA-RIPEMD160,
DSA-SHA, or DSA-SHA1. Note that RSA
schemes must be used with a RSA sign key and DSA schemes must be used with
a DSA sign key. The default without this option is
RSA-MD5.
-
-
- -d
- Enable debugging. This option displays the cryptographic
data produced in eye-friendly billboards.
-
-
- -e
- Write the IFF client keys to the standard output. This is
intended for automatic key distribution by mail.
-
-
- -G
- Generate parameters and keys for the GQ identification
scheme, obsoleting any that may exist.
-
-
- -g
- Generate keys for the GQ identification scheme using the
existing GQ parameters. If the GQ parameters do not yet exist, create them
first.
-
-
- -H
- Generate new host keys, obsoleting any that may exist.
-
-
- -I
- Generate parameters for the IFF identification scheme,
obsoleting any that may exist.
-
-
- -i
name
- Set the suject name to name. This is
used as the subject field in certificates and in the file name for host
and sign keys.
-
-
- -M
- Generate MD5 keys, obsoleting any that may exist.
-
-
- -P
- Generate a private certificate. By default, the program
generates public certificates.
-
-
- -p
password
- Encrypt generated files containing private data with
password and the DES-CBC algorithm.
-
-
- -q
- Set the password for reading files to password.
-
-
- -S
[RSA | DSA]
- Generate a new sign key of the designated type, obsoleting
any that may exist. By default, the program uses the host key as the sign
key.
-
-
- -s
name
- Set the issuer name to name. This is
used for the issuer field in certificates and in the file name for
identity files.
-
-
- -T
- Generate a trusted certificate. By default, the program
generates a non-trusted certificate.
-
-
- -V
nkeys
- Generate parameters and keys for the Mu-Varadharajan (MV)
identification scheme.
Random Seed File
All cryptographically sound key generation schemes must have means to randomize
the entropy seed used to initialize the internal pseudo-random number
generator used by the library routines. The OpenSSL library uses a designated
random seed file for this purpose. The file must be available when starting
the NTP daemon and
ntp-keygen program. If a site supports
OpenSSL or its companion OpenSSH, it is very likely that means to do this are
already available.
It is important to understand that entropy must be evolved for each generation,
for otherwise the random number sequence would be predictable. Various means
dependent on external events, such as keystroke intervals, can be used to do
this and some systems have built-in entropy sources. Suitable means are
described in the OpenSSL software documentation, but are outside the scope of
this page.
The entropy seed used by the OpenSSL library is contained in a file, usually
called
.rnd, which must be available when starting the NTP
daemon or the
ntp-keygen program. The NTP daemon will first
look for the file using the path specified by the
randfile
subcommand of the
crypto configuration command. If not
specified in this way, or when starting the
ntp-keygen
program, the OpenSSL library will look for the file using the path specified
by the
RANDFILE
environment variable in the user home
directory, whether root or some other user. If the
RANDFILE
environment variable is not present, the
library will look for the
.rnd file in the user home
directory. If the file is not available or cannot be written, the daemon exits
with a message to the system log and the program exits with a suitable error
message.
Cryptographic Data Files
All other file formats begin with two lines. The first contains the file name,
including the generated host name and filestamp. The second contains the
datestamp in conventional Unix date format. Lines beginning with # are
considered comments and ignored by the
ntp-keygen program
and
ntpd(8) daemon. Cryptographic
values are encoded first using ASN.1 rules, then encrypted if necessary, and
finally written PEM-encoded printable ASCII format preceded and followed by
MIME content identifier lines.
The format of the symmetric keys file is somewhat different than the other files
in the interest of backward compatibility. Since DES-CBC is deprecated in
NTPv4, the only key format of interest is MD5 alphanumeric strings. Following
hte heard the keys are entered one per line in the format
keyno type key
where
keyno is a positive integer in the range 1-65,535,
type is the string MD5 defining the key format and
key is the key itself, which is a printable ASCII string
16 characters or less in length. Each character is chosen from the 93
printable characters in the range 0x21 through 0x7f excluding space and the
‘
#
’ character.
Note that the keys used by the
ntpq(8) and
ntpdc(8) programs are checked
against passwords requested by the programs and entered by hand, so it is
generally appropriate to specify these keys in human readable ASCII format.
The
ntp-keygen program generates a MD5 symmetric keys file
ntpkey_MD5key_hostname.filestamp.
Since the file contains private shared keys, it should be visible only to root
and distributed by secure means to other subnet hosts. The NTP daemon loads
the file
ntp.keys, so
ntp-keygen installs
a soft link from this name to the generated file. Subsequently, similar soft
links must be installed by manual or automated means on the other subnet
hosts. While this file is not used with the Autokey Version 2 protocol, it is
needed to authenticate some remote configuration commands used by the
ntpq(8) and
ntpdc(8) utilities.
OPTIONS
-
-
- -b imbits,
--imbits=imbits
- identity modulus bits. This option takes an integer number
as its argument. The value of imbits is constrained
to being: in the range 256 through 2048
The number of bits in the identity modulus. The default is 256.
-
-
- -c scheme,
--certificate=scheme
- certificate scheme.
scheme is one of RSA-MD2, RSA-MD5, RSA-SHA, RSA-SHA1, RSA-MDC2,
RSA-RIPEMD160, DSA-SHA, or DSA-SHA1.
Select the certificate message digest/signature encryption scheme. Note that
RSA schemes must be used with a RSA sign key and DSA schemes must be used
with a DSA sign key. The default without this option is RSA-MD5.
-
-
- -C cipher,
--cipher=cipher
- privatekey cipher.
Select the cipher which is used to encrypt the files containing private
keys. The default is three-key triple DES in CBC mode, equivalent to
"@code{-C des-ede3-cbc". The openssl tool lists ciphers
available in " openssl -h" output.
-
-
- -d, --debug-level
- Increase debug verbosity level. This option may appear an
unlimited number of times.
-
-
- -D number,
--set-debug-level=number
- Set the debug verbosity level. This option may appear an
unlimited number of times. This option takes an integer number as its
argument.
-
-
- -e, --id-key
- Write IFF or GQ identity keys.
Write the IFF or GQ client keys to the standard output. This is intended for
automatic key distribution by mail.
-
-
- -G, --gq-params
- Generate GQ parameters and keys.
Generate parameters and keys for the GQ identification scheme, obsoleting
any that may exist.
-
-
- -H, --host-key
- generate RSA host key.
Generate new host keys, obsoleting any that may exist.
-
-
- -I, --iffkey
- generate IFF parameters.
Generate parameters for the IFF identification scheme, obsoleting any that
may exist.
-
-
- -i group,
--ident=group
- set Autokey group name.
Set the optional Autokey group name to name. This is used in the file name
of IFF, GQ, and MV client parameters files. In that role, the default is
the host name if this option is not provided. The group name, if specified
using -i/--ident or using -s/--subject-name following an
'@' character, is also a part of the self-signed host certificate's
subject and issuer names in the form host@group and should match
the ´ crypto ident' or 'server ident' configuration in
ntpd's configuration file.
-
-
- -l lifetime,
--lifetime=lifetime
- set certificate lifetime. This option takes an integer
number as its argument.
Set the certificate expiration to lifetime days from now.
-
-
- -M, --md5key
- generate MD5 keys.
Generate MD5 keys, obsoleting any that may exist.
-
-
- -m modulus,
--modulus=modulus
- modulus. This option takes an integer number as its
argument. The value of modulus is constrained to
being: in the range 256 through 2048
The number of bits in the prime modulus. The default is 512.
-
-
- -P, --pvt-cert
- generate PC private certificate.
Generate a private certificate. By default, the program generates public
certificates.
-
-
- -p passwd,
--pvt-passwd=passwd
- output private password.
Encrypt generated files containing private data with the specified password
and the cipher selected with -C/--cipher.
-
-
- -q passwd,
--get-pvt-passwd=passwd
- input private password.
Set the password for reading files to the specified password.
-
-
- -S sign,
--sign-key=sign
- generate sign key (RSA or DSA).
Generate a new sign key of the designated type, obsoleting any that may
exist. By default, the program uses the host key as the sign key.
-
-
- -s host@group,
--subject-name=host@group
- set host and optionally group name.
Set the Autokey host name, and optionally, group name specified following an
' @' character. The host name is used in the file name of generated
host and signing certificates, without the group name. The host name, and
if provided, group name are used in host@group form for the host
certificate's subject and issuer fields. Specifying ' -s @group' is
allowed, and results in leaving the host name unchanged while appending
@group to the subject and issuer fields, as with -i group.
The group name, or if not provided, the host name are also used in the
file names of IFF, GQ, and MV client parameter files.
-
-
- -T, --trusted-cert
- trusted certificate (TC scheme).
Generate a trusted certificate. By default, the program generates a
non-trusted certificate.
-
-
- -V num,
--mv-params=num
- generate <num> MV parameters. This option takes an
integer number as its argument.
Generate parameters and keys for the Mu-Varadharajan (MV) identification
scheme.
-
-
- -v num,
--mv-keys=num
- update <num> MV keys. This option takes an integer
number as its argument.
This option has not been fully documented.
-
-
- -?, --help
- Display usage information and exit.
-
-
- -!, --more-help
- Pass the extended usage information through a pager.
-
-
- ->
[cfgfile],
--save-opts
[=cfgfile]
- Save the option state to cfgfile. The default is the
last configuration file listed in the OPTION PRESETS
section, below. The command will exit after updating the config file.
-
-
- -< cfgfile,
--load-opts=cfgfile,
--no-load-opts
- Load options from cfgfile. The no-load-opts
form will disable the loading of earlier config/rc/ini files.
--no-load-opts is handled early, out of order.
-
-
- --version
[{v|c|n}]
- Output version of program and exit. The default mode is
`v', a simple version. The `c' mode will print copyright information and
`n' will print the full copyright notice.
OPTION PRESETS
Any option that is not marked as
not presettable may be preset by loading
values from configuration ("RC" or ".INI") file(s) and
values from environment variables named:
NTP_KEYGEN_<option-name> or
NTP_KEYGEN The environmental
presets take precedence (are processed later than) the configuration files.
The
homerc files are "
$HOME", and
"
.". If any of these are directories, then the file
.ntprc is searched for within those directories.
cvt_prog='/usr/local/gnu/share/autogen/texi2mdoc' cvt_prog=`cd `dirname
"$cvt_prog"` >/dev/null && pwd
`/`basename "$cvt_prog"` cd $tmp_dir test -x "$cvt_prog" ||
die "'$cvt_prog' is not executable" {
list='synopsis description options option-presets'
for f in $list ; do cat $f ; echo ; done
rm -f $list name
list='implementation-notes environment files examples exit-status errors
compatibility see-also conforming-to history authors copyright bugs
notes'
for f in $list ; do cat $f ; echo ; done > .end-doc
rm -f $list
list=`ls -1 *`' .end-doc'
for f in $list ; do cat $f ; echo ; done
rm -f $list } 1>.doc 2>/dev/null sed -f .cmds .doc |
/usr/local/gnu/bin/grep -E -v '^[ ]*$' | $cvt_prog
USAGE
The
-p password option specifies the
write password and
-q password option
the read password for previously encrypted files. The
ntp-keygen program prompts for the password if it reads an
encrypted file and the password is missing or incorrect. If an encrypted file
is read successfully and no write password is specified, the read password is
used as the write password by default.
ENVIRONMENT
See
OPTION PRESETS for configuration environment variables.
FILES
See
OPTION PRESETS for configuration files.
EXIT STATUS
One of the following exit values will be returned:
-
-
- 0 (EXIT_SUCCESS)
- Successful program execution.
-
-
- 1 (EXIT_FAILURE)
- The operation failed or the command syntax was not
valid.
-
-
- 66 (EX_NOINPUT)
- A specified configuration file could not be loaded.
-
-
- 70 (EX_SOFTWARE)
- libopts had an internal operational error. Please report it
to autogen-users@lists.sourceforge.net. Thank you.
AUTHORS
The University of Delaware
COPYRIGHT
Copyright (C) 1970-2013 The University of Delaware all rights reserved. This
program is released under the terms of the NTP license,
<http://ntp.org/license>.
BUGS
It can take quite a while to generate some cryptographic values, from one to
several minutes with modern architectures such as UltraSPARC and up to tens of
minutes to an hour with older architectures such as SPARC IPC.
Please report bugs to http://bugs.ntp.org .
Please send bug reports to: http://bugs.ntp.org, bugs@ntp.org
NOTES
This document corresponds to version 4.2.7p404 of NTP. Portions of this document
came from FreeBSD.
This manual page was
AutoGen-erated from the
ntp-keygen option
definitions.