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     22       1.1  christos <h1 class="settitle">Ntp-keygen User's Manual</h1>
     23       1.1  christos   <div class="shortcontents">
     24       1.1  christos <h2>Short Contents</h2>
     25       1.1  christos <ul>
     26       1.1  christos <a href="#Top">Top</a>
     27       1.1  christos <a href="#Top">NTP Key Generation Program User Manual</a>
     28       1.1  christos </ul>
     29       1.1  christos </div>
     30       1.1  christos 
     31       1.1  christos 
     32       1.1  christos 
     33       1.1  christos <div class="node">
     34       1.1  christos <p><hr>
     35   1.1.1.7  christos <a name="Top"></a>Up:&nbsp;<a rel="up" accesskey="u" href="#dir">(dir)</a>
     36   1.1.1.7  christos <br>
     37       1.1  christos </div>
     38       1.1  christos 
     39       1.1  christos <h2 class="unnumbered">Top</h2>
     40       1.1  christos 
     41       1.1  christos <ul class="menu">
     42       1.1  christos <li><a accesskey="1" href="#Description">Description</a>
     43       1.1  christos <li><a accesskey="2" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a>: 	Invoking ntp-keygen
     44       1.1  christos <li><a accesskey="3" href="#Running-the-Program">Running the Program</a>
     45       1.1  christos <li><a accesskey="4" href="#Random-Seed-File">Random Seed File</a>
     46       1.1  christos <li><a accesskey="5" href="#Cryptographic-Data-Files">Cryptographic Data Files</a>
     47       1.1  christos </ul>
     48       1.1  christos 
     49       1.1  christos <div class="node">
     50       1.1  christos <p><hr>
     51   1.1.1.7  christos <a name="Top"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Description">Description</a>,
     52       1.1  christos Previous:&nbsp;<a rel="previous" accesskey="p" href="#dir">(dir)</a>,
     53       1.1  christos Up:&nbsp;<a rel="up" accesskey="u" href="#dir">(dir)</a>
     54   1.1.1.7  christos <br>
     55       1.1  christos </div>
     56       1.1  christos 
     57       1.1  christos <h2 class="unnumbered">NTP Key Generation Program User Manual</h2>
     58       1.1  christos 
     59       1.1  christos <p>This document describes the use of the NTP Project's <code>ntp-keygen</code>
     60       1.1  christos program, that generates cryptographic data files used by the NTPv4
     61       1.1  christos authentication and identity schemes. 
     62       1.1  christos It can generate message digest keys used in symmetric key cryptography and,
     63       1.1  christos if the OpenSSL software
     64       1.1  christos library has been installed, it can generate host keys, sign keys,
     65       1.1  christos certificates, and identity keys and parameters used by the Autokey
     66       1.1  christos public key cryptography. 
     67       1.1  christos The message digest keys file is generated in a
     68       1.1  christos format compatible with NTPv3. 
     69       1.1  christos All other files are in PEM-encoded
     70       1.1  christos printable ASCII format so they can be embedded as MIME attachments in
     71       1.1  christos mail to other sites.
     72       1.1  christos 
     73  1.1.1.12  christos   <p>This document applies to version 4.2.8p12 of <code>ntp-keygen</code>.
     74       1.1  christos 
     75       1.1  christos <div class="node">
     76       1.1  christos <p><hr>
     77   1.1.1.7  christos <a name="Description"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Running-the-Program">Running the Program</a>,
     78       1.1  christos Previous:&nbsp;<a rel="previous" accesskey="p" href="#Top">Top</a>,
     79       1.1  christos Up:&nbsp;<a rel="up" accesskey="u" href="#Top">Top</a>
     80   1.1.1.7  christos <br>
     81       1.1  christos </div>
     82       1.1  christos 
     83       1.1  christos <!-- node-name,  next,  previous,  up -->
     84       1.1  christos <h3 class="section">Description</h3>
     85       1.1  christos 
     86       1.1  christos <p>This program generates cryptographic data files used by the NTPv4
     87       1.1  christos authentication and identity schemes. It can generate message digest
     88       1.1  christos keys used in symmetric key cryptography and, if the OpenSSL software
     89       1.1  christos library has been installed, it can generate host keys, sign keys,
     90       1.1  christos certificates, and identity keys and parameters used by the Autokey
     91       1.1  christos public key cryptography. The message digest keys file is generated in a
     92       1.1  christos format compatible with NTPv3. All other files are in PEM-encoded
     93       1.1  christos printable ASCII format so they can be embedded as MIME attachments in
     94       1.1  christos mail to other sites.
     95       1.1  christos 
     96       1.1  christos   <p>When used to generate message digest keys, the program produces a file
     97       1.1  christos containing ten pseudo-random printable ASCII strings suitable for the
     98       1.1  christos MD5 message digest algorithm included in the distribution. 
     99       1.1  christos If the
    100       1.1  christos OpenSSL library is installed, it produces an additional ten hex-encoded
    101       1.1  christos random bit strings suitable for the SHA1 and other message digest
    102       1.1  christos algorithms. 
    103       1.1  christos The message digest keys file must be distributed and stored
    104       1.1  christos using secure means beyond the scope of NTP itself. 
    105       1.1  christos Besides the keys
    106       1.1  christos used for ordinary NTP associations, additional keys can be defined as
    107       1.1  christos passwords for the ntpq and ntpdc utility programs.
    108       1.1  christos 
    109       1.1  christos   <p>The remaining generated files are compatible with other OpenSSL
    110       1.1  christos applications and other Public Key Infrastructure (PKI) resources. 
    111       1.1  christos Certificates generated by this program are compatible with extant
    112       1.1  christos industry practice, although some users might find the interpretation of
    113       1.1  christos X509v3 extension fields somewhat liberal. 
    114       1.1  christos However, the identity keys
    115       1.1  christos are probably not compatible with anything other than Autokey.
    116       1.1  christos 
    117       1.1  christos   <p>Some files used by this program are encrypted using a private password. 
    118       1.1  christos The <code>-p</code> option specifies the password for local encrypted files and the
    119       1.1  christos <code>-q</code> option the password for encrypted files sent to remote sites. 
    120       1.1  christos If no password is specified, the host name returned by the Unix
    121       1.1  christos <code>gethostname()</code> function, normally the DNS name of the host, is used.
    122       1.1  christos 
    123       1.1  christos   <p>The <kbd>pw</kbd> option of the <code>crypto</code> configuration command
    124       1.1  christos specifies the read password for previously encrypted local files. 
    125       1.1  christos This must match the local password used by this program. 
    126       1.1  christos If not specified, the host name is used. 
    127       1.1  christos Thus, if files are generated by this program without password,
    128       1.1  christos they can be read back by ntpd without password, but only on the same
    129       1.1  christos host.
    130       1.1  christos 
    131       1.1  christos   <p>Normally, encrypted files for each host are generated by that host and
    132       1.1  christos used only by that host, although exceptions exist as noted later on
    133       1.1  christos this page. 
    134       1.1  christos The symmetric keys file, normally called <code>ntp.keys</code>, is
    135       1.1  christos usually installed in <code>/etc</code>. 
    136       1.1  christos Other files and links are usually installed
    137       1.1  christos in <code>/usr/local/etc</code>, which is normally in a shared filesystem in
    138       1.1  christos NFS-mounted networks and cannot be changed by shared clients. 
    139       1.1  christos The location of the keys directory can be changed by the keysdir
    140       1.1  christos configuration command in such cases. 
    141       1.1  christos Normally, this is in <code>/etc</code>.
    142       1.1  christos 
    143       1.1  christos   <p>This program directs commentary and error messages to the standard
    144       1.1  christos error stream <code>stderr</code> and remote files to the standard output stream
    145       1.1  christos <code>stdout</code> where they can be piped to other applications or redirected to
    146       1.1  christos files. 
    147       1.1  christos The names used for generated files and links all begin with the
    148       1.1  christos string <code>ntpkey</code> and include the file type,
    149       1.1  christos generating host and filestamp,
    150       1.1  christos as described in the <a href="#Cryptographic-Data-Files">Cryptographic Data Files</a> section below.
    151       1.1  christos 
    152       1.1  christos <div class="node">
    153       1.1  christos <p><hr>
    154   1.1.1.7  christos <a name="Running-the-Program"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Random-Seed-File">Random Seed File</a>,
    155       1.1  christos Previous:&nbsp;<a rel="previous" accesskey="p" href="#Description">Description</a>,
    156       1.1  christos Up:&nbsp;<a rel="up" accesskey="u" href="#Top">Top</a>
    157   1.1.1.7  christos <br>
    158       1.1  christos </div>
    159       1.1  christos 
    160       1.1  christos <!-- node-name,  next,  previous,  up -->
    161       1.1  christos <h3 class="section">Running the Program</h3>
    162       1.1  christos 
    163       1.1  christos <p>To test and gain experience with Autokey concepts, log in as root and
    164       1.1  christos change to the keys directory, usually <code>/usr/local/etc</code>. 
    165       1.1  christos When run for the
    166       1.1  christos first time, or if all files with names beginning <code>ntpkey</code>] have been
    167       1.1  christos removed, use the <code>ntp-keygen</code> command without arguments to generate a
    168       1.1  christos default RSA host key and matching RSA-MD5 certificate with expiration
    169       1.1  christos date one year hence. 
    170       1.1  christos If run again without options, the program uses the
    171       1.1  christos existing keys and parameters and generates only a new certificate with
    172       1.1  christos new expiration date one year hence.
    173       1.1  christos 
    174       1.1  christos   <p>Run the command on as many hosts as necessary. 
    175       1.1  christos Designate one of them as the trusted host (TH) using <code>ntp-keygen</code>
    176       1.1  christos with the <code>-T</code> option and configure
    177       1.1  christos it to synchronize from reliable Internet servers. 
    178       1.1  christos Then configure the other hosts to synchronize to the TH directly or indirectly. 
    179       1.1  christos A certificate trail is created when Autokey asks the immediately
    180       1.1  christos ascendant host towards the TH to sign its certificate, which is then
    181       1.1  christos provided to the immediately descendant host on request. 
    182       1.1  christos All group hosts should have acyclic certificate trails ending on the TH.
    183       1.1  christos 
    184       1.1  christos   <p>The host key is used to encrypt the cookie when required and so must be
    185       1.1  christos RSA type. 
    186       1.1  christos By default, the host key is also the sign key used to encrypt signatures. 
    187       1.1  christos A different sign key can be assigned using the <code>-S</code> option
    188       1.1  christos and this can be either RSA or DSA type. 
    189       1.1  christos By default, the signature
    190       1.1  christos message digest type is MD5, but any combination of sign key type and
    191       1.1  christos message digest type supported by the OpenSSL library can be specified
    192       1.1  christos using the <code>-c</code> option.
    193       1.1  christos 
    194       1.1  christos   <p>The rules say cryptographic media should be generated with proventic
    195       1.1  christos filestamps, which means the host should already be synchronized before
    196       1.1  christos this program is run. 
    197       1.1  christos This of course creates a chicken-and-egg problem
    198       1.1  christos when the host is started for the first time. 
    199       1.1  christos Accordingly, the host time
    200       1.1  christos should be set by some other means, such as eyeball-and-wristwatch, at
    201       1.1  christos least so that the certificate lifetime is within the current year. 
    202       1.1  christos After that and when the host is synchronized to a proventic source, the
    203       1.1  christos certificate should be re-generated.
    204       1.1  christos 
    205       1.1  christos   <p>Additional information on trusted groups and identity schemes is on the
    206       1.1  christos Autokey Public-Key Authentication page.
    207       1.1  christos 
    208       1.1  christos <div class="node">
    209       1.1  christos <p><hr>
    210       1.1  christos <a name="ntp_002dkeygen-Invocation"></a>
    211   1.1.1.7  christos <br>
    212       1.1  christos </div>
    213       1.1  christos 
    214       1.1  christos <h3 class="section">Invoking ntp-keygen</h3>
    215       1.1  christos 
    216       1.1  christos <p><a name="index-ntp_002dkeygen-1"></a><a name="index-Create-a-NTP-host-key-2"></a>
    217       1.1  christos 
    218       1.1  christos   <p>This program generates cryptographic data files used by the NTPv4
    219       1.1  christos authentication and identification schemes. 
    220  1.1.1.11  christos It can generate message digest keys used in symmetric key cryptography and,
    221  1.1.1.11  christos if the OpenSSL software library has been installed, it can generate host keys,
    222  1.1.1.11  christos signing keys, certificates, and identity keys and parameters used in Autokey
    223  1.1.1.11  christos public key cryptography. 
    224       1.1  christos These files are used for cookie encryption,
    225  1.1.1.11  christos digital signature, and challenge/response identification algorithms
    226       1.1  christos compatible with the Internet standard security infrastructure.
    227       1.1  christos 
    228  1.1.1.11  christos   <p>The message digest symmetric keys file is generated in a format
    229  1.1.1.11  christos compatible with NTPv3. 
    230  1.1.1.11  christos All other files are in PEM-encoded printable ASCII format,
    231  1.1.1.11  christos so they can be embedded as MIME attachments in email to other sites
    232       1.1  christos and certificate authorities. 
    233       1.1  christos By default, files are not encrypted.
    234       1.1  christos 
    235  1.1.1.11  christos   <p>When used to generate message digest symmetric keys, the program
    236  1.1.1.11  christos produces a file containing ten pseudo-random printable ASCII strings
    237  1.1.1.11  christos suitable for the MD5 message digest algorithm included in the
    238  1.1.1.11  christos distribution. 
    239       1.1  christos If the OpenSSL library is installed, it produces an additional ten
    240  1.1.1.11  christos hex-encoded random bit strings suitable for SHA1, AES-128-CMAC, and
    241  1.1.1.11  christos other message digest algorithms. 
    242  1.1.1.11  christos The message digest symmetric keys file must be distributed and stored
    243       1.1  christos using secure means beyond the scope of NTP itself. 
    244       1.1  christos Besides the keys used for ordinary NTP associations, additional keys
    245       1.1  christos can be defined as passwords for the
    246       1.1  christos <code>ntpq(1ntpqmdoc)</code>
    247       1.1  christos and
    248       1.1  christos <code>ntpdc(1ntpdcmdoc)</code>
    249       1.1  christos utility programs.
    250       1.1  christos 
    251       1.1  christos   <p>The remaining generated files are compatible with other OpenSSL
    252       1.1  christos applications and other Public Key Infrastructure (PKI) resources. 
    253       1.1  christos Certificates generated by this program are compatible with extant
    254       1.1  christos industry practice, although some users might find the interpretation of
    255       1.1  christos X509v3 extension fields somewhat liberal. 
    256       1.1  christos However, the identity keys are probably not compatible with anything
    257       1.1  christos other than Autokey.
    258       1.1  christos 
    259       1.1  christos   <p>Some files used by this program are encrypted using a private password. 
    260       1.1  christos The
    261       1.1  christos <code>-p</code>
    262  1.1.1.11  christos option specifies the read password for local encrypted files and the
    263       1.1  christos <code>-q</code>
    264  1.1.1.11  christos option the write password for encrypted files sent to remote sites. 
    265       1.1  christos If no password is specified, the host name returned by the Unix
    266  1.1.1.11  christos <code>hostname(1)</code>
    267  1.1.1.11  christos command, normally the DNS name of the host, is used as the the default read
    268  1.1.1.11  christos password, for convenience. 
    269  1.1.1.11  christos The
    270  1.1.1.11  christos <code>ntp-keygen</code>
    271  1.1.1.11  christos program prompts for the password if it reads an encrypted file
    272  1.1.1.11  christos and the password is missing or incorrect. 
    273  1.1.1.11  christos If an encrypted file is read successfully and
    274  1.1.1.11  christos no write password is specified, the read password is used
    275  1.1.1.11  christos as the write password by default.
    276       1.1  christos 
    277       1.1  christos   <p>The
    278  1.1.1.11  christos <code>pw</code>
    279       1.1  christos option of the
    280  1.1.1.11  christos <code>crypto</code>
    281  1.1.1.11  christos <code>ntpd(1ntpdmdoc)</code>
    282       1.1  christos configuration command specifies the read
    283       1.1  christos password for previously encrypted local files. 
    284  1.1.1.11  christos This must match the local read password used by this program. 
    285       1.1  christos If not specified, the host name is used. 
    286  1.1.1.11  christos Thus, if files are generated by this program without an explicit password,
    287       1.1  christos they can be read back by
    288  1.1.1.11  christos <code>ntpd(1ntpdmdoc)</code>
    289  1.1.1.11  christos without specifying an explicit password but only on the same host. 
    290  1.1.1.11  christos If the write password used for encryption is specified as the host name,
    291  1.1.1.11  christos these files can be read by that host with no explicit password.
    292       1.1  christos 
    293       1.1  christos   <p>Normally, encrypted files for each host are generated by that host and
    294       1.1  christos used only by that host, although exceptions exist as noted later on
    295       1.1  christos this page. 
    296       1.1  christos The symmetric keys file, normally called
    297  1.1.1.11  christos <span class="file">ntp.keys</span>,
    298       1.1  christos is usually installed in
    299   1.1.1.7  christos <span class="file">/etc</span>. 
    300       1.1  christos Other files and links are usually installed in
    301   1.1.1.7  christos <span class="file">/usr/local/etc</span>,
    302       1.1  christos which is normally in a shared filesystem in
    303       1.1  christos NFS-mounted networks and cannot be changed by shared clients. 
    304  1.1.1.11  christos In these cases, NFS clients can specify the files in another
    305  1.1.1.11  christos directory such as
    306  1.1.1.11  christos <span class="file">/etc</span>
    307  1.1.1.11  christos using the
    308  1.1.1.11  christos <code>keysdir</code>
    309  1.1.1.11  christos <code>ntpd(1ntpdmdoc)</code>
    310  1.1.1.11  christos configuration file command.
    311       1.1  christos 
    312       1.1  christos   <p>This program directs commentary and error messages to the standard
    313       1.1  christos error stream
    314  1.1.1.11  christos <span class="file">stderr</span>
    315       1.1  christos and remote files to the standard output stream
    316  1.1.1.11  christos <span class="file">stdout</span>
    317       1.1  christos where they can be piped to other applications or redirected to files. 
    318       1.1  christos The names used for generated files and links all begin with the
    319       1.1  christos string
    320  1.1.1.11  christos <span class="file">ntpkey*</span>
    321       1.1  christos and include the file type, generating host and filestamp,
    322       1.1  christos as described in the
    323  1.1.1.11  christos <a href="#Cryptographic-Data-Files">Cryptographic Data Files</a>
    324       1.1  christos section below.
    325       1.1  christos 
    326       1.1  christos <h5 class="subsubsection">Running the Program</h5>
    327       1.1  christos 
    328       1.1  christos <p>The safest way to run the
    329       1.1  christos <code>ntp-keygen</code>
    330       1.1  christos program is logged in directly as root. 
    331  1.1.1.11  christos The recommended procedure is change to the
    332  1.1.1.11  christos <kbd>keys</kbd>
    333  1.1.1.11  christos directory, usually
    334   1.1.1.7  christos <span class="file">/usr/local/etc</span>,
    335  1.1.1.11  christos then run the program.
    336  1.1.1.11  christos 
    337  1.1.1.11  christos   <p>To test and gain experience with Autokey concepts, log in as root and
    338  1.1.1.11  christos change to the
    339  1.1.1.11  christos <kbd>keys</kbd>
    340  1.1.1.11  christos directory, usually
    341  1.1.1.11  christos <span class="file">/usr/local/etc</span>. 
    342  1.1.1.11  christos When run for the first time, or if all files with names beginning with
    343  1.1.1.11  christos <span class="file">ntpkey*</span>
    344  1.1.1.11  christos have been removed, use the
    345  1.1.1.11  christos <code>ntp-keygen</code>
    346  1.1.1.11  christos command without arguments to generate a default
    347  1.1.1.11  christos <code>RSA</code>
    348  1.1.1.11  christos host key and matching
    349  1.1.1.11  christos <code>RSA-MD5</code>
    350  1.1.1.11  christos certificate file with expiration date one year hence,
    351       1.1  christos which is all that is necessary in many cases. 
    352       1.1  christos The program also generates soft links from the generic names
    353       1.1  christos to the respective files. 
    354  1.1.1.11  christos If run again without options, the program uses the
    355  1.1.1.11  christos existing keys and parameters and generates a new certificate file with
    356  1.1.1.11  christos new expiration date one year hence, and soft link.
    357       1.1  christos 
    358  1.1.1.11  christos   <p>The host key is used to encrypt the cookie when required and so must be
    359  1.1.1.11  christos <code>RSA</code>
    360  1.1.1.11  christos type. 
    361       1.1  christos By default, the host key is also the sign key used to encrypt signatures. 
    362       1.1  christos When necessary, a different sign key can be specified and this can be
    363  1.1.1.11  christos either
    364  1.1.1.11  christos <code>RSA</code>
    365  1.1.1.11  christos or
    366  1.1.1.11  christos <code>DSA</code>
    367  1.1.1.11  christos type. 
    368  1.1.1.11  christos By default, the message digest type is
    369  1.1.1.11  christos <code>MD5</code>,
    370  1.1.1.11  christos but any combination
    371       1.1  christos of sign key type and message digest type supported by the OpenSSL library
    372  1.1.1.11  christos can be specified, including those using the
    373  1.1.1.11  christos <code>AES128CMAC</code>, <code>MD2</code>, <code>MD5</code>, <code>MDC2</code>, <code>SHA</code>, <code>SHA1</code>
    374  1.1.1.11  christos and
    375  1.1.1.11  christos <code>RIPE160</code>
    376  1.1.1.11  christos message digest algorithms. 
    377       1.1  christos However, the scheme specified in the certificate must be compatible
    378       1.1  christos with the sign key. 
    379  1.1.1.11  christos Certificates using any digest algorithm are compatible with
    380  1.1.1.11  christos <code>RSA</code>
    381  1.1.1.11  christos sign keys;
    382  1.1.1.11  christos however, only
    383  1.1.1.11  christos <code>SHA</code>
    384  1.1.1.11  christos and
    385  1.1.1.11  christos <code>SHA1</code>
    386  1.1.1.11  christos certificates are compatible with
    387  1.1.1.11  christos <code>DSA</code>
    388  1.1.1.11  christos sign keys.
    389       1.1  christos 
    390       1.1  christos   <p>Private/public key files and certificates are compatible with
    391       1.1  christos other OpenSSL applications and very likely other libraries as well. 
    392       1.1  christos Certificates or certificate requests derived from them should be compatible
    393       1.1  christos with extant industry practice, although some users might find
    394       1.1  christos the interpretation of X509v3 extension fields somewhat liberal. 
    395       1.1  christos However, the identification parameter files, although encoded
    396       1.1  christos as the other files, are probably not compatible with anything other than Autokey.
    397       1.1  christos 
    398       1.1  christos   <p>Running the program as other than root and using the Unix
    399  1.1.1.11  christos <code>su(1)</code>
    400       1.1  christos command
    401       1.1  christos to assume root may not work properly, since by default the OpenSSL library
    402       1.1  christos looks for the random seed file
    403  1.1.1.11  christos <span class="file">.rnd</span>
    404       1.1  christos in the user home directory. 
    405       1.1  christos However, there should be only one
    406  1.1.1.11  christos <span class="file">.rnd</span>,
    407       1.1  christos most conveniently
    408       1.1  christos in the root directory, so it is convenient to define the
    409  1.1.1.11  christos .Ev RANDFILE
    410       1.1  christos environment variable used by the OpenSSL library as the path to
    411  1.1.1.11  christos <span class="file">.rnd</span>.
    412       1.1  christos 
    413       1.1  christos   <p>Installing the keys as root might not work in NFS-mounted
    414       1.1  christos shared file systems, as NFS clients may not be able to write
    415       1.1  christos to the shared keys directory, even as root. 
    416       1.1  christos In this case, NFS clients can specify the files in another
    417       1.1  christos directory such as
    418   1.1.1.7  christos <span class="file">/etc</span>
    419       1.1  christos using the
    420       1.1  christos <code>keysdir</code>
    421  1.1.1.11  christos <code>ntpd(1ntpdmdoc)</code>
    422  1.1.1.11  christos configuration file command. 
    423       1.1  christos There is no need for one client to read the keys and certificates
    424       1.1  christos of other clients or servers, as these data are obtained automatically
    425       1.1  christos by the Autokey protocol.
    426       1.1  christos 
    427       1.1  christos   <p>Ordinarily, cryptographic files are generated by the host that uses them,
    428       1.1  christos but it is possible for a trusted agent (TA) to generate these files
    429       1.1  christos for other hosts; however, in such cases files should always be encrypted. 
    430       1.1  christos The subject name and trusted name default to the hostname
    431       1.1  christos of the host generating the files, but can be changed by command line options. 
    432       1.1  christos It is convenient to designate the owner name and trusted name
    433       1.1  christos as the subject and issuer fields, respectively, of the certificate. 
    434       1.1  christos The owner name is also used for the host and sign key files,
    435       1.1  christos while the trusted name is used for the identity files.
    436       1.1  christos 
    437       1.1  christos   <p>All files are installed by default in the keys directory
    438   1.1.1.7  christos <span class="file">/usr/local/etc</span>,
    439       1.1  christos which is normally in a shared filesystem
    440       1.1  christos in NFS-mounted networks. 
    441       1.1  christos The actual location of the keys directory
    442       1.1  christos and each file can be overridden by configuration commands,
    443       1.1  christos but this is not recommended. 
    444       1.1  christos Normally, the files for each host are generated by that host
    445       1.1  christos and used only by that host, although exceptions exist
    446       1.1  christos as noted later on this page.
    447       1.1  christos 
    448       1.1  christos   <p>Normally, files containing private values,
    449       1.1  christos including the host key, sign key and identification parameters,
    450       1.1  christos are permitted root read/write-only;
    451       1.1  christos while others containing public values are permitted world readable. 
    452       1.1  christos Alternatively, files containing private values can be encrypted
    453       1.1  christos and these files permitted world readable,
    454       1.1  christos which simplifies maintenance in shared file systems. 
    455  1.1.1.11  christos Since uniqueness is insured by the
    456  1.1.1.11  christos <kbd>hostname</kbd>
    457  1.1.1.11  christos and
    458  1.1.1.11  christos <kbd>filestamp</kbd>
    459  1.1.1.11  christos file name extensions, the files for an NTP server and
    460       1.1  christos dependent clients can all be installed in the same shared directory.
    461       1.1  christos 
    462       1.1  christos   <p>The recommended practice is to keep the file name extensions
    463       1.1  christos when installing a file and to install a soft link
    464       1.1  christos from the generic names specified elsewhere on this page
    465       1.1  christos to the generated files. 
    466       1.1  christos This allows new file generations to be activated simply
    467       1.1  christos by changing the link. 
    468  1.1.1.11  christos If a link is present,
    469  1.1.1.11  christos <code>ntpd(1ntpdmdoc)</code>
    470  1.1.1.11  christos follows it to the file name to extract the
    471  1.1.1.11  christos <kbd>filestamp</kbd>. 
    472       1.1  christos If a link is not present,
    473       1.1  christos <code>ntpd(1ntpdmdoc)</code>
    474  1.1.1.11  christos extracts the
    475  1.1.1.11  christos <kbd>filestamp</kbd>
    476  1.1.1.11  christos from the file itself. 
    477       1.1  christos This allows clients to verify that the file and generation times
    478       1.1  christos are always current. 
    479       1.1  christos The
    480       1.1  christos <code>ntp-keygen</code>
    481  1.1.1.11  christos program uses the same
    482  1.1.1.11  christos <kbd>filestamp</kbd>
    483  1.1.1.11  christos extension for all files generated
    484       1.1  christos at one time, so each generation is distinct and can be readily
    485       1.1  christos recognized in monitoring data.
    486       1.1  christos 
    487  1.1.1.11  christos   <p>Run the command on as many hosts as necessary. 
    488  1.1.1.11  christos Designate one of them as the trusted host (TH) using
    489       1.1  christos <code>ntp-keygen</code>
    490  1.1.1.11  christos with the
    491  1.1.1.11  christos <code>-T</code>
    492  1.1.1.11  christos option and configure it to synchronize from reliable Internet servers. 
    493  1.1.1.11  christos Then configure the other hosts to synchronize to the TH directly or
    494  1.1.1.11  christos indirectly. 
    495  1.1.1.11  christos A certificate trail is created when Autokey asks the immediately
    496  1.1.1.11  christos ascendant host towards the TH to sign its certificate, which is then
    497  1.1.1.11  christos provided to the immediately descendant host on request. 
    498  1.1.1.11  christos All group hosts should have acyclic certificate trails ending on the TH.
    499       1.1  christos 
    500  1.1.1.11  christos   <p>The host key is used to encrypt the cookie when required and so must be
    501  1.1.1.11  christos RSA type. 
    502  1.1.1.11  christos By default, the host key is also the sign key used to encrypt
    503  1.1.1.11  christos signatures. 
    504  1.1.1.11  christos A different sign key can be assigned using the
    505  1.1.1.11  christos <code>-S</code>
    506  1.1.1.11  christos option and this can be either
    507  1.1.1.11  christos <code>RSA</code>
    508  1.1.1.11  christos or
    509  1.1.1.11  christos <code>DSA</code>
    510  1.1.1.11  christos type. 
    511  1.1.1.11  christos By default, the signature
    512  1.1.1.11  christos message digest type is
    513  1.1.1.11  christos <code>MD5</code>,
    514  1.1.1.11  christos but any combination of sign key type and
    515  1.1.1.11  christos message digest type supported by the OpenSSL library can be specified
    516  1.1.1.11  christos using the
    517  1.1.1.11  christos <code>-c</code>
    518  1.1.1.11  christos option.
    519       1.1  christos 
    520  1.1.1.11  christos   <p>The rules say cryptographic media should be generated with proventic
    521  1.1.1.11  christos filestamps, which means the host should already be synchronized before
    522  1.1.1.11  christos this program is run. 
    523  1.1.1.11  christos This of course creates a chicken-and-egg problem
    524  1.1.1.11  christos when the host is started for the first time. 
    525  1.1.1.11  christos Accordingly, the host time
    526  1.1.1.11  christos should be set by some other means, such as eyeball-and-wristwatch, at
    527  1.1.1.11  christos least so that the certificate lifetime is within the current year. 
    528  1.1.1.11  christos After that and when the host is synchronized to a proventic source, the
    529  1.1.1.11  christos certificate should be re-generated.
    530       1.1  christos 
    531  1.1.1.11  christos   <p>Additional information on trusted groups and identity schemes is on the
    532  1.1.1.11  christos Autokey Public-Key Authentication
    533  1.1.1.11  christos page.
    534       1.1  christos 
    535  1.1.1.11  christos   <p>File names begin with the prefix
    536  1.1.1.11  christos <span class="file">ntpkey</span>_
    537  1.1.1.11  christos and end with the suffix
    538  1.1.1.11  christos <span class="file">_</span><kbd>hostname</kbd>. <kbd>filestamp</kbd>,
    539  1.1.1.11  christos where
    540  1.1.1.11  christos <kbd>hostname</kbd>
    541  1.1.1.11  christos is the owner name, usually the string returned
    542  1.1.1.11  christos by the Unix
    543  1.1.1.11  christos <code>hostname(1)</code>
    544  1.1.1.11  christos command, and
    545  1.1.1.11  christos <kbd>filestamp</kbd>
    546  1.1.1.11  christos is the NTP seconds when the file was generated, in decimal digits. 
    547  1.1.1.11  christos This both guarantees uniqueness and simplifies maintenance
    548  1.1.1.11  christos procedures, since all files can be quickly removed
    549  1.1.1.11  christos by a
    550  1.1.1.11  christos <code>rm</code> <span class="file">ntpkey*</span>
    551  1.1.1.11  christos command or all files generated
    552  1.1.1.11  christos at a specific time can be removed by a
    553  1.1.1.11  christos <code>rm</code> <span class="file">*</span><kbd>filestamp</kbd>
    554       1.1  christos command. 
    555  1.1.1.11  christos To further reduce the risk of misconfiguration,
    556  1.1.1.11  christos the first two lines of a file contain the file name
    557  1.1.1.11  christos and generation date and time as comments.
    558       1.1  christos 
    559  1.1.1.11  christos <h5 class="subsubsection">Trusted Hosts and Groups</h5>
    560       1.1  christos 
    561  1.1.1.11  christos <p>Each cryptographic configuration involves selection of a signature scheme
    562       1.1  christos and identification scheme, called a cryptotype,
    563       1.1  christos as explained in the
    564       1.1  christos <a href="#Authentication-Options">Authentication Options</a>
    565       1.1  christos section of
    566       1.1  christos <code>ntp.conf(5)</code>. 
    567  1.1.1.11  christos The default cryptotype uses
    568  1.1.1.11  christos <code>RSA</code>
    569  1.1.1.11  christos encryption,
    570  1.1.1.11  christos <code>MD5</code>
    571  1.1.1.11  christos message digest
    572  1.1.1.11  christos and
    573  1.1.1.11  christos <code>TC</code>
    574  1.1.1.11  christos identification. 
    575       1.1  christos First, configure a NTP subnet including one or more low-stratum
    576       1.1  christos trusted hosts from which all other hosts derive synchronization
    577       1.1  christos directly or indirectly. 
    578       1.1  christos Trusted hosts have trusted certificates;
    579       1.1  christos all other hosts have nontrusted certificates. 
    580       1.1  christos These hosts will automatically and dynamically build authoritative
    581       1.1  christos certificate trails to one or more trusted hosts. 
    582       1.1  christos A trusted group is the set of all hosts that have, directly or indirectly,
    583       1.1  christos a certificate trail ending at a trusted host. 
    584       1.1  christos The trail is defined by static configuration file entries
    585       1.1  christos or dynamic means described on the
    586       1.1  christos <a href="#Automatic-NTP-Configuration-Options">Automatic NTP Configuration Options</a>
    587       1.1  christos section of
    588       1.1  christos <code>ntp.conf(5)</code>.
    589       1.1  christos 
    590       1.1  christos   <p>On each trusted host as root, change to the keys directory. 
    591       1.1  christos To insure a fresh fileset, remove all
    592  1.1.1.11  christos <span class="file">ntpkey</span>
    593       1.1  christos files. 
    594       1.1  christos Then run
    595       1.1  christos <code>ntp-keygen</code>
    596       1.1  christos <code>-T</code>
    597       1.1  christos to generate keys and a trusted certificate. 
    598       1.1  christos On all other hosts do the same, but leave off the
    599       1.1  christos <code>-T</code>
    600       1.1  christos flag to generate keys and nontrusted certificates. 
    601       1.1  christos When complete, start the NTP daemons beginning at the lowest stratum
    602       1.1  christos and working up the tree. 
    603       1.1  christos It may take some time for Autokey to instantiate the certificate trails
    604       1.1  christos throughout the subnet, but setting up the environment is completely automatic.
    605       1.1  christos 
    606       1.1  christos   <p>If it is necessary to use a different sign key or different digest/signature
    607       1.1  christos scheme than the default, run
    608       1.1  christos <code>ntp-keygen</code>
    609       1.1  christos with the
    610       1.1  christos <code>-S</code> <kbd>type</kbd>
    611       1.1  christos option, where
    612       1.1  christos <kbd>type</kbd>
    613       1.1  christos is either
    614       1.1  christos <code>RSA</code>
    615       1.1  christos or
    616       1.1  christos <code>DSA</code>. 
    617  1.1.1.11  christos The most frequent need to do this is when a
    618  1.1.1.11  christos <code>DSA</code>-signed
    619  1.1.1.11  christos certificate is used. 
    620       1.1  christos If it is necessary to use a different certificate scheme than the default,
    621       1.1  christos run
    622       1.1  christos <code>ntp-keygen</code>
    623       1.1  christos with the
    624       1.1  christos <code>-c</code> <kbd>scheme</kbd>
    625       1.1  christos option and selected
    626       1.1  christos <kbd>scheme</kbd>
    627       1.1  christos as needed. 
    628  1.1.1.11  christos If
    629       1.1  christos <code>ntp-keygen</code>
    630       1.1  christos is run again without these options, it generates a new certificate
    631  1.1.1.11  christos using the same scheme and sign key, and soft link.
    632       1.1  christos 
    633       1.1  christos   <p>After setting up the environment it is advisable to update certificates
    634       1.1  christos from time to time, if only to extend the validity interval. 
    635       1.1  christos Simply run
    636       1.1  christos <code>ntp-keygen</code>
    637       1.1  christos with the same flags as before to generate new certificates
    638  1.1.1.11  christos using existing keys, and soft links. 
    639       1.1  christos However, if the host or sign key is changed,
    640       1.1  christos <code>ntpd(1ntpdmdoc)</code>
    641       1.1  christos should be restarted. 
    642       1.1  christos When
    643       1.1  christos <code>ntpd(1ntpdmdoc)</code>
    644       1.1  christos is restarted, it loads any new files and restarts the protocol. 
    645       1.1  christos Other dependent hosts will continue as usual until signatures are refreshed,
    646       1.1  christos at which time the protocol is restarted.
    647       1.1  christos 
    648       1.1  christos <h5 class="subsubsection">Identity Schemes</h5>
    649       1.1  christos 
    650       1.1  christos <p>As mentioned on the Autonomous Authentication page,
    651  1.1.1.11  christos the default
    652  1.1.1.11  christos <code>TC</code>
    653  1.1.1.11  christos identity scheme is vulnerable to a middleman attack. 
    654       1.1  christos However, there are more secure identity schemes available,
    655  1.1.1.11  christos including
    656  1.1.1.11  christos <code>PC</code>, <code>IFF</code>, <code>GQ</code>
    657  1.1.1.11  christos and
    658  1.1.1.11  christos <code>MV</code>
    659  1.1.1.11  christos schemes described below. 
    660       1.1  christos These schemes are based on a TA, one or more trusted hosts
    661       1.1  christos and some number of nontrusted hosts. 
    662       1.1  christos Trusted hosts prove identity using values provided by the TA,
    663       1.1  christos while the remaining hosts prove identity using values provided
    664       1.1  christos by a trusted host and certificate trails that end on that host. 
    665       1.1  christos The name of a trusted host is also the name of its sugroup
    666       1.1  christos and also the subject and issuer name on its trusted certificate. 
    667       1.1  christos The TA is not necessarily a trusted host in this sense, but often is.
    668       1.1  christos 
    669       1.1  christos   <p>In some schemes there are separate keys for servers and clients. 
    670       1.1  christos A server can also be a client of another server,
    671       1.1  christos but a client can never be a server for another client. 
    672       1.1  christos In general, trusted hosts and nontrusted hosts that operate
    673       1.1  christos as both server and client have parameter files that contain
    674       1.1  christos both server and client keys. 
    675       1.1  christos Hosts that operate
    676       1.1  christos only as clients have key files that contain only client keys.
    677       1.1  christos 
    678       1.1  christos   <p>The PC scheme supports only one trusted host in the group. 
    679       1.1  christos On trusted host alice run
    680       1.1  christos <code>ntp-keygen</code>
    681       1.1  christos <code>-P</code>
    682       1.1  christos <code>-p</code> <kbd>password</kbd>
    683       1.1  christos to generate the host key file
    684  1.1.1.11  christos <span class="file">ntpkey</span>_ <code>RSA</code> <span class="file">key_alice.</span> <kbd>filestamp</kbd>
    685       1.1  christos and trusted private certificate file
    686  1.1.1.11  christos <span class="file">ntpkey</span>_ <code>RSA-MD5</code> <code>_</code> <span class="file">cert_alice.</span> <kbd>filestamp</kbd>,
    687  1.1.1.11  christos and soft links. 
    688       1.1  christos Copy both files to all group hosts;
    689       1.1  christos they replace the files which would be generated in other schemes. 
    690  1.1.1.11  christos On each host
    691  1.1.1.11  christos <kbd>bob</kbd>
    692  1.1.1.11  christos install a soft link from the generic name
    693   1.1.1.7  christos <span class="file">ntpkey_host_</span><kbd>bob</kbd>
    694       1.1  christos to the host key file and soft link
    695   1.1.1.7  christos <span class="file">ntpkey_cert_</span><kbd>bob</kbd>
    696       1.1  christos to the private certificate file. 
    697       1.1  christos Note the generic links are on bob, but point to files generated
    698       1.1  christos by trusted host alice. 
    699       1.1  christos In this scheme it is not possible to refresh
    700       1.1  christos either the keys or certificates without copying them
    701  1.1.1.11  christos to all other hosts in the group, and recreating the soft links.
    702       1.1  christos 
    703  1.1.1.11  christos   <p>For the
    704  1.1.1.11  christos <code>IFF</code>
    705  1.1.1.11  christos scheme proceed as in the
    706  1.1.1.11  christos <code>TC</code>
    707  1.1.1.11  christos scheme to generate keys
    708       1.1  christos and certificates for all group hosts, then for every trusted host in the group,
    709  1.1.1.11  christos generate the
    710  1.1.1.11  christos <code>IFF</code>
    711  1.1.1.11  christos parameter file. 
    712       1.1  christos On trusted host alice run
    713       1.1  christos <code>ntp-keygen</code>
    714       1.1  christos <code>-T</code>
    715       1.1  christos <code>-I</code>
    716       1.1  christos <code>-p</code> <kbd>password</kbd>
    717       1.1  christos to produce her parameter file
    718  1.1.1.11  christos <span class="file">ntpkey_IFFpar_alice.</span><kbd>filestamp</kbd>,
    719       1.1  christos which includes both server and client keys. 
    720       1.1  christos Copy this file to all group hosts that operate as both servers
    721       1.1  christos and clients and install a soft link from the generic
    722  1.1.1.11  christos <span class="file">ntpkey_iff_alice</span>
    723       1.1  christos to this file. 
    724       1.1  christos If there are no hosts restricted to operate only as clients,
    725       1.1  christos there is nothing further to do. 
    726  1.1.1.11  christos As the
    727  1.1.1.11  christos <code>IFF</code>
    728  1.1.1.11  christos scheme is independent
    729       1.1  christos of keys and certificates, these files can be refreshed as needed.
    730       1.1  christos 
    731       1.1  christos   <p>If a rogue client has the parameter file, it could masquerade
    732       1.1  christos as a legitimate server and present a middleman threat. 
    733       1.1  christos To eliminate this threat, the client keys can be extracted
    734       1.1  christos from the parameter file and distributed to all restricted clients. 
    735       1.1  christos After generating the parameter file, on alice run
    736       1.1  christos <code>ntp-keygen</code>
    737       1.1  christos <code>-e</code>
    738  1.1.1.11  christos and pipe the output to a file or email program. 
    739  1.1.1.11  christos Copy or email this file to all restricted clients. 
    740       1.1  christos On these clients install a soft link from the generic
    741  1.1.1.11  christos <span class="file">ntpkey_iff_alice</span>
    742       1.1  christos to this file. 
    743       1.1  christos To further protect the integrity of the keys,
    744       1.1  christos each file can be encrypted with a secret password.
    745       1.1  christos 
    746  1.1.1.11  christos   <p>For the
    747  1.1.1.11  christos <code>GQ</code>
    748  1.1.1.11  christos scheme proceed as in the
    749  1.1.1.11  christos <code>TC</code>
    750  1.1.1.11  christos scheme to generate keys
    751       1.1  christos and certificates for all group hosts, then for every trusted host
    752  1.1.1.11  christos in the group, generate the
    753  1.1.1.11  christos <code>IFF</code>
    754  1.1.1.11  christos parameter file. 
    755       1.1  christos On trusted host alice run
    756       1.1  christos <code>ntp-keygen</code>
    757       1.1  christos <code>-T</code>
    758       1.1  christos <code>-G</code>
    759       1.1  christos <code>-p</code> <kbd>password</kbd>
    760       1.1  christos to produce her parameter file
    761  1.1.1.11  christos <span class="file">ntpkey_GQpar_alice.</span><kbd>filestamp</kbd>,
    762       1.1  christos which includes both server and client keys. 
    763       1.1  christos Copy this file to all group hosts and install a soft link
    764       1.1  christos from the generic
    765  1.1.1.11  christos <span class="file">ntpkey_gq_alice</span>
    766       1.1  christos to this file. 
    767  1.1.1.11  christos In addition, on each host
    768  1.1.1.11  christos <kbd>bob</kbd>
    769  1.1.1.11  christos install a soft link
    770       1.1  christos from generic
    771   1.1.1.7  christos <span class="file">ntpkey_gq_</span><kbd>bob</kbd>
    772       1.1  christos to this file. 
    773  1.1.1.11  christos As the
    774  1.1.1.11  christos <code>GQ</code>
    775  1.1.1.11  christos scheme updates the
    776  1.1.1.11  christos <code>GQ</code>
    777  1.1.1.11  christos parameters file and certificate
    778       1.1  christos at the same time, keys and certificates can be regenerated as needed.
    779       1.1  christos 
    780  1.1.1.11  christos   <p>For the
    781  1.1.1.11  christos <code>MV</code>
    782  1.1.1.11  christos scheme, proceed as in the
    783  1.1.1.11  christos <code>TC</code>
    784  1.1.1.11  christos scheme to generate keys
    785       1.1  christos and certificates for all group hosts. 
    786       1.1  christos For illustration assume trish is the TA, alice one of several trusted hosts
    787       1.1  christos and bob one of her clients. 
    788       1.1  christos On TA trish run
    789       1.1  christos <code>ntp-keygen</code>
    790       1.1  christos <code>-V</code> <kbd>n</kbd>
    791       1.1  christos <code>-p</code> <kbd>password</kbd>,
    792       1.1  christos where
    793       1.1  christos <kbd>n</kbd>
    794       1.1  christos is the number of revokable keys (typically 5) to produce
    795       1.1  christos the parameter file
    796  1.1.1.11  christos <span class="file">ntpkeys_MVpar_trish.</span><kbd>filestamp</kbd>
    797       1.1  christos and client key files
    798  1.1.1.11  christos <span class="file">ntpkeys_MVkey</span><kbd>d</kbd> <kbd>_</kbd> <span class="file">trish.</span> <kbd>filestamp</kbd>
    799       1.1  christos where
    800       1.1  christos <kbd>d</kbd>
    801       1.1  christos is the key number (0 &lt;
    802       1.1  christos <kbd>d</kbd>
    803       1.1  christos &lt;
    804       1.1  christos <kbd>n</kbd>). 
    805       1.1  christos Copy the parameter file to alice and install a soft link
    806       1.1  christos from the generic
    807  1.1.1.11  christos <span class="file">ntpkey_mv_alice</span>
    808       1.1  christos to this file. 
    809       1.1  christos Copy one of the client key files to alice for later distribution
    810       1.1  christos to her clients. 
    811  1.1.1.11  christos It does not matter which client key file goes to alice,
    812       1.1  christos since they all work the same way. 
    813  1.1.1.11  christos Alice copies the client key file to all of her clients. 
    814       1.1  christos On client bob install a soft link from generic
    815  1.1.1.11  christos <span class="file">ntpkey_mvkey_bob</span>
    816       1.1  christos to the client key file. 
    817  1.1.1.11  christos As the
    818  1.1.1.11  christos <code>MV</code>
    819  1.1.1.11  christos scheme is independent of keys and certificates,
    820       1.1  christos these files can be refreshed as needed.
    821       1.1  christos 
    822       1.1  christos <h5 class="subsubsection">Command Line Options</h5>
    823       1.1  christos 
    824       1.1  christos      <dl>
    825  1.1.1.11  christos <dt><code>-b</code> <code>--imbits</code>= <kbd>modulus</kbd><dd>Set the number of bits in the identity modulus for generating identity keys to
    826  1.1.1.11  christos <kbd>modulus</kbd>
    827  1.1.1.11  christos bits. 
    828  1.1.1.11  christos The number of bits in the identity modulus defaults to 256, but can be set to
    829  1.1.1.11  christos values from 256 to 2048 (32 to 256 octets). 
    830  1.1.1.11  christos Use the larger moduli with caution, as this can consume considerable computing
    831  1.1.1.11  christos resources and increases the size of authenticated packets. 
    832  1.1.1.11  christos <br><dt><code>-c</code> <code>--certificate</code>= <kbd>scheme</kbd><dd>Select certificate signature encryption/message digest scheme. 
    833       1.1  christos The
    834       1.1  christos <kbd>scheme</kbd>
    835       1.1  christos can be one of the following:
    836  1.1.1.11  christos <code>RSA-MD2</code>, <code>RSA-MD5</code>, <code>RSA-MDC2</code>, <code>RSA-SHA</code>, <code>RSA-SHA1</code>, <code>RSA-RIPEMD160</code>, <code>DSA-SHA</code>,
    837       1.1  christos or
    838       1.1  christos <code>DSA-SHA1</code>. 
    839  1.1.1.11  christos Note that
    840  1.1.1.11  christos <code>RSA</code>
    841  1.1.1.11  christos schemes must be used with an
    842  1.1.1.11  christos <code>RSA</code>
    843  1.1.1.11  christos sign key and
    844  1.1.1.11  christos <code>DSA</code>
    845  1.1.1.11  christos schemes must be used with a
    846  1.1.1.11  christos <code>DSA</code>
    847  1.1.1.11  christos sign key. 
    848       1.1  christos The default without this option is
    849       1.1  christos <code>RSA-MD5</code>. 
    850  1.1.1.11  christos If compatibility with FIPS 140-2 is required, either the
    851  1.1.1.11  christos <code>DSA-SHA</code>
    852  1.1.1.11  christos or
    853  1.1.1.11  christos <code>DSA-SHA1</code>
    854  1.1.1.11  christos scheme must be used. 
    855  1.1.1.11  christos <br><dt><code>-C</code> <code>--cipher</code>= <kbd>cipher</kbd><dd>Select the OpenSSL cipher to encrypt the files containing private keys. 
    856  1.1.1.11  christos The default without this option is three-key triple DES in CBC mode,
    857  1.1.1.11  christos <code>des-ede3-cbc</code>. 
    858  1.1.1.11  christos The
    859  1.1.1.11  christos <code>openssl</code> <code>-h</code>
    860  1.1.1.11  christos command provided with OpenSSL displays available ciphers. 
    861  1.1.1.11  christos <br><dt><code>-d</code> <code>--debug-level</code><dd>Increase debugging verbosity level. 
    862       1.1  christos This option displays the cryptographic data produced in eye-friendly billboards. 
    863  1.1.1.11  christos <br><dt><code>-D</code> <code>--set-debug-level</code>= <kbd>level</kbd><dd>Set the debugging verbosity to
    864  1.1.1.11  christos <kbd>level</kbd>. 
    865  1.1.1.11  christos This option displays the cryptographic data produced in eye-friendly billboards. 
    866  1.1.1.11  christos <br><dt><code>-e</code> <code>--id-key</code><dd>Write the
    867  1.1.1.11  christos <code>IFF</code>
    868  1.1.1.11  christos or
    869  1.1.1.11  christos <code>GQ</code>
    870  1.1.1.11  christos public parameters from the
    871  1.1.1.11  christos <kbd>IFFkey</kbd> <kbd>or</kbd> <kbd>GQkey</kbd>
    872  1.1.1.11  christos client keys file previously specified
    873  1.1.1.11  christos as unencrypted data to the standard output stream
    874  1.1.1.11  christos <span class="file">stdout</span>. 
    875  1.1.1.11  christos This is intended for automatic key distribution by email. 
    876  1.1.1.11  christos <br><dt><code>-G</code> <code>--gq-params</code><dd>Generate a new encrypted
    877  1.1.1.11  christos <code>GQ</code>
    878  1.1.1.11  christos parameters and key file for the Guillou-Quisquater (GQ) identity scheme. 
    879  1.1.1.11  christos This option is mutually exclusive with the
    880  1.1.1.11  christos <code>-I</code>
    881  1.1.1.11  christos and
    882  1.1.1.11  christos <code>-V</code>
    883  1.1.1.11  christos options. 
    884  1.1.1.11  christos <br><dt><code>-H</code> <code>--host-key</code><dd>Generate a new encrypted
    885  1.1.1.11  christos <code>RSA</code>
    886  1.1.1.11  christos public/private host key file. 
    887  1.1.1.11  christos <br><dt><code>-I</code> <code>--iffkey</code><dd>Generate a new encrypted
    888  1.1.1.11  christos <code>IFF</code>
    889  1.1.1.11  christos key file for the Schnorr (IFF) identity scheme. 
    890  1.1.1.11  christos This option is mutually exclusive with the
    891  1.1.1.11  christos <code>-G</code>
    892  1.1.1.11  christos and
    893  1.1.1.11  christos Fl V
    894  1.1.1.11  christos options. 
    895  1.1.1.11  christos <br><dt><code>-i</code> <code>--ident</code>= <kbd>group</kbd><dd>Set the optional Autokey group name to
    896  1.1.1.11  christos <kbd>group</kbd>. 
    897  1.1.1.11  christos This is used in the identity scheme parameter file names of
    898  1.1.1.11  christos <code>IFF</code>, <code>GQ</code>,
    899  1.1.1.11  christos and
    900  1.1.1.11  christos <code>MV</code>
    901  1.1.1.11  christos client parameters files. 
    902  1.1.1.11  christos In that role, the default is the host name if no group is provided. 
    903  1.1.1.11  christos The group name, if specified using
    904  1.1.1.11  christos <code>-i</code>
    905  1.1.1.11  christos or
    906  1.1.1.11  christos <code>-s</code>
    907  1.1.1.11  christos following an
    908  1.1.1.11  christos @
    909  1.1.1.11  christos character, is also used in certificate subject and issuer names in the form
    910  1.1.1.11  christos <kbd>host</kbd> <kbd>@</kbd> <kbd>group</kbd>
    911  1.1.1.11  christos and should match the group specified via
    912  1.1.1.11  christos <code>crypto</code> <code>ident</code>
    913  1.1.1.11  christos or
    914  1.1.1.11  christos <code>server</code> <code>ident</code>
    915  1.1.1.11  christos in the ntpd configuration file. 
    916  1.1.1.11  christos <br><dt><code>-l</code> <code>--lifetime</code>= <kbd>days</kbd><dd>Set the lifetime for certificate expiration to
    917  1.1.1.11  christos <kbd>days</kbd>. 
    918  1.1.1.11  christos The default lifetime is one year (365 days). 
    919  1.1.1.11  christos <br><dt><code>-m</code> <code>--modulus</code>= <kbd>bits</kbd><dd>Set the number of bits in the prime modulus for generating files to
    920  1.1.1.11  christos <kbd>bits</kbd>. 
    921  1.1.1.11  christos The modulus defaults to 512, but can be set from 256 to 2048 (32 to 256 octets). 
    922  1.1.1.11  christos Use the larger moduli with caution, as this can consume considerable computing
    923  1.1.1.11  christos resources and increases the size of authenticated packets. 
    924  1.1.1.11  christos <br><dt><code>-M</code> <code>--md5key</code><dd>Generate a new symmetric keys file containing 10
    925  1.1.1.11  christos <code>MD5</code>
    926  1.1.1.11  christos keys, and if OpenSSL is available, 10
    927  1.1.1.11  christos <code>SHA</code>
    928  1.1.1.11  christos keys. 
    929  1.1.1.11  christos An
    930  1.1.1.11  christos <code>MD5</code>
    931  1.1.1.11  christos key is a string of 20 random printable ASCII characters, while a
    932  1.1.1.11  christos <code>SHA</code>
    933  1.1.1.11  christos key is a string of 40 random hex digits. 
    934  1.1.1.11  christos The file can be edited using a text editor to change the key type or key content. 
    935  1.1.1.11  christos This option is mutually exclusive with all other options. 
    936  1.1.1.11  christos <br><dt><code>-p</code> <code>--password</code>= <kbd>passwd</kbd><dd>Set the password for reading and writing encrypted files to
    937  1.1.1.11  christos <kbd>passwd</kbd>. 
    938  1.1.1.11  christos These include the host, sign and identify key files. 
    939  1.1.1.11  christos By default, the password is the string returned by the Unix
    940  1.1.1.11  christos <code>hostname</code>
    941  1.1.1.11  christos command. 
    942  1.1.1.11  christos <br><dt><code>-P</code> <code>--pvt-cert</code><dd>Generate a new private certificate used by the
    943  1.1.1.11  christos <code>PC</code>
    944  1.1.1.11  christos identity scheme. 
    945       1.1  christos By default, the program generates public certificates. 
    946  1.1.1.11  christos Note: the PC identity scheme is not recommended for new installations. 
    947  1.1.1.11  christos <br><dt><code>-q</code> <code>--export-passwd</code>= <kbd>passwd</kbd><dd>Set the password for writing encrypted
    948  1.1.1.11  christos <code>IFF</code>, <code>GQ</code> <code>and</code> <code>MV</code>
    949  1.1.1.11  christos identity files redirected to
    950  1.1.1.11  christos <span class="file">stdout</span>
    951  1.1.1.11  christos to
    952  1.1.1.11  christos <kbd>passwd</kbd>. 
    953  1.1.1.11  christos In effect, these files are decrypted with the
    954  1.1.1.11  christos <code>-p</code>
    955  1.1.1.11  christos password, then encrypted with the
    956  1.1.1.11  christos <code>-q</code>
    957  1.1.1.11  christos password. 
    958  1.1.1.11  christos By default, the password is the string returned by the Unix
    959  1.1.1.11  christos <code>hostname</code>
    960  1.1.1.11  christos command. 
    961  1.1.1.11  christos <br><dt><code>-s</code> <code>--subject-key</code>= <code>[host]</code> <code>[@ </code><kbd>group</kbd><code>]</code><dd>Specify the Autokey host name, where
    962  1.1.1.11  christos <kbd>host</kbd>
    963  1.1.1.11  christos is the optional host name and
    964  1.1.1.11  christos <kbd>group</kbd>
    965  1.1.1.11  christos is the optional group name. 
    966  1.1.1.11  christos The host name, and if provided, group name are used in
    967  1.1.1.11  christos <kbd>host</kbd> <kbd>@</kbd> <kbd>group</kbd>
    968  1.1.1.11  christos form as certificate subject and issuer. 
    969  1.1.1.11  christos Specifying
    970  1.1.1.11  christos <code>-s</code> <code>-@</code> <kbd>group</kbd>
    971  1.1.1.11  christos is allowed, and results in leaving the host name unchanged, as with
    972  1.1.1.11  christos <code>-i</code> <kbd>group</kbd>. 
    973  1.1.1.11  christos The group name, or if no group is provided, the host name are also used in the
    974  1.1.1.11  christos file names of
    975  1.1.1.11  christos <code>IFF</code>, <code>GQ</code>,
    976  1.1.1.11  christos and
    977  1.1.1.11  christos <code>MV</code>
    978  1.1.1.11  christos identity scheme client parameter files. 
    979  1.1.1.11  christos If
    980  1.1.1.11  christos <kbd>host</kbd>
    981  1.1.1.11  christos is not specified, the default host name is the string returned by the Unix
    982  1.1.1.11  christos <code>hostname</code>
    983  1.1.1.11  christos command. 
    984  1.1.1.11  christos <br><dt><code>-S</code> <code>--sign-key</code>= <code>[RSA | DSA]</code><dd>Generate a new encrypted public/private sign key file of the specified type. 
    985  1.1.1.11  christos By default, the sign key is the host key and has the same type. 
    986  1.1.1.11  christos If compatibility with FIPS 140-2 is required, the sign key type must be
    987  1.1.1.11  christos <code>DSA</code>. 
    988  1.1.1.11  christos <br><dt><code>-T</code> <code>--trusted-cert</code><dd>Generate a trusted certificate. 
    989       1.1  christos By default, the program generates a non-trusted certificate. 
    990  1.1.1.11  christos <br><dt><code>-V</code> <code>--mv-params</code> <kbd>nkeys</kbd><dd>Generate
    991  1.1.1.11  christos <kbd>nkeys</kbd>
    992  1.1.1.11  christos encrypted server keys and parameters for the Mu-Varadharajan (MV)
    993  1.1.1.11  christos identity scheme. 
    994  1.1.1.11  christos This option is mutually exclusive with the
    995  1.1.1.11  christos <code>-I</code>
    996  1.1.1.11  christos and
    997  1.1.1.11  christos <code>-G</code>
    998  1.1.1.11  christos options. 
    999  1.1.1.11  christos Note: support for this option should be considered a work in progress. 
   1000       1.1  christos </dl>
   1001       1.1  christos 
   1002       1.1  christos <h5 class="subsubsection">Random Seed File</h5>
   1003       1.1  christos 
   1004       1.1  christos <p>All cryptographically sound key generation schemes must have means
   1005       1.1  christos to randomize the entropy seed used to initialize
   1006       1.1  christos the internal pseudo-random number generator used
   1007       1.1  christos by the library routines. 
   1008       1.1  christos The OpenSSL library uses a designated random seed file for this purpose. 
   1009       1.1  christos The file must be available when starting the NTP daemon and
   1010       1.1  christos <code>ntp-keygen</code>
   1011       1.1  christos program. 
   1012       1.1  christos If a site supports OpenSSL or its companion OpenSSH,
   1013       1.1  christos it is very likely that means to do this are already available.
   1014       1.1  christos 
   1015       1.1  christos   <p>It is important to understand that entropy must be evolved
   1016       1.1  christos for each generation, for otherwise the random number sequence
   1017       1.1  christos would be predictable. 
   1018       1.1  christos Various means dependent on external events, such as keystroke intervals,
   1019       1.1  christos can be used to do this and some systems have built-in entropy sources. 
   1020       1.1  christos Suitable means are described in the OpenSSL software documentation,
   1021       1.1  christos but are outside the scope of this page.
   1022       1.1  christos 
   1023       1.1  christos   <p>The entropy seed used by the OpenSSL library is contained in a file,
   1024       1.1  christos usually called
   1025  1.1.1.11  christos <span class="file">.rnd</span>,
   1026       1.1  christos which must be available when starting the NTP daemon
   1027       1.1  christos or the
   1028       1.1  christos <code>ntp-keygen</code>
   1029       1.1  christos program. 
   1030       1.1  christos The NTP daemon will first look for the file
   1031       1.1  christos using the path specified by the
   1032       1.1  christos <code>randfile</code>
   1033       1.1  christos subcommand of the
   1034       1.1  christos <code>crypto</code>
   1035       1.1  christos configuration command. 
   1036       1.1  christos If not specified in this way, or when starting the
   1037       1.1  christos <code>ntp-keygen</code>
   1038       1.1  christos program,
   1039       1.1  christos the OpenSSL library will look for the file using the path specified
   1040       1.1  christos by the
   1041       1.1  christos .Ev RANDFILE
   1042       1.1  christos environment variable in the user home directory,
   1043       1.1  christos whether root or some other user. 
   1044       1.1  christos If the
   1045       1.1  christos .Ev RANDFILE
   1046       1.1  christos environment variable is not present,
   1047       1.1  christos the library will look for the
   1048  1.1.1.11  christos <span class="file">.rnd</span>
   1049       1.1  christos file in the user home directory. 
   1050  1.1.1.11  christos Since both the
   1051  1.1.1.11  christos <code>ntp-keygen</code>
   1052  1.1.1.11  christos program and
   1053  1.1.1.11  christos <code>ntpd(1ntpdmdoc)</code>
   1054  1.1.1.11  christos daemon must run as root, the logical place to put this file is in
   1055  1.1.1.11  christos <span class="file">/.rnd</span>
   1056  1.1.1.11  christos or
   1057  1.1.1.11  christos <span class="file">/root/.rnd</span>. 
   1058       1.1  christos If the file is not available or cannot be written,
   1059       1.1  christos the daemon exits with a message to the system log and the program
   1060       1.1  christos exits with a suitable error message.
   1061       1.1  christos 
   1062       1.1  christos <h5 class="subsubsection">Cryptographic Data Files</h5>
   1063       1.1  christos 
   1064  1.1.1.11  christos <p>All file formats begin with two nonencrypted lines. 
   1065  1.1.1.11  christos The first line contains the file name, including the generated host name
   1066  1.1.1.11  christos and filestamp, in the format
   1067  1.1.1.11  christos <span class="file">ntpkey_</span><kbd>key</kbd> <kbd>_</kbd> <kbd>name</kbd>. <kbd>filestamp</kbd>,
   1068  1.1.1.11  christos where
   1069  1.1.1.11  christos <kbd>key</kbd>
   1070  1.1.1.11  christos is the key or parameter type,
   1071  1.1.1.11  christos <kbd>name</kbd>
   1072  1.1.1.11  christos is the host or group name and
   1073  1.1.1.11  christos <kbd>filestamp</kbd>
   1074  1.1.1.11  christos is the filestamp (NTP seconds) when the file was created. 
   1075  1.1.1.11  christos By convention,
   1076  1.1.1.11  christos <kbd>key</kbd>
   1077  1.1.1.11  christos names in generated file names include both upper and lower case
   1078  1.1.1.11  christos characters, while
   1079  1.1.1.11  christos <kbd>key</kbd>
   1080  1.1.1.11  christos names in generated link names include only lower case characters. 
   1081  1.1.1.11  christos The filestamp is not used in generated link names. 
   1082  1.1.1.11  christos The second line contains the datestamp in conventional Unix
   1083  1.1.1.11  christos <span class="file">date</span>
   1084  1.1.1.11  christos format. 
   1085  1.1.1.11  christos Lines beginning with
   1086  1.1.1.11  christos #
   1087  1.1.1.11  christos are considered comments and ignored by the
   1088       1.1  christos <code>ntp-keygen</code>
   1089       1.1  christos program and
   1090       1.1  christos <code>ntpd(1ntpdmdoc)</code>
   1091  1.1.1.11  christos daemon.
   1092  1.1.1.11  christos 
   1093  1.1.1.11  christos   <p>The remainder of the file contains cryptographic data, encoded first using ASN.1
   1094  1.1.1.11  christos rules, then encrypted if necessary, and finally written in PEM-encoded
   1095  1.1.1.11  christos printable ASCII text, preceded and followed by MIME content identifier lines.
   1096  1.1.1.11  christos 
   1097  1.1.1.11  christos   <p>The format of the symmetric keys file, ordinarily named
   1098  1.1.1.11  christos <span class="file">ntp.keys</span>,
   1099  1.1.1.11  christos is somewhat different than the other files in the interest of backward compatibility. 
   1100  1.1.1.11  christos Ordinarily, the file is generated by this program, but it can be constructed
   1101  1.1.1.11  christos and edited using an ordinary text editor.
   1102  1.1.1.11  christos <pre class="verbatim">
   1103  1.1.1.11  christos # ntpkey_MD5key_bk.ntp.org.3595864945
   1104  1.1.1.11  christos # Thu Dec 12 19:22:25 2013
   1105  1.1.1.11  christos 
   1106  1.1.1.11  christos 1  MD5 L";Nw&lt;\`.I&lt;f4U0)247"i  # MD5 key
   1107  1.1.1.11  christos 2  MD5 &amp;>l0%XXK9O'51VwV&lt;xq~  # MD5 key
   1108  1.1.1.11  christos 3  MD5 lb4zLW~d^!K:]RsD'qb6  # MD5 key
   1109  1.1.1.11  christos 4  MD5 Yue:tL[+vR)M\`n~bY,'?  # MD5 key
   1110  1.1.1.11  christos 5  MD5 B;fx'Kgr/&amp;4ZTbL6=RxA  # MD5 key
   1111  1.1.1.11  christos 6  MD5 4eYwa\`o@}3i@@@@V@@..R9!l  # MD5 key
   1112  1.1.1.11  christos 7  MD5 \`A.([h+;wTQ|xfi%Sn_!  # MD5 key
   1113  1.1.1.11  christos 8  MD5 45:V,r4]l6y^JH6"Sh?F  # MD5 key
   1114  1.1.1.11  christos 9  MD5 3-5vcn*6l29DS?Xdsg)*  # MD5 key
   1115  1.1.1.11  christos 10 MD5 2late4Me              # MD5 key
   1116  1.1.1.11  christos 11 SHA1 a27872d3030a9025b8446c751b4551a7629af65c  # SHA1 key
   1117  1.1.1.11  christos 12 SHA1 21bc3b4865dbb9e920902abdccb3e04ff97a5e74  # SHA1 key
   1118  1.1.1.11  christos 13 SHA1 2b7736fe24fef5ba85ae11594132ab5d6f6daba9  # SHA1 key
   1119  1.1.1.11  christos 14 SHA  a5332809c8878dd3a5b918819108a111509aeceb  # SHA  key
   1120  1.1.1.11  christos 15 MD2  2fe16c88c760ff2f16d4267e36c1aa6c926e6964  # MD2  key
   1121  1.1.1.11  christos 16 MD4  b2691811dc19cfc0e2f9bcacd74213f29812183d  # MD4  key
   1122  1.1.1.11  christos 17 MD5  e4d6735b8bdad58ec5ffcb087300a17f7fef1f7c  # MD5  key
   1123  1.1.1.11  christos 18 MDC2 a8d5e2315c025bf3a79174c87fbd10477de2eabc  # MDC2 key
   1124  1.1.1.11  christos 19 RIPEMD160 77ca332cafb30e3cafb174dcd5b80ded7ba9b3d2  # RIPEMD160 key
   1125  1.1.1.11  christos 20 AES128CMAC f92ff73eee86c1e7dc638d6489a04e4e555af878  # AES128CMAC key
   1126  1.1.1.11  christos </pre>
   1127  1.1.1.11  christos <pre class="example">     Figure 1. Typical Symmetric Key File
   1128  1.1.1.11  christos </pre>
   1129  1.1.1.11  christos   <p>Figure 1 shows a typical symmetric keys file used by the reference
   1130  1.1.1.11  christos implementation. 
   1131  1.1.1.11  christos Following the header the keys are entered one per line in the format
   1132       1.1  christos <pre class="example">     <kbd>keyno</kbd> <kbd>type</kbd> <kbd>key</kbd>
   1133       1.1  christos </pre>
   1134       1.1  christos   <p>where
   1135       1.1  christos <kbd>keyno</kbd>
   1136  1.1.1.12  christos is a positive integer in the range 1-65535;
   1137       1.1  christos <kbd>type</kbd>
   1138  1.1.1.11  christos is the key type for the message digest algorithm, which in the absence of the
   1139  1.1.1.11  christos OpenSSL library must be
   1140  1.1.1.11  christos <code>MD5</code>
   1141  1.1.1.11  christos to designate the MD5 message digest algorithm;
   1142  1.1.1.11  christos if the OpenSSL library is installed, the key type can be any
   1143  1.1.1.11  christos message digest algorithm supported by that library;
   1144  1.1.1.11  christos however, if compatibility with FIPS 140-2 is required,
   1145  1.1.1.11  christos the key type must be either
   1146  1.1.1.11  christos <code>SHA</code>
   1147  1.1.1.11  christos or
   1148  1.1.1.11  christos <code>SHA1</code>;
   1149       1.1  christos <kbd>key</kbd>
   1150       1.1  christos is the key itself,
   1151  1.1.1.11  christos which is a printable ASCII string 20 characters or less in length:
   1152  1.1.1.11  christos each character is chosen from the 93 printable characters
   1153  1.1.1.11  christos in the range 0x21 through 0x7e (
   1154  1.1.1.11  christos ! 
   1155  1.1.1.11  christos through
   1156  1.1.1.11  christos ~
   1157  1.1.1.11  christos ) excluding space and the
   1158  1.1.1.11  christos #
   1159  1.1.1.11  christos character, and terminated by whitespace or a
   1160       1.1  christos #
   1161  1.1.1.11  christos character. 
   1162  1.1.1.11  christos An OpenSSL key consists of a hex-encoded ASCII string of 40 characters, which
   1163  1.1.1.11  christos is truncated as necessary.
   1164       1.1  christos 
   1165       1.1  christos   <p>Note that the keys used by the
   1166       1.1  christos <code>ntpq(1ntpqmdoc)</code>
   1167       1.1  christos and
   1168       1.1  christos <code>ntpdc(1ntpdcmdoc)</code>
   1169       1.1  christos programs
   1170       1.1  christos are checked against passwords requested by the programs
   1171       1.1  christos and entered by hand, so it is generally appropriate to specify these keys
   1172       1.1  christos in human readable ASCII format.
   1173       1.1  christos 
   1174       1.1  christos   <p>The
   1175       1.1  christos <code>ntp-keygen</code>
   1176  1.1.1.11  christos program generates a symmetric keys file
   1177  1.1.1.11  christos <span class="file">ntpkey_MD5key_</span><kbd>hostname</kbd>. <kbd>filestamp</kbd>. 
   1178       1.1  christos Since the file contains private shared keys,
   1179       1.1  christos it should be visible only to root and distributed by secure means
   1180       1.1  christos to other subnet hosts. 
   1181       1.1  christos The NTP daemon loads the file
   1182   1.1.1.7  christos <span class="file">ntp.keys</span>,
   1183       1.1  christos so
   1184       1.1  christos <code>ntp-keygen</code>
   1185       1.1  christos installs a soft link from this name to the generated file. 
   1186       1.1  christos Subsequently, similar soft links must be installed by manual
   1187       1.1  christos or automated means on the other subnet hosts. 
   1188       1.1  christos While this file is not used with the Autokey Version 2 protocol,
   1189       1.1  christos it is needed to authenticate some remote configuration commands
   1190       1.1  christos used by the
   1191       1.1  christos <code>ntpq(1ntpqmdoc)</code>
   1192       1.1  christos and
   1193       1.1  christos <code>ntpdc(1ntpdcmdoc)</code>
   1194       1.1  christos utilities.
   1195       1.1  christos 
   1196       1.1  christos   <p>This section was generated by <strong>AutoGen</strong>,
   1197       1.1  christos using the <code>agtexi-cmd</code> template and the option descriptions for the <code>ntp-keygen</code> program. 
   1198       1.1  christos This software is released under the NTP license, &lt;http://ntp.org/license>;.
   1199       1.1  christos 
   1200       1.1  christos <ul class="menu">
   1201   1.1.1.7  christos <li><a accesskey="1" href="#ntp_002dkeygen-usage">ntp-keygen usage</a>:                   ntp-keygen help/usage (<span class="option">--help</span>)
   1202       1.1  christos <li><a accesskey="2" href="#ntp_002dkeygen-imbits">ntp-keygen imbits</a>:                  imbits option (-b)
   1203       1.1  christos <li><a accesskey="3" href="#ntp_002dkeygen-certificate">ntp-keygen certificate</a>:             certificate option (-c)
   1204       1.1  christos <li><a accesskey="4" href="#ntp_002dkeygen-cipher">ntp-keygen cipher</a>:                  cipher option (-C)
   1205       1.1  christos <li><a accesskey="5" href="#ntp_002dkeygen-id_002dkey">ntp-keygen id-key</a>:                  id-key option (-e)
   1206       1.1  christos <li><a accesskey="6" href="#ntp_002dkeygen-gq_002dparams">ntp-keygen gq-params</a>:               gq-params option (-G)
   1207       1.1  christos <li><a accesskey="7" href="#ntp_002dkeygen-host_002dkey">ntp-keygen host-key</a>:                host-key option (-H)
   1208       1.1  christos <li><a accesskey="8" href="#ntp_002dkeygen-iffkey">ntp-keygen iffkey</a>:                  iffkey option (-I)
   1209       1.1  christos <li><a accesskey="9" href="#ntp_002dkeygen-ident">ntp-keygen ident</a>:                   ident option (-i)
   1210       1.1  christos <li><a href="#ntp_002dkeygen-lifetime">ntp-keygen lifetime</a>:                lifetime option (-l)
   1211       1.1  christos <li><a href="#ntp_002dkeygen-modulus">ntp-keygen modulus</a>:                 modulus option (-m)
   1212  1.1.1.11  christos <li><a href="#ntp_002dkeygen-md5key">ntp-keygen md5key</a>:                  md5key option (-M)
   1213       1.1  christos <li><a href="#ntp_002dkeygen-pvt_002dcert">ntp-keygen pvt-cert</a>:                pvt-cert option (-P)
   1214   1.1.1.2  christos <li><a href="#ntp_002dkeygen-password">ntp-keygen password</a>:                password option (-p)
   1215   1.1.1.2  christos <li><a href="#ntp_002dkeygen-export_002dpasswd">ntp-keygen export-passwd</a>:           export-passwd option (-q)
   1216       1.1  christos <li><a href="#ntp_002dkeygen-subject_002dname">ntp-keygen subject-name</a>:            subject-name option (-s)
   1217  1.1.1.11  christos <li><a href="#ntp_002dkeygen-sign_002dkey">ntp-keygen sign-key</a>:                sign-key option (-S)
   1218       1.1  christos <li><a href="#ntp_002dkeygen-trusted_002dcert">ntp-keygen trusted-cert</a>:            trusted-cert option (-T)
   1219       1.1  christos <li><a href="#ntp_002dkeygen-mv_002dparams">ntp-keygen mv-params</a>:               mv-params option (-V)
   1220       1.1  christos <li><a href="#ntp_002dkeygen-mv_002dkeys">ntp-keygen mv-keys</a>:                 mv-keys option (-v)
   1221       1.1  christos <li><a href="#ntp_002dkeygen-config">ntp-keygen config</a>:                  presetting/configuring ntp-keygen
   1222       1.1  christos <li><a href="#ntp_002dkeygen-exit-status">ntp-keygen exit status</a>:             exit status
   1223       1.1  christos <li><a href="#ntp_002dkeygen-Usage">ntp-keygen Usage</a>:                   Usage
   1224       1.1  christos <li><a href="#ntp_002dkeygen-Notes">ntp-keygen Notes</a>:                   Notes
   1225       1.1  christos <li><a href="#ntp_002dkeygen-Bugs">ntp-keygen Bugs</a>:                    Bugs
   1226       1.1  christos </ul>
   1227       1.1  christos 
   1228       1.1  christos <div class="node">
   1229       1.1  christos <p><hr>
   1230   1.1.1.7  christos <a name="ntp_002dkeygen-usage"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntp_002dkeygen-imbits">ntp-keygen imbits</a>,
   1231       1.1  christos Up:&nbsp;<a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a>
   1232   1.1.1.7  christos <br>
   1233       1.1  christos </div>
   1234       1.1  christos 
   1235   1.1.1.7  christos <h4 class="subsection">ntp-keygen help/usage (<span class="option">--help</span>)</h4>
   1236       1.1  christos 
   1237       1.1  christos <p><a name="index-ntp_002dkeygen-help-3"></a>
   1238       1.1  christos This is the automatically generated usage text for ntp-keygen.
   1239       1.1  christos 
   1240       1.1  christos   <p>The text printed is the same whether selected with the <code>help</code> option
   1241   1.1.1.7  christos (<span class="option">--help</span>) or the <code>more-help</code> option (<span class="option">--more-help</span>).  <code>more-help</code> will print
   1242       1.1  christos the usage text by passing it through a pager program. 
   1243       1.1  christos <code>more-help</code> is disabled on platforms without a working
   1244       1.1  christos <code>fork(2)</code> function.  The <code>PAGER</code> environment variable is
   1245   1.1.1.7  christos used to select the program, defaulting to <span class="file">more</span>.  Both will exit
   1246       1.1  christos with a status code of 0.
   1247       1.1  christos 
   1248  1.1.1.12  christos <pre class="example">ntp-keygen (ntp) - Create a NTP host key - Ver. 4.2.8p11
   1249       1.1  christos Usage:  ntp-keygen [ -&lt;flag&gt; [&lt;val&gt;] | --&lt;name&gt;[{=| }&lt;val&gt;] ]...
   1250       1.1  christos   Flg Arg Option-Name    Description
   1251       1.1  christos    -b Num imbits         identity modulus bits
   1252       1.1  christos                                 - it must be in the range:
   1253       1.1  christos                                   256 to 2048
   1254       1.1  christos    -c Str certificate    certificate scheme
   1255       1.1  christos    -C Str cipher         privatekey cipher
   1256       1.1  christos    -d no  debug-level    Increase debug verbosity level
   1257       1.1  christos                                 - may appear multiple times
   1258       1.1  christos    -D Num set-debug-level Set the debug verbosity level
   1259       1.1  christos                                 - may appear multiple times
   1260       1.1  christos    -e no  id-key         Write IFF or GQ identity keys
   1261       1.1  christos    -G no  gq-params      Generate GQ parameters and keys
   1262       1.1  christos    -H no  host-key       generate RSA host key
   1263       1.1  christos    -I no  iffkey         generate IFF parameters
   1264       1.1  christos    -i Str ident          set Autokey group name
   1265       1.1  christos    -l Num lifetime       set certificate lifetime
   1266  1.1.1.11  christos    -m Num modulus        prime modulus
   1267       1.1  christos                                 - it must be in the range:
   1268       1.1  christos                                   256 to 2048
   1269  1.1.1.11  christos    -M no  md5key         generate symmetric keys
   1270       1.1  christos    -P no  pvt-cert       generate PC private certificate
   1271   1.1.1.2  christos    -p Str password       local private password
   1272   1.1.1.2  christos    -q Str export-passwd  export IFF or GQ group keys with password
   1273       1.1  christos    -s Str subject-name   set host and optionally group name
   1274  1.1.1.11  christos    -S Str sign-key       generate sign key (RSA or DSA)
   1275       1.1  christos    -T no  trusted-cert   trusted certificate (TC scheme)
   1276       1.1  christos    -V Num mv-params      generate &lt;num&gt; MV parameters
   1277       1.1  christos    -v Num mv-keys        update &lt;num&gt; MV keys
   1278       1.1  christos       opt version        output version information and exit
   1279       1.1  christos    -? no  help           display extended usage information and exit
   1280       1.1  christos    -! no  more-help      extended usage information passed thru pager
   1281       1.1  christos    -&gt; opt save-opts      save the option state to a config file
   1282       1.1  christos    -&lt; Str load-opts      load options from a config file
   1283       1.1  christos                                 - disabled as '--no-load-opts'
   1284       1.1  christos                                 - may appear multiple times
   1285       1.1  christos 
   1286       1.1  christos Options are specified by doubled hyphens and their name or by a single
   1287       1.1  christos hyphen and the flag character.
   1288       1.1  christos 
   1289       1.1  christos 
   1290       1.1  christos The following option preset mechanisms are supported:
   1291       1.1  christos  - reading file $HOME/.ntprc
   1292       1.1  christos  - reading file ./.ntprc
   1293       1.1  christos  - examining environment variables named NTP_KEYGEN_*
   1294       1.1  christos 
   1295       1.1  christos Please send bug reports to:  &lt;http://bugs.ntp.org, bugs (a] ntp.org&gt;
   1296       1.1  christos </pre>
   1297       1.1  christos   <div class="node">
   1298       1.1  christos <p><hr>
   1299   1.1.1.7  christos <a name="ntp_002dkeygen-imbits"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntp_002dkeygen-certificate">ntp-keygen certificate</a>,
   1300       1.1  christos Previous:&nbsp;<a rel="previous" accesskey="p" href="#ntp_002dkeygen-usage">ntp-keygen usage</a>,
   1301       1.1  christos Up:&nbsp;<a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a>
   1302   1.1.1.7  christos <br>
   1303       1.1  christos </div>
   1304       1.1  christos 
   1305       1.1  christos <h4 class="subsection">imbits option (-b)</h4>
   1306       1.1  christos 
   1307       1.1  christos <p><a name="index-ntp_002dkeygen_002dimbits-4"></a>
   1308       1.1  christos This is the &ldquo;identity modulus bits&rdquo; option. 
   1309   1.1.1.7  christos This option takes a number argument <span class="file">imbits</span>.
   1310       1.1  christos 
   1311       1.1  christos <p class="noindent">This option has some usage constraints.  It:
   1312       1.1  christos      <ul>
   1313       1.1  christos <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 
   1314       1.1  christos </ul>
   1315       1.1  christos 
   1316       1.1  christos   <p>The number of bits in the identity modulus.  The default is 256. 
   1317       1.1  christos <div class="node">
   1318       1.1  christos <p><hr>
   1319   1.1.1.7  christos <a name="ntp_002dkeygen-certificate"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntp_002dkeygen-cipher">ntp-keygen cipher</a>,
   1320       1.1  christos Previous:&nbsp;<a rel="previous" accesskey="p" href="#ntp_002dkeygen-imbits">ntp-keygen imbits</a>,
   1321       1.1  christos Up:&nbsp;<a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a>
   1322   1.1.1.7  christos <br>
   1323       1.1  christos </div>
   1324       1.1  christos 
   1325       1.1  christos <h4 class="subsection">certificate option (-c)</h4>
   1326       1.1  christos 
   1327       1.1  christos <p><a name="index-ntp_002dkeygen_002dcertificate-5"></a>
   1328       1.1  christos This is the &ldquo;certificate scheme&rdquo; option. 
   1329   1.1.1.7  christos This option takes a string argument <span class="file">scheme</span>.
   1330       1.1  christos 
   1331       1.1  christos <p class="noindent">This option has some usage constraints.  It:
   1332       1.1  christos      <ul>
   1333       1.1  christos <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 
   1334       1.1  christos </ul>
   1335       1.1  christos 
   1336       1.1  christos   <p>scheme is one of
   1337  1.1.1.11  christos RSA-MD2, RSA-MD5, RSA-MDC2, RSA-SHA, RSA-SHA1, RSA-RIPEMD160,
   1338       1.1  christos DSA-SHA, or DSA-SHA1.
   1339       1.1  christos 
   1340  1.1.1.11  christos   <p>Select the certificate signature encryption/message digest scheme. 
   1341       1.1  christos Note that RSA schemes must be used with a RSA sign key and DSA
   1342       1.1  christos schemes must be used with a DSA sign key.  The default without
   1343       1.1  christos this option is RSA-MD5. 
   1344       1.1  christos <div class="node">
   1345       1.1  christos <p><hr>
   1346   1.1.1.7  christos <a name="ntp_002dkeygen-cipher"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntp_002dkeygen-id_002dkey">ntp-keygen id-key</a>,
   1347       1.1  christos Previous:&nbsp;<a rel="previous" accesskey="p" href="#ntp_002dkeygen-certificate">ntp-keygen certificate</a>,
   1348       1.1  christos Up:&nbsp;<a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a>
   1349   1.1.1.7  christos <br>
   1350       1.1  christos </div>
   1351       1.1  christos 
   1352       1.1  christos <h4 class="subsection">cipher option (-C)</h4>
   1353       1.1  christos 
   1354       1.1  christos <p><a name="index-ntp_002dkeygen_002dcipher-6"></a>
   1355       1.1  christos This is the &ldquo;privatekey cipher&rdquo; option. 
   1356   1.1.1.7  christos This option takes a string argument <span class="file">cipher</span>.
   1357       1.1  christos 
   1358       1.1  christos <p class="noindent">This option has some usage constraints.  It:
   1359       1.1  christos      <ul>
   1360       1.1  christos <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 
   1361       1.1  christos </ul>
   1362       1.1  christos 
   1363       1.1  christos   <p>Select the cipher which is used to encrypt the files containing
   1364       1.1  christos private keys.  The default is three-key triple DES in CBC mode,
   1365  1.1.1.11  christos equivalent to "<code>-C des-ede3-cbc</code>".  The openssl tool lists ciphers
   1366  1.1.1.11  christos available in "<code>openssl -h</code>" output. 
   1367  1.1.1.11  christos <div class="node">
   1368       1.1  christos <p><hr>
   1369   1.1.1.7  christos <a name="ntp_002dkeygen-id_002dkey"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntp_002dkeygen-gq_002dparams">ntp-keygen gq-params</a>,
   1370       1.1  christos Previous:&nbsp;<a rel="previous" accesskey="p" href="#ntp_002dkeygen-cipher">ntp-keygen cipher</a>,
   1371       1.1  christos Up:&nbsp;<a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a>
   1372   1.1.1.7  christos <br>
   1373       1.1  christos </div>
   1374       1.1  christos 
   1375       1.1  christos <h4 class="subsection">id-key option (-e)</h4>
   1376       1.1  christos 
   1377       1.1  christos <p><a name="index-ntp_002dkeygen_002did_002dkey-7"></a>
   1378       1.1  christos This is the &ldquo;write iff or gq identity keys&rdquo; option.
   1379       1.1  christos 
   1380       1.1  christos <p class="noindent">This option has some usage constraints.  It:
   1381       1.1  christos      <ul>
   1382       1.1  christos <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 
   1383       1.1  christos </ul>
   1384       1.1  christos 
   1385  1.1.1.11  christos   <p>Write the public parameters from the IFF or GQ client keys to
   1386  1.1.1.11  christos the standard output. 
   1387  1.1.1.11  christos This is intended for automatic key distribution by email. 
   1388       1.1  christos <div class="node">
   1389       1.1  christos <p><hr>
   1390   1.1.1.7  christos <a name="ntp_002dkeygen-gq_002dparams"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntp_002dkeygen-host_002dkey">ntp-keygen host-key</a>,
   1391       1.1  christos Previous:&nbsp;<a rel="previous" accesskey="p" href="#ntp_002dkeygen-id_002dkey">ntp-keygen id-key</a>,
   1392       1.1  christos Up:&nbsp;<a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a>
   1393   1.1.1.7  christos <br>
   1394       1.1  christos </div>
   1395       1.1  christos 
   1396       1.1  christos <h4 class="subsection">gq-params option (-G)</h4>
   1397       1.1  christos 
   1398       1.1  christos <p><a name="index-ntp_002dkeygen_002dgq_002dparams-8"></a>
   1399       1.1  christos This is the &ldquo;generate gq parameters and keys&rdquo; option.
   1400       1.1  christos 
   1401       1.1  christos <p class="noindent">This option has some usage constraints.  It:
   1402       1.1  christos      <ul>
   1403       1.1  christos <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 
   1404       1.1  christos </ul>
   1405       1.1  christos 
   1406       1.1  christos   <p>Generate parameters and keys for the GQ identification scheme,
   1407       1.1  christos obsoleting any that may exist. 
   1408       1.1  christos <div class="node">
   1409       1.1  christos <p><hr>
   1410   1.1.1.7  christos <a name="ntp_002dkeygen-host_002dkey"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntp_002dkeygen-iffkey">ntp-keygen iffkey</a>,
   1411       1.1  christos Previous:&nbsp;<a rel="previous" accesskey="p" href="#ntp_002dkeygen-gq_002dparams">ntp-keygen gq-params</a>,
   1412       1.1  christos Up:&nbsp;<a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a>
   1413   1.1.1.7  christos <br>
   1414       1.1  christos </div>
   1415       1.1  christos 
   1416       1.1  christos <h4 class="subsection">host-key option (-H)</h4>
   1417       1.1  christos 
   1418       1.1  christos <p><a name="index-ntp_002dkeygen_002dhost_002dkey-9"></a>
   1419       1.1  christos This is the &ldquo;generate rsa host key&rdquo; option.
   1420       1.1  christos 
   1421       1.1  christos <p class="noindent">This option has some usage constraints.  It:
   1422       1.1  christos      <ul>
   1423       1.1  christos <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 
   1424       1.1  christos </ul>
   1425       1.1  christos 
   1426       1.1  christos   <p>Generate new host keys, obsoleting any that may exist. 
   1427       1.1  christos <div class="node">
   1428       1.1  christos <p><hr>
   1429   1.1.1.7  christos <a name="ntp_002dkeygen-iffkey"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntp_002dkeygen-ident">ntp-keygen ident</a>,
   1430       1.1  christos Previous:&nbsp;<a rel="previous" accesskey="p" href="#ntp_002dkeygen-host_002dkey">ntp-keygen host-key</a>,
   1431       1.1  christos Up:&nbsp;<a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a>
   1432   1.1.1.7  christos <br>
   1433       1.1  christos </div>
   1434       1.1  christos 
   1435       1.1  christos <h4 class="subsection">iffkey option (-I)</h4>
   1436       1.1  christos 
   1437       1.1  christos <p><a name="index-ntp_002dkeygen_002diffkey-10"></a>
   1438       1.1  christos This is the &ldquo;generate iff parameters&rdquo; option.
   1439       1.1  christos 
   1440       1.1  christos <p class="noindent">This option has some usage constraints.  It:
   1441       1.1  christos      <ul>
   1442       1.1  christos <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 
   1443       1.1  christos </ul>
   1444       1.1  christos 
   1445       1.1  christos   <p>Generate parameters for the IFF identification scheme, obsoleting
   1446       1.1  christos any that may exist. 
   1447       1.1  christos <div class="node">
   1448       1.1  christos <p><hr>
   1449   1.1.1.7  christos <a name="ntp_002dkeygen-ident"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntp_002dkeygen-lifetime">ntp-keygen lifetime</a>,
   1450       1.1  christos Previous:&nbsp;<a rel="previous" accesskey="p" href="#ntp_002dkeygen-iffkey">ntp-keygen iffkey</a>,
   1451       1.1  christos Up:&nbsp;<a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a>
   1452   1.1.1.7  christos <br>
   1453       1.1  christos </div>
   1454       1.1  christos 
   1455       1.1  christos <h4 class="subsection">ident option (-i)</h4>
   1456       1.1  christos 
   1457       1.1  christos <p><a name="index-ntp_002dkeygen_002dident-11"></a>
   1458       1.1  christos This is the &ldquo;set autokey group name&rdquo; option. 
   1459   1.1.1.7  christos This option takes a string argument <span class="file">group</span>.
   1460       1.1  christos 
   1461       1.1  christos <p class="noindent">This option has some usage constraints.  It:
   1462       1.1  christos      <ul>
   1463       1.1  christos <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 
   1464       1.1  christos </ul>
   1465       1.1  christos 
   1466       1.1  christos   <p>Set the optional Autokey group name to name.  This is used in
   1467       1.1  christos the file name of IFF, GQ, and MV client parameters files.  In
   1468       1.1  christos that role, the default is the host name if this option is not
   1469       1.1  christos provided.  The group name, if specified using <code>-i/--ident</code> or
   1470  1.1.1.11  christos using <code>-s/--subject-name</code> following an '<code>@</code>' character,
   1471  1.1.1.11  christos is also a part of the self-signed host certificate subject and
   1472  1.1.1.11  christos issuer names in the form <code>host@group</code> and should match the
   1473  1.1.1.11  christos '<code>crypto ident</code>' or '<code>server ident</code>' configuration in the
   1474  1.1.1.11  christos <code>ntpd</code> configuration file. 
   1475  1.1.1.11  christos <div class="node">
   1476       1.1  christos <p><hr>
   1477  1.1.1.11  christos <a name="ntp_002dkeygen-lifetime"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntp_002dkeygen-modulus">ntp-keygen modulus</a>,
   1478       1.1  christos Previous:&nbsp;<a rel="previous" accesskey="p" href="#ntp_002dkeygen-ident">ntp-keygen ident</a>,
   1479       1.1  christos Up:&nbsp;<a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a>
   1480   1.1.1.7  christos <br>
   1481       1.1  christos </div>
   1482       1.1  christos 
   1483       1.1  christos <h4 class="subsection">lifetime option (-l)</h4>
   1484       1.1  christos 
   1485       1.1  christos <p><a name="index-ntp_002dkeygen_002dlifetime-12"></a>
   1486  1.1.1.11  christos This is the &ldquo;set certificate lifetime&rdquo; option. 
   1487   1.1.1.7  christos This option takes a number argument <span class="file">lifetime</span>.
   1488       1.1  christos 
   1489       1.1  christos <p class="noindent">This option has some usage constraints.  It:
   1490       1.1  christos      <ul>
   1491       1.1  christos <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 
   1492       1.1  christos </ul>
   1493       1.1  christos 
   1494       1.1  christos   <p>Set the certificate expiration to lifetime days from now. 
   1495       1.1  christos <div class="node">
   1496       1.1  christos <p><hr>
   1497  1.1.1.11  christos <a name="ntp_002dkeygen-modulus"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntp_002dkeygen-md5key">ntp-keygen md5key</a>,
   1498       1.1  christos Previous:&nbsp;<a rel="previous" accesskey="p" href="#ntp_002dkeygen-lifetime">ntp-keygen lifetime</a>,
   1499       1.1  christos Up:&nbsp;<a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a>
   1500   1.1.1.7  christos <br>
   1501       1.1  christos </div>
   1502       1.1  christos 
   1503       1.1  christos <h4 class="subsection">modulus option (-m)</h4>
   1504       1.1  christos 
   1505  1.1.1.11  christos <p><a name="index-ntp_002dkeygen_002dmodulus-13"></a>
   1506  1.1.1.11  christos This is the &ldquo;prime modulus&rdquo; option. 
   1507   1.1.1.7  christos This option takes a number argument <span class="file">modulus</span>.
   1508       1.1  christos 
   1509       1.1  christos <p class="noindent">This option has some usage constraints.  It:
   1510       1.1  christos      <ul>
   1511       1.1  christos <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 
   1512       1.1  christos </ul>
   1513       1.1  christos 
   1514       1.1  christos   <p>The number of bits in the prime modulus.  The default is 512. 
   1515       1.1  christos <div class="node">
   1516       1.1  christos <p><hr>
   1517  1.1.1.11  christos <a name="ntp_002dkeygen-md5key"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntp_002dkeygen-pvt_002dcert">ntp-keygen pvt-cert</a>,
   1518       1.1  christos Previous:&nbsp;<a rel="previous" accesskey="p" href="#ntp_002dkeygen-modulus">ntp-keygen modulus</a>,
   1519       1.1  christos Up:&nbsp;<a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a>
   1520   1.1.1.7  christos <br>
   1521       1.1  christos </div>
   1522       1.1  christos 
   1523  1.1.1.11  christos <h4 class="subsection">md5key option (-M)</h4>
   1524  1.1.1.11  christos 
   1525  1.1.1.11  christos <p><a name="index-ntp_002dkeygen_002dmd5key-14"></a>
   1526  1.1.1.11  christos This is the &ldquo;generate symmetric keys&rdquo; option. 
   1527  1.1.1.11  christos Generate symmetric keys, obsoleting any that may exist. 
   1528  1.1.1.11  christos <div class="node">
   1529  1.1.1.11  christos <p><hr>
   1530  1.1.1.11  christos <a name="ntp_002dkeygen-pvt_002dcert"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntp_002dkeygen-password">ntp-keygen password</a>,
   1531  1.1.1.11  christos Previous:&nbsp;<a rel="previous" accesskey="p" href="#ntp_002dkeygen-md5key">ntp-keygen md5key</a>,
   1532  1.1.1.11  christos Up:&nbsp;<a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a>
   1533  1.1.1.11  christos <br>
   1534  1.1.1.11  christos </div>
   1535  1.1.1.11  christos 
   1536       1.1  christos <h4 class="subsection">pvt-cert option (-P)</h4>
   1537       1.1  christos 
   1538       1.1  christos <p><a name="index-ntp_002dkeygen_002dpvt_002dcert-15"></a>
   1539  1.1.1.11  christos This is the &ldquo;generate pc private certificate&rdquo; option.
   1540       1.1  christos 
   1541       1.1  christos <p class="noindent">This option has some usage constraints.  It:
   1542       1.1  christos      <ul>
   1543       1.1  christos <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 
   1544       1.1  christos </ul>
   1545       1.1  christos 
   1546       1.1  christos   <p>Generate a private certificate.  By default, the program generates
   1547       1.1  christos public certificates. 
   1548       1.1  christos <div class="node">
   1549       1.1  christos <p><hr>
   1550   1.1.1.7  christos <a name="ntp_002dkeygen-password"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntp_002dkeygen-export_002dpasswd">ntp-keygen export-passwd</a>,
   1551       1.1  christos Previous:&nbsp;<a rel="previous" accesskey="p" href="#ntp_002dkeygen-pvt_002dcert">ntp-keygen pvt-cert</a>,
   1552       1.1  christos Up:&nbsp;<a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a>
   1553   1.1.1.7  christos <br>
   1554       1.1  christos </div>
   1555       1.1  christos 
   1556   1.1.1.2  christos <h4 class="subsection">password option (-p)</h4>
   1557       1.1  christos 
   1558   1.1.1.2  christos <p><a name="index-ntp_002dkeygen_002dpassword-16"></a>
   1559  1.1.1.11  christos This is the &ldquo;local private password&rdquo; option. 
   1560   1.1.1.7  christos This option takes a string argument <span class="file">passwd</span>.
   1561       1.1  christos 
   1562       1.1  christos <p class="noindent">This option has some usage constraints.  It:
   1563       1.1  christos      <ul>
   1564       1.1  christos <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 
   1565       1.1  christos </ul>
   1566       1.1  christos 
   1567   1.1.1.2  christos   <p>Local files containing private data are encrypted with the
   1568   1.1.1.2  christos DES-CBC algorithm and the specified password.  The same password
   1569   1.1.1.2  christos must be specified to the local ntpd via the "crypto pw password"
   1570   1.1.1.2  christos configuration command.  The default password is the local
   1571   1.1.1.2  christos hostname. 
   1572       1.1  christos <div class="node">
   1573       1.1  christos <p><hr>
   1574  1.1.1.11  christos <a name="ntp_002dkeygen-export_002dpasswd"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntp_002dkeygen-subject_002dname">ntp-keygen subject-name</a>,
   1575   1.1.1.2  christos Previous:&nbsp;<a rel="previous" accesskey="p" href="#ntp_002dkeygen-password">ntp-keygen password</a>,
   1576       1.1  christos Up:&nbsp;<a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a>
   1577   1.1.1.7  christos <br>
   1578       1.1  christos </div>
   1579       1.1  christos 
   1580   1.1.1.2  christos <h4 class="subsection">export-passwd option (-q)</h4>
   1581       1.1  christos 
   1582   1.1.1.2  christos <p><a name="index-ntp_002dkeygen_002dexport_002dpasswd-17"></a>
   1583  1.1.1.11  christos This is the &ldquo;export iff or gq group keys with password&rdquo; option. 
   1584   1.1.1.7  christos This option takes a string argument <span class="file">passwd</span>.
   1585       1.1  christos 
   1586       1.1  christos <p class="noindent">This option has some usage constraints.  It:
   1587       1.1  christos      <ul>
   1588       1.1  christos <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 
   1589       1.1  christos </ul>
   1590       1.1  christos 
   1591   1.1.1.2  christos   <p>Export IFF or GQ identity group keys to the standard output,
   1592   1.1.1.2  christos encrypted with the DES-CBC algorithm and the specified password. 
   1593   1.1.1.2  christos The same password must be specified to the remote ntpd via the
   1594   1.1.1.2  christos "crypto pw password" configuration command.  See also the option
   1595  1.1.1.11  christos &ndash;id-key (-e) for unencrypted exports. 
   1596       1.1  christos <div class="node">
   1597       1.1  christos <p><hr>
   1598  1.1.1.11  christos <a name="ntp_002dkeygen-subject_002dname"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntp_002dkeygen-sign_002dkey">ntp-keygen sign-key</a>,
   1599   1.1.1.2  christos Previous:&nbsp;<a rel="previous" accesskey="p" href="#ntp_002dkeygen-export_002dpasswd">ntp-keygen export-passwd</a>,
   1600       1.1  christos Up:&nbsp;<a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a>
   1601   1.1.1.7  christos <br>
   1602       1.1  christos </div>
   1603       1.1  christos 
   1604  1.1.1.11  christos <h4 class="subsection">subject-name option (-s)</h4>
   1605       1.1  christos 
   1606  1.1.1.11  christos <p><a name="index-ntp_002dkeygen_002dsubject_002dname-18"></a>
   1607  1.1.1.11  christos This is the &ldquo;set host and optionally group name&rdquo; option. 
   1608  1.1.1.11  christos This option takes a string argument <span class="file">host@group</span>.
   1609       1.1  christos 
   1610       1.1  christos <p class="noindent">This option has some usage constraints.  It:
   1611       1.1  christos      <ul>
   1612       1.1  christos <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 
   1613       1.1  christos </ul>
   1614       1.1  christos 
   1615  1.1.1.11  christos   <p>Set the Autokey host name, and optionally, group name specified
   1616  1.1.1.11  christos following an '<code>@</code>' character.  The host name is used in the file
   1617  1.1.1.11  christos name of generated host and signing certificates, without the
   1618  1.1.1.11  christos group name.  The host name, and if provided, group name are used
   1619  1.1.1.11  christos in <code>host@group</code> form for the host certificate subject and issuer
   1620  1.1.1.11  christos fields.  Specifying '<code>-s @group</code>' is allowed, and results in
   1621  1.1.1.11  christos leaving the host name unchanged while appending <code>@group</code> to the
   1622  1.1.1.11  christos subject and issuer fields, as with <code>-i group</code>.  The group name, or
   1623  1.1.1.11  christos if not provided, the host name are also used in the file names
   1624  1.1.1.11  christos of IFF, GQ, and MV client parameter files. 
   1625       1.1  christos <div class="node">
   1626       1.1  christos <p><hr>
   1627  1.1.1.11  christos <a name="ntp_002dkeygen-sign_002dkey"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntp_002dkeygen-trusted_002dcert">ntp-keygen trusted-cert</a>,
   1628  1.1.1.11  christos Previous:&nbsp;<a rel="previous" accesskey="p" href="#ntp_002dkeygen-subject_002dname">ntp-keygen subject-name</a>,
   1629       1.1  christos Up:&nbsp;<a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a>
   1630   1.1.1.7  christos <br>
   1631       1.1  christos </div>
   1632       1.1  christos 
   1633  1.1.1.11  christos <h4 class="subsection">sign-key option (-S)</h4>
   1634       1.1  christos 
   1635  1.1.1.11  christos <p><a name="index-ntp_002dkeygen_002dsign_002dkey-19"></a>
   1636  1.1.1.11  christos This is the &ldquo;generate sign key (rsa or dsa)&rdquo; option. 
   1637  1.1.1.11  christos This option takes a string argument <span class="file">sign</span>.
   1638       1.1  christos 
   1639       1.1  christos <p class="noindent">This option has some usage constraints.  It:
   1640       1.1  christos      <ul>
   1641       1.1  christos <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 
   1642       1.1  christos </ul>
   1643       1.1  christos 
   1644  1.1.1.11  christos   <p>Generate a new sign key of the designated type, obsoleting any
   1645  1.1.1.11  christos that may exist.  By default, the program uses the host key as the
   1646  1.1.1.11  christos sign key. 
   1647  1.1.1.11  christos <div class="node">
   1648       1.1  christos <p><hr>
   1649   1.1.1.7  christos <a name="ntp_002dkeygen-trusted_002dcert"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntp_002dkeygen-mv_002dparams">ntp-keygen mv-params</a>,
   1650  1.1.1.11  christos Previous:&nbsp;<a rel="previous" accesskey="p" href="#ntp_002dkeygen-sign_002dkey">ntp-keygen sign-key</a>,
   1651       1.1  christos Up:&nbsp;<a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a>
   1652   1.1.1.7  christos <br>
   1653       1.1  christos </div>
   1654       1.1  christos 
   1655       1.1  christos <h4 class="subsection">trusted-cert option (-T)</h4>
   1656       1.1  christos 
   1657       1.1  christos <p><a name="index-ntp_002dkeygen_002dtrusted_002dcert-20"></a>
   1658  1.1.1.11  christos This is the &ldquo;trusted certificate (tc scheme)&rdquo; option.
   1659       1.1  christos 
   1660       1.1  christos <p class="noindent">This option has some usage constraints.  It:
   1661       1.1  christos      <ul>
   1662       1.1  christos <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 
   1663       1.1  christos </ul>
   1664       1.1  christos 
   1665       1.1  christos   <p>Generate a trusted certificate.  By default, the program generates
   1666       1.1  christos a non-trusted certificate. 
   1667       1.1  christos <div class="node">
   1668       1.1  christos <p><hr>
   1669   1.1.1.7  christos <a name="ntp_002dkeygen-mv_002dparams"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntp_002dkeygen-mv_002dkeys">ntp-keygen mv-keys</a>,
   1670       1.1  christos Previous:&nbsp;<a rel="previous" accesskey="p" href="#ntp_002dkeygen-trusted_002dcert">ntp-keygen trusted-cert</a>,
   1671       1.1  christos Up:&nbsp;<a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a>
   1672   1.1.1.7  christos <br>
   1673       1.1  christos </div>
   1674       1.1  christos 
   1675       1.1  christos <h4 class="subsection">mv-params option (-V)</h4>
   1676       1.1  christos 
   1677       1.1  christos <p><a name="index-ntp_002dkeygen_002dmv_002dparams-21"></a>
   1678  1.1.1.11  christos This is the &ldquo;generate &lt;num&gt; mv parameters&rdquo; option. 
   1679   1.1.1.7  christos This option takes a number argument <span class="file">num</span>.
   1680       1.1  christos 
   1681       1.1  christos <p class="noindent">This option has some usage constraints.  It:
   1682       1.1  christos      <ul>
   1683       1.1  christos <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 
   1684       1.1  christos </ul>
   1685       1.1  christos 
   1686       1.1  christos   <p>Generate parameters and keys for the Mu-Varadharajan (MV)
   1687       1.1  christos identification scheme. 
   1688       1.1  christos <div class="node">
   1689       1.1  christos <p><hr>
   1690   1.1.1.7  christos <a name="ntp_002dkeygen-mv_002dkeys"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntp_002dkeygen-config">ntp-keygen config</a>,
   1691       1.1  christos Previous:&nbsp;<a rel="previous" accesskey="p" href="#ntp_002dkeygen-mv_002dparams">ntp-keygen mv-params</a>,
   1692       1.1  christos Up:&nbsp;<a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a>
   1693   1.1.1.7  christos <br>
   1694       1.1  christos </div>
   1695       1.1  christos 
   1696       1.1  christos <h4 class="subsection">mv-keys option (-v)</h4>
   1697       1.1  christos 
   1698       1.1  christos <p><a name="index-ntp_002dkeygen_002dmv_002dkeys-22"></a>
   1699  1.1.1.11  christos This is the &ldquo;update &lt;num&gt; mv keys&rdquo; option. 
   1700   1.1.1.7  christos This option takes a number argument <span class="file">num</span>.
   1701       1.1  christos 
   1702       1.1  christos <p class="noindent">This option has some usage constraints.  It:
   1703       1.1  christos      <ul>
   1704       1.1  christos <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 
   1705       1.1  christos </ul>
   1706       1.1  christos 
   1707   1.1.1.7  christos   <p>This option has no <span class="samp">doc</span> documentation.
   1708       1.1  christos 
   1709       1.1  christos <div class="node">
   1710       1.1  christos <p><hr>
   1711   1.1.1.7  christos <a name="ntp_002dkeygen-config"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntp_002dkeygen-exit-status">ntp-keygen exit status</a>,
   1712       1.1  christos Previous:&nbsp;<a rel="previous" accesskey="p" href="#ntp_002dkeygen-mv_002dkeys">ntp-keygen mv-keys</a>,
   1713       1.1  christos Up:&nbsp;<a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a>
   1714   1.1.1.7  christos <br>
   1715       1.1  christos </div>
   1716       1.1  christos 
   1717       1.1  christos <h4 class="subsection">presetting/configuring ntp-keygen</h4>
   1718       1.1  christos 
   1719       1.1  christos <p>Any option that is not marked as <i>not presettable</i> may be preset by
   1720       1.1  christos loading values from configuration ("rc" or "ini") files, and values from environment variables named <code>NTP-KEYGEN</code> and <code>NTP-KEYGEN_&lt;OPTION_NAME&gt;</code>.  <code>&lt;OPTION_NAME&gt;</code> must be one of
   1721       1.1  christos the options listed above in upper case and segmented with underscores. 
   1722       1.1  christos The <code>NTP-KEYGEN</code> variable will be tokenized and parsed like
   1723       1.1  christos the command line.  The remaining variables are tested for existence and their
   1724       1.1  christos values are treated like option arguments.
   1725       1.1  christos 
   1726       1.1  christos <p class="noindent"><code>libopts</code> will search in 2 places for configuration files:
   1727       1.1  christos      <ul>
   1728       1.1  christos <li>$HOME
   1729       1.1  christos <li>$PWD
   1730       1.1  christos </ul>
   1731       1.1  christos   The environment variables <code>HOME</code>, and <code>PWD</code>
   1732   1.1.1.7  christos are expanded and replaced when <span class="file">ntp-keygen</span> runs. 
   1733       1.1  christos For any of these that are plain files, they are simply processed. 
   1734   1.1.1.7  christos For any that are directories, then a file named <span class="file">.ntprc</span> is searched for
   1735       1.1  christos within that directory and processed.
   1736       1.1  christos 
   1737       1.1  christos   <p>Configuration files may be in a wide variety of formats. 
   1738       1.1  christos The basic format is an option name followed by a value (argument) on the
   1739       1.1  christos same line.  Values may be separated from the option name with a colon,
   1740       1.1  christos equal sign or simply white space.  Values may be continued across multiple
   1741       1.1  christos lines by escaping the newline with a backslash.
   1742       1.1  christos 
   1743       1.1  christos   <p>Multiple programs may also share the same initialization file. 
   1744       1.1  christos Common options are collected at the top, followed by program specific
   1745       1.1  christos segments.  The segments are separated by lines like:
   1746       1.1  christos <pre class="example">    [NTP-KEYGEN]
   1747       1.1  christos </pre>
   1748       1.1  christos   <p class="noindent">or by
   1749       1.1  christos <pre class="example">    &lt;?program ntp-keygen&gt;
   1750       1.1  christos </pre>
   1751       1.1  christos   <p class="noindent">Do not mix these styles within one configuration file.
   1752       1.1  christos 
   1753       1.1  christos   <p>Compound values and carefully constructed string values may also be
   1754       1.1  christos specified using XML syntax:
   1755       1.1  christos <pre class="example">    &lt;option-name&gt;
   1756       1.1  christos        &lt;sub-opt&gt;...&amp;lt;...&amp;gt;...&lt;/sub-opt&gt;
   1757       1.1  christos     &lt;/option-name&gt;
   1758       1.1  christos </pre>
   1759       1.1  christos   <p class="noindent">yielding an <code>option-name.sub-opt</code> string value of
   1760       1.1  christos <pre class="example">    "...&lt;...&gt;..."
   1761       1.1  christos </pre>
   1762       1.1  christos   <p><code>AutoOpts</code> does not track suboptions.  You simply note that it is a
   1763       1.1  christos hierarchicly valued option.  <code>AutoOpts</code> does provide a means for searching
   1764       1.1  christos the associated name/value pair list (see: optionFindValue).
   1765       1.1  christos 
   1766       1.1  christos   <p>The command line options relating to configuration and/or usage help are:
   1767       1.1  christos 
   1768       1.1  christos <h5 class="subsubheading">version (-)</h5>
   1769       1.1  christos 
   1770       1.1  christos <p>Print the program version to standard out, optionally with licensing
   1771       1.1  christos information, then exit 0.  The optional argument specifies how much licensing
   1772       1.1  christos detail to provide.  The default is to print just the version.  The licensing infomation may be selected with an option argument. 
   1773       1.1  christos Only the first letter of the argument is examined:
   1774       1.1  christos 
   1775       1.1  christos      <dl>
   1776   1.1.1.7  christos <dt><span class="samp">version</span><dd>Only print the version.  This is the default. 
   1777   1.1.1.7  christos <br><dt><span class="samp">copyright</span><dd>Name the copyright usage licensing terms. 
   1778   1.1.1.7  christos <br><dt><span class="samp">verbose</span><dd>Print the full copyright usage licensing terms. 
   1779       1.1  christos </dl>
   1780       1.1  christos 
   1781       1.1  christos <div class="node">
   1782       1.1  christos <p><hr>
   1783   1.1.1.7  christos <a name="ntp_002dkeygen-exit-status"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntp_002dkeygen-Usage">ntp-keygen Usage</a>,
   1784       1.1  christos Previous:&nbsp;<a rel="previous" accesskey="p" href="#ntp_002dkeygen-config">ntp-keygen config</a>,
   1785       1.1  christos Up:&nbsp;<a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a>
   1786   1.1.1.7  christos <br>
   1787       1.1  christos </div>
   1788       1.1  christos 
   1789       1.1  christos <h4 class="subsection">ntp-keygen exit status</h4>
   1790       1.1  christos 
   1791       1.1  christos <p>One of the following exit values will be returned:
   1792       1.1  christos      <dl>
   1793   1.1.1.7  christos <dt><span class="samp">0 (EXIT_SUCCESS)</span><dd>Successful program execution. 
   1794   1.1.1.7  christos <br><dt><span class="samp">1 (EXIT_FAILURE)</span><dd>The operation failed or the command syntax was not valid. 
   1795   1.1.1.7  christos <br><dt><span class="samp">66 (EX_NOINPUT)</span><dd>A specified configuration file could not be loaded. 
   1796   1.1.1.7  christos <br><dt><span class="samp">70 (EX_SOFTWARE)</span><dd>libopts had an internal operational error.  Please report
   1797       1.1  christos it to autogen-users (a] lists.sourceforge.net.  Thank you. 
   1798       1.1  christos </dl>
   1799       1.1  christos   <div class="node">
   1800       1.1  christos <p><hr>
   1801   1.1.1.7  christos <a name="ntp_002dkeygen-Usage"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntp_002dkeygen-Notes">ntp-keygen Notes</a>,
   1802       1.1  christos Previous:&nbsp;<a rel="previous" accesskey="p" href="#ntp_002dkeygen-exit-status">ntp-keygen exit status</a>,
   1803       1.1  christos Up:&nbsp;<a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a>
   1804   1.1.1.7  christos <br>
   1805       1.1  christos </div>
   1806       1.1  christos 
   1807       1.1  christos <h4 class="subsection">ntp-keygen Usage</h4>
   1808       1.1  christos 
   1809       1.1  christos <div class="node">
   1810       1.1  christos <p><hr>
   1811   1.1.1.7  christos <a name="ntp_002dkeygen-Notes"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntp_002dkeygen-Bugs">ntp-keygen Bugs</a>,
   1812       1.1  christos Previous:&nbsp;<a rel="previous" accesskey="p" href="#ntp_002dkeygen-Usage">ntp-keygen Usage</a>,
   1813       1.1  christos Up:&nbsp;<a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a>
   1814   1.1.1.7  christos <br>
   1815       1.1  christos </div>
   1816       1.1  christos 
   1817       1.1  christos <h4 class="subsection">ntp-keygen Notes</h4>
   1818       1.1  christos 
   1819       1.1  christos <div class="node">
   1820       1.1  christos <p><hr>
   1821   1.1.1.7  christos <a name="ntp_002dkeygen-Bugs"></a>Previous:&nbsp;<a rel="previous" accesskey="p" href="#ntp_002dkeygen-Notes">ntp-keygen Notes</a>,
   1822       1.1  christos Up:&nbsp;<a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a>
   1823   1.1.1.7  christos <br>
   1824       1.1  christos </div>
   1825       1.1  christos 
   1826       1.1  christos <h4 class="subsection">ntp-keygen Bugs</h4>
   1827       1.1  christos 
   1828       1.1  christos <div class="node">
   1829       1.1  christos <p><hr>
   1830   1.1.1.7  christos <a name="Random-Seed-File"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#Cryptographic-Data-Files">Cryptographic Data Files</a>,
   1831       1.1  christos Previous:&nbsp;<a rel="previous" accesskey="p" href="#Running-the-Program">Running the Program</a>,
   1832       1.1  christos Up:&nbsp;<a rel="up" accesskey="u" href="#Top">Top</a>
   1833   1.1.1.7  christos <br>
   1834       1.1  christos </div>
   1835       1.1  christos 
   1836       1.1  christos <!-- node-name,  next,  previous,  up -->
   1837       1.1  christos <h3 class="section">Random Seed File</h3>
   1838       1.1  christos 
   1839       1.1  christos <p>All cryptographically sound key generation schemes must have means to
   1840       1.1  christos randomize the entropy seed used to initialize the internal
   1841       1.1  christos pseudo-random number generator used by the OpenSSL library routines. 
   1842       1.1  christos If a site supports ssh, it is very likely that means to do this are
   1843       1.1  christos already available. 
   1844       1.1  christos The entropy seed used by the OpenSSL library is contained in a file,
   1845       1.1  christos usually called <code>.rnd</code>, which must be available when
   1846       1.1  christos starting the <code>ntp-keygen</code> program or <code>ntpd</code> daemon.
   1847       1.1  christos 
   1848       1.1  christos   <p>The OpenSSL library looks for the file using the path specified by the
   1849       1.1  christos <code>RANDFILE</code> environment variable in the user home directory, whether root
   1850       1.1  christos or some other user. 
   1851       1.1  christos If the <code>RANDFILE</code> environment variable is not
   1852       1.1  christos present, the library looks for the <code>.rnd</code> file in the user home
   1853       1.1  christos directory. 
   1854       1.1  christos Since both the <code>ntp-keygen</code> program and <code>ntpd</code> daemon must run
   1855       1.1  christos as root, the logical place to put this file is in <code>/.rnd</code> or
   1856       1.1  christos <code>/root/.rnd</code>. 
   1857       1.1  christos If the file is not available or cannot be written, the program exits
   1858       1.1  christos with a message to the system log.
   1859       1.1  christos 
   1860       1.1  christos <div class="node">
   1861       1.1  christos <p><hr>
   1862   1.1.1.7  christos <a name="Cryptographic-Data-Files"></a>Previous:&nbsp;<a rel="previous" accesskey="p" href="#Random-Seed-File">Random Seed File</a>,
   1863       1.1  christos Up:&nbsp;<a rel="up" accesskey="u" href="#Top">Top</a>
   1864   1.1.1.7  christos <br>
   1865       1.1  christos </div>
   1866       1.1  christos 
   1867       1.1  christos <!-- node-name,  next,  previous,  up -->
   1868       1.1  christos <h3 class="section">Cryptographic Data Files</h3>
   1869       1.1  christos 
   1870       1.1  christos <p>File and link names are in the <code>form ntpkey_key_name.fstamp</code>,
   1871       1.1  christos where <code>key</code> is the key or parameter type,
   1872       1.1  christos <code>name</code> is the host or group name and
   1873       1.1  christos <code>fstamp</code> is the filestamp (NTP seconds) when the file was created). 
   1874       1.1  christos By convention, key names in generated file names include both upper and
   1875       1.1  christos lower case characters, while key names in generated link names include
   1876       1.1  christos only lower case characters. The filestamp is not used in generated link
   1877       1.1  christos names.
   1878       1.1  christos 
   1879       1.1  christos   <p>The key name is a string defining the cryptographic key type. 
   1880       1.1  christos Key types include public/private keys host and sign, certificate cert
   1881       1.1  christos and several challenge/response key types. 
   1882       1.1  christos By convention, client files used for
   1883       1.1  christos challenges have a par subtype, as in the IFF challenge IFFpar, while
   1884       1.1  christos server files for responses have a key subtype, as in the GQ response
   1885       1.1  christos GQkey.
   1886       1.1  christos 
   1887       1.1  christos   <p>All files begin with two nonencrypted lines. The first line contains
   1888       1.1  christos the file name in the format <code>ntpkey_key_host.fstamp</code>. 
   1889       1.1  christos The second line contains the datestamp in conventional Unix date format. 
   1890       1.1  christos Lines beginning with <code>#</code> are ignored.
   1891       1.1  christos 
   1892       1.1  christos   <p>The remainder of the file contains cryptographic data encoded first
   1893       1.1  christos using ASN.1 rules, then encrypted using the DES-CBC algorithm with
   1894       1.1  christos given password and finally written in PEM-encoded printable ASCII text
   1895       1.1  christos preceded and followed by MIME content identifier lines.
   1896       1.1  christos 
   1897       1.1  christos   <p>The format of the symmetric keys file, ordinarily named <code>ntp.keys</code>,
   1898       1.1  christos is somewhat different than the other files in the interest of backward
   1899       1.1  christos compatibility. 
   1900       1.1  christos Ordinarily, the file is generated by this program, but
   1901       1.1  christos it can be constructed and edited using an ordinary text editor.
   1902       1.1  christos 
   1903       1.1  christos <pre class="example">    # ntpkey_MD5key_hms.local.3564038757
   1904       1.1  christos     # Sun Dec  9 02:45:57 2012
   1905       1.1  christos     
   1906       1.1  christos      1 MD5 "]!ghT%O;3)WJ,/Nc:&gt;I  # MD5 key
   1907       1.1  christos      2 MD5 lu+H^tF46BKR-6~pV_5  # MD5 key
   1908       1.1  christos      3 MD5 :lnoVsE%Yz*avh%EtNC  # MD5 key
   1909       1.1  christos      4 MD5 |fdZrf0sF~^V  # MD5 key
   1910       1.1  christos      5 MD5 IyAG&gt;O"y"LmCRS!*bHC  # MD5 key
   1911       1.1  christos      6 MD5 "&gt;e\A  # MD5 key
   1912       1.1  christos      7 MD5 c9x=M'CfLxax9v)PV-si  # MD5 key
   1913       1.1  christos      8 MD5 E|=jvFVov?Bn|Ev=&amp;aK\  # MD5 key
   1914       1.1  christos      9 MD5 T!c4UT&amp;`(m$+m+B6,`Q0  # MD5 key
   1915       1.1  christos     10 MD5 JVF/1=)=IFbHbJQz..Cd  # MD5 key
   1916       1.1  christos     11 SHA1 6dea311109529e436c2b4fccae9bc753c16d1b48  # SHA1 key
   1917       1.1  christos     12 SHA1 7076f373d86c4848c59ff8046e49cb7d614ec394  # SHA1 key
   1918       1.1  christos     13 SHA1 5f48b1b60591eb01b7cf1d33b7774f08d20262d3  # SHA1 key
   1919       1.1  christos     14 SHA1 eed5ab9d9497319ec60cf3781d52607e76720178  # SHA1 key
   1920       1.1  christos     15 SHA1 f283562611a04c964da8126296f5f8e58c3f85de  # SHA1 key
   1921       1.1  christos     16 SHA1 1930da171297dd63549af50b29449de17dcf341f  # SHA1 key
   1922       1.1  christos     17 SHA1 fee892110358cd4382322b889869e750db8e8a8f  # SHA1 key
   1923       1.1  christos     18 SHA1 b5520c9fadd7ad3fd8bfa061c8821b65d029bb37  # SHA1 key
   1924       1.1  christos     19 SHA1 8c74fb440ec80f453ec6aaa62b9baed0ab723b92  # SHA1 key
   1925       1.1  christos     20 SHA1 6bc05f734306a189326000970c19b3910f403795  # SHA1 key
   1926       1.1  christos </pre>
   1927       1.1  christos   <p>Figure 1. Typical Symmetric Key File
   1928       1.1  christos 
   1929       1.1  christos   <p>Figure 1 shows a typical symmetric keys file used by the reference
   1930       1.1  christos implementation. 
   1931       1.1  christos Each line of the file contains three fields, first an
   1932  1.1.1.12  christos integer between 1 and 65535, inclusive, representing the key identifier
   1933       1.1  christos used in the server and peer configuration commands. 
   1934       1.1  christos Next is the key type for the message digest algorithm,
   1935       1.1  christos which in the absence of the
   1936       1.1  christos OpenSSL library must be MD5 to designate the MD5 message digest
   1937       1.1  christos algorithm. 
   1938       1.1  christos If the OpenSSL library is installed, the key type can be any
   1939       1.1  christos message digest algorithm supported by that library. 
   1940       1.1  christos However, if
   1941       1.1  christos compatibility with FIPS 140-2 is required, the key type must be either
   1942       1.1  christos SHA or SHA1. 
   1943       1.1  christos The key type can be changed using an ASCII text editor.
   1944       1.1  christos 
   1945       1.1  christos   <p>An MD5 key consists of a printable ASCII string less than or equal to
   1946       1.1  christos 16 characters and terminated by whitespace or a # character. 
   1947       1.1  christos An OpenSSL
   1948       1.1  christos key consists of a hex-encoded ASCII string of 40 characters, which is
   1949       1.1  christos truncated as necessary.
   1950       1.1  christos 
   1951       1.1  christos   <p>Note that the keys used by the <code>ntpq</code> and <code>ntpdc</code> programs are
   1952       1.1  christos checked against passwords requested by the programs and entered by hand,
   1953       1.1  christos so it
   1954       1.1  christos is generally appropriate to specify these keys in human readable ASCII
   1955       1.1  christos format.
   1956       1.1  christos 
   1957       1.1  christos   <p>The <code>ntp-keygen</code> program generates a MD5 symmetric keys file
   1958       1.1  christos <code>ntpkey_MD5key_hostname.filestamp</code>. 
   1959       1.1  christos Since the file contains private
   1960       1.1  christos shared keys, it should be visible only to root and distributed by
   1961       1.1  christos secure means to other subnet hosts. 
   1962       1.1  christos The NTP daemon loads the file <code>ntp.keys</code>, so <code>ntp-keygen</code>
   1963       1.1  christos installs a soft link from this name to the generated file. 
   1964       1.1  christos Subsequently, similar soft links must be installed by
   1965       1.1  christos manual or automated means on the other subnet hosts. 
   1966       1.1  christos While this file is
   1967       1.1  christos not used with the Autokey Version 2 protocol, it is needed to
   1968       1.1  christos authenticate some remote configuration commands used by the <code>ntpq</code> and
   1969       1.1  christos <code>ntpdc</code> utilities.
   1970       1.1  christos 
   1971       1.1  christos </body></html>
   1972       1.1  christos 
   1973