19c2daa00SOllivier Robert<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> 29c2daa00SOllivier Robert<html> 39c2daa00SOllivier Robert <head> 4ea906c41SOllivier Robert <meta http-equiv="content-type" content="text/html;charset=iso-8859-1"> 59c2daa00SOllivier Robert <meta name="generator" content="HTML Tidy, see www.w3.org"> 69c2daa00SOllivier Robert <title>ntp-keygen - generate public and private keys</title> 79c2daa00SOllivier Robert <link href="scripts/style.css" type="text/css" rel="stylesheet"> 89c2daa00SOllivier Robert </head> 99c2daa00SOllivier Robert <body> 109c2daa00SOllivier Robert <h3><tt>ntp-keygen</tt> - generate public and private keys</h3> 112b15cb3dSCy Schubert <p><img src="pic/alice23.gif" alt="gif" align="left"><a href="http://www.eecis.udel.edu/%7emills/pictures.html">from <i>Alice's Adventures in Wonderland</i>, Lewis Carroll</a></p> 129c2daa00SOllivier Robert <p>Alice holds the key.</p> 132b15cb3dSCy Schubert <p>Last update: 14*09100258SXin LI <!-- #BeginDate format:En2m -->11-Jan-2018 11:55<!-- #EndDate --> 152b15cb3dSCy Schubert UTC</p> 169c2daa00SOllivier Robert <br clear="left"> 179c2daa00SOllivier Robert <h4>Related Links</h4> 182b15cb3dSCy Schubert <script type="text/javascript" language="javascript" src="scripts/manual.txt"></script> 199c2daa00SOllivier Robert <h4>Table of Contents</h4> 209c2daa00SOllivier Robert <ul> 212b15cb3dSCy Schubert <li class="inline"><a href="#synop">Synopsis</a></li> 222b15cb3dSCy Schubert <li class="inline"><a href="#descrip">Description</a></li> 232b15cb3dSCy Schubert <li class="inline"><a href="#run">Running the program</a></li> 242b15cb3dSCy Schubert <li class="inline"><a href="#cmd">Command Line Options</a></li> 252b15cb3dSCy Schubert <li class="inline"><a href="#rand">Random Seed File</a></li> 262b15cb3dSCy Schubert <li class="inline"><a href="#fmt">Cryptographic Data Files</a></li> 272b15cb3dSCy Schubert <li class="inline"><a href="#bug">Bugs</a></li> 289c2daa00SOllivier Robert </ul> 299c2daa00SOllivier Robert <hr> 309c2daa00SOllivier Robert <h4 id="synop">Synopsis</h4> 312b15cb3dSCy Schubert <p id="intro"><tt>ntp-keygen [ -deGHIMPT ] [ -b <i>modulus</i> ] [ -c [ RSA-MD2 | RSA-MD5 | RSA-SHA 322b15cb3dSCy Schubert | RSA-SHA1 | RSA-MDC2 | RSA-RIPEMD160 | DSA-SHA | DSA-SHA1 ] ] 332b15cb3dSCy Schubert [ -C <i>cipher</i> ] [-i <i>group</i> ] [ -l <em>days</em>] 342b15cb3dSCy Schubert [ -m <i>modulus</i> ] [ -p <i>passwd1</i> ] [ -q <i>passwd2</i> ] 352b15cb3dSCy Schubert [ -S [ RSA | DSA ] ] [ -s <i>host</i> ] [ -V <i>nkeys</i> ]</tt></p> 369c2daa00SOllivier Robert <h4 id="descrip">Description</h4> 37*09100258SXin LI <p>This program generates cryptographic data files used by the NTPv4 38*09100258SXin LI authentication and identity schemes. It can generate message digest keys 39*09100258SXin LI used in symmetric key cryptography and, if the OpenSSL software library 40*09100258SXin LI has been installed, it can generate host keys, sign keys, certificates, 41*09100258SXin LI and identity keys and parameters used by the Autokey public key 42*09100258SXin LI cryptography. The message digest keys file is generated in a format 43*09100258SXin LI compatible with NTPv3. All other files are in PEM-encoded printable ASCII 44*09100258SXin LI format so they can be embedded as MIME attachments in mail to other 45*09100258SXin LI sites.</p> 46*09100258SXin LI <p>When used to generate message digest keys, the program produces a file 47*09100258SXin LI containing ten pseudo-random printable ASCII strings suitable for the MD5 48*09100258SXin LI message digest algorithm included in the distribution. If the OpenSSL 49*09100258SXin LI library is installed, it produces an additional ten hex-encoded random bit 50*09100258SXin LI strings suitable for the SHA1, AES-128 CMAC, and other message digest 51*09100258SXin LI algorithms. The message digest keys file must be distributed and stored 52*09100258SXin LI using secure means beyond the scope of NTP itself. Besides the keys used 53*09100258SXin LI for ordinary NTP associations, additional keys can be defined as passwords 54*09100258SXin LI for the <tt><a href="ntpq.html">ntpq</a></tt> 55*09100258SXin LI and <tt><a href="ntpdc.html">ntpdc</a></tt> utility programs.</p> 56*09100258SXin LI <p>The remaining generated files are compatible with other OpenSSL 57*09100258SXin LI applications and other Public Key Infrastructure (PKI) 58*09100258SXin LI resources. Certificates generated by this program are compatible with 59*09100258SXin LI extant industry practice, although some users might find the 60*09100258SXin LI interpretation of X509v3 extension fields somewhat liberal. However, 61*09100258SXin LI the identity keys are probably not compatible with anything other than 62*09100258SXin LI Autokey.</p> 63*09100258SXin LI <p>Some files used by this program are encrypted using a private 64*09100258SXin LI password. The <tt>-p</tt> option specifies the password for local 65*09100258SXin LI encrypted files and the <tt>-q</tt> option the password for encrypted 66*09100258SXin LI files sent to remote sites. If no password is specified, the host name 67*09100258SXin LI returned by the Unix <tt>gethostname()</tt> function, normally the DNS 68*09100258SXin LI name of the host, is used.</p> 69*09100258SXin LI <p>The <tt>pw</tt> option of the <tt>crypto</tt> configuration command 70*09100258SXin LI specifies the read password for previously encrypted local files. 71*09100258SXin LI This must match the local password used by this program. If not 72*09100258SXin LI specified, the host name is used. Thus, if files are generated by 73*09100258SXin LI this program without password, they can be read back by <tt>ntpd</tt> 74*09100258SXin LI without password, but only on the same host.</p> 75*09100258SXin LI <p>Normally, encrypted files for each host are generated by that host 76*09100258SXin LI and used only by that host, although exceptions exist as noted later 77*09100258SXin LI on this page. The symmetric keys file, normally 78*09100258SXin LI called <tt>ntp.keys</tt>, is usually installed in <tt>/etc</tt>. 79*09100258SXin LI Other files and links are usually installed 80*09100258SXin LI in <tt>/usr/local/etc</tt>, which is normally in a shared filesystem 81*09100258SXin LI in NFS-mounted networks and cannot be changed by shared clients. The 82*09100258SXin LI location of the keys directory can be changed by the <tt>keysdir</tt> 83*09100258SXin LI configuration command in such cases. Normally, this is 84*09100258SXin LI in <tt>/etc</tt>.</p> 85*09100258SXin LI <p>This program directs commentary and error messages to the standard 86*09100258SXin LI error stream <tt>stderr</tt> and remote files to the standard output 87*09100258SXin LI stream <tt>stdout</tt> where they can be piped to other applications 88*09100258SXin LI or redirected to files. The names used for generated files and links 89*09100258SXin LI all begin with the string <tt>ntpkey</tt> and include the file type, 90*09100258SXin LI generating host and filestamp, as described in 91*09100258SXin LI the <a href="#fmt">Cryptographic Data Files</a> section below</p> 922b15cb3dSCy Schubert <h4 id="run">Running the Program</h4> 93*09100258SXin LI <p>To test and gain experience with Autokey concepts, log in as root and 94*09100258SXin LI change to the keys directory, usually <tt>/usr/local/etc</tt>. When 95*09100258SXin LI run for the first time, or if all files with names 96*09100258SXin LI beginning <tt>ntpkey</tt> have been removed, use 97*09100258SXin LI the <tt>ntp-keygen</tt> command without arguments to generate a 98*09100258SXin LI default RSA host key and matching RSA-MD5 certificate with expiration 99*09100258SXin LI date one year hence. If run again without options, the program uses 100*09100258SXin LI the existing keys and parameters and generates only a new certificate 101*09100258SXin LI with new expiration date one year hence.</p> 102*09100258SXin LI <p>Run the command on as many hosts as necessary. Designate one of them 103*09100258SXin LI as the trusted host (TH) using <tt>ntp-keygen</tt> with 104*09100258SXin LI the <tt>-T</tt> option and configure it to synchronize from reliable 105*09100258SXin LI Internet servers. Then configure the other hosts to synchronize to 106*09100258SXin LI the TH directly or indirectly. A certificate trail is created when 107*09100258SXin LI Autokey asks the immediately ascendant host towards the TH to sign its 108*09100258SXin LI certificate, which is then provided to the immediately descendant host 109*09100258SXin LI on request. All group hosts should have acyclic certificate trails 110*09100258SXin LI ending on the TH.</p> 111*09100258SXin LI <p>The host key is used to encrypt the cookie when required and so must 112*09100258SXin LI be RSA type. By default, the host key is also the sign key used to 113*09100258SXin LI encrypt signatures. A different sign key can be assigned using 114*09100258SXin LI the <tt>-S</tt> option and this can be either RSA or DSA type. By 115*09100258SXin LI default, the signature message digest type is MD5, but any combination 116*09100258SXin LI of sign key type and message digest type supported by the OpenSSL 117*09100258SXin LI library can be specified using the <tt>-c</tt> option.</p> 118*09100258SXin LI <p>The rules say cryptographic media should be generated with proventic 119*09100258SXin LI filestamps, which means the host should already be synchronized before 120*09100258SXin LI this program is run. This of course creates a chicken-and-egg problem 121*09100258SXin LI when the host is started for the first time. Accordingly, the host 122*09100258SXin LI time should be set by some other means, such as 123*09100258SXin LI eyeball-and-wristwatch, at least so that the certificate lifetime is 124*09100258SXin LI within the current year. After that and when the host is synchronized 125*09100258SXin LI to a proventic source, the certificate should be re-generated.</p> 126*09100258SXin LI <p>Additional information on trusted groups and identity schemes is on 127*09100258SXin LI the <a href="autokey.html">Autokey Public-Key Authentication</a> 128*09100258SXin LI page.</p> 1299c2daa00SOllivier Robert <h4 id="cmd">Command Line Options</h4> 1309c2daa00SOllivier Robert <dl> 1312b15cb3dSCy Schubert <dt><tt>-b <i>modulus</i></tt></dt> 132*09100258SXin LI <dd>Set the modulus for generating identity keys to <i>modulus</i> 133*09100258SXin LI bits. The modulus defaults to 256, but can be set from 256 (32 134*09100258SXin LI octets) to 2048 (256 octets). Use the larger moduli with caution, 135*09100258SXin LI as this can consume considerable computing resources and increases 136*09100258SXin LI the size of authenticated packets.</dd> 1372b15cb3dSCy Schubert <dt><tt>-c [ RSA-MD2 | RSA-MD5 | RSA-SHA | RSA-SHA1 | RSA-MDC2 | RSA-RIPEMD160 | DSA-SHA | DSA-SHA1 ]</tt></dt> 138*09100258SXin LI <dd>Select certificate digital signature and message digest scheme. 139*09100258SXin LI Note that RSA schemes must be used with an RSA sign key and DSA 140*09100258SXin LI schemes must be used with a DSA sign key. The default without this 141*09100258SXin LI option is <tt>RSA-MD5</tt>. If compatibility with FIPS 140-2 is 142*09100258SXin LI required, either the <tt>DSA-SHA</tt> or <tt>DSA-SHA1</tt> scheme 143*09100258SXin LI must be used.</dd> 1442b15cb3dSCy Schubert <dt><tt>-C <i>cipher</i></tt></dt> 145*09100258SXin LI <dd>Select the OpenSSL cipher to use for password-protected keys. 146*09100258SXin LI The <tt>openssl -h</tt> command provided with OpenSSL displays 147*09100258SXin LI available ciphers. The default without this option 148*09100258SXin LI is <tt>des-ede3-cbc</tt>.</dd> 1492b15cb3dSCy Schubert <dt><tt>-d</tt></dt> 150*09100258SXin LI <dd>Enable debugging. This option displays the cryptographic data 151*09100258SXin LI produced for eye-friendly billboards.</dd> 1522b15cb3dSCy Schubert <dt><tt>-e</tt></dt> 153*09100258SXin LI <dd>Extract the IFF or GQ public parameters from the <tt>IFFkey</tt> 154*09100258SXin LI or <tt>GQkey</tt> keys file previously specified. Send the 155*09100258SXin LI unencrypted data to the standard output stream <tt>stdout</tt>.</dd> 1562b15cb3dSCy Schubert <dt><tt>-G</tt></dt> 157*09100258SXin LI <dd>Generate a new encrypted GQ key file for the Guillou-Quisquater 158*09100258SXin LI (GQ) identity scheme. This option is mutually exclusive with 159*09100258SXin LI the <tt>-I</tt> and <tt>-V</tt> options.</dd> 1602b15cb3dSCy Schubert <dt><tt>-H</tt></dt> 1612b15cb3dSCy Schubert <dd>Generate a new encrypted RSA public/private host key file.</dd> 1622b15cb3dSCy Schubert <dt><tt>-i <i>group</i></tt></dt> 163*09100258SXin LI <dd>Set the optional Autokey group name to <tt><i>group</i></tt>. This 164*09100258SXin LI is used in the identity scheme parameter file names. In that role, 165*09100258SXin LI the default is the host name if no group is provided. The group 166*09100258SXin LI name, if specified using <tt>-i</tt> or using <tt>-s</tt> following 167*09100258SXin LI an <tt>@</tt> character, is also used in certificate subject and 168*09100258SXin LI issuer names in the form <tt><i>host</i>@<i>group</i></tt> and 169*09100258SXin LI should match the group specified via <tt>crypto ident</tt> 170*09100258SXin LI or <tt>server ident</tt> in ntpd's configuration file.</dd> 1712b15cb3dSCy Schubert <dt><tt>-I</tt></dt> 172*09100258SXin LI <dd>Generate a new encrypted IFF key file for the Schnorr (IFF) 173*09100258SXin LI identity scheme. This option is mutually exclusive with 174*09100258SXin LI the <tt>-G</tt> and <tt>-V</tt> options.</dd> 1752b15cb3dSCy Schubert <dt><tt>-l <i>days</i></tt></dt> 176*09100258SXin LI <dd>Set the lifetime for certificates to <tt><i>days</i></tt>. The 177*09100258SXin LI default lifetime is one year (365 d).</dd> 1782b15cb3dSCy Schubert <dt><tt>-m <i>modulus</i></tt></dt> 179*09100258SXin LI <dd>Set the modulus for generating files to <i>modulus</i> bits. The 180*09100258SXin LI modulus defaults to 512, but can be set from 256 (32 octets) to 2048 181*09100258SXin LI (256 octets). Use the larger moduli with caution, as this can 182*09100258SXin LI consume considerable computing resources and increases the size of 183*09100258SXin LI authenticated packets.</dd> 1842b15cb3dSCy Schubert <dt><tt>-M</tt></dt> 185*09100258SXin LI <dd>Generate a new keys file containing 10 MD5 keys and 10 SHA keys. 186*09100258SXin LI An MD5 key is a string of 20 random printable ASCII characters, 187*09100258SXin LI while a SHA key is a string of 40 random hex digits. The file can be 188*09100258SXin LI edited using a text editor to change the key type or key content. 189*09100258SXin LI This option is mutually exclusive with all other options.</dd> 1902b15cb3dSCy Schubert <dt><tt>-P</tt></dt> 191*09100258SXin LI <dd>Generate a new private certificate used by the PC identity scheme. 192*09100258SXin LI By default, the program generates public certificates. Note: the PC 193*09100258SXin LI identity scheme is not recommended for new installations.</dd> 1942b15cb3dSCy Schubert <dt><tt>-p <i>passwd</i></tt></dt> 195*09100258SXin LI <dd>Set the password for reading and writing encrypted files 196*09100258SXin LI to <tt><i>passwd</i></tt>. These include the host, sign and 197*09100258SXin LI identify key files. By default, the password is the string returned 198*09100258SXin LI by the Unix <tt>gethostname()</tt> routine.</dd> 1992b15cb3dSCy Schubert <dt><tt>-q <i>passwd</i></tt></dt> 200*09100258SXin LI <dd>Set the password for writing encrypted IFF, GQ and MV identity 201*09100258SXin LI files redirected to <tt>stdout</tt> to <tt><i>passwd</i></tt>=. In 202*09100258SXin LI effect, these files are decrypted with the <tt>-p</tt> password, 203*09100258SXin LI then encrypted with the <tt>-q</tt> password. By default, the 204*09100258SXin LI password is the string returned by the Unix <tt>gethostname()</tt> 205*09100258SXin LI routine.</dd> 2062b15cb3dSCy Schubert <dt><tt>-S [ RSA | DSA ]</tt></dt> 207*09100258SXin LI <dd>Generate a new encrypted public/private sign key file of the 208*09100258SXin LI specified type. By default, the sign key is the host key and has 209*09100258SXin LI the same type. If compatibly with FIPS 140-2 is required, the sign 210*09100258SXin LI key type must be <tt>DSA</tt>.</dd> 2112b15cb3dSCy Schubert <dt><tt>-s <i>host</i>[@<i>group</i>]</tt></dt> 212*09100258SXin LI <dd>Specify the Autokey host name, where <tt><i>host</i></tt> is the 213*09100258SXin LI host name and <tt><i>group</i></tt> is the optional group name. The 214*09100258SXin LI host name, and if provided, group name are used 215*09100258SXin LI in <tt><i>host</i>@<i>group</i></tt> form as certificate subject and 216*09100258SXin LI issuer. Specifying <tt>-s @<i>group</i></tt> is allowed, and 217*09100258SXin LI results in leaving the host name unchanged, as 218*09100258SXin LI with <tt>-i <i>group</i></tt>. The group name, or if no group is 219*09100258SXin LI provided, the host name are also used in the file names of IFF, GQ, 220*09100258SXin LI and MV identity scheme parameter files. If <tt><i>host</i></tt> is 221*09100258SXin LI not specified, the default host name is the string returned by 222*09100258SXin LI the <tt>gethostname()</tt> routine.</dd> 2232b15cb3dSCy Schubert <dt><tt>-T</tt></dt> 224*09100258SXin LI <dd>Generate a trusted certificate. By default, the program generates 225*09100258SXin LI nontrusted certificates.</dd> 2262b15cb3dSCy Schubert <dt><tt>-V <i>nkeys</i></tt></dt> 227*09100258SXin LI <dd>Generate <tt>nkeys</tt> encrypted server keys for the 228*09100258SXin LI Mu-Varadharajan (MV) identity scheme. This option is mutually 229*09100258SXin LI exclusive with the <tt>-I</tt> and <tt>-G</tt> options. Note: 230*09100258SXin LI support for this option should be considered a work in 231*09100258SXin LI progress.</dd> 2329c2daa00SOllivier Robert </dl> 2339c2daa00SOllivier Robert <h4 id="rand">Random Seed File</h4> 234*09100258SXin LI <p>All cryptographically sound key generation schemes must have means to 235*09100258SXin LI randomize the entropy seed used to initialize the internal 236*09100258SXin LI pseudo-random number generator used by the OpenSSL library routines. 237*09100258SXin LI If a site supports <tt>ssh</tt>, it is very likely that means to do 238*09100258SXin LI this are already available. The entropy seed used by the OpenSSL 239*09100258SXin LI library is contained in a file, usually called <tt>.rnd</tt>, which 240*09100258SXin LI must be available when starting the <tt>ntp-keygen</tt> program 241*09100258SXin LI or <tt>ntpd</tt> daemon.</p> 242*09100258SXin LI <p>The OpenSSL library looks for the file using the path specified by 243*09100258SXin LI the <tt>RANDFILE</tt> environment variable in the user home directory, 244*09100258SXin LI whether root or some other user. If the <tt>RANDFILE</tt> environment 245*09100258SXin LI variable is not present, the library looks for the <tt>.rnd</tt> file 246*09100258SXin LI in the user home directory. Since both the <tt>ntp-keygen</tt> 247*09100258SXin LI program and <tt>ntpd</tt> daemon must run as root, the logical place 248*09100258SXin LI to put this file is in <tt>/.rnd</tt> or <tt>/root/.rnd</tt>. If the 249*09100258SXin LI file is not available or cannot be written, the program exits with a 250*09100258SXin LI message to the system log.</p> 2512b15cb3dSCy Schubert <h4 id="fmt">Cryptographic Data Files</h4> 252*09100258SXin LI <p>File and link names are in the 253*09100258SXin LI form <tt>ntpkey_<i>key</i>_<i>name</i>.<i>fstamp</i></tt>, 254*09100258SXin LI where <tt><i>key</i></tt> is the key or parameter 255*09100258SXin LI type, <tt><i>name</i></tt> is the host or group name 256*09100258SXin LI and <tt><i>fstamp</i></tt> is the filestamp (NTP seconds) when the 257*09100258SXin LI file was created). By convention, <em><tt>key</tt></em> names in 258*09100258SXin LI generated file names include both upper and lower case characters, 259*09100258SXin LI while <em><tt>key</tt></em> names in generated link names include only 260*09100258SXin LI lower case characters. The filestamp is not used in generated link 261*09100258SXin LI names.</p> 262*09100258SXin LI <p>The <em><tt>key</tt></em> name is a string defining the cryptographic 263*09100258SXin LI key type. Key types include public/private keys <tt>host</tt> 264*09100258SXin LI and <tt>sign</tt>, certificate <tt>cert</tt> and several 265*09100258SXin LI challenge/response key types. By convention, client files used for 266*09100258SXin LI challenges have a <tt>par</tt> subtype, as in the IFF 267*09100258SXin LI challenge <tt>IFFpar</tt>, while server files for responses have 268*09100258SXin LI a <tt>key</tt> subtype, as in the GQ response <tt>GQkey</tt>.</p> 269*09100258SXin LI <p>All files begin with two nonencrypted lines. The first line contains 270*09100258SXin LI the file name in the 271*09100258SXin LI format <tt>ntpkey_<i>key</i>_<i>host</i>.<i>fstamp</i></tt>. The second 272*09100258SXin LI line contains the datestamp in conventional Unix <tt>date</tt> format. 273*09100258SXin LI Lines beginning with <tt>#</tt> are ignored.</p> 274*09100258SXin LI <p>The remainder of the file contains cryptographic data encoded first 275*09100258SXin LI using ASN.1 rules, then encrypted using the DES-CBC algorithm with 276*09100258SXin LI given password and finally written in PEM-encoded printable ASCII text 277*09100258SXin LI preceded and followed by MIME content identifier lines.</p> 278*09100258SXin LI <p>The format of the symmetric keys file, ordinarily 279*09100258SXin LI named <tt>ntp.keys,</tt> is somewhat different than the other files in 280*09100258SXin LI the interest of backward compatibility. Ordinarily, the file is 281*09100258SXin LI generated by this program, but it can be constructed and edited using 282*09100258SXin LI an ordinary text editor.</p> 283*09100258SXin LI <table> 284*09100258SXin LI <caption style="caption-side: bottom;"> 285*09100258SXin LI Figure 1. Typical Symmetric Key File 286*09100258SXin LI </caption> 287*09100258SXin LI <tr><td style="border: 1px solid black; border-spacing: 0;"> 288*09100258SXin LI <pre style="color:grey;"> 289*09100258SXin LI # ntpkey_MD5key_bk.ntp.org.3595864945 290*09100258SXin LI # Thu Dec 12 19:22:25 2013 291*09100258SXin LI 292*09100258SXin LI 1 MD5 L";Nw<`.I<f4U0)247"i # MD5 key 293*09100258SXin LI 2 MD5 &>l0%XXK9O'51VwV<xq~ # MD5 key 294*09100258SXin LI 3 MD5 lb4zLW~d^!K:]RsD'qb6 # MD5 key 295*09100258SXin LI 4 MD5 Yue:tL[+vR)M`n~bY,'? # MD5 key 296*09100258SXin LI 5 MD5 B;fxlKgr/&4ZTbL6=RxA # MD5 key 297*09100258SXin LI 6 MD5 4eYwa`o}3i@@V@..R9!l # MD5 key 298*09100258SXin LI 7 MD5 `A.([h+;wTQ|xfi%Sn_! # MD5 key 299*09100258SXin LI 8 MD5 45:V,r4]l6y^JH6.Sh?F # MD5 key 300*09100258SXin LI 9 MD5 3-5vcn*6l29DS?Xdsg)* # MD5 key 301*09100258SXin LI 10 MD5 2late4Me # MD5 key 302*09100258SXin LI 11 SHA1 a27872d3030a9025b8446c751b4551a7629af65c # SHA1 key 303*09100258SXin LI 12 SHA1 21bc3b4865dbb9e920902abdccb3e04ff97a5e74 # SHA1 key 304*09100258SXin LI 13 SHA1 2b7736fe24fef5ba85ae11594132ab5d6f6daba9 # SHA1 key 305*09100258SXin LI 14 SHA a5332809c8878dd3a5b918819108a111509aeceb # SHA key 306*09100258SXin LI 15 MD2 2fe16c88c760ff2f16d4267e36c1aa6c926e6964 # MD2 key 307*09100258SXin LI 16 MD4 b2691811dc19cfc0e2f9bcacd74213f29812183d # MD4 key 308*09100258SXin LI 17 MD5 e4d6735b8bdad58ec5ffcb087300a17f7fef1f7c # MD5 key 309*09100258SXin LI 18 MDC2 a8d5e2315c025bf3a79174c87fbd10477de2eabc # MDC2 key 310*09100258SXin LI 19 RIPEMD160 77ca332cafb30e3cafb174dcd5b80ded7ba9b3d2 # RIPEMD160 key 311*09100258SXin LI 20 AES128CMAC f92ff73eee86c1e7dc638d6489a04e4e555af878 # AES128CMAC key 312*09100258SXin LI 21 MD5 sampo 10.1.2.3/24 313*09100258SXin LI </pre></td></tr></table> 314*09100258SXin LI <p>Figure 1 shows a typical symmetric keys file used by the reference 315*09100258SXin LI implementation. Each line of the file contains three or four fields, 316*09100258SXin LI first an integer between 1 and 65534, inclusive, representing the key 317*09100258SXin LI identifier used in the <tt>server</tt> and <tt>peer</tt> configuration 318*09100258SXin LI commands. Second is the key type for the message digest algorithm, 319*09100258SXin LI which in the absence of the OpenSSL library must be <tt>MD5</tt> to 320*09100258SXin LI designate the MD5 message digest algorithm. If the OpenSSL library is 321*09100258SXin LI installed, the key type can be any message digest algorithm supported 322*09100258SXin LI by that library. However, if compatibility with FIPS 140-2 is 323*09100258SXin LI required, the key type must be either <tt>SHA</tt> or <tt>SHA1</tt>. 324*09100258SXin LI The key type can be changed using an ASCII text editor.</p> 325*09100258SXin LI <p>The third field is the key.</p> 326*09100258SXin LI <p>An MD5 key consists of a printable ASCII string less than or equal to 327*09100258SXin LI 16 characters and terminated by whitespace or a # character. An 328*09100258SXin LI OpenSSL key consists of a hex-encoded ASCII string of 40 characters, 329*09100258SXin LI which is truncated as necessary.</p> 330*09100258SXin LI <p>Note that the keys used by the <tt>ntpq</tt> and <tt>ntpdc</tt> 331*09100258SXin LI programs are checked against passwords requested by the programs and 332*09100258SXin LI entered by hand, so it is generally appropriate to specify these keys 333*09100258SXin LI in human readable ASCII format.</p> 334*09100258SXin LI <p>The optional fourth field is one or more IPs, with each IP separated 335*09100258SXin LI with a comma. An IP may end with an optional <tt>/subnetbits</tt> 336*09100258SXin LI suffix, which limits the acceptance of the key identifier to packets 337*09100258SXin LI claiming to be from the described IP space.</p> 338*09100258SXin LI <p>The <tt>ntp-keygen</tt> program generates a MD5 symmetric keys 339*09100258SXin LI file <tt>ntpkey_MD5key_<i>hostname.filestamp</i></tt>. Since the file 340*09100258SXin LI contains private shared keys, it should be visible only to root and 341*09100258SXin LI distributed by secure means to other subnet hosts. The NTP daemon 342*09100258SXin LI loads the file <tt>ntp.keys</tt>, so <tt>ntp-keygen</tt> installs a 343*09100258SXin LI soft link from this name to the generated file. Subsequently, similar 344*09100258SXin LI soft links must be installed by manual or automated means on the other 345*09100258SXin LI subnet hosts. While this file is not used with the Autokey Version 2 346*09100258SXin LI protocol, it is needed to authenticate some remote configuration 347*09100258SXin LI commands used by the <a href="ntpq.html"><tt>ntpq</tt></a> 348*09100258SXin LI and <a href="ntpdc.html"><tt>ntpdc</tt></a> utilities.</p> 3499c2daa00SOllivier Robert <h4 id="bug">Bugs</h4> 350*09100258SXin LI <p>It can take quite a while to generate some cryptographic values.</p> 3519c2daa00SOllivier Robert <hr> 3529c2daa00SOllivier Robert <script type="text/javascript" language="javascript" src="scripts/footer.txt"></script> 3539c2daa00SOllivier Robert </body> 3549c2daa00SOllivier Robert</html> 355
