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47 <h1 class="settitle" align="center">NTP Symmetric Key</h1>
56 Next: <a href="#ntp_002ekeys-Description" accesskey="n" rel="next">ntp.keys Description</a>, Previous: <a href="dir.html#Top" accesskey="p" rel="prev">(dir)</a>, Up: <a href="dir.html#Top" accesskey="u" rel="up">(dir)</a> </p>
58 <a name="NTP_0027s-Symmetric-Key-File-User-Manual"></a>
59 <h1 class="top">NTP’s Symmetric Key File User Manual</h1>
61 <p>This document describes the symmetric key file for the NTP Project’s
62 <code>ntpd</code> program.
64 <p>This document applies to version 4.2.8p15 of <code>ntp.keys</code>.
66 <a name="SEC_Overview"></a>
67 <h2 class="shortcontents-heading">Short Table of Contents</h2>
69 <div class="shortcontents">
70 <ul class="no-bullet">
71 <li><a name="stoc-Description" href="#toc-Description">1 Description</a></li>
76 <table class="menu" border="0" cellspacing="0">
77 <tr><td align="left" valign="top">• <a href="#ntp_002ekeys-Description" accesskey="1">ntp.keys Description</a>:</td><td> </td><td align="left" valign="top">
79 <tr><td align="left" valign="top">• <a href="#ntp_002ekeys-Notes" accesskey="2">ntp.keys Notes</a>:</td><td> </td><td align="left" valign="top">
84 <a name="ntp_002ekeys-Description"></a>
87 Previous: <a href="#Top" accesskey="p" rel="prev">Top</a>, Up: <a href="#Top" accesskey="u" rel="up">Top</a> </p>
89 <a name="Description"></a>
90 <h2 class="chapter">1 Description</h2>
92 <p>The name and location of the symmetric key file for <code>ntpd</code> can
93 be specified in a configuration file, by default <code>/etc/ntp.keys</code>.
95 <table class="menu" border="0" cellspacing="0">
96 <tr><td align="left" valign="top">• <a href="#ntp_002ekeys-Notes" accesskey="1">ntp.keys Notes</a>:</td><td> </td><td align="left" valign="top">
101 <a name="ntp_002ekeys-Notes"></a>
104 Previous: <a href="#ntp_002ekeys-See-Also" accesskey="p" rel="prev">ntp.keys See Also</a>, Up: <a href="#ntp_002ekeys-Description" accesskey="u" rel="up">ntp.keys Description</a> </p>
106 <a name="Notes-about-ntp_002ekeys"></a>
107 <h3 class="section">1.1 Notes about ntp.keys</h3>
108 <a name="index-ntp_002ekeys"></a>
109 <a name="index-NTP-symmetric-key-file-format"></a>
113 <p>This document describes the format of an NTP symmetric key file.
114 For a description of the use of this type of file, see the
115 "Authentication Support"
117 <code>ntp.conf(5)</code>
120 <p><code>ntpd(8)</code>
121 reads its keys from a file specified using the
123 command line option or the
125 statement in the configuration file.
126 While key number 0 is fixed by the NTP standard
128 and may not be changed,
129 one or more keys numbered between 1 and 65535
130 may be arbitrarily set in the keys file.
132 <p>The key file uses the same comment conventions
133 as the configuration file.
134 Key entries use a fixed format of the form
136 <div class="example">
137 <pre class="example"><kbd>keyno</kbd> <kbd>type</kbd> <kbd>key</kbd> <kbd>opt_IP_list</kbd>
142 is a positive integer (between 1 and 65535),
144 is the message digest algorithm,
146 is the key itself, and
147 <kbd>opt_IP_list</kbd>
148 is an optional comma-separated list of IPs
152 that are allowed to serve time.
154 <kbd>opt_IP_list</kbd>
155 may contain an optional
156 <code>/subnetbits</code>
157 specification which identifies the number of bits for
158 the desired subnet of trust.
160 <kbd>opt_IP_list</kbd>
162 any properly-authenticated message will be
167 may be given in a format
177 was built with the OpenSSL library
178 then any digest library supported by that library may be specified.
179 However, if compliance with FIPS 140-2 is required the
186 <p>What follows are some key types, and corresponding formats:
188 <dl compact="compact">
189 <dt><code>MD5</code></dt>
190 <dd><p>The key is 1 to 16 printable characters terminated by
196 (which is the "start of comment" character).
199 <dt><code>SHA</code></dt>
200 <dt><code>SHA1</code></dt>
201 <dt><code>RMD160</code></dt>
202 <dd><p>The key is a hex-encoded ASCII string of 40 characters,
203 which is truncated as necessary.
207 <p>Note that the keys used by the
210 <code>ntpdc(8)</code>
211 programs are checked against passwords
212 requested by the programs and entered by hand,
213 so it is generally appropriate to specify these keys in ASCII format.
215 <p>This section was generated by <strong>AutoGen</strong>,
216 using the <code>agtexi-cmd</code> template and the option descriptions for the <code>ntp.keys</code> program.
217 This software is released under the NTP license, <http://ntp.org/license>.
219 <table class="menu" border="0" cellspacing="0">
220 <tr><td align="left" valign="top">• <a href="#ntp_002ekeys-Files" accesskey="1">ntp.keys Files</a>:</td><td> </td><td align="left" valign="top">Files
222 <tr><td align="left" valign="top">• <a href="#ntp_002ekeys-See-Also" accesskey="2">ntp.keys See Also</a>:</td><td> </td><td align="left" valign="top">See Also
224 <tr><td align="left" valign="top">• <a href="#ntp_002ekeys-Notes" accesskey="3">ntp.keys Notes</a>:</td><td> </td><td align="left" valign="top">Notes
229 <a name="ntp_002ekeys-Files"></a>
232 Next: <a href="#ntp_002ekeys-See-Also" accesskey="n" rel="next">ntp.keys See Also</a>, Up: <a href="#ntp_002ekeys-Notes" accesskey="u" rel="up">ntp.keys Notes</a> </p>
234 <a name="ntp_002ekeys-Files-1"></a>
235 <h4 class="subsection">1.1.1 ntp.keys Files</h4>
236 <dl compact="compact">
237 <dt><samp>/etc/ntp.keys</samp></dt>
238 <dd><p>the default name of the configuration file
242 <a name="ntp_002ekeys-See-Also"></a>
245 Previous: <a href="#ntp_002ekeys-Files" accesskey="p" rel="prev">ntp.keys Files</a>, Up: <a href="#ntp_002ekeys-Notes" accesskey="u" rel="up">ntp.keys Notes</a> </p>
247 <a name="ntp_002ekeys-See-Also-1"></a>
248 <h4 class="subsection">1.1.2 ntp.keys See Also</h4>
249 <p><code>ntp.conf(5)</code>,
250 <code>ntpd(1ntpdmdoc)</code>,
251 <code>ntpdate(1ntpdatemdoc)</code>,
252 <code>ntpdc(1ntpdcmdoc)</code>,
253 <code>sntp(1sntpmdoc)</code>
259 <a name="ntp_002ekeys-Notes-1"></a>
260 <h4 class="subsection">1.1.3 ntp.keys Notes</h4>
261 <p>This document was derived from FreeBSD.