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1 <html lang="en"> 2 <head> 3 <title>Ntp-keygen User's Manual</title> 4 <meta http-equiv="Content-Type" content="text/html"> 5 <meta name="description" content="Ntp-keygen User's Manual"> 6 <meta name="generator" content="makeinfo 4.7"> 7 <link title="Top" rel="top" href="#Top"> 8 <link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage"> 9 <meta http-equiv="Content-Style-Type" content="text/css"> 10 <style type="text/css"><!-- 11 pre.display { font-family:inherit } 12 pre.format { font-family:inherit } 13 pre.smalldisplay { font-family:inherit; font-size:smaller } 14 pre.smallformat { font-family:inherit; font-size:smaller } 15 pre.smallexample { font-size:smaller } 16 pre.smalllisp { font-size:smaller } 17 span.sc { font-variant:small-caps } 18 span.roman { font-family: serif; font-weight: normal; } 19 --></style> 20 </head> 21 <body> 22 <h1 class="settitle">Ntp-keygen User's Manual</h1> 23 <div class="shortcontents"> 24 <h2>Short Contents</h2> 25 <ul> 26 <a href="#Top">Top</a> 27 <a href="#Top">NTP Key Generation Program User Manual</a> 28 </ul> 29 </div> 30 31 32 33 <div class="node"> 34 <p><hr> 35 <a name="Top"></a>Up: <a rel="up" accesskey="u" href="#dir">(dir)</a> 36 <br> 37 </div> 38 39 <h2 class="unnumbered">Top</h2> 40 41 <ul class="menu"> 42 <li><a accesskey="1" href="#Description">Description</a> 43 <li><a accesskey="2" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a>: Invoking ntp-keygen 44 <li><a accesskey="3" href="#Running-the-Program">Running the Program</a> 45 <li><a accesskey="4" href="#Random-Seed-File">Random Seed File</a> 46 <li><a accesskey="5" href="#Cryptographic-Data-Files">Cryptographic Data Files</a> 47 </ul> 48 49 <div class="node"> 50 <p><hr> 51 <a name="Top"></a>Next: <a rel="next" accesskey="n" href="#Description">Description</a>, 52 Previous: <a rel="previous" accesskey="p" href="#dir">(dir)</a>, 53 Up: <a rel="up" accesskey="u" href="#dir">(dir)</a> 54 <br> 55 </div> 56 57 <h2 class="unnumbered">NTP Key Generation Program User Manual</h2> 58 59 <p>This document describes the use of the NTP Project's <code>ntp-keygen</code> 60 program, that generates cryptographic data files used by the NTPv4 61 authentication and identity schemes. 62 It can generate message digest keys used in symmetric key cryptography and, 63 if the OpenSSL software 64 library has been installed, it can generate host keys, sign keys, 65 certificates, and identity keys and parameters used by the Autokey 66 public key cryptography. 67 The message digest keys file is generated in a 68 format compatible with NTPv3. 69 All other files are in PEM-encoded 70 printable ASCII format so they can be embedded as MIME attachments in 71 mail to other sites. 72 73 <p>This document applies to version 4.2.8 of <code>ntp-keygen</code>. 74 75 <div class="node"> 76 <p><hr> 77 <a name="Description"></a>Next: <a rel="next" accesskey="n" href="#Running-the-Program">Running the Program</a>, 78 Previous: <a rel="previous" accesskey="p" href="#Top">Top</a>, 79 Up: <a rel="up" accesskey="u" href="#Top">Top</a> 80 <br> 81 </div> 82 83 <!-- node-name, next, previous, up --> 84 <h3 class="section">Description</h3> 85 86 <p>This program generates cryptographic data files used by the NTPv4 87 authentication and identity schemes. It can generate message digest 88 keys used in symmetric key cryptography and, if the OpenSSL software 89 library has been installed, it can generate host keys, sign keys, 90 certificates, and identity keys and parameters used by the Autokey 91 public key cryptography. The message digest keys file is generated in a 92 format compatible with NTPv3. All other files are in PEM-encoded 93 printable ASCII format so they can be embedded as MIME attachments in 94 mail to other sites. 95 96 <p>When used to generate message digest keys, the program produces a file 97 containing ten pseudo-random printable ASCII strings suitable for the 98 MD5 message digest algorithm included in the distribution. 99 If the 100 OpenSSL library is installed, it produces an additional ten hex-encoded 101 random bit strings suitable for the SHA1 and other message digest 102 algorithms. 103 The message digest keys file must be distributed and stored 104 using secure means beyond the scope of NTP itself. 105 Besides the keys 106 used for ordinary NTP associations, additional keys can be defined as 107 passwords for the ntpq and ntpdc utility programs. 108 109 <p>The remaining generated files are compatible with other OpenSSL 110 applications and other Public Key Infrastructure (PKI) resources. 111 Certificates generated by this program are compatible with extant 112 industry practice, although some users might find the interpretation of 113 X509v3 extension fields somewhat liberal. 114 However, the identity keys 115 are probably not compatible with anything other than Autokey. 116 117 <p>Some files used by this program are encrypted using a private password. 118 The <code>-p</code> option specifies the password for local encrypted files and the 119 <code>-q</code> option the password for encrypted files sent to remote sites. 120 If no password is specified, the host name returned by the Unix 121 <code>gethostname()</code> function, normally the DNS name of the host, is used. 122 123 <p>The <kbd>pw</kbd> option of the <code>crypto</code> configuration command 124 specifies the read password for previously encrypted local files. 125 This must match the local password used by this program. 126 If not specified, the host name is used. 127 Thus, if files are generated by this program without password, 128 they can be read back by ntpd without password, but only on the same 129 host. 130 131 <p>Normally, encrypted files for each host are generated by that host and 132 used only by that host, although exceptions exist as noted later on 133 this page. 134 The symmetric keys file, normally called <code>ntp.keys</code>, is 135 usually installed in <code>/etc</code>. 136 Other files and links are usually installed 137 in <code>/usr/local/etc</code>, which is normally in a shared filesystem in 138 NFS-mounted networks and cannot be changed by shared clients. 139 The location of the keys directory can be changed by the keysdir 140 configuration command in such cases. 141 Normally, this is in <code>/etc</code>. 142 143 <p>This program directs commentary and error messages to the standard 144 error stream <code>stderr</code> and remote files to the standard output stream 145 <code>stdout</code> where they can be piped to other applications or redirected to 146 files. 147 The names used for generated files and links all begin with the 148 string <code>ntpkey</code> and include the file type, 149 generating host and filestamp, 150 as described in the <a href="#Cryptographic-Data-Files">Cryptographic Data Files</a> section below. 151 152 <div class="node"> 153 <p><hr> 154 <a name="Running-the-Program"></a>Next: <a rel="next" accesskey="n" href="#Random-Seed-File">Random Seed File</a>, 155 Previous: <a rel="previous" accesskey="p" href="#Description">Description</a>, 156 Up: <a rel="up" accesskey="u" href="#Top">Top</a> 157 <br> 158 </div> 159 160 <!-- node-name, next, previous, up --> 161 <h3 class="section">Running the Program</h3> 162 163 <p>To test and gain experience with Autokey concepts, log in as root and 164 change to the keys directory, usually <code>/usr/local/etc</code>. 165 When run for the 166 first time, or if all files with names beginning <code>ntpkey</code>] have been 167 removed, use the <code>ntp-keygen</code> command without arguments to generate a 168 default RSA host key and matching RSA-MD5 certificate with expiration 169 date one year hence. 170 If run again without options, the program uses the 171 existing keys and parameters and generates only a new certificate with 172 new expiration date one year hence. 173 174 <p>Run the command on as many hosts as necessary. 175 Designate one of them as the trusted host (TH) using <code>ntp-keygen</code> 176 with the <code>-T</code> option and configure 177 it to synchronize from reliable Internet servers. 178 Then configure the other hosts to synchronize to the TH directly or indirectly. 179 A certificate trail is created when Autokey asks the immediately 180 ascendant host towards the TH to sign its certificate, which is then 181 provided to the immediately descendant host on request. 182 All group hosts should have acyclic certificate trails ending on the TH. 183 184 <p>The host key is used to encrypt the cookie when required and so must be 185 RSA type. 186 By default, the host key is also the sign key used to encrypt signatures. 187 A different sign key can be assigned using the <code>-S</code> option 188 and this can be either RSA or DSA type. 189 By default, the signature 190 message digest type is MD5, but any combination of sign key type and 191 message digest type supported by the OpenSSL library can be specified 192 using the <code>-c</code> option. 193 194 <p>The rules say cryptographic media should be generated with proventic 195 filestamps, which means the host should already be synchronized before 196 this program is run. 197 This of course creates a chicken-and-egg problem 198 when the host is started for the first time. 199 Accordingly, the host time 200 should be set by some other means, such as eyeball-and-wristwatch, at 201 least so that the certificate lifetime is within the current year. 202 After that and when the host is synchronized to a proventic source, the 203 certificate should be re-generated. 204 205 <p>Additional information on trusted groups and identity schemes is on the 206 Autokey Public-Key Authentication page. 207 208 <div class="node"> 209 <p><hr> 210 <a name="ntp_002dkeygen-Invocation"></a> 211 <br> 212 </div> 213 214 <h3 class="section">Invoking ntp-keygen</h3> 215 216 <p><a name="index-ntp_002dkeygen-1"></a><a name="index-Create-a-NTP-host-key-2"></a> 217 218 <p>This program generates cryptographic data files used by the NTPv4 219 authentication and identification schemes. 220 It generates MD5 key files used in symmetric key cryptography. 221 In addition, if the OpenSSL software library has been installed, 222 it generates keys, certificate and identity files used in public key 223 cryptography. 224 These files are used for cookie encryption, 225 digital signature and challenge/response identification algorithms 226 compatible with the Internet standard security infrastructure. 227 228 <p>All files are in PEM-encoded printable ASCII format, 229 so they can be embedded as MIME attachments in mail to other sites 230 and certificate authorities. 231 By default, files are not encrypted. 232 233 <p>When used to generate message digest keys, the program produces a file 234 containing ten pseudo-random printable ASCII strings suitable for the 235 MD5 message digest algorithm included in the distribution. 236 If the OpenSSL library is installed, it produces an additional ten 237 hex-encoded random bit strings suitable for the SHA1 and other message 238 digest algorithms. 239 The message digest keys file must be distributed and stored 240 using secure means beyond the scope of NTP itself. 241 Besides the keys used for ordinary NTP associations, additional keys 242 can be defined as passwords for the 243 <code>ntpq(1ntpqmdoc)</code> 244 and 245 <code>ntpdc(1ntpdcmdoc)</code> 246 utility programs. 247 248 <p>The remaining generated files are compatible with other OpenSSL 249 applications and other Public Key Infrastructure (PKI) resources. 250 Certificates generated by this program are compatible with extant 251 industry practice, although some users might find the interpretation of 252 X509v3 extension fields somewhat liberal. 253 However, the identity keys are probably not compatible with anything 254 other than Autokey. 255 256 <p>Some files used by this program are encrypted using a private password. 257 The 258 <code>-p</code> 259 option specifies the password for local encrypted files and the 260 <code>-q</code> 261 option the password for encrypted files sent to remote sites. 262 If no password is specified, the host name returned by the Unix 263 <code>gethostname()</code> 264 function, normally the DNS name of the host is used. 265 266 <p>The 267 <kbd>pw</kbd> 268 option of the 269 <kbd>crypto</kbd> 270 configuration command specifies the read 271 password for previously encrypted local files. 272 This must match the local password used by this program. 273 If not specified, the host name is used. 274 Thus, if files are generated by this program without password, 275 they can be read back by 276 <kbd>ntpd</kbd> 277 without password but only on the same host. 278 279 <p>Normally, encrypted files for each host are generated by that host and 280 used only by that host, although exceptions exist as noted later on 281 this page. 282 The symmetric keys file, normally called 283 <kbd>ntp.keys</kbd>, 284 is usually installed in 285 <span class="file">/etc</span>. 286 Other files and links are usually installed in 287 <span class="file">/usr/local/etc</span>, 288 which is normally in a shared filesystem in 289 NFS-mounted networks and cannot be changed by shared clients. 290 The location of the keys directory can be changed by the 291 <kbd>keysdir</kbd> 292 configuration command in such cases. 293 Normally, this is in 294 <span class="file">/etc</span>. 295 296 <p>This program directs commentary and error messages to the standard 297 error stream 298 <kbd>stderr</kbd> 299 and remote files to the standard output stream 300 <kbd>stdout</kbd> 301 where they can be piped to other applications or redirected to files. 302 The names used for generated files and links all begin with the 303 string 304 <kbd>ntpkey</kbd> 305 and include the file type, generating host and filestamp, 306 as described in the 307 Cryptographic Data Files 308 section below. 309 310 <h5 class="subsubsection">Running the Program</h5> 311 312 <p>To test and gain experience with Autokey concepts, log in as root and 313 change to the keys directory, usually 314 <span class="file">/usr/local/etc</span> 315 When run for the first time, or if all files with names beginning with 316 <kbd>ntpkey</kbd> 317 have been removed, use the 318 <code>ntp-keygen</code> 319 command without arguments to generate a 320 default RSA host key and matching RSA-MD5 certificate with expiration 321 date one year hence. 322 If run again without options, the program uses the 323 existing keys and parameters and generates only a new certificate with 324 new expiration date one year hence. 325 326 <p>Run the command on as many hosts as necessary. 327 Designate one of them as the trusted host (TH) using 328 <code>ntp-keygen</code> 329 with the 330 <code>-T</code> 331 option and configure it to synchronize from reliable Internet servers. 332 Then configure the other hosts to synchronize to the TH directly or 333 indirectly. 334 A certificate trail is created when Autokey asks the immediately 335 ascendant host towards the TH to sign its certificate, which is then 336 provided to the immediately descendant host on request. 337 All group hosts should have acyclic certificate trails ending on the TH. 338 339 <p>The host key is used to encrypt the cookie when required and so must be 340 RSA type. 341 By default, the host key is also the sign key used to encrypt 342 signatures. 343 A different sign key can be assigned using the 344 <code>-S</code> 345 option and this can be either RSA or DSA type. 346 By default, the signature 347 message digest type is MD5, but any combination of sign key type and 348 message digest type supported by the OpenSSL library can be specified 349 using the 350 <code>-c</code> 351 option. 352 The rules say cryptographic media should be generated with proventic 353 filestamps, which means the host should already be synchronized before 354 this program is run. 355 This of course creates a chicken-and-egg problem 356 when the host is started for the first time. 357 Accordingly, the host time 358 should be set by some other means, such as eyeball-and-wristwatch, at 359 least so that the certificate lifetime is within the current year. 360 After that and when the host is synchronized to a proventic source, the 361 certificate should be re-generated. 362 363 <p>Additional information on trusted groups and identity schemes is on the 364 Autokey Public-Key Authentication 365 page. 366 367 <p>The 368 <code>ntpd(1ntpdmdoc)</code> 369 configuration command 370 <code>crypto</code> <code>pw</code> <kbd>password</kbd> 371 specifies the read password for previously encrypted files. 372 The daemon expires on the spot if the password is missing 373 or incorrect. 374 For convenience, if a file has been previously encrypted, 375 the default read password is the name of the host running 376 the program. 377 If the previous write password is specified as the host name, 378 these files can be read by that host with no explicit password. 379 380 <p>File names begin with the prefix 381 <code>ntpkey_</code> 382 and end with the postfix 383 <kbd>_hostname.filestamp</kbd>, 384 where 385 <kbd>hostname</kbd> 386 is the owner name, usually the string returned 387 by the Unix gethostname() routine, and 388 <kbd>filestamp</kbd> 389 is the NTP seconds when the file was generated, in decimal digits. 390 This both guarantees uniqueness and simplifies maintenance 391 procedures, since all files can be quickly removed 392 by a 393 <code>rm</code> <code>ntpkey*</code> 394 command or all files generated 395 at a specific time can be removed by a 396 <code>rm</code> 397 <kbd>*filestamp</kbd> 398 command. 399 To further reduce the risk of misconfiguration, 400 the first two lines of a file contain the file name 401 and generation date and time as comments. 402 403 <p>All files are installed by default in the keys directory 404 <span class="file">/usr/local/etc</span>, 405 which is normally in a shared filesystem 406 in NFS-mounted networks. 407 The actual location of the keys directory 408 and each file can be overridden by configuration commands, 409 but this is not recommended. 410 Normally, the files for each host are generated by that host 411 and used only by that host, although exceptions exist 412 as noted later on this page. 413 414 <p>Normally, files containing private values, 415 including the host key, sign key and identification parameters, 416 are permitted root read/write-only; 417 while others containing public values are permitted world readable. 418 Alternatively, files containing private values can be encrypted 419 and these files permitted world readable, 420 which simplifies maintenance in shared file systems. 421 Since uniqueness is insured by the hostname and 422 file name extensions, the files for a NFS server and 423 dependent clients can all be installed in the same shared directory. 424 425 <p>The recommended practice is to keep the file name extensions 426 when installing a file and to install a soft link 427 from the generic names specified elsewhere on this page 428 to the generated files. 429 This allows new file generations to be activated simply 430 by changing the link. 431 If a link is present, ntpd follows it to the file name 432 to extract the filestamp. 433 If a link is not present, 434 <code>ntpd(1ntpdmdoc)</code> 435 extracts the filestamp from the file itself. 436 This allows clients to verify that the file and generation times 437 are always current. 438 The 439 <code>ntp-keygen</code> 440 program uses the same timestamp extension for all files generated 441 at one time, so each generation is distinct and can be readily 442 recognized in monitoring data. 443 444 <h5 class="subsubsection">Running the program</h5> 445 446 <p>The safest way to run the 447 <code>ntp-keygen</code> 448 program is logged in directly as root. 449 The recommended procedure is change to the keys directory, 450 usually 451 <span class="file">/usr/local/etc</span>, 452 then run the program. 453 When run for the first time, 454 or if all 455 <code>ntpkey</code> 456 files have been removed, 457 the program generates a RSA host key file and matching RSA-MD5 certificate file, 458 which is all that is necessary in many cases. 459 The program also generates soft links from the generic names 460 to the respective files. 461 If run again, the program uses the same host key file, 462 but generates a new certificate file and link. 463 464 <p>The host key is used to encrypt the cookie when required and so must be RSA type. 465 By default, the host key is also the sign key used to encrypt signatures. 466 When necessary, a different sign key can be specified and this can be 467 either RSA or DSA type. 468 By default, the message digest type is MD5, but any combination 469 of sign key type and message digest type supported by the OpenSSL library 470 can be specified, including those using the MD2, MD5, SHA, SHA1, MDC2 471 and RIPE160 message digest algorithms. 472 However, the scheme specified in the certificate must be compatible 473 with the sign key. 474 Certificates using any digest algorithm are compatible with RSA sign keys; 475 however, only SHA and SHA1 certificates are compatible with DSA sign keys. 476 477 <p>Private/public key files and certificates are compatible with 478 other OpenSSL applications and very likely other libraries as well. 479 Certificates or certificate requests derived from them should be compatible 480 with extant industry practice, although some users might find 481 the interpretation of X509v3 extension fields somewhat liberal. 482 However, the identification parameter files, although encoded 483 as the other files, are probably not compatible with anything other than Autokey. 484 485 <p>Running the program as other than root and using the Unix 486 <code>su</code> 487 command 488 to assume root may not work properly, since by default the OpenSSL library 489 looks for the random seed file 490 <code>.rnd</code> 491 in the user home directory. 492 However, there should be only one 493 <code>.rnd</code>, 494 most conveniently 495 in the root directory, so it is convenient to define the 496 <code>$RANDFILE</code> 497 environment variable used by the OpenSSL library as the path to 498 <code>/.rnd</code>. 499 500 <p>Installing the keys as root might not work in NFS-mounted 501 shared file systems, as NFS clients may not be able to write 502 to the shared keys directory, even as root. 503 In this case, NFS clients can specify the files in another 504 directory such as 505 <span class="file">/etc</span> 506 using the 507 <code>keysdir</code> 508 command. 509 There is no need for one client to read the keys and certificates 510 of other clients or servers, as these data are obtained automatically 511 by the Autokey protocol. 512 513 <p>Ordinarily, cryptographic files are generated by the host that uses them, 514 but it is possible for a trusted agent (TA) to generate these files 515 for other hosts; however, in such cases files should always be encrypted. 516 The subject name and trusted name default to the hostname 517 of the host generating the files, but can be changed by command line options. 518 It is convenient to designate the owner name and trusted name 519 as the subject and issuer fields, respectively, of the certificate. 520 The owner name is also used for the host and sign key files, 521 while the trusted name is used for the identity files. 522 523 <p>All files are installed by default in the keys directory 524 <span class="file">/usr/local/etc</span>, 525 which is normally in a shared filesystem 526 in NFS-mounted networks. 527 The actual location of the keys directory 528 and each file can be overridden by configuration commands, 529 but this is not recommended. 530 Normally, the files for each host are generated by that host 531 and used only by that host, although exceptions exist 532 as noted later on this page. 533 534 <p>Normally, files containing private values, 535 including the host key, sign key and identification parameters, 536 are permitted root read/write-only; 537 while others containing public values are permitted world readable. 538 Alternatively, files containing private values can be encrypted 539 and these files permitted world readable, 540 which simplifies maintenance in shared file systems. 541 Since uniqueness is insured by the hostname and 542 file name extensions, the files for a NFS server and 543 dependent clients can all be installed in the same shared directory. 544 545 <p>The recommended practice is to keep the file name extensions 546 when installing a file and to install a soft link 547 from the generic names specified elsewhere on this page 548 to the generated files. 549 This allows new file generations to be activated simply 550 by changing the link. 551 If a link is present, ntpd follows it to the file name 552 to extract the filestamp. 553 If a link is not present, 554 <code>ntpd(1ntpdmdoc)</code> 555 extracts the filestamp from the file itself. 556 This allows clients to verify that the file and generation times 557 are always current. 558 The 559 <code>ntp-keygen</code> 560 program uses the same timestamp extension for all files generated 561 at one time, so each generation is distinct and can be readily 562 recognized in monitoring data. 563 564 <h5 class="subsubsection">Running the program</h5> 565 566 <p>The safest way to run the 567 <code>ntp-keygen</code> 568 program is logged in directly as root. 569 The recommended procedure is change to the keys directory, 570 usually 571 <span class="file">/usr/local/etc</span>, 572 then run the program. 573 When run for the first time, 574 or if all 575 <code>ntpkey</code> 576 files have been removed, 577 the program generates a RSA host key file and matching RSA-MD5 certificate file, 578 which is all that is necessary in many cases. 579 The program also generates soft links from the generic names 580 to the respective files. 581 If run again, the program uses the same host key file, 582 but generates a new certificate file and link. 583 584 <p>The host key is used to encrypt the cookie when required and so must be RSA type. 585 By default, the host key is also the sign key used to encrypt signatures. 586 When necessary, a different sign key can be specified and this can be 587 either RSA or DSA type. 588 By default, the message digest type is MD5, but any combination 589 of sign key type and message digest type supported by the OpenSSL library 590 can be specified, including those using the MD2, MD5, SHA, SHA1, MDC2 591 and RIPE160 message digest algorithms. 592 However, the scheme specified in the certificate must be compatible 593 with the sign key. 594 Certificates using any digest algorithm are compatible with RSA sign keys; 595 however, only SHA and SHA1 certificates are compatible with DSA sign keys. 596 597 <p>Private/public key files and certificates are compatible with 598 other OpenSSL applications and very likely other libraries as well. 599 Certificates or certificate requests derived from them should be compatible 600 with extant industry practice, although some users might find 601 the interpretation of X509v3 extension fields somewhat liberal. 602 However, the identification parameter files, although encoded 603 as the other files, are probably not compatible with anything other than Autokey. 604 605 <p>Running the program as other than root and using the Unix 606 <code>su</code> 607 command 608 to assume root may not work properly, since by default the OpenSSL library 609 looks for the random seed file 610 <code>.rnd</code> 611 in the user home directory. 612 However, there should be only one 613 <code>.rnd</code>, 614 most conveniently 615 in the root directory, so it is convenient to define the 616 <code>$RANDFILE</code> 617 environment variable used by the OpenSSL library as the path to 618 <code>/.rnd</code>. 619 620 <p>Installing the keys as root might not work in NFS-mounted 621 shared file systems, as NFS clients may not be able to write 622 to the shared keys directory, even as root. 623 In this case, NFS clients can specify the files in another 624 directory such as 625 <span class="file">/etc</span> 626 using the 627 <code>keysdir</code> 628 command. 629 There is no need for one client to read the keys and certificates 630 of other clients or servers, as these data are obtained automatically 631 by the Autokey protocol. 632 633 <p>Ordinarily, cryptographic files are generated by the host that uses them, 634 but it is possible for a trusted agent (TA) to generate these files 635 for other hosts; however, in such cases files should always be encrypted. 636 The subject name and trusted name default to the hostname 637 of the host generating the files, but can be changed by command line options. 638 It is convenient to designate the owner name and trusted name 639 as the subject and issuer fields, respectively, of the certificate. 640 The owner name is also used for the host and sign key files, 641 while the trusted name is used for the identity files. 642 seconds. 643 seconds. 644 645 <p>s Trusted Hosts and Groups 646 Each cryptographic configuration involves selection of a signature scheme 647 and identification scheme, called a cryptotype, 648 as explained in the 649 <a href="#Authentication-Options">Authentication Options</a> 650 section of 651 <code>ntp.conf(5)</code>. 652 The default cryptotype uses RSA encryption, MD5 message digest 653 and TC identification. 654 First, configure a NTP subnet including one or more low-stratum 655 trusted hosts from which all other hosts derive synchronization 656 directly or indirectly. 657 Trusted hosts have trusted certificates; 658 all other hosts have nontrusted certificates. 659 These hosts will automatically and dynamically build authoritative 660 certificate trails to one or more trusted hosts. 661 A trusted group is the set of all hosts that have, directly or indirectly, 662 a certificate trail ending at a trusted host. 663 The trail is defined by static configuration file entries 664 or dynamic means described on the 665 <a href="#Automatic-NTP-Configuration-Options">Automatic NTP Configuration Options</a> 666 section of 667 <code>ntp.conf(5)</code>. 668 669 <p>On each trusted host as root, change to the keys directory. 670 To insure a fresh fileset, remove all 671 <code>ntpkey</code> 672 files. 673 Then run 674 <code>ntp-keygen</code> 675 <code>-T</code> 676 to generate keys and a trusted certificate. 677 On all other hosts do the same, but leave off the 678 <code>-T</code> 679 flag to generate keys and nontrusted certificates. 680 When complete, start the NTP daemons beginning at the lowest stratum 681 and working up the tree. 682 It may take some time for Autokey to instantiate the certificate trails 683 throughout the subnet, but setting up the environment is completely automatic. 684 685 <p>If it is necessary to use a different sign key or different digest/signature 686 scheme than the default, run 687 <code>ntp-keygen</code> 688 with the 689 <code>-S</code> <kbd>type</kbd> 690 option, where 691 <kbd>type</kbd> 692 is either 693 <code>RSA</code> 694 or 695 <code>DSA</code>. 696 The most often need to do this is when a DSA-signed certificate is used. 697 If it is necessary to use a different certificate scheme than the default, 698 run 699 <code>ntp-keygen</code> 700 with the 701 <code>-c</code> <kbd>scheme</kbd> 702 option and selected 703 <kbd>scheme</kbd> 704 as needed. 705 f 706 <code>ntp-keygen</code> 707 is run again without these options, it generates a new certificate 708 using the same scheme and sign key. 709 710 <p>After setting up the environment it is advisable to update certificates 711 from time to time, if only to extend the validity interval. 712 Simply run 713 <code>ntp-keygen</code> 714 with the same flags as before to generate new certificates 715 using existing keys. 716 However, if the host or sign key is changed, 717 <code>ntpd(1ntpdmdoc)</code> 718 should be restarted. 719 When 720 <code>ntpd(1ntpdmdoc)</code> 721 is restarted, it loads any new files and restarts the protocol. 722 Other dependent hosts will continue as usual until signatures are refreshed, 723 at which time the protocol is restarted. 724 725 <h5 class="subsubsection">Identity Schemes</h5> 726 727 <p>As mentioned on the Autonomous Authentication page, 728 the default TC identity scheme is vulnerable to a middleman attack. 729 However, there are more secure identity schemes available, 730 including PC, IFF, GQ and MV described on the 731 "Identification Schemes" 732 page 733 (maybe available at 734 <code>http://www.eecis.udel.edu/%7emills/keygen.html</code>). 735 These schemes are based on a TA, one or more trusted hosts 736 and some number of nontrusted hosts. 737 Trusted hosts prove identity using values provided by the TA, 738 while the remaining hosts prove identity using values provided 739 by a trusted host and certificate trails that end on that host. 740 The name of a trusted host is also the name of its sugroup 741 and also the subject and issuer name on its trusted certificate. 742 The TA is not necessarily a trusted host in this sense, but often is. 743 744 <p>In some schemes there are separate keys for servers and clients. 745 A server can also be a client of another server, 746 but a client can never be a server for another client. 747 In general, trusted hosts and nontrusted hosts that operate 748 as both server and client have parameter files that contain 749 both server and client keys. 750 Hosts that operate 751 only as clients have key files that contain only client keys. 752 753 <p>The PC scheme supports only one trusted host in the group. 754 On trusted host alice run 755 <code>ntp-keygen</code> 756 <code>-P</code> 757 <code>-p</code> <kbd>password</kbd> 758 to generate the host key file 759 <span class="file">ntpkey_RSAkey_</span><kbd>alice.filestamp</kbd> 760 and trusted private certificate file 761 <span class="file">ntpkey_RSA-MD5_cert_</span><kbd>alice.filestamp</kbd>. 762 Copy both files to all group hosts; 763 they replace the files which would be generated in other schemes. 764 On each host bob install a soft link from the generic name 765 <span class="file">ntpkey_host_</span><kbd>bob</kbd> 766 to the host key file and soft link 767 <span class="file">ntpkey_cert_</span><kbd>bob</kbd> 768 to the private certificate file. 769 Note the generic links are on bob, but point to files generated 770 by trusted host alice. 771 In this scheme it is not possible to refresh 772 either the keys or certificates without copying them 773 to all other hosts in the group. 774 775 <p>For the IFF scheme proceed as in the TC scheme to generate keys 776 and certificates for all group hosts, then for every trusted host in the group, 777 generate the IFF parameter file. 778 On trusted host alice run 779 <code>ntp-keygen</code> 780 <code>-T</code> 781 <code>-I</code> 782 <code>-p</code> <kbd>password</kbd> 783 to produce her parameter file 784 <span class="file">ntpkey_IFFpar_</span><kbd>alice.filestamp</kbd>, 785 which includes both server and client keys. 786 Copy this file to all group hosts that operate as both servers 787 and clients and install a soft link from the generic 788 <span class="file">ntpkey_iff_</span><kbd>alice</kbd> 789 to this file. 790 If there are no hosts restricted to operate only as clients, 791 there is nothing further to do. 792 As the IFF scheme is independent 793 of keys and certificates, these files can be refreshed as needed. 794 795 <p>If a rogue client has the parameter file, it could masquerade 796 as a legitimate server and present a middleman threat. 797 To eliminate this threat, the client keys can be extracted 798 from the parameter file and distributed to all restricted clients. 799 After generating the parameter file, on alice run 800 <code>ntp-keygen</code> 801 <code>-e</code> 802 and pipe the output to a file or mail program. 803 Copy or mail this file to all restricted clients. 804 On these clients install a soft link from the generic 805 <span class="file">ntpkey_iff_</span><kbd>alice</kbd> 806 to this file. 807 To further protect the integrity of the keys, 808 each file can be encrypted with a secret password. 809 810 <p>For the GQ scheme proceed as in the TC scheme to generate keys 811 and certificates for all group hosts, then for every trusted host 812 in the group, generate the IFF parameter file. 813 On trusted host alice run 814 <code>ntp-keygen</code> 815 <code>-T</code> 816 <code>-G</code> 817 <code>-p</code> <kbd>password</kbd> 818 to produce her parameter file 819 <span class="file">ntpkey_GQpar_</span><kbd>alice.filestamp</kbd>, 820 which includes both server and client keys. 821 Copy this file to all group hosts and install a soft link 822 from the generic 823 <span class="file">ntpkey_gq_</span><kbd>alice</kbd> 824 to this file. 825 In addition, on each host bob install a soft link 826 from generic 827 <span class="file">ntpkey_gq_</span><kbd>bob</kbd> 828 to this file. 829 As the GQ scheme updates the GQ parameters file and certificate 830 at the same time, keys and certificates can be regenerated as needed. 831 832 <p>For the MV scheme, proceed as in the TC scheme to generate keys 833 and certificates for all group hosts. 834 For illustration assume trish is the TA, alice one of several trusted hosts 835 and bob one of her clients. 836 On TA trish run 837 <code>ntp-keygen</code> 838 <code>-V</code> <kbd>n</kbd> 839 <code>-p</code> <kbd>password</kbd>, 840 where 841 <kbd>n</kbd> 842 is the number of revokable keys (typically 5) to produce 843 the parameter file 844 <span class="file">ntpkeys_MVpar_</span><kbd>trish.filestamp</kbd> 845 and client key files 846 <span class="file">ntpkeys_MVkeyd_</span><kbd>trish.filestamp</kbd> 847 where 848 <kbd>d</kbd> 849 is the key number (0 < 850 <kbd>d</kbd> 851 < 852 <kbd>n</kbd>). 853 Copy the parameter file to alice and install a soft link 854 from the generic 855 <span class="file">ntpkey_mv_</span><kbd>alice</kbd> 856 to this file. 857 Copy one of the client key files to alice for later distribution 858 to her clients. 859 It doesn't matter which client key file goes to alice, 860 since they all work the same way. 861 Alice copies the client key file to all of her cliens. 862 On client bob install a soft link from generic 863 <span class="file">ntpkey_mvkey_</span><kbd>bob</kbd> 864 to the client key file. 865 As the MV scheme is independent of keys and certificates, 866 these files can be refreshed as needed. 867 868 <h5 class="subsubsection">Command Line Options</h5> 869 870 <dl> 871 <dt><code>-c</code> <kbd>scheme</kbd><dd>Select certificate message digest/signature encryption scheme. 872 The 873 <kbd>scheme</kbd> 874 can be one of the following: 875 . Cm RSA-MD2 , RSA-MD5 , RSA-SHA , RSA-SHA1 , RSA-MDC2 , RSA-RIPEMD160 , DSA-SHA , 876 or 877 <code>DSA-SHA1</code>. 878 Note that RSA schemes must be used with a RSA sign key and DSA 879 schemes must be used with a DSA sign key. 880 The default without this option is 881 <code>RSA-MD5</code>. 882 <br><dt><code>-d</code><dd>Enable debugging. 883 This option displays the cryptographic data produced in eye-friendly billboards. 884 <br><dt><code>-e</code><dd>Write the IFF client keys to the standard output. 885 This is intended for automatic key distribution by mail. 886 <br><dt><code>-G</code><dd>Generate parameters and keys for the GQ identification scheme, 887 obsoleting any that may exist. 888 <br><dt><code>-g</code><dd>Generate keys for the GQ identification scheme 889 using the existing GQ parameters. 890 If the GQ parameters do not yet exist, create them first. 891 <br><dt><code>-H</code><dd>Generate new host keys, obsoleting any that may exist. 892 <br><dt><code>-I</code><dd>Generate parameters for the IFF identification scheme, 893 obsoleting any that may exist. 894 <br><dt><code>-i</code> <kbd>name</kbd><dd>Set the suject name to 895 <kbd>name</kbd>. 896 This is used as the subject field in certificates 897 and in the file name for host and sign keys. 898 <br><dt><code>-M</code><dd>Generate MD5 keys, obsoleting any that may exist. 899 <br><dt><code>-P</code><dd>Generate a private certificate. 900 By default, the program generates public certificates. 901 <br><dt><code>-p</code> <kbd>password</kbd><dd>Encrypt generated files containing private data with 902 <kbd>password</kbd> 903 and the DES-CBC algorithm. 904 <br><dt><code>-q</code><dd>Set the password for reading files to password. 905 <br><dt><code>-S</code> <code>[RSA | DSA]</code><dd>Generate a new sign key of the designated type, 906 obsoleting any that may exist. 907 By default, the program uses the host key as the sign key. 908 <br><dt><code>-s</code> <kbd>name</kbd><dd>Set the issuer name to 909 <kbd>name</kbd>. 910 This is used for the issuer field in certificates 911 and in the file name for identity files. 912 <br><dt><code>-T</code><dd>Generate a trusted certificate. 913 By default, the program generates a non-trusted certificate. 914 <br><dt><code>-V</code> <kbd>nkeys</kbd><dd>Generate parameters and keys for the Mu-Varadharajan (MV) identification scheme. 915 </dl> 916 917 <h5 class="subsubsection">Random Seed File</h5> 918 919 <p>All cryptographically sound key generation schemes must have means 920 to randomize the entropy seed used to initialize 921 the internal pseudo-random number generator used 922 by the library routines. 923 The OpenSSL library uses a designated random seed file for this purpose. 924 The file must be available when starting the NTP daemon and 925 <code>ntp-keygen</code> 926 program. 927 If a site supports OpenSSL or its companion OpenSSH, 928 it is very likely that means to do this are already available. 929 930 <p>It is important to understand that entropy must be evolved 931 for each generation, for otherwise the random number sequence 932 would be predictable. 933 Various means dependent on external events, such as keystroke intervals, 934 can be used to do this and some systems have built-in entropy sources. 935 Suitable means are described in the OpenSSL software documentation, 936 but are outside the scope of this page. 937 938 <p>The entropy seed used by the OpenSSL library is contained in a file, 939 usually called 940 <code>.rnd</code>, 941 which must be available when starting the NTP daemon 942 or the 943 <code>ntp-keygen</code> 944 program. 945 The NTP daemon will first look for the file 946 using the path specified by the 947 <code>randfile</code> 948 subcommand of the 949 <code>crypto</code> 950 configuration command. 951 If not specified in this way, or when starting the 952 <code>ntp-keygen</code> 953 program, 954 the OpenSSL library will look for the file using the path specified 955 by the 956 .Ev RANDFILE 957 environment variable in the user home directory, 958 whether root or some other user. 959 If the 960 .Ev RANDFILE 961 environment variable is not present, 962 the library will look for the 963 <code>.rnd</code> 964 file in the user home directory. 965 If the file is not available or cannot be written, 966 the daemon exits with a message to the system log and the program 967 exits with a suitable error message. 968 969 <h5 class="subsubsection">Cryptographic Data Files</h5> 970 971 <p>All other file formats begin with two lines. 972 The first contains the file name, including the generated host name 973 and filestamp. 974 The second contains the datestamp in conventional Unix date format. 975 Lines beginning with # are considered comments and ignored by the 976 <code>ntp-keygen</code> 977 program and 978 <code>ntpd(1ntpdmdoc)</code> 979 daemon. 980 Cryptographic values are encoded first using ASN.1 rules, 981 then encrypted if necessary, and finally written PEM-encoded 982 printable ASCII format preceded and followed by MIME content identifier lines. 983 984 <p>The format of the symmetric keys file is somewhat different 985 than the other files in the interest of backward compatibility. 986 Since DES-CBC is deprecated in NTPv4, the only key format of interest 987 is MD5 alphanumeric strings. 988 Following hte heard the keys are 989 entered one per line in the format 990 <pre class="example"> <kbd>keyno</kbd> <kbd>type</kbd> <kbd>key</kbd> 991 </pre> 992 <p>where 993 <kbd>keyno</kbd> 994 is a positive integer in the range 1-65,535, 995 <kbd>type</kbd> 996 is the string MD5 defining the key format and 997 <kbd>key</kbd> 998 is the key itself, 999 which is a printable ASCII string 16 characters or less in length. 1000 Each character is chosen from the 93 printable characters 1001 in the range 0x21 through 0x7f excluding space and the 1002 # 1003 character. 1004 1005 <p>Note that the keys used by the 1006 <code>ntpq(1ntpqmdoc)</code> 1007 and 1008 <code>ntpdc(1ntpdcmdoc)</code> 1009 programs 1010 are checked against passwords requested by the programs 1011 and entered by hand, so it is generally appropriate to specify these keys 1012 in human readable ASCII format. 1013 1014 <p>The 1015 <code>ntp-keygen</code> 1016 program generates a MD5 symmetric keys file 1017 <span class="file">ntpkey_MD5key_</span><kbd>hostname.filestamp</kbd>. 1018 Since the file contains private shared keys, 1019 it should be visible only to root and distributed by secure means 1020 to other subnet hosts. 1021 The NTP daemon loads the file 1022 <span class="file">ntp.keys</span>, 1023 so 1024 <code>ntp-keygen</code> 1025 installs a soft link from this name to the generated file. 1026 Subsequently, similar soft links must be installed by manual 1027 or automated means on the other subnet hosts. 1028 While this file is not used with the Autokey Version 2 protocol, 1029 it is needed to authenticate some remote configuration commands 1030 used by the 1031 <code>ntpq(1ntpqmdoc)</code> 1032 and 1033 <code>ntpdc(1ntpdcmdoc)</code> 1034 utilities. 1035 1036 <p>This section was generated by <strong>AutoGen</strong>, 1037 using the <code>agtexi-cmd</code> template and the option descriptions for the <code>ntp-keygen</code> program. 1038 This software is released under the NTP license, <http://ntp.org/license>;. 1039 1040 <ul class="menu"> 1041 <li><a accesskey="1" href="#ntp_002dkeygen-usage">ntp-keygen usage</a>: ntp-keygen help/usage (<span class="option">--help</span>) 1042 <li><a accesskey="2" href="#ntp_002dkeygen-imbits">ntp-keygen imbits</a>: imbits option (-b) 1043 <li><a accesskey="3" href="#ntp_002dkeygen-certificate">ntp-keygen certificate</a>: certificate option (-c) 1044 <li><a accesskey="4" href="#ntp_002dkeygen-cipher">ntp-keygen cipher</a>: cipher option (-C) 1045 <li><a accesskey="5" href="#ntp_002dkeygen-id_002dkey">ntp-keygen id-key</a>: id-key option (-e) 1046 <li><a accesskey="6" href="#ntp_002dkeygen-gq_002dparams">ntp-keygen gq-params</a>: gq-params option (-G) 1047 <li><a accesskey="7" href="#ntp_002dkeygen-host_002dkey">ntp-keygen host-key</a>: host-key option (-H) 1048 <li><a accesskey="8" href="#ntp_002dkeygen-iffkey">ntp-keygen iffkey</a>: iffkey option (-I) 1049 <li><a accesskey="9" href="#ntp_002dkeygen-ident">ntp-keygen ident</a>: ident option (-i) 1050 <li><a href="#ntp_002dkeygen-lifetime">ntp-keygen lifetime</a>: lifetime option (-l) 1051 <li><a href="#ntp_002dkeygen-md5key">ntp-keygen md5key</a>: md5key option (-M) 1052 <li><a href="#ntp_002dkeygen-modulus">ntp-keygen modulus</a>: modulus option (-m) 1053 <li><a href="#ntp_002dkeygen-pvt_002dcert">ntp-keygen pvt-cert</a>: pvt-cert option (-P) 1054 <li><a href="#ntp_002dkeygen-password">ntp-keygen password</a>: password option (-p) 1055 <li><a href="#ntp_002dkeygen-export_002dpasswd">ntp-keygen export-passwd</a>: export-passwd option (-q) 1056 <li><a href="#ntp_002dkeygen-sign_002dkey">ntp-keygen sign-key</a>: sign-key option (-S) 1057 <li><a href="#ntp_002dkeygen-subject_002dname">ntp-keygen subject-name</a>: subject-name option (-s) 1058 <li><a href="#ntp_002dkeygen-trusted_002dcert">ntp-keygen trusted-cert</a>: trusted-cert option (-T) 1059 <li><a href="#ntp_002dkeygen-mv_002dparams">ntp-keygen mv-params</a>: mv-params option (-V) 1060 <li><a href="#ntp_002dkeygen-mv_002dkeys">ntp-keygen mv-keys</a>: mv-keys option (-v) 1061 <li><a href="#ntp_002dkeygen-config">ntp-keygen config</a>: presetting/configuring ntp-keygen 1062 <li><a href="#ntp_002dkeygen-exit-status">ntp-keygen exit status</a>: exit status 1063 <li><a href="#ntp_002dkeygen-Usage">ntp-keygen Usage</a>: Usage 1064 <li><a href="#ntp_002dkeygen-Notes">ntp-keygen Notes</a>: Notes 1065 <li><a href="#ntp_002dkeygen-Bugs">ntp-keygen Bugs</a>: Bugs 1066 </ul> 1067 1068 <div class="node"> 1069 <p><hr> 1070 <a name="ntp_002dkeygen-usage"></a>Next: <a rel="next" accesskey="n" href="#ntp_002dkeygen-imbits">ntp-keygen imbits</a>, 1071 Up: <a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a> 1072 <br> 1073 </div> 1074 1075 <h4 class="subsection">ntp-keygen help/usage (<span class="option">--help</span>)</h4> 1076 1077 <p><a name="index-ntp_002dkeygen-help-3"></a> 1078 This is the automatically generated usage text for ntp-keygen. 1079 1080 <p>The text printed is the same whether selected with the <code>help</code> option 1081 (<span class="option">--help</span>) or the <code>more-help</code> option (<span class="option">--more-help</span>). <code>more-help</code> will print 1082 the usage text by passing it through a pager program. 1083 <code>more-help</code> is disabled on platforms without a working 1084 <code>fork(2)</code> function. The <code>PAGER</code> environment variable is 1085 used to select the program, defaulting to <span class="file">more</span>. Both will exit 1086 with a status code of 0. 1087 1088 <pre class="example">ntp-keygen (ntp) - Create a NTP host key - Ver. 4.2.7p486-RC 1089 Usage: ntp-keygen [ -<flag> [<val>] | --<name>[{=| }<val>] ]... 1090 Flg Arg Option-Name Description 1091 -b Num imbits identity modulus bits 1092 - it must be in the range: 1093 256 to 2048 1094 -c Str certificate certificate scheme 1095 -C Str cipher privatekey cipher 1096 -d no debug-level Increase debug verbosity level 1097 - may appear multiple times 1098 -D Num set-debug-level Set the debug verbosity level 1099 - may appear multiple times 1100 -e no id-key Write IFF or GQ identity keys 1101 -G no gq-params Generate GQ parameters and keys 1102 -H no host-key generate RSA host key 1103 -I no iffkey generate IFF parameters 1104 -i Str ident set Autokey group name 1105 -l Num lifetime set certificate lifetime 1106 -M no md5key generate MD5 keys 1107 -m Num modulus modulus 1108 - it must be in the range: 1109 256 to 2048 1110 -P no pvt-cert generate PC private certificate 1111 -p Str password local private password 1112 -q Str export-passwd export IFF or GQ group keys with password 1113 -S Str sign-key generate sign key (RSA or DSA) 1114 -s Str subject-name set host and optionally group name 1115 -T no trusted-cert trusted certificate (TC scheme) 1116 -V Num mv-params generate <num> MV parameters 1117 -v Num mv-keys update <num> MV keys 1118 opt version output version information and exit 1119 -? no help display extended usage information and exit 1120 -! no more-help extended usage information passed thru pager 1121 -> opt save-opts save the option state to a config file 1122 -< Str load-opts load options from a config file 1123 - disabled as '--no-load-opts' 1124 - may appear multiple times 1125 1126 Options are specified by doubled hyphens and their name or by a single 1127 hyphen and the flag character. 1128 1129 1130 The following option preset mechanisms are supported: 1131 - reading file $HOME/.ntprc 1132 - reading file ./.ntprc 1133 - examining environment variables named NTP_KEYGEN_* 1134 1135 Please send bug reports to: <http://bugs.ntp.org, bugs (a] ntp.org> 1136 </pre> 1137 <div class="node"> 1138 <p><hr> 1139 <a name="ntp_002dkeygen-imbits"></a>Next: <a rel="next" accesskey="n" href="#ntp_002dkeygen-certificate">ntp-keygen certificate</a>, 1140 Previous: <a rel="previous" accesskey="p" href="#ntp_002dkeygen-usage">ntp-keygen usage</a>, 1141 Up: <a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a> 1142 <br> 1143 </div> 1144 1145 <h4 class="subsection">imbits option (-b)</h4> 1146 1147 <p><a name="index-ntp_002dkeygen_002dimbits-4"></a> 1148 This is the “identity modulus bits” option. 1149 This option takes a number argument <span class="file">imbits</span>. 1150 1151 <p class="noindent">This option has some usage constraints. It: 1152 <ul> 1153 <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 1154 </ul> 1155 1156 <p>The number of bits in the identity modulus. The default is 256. 1157 <div class="node"> 1158 <p><hr> 1159 <a name="ntp_002dkeygen-certificate"></a>Next: <a rel="next" accesskey="n" href="#ntp_002dkeygen-cipher">ntp-keygen cipher</a>, 1160 Previous: <a rel="previous" accesskey="p" href="#ntp_002dkeygen-imbits">ntp-keygen imbits</a>, 1161 Up: <a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a> 1162 <br> 1163 </div> 1164 1165 <h4 class="subsection">certificate option (-c)</h4> 1166 1167 <p><a name="index-ntp_002dkeygen_002dcertificate-5"></a> 1168 This is the “certificate scheme” option. 1169 This option takes a string argument <span class="file">scheme</span>. 1170 1171 <p class="noindent">This option has some usage constraints. It: 1172 <ul> 1173 <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 1174 </ul> 1175 1176 <p>scheme is one of 1177 RSA-MD2, RSA-MD5, RSA-SHA, RSA-SHA1, RSA-MDC2, RSA-RIPEMD160, 1178 DSA-SHA, or DSA-SHA1. 1179 1180 <p>Select the certificate message digest/signature encryption scheme. 1181 Note that RSA schemes must be used with a RSA sign key and DSA 1182 schemes must be used with a DSA sign key. The default without 1183 this option is RSA-MD5. 1184 <div class="node"> 1185 <p><hr> 1186 <a name="ntp_002dkeygen-cipher"></a>Next: <a rel="next" accesskey="n" href="#ntp_002dkeygen-id_002dkey">ntp-keygen id-key</a>, 1187 Previous: <a rel="previous" accesskey="p" href="#ntp_002dkeygen-certificate">ntp-keygen certificate</a>, 1188 Up: <a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a> 1189 <br> 1190 </div> 1191 1192 <h4 class="subsection">cipher option (-C)</h4> 1193 1194 <p><a name="index-ntp_002dkeygen_002dcipher-6"></a> 1195 This is the “privatekey cipher” option. 1196 This option takes a string argument <span class="file">cipher</span>. 1197 1198 <p class="noindent">This option has some usage constraints. It: 1199 <ul> 1200 <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 1201 </ul> 1202 1203 <p>Select the cipher which is used to encrypt the files containing 1204 private keys. The default is three-key triple DES in CBC mode, 1205 equivalent to "<code>-C des-ede3-cbc". The openssl tool lists ciphers 1206 available in "openssl -h" output. 1207 </code><div class="node"> 1208 <p><hr> 1209 <a name="ntp_002dkeygen-id_002dkey"></a>Next: <a rel="next" accesskey="n" href="#ntp_002dkeygen-gq_002dparams">ntp-keygen gq-params</a>, 1210 Previous: <a rel="previous" accesskey="p" href="#ntp_002dkeygen-cipher">ntp-keygen cipher</a>, 1211 Up: <a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a> 1212 <br> 1213 </div> 1214 1215 <h4 class="subsection">id-key option (-e)</h4> 1216 1217 <p><a name="index-ntp_002dkeygen_002did_002dkey-7"></a> 1218 This is the “write iff or gq identity keys” option. 1219 1220 <p class="noindent">This option has some usage constraints. It: 1221 <ul> 1222 <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 1223 </ul> 1224 1225 <p>Write the IFF or GQ client keys to the standard output. This is 1226 intended for automatic key distribution by mail. 1227 <div class="node"> 1228 <p><hr> 1229 <a name="ntp_002dkeygen-gq_002dparams"></a>Next: <a rel="next" accesskey="n" href="#ntp_002dkeygen-host_002dkey">ntp-keygen host-key</a>, 1230 Previous: <a rel="previous" accesskey="p" href="#ntp_002dkeygen-id_002dkey">ntp-keygen id-key</a>, 1231 Up: <a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a> 1232 <br> 1233 </div> 1234 1235 <h4 class="subsection">gq-params option (-G)</h4> 1236 1237 <p><a name="index-ntp_002dkeygen_002dgq_002dparams-8"></a> 1238 This is the “generate gq parameters and keys” option. 1239 1240 <p class="noindent">This option has some usage constraints. It: 1241 <ul> 1242 <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 1243 </ul> 1244 1245 <p>Generate parameters and keys for the GQ identification scheme, 1246 obsoleting any that may exist. 1247 <div class="node"> 1248 <p><hr> 1249 <a name="ntp_002dkeygen-host_002dkey"></a>Next: <a rel="next" accesskey="n" href="#ntp_002dkeygen-iffkey">ntp-keygen iffkey</a>, 1250 Previous: <a rel="previous" accesskey="p" href="#ntp_002dkeygen-gq_002dparams">ntp-keygen gq-params</a>, 1251 Up: <a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a> 1252 <br> 1253 </div> 1254 1255 <h4 class="subsection">host-key option (-H)</h4> 1256 1257 <p><a name="index-ntp_002dkeygen_002dhost_002dkey-9"></a> 1258 This is the “generate rsa host key” option. 1259 1260 <p class="noindent">This option has some usage constraints. It: 1261 <ul> 1262 <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 1263 </ul> 1264 1265 <p>Generate new host keys, obsoleting any that may exist. 1266 <div class="node"> 1267 <p><hr> 1268 <a name="ntp_002dkeygen-iffkey"></a>Next: <a rel="next" accesskey="n" href="#ntp_002dkeygen-ident">ntp-keygen ident</a>, 1269 Previous: <a rel="previous" accesskey="p" href="#ntp_002dkeygen-host_002dkey">ntp-keygen host-key</a>, 1270 Up: <a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a> 1271 <br> 1272 </div> 1273 1274 <h4 class="subsection">iffkey option (-I)</h4> 1275 1276 <p><a name="index-ntp_002dkeygen_002diffkey-10"></a> 1277 This is the “generate iff parameters” option. 1278 1279 <p class="noindent">This option has some usage constraints. It: 1280 <ul> 1281 <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 1282 </ul> 1283 1284 <p>Generate parameters for the IFF identification scheme, obsoleting 1285 any that may exist. 1286 <div class="node"> 1287 <p><hr> 1288 <a name="ntp_002dkeygen-ident"></a>Next: <a rel="next" accesskey="n" href="#ntp_002dkeygen-lifetime">ntp-keygen lifetime</a>, 1289 Previous: <a rel="previous" accesskey="p" href="#ntp_002dkeygen-iffkey">ntp-keygen iffkey</a>, 1290 Up: <a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a> 1291 <br> 1292 </div> 1293 1294 <h4 class="subsection">ident option (-i)</h4> 1295 1296 <p><a name="index-ntp_002dkeygen_002dident-11"></a> 1297 This is the “set autokey group name” option. 1298 This option takes a string argument <span class="file">group</span>. 1299 1300 <p class="noindent">This option has some usage constraints. It: 1301 <ul> 1302 <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 1303 </ul> 1304 1305 <p>Set the optional Autokey group name to name. This is used in 1306 the file name of IFF, GQ, and MV client parameters files. In 1307 that role, the default is the host name if this option is not 1308 provided. The group name, if specified using <code>-i/--ident</code> or 1309 using <code>-s/--subject-name</code> following an '<code>}' character, 1310 is also a part of the self-signed host certificate's subject and 1311 issuer names in the form host 1312 <p>'crypto ident' or 'server ident' configuration in 1313 ntpd's configuration file. 1314 </code><div class="node"> 1315 <p><hr> 1316 <a name="ntp_002dkeygen-lifetime"></a>Next: <a rel="next" accesskey="n" href="#ntp_002dkeygen-md5key">ntp-keygen md5key</a>, 1317 Previous: <a rel="previous" accesskey="p" href="#ntp_002dkeygen-ident">ntp-keygen ident</a>, 1318 Up: <a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a> 1319 <br> 1320 </div> 1321 1322 <h4 class="subsection">lifetime option (-l)</h4> 1323 1324 <p><a name="index-ntp_002dkeygen_002dlifetime-12"></a> 1325 This is the ``set certificate lifetime'' option. 1326 This option takes a number argument <span class="file">lifetime</span>. 1327 1328 <p class="noindent">This option has some usage constraints. It: 1329 <ul> 1330 <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 1331 </ul> 1332 1333 <p>Set the certificate expiration to lifetime days from now. 1334 <div class="node"> 1335 <p><hr> 1336 <a name="ntp_002dkeygen-md5key"></a>Next: <a rel="next" accesskey="n" href="#ntp_002dkeygen-modulus">ntp-keygen modulus</a>, 1337 Previous: <a rel="previous" accesskey="p" href="#ntp_002dkeygen-lifetime">ntp-keygen lifetime</a>, 1338 Up: <a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a> 1339 <br> 1340 </div> 1341 1342 <h4 class="subsection">md5key option (-M)</h4> 1343 1344 <p><a name="index-ntp_002dkeygen_002dmd5key-13"></a> 1345 This is the ``generate md5 keys'' option. 1346 Generate MD5 keys, obsoleting any that may exist. 1347 <div class="node"> 1348 <p><hr> 1349 <a name="ntp_002dkeygen-modulus"></a>Next: <a rel="next" accesskey="n" href="#ntp_002dkeygen-pvt_002dcert">ntp-keygen pvt-cert</a>, 1350 Previous: <a rel="previous" accesskey="p" href="#ntp_002dkeygen-md5key">ntp-keygen md5key</a>, 1351 Up: <a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a> 1352 <br> 1353 </div> 1354 1355 <h4 class="subsection">modulus option (-m)</h4> 1356 1357 <p><a name="index-ntp_002dkeygen_002dmodulus-14"></a> 1358 This is the ``modulus'' option. 1359 This option takes a number argument <span class="file">modulus</span>. 1360 1361 <p class="noindent">This option has some usage constraints. It: 1362 <ul> 1363 <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 1364 </ul> 1365 1366 <p>The number of bits in the prime modulus. The default is 512. 1367 <div class="node"> 1368 <p><hr> 1369 <a name="ntp_002dkeygen-pvt_002dcert"></a>Next: <a rel="next" accesskey="n" href="#ntp_002dkeygen-password">ntp-keygen password</a>, 1370 Previous: <a rel="previous" accesskey="p" href="#ntp_002dkeygen-modulus">ntp-keygen modulus</a>, 1371 Up: <a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a> 1372 <br> 1373 </div> 1374 1375 <h4 class="subsection">pvt-cert option (-P)</h4> 1376 1377 <p><a name="index-ntp_002dkeygen_002dpvt_002dcert-15"></a> 1378 This is the ``generate pc private certificate'' option. 1379 1380 <p class="noindent">This option has some usage constraints. It: 1381 <ul> 1382 <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 1383 </ul> 1384 1385 <p>Generate a private certificate. By default, the program generates 1386 public certificates. 1387 <div class="node"> 1388 <p><hr> 1389 <a name="ntp_002dkeygen-password"></a>Next: <a rel="next" accesskey="n" href="#ntp_002dkeygen-export_002dpasswd">ntp-keygen export-passwd</a>, 1390 Previous: <a rel="previous" accesskey="p" href="#ntp_002dkeygen-pvt_002dcert">ntp-keygen pvt-cert</a>, 1391 Up: <a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a> 1392 <br> 1393 </div> 1394 1395 <h4 class="subsection">password option (-p)</h4> 1396 1397 <p><a name="index-ntp_002dkeygen_002dpassword-16"></a> 1398 This is the ``local private password'' option. 1399 This option takes a string argument <span class="file">passwd</span>. 1400 1401 <p class="noindent">This option has some usage constraints. It: 1402 <ul> 1403 <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 1404 </ul> 1405 1406 <p>Local files containing private data are encrypted with the 1407 DES-CBC algorithm and the specified password. The same password 1408 must be specified to the local ntpd via the "crypto pw password" 1409 configuration command. The default password is the local 1410 hostname. 1411 <div class="node"> 1412 <p><hr> 1413 <a name="ntp_002dkeygen-export_002dpasswd"></a>Next: <a rel="next" accesskey="n" href="#ntp_002dkeygen-sign_002dkey">ntp-keygen sign-key</a>, 1414 Previous: <a rel="previous" accesskey="p" href="#ntp_002dkeygen-password">ntp-keygen password</a>, 1415 Up: <a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a> 1416 <br> 1417 </div> 1418 1419 <h4 class="subsection">export-passwd option (-q)</h4> 1420 1421 <p><a name="index-ntp_002dkeygen_002dexport_002dpasswd-17"></a> 1422 This is the ``export iff or gq group keys with password'' option. 1423 This option takes a string argument <span class="file">passwd</span>. 1424 1425 <p class="noindent">This option has some usage constraints. It: 1426 <ul> 1427 <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 1428 </ul> 1429 1430 <p>Export IFF or GQ identity group keys to the standard output, 1431 encrypted with the DES-CBC algorithm and the specified password. 1432 The same password must be specified to the remote ntpd via the 1433 "crypto pw password" configuration command. See also the option 1434 --id-key (-e) for unencrypted exports. 1435 <div class="node"> 1436 <p><hr> 1437 <a name="ntp_002dkeygen-sign_002dkey"></a>Next: <a rel="next" accesskey="n" href="#ntp_002dkeygen-subject_002dname">ntp-keygen subject-name</a>, 1438 Previous: <a rel="previous" accesskey="p" href="#ntp_002dkeygen-export_002dpasswd">ntp-keygen export-passwd</a>, 1439 Up: <a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a> 1440 <br> 1441 </div> 1442 1443 <h4 class="subsection">sign-key option (-S)</h4> 1444 1445 <p><a name="index-ntp_002dkeygen_002dsign_002dkey-18"></a> 1446 This is the ``generate sign key (rsa or dsa)'' option. 1447 This option takes a string argument <span class="file">sign</span>. 1448 1449 <p class="noindent">This option has some usage constraints. It: 1450 <ul> 1451 <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 1452 </ul> 1453 1454 <p>Generate a new sign key of the designated type, obsoleting any 1455 that may exist. By default, the program uses the host key as the 1456 sign key. 1457 <div class="node"> 1458 <p><hr> 1459 <a name="ntp_002dkeygen-subject_002dname"></a>Next: <a rel="next" accesskey="n" href="#ntp_002dkeygen-trusted_002dcert">ntp-keygen trusted-cert</a>, 1460 Previous: <a rel="previous" accesskey="p" href="#ntp_002dkeygen-sign_002dkey">ntp-keygen sign-key</a>, 1461 Up: <a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a> 1462 <br> 1463 </div> 1464 1465 <h4 class="subsection">subject-name option (-s)</h4> 1466 1467 <p><a name="index-ntp_002dkeygen_002dsubject_002dname-19"></a> 1468 This is the ``set host and optionally group name'' option. 1469 This option takes a string argument <span class="file">host@group</span>. 1470 1471 <p class="noindent">This option has some usage constraints. It: 1472 <ul> 1473 <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 1474 </ul> 1475 1476 <p>Set the Autokey host name, and optionally, group name specified 1477 following an '<code>}' character. The host name is used in the file 1478 name of generated host and signing certificates, without the 1479 group name. The host name, and if provided, group name are used 1480 in host 1481 <p>fields. Specifying '-s 1482 <p>leaving the host name unchanged while appending 1483 <p>subject and issuer fields, as with -i group. The group name, or 1484 if not provided, the host name are also used in the file names 1485 of IFF, GQ, and MV client parameter files. 1486 </code><div class="node"> 1487 <p><hr> 1488 <a name="ntp_002dkeygen-trusted_002dcert"></a>Next: <a rel="next" accesskey="n" href="#ntp_002dkeygen-mv_002dparams">ntp-keygen mv-params</a>, 1489 Previous: <a rel="previous" accesskey="p" href="#ntp_002dkeygen-subject_002dname">ntp-keygen subject-name</a>, 1490 Up: <a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a> 1491 <br> 1492 </div> 1493 1494 <h4 class="subsection">trusted-cert option (-T)</h4> 1495 1496 <p><a name="index-ntp_002dkeygen_002dtrusted_002dcert-20"></a> 1497 This is the ``trusted certificate (tc scheme)'' option. 1498 1499 <p class="noindent">This option has some usage constraints. It: 1500 <ul> 1501 <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 1502 </ul> 1503 1504 <p>Generate a trusted certificate. By default, the program generates 1505 a non-trusted certificate. 1506 <div class="node"> 1507 <p><hr> 1508 <a name="ntp_002dkeygen-mv_002dparams"></a>Next: <a rel="next" accesskey="n" href="#ntp_002dkeygen-mv_002dkeys">ntp-keygen mv-keys</a>, 1509 Previous: <a rel="previous" accesskey="p" href="#ntp_002dkeygen-trusted_002dcert">ntp-keygen trusted-cert</a>, 1510 Up: <a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a> 1511 <br> 1512 </div> 1513 1514 <h4 class="subsection">mv-params option (-V)</h4> 1515 1516 <p><a name="index-ntp_002dkeygen_002dmv_002dparams-21"></a> 1517 This is the ``generate <num> mv parameters'' option. 1518 This option takes a number argument <span class="file">num</span>. 1519 1520 <p class="noindent">This option has some usage constraints. It: 1521 <ul> 1522 <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 1523 </ul> 1524 1525 <p>Generate parameters and keys for the Mu-Varadharajan (MV) 1526 identification scheme. 1527 <div class="node"> 1528 <p><hr> 1529 <a name="ntp_002dkeygen-mv_002dkeys"></a>Next: <a rel="next" accesskey="n" href="#ntp_002dkeygen-config">ntp-keygen config</a>, 1530 Previous: <a rel="previous" accesskey="p" href="#ntp_002dkeygen-mv_002dparams">ntp-keygen mv-params</a>, 1531 Up: <a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a> 1532 <br> 1533 </div> 1534 1535 <h4 class="subsection">mv-keys option (-v)</h4> 1536 1537 <p><a name="index-ntp_002dkeygen_002dmv_002dkeys-22"></a> 1538 This is the ``update <num> mv keys'' option. 1539 This option takes a number argument <span class="file">num</span>. 1540 1541 <p class="noindent">This option has some usage constraints. It: 1542 <ul> 1543 <li>must be compiled in by defining <code>AUTOKEY</code> during the compilation. 1544 </ul> 1545 1546 <p>This option has no <span class="samp">doc</span> documentation. 1547 1548 <div class="node"> 1549 <p><hr> 1550 <a name="ntp_002dkeygen-config"></a>Next: <a rel="next" accesskey="n" href="#ntp_002dkeygen-exit-status">ntp-keygen exit status</a>, 1551 Previous: <a rel="previous" accesskey="p" href="#ntp_002dkeygen-mv_002dkeys">ntp-keygen mv-keys</a>, 1552 Up: <a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a> 1553 <br> 1554 </div> 1555 1556 <h4 class="subsection">presetting/configuring ntp-keygen</h4> 1557 1558 <p>Any option that is not marked as <i>not presettable</i> may be preset by 1559 loading values from configuration ("rc" or "ini") files, and values from environment variables named <code>NTP-KEYGEN</code> and <code>NTP-KEYGEN_<OPTION_NAME></code>. <code><OPTION_NAME></code> must be one of 1560 the options listed above in upper case and segmented with underscores. 1561 The <code>NTP-KEYGEN</code> variable will be tokenized and parsed like 1562 the command line. The remaining variables are tested for existence and their 1563 values are treated like option arguments. 1564 1565 <p class="noindent"><code>libopts</code> will search in 2 places for configuration files: 1566 <ul> 1567 <li>$HOME 1568 <li>$PWD 1569 </ul> 1570 The environment variables <code>HOME</code>, and <code>PWD</code> 1571 are expanded and replaced when <span class="file">ntp-keygen</span> runs. 1572 For any of these that are plain files, they are simply processed. 1573 For any that are directories, then a file named <span class="file">.ntprc</span> is searched for 1574 within that directory and processed. 1575 1576 <p>Configuration files may be in a wide variety of formats. 1577 The basic format is an option name followed by a value (argument) on the 1578 same line. Values may be separated from the option name with a colon, 1579 equal sign or simply white space. Values may be continued across multiple 1580 lines by escaping the newline with a backslash. 1581 1582 <p>Multiple programs may also share the same initialization file. 1583 Common options are collected at the top, followed by program specific 1584 segments. The segments are separated by lines like: 1585 <pre class="example"> [NTP-KEYGEN] 1586 </pre> 1587 <p class="noindent">or by 1588 <pre class="example"> <?program ntp-keygen> 1589 </pre> 1590 <p class="noindent">Do not mix these styles within one configuration file. 1591 1592 <p>Compound values and carefully constructed string values may also be 1593 specified using XML syntax: 1594 <pre class="example"> <option-name> 1595 <sub-opt>...&lt;...&gt;...</sub-opt> 1596 </option-name> 1597 </pre> 1598 <p class="noindent">yielding an <code>option-name.sub-opt</code> string value of 1599 <pre class="example"> "...<...>..." 1600 </pre> 1601 <p><code>AutoOpts</code> does not track suboptions. You simply note that it is a 1602 hierarchicly valued option. <code>AutoOpts</code> does provide a means for searching 1603 the associated name/value pair list (see: optionFindValue). 1604 1605 <p>The command line options relating to configuration and/or usage help are: 1606 1607 <h5 class="subsubheading">version (-)</h5> 1608 1609 <p>Print the program version to standard out, optionally with licensing 1610 information, then exit 0. The optional argument specifies how much licensing 1611 detail to provide. The default is to print just the version. The licensing infomation may be selected with an option argument. 1612 Only the first letter of the argument is examined: 1613 1614 <dl> 1615 <dt><span class="samp">version</span><dd>Only print the version. This is the default. 1616 <br><dt><span class="samp">copyright</span><dd>Name the copyright usage licensing terms. 1617 <br><dt><span class="samp">verbose</span><dd>Print the full copyright usage licensing terms. 1618 </dl> 1619 1620 <div class="node"> 1621 <p><hr> 1622 <a name="ntp_002dkeygen-exit-status"></a>Next: <a rel="next" accesskey="n" href="#ntp_002dkeygen-Usage">ntp-keygen Usage</a>, 1623 Previous: <a rel="previous" accesskey="p" href="#ntp_002dkeygen-config">ntp-keygen config</a>, 1624 Up: <a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a> 1625 <br> 1626 </div> 1627 1628 <h4 class="subsection">ntp-keygen exit status</h4> 1629 1630 <p>One of the following exit values will be returned: 1631 <dl> 1632 <dt><span class="samp">0 (EXIT_SUCCESS)</span><dd>Successful program execution. 1633 <br><dt><span class="samp">1 (EXIT_FAILURE)</span><dd>The operation failed or the command syntax was not valid. 1634 <br><dt><span class="samp">66 (EX_NOINPUT)</span><dd>A specified configuration file could not be loaded. 1635 <br><dt><span class="samp">70 (EX_SOFTWARE)</span><dd>libopts had an internal operational error. Please report 1636 it to autogen-users (a] lists.sourceforge.net. Thank you. 1637 </dl> 1638 <div class="node"> 1639 <p><hr> 1640 <a name="ntp_002dkeygen-Usage"></a>Next: <a rel="next" accesskey="n" href="#ntp_002dkeygen-Notes">ntp-keygen Notes</a>, 1641 Previous: <a rel="previous" accesskey="p" href="#ntp_002dkeygen-exit-status">ntp-keygen exit status</a>, 1642 Up: <a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a> 1643 <br> 1644 </div> 1645 1646 <h4 class="subsection">ntp-keygen Usage</h4> 1647 1648 <div class="node"> 1649 <p><hr> 1650 <a name="ntp_002dkeygen-Notes"></a>Next: <a rel="next" accesskey="n" href="#ntp_002dkeygen-Bugs">ntp-keygen Bugs</a>, 1651 Previous: <a rel="previous" accesskey="p" href="#ntp_002dkeygen-Usage">ntp-keygen Usage</a>, 1652 Up: <a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a> 1653 <br> 1654 </div> 1655 1656 <h4 class="subsection">ntp-keygen Notes</h4> 1657 1658 <div class="node"> 1659 <p><hr> 1660 <a name="ntp_002dkeygen-Bugs"></a>Previous: <a rel="previous" accesskey="p" href="#ntp_002dkeygen-Notes">ntp-keygen Notes</a>, 1661 Up: <a rel="up" accesskey="u" href="#ntp_002dkeygen-Invocation">ntp-keygen Invocation</a> 1662 <br> 1663 </div> 1664 1665 <h4 class="subsection">ntp-keygen Bugs</h4> 1666 1667 <div class="node"> 1668 <p><hr> 1669 <a name="Random-Seed-File"></a>Next: <a rel="next" accesskey="n" href="#Cryptographic-Data-Files">Cryptographic Data Files</a>, 1670 Previous: <a rel="previous" accesskey="p" href="#Running-the-Program">Running the Program</a>, 1671 Up: <a rel="up" accesskey="u" href="#Top">Top</a> 1672 <br> 1673 </div> 1674 1675 <!-- node-name, next, previous, up --> 1676 <h3 class="section">Random Seed File</h3> 1677 1678 <p>All cryptographically sound key generation schemes must have means to 1679 randomize the entropy seed used to initialize the internal 1680 pseudo-random number generator used by the OpenSSL library routines. 1681 If a site supports ssh, it is very likely that means to do this are 1682 already available. 1683 The entropy seed used by the OpenSSL library is contained in a file, 1684 usually called <code>.rnd</code>, which must be available when 1685 starting the <code>ntp-keygen</code> program or <code>ntpd</code> daemon. 1686 1687 <p>The OpenSSL library looks for the file using the path specified by the 1688 <code>RANDFILE</code> environment variable in the user home directory, whether root 1689 or some other user. 1690 If the <code>RANDFILE</code> environment variable is not 1691 present, the library looks for the <code>.rnd</code> file in the user home 1692 directory. 1693 Since both the <code>ntp-keygen</code> program and <code>ntpd</code> daemon must run 1694 as root, the logical place to put this file is in <code>/.rnd</code> or 1695 <code>/root/.rnd</code>. 1696 If the file is not available or cannot be written, the program exits 1697 with a message to the system log. 1698 1699 <div class="node"> 1700 <p><hr> 1701 <a name="Cryptographic-Data-Files"></a>Previous: <a rel="previous" accesskey="p" href="#Random-Seed-File">Random Seed File</a>, 1702 Up: <a rel="up" accesskey="u" href="#Top">Top</a> 1703 <br> 1704 </div> 1705 1706 <!-- node-name, next, previous, up --> 1707 <h3 class="section">Cryptographic Data Files</h3> 1708 1709 <p>File and link names are in the <code>form ntpkey_key_name.fstamp</code>, 1710 where <code>key</code> is the key or parameter type, 1711 <code>name</code> is the host or group name and 1712 <code>fstamp</code> is the filestamp (NTP seconds) when the file was created). 1713 By convention, key names in generated file names include both upper and 1714 lower case characters, while key names in generated link names include 1715 only lower case characters. The filestamp is not used in generated link 1716 names. 1717 1718 <p>The key name is a string defining the cryptographic key type. 1719 Key types include public/private keys host and sign, certificate cert 1720 and several challenge/response key types. 1721 By convention, client files used for 1722 challenges have a par subtype, as in the IFF challenge IFFpar, while 1723 server files for responses have a key subtype, as in the GQ response 1724 GQkey. 1725 1726 <p>All files begin with two nonencrypted lines. The first line contains 1727 the file name in the format <code>ntpkey_key_host.fstamp</code>. 1728 The second line contains the datestamp in conventional Unix date format. 1729 Lines beginning with <code>#</code> are ignored. 1730 1731 <p>The remainder of the file contains cryptographic data encoded first 1732 using ASN.1 rules, then encrypted using the DES-CBC algorithm with 1733 given password and finally written in PEM-encoded printable ASCII text 1734 preceded and followed by MIME content identifier lines. 1735 1736 <p>The format of the symmetric keys file, ordinarily named <code>ntp.keys</code>, 1737 is somewhat different than the other files in the interest of backward 1738 compatibility. 1739 Ordinarily, the file is generated by this program, but 1740 it can be constructed and edited using an ordinary text editor. 1741 1742 <pre class="example"> # ntpkey_MD5key_hms.local.3564038757 1743 # Sun Dec 9 02:45:57 2012 1744 1745 1 MD5 "]!ghT%O;3)WJ,/Nc:>I # MD5 key 1746 2 MD5 lu+H^tF46BKR-6~pV_5 # MD5 key 1747 3 MD5 :lnoVsE%Yz*avh%EtNC # MD5 key 1748 4 MD5 |fdZrf0sF~^V # MD5 key 1749 5 MD5 IyAG>O"y"LmCRS!*bHC # MD5 key 1750 6 MD5 ">e\A # MD5 key 1751 7 MD5 c9x=M'CfLxax9v)PV-si # MD5 key 1752 8 MD5 E|=jvFVov?Bn|Ev=&aK\ # MD5 key 1753 9 MD5 T!c4UT&`(m$+m+B6,`Q0 # MD5 key 1754 10 MD5 JVF/1=)=IFbHbJQz..Cd # MD5 key 1755 11 SHA1 6dea311109529e436c2b4fccae9bc753c16d1b48 # SHA1 key 1756 12 SHA1 7076f373d86c4848c59ff8046e49cb7d614ec394 # SHA1 key 1757 13 SHA1 5f48b1b60591eb01b7cf1d33b7774f08d20262d3 # SHA1 key 1758 14 SHA1 eed5ab9d9497319ec60cf3781d52607e76720178 # SHA1 key 1759 15 SHA1 f283562611a04c964da8126296f5f8e58c3f85de # SHA1 key 1760 16 SHA1 1930da171297dd63549af50b29449de17dcf341f # SHA1 key 1761 17 SHA1 fee892110358cd4382322b889869e750db8e8a8f # SHA1 key 1762 18 SHA1 b5520c9fadd7ad3fd8bfa061c8821b65d029bb37 # SHA1 key 1763 19 SHA1 8c74fb440ec80f453ec6aaa62b9baed0ab723b92 # SHA1 key 1764 20 SHA1 6bc05f734306a189326000970c19b3910f403795 # SHA1 key 1765 </pre> 1766 <p>Figure 1. Typical Symmetric Key File 1767 1768 <p>Figure 1 shows a typical symmetric keys file used by the reference 1769 implementation. 1770 Each line of the file contains three fields, first an 1771 integer between 1 and 65534, inclusive, representing the key identifier 1772 used in the server and peer configuration commands. 1773 Next is the key type for the message digest algorithm, 1774 which in the absence of the 1775 OpenSSL library must be MD5 to designate the MD5 message digest 1776 algorithm. 1777 If the OpenSSL library is installed, the key type can be any 1778 message digest algorithm supported by that library. 1779 However, if 1780 compatibility with FIPS 140-2 is required, the key type must be either 1781 SHA or SHA1. 1782 The key type can be changed using an ASCII text editor. 1783 1784 <p>An MD5 key consists of a printable ASCII string less than or equal to 1785 16 characters and terminated by whitespace or a # character. 1786 An OpenSSL 1787 key consists of a hex-encoded ASCII string of 40 characters, which is 1788 truncated as necessary. 1789 1790 <p>Note that the keys used by the <code>ntpq</code> and <code>ntpdc</code> programs are 1791 checked against passwords requested by the programs and entered by hand, 1792 so it 1793 is generally appropriate to specify these keys in human readable ASCII 1794 format. 1795 1796 <p>The <code>ntp-keygen</code> program generates a MD5 symmetric keys file 1797 <code>ntpkey_MD5key_hostname.filestamp</code>. 1798 Since the file contains private 1799 shared keys, it should be visible only to root and distributed by 1800 secure means to other subnet hosts. 1801 The NTP daemon loads the file <code>ntp.keys</code>, so <code>ntp-keygen</code> 1802 installs a soft link from this name to the generated file. 1803 Subsequently, similar soft links must be installed by 1804 manual or automated means on the other subnet hosts. 1805 While this file is 1806 not used with the Autokey Version 2 protocol, it is needed to 1807 authenticate some remote configuration commands used by the <code>ntpq</code> and 1808 <code>ntpdc</code> utilities. 1809 1810 </body></html> 1811 1812
Indexes created Wed Aug 26 00:26:28 UTC 2026