ca.pod revision 238405
1 2=pod 3 4=head1 NAME 5 6ca - sample minimal CA application 7 8=head1 SYNOPSIS 9 10B<openssl> B<ca> 11[B<-verbose>] 12[B<-config filename>] 13[B<-name section>] 14[B<-gencrl>] 15[B<-revoke file>] 16[B<-crl_reason reason>] 17[B<-crl_hold instruction>] 18[B<-crl_compromise time>] 19[B<-crl_CA_compromise time>] 20[B<-crldays days>] 21[B<-crlhours hours>] 22[B<-crlexts section>] 23[B<-startdate date>] 24[B<-enddate date>] 25[B<-days arg>] 26[B<-md arg>] 27[B<-policy arg>] 28[B<-keyfile arg>] 29[B<-key arg>] 30[B<-passin arg>] 31[B<-cert file>] 32[B<-selfsign>] 33[B<-in file>] 34[B<-out file>] 35[B<-notext>] 36[B<-outdir dir>] 37[B<-infiles>] 38[B<-spkac file>] 39[B<-ss_cert file>] 40[B<-preserveDN>] 41[B<-noemailDN>] 42[B<-batch>] 43[B<-msie_hack>] 44[B<-extensions section>] 45[B<-extfile section>] 46[B<-engine id>] 47[B<-subj arg>] 48[B<-utf8>] 49[B<-multivalue-rdn>] 50 51=head1 DESCRIPTION 52 53The B<ca> command is a minimal CA application. It can be used 54to sign certificate requests in a variety of forms and generate 55CRLs it also maintains a text database of issued certificates 56and their status. 57 58The options descriptions will be divided into each purpose. 59 60=head1 CA OPTIONS 61 62=over 4 63 64=item B<-config filename> 65 66specifies the configuration file to use. 67 68=item B<-name section> 69 70specifies the configuration file section to use (overrides 71B<default_ca> in the B<ca> section). 72 73=item B<-in filename> 74 75an input filename containing a single certificate request to be 76signed by the CA. 77 78=item B<-ss_cert filename> 79 80a single self signed certificate to be signed by the CA. 81 82=item B<-spkac filename> 83 84a file containing a single Netscape signed public key and challenge 85and additional field values to be signed by the CA. See the B<SPKAC FORMAT> 86section for information on the required format. 87 88=item B<-infiles> 89 90if present this should be the last option, all subsequent arguments 91are assumed to be the names of files containing certificate requests. 92 93=item B<-out filename> 94 95the output file to output certificates to. The default is standard 96output. The certificate details will also be printed out to this 97file. 98 99=item B<-outdir directory> 100 101the directory to output certificates to. The certificate will be 102written to a filename consisting of the serial number in hex with 103".pem" appended. 104 105=item B<-cert> 106 107the CA certificate file. 108 109=item B<-keyfile filename> 110 111the private key to sign requests with. 112 113=item B<-key password> 114 115the password used to encrypt the private key. Since on some 116systems the command line arguments are visible (e.g. Unix with 117the 'ps' utility) this option should be used with caution. 118 119=item B<-selfsign> 120 121indicates the issued certificates are to be signed with the key 122the certificate requests were signed with (given with B<-keyfile>). 123Cerificate requests signed with a different key are ignored. If 124B<-spkac>, B<-ss_cert> or B<-gencrl> are given, B<-selfsign> is 125ignored. 126 127A consequence of using B<-selfsign> is that the self-signed 128certificate appears among the entries in the certificate database 129(see the configuration option B<database>), and uses the same 130serial number counter as all other certificates sign with the 131self-signed certificate. 132 133=item B<-passin arg> 134 135the key password source. For more information about the format of B<arg> 136see the B<PASS PHRASE ARGUMENTS> section in L<openssl(1)|openssl(1)>. 137 138=item B<-verbose> 139 140this prints extra details about the operations being performed. 141 142=item B<-notext> 143 144don't output the text form of a certificate to the output file. 145 146=item B<-startdate date> 147 148this allows the start date to be explicitly set. The format of the 149date is YYMMDDHHMMSSZ (the same as an ASN1 UTCTime structure). 150 151=item B<-enddate date> 152 153this allows the expiry date to be explicitly set. The format of the 154date is YYMMDDHHMMSSZ (the same as an ASN1 UTCTime structure). 155 156=item B<-days arg> 157 158the number of days to certify the certificate for. 159 160=item B<-md alg> 161 162the message digest to use. Possible values include md5, sha1 and mdc2. 163This option also applies to CRLs. 164 165=item B<-policy arg> 166 167this option defines the CA "policy" to use. This is a section in 168the configuration file which decides which fields should be mandatory 169or match the CA certificate. Check out the B<POLICY FORMAT> section 170for more information. 171 172=item B<-msie_hack> 173 174this is a legacy option to make B<ca> work with very old versions of 175the IE certificate enrollment control "certenr3". It used UniversalStrings 176for almost everything. Since the old control has various security bugs 177its use is strongly discouraged. The newer control "Xenroll" does not 178need this option. 179 180=item B<-preserveDN> 181 182Normally the DN order of a certificate is the same as the order of the 183fields in the relevant policy section. When this option is set the order 184is the same as the request. This is largely for compatibility with the 185older IE enrollment control which would only accept certificates if their 186DNs match the order of the request. This is not needed for Xenroll. 187 188=item B<-noemailDN> 189 190The DN of a certificate can contain the EMAIL field if present in the 191request DN, however it is good policy just having the e-mail set into 192the altName extension of the certificate. When this option is set the 193EMAIL field is removed from the certificate' subject and set only in 194the, eventually present, extensions. The B<email_in_dn> keyword can be 195used in the configuration file to enable this behaviour. 196 197=item B<-batch> 198 199this sets the batch mode. In this mode no questions will be asked 200and all certificates will be certified automatically. 201 202=item B<-extensions section> 203 204the section of the configuration file containing certificate extensions 205to be added when a certificate is issued (defaults to B<x509_extensions> 206unless the B<-extfile> option is used). If no extension section is 207present then, a V1 certificate is created. If the extension section 208is present (even if it is empty), then a V3 certificate is created. See the:w 209L<x509v3_config(5)|x509v3_config(5)> manual page for details of the 210extension section format. 211 212=item B<-extfile file> 213 214an additional configuration file to read certificate extensions from 215(using the default section unless the B<-extensions> option is also 216used). 217 218=item B<-engine id> 219 220specifying an engine (by its unique B<id> string) will cause B<ca> 221to attempt to obtain a functional reference to the specified engine, 222thus initialising it if needed. The engine will then be set as the default 223for all available algorithms. 224 225=item B<-subj arg> 226 227supersedes subject name given in the request. 228The arg must be formatted as I</type0=value0/type1=value1/type2=...>, 229characters may be escaped by \ (backslash), no spaces are skipped. 230 231=item B<-utf8> 232 233this option causes field values to be interpreted as UTF8 strings, by 234default they are interpreted as ASCII. This means that the field 235values, whether prompted from a terminal or obtained from a 236configuration file, must be valid UTF8 strings. 237 238=item B<-multivalue-rdn> 239 240this option causes the -subj argument to be interpretedt with full 241support for multivalued RDNs. Example: 242 243I</DC=org/DC=OpenSSL/DC=users/UID=123456+CN=John Doe> 244 245If -multi-rdn is not used then the UID value is I<123456+CN=John Doe>. 246 247=back 248 249=head1 CRL OPTIONS 250 251=over 4 252 253=item B<-gencrl> 254 255this option generates a CRL based on information in the index file. 256 257=item B<-crldays num> 258 259the number of days before the next CRL is due. That is the days from 260now to place in the CRL nextUpdate field. 261 262=item B<-crlhours num> 263 264the number of hours before the next CRL is due. 265 266=item B<-revoke filename> 267 268a filename containing a certificate to revoke. 269 270=item B<-crl_reason reason> 271 272revocation reason, where B<reason> is one of: B<unspecified>, B<keyCompromise>, 273B<CACompromise>, B<affiliationChanged>, B<superseded>, B<cessationOfOperation>, 274B<certificateHold> or B<removeFromCRL>. The matching of B<reason> is case 275insensitive. Setting any revocation reason will make the CRL v2. 276 277In practive B<removeFromCRL> is not particularly useful because it is only used 278in delta CRLs which are not currently implemented. 279 280=item B<-crl_hold instruction> 281 282This sets the CRL revocation reason code to B<certificateHold> and the hold 283instruction to B<instruction> which must be an OID. Although any OID can be 284used only B<holdInstructionNone> (the use of which is discouraged by RFC2459) 285B<holdInstructionCallIssuer> or B<holdInstructionReject> will normally be used. 286 287=item B<-crl_compromise time> 288 289This sets the revocation reason to B<keyCompromise> and the compromise time to 290B<time>. B<time> should be in GeneralizedTime format that is B<YYYYMMDDHHMMSSZ>. 291 292=item B<-crl_CA_compromise time> 293 294This is the same as B<crl_compromise> except the revocation reason is set to 295B<CACompromise>. 296 297=item B<-crlexts section> 298 299the section of the configuration file containing CRL extensions to 300include. If no CRL extension section is present then a V1 CRL is 301created, if the CRL extension section is present (even if it is 302empty) then a V2 CRL is created. The CRL extensions specified are 303CRL extensions and B<not> CRL entry extensions. It should be noted 304that some software (for example Netscape) can't handle V2 CRLs. See 305L<x509v3_config(5)|x509v3_config(5)> manual page for details of the 306extension section format. 307 308=back 309 310=head1 CONFIGURATION FILE OPTIONS 311 312The section of the configuration file containing options for B<ca> 313is found as follows: If the B<-name> command line option is used, 314then it names the section to be used. Otherwise the section to 315be used must be named in the B<default_ca> option of the B<ca> section 316of the configuration file (or in the default section of the 317configuration file). Besides B<default_ca>, the following options are 318read directly from the B<ca> section: 319 RANDFILE 320 preserve 321 msie_hack 322With the exception of B<RANDFILE>, this is probably a bug and may 323change in future releases. 324 325Many of the configuration file options are identical to command line 326options. Where the option is present in the configuration file 327and the command line the command line value is used. Where an 328option is described as mandatory then it must be present in 329the configuration file or the command line equivalent (if 330any) used. 331 332=over 4 333 334=item B<oid_file> 335 336This specifies a file containing additional B<OBJECT IDENTIFIERS>. 337Each line of the file should consist of the numerical form of the 338object identifier followed by white space then the short name followed 339by white space and finally the long name. 340 341=item B<oid_section> 342 343This specifies a section in the configuration file containing extra 344object identifiers. Each line should consist of the short name of the 345object identifier followed by B<=> and the numerical form. The short 346and long names are the same when this option is used. 347 348=item B<new_certs_dir> 349 350the same as the B<-outdir> command line option. It specifies 351the directory where new certificates will be placed. Mandatory. 352 353=item B<certificate> 354 355the same as B<-cert>. It gives the file containing the CA 356certificate. Mandatory. 357 358=item B<private_key> 359 360same as the B<-keyfile> option. The file containing the 361CA private key. Mandatory. 362 363=item B<RANDFILE> 364 365a file used to read and write random number seed information, or 366an EGD socket (see L<RAND_egd(3)|RAND_egd(3)>). 367 368=item B<default_days> 369 370the same as the B<-days> option. The number of days to certify 371a certificate for. 372 373=item B<default_startdate> 374 375the same as the B<-startdate> option. The start date to certify 376a certificate for. If not set the current time is used. 377 378=item B<default_enddate> 379 380the same as the B<-enddate> option. Either this option or 381B<default_days> (or the command line equivalents) must be 382present. 383 384=item B<default_crl_hours default_crl_days> 385 386the same as the B<-crlhours> and the B<-crldays> options. These 387will only be used if neither command line option is present. At 388least one of these must be present to generate a CRL. 389 390=item B<default_md> 391 392the same as the B<-md> option. The message digest to use. Mandatory. 393 394=item B<database> 395 396the text database file to use. Mandatory. This file must be present 397though initially it will be empty. 398 399=item B<unique_subject> 400 401if the value B<yes> is given, the valid certificate entries in the 402database must have unique subjects. if the value B<no> is given, 403several valid certificate entries may have the exact same subject. 404The default value is B<yes>, to be compatible with older (pre 0.9.8) 405versions of OpenSSL. However, to make CA certificate roll-over easier, 406it's recommended to use the value B<no>, especially if combined with 407the B<-selfsign> command line option. 408 409=item B<serial> 410 411a text file containing the next serial number to use in hex. Mandatory. 412This file must be present and contain a valid serial number. 413 414=item B<crlnumber> 415 416a text file containing the next CRL number to use in hex. The crl number 417will be inserted in the CRLs only if this file exists. If this file is 418present, it must contain a valid CRL number. 419 420=item B<x509_extensions> 421 422the same as B<-extensions>. 423 424=item B<crl_extensions> 425 426the same as B<-crlexts>. 427 428=item B<preserve> 429 430the same as B<-preserveDN> 431 432=item B<email_in_dn> 433 434the same as B<-noemailDN>. If you want the EMAIL field to be removed 435from the DN of the certificate simply set this to 'no'. If not present 436the default is to allow for the EMAIL filed in the certificate's DN. 437 438=item B<msie_hack> 439 440the same as B<-msie_hack> 441 442=item B<policy> 443 444the same as B<-policy>. Mandatory. See the B<POLICY FORMAT> section 445for more information. 446 447=item B<name_opt>, B<cert_opt> 448 449these options allow the format used to display the certificate details 450when asking the user to confirm signing. All the options supported by 451the B<x509> utilities B<-nameopt> and B<-certopt> switches can be used 452here, except the B<no_signame> and B<no_sigdump> are permanently set 453and cannot be disabled (this is because the certificate signature cannot 454be displayed because the certificate has not been signed at this point). 455 456For convenience the values B<ca_default> are accepted by both to produce 457a reasonable output. 458 459If neither option is present the format used in earlier versions of 460OpenSSL is used. Use of the old format is B<strongly> discouraged because 461it only displays fields mentioned in the B<policy> section, mishandles 462multicharacter string types and does not display extensions. 463 464=item B<copy_extensions> 465 466determines how extensions in certificate requests should be handled. 467If set to B<none> or this option is not present then extensions are 468ignored and not copied to the certificate. If set to B<copy> then any 469extensions present in the request that are not already present are copied 470to the certificate. If set to B<copyall> then all extensions in the 471request are copied to the certificate: if the extension is already present 472in the certificate it is deleted first. See the B<WARNINGS> section before 473using this option. 474 475The main use of this option is to allow a certificate request to supply 476values for certain extensions such as subjectAltName. 477 478=back 479 480=head1 POLICY FORMAT 481 482The policy section consists of a set of variables corresponding to 483certificate DN fields. If the value is "match" then the field value 484must match the same field in the CA certificate. If the value is 485"supplied" then it must be present. If the value is "optional" then 486it may be present. Any fields not mentioned in the policy section 487are silently deleted, unless the B<-preserveDN> option is set but 488this can be regarded more of a quirk than intended behaviour. 489 490=head1 SPKAC FORMAT 491 492The input to the B<-spkac> command line option is a Netscape 493signed public key and challenge. This will usually come from 494the B<KEYGEN> tag in an HTML form to create a new private key. 495It is however possible to create SPKACs using the B<spkac> utility. 496 497The file should contain the variable SPKAC set to the value of 498the SPKAC and also the required DN components as name value pairs. 499If you need to include the same component twice then it can be 500preceded by a number and a '.'. 501 502=head1 EXAMPLES 503 504Note: these examples assume that the B<ca> directory structure is 505already set up and the relevant files already exist. This usually 506involves creating a CA certificate and private key with B<req>, a 507serial number file and an empty index file and placing them in 508the relevant directories. 509 510To use the sample configuration file below the directories demoCA, 511demoCA/private and demoCA/newcerts would be created. The CA 512certificate would be copied to demoCA/cacert.pem and its private 513key to demoCA/private/cakey.pem. A file demoCA/serial would be 514created containing for example "01" and the empty index file 515demoCA/index.txt. 516 517 518Sign a certificate request: 519 520 openssl ca -in req.pem -out newcert.pem 521 522Sign a certificate request, using CA extensions: 523 524 openssl ca -in req.pem -extensions v3_ca -out newcert.pem 525 526Generate a CRL 527 528 openssl ca -gencrl -out crl.pem 529 530Sign several requests: 531 532 openssl ca -infiles req1.pem req2.pem req3.pem 533 534Certify a Netscape SPKAC: 535 536 openssl ca -spkac spkac.txt 537 538A sample SPKAC file (the SPKAC line has been truncated for clarity): 539 540 SPKAC=MIG0MGAwXDANBgkqhkiG9w0BAQEFAANLADBIAkEAn7PDhCeV/xIxUg8V70YRxK2A5 541 CN=Steve Test 542 emailAddress=steve@openssl.org 543 0.OU=OpenSSL Group 544 1.OU=Another Group 545 546A sample configuration file with the relevant sections for B<ca>: 547 548 [ ca ] 549 default_ca = CA_default # The default ca section 550 551 [ CA_default ] 552 553 dir = ./demoCA # top dir 554 database = $dir/index.txt # index file. 555 new_certs_dir = $dir/newcerts # new certs dir 556 557 certificate = $dir/cacert.pem # The CA cert 558 serial = $dir/serial # serial no file 559 private_key = $dir/private/cakey.pem# CA private key 560 RANDFILE = $dir/private/.rand # random number file 561 562 default_days = 365 # how long to certify for 563 default_crl_days= 30 # how long before next CRL 564 default_md = md5 # md to use 565 566 policy = policy_any # default policy 567 email_in_dn = no # Don't add the email into cert DN 568 569 name_opt = ca_default # Subject name display option 570 cert_opt = ca_default # Certificate display option 571 copy_extensions = none # Don't copy extensions from request 572 573 [ policy_any ] 574 countryName = supplied 575 stateOrProvinceName = optional 576 organizationName = optional 577 organizationalUnitName = optional 578 commonName = supplied 579 emailAddress = optional 580 581=head1 FILES 582 583Note: the location of all files can change either by compile time options, 584configuration file entries, environment variables or command line options. 585The values below reflect the default values. 586 587 /usr/local/ssl/lib/openssl.cnf - master configuration file 588 ./demoCA - main CA directory 589 ./demoCA/cacert.pem - CA certificate 590 ./demoCA/private/cakey.pem - CA private key 591 ./demoCA/serial - CA serial number file 592 ./demoCA/serial.old - CA serial number backup file 593 ./demoCA/index.txt - CA text database file 594 ./demoCA/index.txt.old - CA text database backup file 595 ./demoCA/certs - certificate output file 596 ./demoCA/.rnd - CA random seed information 597 598=head1 ENVIRONMENT VARIABLES 599 600B<OPENSSL_CONF> reflects the location of master configuration file it can 601be overridden by the B<-config> command line option. 602 603=head1 RESTRICTIONS 604 605The text database index file is a critical part of the process and 606if corrupted it can be difficult to fix. It is theoretically possible 607to rebuild the index file from all the issued certificates and a current 608CRL: however there is no option to do this. 609 610V2 CRL features like delta CRLs are not currently supported. 611 612Although several requests can be input and handled at once it is only 613possible to include one SPKAC or self signed certificate. 614 615=head1 BUGS 616 617The use of an in memory text database can cause problems when large 618numbers of certificates are present because, as the name implies 619the database has to be kept in memory. 620 621The B<ca> command really needs rewriting or the required functionality 622exposed at either a command or interface level so a more friendly utility 623(perl script or GUI) can handle things properly. The scripts B<CA.sh> and 624B<CA.pl> help a little but not very much. 625 626Any fields in a request that are not present in a policy are silently 627deleted. This does not happen if the B<-preserveDN> option is used. To 628enforce the absence of the EMAIL field within the DN, as suggested by 629RFCs, regardless the contents of the request' subject the B<-noemailDN> 630option can be used. The behaviour should be more friendly and 631configurable. 632 633Cancelling some commands by refusing to certify a certificate can 634create an empty file. 635 636=head1 WARNINGS 637 638The B<ca> command is quirky and at times downright unfriendly. 639 640The B<ca> utility was originally meant as an example of how to do things 641in a CA. It was not supposed to be used as a full blown CA itself: 642nevertheless some people are using it for this purpose. 643 644The B<ca> command is effectively a single user command: no locking is 645done on the various files and attempts to run more than one B<ca> command 646on the same database can have unpredictable results. 647 648The B<copy_extensions> option should be used with caution. If care is 649not taken then it can be a security risk. For example if a certificate 650request contains a basicConstraints extension with CA:TRUE and the 651B<copy_extensions> value is set to B<copyall> and the user does not spot 652this when the certificate is displayed then this will hand the requestor 653a valid CA certificate. 654 655This situation can be avoided by setting B<copy_extensions> to B<copy> 656and including basicConstraints with CA:FALSE in the configuration file. 657Then if the request contains a basicConstraints extension it will be 658ignored. 659 660It is advisable to also include values for other extensions such 661as B<keyUsage> to prevent a request supplying its own values. 662 663Additional restrictions can be placed on the CA certificate itself. 664For example if the CA certificate has: 665 666 basicConstraints = CA:TRUE, pathlen:0 667 668then even if a certificate is issued with CA:TRUE it will not be valid. 669 670=head1 SEE ALSO 671 672L<req(1)|req(1)>, L<spkac(1)|spkac(1)>, L<x509(1)|x509(1)>, L<CA.pl(1)|CA.pl(1)>, 673L<config(5)|config(5)>, L<x509v3_config(5)|x509v3_config(5)> 674 675=cut 676