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CA(1)                               OpenSSL                              CA(1)

       ca - sample minimal CA application

       openssl ca [-verbose] [-config filename] [-name section] [-gencrl]
       [-revoke file] [-crl_reason reason] [-crl_hold instruction] [-crl_com-
       promise time] [-crl_CA_compromise time] [-crldays days] [-crlhours
       hours] [-crlexts section] [-startdate date] [-enddate date] [-days arg]
       [-md arg] [-policy arg] [-keyfile arg] [-key arg] [-passin arg] [-cert
       file] [-selfsign] [-in file] [-out file] [-notext] [-outdir dir]
       [-infiles] [-spkac file] [-ss_cert file] [-preserveDN] [-noemailDN]
       [-batch] [-msie_hack] [-extensions section] [-extfile section] [-engine
       id] [-subj arg] [-utf8] [-multivalue-rdn]

       The ca command is a minimal CA application. It can be used to sign cer-
       tificate requests in a variety of forms and generate CRLs it also main-
       tains a text database of issued certificates and their status.

       The options descriptions will be divided into each purpose.

       -config filename
           specifies the configuration file to use.

       -name section
           specifies the configuration file section to use (overrides
           default_ca in the ca section).

       -in filename
           an input filename containing a single certificate request to be
           signed by the CA.

       -ss_cert filename
           a single self signed certificate to be signed by the CA.

       -spkac filename
           a file containing a single Netscape signed public key and challenge
           and additional field values to be signed by the CA. See the SPKAC
           FORMAT section for information on the required format.

           if present this should be the last option, all subsequent arguments
           are assumed to the the names of files containing certificate

       -out filename
           the output file to output certificates to. The default is standard
           output. The certificate details will also be printed out to this

       -outdir directory
           the directory to output certificates to. The certificate will be
           written to a filename consisting of the serial number in hex with
           ".pem" appended.

           the CA certificate file.

       -keyfile filename
           the private key to sign requests with.

       -key password
           the password used to encrypt the private key. Since on some systems
           the command line arguments are visible (e.g. Unix with the 'ps'
           utility) this option should be used with caution.

           indicates the issued certificates are to be signed with the key the
           certificate requests were signed with (given with -keyfile).  Cer-
           ificate requests signed with a different key are ignored.  If
           -spkac, -ss_cert or -gencrl are given, -selfsign is ignored.

           A consequence of using -selfsign is that the self-signed certifi-
           cate appears among the entries in the certificate database (see the
           configuration option database), and uses the same serial number
           counter as all other certificates sign with the self-signed cer-

       -passin arg
           the key password source. For more information about the format of
           arg see the PASS PHRASE ARGUMENTS section in openssl(1).

           this prints extra details about the operations being performed.

           don't output the text form of a certificate to the output file.

       -startdate date
           this allows the start date to be explicitly set. The format of the
           date is YYMMDDHHMMSSZ (the same as an ASN1 UTCTime structure).

       -enddate date
           this allows the expiry date to be explicitly set. The format of the
           date is YYMMDDHHMMSSZ (the same as an ASN1 UTCTime structure).

       -days arg
           the number of days to certify the certificate for.

       -md alg
           the message digest to use. Possible values include md5, sha1 and
           mdc2.  This option also applies to CRLs.

       -policy arg
           this option defines the CA "policy" to use. This is a section in
           the configuration file which decides which fields should be manda-
           tory or match the CA certificate. Check out the POLICY FORMAT sec-
           tion for more information.

           this is a legacy option to make ca work with very old versions of
           the IE certificate enrollment control "certenr3". It used Univer-
           salStrings for almost everything. Since the old control has various
           security bugs its use is strongly discouraged. The newer control
           "Xenroll" does not need this option.

           Normally the DN order of a certificate is the same as the order of
           the fields in the relevant policy section. When this option is set
           the order is the same as the request. This is largely for compati-
           bility with the older IE enrollment control which would only accept
           certificates if their DNs match the order of the request. This is
           not needed for Xenroll.

           The DN of a certificate can contain the EMAIL field if present in
           the request DN, however it is good policy just having the e-mail
           set into the altName extension of the certificate. When this option
           is set the EMAIL field is removed from the certificate' subject and
           set only in the, eventually present, extensions. The email_in_dn
           keyword can be used in the configuration file to enable this behav-

           this sets the batch mode. In this mode no questions will be asked
           and all certificates will be certified automatically.

       -extensions section
           the section of the configuration file containing certificate exten-
           sions to be added when a certificate is issued (defaults to
           x509_extensions unless the -extfile option is used). If no exten-
           sion section is present then, a V1 certificate is created. If the
           extension section is present (even if it is empty), then a V3 cer-
           tificate is created.

       -extfile file
           an additional configuration file to read certificate extensions
           from (using the default section unless the -extensions option is
           also used).

       -engine id
           specifying an engine (by it's unique id string) will cause req to
           attempt to obtain a functional reference to the specified engine,
           thus initialising it if needed. The engine will then be set as the
           default for all available algorithms.

       -subj arg
           supersedes subject name given in the request.  The arg must be for-
           matted as /type0=value0/type1=value1/type2=..., characters may be
           escaped by \ (backslash), no spaces are skipped.

           this option causes field values to be interpreted as UTF8 strings,
           by default they are interpreted as ASCII. This means that the field
           values, whether prompted from a terminal or obtained from a config-
           uration file, must be valid UTF8 strings.

           this option causes the -subj argument to be interpretedt with full
           support for multivalued RDNs. Example:

           /DC=org/DC=OpenSSL/DC=users/UID=123456+CN=John Doe

           If -multi-rdn is not used then the UID value is 123456+CN=John Doe.

           this option generates a CRL based on information in the index file.

       -crldays num
           the number of days before the next CRL is due. That is the days
           from now to place in the CRL nextUpdate field.

       -crlhours num
           the number of hours before the next CRL is due.

       -revoke filename
           a filename containing a certificate to revoke.

       -crl_reason reason
           revocation reason, where reason is one of: unspecified, keyCompro-
           mise, CACompromise, affiliationChanged, superseded, cessationOfOp-
           eration, certificateHold or removeFromCRL. The matching of reason
           is case insensitive. Setting any revocation reason will make the
           CRL v2.

           In practive removeFromCRL is not particularly useful because it is
           only used in delta CRLs which are not currently implemented.

       -crl_hold instruction
           This sets the CRL revocation reason code to certificateHold and the
           hold instruction to instruction which must be an OID. Although any
           OID can be used only holdInstructionNone (the use of which is dis-
           couraged by RFC2459) holdInstructionCallIssuer or holdInstruction-
           Reject will normally be used.

       -crl_compromise time
           This sets the revocation reason to keyCompromise and the compromise
           time to time. time should be in GeneralizedTime format that is

       -crl_CA_compromise time
           This is the same as crl_compromise except the revocation reason is
           set to CACompromise.

       -crlexts section
           the section of the configuration file containing CRL extensions to
           include. If no CRL extension section is present then a V1 CRL is
           created, if the CRL extension section is present (even if it is
           empty) then a V2 CRL is created. The CRL extensions specified are
           CRL extensions and not CRL entry extensions.  It should be noted
           that some software (for example Netscape) can't handle V2 CRLs.

       The section of the configuration file containing options for ca is
       found as follows: If the -name command line option is used, then it
       names the section to be used. Otherwise the section to be used must be
       named in the default_ca option of the ca section of the configuration
       file (or in the default section of the configuration file). Besides
       default_ca, the following options are read directly from the ca sec-
        msie_hack With the exception of RANDFILE, this is probably a bug and
       may change in future releases.

       Many of the configuration file options are identical to command line
       options. Where the option is present in the configuration file and the
       command line the command line value is used. Where an option is
       described as mandatory then it must be present in the configuration
       file or the command line equivalent (if any) used.

           This specifies a file containing additional OBJECT IDENTIFIERS.
           Each line of the file should consist of the numerical form of the
           object identifier followed by white space then the short name fol-
           lowed by white space and finally the long name.

           This specifies a section in the configuration file containing extra
           object identifiers. Each line should consist of the short name of
           the object identifier followed by = and the numerical form. The
           short and long names are the same when this option is used.

           the same as the -outdir command line option. It specifies the
           directory where new certificates will be placed. Mandatory.

           the same as -cert. It gives the file containing the CA certificate.

           same as the -keyfile option. The file containing the CA private
           key. Mandatory.

           a file used to read and write random number seed information, or an
           EGD socket (see RAND_egd(3)).

           the same as the -days option. The number of days to certify a cer-
           tificate for.

           the same as the -startdate option. The start date to certify a cer-
           tificate for. If not set the current time is used.

           the same as the -enddate option. Either this option or default_days
           (or the command line equivalents) must be present.

       default_crl_hours default_crl_days
           the same as the -crlhours and the -crldays options. These will only
           be used if neither command line option is present. At least one of
           these must be present to generate a CRL.

           the same as the -md option. The message digest to use. Mandatory.

           the text database file to use. Mandatory. This file must be present
           though initially it will be empty.

           if the value yes is given, the valid certificate entries in the
           database must have unique subjects.  if the value no is given, sev-
           eral valid certificate entries may have the exact same subject.
           The default value is yes, to be compatible with older (pre 0.9.8)
           versions of OpenSSL.  However, to make CA certificate roll-over
           easier, it's recommended to use the value no, especially if com-
           bined with the -selfsign command line option.

           a text file containing the next serial number to use in hex. Manda-
           tory.  This file must be present and contain a valid serial number.

           a text file containing the next CRL number to use in hex. The crl
           number will be inserted in the CRLs only if this file exists. If
           this file is present, it must contain a valid CRL number.

           the same as -extensions.

           the same as -crlexts.

           the same as -preserveDN

           the same as -noemailDN. If you want the EMAIL field to be removed
           from the DN of the certificate simply set this to 'no'. If not
           present the default is to allow for the EMAIL filed in the certifi-
           cate's DN.

           the same as -msie_hack

           the same as -policy. Mandatory. See the POLICY FORMAT section for
           more information.

       name_opt, cert_opt
           these options allow the format used to display the certificate
           details when asking the user to confirm signing. All the options
           supported by the x509 utilities -nameopt and -certopt switches can
           be used here, except the no_signame and no_sigdump are permanently
           set and cannot be disabled (this is because the certificate signa-
           ture cannot be displayed because the certificate has not been
           signed at this point).

           For convenience the values ca_default are accepted by both to pro-
           duce a reasonable output.

           If neither option is present the format used in earlier versions of
           OpenSSL is used. Use of the old format is strongly discouraged
           because it only displays fields mentioned in the policy section,
           mishandles multicharacter string types and does not display exten-

           determines how extensions in certificate requests should be han-
           dled.  If set to none or this option is not present then extensions
           are ignored and not copied to the certificate. If set to copy then
           any extensions present in the request that are not already present
           are copied to the certificate. If set to copyall then all exten-
           sions in the request are copied to the certificate: if the exten-
           sion is already present in the certificate it is deleted first. See
           the WARNINGS section before using this option.

           The main use of this option is to allow a certificate request to
           supply values for certain extensions such as subjectAltName.

       The policy section consists of a set of variables corresponding to cer-
       tificate DN fields. If the value is "match" then the field value must
       match the same field in the CA certificate. If the value is "supplied"
       then it must be present. If the value is "optional" then it may be
       present. Any fields not mentioned in the policy section are silently
       deleted, unless the -preserveDN option is set but this can be regarded
       more of a quirk than intended behaviour.

       The input to the -spkac command line option is a Netscape signed public
       key and challenge. This will usually come from the KEYGEN tag in an
       HTML form to create a new private key.  It is however possible to cre-
       ate SPKACs using the spkac utility.

       The file should contain the variable SPKAC set to the value of the
       SPKAC and also the required DN components as name value pairs.  If you
       need to include the same component twice then it can be preceded by a
       number and a '.'.

       Note: these examples assume that the ca directory structure is already
       set up and the relevant files already exist. This usually involves cre-
       ating a CA certificate and private key with req, a serial number file
       and an empty index file and placing them in the relevant directories.

       To use the sample configuration file below the directories demoCA,
       demoCA/private and demoCA/newcerts would be created. The CA certificate
       would be copied to demoCA/cacert.pem and its private key to demoCA/pri-
       vate/cakey.pem. A file demoCA/serial would be created containing for
       example "01" and the empty index file demoCA/index.txt.

       Sign a certificate request:

        openssl ca -in req.pem -out newcert.pem

       Sign a certificate request, using CA extensions:

        openssl ca -in req.pem -extensions v3_ca -out newcert.pem

       Generate a CRL

        openssl ca -gencrl -out crl.pem

       Sign several requests:

        openssl ca -infiles req1.pem req2.pem req3.pem

       Certify a Netscape SPKAC:

        openssl ca -spkac spkac.txt

       A sample SPKAC file (the SPKAC line has been truncated for clarity):

        CN=Steve Test
        0.OU=OpenSSL Group
        1.OU=Another Group

       A sample configuration file with the relevant sections for ca:

        [ ca ]
        default_ca      = CA_default            # The default ca section

        [ CA_default ]

        dir            = ./demoCA              # top dir
        database       = $dir/index.txt        # index file.
        new_certs_dir  = $dir/newcerts         # new certs dir

        certificate    = $dir/cacert.pem       # The CA cert
        serial         = $dir/serial           # serial no file
        private_key    = $dir/private/cakey.pem# CA private key
        RANDFILE       = $dir/private/.rand    # random number file

        default_days   = 365                   # how long to certify for
        default_crl_days= 30                   # how long before next CRL
        default_md     = md5                   # md to use

        policy         = policy_any            # default policy
        email_in_dn    = no                    # Don't add the email into cert DN

        name_opt       = ca_default            # Subject name display option
        cert_opt       = ca_default            # Certificate display option
        copy_extensions = none                 # Don't copy extensions from request

        [ policy_any ]
        countryName            = supplied
        stateOrProvinceName    = optional
        organizationName       = optional
        organizationalUnitName = optional
        commonName             = supplied
        emailAddress           = optional

       Note: the location of all files can change either by compile time
       options, configuration file entries, environment variables or command
       line options.  The values below reflect the default values.

        /usr/local/ssl/lib/openssl.cnf - master configuration file
        ./demoCA                       - main CA directory
        ./demoCA/cacert.pem            - CA certificate
        ./demoCA/private/cakey.pem     - CA private key
        ./demoCA/serial                - CA serial number file
        ./demoCA/serial.old            - CA serial number backup file
        ./demoCA/index.txt             - CA text database file
        ./demoCA/index.txt.old         - CA text database backup file
        ./demoCA/certs                 - certificate output file
        ./demoCA/.rnd                  - CA random seed information

       OPENSSL_CONF reflects the location of master configuration file it can
       be overridden by the -config command line option.

       The text database index file is a critical part of the process and if
       corrupted it can be difficult to fix. It is theoretically possible to
       rebuild the index file from all the issued certificates and a current
       CRL: however there is no option to do this.

       V2 CRL features like delta CRLs are not currently supported.

       Although several requests can be input and handled at once it is only
       possible to include one SPKAC or self signed certificate.

       The use of an in memory text database can cause problems when large
       numbers of certificates are present because, as the name implies the
       database has to be kept in memory.

       The ca command really needs rewriting or the required functionality
       exposed at either a command or interface level so a more friendly util-
       ity (perl script or GUI) can handle things properly. The scripts
       and help a little but not very much.

       Any fields in a request that are not present in a policy are silently
       deleted. This does not happen if the -preserveDN option is used. To
       enforce the absence of the EMAIL field within the DN, as suggested by
       RFCs, regardless the contents of the request' subject the -noemailDN
       option can be used. The behaviour should be more friendly and config-

       Cancelling some commands by refusing to certify a certificate can cre-
       ate an empty file.

       The ca command is quirky and at times downright unfriendly.

       The ca utility was originally meant as an example of how to do things
       in a CA. It was not supposed to be used as a full blown CA itself: nev-
       ertheless some people are using it for this purpose.

       The ca command is effectively a single user command: no locking is done
       on the various files and attempts to run more than one ca command on
       the same database can have unpredictable results.

       The copy_extensions option should be used with caution. If care is not
       taken then it can be a security risk. For example if a certificate
       request contains a basicConstraints extension with CA:TRUE and the
       copy_extensions value is set to copyall and the user does not spot this
       when the certificate is displayed then this will hand the requestor a
       valid CA certificate.

       This situation can be avoided by setting copy_extensions to copy and
       including basicConstraints with CA:FALSE in the configuration file.
       Then if the request contains a basicConstraints extension it will be

       It is advisable to also include values for other extensions such as
       keyUsage to prevent a request supplying its own values.

       Additional restrictions can be placed on the CA certificate itself.
       For example if the CA certificate has:

        basicConstraints = CA:TRUE, pathlen:0

       then even if a certificate is issued with CA:TRUE it will not be valid.

       req(1), spkac(1), x509(1),, config(5)

0.9.8k                            2009-06-14                             CA(1)


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