ca - sample minimal CA application


   openssl ca [-verbose] [-config filename] [-name section] [-gencrl]
   [-revoke file] [-status serial] [-updatedb] [-crl_reason reason]
   [-crl_hold instruction] [-crl_compromise time] [-crl_CA_compromise
   time] [-crldays days] [-crlhours hours] [-crlexts section] [-startdate
   date] [-enddate date] [-days arg] [-md arg] [-policy arg] [-keyfile
   arg] [-keyform PEM|DER] [-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
   certificate requests in a variety of forms and generate CRLs it also
   maintains 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 input and output

       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
       file in PEM format (except that -spkac outputs DER format).

   -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.

   -keyform PEM|DER
       the format of the data in the private key file.  The default is

   -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).
       Cerificate 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
       certificate 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

   -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
       mandatory or match the CA certificate. Check out the POLICY FORMAT
       section 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
       UniversalStrings 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
       compatibility 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

       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
       extensions to be added when a certificate is issued (defaults to
       x509_extensions unless the -extfile option is used). If no
       extension section is present then, a V1 certificate is created. If
       the extension section is present (even if it is empty), then a V3
       certificate is created. See the:w x509v3_config(5) manual page for
       details of the extension section format.

   -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 its unique id string) will cause ca 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
       formatted 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
       configuration 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.

   -status serial
       displays the revocation status of the certificate with the
       specified serial number and exits.

       Updates the database index to purge expired certificates.

   -crl_reason reason
       revocation reason, where reason is one of: unspecified,
       keyCompromise, CACompromise, affiliationChanged, superseded,
       cessationOfOperation, 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
       discouraged by RFC2459) holdInstructionCallIssuer or
       holdInstructionReject 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. See
       x509v3_config(5) manual page for details of the extension section


   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
    RANDFILE  preserve
    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
       followed 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
       certificate for.

       the same as the -startdate option. The start date to certify a
       certificate 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,
       several 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
       combined with the -selfsign command line option.

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

       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
       certificate'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
       signature cannot be displayed because the certificate has not been
       signed at this point).

       For convenience the values ca_default are accepted by both to
       produce 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

       determines how extensions in certificate requests should be
       handled.  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 extensions in the request are copied to the certificate:
       if the extension 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
   certificate 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
   create 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 '.'.

   When processing SPKAC format, the output is DER if the -out flag is
   used, but PEM format if sending to stdout or the -outdir flag is used.


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

   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/private/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
   utility (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

   Cancelling some commands by refusing to certify a certificate can
   create 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:
   nevertheless 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), x509v3_config(5)


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