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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_compromise 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]

       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 format.

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

       -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.

       -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).  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 certificate.

       -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 behaviour.

           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.

       -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 formatted as
           /type_=value_/type1=value1/type2=..., characters may be escaped by \ (backslash), no spaces are

           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.

           /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, 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 YYYYMMDDHHMMSSZ.

       -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

       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 section:
        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. Mandatory.

           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

           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 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
           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 extensions.

           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 '.'.

       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 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/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 configurable.

       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 ignored.

       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), x5_9(1),, config(5)

50                                               2013-03-05                                            CA(1)

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