NAME
    ca - sample minimal CA application

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

DESCRIPTION
    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.

CA OPTIONS
    -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.

    -infiles
   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.

    -cert
   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.

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

    -verbose
   this prints extra details about the operations being performed.

    -notext
   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.

    -msie_hack
   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.

    -preserveDN
   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.

    -noemailDN
   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.

    -batch
   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.

CRL OPTIONS
    -gencrl
   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
   YYYYMMDDHHMMSSZ.

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

    -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.

    -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.

CONFIGURATION FILE OPTIONS
    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-
    tion:
 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.

    oid_file
   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.

    oid_section
   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.

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

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

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

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

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

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

    default_enddate
   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.

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

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

    serialfile
   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.

    x509_extensions
   the same as -extensions.

    crl_extensions
   the same as -crlexts.

    preserve
   the same as -preserveDN

    email_in_dn
   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.

    msie_hack
   the same as -msie_hack

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

    nameopt, certopt
   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 default_ca 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-
   sions.

    copy_extensions
   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.

POLICY FORMAT
    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.

SPKAC FORMAT
    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 '.'.

EXAMPLES
    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):

 SPKAC=MIG0MGAwXDANBgkqhkiG9w0BAQEFAANLADBIAkEAn7PDhCeV/xIxUg8V70YRxK2A5
 CN=Steve Test
 emailAddress=steve@openssl.org
 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

 nameopt     = default_ca     # Subject name display option
 certopt     = default_ca     # 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

FILES
    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

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

RESTRICTIONS
    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 CRL support and CRL numbers are not cur-
    rently supported.

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

BUGS
    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.

    It is not possible to certify two certificates with the same DN: this
    is a side effect of how the text database is indexed and it cannot eas-
    ily be fixed without introducing other problems. Some S/MIME clients
    can use two certificates with the same DN for separate signing and
    encryption keys.

    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 CA.sh
    and CA.pl 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-
    urable.

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

WARNINGS
    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
    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.

SEE ALSO
   req(1),spkac(1),x509(1), CA.pl(1), config(5)