Fix various doc nits.

[openssl.git] / doc / apps / ca.pod

diff --git a/doc/apps/ca.pod b/doc/apps/ca.pod
index 03209aa6b17a14e892c871efb786ff1771e8a1cd..8dfac0122e787d8dac2a47ae0ccf13fbaecc820a 100644 (file)
--- a/doc/apps/ca.pod
+++ b/doc/apps/ca.pod
@@ -1,4 +1,3 @@
-

 =pod
 
 =head1 NAME
 =pod
 
 =head1 NAME


@@ -8,11 +7,18 @@ ca - sample minimal CA application
 =head1 SYNOPSIS
 
 B<openssl> B<ca>
 =head1 SYNOPSIS
 
 B<openssl> B<ca>

+[B<-help>]

 [B<-verbose>]
 [B<-config filename>]
 [B<-name section>]
 [B<-gencrl>]
 [B<-revoke file>]
 [B<-verbose>]
 [B<-config filename>]
 [B<-name section>]
 [B<-gencrl>]
 [B<-revoke file>]

+[B<-status serial>]
+[B<-updatedb>]
+[B<-crl_reason reason>]
+[B<-crl_hold instruction>]
+[B<-crl_compromise time>]
+[B<-crl_CA_compromise time>]

 [B<-crldays days>]
 [B<-crlhours hours>]
 [B<-crlexts section>]
 [B<-crldays days>]
 [B<-crlhours hours>]
 [B<-crlexts section>]


@@ -22,8 +28,11 @@ B<openssl> B<ca>
 [B<-md arg>]
 [B<-policy arg>]
 [B<-keyfile arg>]
 [B<-md arg>]
 [B<-policy arg>]
 [B<-keyfile arg>]

+[B<-keyform PEM|DER>]

 [B<-key arg>]
 [B<-key arg>]

+[B<-passin arg>]

 [B<-cert file>]
 [B<-cert file>]

+[B<-selfsign>]

 [B<-in file>]
 [B<-out file>]
 [B<-notext>]
 [B<-in file>]
 [B<-out file>]
 [B<-notext>]


@@ -32,9 +41,16 @@ B<openssl> B<ca>
 [B<-spkac file>]
 [B<-ss_cert file>]
 [B<-preserveDN>]
 [B<-spkac file>]
 [B<-ss_cert file>]
 [B<-preserveDN>]

+[B<-noemailDN>]

 [B<-batch>]
 [B<-msie_hack>]
 [B<-extensions section>]
 [B<-batch>]
 [B<-msie_hack>]
 [B<-extensions section>]

+[B<-extfile section>]
+[B<-engine id>]
+[B<-subj arg>]
+[B<-utf8>]
+[B<-create_serial>]
+[B<-multivalue-rdn>]

 
 =head1 DESCRIPTION
 
 
 =head1 DESCRIPTION
 


@@ -45,14 +61,27 @@ and their status.
 
 The options descriptions will be divided into each purpose.
 
 
 The options descriptions will be divided into each purpose.
 

-=head1 CA OPTIONS
+=head1 COMMAND OPTIONS

 
 =over 4
 
 
 =over 4
 

+=item B<-help>
+
+Print out a usage message.
+
+=item B<-verbose>
+
+this prints extra details about the operations being performed.
+

 =item B<-config filename>
 
 specifies the configuration file to use.
 
 =item B<-config filename>
 
 specifies the configuration file to use.
 

+=item B<-name section>
+
+specifies the configuration file section to use (overrides
+B<default_ca> in the B<ca> section).
+

 =item B<-in filename>
 
 an input filename containing a single certificate request to be
 =item B<-in filename>
 
 an input filename containing a single certificate request to be


@@ -65,19 +94,19 @@ a single self signed certificate to be signed by the CA.
 =item B<-spkac filename>
 
 a file containing a single Netscape signed public key and challenge
 =item B<-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 B<NOTES>
-section for information on the required format.
+and additional field values to be signed by the CA. See the B<SPKAC FORMAT>
+section for information on the required input and output format.

 
 =item B<-infiles>
 
 if present this should be the last option, all subsequent arguments
 
 =item B<-infiles>
 
 if present this should be the last option, all subsequent arguments

-are assumed to the the names of files containing certificate requests. 
+are taken as the names of files containing certificate requests.

 
 =item B<-out filename>
 
 the output file to output certificates to. The default is standard
 output. The certificate details will also be printed out to this
 
 =item B<-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.
+file in PEM format (except that B<-spkac> outputs DER format).

 
 =item B<-outdir directory>
 
 
 =item B<-outdir directory>
 


@@ -93,15 +122,35 @@ the CA certificate file.
 
 the private key to sign requests with.
 
 
 the private key to sign requests with.
 

+=item B<-keyform PEM|DER>
+
+the format of the data in the private key file.
+The default is PEM.
+

 =item B<-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.
 
 =item B<-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.
 

-=item B<-verbose>
+=item B<-selfsign>

 
 

-this prints extra details about the operations being performed.
+indicates the issued certificates are to be signed with the key
+the certificate requests were signed with (given with B<-keyfile>).
+Certificate requests signed with a different key are ignored.  If
+B<-spkac>, B<-ss_cert> or B<-gencrl> are given, B<-selfsign> is
+ignored.
+
+A consequence of using B<-selfsign> is that the self-signed
+certificate appears among the entries in the certificate database
+(see the configuration option B<database>), and uses the same
+serial number counter as all other certificates sign with the
+self-signed certificate.
+
+=item B<-passin arg>
+
+the key password source. For more information about the format of B<arg>
+see the B<PASS PHRASE ARGUMENTS> section in L<openssl(1)>.

 
 =item B<-notext>
 
 
 =item B<-notext>
 


@@ -123,7 +172,8 @@ the number of days to certify the certificate for.
 
 =item B<-md alg>
 
 
 =item B<-md alg>
 

-the message digest to use. Possible values include md5, sha1 and mdc2.
+the message digest to use.
+Any digest supported by the OpenSSL B<dgst> command can be used.

 This option also applies to CRLs.
 
 =item B<-policy arg>
 This option also applies to CRLs.
 
 =item B<-policy arg>


@@ -144,11 +194,20 @@ need this option.
 =item B<-preserveDN>
 
 Normally the DN order of a certificate is the same as the order of the
 =item B<-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 
+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.
 
 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.
 

+=item B<-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 B<email_in_dn> keyword can be
+used in the configuration file to enable this behaviour.
+

 =item B<-batch>
 
 this sets the batch mode. In this mode no questions will be asked
 =item B<-batch>
 
 this sets the batch mode. In this mode no questions will be asked


@@ -157,9 +216,53 @@ and all certificates will be certified automatically.
 =item B<-extensions section>
 
 the section of the configuration file containing certificate extensions
 =item B<-extensions section>
 
 the section of the configuration file containing certificate extensions

-to be added when a certificate is issued. 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.
+to be added when a certificate is issued (defaults to B<x509_extensions>
+unless the B<-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
+L<x509v3_config(5)> manual page for details of the
+extension section format.
+
+=item B<-extfile file>
+
+an additional configuration file to read certificate extensions from
+(using the default section unless the B<-extensions> option is also
+used).
+
+=item B<-engine id>
+
+specifying an engine (by its unique B<id> string) will cause B<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.
+
+=item B<-subj arg>
+
+supersedes subject name given in the request.
+The arg must be formatted as I</type0=value0/type1=value1/type2=...>,
+characters may be escaped by \ (backslash), no spaces are skipped.
+
+=item B<-utf8>
+
+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.
+
+=item B<-create_serial>
+
+if reading serial from the text file as specified in the configuration
+fails, specifying this option creates a new random serial to be used as next
+serial number.
+
+=item B<-multivalue-rdn>
+
+This option causes the -subj argument to be interpreted with full
+support for multivalued RDNs. Example:
+
+I</DC=org/DC=OpenSSL/DC=users/UID=123456+CN=John Doe>
+
+If -multi-rdn is not used then the UID value is I<123456+CN=John Doe>.

 
 =back
 
 
 =back
 


@@ -184,6 +287,42 @@ the number of hours before the next CRL is due.
 
 a filename containing a certificate to revoke.
 
 
 a filename containing a certificate to revoke.
 

+=item B<-status serial>
+
+displays the revocation status of the certificate with the specified
+serial number and exits.
+
+=item B<-updatedb>
+
+Updates the database index to purge expired certificates.
+
+=item B<-crl_reason reason>
+
+revocation reason, where B<reason> is one of: B<unspecified>, B<keyCompromise>,
+B<CACompromise>, B<affiliationChanged>, B<superseded>, B<cessationOfOperation>,
+B<certificateHold> or B<removeFromCRL>. The matching of B<reason> is case
+insensitive. Setting any revocation reason will make the CRL v2.
+
+In practice B<removeFromCRL> is not particularly useful because it is only used
+in delta CRLs which are not currently implemented.
+
+=item B<-crl_hold instruction>
+
+This sets the CRL revocation reason code to B<certificateHold> and the hold
+instruction to B<instruction> which must be an OID. Although any OID can be
+used only B<holdInstructionNone> (the use of which is discouraged by RFC2459)
+B<holdInstructionCallIssuer> or B<holdInstructionReject> will normally be used.
+
+=item B<-crl_compromise time>
+
+This sets the revocation reason to B<keyCompromise> and the compromise time to
+B<time>. B<time> should be in GeneralizedTime format that is B<YYYYMMDDHHMMSSZ>.
+
+=item B<-crl_CA_compromise time>
+
+This is the same as B<crl_compromise> except the revocation reason is set to
+B<CACompromise>.
+

 =item B<-crlexts section>
 
 the section of the configuration file containing CRL extensions to
 =item B<-crlexts section>
 
 the section of the configuration file containing CRL extensions to


@@ -191,14 +330,28 @@ 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 B<not> CRL entry extensions.  It should be noted
 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 B<not> CRL entry extensions.  It should be noted

-that some software (for example Netscape) can't handle V2 CRLs. 
+that some software (for example Netscape) can't handle V2 CRLs. See
+L<x509v3_config(5)> manual page for details of the
+extension section format.

 
 =back
 
 =head1 CONFIGURATION FILE OPTIONS
 
 
 =back
 
 =head1 CONFIGURATION FILE OPTIONS
 

-The options for B<ca> are contained in the B<ca> section of the
-configuration file. Many of these are identical to command line
+The section of the configuration file containing options for B<ca>
+is found as follows: If the B<-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 B<default_ca> option of the B<ca> section
+of the configuration file (or in the default section of the
+configuration file). Besides B<default_ca>, the following options are
+read directly from the B<ca> section:
+ RANDFILE
+ preserve
+ msie_hack
+With the exception of B<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
 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


@@ -212,7 +365,7 @@ any) used.
 This specifies a file containing additional B<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
 This specifies a file containing additional B<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. 
+by white space and finally the long name.

 
 =item B<oid_section>
 
 
 =item B<oid_section>
 


@@ -239,12 +392,12 @@ CA private key. Mandatory.
 =item B<RANDFILE>
 
 a file used to read and write random number seed information, or
 =item B<RANDFILE>
 
 a file used to read and write random number seed information, or

-an EGD socket (see L<RAND_egd(3)|RAND_egd(3)>).
+an EGD socket (see L<RAND_egd(3)>).

 
 =item B<default_days>
 
 the same as the B<-days> option. The number of days to certify
 
 =item B<default_days>
 
 the same as the B<-days> option. The number of days to certify

-a certificate for. 
+a certificate for.

 
 =item B<default_startdate>
 
 
 =item B<default_startdate>
 


@@ -265,18 +418,34 @@ least one of these must be present to generate a CRL.
 
 =item B<default_md>
 
 
 =item B<default_md>
 

-the same as the B<-md> option. The message digest to use. Mandatory.
+the same as the B<-md> option. Mandatory.

 
 =item B<database>
 
 the text database file to use. Mandatory. This file must be present
 though initially it will be empty.
 
 
 =item B<database>
 
 the text database file to use. Mandatory. This file must be present
 though initially it will be empty.
 

-=item B<serialfile>
+=item B<unique_subject>
+
+if the value B<yes> is given, the valid certificate entries in the
+database must have unique subjects.  if the value B<no> is given,
+several valid certificate entries may have the exact same subject.
+The default value is B<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 B<no>, especially if combined with
+the B<-selfsign> command line option.
+
+=item B<serial>

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

+=item B<crlnumber>
+
+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.
+

 =item B<x509_extensions>
 
 the same as B<-extensions>.
 =item B<x509_extensions>
 
 the same as B<-extensions>.


@@ -289,6 +458,12 @@ the same as B<-crlexts>.
 
 the same as B<-preserveDN>
 
 
 the same as B<-preserveDN>
 

+=item B<email_in_dn>
+
+the same as B<-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.
+

 =item B<msie_hack>
 
 the same as B<-msie_hack>
 =item B<msie_hack>
 
 the same as B<-msie_hack>


@@ -298,6 +473,37 @@ the same as B<-msie_hack>
 the same as B<-policy>. Mandatory. See the B<POLICY FORMAT> section
 for more information.
 
 the same as B<-policy>. Mandatory. See the B<POLICY FORMAT> section
 for more information.
 

+=item B<name_opt>, B<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 B<x509> utilities B<-nameopt> and B<-certopt> switches can be used
+here, except the B<no_signame> and B<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 B<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 B<strongly> discouraged because
+it only displays fields mentioned in the B<policy> section, mishandles
+multicharacter string types and does not display extensions.
+
+=item B<copy_extensions>
+
+determines how extensions in certificate requests should be handled.
+If set to B<none> or this option is not present then extensions are
+ignored and not copied to the certificate. If set to B<copy> then any
+extensions present in the request that are not already present are copied
+to the certificate. If set to B<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 B<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.
+

 =back
 
 =head1 POLICY FORMAT
 =back
 
 =head1 POLICY FORMAT


@@ -314,7 +520,7 @@ this can be regarded more of a quirk than intended behaviour.
 
 The input to the B<-spkac> command line option is a Netscape
 signed public key and challenge. This will usually come from
 
 The input to the B<-spkac> command line option is a Netscape
 signed public key and challenge. This will usually come from

-the B<KEYGEN> tag in an HTML form to create a new private key. 
+the B<KEYGEN> tag in an HTML form to create a new private key.

 It is however possible to create SPKACs using the B<spkac> utility.
 
 The file should contain the variable SPKAC set to the value of
 It is however possible to create SPKACs using the B<spkac> utility.
 
 The file should contain the variable SPKAC set to the value of


@@ -322,6 +528,10 @@ 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 '.'.
 
 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 B<-out>
+flag is used, but PEM format if sending to stdout or the B<-outdir>
+flag is used.
+

 =head1 EXAMPLES
 
 Note: these examples assume that the B<ca> directory structure is
 =head1 EXAMPLES
 
 Note: these examples assume that the B<ca> directory structure is


@@ -342,6 +552,10 @@ Sign a certificate request:
 
  openssl ca -in req.pem -out newcert.pem
 
 
  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
 Generate a CRL
 
  openssl ca -gencrl -out crl.pem


@@ -366,23 +580,28 @@ A sample configuration file with the relevant sections for B<ca>:
 
  [ ca ]
  default_ca      = CA_default            # The default ca section
 
  [ ca ]
  default_ca      = CA_default            # The default ca section

- 
+

  [ CA_default ]
 
  dir            = ./demoCA              # top dir
  database       = $dir/index.txt        # index file.
  [ CA_default ]
 
  dir            = ./demoCA              # top dir
  database       = $dir/index.txt        # index file.

- new_certs_dir = $dir/newcerts         # new certs dir
- 
+ 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
  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
  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
 
  [ policy_any ]
  countryName            = supplied


@@ -392,18 +611,6 @@ A sample configuration file with the relevant sections for B<ca>:
  commonName             = supplied
  emailAddress           = optional
 
  commonName             = supplied
  emailAddress           = optional
 

-=head1 WARNINGS
-
-The B<ca> command is quirky and at times downright unfriendly.
-
-The B<ca> utility was originally meant as an example of how to do things
-in a CA. It was not supposed be be used as a full blown CA itself:
-nevertheless some people are using it for this purpose.
-
-The B<ca> command is effectively a single user command: no locking is
-done on the various files and attempts to run more than one B<ca> command
-on the same database can have unpredictable results.
-

 =head1 FILES
 
 Note: the location of all files can change either by compile time options,
 =head1 FILES
 
 Note: the location of all files can change either by compile time options,


@@ -428,16 +635,12 @@ be overridden by the B<-config> command line option.
 
 =head1 RESTRICTIONS
 
 
 =head1 RESTRICTIONS
 

-The text database index file is a critical part of the process and 
+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.
 
 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.
 

-CRL entry extensions cannot currently be created: only CRL extensions
-can be added.
-
-V2 CRL features like delta CRL support and CRL numbers are not currently
-supported.
+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.
 
 Although several requests can be input and handled at once it is only
 possible to include one SPKAC or self signed certificate.


@@ -448,32 +651,67 @@ 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.
 
 numbers of certificates are present because, as the name implies
 the database has to be kept in memory.
 

-Certificate request extensions are ignored: some kind of "policy" should
-be included to use certain static extensions and certain extensions
-from the request.
-
-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 easily
-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 B<ca> command really needs rewriting or the required functionality
 exposed at either a command or interface level so a more friendly utility
 The B<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 B<CA.sh> and
-B<CA.pl> help a little but not very much.
+(perl script or GUI) can handle things properly. The script
+B<CA.pl> helps a little but not very much.

 
 Any fields in a request that are not present in a policy are silently
 
 Any fields in a request that are not present in a policy are silently

-deleted. This does not happen if the B<-preserveDN> option is used but
-the extra fields are not displayed when the user is asked to certify
-a request. The behaviour should be more friendly and configurable.
+deleted. This does not happen if the B<-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 B<-noemailDN>
+option can be used. The behaviour should be more friendly and
+configurable.

 
 

-Cancelling some commands by refusing to certify a certificate can
+Canceling some commands by refusing to certify a certificate can

 create an empty file.
 
 create an empty file.
 

+=head1 WARNINGS
+
+The B<ca> command is quirky and at times downright unfriendly.
+
+The B<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 B<ca> command is effectively a single user command: no locking is
+done on the various files and attempts to run more than one B<ca> command
+on the same database can have unpredictable results.
+
+The B<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
+B<copy_extensions> value is set to B<copyall> and the user does not spot
+this when the certificate is displayed then this will hand the requester
+a valid CA certificate.
+
+This situation can be avoided by setting B<copy_extensions> to B<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 B<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.
+

 =head1 SEE ALSO
 
 =head1 SEE ALSO
 

-L<req(1)|req(1)>, L<spkac(1)|spkac(1)>, L<x509(1)|x509(1)>, L<CA.pl(1)|CA.pl(1)>,
-L<config(5)|config(5)>
+L<req(1)>, L<spkac(1)>, L<x509(1)>, L<CA.pl(1)>,
+L<config(5)>, L<x509v3_config(5)>
+
+=head1 COPYRIGHT
+
+Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved.
+
+Licensed under the OpenSSL license (the "License").  You may not use
+this file except in compliance with the License.  You can obtain a copy
+in the file LICENSE in the source distribution or at
+L<https://www.openssl.org/source/license.html>.

 
 =cut
 
 =cut