ca.pod

openssl包含TLS

=item B<certificate>

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

=item B<private_key>

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

=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)>).

=item B<default_days>

the same as the B<-days> option. The number of days to certify
a certificate for. 

=item B<default_startdate>

the same as the B<-startdate> option. The start date to certify
a certificate for. If not set the current time is used.

=item B<default_enddate>

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

=item B<default_crl_hours default_crl_days>

the same as the B<-crlhours> and the B<-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.

=item B<default_md>

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

=item B<database>

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

=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.

=item B<x509_extensions>

the same as B<-extensions>.

=item B<crl_extensions>

the same as B<-crlexts>.

=item B<preserve>

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<policy>

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

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 B<-preserveDN> option is set but
this can be regarded more of a quirk than intended behaviour.

=head1 SPKAC FORMAT

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. 
It is however possible to create SPKACs using the B<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 '.'.

=head1 EXAMPLES

Note: these examples assume that the B<ca> directory structure is
already set up and the relevant files already exist. This usually
involves creating a CA certificate and private key with B<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):

 SPKAC=MIG0MGAwXDANBgkqhkiG9w0BAQEFAANLADBIAkEAn7PDhCeV/xIxUg8V70YRxK2A5
 CN=Steve Test
 emailAddress=[e-mail]
 0.OU=OpenSSL Group
 1.OU=Another Group

A sample configuration file with the relevant sections for B<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

=head1 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

=head1 ENVIRONMENT VARIABLES

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

=head1 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 currently
supported.

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

=head1 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 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
(perl script or GUI) can handle things properly. The scripts B<CA.sh> and
B<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 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
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 requestor
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

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)>

=cut