Provided by: gnutls-bin_3.8.1-4ubuntu1.3_amd64 bug

NAME

       ocsptool - GnuTLS OCSP tool

SYNOPSIS

       ocsptool [-flags] [-flag [value]] [--option-name[[=| ]value]]

       All arguments must be options.

DESCRIPTION

       On verification
       Responses   are   typically   signed/issued  by  designated  certificates  or  certificate
       authorities and thus this tool requires on verification the certificate of the  issuer  or
       the  full  certificate  chain in order to determine the appropriate signing authority. The
       specified certificate of the issuer is assumed trusted.

OPTIONS

       -d num, --debug=num
              Enable debugging.  This option takes an integer number as its argument.  The  value
              of num is constrained to being:
                  in the range 0 through 9999

              Specifies the debug level.

       -V, --verbose
              More verbose output.

       --infile=file
              Input file.

       --outfile=str
              Output file.

       --ask=server name|url
              Ask an OCSP/HTTP server on a certificate validity.

              Connects to the specified HTTP OCSP server and queries on the validity of the
              loaded certificate.  Its argument can be a URL or a plain server name. It can be
              combined with --load-chain, where it checks all certificates in the provided chain,
              or with --load-cert and --load-issuer options. The latter checks the provided
              certificate against its specified issuer certificate.

       -e, --verify-response
              Verify response.

              Verifies the provided OCSP response against the system trust anchors (unless
              --load-trust is provided). It requires the --load-signer or --load-chain options to
              obtain the signer of the OCSP response.

       -i, --request-info
              Print information on a OCSP request.

              Display detailed information on the provided OCSP request.

       -j, --response-info
              Print information on a OCSP response.

              Display detailed information on the provided OCSP response.

       -q, --generate-request
              Generates an OCSP request.

       --nonce, --no-nonce
              Use (or not) a nonce to OCSP request.  The no-nonce form will disable the option.

       --load-chain=file
              Reads a set of certificates forming a chain from file.

       --load-issuer=file
              Reads issuer's certificate from file.

       --load-cert=file
              Reads the certificate to check from file.

       --load-trust=file
              Read OCSP trust anchors from file.  This option must not appear in combination with
              any of the following options: load-signer.

              When verifying an OCSP response read the trust anchors from the provided file. When
              this is not provided, the system's trust anchors will be used.

       --load-signer=file
              Reads the OCSP response signer from file.  This option must not appear in
              combination with any of the following options: load-trust.

       --inder, --no-inder
              Use DER format for input certificates and private keys.  The no-inder form will
              disable the option.

       --outder
              Use DER format for output of responses (this is the default).

              The output will be in DER encoded format. Unlike other GnuTLS tools, this is the
              default for this tool

       --outpem
              Use PEM format for output of responses.

              The output will be in PEM format.

       -Q file, --load-request=file
              Reads the DER encoded OCSP request from file.

       -S file, --load-response=file
              Reads the DER encoded OCSP response from file.

       --ignore-errors
              Ignore any verification errors.

       --verify-allow-broken
              Allow broken algorithms, such as MD5 for verification.

              This can be combined with --verify-response.

       --attime=timestamp
              Perform validation at the timestamp instead of the system time.

              timestamp is an instance in time encoded as Unix time or in a human
               readable timestring such as "29 Feb 2004", "2004-02-29".  Full documentation
              available at
              <https://www.gnu.org/software/coreutils/manual/html_node/Date-input-formats.html>
              or locally via info '(coreutils) date invocation'.

       -v arg, --version=arg
              Output version of program and exit.  The default mode is `v', a simple version.
              The `c' mode will print copyright information and `n' will print the full copyright
              notice.

       -h, --help
              Display usage information and exit.

       -!, --more-help
              Pass the extended usage information through a pager.

EXAMPLES

       Print information about an OCSP request

       To parse an OCSP request and print information about the content, the -i or --request-info
       parameter may be used as follows.  The -Q parameter specify the name of the file
       containing the OCSP request, and it should contain the OCSP request in binary DER format.

           $ ocsptool -i -Q ocsp-request.der

       The input file may also be sent to standard input like this:

           $ cat ocsp-request.der | ocsptool --request-info

       Print information about an OCSP response

       Similar to parsing OCSP requests, OCSP responses can be parsed using the -j or
       --response-info as follows.

           $ ocsptool -j -Q ocsp-response.der
           $ cat ocsp-response.der | ocsptool --response-info

       Generate an OCSP request

       The -q or --generate-request parameters are used to generate an OCSP request.  By default
       the OCSP request is written to standard output in binary DER format, but can be stored in
       a file using --outfile.  To generate an OCSP request the issuer of the certificate to
       check needs to be specified with --load-issuer and the certificate to check with
       --load-cert.  By default PEM format is used for these files, although --inder can be used
       to specify that the input files are in DER format.

           $ ocsptool -q --load-issuer issuer.pem --load-cert client.pem            --outfile ocsp-request.der

       When generating OCSP requests, the tool will add an OCSP extension containing a nonce.
       This behaviour can be disabled by specifying --no-nonce.

       Verify signature in OCSP response

       To verify the signature in an OCSP response the -e or --verify-response parameter is used.
       The tool will read an OCSP response in DER format from standard input, or from the file
       specified by --load-response.  The OCSP response is verified against a set of trust
       anchors, which are specified using --load-trust.  The trust anchors are concatenated
       certificates in PEM format.  The certificate that signed the OCSP response needs to be in
       the set of trust anchors, or the issuer of the signer certificate needs to be in the set
       of trust anchors and the OCSP Extended Key Usage bit has to be asserted in the signer
       certificate.

           $ ocsptool -e --load-trust issuer.pem            --load-response ocsp-response.der

       The tool will print status of verification.

       Verify signature in OCSP response against given certificate

       It is possible to override the normal trust logic if you know that a certain certificate
       is supposed to have signed the OCSP response, and you want to use it to check the
       signature.  This is achieved using --load-signer instead of --load-trust.  This will load
       one certificate and it will be used to verify the signature in the OCSP response.  It will
       not check the Extended Key Usage bit.

           $ ocsptool -e --load-signer ocsp-signer.pem            --load-response ocsp-response.der

       This approach is normally only relevant in two situations.  The first is when the OCSP
       response does not contain a copy of the signer certificate, so the --load-trust code would
       fail.  The second is if you want to avoid the indirect mode where the OCSP response signer
       certificate is signed by a trust anchor.

       Real-world example

       Here is an example of how to generate an OCSP request for a certificate and to verify the
       response.  For illustration we'll use the blog.josefsson.org host, which (as of writing)
       uses a certificate from CACert.  First we'll use gnutls-cli to get a copy of the server
       certificate chain.  The server is not required to send this information, but this
       particular one is configured to do so.

           $ echo | gnutls-cli -p 443 blog.josefsson.org --save-cert chain.pem

       The saved certificates normally contain a pointer to where the OCSP responder is located,
       in the Authority Information Access Information extension.  For example, from certtool -i
       < chain.pem there is this information:

                     Authority Information Access Information (not critical):
                          Access Method: 1.3.6.1.5.5.7.48.1 (id-ad-ocsp)
                          Access Location URI: https://ocsp.CAcert.org/

       This means that ocsptool can discover the servers to contact over HTTP.  We can now
       request information on the chain certificates.

           $ ocsptool --ask --load-chain chain.pem

       The request is sent via HTTP to the OCSP server address found in the certificates. It is
       possible to override the address of the OCSP server as well as ask information on a
       particular certificate using --load-cert and --load-issuer.

           $ ocsptool --ask https://ocsp.CAcert.org/ --load-chain chain.pem

EXIT STATUS

       One of the following exit values will be returned:

       0  (EXIT_SUCCESS)
              Successful program execution.

       1  (EXIT_FAILURE)
              The operation failed or the command syntax was not valid.

SEE ALSO

       certtool (1)

AUTHORS

COPYRIGHT

       Copyright (C) 2020-2023 Free Software Foundation, and others all rights reserved.  This
       program is released under the terms of the GNU General Public License, version 3 or later

BUGS

       Please send bug reports to: bugs@gnutls.org