1ocsptool(1)                      User Commands                     ocsptool(1)
2
3
4

NAME

6       ocsptool - GnuTLS OCSP tool
7

SYNOPSIS

9       ocsptool [-flags] [-flag [value]] [--option-name[[=| ]value]]
10
11       All arguments must be options.
12

DESCRIPTION

14       On verification
15       Responses  are  typically  signed/issued  by designated certificates or
16       certificate authorities and thus this tool requires on verification the
17       certificate of the issuer or the full certificate chain in order to de‐
18       termine the appropriate signing authority. The specified certificate of
19       the issuer is assumed trusted.
20
21
22

OPTIONS

24       -d num, --debug=num
25              Enable  debugging.   This  option takes an integer number as its
26              argument.  The value of num is constrained to being:
27                  in the range 0 through 9999
28
29              Specifies the debug level.
30
31       -V, --verbose
32              More verbose output.
33
34
35       --infile=file
36              Input file.
37
38
39       --outfile=str
40              Output file.
41
42
43       --ask=server name|url
44              Ask an OCSP/HTTP server on a certificate validity.
45
46              Connects to the specified HTTP OCSP server and queries on the
47              validity of the loaded certificate.  Its argument can be a URL
48              or a plain server name. It can be combined with --load-chain,
49              where it checks all certificates in the provided chain, or with
50              --load-cert and --load-issuer options. The latter checks the
51              provided certificate against its specified issuer certificate.
52
53       -e, --verify-response
54              Verify response.
55
56              Verifies the provided OCSP response against the system trust an‐
57              chors (unless --load-trust is provided). It requires the
58              --load-signer or --load-chain options to obtain the signer of
59              the OCSP response.
60
61       -i, --request-info
62              Print information on a OCSP request.
63
64              Display detailed information on the provided OCSP request.
65
66       -j, --response-info
67              Print information on a OCSP response.
68
69              Display detailed information on the provided OCSP response.
70
71       -q, --generate-request
72              Generates an OCSP request.
73
74
75       --nonce, --no-nonce
76              Use (or not) a nonce to OCSP request.  The no-nonce form will
77              disable the option.
78
79
80       --load-chain=file
81              Reads a set of certificates forming a chain from file.
82
83
84       --load-issuer=file
85              Reads issuer's certificate from file.
86
87
88       --load-cert=file
89              Reads the certificate to check from file.
90
91
92       --load-trust=file
93              Read OCSP trust anchors from file.  This option must not appear
94              in combination with any of the following options: load-signer.
95
96              When verifying an OCSP response read the trust anchors from the
97              provided file. When this is not provided, the system's trust an‐
98              chors will be used.
99
100       --load-signer=file
101              Reads the OCSP response signer from file.  This option must not
102              appear in combination with any of the following options: load-
103              trust.
104
105
106       --inder, --no-inder
107              Use DER format for input certificates and private keys.  The
108              no-inder form will disable the option.
109
110
111       --outder
112              Use DER format for output of responses (this is the default).
113
114              The output will be in DER encoded format. Unlike other GnuTLS
115              tools, this is the default for this tool
116
117       --outpem
118              Use PEM format for output of responses.
119
120              The output will be in PEM format.
121
122       -Q file, --load-request=file
123              Reads the DER encoded OCSP request from file.
124
125
126       -S file, --load-response=file
127              Reads the DER encoded OCSP response from file.
128
129
130       --ignore-errors
131              Ignore any verification errors.
132
133
134       --verify-allow-broken
135              Allow broken algorithms, such as MD5 for verification.
136
137              This can be combined with --verify-response.
138
139       --attime=timestamp
140              Perform validation at the timestamp instead of the system time.
141
142              timestamp is an instance in time encoded as Unix time or in a
143              human
144               readable timestring such as "29 Feb 2004", "2004-02-29".  Full
145              documentation available at <https://www.gnu.org/software/core
146              utils/manual/html_node/Date-input-formats.html> or locally via
147              info '(coreutils) date invocation'.
148
149       -v arg, --version=arg
150              Output version of program and exit.  The default mode is `v', a
151              simple version.  The `c' mode will print copyright information
152              and `n' will print the full copyright notice.
153
154       -h, --help
155              Display usage information and exit.
156
157       -!, --more-help
158              Pass the extended usage information through a pager.
159
160
161

EXAMPLES

163       Print information about an OCSP request
164
165       To parse an OCSP request and print information about the content, the
166       -i or --request-info parameter may be used as follows.  The -Q parame‐
167       ter specify the name of the file containing the OCSP request, and it
168       should contain the OCSP request in binary DER format.
169
170           $ ocsptool -i -Q ocsp-request.der
171
172       The input file may also be sent to standard input like this:
173
174           $ cat ocsp-request.der | ocsptool --request-info
175
176       Print information about an OCSP response
177
178       Similar to parsing OCSP requests, OCSP responses can be parsed using
179       the -j or --response-info as follows.
180
181           $ ocsptool -j -Q ocsp-response.der
182           $ cat ocsp-response.der | ocsptool --response-info
183
184       Generate an OCSP request
185
186       The -q or --generate-request parameters are used to generate an OCSP
187       request.  By default the OCSP request is written to standard output in
188       binary DER format, but can be stored in a file using --outfile.  To
189       generate an OCSP request the issuer of the certificate to check needs
190       to be specified with --load-issuer and the certificate to check with
191       --load-cert.  By default PEM format is used for these files, although
192       --inder can be used to specify that the input files are in DER format.
193
194           $ ocsptool -q --load-issuer issuer.pem --load-cert client.pem            --outfile ocsp-request.der
195
196       When generating OCSP requests, the tool will add an OCSP extension con‐
197       taining a nonce.  This behaviour can be disabled by specifying
198       --no-nonce.
199
200       Verify signature in OCSP response
201
202       To verify the signature in an OCSP response the -e or --verify-response
203       parameter is used.  The tool will read an OCSP response in DER format
204       from standard input, or from the file specified by --load-response.
205       The OCSP response is verified against a set of trust anchors, which are
206       specified using --load-trust.  The trust anchors are concatenated cer‐
207       tificates in PEM format.  The certificate that signed the OCSP response
208       needs to be in the set of trust anchors, or the issuer of the signer
209       certificate needs to be in the set of trust anchors and the OCSP Ex‐
210       tended Key Usage bit has to be asserted in the signer certificate.
211
212           $ ocsptool -e --load-trust issuer.pem            --load-response ocsp-response.der
213
214       The tool will print status of verification.
215
216       Verify signature in OCSP response against given certificate
217
218       It is possible to override the normal trust logic if you know that a
219       certain certificate is supposed to have signed the OCSP response, and
220       you want to use it to check the signature.  This is achieved using
221       --load-signer instead of --load-trust.  This will load one certificate
222       and it will be used to verify the signature in the OCSP response.  It
223       will not check the Extended Key Usage bit.
224
225           $ ocsptool -e --load-signer ocsp-signer.pem            --load-response ocsp-response.der
226
227       This approach is normally only relevant in two situations.  The first
228       is when the OCSP response does not contain a copy of the signer cer‐
229       tificate, so the --load-trust code would fail.  The second is if you
230       want to avoid the indirect mode where the OCSP response signer certifi‐
231       cate is signed by a trust anchor.
232
233       Real-world example
234
235       Here is an example of how to generate an OCSP request for a certificate
236       and to verify the response.  For illustration we'll use the blog.josef‐
237       sson.org host, which (as of writing) uses a certificate from CACert.
238       First we'll use gnutls-cli to get a copy of the server certificate
239       chain.  The server is not required to send this information, but this
240       particular one is configured to do so.
241
242           $ echo | gnutls-cli -p 443 blog.josefsson.org --save-cert chain.pem
243
244       The saved certificates normally contain a pointer to where the OCSP re‐
245       sponder is located, in the Authority Information Access Information ex‐
246       tension.  For example, from certtool -i < chain.pem there is this in‐
247       formation:
248
249                     Authority Information Access Information (not critical):
250                          Access Method: 1.3.6.1.5.5.7.48.1 (id-ad-ocsp)
251                          Access Location URI: https://ocsp.CAcert.org/
252
253       This means that ocsptool can discover the servers to contact over HTTP.
254       We can now request information on the chain certificates.
255
256           $ ocsptool --ask --load-chain chain.pem
257
258       The request is sent via HTTP to the OCSP server address found in the
259       certificates. It is possible to override the address of the OCSP server
260       as well as ask information on a particular certificate using
261       --load-cert and --load-issuer.
262
263           $ ocsptool --ask https://ocsp.CAcert.org/ --load-chain chain.pem
264

EXIT STATUS

266       One of the following exit values will be returned:
267
268       0  (EXIT_SUCCESS)
269              Successful program execution.
270
271       1  (EXIT_FAILURE)
272              The operation failed or the command syntax was not valid.
273

SEE ALSO

275       certtool (1)
276

AUTHORS

279       Copyright (C) 2020-2023 Free Software Foundation, and others all rights
280       reserved.  This program is released under the terms of the GNU General
281       Public License, version 3 or later
282

BUGS

284       Please send bug reports to: bugs@gnutls.org
285
286
287
2883.8.2                             15 Nov 2023                      ocsptool(1)
Impressum