1ocsptool(1) User Commands ocsptool(1)
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6 ocsptool - GnuTLS OCSP tool
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9 ocsptool [-flags] [-flag [value]] [--option-name[[=| ]value]]
10 All arguments must be options.
12
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
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 Specifies the debug level.
30 -V, --verbose
32 More verbose output.
33 --infile=file
36 Input file.
37 --outfile=str
40 Output file.
41 --ask=server name|url
44 Ask an OCSP/HTTP server on a certificate validity.
45 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 -e, --verify-response
54 Verify response.
55 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 -i, --request-info
62 Print information on a OCSP request.
63 Display detailed information on the provided OCSP request.
65 -j, --response-info
67 Print information on a OCSP response.
68 Display detailed information on the provided OCSP response.
70 -q, --generate-request
72 Generates an OCSP request.
73 --nonce, --no-nonce
76 Use (or not) a nonce to OCSP request. The no-nonce form will
77 disable the option.
78 --load-chain=file
81 Reads a set of certificates forming a chain from file.
82 --load-issuer=file
85 Reads issuer's certificate from file.
86 --load-cert=file
89 Reads the certificate to check from file.
90 --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 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 --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 --inder, --no-inder
107 Use DER format for input certificates and private keys. The
108 no-inder form will disable the option.
109 --outder
112 Use DER format for output of responses (this is the default).
113 The output will be in DER encoded format. Unlike other GnuTLS
115 tools, this is the default for this tool
116 --outpem
118 Use PEM format for output of responses.
119 The output will be in PEM format.
121 -Q file, --load-request=file
123 Reads the DER encoded OCSP request from file.
124 -S file, --load-response=file
127 Reads the DER encoded OCSP response from file.
128 --ignore-errors
131 Ignore any verification errors.
132 --verify-allow-broken
135 Allow broken algorithms, such as MD5 for verification.
136 This can be combined with --verify-response.
138 -v arg, --version=arg
140 Output version of program and exit. The default mode is `v', a
141 simple version. The `c' mode will print copyright information
142 and `n' will print the full copyright notice.
143 -h, --help
145 Display usage information and exit.
146 -!, --more-help
148 Pass the extended usage information through a pager.
149
153 Print information about an OCSP request
154 To parse an OCSP request and print information about the content, the
156 -i or --request-info parameter may be used as follows. The -Q parame‐
157 ter specify the name of the file containing the OCSP request, and it
158 should contain the OCSP request in binary DER format.
159 $ ocsptool -i -Q ocsp-request.der
161 The input file may also be sent to standard input like this:
163 $ cat ocsp-request.der | ocsptool --request-info
165 Print information about an OCSP response
167 Similar to parsing OCSP requests, OCSP responses can be parsed using
169 the -j or --response-info as follows.
170 $ ocsptool -j -Q ocsp-response.der
172 $ cat ocsp-response.der | ocsptool --response-info
173 Generate an OCSP request
175 The -q or --generate-request parameters are used to generate an OCSP
177 request. By default the OCSP request is written to standard output in
178 binary DER format, but can be stored in a file using --outfile. To
179 generate an OCSP request the issuer of the certificate to check needs
180 to be specified with --load-issuer and the certificate to check with
181 --load-cert. By default PEM format is used for these files, although
182 --inder can be used to specify that the input files are in DER format.
183 $ ocsptool -q --load-issuer issuer.pem --load-cert client.pem --outfile ocsp-request.der
185 When generating OCSP requests, the tool will add an OCSP extension con‐
187 taining a nonce. This behaviour can be disabled by specifying
188 --no-nonce.
189 Verify signature in OCSP response
191 To verify the signature in an OCSP response the -e or --verify-response
193 parameter is used. The tool will read an OCSP response in DER format
194 from standard input, or from the file specified by --load-response.
195 The OCSP response is verified against a set of trust anchors, which are
196 specified using --load-trust. The trust anchors are concatenated cer‐
197 tificates in PEM format. The certificate that signed the OCSP response
198 needs to be in the set of trust anchors, or the issuer of the signer
199 certificate needs to be in the set of trust anchors and the OCSP Ex‐
200 tended Key Usage bit has to be asserted in the signer certificate.
201 $ ocsptool -e --load-trust issuer.pem --load-response ocsp-response.der
203 The tool will print status of verification.
205 Verify signature in OCSP response against given certificate
207 It is possible to override the normal trust logic if you know that a
209 certain certificate is supposed to have signed the OCSP response, and
210 you want to use it to check the signature. This is achieved using
211 --load-signer instead of --load-trust. This will load one certificate
212 and it will be used to verify the signature in the OCSP response. It
213 will not check the Extended Key Usage bit.
214 $ ocsptool -e --load-signer ocsp-signer.pem --load-response ocsp-response.der
216 This approach is normally only relevant in two situations. The first
218 is when the OCSP response does not contain a copy of the signer cer‐
219 tificate, so the --load-trust code would fail. The second is if you
220 want to avoid the indirect mode where the OCSP response signer certifi‐
221 cate is signed by a trust anchor.
222 Real-world example
224 Here is an example of how to generate an OCSP request for a certificate
226 and to verify the response. For illustration we'll use the blog.josef‐
227 sson.org host, which (as of writing) uses a certificate from CACert.
228 First we'll use gnutls-cli to get a copy of the server certificate
229 chain. The server is not required to send this information, but this
230 particular one is configured to do so.
231 $ echo | gnutls-cli -p 443 blog.josefsson.org --save-cert chain.pem
233 The saved certificates normally contain a pointer to where the OCSP re‐
235 sponder is located, in the Authority Information Access Information ex‐
236 tension. For example, from certtool -i < chain.pem there is this in‐
237 formation:
238 Authority Information Access Information (not critical):
240 Access Method: 1.3.6.1.5.5.7.48.1 (id-ad-ocsp)
241 Access Location URI: https://ocsp.CAcert.org/
242 This means that ocsptool can discover the servers to contact over HTTP.
244 We can now request information on the chain certificates.
245 $ ocsptool --ask --load-chain chain.pem
247 The request is sent via HTTP to the OCSP server address found in the
249 certificates. It is possible to override the address of the OCSP server
250 as well as ask information on a particular certificate using
251 --load-cert and --load-issuer.
252 $ ocsptool --ask https://ocsp.CAcert.org/ --load-chain chain.pem
254
256 One of the following exit values will be returned:
257 0 (EXIT_SUCCESS)
259 Successful program execution.
260 1 (EXIT_FAILURE)
262 The operation failed or the command syntax was not valid.
263
265 certtool (1)
266
269 Copyright (C) 2020-2021 Free Software Foundation, and others all rights
270 reserved. This program is released under the terms of the GNU General
271 Public License, version 3 or later
272
274 Please send bug reports to: bugs@gnutls.org
2753.7.6 27 May 2022 ocsptool(1)