5 ocsp - Online Certificate Status Protocol utility
32 [B<-attime timestamp>]
52 [B<-verify_depth num>]
53 [B<-verify_email email>]
54 [B<-verify_hostname hostname>]
56 [B<-verify_name name>]
59 [B<-validity_period n>]
62 [B<-verify_other file>]
65 [B<-no_signature_verify>]
84 The Online Certificate Status Protocol (OCSP) enables applications to
85 determine the (revocation) state of an identified certificate (RFC 2560).
87 The B<ocsp> command performs many common OCSP tasks. It can be used
88 to print out requests and responses, create requests and send queries
89 to an OCSP responder and behave like a mini OCSP server itself.
91 =head1 OCSP CLIENT OPTIONS
95 =item B<-out filename>
97 specify output filename, default is standard output.
99 =item B<-issuer filename>
101 This specifies the current issuer certificate. This option can be used
102 multiple times. The certificate specified in B<filename> must be in
103 PEM format. This option B<MUST> come before any B<-cert> options.
105 =item B<-cert filename>
107 Add the certificate B<filename> to the request. The issuer certificate
108 is taken from the previous B<issuer> option, or an error occurs if no
109 issuer certificate is specified.
113 Same as the B<cert> option except the certificate with serial number
114 B<num> is added to the request. The serial number is interpreted as a
115 decimal integer unless preceded by B<0x>. Negative integers can also
116 be specified by preceding the value by a B<-> sign.
118 =item B<-signer filename>, B<-signkey filename>
120 Sign the OCSP request using the certificate specified in the B<signer>
121 option and the private key specified by the B<signkey> option. If
122 the B<signkey> option is not present then the private key is read
123 from the same file as the certificate. If neither option is specified then
124 the OCSP request is not signed.
126 =item B<-sign_other filename>
128 Additional certificates to include in the signed request.
130 =item B<-nonce>, B<-no_nonce>
132 Add an OCSP nonce extension to a request or disable OCSP nonce addition.
133 Normally if an OCSP request is input using the B<respin> option no
134 nonce is added: using the B<nonce> option will force addition of a nonce.
135 If an OCSP request is being created (using B<cert> and B<serial> options)
136 a nonce is automatically added specifying B<no_nonce> overrides this.
138 =item B<-req_text>, B<-resp_text>, B<-text>
140 print out the text form of the OCSP request, response or both respectively.
142 =item B<-reqout file>, B<-respout file>
144 write out the DER encoded certificate request or response to B<file>.
146 =item B<-reqin file>, B<-respin file>
148 read OCSP request or response file from B<file>. These option are ignored
149 if OCSP request or response creation is implied by other options (for example
150 with B<serial>, B<cert> and B<host> options).
152 =item B<-url responder_url>
154 specify the responder URL. Both HTTP and HTTPS (SSL/TLS) URLs can be specified.
156 =item B<-host hostname:port>, B<-path pathname>
158 if the B<host> option is present then the OCSP request is sent to the host
159 B<hostname> on port B<port>. B<path> specifies the HTTP path name to use
162 =item B<-CAfile file>, B<-CApath pathname>
164 file or pathname containing trusted CA certificates. These are used to verify
165 the signature on the OCSP response.
167 =item B<-attime>, B<-check_ss_sig>, B<-crl_check>, B<-crl_check_all>,
168 B<explicit_policy>, B<-extended_crl>, B<-ignore_critical>, B<-inhibit_any>,
169 B<-inhibit_map>, B<-issuer_checks>, B<-partial_chain>, B<-policy>,
170 B<-policy_check>, B<-policy_print>, B<-purpose>, B<-suiteB_128>,
171 B<-suiteB_128_only>, B<-suiteB_192>, B<-trusted_first>, B<-use_deltas>,
172 B<-verify_depth>, B<-verify_email>, B<-verify_hostname>, B<-verify_ip>,
173 B<-verify_name>, B<-x509_strict>
175 Set different certificate verification options.
176 See L<B<verify>|verify(1)> manual page for details.
178 =item B<-verify_other file>
180 file containing additional certificates to search when attempting to locate
181 the OCSP response signing certificate. Some responders omit the actual signer's
182 certificate from the response: this option can be used to supply the necessary
183 certificate in such cases.
185 =item B<-trust_other>
187 the certificates specified by the B<-verify_other> option should be explicitly
188 trusted and no additional checks will be performed on them. This is useful
189 when the complete responder certificate chain is not available or trusting a
190 root CA is not appropriate.
192 =item B<-VAfile file>
194 file containing explicitly trusted responder certificates. Equivalent to the
195 B<-verify_other> and B<-trust_other> options.
199 don't attempt to verify the OCSP response signature or the nonce values. This
200 option will normally only be used for debugging since it disables all verification
201 of the responders certificate.
205 ignore certificates contained in the OCSP response when searching for the
206 signers certificate. With this option the signers certificate must be specified
207 with either the B<-verify_other> or B<-VAfile> options.
209 =item B<-no_signature_verify>
211 don't check the signature on the OCSP response. Since this option tolerates invalid
212 signatures on OCSP responses it will normally only be used for testing purposes.
214 =item B<-no_cert_verify>
216 don't verify the OCSP response signers certificate at all. Since this option allows
217 the OCSP response to be signed by any certificate it should only be used for
222 do not use certificates in the response as additional untrusted CA
225 =item B<-no_cert_checks>
227 don't perform any additional checks on the OCSP response signers certificate.
228 That is do not make any checks to see if the signers certificate is authorised
229 to provide the necessary status information: as a result this option should
230 only be used for testing purposes.
232 =item B<-validity_period nsec>, B<-status_age age>
234 these options specify the range of times, in seconds, which will be tolerated
235 in an OCSP response. Each certificate status response includes a B<notBefore> time and
236 an optional B<notAfter> time. The current time should fall between these two values, but
237 the interval between the two times may be only a few seconds. In practice the OCSP
238 responder and clients clocks may not be precisely synchronised and so such a check
239 may fail. To avoid this the B<-validity_period> option can be used to specify an
240 acceptable error range in seconds, the default value is 5 minutes.
242 If the B<notAfter> time is omitted from a response then this means that new status
243 information is immediately available. In this case the age of the B<notBefore> field
244 is checked to see it is not older than B<age> seconds old. By default this additional
245 check is not performed.
247 =item B<-md5|-sha1|-sha256|-ripemod160|...>
249 this option sets digest algorithm to use for certificate identification
250 in the OCSP request. By default SHA-1 is used.
254 =head1 OCSP SERVER OPTIONS
258 =item B<-index indexfile>
260 B<indexfile> is a text index file in B<ca> format containing certificate revocation
263 If the B<index> option is specified the B<ocsp> utility is in responder mode, otherwise
264 it is in client mode. The request(s) the responder processes can be either specified on
265 the command line (using B<issuer> and B<serial> options), supplied in a file (using the
266 B<respin> option) or via external OCSP clients (if B<port> or B<url> is specified).
268 If the B<index> option is present then the B<CA> and B<rsigner> options must also be
273 CA certificate corresponding to the revocation information in B<indexfile>.
275 =item B<-rsigner file>
277 The certificate to sign OCSP responses with.
279 =item B<-rother file>
281 Additional certificates to include in the OCSP response.
283 =item B<-resp_no_certs>
285 Don't include any certificates in the OCSP response.
287 =item B<-resp_key_id>
289 Identify the signer certificate using the key ID, default is to use the subject name.
293 The private key to sign OCSP responses with: if not present the file specified in the
294 B<rsigner> option is used.
296 =item B<-port portnum>
298 Port to listen for OCSP requests on. The port may also be specified using the B<url>
301 =item B<-nrequest number>
303 The OCSP server will exit after receiving B<number> requests, default unlimited.
305 =item B<-nmin minutes>, B<-ndays days>
307 Number of minutes or days when fresh revocation information is available: used in the
308 B<nextUpdate> field. If neither option is present then the B<nextUpdate> field is
309 omitted meaning fresh revocation information is immediately available.
313 =head1 OCSP Response verification.
315 OCSP Response follows the rules specified in RFC2560.
317 Initially the OCSP responder certificate is located and the signature on
318 the OCSP request checked using the responder certificate's public key.
320 Then a normal certificate verify is performed on the OCSP responder certificate
321 building up a certificate chain in the process. The locations of the trusted
322 certificates used to build the chain can be specified by the B<CAfile>
323 and B<CApath> options or they will be looked for in the standard OpenSSL
324 certificates directory.
326 If the initial verify fails then the OCSP verify process halts with an
329 Otherwise the issuing CA certificate in the request is compared to the OCSP
330 responder certificate: if there is a match then the OCSP verify succeeds.
332 Otherwise the OCSP responder certificate's CA is checked against the issuing
333 CA certificate in the request. If there is a match and the OCSPSigning
334 extended key usage is present in the OCSP responder certificate then the
335 OCSP verify succeeds.
337 Otherwise the root CA of the OCSP responders CA is checked to see if it
338 is trusted for OCSP signing. If it is the OCSP verify succeeds.
340 If none of these checks is successful then the OCSP verify fails.
342 What this effectively means if that if the OCSP responder certificate is
343 authorised directly by the CA it is issuing revocation information about
344 (and it is correctly configured) then verification will succeed.
346 If the OCSP responder is a "global responder" which can give details about
347 multiple CAs and has its own separate certificate chain then its root
348 CA can be trusted for OCSP signing. For example:
350 openssl x509 -in ocspCA.pem -addtrust OCSPSigning -out trustedCA.pem
352 Alternatively the responder certificate itself can be explicitly trusted
353 with the B<-VAfile> option.
357 As noted, most of the verify options are for testing or debugging purposes.
358 Normally only the B<-CApath>, B<-CAfile> and (if the responder is a 'global
359 VA') B<-VAfile> options need to be used.
361 The OCSP server is only useful for test and demonstration purposes: it is
362 not really usable as a full OCSP responder. It contains only a very
363 simple HTTP request handling and can only handle the POST form of OCSP
364 queries. It also handles requests serially meaning it cannot respond to
365 new requests until it has processed the current one. The text index file
366 format of revocation is also inefficient for large quantities of revocation
369 It is possible to run the B<ocsp> application in responder mode via a CGI
370 script using the B<respin> and B<respout> options.
374 Create an OCSP request and write it to a file:
376 openssl ocsp -issuer issuer.pem -cert c1.pem -cert c2.pem -reqout req.der
378 Send a query to an OCSP responder with URL http://ocsp.myhost.com/ save the
379 response to a file and print it out in text form
381 openssl ocsp -issuer issuer.pem -cert c1.pem -cert c2.pem \
382 -url http://ocsp.myhost.com/ -resp_text -respout resp.der
384 Read in an OCSP response and print out text form:
386 openssl ocsp -respin resp.der -text
388 OCSP server on port 8888 using a standard B<ca> configuration, and a separate
389 responder certificate. All requests and responses are printed to a file.
391 openssl ocsp -index demoCA/index.txt -port 8888 -rsigner rcert.pem -CA demoCA/cacert.pem
394 As above but exit after processing one request:
396 openssl ocsp -index demoCA/index.txt -port 8888 -rsigner rcert.pem -CA demoCA/cacert.pem
399 Query status information using internally generated request:
401 openssl ocsp -index demoCA/index.txt -rsigner rcert.pem -CA demoCA/cacert.pem
402 -issuer demoCA/cacert.pem -serial 1
404 Query status information using request read from a file, write response to a
407 openssl ocsp -index demoCA/index.txt -rsigner rcert.pem -CA demoCA/cacert.pem
408 -reqin req.der -respout resp.der