1REQ(1) OpenSSL REQ(1)
2
6 openssl-req, req - PKCS#10 certificate request and certificate
7 generating utility
8
10 openssl req [-help] [-inform PEM|DER] [-outform PEM|DER] [-in filename]
11 [-passin arg] [-out filename] [-passout arg] [-text] [-pubkey] [-noout]
12 [-verify] [-modulus] [-new] [-rand file...] [-writerand file] [-newkey
13 rsa:bits] [-newkey alg:file] [-nodes] [-key filename] [-keyform
14 PEM|DER] [-keyout filename] [-keygen_engine id] [-digest] [-config
15 filename] [-multivalue-rdn] [-x509] [-days n] [-set_serial n] [-newhdr]
16 [-addext ext] [-extensions section] [-reqexts section] [-precert]
17 [-utf8] [-nameopt] [-reqopt] [-subject] [-subj arg] [-batch] [-verbose]
18 [-engine id]
19
21 The req command primarily creates and processes certificate requests in
22 PKCS#10 format. It can additionally create self signed certificates for
23 use as root CAs for example.
24
26 -help
27 Print out a usage message.
28 -inform DER|PEM
30 This specifies the input format. The DER option uses an ASN1 DER
31 encoded form compatible with the PKCS#10. The PEM form is the
32 default format: it consists of the DER format base64 encoded with
33 additional header and footer lines.
34 -outform DER|PEM
36 This specifies the output format, the options have the same meaning
37 and default as the -inform option.
38 -in filename
40 This specifies the input filename to read a request from or
41 standard input if this option is not specified. A request is only
42 read if the creation options (-new and -newkey) are not specified.
43 -passin arg
45 The input file password source. For more information about the
46 format of arg see the PASS PHRASE ARGUMENTS section in openssl(1).
47 -out filename
49 This specifies the output filename to write to or standard output
50 by default.
51 -passout arg
53 The output file password source. For more information about the
54 format of arg see the PASS PHRASE ARGUMENTS section in openssl(1).
55 -text
57 Prints out the certificate request in text form.
58 -subject
60 Prints out the request subject (or certificate subject if -x509 is
61 specified)
62 -pubkey
64 Outputs the public key.
65 -noout
67 This option prevents output of the encoded version of the request.
68 -modulus
70 This option prints out the value of the modulus of the public key
71 contained in the request.
72 -verify
74 Verifies the signature on the request.
75 -new
77 This option generates a new certificate request. It will prompt the
78 user for the relevant field values. The actual fields prompted for
79 and their maximum and minimum sizes are specified in the
80 configuration file and any requested extensions.
81 If the -key option is not used it will generate a new RSA private
83 key using information specified in the configuration file.
84 -rand file...
86 A file or files containing random data used to seed the random
87 number generator. Multiple files can be specified separated by an
88 OS-dependent character. The separator is ; for MS-Windows, , for
89 OpenVMS, and : for all others.
90 [-writerand file]
92 Writes random data to the specified file upon exit. This can be
93 used with a subsequent -rand flag.
94 -newkey arg
96 This option creates a new certificate request and a new private
97 key. The argument takes one of several forms. rsa:nbits, where
98 nbits is the number of bits, generates an RSA key nbits in size. If
99 nbits is omitted, i.e. -newkey rsa specified, the default key size,
100 specified in the configuration file is used.
101 All other algorithms support the -newkey alg:file form, where file
103 may be an algorithm parameter file, created by the genpkey
104 -genparam command or and X.509 certificate for a key with
105 appropriate algorithm.
106 param:file generates a key using the parameter file or certificate
108 file, the algorithm is determined by the parameters. algname:file
109 use algorithm algname and parameter file file: the two algorithms
110 must match or an error occurs. algname just uses algorithm algname,
111 and parameters, if necessary should be specified via -pkeyopt
112 parameter.
113 dsa:filename generates a DSA key using the parameters in the file
115 filename. ec:filename generates EC key (usable both with ECDSA or
116 ECDH algorithms), gost2001:filename generates GOST R 34.10-2001 key
117 (requires ccgost engine configured in the configuration file). If
118 just gost2001 is specified a parameter set should be specified by
119 -pkeyopt paramset:X
120 -pkeyopt opt:value
122 Set the public key algorithm option opt to value. The precise set
123 of options supported depends on the public key algorithm used and
124 its implementation. See KEY GENERATION OPTIONS in the genpkey
125 manual page for more details.
126 -key filename
128 This specifies the file to read the private key from. It also
129 accepts PKCS#8 format private keys for PEM format files.
130 -keyform PEM|DER
132 The format of the private key file specified in the -key argument.
133 PEM is the default.
134 -keyout filename
136 This gives the filename to write the newly created private key to.
137 If this option is not specified then the filename present in the
138 configuration file is used.
139 -nodes
141 If this option is specified then if a private key is created it
142 will not be encrypted.
143 -digest
145 This specifies the message digest to sign the request. Any digest
146 supported by the OpenSSL dgst command can be used. This overrides
147 the digest algorithm specified in the configuration file.
148 Some public key algorithms may override this choice. For instance,
150 DSA signatures always use SHA1, GOST R 34.10 signatures always use
151 GOST R 34.11-94 (-md_gost94), Ed25519 and Ed448 never use any
152 digest.
153 -config filename
155 This allows an alternative configuration file to be specified.
156 Optional; for a description of the default value, see "COMMAND
157 SUMMARY" in openssl(1).
158 -subj arg
160 Sets subject name for new request or supersedes the subject name
161 when processing a request. The arg must be formatted as
162 /type0=value0/type1=value1/type2=..., characters may be escaped by
163 \ (backslash), no spaces are skipped.
164 -multivalue-rdn
166 This option causes the -subj argument to be interpreted with full
167 support for multivalued RDNs. Example:
168 /DC=org/DC=OpenSSL/DC=users/UID=123456+CN=John Doe
170 If -multi-rdn is not used then the UID value is 123456+CN=John Doe.
172 -x509
174 This option outputs a self signed certificate instead of a
175 certificate request. This is typically used to generate a test
176 certificate or a self signed root CA. The extensions added to the
177 certificate (if any) are specified in the configuration file.
178 Unless specified using the set_serial option, a large random number
179 will be used for the serial number.
180 If existing request is specified with the -in option, it is
182 converted to the self signed certificate otherwise new request is
183 created.
184 -days n
186 When the -x509 option is being used this specifies the number of
187 days to certify the certificate for, otherwise it is ignored. n
188 should be a positive integer. The default is 30 days.
189 -set_serial n
191 Serial number to use when outputting a self signed certificate.
192 This may be specified as a decimal value or a hex value if preceded
193 by 0x.
194 -addext ext
196 Add a specific extension to the certificate (if the -x509 option is
197 present) or certificate request. The argument must have the form
198 of a key=value pair as it would appear in a config file.
199 This option can be given multiple times.
201 -extensions section
203 -reqexts section
204 These options specify alternative sections to include certificate
205 extensions (if the -x509 option is present) or certificate request
206 extensions. This allows several different sections to be used in
207 the same configuration file to specify requests for a variety of
208 purposes.
209 -precert
211 A poison extension will be added to the certificate, making it a
212 "pre-certificate" (see RFC6962). This can be submitted to
213 Certificate Transparency logs in order to obtain signed certificate
214 timestamps (SCTs). These SCTs can then be embedded into the pre-
215 certificate as an extension, before removing the poison and signing
216 the certificate.
217 This implies the -new flag.
219 -utf8
221 This option causes field values to be interpreted as UTF8 strings,
222 by default they are interpreted as ASCII. This means that the field
223 values, whether prompted from a terminal or obtained from a
224 configuration file, must be valid UTF8 strings.
225 -nameopt option
227 Option which determines how the subject or issuer names are
228 displayed. The option argument can be a single option or multiple
229 options separated by commas. Alternatively the -nameopt switch may
230 be used more than once to set multiple options. See the x509(1)
231 manual page for details.
232 -reqopt
234 Customise the output format used with -text. The option argument
235 can be a single option or multiple options separated by commas.
236 See discussion of the -certopt parameter in the x509(1) command.
238 -newhdr
240 Adds the word NEW to the PEM file header and footer lines on the
241 outputted request. Some software (Netscape certificate server) and
242 some CAs need this.
243 -batch
245 Non-interactive mode.
246 -verbose
248 Print extra details about the operations being performed.
249 -engine id
251 Specifying an engine (by its unique id string) will cause req to
252 attempt to obtain a functional reference to the specified engine,
253 thus initialising it if needed. The engine will then be set as the
254 default for all available algorithms.
255 -keygen_engine id
257 Specifies an engine (by its unique id string) which would be used
258 for key generation operations.
259
261 The configuration options are specified in the req section of the
262 configuration file. As with all configuration files if no value is
263 specified in the specific section (i.e. req) then the initial unnamed
264 or default section is searched too.
265 The options available are described in detail below.
267 input_password output_password
269 The passwords for the input private key file (if present) and the
270 output private key file (if one will be created). The command line
271 options passin and passout override the configuration file values.
272 default_bits
274 Specifies the default key size in bits.
275 This option is used in conjunction with the -new option to generate
277 a new key. It can be overridden by specifying an explicit key size
278 in the -newkey option. The smallest accepted key size is 512 bits.
279 If no key size is specified then 2048 bits is used.
280 default_keyfile
282 This is the default filename to write a private key to. If not
283 specified the key is written to standard output. This can be
284 overridden by the -keyout option.
285 oid_file
287 This specifies a file containing additional OBJECT IDENTIFIERS.
288 Each line of the file should consist of the numerical form of the
289 object identifier followed by white space then the short name
290 followed by white space and finally the long name.
291 oid_section
293 This specifies a section in the configuration file containing extra
294 object identifiers. Each line should consist of the short name of
295 the object identifier followed by = and the numerical form. The
296 short and long names are the same when this option is used.
297 RANDFILE
299 At startup the specified file is loaded into the random number
300 generator, and at exit 256 bytes will be written to it. It is used
301 for private key generation.
302 encrypt_key
304 If this is set to no then if a private key is generated it is not
305 encrypted. This is equivalent to the -nodes command line option.
306 For compatibility encrypt_rsa_key is an equivalent option.
307 default_md
309 This option specifies the digest algorithm to use. Any digest
310 supported by the OpenSSL dgst command can be used. This option can
311 be overridden on the command line. Certain signing algorithms (i.e.
312 Ed25519 and Ed448) will ignore any digest that has been set.
313 string_mask
315 This option masks out the use of certain string types in certain
316 fields. Most users will not need to change this option.
317 It can be set to several values default which is also the default
319 option uses PrintableStrings, T61Strings and BMPStrings if the pkix
320 value is used then only PrintableStrings and BMPStrings will be
321 used. This follows the PKIX recommendation in RFC2459. If the
322 utf8only option is used then only UTF8Strings will be used: this is
323 the PKIX recommendation in RFC2459 after 2003. Finally the nombstr
324 option just uses PrintableStrings and T61Strings: certain software
325 has problems with BMPStrings and UTF8Strings: in particular
326 Netscape.
327 req_extensions
329 This specifies the configuration file section containing a list of
330 extensions to add to the certificate request. It can be overridden
331 by the -reqexts command line switch. See the x509v3_config(5)
332 manual page for details of the extension section format.
333 x509_extensions
335 This specifies the configuration file section containing a list of
336 extensions to add to certificate generated when the -x509 switch is
337 used. It can be overridden by the -extensions command line switch.
338 prompt
340 If set to the value no this disables prompting of certificate
341 fields and just takes values from the config file directly. It also
342 changes the expected format of the distinguished_name and
343 attributes sections.
344 utf8
346 If set to the value yes then field values to be interpreted as UTF8
347 strings, by default they are interpreted as ASCII. This means that
348 the field values, whether prompted from a terminal or obtained from
349 a configuration file, must be valid UTF8 strings.
350 attributes
352 This specifies the section containing any request attributes: its
353 format is the same as distinguished_name. Typically these may
354 contain the challengePassword or unstructuredName types. They are
355 currently ignored by OpenSSL's request signing utilities but some
356 CAs might want them.
357 distinguished_name
359 This specifies the section containing the distinguished name fields
360 to prompt for when generating a certificate or certificate request.
361 The format is described in the next section.
362
364 There are two separate formats for the distinguished name and attribute
365 sections. If the prompt option is set to no then these sections just
366 consist of field names and values: for example,
367 CN=My Name
369 OU=My Organization
370 emailAddress=someone@somewhere.org
371 This allows external programs (e.g. GUI based) to generate a template
373 file with all the field names and values and just pass it to req. An
374 example of this kind of configuration file is contained in the EXAMPLES
375 section.
376 Alternatively if the prompt option is absent or not set to no then the
378 file contains field prompting information. It consists of lines of the
379 form:
380 fieldName="prompt"
382 fieldName_default="default field value"
383 fieldName_min= 2
384 fieldName_max= 4
385 "fieldName" is the field name being used, for example commonName (or
387 CN). The "prompt" string is used to ask the user to enter the relevant
388 details. If the user enters nothing then the default value is used if
389 no default value is present then the field is omitted. A field can
390 still be omitted if a default value is present if the user just enters
391 the '.' character.
392 The number of characters entered must be between the fieldName_min and
394 fieldName_max limits: there may be additional restrictions based on the
395 field being used (for example countryName can only ever be two
396 characters long and must fit in a PrintableString).
397 Some fields (such as organizationName) can be used more than once in a
399 DN. This presents a problem because configuration files will not
400 recognize the same name occurring twice. To avoid this problem if the
401 fieldName contains some characters followed by a full stop they will be
402 ignored. So for example a second organizationName can be input by
403 calling it "1.organizationName".
404 The actual permitted field names are any object identifier short or
406 long names. These are compiled into OpenSSL and include the usual
407 values such as commonName, countryName, localityName, organizationName,
408 organizationalUnitName, stateOrProvinceName. Additionally emailAddress
409 is include as well as name, surname, givenName initials and
410 dnQualifier.
411 Additional object identifiers can be defined with the oid_file or
413 oid_section options in the configuration file. Any additional fields
414 will be treated as though they were a DirectoryString.
415
417 Examine and verify certificate request:
418 openssl req -in req.pem -text -verify -noout
420 Create a private key and then generate a certificate request from it:
422 openssl genrsa -out key.pem 2048
424 openssl req -new -key key.pem -out req.pem
425 The same but just using req:
427 openssl req -newkey rsa:2048 -keyout key.pem -out req.pem
429 Generate a self signed root certificate:
431 openssl req -x509 -newkey rsa:2048 -keyout key.pem -out req.pem
433 Example of a file pointed to by the oid_file option:
435 1.2.3.4 shortName A longer Name
437 1.2.3.6 otherName Other longer Name
438 Example of a section pointed to by oid_section making use of variable
440 expansion:
441 testoid1=1.2.3.5
443 testoid2=${testoid1}.6
444 Sample configuration file prompting for field values:
446 [ req ]
448 default_bits = 2048
449 default_keyfile = privkey.pem
450 distinguished_name = req_distinguished_name
451 attributes = req_attributes
452 req_extensions = v3_ca
453 dirstring_type = nobmp
455 [ req_distinguished_name ]
457 countryName = Country Name (2 letter code)
458 countryName_default = AU
459 countryName_min = 2
460 countryName_max = 2
461 localityName = Locality Name (eg, city)
463 organizationalUnitName = Organizational Unit Name (eg, section)
465 commonName = Common Name (eg, YOUR name)
467 commonName_max = 64
468 emailAddress = Email Address
470 emailAddress_max = 40
471 [ req_attributes ]
473 challengePassword = A challenge password
474 challengePassword_min = 4
475 challengePassword_max = 20
476 [ v3_ca ]
478 subjectKeyIdentifier=hash
480 authorityKeyIdentifier=keyid:always,issuer:always
481 basicConstraints = critical, CA:true
482 Sample configuration containing all field values:
484 RANDFILE = $ENV::HOME/.rnd
486 [ req ]
488 default_bits = 2048
489 default_keyfile = keyfile.pem
490 distinguished_name = req_distinguished_name
491 attributes = req_attributes
492 prompt = no
493 output_password = mypass
494 [ req_distinguished_name ]
496 C = GB
497 ST = Test State or Province
498 L = Test Locality
499 O = Organization Name
500 OU = Organizational Unit Name
501 CN = Common Name
502 emailAddress = test@email.address
503 [ req_attributes ]
505 challengePassword = A challenge password
506 Example of giving the most common attributes (subject and extensions)
508 on the command line:
509 openssl req -new -subj "/C=GB/CN=foo" \
511 -addext "subjectAltName = DNS:foo.co.uk" \
512 -addext "certificatePolicies = 1.2.3.4" \
513 -newkey rsa:2048 -keyout key.pem -out req.pem
514
516 The header and footer lines in the PEM format are normally:
517 -----BEGIN CERTIFICATE REQUEST-----
519 -----END CERTIFICATE REQUEST-----
520 some software (some versions of Netscape certificate server) instead
522 needs:
523 -----BEGIN NEW CERTIFICATE REQUEST-----
525 -----END NEW CERTIFICATE REQUEST-----
526 which is produced with the -newhdr option but is otherwise compatible.
528 Either form is accepted transparently on input.
529 The certificate requests generated by Xenroll with MSIE have extensions
531 added. It includes the keyUsage extension which determines the type of
532 key (signature only or general purpose) and any additional OIDs entered
533 by the script in an extendedKeyUsage extension.
534
536 The following messages are frequently asked about:
537 Using configuration from /some/path/openssl.cnf
539 Unable to load config info
540 This is followed some time later by...
542 unable to find 'distinguished_name' in config
544 problems making Certificate Request
545 The first error message is the clue: it can't find the configuration
547 file! Certain operations (like examining a certificate request) don't
548 need a configuration file so its use isn't enforced. Generation of
549 certificates or requests however does need a configuration file. This
550 could be regarded as a bug.
551 Another puzzling message is this:
553 Attributes:
555 a0:00
556 this is displayed when no attributes are present and the request
558 includes the correct empty SET OF structure (the DER encoding of which
559 is 0xa0 0x00). If you just see:
560 Attributes:
562 then the SET OF is missing and the encoding is technically invalid (but
564 it is tolerated). See the description of the command line option
565 -asn1-kludge for more information.
566
568 OpenSSL's handling of T61Strings (aka TeletexStrings) is broken: it
569 effectively treats them as ISO-8859-1 (Latin 1), Netscape and MSIE have
570 similar behaviour. This can cause problems if you need characters that
571 aren't available in PrintableStrings and you don't want to or can't use
572 BMPStrings.
573 As a consequence of the T61String handling the only correct way to
575 represent accented characters in OpenSSL is to use a BMPString:
576 unfortunately Netscape currently chokes on these. If you have to use
577 accented characters with Netscape and MSIE then you currently need to
578 use the invalid T61String form.
579 The current prompting is not very friendly. It doesn't allow you to
581 confirm what you've just entered. Other things like extensions in
582 certificate requests are statically defined in the configuration file.
583 Some of these: like an email address in subjectAltName should be input
584 by the user.
585
587 x509(1), ca(1), genrsa(1), gendsa(1), config(5), x509v3_config(5)
588
590 Copyright 2000-2018 The OpenSSL Project Authors. All Rights Reserved.
591 Licensed under the OpenSSL license (the "License"). You may not use
593 this file except in compliance with the License. You can obtain a copy
594 in the file LICENSE in the source distribution or at
595 <https://www.openssl.org/source/license.html>.
5961.1.1 2018-09-11 REQ(1)