5 req - PKCS#10 certificate request and certificate generating utility
30 [B<-keygen_engine id>]
38 [B<-extensions section>]
52 The B<req> command primarily creates and processes certificate requests
53 in PKCS#10 format. It can additionally create self signed certificates
54 for use as root CAs for example.
62 Print out a usage message.
64 =item B<-inform DER|PEM>
66 This specifies the input format. The B<DER> option uses an ASN1 DER encoded
67 form compatible with the PKCS#10. The B<PEM> form is the default format: it
68 consists of the B<DER> format base64 encoded with additional header and
71 =item B<-outform DER|PEM>
73 This specifies the output format, the options have the same meaning as the
78 This specifies the input filename to read a request from or standard input
79 if this option is not specified. A request is only read if the creation
80 options (B<-new> and B<-newkey>) are not specified.
84 the input file password source. For more information about the format of B<arg>
85 see the B<PASS PHRASE ARGUMENTS> section in L<openssl(1)>.
87 =item B<-out filename>
89 This specifies the output filename to write to or standard output by
94 the output file password source. For more information about the format of B<arg>
95 see the B<PASS PHRASE ARGUMENTS> section in L<openssl(1)>.
99 prints out the certificate request in text form.
103 prints out the request subject (or certificate subject if B<-x509> is
108 outputs the public key.
112 this option prevents output of the encoded version of the request.
116 this option prints out the value of the modulus of the public key
117 contained in the request.
121 verifies the signature on the request.
125 this option generates a new certificate request. It will prompt
126 the user for the relevant field values. The actual fields
127 prompted for and their maximum and minimum sizes are specified
128 in the configuration file and any requested extensions.
130 If the B<-key> option is not used it will generate a new RSA private
131 key using information specified in the configuration file.
133 =item B<-rand file(s)>
135 a file or files containing random data used to seed the random number
136 generator, or an EGD socket (see L<RAND_egd(3)>).
137 Multiple files can be specified separated by an OS-dependent character.
138 The separator is B<;> for MS-Windows, B<,> for OpenVMS, and B<:> for
143 this option creates a new certificate request and a new private
144 key. The argument takes one of several forms. B<rsa:nbits>, where
145 B<nbits> is the number of bits, generates an RSA key B<nbits>
146 in size. If B<nbits> is omitted, i.e. B<-newkey rsa> specified,
147 the default key size, specified in the configuration file is used.
149 All other algorithms support the B<-newkey alg:file> form, where file may be
150 an algorithm parameter file, created by the B<genpkey -genparam> command
151 or and X.509 certificate for a key with appropriate algorithm.
153 B<param:file> generates a key using the parameter file or certificate B<file>,
154 the algorithm is determined by the parameters. B<algname:file> use algorithm
155 B<algname> and parameter file B<file>: the two algorithms must match or an
156 error occurs. B<algname> just uses algorithm B<algname>, and parameters,
157 if necessary should be specified via B<-pkeyopt> parameter.
159 B<dsa:filename> generates a DSA key using the parameters
160 in the file B<filename>. B<ec:filename> generates EC key (usable both with
161 ECDSA or ECDH algorithms), B<gost2001:filename> generates GOST R
162 34.10-2001 key (requires B<ccgost> engine configured in the configuration
163 file). If just B<gost2001> is specified a parameter set should be
164 specified by B<-pkeyopt paramset:X>
167 =item B<-pkeyopt opt:value>
169 set the public key algorithm option B<opt> to B<value>. The precise set of
170 options supported depends on the public key algorithm used and its
171 implementation. See B<KEY GENERATION OPTIONS> in the B<genpkey> manual page
174 =item B<-key filename>
176 This specifies the file to read the private key from. It also
177 accepts PKCS#8 format private keys for PEM format files.
179 =item B<-keyform PEM|DER>
181 the format of the private key file specified in the B<-key>
182 argument. PEM is the default.
184 =item B<-keyout filename>
186 this gives the filename to write the newly created private key to.
187 If this option is not specified then the filename present in the
188 configuration file is used.
192 if this option is specified then if a private key is created it
193 will not be encrypted.
197 this specifies the message digest to sign the request.
198 Any digest supported by the OpenSSL B<dgst> command can be used.
199 This overrides the digest algorithm specified in
200 the configuration file.
202 Some public key algorithms may override this choice. For instance, DSA
203 signatures always use SHA1, GOST R 34.10 signatures always use
204 GOST R 34.11-94 (B<-md_gost94>).
206 =item B<-config filename>
208 this allows an alternative configuration file to be specified.
209 Optional; for a description of the default value,
210 see L<openssl(1)/COMMAND SUMMARY>.
214 sets subject name for new request or supersedes the subject name
215 when processing a request.
216 The arg must be formatted as I</type0=value0/type1=value1/type2=...>,
217 characters may be escaped by \ (backslash), no spaces are skipped.
219 =item B<-multivalue-rdn>
221 this option causes the -subj argument to be interpreted with full
222 support for multivalued RDNs. Example:
224 I</DC=org/DC=OpenSSL/DC=users/UID=123456+CN=John Doe>
226 If -multi-rdn is not used then the UID value is I<123456+CN=John Doe>.
230 this option outputs a self signed certificate instead of a certificate
231 request. This is typically used to generate a test certificate or
232 a self signed root CA. The extensions added to the certificate
233 (if any) are specified in the configuration file. Unless specified
234 using the B<set_serial> option, a large random number will be used for
239 when the B<-x509> option is being used this specifies the number of
240 days to certify the certificate for. The default is 30 days.
242 =item B<-set_serial n>
244 serial number to use when outputting a self signed certificate. This
245 may be specified as a decimal value or a hex value if preceded by B<0x>.
247 =item B<-extensions section>
249 =item B<-reqexts section>
251 these options specify alternative sections to include certificate
252 extensions (if the B<-x509> option is present) or certificate
253 request extensions. This allows several different sections to
254 be used in the same configuration file to specify requests for
255 a variety of purposes.
259 a poison extension will be added to the certificate, making it a
260 "pre-certificate" (see RFC6962). This can be submitted to Certificate
261 Transparency logs in order to obtain signed certificate timestamps (SCTs).
262 These SCTs can then be embedded into the pre-certificate as an extension, before
263 removing the poison and signing the certificate.
267 this option causes field values to be interpreted as UTF8 strings, by
268 default they are interpreted as ASCII. This means that the field
269 values, whether prompted from a terminal or obtained from a
270 configuration file, must be valid UTF8 strings.
272 =item B<-nameopt option>
274 option which determines how the subject or issuer names are displayed. The
275 B<option> argument can be a single option or multiple options separated by
276 commas. Alternatively the B<-nameopt> switch may be used more than once to
277 set multiple options. See the L<x509(1)> manual page for details.
281 customise the output format used with B<-text>. The B<option> argument can be
282 a single option or multiple options separated by commas.
284 See discussion of the B<-certopt> parameter in the L<x509(1)>
289 Adds the word B<NEW> to the PEM file header and footer lines on the outputted
290 request. Some software (Netscape certificate server) and some CAs need this.
294 non-interactive mode.
298 print extra details about the operations being performed.
302 specifying an engine (by its unique B<id> string) will cause B<req>
303 to attempt to obtain a functional reference to the specified engine,
304 thus initialising it if needed. The engine will then be set as the default
305 for all available algorithms.
307 =item B<-keygen_engine id>
309 specifies an engine (by its unique B<id> string) which would be used
310 for key generation operations.
314 =head1 CONFIGURATION FILE FORMAT
316 The configuration options are specified in the B<req> section of
317 the configuration file. As with all configuration files if no
318 value is specified in the specific section (i.e. B<req>) then
319 the initial unnamed or B<default> section is searched too.
321 The options available are described in detail below.
325 =item B<input_password output_password>
327 The passwords for the input private key file (if present) and
328 the output private key file (if one will be created). The
329 command line options B<passin> and B<passout> override the
330 configuration file values.
332 =item B<default_bits>
334 Specifies the default key size in bits.
336 This option is used in conjunction with the B<-new> option to generate
337 a new key. It can be overridden by specifying an explicit key size in
338 the B<-newkey> option. The smallest accepted key size is 512 bits. If
339 no key size is specified then 2048 bits is used.
341 =item B<default_keyfile>
343 This is the default filename to write a private key to. If not
344 specified the key is written to standard output. This can be
345 overridden by the B<-keyout> option.
349 This specifies a file containing additional B<OBJECT IDENTIFIERS>.
350 Each line of the file should consist of the numerical form of the
351 object identifier followed by white space then the short name followed
352 by white space and finally the long name.
356 This specifies a section in the configuration file containing extra
357 object identifiers. Each line should consist of the short name of the
358 object identifier followed by B<=> and the numerical form. The short
359 and long names are the same when this option is used.
363 This specifies a filename in which random number seed information is
364 placed and read from, or an EGD socket (see L<RAND_egd(3)>).
365 It is used for private key generation.
369 If this is set to B<no> then if a private key is generated it is
370 B<not> encrypted. This is equivalent to the B<-nodes> command line
371 option. For compatibility B<encrypt_rsa_key> is an equivalent option.
375 This option specifies the digest algorithm to use.
376 Any digest supported by the OpenSSL B<dgst> command can be used.
377 If not present then MD5 is used.
378 This option can be overridden on the command line.
382 This option masks out the use of certain string types in certain
383 fields. Most users will not need to change this option.
385 It can be set to several values B<default> which is also the default
386 option uses PrintableStrings, T61Strings and BMPStrings if the
387 B<pkix> value is used then only PrintableStrings and BMPStrings will
388 be used. This follows the PKIX recommendation in RFC2459. If the
389 B<utf8only> option is used then only UTF8Strings will be used: this
390 is the PKIX recommendation in RFC2459 after 2003. Finally the B<nombstr>
391 option just uses PrintableStrings and T61Strings: certain software has
392 problems with BMPStrings and UTF8Strings: in particular Netscape.
394 =item B<req_extensions>
396 this specifies the configuration file section containing a list of
397 extensions to add to the certificate request. It can be overridden
398 by the B<-reqexts> command line switch. See the
399 L<x509v3_config(5)> manual page for details of the
400 extension section format.
402 =item B<x509_extensions>
404 this specifies the configuration file section containing a list of
405 extensions to add to certificate generated when the B<-x509> switch
406 is used. It can be overridden by the B<-extensions> command line switch.
410 if set to the value B<no> this disables prompting of certificate fields
411 and just takes values from the config file directly. It also changes the
412 expected format of the B<distinguished_name> and B<attributes> sections.
416 if set to the value B<yes> then field values to be interpreted as UTF8
417 strings, by default they are interpreted as ASCII. This means that
418 the field values, whether prompted from a terminal or obtained from a
419 configuration file, must be valid UTF8 strings.
423 this specifies the section containing any request attributes: its format
424 is the same as B<distinguished_name>. Typically these may contain the
425 challengePassword or unstructuredName types. They are currently ignored
426 by OpenSSL's request signing utilities but some CAs might want them.
428 =item B<distinguished_name>
430 This specifies the section containing the distinguished name fields to
431 prompt for when generating a certificate or certificate request. The format
432 is described in the next section.
436 =head1 DISTINGUISHED NAME AND ATTRIBUTE SECTION FORMAT
438 There are two separate formats for the distinguished name and attribute
439 sections. If the B<prompt> option is set to B<no> then these sections
440 just consist of field names and values: for example,
444 emailAddress=someone@somewhere.org
446 This allows external programs (e.g. GUI based) to generate a template file
447 with all the field names and values and just pass it to B<req>. An example
448 of this kind of configuration file is contained in the B<EXAMPLES> section.
450 Alternatively if the B<prompt> option is absent or not set to B<no> then the
451 file contains field prompting information. It consists of lines of the form:
454 fieldName_default="default field value"
458 "fieldName" is the field name being used, for example commonName (or CN).
459 The "prompt" string is used to ask the user to enter the relevant
460 details. If the user enters nothing then the default value is used if no
461 default value is present then the field is omitted. A field can
462 still be omitted if a default value is present if the user just
463 enters the '.' character.
465 The number of characters entered must be between the fieldName_min and
466 fieldName_max limits: there may be additional restrictions based
467 on the field being used (for example countryName can only ever be
468 two characters long and must fit in a PrintableString).
470 Some fields (such as organizationName) can be used more than once
471 in a DN. This presents a problem because configuration files will
472 not recognize the same name occurring twice. To avoid this problem
473 if the fieldName contains some characters followed by a full stop
474 they will be ignored. So for example a second organizationName can
475 be input by calling it "1.organizationName".
477 The actual permitted field names are any object identifier short or
478 long names. These are compiled into OpenSSL and include the usual
479 values such as commonName, countryName, localityName, organizationName,
480 organizationalUnitName, stateOrProvinceName. Additionally emailAddress
481 is include as well as name, surname, givenName initials and dnQualifier.
483 Additional object identifiers can be defined with the B<oid_file> or
484 B<oid_section> options in the configuration file. Any additional fields
485 will be treated as though they were a DirectoryString.
490 Examine and verify certificate request:
492 openssl req -in req.pem -text -verify -noout
494 Create a private key and then generate a certificate request from it:
496 openssl genrsa -out key.pem 2048
497 openssl req -new -key key.pem -out req.pem
499 The same but just using req:
501 openssl req -newkey rsa:2048 -keyout key.pem -out req.pem
503 Generate a self signed root certificate:
505 openssl req -x509 -newkey rsa:2048 -keyout key.pem -out req.pem
507 Example of a file pointed to by the B<oid_file> option:
509 1.2.3.4 shortName A longer Name
510 1.2.3.6 otherName Other longer Name
512 Example of a section pointed to by B<oid_section> making use of variable
516 testoid2=${testoid1}.6
518 Sample configuration file prompting for field values:
522 default_keyfile = privkey.pem
523 distinguished_name = req_distinguished_name
524 attributes = req_attributes
525 req_extensions = v3_ca
527 dirstring_type = nobmp
529 [ req_distinguished_name ]
530 countryName = Country Name (2 letter code)
531 countryName_default = AU
535 localityName = Locality Name (eg, city)
537 organizationalUnitName = Organizational Unit Name (eg, section)
539 commonName = Common Name (eg, YOUR name)
542 emailAddress = Email Address
543 emailAddress_max = 40
546 challengePassword = A challenge password
547 challengePassword_min = 4
548 challengePassword_max = 20
552 subjectKeyIdentifier=hash
553 authorityKeyIdentifier=keyid:always,issuer:always
554 basicConstraints = critical, CA:true
556 Sample configuration containing all field values:
559 RANDFILE = $ENV::HOME/.rnd
563 default_keyfile = keyfile.pem
564 distinguished_name = req_distinguished_name
565 attributes = req_attributes
567 output_password = mypass
569 [ req_distinguished_name ]
571 ST = Test State or Province
573 O = Organization Name
574 OU = Organizational Unit Name
576 emailAddress = test@email.address
579 challengePassword = A challenge password
584 The header and footer lines in the B<PEM> format are normally:
586 -----BEGIN CERTIFICATE REQUEST-----
587 -----END CERTIFICATE REQUEST-----
589 some software (some versions of Netscape certificate server) instead needs:
591 -----BEGIN NEW CERTIFICATE REQUEST-----
592 -----END NEW CERTIFICATE REQUEST-----
594 which is produced with the B<-newhdr> option but is otherwise compatible.
595 Either form is accepted transparently on input.
597 The certificate requests generated by B<Xenroll> with MSIE have extensions
598 added. It includes the B<keyUsage> extension which determines the type of
599 key (signature only or general purpose) and any additional OIDs entered
600 by the script in an extendedKeyUsage extension.
604 The following messages are frequently asked about:
606 Using configuration from /some/path/openssl.cnf
607 Unable to load config info
609 This is followed some time later by...
611 unable to find 'distinguished_name' in config
612 problems making Certificate Request
614 The first error message is the clue: it can't find the configuration
615 file! Certain operations (like examining a certificate request) don't
616 need a configuration file so its use isn't enforced. Generation of
617 certificates or requests however does need a configuration file. This
618 could be regarded as a bug.
620 Another puzzling message is this:
625 this is displayed when no attributes are present and the request includes
626 the correct empty B<SET OF> structure (the DER encoding of which is 0xa0
627 0x00). If you just see:
631 then the B<SET OF> is missing and the encoding is technically invalid (but
632 it is tolerated). See the description of the command line option B<-asn1-kludge>
633 for more information.
637 OpenSSL's handling of T61Strings (aka TeletexStrings) is broken: it effectively
638 treats them as ISO-8859-1 (Latin 1), Netscape and MSIE have similar behaviour.
639 This can cause problems if you need characters that aren't available in
640 PrintableStrings and you don't want to or can't use BMPStrings.
642 As a consequence of the T61String handling the only correct way to represent
643 accented characters in OpenSSL is to use a BMPString: unfortunately Netscape
644 currently chokes on these. If you have to use accented characters with Netscape
645 and MSIE then you currently need to use the invalid T61String form.
647 The current prompting is not very friendly. It doesn't allow you to confirm what
648 you've just entered. Other things like extensions in certificate requests are
649 statically defined in the configuration file. Some of these: like an email
650 address in subjectAltName should be input by the user.
654 L<x509(1)>, L<ca(1)>, L<genrsa(1)>,
655 L<gendsa(1)>, L<config(5)>,
660 Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved.
662 Licensed under the OpenSSL license (the "License"). You may not use
663 this file except in compliance with the License. You can obtain a copy
664 in the file LICENSE in the source distribution or at
665 L<https://www.openssl.org/source/license.html>.