5 req - PKCS#10 certificate request and certificate generating utility
30 [B<-keygen_engine id>]
38 [B<-extensions section>]
51 The B<req> command primarily creates and processes certificate requests
52 in PKCS#10 format. It can additionally create self signed certificates
53 for use as root CAs for example.
55 =head1 COMMAND OPTIONS
61 Print out a usage message.
63 =item B<-inform DER|PEM>
65 This specifies the input format. The B<DER> option uses an ASN1 DER encoded
66 form compatible with the PKCS#10. The B<PEM> form is the default format: it
67 consists of the B<DER> format base64 encoded with additional header and
70 =item B<-outform DER|PEM>
72 This specifies the output format, the options have the same meaning as the
77 This specifies the input filename to read a request from or standard input
78 if this option is not specified. A request is only read if the creation
79 options (B<-new> and B<-newkey>) are not specified.
83 the input file password source. For more information about the format of B<arg>
84 see the B<PASS PHRASE ARGUMENTS> section in L<openssl(1)>.
86 =item B<-out filename>
88 This specifies the output filename to write to or standard output by
93 the output file password source. For more information about the format of B<arg>
94 see the B<PASS PHRASE ARGUMENTS> section in L<openssl(1)>.
98 prints out the certificate request in text form.
102 prints out the request subject (or certificate subject if B<-x509> is
107 outputs the public key.
111 this option prevents output of the encoded version of the request.
115 this option prints out the value of the modulus of the public key
116 contained in the request.
120 verifies the signature on the request.
124 this option generates a new certificate request. It will prompt
125 the user for the relevant field values. The actual fields
126 prompted for and their maximum and minimum sizes are specified
127 in the configuration file and any requested extensions.
129 If the B<-key> option is not used it will generate a new RSA private
130 key using information specified in the configuration file.
132 =item B<-rand file(s)>
134 a file or files containing random data used to seed the random number
135 generator, or an EGD socket (see L<RAND_egd(3)>).
136 Multiple files can be specified separated by an OS-dependent character.
137 The separator is B<;> for MS-Windows, B<,> for OpenVMS, and B<:> for
142 this option creates a new certificate request and a new private
143 key. The argument takes one of several forms. B<rsa:nbits>, where
144 B<nbits> is the number of bits, generates an RSA key B<nbits>
145 in size. If B<nbits> is omitted, i.e. B<-newkey rsa> specified,
146 the default key size, specified in the configuration file is used.
148 All other algorithms support the B<-newkey alg:file> form, where file may be
149 an algorithm parameter file, created by the B<genpkey -genparam> command
150 or and X.509 certificate for a key with appropriate algorithm.
152 B<param:file> generates a key using the parameter file or certificate B<file>,
153 the algorithm is determined by the parameters. B<algname:file> use algorithm
154 B<algname> and parameter file B<file>: the two algorithms must match or an
155 error occurs. B<algname> just uses algorithm B<algname>, and parameters,
156 if necessary should be specified via B<-pkeyopt> parameter.
158 B<dsa:filename> generates a DSA key using the parameters
159 in the file B<filename>. B<ec:filename> generates EC key (usable both with
160 ECDSA or ECDH algorithms), B<gost2001:filename> generates GOST R
161 34.10-2001 key (requires B<ccgost> engine configured in the configuration
162 file). If just B<gost2001> is specified a parameter set should be
163 specified by B<-pkeyopt paramset:X>
166 =item B<-pkeyopt opt:value>
168 set the public key algorithm option B<opt> to B<value>. The precise set of
169 options supported depends on the public key algorithm used and its
170 implementation. See B<KEY GENERATION OPTIONS> in the B<genpkey> manual page
173 =item B<-key filename>
175 This specifies the file to read the private key from. It also
176 accepts PKCS#8 format private keys for PEM format files.
178 =item B<-keyform PEM|DER>
180 the format of the private key file specified in the B<-key>
181 argument. PEM is the default.
183 =item B<-keyout filename>
185 this gives the filename to write the newly created private key to.
186 If this option is not specified then the filename present in the
187 configuration file is used.
191 if this option is specified then if a private key is created it
192 will not be encrypted.
196 this specifies the message digest to sign the request.
197 Any digest supported by the OpenSSL B<dgst> command can be used.
198 This overrides the digest algorithm specified in
199 the configuration file.
201 Some public key algorithms may override this choice. For instance, DSA
202 signatures always use SHA1, GOST R 34.10 signatures always use
203 GOST R 34.11-94 (B<-md_gost94>).
205 =item B<-config filename>
207 this allows an alternative configuration file to be specified,
208 this overrides the compile time filename or any specified in
209 the B<OPENSSL_CONF> environment variable.
213 sets subject name for new request or supersedes the subject name
214 when processing a request.
215 The arg must be formatted as I</type0=value0/type1=value1/type2=...>,
216 characters may be escaped by \ (backslash), no spaces are skipped.
218 =item B<-multivalue-rdn>
220 this option causes the -subj argument to be interpreted with full
221 support for multivalued RDNs. Example:
223 I</DC=org/DC=OpenSSL/DC=users/UID=123456+CN=John Doe>
225 If -multi-rdn is not used then the UID value is I<123456+CN=John Doe>.
229 this option outputs a self signed certificate instead of a certificate
230 request. This is typically used to generate a test certificate or
231 a self signed root CA. The extensions added to the certificate
232 (if any) are specified in the configuration file. Unless specified
233 using the B<set_serial> option, a large random number will be used for
238 when the B<-x509> option is being used this specifies the number of
239 days to certify the certificate for. The default is 30 days.
241 =item B<-set_serial n>
243 serial number to use when outputting a self signed certificate. This
244 may be specified as a decimal value or a hex value if preceded by B<0x>.
245 It is possible to use negative serial numbers but this is not recommended.
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 this option causes field values to be interpreted as UTF8 strings, by
260 default they are interpreted as ASCII. This means that the field
261 values, whether prompted from a terminal or obtained from a
262 configuration file, must be valid UTF8 strings.
264 =item B<-nameopt option>
266 option which determines how the subject or issuer names are displayed. The
267 B<option> argument can be a single option or multiple options separated by
268 commas. Alternatively the B<-nameopt> switch may be used more than once to
269 set multiple options. See the L<x509(1)> manual page for details.
273 customise the output format used with B<-text>. The B<option> argument can be
274 a single option or multiple options separated by commas.
276 See discussion of the B<-certopt> parameter in the L<x509(1)>
281 Adds the word B<NEW> to the PEM file header and footer lines on the outputted
282 request. Some software (Netscape certificate server) and some CAs need this.
286 non-interactive mode.
290 print extra details about the operations being performed.
294 specifying an engine (by its unique B<id> string) will cause B<req>
295 to attempt to obtain a functional reference to the specified engine,
296 thus initialising it if needed. The engine will then be set as the default
297 for all available algorithms.
299 =item B<-keygen_engine id>
301 specifies an engine (by its unique B<id> string) which would be used
302 for key generation operations.
306 =head1 CONFIGURATION FILE FORMAT
308 The configuration options are specified in the B<req> section of
309 the configuration file. As with all configuration files if no
310 value is specified in the specific section (i.e. B<req>) then
311 the initial unnamed or B<default> section is searched too.
313 The options available are described in detail below.
317 =item B<input_password output_password>
319 The passwords for the input private key file (if present) and
320 the output private key file (if one will be created). The
321 command line options B<passin> and B<passout> override the
322 configuration file values.
324 =item B<default_bits>
326 Specifies the default key size in bits.
328 This option is used in conjunction with the B<-new> option to generate
329 a new key. It can be overridden by specifying an explicit key size in
330 the B<-newkey> option. The smallest accepted key size is 512 bits. If
331 no key size is specified then 2048 bits is used.
333 =item B<default_keyfile>
335 This is the default filename to write a private key to. If not
336 specified the key is written to standard output. This can be
337 overridden by the B<-keyout> option.
341 This specifies a file containing additional B<OBJECT IDENTIFIERS>.
342 Each line of the file should consist of the numerical form of the
343 object identifier followed by white space then the short name followed
344 by white space and finally the long name.
348 This specifies a section in the configuration file containing extra
349 object identifiers. Each line should consist of the short name of the
350 object identifier followed by B<=> and the numerical form. The short
351 and long names are the same when this option is used.
355 This specifies a filename in which random number seed information is
356 placed and read from, or an EGD socket (see L<RAND_egd(3)>).
357 It is used for private key generation.
361 If this is set to B<no> then if a private key is generated it is
362 B<not> encrypted. This is equivalent to the B<-nodes> command line
363 option. For compatibility B<encrypt_rsa_key> is an equivalent option.
367 This option specifies the digest algorithm to use.
368 Any digest supported by the OpenSSL B<dgst> command can be used.
369 If not present then MD5 is used.
370 This option can be overridden on the command line.
374 This option masks out the use of certain string types in certain
375 fields. Most users will not need to change this option.
377 It can be set to several values B<default> which is also the default
378 option uses PrintableStrings, T61Strings and BMPStrings if the
379 B<pkix> value is used then only PrintableStrings and BMPStrings will
380 be used. This follows the PKIX recommendation in RFC2459. If the
381 B<utf8only> option is used then only UTF8Strings will be used: this
382 is the PKIX recommendation in RFC2459 after 2003. Finally the B<nombstr>
383 option just uses PrintableStrings and T61Strings: certain software has
384 problems with BMPStrings and UTF8Strings: in particular Netscape.
386 =item B<req_extensions>
388 this specifies the configuration file section containing a list of
389 extensions to add to the certificate request. It can be overridden
390 by the B<-reqexts> command line switch. See the
391 L<x509v3_config(5)> manual page for details of the
392 extension section format.
394 =item B<x509_extensions>
396 this specifies the configuration file section containing a list of
397 extensions to add to certificate generated when the B<-x509> switch
398 is used. It can be overridden by the B<-extensions> command line switch.
402 if set to the value B<no> this disables prompting of certificate fields
403 and just takes values from the config file directly. It also changes the
404 expected format of the B<distinguished_name> and B<attributes> sections.
408 if set to the value B<yes> then field values to be interpreted as UTF8
409 strings, by default they are interpreted as ASCII. This means that
410 the field values, whether prompted from a terminal or obtained from a
411 configuration file, must be valid UTF8 strings.
415 this specifies the section containing any request attributes: its format
416 is the same as B<distinguished_name>. Typically these may contain the
417 challengePassword or unstructuredName types. They are currently ignored
418 by OpenSSL's request signing utilities but some CAs might want them.
420 =item B<distinguished_name>
422 This specifies the section containing the distinguished name fields to
423 prompt for when generating a certificate or certificate request. The format
424 is described in the next section.
428 =head1 DISTINGUISHED NAME AND ATTRIBUTE SECTION FORMAT
430 There are two separate formats for the distinguished name and attribute
431 sections. If the B<prompt> option is set to B<no> then these sections
432 just consist of field names and values: for example,
436 emailAddress=someone@somewhere.org
438 This allows external programs (e.g. GUI based) to generate a template file
439 with all the field names and values and just pass it to B<req>. An example
440 of this kind of configuration file is contained in the B<EXAMPLES> section.
442 Alternatively if the B<prompt> option is absent or not set to B<no> then the
443 file contains field prompting information. It consists of lines of the form:
446 fieldName_default="default field value"
450 "fieldName" is the field name being used, for example commonName (or CN).
451 The "prompt" string is used to ask the user to enter the relevant
452 details. If the user enters nothing then the default value is used if no
453 default value is present then the field is omitted. A field can
454 still be omitted if a default value is present if the user just
455 enters the '.' character.
457 The number of characters entered must be between the fieldName_min and
458 fieldName_max limits: there may be additional restrictions based
459 on the field being used (for example countryName can only ever be
460 two characters long and must fit in a PrintableString).
462 Some fields (such as organizationName) can be used more than once
463 in a DN. This presents a problem because configuration files will
464 not recognize the same name occurring twice. To avoid this problem
465 if the fieldName contains some characters followed by a full stop
466 they will be ignored. So for example a second organizationName can
467 be input by calling it "1.organizationName".
469 The actual permitted field names are any object identifier short or
470 long names. These are compiled into OpenSSL and include the usual
471 values such as commonName, countryName, localityName, organizationName,
472 organizationalUnitName, stateOrProvinceName. Additionally emailAddress
473 is include as well as name, surname, givenName initials and dnQualifier.
475 Additional object identifiers can be defined with the B<oid_file> or
476 B<oid_section> options in the configuration file. Any additional fields
477 will be treated as though they were a DirectoryString.
482 Examine and verify certificate request:
484 openssl req -in req.pem -text -verify -noout
486 Create a private key and then generate a certificate request from it:
488 openssl genrsa -out key.pem 2048
489 openssl req -new -key key.pem -out req.pem
491 The same but just using req:
493 openssl req -newkey rsa:2048 -keyout key.pem -out req.pem
495 Generate a self signed root certificate:
497 openssl req -x509 -newkey rsa:2048 -keyout key.pem -out req.pem
499 Example of a file pointed to by the B<oid_file> option:
501 1.2.3.4 shortName A longer Name
502 1.2.3.6 otherName Other longer Name
504 Example of a section pointed to by B<oid_section> making use of variable
508 testoid2=${testoid1}.6
510 Sample configuration file prompting for field values:
514 default_keyfile = privkey.pem
515 distinguished_name = req_distinguished_name
516 attributes = req_attributes
517 req_extensions = v3_ca
519 dirstring_type = nobmp
521 [ req_distinguished_name ]
522 countryName = Country Name (2 letter code)
523 countryName_default = AU
527 localityName = Locality Name (eg, city)
529 organizationalUnitName = Organizational Unit Name (eg, section)
531 commonName = Common Name (eg, YOUR name)
534 emailAddress = Email Address
535 emailAddress_max = 40
538 challengePassword = A challenge password
539 challengePassword_min = 4
540 challengePassword_max = 20
544 subjectKeyIdentifier=hash
545 authorityKeyIdentifier=keyid:always,issuer:always
546 basicConstraints = critical, CA:true
548 Sample configuration containing all field values:
551 RANDFILE = $ENV::HOME/.rnd
555 default_keyfile = keyfile.pem
556 distinguished_name = req_distinguished_name
557 attributes = req_attributes
559 output_password = mypass
561 [ req_distinguished_name ]
563 ST = Test State or Province
565 O = Organization Name
566 OU = Organizational Unit Name
568 emailAddress = test@email.address
571 challengePassword = A challenge password
576 The header and footer lines in the B<PEM> format are normally:
578 -----BEGIN CERTIFICATE REQUEST-----
579 -----END CERTIFICATE REQUEST-----
581 some software (some versions of Netscape certificate server) instead needs:
583 -----BEGIN NEW CERTIFICATE REQUEST-----
584 -----END NEW CERTIFICATE REQUEST-----
586 which is produced with the B<-newhdr> option but is otherwise compatible.
587 Either form is accepted transparently on input.
589 The certificate requests generated by B<Xenroll> with MSIE have extensions
590 added. It includes the B<keyUsage> extension which determines the type of
591 key (signature only or general purpose) and any additional OIDs entered
592 by the script in an extendedKeyUsage extension.
596 The following messages are frequently asked about:
598 Using configuration from /some/path/openssl.cnf
599 Unable to load config info
601 This is followed some time later by...
603 unable to find 'distinguished_name' in config
604 problems making Certificate Request
606 The first error message is the clue: it can't find the configuration
607 file! Certain operations (like examining a certificate request) don't
608 need a configuration file so its use isn't enforced. Generation of
609 certificates or requests however does need a configuration file. This
610 could be regarded as a bug.
612 Another puzzling message is this:
617 this is displayed when no attributes are present and the request includes
618 the correct empty B<SET OF> structure (the DER encoding of which is 0xa0
619 0x00). If you just see:
623 then the B<SET OF> is missing and the encoding is technically invalid (but
624 it is tolerated). See the description of the command line option B<-asn1-kludge>
625 for more information.
627 =head1 ENVIRONMENT VARIABLES
629 The variable B<OPENSSL_CONF> if defined allows an alternative configuration
630 file location to be specified, it will be overridden by the B<-config> command
631 line switch if it is present.
635 OpenSSL's handling of T61Strings (aka TeletexStrings) is broken: it effectively
636 treats them as ISO-8859-1 (Latin 1), Netscape and MSIE have similar behaviour.
637 This can cause problems if you need characters that aren't available in
638 PrintableStrings and you don't want to or can't use BMPStrings.
640 As a consequence of the T61String handling the only correct way to represent
641 accented characters in OpenSSL is to use a BMPString: unfortunately Netscape
642 currently chokes on these. If you have to use accented characters with Netscape
643 and MSIE then you currently need to use the invalid T61String form.
645 The current prompting is not very friendly. It doesn't allow you to confirm what
646 you've just entered. Other things like extensions in certificate requests are
647 statically defined in the configuration file. Some of these: like an email
648 address in subjectAltName should be input by the user.
652 L<x509(1)>, L<ca(1)>, L<genrsa(1)>,
653 L<gendsa(1)>, L<config(5)>,
658 Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved.
660 Licensed under the OpenSSL license (the "License"). You may not use
661 this file except in compliance with the License. You can obtain a copy
662 in the file LICENSE in the source distribution or at
663 L<https://www.openssl.org/source/license.html>.