1REQ(1) OpenSSL REQ(1)
2
6 req - PKCS#10 certificate request and certificate generating utility.
7
9 openssl req [-inform PEM|DER] [-outform PEM|DER] [-in filename]
10 [-passin arg] [-out filename] [-passout arg] [-text] [-pubkey] [-noout]
11 [-verify] [-modulus] [-new] [-rand file(s)] [-newkey rsa:bits] [-newkey
12 alg:file] [-nodes] [-key filename] [-keyform PEM|DER] [-keyout
13 filename] [-keygen_engine id] [-[digest]] [-config filename]
14 [-multivalue-rdn] [-x509] [-days n] [-set_serial n] [-asn1-kludge]
15 [-no-asn1-kludge] [-newhdr] [-extensions section] [-reqexts section]
16 [-utf8] [-nameopt] [-reqopt] [-subject] [-subj arg] [-batch] [-verbose]
17 [-engine id]
18
20 The req command primarily creates and processes certificate requests in
21 PKCS#10 format. It can additionally create self signed certificates for
22 use as root CAs for example.
23
25 -inform DER|PEM
26 This specifies the input format. The DER option uses an ASN1 DER
27 encoded form compatible with the PKCS#10. The PEM form is the
28 default format: it consists of the DER format base64 encoded with
29 additional header and footer lines.
30 -outform DER|PEM
32 This specifies the output format, the options have the same meaning
33 as the -inform option.
34 -in filename
36 This specifies the input filename to read a request from or
37 standard input if this option is not specified. A request is only
38 read if the creation options (-new and -newkey) are not specified.
39 -passin arg
41 the input file password source. For more information about the
42 format of arg see the PASS PHRASE ARGUMENTS section in openssl(1).
43 -out filename
45 This specifies the output filename to write to or standard output
46 by default.
47 -passout arg
49 the output file password source. For more information about the
50 format of arg see the PASS PHRASE ARGUMENTS section in openssl(1).
51 -text
53 prints out the certificate request in text form.
54 -subject
56 prints out the request subject (or certificate subject if -x509 is
57 specified)
58 -pubkey
60 outputs the public key.
61 -noout
63 this option prevents output of the encoded version of the request.
64 -modulus
66 this option prints out the value of the modulus of the public key
67 contained in the request.
68 -verify
70 verifies the signature on the request.
71 -new
73 this option generates a new certificate request. It will prompt the
74 user for the relevant field values. The actual fields prompted for
75 and their maximum and minimum sizes are specified in the
76 configuration file and any requested extensions.
77 If the -key option is not used it will generate a new RSA private
79 key using information specified in the configuration file.
80 -subj arg
82 Replaces subject field of input request with specified data and
83 outputs modified request. The arg must be formatted as
84 /type0=value0/type1=value1/type2=..., characters may be escaped by
85 \ (backslash), no spaces are skipped.
86 -rand file(s)
88 a file or files containing random data used to seed the random
89 number generator, or an EGD socket (see RAND_egd(3)). Multiple
90 files can be specified separated by a OS-dependent character. The
91 separator is ; for MS-Windows, , for OpenVMS, and : for all others.
92 -newkey arg
94 this option creates a new certificate request and a new private
95 key. The argument takes one of several forms. rsa:nbits, where
96 nbits is the number of bits, generates an RSA key nbits in size. If
97 nbits is omitted, i.e. -newkey rsa specified, the default key size,
98 specified in the configuration file is used.
99 All other algorithms support the -newkey alg:file form, where file
101 may be an algorithm parameter file, created by the genpkey
102 -genparam command or and X.509 certificate for a key with
103 approriate algorithm.
104 param:file generates a key using the parameter file or certificate
106 file, the algorithm is determined by the parameters. algname:file
107 use algorithm algname and parameter file file: the two algorithms
108 must match or an error occurs. algname just uses algorithm algname,
109 and parameters, if neccessary should be specified via -pkeyopt
110 parameter.
111 dsa:filename generates a DSA key using the parameters in the file
113 filename. ec:filename generates EC key (usable both with ECDSA or
114 ECDH algorithms), gost2001:filename generates GOST R 34.10-2001 key
115 (requires ccgost engine configured in the configuration file). If
116 just gost2001 is specified a parameter set should be specified by
117 -pkeyopt paramset:X
118 -pkeyopt opt:value
120 set the public key algorithm option opt to value. The precise set
121 of options supported depends on the public key algorithm used and
122 its implementation. See KEY GENERATION OPTIONS in the genpkey
123 manual page for more details.
124 -key filename
126 This specifies the file to read the private key from. It also
127 accepts PKCS#8 format private keys for PEM format files.
128 -keyform PEM|DER
130 the format of the private key file specified in the -key argument.
131 PEM is the default.
132 -keyout filename
134 this gives the filename to write the newly created private key to.
135 If this option is not specified then the filename present in the
136 configuration file is used.
137 -nodes
139 if this option is specified then if a private key is created it
140 will not be encrypted.
141 -[digest]
143 this specifies the message digest to sign the request with (such as
144 -md5, -sha1). This overrides the digest algorithm specified in the
145 configuration file. For full list of possible digests see openssl
146 dgst -h output.
147 Some public key algorithms may override this choice. For instance,
149 DSA signatures always use SHA1, GOST R 34.10 signatures always use
150 GOST R 34.11-94 (-md_gost94).
151 -config filename
153 this allows an alternative configuration file to be specified, this
154 overrides the compile time filename or any specified in the
155 OPENSSL_CONF environment variable.
156 -subj arg
158 sets subject name for new request or supersedes the subject name
159 when processing a request. The arg must be formatted as
160 /type0=value0/type1=value1/type2=..., characters may be escaped by
161 \ (backslash), no spaces are skipped.
162 -multivalue-rdn
164 this option causes the -subj argument to be interpreted with full
165 support for multivalued RDNs. Example:
166 /DC=org/DC=OpenSSL/DC=users/UID=123456+CN=John Doe
168 If -multi-rdn is not used then the UID value is 123456+CN=John Doe.
170 -x509
172 this option outputs a self signed certificate instead of a
173 certificate request. This is typically used to generate a test
174 certificate or a self signed root CA. The extensions added to the
175 certificate (if any) are specified in the configuration file.
176 Unless specified using the set_serial option, a large random number
177 will be used for the serial number.
178 -days n
180 when the -x509 option is being used this specifies the number of
181 days to certify the certificate for. The default is 30 days.
182 -set_serial n
184 serial number to use when outputting a self signed certificate.
185 This may be specified as a decimal value or a hex value if preceded
186 by 0x. It is possible to use negative serial numbers but this is
187 not recommended.
188 -extensions section
190 -reqexts section
191 these options specify alternative sections to include certificate
192 extensions (if the -x509 option is present) or certificate request
193 extensions. This allows several different sections to be used in
194 the same configuration file to specify requests for a variety of
195 purposes.
196 -utf8
198 this option causes field values to be interpreted as UTF8 strings,
199 by default they are interpreted as ASCII. This means that the field
200 values, whether prompted from a terminal or obtained from a
201 configuration file, must be valid UTF8 strings.
202 -nameopt option
204 option which determines how the subject or issuer names are
205 displayed. The option argument can be a single option or multiple
206 options separated by commas. Alternatively the -nameopt switch may
207 be used more than once to set multiple options. See the x509(1)
208 manual page for details.
209 -reqopt
211 customise the output format used with -text. The option argument
212 can be a single option or multiple options separated by commas.
213 See discission of the -certopt parameter in the x509 command.
215 -asn1-kludge
217 by default the req command outputs certificate requests containing
218 no attributes in the correct PKCS#10 format. However certain CAs
219 will only accept requests containing no attributes in an invalid
220 form: this option produces this invalid format.
221 More precisely the Attributes in a PKCS#10 certificate request are
223 defined as a SET OF Attribute. They are not OPTIONAL so if no
224 attributes are present then they should be encoded as an empty SET
225 OF. The invalid form does not include the empty SET OF whereas the
226 correct form does.
227 It should be noted that very few CAs still require the use of this
229 option.
230 -no-asn1-kludge
232 Reverses effect of -asn1-kludge
233 -newhdr
235 Adds the word NEW to the PEM file header and footer lines on the
236 outputted request. Some software (Netscape certificate server) and
237 some CAs need this.
238 -batch
240 non-interactive mode.
241 -verbose
243 print extra details about the operations being performed.
244 -engine id
246 specifying an engine (by its unique id string) will cause req to
247 attempt to obtain a functional reference to the specified engine,
248 thus initialising it if needed. The engine will then be set as the
249 default for all available algorithms.
250 -keygen_engine id
252 specifies an engine (by its unique id string) which would be used
253 for key generation operations.
254
256 The configuration options are specified in the req section of the
257 configuration file. As with all configuration files if no value is
258 specified in the specific section (i.e. req) then the initial unnamed
259 or default section is searched too.
260 The options available are described in detail below.
262 input_password output_password
264 The passwords for the input private key file (if present) and the
265 output private key file (if one will be created). The command line
266 options passin and passout override the configuration file values.
267 default_bits
269 Specifies the default key size in bits.
270 This option is used in conjunction with the -new option to generate
272 a new key. It can be overridden by specifying an explicit key size
273 in the -newkey option. The smallest accepted key size is 512 bits.
274 If no key size is specified then 2048 bits is used.
275 default_keyfile
277 This is the default filename to write a private key to. If not
278 specified the key is written to standard output. This can be
279 overridden by the -keyout option.
280 oid_file
282 This specifies a file containing additional OBJECT IDENTIFIERS.
283 Each line of the file should consist of the numerical form of the
284 object identifier followed by white space then the short name
285 followed by white space and finally the long name.
286 oid_section
288 This specifies a section in the configuration file containing extra
289 object identifiers. Each line should consist of the short name of
290 the object identifier followed by = and the numerical form. The
291 short and long names are the same when this option is used.
292 RANDFILE
294 This specifies a filename in which random number seed information
295 is placed and read from, or an EGD socket (see RAND_egd(3)). It is
296 used for private key generation.
297 encrypt_key
299 If this is set to no then if a private key is generated it is not
300 encrypted. This is equivalent to the -nodes command line option.
301 For compatibility encrypt_rsa_key is an equivalent option.
302 default_md
304 This option specifies the digest algorithm to use. Possible values
305 include md5 sha1 mdc2. If not present then MD5 is used. This option
306 can be overridden on the command line.
307 string_mask
309 This option masks out the use of certain string types in certain
310 fields. Most users will not need to change this option.
311 It can be set to several values default which is also the default
313 option uses PrintableStrings, T61Strings and BMPStrings if the pkix
314 value is used then only PrintableStrings and BMPStrings will be
315 used. This follows the PKIX recommendation in RFC2459. If the
316 utf8only option is used then only UTF8Strings will be used: this is
317 the PKIX recommendation in RFC2459 after 2003. Finally the nombstr
318 option just uses PrintableStrings and T61Strings: certain software
319 has problems with BMPStrings and UTF8Strings: in particular
320 Netscape.
321 req_extensions
323 this specifies the configuration file section containing a list of
324 extensions to add to the certificate request. It can be overridden
325 by the -reqexts command line switch. See the x509v3_config(5)
326 manual page for details of the extension section format.
327 x509_extensions
329 this specifies the configuration file section containing a list of
330 extensions to add to certificate generated when the -x509 switch is
331 used. It can be overridden by the -extensions command line switch.
332 prompt
334 if set to the value no this disables prompting of certificate
335 fields and just takes values from the config file directly. It also
336 changes the expected format of the distinguished_name and
337 attributes sections.
338 utf8
340 if set to the value yes then field values to be interpreted as UTF8
341 strings, by default they are interpreted as ASCII. This means that
342 the field values, whether prompted from a terminal or obtained from
343 a configuration file, must be valid UTF8 strings.
344 attributes
346 this specifies the section containing any request attributes: its
347 format is the same as distinguished_name. Typically these may
348 contain the challengePassword or unstructuredName types. They are
349 currently ignored by OpenSSL's request signing utilities but some
350 CAs might want them.
351 distinguished_name
353 This specifies the section containing the distinguished name fields
354 to prompt for when generating a certificate or certificate request.
355 The format is described in the next section.
356
358 There are two separate formats for the distinguished name and attribute
359 sections. If the prompt option is set to no then these sections just
360 consist of field names and values: for example,
361 CN=My Name
363 OU=My Organization
364 emailAddress=someone@somewhere.org
365 This allows external programs (e.g. GUI based) to generate a template
367 file with all the field names and values and just pass it to req. An
368 example of this kind of configuration file is contained in the EXAMPLES
369 section.
370 Alternatively if the prompt option is absent or not set to no then the
372 file contains field prompting information. It consists of lines of the
373 form:
374 fieldName="prompt"
376 fieldName_default="default field value"
377 fieldName_min= 2
378 fieldName_max= 4
379 "fieldName" is the field name being used, for example commonName (or
381 CN). The "prompt" string is used to ask the user to enter the relevant
382 details. If the user enters nothing then the default value is used if
383 no default value is present then the field is omitted. A field can
384 still be omitted if a default value is present if the user just enters
385 the '.' character.
386 The number of characters entered must be between the fieldName_min and
388 fieldName_max limits: there may be additional restrictions based on the
389 field being used (for example countryName can only ever be two
390 characters long and must fit in a PrintableString).
391 Some fields (such as organizationName) can be used more than once in a
393 DN. This presents a problem because configuration files will not
394 recognize the same name occurring twice. To avoid this problem if the
395 fieldName contains some characters followed by a full stop they will be
396 ignored. So for example a second organizationName can be input by
397 calling it "1.organizationName".
398 The actual permitted field names are any object identifier short or
400 long names. These are compiled into OpenSSL and include the usual
401 values such as commonName, countryName, localityName, organizationName,
402 organizationalUnitName, stateOrProvinceName. Additionally emailAddress
403 is include as well as name, surname, givenName initials and
404 dnQualifier.
405 Additional object identifiers can be defined with the oid_file or
407 oid_section options in the configuration file. Any additional fields
408 will be treated as though they were a DirectoryString.
409
411 Examine and verify certificate request:
412 openssl req -in req.pem -text -verify -noout
414 Create a private key and then generate a certificate request from it:
416 openssl genrsa -out key.pem 2048
418 openssl req -new -key key.pem -out req.pem
419 The same but just using req:
421 openssl req -newkey rsa:2048 -keyout key.pem -out req.pem
423 Generate a self signed root certificate:
425 openssl req -x509 -newkey rsa:2048 -keyout key.pem -out req.pem
427 Example of a file pointed to by the oid_file option:
429 1.2.3.4 shortName A longer Name
431 1.2.3.6 otherName Other longer Name
432 Example of a section pointed to by oid_section making use of variable
434 expansion:
435 testoid1=1.2.3.5
437 testoid2=${testoid1}.6
438 Sample configuration file prompting for field values:
440 [ req ]
442 default_bits = 2048
443 default_keyfile = privkey.pem
444 distinguished_name = req_distinguished_name
445 attributes = req_attributes
446 x509_extensions = v3_ca
447 dirstring_type = nobmp
449 [ req_distinguished_name ]
451 countryName = Country Name (2 letter code)
452 countryName_default = AU
453 countryName_min = 2
454 countryName_max = 2
455 localityName = Locality Name (eg, city)
457 organizationalUnitName = Organizational Unit Name (eg, section)
459 commonName = Common Name (eg, YOUR name)
461 commonName_max = 64
462 emailAddress = Email Address
464 emailAddress_max = 40
465 [ req_attributes ]
467 challengePassword = A challenge password
468 challengePassword_min = 4
469 challengePassword_max = 20
470 [ v3_ca ]
472 subjectKeyIdentifier=hash
474 authorityKeyIdentifier=keyid:always,issuer:always
475 basicConstraints = CA:true
476 Sample configuration containing all field values:
478 RANDFILE = $ENV::HOME/.rnd
480 [ req ]
482 default_bits = 2048
483 default_keyfile = keyfile.pem
484 distinguished_name = req_distinguished_name
485 attributes = req_attributes
486 prompt = no
487 output_password = mypass
488 [ req_distinguished_name ]
490 C = GB
491 ST = Test State or Province
492 L = Test Locality
493 O = Organization Name
494 OU = Organizational Unit Name
495 CN = Common Name
496 emailAddress = test@email.address
497 [ req_attributes ]
499 challengePassword = A challenge password
500
502 The header and footer lines in the PEM format are normally:
503 -----BEGIN CERTIFICATE REQUEST-----
505 -----END CERTIFICATE REQUEST-----
506 some software (some versions of Netscape certificate server) instead
508 needs:
509 -----BEGIN NEW CERTIFICATE REQUEST-----
511 -----END NEW CERTIFICATE REQUEST-----
512 which is produced with the -newhdr option but is otherwise compatible.
514 Either form is accepted transparently on input.
515 The certificate requests generated by Xenroll with MSIE have extensions
517 added. It includes the keyUsage extension which determines the type of
518 key (signature only or general purpose) and any additional OIDs entered
519 by the script in an extendedKeyUsage extension.
520
522 The following messages are frequently asked about:
523 Using configuration from /some/path/openssl.cnf
525 Unable to load config info
526 This is followed some time later by...
528 unable to find 'distinguished_name' in config
530 problems making Certificate Request
531 The first error message is the clue: it can't find the configuration
533 file! Certain operations (like examining a certificate request) don't
534 need a configuration file so its use isn't enforced. Generation of
535 certificates or requests however does need a configuration file. This
536 could be regarded as a bug.
537 Another puzzling message is this:
539 Attributes:
541 a0:00
542 this is displayed when no attributes are present and the request
544 includes the correct empty SET OF structure (the DER encoding of which
545 is 0xa0 0x00). If you just see:
546 Attributes:
548 then the SET OF is missing and the encoding is technically invalid (but
550 it is tolerated). See the description of the command line option
551 -asn1-kludge for more information.
552
554 The variable OPENSSL_CONF if defined allows an alternative
555 configuration file location to be specified, it will be overridden by
556 the -config command line switch if it is present. For compatibility
557 reasons the SSLEAY_CONF environment variable serves the same purpose
558 but its use is discouraged.
559
561 OpenSSL's handling of T61Strings (aka TeletexStrings) is broken: it
562 effectively treats them as ISO-8859-1 (Latin 1), Netscape and MSIE have
563 similar behaviour. This can cause problems if you need characters that
564 aren't available in PrintableStrings and you don't want to or can't use
565 BMPStrings.
566 As a consequence of the T61String handling the only correct way to
568 represent accented characters in OpenSSL is to use a BMPString:
569 unfortunately Netscape currently chokes on these. If you have to use
570 accented characters with Netscape and MSIE then you currently need to
571 use the invalid T61String form.
572 The current prompting is not very friendly. It doesn't allow you to
574 confirm what you've just entered. Other things like extensions in
575 certificate requests are statically defined in the configuration file.
576 Some of these: like an email address in subjectAltName should be input
577 by the user.
578
580 x509(1), ca(1), genrsa(1), gendsa(1), config(5), x509v3_config(5)
5811.0.2k 2019-03-12 REQ(1)