6 req - PKCS#10 certificate request and certificate generating utility.
31 [B<-keygen_engine id>]
39 [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.
56 =head1 COMMAND OPTIONS
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 this overrides the compile time filename or any specified in
210 the B<OPENSSL_CONF> environment variable.
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>.
246 It is possible to use negative serial numbers but this is not recommended.
248 =item B<-extensions section>
250 =item B<-reqexts section>
252 these options specify alternative sections to include certificate
253 extensions (if the B<-x509> option is present) or certificate
254 request extensions. This allows several different sections to
255 be used in the same configuration file to specify requests for
256 a variety of purposes.
260 this option causes field values to be interpreted as UTF8 strings, by
261 default they are interpreted as ASCII. This means that the field
262 values, whether prompted from a terminal or obtained from a
263 configuration file, must be valid UTF8 strings.
265 =item B<-nameopt option>
267 option which determines how the subject or issuer names are displayed. The
268 B<option> argument can be a single option or multiple options separated by
269 commas. Alternatively the B<-nameopt> switch may be used more than once to
270 set multiple options. See the L<x509(1)> manual page for details.
274 customise the output format used with B<-text>. The B<option> argument can be
275 a single option or multiple options separated by commas.
277 See discussion of the B<-certopt> parameter in the L<x509(1)>
282 Adds the word B<NEW> to the PEM file header and footer lines on the outputted
283 request. Some software (Netscape certificate server) and some CAs need this.
287 non-interactive mode.
291 print extra details about the operations being performed.
295 specifying an engine (by its unique B<id> string) will cause B<req>
296 to attempt to obtain a functional reference to the specified engine,
297 thus initialising it if needed. The engine will then be set as the default
298 for all available algorithms.
300 =item B<-keygen_engine id>
302 specifies an engine (by its unique B<id> string) which would be used
303 for key generation operations.
307 =head1 CONFIGURATION FILE FORMAT
309 The configuration options are specified in the B<req> section of
310 the configuration file. As with all configuration files if no
311 value is specified in the specific section (i.e. B<req>) then
312 the initial unnamed or B<default> section is searched too.
314 The options available are described in detail below.
318 =item B<input_password output_password>
320 The passwords for the input private key file (if present) and
321 the output private key file (if one will be created). The
322 command line options B<passin> and B<passout> override the
323 configuration file values.
325 =item B<default_bits>
327 Specifies the default key size in bits.
329 This option is used in conjunction with the B<-new> option to generate
330 a new key. It can be overridden by specifying an explicit key size in
331 the B<-newkey> option. The smallest accepted key size is 512 bits. If
332 no key size is specified then 2048 bits is used.
334 =item B<default_keyfile>
336 This is the default filename to write a private key to. If not
337 specified the key is written to standard output. This can be
338 overridden by the B<-keyout> option.
342 This specifies a file containing additional B<OBJECT IDENTIFIERS>.
343 Each line of the file should consist of the numerical form of the
344 object identifier followed by white space then the short name followed
345 by white space and finally the long name.
349 This specifies a section in the configuration file containing extra
350 object identifiers. Each line should consist of the short name of the
351 object identifier followed by B<=> and the numerical form. The short
352 and long names are the same when this option is used.
356 This specifies a filename in which random number seed information is
357 placed and read from, or an EGD socket (see L<RAND_egd(3)>).
358 It is used for private key generation.
362 If this is set to B<no> then if a private key is generated it is
363 B<not> encrypted. This is equivalent to the B<-nodes> command line
364 option. For compatibility B<encrypt_rsa_key> is an equivalent option.
368 This option specifies the digest algorithm to use.
369 Any digest supported by the OpenSSL B<dgst> command can be used.
370 If not present then MD5 is used.
371 This option can be overridden on the command line.
375 This option masks out the use of certain string types in certain
376 fields. Most users will not need to change this option.
378 It can be set to several values B<default> which is also the default
379 option uses PrintableStrings, T61Strings and BMPStrings if the
380 B<pkix> value is used then only PrintableStrings and BMPStrings will
381 be used. This follows the PKIX recommendation in RFC2459. If the
382 B<utf8only> option is used then only UTF8Strings will be used: this
383 is the PKIX recommendation in RFC2459 after 2003. Finally the B<nombstr>
384 option just uses PrintableStrings and T61Strings: certain software has
385 problems with BMPStrings and UTF8Strings: in particular Netscape.
387 =item B<req_extensions>
389 this specifies the configuration file section containing a list of
390 extensions to add to the certificate request. It can be overridden
391 by the B<-reqexts> command line switch. See the
392 L<x509v3_config(5)> manual page for details of the
393 extension section format.
395 =item B<x509_extensions>
397 this specifies the configuration file section containing a list of
398 extensions to add to certificate generated when the B<-x509> switch
399 is used. It can be overridden by the B<-extensions> command line switch.
403 if set to the value B<no> this disables prompting of certificate fields
404 and just takes values from the config file directly. It also changes the
405 expected format of the B<distinguished_name> and B<attributes> sections.
409 if set to the value B<yes> then field values to be interpreted as UTF8
410 strings, by default they are interpreted as ASCII. This means that
411 the field values, whether prompted from a terminal or obtained from a
412 configuration file, must be valid UTF8 strings.
416 this specifies the section containing any request attributes: its format
417 is the same as B<distinguished_name>. Typically these may contain the
418 challengePassword or unstructuredName types. They are currently ignored
419 by OpenSSL's request signing utilities but some CAs might want them.
421 =item B<distinguished_name>
423 This specifies the section containing the distinguished name fields to
424 prompt for when generating a certificate or certificate request. The format
425 is described in the next section.
429 =head1 DISTINGUISHED NAME AND ATTRIBUTE SECTION FORMAT
431 There are two separate formats for the distinguished name and attribute
432 sections. If the B<prompt> option is set to B<no> then these sections
433 just consist of field names and values: for example,
437 emailAddress=someone@somewhere.org
439 This allows external programs (e.g. GUI based) to generate a template file
440 with all the field names and values and just pass it to B<req>. An example
441 of this kind of configuration file is contained in the B<EXAMPLES> section.
443 Alternatively if the B<prompt> option is absent or not set to B<no> then the
444 file contains field prompting information. It consists of lines of the form:
447 fieldName_default="default field value"
451 "fieldName" is the field name being used, for example commonName (or CN).
452 The "prompt" string is used to ask the user to enter the relevant
453 details. If the user enters nothing then the default value is used if no
454 default value is present then the field is omitted. A field can
455 still be omitted if a default value is present if the user just
456 enters the '.' character.
458 The number of characters entered must be between the fieldName_min and
459 fieldName_max limits: there may be additional restrictions based
460 on the field being used (for example countryName can only ever be
461 two characters long and must fit in a PrintableString).
463 Some fields (such as organizationName) can be used more than once
464 in a DN. This presents a problem because configuration files will
465 not recognize the same name occurring twice. To avoid this problem
466 if the fieldName contains some characters followed by a full stop
467 they will be ignored. So for example a second organizationName can
468 be input by calling it "1.organizationName".
470 The actual permitted field names are any object identifier short or
471 long names. These are compiled into OpenSSL and include the usual
472 values such as commonName, countryName, localityName, organizationName,
473 organizationalUnitName, stateOrProvinceName. Additionally emailAddress
474 is include as well as name, surname, givenName initials and dnQualifier.
476 Additional object identifiers can be defined with the B<oid_file> or
477 B<oid_section> options in the configuration file. Any additional fields
478 will be treated as though they were a DirectoryString.
483 Examine and verify certificate request:
485 openssl req -in req.pem -text -verify -noout
487 Create a private key and then generate a certificate request from it:
489 openssl genrsa -out key.pem 2048
490 openssl req -new -key key.pem -out req.pem
492 The same but just using req:
494 openssl req -newkey rsa:2048 -keyout key.pem -out req.pem
496 Generate a self signed root certificate:
498 openssl req -x509 -newkey rsa:2048 -keyout key.pem -out req.pem
500 Example of a file pointed to by the B<oid_file> option:
502 1.2.3.4 shortName A longer Name
503 1.2.3.6 otherName Other longer Name
505 Example of a section pointed to by B<oid_section> making use of variable
509 testoid2=${testoid1}.6
511 Sample configuration file prompting for field values:
515 default_keyfile = privkey.pem
516 distinguished_name = req_distinguished_name
517 attributes = req_attributes
518 req_extensions = v3_ca
520 dirstring_type = nobmp
522 [ req_distinguished_name ]
523 countryName = Country Name (2 letter code)
524 countryName_default = AU
528 localityName = Locality Name (eg, city)
530 organizationalUnitName = Organizational Unit Name (eg, section)
532 commonName = Common Name (eg, YOUR name)
535 emailAddress = Email Address
536 emailAddress_max = 40
539 challengePassword = A challenge password
540 challengePassword_min = 4
541 challengePassword_max = 20
545 subjectKeyIdentifier=hash
546 authorityKeyIdentifier=keyid:always,issuer:always
547 basicConstraints = CA:true
549 Sample configuration containing all field values:
552 RANDFILE = $ENV::HOME/.rnd
556 default_keyfile = keyfile.pem
557 distinguished_name = req_distinguished_name
558 attributes = req_attributes
560 output_password = mypass
562 [ req_distinguished_name ]
564 ST = Test State or Province
566 O = Organization Name
567 OU = Organizational Unit Name
569 emailAddress = test@email.address
572 challengePassword = A challenge password
577 The header and footer lines in the B<PEM> format are normally:
579 -----BEGIN CERTIFICATE REQUEST-----
580 -----END CERTIFICATE REQUEST-----
582 some software (some versions of Netscape certificate server) instead needs:
584 -----BEGIN NEW CERTIFICATE REQUEST-----
585 -----END NEW CERTIFICATE REQUEST-----
587 which is produced with the B<-newhdr> option but is otherwise compatible.
588 Either form is accepted transparently on input.
590 The certificate requests generated by B<Xenroll> with MSIE have extensions
591 added. It includes the B<keyUsage> extension which determines the type of
592 key (signature only or general purpose) and any additional OIDs entered
593 by the script in an extendedKeyUsage extension.
597 The following messages are frequently asked about:
599 Using configuration from /some/path/openssl.cnf
600 Unable to load config info
602 This is followed some time later by...
604 unable to find 'distinguished_name' in config
605 problems making Certificate Request
607 The first error message is the clue: it can't find the configuration
608 file! Certain operations (like examining a certificate request) don't
609 need a configuration file so its use isn't enforced. Generation of
610 certificates or requests however does need a configuration file. This
611 could be regarded as a bug.
613 Another puzzling message is this:
618 this is displayed when no attributes are present and the request includes
619 the correct empty B<SET OF> structure (the DER encoding of which is 0xa0
620 0x00). If you just see:
624 then the B<SET OF> is missing and the encoding is technically invalid (but
625 it is tolerated). See the description of the command line option B<-asn1-kludge>
626 for more information.
628 =head1 ENVIRONMENT VARIABLES
630 The variable B<OPENSSL_CONF> if defined allows an alternative configuration
631 file location to be specified, it will be overridden by the B<-config> command
632 line switch if it is present.
636 OpenSSL's handling of T61Strings (aka TeletexStrings) is broken: it effectively
637 treats them as ISO-8859-1 (Latin 1), Netscape and MSIE have similar behaviour.
638 This can cause problems if you need characters that aren't available in
639 PrintableStrings and you don't want to or can't use BMPStrings.
641 As a consequence of the T61String handling the only correct way to represent
642 accented characters in OpenSSL is to use a BMPString: unfortunately Netscape
643 currently chokes on these. If you have to use accented characters with Netscape
644 and MSIE then you currently need to use the invalid T61String form.
646 The current prompting is not very friendly. It doesn't allow you to confirm what
647 you've just entered. Other things like extensions in certificate requests are
648 statically defined in the configuration file. Some of these: like an email
649 address in subjectAltName should be input by the user.
653 L<x509(1)>, L<ca(1)>, L<genrsa(1)>,
654 L<gendsa(1)>, L<config(5)>,