6 req - PKCS#10 certificate request and certificate generating utility.
30 [B<-keygen_engine id>]
40 [B<-extensions section>]
53 The B<req> command primarily creates and processes certificate requests
54 in PKCS#10 format. It can additionally create self signed certificates
55 for use as root CAs for example.
57 =head1 COMMAND OPTIONS
61 =item B<-inform DER|PEM>
63 This specifies the input format. The B<DER> option uses an ASN1 DER encoded
64 form compatible with the PKCS#10. The B<PEM> form is the default format: it
65 consists of the B<DER> format base64 encoded with additional header and
68 =item B<-outform DER|PEM>
70 This specifies the output format, the options have the same meaning as the
75 This specifies the input filename to read a request from or standard input
76 if this option is not specified. A request is only read if the creation
77 options (B<-new> and B<-newkey>) are not specified.
81 the input file password source. For more information about the format of B<arg>
82 see the B<PASS PHRASE ARGUMENTS> section in L<openssl(1)|openssl(1)>.
84 =item B<-out filename>
86 This specifies the output filename to write to or standard output by
91 the output file password source. For more information about the format of B<arg>
92 see the B<PASS PHRASE ARGUMENTS> section in L<openssl(1)|openssl(1)>.
96 prints out the certificate request in text form.
100 prints out the request subject (or certificate subject if B<-x509> is
105 outputs the public key.
109 this option prevents output of the encoded version of the request.
113 this option prints out the value of the modulus of the public key
114 contained in the request.
118 verifies the signature on the request.
122 this option generates a new certificate request. It will prompt
123 the user for the relevant field values. The actual fields
124 prompted for and their maximum and minimum sizes are specified
125 in the configuration file and any requested extensions.
127 If the B<-key> option is not used it will generate a new RSA private
128 key using information specified in the configuration file.
132 Replaces subject field of input request with specified data and outputs
133 modified request. The arg must be formatted as
134 I</type0=value0/type1=value1/type2=...>,
135 characters may be escaped by \ (backslash), no spaces are skipped.
137 =item B<-rand file(s)>
139 a file or files containing random data used to seed the random number
140 generator, or an EGD socket (see L<RAND_egd(3)|RAND_egd(3)>).
141 Multiple files can be specified separated by a OS-dependent character.
142 The separator is B<;> for MS-Windows, B<,> for OpenVMS, and B<:> for
147 this option creates a new certificate request and a new private
148 key. The argument takes one of several forms. B<rsa:nbits>, where
149 B<nbits> is the number of bits, generates an RSA key B<nbits>
150 in size. If B<nbits> is omitted, i.e. B<-newkey rsa> specified,
151 the default key size, specified in the configuration file is used.
153 All other algorithms support the B<-newkey alg:file> form, where file may be
154 an algorithm parameter file, created by the B<genpkey -genparam> command
155 or and X.509 certificate for a key with approriate algorithm.
157 B<param:file> generates a key using the parameter file or certificate B<file>,
158 the algorithm is determined by the parameters. B<algname:file> use algorithm
159 B<algname> and parameter file B<file>: the two algorithms must match or an
160 error occurs. B<algname> just uses algorithm B<algname>, and parameters,
161 if neccessary should be specified via B<-pkeyopt> parameter.
163 B<dsa:filename> generates a DSA key using the parameters
164 in the file B<filename>. B<ec:filename> generates EC key (usable both with
165 ECDSA or ECDH algorithms), B<gost2001:filename> generates GOST R
166 34.10-2001 key (requires B<ccgost> engine configured in the configuration
167 file). If just B<gost2001> is specified a parameter set should be
168 specified by B<-pkeyopt paramset:X>
171 =item B<-pkeyopt opt:value>
173 set the public key algorithm option B<opt> to B<value>. The precise set of
174 options supported depends on the public key algorithm used and its
175 implementation. See B<KEY GENERATION OPTIONS> in the B<genpkey> manual page
178 =item B<-key filename>
180 This specifies the file to read the private key from. It also
181 accepts PKCS#8 format private keys for PEM format files.
183 =item B<-keyform PEM|DER>
185 the format of the private key file specified in the B<-key>
186 argument. PEM is the default.
188 =item B<-keyout filename>
190 this gives the filename to write the newly created private key to.
191 If this option is not specified then the filename present in the
192 configuration file is used.
196 if this option is specified then if a private key is created it
197 will not be encrypted.
201 this specifies the message digest to sign the request with (such as
202 B<-md5>, B<-sha1>). This overrides the digest algorithm specified in
203 the configuration file.
205 Some public key algorithms may override this choice. For instance, DSA
206 signatures always use SHA1, GOST R 34.10 signatures always use
207 GOST R 34.11-94 (B<-md_gost94>).
209 =item B<-config filename>
211 this allows an alternative configuration file to be specified,
212 this overrides the compile time filename or any specified in
213 the B<OPENSSL_CONF> environment variable.
217 sets subject name for new request or supersedes the subject name
218 when processing a request.
219 The arg must be formatted as I</type0=value0/type1=value1/type2=...>,
220 characters may be escaped by \ (backslash), no spaces are skipped.
222 =item B<-multivalue-rdn>
224 this option causes the -subj argument to be interpreted with full
225 support for multivalued RDNs. Example:
227 I</DC=org/DC=OpenSSL/DC=users/UID=123456+CN=John Doe>
229 If -multi-rdn is not used then the UID value is I<123456+CN=John Doe>.
233 this option outputs a self signed certificate instead of a certificate
234 request. This is typically used to generate a test certificate or
235 a self signed root CA. The extensions added to the certificate
236 (if any) are specified in the configuration file. Unless specified
237 using the B<set_serial> option, a large random number will be used for
242 when the B<-x509> option is being used this specifies the number of
243 days to certify the certificate for. The default is 30 days.
245 =item B<-set_serial n>
247 serial number to use when outputting a self signed certificate. This
248 may be specified as a decimal value or a hex value if preceded by B<0x>.
249 It is possible to use negative serial numbers but this is not recommended.
251 =item B<-extensions section>
253 =item B<-reqexts section>
255 these options specify alternative sections to include certificate
256 extensions (if the B<-x509> option is present) or certificate
257 request extensions. This allows several different sections to
258 be used in the same configuration file to specify requests for
259 a variety of purposes.
263 this option causes field values to be interpreted as UTF8 strings, by
264 default they are interpreted as ASCII. This means that the field
265 values, whether prompted from a terminal or obtained from a
266 configuration file, must be valid UTF8 strings.
268 =item B<-nameopt option>
270 option which determines how the subject or issuer names are displayed. The
271 B<option> argument can be a single option or multiple options separated by
272 commas. Alternatively the B<-nameopt> switch may be used more than once to
273 set multiple options. See the L<x509(1)|x509(1)> manual page for details.
277 customise the output format used with B<-text>. The B<option> argument can be
278 a single option or multiple options separated by commas.
280 See discission of the B<-certopt> parameter in the L<B<x509>|x509(1)>
284 =item B<-asn1-kludge>
286 by default the B<req> command outputs certificate requests containing
287 no attributes in the correct PKCS#10 format. However certain CAs will only
288 accept requests containing no attributes in an invalid form: this
289 option produces this invalid format.
291 More precisely the B<Attributes> in a PKCS#10 certificate request
292 are defined as a B<SET OF Attribute>. They are B<not OPTIONAL> so
293 if no attributes are present then they should be encoded as an
294 empty B<SET OF>. The invalid form does not include the empty
295 B<SET OF> whereas the correct form does.
297 It should be noted that very few CAs still require the use of this option.
299 =item B<-no-asn1-kludge>
301 Reverses effect of B<-asn1-kludge>
305 Adds the word B<NEW> to the PEM file header and footer lines on the outputted
306 request. Some software (Netscape certificate server) and some CAs need this.
310 non-interactive mode.
314 print extra details about the operations being performed.
318 specifying an engine (by its unique B<id> string) will cause B<req>
319 to attempt to obtain a functional reference to the specified engine,
320 thus initialising it if needed. The engine will then be set as the default
321 for all available algorithms.
323 =item B<-keygen_engine id>
325 specifies an engine (by its unique B<id> string) which would be used
326 for key generation operations.
330 =head1 CONFIGURATION FILE FORMAT
332 The configuration options are specified in the B<req> section of
333 the configuration file. As with all configuration files if no
334 value is specified in the specific section (i.e. B<req>) then
335 the initial unnamed or B<default> section is searched too.
337 The options available are described in detail below.
341 =item B<input_password output_password>
343 The passwords for the input private key file (if present) and
344 the output private key file (if one will be created). The
345 command line options B<passin> and B<passout> override the
346 configuration file values.
348 =item B<default_bits>
350 Specifies the default key size in bits.
352 This option is used in conjunction with the B<-new> option to generate
353 a new key. It can be overridden by specifying an explicit key size in
354 the B<-newkey> option. The smallest accepted key size is 512 bits. If
355 no key size is specified then 2048 bits is used.
357 =item B<default_keyfile>
359 This is the default filename to write a private key to. If not
360 specified the key is written to standard output. This can be
361 overridden by the B<-keyout> option.
365 This specifies a file containing additional B<OBJECT IDENTIFIERS>.
366 Each line of the file should consist of the numerical form of the
367 object identifier followed by white space then the short name followed
368 by white space and finally the long name.
372 This specifies a section in the configuration file containing extra
373 object identifiers. Each line should consist of the short name of the
374 object identifier followed by B<=> and the numerical form. The short
375 and long names are the same when this option is used.
379 This specifies a filename in which random number seed information is
380 placed and read from, or an EGD socket (see L<RAND_egd(3)|RAND_egd(3)>).
381 It is used for private key generation.
385 If this is set to B<no> then if a private key is generated it is
386 B<not> encrypted. This is equivalent to the B<-nodes> command line
387 option. For compatibility B<encrypt_rsa_key> is an equivalent option.
391 This option specifies the digest algorithm to use. Possible values
392 include B<md5 sha1 mdc2>. If not present then MD5 is used. This
393 option can be overridden on the command line.
397 This option masks out the use of certain string types in certain
398 fields. Most users will not need to change this option.
400 It can be set to several values B<default> which is also the default
401 option uses PrintableStrings, T61Strings and BMPStrings if the
402 B<pkix> value is used then only PrintableStrings and BMPStrings will
403 be used. This follows the PKIX recommendation in RFC2459. If the
404 B<utf8only> option is used then only UTF8Strings will be used: this
405 is the PKIX recommendation in RFC2459 after 2003. Finally the B<nombstr>
406 option just uses PrintableStrings and T61Strings: certain software has
407 problems with BMPStrings and UTF8Strings: in particular Netscape.
409 =item B<req_extensions>
411 this specifies the configuration file section containing a list of
412 extensions to add to the certificate request. It can be overridden
413 by the B<-reqexts> command line switch. See the
414 L<x509v3_config(5)|x509v3_config(5)> manual page for details of the
415 extension section format.
417 =item B<x509_extensions>
419 this specifies the configuration file section containing a list of
420 extensions to add to certificate generated when the B<-x509> switch
421 is used. It can be overridden by the B<-extensions> command line switch.
425 if set to the value B<no> this disables prompting of certificate fields
426 and just takes values from the config file directly. It also changes the
427 expected format of the B<distinguished_name> and B<attributes> sections.
431 if set to the value B<yes> then field values to be interpreted as UTF8
432 strings, by default they are interpreted as ASCII. This means that
433 the field values, whether prompted from a terminal or obtained from a
434 configuration file, must be valid UTF8 strings.
438 this specifies the section containing any request attributes: its format
439 is the same as B<distinguished_name>. Typically these may contain the
440 challengePassword or unstructuredName types. They are currently ignored
441 by OpenSSL's request signing utilities but some CAs might want them.
443 =item B<distinguished_name>
445 This specifies the section containing the distinguished name fields to
446 prompt for when generating a certificate or certificate request. The format
447 is described in the next section.
451 =head1 DISTINGUISHED NAME AND ATTRIBUTE SECTION FORMAT
453 There are two separate formats for the distinguished name and attribute
454 sections. If the B<prompt> option is set to B<no> then these sections
455 just consist of field names and values: for example,
459 emailAddress=someone@somewhere.org
461 This allows external programs (e.g. GUI based) to generate a template file
462 with all the field names and values and just pass it to B<req>. An example
463 of this kind of configuration file is contained in the B<EXAMPLES> section.
465 Alternatively if the B<prompt> option is absent or not set to B<no> then the
466 file contains field prompting information. It consists of lines of the form:
469 fieldName_default="default field value"
473 "fieldName" is the field name being used, for example commonName (or CN).
474 The "prompt" string is used to ask the user to enter the relevant
475 details. If the user enters nothing then the default value is used if no
476 default value is present then the field is omitted. A field can
477 still be omitted if a default value is present if the user just
478 enters the '.' character.
480 The number of characters entered must be between the fieldName_min and
481 fieldName_max limits: there may be additional restrictions based
482 on the field being used (for example countryName can only ever be
483 two characters long and must fit in a PrintableString).
485 Some fields (such as organizationName) can be used more than once
486 in a DN. This presents a problem because configuration files will
487 not recognize the same name occurring twice. To avoid this problem
488 if the fieldName contains some characters followed by a full stop
489 they will be ignored. So for example a second organizationName can
490 be input by calling it "1.organizationName".
492 The actual permitted field names are any object identifier short or
493 long names. These are compiled into OpenSSL and include the usual
494 values such as commonName, countryName, localityName, organizationName,
495 organizationalUnitName, stateOrProvinceName. Additionally emailAddress
496 is include as well as name, surname, givenName initials and dnQualifier.
498 Additional object identifiers can be defined with the B<oid_file> or
499 B<oid_section> options in the configuration file. Any additional fields
500 will be treated as though they were a DirectoryString.
505 Examine and verify certificate request:
507 openssl req -in req.pem -text -verify -noout
509 Create a private key and then generate a certificate request from it:
511 openssl genrsa -out key.pem 2048
512 openssl req -new -key key.pem -out req.pem
514 The same but just using req:
516 openssl req -newkey rsa:2048 -keyout key.pem -out req.pem
518 Generate a self signed root certificate:
520 openssl req -x509 -newkey rsa:2048 -keyout key.pem -out req.pem
522 Example of a file pointed to by the B<oid_file> option:
524 1.2.3.4 shortName A longer Name
525 1.2.3.6 otherName Other longer Name
527 Example of a section pointed to by B<oid_section> making use of variable
531 testoid2=${testoid1}.6
533 Sample configuration file prompting for field values:
537 default_keyfile = privkey.pem
538 distinguished_name = req_distinguished_name
539 attributes = req_attributes
540 x509_extensions = v3_ca
542 dirstring_type = nobmp
544 [ req_distinguished_name ]
545 countryName = Country Name (2 letter code)
546 countryName_default = AU
550 localityName = Locality Name (eg, city)
552 organizationalUnitName = Organizational Unit Name (eg, section)
554 commonName = Common Name (eg, YOUR name)
557 emailAddress = Email Address
558 emailAddress_max = 40
561 challengePassword = A challenge password
562 challengePassword_min = 4
563 challengePassword_max = 20
567 subjectKeyIdentifier=hash
568 authorityKeyIdentifier=keyid:always,issuer:always
569 basicConstraints = CA:true
571 Sample configuration containing all field values:
574 RANDFILE = $ENV::HOME/.rnd
578 default_keyfile = keyfile.pem
579 distinguished_name = req_distinguished_name
580 attributes = req_attributes
582 output_password = mypass
584 [ req_distinguished_name ]
586 ST = Test State or Province
588 O = Organization Name
589 OU = Organizational Unit Name
591 emailAddress = test@email.address
594 challengePassword = A challenge password
599 The header and footer lines in the B<PEM> format are normally:
601 -----BEGIN CERTIFICATE REQUEST-----
602 -----END CERTIFICATE REQUEST-----
604 some software (some versions of Netscape certificate server) instead needs:
606 -----BEGIN NEW CERTIFICATE REQUEST-----
607 -----END NEW CERTIFICATE REQUEST-----
609 which is produced with the B<-newhdr> option but is otherwise compatible.
610 Either form is accepted transparently on input.
612 The certificate requests generated by B<Xenroll> with MSIE have extensions
613 added. It includes the B<keyUsage> extension which determines the type of
614 key (signature only or general purpose) and any additional OIDs entered
615 by the script in an extendedKeyUsage extension.
619 The following messages are frequently asked about:
621 Using configuration from /some/path/openssl.cnf
622 Unable to load config info
624 This is followed some time later by...
626 unable to find 'distinguished_name' in config
627 problems making Certificate Request
629 The first error message is the clue: it can't find the configuration
630 file! Certain operations (like examining a certificate request) don't
631 need a configuration file so its use isn't enforced. Generation of
632 certificates or requests however does need a configuration file. This
633 could be regarded as a bug.
635 Another puzzling message is this:
640 this is displayed when no attributes are present and the request includes
641 the correct empty B<SET OF> structure (the DER encoding of which is 0xa0
642 0x00). If you just see:
646 then the B<SET OF> is missing and the encoding is technically invalid (but
647 it is tolerated). See the description of the command line option B<-asn1-kludge>
648 for more information.
650 =head1 ENVIRONMENT VARIABLES
652 The variable B<OPENSSL_CONF> if defined allows an alternative configuration
653 file location to be specified, it will be overridden by the B<-config> command
654 line switch if it is present. For compatibility reasons the B<SSLEAY_CONF>
655 environment variable serves the same purpose but its use is discouraged.
659 OpenSSL's handling of T61Strings (aka TeletexStrings) is broken: it effectively
660 treats them as ISO-8859-1 (Latin 1), Netscape and MSIE have similar behaviour.
661 This can cause problems if you need characters that aren't available in
662 PrintableStrings and you don't want to or can't use BMPStrings.
664 As a consequence of the T61String handling the only correct way to represent
665 accented characters in OpenSSL is to use a BMPString: unfortunately Netscape
666 currently chokes on these. If you have to use accented characters with Netscape
667 and MSIE then you currently need to use the invalid T61String form.
669 The current prompting is not very friendly. It doesn't allow you to confirm what
670 you've just entered. Other things like extensions in certificate requests are
671 statically defined in the configuration file. Some of these: like an email
672 address in subjectAltName should be input by the user.
676 L<x509(1)|x509(1)>, L<ca(1)|ca(1)>, L<genrsa(1)|genrsa(1)>,
677 L<gendsa(1)|gendsa(1)>, L<config(5)|config(5)>,
678 L<x509v3_config(5)|x509v3_config(5)>