6 req - PKCS#10 certificate request and certificate generating utility.
30 [B<-[md5|sha1|md2|mdc2]>]
39 [B<-extensions section>]
49 The B<req> command primarily creates and processes certificate requests
50 in PKCS#10 format. It can additionally create self signed certificates
51 for use as root CAs for example.
53 =head1 COMMAND OPTIONS
57 =item B<-inform DER|PEM>
59 This specifies the input format. The B<DER> option uses an ASN1 DER encoded
60 form compatible with the PKCS#10. The B<PEM> form is the default format: it
61 consists of the B<DER> format base64 encoded with additional header and
64 =item B<-outform DER|PEM>
66 This specifies the output format, the options have the same meaning as the
71 This specifies the input filename to read a request from or standard input
72 if this option is not specified. A request is only read if the creation
73 options (B<-new> and B<-newkey>) are not specified.
77 the input file password source. For more information about the format of B<arg>
78 see the B<PASS PHRASE ARGUMENTS> section in L<openssl(1)|openssl(1)>.
80 =item B<-out filename>
82 This specifies the output filename to write to or standard output by
87 the output file password source. For more information about the format of B<arg>
88 see the B<PASS PHRASE ARGUMENTS> section in L<openssl(1)|openssl(1)>.
92 prints out the certificate request in text form.
96 outputs the public key.
100 this option prevents output of the encoded version of the request.
104 this option prints out the value of the modulus of the public key
105 contained in the request.
109 verifies the signature on the request.
113 this option generates a new certificate request. It will prompt
114 the user for the relevant field values. The actual fields
115 prompted for and their maximum and minimum sizes are specified
116 in the configuration file and any requested extensions.
118 If the B<-key> option is not used it will generate a new RSA private
119 key using information specified in the configuration file.
121 =item B<-rand file(s)>
123 a file or files containing random data used to seed the random number
124 generator, or an EGD socket (see L<RAND_egd(3)|RAND_egd(3)>).
125 Multiple files can be specified separated by a OS-dependent character.
126 The separator is B<;> for MS-Windows, B<,> for OpenVMS, and B<:> for
131 this option creates a new certificate request and a new private
132 key. The argument takes one of two forms. B<rsa:nbits>, where
133 B<nbits> is the number of bits, generates an RSA key B<nbits>
134 in size. B<dsa:filename> generates a DSA key using the parameters
135 in the file B<filename>.
137 =item B<-key filename>
139 This specifies the file to read the private key from. It also
140 accepts PKCS#8 format private keys for PEM format files.
142 =item B<-keyform PEM|DER>
144 the format of the private key file specified in the B<-key>
145 argument. PEM is the default.
147 =item B<-keyout filename>
149 this gives the filename to write the newly created private key to.
150 If this option is not specified then the filename present in the
151 configuration file is used.
155 if this option is specified then if a private key is created it
156 will not be encrypted.
158 =item B<-[md5|sha1|md2|mdc2]>
160 this specifies the message digest to sign the request with. This
161 overrides the digest algorithm specified in the configuration file.
162 This option is ignored for DSA requests: they always use SHA1.
164 =item B<-config filename>
166 this allows an alternative configuration file to be specified,
167 this overrides the compile time filename or any specified in
168 the B<OPENSSL_CONF> environment variable.
172 sets subject name for new request or supersedes the subject name
173 when processing a request.
174 The arg must be formatted as I</type0=value0/type1=value1/type2=...>,
175 characters may be escaped by \ (backslash), no spaces are skipped.
177 =item B<-multivalue-rdn>
179 this option causes the -subj argument to be interpreted with full
180 support for multivalued RDNs. Example:
182 I</DC=org/DC=OpenSSL/DC=users/UID=123456+CN=John Doe>
184 If -multi-rdn is not used then the UID value is I<123456+CN=John Doe>.
188 this option outputs a self signed certificate instead of a certificate
189 request. This is typically used to generate a test certificate or
190 a self signed root CA. The extensions added to the certificate
191 (if any) are specified in the configuration file. Unless specified
192 using the B<set_serial> option B<0> will be used for the serial
197 when the B<-x509> option is being used this specifies the number of
198 days to certify the certificate for. The default is 30 days.
200 =item B<-set_serial n>
202 serial number to use when outputting a self signed certificate. This
203 may be specified as a decimal value or a hex value if preceded by B<0x>.
204 It is possible to use negative serial numbers but this is not recommended.
206 =item B<-extensions section>
208 =item B<-reqexts section>
210 these options specify alternative sections to include certificate
211 extensions (if the B<-x509> option is present) or certificate
212 request extensions. This allows several different sections to
213 be used in the same configuration file to specify requests for
214 a variety of purposes.
218 this option causes field values to be interpreted as UTF8 strings, by
219 default they are interpreted as ASCII. This means that the field
220 values, whether prompted from a terminal or obtained from a
221 configuration file, must be valid UTF8 strings.
223 =item B<-nameopt option>
225 option which determines how the subject or issuer names are displayed. The
226 B<option> argument can be a single option or multiple options separated by
227 commas. Alternatively the B<-nameopt> switch may be used more than once to
228 set multiple options. See the L<x509(1)|x509(1)> manual page for details.
230 =item B<-asn1-kludge>
232 by default the B<req> command outputs certificate requests containing
233 no attributes in the correct PKCS#10 format. However certain CAs will only
234 accept requests containing no attributes in an invalid form: this
235 option produces this invalid format.
237 More precisely the B<Attributes> in a PKCS#10 certificate request
238 are defined as a B<SET OF Attribute>. They are B<not OPTIONAL> so
239 if no attributes are present then they should be encoded as an
240 empty B<SET OF>. The invalid form does not include the empty
241 B<SET OF> whereas the correct form does.
243 It should be noted that very few CAs still require the use of this option.
247 Adds the word B<NEW> to the PEM file header and footer lines on the outputed
248 request. Some software (Netscape certificate server) and some CAs need this.
252 non-interactive mode.
256 print extra details about the operations being performed.
260 specifying an engine (by it's unique B<id> string) will cause B<req>
261 to attempt to obtain a functional reference to the specified engine,
262 thus initialising it if needed. The engine will then be set as the default
263 for all available algorithms.
267 =head1 CONFIGURATION FILE FORMAT
269 The configuration options are specified in the B<req> section of
270 the configuration file. As with all configuration files if no
271 value is specified in the specific section (i.e. B<req>) then
272 the initial unnamed or B<default> section is searched too.
274 The options available are described in detail below.
278 =item B<input_password output_password>
280 The passwords for the input private key file (if present) and
281 the output private key file (if one will be created). The
282 command line options B<passin> and B<passout> override the
283 configuration file values.
285 =item B<default_bits>
287 This specifies the default key size in bits. If not specified then
288 512 is used. It is used if the B<-new> option is used. It can be
289 overridden by using the B<-newkey> option.
291 =item B<default_keyfile>
293 This is the default filename to write a private key to. If not
294 specified the key is written to standard output. This can be
295 overridden by the B<-keyout> option.
299 This specifies a file containing additional B<OBJECT IDENTIFIERS>.
300 Each line of the file should consist of the numerical form of the
301 object identifier followed by white space then the short name followed
302 by white space and finally the long name.
306 This specifies a section in the configuration file containing extra
307 object identifiers. Each line should consist of the short name of the
308 object identifier followed by B<=> and the numerical form. The short
309 and long names are the same when this option is used.
313 This specifies a filename in which random number seed information is
314 placed and read from, or an EGD socket (see L<RAND_egd(3)|RAND_egd(3)>).
315 It is used for private key generation.
319 If this is set to B<no> then if a private key is generated it is
320 B<not> encrypted. This is equivalent to the B<-nodes> command line
321 option. For compatibility B<encrypt_rsa_key> is an equivalent option.
325 This option specifies the digest algorithm to use. Possible values
326 include B<md5 sha1 mdc2>. If not present then MD5 is used. This
327 option can be overridden on the command line.
331 This option masks out the use of certain string types in certain
332 fields. Most users will not need to change this option.
334 It can be set to several values B<default> which is also the default
335 option uses PrintableStrings, T61Strings and BMPStrings if the
336 B<pkix> value is used then only PrintableStrings and BMPStrings will
337 be used. This follows the PKIX recommendation in RFC2459. If the
338 B<utf8only> option is used then only UTF8Strings will be used: this
339 is the PKIX recommendation in RFC2459 after 2003. Finally the B<nombstr>
340 option just uses PrintableStrings and T61Strings: certain software has
341 problems with BMPStrings and UTF8Strings: in particular Netscape.
343 =item B<req_extensions>
345 this specifies the configuration file section containing a list of
346 extensions to add to the certificate request. It can be overridden
347 by the B<-reqexts> command line switch.
349 =item B<x509_extensions>
351 this specifies the configuration file section containing a list of
352 extensions to add to certificate generated when the B<-x509> switch
353 is used. It can be overridden by the B<-extensions> command line switch.
357 if set to the value B<no> this disables prompting of certificate fields
358 and just takes values from the config file directly. It also changes the
359 expected format of the B<distinguished_name> and B<attributes> sections.
363 if set to the value B<yes> then field values to be interpreted as UTF8
364 strings, by default they are interpreted as ASCII. This means that
365 the field values, whether prompted from a terminal or obtained from a
366 configuration file, must be valid UTF8 strings.
370 this specifies the section containing any request attributes: its format
371 is the same as B<distinguished_name>. Typically these may contain the
372 challengePassword or unstructuredName types. They are currently ignored
373 by OpenSSL's request signing utilities but some CAs might want them.
375 =item B<distinguished_name>
377 This specifies the section containing the distinguished name fields to
378 prompt for when generating a certificate or certificate request. The format
379 is described in the next section.
383 =head1 DISTINGUISHED NAME AND ATTRIBUTE SECTION FORMAT
385 There are two separate formats for the distinguished name and attribute
386 sections. If the B<prompt> option is set to B<no> then these sections
387 just consist of field names and values: for example,
391 emailAddress=someone@somewhere.org
393 This allows external programs (e.g. GUI based) to generate a template file
394 with all the field names and values and just pass it to B<req>. An example
395 of this kind of configuration file is contained in the B<EXAMPLES> section.
397 Alternatively if the B<prompt> option is absent or not set to B<no> then the
398 file contains field prompting information. It consists of lines of the form:
401 fieldName_default="default field value"
405 "fieldName" is the field name being used, for example commonName (or CN).
406 The "prompt" string is used to ask the user to enter the relevant
407 details. If the user enters nothing then the default value is used if no
408 default value is present then the field is omitted. A field can
409 still be omitted if a default value is present if the user just
410 enters the '.' character.
412 The number of characters entered must be between the fieldName_min and
413 fieldName_max limits: there may be additional restrictions based
414 on the field being used (for example countryName can only ever be
415 two characters long and must fit in a PrintableString).
417 Some fields (such as organizationName) can be used more than once
418 in a DN. This presents a problem because configuration files will
419 not recognize the same name occurring twice. To avoid this problem
420 if the fieldName contains some characters followed by a full stop
421 they will be ignored. So for example a second organizationName can
422 be input by calling it "1.organizationName".
424 The actual permitted field names are any object identifier short or
425 long names. These are compiled into OpenSSL and include the usual
426 values such as commonName, countryName, localityName, organizationName,
427 organizationUnitName, stateOrProvinceName. Additionally emailAddress
428 is include as well as name, surname, givenName initials and dnQualifier.
430 Additional object identifiers can be defined with the B<oid_file> or
431 B<oid_section> options in the configuration file. Any additional fields
432 will be treated as though they were a DirectoryString.
437 Examine and verify certificate request:
439 openssl req -in req.pem -text -verify -noout
441 Create a private key and then generate a certificate request from it:
443 openssl genrsa -out key.pem 1024
444 openssl req -new -key key.pem -out req.pem
446 The same but just using req:
448 openssl req -newkey rsa:1024 -keyout key.pem -out req.pem
450 Generate a self signed root certificate:
452 openssl req -x509 -newkey rsa:1024 -keyout key.pem -out req.pem
454 Example of a file pointed to by the B<oid_file> option:
456 1.2.3.4 shortName A longer Name
457 1.2.3.6 otherName Other longer Name
459 Example of a section pointed to by B<oid_section> making use of variable
463 testoid2=${testoid1}.6
465 Sample configuration file prompting for field values:
469 default_keyfile = privkey.pem
470 distinguished_name = req_distinguished_name
471 attributes = req_attributes
472 x509_extensions = v3_ca
474 dirstring_type = nobmp
476 [ req_distinguished_name ]
477 countryName = Country Name (2 letter code)
478 countryName_default = AU
482 localityName = Locality Name (eg, city)
484 organizationalUnitName = Organizational Unit Name (eg, section)
486 commonName = Common Name (eg, YOUR name)
489 emailAddress = Email Address
490 emailAddress_max = 40
493 challengePassword = A challenge password
494 challengePassword_min = 4
495 challengePassword_max = 20
499 subjectKeyIdentifier=hash
500 authorityKeyIdentifier=keyid:always,issuer:always
501 basicConstraints = CA:true
503 Sample configuration containing all field values:
506 RANDFILE = $ENV::HOME/.rnd
510 default_keyfile = keyfile.pem
511 distinguished_name = req_distinguished_name
512 attributes = req_attributes
514 output_password = mypass
516 [ req_distinguished_name ]
518 ST = Test State or Province
520 O = Organization Name
521 OU = Organizational Unit Name
523 emailAddress = test@email.address
526 challengePassword = A challenge password
531 The header and footer lines in the B<PEM> format are normally:
533 -----BEGIN CERTIFICATE REQUEST-----
534 -----END CERTIFICATE REQUEST-----
536 some software (some versions of Netscape certificate server) instead needs:
538 -----BEGIN NEW CERTIFICATE REQUEST-----
539 -----END NEW CERTIFICATE REQUEST-----
541 which is produced with the B<-newhdr> option but is otherwise compatible.
542 Either form is accepted transparently on input.
544 The certificate requests generated by B<Xenroll> with MSIE have extensions
545 added. It includes the B<keyUsage> extension which determines the type of
546 key (signature only or general purpose) and any additional OIDs entered
547 by the script in an extendedKeyUsage extension.
551 The following messages are frequently asked about:
553 Using configuration from /some/path/openssl.cnf
554 Unable to load config info
556 This is followed some time later by...
558 unable to find 'distinguished_name' in config
559 problems making Certificate Request
561 The first error message is the clue: it can't find the configuration
562 file! Certain operations (like examining a certificate request) don't
563 need a configuration file so its use isn't enforced. Generation of
564 certificates or requests however does need a configuration file. This
565 could be regarded as a bug.
567 Another puzzling message is this:
572 this is displayed when no attributes are present and the request includes
573 the correct empty B<SET OF> structure (the DER encoding of which is 0xa0
574 0x00). If you just see:
578 then the B<SET OF> is missing and the encoding is technically invalid (but
579 it is tolerated). See the description of the command line option B<-asn1-kludge>
580 for more information.
582 =head1 ENVIRONMENT VARIABLES
584 The variable B<OPENSSL_CONF> if defined allows an alternative configuration
585 file location to be specified, it will be overridden by the B<-config> command
586 line switch if it is present. For compatibility reasons the B<SSLEAY_CONF>
587 environment variable serves the same purpose but its use is discouraged.
591 OpenSSL's handling of T61Strings (aka TeletexStrings) is broken: it effectively
592 treats them as ISO-8859-1 (Latin 1), Netscape and MSIE have similar behaviour.
593 This can cause problems if you need characters that aren't available in
594 PrintableStrings and you don't want to or can't use BMPStrings.
596 As a consequence of the T61String handling the only correct way to represent
597 accented characters in OpenSSL is to use a BMPString: unfortunately Netscape
598 currently chokes on these. If you have to use accented characters with Netscape
599 and MSIE then you currently need to use the invalid T61String form.
601 The current prompting is not very friendly. It doesn't allow you to confirm what
602 you've just entered. Other things like extensions in certificate requests are
603 statically defined in the configuration file. Some of these: like an email
604 address in subjectAltName should be input by the user.
608 L<x509(1)|x509(1)>, L<ca(1)|ca(1)>, L<genrsa(1)|genrsa(1)>,
609 L<gendsa(1)|gendsa(1)>, L<config(5)|config(5)>