6 req - PKCS#10 certificate and certificate generating utility.
29 [B<-[md5|sha1|md2|mdc2]>]
35 [B<-extensions section>]
40 The B<req> command primarily creates and processes certificate requests
41 in PKCS#10 format. It can additionally create self signed certificates
42 for use as root CAs for example.
44 =head1 COMMAND OPTIONS
48 =item B<-inform DER|PEM>
50 This specifies the input format. The B<DER> option uses an ASN1 DER encoded
51 form compatible with the PKCS#10. The B<PEM> form is the default format: it
52 consists of the B<DER> format base64 encoded with additional header and
55 =item B<-outform DER|PEM>
57 This specifies the output format, the options have the same meaning as the
62 This specifies the input filename to read a request from or standard input
63 if this option is not specified. A request is only read if the creation
64 options (B<-new> and B<-newkey>) are not specified.
68 the input file password source. For more information about the format of B<arg>
69 see the B<PASS PHRASE ARGUMENTS> section in L<openssl(1)|openssl(1)>.
71 =item B<-out filename>
73 This specifies the output filename to write to or standard output by
78 the output file password source. For more information about the format of B<arg>
79 see the B<PASS PHRASE ARGUMENTS> section in L<openssl(1)|openssl(1)>.
83 prints out the certificate request in text form.
87 this option prevents output of the encoded version of the request.
91 this option prints out the value of the modulus of the public key
92 contained in the request.
96 verifies the signature on the request.
100 this option generates a new certificate request. It will prompt
101 the user for the relevant field values. The actual fields
102 prompted for and their maximum and minimum sizes are specified
103 in the configuration file and any requested extensions.
105 If the B<-key> option is not used it will generate a new RSA private
106 key using information specified in the configuration file.
108 =item B<-rand file(s)>
110 a file or files containing random data used to seed the random number
111 generator, or an EGD socket (see L<RAND_egd(3)|RAND_egd(3)>).
112 Multiple files can be specified separated by a OS-dependent character.
113 The separator is B<;> for MS-Windows, B<,> for OpenVMS, and B<:> for
118 this option creates a new certificate request and a new private
119 key. The argument takes one of two forms. B<rsa:nbits>, where
120 B<nbits> is the number of bits, generates an RSA key B<nbits>
121 in size. B<dsa:filename> generates a DSA key using the parameters
122 in the file B<filename>.
124 =item B<-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.
129 =item B<-keyform PEM|DER>
131 the format of the private key file specified in the B<-key>
132 argument. PEM is the default.
134 =item B<-keyout filename>
136 this gives the filename to write the newly created private key to.
137 If this option is not specified then the filename present in the
138 configuration file is used.
142 if this option is specified then if a private key is created it
143 will not be encrypted.
145 =item B<-[md5|sha1|md2|mdc2]>
147 this specifies the message digest to sign the request with. This
148 overrides the digest algorithm specified in the configuration file.
149 This option is ignored for DSA requests: they always use SHA1.
151 =item B<-config filename>
153 this allows an alternative configuration file to be specified,
154 this overrides the compile time filename or any specified in
155 the B<OPENSSL_CONF> environment variable.
159 this option outputs a self signed certificate instead of a certificate
160 request. This is typically used to generate a test certificate or
161 a self signed root CA. The extensions added to the certificate
162 (if any) are specified in the configuration file.
166 when the B<-x509> option is being used this specifies the number of
167 days to certify the certificate for. The default is 30 days.
169 =item B<-extensions section>
171 =item B<-reqexts section>
173 these options specify alternative sections to include certificate
174 extensions (if the B<-x509> option is present) or certificate
175 request extensions. This allows several different sections to
176 be used in the same configuration file to specify requests for
177 a variety of purposes.
179 =item B<-asn1-kludge>
181 by default the B<req> command outputs certificate requests containing
182 no attributes in the correct PKCS#10 format. However certain CAs will only
183 accept requests containing no attributes in an invalid form: this
184 option produces this invalid format.
186 More precisely the B<Attributes> in a PKCS#10 certificate request
187 are defined as a B<SET OF Attribute>. They are B<not OPTIONAL> so
188 if no attributes are present then they should be encoded as an
189 empty B<SET OF>. The invalid form does not include the empty
190 B<SET OF> whereas the correct form does.
192 It should be noted that very few CAs still require the use of this option.
196 Adds the word B<NEW> to the PEM file header and footer lines on the outputed
197 request. Some software (Netscape certificate server) and some CAs need this.
201 =head1 CONFIGURATION FILE FORMAT
203 The configuration options are specified in the B<req> section of
204 the configuration file. As with all configuration files if no
205 value is specified in the specific section (i.e. B<req>) then
206 the initial unnamed or B<default> section is searched too.
208 The options available are described in detail below.
212 =item B<input_password output_password>
214 The passwords for the input private key file (if present) and
215 the output private key file (if one will be created). The
216 command line options B<passin> and B<passout> override the
217 configuration file values.
219 =item B<default_bits>
221 This specifies the default key size in bits. If not specified then
222 512 is used. It is used if the B<-new> option is used. It can be
223 overridden by using the B<-newkey> option.
225 =item B<default_keyfile>
227 This is the default filename to write a private key to. If not
228 specified the key is written to standard output. This can be
229 overridden by the B<-keyout> option.
233 This specifies a file containing additional B<OBJECT IDENTIFIERS>.
234 Each line of the file should consist of the numerical form of the
235 object identifier followed by white space then the short name followed
236 by white space and finally the long name.
240 This specifies a section in the configuration file containing extra
241 object identifiers. Each line should consist of the short name of the
242 object identifier followed by B<=> and the numerical form. The short
243 and long names are the same when this option is used.
247 This specifies a filename in which random number seed information is
248 placed and read from, or an EGD socket (see L<RAND_egd(3)|RAND_egd(3)>).
249 It is used for private key generation.
253 If this is set to B<no> then if a private key is generated it is
254 B<not> encrypted. This is equivalent to the B<-nodes> command line
255 option. For compatibility B<encrypt_rsa_key> is an equivalent option.
259 This option specifies the digest algorithm to use. Possible values
260 include B<md5 sha1 mdc2>. If not present then MD5 is used. This
261 option can be overridden on the command line.
265 This option masks out the use of certain string types in certain
266 fields. Most users will not need to change this option.
268 It can be set to several values B<default> which is also the default
269 option uses PrintableStrings, T61Strings and BMPStrings if the
270 B<pkix> value is used then only PrintableStrings and BMPStrings will
271 be used. This follows the PKIX recommendation in RFC2459. If the
272 B<utf8only> option is used then only UTF8Strings will be used: this
273 is the PKIX recommendation in RFC2459 after 2003. Finally the B<nombstr>
274 option just uses PrintableStrings and T61Strings: certain software has
275 problems with BMPStrings and UTF8Strings: in particular Netscape.
277 =item B<req_extensions>
279 this specifies the configuration file section containing a list of
280 extensions to add to the certificate request. It can be overridden
281 by the B<-reqexts> command line switch.
283 =item B<x509_extensions>
285 this specifies the configuration file section containing a list of
286 extensions to add to certificate generated when the B<-x509> switch
287 is used. It can be overridden by the B<-extensions> command line switch.
291 if set to the value B<no> this disables prompting of certificate fields
292 and just takes values from the config file directly. It also changes the
293 expected format of the B<distinguished_name> and B<attributes> sections.
297 this specifies the section containing any request attributes: its format
298 is the same as B<distinguished_name>. Typically these may contain the
299 challengePassword or unstructuredName types. They are currently ignored
300 by OpenSSL's request signing utilities but some CAs might want them.
302 =item B<distinguished_name>
304 This specifies the section containing the distinguished name fields to
305 prompt for when generating a certificate or certificate request. The format
306 is described in the next section.
310 =head1 DISTINGUISHED NAME AND ATTRIBUTE SECTION FORMAT
312 There are two separate formats for the distinguished name and attribute
313 sections. If the B<prompt> option is set to B<no> then these sections
314 just consist of field names and values: for example,
318 emailAddress=someone@somewhere.org
320 This allows external programs (e.g. GUI based) to generate a template file
321 with all the field names and values and just pass it to B<req>. An example
322 of this kind of configuration file is contained in the B<EXAMPLES> section.
324 Alternatively if the B<prompt> option is absent or not set to B<no> then the
325 file contains field prompting information. It consists of lines of the form:
328 fieldName_default="default field value"
332 "fieldName" is the field name being used, for example commonName (or CN).
333 The "prompt" string is used to ask the user to enter the relevant
334 details. If the user enters nothing then the default value is used if no
335 default value is present then the field is omitted. A field can
336 still be omitted if a default value is present if the user just
337 enters the '.' character.
339 The number of characters entered must be between the fieldName_min and
340 fieldName_max limits: there may be additional restrictions based
341 on the field being used (for example countryName can only ever be
342 two characters long and must fit in a PrintableString).
344 Some fields (such as organizationName) can be used more than once
345 in a DN. This presents a problem because configuration files will
346 not recognize the same name occurring twice. To avoid this problem
347 if the fieldName contains some characters followed by a full stop
348 they will be ignored. So for example a second organizationName can
349 be input by calling it "1.organizationName".
351 The actual permitted field names are any object identifier short or
352 long names. These are compiled into OpenSSL and include the usual
353 values such as commonName, countryName, localityName, organizationName,
354 organizationUnitName, stateOrPrivinceName. Additionally emailAddress
355 is include as well as name, surname, givenName initials and dnQualifier.
357 Additional object identifiers can be defined with the B<oid_file> or
358 B<oid_section> options in the configuration file. Any additional fields
359 will be treated as though they were a DirectoryString.
364 Examine and verify certificate request:
366 openssl req -in req.pem -text -verify -noout
368 Create a private key and then generate a certificate request from it:
370 openssl genrsa -out key.pem 1024
371 openssl req -new -key key.pem -out req.pem
373 The same but just using req:
375 openssl req -newkey rsa:1024 -keyout key.pem -out req.pem
377 Generate a self signed root certificate:
379 openssl req -x509 -newkey rsa:1024 -keyout key.pem -out req.pem
381 Example of a file pointed to by the B<oid_file> option:
383 1.2.3.4 shortName A longer Name
384 1.2.3.6 otherName Other longer Name
386 Example of a section pointed to by B<oid_section> making use of variable
390 testoid2=${testoid1}.6
392 Sample configuration file prompting for field values:
396 default_keyfile = privkey.pem
397 distinguished_name = req_distinguished_name
398 attributes = req_attributes
399 x509_extensions = v3_ca
401 dirstring_type = nobmp
403 [ req_distinguished_name ]
404 countryName = Country Name (2 letter code)
405 countryName_default = AU
409 localityName = Locality Name (eg, city)
411 organizationalUnitName = Organizational Unit Name (eg, section)
413 commonName = Common Name (eg, YOUR name)
416 emailAddress = Email Address
417 emailAddress_max = 40
420 challengePassword = A challenge password
421 challengePassword_min = 4
422 challengePassword_max = 20
426 subjectKeyIdentifier=hash
427 authorityKeyIdentifier=keyid:always,issuer:always
428 basicConstraints = CA:true
430 Sample configuration containing all field values:
433 RANDFILE = $ENV::HOME/.rnd
437 default_keyfile = keyfile.pem
438 distinguished_name = req_distinguished_name
439 attributes = req_attributes
441 output_password = mypass
443 [ req_distinguished_name ]
445 ST = Test State or Province
447 O = Organization Name
448 OU = Organizational Unit Name
450 emailAddress = test@email.address
453 challengePassword = A challenge password
458 The header and footer lines in the B<PEM> format are normally:
460 -----BEGIN CERTIFICATE REQUEST----
461 -----END CERTIFICATE REQUEST----
463 some software (some versions of Netscape certificate server) instead needs:
465 -----BEGIN NEW CERTIFICATE REQUEST----
466 -----END NEW CERTIFICATE REQUEST----
468 which is produced with the B<-newhdr> option but is otherwise compatible.
469 Either form is accepted transparently on input.
471 The certificate requests generated by B<Xenroll> with MSIE have extensions
472 added. It includes the B<keyUsage> extension which determines the type of
473 key (signature only or general purpose) and any additional OIDs entered
474 by the script in an extendedKeyUsage extension.
478 The following messages are frequently asked about:
480 Using configuration from /some/path/openssl.cnf
481 Unable to load config info
483 This is followed some time later by...
485 unable to find 'distinguished_name' in config
486 problems making Certificate Request
488 The first error message is the clue: it can't find the configuration
489 file! Certain operations (like examining a certificate request) don't
490 need a configuration file so its use isn't enforced. Generation of
491 certificates or requests however does need a configuration file. This
492 could be regarded as a bug.
494 Another puzzling message is this:
499 this is displayed when no attributes are present and the request includes
500 the correct empty B<SET OF> structure (the DER encoding of which is 0xa0
501 0x00). If you just see:
505 then the B<SET OF> is missing and the encoding is technically invalid (but
506 it is tolerated). See the description of the command line option B<-asn1-kludge>
507 for more information.
509 =head1 ENVIRONMENT VARIABLES
511 The variable B<OPENSSL_CONF> if defined allows an alternative configuration
512 file location to be specified, it will be overridden by the B<-config> command
513 line switch if it is present. For compatibility reasons the B<SSLEAY_CONF>
514 environment variable serves the same purpose but its use is discouraged.
518 OpenSSL's handling of T61Strings (aka TeletexStrings) is broken: it effectively
519 treats them as ISO-8859-1 (Latin 1), Netscape and MSIE have similar behaviour.
520 This can cause problems if you need characters that aren't available in
521 PrintableStrings and you don't want to or can't use BMPStrings.
523 As a consequence of the T61String handling the only correct way to represent
524 accented characters in OpenSSL is to use a BMPString: unfortunately Netscape
525 currently chokes on these. If you have to use accented characters with Netscape
526 and MSIE then you currently need to use the invalid T61String form.
528 The current prompting is not very friendly. It doesn't allow you to confirm what
529 you've just entered. Other things like extensions in certificate requests are
530 statically defined in the configuration file. Some of these: like an email
531 address in subjectAltName should be input by the user.
535 L<x509(1)|x509(1)>, L<ca(1)|ca(1)>, L<genrsa(1)|genrsa(1)>,
536 L<gendsa(1)|gendsa(1)>, L<config(5)|config(5)>