6 req - PKCS#10 certificate and certificate generating utility.
28 [B<-[md5|sha1|md2|mdc2]>]
34 [B<-extensions section>]
39 The B<req> command primarily creates and processes certificate requests
40 in PKCS#10 format. It can additionally create self signed certificates
41 for use as root CAs for example.
43 =head1 COMMAND OPTIONS
47 =item B<-inform DER|PEM>
49 This specifies the input format. The B<DER> option uses an ASN1 DER encoded
50 form compatible with the PKCS#10. The B<PEM> form is the default format: it
51 consists of the B<DER> format base64 encoded with additional header and
54 =item B<-outform DER|PEM>
56 This specifies the output format, the options have the same meaning as the
61 This specifies the input filename to read a request from or standard input
62 if this option is not specified. A request is only read if the creation
63 options (B<-new> and B<-newkey>) are not specified.
67 the input file password source. For more information about the format of B<arg>
68 see the B<PASS PHRASE ARGUMENTS> section in L<openssl(1)|openssl(1)>.
70 =item B<-out filename>
72 This specifies the output filename to write to or standard output by
77 the output 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)>.
82 prints out the certificate request in text form.
86 this option prevents output of the encoded version of the request.
90 this option prints out the value of the modulus of the public key
91 contained in the request.
95 verifies the signature on the request.
99 this option generates a new certificate request. It will prompt
100 the user for the relevant field values. The actual fields
101 prompted for and their maximum and minimum sizes are specified
102 in the configuration file and any requested extensions.
104 If the B<-key> option is not used it will generate a new RSA private
105 key using information specified in the configuration file.
109 this option creates a new certificate request and a new private
110 key. The argument takes one of two forms. B<rsa:nbits>, where
111 B<nbits> is the number of bits, generates an RSA key B<nbits>
112 in size. B<dsa:filename> generates a DSA key using the parameters
113 in the file B<filename>.
115 =item B<-key filename>
117 This specifies the file to read the private key from. It also
118 accepts PKCS#8 format private keys for PEM format files.
120 =item B<-keyform PEM|DER>
122 the format of the private key file specified in the B<-key>
123 argument. PEM is the default.
125 =item B<-keyout filename>
127 this gives the filename to write the newly created private key to.
128 If this option is not specified then the filename present in the
129 configuration file is used.
133 if this option is specified then if a private key is created it
134 will not be encrypted.
136 =item B<-[md5|sha1|md2|mdc2]>
138 this specifies the message digest to sign the request with. This
139 overrides the digest algorithm specified in the configuration file.
140 This option is ignored for DSA requests: they always use SHA1.
142 =item B<-config filename>
144 this allows an alternative configuration file to be specified,
145 this overrides the compile time filename or any specified in
146 the B<OPENSSL_CONF> environment variable.
150 this option outputs a self signed certificate instead of a certificate
151 request. This is typically used to generate a test certificate or
152 a self signed root CA. The extensions added to the certificate
153 (if any) are specified in the configuration file.
157 when the B<-x509> option is being used this specifies the number of
158 days to certify the certificate for. The default is 30 days.
160 =item B<-extensions section>
161 =item B<-reqexts section>
163 these options specify alternative sections to include certificate
164 extensions (if the B<-x509> option is present) or certificate
165 request extensions. This allows several different sections to
166 be used in the same configuration file to specify requests for
167 a variety of purposes.
169 =item B<-asn1-kludge>
171 by default the B<req> command outputs certificate requests containing
172 no attributes in the correct PKCS#10 format. However certain CAs will only
173 accept requests containing no attributes in an invalid form: this
174 option produces this invalid format.
176 More precisely the B<Attributes> in a PKCS#10 certificate request
177 are defined as a B<SET OF Attribute>. They are B<not OPTIONAL> so
178 if no attributes are present then they should be encoded as an
179 empty B<SET OF>. The invalid form does not include the empty
180 B<SET OF> whereas the correct form does.
182 It should be noted that very few CAs still require the use of this option.
186 Adds the word B<NEW> to the PEM file header and footer lines on the outputed
187 request. Some software (Netscape certificate server) and some CAs need this.
191 =head1 CONFIGURATION FILE FORMAT
193 The configuration options are specified in the B<req> section of
194 the configuration file. As with all configuration files if no
195 value is specified in the specific section (i.e. B<req>) then
196 the initial unnamed or B<default> section is searched too.
198 The options available are described in detail below.
202 =item B<input_password output_password>
204 The passwords for the input private key file (if present) and
205 the output private key file (if one will be created). The
206 command line options B<passin> and B<passout> override the
207 configuration file values.
209 =item B<default_bits>
211 This specifies the default key size in bits. If not specified then
212 512 is used. It is used if the B<-new> option is used. It can be
213 overridden by using the B<-newkey> option.
215 =item B<default_keyfile>
217 This is the default filename to write a private key to. If not
218 specified the key is written to standard output. This can be
219 overridden by the B<-keyout> option.
223 This specifies a file containing additional B<OBJECT IDENTIFIERS>.
224 Each line of the file should consist of the numerical form of the
225 object identifier followed by white space then the short name followed
226 by white space and finally the long name.
230 This specifies a section in the configuration file containing extra
231 object identifiers. Each line should consist of the short name of the
232 object identifier followed by B<=> and the numerical form. The short
233 and long names are the same when this option is used.
237 This specifies a filename in which random number seed information is
238 placed and read from, or an EGD socket (see L<RAND_egd(3)|RAND_egd(3)>).
239 It is used for private key generation.
243 If this is set to B<no> then if a private key is generated it is
244 B<not> encrypted. This is equivalent to the B<-nodes> command line
245 option. For compatibility B<encrypt_rsa_key> is an equivalent option.
249 This option specifies the digest algorithm to use. Possible values
250 include B<md5 sha1 mdc2>. If not present then MD5 is used. This
251 option can be overridden on the command line.
255 This option masks out the use of certain string types in certain
256 fields. Most users will not need to change this option.
258 It can be set to several values B<default> which is also the default
259 option uses PrintableStrings, T61Strings and BMPStrings if the
260 B<pkix> value is used then only PrintableStrings and BMPStrings will
261 be used. This follows the PKIX recommendation in RFC2459. If the
262 B<utf8only> option is used then only UTF8Strings will be used: this
263 is the PKIX recommendation in RFC2459 after 2003. Finally the B<nombstr>
264 option just uses PrintableStrings and T61Strings: certain software has
265 problems with BMPStrings and UTF8Strings: in particular Netscape.
267 =item B<req_extensions>
269 this specifies the configuration file section containing a list of
270 extensions to add to the certificate request. It can be overridden
271 by the B<-reqexts> command line switch.
273 =item B<x509_extensions>
275 this specifies the configuration file section containing a list of
276 extensions to add to certificate generated when the B<-x509> switch
277 is used. It can be overridden by the B<-extensions> command line switch.
281 if set to the value B<no> this disables prompting of certificate fields
282 and just takes values from the config file directly. It also changes the
283 expected format of the B<distinguished_name> and B<attributes> sections.
287 this specifies the section containing any request attributes: its format
288 is the same as B<distinguished_name>. Typically these may contain the
289 challengePassword or unstructuredName types. They are currently ignored
290 by OpenSSL's request signing utilities but some CAs might want them.
292 =item B<distinguished_name>
294 This specifies the section containing the distinguished name fields to
295 prompt for when generating a certificate or certificate request. The format
296 is described in the next section.
300 =head1 DISTINGUISHED NAME AND ATTRIBUTE SECTION FORMAT
302 There are two separate formats for the distinguished name and attribute
303 sections. If the B<prompt> option is set to B<no> then these sections
304 just consist of field names and values: for example,
308 emailAddress=someone@somewhere.org
310 This allows external programs (e.g. GUI based) to generate a template file
311 with all the field names and values and just pass it to B<req>. An example
312 of this kind of configuration file is contained in the B<EXAMPLES> section.
314 Alternatively if the B<prompt> option is absent or not set to B<no> then the
315 file contains field prompting information. It consists of lines of the form:
318 fieldName_default="default field value"
322 "fieldName" is the field name being used, for example commonName (or CN).
323 The "prompt" string is used to ask the user to enter the relevant
324 details. If the user enters nothing then the default value is used if no
325 default value is present then the field is omitted. A field can
326 still be omitted if a default value is present if the user just
327 enters the '.' character.
329 The number of characters entered must be between the fieldName_min and
330 fieldName_max limits: there may be additional restrictions based
331 on the field being used (for example countryName can only ever be
332 two characters long and must fit in a PrintableString).
334 Some fields (such as organizationName) can be used more than once
335 in a DN. This presents a problem because configuration files will
336 not recognize the same name occurring twice. To avoid this problem
337 if the fieldName contains some characters followed by a full stop
338 they will be ignored. So for example a second organizationName can
339 be input by calling it "1.organizationName".
341 The actual permitted field names are any object identifier short or
342 long names. These are compiled into OpenSSL and include the usual
343 values such as commonName, countryName, localityName, organizationName,
344 organizationUnitName, stateOrPrivinceName. Additionally emailAddress
345 is include as well as name, surname, givenName initials and dnQualifier.
347 Additional object identifiers can be defined with the B<oid_file> or
348 B<oid_section> options in the configuration file. Any additional fields
349 will be treated as though they were a DirectoryString.
354 Examine and verify certificate request:
356 openssl req -in req.pem -text -verify -noout
358 Create a private key and then generate a certificate request from it:
360 openssl genrsa -out key.pem 1024
361 openssl req -new -key key.pem -out req.pem
363 The same but just using req:
365 openssl req -newkey rsa:1024 -keyout key.pem -out req.pem
367 Generate a self signed root certificate:
369 openssl req -x509 -newkey rsa:1024 -keyout key.pem -out req.pem
371 Example of a file pointed to by the B<oid_file> option:
373 1.2.3.4 shortName A longer Name
374 1.2.3.6 otherName Other longer Name
376 Example of a section pointed to by B<oid_section> making use of variable
380 testoid2=${testoid1}.6
382 Sample configuration file prompting for field values:
386 default_keyfile = privkey.pem
387 distinguished_name = req_distinguished_name
388 attributes = req_attributes
389 x509_extensions = v3_ca
391 dirstring_type = nobmp
393 [ req_distinguished_name ]
394 countryName = Country Name (2 letter code)
395 countryName_default = AU
399 localityName = Locality Name (eg, city)
401 organizationalUnitName = Organizational Unit Name (eg, section)
403 commonName = Common Name (eg, YOUR name)
406 emailAddress = Email Address
407 emailAddress_max = 40
410 challengePassword = A challenge password
411 challengePassword_min = 4
412 challengePassword_max = 20
416 subjectKeyIdentifier=hash
417 authorityKeyIdentifier=keyid:always,issuer:always
418 basicConstraints = CA:true
420 Sample configuration containing all field values:
423 RANDFILE = $ENV::HOME/.rnd
427 default_keyfile = keyfile.pem
428 distinguished_name = req_distinguished_name
429 attributes = req_attributes
431 output_password = mypass
433 [ req_distinguished_name ]
435 ST = Test State or Province
437 O = Organization Name
438 OU = Organizational Unit Name
440 emailAddress = test@email.address
443 challengePassword = A challenge password
448 The header and footer lines in the B<PEM> format are normally:
450 -----BEGIN CERTIFICATE REQUEST----
451 -----END CERTIFICATE REQUEST----
453 some software (some versions of Netscape certificate server) instead needs:
455 -----BEGIN NEW CERTIFICATE REQUEST----
456 -----END NEW CERTIFICATE REQUEST----
458 which is produced with the B<-newhdr> option but is otherwise compatible.
459 Either form is accepted transparently on input.
461 The certificate requests generated by B<Xenroll> with MSIE have extensions
462 added. It includes the B<keyUsage> extension which determines the type of
463 key (signature only or general purpose) and any additional OIDs entered
464 by the script in an extendedKeyUsage extension.
468 The following messages are frequently asked about:
470 Using configuration from /some/path/openssl.cnf
471 Unable to load config info
473 This is followed some time later by...
475 unable to find 'distinguished_name' in config
476 problems making Certificate Request
478 The first error message is the clue: it can't find the configuration
479 file! Certain operations (like examining a certificate request) don't
480 need a configuration file so its use isn't enforced. Generation of
481 certificates or requests however does need a configuration file. This
482 could be regarded as a bug.
484 Another puzzling message is this:
489 this is displayed when no attributes are present and the request includes
490 the correct empty B<SET OF> structure (the DER encoding of which is 0xa0
491 0x00). If you just see:
495 then the B<SET OF> is missing and the encoding is technically invalid (but
496 it is tolerated). See the description of the command line option B<-asn1-kludge>
497 for more information.
499 =head1 ENVIRONMENT VARIABLES
501 The variable B<OPENSSL_CONF> if defined allows an alternative configuration
502 file location to be specified, it will be overridden by the B<-config> command
503 line switch if it is present. For compatibility reasons the B<SSLEAY_CONF>
504 environment variable serves the same purpose but its use is discouraged.
508 OpenSSL's handling of T61Strings (aka TeletexStrings) is broken: it effectively
509 treats them as ISO-8859-1 (Latin 1), Netscape and MSIE have similar behaviour.
510 This can cause problems if you need characters that aren't available in
511 PrintableStrings and you don't want to or can't use BMPStrings.
513 As a consequence of the T61String handling the only correct way to represent
514 accented characters in OpenSSL is to use a BMPString: unfortunately Netscape
515 currently chokes on these. If you have to use accented characters with Netscape
516 and MSIE then you currently need to use the invalid T61String form.
518 The current prompting is not very friendly. It doesn't allow you to confirm what
519 you've just entered. Other things like extensions in certificate requests are
520 statically defined in the configuration file. Some of these: like an email
521 address in subjectAltName should be input by the user.
525 L<x509(1)|x509(1)>, L<ca(1)|ca(1)>, L<genrsa(1)|genrsa(1)>,
526 L<gendsa(1)|gendsa(1)>, L<config(5)|config(5)>