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>
162 =item B<-reqexts section>
164 these options specify alternative sections to include certificate
165 extensions (if the B<-x509> option is present) or certificate
166 request extensions. This allows several different sections to
167 be used in the same configuration file to specify requests for
168 a variety of purposes.
170 =item B<-asn1-kludge>
172 by default the B<req> command outputs certificate requests containing
173 no attributes in the correct PKCS#10 format. However certain CAs will only
174 accept requests containing no attributes in an invalid form: this
175 option produces this invalid format.
177 More precisely the B<Attributes> in a PKCS#10 certificate request
178 are defined as a B<SET OF Attribute>. They are B<not OPTIONAL> so
179 if no attributes are present then they should be encoded as an
180 empty B<SET OF>. The invalid form does not include the empty
181 B<SET OF> whereas the correct form does.
183 It should be noted that very few CAs still require the use of this option.
187 Adds the word B<NEW> to the PEM file header and footer lines on the outputed
188 request. Some software (Netscape certificate server) and some CAs need this.
192 =head1 CONFIGURATION FILE FORMAT
194 The configuration options are specified in the B<req> section of
195 the configuration file. As with all configuration files if no
196 value is specified in the specific section (i.e. B<req>) then
197 the initial unnamed or B<default> section is searched too.
199 The options available are described in detail below.
203 =item B<input_password output_password>
205 The passwords for the input private key file (if present) and
206 the output private key file (if one will be created). The
207 command line options B<passin> and B<passout> override the
208 configuration file values.
210 =item B<default_bits>
212 This specifies the default key size in bits. If not specified then
213 512 is used. It is used if the B<-new> option is used. It can be
214 overridden by using the B<-newkey> option.
216 =item B<default_keyfile>
218 This is the default filename to write a private key to. If not
219 specified the key is written to standard output. This can be
220 overridden by the B<-keyout> option.
224 This specifies a file containing additional B<OBJECT IDENTIFIERS>.
225 Each line of the file should consist of the numerical form of the
226 object identifier followed by white space then the short name followed
227 by white space and finally the long name.
231 This specifies a section in the configuration file containing extra
232 object identifiers. Each line should consist of the short name of the
233 object identifier followed by B<=> and the numerical form. The short
234 and long names are the same when this option is used.
238 This specifies a filename in which random number seed information is
239 placed and read from, or an EGD socket (see L<RAND_egd(3)|RAND_egd(3)>).
240 It is used for private key generation.
244 If this is set to B<no> then if a private key is generated it is
245 B<not> encrypted. This is equivalent to the B<-nodes> command line
246 option. For compatibility B<encrypt_rsa_key> is an equivalent option.
250 This option specifies the digest algorithm to use. Possible values
251 include B<md5 sha1 mdc2>. If not present then MD5 is used. This
252 option can be overridden on the command line.
256 This option masks out the use of certain string types in certain
257 fields. Most users will not need to change this option.
259 It can be set to several values B<default> which is also the default
260 option uses PrintableStrings, T61Strings and BMPStrings if the
261 B<pkix> value is used then only PrintableStrings and BMPStrings will
262 be used. This follows the PKIX recommendation in RFC2459. If the
263 B<utf8only> option is used then only UTF8Strings will be used: this
264 is the PKIX recommendation in RFC2459 after 2003. Finally the B<nombstr>
265 option just uses PrintableStrings and T61Strings: certain software has
266 problems with BMPStrings and UTF8Strings: in particular Netscape.
268 =item B<req_extensions>
270 this specifies the configuration file section containing a list of
271 extensions to add to the certificate request. It can be overridden
272 by the B<-reqexts> command line switch.
274 =item B<x509_extensions>
276 this specifies the configuration file section containing a list of
277 extensions to add to certificate generated when the B<-x509> switch
278 is used. It can be overridden by the B<-extensions> command line switch.
282 if set to the value B<no> this disables prompting of certificate fields
283 and just takes values from the config file directly. It also changes the
284 expected format of the B<distinguished_name> and B<attributes> sections.
288 this specifies the section containing any request attributes: its format
289 is the same as B<distinguished_name>. Typically these may contain the
290 challengePassword or unstructuredName types. They are currently ignored
291 by OpenSSL's request signing utilities but some CAs might want them.
293 =item B<distinguished_name>
295 This specifies the section containing the distinguished name fields to
296 prompt for when generating a certificate or certificate request. The format
297 is described in the next section.
301 =head1 DISTINGUISHED NAME AND ATTRIBUTE SECTION FORMAT
303 There are two separate formats for the distinguished name and attribute
304 sections. If the B<prompt> option is set to B<no> then these sections
305 just consist of field names and values: for example,
309 emailAddress=someone@somewhere.org
311 This allows external programs (e.g. GUI based) to generate a template file
312 with all the field names and values and just pass it to B<req>. An example
313 of this kind of configuration file is contained in the B<EXAMPLES> section.
315 Alternatively if the B<prompt> option is absent or not set to B<no> then the
316 file contains field prompting information. It consists of lines of the form:
319 fieldName_default="default field value"
323 "fieldName" is the field name being used, for example commonName (or CN).
324 The "prompt" string is used to ask the user to enter the relevant
325 details. If the user enters nothing then the default value is used if no
326 default value is present then the field is omitted. A field can
327 still be omitted if a default value is present if the user just
328 enters the '.' character.
330 The number of characters entered must be between the fieldName_min and
331 fieldName_max limits: there may be additional restrictions based
332 on the field being used (for example countryName can only ever be
333 two characters long and must fit in a PrintableString).
335 Some fields (such as organizationName) can be used more than once
336 in a DN. This presents a problem because configuration files will
337 not recognize the same name occurring twice. To avoid this problem
338 if the fieldName contains some characters followed by a full stop
339 they will be ignored. So for example a second organizationName can
340 be input by calling it "1.organizationName".
342 The actual permitted field names are any object identifier short or
343 long names. These are compiled into OpenSSL and include the usual
344 values such as commonName, countryName, localityName, organizationName,
345 organizationUnitName, stateOrPrivinceName. Additionally emailAddress
346 is include as well as name, surname, givenName initials and dnQualifier.
348 Additional object identifiers can be defined with the B<oid_file> or
349 B<oid_section> options in the configuration file. Any additional fields
350 will be treated as though they were a DirectoryString.
355 Examine and verify certificate request:
357 openssl req -in req.pem -text -verify -noout
359 Create a private key and then generate a certificate request from it:
361 openssl genrsa -out key.pem 1024
362 openssl req -new -key key.pem -out req.pem
364 The same but just using req:
366 openssl req -newkey rsa:1024 -keyout key.pem -out req.pem
368 Generate a self signed root certificate:
370 openssl req -x509 -newkey rsa:1024 -keyout key.pem -out req.pem
372 Example of a file pointed to by the B<oid_file> option:
374 1.2.3.4 shortName A longer Name
375 1.2.3.6 otherName Other longer Name
377 Example of a section pointed to by B<oid_section> making use of variable
381 testoid2=${testoid1}.6
383 Sample configuration file prompting for field values:
387 default_keyfile = privkey.pem
388 distinguished_name = req_distinguished_name
389 attributes = req_attributes
390 x509_extensions = v3_ca
392 dirstring_type = nobmp
394 [ req_distinguished_name ]
395 countryName = Country Name (2 letter code)
396 countryName_default = AU
400 localityName = Locality Name (eg, city)
402 organizationalUnitName = Organizational Unit Name (eg, section)
404 commonName = Common Name (eg, YOUR name)
407 emailAddress = Email Address
408 emailAddress_max = 40
411 challengePassword = A challenge password
412 challengePassword_min = 4
413 challengePassword_max = 20
417 subjectKeyIdentifier=hash
418 authorityKeyIdentifier=keyid:always,issuer:always
419 basicConstraints = CA:true
421 Sample configuration containing all field values:
424 RANDFILE = $ENV::HOME/.rnd
428 default_keyfile = keyfile.pem
429 distinguished_name = req_distinguished_name
430 attributes = req_attributes
432 output_password = mypass
434 [ req_distinguished_name ]
436 ST = Test State or Province
438 O = Organization Name
439 OU = Organizational Unit Name
441 emailAddress = test@email.address
444 challengePassword = A challenge password
449 The header and footer lines in the B<PEM> format are normally:
451 -----BEGIN CERTIFICATE REQUEST----
452 -----END CERTIFICATE REQUEST----
454 some software (some versions of Netscape certificate server) instead needs:
456 -----BEGIN NEW CERTIFICATE REQUEST----
457 -----END NEW CERTIFICATE REQUEST----
459 which is produced with the B<-newhdr> option but is otherwise compatible.
460 Either form is accepted transparently on input.
462 The certificate requests generated by B<Xenroll> with MSIE have extensions
463 added. It includes the B<keyUsage> extension which determines the type of
464 key (signature only or general purpose) and any additional OIDs entered
465 by the script in an extendedKeyUsage extension.
469 The following messages are frequently asked about:
471 Using configuration from /some/path/openssl.cnf
472 Unable to load config info
474 This is followed some time later by...
476 unable to find 'distinguished_name' in config
477 problems making Certificate Request
479 The first error message is the clue: it can't find the configuration
480 file! Certain operations (like examining a certificate request) don't
481 need a configuration file so its use isn't enforced. Generation of
482 certificates or requests however does need a configuration file. This
483 could be regarded as a bug.
485 Another puzzling message is this:
490 this is displayed when no attributes are present and the request includes
491 the correct empty B<SET OF> structure (the DER encoding of which is 0xa0
492 0x00). If you just see:
496 then the B<SET OF> is missing and the encoding is technically invalid (but
497 it is tolerated). See the description of the command line option B<-asn1-kludge>
498 for more information.
500 =head1 ENVIRONMENT VARIABLES
502 The variable B<OPENSSL_CONF> if defined allows an alternative configuration
503 file location to be specified, it will be overridden by the B<-config> command
504 line switch if it is present. For compatibility reasons the B<SSLEAY_CONF>
505 environment variable serves the same purpose but its use is discouraged.
509 OpenSSL's handling of T61Strings (aka TeletexStrings) is broken: it effectively
510 treats them as ISO-8859-1 (Latin 1), Netscape and MSIE have similar behaviour.
511 This can cause problems if you need characters that aren't available in
512 PrintableStrings and you don't want to or can't use BMPStrings.
514 As a consequence of the T61String handling the only correct way to represent
515 accented characters in OpenSSL is to use a BMPString: unfortunately Netscape
516 currently chokes on these. If you have to use accented characters with Netscape
517 and MSIE then you currently need to use the invalid T61String form.
519 The current prompting is not very friendly. It doesn't allow you to confirm what
520 you've just entered. Other things like extensions in certificate requests are
521 statically defined in the configuration file. Some of these: like an email
522 address in subjectAltName should be input by the user.
526 L<x509(1)|x509(1)>, L<ca(1)|ca(1)>, L<genrsa(1)|genrsa(1)>,
527 L<gendsa(1)|gendsa(1)>, L<config(5)|config(5)>