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. It is used for private key generation.
242 If this is set to B<no> then if a private key is generated it is
243 B<not> encrypted. This is equivalent to the B<-nodes> command line
244 option. For compatibility B<encrypt_rsa_key> is an equivalent option.
248 This option specifies the digest algorithm to use. Possible values
249 include B<md5 sha1 mdc2>. If not present then MD5 is used. This
250 option can be overridden on the command line.
254 This option masks out the use of certain string types in certain
255 fields. Most users will not need to change this option.
257 It can be set to several values B<default> which is also the default
258 option uses PrintableStrings, T61Strings and BMPStrings if the
259 B<pkix> value is used then only PrintableStrings and BMPStrings will
260 be used. This follows the PKIX recommendation in RFC2459. If the
261 B<utf8only> option is used then only UTF8Strings will be used: this
262 is the PKIX recommendation in RFC2459 after 2003. Finally the B<nombstr>
263 option just uses PrintableStrings and T61Strings: certain software has
264 problems with BMPStrings and UTF8Strings: in particular Netscape.
266 =item B<req_extensions>
268 this specifies the configuration file section containing a list of
269 extensions to add to the certificate request. It can be overridden
270 by the B<-reqexts> command line switch.
272 =item B<x509_extensions>
274 this specifies the configuration file section containing a list of
275 extensions to add to certificate generated when the B<-x509> switch
276 is used. It can be overridden by the B<-extensions> command line switch.
280 if set to the value B<no> this disables prompting of certificate fields
281 and just takes values from the config file directly. It also changes the
282 expected format of the B<distinguished_name> and B<attributes> sections.
286 this specifies the section containing any request attributes: its format
287 is the same as B<distinguished_name>. Typically these may contain the
288 challengePassword or unstructuredName types. They are currently ignored
289 by OpenSSL's request signing utilities but some CAs might want them.
291 =item B<distinguished_name>
293 This specifies the section containing the distinguished name fields to
294 prompt for when generating a certificate or certificate request. The format
295 is described in the next section.
299 =head1 DISTINGUISHED NAME AND ATTRIBUTE SECTION FORMAT
301 There are two separate formats for the distinguished name and attribute
302 sections. If the B<prompt> option is set to B<no> then these sections
303 just consist of field names and values: for example,
307 emailAddress=someone@somewhere.org
309 This allows external programs (e.g. GUI based) to generate a template file
310 with all the field names and values and just pass it to B<req>. An example
311 of this kind of configuration file is contained in the B<EXAMPLES> section.
313 Alternatively if the B<prompt> option is absent or not set to B<no> then the
314 file contains field prompting information. It consists of lines of the form:
317 fieldName_default="default field value"
321 "fieldName" is the field name being used, for example commonName (or CN).
322 The "prompt" string is used to ask the user to enter the relevant
323 details. If the user enters nothing then the default value is used if no
324 default value is present then the field is omitted. A field can
325 still be omitted if a default value is present if the user just
326 enters the '.' character.
328 The number of characters entered must be between the fieldName_min and
329 fieldName_max limits: there may be additional restrictions based
330 on the field being used (for example countryName can only ever be
331 two characters long and must fit in a PrintableString).
333 Some fields (such as organizationName) can be used more than once
334 in a DN. This presents a problem because configuration files will
335 not recognize the same name occurring twice. To avoid this problem
336 if the fieldName contains some characters followed by a full stop
337 they will be ignored. So for example a second organizationName can
338 be input by calling it "1.organizationName".
340 The actual permitted field names are any object identifier short or
341 long names. These are compiled into OpenSSL and include the usual
342 values such as commonName, countryName, localityName, organizationName,
343 organizationUnitName, stateOrPrivinceName. Additionally emailAddress
344 is include as well as name, surname, givenName initials and dnQualifier.
346 Additional object identifiers can be defined with the B<oid_file> or
347 B<oid_section> options in the configuration file. Any additional fields
348 will be treated as though they were a DirectoryString.
353 Examine and verify certificate request:
355 openssl req -in req.pem -text -verify -noout
357 Create a private key and then generate a certificate request from it:
359 openssl genrsa -out key.pem 1024
360 openssl req -new -key key.pem -out req.pem
362 The same but just using req:
364 openssl req -newkey rsa:1024 -keyout key.pem -out req.pem
366 Generate a self signed root certificate:
368 openssl req -x509 -newkey rsa:1024 -keyout key.pem -out req.pem
370 Example of a file pointed to by the B<oid_file> option:
372 1.2.3.4 shortName A longer Name
373 1.2.3.6 otherName Other longer Name
375 Example of a section pointed to by B<oid_section> making use of variable
379 testoid2=${testoid1}.6
381 Sample configuration file prompting for field values:
385 default_keyfile = privkey.pem
386 distinguished_name = req_distinguished_name
387 attributes = req_attributes
388 x509_extensions = v3_ca
390 dirstring_type = nobmp
392 [ req_distinguished_name ]
393 countryName = Country Name (2 letter code)
394 countryName_default = AU
398 localityName = Locality Name (eg, city)
400 organizationalUnitName = Organizational Unit Name (eg, section)
402 commonName = Common Name (eg, YOUR name)
405 emailAddress = Email Address
406 emailAddress_max = 40
409 challengePassword = A challenge password
410 challengePassword_min = 4
411 challengePassword_max = 20
415 subjectKeyIdentifier=hash
416 authorityKeyIdentifier=keyid:always,issuer:always
417 basicConstraints = CA:true
419 Sample configuration containing all field values:
422 RANDFILE = $ENV::HOME/.rnd
426 default_keyfile = keyfile.pem
427 distinguished_name = req_distinguished_name
428 attributes = req_attributes
430 output_password = mypass
432 [ req_distinguished_name ]
434 ST = Test State or Province
436 O = Organization Name
437 OU = Organizational Unit Name
439 emailAddress = test@email.address
442 challengePassword = A challenge password
447 The header and footer lines in the B<PEM> format are normally:
449 -----BEGIN CERTIFICATE REQUEST----
450 -----END CERTIFICATE REQUEST----
452 some software (some versions of Netscape certificate server) instead needs:
454 -----BEGIN NEW CERTIFICATE REQUEST----
455 -----END NEW CERTIFICATE REQUEST----
457 which is produced with the B<-newhdr> option but is otherwise compatible.
458 Either form is accepted transparently on input.
460 The certificate requests generated by B<Xenroll> with MSIE have extensions
461 added. It includes the B<keyUsage> extension which determines the type of
462 key (signature only or general purpose) and any additional OIDs entered
463 by the script in an extendedKeyUsage extension.
467 The following messages are frequently asked about:
469 Using configuration from /some/path/openssl.cnf
470 Unable to load config info
472 This is followed some time later by...
474 unable to find 'distinguished_name' in config
475 problems making Certificate Request
477 The first error message is the clue: it can't find the configuration
478 file! Certain operations (like examining a certificate request) don't
479 need a configuration file so its use isn't enforced. Generation of
480 certificates or requests however does need a configuration file. This
481 could be regarded as a bug.
483 Another puzzling message is this:
488 this is displayed when no attributes are present and the request includes
489 the correct empty B<SET OF> structure (the DER encoding of which is 0xa0
490 0x00). If you just see:
494 then the B<SET OF> is missing and the encoding is technically invalid (but
495 it is tolerated). See the description of the command line option B<-asn1-kludge>
496 for more information.
498 =head1 ENVIRONMENT VARIABLES
500 The variable B<OPENSSL_CONF> if defined allows an alternative configuration
501 file location to be specified, it will be overridden by the B<-config> command
502 line switch if it is present. For compatibility reasons the B<SSLEAY_CONF>
503 environment variable serves the same purpose but its use is discouraged.
507 OpenSSL's handling of T61Strings (aka TeletexStrings) is broken: it effectively
508 treats them as ISO-8859-1 (Latin 1), Netscape and MSIE have similar behaviour.
509 This can cause problems if you need characters that aren't available in
510 PrintableStrings and you don't want to or can't use BMPStrings.
512 As a consequence of the T61String handling the only correct way to represent
513 accented characters in OpenSSL is to use a BMPString: unfortunately Netscape
514 currently chokes on these. If you have to use accented characters with Netscape
515 and MSIE then you currently need to use the invalid T61String form.
517 The current prompting is not very friendly. It doesn't allow you to confirm what
518 you've just entered. Other things like extensions in certificate requests are
519 statically defined in the configuration file. Some of these: like an email
520 address in subjectAltName should be input by the user.
524 L<x509(1)|x509(1)>, L<ca(1)|ca(1)>, L<genrsa(1)|genrsa(1)>,
525 L<gendsa(1)|gendsa(1)>, L<config(5)|config(5)>