6 req - PKCS#10 certificate request and certificate generating utility.
30 [B<-[md5|sha1|md2|mdc2]>]
38 [B<-extensions section>]
47 The B<req> command primarily creates and processes certificate requests
48 in PKCS#10 format. It can additionally create self signed certificates
49 for use as root CAs for example.
51 =head1 COMMAND OPTIONS
55 =item B<-inform DER|PEM>
57 This specifies the input format. The B<DER> option uses an ASN1 DER encoded
58 form compatible with the PKCS#10. The B<PEM> form is the default format: it
59 consists of the B<DER> format base64 encoded with additional header and
62 =item B<-outform DER|PEM>
64 This specifies the output format, the options have the same meaning as the
69 This specifies the input filename to read a request from or standard input
70 if this option is not specified. A request is only read if the creation
71 options (B<-new> and B<-newkey>) are not specified.
75 the input file password source. For more information about the format of B<arg>
76 see the B<PASS PHRASE ARGUMENTS> section in L<openssl(1)|openssl(1)>.
78 =item B<-out filename>
80 This specifies the output filename to write to or standard output by
85 the output file password source. For more information about the format of B<arg>
86 see the B<PASS PHRASE ARGUMENTS> section in L<openssl(1)|openssl(1)>.
90 prints out the certificate request in text form.
94 outputs the public key.
98 this option prevents output of the encoded version of the request.
102 this option prints out the value of the modulus of the public key
103 contained in the request.
107 verifies the signature on the request.
111 this option generates a new certificate request. It will prompt
112 the user for the relevant field values. The actual fields
113 prompted for and their maximum and minimum sizes are specified
114 in the configuration file and any requested extensions.
116 If the B<-key> option is not used it will generate a new RSA private
117 key using information specified in the configuration file.
119 =item B<-rand file(s)>
121 a file or files containing random data used to seed the random number
122 generator, or an EGD socket (see L<RAND_egd(3)|RAND_egd(3)>).
123 Multiple files can be specified separated by a OS-dependent character.
124 The separator is B<;> for MS-Windows, B<,> for OpenVMS, and B<:> for
129 this option creates a new certificate request and a new private
130 key. The argument takes one of two forms. B<rsa:nbits>, where
131 B<nbits> is the number of bits, generates an RSA key B<nbits>
132 in size. B<dsa:filename> generates a DSA key using the parameters
133 in the file B<filename>.
135 =item B<-key filename>
137 This specifies the file to read the private key from. It also
138 accepts PKCS#8 format private keys for PEM format files.
140 =item B<-keyform PEM|DER>
142 the format of the private key file specified in the B<-key>
143 argument. PEM is the default.
145 =item B<-keyout filename>
147 this gives the filename to write the newly created private key to.
148 If this option is not specified then the filename present in the
149 configuration file is used.
153 if this option is specified then if a private key is created it
154 will not be encrypted.
156 =item B<-[md5|sha1|md2|mdc2]>
158 this specifies the message digest to sign the request with. This
159 overrides the digest algorithm specified in the configuration file.
160 This option is ignored for DSA requests: they always use SHA1.
162 =item B<-config filename>
164 this allows an alternative configuration file to be specified,
165 this overrides the compile time filename or any specified in
166 the B<OPENSSL_CONF> environment variable.
170 sets subject name for new request or supersedes the subject name
171 when processing a request.
172 The arg must be formatted as I</type0=value0/type1=value1/type2=...>,
173 characters may be escaped by \ (backslash), no spaces are skipped.
177 this option outputs a self signed certificate instead of a certificate
178 request. This is typically used to generate a test certificate or
179 a self signed root CA. The extensions added to the certificate
180 (if any) are specified in the configuration file. Unless specified
181 using the B<set_serial> option B<0> will be used for the serial
186 when the B<-x509> option is being used this specifies the number of
187 days to certify the certificate for. The default is 30 days.
189 =item B<-set_serial n>
191 serial number to use when outputting a self signed certificate. This
192 may be specified as a decimal value or a hex value if preceded by B<0x>.
193 It is possible to use negative serial numbers but this is not recommended.
195 =item B<-extensions section>
197 =item B<-reqexts section>
199 these options specify alternative sections to include certificate
200 extensions (if the B<-x509> option is present) or certificate
201 request extensions. This allows several different sections to
202 be used in the same configuration file to specify requests for
203 a variety of purposes.
207 this option causes field values to be interpreted as UTF8 strings, by
208 default they are interpreted as ASCII. This means that the field
209 values, whether prompted from a terminal or obtained from a
210 configuration file, must be valid UTF8 strings.
212 =item B<-nameopt option>
214 option which determines how the subject or issuer names are displayed. The
215 B<option> argument can be a single option or multiple options separated by
216 commas. Alternatively the B<-nameopt> switch may be used more than once to
217 set multiple options. See the L<x509(1)|x509(1)> manual page for details.
219 =item B<-asn1-kludge>
221 by default the B<req> command outputs certificate requests containing
222 no attributes in the correct PKCS#10 format. However certain CAs will only
223 accept requests containing no attributes in an invalid form: this
224 option produces this invalid format.
226 More precisely the B<Attributes> in a PKCS#10 certificate request
227 are defined as a B<SET OF Attribute>. They are B<not OPTIONAL> so
228 if no attributes are present then they should be encoded as an
229 empty B<SET OF>. The invalid form does not include the empty
230 B<SET OF> whereas the correct form does.
232 It should be noted that very few CAs still require the use of this option.
236 Adds the word B<NEW> to the PEM file header and footer lines on the outputed
237 request. Some software (Netscape certificate server) and some CAs need this.
241 non-interactive mode.
245 print extra details about the operations being performed.
249 =head1 CONFIGURATION FILE FORMAT
251 The configuration options are specified in the B<req> section of
252 the configuration file. As with all configuration files if no
253 value is specified in the specific section (i.e. B<req>) then
254 the initial unnamed or B<default> section is searched too.
256 The options available are described in detail below.
260 =item B<input_password output_password>
262 The passwords for the input private key file (if present) and
263 the output private key file (if one will be created). The
264 command line options B<passin> and B<passout> override the
265 configuration file values.
267 =item B<default_bits>
269 This specifies the default key size in bits. If not specified then
270 512 is used. It is used if the B<-new> option is used. It can be
271 overridden by using the B<-newkey> option.
273 =item B<default_keyfile>
275 This is the default filename to write a private key to. If not
276 specified the key is written to standard output. This can be
277 overridden by the B<-keyout> option.
281 This specifies a file containing additional B<OBJECT IDENTIFIERS>.
282 Each line of the file should consist of the numerical form of the
283 object identifier followed by white space then the short name followed
284 by white space and finally the long name.
288 This specifies a section in the configuration file containing extra
289 object identifiers. Each line should consist of the short name of the
290 object identifier followed by B<=> and the numerical form. The short
291 and long names are the same when this option is used.
295 This specifies a filename in which random number seed information is
296 placed and read from, or an EGD socket (see L<RAND_egd(3)|RAND_egd(3)>).
297 It is used for private key generation.
301 If this is set to B<no> then if a private key is generated it is
302 B<not> encrypted. This is equivalent to the B<-nodes> command line
303 option. For compatibility B<encrypt_rsa_key> is an equivalent option.
307 This option specifies the digest algorithm to use. Possible values
308 include B<md5 sha1 mdc2>. If not present then MD5 is used. This
309 option can be overridden on the command line.
313 This option masks out the use of certain string types in certain
314 fields. Most users will not need to change this option.
316 It can be set to several values B<default> which is also the default
317 option uses PrintableStrings, T61Strings and BMPStrings if the
318 B<pkix> value is used then only PrintableStrings and BMPStrings will
319 be used. This follows the PKIX recommendation in RFC2459. If the
320 B<utf8only> option is used then only UTF8Strings will be used: this
321 is the PKIX recommendation in RFC2459 after 2003. Finally the B<nombstr>
322 option just uses PrintableStrings and T61Strings: certain software has
323 problems with BMPStrings and UTF8Strings: in particular Netscape.
325 =item B<req_extensions>
327 this specifies the configuration file section containing a list of
328 extensions to add to the certificate request. It can be overridden
329 by the B<-reqexts> command line switch.
331 =item B<x509_extensions>
333 this specifies the configuration file section containing a list of
334 extensions to add to certificate generated when the B<-x509> switch
335 is used. It can be overridden by the B<-extensions> command line switch.
339 if set to the value B<no> this disables prompting of certificate fields
340 and just takes values from the config file directly. It also changes the
341 expected format of the B<distinguished_name> and B<attributes> sections.
345 if set to the value B<yes> then field values to be interpreted as UTF8
346 strings, by default they are interpreted as ASCII. This means that
347 the field values, whether prompted from a terminal or obtained from a
348 configuration file, must be valid UTF8 strings.
352 this specifies the section containing any request attributes: its format
353 is the same as B<distinguished_name>. Typically these may contain the
354 challengePassword or unstructuredName types. They are currently ignored
355 by OpenSSL's request signing utilities but some CAs might want them.
357 =item B<distinguished_name>
359 This specifies the section containing the distinguished name fields to
360 prompt for when generating a certificate or certificate request. The format
361 is described in the next section.
365 =head1 DISTINGUISHED NAME AND ATTRIBUTE SECTION FORMAT
367 There are two separate formats for the distinguished name and attribute
368 sections. If the B<prompt> option is set to B<no> then these sections
369 just consist of field names and values: for example,
373 emailAddress=someone@somewhere.org
375 This allows external programs (e.g. GUI based) to generate a template file
376 with all the field names and values and just pass it to B<req>. An example
377 of this kind of configuration file is contained in the B<EXAMPLES> section.
379 Alternatively if the B<prompt> option is absent or not set to B<no> then the
380 file contains field prompting information. It consists of lines of the form:
383 fieldName_default="default field value"
387 "fieldName" is the field name being used, for example commonName (or CN).
388 The "prompt" string is used to ask the user to enter the relevant
389 details. If the user enters nothing then the default value is used if no
390 default value is present then the field is omitted. A field can
391 still be omitted if a default value is present if the user just
392 enters the '.' character.
394 The number of characters entered must be between the fieldName_min and
395 fieldName_max limits: there may be additional restrictions based
396 on the field being used (for example countryName can only ever be
397 two characters long and must fit in a PrintableString).
399 Some fields (such as organizationName) can be used more than once
400 in a DN. This presents a problem because configuration files will
401 not recognize the same name occurring twice. To avoid this problem
402 if the fieldName contains some characters followed by a full stop
403 they will be ignored. So for example a second organizationName can
404 be input by calling it "1.organizationName".
406 The actual permitted field names are any object identifier short or
407 long names. These are compiled into OpenSSL and include the usual
408 values such as commonName, countryName, localityName, organizationName,
409 organizationUnitName, stateOrProvinceName. Additionally emailAddress
410 is include as well as name, surname, givenName initials and dnQualifier.
412 Additional object identifiers can be defined with the B<oid_file> or
413 B<oid_section> options in the configuration file. Any additional fields
414 will be treated as though they were a DirectoryString.
419 Examine and verify certificate request:
421 openssl req -in req.pem -text -verify -noout
423 Create a private key and then generate a certificate request from it:
425 openssl genrsa -out key.pem 1024
426 openssl req -new -key key.pem -out req.pem
428 The same but just using req:
430 openssl req -newkey rsa:1024 -keyout key.pem -out req.pem
432 Generate a self signed root certificate:
434 openssl req -x509 -newkey rsa:1024 -keyout key.pem -out req.pem
436 Example of a file pointed to by the B<oid_file> option:
438 1.2.3.4 shortName A longer Name
439 1.2.3.6 otherName Other longer Name
441 Example of a section pointed to by B<oid_section> making use of variable
445 testoid2=${testoid1}.6
447 Sample configuration file prompting for field values:
451 default_keyfile = privkey.pem
452 distinguished_name = req_distinguished_name
453 attributes = req_attributes
454 x509_extensions = v3_ca
456 dirstring_type = nobmp
458 [ req_distinguished_name ]
459 countryName = Country Name (2 letter code)
460 countryName_default = AU
464 localityName = Locality Name (eg, city)
466 organizationalUnitName = Organizational Unit Name (eg, section)
468 commonName = Common Name (eg, YOUR name)
471 emailAddress = Email Address
472 emailAddress_max = 40
475 challengePassword = A challenge password
476 challengePassword_min = 4
477 challengePassword_max = 20
481 subjectKeyIdentifier=hash
482 authorityKeyIdentifier=keyid:always,issuer:always
483 basicConstraints = CA:true
485 Sample configuration containing all field values:
488 RANDFILE = $ENV::HOME/.rnd
492 default_keyfile = keyfile.pem
493 distinguished_name = req_distinguished_name
494 attributes = req_attributes
496 output_password = mypass
498 [ req_distinguished_name ]
500 ST = Test State or Province
502 O = Organization Name
503 OU = Organizational Unit Name
505 emailAddress = test@email.address
508 challengePassword = A challenge password
513 The header and footer lines in the B<PEM> format are normally:
515 -----BEGIN CERTIFICATE REQUEST-----
516 -----END CERTIFICATE REQUEST-----
518 some software (some versions of Netscape certificate server) instead needs:
520 -----BEGIN NEW CERTIFICATE REQUEST-----
521 -----END NEW CERTIFICATE REQUEST-----
523 which is produced with the B<-newhdr> option but is otherwise compatible.
524 Either form is accepted transparently on input.
526 The certificate requests generated by B<Xenroll> with MSIE have extensions
527 added. It includes the B<keyUsage> extension which determines the type of
528 key (signature only or general purpose) and any additional OIDs entered
529 by the script in an extendedKeyUsage extension.
533 The following messages are frequently asked about:
535 Using configuration from /some/path/openssl.cnf
536 Unable to load config info
538 This is followed some time later by...
540 unable to find 'distinguished_name' in config
541 problems making Certificate Request
543 The first error message is the clue: it can't find the configuration
544 file! Certain operations (like examining a certificate request) don't
545 need a configuration file so its use isn't enforced. Generation of
546 certificates or requests however does need a configuration file. This
547 could be regarded as a bug.
549 Another puzzling message is this:
554 this is displayed when no attributes are present and the request includes
555 the correct empty B<SET OF> structure (the DER encoding of which is 0xa0
556 0x00). If you just see:
560 then the B<SET OF> is missing and the encoding is technically invalid (but
561 it is tolerated). See the description of the command line option B<-asn1-kludge>
562 for more information.
564 =head1 ENVIRONMENT VARIABLES
566 The variable B<OPENSSL_CONF> if defined allows an alternative configuration
567 file location to be specified, it will be overridden by the B<-config> command
568 line switch if it is present. For compatibility reasons the B<SSLEAY_CONF>
569 environment variable serves the same purpose but its use is discouraged.
573 OpenSSL's handling of T61Strings (aka TeletexStrings) is broken: it effectively
574 treats them as ISO-8859-1 (Latin 1), Netscape and MSIE have similar behaviour.
575 This can cause problems if you need characters that aren't available in
576 PrintableStrings and you don't want to or can't use BMPStrings.
578 As a consequence of the T61String handling the only correct way to represent
579 accented characters in OpenSSL is to use a BMPString: unfortunately Netscape
580 currently chokes on these. If you have to use accented characters with Netscape
581 and MSIE then you currently need to use the invalid T61String form.
583 The current prompting is not very friendly. It doesn't allow you to confirm what
584 you've just entered. Other things like extensions in certificate requests are
585 statically defined in the configuration file. Some of these: like an email
586 address in subjectAltName should be input by the user.
590 L<x509(1)|x509(1)>, L<ca(1)|ca(1)>, L<genrsa(1)|genrsa(1)>,
591 L<gendsa(1)|gendsa(1)>, L<config(5)|config(5)>