req.pod 23 KB

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  1. =pod
  2. =head1 NAME
  3. openssl-req,
  4. req - PKCS#10 certificate request and certificate generating utility
  5. =head1 SYNOPSIS
  6. B<openssl> B<req>
  7. [B<-help>]
  8. [B<-inform PEM|DER>]
  9. [B<-outform PEM|DER>]
  10. [B<-in filename>]
  11. [B<-passin arg>]
  12. [B<-out filename>]
  13. [B<-passout arg>]
  14. [B<-text>]
  15. [B<-pubkey>]
  16. [B<-noout>]
  17. [B<-verify>]
  18. [B<-modulus>]
  19. [B<-new>]
  20. [B<-rand file...>]
  21. [B<-writerand file>]
  22. [B<-newkey rsa:bits>]
  23. [B<-newkey alg:file>]
  24. [B<-nodes>]
  25. [B<-key filename>]
  26. [B<-keyform PEM|DER>]
  27. [B<-keyout filename>]
  28. [B<-keygen_engine id>]
  29. [B<-I<digest>>]
  30. [B<-config filename>]
  31. [B<-multivalue-rdn>]
  32. [B<-x509>]
  33. [B<-days n>]
  34. [B<-set_serial n>]
  35. [B<-newhdr>]
  36. [B<-addext ext>]
  37. [B<-extensions section>]
  38. [B<-reqexts section>]
  39. [B<-precert>]
  40. [B<-utf8>]
  41. [B<-nameopt>]
  42. [B<-reqopt>]
  43. [B<-subject>]
  44. [B<-subj arg>]
  45. [B<-sigopt nm:v>]
  46. [B<-batch>]
  47. [B<-verbose>]
  48. [B<-engine id>]
  49. =head1 DESCRIPTION
  50. The B<req> command primarily creates and processes certificate requests
  51. in PKCS#10 format. It can additionally create self signed certificates
  52. for use as root CAs for example.
  53. =head1 OPTIONS
  54. =over 4
  55. =item B<-help>
  56. Print out a usage message.
  57. =item B<-inform DER|PEM>
  58. This specifies the input format. The B<DER> option uses an ASN1 DER encoded
  59. form compatible with the PKCS#10. The B<PEM> form is the default format: it
  60. consists of the B<DER> format base64 encoded with additional header and
  61. footer lines.
  62. =item B<-outform DER|PEM>
  63. This specifies the output format, the options have the same meaning and default
  64. as the B<-inform> option.
  65. =item B<-in filename>
  66. This specifies the input filename to read a request from or standard input
  67. if this option is not specified. A request is only read if the creation
  68. options (B<-new> and B<-newkey>) are not specified.
  69. =item B<-sigopt nm:v>
  70. Pass options to the signature algorithm during sign or verify operations.
  71. Names and values of these options are algorithm-specific.
  72. =item B<-passin arg>
  73. The input file password source. For more information about the format of B<arg>
  74. see the B<PASS PHRASE ARGUMENTS> section in L<openssl(1)>.
  75. =item B<-out filename>
  76. This specifies the output filename to write to or standard output by
  77. default.
  78. =item B<-passout arg>
  79. The output file password source. For more information about the format of B<arg>
  80. see the B<PASS PHRASE ARGUMENTS> section in L<openssl(1)>.
  81. =item B<-text>
  82. Prints out the certificate request in text form.
  83. =item B<-subject>
  84. Prints out the request subject (or certificate subject if B<-x509> is
  85. specified)
  86. =item B<-pubkey>
  87. Outputs the public key.
  88. =item B<-noout>
  89. This option prevents output of the encoded version of the request.
  90. =item B<-modulus>
  91. This option prints out the value of the modulus of the public key
  92. contained in the request.
  93. =item B<-verify>
  94. Verifies the signature on the request.
  95. =item B<-new>
  96. This option generates a new certificate request. It will prompt
  97. the user for the relevant field values. The actual fields
  98. prompted for and their maximum and minimum sizes are specified
  99. in the configuration file and any requested extensions.
  100. If the B<-key> option is not used it will generate a new RSA private
  101. key using information specified in the configuration file.
  102. =item B<-rand file...>
  103. A file or files containing random data used to seed the random number
  104. generator.
  105. Multiple files can be specified separated by an OS-dependent character.
  106. The separator is B<;> for MS-Windows, B<,> for OpenVMS, and B<:> for
  107. all others.
  108. =item [B<-writerand file>]
  109. Writes random data to the specified I<file> upon exit.
  110. This can be used with a subsequent B<-rand> flag.
  111. =item B<-newkey arg>
  112. This option creates a new certificate request and a new private
  113. key. The argument takes one of several forms. B<rsa:nbits>, where
  114. B<nbits> is the number of bits, generates an RSA key B<nbits>
  115. in size. If B<nbits> is omitted, i.e. B<-newkey rsa> specified,
  116. the default key size, specified in the configuration file is used.
  117. All other algorithms support the B<-newkey alg:file> form, where file may be
  118. an algorithm parameter file, created by the B<genpkey -genparam> command
  119. or and X.509 certificate for a key with appropriate algorithm.
  120. B<param:file> generates a key using the parameter file or certificate B<file>,
  121. the algorithm is determined by the parameters. B<algname:file> use algorithm
  122. B<algname> and parameter file B<file>: the two algorithms must match or an
  123. error occurs. B<algname> just uses algorithm B<algname>, and parameters,
  124. if necessary should be specified via B<-pkeyopt> parameter.
  125. B<dsa:filename> generates a DSA key using the parameters
  126. in the file B<filename>. B<ec:filename> generates EC key (usable both with
  127. ECDSA or ECDH algorithms), B<gost2001:filename> generates GOST R
  128. 34.10-2001 key (requires B<ccgost> engine configured in the configuration
  129. file). If just B<gost2001> is specified a parameter set should be
  130. specified by B<-pkeyopt paramset:X>
  131. =item B<-pkeyopt opt:value>
  132. Set the public key algorithm option B<opt> to B<value>. The precise set of
  133. options supported depends on the public key algorithm used and its
  134. implementation. See B<KEY GENERATION OPTIONS> in the B<genpkey> manual page
  135. for more details.
  136. =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.
  139. =item B<-keyform PEM|DER>
  140. The format of the private key file specified in the B<-key>
  141. argument. PEM is the default.
  142. =item B<-keyout filename>
  143. This gives the filename to write the newly created private key to.
  144. If this option is not specified then the filename present in the
  145. configuration file is used.
  146. =item B<-nodes>
  147. If this option is specified then if a private key is created it
  148. will not be encrypted.
  149. =item B<-I<digest>>
  150. This specifies the message digest to sign the request.
  151. Any digest supported by the OpenSSL B<dgst> command can be used.
  152. This overrides the digest algorithm specified in
  153. the configuration file.
  154. Some public key algorithms may override this choice. For instance, DSA
  155. signatures always use SHA1, GOST R 34.10 signatures always use
  156. GOST R 34.11-94 (B<-md_gost94>), Ed25519 and Ed448 never use any digest.
  157. =item B<-config filename>
  158. This allows an alternative configuration file to be specified.
  159. Optional; for a description of the default value,
  160. see L<openssl(1)/COMMAND SUMMARY>.
  161. =item B<-subj arg>
  162. Sets subject name for new request or supersedes the subject name
  163. when processing a request.
  164. The arg must be formatted as I</type0=value0/type1=value1/type2=...>.
  165. Keyword characters may be escaped by \ (backslash), and whitespace is retained.
  166. Empty values are permitted, but the corresponding type will not be included
  167. in the request.
  168. =item B<-multivalue-rdn>
  169. This option causes the -subj argument to be interpreted with full
  170. support for multivalued RDNs. Example:
  171. I</DC=org/DC=OpenSSL/DC=users/UID=123456+CN=John Doe>
  172. If -multi-rdn is not used then the UID value is I<123456+CN=John Doe>.
  173. =item B<-x509>
  174. This option outputs a self signed certificate instead of a certificate
  175. request. This is typically used to generate a test certificate or
  176. a self signed root CA. The extensions added to the certificate
  177. (if any) are specified in the configuration file. Unless specified
  178. using the B<set_serial> option, a large random number will be used for
  179. the serial number.
  180. If existing request is specified with the B<-in> option, it is converted
  181. to the self signed certificate otherwise new request is created.
  182. =item B<-days n>
  183. When the B<-x509> option is being used this specifies the number of
  184. days to certify the certificate for, otherwise it is ignored. B<n> should
  185. be a positive integer. The default is 30 days.
  186. =item B<-set_serial n>
  187. Serial number to use when outputting a self signed certificate. This
  188. may be specified as a decimal value or a hex value if preceded by B<0x>.
  189. =item B<-addext ext>
  190. Add a specific extension to the certificate (if the B<-x509> option is
  191. present) or certificate request. The argument must have the form of
  192. a key=value pair as it would appear in a config file.
  193. This option can be given multiple times.
  194. =item B<-extensions section>
  195. =item B<-reqexts section>
  196. These options specify alternative sections to include certificate
  197. extensions (if the B<-x509> option is present) or certificate
  198. request extensions. This allows several different sections to
  199. be used in the same configuration file to specify requests for
  200. a variety of purposes.
  201. =item B<-precert>
  202. A poison extension will be added to the certificate, making it a
  203. "pre-certificate" (see RFC6962). This can be submitted to Certificate
  204. Transparency logs in order to obtain signed certificate timestamps (SCTs).
  205. These SCTs can then be embedded into the pre-certificate as an extension, before
  206. removing the poison and signing the certificate.
  207. This implies the B<-new> flag.
  208. =item B<-utf8>
  209. This option causes field values to be interpreted as UTF8 strings, by
  210. default they are interpreted as ASCII. This means that the field
  211. values, whether prompted from a terminal or obtained from a
  212. configuration file, must be valid UTF8 strings.
  213. =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)> manual page for details.
  218. =item B<-reqopt>
  219. Customise the output format used with B<-text>. The B<option> argument can be
  220. a single option or multiple options separated by commas.
  221. See discussion of the B<-certopt> parameter in the L<x509(1)>
  222. command.
  223. =item B<-newhdr>
  224. Adds the word B<NEW> to the PEM file header and footer lines on the outputted
  225. request. Some software (Netscape certificate server) and some CAs need this.
  226. =item B<-batch>
  227. Non-interactive mode.
  228. =item B<-verbose>
  229. Print extra details about the operations being performed.
  230. =item B<-engine id>
  231. Specifying an engine (by its unique B<id> string) will cause B<req>
  232. to attempt to obtain a functional reference to the specified engine,
  233. thus initialising it if needed. The engine will then be set as the default
  234. for all available algorithms.
  235. =item B<-keygen_engine id>
  236. Specifies an engine (by its unique B<id> string) which would be used
  237. for key generation operations.
  238. =back
  239. =head1 CONFIGURATION FILE FORMAT
  240. The configuration options are specified in the B<req> section of
  241. the configuration file. As with all configuration files if no
  242. value is specified in the specific section (i.e. B<req>) then
  243. the initial unnamed or B<default> section is searched too.
  244. The options available are described in detail below.
  245. =over 4
  246. =item B<input_password output_password>
  247. The passwords for the input private key file (if present) and
  248. the output private key file (if one will be created). The
  249. command line options B<passin> and B<passout> override the
  250. configuration file values.
  251. =item B<default_bits>
  252. Specifies the default key size in bits.
  253. This option is used in conjunction with the B<-new> option to generate
  254. a new key. It can be overridden by specifying an explicit key size in
  255. the B<-newkey> option. The smallest accepted key size is 512 bits. If
  256. no key size is specified then 2048 bits is used.
  257. =item B<default_keyfile>
  258. This is the default filename to write a private key to. If not
  259. specified the key is written to standard output. This can be
  260. overridden by the B<-keyout> option.
  261. =item B<oid_file>
  262. This specifies a file containing additional B<OBJECT IDENTIFIERS>.
  263. Each line of the file should consist of the numerical form of the
  264. object identifier followed by white space then the short name followed
  265. by white space and finally the long name.
  266. =item B<oid_section>
  267. This specifies a section in the configuration file containing extra
  268. object identifiers. Each line should consist of the short name of the
  269. object identifier followed by B<=> and the numerical form. The short
  270. and long names are the same when this option is used.
  271. =item B<RANDFILE>
  272. At startup the specified file is loaded into the random number generator,
  273. and at exit 256 bytes will be written to it.
  274. It is used for private key generation.
  275. =item B<encrypt_key>
  276. If this is set to B<no> then if a private key is generated it is
  277. B<not> encrypted. This is equivalent to the B<-nodes> command line
  278. option. For compatibility B<encrypt_rsa_key> is an equivalent option.
  279. =item B<default_md>
  280. This option specifies the digest algorithm to use. Any digest supported by the
  281. OpenSSL B<dgst> command can be used. This option can be overridden on the
  282. command line. Certain signing algorithms (i.e. Ed25519 and Ed448) will ignore
  283. any digest that has been set.
  284. =item B<string_mask>
  285. This option masks out the use of certain string types in certain
  286. fields. Most users will not need to change this option.
  287. It can be set to several values B<default> which is also the default
  288. option uses PrintableStrings, T61Strings and BMPStrings if the
  289. B<pkix> value is used then only PrintableStrings and BMPStrings will
  290. be used. This follows the PKIX recommendation in RFC2459. If the
  291. B<utf8only> option is used then only UTF8Strings will be used: this
  292. is the PKIX recommendation in RFC2459 after 2003. Finally the B<nombstr>
  293. option just uses PrintableStrings and T61Strings: certain software has
  294. problems with BMPStrings and UTF8Strings: in particular Netscape.
  295. =item B<req_extensions>
  296. This specifies the configuration file section containing a list of
  297. extensions to add to the certificate request. It can be overridden
  298. by the B<-reqexts> command line switch. See the
  299. L<x509v3_config(5)> manual page for details of the
  300. extension section format.
  301. =item B<x509_extensions>
  302. This specifies the configuration file section containing a list of
  303. extensions to add to certificate generated when the B<-x509> switch
  304. is used. It can be overridden by the B<-extensions> command line switch.
  305. =item B<prompt>
  306. If set to the value B<no> this disables prompting of certificate fields
  307. and just takes values from the config file directly. It also changes the
  308. expected format of the B<distinguished_name> and B<attributes> sections.
  309. =item B<utf8>
  310. If set to the value B<yes> then field values to be interpreted as UTF8
  311. strings, by default they are interpreted as ASCII. This means that
  312. the field values, whether prompted from a terminal or obtained from a
  313. configuration file, must be valid UTF8 strings.
  314. =item B<attributes>
  315. This specifies the section containing any request attributes: its format
  316. is the same as B<distinguished_name>. Typically these may contain the
  317. challengePassword or unstructuredName types. They are currently ignored
  318. by OpenSSL's request signing utilities but some CAs might want them.
  319. =item B<distinguished_name>
  320. This specifies the section containing the distinguished name fields to
  321. prompt for when generating a certificate or certificate request. The format
  322. is described in the next section.
  323. =back
  324. =head1 DISTINGUISHED NAME AND ATTRIBUTE SECTION FORMAT
  325. There are two separate formats for the distinguished name and attribute
  326. sections. If the B<prompt> option is set to B<no> then these sections
  327. just consist of field names and values: for example,
  328. CN=My Name
  329. OU=My Organization
  330. emailAddress=someone@somewhere.org
  331. This allows external programs (e.g. GUI based) to generate a template file
  332. with all the field names and values and just pass it to B<req>. An example
  333. of this kind of configuration file is contained in the B<EXAMPLES> section.
  334. Alternatively if the B<prompt> option is absent or not set to B<no> then the
  335. file contains field prompting information. It consists of lines of the form:
  336. fieldName="prompt"
  337. fieldName_default="default field value"
  338. fieldName_min= 2
  339. fieldName_max= 4
  340. "fieldName" is the field name being used, for example commonName (or CN).
  341. The "prompt" string is used to ask the user to enter the relevant
  342. details. If the user enters nothing then the default value is used if no
  343. default value is present then the field is omitted. A field can
  344. still be omitted if a default value is present if the user just
  345. enters the '.' character.
  346. The number of characters entered must be between the fieldName_min and
  347. fieldName_max limits: there may be additional restrictions based
  348. on the field being used (for example countryName can only ever be
  349. two characters long and must fit in a PrintableString).
  350. Some fields (such as organizationName) can be used more than once
  351. in a DN. This presents a problem because configuration files will
  352. not recognize the same name occurring twice. To avoid this problem
  353. if the fieldName contains some characters followed by a full stop
  354. they will be ignored. So for example a second organizationName can
  355. be input by calling it "1.organizationName".
  356. The actual permitted field names are any object identifier short or
  357. long names. These are compiled into OpenSSL and include the usual
  358. values such as commonName, countryName, localityName, organizationName,
  359. organizationalUnitName, stateOrProvinceName. Additionally emailAddress
  360. is included as well as name, surname, givenName, initials, and dnQualifier.
  361. Additional object identifiers can be defined with the B<oid_file> or
  362. B<oid_section> options in the configuration file. Any additional fields
  363. will be treated as though they were a DirectoryString.
  364. =head1 EXAMPLES
  365. Examine and verify certificate request:
  366. openssl req -in req.pem -text -verify -noout
  367. Create a private key and then generate a certificate request from it:
  368. openssl genrsa -out key.pem 2048
  369. openssl req -new -key key.pem -out req.pem
  370. The same but just using req:
  371. openssl req -newkey rsa:2048 -keyout key.pem -out req.pem
  372. Generate a self signed root certificate:
  373. openssl req -x509 -newkey rsa:2048 -keyout key.pem -out req.pem
  374. Example of a file pointed to by the B<oid_file> option:
  375. 1.2.3.4 shortName A longer Name
  376. 1.2.3.6 otherName Other longer Name
  377. Example of a section pointed to by B<oid_section> making use of variable
  378. expansion:
  379. testoid1=1.2.3.5
  380. testoid2=${testoid1}.6
  381. Sample configuration file prompting for field values:
  382. [ req ]
  383. default_bits = 2048
  384. default_keyfile = privkey.pem
  385. distinguished_name = req_distinguished_name
  386. attributes = req_attributes
  387. req_extensions = v3_ca
  388. dirstring_type = nobmp
  389. [ req_distinguished_name ]
  390. countryName = Country Name (2 letter code)
  391. countryName_default = AU
  392. countryName_min = 2
  393. countryName_max = 2
  394. localityName = Locality Name (eg, city)
  395. organizationalUnitName = Organizational Unit Name (eg, section)
  396. commonName = Common Name (eg, YOUR name)
  397. commonName_max = 64
  398. emailAddress = Email Address
  399. emailAddress_max = 40
  400. [ req_attributes ]
  401. challengePassword = A challenge password
  402. challengePassword_min = 4
  403. challengePassword_max = 20
  404. [ v3_ca ]
  405. subjectKeyIdentifier=hash
  406. authorityKeyIdentifier=keyid:always,issuer:always
  407. basicConstraints = critical, CA:true
  408. Sample configuration containing all field values:
  409. RANDFILE = $ENV::HOME/.rnd
  410. [ req ]
  411. default_bits = 2048
  412. default_keyfile = keyfile.pem
  413. distinguished_name = req_distinguished_name
  414. attributes = req_attributes
  415. prompt = no
  416. output_password = mypass
  417. [ req_distinguished_name ]
  418. C = GB
  419. ST = Test State or Province
  420. L = Test Locality
  421. O = Organization Name
  422. OU = Organizational Unit Name
  423. CN = Common Name
  424. emailAddress = test@email.address
  425. [ req_attributes ]
  426. challengePassword = A challenge password
  427. Example of giving the most common attributes (subject and extensions)
  428. on the command line:
  429. openssl req -new -subj "/C=GB/CN=foo" \
  430. -addext "subjectAltName = DNS:foo.co.uk" \
  431. -addext "certificatePolicies = 1.2.3.4" \
  432. -newkey rsa:2048 -keyout key.pem -out req.pem
  433. =head1 NOTES
  434. The header and footer lines in the B<PEM> format are normally:
  435. -----BEGIN CERTIFICATE REQUEST-----
  436. -----END CERTIFICATE REQUEST-----
  437. some software (some versions of Netscape certificate server) instead needs:
  438. -----BEGIN NEW CERTIFICATE REQUEST-----
  439. -----END NEW CERTIFICATE REQUEST-----
  440. which is produced with the B<-newhdr> option but is otherwise compatible.
  441. Either form is accepted transparently on input.
  442. The certificate requests generated by B<Xenroll> with MSIE have extensions
  443. added. It includes the B<keyUsage> extension which determines the type of
  444. key (signature only or general purpose) and any additional OIDs entered
  445. by the script in an extendedKeyUsage extension.
  446. =head1 DIAGNOSTICS
  447. The following messages are frequently asked about:
  448. Using configuration from /some/path/openssl.cnf
  449. Unable to load config info
  450. This is followed some time later by...
  451. unable to find 'distinguished_name' in config
  452. problems making Certificate Request
  453. The first error message is the clue: it can't find the configuration
  454. file! Certain operations (like examining a certificate request) don't
  455. need a configuration file so its use isn't enforced. Generation of
  456. certificates or requests however does need a configuration file. This
  457. could be regarded as a bug.
  458. Another puzzling message is this:
  459. Attributes:
  460. a0:00
  461. this is displayed when no attributes are present and the request includes
  462. the correct empty B<SET OF> structure (the DER encoding of which is 0xa0
  463. 0x00). If you just see:
  464. Attributes:
  465. then the B<SET OF> is missing and the encoding is technically invalid (but
  466. it is tolerated). See the description of the command line option B<-asn1-kludge>
  467. for more information.
  468. =head1 BUGS
  469. OpenSSL's handling of T61Strings (aka TeletexStrings) is broken: it effectively
  470. treats them as ISO-8859-1 (Latin 1), Netscape and MSIE have similar behaviour.
  471. This can cause problems if you need characters that aren't available in
  472. PrintableStrings and you don't want to or can't use BMPStrings.
  473. As a consequence of the T61String handling the only correct way to represent
  474. accented characters in OpenSSL is to use a BMPString: unfortunately Netscape
  475. currently chokes on these. If you have to use accented characters with Netscape
  476. and MSIE then you currently need to use the invalid T61String form.
  477. The current prompting is not very friendly. It doesn't allow you to confirm what
  478. you've just entered. Other things like extensions in certificate requests are
  479. statically defined in the configuration file. Some of these: like an email
  480. address in subjectAltName should be input by the user.
  481. =head1 SEE ALSO
  482. L<x509(1)>, L<ca(1)>, L<genrsa(1)>,
  483. L<gendsa(1)>, L<config(5)>,
  484. L<x509v3_config(5)>
  485. =head1 COPYRIGHT
  486. Copyright 2000-2019 The OpenSSL Project Authors. All Rights Reserved.
  487. Licensed under the Apache License 2.0 (the "License"). You may not use
  488. this file except in compliance with the License. You can obtain a copy
  489. in the file LICENSE in the source distribution or at
  490. L<https://www.openssl.org/source/license.html>.
  491. =cut