openssl-req, req - PKCS#10 certificate request and certificate generating
  utility
openssl req [-help] [-inform PEM|DER] [-outform
  PEM|DER] [-in filename] [-passin arg] [-out filename]
  [-passout arg] [-text] [-pubkey] [-noout]
  [-verify] [-modulus] [-new] [-rand file...]
  [-writerand file] [-newkey rsa:bits] [-newkey alg:file]
  [-nodes] [-key filename] [-keyform PEM|DER] [-keyout
  filename] [-keygen_engine id] [-digest]
  [-config filename] [-multivalue-rdn] [-x509] [-days
  n] [-set_serial n] [-newhdr] [-addext ext]
  [-extensions section] [-reqexts section] [-precert]
  [-utf8] [-nameopt] [-reqopt] [-subject] [-subj
  arg] [-sigopt nm:v] [-batch] [-verbose] [-engine
  id]
The req command primarily creates and processes certificate requests in
  PKCS#10 format. It can additionally create self signed certificates for use as
  root CAs for example.
  - -help
- Print out a usage message.
- -inform DER|PEM
- This specifies the input format. The DER option uses an ASN1 DER
      encoded form compatible with the PKCS#10. The PEM form is the
      default format: it consists of the DER format base64 encoded with
      additional header and footer lines.
- -outform DER|PEM
- This specifies the output format, the options have the same meaning and
      default as the -inform option.
- -in filename
- This specifies the input filename to read a request from or standard input
      if this option is not specified. A request is only read if the creation
      options (-new and -newkey) are not specified.
- -sigopt nm:v
- Pass options to the signature algorithm during sign or verify operations.
      Names and values of these options are algorithm-specific.
- -passin arg
- The input file password source. For more information about the format of
      arg see the PASS PHRASE ARGUMENTS section in
      openssl(1).
- -out filename
- This specifies the output filename to write to or standard output by
      default.
- -passout arg
- The output file password source. For more information about the format of
      arg see the PASS PHRASE ARGUMENTS section in
      openssl(1).
- -text
- Prints out the certificate request in text form.
- -subject
- Prints out the request subject (or certificate subject if -x509 is
      specified)
- -pubkey
- Outputs the public key.
- -noout
- This option prevents output of the encoded version of the request.
- -modulus
- This option prints out the value of the modulus of the public key
      contained in the request.
- -verify
- Verifies the signature on the request.
- -new
- This option generates a new certificate request. It will prompt the user
      for the relevant field values. The actual fields prompted for and their
      maximum and minimum sizes are specified in the configuration file and any
      requested extensions.
    If the -key option is not used it will generate a new
        RSA private key using information specified in the configuration
      file. 
- -rand file...
- A file or files containing random data used to seed the random number
      generator. Multiple files can be specified separated by an OS-dependent
      character. The separator is ; for MS-Windows, , for OpenVMS,
      and : for all others.
- [-writerand file]
- Writes random data to the specified file upon exit. This can be
      used with a subsequent -rand flag.
- -newkey arg
- This option creates a new certificate request and a new private key. The
      argument takes one of several forms. rsa:nbits, where nbits
      is the number of bits, generates an RSA key nbits in size. If
      nbits is omitted, i.e. -newkey rsa specified, the default
      key size, specified in the configuration file is used.
    All other algorithms support the -newkey alg:file form,
        where file may be an algorithm parameter file, created by the genpkey
        -genparam command or and X.509 certificate for a key with
        appropriate algorithm. param:file generates a key using the parameter file or
        certificate file, the algorithm is determined by the parameters.
        algname:file use algorithm algname and parameter file
        file: the two algorithms must match or an error occurs.
        algname just uses algorithm algname, and parameters, if
        necessary should be specified via -pkeyopt parameter. dsa:filename generates a DSA key using the parameters
        in the file filename. ec:filename generates EC key (usable
        both with ECDSA or ECDH algorithms), gost2001:filename generates
        GOST R 34.10-2001 key (requires ccgost engine configured in the
        configuration file). If just gost2001 is specified a parameter
        set should be specified by -pkeyopt paramset:X 
- -pkeyopt opt:value
- Set the public key algorithm option opt to value. The
      precise set of options supported depends on the public key algorithm used
      and its implementation. See KEY GENERATION OPTIONS in the
      genpkey manual page for more details.
- -key filename
- This specifies the file to read the private key from. It also accepts
      PKCS#8 format private keys for PEM format files.
- -keyform PEM|DER
- The format of the private key file specified in the -key argument.
      PEM is the default.
- -keyout filename
- This gives the filename to write the newly created private key to. If this
      option is not specified then the filename present in the configuration
      file is used.
- -nodes
- If this option is specified then if a private key is created it will not
      be encrypted.
- -digest
- This specifies the message digest to sign the request. Any digest
      supported by the OpenSSL dgst command can be used. This overrides
      the digest algorithm specified in the configuration file.
    Some public key algorithms may override this choice. For
        instance, DSA signatures always use SHA1, GOST R 34.10 signatures always
        use GOST R 34.11-94 (-md_gost94), Ed25519 and Ed448 never use any
        digest. 
- -config filename
- This allows an alternative configuration file to be specified. Optional;
      for a description of the default value, see "COMMAND SUMMARY" in
      openssl(1).
- -subj arg
- Sets subject name for new request or supersedes the subject name when
      processing a request. The arg must be formatted as
      /type0=value0/type1=value1/type2=.... Keyword characters may be
      escaped by \ (backslash), and whitespace is retained. Empty values are
      permitted, but the corresponding type will not be included in the
    request.
- -multivalue-rdn
- This option causes the -subj argument to be interpreted with full support
      for multivalued RDNs. Example:
    /DC=org/DC=OpenSSL/DC=users/UID=123456+CN=John Doe If -multi-rdn is not used then the UID value is
        123456+CN=John Doe. 
- -x509
- This option outputs a self signed certificate instead of a certificate
      request. This is typically used to generate a test certificate or a self
      signed root CA. The extensions added to the certificate (if any) are
      specified in the configuration file. Unless specified using the
      set_serial option, a large random number will be used for the
      serial number.
    If existing request is specified with the -in option,
        it is converted to the self signed certificate otherwise new request is
        created. 
- -days n
- When the -x509 option is being used this specifies the number of
      days to certify the certificate for, otherwise it is ignored. n
      should be a positive integer. The default is 30 days.
- -set_serial n
- Serial number to use when outputting a self signed certificate. This may
      be specified as a decimal value or a hex value if preceded by
    0x.
- -addext ext
- Add a specific extension to the certificate (if the -x509 option is
      present) or certificate request. The argument must have the form of a
      key=value pair as it would appear in a config file.
    This option can be given multiple times. 
- -extensions section
- -reqexts section
- These options specify alternative sections to include certificate
      extensions (if the -x509 option is present) or certificate request
      extensions. This allows several different sections to be used in the same
      configuration file to specify requests for a variety of purposes.
- -precert
- A poison extension will be added to the certificate, making it a
      "pre-certificate" (see RFC6962). This can be submitted to
      Certificate Transparency logs in order to obtain signed certificate
      timestamps (SCTs). These SCTs can then be embedded into the
      pre-certificate as an extension, before removing the poison and signing
      the certificate.
    This implies the -new flag. 
- -utf8
- This option causes field values to be interpreted as UTF8 strings, by
      default they are interpreted as ASCII. This means that the field values,
      whether prompted from a terminal or obtained from a configuration file,
      must be valid UTF8 strings.
- -nameopt option
- Option which determines how the subject or issuer names are displayed. The
      option argument can be a single option or multiple options
      separated by commas. Alternatively the -nameopt switch may be used
      more than once to set multiple options. See the x509(1) manual page
      for details.
- -reqopt
- Customise the output format used with -text. The option
      argument can be a single option or multiple options separated by commas.
    See discussion of the -certopt parameter in the
        x509(1) command. 
- -newhdr
- Adds the word NEW to the PEM file header and footer lines on the
      outputted request. Some software (Netscape certificate server) and some
      CAs need this.
- -batch
- Non-interactive mode.
- -verbose
- Print extra details about the operations being performed.
- -engine id
- Specifying an engine (by its unique id string) will cause
      req to attempt to obtain a functional reference to the specified
      engine, thus initialising it if needed. The engine will then be set as the
      default for all available algorithms.
- -keygen_engine id
- Specifies an engine (by its unique id string) which would be used
      for key generation operations.
The configuration options are specified in the req section of the
  configuration file. As with all configuration files if no value is specified
  in the specific section (i.e. req) then the initial unnamed or
  default section is searched too.The options available are described in detail below.
  - input_password output_password
- The passwords for the input private key file (if present) and the output
      private key file (if one will be created). The command line options
      passin and passout override the configuration file
    values.
- default_bits
- Specifies the default key size in bits.
    This option is used in conjunction with the -new option
        to generate a new key. It can be overridden by specifying an explicit
        key size in the -newkey option. The smallest accepted key size is
        512 bits. If no key size is specified then 2048 bits is used. 
- default_keyfile
- This is the default filename to write a private key to. If not specified
      the key is written to standard output. This can be overridden by the
      -keyout option.
- oid_file
- This specifies a file containing additional OBJECT IDENTIFIERS.
      Each line of the file should consist of the numerical form of the object
      identifier followed by white space then the short name followed by white
      space and finally the long name.
- oid_section
- This specifies a section in the configuration file containing extra object
      identifiers. Each line should consist of the short name of the object
      identifier followed by = and the numerical form. The short and long
      names are the same when this option is used.
- RANDFILE
- At startup the specified file is loaded into the random number generator,
      and at exit 256 bytes will be written to it. It is used for private key
      generation.
- encrypt_key
- If this is set to no then if a private key is generated it is
      not encrypted. This is equivalent to the -nodes command line
      option. For compatibility encrypt_rsa_key is an equivalent
    option.
- default_md
- This option specifies the digest algorithm to use. Any digest supported by
      the OpenSSL dgst command can be used. This option can be overridden
      on the command line. Certain signing algorithms (i.e. Ed25519 and Ed448)
      will ignore any digest that has been set.
- string_mask
- This option masks out the use of certain string types in certain fields.
      Most users will not need to change this option.
    It can be set to several values default which is also
        the default option uses PrintableStrings, T61Strings and BMPStrings if
        the pkix value is used then only PrintableStrings and BMPStrings
        will be used. This follows the PKIX recommendation in RFC2459. If the
        utf8only option is used then only UTF8Strings will be used: this
        is the PKIX recommendation in RFC2459 after 2003. Finally the
        nombstr option just uses PrintableStrings and T61Strings: certain
        software has problems with BMPStrings and UTF8Strings: in particular
        Netscape. 
- req_extensions
- This specifies the configuration file section containing a list of
      extensions to add to the certificate request. It can be overridden by the
      -reqexts command line switch. See the x509v3_config(5)
      manual page for details of the extension section format.
- x509_extensions
- This specifies the configuration file section containing a list of
      extensions to add to certificate generated when the -x509 switch is
      used. It can be overridden by the -extensions command line
    switch.
- prompt
- If set to the value no this disables prompting of certificate
      fields and just takes values from the config file directly. It also
      changes the expected format of the distinguished_name and
      attributes sections.
- utf8
- If set to the value yes then field values to be interpreted as UTF8
      strings, by default they are interpreted as ASCII. This means that the
      field values, whether prompted from a terminal or obtained from a
      configuration file, must be valid UTF8 strings.
- attributes
- This specifies the section containing any request attributes: its format
      is the same as distinguished_name. Typically these may contain the
      challengePassword or unstructuredName types. They are currently ignored by
      OpenSSL's request signing utilities but some CAs might want them.
- distinguished_name
- This specifies the section containing the distinguished name fields to
      prompt for when generating a certificate or certificate request. The
      format is described in the next section.
There are two separate formats for the distinguished name and attribute
  sections. If the prompt option is set to no then these sections
  just consist of field names and values: for example,
 CN=My Name
 OU=My Organization
 emailAddress=someone@somewhere.org
This allows external programs (e.g. GUI based) to generate a
    template file with all the field names and values and just pass it to
    req. An example of this kind of configuration file is contained in
    the EXAMPLES section.
Alternatively if the prompt option is absent or not set to
    no then the file contains field prompting information. It consists of
    lines of the form:
 fieldName="prompt"
 fieldName_default="default field value"
 fieldName_min= 2
 fieldName_max= 4
"fieldName" is the field name being used, for example
    commonName (or CN). The "prompt" string is used to ask the user to
    enter the relevant details. If the user enters nothing then the default
    value is used if no default value is present then the field is omitted. A
    field can still be omitted if a default value is present if the user just
    enters the '.' character.
The number of characters entered must be between the fieldName_min
    and fieldName_max limits: there may be additional restrictions based on the
    field being used (for example countryName can only ever be two characters
    long and must fit in a PrintableString).
Some fields (such as organizationName) can be used more than once
    in a DN. This presents a problem because configuration files will not
    recognize the same name occurring twice. To avoid this problem if the
    fieldName contains some characters followed by a full stop they will be
    ignored. So for example a second organizationName can be input by calling it
    "1.organizationName".
The actual permitted field names are any object identifier short
    or long names. These are compiled into OpenSSL and include the usual values
    such as commonName, countryName, localityName, organizationName,
    organizationalUnitName, stateOrProvinceName. Additionally emailAddress is
    included as well as name, surname, givenName, initials, and dnQualifier.
Additional object identifiers can be defined with the
    oid_file or oid_section options in the configuration file. Any
    additional fields will be treated as though they were a DirectoryString.
Examine and verify certificate request:
 openssl req -in req.pem -text -verify -noout
Create a private key and then generate a certificate request from
    it:
 openssl genrsa -out key.pem 2048
 openssl req -new -key key.pem -out req.pem
The same but just using req:
 openssl req -newkey rsa:2048 -keyout key.pem -out req.pem
Generate a self signed root certificate:
 openssl req -x509 -newkey rsa:2048 -keyout key.pem -out req.pem
Example of a file pointed to by the oid_file option:
 1.2.3.4        shortName       A longer Name
 1.2.3.6        otherName       Other longer Name
Example of a section pointed to by oid_section making use
    of variable expansion:
 testoid1=1.2.3.5
 testoid2=${testoid1}.6
Sample configuration file prompting for field values:
 [ req ]
 default_bits           = 2048
 default_keyfile        = privkey.pem
 distinguished_name     = req_distinguished_name
 attributes             = req_attributes
 req_extensions         = v3_ca
 dirstring_type = nobmp
 [ req_distinguished_name ]
 countryName                    = Country Name (2 letter code)
 countryName_default            = AU
 countryName_min                = 2
 countryName_max                = 2
 localityName                   = Locality Name (eg, city)
 organizationalUnitName         = Organizational Unit Name (eg, section)
 commonName                     = Common Name (eg, YOUR name)
 commonName_max                 = 64
 emailAddress                   = Email Address
 emailAddress_max               = 40
 [ req_attributes ]
 challengePassword              = A challenge password
 challengePassword_min          = 4
 challengePassword_max          = 20
 [ v3_ca ]
 subjectKeyIdentifier=hash
 authorityKeyIdentifier=keyid:always,issuer:always
 basicConstraints = critical, CA:true
Sample configuration containing all field values:
 RANDFILE               = $ENV::HOME/.rnd
 [ req ]
 default_bits           = 2048
 default_keyfile        = keyfile.pem
 distinguished_name     = req_distinguished_name
 attributes             = req_attributes
 prompt                 = no
 output_password        = mypass
 [ req_distinguished_name ]
 C                      = GB
 ST                     = Test State or Province
 L                      = Test Locality
 O                      = Organization Name
 OU                     = Organizational Unit Name
 CN                     = Common Name
 emailAddress           = test@email.address
 [ req_attributes ]
 challengePassword              = A challenge password
Example of giving the most common attributes (subject and
    extensions) on the command line:
 openssl req -new -subj "/C=GB/CN=foo" \
                  -addext "subjectAltName = DNS:foo.co.uk" \
                  -addext "certificatePolicies = 1.2.3.4" \
                  -newkey rsa:2048 -keyout key.pem -out req.pem
The header and footer lines in the PEM format are normally:
 -----BEGIN CERTIFICATE REQUEST-----
 -----END CERTIFICATE REQUEST-----
some software (some versions of Netscape certificate server)
    instead needs:
 -----BEGIN NEW CERTIFICATE REQUEST-----
 -----END NEW CERTIFICATE REQUEST-----
which is produced with the -newhdr option but is otherwise
    compatible. Either form is accepted transparently on input.
The certificate requests generated by Xenroll with MSIE
    have extensions added. It includes the keyUsage extension which
    determines the type of key (signature only or general purpose) and any
    additional OIDs entered by the script in an extendedKeyUsage extension.
The following messages are frequently asked about:
        Using configuration from /some/path/openssl.cnf
        Unable to load config info
This is followed some time later by...
        unable to find 'distinguished_name' in config
        problems making Certificate Request
The first error message is the clue: it can't find the
    configuration file! Certain operations (like examining a certificate
    request) don't need a configuration file so its use isn't enforced.
    Generation of certificates or requests however does need a configuration
    file. This could be regarded as a bug.
Another puzzling message is this:
        Attributes:
            a0:00
this is displayed when no attributes are present and the request
    includes the correct empty SET OF structure (the DER encoding of
    which is 0xa0 0x00). If you just see:
        Attributes:
then the SET OF is missing and the encoding is technically
    invalid (but it is tolerated). See the description of the command line
    option -asn1-kludge for more information.
OpenSSL's handling of T61Strings (aka TeletexStrings) is broken: it effectively
  treats them as ISO-8859-1 (Latin 1), Netscape and MSIE have similar behaviour.
  This can cause problems if you need characters that aren't available in
  PrintableStrings and you don't want to or can't use BMPStrings.
As a consequence of the T61String handling the only correct way to
    represent accented characters in OpenSSL is to use a BMPString:
    unfortunately Netscape currently chokes on these. If you have to use
    accented characters with Netscape and MSIE then you currently need to use
    the invalid T61String form.
The current prompting is not very friendly. It doesn't allow you
    to confirm what you've just entered. Other things like extensions in
    certificate requests are statically defined in the configuration file. Some
    of these: like an email address in subjectAltName should be input by the
    user.
x509(1), ca(1), genrsa(1), gendsa(1),
  config(5), x509v3_config(5)
Copyright 2000-2019 The OpenSSL Project Authors. All Rights Reserved.
Licensed under the OpenSSL license (the "License"). You
    may not use this file except in compliance with the License. You can obtain
    a copy in the file LICENSE in the source distribution or at
    <https://www.openssl.org/source/license.html>.