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REQ(1)				    OpenSSL				REQ(1)



NAME
       req - PKCS#10 certificate request and certificate generating utility.

SYNOPSIS
       openssl req [-inform PEM|DER] [-outform PEM|DER] [-in filename]
       [-passin arg] [-out filename] [-passout arg] [-text] [-pubkey] [-noout]
       [-verify] [-modulus] [-new] [-rand file(s)] [-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] [-asn1-kludge]
       [-no-asn1-kludge] [-newhdr] [-extensions section] [-reqexts section]
       [-utf8] [-nameopt] [-reqopt] [-subject] [-subj arg] [-batch] [-verbose]
       [-engine id]

DESCRIPTION
       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.

COMMAND OPTIONS
       -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
	   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.

       -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.

       -subj arg
	   Replaces subject field of input request with specified data and
	   outputs modified request. The arg must be formatted as
	   /type0=value0/type1=value1/type2=..., characters may be escaped by
	   \ (backslash), no spaces are skipped.

       -rand file(s)
	   a file or files containing random data used to seed the random
	   number generator, or an EGD socket (see RAND_egd(3)).  Multiple
	   files can be specified separated by a OS-dependent character.  The
	   separator is ; for MS-Windows, , for OpenVMS, and : for all others.

       -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
	   approriate 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 neccessary 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 with (such as
	   -md5, -sha1). This overrides the digest algorithm specified in the
	   configuration file. For full list of possible digests see openssl
	   dgst -h output.

	   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).

       -config filename
	   this allows an alternative configuration file to be specified, this
	   overrides the compile time filename or any specified in the
	   OPENSSL_CONF environment variable.

       -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=..., characters may be escaped by
	   \ (backslash), no spaces are skipped.

       -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.

       -days n
	   when the -x509 option is being used this specifies the number of
	   days to certify the certificate for. 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.  It is possible to use negative serial numbers but this is
	   not recommended.

       -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.

       -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 discission of the  -certopt parameter in the x509 command.

       -asn1-kludge
	   by default the req command outputs certificate requests containing
	   no attributes in the correct PKCS#10 format. However certain CAs
	   will only accept requests containing no attributes in an invalid
	   form: this option produces this invalid format.

	   More precisely the Attributes in a PKCS#10 certificate request are
	   defined as a SET OF Attribute. They are not OPTIONAL so if no
	   attributes are present then they should be encoded as an empty SET
	   OF. The invalid form does not include the empty SET OF whereas the
	   correct form does.

	   It should be noted that very few CAs still require the use of this
	   option.

       -no-asn1-kludge
	   Reverses effect of -asn1-kludge

       -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.

CONFIGURATION FILE FORMAT
       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
	   This specifies a filename in which random number seed information
	   is placed and read from, or an EGD socket (see RAND_egd(3)).	 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. Possible values
	   include md5 sha1 mdc2. If not present then MD5 is used. This option
	   can be overridden on the command line.

       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.

DISTINGUISHED NAME AND ATTRIBUTE SECTION FORMAT
       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 include 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.

EXAMPLES
       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
	x509_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 = 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

NOTES
       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.

DIAGNOSTICS
       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.

ENVIRONMENT VARIABLES
       The variable OPENSSL_CONF if defined allows an alternative
       configuration file location to be specified, it will be overridden by
       the -config command line switch if it is present. For compatibility
       reasons the SSLEAY_CONF environment variable serves the same purpose
       but its use is discouraged.

BUGS
       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.

SEE ALSO
       x509(1), ca(1), genrsa(1), gendsa(1), config(5), x509v3_config(5)



1.0.2k				  2023-11-15				REQ(1)