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REQ(1)				    OpenSSL				REQ(1)

       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.

	   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-

       -passin arg
	   The input file password source. For more information	about the
	   format of arg see "Pass Phrase Options" 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 "Pass Phrase Options" in openssl(1).

	   Prints out the certificate request in text form.

	   Prints out the request subject (or certificate subject if -x509 is

	   Outputs the public key.

	   This	option prevents	output of the encoded version of the request.

	   This	option prints out the value of the modulus of the public key
	   contained in	the request.

	   Verifies the	signature on the request.

	   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

	   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.

	   If this option is specified then if a private key is	created	it
	   will	not be encrypted.

	   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

       -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.

	   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.

	   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

       -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

	   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.

	   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.

	   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.

	   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.

	   Non-interactive mode.

	   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.

	   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.

	   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.

	   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.

	   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.

	   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.

	   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.

	   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.

	   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

	   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.

	   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.

	   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.

	   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.

	   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.

	   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

       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

       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

	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

       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:	       shortName       A longer	Name	       otherName       Other longer Name

       Example of a section pointed to by oid_section making use of variable


       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	]

	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 =" \
			 -addext "certificatePolicies =" \
			 -newkey rsa:2048 -keyout key.pem -out req.pem

       The header and footer lines in the PEM format are normally:


       some software (some versions of Netscape	certificate server) instead


       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:


       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:


       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

       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 2000-2021 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

1.1.1k				  2021-03-25				REQ(1)


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