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CentOS 7.0 - man page for req (centos section 1)

REQ(1)					     OpenSSL					   REQ(1)

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

       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] [-subj arg]
       [-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]

       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.

       -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

       -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).

	   prints out the certificate request in text form.

	   prints out the request subject (or certificate subject if -x509 is specified)

	   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

	   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.

       -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

       -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.

	   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 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.

	   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 0 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.

	   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 discission of the  -certopt parameter in the x509 command.

	   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.

	   Reverses effect of -asn1-kludge

	   Adds the word NEW to the PEM file header and footer lines on the outputed 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

       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.

	   This specifies the default key size in bits. If not specified then 512 is used. It is
	   used if the -new option is used. It can be overridden by using the -newkey option.

	   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.

	   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.

	   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. Possible values include md5 sha1
	   mdc2. If not present then MD5 is used. This option can be overridden on the command

	   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.

	   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

	   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

       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

	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 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_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 '.'

       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

       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, organizationUnitName, 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

       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 1024
	openssl req -new -key key.pem -out req.pem

       The same but just using req:

	openssl req -newkey rsa:1024 -keyout key.pem -out req.pem

       Generate a self signed root certificate:

	openssl req -x509 -newkey rsa:1024 -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 expansion:


       Sample configuration file prompting for field values:

	[ req ]
	default_bits	       = 1024
	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 ]

	basicConstraints = CA:true

       Sample configuration containing all field values:

	RANDFILE	       = $ENV::HOME/.rnd

	[ req ]
	default_bits	       = 1024
	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

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


       some software (some versions of Netscape certificate server) instead needs:


       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.

       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.

       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)

1.0.1e					    2014-06-17					   REQ(1)

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