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ECPARAM(1)			    OpenSSL			    ECPARAM(1)

       openssl-ecparam,	ecparam	- EC parameter manipulation and	generation

       openssl ecparam [-help] [-inform	DER|PEM] [-outform DER|PEM] [-in
       filename] [-out filename] [-noout] [-text] [-C] [-check]	[-name arg]
       [-list_curves] [-conv_form arg] [-param_enc arg]	[-no_seed] [-rand
       file...]	 [-writerand file] [-genkey] [-engine id]

       This command is used to manipulate or generate EC parameter files.

	   Print out a usage message.

       -inform DER|PEM
	   This	specifies the input format. The	DER option uses	an ASN.1 DER
	   encoded form	compatible with	RFC 3279 EcpkParameters. 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 parameters	from or
	   standard input if this option is not	specified.

       -out filename
	   This	specifies the output filename parameters to. Standard output
	   is used if this option is not present. The output filename should
	   not be the same as the input	filename.

	   This	option inhibits	the output of the encoded version of the

	   This	option prints out the EC parameters in human readable form.

       -C  This	option converts	the EC parameters into C code. The parameters
	   can then be loaded by calling the get_ec_group_XXX()	function.

	   Validate the	elliptic curve parameters.

       -name arg
	   Use the EC parameters with the specified 'short' name. Use
	   -list_curves	to get a list of all currently implemented EC

	   If this options is specified	ecparam	will print out a list of all
	   currently implemented EC parameters names and exit.

	   This	specifies how the points on the	elliptic curve are converted
	   into	octet strings. Possible	values are: compressed,	uncompressed
	   (the	default	value) and hybrid. For more information	regarding the
	   point conversion forms please read the X9.62	standard.  Note	Due to
	   patent issues the compressed	option is disabled by default for
	   binary curves and can be enabled by defining	the preprocessor macro
	   OPENSSL_EC_BIN_PT_COMP at compile time.

       -param_enc arg
	   This	specifies how the elliptic curve parameters are	encoded.
	   Possible value are: named_curve, i.e. the ec	parameters are
	   specified by	an OID,	or explicit where the ec parameters are
	   explicitly given (see RFC 3279 for the definition of	the EC
	   parameters structures). The default value is	named_curve.  Note the
	   implicitlyCA	alternative, as	specified in RFC 3279, is currently
	   not implemented in OpenSSL.

	   This	option inhibits	that the 'seed'	for the	parameter generation
	   is included in the ECParameters structure (see RFC 3279).

	   This	option will generate an	EC private key using the specified

       -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.

       -engine id
	   Specifying an engine	(by its	unique id string) will cause ecparam
	   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.

       PEM format EC parameters	use the	header and footer lines:


       OpenSSL is currently not	able to	generate new groups and	therefore
       ecparam can only	create EC parameters from known	(named)	curves.

       To create EC parameters with the	group 'prime192v1':

	 openssl ecparam -out ec_param.pem -name prime192v1

       To create EC parameters with explicit parameters:

	 openssl ecparam -out ec_param.pem -name prime192v1 -param_enc explicit

       To validate given EC parameters:

	 openssl ecparam -in ec_param.pem -check

       To create EC parameters and a private key:

	 openssl ecparam -out ec_key.pem -name prime192v1 -genkey

       To change the point encoding to 'compressed':

	 openssl ecparam -in ec_in.pem -out ec_out.pem -conv_form compressed

       To print	out the	EC parameters to standard output:

	 openssl ecparam -in ec_param.pem -noout -text

       ec(1), dsaparam(1)

       Copyright 2003-2018 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			    ECPARAM(1)


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