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EC(1)				    OpenSSL				 EC(1)

       openssl-ec, ec -	EC key processing

       openssl ec [-help] [-inform PEM|DER] [-outform PEM|DER] [-in filename]
       [-passin	arg] [-out filename] [-passout arg] [-des] [-des3] [-idea]
       [-text] [-noout]	[-param_out] [-pubin] [-pubout]	[-conv_form arg]
       [-param_enc arg]	[-no_public] [-check] [-engine id]

       The ec command processes	EC keys. They can be converted between various
       forms and their components printed out. Note OpenSSL uses the private
       key format specified in 'SEC 1: Elliptic	Curve Cryptography'
       ( To convert an OpenSSL EC	private	key into the
       PKCS#8 private key format use the pkcs8 command.

	   Print out a usage message.

       -inform DER|PEM
	   This	specifies the input format. The	DER option with	a private key
	   uses	an ASN.1 DER encoded SEC1 private key. When used with a	public
	   key it uses the SubjectPublicKeyInfo	structure as specified in RFC
	   3280.  The PEM form is the default format: it consists of the DER
	   format base64 encoded with additional header	and footer lines. In
	   the case of a private key PKCS#8 format is also accepted.

       -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 key from	or standard
	   input if this option	is not specified. If the key is	encrypted a
	   pass	phrase will be prompted	for.

       -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 a key to	or standard
	   output by is	not specified. If any encryption options are set then
	   a pass phrase will be prompted for. The output filename should not
	   be the same as the input filename.

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

	   These options encrypt the private key with the DES, triple DES,
	   IDEA	or any other cipher supported by OpenSSL before	outputting it.
	   A pass phrase is prompted for.  If none of these options is
	   specified the key is	written	in plain text. This means that using
	   the ec utility to read in an	encrypted key with no encryption
	   option can be used to remove	the pass phrase	from a key, or by
	   setting the encryption options it can be use	to add or change the
	   pass	phrase.	 These options can only	be used	with PEM format	output

	   Prints out the public, private key components and parameters.

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

	   By default, a private key is	read from the input file. With this
	   option a public key is read instead.

	   By default a	private	key is output. With this option	a public key
	   will	be output instead. This	option is automatically	set if the
	   input is a public key.

	   This	specifies how the points on the	elliptic curve are converted
	   into	octet strings. Possible	values are: compressed (the default
	   value), uncompressed	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 omits the public	key components from the	private	key

	   This	option checks the consistency of an EC private or public key.

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

       The PEM private key format uses the header and footer lines:


       The PEM public key format uses the header and footer lines:

	-----END PUBLIC	KEY-----

       To encrypt a private key	using triple DES:

	openssl	ec -in key.pem -des3 -out keyout.pem

       To convert a private key	from PEM to DER	format:

	openssl	ec -in key.pem -outform	DER -out keyout.der

       To print	out the	components of a	private	key to standard	output:

	openssl	ec -in key.pem -text -noout

       To just output the public part of a private key:

	openssl	ec -in key.pem -pubout -out pubkey.pem

       To change the parameters	encoding to explicit:

	openssl	ec -in key.pem -param_enc explicit -out	keyout.pem

       To change the point conversion form to compressed:

	openssl	ec -in key.pem -conv_form compressed -out keyout.pem

       ecparam(1), dsa(1), rsa(1)

       Copyright 2003-2021 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				 EC(1)


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