RSA(1SSL)							      OpenSSL								 RSA(1SSL)

NAME

       openssl-rsa, rsa - RSA key processing tool

SYNOPSIS

       openssl rsa [-help] [-inform PEM|DER] [-outform PEM|DER] [-in filename] [-passin arg] [-out filename] [-passout arg] [-aes128] [-aes192]
       [-aes256] [-aria128] [-aria192] [-aria256] [-camellia128] [-camellia192] [-camellia256] [-des] [-des3] [-idea] [-text] [-noout] [-modulus]
       [-check] [-pubin] [-pubout] [-RSAPublicKey_in] [-RSAPublicKey_out] [-engine id]

DESCRIPTION

       The rsa command processes RSA keys. They can be converted between various forms and their components printed out. Note this command uses
       the traditional SSLeay compatible format for private key encryption: newer applications should use the more secure PKCS#8 format using the
       pkcs8 utility.

OPTIONS

       -help
	   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#1 RSAPrivateKey or
	   SubjectPublicKeyInfo format.  The PEM form is the default format: it consists of the DER format base64 encoded with additional header
	   and footer lines. On input PKCS#8 format private keys are 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 the PASS PHRASE ARGUMENTS section in openssl(1).

       -out filename
	   This specifies the output filename to write a key to or standard output if this option 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 password
	   The output file password source. For more information about the format of arg see the PASS PHRASE ARGUMENTS section in openssl(1).

       -aes128, -aes192, -aes256, -aria128, -aria192, -aria256, -camellia128, -camellia192, -camellia256, -des, -des3, -idea
	   These options encrypt the private key with the specified cipher 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 rsa 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 files.

       -text
	   Prints out the various public or private key components in plain text in addition to the encoded version.

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

       -modulus
	   This option prints out the value of the modulus of the key.

       -check
	   This option checks the consistency of an RSA private key.

       -pubin
	   By default a private key is read from the input file: with this option a public key is read instead.

       -pubout
	   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.

       -RSAPublicKey_in, -RSAPublicKey_out
	   Like -pubin and -pubout except RSAPublicKey format is used instead.

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

NOTES

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

	-----BEGIN RSA PRIVATE KEY-----
	-----END RSA PRIVATE KEY-----

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

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

       The PEM RSAPublicKey format uses the header and footer lines:

	-----BEGIN RSA PUBLIC KEY-----
	-----END RSA PUBLIC KEY-----

EXAMPLES

       To remove the pass phrase on an RSA private key:

	openssl rsa -in key.pem -out keyout.pem

       To encrypt a private key using triple DES:

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

       To convert a private key from PEM to DER format:

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

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

	openssl rsa -in key.pem -text -noout

       To just output the public part of a private key:

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

       Output the public part of a private key in RSAPublicKey format:

	openssl rsa -in key.pem -RSAPublicKey_out -out pubkey.pem

BUGS

       There should be an option that automatically handles .key files, without having to manually edit them.

SEE ALSO

       pkcs8(1), dsa(1), genrsa(1), gendsa(1)

COPYRIGHT

       Copyright 2000-2018 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 <https://www.openssl.org/source/license.html>.

1.1.1a								    2018-12-18								 RSA(1SSL)