openssl rsa

RSA key processing tool 

openssl command


SYNOPSIS

openssl rsa [-inform DER|PEM] [-outform DER|PEM] [-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 

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 

specifies the output format, the options have the same meaning and default as the -inform option.

-in filename 

specifies the input file name 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 

specifies the input file password source. For more information about the format of arg see the PASS PHRASE ARGUMENTS section in the openssl reference page.

-out filename 

specifies the output file name 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 file name should not be the same as the input file name.

-passout password 

specifies the output file password source. For more information about the format of arg see the PASS PHRASE ARGUMENTS section in the openssl reference page.

-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 

prevents output of the encoded version of the key.

-modulus 

prints out the value of the modulus of the key.

-check 

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 

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.


COPYRIGHT

Copyright 2016-2018 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 here: OpenSSL.


AVAILABILITY

PTC MKS Toolkit for System Administrators
PTC MKS Toolkit for Developers
PTC MKS Toolkit for Interoperability
PTC MKS Toolkit for Professional Developers
PTC MKS Toolkit for Professional Developers 64-Bit Edition
PTC MKS Toolkit for Enterprise Developers
PTC MKS Toolkit for Enterprise Developers 64-Bit Edition


SEE ALSO

Commands:
openssl dsa, openssl gendsa, openssl genrsa, openssl pkcs8


PTC MKS Toolkit 10.3 Documentation Build 39.