openssl/doc/apps/rsa.pod
2000-01-27 01:25:31 +00:00

161 lines
4.2 KiB
Text

=pod
=head1 NAME
rsa - RSA key processing tool
=head1 SYNOPSIS
B<openssl> B<rsa>
[B<-inform PEM|NET|DER>]
[B<-outform PEM|NET|DER>]
[B<-in filename>]
[B<-passin password>]
[B<-envpassin var>]
[B<-out filename>]
[B<-passout password>]
[B<-envpassout var>]
[B<-des>]
[B<-des3>]
[B<-idea>]
[B<-text>]
[B<-noout>]
[B<-modulus>]
[B<-check>]
[B<-pubin>]
[B<-pubout>]
=head1 DESCRIPTION
The B<rsa> command processes RSA keys. They can be converted between various
forms and their components printed out. B<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 B<pkcs8>
utility.
=head1 COMMAND OPTIONS
=over 4
=item B<-inform DER|NET|PEM>
This specifies the input format. The B<DER> option uses an ASN1 DER encoded
form compatible with the PKCS#1 RSAPrivateKey or SubjectPublicKeyInfo format.
The B<PEM> form is the default format: it consists of the B<DER> format base64
encoded with additional header and footer lines. On input PKCS#8 format private
keys are also accepted. The B<NET> form is a format compatible with older Netscape
servers and MS IIS, this uses unsalted RC4 for its encryption. It is not very
secure and so should only be used when necessary.
=item B<-outform DER|NET|PEM>
This specifies the output format, the options have the same meaning as the
B<-inform> option.
=item B<-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.
=item B<-passin password>
the input file password. Since certain utilities like "ps" make the command line
visible this option should be used with caution.
=item B<-envpassin var>
read the input file password from the environment variable B<var>.
=item B<-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 B<not> be the same as the input
filename.
=item B<-passout password>
the output file password. Since certain utilities like "ps" make the command line
visible this option should be used with caution.
=item B<-envpassout var>
read the output file password from the environment variable B<var>.
=item B<-des|-des3|-idea>
These options encrypt the private key with the DES, triple DES, or the
IDEA ciphers respectively 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 B<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.
=item B<-text>
prints out the various public or private key components in
plain text in addition to the encoded version.
=item B<-noout>
this option prevents output of the encoded version of the key.
=item B<-modulus>
this option prints out the value of the modulus of the key.
=item B<-check>
this option checks the consistency of an RSA private key.
=item B<-pubin>
by default a private key is input file with this option a public key is input
instead.
=item B<-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.
=back
=head1 NOTES
The PEM private key format uses the header and footer lines:
-----BEGIN RSA PRIVATE KEY-----
-----END RSA PRIVATE KEY-----
=head1 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
=head1 SEE ALSO
L<pkcs8(1)|pkcs8(1)>, L<dsa(1)|dsa(1)>, L<genrsa(1)|genrsa(1)>,
L<gendsa(1)|gendsa(1)>
=cut