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

114 lines
2.7 KiB
Text

=pod
=head1 NAME
dhparam - DH parameter manipulation and generation
=head1 SYNOPSIS
B<openssl dh>
[B<-inform DER|PEM>]
[B<-outform DER|PEM>]
[B<-in filename>]
[B<-out filename>]
[B<-noout>]
[B<-text>]
[B<-C>]
[B<-2>]
[B<-5>]
[B<-rand file(s)>]
[numbits]
=head1 DESCRIPTION
This command is used to manipulate DH parameter files.
=head1 OPTIONS
=over 4
=item B<-inform DER|PEM>
This specifies the input format. The B<DER> option uses an ASN1 DER encoded
form compatible with the PKCS#3 DHparameter structure. The PEM form is the
default format: it consists of the B<DER> format base64 encoded with
additional header and footer lines.
=item B<-outform DER|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 parameters from or standard input if
this option is not specified.
=item B<-out filename>
This specifies the output filename parameters to. Standard output is used
if this option is not present. The output filename should B<not> be the same
as the input filename.
=item B<-2>, B<-5>
The generator to use, either 2 or 5. 2 is the default. If present then the
input file is ignored and parameters are generated instead.
=item B<-rand file(s)>
a file or files containing random data used to seed the random number
generator. Multiple files can be specified separated by a OS-dependent
character. For MS-Windows, the separator is B<;>. For OpenVMS, it's
B<,>. For all others, it's B<:>.
=item B<numbits>
this option specifies that a parameter set should be generated of size
B<numbits>. It must be the last option. If not present then a value of 512
is used. If this option is present then the input file is ignored and
parameters are generated instead.
=item B<-noout>
this option inhibits the output of the encoded version of the parameters.
=item B<-text>
this option prints out the DH parameters in human readable form.
=item B<-C>
this option converts the parameters into C code. The parameters can then
be loaded by calling the B<get_dhXXX()> function.
=back
=head1 WARNINGS
The program B<dhparam> combines the functionality of the programs B<dh> and
B<gendh> in previous versions of OpenSSL and SSLeay. The B<dh> and B<gendh>
programs are retained for now but may have different purposes in future
versions of OpenSSL.
=head1 NOTES
PEM format DH parameters use the header and footer lines:
-----BEGIN DH PARAMETERS-----
-----END DH PARAMETERS-----
OpenSSL currently only supports the older PKCS#3 DH, not the newer X9.42
DH.
This program manipulates DH parameters not keys.
=head1 BUGS
There should be a way to generate and manipulate DH keys.
=head1 SEE ALSO
L<dsaparam(1)|dsaparam(1)>
=cut