1=pod 2 3=head1 NAME 4 5openssl-dsaparam, 6dsaparam - DSA parameter manipulation and generation 7 8=head1 SYNOPSIS 9 10B<openssl dsaparam> 11[B<-help>] 12[B<-inform DER|PEM>] 13[B<-outform DER|PEM>] 14[B<-in filename>] 15[B<-out filename>] 16[B<-noout>] 17[B<-text>] 18[B<-C>] 19[B<-rand file...>] 20[B<-writerand file>] 21[B<-genkey>] 22[B<-engine id>] 23[B<numbits>] 24 25=head1 DESCRIPTION 26 27This command is used to manipulate or generate DSA parameter files. 28 29=head1 OPTIONS 30 31=over 4 32 33=item B<-help> 34 35Print out a usage message. 36 37=item B<-inform DER|PEM> 38 39This specifies the input format. The B<DER> option uses an ASN1 DER encoded 40form compatible with RFC2459 (PKIX) DSS-Parms that is a SEQUENCE consisting 41of p, q and g respectively. The PEM form is the default format: it consists 42of the B<DER> format base64 encoded with additional header and footer lines. 43 44=item B<-outform DER|PEM> 45 46This specifies the output format, the options have the same meaning and default 47as the B<-inform> option. 48 49=item B<-in filename> 50 51This specifies the input filename to read parameters from or standard input if 52this option is not specified. If the B<numbits> parameter is included then 53this option will be ignored. 54 55=item B<-out filename> 56 57This specifies the output filename parameters to. Standard output is used 58if this option is not present. The output filename should B<not> be the same 59as the input filename. 60 61=item B<-noout> 62 63This option inhibits the output of the encoded version of the parameters. 64 65=item B<-text> 66 67This option prints out the DSA parameters in human readable form. 68 69=item B<-C> 70 71This option converts the parameters into C code. The parameters can then 72be loaded by calling the get_dsaXXX() function. 73 74=item B<-genkey> 75 76This option will generate a DSA either using the specified or generated 77parameters. 78 79=item B<-rand file...> 80 81A file or files containing random data used to seed the random number 82generator. 83Multiple files can be specified separated by an OS-dependent character. 84The separator is B<;> for MS-Windows, B<,> for OpenVMS, and B<:> for 85all others. 86 87=item [B<-writerand file>] 88 89Writes random data to the specified I<file> upon exit. 90This can be used with a subsequent B<-rand> flag. 91 92=item B<numbits> 93 94This option specifies that a parameter set should be generated of size 95B<numbits>. It must be the last option. If this option is included then 96the input file (if any) is ignored. 97 98=item B<-engine id> 99 100Specifying an engine (by its unique B<id> string) will cause B<dsaparam> 101to attempt to obtain a functional reference to the specified engine, 102thus initialising it if needed. The engine will then be set as the default 103for all available algorithms. 104 105=back 106 107=head1 NOTES 108 109PEM format DSA parameters use the header and footer lines: 110 111 -----BEGIN DSA PARAMETERS----- 112 -----END DSA PARAMETERS----- 113 114DSA parameter generation is a slow process and as a result the same set of 115DSA parameters is often used to generate several distinct keys. 116 117=head1 SEE ALSO 118 119L<gendsa(1)>, L<dsa(1)>, L<genrsa(1)>, 120L<rsa(1)> 121 122=head1 COPYRIGHT 123 124Copyright 2000-2017 The OpenSSL Project Authors. All Rights Reserved. 125 126Licensed under the OpenSSL license (the "License"). You may not use 127this file except in compliance with the License. You can obtain a copy 128in the file LICENSE in the source distribution or at 129L<https://www.openssl.org/source/license.html>. 130 131=cut 132