dsaparam.pod revision 325337 
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<-inform DER|PEM>]
12[B<-outform DER|PEM>]
13[B<-in filename>]
14[B<-out filename>]
15[B<-noout>]
16[B<-text>]
17[B<-C>]
18[B<-rand file(s)>]
19[B<-genkey>]
20[B<-engine id>]
21[B<numbits>]
22
23=head1 DESCRIPTION
24
25This command is used to manipulate or generate DSA parameter files.
26
27=head1 OPTIONS
28
29=over 4
30
31=item B<-inform DER|PEM>
32
33This specifies the input format. The B<DER> option uses an ASN1 DER encoded
34form compatible with RFC2459 (PKIX) DSS-Parms that is a SEQUENCE consisting
35of p, q and g respectively. The PEM form is the default format: it consists
36of the B<DER> format base64 encoded with additional header and footer lines.
37
38=item B<-outform DER|PEM>
39
40This specifies the output format, the options have the same meaning as the 
41B<-inform> option.
42
43=item B<-in filename>
44
45This specifies the input filename to read parameters from or standard input if
46this option is not specified. If the B<numbits> parameter is included then
47this option will be ignored.
48
49=item B<-out filename>
50
51This specifies the output filename parameters to. Standard output is used
52if this option is not present. The output filename should B<not> be the same
53as the input filename.
54
55=item B<-noout>
56
57this option inhibits the output of the encoded version of the parameters.
58
59=item B<-text>
60
61this option prints out the DSA parameters in human readable form.
62
63=item B<-C>
64
65this option converts the parameters into C code. The parameters can then
66be loaded by calling the B<get_dsaXXX()> function.
67
68=item B<-genkey>
69
70this option will generate a DSA either using the specified or generated
71parameters.
72
73=item B<-rand file(s)>
74
75a file or files containing random data used to seed the random number
76generator, or an EGD socket (see L<RAND_egd(3)|RAND_egd(3)>).
77Multiple files can be specified separated by a OS-dependent character.
78The separator is B<;> for MS-Windows, B<,> for OpenVMS, and B<:> for
79all others.
80
81=item B<numbits>
82
83this option specifies that a parameter set should be generated of size
84B<numbits>. It must be the last option. If this option is included then
85the input file (if any) is ignored.
86
87=item B<-engine id>
88
89specifying an engine (by its unique B<id> string) will cause B<dsaparam>
90to attempt to obtain a functional reference to the specified engine,
91thus initialising it if needed. The engine will then be set as the default
92for all available algorithms.
93
94=back
95
96=head1 NOTES
97
98PEM format DSA parameters use the header and footer lines:
99
100 -----BEGIN DSA PARAMETERS-----
101 -----END DSA PARAMETERS-----
102
103DSA parameter generation is a slow process and as a result the same set of
104DSA parameters is often used to generate several distinct keys.
105
106=head1 SEE ALSO
107
108L<gendsa(1)|gendsa(1)>, L<dsa(1)|dsa(1)>, L<genrsa(1)|genrsa(1)>,
109L<rsa(1)|rsa(1)>
110
111=cut
112