openssl dsaparam

DSA parameter manipulation and generation 

openssl command

SYNOPSIS

openssl dsaparam [-inform DER|PEM] [-outform DER|PEM] [-in filename] [-out filename] [-noout] [-text] [-C] [-rand file(s)] [-genkey] [numbits]

DESCRIPTION

This command is used to manipulate or generate DSA parameter files.

Options

-inform DER|PEM 

specifies the input format. The DER option uses an ASN1 DER encoded form compatible with RFC2459 (PKIX) DSS-Parms that is a SEQUENCE consisting of p, q and g respectively. The PEM form is the default format: it consists of the DER format base64 encoded with additional header and footer lines.

-outform DER|PEM 

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

-in filename 

specifies the input file name to read parameters from or standard input if this option is not specified. If the numbits parameter is included then this option will be ignored.

-out filename 

specifies the output file name parameters to. Standard output is used if this option is not present. The output file name should not be the same as the input file name.

-noout 

inhibits the output of the encoded version of the parameters.

-text 

prints out the DSA parameters in human readable form.

-C 

converts the parameters into C code. The parameters can then be loaded by calling the get_dsaXXX() function.

-genkey 

generates a DSA either using the specified or generated parameters.

-rand file(s) 

specifies a file or files containing random data used to seed the random number generator, or an EGD socket. Multiple files can be specified separated by a OS-dependent character. The separator is ; for MS-Windows, , for OpenVMS, and : for all others.

numbits 

this option specifies that a parameter set should be generated of size numbits. It must be the last option. If this option is included then the input file (if any) is ignored.

NOTES

PEM format DSA parameters use the header and footer lines: 

 -----BEGIN DSA PARAMETERS-----
 -----END DSA PARAMETERS-----

DSA parameter generation is a slow process and as a result the same set of DSA parameters is often used to generate several distinct keys.

AVAILABILITY

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

SEE ALSO

Commands:
openssl dsa, openssl gendsa, openssl genrsa, openssl rsa