Crypt::ECDSA::Curve 0.052

Crypt::ECDSA::Curve is a base class for ECC curves.

These are for use with Crypt::ECDSA, a Math::GMPz based cryptography module.

METHODS

new

Constructor. Takes the following named pair arguments:

standard => standard-curve-name

Used for named standard curves such as the NIST standard curves.
Preferentially, these are invoked by classes which inherit
from Crypt::ECDSA::Curve, such as Crypt::ECDSA::Curve::Prime,
Crypt::ECDSA::Curve::Binary, or Crypt::ECDSA::Curve::Koblitz.

See US govenment standard publications FIPS 186-2 or FIPS 186-3.

used as:

new(standard => standard curve name), where curve name is one of:

Crypt::ECDSA::Curve::Prime->new( standard =>
[ one of ECP-192, ECP-224, ECP-256, ECP-384, ECP-521 ] )

Crypt::ECDSA::Curve::Koblitz->new( standard =>
[ one of EC2N-163, EC2N-233, EC2N-283, EC2N-409, EC2N-571 ] )

Koblitz curves are a special case of binary curves, with a simpler equation.

Non-standard curve types are supported either via specifying parameters and algorithm,
or by specifying a generic "standard" via specifying in new the pair:
standard => generic_prime or standard => generic_binary.

The following are used mainly for non-standard curve types. They are
gotten from pre-defined values for named curves:

p => $p , sets curve modulus ( for prime curve over F(p) )

a => $a, sets curve param a

b => $b, sets curve param b

N => the exponent in 2**N, where 2**N is a binary curve modulus
( for binary or Koblitz curve over F(2**N) )

h => curve cofactor for the point order

r => base point G order for prime curves

n => base point G order for binary curves

G_x => $x, a base point x coordinate

G_y => $y, a base point y coordinate

irreducible => binary curve irreducible basis polynimial in binary integer
format, so that x**233 + x**74 + 1 becomes
polynomial => [ 233, 74, 0 ] and irreducible =>
0x20000000000000000000000000000000000000004000000000000000001
a
my $param = $curve->a;

Returns parameter a in the elliptic equation.
b
my $param = $curve->b;

Returns parameter b in the elliptic equation.
p
my $param = $curve->p;

returns parameter p in the equation-- this is the field modulus parameter for prime curves
order
my $param = $curve->order;

Returns the curve base point G order if known.
curve_order
my $param = $curve->curve_order;

Returns the curve order if known. This might calculate the order some day.
It does not in this version.
infinity
my $inf = $curve->infinity;

Returns a valid point at infinity for the curve.
standard
my $param = $curve->standard;

Returns the standard type of the curve, if defined for the instance.