ECCurve.F2m (iText-4.2.0 -- we had to fork it! 4.2.0-pds-1 API)

java.lang.Object
- old.org.bouncycastle.math.ec.ECCurve
- - old.org.bouncycastle.math.ec.ECCurve.F2m

Enclosing class:

ECCurve
```
public static class ECCurve.F2m
extends ECCurve
```
Elliptic curves over F2m. The Weierstrass equation is given by y² + xy = x³ + ax² + b.

Nested Class Summary
- Nested classes/interfaces inherited from class old.org.bouncycastle.math.ec.ECCurve
  ECCurve.F2m, ECCurve.Fp

Constructor Summary

Constructors
Constructor and Description
`F2m(int m, int k, BigInteger a, BigInteger b)` Constructor for Trinomial Polynomial Basis (TPB).
`F2m(int m, int k, BigInteger a, BigInteger b, BigInteger n, BigInteger h)` Constructor for Trinomial Polynomial Basis (TPB).
`F2m(int m, int k1, int k2, int k3, BigInteger a, BigInteger b)` Constructor for Pentanomial Polynomial Basis (PPB).
`F2m(int m, int k1, int k2, int k3, BigInteger a, BigInteger b, BigInteger n, BigInteger h)` Constructor for Pentanomial Polynomial Basis (PPB).

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`ECPoint`	`createPoint(BigInteger x, BigInteger y, boolean withCompression)`
`ECPoint`	`decodePoint(byte[] encoded)`
`boolean`	`equals(Object anObject)`
`ECFieldElement`	`fromBigInteger(BigInteger x)`
`int`	`getFieldSize()`
`BigInteger`	`getH()`
`ECPoint`	`getInfinity()`
`int`	`getK1()`
`int`	`getK2()`
`int`	`getK3()`
`int`	`getM()`
`BigInteger`	`getN()`
`int`	`hashCode()`
`boolean`	`isKoblitz()` Returns true if this is a Koblitz curve (ABC curve).
`boolean`	`isTrinomial()` Return true if curve uses a Trinomial basis.

Methods inherited from class old.org.bouncycastle.math.ec.ECCurve
getA, getB

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - F2m
```
public F2m(int m,
           int k,
           BigInteger a,
           BigInteger b)
```
    Constructor for Trinomial Polynomial Basis (TPB).
    
    Parameters:
    
    m - The exponent m of F_2^m.
    
    k - The integer k where x^m + x^k + 1 represents the reduction polynomial f(z).
    
    a - The coefficient a in the Weierstrass equation for non-supersingular elliptic curves over F_2^m.
    
    b - The coefficient b in the Weierstrass equation for non-supersingular elliptic curves over F_2^m.
  - F2m
```
public F2m(int m,
           int k,
           BigInteger a,
           BigInteger b,
           BigInteger n,
           BigInteger h)
```
    Constructor for Trinomial Polynomial Basis (TPB).
    
    Parameters:
    
    m - The exponent m of F_2^m.
    
    k - The integer k where x^m + x^k + 1 represents the reduction polynomial f(z).
    
    a - The coefficient a in the Weierstrass equation for non-supersingular elliptic curves over F_2^m.
    
    b - The coefficient b in the Weierstrass equation for non-supersingular elliptic curves over F_2^m.
    
    n - The order of the main subgroup of the elliptic curve.
    
    h - The cofactor of the elliptic curve, i.e. #E_a(F_2^m) = h * n.
  - F2m
```
public F2m(int m,
           int k1,
           int k2,
           int k3,
           BigInteger a,
           BigInteger b)
```
    Constructor for Pentanomial Polynomial Basis (PPB).
    
    Parameters:
    
    m - The exponent m of F_2^m.
    
    k1 - The integer k1 where x^m + x^k3 + x^k2 + x^k1 + 1 represents the reduction polynomial f(z).
    
    k2 - The integer k2 where x^m + x^k3 + x^k2 + x^k1 + 1 represents the reduction polynomial f(z).
    
    k3 - The integer k3 where x^m + x^k3 + x^k2 + x^k1 + 1 represents the reduction polynomial f(z).
    
    a - The coefficient a in the Weierstrass equation for non-supersingular elliptic curves over F_2^m.
    
    b - The coefficient b in the Weierstrass equation for non-supersingular elliptic curves over F_2^m.
  - F2m
```
public F2m(int m,
           int k1,
           int k2,
           int k3,
           BigInteger a,
           BigInteger b,
           BigInteger n,
           BigInteger h)
```
    Constructor for Pentanomial Polynomial Basis (PPB).
    
    Parameters:
    
    m - The exponent m of F_2^m.
    
    k1 - The integer k1 where x^m + x^k3 + x^k2 + x^k1 + 1 represents the reduction polynomial f(z).
    
    k2 - The integer k2 where x^m + x^k3 + x^k2 + x^k1 + 1 represents the reduction polynomial f(z).
    
    k3 - The integer k3 where x^m + x^k3 + x^k2 + x^k1 + 1 represents the reduction polynomial f(z).
    
    a - The coefficient a in the Weierstrass equation for non-supersingular elliptic curves over F_2^m.
    
    b - The coefficient b in the Weierstrass equation for non-supersingular elliptic curves over F_2^m.
    
    n - The order of the main subgroup of the elliptic curve.
    
    h - The cofactor of the elliptic curve, i.e. #E_a(F_2^m) = h * n.
- Method Detail
  - getFieldSize
```
public int getFieldSize()
```
    Specified by:
    
    getFieldSize in class ECCurve
  - fromBigInteger
```
public ECFieldElement fromBigInteger(BigInteger x)
```
    Specified by:
    
    fromBigInteger in class ECCurve
  - createPoint
```
public ECPoint createPoint(BigInteger x,
                           BigInteger y,
                           boolean withCompression)
```
    Specified by:
    
    createPoint in class ECCurve
  - decodePoint
```
public ECPoint decodePoint(byte[] encoded)
```
    Specified by:
    
    decodePoint in class ECCurve
  - getInfinity
```
public ECPoint getInfinity()
```
    Specified by:
    
    getInfinity in class ECCurve
  - isKoblitz
```
public boolean isKoblitz()
```
    Returns true if this is a Koblitz curve (ABC curve).
    
    Returns:
    
    true if this is a Koblitz curve (ABC curve), false otherwise
  - equals
```
public boolean equals(Object anObject)
```
    Overrides:
    
    equals in class Object
  - hashCode
```
public int hashCode()
```
    Overrides:
    
    hashCode in class Object
  - getM
```
public int getM()
```
  - isTrinomial
```
public boolean isTrinomial()
```
    Return true if curve uses a Trinomial basis.
    
    Returns:
    
    true if curve Trinomial, false otherwise.
  - getK1
```
public int getK1()
```
  - getK2
```
public int getK2()
```
  - getK3
```
public int getK3()
```
  - getN
```
public BigInteger getN()
```
  - getH
```
public BigInteger getH()
```

Class ECCurve.F2m

Nested Class Summary

Nested classes/interfaces inherited from class old.org.bouncycastle.math.ec.ECCurve

Constructor Summary

Method Summary

Methods inherited from class old.org.bouncycastle.math.ec.ECCurve

Methods inherited from class java.lang.Object

Constructor Detail

F2m

F2m

F2m

F2m

Method Detail

getFieldSize

fromBigInteger

createPoint

decodePoint

getInfinity

isKoblitz

equals

hashCode

getM

isTrinomial

getK1

getK2

getK3

getN

getH