com.tencent.kona.sun.security.util.math

Interface IntegerFieldModuloP

All Known Implementing Classes:

Curve25519OrderField, Curve448OrderField, IntegerPolynomial, IntegerPolynomial25519, IntegerPolynomial448, IntegerPolynomialModBinP, IntegerPolynomialModBinP.Curve25519OrderField, IntegerPolynomialModBinP.Curve448OrderField, IntegerPolynomialP256, IntegerPolynomialP384, IntegerPolynomialP521, IntegerPolynomialSM2, P256OrderField, P384OrderField, P521OrderField, SM2OrderField

public interface IntegerFieldModuloP

An interface for the field of integers modulo a prime number. An implementation of this interface can be used to get properties of the field and to produce field elements of type ImmutableIntegerModuloP from other objects and representations of field elements.

Method Summary

Modifier and Type	Method and Description
ImmutableIntegerModuloP	get0() Get the additive identity element 0
ImmutableIntegerModuloP	get1() Get the multiplicative identity element 1
ImmutableIntegerModuloP	getElement(java.math.BigInteger v) Get the field element equivalent to the supplied BigInteger value.
default ImmutableIntegerModuloP	getElement(byte[] v) Get a field element from a little-endian unsigned integer stored in an array.
ImmutableIntegerModuloP	getElement(byte[] v, int offset, int length, byte highByte) Get a field element from a little-endian unsigned integer stored at the specified position in an array.
java.math.BigInteger	getSize() Get the size of the field as a BigInteger.
SmallValue	getSmallValue(int v) Get a "small" value according to this implementation.

Method Detail

getSize

java.math.BigInteger getSize()

Get the size of the field as a BigInteger. This size is equal to the prime modulus used to construct the field.

Returns:

the size of the field.

get0

ImmutableIntegerModuloP get0()

Get the additive identity element 0

Returns:

the additive identity element

get1

ImmutableIntegerModuloP get1()

Get the multiplicative identity element 1

Returns:

the multiplicative identity element

getElement

ImmutableIntegerModuloP getElement(java.math.BigInteger v)

Get the field element equivalent to the supplied BigInteger value. The supplied value may be negative or larger than the modulus that defines the field.

Parameters:

v - a BigInteger value

Returns:

the field element corresponding to v

getSmallValue

SmallValue getSmallValue(int v)

Get a "small" value according to this implementation. This value may be used in optimized forms of some operations to avoid unnecessary calculations. For example, multiplication is much faster when it is known that one of the numbers fits within a single limb. The definition of "small", and the range of accepted values, is implementation-specific.

Parameters:

v - the small integer value

Throws:

java.lang.IllegalArgumentException - when the value is not small

getElement

default ImmutableIntegerModuloP getElement(byte[] v)

Get a field element from a little-endian unsigned integer stored in an array. The entire array will be used, and the supplied value may be larger than the modulus that defines the field. The array will not be modified.

Parameters:

v - an array containing a little-endian unsigned integer

Returns:

the field element corresponding to v

getElement

ImmutableIntegerModuloP getElement(byte[] v,
                                   int offset,
                                   int length,
                                   byte highByte)

Get a field element from a little-endian unsigned integer stored at the specified position in an array. The supplied value may be larger than the modulus that defines the field. This method also takes a byte which is interpreted as an additional high-order byte of the number. The array will not be modified.

Parameters:

v - an array containing a little-endian unsigned integer

offset - the starting position of the integer

length - the number of bytes to read

highByte - the high-order byte of the number

Returns:

the field element corresponding to the bytes at the specified position