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package sun.security.util.math;
import java.math.BigInteger;
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.
/**
* 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.
*/
public interface IntegerFieldModuloP {
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.
/**
* Get the size of the field as a BigInteger. This size is equal to the
* prime modulus used to construct the field.
*
* @return the size of the field.
*/
BigInteger getSize();
Get the additive identity element 0
Returns: the additive identity element
/**
* Get the additive identity element 0
*
* @return the additive identity element
*/
ImmutableIntegerModuloP get0();
Get the multiplicative identity element 1
Returns: the multiplicative identity element
/**
* Get the multiplicative identity element 1
*
* @return the multiplicative identity element
*/
ImmutableIntegerModuloP get1();
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.
Params: - v – a BigInteger value
Returns: the field element corresponding to 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.
*
* @param v a BigInteger value
* @return the field element corresponding to v
*/
ImmutableIntegerModuloP getElement(BigInteger 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.
Params: - v – the small integer value
Throws: - IllegalArgumentException – when the value is not small
/**
* 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.
*
* @param v the small integer value
* @throws IllegalArgumentException when the value is not small
*/
SmallValue getSmallValue(int 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.
Params: - v – an array containing a little-endian unsigned integer
Returns: the field element corresponding to 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.
*
* @param v an array containing a little-endian unsigned integer
* @return the field element corresponding to v
*/
default ImmutableIntegerModuloP getElement(byte[] v) {
return getElement(v, 0, v.length, (byte) 0);
}
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.
Params: - 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
/**
* 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.
*
* @param v an array containing a little-endian unsigned integer
* @param offset the starting position of the integer
* @param length the number of bytes to read
* @param highByte the high-order byte of the number
* @return the field element corresponding to the bytes at the specified
* position
*/
ImmutableIntegerModuloP getElement(byte[] v, int offset, int length,
byte highByte);
}