DHParameters
using Org.BouncyCastle.Math;
using System;
namespace Org.BouncyCastle.Crypto.Parameters
{
public class DHParameters : ICipherParameters
{
private const int DefaultMinimumLength = 160;
private readonly BigInteger p;
private readonly BigInteger g;
private readonly BigInteger q;
private readonly BigInteger j;
private readonly int m;
private readonly int l;
private readonly DHValidationParameters validation;
public BigInteger P => p;
public BigInteger G => g;
public BigInteger Q => q;
public BigInteger J => j;
public int M => m;
public int L => l;
public DHValidationParameters ValidationParameters => validation;
private static int GetDefaultMParam(int lParam)
{
if (lParam == 0)
return 160;
return System.Math.Min(lParam, 160);
}
public DHParameters(BigInteger p, BigInteger g)
: this(p, g, null, 0)
{
}
public DHParameters(BigInteger p, BigInteger g, BigInteger q)
: this(p, g, q, 0)
{
}
public DHParameters(BigInteger p, BigInteger g, BigInteger q, int l)
: this(p, g, q, GetDefaultMParam(l), l, null, null)
{
}
public DHParameters(BigInteger p, BigInteger g, BigInteger q, int m, int l)
: this(p, g, q, m, l, null, null)
{
}
public DHParameters(BigInteger p, BigInteger g, BigInteger q, BigInteger j, DHValidationParameters validation)
: this(p, g, q, 160, 0, j, validation)
{
}
public DHParameters(BigInteger p, BigInteger g, BigInteger q, int m, int l, BigInteger j, DHValidationParameters validation)
{
if (p == null)
throw new ArgumentNullException("p");
if (g == null)
throw new ArgumentNullException("g");
if (!p.TestBit(0))
throw new ArgumentException("field must be an odd prime", "p");
if (g.CompareTo(BigInteger.Two) < 0 || g.CompareTo(p.Subtract(BigInteger.Two)) > 0)
throw new ArgumentException("generator must in the range [2, p - 2]", "g");
if (q != null && q.BitLength >= p.BitLength)
throw new ArgumentException("q too big to be a factor of (p-1)", "q");
if (m >= p.BitLength)
throw new ArgumentException("m value must be < bitlength of p", "m");
if (l != 0) {
if (l >= p.BitLength)
throw new ArgumentException("when l value specified, it must be less than bitlength(p)", "l");
if (l < m)
throw new ArgumentException("when l value specified, it may not be less than m value", "l");
}
if (j != null && j.CompareTo(BigInteger.Two) < 0)
throw new ArgumentException("subgroup factor must be >= 2", "j");
this.p = p;
this.g = g;
this.q = q;
this.m = m;
this.l = l;
this.j = j;
this.validation = validation;
}
public override bool Equals(object obj)
{
if (obj == this)
return true;
DHParameters dHParameters = obj as DHParameters;
if (dHParameters == null)
return false;
return Equals(dHParameters);
}
protected virtual bool Equals(DHParameters other)
{
if (p.Equals(other.p) && g.Equals(other.g))
return object.Equals(q, other.q);
return false;
}
public override int GetHashCode()
{
int num = p.GetHashCode() ^ g.GetHashCode();
if (q != null)
num ^= q.GetHashCode();
return num;
}
}
}