Org.BouncyCastle.Crypto.Generators.Gost3410ParametersGenerator.procedure_A C# (CSharp) Method

		private int procedure_A(int x0, int c,  BigInteger[] pq, int size)
		{
			//Verify and perform condition: 0<x<2^16; 0<c<2^16; c - odd.
			while(x0<0 || x0>65536)
			{
				x0 = init_random.NextInt()/32768;
			}

			while((c<0 || c>65536) || (c/2==0))
			{
				c = init_random.NextInt()/32768 + 1;
			}

			BigInteger C = BigInteger.ValueOf(c);
			BigInteger constA16 = BigInteger.ValueOf(19381);

			//step1
			BigInteger[] y = new BigInteger[1]; // begin length = 1
			y[0] = BigInteger.ValueOf(x0);

			//step 2
			int[] t = new int[1]; // t - orders; begin length = 1
			t[0] = size;
			int s = 0;
			for (int i=0; t[i]>=17; i++)
			{
				// extension array t
				int[] tmp_t = new int[t.Length + 1];             ///////////////
					Array.Copy(t,0,tmp_t,0,t.Length);          //  extension
				t = new int[tmp_t.Length];                       //  array t
				Array.Copy(tmp_t, 0, t, 0, tmp_t.Length);  ///////////////

				t[i+1] = t[i]/2;
				s = i+1;
			}

			//step3
			BigInteger[] p = new BigInteger[s+1];
			p[s] = new BigInteger("8003",16); //set min prime number length 16 bit

			int m = s-1;  //step4

			for (int i=0; i<s; i++)
			{
				int rm = t[m]/16;  //step5

			step6: for(;;)
				   {
					   //step 6
					   BigInteger[] tmp_y = new BigInteger[y.Length];  ////////////////
					   Array.Copy(y,0,tmp_y,0,y.Length);         //  extension
					   y = new BigInteger[rm+1];                       //  array y
					   Array.Copy(tmp_y,0,y,0,tmp_y.Length);     ////////////////

					   for (int j=0; j<rm; j++)
					   {
						   y[j+1] = (y[j].Multiply(constA16).Add(C)).Mod(BigInteger.Two.Pow(16));
					   }

					   //step 7
					   BigInteger Ym = BigInteger.Zero;
					   for (int j=0; j<rm; j++)
					   {
						   Ym = Ym.Add(y[j].ShiftLeft(16*j));
					   }

					   y[0] = y[rm]; //step 8

					   //step 9
					   BigInteger N = BigInteger.One.ShiftLeft(t[m]-1).Divide(p[m+1]).Add(
						   Ym.ShiftLeft(t[m]-1).Divide(p[m+1].ShiftLeft(16*rm)));

					   if (N.TestBit(0))
					   {
						   N = N.Add(BigInteger.One);
					   }

					   //step 10

						for(;;)
						{
							//step 11
							BigInteger NByLastP = N.Multiply(p[m+1]);

							if (NByLastP.BitLength > t[m])
							{
								goto step6; //step 12
							}

							p[m] = NByLastP.Add(BigInteger.One);

							//step13
							if (BigInteger.Two.ModPow(NByLastP, p[m]).CompareTo(BigInteger.One) == 0
								&& BigInteger.Two.ModPow(N, p[m]).CompareTo(BigInteger.One) != 0)
							{
								break;
							}

							N = N.Add(BigInteger.Two);
						}

					   if (--m < 0)
					   {
						   pq[0] = p[0];
						   pq[1] = p[1];
						   return y[0].IntValue; //return for procedure B step 2
					   }

					   break; //step 14
				   }
			}
			return y[0].IntValue;
		}