Org.BouncyCastle.Crypto.Engines.RijndaelEngine.GenerateWorkingKey C# (CSharp) Method

		private long[][] GenerateWorkingKey(
			byte[]      key)
		{
			int         KC;
			int         t, rconpointer = 0;
			int         keyBits = key.Length * 8;
			byte[,]    tk = new byte[4,MAXKC];
			//long[,]    W = new long[MAXROUNDS+1,4];
			long[][]    W = new long[MAXROUNDS+1][];

			for (int i = 0; i < MAXROUNDS+1; i++) W[i] = new long[4];

			switch (keyBits)
			{
				case 128:
					KC = 4;
					break;
				case 160:
					KC = 5;
					break;
				case 192:
					KC = 6;
					break;
				case 224:
					KC = 7;
					break;
				case 256:
					KC = 8;
					break;
				default :
					throw new ArgumentException("Key length not 128/160/192/224/256 bits.");
			}

			if (keyBits >= blockBits)
			{
				ROUNDS = KC + 6;
			}
			else
			{
				ROUNDS = (BC / 8) + 6;
			}

			//
			// copy the key into the processing area
			//
			int index = 0;

			for (int i = 0; i < key.Length; i++)
			{
				tk[i % 4,i / 4] = key[index++];
			}

			t = 0;

			//
			// copy values into round key array
			//
			for (int j = 0; (j < KC) && (t < (ROUNDS+1)*(BC / 8)); j++, t++)
			{
				for (int i = 0; i < 4; i++)
				{
					W[t / (BC / 8)][i] |= (long)(tk[i,j] & 0xff) << ((t * 8) % BC);
				}
			}

			//
			// while not enough round key material calculated
			// calculate new values
			//
			while (t < (ROUNDS+1)*(BC/8))
			{
				for (int i = 0; i < 4; i++)
				{
					tk[i,0] ^= S[tk[(i+1)%4,KC-1] & 0xff];
				}
				tk[0,0] ^= (byte) rcon[rconpointer++];

				if (KC <= 6)
				{
					for (int j = 1; j < KC; j++)
					{
						for (int i = 0; i < 4; i++)
						{
							tk[i,j] ^= tk[i,j-1];
						}
					}
				}
				else
				{
					for (int j = 1; j < 4; j++)
					{
						for (int i = 0; i < 4; i++)
						{
							tk[i,j] ^= tk[i,j-1];
						}
					}
					for (int i = 0; i < 4; i++)
					{
						tk[i,4] ^= S[tk[i,3] & 0xff];
					}
					for (int j = 5; j < KC; j++)
					{
						for (int i = 0; i < 4; i++)
						{
							tk[i,j] ^= tk[i,j-1];
						}
					}
				}

				//
				// copy values into round key array
				//
				for (int j = 0; (j < KC) && (t < (ROUNDS+1)*(BC/8)); j++, t++)
				{
					for (int i = 0; i < 4; i++)
					{
						W[t / (BC/8)][i] |= (long)(tk[i,j] & 0xff) << ((t * 8) % (BC));
					}
				}
			}
			return W;
		}