public String decipher(List <Org.BouncyCastle.Math.BigInteger> cipher, MHPrivateKey key)
{
String decrypted = "";
Org.BouncyCastle.Math.BigInteger temp = Org.BouncyCastle.Math.BigInteger.ValueOf(0);
int tmp = 0;
Org.BouncyCastle.Math.BigInteger bits = Org.BouncyCastle.Math.BigInteger.ValueOf(0);
for (int i = 0; i < cipher.Count; i++)
{
temp = cipher.ElementAt(i);
int bitlen = temp.BitLength;
int ff = 0;
while (bitlen < (int)Math.Pow(2, ff))
{
ff++;
}
if (ff > bitlen)
{
bitlen = ff;
}
for (int j = 0; j < bitlen; j++)
{
if (temp.Mod(Org.BouncyCastle.Math.BigInteger.ValueOf(2)).CompareTo(Org.BouncyCastle.Math.BigInteger.ValueOf(1)) == 0)
{
bits = bits.Add(key.w1.Multiply(Org.BouncyCastle.Math.BigInteger.ValueOf((long)Math.Pow(2, j))));
}
temp = temp.ShiftRight(1);
}
bits = bits.Mod(key.n);
List <Org.BouncyCastle.Math.BigInteger> list = key.a;
Org.BouncyCastle.Math.BigInteger temper;
int k = key.a.Count - 1;
while (k >= 0)
{
temper = list.ElementAt(k);
if (bits.CompareTo(temper) > -1)
{
tmp += (int)Math.Pow(2, k);
bits = bits.Subtract(temper);
}
k--;
}
decrypted += (binaryToChar(Convert.ToString(tmp, 2))).ToString();
bits = Org.BouncyCastle.Math.BigInteger.ValueOf(0);
tmp = 0;
}
return(decrypted);
}
public static ECPoint ECDSA_SIG_recover_key_GFp(BigInteger[] sig, byte[] hash, int recid, bool check)
{
X9ECParameters ecParams = Org.BouncyCastle.Asn1.Sec.SecNamedCurves.GetByName("secp256k1");
int i = recid / 2;
Console.WriteLine("r: "+ToHex(sig[0].ToByteArrayUnsigned()));
Console.WriteLine("s: "+ToHex(sig[1].ToByteArrayUnsigned()));
BigInteger order = ecParams.N;
BigInteger field = (ecParams.Curve as FpCurve).Q;
BigInteger x = order.Multiply(new BigInteger(i.ToString())).Add(sig[0]);
if (x.CompareTo(field) >= 0) throw new Exception("X too large");
Console.WriteLine("Order: "+ToHex(order.ToByteArrayUnsigned()));
Console.WriteLine("Field: "+ToHex(field.ToByteArrayUnsigned()));
byte[] compressedPoint = new Byte[x.ToByteArrayUnsigned().Length+1];
compressedPoint[0] = (byte) (0x02+(recid%2));
Buffer.BlockCopy(x.ToByteArrayUnsigned(), 0, compressedPoint, 1, compressedPoint.Length-1);
ECPoint R = ecParams.Curve.DecodePoint(compressedPoint);
Console.WriteLine("R: "+ToHex(R.GetEncoded()));
if (check)
{
ECPoint O = R.Multiply(order);
if (!O.IsInfinity) throw new Exception("Check failed");
}
int n = (ecParams.Curve as FpCurve).Q.ToByteArrayUnsigned().Length*8;
BigInteger e = new BigInteger(1, hash);
if (8*hash.Length > n)
{
e = e.ShiftRight(8-(n & 7));
}
e = BigInteger.Zero.Subtract(e).Mod(order);
BigInteger rr = sig[0].ModInverse(order);
BigInteger sor = sig[1].Multiply(rr).Mod(order);
BigInteger eor = e.Multiply(rr).Mod(order);
ECPoint Q = ecParams.G.Multiply(eor).Add(R.Multiply(sor));
Console.WriteLine("n: "+n);
Console.WriteLine("e: "+ToHex(e.ToByteArrayUnsigned()));
Console.WriteLine("rr: "+ToHex(rr.ToByteArrayUnsigned()));
Console.WriteLine("sor: "+ToHex(sor.ToByteArrayUnsigned()));
Console.WriteLine("eor: "+ToHex(eor.ToByteArrayUnsigned()));
Console.WriteLine("Q: "+ToHex(Q.GetEncoded()));
return Q;
}
private BigInteger BitsToInt(byte[] t)
{
BigInteger v = new BigInteger(1, t);
if (t.Length * 8 > n.BitLength)
{
v = v.ShiftRight(t.Length * 8 - n.BitLength);
}
return v;
}
private BigInteger calculateE(
BigInteger n,
byte[] message)
{
int messageBitLength = message.Length * 8;
BigInteger trunc = new BigInteger(1, message);
if (n.BitLength < messageBitLength)
{
trunc = trunc.ShiftRight(messageBitLength - n.BitLength);
}
return trunc;
}
private static IBigInteger CalculateE(IBigInteger n, byte[] message)
{
var messageBitLength = message.Length * 8;
IBigInteger trunc = new BigInteger(1, message);
if (n.BitLength < messageBitLength)
{
trunc = trunc.ShiftRight(messageBitLength - n.BitLength);
}
return trunc;
}
public void TestTestBit()
{
for (int i = 0; i < 10; ++i)
{
BigInteger n = new BigInteger(128, random);
Assert.IsFalse(n.TestBit(128));
Assert.IsTrue(n.Negate().TestBit(128));
for (int j = 0; j < 10; ++j)
{
int pos = random.Next(128);
bool test = n.ShiftRight(pos).Remainder(two).Equals(one);
Assert.AreEqual(test, n.TestBit(pos));
}
}
}
public void TestShiftRight()
{
for (int i = 0; i < 10; ++i)
{
int shift = random.Next(128);
BigInteger a = new BigInteger(256 + i, random).SetBit(256 + i);
BigInteger b = a.ShiftRight(shift);
Assert.AreEqual(a.BitLength - shift, b.BitLength);
for (int j = 0; j < b.BitLength; ++j)
{
Assert.AreEqual(a.TestBit(j + shift), b.TestBit(j));
}
}
}
public void TestGetLowestSetBit()
{
for (int i = 0; i < 10; ++i)
{
BigInteger test = new BigInteger(128, 0, random).Add(one);
int bit1 = test.GetLowestSetBit();
Assert.AreEqual(test, test.ShiftRight(bit1).ShiftLeft(bit1));
int bit2 = test.ShiftLeft(i + 1).GetLowestSetBit();
Assert.AreEqual(i + 1, bit2 - bit1);
int bit3 = test.ShiftLeft(13 * i + 1).GetLowestSetBit();
Assert.AreEqual(13 * i + 1, bit3 - bit1);
}
}
public void TestDivideAndRemainder()
{
// TODO More basic tests
BigInteger n = new BigInteger(48, random);
BigInteger[] qr = n.DivideAndRemainder(one);
Assert.AreEqual(n, qr[0]);
Assert.AreEqual(zero, qr[1]);
for (int rep = 0; rep < 10; ++rep)
{
BigInteger a = new BigInteger(100 - rep, 0, random);
BigInteger b = new BigInteger(100 + rep, 0, random);
BigInteger c = new BigInteger(10 + rep, 0, random);
BigInteger d = a.Multiply(b).Add(c);
BigInteger[] es = d.DivideAndRemainder(a);
Assert.AreEqual(b, es[0]);
Assert.AreEqual(c, es[1]);
}
// Special tests for power of two since uses different code path internally
for (int i = 0; i < 100; ++i)
{
int shift = random.Next(64);
BigInteger a = one.ShiftLeft(shift);
BigInteger b = new BigInteger(64 + random.Next(64), random);
BigInteger bShift = b.ShiftRight(shift);
BigInteger bMod = b.And(a.Subtract(one));
string data = "shift=" + shift +", b=" + b.ToString(16);
qr = b.DivideAndRemainder(a);
Assert.AreEqual(bShift, qr[0], data);
Assert.AreEqual(bMod, qr[1], data);
qr = b.DivideAndRemainder(a.Negate());
Assert.AreEqual(bShift.Negate(), qr[0], data);
Assert.AreEqual(bMod, qr[1], data);
qr = b.Negate().DivideAndRemainder(a);
Assert.AreEqual(bShift.Negate(), qr[0], data);
Assert.AreEqual(bMod.Negate(), qr[1], data);
qr = b.Negate().DivideAndRemainder(a.Negate());
Assert.AreEqual(bShift, qr[0], data);
Assert.AreEqual(bMod.Negate(), qr[1], data);
}
}
public void TestDivide()
{
for (int i = -5; i <= 5; ++i)
{
try
{
val(i).Divide(zero);
Assert.Fail("expected ArithmeticException");
}
catch (ArithmeticException) {}
}
int product = 1 * 2 * 3 * 4 * 5 * 6 * 7 * 8 * 9;
int productPlus = product + 1;
BigInteger bigProduct = val(product);
BigInteger bigProductPlus = val(productPlus);
for (int divisor = 1; divisor < 10; ++divisor)
{
// Exact division
BigInteger expected = val(product / divisor);
Assert.AreEqual(expected, bigProduct.Divide(val(divisor)));
Assert.AreEqual(expected.Negate(), bigProduct.Negate().Divide(val(divisor)));
Assert.AreEqual(expected.Negate(), bigProduct.Divide(val(divisor).Negate()));
Assert.AreEqual(expected, bigProduct.Negate().Divide(val(divisor).Negate()));
expected = val((product + 1)/divisor);
Assert.AreEqual(expected, bigProductPlus.Divide(val(divisor)));
Assert.AreEqual(expected.Negate(), bigProductPlus.Negate().Divide(val(divisor)));
Assert.AreEqual(expected.Negate(), bigProductPlus.Divide(val(divisor).Negate()));
Assert.AreEqual(expected, bigProductPlus.Negate().Divide(val(divisor).Negate()));
}
for (int rep = 0; rep < 10; ++rep)
{
BigInteger a = new BigInteger(100 - rep, 0, random);
BigInteger b = new BigInteger(100 + rep, 0, random);
BigInteger c = new BigInteger(10 + rep, 0, random);
BigInteger d = a.Multiply(b).Add(c);
BigInteger e = d.Divide(a);
Assert.AreEqual(b, e);
}
// Special tests for power of two since uses different code path internally
for (int i = 0; i < 100; ++i)
{
int shift = random.Next(64);
BigInteger a = one.ShiftLeft(shift);
BigInteger b = new BigInteger(64 + random.Next(64), random);
BigInteger bShift = b.ShiftRight(shift);
string data = "shift=" + shift +", b=" + b.ToString(16);
Assert.AreEqual(bShift, b.Divide(a), data);
Assert.AreEqual(bShift.Negate(), b.Divide(a.Negate()), data);
Assert.AreEqual(bShift.Negate(), b.Negate().Divide(a), data);
Assert.AreEqual(bShift, b.Negate().Divide(a.Negate()), data);
}
// Regression
{
int shift = 63;
BigInteger a = one.ShiftLeft(shift);
BigInteger b = new BigInteger(1, Hex.Decode("2504b470dc188499"));
BigInteger bShift = b.ShiftRight(shift);
string data = "shift=" + shift +", b=" + b.ToString(16);
Assert.AreEqual(bShift, b.Divide(a), data);
Assert.AreEqual(bShift.Negate(), b.Divide(a.Negate()), data);
// Assert.AreEqual(bShift.Negate(), b.Negate().Divide(a), data);
Assert.AreEqual(bShift, b.Negate().Divide(a.Negate()), data);
}
}
private BigInteger bits2int(byte[] @in)
{
BigInteger v = new BigInteger(1, @in);
int vlen = @in.Length * 8;
if(vlen > qlen)
{
v = v.ShiftRight(vlen - qlen);
}
return v;
}
