public PubKey(byte[] vch)
{
if(!IsValidSize(vch.Length))
{
throw new FormatException("Invalid public key size");
}
this.vch = vch.ToArray();
_Key = new ECKey(vch, false);
}
/// <summary>
/// Create a new Public key from byte array
/// </summary>
/// <param name="bytes">byte array</param>
/// <param name="unsafe">If false, make internal copy of bytes and does perform only a costly check for PubKey format. If true, the bytes array is used as is and only PubKey.QuickCheck is used for validating the format. </param>
public PubKey(byte[] bytes, bool @unsafe)
{
if(bytes == null)
throw new ArgumentNullException("bytes");
if(!Check(bytes, false))
{
throw new FormatException("Invalid public key");
}
if(@unsafe)
this.vch = bytes;
else
{
this.vch = bytes.ToArray();
try
{
_ECKey = new ECKey(bytes, false);
}
catch(Exception ex)
{
throw new FormatException("Invalid public key", ex);
}
}
}
public void Sign(ECKey key)
{
simpleRlpSigner.Sign(key);
}
private void SetBytes(byte[] data, int count, bool fCompressedIn)
{
vch = data.SafeSubarray(0, count);
IsCompressed = fCompressedIn;
_ECKey = new ECKey(vch, true);
}
public void ReadWrite(BitcoinStream stream)
{
stream.ReadWrite(ref vch);
if(!stream.Serializing)
{
_ECKey = new ECKey(vch, true);
}
}
public static string GetPublicAddress(string privateKey)
{
var key = new ECKey(privateKey.HexToByteArray(), true);
return key.GetPublicAddress();
}
public void ShouldGenerateECKey()
{
var ecKey = EthECKey.GenerateKey();
var key = ecKey.GetPrivateKeyAsBytes();
var regeneratedKey = new ECKey(key, true);
Assert.Equal(key.ToHex(), regeneratedKey.GetPrivateKeyAsBytes().ToHex());
Assert.Equal(ecKey.GetPublicAddress(), regeneratedKey.GetPublicAddress());
}
public void ShouldSignEncodeTransactionAndRecoverPublicAddress()
{
var privateKey = "b5b1870957d373ef0eeffecc6e4812c0fd08f554b37b233526acc331bf1544f7";
var sendersAddress = "12890d2cce102216644c59daE5baed380d84830c";
var publicKey =
"87977ddf1e8e4c3f0a4619601fc08ac5c1dcf78ee64e826a63818394754cef52457a10a599cb88afb7c5a6473b7534b8b150d38d48a11c9b515dd01434cceb08";
var key = new ECKey(privateKey.HexToByteArray(), true);
var hash = "test".ToHexUTF8().HexToByteArray();
var signature = key.Sign(hash);
Assert.True(key.Verify(hash, signature));
Assert.Equal(key.GetPubKeyNoPrefix().ToHex(), publicKey);
Assert.Equal(sendersAddress.ToLower(), key.GetPublicAddress());
}
private void SetBytes(byte[] data, int count, bool fCompressedIn)
{
vch = new byte[32];
Array.Copy(data, 0, vch, 0, count);
IsCompressed = fCompressedIn;
_ECKey = new ECKey(vch, true);
}
public void Sign(ECKey key)
{
signature = key.SignAndCalculateV(RawHash);
rlpEncoded = null;
}
public static ECKey RecoverFromSignature(int recId, ECDSASignature sig, uint256 message, bool compressed)
{
if (recId < 0)
{
throw new ArgumentException("recId should be positive");
}
if (sig.R.SignValue < 0)
{
throw new ArgumentException("r should be positive");
}
if (sig.S.SignValue < 0)
{
throw new ArgumentException("s should be positive");
}
if (message == null)
{
throw new ArgumentNullException("message");
}
var curve = ECKey.CreateCurve();
// 1.0 For j from 0 to h (h == recId here and the loop is outside this function)
// 1.1 Let x = r + jn
var n = curve.N;
var i = Org.BouncyCastle.Math.BigInteger.ValueOf((long)recId / 2);
var x = sig.R.Add(i.Multiply(n));
// 1.2. Convert the integer x to an octet string X of length mlen using the conversion routine
// specified in Section 2.3.7, where mlen = ⌈(log2 p)/8⌉ or mlen = ⌈m/8⌉.
// 1.3. Convert the octet string (16 set binary digits)||X to an elliptic curve point R using the
// conversion routine specified in Section 2.3.4. If this conversion routine outputs “invalid”, then
// do another iteration of Step 1.
//
// More concisely, what these points mean is to use X as a compressed public key.
var prime = ((FpCurve)curve.Curve).Q;
if (x.CompareTo(prime) >= 0)
{
return(null);
}
// Compressed keys require you to know an extra bit of data about the y-coord as there are two possibilities.
// So it's encoded in the recId.
ECPoint R = DecompressKey(x, (recId & 1) == 1);
// 1.4. If nR != point at infinity, then do another iteration of Step 1 (callers responsibility).
if (!R.Multiply(n).IsInfinity)
{
return(null);
}
// 1.5. Compute e from M using Steps 2 and 3 of ECDSA signature verification.
var e = new Org.BouncyCastle.Math.BigInteger(1, message.ToBytes());
// 1.6. For k from 1 to 2 do the following. (loop is outside this function via iterating recId)
// 1.6.1. Compute a candidate public key as:
// Q = mi(r) * (sR - eG)
//
// Where mi(x) is the modular multiplicative inverse. We transform this into the following:
// Q = (mi(r) * s ** R) + (mi(r) * -e ** G)
// Where -e is the modular additive inverse of e, that is z such that z + e = 0 (mod n). In the above equation
// ** is point multiplication and + is point addition (the EC group operator).
//
// We can find the additive inverse by subtracting e from zero then taking the mod. For example the additive
// inverse of 3 modulo 11 is 8 because 3 + 8 mod 11 = 0, and -3 mod 11 = 8.
var eInv = Org.BouncyCastle.Math.BigInteger.Zero.Subtract(e).Mod(n);
var rInv = sig.R.ModInverse(n);
var srInv = rInv.Multiply(sig.S).Mod(n);
var eInvrInv = rInv.Multiply(eInv).Mod(n);
var q = (FpPoint)ECAlgorithms.SumOfTwoMultiplies(curve.G, eInvrInv, R, srInv);
if (compressed)
{
q = new FpPoint(curve.Curve, q.X, q.Y, true);
}
return(new ECKey(q.GetEncoded(), false));
}
