public static SqlBoolean verifySignature(SqlString keySize, SqlString PublicKey, SqlString message, SqlString signature)
{
byte[] messageBytes = Encoding.ASCII.GetBytes(message.ToString());
byte[] signatureBytes = Convert.FromBase64String(signature.ToString());
X9ECParameters ecParams = NistNamedCurves.GetByName("P-" + keySize.ToString());
ECDomainParameters domainParameters = new ECDomainParameters(ecParams.Curve, ecParams.G, ecParams.N, ecParams.H, ecParams.GetSeed());
var G = ecParams.G;
Org.BouncyCastle.Math.EC.ECCurve curve = ecParams.Curve;
byte[] encoded = Convert.FromBase64String(PublicKey.ToString());
ECPoint q = curve.DecodePoint(encoded);
try
{
ECPublicKeyParameters pubkeyParam = new ECPublicKeyParameters(q, domainParameters);
var verifier = SignerUtilities.GetSigner("ECDSA");
verifier.Init(false, pubkeyParam);
verifier.BlockUpdate(messageBytes, 0, messageBytes.Length);
bool signatureOK = verifier.VerifySignature(signatureBytes);
return(signatureOK);
}
catch
{
return(false);
}
}
public static ECPoint CleanPoint(ECCurve c, ECPoint p)
{
ECCurve cp = p.Curve;
if (!c.Equals(cp))
{
throw new ArgumentException("Point must be on the same curve", "p");
}
return(c.DecodePoint(p.GetEncoded(false)));
}
public X9ECPoint(
ECCurve c,
Asn1OctetString s)
{
this.p = c.DecodePoint(s.GetOctets());
}
public static ECPoint DeserializeECPoint(byte[] ecPointFormats, ECCurve curve, byte[] encoding)
{
if (encoding == null || encoding.Length < 1)
throw new TlsFatalAlert(AlertDescription.illegal_parameter);
byte actualFormat;
switch (encoding[0])
{
case 0x02: // compressed
case 0x03: // compressed
{
if (ECAlgorithms.IsF2mCurve(curve))
{
actualFormat = ECPointFormat.ansiX962_compressed_char2;
}
else if (ECAlgorithms.IsFpCurve(curve))
{
actualFormat = ECPointFormat.ansiX962_compressed_prime;
}
else
{
throw new TlsFatalAlert(AlertDescription.illegal_parameter);
}
break;
}
case 0x04: // uncompressed
{
actualFormat = ECPointFormat.uncompressed;
break;
}
case 0x00: // infinity
case 0x06: // hybrid
case 0x07: // hybrid
default:
throw new TlsFatalAlert(AlertDescription.illegal_parameter);
}
if (actualFormat != ECPointFormat.uncompressed
&& (ecPointFormats == null || !Arrays.Contains(ecPointFormats, actualFormat)))
{
throw new TlsFatalAlert(AlertDescription.illegal_parameter);
}
return curve.DecodePoint(encoding);
}