上海虹口龙之梦项目
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#if !BESTHTTP_DISABLE_ALTERNATE_SSL && (!UNITY_WEBGL || UNITY_EDITOR)
#pragma warning disable
using System;
using BestHTTP.SecureProtocol.Org.BouncyCastle.Math;
using BestHTTP.SecureProtocol.Org.BouncyCastle.Math.EC;
using BestHTTP.SecureProtocol.Org.BouncyCastle.Security;
using BestHTTP.SecureProtocol.Org.BouncyCastle.Crypto;
using BestHTTP.SecureProtocol.Org.BouncyCastle.Crypto.Parameters;
namespace BestHTTP.SecureProtocol.Org.BouncyCastle.Crypto.Agreement
{
/**
* P1363 7.2.2 ECSVDP-DHC
*
* ECSVDP-DHC is Elliptic Curve Secret Value Derivation Primitive,
* Diffie-Hellman version with cofactor multiplication. It is based on
* the work of [DH76], [Mil86], [Kob87], [LMQ98] and [Kal98a]. This
* primitive derives a shared secret value from one party's private key
* and another party's public key, where both have the same set of EC
* domain parameters. If two parties correctly execute this primitive,
* they will produce the same output. This primitive can be invoked by a
* scheme to derive a shared secret key; specifically, it may be used
* with the schemes ECKAS-DH1 and DL/ECKAS-DH2. It does not assume the
* validity of the input public key (see also Section 7.2.1).
* <p>
* Note: As stated P1363 compatibility mode with ECDH can be preset, and
* in this case the implementation doesn't have a ECDH compatibility mode
* (if you want that just use ECDHBasicAgreement and note they both implement
* BasicAgreement!).</p>
*/
public class ECDHCBasicAgreement
: IBasicAgreement
{
private ECPrivateKeyParameters privKey;
public virtual void Init(
ICipherParameters parameters)
{
if (parameters is ParametersWithRandom)
{
parameters = ((ParametersWithRandom) parameters).Parameters;
}
this.privKey = (ECPrivateKeyParameters)parameters;
}
public virtual int GetFieldSize()
{
return (privKey.Parameters.Curve.FieldSize + 7) / 8;
}
public virtual BigInteger CalculateAgreement(
ICipherParameters pubKey)
{
ECPublicKeyParameters pub = (ECPublicKeyParameters)pubKey;
ECDomainParameters dp = privKey.Parameters;
if (!dp.Equals(pub.Parameters))
throw new InvalidOperationException("ECDHC public key has wrong domain parameters");
BigInteger hd = dp.H.Multiply(privKey.D).Mod(dp.N);
// Always perform calculations on the exact curve specified by our private key's parameters
ECPoint pubPoint = ECAlgorithms.CleanPoint(dp.Curve, pub.Q);
if (pubPoint.IsInfinity)
throw new InvalidOperationException("Infinity is not a valid public key for ECDHC");
ECPoint P = pubPoint.Multiply(hd).Normalize();
if (P.IsInfinity)
throw new InvalidOperationException("Infinity is not a valid agreement value for ECDHC");
return P.AffineXCoord.ToBigInteger();
}
}
}
#pragma warning restore
#endif