init commit

output/Libraries/BouncyCastle.Crypto/Org/BouncyCastle/Bcpg/ECDHPublicBcpgKey.cs

@@ -0,0 +1,80 @@
+using System;
+using Org.BouncyCastle.Asn1;
+using Org.BouncyCastle.Math.EC;
+
+namespace Org.BouncyCastle.Bcpg;
+
+public class ECDHPublicBcpgKey : ECPublicBcpgKey
+{
+	private byte reserved;
+
+	private HashAlgorithmTag hashFunctionId;
+
+	private SymmetricKeyAlgorithmTag symAlgorithmId;
+
+	public virtual byte Reserved => reserved;
+
+	public virtual HashAlgorithmTag HashAlgorithm => hashFunctionId;
+
+	public virtual SymmetricKeyAlgorithmTag SymmetricKeyAlgorithm => symAlgorithmId;
+
+	public ECDHPublicBcpgKey(BcpgInputStream bcpgIn)
+		: base(bcpgIn)
+	{
+		int num = bcpgIn.ReadByte();
+		byte[] array = new byte[num];
+		if (array.Length != 3)
+		{
+			throw new InvalidOperationException("kdf parameters size of 3 expected.");
+		}
+		bcpgIn.ReadFully(array);
+		reserved = array[0];
+		hashFunctionId = (HashAlgorithmTag)array[1];
+		symAlgorithmId = (SymmetricKeyAlgorithmTag)array[2];
+		VerifyHashAlgorithm();
+		VerifySymmetricKeyAlgorithm();
+	}
+
+	public ECDHPublicBcpgKey(DerObjectIdentifier oid, ECPoint point, HashAlgorithmTag hashAlgorithm, SymmetricKeyAlgorithmTag symmetricKeyAlgorithm)
+		: base(oid, point)
+	{
+		reserved = 1;
+		hashFunctionId = hashAlgorithm;
+		symAlgorithmId = symmetricKeyAlgorithm;
+		VerifyHashAlgorithm();
+		VerifySymmetricKeyAlgorithm();
+	}
+
+	public override void Encode(BcpgOutputStream bcpgOut)
+	{
+		base.Encode(bcpgOut);
+		bcpgOut.WriteByte(3);
+		bcpgOut.WriteByte(reserved);
+		bcpgOut.WriteByte((byte)hashFunctionId);
+		bcpgOut.WriteByte((byte)symAlgorithmId);
+	}
+
+	private void VerifyHashAlgorithm()
+	{
+		switch (hashFunctionId)
+		{
+		case HashAlgorithmTag.Sha256:
+		case HashAlgorithmTag.Sha384:
+		case HashAlgorithmTag.Sha512:
+			return;
+		}
+		throw new InvalidOperationException("Hash algorithm must be SHA-256 or stronger.");
+	}
+
+	private void VerifySymmetricKeyAlgorithm()
+	{
+		switch (symAlgorithmId)
+		{
+		case SymmetricKeyAlgorithmTag.Aes128:
+		case SymmetricKeyAlgorithmTag.Aes192:
+		case SymmetricKeyAlgorithmTag.Aes256:
+			return;
+		}
+		throw new InvalidOperationException("Symmetric key algorithm must be AES-128 or stronger.");
+	}
+}