public void EncryptNoTag()
{
Encrypt0Message msg = new Encrypt0Message(false, true);
msg.AddAttribute(HeaderKeys.Algorithm, AlgorithmValues.AES_GCM_128, Attributes.PROTECTED);
msg.AddAttribute(HeaderKeys.IV, CBORObject.FromObject(rgbIV96), Attributes.PROTECTED);
msg.SetContent(rgbContent);
msg.Encrypt(rgbKey128);
CBORObject cn = msg.EncodeToCBORObject();
Assert.AreEqual(cn.IsTagged, (false));
}
public void encryptNoEmitContent()
{
Encrypt0Message msg = new Encrypt0Message(true, false);
msg.AddAttribute(HeaderKeys.Algorithm, AlgorithmValues.AES_GCM_128, Attributes.PROTECTED);
msg.AddAttribute(HeaderKeys.IV, CBORObject.FromObject(rgbIV96), Attributes.UNPROTECTED);
msg.SetContent(strContent);
msg.Encrypt(rgbKey128);
CBORObject cn = msg.EncodeToCBORObject();
Assert.IsTrue(cn[2].IsNull);
}
public void TestRoundTrip4()
{
Encrypt0Message msg = new Encrypt0Message();
msg.AddAttribute(HeaderKeys.Algorithm, AlgorithmValues.AES_GCM_128, Attributes.PROTECTED);
msg.AddAttribute(HeaderKeys.IV, CBORObject.FromObject(rgbIV96), Attributes.PROTECTED);
msg.SetContent(rgbContent);
msg.Encrypt(rgbKey128);
CBORObject rgbMsg = msg.EncodeToCBORObject();
msg = (Encrypt0Message)Message.DecodeFromCBOR(rgbMsg);
byte[] contentNew = msg.Decrypt(rgbKey128);
CollectionAssert.AreEqual(rgbContent, (contentNew));
}
private static byte[] DoCompression(Encrypt0Message msg)
{
// Start with 0abc deee
// a, b, c and d are presence flags
// eee is the length of the iv field.
int cbSize = 1;
//
CBORObject partialIV = msg.FindAttribute(HeaderKeys.PartialIV);
byte[] iv = new byte[0];
if (partialIV != null)
{
iv = partialIV.GetByteString();
}
cbSize += iv.Length;
byte head = (byte)iv.Length;
// Context Hint/Group ID
CBORObject gid = msg.FindAttribute(CBORObject.FromObject("gid"));
if (gid != null)
{
cbSize += (1 + gid.GetByteString().Length);
head |= 0x10;
}
CBORObject sig = msg.FindAttribute(HeaderKeys.CounterSignature);
byte[] sigBytes = null;
if (sig != null)
{
sigBytes = sig.EncodeToBytes();
cbSize += (1 + sigBytes.Length);
head |= 0x20;
}
CBORObject kid = msg.FindAttribute(HeaderKeys.KeyId);
if (kid != null)
{
cbSize += (0 + kid.GetByteString().Length);
head |= 0x08;
}
// Additional items to flag
byte[] encBody = new byte[cbSize];
encBody[0] = head;
cbSize = 1;
if (iv.Length > 0)
{
Array.Copy(iv, 0, encBody, cbSize, iv.Length);
cbSize += iv.Length;
}
if (gid != null)
{
if (gid.GetByteString().Length > 255)
{
throw new Exception("GID too large");
}
encBody[cbSize] = (byte)gid.GetByteString().Length;
Array.Copy(gid.GetByteString(), 0, encBody, cbSize + 1, gid.GetByteString().Length);
cbSize += gid.GetByteString().Length + 1;
}
if (sig != null)
{
if (sigBytes.Length > 255)
{
throw new Exception("SIG too large");
}
encBody[cbSize] = (byte)sigBytes.Length;
Array.Copy(sigBytes, 0, encBody, cbSize + 1, sig.GetByteString().Length);
cbSize += sigBytes.Length + 1;
}
if (kid != null)
{
if (kid.GetByteString().Length > 255)
{
throw new Exception("KID too large");
}
Array.Copy(kid.GetByteString(), 0, encBody, cbSize, kid.GetByteString().Length);
}
#if DEBUG
{
CBORObject xxx = msg.EncodeToCBORObject();
Console.WriteLine("Protected Attributes = " + BitConverter.ToString(xxx[0].GetByteString()));
}
#endif
return(encBody);
}
public byte[] CreateMessage2()
{
CBORObject msg = CBORObject.NewArray();
CBORObject obj;
if (_fSymmetricSecret)
{
msg.Add(5); // Msg Type
}
else
{
msg.Add(2);
}
msg.Add(_SessionId[1]); // S_U
msg.Add(_SessionId[0]); // S_V
msg.Add(_Nonce[0]); // N_V
msg.Add(_Keys[0].PublicKey().AsCBOR()); // E_V
msg.Add(_algKeyAgree); // HKDF_V
msg.Add(_algAEAD); // AEAD_V
if (!_fSymmetricSecret)
{
msg.Add(_algSign); // SIG_V
obj = CBORObject.NewArray();
obj.Add(AlgorithmValuesInt.ECDSA_256);
obj.Add(AlgorithmValues.EdDSA);
msg.Add(obj); // SIGs_V
}
if (_algKeyAgree.Equals(COSE.AlgorithmValues.ECDH_SS_HKDF_256))
{
_MessageDigest = new Sha256Digest();
}
byte[] data2 = msg.EncodeToBytes();
byte[] aad_2 = ConcatenateAndHash(new byte[2][] { _Messages[0], data2 }, _MessageDigest); // M00TODO - hash message[0] before passing it in.
byte[][] useKeys = _DeriveKeys(_Keys, _SecretSalt, aad_2, _algAEAD);
byte[] aeadKey = useKeys[0];
byte[] signResult = new byte[0];
if (!_fSymmetricSecret)
{
Sign1Message sign1 = new Sign1Message(false, false);
sign1.SetContent(aad_2);
sign1.AddAttribute(HeaderKeys.KeyId, _SigningKey[CoseKeyKeys.KeyIdentifier], Attributes.UNPROTECTED);
sign1.AddAttribute(HeaderKeys.Algorithm, _algSign, Attributes.DO_NOT_SEND);
sign1.Sign(_SigningKey);
signResult = sign1.EncodeToBytes();
}
Encrypt0Message enc0 = new Encrypt0Message(true);
enc0.AddAttribute(HeaderKeys.Algorithm, _algAEAD, Attributes.DO_NOT_SEND);
enc0.AddAttribute(HeaderKeys.IV, CBORObject.FromObject(useKeys[1]), Attributes.DO_NOT_SEND);
enc0.SetExternalData(aad_2);
CBORObject encContent = CBORObject.NewArray();
encContent.Add(signResult);
enc0.SetContent(encContent.EncodeToBytes());
enc0.Encrypt(aeadKey);
msg.Add(enc0.EncodeToCBORObject()); // COSE_ENC_2
_Messages[1] = msg.EncodeToBytes();
_LastMessageAuthenticator = ConcatenateAndHash(new byte[][] { _Messages[0], _Messages[1] }, _MessageDigest);
return(_Messages[1]);
}
