/// <summary>
/// Deserialize an object from TL serialization context.
/// </summary>
/// <remarks>
/// Constructor number for the object is automatically determined by reading the first number from the streamer,
/// hence object within the context streamer must be serialized as boxed type.
/// </remarks>
/// <param name="context">TL serialization context.</param>
/// <returns>Deserialized object.</returns>
/// <exception cref="TLSerializerNotFoundException">When serializer not found.</exception>
public static object Deserialize(TLSerializationContext context)
{
// Here streamer's position must point to a boxed TL type.
TLStreamer streamer = context.Streamer;
// Read a constructor number and restore the streamer position.
streamer.PushPosition();
uint constructorNumber = streamer.ReadUInt32();
//Console.WriteLine("Retrived constructor number " + constructorNumber);
streamer.PopPosition();
ITLSerializer serializer = context.Rig.GetSerializerByConstructorNumber(constructorNumber);
//Console.WriteLine("Got serializer for above constructor number" + serializer.SupportedType);
if (serializer == null)
{
throw new TLSerializerNotFoundException(
string.Format("Constructor number: 0x{0:X8} is not supported by any registered serializer.", constructorNumber));
}
return(serializer.Read(context, TLSerializationMode.Boxed));
}
/// <summary>
/// Deserialize an object from TL serialization context.
/// </summary>
/// <remarks>
/// Constructor number for the object is automatically determined by reading the first number from the streamer,
/// hence object within the context streamer must be serialized as boxed type.
/// </remarks>
/// <param name="context">TL serialization context.</param>
/// <returns>Deserialized object.</returns>
/// <exception cref="TLSerializerNotFoundException">When serializer not found.</exception>
public static object Deserialize(TLSerializationContext context)
{
TLStreamer streamer = context.Streamer;
// Read a constructor number.
uint constructorNumber = streamer.ReadUInt32();
ITLSerializer serializer = context.Rig.GetSerializerByConstructorNumber(constructorNumber);
if (serializer == null)
{
throw new TLSerializerNotFoundException(string.Format("Constructor number: 0x{0:X8} is not supported by any registered serializer.", constructorNumber));
}
// Bare because construction number has already been read.
return(serializer.Read(context, TLSerializationMode.Bare));
}
private void InitAndCheckConsistency()
{
int length = _data.Length;
using (var streamer = new TLStreamer(_data))
{
int expectedLength = streamer.ReadInt32();
if (length != expectedLength)
{
throw new TransportException(string.Format("Invalid packet length. Expected: {0}, actual: {1}.", expectedLength, length));
}
Number = streamer.ReadInt32();
streamer.Seek(-4, SeekOrigin.End);
Crc32 = streamer.ReadUInt32();
}
uint actualCrc32 = ComputeCrc32();
if (Crc32 != actualCrc32)
{
throw new TransportException(string.Format("Invalid packet CRC32. Expected: {0}, actual: {1}.", actualCrc32, Crc32));
}
}
public IMessage DecodeEncryptedMessage(byte[] messageBytes, byte[] authKey, Sender sender, out UInt64 salt, out UInt64 sessionId)
{
Argument.IsNotNull(() => authKey);
Argument.IsNotNull(() => messageBytes);
ulong providedAuthKeyId = ComputeAuthKeyId(authKey);
var encryptedData = new byte[messageBytes.Length - EncryptedOuterHeaderLength];
Int128 msgKey;
using (var streamer = new TLStreamer(messageBytes))
{
// Reading header.
ulong authKeyId = streamer.ReadUInt64();
if (authKeyId != providedAuthKeyId)
{
throw new InvalidAuthKey(string.Format("Message encrypted with auth key with id={0}, but auth key provided for decryption with id={1}.", authKeyId,
providedAuthKeyId));
}
msgKey = streamer.ReadInt128();
// Reading encrypted data.
streamer.Read(encryptedData, 0, encryptedData.Length);
}
// Decrypting.
byte[] aesKey, aesIV;
ComputeAesKeyAndIV(authKey, msgKey, out aesKey, out aesIV, sender);
byte[] innerDataWithPadding = _encryptionServices.Aes256IgeDecrypt(encryptedData, aesKey, aesIV);
Int32 msgDataLength;
UInt64 msgId;
UInt32 seqno;
Object body;
using (var streamer = new TLStreamer(innerDataWithPadding))
{
salt = streamer.ReadUInt64();
sessionId = streamer.ReadUInt64();
msgId = streamer.ReadUInt64();
seqno = streamer.ReadUInt32();
msgDataLength = streamer.ReadInt32();
body = _tlRig.Deserialize(streamer);
}
int innerDataLength = EncryptedInnerHeaderLength + msgDataLength;
// When an encrypted message is received, it must be checked that
// msg_key is in fact equal to the 128 lower-order bits
// of the SHA1 hash of the previously encrypted portion.
Int128 expectedMsgKey = ComputeMsgKey(new ArraySegment<byte>(innerDataWithPadding, 0, innerDataLength));
if (msgKey != expectedMsgKey)
{
throw new InvalidMessageException(string.Format("Expected message key to be {0}, but actual is {1}.", expectedMsgKey, msgKey));
}
return new Message(msgId, seqno, body);
}
public override uint ReadUInt32()
{
lock (_streamer)
return(_streamer.ReadUInt32());
}