public static AuthKey Deserialize(Bytes key) =>
key.ToArrayUnsafe().Apply(Helpers.Sha1).Apply(BtHelpers.Deserialize(br => {
var auxHash = br.ReadUInt64();
br.ReadBytes(4);
var keyId = br.ReadUInt64();
return(new AuthKey(key, keyId, auxHash));
}));
public static Message ReadMsg(BinaryReader br)
{
var id = br.ReadInt64();
var seqNo = br.ReadInt32();
var bodyLength = br.ReadInt32();
var body = br.ReadBytes(bodyLength);
return(new Message(id, seqNo, body.Apply(BtHelpers.Deserialize(identity))));
}
static async Task <Option <Session> > Read(string fileName)
{
if (!File.Exists(fileName))
{
return(None);
}
var bts = await FileHelpers.ReadFileBytes(fileName);
return(bts.Apply(BtHelpers.Deserialize(Session.Deserialize)));
}
public async Task <BinaryReader> Receive()
{
var plainText = await ReceivePlainText();
return(plainText.Apply(BtHelpers.Deserialize(br =>
{
var remoteSalt = br.ReadUInt64();
var remoteSessionId = br.ReadUInt64();
return br;
})));
}
async Task <byte[]> ReceivePlainText()
{
var body = await _transport.Receive();
return(body.Apply(BtHelpers.Deserialize(br =>
{
var authKeyId = br.ReadUInt64(); // TODO: check auth key id
var msgKey = br.ReadBytes(16); // TODO: check msg_key correctness
var keyData = CalcAesKey(_session.Get().AuthKey.Key.ToArrayUnsafe(), msgKey, false);
var bs = br.BaseStream;
var cipherTextLen = (int)(bs.Length - bs.Position);
var cipherText = br.ReadBytes(cipherTextLen);
var plainText = Aes.DecryptAES(keyData, cipherText);
return plainText;
})));
}