Fix utils and create MTProtoPlainSender

lib/src/main/java/io/github/lonamiwebs/overgram/Overgram.java

@@ -1,14 +1,23 @@
 package io.github.lonamiwebs.overgram;
 
+import io.github.lonamiwebs.overgram.crypto.Authenticator;
+import io.github.lonamiwebs.overgram.network.MTProtoPlainSender;
 import io.github.lonamiwebs.overgram.network.connection.Connection;
 import io.github.lonamiwebs.overgram.network.connection.TcpFull;
+import io.github.lonamiwebs.overgram.utils.BinaryWriter;
 
 import java.io.IOException;
 
 public class Overgram {
-    public static void main(final String... args) throws IOException {
+    public static void main(final String... args) throws IOException, ClassNotFoundException {
         final Connection connection = new TcpFull();
+        try {
             connection.connect("149.154.167.91", 443);
+
+            final MTProtoPlainSender sender = new MTProtoPlainSender(connection);
+            Authenticator.doAuthentication(sender);
+        } finally {
             connection.disconnect();
         }
     }
+}

lib/src/main/java/io/github/lonamiwebs/overgram/crypto/Authenticator.java

@@ -0,0 +1,22 @@
+package io.github.lonamiwebs.overgram.crypto;
+
+import io.github.lonamiwebs.overgram.network.MTProtoPlainSender;
+import io.github.lonamiwebs.overgram.tl.Functions;
+import io.github.lonamiwebs.overgram.tl.TLObject;
+import io.github.lonamiwebs.overgram.tl.Types;
+
+import java.io.IOException;
+import java.math.BigInteger;
+import java.security.SecureRandom;
+
+public class Authenticator {
+
+    public static void doAuthentication(final MTProtoPlainSender sender) throws IOException, ClassNotFoundException {
+        final byte[] nonceBytes = new byte[16];
+        new SecureRandom().nextBytes(nonceBytes);
+        final BigInteger nonce = new BigInteger(nonceBytes);
+
+        final TLObject result = sender.send(new Functions.ReqPqMulti().nonce(nonce));
+        assert result instanceof Types.ResPQ;
+    }
+}

lib/src/main/java/io/github/lonamiwebs/overgram/network/MTProtoPlainSender.java

@@ -0,0 +1,57 @@
+package io.github.lonamiwebs.overgram.network;
+
+import io.github.lonamiwebs.overgram.network.connection.Connection;
+import io.github.lonamiwebs.overgram.tl.TLObject;
+import io.github.lonamiwebs.overgram.tl.TLRequest;
+import io.github.lonamiwebs.overgram.utils.BinaryReader;
+import io.github.lonamiwebs.overgram.utils.BinaryWriter;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+
+public class MTProtoPlainSender {
+    private final Connection connection;
+    private final MTProtoState state;
+
+    public MTProtoPlainSender(final Connection connection) {
+        this.connection = connection;
+        this.state = new MTProtoState();
+    }
+
+    public TLObject send(final TLRequest request) throws IOException, ClassNotFoundException {
+        final long msgId = state.getNewMsgId();
+
+        final BinaryWriter writer = new BinaryWriter();
+        request.serialize(writer);
+        final byte[] requestBytes = writer.toBytes();
+        writer.clear();
+
+        writer.write(0L);
+        writer.write(msgId);
+        writer.write(requestBytes.length);
+        writer.writeRaw(requestBytes);
+        connection.send(writer.toBytes());
+
+        final byte[] body = connection.recv();
+        if (body[0] == (byte) 0x6c
+                && body[1] == (byte) 0xfe
+                && body[2] == (byte) 0xff
+                && body[3] == (byte) 0xff) {
+            // -404 as little endian, broken authorization
+            throw new RuntimeException();
+        }
+
+        final BinaryReader reader = new BinaryReader(ByteBuffer.wrap(body).order(ByteOrder.LITTLE_ENDIAN));
+        final long authKeyId = reader.readLong();
+        assert authKeyId == 0;
+
+        final long serverMsgId = reader.readLong();
+        assert serverMsgId != 0;
+
+        final int length = reader.readInt();
+        assert length > 0;
+
+        return reader.readTl();
+    }
+}

lib/src/main/java/io/github/lonamiwebs/overgram/network/MTProtoState.java

@@ -0,0 +1,64 @@
+package io.github.lonamiwebs.overgram.network;
+
+import io.github.lonamiwebs.overgram.tl.TLObject;
+
+import java.security.SecureRandom;
+
+public class MTProtoState {
+
+    private final long id;
+    private long timeOffset;
+    private int sequence;
+    private long lastMsgId;
+
+    public MTProtoState() {
+        id = new SecureRandom().nextLong();
+        timeOffset = 0;
+        sequence = 0;
+        lastMsgId = 0;
+
+        // TODO auth_key, salt
+    }
+
+    public Object createMessage(final TLObject object, final long afterId) {
+        throw new UnsupportedOperationException();
+    }
+
+    public static Object calcKey(final Object authKey, final byte[] msgKey, final boolean client) {
+        throw new UnsupportedOperationException();
+    }
+
+    public byte[] packMessage(final Object message) {
+        throw new UnsupportedOperationException();
+    }
+
+    public Object unpackMessage(final byte[] body) {
+        throw new UnsupportedOperationException();
+    }
+
+    public long getNewMsgId() {
+        final long now = System.currentTimeMillis();
+        long newMsgId = (((now / 1000) + timeOffset) << 32) | ((now % 1000) << 2);
+        if (lastMsgId >= newMsgId) {
+            newMsgId = lastMsgId + 4;
+        }
+
+        lastMsgId = newMsgId;
+        return newMsgId;
+    }
+
+    public void updateTimeOffset(long correctMsgId) {
+        final long now = System.currentTimeMillis() / 1000L;
+        final long correct = correctMsgId >> 32;
+        timeOffset = correct - now;
+        lastMsgId = 0;
+    }
+
+    public int getSeqNo(final boolean contentRelated) {
+        if (contentRelated) {
+            return 1 + 2 * sequence++;
+        } else {
+            return 2 * sequence;
+        }
+    }
+}

lib/src/main/java/io/github/lonamiwebs/overgram/network/connection/TcpFull.java

@@ -31,8 +31,7 @@ public class TcpFull extends Connection {
     public void send(final byte[] data) throws IOException {
         final int length = data.length + 12;
 
-        final ByteBuffer buffer = ByteBuffer.allocate(length);
+        final ByteBuffer buffer = ByteBuffer.allocate(length).order(ByteOrder.LITTLE_ENDIAN);
-        buffer.order(ByteOrder.LITTLE_ENDIAN);
 
         buffer.putInt(length);
         buffer.putInt(counter);
@@ -48,7 +47,7 @@ public class TcpFull extends Connection {
 
     @Override
     public byte[] recv() throws IOException {
-        final ByteBuffer buffer = ByteBuffer.wrap(client.read(8));
+        final ByteBuffer buffer = ByteBuffer.wrap(client.read(8)).order(ByteOrder.LITTLE_ENDIAN);
         final int length = buffer.getInt();
         final int seq = buffer.getInt();
         final byte[] body = client.read(length - 12);

lib/src/main/java/io/github/lonamiwebs/overgram/tl/TLObject.java

@@ -6,5 +6,5 @@ import io.github.lonamiwebs.overgram.utils.BinaryWriter;
 public abstract class TLObject {
     public abstract void serialize(final BinaryWriter writer);
 
-    public abstract void deserialize(final BinaryReader reader);
+    public abstract void deserialize(final BinaryReader reader) throws ClassNotFoundException;
 }

lib/src/main/java/io/github/lonamiwebs/overgram/utils/BinaryReader.java

@@ -1,5 +1,9 @@
 package io.github.lonamiwebs.overgram.utils;
 
+import io.github.lonamiwebs.overgram.tl.TLObject;
+import io.github.lonamiwebs.overgram.tl.Types;
+
+import java.math.BigInteger;
 import java.nio.ByteBuffer;
 import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
@@ -40,6 +44,18 @@ public class BinaryReader {
         return result;
     }
 
+    public BigInteger readInt128() {
+        final byte[] bytes = new byte[16];
+        buffer.get(bytes);
+        return new BigInteger(bytes);
+    }
+
+    public BigInteger readInt256() {
+        final byte[] bytes = new byte[32];
+        buffer.get(bytes);
+        return new BigInteger(bytes);
+    }
+
     public double readDouble() {
         return buffer.getDouble();
     }
@@ -63,7 +79,9 @@ public class BinaryReader {
 
         final byte[] data = new byte[length];
         buffer.get(data);
-        buffer.position(buffer.position() + padding);
+        if (padding > 0) {
+            buffer.position(buffer.position() + 4 - padding);
+        }
         return data;
     }
 
@@ -91,14 +109,16 @@ public class BinaryReader {
         return result;
     }
 
-    public Object readTl() {
+    public TLObject readTl() throws ClassNotFoundException {
-        return null;
+        final TLObject object = Types.getFromId(readInt());
+        object.deserialize(this);
+        return object;
     }
 
-    public List<?> readTlList() {
+    public List<?> readTlList() throws ClassNotFoundException {
         buffer.position(buffer.position() + 4); // vector code
         final int size = buffer.getInt();
-        final List<Object> result = new ArrayList<>(size);
+        final List<TLObject> result = new ArrayList<>(size);
         for (int i = 0; i < size; ++i) {
             result.add(readTl());
         }

lib/src/main/java/io/github/lonamiwebs/overgram/utils/BinaryWriter.java

@@ -3,55 +3,100 @@ package io.github.lonamiwebs.overgram.utils;
 
 import io.github.lonamiwebs.overgram.tl.TLObject;
 
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.math.BigInteger;
 import java.nio.ByteBuffer;
 import java.nio.ByteOrder;
 import java.nio.charset.StandardCharsets;
+import java.util.Arrays;
 import java.util.List;
 
 public class BinaryWriter {
-    private final ByteBuffer buffer;
+
+    private static final ByteOrder ORDER = ByteOrder.LITTLE_ENDIAN;
+
+    private final ByteArrayOutputStream buffer;
 
     public BinaryWriter() {
-        buffer = ByteBuffer.allocate(128);
+        buffer = new ByteArrayOutputStream(128);
-        buffer.order(ByteOrder.LITTLE_ENDIAN);
     }
 
     public void write(final int value) {
-        buffer.putInt(value);
+        try {
+            buffer.write(ByteBuffer.allocate(4).order(ORDER).putInt(value).array());
+        } catch (IOException ignored) {
+            throw new RuntimeException();
+        }
     }
 
     public void write(final long value) {
-        buffer.putLong(value);
+        try {
+            buffer.write(ByteBuffer.allocate(8).order(ORDER).putLong(value).array());
+        } catch (IOException ignored) {
+            throw new RuntimeException();
+        }
+    }
+
+    public void write(final BigInteger value) {
+        final byte[] bytes = value.toByteArray();
+
+        // It's really unlike an int256 has only 16 bytes so we're good
+        final int size = bytes.length > 16 ? 32 : 16;
+        if (ORDER == ByteOrder.BIG_ENDIAN) {
+            for (int i = 0; i < size; ++i) {
+                buffer.write(i < bytes.length ? bytes[i] : 0);
+            }
+        } else {
+            for (int i = size; i-- != 0; ) {
+                buffer.write(i < bytes.length ? bytes[i] : 0);
+            }
+        }
     }
 
     public void write(final double value) {
-        buffer.putDouble(value);
+        try {
+            buffer.write(ByteBuffer.allocate(8).order(ORDER).putDouble(value).array());
+        } catch (IOException ignored) {
+            throw new RuntimeException();
+        }
     }
 
     public void write(final boolean value) {
-        buffer.putInt(value ? 0x997275b5 : 0xbc799737);
+        write(value ? 0x997275b5 : 0xbc799737);
     }
 
     public void write(final byte[] bytes) {
+        try {
             int padding;
             if (bytes.length < 0xfe) {
                 padding = (bytes.length + 1) % 4;
-            buffer.put((byte) bytes.length);
+                buffer.write(bytes.length);
-            buffer.put(bytes);
+                buffer.write(bytes);
             } else {
                 padding = bytes.length % 4;
-            buffer.putInt(bytes.length << 8 | 0xfe);
+                write(bytes.length << 8 | 0xfe);
-            buffer.put(bytes);
+                buffer.write(bytes);
             }
             if (padding != 0) {
                 for (padding = 4 - padding; padding-- != 0; ) {
-                buffer.put((byte) 0);
+                    buffer.write(0);
                 }
             }
+        } catch (IOException ignored) {
+            throw new RuntimeException();
+        }
+    }
+
+    public void writeRaw(final byte[] bytes) {
+        try {
+            buffer.write(bytes);
+        } catch (IOException ignored) {
+        }
     }
 
     public void write(final String string) {
-        buffer.put(StandardCharsets.UTF_8.encode(string));
+        write(StandardCharsets.UTF_8.encode(string).array());
     }
 
     // TODO Handle boxed vs unboxed types (and vector<>)
@@ -88,4 +133,21 @@ public class BinaryWriter {
             throw new UnsupportedOperationException();
         }
     }
+
+    public void clear() {
+        buffer.reset();
+    }
+
+    public int size() {
+        return buffer.size();
+    }
+
+    public byte[] toBytes() {
+        return buffer.toByteArray();
+    }
+
+    @Override
+    public String toString() {
+        return Arrays.toString(toBytes());
+    }
 }