BitStreams

config.json

@@ -13,7 +13,7 @@
 				"host": "0.0.0.0",
 				"port": 7777,
 				"hostname": "Python > C",
-				"password": "test",
+				"password": "",
 				"rcon_password": "changeme",
 				"max_players": 50,
 				"mode": "debug",

notes/dumps/1586009798.log

@@ -62,7 +62,7 @@ BitStream::ReadBit()      # hasAcks
 CreateInternalPacketFromBitStream()
  caller_addr: 0x0045FB0D
  time: 22 39423557
- bitStream->numberOfBitsAllocated: 176
+ bitStream->numberOfBitsAllocated: 176  # 22 bytes
  bitStream->numberOfBitsUsed: 176
  bitStream->readOffset: 1
  bitStream->data:

sampy/client/query.py

@@ -96,7 +96,7 @@ class QueryClient(BaseClient):
                 p["ping"]
             ]
         
-        return packet + struct.pack(b"<H" + (b"cc%dsII" * data[0]) % tuple(len(p["nick"]) for p in players), *data)
+        return packet + struct.pack(b"<H" + (b"BB%dsII" * data[0]) % tuple(len(p["nick"]) for p in players), *data)
 
     async def query_p(self, packet: bytes) -> bytes:
         return packet

sampy/raknet/bitstream.py

@@ -7,91 +7,103 @@ logger = logging.getLogger(__name__)
 
 class Bitstream:
     def __init__(self, data: bytes = b""):
-        self.offset = 0
+        self._offset = 0
-        self.buffer = array("B", data)
+        self._buffer = bytearray(data) # array("B", data)
     
-    # This is not finished.. would like to implement bit_length support
+    def _can_access_bits(self, bits_to_access: int) -> bool:
-    def write(self, value: bool):
+        return self._offset + bits_to_access <= len(self._buffer) << 3
-        offset = self.offset % 8
 
-        if self.offset // 8 == len(self.buffer):
+    def write_bit(self, value: bool) -> bool:
-            self.buffer.append(0)
+        if not self._can_access_bits(1):
+            return False
+
+        mask = (1 << (7 - (self._offset % 8)))
+        if value:
+            self._buffer[self._offset >> 3] |= mask
+        else:
+            self._buffer[self._offset >> 3] &= ~mask
+
+        self._offset += 1
+        return True
+
+    def read_bit(self) -> (bool, bool):
+        if not self._can_access_bits(1):
+            return False, False
+
+        mask = (1 << (7 - (self._offset % 8)))
+        value = self._buffer[self._offset >> 3] & mask
+
+        self._offset += 1
+        return True, value > 0
+    
+    def write(self, value: bytes, bit_length: int) -> bool:
+        if not self._can_access_bits(bit_length):
+            return False
         
-        self.offset += 1
+        if len(value) << 3 < bit_length:
+            return False
 
-        if value == False:
+        byte_from = self._offset >> 3
-            return
+        byte_to = (self._offset + bit_length + 7) >> 3
+
+        bits_written = 0
+
+        for byte_index in range(byte_from, byte_to, 1):
+            byte = self._buffer[byte_index]
+            for bit_index in range(self._offset % 8, 8, 1):
+                mask = 1 << (7 - bit_index)
+                bit = value[bits_written >> 3] & (1 << ((7 - bits_written) % 8))
+                if bit:
+                    byte |= mask
+                else:
+                    byte &= ~mask
+
+                self._offset += 1
+                bits_written += 1
+
+                if bits_written >= bit_length:
+                    break
+
+            self._buffer[byte_index] = byte
+
+        return True
+
+    def read(self, bit_length: int) -> (bool, bytes):
+        if not self._can_access_bits(bit_length):
+            return False, b""
         
-        mask = 1 << (7 - offset)
+        byte_from = self._offset >> 3
-        self.buffer[-1] |= mask
+        byte_to = (self._offset + bit_length + 7) >> 3
 
-    """
+        # Since python doesnt have a max number size,
-    def write(self, value: int, bit_length: int):
+        #  we can read the bits we need and store them into a number,
-        offset = self.offset % 8
+        #  then convert the number to bytes (as they are all in the same for python)
-
-        shifts = offset + bit_length
-        while shifts > 8:
-
-
-        if offset == 0:
-            self.buffer.append(0)
-        
-        v = self.buffer[buffer_index]
-        
-        mask = (1 << ((self.offset % 8) + 1))
-    """
-        
-
-    def read(self, bit_length: int) -> int:
-        byte_read_from = self.offset // 8
-        byte_read_to = (self.offset + bit_length - 1) // 8
-        bytes_to_read = byte_read_to - byte_read_from + 1
-
-        if byte_read_to >= len(self.buffer):
-            logger.debug("byte_read_to: %d" % byte_read_to)
-            logger.debug("len(self.buffer): %d" % len(self.buffer))
-            raise Exception("Reading beyond the buffer")
-        
         value = 0
-        shifts = bytes_to_read - 1
-        while shifts >= 0:
-            value += self.buffer[byte_read_to - shifts] << (shifts * 8)
-            shifts -= 1
-        
-        value <<= self.offset % 8
-        value &= (1 << (8 * bytes_to_read)) - 1
-        value >>= (bytes_to_read * 8) - bit_length
 
-        self.offset += bit_length
+        for byte_index in range(byte_from, byte_to, 1):
-        return value
+            for bit_index in range(self._offset % 8, 8, 1):
+                mask = 1 << (7 - bit_index)
+                bit = self._buffer[self._offset >> 3] & (1 << ((7 - self._offset) % 8))
+                value = (value << 1) + bit
+
+                self._offset += 1
+
+                if self._offset >= bit_length:
+                    break
+
+        #if self._offset % 8 == 0:
+            #value += 
+        
+        return True, value.to_bytes((bit_length + 7) >> 3, "big") # bytes(value)
     
-    def read_compressed(self, bit_length: int, unsigned: bool):
+    def read_compressed(self):
         pass
-    
-    def read_aligned_bytes(self, byte_length: int) -> bytes:
-        if byte_length <= 0:
-            return b""
-        
-        self.align_to_byte()
 
-        if self.offset + (byte_length * 8) > len(self.buffer):
+    def pretty(self) -> str:
-            logger.debug("Reading beyond the buffer")
+        b = bytearray(" " + "  ".join(" ".join(format(c, "08b")) for c in self._buffer) + " ", "ascii")
-            return b""
+        m = self._offset * 2 + (self._offset >> 3) - (self._offset // (max(1, len(self._buffer)) * 8))
-
+        b[m] = 124
-        byte_read_from = self.offset // 8
-        byte_read_to = byte_read_from + byte_length
-        self.offset += byte_length
-
-        return self.buffer[byte_read_from:byte_read_to + 1]
-
-    def align_to_byte(self):
-        if self.offset % 8 != 0:
-            self.offset += 8 - (self.offset % 8)
-
-    def __repr__(self) -> str:
-        b = bytearray(" " + "  ".join(" ".join(format(c, "08b")) for c in self.buffer) + " ", "ascii")
-        m = self.offset * 2 + (self.offset // 8) - (self.offset // (max(1, len(self.buffer)) * 8))
-        #b[m] = 91 # [
-        #b[m + 2] = 93 # ]
-        b[m] = 124 # |
         return b.decode()
+    
+    def __repr__(self) -> str:
+        return "<Bitstream addr:0x%012x offset:%d len:%d>" % (id(self), self._offset, len(self._buffer) << 3)

sampy/server/__init__.py

@@ -22,7 +22,7 @@ class Server:
         self.socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM, socket.IPPROTO_UDP)
         self.socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
         self.socket.bind((self.config.host, self.config.port))
-        self.socket.setblocking(0) # TODO: Check if needed? I dont fully understand this "feature"
+        self.socket.setblocking(0)
         logger.debug("Socket created")
 
     async def on_command(self, cmd: str):

test.py

@@ -1,30 +1,85 @@
 from sampy.raknet.bitstream import Bitstream
 
-a = Bitstream()
+bitstream = Bitstream(b"\x00" * 4)
-"""
+MAGIC_BYTES = b"\x01\xff\x02"
-a.buffer.append(0x42)
+MAGIC_BITS = [int(bit) for bit in " ".join([format(byte, "08b") for byte in MAGIC_BYTES]) if bit in ("0", "1")]
-a.buffer.append(0x13)
+fail = 0
-a.buffer.append(0xFF)
-a.buffer.append(0xAC)
-a.buffer.append(0x00)
-a.buffer.append(0x69)
-"""
-"""
-a.write(1)
-a.write(0)
-a.write(1)
-a.write(1)
-a.write(1)
-a.write(1)
-a.write(0)
-a.write(1)
 
-a.write(1)
+def print_pretty(prefix, msg):
-"""
+    prefix += " " * (40 - len(prefix))
+    print(prefix, msg)
 
-data = [int(x, 16) for x in "00 00 42 90 0b 61 61 61 61 62 62 62 62 63 63 63 63 66 66 66 66 00".split(" ")]
+def reset_bitstream():
+    bitstream._buffer = bytearray(b"\x00" * len(bitstream._buffer))
+    bitstream._offset = 0
 
-for b in data:
+def test_write_bit(var_bits):
-    a.buffer.append(b)
+    global fail
+    print_pretty("<Test bitstream.write_bit:in>", bitstream.pretty())
+    for bit in var_bits:
+        if not bitstream.write_bit(bit):
+            print_pretty("<Test bitstream.write_bit>", "Failed")
+            fail += 1
+    print_pretty("<Test bitstream.write_bit:out>", bitstream.pretty())
 
-print(a)
+def test_read_bit(var_compare_bits):
+    global fail
+    print_pretty("<Test bitstream.read_bit:in>", bitstream.pretty())
+    for bit in var_compare_bits:
+        ok, bit2 = bitstream.read_bit()
+        if not ok:
+            print_pretty("<Test bitstream.read_bit>", "Failed (ok)")
+            fail += 1
+            continue
+        if bit2 != bit:
+            print_pretty("<Test bitstream.read_bit>", "Failed (match)")
+            fail += 1
+            continue
+    print_pretty("<Test bitstream.read_bit:out>", bitstream.pretty())
+
+def test_write(var_bytes):
+    global fail
+    print_pretty("<Test bitstream.write:in>", bitstream.pretty())
+    if not bitstream.write(var_bytes, len(var_bytes) << 3):
+        print_pretty("<Test bitstream.write>", "Failed")
+        fail += 1
+    print_pretty("<Test bitstream.write:out>", bitstream.pretty())
+
+def test_read(var_compare_bytes):
+    global fail
+    print_pretty("<Test bitstream.read:in>", bitstream.pretty())
+    ok, bytez = bitstream.read(len(var_compare_bytes) << 3)
+    if ok:
+        print(var_compare_bytes, bytez)
+        if bytez != var_compare_bytes:
+            print_pretty("<Test bitstream.read>", "Failed (match)")
+            fail += 1
+    else:
+        print_pretty("<Test bitstream.read>", "Failed (ok)")
+        fail += 1
+    print_pretty("<Test bitstream.read:out>", bitstream.pretty())
+
+def test_rw_bit(offset):
+    bitstream._offset = offset
+    test_write_bit(MAGIC_BITS)
+    bitstream._offset = offset
+    test_read_bit(MAGIC_BITS)
+
+def test_rw_bytes(offset):
+    bitstream._offset = offset
+    test_write(MAGIC_BYTES)
+    bitstream._offset = offset
+    test_read(MAGIC_BYTES)
+
+# Test all edges
+for i in range(9):
+    reset_bitstream()
+    test_rw_bit(i)
+
+reset_bitstream()
+
+for i in range(9):
+    reset_bitstream()
+    test_rw_bytes(i)
+
+print("Failed: %d" % fail)