Changeset 1336 for code/branches/merge/src/network/PacketDecoder.cc

Timestamp:

May 20, 2008, 5:58:37 PM (16 years ago)

Author:

scheusso

Message:

added crc checksum testing for submitted gamestates (can also be used for other packet types)

File:

• code/branches/merge/src/network/PacketDecoder.cc (modified) (2 diffs)

code/branches/merge/src/network/PacketDecoder.cc

@@ -88 +88 @@
       return decodeConnectRequest( packet, clientId );
     }
+    return false;
+  }
+  
+  bool PacketDecoder::testAndRemoveCRC(ENetPacket *packet){
+    uint32_t submittetcrc;
+    int dataLength = packet->dataLength;
+    // get the submittet crc code
+    memcpy(&submittetcrc, &packet->data[dataLength-sizeof(uint32_t)], sizeof(uint32_t));
+    unsigned char *data = packet->data;
+    uint32_t crc32=calcCRC(data, packet->dataLength-sizeof(uint32_t));
+    // now append the crc to the packet data
+    if(crc32==submittetcrc){
+      dataLength-=sizeof(uint32_t);
+      enet_packet_resize(packet, dataLength);
+      return true;
+    }
+    COUT(3) << "gamestate crc: " << crc32 << std::endl;
+    COUT(3) << "submitted crc: " << submittetcrc << std::endl;
     return false;
   }
@@ -157 +175 @@
   void PacketDecoder::gstate( ENetPacket* packet, int clientID )
   {
+    if(!testAndRemoveCRC(packet)){
+      COUT(3) << "crc test of gamestate failed - dropping packet" << std::endl;
+      return;
+    }
     GameStateCompressed* currentState = NULL;
     currentState = new GameStateCompressed;