Merge branch 'nxcomp'

1 files changed, 166 insertions, 0 deletions

diff --git a/nxcomp/ClientReadBuffer.cpp b/nxcomp/ClientReadBuffer.cpp
new file mode 100644
index 000000000..b32033b17
--- /dev/null
+++ b/nxcomp/ClientReadBuffer.cpp
@@ -0,0 +1,166 @@
+/**************************************************************************/
+/*                                                                        */
+/* Copyright (c) 2001, 2010 NoMachine, http://www.nomachine.com/.         */
+/*                                                                        */
+/* NXCOMP, NX protocol compression and NX extensions to this software     */
+/* are copyright of NoMachine. Redistribution and use of the present      */
+/* software is allowed according to terms specified in the file LICENSE   */
+/* which comes in the source distribution.                                */
+/*                                                                        */
+/* Check http://www.nomachine.com/licensing.html for applicability.       */
+/*                                                                        */
+/* NX and NoMachine are trademarks of Medialogic S.p.A.                   */
+/*                                                                        */
+/* All rights reserved.                                                   */
+/*                                                                        */
+/**************************************************************************/
+
+#include "ClientReadBuffer.h"
+
+#include "ClientChannel.h"
+
+#define PANIC
+#define WARNING
+#undef  TEST
+#undef  DEBUG
+
+unsigned int ClientReadBuffer::suggestedLength(unsigned int pendingLength)
+{
+  //
+  // Even if the pending data is not
+  // enough to make a complete message,
+  // resize the buffer to accomodate
+  // it all.
+  //
+
+  unsigned int readLength = pendingLength;
+
+  if (pendingLength < remaining_)
+  {
+    readLength = remaining_;
+  }
+
+  return readLength;
+}  
+
+int ClientReadBuffer::locateMessage(const unsigned char *start,
+                                        const unsigned char *end,
+                                            unsigned int &controlLength,
+                                                unsigned int &dataLength,
+                                                    unsigned int &trailerLength)
+{
+  unsigned int size = end - start;
+
+  #ifdef TEST
+  *logofs << "ClientReadBuffer: Locating message for FD#"
+          << transport_ -> fd() << " with " << size
+          << " bytes.\n" << logofs_flush;
+  #endif
+
+  if (firstMessage_)
+  {
+    if (size < 12)
+    {
+      remaining_ = 12 - size;
+
+      #ifdef TEST
+      *logofs << "ClientReadBuffer: No message was located "
+              << "with remaining " << remaining_ << ".\n"
+              << logofs_flush;
+      #endif
+
+      return 0;
+    }
+
+    if (*start == 0x42)
+    {
+      bigEndian_ = 1;
+    }
+    else
+    {
+      bigEndian_ = 0;
+    }
+
+    channel_ -> setBigEndian(bigEndian_);
+
+    dataLength = 12 + RoundUp4(GetUINT(start + 6, bigEndian_)) +
+                          RoundUp4(GetUINT(start + 8, bigEndian_));
+
+    //
+    // Send the data immediately if this is unlikely
+    // to be a X connection attempt.
+    //
+
+    if (dataLength > 4096)
+    {
+      #ifdef WARNING
+      *logofs << "ClientReadBuffer: WARNING! Flushing suspicious X "
+              << "connection with first request of " << dataLength
+              << " bytes.\n" << logofs_flush;
+      #endif
+
+      dataLength = size;
+    }
+  }
+  else
+  {
+    if (size < 4)
+    {
+      remaining_ = 4 - size;
+
+      #ifdef TEST
+      *logofs << "ClientReadBuffer: No message was located "
+              << "with remaining " << remaining_ << ".\n"
+              << logofs_flush;
+      #endif
+
+      return 0;
+    }
+
+    dataLength = (GetUINT(start + 2, bigEndian_) << 2);
+
+    if (dataLength < 4)
+    {
+      #ifdef TEST
+      *logofs << "ClientReadBuffer: WARNING! Assuming length 4 "
+              << "for suspicious message of length " << dataLength
+              << ".\n" << logofs_flush;
+      #endif
+
+      dataLength = 4;
+    }
+  }
+
+  #ifdef TEST
+  *logofs << "ClientReadBuffer: Length of the next message is "
+          << dataLength << ".\n" << logofs_flush;
+  #endif
+
+  if (size < dataLength)
+  {
+    remaining_ = dataLength - size;
+
+    #ifdef TEST
+    *logofs << "ClientReadBuffer: No message was located "
+            << "with remaining " << remaining_ << ".\n"
+            << logofs_flush;
+    #endif
+
+    return 0;
+  }
+
+  firstMessage_ = 0;
+
+  controlLength = 0;
+  trailerLength = 0;
+
+  remaining_ = 0;
+
+  #ifdef TEST
+  *logofs << "ClientReadBuffer: Located message with "
+          << "remaining " << remaining_ << ".\n"
+          << logofs_flush;
+  #endif
+
+  return 1;
+}