[Development] Implement secure TLS streams.


git-svn-id: svn://svn.code.sf.net/p/tigervnc/code/trunk@4044 3789f03b-4d11-0410-bbf8-ca57d06f2519
diff --git a/common/rdr/TLSOutStream.cxx b/common/rdr/TLSOutStream.cxx
new file mode 100644
index 0000000..59edf15
--- /dev/null
+++ b/common/rdr/TLSOutStream.cxx
@@ -0,0 +1,106 @@
+/* Copyright (C) 2002-2005 RealVNC Ltd.  All Rights Reserved.
+ * Copyright (C) 2005 Martin Koegler
+ * Copyright (C) 2010 TigerVNC Team
+ * 
+ * This is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ * 
+ * This software is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this software; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307,
+ * USA.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <rdr/Exception.h>
+#include <rdr/TLSException.h>
+#include <rdr/TLSOutStream.h>
+
+#ifdef HAVE_GNUTLS
+using namespace rdr;
+
+enum { DEFAULT_BUF_SIZE = 16384 };
+
+ssize_t rdr::gnutls_OutStream_push(gnutls_transport_ptr str, const void* data,
+				   size_t size)
+{
+  OutStream* out = (OutStream*) str;
+  out->writeBytes(data, size);
+  out->flush();
+  return size;
+}
+
+TLSOutStream::TLSOutStream(OutStream* _out, gnutls_session _session)
+  : session(_session), out(_out), bufSize(DEFAULT_BUF_SIZE), offset(0)
+{
+  ptr = start = new U8[bufSize];
+  end = start + bufSize;
+}
+
+TLSOutStream::~TLSOutStream()
+{
+#if 0
+  try {
+//    flush();
+  } catch (Exception&) {
+  }
+#endif
+  delete [] start;
+}
+
+int TLSOutStream::length()
+{
+  return offset + ptr - start;
+}
+
+void TLSOutStream::flush()
+{
+  U8* sentUpTo = start;
+  while (sentUpTo < ptr) {
+    int n = writeTLS(sentUpTo, ptr - sentUpTo);
+    sentUpTo += n;
+    offset += n;
+  }
+
+  ptr = start;
+  out->flush();
+}
+
+int TLSOutStream::overrun(int itemSize, int nItems)
+{
+  if (itemSize > bufSize)
+    throw Exception("TLSOutStream overrun: max itemSize exceeded");
+
+  flush();
+
+  if (itemSize * nItems > end - ptr)
+    nItems = (end - ptr) / itemSize;
+
+  return nItems;
+}
+
+int TLSOutStream::writeTLS(const U8* data, int length)
+{
+  int n;
+
+  n = gnutls_record_send(session, data, length);
+  if (n == GNUTLS_E_INTERRUPTED || n == GNUTLS_E_AGAIN)
+    return 0;
+
+  if (n < 0)
+    throw TLSException("writeTLS", n);
+
+  return n;
+}
+
+#endif