Major plugin refactor and cleanup.

Switched to POCO library for unified platform/library interface.
Deprecated the external module API. It was creating more problems than solving.
Removed most built-in libraries in favor of system libraries for easier maintenance.
Cleaned and secured code with help from static analyzers.

vendor/POCO/NetSSL_OpenSSL/include/Poco/Net/PrivateKeyPassphraseHandler.h

@@ -0,0 +1,84 @@
+//
+// PrivateKeyPassphraseHandler.h
+//
+// Library: NetSSL_OpenSSL
+// Package: SSLCore
+// Module:  PrivateKeyPassphraseHandler
+//
+// Definition of the PrivateKeyPassphraseHandler class.
+//
+// Copyright (c) 2006-2009, Applied Informatics Software Engineering GmbH.
+// and Contributors.
+//
+// SPDX-License-Identifier:	BSL-1.0
+//
+
+
+#ifndef NetSSL_PrivateKeyPassphraseHandler_INCLUDED
+#define NetSSL_PrivateKeyPassphraseHandler_INCLUDED
+
+
+#include "Poco/Net/NetSSL.h"
+
+
+namespace Poco {
+namespace Net {
+
+
+class NetSSL_API PrivateKeyPassphraseHandler
+	/// A passphrase handler is needed whenever the private key of a certificate is loaded and the certificate is protected
+	/// by a passphrase. The PrivateKeyPassphraseHandler's task is to provide that passphrase.
+	/// One can install one's own PrivateKeyPassphraseHandler by implementing this interface. Note that
+	/// in the implementation file of the subclass the following code must be present (assuming you use the namespace My_API 
+	/// and the name of your handler class is MyGuiHandler):
+	///    
+	///    #include "Poco/Net/PrivateKeyFactory.h"
+	///    ...
+	///    POCO_REGISTER_KEYFACTORY(My_API, MyGuiHandler)
+	///
+	/// One can either set the handler directly in the startup code of the main method of ones application by calling
+	///
+	///    SSLManager::instance().initialize(myguiHandler, myInvalidCertificateHandler, mySSLContext)
+	///
+	/// or in case one's application extends Poco::Util::Application one can use an XML configuration and put the following entry
+	/// under the path openSSL.privateKeyPassphraseHandler:
+	///    
+	///    <privateKeyPassphraseHandler>
+	///        <name>MyGuiHandler</name>
+	///        <options>
+	///            [...] // Put optional config params for the handler here
+	///        </options>
+	///    </privateKeyPassphraseHandler>
+	///
+	/// Note that the name of the passphrase handler must be same as the one provided to the POCO_REGISTER_KEYFACTORY macro.
+{
+public:
+	PrivateKeyPassphraseHandler(bool onServerSide);
+		/// Creates the PrivateKeyPassphraseHandler. Automatically registers at the SSLManager::PrivateKeyPassword event.
+
+	virtual ~PrivateKeyPassphraseHandler();
+		/// Destroys the PrivateKeyPassphraseHandler.
+
+	virtual void onPrivateKeyRequested(const void* pSender, std::string& privateKey) = 0;
+		/// Returns the requested private key in the parameter privateKey.
+
+	bool serverSide() const;
+
+private:
+	bool _serverSide;
+};
+
+
+//
+// inlines
+//
+inline bool PrivateKeyPassphraseHandler::serverSide() const
+{
+	return _serverSide;
+}
+
+
+} } // namespace Poco::Net
+
+
+#endif // NetSSL_PrivateKeyPassphraseHandler_INCLUDED