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/src/KeyFileHandler.cpp

@@ -0,0 +1,61 @@
+//
+// KeyFileHandler.cpp
+//
+// Library: NetSSL_OpenSSL
+// Package: SSLCore
+// Module:  KeyFileHandler
+//
+// Copyright (c) 2006-2009, Applied Informatics Software Engineering GmbH.
+// and Contributors.
+//
+// SPDX-License-Identifier:	BSL-1.0
+//
+
+
+#include "Poco/Net/KeyFileHandler.h"
+#include "Poco/Net/SSLManager.h"
+#include "Poco/File.h"
+#include "Poco/Util/AbstractConfiguration.h"
+#include "Poco/Util/Application.h"
+#include "Poco/Util/OptionException.h"
+
+
+namespace Poco {
+namespace Net {
+
+
+const std::string KeyFileHandler::CFG_PRIV_KEY_FILE("privateKeyPassphraseHandler.options.password");
+
+
+KeyFileHandler::KeyFileHandler(bool server):PrivateKeyPassphraseHandler(server)
+{
+}
+
+
+KeyFileHandler::~KeyFileHandler()
+{
+}
+
+
+void KeyFileHandler::onPrivateKeyRequested(const void* pSender, std::string& privateKey)
+{
+	try
+	{
+		Poco::Util::AbstractConfiguration& config = Poco::Util::Application::instance().config();
+		std::string prefix = serverSide() ? SSLManager::CFG_SERVER_PREFIX : SSLManager::CFG_CLIENT_PREFIX;
+		if (!config.hasProperty(prefix + CFG_PRIV_KEY_FILE))
+			throw Poco::Util::EmptyOptionException(std::string("Missing Configuration Entry: ") + prefix + CFG_PRIV_KEY_FILE);
+		
+		privateKey = config.getString(prefix + CFG_PRIV_KEY_FILE);
+	}
+	catch (Poco::NullPointerException&)
+	{
+		throw Poco::IllegalStateException(
+			"An application configuration is required to obtain the private key passphrase, "
+			"but no Poco::Util::Application instance is available."
+			);
+	}
+}
+
+
+} } // namespace Poco::Net