fix keylog

Author: jogibear9988

src/S7CommPlusDriver/Net/S7Client.cs

@@ -139,12 +139,14 @@ public int SslActivate()
 					return S7Consts.errOpenSSL;
 				}
 				m_sslconn = new OpenSSLConnector(m_ptr_ctx, this);
-				m_sslconn.ExpectConnect();
-
-				// Keylog callback setzen
-				if (WriteSslKeyToFile)
-					m_keylog_cb = new Native.SSL_CTX_keylog_cb_func(SSL_CTX_keylog_cb);
-				Native.SSL_CTX_set_keylog_callback(m_ptr_ctx, m_keylog_cb);
+				m_sslconn.ExpectConnect();
+
+				// Keylog callback setzen
+				if (WriteSslKeyToFile)
+				{
+					m_keylog_cb = new Native.SSL_CTX_keylog_cb_func(SSL_CTX_keylog_cb);
+					Native.SSL_CTX_set_keylog_callback(m_ptr_ctx, m_keylog_cb);
+				}
 
 				m_SslActive = true;
 			}