Add OPC UA protocol dissector (#2169)

1 files changed, 79 insertions, 0 deletions

diff --git a/src/lib/protocols/opc-ua.c b/src/lib/protocols/opc-ua.c
new file mode 100644
index 000000000..8f2ab50a6
--- /dev/null
+++ b/src/lib/protocols/opc-ua.c
@@ -0,0 +1,79 @@
+/*
+ * opc-ua.c
+ *
+ * OPC Unified Architecture
+ * 
+ * Copyright (C) 2023 - ntop.org
+ * Copyright (C) 2023 - V.G <jacendi@protonmail.com>
+ *
+ * This file is part of nDPI, an open source deep packet inspection
+ * library based on the OpenDPI and PACE technology by ipoque GmbH
+ *
+ * nDPI is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * nDPI 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 Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with nDPI.  If not, see <http://www.gnu.org/licenses/>.
+ * 
+ */
+
+#include "ndpi_protocol_ids.h"
+
+#define NDPI_CURRENT_PROTO NDPI_PROTOCOL_OPC_UA
+
+#include "ndpi_api.h"
+#include "ndpi_private.h"
+
+static void ndpi_int_opc_ua_add_connection(struct ndpi_detection_module_struct *ndpi_struct,
+                                           struct ndpi_flow_struct *flow)
+{
+  NDPI_LOG_INFO(ndpi_struct, "found OPC-UA\n");
+  ndpi_set_detected_protocol(ndpi_struct, flow,
+                             NDPI_PROTOCOL_OPC_UA, NDPI_PROTOCOL_UNKNOWN,
+                             NDPI_CONFIDENCE_DPI);
+}
+
+static void ndpi_search_opc_ua(struct ndpi_detection_module_struct *ndpi_struct,
+                               struct ndpi_flow_struct *flow)
+{
+  struct ndpi_packet_struct const * const packet = &ndpi_struct->packet;
+
+  /* Shortest OPC UA packet I've ever seen */
+  if (packet->payload_packet_len >= 16) {
+    /* Each OPC UA MessageChunk starts with a 3 byte ASCII code that defines 
+     * the MessageType. The 4th byte is nowadays ignored and must always be set to 
+     * ASCII character 'F'
+     */
+     if ((memcmp(packet->payload, "HELF", 4) == 0) || 
+         (memcmp(packet->payload, "ACKF", 4) == 0) ||
+         (memcmp(packet->payload, "RHEF", 4) == 0) || 
+         (memcmp(packet->payload, "OPNF", 4) == 0) ||
+         (memcmp(packet->payload, "MSGF", 4) == 0) || 
+         (memcmp(packet->payload, "ERRF", 4) == 0) ||
+         (memcmp(packet->payload, "CLOF", 4) == 0))
+    {
+      ndpi_int_opc_ua_add_connection(ndpi_struct, flow);
+      return;
+    }
+  }
+
+  NDPI_EXCLUDE_PROTO(ndpi_struct, flow);
+}
+
+void init_opc_ua_dissector(struct ndpi_detection_module_struct *ndpi_struct, u_int32_t *id)
+{
+  ndpi_set_bitmask_protocol_detection("OPC-UA", ndpi_struct, *id,
+				      NDPI_PROTOCOL_OPC_UA,
+				      ndpi_search_opc_ua,
+				      NDPI_SELECTION_BITMASK_PROTOCOL_V4_V6_TCP_WITH_PAYLOAD_WITHOUT_RETRANSMISSION,
+				      SAVE_DETECTION_BITMASK_AS_UNKNOWN,
+				      ADD_TO_DETECTION_BITMASK);
+  *id += 1;
+}