Add OPC UA protocol dissector (#2169)

4 files changed, 88 insertions, 0 deletions

diff --git a/src/include/ndpi_protocol_ids.h b/src/include/ndpi_protocol_ids.h
index 070f0f137..9da6d310e 100644
--- a/src/include/ndpi_protocol_ids.h
+++ b/src/include/ndpi_protocol_ids.h
@@ -388,6 +388,7 @@ typedef enum {
   NDPI_PROTOCOL_TESLA_SERVICES        = 357,
   NDPI_PROTOCOL_PTPV2                 = 358,
   NDPI_PROTOCOL_RTPS                  = 359,
+  NDPI_PROTOCOL_OPC_UA                = 360,
 
 #ifdef CUSTOM_NDPI_PROTOCOLS
 #include "../../../nDPI-custom/custom_ndpi_protocol_ids.h"
diff --git a/src/include/ndpi_protocols.h b/src/include/ndpi_protocols.h
index 75d8f7080..b003ca17b 100644
--- a/src/include/ndpi_protocols.h
+++ b/src/include/ndpi_protocols.h
@@ -253,6 +253,7 @@ void init_ethereum_dissector(struct ndpi_detection_module_struct *ndpi_struct, u
 void init_ptpv2_dissector(struct ndpi_detection_module_struct *ndpi_struct, u_int32_t *id);
 void init_hart_ip_dissector(struct ndpi_detection_module_struct *ndpi_struct, u_int32_t *id);
 void init_rtps_dissector(struct ndpi_detection_module_struct *ndpi_struct, u_int32_t *id);
+void init_opc_ua_dissector(struct ndpi_detection_module_struct *ndpi_struct, u_int32_t *id);
 
 /* ndpi_main.c */
 extern u_int32_t ndpi_ip_port_hash_funct(u_int32_t ip, u_int16_t port);
diff --git a/src/lib/ndpi_main.c b/src/lib/ndpi_main.c
index f7dff3e90..10d4b504b 100644
--- a/src/lib/ndpi_main.c
+++ b/src/lib/ndpi_main.c
@@ -2138,6 +2138,10 @@ static void ndpi_init_protocol_defaults(struct ndpi_detection_module_struct *ndp
 			  "RTPS", NDPI_PROTOCOL_CATEGORY_RPC,
 			  ndpi_build_default_ports(ports_a, 0, 0, 0, 0, 0) /* TCP */,
 			  ndpi_build_default_ports(ports_b, 7401, 0, 0, 0, 0) /* UDP */);
+  ndpi_set_proto_defaults(ndpi_str, 1 /* cleartext */, 0 /* nw proto */, NDPI_PROTOCOL_ACCEPTABLE, NDPI_PROTOCOL_OPC_UA,
+			  "OPC-UA", NDPI_PROTOCOL_CATEGORY_IOT_SCADA,
+			  ndpi_build_default_ports(ports_a, 4840, 0, 0, 0, 0) /* TCP */,
+			  ndpi_build_default_ports(ports_b, 0, 0, 0, 0, 0) /* UDP */);
 
 #ifdef CUSTOM_NDPI_PROTOCOLS
 #include "../../../nDPI-custom/custom_ndpi_main.c"
@@ -5577,6 +5581,9 @@ static int ndpi_callback_init(struct ndpi_detection_module_struct *ndpi_str) {
   /* Real-time Publish-Subscribe Protocol */
   init_rtps_dissector(ndpi_str, &a);
 
+  /* OPC Unified Architecture */
+  init_opc_ua_dissector(ndpi_str, &a);
+
 #ifdef CUSTOM_NDPI_PROTOCOLS
 #include "../../../nDPI-custom/custom_ndpi_main_init.c"
 #endif
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;
+}