Add Ether-S-Bus protocol dissector (#2200)

1 files changed, 74 insertions, 0 deletions

diff --git a/src/lib/protocols/ethersbus.c b/src/lib/protocols/ethersbus.c
new file mode 100644
index 000000000..4366c6e8b
--- /dev/null
+++ b/src/lib/protocols/ethersbus.c
@@ -0,0 +1,74 @@
+/*
+ * ethersbus.c
+ *
+ * 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_ETHERSBUS
+
+#include "ndpi_api.h"
+#include "ndpi_private.h"
+
+static void ndpi_int_ethersbus_add_connection(struct ndpi_detection_module_struct *ndpi_struct,
+                                              struct ndpi_flow_struct *flow)
+{
+  NDPI_LOG_INFO(ndpi_struct, "found Ether-S-Bus\n");
+  ndpi_set_detected_protocol(ndpi_struct, flow,
+                             NDPI_PROTOCOL_ETHERSBUS, NDPI_PROTOCOL_UNKNOWN,
+                             NDPI_CONFIDENCE_DPI);
+}
+
+static void ndpi_search_ethersbus(struct ndpi_detection_module_struct *ndpi_struct,
+                                  struct ndpi_flow_struct *flow)
+{
+  struct ndpi_packet_struct const * const packet = &ndpi_struct->packet;
+
+  NDPI_LOG_DBG(ndpi_struct, "search Ether-S-Bus\n");
+
+  if ((packet->payload_packet_len > 12) &&
+      (ntohl(get_u_int32_t(packet->payload,0)) == packet->payload_packet_len) &&
+      (packet->payload[4] < 2) && (packet->payload[5] == 0))
+  {
+    u_int16_t crc = ndpi_crc16_xmodem(packet->payload,packet->payload_packet_len-2);
+    if (get_u_int16_t(packet->payload,packet->payload_packet_len-2) == htons(crc))
+    {
+      ndpi_int_ethersbus_add_connection(ndpi_struct, flow);
+      return;
+    }
+  }
+
+  NDPI_EXCLUDE_PROTO(ndpi_struct, flow);
+}
+
+void init_ethersbus_dissector(struct ndpi_detection_module_struct *ndpi_struct,
+                              u_int32_t *id)
+{
+  ndpi_set_bitmask_protocol_detection("Ether-S-Bus", ndpi_struct, *id,
+                                      NDPI_PROTOCOL_ETHERSBUS,
+                                      ndpi_search_ethersbus,
+                                      NDPI_SELECTION_BITMASK_PROTOCOL_V4_V6_UDP_WITH_PAYLOAD,
+                                      SAVE_DETECTION_BITMASK_AS_UNKNOWN,
+                                      ADD_TO_DETECTION_BITMASK);
+
+  *id += 1;
+}