:bulb: Add mongodb protocol dissector (#1048)

1 files changed, 139 insertions, 0 deletions

diff --git a/src/lib/protocols/mongodb.c b/src/lib/protocols/mongodb.c
new file mode 100644
index 000000000..69f18ca7f
--- /dev/null
+++ b/src/lib/protocols/mongodb.c
@@ -0,0 +1,139 @@
+/*
+ * mongodb.c
+ *
+ * Copyright (C) 2018 by Leonn Paiva <leonn.paiva@gmail.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_MONGODB
+
+#include "ndpi_api.h"
+
+enum mongo_opcodes
+{
+    OP_REPLY = 1,
+    OP_UPDATE = 2001,
+    OP_INSERT = 2002,
+    RESERVED = 2003,
+    OP_QUERY = 2004,
+    OP_GET_MORE = 2005,
+    OP_DELETE = 2006,
+    OP_KILL_CURSORS = 2007,
+    OP_MSG = 2013
+};
+
+struct mongo_message_header
+{
+    uint32_t message_length;
+    uint32_t request_id;
+    uint32_t response_to;
+    enum mongo_opcodes op_code;
+};
+
+static void set_mongodb_detected(struct ndpi_detection_module_struct *ndpi_struct,
+           struct ndpi_flow_struct *flow) {
+
+  if(flow->detected_protocol_stack[0] == NDPI_PROTOCOL_UNKNOWN) {
+    ndpi_search_tcp_or_udp(ndpi_struct, flow);
+
+    /* If no custom protocol has been detected */
+    /* if(flow->detected_protocol_stack[0] == NDPI_PROTOCOL_UNKNOWN) */
+      ndpi_int_reset_protocol(flow);
+      ndpi_set_detected_protocol(ndpi_struct, flow, NDPI_PROTOCOL_MONGODB, flow->guessed_host_protocol_id);
+  }
+}
+
+
+/*************************************************************************************************/
+
+static void ndpi_check_mongodb(struct ndpi_detection_module_struct *ndpi_struct,
+			   struct ndpi_flow_struct *flow) {
+  struct mongo_message_header mongodb_hdr;
+  struct ndpi_packet_struct *packet = &flow->packet;
+
+  if (packet->payload_packet_len <= sizeof(mongodb_hdr)) {
+    NDPI_EXCLUDE_PROTO(ndpi_struct, flow);
+    return;
+  }
+
+  memcpy(&mongodb_hdr, packet->payload, sizeof(struct mongo_message_header));
+
+  mongodb_hdr.message_length = ntohs(mongodb_hdr.message_length);
+
+  if (mongodb_hdr.message_length < 4) {
+    NDPI_LOG_DBG(ndpi_struct, "Invalid MONGODB length");
+    NDPI_EXCLUDE_PROTO(ndpi_struct, flow);
+    return;
+  }
+
+  switch(mongodb_hdr.op_code) {
+    case OP_REPLY:
+    case OP_UPDATE:
+    case OP_INSERT:
+    case RESERVED:
+    case OP_QUERY:
+    case OP_GET_MORE:
+    case OP_DELETE:
+    case OP_KILL_CURSORS:
+    case OP_MSG:
+      set_mongodb_detected(ndpi_struct, flow);
+      break;
+    default:
+      NDPI_LOG_DBG(ndpi_struct, "Invalid MONGODB length");
+      NDPI_EXCLUDE_PROTO(ndpi_struct, flow);
+      break;
+  }
+}
+
+void ndpi_search_mongodb(struct ndpi_detection_module_struct *ndpi_struct,
+ struct ndpi_flow_struct *flow)
+{
+  struct ndpi_packet_struct *packet = &flow->packet;
+
+  // Break after 6 packets.
+  if(flow->packet_counter > 6) {
+    NDPI_EXCLUDE_PROTO(ndpi_struct, flow);
+    return;
+  }
+
+  if(packet->detected_protocol_stack[0] != NDPI_PROTOCOL_UNKNOWN) {
+    return;
+  }
+
+  NDPI_LOG_DBG(ndpi_struct, "search MongoDB\n");
+  ndpi_check_mongodb(ndpi_struct, flow);
+
+  return;
+}
+
+/* ********************************* */
+
+
+void init_mongodb_dissector(struct ndpi_detection_module_struct *ndpi_struct,
+  u_int32_t *id, NDPI_PROTOCOL_BITMASK *detection_bitmask)
+{
+  ndpi_set_bitmask_protocol_detection("MongoDB", ndpi_struct, detection_bitmask,
+    *id, NDPI_PROTOCOL_MONGODB, ndpi_search_mongodb,
+    NDPI_SELECTION_BITMASK_PROTOCOL_V4_V6_TCP_WITH_PAYLOAD,
+    SAVE_DETECTION_BITMASK_AS_UNKNOWN,
+    ADD_TO_DETECTION_BITMASK);
+
+  *id += 1;
+}