Added proprietary Agora Software Defined Real-time Network (SD-RTN) protocol dissector. (#1520)

Signed-off-by: lns <matzeton@googlemail.com>

1 files changed, 97 insertions, 0 deletions

diff --git a/src/lib/protocols/sd_rtn.c b/src/lib/protocols/sd_rtn.c
new file mode 100644
index 000000000..1ddd6af06
--- /dev/null
+++ b/src/lib/protocols/sd_rtn.c
@@ -0,0 +1,97 @@
+/*
+ * sd_rtn.c
+ *
+ * Copyright (C) 2011-22 - ntop.org
+ *
+ * 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_SD_RTN
+
+#include "ndpi_api.h"
+
+static void ndpi_int_sd_rtn_add_connection(struct ndpi_detection_module_struct * const ndpi_struct,
+                                           struct ndpi_flow_struct * const flow)
+{
+  NDPI_LOG_INFO(ndpi_struct, "found Software Defined Real-time Network (SD-RTN)\n");
+  ndpi_set_detected_protocol(ndpi_struct, flow,
+                             NDPI_PROTOCOL_SD_RTN,
+                             NDPI_PROTOCOL_UNKNOWN,
+                             NDPI_CONFIDENCE_DPI);
+}
+
+static int ndpi_int_sd_rtn_dissect_sni(struct ndpi_flow_struct * const flow,
+                                       u_int8_t const * const payload,
+                                       u_int32_t payload_len)
+{
+  u_int32_t sni_len = ntohs(get_u_int16_t(payload, 16));
+
+  if (sni_len + 19 > payload_len)
+  {
+    return -1;
+  }
+
+  if (payload[18] != 0x00)
+  {
+    return -1;
+  }
+
+  ndpi_hostname_sni_set(flow, &payload[19], sni_len);
+
+  return 0;
+}
+
+void ndpi_search_sd_rtn(struct ndpi_detection_module_struct *ndpi_struct,
+                        struct ndpi_flow_struct *flow)
+{
+  struct ndpi_packet_struct * const packet = &ndpi_struct->packet;
+
+  NDPI_LOG_DBG(ndpi_struct, "search Software Defined Real-time Network (SD-RTN)\n");
+
+  if (packet->udp != NULL)
+  {
+    if (packet->payload_packet_len >= 20
+        && packet->payload[6] == 0x21
+        && ntohl(get_u_int32_t(packet->payload, 12)) == 0x04534e49 /* "\x04SNI" */)
+    {
+      int ret = ndpi_int_sd_rtn_dissect_sni(flow, packet->payload,
+                                                  packet->payload_packet_len);
+
+      if (ret == 0)
+      {
+        ndpi_int_sd_rtn_add_connection(ndpi_struct, flow);
+        return;
+      }
+    }
+  }
+
+  NDPI_EXCLUDE_PROTO(ndpi_struct, flow);
+}
+
+void init_sd_rtn_dissector(struct ndpi_detection_module_struct *ndpi_struct,
+                           u_int32_t *id, NDPI_PROTOCOL_BITMASK *detection_bitmask)
+{
+  ndpi_set_bitmask_protocol_detection("SD-RTN", ndpi_struct, detection_bitmask, *id,
+				      NDPI_PROTOCOL_SD_RTN,
+				      ndpi_search_sd_rtn,
+				      NDPI_SELECTION_BITMASK_PROTOCOL_V4_V6_UDP_WITH_PAYLOAD,
+				      SAVE_DETECTION_BITMASK_AS_UNKNOWN,
+				      ADD_TO_DETECTION_BITMASK);
+
+  *id += 1;
+}
+