Add The Elder Scrolls Online support (#2376)

* Add The Elder Scrolls Online support

* Use ndpi_memmem instead of memmem from libc

* Add protocol description

* Change selection bitmask to V4_V6

* Update protocols.rst

3 files changed, 99 insertions, 0 deletions

diff --git a/src/lib/ndpi_content_match.c.inc b/src/lib/ndpi_content_match.c.inc
index 31ecb4b7a..e37d04b5e 100644
--- a/src/lib/ndpi_content_match.c.inc
+++ b/src/lib/ndpi_content_match.c.inc
@@ -1610,6 +1610,7 @@ static ndpi_protocol_match host_match[] =
 
    { "easebar.com",                      "NetEaseGames", NDPI_PROTOCOL_NETEASE_GAMES, NDPI_PROTOCOL_CATEGORY_GAME, NDPI_PROTOCOL_FUN, NDPI_PROTOCOL_DEFAULT_LEVEL },
    { "pathofexile.com",                  "PathofExile", NDPI_PROTOCOL_PATHOFEXILE, NDPI_PROTOCOL_CATEGORY_GAME, NDPI_PROTOCOL_FUN, NDPI_PROTOCOL_DEFAULT_LEVEL },
+   { "elderscrollsonline.com",           "TES_Online", NDPI_PROTOCOL_TESO, NDPI_PROTOCOL_CATEGORY_GAME, NDPI_PROTOCOL_FUN, NDPI_PROTOCOL_DEFAULT_LEVEL },
 
 #ifdef CUSTOM_NDPI_PROTOCOLS
 #include "../../../nDPI-custom/custom_ndpi_content_match_host_match.c.inc"
diff --git a/src/lib/ndpi_main.c b/src/lib/ndpi_main.c
index 67eff0e99..8f9e0c399 100644
--- a/src/lib/ndpi_main.c
+++ b/src/lib/ndpi_main.c
@@ -2292,6 +2292,10 @@ static void ndpi_init_protocol_defaults(struct ndpi_detection_module_struct *ndp
 			  "LoLWildRift", NDPI_PROTOCOL_CATEGORY_GAME,
 			  ndpi_build_default_ports(ports_a, 0, 0, 0, 0, 0) /* TCP */,
 			  ndpi_build_default_ports(ports_b, 0, 0, 0, 0, 0) /* UDP */);
+  ndpi_set_proto_defaults(ndpi_str, 1 /* cleartext */, 0 /* nw proto */, NDPI_PROTOCOL_FUN, NDPI_PROTOCOL_TESO,
+			  "TES_Online", NDPI_PROTOCOL_CATEGORY_GAME,
+			  ndpi_build_default_ports(ports_a, 0, 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"
@@ -6166,6 +6170,9 @@ static int ndpi_callback_init(struct ndpi_detection_module_struct *ndpi_str) {
   /* League of Legends: Wild Rift */
   init_lolwildrift_dissector(ndpi_str, &a);
 
+  /* The Elder Scrolls Online */
+  init_teso_dissector(ndpi_str, &a);
+
 #ifdef CUSTOM_NDPI_PROTOCOLS
 #include "../../../nDPI-custom/custom_ndpi_main_init.c"
 #endif
diff --git a/src/lib/protocols/teso.c b/src/lib/protocols/teso.c
new file mode 100644
index 000000000..89a5ba902
--- /dev/null
+++ b/src/lib/protocols/teso.c
@@ -0,0 +1,91 @@
+/*
+ * teso.c
+ *
+ * The Elder Scrolls Online
+ * 
+ * Copyright (C) 2024 - ntop.org
+ * Copyright (C) 2024 - 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_TESO
+
+#include "ndpi_api.h"
+#include "ndpi_private.h"
+
+static void ndpi_int_teso_add_connection(struct ndpi_detection_module_struct * const ndpi_struct,
+                                         struct ndpi_flow_struct * const flow)
+{
+  NDPI_LOG_INFO(ndpi_struct, "found TES Online\n");
+  ndpi_set_detected_protocol(ndpi_struct, flow, NDPI_PROTOCOL_TESO,
+                             NDPI_PROTOCOL_UNKNOWN, NDPI_CONFIDENCE_DPI);
+}
+
+static void ndpi_search_teso(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 TES Online\n");
+
+  if (packet->payload_packet_len < 600 ||
+      ntohl(get_u_int32_t(packet->payload, 0)) != (u_int32_t)(packet->payload_packet_len-4))
+  {
+    NDPI_EXCLUDE_PROTO(ndpi_struct, flow);
+    return;
+  }
+
+  /*
+   * I'd like to use just memcmp and a couple ifs here, but the offset to 
+   * the string "eso.live" or the 0x8B789C01 byte sequence can be different - 
+   * it varies by the amount of characters in the account name, weather on Mars,
+   * etc.
+   */
+
+  const u_int8_t magic[] = { 0x8B, 0x78, 0x9C, 0x01 };
+
+  if (ndpi_memmem(packet->payload, packet->payload_packet_len, "eso.live",
+      NDPI_STATICSTRING_LEN("eso.live")))
+  {
+    ndpi_int_teso_add_connection(ndpi_struct, flow);
+    return;
+  }
+  else if (ndpi_memmem(packet->payload, packet->payload_packet_len, magic,
+           sizeof(magic)))
+  {
+    ndpi_int_teso_add_connection(ndpi_struct, flow);
+    return;
+  }
+
+  NDPI_EXCLUDE_PROTO(ndpi_struct, flow);
+}
+
+void init_teso_dissector(struct ndpi_detection_module_struct *ndpi_struct, u_int32_t *id)
+{
+  ndpi_set_bitmask_protocol_detection("TES_Online", ndpi_struct, *id,
+              NDPI_PROTOCOL_TESO,
+              ndpi_search_teso,
+              NDPI_SELECTION_BITMASK_PROTOCOL_V4_V6_TCP_WITH_PAYLOAD_WITHOUT_RETRANSMISSION,
+              SAVE_DETECTION_BITMASK_AS_UNKNOWN,
+              ADD_TO_DETECTION_BITMASK);
+
+  *id += 1;
+}