Added tinc protocol detection

1 files changed, 160 insertions, 0 deletions

diff --git a/src/lib/protocols/tinc.c b/src/lib/protocols/tinc.c
new file mode 100644
index 000000000..b25aff2e7
--- /dev/null
+++ b/src/lib/protocols/tinc.c
@@ -0,0 +1,160 @@
+/*
+ * tinc.c
+ *
+ * Copyright (C) 2017 - William Guglielmo <william@deselmo.com>
+ * Copyright (C) 2017 - 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_api.h"
+
+#ifdef NDPI_PROTOCOL_TINC
+
+static void ndpi_check_tinc(struct ndpi_detection_module_struct *ndpi_struct, struct ndpi_flow_struct *flow)
+{
+  struct ndpi_packet_struct *packet = &flow->packet;
+  const u_int8_t *packet_payload = packet->payload;
+  u_int32_t payload_len = packet->payload_packet_len;
+  struct ndpi_id_struct *src = flow->src;
+  struct ndpi_id_struct *dst = flow->dst;
+  
+  if(packet->udp != NULL) {
+    if(ndpi_struct->tinc_cache != NULL) {
+      tinc_cache_entry_t tinc_cache_entry1 = {
+        .src_address = packet->iph->saddr,
+        .dst_address = packet->iph->daddr,
+        .dst_port = packet->udp->dest
+      };
+
+      tinc_cache_entry_t tinc_cache_entry2 = {
+        .src_address = packet->iph->daddr,
+        .dst_address = packet->iph->saddr,
+        .dst_port = packet->udp->source
+      };
+
+      if( cache_remove(ndpi_struct->tinc_cache, &tinc_cache_entry1, sizeof(tinc_cache_entry1)) == CACHE_NO_ERROR ||
+          cache_remove(ndpi_struct->tinc_cache, &tinc_cache_entry2, sizeof(tinc_cache_entry2)) == CACHE_NO_ERROR)
+      {
+        cache_remove(ndpi_struct->tinc_cache, &tinc_cache_entry1, sizeof(tinc_cache_entry1));
+        cache_remove(ndpi_struct->tinc_cache, &tinc_cache_entry2, sizeof(tinc_cache_entry2));
+
+        // cache_free(ndpi_struct->tinc_cache);
+
+        NDPI_LOG(NDPI_PROTOCOL_TINC, ndpi_struct, NDPI_LOG_DEBUG, "Found tinc udp connection\n");
+        ndpi_set_detected_protocol(ndpi_struct, flow, NDPI_PROTOCOL_TINC, NDPI_PROTOCOL_UNKNOWN);
+      }
+    }
+
+    return;
+
+  } 
+  else if(packet->tcp != NULL) {
+
+    if(payload_len == 0) {
+      if(packet->tcp->syn == 1 && packet->tcp->ack == 0) {
+        flow->tinc_cache_entry.src_address = packet->iph->saddr;
+        flow->tinc_cache_entry.dst_address = packet->iph->daddr;
+        flow->tinc_cache_entry.dst_port = packet->tcp->dest;
+      }
+      return;
+    }
+
+    switch(flow->tinc_state) {
+      case 0:
+      case 1:
+        if(payload_len > 6 && memcmp(packet_payload, "0 ", 2) == 0 && packet_payload[2] != ' ') {
+          u_int16_t i = 3;
+          while(i < payload_len && packet_payload[i++] != ' ');
+          if(i+3 == payload_len && memcmp((packet_payload+i), "17\n", 3) == 0) {
+            flow->tinc_state++;
+            return;
+          }
+        }
+        break;
+
+      case 2:
+      case 3:
+        if(payload_len > 11 && memcmp(packet_payload, "1 ", 2) == 0 && packet_payload[2] != ' ') {
+          u_int16_t i = 3;
+          u_int8_t numbers_left = 4;
+          while(numbers_left) {
+            while(packet_payload[i] >= '0' && packet_payload[i] <= '9') {
+              i++;
+            }
+
+            if(packet_payload[i++] == ' ') {
+              numbers_left--;
+            }
+            else break;
+          }
+          
+          if(numbers_left) break;
+          
+          while((packet_payload[i] >= '0' && packet_payload[i] <= '9') ||
+                (packet_payload[i] >= 'A' && packet_payload[i] <= 'Z')) {
+            i++;
+          }
+          
+          if(packet_payload[i] == '\n') {
+            if(++flow->tinc_state > 3) {
+              if(ndpi_struct->tinc_cache == NULL) {
+                ndpi_struct->tinc_cache = cache_new(TINC_CACHE_MAX_SIZE);
+              }
+
+              cache_add(ndpi_struct->tinc_cache, &(flow->tinc_cache_entry), sizeof(flow->tinc_cache_entry));
+
+              NDPI_LOG(NDPI_PROTOCOL_TINC, ndpi_struct, NDPI_LOG_DEBUG, "Found tinc tcp connection\n");
+              ndpi_set_detected_protocol(ndpi_struct, flow, NDPI_PROTOCOL_TINC, NDPI_PROTOCOL_UNKNOWN);
+            }
+            return;
+          }
+        }
+        break;
+      
+      default: break;
+    }
+  }
+
+  NDPI_LOG(NDPI_PROTOCOL_TINC, ndpi_struct, NDPI_LOG_DEBUG, "exclude tinc.\n");
+  NDPI_ADD_PROTOCOL_TO_BITMASK(flow->excluded_protocol_bitmask, NDPI_PROTOCOL_TINC);
+}
+
+void ndpi_search_tinc(struct ndpi_detection_module_struct* ndpi_struct, struct ndpi_flow_struct* flow) {
+  struct ndpi_packet_struct* packet = &flow->packet;
+
+  NDPI_LOG(NDPI_PROTOCOL_TINC, ndpi_struct, NDPI_LOG_DEBUG, "tinc detection...\n");
+
+  if (packet->detected_protocol_stack[0] != NDPI_PROTOCOL_TINC) {
+    if (packet->tcp_retransmission == 0) {
+      ndpi_check_tinc(ndpi_struct, flow);
+    }
+  }
+}
+
+void init_tinc_dissector(struct ndpi_detection_module_struct *ndpi_struct, u_int32_t *id, NDPI_PROTOCOL_BITMASK *detection_bitmask)
+{
+  ndpi_set_bitmask_protocol_detection("TINC", ndpi_struct, detection_bitmask, *id,
+              NDPI_PROTOCOL_TINC,
+              ndpi_search_tinc,
+              NDPI_SELECTION_BITMASK_PROTOCOL_TCP_OR_UDP,
+              SAVE_DETECTION_BITMASK_AS_UNKNOWN,
+              ADD_TO_DETECTION_BITMASK);
+
+  *id += 1;
+}
+
+#endif