Implemented FacebookZero protocol support

https://code.facebook.com/posts/608854979307125/building-zero-protocol-for-fast-secure-mobile-connections/

Discontinued filetopia protocol

1 files changed, 132 insertions, 0 deletions

diff --git a/src/lib/protocols/fbzero.c b/src/lib/protocols/fbzero.c
new file mode 100644
index 000000000..31acd0c9a
--- /dev/null
+++ b/src/lib/protocols/fbzero.c
@@ -0,0 +1,132 @@
+/*
+ * fbzero.c
+ *
+ * Copyright (C) 2018 - 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"
+
+/* https://code.facebook.com/posts/608854979307125/building-zero-protocol-for-fast-secure-mobile-connections/ */
+
+#ifdef NDPI_PROTOCOL_FBZERO
+
+#define NDPI_CURRENT_PROTO NDPI_PROTOCOL_FBZERO
+
+#include "ndpi_api.h"
+
+PACK_ON
+struct fbzero_tag {
+  char tag[4];
+  u_int32_t tag_offset_len;
+} PACK_OFF;
+
+PACK_ON
+struct fbzero_header {
+  u_int8_t flags;
+  char version[3];
+  u_int8_t unknown;
+  u_int32_t len;
+  char tag[4];
+  u_int16_t tag_number, _pad;
+} PACK_OFF;
+
+/* **************************************************************************** */
+
+void ndpi_search_fbzero(struct ndpi_detection_module_struct *ndpi_struct,
+			struct ndpi_flow_struct *flow) {
+  struct ndpi_packet_struct *packet = &flow->packet;
+
+  NDPI_LOG_DBG(ndpi_struct, "search FacebookZero\n");
+
+  if(packet->payload_packet_len > sizeof(struct fbzero_header)) {
+    struct fbzero_header *h = (struct fbzero_header*)packet->payload;
+    struct fbzero_tag *t;
+    u_int offset = sizeof(struct fbzero_header), i, data_offset, tag_number, data_prev_offset = 0;
+
+    if((h->flags & 0x01) == 0)
+      goto fbzero_not_found;
+
+    if((h->version[0] != 'Q')
+       || (h->version[1] != 'T')
+       || (h->version[2] != 'V'))
+      goto fbzero_not_found;
+
+    if(h->unknown != 0x30)
+      goto fbzero_not_found;
+
+    t = (struct fbzero_tag*)&packet->payload[offset];
+    tag_number = h->tag_number;
+    data_offset = offset + tag_number*sizeof(struct fbzero_tag);
+
+    if(strncmp(h->tag, "CHLO", 4))
+      goto fbzero_not_found;
+
+    for(i=0; i<h->tag_number; i++) {
+#ifdef DEBUG
+      printf("[FBZERO] %u) %c%c%c%c\n", i, t->tag[0], t->tag[1], t->tag[2], t->tag[3]);
+#endif
+
+      offset += sizeof(struct fbzero_tag);
+
+      if((t->tag[0] == 'S') && (t->tag[1] == 'N')
+	 && (t->tag[2] == 'I') && (t->tag[3] == '\0')) {
+	char *value = (char*)&packet->payload[data_offset + data_prev_offset];
+	u_int tag_len = t->tag_offset_len-data_prev_offset, max_len;
+
+	max_len = ndpi_min(tag_len, sizeof(flow->host_server_name)-1);
+
+	strncpy((char*)flow->host_server_name, value, max_len);
+	flow->host_server_name[max_len] = '\0';
+
+#ifdef DEBUG
+	printf("[FBZERO] SNI [@%u][len: %u][%s]\n", tag_len,
+	       t->tag_offset_len-data_prev_offset, flow->host_server_name);
+#endif
+
+	ndpi_set_detected_protocol(ndpi_struct, flow, NDPI_PROTOCOL_FBZERO, NDPI_PROTOCOL_UNKNOWN);
+	  
+	ndpi_match_host_subprotocol(ndpi_struct, flow, (char *)flow->host_server_name,
+				    strlen((const char *)flow->host_server_name),
+				    NDPI_PROTOCOL_FBZERO);
+	return;
+      }
+
+      data_prev_offset = t->tag_offset_len;
+      t = (struct fbzero_tag*)&packet->payload[offset];
+    }
+
+    return;
+  }
+
+ fbzero_not_found:
+  NDPI_EXCLUDE_PROTO(ndpi_struct, flow);
+}
+
+/* **************************************************************************** */
+
+void init_fbzero_dissector(struct ndpi_detection_module_struct *ndpi_struct, u_int32_t *id,
+			   NDPI_PROTOCOL_BITMASK *detection_bitmask) {
+  ndpi_set_bitmask_protocol_detection("FacebookZero", ndpi_struct, detection_bitmask, *id,
+				      NDPI_PROTOCOL_FBZERO,
+				      ndpi_search_fbzero,
+				      NDPI_SELECTION_BITMASK_PROTOCOL_V4_V6_TCP_WITH_PAYLOAD_WITHOUT_RETRANSMISSION,
+				      SAVE_DETECTION_BITMASK_AS_UNKNOWN,
+				      ADD_TO_DETECTION_BITMASK);
+  *id += 1;
+}
+
+#endif