tools: add certification check

If the server disable the anonymous connection option, it accept a client only if the CA of the client matches the CA of the server.
Else (anonymous connection option enabled), the server accept any request.

Change-Id: I6ff6ec72d6f6452ce50fd8aa35896ff7117be6c0
diff --git a/tools/dnc/dnc.yaml b/tools/dnc/dnc.yaml
index 6e092fa..a107615 100644
--- a/tools/dnc/dnc.yaml
+++ b/tools/dnc/dnc.yaml
@@ -6,4 +6,5 @@
 turn_realm: "ring"
 port: 22
 ip: "127.0.0.1"
-CA: Home/.dhtnet # Change this to the path of the CA directory
+CA: HOME/.dhtnet # Change this to the path of the CA directory
+anonymous: false
\ No newline at end of file