Add EDNS0 support and update docs

README.md

@@ -81,13 +81,13 @@ it to your actual network traceroute and make sure your DNS traffic is not
 routed to any unwanted path.
 
 ```
-% ./dnstraceroute.py --expert -t A -s 8.8.4.4 facebook.com
+% ./dnstraceroute.py --expert -C -e -t A -s 8.8.4.4 facebook.com
 dnstraceroute.py DNS: 8.8.4.4:53, hostname: facebook.com, rdatatype: A
-1	192.168.0.1 (192.168.0.1) 2 ms
+1	192.168.0.1 (192.168.0.1) 1 ms
-2	192.168.28.177 (192.168.28.177) 11 ms
+2	192.168.28.177 (192.168.28.177) 4 ms
-3	 *
+3	192.168.0.1 (192.168.0.1) 693 ms
-4	172.19.4.17 (172.19.4.17) 7 ms
+4	172.19.4.17 (172.19.4.17) 3 ms
-5	google-public-dns-b.google.com (8.8.4.4) 14 ms
+5	google-public-dns-b.google.com (8.8.4.4) 8 ms
 
 === Expert Hints ===
  [*] public DNS server is next to a private IP address (possible hijacking)

dnsping.py

@@ -59,6 +59,7 @@ usage: %s [-h] [-q] [-v] [-s server] [-p port] [-P port] [-S address] [-c count]
   -c  --count     Number of requests to send (default: 10)
   -w  --wait      Maximum wait time for a reply (default: 5)
   -t  --type      DNS request record type (default: A)
+  -e  --edns      Use EDNS0
 """ % (__PROGNAME__, __VERSION__, __PROGNAME__))
     sys.exit(0)
 

dnstraceroute.py

@@ -117,7 +117,7 @@ except IOError:
 
 def usage():
     print('%s version %1.1f\n' % (__PROGNAME__, __version__))
-    print('usage: %s [-h] [-q] [-a] [-s server] [-p port] [-c count] [-t type] [-w wait] hostname' % __PROGNAME__)
+    print('usage: %s [-aeqhC] [-s server] [-p port] [-c count] [-t type] [-w wait]  hostname' % __PROGNAME__)
     print('  -h  --help      Show this help')
     print('  -q  --quiet     Quiet')
     print('  -e  --expert    Print expert hints if available')
@@ -128,6 +128,7 @@ def usage():
     print('  -w  --wait      Maximum wait time for a reply (default: 5)')
     print('  -t  --type      DNS request record type (default: A)')
     print('  -C  --color     Print colorful output')
+    print('  -e  --edns      Use EDNS0')
     print('  ')
     sys.exit()
 
@@ -171,13 +172,16 @@ def expert_report(trace_path, color_mode):
     print(" %s[*]%s No expert hint available for this trace" % (color.G, color.N))
 
 
-def ping(resolver, hostname, dnsrecord, ttl):
+def ping(resolver, hostname, dnsrecord, ttl, use_edns= False):
     global _ttl
 
     reached = False
 
     dns.query.socket_factory = CustomSocket
     _ttl = ttl
+    if use_edns:
+        resolver.use_edns(edns=0, payload=8192, ednsflags=dns.flags.edns_from_text('DO'))
+
 
     try:
         resolver.query(hostname, dnsrecord, raise_on_no_answer=False)
@@ -228,6 +232,7 @@ def main():
     as_lookup = False
     expert_mode = False
     should_resolve = True
+    use_edns = False
     color_mode = False
 
     try:
@@ -267,6 +272,8 @@ def main():
             should_resolve = False
         elif o in ("-a", "--asn"):
             as_lookup = True
+        elif o in ("-e", "--edns"):
+            use_edns = True
         else:
             usage()
 
@@ -321,7 +328,7 @@ def main():
 
         with concurrent.futures.ThreadPoolExecutor(max_workers=1) as pool:  # dispatch dns lookup to another thread
             stime = time.time()
-            thr = pool.submit(ping, resolver, hostname, dnsrecord, ttl)
+            thr = pool.submit(ping, resolver, hostname, dnsrecord, ttl, use_edns=use_edns)
 
             try:  # expect ICMP response
                 _, curr_addr = icmp_socket.recvfrom(512)
@@ -338,7 +345,7 @@ def main():
         if reached:
             curr_addr = dnsserver
             stime = time.time()  # need to recalculate elapsed time for last hop without waiting for an icmp error reply
-            ping(resolver, hostname, dnsrecord, ttl)
+            ping(resolver, hostname, dnsrecord, ttl, use_edns=use_edns)
             etime = time.time()
 
         elapsed = abs(etime - stime) * 1000  # convert to milliseconds