Using EDNS0 is now optional and disabled by default

Also update documentation with new example

README.md

@@ -107,17 +107,21 @@ dnseval is a bulk ping utility that sends an arbitrary DNS query to a give list
 of DNS servers. This script is meant for comparing response time of multiple
 DNS servers at once:
 ```
-% ./dnseval.py -f public-v4.txt -c3 ripe.net
+% ./dnseval.py -e -t AAAA -f public-v4.txt -c10 fg.weberdns.de
-server           avg(ms)     min(ms)     max(ms)     stddev(ms)  lost(%)  flags
+server           avg(ms)     min(ms)     max(ms)     stddev(ms)  lost(%)    flags
-----------------------------------------------------------------------------------
+────────────────────────────────────────────────────────────────────────────────────────────────
-8.8.8.8          210.225     109.864     407.420     170.785     %0       QR RD RA
+8.8.8.8          94.556      90.488      112.209     6.322       %0         QR -- -- RD RA AD --
-8.8.4.4          107.850     93.134      120.578     13.830      %0       QR RD RA
+8.8.4.4          92.599      90.265      94.338      1.086       %0         QR -- -- RD RA AD --
-ns.ripe.net      118.911     114.874     123.389     4.275       %0       QR AA RD
+ns.ripe.net      92.754      91.632      93.980      0.900       %0         QR -- -- RD RA AD --
-4.2.2.1          104.380     102.449     106.588     2.083       %0       QR RD RA
+4.2.2.1          92.703      91.869      93.298      0.482       %0         QR -- -- RD RA AD --
-4.2.2.2          131.056     99.143      193.711     54.264      %0       QR RD RA
+4.2.2.2          93.195      91.667      94.919      1.065       %0         QR -- -- RD RA AD --
-4.2.2.3          98.956      97.463      100.310     1.429       %0       QR RD RA
+4.2.2.3          93.118      92.076      94.835      0.835       %0         QR -- -- RD RA AD --
-4.2.2.4          223.173     97.418      463.728     208.398     %0       QR RD RA
+4.2.2.4          94.308      92.175      103.318     3.261       %0         QR -- -- RD RA AD --
-4.2.2.5          104.290     97.264      117.878     11.770      %0       QR RD RA
+4.2.2.5          92.650      91.643      94.460      1.002       %0         QR -- -- RD RA AD --
+209.244.0.3      92.810      89.961      94.807      1.266       %0         QR -- -- RD RA AD --
+209.244.0.4      93.127      91.962      95.970      1.227       %0         QR -- -- RD RA AD --
+195.46.39.39     92.770      90.777      93.656      0.914       %0         QR -- -- RD RA AD --
+195.46.39.40     92.903      91.280      94.914      1.147       %0         QR -- -- RD RA AD --
 ```
 
 ### Author

dnseval.py

@@ -54,6 +54,7 @@ usage: %s [-h] [-f server-list] [-c count] [-t type] [-w wait] hostname
   -w  --wait      maximum wait time for a reply (default: 5)
   -t  --type      DNS request record type (default: A)
   -T  --tcp       Use TCP instead of UDP
+  -e  --edns      Use EDNS0
 """ % (__PROGNAME__, __VERSION__, __PROGNAME__))
     sys.exit()
 
@@ -115,7 +116,7 @@ def flags_to_text(flags):
     return ' '.join(text_flags)
 
 
-def dnsping(host, server, dnsrecord, timeout, count, use_tcp=False):
+def dnsping(host, server, dnsrecord, timeout, count, use_tcp=False, use_edns=False):
     resolver = dns.resolver.Resolver()
     resolver.nameservers = [server]
     resolver.timeout = timeout
@@ -123,7 +124,8 @@ def dnsping(host, server, dnsrecord, timeout, count, use_tcp=False):
     resolver.retry_servfail = 0
     flags = 0
     answers = None
-    resolver.use_edns(edns=0, payload=4096, ednsflags=dns.flags.edns_from_text('DO'))
+    if use_edns:
+        resolver.use_edns(edns=0, payload=8192, ednsflags=dns.flags.edns_from_text('DO'))
 
     response_times = []
     i = 0
@@ -133,7 +135,8 @@ def dnsping(host, server, dnsrecord, timeout, count, use_tcp=False):
             break
         try:
             stime = time.time()
-            answers = resolver.query(host, dnsrecord, tcp=use_tcp, raise_on_no_answer=False)  # todo: response validation in future
+            answers = resolver.query(host, dnsrecord, tcp=use_tcp,
+                                     raise_on_no_answer=False)  # todo: response validation in future
             etime = time.time()
         except (dns.resolver.NoNameservers, dns.resolver.NoAnswer):
             break
@@ -184,11 +187,12 @@ def main():
     inputfilename = None
     fromfile = False
     use_tcp = False
+    use_edns = False
     hostname = 'wikipedia.org'
 
     try:
-        opts, args = getopt.getopt(sys.argv[1:], "hf:c:t:w:T",
+        opts, args = getopt.getopt(sys.argv[1:], "hf:c:t:w:Te",
-                                   ["help", "file=", "count=", "type=", "wait=", "tcp"])
+                                   ["help", "file=", "count=", "type=", "wait=", "tcp", "edns"])
     except getopt.GetoptError as err:
         print(err)
         usage()
@@ -212,6 +216,8 @@ def main():
             dnsrecord = a
         elif o in ("-T", "--tcp"):
             use_tcp = True
+        elif o in ("-e", "--edns"):
+            use_edns = True
         else:
             print("Invalid option: %s" % o)
             usage()
@@ -251,7 +257,8 @@ def main():
             if not s:
                 continue
             (s, r_avg, r_min, r_max, r_stddev, r_lost_percent, flags) = dnsping(hostname, s, dnsrecord, waittime,
-                                                                                count, use_tcp=use_tcp)
+                                                                                count, use_tcp=use_tcp,
+                                                                                use_edns=use_edns)
 
             s = server.ljust(width + 1)
             text_flags = flags_to_text(flags)

requirements.txt

@@ -0,0 +1 @@
+dnspython==1.15.0