[DoT] Dump data with trunc test with --debug

homer.py

@@ -190,6 +190,12 @@ def validate_hostname(hostname, cert):
         return True
     return False
 
+def dump_data(data, text="data"):
+    pref = ' ' * (len(text) - 4)
+    print(f'{text}: ', data)
+    print(pref, 'hex:', " ".join(format(c, '02x') for c in data))
+    print(pref, 'bin:', " ".join(format(c, '08b') for c in data))
+
 def timeout_connection(signum, frame):
     raise TimeoutConnectionError('Connection timeout')
 
@@ -432,20 +438,24 @@ class ConnectionDoT(Connection):
         self.session.shutdown()
         self.session.close()
 
-    def send_data(self, data):
+    def send_data(self, data, dump=False):
+        if dump:
+            dump_data(data, 'data sent')
         length = len(data)
         self.session.send(length.to_bytes(2, byteorder='big') + data)
 
-    def receive_data(self, request):
+    def receive_data(self, request, dump=False):
         buf = self.session.recv(2)
         request.response_size = int.from_bytes(buf, byteorder='big')
         buf = self.session.recv(request.response_size)
+        if dump:
+            dump_data(buf, 'data recv')
         request.response = dns.message.from_wire(buf)
         request.rcode = True
 
-    def send_and_receive(self, request):
-        self.send_data(request.data)
-        self.receive_data(request)
+    def send_and_receive(self, request, dump=False):
+        self.send_data(request.data, dump=dump)
+        self.receive_data(request, dump=dump)
 
     def do_test(self, qname, qtype=rtype):
         request = RequestDoT(qname, qtype, want_dnssec=dnssec, use_edns=edns)
@@ -549,7 +559,7 @@ class ConnectionDoH(Connection):
         request.ctype = content_type
         self.buffer.close()
 
-    def send_and_receive(self, request):
+    def send_and_receive(self, request, dump=False):
         self.prepare(request)
         self.perform()
         self.receive(request)
@@ -725,7 +735,7 @@ def run_check_trunc(connection):
         request.post = True
     try:
         # 8.8.8.8 replies FORMERR but most DoT servers violently shut down the connection (which is legal)
-        connection.send_and_receive(request)
+        connection.send_and_receive(request, dump=debug)
     except CustomException as e:
         ok = False
         error(e)