Fix CONNECT check for reserved=0, as per MQTT v3.1.1 check MQTT-3.1.2-3.

ChangeLog.txt

@@ -13,6 +13,7 @@ Broker:
 - Fix problems with large retained messages over websockets. Closes #427.
 - Set persistence file to only be readable by owner, except on Windows. Closes
   #468.
+- Fix CONNECT check for reserved=0, as per MQTT v3.1.1 check MQTT-3.1.2-3.
 
 Clients:
 - Don't use / in auto-generated client ids.

src/read_handle_server.c

@@ -171,6 +171,13 @@ int mqtt3_handle_connect(struct mosquitto_db *db, struct mosquitto *context)
 		rc = 1;
 		goto handle_connect_error;
 	}
+	if(context->protocol == mosq_p_mqtt311){
+		if((connect_flags & 0x01) != 0x00){
+			rc = MOSQ_ERR_PROTOCOL;
+			goto handle_connect_error;
+		}
+	}
+
 	clean_session = (connect_flags & 0x02) >> 1;
 	will = connect_flags & 0x04;
 	will_qos = (connect_flags & 0x18) >> 3;

test/broker/01-connect-invalid-reserved.py

@@ -0,0 +1,33 @@
+#!/usr/bin/env python
+
+# Test whether a CONNECT with reserved set to 1 results in a disconnect. MQTT-3.1.2-3
+
+import inspect, os, sys
+# From http://stackoverflow.com/questions/279237/python-import-a-module-from-a-folder
+cmd_subfolder = os.path.realpath(os.path.abspath(os.path.join(os.path.split(inspect.getfile( inspect.currentframe() ))[0],"..")))
+if cmd_subfolder not in sys.path:
+    sys.path.insert(0, cmd_subfolder)
+
+import mosq_test
+
+rc = 1
+keepalive = 10
+connect_packet = mosq_test.gen_connect("connect-invalid-test", keepalive=keepalive, connect_reserved=True, proto_ver=4)
+
+cmd = ['../../src/mosquitto', '-p', '1888']
+broker = mosq_test.start_broker(filename=os.path.basename(__file__), cmd=cmd)
+
+try:
+    sock = mosq_test.do_client_connect(connect_packet, "")
+    sock.close()
+    rc = 0
+
+finally:
+    broker.terminate()
+    broker.wait()
+    if rc:
+        (stdo, stde) = broker.communicate()
+        print(stde)
+
+exit(rc)
+

test/broker/Makefile

@@ -20,6 +20,7 @@ test : test-compile 01 02 03 04 05 06 07 08 09 10
 	./01-connect-invalid-id-0.py
 	./01-connect-invalid-id-0-311.py
 	./01-connect-invalid-id-missing.py
+	./01-connect-invalid-reserved.py
 	./01-connect-anon-denied.py
 	./01-connect-uname-no-password-denied.py
 	./01-connect-uname-password-denied.py

test/mosq_test.py

@@ -91,6 +91,19 @@ def remaining_length(packet):
     return (packet, rl)
 
 
+def to_hex_string(packet):
+    if len(packet) == 0:
+        return ""
+
+    s = ""
+    while len(packet) > 0:
+        packet0 = struct.unpack("!B", packet[0])
+        s = s+hex(packet0[0]) + " "
+        packet = packet[1:]
+
+    return s
+
+
 def to_string(packet):
     if len(packet) == 0:
         return ""
@@ -150,6 +163,9 @@ def to_string(packet):
             (password, packet) = struct.unpack(pack_format, packet)
             s = s+", password="+password
 
+        if flags&1:
+            s = s+", reserved=1"
+
         return s
     elif cmd == 0x20:
         # CONNACK
@@ -250,7 +266,7 @@ def to_string(packet):
         # Reserved
         return "0xF0"
 
-def gen_connect(client_id, clean_session=True, keepalive=60, username=None, password=None, will_topic=None, will_qos=0, will_retain=False, will_payload="", proto_ver=3):
+def gen_connect(client_id, clean_session=True, keepalive=60, username=None, password=None, will_topic=None, will_qos=0, will_retain=False, will_payload="", proto_ver=3, connect_reserved=False):
     if (proto_ver&0x7F) == 3 or proto_ver == 0:
         remaining_length = 12
     elif (proto_ver&0x7F) == 4:
@@ -262,6 +278,10 @@ def gen_connect(client_id, clean_session=True, keepalive=60, username=None, pass
         remaining_length = remaining_length + 2+len(client_id)
 
     connect_flags = 0
+
+    if connect_reserved:
+        connect_flags = connect_flags | 0x01
+
     if clean_session:
         connect_flags = connect_flags | 0x02