handling unauthorized connnections

zk/base.py

@@ -10,17 +10,17 @@ from zk.user import User
 
 
 class ZK(object):
-
     is_connect = False
 
     __data_recv = None
     __sesion_id = 0
     __reply_id = 0
 
-    def __init__(self, ip, port=4370, timeout=60):
+    def __init__(self, ip, port=4370, timeout=60,password=0):
         self.__address = (ip, port)
         self.__sock = socket(AF_INET, SOCK_DGRAM)
         self.__sock.settimeout(timeout)
+        self.__password = password
 
     def __create_header(self, command, command_string, checksum, session_id, reply_id):
         '''
@@ -146,6 +146,11 @@ class ZK(object):
         response_size = 8
 
         cmd_response = self.__send_command(command, command_string, checksum, session_id, reply_id, response_size)
+        self.__sesion_id = unpack('HHHH', self.__data_recv[:8])[2]
+        if cmd_response.get('code') == const.CMD_ACK_UNAUTH:
+            command_string = make_commkey(self.__password, self.__sesion_id)
+            cmd_response = self.__send_command(const.CMD_AUTH, command_string, checksum, self.__sesion_id,
+                                               self.__reply_id, response_size)
         if cmd_response.get('status'):
             self.is_connect = True
             # set the session id
@@ -527,4 +532,40 @@ class ZK(object):
         if cmd_response.get('status'):
             return True
         else:
-            raise ZKErrorResponse("Invalid response")
+            raise ZKErrorResponse("Invalid response")
+
+
+def make_commkey(key, session_id, ticks=50):
+    """take a password and session_id and scramble them to send to the time
+    clock.
+    copied from commpro.c - MakeKey"""
+    key = int(key)
+    session_id = int(session_id)
+    k = 0
+    for i in range(32):
+        if (key & (1 << i)):
+            k = (k << 1 | 1)
+        else:
+            k = k << 1
+    k += session_id
+
+    k = pack(b'I', k)
+    k = unpack(b'BBBB', k)
+    k = pack(
+        b'BBBB',
+        k[0] ^ ord('Z'),
+        k[1] ^ ord('K'),
+        k[2] ^ ord('S'),
+        k[3] ^ ord('O'))
+    k = unpack(b'HH', k)
+    k = pack(b'HH', k[1], k[0])
+
+    B = 0xff & ticks
+    k = unpack(b'BBBB', k)
+    k = pack(
+        b'BBBB',
+        k[0] ^ B,
+        k[1] ^ B,
+        B,
+        k[3] ^ B)
+    return k