wpaspy: Convert to/from str to bytes as needed for python3

The control interface commands use mostly ASCII or UTF-8 strings, so
convert input/output to strings/bytes as needed for the socket
operations with python3.

Signed-off-by: Jouni Malinen <j@w1.fi>

wpaspy/wpaspy.py

@@ -52,7 +52,7 @@ class Ctrl:
                     break
                 self.s = socket.socket(af, socktype)
                 self.s.settimeout(5)
-                self.s.sendto("GET_COOKIE", sockaddr)
+                self.s.sendto(b"GET_COOKIE", sockaddr)
                 reply, server = self.s.recvfrom(4096)
                 self.cookie = reply
                 self.port = port
@@ -81,13 +81,24 @@ class Ctrl:
             self.started = False
 
     def request(self, cmd, timeout=10):
+        if type(cmd) == str:
+            try:
+                cmd2 = cmd.encode()
+                cmd = cmd2
+            except UnicodeDecodeError as e:
+                pass
         if self.udp:
             self.s.sendto(self.cookie + cmd, self.sockaddr)
         else:
             self.s.send(cmd)
         [r, w, e] = select.select([self.s], [], [], timeout)
         if r:
-            return self.s.recv(4096)
+            res = self.s.recv(4096).decode()
+            try:
+                r = str(res)
+            except UnicodeDecodeError as e:
+                r = res
+            return r
         raise Exception("Timeout on waiting response")
 
     def attach(self):
@@ -127,5 +138,9 @@ class Ctrl:
         return False
 
     def recv(self):
-        res = self.s.recv(4096)
-        return res
+        res = self.s.recv(4096).decode()
+        try:
+            r = str(res)
+        except UnicodeDecodeError as e:
+            r = res
+        return r