SESSION_SSL=NEVER

Signed-off-by: Neil Johnson <[email protected]>

Author: najohnsn

tnz/tnz.py

@@ -2118,33 +2118,40 @@ def _proc3270ds(self, b_str, zti=None):
     def _process(self, data):
         """Process host data.
         """
+        self.__log_info("i<< data: %r...", data[:5])
         if data[:2] == b"\xff\xfd":  # IAC DO
             self.__log_info("i<< IAC DO %s", self.__tnon(data[2]))
             opt = data[2]
 
             if data[2] == 40:  # TN3270E
+                self.__log_debug("TN3270E")
                 if self.use_tn3270e:
                     self.send_will(40, buffer=True)
                 else:
                     self.send_wont(40, buffer=True)
 
             elif data[2] == 0:  # TRANSMIT-BINARY
+                self.__log_debug("TRANSMIT-BINARY")
                 if opt not in self.local_will:
                     self.send_will(0, buffer=True)
 
             elif data[2] == 24:  # TERMINAL-TYPE
+                self.__log_debug("TERMINAL-TYPE")
                 if opt not in self.local_will:
                     self.send_will(24, buffer=True)
 
             elif data[2] == 25:  # END-OF-RECORD
+                self.__log_debug("END-OF_RECORD")
                 if opt not in self.local_will:
                     self.send_will(25, buffer=True)
 
                 if opt not in self.local_do:
                     self.send_do(25, buffer=True)
 
             elif data[2] == 46:  # START_TLS
-                if not hasattr(self.__loop, "start_tls"):
+                self.__log_debug("START_TLS")
+                ssl_never = os.environ.get("SESSION_SSL") == "NEVER"
+                if ssl_never or not hasattr(self.__loop, "start_tls"):
                     self._log_warn("START_TLS unsupported.")
                     self._log_warn("Python >= 3.7 required")
                     self.send_wont(data[2], buffer=True)
@@ -2157,6 +2164,7 @@ def _process(self, data):
                     self.send_sub(b"\x2e\x01", buffer=True)
 
             else:
+                self.__log_debug("timing mark?")
                 # e.g. Timing mark (6)
                 self.send_wont(data[2], buffer=True)