From e24b1ebc1eae2bfead771cb5e0e6d715d6dce262 Mon Sep 17 00:00:00 2001
From: nijenhofm <marcel.nijenhof@rws.nl>
Date: Mon, 27 Jul 2020 10:52:04 +0200
Subject: [PATCH] Clear telnet patch voor rdl achter sommige N-porten die
 reverse telnet gebruiken

---
 lmwsip.py | 43 ++++++++++++++++++++++++++++++-------------
 siprun    |  5 ++++-
 2 files changed, 34 insertions(+), 14 deletions(-)

diff --git a/lmwsip.py b/lmwsip.py
index c44802e..a1e04b2 100644
--- a/lmwsip.py
+++ b/lmwsip.py
@@ -28,7 +28,7 @@ Support for:
 
     def __init__(self, user=None, password=None,
             host="sip-lmw.rws.nl", port=443, meetnet="LMW", ssl = True,
-            check_ssl = True, timeout = 10, log = None):
+            check_ssl = True, timeout = 10, log = None, cleartelnet = False):
         """LmwSip(user, password, [host], [port], [meetnet], [ssl], [check_ssl], [timeout], [log])
 
 user(optinal): Lmw user name
@@ -40,6 +40,7 @@ ssl(optional): Default true
 check_ssl(optional): true
 timeout(optional): 10
 log(optional): None
+cleartelnet: False
 
 Opens the connection and logs in
 """
@@ -52,6 +53,7 @@ Opens the connection and logs in
         self.check_ssl   = check_ssl
         self.timeout     = timeout
         self._socket     = None
+        self.cleartelnet = cleartelnet
         if (log != None):
             self.log = log
             self.log.debug("LmwSip.init")
@@ -156,28 +158,32 @@ send a sip command to the server
 
 recieve a answer from the sip server
 """
-        buf=""
+        stringbuf=""
         while self._socket != None and re.search("\r$", buf) == None:
             try:
                 self.log.debug("LmwSip.recv: Waiting for data");
-                b = self._socket.recv(4096).decode('utf-8')
-                if (b == ""):
-                    self.log.error("SipLmw.recv: socket closed")
-                    self.closesocket()
-                    raise LmwSipConnectError("LmwSip.recv: Socket close")
-                else:
-                    buf += b
+                bytebuf = self._socket.recv(4096)
+                if self.cleartelnet:
+                    while bytebuf[0] == '\xff':
+                        self.log.info("SipLmw.recv: telnet data: %s", bytebuf)
+                        bytebuf = self._socket.recv(4096)
             except Exception as e:
                 self.log.error("SipLmw.recv: socket timeout: %s", e)
                 self.closesocket()
                 raise LmwSipConnectError("LmwSip.recv: Socket timeout")
+            try:
+                stringbuf += bytebuf.decode('utf-8')
+            except Exception as e:
+                self.log.error("SipLmw.recv: decode error: %s", e)
+                self.closesocket()
+                raise LmwSipDecodeError("LmwSip.recv: decode error", bytebuf)
         if self._socket == None:
             self.log.warn("LmwSip.recv: No connection")
-        elif buf[0] != '!':
-            self.log.warn("LmwSip.recv: Sip error: %s" % buf.strip('\r'))
+        elif stringbuf[0] != '!':
+            self.log.warn("LmwSip.recv: Sip error: %s" % stringbuf.strip('\r'))
         else:
-            self.log.debug("LmwSip.recv: result: %s" % buf.strip('\r'))
-        return(buf)
+            self.log.debug("LmwSip.recv: result: %s" % stringbuf.strip('\r'))
+        return(stringbuf)
 
     def login(self):
         """login()
@@ -420,6 +426,17 @@ class LmwSipConnectError(Exception):
     def __str__(self):
         return(self.message)
 
+class LmwSipDecodeError(Exception):
+    """Connection exceptions for LmwSip"""
+
+    def __init__(self, message, buf):
+        self.message = message
+        self.buf     = buf
+
+    def __str__(self):
+        return(self.message + ":" + buf)
+
+
 class LmwLoginFailure(Exception):
     """Exception from LmwSip on login failure"""
 
diff --git a/siprun b/siprun
index d41a828..fe15312 100755
--- a/siprun
+++ b/siprun
@@ -10,6 +10,8 @@ def main():
     parser = argparse.ArgumentParser(description="Run a sip file.")
     parser.add_argument("-u", "--unencrypted", action="store_true",
                         help="Run a sip connection without ssl")
+    parser.add_argument("-c", "--cleartelnet", action="store_true",
+                        help="Clear telnet protocol in tcp session")
     parser.add_argument("-H", "--host", action='store',
                         default="sip-lmw.rws.nl",
                         help="Host to connect to")
@@ -27,7 +29,8 @@ def main():
 
     try:
         lmwsip = LmwSip(host=args.host, port=args.port,
-                        ssl=not args.unencrypted)
+                        ssl=not args.unencrypted,
+                        cleartelnet=args.cleartelnet)
     except Exception as e:
         print("Connect to lmw failed: %s" % e)
         exit(1)