From 69f154d9cc3446d00c2eaad97372414e2e497509 Mon Sep 17 00:00:00 2001
From: Julien Duponchelle <julien@gns3.net>
Date: Tue, 8 Nov 2016 20:10:17 +0100
Subject: [PATCH] Correctly initialize connection to VPCS console

---
 gns3server/compute/base_node.py           |  1 +
 gns3server/utils/asyncio/telnet_server.py | 57 ++++++++++++++---------
 2 files changed, 37 insertions(+), 21 deletions(-)

diff --git a/gns3server/compute/base_node.py b/gns3server/compute/base_node.py
index 8921e7c5..27e0c56f 100644
--- a/gns3server/compute/base_node.py
+++ b/gns3server/compute/base_node.py
@@ -332,6 +332,7 @@ class BaseNode:
         if not self._wrap_console:
             return
         (reader, writer) = yield from asyncio.open_connection(host="127.0.0.1", port=self._internal_console_port)
+        yield from AsyncioTelnetServer.write_client_intro(writer, echo=True)
         server = AsyncioTelnetServer(reader=reader, writer=writer, binary=True, echo=True)
         self._wrapper_telnet_server = yield from asyncio.start_server(server.run, self._manager.port_manager.console_host, self.console)
 
diff --git a/gns3server/utils/asyncio/telnet_server.py b/gns3server/utils/asyncio/telnet_server.py
index fd9afe1b..e1ffc61f 100644
--- a/gns3server/utils/asyncio/telnet_server.py
+++ b/gns3server/utils/asyncio/telnet_server.py
@@ -73,32 +73,48 @@ class AsyncioTelnetServer:
         # it's our job (or the wrapped app) to send back the data
         self._echo = echo
 
+    @staticmethod
+    @asyncio.coroutine
+    def write_client_intro(writer, echo=False):
+        # Send initial telnet session opening
+        if echo:
+            writer.write(bytes([IAC, WILL, ECHO]))
+        else:
+            writer.write(bytes([
+                IAC, WONT, ECHO,
+                IAC, DONT, ECHO]))
+        yield from writer.drain()
+
+    @asyncio.coroutine
+    def _write_intro(self, writer, binary=False, echo=False):
+        # Send initial telnet session opening
+        if echo:
+            writer.write(bytes([IAC, WILL, ECHO]))
+        else:
+            writer.write(bytes([
+                IAC, WONT, ECHO,
+                IAC, DONT, ECHO]))
+
+        if binary:
+            writer.write(bytes([
+                IAC, WILL, SGA,
+                IAC, WILL, BINARY,
+                IAC, DO, BINARY]))
+        else:
+            writer.write(bytes([
+                IAC, WONT, SGA,
+                IAC, DONT, SGA,
+                IAC, WONT, BINARY,
+                IAC, DONT, BINARY]))
+        yield from writer.drain()
+
     @asyncio.coroutine
     def run(self, network_reader, network_writer):
         # Keep track of connected clients
         self._clients.add(network_writer)
 
         try:
-            # Send initial telnet session opening
-            if self._echo:
-                network_writer.write(bytes([IAC, WILL, ECHO]))
-            else:
-                network_writer.write(bytes([
-                                     IAC, WONT, ECHO,
-                                     IAC, DONT, ECHO]))
-
-            if self._binary:
-                network_writer.write(bytes([
-                    IAC, WILL, SGA,
-                    IAC, WILL, BINARY,
-                    IAC, DO, BINARY]))
-            else:
-                network_writer.write(bytes([
-                    IAC, WONT, SGA,
-                    IAC, DONT, SGA,
-                    IAC, WONT, BINARY,
-                    IAC, DONT, BINARY]))
-            yield from network_writer.drain()
+            yield from self._write_intro(network_writer, echo=self._echo, binary=self._binary)
 
             yield from self._process(network_reader, network_writer)
         except ConnectionResetError:
@@ -149,7 +165,6 @@ class AsyncioTelnetServer:
                     return_when=asyncio.FIRST_COMPLETED)
             for coro in done:
                 data = coro.result()
-
                 if coro == network_read:
                     if network_reader.at_eof():
                         raise ConnectionResetError()