telnet: add disabled code to emit EC and IP

> I'm trying to connect to a Korenix 3005 switch through telnet
> for management purposes, and all is well except for the backspace character
> - seems like my switch doesn't handle it too well and instead of erasing
> the last character all it does is print some garbage to the screen.
> I've had the same issue before while using putty, but saw a solution that
> suggests to enable "Telnet special commands" in the options menu, and it
> worked.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/networking/telnet.c b/networking/telnet.c
index 5c8805265..9fc85050b 100644
--- a/networking/telnet.c
+++ b/networking/telnet.c
@@ -238,6 +238,18 @@ static void handle_net_output(int len)
                         *dst = '\r'; /* Enter -> CR LF */
                         *++dst = '\n';
                 }
+#if 0
+/* putty's "special commands" mode does this: */
+/* Korenix 3005 switch needs at least the backspace tweak */
+                if (c == 0x08 || c == 0x7f) { /* ctrl+h || backspace */
+                        *dst = IAC;
+                        *++dst = EC;
+                }
+                if (c == 0x03) { /* ctrl+c */
+                        *dst = IAC;
+                        *++dst = IP;
+                }
+#endif
                 dst++;
         }
         if (dst - outbuf != 0)