Telnet Server

All ESP8266 boards running MicroPython.
Official boards are the Adafruit Huzzah and Feather boards.
Target audience: MicroPython users with an ESP8266 board.
User avatar
Roberthh
Posts: 3667
Joined: Sat May 09, 2015 4:13 pm
Location: Rhineland, Europe

Re: Telnet Server

Post by Roberthh » Sun Feb 24, 2019 6:38 am

I did actually not look into the code, but searched in the forum and found the hint here:
viewtopic.php?f=8&t=5868&p=33586&hilit=dupterm#p33586

User avatar
rdagger
Posts: 143
Joined: Tue Feb 28, 2017 6:16 pm
Contact:

Re: Telnet Server

Post by rdagger » Tue Sep 15, 2020 5:26 pm

Are there any MicroPython telnet server libraries that support authentication?

User avatar
MostlyHarmless
Posts: 166
Joined: Thu Nov 21, 2019 6:25 pm
Location: Pennsylvania, USA

Re: Telnet Server

Post by MostlyHarmless » Thu Oct 22, 2020 5:54 pm

rdagger wrote:
Tue Sep 15, 2020 5:26 pm
Are there any MicroPython telnet server libraries that support authentication?
Any sort of password based authentication without an encrypted connection is not going to give you added security on a telnet protocol. You won't be able to perform something like server side provided salt with MD5 hashing. At least not in a convenient way.

That said I am currently trying to write some utility that can perform file transfer (put, get, ls, rm , ...) without requiring any additional components installed other than the utelnetserver. The previously mentioned problem of the dupterm receive ring buffer is really messing things up. Has there been any progress on that? Right now I am working around that by basically chunking up the data into 128 bytes and then waiting for an ACK character to be received back. That slows things down to a great deal as it requires a full network round trip every 128 bytes for what really should be a stream.


Regards, Jan

User avatar
MostlyHarmless
Posts: 166
Joined: Thu Nov 21, 2019 6:25 pm
Location: Pennsylvania, USA

Re: Telnet Server

Post by MostlyHarmless » Thu Oct 22, 2020 6:06 pm

Also I created a pull request for a tiny patch that makes utelnetserver work on an ESP32 running current HEAD again.

https://github.com/cpopp/MicroTelnetServer/pull/5


Regards, Jan

User avatar
rdagger
Posts: 143
Joined: Tue Feb 28, 2017 6:16 pm
Contact:

Re: Telnet Server

Post by rdagger » Thu Oct 22, 2020 6:55 pm

MostlyHarmless wrote:
Thu Oct 22, 2020 5:54 pm
Any sort of password based authentication without an encrypted connection is not going to give you added security on a telnet protocol. You won't be able to perform something like server side provided salt with MD5 hashing. At least not in a convenient way.
I'm just trying to find a telnet server that will work with the Pymakr extension for VS Code. It was created for the Pycom telnet server and requires authentication to connect.

User avatar
MostlyHarmless
Posts: 166
Joined: Thu Nov 21, 2019 6:25 pm
Location: Pennsylvania, USA

Re: Telnet Server

Post by MostlyHarmless » Thu Oct 22, 2020 7:56 pm

rdagger wrote:
Thu Oct 22, 2020 6:55 pm
I'm just trying to find a telnet server that will work with the Pymakr extension for VS Code. It was created for the Pycom telnet server and requires authentication to connect.
Understood.

However, as a general rule of thumb I would always expect the more powerful system to accommodate for the limited capabilities of the weaker one (the microcontroller here). Bloating the service code and firmware of a microcontroller with functionality, expected by some IDE, is the opposite of that.

That said, what is the Micropython telnet library that Pymakr extension is meant to communicate with? Is that available as Open Source with a suitable license?


Regards, Jan

User avatar
rdagger
Posts: 143
Joined: Tue Feb 28, 2017 6:16 pm
Contact:

Re: Telnet Server

Post by rdagger » Thu Oct 22, 2020 10:00 pm

MostlyHarmless wrote:
Thu Oct 22, 2020 7:56 pm
That said, what is the Micropython telnet library that Pymakr extension is meant to communicate with? Is that available as Open Source with a suitable license?
Pymakr is made by Pycom and is designed to work with their boards. I don't have any Pycom boards but I assume the telnet library come built-in to their build of MicroPython just like telnet is also included in the Lobo fork.

User avatar
Roberthh
Posts: 3667
Joined: Sat May 09, 2015 4:13 pm
Location: Rhineland, Europe

Re: Telnet Server

Post by Roberthh » Fri Oct 23, 2020 5:56 am

Telnet and ftp are also included in the CC3200 port (Wipy1) as C code. AFAIK, that port was maintained by Danuel Campora. Pycom resp. Daniel used this code for the Pycom products.

User avatar
MostlyHarmless
Posts: 166
Joined: Thu Nov 21, 2019 6:25 pm
Location: Pennsylvania, USA

Re: Telnet Server

Post by MostlyHarmless » Sat Oct 24, 2020 3:02 am

Roberthh wrote:
Fri Oct 23, 2020 5:56 am
Telnet and ftp are also included in the CC3200 port (Wipy1) as C code. AFAIK, that port was maintained by Danuel Campora. Pycom resp. Daniel used this code for the Pycom products.
Does that mean they have password protected but unencrypted telnet and ftp servers? If so I suggest that people check out how easy it is to use tools like Wireshark.

On a side note I checked out your FTP server and considering the problems, that still exist with the dupterm ring buffer, I switched to cpopp's utelnet and your FTP servers as frozen modules. Your FTP server works flawless with curl (might want to add that to the README), so I can put all the necessary steps to update software on a device into a Makefile and just type "make install". Thanks for all your hard work.


Regards, Jan

User avatar
rdagger
Posts: 143
Joined: Tue Feb 28, 2017 6:16 pm
Contact:

Re: Telnet Server

Post by rdagger » Sat Oct 24, 2020 6:31 am


Post Reply