telnet-file-copy

This is a simple utility to copy files onto a linux host running a telnet server, where other means
aren't available. This tool should only be used as a last resort - it's slow, and offers no
integrity guarantees.

On the remote end, all that's necessary is an echo command which supports the -e and -n flags.
If the host has an appropriate shell, and any of md5sum, sha256sum or sha512sum, the most
preferable will be used to verify the integrity of the transfer, and if base64 is present, this
will be used for the transfer instead of echo.