cannot retrieve a file in a subdirectory

[GoogleCodeExporter]

What steps will reproduce the problem?
1. mkdir -p A
2. touch A/B
3. start tftp server pointing at directory with A as root dir
4. request file /A/B

What is the expected output? What do you see instead?

I expect to see file B returned. Instead my TFTP client times out. No TFTP 
error codes are returned.


What version of the product are you using? On what operating system?

v3.1 on Linux (Ubuntu 13.04 \n \l)


Please provide any additional information below.

The problem is located in tftp_engine.py at lines 621-628 where the filename is 
checked for valid characters. Unfortunately, '/' is not considered a valid 
character and this is why the filename is silently rejected.

Add this before the test to _escape_ the '/' character.

        temp_filename=temp_filename.replace("/", "x")

Original issue reported on code.google.com by [email protected] on 17 Sep 2013 at 12:15