PAL - a Primitive Authentication Library in C++ for educational purposes

*** GETTING STARTED

git clone git://github.com/olvemaudal/pal.git
cd pal
make  

*** BACKGROUND

This library is being developed primarily to be used for teaching and
discussing C++.

It was originally developed as part of my Solid C++ talk at ACCU 2010,
where the basic idea was to have some well written code doped with
some "negative" issues that the audience to could comment on:

  http://olvemaudal.wordpress.com/2010/04/15/solid-c-code-by-example/

A similar talk was also presented for Oslo C++ Users Group (May 2010):

  http://c.meetup.com/56/calendar/13123479/

and at Norwegian Developer Conference 2010 (June 2010):

  http://www.slideshare.net/olvemaudal/solid-c-by-example

*** USE STORY AND ADDITIONAL REQUIREMENT

Here is the main "use story":

As a client, when prompted for ntlm authentication by the server, I
want a tool/library that can help me to create the initial ntlm
request (type 1 message) that I can send to the server to receive a
challenge (type 2 message) that needs to be solved by applying my
username and password to create an ntlm response that I can send to
the server. (phew...)

Here are some (imaginary) additional requirements:
- must be in C or C++, since embeeded
- it should be possible and convenient to create a <100kb client using
  the PAL library
- must use C++ (due to PHB decision)
- must use nothing but C++ 1998 (due to compiler support, eg tr1 or
  boost can not be used)
- initally the library will only be used to communicate HTTP with 
  a Windows 2003 Server SP2, currently no need to support other servers

*** FILES

Here are the main files (I would like them to be "perfect"): 

  pal.hpp / pal.cpp - the main API to the pal library
  type1_message.[hc]pp - support for ntlm request messages
  type2_message.[hc]pp - support for ntlm challenge messages
  type3_message.[hc]pp - support for ntlm response messages
  Makefile - try 'make all', note OpenSSL is required

here are some supporting files (not so important):

  tools.[hc]pp - tools that might be provided by the executing platform
  ntlm_ssp_flags.hpp - useful constants for working with ssp flags
  httpget.cpp - a demo client, see for example of how to use the PAL library
  tests.cpp - some "high-level" unit tests
  dope.txt - examples of "bad" things you can introduce for educational use
  notes.txt - a scratch pad used during development

*** ISSUES

The code is currently under construction, there are still things that
needs attention:

- the current API into PAL sucks big time, needs improvement
- some of the funtions in tools.[hc]pp needs to be improved to support
  the actual usage. Here tools.[hc]pp might use OpenSSL, but there is
  an underlying assumption that in real use the implementation of
  tools might use platform supported functionality instead.
- this README file needs some attention, perhaps an explaination of
  the NTLM authentication protocol would be useful?
- the use of stdint.h in C++98 code is questionable...

*** COPYRIGHT ISSUES

This code was originally developed by Olve Maudal, but I have had
lots of help from a number of people. You know who you are, thanks!

Feel free to copy/derive/modify/use/misuse this code for whatever you
want.

Derived work and forking of this project is very much encouraged. Or
you may contribute by sending patches. Please help to improve the code
as far as possible, as long as the focus on educational value is
maintained.