py3mschap

First of all I hereby acknowledge this is not my original work. This repo is based on work of jamiesun.net@gmail.com, original repo is

https://github.com/talkincode/pymschap.

Why I decided to fork it and rename it

• I needed python3 pip package
• repo is left without much of care, where I need my own code base with possibility to extend it
• I have quite bad experience with pr->fix->pip cycle flow

What you can expect here

If everything is running ok, probably some more from radius related mechanisms implemented in my simple radius testing mini-server raok. This module will be used there and via pip3 maintained for further improvements.

Original example provided by Jamie

def verify_radius_request(ms_chap_response,authenticator_challenge,username,userpwd,secret,authenticator):
    import six
    from pymschap import mschap, mppe
    result = {}
    if len(ms_chap_response)!=50:
        raise Exception("Invalid MSCHAPV2-Response attribute length")
    # if isinstance(userpwd, six.text_type):
    #     userpwd = userpwd.strip().encode('utf-8')
    
    nt_response = ms_chap_response[26:50]
    peer_challenge = ms_chap_response[2:18]
    nt_resp = mschap.generate_nt_response_mschap2(
        authenticator_challenge,
        peer_challenge,
        username,
        userpwd,
    )
    if nt_resp == nt_response:
        auth_resp = mschap.generate_authenticator_response(
            userpwd,
            nt_response,
            peer_challenge,
            authenticator_challenge,
            username
        )
        result['MS-CHAP2-Success'] = auth_resp
        result['MS-MPPE-Encryption-Policy'] = '\x00\x00\x00\x01'
        result['MS-MPPE-Encryption-Type'] = '\x00\x00\x00\x06'
        mppeSendKey, mppeRecvKey = mppe.mppe_chap2_gen_keys(userpwd, nt_response)
        send_key, recv_key = mppe.gen_radius_encrypt_keys(
            mppeSendKey,
            mppeRecvKey,
            secret,
            authenticator)
        result['MS-MPPE-Send-Key'] = send_key
        result['MS-MPPE-Recv-Key'] = recv_key
    else:
        result['Reply-Message'] = "E=691 R=1 C=%s V=3 M=<password error>" % ('\0' * 32)
        
    return result