[pptp-server] Win2k - pptp encyption problems -- a solution

[Steven Pritchard]

Matthew Drobnak said:
> Therefore, the solution, which also worked for me, is that the 
> 40 bit MPPE encryption protocol CANNOT be enabled. Once it is either
> commented out, the connection works flawlessly. A problem here,
> however. I think the exact opposite is true for out-of-the-box
> win2k... if there's no 40bit available, it will fail negotiations, and
> not be able to connect at all..  Anyone care to test this theory?

My testing seems to indicate that the exact opposite is also true for
Windows 98SE and possibly also ME.  Without "mppe-40" in
/etc/ppp/options, they will connect and negotiate MPPE 128 bit, but
pppd spews messages like these for all traffic:

    Apr  9 11:34:00 ra0 pppd[9521]: rcvd [Compressed data] 90 00 bb 5c a3 2d a7 0d ...
    Apr  9 11:34:04 ra0 pppd[9521]: rcvd [Compressed data] 90 01 c3 1a 0e cb c2 29 ...

No traffic actually goes across the link.  Simply adding "mppe-40" to
/etc/ppp/options makes everything work perfectly.  (The clients still
negotiate MPPE 128 bit.)

This is on 2.4.2 with pptpd 1.1.2, with what I think are all of the
current pppd and kernel patches.  (I'd check to see what all I've
applied, but the box with source is unavailable at the moment thanks
to an office move...)

Steve
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