[Samba] Authenticating PPTP users against Samba/LDAP

[Mike Brodbelt]

Hi,

I have a few remote user who use a PPTP based VPN. The server is running
PoPToP (http://www.poptop.org/), and a pppd patched to support MPPE/MPPC
for (some) added security. Currently, users authentication information
is stored in plaintext in /etc/ppp/chap-secrets. I'd like to be able to
put users into LDAP, and have ppp authenticate either directly against
LDAP, or against Samba (with an LDAP backend). Any ideas on how I might
go about this? Most of the docs I've seen suggest that you can't use PAM
for authentication with CHAP, so it seems not to be as simple as I might
have hoped.

Disclaimer - I haven't actually tried any of this yet, I'm just trying
to get it clear in my head before I start...

Mike.