Andy, one way to do this is to have your Apache boxes make HTTP socket requests to one of the NT boxes running IIS to GET an ACL-protected page where only authenticated users have access.
So you would do a GET request on the page and fill in the header's "authorization: basic" credentials in base64 format as if you were a browser that had been 401 challenged.
If the page comes back correctly, the credentials were valid. If a status 401 comes back, the credentials were bad.
This would be a pretty cheap, easy way to do it.
Another (more complex) possibility is to create a CGI or ISAPI that runs on one of your NT boxes (I suppose under IIS). Your Apache boxes can make HTTP socket requests, e.g.,
http://ntbox/scripts/verify.dll?
user=joe&password=secret
this could return xml on success:
<verify>OK</verify>
or in the case of an error:
<verify>Account locked</verify>
or whatever. The CGI just needs to do:
::RevertToSelf();
::LogonUser(...)
::ImpersonateToken(...);
in sequence to ensure that the credentials are valid for NT (I think that's what the calls are, it's been a while).
Cheers Dave
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