My application needs to authenticate a user against active directory and determine the list of groups the user is a member of. I've developed a VB6 app to do this and it works fine.
The customer has come back and said they need the app to authenticate users even if active directory is not available (machine off network), similar to how Windows will still allow a user to log on to a system if a machine is off the network, if they've logged onto the machine previously.
How do I go about accessing the cached user information in VB6? I'm currently user ADI and LDAP.
Related
I'm investigating a failure in my Windows 10 Credential Provider. It calls out to LookupAccountName in order to get the SID of the user that is attempting to log in. Its per-user configuration uses the account SID as the key.
The failure scenario is as follows:
There is a mixture of local and domain accounts on a domain joined computer.
The computer is in an offline or otherwise disconnected state and cannot contact the domain controller.
The domain user has logged in to this computer in the past and its credential is cached.
The call to LookupAccountName fails with ERROR_TRUSTED_RELATIONSHIP_FAILURE (0x6FD)
Here's where things are interesting:
I can log in with a local account and then "Run As" the domain user. Then subsequent calls to LookupAccountName (even when run in the context of the local user) succeeds in looking up the SID of the domain user. It will continue to work until the computer is rebooted.
I've tried calling LookupAccountName as well as LsaLookupNames2. Both exhibit the same behavior. (I assume LookupAccountName is built off of LsaLookupNames2).
It doesn't look like the NetUser* APIs will help me, as I believe they are intended for local accounts.
Is there a way to lookup the account SID for an offline domain credential? Without requiring them to log in first?
Why does using "Run As" cause these APIs to suddenly work?
I need to call WNetGetConnection to get the UNC path and it works good when application run as standard user but it returns 1201(ERROR_CONNECTION_UNAVAIL) error code when application run as admin. According to the documentation its working as expected.
If the network connection was made using the Microsoft LAN Manager
network, and the calling application is running in a different logon
session than the application that made the connection, a call to the
WNetGetConnection function for the associated local device will fail.
The function fails with ERROR_NOT_CONNECTED or
ERROR_CONNECTION_UNAVAIL. This is because a connection made using
Microsoft LAN Manager is visible only to applications running in the
same logon session as the application that made the connection. (To
prevent the call to WNetGetConnection from failing it is not
sufficient for the application to be running in the user account that
created the connection.)
that means its not possible at all to get the UNC path from the app running as admin ? Is there some other way ?
This is by design. Network shares created by a non-elevated account are not visible under elevation, and vice versa.
See this question on Super User for discussion of the issue. There is apparently a registry setting that enables mapped drives to be shared between elevated and non-elevated accounts but I've never tried it myself.
Network connections cannot normally be shared across different Windows login sessions. This is regardless of admin account / elevation level. Each Windows login or impersonation session needs to create its own network connections.
I'm writing a Windows device driver for a custom USB device, but am having trouble opening the device from my user program (using CreateFile) when the user program is run as a domain user. If I run as a local user, or as an administrator (or 'Run As' administrator) I can open the driver fine, but as a domain user GetLastError returns 5 (access denied).
I originally had this problem with local users too, and found I had to add the following SDDL entry to the .inf file, which solved the problem for local users:
HKR,,Security,,"D:P(A;;GA;;;SY)(A;;GA;;;BA)(A;;GRGW;;;BU)
From this reference:
http://msdn.microsoft.com/en-us/library/windows/hardware/ff563667(v=vs.85).aspx
When I discovered that domain users did not have access I thought that simply adding them to this SDDL entry would give them access, but it doesn't seem to work: I still get access denied. I've even tried extreme solutions such as giving all users (everyone (WD), unauthenticated users etc.) full access, but this doesn't work either, which makes me think the problem lies elsewhere; i.e. something else is denying domain users access which takes precedent over the permit in the SDDL entry in the driver inf.
So my question is, what am I missing that is required to give domain users (or all users) access to connect to the driver? Or are there any other solutions to this problem (such as connecting to the driver as a service and then accessing this service from the user program)?
HKR,,Security,,"D:P(A;;GA;;;WD)"
set everyone can access, try it!
Our developers have recently built a new internal 'image viewer' application for our staff to use. The image viewer runs as a website and uses Active Directory to authenticate the user and control what type of images that user is allowed to view.
I have this setup and working fine by running the website as an impersonated domain user. The problem I now face is that all the images are held on a non-domain share. How can I access this share using the domain user? The share is on a Novell Netware 6.5 server.
Alternatively I can run the website as a non-domain user and connect to the Netware server to retrieve the images, but then I am unable to query Active Directory.
Can I allow a non-domain user access to query AD? I don't wish to allow anonymous queries on my domain controllers.
No, a non-domain user cannot query Active Directory unless you configure your domain to allow anonymous queries.
Depending on how everything is setup in the web application, you may be able to insert some code to switch security contexts and impersonate a domain user at the point where the query happens.
I am working on the examination system and need to implement the following scenario:
User ( standard windows user ) completes the exam and then it is saved on the network share.
For security reasons the share does not have permissions for this user account. So I use impersonation API ( LogonUserEx, ImpersonateLoggedOnUser, RevertToSelf).
It all worked fine when the user with which I do the impersonation had admin privileges on the
local computer but the requirements are that it will be standard user.
With standard user the share is not visible. When I log in interactively with this user the share is visible and writable. So I assume that the standard user can not mount share when not logged in interactively. Is this correct? Is there a workaround?
The only time my code runs with elevated privileges is during the setup of the software.
I thought about using WNetAddConnection2 API but I need the share to be mounted to
this "hidden" user profile and not the administrator one that runs the setup.