Trying to check the friendly OS name of a different workstation - c#

I am trying to find the friendly OS name of a different workstation from my workstation. This occurred when I used:
var name = (from x in new ManagementObjectSearcher("SELECT Caption FROM Win32_OperatingSystem").Get().Cast<ManagementObject>()
select x.GetPropertyValue("Caption")).FirstOrDefault();
it is returning my workstation's OS name. Can you please suggest me a better way to find out.
Thanks in advance!!

You can use the System.DirectoryServices to search on the directory 'WinNT' you can read more about it here:
https://learn.microsoft.com/en-us/dotnet/api/system.directoryservices.directoryentry.path?view=netframework-4.7.2
example solution - adding names to a list
// create list to add the names to
var pcnames = new List<string>();
// establish the domains in the local network
var directory = new DirectoryEntry("WinNT:");
// iterate through the children
foreach (DirectoryEntry workstation in directory.Children)
{
pcnames.Add(workstation.Name)
}

Related

Search Active Directory without using LDAP

I am using C# in VS2008 in a WinXP/Win7/WinServer2003 environment.
Is there a way to search the active directory without involving LDAP?
I have users created in Active Directory but when I search using this
DirectorySearcher dirSearcher = new DirectorySearcher(
new DirectoryEntry("LDAP://DC=kmmnet,DC=com"),
"(objectClass=user)",
new string[] { "sAMAccountName", "displayname", "givenname", "sn" });
foreach (SearchResult s in dirSearcher.FindAll())
{
System.DirectoryServices.PropertyCollection p = s.GetDirectoryEntry().Properties;
}
it cannot find some of the users.
thanks
Shawn
Try bumping the PageSize attribute up from its default of zero:
dirSearcher.PageSize = 9000;
Any non-zero value for PageSize will cause paging to occur, so that you will receive all results (in batches equal to the PageSize).
You can also try filtering the search more (e.g., exclude inactive users, etc.).
And, there is an upper limit on the number of results which a directory server will return in response to an LDAP query. This limit is controlled and set by an administrator on the domain. I believe the default is 1000.

Convert SID's to usernames/groups?

I'm looping through a network directory and trying to output the user/group names (permissions) associated with each file/folder. I'm getting the SID's back but I want the names like "group_test" and not "S-1-5-32-544". Here's my code -
var files = Directory.GetFiles(path, "*.*", SearchOption.TopDirectoryOnly);
foreach (var f in files2)
{
var fileInfo = new FileInfo(f);
var fs = fileInfo.GetAccessControl(AccessControlSections.Access);
foreach (FileSystemAccessRule rule in fs.GetAccessRules(true, true, typeof(System.Security.Principal.NTAccount)))
{
var value = rule.IdentityReference.Value;
Response.Write(string.Format("File: {0} \t Usergroup: {1} <br/>", fileInfo.Name, value));
} }
I get SID's from the above code but in the foreach loop, if I use this instead -
(NTAccount)((SecurityIdentifier)rule.IdentityReference).Translate(typeof(NTAccount)).Value
I get this exception -
Some or all identity references could not be translated.
It appears that the Translate method does not work on remote shares. How do I retrieve the real names of the SID's? The remote server does not have LDAP.
Thank you.
The problem is that you are trying to resolve a SID that is local to a remote machine. As the answer to this question states:
The SecurityReference object's Translate method does work on non-local SIDs but only for domain accounts...
This link provides an example for remotely resolving a SID using WMI which is probably the best method for accomplishing your task.
If you can use WMI you should be able to do it via the Win32_UserAccount class I think. It has a Name property and a SID property.
Or the Win32_Group class for the groups.
Here's an article for connecting to a remote pc using WMI that has C# code: How To: Connect to a Remote Computer

Getting the current logged in user (FullToken Context)

I have a Problem, which is... i start a programm with right click -> run as administrator.
Which means the programm is running in an administrative context.
WindowsIdentity.GetCurrent().Name;
if i try to get the user name that way i will get the user that started the programm as admin.. for example "administrator", but what i need is the name of the current logged in user which is for example: bob
Can anybody help me out? :)
You could try using WMI (System.Management.dll) to get the owner of the explorer.exe process.
string GetExplorerUser()
{
var query = new ObjectQuery(
"SELECT * FROM Win32_Process WHERE Name = 'explorer.exe'");
var explorerProcesses = new ManagementObjectSearcher(query).Get();
foreach (ManagementObject mo in explorerProcesses)
{
string[] ownerInfo = new string[2];
mo.InvokeMethod("GetOwner", (object[])ownerInfo);
return String.Concat(ownerInfo[1], #"\", ownerInfo[0]);
}
return string.Empty;
}
This relies on the fact that the explorer process is single instance an so you don't end up with the possibility of having several explorer processes running with different user credentials.
You will probably need to use win32 API for that. Read about Window Station and Desktop functions here: http://msdn.microsoft.com/en-us/library/ms687107%28v=vs.85%29.aspx
Also see this question:
Get the logged in Windows user name associated with a desktop
Maybe you could start as normal user, save user name, then programmatically request elevation :
Windows 7 and Vista UAC - Programmatically requesting elevation in C#
All .NET libraries will give you the user from the current context ('Administrator' in your case).
If you are trying to secure your code, you might consider reading about: Security in the .NET framework
1) Cassia should be able to give you a list of currently logged in users including RDC.
foreach (ITerminalServicesSession sess in new TerminalServicesManager().GetSessions())
{
// sess.SessionId
// sess.UserName
}
2) WMI (SO answer)
Select * from Win32_LogonSession
3) PInvoke to WTSEnumerateSessions
4) Enumerate all instances of "explorer.exe" and get the owner using PInvoke (OpenProcessHandle).
Process[] processes = Process.GetProcessesByName("explorer");
This is a bit hacky. WMI can also be used for this.
It might be a good idea to set winmgmt as a dependency for your service if you decided to go with solution that uses WMI.

How can I get tokenGroups from active directory on Windows Server 2003?

I'm trying to load tokenGroups from Active Directory but it isn't working once deployed to a Windows Server (2003). I cannot figure out why, since it works fine locally...
Here is my error:
There is no such object on the server.
And here is my code (the sid variable is the current users SecurityIdentifier pulled from HttpContext):
DirectoryEntry userDE = new DirectoryEntry(string.Format("LDAP://<SID={0}>", sid.Value))
userDE.RefreshCache(new[] { "tokenGroups" });
var tokenGroups = userDE.Properties["tokenGroups"] as CollectionBase;
groups = tokenGroups.Cast<byte[]>()
.Select(sid => new SecurityIdentifier(sid, 0)).ToArray();
Any ideas why I would get that error?
UPDATE: The error actually happens on the RefreshCache line
Do you have a valid value for userDE after the constructor call?? Does that user really exist? Or do you need to provide e.g. a server to use in your LDAP path??
The error message No such object on server seems to indicate the user just plain doesn't exist.... (or cannot be found, due to e.g. permissions)
Try this - not sure if that's the problem, but it's worth a try - it should work:
DirectoryEntry userDE = new DirectoryEntry(string.Format("LDAP://<SID={0}>", sid.Value))
userDE.RefreshCache(new string[] { "tokenGroups" });
Try using new string[] instead of just new[].

What is a good unique PC identifier?

I've been looking at the code in this tutorial, and I found that it uses My.Computer.Name to save settings that shouldn't roam between computers. It's entirely possible, however, for a user to have two identically named PCs. If they wanted to have the same username on each PC, for example, they may very well end up with two PCs named Username-PC.
What are some good methods of identifying different PCs? Do PCs have GUIDs associated with them, or should I look into pulling the serial number off of some hardware? I don't care if the identification persists through reinstallation of Windows.
(The tutorial I linked is in VB.Net, but I'm implementing it in C#)
Some good identifiers:
MAC Address: It's fairly easy to get at, and it's usually unique. However, it can be spoofed/changed rather easily, so it depends on how unique it needs to be.
CPU Serial Number: It's not available on lots of older systems, but it's there. Check out this MSDN page. It won't change, but it's bound to a computer.
HDD Serial Number: It's likely to not change, but can be a nuisance if the HD fails. Check out this MSDN page.
If you are on windows HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\ CurrentVersion\ProductId is unique per machine/per windows install. where as in some of the other answers like the MAC address, Proc SN, and HD SN will stay the same between windows reinstalls/dual boot situations.
The real answer to that question: There is no such thing.
There are several "close enough" solutions, but each one of those has it's own limitation.
All the hardware IDs - Hardware changes. And, in many cases you can change those identifiers (For example, MAC spoofing).
The SID, as I've already commented, Is not that good as well, because the SID won't change if the computer was installed from an image. The SID is generated by windows installation, if windows wasn't installed, but copied from an image, the SID won't change (although it is common to regenerate it because of a myth about "security risk" - you can't count on that).
Computer name - Well, as mentioned, They suppose to be unique, but it's not enforced in any way.
Another solution you can implement is to generate you own unique identifier and store it locally (assuming you can do such thing). Again, this solution won't work if your computer was imaged with your application.
The best solution for you really depends on what you are trying to accomplish.
I had the same problem with a quite large network, and the best solution in my case was the computer's name.
If you are absolutely sure that your process won't be imaged, I would generate a unique identifier using Guid because it will probably be the safest.
Here is a way to uniquely identify a computer.
Using System.Management to get Win32_BIOS, you can get unique values from your machine's BIOS.
See: Win32_BIOS class, http://msdn.microsoft.com/en-us/library/aa394077.aspx
using System.Management;
string UniqueMachineId()
{
StringBuilder builder = new StringBuilder();
String query = "SELECT * FROM Win32_BIOS";
ManagementObjectSearcher searcher = new ManagementObjectSearcher(query);
// This should only find one
foreach (ManagementObject item in searcher.Get())
{
Object obj = item["Manufacturer"];
builder.Append(Convert.ToString(obj));
builder.Append(':');
obj = item["SerialNumber"];
builder.Append(Convert.ToString(obj));
}
return builder.ToString();
}
With similar logic, you can also step through "Win32_DiskDrive";
http://msdn.microsoft.com/en-us/library/aa394132.aspx;
and get "SerialNumber" for each physical drive. In this case, the
foreach (ManagementObject item in searcher.Get())
should find multiple items
Take three identifiers that are semi-unique and semi-constant. Use the rule that 2 out of 3 is sufficient for a positive identification. Update the registered data for the 1 out of 3 that is occasionally wrong.
Use the network card's MAC address. It's supposed to be unique. It can be changed, though. It depends on how malicious you expect your users to be and how critical your application is.
Some sample code to do it:
public string GetMACAddress() {
ManagementClass mc = new ManagementClass("Win32_NetworkAdapterConfiguration");
ManagementObjectCollection moc = mc.GetInstances();
string MACAddress = String.Empty;
foreach (ManagementObject mo in moc) {
if (MACAddress == String.Empty) { // only return MAC Address from first card
if ((bool)mo["IPEnabled"] == true) MACAddress = mo["MacAddress"].ToString();
}
mo.Dispose();
}
return MACAddress;
}
One thing you can use is the MAC of any Network interface. You can also combine several sources of information. Like HDD Serial number, mac, processor type to calculate a hash from it.
I don't think it's possible to have two PC's with the same name on the same domain. Have you tried capturing the domain name?
Take a look here: Getting Service Tag from Dell Machine using .net?
You could snatch some unique data from the registry.
Each computer has a SID that's unique under normal circumstances.
In a managed network environment, the best, most reliable identifier might be the one you create, but there are some downsides.
Some (many?) manufacturers provide a utility that allows you to set an asset tag that is stored in the firmware. This might be a bootable utility, or it might run within Windows, or it might even be built into the firmware setup. This "tag" is an arbitrary text string that you can set to whatever you want, and then read it back using WMI and the Win32_SystemEnclosure class...
string[] selectedProperties = new string[] { "SMBIOSAssetTag" };
ObjectQuery enclosureQuery = new SelectQuery("Win32_SystemEnclosure", null, selectedProperties);
using (ManagementObjectSearcher enclosureSearcher = new ManagementObjectSearcher(enclosureQuery))
using (ManagementObjectCollection enclosureCollection = enclosureSearcher.Get())
{
foreach (ManagementObject enclosure in enclosureCollection)
{
string assetTag = (string) enclosure.GetPropertyValue("SMBIOSAssetTag");
}
}
Pros:
You can use whatever scheme you want (e.g. incorporating date, department, incrementing integers, GUIDs, etc.).
You can use one scheme for all machines regardless of their manufacturer, instead of having to handle manufacturer-specific schemes.
By allocating and tracking the identifiers yourself, you can guarantee that they are unique. Not relying on an identifier set by the manufacturer means there is no risk of duplicates within a manufacturer or between manufacturers.
The identifier is stored in the firmware — not on the hard drive — so it will survive reformatting, upgrades, etc. but also not be duplicated by backups/imaging/cloning.
Cons:
You need to actually set the asset tag; they'll all be blank until you do so.
Setting a machine's asset tag may require physical access and a reboot.
Asset tags are not write-once and could, therefore, be changed or erased.
Password-protected firmware should require that password before changing the tag, but that's not guaranteed.
By allocating and tracking the identifiers yourself, there's not only the overhead of...allocating and tracking the identifiers, but also the possibility that you'll introduce duplicates if you're not careful.
Using asset tags for this purpose requires that all machines support setting an asset tag and properly report it to WMI.
We use a combination of the ProcessorID from Win32_processor and the UUID from Win32_ComputerSystemProduct:
ManagementObjectCollection mbsList = null;
ManagementObjectSearcher mos = new ManagementObjectSearcher("Select ProcessorID From Win32_processor");
mbsList = mos.Get();
string processorId = string.Empty;
foreach (ManagementBaseObject mo in mbsList)
{
processorId = mo["ProcessorID"] as string;
}
mos = new ManagementObjectSearcher("SELECT UUID FROM Win32_ComputerSystemProduct");
mbsList = mos.Get();
string systemId = string.Empty;
foreach (ManagementBaseObject mo in mbsList)
{
systemId = mo["UUID"] as string;
}
var compIdStr = $"{processorId}{systemId}";
Previously, we used a combination: processor ID ("Select ProcessorID From Win32_processor") and the motherboard serial number ("SELECT SerialNumber FROM Win32_BaseBoard"), but then we found out that the serial number of the motherboard may not be filled in, or it may be filled in with uniform values:
To be filled by O.E.M.
None
Default string
Therefore, it is worth considering this situation.
Also keep in mind that the ProcessorID number may be the same on different computers.
There is a sample code with complete notes in this link for getting CPU and HD Drive ID: http://www.vcskicks.com/hardware_id.php
add this dll to refrences
System.Management.dll
for CPU ID:
string cpuInfo = string.Empty;
ManagementClass mc = new ManagementClass("win32_processor");
ManagementObjectCollection moc = mc.GetInstances();
foreach (ManagementObject mo in moc)
{
if (cpuInfo == "")
{
//Get only the first CPU's ID
cpuInfo = mo.Properties["processorID"].Value.ToString();
break;
}
}
return cpuInfo;
and for Hard Drive ID (Volume Serial):
ManagementObject dsk = new ManagementObject(#"win32_logicaldisk.deviceid=""" + drive + #":""");
dsk.Get();
string volumeSerial = dsk["VolumeSerialNumber"].ToString();

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