How to Read Remote Registry Keys?

Question

I need to be able to read the values in a specific Registry Key from a list of Remote Computers. I can do this locally with the following code

   using Microsoft.Win32;

        RegistryKey rkey = Registry.LocalMachine;
        RegistryKey rkeySoftware=rkey.OpenSubKey("Software");
        RegistryKey rkeyVendor = rkeySoftware.OpenSubKey("VendorName");
        RegistryKey rkeyVersions = rkeyVendor.OpenSubKey("Versions");

        String[] ValueNames = rkeyVersions.GetValueNames();
        foreach (string name in ValueNames)
        {
          MessageBox.Show(name + ": " + rkeyVersions.GetValue(name).ToString());
        }

but I don't know how to get the same info for a Remote Computer. Am I even using the right approach or should I be looking at WMI or something else?

Answer 1

The win32 API allows you to specify a computer name through RegConnectRegistry. I'm not sure that the .NET wrappers exposes this. You can also use WMI as you mentioned.

Answer 2

Look up OpenRemoteBaseKey().

Answer 3

You can achieve this through WMI, although I think you can also achieve it via the same mechanism (i.e. Microsoft.Win32 namespace classes) that you're currently using.

You need to look into the:

OpenRemoteBaseKey Method

The link above gives examples. It's should be as simple as something like:

// Open HKEY_CURRENT_USER\Environment 
// on a remote computer.
environmentKey = RegistryKey.OpenRemoteBaseKey(
                   RegistryHive.CurrentUser, remoteName).OpenSubKey(
                   "Environment");

Note, though, that'll there will be security implications in opening remote registry keys, so you may need to ensure that you have the relevant security permissions to do this. For that, you'll want to look into the:

SecurityPermission

and

RegistryPermission

classes in the System.Security.Permissions namespace.

Answer 4

I found that I could as CraigTP showed use the OpenRemoteBaseKey() method however it required me to change the permissions in the registry on the dest computers.

Here is the code I wrote that worked once I changed the permissions.

   RegistryKey rkey = RegistryKey.OpenRemoteBaseKey(RegistryHive.LocalMachine, "RemoteComputer");
        RegistryKey rkeySoftware = rkey.OpenSubKey("Software");
        RegistryKey rkeyVendor = rkeySoftware.OpenSubKey("VendorName");
        RegistryKey rkeyVersions = rkeyVendor.OpenSubKey("Versions");

        String[] ValueNames = rkeyVersions.GetValueNames();
        foreach (string name in ValueNames)
        {
            MessageBox.Show(name + ": " + rkeyVersions.GetValue(name).ToString());
        }

I also found that I could get the same info using WMI without having to modify the permissions. Here is the code with WMI.

 ManagementScope ms = new ManagementScope();
        ms.Path.Server = "flebbe";
        ms.Path.NamespacePath = "root\\default";
        ms.Options.EnablePrivileges = true;
        ms.Connect();

        ManagementClass mc = new ManagementClass("stdRegProv");
        mc.Scope = ms;

        ManagementBaseObject mbo;
        mbo = mc.GetMethodParameters("EnumValues");

        mbo.SetPropertyValue("sSubKeyName", "SOFTWARE\\VendorName\\Versions");

        string[] subkeys = (string[])mc.InvokeMethod("EnumValues", mbo, null).Properties["sNames"].Value;

        ManagementBaseObject mboS;
        string keyValue;

        foreach (string strKey in subkeys)
        {
            mboS = mc.GetMethodParameters("GetStringValue");
            mboS.SetPropertyValue("sSubKeyName", "SOFTWARE\\VendorName\\Versions");
            mboS.SetPropertyValue("sValueName", strKey);

            keyValue = mc.InvokeMethod("GetStringValue", mboS, null).Properties["sValue"].Value.ToString();
            MessageBox.Show(strKey + " : " + keyValue);
        }

P.S. I am calling the GetStringValue() method in the loop as I know all the values are strings. If there are multiple data types you would need to read the datatype from the Types output parameter of the EnumValues method.