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How to manage folders permissions on Mac OS with ACL in .NET Core 3.1.0

I have the following code in C#:
if (!Directory.Exists(inputFolder))
{
return true;
}
else
{
var me = new DirectoryInfo(inputFolder);
AuthorizationRuleCollection rules = null;
WindowsIdentity identity = null;
try
{
rules = me.GetAccessControl().GetAccessRules(true, true, typeof(SecurityIdentifier));
identity = WindowsIdentity.GetCurrent();
}
catch (UnauthorizedAccessException uae)
{
return false;
}
string userSID = identity.User.Value;
foreach (FileSystemAccessRule rule in rules)
{
if ((rule.FileSystemRights.HasFlag(FileSystemRights.Read) ||
rule.FileSystemRights.HasFlag(FileSystemRights.ReadAttributes) ||
rule.FileSystemRights.HasFlag(FileSystemRights.ReadData) ||
rule.FileSystemRights.HasFlag(FileSystemRights.ReadAndExecute)) && rule.AccessControlType == AccessControlType.Deny)
{
return false;
}
}
return true;
}
And it works correctly in Windows, however, when I try to run this on mac OS X (Visual Studio for Mac) it throws an exception when trying to get the information from the method "GetAccessRules" or even the "GetAccessControl" saying:
"Access Control List (ACL) APIs are part of resource management on Windows and are not supported on this platform."
So here is my question:
Is there an alternative to do this in .net core? Or how should i manage these kind of permissions in .net core but in mac OS X?

I am assuming you are using System.IO.FileSystem.AccessControl to make GetAccessControl() work on .NET Core? Unfortunately these APIs are closely tied to Windows low level APIs and won't work on Unix/Linux systems.
However, there is an alternative. You could give Mono.Posix.NETStandard a try. Here is the Nuget link.
You can call UnixDirectoryInfo() and get or set FileAccessPermissions that way.

Updated
I found the solution and it was the same provided by Ruv in the answer above.
So, installing the Nuget Package Mono.Posix.NETStandard works. Just get the information of the directory/file:
var unixDirInfo = new Mono.Unix.UnixDirectoryInfo('path');
Then you can check the permissions like this:
unixDirInfo.canAccess(AccessModes.F_OK) // is a file or directory
unixDirInfo.canAccess(AccessModes.R_OK) // accessible for reading
unixDirInfo.canAccess(AccessModes.W_OK) // accessible for writing
unixDirInfo.canAccess(AccessModes.X_OK) // accessible for executing
or from the FileAccessPermissions:
FileAccessPermissions permissions = unixDirInfo.FileAccessPermissions;
permissions.HasFlag(FileAccessPermissions.UserRead);
permissions.HasFlag(FileAccessPermissions.UserWrite);
permissions.HasFlag(FileAccessPermissions.UserExecute);
permissions.HasFlag(FileAccessPermissions.UserExecute .UserReadWriteExecute);
You can check the FileAccessPermission enum for more information.

SharpShell server .dll NOT signed

I need to develop a Shell Context Menu extension that references some other custom assemblies... I don't want to assign a Strong Name Key to those custom assemblies!
The guide I followed to do this uses the SharpShell project and illustrates how to sign (but does not expalins why) the assembly... and this is my problem: if I sign my final .dll then I have many errors during my project's building phase, because some assemblies my project references are not strongly named ("Referenced assembly does not have a strong name").
In general, googling about the C# Shell Extension implementation, all best tutorials I found sign the final assembly... is it mandatory?
Without signing the assembly ServerManager.exe returns this error: "The file 'XYZ.dll' is not a SharpShell Server".

Finally I've solved my troubles... the SharpShell.dll file obtained through NuGet was a different version of the ServerManager.exe ones.
Uninstalling the SharpShell NuGet package and directly referencing the SharpShell.dll you find inside the ServerManager folder was my solution!
Moreover, I was looking between the article comments... please read this question.

You don't need to use old DLL.
Please use this code directly, without using ServerManager.exe.
private static ServerEntry serverEntry = null;
public static ServerEntry SelectedServerEntry
{
get
{
if (serverEntry == null)
serverEntry = ServerManagerApi.LoadServer("xxx.dll");
return serverEntry;
}
}
public static ServerEntry LoadServer(string path)
{
try
{
// Create a server entry for the server.
var serverEntry = new ServerEntry();
// Set the data.
serverEntry.ServerName = Path.GetFileNameWithoutExtension(path);
serverEntry.ServerPath = path;
// Create an assembly catalog for the assembly and a container from it.
var catalog = new AssemblyCatalog(Path.GetFullPath(path));
var container = new CompositionContainer(catalog);
// Get the exported server.
var server = container.GetExport<ISharpShellServer>().Value;
serverEntry.ServerType = server.ServerType;
serverEntry.ClassId = server.GetType().GUID;
serverEntry.Server = server;
return serverEntry;
}
catch (Exception)
{
// It's almost certainly not a COM server.
MessageBox.Show("The file '" + Path.GetFileName(path) + "' is not a SharpShell Server.", "Warning");
return null;
}
}
Install code:
ServerRegistrationManager.InstallServer(SelectedServerEntry.Server, RegistrationType.OS64Bit, true);
Register code:
ServerRegistrationManager.RegisterServer(SelectedServerEntry.Server, RegistrationType.OS64Bit);

How to uninstall application programmatically

I tried this,this to uninstall the application programmatically. I am not getting any error or exception but the application is not uninstalled from my machine. Please see tried code also
public static string GetUninstallCommandFor(string productDisplayName)
{
RegistryKey localMachine = Registry.LocalMachine;
string productsRoot = #"SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UserData\S-1-5-18\Products";
RegistryKey products = localMachine.OpenSubKey(productsRoot);
string[] productFolders = products.GetSubKeyNames();
foreach (string p in productFolders)
{
RegistryKey installProperties = products.OpenSubKey(p + #"\InstallProperties");
if (installProperties != null)
{
string displayName = (string)installProperties.GetValue("DisplayName");
if ((displayName != null) && (displayName.Contains(productDisplayName)))
{
string uninstallCommand =(string)installProperties.GetValue("UninstallString");
return uninstallCommand;
}
}
}
return "";
}
Please help me to uninstall the application programmatically using C#.

The above routine will return a string, assuming it found a match that may look like:
MsiExec.exe /X{02DA0248-DB55-44A7-8DC6-DBA573AEEA94}
You need to take that and run it as a process:
System.Diagnostics.Process.Start(uninstallString);
Note that it may not be always msiexec, it can be anything that the program chooses to specify. In case of msiexec, you can append /q parameter to your uninstallString to make it uninstall silently (and it won't show those Repair/Remove dialogs).
Update: If you're using Windows installer 3.0 or above, you can also use /quiet for silent install/uninstall. It's basically same as /qn (if you're on older versions). Source. Thanks #JRO for bringing it up!

What's wrong with Registry.GetValue?

I trying to get a registry value:
var value = Registry.GetValue(#"HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Cryptography", "MachineGuid", 0);
In Windows XP all ok, but in Windows 7 returns 0. In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Cryptography using regedit I see MachineGuid, but if I run
var keys = Registry.LocalMachine.OpenSubKey("SOFTWARE").OpenSubKey("Microsoft").OpenSubKey("Cryptography", RegistryKeyPermissionCheck.ReadSubTree).GetValueNames();
keys.Length is 0.
What do I do wrong? With other values all ok in both of OS.

The problem is that you probably are compiling the solution as x86, if you compile as x64 you can read the values.
Try the following code compiling as x86 and x64:
class Program
{
static void Main(string[] args)
{
Console.WriteLine("MachineGUID:" + MachineGUID);
Console.ReadKey();
}
public static string MachineGUID
{
get
{
Guid guidMachineGUID;
if (Microsoft.Win32.Registry.LocalMachine.OpenSubKey("SOFTWARE\\Microsoft\\Cryptography") != null)
{
if (Microsoft.Win32.Registry.LocalMachine.OpenSubKey("SOFTWARE\\Microsoft\\Cryptography").GetValue("MachineGuid") != null)
{
guidMachineGUID = new Guid(Microsoft.Win32.Registry.LocalMachine.OpenSubKey("SOFTWARE\\Microsoft\\Cryptography").GetValue("MachineGuid").ToString());
return guidMachineGUID.ToString();
}
}
return null;
}
}
}
You can read more about Accessing an Alternate Registry View.
You can found in here a way of reading values in x86 and x64.

It probably has to do with UAC (User Account Control). The extra layer of protection for Windows Vista and Windows 7.
You'll need to request permissions to the registry.
EDIT:
Your code right now:
var keys = Registry.LocalMachine.OpenSubKey("SOFTWARE")
.OpenSubKey("Microsoft")
.OpenSubKey("Cryptography", RegistryKeyPermissionCheck.ReadSubTree)
.GetValueNames();
Only requests the permissions on the Cryptography subkey, maybe that causes the problem (at least I had that once), so the new code would then be:
var keys = Registry.LocalMachine.OpenSubKey("SOFTWARE", RegistryKeyPermissionCheck.ReadSubTree)
.OpenSubKey("Microsoft", RegistryKeyPermissionCheck.ReadSubTree)
.OpenSubKey("Cryptography", RegistryKeyPermissionCheck.ReadSubTree)
.GetValueNames();
EDIT2:
I attached the debugger to it, on this code:
var key1 = Registry.LocalMachine.OpenSubKey("SOFTWARE", RegistryKeyPermissionCheck.ReadSubTree);
var key2 = key1.OpenSubKey("Microsoft", RegistryKeyPermissionCheck.ReadSubTree);
var key3 = key2.OpenSubKey("Cryptography", RegistryKeyPermissionCheck.ReadSubTree);
var key4 = key3.GetValueNames();
It turns out, you can read that specific value, at least that's my guess, because all data is correct, until I open key3, there the ValueCount is zero, instead of the expected 1.
I think it's a special value that's protected.

You say you're on 64-bit Windows: is your app 32-bit? If so it's probably being affected by registry redirection and is looking at HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Cryptography. You may have to P/Invoke to work around it: http://msdn.microsoft.com/en-us/library/aa384129.aspx.

If you're not an administrator, you only have read permission on HKLM. You need to open the key read-only instead. Not sure how to do that with .NET's Registry class; with the API directly, you use RegOpenKeyEx() with the KEY_READ flag.
EDIT: After checking MSDN, I see that OpenSubKey() does open read only, and returns the contents if it succeeds and nothing if it fails. Since you're chaining multiple OpenSubKey calls, it's most likely one of them that's failing that causes the others to fail. Try breaking them out into separate calls, and checking the intermediate values returned.

Maybe a little late to the party, but, none of the solutions worked for me.
This is how I've solved this issue:
public static Guid GetMachineGuid
{
get
{
var machineGuid = Guid.Empty;
var localMachineX64View = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine, RegistryView.Registry64);
var cryptographySubKey = localMachineX64View.OpenSubKey(#"SOFTWARE\Microsoft\Cryptography");
if (cryptographySubKey == null) return machineGuid;
var machineGuidValue = (string)cryptographySubKey.GetValue("MachineGuid");
Guid.TryParse(machineGuidValue, out machineGuid);
return machineGuid;
}
}

I solved the problem when i imported Microsoft.Win32 and changed the application-settings to x64 like pedrocgsousa mentioned.

How to search for specific value in Registry keys

How can I search for specific value in the registry keys?
For example I want to search for XXX in
HKEY_CLASSES_ROOT\Installer\Products
any code sample in C# will be appreciated,
thanks

In case you don't want to take a dependency on LogParser (as powerful as it is): I would take a look at the Microsoft.Win32.RegistryKey class (MSDN). Use OpenSubKey to open up HKEY_CLASSES_ROOT\Installer\Products, and then call GetSubKeyNames to, well, get the names of the subkeys.
Open up each of those in turn, call GetValue for the value you're interested in (ProductName, I guess) and compare the result to what you're looking for.

Help here...
Microsoft has a great (but not well known) tool for this - called LogParser
It uses a SQL engine to query all kind of text based data like the Registry,
the Filesystem, the eventlog, AD etc...
To be usable from C#, you need to build an Interop Assembly from the
Logparser.dll COM server using following (adjust LogParser.dll path)
command.
tlbimp "C:\Program Files\Log Parser 2.2\LogParser.dll"
/out:Interop.MSUtil.dll
Following is a small sample, that illustrates how to query for the Value
'VisualStudio' in the \HKLM\SOFTWARE\Microsoft tree.
using System;
using System.Runtime.InteropServices;
using LogQuery = Interop.MSUtil.LogQueryClass;
using RegistryInputFormat = Interop.MSUtil.COMRegistryInputContextClass;
using RegRecordSet = Interop.MSUtil.ILogRecordset;
class Program
{
public static void Main()
{
RegRecordSet rs = null;
try
{
LogQuery qry = new LogQuery();
RegistryInputFormat registryFormat = new RegistryInputFormat();
string query = #"SELECT Path from \HKLM\SOFTWARE\Microsoft where
Value='VisualStudio'";
rs = qry.Execute(query, registryFormat);
for(; !rs.atEnd(); rs.moveNext())
Console.WriteLine(rs.getRecord().toNativeString(","));
}
finally
{
rs.close();
}
}
}

This method will search a specified registry key for the first subkey that contains a specified value. If the key is found then the specified value is returned. Searchign is only one level deep. If you require deeper searching then I suggest modifying this code to make use of recursion. Searching is case-sensitive but again you can modify that if required.
private string SearchKey(string keyname, string data, string valueToFind, string returnValue)
{
RegistryKey uninstallKey = Registry.LocalMachine.OpenSubKey(keyname);
var programs = uninstallKey.GetSubKeyNames();
foreach (var program in programs)
{
RegistryKey subkey = uninstallKey.OpenSubKey(program);
if (string.Equals(valueToFind, subkey.GetValue(data, string.Empty).ToString(), StringComparison.CurrentCulture))
{
return subkey.GetValue(returnValue).ToString();
}
}
return string.Empty;
}
Example usage
// This code will find the version of Chrome (32 bit) installed
string version = this.SearchKey("SOFTWARE\\WOW6432Node\\Microsoft\\Windows\\CurrentVersion\\Uninstall", "DisplayName", "Google Chrome", "DisplayVersion");

#Caltor your solution gave me the answer I was looking for. I welcome improvements or a completely different solution that does not involve the registry. I am working with enterprise applications on Windows 10 with devices joined to Azure AD. I want/need to use Windows Hello for devices and for HoloLens 2 in a UWP app. My problem has been getting the AAD userPrincipal name from Windows 10. After a couple days searching and trying lots of code I searched the Windows Registry for my AAD account in the Current User key and found it. With some research it appears that this information is in a specific key. Because you can be joined to multiple directories there may be more than one entry. I was not trying to solve that issue, that is done with the AAD tenant Id. I just needed the AAD userPrincipal name.
My solution de-dups the return list so that I have a list of unique userPrincipal names. App users may have to select an account, this is tolerable for even HoloLens.
using Microsoft.Win32;
using System.Collections.Generic;
using System.Linq;
namespace WinReg
{
public class WinRegistryUserFind
{
// Windows 10 apparently places Office/Azure AAD in the registry at this location
// each login gets a unique key in the registry that ends with the aadrm.com and the values
// are held in a key named Identities and the value we want is the Email data item.
const string regKeyPath = "SOFTWARE\\Classes\\Local Settings\\Software\\Microsoft\\MSIPC";
const string matchOnEnd = "aadrm.com";
const string matchKey = "Identities";
const string matchData = "Email";
public static List<string> GetAADuserFromRegistry()
{
var usersFound = new List<string>();
RegistryKey regKey = Registry.CurrentUser.OpenSubKey(regKeyPath);
var programs = regKey.GetSubKeyNames();
foreach (var program in programs)
{
RegistryKey subkey = regKey.OpenSubKey(program);
if(subkey.Name.EndsWith(matchOnEnd))
{
var value = (subkey.OpenSubKey(matchKey) != null)? (string)subkey.OpenSubKey(matchKey).GetValue(matchData): string.Empty;
if (string.IsNullOrEmpty(value)) continue;
if((from user in usersFound where user == value select user).FirstOrDefault() == null)
usersFound.Add(value) ;
}
}
return usersFound;
}
}
}