Accessing a Shared File (UNC) From a Remote, Non-Trusted Domain With Credentials

Question

We\'ve run into an interesting situation that needs solving, and my searches have turned up nill. I therefore appeal to the SO community for help.

The issue is this:

Answer 1

Here a minimal POC class w/ all the cruft removed

using System;
using System.ComponentModel;
using System.Runtime.InteropServices;

public class UncShareWithCredentials : IDisposable
{
    private string _uncShare;

    public UncShareWithCredentials(string uncShare, string userName, string password)
    {
        var nr = new Native.NETRESOURCE
        {
            dwType = Native.RESOURCETYPE_DISK,
            lpRemoteName = uncShare
        };

        int result = Native.WNetUseConnection(IntPtr.Zero, nr, password, userName, 0, null, null, null);
        if (result != Native.NO_ERROR)
        {
            throw new Win32Exception(result);
        }
        _uncShare = uncShare;
    }

    public void Dispose()
    {
        if (!string.IsNullOrEmpty(_uncShare))
        {
            Native.WNetCancelConnection2(_uncShare, Native.CONNECT_UPDATE_PROFILE, false);
            _uncShare = null;
        }
    }

    private class Native
    {
        public const int RESOURCETYPE_DISK = 0x00000001;
        public const int CONNECT_UPDATE_PROFILE = 0x00000001;
        public const int NO_ERROR = 0;

        [DllImport("mpr.dll")]
        public static extern int WNetUseConnection(IntPtr hwndOwner, NETRESOURCE lpNetResource, string lpPassword, string lpUserID,
            int dwFlags, string lpAccessName, string lpBufferSize, string lpResult);

        [DllImport("mpr.dll")]
        public static extern int WNetCancelConnection2(string lpName, int dwFlags, bool fForce);

        [StructLayout(LayoutKind.Sequential)]
        public class NETRESOURCE
        {
            public int dwScope;
            public int dwType;
            public int dwDisplayType;
            public int dwUsage;
            public string lpLocalName;
            public string lpRemoteName;
            public string lpComment;
            public string lpProvider;
        }
    }
}

You can directly use \\server\share\folder w/ WNetUseConnection, no need to strip it to \\server part only beforehand.