I'm really struggling with saving data to my local network NAS (a Synology DS214 if that matters).
I need to store some files in my network folders after creating them in another part of my program, but I haven't been able to handle the authentication/permissions properly.
My code atm is this:
WrapperImpersonationContext WIContext =
new WrapperImpersonationContext("\\\\DiskStation", "admin", "admin");
try
{
WIContext.Enter();
// code to select the final path simplified.
string fileName = "file.txt";
string originalPath = Environment.GetFolderPath(
Environment.SpecialFolder.MyDocuments);
originalPath= Path.Combine(new string[] {originalPath, fileName});
string finalPath = "\\\\DiskStation\\Virtual\\DestFolder";
if (!Directory.Exists(finalPath))
{
// This goes well for whatever reason
Directory.CreateDirectory(finalPath);
}
finalPath = Path.Combine(new string[] {finalPath, fileName});
// This fails for wrong username/password
File.Move(originalPath, finalPath);
} catch (Exception ex)
{
// Exception showing simplified here
MessageBox.Show(ex.ToString());
throw;
} finally
{
WIContext.Leave();
}
The code used for the WrapperImpersonationContext I found here:
WindowsImpersonationContext made easy
As written in my code when I try to move the file I get an UnauthorizedAccessException: Access to the path is denied. I also tried to create a new file in the network folder with the same results.
While looking at the Michiel Vanotegem's code linked above, I discovered that I get an authentication error calling the LogonUser function (error code 1326 that gets me a Win32Exception (0x80004005): The user name or password is incorrect).
I tried to use the WNetUseConnection function looking at this and this pages but while I get no error from the function (after substituting it in the Michiel code), when I try to move the file I get the same UnauthorizedAccessException: Access to the path is denied.
I also tried to fiddle with the domain passed to the Impersonation Wrapper but I couldn't seem to make it work. I feel like I'm missing something... Can someone kindly point me to the right direction or help me with this issue?
Ty all who contributes in advance.
Edit 15/12/2017 11:52: I discovered that if I try to rerun the LogonUser function immediately after the first error I get a different exception (error 87 Win32Exception (0x80004005): The parameter is incorrect)
I followed on #LennartStoop suggestion, so I enclosed my code in a using block instead of a try finally using the code I borrowed from this answer:
using (NetworkConnection netConn =
new NetworkConnection("\\\\DiskStation", new NetworkCredential("admin", "admin")))
{
// My code here
}
Using this I've been able to establish a connection the network folder and perform all the IO operation I needed so ty very much for the tip Lennart :)
Related
I think this is a rather straightforward issue, but I don't have much information to go on. I have this code to try and read a DWG file into memory, so that I can read and manipulate the data. I am getting an error that the parameter "Value" cannot be null.
While that does let me know something is wrong, how do I proceed in figuring out what exactly this value is so that I can fix it?
string basePath = Path.Combine($"{Path.GetDirectoryName(System.Reflection.Assembly.GetEntryAssembly().Location)}", "temp");
string fileName = Path.Combine(basePath, "ATemplateV0.2.dwg");
if(File.Exists(fileName))
{
DwgReader dwgReader = new(fileName);
try
{
DxfModel dxfModel = dwgReader.Read();
}
catch (Exception e)
{
Console.WriteLine(e.Message);
}
}
WW CadLib needs a license to run, if you don't have one that may be causing the error.
The code example in the answer from #b166er is referring to an Open Source library called ACadSharp to read dwg/dxf files from one of my repositories.
Right now you can use a pre-release version of it in Nuget
You can pass a onNotification event into the DwgReader constructor that might give you more information. Examples here: https://github.com/DomCR/ACadSharp/blob/master/ACadSharp.Examples/Program.cs
I did find a few similar questions, but they weren't able to point me in the right direction... This may be something entirely stupid, but if anyone could tell me why I can't get a string populated I'd appreciate it. Here's my method that's failing:
private static string passwordTrace { get; set; }
// ... lots of other code
private static void RefreshPassword()
{
try
{
string filePath = "\\\\[server ip]\\share\\folder\\file.abcd";
string npDecrypted;
DateTime lastRefreshDate = Properties.Settings.Default.lastRefresh;
if (DateTime.Now >= lastRefreshDate.AddDays(30))
{
using (StreamReader sr = new StreamReader(filePath))
{
string npEncrypted = sr.ReadLine();
if (npEncrypted.Length != 24)
{
string fr = File.ReadAllText(filePath);
npEncrypted = fr.Substring(0, 24);
}
npDecrypted = Decryptor(npEncrypted);
passwordTrace = npDecrypted; // added for debugging only! remove when done.
secureString npSecure = new SecureString();
foreach (char c in npDecrypted)
{
npSecure.AppendChar(c)
}
Properties.Settings.Default.adminpw = npSecure;
Properties.Settings.Default.Save();
}
}
}
catch (FileNotFoundException fnfe)
{
// code for handling this type of exception
}
catch (NullReferenceException nre)
{
// code for handling this type of exception
}
catch (Exception e)
{
// code to catch ANY other type of exception
}
}
Now, there are no errors or warnings when the VS debugger compiles everything, and it works correctly when debugging. But, if I copy the compiled exe (from C:\project\bin\Debug directory) and run it the issue arises.
The point that says passwordTrace = ... is called at another point by a message box. This works correctly when running via debugger and there aren't any exceptions thrown anywhere (I do have try/catches all over the place), but for whatever reason the PasswordTrace and the Properties.Settings.Default.adminpw don't seem to be holding their value throughout the applications execution.
Also, the file that is being read is an encrypted text file which will always have only 1 line of characters and that line is always 24 characters long. An example would be:
09sdjf09ausd08uf9!%38==
As a final statement, I also copied the app.exe.config and app.pdb to the server directory where I copied the compiled .exe file to see if that had anything to do with it and it didn't fix anything. I also tried running the .exe directly from the Debug directory (the same file that I'm copying elsewhere) and it works correctly. As soon as I move it off of the Local Disk it doesn't work.
So, my suspicions are that it has something to do with the environments working directory, or something to do with how the app is executing. I read something somewhere that noted the default users is not set, but I think that was specifically regarding ASP.NET. If that was the case and the user double-clicking on the .exe didn't have a proper network authentication then what would I do? And if it has something to do with the working directory, how can I circumvent this?
I'm gonna keep fiddling and if I figure it out I'll update this, but I'm so lost at the moment! lol! And for the last time - everything it/was working correctly until copying it to the server location.
Thanks in advance! :)
I try to copy the EventLog "Application" to another folder on my PC but always get the error that
"....Could not find a part of the path
'C:\Windows\System32\winevt\Logs\Application.evtx..."
I use the code:
public void collectEventLogsFromSystem(string RequestedlogName,string newFolderPath)
{
string combinedLogToFind = "HKEY_LOCAL_MACHINE\\SYSTEM\\CurrentControlSet\\Services\\Eventlog\\" + RequestedlogName;
string LogEventsPath = (string)Registry.GetValue(combinedLogToFind, "File", null);
if (LogEventsPath != null)
{
System.IO.File.Copy(LogEventsPath, newFolderPath +"\\"+ RequestedlogName, true);
}
}//collectEventLogsFromSystem method
Even if i use explicit folder path it won't work:
System.IO.File.Copy(#"C:\Windows\System32\winevt\Logs\Application.evtx", "c:\\ttt\\Application.evtx", true);
any idea?
I found this answer on StackOverflow which will probably solve your problem. I have a 64 bit machine which exhibited the same behavior. This post by John Rasch solved the issue and explains why it failed.
If you are trying to get the log file while the program is running, the way above will not work. This post Export Event Log (.evtx) without "run as administrator" will allow you to backup the event log, even if you are currently using the event log in your application.
I have to save images to a folder located in "c:\inetpub\wwwroot\" and named as "UploadedImages". Here is my code:
public string SaveImage(string base64,int compno)
{
string res = "";
try
{
using (MemoryStream ms = new MemoryStream(Convert.FromBase64String(base64)))
{
using (Bitmap bm2 = new Bitmap(ms))
{
bm2.Save(Server.MapPath("~/UploadedImages/ID"+compno+".jpg"));
}
}
res = "done";
}
catch (Exception ex) {
res = ex.ToString();
}
return res;
}
but it throws "A generic error occured in GDI+ at System.Drawing.Image.Save" exception. What am I doing wrong? This code works fine when saving image locally as
bm2.Save("D:Embasy\UploadedImages\ID"+compno+".jpg"));
What changes do I need to make to save images in localhost directory?
Your not going to believe this -- the site running v1.1 had a virtual directory set-up which was mapped to the directory in which the image was saved to -- things worked fine.
The v2.0 site also had the same virtual directory name, but the physical path was different -- I changed the path to point to the same directory as the v1.0 site and now the code works.
So in short -- you were right about the "path must exist".
Classes within the System.Drawing namespace are not supported for use within a Windows or ASP.NET service. Attempting to use these classes from within one of these application types may produce unexpected problems, such as diminished service performance and run-time exceptions. For a supported alternative, see Windows Imaging Components.
and kindly refer this link
http://msdn.microsoft.com/en-us/library/xs6ftd89.aspx
When you are using Server.Mappath
bm2.Save(Server.MapPath("~/UploadedImages/ID"+compno+".jpg"));
"~(tield)" : is point to project/application root folder c:\inetpub\wwwroot\yourproject
then find remaining your path /UploadedImages and then create ID1.jpg.
But your imagefolder "UploadImages" is exist in d: not in c:\inetpub\wwwroot\yourproject
if you want to exist your image folder in D: then you should to create
virtual directory and then you need to apply path as relevant
My problem actually was that every time i published website, I replaced the "UploadedImages" folder too and thus permissions were changed. So, i didnt replaced the folder again after changing its permissions and creating "everyone" group and giving full rights to it. Now code is working perfectly :)
In my C# .NET 2.0 application I'm accessing network paths, and I'd like to be able to tell the difference between paths that don't exist, and paths which do exist but for which I don't have access rights. I tried doing the following:
try
{
string[] contents = Directory.GetFileSystemEntries( path );
}
catch( Exception e )
{
if( e is DirectoryNotFoundException )
MessageBox.Show( "Path not found" );
else
MessageBox.Show( "Access denied" );
}
This works fine for local paths, but for network paths, the exception is always System.IO.IOException, regardless of the reason for the error. The exception Message field shows a different message depending on whether the path exists or not, so clearly the information is available at some point, but I can't get to it. Is there a way to differentiate between "path not found" and "access denied" for network paths?
Edit: So, in case anyone else wants the quick solution to this, as suggested by henrik, and incorporating peSHIr's advice, here is what you can do:
try
{
// Issue this call just to find out whether the path exists
// We don't care about the result
string[] contents = Directory.GetFileSystemEntries( path );
// If we get this far then the path exists.
}
catch( IOException e )
{
uint error = (uint)Marshal.GetHRForException( e );
if( error == (uint)0x80070041 ) // ERROR_NETWORK_ACCESS_DENIED
{
// The poor deluded user doesn't have access rights
this.SuperProprietaryTechniqueForGettingAccessRights();
}
else
{
// Hah! The idiot user specified a path that doesn't exist!
// Chastise them severely, like all good GUI should.
MessageBox.Show( "NO! BAD USER!" );
}
}
catch
{
// Swallow all other types of exception - we only made the call
// to find out whether the path exists.
}
First, I would not catch (Exception), but do something like this:
try {
string[] contents = Directory.GetFileSystemEntries(path);
}
catch(DirectoryNotFoundException)
{
MessageBox.Show("Path not found");
}
catch(IOException)
{
MessageBox.Show("Could not access path");
}
But the real question is: why would you actually need to know the difference, if all you do is show a message box to the user with a generic error message?
Also, unfortunately, the path may exist and you don't have access, and the result is that the path appears non-existent to your account. Many companies modify the special privs on a folder to remove "intermediary" folders from visibility, but they are still present.
For example, consider the path \srv\test1\test2\test3\
If you modify the advanced security for the folder named "test2" above, you can prevent users from navigating into it. Attempts to open the folder will result in a not found exception, and viewing the parent folder "test1" will not show the folder as present. However, if you provide the full path above and have sufficient privileges on the folder named "test3" then the folder will open.
Just something to consider, for all intents and purposes the folder doesn't exist for the user, however, if you offer the ability for a user to specify a full path then you should keep the above in mind (e.g. allow users to reach paths by full name, because it's possible they lack privs to view/list/read/see an intermediary, and the error returned doesn't indicate that it's a security restriction, so preventing access to the full path because of an intermediary appeared non-existent coudl be considered bugged app logic.)
Hope that helps.
You can call Marshal.GetHRForException to get more detailed information as in:
if (Marshal.GetHRForException(e) == unchecked((int)0x800704cf)) // ERROR_NETWORK_UNREACHABLE
See WinError.h for error codes.