Re: Effective Security Access Check [modified] - C# Discussion Boards

Kefaleas Stavros25-Dec-07 10:26

25-Dec-07 10:26

How can I alter this code

<br />
using System;<br />
<br />
public class Analysis<br />
{<br />
   public void ProcessExamResults()<br />
   {<br />
      // initializing variables in declarations<br />
      int passes = 0; // number of passes<br />
      int failures = 0; // number of failures<br />
      int studentCounter = 1; // student counter<br />
      int result; // one exam result from user<br />
<br />
      // process 10 students using counter-controlled repetition<br />
      while ( studentCounter <= 10 )<br />
      {<br />
         // prompt user for input and obtain value from user<br />
         Console.Write( "Enter result (1 = pass, 2 = fail): " );<br />
         result = Convert.ToInt32( Console.ReadLine() );<br />
<br />
         // if...else nested in while <br />
         if ( result == 1 ) // if result 1,<br />
            passes = passes + 1; // increment passes           <br />
         else // else result is not 1, so<br />
            failures = failures + 1; // increment failures<br />
<br />
         // increment studentCounter so loop eventually terminates<br />
         studentCounter = studentCounter + 1;<br />
      } // end while<br />
<br />
      // termination phase; prepare and display results<br />
      Console.WriteLine( "Passed: {0}\nFailed: {1}", passes, failures );<br />
<br />
      // determine whether more than 8 students passed<br />
      if ( passes > 8 )<br />
         Console.WriteLine( "Raise Tuition" );<br />
   } // end method ProcessExamResults<br />
} // end class Analysis<br />

so that it can validate its inputs.I want the app to keep looping until the user enters a correct value.
Thnx!

Re: How to validate the inputs

Ed.Poore25-Dec-07 14:48

Ed.Poore

25-Dec-07 14:48

Firstly, this looks surprisingly like a homework question.
Secondly, this is very simple.
Thirdly, it would help if you specified what valid inputs are (I know I could read them from the code but I'm lazy).

My Blog[^]

Re: How to validate the inputs

KaptinKrunch26-Dec-07 8:06

KaptinKrunch

26-Dec-07 8:06

Write a static function that checks for a valid input entry. Then for each entry, pass it through the function

Example function

public static bool IsValidEntry(int entry)
{
switch(entry)
{
case 1:
return false;
break;
case 2:
return true;
break;
default:
return false;
}
}

Effective Security Access Check

Jeffrey Walton25-Dec-07 7:42

Jeffrey Walton

25-Dec-07 7:42

Hi All,

I want to check in advance on Write permission to a Directory for a sanity check. It is similar to File.Exist() and Directory.Exist().

I haven't been able to get the keywords correct to find the function. So far, I seem to be hitting on CAS (a miserable embodiment for System Administrators).

Can anyone point me in the proper direction?

Jeff

Re: Effective Security Access Check

Jeffrey Walton25-Dec-07 8:05

Jeffrey Walton

25-Dec-07 8:05

Here's what I have hacked so far. There are two problems.

1) I can't seem to work with GetAccessRule()
2) I don't know how to make the compare, even though I believe I have all the players assembled.

Jeff

DirectoryInfo information = new DirectoryInfo(directory);
DirectorySecurity security = information.GetAccessControl();

WindowsIdentity user = WindowsIdentity.GetCurrent();
SecurityIdentifier sid = user.User;

// Passing sid below will not compile
AuthorizationRuleCollection rules =
security.GetAccessRules(false, true, /*???*/);

// How is the check performed?
if( HasWriteAccess( rules ) )

Re: Effective Security Access Check

martin_hughes26-Dec-07 2:11

martin_hughes

26-Dec-07 2:11

This guy seems to have done the same thing... http://www.eggheadcafe.com/software/aspnet/30271754/check-users-directory-per.aspx[^]

"On one of my cards it said I had to find temperatures lower than -8. The numbers I uncovered were -6 and -7 so I thought I had won, and so did the woman in the shop. But when she scanned the card the machine said I hadn't.

"I phoned Camelot and they fobbed me off with some story that -6 is higher - not lower - than -8 but I'm not having it."
-Tina Farrell, a 23 year old thicky from Levenshulme, Manchester.

Re: Effective Security Access Check

Jeffrey Walton28-Dec-07 8:08

Jeffrey Walton

28-Dec-07 8:08

Hi Martin,

martin_hughes wrote:
This guy seems to have done the same thing

I ran across that earlier. His implementation is flawed. He does not consider a User Account ACE versus a Group ACE.

This means if an object has a DACL with a User Allow _and_ a Group Deny, the code will incorrectly return the object is not accessible.

Jeff

Re: Effective Security Access Check [modified]

martin_hughes28-Dec-07 9:28

martin_hughes

28-Dec-07 9:28

Hi Jeff,

I've been fiddling a bit - I haven't come up with a total solution (I am a bit hung over), but hopefully it's enough to give you a head start on the syntax etc... On with the code!

static void UserRights()
{
    DirectorySecurity ds = Directory.GetAccessControl(@"C:\test");
    WindowsIdentity user = WindowsIdentity.GetCurrent();

    bool IsInGroupWithWriteAcces = false;
    //This one gets all the groups that a user is in
    IdentityReferenceCollection irc = user.Groups;

    //Loop through all the groups the user is in...
    for (int i = 0; i < irc.Count; i++)
    {

        //Loop through all the access rules in the DirectorySecurity
        foreach (AccessRule ar in ds.GetAccessRules(true, true,
            typeof(System.Security.Principal.SecurityIdentifier)))
        {
            //Cast the AccessRule into a FileSystemAccessRule to make use of it
            FileSystemAccessRule fs = (FileSystemAccessRule)ar;

            //Now test to see if the current group has AccesControlType.Allow
            //and if the FileSystemRights are FileSystemRights.Write
            //I do a logical AND here:
            //      (fs.FileSystemRights & FileSystemRights.Write) == FileSystemRights.Write)
            //because fs.FileSystemRights returns all the
            //FileSystemRights in one go and performing the AND let's us just get
            //the Write that we're interested in.
            if ((fs.AccessControlType == AccessControlType.Allow
                && (fs.FileSystemRights & FileSystemRights.Write) == FileSystemRights.Write) &&
                fs.IdentityReference == irc[i])
            {
                Console.WriteLine("Yay, we're in a group with Write Access!");
                //Since we're in a group with Write access here, we could return true...
                //IsInGroupWithWriteAcces = true;
                //return IsInGroupWithWriteAcces;
            }
            else
            {
                //this group didn't contain write access
                Console.WriteLine("Whoops!");
            }

        }
    }
    return IsInGroupWithWriteAcces;
}

And to check if a User Account has permissions, all you need do is remove the for loop and simply test against the user.User SID.

static void UserRights2()
  {
      DirectorySecurity ds = Directory.GetAccessControl(@"C:\test");
      WindowsIdentity user = WindowsIdentity.GetCurrent();

      bool IsInGroupWithWriteAcces = false;

          //Loop through all the access rules in the DirectorySecurity
          foreach (AccessRule ar in ds.GetAccessRules(true, true,
              typeof(System.Security.Principal.SecurityIdentifier)))
          {
              //Cast the AccessRule into a FileSystemAccessRule to make use of it
              FileSystemAccessRule fs = (FileSystemAccessRule)ar;

              //Now test to see if the current group has AccesControlType.Allow
              //and if the FileSystemRights are FileSystemRights.Write
              //I do a logical AND here:
              //      (fs.FileSystemRights &amp;amp; FileSystemRights.Write) == FileSystemRights.Write)
              //because fs.FileSystemRights returns all the
              //FileSystemRights in one go and performing the AND let's us just get
              //the Write that we're interested in.
              if ((fs.AccessControlType == AccessControlType.Allow
                  && (fs.FileSystemRights & FileSystemRights.Write) == FileSystemRights.Write) &&
                  fs.IdentityReference == user.User)
              {
                  Console.WriteLine("Yay, we're a User with Write Access!");
                  //Since we're in a group with Write access here, we could return true...
                  //IsInGroupWithWriteAcces = true;
                  //return IsInGroupWithWriteAcces;
              }
              else
              {
                  //Were not a User with write access.
                  Console.WriteLine("Whoops!");
              }

          }

      //return IsInGroupWithWriteAcces;
  }

The rest should be just a matter of working out in which order things are applied/take precedence.

Cheers,

Martin

modified on Friday, December 28, 2007 4:51:42 PM

I ate too much... and another nice C# 3.0 feature

martin_hughes25-Dec-07 6:17

martin_hughes

25-Dec-07 6:17

The turkey is sitting heavily below the Christmas Pud... but I really like 3.0's auto implementing properties Smile | :)

Re: I ate too much... and another nice C# 3.0 feature

Jeffrey Walton25-Dec-07 7:39

Jeffrey Walton

25-Dec-07 7:39

martin_hughes wrote:
but I really like 3.0's auto implementing properties

3.5 was released last week. But I'm further behind - I'm still using 2.0

Re: I ate too much... and another nice C# 3.0 feature

martin_hughes25-Dec-07 7:50

martin_hughes

25-Dec-07 7:50

.Net 3.5 did... but the language is C# 3.0! Yay for confusion!

Re: I ate too much... and another nice C# 3.0 feature

Waleed Eissa25-Dec-07 17:09

Waleed Eissa

25-Dec-07 17:09

Anything interesting other than LINQ?

Waleed Eissa
.NET Software Developer in Sydney

Re: I ate too much... and another nice C# 3.0 feature

martin_hughes26-Dec-07 2:28

martin_hughes

26-Dec-07 2:28

Semi-tied in to LINQ, but extension methods are pretty sweet too!

Exercise Solution

Kefaleas Stavros24-Dec-07 23:52

Kefaleas Stavros

24-Dec-07 23:52

I have met this exercise in a book I am reading :

Develop a C# application that will determine whether any of several department-store customers has exceeded the credit limit on a charge account. For each customer, the following facts are available:

account number

balance at the beginning of the month

total of all items charged by the customer this month

total of all credits applied to the customer's account this month

allowed credit limit.

The application should input all these facts as integers, calculate the new balance (= beginning balance + charges credits), display the new balance and determine whether the new balance exceeds the customer's credit limit. For those customers whose credit limit is exceeded, the application should display the message "Credit limit exceeded". Use sentinel-controlled repetition to obtain the data for each account.

I have tried to code this solution and I came to this source code :

CustomerTest.cs :

using System;<br />
<br />
public class CustomerTest<br />
{<br />
    public static void Main(string[] args)<br />
    {<br />
        //Declarations<br />
        int account_Number;<br />
        int initial_Balance;<br />
        int total_Month_Items;<br />
        int total_Month_Credits;<br />
        int credit_Limit;<br />
        <br />
        <br />
        //create customer object<br />
        Customer myCustomer = new Customer(0, 0, 0, 0, 0);<br />
<br />
<br />
        //take input from the user<br />
        Console.Write("Enter account number or -1 to quit : ");<br />
        account_Number = Convert.ToInt32(Console.ReadLine());<br />
<br />
        //loop until sentinel value read from user<br />
        while (account_Number != -1)<br />
        {<br />
            Console.Write("Enter balance at the beggining of the month : ");<br />
            initial_Balance = Convert.ToInt32(Console.ReadLine());<br />
<br />
            Console.Write("Enter total of all items charged by the customer this month : ");<br />
            total_Month_Items = Convert.ToInt32(Console.ReadLine());<br />
<br />
            Console.Write("Enter total of all credits applied to the customer's account this month : ");<br />
            total_Month_Credits = Convert.ToInt32(Console.ReadLine());<br />
<br />
            Console.Write("Enter customer's credit limit : ");<br />
            credit_Limit = Convert.ToInt32(Console.ReadLine());<br />
<br />
            myCustomer.AccountNumber = account_Number;<br />
            myCustomer.InitialBalance = initial_Balance;<br />
            myCustomer.TotalMonthItems = total_Month_Items;<br />
            myCustomer.TotalMonthCredit = total_Month_Credits;<br />
            myCustomer.CreditLimit = credit_Limit;<br />
<br />
            //call DetermineNewBalance methd<br />
            myCustomer.DetermineNewBalance();<br />
<br />
        }<br />
    }<br />
}

Customer.cs :

using System;<br />
<br />
public class CustomerTest<br />
{<br />
    public static void Main(string[] args)<br />
    {<br />
        //Declarations<br />
        int account_Number;<br />
        int initial_Balance;<br />
        int total_Month_Items;<br />
        int total_Month_Credits;<br />
        int credit_Limit;<br />
        <br />
        <br />
        //create customer object<br />
        Customer myCustomer = new Customer(0, 0, 0, 0, 0);<br />
<br />
<br />
        //take input from the user<br />
        Console.Write("Enter account number or -1 to quit : ");<br />
        account_Number = Convert.ToInt32(Console.ReadLine());<br />
<br />
        //loop until sentinel value read from user<br />
        while (account_Number != -1)<br />
        {<br />
            Console.Write("Enter balance at the beggining of the month : ");<br />
            initial_Balance = Convert.ToInt32(Console.ReadLine());<br />
<br />
            Console.Write("Enter total of all items charged by the customer this month : ");<br />
            total_Month_Items = Convert.ToInt32(Console.ReadLine());<br />
<br />
            Console.Write("Enter total of all credits applied to the customer's account this month : ");<br />
            total_Month_Credits = Convert.ToInt32(Console.ReadLine());<br />
<br />
            Console.Write("Enter customer's credit limit : ");<br />
            credit_Limit = Convert.ToInt32(Console.ReadLine());<br />
<br />
            myCustomer.AccountNumber = account_Number;<br />
            myCustomer.InitialBalance = initial_Balance;<br />
            myCustomer.TotalMonthItems = total_Month_Items;<br />
            myCustomer.TotalMonthCredit = total_Month_Credits;<br />
            myCustomer.CreditLimit = credit_Limit;<br />
<br />
            //call DetermineNewBalance methd<br />
            myCustomer.DetermineNewBalance();<br />
<br />
        }<br />
    }<br />
}

The problem is in the first file when I use the sentinel-controlled repetition because I get no account number question at the second loop.Any ideas how to fix this one?Thnx!

Re: Exercise Solution

Luc Pattyn25-Dec-07 0:58

Luc Pattyn

25-Dec-07 0:58

A loop (for, while, ...) repeats whatever is inside, not what is in front of it. Smile | :)

Luc Pattyn [Forum Guidelines] [My Articles]

Happy Holidays!

A simple paint program-C#

Ali Rahimei24-Dec-07 22:48

Ali Rahimei

24-Dec-07 22:48

Hello everybody
I ask everyone who can disign a simple paint software lookalike winXP
of course I need the source&code in C#
As soon as possible,Please
alirahimei@yahoo.com
Thank you

Re: A simple paint program-C#

Luc Pattyn25-Dec-07 1:00

Luc Pattyn

25-Dec-07 1:00

The CodeProject site holds articles about almost anything, and has search facilities.
You must use them ASAP. Now. Urgently.

Smile | :)

Luc Pattyn [Forum Guidelines] [My Articles]

Happy Holidays!

Re: A simple paint program-C#

Paul Conrad25-Dec-07 10:33

Paul Conrad

25-Dec-07 10:33

Luc Pattyn wrote:
Urgently.

Oh my, the u-word Roll eyes | :rolleyes:

"Real programmers just throw a bunch of 1s and 0s at the computer to see what sticks" - Pete O'Hanlon

A simple paint program-C#

Ali Rahimei24-Dec-07 22:46

Ali Rahimei

24-Dec-07 22:46

Hello everybody
I ask everyone who can disign a simple paint software lookalike winXP
of course I need the source&code in C#
As soon as possible,Please

Re: A simple paint program-C#

Giorgi Dalakishvili24-Dec-07 23:03

Giorgi Dalakishvili

24-Dec-07 23:03

Did you search google? There is an open source program much better then paint

#region signature
my articles
#endregion

How i can user User Control in my own Form

wasimsharp24-Dec-07 21:23

wasimsharp

24-Dec-07 21:23

hi freind i want to change the Border the color of the Text box . friend of mine give me advice to use User Controland change the back color of the user Control.
Now the question is how i can User control in myForm

wasim khan

Re: How i can user User Control in my own Form

Xmen Real 25-Dec-07 2:53

Xmen Real

25-Dec-07 2:53

Dear Wasim,
instead of making user control write this code in Paint Event of Form

foreach (Control acontrol in this.Controls)
           {
               if (acontrol is TextBox)
               {
                   Pen myPen = new Pen(Color.White, 4.0F);
                   e.Graphics.DrawRectangle(myPen, new Rectangle(acontrol.Bounds.X, acontrol.Bounds.Y, acontrol.Bounds.Width, acontrol.Bounds.Height));
                   e.Graphics.Dispose();
               }
           }

hope this will help

Becoming Programmer...

Re: How i can user User Control in my own Form

wasimsharp25-Dec-07 19:33

wasimsharp

25-Dec-07 19:33

HI xmen_xwk
there is a little bit problem that Text box controls are not found the loop execute each time but it
never move inside the body of the loop the Text Boxes are inside the Group

wasim khan

Re: How i can user User Control in my own Form

Xmen Real 26-Dec-07 0:40

Xmen Real

26-Dec-07 0:40

as far as i understood that you were saying that textboxes are in groupbox
if yes, then just change this.Controls in this line :

foreach (Control acontrol in this.Controls)

with GroupName

foreach (Control acontrol in <<write group name>>)

Becoming Programmer...

Print Screen

half-life24-Dec-07 20:19

half-life

24-Dec-07 20:19

Hi, i'd like to have a menuitem
that ptints the screen directly to printer,

any idea where do i start
i did not found any thing Simple here

anyone?

THANKS

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