Using SecureString

Question

Can this be simplified to a one liner? Feel free to completely rewrite it as long as secureString gets initialized properly.

SecureString secureString = new          


        

Answer 1

Slight improvement on Sascha's answer replacing the lambda with a method group

"fizzbuzz".ToCharArray().ToList().ForEach(ss.AppendChar);

Answer 2

Since SecureString utilizes the IDispose interface. You could actually do it like this.

SecureString secure = new SecureString();
foreach(var character in data.ToCharArray())
    secure.AppendChar(character);

Essentially the data would be a parameter.

If you utilize the using to help alleviate resources; you'll want to be careful about the scope. But this may be a beneficial alternative, depending on usage.

Update:

You could actually do a full method signature:

public static SecureString ConvertStringToSecureString(this string data)
{
     var secure = new SecureString()
     foreach(var character in data.ToCharArray())
         secure.AppendChar(character);

     secure.MakeReadOnly();
     return secure;

}

For the decryption you would want to do:

public static string ConvertSecureStringToString(this SecureString data)
{
     var pointer = IntPtr.Zero;
     try
     {
          pointer = Marshal.SecureStringToGlobalAllocUnicode(data);
          return Marshal.PtrToStringUni(pointer);
     }
     finally
     {
          Marshal.ZeroFreeGlobalAllocUnicode(pointer);
     }
}

The following article will give you some additional information as well.

Answer 3

Apart from using unsafe code and a char*, there isn't a (much) better way.

The point here is not to copy SecureString contents to/from normal strings. The constant "fizzbuzz" constant is the security leak here.

Answer 4

You could use Linq:

"fizzbuzz".ToCharArray().ToList().ForEach(p => secureString.AppendChar(p));

Answer 5

var s = "fizzbuzz".Aggregate(new SecureString(), (ss, c) => { ss.AppendChar(c); return ss; });

Answer 6

Here is a how NetworkCredential class from .NET doing it:

SecureString secureString;
fixed (char* chPtr = plainString)
  secureString = new SecureString(chPtr, plainString.Length);

Ugly but probably the most efficient.