MaskGenerationMethod Class
Important
Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.
Represents the abstract class from which all mask generator algorithms must derive.
public ref class MaskGenerationMethod abstract
[System.Runtime.Versioning.UnsupportedOSPlatform("browser")]
public abstract class MaskGenerationMethod
public abstract class MaskGenerationMethod
[System.Runtime.InteropServices.ComVisible(true)]
public abstract class MaskGenerationMethod
[<System.Runtime.Versioning.UnsupportedOSPlatform("browser")>]
type MaskGenerationMethod = class
type MaskGenerationMethod = class
[<System.Runtime.InteropServices.ComVisible(true)>]
type MaskGenerationMethod = class
Public MustInherit Class MaskGenerationMethod
- Inheritance
-
MaskGenerationMethod
- Derived
- Attributes
The following code example demonstrates how to derive from the MaskGenerationMethod class.
#using <System.dll>
using namespace System;
using namespace System::Security::Cryptography;
namespace Contoso
{
ref class MaskGenerator: MaskGenerationMethod
{
private:
String^ hashNameValue;
public:
// Initialize a mask to encrypt using the SHA256 algorithm.
MaskGenerator()
{
hashNameValue = "SHA256";
}
// Create a mask with the specified seed.
virtual array<Byte>^ GenerateMask(array<Byte>^ seed, int maskLength) override
{
HashAlgorithm^ hash;
array<Byte>^ rgbCounter = gcnew array<Byte>(4);
array<Byte>^ targetRgb = gcnew array<Byte>(maskLength);
UInt32 counter = 0;
for (int inc = 0; inc < targetRgb->Length; )
{
ConvertIntToByteArray(counter++, rgbCounter);
hash = (HashAlgorithm^)CryptoConfig::CreateFromName(
hashNameValue);
array<Byte>^ temp = gcnew array<Byte>(
4 + seed->Length);
Buffer::BlockCopy(rgbCounter, 0, temp, 0, 4);
Buffer::BlockCopy(seed, 0, temp, 4, seed->Length);
hash->ComputeHash(temp);
if (targetRgb->Length - inc > hash->HashSize / 8)
{
Buffer::BlockCopy(hash->Hash, 0, targetRgb, inc,
hash->Hash->Length);
}
else
{
Buffer::BlockCopy(hash->Hash, 0, targetRgb, inc,
targetRgb->Length - inc);
}
inc += hash->Hash->Length;
}
return targetRgb;
}
private:
// Convert the specified integer to the byte array.
void ConvertIntToByteArray(UInt32 source,
array<Byte>^ targetBytes)
{
UInt32 remainder;
int inc = 0;
// Clear the array prior to filling it.
Array::Clear(targetBytes, 0, targetBytes->Length);
while (source > 0)
{
remainder = source % 256;
targetBytes[ 3 - inc ] = (Byte)remainder;
source = (source - remainder) / 256;
inc++;
}
}
};
// This class demonstrates how to create the MaskGenerator class
// and call its GenerateMask member.
ref class MaskGeneratorImpl
{
public:
void static Work()
{
array<Byte>^ seed = gcnew array<Byte>(4){
0x01,0x02,0x03,0x04};
int length = 16;
MaskGenerator^ maskGenerator = gcnew MaskGenerator;
array<Byte>^ mask = maskGenerator->GenerateMask(seed,
length);
Console::WriteLine("Generated the following mask:");
Console::WriteLine(System::Text::Encoding::
ASCII::get()->GetString(mask));
Console::WriteLine("This sample completed successfully;"
" press Enter to exit.");
Console::ReadLine();
}
};
}
void main()
{
Contoso::MaskGeneratorImpl::Work();
}
//
// This sample produces the following output:
//
// Generated the following mask:
// ?"TFd(?~OtO?
// This sample completed successfully; press Enter to exit.
using System;
using System.Security.Cryptography;
namespace Contoso
{
class MaskGenerator : System.Security.Cryptography.MaskGenerationMethod
{
private String HashNameValue;
// Initialize a mask to encrypt using the SHA256 algorithm.
public MaskGenerator()
{
HashNameValue = "SHA256";
}
// Create a mask with the specified seed.
override public byte[] GenerateMask(byte[] seed, int maskLength)
{
HashAlgorithm hash;
byte[] rgbCounter = new byte[4];
byte[] targetRgb = new byte[maskLength];
uint counter = 0;
for (int inc = 0; inc < targetRgb.Length; )
{
ConvertIntToByteArray(counter++, ref rgbCounter);
hash = (HashAlgorithm)
CryptoConfig.CreateFromName(HashNameValue);
byte[] temp = new byte[4 + seed.Length];
Buffer.BlockCopy(rgbCounter, 0, temp, 0, 4);
Buffer.BlockCopy(seed, 0, temp, 4, seed.Length);
hash.ComputeHash(temp);
if (targetRgb.Length - inc > hash.HashSize/8)
{
Buffer.BlockCopy(
hash.Hash,
0,
targetRgb,
inc,
hash.Hash.Length);
}
else
{
Buffer.BlockCopy(
hash.Hash,
0,
targetRgb,
inc,
targetRgb.Length - inc);
}
inc += hash.Hash.Length;
}
return targetRgb;
}
// Convert the specified integer to the byte array.
private void ConvertIntToByteArray(
uint sourceInt,
ref byte[] targetBytes)
{
uint remainder;
int inc = 0;
// Clear the array prior to filling it.
Array.Clear(targetBytes, 0, targetBytes.Length);
while (sourceInt > 0)
{
remainder = sourceInt % 256;
targetBytes[3 - inc] = (byte) remainder;
sourceInt = (sourceInt - remainder)/256;
inc++;
}
}
}
// This class demonstrates how to create the MaskGenerator class
// and call its GenerateMask member.
class MaskGeneratorImpl
{
public static void Main(string[] args)
{
byte[] seed = new byte[] {0x01, 0x02, 0x03, 0x04};
int length = 16;
MaskGenerator maskGenerator = new MaskGenerator();
byte[] mask = maskGenerator.GenerateMask(seed, length);
Console.WriteLine("Generated the following mask:");
Console.WriteLine(System.Text.Encoding.ASCII.GetString(mask));
Console.WriteLine("This sample completed successfully; " +
"press Enter to exit.");
Console.ReadLine();
}
}
}
//
// This sample produces the following output:
//
// Generated the following mask:
// ?"TFd(?~OtO?
// This sample completed successfully; press Enter to exit.
Imports System.Security.Cryptography
Public Class MaskGenerator
Inherits System.Security.Cryptography.MaskGenerationMethod
Private HashNameValue As String
' Initialize a mask to encrypt using the SHA256 algorithm.
Public Sub New()
HashNameValue = "SHA256"
End Sub
' Create a mask with the specified seed.
Public Overrides Function GenerateMask( _
ByVal seed() As Byte, _
ByVal maskLength As Integer) As Byte()
Dim hash As HashAlgorithm
Dim rgbCounter(4) As Byte
Dim targetRgb(maskLength) As Byte
Dim counter As Integer
For inc As Int16 = 0 To targetRgb.Length
ConvertIntToByteArray(counter + 1, rgbCounter)
hash = CType( _
CryptoConfig.CreateFromName(HashNameValue), _
HashAlgorithm)
Dim temp(4 + seed.Length) As Byte
Buffer.BlockCopy(rgbCounter, 0, temp, 0, 4)
Buffer.BlockCopy(seed, 0, temp, 4, seed.Length)
hash.ComputeHash(temp)
If (targetRgb.Length - inc > hash.HashSize / 8) Then
Buffer.BlockCopy( _
hash.Hash, 0, targetRgb, inc, hash.Hash.Length)
Else
Buffer.BlockCopy( _
hash.Hash, 0, targetRgb, inc, targetRgb.Length - inc)
End If
inc += hash.Hash.Length
Next
Return targetRgb
End Function
' Convert the specified integer to the byte array.
Private Sub ConvertIntToByteArray( _
ByVal sourceInt As Integer, _
ByRef targetBytes() As Byte)
Dim remainder As Integer
Dim inc As Int16 = 0
' Clear the array prior to filling it.
Array.Clear(targetBytes, 0, targetBytes.Length)
While (sourceInt > 0)
remainder = sourceInt Mod 256
targetBytes(3 - inc) = CType(remainder, Byte)
sourceInt = (sourceInt - remainder) / 256
inc = inc + 1
End While
End Sub
End Class
Public Class Form1
Inherits System.Windows.Forms.Form
' Event handler for Run button.
Private Sub Button1_Click( _
ByVal sender As System.Object, _
ByVal e As System.EventArgs) Handles Button1.Click
tbxOutput.Cursor = Cursors.WaitCursor
tbxOutput.Text = ""
Dim seed() As Byte = {&H1, &H2, &H3, &H4}
Dim length As Int16 = 16
Dim maskGenerator As New MaskGenerator
Dim mask() As Byte = maskGenerator.GenerateMask(seed, length)
tbxOutput.AppendText("Generated the following mask:")
tbxOutput.AppendText(System.Text.Encoding.ASCII.GetString(mask))
' Align interface and conclude application.
tbxOutput.AppendText(vbCrLf + "This sample completed" + _
"successfully; press Exit to continue.")
tbxOutput.Cursor = Cursors.Default
End Sub
' Event handler for Exit button.
Private Sub Button2_Click( _
ByVal sender As System.Object, _
ByVal e As System.EventArgs) Handles Button2.Click
Application.Exit()
End Sub
#Region " Windows Form Designer generated code "
Public Sub New()
MyBase.New()
'This call is required by the Windows Form Designer.
InitializeComponent()
'Add any initialization after the InitializeComponent() call
End Sub
'Form overrides dispose to clean up the component list.
Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
If disposing Then
If Not (components Is Nothing) Then
components.Dispose()
End If
End If
MyBase.Dispose(disposing)
End Sub
'Required by the Windows Form Designer
Private components As System.ComponentModel.IContainer
'NOTE: The following procedure is required by the Windows Form Designer
'It can be modified using the Windows Form Designer.
'Do not modify it using the code editor.
Friend WithEvents Panel2 As System.Windows.Forms.Panel
Friend WithEvents Panel1 As System.Windows.Forms.Panel
Friend WithEvents Button1 As System.Windows.Forms.Button
Friend WithEvents Button2 As System.Windows.Forms.Button
Friend WithEvents tbxOutput As System.Windows.Forms.RichTextBox
<System.Diagnostics.DebuggerStepThrough()> _
Private Sub InitializeComponent()
Me.Panel2 = New System.Windows.Forms.Panel
Me.Button1 = New System.Windows.Forms.Button
Me.Button2 = New System.Windows.Forms.Button
Me.Panel1 = New System.Windows.Forms.Panel
Me.tbxOutput = New System.Windows.Forms.RichTextBox
Me.Panel2.SuspendLayout()
Me.Panel1.SuspendLayout()
Me.SuspendLayout()
'
'Panel2
'
Me.Panel2.Controls.Add(Me.Button1)
Me.Panel2.Controls.Add(Me.Button2)
Me.Panel2.Dock = System.Windows.Forms.DockStyle.Bottom
Me.Panel2.DockPadding.All = 20
Me.Panel2.Location = New System.Drawing.Point(0, 320)
Me.Panel2.Name = "Panel2"
Me.Panel2.Size = New System.Drawing.Size(616, 64)
Me.Panel2.TabIndex = 1
'
'Button1
'
Me.Button1.Dock = System.Windows.Forms.DockStyle.Right
Me.Button1.Font = New System.Drawing.Font( _
"Microsoft Sans Serif", _
9.0!, _
System.Drawing.FontStyle.Regular, _
System.Drawing.GraphicsUnit.Point, _
CType(0, Byte))
Me.Button1.Location = New System.Drawing.Point(446, 20)
Me.Button1.Name = "Button1"
Me.Button1.Size = New System.Drawing.Size(75, 24)
Me.Button1.TabIndex = 2
Me.Button1.Text = "&Run"
'
'Button2
'
Me.Button2.Dock = System.Windows.Forms.DockStyle.Right
Me.Button2.Font = New System.Drawing.Font( _
"Microsoft Sans Serif", _
9.0!, _
System.Drawing.FontStyle.Regular, _
System.Drawing.GraphicsUnit.Point, _
CType(0, Byte))
Me.Button2.Location = New System.Drawing.Point(521, 20)
Me.Button2.Name = "Button2"
Me.Button2.Size = New System.Drawing.Size(75, 24)
Me.Button2.TabIndex = 3
Me.Button2.Text = "E&xit"
'
'Panel1
'
Me.Panel1.Controls.Add(Me.tbxOutput)
Me.Panel1.Dock = System.Windows.Forms.DockStyle.Fill
Me.Panel1.DockPadding.All = 20
Me.Panel1.Location = New System.Drawing.Point(0, 0)
Me.Panel1.Name = "Panel1"
Me.Panel1.Size = New System.Drawing.Size(616, 320)
Me.Panel1.TabIndex = 2
'
'tbxOutput
'
Me.tbxOutput.AccessibleDescription = _
"Displays output from application."
Me.tbxOutput.AccessibleName = "Output textbox."
Me.tbxOutput.Dock = System.Windows.Forms.DockStyle.Fill
Me.tbxOutput.Location = New System.Drawing.Point(20, 20)
Me.tbxOutput.Name = "tbxOutput"
Me.tbxOutput.Size = New System.Drawing.Size(576, 280)
Me.tbxOutput.TabIndex = 1
Me.tbxOutput.Text = "Click the Run button to run the application."
'
'Form1
'
Me.AutoScaleBaseSize = New System.Drawing.Size(6, 15)
Me.ClientSize = New System.Drawing.Size(616, 384)
Me.Controls.Add(Me.Panel1)
Me.Controls.Add(Me.Panel2)
Me.Name = "Form1"
Me.Text = "MaskGenerationMethod"
Me.Panel2.ResumeLayout(False)
Me.Panel1.ResumeLayout(False)
Me.ResumeLayout(False)
End Sub
#End Region
End Class
'
' This sample produces the following output:
'
' Generated the following mask:~&*(uj98U(*UD989D
' This sample completedsuccessfully; press Exit to continue.
Derived classes of MaskGenerationMethod compute masks that are used in key exchange algorithms such as Optimal Asymmetric Encryption Padding (OAEP).
This class is used by implementations of key exchange algorithms only for mask generation. Application code does not use this class directly.
Mask |
Initializes a new instance of the MaskGenerationMethod class. |
Equals(Object) |
Determines whether the specified object is equal to the current object. (Inherited from Object) |
Generate |
When overridden in a derived class, generates a mask with the specified length using the specified random seed. |
Get |
Serves as the default hash function. (Inherited from Object) |
Get |
Gets the Type of the current instance. (Inherited from Object) |
Memberwise |
Creates a shallow copy of the current Object. (Inherited from Object) |
To |
Returns a string that represents the current object. (Inherited from Object) |
Produkt | Versjoner |
---|---|
.NET | Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9 |
.NET Framework | 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1 |
.NET Standard | 2.0, 2.1 |
.NET-tilbakemelding
.NET er et åpen kilde-prosjekt. Velg en kobling for å gi tilbakemelding: