DataProtector DataProtector DataProtector DataProtector Class

Definice

Poskytuje základní třídu pro ochrany dat pomocí.Provides the base class for data protectors.

public ref class DataProtector abstract
public abstract class DataProtector
type DataProtector = class
Public MustInherit Class DataProtector
Dědičnost
DataProtectorDataProtectorDataProtectorDataProtector
Odvozené

Příklady

Následující příklad ukazuje, jak vytvořit datové ochranu, která používá třídu ochranu s možností pro další entropie.The following example demonstrates how to create a data protector that uses a protection class with an option for extra entropy. Ve výchozím nastavení DataProtector třídy odvozeno hash účel vlastnosti, které mají data, která mají být šifrována.By default, the DataProtector class prepends the hash of the purpose properties to the data to be encrypted. Můžete vypnout, které tuto funkci a použít hodnotu hash účel jako další entropie při volání metody ochrana dat s možností další entropie.You can turn that functionality off and use the hashed purpose as extra entropy when calling a data protector with an extra entropy option.

using System;
using System.Security.Permissions;

namespace System.Security.Cryptography
{
    public sealed class MyDataProtector : DataProtector
    {
        public DataProtectionScope Scope { get; set; }
        // This implementation gets the HashedPurpose from the base class and passes it as OptionalEntropy to ProtectedData.
        // The default for DataProtector is to prepend the hash to the plain text, but because we are using the hash 
        // as OptionalEntropy there is no need to prepend it.
        protected override bool PrependHashedPurposeToPlaintext
        {
            get
            {
                return false;
            }
        }
        // To allow a service to hand out instances of a DataProtector we demand unrestricted DataProtectionPermission 
        // in the constructor, but Assert the permission when ProviderProtect is called.  This is similar to FileStream
        // where access is checked at time of creation, not time of use.
        [SecuritySafeCritical]
        [DataProtectionPermission(SecurityAction.Assert, ProtectData = true)]
        protected override byte[] ProviderProtect(byte[] userData)
        {
            // Delegate to ProtectedData
            return ProtectedData.Protect(userData, GetHashedPurpose(), Scope);
        }
        // To allow a service to hand out instances of a DataProtector we demand unrestricted DataProtectionPermission 
        // in the constructor, but Assert the permission when ProviderUnProtect is called.  This is similar to FileStream
        // where access is checked at time of creation, not time of use.
        [SecuritySafeCritical]
        [DataProtectionPermission(SecurityAction.Assert, UnprotectData = true)]
        protected override byte[] ProviderUnprotect(byte[] encryptedData)
        {
            // Delegate to ProtectedData
            return ProtectedData.Unprotect(encryptedData, GetHashedPurpose(), Scope);
        }
        public override bool IsReprotectRequired(byte[] encryptedData)
        {
            // For now, this cannot be determined, so always return true;
            return true;
        }
        // Public constructor
        // The Demand for DataProtectionPermission is in the constructor because we Assert this permission 
        // in the ProviderProtect/ProviderUnprotect methods. 
        [DataProtectionPermission(SecurityAction.Demand, Unrestricted = true)]
        [SecuritySafeCritical]
        public MyDataProtector(string appName, string primaryPurpose, params string[] specificPurpose)
            : base(appName, primaryPurpose, specificPurpose)
        {
        }
    }
}
Imports System
Imports System.Security
Imports System.Security.Cryptography
Imports System.Security.Permissions



Public NotInheritable Class MyDataProtector
    Inherits DataProtector

    Public Property Scope() As DataProtectionScope
        Get
            Return Scope
        End Get
        Set(value As DataProtectionScope)
        End Set
    End Property ' This implementation gets the HashedPurpose from the base class and passes it as OptionalEntropy to ProtectedData.
    ' The default for DataProtector is to prepend the hash to the plain text, but because we are using the hash 
    ' as OptionalEntropy there is no need to prepend it.

    Protected Overrides ReadOnly Property PrependHashedPurposeToPlaintext() As Boolean
        Get
            Return False
        End Get
    End Property

    ' To allow a service to hand out instances of a DataProtector we demand unrestricted DataProtectionPermission 
    ' in the constructor, but Assert the permission when ProviderProtect is called.  This is similar to FileStream
    ' where access is checked at time of creation, not time of use.
    <SecuritySafeCritical(), DataProtectionPermission(SecurityAction.Assert, ProtectData:=True)> _
    Protected Overrides Function ProviderProtect(ByVal userData() As Byte) As Byte()
        ' Delegate to ProtectedData
        Return ProtectedData.Protect(userData, GetHashedPurpose(), Scope)

    End Function 'ProviderProtect

    ' To allow a service to hand out instances of a DataProtector we demand unrestricted DataProtectionPermission 
    ' in the constructor, but Assert the permission when ProviderUnProtect is called.  This is similar to FileStream
    ' where access is checked at time of creation, not time of use.
    <SecuritySafeCritical(), DataProtectionPermission(SecurityAction.Assert, UnprotectData:=True)> _
    Protected Overrides Function ProviderUnprotect(ByVal encryptedData() As Byte) As Byte()
        ' Delegate to ProtectedData
        Return ProtectedData.Unprotect(encryptedData, GetHashedPurpose(), Scope)

    End Function 'ProviderUnprotect

    Public Overrides Function IsReprotectRequired(ByVal encryptedData() As Byte) As Boolean
        ' For now, this cannot be determined, so always return true;
        Return True

    End Function 'IsReprotectRequired

    ' Public constructor
    ' The Demand for DataProtectionPermission is in the constructor because we Assert this permission 
    ' in the ProviderProtect/ProviderUnprotect methods. 
    <DataProtectionPermission(SecurityAction.Demand, Unrestricted:=True), SecuritySafeCritical()> _
    Public Sub New(ByVal appName As String, ByVal primaryPurpose As String, ParamArray specificPurpose() As String)
        MyBase.New(appName, primaryPurpose, specificPurpose)

    End Sub 'New
End Class 'MyDataProtector

Následující příklad ukazuje jednoduchý datový ochranného zařízení, která používá PrependHashedPurposeToPlaintext funkce DataProtector třídy.The following example demonstrates a simple data protector that uses the PrependHashedPurposeToPlaintext functionality of the DataProtector class.

using System;
using System.Security.Permissions;

namespace System.Security.Cryptography
{
    public sealed class MemoryProtector : DataProtector
    {
        public MemoryProtectionScope Scope { get; set; }
        protected override bool PrependHashedPurposeToPlaintext 
        {
            get
            {
                // Signal the DataProtector to prepend the hash of the purpose to the data.
                return true;
            }
        }
        // To allow a service to hand out instances of a DataProtector we demand unrestricted DataProtectionPermission 
        // in the constructor, but Assert the permission when ProviderProtect is called.  This is similar to FileStream
        // where access is checked at time of creation, not time of use.
        [SecuritySafeCritical]
        [DataProtectionPermission(SecurityAction.Assert, ProtectData = true)]
        protected override byte[] ProviderProtect(byte[] userData)
        {
            
            // Delegate to ProtectedData
            ProtectedMemory.Protect(userData, Scope);
            return userData;
        }
        // To allow a service to hand out instances of a DataProtector we demand unrestricted DataProtectionPermission 
        // in the constructor, but Assert the permission when ProviderUnprotect is called..  This is similar to FileStream
        // where access is checked at time of creation, not time of use.
        [SecuritySafeCritical]
        [DataProtectionPermission(SecurityAction.Assert, UnprotectData = true)]
        protected override byte[] ProviderUnprotect(byte[] encryptedData)
        {

            ProtectedMemory.Unprotect(encryptedData,Scope);           
                return encryptedData;
        }

        public override bool IsReprotectRequired(byte[] encryptedData)
        {
            // For now, this cannot be determined so always return true.
            return true;
        }
        // Public constructor
        // The Demand for DataProtectionPermission is in the constructor because we Assert this permission 
        // in the ProviderProtect/ProviderUnprotect methods. 
        [DataProtectionPermission(SecurityAction.Demand, Unrestricted = true)]
        [SecuritySafeCritical]
        public MemoryProtector(string appName, string primaryPurpose, params string[] specificPurpose)
            : base(appName, primaryPurpose, specificPurpose)
        {
        }
    }
}
Imports System
Imports System.Security
Imports System.Security.Permissions
Imports System.Security.Cryptography



Public NotInheritable Class MemoryProtector
    Inherits DataProtector

    Public Property Scope() As MemoryProtectionScope
        Get
            Return Scope
        End Get
        Set(value As MemoryProtectionScope)
        End Set
    End Property

    Protected Overrides ReadOnly Property PrependHashedPurposeToPlaintext() As Boolean
        Get
            ' Signal the DataProtector to prepend the hash of the purpose to the data.
            Return True
        End Get
    End Property

    ' To allow a service to hand out instances of a DataProtector we demand unrestricted DataProtectionPermission 
    ' in the constructor, but Assert the permission when ProviderProtect is called.  This is similar to FileStream
    ' where access is checked at time of creation, not time of use.
    <SecuritySafeCritical(), DataProtectionPermission(SecurityAction.Assert, ProtectData:=True)> _
    Protected Overrides Function ProviderProtect(ByVal userData() As Byte) As Byte()

        ' Delegate to ProtectedData
        ProtectedMemory.Protect(userData, Scope)
        Return userData

    End Function 'ProviderProtect

    ' To allow a service to hand out instances of a DataProtector we demand unrestricted DataProtectionPermission 
    ' in the constructor, but Assert the permission when ProviderUnprotect is called..  This is similar to FileStream
    ' where access is checked at time of creation, not time of use.
    <SecuritySafeCritical(), DataProtectionPermission(SecurityAction.Assert, UnprotectData:=True)> _
    Protected Overrides Function ProviderUnprotect(ByVal encryptedData() As Byte) As Byte()

        ProtectedMemory.Unprotect(encryptedData, Scope)
        Return encryptedData

    End Function 'ProviderUnprotect

    Public Overrides Function IsReprotectRequired(ByVal encryptedData() As Byte) As Boolean
        ' For now, this cannot be determined so always return true.
        Return True

    End Function 'IsReprotectRequired

    ' Public constructor
    ' The Demand for DataProtectionPermission is in the constructor because we Assert this permission 
    ' in the ProviderProtect/ProviderUnprotect methods. 
    <DataProtectionPermission(SecurityAction.Demand, Unrestricted:=True), SecuritySafeCritical()> _
    Public Sub New(ByVal appName As String, ByVal primaryPurpose As String, ParamArray specificPurpose() As String)
        MyBase.New(appName, primaryPurpose, specificPurpose)

    End Sub 'New
End Class 'MemoryProtector

Poznámky

Tato třída chrání uložených dat zobrazení a manipulaci.This class protects stored data from viewing and tampering. Vytvoření instance této třídy a použitím přesné účelové řetězce, které se používaly pro ochranu dat je získat přístup k chráněným datům.The access to the protected data is obtained by creating an instance of this class and using the exact purpose strings that were used to protect the data. Klíč k ochraně nebo zrušení ochrany dat není potřeba volající.The caller does not need a key to either protect or unprotect the data. Poskytuje klíč šifrovacího algoritmu.The key is provided by the encryption algorithm.

Odvozené třídy musí přepsat ProviderProtect a Unprotect metody, které DataProtector základní třídy zavolá zpět.Derived classes must override the ProviderProtect and Unprotect methods, which the DataProtector base class calls back into. Musí také přepsat IsReprotectRequired metodu, která se kdykoli vrátit true s možnou ztrátou malé účinnosti při aktualizaci aplikace jejich databáze uložené šifrovaného textu.They must also override the IsReprotectRequired method, which can always return true with a potential small loss of efficiency when applications refresh their database of stored cipher text. Odvozené třídy musí poskytovat konstruktor, který volá konstruktor základní třídy, která nastavuje hodnoty ApplicationName, SpecificPurposes, a PrimaryPurpose vlastnosti.Derived classes should provide a constructor that calls the base class constructor, which sets the ApplicationName, SpecificPurposes, and PrimaryPurpose properties.

Konstruktory

DataProtector(String, String, String[]) DataProtector(String, String, String[]) DataProtector(String, String, String[]) DataProtector(String, String, String[])

Vytvoří novou instanci třídy DataProtector pomocí zadaný název aplikace, primárním účelem a konkrétní účely.Creates a new instance of the DataProtector class by using the provided application name, primary purpose, and specific purposes.

Vlastnosti

ApplicationName ApplicationName ApplicationName ApplicationName

Získá název aplikace.Gets the name of the application.

PrependHashedPurposeToPlaintext PrependHashedPurposeToPlaintext PrependHashedPurposeToPlaintext PrependHashedPurposeToPlaintext

Určuje, zda-the-hash je přidáno jako předpona pole text před šifrování.Specifies whether the hash is prepended to the text array before encryption.

PrimaryPurpose PrimaryPurpose PrimaryPurpose PrimaryPurpose

Získá primárním účelem pro chráněná data.Gets the primary purpose for the protected data.

SpecificPurposes SpecificPurposes SpecificPurposes SpecificPurposes

Získá konkrétní účely pro chráněná data.Gets the specific purposes for the protected data.

Metody

Create(String, String, String, String[]) Create(String, String, String, String[]) Create(String, String, String, String[]) Create(String, String, String, String[])

Vytvoří instanci implementace ochrana dat s použitím názvu zadanou třídu ochrana dat, název aplikace, primárním účelem a konkrétní účely.Creates an instance of a data protector implementation by using the specified class name of the data protector, the application name, the primary purpose, and the specific purposes.

Equals(Object) Equals(Object) Equals(Object) Equals(Object)

Určuje, zda se zadaný objekt rovná aktuálnímu objektu.Determines whether the specified object is equal to the current object.

(Inherited from Object)
GetHashCode() GetHashCode() GetHashCode() GetHashCode()

Slouží jako výchozí funkce hash.Serves as the default hash function.

(Inherited from Object)
GetHashedPurpose() GetHashedPurpose() GetHashedPurpose() GetHashedPurpose()

Vytvoří hodnotu hash hodnoty vlastností, které jsou určené konstruktorem.Creates a hash of the property values specified by the constructor.

GetType() GetType() GetType() GetType()

Získá Type aktuální instance.Gets the Type of the current instance.

(Inherited from Object)
IsReprotectRequired(Byte[]) IsReprotectRequired(Byte[]) IsReprotectRequired(Byte[]) IsReprotectRequired(Byte[])

Určuje, zda je vyžadováno pro zadaný šifrovaná data znova šifrovat.Determines if re-encryption is required for the specified encrypted data.

MemberwiseClone() MemberwiseClone() MemberwiseClone() MemberwiseClone()

Vytvoří Mělkou kopii aktuální Object.Creates a shallow copy of the current Object.

(Inherited from Object)
Protect(Byte[]) Protect(Byte[]) Protect(Byte[]) Protect(Byte[])

Chrání zadaná uživatelská data.Protects the specified user data.

ProviderProtect(Byte[]) ProviderProtect(Byte[]) ProviderProtect(Byte[]) ProviderProtect(Byte[])

Určuje delegát metody v odvozené třídě, která Protect(Byte[]) metodu v základní třídě volá zpět do.Specifies the delegate method in the derived class that the Protect(Byte[]) method in the base class calls back into.

ProviderUnprotect(Byte[]) ProviderUnprotect(Byte[]) ProviderUnprotect(Byte[]) ProviderUnprotect(Byte[])

Určuje delegát metody v odvozené třídě, která Unprotect(Byte[]) metodu v základní třídě volá zpět do.Specifies the delegate method in the derived class that the Unprotect(Byte[]) method in the base class calls back into.

ToString() ToString() ToString() ToString()

Vrací řetězec, který představuje aktuální objekt.Returns a string that represents the current object.

(Inherited from Object)
Unprotect(Byte[]) Unprotect(Byte[]) Unprotect(Byte[]) Unprotect(Byte[])

Odemkne zadaná chráněná data.Unprotects the specified protected data.

Platí pro