Rfc2898DeriveBytes Rfc2898DeriveBytes Rfc2898DeriveBytes Rfc2898DeriveBytes Class

Definice

Implementuje funkce odvození klíče založené na heslech, PBKDF2 pomocí pseudo-náhodných čísel generátorů založeného na HMACSHA1.Implements password-based key derivation functionality, PBKDF2, by using a pseudo-random number generator based on HMACSHA1.

public ref class Rfc2898DeriveBytes : System::Security::Cryptography::DeriveBytes
[System.Runtime.InteropServices.ComVisible(true)]
public class Rfc2898DeriveBytes : System.Security.Cryptography.DeriveBytes
type Rfc2898DeriveBytes = class
    inherit DeriveBytes
Public Class Rfc2898DeriveBytes
Inherits DeriveBytes
Dědičnost
Rfc2898DeriveBytesRfc2898DeriveBytesRfc2898DeriveBytesRfc2898DeriveBytes
Atributy

Příklady

Následující příklad kódu používá Rfc2898DeriveBytes třídu k vytvoření dvou shodných klíčů TripleDES pro třídu.The following code example uses the Rfc2898DeriveBytes class to create two identical keys for the TripleDES class. Pak šifruje a dešifruje data pomocí klíčů.It then encrypts and decrypts some data using the keys.

using namespace System;
using namespace System::IO;
using namespace System::Text;
using namespace System::Security::Cryptography;

// Generate a key k1 with password pwd1 and salt salt1.
// Generate a key k2 with password pwd1 and salt salt1.
// Encrypt data1 with key k1 using symmetric encryption, creating edata1.
// Decrypt edata1 with key k2 using symmetric decryption, creating data2.
// data2 should equal data1.

int main()
{
   array<String^>^passwordargs = Environment::GetCommandLineArgs();
   String^ usageText = "Usage: RFC2898 <password>\nYou must specify the password for encryption.\n";

   //If no file name is specified, write usage text.
   if ( passwordargs->Length == 1 )
   {
      Console::WriteLine( usageText );
   }
   else
   {
      String^ pwd1 = passwordargs[ 1 ];
      
      array<Byte>^salt1 = gcnew array<Byte>(8);
	  RNGCryptoServiceProvider ^ rngCsp = gcnew RNGCryptoServiceProvider();
		 rngCsp->GetBytes(salt1);
      //data1 can be a string or contents of a file.
      String^ data1 = "Some test data";

      //The default iteration count is 1000 so the two methods use the same iteration count.
      int myIterations = 1000;

      try
      {
         Rfc2898DeriveBytes ^ k1 = gcnew Rfc2898DeriveBytes( pwd1,salt1,myIterations );
         Rfc2898DeriveBytes ^ k2 = gcnew Rfc2898DeriveBytes( pwd1,salt1 );

         // Encrypt the data.
         TripleDES^ encAlg = TripleDES::Create();
         encAlg->Key = k1->GetBytes( 16 );
         MemoryStream^ encryptionStream = gcnew MemoryStream;
         CryptoStream^ encrypt = gcnew CryptoStream( encryptionStream,encAlg->CreateEncryptor(),CryptoStreamMode::Write );
         array<Byte>^utfD1 = (gcnew System::Text::UTF8Encoding( false ))->GetBytes( data1 );

         encrypt->Write( utfD1, 0, utfD1->Length );
         encrypt->FlushFinalBlock();
         encrypt->Close();
         array<Byte>^edata1 = encryptionStream->ToArray();
         k1->Reset();

         // Try to decrypt, thus showing it can be round-tripped.
         TripleDES^ decAlg = TripleDES::Create();
         decAlg->Key = k2->GetBytes( 16 );
         decAlg->IV = encAlg->IV;
         MemoryStream^ decryptionStreamBacking = gcnew MemoryStream;
         CryptoStream^ decrypt = gcnew CryptoStream( decryptionStreamBacking,decAlg->CreateDecryptor(),CryptoStreamMode::Write );

         decrypt->Write( edata1, 0, edata1->Length );
         decrypt->Flush();
         decrypt->Close();
         k2->Reset();

         String^ data2 = (gcnew UTF8Encoding( false ))->GetString( decryptionStreamBacking->ToArray() );
         if (  !data1->Equals( data2 ) )
         {
            Console::WriteLine( "Error: The two values are not equal." );
         }
         else
         {
            Console::WriteLine( "The two values are equal." );
            Console::WriteLine( "k1 iterations: {0}", k1->IterationCount );
            Console::WriteLine( "k2 iterations: {0}", k2->IterationCount );
         }
      }

      catch ( Exception^ e ) 
      {
         Console::WriteLine( "Error: ", e );
      }
   }
}
using System;
using System.IO;
using System.Text;
using System.Security.Cryptography;

public class rfc2898test
{
    // Generate a key k1 with password pwd1 and salt salt1.
    // Generate a key k2 with password pwd1 and salt salt1.
    // Encrypt data1 with key k1 using symmetric encryption, creating edata1.
    // Decrypt edata1 with key k2 using symmetric decryption, creating data2.
    // data2 should equal data1.

    private const string usageText = "Usage: RFC2898 <password>\nYou must 
specify the password for encryption.\n";
    public static void Main(string[] passwordargs)
    {
        //If no file name is specified, write usage text.
        if (passwordargs.Length == 0)
        {
            Console.WriteLine(usageText);
        }
        else
        {
            string pwd1 = passwordargs[0];
            // Create a byte array to hold the random value. 
            byte[] salt1 = new byte[8];
            using (RNGCryptoServiceProvider rngCsp = new 
RNGCryptoServiceProvider())
            {
                // Fill the array with a random value.
                rngCsp.GetBytes(salt1);
            }

            //data1 can be a string or contents of a file.
            string data1 = "Some test data";
            //The default iteration count is 1000 so the two methods use the 
same iteration count.
            int myIterations = 1000;
            try
            {
                Rfc2898DeriveBytes k1 = new Rfc2898DeriveBytes(pwd1, salt1, 
myIterations);
                Rfc2898DeriveBytes k2 = new Rfc2898DeriveBytes(pwd1, salt1);
                // Encrypt the data.
                TripleDES encAlg = TripleDES.Create();
                encAlg.Key = k1.GetBytes(16);
                MemoryStream encryptionStream = new MemoryStream();
                CryptoStream encrypt = new CryptoStream(encryptionStream, 
encAlg.CreateEncryptor(), CryptoStreamMode.Write);
                byte[] utfD1 = new System.Text.UTF8Encoding(false).GetBytes(
data1);

                encrypt.Write(utfD1, 0, utfD1.Length);
                encrypt.FlushFinalBlock();
                encrypt.Close();
                byte[] edata1 = encryptionStream.ToArray();
                k1.Reset();

                // Try to decrypt, thus showing it can be round-tripped.
                TripleDES decAlg = TripleDES.Create();
                decAlg.Key = k2.GetBytes(16);
                decAlg.IV = encAlg.IV;
                MemoryStream decryptionStreamBacking = new MemoryStream();
                CryptoStream decrypt = new CryptoStream(
decryptionStreamBacking, decAlg.CreateDecryptor(), CryptoStreamMode.Write);
                decrypt.Write(edata1, 0, edata1.Length);
                decrypt.Flush();
                decrypt.Close();
                k2.Reset();
                string data2 = new UTF8Encoding(false).GetString(
decryptionStreamBacking.ToArray());

                if (!data1.Equals(data2))
                {
                    Console.WriteLine("Error: The two values are not equal.");
                }
                else
                {
                    Console.WriteLine("The two values are equal.");
                    Console.WriteLine("k1 iterations: {0}", k1.IterationCount);
                    Console.WriteLine("k2 iterations: {0}", k2.IterationCount);
                }
            }
            catch (Exception e)
            {
                Console.WriteLine("Error: ", e);
            }

        }
    }
}
Imports System
Imports System.IO
Imports System.Text
Imports System.Security.Cryptography



Public Class rfc2898test
    ' Generate a key k1 with password pwd1 and salt salt1.
    ' Generate a key k2 with password pwd1 and salt salt1.
    ' Encrypt data1 with key k1 using symmetric encryption, creating edata1.
    ' Decrypt edata1 with key k2 using symmetric decryption, creating data2.
    ' data2 should equal data1.
    Private Const usageText As String = "Usage: RFC2898 <password>" + vbLf + "You must specify the password for encryption." + vbLf

    Public Shared Sub Main(ByVal passwordargs() As String)
        'If no file name is specified, write usage text.
        If passwordargs.Length = 0 Then
            Console.WriteLine(usageText)
        Else
            Dim pwd1 As String = passwordargs(0)

            Dim salt1(8) As Byte
            Using rngCsp As New RNGCryptoServiceProvider()
                rngCsp.GetBytes(salt1)
            End Using
            'data1 can be a string or contents of a file.
            Dim data1 As String = "Some test data"
            'The default iteration count is 1000 so the two methods use the same iteration count.
            Dim myIterations As Integer = 1000
            Try
                Dim k1 As New Rfc2898DeriveBytes(pwd1, salt1, myIterations)
                Dim k2 As New Rfc2898DeriveBytes(pwd1, salt1)
                ' Encrypt the data.
                Dim encAlg As TripleDES = TripleDES.Create()
                encAlg.Key = k1.GetBytes(16)
                Dim encryptionStream As New MemoryStream()
                Dim encrypt As New CryptoStream(encryptionStream, encAlg.CreateEncryptor(), CryptoStreamMode.Write)
                Dim utfD1 As Byte() = New System.Text.UTF8Encoding(False).GetBytes(data1)
                encrypt.Write(utfD1, 0, utfD1.Length)
                encrypt.FlushFinalBlock()
                encrypt.Close()
                Dim edata1 As Byte() = encryptionStream.ToArray()
                k1.Reset()

                ' Try to decrypt, thus showing it can be round-tripped.
                Dim decAlg As TripleDES = TripleDES.Create()
                decAlg.Key = k2.GetBytes(16)
                decAlg.IV = encAlg.IV
                Dim decryptionStreamBacking As New MemoryStream()
                Dim decrypt As New CryptoStream(decryptionStreamBacking, decAlg.CreateDecryptor(), CryptoStreamMode.Write)
                decrypt.Write(edata1, 0, edata1.Length)
                decrypt.Flush()
                decrypt.Close()
                k2.Reset()
                Dim data2 As String = New UTF8Encoding(False).GetString(decryptionStreamBacking.ToArray())

                If Not data1.Equals(data2) Then
                    Console.WriteLine("Error: The two values are not equal.")
                Else
                    Console.WriteLine("The two values are equal.")
                    Console.WriteLine("k1 iterations: {0}", k1.IterationCount)
                    Console.WriteLine("k2 iterations: {0}", k2.IterationCount)
                End If
            Catch e As Exception
                Console.WriteLine("Error: ", e)
            End Try
        End If

    End Sub
End Class

Poznámky

Rfc2898DeriveBytesbere v hesle heslo, hodnotu Salt a počet iterací a potom generuje klíče prostřednictvím volání GetBytes metody.Rfc2898DeriveBytes takes a password, a salt, and an iteration count, and then generates keys through calls to the GetBytes method.

Dokument RFC 2898 obsahuje metody pro vytváření klíčového a inicializačního vektoru (IV) z hesla a soli.RFC 2898 includes methods for creating a key and initialization vector (IV) from a password and salt. Pro odvození klíčů pomocí funkce pseudo-Random, která umožňuje vygenerovat klíče prakticky neomezenou délku, můžete použít funkci odvození klíče PBKDF2 na základě hesla.You can use PBKDF2, a password-based key derivation function, to derive keys using a pseudo-random function that allows keys of virtually unlimited length to be generated. Rfc2898DeriveBytes Třída se dá použít k vytvoření odvozeného klíče ze základního klíče a dalších parametrů.The Rfc2898DeriveBytes class can be used to produce a derived key from a base key and other parameters. Ve funkci odvození klíče založené na hesle je základní klíč heslo a ostatní parametry jsou hodnota salt a počet iterací.In a password-based key derivation function, the base key is a password and the other parameters are a salt value and an iteration count.

Další informace o PBKDF2 najdete v dokumentu RFC 2898, "PKCS #5: Specifikace Kryptografie založená na heslech verze 2,0, "k dispozici na webu Request for Comments.For more information about PBKDF2, see RFC 2898, "PKCS #5: Password-Based Cryptography Specification Version 2.0," available on the Request for Comments Web site. Úplné podrobnosti najdete v části 5,2, "PBKDF2".See section 5.2, "PBKDF2," for complete details.

Důležité

Nikdy nepoužívejte pevně zakódování hesla v rámci zdrojového kódu.Never hard-code a password within your source code. Pevně zakódovaná hesla lze načíst ze sestavení pomocí nástroje Ildasm. exe (IL Disassembler), pomocí šestnáctkového editoru nebo pouhým otevřením sestavení v textovém editoru, jako je například Poznámkový blok. exe.Hard-coded passwords can be retrieved from an assembly by using the Ildasm.exe (IL Disassembler), by using a hexadecimal editor, or by simply opening up the assembly in a text editor such as Notepad.exe.

Konstruktory

Rfc2898DeriveBytes(Byte[], Byte[], Int32) Rfc2898DeriveBytes(Byte[], Byte[], Int32) Rfc2898DeriveBytes(Byte[], Byte[], Int32) Rfc2898DeriveBytes(Byte[], Byte[], Int32)

Inicializuje novou instanci Rfc2898DeriveBytes třídy pomocí hesla, soli a počtu iterací pro odvození klíče.Initializes a new instance of the Rfc2898DeriveBytes class using a password, a salt, and number of iterations to derive the key.

Rfc2898DeriveBytes(Byte[], Byte[], Int32, HashAlgorithmName) Rfc2898DeriveBytes(Byte[], Byte[], Int32, HashAlgorithmName) Rfc2898DeriveBytes(Byte[], Byte[], Int32, HashAlgorithmName) Rfc2898DeriveBytes(Byte[], Byte[], Int32, HashAlgorithmName)

Inicializuje novou instanci Rfc2898DeriveBytes třídy pomocí zadaného hesla, soli, počtu iterací a názvu algoritmu hash pro odvození klíče.Initializes a new instance of the Rfc2898DeriveBytes class using the specified password, salt, number of iterations and the hash algorithm name to derive the key.

Rfc2898DeriveBytes(String, Byte[]) Rfc2898DeriveBytes(String, Byte[]) Rfc2898DeriveBytes(String, Byte[]) Rfc2898DeriveBytes(String, Byte[])

Inicializuje novou instanci Rfc2898DeriveBytes třídy pomocí hesla a příměsi pro odvození klíče.Initializes a new instance of the Rfc2898DeriveBytes class using a password and salt to derive the key.

Rfc2898DeriveBytes(String, Byte[], Int32) Rfc2898DeriveBytes(String, Byte[], Int32) Rfc2898DeriveBytes(String, Byte[], Int32) Rfc2898DeriveBytes(String, Byte[], Int32)

Inicializuje novou instanci Rfc2898DeriveBytes třídy pomocí hesla, soli a počtu iterací pro odvození klíče.Initializes a new instance of the Rfc2898DeriveBytes class using a password, a salt, and number of iterations to derive the key.

Rfc2898DeriveBytes(String, Byte[], Int32, HashAlgorithmName) Rfc2898DeriveBytes(String, Byte[], Int32, HashAlgorithmName) Rfc2898DeriveBytes(String, Byte[], Int32, HashAlgorithmName) Rfc2898DeriveBytes(String, Byte[], Int32, HashAlgorithmName)

Inicializuje novou instanci Rfc2898DeriveBytes třídy pomocí zadaného hesla, soli, počtu iterací a názvu algoritmu hash pro odvození klíče.Initializes a new instance of the Rfc2898DeriveBytes class using the specified password, salt, number of iterations and the hash algorithm name to derive the key.

Rfc2898DeriveBytes(String, Int32) Rfc2898DeriveBytes(String, Int32) Rfc2898DeriveBytes(String, Int32) Rfc2898DeriveBytes(String, Int32)

Inicializuje novou instanci Rfc2898DeriveBytes třídy pomocí hesla a velikosti soli pro odvození klíče.Initializes a new instance of the Rfc2898DeriveBytes class using the password and salt size to derive the key.

Rfc2898DeriveBytes(String, Int32, Int32) Rfc2898DeriveBytes(String, Int32, Int32) Rfc2898DeriveBytes(String, Int32, Int32) Rfc2898DeriveBytes(String, Int32, Int32)

Inicializuje novou instanci Rfc2898DeriveBytes třídy pomocí hesla, velikosti soli a počtu iterací pro odvození klíče.Initializes a new instance of the Rfc2898DeriveBytes class using a password, a salt size, and number of iterations to derive the key.

Rfc2898DeriveBytes(String, Int32, Int32, HashAlgorithmName) Rfc2898DeriveBytes(String, Int32, Int32, HashAlgorithmName) Rfc2898DeriveBytes(String, Int32, Int32, HashAlgorithmName) Rfc2898DeriveBytes(String, Int32, Int32, HashAlgorithmName)

Inicializuje novou instanci Rfc2898DeriveBytes třídy pomocí zadaného hesla, velikosti soli, počtu iterací a názvu algoritmu hash pro odvození klíče.Initializes a new instance of the Rfc2898DeriveBytes class using the specified password, salt size, number of iterations and the hash algorithm name to derive the key.

Vlastnosti

HashAlgorithm HashAlgorithm HashAlgorithm HashAlgorithm
IterationCount IterationCount IterationCount IterationCount

Získá nebo nastaví počet iterací pro operaci.Gets or sets the number of iterations for the operation.

Salt Salt Salt Salt

Získá nebo nastaví hodnotu hodnoty salt klíče pro operaci.Gets or sets the key salt value for the operation.

Metody

CryptDeriveKey(String, String, Int32, Byte[]) CryptDeriveKey(String, String, Int32, Byte[]) CryptDeriveKey(String, String, Int32, Byte[]) CryptDeriveKey(String, String, Int32, Byte[])

Odvodí kryptografický klíč z Rfc2898DeriveBytes objektu.Derives a cryptographic key from the Rfc2898DeriveBytes object.

Dispose() Dispose() Dispose() Dispose()

Při přepsání v odvozené třídě uvolní všechny prostředky používané aktuální instancí DeriveBytes třídy.When overridden in a derived class, releases all resources used by the current instance of the DeriveBytes class.

(Inherited from DeriveBytes)
Dispose(Boolean) Dispose(Boolean) Dispose(Boolean) Dispose(Boolean)

Uvolní nespravované prostředky používané Rfc2898DeriveBytes třídou a volitelně uvolňuje spravované prostředky.Releases the unmanaged resources used by the Rfc2898DeriveBytes class and optionally releases the managed resources.

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)
GetBytes(Int32) GetBytes(Int32) GetBytes(Int32) GetBytes(Int32)

Vrátí pseudo-náhodný klíč pro tento objekt.Returns the pseudo-random key for this object.

GetHashCode() GetHashCode() GetHashCode() GetHashCode()

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

(Inherited from Object)
GetType() GetType() GetType() GetType()

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

(Inherited from Object)
MemberwiseClone() MemberwiseClone() MemberwiseClone() MemberwiseClone()

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

(Inherited from Object)
Reset() Reset() Reset() Reset()

Obnoví stav operace.Resets the state of the operation.

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

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

(Inherited from Object)

Platí pro

Viz také