RSACryptoServiceProvider.VerifyHash メソッド (System.Security.Cryptography)

.NET Framework クラスライブラリ

RSACryptoServiceProvider..::.VerifyHash メソッド

更新 : 2007 年 11 月

指定した署名データを、指定したハッシュ値に対して計算された署名と比較することによって検証します。

名前空間 : System.Security.Cryptography
アセンブリ : mscorlib (mscorlib.dll 内)

構文

Visual Basic (宣言)

Public Function VerifyHash ( _
    rgbHash As Byte(), _
    str As String, _
    rgbSignature As Byte() _
) As Boolean

Visual Basic (使用法)

Dim instance As RSACryptoServiceProvider
Dim rgbHash As Byte()
Dim str As String
Dim rgbSignature As Byte()
Dim returnValue As Boolean

returnValue = instance.VerifyHash(rgbHash, _
    str, rgbSignature)

public bool VerifyHash(
    byte[] rgbHash,
    string str,
    byte[] rgbSignature
)

Visual C++

public:
bool VerifyHash(
    array<unsigned char>^ rgbHash, 
    String^ str, 
    array<unsigned char>^ rgbSignature
)

public boolean VerifyHash(
    byte[] rgbHash,
    String str,
    byte[] rgbSignature
)

JScript

public function VerifyHash(
    rgbHash : byte[], 
    str : String, 
    rgbSignature : byte[]
) : boolean

パラメータ

rgbHash: 型 : array<System..::.Byte>[]()[]
署名されるデータのハッシュ値。

str: 型 : System..::.String
データのハッシュ値の作成に使用するハッシュアルゴリズム識別子 (OID)。

rgbSignature: 型 : array<System..::.Byte>[]()[]
検証される署名データ。

戻り値

型 : System..::.Boolean

検証の結果、署名が有効な場合は true。それ以外の場合は false。

例外

例外	条件
ArgumentNullException	rgbHash パラメータが nullNothingnullptrnull 参照 (Visual Basic では Nothing) です。または rgbSignature パラメータが nullNothingnullptrnull 参照 (Visual Basic では Nothing) です。
CryptographicException	暗号化サービスプロバイダ (CSP) を取得できません。または署名を検証できません。

条件

ArgumentNullException

rgbHash パラメータが nullNothingnullptrnull 参照 (Visual Basic では Nothing) です。

または

rgbSignature パラメータが nullNothingnullptrnull 参照 (Visual Basic では Nothing) です。

CryptographicException

暗号化サービスプロバイダ (CSP) を取得できません。

または

署名を検証できません。

解説

このメソッドは、SignHash によって生成された RSA デジタル署名を検証します。

有効なハッシュアルゴリズムは SHA1 と MD5 です。アルゴリズム識別子は、MapNameToOID メソッドを使用して、ハッシュ名から取得できます。

例

一部のデータを暗号化し、暗号化データのハッシュを作成して、そのハッシュにデジタル署名で署名するコード例を次に示します。

Visual Basic

Imports System
Imports System.Text
Imports System.Security.Cryptography

Namespace RSACryptoServiceProvider_Examples
    Class MyMainClass
        Shared Sub Main()
            Dim toEncrypt() As Byte
            Dim encrypted() As Byte
            Dim signature() As Byte
            'Choose a small amount of data to encrypt.
            Dim original As String = "Hello"
            Dim myAscii As New ASCIIEncoding()

            'Create a sender and receiver.
            Dim mySender As New Sender()
            Dim myReceiver As New Receiver()

            'Convert the data string to a byte array.
            toEncrypt = myAscii.GetBytes(original)

            'Encrypt data using receiver's public key.
            encrypted = mySender.EncryptData(myReceiver.PublicParameters, toEncrypt)

            'Hash the encrypted data and generate a signature on the hash
            ' using the sender's private key.
            signature = mySender.HashAndSign(encrypted)

            Console.WriteLine("Original: {0}", original)

            'Verify the signature is authentic using the sender's public key.
            If myReceiver.VerifyHash(mySender.PublicParameters, encrypted, signature) Then
                'Decrypt the data using the receiver's private key.
                myReceiver.DecryptData(encrypted)
            Else
                Console.WriteLine("Invalid signature")
            End If
        End Sub 'Main
    End Class 'MyMainClass

    Class Sender
        Private rsaPubParams As RSAParameters
        Private rsaPrivateParams As RSAParameters

        Public Sub New()
            Dim rsaCSP As New RSACryptoServiceProvider()

            'Generate public and private key data.
            rsaPrivateParams = rsaCSP.ExportParameters(True)
            rsaPubParams = rsaCSP.ExportParameters(False)
        End Sub 'New

        Public ReadOnly Property PublicParameters() As RSAParameters
            Get
                Return rsaPubParams
            End Get
        End Property

        'Manually performs hash and then signs hashed value.
        Public Function HashAndSign(ByVal encrypted() As Byte) As Byte()
            Dim rsaCSP As New RSACryptoServiceProvider()
            Dim hash As New SHA1Managed()
            Dim hashedData() As Byte

            rsaCSP.ImportParameters(rsaPrivateParams)

            hashedData = hash.ComputeHash(encrypted)
            Return rsaCSP.SignHash(hashedData, CryptoConfig.MapNameToOID("SHA1"))
        End Function 'HashAndSign

        'Encrypts using only the public key data.
        Public Function EncryptData(ByVal rsaParams As RSAParameters, ByVal toEncrypt() As Byte) As Byte()
            Dim rsaCSP As New RSACryptoServiceProvider()

            rsaCSP.ImportParameters(rsaParams)
            Return rsaCSP.Encrypt(toEncrypt, False)
        End Function 'EncryptData
    End Class 'Sender

    Class Receiver
        Private rsaPubParams As RSAParameters
        Private rsaPrivateParams As RSAParameters

        Public Sub New()
            Dim rsaCSP As New RSACryptoServiceProvider()

            'Generate public and private key data.
            rsaPrivateParams = rsaCSP.ExportParameters(True)
            rsaPubParams = rsaCSP.ExportParameters(False)
        End Sub 'New

        Public ReadOnly Property PublicParameters() As RSAParameters
            Get
                Return rsaPubParams
            End Get
        End Property

        'Manually performs hash and then verifies hashed value.
        Public Function VerifyHash(ByVal rsaParams As RSAParameters, ByVal signedData() As Byte, ByVal signature() As Byte) As Boolean
            Dim rsaCSP As New RSACryptoServiceProvider()
            Dim hash As New SHA1Managed()
            Dim hashedData() As Byte

            rsaCSP.ImportParameters(rsaParams)

            hashedData = hash.ComputeHash(signedData)
            Return rsaCSP.VerifyHash(hashedData, CryptoConfig.MapNameToOID("SHA1"), signature)
        End Function 'VerifyHash

        'Decrypt using the private key data.
        Public Sub DecryptData(ByVal encrypted() As Byte)
            Dim fromEncrypt() As Byte
            Dim roundTrip As String
            Dim myAscii As New ASCIIEncoding()
            Dim rsaCSP As New RSACryptoServiceProvider()

            rsaCSP.ImportParameters(rsaPrivateParams)
            fromEncrypt = rsaCSP.Decrypt(encrypted, False)
            roundTrip = myAscii.GetString(fromEncrypt)

            Console.WriteLine("RoundTrip: {0}", roundTrip)
        End Sub 'DecryptData
    End Class 'Receiver
End Namespace 'RSACryptoServiceProvider_Examples

using System;
using System.Text;
using System.Security.Cryptography;

namespace RSACryptoServiceProvider_Examples
{
    class MyMainClass
    {
        static void Main()
        {
            byte[] toEncrypt;
            byte[] encrypted;
            byte[] signature;
            //Choose a small amount of data to encrypt.
            string original = "Hello";
            ASCIIEncoding myAscii = new ASCIIEncoding();

            //Create a sender and receiver.
            Sender mySender = new Sender();
            Receiver myReceiver = new Receiver();

            //Convert the data string to a byte array.
            toEncrypt = myAscii.GetBytes(original);

            //Encrypt data using receiver's public key.
            encrypted = mySender.EncryptData(myReceiver.PublicParameters, toEncrypt);

            //Hash the encrypted data and generate a signature on the hash
            // using the sender's private key.
            signature = mySender.HashAndSign(encrypted);

            Console.WriteLine("Original: {0}", original);

            //Verify the signature is authentic using the sender's public key.
            if(myReceiver.VerifyHash(mySender.PublicParameters, encrypted, signature))
            {
                //Decrypt the data using the receiver's private key.
                myReceiver.DecryptData(encrypted);
            }
            else
            {
                Console.WriteLine("Invalid signature");
            }
        }
    }

    class Sender
    {
        RSAParameters rsaPubParams;
        RSAParameters rsaPrivateParams;

        public Sender()
        {
            RSACryptoServiceProvider rsaCSP = new RSACryptoServiceProvider();

            //Generate public and private key data.
            rsaPrivateParams = rsaCSP.ExportParameters(true);
            rsaPubParams = rsaCSP.ExportParameters(false);
        }

        public RSAParameters PublicParameters
        {
            get
            {
                return rsaPubParams;
            }
        }

        //Manually performs hash and then signs hashed value.
        public byte[] HashAndSign(byte[] encrypted)
        {
            RSACryptoServiceProvider rsaCSP = new RSACryptoServiceProvider();
            SHA1Managed hash = new SHA1Managed();
            byte[] hashedData;

            rsaCSP.ImportParameters(rsaPrivateParams);

            hashedData = hash.ComputeHash(encrypted);
            return rsaCSP.SignHash(hashedData, CryptoConfig.MapNameToOID("SHA1"));
        }

        //Encrypts using only the public key data.
        public byte[] EncryptData(RSAParameters rsaParams, byte[] toEncrypt)
        {
            RSACryptoServiceProvider rsaCSP = new RSACryptoServiceProvider();

            rsaCSP.ImportParameters(rsaParams);
            return rsaCSP.Encrypt(toEncrypt, false);
        }
    }

    class Receiver
    {
        RSAParameters rsaPubParams;
        RSAParameters rsaPrivateParams;

        public Receiver()
        {
            RSACryptoServiceProvider rsaCSP = new RSACryptoServiceProvider();

            //Generate public and private key data.
            rsaPrivateParams = rsaCSP.ExportParameters(true);
            rsaPubParams = rsaCSP.ExportParameters(false);
        }

        public RSAParameters PublicParameters
        {
            get
            {
                return rsaPubParams;
            }
        }

        //Manually performs hash and then verifies hashed value.
        public bool VerifyHash(RSAParameters rsaParams, byte[] signedData, byte[] signature)
        {
            RSACryptoServiceProvider rsaCSP = new RSACryptoServiceProvider();
            SHA1Managed hash = new SHA1Managed();
            byte[] hashedData;

            rsaCSP.ImportParameters(rsaParams);

            hashedData = hash.ComputeHash(signedData);
            return rsaCSP.VerifyHash(hashedData, CryptoConfig.MapNameToOID("SHA1"), signature);
        }

        //Decrypt using the private key data.
        public void DecryptData(byte[] encrypted)
        {
            byte[] fromEncrypt;
            string roundTrip;
            ASCIIEncoding myAscii = new ASCIIEncoding();
            RSACryptoServiceProvider rsaCSP = new RSACryptoServiceProvider();

            rsaCSP.ImportParameters(rsaPrivateParams);
            fromEncrypt = rsaCSP.Decrypt(encrypted, false);
            roundTrip = myAscii.GetString(fromEncrypt);

            Console.WriteLine("RoundTrip: {0}", roundTrip);
        }
    }
}

Visual C++

#using <System.dll>

using namespace System;
using namespace System::Text;
using namespace System::Security::Cryptography;
ref class Sender
{
private:
   RSAParameters rsaPubParams;
   RSAParameters rsaPrivateParams;

public:
   Sender()
   {
      RSACryptoServiceProvider^ rsaCSP = gcnew RSACryptoServiceProvider;

      //Generate public and private key data.
      rsaPrivateParams = rsaCSP->ExportParameters( true );
      rsaPubParams = rsaCSP->ExportParameters( false );
   }


   property RSAParameters PublicParameters 
   {
      RSAParameters get()
      {
         return rsaPubParams;
      }

   }

   //Manually performs hash and then signs hashed value.
   array<Byte>^ HashAndSign( array<Byte>^encrypted )
   {
      RSACryptoServiceProvider^ rsaCSP = gcnew RSACryptoServiceProvider;
      SHA1Managed^ hash = gcnew SHA1Managed;
      array<Byte>^hashedData;
      rsaCSP->ImportParameters( rsaPrivateParams );
      hashedData = hash->ComputeHash( encrypted );
      return rsaCSP->SignHash( hashedData, CryptoConfig::MapNameToOID( "SHA1" ) );
   }


   //Encrypts using only the public key data.
   array<Byte>^ EncryptData( RSAParameters rsaParams, array<Byte>^toEncrypt )
   {
      RSACryptoServiceProvider^ rsaCSP = gcnew RSACryptoServiceProvider;
      rsaCSP->ImportParameters( rsaParams );
      return rsaCSP->Encrypt( toEncrypt, false );
   }

};

ref class Receiver
{
private:
   RSAParameters rsaPubParams;
   RSAParameters rsaPrivateParams;

public:
   Receiver()
   {
      RSACryptoServiceProvider^ rsaCSP = gcnew RSACryptoServiceProvider;

      //Generate public and private key data.
      rsaPrivateParams = rsaCSP->ExportParameters( true );
      rsaPubParams = rsaCSP->ExportParameters( false );
   }


   property RSAParameters PublicParameters 
   {
      RSAParameters get()
      {
         return rsaPubParams;
      }

   }

   //Manually performs hash and then verifies hashed value.
   bool VerifyHash( RSAParameters rsaParams, array<Byte>^signedData, array<Byte>^signature )
   {
      RSACryptoServiceProvider^ rsaCSP = gcnew RSACryptoServiceProvider;
      SHA1Managed^ hash = gcnew SHA1Managed;
      array<Byte>^hashedData;
      rsaCSP->ImportParameters( rsaParams );
      hashedData = hash->ComputeHash( signedData );
      return rsaCSP->VerifyHash( hashedData, CryptoConfig::MapNameToOID( "SHA1" ), signature );
   }


   //Decrypt using the private key data.
   void DecryptData( array<Byte>^encrypted )
   {
      array<Byte>^fromEncrypt;
      String^ roundTrip;
      ASCIIEncoding^ myAscii = gcnew ASCIIEncoding;
      RSACryptoServiceProvider^ rsaCSP = gcnew RSACryptoServiceProvider;
      rsaCSP->ImportParameters( rsaPrivateParams );
      fromEncrypt = rsaCSP->Decrypt( encrypted, false );
      roundTrip = myAscii->GetString( fromEncrypt );
      Console::WriteLine( "RoundTrip: {0}", roundTrip );
   }

};

int main()
{
   array<Byte>^toEncrypt;
   array<Byte>^encrypted;
   array<Byte>^signature;

   //Choose a small amount of data to encrypt.
   String^ original = "Hello";
   ASCIIEncoding^ myAscii = gcnew ASCIIEncoding;

   //Create a sender and receiver.
   Sender^ mySender = gcnew Sender;
   Receiver^ myReceiver = gcnew Receiver;

   //Convert the data string to a byte array.
   toEncrypt = myAscii->GetBytes( original );

   //Encrypt data using receiver's public key.
   encrypted = mySender->EncryptData( myReceiver->PublicParameters, toEncrypt );

   //Hash the encrypted data and generate a signature on the hash
   // using the sender's private key.
   signature = mySender->HashAndSign( encrypted );
   Console::WriteLine( "Original: {0}", original );

   //Verify the signature is authentic using the sender's public key.
   if ( myReceiver->VerifyHash( mySender->PublicParameters, encrypted, signature ) )
   {

      //Decrypt the data using the receiver's private key.
      myReceiver->DecryptData( encrypted );
   }
   else
   {
      Console::WriteLine( "Invalid signature" );
   }
}

package RSACryptoServiceProvider_Examples; 

import System.*;
import System.Text.*;
import System.Security.Cryptography.*;

class MyMainClass
{
    public static void main(String[] args)
    {
        ubyte toEncrypt[];
        ubyte encrypted[];
        ubyte signature[];

        // Choose a small amount of data to encrypt.
        String original = "Hello";
        ASCIIEncoding myAscii = new ASCIIEncoding();

        // Create a sender and receiver.
        Sender mySender = new Sender();
        Receiver myReceiver = new Receiver();

        // Convert the data string to a byte array.
        toEncrypt = myAscii.GetBytes(original);

        // Encrypt data using receiver's public key.
        encrypted = mySender.EncryptData(myReceiver.get_PublicParameters(),
            toEncrypt);

        // Hash the encrypted data and generate a signature on the hash
        // using the sender's private key.
        signature = mySender.HashAndSign(encrypted);
        Console.WriteLine("Original: {0}", original);

        // Verify the signature is authentic using the sender's public key.
        if (myReceiver.VerifyHash(mySender.get_PublicParameters(), 
                encrypted, signature)) {
            // Decrypt the data using the receiver's private key.
            myReceiver.DecryptData(encrypted);
        }
        else {
            Console.WriteLine("Invalid signature");
        }
    } //main
} //MyMainClass

class Sender
{
    private RSAParameters rsaPubParams;
    private RSAParameters rsaPrivateParams;

    public Sender()
    {
        RSACryptoServiceProvider rsaCSP = new RSACryptoServiceProvider();

        // Generate public and private key data.
        rsaPrivateParams = rsaCSP.ExportParameters(true);
        rsaPubParams = rsaCSP.ExportParameters(false);
    } //Sender

    /** @property 
     */
    public RSAParameters get_PublicParameters()
    {
        return rsaPubParams;
    } //get_PublicParameters

    // Manually performs hash and then signs hashed value.
    public ubyte[] HashAndSign(ubyte encrypted[])
    {
        RSACryptoServiceProvider rsaCSP = new RSACryptoServiceProvider();
        SHA1Managed hash = new SHA1Managed();
        ubyte hashedData[];

        rsaCSP.ImportParameters(rsaPrivateParams);
        hashedData = hash.ComputeHash(encrypted);
        return rsaCSP.SignHash(hashedData, CryptoConfig.MapNameToOID("SHA1"));
    } //HashAndSign

    // Encrypts using only the public key data.
    public ubyte[] EncryptData(RSAParameters rsaParams, ubyte toEncrypt[])
    {
        RSACryptoServiceProvider rsaCSP = new RSACryptoServiceProvider();

        rsaCSP.ImportParameters(rsaParams);
        return rsaCSP.Encrypt(toEncrypt, false);
    } //EncryptData
} //Sender

class Receiver
{
    private RSAParameters rsaPubParams;
    private RSAParameters rsaPrivateParams;

    public Receiver()
    {
        RSACryptoServiceProvider rsaCSP = new RSACryptoServiceProvider();

        // Generate public and private key data.
        rsaPrivateParams = rsaCSP.ExportParameters(true);
        rsaPubParams = rsaCSP.ExportParameters(false);
    } //Receiver

    /** @property 
     */
    public RSAParameters get_PublicParameters()
    {
        return rsaPubParams;
    } //get_PublicParameters

    // Manually performs hash and then verifies hashed value.
    public boolean VerifyHash(RSAParameters rsaParams, 
        ubyte signedData[], ubyte signature[])
    {
        RSACryptoServiceProvider rsaCSP = new RSACryptoServiceProvider();
        SHA1Managed hash = new SHA1Managed();
        ubyte hashedData[];

        rsaCSP.ImportParameters(rsaParams);
        hashedData = hash.ComputeHash(signedData);
        return rsaCSP.VerifyHash(hashedData, 
            CryptoConfig.MapNameToOID("SHA1"), signature);
    } //VerifyHash

    // Decrypt using the private key data.
    public void DecryptData(ubyte encrypted[])
    {
        ubyte fromEncrypt[];
        String roundTrip;
        ASCIIEncoding myAscii = new ASCIIEncoding();
        RSACryptoServiceProvider rsaCSP = new RSACryptoServiceProvider();

        rsaCSP.ImportParameters(rsaPrivateParams);
        fromEncrypt = rsaCSP.Decrypt(encrypted, false);
        roundTrip = myAscii.GetString(fromEncrypt);

        Console.WriteLine("RoundTrip: {0}", roundTrip);
    } //DecryptData
} //Receiver

プラットフォーム

Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC

.NET Framework および .NET Compact Framework では、各プラットフォームのすべてのバージョンはサポートしていません。サポートされているバージョンについては、「.NET Framework システム要件」を参照してください。

バージョン情報

.NET Framework

サポート対象 : 3.5、3.0、2.0、1.1、1.0

.NET Compact Framework

サポート対象 : 3.5、2.0

参照

RSACryptoServiceProvider クラス

RSACryptoServiceProvider メンバ

System.Security.Cryptography 名前空間

その他の技術情報

暗号サービス