RSACryptoServiceProvider.VerifyHash メソッド

[アーティクル]
03/28/2008

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。

Public Function VerifyHash( _
   ByVal rgbHash() As Byte, _   ByVal str As String, _   ByVal rgbSignature() As Byte _) As Boolean
[C#]
public bool VerifyHash(byte[] rgbHash,stringstr,byte[] rgbSignature);
[C++]
public: bool VerifyHash(unsigned charrgbHash __gc[],String* str,unsigned charrgbSignature __gc[]);
[JScript]
public function VerifyHash(
   rgbHash : Byte[],str : String,rgbSignature : Byte[]) : Boolean;

パラメータ

rgbHash
署名されるデータのハッシュ値。
str
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
検証される署名データ。

戻り値

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

例外の種類	条件
ArgumentNullException	rgbHash パラメータが null 参照 (Visual Basic では Nothing) です。または rgbSignature パラメータが null 参照 (Nothing) です。
CryptographicException	暗号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。

ArgumentNullException

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

または

rgbSignature パラメータが null 参照 (Nothing) です。

CryptographicException

暗号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。

使用例

 
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

[C#] 
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);
        }
    }
}

[C++] 
#using <mscorlib.dll>
#using <System.dll>

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

__gc class Sender {
private:
    RSAParameters rsaPubParams;
    RSAParameters rsaPrivateParams;

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

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

    __property RSAParameters get_PublicParameters() {
        return rsaPubParams;
    }

    //Manually performs hash and then signs hashed value.
    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(S"SHA1"));
    }

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

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

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

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

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

    __property RSAParameters get_PublicParameters() {
        return rsaPubParams;
    }

    //Manually performs hash and then verifies hashed value.
    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(S"SHA1"), signature);
    }

    //Decrypt using the private key data.
    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(S"RoundTrip: {0}", roundTrip);
    }
};

int main() {
    Byte toEncrypt[];
    Byte encrypted[];
    Byte signature[];
    //Choose a small amount of data to encrypt.
    String* original = S"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(S"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(S"Invalid signature");
    }
}

[JScript] JScript のサンプルはありません。Visual Basic、C#、および C++ のサンプルを表示するには、このページの左上隅にある言語のフィルタボタンをクリックします。

必要条件

プラットフォーム: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 ファミリ

参照

RSACryptoServiceProvider クラス | RSACryptoServiceProvider メンバ | System.Security.Cryptography 名前空間 | 暗号サービス

次の方法で共有

RSACryptoServiceProvider.VerifyHash メソッド

パラメータ

戻り値

例外

解説

使用例

必要条件

参照

その他のリソース