RSACryptoServiceProvider.SignData メソッド (Stream, Object)
指定したハッシュ アルゴリズムを使用して、指定した入力ストリームのハッシュ値を計算し、結果ハッシュ値に署名します。
Overloads Public Function SignData( _
ByVal inputStream As Stream, _ ByVal halg As Object _) As Byte()
[C#]
public byte[] SignData(StreaminputStream,objecthalg);
[C++]
public: unsigned char SignData(Stream* inputStream,Object* halg) __gc[];
[JScript]
public function SignData(
inputStream : Stream,halg : Object) : Byte[];
パラメータ
- inputStream
ハッシュを計算する対象の入力データ。 - halg
ハッシュ値の作成に使用するハッシュ アルゴリズム。
戻り値
指定したデータの RSA 署名。
例外
| 例外の種類 | 条件 |
|---|---|
| ArgumentNullException | halg パラメータが null 参照 (Visual Basic では Nothing) です。 |
| ArgumentException | halg パラメータの型が有効ではありません。 |
解説
halg パラメータには、 String 、 HashAlgorithm 、または Type を使用できます。
使用例
[Visual Basic, C#] SignData メソッドを使用する方法を次の例に示します。
Imports System.Security.Cryptography
Imports System.Text
Imports System.IO
Module RSACSPExample
Sub Main()
Try
Dim ByteConverter As New ASCIIEncoding
' Create some bytes to be signed.
Dim dataBytes As Byte() = ByteConverter.GetBytes("Here is some data to sign!")
' Create a buffer for the memory stream.
' VB automatically pads arrays with an extra
' Digit of "0".
' RSACryptoServiceProvider will not verify
' the buffer if the automatic padding is
' present. To remove the padding, decrement
' the buffer length by 1.
Dim buffer(dataBytes.Length - 1) As Byte
' Create a MemoryStream.
Dim mStream As New MemoryStream(buffer)
' Write the bytes to the stream and flush it.
mStream.Write(dataBytes, 0, dataBytes.Length)
mStream.Flush()
' Create a new instance of the RSACryptoServiceProvider class
' and automatically create a new key-pair.
Dim RSAalg As New RSACryptoServiceProvider
' Export the key information to an RSAParameters object.
' You must pass true to export the private key for signing.
' However, you do not need to export the private key
' for verification.
Dim Key As RSAParameters = RSAalg.ExportParameters(True)
' Hash and sign the data.
Dim signedData As Byte() = HashAndSignBytes(mStream, Key)
' Verify the data and display the result to the
' console.
If VerifySignedHash(dataBytes, signedData, Key) Then
Console.WriteLine("The data was verified.")
Else
Console.WriteLine("The data does not match the signature.")
End If
' Close the MemoryStream.
mStream.Close()
Catch e As ArgumentNullException
Console.WriteLine("The data was not signed or verified")
End Try
End Sub
Function HashAndSignBytes(ByVal DataStream As Stream, ByVal Key As RSAParameters) As Byte()
Try
' Reset the current position in the stream to
' the beginning of the stream (0). RSACryptoServiceProvider
' can't verify the data unless the the stream position
' is set to the starting position of the data.
DataStream.Position = 0
' Create a new instance of RSACryptoServiceProvider using the
' key from RSAParameters.
Dim RSAalg As New RSACryptoServiceProvider
RSAalg.ImportParameters(Key)
' Hash and sign the data. Pass a new instance of SHA1CryptoServiceProvider
' to specify the use of SHA1 for hashing.
Return RSAalg.SignData(DataStream, New SHA1CryptoServiceProvider)
Catch e As CryptographicException
Console.WriteLine(e.Message)
Return Nothing
End Try
End Function
Function VerifySignedHash(ByVal DataToVerify() As Byte, ByVal SignedData() As Byte, ByVal Key As RSAParameters) As Boolean
Try
' Create a new instance of RSACryptoServiceProvider using the
' key from RSAParameters.
Dim RSAalg As New RSACryptoServiceProvider
RSAalg.ImportParameters(Key)
' Verify the data using the signature. Pass a new instance of SHA1CryptoServiceProvider
' to specify the use of SHA1 for hashing.
Return RSAalg.VerifyData(DataToVerify, New SHA1CryptoServiceProvider, SignedData)
Catch e As CryptographicException
Console.WriteLine(e.Message)
Return False
End Try
End Function
End Module
[C#]
using System;
using System.Security.Cryptography;
using System.Text;
using System.IO;
class RSACSPSample
{
static void Main()
{
try
{
ASCIIEncoding ByteConverter = new ASCIIEncoding();
// Create some bytes to be signed.
byte[] dataBytes = ByteConverter.GetBytes("Here is some data to sign!");
// Create a buffer for the memory stream.
byte[] buffer = new byte[dataBytes.Length];
// Create a MemoryStream.
MemoryStream mStream = new MemoryStream(buffer);
// Write the bytes to the stream and flush it.
mStream.Write(dataBytes, 0, dataBytes.Length);
mStream.Flush();
// Create a new instance of the RSACryptoServiceProvider class
// and automatically create a new key-pair.
RSACryptoServiceProvider RSAalg = new RSACryptoServiceProvider();
// Export the key information to an RSAParameters object.
// You must pass true to export the private key for signing.
// However, you do not need to export the private key
// for verification.
RSAParameters Key = RSAalg.ExportParameters(true);
// Hash and sign the data.
byte[] signedData = HashAndSignBytes(mStream, Key);
// Verify the data and display the result to the
// console.
if(VerifySignedHash(dataBytes, signedData, Key))
{
Console.WriteLine("The data was verified.");
}
else
{
Console.WriteLine("The data does not match the signature.");
}
// Close the MemoryStream.
mStream.Close();
}
catch(ArgumentNullException)
{
Console.WriteLine("The data was not signed or verified");
}
}
public static byte[] HashAndSignBytes(Stream DataStream, RSAParameters Key)
{
try
{
// Reset the current position in the stream to
// the beginning of the stream (0). RSACryptoServiceProvider
// can't verify the data unless the the stream position
// is set to the starting position of the data.
DataStream.Position = 0;
// Create a new instance of RSACryptoServiceProvider using the
// key from RSAParameters.
RSACryptoServiceProvider RSAalg = new RSACryptoServiceProvider();
RSAalg.ImportParameters(Key);
// Hash and sign the data. Pass a new instance of SHA1CryptoServiceProvider
// to specify the use of SHA1 for hashing.
return RSAalg.SignData(DataStream, new SHA1CryptoServiceProvider());
}
catch(CryptographicException e)
{
Console.WriteLine(e.Message);
return null;
}
}
public static bool VerifySignedHash(byte[] DataToVerify, byte[] SignedData, RSAParameters Key)
{
try
{
// Create a new instance of RSACryptoServiceProvider using the
// key from RSAParameters.
RSACryptoServiceProvider RSAalg = new RSACryptoServiceProvider();
RSAalg.ImportParameters(Key);
// Verify the data using the signature. Pass a new instance of SHA1CryptoServiceProvider
// to specify the use of SHA1 for hashing.
return RSAalg.VerifyData(DataToVerify, new SHA1CryptoServiceProvider(), SignedData);
}
catch(CryptographicException e)
{
Console.WriteLine(e.Message);
return false;
}
}
}
[C++, JScript] C++ および JScript のサンプルはありません。Visual Basic 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 .gif)
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 | RSACryptoServiceProvider.SignData オーバーロードの一覧 | 暗号サービス