RSACryptoServiceProvider.SignData Método
Definição
Importante
Algumas informações se referem a produtos de pré-lançamento que podem ser substancialmente modificados antes do lançamento. A Microsoft não oferece garantias, expressas ou implícitas, das informações aqui fornecidas.
Calcula o valor de hash dos dados especificados e o assina.
Sobrecargas
SignData(Byte[], Object) |
Calcula o valor de hash da matriz de byte especificada usando o algoritmo de hash especificado e assina o valor de hash resultante. |
SignData(Stream, Object) |
Calcula o valor de hash do fluxo de entrada especificado usando o algoritmo de hash especificado e assina o valor de hash resultante. |
SignData(Byte[], Int32, Int32, Object) |
Calcula o valor de hash de um subconjunto da matriz de byte especificada usando o algoritmo de hash especificado e assina o valor de hash resultante. |
SignData(Byte[], Object)
Calcula o valor de hash da matriz de byte especificada usando o algoritmo de hash especificado e assina o valor de hash resultante.
public:
cli::array <System::Byte> ^ SignData(cli::array <System::Byte> ^ buffer, System::Object ^ halg);
public byte[] SignData (byte[] buffer, object halg);
override this.SignData : byte[] * obj -> byte[]
member this.SignData : byte[] * obj -> byte[]
Public Function SignData (buffer As Byte(), halg As Object) As Byte()
Parâmetros
- buffer
- Byte[]
Os dados de entrada para hash e assinatura.
- halg
- Object
O algoritmo de hash a ser usado para criar o valor de hash.
Retornos
A assinatura RSA dos dados especificados.
Exceções
O parâmetro halg
é null
.
O parâmetro halg
não é um tipo válido.
Exemplos
O exemplo de código a seguir assina e verifica os dados.
using namespace System;
using namespace System::Security::Cryptography;
using namespace System::Text;
array<Byte>^ HashAndSignBytes( array<Byte>^DataToSign, RSAParameters Key )
{
try
{
// Create a new instance of RSACryptoServiceProvider using the
// key from RSAParameters.
RSACryptoServiceProvider^ RSAalg = gcnew RSACryptoServiceProvider;
RSAalg->ImportParameters( Key );
// Hash and sign the data. Pass a new instance of SHA256
// to specify the hashing algorithm.
return RSAalg->SignData( DataToSign, SHA256::Create() );
}
catch ( CryptographicException^ e )
{
Console::WriteLine( e->Message );
return nullptr;
}
}
bool VerifySignedHash( array<Byte>^DataToVerify, array<Byte>^SignedData, RSAParameters Key )
{
try
{
// Create a new instance of RSACryptoServiceProvider using the
// key from RSAParameters.
RSACryptoServiceProvider^ RSAalg = gcnew RSACryptoServiceProvider;
RSAalg->ImportParameters( Key );
// Verify the data using the signature. Pass a new instance of SHA256
// to specify the hashing algorithm.
return RSAalg->VerifyData( DataToVerify, SHA256::Create(), SignedData );
}
catch ( CryptographicException^ e )
{
Console::WriteLine( e->Message );
return false;
}
}
int main()
{
try
{
// Create a UnicodeEncoder to convert between byte array and string.
ASCIIEncoding^ ByteConverter = gcnew ASCIIEncoding;
String^ dataString = "Data to Sign";
// Create byte arrays to hold original, encrypted, and decrypted data.
array<Byte>^originalData = ByteConverter->GetBytes( dataString );
array<Byte>^signedData;
// Create a new instance of the RSACryptoServiceProvider class
// and automatically create a new key-pair.
RSACryptoServiceProvider^ RSAalg = gcnew 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.
signedData = HashAndSignBytes( originalData, Key );
// Verify the data and display the result to the
// console.
if ( VerifySignedHash( originalData, signedData, Key ) )
{
Console::WriteLine( "The data was verified." );
}
else
{
Console::WriteLine( "The data does not match the signature." );
}
}
catch ( ArgumentNullException^ )
{
Console::WriteLine( "The data was not signed or verified" );
}
}
using System;
using System.Security.Cryptography;
using System.Text;
class RSACSPSample
{
static void Main()
{
try
{
// Create a UnicodeEncoder to convert between byte array and string.
ASCIIEncoding ByteConverter = new ASCIIEncoding();
string dataString = "Data to Sign";
// Create byte arrays to hold original, encrypted, and decrypted data.
byte[] originalData = ByteConverter.GetBytes(dataString);
byte[] signedData;
// 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.
signedData = HashAndSignBytes(originalData, Key);
// Verify the data and display the result to the
// console.
if(VerifySignedHash(originalData, signedData, Key))
{
Console.WriteLine("The data was verified.");
}
else
{
Console.WriteLine("The data does not match the signature.");
}
}
catch(ArgumentNullException)
{
Console.WriteLine("The data was not signed or verified");
}
}
public static byte[] HashAndSignBytes(byte[] DataToSign, RSAParameters Key)
{
try
{
// 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 SHA256
// to specify the hashing algorithm.
return RSAalg.SignData(DataToSign, SHA256.Create());
}
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 SHA256
// to specify the hashing algorithm.
return RSAalg.VerifyData(DataToVerify, SHA256.Create(), SignedData);
}
catch(CryptographicException e)
{
Console.WriteLine(e.Message);
return false;
}
}
}
Imports System.Security.Cryptography
Imports System.Text
Module RSACSPExample
Sub Main()
Try
' Create a UnicodeEncoder to convert between byte array and string.
Dim ByteConverter As New ASCIIEncoding
Dim dataString As String = "Data to Sign"
' Create byte arrays to hold original, encrypted, and decrypted data.
Dim originalData As Byte() = ByteConverter.GetBytes(dataString)
Dim signedData() As Byte
' 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.
signedData = HashAndSignBytes(originalData, Key)
' Verify the data and display the result to the
' console.
If VerifySignedHash(originalData, signedData, Key) Then
Console.WriteLine("The data was verified.")
Else
Console.WriteLine("The data does not match the signature.")
End If
Catch e As ArgumentNullException
Console.WriteLine("The data was not signed or verified.")
End Try
End Sub
Function HashAndSignBytes(ByVal DataToSign() As Byte, ByVal Key As RSAParameters) As Byte()
Try
' 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 SHA256
' to specify the hashing algorithm.
Return RSAalg.SignData(DataToSign, SHA256.Create())
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 SHA256
' to specify the hashing algorithm.
Return RSAalg.VerifyData(DataToVerify, SHA256.Create(), SignedData)
Catch e As CryptographicException
Console.WriteLine(e.Message)
Return False
End Try
End Function
End Module
Comentários
Esse método cria uma assinatura digital que é verificada usando o VerifyData método .
O halg
parâmetro pode aceitar um String, um HashAlgorithmou um Type.
Confira também
Aplica-se a
SignData(Stream, Object)
Calcula o valor de hash do fluxo de entrada especificado usando o algoritmo de hash especificado e assina o valor de hash resultante.
public:
cli::array <System::Byte> ^ SignData(System::IO::Stream ^ inputStream, System::Object ^ halg);
public byte[] SignData (System.IO.Stream inputStream, object halg);
override this.SignData : System.IO.Stream * obj -> byte[]
member this.SignData : System.IO.Stream * obj -> byte[]
Public Function SignData (inputStream As Stream, halg As Object) As Byte()
Parâmetros
- inputStream
- Stream
O fluxo de entrada para hash e assinatura.
- halg
- Object
O algoritmo de hash a ser usado para criar o valor de hash.
Retornos
A assinatura RSA dos dados especificados.
Exceções
O parâmetro halg
é null
.
O parâmetro halg
não é um tipo válido.
Exemplos
O exemplo de código a seguir assina e verifica os dados.
using namespace System;
using namespace System::Security::Cryptography;
using namespace System::Text;
using namespace System::IO;
array<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 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 = gcnew RSACryptoServiceProvider;
RSAalg->ImportParameters( Key );
// Hash and sign the data. Pass a new instance of SHA256
// to specify the hashing algorithm.
return RSAalg->SignData( DataStream, SHA256::Create() );
}
catch ( CryptographicException^ e )
{
Console::WriteLine( e->Message );
return nullptr;
}
}
bool VerifySignedHash( array<Byte>^DataToVerify, array<Byte>^SignedData, RSAParameters Key )
{
try
{
// Create a new instance of RSACryptoServiceProvider using the
// key from RSAParameters.
RSACryptoServiceProvider^ RSAalg = gcnew RSACryptoServiceProvider;
RSAalg->ImportParameters( Key );
// Verify the data using the signature. Pass a new instance of SHA256
// to specify the hashing algorithm.
return RSAalg->VerifyData( DataToVerify, SHA256(), SignedData );
}
catch ( CryptographicException^ e )
{
Console::WriteLine( e->Message );
return false;
}
}
int main()
{
try
{
ASCIIEncoding^ ByteConverter = gcnew ASCIIEncoding;
// Create some bytes to be signed.
array<Byte>^dataBytes = ByteConverter->GetBytes( "Here is some data to sign!" );
// Create a buffer for the memory stream.
array<Byte>^buffer = gcnew array<Byte>(dataBytes->Length);
// Create a MemoryStream.
MemoryStream^ mStream = gcnew 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 = gcnew 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.
array<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" );
}
}
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 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 SHA256
// to specify the hashing algorithm.
return RSAalg.SignData(DataStream, SHA256.Create());
}
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 SHA256
// to specify the hashing algorithm.
return RSAalg.VerifyData(DataToVerify, SHA256.Create(), SignedData);
}
catch(CryptographicException e)
{
Console.WriteLine(e.Message);
return false;
}
}
}
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 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 SHA256
' to specify the hashing algorithm.
Return RSAalg.SignData(DataStream, SHA256.Create())
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 SHA256
' to specify the hashing algorithm.
Return RSAalg.VerifyData(DataToVerify, SHA256.Create(), SignedData)
Catch e As CryptographicException
Console.WriteLine(e.Message)
Return False
End Try
End Function
End Module
Comentários
O halg
parâmetro pode aceitar um String, um HashAlgorithmou um Type.
Confira também
Aplica-se a
SignData(Byte[], Int32, Int32, Object)
Calcula o valor de hash de um subconjunto da matriz de byte especificada usando o algoritmo de hash especificado e assina o valor de hash resultante.
public:
cli::array <System::Byte> ^ SignData(cli::array <System::Byte> ^ buffer, int offset, int count, System::Object ^ halg);
public byte[] SignData (byte[] buffer, int offset, int count, object halg);
override this.SignData : byte[] * int * int * obj -> byte[]
member this.SignData : byte[] * int * int * obj -> byte[]
Public Function SignData (buffer As Byte(), offset As Integer, count As Integer, halg As Object) As Byte()
Parâmetros
- buffer
- Byte[]
Os dados de entrada para hash e assinatura.
- offset
- Int32
O deslocamento na matriz do qual os dados começam a ser usados.
- count
- Int32
O número de bytes na matriz a ser usado como dados.
- halg
- Object
O algoritmo de hash a ser usado para criar o valor de hash.
Retornos
A assinatura RSA dos dados especificados.
Exceções
O parâmetro halg
é null
.
O parâmetro halg
não é um tipo válido.
Exemplos
O exemplo de código a seguir assina e verifica os dados.
using namespace System;
using namespace System::Security::Cryptography;
using namespace System::Text;
array<Byte>^ HashAndSignBytes( array<Byte>^DataToSign, RSAParameters Key, int Index, int Length )
{
try
{
// Create a new instance of RSACryptoServiceProvider using the
// key from RSAParameters.
RSACryptoServiceProvider^ RSAalg = gcnew RSACryptoServiceProvider;
RSAalg->ImportParameters( Key );
// Hash and sign the data. Pass a new instance of SHA256
// to specify the hashing algorithm.
return RSAalg->SignData( DataToSign, Index, Length, SHA256::Create() );
}
catch ( CryptographicException^ e )
{
Console::WriteLine( e->Message );
return nullptr;
}
}
bool VerifySignedHash( array<Byte>^DataToVerify, array<Byte>^SignedData, RSAParameters Key )
{
try
{
// Create a new instance of RSACryptoServiceProvider using the
// key from RSAParameters.
RSACryptoServiceProvider^ RSAalg = gcnew RSACryptoServiceProvider;
RSAalg->ImportParameters( Key );
// Verify the data using the signature. Pass a new instance of SHA256
// to specify the hashing algorithm.
return RSAalg->VerifyData( DataToVerify, SHA256::Create(), SignedData );
}
catch ( CryptographicException^ e )
{
Console::WriteLine( e->Message );
return false;
}
}
int main()
{
try
{
// Create a UnicodeEncoder to convert between byte array and string.
ASCIIEncoding^ ByteConverter = gcnew ASCIIEncoding;
String^ dataString = "Data to Sign";
// Create byte arrays to hold original, encrypted, and decrypted data.
array<Byte>^originalData = ByteConverter->GetBytes( dataString );
array<Byte>^signedData;
array<Byte>^smallArray;
// Create a new instance of the RSACryptoServiceProvider class
// and automatically create a new key-pair.
RSACryptoServiceProvider^ RSAalg = gcnew 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. Start at the fifth offset
// only use data from the next 7 bytes.
signedData = HashAndSignBytes( originalData, Key, 5, 7 );
// The previous method only signed one segment
// of the array. Create a new array for verification
// that only holds the data that was actually signed.
//
// Initialize the array.
smallArray = gcnew array<Byte>(7);
// Copy 7 bytes starting at the 5th index to
// the new array.
Array::Copy( originalData, 5, smallArray, 0, 7 );
// Verify the data and display the result to the
// console.
if ( VerifySignedHash( smallArray, signedData, Key ) )
{
Console::WriteLine( "The data was verified." );
}
else
{
Console::WriteLine( "The data does not match the signature." );
}
}
catch ( ArgumentNullException^ )
{
Console::WriteLine( "The data was not signed or verified" );
}
}
using System;
using System.Security.Cryptography;
using System.Text;
class RSACSPSample
{
static void Main()
{
try
{
// Create a UnicodeEncoder to convert between byte array and string.
ASCIIEncoding ByteConverter = new ASCIIEncoding();
string dataString = "Data to Sign";
// Create byte arrays to hold original, encrypted, and decrypted data.
byte[] originalData = ByteConverter.GetBytes(dataString);
byte[] signedData;
byte[] smallArray;
// 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. Start at the fifth offset
// only use data from the next 7 bytes.
signedData = HashAndSignBytes(originalData, Key, 5, 7 );
// The previous method only signed one segment
// of the array. Create a new array for verification
// that only holds the data that was actually signed.
//
// Initialize the array.
smallArray = new byte[7];
// Copy 7 bytes starting at the 5th index to
// the new array.
Array.Copy(originalData, 5 , smallArray, 0, 7);
// Verify the data and display the result to the
// console.
if(VerifySignedHash(smallArray, signedData, Key))
{
Console.WriteLine("The data was verified.");
}
else
{
Console.WriteLine("The data does not match the signature.");
}
}
catch(ArgumentNullException)
{
Console.WriteLine("The data was not signed or verified");
}
}
public static byte[] HashAndSignBytes(byte[] DataToSign, RSAParameters Key, int Index, int Length)
{
try
{
// 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 SHA256
// to specify the hashing algorithm.
return RSAalg.SignData(DataToSign,Index,Length, SHA256.Create());
}
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 SHA256
// to specify the hashing algorithm.
return RSAalg.VerifyData(DataToVerify, SHA256.Create(), SignedData);
}
catch(CryptographicException e)
{
Console.WriteLine(e.Message);
return false;
}
}
}
Imports System.Security.Cryptography
Imports System.Text
Module RSACSPExample
Sub Main()
Try
' Create a UnicodeEncoder to convert between byte array and string.
Dim ByteConverter As New ASCIIEncoding
Dim dataString As String = "Data to Sign"
' Create byte arrays to hold original, encrypted, and decrypted data.
Dim originalData As Byte() = ByteConverter.GetBytes(dataString)
Dim signedData() As Byte
Dim smallArray() As Byte
' 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. Start at the fifth offset
' only use data from the next 7 bytes.
signedData = HashAndSignBytes(originalData, Key, 5, 7)
' The previous function only signed one segment
' of the array. Create a new array for verification
' that only holds the data that was actually signed.
'
' Initialize the array.
smallArray = New Byte(6) {}
' Copy 7 bytes starting at the 5th index to
' the new array.
Array.Copy(originalData, 5, smallArray, 0, 7)
' Verify the data and display the result to the
' console.
If VerifySignedHash(smallArray, signedData, Key) Then
Console.WriteLine("The data was verified.")
Else
Console.WriteLine("The data does not match the signature.")
End If
Catch e As ArgumentNullException
Console.WriteLine("The data was not signed or verified")
End Try
End Sub
Function HashAndSignBytes(ByVal DataToSign() As Byte, ByVal Key As RSAParameters, ByVal Index As Integer, ByVal Length As Integer) As Byte()
Try
' 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 SHA256
' to specify the hashing algorithm.
Return RSAalg.SignData(DataToSign, Index, Length, SHA256.Create())
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 SHA256
' to specify the hashing algorithm.
Return RSAalg.VerifyData(DataToVerify, SHA256.Create(), SignedData)
Catch e As CryptographicException
Console.WriteLine(e.Message)
Return False
End Try
End Function
End Module
Comentários
Esse método cria uma assinatura digital que é verificada usando o VerifyData método .
O halg
parâmetro pode aceitar um String, um HashAlgorithmou um Type. O valor da cadeia de caracteres pode ser um dos seguintes:
O nome amigável do OID (identificador de objeto) do algoritmo de hash a ser usado, um nome registrado no arquivo de configuração de criptografia ou um na tabela OID da API de Criptografia.
O valor OID. O OID deve ser reconhecido pela API de Criptografia.
Por exemplo, você pode usar SignData(new byte[5], "1.3.14.3.2.26") ou SignData(new byte[5], "sha1" ou SignData(new byte[5], "SHA1").