RSACryptoServiceProvider.SignHash Método
Definição
Importante
Algumas informações dizem respeito a um produto pré-lançado que pode ser substancialmente modificado antes de ser lançado. A Microsoft não faz garantias, de forma expressa ou implícita, em relação à informação aqui apresentada.
Calcula a assinatura para o valor de hash especificado.
Sobrecargas
| Name | Description |
|---|---|
| SignHash(Byte[], String) |
Calcula a assinatura para o valor de hash especificado. |
| SignHash(Byte[], HashAlgorithmName, RSASignaturePadding) |
Calcula a assinatura para o valor de hash especificado usando o enchimento especificado. |
SignHash(Byte[], String)
Calcula a assinatura para o valor de hash especificado.
public:
cli::array <System::Byte> ^ SignHash(cli::array <System::Byte> ^ rgbHash, System::String ^ str);
public byte[] SignHash(byte[] rgbHash, string? str);
public byte[] SignHash(byte[] rgbHash, string str);
override this.SignHash : byte[] * string -> byte[]
member this.SignHash : byte[] * string -> byte[]
Public Function SignHash (rgbHash As Byte(), str As String) As Byte()
Parâmetros
- rgbHash
- Byte[]
O valor de hash dos dados a assinar.
- str
- String
O identificador do algoritmo de hash (OID) é usado para criar o valor de hash dos dados.
Devoluções
A RSA assinatura para o valor de hash especificado.
Exceções
O rgbHash parâmetro é null.
O fornecedor de serviços criptográficos (CSP) não pode ser adquirido.
-ou-
Não há chave privada.
Exemplos
O exemplo de código seguinte encripta alguns dados, cria um hash dos dados encriptados e depois assina o hash com uma assinatura digital.
// This example uses the SHA1 algorithm.
// Due to collision problems with SHA1, Microsoft recommends SHA256 or better.
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);
bool dataOK = rsaCSP.VerifyData(signedData, CryptoConfig.MapNameToOID("SHA1"), signature);
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);
}
}
}
' This example uses the SHA1 algorithm.
' Due to collision problems with SHA1, Microsoft recommends SHA256 or better.
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
End Class
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
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
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
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
Dim dataOK As Boolean
rsaCSP.ImportParameters(rsaParams)
dataOK = rsaCSP.VerifyData(signedData, CryptoConfig.MapNameToOID("SHA1"), signature)
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
End Class
End Namespace 'RSACryptoServiceProvider_Examples
Observações
Este método cria uma assinatura digital que é verificada através do método VerifyHash .
Os algoritmos de hash válidos são SHA1 e MD5. O identificador do algoritmo pode ser derivado do nome do hash usando o MapNameToOID método.
Devido a problemas de colisão com SHA-1 e MD5, a Microsoft recomenda um modelo de segurança baseado no SHA-256 ou superior.
Ver também
Aplica-se a
SignHash(Byte[], HashAlgorithmName, RSASignaturePadding)
Calcula a assinatura para o valor de hash especificado usando o enchimento especificado.
public:
override cli::array <System::Byte> ^ SignHash(cli::array <System::Byte> ^ hash, System::Security::Cryptography::HashAlgorithmName hashAlgorithm, System::Security::Cryptography::RSASignaturePadding ^ padding);
public override byte[] SignHash(byte[] hash, System.Security.Cryptography.HashAlgorithmName hashAlgorithm, System.Security.Cryptography.RSASignaturePadding padding);
override this.SignHash : byte[] * System.Security.Cryptography.HashAlgorithmName * System.Security.Cryptography.RSASignaturePadding -> byte[]
Public Overrides Function SignHash (hash As Byte(), hashAlgorithm As HashAlgorithmName, padding As RSASignaturePadding) As Byte()
Parâmetros
- hash
- Byte[]
O valor de hash dos dados a assinar.
- hashAlgorithm
- HashAlgorithmName
O nome do algoritmo de hash é usado para criar o valor de hash dos dados.
- padding
- RSASignaturePadding
O preenchimento.
Devoluções
A RSA assinatura para o valor de hash especificado.
Exceções
hashAlgorithm é null ou Empty.
padding não é igual Pkcs1a .