RSACryptoServiceProvider.Encrypt Method
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Encrypts data with the RSA algorithm.
| Encrypt(Byte[], Boolean) |
Encrypts data with the RSA algorithm. |
| Encrypt(Byte[], RSAEncryptionPadding) |
Encrypts data with the RSA algorithm using the specified padding. |
Encrypts data with the RSA algorithm.
public:
cli::array <System::Byte> ^ Encrypt(cli::array <System::Byte> ^ rgb, bool fOAEP);public byte[] Encrypt(byte[] rgb, bool fOAEP);override this.Encrypt : byte[] * bool -> byte[]member this.Encrypt : byte[] * bool -> byte[]Public Function Encrypt (rgb As Byte(), fOAEP As Boolean) As Byte()Parameters
- rgb
- Byte[]
The data to be encrypted.
- fOAEP
- Boolean
true to perform direct RSA encryption using OAEP padding (only available on a computer running Windows XP or later); otherwise, false to use PKCS#1 v1.5 padding.
Returns
The encrypted data.
Exceptions
The cryptographic service provider (CSP) cannot be acquired.
-or-
The length of the rgb parameter is greater than the maximum allowed length.
rgb is null.
Examples
The following code example initializes an RSACryptoServiceProvider object to the value of a public key (sent by another party), generates a session key using the Aes algorithm, and then encrypts the session key using the RSACryptoServiceProvider object. Using this scheme, the session key could be sent back to the owner of the private RSA key and the two parties could use the session key to exchange encrypted data.
#using <System.dll>
using namespace System;
using namespace System::Security::Cryptography;
int main()
{
try
{
//initialze the Byte arrays to the public key information.
array<Byte>^PublicKey = {214,46,220,83,160,73,40,39,201,155,19,202,3,11,191,178,56,74,90,36,248,103,18,144,170,163,145,87,54,61,34,220,222,207,137,149,173,14,92,120,206,222,158,28,40,24,30,16,175,108,128,35,230,118,40,121,113,125,216,130,11,24,90,48,194,240,105,44,76,34,57,249,228,125,80,38,9,136,29,117,207,139,168,181,85,137,126,10,126,242,120,247,121,8,100,12,201,171,38,226,193,180,190,117,177,87,143,242,213,11,44,180,113,93,106,99,179,68,175,211,164,116,64,148,226,254,172,147};
array<Byte>^Exponent = {1,0,1};
//Values to store encrypted symmetric keys.
array<Byte>^EncryptedSymmetricKey;
array<Byte>^EncryptedSymmetricIV;
//Create a new instance of RSACryptoServiceProvider.
RSACryptoServiceProvider^ RSA = gcnew RSACryptoServiceProvider;
//Create a new instance of RSAParameters.
RSAParameters RSAKeyInfo;
//Set RSAKeyInfo to the public key values.
RSAKeyInfo.Modulus = PublicKey;
RSAKeyInfo.Exponent = Exponent;
//Import key parameters into RSA.
RSA->ImportParameters( RSAKeyInfo );
//Create a new instance of the Aes class.
Aes^ aes = Aes::Create();
//Encrypt the symmetric key and IV.
EncryptedSymmetricKey = RSA->Encrypt( aes->Key, false );
EncryptedSymmetricIV = RSA->Encrypt( aes->IV, false );
Console::WriteLine( "Aes Key and IV have been encrypted with RSACryptoServiceProvider." );
}
catch ( CryptographicException^ e )
{
//Catch and display a CryptographicException
//to the console.
Console::WriteLine( e->Message );
}
}
using System;
using System.Security.Cryptography;
class RSACSPSample
{
static void Main()
{
try
{ //initialze the byte arrays to the public key information.
byte[] PublicKey = {214,46,220,83,160,73,40,39,201,155,19,202,3,11,191,178,56,
74,90,36,248,103,18,144,170,163,145,87,54,61,34,220,222,
207,137,149,173,14,92,120,206,222,158,28,40,24,30,16,175,
108,128,35,230,118,40,121,113,125,216,130,11,24,90,48,194,
240,105,44,76,34,57,249,228,125,80,38,9,136,29,117,207,139,
168,181,85,137,126,10,126,242,120,247,121,8,100,12,201,171,
38,226,193,180,190,117,177,87,143,242,213,11,44,180,113,93,
106,99,179,68,175,211,164,116,64,148,226,254,172,147};
byte[] Exponent = {1,0,1};
//Values to store encrypted symmetric keys.
byte[] EncryptedSymmetricKey;
byte[] EncryptedSymmetricIV;
//Create a new instance of RSACryptoServiceProvider.
RSACryptoServiceProvider RSA = new RSACryptoServiceProvider();
//Create a new instance of RSAParameters.
RSAParameters RSAKeyInfo = new RSAParameters();
//Set RSAKeyInfo to the public key values.
RSAKeyInfo.Modulus = PublicKey;
RSAKeyInfo.Exponent = Exponent;
//Import key parameters into RSA.
RSA.ImportParameters(RSAKeyInfo);
//Create a new instance of the Aes class.
Aes aes = Aes.Create();
//Encrypt the symmetric key and IV.
EncryptedSymmetricKey = RSA.Encrypt(aes.Key, false);
EncryptedSymmetricIV = RSA.Encrypt(aes.IV, false);
Console.WriteLine("Aes Key and IV have been encrypted with RSACryptoServiceProvider.");
}
//Catch and display a CryptographicException
//to the console.
catch(CryptographicException e)
{
Console.WriteLine(e.Message);
}
}
}
Imports System.Security.Cryptography
Class RSACSPSample
Shared Sub Main()
Try
'initialze the byte arrays to the public key information.
Dim PublicKey As Byte() = {214, 46, 220, 83, 160, 73, 40, 39, 201, 155, 19, 202, 3, 11, 191, 178, 56, 74, 90, 36, 248, 103, 18, 144, 170, 163, 145, 87, 54, 61, 34, 220, 222, 207, 137, 149, 173, 14, 92, 120, 206, 222, 158, 28, 40, 24, 30, 16, 175, 108, 128, 35, 230, 118, 40, 121, 113, 125, 216, 130, 11, 24, 90, 48, 194, 240, 105, 44, 76, 34, 57, 249, 228, 125, 80, 38, 9, 136, 29, 117, 207, 139, 168, 181, 85, 137, 126, 10, 126, 242, 120, 247, 121, 8, 100, 12, 201, 171, 38, 226, 193, 180, 190, 117, 177, 87, 143, 242, 213, 11, 44, 180, 113, 93, 106, 99, 179, 68, 175, 211, 164, 116, 64, 148, 226, 254, 172, 147}
Dim Exponent As Byte() = {1, 0, 1}
'Values to store encrypted symmetric keys.
Dim EncryptedSymmetricKey() As Byte
Dim EncryptedSymmetricIV() As Byte
'Create a new instance of RSACryptoServiceProvider.
Dim RSA As New RSACryptoServiceProvider()
'Create a new instance of RSAParameters.
Dim RSAKeyInfo As New RSAParameters()
'Set RSAKeyInfo to the public key values.
RSAKeyInfo.Modulus = PublicKey
RSAKeyInfo.Exponent = Exponent
'Import key parameters into RSA.
RSA.ImportParameters(RSAKeyInfo)
'Create a new instance of the Aes class.
Dim aes As Aes = Aes.Create()
'Encrypt the symmetric key and IV.
EncryptedSymmetricKey = RSA.Encrypt(aes.Key, False)
EncryptedSymmetricIV = RSA.Encrypt(aes.IV, False)
Console.WriteLine("Aes Key and IV have been encrypted with RSA.")
'Catch and display a CryptographicException
'to the console.
Catch e As CryptographicException
Console.WriteLine(e.Message)
End Try
End Sub
End Class
Remarks
The following table describes the padding supported by different versions of Microsoft Windows and the maximum length of rgb allowed by the different combinations of operating systems and padding.
| Padding | Maximum Length of rgb Parameter |
|---|---|
| OAEP padding (PKCS#1 v2) | Modulus size -2 -2*hLen, where hLen is the size of the hash. |
| Direct Encryption (PKCS#1 v1.5) | Modulus size - 11. (11 bytes is the minimum padding possible.) |
Use Decrypt to decrypt the results of this method.
See also
Applies to
.NET 10 and other versions
| Product | Versions |
|---|---|
| .NET | Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9, 10 |
| .NET Framework | 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1 |
| .NET Standard | 2.0, 2.1 |
Encrypts data with the RSA algorithm using the specified padding.
public:
override cli::array <System::Byte> ^ Encrypt(cli::array <System::Byte> ^ data, System::Security::Cryptography::RSAEncryptionPadding ^ padding);public override byte[] Encrypt(byte[] data, System.Security.Cryptography.RSAEncryptionPadding padding);override this.Encrypt : byte[] * System.Security.Cryptography.RSAEncryptionPadding -> byte[]Public Overrides Function Encrypt (data As Byte(), padding As RSAEncryptionPadding) As Byte()Parameters
- data
- Byte[]
The data to encrypt.
- padding
- RSAEncryptionPadding
The padding.
Returns
The encrypted data.
Exceptions
The padding mode is not supported.
Remarks
padding must be either RSAEncryptionPadding.Pkcs1 or RSAEncryptionPadding.OaepSHA1.
Applies to
.NET 10 and other versions
| Product | Versions |
|---|---|
| .NET | Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9, 10 |
| .NET Framework | 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1 |
| .NET Standard | 2.0, 2.1 |
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