TripleDES.Create メソッド
定義
重要
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TripleDES アルゴリズムを実行するための暗号オブジェクトのインスタンスを作成します。
オーバーロード
Create() |
TripleDES アルゴリズムを実行するための暗号オブジェクトのインスタンスを作成します。 |
Create(String) |
TripleDES アルゴリズムの指定した実装を実行する暗号オブジェクトのインスタンスを作成します。 |
Create()
TripleDES アルゴリズムを実行するための暗号オブジェクトのインスタンスを作成します。
public:
static System::Security::Cryptography::TripleDES ^ Create();
public static System.Security.Cryptography.TripleDES Create ();
[System.Runtime.Versioning.UnsupportedOSPlatform("browser")]
public static System.Security.Cryptography.TripleDES Create ();
static member Create : unit -> System.Security.Cryptography.TripleDES
[<System.Runtime.Versioning.UnsupportedOSPlatform("browser")>]
static member Create : unit -> System.Security.Cryptography.TripleDES
Public Shared Function Create () As TripleDES
戻り値
暗号オブジェクトのインスタンス。
- 属性
例
次のコード例は、オブジェクトを作成して使用して、ファイル内の TripleDES データを暗号化および暗号化解除する方法を示しています。
using namespace System;
using namespace System::IO;
using namespace System::Security::Cryptography;
using namespace System::Text;
void EncryptTextToFile(String^ text, String^ path, array<Byte>^ key, array<Byte>^ iv);
String^ DecryptTextFromFile(String^ path, array<Byte>^ key, array<Byte>^ iv);
int main()
{
try
{
array<Byte>^ key;
array<Byte>^ iv;
// Create a new TripleDES object to generate a random key
// and initialization vector (IV).
{
TripleDES^ tripleDes;
try
{
tripleDes = TripleDES::Create();
key = tripleDes->Key;
iv = tripleDes->IV;
}
finally
{
delete tripleDes;
}
}
// Create a string to encrypt.
String^ original = "Here is some data to encrypt.";
// The name/path of the file to write.
String^ filename = "CText.enc";
// Encrypt the string to a file.
EncryptTextToFile(original, filename, key, iv);
// Decrypt the file back to a string.
String^ decrypted = DecryptTextFromFile(filename, key, iv);
// Display the decrypted string to the console.
Console::WriteLine(decrypted);
}
catch (Exception^ e)
{
Console::WriteLine(e->Message);
}
}
void EncryptTextToFile(String^ text, String^ path, array<Byte>^ key, array<Byte>^ iv)
{
FileStream^ fStream = nullptr;
TripleDES^ tripleDes = nullptr;
ICryptoTransform^ encryptor = nullptr;
CryptoStream^ cStream = nullptr;
try
{
// Create or open the specified file.
fStream = File::Open(path, FileMode::Create);
// Create a new TripleDES object.
tripleDes = TripleDES::Create();
// Create a TripleDES encryptor from the key and IV
encryptor = tripleDes->CreateEncryptor(key, iv);
// Create a CryptoStream using the FileStream and encryptor
cStream = gcnew CryptoStream(fStream, encryptor, CryptoStreamMode::Write);
// Convert the provided string to a byte array.
array<Byte>^ toEncrypt = Encoding::UTF8->GetBytes(text);
// Write the byte array to the crypto stream.
cStream->Write(toEncrypt, 0, toEncrypt->Length);
}
catch (CryptographicException^ e)
{
Console::WriteLine("A Cryptographic error occurred: {0}", e->Message);
throw;
}
finally
{
if (cStream != nullptr)
delete cStream;
if (encryptor != nullptr)
delete encryptor;
if (tripleDes != nullptr)
delete tripleDes;
if (fStream != nullptr)
delete fStream;
}
}
String^ DecryptTextFromFile(String^ path, array<Byte>^ key, array<Byte>^ iv)
{
FileStream^ fStream = nullptr;
TripleDES^ tripleDes = nullptr;
ICryptoTransform^ decryptor = nullptr;
CryptoStream^ cStream = nullptr;
StreamReader^ reader = nullptr;
try
{
// Open the specified file
fStream = File::OpenRead(path);
// Create a new TripleDES object.
tripleDes = TripleDES::Create();
// Create a TripleDES decryptor from the key and IV
decryptor = tripleDes->CreateDecryptor(key, iv);
// Create a CryptoStream using the FileStream and decryptor
cStream = gcnew CryptoStream(fStream, decryptor, CryptoStreamMode::Read);
// Create a StreamReader to turn the bytes back into text
reader = gcnew StreamReader(cStream, Encoding::UTF8);
// Read back all of the text from the StreamReader, which receives
// the decrypted bytes from the CryptoStream, which receives the
// encrypted bytes from the FileStream.
return reader->ReadToEnd();
}
catch (CryptographicException^ e)
{
Console::WriteLine("A Cryptographic error occurred: {0}", e->Message);
throw;
}
finally
{
if (cStream != nullptr)
delete cStream;
if (decryptor != nullptr)
delete decryptor;
if (tripleDes != nullptr)
delete tripleDes;
if (fStream != nullptr)
delete fStream;
}
}
using System;
using System.IO;
using System.Security.Cryptography;
using System.Text;
class TripleDESSample
{
static void Main()
{
try
{
byte[] key;
byte[] iv;
// Create a new TripleDES object to generate a random key
// and initialization vector (IV).
using (TripleDES tripleDes = TripleDES.Create())
{
key = tripleDes.Key;
iv = tripleDes.IV;
}
// Create a string to encrypt.
string original = "Here is some data to encrypt.";
// The name/path of the file to write.
string filename = "CText.enc";
// Encrypt the string to a file.
EncryptTextToFile(original, filename, key, iv);
// Decrypt the file back to a string.
string decrypted = DecryptTextFromFile(filename, key, iv);
// Display the decrypted string to the console.
Console.WriteLine(decrypted);
}
catch (Exception e)
{
Console.WriteLine(e.Message);
}
}
public static void EncryptTextToFile(string text, string path, byte[] key, byte[] iv)
{
try
{
// Create or open the specified file.
using (FileStream fStream = File.Open(path, FileMode.Create))
// Create a new TripleDES object.
using (TripleDES tripleDes = TripleDES.Create())
// Create a TripleDES encryptor from the key and IV
using (ICryptoTransform encryptor = tripleDes.CreateEncryptor(key, iv))
// Create a CryptoStream using the FileStream and encryptor
using (var cStream = new CryptoStream(fStream, encryptor, CryptoStreamMode.Write))
{
// Convert the provided string to a byte array.
byte[] toEncrypt = Encoding.UTF8.GetBytes(text);
// Write the byte array to the crypto stream.
cStream.Write(toEncrypt, 0, toEncrypt.Length);
}
}
catch (CryptographicException e)
{
Console.WriteLine("A Cryptographic error occurred: {0}", e.Message);
throw;
}
}
public static string DecryptTextFromFile(string path, byte[] key, byte[] iv)
{
try
{
// Open the specified file
using (FileStream fStream = File.OpenRead(path))
// Create a new TripleDES object.
using (TripleDES tripleDes = TripleDES.Create())
// Create a TripleDES decryptor from the key and IV
using (ICryptoTransform decryptor = tripleDes.CreateDecryptor(key, iv))
// Create a CryptoStream using the FileStream and decryptor
using (var cStream = new CryptoStream(fStream, decryptor, CryptoStreamMode.Read))
// Create a StreamReader to turn the bytes back into text
using (StreamReader reader = new StreamReader(cStream, Encoding.UTF8))
{
// Read back all of the text from the StreamReader, which receives
// the decrypted bytes from the CryptoStream, which receives the
// encrypted bytes from the FileStream.
return reader.ReadToEnd();
}
}
catch (CryptographicException e)
{
Console.WriteLine("A Cryptographic error occurred: {0}", e.Message);
throw;
}
}
}
Imports System.IO
Imports System.Security.Cryptography
Imports System.Text
Module TripleDESSample
Sub Main()
Try
Dim key As Byte()
Dim iv As Byte()
' Create a new TripleDES object to generate a key
' and initialization vector (IV).
Using tripleDes As TripleDES = TripleDES.Create
key = tripleDes.Key
iv = tripleDes.IV
End Using
' Create a string to encrypt.
Dim original As String = "Here is some data to encrypt."
' The name/path of the file to write.
Dim filename As String = "CText.enc"
' Encrypt the string to a file.
EncryptTextToFile(original, filename, key, iv)
' Decrypt the file back to a string.
Dim decrypted As String = DecryptTextFromFile(filename, key, iv)
' Display the decrypted string to the console.
Console.WriteLine(decrypted)
Catch e As Exception
Console.WriteLine(e.Message)
End Try
End Sub
Sub EncryptTextToFile(text As String, path As String, key As Byte(), iv As Byte())
Try
' Create or open the specified file.
' Create a new TripleDES object,
' Create a TripleDES encryptor from the key and IV,
' Create a CryptoStream using the MemoryStream And encryptor
Using fStream As FileStream = File.Open(path, FileMode.Create),
tripleDes As TripleDES = TripleDES.Create,
encryptor As ICryptoTransform = tripleDes.CreateEncryptor(key, iv),
cStream = New CryptoStream(fStream, encryptor, CryptoStreamMode.Write)
' Convert the passed string to a byte array.
Dim toEncrypt As Byte() = Encoding.UTF8.GetBytes(text)
' Write the byte array to the crypto stream.
cStream.Write(toEncrypt, 0, toEncrypt.Length)
End Using
Catch e As CryptographicException
Console.WriteLine("A Cryptographic error occurred: {0}", e.Message)
Throw
End Try
End Sub
Function DecryptTextFromFile(path As String, key As Byte(), iv As Byte()) As String
Try
' Open the specified file
' Create a new TripleDES object.
' Create a TripleDES decryptor from the key and IV
' Create a CryptoStream using the MemoryStream and decryptor
' Create a StreamReader to turn the bytes back into text
Using mStream As FileStream = File.OpenRead(path),
tripleDes As TripleDES = TripleDES.Create,
decryptor As ICryptoTransform = tripleDes.CreateDecryptor(key, iv),
cStream = New CryptoStream(mStream, decryptor, CryptoStreamMode.Read),
reader = New StreamReader(cStream, Encoding.UTF8)
' Read back all of the text from the StreamReader, which receives
' the decrypted bytes from the CryptoStream, which receives the
' encrypted bytes from the FileStream.
Return reader.ReadToEnd()
End Using
Catch e As CryptographicException
Console.WriteLine("A Cryptographic error occurred: {0}", e.Message)
Return Nothing
End Try
End Function
End Module
次のコード例は、オブジェクトを作成して使用して、メモリ内の TripleDES データを暗号化および暗号化解除する方法を示しています。
using namespace System;
using namespace System::Security::Cryptography;
using namespace System::Text;
using namespace System::IO;
array<Byte>^ EncryptTextToMemory(String^ text, array<Byte>^ key, array<Byte>^ iv);
String^ DecryptTextFromMemory(array<Byte>^ encrypted, array<Byte>^ key, array<Byte>^ iv);
int main()
{
try
{
array<Byte>^ key;
array<Byte>^ iv;
// Create a new TripleDES object to generate a random key
// and initialization vector (IV).
{
TripleDES^ tripleDes;
try
{
tripleDes = TripleDES::Create();
key = tripleDes->Key;
iv = tripleDes->IV;
}
finally
{
delete tripleDes;
}
}
// Create a string to encrypt.
String^ original = "Here is some data to encrypt.";
// Encrypt the string to an in-memory buffer.
array<Byte>^ encrypted = EncryptTextToMemory(original, key, iv);
// Decrypt the buffer back to a string.
String^ decrypted = DecryptTextFromMemory(encrypted, key, iv);
// Display the decrypted string to the console.
Console::WriteLine(decrypted);
}
catch (Exception^ e)
{
Console::WriteLine(e->Message);
}
}
array<Byte>^ EncryptTextToMemory(String^ text, array<Byte>^ key, array<Byte>^ iv)
{
MemoryStream^ mStream = nullptr;
try
{
// Create a MemoryStream.
mStream = gcnew MemoryStream;
TripleDES^ tripleDes = nullptr;
ICryptoTransform^ encryptor = nullptr;
CryptoStream^ cStream = nullptr;
try
{
// Create a new TripleDES object.
tripleDes = TripleDES::Create();
// Create a TripleDES encryptor from the key and IV
encryptor = tripleDes->CreateEncryptor(key, iv);
// Create a CryptoStream using the MemoryStream and encryptor
cStream = gcnew CryptoStream(mStream, encryptor, CryptoStreamMode::Write);
// Convert the provided string to a byte array.
array<Byte>^ toEncrypt = Encoding::UTF8->GetBytes(text);
// Write the byte array to the crypto stream.
cStream->Write(toEncrypt, 0, toEncrypt->Length);
// Disposing the CryptoStream completes the encryption and flushes the stream.
delete cStream;
// Get an array of bytes from the MemoryStream that holds the encrypted data.
array<Byte>^ ret = mStream->ToArray();
// Return the encrypted buffer.
return ret;
}
finally
{
if (cStream != nullptr)
delete cStream;
if (encryptor != nullptr)
delete encryptor;
if (tripleDes != nullptr)
delete tripleDes;
}
}
catch (CryptographicException^ e)
{
Console::WriteLine("A Cryptographic error occurred: {0}", e->Message);
throw;
}
finally
{
if (mStream != nullptr)
delete mStream;
}
}
String^ DecryptTextFromMemory(array<Byte>^ encrypted, array<Byte>^ key, array<Byte>^ iv)
{
MemoryStream^ mStream = nullptr;
TripleDES^ tripleDes = nullptr;
ICryptoTransform^ decryptor = nullptr;
CryptoStream^ cStream = nullptr;
try
{
// Create buffer to hold the decrypted data.
// TripleDES-encrypted data will always be slightly bigger than the decrypted data.
array<Byte>^ decrypted = gcnew array<Byte>(encrypted->Length);
Int32 offset = 0;
// Create a new MemoryStream using the provided array of encrypted data.
mStream = gcnew MemoryStream(encrypted);
// Create a new TripleDES object.
tripleDes = TripleDES::Create();
// Create a TripleDES decryptor from the key and IV
decryptor = tripleDes->CreateDecryptor(key, iv);
// Create a CryptoStream using the MemoryStream and decryptor
cStream = gcnew CryptoStream(mStream, decryptor, CryptoStreamMode::Read);
// Keep reading from the CryptoStream until it finishes (returns 0).
Int32 read = 1;
while (read > 0)
{
read = cStream->Read(decrypted, offset, decrypted->Length - offset);
offset += read;
}
// Convert the buffer into a string and return it.
return Encoding::UTF8->GetString(decrypted, 0, offset);
}
catch (CryptographicException^ e)
{
Console::WriteLine("A Cryptographic error occurred: {0}", e->Message);
throw;
}
finally
{
if (cStream != nullptr)
delete cStream;
if (decryptor != nullptr)
delete decryptor;
if (tripleDes != nullptr)
delete tripleDes;
if (mStream != nullptr)
delete mStream;
}
}
Imports System.Security.Cryptography
Imports System.Text
Imports System.IO
Module TripleDESSample
Sub Main()
Try
Dim key As Byte()
Dim iv As Byte()
' Create a new TripleDES object to generate a key
' and initialization vector (IV).
Using tripleDes As TripleDES = TripleDES.Create
key = tripleDes.Key
iv = tripleDes.IV
End Using
' Create a string to encrypt.
Dim original As String = "Here is some data to encrypt."
' Encrypt the string to an in-memory buffer.
Dim encrypted As Byte() = EncryptTextToMemory(original, key, iv)
' Decrypt the buffer back to a string.
Dim decrypted As String = DecryptTextFromMemory(encrypted, key, iv)
' Display the decrypted string to the console.
Console.WriteLine(decrypted)
Catch e As Exception
Console.WriteLine(e.Message)
End Try
End Sub
Function EncryptTextToMemory(text As String, key As Byte(), iv As Byte()) As Byte()
Try
' Create a MemoryStream.
Using mStream As New MemoryStream
' Create a new TripleDES object,
' Create a TripleDES encryptor from the key and IV,
' Create a CryptoStream using the MemoryStream And encryptor
Using tripleDes As TripleDES = TripleDES.Create,
encryptor As ICryptoTransform = tripleDes.CreateEncryptor(key, iv),
cStream = New CryptoStream(mStream, encryptor, CryptoStreamMode.Write)
' Convert the passed string to a byte array.
Dim toEncrypt As Byte() = Encoding.UTF8.GetBytes(text)
' Write the byte array to the crypto stream and flush it.
cStream.Write(toEncrypt, 0, toEncrypt.Length)
' Ending the using block for the CryptoStream completes the encryption.
End Using
' Get an array of bytes from the MemoryStream that holds the encrypted data.
Dim ret As Byte() = mStream.ToArray()
' Return the encrypted buffer.
Return ret
End Using
Catch e As CryptographicException
Console.WriteLine("A Cryptographic error occurred: {0}", e.Message)
Throw
End Try
End Function
Function DecryptTextFromMemory(encrypted As Byte(), key As Byte(), iv As Byte()) As String
Try
' Create a buffer to hold the decrypted data.
' TripleDES-encrypted data will always be slightly bigger than the decrypted data.
Dim decrypted(encrypted.Length - 1) As Byte
Dim offset As Integer = 0
' Create a new MemoryStream using the provided array of encrypted data.
' Create a new TripleDES object.
' Create a TripleDES decryptor from the key and IV
' Create a CryptoStream using the MemoryStream and decryptor
Using mStream As New MemoryStream(encrypted),
tripleDes As TripleDES = TripleDES.Create,
decryptor As ICryptoTransform = tripleDes.CreateDecryptor(key, iv),
cStream = New CryptoStream(mStream, decryptor, CryptoStreamMode.Read)
' Keep reading from the CryptoStream until it finishes (returns 0).
Dim read As Integer = 1
While (read > 0)
read = cStream.Read(decrypted, offset, decrypted.Length - offset)
offset += read
End While
End Using
' Convert the buffer into a string and return it.
Return New ASCIIEncoding().GetString(decrypted, 0, offset)
Catch e As CryptographicException
Console.WriteLine("A Cryptographic error occurred: {0}", e.Message)
Return Nothing
End Try
End Function
End Module
注釈
TripleDES クラスの新しいインスタンスを作成します。
こちらもご覧ください
適用対象
Create(String)
TripleDES アルゴリズムの指定した実装を実行する暗号オブジェクトのインスタンスを作成します。
public:
static System::Security::Cryptography::TripleDES ^ Create(System::String ^ str);
public static System.Security.Cryptography.TripleDES? Create (string str);
public static System.Security.Cryptography.TripleDES Create (string str);
static member Create : string -> System.Security.Cryptography.TripleDES
Public Shared Function Create (str As String) As TripleDES
パラメーター
戻り値
暗号オブジェクトのインスタンス。
例
次のコード例は、オブジェクトを作成して使用して、ファイル内の TripleDES データを暗号化および暗号化解除する方法を示しています。
using namespace System;
using namespace System::Security::Cryptography;
using namespace System::Text;
using namespace System::IO;
void EncryptTextToFile( String^ Data, String^ FileName, array<Byte>^Key, array<Byte>^IV )
{
try
{
// Create or open the specified file.
FileStream^ fStream = File::Open( FileName, FileMode::OpenOrCreate );
// Create a new TripleDES object.
TripleDES^ tripleDESalg = TripleDES::Create();
// Create a CryptoStream using the FileStream
// and the passed key and initialization vector (IV).
CryptoStream^ cStream = gcnew CryptoStream( fStream,tripleDESalg->CreateEncryptor( Key, IV ),CryptoStreamMode::Write );
// Create a StreamWriter using the CryptoStream.
StreamWriter^ sWriter = gcnew StreamWriter( cStream );
// Write the data to the stream
// to encrypt it.
sWriter->WriteLine( Data );
// Close the streams and
// close the file.
sWriter->Close();
cStream->Close();
fStream->Close();
}
catch ( CryptographicException^ e )
{
Console::WriteLine( "A Cryptographic error occurred: {0}", e->Message );
}
catch ( UnauthorizedAccessException^ e )
{
Console::WriteLine( "A file error occurred: {0}", e->Message );
}
}
String^ DecryptTextFromFile( String^ FileName, array<Byte>^Key, array<Byte>^IV )
{
try
{
// Create or open the specified file.
FileStream^ fStream = File::Open( FileName, FileMode::OpenOrCreate );
// Create a new TripleDES object.
TripleDES^ tripleDESalg = TripleDES::Create();
// Create a CryptoStream using the FileStream
// and the passed key and initialization vector (IV).
CryptoStream^ cStream = gcnew CryptoStream( fStream,tripleDESalg->CreateDecryptor( Key, IV ),CryptoStreamMode::Read );
// Create a StreamReader using the CryptoStream.
StreamReader^ sReader = gcnew StreamReader( cStream );
// Read the data from the stream
// to decrypt it.
String^ val = sReader->ReadLine();
// Close the streams and
// close the file.
sReader->Close();
cStream->Close();
fStream->Close();
// Return the string.
return val;
}
catch ( CryptographicException^ e )
{
Console::WriteLine( "A Cryptographic error occurred: {0}", e->Message );
return nullptr;
}
catch ( UnauthorizedAccessException^ e )
{
Console::WriteLine( "A file error occurred: {0}", e->Message );
return nullptr;
}
}
int main()
{
try
{
// Create a new TripleDES object to generate a key
// and initialization vector (IV). Specify one
// of the recognized simple names for this
// algorithm.
TripleDES^ TripleDESalg = TripleDES::Create( "TripleDES" );
// Create a string to encrypt.
String^ sData = "Here is some data to encrypt.";
String^ FileName = "CText.txt";
// Encrypt text to a file using the file name, key, and IV.
EncryptTextToFile( sData, FileName, TripleDESalg->Key, TripleDESalg->IV );
// Decrypt the text from a file using the file name, key, and IV.
String^ Final = DecryptTextFromFile( FileName, TripleDESalg->Key, TripleDESalg->IV );
// Display the decrypted string to the console.
Console::WriteLine( Final );
}
catch ( Exception^ e )
{
Console::WriteLine( e->Message );
}
}
using System;
using System.Security.Cryptography;
using System.Text;
using System.IO;
class TripleDESSample
{
static void Main()
{
try
{
// Create a new TripleDES object to generate a key
// and initialization vector (IV). Specify one
// of the recognized simple names for this
// algorithm.
TripleDES TripleDESalg = TripleDES.Create("TripleDES");
// Create a string to encrypt.
string sData = "Here is some data to encrypt.";
string FileName = "CText.txt";
// Encrypt text to a file using the file name, key, and IV.
EncryptTextToFile(sData, FileName, TripleDESalg.Key, TripleDESalg.IV);
// Decrypt the text from a file using the file name, key, and IV.
string Final = DecryptTextFromFile(FileName, TripleDESalg.Key, TripleDESalg.IV);
// Display the decrypted string to the console.
Console.WriteLine(Final);
}
catch (Exception e)
{
Console.WriteLine(e.Message);
}
}
public static void EncryptTextToFile(String Data, String FileName, byte[] Key, byte[] IV)
{
try
{
// Create or open the specified file.
FileStream fStream = File.Open(FileName,FileMode.OpenOrCreate);
// Create a new TripleDES object.
TripleDES tripleDESalg = TripleDES.Create();
// Create a CryptoStream using the FileStream
// and the passed key and initialization vector (IV).
CryptoStream cStream = new CryptoStream(fStream,
tripleDESalg.CreateEncryptor(Key,IV),
CryptoStreamMode.Write);
// Create a StreamWriter using the CryptoStream.
StreamWriter sWriter = new StreamWriter(cStream);
// Write the data to the stream
// to encrypt it.
sWriter.WriteLine(Data);
// Close the streams and
// close the file.
sWriter.Close();
cStream.Close();
fStream.Close();
}
catch(CryptographicException e)
{
Console.WriteLine("A Cryptographic error occurred: {0}", e.Message);
}
catch(UnauthorizedAccessException e)
{
Console.WriteLine("A file error occurred: {0}", e.Message);
}
}
public static string DecryptTextFromFile(String FileName, byte[] Key, byte[] IV)
{
try
{
// Create or open the specified file.
FileStream fStream = File.Open(FileName, FileMode.OpenOrCreate);
// Create a new TripleDES object.
TripleDES tripleDESalg = TripleDES.Create();
// Create a CryptoStream using the FileStream
// and the passed key and initialization vector (IV).
CryptoStream cStream = new CryptoStream(fStream,
tripleDESalg.CreateDecryptor(Key,IV),
CryptoStreamMode.Read);
// Create a StreamReader using the CryptoStream.
StreamReader sReader = new StreamReader(cStream);
// Read the data from the stream
// to decrypt it.
string val = sReader.ReadLine();
// Close the streams and
// close the file.
sReader.Close();
cStream.Close();
fStream.Close();
// Return the string.
return val;
}
catch(CryptographicException e)
{
Console.WriteLine("A Cryptographic error occurred: {0}", e.Message);
return null;
}
catch(UnauthorizedAccessException e)
{
Console.WriteLine("A file error occurred: {0}", e.Message);
return null;
}
}
}
Imports System.Security.Cryptography
Imports System.Text
Imports System.IO
Module TripleDESSample
Sub Main()
Try
' Create a new TripleDES object to generate a key
' and initialization vector (IV). Specify one
' of the recognized simple names for this
' algorithm.
Dim TripleDESalg As TripleDES = TripleDES.Create("TripleDES")
' Create a string to encrypt.
Dim sData As String = "Here is some data to encrypt."
Dim FileName As String = "CText.txt"
' Encrypt text to a file using the file name, key, and IV.
EncryptTextToFile(sData, FileName, TripleDESalg.Key, TripleDESalg.IV)
' Decrypt the text from a file using the file name, key, and IV.
Dim Final As String = DecryptTextFromFile(FileName, TripleDESalg.Key, TripleDESalg.IV)
' Display the decrypted string to the console.
Console.WriteLine(Final)
Catch e As Exception
Console.WriteLine(e.Message)
End Try
End Sub
Sub EncryptTextToFile(ByVal Data As String, ByVal FileName As String, ByVal Key() As Byte, ByVal IV() As Byte)
Try
' Create or open the specified file.
Dim fStream As FileStream = File.Open(FileName, FileMode.OpenOrCreate)
' Create a new TripleDES object.
Dim TripleDESalg As TripleDES = TripleDES.Create
' Create a CryptoStream using the FileStream
' and the passed key and initialization vector (IV).
Dim cStream As New CryptoStream(fStream, _
TripleDESalg.CreateEncryptor(Key, IV), _
CryptoStreamMode.Write)
' Create a StreamWriter using the CryptoStream.
Dim sWriter As New StreamWriter(cStream)
' Write the data to the stream
' to encrypt it.
sWriter.WriteLine(Data)
' Close the streams and
' close the file.
sWriter.Close()
cStream.Close()
fStream.Close()
Catch e As CryptographicException
Console.WriteLine("A Cryptographic error occurred: {0}", e.Message)
Catch e As UnauthorizedAccessException
Console.WriteLine("A file error occurred: {0}", e.Message)
End Try
End Sub
Function DecryptTextFromFile(ByVal FileName As String, ByVal Key() As Byte, ByVal IV() As Byte) As String
Try
' Create or open the specified file.
Dim fStream As FileStream = File.Open(FileName, FileMode.OpenOrCreate)
' Create a new TripleDES object.
Dim TripleDESalg As TripleDES = TripleDES.Create
' Create a CryptoStream using the FileStream
' and the passed key and initialization vector (IV).
Dim cStream As New CryptoStream(fStream, _
TripleDESalg.CreateDecryptor(Key, IV), _
CryptoStreamMode.Read)
' Create a StreamReader using the CryptoStream.
Dim sReader As New StreamReader(cStream)
' Read the data from the stream
' to decrypt it.
Dim val As String = sReader.ReadLine()
' Close the streams and
' close the file.
sReader.Close()
cStream.Close()
fStream.Close()
' Return the string.
Return val
Catch e As CryptographicException
Console.WriteLine("A Cryptographic error occurred: {0}", e.Message)
Return Nothing
Catch e As UnauthorizedAccessException
Console.WriteLine("A file error occurred: {0}", e.Message)
Return Nothing
End Try
End Function
End Module
次のコード例は、オブジェクトを作成して使用して、メモリ内の TripleDES データを暗号化および暗号化解除する方法を示しています。
using namespace System;
using namespace System::Security::Cryptography;
using namespace System::Text;
using namespace System::IO;
array<Byte>^ EncryptTextToMemory( String^ Data, array<Byte>^Key, array<Byte>^IV )
{
try
{
// Create a MemoryStream.
MemoryStream^ mStream = gcnew MemoryStream;
// Create a new TripleDES object.
TripleDES^ tripleDESalg = TripleDES::Create();
// Create a CryptoStream using the MemoryStream
// and the passed key and initialization vector (IV).
CryptoStream^ cStream = gcnew CryptoStream( mStream,tripleDESalg->CreateEncryptor( Key, IV ),CryptoStreamMode::Write );
// Convert the passed string to a byte array.
array<Byte>^toEncrypt = (gcnew ASCIIEncoding)->GetBytes( Data );
// Write the byte array to the crypto stream and flush it.
cStream->Write( toEncrypt, 0, toEncrypt->Length );
cStream->FlushFinalBlock();
// Get an array of bytes from the
// MemoryStream that holds the
// encrypted data.
array<Byte>^ret = mStream->ToArray();
// Close the streams.
cStream->Close();
mStream->Close();
// Return the encrypted buffer.
return ret;
}
catch ( CryptographicException^ e )
{
Console::WriteLine( "A Cryptographic error occurred: {0}", e->Message );
return nullptr;
}
}
String^ DecryptTextFromMemory( array<Byte>^Data, array<Byte>^Key, array<Byte>^IV )
{
try
{
// Create a new MemoryStream using the passed
// array of encrypted data.
MemoryStream^ msDecrypt = gcnew MemoryStream( Data );
// Create a new TripleDES object.
TripleDES^ tripleDESalg = TripleDES::Create();
// Create a CryptoStream using the MemoryStream
// and the passed key and initialization vector (IV).
CryptoStream^ csDecrypt = gcnew CryptoStream( msDecrypt,tripleDESalg->CreateDecryptor( Key, IV ),CryptoStreamMode::Read );
// Create buffer to hold the decrypted data.
array<Byte>^fromEncrypt = gcnew array<Byte>(Data->Length);
// Read the decrypted data out of the crypto stream
// and place it into the temporary buffer.
csDecrypt->Read( fromEncrypt, 0, fromEncrypt->Length );
//Convert the buffer into a string and return it.
return (gcnew ASCIIEncoding)->GetString( fromEncrypt );
}
catch ( CryptographicException^ e )
{
Console::WriteLine( "A Cryptographic error occurred: {0}", e->Message );
return nullptr;
}
}
int main()
{
try
{
// Create a new TripleDES object to generate a key
// and initialization vector (IV). Specify one
// of the recognized simple names for this
// algorithm.
TripleDES^ TripleDESalg = TripleDES::Create( "TripleDES" );
// Create a string to encrypt.
String^ sData = "Here is some data to encrypt.";
// Encrypt the string to an in-memory buffer.
array<Byte>^Data = EncryptTextToMemory( sData, TripleDESalg->Key, TripleDESalg->IV );
// Decrypt the buffer back to a string.
String^ Final = DecryptTextFromMemory( Data, TripleDESalg->Key, TripleDESalg->IV );
// Display the decrypted string to the console.
Console::WriteLine( Final );
}
catch ( Exception^ e )
{
Console::WriteLine( e->Message );
}
}
using System;
using System.Security.Cryptography;
using System.Text;
using System.IO;
class TripleDESSample2
{
static void Main()
{
try
{
byte[] key;
byte[] iv;
// Create a new TripleDES object to generate a random key
// and initialization vector (IV).
using (TripleDES tripleDes = TripleDES.Create())
{
key = tripleDes.Key;
iv = tripleDes.IV;
}
// Create a string to encrypt.
string original = "Here is some data to encrypt.";
// Encrypt the string to an in-memory buffer.
byte[] encrypted = EncryptTextToMemory(original, key, iv);
// Decrypt the buffer back to a string.
string decrypted = DecryptTextFromMemory(encrypted, key, iv);
// Display the decrypted string to the console.
Console.WriteLine(decrypted);
}
catch (Exception e)
{
Console.WriteLine(e.Message);
}
}
public static byte[] EncryptTextToMemory(string text, byte[] key, byte[] iv)
{
try
{
// Create a MemoryStream.
using (MemoryStream mStream = new MemoryStream())
{
// Create a new TripleDES object.
using (TripleDES tripleDes = TripleDES.Create())
// Create a TripleDES encryptor from the key and IV
using (ICryptoTransform encryptor = tripleDes.CreateEncryptor(key, iv))
// Create a CryptoStream using the MemoryStream and encryptor
using (var cStream = new CryptoStream(mStream, encryptor, CryptoStreamMode.Write))
{
// Convert the provided string to a byte array.
byte[] toEncrypt = Encoding.UTF8.GetBytes(text);
// Write the byte array to the crypto stream and flush it.
cStream.Write(toEncrypt, 0, toEncrypt.Length);
// Ending the using statement for the CryptoStream completes the encryption.
}
// Get an array of bytes from the MemoryStream that holds the encrypted data.
byte[] ret = mStream.ToArray();
// Return the encrypted buffer.
return ret;
}
}
catch (CryptographicException e)
{
Console.WriteLine("A Cryptographic error occurred: {0}", e.Message);
throw;
}
}
public static string DecryptTextFromMemory(byte[] encrypted, byte[] key, byte[] iv)
{
try
{
// Create a buffer to hold the decrypted data.
// TripleDES-encrypted data will always be slightly bigger than the decrypted data.
byte[] decrypted = new byte[encrypted.Length];
int offset = 0;
// Create a new MemoryStream using the provided array of encrypted data.
using (MemoryStream mStream = new MemoryStream(encrypted))
{
// Create a new TripleDES object.
using (TripleDES tripleDes = TripleDES.Create())
// Create a TripleDES decryptor from the key and IV
using (ICryptoTransform decryptor = tripleDes.CreateDecryptor(key, iv))
// Create a CryptoStream using the MemoryStream and decryptor
using (var cStream = new CryptoStream(mStream, decryptor, CryptoStreamMode.Read))
{
// Keep reading from the CryptoStream until it finishes (returns 0).
int read = 1;
while (read > 0)
{
read = cStream.Read(decrypted, offset, decrypted.Length - offset);
offset += read;
}
}
}
// Convert the buffer into a string and return it.
return Encoding.UTF8.GetString(decrypted, 0, offset);
}
catch (CryptographicException e)
{
Console.WriteLine("A Cryptographic error occurred: {0}", e.Message);
throw;
}
}
}
Imports System.Security.Cryptography
Imports System.Text
Imports System.IO
Module TripleDESPSample
Sub Main()
Try
' Create a new TripleDES object to generate a key
' and initialization vector (IV). Specify one
' of the recognized simple names for this
' algorithm.
Dim TripleDESalg As TripleDES = TripleDES.Create("TripleDES")
' Create a string to encrypt.
Dim sData As String = "Here is some data to encrypt."
' Encrypt the string to an in-memory buffer.
Dim Data As Byte() = EncryptTextToMemory(sData, TripleDESalg.Key, TripleDESalg.IV)
' Decrypt the buffer back to a string.
Dim Final As String = DecryptTextFromMemory(Data, TripleDESalg.Key, TripleDESalg.IV)
' Display the decrypted string to the console.
Console.WriteLine(Final)
Catch e As Exception
Console.WriteLine(e.Message)
End Try
End Sub
Function EncryptTextToMemory(ByVal Data As String, ByVal Key() As Byte, ByVal IV() As Byte) As Byte()
Try
' Create a MemoryStream.
Dim mStream As New MemoryStream
' Create a new TripleDES object.
Dim tripleDESalg As TripleDES = TripleDES.Create
' Create a CryptoStream using the MemoryStream
' and the passed key and initialization vector (IV).
Dim cStream As New CryptoStream(mStream, _
tripleDESalg.CreateEncryptor(Key, IV), _
CryptoStreamMode.Write)
' Convert the passed string to a byte array.
Dim toEncrypt As Byte() = New ASCIIEncoding().GetBytes(Data)
' Write the byte array to the crypto stream and flush it.
cStream.Write(toEncrypt, 0, toEncrypt.Length)
cStream.FlushFinalBlock()
' Get an array of bytes from the
' MemoryStream that holds the
' encrypted data.
Dim ret As Byte() = mStream.ToArray()
' Close the streams.
cStream.Close()
mStream.Close()
' Return the encrypted buffer.
Return ret
Catch e As CryptographicException
Console.WriteLine("A Cryptographic error occurred: {0}", e.Message)
Return Nothing
End Try
End Function
Function DecryptTextFromMemory(ByVal Data() As Byte, ByVal Key() As Byte, ByVal IV() As Byte) As String
Try
' Create a new MemoryStream using the passed
' array of encrypted data.
Dim msDecrypt As New MemoryStream(Data)
' Create a new TripleDES object.
Dim tripleDESalg As TripleDES = TripleDES.Create
' Create a CryptoStream using the MemoryStream
' and the passed key and initialization vector (IV).
Dim csDecrypt As New CryptoStream(msDecrypt, _
tripleDESalg.CreateDecryptor(Key, IV), _
CryptoStreamMode.Read)
' Create buffer to hold the decrypted data.
Dim fromEncrypt(Data.Length - 1) As Byte
' Read the decrypted data out of the crypto stream
' and place it into the temporary buffer.
csDecrypt.Read(fromEncrypt, 0, fromEncrypt.Length)
'Convert the buffer into a string and return it.
Return New ASCIIEncoding().GetString(fromEncrypt)
Catch e As CryptographicException
Console.WriteLine("A Cryptographic error occurred: {0}", e.Message)
Return Nothing
End Try
End Function
End Module