C鏣暗号解読クラスの実例プログラム
二年前に書いたものを整理して送ります。以前、会社はWebServiceをしなければなりませんでした。そして、WebServiceのSoappHeaderを暗号化しています。このクラスを使うには鍵の管理が必要です。データの安全性を保証するためには、データを暗号化しがちですが、暗号化の欠点の一つは、プログラムの動作効率に影響を与えます。だから、ユーザの登録情報（ユーザ名、パスワード）だけを暗号化するという考えです。データは平文で伝送され、ユーザ情報の検証が通らなかった場合、データ転送は行われません。実際には、ネットワーク通信において、秘密鍵を使用する方法は完璧ではありません。もしハッカーが鍵で暗号化されたものを捉え、ユーザーが情報を検証し、その後、シミュレーション要求を行い、WebServiceを提供するサーバに要求を送ることができますか？それとも要求データを得ることができますか？だから、私はまたIPあるいはドメインのバインディングの方式を使いました！結局、WebServiceは最終ユーザーに直接提供したのではないです。このような手段を加えると、不良な意図者が不正にWebServiceのサービスを獲得したいと思っても、もうちょっと苦労しましょう。もう一つの安全提案があります。定期的に鍵を交換します。この例では対称暗号を使っています。暗号化者と暗号解読者の鍵は一致しています。定期的に鍵を交換すると、安全性が向上します。みんなはもっと良い方法があって、あるいは提案があって、伝言を残して討論することができます！共に向上します！
コードは以下の通りです
コードは以下の通りです
using System;
using System.Security.Cryptography;
using System.Text;
using System.IO;
namespace SEDO
{
/// <summary>
/// SEDO 。
/// SEDO 4 (Des,Rc2,Rijndael,TripleDes)
///
/// ：
/// 1:TripleDes Rijndael / 16 24 byte Key
/// 2:Rijndael 16 IV
/// 3:Des Rc2 8 Byte Key IV
/// 4: / / ，
/// 5: IV
/// ： 2010-10-30 [email protected]
/// </summary>
//
public enum EncryptionAlgorithm { Des = 1, Rc2, Rijndael, TripleDes };
//
internal class EncryptTransformer
{
private EncryptionAlgorithm algorithmID;
private byte[] initVec;
private byte[] encKey;
internal EncryptTransformer(EncryptionAlgorithm algId)
{
//Save the algorithm being used.
algorithmID = algId;
}
internal ICryptoTransform GetCryptoServiceProvider(byte[] bytesKey)
{
// Key IV ，
// Key IV
switch (algorithmID)
{
case EncryptionAlgorithm.Des:
{
DES des = new DESCryptoServiceProvider();
des.Mode = CipherMode.CBC;
// See if a key was provided
if (null == bytesKey)
{
encKey = des.Key;
}
else
{
des.Key = bytesKey;
encKey = des.Key;
}
// See if the client provided an initialization vector
if (null == initVec)
{ // Have the algorithm create one
initVec = des.IV;
}
else
{ //No, give it to the algorithm
des.IV = initVec;
}
return des.CreateEncryptor();
}
case EncryptionAlgorithm.TripleDes:
{
TripleDES des3 = new TripleDESCryptoServiceProvider();
des3.Mode = CipherMode.CBC;
// See if a key was provided
if (null == bytesKey)
{
encKey = des3.Key;
}
else
{
des3.Key = bytesKey;
encKey = des3.Key;
}
// See if the client provided an IV
if (null == initVec)
{ //Yes, have the alg create one
initVec = des3.IV;
}
else
{ //No, give it to the alg.
des3.IV = initVec;
}
return des3.CreateEncryptor();
}
case EncryptionAlgorithm.Rc2:
{
RC2 rc2 = new RC2CryptoServiceProvider();
rc2.Mode = CipherMode.CBC;
// Test to see if a key was provided
if (null == bytesKey)
{
encKey = rc2.Key;
}
else
{
rc2.Key = bytesKey;
encKey = rc2.Key;
}
// See if the client provided an IV
if (null == initVec)
{ //Yes, have the alg create one
initVec = rc2.IV;
}
else
{ //No, give it to the alg.
rc2.IV = initVec;
}
return rc2.CreateEncryptor();
}
case EncryptionAlgorithm.Rijndael:
{
Rijndael rijndael = new RijndaelManaged();
rijndael.Mode = CipherMode.CBC;
// Test to see if a key was provided
if (null == bytesKey)
{
encKey = rijndael.Key;
}
else
{
rijndael.Key = bytesKey;
encKey = rijndael.Key;
}
// See if the client provided an IV
if (null == initVec)
{ //Yes, have the alg create one
initVec = rijndael.IV;
}
else
{ //No, give it to the alg.
rijndael.IV = initVec;
}
return rijndael.CreateEncryptor();
}
default:
{
throw new CryptographicException("Algorithm ID '" +
algorithmID +
"' not supported.");
}
}
}
//
internal byte[] IV
{
get { return initVec; }
set { initVec = value; }
}
//
internal byte[] Key
{
get { return encKey; }
set { encKey = value; }
}
}
//
internal class DecryptTransformer
{
private EncryptionAlgorithm algorithmID;
private byte[] initVec;
private byte[] encKey;
internal DecryptTransformer(EncryptionAlgorithm deCryptId)
{
algorithmID = deCryptId;
}
//
internal byte[] IV
{
get { return initVec; }
set { initVec = value; }
}
//
internal byte[] Key
{
get { return encKey; }
set { encKey = value; }
}
internal ICryptoTransform GetCryptoServiceProvider(byte[] bytesKey)
{
// Key IV ，
// Key IV
switch (algorithmID)
{
case EncryptionAlgorithm.Des:
{
DES des = new DESCryptoServiceProvider();
des.Mode = CipherMode.CBC;
des.Key = bytesKey;
des.IV = initVec;
return des.CreateDecryptor();
}
case EncryptionAlgorithm.TripleDes:
{
TripleDES des3 = new TripleDESCryptoServiceProvider();
des3.Mode = CipherMode.CBC;
return des3.CreateDecryptor(bytesKey, initVec);
}
case EncryptionAlgorithm.Rc2:
{
RC2 rc2 = new RC2CryptoServiceProvider();
rc2.Mode = CipherMode.CBC;
return rc2.CreateDecryptor(bytesKey, initVec);
}
case EncryptionAlgorithm.Rijndael:
{
Rijndael rijndael = new RijndaelManaged();
rijndael.Mode = CipherMode.CBC;
return rijndael.CreateDecryptor(bytesKey, initVec);
}
default:
{
throw new CryptographicException("Algorithm ID '" +
algorithmID +
"' not supported.");
}
}
} //end GetCryptoServiceProvider
}
//
public class Encryptor
{
private EncryptTransformer transformer;
private byte[] initVec;
private byte[] encKey;
public Encryptor(EncryptionAlgorithm algId)
{
transformer = new EncryptTransformer(algId);
}
public byte[] Encrypt(byte[] bytesData, byte[] bytesKey, byte[] bytesIV)
{
// .
MemoryStream memStreamEncryptedData = new MemoryStream();
transformer.IV = bytesIV;
transformer.Key = bytesKey;
ICryptoTransform transform =
transformer.GetCryptoServiceProvider(bytesKey);
CryptoStream encStream =
new CryptoStream(memStreamEncryptedData,
transform, CryptoStreamMode.Write);
try
{
//
encStream.Write(bytesData, 0, bytesData.Length);
}
catch (Exception ex)
{
throw new Exception(" ！"+
" ：
" + ex.Message);
}
// Key IV
encKey = transformer.Key;
initVec = transformer.IV;
encStream.FlushFinalBlock();
encStream.Close();
//Send the data back.
return memStreamEncryptedData.ToArray();
}
public byte[] IV
{
get { return initVec; }
set { initVec = value; }
}
public byte[] Key
{
get { return encKey; }
set { encKey = value; }
}
}
//
public class Decryptor
{
private DecryptTransformer transformer;
private byte[] initVec;
private byte[] encKey;
public Decryptor(EncryptionAlgorithm algId)
{
transformer = new DecryptTransformer(algId);
}
public byte[] Decrypt(byte[] bytesData,
byte[] bytesKey, byte[] bytesIV)
{
// .
MemoryStream memStreamDecryptedData =
new MemoryStream();
//Pass in the initialization vector.
transformer.IV = bytesIV;
transformer.Key = bytesKey;
ICryptoTransform transform =
transformer.GetCryptoServiceProvider(bytesKey);
CryptoStream decStream =
new CryptoStream(memStreamDecryptedData,
transform, CryptoStreamMode.Write);
try
{
decStream.Write(bytesData, 0, bytesData.Length);
}
catch (Exception ex)
{
throw new Exception(" ！"+
" ：
" + ex.Message);
}
decStream.FlushFinalBlock();
decStream.Close();
// .
return memStreamDecryptedData.ToArray();
}
public byte[] IV
{
get { return initVec; }
set { initVec = value; }
}
public byte[] Key
{
get { return encKey; }
set { encKey = value; }
}
}
// ： /
public class SecurityFile
{
private DecryptTransformer Dec_Transformer; //
private EncryptTransformer Enc_Transformer; //
private byte[] initVec;
private byte[] encKey;
public SecurityFile(EncryptionAlgorithm algId)
{
Dec_Transformer = new DecryptTransformer(algId);
Enc_Transformer = new EncryptTransformer(algId);
}
//
internal byte[] IV
{
get { return initVec; }
set { initVec = value; }
}
//
internal byte[] Key
{
get { return encKey; }
set { encKey = value; }
}
// ：
public void EncryptFile(string inFileName,
string outFileName, byte[] bytesKey, byte[] bytesIV)
{
try
{
FileStream fin =
new FileStream(inFileName, FileMode.Open,
FileAccess.Read);
FileStream fout = new FileStream(outFileName,
FileMode.OpenOrCreate, FileAccess.Write);
fout.SetLength(0);
//Create variables to help with read and write.
//This is intermediate storage for the encryption.
byte[] bin = new byte[100];
//This is the total number of bytes written.
long rdlen = 0;
//This is the total length of the input file.
long totlen = fin.Length;
//This is the number of bytes to be written at a time.
int len;
Enc_Transformer.IV = bytesIV;
Enc_Transformer.Key = bytesKey;
ICryptoTransform transform =
Enc_Transformer.GetCryptoServiceProvider(bytesKey);
CryptoStream encStream =
new CryptoStream(fout, transform, CryptoStreamMode.Write);
//Read from the input file, then encrypt and write to the output file.
while (rdlen < totlen)
{
len = fin.Read(bin, 0, 100);
encStream.Write(bin, 0, len);
rdlen = rdlen + len;
}
encStream.Close();
fout.Close();
fin.Close();
}
catch (Exception ex)
{
throw new Exception(" ！"+
" ：
" + ex.Message);
}
}
// ：
public void DecryptFile(string inFileName,
string outFileName, byte[] bytesKey, byte[] bytesIV)
{
try
{
FileStream fin =
new FileStream(inFileName, FileMode.Open,
FileAccess.Read);
FileStream fout =
new FileStream(outFileName,
FileMode.OpenOrCreate, FileAccess.Write);
fout.SetLength(0);
//Create variables to help with read and write.
//This is intermediate storage for the encryption.
byte[] bin = new byte[100];
//This is the total number of bytes written.
long rdlen = 0;
//This is the total length of the input file.
long totlen = fin.Length;
//This is the number of bytes to be written at a time.
int len;
Dec_Transformer.IV = bytesIV;
Dec_Transformer.Key = bytesKey;
ICryptoTransform transform =
Dec_Transformer.GetCryptoServiceProvider(bytesKey);
CryptoStream encStream =
new CryptoStream(fout, transform, CryptoStreamMode.Write);
//Read from the input file, then encrypt and
//write to the output file.
while (rdlen < totlen)
{
len = fin.Read(bin, 0, 100);
encStream.Write(bin, 0, len);
rdlen = rdlen + len;
}
encStream.Close();
fout.Close();
fin.Close();
}
catch (Exception ex)
{
throw new Exception(" "+
" ！ ：
" + ex.Message);
}
}
}
}