前兩年寫的東西，現在整理一下發出來！以前公司需要做WebService，并且對WebService的SoapHeader進行加密，所以就寫了這么個東東！使用這個類，需要密鑰管理！為了保證數據的安全性往往要對數據進行加密，但是加密的缺點之一，就是影響程序的運行效率，所以，當時我的思路是只對用戶的登錄信息（用戶名，密碼）進行加密！數據用明文傳輸，用戶信息驗證沒有通過的情況下, 不進行數據傳輸。
實際在網絡通訊中，使用密鑰匙的方式并非無懈可擊，如果黑客可以捕捉到用密鑰加密的，用戶驗證信息，然后，做個模擬請求，向提供WebService的服務器發請求，還是可以獲得請求數據！所以，我又使用了IP或者域名綁定的方式！畢竟，WebService不是直接對最終用戶提供的！所以，加上以上這些手段后，就算有不良企圖者想通過非法方式獲得WebService提供的服務，就再費點勁吧！
還有一點安全建議，就是定期的更換密鑰，在這個例子中，我用的是對稱加密，加密方和解密方的密鑰一致！定期的更換密鑰可以讓安全性提高一大截！
大家要有更好的方法，或者建議，可以留言討論一下！共同提高！
代碼如下：
using System;
using System.Security.Cryptography;
using System.Text;
using System.IO;
namespace SEDO
{
/// <summary>
/// SEDO 的摘要說明。
/// SEDO 實現的是用一個封裝了4種對稱加密方法(Des,Rc2,Rijndael,TripleDes)的組件
///
/// 注意事項：
/// 1:TripleDes和Rijndael加密/解密對象使用16或者24位byte的Key
/// 2:Rijndael只能使用16位的初始化向量IV
/// 3:Des和Rc2均使用8位Byte的Key和IV
/// 4:對需要加密/解密的數據流采用何種方法進行編碼/解碼，由調用組件的用戶自己決定
/// 5:密鑰和初始化向量IV由使用者自己定義
/// 程序員： 羅旭成2010-10-30 lxc880615@163.com
/// </summary>
//定義加密類型的枚舉
public enum EncryptionAlgorithm { Des = 1, Rc2, Rijndael, TripleDes };
//定義加密類
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)
{
//當數據密鑰Key或者初始化向量IV為空的時候，
//將使用加密對象自動產生的密鑰Key或者初始化向量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.");
}
}
}
//加密的偏移向量
internal byte[] IV
{
get { return initVec; }
set { initVec = value; }
}
//加密的密鑰
internal byte[] Key
{
get { return encKey; }
set { encKey = value; }
}
}
//定義解密類
internal class DecryptTransformer
{
private EncryptionAlgorithm algorithmID;
private byte[] initVec;
private byte[] encKey;
internal DecryptTransformer(EncryptionAlgorithm deCryptId)
{
algorithmID = deCryptId;
}
//加密的偏移向量
internal byte[] IV
{
get { return initVec; }
set { initVec = value; }
}
//加密的密鑰
internal byte[] Key
{
get { return encKey; }
set { encKey = value; }
}
internal ICryptoTransform GetCryptoServiceProvider(byte[] bytesKey)
{
//當數據密鑰Key或者初始化向量IV為空的時候，
//將使用加密對象自動產生的密鑰Key或者初始化向量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
}
//定義加密者類
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)
{
//設置流對象用來保存加密數據字節流.
MemoryStream memStreamEncryptedData = new MemoryStream();
transformer.IV = bytesIV;
transformer.Key = bytesKey;
ICryptoTransform transform =
transformer.GetCryptoServiceProvider(bytesKey);
CryptoStream encStream =
new CryptoStream(memStreamEncryptedData,
transform, CryptoStreamMode.Write);
try
{
//將加密數據寫進流對象
encStream.Write(bytesData, 0, bytesData.Length);
}
catch (Exception ex)
{
throw new Exception("在數據加密的時候出現錯誤！"+
"錯誤提示： /n" + ex.Message);
}
//設置加密的Key和初始向量IV屬性
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; }
}
}
//定義解密者類
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)
{
//設置流對象用來保存解密數據字節流.
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("在數據解密的時候出現錯誤！"+
"錯誤提示： /n" + ex.Message);
}
decStream.FlushFinalBlock();
decStream.Close();
// 返回解密數據.
return memStreamDecryptedData.ToArray();
}
public byte[] IV
{
get { return initVec; }
set { initVec = value; }
}
public byte[] Key
{
get { return encKey; }
set { encKey = value; }
}
}
//類描述：文件加密/解密類
public class SecurityFile
{
private DecryptTransformer Dec_Transformer; //解密轉換器
private EncryptTransformer Enc_Transformer; //加密轉換器
private byte[] initVec;
private byte[] encKey;
public SecurityFile(EncryptionAlgorithm algId)
{
Dec_Transformer = new DecryptTransformer(algId);
Enc_Transformer = new EncryptTransformer(algId);
}
//加密的偏移向量
internal byte[] IV
{
get { return initVec; }
set { initVec = value; }
}
//加密的密鑰
internal byte[] Key
{
get { return encKey; }
set { encKey = value; }
}
//功能描述：加密文件
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("在文件加密的時候出現錯誤！"+
"錯誤提示： /n" + ex.Message);
}
}
//功能描述：解密文件
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("在文件加密的時候出現"+
"錯誤！錯誤提示： /n" + ex.Message);
}
}
}
}
