我目前正在开发一项网络服务。作为此Web服务的一部分，我能够在SQL DB中安全地存储用户密码，并能够通过HTTPS Web服务将密码值解密到最终用户。
这是我第一次处理这个要求。我找到了很多基于对称和/或非对称加密的例子。但是我不明白永久存储用于加密数据的密码/密钥。
例如，如果我使用基于RijndaelManaged的对称加密，如何安全地存储用于加密的输入参数，以便我的Web服务稍后可以检索SQL DB的数据，并解密它们。
答案 0 :(得分：3)
将用户密码安全地存储在SQL DB中，并且能够解密 密码值
这不安全。密码永远不应加密;他们应该 哈希 ！加盐和hashing algorithm that is suited for pashword hashing。
答案 1 :(得分：1)
使用此：
public class Crypto
{
#region enums, constants & fields
//types of symmetric encyption
public enum CryptoTypes
{
encTypeDES = 0,
encTypeRC2,
encTypeRijndael,
encTypeTripleDES
}
private const string CRYPT_DEFAULT_PASSWORD = "yourDefaultPassword"; //"CB06cfE507a1";
private const CryptoTypes CRYPT_DEFAULT_METHOD = CryptoTypes.encTypeRijndael;
private byte[] mKey = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24};
private byte[] mIV = {65, 110, 68, 26, 69, 178, 200, 219};
private byte[] SaltByteArray = {0x49, 0x76, 0x61, 0x6e, 0x20, 0x4d, 0x65, 0x64, 0x76, 0x65, 0x64, 0x65, 0x76};
private CryptoTypes mCryptoType = CRYPT_DEFAULT_METHOD;
private string mPassword = CRYPT_DEFAULT_PASSWORD;
#endregion
#region Constructors
public Crypto()
{
calculateNewKeyAndIV();
}
public Crypto(CryptoTypes CryptoType)
{
this.CryptoType = CryptoType;
}
#endregion
#region Props
/// <summary>
/// type of encryption / decryption used
/// </summary>
public CryptoTypes CryptoType
{
get
{
return mCryptoType;
}
set
{
if (mCryptoType != value)
{
mCryptoType = value;
calculateNewKeyAndIV();
}
}
}
/// <summary>
/// Passsword Key Property.
/// The password key used when encrypting / decrypting
/// </summary>
public string Password
{
get
{
return mPassword;
}
set
{
if (mPassword != value)
{
mPassword = value;
calculateNewKeyAndIV();
}
}
}
#endregion
#region Encryption
/// <summary>
/// Encrypt a string
/// </summary>
/// <param storeName="inputText">text to encrypt</param>
/// <returns>an encrypted string</returns>
public string Encrypt(string inputText)
{
//declare a new encoder
UTF8Encoding UTF8Encoder = new UTF8Encoding();
//get byte representation of string
byte[] inputBytes = UTF8Encoder.GetBytes(inputText);
//convert back to a string
return Convert.ToBase64String(EncryptDecrypt(inputBytes,true));
}
/// <summary>
/// Encrypt string with user defined password
/// </summary>
/// <param storeName="inputText">text to encrypt</param>
/// <param storeName="password">password to use when encrypting</param>
/// <returns>an encrypted string</returns>
public string Encrypt(string inputText, string password)
{
this.Password = password;
return this.Encrypt(inputText);
}
/// <summary>
/// Encrypt string acc. to cryptoType and with user defined password
/// </summary>
/// <param storeName="inputText">text to encrypt</param>
/// <param storeName="password">password to use when encrypting</param>
/// <param storeName="cryptoType">type of encryption</param>
/// <returns>an encrypted string</returns>
public string Encrypt(string inputText, string password, CryptoTypes cryptoType)
{
mCryptoType = cryptoType;
return this.Encrypt(inputText,password);
}
/// <summary>
/// Encrypt string acc. to cryptoType
/// </summary>
/// <param storeName="inputText">text to encrypt</param>
/// <param storeName="cryptoType">type of encryption</param>
/// <returns>an encrypted string</returns>
public string Encrypt(string inputText, CryptoTypes cryptoType)
{
this.CryptoType = cryptoType;
return this.Encrypt(inputText);
}
#endregion
#region Decryption
/// <summary>
/// decrypts a string
/// </summary>
/// <param storeName="inputText">string to decrypt</param>
/// <returns>a decrypted string</returns>
public string Decrypt(string inputText)
{
//declare a new encoder
UTF8Encoding UTF8Encoder = new UTF8Encoding();
//get byte representation of string
byte[] inputBytes = Convert.FromBase64String(inputText);
//convert back to a string
return UTF8Encoder.GetString(EncryptDecrypt(inputBytes,false));
}
/// <summary>
/// decrypts a string using a user defined password key
/// </summary>
/// <param storeName="inputText">string to decrypt</param>
/// <param storeName="password">password to use when decrypting</param>
/// <returns>a decrypted string</returns>
public string Decrypt(string inputText, string password)
{
this.Password = password;
return Decrypt(inputText);
}
/// <summary>
/// decrypts a string acc. to decryption type and user defined password key
/// </summary>
/// <param storeName="inputText">string to decrypt</param>
/// <param storeName="password">password key used to decrypt</param>
/// <param storeName="cryptoType">type of decryption</param>
/// <returns>a decrypted string</returns>
public string Decrypt(string inputText, string password, CryptoTypes cryptoType)
{
mCryptoType = cryptoType;
return Decrypt(inputText,password);
}
/// <summary>
/// decrypts a string acc. to the decryption type
/// </summary>
/// <param storeName="inputText">string to decrypt</param>
/// <param storeName="cryptoType">type of decryption</param>
/// <returns>a decrypted string</returns>
public string Decrypt(string inputText, CryptoTypes cryptoType)
{
this.CryptoType = cryptoType;
return Decrypt(inputText);
}
#endregion
#region Symmetric Engine
/// <summary>
/// performs the actual enc/dec.
/// </summary>
/// <param storeName="inputBytes">input byte array</param>
/// <param storeName="Encrpyt">wheather or not to perform enc/dec</param>
/// <returns>byte array output</returns>
private byte[] EncryptDecrypt(byte[] inputBytes, bool Encrpyt)
{
//get the correct transform
ICryptoTransform transform = getCryptoTransform(Encrpyt);
//memory stream for output
MemoryStream memStream = new MemoryStream();
try
{
//setup the cryption - output written to memstream
CryptoStream cryptStream = new CryptoStream(memStream,transform,CryptoStreamMode.Write);
//write data to cryption engine
cryptStream.Write(inputBytes,0,inputBytes.Length);
//we are finished
cryptStream.FlushFinalBlock();
//get result
byte[] output = memStream.ToArray();
//finished with engine, so close the stream
cryptStream.Close();
return output;
}
catch (Exception e)
{
//throw an error
throw new Exception("Error in symmetric engine. Error : " + e.Message,e);
}
}
/// <summary>
/// returns the symmetric engine and creates the encyptor/decryptor
/// </summary>
/// <param storeName="encrypt">whether to return a encrpytor or decryptor</param>
/// <returns>ICryptoTransform</returns>
private ICryptoTransform getCryptoTransform(bool encrypt)
{
SymmetricAlgorithm SA = selectAlgorithm();
SA.Key = mKey;
SA.IV = mIV;
if (encrypt)
{
return SA.CreateEncryptor();
}else
{
return SA.CreateDecryptor();
}
}
/// <summary>
/// returns the specific symmetric algorithm acc. to the cryptotype
/// </summary>
/// <returns>SymmetricAlgorithm</returns>
private SymmetricAlgorithm selectAlgorithm()
{
SymmetricAlgorithm SA;
switch (mCryptoType)
{
case CryptoTypes.encTypeDES:
SA = DES.Create();
break;
case CryptoTypes.encTypeRC2:
SA = RC2.Create();
break;
case CryptoTypes.encTypeRijndael:
SA = Rijndael.Create();
break;
case CryptoTypes.encTypeTripleDES:
SA = TripleDES.Create();
break;
default:
SA = TripleDES.Create();
break;
}
return SA;
}
/// <summary>
/// calculates the key and IV acc. to the symmetric method from the password
/// key and IV size dependant on symmetric method
/// </summary>
private void calculateNewKeyAndIV()
{
//use salt so that key cannot be found with dictionary attack
PasswordDeriveBytes pdb = new PasswordDeriveBytes(mPassword,SaltByteArray);
SymmetricAlgorithm algo = selectAlgorithm();
mKey = pdb.GetBytes(algo.KeySize / 8);
mIV = pdb.GetBytes(algo.BlockSize / 8);
}
#endregion
}
/// <summary>
/// Hashing class. Only static members so no need to create an instance
/// </summary>
public class Hashing
{
#region enum, constants and fields
//types of hashing available
public enum HashingTypes
{
SHA, SHA256, SHA384, SHA512, MD5
}
#endregion
#region static members
public static string Hash(String inputText)
{
return ComputeHash(inputText,HashingTypes.MD5);
}
public static string Hash(String inputText, HashingTypes hashingType)
{
return ComputeHash(inputText,hashingType);
}
/// <summary>
/// returns true if the input text is equal to hashed text
/// </summary>
/// <param storeName="inputText">unhashed text to test</param>
/// <param storeName="hashText">already hashed text</param>
/// <returns>boolean true or false</returns>
public static bool isHashEqual(string inputText, string hashText)
{
return (Hash(inputText) == hashText);
}
public static bool isHashEqual(string inputText, string hashText, HashingTypes hashingType)
{
return (Hash(inputText,hashingType) == hashText);
}
#endregion
#region Hashing Engine
/// <summary>
/// computes the hash code and converts it to string
/// </summary>
/// <param storeName="inputText">input text to be hashed</param>
/// <param storeName="hashingType">type of hashing to use</param>
/// <returns>hashed string</returns>
private static string ComputeHash(string inputText, HashingTypes hashingType)
{
HashAlgorithm HA = getHashAlgorithm(hashingType);
//declare a new encoder
UTF8Encoding UTF8Encoder = new UTF8Encoding();
//get byte representation of input text
byte[] inputBytes = UTF8Encoder.GetBytes(inputText);
//hash the input byte array
byte[] output = HA.ComputeHash(inputBytes);
//convert output byte array to a string
return Convert.ToBase64String(output);
}
/// <summary>
/// returns the specific hashing alorithm
/// </summary>
/// <param storeName="hashingType">type of hashing to use</param>
/// <returns>HashAlgorithm</returns>
private static HashAlgorithm getHashAlgorithm(HashingTypes hashingType)
{
switch (hashingType)
{
case HashingTypes.MD5 :
return new MD5CryptoServiceProvider();
case HashingTypes.SHA :
return new SHA1CryptoServiceProvider();
case HashingTypes.SHA256 :
return new SHA256Managed();
case HashingTypes.SHA384 :
return new SHA384Managed();
case HashingTypes.SHA512 :
return new SHA512Managed();
default :
return new MD5CryptoServiceProvider();
}
}
#endregion
}
您可以使用加密和解密方法进行加密和解密
我在我的项目中使用了这个......