c# – Rfc2898DeriveBytes如何验证存储在数据库中的密码作为哈希值
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如何验证存储在数据库中的密码作为哈希值
当我用数据库值验证密码哈希时,它将永远不会相同,因为它会生成随机盐.
如何附加盐以验证和测试.
下面是我用于散列的代码并验证散列密码.
我的代码:
/// <summary>
/// Generate the value from bytes.
/// </summary>
/// <param name="password"></param>
/// <param name="iterationCount"></param>
/// <returns></returns>
private static string GenerateHashValue(string password)
{
return Convert.ToBase64String(GenerateHashBytes(password));
}
/// <summary>
/// Hashing the password using PBKDF2
/// </summary>
/// <param name="password"></param>
/// <param name="iterationCount"></param>
/// <returns></returns>
private static byte[] GenerateHashBytes(string password)
{
byte[] hashValue;
//create salt
byte[] salt = GenerateRandomSalt();
var valueToHash = string.IsNullOrEmpty(password) ? string.Empty : password;
using (var pbkdf2 = new Rfc2898DeriveBytes(valueToHash,salt, iterationCount))
{
hashValue = pbkdf2.GetBytes(DerivedKeyLength);
}
return hashValue;
}
public static bool VerifyPassword(string password, string correctHash)
{
byte[] hash;
byte[] OriginalHash = Encoding.ASCII.GetBytes(correctHash);
hash = GenerateHashBytes(password);
return SlowEquals(hash, OriginalHash);
}
private static bool SlowEquals(byte[] a, byte[] b)
{
var diff = (uint)a.Length ^ (uint)b.Length;
for (int i = 0; i < a.Length && i < b.Length; i++)
{
diff |= (uint)(a[i] ^ b[i]);
}
return diff == 0;
}
/// <summary>
/// Used to generate the random string to append hash.
/// </summary>
/// <returns></returns>
private static byte[] GenerateRandomSalt()
{
/*We are using the RNGCryptoServiceProvider class to create a Cryptography Secure Pseudo-Random Number Generator that will generate the level of randomness and uniqueness we require for a salt.*/
var csprng = new RNGCryptoServiceProvider();
var salt = new byte[SaltByteLength];
csprng.GetBytes(salt);
return salt;
}
解决方法:
您将不得不创建一个salt并将其与密码哈希一起存储在您的数据库中.
在对密码进行哈希处理时,您从DB请求用户X(或其他)的salt,检查它是否存在,并将salt应用于哈希.
它看起来像这样(伪代码带有一些你提供的代码):
var salt = GetSaltFromDB();
if (salt == null) //Not yet in DB
salt = GenerateSalt(); //This also saves the salt to DB
using (var pbkdf2 = new Rfc2898DeriveBytes(valueToHash, salt, iterationCount))
{
hashValue = pbkdf2.GetBytes(DerivedKeyLength);
}
标签:c,hash,password-hash,string-hashing 来源: https://codeday.me/bug/20190627/1306233.html