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Can't Verify Hash Password in C#

In C# language, my purpose is to hash password with hash_password(), then verify it with verify() methods. I hash and salt for password 's3cr3t', then check for two examples and return true if password is 's3cr3t' and return false for password 's3cr4t'.
using System;
using System.Text;
using System.Security.Cryptography;
public class Pbkdf2_test4
{
public const int salt_size = 24;
public const int hash_size = 24;
public const int iteration = 100000;
static byte[] salt1 = new byte[salt_size];
private static Rfc2898DeriveBytes hash_password(string password)
{
RandomNumberGenerator generator = RandomNumberGenerator.Create();
byte[] salt = new byte[salt_size];
generator.GetBytes(salt);
salt1 = salt;
Rfc2898DeriveBytes pbkdf2 = new Rfc2898DeriveBytes(password, salt1, iteration);
return pbkdf2;
}
private static bool verify(Rfc2898DeriveBytes pw_hash, string password)
{
//data1 can be a string or contents of a file.
string data1 = "Some test data";
try
{
Rfc2898DeriveBytes k1 = pw_hash;
Rfc2898DeriveBytes k2 = new Rfc2898DeriveBytes(password, salt1, iteration);
// Encrypt the data.
Aes encAlg = Aes.Create();
encAlg.Key = k1.GetBytes(16);
MemoryStream encryptionStream = new MemoryStream();
CryptoStream encrypt = new CryptoStream(encryptionStream, encAlg.CreateEncryptor(), CryptoStreamMode.Write);
byte[] utfD1 = new System.Text.UTF8Encoding(false).GetBytes(data1);
encrypt.Write(utfD1, 0, utfD1.Length);
encrypt.FlushFinalBlock();
encrypt.Close();
byte[] edata1 = encryptionStream.ToArray();
k1.Reset();
// Try to decrypt, thus showing it can be round-tripped.
Aes decAlg = Aes.Create();
decAlg.Key = k2.GetBytes(16);
decAlg.IV = encAlg.IV;
MemoryStream decryptionStreamBacking = new MemoryStream();
CryptoStream decrypt = new CryptoStream(decryptionStreamBacking, decAlg.CreateDecryptor(), CryptoStreamMode.Write);
decrypt.Write(edata1, 0, edata1.Length);
decrypt.Flush();
decrypt.Close();
k2.Reset();
string data2 = new UTF8Encoding(false).GetString(decryptionStreamBacking.ToArray());
if (!data1.Equals(data2))
{
return false;
}
else
{
return true;
}
}
catch (Exception e)
{
return false;
}
}
public static void Run()
{
Rfc2898DeriveBytes pw_hash = hash_password("s3cr3t");
Console.WriteLine(System.Text.Encoding.UTF8.GetString(pw_hash.GetBytes(hash_size)));
var result1 = verify(pw_hash, "s3cr3t");
Console.WriteLine(result1);
var result2 = verify(pw_hash, "s3cr4t");
Console.WriteLine(result2);
}
}
My question, somehow there is a problem that for verify(pw_hash, "s3cr3t") that returns false however it should return true. In verify(), there is a problem but still could not understand because I give keys k1 and k2 true, but still does not receive hash/salt same, how can I fix this problem?
Apart from this, shuld I add anything to make password storage safest?

Here is program to encrypt and decrypt pass
internal class Program
{
static void Main(string[] args)
{
Pbkdf2_test4 test4 = new Pbkdf2_test4();
test4.Run();
Console.ReadLine();
}
}
public class Pbkdf2_test4
{
static string key = string.Empty;
static string iv = string.Empty;
public Pbkdf2_test4()
{
Aes encAlg = Aes.Create();
encAlg.GenerateKey();
key = Convert.ToBase64String(encAlg.Key);
encAlg.GenerateIV();
iv = Convert.ToBase64String(encAlg.IV);
}
public string Encrypt(string plainText, string Key, string IV)
{
// Check arguments.
if (string.IsNullOrWhiteSpace(plainText))
throw new ArgumentNullException(nameof(plainText));
if (string.IsNullOrWhiteSpace(Key))
throw new ArgumentNullException(nameof(Key));
if (string.IsNullOrWhiteSpace(IV))
throw new ArgumentNullException(nameof(IV));
byte[] encrypted;
// Create an AesCryptoServiceProvider object
// with the specified key and IV.
using (Aes aes = Aes.Create())
{
aes.Key = Convert.FromBase64String(Key);
aes.IV = Convert.FromBase64String(IV);
// Create an encrypt-or to perform the stream transform.
ICryptoTransform encryptor = aes.CreateEncryptor(aes.Key, aes.IV);
// Create the streams used for encryption.
using (MemoryStream msEncrypt = new MemoryStream())
{
using (CryptoStream csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write))
{
using (StreamWriter swEncrypt = new StreamWriter(csEncrypt))
{
//Write all data to the stream.
swEncrypt.Write(plainText);
}
}
encrypted = msEncrypt.ToArray();
}
}
// Return the encrypted bytes from the memory stream.
return Convert.ToBase64String(encrypted);
}
public string Decrypt(string cipherText, string Key, string IV)
{
// Check arguments.
if (string.IsNullOrWhiteSpace(cipherText))
throw new ArgumentNullException(nameof(cipherText));
if (string.IsNullOrWhiteSpace(Key))
throw new ArgumentNullException(nameof(Key));
if (string.IsNullOrWhiteSpace(IV))
throw new ArgumentNullException(nameof(IV));
// Declare the string used to hold
// the decrypted text.
string plaintext = string.Empty;
// Create an AesCryptoServiceProvider object
// with the specified key and IV.
using (Aes aes = Aes.Create())
{
aes.Key = Convert.FromBase64String(Key);
aes.IV = Convert.FromBase64String(IV);
// Create a decrypt-or to perform the stream transform.
ICryptoTransform decryptor = aes.CreateDecryptor(aes.Key, aes.IV);
// Create the streams used for decryption.
using (MemoryStream msDecrypt = new MemoryStream(Convert.FromBase64String(cipherText)))
{
using (CryptoStream csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read))
{
using (StreamReader srDecrypt = new StreamReader(csDecrypt))
{
// Read the decrypted bytes from the decrypting stream
// and place them in a string.
plaintext = srDecrypt.ReadToEnd();
}
}
}
}
return plaintext;
}
public void Run()
{
Console.WriteLine("Key is : " + key);
Console.WriteLine("IV is : " + iv);
string passord = "s3cr3t";
string encryptedPassowrd = Encrypt(passord, key, iv);
string decryptedPassowrd = Decrypt(encryptedPassowrd, key, iv);
Console.WriteLine($"Password = {passord} and Encrypted password = {encryptedPassowrd}");
Console.WriteLine($"Password = {passord} and Decrypted password = {decryptedPassowrd}");
string passord1 = "s3cr4t";
string encryptedPassowrd1 = Encrypt(passord1, key, iv);
string decryptedPassowrd1 = Decrypt(encryptedPassowrd1, key, iv);
Console.WriteLine($"Password = {passord1} and Encrypted password = {encryptedPassowrd1}");
Console.WriteLine($"Password = {passord1} and Decrypted password = {decryptedPassowrd1}");
}
}

I think you misunderstood the example in the documentation of Rfc2898DeriveBytes. This function can be used for password hashing (PBKDF2), but then you don't need the encryption parts. The original use case of a key derivation function like PBKDF2 was to take a (weak) user password and turn it into a (strong) key which can then be used to encrypt data (thus the name key-derivation). Later one saw that the same functions are suitable to generate password hashes.
In your case I would recommend to use an appropriate library for password hashing, like BCrypt.Net. The usage would look like:
// Hash a new password for storing in the database.
// The function automatically generates a cryptographically safe salt.
string hashToStoreInDb = BCrypt.HashPassword(password);
// Check if the hash of the entered login password, matches the stored hash.
// The salt and the cost factor will be extracted from existingHashFromDb.
bool isPasswordCorrect = BCrypt.Verify(password, existingHashFromDb);

AES encryption in C# and nodejs

I have a C# encryption which is looking like that:
public static string EncryptAes(string value, string password, string iv)
{
var result = Encrypt<AesManaged>(value, password, iv);
return result;
}
static string Encrypt<T>(string value, string password, string salt)
where T : SymmetricAlgorithm, new()
{
DeriveBytes rgb = new Rfc2898DeriveBytes(password, Encoding.Unicode.GetBytes(salt));
SymmetricAlgorithm algorithm = new T();
byte[] rgbKey = rgb.GetBytes(algorithm.KeySize >> 3);
byte[] rgbIV = rgb.GetBytes(algorithm.BlockSize >> 3);
ICryptoTransform transform = algorithm.CreateEncryptor(rgbKey, rgbIV);
using (MemoryStream buffer = new MemoryStream())
{
using (CryptoStream stream = new CryptoStream(buffer, transform, CryptoStreamMode.Write))
{
using (StreamWriter writer = new StreamWriter(stream, Encoding.Unicode))
{
writer.Write(value);
}
}
return Convert.ToBase64String(buffer.ToArray());
}
}
The call to this function returns a string. Now I want to produce the same string in nodejs. I'm trying with npm crypto in the following manner:
function encrypt(text, password, iv) {
let cipher = crypto.createCipheriv('aes-256-cbc', password, iv);
var crypted = cipher.update(text,'utf8','base64')
crypted += cipher.final('base64');
return crypted;
}
The problem is that I can't produce the same strings.
The sole purpose of this is that I need to decrypt the c# encrypted data as shown above in nodejs. I can't change the encryption, but I can require any npm in node.

Password hashing in UWP

I have the following code in .net framework.
public string GetHashedPassword(string password, string salt)
{
byte[] saltArray = Convert.FromBase64String(salt);
byte[] passArray = Convert.FromBase64String(password);
byte[] salted = new byte[saltArray.Length + passArray.Length];
byte[] hashed = null;
saltArray.CopyTo(salted, 0);
passArray.CopyTo(salted, saltArray.Length);
using (var hash = new SHA256Managed())
{
hashed = hash.ComputeHash(salted);
}
return Convert.ToBase64String(hashed);
}
I'm trying to create an equivalent in .net core for a UWP application. Here's what I have so far.
public string GetHashedPassword(string password, string salt)
{
IBuffer input = CryptographicBuffer.ConvertStringToBinary(password + salt, BinaryStringEncoding.Utf8);
var hashAlgorithm = HashAlgorithmProvider.OpenAlgorithm(HashAlgorithmNames.Sha256);
var hash = hashAlgorithm.HashData(input);
//return CryptographicBuffer.ConvertBinaryToString(BinaryStringEncoding.Utf8, hash);
}
The last line, converting the buffer back to a string doesn't work. I get this exception:
No mapping for the Unicode character exists in the target multi-byte code page.
How can I convert the buffer back into a string?

I am assuming, that you want to get the hashed password in a base64-format, because you did that in your .net example.
To get this, change:
CryptographicBuffer.ConvertBinaryToString(BinaryStringEncoding.Utf8, hash);
to:
CryptographicBuffer.EncodeToBase64String(hash);
So the complete method looks like this:
public string GetHashedPassword(string password, string salt)
{
IBuffer input = CryptographicBuffer.ConvertStringToBinary(password + salt, BinaryStringEncoding.Utf8);
var hashAlgorithm = HashAlgorithmProvider.OpenAlgorithm(HashAlgorithmNames.Sha256);
var hash = hashAlgorithm.HashData(input);
return CryptographicBuffer.EncodeToBase64String(hash);
}

Rijndael initialization vector with 16 bytes

I have to credit card number to be encrypted and stored in database as a string. I do the following
RijndaelManaged rijMan = new RijndaelManaged();
byte[] encrypt = Encrypt(txtCredit.Text, rijMan.Key, rijMan.IV);
string card = Convert.ToBase64String(encrypt);
string key = Convert.ToBase64String(rijMan.Key);
string iv = Convert.ToBase64String(rijMan.IV);
and this is encrypt function:
public static byte[] Encrypt(string message, byte[] key, byte[] iv)
{
byte[] encrypted;
using (RijndaelManaged rijMan = new RijndaelManaged())
{
rijMan.Key = key;
rijMan.IV = iv;
ICryptoTransform encrypt = rijMan.CreateEncryptor(rijMan.Key, rijMan.IV);
using (MemoryStream ms = new MemoryStream())
{
using (CryptoStream cs = new CryptoStream(ms, encrypt, CryptoStreamMode.Write))
{
using (StreamWriter sw = new StreamWriter(cs))
{
sw.Write(message);
}
encrypted = ms.ToArray();
}
}
}
return encrypted;
}
And i store them all in database. This seems to be fine. But when i retrieve back the string from database and use System.Text.Encoding.UTF8.GetBytes(string) to convert to byte, it throws an exception
Specified initialization vector (IV) does not match the block size for this algorithm.
Is it possible to generate the IV such that it is 16 bytes ? Thanks in advance for the reply

In the top of your post you are using BASE64 algorithm to convert IV bytes to string
string ivString = Convert.ToBase64String(rijMan.IV);
and then in the bottom of your post you are using UTF8 encoding to read string into byte array
byte[] iv = System.Text.Encoding.UTF8.GetBytes(ivString);
but you should use BASE64 algorithm again:
byte[] iv = Convert.FromBase64String(ivString);
BTW: I hope you are not storing AES key (rijMan.Key) in the same database as your encrypted credit card number because that would make whole encryption completely useless.

How should I encrypt data to send in URL

I need to encrypt a string which I am sending in a URL and later I need to decrypt it ...
Which approach would be better for this? I tried the following:
string s = "String to be encrypted";
string encrypted = CipherUtility.Encrypt<RijndaelManaged>(s, "pass", "salt");
string decrypted = CipherUtility.Decrypt<RijndaelManaged>(encrypted, "pass", "salt");
But the encrypted string gets an "=" at the end ... I would like to avoid that.
And I am not sure that this would be the best option ...
The CipherUtility is the following:
public class CipherUtility
{
public static string Encrypt<T>(string value, string password, string salt)
where T : SymmetricAlgorithm, new()
{
DeriveBytes rgb = new Rfc2898DeriveBytes(password, Encoding.Unicode.GetBytes(salt));
SymmetricAlgorithm algorithm = new T();
byte[] rgbKey = rgb.GetBytes(algorithm.KeySize >> 3);
byte[] rgbIV = rgb.GetBytes(algorithm.BlockSize >> 3);
ICryptoTransform transform = algorithm.CreateEncryptor(rgbKey, rgbIV);
using (MemoryStream buffer = new MemoryStream())
{
using (CryptoStream stream = new CryptoStream(buffer, transform, CryptoStreamMode.Write))
{
using (StreamWriter writer = new StreamWriter(stream, Encoding.Unicode))
{
writer.Write(value);
}
}
return Convert.ToBase64String(buffer.ToArray());
}
}
public static string Decrypt<T>(string text, string password, string salt)
where T : SymmetricAlgorithm, new()
{
DeriveBytes rgb = new Rfc2898DeriveBytes(password, Encoding.Unicode.GetBytes(salt));
SymmetricAlgorithm algorithm = new T();
byte[] rgbKey = rgb.GetBytes(algorithm.KeySize >> 3);
byte[] rgbIV = rgb.GetBytes(algorithm.BlockSize >> 3);
ICryptoTransform transform = algorithm.CreateDecryptor(rgbKey, rgbIV);
using (MemoryStream buffer = new MemoryStream(Convert.FromBase64String(text)))
{
using (CryptoStream stream = new CryptoStream(buffer, transform, CryptoStreamMode.Read))
{
using (StreamReader reader = new StreamReader(stream, Encoding.Unicode))
{
return reader.ReadToEnd();
}
}
}
}
}
Thank You,
Miguel

On a newsletter I received I see something like /unsubscribe?u=16b832d9ad4b28edf261f56df. I was looking for something like this with the email somehow "hidden"
This is not "hidden." All this is a reference to a repository (e.g. a database) that contains all the information necessary to unsubscribe. Essentially a key into a record that contains all the necessary info about a subscriber.
If feasible, that'll probably be easier approach than to encrypt individual values in a URL.
If you still want to encrypt the value (to avoid storage in DB and redesign), what's the issue with having = at the end of a URL? It's just a character as part of encrypted output?