HGdBBBA6

1using System;
2using System.Collections.Generic;
3using System.Linq;
4using System.Text;
5using System.Threading.Tasks;
6using System.Security.Cryptography;
7using System.IO;
8
9namespace Common
10{
11    public class Encryption
12    {
13        //Admin password Test123
14        public string HashString(string mytext)
15        {
16            SHA256 myAlg = SHA256.Create();//initialize the algorithm instance
17
18            byte[] input = Encoding.UTF32.GetBytes(mytext); //converting from string to byte[]
19            byte[] digest = myAlg.ComputeHash(input); //converting from string to byte[]
20
21            return Convert.ToBase64String(digest); //converting back from byte[] to string
22        }
23
24        public SymetricParamaters GenerateSymmetricParamaters(string input)
25        {
26            Rfc2898DeriveBytes rfc = new Rfc2898DeriveBytes(input, new byte[] { 20, 255, 1, 60, 54, 78, 52, 30 });
27
28            Rijndael myAlg = Rijndael.Create();
29
30            SymetricParamaters myParams = new SymetricParamaters()
31            {
32                SecretKey = rfc.GetBytes(myAlg.KeySize / 8),
33                IV = rfc.GetBytes(myAlg.BlockSize / 8)
34            };
35
36            return myParams;
37        }
38
39        //Still needs to be implemented in Index.cshtml
40        public string EncryptString(string input, string passwordToBeUsedInSecretKey)
41        {
42            SymetricParamaters myParameters = GenerateSymmetricParamaters(passwordToBeUsedInSecretKey);
43
44            Rijndael myAlg = Rijndael.Create();
45            myAlg.Key = myParameters.SecretKey;
46            myAlg.IV = myParameters.IV;
47
48            byte[] clearDataAsBytes = Encoding.UTF32.GetBytes(input);
49
50            MemoryStream msClearData = new MemoryStream(clearDataAsBytes);
51            CryptoStream cs = new CryptoStream(msClearData, myAlg.CreateEncryptor(), CryptoStreamMode.Read);
52
53            MemoryStream msEncrypteData = new MemoryStream();
54            cs.CopyTo(msEncrypteData);
55
56            byte[] encrypteDataAsBytes = msEncrypteData.ToArray();
57            string encrypteddata = Convert.ToBase64String(encrypteDataAsBytes); //converting to string the cryptographic data
58
59            encrypteddata = encrypteddata.Replace('=', '|');
60            encrypteddata = encrypteddata.Replace('/', '_');
61            encrypteddata = encrypteddata.Replace('+', '*');
62
63            return encrypteddata;
64        }
65
66        public string DecryptString(string input, string passwordToBeUsedInSecretKey)
67        {
68
69            input = input.Replace('|', '=');
70            input = input.Replace('_', '/');
71            input = input.Replace('*', '+');
72
73            //Need to change below
74            SymetricParamaters myParameters = GenerateSymmetricParamaters(passwordToBeUsedInSecretKey);
75
76            Rijndael myAlg = Rijndael.Create();
77            myAlg.Key = myParameters.SecretKey;
78            myAlg.IV = myParameters.IV;
79
80            byte[] encryptedDataAsBytes = Convert.FromBase64String(input); //Make decoding;
81
82            MemoryStream msEncryptedData = new MemoryStream(encryptedDataAsBytes);
83            CryptoStream cs = new CryptoStream(msEncryptedData, myAlg.CreateDecryptor(), CryptoStreamMode.Read);
84
85            MemoryStream msClearData = new MemoryStream();
86            cs.CopyTo(msClearData);
87
88            byte[] clearDataAsBytes = msClearData.ToArray();
89            string clearData = Encoding.UTF32.GetString(clearDataAsBytes); //converting to string the cryptographic data
90
91            return clearData;
92        }
93    }
94
95    public class SymetricParamaters
96    {
97        public byte[] SecretKey { get; set; }
98        public byte[] IV { get; set; }
99
100    }
101}