Initial commit: JDE Scoping Tool migration project

Set up repository with legacy .NET Framework 4.8 source (OLD/),
new .NET 10 Blazor solution (NEW/), OpenSpec specifications,
documentation, and project configuration.

OLD/DataModel/Helpers/EncryptionHelper.cs

@@ -0,0 +1,141 @@
+using System;
+using System.IO;
+using System.Security.Cryptography;
+using System.Text;
+
+namespace DataModel.Helpers
+{
+    /// <summary>
+    /// Helper methods for encryption / decryption
+    /// </summary>
+    public class EncryptionHelper
+    {
+        /// <summary>
+        /// Default salt value
+        /// </summary>
+        private const string DEFAULT_SALT = ")kjdnl3k1jh234a9";
+
+        /// <summary>
+        /// Default hashing algorithm to use
+        /// </summary>
+        private const string DEFAULT_HASH_ALGORITHM = "SHA1";
+
+        /// <summary>
+        /// Default number of iterations to do
+        /// </summary>
+        private const int DEFAULT_PASSWORD_ITERATION = 2;
+
+        /// <summary>
+        /// Default initialization vector
+        /// </summary>
+        private const string DEFAULT_INITIAL_VECTOR = "X8pgVu239uOjdKH1";
+
+        /// <summary>
+        /// Default encryption keysize
+        /// </summary>
+        private const int DEFAULT_KEYSIZE = 256;
+
+        /// <summary>
+        /// Encrypts a string
+        /// </summary>
+        /// <param name="plainText">Text to be encrypted</param>
+        /// <param name="password">Password to encrypt with</param>
+        /// <param name="salt">Salt to encrypt with</param>
+        /// <param name="hashAlgorithm">Can be either SHA1 or MD5</param>
+        /// <param name="passwordIterations">Number of iterations to do</param>
+        /// <param name="initialVector">Needs to be 16 ASCII characters long</param>
+        /// <param name="keySize">Can be 128, 192, or 256</param>
+        /// <returns>An encrypted string</returns>
+        public static string Encrypt(string plainText, string password, string salt = DEFAULT_SALT, string hashAlgorithm = DEFAULT_HASH_ALGORITHM, int passwordIterations = DEFAULT_PASSWORD_ITERATION, string initialVector = DEFAULT_INITIAL_VECTOR, int keySize = DEFAULT_KEYSIZE)
+        {
+            if (string.IsNullOrEmpty(plainText))
+            {
+                return "";
+            }
+
+            byte[] initialVectorBytes = Encoding.ASCII.GetBytes(initialVector);
+            byte[] saltValueBytes = Encoding.ASCII.GetBytes(salt);
+            byte[] plainTextBytes = Encoding.UTF8.GetBytes(plainText);
+
+            PasswordDeriveBytes derivedPassword = new PasswordDeriveBytes(password, saltValueBytes, hashAlgorithm, passwordIterations);
+            byte[] keyBytes = derivedPassword.GetBytes(keySize / 8);
+
+            RijndaelManaged symmetricKey = new RijndaelManaged
+            {
+                Mode = CipherMode.CBC
+            };
+            byte[] cipherTextBytes = null;
+
+            using (ICryptoTransform encryptor = symmetricKey.CreateEncryptor(keyBytes, initialVectorBytes))
+            {
+                using (MemoryStream memStream = new MemoryStream())
+                {
+                    using (CryptoStream cryptoStream = new CryptoStream(memStream, encryptor, CryptoStreamMode.Write))
+                    {
+                        cryptoStream.Write(plainTextBytes, 0, plainTextBytes.Length);
+                        cryptoStream.FlushFinalBlock();
+                        cipherTextBytes = memStream.ToArray();
+                        memStream.Close();
+                        cryptoStream.Close();
+                    }
+                }
+            }
+
+            symmetricKey.Clear();
+
+            return Convert.ToBase64String(cipherTextBytes);
+        }
+
+        /// <summary>
+        /// Decrypts a string
+        /// </summary>
+        /// <param name="encrypted">Text to be decrypted</param>
+        /// <param name="password">Password to decrypt with</param>
+        /// <param name="salt">Salt to decrypt with</param>
+        /// <param name="hashAlgorithm">Can be either SHA1 or MD5</param>
+        /// <param name="passwordIterations">Number of iterations to do</param>
+        /// <param name="initialVector">Needs to be 16 ASCII characters long</param>
+        /// <param name="keySize">Can be 128, 192, or 256</param>
+        /// <returns>A decrypted string</returns>
+        public static string Decrypt(string encrypted, string password, string salt = DEFAULT_SALT, string hashAlgorithm = DEFAULT_HASH_ALGORITHM, int passwordIterations = DEFAULT_PASSWORD_ITERATION, string initialVector = DEFAULT_INITIAL_VECTOR, int keySize = DEFAULT_KEYSIZE)
+        {
+            if (string.IsNullOrEmpty(encrypted))
+            {
+                return "";
+            }
+
+            byte[] initialVectorBytes = Encoding.ASCII.GetBytes(initialVector);
+            byte[] saltValueBytes = Encoding.ASCII.GetBytes(salt);
+            byte[] cipherTextBytes = Convert.FromBase64String(encrypted);
+
+            PasswordDeriveBytes derivedPassword = new PasswordDeriveBytes(password, saltValueBytes, hashAlgorithm, passwordIterations);
+            byte[] keyBytes = derivedPassword.GetBytes(keySize / 8);
+
+            RijndaelManaged symmetricKey = new RijndaelManaged
+            {
+                Mode = CipherMode.CBC
+            };
+
+            byte[] plainTextBytes = new byte[cipherTextBytes.Length];
+            int byteCount = 0;
+
+            using (ICryptoTransform decrypt = symmetricKey.CreateDecryptor(keyBytes, initialVectorBytes))
+            {
+                using (MemoryStream memStream = new MemoryStream(cipherTextBytes))
+                {
+                    using (CryptoStream cryptoStream = new CryptoStream(memStream, decrypt, CryptoStreamMode.Read))
+                    {
+
+                        byteCount = cryptoStream.Read(plainTextBytes, 0, plainTextBytes.Length);
+                        memStream.Close();
+                        cryptoStream.Close();
+                    }
+                }
+            }
+
+            symmetricKey.Clear();
+
+            return Encoding.UTF8.GetString(plainTextBytes, 0, byteCount);
+        }
+    }
+}