"Tool" naming was annoying me

NDecrypt.Core/DSProcessor.cs

@@ -0,0 +1,216 @@
+using System;
+using System.IO;
+using System.Text;
+using SabreTools.Hashing;
+using SabreTools.IO.Extensions;
+using SabreTools.Serialization.Wrappers;
+
+namespace NDecrypt.Core
+{
+    public class DSProcessor : ICartProcessor
+    {
+        #region Properties
+
+        /// <summary>
+        /// Blowfish Table
+        /// </summary>
+        public byte[] BlowfishTable
+        {
+            get;
+            set
+            {
+                // Ignore missing encryption data
+                if (value.Length == 0)
+                    return;
+
+                // Validate the blowfish table data
+                byte[]? actual = HashTool.GetByteArrayHashArray(value, HashType.SHA512);
+                if (actual is null || !actual.EqualsExactly(ExpectedNitroSha512Hash))
+                    return;
+
+                // Assign the validated value
+                field = value;
+            }
+        } = [];
+
+        #endregion
+
+        #region Internal Test Values
+
+        /// <summary>
+        /// Expected hash for NitroEncryptionData
+        /// </summary>
+        private static readonly byte[] ExpectedNitroSha512Hash =
+        [
+            0x1A, 0xD6, 0x40, 0x21, 0xFC, 0x3D, 0x1A, 0x9A,
+            0x9B, 0xC0, 0x88, 0x8E, 0x2E, 0x68, 0xDE, 0x4E,
+            0x8A, 0x60, 0x6B, 0x86, 0x63, 0x22, 0xD2, 0xC7,
+            0xC6, 0xD7, 0xD6, 0xCE, 0x65, 0xF5, 0xBA, 0xA7,
+            0xEA, 0x69, 0x63, 0x7E, 0xC9, 0xE4, 0x57, 0x7B,
+            0x01, 0xFD, 0xCE, 0xC2, 0x26, 0x3B, 0xD9, 0x0D,
+            0x84, 0x57, 0xC2, 0x00, 0xB8, 0x56, 0x9F, 0xE5,
+            0x56, 0xDA, 0x8D, 0xDE, 0x84, 0xB8, 0x8E, 0xE4,
+        ];
+
+        #endregion
+
+        #region Encrypt
+
+        /// <inheritdoc/>
+        public bool EncryptFile(string input, string? output, bool force)
+        {
+            // If the blowfish table is not set, do not process
+            if (BlowfishTable.Length == 0)
+            {
+                Console.WriteLine("Error: Nitro encryption data not provided!");
+                return false;
+            }
+
+            try
+            {
+                // If the output is provided, copy the input file
+                if (output is not null)
+                    File.Copy(input, output, overwrite: true);
+                else
+                    output = input;
+
+                // Open the output file for processing
+                using var reader = File.Open(output, FileMode.Open, FileAccess.Read, FileShare.ReadWrite);
+
+                // Deserialize the cart information
+                var nitro = Nitro.Create(reader);
+                if (nitro is null)
+                {
+                    Console.WriteLine("Error: Not a DS or DSi Rom!");
+                    return false;
+                }
+
+                // Ensure the secure area was read
+                if (nitro.SecureArea is null)
+                {
+                    Console.WriteLine("Error: Invalid secure area!");
+                    return false;
+                }
+
+                // Encrypt the secure area
+                nitro.EncryptSecureArea(BlowfishTable, force);
+
+                // Write the encrypted secure area
+                using var writer = File.Open(output, FileMode.Open, FileAccess.ReadWrite, FileShare.ReadWrite);
+                writer.Seek(0x4000, SeekOrigin.Begin);
+                writer.Write(nitro.SecureArea);
+                writer.Flush();
+
+                return true;
+            }
+            catch
+            {
+                Console.WriteLine($"An error has occurred. {output} may be corrupted if it was partially processed.");
+                Console.WriteLine("Please check that the file was a valid DS or DSi file and try again.");
+                return false;
+            }
+        }
+
+        #endregion
+
+        #region Decrypt
+
+        /// <inheritdoc/>
+        public bool DecryptFile(string input, string? output, bool force)
+        {
+            // If the blowfish table is not set, do not process
+            if (BlowfishTable.Length == 0)
+            {
+                Console.WriteLine("Error: Nitro encryption data not provided!");
+                return false;
+            }
+
+            try
+            {
+                // If the output is provided, copy the input file
+                if (output is not null)
+                    File.Copy(input, output, overwrite: true);
+                else
+                    output = input;
+
+                // Open the read and write on the same file for inplace processing
+                using var reader = File.Open(output, FileMode.Open, FileAccess.Read, FileShare.ReadWrite);
+
+                // Deserialize the cart information
+                var nitro = Nitro.Create(reader);
+                if (nitro is null)
+                {
+                    Console.WriteLine("Error: Not a DS or DSi Rom!");
+                    return false;
+                }
+
+                // Ensure the secure area was read
+                if (nitro.SecureArea is null)
+                {
+                    Console.WriteLine("Error: Invalid secure area!");
+                    return false;
+                }
+
+                // Decrypt the secure area
+                nitro.DecryptSecureArea(BlowfishTable, force);
+
+                // Write the decrypted secure area
+                using var writer = File.Open(output, FileMode.Open, FileAccess.ReadWrite, FileShare.ReadWrite);
+                writer.Seek(0x4000, SeekOrigin.Begin);
+                writer.Write(nitro.SecureArea);
+                writer.Flush();
+
+                return true;
+            }
+            catch
+            {
+                Console.WriteLine($"An error has occurred. {output} may be corrupted if it was partially processed.");
+                Console.WriteLine("Please check that the file was a valid DS or DSi file and try again.");
+                return false;
+            }
+        }
+
+        #endregion
+
+        #region Info
+
+        /// <inheritdoc/>
+        public string? GetInformation(string filename)
+        {
+            try
+            {
+                // Open the file for reading
+                using var input = File.Open(filename, FileMode.Open, FileAccess.Read, FileShare.ReadWrite);
+
+                // Deserialize the cart information
+                var cart = Nitro.Create(input);
+                if (cart?.Model is null)
+                    return "Error: Not a DS/DSi cart image!";
+
+                // Get a string builder for the status
+                var sb = new StringBuilder();
+                sb.Append("\tSecure Area: ");
+
+                // Get the encryption status
+                bool? decrypted = cart.CheckIfDecrypted(out _);
+                if (decrypted is null)
+                    sb.Append("Empty");
+                else if (decrypted == true)
+                    sb.Append("Decrypted");
+                else
+                    sb.Append("Encrypted");
+
+                // Return the status for the secure area
+                sb.Append(Environment.NewLine);
+                return sb.ToString();
+            }
+            catch (Exception ex)
+            {
+                Console.WriteLine(ex);
+                return null;
+            }
+        }
+
+        #endregion
+    }
+}