Add raw DVD reading with HL-DT-ST command (#823)

Aaru.Devices/Device/ScsiCommands/HL-DT-ST.cs

@@ -30,12 +30,19 @@
 // Copyright © 2011-2023 Natalia Portillo
 // ****************************************************************************/
 
+using System;
+using System.Collections.Generic;
+using Aaru.CommonTypes.Enums;
 using Aaru.Console;
+using Aaru.Decoders.DVD;
+using Aaru.Helpers;
 
 namespace Aaru.Devices;
 
 public partial class Device
 {
+    readonly Sector _decoding = new();
+
     /// <summary>Reads a "raw" sector from DVD on HL-DT-ST drives.</summary>
     /// <returns><c>true</c> if the command failed and <paramref name="senseBuffer" /> contains the sense buffer.</returns>
     /// <param name="buffer">Buffer where the HL-DT-ST READ DVD (RAW) response will be stored</param>
@@ -51,15 +58,17 @@ public partial class Device
         var cdb = new byte[12];
         buffer = new byte[2064 * transferLength];
 
+        uint cacheDataOffset = 0x80000000 + (lba % 96 * 2064);
+
         cdb[0]  = (byte)ScsiCommands.HlDtStVendor;
         cdb[1]  = 0x48;
         cdb[2]  = 0x49;
         cdb[3]  = 0x54;
         cdb[4]  = 0x01;
-        cdb[6]  = (byte)((lba & 0xFF000000) >> 24);
-        cdb[7]  = (byte)((lba & 0xFF0000)   >> 16);
-        cdb[8]  = (byte)((lba & 0xFF00)     >> 8);
-        cdb[9]  = (byte)(lba & 0xFF);
+        cdb[6]  = (byte)((cacheDataOffset & 0xFF000000) >> 24);
+        cdb[7]  = (byte)((cacheDataOffset & 0xFF0000)   >> 16);
+        cdb[8]  = (byte)((cacheDataOffset & 0xFF00)     >> 8);
+        cdb[9]  = (byte)(cacheDataOffset & 0xFF);
         cdb[10] = (byte)((buffer.Length & 0xFF00) >> 8);
         cdb[11] = (byte)(buffer.Length & 0xFF);
 
@@ -70,6 +79,38 @@ public partial class Device
 
         AaruConsole.DebugWriteLine(SCSI_MODULE_NAME, Localization.HL_DT_ST_READ_DVD_RAW_took_0_ms, duration);
 
+        if(!CheckSectorNumber(buffer, lba, transferLength))
+            return true;
+
+        if(_decoding.Scramble(buffer, transferLength, out byte[] scrambledBuffer) != ErrorNumber.NoError)
+            return true;
+
+        buffer = scrambledBuffer;
         return sense;
     }
+
+    /// <summary>
+    /// Makes sure the data's sector number is the one expected.
+    /// </summary>
+    /// <param name="buffer">Data buffer</param>
+    /// <param name="firstLba">First consecutive LBA of the buffer</param>
+    /// <param name="transferLength">How many blocks to in buffer</param>
+    /// <returns><c>false</c> if any sector is not matching expected value, else <c>true</c></returns>
+    static bool CheckSectorNumber(IReadOnlyList<byte> buffer, uint firstLba, uint transferLength)
+    {
+        for(int i = 0; i < transferLength; i++)
+        {
+            byte[] sectorBuffer =
+            {
+                0x0, buffer[1 + (2064 * i)], buffer[2 + (2064 * i)], buffer[3 + (2064 * i)]
+            };
+
+            uint sectorNumber = BigEndianBitConverter.ToUInt32(sectorBuffer, 0);
+
+            if(sectorNumber != firstLba + i + 0x30000)
+                return false;
+        }
+
+        return true;
+    }
 }