Aaru/Aaru.Filesystems/ReFS.cs

// /***************************************************************************
// Aaru Data Preservation Suite
// ----------------------------------------------------------------------------
//
// Filename       : ReFS.cs
// Author(s)      : Natalia Portillo <claunia@claunia.com>
//
// Component      : Resilient File System plugin
//
// --[ Description ] ----------------------------------------------------------
//
//     Identifies the Resilient File System and shows information.
//
// --[ License ] --------------------------------------------------------------
//
//     This library is free software; you can redistribute it and/or modify
//     it under the terms of the GNU Lesser General Public License as
//     published by the Free Software Foundation; either version 2.1 of the
//     License, or (at your option) any later version.
//
//     This library is distributed in the hope that it will be useful, but
//     WITHOUT ANY WARRANTY; without even the implied warranty of
//     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
//     Lesser General Public License for more details.
//
//     You should have received a copy of the GNU Lesser General Public
//     License along with this library; if not, see <http://www.gnu.org/licenses/>.
//
// ----------------------------------------------------------------------------
// Copyright © 2011-2022 Natalia Portillo
// ****************************************************************************/

using System;
using System.Linq;
using System.Runtime.InteropServices;
using System.Text;
using Aaru.CommonTypes;
using Aaru.CommonTypes.Enums;
using Aaru.CommonTypes.Interfaces;
using Aaru.Console;
using Aaru.Helpers;
using Schemas;
using Marshal = Aaru.Helpers.Marshal;

namespace Aaru.Filesystems;

/// <inheritdoc />
/// <summary>Implements detection of Microsoft's Resilient filesystem (ReFS)</summary>
public sealed class ReFS : IFilesystem
{
    const uint FSRS = 0x53525346;
    readonly byte[] _signature =
    {
        0x52, 0x65, 0x46, 0x53, 0x00, 0x00, 0x00, 0x00
    };
    /// <inheritdoc />
    public string Name => "Resilient File System plugin";
    /// <inheritdoc />
    public Guid Id => new("37766C4E-EBF5-4113-A712-B758B756ABD6");
    /// <inheritdoc />
    public FileSystemType XmlFsType { get; private set; }
    /// <inheritdoc />
    public Encoding Encoding { get; private set; }
    /// <inheritdoc />
    public string Author => "Natalia Portillo";

    /// <inheritdoc />
    public bool Identify(IMediaImage imagePlugin, Partition partition)
    {
        uint sbSize = (uint)(Marshal.SizeOf<VolumeHeader>() / imagePlugin.Info.SectorSize);

        if(Marshal.SizeOf<VolumeHeader>() % imagePlugin.Info.SectorSize != 0)
            sbSize++;

        if(partition.Start + sbSize >= partition.End)
            return false;

        ErrorNumber errno = imagePlugin.ReadSectors(partition.Start, sbSize, out byte[] sector);

        if(errno != ErrorNumber.NoError)
            return false;

        if(sector.Length < Marshal.SizeOf<VolumeHeader>())
            return false;

        VolumeHeader vhdr = Marshal.ByteArrayToStructureLittleEndian<VolumeHeader>(sector);

        return vhdr.identifier == FSRS && ArrayHelpers.ArrayIsNullOrEmpty(vhdr.mustBeZero) &&
               vhdr.signature.SequenceEqual(_signature);
    }

    /// <inheritdoc />
    public void GetInformation(IMediaImage imagePlugin, Partition partition, out string information, Encoding encoding)
    {
        Encoding    = Encoding.UTF8;
        information = "";

        uint sbSize = (uint)(Marshal.SizeOf<VolumeHeader>() / imagePlugin.Info.SectorSize);

        if(Marshal.SizeOf<VolumeHeader>() % imagePlugin.Info.SectorSize != 0)
            sbSize++;

        if(partition.Start + sbSize >= partition.End)
            return;

        ErrorNumber errno = imagePlugin.ReadSectors(partition.Start, sbSize, out byte[] sector);

        if(errno != ErrorNumber.NoError)
            return;

        if(sector.Length < Marshal.SizeOf<VolumeHeader>())
            return;

        VolumeHeader vhdr = Marshal.ByteArrayToStructureLittleEndian<VolumeHeader>(sector);

        AaruConsole.DebugWriteLine("ReFS plugin", "VolumeHeader.jump empty? = {0}",
                                   ArrayHelpers.ArrayIsNullOrEmpty(vhdr.jump));

        AaruConsole.DebugWriteLine("ReFS plugin", "VolumeHeader.signature = {0}",
                                   StringHandlers.CToString(vhdr.signature));

        AaruConsole.DebugWriteLine("ReFS plugin", "VolumeHeader.mustBeZero empty? = {0}",
                                   ArrayHelpers.ArrayIsNullOrEmpty(vhdr.mustBeZero));

        AaruConsole.DebugWriteLine("ReFS plugin", "VolumeHeader.identifier = {0}",
                                   StringHandlers.CToString(BitConverter.GetBytes(vhdr.identifier)));

        AaruConsole.DebugWriteLine("ReFS plugin", "VolumeHeader.length = {0}", vhdr.length);
        AaruConsole.DebugWriteLine("ReFS plugin", "VolumeHeader.checksum = 0x{0:X4}", vhdr.checksum);
        AaruConsole.DebugWriteLine("ReFS plugin", "VolumeHeader.sectors = {0}", vhdr.sectors);
        AaruConsole.DebugWriteLine("ReFS plugin", "VolumeHeader.bytesPerSector = {0}", vhdr.bytesPerSector);

        AaruConsole.DebugWriteLine("ReFS plugin", "VolumeHeader.sectorsPerCluster = {0}", vhdr.sectorsPerCluster);

        AaruConsole.DebugWriteLine("ReFS plugin", "VolumeHeader.unknown1 zero? = {0}", vhdr.unknown1 == 0);
        AaruConsole.DebugWriteLine("ReFS plugin", "VolumeHeader.unknown2 zero? = {0}", vhdr.unknown2 == 0);
        AaruConsole.DebugWriteLine("ReFS plugin", "VolumeHeader.unknown3 zero? = {0}", vhdr.unknown3 == 0);
        AaruConsole.DebugWriteLine("ReFS plugin", "VolumeHeader.unknown4 zero? = {0}", vhdr.unknown4 == 0);

        AaruConsole.DebugWriteLine("ReFS plugin", "VolumeHeader.unknown5 empty? = {0}",
                                   ArrayHelpers.ArrayIsNullOrEmpty(vhdr.unknown5));

        if(vhdr.identifier != FSRS                           ||
           !ArrayHelpers.ArrayIsNullOrEmpty(vhdr.mustBeZero) ||
           !vhdr.signature.SequenceEqual(_signature))
            return;

        var sb = new StringBuilder();

        sb.AppendLine("Microsoft Resilient File System");
        sb.AppendFormat("Volume uses {0} bytes per sector", vhdr.bytesPerSector).AppendLine();

        sb.AppendFormat("Volume uses {0} sectors per cluster ({1} bytes)", vhdr.sectorsPerCluster,
                        vhdr.sectorsPerCluster * vhdr.bytesPerSector).AppendLine();

        sb.AppendFormat("Volume has {0} sectors ({1} bytes)", vhdr.sectors, vhdr.sectors * vhdr.bytesPerSector).
           AppendLine();

        information = sb.ToString();

        XmlFsType = new FileSystemType
        {
            Type        = "Resilient File System",
            ClusterSize = vhdr.bytesPerSector * vhdr.sectorsPerCluster,
            Clusters    = vhdr.sectors        / vhdr.sectorsPerCluster
        };
    }

    [StructLayout(LayoutKind.Sequential, Pack = 1)]
    readonly struct VolumeHeader
    {
        [MarshalAs(UnmanagedType.ByValArray, SizeConst = 3)]
        public readonly byte[] jump;
        [MarshalAs(UnmanagedType.ByValArray, SizeConst = 8)]
        public readonly byte[] signature;
        [MarshalAs(UnmanagedType.ByValArray, SizeConst = 5)]
        public readonly byte[] mustBeZero;
        public readonly uint   identifier;
        public readonly ushort length;
        public readonly ushort checksum;
        public readonly ulong  sectors;
        public readonly uint   bytesPerSector;
        public readonly uint   sectorsPerCluster;
        public readonly uint   unknown1;
        public readonly uint   unknown2;
        public readonly ulong  unknown3;
        public readonly ulong  unknown4;
        [MarshalAs(UnmanagedType.ByValArray, SizeConst = 15872)]
        public readonly byte[] unknown5;
    }
}