Aaru/Aaru.Filesystems/AppleHFS/Info.cs

// /***************************************************************************
// Aaru Data Preservation Suite
// ----------------------------------------------------------------------------
//
// Filename       : Info.cs
// Author(s)      : Natalia Portillo <claunia@claunia.com>
//
// Component      : Apple Hierarchical File System plugin.
//
// --[ Description ] ----------------------------------------------------------
//
//     Identifies the Apple Hierarchical 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.Text;
using Aaru.CommonTypes;
using Aaru.CommonTypes.Enums;
using Aaru.CommonTypes.Interfaces;
using Aaru.Helpers;
using Schemas;

namespace Aaru.Filesystems;

// Information from Inside Macintosh
// https://developer.apple.com/legacy/library/documentation/mac/pdf/Files/File_Manager.pdf
public sealed partial class AppleHFS
{
    /// <inheritdoc />
    public bool Identify(IMediaImage imagePlugin, Partition partition)
    {
        if(2 + partition.Start >= partition.End)
            return false;

        byte[]      mdbSector;
        ushort      drSigWord;
        ErrorNumber errno;

        if(imagePlugin.Info.SectorSize is 2352 or 2448 or 2048)
        {
            errno = imagePlugin.ReadSectors(partition.Start, 2, out mdbSector);

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

            foreach(int offset in new[]
                    {
                        0, 0x200, 0x400, 0x600, 0x800, 0xA00
                    }.Where(offset => mdbSector.Length >= offset + 0x7C + 2))
            {
                drSigWord = BigEndianBitConverter.ToUInt16(mdbSector, offset);

                if(drSigWord != AppleCommon.HFS_MAGIC)
                    continue;

                drSigWord = BigEndianBitConverter.ToUInt16(mdbSector, offset + 0x7C); // Seek to embedded HFS+ signature

                return drSigWord != AppleCommon.HFSP_MAGIC;
            }
        }
        else
        {
            errno = imagePlugin.ReadSector(2 + partition.Start, out mdbSector);

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

            if(mdbSector.Length < 0x7C + 2)
                return false;

            drSigWord = BigEndianBitConverter.ToUInt16(mdbSector, 0);

            if(drSigWord != AppleCommon.HFS_MAGIC)
                return false;

            drSigWord = BigEndianBitConverter.ToUInt16(mdbSector, 0x7C); // Seek to embedded HFS+ signature

            return drSigWord != AppleCommon.HFSP_MAGIC;
        }

        return false;
    }

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

        var sb = new StringBuilder();

        byte[]      bbSector  = null;
        byte[]      mdbSector = null;
        ushort      drSigWord;
        ErrorNumber errno;

        bool apmFromHddOnCd = false;

        if(imagePlugin.Info.SectorSize is 2352 or 2448 or 2048)
        {
            errno = imagePlugin.ReadSectors(partition.Start, 2, out byte[] tmpSector);

            if(errno != ErrorNumber.NoError)
                return;

            foreach(int offset in new[]
                    {
                        0, 0x200, 0x400, 0x600, 0x800, 0xA00
                    })
            {
                drSigWord = BigEndianBitConverter.ToUInt16(tmpSector, offset);

                if(drSigWord != AppleCommon.HFS_MAGIC)
                    continue;

                bbSector  = new byte[1024];
                mdbSector = new byte[512];

                if(offset >= 0x400)
                    Array.Copy(tmpSector, offset - 0x400, bbSector, 0, 1024);

                Array.Copy(tmpSector, offset, mdbSector, 0, 512);
                apmFromHddOnCd = true;

                break;
            }

            if(!apmFromHddOnCd)
                return;
        }
        else
        {
            errno = imagePlugin.ReadSector(2 + partition.Start, out mdbSector);

            if(errno != ErrorNumber.NoError)
                return;

            drSigWord = BigEndianBitConverter.ToUInt16(mdbSector, 0);

            if(drSigWord == AppleCommon.HFS_MAGIC)
            {
                errno = imagePlugin.ReadSector(partition.Start, out bbSector);

                if(errno != ErrorNumber.NoError)
                    return;
            }
            else
                return;
        }

        MasterDirectoryBlock mdb = Marshal.ByteArrayToStructureBigEndian<MasterDirectoryBlock>(mdbSector);

        sb.AppendLine("Apple Hierarchical File System");
        sb.AppendLine();

        if(apmFromHddOnCd)
            sb.AppendLine("HFS uses 512 bytes/sector while device uses 2048 bytes/sector.").AppendLine();

        sb.AppendLine("Master Directory Block:");
        sb.AppendFormat("Creation date: {0}", DateHandlers.MacToDateTime(mdb.drCrDate)).AppendLine();
        sb.AppendFormat("Last modification date: {0}", DateHandlers.MacToDateTime(mdb.drLsMod)).AppendLine();

        if(mdb.drVolBkUp > 0)
        {
            sb.AppendFormat("Last backup date: {0}", DateHandlers.MacToDateTime(mdb.drVolBkUp)).AppendLine();
            sb.AppendFormat("Backup sequence number: {0}", mdb.drVSeqNum).AppendLine();
        }
        else
            sb.AppendLine("Volume has never been backed up");

        if(mdb.drAtrb.HasFlag(AppleCommon.VolumeAttributes.HardwareLock))
            sb.AppendLine("Volume is locked by hardware.");

        sb.AppendLine(mdb.drAtrb.HasFlag(AppleCommon.VolumeAttributes.Unmounted) ? "Volume was unmonted."
                          : "Volume is mounted.");

        if(mdb.drAtrb.HasFlag(AppleCommon.VolumeAttributes.SparedBadBlocks))
            sb.AppendLine("Volume has spared bad blocks.");

        if(mdb.drAtrb.HasFlag(AppleCommon.VolumeAttributes.DoesNotNeedCache))
            sb.AppendLine("Volume does not need cache.");

        if(mdb.drAtrb.HasFlag(AppleCommon.VolumeAttributes.BootInconsistent))
            sb.AppendLine("Boot volume is inconsistent.");

        if(mdb.drAtrb.HasFlag(AppleCommon.VolumeAttributes.ReusedIds))
            sb.AppendLine("There are reused CNIDs.");

        if(mdb.drAtrb.HasFlag(AppleCommon.VolumeAttributes.Journaled))
            sb.AppendLine("Volume is journaled.");

        if(mdb.drAtrb.HasFlag(AppleCommon.VolumeAttributes.Inconsistent))
            sb.AppendLine("Volume is seriously inconsistent.");

        if(mdb.drAtrb.HasFlag(AppleCommon.VolumeAttributes.SoftwareLock))
            sb.AppendLine("Volume is locked by software.");

        sb.AppendFormat("{0} files on root directory", mdb.drNmFls).AppendLine();
        sb.AppendFormat("{0} directories on root directory", mdb.drNmRtDirs).AppendLine();
        sb.AppendFormat("{0} files on volume", mdb.drFilCnt).AppendLine();
        sb.AppendFormat("{0} directories on volume", mdb.drDirCnt).AppendLine();
        sb.AppendFormat("Volume write count: {0}", mdb.drWrCnt).AppendLine();

        sb.AppendFormat("Volume bitmap starting sector (in 512-bytes): {0}", mdb.drVBMSt).AppendLine();
        sb.AppendFormat("Next allocation block: {0}.", mdb.drAllocPtr).AppendLine();
        sb.AppendFormat("{0} volume allocation blocks.", mdb.drNmAlBlks).AppendLine();
        sb.AppendFormat("{0} bytes per allocation block.", mdb.drAlBlkSiz).AppendLine();
        sb.AppendFormat("{0} bytes to allocate when extending a file.", mdb.drClpSiz).AppendLine();
        sb.AppendFormat("{0} bytes to allocate when extending a Extents B-Tree.", mdb.drXTClpSiz).AppendLine();
        sb.AppendFormat("{0} bytes to allocate when extending a Catalog B-Tree.", mdb.drCTClpSiz).AppendLine();
        sb.AppendFormat("Sector of first allocation block: {0}", mdb.drAlBlSt).AppendLine();
        sb.AppendFormat("Next unused CNID: {0}", mdb.drNxtCNID).AppendLine();
        sb.AppendFormat("{0} unused allocation blocks.", mdb.drFreeBks).AppendLine();

        sb.AppendFormat("{0} bytes in the Extents B-Tree", mdb.drXTFlSize).AppendLine();
        sb.AppendFormat("{0} bytes in the Catalog B-Tree", mdb.drCTFlSize).AppendLine();

        sb.AppendFormat("Volume name: {0}", StringHandlers.PascalToString(mdb.drVN, Encoding)).AppendLine();

        sb.AppendLine("Finder info:");
        sb.AppendFormat("CNID of bootable system's directory: {0}", mdb.drFndrInfo0).AppendLine();
        sb.AppendFormat("CNID of first-run application's directory: {0}", mdb.drFndrInfo1).AppendLine();
        sb.AppendFormat("CNID of previously opened directory: {0}", mdb.drFndrInfo2).AppendLine();
        sb.AppendFormat("CNID of bootable Mac OS 8 or 9 directory: {0}", mdb.drFndrInfo3).AppendLine();
        sb.AppendFormat("CNID of bootable Mac OS X directory: {0}", mdb.drFndrInfo5).AppendLine();

        if(mdb.drFndrInfo6 != 0 &&
           mdb.drFndrInfo7 != 0)
            sb.AppendFormat("Mac OS X Volume ID: {0:X8}{1:X8}", mdb.drFndrInfo6, mdb.drFndrInfo7).AppendLine();

        if(mdb.drEmbedSigWord == AppleCommon.HFSP_MAGIC)
        {
            sb.AppendLine("Volume wraps a HFS+ volume.");
            sb.AppendFormat("Starting block of the HFS+ volume: {0}", mdb.xdrStABNt).AppendLine();
            sb.AppendFormat("Allocations blocks of the HFS+ volume: {0}", mdb.xdrNumABlks).AppendLine();
        }
        else
        {
            sb.AppendFormat("{0} blocks in volume cache", mdb.drVCSize).AppendLine();
            sb.AppendFormat("{0} blocks in volume bitmap cache", mdb.drVBMCSize).AppendLine();
            sb.AppendFormat("{0} blocks in volume common cache", mdb.drCtlCSize).AppendLine();
        }

        string bootBlockInfo = AppleCommon.GetBootBlockInformation(bbSector, Encoding);

        if(bootBlockInfo != null)
        {
            sb.AppendLine("Volume is bootable.");
            sb.AppendLine();
            sb.AppendLine(bootBlockInfo);
        }
        else if(mdb.drFndrInfo0 != 0 ||
                mdb.drFndrInfo3 != 0 ||
                mdb.drFndrInfo5 != 0)
            sb.AppendLine("Volume is bootable.");
        else
            sb.AppendLine("Volume is not bootable.");

        information = sb.ToString();

        XmlFsType = new FileSystemType();

        if(mdb.drVolBkUp > 0)
        {
            XmlFsType.BackupDate          = DateHandlers.MacToDateTime(mdb.drVolBkUp);
            XmlFsType.BackupDateSpecified = true;
        }

        XmlFsType.Bootable = bootBlockInfo   != null || mdb.drFndrInfo0 != 0 || mdb.drFndrInfo3 != 0 ||
                             mdb.drFndrInfo5 != 0;

        XmlFsType.Clusters    = mdb.drNmAlBlks;
        XmlFsType.ClusterSize = mdb.drAlBlkSiz;

        if(mdb.drCrDate > 0)
        {
            XmlFsType.CreationDate          = DateHandlers.MacToDateTime(mdb.drCrDate);
            XmlFsType.CreationDateSpecified = true;
        }

        XmlFsType.Dirty                 = !mdb.drAtrb.HasFlag(AppleCommon.VolumeAttributes.Unmounted);
        XmlFsType.Files                 = mdb.drFilCnt;
        XmlFsType.FilesSpecified        = true;
        XmlFsType.FreeClusters          = mdb.drFreeBks;
        XmlFsType.FreeClustersSpecified = true;

        if(mdb.drLsMod > 0)
        {
            XmlFsType.ModificationDate          = DateHandlers.MacToDateTime(mdb.drLsMod);
            XmlFsType.ModificationDateSpecified = true;
        }

        XmlFsType.Type       = "HFS";
        XmlFsType.VolumeName = StringHandlers.PascalToString(mdb.drVN, Encoding);

        if(mdb.drFndrInfo6 != 0 &&
           mdb.drFndrInfo7 != 0)
            XmlFsType.VolumeSerial = $"{mdb.drFndrInfo6:X8}{mdb.drFndrInfo7:X8}";
    }
}