From 476ae51494488c5c25e2fcb0c1e82fe83ca3934c Mon Sep 17 00:00:00 2001 From: Natalia Portillo Date: Fri, 10 Apr 2026 21:14:19 +0100 Subject: [PATCH] [ext2/3/4] Add support for analyze command --- Aaru.Filesystems/ext2FS/Analyze.cs | 284 +++++++++++++++++++++++++++++ 1 file changed, 284 insertions(+) create mode 100644 Aaru.Filesystems/ext2FS/Analyze.cs diff --git a/Aaru.Filesystems/ext2FS/Analyze.cs b/Aaru.Filesystems/ext2FS/Analyze.cs new file mode 100644 index 000000000..be08e6b1f --- /dev/null +++ b/Aaru.Filesystems/ext2FS/Analyze.cs @@ -0,0 +1,284 @@ +// /*************************************************************************** +// Aaru Data Preservation Suite +// ---------------------------------------------------------------------------- +// +// Filename : Analyze.cs +// Author(s) : Natalia Portillo +// +// Component : Linux extended filesystem 2, 3 and 4 plugin. +// +// --[ 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 . +// +// ---------------------------------------------------------------------------- +// Copyright © 2011-2026 Natalia Portillo +// ****************************************************************************/ + +using System; +using System.Collections.Generic; +using System.Linq; +using Aaru.CommonTypes; +using Aaru.CommonTypes.Enums; +using Aaru.CommonTypes.Structs; + +namespace Aaru.Filesystems; + +// ReSharper disable once InconsistentNaming +public sealed partial class ext2FS +{ +#region IReadOnlyFilesystem Members + + /// + public ErrorNumber GetFilesWithAffectedSectors(IEnumerable<(ulong Start, ulong End)> sectorExtents, + out List files, + InitProgressHandler initProgress = null, + UpdateProgressHandler updateProgress = null, + PulseProgressHandler pulseProgress = null, + EndProgressHandler endProgress = null) + { + files = []; + + if(!_mounted) return ErrorNumber.AccessDenied; + if(sectorExtents is null) return ErrorNumber.InvalidArgument; + + List<(ulong Start, ulong End)> normalizedExtents = NormalizeAnalyzeExtents(sectorExtents); + + if(normalizedExtents.Count == 0) return ErrorNumber.NoError; + + try + { + initProgress?.Invoke(); + + return TraverseDirectoryForAffectedSectors("/", + EXT2_ROOT_INO, + normalizedExtents, + files, + updateProgress, + pulseProgress); + } + finally + { + endProgress?.Invoke(); + } + } + +#endregion + + ErrorNumber TraverseDirectoryForAffectedSectors(string path, uint directoryInodeNumber, + List<(ulong Start, ulong End)> sectorExtents, + List files, UpdateProgressHandler updateProgress, + PulseProgressHandler pulseProgress) + { + pulseProgress?.Invoke(path); + + ErrorNumber errno = ReadInode(directoryInodeNumber, out Inode directoryInode); + + if(errno != ErrorNumber.NoError) return errno; + if((directoryInode.mode & S_IFMT) != S_IFDIR) return ErrorNumber.NotDirectory; + + errno = GetDirectoryEntries(directoryInodeNumber, + directoryInode, + out Dictionary directoryEntries); + + if(errno != ErrorNumber.NoError) return errno; + + KeyValuePair[] orderedEntries = directoryEntries + .Where(static entry => + !string.IsNullOrWhiteSpace(entry.Key) && + entry.Key is not "." and not "..") + .OrderBy(static entry => entry.Key, StringComparer.Ordinal) + .ToArray(); + + long maximum = orderedEntries.Length > 0 ? orderedEntries.Length : 1; + + for(var i = 0; i < orderedEntries.Length; i++) + { + string entryPath = path == "/" ? "/" + orderedEntries[i].Key : path + "/" + orderedEntries[i].Key; + + updateProgress?.Invoke(entryPath, i + 1, maximum); + + errno = ReadInode(orderedEntries[i].Value, out Inode inode); + + if(errno != ErrorNumber.NoError) return errno; + + if((inode.mode & S_IFMT) == S_IFDIR) + { + errno = TraverseDirectoryForAffectedSectors(entryPath, + orderedEntries[i].Value, + sectorExtents, + files, + updateProgress, + pulseProgress); + + if(errno != ErrorNumber.NoError) return errno; + + continue; + } + + errno = AddOverlappingFile(entryPath, orderedEntries[i].Value, inode, sectorExtents, files); + + if(errno != ErrorNumber.NoError) return errno; + } + + return ErrorNumber.NoError; + } + + ErrorNumber GetDirectoryEntries(uint directoryInodeNumber, in Inode directoryInode, + out Dictionary directoryEntries) + { + if(directoryInodeNumber == EXT2_ROOT_INO) + { + directoryEntries = new Dictionary(_rootDirectoryCache, StringComparer.Ordinal); + + return ErrorNumber.NoError; + } + + ulong directorySize = (ulong)directoryInode.size_high << 32 | directoryInode.size_lo; + + return ReadDirectoryEntries(directoryInode, directoryInodeNumber, directorySize, out directoryEntries); + } + + ErrorNumber AddOverlappingFile(string path, uint inodeNumber, in Inode inode, + IReadOnlyList<(ulong Start, ulong End)> sectorExtents, List files) + { + ulong logicalSize = (ulong)inode.size_high << 32 | inode.size_lo; + + if(logicalSize == 0) return ErrorNumber.NoError; + + List<(ulong Start, ulong End)> overlaps; + + if((inode.i_flags & EXT4_INLINE_DATA_FL) != 0) + overlaps = FindInlineOverlaps(inodeNumber, logicalSize, sectorExtents); + else + { + ErrorNumber errno = GetInodeDataBlocks(inode, + out List<(ulong physicalBlock, uint length, bool unwritten)> + blockList); + + if(errno != ErrorNumber.NoError) return errno; + + overlaps = FindOverlappingExtents(blockList, logicalSize, sectorExtents); + } + + if(overlaps.Count == 0) return ErrorNumber.NoError; + + files.Add(new FileSectorInfo + { + Path = path, + Inode = inodeNumber, + AffectedSectors = overlaps + }); + + return ErrorNumber.NoError; + } + + List<(ulong Start, ulong End)> FindInlineOverlaps(uint inodeNumber, ulong logicalSize, + IReadOnlyList<(ulong Start, ulong End)> sectorExtents) + { + List<(ulong Start, ulong End)> overlaps = []; + + ErrorNumber errno = GetInodeByteOffset(inodeNumber, out ulong inodeByteOffset); + + if(errno != ErrorNumber.NoError) return overlaps; + + ulong sectorSize = _imagePlugin.Info.SectorSize; + ulong bytesInExtent = Math.Max(1, Math.Min(logicalSize, _inodeSize)); + ulong startSector = _partition.Start + inodeByteOffset / sectorSize; + ulong offsetInSector = inodeByteOffset % sectorSize; + ulong sectorCount = (bytesInExtent + offsetInSector + sectorSize - 1) / sectorSize; + + if(sectorCount == 0) sectorCount = 1; + + AddExtentOverlaps(startSector, startSector + sectorCount - 1, sectorExtents, overlaps); + + return NormalizeAnalyzeExtents(overlaps); + } + + List<(ulong Start, ulong End)> FindOverlappingExtents( + IReadOnlyList<(ulong physicalBlock, uint length, bool unwritten)> blockList, ulong logicalSize, + IReadOnlyList<(ulong Start, ulong End)> sectorExtents) + { + List<(ulong Start, ulong End)> overlaps = []; + ulong remainingBytes = logicalSize; + ulong sectorSize = _imagePlugin.Info.SectorSize; + + foreach((ulong physicalBlock, uint length, bool unwritten) extent in blockList) + { + if(remainingBytes == 0) break; + + if(extent.length == 0) continue; + + ulong extentBytes = Math.Min((ulong)extent.length * _blockSize, remainingBytes); + + if(extentBytes == 0) break; + + ulong byteOffset = extent.physicalBlock * _blockSize; + ulong startSector = _partition.Start + byteOffset / sectorSize; + ulong offsetInSector = byteOffset % sectorSize; + ulong sectorsInExtent = (extentBytes + offsetInSector + sectorSize - 1) / sectorSize; + + if(sectorsInExtent == 0) sectorsInExtent = 1; + + AddExtentOverlaps(startSector, startSector + sectorsInExtent - 1, sectorExtents, overlaps); + + remainingBytes -= extentBytes; + } + + return NormalizeAnalyzeExtents(overlaps); + } + + static void AddExtentOverlaps(ulong startSector, ulong endSector, + IReadOnlyList<(ulong Start, ulong End)> sectorExtents, + List<(ulong Start, ulong End)> overlaps) + { + foreach((ulong Start, ulong End) requestedExtent in sectorExtents) + { + if(requestedExtent.End < startSector || requestedExtent.Start > endSector) continue; + + overlaps.Add((Math.Max(startSector, requestedExtent.Start), Math.Min(endSector, requestedExtent.End))); + } + } + + static List<(ulong Start, ulong End)> NormalizeAnalyzeExtents(IEnumerable<(ulong Start, ulong End)> extents) + { + var orderedExtents = extents.Where(static extent => extent.End >= extent.Start) + .OrderBy(static extent => extent.Start) + .ThenBy(static extent => extent.End) + .ToList(); + + List<(ulong Start, ulong End)> normalizedExtents = []; + + if(orderedExtents.Count == 0) return normalizedExtents; + + (ulong Start, ulong End) currentExtent = orderedExtents[0]; + + for(var i = 1; i < orderedExtents.Count; i++) + { + if(orderedExtents[i].Start <= currentExtent.End + 1) + { + currentExtent.End = Math.Max(currentExtent.End, orderedExtents[i].End); + + continue; + } + + normalizedExtents.Add(currentExtent); + currentExtent = orderedExtents[i]; + } + + normalizedExtents.Add(currentExtent); + + return normalizedExtents; + } +} \ No newline at end of file