From f723c1c4402b25f9810a47911cd20efd7d9ec691 Mon Sep 17 00:00:00 2001 From: Natalia Portillo Date: Wed, 17 Jan 2018 15:35:17 +0000 Subject: [PATCH] Add writing support to QEMU Copy-On-Write disk image. --- DiscImageChef.DiscImages/QCOW.cs | 434 +++++++++++++++++++++++++------ 1 file changed, 354 insertions(+), 80 deletions(-) diff --git a/DiscImageChef.DiscImages/QCOW.cs b/DiscImageChef.DiscImages/QCOW.cs index 27e520a7..c415a6dc 100644 --- a/DiscImageChef.DiscImages/QCOW.cs +++ b/DiscImageChef.DiscImages/QCOW.cs @@ -33,6 +33,7 @@ using System; using System.Collections.Generic; using System.IO; +using System.Linq; using System.Runtime.InteropServices; using DiscImageChef.CommonTypes; using DiscImageChef.Console; @@ -42,65 +43,66 @@ using SharpCompress.Compressors.Deflate; namespace DiscImageChef.DiscImages { - public class Qcow : IMediaImage + public class Qcow : IWritableImage { /// /// Magic number: 'Q', 'F', 'I', 0xFB /// - const uint QCOW_MAGIC = 0x514649FB; - const uint QCOW_VERSION = 1; - const uint QCOW_ENCRYPTION_NONE = 0; - const uint QCOW_ENCRYPTION_AES = 1; - const ulong QCOW_COMPRESSED = 0x8000000000000000; + const uint QCOW_MAGIC = 0x514649FB; + const uint QCOW_VERSION = 1; + const uint QCOW_ENCRYPTION_NONE = 0; + const uint QCOW_ENCRYPTION_AES = 1; + const ulong QCOW_COMPRESSED = 0x8000000000000000; const int MAX_CACHE_SIZE = 16777216; - const int MAX_CACHED_SECTORS = MAX_CACHE_SIZE / 512; + const int MAX_CACHED_SECTORS = MAX_CACHE_SIZE / 512; Dictionary clusterCache; - int clusterSectors; - int clusterSize; - ImageInfo imageInfo; + int clusterSectors; + int clusterSize; + ImageInfo imageInfo; Stream imageStream; - ulong l1Mask; - int l1Shift; - uint l1Size; - ulong[] l1Table; - ulong l2Mask; - int l2Size; + ulong l1Mask; + int l1Shift; + uint l1Size; + ulong[] l1Table; + ulong l2Mask; + int l2Size; Dictionary l2TableCache; - int maxClusterCache; - int maxL2TableCache; + int maxClusterCache; + int maxL2TableCache; QCowHeader qHdr; Dictionary sectorCache; - ulong sectorMask; + ulong sectorMask; + FileStream writingStream; public Qcow() { imageInfo = new ImageInfo { - ReadableSectorTags = new List(), - ReadableMediaTags = new List(), - HasPartitions = false, - HasSessions = false, - Version = "1", - Application = "QEMU", - ApplicationVersion = null, - Creator = null, - Comments = null, - MediaManufacturer = null, - MediaModel = null, - MediaSerialNumber = null, - MediaBarcode = null, - MediaPartNumber = null, - MediaSequence = 0, - LastMediaSequence = 0, - DriveManufacturer = null, - DriveModel = null, - DriveSerialNumber = null, + ReadableSectorTags = new List(), + ReadableMediaTags = new List(), + HasPartitions = false, + HasSessions = false, + Version = "1", + Application = "QEMU", + ApplicationVersion = null, + Creator = null, + Comments = null, + MediaManufacturer = null, + MediaModel = null, + MediaSerialNumber = null, + MediaBarcode = null, + MediaPartNumber = null, + MediaSequence = 0, + LastMediaSequence = 0, + DriveManufacturer = null, + DriveModel = null, + DriveSerialNumber = null, DriveFirmwareRevision = null }; } @@ -108,7 +110,7 @@ namespace DiscImageChef.DiscImages public ImageInfo Info => imageInfo; public string Name => "QEMU Copy-On-Write disk image"; - public Guid Id => new Guid("A5C35765-9FE2-469D-BBBF-ACDEBDB7B954"); + public Guid Id => new Guid("A5C35765-9FE2-469D-BBBF-ACDEBDB7B954"); public string Format => "QEMU Copy-On-Write"; @@ -146,17 +148,17 @@ namespace DiscImageChef.DiscImages stream.Read(qHdrB, 0, 48); qHdr = BigEndianMarshal.ByteArrayToStructureBigEndian(qHdrB); - DicConsole.DebugWriteLine("QCOW plugin", "qHdr.magic = 0x{0:X8}", qHdr.magic); - DicConsole.DebugWriteLine("QCOW plugin", "qHdr.version = {0}", qHdr.version); + DicConsole.DebugWriteLine("QCOW plugin", "qHdr.magic = 0x{0:X8}", qHdr.magic); + DicConsole.DebugWriteLine("QCOW plugin", "qHdr.version = {0}", qHdr.version); DicConsole.DebugWriteLine("QCOW plugin", "qHdr.backing_file_offset = {0}", qHdr.backing_file_offset); - DicConsole.DebugWriteLine("QCOW plugin", "qHdr.backing_file_size = {0}", qHdr.backing_file_size); - DicConsole.DebugWriteLine("QCOW plugin", "qHdr.mtime = {0}", qHdr.mtime); - DicConsole.DebugWriteLine("QCOW plugin", "qHdr.size = {0}", qHdr.size); - DicConsole.DebugWriteLine("QCOW plugin", "qHdr.cluster_bits = {0}", qHdr.cluster_bits); - DicConsole.DebugWriteLine("QCOW plugin", "qHdr.l2_bits = {0}", qHdr.l2_bits); - DicConsole.DebugWriteLine("QCOW plugin", "qHdr.padding = {0}", qHdr.padding); - DicConsole.DebugWriteLine("QCOW plugin", "qHdr.crypt_method = {0}", qHdr.crypt_method); - DicConsole.DebugWriteLine("QCOW plugin", "qHdr.l1_table_offset = {0}", qHdr.l1_table_offset); + DicConsole.DebugWriteLine("QCOW plugin", "qHdr.backing_file_size = {0}", qHdr.backing_file_size); + DicConsole.DebugWriteLine("QCOW plugin", "qHdr.mtime = {0}", qHdr.mtime); + DicConsole.DebugWriteLine("QCOW plugin", "qHdr.size = {0}", qHdr.size); + DicConsole.DebugWriteLine("QCOW plugin", "qHdr.cluster_bits = {0}", qHdr.cluster_bits); + DicConsole.DebugWriteLine("QCOW plugin", "qHdr.l2_bits = {0}", qHdr.l2_bits); + DicConsole.DebugWriteLine("QCOW plugin", "qHdr.padding = {0}", qHdr.padding); + DicConsole.DebugWriteLine("QCOW plugin", "qHdr.crypt_method = {0}", qHdr.crypt_method); + DicConsole.DebugWriteLine("QCOW plugin", "qHdr.l1_table_offset = {0}", qHdr.l1_table_offset); if(qHdr.size <= 1) throw new ArgumentOutOfRangeException(nameof(qHdr.size), "Image size is too small"); @@ -182,16 +184,16 @@ namespace DiscImageChef.DiscImages if(qHdr.size > ulong.MaxValue - (ulong)(1 << shift)) throw new ArgumentOutOfRangeException(nameof(qHdr.size), "Image is too large"); - clusterSize = 1 << qHdr.cluster_bits; + clusterSize = 1 << qHdr.cluster_bits; clusterSectors = 1 << (qHdr.cluster_bits - 9); - l1Size = (uint)((qHdr.size + (ulong)(1 << shift) - 1) >> shift); - l2Size = 1 << qHdr.l2_bits; + l1Size = (uint)((qHdr.size + (ulong)(1 << shift) - 1) >> shift); + l2Size = 1 << qHdr.l2_bits; - DicConsole.DebugWriteLine("QCOW plugin", "qHdr.clusterSize = {0}", clusterSize); + DicConsole.DebugWriteLine("QCOW plugin", "qHdr.clusterSize = {0}", clusterSize); DicConsole.DebugWriteLine("QCOW plugin", "qHdr.clusterSectors = {0}", clusterSectors); - DicConsole.DebugWriteLine("QCOW plugin", "qHdr.l1Size = {0}", l1Size); - DicConsole.DebugWriteLine("QCOW plugin", "qHdr.l2Size = {0}", l2Size); - DicConsole.DebugWriteLine("QCOW plugin", "qHdr.sectors = {0}", imageInfo.Sectors); + DicConsole.DebugWriteLine("QCOW plugin", "qHdr.l1Size = {0}", l1Size); + DicConsole.DebugWriteLine("QCOW plugin", "qHdr.l2Size = {0}", l2Size); + DicConsole.DebugWriteLine("QCOW plugin", "qHdr.sectors = {0}", imageInfo.Sectors); BigEndianBitConverter.IsLittleEndian = BitConverter.IsLittleEndian; @@ -203,8 +205,8 @@ namespace DiscImageChef.DiscImages for(long i = 0; i < l1Table.LongLength; i++) l1Table[i] = BigEndianBitConverter.ToUInt64(l1TableB, (int)(i * 8)); - l1Mask = 0; - int c = 0; + l1Mask = 0; + int c = 0; l1Shift = qHdr.l2_bits + qHdr.cluster_bits; for(int i = 0; i < 64; i++) @@ -217,17 +219,17 @@ namespace DiscImageChef.DiscImages c++; } - l2Mask = 0; + l2Mask = 0; for(int i = 0; i < qHdr.l2_bits; i++) l2Mask = (l2Mask << 1) + 1; l2Mask <<= qHdr.cluster_bits; - sectorMask = 0; + sectorMask = 0; for(int i = 0; i < qHdr.cluster_bits; i++) sectorMask = (sectorMask << 1) + 1; - DicConsole.DebugWriteLine("QCOW plugin", "qHdr.l1Mask = {0:X}", l1Mask); - DicConsole.DebugWriteLine("QCOW plugin", "qHdr.l1Shift = {0}", l1Shift); - DicConsole.DebugWriteLine("QCOW plugin", "qHdr.l2Mask = {0:X}", l2Mask); + DicConsole.DebugWriteLine("QCOW plugin", "qHdr.l1Mask = {0:X}", l1Mask); + DicConsole.DebugWriteLine("QCOW plugin", "qHdr.l1Shift = {0}", l1Shift); + DicConsole.DebugWriteLine("QCOW plugin", "qHdr.l2Mask = {0:X}", l2Mask); DicConsole.DebugWriteLine("QCOW plugin", "qHdr.sectorMask = {0:X}", sectorMask); maxL2TableCache = MAX_CACHE_SIZE / (l2Size * 8); @@ -235,23 +237,23 @@ namespace DiscImageChef.DiscImages imageStream = stream; - sectorCache = new Dictionary(); + sectorCache = new Dictionary(); l2TableCache = new Dictionary(); clusterCache = new Dictionary(); - imageInfo.CreationTime = imageFilter.GetCreationTime(); + imageInfo.CreationTime = imageFilter.GetCreationTime(); imageInfo.LastModificationTime = qHdr.mtime > 0 ? DateHandlers.UnixUnsignedToDateTime(qHdr.mtime) : imageFilter.GetLastWriteTime(); - imageInfo.MediaTitle = Path.GetFileNameWithoutExtension(imageFilter.GetFilename()); - imageInfo.Sectors = qHdr.size / 512; - imageInfo.SectorSize = 512; + imageInfo.MediaTitle = Path.GetFileNameWithoutExtension(imageFilter.GetFilename()); + imageInfo.Sectors = qHdr.size / 512; + imageInfo.SectorSize = 512; imageInfo.XmlMediaType = XmlMediaType.BlockMedia; - imageInfo.MediaType = MediaType.GENERIC_HDD; - imageInfo.ImageSize = qHdr.size; + imageInfo.MediaType = MediaType.GENERIC_HDD; + imageInfo.ImageSize = qHdr.size; - imageInfo.Cylinders = (uint)(imageInfo.Sectors / 16 / 63); - imageInfo.Heads = 16; + imageInfo.Cylinders = (uint)(imageInfo.Sectors / 16 / 63); + imageInfo.Heads = 16; imageInfo.SectorsPerTrack = 63; return true; @@ -281,7 +283,7 @@ namespace DiscImageChef.DiscImages { l2Table = new ulong[l2Size]; imageStream.Seek((long)l1Table[l1Off], SeekOrigin.Begin); - byte[] l2TableB = new byte[l2Size * 8]; + byte[] l2TableB = new byte[l2Size * 8]; imageStream.Read(l2TableB, 0, l2Size * 8); DicConsole.DebugWriteLine("QCOW plugin", "Reading L2 table #{0}", l1Off); for(long i = 0; i < l2Table.LongLength; i++) @@ -307,11 +309,11 @@ namespace DiscImageChef.DiscImages ulong compSizeMask; ulong offMask; - compSizeMask = (ulong)(1 << qHdr.cluster_bits) - 1; - compSizeMask <<= 63 - qHdr.cluster_bits; - offMask = ~compSizeMask ^ QCOW_COMPRESSED; + compSizeMask = (ulong)(1 << qHdr.cluster_bits) - 1; + compSizeMask <<= 63 - qHdr.cluster_bits; + offMask = ~compSizeMask ^ QCOW_COMPRESSED; - ulong realOff = offset & offMask; + ulong realOff = offset & offMask; ulong compSize = (offset & compSizeMask) >> (63 - qHdr.cluster_bits); byte[] zCluster = new byte[compSize]; @@ -320,7 +322,7 @@ namespace DiscImageChef.DiscImages DeflateStream zStream = new DeflateStream(new MemoryStream(zCluster), CompressionMode.Decompress); - cluster = new byte[clusterSize]; + cluster = new byte[clusterSize]; int read = zStream.Read(cluster, 0, clusterSize); if(read != clusterSize) @@ -445,7 +447,7 @@ namespace DiscImageChef.DiscImages } public bool? VerifySectors(ulong sectorAddress, uint length, out List failingLbas, - out List unknownLbas) + out List unknownLbas) { failingLbas = new List(); unknownLbas = new List(); @@ -455,7 +457,7 @@ namespace DiscImageChef.DiscImages } public bool? VerifySectors(ulong sectorAddress, uint length, uint track, out List failingLbas, - out List unknownLbas) + out List unknownLbas) { throw new FeatureUnsupportedImageException("Feature not supported by image format"); } @@ -465,6 +467,278 @@ namespace DiscImageChef.DiscImages return null; } + public IEnumerable SupportedMediaTags => new MediaTagType[] { }; + public IEnumerable SupportedSectorTags => new SectorTagType[] { }; + public IEnumerable SupportedMediaTypes => + new[] {MediaType.Unknown, MediaType.GENERIC_HDD}; + public IEnumerable<(string name, Type type, string description)> SupportedOptions => + new (string name, Type type, string description)[] { }; + public IEnumerable KnownExtensions => new[] {".qcow", ".qc"}; + public bool IsWriting { get; private set; } + public string ErrorMessage { get; private set; } + + public bool Create(string path, MediaType mediaType, Dictionary options, ulong sectors, + uint sectorSize) + { + if(sectorSize != 512) + { + ErrorMessage = "Unsupported sector size"; + return false; + } + + if(!SupportedMediaTypes.Contains(mediaType)) + { + ErrorMessage = $"Unsupport media format {mediaType}"; + return false; + } + + // TODO: Correct this calculation + if(sectors * sectorSize / 65536 > uint.MaxValue) + { + ErrorMessage = "Too many sectors for selected cluster size"; + return false; + } + + imageInfo = new ImageInfo {MediaType = mediaType, SectorSize = sectorSize, Sectors = sectors}; + + try { writingStream = new FileStream(path, FileMode.CreateNew, FileAccess.ReadWrite, FileShare.None); } + catch(IOException e) + { + ErrorMessage = $"Could not create new image file, exception {e.Message}"; + return false; + } + + qHdr = new QCowHeader + { + magic = QCOW_MAGIC, + version = QCOW_VERSION, + size = sectors * sectorSize, + cluster_bits = 12, + l2_bits = 9, + l1_table_offset = (ulong)Marshal.SizeOf(typeof(QCowHeader)) + }; + + int shift = qHdr.cluster_bits + qHdr.l2_bits; + clusterSize = 1 << qHdr.cluster_bits; + clusterSectors = 1 << (qHdr.cluster_bits - 9); + l1Size = (uint)((qHdr.size + (ulong)(1 << shift) - 1) >> shift); + l2Size = 1 << qHdr.l2_bits; + + l1Table = new ulong[l1Size]; + + l1Mask = 0; + int c = 0; + l1Shift = qHdr.l2_bits + qHdr.cluster_bits; + + for(int i = 0; i < 64; i++) + { + l1Mask <<= 1; + + if(c >= 64 - l1Shift) continue; + + l1Mask += 1; + c++; + } + + l2Mask = 0; + for(int i = 0; i < qHdr.l2_bits; i++) l2Mask = (l2Mask << 1) + 1; + + l2Mask <<= qHdr.cluster_bits; + + sectorMask = 0; + for(int i = 0; i < qHdr.cluster_bits; i++) sectorMask = (sectorMask << 1) + 1; + + byte[] empty = new byte[qHdr.l1_table_offset + l1Size * 8]; + writingStream.Write(empty, 0, empty.Length); + + IsWriting = true; + ErrorMessage = null; + return true; + } + + public bool WriteMediaTag(byte[] data, MediaTagType tag) + { + ErrorMessage = "Writing media tags is not supported."; + return false; + } + + public bool WriteSector(byte[] data, ulong sectorAddress) + { + if(!IsWriting) + { + ErrorMessage = "Tried to write on a non-writable image"; + return false; + } + + if(data.Length != imageInfo.SectorSize) + { + ErrorMessage = "Incorrect data size"; + return false; + } + + if(sectorAddress >= imageInfo.Sectors) + { + ErrorMessage = "Tried to write past image size"; + return false; + } + + // Ignore empty sectors + if(ArrayHelpers.ArrayIsNullOrEmpty(data)) return true; + + ulong byteAddress = sectorAddress * 512; + + ulong l1Off = (byteAddress & l1Mask) >> l1Shift; + + if((long)l1Off >= l1Table.LongLength) + throw new ArgumentOutOfRangeException(nameof(l1Off), + $"Trying to write past L1 table, position {l1Off} of a max {l1Table.LongLength}"); + + if(l1Table[l1Off] == 0) + { + writingStream.Seek(0, SeekOrigin.End); + l1Table[l1Off] = (ulong)writingStream.Position; + byte[] l2TableB = new byte[l2Size * 8]; + writingStream.Seek(0, SeekOrigin.End); + writingStream.Write(l2TableB, 0, l2TableB.Length); + } + + writingStream.Position = (long)l1Table[l1Off]; + + ulong l2Off = (byteAddress & l2Mask) >> qHdr.cluster_bits; + + writingStream.Seek((long)(l1Table[l1Off] + l2Off * 8), SeekOrigin.Begin); + + BigEndianBitConverter.IsLittleEndian = BitConverter.IsLittleEndian; + + byte[] entry = new byte[8]; + writingStream.Read(entry, 0, 8); + ulong offset = BigEndianBitConverter.ToUInt64(entry, 0); + + if(offset == 0) + { + offset = (ulong)writingStream.Length; + byte[] cluster = new byte[clusterSize]; + entry = BigEndianBitConverter.GetBytes(offset); + writingStream.Seek((long)(l1Table[l1Off] + l2Off * 8), SeekOrigin.Begin); + writingStream.Write(entry, 0, 8); + writingStream.Seek(0, SeekOrigin.End); + writingStream.Write(cluster, 0, cluster.Length); + } + + writingStream.Seek((long)(offset + (byteAddress & sectorMask)), SeekOrigin.Begin); + writingStream.Write(data, 0, data.Length); + + ErrorMessage = ""; + return true; + } + + // TODO: This can be optimized + public bool WriteSectors(byte[] data, ulong sectorAddress, uint length) + { + if(!IsWriting) + { + ErrorMessage = "Tried to write on a non-writable image"; + return false; + } + + if(data.Length % imageInfo.SectorSize != 0) + { + ErrorMessage = "Incorrect data size"; + return false; + } + + if(sectorAddress + length > imageInfo.Sectors) + { + ErrorMessage = "Tried to write past image size"; + return false; + } + + // Ignore empty sectors + if(ArrayHelpers.ArrayIsNullOrEmpty(data)) return true; + + for(uint i = 0; i < length; i++) + { + byte[] tmp = new byte[imageInfo.SectorSize]; + Array.Copy(data, i * imageInfo.SectorSize, tmp, 0, imageInfo.SectorSize); + if(!WriteSector(tmp, sectorAddress + i)) return false; + } + + ErrorMessage = ""; + return true; + } + + public bool WriteSectorLong(byte[] data, ulong sectorAddress) + { + ErrorMessage = "Writing sectors with tags is not supported."; + return false; + } + + public bool WriteSectorsLong(byte[] data, ulong sectorAddress, uint length) + { + ErrorMessage = "Writing sectors with tags is not supported."; + return false; + } + + public bool SetTracks(List tracks) + { + ErrorMessage = "Unsupported feature"; + return false; + } + + public bool Close() + { + if(!IsWriting) + { + ErrorMessage = "Image is not opened for writing"; + return false; + } + + qHdr.mtime = (uint)(DateTime.Now - new DateTime(1970, 1, 1, 0, 0, 0)).TotalSeconds; + + BigEndianBitConverter.IsLittleEndian = BitConverter.IsLittleEndian; + writingStream.Seek(0, SeekOrigin.Begin); + writingStream.Write(BigEndianBitConverter.GetBytes(qHdr.magic), 0, 4); + writingStream.Write(BigEndianBitConverter.GetBytes(qHdr.version), 0, 4); + writingStream.Write(BigEndianBitConverter.GetBytes(qHdr.backing_file_offset), 0, 8); + writingStream.Write(BigEndianBitConverter.GetBytes(qHdr.backing_file_size), 0, 4); + writingStream.Write(BigEndianBitConverter.GetBytes(qHdr.mtime), 0, 4); + writingStream.Write(BigEndianBitConverter.GetBytes(qHdr.size), 0, 8); + writingStream.WriteByte(qHdr.cluster_bits); + writingStream.WriteByte(qHdr.l2_bits); + writingStream.Write(BigEndianBitConverter.GetBytes(qHdr.padding), 0, 2); + writingStream.Write(BigEndianBitConverter.GetBytes(qHdr.crypt_method), 0, 4); + writingStream.Write(BigEndianBitConverter.GetBytes(qHdr.l1_table_offset), 0, 8); + + writingStream.Seek((long)qHdr.l1_table_offset, SeekOrigin.Begin); + for(long i = 0; i < l1Table.LongLength; i++) + writingStream.Write(BigEndianBitConverter.GetBytes(l1Table[i]), 0, 8); + + return true; + } + + public bool SetMetadata(ImageInfo metadata) + { + return true; + } + + public bool SetGeometry(uint cylinders, uint heads, uint sectorsPerTrack) + { + // Not stored in image + return true; + } + + public bool WriteSectorTag(byte[] data, ulong sectorAddress, SectorTagType tag) + { + ErrorMessage = "Writing sectors with tags is not supported."; + return false; + } + + public bool WriteSectorsTag(byte[] data, ulong sectorAddress, uint length, SectorTagType tag) + { + ErrorMessage = "Writing sectors with tags is not supported."; + return false; + } + /// /// QCOW header, big-endian ///