/// <summary>
/// Looks like this function reads beginning of the header described in
/// ECMA-335 24.2.1 Metadata root
/// </summary>
private void ReadMetadataHeader(ref BlobReader memReader, out string versionString)
{
if (memReader.RemainingBytes < COR20Constants.MinimumSizeofMetadataHeader)
{
throw new BadImageFormatException("MetadataHeaderTooSmall");
}
uint signature = memReader.ReadUInt32();
if (signature != COR20Constants.COR20MetadataSignature)
{
throw new BadImageFormatException("MetadataSignature");
}
// major version
memReader.ReadUInt16();
// minor version
memReader.ReadUInt16();
// reserved:
memReader.ReadUInt32();
int versionStringSize = memReader.ReadInt32();
if (memReader.RemainingBytes < versionStringSize)
{
throw new BadImageFormatException("NotEnoughSpaceForVersionString");
}
int numberOfBytesRead;
versionString = memReader.GetMemoryBlockAt(0, versionStringSize).PeekUtf8NullTerminated(0, out numberOfBytesRead);
memReader.Offset += versionStringSize;
}
public unsafe MetadataReader(byte *metadata, int length, MetadataReaderOptions options)
{
// Do not throw here when length is 0. We'll throw BadImageFormatException later on, so that the caller doesn't need to
// worry about the image (stream) being empty and can handle all image errors by catching BadImageFormatException.
if (length < 0)
{
throw new ArgumentOutOfRangeException(nameof(length));
}
if (metadata == null)
{
throw new ArgumentNullException(nameof(metadata));
}
this.Block = new MemoryBlock(metadata, length);
_options = options;
var headerReader = new BlobReader(this.Block);
this.ReadMetadataHeader(ref headerReader, out _versionString);
_metadataKind = GetMetadataKind(_versionString);
var streamHeaders = this.ReadStreamHeaders(ref headerReader);
// storage header and stream headers:
MemoryBlock metadataTableStream;
MemoryBlock standalonePdbStream;
this.InitializeStreamReaders(ref this.Block, streamHeaders, out _metadataStreamKind, out metadataTableStream, out standalonePdbStream);
int[] externalTableRowCountsOpt;
if (standalonePdbStream.Length > 0)
{
ReadStandalonePortablePdbStream(standalonePdbStream, out _debugMetadataHeader, out externalTableRowCountsOpt);
}
else
{
externalTableRowCountsOpt = null;
}
var tableReader = new BlobReader(metadataTableStream);
HeapSizes heapSizes;
int[] metadataTableRowCounts;
this.ReadMetadataTableHeader(ref tableReader, out heapSizes, out metadataTableRowCounts, out _sortedTables);
this.InitializeTableReaders(tableReader.GetMemoryBlockAt(0, tableReader.RemainingBytes), heapSizes, metadataTableRowCounts, externalTableRowCountsOpt);
}
public static MethodBodyBlock Create(BlobReader reader)
{
int startOffset = reader.Offset;
int ilSize;
// Error need to check if the Memory Block is empty. This is false for all the calls...
byte headByte = reader.ReadByte();
if ((headByte & ILFormatMask) == ILTinyFormat)
{
// tiny IL can't have locals so technically this shouldn't matter,
// but false is consistent with other metadata readers and helps
// for use cases involving comparing our output with theirs.
const bool initLocalsForTinyIL = false;
ilSize = headByte >> ILTinyFormatSizeShift;
return(new MethodBodyBlock(
initLocalsForTinyIL,
8,
default(StandaloneSignatureHandle),
reader.GetMemoryBlockAt(0, ilSize),
ImmutableArray <ExceptionRegion> .Empty,
1 + ilSize // header + IL
));
}
if ((headByte & ILFormatMask) != ILFatFormat)
{
throw new BadImageFormatException(SR.Format(SR.InvalidMethodHeader1, headByte));
}
// FatILFormat
byte headByte2 = reader.ReadByte();
if ((headByte2 >> ILFatFormatHeaderSizeShift) != ILFatFormatHeaderSize)
{
throw new BadImageFormatException(SR.Format(SR.InvalidMethodHeader2, headByte, headByte2));
}
bool localsInitialized = (headByte & ILInitLocals) == ILInitLocals;
bool hasExceptionHandlers = (headByte & ILMoreSects) == ILMoreSects;
ushort maxStack = reader.ReadUInt16();
ilSize = reader.ReadInt32();
int localSignatureToken = reader.ReadInt32();
StandaloneSignatureHandle localSignatureHandle;
if (localSignatureToken == 0)
{
localSignatureHandle = default(StandaloneSignatureHandle);
}
else if ((localSignatureToken & TokenTypeIds.TypeMask) == TokenTypeIds.Signature)
{
localSignatureHandle = StandaloneSignatureHandle.FromRowId((int)((uint)localSignatureToken & TokenTypeIds.RIDMask));
}
else
{
throw new BadImageFormatException(SR.Format(SR.InvalidLocalSignatureToken, unchecked ((uint)localSignatureToken)));
}
var ilBlock = reader.GetMemoryBlockAt(0, ilSize);
reader.Offset += ilSize;
ImmutableArray <ExceptionRegion> exceptionHandlers;
if (hasExceptionHandlers)
{
reader.Align(4);
byte sehHeader = reader.ReadByte();
if ((sehHeader & SectEHTable) != SectEHTable)
{
throw new BadImageFormatException(SR.Format(SR.InvalidSehHeader, sehHeader));
}
bool sehFatFormat = (sehHeader & SectFatFormat) == SectFatFormat;
int dataSize = reader.ReadByte();
if (sehFatFormat)
{
dataSize += reader.ReadUInt16() << 8;
exceptionHandlers = ReadFatExceptionHandlers(ref reader, dataSize / 24);
}
else
{
reader.Offset += 2; // skip over reserved field
exceptionHandlers = ReadSmallExceptionHandlers(ref reader, dataSize / 12);
}
}
else
{
exceptionHandlers = ImmutableArray <ExceptionRegion> .Empty;
}
return(new MethodBodyBlock(
localsInitialized,
maxStack,
localSignatureHandle,
ilBlock,
exceptionHandlers,
reader.Offset - startOffset));
}
/// <summary>
/// Creates a metadata reader from the metadata stored at the given memory location.
/// </summary>
/// <remarks>
/// The memory is owned by the caller and it must be kept memory alive and unmodified throughout the lifetime of the <see cref="MetadataReader"/>.
/// Use <see cref="PEReaderExtensions.GetMetadataReader(PortableExecutable.PEReader, MetadataReaderOptions, MetadataStringDecoder)"/> to obtain
/// metadata from a PE image.
/// </remarks>
public unsafe MetadataReader(byte* metadata, int length, MetadataReaderOptions options, MetadataStringDecoder utf8Decoder)
{
if (length <= 0)
{
throw new ArgumentOutOfRangeException("length");
}
if (metadata == null)
{
throw new ArgumentNullException("metadata");
}
if (utf8Decoder == null)
{
utf8Decoder = MetadataStringDecoder.DefaultUTF8;
}
if (!(utf8Decoder.Encoding is UTF8Encoding))
{
throw new ArgumentException(MetadataResources.MetadataStringDecoderEncodingMustBeUtf8, "utf8Decoder");
}
if (!BitConverter.IsLittleEndian)
{
throw new PlatformNotSupportedException(MetadataResources.LitteEndianArchitectureRequired);
}
this.Block = new MemoryBlock(metadata, length);
this.options = options;
this.utf8Decoder = utf8Decoder;
BlobReader memReader = new BlobReader(this.Block);
this.ReadMetadataHeader(ref memReader);
// storage header and stream headers:
MemoryBlock metadataTableStream;
var streamHeaders = this.ReadStreamHeaders(ref memReader);
this.InitializeStreamReaders(ref this.Block, streamHeaders, out metadataTableStream);
memReader = new BlobReader(metadataTableStream);
uint[] metadataTableRowCounts;
this.ReadMetadataTableHeader(ref memReader, out metadataTableRowCounts);
this.InitializeTableReaders(memReader.GetMemoryBlockAt(0, memReader.RemainingBytes), metadataTableRowCounts);
// This previously could occur in obfuscated assemblies but a check was added to prevent
// it getting to this point
Debug.Assert(this.AssemblyTable.NumberOfRows <= 1);
// Although the specification states that the module table will have exactly one row,
// the native metadata reader would successfully read files containing more than one row.
// Such files exist in the wild and may be produced by obfuscators.
if (this.ModuleTable.NumberOfRows < 1)
{
throw new BadImageFormatException(string.Format(MetadataResources.ModuleTableInvalidNumberOfRows, this.ModuleTable.NumberOfRows));
}
// read
this.namespaceCache = new NamespaceCache(this);
if (this.metadataKind != MetadataKind.Ecma335)
{
this.WinMDMscorlibRef = FindMscorlibAssemblyRefNoProjection();
}
}
/// <summary>
/// Looks like this function reads beginning of the header described in
/// Ecma-335 24.2.1 Metadata root
/// </summary>
private void ReadMetadataHeader(ref BlobReader memReader)
{
if (memReader.RemainingBytes < COR20Constants.MinimumSizeofMetadataHeader)
{
throw new BadImageFormatException(MetadataResources.MetadataHeaderTooSmall);
}
this.metadataHeader.Signature = memReader.ReadUInt32();
if (this.metadataHeader.Signature != COR20Constants.COR20MetadataSignature)
{
throw new BadImageFormatException(MetadataResources.MetadataSignature);
}
this.metadataHeader.MajorVersion = memReader.ReadUInt16();
this.metadataHeader.MinorVersion = memReader.ReadUInt16();
this.metadataHeader.ExtraData = memReader.ReadUInt32();
this.metadataHeader.VersionStringSize = memReader.ReadInt32();
if (memReader.RemainingBytes < this.metadataHeader.VersionStringSize)
{
throw new BadImageFormatException(MetadataResources.NotEnoughSpaceForVersionString);
}
int numberOfBytesRead;
this.metadataHeader.VersionString = memReader.GetMemoryBlockAt(0, this.metadataHeader.VersionStringSize).PeekUtf8NullTerminated(0, null, utf8Decoder, out numberOfBytesRead, '\0');
memReader.SkipBytes(this.metadataHeader.VersionStringSize);
this.metadataKind = GetMetadataKind(metadataHeader.VersionString);
}
/// <summary>
/// Creates a metadata reader from the metadata stored at the given memory location.
/// </summary>
/// <remarks>
/// The memory is owned by the caller and it must be kept memory alive and unmodified throughout the lifetime of the <see cref="MetadataReader"/>.
/// Use <see cref="PEReaderExtensions.GetMetadataReader(PortableExecutable.PEReader, MetadataReaderOptions, MetadataStringDecoder)"/> to obtain
/// metadata from a PE image.
/// </remarks>
/// <exception cref="ArgumentOutOfRangeException"><paramref name="length"/> is not positive.</exception>
/// <exception cref="ArgumentNullException"><paramref name="metadata"/> is null.</exception>
/// <exception cref="ArgumentException">The encoding of <paramref name="utf8Decoder"/> is not <see cref="UTF8Encoding"/>.</exception>
/// <exception cref="PlatformNotSupportedException">The current platform is big-endian.</exception>
public unsafe MetadataReader(byte* metadata, int length, MetadataReaderOptions options, MetadataStringDecoder utf8Decoder)
{
// Do not throw here when length is 0. We'll throw BadImageFormatException later on, so that the caller doesn't need to
// worry about the image (stream) being empty and can handle all image errors by catching BadImageFormatException.
if (length < 0)
{
throw new ArgumentOutOfRangeException(nameof(length));
}
if (metadata == null)
{
throw new ArgumentNullException(nameof(metadata));
}
if (utf8Decoder == null)
{
utf8Decoder = MetadataStringDecoder.DefaultUTF8;
}
if (!(utf8Decoder.Encoding is UTF8Encoding))
{
throw new ArgumentException(SR.MetadataStringDecoderEncodingMustBeUtf8, nameof(utf8Decoder));
}
if (!BitConverter.IsLittleEndian)
{
Throw.LitteEndianArchitectureRequired();
}
this.Block = new MemoryBlock(metadata, length);
_options = options;
this.UTF8Decoder = utf8Decoder;
var headerReader = new BlobReader(this.Block);
this.ReadMetadataHeader(ref headerReader, out _versionString);
_metadataKind = GetMetadataKind(_versionString);
var streamHeaders = this.ReadStreamHeaders(ref headerReader);
// storage header and stream headers:
MemoryBlock metadataTableStream;
MemoryBlock standalonePdbStream;
this.InitializeStreamReaders(ref this.Block, streamHeaders, out _metadataStreamKind, out metadataTableStream, out standalonePdbStream);
int[] externalTableRowCountsOpt;
if (standalonePdbStream.Length > 0)
{
ReadStandalonePortablePdbStream(standalonePdbStream, out _debugMetadataHeader, out externalTableRowCountsOpt);
}
else
{
externalTableRowCountsOpt = null;
}
var tableReader = new BlobReader(metadataTableStream);
HeapSizes heapSizes;
int[] metadataTableRowCounts;
this.ReadMetadataTableHeader(ref tableReader, out heapSizes, out metadataTableRowCounts, out _sortedTables);
this.InitializeTableReaders(tableReader.GetMemoryBlockAt(0, tableReader.RemainingBytes), heapSizes, metadataTableRowCounts, externalTableRowCountsOpt);
// This previously could occur in obfuscated assemblies but a check was added to prevent
// it getting to this point
Debug.Assert(this.AssemblyTable.NumberOfRows <= 1);
// Although the specification states that the module table will have exactly one row,
// the native metadata reader would successfully read files containing more than one row.
// Such files exist in the wild and may be produced by obfuscators.
if (standalonePdbStream.Length == 0 && this.ModuleTable.NumberOfRows < 1)
{
throw new BadImageFormatException(SR.Format(SR.ModuleTableInvalidNumberOfRows, this.ModuleTable.NumberOfRows));
}
// read
this.NamespaceCache = new NamespaceCache(this);
if (_metadataKind != MetadataKind.Ecma335)
{
this.WinMDMscorlibRef = FindMscorlibAssemblyRefNoProjection();
}
}
/// <summary>
/// Looks like this function reads beginning of the header described in
/// ECMA-335 24.2.1 Metadata root
/// </summary>
private void ReadMetadataHeader(ref BlobReader memReader, out string versionString)
{
if (memReader.RemainingBytes < COR20Constants.MinimumSizeofMetadataHeader)
{
throw new BadImageFormatException(SR.MetadataHeaderTooSmall);
}
uint signature = memReader.ReadUInt32();
if (signature != COR20Constants.COR20MetadataSignature)
{
throw new BadImageFormatException(SR.MetadataSignature);
}
// major version
memReader.ReadUInt16();
// minor version
memReader.ReadUInt16();
// reserved:
memReader.ReadUInt32();
int versionStringSize = memReader.ReadInt32();
if (memReader.RemainingBytes < versionStringSize)
{
throw new BadImageFormatException(SR.NotEnoughSpaceForVersionString);
}
int numberOfBytesRead;
versionString = memReader.GetMemoryBlockAt(0, versionStringSize).PeekUtf8NullTerminated(0, null, UTF8Decoder, out numberOfBytesRead, '\0');
memReader.SkipBytes(versionStringSize);
}
public static MethodBodyBlock Create(BlobReader reader)
{
int startOffset = reader.Offset;
int ilSize;
// Error need to check if the Memory Block is empty. This is calse for all the calls...
byte headByte = reader.ReadByte();
if ((headByte & ILFormatMask) == ILTinyFormat)
{
// tiny IL can't have locals so technically this shouldn't matter,
// but false is consistent with other metadata readers and helps
// for use cases involving comparing our output with theirs.
const bool initLocalsForTinyIL = false;
ilSize = headByte >> ILTinyFormatSizeShift;
return new MethodBodyBlock(
initLocalsForTinyIL,
8,
default(StandaloneSignatureHandle),
reader.GetMemoryBlockAt(0, ilSize),
ImmutableArray<ExceptionRegion>.Empty,
1 + ilSize // header + IL
);
}
if ((headByte & ILFormatMask) != ILFatFormat)
{
throw new BadImageFormatException(string.Format(MetadataResources.InvalidMethodHeader1, headByte));
}
// FatILFormat
byte headByte2 = reader.ReadByte();
if ((headByte2 >> ILFatFormatHeaderSizeShift) != ILFatFormatHeaderSize)
{
throw new BadImageFormatException(string.Format(MetadataResources.InvalidMethodHeader2, headByte, headByte2));
}
bool localsInitialized = (headByte & ILInitLocals) == ILInitLocals;
bool hasExceptionHandlers = (headByte & ILMoreSects) == ILMoreSects;
ushort maxStack = reader.ReadUInt16();
ilSize = reader.ReadInt32();
int localSignatureToken = reader.ReadInt32();
StandaloneSignatureHandle localSignatureHandle;
if (localSignatureToken == 0)
{
localSignatureHandle = default(StandaloneSignatureHandle);
}
else if ((localSignatureToken & TokenTypeIds.TokenTypeMask) == TokenTypeIds.Signature)
{
localSignatureHandle = StandaloneSignatureHandle.FromRowId((uint)localSignatureToken & TokenTypeIds.RIDMask);
}
else
{
throw new BadImageFormatException(string.Format(MetadataResources.InvalidLocalSignatureToken, unchecked((uint)localSignatureToken)));
}
var ilBlock = reader.GetMemoryBlockAt(0, ilSize);
reader.SkipBytes(ilSize);
ImmutableArray<ExceptionRegion> exceptionHandlers;
if (hasExceptionHandlers)
{
reader.Align(4);
byte sehHeader = reader.ReadByte();
if ((sehHeader & SectEHTable) != SectEHTable)
{
throw new BadImageFormatException(string.Format(MetadataResources.InvalidSehHeader, sehHeader));
}
bool sehFatFormat = (sehHeader & SectFatFormat) == SectFatFormat;
int dataSize = reader.ReadByte();
if (sehFatFormat)
{
dataSize += reader.ReadUInt16() << 8;
exceptionHandlers = ReadFatExceptionHandlers(ref reader, dataSize / 24);
}
else
{
reader.SkipBytes(2); // skip over reserved field
exceptionHandlers = ReadSmallExceptionHandlers(ref reader, dataSize / 12);
}
}
else
{
exceptionHandlers = ImmutableArray<ExceptionRegion>.Empty;
}
return new MethodBodyBlock(
localsInitialized,
maxStack,
localSignatureHandle,
ilBlock,
exceptionHandlers,
reader.Offset - startOffset);
}
