//Construct the binary assembly instance
public PEFile(string fileName)
{
this.FileName = fileName;
//Open the assembly's binary file in shared-read mode and copy it into a buffer so we can close the file post haste.
FileStream fileStream = new FileStream(fileName, FileMode.Open, FileAccess.Read, FileShare.Read);
byte[] streamBuffer = new byte[fileStream.Length];
fileStream.Read(streamBuffer, 0, (int)fileStream.Length);
fileStream.Close();
//Push the buffer into a memory stream and then access it through a binary reader
this.streamReader = new BinaryReader(new MemoryStream(streamBuffer));
// The rest of the code moves through the loaded assemebly as follows:
// 1) DOS header points to the PE header.
// 2) PE header contains a the CLI directory that points to the The CLI header.
// 3) In order to work out the RVAs, we need the "Sections" of the file.
// 4) CLI header in turn contains the RVA to MetaData directory.
// 5) Metadata header points to the metadata root.
// 6) metadata root lists the metadata stream headers.
// 7) metadata stream headers contain the offsets to the metadata stream. Hooray!
// We only need certain elements of the file. Those elements we
// need are stored in structs/classes, the elements we don't need
// are parsed by methods whose purpose is:
// a) to move the stream position to where we need it,
// b) to be substituted with classes as the scope of requirements increases.
ParseMsDosHeader(this.streamReader);
this.peFileHeader = new PEFileHeader(this.streamReader);
ParsePeOptionalHeader(this.streamReader);
BuildSections(this.streamReader);
// Now we have the sections we can work out where RVAs lie,
// so we can get the CLI Header, which in turn allows us to get the
// metadata directory.
ParseCliHeader(this.streamReader);
this.metaDataDirectory = new Directory(this.streamReader);
this.streamReader.BaseStream.Position = GetOffsetFromRVA(this.metaDataDirectory.Rva);
this.metaDataRoot = new MetaDataRoot(this.streamReader);
// now we have the metadataroot complete with the metadata stream headers,
// we can build the metadata streams.
BuildMetaDataStreams(this.streamReader);
// the following builds the descriptive structure found at the start of the #~ stream
// first off, move to the correct point in the file as the previous step will have left
// us in the wrong place
this.streamReader.BaseStream.Position = this.tablesStream.StartPositionInFile;
this.tablesHeader = new TablesHeader(this.streamReader, this.stringHeap);
// now we have the tables header, we can build the tables
this.tables = new Tables(this.tablesHeader, this.stringHeap, this.streamReader);
}
public Tables(TablesHeader tablesHeader, MetaDataStream stringHeap, BinaryReader reader)
{
this.tablesHeader = tablesHeader;
this.stringHeap = stringHeap;
this.reader = reader;
this.indexSizeIndicator = tablesHeader.HeapSizes;
this.RowsPerTable = tablesHeader.NumberOfRows;
// set up a table of coded index information
// the first figure in the array is the number of bits needed to encode
// which table the index is pointing to. Note, some indexes use more bits
// than are necessary, for example CustomAttributeType uses 3 bits even though
// it only points to 2 tables, so in theory could be encoded in 1 bit.
this.CodedIndexInformation = new object[12];
CodedIndexInformation[(int)Tables.CodedIndexType.TypeDefOrRef] = new int[] { 2, (int)Tables.TableName.TypeDef, (int)Tables.TableName.TypeRef, (int)Tables.TableName.TypeSpec };
CodedIndexInformation[(int)Tables.CodedIndexType.HasConstant] = new int[] { 2, (int)Tables.TableName.Field, (int)Tables.TableName.Param, (int)Tables.TableName.Property };
CodedIndexInformation[(int)Tables.CodedIndexType.HasCustomAttribute] = new int[] { 5, (int)Tables.TableName.MethodDef,
(int)Tables.TableName.Field,
(int)Tables.TableName.TypeRef,
(int)Tables.TableName.TypeDef,
(int)Tables.TableName.Param,
(int)Tables.TableName.InterfaceImpl,
(int)Tables.TableName.MemberRef,
(int)Tables.TableName.Module,
(int)Tables.TableName.DeclSecurity,
(int)Tables.TableName.Property,
(int)Tables.TableName.EventX,
(int)Tables.TableName.StandAloneSig,
(int)Tables.TableName.ModuleRef,
(int)Tables.TableName.TypeSpec,
(int)Tables.TableName.Assembly,
(int)Tables.TableName.AssemblyRef,
(int)Tables.TableName.File,
(int)Tables.TableName.ExportedType,
(int)Tables.TableName.ManifestResource };
CodedIndexInformation[(int)Tables.CodedIndexType.HasFieldMarshal] = new int[] { 1, (int)Tables.TableName.Field, (int)Tables.TableName.Param };
CodedIndexInformation[(int)Tables.CodedIndexType.HasDeclSecurity] = new int[] { 2, (int)Tables.TableName.TypeDef, (int)Tables.TableName.MethodDef, (int)Tables.TableName.Assembly };
CodedIndexInformation[(int)Tables.CodedIndexType.MemberRefParent] = new int[] { 3, (int)Tables.TableName.TypeRef, (int)Tables.TableName.ModuleRef, (int)Tables.TableName.MethodDef, (int)Tables.TableName.TypeSpec };
CodedIndexInformation[(int)Tables.CodedIndexType.HasSemantics] = new int[] { 1, (int)Tables.TableName.EventX, (int)Tables.TableName.Property };
CodedIndexInformation[(int)Tables.CodedIndexType.MethodDefOrRef] = new int[] { 1, (int)Tables.TableName.MethodDef, (int)Tables.TableName.MemberRef };
CodedIndexInformation[(int)Tables.CodedIndexType.MemberForwarded] = new int[] { 1, (int)Tables.TableName.Field, (int)Tables.TableName.MethodDef };
CodedIndexInformation[(int)Tables.CodedIndexType.Implementation] = new int[] { 2, (int)Tables.TableName.File, (int)Tables.TableName.AssemblyRef, (int)Tables.TableName.ExportedType };
CodedIndexInformation[(int)Tables.CodedIndexType.CustomAttributeType] = new int[] { 3, (int)Tables.TableName.MethodDef, (int)Tables.TableName.MemberRef };
CodedIndexInformation[(int)Tables.CodedIndexType.ResolutionScope] = new int[] { 2, (int)Tables.TableName.Module, (int)Tables.TableName.ModuleRef, (int)Tables.TableName.AssemblyRef, (int)Tables.TableName.TypeRef };
this.Module = new Module(Tables.TableName.Module, this);
this.TypeRef = new TypeRef(Tables.TableName.TypeRef, this);
this.TypeDef = new TypeDef(Tables.TableName.TypeDef, this);
this.Field = new Field(Tables.TableName.Field, this);
this.MethodDef = new MethodDef(Tables.TableName.MethodDef, this);
this.Param = new Param(Tables.TableName.Param, this);
this.InterfaceImpl = new InterfaceImpl(Tables.TableName.InterfaceImpl, this);
this.MemberRef = new MemberRef(Tables.TableName.MemberRef, this);
this.Constant = new Constant(Tables.TableName.Constant, this);
this.CustomAttribute = new CustomAttribute(Tables.TableName.CustomAttribute, this);
this.FieldMarshal = new FieldMarshal(Tables.TableName.FieldMarshal, this);
this.DeclSecurity = new DeclSecurity(Tables.TableName.DeclSecurity, this);
this.ClassLayout = new ClassLayout(Tables.TableName.ClassLayout, this);
this.FieldLayout = new FieldLayout(Tables.TableName.FieldLayout, this);
this.StandAloneSig = new StandAloneSig(Tables.TableName.StandAloneSig, this);
this.EventMap = new EventMap(Tables.TableName.EventMap, this);
this.EventX = new EventX(Tables.TableName.EventX, this);
this.PropertyMap = new PropertyMap(Tables.TableName.PropertyMap, this);
this.Property = new Property(Tables.TableName.Property, this);
this.MethodSemantics = new MethodSemantics(Tables.TableName.MethodSemantics, this);
this.MethodImpl = new MethodImpl(Tables.TableName.MethodImpl, this);
this.ModuleRef = new ModuleRef(Tables.TableName.ModuleRef, this);
this.TypeSpec = new TypeSpec(Tables.TableName.TypeSpec, this);
this.ImplMap = new ImplMap(Tables.TableName.ImplMap, this);
}
