public unsafe void GetReader_Offset()
{
var array = ImmutableArray.Create(new byte[] { 0, 1, 2, 3, 4 });
var provider = new ByteArrayMemoryProvider(array);
var block = provider.GetMemoryBlock();
var peBlock = new PEMemoryBlock(block, offset: 1);
var reader1 = peBlock.GetReader();
Assert.Equal(4, reader1.Length);
AssertEx.Equal(new byte[] { 1, 2, 3 }, reader1.ReadBytes(3));
AssertEx.Equal(new byte[] { 4 }, reader1.ReadBytes(1));
var reader2 = peBlock.GetReader(1, 2);
Assert.Equal(2, reader2.Length);
AssertEx.Equal(new byte[] { 2, 3 }, reader2.ReadBytes(2));
var reader3 = peBlock.GetReader(4, 0);
Assert.Equal(0, reader3.Length);
AssertEx.Equal(new byte[] { }, reader3.ReadBytes(0));
Assert.Throws<ArgumentOutOfRangeException>(() => peBlock.GetReader(0, 5));
Assert.Throws<ArgumentOutOfRangeException>(() => peBlock.GetReader(4, 1));
Assert.Throws<ArgumentOutOfRangeException>(() => peBlock.GetReader(5, 0));
}
private void ApplyRelocations(ModuleInfo module, PEReader reader, int dataVA, byte[] data)
{
PEMemoryBlock relocations = reader.GetSectionData(".reloc");
if (relocations.Length > 0)
{
ulong baseDelta = module.ImageBase - reader.PEHeaders.PEHeader.ImageBase;
Trace.TraceInformation("ApplyRelocations: dataVA {0:X8} dataCB {1} baseDelta: {2:X16}", dataVA, data.Length, baseDelta);
BlobReader blob = relocations.GetReader();
while (blob.RemainingBytes > 0)
{
// Read IMAGE_BASE_RELOCATION struct
int virtualAddress = blob.ReadInt32();
int sizeOfBlock = blob.ReadInt32();
// Each relocation block covers 4K
if (dataVA >= virtualAddress && dataVA < (virtualAddress + 4096))
{
int entryCount = (sizeOfBlock - 8) / 2; // (sizeOfBlock - sizeof(IMAGE_BASE_RELOCATION)) / sizeof(WORD)
Trace.TraceInformation("ApplyRelocations: reloc VirtualAddress {0:X8} SizeOfBlock {1:X8} entry count {2}", virtualAddress, sizeOfBlock, entryCount);
int relocsApplied = 0;
for (int e = 0; e < entryCount; e++)
{
// Read relocation type/offset
ushort entry = blob.ReadUInt16();
if (entry == 0)
{
break;
}
var type = (BaseRelocationType)(entry >> 12); // type is 4 upper bits
int relocVA = virtualAddress + (entry & 0xfff); // offset is 12 lower bits
// Is this relocation in the data?
if (relocVA >= dataVA && relocVA < (dataVA + data.Length))
{
int offset = relocVA - dataVA;
switch (type)
{
case BaseRelocationType.ImageRelBasedAbsolute:
break;
case BaseRelocationType.ImageRelBasedHighLow:
{
uint value = BitConverter.ToUInt32(data, offset);
value += (uint)baseDelta;
byte[] source = BitConverter.GetBytes(value);
Array.Copy(source, 0, data, offset, source.Length);
break;
}
case BaseRelocationType.ImageRelBasedDir64:
{
ulong value = BitConverter.ToUInt64(data, offset);
value += baseDelta;
byte[] source = BitConverter.GetBytes(value);
Array.Copy(source, 0, data, offset, source.Length);
break;
}
default:
Debug.Fail($"ApplyRelocations: invalid relocation type {type}");
break;
}
relocsApplied++;
}
}
Trace.TraceInformation("ApplyRelocations: relocs {0} applied", relocsApplied);
}
else
{
// Skip to the next relocation block
blob.Offset += sizeOfBlock - 8;
}
}
}
}
private PEExportTable(PEReader peReader)
{
_namedExportRva = new Dictionary <string, int>();
_ordinalRva = new Dictionary <int, int>();
DirectoryEntry exportTable = peReader.PEHeaders.PEHeader.ExportTableDirectory;
PEMemoryBlock peImage = peReader.GetEntireImage();
BlobReader exportTableHeader = peImage.GetReader(peReader.GetOffset(exportTable.RelativeVirtualAddress), exportTable.Size);
if (exportTableHeader.Length == 0)
{
return;
}
// +0x00: reserved
exportTableHeader.ReadUInt32();
// +0x04: TODO: time/date stamp
exportTableHeader.ReadUInt32();
// +0x08: major version
exportTableHeader.ReadUInt16();
// +0x0A: minor version
exportTableHeader.ReadUInt16();
// +0x0C: DLL name RVA
exportTableHeader.ReadUInt32();
// +0x10: ordinal base
int minOrdinal = exportTableHeader.ReadInt32();
// +0x14: number of entries in the address table
int addressEntryCount = exportTableHeader.ReadInt32();
// +0x18: number of name pointers
int namePointerCount = exportTableHeader.ReadInt32();
// +0x1C: export address table RVA
int addressTableRVA = exportTableHeader.ReadInt32();
// +0x20: name pointer RVA
int namePointerRVA = exportTableHeader.ReadInt32();
// +0x24: ordinal table RVA
int ordinalTableRVA = exportTableHeader.ReadInt32();
int[] addressTable = new int[addressEntryCount];
BlobReader addressTableReader = peImage.GetReader(peReader.GetOffset(addressTableRVA), sizeof(int) * addressEntryCount);
for (int entryIndex = 0; entryIndex < addressEntryCount; entryIndex++)
{
addressTable[entryIndex] = addressTableReader.ReadInt32();
}
ushort[] ordinalTable = new ushort[namePointerCount];
BlobReader ordinalTableReader = peImage.GetReader(peReader.GetOffset(ordinalTableRVA), sizeof(ushort) * namePointerCount);
for (int entryIndex = 0; entryIndex < namePointerCount; entryIndex++)
{
ushort ordinalIndex = ordinalTableReader.ReadUInt16();
ordinalTable[entryIndex] = ordinalIndex;
_ordinalRva.Add(entryIndex + minOrdinal, addressTable[ordinalIndex]);
}
BlobReader namePointerReader = peImage.GetReader(peReader.GetOffset(namePointerRVA), sizeof(int) * namePointerCount);
for (int entryIndex = 0; entryIndex < namePointerCount; entryIndex++)
{
int nameRVA = namePointerReader.ReadInt32();
if (nameRVA != 0)
{
int nameOffset = peReader.GetOffset(nameRVA);
BlobReader nameReader = peImage.GetReader(nameOffset, peImage.Length - nameOffset);
StringBuilder nameBuilder = new StringBuilder();
for (byte ascii; (ascii = nameReader.ReadByte()) != 0;)
{
nameBuilder.Append((char)ascii);
}
_namedExportRva.Add(nameBuilder.ToString(), addressTable[ordinalTable[entryIndex]]);
}
}
}
internal unsafe int ReadVirtualForWindows(
IntPtr self,
ulong address,
IntPtr buffer,
uint bytesRequested,
uint *pbytesRead)
{
if (DataReader.ReadMemory(address, buffer, unchecked ((int)bytesRequested), out int bytesRead))
{
Write(pbytesRead, (uint)bytesRead);
return(S_OK);
}
// The memory read failed. Check if there is a module that contains the
// address range being read and map it into the virtual address space.
foreach (ModuleInfo module in DataReader.EnumerateModules())
{
ulong start = module.ImageBase;
ulong end = start + module.FileSize;
if (start <= address && end > address)
{
Trace.TraceInformation("ReadVirtualForWindows: address {0:X16} size {1:X8} found module {2}", address, bytesRequested, module.FileName);
// We found a module that contains the memory requested. Now find or download the PE image.
PEReader reader = GetPEReader(module);
if (reader != null)
{
// Read the memory from the PE image. There are a few limitions:
// 1) Fix ups are NOT applied to the sections
// 2) Memory regions that cross/contain heap memory into module image memory
int rva = (int)(address - start);
try
{
PEMemoryBlock block = reader.GetSectionData(rva);
if (block.Pointer == null)
{
Trace.TraceInformation("ReadVirtualForWindows: rva {0:X8} not in any section; reading from entire image", rva);
// If the address isn't contained in one of the sections, assume that SOS is reader the PE headers directly.
block = reader.GetEntireImage();
}
else
{
rva = 0;
}
BlobReader blob = block.GetReader(rva, (int)bytesRequested);
byte[] data = blob.ReadBytes((int)bytesRequested);
Marshal.Copy(data, 0, buffer, data.Length);
Write(pbytesRead, (uint)data.Length);
return(S_OK);
}
catch (Exception ex) when(ex is BadImageFormatException || ex is InvalidOperationException || ex is IOException)
{
Trace.TraceError("ReadVirtualForWindows: exception {0}", ex);
}
}
break;
}
}
return(E_FAIL);
}
internal unsafe InternalManifestResourceInfo GetInternalManifestResourceInfo(string resourceName)
{
MetadataReader reader = Reader;
InternalManifestResourceInfo result = new InternalManifestResourceInfo();
ManifestResourceHandleCollection manifestResources = reader.ManifestResources;
foreach (ManifestResourceHandle resourceHandle in manifestResources)
{
ManifestResource resource = resourceHandle.GetManifestResource(reader);
if (resource.Name.Equals(resourceName, reader))
{
result.Found = true;
if (resource.Implementation.IsNil)
{
checked
{
// Embedded data resource
result.ResourceLocation = ResourceLocation.Embedded | ResourceLocation.ContainedInManifestFile;
PEReader pe = _guardedPEReader.PEReader;
PEMemoryBlock resourceDirectory = pe.GetSectionData(pe.PEHeaders.CorHeader.ResourcesDirectory.RelativeVirtualAddress);
BlobReader blobReader = resourceDirectory.GetReader((int)resource.Offset, resourceDirectory.Length - (int)resource.Offset);
uint length = blobReader.ReadUInt32();
result.PointerToResource = blobReader.CurrentPointer;
// Length check the size of the resource to ensure it fits in the PE file section, note, this is only safe as its in a checked region
if (length + sizeof(Int32) > blobReader.Length)
{
throw new BadImageFormatException();
}
result.SizeOfResource = length;
}
}
else
{
if (resource.Implementation.Kind == HandleKind.AssemblyFile)
{
// Get file name
result.ResourceLocation = default(ResourceLocation);
AssemblyFile file = ((AssemblyFileHandle)resource.Implementation).GetAssemblyFile(reader);
result.FileName = file.Name.GetString(reader);
if (file.ContainsMetadata)
{
EcmaModule module = (EcmaModule)Assembly.GetModule(result.FileName);
if (module == null)
{
throw new BadImageFormatException(SR.Format(SR.ManifestResourceInfoReferencedBadModule, result.FileName));
}
result = module.GetInternalManifestResourceInfo(resourceName);
}
}
else if (resource.Implementation.Kind == HandleKind.AssemblyReference)
{
// Resolve assembly reference
result.ResourceLocation = ResourceLocation.ContainedInAnotherAssembly;
RoAssemblyName destinationAssemblyName = ((AssemblyReferenceHandle)resource.Implementation).ToRoAssemblyName(reader);
result.ReferencedAssembly = Loader.ResolveAssembly(destinationAssemblyName);
}
}
}
}
return(result);
}
internal unsafe static MetadataReader ToMetadataReader(this PEMemoryBlock metadata)
{
return(new MetadataReader(metadata.Pointer, metadata.Length, MetadataReaderOptions.None));
}
internal unsafe ImportedModule(PEMemoryBlock metadataBlock)
{
_reader = new MetadataReader(metadataBlock.Pointer, metadataBlock.Length);
}
/// <summary>
/// Read memory from a PE module for the memory cache. Finds locally or downloads a module
/// and "maps" it into the address space. This function can return more than requested which
/// means the block should not be cached.
/// </summary>
/// <param name="address">memory address</param>
/// <param name="bytesRequested">number of bytes</param>
/// <returns>bytes read or null if error</returns>
private byte[] ReadMemoryFromModule(ulong address, int bytesRequested)
{
Debug.Assert((address & ~_memoryService.SignExtensionMask()) == 0);
IModule module = _moduleService.GetModuleFromAddress(address);
if (module != null)
{
// Recursion can happen in the case where the PE, ELF or MachO headers (in the module.Services.GetService<>() calls)
// used to get the timestamp/filesize or build id are not in the dump.
if (!_recursionProtection.Contains(address))
{
_recursionProtection.Add(address);
try
{
// We found a module that contains the memory requested. Now find or download the PE image.
PEReader reader = module.Services.GetService <PEReader>();
if (reader is not null)
{
int rva = (int)(address - module.ImageBase);
Debug.Assert(rva >= 0);
Debug.Assert(!reader.IsLoadedImage);
Debug.Assert(reader.IsEntireImageAvailable);
#if TRACE_VERBOSE
Trace.TraceInformation($"ReadMemoryFromModule: address {address:X16} rva {rva:X8} bytesRequested {bytesRequested:X8} {module.FileName}");
#endif
// Not reading anything in the PE's header
if (rva > reader.PEHeaders.PEHeader.SizeOfHeaders)
{
// This property can cause recursion because this PE being mapped here is read to determine the layout
if (!module.IsFileLayout.GetValueOrDefault(true))
{
// If the PE image that we are mapping into has the "loaded" layout convert the rva to a flat/file based one.
for (int i = 0; i < reader.PEHeaders.SectionHeaders.Length; i++)
{
SectionHeader section = reader.PEHeaders.SectionHeaders[i];
if (rva >= section.VirtualAddress && rva < (section.VirtualAddress + section.VirtualSize))
{
rva = section.PointerToRawData + (rva - section.VirtualAddress);
break;
}
}
}
}
try
{
byte[] data = null;
// Read the memory from the PE image found/downloaded above
PEMemoryBlock block = reader.GetEntireImage();
if (rva < block.Length)
{
int size = Math.Min(block.Length - rva, bytesRequested);
if ((rva + size) <= block.Length)
{
data = block.GetReader(rva, size).ReadBytes(size);
ApplyRelocations(module, reader, (int)(address - module.ImageBase), data);
}
else
{
Trace.TraceError($"ReadMemoryFromModule: FAILED address {address:X16} rva {rva:X8} {module.FileName}");
}
}
return(data);
}
catch (Exception ex) when(ex is BadImageFormatException || ex is InvalidOperationException || ex is IOException)
{
Trace.TraceError($"ReadMemoryFromModule: exception: address {address:X16} {ex.Message} {module.FileName}");
}
}
else
{
// Find or download the ELF image, if one.
Reader virtualAddressReader = module.Services.GetService <ELFFile>()?.VirtualAddressReader;
if (virtualAddressReader is null)
{
// Find or download the MachO image, if one.
virtualAddressReader = module.Services.GetService <MachOFile>()?.VirtualAddressReader;
}
if (virtualAddressReader is not null)
{
// Read the memory from the image.
ulong rva = address - module.ImageBase;
Debug.Assert(rva >= 0);
try
{
#if TRACE_VERBOSE
Trace.TraceInformation($"ReadMemoryFromModule: address {address:X16} rva {rva:X16} size {bytesRequested:X8} in ELF or MachO file {module.FileName}");
#endif
byte[] data = new byte[bytesRequested];
uint read = virtualAddressReader.Read(rva, data, 0, (uint)bytesRequested);
if (read == 0)
{
Trace.TraceError($"ReadMemoryFromModule: FAILED address {address:X16} rva {rva:X16} {module.FileName}");
data = null;
}
return(data);
}
catch (Exception ex) when(ex is BadInputFormatException || ex is InvalidVirtualAddressException)
{
Trace.TraceError($"ReadMemoryFromModule: ELF or MachO file exception: address {address:X16} {ex.Message} {module.FileName}");
}
}
}
}
finally
{
_recursionProtection.Remove(address);
}
}
else
{
Trace.TraceError($"ReadMemoryFromModule: recursion: address {address:X16} size {bytesRequested:X8} {module.FileName}");
}
}
return(null);
}
public unsafe void GetContent_Offset()
{
var array = ImmutableArray.Create(new byte[] { 0, 1, 2, 3, 4 });
var provider = new ByteArrayMemoryProvider(array);
var block = provider.GetMemoryBlock();
var peBlock = new PEMemoryBlock(block, offset: 1);
AssertEx.Equal(new byte[] { 1, 2, 3, 4 }, peBlock.GetContent());
AssertEx.Equal(new byte[] { 2, 3 }, peBlock.GetContent(1, 2));
AssertEx.Equal(new byte[] { }, peBlock.GetContent(4, 0));
Assert.Throws<ArgumentOutOfRangeException>(() => peBlock.GetContent(0, 5));
Assert.Throws<ArgumentOutOfRangeException>(() => peBlock.GetContent(4, 1));
Assert.Throws<ArgumentOutOfRangeException>(() => peBlock.GetContent(5, 0));
}