public void ResolveImports(ExportTable exports)
{
if (entry.size == 0)
{
Tracing.Log(Tracing.Debug, "// No imports to resolve.");
return;
}
int importOffset = (int)entry.virtualAddress;
//Tracing.Log(Tracing.Debug, " import offset={0:x8}", importOffset);
//
// start at the importOffset specified above creating and filling out ImportDescriptors
// There is no indication in the header as to how many descriptors are present.
// In the last descriptor all fields will be 0; this code checks just the firstChunk field.
//
for (;;)
{
ImportDescriptor importDescriptor =
new ImportDescriptor(mem, ref importOffset);
if (importDescriptor.firstChunk == 0)
{
return;
}
ushort hint = 0;
String name = null;
if (importDescriptor.name != 0)
{
name = mem.ReadAsciiZeroString((int)importDescriptor.name);
}
#if verbose
Tracing.Log(Tracing.Debug, "// {0}", name);
importDescriptor.DumpToStream("// ");
Tracing.Log(Tracing.Debug, "//");
#endif
UIntPtr offsetHintTable = UIntPtr.Zero;
if (0 == importDescriptor.characteristics)
{
offsetHintTable = (UIntPtr)importDescriptor.characteristics;
}
else
{
offsetHintTable = (UIntPtr)importDescriptor.firstChunk;
}
UIntPtr offsetIAT = (UIntPtr)importDescriptor.firstChunk;
#if PTR_SIZE_64
//
// AIFIX: Add hint logic.
//
for (;;)
{
ulong ImportEntry = (ulong)mem.Read64((int)offsetIAT);
if (ImportEntry == 0)
{
break;
}
if ((ImportEntry >> 63) != 0)
{
throw new BadImageFormatException("Import Ordinal encountered");
}
name = mem.ReadAsciiZeroString(((int)(ImportEntry & 0x7FFFFFFF)) + 2);
UIntPtr Address;
Address = exports.Resolve(hint, name);
if (Address == 0)
{
throw new BadImageFormatException("Import not found");
}
mem.Write64((int)offsetIAT, (ulong)Address);
offsetIAT += 8;
}
#else
for (;;)
{
// read elements in the hint array for processing
// the hint array terminates when the its content is 0
int importByNameEntry = (int)mem.Read32((int)offsetHintTable);
if (importByNameEntry == 0)
{
break;
}
#if verbose
Tracing.Log(Tracing.Debug, "importByName entry is {0:x8}",
importByNameEntry);
#endif
int nameStringOffset = importByNameEntry & 0x7fffffff;
if ((importByNameEntry & 0x8000000) != 0)
{
// should never happen in Singularity (no Ordinals)
throw new BadImageFormatException("Import Ordinal encountered");
}
else
{
name = mem.ReadAsciiZeroString((int)nameStringOffset + 2);
hint = mem.Read16Unchecked(nameStringOffset);
//Tracing.Log(Tracing.Debug, " function to lookup is {0}", name);
UIntPtr addr = exports.Resolve(hint, name);
if (0 != addr)
{
//Overwrite ptr in IAT with address of function in the
// IAT thunk table
#if verbose
int meth = name.IndexOf('@');
int rest = name.IndexOf('@', meth + 1) + 1;
int clas = name.LastIndexOf('_', rest, rest - meth) + 1;
Tracing.Log(Tracing.Debug, " import: {1:x8} is {2:x8} {0}",
name.Substring(0, meth) + "@" + name.Substring(clas, rest - clas) + "@" name.Substring(rest)
(uint) offsetIAT, (uint)addr);
#endif
mem.Write32((int)offsetIAT, (uint)addr);
}
else
{
Tracing.Log(Tracing.Debug, " Import not found: {0}", name);
throw new BadImageFormatException("Import not found");
}
}
// increment "array indices"
offsetIAT += 4;
offsetHintTable += 4;
}
//Tracing.Log(Tracing.Debug, "");
#endif
}
//throw new BadImageFormatException("");
}
public void DumpIAT(String title)
{
Tracing.Log(Tracing.Debug, "// {0}", title);
if (entry.size == 0)
{
Tracing.Log(Tracing.Debug, "// No data.");
return;
}
int importOffset = (int)entry.virtualAddress;
Tracing.Log(Tracing.Debug, " import offset={0:x8}", importOffset);
//
// start at the importOffset specified above creating and filling out ImportDescriptors
// There is no indication in the header as to how many descriptors are present.
// In the last descriptor all fields will be 0; this code checks just the firstChunk field.
//
for (;;)
{
ImportDescriptor importDescriptor =
new ImportDescriptor(mem, ref importOffset);
//Use hit/Name array pointed to by "characteristics"
// FirstChunk points to the IAT table which is modified at load time to
// to reflect the fixed-up thunk to access the function
if (importDescriptor.characteristics == 0)
{
return;
}
String name = null;
if (importDescriptor.name != 0)
{
name = mem.ReadAsciiZeroString((int)importDescriptor.name);
}
Tracing.Log(Tracing.Debug, "// {0}", name);
importDescriptor.DumpToStream();
Tracing.Log(Tracing.Debug, "//");
int importTableOffset = (int)importDescriptor.characteristics;
for (;;)
{
int importTableID = (int)mem.Read32(importTableOffset);
if (importTableID == 0)
{
break;
}
Tracing.Log(Tracing.Debug, "importTableID is {0:x8}", importTableID);
int nameStringOffset =
importTableID & 0x7fffffff;
importTableOffset += 4;
if ((importTableID & 0x8000000) != 0)
{
Tracing.Log(Tracing.Debug, "// {0:x8} by ordinal {1:x8}",
mem.Read16(importTableOffset),
(importTableID & 0x7ffffff));
}
else
{
Tracing.Log(Tracing.Debug, "// {1:x8} {0:x8}",
mem.ReadAsciiZeroString(nameStringOffset + 2),
mem.Read16(importTableOffset));
}
}
Tracing.Log(Tracing.Debug, "");
}
//throw new BadImageFormatException("");
}
private void DumpIAT(StreamWriter outputStream,
String title,
ref DirectoryEntry entry)
{
outputStream.WriteLine("// " + title);
if (entry.size == 0)
{
outputStream.WriteLine("// No data.");
outputStream.WriteLine();
return;
}
if (entry.size < ImportDescriptor.SIZE)
{
outputStream.WriteLine("Not enough data for IMAGE_IMPORT_DESCRIPTOR");
return;
}
int importOffset = this.VaToOffset(entry.virtualAddress);
while (true)
{
this.stream.Seek(importOffset, SeekOrigin.Begin);
ImportDescriptor importDescriptor =
new ImportDescriptor(this.stream);
if (importDescriptor.firstChunk == 0)
{
return;
}
String name = null;
if (importDescriptor.name != 0)
{
int nameOffset = this.VaToOffset(importDescriptor.name);
name = this.readString(nameOffset);
}
outputStream.WriteLine("// " + name);
importDescriptor.DumpToStream(outputStream, "// ");
outputStream.WriteLine("//");
int importTableOffset =
this.VaToOffset(importDescriptor.firstChunk);
while (true)
{
this.stream.Seek(importTableOffset, SeekOrigin.Begin);
BinaryReader intReader = new BinaryReader(this.stream);
int importTableID = intReader.ReadInt32();
if (importTableID == 0)
{
break;
}
outputStream.WriteLine("importTableID is " + importTableID.ToString("x"));
outputStream.Flush();
int nameStringOffset =
this.VaToOffset(importTableID & 0x7fffffff);
this.stream.Seek(nameStringOffset, SeekOrigin.Begin);
intReader = new BinaryReader(this.stream);
if ((importTableID & 0x8000000) != 0)
{
outputStream.WriteLine("// " + intReader.ReadInt16().ToString("x8") + " by ordinal " + (importTableID & 0x7ffffff));
}
else
{
outputStream.WriteLine("// " + intReader.ReadInt16().ToString("x8") + " " + this.readString(nameStringOffset + 2));
}
importTableOffset += 4;
}
outputStream.WriteLine();
importOffset += ImportDescriptor.SIZE;
}
}