private void CreateSection(ModuleWriter writer)
{
// move some PE parts to separate section to prevent it from being hashed
var peSection = new PESection("", 0x60000020);
bool moved = false;
uint alignment;
if (writer.StrongNameSignature != null) {
alignment = writer.TextSection.Remove(writer.StrongNameSignature).Value;
peSection.Add(writer.StrongNameSignature, alignment);
moved = true;
}
if (writer.ImportAddressTable != null) {
alignment = writer.TextSection.Remove(writer.ImportAddressTable).Value;
peSection.Add(writer.ImportAddressTable, alignment);
moved = true;
}
if (writer.StartupStub != null) {
alignment = writer.TextSection.Remove(writer.StartupStub).Value;
peSection.Add(writer.StartupStub, alignment);
moved = true;
}
if (moved)
writer.Sections.Add(peSection);
// create section
var nameBuffer = new byte[8];
nameBuffer[0] = (byte)(name1 >> 0);
nameBuffer[1] = (byte)(name1 >> 8);
nameBuffer[2] = (byte)(name1 >> 16);
nameBuffer[3] = (byte)(name1 >> 24);
nameBuffer[4] = (byte)(name2 >> 0);
nameBuffer[5] = (byte)(name2 >> 8);
nameBuffer[6] = (byte)(name2 >> 16);
nameBuffer[7] = (byte)(name2 >> 24);
var newSection = new PESection(Encoding.ASCII.GetString(nameBuffer), 0xE0000040);
writer.Sections.Insert(random.NextInt32(writer.Sections.Count), newSection);
// random padding at beginning to prevent revealing hash key
newSection.Add(new ByteArrayChunk(random.NextBytes(0x10)), 0x10);
// create index
var bodyIndex = new JITBodyIndex(methods.Select(method => writer.MetaData.GetToken(method).Raw));
newSection.Add(bodyIndex, 0x10);
// move initialization away from module initializer
cctorRepl.Body = cctor.Body;
cctor.Body = new CilBody();
cctor.Body.Instructions.Add(Instruction.Create(OpCodes.Call, initMethod));
cctor.Body.Instructions.Add(Instruction.Create(OpCodes.Call, cctorRepl));
cctor.Body.Instructions.Add(Instruction.Create(OpCodes.Ret));
// save methods
foreach (MethodDef method in methods.WithProgress(context.Logger)) {
if (!method.HasBody)
continue;
MDToken token = writer.MetaData.GetToken(method);
var jitBody = new JITMethodBody();
var bodyWriter = new JITMethodBodyWriter(writer.MetaData, method.Body, jitBody, random.NextUInt32(), writer.MetaData.KeepOldMaxStack || method.Body.KeepOldMaxStack);
bodyWriter.Write();
jitBody.Serialize(token.Raw, key, fieldLayout);
bodyIndex.Add(token.Raw, jitBody);
method.Body = NopBody;
writer.MetaData.TablesHeap.MethodTable[token.Rid].ImplFlags |= (ushort)MethodImplAttributes.NoInlining;
context.CheckCancellation();
}
bodyIndex.PopulateSection(newSection);
// padding to prevent bad size due to shift division
newSection.Add(new ByteArrayChunk(new byte[4]), 4);
}
private void EncryptSection(ModuleWriter writer)
{
Stream stream = writer.DestinationStream;
var reader = new BinaryReader(writer.DestinationStream);
stream.Position = 0x3C;
stream.Position = reader.ReadUInt32();
stream.Position += 6;
ushort sections = reader.ReadUInt16();
stream.Position += 0xc;
ushort optSize = reader.ReadUInt16();
stream.Position += 2 + optSize;
uint encLoc = 0, encSize = 0;
for (int i = 0; i < sections; i++) {
uint nameHash = reader.ReadUInt32() * reader.ReadUInt32();
stream.Position += 8;
if (nameHash == name1 * name2) {
encSize = reader.ReadUInt32();
encLoc = reader.ReadUInt32();
}
else if (nameHash != 0) {
uint sectSize = reader.ReadUInt32();
uint sectLoc = reader.ReadUInt32();
Hash(stream, reader, sectLoc, sectSize);
}
stream.Position += 16;
}
uint[] key = DeriveKey();
encSize >>= 2;
stream.Position = encLoc;
var result = new uint[encSize];
for (uint i = 0; i < encSize; i++) {
uint data = reader.ReadUInt32();
result[i] = data ^ key[i & 0xf];
key[i & 0xf] = (key[i & 0xf] ^ data) + 0x3dbb2819;
}
var byteResult = new byte[encSize << 2];
Buffer.BlockCopy(result, 0, byteResult, 0, byteResult.Length);
stream.Position = encLoc;
stream.Write(byteResult, 0, byteResult.Length);
}
private void CreateSections(ModuleWriter writer)
{
var nameBuffer = new byte[8];
nameBuffer[0] = (byte)(name1 >> 0);
nameBuffer[1] = (byte)(name1 >> 8);
nameBuffer[2] = (byte)(name1 >> 16);
nameBuffer[3] = (byte)(name1 >> 24);
nameBuffer[4] = (byte)(name2 >> 0);
nameBuffer[5] = (byte)(name2 >> 8);
nameBuffer[6] = (byte)(name2 >> 16);
nameBuffer[7] = (byte)(name2 >> 24);
var newSection = new PESection(Encoding.ASCII.GetString(nameBuffer), 0xE0000040);
writer.Sections.Insert(0, newSection); // insert first to ensure proper RVA
uint alignment;
alignment = writer.TextSection.Remove(writer.MetaData).Value;
writer.TextSection.Add(writer.MetaData, alignment);
alignment = writer.TextSection.Remove(writer.NetResources).Value;
writer.TextSection.Add(writer.NetResources, alignment);
alignment = writer.TextSection.Remove(writer.Constants).Value;
newSection.Add(writer.Constants, alignment);
// move some PE parts to separate section to prevent it from being hashed
var peSection = new PESection("", 0x60000020);
bool moved = false;
if (writer.StrongNameSignature != null) {
alignment = writer.TextSection.Remove(writer.StrongNameSignature).Value;
peSection.Add(writer.StrongNameSignature, alignment);
moved = true;
}
if (writer.ImportAddressTable != null) {
alignment = writer.TextSection.Remove(writer.ImportAddressTable).Value;
peSection.Add(writer.ImportAddressTable, alignment);
moved = true;
}
if (writer.StartupStub != null) {
alignment = writer.TextSection.Remove(writer.StartupStub).Value;
peSection.Add(writer.StartupStub, alignment);
moved = true;
}
if (moved)
writer.Sections.Add(peSection);
// move encrypted methods
var encryptedChunk = new MethodBodyChunks(writer.TheOptions.ShareMethodBodies);
newSection.Add(encryptedChunk, 4);
foreach (MethodDef method in methods) {
if (!method.HasBody)
continue;
MethodBody body = writer.MetaData.GetMethodBody(method);
bool ok = writer.MethodBodies.Remove(body);
encryptedChunk.Add(body);
}
// padding to prevent bad size due to shift division
newSection.Add(new ByteArrayChunk(new byte[4]), 4);
}