public static ExceptionHandler FromReader(CilMethodBody cilMethodBody, IBinaryStreamReader reader, bool fatFormat)
{
var offset = reader.Position;
var handerType = fatFormat ? reader.ReadUInt32() : reader.ReadUInt16();
var tryOffset = fatFormat ? reader.ReadInt32() : reader.ReadUInt16();
var tryLength = fatFormat ? reader.ReadInt32() : reader.ReadByte();
var handlerOffset = fatFormat ? reader.ReadInt32() : reader.ReadUInt16();
var handlerLength = fatFormat ? reader.ReadInt32() : reader.ReadByte();
var classTokenOrFilterOffset = reader.ReadUInt32();
var handler = new ExceptionHandler((ExceptionHandlerType)handerType)
{
IsFat = fatFormat,
TryStart = cilMethodBody.GetInstructionByOffset(tryOffset),
TryEnd = cilMethodBody.GetInstructionByOffset(tryOffset + tryLength),
HandlerStart = cilMethodBody.GetInstructionByOffset(handlerOffset),
HandlerEnd = cilMethodBody.GetInstructionByOffset(handlerOffset + handlerLength),
};
switch (handler.HandlerType)
{
case ExceptionHandlerType.Exception:
handler.CatchType = (ITypeDefOrRef)((IOperandResolver)cilMethodBody).ResolveMember(new MetadataToken(classTokenOrFilterOffset));
break;
case ExceptionHandlerType.Filter:
handler.FilterStart = cilMethodBody.GetInstructionByOffset((int)classTokenOrFilterOffset);
break;
}
return(handler);
}
public StackInbalanceException(CilMethodBody body, int offset)
: base(string.Format("Stack inbalance was detected at offset {0:X4} in method body of {1}", offset,
body.Method))
{
Body = body;
Offset = offset;
}
/// <summary>
/// Interprets a raw method body to a CILMethodBody, disassembling all instructions, obtaining the local variables
/// and reading the extra sections for exception handlers.
/// </summary>
/// <param name="method">The parent method the method body is associated to.</param>
/// <param name="rawMethodBody">The raw method body to convert.</param>
/// <returns>The converted method body.</returns>
public static CilMethodBody FromRawMethodBody(MethodDefinition method, CilRawMethodBody rawMethodBody)
{
var body = new CilMethodBody(method);
var fatBody = rawMethodBody as CilRawFatMethodBody;
if (fatBody != null)
{
// Read fat method body header fields.
body.MaxStack = fatBody.MaxStack;
body.InitLocals = fatBody.InitLocals;
if (method.Image.TryResolveMember(new MetadataToken(fatBody.LocalVarSigToken), out var signature))
{
body.Signature = signature as StandAloneSignature;
}
}
else
{
// Set values for tiny method bodies.
body.MaxStack = 8;
body.InitLocals = false;
}
// Read code.
var codeReader = new MemoryStreamReader(rawMethodBody.Code);
var disassembler = new CilDisassembler(codeReader, body);
foreach (var instruction in disassembler.Disassemble())
{
body.Instructions.Add(instruction);
}
if (fatBody != null)
{
// Read exception handlers.
foreach (var section in fatBody.ExtraSections)
{
var sectionReader = new MemoryStreamReader(section.Data);
while (sectionReader.CanRead(section.IsFat
? ExceptionHandler.FatExceptionHandlerSize
: ExceptionHandler.SmallExceptionHandlerSize))
{
body.ExceptionHandlers.Add(ExceptionHandler.FromReader(body, sectionReader, section.IsFat));
}
}
}
return(body);
}
/// <summary>
/// Determines the amount of values pushed onto the stack by this instruction.
/// </summary>
/// <param name="parent">The parent method body the instruction is residing in.</param>
/// <returns>A non-negative number representing the amount of values pushed onto the stack.</returns>
public int GetStackPushCount(CilMethodBody parent)
{
MethodSignature signature = null;
var member = Operand as ICallableMemberReference;
var standalone = Operand as StandAloneSignature;
if (member != null)
{
signature = member.Signature as MethodSignature;
}
else if (standalone != null)
{
signature = standalone.Signature as MethodSignature;
}
switch (OpCode.StackBehaviourPush)
{
case CilStackBehaviour.Push1:
case CilStackBehaviour.Pushi:
case CilStackBehaviour.Pushi8:
case CilStackBehaviour.Pushr4:
case CilStackBehaviour.Pushr8:
case CilStackBehaviour.Pushref:
return(1);
case CilStackBehaviour.Push1_push1:
return(2);
case CilStackBehaviour.Varpush:
if (signature != null &&
(!signature.ReturnType.IsTypeOf("System", "Void") || OpCode.Code == CilCode.Newobj))
{
return(1);
}
break;
}
return(0);
}
public static CilMethodBody FromRawMethodBody(MethodDefinition method, CilRawMethodBody rawMethodBody)
{
var body = new CilMethodBody(method);
var fatBody = rawMethodBody as CilRawFatMethodBody;
if (fatBody != null)
{
body.MaxStack = fatBody.MaxStack;
body.InitLocals = fatBody.InitLocals;
IMetadataMember signature;
if (method.Image.TryResolveMember(new MetadataToken(fatBody.LocalVarSigToken), out signature))
{
body.Signature = signature as StandAloneSignature;
}
}
var codeReader = new MemoryStreamReader(rawMethodBody.Code);
var disassembler = new CilDisassembler(codeReader, body);
foreach (var instruction in disassembler.Disassemble())
{
body.Instructions.Add(instruction);
}
if (fatBody != null)
{
foreach (var section in fatBody.ExtraSections)
{
var sectionReader = new MemoryStreamReader(section.Data);
body.ExceptionHandlers.Add(ExceptionHandler.FromReader(body, sectionReader, section.IsFat));
}
}
return(body);
}
public DefaultOperandBuilder(CilMethodBody methodBody, MetadataBuffer buffer)
{
_methodBody = methodBody;
_buffer = buffer;
}
public int GetStackDelta(CilMethodBody parent)
{
int delta = 0;
MethodSignature signature = null;
var member = Operand as IMethodDefOrRef;
var standalone = Operand as StandAloneSignature;
if (member != null)
{
signature = (MethodSignature)member.Signature;
}
else if (standalone != null)
{
signature = (MethodSignature)standalone.Signature;
}
switch (OpCode.StackBehaviourPop)
{
case CilStackBehaviour.Pop1:
case CilStackBehaviour.Popi:
case CilStackBehaviour.Popref:
delta = -1;
break;
case CilStackBehaviour.Pop1_pop1:
case CilStackBehaviour.Popi_pop1:
case CilStackBehaviour.Popi_popi:
case CilStackBehaviour.Popi_popi8:
case CilStackBehaviour.Popi_popr4:
case CilStackBehaviour.Popi_popr8:
case CilStackBehaviour.Popref_pop1:
case CilStackBehaviour.Popref_popi:
delta = -2;
break;
case CilStackBehaviour.Popi_popi_popi:
case CilStackBehaviour.Popref_popi_popi:
case CilStackBehaviour.Popref_popi_popi8:
case CilStackBehaviour.Popref_popi_popr4:
case CilStackBehaviour.Popref_popi_popr8:
case CilStackBehaviour.Popref_popi_popref:
delta = -3;
break;
case CilStackBehaviour.Varpop:
if (signature == null)
{
if (OpCode.Code == CilCode.Ret)
{
delta = parent.Method.Signature.ReturnType.IsTypeOf("System", "Void") ? 0 : -1;
}
else
{
throw new ArgumentException("Invalid or unsupported operand.");
}
}
else
{
delta = -signature.Parameters.Count;
if (signature.HasThis)
{
delta--;
}
}
break;
}
switch (OpCode.StackBehaviourPush)
{
case CilStackBehaviour.Push1:
case CilStackBehaviour.Pushi:
case CilStackBehaviour.Pushi8:
case CilStackBehaviour.Pushr4:
case CilStackBehaviour.Pushr8:
case CilStackBehaviour.Pushref:
delta++;
break;
case CilStackBehaviour.Push1_push1:
delta += 2;
break;
case CilStackBehaviour.Varpush:
if (signature == null)
{
throw new ArgumentException("Invalid or unsupported operand.");
}
if (!signature.ReturnType.IsTypeOf("System", "Void"))
{
delta++;
}
break;
case CilStackBehaviour.Popref_popi_pop1:
delta += 3;
break;
}
return(delta);
}
public CilInstructionFormatter(CilMethodBody methodBody)
{
_methodBody = methodBody ?? throw new ArgumentNullException(nameof(methodBody));
}
public CilInstructionCollection(CilMethodBody body)
{
_body = body ?? throw new ArgumentNullException(nameof(body));
}
/// <summary>
/// Determines the stack delta of the instruction. That is, the amount of values pushed onto the stack
/// subtracted from the amount of values popped from the stack.
/// </summary>
/// <param name="parent">The parent method body the instruction is residing in.</param>
/// <returns>A number representing the stack delta.</returns>
public int GetStackDelta(CilMethodBody parent)
{
return(GetStackPushCount(parent) - GetStackPopCount(parent));
}
/// <summary>
/// Determines the amount of values popped from the stack by this instruction.
/// </summary>
/// <param name="parent">The parent method body the instruction is residing in.</param>
/// <returns>A non-negative number representing the amount of values popped from the stack.</returns>
public int GetStackPopCount(CilMethodBody parent)
{
MethodSignature signature = null;
var member = Operand as ICallableMemberReference;
var standalone = Operand as StandAloneSignature;
if (member != null)
{
signature = member.Signature as MethodSignature;
}
else if (standalone != null)
{
signature = standalone.Signature as MethodSignature;
}
switch (OpCode.StackBehaviourPop)
{
case CilStackBehaviour.Pop1:
case CilStackBehaviour.Popi:
case CilStackBehaviour.Popref:
return(1);
case CilStackBehaviour.Pop1_pop1:
case CilStackBehaviour.Popi_pop1:
case CilStackBehaviour.Popi_popi:
case CilStackBehaviour.Popi_popi8:
case CilStackBehaviour.Popi_popr4:
case CilStackBehaviour.Popi_popr8:
case CilStackBehaviour.Popref_pop1:
case CilStackBehaviour.Popref_popi:
return(2);
case CilStackBehaviour.Popi_popi_popi:
case CilStackBehaviour.Popref_popi_pop1:
case CilStackBehaviour.Popref_popi_popi:
case CilStackBehaviour.Popref_popi_popi8:
case CilStackBehaviour.Popref_popi_popr4:
case CilStackBehaviour.Popref_popi_popr8:
case CilStackBehaviour.Popref_popi_popref:
return(3);
case CilStackBehaviour.Varpop:
if (signature == null)
{
if (OpCode.Code == CilCode.Ret)
{
return(parent.Method.Signature.ReturnType.IsTypeOf("System", "Void") ? 0 : 1);
}
}
else
{
int count = signature.Parameters.Count;
if (signature.HasThis && OpCode.Code != CilCode.Newobj)
{
count++;
}
return(count);
}
break;
}
return(0);
}
