protected void PatchBody(Abc46 abc, MethodBodyInfo body, int bodyId)
{
AVM2Command command;
AVM2Command inlineCommand;
Dictionary <string, Label> labels = new Dictionary <string, Label>();
ArrayList instructions = new ArrayList();
Label label;
string labelId;
byte[] il = body.Code;
uint i = 0;
uint n = (uint)il.Length;
uint addr;
string name;
bool hasManualMaxStack = false;
uint manualMaxStackValue = 0;
bool patchBody = false;
//bool parseInline = false;
_labelUtil.Clear();
//
// We will convert the bytecode into a format that the As3c compiler can understand.
// When converting labels we will use a ':' in front of them instead of a '.' char for
// the ones "defined" by the ASC so that we have unique names (label syntax is .label)
//
while (i < n)
{
addr = i;
if (_labelUtil.IsMarked(addr))
{
labelId = String.Format(":{0}:", _labelUtil.GetLabelAt(addr).id);
label = new Label(labelId);
labels.Add(labelId, label);
instructions.Add(label);
}
command = Translator.ToCommand(il[i++]);
if (null == command)
{
throw new Exception("Unknown opcode detected.");
}
i += command.ReadParameters(il, i);
switch (command.OpCode)
{
case (byte)Op.Label:
labelId = String.Format(":{0}:", _labelUtil.GetLabelAt(addr).id);
label = new Label(labelId);
labels.Add(labelId, label);
instructions.Add(label);
break;
case (byte)Op.IfEqual:
case (byte)Op.IfFalse:
case (byte)Op.IfGreaterEqual:
case (byte)Op.IfGreaterThan:
case (byte)Op.IfLessEqual:
case (byte)Op.IfLowerThan:
case (byte)Op.IfNotEqual:
case (byte)Op.IfNotGreaterEqual:
case (byte)Op.IfNotGreaterThan:
case (byte)Op.IfNotLowerEqual:
case (byte)Op.IfNotLowerThan:
case (byte)Op.IfStrictEqual:
case (byte)Op.IfStrictNotEqual:
case (byte)Op.IfTrue:
case (byte)Op.Jump:
// Convert label offset to label reference ...
S24 offset = (S24)command.Parameters[0];
command.Parameters[0] = String.Format(":{0}:", _labelUtil.GetLabelAt((uint)(addr + 1 + offset.Length + offset.Value)).id);
instructions.Add(command);
break;
case (byte)Op.GetLex:
name = NameUtil.ResolveMultiname(abc, (MultinameInfo)(abc.ConstantPool.MultinameTable[(int)((U30)command.Parameters[0]).Value]));
//Console.WriteLine("Called GetLex {0}", name);
instructions.Add(command);
break;
case (byte)Op.FindPropertyStrict:
name = NameUtil.ResolveMultiname(abc, (MultinameInfo)(abc.ConstantPool.MultinameTable[(int)((U30)command.Parameters[0]).Value]));
#region INLINE Block
if (inlineWrapper == name)
{
bool parse = true;
patchBody = true;
#if DEBUG
Console.WriteLine("[i] Parsing inline block in method {0}", body.Method.Value);
#endif
while (parse && i < n)
{
inlineCommand = Translator.ToCommand(il[i++]);
if (null == inlineCommand)
{
throw new Exception("Unknown opcode detected.");
}
i += inlineCommand.ReadParameters(il, i);
switch (inlineCommand.OpCode)
{
//
// Debug instructions are kept even if they are in an inline block
//
case (byte)Op.Debug:
case (byte)Op.DebugFile:
case (byte)Op.DebugLine:
instructions.Add(inlineCommand);
break;
//
// Strings are treated as labels -- but make sure it is actually one!
//
case (byte)Op.PushString:
labelId = ((StringInfo)abc.ConstantPool.StringTable[(int)((U30)inlineCommand.Parameters[0])]).ToString();
if (labelId.IndexOf('.') != 0 || labelId.IndexOf(':') != (labelId.Length - 1))
{
throw new Exception(String.Format("Invalid string \"{0}\" in an inline block. Labels have the format \".labelName:\"", labelId));
}
labelId = labelId.Substring(0, labelId.Length - 1);
label = new Label(labelId);
labels.Add(labelId, label);
instructions.Add(label);
break;
//
// GetLex is the one that will bring public::de.popforge.asm::Op on the stack
//
case (byte)Op.GetLex:
name = NameUtil.ResolveMultiname(abc, (MultinameInfo)(abc.ConstantPool.MultinameTable[(int)((U30)inlineCommand.Parameters[0]).Value]));
if (inlineKeyword != name)
{
throw new Exception("Malformed inline block. GetLex call with invalid parameters");
}
List <AVM2Command> args = new List <AVM2Command>();
AVM2Command userCommand = null;
uint argc;
while (i < n)
{
AVM2Command arg = Translator.ToCommand(il[i++]);
if (null == arg)
{
throw new Exception("Unknown opcode detected.");
}
i += arg.ReadParameters(il, i);
if ((byte)Op.CallProperty == arg.OpCode)
{
name = NameUtil.ResolveMultiname(abc, (MultinameInfo)(abc.ConstantPool.MultinameTable[(int)((U30)arg.Parameters[0]).Value]));
userCommand = Translator.ToCommand(name, true);
argc = ((U30)arg.Parameters[1]).Value;
if (null == userCommand)
{
throw new Exception(String.Format("Unknown command {0}.", name));
}
break;
}
args.Add(arg);
}
if (null == userCommand)
{
throw new Exception("Malformed inline block.");
}
instructions.Add(new Instruction(abc, userCommand, args));
break;
case (byte)Op.CallPropertyVoid:
name = NameUtil.ResolveMultiname(abc, (MultinameInfo)(abc.ConstantPool.MultinameTable[(int)((U30)inlineCommand.Parameters[0]).Value]));
if (inlineWrapper == name)
{
parse = false;
}
else
{
throw new Exception("Malformed inline block. Method calls are not accepted ...");
}
break;
}
}
#if DEBUG
Console.WriteLine("[+] Inline block parsed");
#endif
}
#endregion
#region INLINE Marker
else if (inlineMarker == name)
{
#if DEBUG
Console.WriteLine("[i] Body {0} has been marked as inline", body.Method.Value);
#endif
bool parse = true;
while (parse && i < n)
{
inlineCommand = Translator.ToCommand(il[i++]);
if (null == inlineCommand)
{
throw new Exception("Unknown opcode detected.");
}
i += inlineCommand.ReadParameters(il, i);
switch (inlineCommand.OpCode)
{
case (byte)Op.CallPropertyVoid:
name = NameUtil.ResolveMultiname(abc, (MultinameInfo)(abc.ConstantPool.MultinameTable[(int)((U30)inlineCommand.Parameters[0]).Value]));
if (inlineMarker == name)
{
parse = false;
}
else
{
throw new Exception("Malformed inline block. Method calls are not accepted ...");
}
break;
}
}
#if DEBUG
Console.WriteLine("[+] Inline marker parsed.");
#endif
patchBody = true;
}
#endregion
#region MAX_STACK Marker
else if (inlineMaxStack == name)
{
#if DEBUG
Console.WriteLine("[i] Body {0} has a manual maximum stack set.", body.Method.Value);
#endif
bool parse = true;
uint maxStackValue = 0;
bool hasMaxValue = false;
while (parse && i < n)
{
inlineCommand = Translator.ToCommand(il[i++]);
if (null == inlineCommand)
{
throw new Exception("Unknown opcode detected.");
}
i += inlineCommand.ReadParameters(il, i);
switch (inlineCommand.OpCode)
{
case (byte)Op.PushByte:
maxStackValue = (uint)((byte)inlineCommand.Parameters[0]);
hasMaxValue = true;
break;
case (byte)Op.PushShort:
maxStackValue = (uint)((U30)inlineCommand.Parameters[0]);
hasMaxValue = true;
break;
case (byte)Op.PushInt:
maxStackValue = (uint)((S32)abc.ConstantPool.IntTable[(int)((U30)inlineCommand.Parameters[0]).Value]).Value;
hasMaxValue = true;
break;
case (byte)Op.PushDouble:
throw new Exception("Max stack has to be an integer constant.");
case (byte)Op.CallPropertyVoid:
name = NameUtil.ResolveMultiname(abc, (MultinameInfo)(abc.ConstantPool.MultinameTable[(int)((U30)inlineCommand.Parameters[0]).Value]));
if (inlineMaxStack == name)
{
parse = false;
}
else
{
throw new Exception("Malformed inline block. Method calls are not accepted ...");
}
break;
}
}
#if DEBUG
Console.WriteLine("[+] MaxStack marker parsed.");
#endif
if (hasMaxValue)
{
hasManualMaxStack = true;
manualMaxStackValue = maxStackValue;
}
patchBody = true;
}
#endregion
else
{
instructions.Add(command);
}
break;
default:
instructions.Add(command);
break;
}
}
if (patchBody)
{
//
// We have to patch this function ...
// Note: We do not change the initScopeDepth
//
#if DEBUG
Console.WriteLine("[i] Patching body (id: {0})", bodyId);
#endif
CompilerAs3c compAs3c = new CompilerAs3c();
compAs3c.Compile(abc, instructions, labels, false);
// Now .. only patch if we find a correct stack!
U30 maxStack;
if (!hasManualMaxStack)
{
maxStack = ByteCodeAnalyzer.CalcMaxStack(compAs3c.Code);
}
else
{
maxStack = (U30)manualMaxStackValue;
}
if (hasManualMaxStack || 0 == (ByteCodeAnalyzer.Flags & ByteCodeAnalyzer.InvalidStack))
{
MethodInfo method = (MethodInfo)abc.Methods[(int)body.Method.Value];
body.MaxStack = maxStack;
body.MaxScopeDepth = body.InitScopeDepth + ByteCodeAnalyzer.CalcScopeDepth(compAs3c.Code);
U30 minLocalCount = method.ParameterCount;
U30 maxLocalCount = ByteCodeAnalyzer.CalcLocalCount(compAs3c.Code);
if (maxLocalCount.Value > minLocalCount.Value)
{
body.LocalCount = ByteCodeAnalyzer.CalcLocalCount(compAs3c.Code);
}
//else <- we would have unused parameters in a function...
body.Code = compAs3c.Code;
}
else
{
//
// What else? We will display warnings automatically but what about
// telling the guy in which function he has an invalid stack?
//
}
#if DEBUG
Console.WriteLine("[+] Body patched");
#endif
}
}
private void PatchBody(Abc46 abc, MethodBodyInfo body, int bodyId)
{
AVM2Command command;
AVM2Command inlineCommand;
Dictionary <string, Label> labels = new Dictionary <string, Label>();
ArrayList instructions = new ArrayList();
Label label;
string labelId;
byte[] il = body.Code;
uint i = 0;
uint n = (uint)il.Length;
uint addr;
string name;
bool patchBody = false;
bool ignoreBody = false;
_labelUtil.Clear();
while (i < n)
{
addr = i;
if (_labelUtil.IsMarked(addr))
{
labelId = String.Format(":{0}:", _labelUtil.GetLabelAt(addr).id);
label = new Label(labelId);
labels.Add(labelId, label);
instructions.Add(label);
}
command = Translator.ToCommand(il[i++]);
if (null == command)
{
throw new Exception("Unknown opcode detected.");
}
i += command.ReadParameters(il, i);
switch (command.OpCode)
{
case (byte)Op.Label:
labelId = String.Format(":{0}:", _labelUtil.GetLabelAt(addr).id);
label = new Label(labelId);
labels.Add(labelId, label);
instructions.Add(label);
break;
case (byte)Op.IfEqual:
case (byte)Op.IfFalse:
case (byte)Op.IfGreaterEqual:
case (byte)Op.IfGreaterThan:
case (byte)Op.IfLessEqual:
case (byte)Op.IfLowerThan:
case (byte)Op.IfNotEqual:
case (byte)Op.IfNotGreaterEqual:
case (byte)Op.IfNotGreaterThan:
case (byte)Op.IfNotLowerEqual:
case (byte)Op.IfNotLowerThan:
case (byte)Op.IfStrictEqual:
case (byte)Op.IfStrictNotEqual:
case (byte)Op.IfTrue:
case (byte)Op.Jump:
S24 offset = (S24)command.Parameters[0];
command.Parameters[0] = String.Format(":{0}:", _labelUtil.GetLabelAt((uint)(addr + 1 + offset.Length + offset.Value)).id);
instructions.Add(command);
break;
case (byte)Op.GetLex:
name = NameUtil.ResolveMultiname(abc, (MultinameInfo)(abc.ConstantPool.MultinameTable[(int)((U30)command.Parameters[0]).Value]));
if ("public::Math" == name || "Math" == name)
{
patchBody = true;
}
instructions.Add(command);
break;
case (byte)Op.LookupSwitch:
ignoreBody = true;
instructions.Add(command);
break;
default:
instructions.Add(command);
break;
}
}
if (ignoreBody)
{
#if DEBUG
Console.WriteLine("[-] Have to ignore body because of lookupswitch ...");
#endif
}
if (patchBody && !ignoreBody)
{
//
// We have to patch this function ...
// Note: We do not change the initScopeDepth
//
#if DEBUG
Console.WriteLine("[i] Patching body (id: {0})", bodyId);
#endif
CompilerAs3c compAs3c = new CompilerAs3c();
compAs3c.Compile(abc, instructions, labels, true);
// Now .. only patch if we find a correct stack!
U30 maxStack = maxStack = ByteCodeAnalyzer.CalcMaxStack(compAs3c.Code);
if (0 == (ByteCodeAnalyzer.Flags & ByteCodeAnalyzer.InvalidStack))
{
MethodInfo method = (MethodInfo)abc.Methods[(int)body.Method.Value];
body.MaxStack = maxStack;
body.MaxScopeDepth = body.InitScopeDepth + ByteCodeAnalyzer.CalcScopeDepth(compAs3c.Code);
U30 minLocalCount = method.ParameterCount;
U30 maxLocalCount = ByteCodeAnalyzer.CalcLocalCount(compAs3c.Code);
if (maxLocalCount.Value > minLocalCount.Value)
{
body.LocalCount = ByteCodeAnalyzer.CalcLocalCount(compAs3c.Code);
}
//else <- we would have unused parameters in a function...
body.Code = compAs3c.Code;
}
else
{
//
// What else? We will display warnings automatically but what about
// telling the guy in which function he has an invalid stack?
//
}
#if DEBUG
Console.WriteLine("[+] Body patched");
#endif
}
}
