def walk(self, node, parent=None): if isinstance(node, list): for idx, listitem in enumerate(node): self.walk(listitem, parent) if isinstance(listitem, ast2.Statement) and isinstance( parent, ast2.If): myif = parent call = listitem.expr if isinstance(call, ast2.Call): if isinstance(call.func, ast2.Name): if call.func.id == "_dispatch_once": decl = ast2.Declaration( typename="static dispatch_once_t", name="onceToken") args = [ ast2.AddressOf(variable=ast2.Name( id="onceToken")), call.args[1], ] call = ast2.Statement( expr=ast2.Call(func=ast2.Name( id="dispatch_once"), args=args)) node[:] = [decl, call] parent.test = ast2.Num(n=1) break elif isinstance(node, _ast.AST): for field in node.__class__._fields: subnode = getattr(node, field) self.walk(subnode, node)
def rewrite(self): self.process_block_to_be_embedded(self.ast.root) # Find captures cond = ast2.Assign(targets=[ ast2.FieldAccess(object=ast2.Name("block_literal"), field=Any()) ], value=Any(), decltype=None) result = AstMatcher().replace(self.ast.root, cond, self.callback_find_captures) # Replace block literal with ^{ ... } self.did_replace = False cond = ast2.AddressOf(variable=ast2.Name("block_literal")) result = AstMatcher().replace(self.ast.root, cond, self.callback) # bind captures if self.did_replace: cond = ast2.Assign(targets=[ ast2.FieldAccess(object=ast2.Name("block_literal"), field=Any()) ], value=Any(), decltype=None) result = AstMatcher().replace(self.ast.root, cond, self.callback2) # remove block_literal cond = ast2.Declaration(typename=Any(), name="block_literal") result = AstMatcher().replace(self.ast.root, cond, self.callback_remove_decl)
def get_variable(self, register): n = register.name if n in self.parameter_names: n = self.parameter_names[n] if n not in self.locals: self.locals[n] = ast2.Declaration(self.type_for_register(n), n) return ast2.Name(n)
def convert(self): cfg = self.func.ufunction.cfg assert(len(cfg.unassigned_bbs_with_cfg_roots) == 1) cfg_root = cfg.unassigned_bbs_with_cfg_roots[0] converter = UCodeConverter(self.func) # Add inputs as locals for (idx, p) in enumerate(self.func.ufunction.input_parameters): t = None if idx in self.func.parameters: t = self.func.parameters[idx].type converter.declare_argument(p.register, t) walker = CFGWalker(converter) ast_body = walker.visit(cfg_root) ast_body = [l for l in list(converter.locals.values()) if l is not None] + ast_body #f = FunctionDef('a', None, ast_body, []) #print ast.dump(f) from analysis.binary import ObjCMethod returntype = self.func.returns.type if self.func.method is not None: args = [ast2.Declaration(typename=self.func.parameters[idx + 2].type.name, name=p.name) for (idx, p) in enumerate(self.func.ufunction.input_parameters[2:])] classname = self.func.method.cls.name selector = self.func.method.name static = self.func.method.method_type == ObjCMethod.METHOD_TYPE_CLASS f = ast2.ObjCFunctionDef(classname=classname, selector=selector, args=args, body=ast_body, static=static, returntype=returntype) else: args = [ast2.Declaration(typename="long", name=p.name) for (idx, p) in enumerate(self.func.ufunction.input_parameters[0:])] f = ast2.CFunctionDef(name=self.func.name, args=args, body=ast_body, returntype=returntype) return f, converter.globals
def convert1(self, o): c = self.convert1 if isinstance(o, UCodeAdd): return ast2.Assign(targets=[c(o.destination())], value=ast2.BinOp(c(o.source1()), ast2.Add(), c(o.source2())), decltype=None) elif isinstance(o, UCodeRet): if len(o.operands) == 0: return ast2.Return(None) else: assert(len(o.operands) == 1) return ast2.Return(c(o.operands[0])) elif isinstance(o, UCodeCall): call = ast2.Call(c(o.callee()), [c(p) for p in o.params()]) if o.has_destination: return ast2.Assign(targets=[c(o.destination())], value=call, decltype=None) else: return ast2.Statement(expr=call) elif isinstance(o, UCodeMov): return ast2.Assign(targets=[c(o.destination())], value=c(o.source()), decltype=None) elif isinstance(o, UCodeRegister): return self.get_variable(o) elif isinstance(o, UCodeStore): deref = ast2.Dereference(c(o.pointer())) return ast2.Assign(targets=[deref], value=c(o.source()), decltype=None) elif isinstance(o, UCodeLoad): deref = ast2.Dereference(c(o.pointer())) return ast2.Assign(targets=[c(o.destination())], value=deref, decltype=None) elif isinstance(o, UCodeAddressOfLocal): return ast2.Assign(targets=[c(o.destination())], value=ast2.AddressOf(variable=c(o.source())), decltype=None) elif isinstance(o, UCodeSetMember): field = "off_%x" % o.offset() target = ast2.FieldAccess(object=c(o.destination()), field=field) return ast2.Assign(targets=[target], value=c(o.value()), decltype=None) elif isinstance(o, UCodeGetMember): field = "off_%x" % o.offset() value = ast2.FieldAccess(object=c(o.value()), field=field) return ast2.Assign(targets=[c(o.destination())], value=value, decltype=None) elif isinstance(o, UCodeBranch): return ast2.Statement(c(o.condition())) elif isinstance(o, UCodeSetFlag): if o.type == UCodeSetFlag.TYPE_ZERO and o.operation == UCodeSetFlag.OPERATION_SUB: comparison = ast2.Equals(left=c(o.source1()), right=c(o.source2())) elif o.type == UCodeSetFlag.TYPE_ZERO and o.operation == UCodeSetFlag.OPERATION_AND: comparison = ast2.BinOp(left=c(o.source1()), op=ast2.And(), right=c(o.source2())) elif o.type == UCodeSetFlag.TYPE_CARRY and o.operation == UCodeSetFlag.OPERATION_SUB: comparison = ast2.BinOp(left=c(o.source1()), op=ast2.Gt(), right=c(o.source2())) else: comparison = ast2.Todo(str(o)) target = c(o.destination()) return ast2.Assign(targets=[target], value=comparison, decltype=None) elif isinstance(o, UCodeNeg): target = c(o.destination()) value = ast2.Negation(value=c(o.source1())) return ast2.Assign(targets=[target], value=value, decltype=None) elif isinstance(o, UCodeTruncate) or isinstance(o, UCodeExtend): target = c(o.destination()) value = c(o.source()) return ast2.Assign(targets=[target], value=value, decltype=None) elif isinstance(o, UCodeArithmeticOperation): target = c(o.destination()) mnem_to_op = {"uADD": ast2.Add, "uSUB": ast2.Sub, "uMUL": ast2.Mult, "uDIV": ast2.Div, "uMOD": ast2.Mod, "uAND": ast2.And, "uOR": ast2.Or, "uXOR": ast2.Xor, "uSHL": ast2.Shl, "uSHR": ast2.Shr} op = mnem_to_op[o.mnem()]() value = ast2.BinOp(left=c(o.source1()), op=op, right=c(o.source2())) return ast2.Assign(targets=[target], value=value, decltype=None) elif isinstance(o, UCodeInstruction): return ast2.Statement(ast2.Todo(str(o))) # TODO elif isinstance(o, UCodeConstant): if not o.name: return ast2.Num(n=o.value) if o.name.startswith("_OBJC_CFSTRING_$_"): if o.value in self.func.binary.cfstrings: return ast2.ObjCString(value=self.func.binary.cfstrings[o.value].string) if o.name.startswith("_OBJC_SELECTOR_$_"): return ast2.ObjCSelector(value=o.name.replace("_OBJC_SELECTOR_$_", "")) if o.name not in self.globals: self.globals[o.name] = ast2.Declaration("long", o.name) return ast2.Name(o.name) else: return ast2.Todo(str(o)) # TODO
def rewrite(self): self.walk(self.ast.root.body) cond = ast2.Declaration(name=Any(), typename=Any()) AstMatcher().replace(self.ast.root, cond, self.callback)