本文通过clang的LibTooling来实现Objective-C源码中方法名的混淆。
1.准备环境
需要下载Clang和LLVM。简单说一下，Clang是编译器的前端，能够解析C/C++/OC代码，Clang生成Intermediate Representation代码(简称IR)；LLVM是编译器的后端，使用Clang生成的IR来生成不同平台的目标代码。
本人使用的是Xcode 9.4，下载的Clang和LLVM都是release_39这个分支的代码，亲测可用。
$ git clone -b release_39 http://llvm.org/git/llvm llvm
$ cd llvm/tools
$ git clone -b release_39 http://llvm.org/git/clang clang
下载后，进入llvm目录，创建llvm_build目录，然后进入：
$ cd llvm && mkdir llvm_build && cd llvm_build
使用Xcode完成cmake：
$ cmake -G "Xcode" ..
等待完成。
2.创建工程
Clang的源码在llvm/tools/clang/下主要是include和lib文件夹，tools文件夹下是使用Clang的库实现的一些工具。我们的混淆工具也是基于Clang库，所以项目也创建在tools下边，与其他工具在同一层级下，创建我们的工程目录clang-autostats：
$ cd llvm/tools/clang/tools && mkdir clang-autostats
$ cd clang-autostats
然后创建源文件ClangAutoStats.cpp。在相同目录下添加CMakeLists.txt文件，内容如下：
set(LLVM_LINK_COMPONENTS
Support
)
add_clang_executable(ClangAutoStats
ClangAutoStats.cpp
)
target_link_libraries(ClangAutoStats
clangAST
clangBasic
clangDriver
clangFormat
clangLex
clangParse
clangSema
clangFrontend
clangTooling
clangToolingCore
clangRewrite
clangRewriteFrontend
)
if(UNIX)
set(CLANGXX_LINK_OR_COPY create_symlink)
else()
set(CLANGXX_LINK_OR_COPY copy)
endif()
接下来将ClangAutoStats工程添加到LLVM中，进入llvm/tools/clang/tools目录，在CMakeList.txt最后一行加入文字：
echo 'add_subdirectory(clang-autostats)' >> ./CMakeLists.txt
回到llvm_build，再次执行“cmake -G “Xcode” ..”。打开llvm_build/LLVM.xcodeproj，在Clang executables文件夹下会出现我们的工程目录。
使用Xcode打开LLVM.xcodeproj时，创建新的scheme，选择ClangAutoStats，如下图所示。
创建新的scheme
3.替换方法名
语法树AST
示例代码：
Hello1.h
#import <UIKit/UIKit.h>
#import <Foundation/Foundation.h>
@protocol TTProtocol <NSObject>
- (void)protocolMethod;
@end
@interface HelloViewController : UIViewController
- (void)hahaha;
- (instancetype)sayHello;
- (void)sayOK:(NSString *)content toSomeOne:(NSString *)name;
+ (void)clmethod;
@end
Hello1.m
#import <UIKit/UIKit.h>
#import <Foundation/Foundation.h>
#import "Hello1.h"
@interface HelloViewController () <TTProtocol>
@property (nonatomic, assign) NSInteger index;
@end
@interface HelloViewController (hehehe)
@end
@implementation HelloViewController
- (NSInteger)hahaha {
NSInteger a = 100;
a += 1;
return a;
}
- (instancetype)sayHello {
NSLog(@"Hi");
return self;
}
- (void)sayOK:(NSString *)content toSomeOne:(NSString *)name {
NSLog(@"123123");
}
- (void)protocolMethod {
NSLog(@"3333");
}
+ (void)clmethod {
NSLog(@"32233");
}
@end
输入如下命令，将示例代码解析为语法树：
clang -Xclang -ast-dump -fsyntax-only Hello1.m
解析结果如下：
|-ObjCProtocolDecl 0x7fc9de353d00 <./Hello1.h:4:1, line:8:2> line:4:11 TTProtocol
| |-ObjCProtocol 0x7fc9dc96c170 'NSObject'
| `-ObjCMethodDecl 0x7fc9de353db0 <line:6:1, col:23> col:1 - protocolMethod 'void'
|-ObjCInterfaceDecl 0x7fc9de353e38 <line:10:1, line:15:2> line:10:12 HelloViewController
| |-ObjCImplementation 0x7fc9de3545f8 'HelloViewController'
| |-ObjCMethodDecl 0x7fc9de353f50 <line:11:1, col:15> col:1 - hahaha 'void'
| |-ObjCMethodDecl 0x7fc9de353ff8 <line:12:1, col:25> col:1 - sayHello 'instancetype':'id'
| |-ObjCMethodDecl 0x7fc9de3540c0 <line:13:1, col:61> col:1 - sayOK:toSomeOne: 'void'
| | |-ParmVarDecl 0x7fc9de354148 <col:16, col:27> col:27 content 'NSString *'
| | `-ParmVarDecl 0x7fc9de3541a8 <col:46, col:57> col:57 name 'NSString *'
| `-ObjCMethodDecl 0x7fc9de354228 <line:14:1, col:17> col:1 + clmethod 'void'
|-ObjCCategoryDecl 0x7fc9de3542b0 <Hello1.m:5:1, line:9:2> line:5:12
| |-ObjCInterface 0x7fc9de353e38 'HelloViewController'
| |-ObjCProtocol 0x7fc9de353d00 'TTProtocol'
| |-ObjCPropertyDecl 0x7fc9de354370 <line:7:1, col:41> col:41 index 'NSInteger':'long' assign readwrite nonatomic unsafe_unretained
| |-ObjCMethodDecl 0x7fc9de3543e8 <col:41> col:41 implicit - index 'NSInteger':'long'
| `-ObjCMethodDecl 0x7fc9de354470 <col:41> col:41 implicit - setIndex: 'void'
| `-ParmVarDecl 0x7fc9de3544f8 <col:41> col:41 index 'NSInteger':'long'
|-ObjCCategoryDecl 0x7fc9de354560 <line:11:1, line:13:2> line:11:12 hehehe
| `-ObjCInterface 0x7fc9de353e38 'HelloViewController'
`-ObjCImplementationDecl 0x7fc9de3545f8 <line:15:1, line:38:1> line:15:17 HelloViewController
|-ObjCInterface 0x7fc9de353e38 'HelloViewController'
|-ObjCMethodDecl 0x7fc9de354690 <line:16:1, line:20:1> line:16:1 - hahaha 'NSInteger':'long'
| |-ImplicitParamDecl 0x7fc9de354cf8 <<invalid sloc>> <invalid sloc> implicit self 'HelloViewController *'
| |-ImplicitParamDecl 0x7fc9de354d58 <<invalid sloc>> <invalid sloc> implicit _cmd 'SEL':'SEL *'
| |-VarDecl 0x7fc9de354dc8 <line:17:5, col:19> col:15 used a 'NSInteger':'long' cinit
| | `-ImplicitCastExpr 0x7fc9de354e48 <col:19> 'NSInteger':'long' <IntegralCast>
| | `-IntegerLiteral 0x7fc9de354e28 <col:19> 'int' 100
| `-CompoundStmt 0x7fc9de354f68 <line:16:21, line:20:1>
| |-DeclStmt 0x7fc9de354e60 <line:17:5, col:22>
| | `-VarDecl 0x7fc9de354dc8 <col:5, col:19> col:15 used a 'NSInteger':'long' cinit
| | `-ImplicitCastExpr 0x7fc9de354e48 <col:19> 'NSInteger':'long' <IntegralCast>
| | `-IntegerLiteral 0x7fc9de354e28 <col:19> 'int' 100
| |-CompoundAssignOperator 0x7fc9de354ed8 <line:18:5, col:10> 'NSInteger':'long' '+=' ComputeLHSTy='long' ComputeResultTy='long'
| | |-DeclRefExpr 0x7fc9de354e78 <col:5> 'NSInteger':'long' lvalue Var 0x7fc9de354dc8 'a' 'NSInteger':'long'
| | `-ImplicitCastExpr 0x7fc9de354ec0 <col:10> 'long' <IntegralCast>
| | `-IntegerLiteral 0x7fc9de354ea0 <col:10> 'int' 1
| `-ReturnStmt 0x7fc9de354f50 <line:19:5, col:12>
| `-ImplicitCastExpr 0x7fc9de354f38 <col:12> 'NSInteger':'long' <LValueToRValue>
| `-DeclRefExpr 0x7fc9de354f10 <col:12> 'NSInteger':'long' lvalue Var 0x7fc9de354dc8 'a' 'NSInteger':'long'
|-ObjCMethodDecl 0x7fc9de354740 <line:21:1, line:24:1> line:21:1 - sayHello 'instancetype':'id'
| |-ImplicitParamDecl 0x7fc9de354f90 <<invalid sloc>> <invalid sloc> implicit used self 'HelloViewController *'
| |-ImplicitParamDecl 0x7fc9de354ff0 <<invalid sloc>> <invalid sloc> implicit _cmd 'SEL':'SEL *'
| `-CompoundStmt 0x7fc9de3551f8 <col:26, line:24:1>
| |-CallExpr 0x7fc9de355140 <line:22:5, col:16> 'void'
| | |-ImplicitCastExpr 0x7fc9de355128 <col:5> 'void (*)(id, ...)' <FunctionToPointerDecay>
| | | `-DeclRefExpr 0x7fc9de355050 <col:5> 'void (id, ...)' Function 0x7fc9dd2bbc08 'NSLog' 'void (id, ...)'
| | `-ImplicitCastExpr 0x7fc9de355170 <col:11, col:12> 'id':'id' <BitCast>
| | `-ObjCStringLiteral 0x7fc9de3550a8 <col:11, col:12> 'NSString *'
| | `-StringLiteral 0x7fc9de355078 <col:12> 'char [3]' lvalue "Hi"
| `-ReturnStmt 0x7fc9de3551e0 <line:23:5, col:12>
| `-ImplicitCastExpr 0x7fc9de3551c8 <col:12> 'instancetype':'id' <BitCast>
| `-ImplicitCastExpr 0x7fc9de3551b0 <col:12> 'HelloViewController *' <LValueToRValue>
| `-DeclRefExpr 0x7fc9de355188 <col:12> 'HelloViewController *' lvalue ImplicitParam 0x7fc9de354f90 'self' 'HelloViewController *'
|-ObjCMethodDecl 0x7fc9de354810 <line:26:1, line:28:1> line:26:1 - sayOK:toSomeOne: 'void'
| |-ImplicitParamDecl 0x7fc9de355218 <<invalid sloc>> <invalid sloc> implicit self 'HelloViewController *'
| |-ImplicitParamDecl 0x7fc9de355278 <<invalid sloc>> <invalid sloc> implicit _cmd 'SEL':'SEL *'
| |-ParmVarDecl 0x7fc9de354898 <col:16, col:27> col:27 content 'NSString *'
| |-ParmVarDecl 0x7fc9de3548f8 <col:46, col:57> col:57 name 'NSString *'
| `-CompoundStmt 0x7fc9de3553b0 <col:62, line:28:1>
| `-CallExpr 0x7fc9de355368 <line:27:5, col:20> 'void'
| |-ImplicitCastExpr 0x7fc9de355350 <col:5> 'void (*)(id, ...)' <FunctionToPointerDecay>
| | `-DeclRefExpr 0x7fc9de3552d8 <col:5> 'void (id, ...)' Function 0x7fc9dd2bbc08 'NSLog' 'void (id, ...)'
| `-ImplicitCastExpr 0x7fc9de355398 <col:11, col:12> 'id':'id' <BitCast>
| `-ObjCStringLiteral 0x7fc9de355330 <col:11, col:12> 'NSString *'
| `-StringLiteral 0x7fc9de355300 <col:12> 'char [7]' lvalue "123123"
|-ObjCMethodDecl 0x7fc9de354978 <line:30:1, line:32:1> line:30:1 - protocolMethod 'void'
| |-ImplicitParamDecl 0x7fc9de3553c8 <<invalid sloc>> <invalid sloc> implicit self 'HelloViewController *'
| |-ImplicitParamDecl 0x7fc9de355428 <<invalid sloc>> <invalid sloc> implicit _cmd 'SEL':'SEL *'
| `-CompoundStmt 0x7fc9de355560 <col:24, line:32:1>
| `-CallExpr 0x7fc9de355518 <line:31:5, col:18> 'void'
| |-ImplicitCastExpr 0x7fc9de355500 <col:5> 'void (*)(id, ...)' <FunctionToPointerDecay>
| | `-DeclRefExpr 0x7fc9de355488 <col:5> 'void (id, ...)' Function 0x7fc9dd2bbc08 'NSLog' 'void (id, ...)'
| `-ImplicitCastExpr 0x7fc9de355548 <col:11, col:12> 'id':'id' <BitCast>
| `-ObjCStringLiteral 0x7fc9de3554e0 <col:11, col:12> 'NSString *'
| `-StringLiteral 0x7fc9de3554b0 <col:12> 'char [5]' lvalue "3333"
|-ObjCMethodDecl 0x7fc9de354a18 <line:34:1, line:36:1> line:34:1 + clmethod 'void'
| |-ImplicitParamDecl 0x7fc9de355578 <<invalid sloc>> <invalid sloc> implicit self 'Class':'Class'
| |-ImplicitParamDecl 0x7fc9de3555d8 <<invalid sloc>> <invalid sloc> implicit _cmd 'SEL':'SEL *'
| `-CompoundStmt 0x7fc9de355710 <col:18, line:36:1>
| `-CallExpr 0x7fc9de3556c8 <line:35:5, col:19> 'void'
| |-ImplicitCastExpr 0x7fc9de3556b0 <col:5> 'void (*)(id, ...)' <FunctionToPointerDecay>
| | `-DeclRefExpr 0x7fc9de355638 <col:5> 'void (id, ...)' Function 0x7fc9dd2bbc08 'NSLog' 'void (id, ...)'
| `-ImplicitCastExpr 0x7fc9de3556f8 <col:11, col:12> 'id':'id' <BitCast>
| `-ObjCStringLiteral 0x7fc9de355690 <col:11, col:12> 'NSString *'
| `-StringLiteral 0x7fc9de355660 <col:12> 'char [6]' lvalue "32233"
|-ObjCIvarDecl 0x7fc9de354aa8 <line:7:41> col:41 implicit _index 'NSInteger':'long' synthesize private
`-ObjCPropertyImplDecl 0x7fc9de354b00 <<invalid sloc>, col:41> <invalid sloc> index synthesize
|-ObjCProperty 0x7fc9de354370 'index'
`-ObjCIvar 0x7fc9de354aa8 '_index' 'NSInteger':'long'
从上述语法树解析结果来看，”- (void)hahaha”函数在头文件中的定义:
ObjCMethodDecl 0x7fc9de353f50 <line:11:1, col:15> col:1 - hahaha 'void'
和源文件中的实现：
ObjCMethodDecl 0x7fc9de354690 <line:16:1, line:20:1> line:16:1 - hahaha 'NSInteger':'long'
都可以从语法树中获取到，所以使用语法树完全可以定位具体函数位置，并对函数名字进行替换。
main函数
int main(int argc, const char **argv) {
CommonOptionsParser op(argc, argv, OptsCategory);
vector<string> commands;
ClangTool Tool(op.getCompilations(), commands);
// 1> 添加要遍历的文件
commands.push_back("/Users/tom555cat/develop/RewriteDir/Hello1.m");
// 搜集selector阶段
selectorPass = true;
int result = Tool.run(newFrontendActionFactory<ExampleFrontendAction>().get());
// 替换函数名阶段
selectorPass = false;
result = Tool.run(newFrontendActionFactory<ExampleFrontendAction>().get());
return result;
}
这里要关注的有两点：
1>提供需要遍历语法树的Objective-C源文件，即.m文件；当然.h文件也可以，但是有个坑，后面会说明。
2> 创建了一个新的FrontedAction，接下来关注创建的ExampleFrontedAction类。
ExampleFrontedAction
class ExampleFrontendAction : public ASTFrontendAction {
private:
Rewriter rewriter;
public:
virtual unique_ptr<ASTConsumer> CreateASTConsumer(CompilerInstance &CI, StringRef file) {
rewriter.setSourceMgr(CI.getSourceManager(), CI.getLangOpts());
CI.getPreprocessor();
// 1> 需要为每一个translation unit提供一个ASTConsumer
return make_unique<ExampleASTConsumer>(rewriter);
}
// 2> 解析完成后，将内容回写到对应文件中
void EndSourceFileAction() override {
SourceManager &SM = rewriter.getSourceMgr();
llvm::errs() << "** EndSourceFileAction for: "
<< SM.getFileEntryForID(SM.getMainFileID())->getName() << "\n";
string Filename = SM.getFileEntryForID(SM.getMainFileID())->getName();
std::error_code error_code;
llvm::raw_fd_ostream outFile(Filename, error_code, llvm::sys::fs::F_None);
// 将Rewriter结果输出到文件中
rewriter.getEditBuffer(SM.getMainFileID()).write(outFile);
// 将Rewriter结果输出在控制台上
// rewriter.getEditBuffer(SM.getMainFileID()).write(llvm::outs());
}
};
ExampleFrontedAction->ASTFrontedAction->FrontedAction，这是这三个类的继承关系。
FrontendAction是一个在编译过程中允许执行用户特殊操作的接口。为了获取语法树AST，clang提供了ASTFrontendAction，而对语法树进行操作则需要用户为每一个translation unit提供一个ASTConsumer，对应标注1>。
FrontendAction：Abstract base class for actions which can be performed by the frontend. FrontendAction有三个public interface。
BeginSourceFile():该函数运行在options和FrontendAction初始化完成之后，每个文件Parse之前。如果该函数返回false，则后面的步骤不会执行。
Excute()：Set the source manager’s main input file, and run the action.
EndSourceFile()：每个文件在parse完之后，做一些清理和内存释放工作。(Perform any per-file post processing, deallocate per-file objects, and run statistics and output file cleanup code)。
我们通过遍历AST过程中，对方法名进行了修改，需要处理完一个文件后就将内容回写到对应的文件中，因此我们重载了EndSourceFileAction()方法。对应标注2>。
ASTConsumer和RecursiveASTVisitor
ASTConsumer提供了对AST进行操作的接口，具体对语法树每一个节点的操作定义在了RecursiveASTVisitor中。
RecursiveASTVisitor提供了对大多数AST node节点访问的hook方法。我们要对方法名进行混淆，也就是重写，需要能够访问到Interface/Category中方法名的定义；Interface/Category中Implementation中方法的实现；发送消息处的方法名。
我们定义了两个ASTConsumer：
- SelectorASTConsumer
主要作用是抽取源码中@selector中的函数名并保存，因为从@selector中的函数反推到函数所在的类实现比较复杂，所以暂时不对@selector出现的函数进行重命名。 - ExampleASTConsumer
主要作用就是对函数定义和消息发送中的函数名字进行重命名。
SelectorASTConsumer & SelectorVisitor
class SelectorVisitor : public RecursiveASTVisitor<SelectorVisitor> {
private:
//ASTContext *astContext; // used for getting additional AST info
//typedef clang::RecursiveASTVisitor<RewritingVisitor> Base;
Rewriter &rewriter;
public:
explicit SelectorVisitor(Rewriter &R)
: rewriter{R} // initialize private members
{}
bool VisitObjCSelectorExpr(ObjCSelectorExpr *selectorExpr) {
Selector sel = selectorExpr->getSelector();
errs() << "the selector name is:" << sel.getAsString() << "\n";
selectorMap.insert({sel.getAsString(), sel});
return true;
}
};
class SelectorASTConsumer: public ASTConsumer {
private:
SelectorVisitor visitor;
public:
explicit SelectorASTConsumer(Rewriter &R) : visitor(R) {}
virtual void HandleTranslationUnit(ASTContext &Context) {
visitor.TraverseDecl(Context.getTranslationUnitDecl());
}
};
ExampleASTConsumer & ExampleVisitor
class ExampleASTConsumer : public ASTConsumer {
private:
ExampleVisitor visitor;
public:
// override the constructor in order to pass CI
explicit ExampleASTConsumer(Rewriter &R)
: visitor(R) // initialize the visitor
{ }
// override this to call our ExampleVisitor on the entire source file
virtual void HandleTranslationUnit(ASTContext &Context) {
/* we can use ASTContext to get the TranslationUnitDecl, which is
a single Decl that collectively represents the entire source file */
visitor.TraverseDecl(Context.getTranslationUnitDecl());
}
};
class ExampleVisitor : public RecursiveASTVisitor<ExampleVisitor> {
private:
//ASTContext *astContext; // used for getting additional AST info
//typedef clang::RecursiveASTVisitor<RewritingVisitor> Base;
Rewriter &rewriter;
public:
explicit ExampleVisitor(Rewriter &R)
: rewriter{R} // initialize private members
{}
// 判断函数是否能够混淆
bool canObfuscate(ObjCMethodDecl *MD) {
// 如果该方法是协议方法，不进行混淆
ObjCInterfaceDecl *ID = MD->getClassInterface();
if (!ID) {
return false;
}
for (ObjCProtocolDecl *protocol : ID->all_referenced_protocols()) {
if (protocol->lookupMethod(MD->getSelector(), MD->isInstanceMethod())) {
return false;
}
}
// 不混淆读写方法/系统方法/init前缀方法/set前缀方法/zdd_前缀方法
string methodName = MD->getNameAsString();
if (MD->isPropertyAccessor() || isInSystem(MD) || methodName.find("set") == 0 || methodName.find("init") == 0 || methodName.find("zdd_") == 0) {
return false;
}
return true;
}
// 1> 混淆方法声明/定义处的名字
bool VisitObjCMethodDecl(ObjCMethodDecl *D) {
this->renameFunctionName(D);
return true;
}
// 2> 混淆发送消息处的方法名字
bool VisitObjCMessageExpr(ObjCMessageExpr *messageExpr) {
// 跳过系统类
ObjCMethodDecl *MD = messageExpr->getMethodDecl();
if (MD) {
if(canObfuscate(MD) == false) {
return true;
}
Selector selector = messageExpr->getSelector();
// 方法是通过.调用还是通过发消息调用
string funcNameWithPrefix = "zdd_" + selector.getNameForSlot(0).str();
errs() << "first selector slot size:" << selector.getNameForSlot(0).size() << "\n";
rewriter.ReplaceText(messageExpr->getSelectorStartLoc(),
selector.getNameForSlot(0).size(),
funcNameWithPrefix);
}
return true;
}
// 修改函数声明处的函数名字
void renameFunctionName(ObjCMethodDecl *MD) {
// 判断是否应该混淆方法名
if (canObfuscate(MD) == false) {
return;
}
string funcName = MD->getNameAsString();
Selector selector = MD->getSelector();
string funcNameWithPrefix = "zdd_" + selector.getNameForSlot(0).str();
rewriter.ReplaceText(MD->getSelectorStartLoc(), selector.getNameForSlot(0).size(), funcNameWithPrefix);
}
bool isInSystem(Decl *decl) {
SourceManager &SM = rewriter.getSourceMgr();
if (SM.isInSystemHeader(decl->getLocation()) ||
SM.isInExternCSystemHeader(decl->getLocation())) {
return true;
}
return false;
}
};
修改方法声明/定义处的方法名字
VisitObjCMethodDecl()回调能够获取到AST中方法的声明/定义节点，唯一的区别是：在方法声明处，D->hasBody()为false，而在方法定义处，D->hasBody()为true，但是这并不影响我们修改方法名字。
但是有些方法名字不能混淆，比如ViewController中实现协议UITableViewDelegate的方法的名字，在函数canObfuscate()中，通过查找该方法是否是类实现的协议方法来过滤掉。
目前没有做属性读写方法的混淆，直接过滤掉了，通过ObjCMethodDecl的** isPropertyAccessor()方法可以判断是否是属性读写方法。有时候在category中定义关联属性，并自定义读写方法，这时通过isPropertyAccessor()是无法判断方法是否是属性读写方法的，我们在canObfuscate()中判断前缀是否是“set”**来判断。
修改发送消息处的方法名
VisitObjCMessageExpr回调能够获取AST中发送消息的节点，通过canObfuscate判断是否能够混淆，然后进行混淆。
代码中的混淆方法
代码中的混淆方法仅仅是在方法selector第一个slot前加上了zdd_前缀，可以替换为自己的混淆方法。
4.运行代码
通过Xcode调试代码
项目源码地址：https://github.com/tom555cat/obfuscator-clang.git
将源代码粘贴进ClangAutoStats.cpp之后，还需要设置Xcode中Scheme的参数：
/Users/tongleiming/Documents/test/RewriteDir
--
-mios-simulator-version-min=9.0
-isysroot
/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator.sdk
-isystem
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/clang/9.1.0/include
-I/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/include/c++/v1
-I/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator.sdk/usr/include
-F/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator.sdk/System/Library/Frameworks
-ferror-limit=9999999
-ObjC
第一行参数为要修改代码的目录。
最后一行参数”-ObjC”主要是针对修改头文件中方法名添加的。
编译成可执行文件
编译完成的可执行文件ClangAutoStats在github上的路径为：https://github.com/tom555cat/obfuscator-clang/ClangAutoStats。
下载后通过下面方式执行：
./ClangAutoStats SourceFilesDirectory -- -ferror-limit=9999999 -ObjC
