AFLplusplus/instrumentation/afl-llvm-lto-instrumentlist.so.cc
2020-11-30 21:54:18 +01:00

147 lines
3.4 KiB
C++

/*
american fuzzy lop++ - LLVM-mode instrumentation pass
---------------------------------------------------
Written by Laszlo Szekeres <lszekeres@google.com> and
Michal Zalewski
LLVM integration design comes from Laszlo Szekeres. C bits copied-and-pasted
from afl-as.c are Michal's fault.
Copyright 2015, 2016 Google Inc. All rights reserved.
Copyright 2019-2020 AFLplusplus Project. All rights reserved.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at:
http://www.apache.org/licenses/LICENSE-2.0
This library is plugged into LLVM when invoking clang through afl-clang-fast.
It tells the compiler to add code roughly equivalent to the bits discussed
in ../afl-as.h.
*/
#define AFL_LLVM_PASS
#include "config.h"
#include "debug.h"
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <list>
#include <string>
#include <fstream>
#include <sys/time.h>
#include <fnmatch.h>
#include "llvm/IR/DebugInfo.h"
#include "llvm/IR/BasicBlock.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/LegacyPassManager.h"
#include "llvm/IR/Module.h"
#include "llvm/Support/Debug.h"
#include "llvm/Transforms/IPO/PassManagerBuilder.h"
#include "llvm/IR/CFG.h"
#include "afl-llvm-common.h"
using namespace llvm;
namespace {
class AFLcheckIfInstrument : public ModulePass {
public:
static char ID;
AFLcheckIfInstrument() : ModulePass(ID) {
if (getenv("AFL_DEBUG")) debug = 1;
initInstrumentList();
}
bool runOnModule(Module &M) override;
// StringRef getPassName() const override {
// return "American Fuzzy Lop Instrumentation";
// }
protected:
std::list<std::string> myInstrumentList;
};
} // namespace
char AFLcheckIfInstrument::ID = 0;
bool AFLcheckIfInstrument::runOnModule(Module &M) {
/* Show a banner */
setvbuf(stdout, NULL, _IONBF, 0);
if ((isatty(2) && !getenv("AFL_QUIET")) || getenv("AFL_DEBUG") != NULL) {
SAYF(cCYA "afl-llvm-lto-instrumentlist" VERSION cRST
" by Marc \"vanHauser\" Heuse <mh@mh-sec.de>\n");
} else if (getenv("AFL_QUIET"))
be_quiet = 1;
for (auto &F : M) {
if (F.size() < 1) continue;
// fprintf(stderr, "F:%s\n", F.getName().str().c_str());
if (isInInstrumentList(&F)) {
if (debug)
DEBUGF("function %s is in the instrument file list\n",
F.getName().str().c_str());
} else {
if (debug)
DEBUGF("function %s is NOT in the instrument file list\n",
F.getName().str().c_str());
auto & Ctx = F.getContext();
AttributeList Attrs = F.getAttributes();
AttrBuilder NewAttrs;
NewAttrs.addAttribute("skipinstrument");
F.setAttributes(
Attrs.addAttributes(Ctx, AttributeList::FunctionIndex, NewAttrs));
}
}
return true;
}
static void registerAFLcheckIfInstrumentpass(const PassManagerBuilder &,
legacy::PassManagerBase &PM) {
PM.add(new AFLcheckIfInstrument());
}
static RegisterStandardPasses RegisterAFLcheckIfInstrumentpass(
PassManagerBuilder::EP_ModuleOptimizerEarly,
registerAFLcheckIfInstrumentpass);
static RegisterStandardPasses RegisterAFLcheckIfInstrumentpass0(
PassManagerBuilder::EP_EnabledOnOptLevel0,
registerAFLcheckIfInstrumentpass);