lib/dfsan/dfsan.h

//===-- dfsan.h -------------------------------------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file is a part of DataFlowSanitizer.
//
// Private DFSan header.
//===----------------------------------------------------------------------===//

#ifndef DFSAN_H
#define DFSAN_H

#include "sanitizer_common/sanitizer_internal_defs.h"

#include "dfsan_flags.h"
#include "dfsan_platform.h"

using __sanitizer::u16;
using __sanitizer::u32;
using __sanitizer::uptr;

// Copy declarations from public sanitizer/dfsan_interface.h header here.
typedef u16 dfsan_label;
typedef u32 dfsan_origin;

struct dfsan_label_info {
  dfsan_label l1;
  dfsan_label l2;
  const char *desc;
  void *userdata;
};

extern "C" {
void dfsan_add_label(dfsan_label label, void *addr, uptr size);
void dfsan_set_label(dfsan_label label, void *addr, uptr size);
dfsan_label dfsan_read_label(const void *addr, uptr size);
dfsan_label dfsan_union(dfsan_label l1, dfsan_label l2);
// Zero out [offset, offset+size) from __dfsan_arg_tls.
void dfsan_clear_arg_tls(uptr offset, uptr size);
// Zero out the TLS storage.
void dfsan_clear_thread_local_state();

// Return the origin associated with the first taint byte in the size bytes
// from the address addr.
dfsan_origin dfsan_read_origin_of_first_taint(const void *addr, uptr size);

// Copy or move the origins of the len bytes from src to dst.
void dfsan_mem_origin_transfer(const void *dst, const void *src, uptr len);
}  // extern "C"

template <typename T>
void dfsan_set_label(dfsan_label label, T &data) {  // NOLINT
  dfsan_set_label(label, (void *)&data, sizeof(T));
}

namespace __dfsan {

void InitializeInterceptors();

inline dfsan_label *shadow_for(void *ptr) {
  return (dfsan_label *) ((((uptr) ptr) & ShadowMask()) << 1);
}

inline const dfsan_label *shadow_for(const void *ptr) {
  return shadow_for(const_cast<void *>(ptr));
}

inline uptr unaligned_origin_for(uptr ptr) {
  return OriginAddr() + (ptr & ShadowMask());
}

inline dfsan_origin *origin_for(void *ptr) {
  auto aligned_addr = unaligned_origin_for(reinterpret_cast<uptr>(ptr)) &
                      ~(sizeof(dfsan_origin) - 1);
  return reinterpret_cast<dfsan_origin *>(aligned_addr);
}

inline const dfsan_origin *origin_for(const void *ptr) {
  return origin_for(const_cast<void *>(ptr));
}

inline bool is_shadow_addr_valid(uptr shadow_addr) {
  return (uptr)shadow_addr >= ShadowAddr() && (uptr)shadow_addr < OriginAddr();
}

inline bool has_valid_shadow_addr(const void *ptr) {
  const dfsan_label *ptr_s = shadow_for(ptr);
  return is_shadow_addr_valid((uptr)ptr_s);
}

}  // namespace __dfsan

#endif  // DFSAN_H