C++ MemoryRegion类代码示例

void ELFObjectWriter::emitSectionHeader(const Module& pModule,
                                        const LinkerConfig& pConfig,
                                        MemoryArea& pOutput) const
{
  typedef typename ELFSizeTraits<SIZE>::Shdr ElfXX_Shdr;

  // emit section header
  unsigned int sectNum = pModule.size();
  unsigned int header_size = sizeof(ElfXX_Shdr) * sectNum;
  MemoryRegion* region = pOutput.request(getLastStartOffset<SIZE>(pModule),
                                         header_size);
  ElfXX_Shdr* shdr = (ElfXX_Shdr*)region->start();

  // Iterate the SectionTable in LDContext
  unsigned int sectIdx = 0;
  unsigned int shstridx = 0; // NULL section has empty name
  for (; sectIdx < sectNum; ++sectIdx) {
    const LDSection *ld_sect   = pModule.getSectionTable().at(sectIdx);
    shdr[sectIdx].sh_name      = shstridx;
    shdr[sectIdx].sh_type      = ld_sect->type();
    shdr[sectIdx].sh_flags     = ld_sect->flag();
    shdr[sectIdx].sh_addr      = ld_sect->addr();
    shdr[sectIdx].sh_offset    = ld_sect->offset();
    shdr[sectIdx].sh_size      = ld_sect->size();
    shdr[sectIdx].sh_addralign = ld_sect->align();
    shdr[sectIdx].sh_entsize   = getSectEntrySize<SIZE>(*ld_sect);
    shdr[sectIdx].sh_link      = getSectLink(*ld_sect, pConfig);
    shdr[sectIdx].sh_info      = getSectInfo(*ld_sect);

    // adjust strshidx
    shstridx += ld_sect->name().size() + 1;
  }
}

uint64_t NyuziGNULDBackend::emitSectionData(const LDSection& pSection,
                                              MemoryRegion& pRegion) const
{
  assert(pRegion.size() && "Size of MemoryRegion is zero!");

  return pRegion.size();
}

/// isMyFormat
bool ELFDynObjReader::isMyFormat(Input &pInput, bool &pContinue) const
{
    assert(pInput.hasMemArea());

    // Don't warning about the frequently requests.
    // MemoryArea has a list of cache to handle this.
    size_t hdr_size = m_pELFReader->getELFHeaderSize();
    if (pInput.memArea()->size() < hdr_size)
        return false;

    MemoryRegion* region = pInput.memArea()->request(pInput.fileOffset(),
                           hdr_size);

    uint8_t* ELF_hdr = region->start();
    bool result = true;
    if (!m_pELFReader->isELF(ELF_hdr)) {
        pContinue = true;
        result = false;
    } else if (Input::DynObj != m_pELFReader->fileType(ELF_hdr)) {
        pContinue = true;
        result = false;
    } else if (!m_pELFReader->isMyEndian(ELF_hdr)) {
        pContinue = false;
        result = false;
    } else if (!m_pELFReader->isMyMachine(ELF_hdr)) {
        pContinue = false;
        result = false;
    }
    pInput.memArea()->release(region);
    return result;
}

/*
* EMSA1 BSI Encode Operation
*/
SecureVector<byte> EMSA1_BSI::encoding_of(const MemoryRegion<byte>& msg,
                                          u32bit output_bits,
                                          RandomNumberGenerator&)
   {
   if(msg.size() != hash_ptr()->OUTPUT_LENGTH)
      throw Encoding_Error("EMSA1_BSI::encoding_of: Invalid size for input");

   if(8*msg.size() <= output_bits)
      return msg;

   throw Encoding_Error("EMSA1_BSI::encoding_of: max key input size exceeded");
   }

uint64_t X86GNULDBackend::emitSectionData(const LDSection& pSection,
                                          MemoryRegion& pRegion) const
{
  assert(pRegion.size() && "Size of MemoryRegion is zero!");

  const ELFFileFormat* FileFormat = getOutputFormat();
  assert(FileFormat &&
         "ELFFileFormat is NULL in X86GNULDBackend::emitSectionData!");

  unsigned int EntrySize = 0;
  uint64_t RegionSize = 0;

  if (&pSection == &(FileFormat->getPLT())) {
    assert(m_pPLT && "emitSectionData failed, m_pPLT is NULL!");

    unsigned char* buffer = pRegion.getBuffer();

    m_pPLT->applyPLT0();
    m_pPLT->applyPLT1();
    X86PLT::iterator it = m_pPLT->begin();
    unsigned int plt0_size = llvm::cast<PLTEntryBase>((*it)).size();

    memcpy(buffer, llvm::cast<PLTEntryBase>((*it)).getValue(), plt0_size);
    RegionSize += plt0_size;
    ++it;

    PLTEntryBase* plt1 = 0;
    X86PLT::iterator ie = m_pPLT->end();
    while (it != ie) {
      plt1 = &(llvm::cast<PLTEntryBase>(*it));
      EntrySize = plt1->size();
      memcpy(buffer + RegionSize, plt1->getValue(), EntrySize);
      RegionSize += EntrySize;
      ++it;
    }
  }

  else if (&pSection == &(FileFormat->getGOT())) {
    RegionSize += emitGOTSectionData(pRegion);
  }

  else if (&pSection == &(FileFormat->getGOTPLT())) {
    RegionSize += emitGOTPLTSectionData(pRegion, FileFormat);
  }

  else {
    fatal(diag::unrecognized_output_sectoin)
            << pSection.name()
            << "[email protected]";
  }
  return RegionSize;
}

/*
* Split up and process handshake messages
*/
void TLS_Server::read_handshake(byte rec_type,
                                const MemoryRegion<byte>& rec_buf)
   {
   if(rec_type == HANDSHAKE)
      {
      if(!state)
         state = new Handshake_State;
      state->queue.write(&rec_buf[0], rec_buf.size());
      }

   while(true)
      {
      Handshake_Type type = HANDSHAKE_NONE;
      SecureVector<byte> contents;

      if(rec_type == HANDSHAKE)
         {
         if(state->queue.size() >= 4)
            {
            byte head[4] = { 0 };
            state->queue.peek(head, 4);

            const size_t length = make_u32bit(0, head[1], head[2], head[3]);

            if(state->queue.size() >= length + 4)
               {
               type = static_cast<Handshake_Type>(head[0]);
               contents.resize(length);
               state->queue.read(head, 4);
               state->queue.read(&contents[0], contents.size());
               }
            }
         }
      else if(rec_type == CHANGE_CIPHER_SPEC)
         {
         if(state->queue.size() == 0 && rec_buf.size() == 1 && rec_buf[0] == 1)
            type = HANDSHAKE_CCS;
         else
            throw Decoding_Error("Malformed ChangeCipherSpec message");
         }
      else
         throw Decoding_Error("Unknown message type in handshake processing");

      if(type == HANDSHAKE_NONE)
         break;

      process_handshake_msg(type, contents);

      if(type == HANDSHAKE_CCS || !state)
         break;
      }
   }

/// emitShStrTab - emit section string table
void
ELFObjectWriter::emitShStrTab(const LDSection& pShStrTab,
                              const Module& pModule,
                              MemoryArea& pOutput)
{
  // write out data
  MemoryRegion* region = pOutput.request(pShStrTab.offset(), pShStrTab.size());
  unsigned char* data = region->start();
  size_t shstrsize = 0;
  Module::const_iterator section, sectEnd = pModule.end();
  for (section = pModule.begin(); section != sectEnd; ++section) {
    strcpy((char*)(data + shstrsize), (*section)->name().data());
    shstrsize += (*section)->name().size() + 1;
  }
}

/// isThinArchive
bool GNUArchiveReader::isThinArchive(Input& pInput) const
{
  assert(pInput.hasMemArea());
  MemoryRegion* region = pInput.memArea()->request(pInput.fileOffset(),
                                                   Archive::MAGIC_LEN);
  const char* str = reinterpret_cast<const char*>(region->getBuffer());

  bool result = false;
  assert(NULL != str);
  if (isThinArchive(str))
    result = true;

  pInput.memArea()->release(region);
  return result;
}

/// emit
void ELFDynamic::emit(const LDSection& pSection, MemoryRegion& pRegion) const
{
  if (pRegion.size() < pSection.size()) {
    llvm::report_fatal_error(llvm::Twine("the given memory is smaller") +
                             llvm::Twine(" than the section's demaind.\n"));
  }

  uint8_t* address = (uint8_t*)pRegion.begin();
  EntryListType::const_iterator entry, entryEnd = m_NeedList.end();
  for (entry = m_NeedList.begin(); entry != entryEnd; ++entry)
    address += (*entry)->emit(address);

  entryEnd = m_EntryList.end();
  for (entry = m_EntryList.begin(); entry != entryEnd; ++entry)
    address += (*entry)->emit(address);
}

//! Returns true if the address filter overlaps \a region.
bool StExecutableImage::AddressFilter::matchesMemoryRegion(const MemoryRegion &region) const
{
    uint32_t firstByte = region.m_address;   // first byte occupied by this region
    uint32_t lastByte = region.endAddress(); // last used byte in this region
    return (firstByte >= m_fromAddress && firstByte <= m_toAddress) ||
           (lastByte >= m_fromAddress && lastByte <= m_toAddress);
}

/*
* Generate one of the Sboxes
*/
void Blowfish::generate_sbox(MemoryRegion<u32bit>& box,
                             u32bit& L, u32bit& R,
                             const byte salt[16],
                             size_t salt_off) const
   {
   const u32bit* S1 = &S[0];
   const u32bit* S2 = &S[256];
   const u32bit* S3 = &S[512];
   const u32bit* S4 = &S[768];

   for(size_t i = 0; i != box.size(); i += 2)
      {
      L ^= load_be<u32bit>(salt, (i + salt_off) % 4);
      R ^= load_be<u32bit>(salt, (i + salt_off + 1) % 4);

      for(size_t j = 0; j != 16; j += 2)
         {
         L ^= P[j];
         R ^= ((S1[get_byte(0, L)]  + S2[get_byte(1, L)]) ^
                S3[get_byte(2, L)]) + S4[get_byte(3, L)];

         R ^= P[j+1];
         L ^= ((S1[get_byte(0, R)]  + S2[get_byte(1, R)]) ^
                S3[get_byte(2, R)]) + S4[get_byte(3, R)];
         }

      u32bit T = R; R = L ^ P[16]; L = T ^ P[17];
      box[i] = L;
      box[i+1] = R;
      }
   }

static void readSymbolTableEntries(Archive& pArchive, MemoryRegion& pMemRegion)
{
  typedef typename SizeTraits<SIZE>::Offset Offset;

  const Offset* data = reinterpret_cast<const Offset*>(pMemRegion.getBuffer());

  // read the number of symbols
  Offset number = 0;
  if (llvm::sys::IsLittleEndianHost)
    number = mcld::bswap<SIZE>(*data);
  else
    number = *data;

  // set up the pointers for file offset and name offset
  ++data;
  const char* name = reinterpret_cast<const char*>(data + number);

  // add the archive symbols
  for (Offset i = 0; i < number; ++i) {
    if (llvm::sys::IsLittleEndianHost)
      pArchive.addSymbol(name, mcld::bswap<SIZE>(*data));
    else
      pArchive.addSymbol(name, *data);
    name += strlen(name) + 1;
    ++data;
  }
}

// SetUp() will be called immediately before each test.
void ELFReaderTest::SetUp()
{
  Path path(TOPDIR);
  path.append("unittests/test_x86_64.o");

  m_pInput = m_pIRBuilder->ReadInput("test_x86_64", path);
  ASSERT_TRUE(NULL!=m_pInput);

  ASSERT_TRUE(m_pInput->hasMemArea());
  size_t hdr_size = m_pELFReader->getELFHeaderSize();
  MemoryRegion* region = m_pInput->memArea()->request(m_pInput->fileOffset(),
                                                    hdr_size);
  uint8_t* ELF_hdr = region->start();
  bool shdr_result = m_pELFReader->readSectionHeaders(*m_pInput, ELF_hdr);
  m_pInput->memArea()->release(region);
  ASSERT_TRUE(shdr_result);
}

/// readDSO
bool ELFDynObjReader::readDSO(Input& pInput)
{
  assert(pInput.hasMemArea());

  size_t hdr_size = m_pELFReader->getELFHeaderSize();
  MemoryRegion* region = pInput.memArea()->request(pInput.fileOffset(),
                                                   hdr_size);
  uint8_t* ELF_hdr = region->start();

  bool shdr_result = m_pELFReader->readSectionHeaders(pInput, m_Linker, ELF_hdr);
  pInput.memArea()->release(region);

  // read .dynamic to get the correct SONAME
  bool dyn_result = m_pELFReader->readDynamic(pInput);

  return (shdr_result && dyn_result);
}

SecureVector<byte> rfc3394_keyunwrap(const MemoryRegion<byte>& key,
                                     const SymmetricKey& kek,
                                     Algorithm_Factory& af)
   {
   if(key.size() < 16 || key.size() % 8 != 0)
      throw std::invalid_argument("Bad input key size for NIST key unwrap");

   std::auto_ptr<BlockCipher> aes(make_aes(kek.length(), af));
   aes->set_key(kek);

   const size_t n = (key.size() - 8) / 8;

   SecureVector<byte> R(n * 8);
   SecureVector<byte> A(16);

   for(size_t i = 0; i != 8; ++i)
      A[i] = key[i];

   copy_mem(&R[0], key.begin() + 8, key.size() - 8);

   for(size_t j = 0; j <= 5; ++j)
      {
      for(size_t i = n; i != 0; --i)
         {
         const u32bit t = (5 - j) * n + i;

         byte t_buf[4] = { 0 };
         store_be(t, t_buf);

         xor_buf(&A[4], &t_buf[0], 4);

         copy_mem(&A[8], &R[8*(i-1)], 8);

         aes->decrypt(&A[0]);

         copy_mem(&R[8*(i-1)], &A[8], 8);
         }
      }

   if(load_be<u64bit>(&A[0], 0) != 0xA6A6A6A6A6A6A6A6)
      throw Integrity_Failure("NIST key unwrap failed");

   return R;
   }