Esempio n. 1
0
TEST_F( ELFReaderTest, read_symbol_and_rela )
{
  ASSERT_TRUE(m_pInput->hasMemArea());
  ASSERT_TRUE(m_pInput->hasContext());
  m_pInput->setType(Input::Object);

  // -- read symbols
  LDSection* symtab_shdr = m_pInput->context()->getSection(".symtab");
  ASSERT_TRUE(NULL!=symtab_shdr);

  LDSection* strtab_shdr = symtab_shdr->getLink();
  ASSERT_TRUE(NULL!=strtab_shdr);

  MemoryRegion* symtab_region = m_pInput->memArea()->request(
                         m_pInput->fileOffset() + symtab_shdr->offset(),
                         symtab_shdr->size());

  MemoryRegion* strtab_region = m_pInput->memArea()->request(
                         m_pInput->fileOffset() + strtab_shdr->offset(),
                         strtab_shdr->size());
  char* strtab = reinterpret_cast<char*>(strtab_region->start());
  bool result = m_pELFReader->readSymbols(*m_pInput, *m_pIRBuilder,
                                          *symtab_region, strtab);
  ASSERT_TRUE(result);
  ASSERT_EQ("hello.c", std::string(m_pInput->context()->getSymbol(1)->name()));
  ASSERT_EQ("puts", std::string(m_pInput->context()->getSymbol(10)->name()));
  ASSERT_TRUE(NULL==m_pInput->context()->getSymbol(11));
  m_pInput->memArea()->release(symtab_region);
  m_pInput->memArea()->release(strtab_region);

  // -- read relocations
  MemoryArea* mem = m_pInput->memArea();
  LDContext::sect_iterator rs = m_pInput->context()->relocSectBegin();
  ASSERT_TRUE(rs!=m_pInput->context()->relocSectEnd());
  ASSERT_EQ(".rela.text", (*rs)->name());

  uint64_t offset = m_pInput->fileOffset() + (*rs)->offset();
  uint64_t size = (*rs)->size();
  MemoryRegion* region = mem->request(offset, size);
  IRBuilder::CreateRelocData(**rs); /// create relocation data for the header

  ASSERT_EQ(llvm::ELF::SHT_RELA, (*rs)->type());
  ASSERT_TRUE(m_pELFReader->readRela(*m_pInput, **rs, *region));
  mem->release(region);

  const RelocData::RelocationListType &rRelocs =
                          (*rs)->getRelocData()->getRelocationList();
  RelocData::const_iterator rReloc = rRelocs.begin();
  ASSERT_EQ(2, rRelocs.size());
  ASSERT_TRUE(rRelocs.end()!=rReloc);
  ++rReloc; /// test rRelocs[1]
  ASSERT_EQ("puts", std::string(rReloc->symInfo()->name()));
  ASSERT_EQ(llvm::ELF::R_X86_64_PC32, rReloc->type());
  ASSERT_EQ(0x0, rReloc->symValue());
  ASSERT_EQ(-0x4, rReloc->addend());
}
Esempio n. 2
0
void EhFrameHdr::emitOutput<32>(MemoryArea& pOutput)
{
    MemoryRegion* ehframehdr_region =
        pOutput.request(m_EhFrameHdr.offset(), m_EhFrameHdr.size());

    MemoryRegion* ehframe_region =
        pOutput.request(m_EhFrame.offset(),
                        m_EhFrame.size());

    uint8_t* data = (uint8_t*)ehframehdr_region->start();
    // version
    data[0] = 1;
    // eh_frame_ptr_enc
    data[1] = DW_EH_PE_pcrel | DW_EH_PE_sdata4;

    // eh_frame_ptr
    uint32_t* eh_frame_ptr = (uint32_t*)(data + 4);
    *eh_frame_ptr = m_EhFrame.addr() - (m_EhFrameHdr.addr() + 4);

    // fde_count
    uint32_t* fde_count = (uint32_t*)(data + 8);
    if (m_EhFrame.hasEhFrame())
        *fde_count = 0;
    else
        *fde_count = m_EhFrame.getEhFrame()->numOfFDEs();

    if (0 != *fde_count) {
        // fde_count_enc
        data[2] = DW_EH_PE_udata4;
        // table_enc
        data[3] = DW_EH_PE_datarel | DW_EH_PE_sdata4;

    }
    else {
        // fde_count_enc
        data[2] = DW_EH_PE_omit;
        // table_enc
        data[3] = DW_EH_PE_omit;
    }

    if (0 != *fde_count) {

        // prepare the binary search table
        typedef std::vector<bit32::Entry> SearchTableType;
        SearchTableType search_table;
        MemoryRegion* ehframe_region =
            pOutput.request(m_EhFrame.offset(), m_EhFrame.size());
        EhFrame::const_fde_iterator fde, fde_end = m_EhFrame.getEhFrame()->fde_end();
        for(fde = m_EhFrame.getEhFrame()->fde_begin(); fde != fde_end; ++fde) {
            assert(*fde != NULL);
            SizeTraits<32>::Offset offset;
            SizeTraits<32>::Address fde_pc;
            SizeTraits<32>::Address fde_addr;
            offset = (*fde)->getOffset();
            fde_pc = computePCBegin(**fde, *ehframe_region);
            fde_addr = m_EhFrame.addr() + offset;
            search_table.push_back(std::make_pair(fde_pc, fde_addr));
        }
        pOutput.release(ehframe_region);

        std::sort(search_table.begin(), search_table.end(), bit32::EntryCompare);

        // write out the binary search table
        uint32_t* bst = (uint32_t*)(data + 12);
        SearchTableType::const_iterator entry, entry_end = search_table.end();
        size_t id = 0;
        for (entry = search_table.begin(); entry != entry_end; ++entry) {
            bst[id++] = (*entry).first - m_EhFrameHdr.addr();
            bst[id++] = (*entry).second - m_EhFrameHdr.addr();
        }
    }
    pOutput.release(ehframehdr_region);
    pOutput.release(ehframe_region);
}