int main(int argc, char *argv[]){ elfHeader_t elfHeader; FILE *elf, *bin; uint32_t numBytesRead, i; if(argc != 2){ printf("Please specify exactly one input elf file\n"); exit(-1); } if((elf = fopen(argv[1],"rb")) == NULL){ printf("Could not open %s\n", argv[1]); exit(-2); } // // FIXME // The file name should match the input file excepting // for the extension. // char *outputFileName = (char *)malloc(strlen(argv[1]) + 4); char *ptr; if(ptr = strrchr(argv[1], '.')) *ptr = '\0'; sprintf(outputFileName,"%s.img",argv[1]); if((bin = fopen(outputFileName,"wb")) == NULL){ printf("Could not open file for writing\n"); exit(-3); } parseElfHeader(elf,&elfHeader); if(elfHeader.e_type != ET_EXEC){ printf("Invalid ELF: Non-executable image\n"); exit(-4); } if(elfHeader.e_machine != EM_ARM){ printf("Invalid ELF: Not ARM executable\n"); exit(-5); } if(elfHeader.e_phoff == 0){ printf("Invalid ELF: Process image cannot be created\n"); exit(-6); } for(i=0; i<elfHeader.e_phnum; i++){ programHeader_t *programHeader = (programHeader_t *)malloc(sizeof(programHeader_t)); parseProgramHeader(elf, programHeader); uint32_t inst; fseek(elf, programHeader->p_paddr, SEEK_SET); for(i=0; i<programHeader->p_filesz; i++){ fread(&inst,1,4,elf); fwrite(&inst,1,4,bin); } } fclose(elf); fclose(bin); }
ElfReader::Result ElfReader::readIt() { if (!m_elfData.sectionHeaders.isEmpty()) return Ok; if (!m_elfData.programHeaders.isEmpty()) return Ok; ElfMapper mapper(this); if (!mapper.map()) return Corrupt; const quint64 fdlen = mapper.fdlen; if (fdlen < 64) { m_errorString = QStringLiteral("'%1' is not an ELF object (file too small)").arg(QDir::toNativeSeparators(m_binary)); return NotElf; } if (strncmp(mapper.start, "\177ELF", 4) != 0) { m_errorString = QStringLiteral("'%1' is not an ELF object").arg(QDir::toNativeSeparators(m_binary)); return NotElf; } // 32 or 64 bit m_elfData.elfclass = ElfClass(mapper.start[4]); const bool is64Bit = m_elfData.elfclass == Elf_ELFCLASS64; if (m_elfData.elfclass != Elf_ELFCLASS32 && m_elfData.elfclass != Elf_ELFCLASS64) { m_errorString = msgInvalidElfObject(m_binary, QStringLiteral("odd cpu architecture")); return Corrupt; } // int bits = (data[4] << 5); // If you remove this check to read ELF objects of a different arch, // please make sure you modify the typedefs // to match the _plugin_ architecture. // if ((sizeof(void*) == 4 && bits != 32) // || (sizeof(void*) == 8 && bits != 64)) { // if (errorString) // *errorString = QLibrary::QStringLiteral("'%1' is an invalid ELF object (%2)") // .arg(m_binary).arg(QLatin1String("wrong cpu architecture")); // return Corrupt; // } // Read Endianhness. m_elfData.endian = ElfEndian(mapper.ustart[5]); if (m_elfData.endian != Elf_ELFDATA2LSB && m_elfData.endian != Elf_ELFDATA2MSB) { m_errorString = msgInvalidElfObject(m_binary, QStringLiteral("odd endianness")); return Corrupt; } const uchar *data = mapper.ustart + 16; // e_ident m_elfData.elftype = ElfType(getHalfWord(data, m_elfData)); m_elfData.elfmachine = ElfMachine(getHalfWord(data, m_elfData)); /* e_version = */ getWord(data, m_elfData); m_elfData.entryPoint = getAddress(data, m_elfData); quint64 e_phoff = getOffset(data, m_elfData); quint64 e_shoff = getOffset(data, m_elfData); /* e_flags = */ getWord(data, m_elfData); quint32 e_shsize = getHalfWord(data, m_elfData); if (e_shsize > fdlen) { m_errorString = msgInvalidElfObject(m_binary, QStringLiteral("unexpected e_shsize")); return Corrupt; } quint32 e_phentsize = getHalfWord(data, m_elfData); if (e_phentsize != (is64Bit ? 56 : 32)) { m_errorString = msgInvalidElfObject(m_binary, QStringLiteral("invalid structure")); return ElfReader::Corrupt; } quint32 e_phnum = getHalfWord(data, m_elfData); quint32 e_shentsize = getHalfWord(data, m_elfData); if (e_shentsize % 4) { m_errorString = msgInvalidElfObject(m_binary, QStringLiteral("unexpected e_shentsize")); return Corrupt; } quint32 e_shnum = getHalfWord(data, m_elfData); quint32 e_shtrndx = getHalfWord(data, m_elfData); if (data != mapper.ustart + (is64Bit ? 64 : 52)) { m_errorString = msgInvalidElfObject(m_binary, QStringLiteral("unexpected e_phentsize")); return ElfReader::Corrupt; } if (quint64(e_shnum) * e_shentsize > fdlen) { const QString reason = QStringLiteral("announced %1 sections, each %2 bytes, exceed file size").arg(e_shnum).arg(e_shentsize); m_errorString = msgInvalidElfObject(m_binary, reason); return Corrupt; } quint64 soff = e_shoff + e_shentsize * e_shtrndx; // if ((soff + e_shentsize) > fdlen || soff % 4 || soff == 0) { // m_errorString = QLibrary::QStringLiteral("'%1' is an invalid ELF object (%2)") // .arg(m_binary) // .arg(QLatin1String("shstrtab section header seems to be at %1")) // .arg(QString::number(soff, 16)); // return Corrupt; // } if (e_shoff) { ElfSectionHeader strtab; parseSectionHeader(mapper.ustart + soff, &strtab, m_elfData); const quint64 stringTableFileOffset = strtab.offset; if (quint32(stringTableFileOffset + e_shentsize) >= fdlen || stringTableFileOffset == 0) { const QString reason = QStringLiteral("string table seems to be at 0x%1").arg(soff, 0, 16); m_errorString = msgInvalidElfObject(m_binary, reason); return Corrupt; } for (quint32 i = 0; i < e_shnum; ++i) { const uchar *s = mapper.ustart + e_shoff + i * e_shentsize; ElfSectionHeader sh; parseSectionHeader(s, &sh, m_elfData); if (stringTableFileOffset + sh.index > fdlen) { const QString reason = QStringLiteral("section name %1 of %2 behind end of file") .arg(i).arg(e_shnum); m_errorString = msgInvalidElfObject(m_binary, reason); return Corrupt; } sh.name = mapper.start + stringTableFileOffset + sh.index; if (sh.name == ".gdb_index") { m_elfData.symbolsType = FastSymbols; } else if (sh.name == ".debug_info") { m_elfData.symbolsType = PlainSymbols; } else if (sh.name == ".gnu_debuglink") { m_elfData.debugLink = QByteArray(mapper.start + sh.offset); m_elfData.symbolsType = LinkedSymbols; } else if (sh.name == ".note.gnu.build-id") { m_elfData.symbolsType = BuildIdSymbols; if (sh.size > 16) m_elfData.buildId = QByteArray(mapper.start + sh.offset + 16, sh.size - 16).toHex(); } m_elfData.sectionHeaders.append(sh); } } if (e_phoff) { for (quint32 i = 0; i < e_phnum; ++i) { const uchar *s = mapper.ustart + e_phoff + i * e_phentsize; ElfProgramHeader ph; parseProgramHeader(s, &ph, m_elfData); m_elfData.programHeaders.append(ph); } } return Ok; }