compute-runtime/shared/source/device_binary_format/elf/elf_decoder.cpp

90 lines
3.7 KiB
C++

/*
* Copyright (C) 2020 Intel Corporation
*
* SPDX-License-Identifier: MIT
*
*/
#include "device_binary_format/elf/elf_decoder.h"
#include "helpers/ptr_math.h"
#include <string.h>
namespace NEO {
namespace Elf {
template <ELF_IDENTIFIER_CLASS NumBits>
const ElfFileHeader<NumBits> *decodeElfFileHeader(const ArrayRef<const uint8_t> binary) {
if (binary.size() < sizeof(ElfFileHeader<NumBits>)) {
return nullptr;
}
const ElfFileHeader<NumBits> *header = reinterpret_cast<const ElfFileHeader<NumBits> *>(binary.begin());
bool validHeader = (header->identity.magic[0] == elfMagic[0]);
validHeader &= (header->identity.magic[1] == elfMagic[1]);
validHeader &= (header->identity.magic[2] == elfMagic[2]);
validHeader &= (header->identity.magic[3] == elfMagic[3]);
validHeader &= (header->identity.eClass == NumBits);
return validHeader ? header : nullptr;
}
template const ElfFileHeader<EI_CLASS_32> *decodeElfFileHeader<EI_CLASS_32>(const ArrayRef<const uint8_t>);
template const ElfFileHeader<EI_CLASS_64> *decodeElfFileHeader<EI_CLASS_64>(const ArrayRef<const uint8_t>);
template <ELF_IDENTIFIER_CLASS NumBits>
Elf<NumBits> decodeElf(const ArrayRef<const uint8_t> binary, std::string &outErrReason, std::string &outWarning) {
Elf<NumBits> ret = {};
ret.elfFileHeader = decodeElfFileHeader<NumBits>(binary);
if (nullptr == ret.elfFileHeader) {
outErrReason = "Invalid or missing ELF header";
return {};
}
if (ret.elfFileHeader->phOff + ret.elfFileHeader->phNum * ret.elfFileHeader->phEntSize > binary.size()) {
outErrReason = "Out of bounds program headers table";
return {};
}
if (ret.elfFileHeader->shOff + ret.elfFileHeader->shNum * ret.elfFileHeader->shEntSize > binary.size()) {
outErrReason = "Out of bounds section headers table";
return {};
}
const ElfProgramHeader<NumBits> *programHeader = reinterpret_cast<const ElfProgramHeader<NumBits> *>(binary.begin() + ret.elfFileHeader->phOff);
for (decltype(ret.elfFileHeader->phNum) i = 0; i < ret.elfFileHeader->phNum; ++i) {
if (programHeader->offset + programHeader->fileSz > binary.size()) {
outErrReason = "Out of bounds program header offset/filesz, program header idx : " + std::to_string(i);
return {};
}
ArrayRef<const uint8_t> data(binary.begin() + programHeader->offset, static_cast<size_t>(programHeader->fileSz));
ret.programHeaders.push_back({programHeader, data});
programHeader = ptrOffset(programHeader, ret.elfFileHeader->phEntSize);
}
const ElfSectionHeader<NumBits> *sectionHeader = reinterpret_cast<const ElfSectionHeader<NumBits> *>(binary.begin() + ret.elfFileHeader->shOff);
for (decltype(ret.elfFileHeader->shNum) i = 0; i < ret.elfFileHeader->shNum; ++i) {
ArrayRef<const uint8_t> data;
if (SHT_NOBITS != sectionHeader->type) {
if (sectionHeader->offset + sectionHeader->size > binary.size()) {
outErrReason = "Out of bounds section header offset/size, section header idx : " + std::to_string(i);
return {};
}
data = ArrayRef<const uint8_t>(binary.begin() + sectionHeader->offset, static_cast<size_t>(sectionHeader->size));
}
ret.sectionHeaders.push_back({sectionHeader, data});
sectionHeader = ptrOffset(sectionHeader, ret.elfFileHeader->shEntSize);
}
return ret;
}
template Elf<EI_CLASS_32> decodeElf<EI_CLASS_32>(const ArrayRef<const uint8_t>, std::string &, std::string &);
template Elf<EI_CLASS_64> decodeElf<EI_CLASS_64>(const ArrayRef<const uint8_t>, std::string &, std::string &);
} // namespace Elf
} // namespace NEO