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/*
* Copyright (C) 2012 The Android Open Source Project
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef LINKER_PHDR_H
#define LINKER_PHDR_H
/* Declarations related to the ELF program header table and segments.
*
* The design goal is to provide an API that is as close as possible
* to the ELF spec, and does not depend on linker-specific data
* structures (e.g. the exact layout of struct soinfo).
*/
#include "linker.h"
class ElfReader {
public:
ElfReader(const char* name, int fd, off64_t file_offset);
~ElfReader();
bool Load(const android_dlextinfo* extinfo);
size_t phdr_count() { return phdr_num_; }
ElfW(Addr) load_start() { return reinterpret_cast<ElfW(Addr)>(load_start_); }
size_t load_size() { return load_size_; }
ElfW(Addr) load_bias() { return load_bias_; }
const ElfW(Phdr)* loaded_phdr() { return loaded_phdr_; }
private:
bool ReadElfHeader();
bool VerifyElfHeader();
bool ReadProgramHeader();
bool ReserveAddressSpace(const android_dlextinfo* extinfo);
bool LoadSegments();
bool FindPhdr();
bool CheckPhdr(ElfW(Addr));
const char* name_;
int fd_;
off64_t file_offset_;
ElfW(Ehdr) header_;
size_t phdr_num_;
void* phdr_mmap_;
ElfW(Phdr)* phdr_table_;
ElfW(Addr) phdr_size_;
// First page of reserved address space.
void* load_start_;
// Size in bytes of reserved address space.
size_t load_size_;
// Load bias.
ElfW(Addr) load_bias_;
// Loaded phdr.
const ElfW(Phdr)* loaded_phdr_;
};
size_t phdr_table_get_load_size(const ElfW(Phdr)* phdr_table, size_t phdr_count,
ElfW(Addr)* min_vaddr = nullptr, ElfW(Addr)* max_vaddr = nullptr);
int phdr_table_protect_segments(const ElfW(Phdr)* phdr_table, size_t phdr_count, ElfW(Addr) load_bias);
int phdr_table_unprotect_segments(const ElfW(Phdr)* phdr_table, size_t phdr_count, ElfW(Addr) load_bias);
int phdr_table_protect_gnu_relro(const ElfW(Phdr)* phdr_table, size_t phdr_count, ElfW(Addr) load_bias);
int phdr_table_serialize_gnu_relro(const ElfW(Phdr)* phdr_table, size_t phdr_count, ElfW(Addr) load_bias,
int fd);
int phdr_table_map_gnu_relro(const ElfW(Phdr)* phdr_table, size_t phdr_count, ElfW(Addr) load_bias,
int fd);
#if defined(__arm__)
int phdr_table_get_arm_exidx(const ElfW(Phdr)* phdr_table, size_t phdr_count, ElfW(Addr) load_bias,
ElfW(Addr)** arm_exidx, unsigned* arm_exidix_count);
#endif
void phdr_table_get_dynamic_section(const ElfW(Phdr)* phdr_table, size_t phdr_count,
ElfW(Addr) load_bias, ElfW(Dyn)** dynamic,
ElfW(Word)* dynamic_flags);
#endif /* LINKER_PHDR_H */
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