183ad9df53
Add flags and a file descriptor to android_dlopen_ext() to allow writing the RELRO section of the loaded library to a file after relocation processing, and to allow mapping identical pages from the file over the top of relocated memory in another process. Explicitly comparing the pages is required in case a page contains a reference to a symbol defined in another library loaded at a random base address. Bug: 13005501 Change-Id: Ibb5b2d384edfaa5acf3e97a5f8b6115c10497a1e
107 lines
3.9 KiB
C++
107 lines
3.9 KiB
C++
/*
|
|
* 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);
|
|
~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_;
|
|
|
|
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 = NULL, ElfW(Addr)* max_vaddr = NULL);
|
|
|
|
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, size_t* dynamic_count, ElfW(Word)* dynamic_flags);
|
|
|
|
#endif /* LINKER_PHDR_H */
|