/*
* Copyright (C) 2014 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef ART_LIBELFFILE_ELF_ELF_UTILS_H_
#define ART_LIBELFFILE_ELF_ELF_UTILS_H_
#include <elf.h>
#include <sys/cdefs.h>
#include <android-base/logging.h>
namespace art {
struct ElfTypes32 {
typedef Elf32_Addr Addr;
typedef Elf32_Off Off;
typedef Elf32_Half Half;
typedef Elf32_Word Word;
typedef Elf32_Sword Sword;
typedef Elf32_Ehdr Ehdr;
typedef Elf32_Shdr Shdr;
typedef Elf32_Sym Sym;
typedef Elf32_Rel Rel;
typedef Elf32_Rela Rela;
typedef Elf32_Phdr Phdr;
typedef Elf32_Dyn Dyn;
};
struct ElfTypes64 {
typedef Elf64_Addr Addr;
typedef Elf64_Off Off;
typedef Elf64_Half Half;
typedef Elf64_Word Word;
typedef Elf64_Sword Sword;
typedef Elf64_Xword Xword;
typedef Elf64_Sxword Sxword;
typedef Elf64_Ehdr Ehdr;
typedef Elf64_Shdr Shdr;
typedef Elf64_Sym Sym;
typedef Elf64_Rel Rel;
typedef Elf64_Rela Rela;
typedef Elf64_Phdr Phdr;
typedef Elf64_Dyn Dyn;
};
#define ELF_ST_BIND(x) ((x) >> 4)
#define ELF_ST_TYPE(x) ((x) & 0xf)
// Architecture dependent flags for the ELF header.
#define EF_ARM_EABI_VER5 0x05000000
#define EF_MIPS_ABI_O32 0x00001000
#define EF_MIPS_ARCH_32R2 0x70000000
#define EF_MIPS_ARCH_32R6 0x90000000
#define EF_MIPS_ARCH_64R6 0xa0000000
#define EI_ABIVERSION 8
#define EM_ARM 40
#define EF_MIPS_NOREORDER 1
#define STV_DEFAULT 0
#define EM_AARCH64 183
#define DT_BIND_NOW 24
#define DT_INIT_ARRAY 25
#define DT_FINI_ARRAY 26
#define DT_INIT_ARRAYSZ 27
#define DT_FINI_ARRAYSZ 28
#define DT_RUNPATH 29
#define DT_FLAGS 30
/* MIPS dependent d_tag field for Elf32_Dyn. */
#define DT_MIPS_RLD_VERSION 0x70000001 /* Runtime Linker Interface ID */
#define DT_MIPS_TIME_STAMP 0x70000002 /* Timestamp */
#define DT_MIPS_ICHECKSUM 0x70000003 /* Cksum of ext. str. and com. sizes */
#define DT_MIPS_IVERSION 0x70000004 /* Version string (string tbl index) */
#define DT_MIPS_FLAGS 0x70000005 /* Flags */
#define DT_MIPS_BASE_ADDRESS 0x70000006 /* Segment base address */
#define DT_MIPS_CONFLICT 0x70000008 /* Adr of .conflict section */
#define DT_MIPS_LIBLIST 0x70000009 /* Address of .liblist section */
#define DT_MIPS_LOCAL_GOTNO 0x7000000a /* Number of local .GOT entries */
#define DT_MIPS_CONFLICTNO 0x7000000b /* Number of .conflict entries */
#define DT_MIPS_LIBLISTNO 0x70000010 /* Number of .liblist entries */
#define DT_MIPS_SYMTABNO 0x70000011 /* Number of .dynsym entries */
#define DT_MIPS_UNREFEXTNO 0x70000012 /* First external DYNSYM */
#define DT_MIPS_GOTSYM 0x70000013 /* First GOT entry in .dynsym */
#define DT_MIPS_HIPAGENO 0x70000014 /* Number of GOT page table entries */
#define DT_MIPS_RLD_MAP 0x70000016 /* Address of debug map pointer */
// Patching section type
#define SHT_OAT_PATCH SHT_LOUSER
static inline void SetBindingAndType(Elf32_Sym* sym, unsigned char b, unsigned char t) {
sym->st_info = (b << 4) + (t & 0x0f);
}
static inline bool IsDynamicSectionPointer(Elf32_Word d_tag, Elf32_Word e_machine) {
switch (d_tag) {
// case 1: well known d_tag values that imply Elf32_Dyn.d_un contains an address in d_ptr
case DT_PLTGOT:
case DT_HASH:
case DT_STRTAB:
case DT_SYMTAB:
case DT_RELA:
case DT_INIT:
case DT_FINI:
case DT_REL:
case DT_DEBUG:
case DT_JMPREL: {
return true;
}
// d_val or ignored values
case DT_NULL:
case DT_NEEDED:
case DT_PLTRELSZ:
case DT_RELASZ:
case DT_RELAENT:
case DT_STRSZ:
case DT_SYMENT:
case DT_SONAME:
case DT_RPATH:
case DT_SYMBOLIC:
case DT_RELSZ:
case DT_RELENT:
case DT_PLTREL:
case DT_TEXTREL:
case DT_BIND_NOW:
case DT_INIT_ARRAYSZ:
case DT_FINI_ARRAYSZ:
case DT_RUNPATH:
case DT_FLAGS: {
return false;
}
// boundary values that should not be used
case DT_ENCODING:
case DT_LOOS:
case DT_HIOS:
case DT_LOPROC:
case DT_HIPROC: {
LOG(FATAL) << "Illegal d_tag value 0x" << std::hex << d_tag;
return false;
}
default: {
// case 2: "regular" DT_* ranges where even d_tag values imply an address in d_ptr
if ((DT_ENCODING < d_tag && d_tag < DT_LOOS)
|| (DT_LOOS < d_tag && d_tag < DT_HIOS)
|| (DT_LOPROC < d_tag && d_tag < DT_HIPROC)) {
// Special case for MIPS which breaks the regular rules between DT_LOPROC and DT_HIPROC
if (e_machine == EM_MIPS) {
switch (d_tag) {
case DT_MIPS_RLD_VERSION:
case DT_MIPS_TIME_STAMP:
case DT_MIPS_ICHECKSUM:
case DT_MIPS_IVERSION:
case DT_MIPS_FLAGS:
case DT_MIPS_LOCAL_GOTNO:
case DT_MIPS_CONFLICTNO:
case DT_MIPS_LIBLISTNO:
case DT_MIPS_SYMTABNO:
case DT_MIPS_UNREFEXTNO:
case DT_MIPS_GOTSYM:
case DT_MIPS_HIPAGENO: {
return false;
}
case DT_MIPS_BASE_ADDRESS:
case DT_MIPS_CONFLICT:
case DT_MIPS_LIBLIST:
case DT_MIPS_RLD_MAP: {
return true;
}
default: {
LOG(FATAL) << "Unknown MIPS d_tag value 0x" << std::hex << d_tag;
return false;
}
}
} else if ((d_tag % 2) == 0) {
return true;
} else {
return false;
}
} else {
LOG(FATAL) << "Unknown d_tag value 0x" << std::hex << d_tag;
return false;
}
}
}
}
} // namespace art
#endif // ART_LIBELFFILE_ELF_ELF_UTILS_H_