| /* |
| * Copyright (C) 2008 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_H_ |
| #define _LINKER_H_ |
| |
| #include <elf.h> |
| #include <link.h> |
| #include <unistd.h> |
| #include <android/dlext.h> |
| #include <sys/stat.h> |
| |
| #include "private/libc_logging.h" |
| #include "linked_list.h" |
| |
| // ARC MOD BEGIN |
| // For __nacl_irt_query_fn_t. |
| #if defined(HAVE_ARC) |
| #include <irt_syscalls.h> |
| #endif |
| // ARC MOD END |
| #define DL_ERR(fmt, x...) \ |
| do { \ |
| __libc_format_buffer(linker_get_error_buffer(), linker_get_error_buffer_size(), fmt, ##x); \ |
| /* If LD_DEBUG is set high enough, log every dlerror(3) message. */ \ |
| /* ARC MOD BEGIN */ \ |
| /* Use PRINT instead of DEBUG and remove unnecessary \n. */ \ |
| PRINT("%s", linker_get_error_buffer()); \ |
| /* ARC MOD END */ \ |
| } while (false) |
| |
| #define DL_WARN(fmt, x...) \ |
| do { \ |
| __libc_format_log(ANDROID_LOG_WARN, "linker", fmt, ##x); \ |
| __libc_format_fd(2, "WARNING: linker: "); \ |
| __libc_format_fd(2, fmt, ##x); \ |
| __libc_format_fd(2, "\n"); \ |
| } while (false) |
| |
| // ARC MOD BEGIN |
| // NaCl x86-64 is ILP32 but has ELF64 headers. |
| // #if defined(__LP64__) |
| #if defined(__LP64__) || (defined(__native_client__) && defined(__x86_64__)) |
| // ARC MOD END |
| #define ELFW(what) ELF64_ ## what |
| #else |
| #define ELFW(what) ELF32_ ## what |
| #endif |
| |
| // mips64 interprets Elf64_Rel structures' r_info field differently. |
| // bionic (like other C libraries) has macros that assume regular ELF files, |
| // but the dynamic linker needs to be able to load mips64 ELF files. |
| #if defined(__mips__) && defined(__LP64__) |
| #undef ELF64_R_SYM |
| #undef ELF64_R_TYPE |
| #undef ELF64_R_INFO |
| #define ELF64_R_SYM(info) (((info) >> 0) & 0xffffffff) |
| #define ELF64_R_SSYM(info) (((info) >> 32) & 0xff) |
| #define ELF64_R_TYPE3(info) (((info) >> 40) & 0xff) |
| #define ELF64_R_TYPE2(info) (((info) >> 48) & 0xff) |
| #define ELF64_R_TYPE(info) (((info) >> 56) & 0xff) |
| #endif |
| |
| // Returns the address of the page containing address 'x'. |
| #define PAGE_START(x) ((x) & PAGE_MASK) |
| |
| // Returns the offset of address 'x' in its page. |
| #define PAGE_OFFSET(x) ((x) & ~PAGE_MASK) |
| |
| // Returns the address of the next page after address 'x', unless 'x' is |
| // itself at the start of a page. |
| #define PAGE_END(x) PAGE_START((x) + (PAGE_SIZE-1)) |
| |
| #define FLAG_LINKED 0x00000001 |
| #define FLAG_EXE 0x00000004 // The main executable |
| #define FLAG_LINKER 0x00000010 // The linker itself |
| #define FLAG_NEW_SOINFO 0x40000000 // new soinfo format |
| |
| #define SOINFO_NAME_LEN 128 |
| |
| typedef void (*linker_function_t)(); |
| |
| // Android uses RELA for aarch64 and x86_64. mips64 still uses REL. |
| #if defined(__aarch64__) || defined(__x86_64__) |
| #define USE_RELA 1 |
| #endif |
| |
| struct soinfo; |
| |
| class SoinfoListAllocator { |
| public: |
| static LinkedListEntry<soinfo>* alloc(); |
| static void free(LinkedListEntry<soinfo>* entry); |
| private: |
| // unconstructable |
| DISALLOW_IMPLICIT_CONSTRUCTORS(SoinfoListAllocator); |
| }; |
| |
| struct soinfo { |
| public: |
| typedef LinkedList<soinfo, SoinfoListAllocator> soinfo_list_t; |
| public: |
| char name[SOINFO_NAME_LEN]; |
| const ElfW(Phdr)* phdr; |
| size_t phnum; |
| ElfW(Addr) entry; |
| ElfW(Addr) base; |
| // ARC MOD BEGIN |
| // There are no code change, but the meaning of this field has |
| // changed. In the original Bionic, this field contains the total |
| // size loaded segments and it assumes there are no gaps between |
| // each segment. For NaCl, we use this field as the size of the |
| // text segment. NaCl binary has a big gap between the text |
| // segment and the data segments so if we use the original value, |
| // find_containing_library will not return the correct library. |
| // ARC MOD END |
| size_t size; |
| |
| #ifndef __LP64__ |
| uint32_t unused1; // DO NOT USE, maintained for compatibility. |
| #endif |
| |
| ElfW(Dyn)* dynamic; |
| |
| #ifndef __LP64__ |
| uint32_t unused2; // DO NOT USE, maintained for compatibility |
| uint32_t unused3; // DO NOT USE, maintained for compatibility |
| #endif |
| |
| soinfo* next; |
| unsigned flags; |
| |
| const char* strtab; |
| ElfW(Sym)* symtab; |
| |
| size_t nbucket; |
| size_t nchain; |
| unsigned* bucket; |
| unsigned* chain; |
| |
| #if defined(__mips__) || !defined(__LP64__) |
| // This is only used by mips and mips64, but needs to be here for |
| // all 32-bit architectures to preserve binary compatibility. |
| ElfW(Addr)** plt_got; |
| #endif |
| |
| #if defined(USE_RELA) |
| ElfW(Rela)* plt_rela; |
| size_t plt_rela_count; |
| |
| ElfW(Rela)* rela; |
| size_t rela_count; |
| #else |
| ElfW(Rel)* plt_rel; |
| size_t plt_rel_count; |
| |
| ElfW(Rel)* rel; |
| size_t rel_count; |
| #endif |
| |
| linker_function_t* preinit_array; |
| size_t preinit_array_count; |
| |
| linker_function_t* init_array; |
| size_t init_array_count; |
| linker_function_t* fini_array; |
| size_t fini_array_count; |
| |
| // ARC MOD BEGIN |
| // We pass __nacl_irt_query from the loader to libc.so linked |
| // against the main executable. In nacl-glibc, the loader passes |
| // __nacl_irt_query using AT_SYSINFO when the loader calls _start |
| // in the main executable. However, we cannot do this for Bionic |
| // because the loader of Bionic calls initializer functions in |
| // .ctors section before it calls _start. |
| #if defined(HAVE_ARC) |
| void (*init_func)(__nacl_irt_query_fn_t irt_query); |
| #else |
| // ARC MOD END |
| linker_function_t init_func; |
| // ARC MOD BEGIN |
| #endif |
| // ARC MOD END |
| linker_function_t fini_func; |
| |
| #if defined(__arm__) |
| // ARM EABI section used for stack unwinding. |
| unsigned* ARM_exidx; |
| size_t ARM_exidx_count; |
| #elif defined(__mips__) |
| unsigned mips_symtabno; |
| unsigned mips_local_gotno; |
| unsigned mips_gotsym; |
| #endif |
| |
| size_t ref_count; |
| link_map link_map_head; |
| |
| bool constructors_called; |
| |
| // When you read a virtual address from the ELF file, add this |
| // value to get the corresponding address in the process' address space. |
| ElfW(Addr) load_bias; |
| |
| #if !defined(__LP64__) |
| bool has_text_relocations; |
| #endif |
| bool has_DT_SYMBOLIC; |
| // ARC MOD BEGIN |
| // A flag to distinguish NDK libraries. |
| bool is_ndk; |
| // ARC MOD END |
| void CallConstructors(); |
| void CallDestructors(); |
| void CallPreInitConstructors(); |
| |
| void add_child(soinfo* child); |
| void remove_all_links(); |
| |
| void set_st_dev(dev_t st_dev); |
| void set_st_ino(ino_t st_ino); |
| ino_t get_st_ino(); |
| dev_t get_st_dev(); |
| |
| soinfo_list_t& get_children(); |
| |
| private: |
| void CallArray(const char* array_name, linker_function_t* functions, size_t count, bool reverse); |
| void CallFunction(const char* function_name, linker_function_t function); |
| |
| private: |
| // This part of the structure is only available |
| // when FLAG_NEW_SOINFO is set in this->flags. |
| unsigned int version; |
| |
| dev_t st_dev; |
| ino_t st_ino; |
| |
| // dependency graph |
| soinfo_list_t children; |
| soinfo_list_t parents; |
| |
| }; |
| |
| extern soinfo* get_libdl_info(); |
| |
| void do_android_get_LD_LIBRARY_PATH(char*, size_t); |
| void do_android_update_LD_LIBRARY_PATH(const char* ld_library_path); |
| soinfo* do_dlopen(const char* name, int flags, const android_dlextinfo* extinfo); |
| void do_dlclose(soinfo* si); |
| |
| ElfW(Sym)* dlsym_linear_lookup(const char* name, soinfo** found, soinfo* start); |
| soinfo* find_containing_library(const void* addr); |
| |
| ElfW(Sym)* dladdr_find_symbol(soinfo* si, const void* addr); |
| ElfW(Sym)* dlsym_handle_lookup(soinfo* si, soinfo** found, const char* name); |
| |
| void debuggerd_init(); |
| extern "C" abort_msg_t* g_abort_message; |
| extern "C" void notify_gdb_of_libraries(); |
| |
| char* linker_get_error_buffer(); |
| size_t linker_get_error_buffer_size(); |
| |
| #endif |