/* Plugin support for BFD. Copyright (C) 2009-2021 Free Software Foundation, Inc. This file is part of BFD, the Binary File Descriptor library. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */ #include "sysdep.h" #include "bfd.h" #if BFD_SUPPORTS_PLUGINS #include #ifdef HAVE_DLFCN_H #include #elif defined (HAVE_WINDOWS_H) #include #else #error Unknown how to handle dynamic-load-libraries. #endif #include #include "plugin-api.h" #include "plugin.h" #include "libbfd.h" #include "libiberty.h" #include #if !defined (HAVE_DLFCN_H) && defined (HAVE_WINDOWS_H) #define RTLD_NOW 0 /* Dummy value. */ static void * dlopen (const char *file, int mode ATTRIBUTE_UNUSED) { return LoadLibrary (file); } static void * dlsym (void *handle, const char *name) { return GetProcAddress (handle, name); } static int ATTRIBUTE_UNUSED dlclose (void *handle) { FreeLibrary (handle); return 0; } static const char * dlerror (void) { return "Unable to load DLL."; } #endif /* !defined (HAVE_DLFCN_H) && defined (HAVE_WINDOWS_H) */ #define bfd_plugin_close_and_cleanup _bfd_generic_close_and_cleanup #define bfd_plugin_bfd_free_cached_info _bfd_generic_bfd_free_cached_info #define bfd_plugin_new_section_hook _bfd_generic_new_section_hook #define bfd_plugin_get_section_contents _bfd_generic_get_section_contents #define bfd_plugin_get_section_contents_in_window _bfd_generic_get_section_contents_in_window #define bfd_plugin_bfd_copy_private_header_data _bfd_generic_bfd_copy_private_header_data #define bfd_plugin_bfd_merge_private_bfd_data _bfd_generic_bfd_merge_private_bfd_data #define bfd_plugin_bfd_copy_private_header_data _bfd_generic_bfd_copy_private_header_data #define bfd_plugin_bfd_set_private_flags _bfd_generic_bfd_set_private_flags #define bfd_plugin_core_file_matches_executable_p generic_core_file_matches_executable_p #define bfd_plugin_bfd_is_local_label_name _bfd_nosymbols_bfd_is_local_label_name #define bfd_plugin_bfd_is_target_special_symbol _bfd_bool_bfd_asymbol_false #define bfd_plugin_get_lineno _bfd_nosymbols_get_lineno #define bfd_plugin_find_nearest_line _bfd_nosymbols_find_nearest_line #define bfd_plugin_find_line _bfd_nosymbols_find_line #define bfd_plugin_find_inliner_info _bfd_nosymbols_find_inliner_info #define bfd_plugin_get_symbol_version_string _bfd_nosymbols_get_symbol_version_string #define bfd_plugin_bfd_make_debug_symbol _bfd_nosymbols_bfd_make_debug_symbol #define bfd_plugin_read_minisymbols _bfd_generic_read_minisymbols #define bfd_plugin_minisymbol_to_symbol _bfd_generic_minisymbol_to_symbol #define bfd_plugin_set_arch_mach bfd_default_set_arch_mach #define bfd_plugin_set_section_contents _bfd_generic_set_section_contents #define bfd_plugin_bfd_get_relocated_section_contents bfd_generic_get_relocated_section_contents #define bfd_plugin_bfd_relax_section bfd_generic_relax_section #define bfd_plugin_bfd_link_hash_table_create _bfd_generic_link_hash_table_create #define bfd_plugin_bfd_link_add_symbols _bfd_generic_link_add_symbols #define bfd_plugin_bfd_link_just_syms _bfd_generic_link_just_syms #define bfd_plugin_bfd_final_link _bfd_generic_final_link #define bfd_plugin_bfd_link_split_section _bfd_generic_link_split_section #define bfd_plugin_bfd_gc_sections bfd_generic_gc_sections #define bfd_plugin_bfd_lookup_section_flags bfd_generic_lookup_section_flags #define bfd_plugin_bfd_merge_sections bfd_generic_merge_sections #define bfd_plugin_bfd_is_group_section bfd_generic_is_group_section #define bfd_plugin_bfd_group_name bfd_generic_group_name #define bfd_plugin_bfd_discard_group bfd_generic_discard_group #define bfd_plugin_section_already_linked _bfd_generic_section_already_linked #define bfd_plugin_bfd_define_common_symbol bfd_generic_define_common_symbol #define bfd_plugin_bfd_link_hide_symbol _bfd_generic_link_hide_symbol #define bfd_plugin_bfd_define_start_stop bfd_generic_define_start_stop #define bfd_plugin_bfd_copy_link_hash_symbol_type _bfd_generic_copy_link_hash_symbol_type #define bfd_plugin_bfd_link_check_relocs _bfd_generic_link_check_relocs static enum ld_plugin_status message (int level ATTRIBUTE_UNUSED, const char * format, ...) { va_list args; va_start (args, format); printf ("bfd plugin: "); vprintf (format, args); putchar ('\n'); va_end (args); return LDPS_OK; } struct plugin_list_entry { /* These must be initialized for each IR object with LTO wrapper. */ ld_plugin_claim_file_handler claim_file; ld_plugin_all_symbols_read_handler all_symbols_read; ld_plugin_all_symbols_read_handler cleanup_handler; bool has_symbol_type; struct plugin_list_entry *next; /* These can be reused for all IR objects. */ const char *plugin_name; }; static const char *plugin_program_name; void bfd_plugin_set_program_name (const char *program_name) { plugin_program_name = program_name; } static struct plugin_list_entry *plugin_list = NULL; static struct plugin_list_entry *current_plugin = NULL; /* Register a claim-file handler. */ static enum ld_plugin_status register_claim_file (ld_plugin_claim_file_handler handler) { current_plugin->claim_file = handler; return LDPS_OK; } static enum ld_plugin_status add_symbols (void * handle, int nsyms, const struct ld_plugin_symbol * syms) { bfd *abfd = handle; struct plugin_data_struct *plugin_data = bfd_alloc (abfd, sizeof (plugin_data_struct)); if (!plugin_data) return LDPS_ERR; plugin_data->nsyms = nsyms; plugin_data->syms = syms; if (nsyms != 0) abfd->flags |= HAS_SYMS; abfd->tdata.plugin_data = plugin_data; return LDPS_OK; } static enum ld_plugin_status add_symbols_v2 (void *handle, int nsyms, const struct ld_plugin_symbol *syms) { current_plugin->has_symbol_type = true; return add_symbols (handle, nsyms, syms); } int bfd_plugin_open_input (bfd *ibfd, struct ld_plugin_input_file *file) { bfd *iobfd; iobfd = ibfd; while (iobfd->my_archive && !bfd_is_thin_archive (iobfd->my_archive)) iobfd = iobfd->my_archive; file->name = bfd_get_filename (iobfd); if (!iobfd->iostream && !bfd_open_file (iobfd)) return 0; /* The plugin API expects that the file descriptor won't be closed and reused as done by the bfd file cache. So open it again. dup isn't good enough. plugin IO uses lseek/read while BFD uses fseek/fread. It isn't wise to mix the unistd and stdio calls on the same underlying file descriptor. */ file->fd = open (file->name, O_RDONLY | O_BINARY); if (file->fd < 0) return 0; if (iobfd == ibfd) { struct stat stat_buf; if (fstat (file->fd, &stat_buf)) { close(file->fd); return 0; } file->offset = 0; file->filesize = stat_buf.st_size; } else { file->offset = ibfd->origin; file->filesize = arelt_size (ibfd); } return 1; } static int try_claim (bfd *abfd) { int claimed = 0; struct ld_plugin_input_file file; file.handle = abfd; if (bfd_plugin_open_input (abfd, &file) && current_plugin->claim_file) { current_plugin->claim_file (&file, &claimed); close (file.fd); } return claimed; } static bool try_load_plugin (const char *pname, struct plugin_list_entry *plugin_list_iter, bfd *abfd, bool build_list_p) { void *plugin_handle; struct ld_plugin_tv tv[5]; int i; ld_plugin_onload onload; enum ld_plugin_status status; bool result = false; /* NB: Each object is independent. Reuse the previous plugin from the last run will lead to wrong result. */ if (current_plugin) memset (current_plugin, 0, offsetof (struct plugin_list_entry, next)); if (plugin_list_iter) pname = plugin_list_iter->plugin_name; plugin_handle = dlopen (pname, RTLD_NOW); if (!plugin_handle) { /* If we are building a list of viable plugins, then we do not bother the user with the details of any plugins that cannot be loaded. */ if (! build_list_p) _bfd_error_handler ("Failed to load plugin '%s', reason: %s\n", pname, dlerror ()); return false; } if (plugin_list_iter == NULL) { size_t length_plugin_name = strlen (pname) + 1; char *plugin_name = bfd_malloc (length_plugin_name); if (plugin_name == NULL) goto short_circuit; plugin_list_iter = bfd_malloc (sizeof *plugin_list_iter); if (plugin_list_iter == NULL) { free (plugin_name); goto short_circuit; } /* Make a copy of PNAME since PNAME from load_plugin () will be freed. */ memcpy (plugin_name, pname, length_plugin_name); memset (plugin_list_iter, 0, sizeof (*plugin_list_iter)); plugin_list_iter->plugin_name = plugin_name; plugin_list_iter->next = plugin_list; plugin_list = plugin_list_iter; } current_plugin = plugin_list_iter; if (build_list_p) goto short_circuit; onload = dlsym (plugin_handle, "onload"); if (!onload) goto short_circuit; i = 0; tv[i].tv_tag = LDPT_MESSAGE; tv[i].tv_u.tv_message = message; ++i; tv[i].tv_tag = LDPT_REGISTER_CLAIM_FILE_HOOK; tv[i].tv_u.tv_register_claim_file = register_claim_file; ++i; tv[i].tv_tag = LDPT_ADD_SYMBOLS; tv[i].tv_u.tv_add_symbols = add_symbols; ++i; tv[i].tv_tag = LDPT_ADD_SYMBOLS_V2; tv[i].tv_u.tv_add_symbols = add_symbols_v2; ++i; tv[i].tv_tag = LDPT_NULL; tv[i].tv_u.tv_val = 0; /* LTO plugin will call handler hooks to set up plugin handlers. */ status = (*onload)(tv); if (status != LDPS_OK) goto short_circuit; abfd->plugin_format = bfd_plugin_no; if (!current_plugin->claim_file) goto short_circuit; if (!try_claim (abfd)) goto short_circuit; abfd->plugin_format = bfd_plugin_yes; result = true; short_circuit: dlclose (plugin_handle); return result; } /* There may be plugin libraries in lib/bfd-plugins. */ static int has_plugin_list = -1; static bfd_cleanup (*ld_plugin_object_p) (bfd *); static const char *plugin_name; void bfd_plugin_set_plugin (const char *p) { plugin_name = p; } /* Return TRUE if a plugin library is used. */ bool bfd_plugin_specified_p (void) { return plugin_list != NULL; } /* Return TRUE if ABFD can be claimed by linker LTO plugin. */ bool bfd_link_plugin_object_p (bfd *abfd) { if (ld_plugin_object_p) return ld_plugin_object_p (abfd) != NULL; return false; } extern const bfd_target plugin_vec; /* Return TRUE if TARGET is a pointer to plugin_vec. */ bool bfd_plugin_target_p (const bfd_target *target) { return target == &plugin_vec; } /* Register OBJECT_P to be used by bfd_plugin_object_p. */ void register_ld_plugin_object_p (bfd_cleanup (*object_p) (bfd *)) { ld_plugin_object_p = object_p; } static void build_plugin_list (bfd *abfd) { /* The intent was to search ${libdir}/bfd-plugins for plugins, but unfortunately the original implementation wasn't precisely that when configuring binutils using --libdir. Search in the proper path first, then the old one for backwards compatibility. */ static const char *path[] = { LIBDIR "/bfd-plugins", BINDIR "/../lib/bfd-plugins" }; struct stat last_st; unsigned int i; if (has_plugin_list >= 0) return; /* Try not to search the same dir twice, by looking at st_dev and st_ino for the dir. If we are on a file system that always sets st_ino to zero or the actual st_ino is zero we might waste some time, but that doesn't matter too much. */ last_st.st_dev = 0; last_st.st_ino = 0; for (i = 0; i < sizeof (path) / sizeof (path[0]); i++) { char *plugin_dir = make_relative_prefix (plugin_program_name, BINDIR, path[i]); if (plugin_dir) { struct stat st; DIR *d; if (stat (plugin_dir, &st) == 0 && S_ISDIR (st.st_mode) && !(last_st.st_dev == st.st_dev && last_st.st_ino == st.st_ino && st.st_ino != 0) && (d = opendir (plugin_dir)) != NULL) { struct dirent *ent; last_st.st_dev = st.st_dev; last_st.st_ino = st.st_ino; while ((ent = readdir (d)) != NULL) { char *full_name; full_name = concat (plugin_dir, "/", ent->d_name, NULL); if (stat (full_name, &st) == 0 && S_ISREG (st.st_mode)) (void) try_load_plugin (full_name, NULL, abfd, true); free (full_name); } closedir (d); } free (plugin_dir); } } has_plugin_list = plugin_list != NULL; } static bool load_plugin (bfd *abfd) { struct plugin_list_entry *plugin_list_iter; if (plugin_name) return try_load_plugin (plugin_name, plugin_list, abfd, false); if (plugin_program_name == NULL) return false; build_plugin_list (abfd); for (plugin_list_iter = plugin_list; plugin_list_iter; plugin_list_iter = plugin_list_iter->next) if (try_load_plugin (NULL, plugin_list_iter, abfd, false)) return true; return false; } static bfd_cleanup bfd_plugin_object_p (bfd *abfd) { if (ld_plugin_object_p) return ld_plugin_object_p (abfd); if (abfd->plugin_format == bfd_plugin_unknown && !load_plugin (abfd)) return NULL; return abfd->plugin_format == bfd_plugin_yes ? _bfd_no_cleanup : NULL; } /* Copy any private info we understand from the input bfd to the output bfd. */ static bool bfd_plugin_bfd_copy_private_bfd_data (bfd *ibfd ATTRIBUTE_UNUSED, bfd *obfd ATTRIBUTE_UNUSED) { BFD_ASSERT (0); return true; } /* Copy any private info we understand from the input section to the output section. */ static bool bfd_plugin_bfd_copy_private_section_data (bfd *ibfd ATTRIBUTE_UNUSED, asection *isection ATTRIBUTE_UNUSED, bfd *obfd ATTRIBUTE_UNUSED, asection *osection ATTRIBUTE_UNUSED) { BFD_ASSERT (0); return true; } /* Copy any private info we understand from the input symbol to the output symbol. */ static bool bfd_plugin_bfd_copy_private_symbol_data (bfd *ibfd ATTRIBUTE_UNUSED, asymbol *isymbol ATTRIBUTE_UNUSED, bfd *obfd ATTRIBUTE_UNUSED, asymbol *osymbol ATTRIBUTE_UNUSED) { BFD_ASSERT (0); return true; } static bool bfd_plugin_bfd_print_private_bfd_data (bfd *abfd ATTRIBUTE_UNUSED, PTR ptr ATTRIBUTE_UNUSED) { BFD_ASSERT (0); return true; } static char * bfd_plugin_core_file_failing_command (bfd *abfd ATTRIBUTE_UNUSED) { BFD_ASSERT (0); return NULL; } static int bfd_plugin_core_file_failing_signal (bfd *abfd ATTRIBUTE_UNUSED) { BFD_ASSERT (0); return 0; } static int bfd_plugin_core_file_pid (bfd *abfd ATTRIBUTE_UNUSED) { BFD_ASSERT (0); return 0; } static long bfd_plugin_get_symtab_upper_bound (bfd *abfd) { struct plugin_data_struct *plugin_data = abfd->tdata.plugin_data; long nsyms = plugin_data->nsyms; BFD_ASSERT (nsyms >= 0); return ((nsyms + 1) * sizeof (asymbol *)); } static flagword convert_flags (const struct ld_plugin_symbol *sym) { switch (sym->def) { case LDPK_DEF: case LDPK_COMMON: case LDPK_UNDEF: return BSF_GLOBAL; case LDPK_WEAKUNDEF: case LDPK_WEAKDEF: return BSF_GLOBAL | BSF_WEAK; default: BFD_ASSERT (0); return 0; } } static long bfd_plugin_canonicalize_symtab (bfd *abfd, asymbol **alocation) { struct plugin_data_struct *plugin_data = abfd->tdata.plugin_data; long nsyms = plugin_data->nsyms; const struct ld_plugin_symbol *syms = plugin_data->syms; static asection fake_text_section = BFD_FAKE_SECTION (fake_text_section, NULL, "plug", 0, SEC_ALLOC | SEC_LOAD | SEC_CODE | SEC_HAS_CONTENTS); static asection fake_data_section = BFD_FAKE_SECTION (fake_data_section, NULL, "plug", 0, SEC_ALLOC | SEC_LOAD | SEC_DATA | SEC_HAS_CONTENTS); static asection fake_bss_section = BFD_FAKE_SECTION (fake_bss_section, NULL, "plug", 0, SEC_ALLOC); static asection fake_common_section = BFD_FAKE_SECTION (fake_common_section, NULL, "plug", 0, SEC_IS_COMMON); int i; for (i = 0; i < nsyms; i++) { asymbol *s = bfd_alloc (abfd, sizeof (asymbol)); BFD_ASSERT (s); alocation[i] = s; s->the_bfd = abfd; s->name = syms[i].name; s->value = 0; s->flags = convert_flags (&syms[i]); switch (syms[i].def) { case LDPK_COMMON: s->section = &fake_common_section; break; case LDPK_UNDEF: case LDPK_WEAKUNDEF: s->section = bfd_und_section_ptr; break; case LDPK_DEF: case LDPK_WEAKDEF: if (current_plugin->has_symbol_type) switch (syms[i].symbol_type) { default: /* FIXME: Should we issue an error here ? */ case LDST_UNKNOWN: /* What is the best fake section for LDST_UNKNOWN? */ case LDST_FUNCTION: s->section = &fake_text_section; break; case LDST_VARIABLE: if (syms[i].section_kind == LDSSK_BSS) s->section = &fake_bss_section; else s->section = &fake_data_section; break; } else s->section = &fake_text_section; break; default: BFD_ASSERT (0); } s->udata.p = (void *) &syms[i]; } return nsyms; } static void bfd_plugin_print_symbol (bfd *abfd ATTRIBUTE_UNUSED, PTR afile ATTRIBUTE_UNUSED, asymbol *symbol ATTRIBUTE_UNUSED, bfd_print_symbol_type how ATTRIBUTE_UNUSED) { BFD_ASSERT (0); } static void bfd_plugin_get_symbol_info (bfd *abfd ATTRIBUTE_UNUSED, asymbol *symbol, symbol_info *ret) { bfd_symbol_info (symbol, ret); } /* Make an empty symbol. */ static asymbol * bfd_plugin_make_empty_symbol (bfd *abfd) { asymbol *new_symbol = bfd_zalloc (abfd, sizeof (asymbol)); if (new_symbol == NULL) return new_symbol; new_symbol->the_bfd = abfd; return new_symbol; } static int bfd_plugin_sizeof_headers (bfd *a ATTRIBUTE_UNUSED, struct bfd_link_info *info ATTRIBUTE_UNUSED) { BFD_ASSERT (0); return 0; } const bfd_target plugin_vec = { "plugin", /* Name. */ bfd_target_unknown_flavour, BFD_ENDIAN_LITTLE, /* Target byte order. */ BFD_ENDIAN_LITTLE, /* Target headers byte order. */ (HAS_RELOC | EXEC_P | /* Object flags. */ HAS_LINENO | HAS_DEBUG | HAS_SYMS | HAS_LOCALS | DYNAMIC | WP_TEXT | D_PAGED), (SEC_CODE | SEC_DATA | SEC_ROM | SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC), /* Section flags. */ 0, /* symbol_leading_char. */ '/', /* ar_pad_char. */ 15, /* ar_max_namelen. */ 255, /* match priority. */ TARGET_KEEP_UNUSED_SECTION_SYMBOLS, /* keep unused section symbols. */ bfd_getl64, bfd_getl_signed_64, bfd_putl64, bfd_getl32, bfd_getl_signed_32, bfd_putl32, bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* data */ bfd_getl64, bfd_getl_signed_64, bfd_putl64, bfd_getl32, bfd_getl_signed_32, bfd_putl32, bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* hdrs */ { /* bfd_check_format. */ _bfd_dummy_target, bfd_plugin_object_p, bfd_generic_archive_p, _bfd_dummy_target }, { /* bfd_set_format. */ _bfd_bool_bfd_false_error, _bfd_bool_bfd_false_error, _bfd_generic_mkarchive, _bfd_bool_bfd_false_error, }, { /* bfd_write_contents. */ _bfd_bool_bfd_false_error, _bfd_bool_bfd_false_error, _bfd_write_archive_contents, _bfd_bool_bfd_false_error, }, BFD_JUMP_TABLE_GENERIC (bfd_plugin), BFD_JUMP_TABLE_COPY (bfd_plugin), BFD_JUMP_TABLE_CORE (bfd_plugin), #ifdef USE_64_BIT_ARCHIVE BFD_JUMP_TABLE_ARCHIVE (_bfd_archive_64_bit), #else BFD_JUMP_TABLE_ARCHIVE (_bfd_archive_coff), #endif BFD_JUMP_TABLE_SYMBOLS (bfd_plugin), BFD_JUMP_TABLE_RELOCS (_bfd_norelocs), BFD_JUMP_TABLE_WRITE (bfd_plugin), BFD_JUMP_TABLE_LINK (bfd_plugin), BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic), NULL, NULL /* backend_data. */ }; #endif /* BFD_SUPPORTS_PLUGINS */