1 /* Plugin support for BFD. 2 Copyright (C) 2009-2016 Free Software Foundation, Inc. 3 4 This file is part of BFD, the Binary File Descriptor library. 5 6 This program is free software; you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by 8 the Free Software Foundation; either version 3 of the License, or 9 (at your option) any later version. 10 11 This program is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 GNU General Public License for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with this program; if not, write to the Free Software 18 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, 19 MA 02110-1301, USA. */ 20 21 #include "sysdep.h" 22 #include "bfd.h" 23 24 #if BFD_SUPPORTS_PLUGINS 25 26 #include <assert.h> 27 #ifdef HAVE_DLFCN_H 28 #include <dlfcn.h> 29 #elif defined (HAVE_WINDOWS_H) 30 #include <windows.h> 31 #else 32 #error Unknown how to handle dynamic-load-libraries. 33 #endif 34 #include <stdarg.h> 35 #include "plugin-api.h" 36 #include "plugin.h" 37 #include "libbfd.h" 38 #include "libiberty.h" 39 #include <dirent.h> 40 41 #if !defined (HAVE_DLFCN_H) && defined (HAVE_WINDOWS_H) 42 43 #define RTLD_NOW 0 /* Dummy value. */ 44 45 static void * 46 dlopen (const char *file, int mode ATTRIBUTE_UNUSED) 47 { 48 return LoadLibrary (file); 49 } 50 51 static void * 52 dlsym (void *handle, const char *name) 53 { 54 return GetProcAddress (handle, name); 55 } 56 57 static int ATTRIBUTE_UNUSED 58 dlclose (void *handle) 59 { 60 FreeLibrary (handle); 61 return 0; 62 } 63 64 static const char * 65 dlerror (void) 66 { 67 return "Unable to load DLL."; 68 } 69 70 #endif /* !defined (HAVE_DLFCN_H) && defined (HAVE_WINDOWS_H) */ 71 72 #define bfd_plugin_close_and_cleanup _bfd_generic_close_and_cleanup 73 #define bfd_plugin_bfd_free_cached_info _bfd_generic_bfd_free_cached_info 74 #define bfd_plugin_new_section_hook _bfd_generic_new_section_hook 75 #define bfd_plugin_get_section_contents _bfd_generic_get_section_contents 76 #define bfd_plugin_get_section_contents_in_window _bfd_generic_get_section_contents_in_window 77 #define bfd_plugin_bfd_copy_private_header_data _bfd_generic_bfd_copy_private_header_data 78 #define bfd_plugin_bfd_merge_private_bfd_data _bfd_generic_bfd_merge_private_bfd_data 79 #define bfd_plugin_bfd_copy_private_header_data _bfd_generic_bfd_copy_private_header_data 80 #define bfd_plugin_bfd_set_private_flags _bfd_generic_bfd_set_private_flags 81 #define bfd_plugin_core_file_matches_executable_p generic_core_file_matches_executable_p 82 #define bfd_plugin_bfd_is_local_label_name _bfd_nosymbols_bfd_is_local_label_name 83 #define bfd_plugin_bfd_is_target_special_symbol ((bfd_boolean (*) (bfd *, asymbol *)) bfd_false) 84 #define bfd_plugin_get_lineno _bfd_nosymbols_get_lineno 85 #define bfd_plugin_find_nearest_line _bfd_nosymbols_find_nearest_line 86 #define bfd_plugin_find_line _bfd_nosymbols_find_line 87 #define bfd_plugin_find_inliner_info _bfd_nosymbols_find_inliner_info 88 #define bfd_plugin_get_symbol_version_string _bfd_nosymbols_get_symbol_version_string 89 #define bfd_plugin_bfd_make_debug_symbol _bfd_nosymbols_bfd_make_debug_symbol 90 #define bfd_plugin_read_minisymbols _bfd_generic_read_minisymbols 91 #define bfd_plugin_minisymbol_to_symbol _bfd_generic_minisymbol_to_symbol 92 #define bfd_plugin_set_arch_mach bfd_default_set_arch_mach 93 #define bfd_plugin_set_section_contents _bfd_generic_set_section_contents 94 #define bfd_plugin_bfd_get_relocated_section_contents bfd_generic_get_relocated_section_contents 95 #define bfd_plugin_bfd_relax_section bfd_generic_relax_section 96 #define bfd_plugin_bfd_link_hash_table_create _bfd_generic_link_hash_table_create 97 #define bfd_plugin_bfd_link_add_symbols _bfd_generic_link_add_symbols 98 #define bfd_plugin_bfd_link_just_syms _bfd_generic_link_just_syms 99 #define bfd_plugin_bfd_final_link _bfd_generic_final_link 100 #define bfd_plugin_bfd_link_split_section _bfd_generic_link_split_section 101 #define bfd_plugin_bfd_gc_sections bfd_generic_gc_sections 102 #define bfd_plugin_bfd_lookup_section_flags bfd_generic_lookup_section_flags 103 #define bfd_plugin_bfd_merge_sections bfd_generic_merge_sections 104 #define bfd_plugin_bfd_is_group_section bfd_generic_is_group_section 105 #define bfd_plugin_bfd_discard_group bfd_generic_discard_group 106 #define bfd_plugin_section_already_linked _bfd_generic_section_already_linked 107 #define bfd_plugin_bfd_define_common_symbol bfd_generic_define_common_symbol 108 #define bfd_plugin_bfd_copy_link_hash_symbol_type _bfd_generic_copy_link_hash_symbol_type 109 #define bfd_plugin_bfd_link_check_relocs _bfd_generic_link_check_relocs 110 111 static enum ld_plugin_status 112 message (int level ATTRIBUTE_UNUSED, 113 const char * format, ...) 114 { 115 va_list args; 116 va_start (args, format); 117 printf ("bfd plugin: "); 118 vprintf (format, args); 119 putchar ('\n'); 120 va_end (args); 121 return LDPS_OK; 122 } 123 124 /* Register a claim-file handler. */ 125 static ld_plugin_claim_file_handler claim_file; 126 127 static enum ld_plugin_status 128 register_claim_file (ld_plugin_claim_file_handler handler) 129 { 130 claim_file = handler; 131 return LDPS_OK; 132 } 133 134 static enum ld_plugin_status 135 add_symbols (void * handle, 136 int nsyms, 137 const struct ld_plugin_symbol * syms) 138 { 139 bfd *abfd = handle; 140 struct plugin_data_struct *plugin_data = 141 bfd_alloc (abfd, sizeof (plugin_data_struct)); 142 143 plugin_data->nsyms = nsyms; 144 plugin_data->syms = syms; 145 146 if (nsyms != 0) 147 abfd->flags |= HAS_SYMS; 148 149 abfd->tdata.plugin_data = plugin_data; 150 return LDPS_OK; 151 } 152 153 static const char *plugin_program_name; 154 155 void 156 bfd_plugin_set_program_name (const char *program_name) 157 { 158 plugin_program_name = program_name; 159 } 160 161 int 162 bfd_plugin_open_input (bfd *ibfd, struct ld_plugin_input_file *file) 163 { 164 bfd *iobfd; 165 166 iobfd = ibfd; 167 if (ibfd->my_archive && !bfd_is_thin_archive (ibfd->my_archive)) 168 iobfd = ibfd->my_archive; 169 file->name = iobfd->filename; 170 171 if (!iobfd->iostream && !bfd_open_file (iobfd)) 172 return 0; 173 174 file->fd = fileno ((FILE *) iobfd->iostream); 175 176 if (iobfd == ibfd) 177 { 178 struct stat stat_buf; 179 if (fstat (file->fd, &stat_buf)) 180 return 0; 181 file->offset = 0; 182 file->filesize = stat_buf.st_size; 183 } 184 else 185 { 186 file->offset = ibfd->origin; 187 file->filesize = arelt_size (ibfd); 188 } 189 return 1; 190 } 191 192 static int 193 try_claim (bfd *abfd) 194 { 195 int claimed = 0; 196 struct ld_plugin_input_file file; 197 198 if (!bfd_plugin_open_input (abfd, &file)) 199 return 0; 200 file.handle = abfd; 201 off_t cur_offset = lseek (file.fd, 0, SEEK_CUR); 202 claim_file (&file, &claimed); 203 lseek (file.fd, cur_offset, SEEK_SET); 204 return claimed; 205 } 206 207 static int 208 try_load_plugin (const char *pname, bfd *abfd, int *has_plugin_p) 209 { 210 void *plugin_handle; 211 struct ld_plugin_tv tv[4]; 212 int i; 213 ld_plugin_onload onload; 214 enum ld_plugin_status status; 215 216 *has_plugin_p = 0; 217 218 plugin_handle = dlopen (pname, RTLD_NOW); 219 if (!plugin_handle) 220 { 221 (*_bfd_error_handler)("%s\n", dlerror ()); 222 return 0; 223 } 224 225 onload = dlsym (plugin_handle, "onload"); 226 if (!onload) 227 goto err; 228 229 i = 0; 230 tv[i].tv_tag = LDPT_MESSAGE; 231 tv[i].tv_u.tv_message = message; 232 233 ++i; 234 tv[i].tv_tag = LDPT_REGISTER_CLAIM_FILE_HOOK; 235 tv[i].tv_u.tv_register_claim_file = register_claim_file; 236 237 ++i; 238 tv[i].tv_tag = LDPT_ADD_SYMBOLS; 239 tv[i].tv_u.tv_add_symbols = add_symbols; 240 241 ++i; 242 tv[i].tv_tag = LDPT_NULL; 243 tv[i].tv_u.tv_val = 0; 244 245 status = (*onload)(tv); 246 247 if (status != LDPS_OK) 248 goto err; 249 250 *has_plugin_p = 1; 251 252 abfd->plugin_format = bfd_plugin_no; 253 254 if (!claim_file) 255 goto err; 256 257 if (!try_claim (abfd)) 258 goto err; 259 260 abfd->plugin_format = bfd_plugin_yes; 261 262 return 1; 263 264 err: 265 return 0; 266 } 267 268 /* There may be plugin libraries in lib/bfd-plugins. */ 269 270 static int has_plugin = -1; 271 272 static const bfd_target *(*ld_plugin_object_p) (bfd *); 273 274 static const char *plugin_name; 275 276 void 277 bfd_plugin_set_plugin (const char *p) 278 { 279 plugin_name = p; 280 has_plugin = p != NULL; 281 } 282 283 /* Return TRUE if a plugin library is used. */ 284 285 bfd_boolean 286 bfd_plugin_specified_p (void) 287 { 288 return has_plugin > 0; 289 } 290 291 /* Return TRUE if ABFD can be claimed by linker LTO plugin. */ 292 293 bfd_boolean 294 bfd_link_plugin_object_p (bfd *abfd) 295 { 296 if (ld_plugin_object_p) 297 return ld_plugin_object_p (abfd) != NULL; 298 return FALSE; 299 } 300 301 extern const bfd_target plugin_vec; 302 303 /* Return TRUE if TARGET is a pointer to plugin_vec. */ 304 305 bfd_boolean 306 bfd_plugin_target_p (const bfd_target *target) 307 { 308 return target == &plugin_vec; 309 } 310 311 /* Register OBJECT_P to be used by bfd_plugin_object_p. */ 312 313 void 314 register_ld_plugin_object_p (const bfd_target *(*object_p) (bfd *)) 315 { 316 ld_plugin_object_p = object_p; 317 } 318 319 static int 320 load_plugin (bfd *abfd) 321 { 322 char *plugin_dir; 323 char *p; 324 DIR *d; 325 struct dirent *ent; 326 int found = 0; 327 328 if (!has_plugin) 329 return found; 330 331 if (plugin_name) 332 return try_load_plugin (plugin_name, abfd, &has_plugin); 333 334 if (plugin_program_name == NULL) 335 return found; 336 337 plugin_dir = concat (BINDIR, "/../lib/bfd-plugins", NULL); 338 p = make_relative_prefix (plugin_program_name, 339 BINDIR, 340 plugin_dir); 341 free (plugin_dir); 342 plugin_dir = NULL; 343 344 d = opendir (p); 345 if (!d) 346 goto out; 347 348 while ((ent = readdir (d))) 349 { 350 char *full_name; 351 struct stat s; 352 int valid_plugin; 353 354 full_name = concat (p, "/", ent->d_name, NULL); 355 if (stat(full_name, &s) == 0 && S_ISREG (s.st_mode)) 356 found = try_load_plugin (full_name, abfd, &valid_plugin); 357 if (has_plugin <= 0) 358 has_plugin = valid_plugin; 359 free (full_name); 360 if (found) 361 break; 362 } 363 364 out: 365 free (p); 366 if (d) 367 closedir (d); 368 369 return found; 370 } 371 372 373 static const bfd_target * 374 bfd_plugin_object_p (bfd *abfd) 375 { 376 if (ld_plugin_object_p) 377 return ld_plugin_object_p (abfd); 378 379 if (abfd->plugin_format == bfd_plugin_unknown && !load_plugin (abfd)) 380 return NULL; 381 382 return abfd->plugin_format == bfd_plugin_yes ? abfd->xvec : NULL; 383 } 384 385 /* Copy any private info we understand from the input bfd 386 to the output bfd. */ 387 388 static bfd_boolean 389 bfd_plugin_bfd_copy_private_bfd_data (bfd *ibfd ATTRIBUTE_UNUSED, 390 bfd *obfd ATTRIBUTE_UNUSED) 391 { 392 BFD_ASSERT (0); 393 return TRUE; 394 } 395 396 /* Copy any private info we understand from the input section 397 to the output section. */ 398 399 static bfd_boolean 400 bfd_plugin_bfd_copy_private_section_data (bfd *ibfd ATTRIBUTE_UNUSED, 401 asection *isection ATTRIBUTE_UNUSED, 402 bfd *obfd ATTRIBUTE_UNUSED, 403 asection *osection ATTRIBUTE_UNUSED) 404 { 405 BFD_ASSERT (0); 406 return TRUE; 407 } 408 409 /* Copy any private info we understand from the input symbol 410 to the output symbol. */ 411 412 static bfd_boolean 413 bfd_plugin_bfd_copy_private_symbol_data (bfd *ibfd ATTRIBUTE_UNUSED, 414 asymbol *isymbol ATTRIBUTE_UNUSED, 415 bfd *obfd ATTRIBUTE_UNUSED, 416 asymbol *osymbol ATTRIBUTE_UNUSED) 417 { 418 BFD_ASSERT (0); 419 return TRUE; 420 } 421 422 static bfd_boolean 423 bfd_plugin_bfd_print_private_bfd_data (bfd *abfd ATTRIBUTE_UNUSED, PTR ptr ATTRIBUTE_UNUSED) 424 { 425 BFD_ASSERT (0); 426 return TRUE; 427 } 428 429 static char * 430 bfd_plugin_core_file_failing_command (bfd *abfd ATTRIBUTE_UNUSED) 431 { 432 BFD_ASSERT (0); 433 return NULL; 434 } 435 436 static int 437 bfd_plugin_core_file_failing_signal (bfd *abfd ATTRIBUTE_UNUSED) 438 { 439 BFD_ASSERT (0); 440 return 0; 441 } 442 443 static int 444 bfd_plugin_core_file_pid (bfd *abfd ATTRIBUTE_UNUSED) 445 { 446 BFD_ASSERT (0); 447 return 0; 448 } 449 450 static long 451 bfd_plugin_get_symtab_upper_bound (bfd *abfd) 452 { 453 struct plugin_data_struct *plugin_data = abfd->tdata.plugin_data; 454 long nsyms = plugin_data->nsyms; 455 456 BFD_ASSERT (nsyms >= 0); 457 458 return ((nsyms + 1) * sizeof (asymbol *)); 459 } 460 461 static flagword 462 convert_flags (const struct ld_plugin_symbol *sym) 463 { 464 switch (sym->def) 465 { 466 case LDPK_DEF: 467 case LDPK_COMMON: 468 case LDPK_UNDEF: 469 return BSF_GLOBAL; 470 471 case LDPK_WEAKUNDEF: 472 case LDPK_WEAKDEF: 473 return BSF_GLOBAL | BSF_WEAK; 474 475 default: 476 BFD_ASSERT (0); 477 return 0; 478 } 479 } 480 481 static long 482 bfd_plugin_canonicalize_symtab (bfd *abfd, 483 asymbol **alocation) 484 { 485 struct plugin_data_struct *plugin_data = abfd->tdata.plugin_data; 486 long nsyms = plugin_data->nsyms; 487 const struct ld_plugin_symbol *syms = plugin_data->syms; 488 static asection fake_section; 489 static asection fake_common_section; 490 int i; 491 492 fake_section.name = ".text"; 493 fake_common_section.flags = SEC_IS_COMMON; 494 495 for (i = 0; i < nsyms; i++) 496 { 497 asymbol *s = bfd_alloc (abfd, sizeof (asymbol)); 498 499 BFD_ASSERT (s); 500 alocation[i] = s; 501 502 s->the_bfd = abfd; 503 s->name = syms[i].name; 504 s->value = 0; 505 s->flags = convert_flags (&syms[i]); 506 switch (syms[i].def) 507 { 508 case LDPK_COMMON: 509 s->section = &fake_common_section; 510 break; 511 case LDPK_UNDEF: 512 case LDPK_WEAKUNDEF: 513 s->section = bfd_und_section_ptr; 514 break; 515 case LDPK_DEF: 516 case LDPK_WEAKDEF: 517 s->section = &fake_section; 518 break; 519 default: 520 BFD_ASSERT (0); 521 } 522 523 s->udata.p = (void *) &syms[i]; 524 } 525 526 return nsyms; 527 } 528 529 static void 530 bfd_plugin_print_symbol (bfd *abfd ATTRIBUTE_UNUSED, 531 PTR afile ATTRIBUTE_UNUSED, 532 asymbol *symbol ATTRIBUTE_UNUSED, 533 bfd_print_symbol_type how ATTRIBUTE_UNUSED) 534 { 535 BFD_ASSERT (0); 536 } 537 538 static void 539 bfd_plugin_get_symbol_info (bfd *abfd ATTRIBUTE_UNUSED, 540 asymbol *symbol, 541 symbol_info *ret) 542 { 543 bfd_symbol_info (symbol, ret); 544 } 545 546 /* Make an empty symbol. */ 547 548 static asymbol * 549 bfd_plugin_make_empty_symbol (bfd *abfd) 550 { 551 asymbol *new_symbol = bfd_zalloc (abfd, sizeof (asymbol)); 552 if (new_symbol == NULL) 553 return new_symbol; 554 new_symbol->the_bfd = abfd; 555 return new_symbol; 556 } 557 558 static int 559 bfd_plugin_sizeof_headers (bfd *a ATTRIBUTE_UNUSED, 560 struct bfd_link_info *info ATTRIBUTE_UNUSED) 561 { 562 BFD_ASSERT (0); 563 return 0; 564 } 565 566 const bfd_target plugin_vec = 567 { 568 "plugin", /* Name. */ 569 bfd_target_unknown_flavour, 570 BFD_ENDIAN_LITTLE, /* Target byte order. */ 571 BFD_ENDIAN_LITTLE, /* Target headers byte order. */ 572 (HAS_RELOC | EXEC_P | /* Object flags. */ 573 HAS_LINENO | HAS_DEBUG | 574 HAS_SYMS | HAS_LOCALS | DYNAMIC | WP_TEXT | D_PAGED), 575 (SEC_CODE | SEC_DATA | SEC_ROM | SEC_HAS_CONTENTS 576 | SEC_ALLOC | SEC_LOAD | SEC_RELOC), /* Section flags. */ 577 0, /* symbol_leading_char. */ 578 '/', /* ar_pad_char. */ 579 15, /* ar_max_namelen. */ 580 255, /* match priority. */ 581 582 bfd_getl64, bfd_getl_signed_64, bfd_putl64, 583 bfd_getl32, bfd_getl_signed_32, bfd_putl32, 584 bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* data */ 585 bfd_getl64, bfd_getl_signed_64, bfd_putl64, 586 bfd_getl32, bfd_getl_signed_32, bfd_putl32, 587 bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* hdrs */ 588 589 { /* bfd_check_format. */ 590 _bfd_dummy_target, 591 bfd_plugin_object_p, 592 bfd_generic_archive_p, 593 _bfd_dummy_target 594 }, 595 { /* bfd_set_format. */ 596 bfd_false, 597 bfd_false, 598 _bfd_generic_mkarchive, 599 bfd_false, 600 }, 601 { /* bfd_write_contents. */ 602 bfd_false, 603 bfd_false, 604 _bfd_write_archive_contents, 605 bfd_false, 606 }, 607 608 BFD_JUMP_TABLE_GENERIC (bfd_plugin), 609 BFD_JUMP_TABLE_COPY (bfd_plugin), 610 BFD_JUMP_TABLE_CORE (bfd_plugin), 611 #ifdef USE_64_BIT_ARCHIVE 612 BFD_JUMP_TABLE_ARCHIVE (_bfd_archive_64_bit), 613 #else 614 BFD_JUMP_TABLE_ARCHIVE (_bfd_archive_coff), 615 #endif 616 BFD_JUMP_TABLE_SYMBOLS (bfd_plugin), 617 BFD_JUMP_TABLE_RELOCS (_bfd_norelocs), 618 BFD_JUMP_TABLE_WRITE (bfd_plugin), 619 BFD_JUMP_TABLE_LINK (bfd_plugin), 620 BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic), 621 622 NULL, 623 624 NULL /* backend_data. */ 625 }; 626 #endif /* BFD_SUPPORTS_PLUGIN */ 627