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 static int 162 try_claim (bfd *abfd) 163 { 164 int claimed = 0; 165 struct ld_plugin_input_file file; 166 bfd *iobfd; 167 168 file.name = abfd->filename; 169 170 if (abfd->my_archive && !bfd_is_thin_archive (abfd->my_archive)) 171 { 172 iobfd = abfd->my_archive; 173 file.offset = abfd->origin; 174 file.filesize = arelt_size (abfd); 175 } 176 else 177 { 178 iobfd = abfd; 179 file.offset = 0; 180 file.filesize = 0; 181 } 182 183 if (!iobfd->iostream && !bfd_open_file (iobfd)) 184 return 0; 185 186 file.fd = fileno ((FILE *) iobfd->iostream); 187 188 if (!abfd->my_archive || bfd_is_thin_archive (abfd->my_archive)) 189 { 190 struct stat stat_buf; 191 if (fstat (file.fd, &stat_buf)) 192 return 0; 193 file.filesize = stat_buf.st_size; 194 } 195 196 file.handle = abfd; 197 off_t cur_offset = lseek(file.fd, 0, SEEK_CUR); 198 claim_file (&file, &claimed); 199 lseek(file.fd, cur_offset, SEEK_SET); 200 if (!claimed) 201 return 0; 202 203 return 1; 204 } 205 206 static int 207 try_load_plugin (const char *pname, bfd *abfd, int *has_plugin_p) 208 { 209 void *plugin_handle; 210 struct ld_plugin_tv tv[4]; 211 int i; 212 ld_plugin_onload onload; 213 enum ld_plugin_status status; 214 215 *has_plugin_p = 0; 216 217 plugin_handle = dlopen (pname, RTLD_NOW); 218 if (!plugin_handle) 219 { 220 (*_bfd_error_handler)("%s\n", dlerror ()); 221 return 0; 222 } 223 224 onload = dlsym (plugin_handle, "onload"); 225 if (!onload) 226 goto err; 227 228 i = 0; 229 tv[i].tv_tag = LDPT_MESSAGE; 230 tv[i].tv_u.tv_message = message; 231 232 ++i; 233 tv[i].tv_tag = LDPT_REGISTER_CLAIM_FILE_HOOK; 234 tv[i].tv_u.tv_register_claim_file = register_claim_file; 235 236 ++i; 237 tv[i].tv_tag = LDPT_ADD_SYMBOLS; 238 tv[i].tv_u.tv_add_symbols = add_symbols; 239 240 ++i; 241 tv[i].tv_tag = LDPT_NULL; 242 tv[i].tv_u.tv_val = 0; 243 244 status = (*onload)(tv); 245 246 if (status != LDPS_OK) 247 goto err; 248 249 *has_plugin_p = 1; 250 251 abfd->plugin_format = bfd_plugin_no; 252 253 if (!claim_file) 254 goto err; 255 256 if (!try_claim (abfd)) 257 goto err; 258 259 abfd->plugin_format = bfd_plugin_yes; 260 261 return 1; 262 263 err: 264 return 0; 265 } 266 267 /* There may be plugin libraries in lib/bfd-plugins. */ 268 269 static int has_plugin = -1; 270 271 static const bfd_target *(*ld_plugin_object_p) (bfd *); 272 273 static const char *plugin_name; 274 275 void 276 bfd_plugin_set_plugin (const char *p) 277 { 278 plugin_name = p; 279 has_plugin = p != NULL; 280 } 281 282 /* Return TRUE if a plugin library is used. */ 283 284 bfd_boolean 285 bfd_plugin_specified_p (void) 286 { 287 return has_plugin > 0; 288 } 289 290 /* Return TRUE if ABFD can be claimed by linker LTO plugin. */ 291 292 bfd_boolean 293 bfd_link_plugin_object_p (bfd *abfd) 294 { 295 if (ld_plugin_object_p) 296 return ld_plugin_object_p (abfd) != NULL; 297 return FALSE; 298 } 299 300 extern const bfd_target plugin_vec; 301 302 /* Return TRUE if TARGET is a pointer to plugin_vec. */ 303 304 bfd_boolean 305 bfd_plugin_target_p (const bfd_target *target) 306 { 307 return target == &plugin_vec; 308 } 309 310 /* Register OBJECT_P to be used by bfd_plugin_object_p. */ 311 312 void 313 register_ld_plugin_object_p (const bfd_target *(*object_p) (bfd *)) 314 { 315 ld_plugin_object_p = object_p; 316 } 317 318 static int 319 load_plugin (bfd *abfd) 320 { 321 char *plugin_dir; 322 char *p; 323 DIR *d; 324 struct dirent *ent; 325 int found = 0; 326 327 if (!has_plugin) 328 return found; 329 330 if (plugin_name) 331 return try_load_plugin (plugin_name, abfd, &has_plugin); 332 333 if (plugin_program_name == NULL) 334 return found; 335 336 plugin_dir = concat (BINDIR, RELPLUGINDIR, NULL); 337 p = make_relative_prefix (plugin_program_name, 338 BINDIR, 339 plugin_dir); 340 free (plugin_dir); 341 plugin_dir = NULL; 342 343 d = opendir (p); 344 if (!d) 345 goto out; 346 347 while ((ent = readdir (d))) 348 { 349 char *full_name; 350 struct stat s; 351 int valid_plugin; 352 353 full_name = concat (p, "/", ent->d_name, NULL); 354 if (stat(full_name, &s) == 0 && S_ISREG (s.st_mode)) 355 found = try_load_plugin (full_name, abfd, &valid_plugin); 356 if (has_plugin <= 0) 357 has_plugin = valid_plugin; 358 free (full_name); 359 if (found) 360 break; 361 } 362 363 out: 364 free (p); 365 if (d) 366 closedir (d); 367 368 return found; 369 } 370 371 372 static const bfd_target * 373 bfd_plugin_object_p (bfd *abfd) 374 { 375 if (ld_plugin_object_p) 376 return ld_plugin_object_p (abfd); 377 378 if (abfd->plugin_format == bfd_plugin_unknown && !load_plugin (abfd)) 379 return NULL; 380 381 return abfd->plugin_format == bfd_plugin_yes ? abfd->xvec : NULL; 382 } 383 384 /* Copy any private info we understand from the input bfd 385 to the output bfd. */ 386 387 static bfd_boolean 388 bfd_plugin_bfd_copy_private_bfd_data (bfd *ibfd ATTRIBUTE_UNUSED, 389 bfd *obfd ATTRIBUTE_UNUSED) 390 { 391 BFD_ASSERT (0); 392 return TRUE; 393 } 394 395 /* Copy any private info we understand from the input section 396 to the output section. */ 397 398 static bfd_boolean 399 bfd_plugin_bfd_copy_private_section_data (bfd *ibfd ATTRIBUTE_UNUSED, 400 asection *isection ATTRIBUTE_UNUSED, 401 bfd *obfd ATTRIBUTE_UNUSED, 402 asection *osection ATTRIBUTE_UNUSED) 403 { 404 BFD_ASSERT (0); 405 return TRUE; 406 } 407 408 /* Copy any private info we understand from the input symbol 409 to the output symbol. */ 410 411 static bfd_boolean 412 bfd_plugin_bfd_copy_private_symbol_data (bfd *ibfd ATTRIBUTE_UNUSED, 413 asymbol *isymbol ATTRIBUTE_UNUSED, 414 bfd *obfd ATTRIBUTE_UNUSED, 415 asymbol *osymbol ATTRIBUTE_UNUSED) 416 { 417 BFD_ASSERT (0); 418 return TRUE; 419 } 420 421 static bfd_boolean 422 bfd_plugin_bfd_print_private_bfd_data (bfd *abfd ATTRIBUTE_UNUSED, PTR ptr ATTRIBUTE_UNUSED) 423 { 424 BFD_ASSERT (0); 425 return TRUE; 426 } 427 428 static char * 429 bfd_plugin_core_file_failing_command (bfd *abfd ATTRIBUTE_UNUSED) 430 { 431 BFD_ASSERT (0); 432 return NULL; 433 } 434 435 static int 436 bfd_plugin_core_file_failing_signal (bfd *abfd ATTRIBUTE_UNUSED) 437 { 438 BFD_ASSERT (0); 439 return 0; 440 } 441 442 static int 443 bfd_plugin_core_file_pid (bfd *abfd ATTRIBUTE_UNUSED) 444 { 445 BFD_ASSERT (0); 446 return 0; 447 } 448 449 static long 450 bfd_plugin_get_symtab_upper_bound (bfd *abfd) 451 { 452 struct plugin_data_struct *plugin_data = abfd->tdata.plugin_data; 453 long nsyms = plugin_data->nsyms; 454 455 BFD_ASSERT (nsyms >= 0); 456 457 return ((nsyms + 1) * sizeof (asymbol *)); 458 } 459 460 static flagword 461 convert_flags (const struct ld_plugin_symbol *sym) 462 { 463 switch (sym->def) 464 { 465 case LDPK_DEF: 466 case LDPK_COMMON: 467 case LDPK_UNDEF: 468 return BSF_GLOBAL; 469 470 case LDPK_WEAKUNDEF: 471 case LDPK_WEAKDEF: 472 return BSF_GLOBAL | BSF_WEAK; 473 474 default: 475 BFD_ASSERT (0); 476 return 0; 477 } 478 } 479 480 static long 481 bfd_plugin_canonicalize_symtab (bfd *abfd, 482 asymbol **alocation) 483 { 484 struct plugin_data_struct *plugin_data = abfd->tdata.plugin_data; 485 long nsyms = plugin_data->nsyms; 486 const struct ld_plugin_symbol *syms = plugin_data->syms; 487 static asection fake_section; 488 static asection fake_common_section; 489 int i; 490 491 fake_section.name = ".text"; 492 fake_common_section.flags = SEC_IS_COMMON; 493 494 for (i = 0; i < nsyms; i++) 495 { 496 asymbol *s = bfd_alloc (abfd, sizeof (asymbol)); 497 498 BFD_ASSERT (s); 499 alocation[i] = s; 500 501 s->the_bfd = abfd; 502 s->name = syms[i].name; 503 s->value = 0; 504 s->flags = convert_flags (&syms[i]); 505 switch (syms[i].def) 506 { 507 case LDPK_COMMON: 508 s->section = &fake_common_section; 509 break; 510 case LDPK_UNDEF: 511 case LDPK_WEAKUNDEF: 512 s->section = bfd_und_section_ptr; 513 break; 514 case LDPK_DEF: 515 case LDPK_WEAKDEF: 516 s->section = &fake_section; 517 break; 518 default: 519 BFD_ASSERT (0); 520 } 521 522 s->udata.p = (void *) &syms[i]; 523 } 524 525 return nsyms; 526 } 527 528 static void 529 bfd_plugin_print_symbol (bfd *abfd ATTRIBUTE_UNUSED, 530 PTR afile ATTRIBUTE_UNUSED, 531 asymbol *symbol ATTRIBUTE_UNUSED, 532 bfd_print_symbol_type how ATTRIBUTE_UNUSED) 533 { 534 BFD_ASSERT (0); 535 } 536 537 static void 538 bfd_plugin_get_symbol_info (bfd *abfd ATTRIBUTE_UNUSED, 539 asymbol *symbol, 540 symbol_info *ret) 541 { 542 bfd_symbol_info (symbol, ret); 543 } 544 545 /* Make an empty symbol. */ 546 547 static asymbol * 548 bfd_plugin_make_empty_symbol (bfd *abfd) 549 { 550 asymbol *new_symbol = bfd_zalloc (abfd, sizeof (asymbol)); 551 if (new_symbol == NULL) 552 return new_symbol; 553 new_symbol->the_bfd = abfd; 554 return new_symbol; 555 } 556 557 static int 558 bfd_plugin_sizeof_headers (bfd *a ATTRIBUTE_UNUSED, 559 struct bfd_link_info *info ATTRIBUTE_UNUSED) 560 { 561 BFD_ASSERT (0); 562 return 0; 563 } 564 565 const bfd_target plugin_vec = 566 { 567 "plugin", /* Name. */ 568 bfd_target_unknown_flavour, 569 BFD_ENDIAN_LITTLE, /* Target byte order. */ 570 BFD_ENDIAN_LITTLE, /* Target headers byte order. */ 571 (HAS_RELOC | EXEC_P | /* Object flags. */ 572 HAS_LINENO | HAS_DEBUG | 573 HAS_SYMS | HAS_LOCALS | DYNAMIC | WP_TEXT | D_PAGED), 574 (SEC_CODE | SEC_DATA | SEC_ROM | SEC_HAS_CONTENTS 575 | SEC_ALLOC | SEC_LOAD | SEC_RELOC), /* Section flags. */ 576 0, /* symbol_leading_char. */ 577 '/', /* ar_pad_char. */ 578 15, /* ar_max_namelen. */ 579 255, /* match priority. */ 580 581 bfd_getl64, bfd_getl_signed_64, bfd_putl64, 582 bfd_getl32, bfd_getl_signed_32, bfd_putl32, 583 bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* data */ 584 bfd_getl64, bfd_getl_signed_64, bfd_putl64, 585 bfd_getl32, bfd_getl_signed_32, bfd_putl32, 586 bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* hdrs */ 587 588 { /* bfd_check_format. */ 589 _bfd_dummy_target, 590 bfd_plugin_object_p, 591 bfd_generic_archive_p, 592 _bfd_dummy_target 593 }, 594 { /* bfd_set_format. */ 595 bfd_false, 596 bfd_false, 597 _bfd_generic_mkarchive, 598 bfd_false, 599 }, 600 { /* bfd_write_contents. */ 601 bfd_false, 602 bfd_false, 603 _bfd_write_archive_contents, 604 bfd_false, 605 }, 606 607 BFD_JUMP_TABLE_GENERIC (bfd_plugin), 608 BFD_JUMP_TABLE_COPY (bfd_plugin), 609 BFD_JUMP_TABLE_CORE (bfd_plugin), 610 #ifdef USE_64_BIT_ARCHIVE 611 BFD_JUMP_TABLE_ARCHIVE (_bfd_archive_64_bit), 612 #else 613 BFD_JUMP_TABLE_ARCHIVE (_bfd_archive_coff), 614 #endif 615 BFD_JUMP_TABLE_SYMBOLS (bfd_plugin), 616 BFD_JUMP_TABLE_RELOCS (_bfd_norelocs), 617 BFD_JUMP_TABLE_WRITE (bfd_plugin), 618 BFD_JUMP_TABLE_LINK (bfd_plugin), 619 BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic), 620 621 NULL, 622 623 NULL /* backend_data. */ 624 }; 625 #endif /* BFD_SUPPORTS_PLUGIN */ 626