Tidy ld/plugin.c
[deliverable/binutils-gdb.git] / bfd / plugin.c
1 /* Plugin support for BFD.
2 Copyright (C) 2009-2019 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_bool_bfd_asymbol_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_link_hide_symbol _bfd_generic_link_hide_symbol
109 #define bfd_plugin_bfd_define_start_stop bfd_generic_define_start_stop
110 #define bfd_plugin_bfd_copy_link_hash_symbol_type _bfd_generic_copy_link_hash_symbol_type
111 #define bfd_plugin_bfd_link_check_relocs _bfd_generic_link_check_relocs
112
113 static enum ld_plugin_status
114 message (int level ATTRIBUTE_UNUSED,
115 const char * format, ...)
116 {
117 va_list args;
118 va_start (args, format);
119 printf ("bfd plugin: ");
120 vprintf (format, args);
121 putchar ('\n');
122 va_end (args);
123 return LDPS_OK;
124 }
125
126 /* Register a claim-file handler. */
127 static ld_plugin_claim_file_handler claim_file = NULL;
128
129 static enum ld_plugin_status
130 register_claim_file (ld_plugin_claim_file_handler handler)
131 {
132 claim_file = handler;
133 return LDPS_OK;
134 }
135
136 static enum ld_plugin_status
137 add_symbols (void * handle,
138 int nsyms,
139 const struct ld_plugin_symbol * syms)
140 {
141 bfd *abfd = handle;
142 struct plugin_data_struct *plugin_data =
143 bfd_alloc (abfd, sizeof (plugin_data_struct));
144
145 plugin_data->nsyms = nsyms;
146 plugin_data->syms = syms;
147
148 if (nsyms != 0)
149 abfd->flags |= HAS_SYMS;
150
151 abfd->tdata.plugin_data = plugin_data;
152 return LDPS_OK;
153 }
154
155 static const char *plugin_program_name;
156
157 void
158 bfd_plugin_set_program_name (const char *program_name)
159 {
160 plugin_program_name = program_name;
161 }
162
163 int
164 bfd_plugin_open_input (bfd *ibfd, struct ld_plugin_input_file *file)
165 {
166 bfd *iobfd;
167
168 iobfd = ibfd;
169 while (iobfd->my_archive
170 && !bfd_is_thin_archive (iobfd->my_archive))
171 iobfd = iobfd->my_archive;
172 file->name = iobfd->filename;
173
174 if (!iobfd->iostream && !bfd_open_file (iobfd))
175 return 0;
176
177 /* The plugin API expects that the file descriptor won't be closed
178 and reused as done by the bfd file cache. So open it again.
179 dup isn't good enough. plugin IO uses lseek/read while BFD uses
180 fseek/fread. It isn't wise to mix the unistd and stdio calls on
181 the same underlying file descriptor. */
182 file->fd = open (file->name, O_RDONLY | O_BINARY);
183 if (file->fd < 0)
184 return 0;
185
186 if (iobfd == ibfd)
187 {
188 struct stat stat_buf;
189
190 if (fstat (file->fd, &stat_buf))
191 {
192 close(file->fd);
193 return 0;
194 }
195
196 file->offset = 0;
197 file->filesize = stat_buf.st_size;
198 }
199 else
200 {
201 file->offset = ibfd->origin;
202 file->filesize = arelt_size (ibfd);
203 }
204 return 1;
205 }
206
207 static int
208 try_claim (bfd *abfd)
209 {
210 int claimed = 0;
211 struct ld_plugin_input_file file;
212
213 file.handle = abfd;
214 if (!bfd_plugin_open_input (abfd, &file))
215 return 0;
216 if (claim_file)
217 claim_file (&file, &claimed);
218 close (file.fd);
219 return claimed;
220 }
221
222 struct plugin_list_entry
223 {
224 void * handle;
225 ld_plugin_claim_file_handler claim_file;
226 struct plugin_list_entry * next;
227 };
228
229 static struct plugin_list_entry * plugin_list = NULL;
230
231 static int
232 try_load_plugin (const char *pname, bfd *abfd, int *has_plugin_p)
233 {
234 void *plugin_handle = NULL;
235 struct ld_plugin_tv tv[4];
236 int i;
237 ld_plugin_onload onload;
238 enum ld_plugin_status status;
239 struct plugin_list_entry *plugin_list_iter;
240
241 *has_plugin_p = 0;
242
243 plugin_handle = dlopen (pname, RTLD_NOW);
244 if (!plugin_handle)
245 {
246 _bfd_error_handler ("%s\n", dlerror ());
247 return 0;
248 }
249
250 for (plugin_list_iter = plugin_list;
251 plugin_list_iter;
252 plugin_list_iter = plugin_list_iter->next)
253 {
254 if (plugin_handle == plugin_list_iter->handle)
255 {
256 dlclose (plugin_handle);
257 if (!plugin_list_iter->claim_file)
258 return 0;
259
260 register_claim_file (plugin_list_iter->claim_file);
261 goto have_claim_file;
262 }
263 }
264
265 plugin_list_iter = bfd_malloc (sizeof *plugin_list_iter);
266 if (plugin_list_iter == NULL)
267 return 0;
268 plugin_list_iter->handle = plugin_handle;
269 plugin_list_iter->claim_file = NULL;
270 plugin_list_iter->next = plugin_list;
271 plugin_list = plugin_list_iter;
272
273 onload = dlsym (plugin_handle, "onload");
274 if (!onload)
275 return 0;
276
277 i = 0;
278 tv[i].tv_tag = LDPT_MESSAGE;
279 tv[i].tv_u.tv_message = message;
280
281 ++i;
282 tv[i].tv_tag = LDPT_REGISTER_CLAIM_FILE_HOOK;
283 tv[i].tv_u.tv_register_claim_file = register_claim_file;
284
285 ++i;
286 tv[i].tv_tag = LDPT_ADD_SYMBOLS;
287 tv[i].tv_u.tv_add_symbols = add_symbols;
288
289 ++i;
290 tv[i].tv_tag = LDPT_NULL;
291 tv[i].tv_u.tv_val = 0;
292
293 status = (*onload)(tv);
294
295 if (status != LDPS_OK)
296 return 0;
297
298 plugin_list_iter->claim_file = claim_file;
299
300 have_claim_file:
301 *has_plugin_p = 1;
302
303 abfd->plugin_format = bfd_plugin_no;
304
305 if (!claim_file)
306 return 0;
307
308 if (!try_claim (abfd))
309 return 0;
310
311 abfd->plugin_format = bfd_plugin_yes;
312 return 1;
313 }
314
315 /* There may be plugin libraries in lib/bfd-plugins. */
316
317 static int has_plugin = -1;
318
319 static const bfd_target *(*ld_plugin_object_p) (bfd *);
320
321 static const char *plugin_name;
322
323 void
324 bfd_plugin_set_plugin (const char *p)
325 {
326 plugin_name = p;
327 has_plugin = p != NULL;
328 }
329
330 /* Return TRUE if a plugin library is used. */
331
332 bfd_boolean
333 bfd_plugin_specified_p (void)
334 {
335 return has_plugin > 0;
336 }
337
338 /* Return TRUE if ABFD can be claimed by linker LTO plugin. */
339
340 bfd_boolean
341 bfd_link_plugin_object_p (bfd *abfd)
342 {
343 if (ld_plugin_object_p)
344 return ld_plugin_object_p (abfd) != NULL;
345 return FALSE;
346 }
347
348 extern const bfd_target plugin_vec;
349
350 /* Return TRUE if TARGET is a pointer to plugin_vec. */
351
352 bfd_boolean
353 bfd_plugin_target_p (const bfd_target *target)
354 {
355 return target == &plugin_vec;
356 }
357
358 /* Register OBJECT_P to be used by bfd_plugin_object_p. */
359
360 void
361 register_ld_plugin_object_p (const bfd_target *(*object_p) (bfd *))
362 {
363 ld_plugin_object_p = object_p;
364 }
365
366 static int
367 load_plugin (bfd *abfd)
368 {
369 char *plugin_dir;
370 char *p;
371 DIR *d;
372 struct dirent *ent;
373 int found = 0;
374
375 if (!has_plugin)
376 return found;
377
378 if (plugin_name)
379 return try_load_plugin (plugin_name, abfd, &has_plugin);
380
381 if (plugin_program_name == NULL)
382 return found;
383
384 plugin_dir = concat (BINDIR, "/../lib/bfd-plugins", NULL);
385 p = make_relative_prefix (plugin_program_name,
386 BINDIR,
387 plugin_dir);
388 free (plugin_dir);
389 plugin_dir = NULL;
390
391 d = opendir (p);
392 if (!d)
393 goto out;
394
395 while ((ent = readdir (d)))
396 {
397 char *full_name;
398 struct stat s;
399 int valid_plugin;
400
401 full_name = concat (p, "/", ent->d_name, NULL);
402 if (stat (full_name, &s) == 0 && S_ISREG (s.st_mode))
403 found = try_load_plugin (full_name, abfd, &valid_plugin);
404 if (has_plugin <= 0)
405 has_plugin = valid_plugin;
406 free (full_name);
407 if (found)
408 break;
409 }
410
411 out:
412 free (p);
413 if (d)
414 closedir (d);
415
416 return found;
417 }
418
419
420 static const bfd_target *
421 bfd_plugin_object_p (bfd *abfd)
422 {
423 if (ld_plugin_object_p)
424 return ld_plugin_object_p (abfd);
425
426 if (abfd->plugin_format == bfd_plugin_unknown && !load_plugin (abfd))
427 return NULL;
428
429 return abfd->plugin_format == bfd_plugin_yes ? abfd->xvec : NULL;
430 }
431
432 /* Copy any private info we understand from the input bfd
433 to the output bfd. */
434
435 static bfd_boolean
436 bfd_plugin_bfd_copy_private_bfd_data (bfd *ibfd ATTRIBUTE_UNUSED,
437 bfd *obfd ATTRIBUTE_UNUSED)
438 {
439 BFD_ASSERT (0);
440 return TRUE;
441 }
442
443 /* Copy any private info we understand from the input section
444 to the output section. */
445
446 static bfd_boolean
447 bfd_plugin_bfd_copy_private_section_data (bfd *ibfd ATTRIBUTE_UNUSED,
448 asection *isection ATTRIBUTE_UNUSED,
449 bfd *obfd ATTRIBUTE_UNUSED,
450 asection *osection ATTRIBUTE_UNUSED)
451 {
452 BFD_ASSERT (0);
453 return TRUE;
454 }
455
456 /* Copy any private info we understand from the input symbol
457 to the output symbol. */
458
459 static bfd_boolean
460 bfd_plugin_bfd_copy_private_symbol_data (bfd *ibfd ATTRIBUTE_UNUSED,
461 asymbol *isymbol ATTRIBUTE_UNUSED,
462 bfd *obfd ATTRIBUTE_UNUSED,
463 asymbol *osymbol ATTRIBUTE_UNUSED)
464 {
465 BFD_ASSERT (0);
466 return TRUE;
467 }
468
469 static bfd_boolean
470 bfd_plugin_bfd_print_private_bfd_data (bfd *abfd ATTRIBUTE_UNUSED, PTR ptr ATTRIBUTE_UNUSED)
471 {
472 BFD_ASSERT (0);
473 return TRUE;
474 }
475
476 static char *
477 bfd_plugin_core_file_failing_command (bfd *abfd ATTRIBUTE_UNUSED)
478 {
479 BFD_ASSERT (0);
480 return NULL;
481 }
482
483 static int
484 bfd_plugin_core_file_failing_signal (bfd *abfd ATTRIBUTE_UNUSED)
485 {
486 BFD_ASSERT (0);
487 return 0;
488 }
489
490 static int
491 bfd_plugin_core_file_pid (bfd *abfd ATTRIBUTE_UNUSED)
492 {
493 BFD_ASSERT (0);
494 return 0;
495 }
496
497 static long
498 bfd_plugin_get_symtab_upper_bound (bfd *abfd)
499 {
500 struct plugin_data_struct *plugin_data = abfd->tdata.plugin_data;
501 long nsyms = plugin_data->nsyms;
502
503 BFD_ASSERT (nsyms >= 0);
504
505 return ((nsyms + 1) * sizeof (asymbol *));
506 }
507
508 static flagword
509 convert_flags (const struct ld_plugin_symbol *sym)
510 {
511 switch (sym->def)
512 {
513 case LDPK_DEF:
514 case LDPK_COMMON:
515 case LDPK_UNDEF:
516 return BSF_GLOBAL;
517
518 case LDPK_WEAKUNDEF:
519 case LDPK_WEAKDEF:
520 return BSF_GLOBAL | BSF_WEAK;
521
522 default:
523 BFD_ASSERT (0);
524 return 0;
525 }
526 }
527
528 static long
529 bfd_plugin_canonicalize_symtab (bfd *abfd,
530 asymbol **alocation)
531 {
532 struct plugin_data_struct *plugin_data = abfd->tdata.plugin_data;
533 long nsyms = plugin_data->nsyms;
534 const struct ld_plugin_symbol *syms = plugin_data->syms;
535 static asection fake_section
536 = BFD_FAKE_SECTION (fake_section, NULL, "plug", 0,
537 SEC_ALLOC | SEC_LOAD | SEC_CODE | SEC_HAS_CONTENTS);
538 static asection fake_common_section
539 = BFD_FAKE_SECTION (fake_common_section, NULL, "plug", 0, SEC_IS_COMMON);
540 int i;
541
542 for (i = 0; i < nsyms; i++)
543 {
544 asymbol *s = bfd_alloc (abfd, sizeof (asymbol));
545
546 BFD_ASSERT (s);
547 alocation[i] = s;
548
549 s->the_bfd = abfd;
550 s->name = syms[i].name;
551 s->value = 0;
552 s->flags = convert_flags (&syms[i]);
553 switch (syms[i].def)
554 {
555 case LDPK_COMMON:
556 s->section = &fake_common_section;
557 break;
558 case LDPK_UNDEF:
559 case LDPK_WEAKUNDEF:
560 s->section = bfd_und_section_ptr;
561 break;
562 case LDPK_DEF:
563 case LDPK_WEAKDEF:
564 s->section = &fake_section;
565 break;
566 default:
567 BFD_ASSERT (0);
568 }
569
570 s->udata.p = (void *) &syms[i];
571 }
572
573 return nsyms;
574 }
575
576 static void
577 bfd_plugin_print_symbol (bfd *abfd ATTRIBUTE_UNUSED,
578 PTR afile ATTRIBUTE_UNUSED,
579 asymbol *symbol ATTRIBUTE_UNUSED,
580 bfd_print_symbol_type how ATTRIBUTE_UNUSED)
581 {
582 BFD_ASSERT (0);
583 }
584
585 static void
586 bfd_plugin_get_symbol_info (bfd *abfd ATTRIBUTE_UNUSED,
587 asymbol *symbol,
588 symbol_info *ret)
589 {
590 bfd_symbol_info (symbol, ret);
591 }
592
593 /* Make an empty symbol. */
594
595 static asymbol *
596 bfd_plugin_make_empty_symbol (bfd *abfd)
597 {
598 asymbol *new_symbol = bfd_zalloc (abfd, sizeof (asymbol));
599 if (new_symbol == NULL)
600 return new_symbol;
601 new_symbol->the_bfd = abfd;
602 return new_symbol;
603 }
604
605 static int
606 bfd_plugin_sizeof_headers (bfd *a ATTRIBUTE_UNUSED,
607 struct bfd_link_info *info ATTRIBUTE_UNUSED)
608 {
609 BFD_ASSERT (0);
610 return 0;
611 }
612
613 const bfd_target plugin_vec =
614 {
615 "plugin", /* Name. */
616 bfd_target_unknown_flavour,
617 BFD_ENDIAN_LITTLE, /* Target byte order. */
618 BFD_ENDIAN_LITTLE, /* Target headers byte order. */
619 (HAS_RELOC | EXEC_P | /* Object flags. */
620 HAS_LINENO | HAS_DEBUG |
621 HAS_SYMS | HAS_LOCALS | DYNAMIC | WP_TEXT | D_PAGED),
622 (SEC_CODE | SEC_DATA | SEC_ROM | SEC_HAS_CONTENTS
623 | SEC_ALLOC | SEC_LOAD | SEC_RELOC), /* Section flags. */
624 0, /* symbol_leading_char. */
625 '/', /* ar_pad_char. */
626 15, /* ar_max_namelen. */
627 255, /* match priority. */
628
629 bfd_getl64, bfd_getl_signed_64, bfd_putl64,
630 bfd_getl32, bfd_getl_signed_32, bfd_putl32,
631 bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* data */
632 bfd_getl64, bfd_getl_signed_64, bfd_putl64,
633 bfd_getl32, bfd_getl_signed_32, bfd_putl32,
634 bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* hdrs */
635
636 { /* bfd_check_format. */
637 _bfd_dummy_target,
638 bfd_plugin_object_p,
639 bfd_generic_archive_p,
640 _bfd_dummy_target
641 },
642 { /* bfd_set_format. */
643 _bfd_bool_bfd_false_error,
644 _bfd_bool_bfd_false_error,
645 _bfd_generic_mkarchive,
646 _bfd_bool_bfd_false_error,
647 },
648 { /* bfd_write_contents. */
649 _bfd_bool_bfd_false_error,
650 _bfd_bool_bfd_false_error,
651 _bfd_write_archive_contents,
652 _bfd_bool_bfd_false_error,
653 },
654
655 BFD_JUMP_TABLE_GENERIC (bfd_plugin),
656 BFD_JUMP_TABLE_COPY (bfd_plugin),
657 BFD_JUMP_TABLE_CORE (bfd_plugin),
658 #ifdef USE_64_BIT_ARCHIVE
659 BFD_JUMP_TABLE_ARCHIVE (_bfd_archive_64_bit),
660 #else
661 BFD_JUMP_TABLE_ARCHIVE (_bfd_archive_coff),
662 #endif
663 BFD_JUMP_TABLE_SYMBOLS (bfd_plugin),
664 BFD_JUMP_TABLE_RELOCS (_bfd_norelocs),
665 BFD_JUMP_TABLE_WRITE (bfd_plugin),
666 BFD_JUMP_TABLE_LINK (bfd_plugin),
667 BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
668
669 NULL,
670
671 NULL /* backend_data. */
672 };
673 #endif /* BFD_SUPPORTS_PLUGIN */
This page took 0.056011 seconds and 5 git commands to generate.