1 /* Plugin support for BFD.
2 Copyright 2009, 2010, 2011, 2012
3 Free Software Foundation, Inc.
4
5 This file is part of BFD, the Binary File Descriptor library.
6
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
11
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
20 MA 02110-1301, USA. */
21
22 #include "sysdep.h"
23 #include "bfd.h"
24
25 #if BFD_SUPPORTS_PLUGINS
26
27 #include <assert.h>
28 #ifdef HAVE_DLFCN_H
29 #include <dlfcn.h>
30 #elif defined (HAVE_WINDOWS_H)
31 #include <windows.h>
32 #else
33 #error Unknown how to handle dynamic-load-libraries.
34 #endif
35 #include <stdarg.h>
36 #include "plugin-api.h"
37 #include "plugin.h"
38 #include "libbfd.h"
39 #include "libiberty.h"
40 #include <dirent.h>
41
42 #if !defined (HAVE_DLFCN_H) && defined (HAVE_WINDOWS_H)
43
44 #define RTLD_NOW 0 /* Dummy value. */
45
46 static void *
dlopen(const char * file,int mode ATTRIBUTE_UNUSED)47 dlopen (const char *file, int mode ATTRIBUTE_UNUSED)
48 {
49 return LoadLibrary (file);
50 }
51
52 static void *
dlsym(void * handle,const char * name)53 dlsym (void *handle, const char *name)
54 {
55 return GetProcAddress (handle, name);
56 }
57
58 static int ATTRIBUTE_UNUSED
dlclose(void * handle)59 dlclose (void *handle)
60 {
61 FreeLibrary (handle);
62 return 0;
63 }
64
65 static const char *
dlerror(void)66 dlerror (void)
67 {
68 return "Unable to load DLL.";
69 }
70
71 #endif /* !defined (HAVE_DLFCN_H) && defined (HAVE_WINDOWS_H) */
72
73 #define bfd_plugin_close_and_cleanup _bfd_generic_close_and_cleanup
74 #define bfd_plugin_bfd_free_cached_info _bfd_generic_bfd_free_cached_info
75 #define bfd_plugin_new_section_hook _bfd_generic_new_section_hook
76 #define bfd_plugin_get_section_contents _bfd_generic_get_section_contents
77 #define bfd_plugin_get_section_contents_in_window _bfd_generic_get_section_contents_in_window
78 #define bfd_plugin_bfd_copy_private_header_data _bfd_generic_bfd_copy_private_header_data
79 #define bfd_plugin_bfd_merge_private_bfd_data _bfd_generic_bfd_merge_private_bfd_data
80 #define bfd_plugin_bfd_copy_private_header_data _bfd_generic_bfd_copy_private_header_data
81 #define bfd_plugin_bfd_set_private_flags _bfd_generic_bfd_set_private_flags
82 #define bfd_plugin_core_file_matches_executable_p generic_core_file_matches_executable_p
83 #define bfd_plugin_bfd_is_local_label_name _bfd_nosymbols_bfd_is_local_label_name
84 #define bfd_plugin_bfd_is_target_special_symbol ((bfd_boolean (*) (bfd *, asymbol *)) bfd_false)
85 #define bfd_plugin_get_lineno _bfd_nosymbols_get_lineno
86 #define bfd_plugin_find_nearest_line _bfd_nosymbols_find_nearest_line
87 #define bfd_plugin_find_inliner_info _bfd_nosymbols_find_inliner_info
88 #define bfd_plugin_bfd_make_debug_symbol _bfd_nosymbols_bfd_make_debug_symbol
89 #define bfd_plugin_read_minisymbols _bfd_generic_read_minisymbols
90 #define bfd_plugin_minisymbol_to_symbol _bfd_generic_minisymbol_to_symbol
91 #define bfd_plugin_set_arch_mach bfd_default_set_arch_mach
92 #define bfd_plugin_set_section_contents _bfd_generic_set_section_contents
93 #define bfd_plugin_bfd_get_relocated_section_contents bfd_generic_get_relocated_section_contents
94 #define bfd_plugin_bfd_relax_section bfd_generic_relax_section
95 #define bfd_plugin_bfd_link_hash_table_create _bfd_generic_link_hash_table_create
96 #define bfd_plugin_bfd_link_hash_table_free _bfd_generic_link_hash_table_free
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
110 static enum ld_plugin_status
message(int level ATTRIBUTE_UNUSED,const char * format,...)111 message (int level ATTRIBUTE_UNUSED,
112 const char * format, ...)
113 {
114 va_list args;
115 va_start (args, format);
116 printf ("bfd plugin: ");
117 vprintf (format, args);
118 putchar ('\n');
119 va_end (args);
120 return LDPS_OK;
121 }
122
123 /* Register a claim-file handler. */
124 static ld_plugin_claim_file_handler claim_file;
125
126 static enum ld_plugin_status
register_claim_file(ld_plugin_claim_file_handler handler)127 register_claim_file (ld_plugin_claim_file_handler handler)
128 {
129 claim_file = handler;
130 return LDPS_OK;
131 }
132
133 static enum ld_plugin_status
add_symbols(void * handle,int nsyms,const struct ld_plugin_symbol * syms)134 add_symbols (void * handle,
135 int nsyms,
136 const struct ld_plugin_symbol * syms)
137 {
138 bfd *abfd = handle;
139 struct plugin_data_struct *plugin_data =
140 bfd_alloc (abfd, sizeof (plugin_data_struct));
141
142 plugin_data->nsyms = nsyms;
143 plugin_data->syms = syms;
144
145 if (nsyms != 0)
146 abfd->flags |= HAS_SYMS;
147
148 abfd->tdata.plugin_data = plugin_data;
149 return LDPS_OK;
150 }
151
152 static const char *plugin_program_name;
153
154 void
bfd_plugin_set_program_name(const char * program_name)155 bfd_plugin_set_program_name (const char *program_name)
156 {
157 plugin_program_name = program_name;
158 }
159
160 static int
try_load_plugin(const char * pname)161 try_load_plugin (const char *pname)
162 {
163 static void *plugin_handle;
164 int tv_size = 4;
165 struct ld_plugin_tv tv[tv_size];
166 int i;
167 ld_plugin_onload onload;
168 enum ld_plugin_status status;
169
170 plugin_handle = dlopen (pname, RTLD_NOW);
171 if (!plugin_handle)
172 {
173 (*_bfd_error_handler)("%s\n", dlerror ());
174 return 0;
175 }
176
177 onload = dlsym (plugin_handle, "onload");
178 if (!onload)
179 goto err;
180
181 i = 0;
182 tv[i].tv_tag = LDPT_MESSAGE;
183 tv[i].tv_u.tv_message = message;
184
185 ++i;
186 tv[i].tv_tag = LDPT_REGISTER_CLAIM_FILE_HOOK;
187 tv[i].tv_u.tv_register_claim_file = register_claim_file;
188
189 ++i;
190 tv[i].tv_tag = LDPT_ADD_SYMBOLS;
191 tv[i].tv_u.tv_add_symbols = add_symbols;
192
193 ++i;
194 tv[i].tv_tag = LDPT_NULL;
195 tv[i].tv_u.tv_val = 0;
196
197 status = (*onload)(tv);
198
199 if (status != LDPS_OK)
200 goto err;
201
202 if (!claim_file)
203 goto err;
204
205 return 1;
206
207 err:
208 plugin_handle = NULL;
209 return 0;
210 }
211
212 static const char *plugin_name;
213
214 void
bfd_plugin_set_plugin(const char * p)215 bfd_plugin_set_plugin (const char *p)
216 {
217 plugin_name = p;
218 }
219
220 static int
load_plugin(void)221 load_plugin (void)
222 {
223 char *plugin_dir;
224 char *p;
225 DIR *d;
226 struct dirent *ent;
227 int found = 0;
228
229 if (plugin_name)
230 return try_load_plugin (plugin_name);
231
232 if (plugin_program_name == NULL)
233 return 0;
234
235 plugin_dir = concat (BINDIR, "/../lib/bfd-plugins", NULL);
236 p = make_relative_prefix (plugin_program_name,
237 BINDIR,
238 plugin_dir);
239 free (plugin_dir);
240 plugin_dir = NULL;
241
242 d = opendir (p);
243 if (!d)
244 goto out;
245
246 while ((ent = readdir (d)))
247 {
248 char *full_name;
249 struct stat s;
250
251 full_name = concat (p, "/", ent->d_name, NULL);
252 if (stat(full_name, &s) == 0 && S_ISREG (s.st_mode))
253 found = try_load_plugin (full_name);
254 free (full_name);
255 if (found)
256 break;
257 }
258
259 out:
260 free (p);
261 if (d)
262 closedir (d);
263
264 return found;
265 }
266
267
268 static const bfd_target *
bfd_plugin_object_p(bfd * abfd)269 bfd_plugin_object_p (bfd *abfd)
270 {
271 int claimed = 0;
272 struct ld_plugin_input_file file;
273 bfd *iobfd;
274 static int have_loaded = 0;
275 static int have_plugin = 0;
276
277 if (!have_loaded)
278 {
279 have_loaded = 1;
280 have_plugin = load_plugin ();
281 }
282 if (!have_plugin)
283 return NULL;
284
285 file.name = abfd->filename;
286
287 if (abfd->my_archive)
288 {
289 iobfd = abfd->my_archive;
290 file.offset = abfd->origin;
291 file.filesize = arelt_size (abfd);
292 }
293 else
294 {
295 iobfd = abfd;
296 file.offset = 0;
297 file.filesize = 0;
298 }
299
300 if (!iobfd->iostream && !bfd_open_file (iobfd))
301 return NULL;
302
303 file.fd = fileno ((FILE *) iobfd->iostream);
304
305 if (!abfd->my_archive)
306 {
307 struct stat stat_buf;
308 if (fstat (file.fd, &stat_buf))
309 return NULL;
310 file.filesize = stat_buf.st_size;
311 }
312
313 file.handle = abfd;
314 off_t cur_offset = lseek(file.fd, 0, SEEK_CUR);
315 claim_file (&file, &claimed);
316 lseek(file.fd, cur_offset, SEEK_SET);
317 if (!claimed)
318 return NULL;
319
320 return abfd->xvec;
321 }
322
323 /* Copy any private info we understand from the input bfd
324 to the output bfd. */
325
326 static bfd_boolean
bfd_plugin_bfd_copy_private_bfd_data(bfd * ibfd ATTRIBUTE_UNUSED,bfd * obfd ATTRIBUTE_UNUSED)327 bfd_plugin_bfd_copy_private_bfd_data (bfd *ibfd ATTRIBUTE_UNUSED,
328 bfd *obfd ATTRIBUTE_UNUSED)
329 {
330 BFD_ASSERT (0);
331 return TRUE;
332 }
333
334 /* Copy any private info we understand from the input section
335 to the output section. */
336
337 static bfd_boolean
bfd_plugin_bfd_copy_private_section_data(bfd * ibfd ATTRIBUTE_UNUSED,asection * isection ATTRIBUTE_UNUSED,bfd * obfd ATTRIBUTE_UNUSED,asection * osection ATTRIBUTE_UNUSED)338 bfd_plugin_bfd_copy_private_section_data (bfd *ibfd ATTRIBUTE_UNUSED,
339 asection *isection ATTRIBUTE_UNUSED,
340 bfd *obfd ATTRIBUTE_UNUSED,
341 asection *osection ATTRIBUTE_UNUSED)
342 {
343 BFD_ASSERT (0);
344 return TRUE;
345 }
346
347 /* Copy any private info we understand from the input symbol
348 to the output symbol. */
349
350 static bfd_boolean
bfd_plugin_bfd_copy_private_symbol_data(bfd * ibfd ATTRIBUTE_UNUSED,asymbol * isymbol ATTRIBUTE_UNUSED,bfd * obfd ATTRIBUTE_UNUSED,asymbol * osymbol ATTRIBUTE_UNUSED)351 bfd_plugin_bfd_copy_private_symbol_data (bfd *ibfd ATTRIBUTE_UNUSED,
352 asymbol *isymbol ATTRIBUTE_UNUSED,
353 bfd *obfd ATTRIBUTE_UNUSED,
354 asymbol *osymbol ATTRIBUTE_UNUSED)
355 {
356 BFD_ASSERT (0);
357 return TRUE;
358 }
359
360 static bfd_boolean
bfd_plugin_bfd_print_private_bfd_data(bfd * abfd ATTRIBUTE_UNUSED,PTR ptr ATTRIBUTE_UNUSED)361 bfd_plugin_bfd_print_private_bfd_data (bfd *abfd ATTRIBUTE_UNUSED, PTR ptr ATTRIBUTE_UNUSED)
362 {
363 BFD_ASSERT (0);
364 return TRUE;
365 }
366
367 static char *
bfd_plugin_core_file_failing_command(bfd * abfd ATTRIBUTE_UNUSED)368 bfd_plugin_core_file_failing_command (bfd *abfd ATTRIBUTE_UNUSED)
369 {
370 BFD_ASSERT (0);
371 return NULL;
372 }
373
374 static int
bfd_plugin_core_file_failing_signal(bfd * abfd ATTRIBUTE_UNUSED)375 bfd_plugin_core_file_failing_signal (bfd *abfd ATTRIBUTE_UNUSED)
376 {
377 BFD_ASSERT (0);
378 return 0;
379 }
380
381 static int
bfd_plugin_core_file_pid(bfd * abfd ATTRIBUTE_UNUSED)382 bfd_plugin_core_file_pid (bfd *abfd ATTRIBUTE_UNUSED)
383 {
384 BFD_ASSERT (0);
385 return 0;
386 }
387
388 static long
bfd_plugin_get_symtab_upper_bound(bfd * abfd)389 bfd_plugin_get_symtab_upper_bound (bfd *abfd)
390 {
391 struct plugin_data_struct *plugin_data = abfd->tdata.plugin_data;
392 long nsyms = plugin_data->nsyms;
393
394 BFD_ASSERT (nsyms >= 0);
395
396 return ((nsyms + 1) * sizeof (asymbol *));
397 }
398
399 static flagword
convert_flags(const struct ld_plugin_symbol * sym)400 convert_flags (const struct ld_plugin_symbol *sym)
401 {
402 switch (sym->def)
403 {
404 case LDPK_DEF:
405 case LDPK_COMMON:
406 case LDPK_UNDEF:
407 return BSF_GLOBAL;
408
409 case LDPK_WEAKUNDEF:
410 case LDPK_WEAKDEF:
411 return BSF_GLOBAL | BSF_WEAK;
412
413 default:
414 BFD_ASSERT (0);
415 return 0;
416 }
417 }
418
419 static long
bfd_plugin_canonicalize_symtab(bfd * abfd,asymbol ** alocation)420 bfd_plugin_canonicalize_symtab (bfd *abfd,
421 asymbol **alocation)
422 {
423 struct plugin_data_struct *plugin_data = abfd->tdata.plugin_data;
424 long nsyms = plugin_data->nsyms;
425 const struct ld_plugin_symbol *syms = plugin_data->syms;
426 static asection fake_section;
427 static asection fake_common_section;
428 int i;
429
430 fake_section.name = ".text";
431 fake_common_section.flags = SEC_IS_COMMON;
432
433 for (i = 0; i < nsyms; i++)
434 {
435 asymbol *s = bfd_alloc (abfd, sizeof (asymbol));
436
437 BFD_ASSERT (s);
438 alocation[i] = s;
439
440 s->the_bfd = abfd;
441 s->name = syms[i].name;
442 s->value = 0;
443 s->flags = convert_flags (&syms[i]);
444 switch (syms[i].def)
445 {
446 case LDPK_COMMON:
447 s->section = &fake_common_section;
448 break;
449 case LDPK_UNDEF:
450 case LDPK_WEAKUNDEF:
451 s->section = bfd_und_section_ptr;
452 break;
453 case LDPK_DEF:
454 case LDPK_WEAKDEF:
455 s->section = &fake_section;
456 break;
457 default:
458 BFD_ASSERT (0);
459 }
460
461 s->udata.p = (void *) &syms[i];
462 }
463
464 return nsyms;
465 }
466
467 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)468 bfd_plugin_print_symbol (bfd *abfd ATTRIBUTE_UNUSED,
469 PTR afile ATTRIBUTE_UNUSED,
470 asymbol *symbol ATTRIBUTE_UNUSED,
471 bfd_print_symbol_type how ATTRIBUTE_UNUSED)
472 {
473 BFD_ASSERT (0);
474 }
475
476 static void
bfd_plugin_get_symbol_info(bfd * abfd ATTRIBUTE_UNUSED,asymbol * symbol,symbol_info * ret)477 bfd_plugin_get_symbol_info (bfd *abfd ATTRIBUTE_UNUSED,
478 asymbol *symbol,
479 symbol_info *ret)
480 {
481 bfd_symbol_info (symbol, ret);
482 }
483
484 /* Make an empty symbol. */
485
486 static asymbol *
bfd_plugin_make_empty_symbol(bfd * abfd)487 bfd_plugin_make_empty_symbol (bfd *abfd)
488 {
489 asymbol *new_symbol = bfd_zalloc (abfd, sizeof (asymbol));
490 if (new_symbol == NULL)
491 return new_symbol;
492 new_symbol->the_bfd = abfd;
493 return new_symbol;
494 }
495
496 static int
bfd_plugin_sizeof_headers(bfd * a ATTRIBUTE_UNUSED,struct bfd_link_info * info ATTRIBUTE_UNUSED)497 bfd_plugin_sizeof_headers (bfd *a ATTRIBUTE_UNUSED,
498 struct bfd_link_info *info ATTRIBUTE_UNUSED)
499 {
500 BFD_ASSERT (0);
501 return 0;
502 }
503
504 const bfd_target plugin_vec =
505 {
506 "plugin", /* Name. */
507 bfd_target_unknown_flavour,
508 BFD_ENDIAN_LITTLE, /* Target byte order. */
509 BFD_ENDIAN_LITTLE, /* Target headers byte order. */
510 (HAS_RELOC | EXEC_P | /* Object flags. */
511 HAS_LINENO | HAS_DEBUG |
512 HAS_SYMS | HAS_LOCALS | DYNAMIC | WP_TEXT | D_PAGED),
513 (SEC_CODE | SEC_DATA | SEC_ROM | SEC_HAS_CONTENTS
514 | SEC_ALLOC | SEC_LOAD | SEC_RELOC), /* Section flags. */
515 0, /* symbol_leading_char. */
516 '/', /* ar_pad_char. */
517 15, /* ar_max_namelen. */
518 0, /* match priority. */
519
520 bfd_getl64, bfd_getl_signed_64, bfd_putl64,
521 bfd_getl32, bfd_getl_signed_32, bfd_putl32,
522 bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* data */
523 bfd_getl64, bfd_getl_signed_64, bfd_putl64,
524 bfd_getl32, bfd_getl_signed_32, bfd_putl32,
525 bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* hdrs */
526
527 { /* bfd_check_format. */
528 _bfd_dummy_target,
529 bfd_plugin_object_p,
530 bfd_generic_archive_p,
531 _bfd_dummy_target
532 },
533 { /* bfd_set_format. */
534 bfd_false,
535 bfd_false,
536 _bfd_generic_mkarchive,
537 bfd_false,
538 },
539 { /* bfd_write_contents. */
540 bfd_false,
541 bfd_false,
542 _bfd_write_archive_contents,
543 bfd_false,
544 },
545
546 BFD_JUMP_TABLE_GENERIC (bfd_plugin),
547 BFD_JUMP_TABLE_COPY (bfd_plugin),
548 BFD_JUMP_TABLE_CORE (bfd_plugin),
549 BFD_JUMP_TABLE_ARCHIVE (_bfd_archive_coff),
550 BFD_JUMP_TABLE_SYMBOLS (bfd_plugin),
551 BFD_JUMP_TABLE_RELOCS (_bfd_norelocs),
552 BFD_JUMP_TABLE_WRITE (bfd_plugin),
553 BFD_JUMP_TABLE_LINK (bfd_plugin),
554 BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
555
556 NULL,
557
558 NULL /* backend_data. */
559 };
560 #endif /* BFD_SUPPORTS_PLUGIN */
561