bfd/
[deliverable/binutils-gdb.git] / bfd / elfcode.h
1 /* ELF executable support for BFD.
2 Copyright 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
4
5 Written by Fred Fish @ Cygnus Support, from information published
6 in "UNIX System V Release 4, Programmers Guide: ANSI C and
7 Programming Support Tools". Sufficient support for gdb.
8
9 Rewritten by Mark Eichin @ Cygnus Support, from information
10 published in "System V Application Binary Interface", chapters 4
11 and 5, as well as the various "Processor Supplement" documents
12 derived from it. Added support for assembler and other object file
13 utilities. Further work done by Ken Raeburn (Cygnus Support), Michael
14 Meissner (Open Software Foundation), and Peter Hoogenboom (University
15 of Utah) to finish and extend this.
16
17 This file is part of BFD, the Binary File Descriptor library.
18
19 This program is free software; you can redistribute it and/or modify
20 it under the terms of the GNU General Public License as published by
21 the Free Software Foundation; either version 2 of the License, or
22 (at your option) any later version.
23
24 This program is distributed in the hope that it will be useful,
25 but WITHOUT ANY WARRANTY; without even the implied warranty of
26 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
27 GNU General Public License for more details.
28
29 You should have received a copy of the GNU General Public License
30 along with this program; if not, write to the Free Software
31 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
32
33 /* Problems and other issues to resolve.
34
35 (1) BFD expects there to be some fixed number of "sections" in
36 the object file. I.E. there is a "section_count" variable in the
37 bfd structure which contains the number of sections. However, ELF
38 supports multiple "views" of a file. In particular, with current
39 implementations, executable files typically have two tables, a
40 program header table and a section header table, both of which
41 partition the executable.
42
43 In ELF-speak, the "linking view" of the file uses the section header
44 table to access "sections" within the file, and the "execution view"
45 uses the program header table to access "segments" within the file.
46 "Segments" typically may contain all the data from one or more
47 "sections".
48
49 Note that the section header table is optional in ELF executables,
50 but it is this information that is most useful to gdb. If the
51 section header table is missing, then gdb should probably try
52 to make do with the program header table. (FIXME)
53
54 (2) The code in this file is compiled twice, once in 32-bit mode and
55 once in 64-bit mode. More of it should be made size-independent
56 and moved into elf.c.
57
58 (3) ELF section symbols are handled rather sloppily now. This should
59 be cleaned up, and ELF section symbols reconciled with BFD section
60 symbols.
61
62 (4) We need a published spec for 64-bit ELF. We've got some stuff here
63 that we're using for SPARC V9 64-bit chips, but don't assume that
64 it's cast in stone.
65 */
66
67 #include "bfd.h"
68 #include "sysdep.h"
69 #include "libiberty.h"
70 #include "bfdlink.h"
71 #include "libbfd.h"
72 #include "elf-bfd.h"
73
74 /* Renaming structures, typedefs, macros and functions to be size-specific. */
75 #define Elf_External_Ehdr NAME(Elf,External_Ehdr)
76 #define Elf_External_Sym NAME(Elf,External_Sym)
77 #define Elf_External_Shdr NAME(Elf,External_Shdr)
78 #define Elf_External_Phdr NAME(Elf,External_Phdr)
79 #define Elf_External_Rel NAME(Elf,External_Rel)
80 #define Elf_External_Rela NAME(Elf,External_Rela)
81 #define Elf_External_Dyn NAME(Elf,External_Dyn)
82
83 #define elf_core_file_failing_command NAME(bfd_elf,core_file_failing_command)
84 #define elf_core_file_failing_signal NAME(bfd_elf,core_file_failing_signal)
85 #define elf_core_file_matches_executable_p \
86 NAME(bfd_elf,core_file_matches_executable_p)
87 #define elf_object_p NAME(bfd_elf,object_p)
88 #define elf_core_file_p NAME(bfd_elf,core_file_p)
89 #define elf_get_symtab_upper_bound NAME(bfd_elf,get_symtab_upper_bound)
90 #define elf_get_dynamic_symtab_upper_bound \
91 NAME(bfd_elf,get_dynamic_symtab_upper_bound)
92 #define elf_swap_reloc_in NAME(bfd_elf,swap_reloc_in)
93 #define elf_swap_reloca_in NAME(bfd_elf,swap_reloca_in)
94 #define elf_swap_reloc_out NAME(bfd_elf,swap_reloc_out)
95 #define elf_swap_reloca_out NAME(bfd_elf,swap_reloca_out)
96 #define elf_swap_symbol_in NAME(bfd_elf,swap_symbol_in)
97 #define elf_swap_symbol_out NAME(bfd_elf,swap_symbol_out)
98 #define elf_swap_phdr_in NAME(bfd_elf,swap_phdr_in)
99 #define elf_swap_phdr_out NAME(bfd_elf,swap_phdr_out)
100 #define elf_swap_dyn_in NAME(bfd_elf,swap_dyn_in)
101 #define elf_swap_dyn_out NAME(bfd_elf,swap_dyn_out)
102 #define elf_get_reloc_upper_bound NAME(bfd_elf,get_reloc_upper_bound)
103 #define elf_canonicalize_reloc NAME(bfd_elf,canonicalize_reloc)
104 #define elf_slurp_symbol_table NAME(bfd_elf,slurp_symbol_table)
105 #define elf_canonicalize_symtab NAME(bfd_elf,canonicalize_symtab)
106 #define elf_canonicalize_dynamic_symtab \
107 NAME(bfd_elf,canonicalize_dynamic_symtab)
108 #define elf_get_synthetic_symtab \
109 NAME(bfd_elf,get_synthetic_symtab)
110 #define elf_make_empty_symbol NAME(bfd_elf,make_empty_symbol)
111 #define elf_get_symbol_info NAME(bfd_elf,get_symbol_info)
112 #define elf_get_lineno NAME(bfd_elf,get_lineno)
113 #define elf_set_arch_mach NAME(bfd_elf,set_arch_mach)
114 #define elf_find_nearest_line NAME(bfd_elf,find_nearest_line)
115 #define elf_sizeof_headers NAME(bfd_elf,sizeof_headers)
116 #define elf_set_section_contents NAME(bfd_elf,set_section_contents)
117 #define elf_no_info_to_howto NAME(bfd_elf,no_info_to_howto)
118 #define elf_no_info_to_howto_rel NAME(bfd_elf,no_info_to_howto_rel)
119 #define elf_find_section NAME(bfd_elf,find_section)
120 #define elf_write_shdrs_and_ehdr NAME(bfd_elf,write_shdrs_and_ehdr)
121 #define elf_write_out_phdrs NAME(bfd_elf,write_out_phdrs)
122 #define elf_write_relocs NAME(bfd_elf,write_relocs)
123 #define elf_slurp_reloc_table NAME(bfd_elf,slurp_reloc_table)
124
125 #if ARCH_SIZE == 64
126 #define ELF_R_INFO(X,Y) ELF64_R_INFO(X,Y)
127 #define ELF_R_SYM(X) ELF64_R_SYM(X)
128 #define ELF_R_TYPE(X) ELF64_R_TYPE(X)
129 #define ELFCLASS ELFCLASS64
130 #define FILE_ALIGN 8
131 #define LOG_FILE_ALIGN 3
132 #endif
133 #if ARCH_SIZE == 32
134 #define ELF_R_INFO(X,Y) ELF32_R_INFO(X,Y)
135 #define ELF_R_SYM(X) ELF32_R_SYM(X)
136 #define ELF_R_TYPE(X) ELF32_R_TYPE(X)
137 #define ELFCLASS ELFCLASS32
138 #define FILE_ALIGN 4
139 #define LOG_FILE_ALIGN 2
140 #endif
141
142 #ifdef DEBUG
143 static void elf_debug_section (int, Elf_Internal_Shdr *);
144 static void elf_debug_file (Elf_Internal_Ehdr *);
145 static char *elf_symbol_flags (flagword);
146 #endif
147 \f
148 /* Structure swapping routines */
149
150 /* Should perhaps use put_offset, put_word, etc. For now, the two versions
151 can be handled by explicitly specifying 32 bits or "the long type". */
152 #if ARCH_SIZE == 64
153 #define H_PUT_WORD H_PUT_64
154 #define H_PUT_SIGNED_WORD H_PUT_S64
155 #define H_GET_WORD H_GET_64
156 #define H_GET_SIGNED_WORD H_GET_S64
157 #endif
158 #if ARCH_SIZE == 32
159 #define H_PUT_WORD H_PUT_32
160 #define H_PUT_SIGNED_WORD H_PUT_S32
161 #define H_GET_WORD H_GET_32
162 #define H_GET_SIGNED_WORD H_GET_S32
163 #endif
164
165 /* Translate an ELF symbol in external format into an ELF symbol in internal
166 format. */
167
168 void
169 elf_swap_symbol_in (bfd *abfd,
170 const void *psrc,
171 const void *pshn,
172 Elf_Internal_Sym *dst)
173 {
174 const Elf_External_Sym *src = psrc;
175 const Elf_External_Sym_Shndx *shndx = pshn;
176 int signed_vma = get_elf_backend_data (abfd)->sign_extend_vma;
177
178 dst->st_name = H_GET_32 (abfd, src->st_name);
179 if (signed_vma)
180 dst->st_value = H_GET_SIGNED_WORD (abfd, src->st_value);
181 else
182 dst->st_value = H_GET_WORD (abfd, src->st_value);
183 dst->st_size = H_GET_WORD (abfd, src->st_size);
184 dst->st_info = H_GET_8 (abfd, src->st_info);
185 dst->st_other = H_GET_8 (abfd, src->st_other);
186 dst->st_shndx = H_GET_16 (abfd, src->st_shndx);
187 if (dst->st_shndx == SHN_XINDEX)
188 {
189 if (shndx == NULL)
190 abort ();
191 dst->st_shndx = H_GET_32 (abfd, shndx->est_shndx);
192 }
193 }
194
195 /* Translate an ELF symbol in internal format into an ELF symbol in external
196 format. */
197
198 void
199 elf_swap_symbol_out (bfd *abfd,
200 const Elf_Internal_Sym *src,
201 void *cdst,
202 void *shndx)
203 {
204 unsigned int tmp;
205 Elf_External_Sym *dst = cdst;
206 H_PUT_32 (abfd, src->st_name, dst->st_name);
207 H_PUT_WORD (abfd, src->st_value, dst->st_value);
208 H_PUT_WORD (abfd, src->st_size, dst->st_size);
209 H_PUT_8 (abfd, src->st_info, dst->st_info);
210 H_PUT_8 (abfd, src->st_other, dst->st_other);
211 tmp = src->st_shndx;
212 if (tmp > SHN_HIRESERVE)
213 {
214 if (shndx == NULL)
215 abort ();
216 H_PUT_32 (abfd, tmp, shndx);
217 tmp = SHN_XINDEX;
218 }
219 H_PUT_16 (abfd, tmp, dst->st_shndx);
220 }
221
222 /* Translate an ELF file header in external format into an ELF file header in
223 internal format. */
224
225 static void
226 elf_swap_ehdr_in (bfd *abfd,
227 const Elf_External_Ehdr *src,
228 Elf_Internal_Ehdr *dst)
229 {
230 int signed_vma = get_elf_backend_data (abfd)->sign_extend_vma;
231 memcpy (dst->e_ident, src->e_ident, EI_NIDENT);
232 dst->e_type = H_GET_16 (abfd, src->e_type);
233 dst->e_machine = H_GET_16 (abfd, src->e_machine);
234 dst->e_version = H_GET_32 (abfd, src->e_version);
235 if (signed_vma)
236 dst->e_entry = H_GET_SIGNED_WORD (abfd, src->e_entry);
237 else
238 dst->e_entry = H_GET_WORD (abfd, src->e_entry);
239 dst->e_phoff = H_GET_WORD (abfd, src->e_phoff);
240 dst->e_shoff = H_GET_WORD (abfd, src->e_shoff);
241 dst->e_flags = H_GET_32 (abfd, src->e_flags);
242 dst->e_ehsize = H_GET_16 (abfd, src->e_ehsize);
243 dst->e_phentsize = H_GET_16 (abfd, src->e_phentsize);
244 dst->e_phnum = H_GET_16 (abfd, src->e_phnum);
245 dst->e_shentsize = H_GET_16 (abfd, src->e_shentsize);
246 dst->e_shnum = H_GET_16 (abfd, src->e_shnum);
247 dst->e_shstrndx = H_GET_16 (abfd, src->e_shstrndx);
248 }
249
250 /* Translate an ELF file header in internal format into an ELF file header in
251 external format. */
252
253 static void
254 elf_swap_ehdr_out (bfd *abfd,
255 const Elf_Internal_Ehdr *src,
256 Elf_External_Ehdr *dst)
257 {
258 unsigned int tmp;
259 int signed_vma = get_elf_backend_data (abfd)->sign_extend_vma;
260 memcpy (dst->e_ident, src->e_ident, EI_NIDENT);
261 /* note that all elements of dst are *arrays of unsigned char* already... */
262 H_PUT_16 (abfd, src->e_type, dst->e_type);
263 H_PUT_16 (abfd, src->e_machine, dst->e_machine);
264 H_PUT_32 (abfd, src->e_version, dst->e_version);
265 if (signed_vma)
266 H_PUT_SIGNED_WORD (abfd, src->e_entry, dst->e_entry);
267 else
268 H_PUT_WORD (abfd, src->e_entry, dst->e_entry);
269 H_PUT_WORD (abfd, src->e_phoff, dst->e_phoff);
270 H_PUT_WORD (abfd, src->e_shoff, dst->e_shoff);
271 H_PUT_32 (abfd, src->e_flags, dst->e_flags);
272 H_PUT_16 (abfd, src->e_ehsize, dst->e_ehsize);
273 H_PUT_16 (abfd, src->e_phentsize, dst->e_phentsize);
274 H_PUT_16 (abfd, src->e_phnum, dst->e_phnum);
275 H_PUT_16 (abfd, src->e_shentsize, dst->e_shentsize);
276 tmp = src->e_shnum;
277 if (tmp >= SHN_LORESERVE)
278 tmp = SHN_UNDEF;
279 H_PUT_16 (abfd, tmp, dst->e_shnum);
280 tmp = src->e_shstrndx;
281 if (tmp >= SHN_LORESERVE)
282 tmp = SHN_XINDEX;
283 H_PUT_16 (abfd, tmp, dst->e_shstrndx);
284 }
285
286 /* Translate an ELF section header table entry in external format into an
287 ELF section header table entry in internal format. */
288
289 static void
290 elf_swap_shdr_in (bfd *abfd,
291 const Elf_External_Shdr *src,
292 Elf_Internal_Shdr *dst)
293 {
294 int signed_vma = get_elf_backend_data (abfd)->sign_extend_vma;
295
296 dst->sh_name = H_GET_32 (abfd, src->sh_name);
297 dst->sh_type = H_GET_32 (abfd, src->sh_type);
298 dst->sh_flags = H_GET_WORD (abfd, src->sh_flags);
299 if (signed_vma)
300 dst->sh_addr = H_GET_SIGNED_WORD (abfd, src->sh_addr);
301 else
302 dst->sh_addr = H_GET_WORD (abfd, src->sh_addr);
303 dst->sh_offset = H_GET_WORD (abfd, src->sh_offset);
304 dst->sh_size = H_GET_WORD (abfd, src->sh_size);
305 dst->sh_link = H_GET_32 (abfd, src->sh_link);
306 dst->sh_info = H_GET_32 (abfd, src->sh_info);
307 dst->sh_addralign = H_GET_WORD (abfd, src->sh_addralign);
308 dst->sh_entsize = H_GET_WORD (abfd, src->sh_entsize);
309 dst->bfd_section = NULL;
310 dst->contents = NULL;
311 }
312
313 /* Translate an ELF section header table entry in internal format into an
314 ELF section header table entry in external format. */
315
316 static void
317 elf_swap_shdr_out (bfd *abfd,
318 const Elf_Internal_Shdr *src,
319 Elf_External_Shdr *dst)
320 {
321 /* note that all elements of dst are *arrays of unsigned char* already... */
322 H_PUT_32 (abfd, src->sh_name, dst->sh_name);
323 H_PUT_32 (abfd, src->sh_type, dst->sh_type);
324 H_PUT_WORD (abfd, src->sh_flags, dst->sh_flags);
325 H_PUT_WORD (abfd, src->sh_addr, dst->sh_addr);
326 H_PUT_WORD (abfd, src->sh_offset, dst->sh_offset);
327 H_PUT_WORD (abfd, src->sh_size, dst->sh_size);
328 H_PUT_32 (abfd, src->sh_link, dst->sh_link);
329 H_PUT_32 (abfd, src->sh_info, dst->sh_info);
330 H_PUT_WORD (abfd, src->sh_addralign, dst->sh_addralign);
331 H_PUT_WORD (abfd, src->sh_entsize, dst->sh_entsize);
332 }
333
334 /* Translate an ELF program header table entry in external format into an
335 ELF program header table entry in internal format. */
336
337 void
338 elf_swap_phdr_in (bfd *abfd,
339 const Elf_External_Phdr *src,
340 Elf_Internal_Phdr *dst)
341 {
342 int signed_vma = get_elf_backend_data (abfd)->sign_extend_vma;
343
344 dst->p_type = H_GET_32 (abfd, src->p_type);
345 dst->p_flags = H_GET_32 (abfd, src->p_flags);
346 dst->p_offset = H_GET_WORD (abfd, src->p_offset);
347 if (signed_vma)
348 {
349 dst->p_vaddr = H_GET_SIGNED_WORD (abfd, src->p_vaddr);
350 dst->p_paddr = H_GET_SIGNED_WORD (abfd, src->p_paddr);
351 }
352 else
353 {
354 dst->p_vaddr = H_GET_WORD (abfd, src->p_vaddr);
355 dst->p_paddr = H_GET_WORD (abfd, src->p_paddr);
356 }
357 dst->p_filesz = H_GET_WORD (abfd, src->p_filesz);
358 dst->p_memsz = H_GET_WORD (abfd, src->p_memsz);
359 dst->p_align = H_GET_WORD (abfd, src->p_align);
360 }
361
362 void
363 elf_swap_phdr_out (bfd *abfd,
364 const Elf_Internal_Phdr *src,
365 Elf_External_Phdr *dst)
366 {
367 /* note that all elements of dst are *arrays of unsigned char* already... */
368 H_PUT_32 (abfd, src->p_type, dst->p_type);
369 H_PUT_WORD (abfd, src->p_offset, dst->p_offset);
370 H_PUT_WORD (abfd, src->p_vaddr, dst->p_vaddr);
371 H_PUT_WORD (abfd, src->p_paddr, dst->p_paddr);
372 H_PUT_WORD (abfd, src->p_filesz, dst->p_filesz);
373 H_PUT_WORD (abfd, src->p_memsz, dst->p_memsz);
374 H_PUT_32 (abfd, src->p_flags, dst->p_flags);
375 H_PUT_WORD (abfd, src->p_align, dst->p_align);
376 }
377
378 /* Translate an ELF reloc from external format to internal format. */
379 void
380 elf_swap_reloc_in (bfd *abfd,
381 const bfd_byte *s,
382 Elf_Internal_Rela *dst)
383 {
384 const Elf_External_Rel *src = (const Elf_External_Rel *) s;
385 dst->r_offset = H_GET_WORD (abfd, src->r_offset);
386 dst->r_info = H_GET_WORD (abfd, src->r_info);
387 dst->r_addend = 0;
388 }
389
390 void
391 elf_swap_reloca_in (bfd *abfd,
392 const bfd_byte *s,
393 Elf_Internal_Rela *dst)
394 {
395 const Elf_External_Rela *src = (const Elf_External_Rela *) s;
396 dst->r_offset = H_GET_WORD (abfd, src->r_offset);
397 dst->r_info = H_GET_WORD (abfd, src->r_info);
398 dst->r_addend = H_GET_SIGNED_WORD (abfd, src->r_addend);
399 }
400
401 /* Translate an ELF reloc from internal format to external format. */
402 void
403 elf_swap_reloc_out (bfd *abfd,
404 const Elf_Internal_Rela *src,
405 bfd_byte *d)
406 {
407 Elf_External_Rel *dst = (Elf_External_Rel *) d;
408 H_PUT_WORD (abfd, src->r_offset, dst->r_offset);
409 H_PUT_WORD (abfd, src->r_info, dst->r_info);
410 }
411
412 void
413 elf_swap_reloca_out (bfd *abfd,
414 const Elf_Internal_Rela *src,
415 bfd_byte *d)
416 {
417 Elf_External_Rela *dst = (Elf_External_Rela *) d;
418 H_PUT_WORD (abfd, src->r_offset, dst->r_offset);
419 H_PUT_WORD (abfd, src->r_info, dst->r_info);
420 H_PUT_SIGNED_WORD (abfd, src->r_addend, dst->r_addend);
421 }
422
423 void
424 elf_swap_dyn_in (bfd *abfd,
425 const void *p,
426 Elf_Internal_Dyn *dst)
427 {
428 const Elf_External_Dyn *src = p;
429
430 dst->d_tag = H_GET_WORD (abfd, src->d_tag);
431 dst->d_un.d_val = H_GET_WORD (abfd, src->d_un.d_val);
432 }
433
434 void
435 elf_swap_dyn_out (bfd *abfd,
436 const Elf_Internal_Dyn *src,
437 void *p)
438 {
439 Elf_External_Dyn *dst = p;
440
441 H_PUT_WORD (abfd, src->d_tag, dst->d_tag);
442 H_PUT_WORD (abfd, src->d_un.d_val, dst->d_un.d_val);
443 }
444 \f
445 /* ELF .o/exec file reading */
446
447 /* Begin processing a given object.
448
449 First we validate the file by reading in the ELF header and checking
450 the magic number. */
451
452 static inline bfd_boolean
453 elf_file_p (Elf_External_Ehdr *x_ehdrp)
454 {
455 return ((x_ehdrp->e_ident[EI_MAG0] == ELFMAG0)
456 && (x_ehdrp->e_ident[EI_MAG1] == ELFMAG1)
457 && (x_ehdrp->e_ident[EI_MAG2] == ELFMAG2)
458 && (x_ehdrp->e_ident[EI_MAG3] == ELFMAG3));
459 }
460
461 /* Check to see if the file associated with ABFD matches the target vector
462 that ABFD points to.
463
464 Note that we may be called several times with the same ABFD, but different
465 target vectors, most of which will not match. We have to avoid leaving
466 any side effects in ABFD, or any data it points to (like tdata), if the
467 file does not match the target vector. */
468
469 const bfd_target *
470 elf_object_p (bfd *abfd)
471 {
472 Elf_External_Ehdr x_ehdr; /* Elf file header, external form */
473 Elf_Internal_Ehdr *i_ehdrp; /* Elf file header, internal form */
474 Elf_External_Shdr x_shdr; /* Section header table entry, external form */
475 Elf_Internal_Shdr i_shdr;
476 Elf_Internal_Shdr *i_shdrp; /* Section header table, internal form */
477 unsigned int shindex;
478 char *shstrtab; /* Internal copy of section header stringtab */
479 const struct elf_backend_data *ebd;
480 struct bfd_preserve preserve;
481 asection *s;
482 bfd_size_type amt;
483
484 preserve.marker = NULL;
485
486 /* Read in the ELF header in external format. */
487
488 if (bfd_bread (&x_ehdr, sizeof (x_ehdr), abfd) != sizeof (x_ehdr))
489 {
490 if (bfd_get_error () != bfd_error_system_call)
491 goto got_wrong_format_error;
492 else
493 goto got_no_match;
494 }
495
496 /* Now check to see if we have a valid ELF file, and one that BFD can
497 make use of. The magic number must match, the address size ('class')
498 and byte-swapping must match our XVEC entry, and it must have a
499 section header table (FIXME: See comments re sections at top of this
500 file). */
501
502 if (! elf_file_p (&x_ehdr)
503 || x_ehdr.e_ident[EI_VERSION] != EV_CURRENT
504 || x_ehdr.e_ident[EI_CLASS] != ELFCLASS)
505 goto got_wrong_format_error;
506
507 /* Check that file's byte order matches xvec's */
508 switch (x_ehdr.e_ident[EI_DATA])
509 {
510 case ELFDATA2MSB: /* Big-endian */
511 if (! bfd_header_big_endian (abfd))
512 goto got_wrong_format_error;
513 break;
514 case ELFDATA2LSB: /* Little-endian */
515 if (! bfd_header_little_endian (abfd))
516 goto got_wrong_format_error;
517 break;
518 case ELFDATANONE: /* No data encoding specified */
519 default: /* Unknown data encoding specified */
520 goto got_wrong_format_error;
521 }
522
523 if (!bfd_preserve_save (abfd, &preserve))
524 goto got_no_match;
525
526 /* Allocate an instance of the elf_obj_tdata structure and hook it up to
527 the tdata pointer in the bfd. */
528
529 if (! (*abfd->xvec->_bfd_set_format[bfd_object]) (abfd))
530 goto got_no_match;
531 preserve.marker = elf_tdata (abfd);
532
533 /* Now that we know the byte order, swap in the rest of the header */
534 i_ehdrp = elf_elfheader (abfd);
535 elf_swap_ehdr_in (abfd, &x_ehdr, i_ehdrp);
536 #if DEBUG & 1
537 elf_debug_file (i_ehdrp);
538 #endif
539
540 /* Reject ET_CORE (header indicates core file, not object file) */
541 if (i_ehdrp->e_type == ET_CORE)
542 goto got_wrong_format_error;
543
544 /* If this is a relocatable file and there is no section header
545 table, then we're hosed. */
546 if (i_ehdrp->e_shoff == 0 && i_ehdrp->e_type == ET_REL)
547 goto got_wrong_format_error;
548
549 /* As a simple sanity check, verify that the what BFD thinks is the
550 size of each section header table entry actually matches the size
551 recorded in the file, but only if there are any sections. */
552 if (i_ehdrp->e_shentsize != sizeof (x_shdr) && i_ehdrp->e_shnum != 0)
553 goto got_wrong_format_error;
554
555 /* Further sanity check. */
556 if (i_ehdrp->e_shoff == 0 && i_ehdrp->e_shnum != 0)
557 goto got_wrong_format_error;
558
559 ebd = get_elf_backend_data (abfd);
560
561 /* Check that the ELF e_machine field matches what this particular
562 BFD format expects. */
563 if (ebd->elf_machine_code != i_ehdrp->e_machine
564 && (ebd->elf_machine_alt1 == 0
565 || i_ehdrp->e_machine != ebd->elf_machine_alt1)
566 && (ebd->elf_machine_alt2 == 0
567 || i_ehdrp->e_machine != ebd->elf_machine_alt2))
568 {
569 const bfd_target * const *target_ptr;
570
571 if (ebd->elf_machine_code != EM_NONE)
572 goto got_wrong_format_error;
573
574 /* This is the generic ELF target. Let it match any ELF target
575 for which we do not have a specific backend. */
576 for (target_ptr = bfd_target_vector; *target_ptr != NULL; target_ptr++)
577 {
578 const struct elf_backend_data *back;
579
580 if ((*target_ptr)->flavour != bfd_target_elf_flavour)
581 continue;
582 back = (const struct elf_backend_data *) (*target_ptr)->backend_data;
583 if (back->elf_machine_code == i_ehdrp->e_machine
584 || (back->elf_machine_alt1 != 0
585 && back->elf_machine_alt1 == i_ehdrp->e_machine)
586 || (back->elf_machine_alt2 != 0
587 && back->elf_machine_alt2 == i_ehdrp->e_machine))
588 {
589 /* target_ptr is an ELF backend which matches this
590 object file, so reject the generic ELF target. */
591 goto got_wrong_format_error;
592 }
593 }
594 }
595
596 if (i_ehdrp->e_type == ET_EXEC)
597 abfd->flags |= EXEC_P;
598 else if (i_ehdrp->e_type == ET_DYN)
599 abfd->flags |= DYNAMIC;
600
601 if (i_ehdrp->e_phnum > 0)
602 abfd->flags |= D_PAGED;
603
604 if (! bfd_default_set_arch_mach (abfd, ebd->arch, 0))
605 {
606 /* It's OK if this fails for the generic target. */
607 if (ebd->elf_machine_code != EM_NONE)
608 goto got_no_match;
609 }
610
611 /* Remember the entry point specified in the ELF file header. */
612 bfd_set_start_address (abfd, i_ehdrp->e_entry);
613
614 if (i_ehdrp->e_shoff != 0)
615 {
616 /* Seek to the section header table in the file. */
617 if (bfd_seek (abfd, (file_ptr) i_ehdrp->e_shoff, SEEK_SET) != 0)
618 goto got_no_match;
619
620 /* Read the first section header at index 0, and convert to internal
621 form. */
622 if (bfd_bread (&x_shdr, sizeof x_shdr, abfd) != sizeof (x_shdr))
623 goto got_no_match;
624 elf_swap_shdr_in (abfd, &x_shdr, &i_shdr);
625
626 /* If the section count is zero, the actual count is in the first
627 section header. */
628 if (i_ehdrp->e_shnum == SHN_UNDEF)
629 i_ehdrp->e_shnum = i_shdr.sh_size;
630
631 /* And similarly for the string table index. */
632 if (i_ehdrp->e_shstrndx == SHN_XINDEX)
633 i_ehdrp->e_shstrndx = i_shdr.sh_link;
634 }
635
636 /* Allocate space for a copy of the section header table in
637 internal form. */
638 if (i_ehdrp->e_shnum != 0)
639 {
640 Elf_Internal_Shdr *shdrp;
641 unsigned int num_sec;
642
643 amt = sizeof (*i_shdrp) * i_ehdrp->e_shnum;
644 i_shdrp = bfd_alloc (abfd, amt);
645 if (!i_shdrp)
646 goto got_no_match;
647 num_sec = i_ehdrp->e_shnum;
648 if (num_sec > SHN_LORESERVE)
649 num_sec += SHN_HIRESERVE + 1 - SHN_LORESERVE;
650 elf_numsections (abfd) = num_sec;
651 amt = sizeof (i_shdrp) * num_sec;
652 elf_elfsections (abfd) = bfd_alloc (abfd, amt);
653 if (!elf_elfsections (abfd))
654 goto got_no_match;
655
656 memcpy (i_shdrp, &i_shdr, sizeof (*i_shdrp));
657 shdrp = i_shdrp;
658 shindex = 0;
659 if (num_sec > SHN_LORESERVE)
660 {
661 for ( ; shindex < SHN_LORESERVE; shindex++)
662 elf_elfsections (abfd)[shindex] = shdrp++;
663 for ( ; shindex < SHN_HIRESERVE + 1; shindex++)
664 elf_elfsections (abfd)[shindex] = i_shdrp;
665 }
666 for ( ; shindex < num_sec; shindex++)
667 elf_elfsections (abfd)[shindex] = shdrp++;
668
669 /* Read in the rest of the section header table and convert it
670 to internal form. */
671 for (shindex = 1; shindex < i_ehdrp->e_shnum; shindex++)
672 {
673 if (bfd_bread (&x_shdr, sizeof x_shdr, abfd) != sizeof (x_shdr))
674 goto got_no_match;
675 elf_swap_shdr_in (abfd, &x_shdr, i_shdrp + shindex);
676
677 /* If the section is loaded, but not page aligned, clear
678 D_PAGED. */
679 if (i_shdrp[shindex].sh_size != 0
680 && (i_shdrp[shindex].sh_flags & SHF_ALLOC) != 0
681 && i_shdrp[shindex].sh_type != SHT_NOBITS
682 && (((i_shdrp[shindex].sh_addr - i_shdrp[shindex].sh_offset)
683 % ebd->maxpagesize)
684 != 0))
685 abfd->flags &= ~D_PAGED;
686 }
687 }
688
689 if (i_ehdrp->e_shstrndx && i_ehdrp->e_shoff)
690 {
691 if (! bfd_section_from_shdr (abfd, i_ehdrp->e_shstrndx))
692 goto got_no_match;
693 }
694
695 /* Read in the program headers. */
696 if (i_ehdrp->e_phnum == 0)
697 elf_tdata (abfd)->phdr = NULL;
698 else
699 {
700 Elf_Internal_Phdr *i_phdr;
701 unsigned int i;
702
703 amt = i_ehdrp->e_phnum * sizeof (Elf_Internal_Phdr);
704 elf_tdata (abfd)->phdr = bfd_alloc (abfd, amt);
705 if (elf_tdata (abfd)->phdr == NULL)
706 goto got_no_match;
707 if (bfd_seek (abfd, (file_ptr) i_ehdrp->e_phoff, SEEK_SET) != 0)
708 goto got_no_match;
709 i_phdr = elf_tdata (abfd)->phdr;
710 for (i = 0; i < i_ehdrp->e_phnum; i++, i_phdr++)
711 {
712 Elf_External_Phdr x_phdr;
713
714 if (bfd_bread (&x_phdr, sizeof x_phdr, abfd) != sizeof x_phdr)
715 goto got_no_match;
716 elf_swap_phdr_in (abfd, &x_phdr, i_phdr);
717 }
718 }
719
720 /* Read in the string table containing the names of the sections. We
721 will need the base pointer to this table later. */
722 /* We read this inline now, so that we don't have to go through
723 bfd_section_from_shdr with it (since this particular strtab is
724 used to find all of the ELF section names.) */
725
726 if (i_ehdrp->e_shstrndx != 0 && i_ehdrp->e_shoff)
727 {
728 unsigned int num_sec;
729
730 shstrtab = bfd_elf_get_str_section (abfd, i_ehdrp->e_shstrndx);
731 if (!shstrtab)
732 goto got_no_match;
733
734 /* Once all of the section headers have been read and converted, we
735 can start processing them. Note that the first section header is
736 a dummy placeholder entry, so we ignore it. */
737 num_sec = elf_numsections (abfd);
738 for (shindex = 1; shindex < num_sec; shindex++)
739 {
740 if (! bfd_section_from_shdr (abfd, shindex))
741 goto got_no_match;
742 if (shindex == SHN_LORESERVE - 1)
743 shindex += SHN_HIRESERVE + 1 - SHN_LORESERVE;
744 }
745 }
746
747 /* Let the backend double check the format and override global
748 information. */
749 if (ebd->elf_backend_object_p)
750 {
751 if (! (*ebd->elf_backend_object_p) (abfd))
752 goto got_wrong_format_error;
753 }
754
755 /* If we have created any reloc sections that are associated with
756 debugging sections, mark the reloc sections as debugging as well. */
757 for (s = abfd->sections; s != NULL; s = s->next)
758 {
759 if ((elf_section_data (s)->this_hdr.sh_type == SHT_REL
760 || elf_section_data (s)->this_hdr.sh_type == SHT_RELA)
761 && elf_section_data (s)->this_hdr.sh_info > 0)
762 {
763 unsigned long targ_index;
764 asection *targ_sec;
765
766 targ_index = elf_section_data (s)->this_hdr.sh_info;
767 targ_sec = bfd_section_from_elf_index (abfd, targ_index);
768 if (targ_sec != NULL
769 && (targ_sec->flags & SEC_DEBUGGING) != 0)
770 s->flags |= SEC_DEBUGGING;
771 }
772 }
773
774 bfd_preserve_finish (abfd, &preserve);
775 return abfd->xvec;
776
777 got_wrong_format_error:
778 /* There is way too much undoing of half-known state here. The caller,
779 bfd_check_format_matches, really shouldn't iterate on live bfd's to
780 check match/no-match like it does. We have to rely on that a call to
781 bfd_default_set_arch_mach with the previously known mach, undoes what
782 was done by the first bfd_default_set_arch_mach (with mach 0) here.
783 For this to work, only elf-data and the mach may be changed by the
784 target-specific elf_backend_object_p function. Note that saving the
785 whole bfd here and restoring it would be even worse; the first thing
786 you notice is that the cached bfd file position gets out of sync. */
787 bfd_set_error (bfd_error_wrong_format);
788
789 got_no_match:
790 if (preserve.marker != NULL)
791 bfd_preserve_restore (abfd, &preserve);
792 return NULL;
793 }
794 \f
795 /* ELF .o/exec file writing */
796
797 /* Write out the relocs. */
798
799 void
800 elf_write_relocs (bfd *abfd, asection *sec, void *data)
801 {
802 bfd_boolean *failedp = data;
803 Elf_Internal_Shdr *rela_hdr;
804 bfd_vma addr_offset;
805 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
806 size_t extsize;
807 bfd_byte *dst_rela;
808 unsigned int idx;
809 asymbol *last_sym;
810 int last_sym_idx;
811
812 /* If we have already failed, don't do anything. */
813 if (*failedp)
814 return;
815
816 if ((sec->flags & SEC_RELOC) == 0)
817 return;
818
819 /* The linker backend writes the relocs out itself, and sets the
820 reloc_count field to zero to inhibit writing them here. Also,
821 sometimes the SEC_RELOC flag gets set even when there aren't any
822 relocs. */
823 if (sec->reloc_count == 0)
824 return;
825
826 rela_hdr = &elf_section_data (sec)->rel_hdr;
827
828 rela_hdr->sh_size = rela_hdr->sh_entsize * sec->reloc_count;
829 rela_hdr->contents = bfd_alloc (abfd, rela_hdr->sh_size);
830 if (rela_hdr->contents == NULL)
831 {
832 *failedp = TRUE;
833 return;
834 }
835
836 /* Figure out whether the relocations are RELA or REL relocations. */
837 if (rela_hdr->sh_type == SHT_RELA)
838 {
839 swap_out = elf_swap_reloca_out;
840 extsize = sizeof (Elf_External_Rela);
841 }
842 else if (rela_hdr->sh_type == SHT_REL)
843 {
844 swap_out = elf_swap_reloc_out;
845 extsize = sizeof (Elf_External_Rel);
846 }
847 else
848 /* Every relocation section should be either an SHT_RELA or an
849 SHT_REL section. */
850 abort ();
851
852 /* The address of an ELF reloc is section relative for an object
853 file, and absolute for an executable file or shared library.
854 The address of a BFD reloc is always section relative. */
855 addr_offset = 0;
856 if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
857 addr_offset = sec->vma;
858
859 /* orelocation has the data, reloc_count has the count... */
860 last_sym = 0;
861 last_sym_idx = 0;
862 dst_rela = rela_hdr->contents;
863
864 for (idx = 0; idx < sec->reloc_count; idx++, dst_rela += extsize)
865 {
866 Elf_Internal_Rela src_rela;
867 arelent *ptr;
868 asymbol *sym;
869 int n;
870
871 ptr = sec->orelocation[idx];
872 sym = *ptr->sym_ptr_ptr;
873 if (sym == last_sym)
874 n = last_sym_idx;
875 else if (bfd_is_abs_section (sym->section) && sym->value == 0)
876 n = STN_UNDEF;
877 else
878 {
879 last_sym = sym;
880 n = _bfd_elf_symbol_from_bfd_symbol (abfd, &sym);
881 if (n < 0)
882 {
883 *failedp = TRUE;
884 return;
885 }
886 last_sym_idx = n;
887 }
888
889 if ((*ptr->sym_ptr_ptr)->the_bfd != NULL
890 && (*ptr->sym_ptr_ptr)->the_bfd->xvec != abfd->xvec
891 && ! _bfd_elf_validate_reloc (abfd, ptr))
892 {
893 *failedp = TRUE;
894 return;
895 }
896
897 src_rela.r_offset = ptr->address + addr_offset;
898 src_rela.r_info = ELF_R_INFO (n, ptr->howto->type);
899 src_rela.r_addend = ptr->addend;
900 (*swap_out) (abfd, &src_rela, dst_rela);
901 }
902 }
903
904 /* Write out the program headers. */
905
906 int
907 elf_write_out_phdrs (bfd *abfd,
908 const Elf_Internal_Phdr *phdr,
909 unsigned int count)
910 {
911 while (count--)
912 {
913 Elf_External_Phdr extphdr;
914 elf_swap_phdr_out (abfd, phdr, &extphdr);
915 if (bfd_bwrite (&extphdr, sizeof (Elf_External_Phdr), abfd)
916 != sizeof (Elf_External_Phdr))
917 return -1;
918 phdr++;
919 }
920 return 0;
921 }
922
923 /* Write out the section headers and the ELF file header. */
924
925 bfd_boolean
926 elf_write_shdrs_and_ehdr (bfd *abfd)
927 {
928 Elf_External_Ehdr x_ehdr; /* Elf file header, external form */
929 Elf_Internal_Ehdr *i_ehdrp; /* Elf file header, internal form */
930 Elf_External_Shdr *x_shdrp; /* Section header table, external form */
931 Elf_Internal_Shdr **i_shdrp; /* Section header table, internal form */
932 unsigned int count;
933 bfd_size_type amt;
934
935 i_ehdrp = elf_elfheader (abfd);
936 i_shdrp = elf_elfsections (abfd);
937
938 /* swap the header before spitting it out... */
939
940 #if DEBUG & 1
941 elf_debug_file (i_ehdrp);
942 #endif
943 elf_swap_ehdr_out (abfd, i_ehdrp, &x_ehdr);
944 amt = sizeof (x_ehdr);
945 if (bfd_seek (abfd, (file_ptr) 0, SEEK_SET) != 0
946 || bfd_bwrite (&x_ehdr, amt, abfd) != amt)
947 return FALSE;
948
949 /* Some fields in the first section header handle overflow of ehdr
950 fields. */
951 if (i_ehdrp->e_shnum >= SHN_LORESERVE)
952 i_shdrp[0]->sh_size = i_ehdrp->e_shnum;
953 if (i_ehdrp->e_shstrndx >= SHN_LORESERVE)
954 i_shdrp[0]->sh_link = i_ehdrp->e_shstrndx;
955
956 /* at this point we've concocted all the ELF sections... */
957 amt = i_ehdrp->e_shnum;
958 amt *= sizeof (*x_shdrp);
959 x_shdrp = bfd_alloc (abfd, amt);
960 if (!x_shdrp)
961 return FALSE;
962
963 for (count = 0; count < i_ehdrp->e_shnum; i_shdrp++, count++)
964 {
965 #if DEBUG & 2
966 elf_debug_section (count, *i_shdrp);
967 #endif
968 elf_swap_shdr_out (abfd, *i_shdrp, x_shdrp + count);
969
970 if (count == SHN_LORESERVE - 1)
971 i_shdrp += SHN_HIRESERVE + 1 - SHN_LORESERVE;
972 }
973 if (bfd_seek (abfd, (file_ptr) i_ehdrp->e_shoff, SEEK_SET) != 0
974 || bfd_bwrite (x_shdrp, amt, abfd) != amt)
975 return FALSE;
976
977 /* need to dump the string table too... */
978
979 return TRUE;
980 }
981
982 long
983 elf_slurp_symbol_table (bfd *abfd, asymbol **symptrs, bfd_boolean dynamic)
984 {
985 Elf_Internal_Shdr *hdr;
986 Elf_Internal_Shdr *verhdr;
987 unsigned long symcount; /* Number of external ELF symbols */
988 elf_symbol_type *sym; /* Pointer to current bfd symbol */
989 elf_symbol_type *symbase; /* Buffer for generated bfd symbols */
990 Elf_Internal_Sym *isym;
991 Elf_Internal_Sym *isymend;
992 Elf_Internal_Sym *isymbuf = NULL;
993 Elf_External_Versym *xver;
994 Elf_External_Versym *xverbuf = NULL;
995 const struct elf_backend_data *ebd;
996 bfd_size_type amt;
997
998 /* Read each raw ELF symbol, converting from external ELF form to
999 internal ELF form, and then using the information to create a
1000 canonical bfd symbol table entry.
1001
1002 Note that we allocate the initial bfd canonical symbol buffer
1003 based on a one-to-one mapping of the ELF symbols to canonical
1004 symbols. We actually use all the ELF symbols, so there will be no
1005 space left over at the end. When we have all the symbols, we
1006 build the caller's pointer vector. */
1007
1008 if (! dynamic)
1009 {
1010 hdr = &elf_tdata (abfd)->symtab_hdr;
1011 verhdr = NULL;
1012 }
1013 else
1014 {
1015 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
1016 if (elf_dynversym (abfd) == 0)
1017 verhdr = NULL;
1018 else
1019 verhdr = &elf_tdata (abfd)->dynversym_hdr;
1020 if ((elf_tdata (abfd)->dynverdef_section != 0
1021 && elf_tdata (abfd)->verdef == NULL)
1022 || (elf_tdata (abfd)->dynverref_section != 0
1023 && elf_tdata (abfd)->verref == NULL))
1024 {
1025 if (! _bfd_elf_slurp_version_tables (abfd))
1026 return -1;
1027 }
1028 }
1029
1030 ebd = get_elf_backend_data (abfd);
1031 symcount = hdr->sh_size / sizeof (Elf_External_Sym);
1032 if (symcount == 0)
1033 sym = symbase = NULL;
1034 else
1035 {
1036 isymbuf = bfd_elf_get_elf_syms (abfd, hdr, symcount, 0,
1037 NULL, NULL, NULL);
1038 if (isymbuf == NULL)
1039 return -1;
1040
1041 amt = symcount;
1042 amt *= sizeof (elf_symbol_type);
1043 symbase = bfd_zalloc (abfd, amt);
1044 if (symbase == (elf_symbol_type *) NULL)
1045 goto error_return;
1046
1047 /* Read the raw ELF version symbol information. */
1048 if (verhdr != NULL
1049 && verhdr->sh_size / sizeof (Elf_External_Versym) != symcount)
1050 {
1051 (*_bfd_error_handler)
1052 (_("%s: version count (%ld) does not match symbol count (%ld)"),
1053 abfd->filename,
1054 (long) (verhdr->sh_size / sizeof (Elf_External_Versym)),
1055 symcount);
1056
1057 /* Slurp in the symbols without the version information,
1058 since that is more helpful than just quitting. */
1059 verhdr = NULL;
1060 }
1061
1062 if (verhdr != NULL)
1063 {
1064 if (bfd_seek (abfd, verhdr->sh_offset, SEEK_SET) != 0)
1065 goto error_return;
1066
1067 xverbuf = bfd_malloc (verhdr->sh_size);
1068 if (xverbuf == NULL && verhdr->sh_size != 0)
1069 goto error_return;
1070
1071 if (bfd_bread (xverbuf, verhdr->sh_size, abfd) != verhdr->sh_size)
1072 goto error_return;
1073 }
1074
1075 /* Skip first symbol, which is a null dummy. */
1076 xver = xverbuf;
1077 if (xver != NULL)
1078 ++xver;
1079 isymend = isymbuf + symcount;
1080 for (isym = isymbuf + 1, sym = symbase; isym < isymend; isym++, sym++)
1081 {
1082 memcpy (&sym->internal_elf_sym, isym, sizeof (Elf_Internal_Sym));
1083 sym->symbol.the_bfd = abfd;
1084
1085 sym->symbol.name = bfd_elf_string_from_elf_section (abfd,
1086 hdr->sh_link,
1087 isym->st_name);
1088
1089 sym->symbol.value = isym->st_value;
1090
1091 if (isym->st_shndx == SHN_UNDEF)
1092 {
1093 sym->symbol.section = bfd_und_section_ptr;
1094 }
1095 else if (isym->st_shndx < SHN_LORESERVE
1096 || isym->st_shndx > SHN_HIRESERVE)
1097 {
1098 sym->symbol.section = bfd_section_from_elf_index (abfd,
1099 isym->st_shndx);
1100 if (sym->symbol.section == NULL)
1101 {
1102 /* This symbol is in a section for which we did not
1103 create a BFD section. Just use bfd_abs_section,
1104 although it is wrong. FIXME. */
1105 sym->symbol.section = bfd_abs_section_ptr;
1106 }
1107 }
1108 else if (isym->st_shndx == SHN_ABS)
1109 {
1110 sym->symbol.section = bfd_abs_section_ptr;
1111 }
1112 else if (isym->st_shndx == SHN_COMMON)
1113 {
1114 sym->symbol.section = bfd_com_section_ptr;
1115 /* Elf puts the alignment into the `value' field, and
1116 the size into the `size' field. BFD wants to see the
1117 size in the value field, and doesn't care (at the
1118 moment) about the alignment. */
1119 sym->symbol.value = isym->st_size;
1120 }
1121 else
1122 sym->symbol.section = bfd_abs_section_ptr;
1123
1124 /* If this is a relocatable file, then the symbol value is
1125 already section relative. */
1126 if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
1127 sym->symbol.value -= sym->symbol.section->vma;
1128
1129 switch (ELF_ST_BIND (isym->st_info))
1130 {
1131 case STB_LOCAL:
1132 sym->symbol.flags |= BSF_LOCAL;
1133 break;
1134 case STB_GLOBAL:
1135 if (isym->st_shndx != SHN_UNDEF && isym->st_shndx != SHN_COMMON)
1136 sym->symbol.flags |= BSF_GLOBAL;
1137 break;
1138 case STB_WEAK:
1139 sym->symbol.flags |= BSF_WEAK;
1140 break;
1141 }
1142
1143 switch (ELF_ST_TYPE (isym->st_info))
1144 {
1145 case STT_SECTION:
1146 sym->symbol.flags |= BSF_SECTION_SYM | BSF_DEBUGGING;
1147 break;
1148 case STT_FILE:
1149 sym->symbol.flags |= BSF_FILE | BSF_DEBUGGING;
1150 break;
1151 case STT_FUNC:
1152 sym->symbol.flags |= BSF_FUNCTION;
1153 break;
1154 case STT_OBJECT:
1155 sym->symbol.flags |= BSF_OBJECT;
1156 break;
1157 }
1158
1159 if (dynamic)
1160 sym->symbol.flags |= BSF_DYNAMIC;
1161
1162 if (xver != NULL)
1163 {
1164 Elf_Internal_Versym iversym;
1165
1166 _bfd_elf_swap_versym_in (abfd, xver, &iversym);
1167 sym->version = iversym.vs_vers;
1168 xver++;
1169 }
1170
1171 /* Do some backend-specific processing on this symbol. */
1172 if (ebd->elf_backend_symbol_processing)
1173 (*ebd->elf_backend_symbol_processing) (abfd, &sym->symbol);
1174 }
1175 }
1176
1177 /* Do some backend-specific processing on this symbol table. */
1178 if (ebd->elf_backend_symbol_table_processing)
1179 (*ebd->elf_backend_symbol_table_processing) (abfd, symbase, symcount);
1180
1181 /* We rely on the zalloc to clear out the final symbol entry. */
1182
1183 symcount = sym - symbase;
1184
1185 /* Fill in the user's symbol pointer vector if needed. */
1186 if (symptrs)
1187 {
1188 long l = symcount;
1189
1190 sym = symbase;
1191 while (l-- > 0)
1192 {
1193 *symptrs++ = &sym->symbol;
1194 sym++;
1195 }
1196 *symptrs = 0; /* Final null pointer */
1197 }
1198
1199 if (xverbuf != NULL)
1200 free (xverbuf);
1201 if (isymbuf != NULL && hdr->contents != (unsigned char *) isymbuf)
1202 free (isymbuf);
1203 return symcount;
1204
1205 error_return:
1206 if (xverbuf != NULL)
1207 free (xverbuf);
1208 if (isymbuf != NULL && hdr->contents != (unsigned char *) isymbuf)
1209 free (isymbuf);
1210 return -1;
1211 }
1212
1213 /* Read relocations for ASECT from REL_HDR. There are RELOC_COUNT of
1214 them. */
1215
1216 static bfd_boolean
1217 elf_slurp_reloc_table_from_section (bfd *abfd,
1218 asection *asect,
1219 Elf_Internal_Shdr *rel_hdr,
1220 bfd_size_type reloc_count,
1221 arelent *relents,
1222 asymbol **symbols,
1223 bfd_boolean dynamic)
1224 {
1225 const struct elf_backend_data * const ebd = get_elf_backend_data (abfd);
1226 void *allocated = NULL;
1227 bfd_byte *native_relocs;
1228 arelent *relent;
1229 unsigned int i;
1230 int entsize;
1231 unsigned int symcount;
1232
1233 allocated = bfd_malloc (rel_hdr->sh_size);
1234 if (allocated == NULL)
1235 goto error_return;
1236
1237 if (bfd_seek (abfd, rel_hdr->sh_offset, SEEK_SET) != 0
1238 || (bfd_bread (allocated, rel_hdr->sh_size, abfd)
1239 != rel_hdr->sh_size))
1240 goto error_return;
1241
1242 native_relocs = allocated;
1243
1244 entsize = rel_hdr->sh_entsize;
1245 BFD_ASSERT (entsize == sizeof (Elf_External_Rel)
1246 || entsize == sizeof (Elf_External_Rela));
1247
1248 if (dynamic)
1249 symcount = bfd_get_dynamic_symcount (abfd);
1250 else
1251 symcount = bfd_get_symcount (abfd);
1252
1253 for (i = 0, relent = relents;
1254 i < reloc_count;
1255 i++, relent++, native_relocs += entsize)
1256 {
1257 Elf_Internal_Rela rela;
1258
1259 if (entsize == sizeof (Elf_External_Rela))
1260 elf_swap_reloca_in (abfd, native_relocs, &rela);
1261 else
1262 elf_swap_reloc_in (abfd, native_relocs, &rela);
1263
1264 /* The address of an ELF reloc is section relative for an object
1265 file, and absolute for an executable file or shared library.
1266 The address of a normal BFD reloc is always section relative,
1267 and the address of a dynamic reloc is absolute.. */
1268 if ((abfd->flags & (EXEC_P | DYNAMIC)) == 0 || dynamic)
1269 relent->address = rela.r_offset;
1270 else
1271 relent->address = rela.r_offset - asect->vma;
1272
1273 if (ELF_R_SYM (rela.r_info) == 0)
1274 relent->sym_ptr_ptr = bfd_abs_section_ptr->symbol_ptr_ptr;
1275 else if (ELF_R_SYM (rela.r_info) > symcount)
1276 {
1277 (*_bfd_error_handler)
1278 (_("%s(%s): relocation %d has invalid symbol index %ld"),
1279 abfd->filename, asect->name, i, ELF_R_SYM (rela.r_info));
1280 relent->sym_ptr_ptr = bfd_abs_section.symbol_ptr_ptr;
1281 }
1282 else
1283 {
1284 asymbol **ps, *s;
1285
1286 ps = symbols + ELF_R_SYM (rela.r_info) - 1;
1287 s = *ps;
1288
1289 /* Canonicalize ELF section symbols. FIXME: Why? */
1290 if ((s->flags & BSF_SECTION_SYM) == 0)
1291 relent->sym_ptr_ptr = ps;
1292 else
1293 relent->sym_ptr_ptr = s->section->symbol_ptr_ptr;
1294 }
1295
1296 relent->addend = rela.r_addend;
1297
1298 if ((entsize == sizeof (Elf_External_Rela)
1299 && ebd->elf_info_to_howto != NULL)
1300 || ebd->elf_info_to_howto_rel == NULL)
1301 (*ebd->elf_info_to_howto) (abfd, relent, &rela);
1302 else
1303 (*ebd->elf_info_to_howto_rel) (abfd, relent, &rela);
1304 }
1305
1306 if (allocated != NULL)
1307 free (allocated);
1308
1309 return TRUE;
1310
1311 error_return:
1312 if (allocated != NULL)
1313 free (allocated);
1314 return FALSE;
1315 }
1316
1317 /* Read in and swap the external relocs. */
1318
1319 bfd_boolean
1320 elf_slurp_reloc_table (bfd *abfd,
1321 asection *asect,
1322 asymbol **symbols,
1323 bfd_boolean dynamic)
1324 {
1325 struct bfd_elf_section_data * const d = elf_section_data (asect);
1326 Elf_Internal_Shdr *rel_hdr;
1327 Elf_Internal_Shdr *rel_hdr2;
1328 bfd_size_type reloc_count;
1329 bfd_size_type reloc_count2;
1330 arelent *relents;
1331 bfd_size_type amt;
1332
1333 if (asect->relocation != NULL)
1334 return TRUE;
1335
1336 if (! dynamic)
1337 {
1338 if ((asect->flags & SEC_RELOC) == 0
1339 || asect->reloc_count == 0)
1340 return TRUE;
1341
1342 rel_hdr = &d->rel_hdr;
1343 reloc_count = NUM_SHDR_ENTRIES (rel_hdr);
1344 rel_hdr2 = d->rel_hdr2;
1345 reloc_count2 = (rel_hdr2 ? NUM_SHDR_ENTRIES (rel_hdr2) : 0);
1346
1347 BFD_ASSERT (asect->reloc_count == reloc_count + reloc_count2);
1348 BFD_ASSERT (asect->rel_filepos == rel_hdr->sh_offset
1349 || (rel_hdr2 && asect->rel_filepos == rel_hdr2->sh_offset));
1350
1351 }
1352 else
1353 {
1354 /* Note that ASECT->RELOC_COUNT tends not to be accurate in this
1355 case because relocations against this section may use the
1356 dynamic symbol table, and in that case bfd_section_from_shdr
1357 in elf.c does not update the RELOC_COUNT. */
1358 if (asect->size == 0)
1359 return TRUE;
1360
1361 rel_hdr = &d->this_hdr;
1362 reloc_count = NUM_SHDR_ENTRIES (rel_hdr);
1363 rel_hdr2 = NULL;
1364 reloc_count2 = 0;
1365 }
1366
1367 amt = (reloc_count + reloc_count2) * sizeof (arelent);
1368 relents = bfd_alloc (abfd, amt);
1369 if (relents == NULL)
1370 return FALSE;
1371
1372 if (!elf_slurp_reloc_table_from_section (abfd, asect,
1373 rel_hdr, reloc_count,
1374 relents,
1375 symbols, dynamic))
1376 return FALSE;
1377
1378 if (rel_hdr2
1379 && !elf_slurp_reloc_table_from_section (abfd, asect,
1380 rel_hdr2, reloc_count2,
1381 relents + reloc_count,
1382 symbols, dynamic))
1383 return FALSE;
1384
1385 asect->relocation = relents;
1386 return TRUE;
1387 }
1388
1389 #ifdef DEBUG
1390 static void
1391 elf_debug_section (int num, Elf_Internal_Shdr *hdr)
1392 {
1393 fprintf (stderr, "\nSection#%d '%s' 0x%.8lx\n", num,
1394 hdr->bfd_section != NULL ? hdr->bfd_section->name : "",
1395 (long) hdr);
1396 fprintf (stderr,
1397 "sh_name = %ld\tsh_type = %ld\tsh_flags = %ld\n",
1398 (long) hdr->sh_name,
1399 (long) hdr->sh_type,
1400 (long) hdr->sh_flags);
1401 fprintf (stderr,
1402 "sh_addr = %ld\tsh_offset = %ld\tsh_size = %ld\n",
1403 (long) hdr->sh_addr,
1404 (long) hdr->sh_offset,
1405 (long) hdr->sh_size);
1406 fprintf (stderr,
1407 "sh_link = %ld\tsh_info = %ld\tsh_addralign = %ld\n",
1408 (long) hdr->sh_link,
1409 (long) hdr->sh_info,
1410 (long) hdr->sh_addralign);
1411 fprintf (stderr, "sh_entsize = %ld\n",
1412 (long) hdr->sh_entsize);
1413 fflush (stderr);
1414 }
1415
1416 static void
1417 elf_debug_file (Elf_Internal_Ehdr *ehdrp)
1418 {
1419 fprintf (stderr, "e_entry = 0x%.8lx\n", (long) ehdrp->e_entry);
1420 fprintf (stderr, "e_phoff = %ld\n", (long) ehdrp->e_phoff);
1421 fprintf (stderr, "e_phnum = %ld\n", (long) ehdrp->e_phnum);
1422 fprintf (stderr, "e_phentsize = %ld\n", (long) ehdrp->e_phentsize);
1423 fprintf (stderr, "e_shoff = %ld\n", (long) ehdrp->e_shoff);
1424 fprintf (stderr, "e_shnum = %ld\n", (long) ehdrp->e_shnum);
1425 fprintf (stderr, "e_shentsize = %ld\n", (long) ehdrp->e_shentsize);
1426 }
1427
1428 static char *
1429 elf_symbol_flags (flagword flags)
1430 {
1431 static char buffer[1024];
1432
1433 buffer[0] = '\0';
1434 if (flags & BSF_LOCAL)
1435 strcat (buffer, " local");
1436
1437 if (flags & BSF_GLOBAL)
1438 strcat (buffer, " global");
1439
1440 if (flags & BSF_DEBUGGING)
1441 strcat (buffer, " debug");
1442
1443 if (flags & BSF_FUNCTION)
1444 strcat (buffer, " function");
1445
1446 if (flags & BSF_KEEP)
1447 strcat (buffer, " keep");
1448
1449 if (flags & BSF_KEEP_G)
1450 strcat (buffer, " keep_g");
1451
1452 if (flags & BSF_WEAK)
1453 strcat (buffer, " weak");
1454
1455 if (flags & BSF_SECTION_SYM)
1456 strcat (buffer, " section-sym");
1457
1458 if (flags & BSF_OLD_COMMON)
1459 strcat (buffer, " old-common");
1460
1461 if (flags & BSF_NOT_AT_END)
1462 strcat (buffer, " not-at-end");
1463
1464 if (flags & BSF_CONSTRUCTOR)
1465 strcat (buffer, " constructor");
1466
1467 if (flags & BSF_WARNING)
1468 strcat (buffer, " warning");
1469
1470 if (flags & BSF_INDIRECT)
1471 strcat (buffer, " indirect");
1472
1473 if (flags & BSF_FILE)
1474 strcat (buffer, " file");
1475
1476 if (flags & DYNAMIC)
1477 strcat (buffer, " dynamic");
1478
1479 if (flags & ~(BSF_LOCAL
1480 | BSF_GLOBAL
1481 | BSF_DEBUGGING
1482 | BSF_FUNCTION
1483 | BSF_KEEP
1484 | BSF_KEEP_G
1485 | BSF_WEAK
1486 | BSF_SECTION_SYM
1487 | BSF_OLD_COMMON
1488 | BSF_NOT_AT_END
1489 | BSF_CONSTRUCTOR
1490 | BSF_WARNING
1491 | BSF_INDIRECT
1492 | BSF_FILE
1493 | BSF_DYNAMIC))
1494 strcat (buffer, " unknown-bits");
1495
1496 return buffer;
1497 }
1498 #endif
1499 \f
1500 /* Create a new BFD as if by bfd_openr. Rather than opening a file,
1501 reconstruct an ELF file by reading the segments out of remote memory
1502 based on the ELF file header at EHDR_VMA and the ELF program headers it
1503 points to. If not null, *LOADBASEP is filled in with the difference
1504 between the VMAs from which the segments were read, and the VMAs the
1505 file headers (and hence BFD's idea of each section's VMA) put them at.
1506
1507 The function TARGET_READ_MEMORY is called to copy LEN bytes from the
1508 remote memory at target address VMA into the local buffer at MYADDR; it
1509 should return zero on success or an `errno' code on failure. TEMPL must
1510 be a BFD for a target with the word size and byte order found in the
1511 remote memory. */
1512
1513 bfd *
1514 NAME(_bfd_elf,bfd_from_remote_memory)
1515 (bfd *templ,
1516 bfd_vma ehdr_vma,
1517 bfd_vma *loadbasep,
1518 int (*target_read_memory) (bfd_vma, char *, int))
1519 {
1520 Elf_External_Ehdr x_ehdr; /* Elf file header, external form */
1521 Elf_Internal_Ehdr i_ehdr; /* Elf file header, internal form */
1522 Elf_External_Phdr *x_phdrs;
1523 Elf_Internal_Phdr *i_phdrs, *last_phdr;
1524 bfd *nbfd;
1525 struct bfd_in_memory *bim;
1526 int contents_size;
1527 char *contents;
1528 int err;
1529 unsigned int i;
1530 bfd_vma loadbase;
1531
1532 /* Read in the ELF header in external format. */
1533 err = target_read_memory (ehdr_vma, (char *) &x_ehdr, sizeof x_ehdr);
1534 if (err)
1535 {
1536 bfd_set_error (bfd_error_system_call);
1537 errno = err;
1538 return NULL;
1539 }
1540
1541 /* Now check to see if we have a valid ELF file, and one that BFD can
1542 make use of. The magic number must match, the address size ('class')
1543 and byte-swapping must match our XVEC entry. */
1544
1545 if (! elf_file_p (&x_ehdr)
1546 || x_ehdr.e_ident[EI_VERSION] != EV_CURRENT
1547 || x_ehdr.e_ident[EI_CLASS] != ELFCLASS)
1548 {
1549 bfd_set_error (bfd_error_wrong_format);
1550 return NULL;
1551 }
1552
1553 /* Check that file's byte order matches xvec's */
1554 switch (x_ehdr.e_ident[EI_DATA])
1555 {
1556 case ELFDATA2MSB: /* Big-endian */
1557 if (! bfd_header_big_endian (templ))
1558 {
1559 bfd_set_error (bfd_error_wrong_format);
1560 return NULL;
1561 }
1562 break;
1563 case ELFDATA2LSB: /* Little-endian */
1564 if (! bfd_header_little_endian (templ))
1565 {
1566 bfd_set_error (bfd_error_wrong_format);
1567 return NULL;
1568 }
1569 break;
1570 case ELFDATANONE: /* No data encoding specified */
1571 default: /* Unknown data encoding specified */
1572 bfd_set_error (bfd_error_wrong_format);
1573 return NULL;
1574 }
1575
1576 elf_swap_ehdr_in (templ, &x_ehdr, &i_ehdr);
1577
1578 /* The file header tells where to find the program headers.
1579 These are what we use to actually choose what to read. */
1580
1581 if (i_ehdr.e_phentsize != sizeof (Elf_External_Phdr) || i_ehdr.e_phnum == 0)
1582 {
1583 bfd_set_error (bfd_error_wrong_format);
1584 return NULL;
1585 }
1586
1587 x_phdrs = bfd_malloc (i_ehdr.e_phnum * (sizeof *x_phdrs + sizeof *i_phdrs));
1588 if (x_phdrs == NULL)
1589 {
1590 bfd_set_error (bfd_error_no_memory);
1591 return NULL;
1592 }
1593 err = target_read_memory (ehdr_vma + i_ehdr.e_phoff, (char *) x_phdrs,
1594 i_ehdr.e_phnum * sizeof x_phdrs[0]);
1595 if (err)
1596 {
1597 free (x_phdrs);
1598 bfd_set_error (bfd_error_system_call);
1599 errno = err;
1600 return NULL;
1601 }
1602 i_phdrs = (Elf_Internal_Phdr *) &x_phdrs[i_ehdr.e_phnum];
1603
1604 contents_size = 0;
1605 last_phdr = NULL;
1606 loadbase = ehdr_vma;
1607 for (i = 0; i < i_ehdr.e_phnum; ++i)
1608 {
1609 elf_swap_phdr_in (templ, &x_phdrs[i], &i_phdrs[i]);
1610 if (i_phdrs[i].p_type == PT_LOAD)
1611 {
1612 bfd_vma segment_end;
1613 segment_end = (i_phdrs[i].p_offset + i_phdrs[i].p_filesz
1614 + i_phdrs[i].p_align - 1) & -i_phdrs[i].p_align;
1615 if (segment_end > (bfd_vma) contents_size)
1616 contents_size = segment_end;
1617
1618 if ((i_phdrs[i].p_offset & -i_phdrs[i].p_align) == 0)
1619 loadbase = ehdr_vma - (i_phdrs[i].p_vaddr & -i_phdrs[i].p_align);
1620
1621 last_phdr = &i_phdrs[i];
1622 }
1623 }
1624 if (last_phdr == NULL)
1625 {
1626 /* There were no PT_LOAD segments, so we don't have anything to read. */
1627 free (x_phdrs);
1628 bfd_set_error (bfd_error_wrong_format);
1629 return NULL;
1630 }
1631
1632 /* Trim the last segment so we don't bother with zeros in the last page
1633 that are off the end of the file. However, if the extra bit in that
1634 page includes the section headers, keep them. */
1635 if ((bfd_vma) contents_size > last_phdr->p_offset + last_phdr->p_filesz
1636 && (bfd_vma) contents_size >= (i_ehdr.e_shoff
1637 + i_ehdr.e_shnum * i_ehdr.e_shentsize))
1638 {
1639 contents_size = last_phdr->p_offset + last_phdr->p_filesz;
1640 if ((bfd_vma) contents_size < (i_ehdr.e_shoff
1641 + i_ehdr.e_shnum * i_ehdr.e_shentsize))
1642 contents_size = i_ehdr.e_shoff + i_ehdr.e_shnum * i_ehdr.e_shentsize;
1643 }
1644 else
1645 contents_size = last_phdr->p_offset + last_phdr->p_filesz;
1646
1647 /* Now we know the size of the whole image we want read in. */
1648 contents = bfd_zmalloc (contents_size);
1649 if (contents == NULL)
1650 {
1651 free (x_phdrs);
1652 bfd_set_error (bfd_error_no_memory);
1653 return NULL;
1654 }
1655
1656 for (i = 0; i < i_ehdr.e_phnum; ++i)
1657 if (i_phdrs[i].p_type == PT_LOAD)
1658 {
1659 bfd_vma start = i_phdrs[i].p_offset & -i_phdrs[i].p_align;
1660 bfd_vma end = (i_phdrs[i].p_offset + i_phdrs[i].p_filesz
1661 + i_phdrs[i].p_align - 1) & -i_phdrs[i].p_align;
1662 if (end > (bfd_vma) contents_size)
1663 end = contents_size;
1664 err = target_read_memory ((loadbase + i_phdrs[i].p_vaddr)
1665 & -i_phdrs[i].p_align,
1666 contents + start, end - start);
1667 if (err)
1668 {
1669 free (x_phdrs);
1670 free (contents);
1671 bfd_set_error (bfd_error_system_call);
1672 errno = err;
1673 return NULL;
1674 }
1675 }
1676 free (x_phdrs);
1677
1678 /* If the segments visible in memory didn't include the section headers,
1679 then clear them from the file header. */
1680 if ((bfd_vma) contents_size < (i_ehdr.e_shoff
1681 + i_ehdr.e_shnum * i_ehdr.e_shentsize))
1682 {
1683 memset (&x_ehdr.e_shoff, 0, sizeof x_ehdr.e_shoff);
1684 memset (&x_ehdr.e_shnum, 0, sizeof x_ehdr.e_shnum);
1685 memset (&x_ehdr.e_shstrndx, 0, sizeof x_ehdr.e_shstrndx);
1686 }
1687
1688 /* This will normally have been in the first PT_LOAD segment. But it
1689 conceivably could be missing, and we might have just changed it. */
1690 memcpy (contents, &x_ehdr, sizeof x_ehdr);
1691
1692 /* Now we have a memory image of the ELF file contents. Make a BFD. */
1693 bim = bfd_malloc (sizeof (struct bfd_in_memory));
1694 if (bim == NULL)
1695 {
1696 free (contents);
1697 bfd_set_error (bfd_error_no_memory);
1698 return NULL;
1699 }
1700 nbfd = _bfd_new_bfd ();
1701 if (nbfd == NULL)
1702 {
1703 free (bim);
1704 free (contents);
1705 bfd_set_error (bfd_error_no_memory);
1706 return NULL;
1707 }
1708 nbfd->filename = "<in-memory>";
1709 nbfd->xvec = templ->xvec;
1710 bim->size = contents_size;
1711 bim->buffer = contents;
1712 nbfd->iostream = bim;
1713 nbfd->flags = BFD_IN_MEMORY;
1714 nbfd->direction = read_direction;
1715 nbfd->mtime = time (NULL);
1716 nbfd->mtime_set = TRUE;
1717
1718 if (loadbasep)
1719 *loadbasep = loadbase;
1720 return nbfd;
1721 }
1722 \f
1723 #include "elfcore.h"
1724 \f
1725 /* Size-dependent data and functions. */
1726 const struct elf_size_info NAME(_bfd_elf,size_info) = {
1727 sizeof (Elf_External_Ehdr),
1728 sizeof (Elf_External_Phdr),
1729 sizeof (Elf_External_Shdr),
1730 sizeof (Elf_External_Rel),
1731 sizeof (Elf_External_Rela),
1732 sizeof (Elf_External_Sym),
1733 sizeof (Elf_External_Dyn),
1734 sizeof (Elf_External_Note),
1735 4,
1736 1,
1737 ARCH_SIZE, LOG_FILE_ALIGN,
1738 ELFCLASS, EV_CURRENT,
1739 elf_write_out_phdrs,
1740 elf_write_shdrs_and_ehdr,
1741 elf_write_relocs,
1742 elf_swap_symbol_in,
1743 elf_swap_symbol_out,
1744 elf_slurp_reloc_table,
1745 elf_slurp_symbol_table,
1746 elf_swap_dyn_in,
1747 elf_swap_dyn_out,
1748 elf_swap_reloc_in,
1749 elf_swap_reloc_out,
1750 elf_swap_reloca_in,
1751 elf_swap_reloca_out
1752 };
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