* ld-elf/note-1.s: Increase .foo size.
[binutils.git] / bfd / elfcode.h
blob3c295502df70658a40202fdbedc53f515dfa0ae0
1 /* ELF executable support for BFD.
2 Copyright 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3 2001, 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
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.
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.
17 This file is part of BFD, the Binary File Descriptor library.
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.
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.
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., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */
33 /* Problems and other issues to resolve.
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.
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".
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)
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.
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.
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.
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"
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)
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)
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
142 #if DEBUG & 2
143 static void elf_debug_section (int, Elf_Internal_Shdr *);
144 #endif
145 #if DEBUG & 1
146 static void elf_debug_file (Elf_Internal_Ehdr *);
147 #endif
149 /* Structure swapping routines */
151 /* Should perhaps use put_offset, put_word, etc. For now, the two versions
152 can be handled by explicitly specifying 32 bits or "the long type". */
153 #if ARCH_SIZE == 64
154 #define H_PUT_WORD H_PUT_64
155 #define H_PUT_SIGNED_WORD H_PUT_S64
156 #define H_GET_WORD H_GET_64
157 #define H_GET_SIGNED_WORD H_GET_S64
158 #endif
159 #if ARCH_SIZE == 32
160 #define H_PUT_WORD H_PUT_32
161 #define H_PUT_SIGNED_WORD H_PUT_S32
162 #define H_GET_WORD H_GET_32
163 #define H_GET_SIGNED_WORD H_GET_S32
164 #endif
166 /* Translate an ELF symbol in external format into an ELF symbol in internal
167 format. */
169 bfd_boolean
170 elf_swap_symbol_in (bfd *abfd,
171 const void *psrc,
172 const void *pshn,
173 Elf_Internal_Sym *dst)
175 const Elf_External_Sym *src = psrc;
176 const Elf_External_Sym_Shndx *shndx = pshn;
177 int signed_vma = get_elf_backend_data (abfd)->sign_extend_vma;
179 dst->st_name = H_GET_32 (abfd, src->st_name);
180 if (signed_vma)
181 dst->st_value = H_GET_SIGNED_WORD (abfd, src->st_value);
182 else
183 dst->st_value = H_GET_WORD (abfd, src->st_value);
184 dst->st_size = H_GET_WORD (abfd, src->st_size);
185 dst->st_info = H_GET_8 (abfd, src->st_info);
186 dst->st_other = H_GET_8 (abfd, src->st_other);
187 dst->st_shndx = H_GET_16 (abfd, src->st_shndx);
188 if (dst->st_shndx == SHN_XINDEX)
190 if (shndx == NULL)
191 return FALSE;
192 dst->st_shndx = H_GET_32 (abfd, shndx->est_shndx);
194 return TRUE;
197 /* Translate an ELF symbol in internal format into an ELF symbol in external
198 format. */
200 void
201 elf_swap_symbol_out (bfd *abfd,
202 const Elf_Internal_Sym *src,
203 void *cdst,
204 void *shndx)
206 unsigned int tmp;
207 Elf_External_Sym *dst = cdst;
208 H_PUT_32 (abfd, src->st_name, dst->st_name);
209 H_PUT_WORD (abfd, src->st_value, dst->st_value);
210 H_PUT_WORD (abfd, src->st_size, dst->st_size);
211 H_PUT_8 (abfd, src->st_info, dst->st_info);
212 H_PUT_8 (abfd, src->st_other, dst->st_other);
213 tmp = src->st_shndx;
214 if (tmp > SHN_HIRESERVE)
216 if (shndx == NULL)
217 abort ();
218 H_PUT_32 (abfd, tmp, shndx);
219 tmp = SHN_XINDEX;
221 H_PUT_16 (abfd, tmp, dst->st_shndx);
224 /* Translate an ELF file header in external format into an ELF file header in
225 internal format. */
227 static void
228 elf_swap_ehdr_in (bfd *abfd,
229 const Elf_External_Ehdr *src,
230 Elf_Internal_Ehdr *dst)
232 int signed_vma = get_elf_backend_data (abfd)->sign_extend_vma;
233 memcpy (dst->e_ident, src->e_ident, EI_NIDENT);
234 dst->e_type = H_GET_16 (abfd, src->e_type);
235 dst->e_machine = H_GET_16 (abfd, src->e_machine);
236 dst->e_version = H_GET_32 (abfd, src->e_version);
237 if (signed_vma)
238 dst->e_entry = H_GET_SIGNED_WORD (abfd, src->e_entry);
239 else
240 dst->e_entry = H_GET_WORD (abfd, src->e_entry);
241 dst->e_phoff = H_GET_WORD (abfd, src->e_phoff);
242 dst->e_shoff = H_GET_WORD (abfd, src->e_shoff);
243 dst->e_flags = H_GET_32 (abfd, src->e_flags);
244 dst->e_ehsize = H_GET_16 (abfd, src->e_ehsize);
245 dst->e_phentsize = H_GET_16 (abfd, src->e_phentsize);
246 dst->e_phnum = H_GET_16 (abfd, src->e_phnum);
247 dst->e_shentsize = H_GET_16 (abfd, src->e_shentsize);
248 dst->e_shnum = H_GET_16 (abfd, src->e_shnum);
249 dst->e_shstrndx = H_GET_16 (abfd, src->e_shstrndx);
252 /* Translate an ELF file header in internal format into an ELF file header in
253 external format. */
255 static void
256 elf_swap_ehdr_out (bfd *abfd,
257 const Elf_Internal_Ehdr *src,
258 Elf_External_Ehdr *dst)
260 unsigned int tmp;
261 int signed_vma = get_elf_backend_data (abfd)->sign_extend_vma;
262 memcpy (dst->e_ident, src->e_ident, EI_NIDENT);
263 /* note that all elements of dst are *arrays of unsigned char* already... */
264 H_PUT_16 (abfd, src->e_type, dst->e_type);
265 H_PUT_16 (abfd, src->e_machine, dst->e_machine);
266 H_PUT_32 (abfd, src->e_version, dst->e_version);
267 if (signed_vma)
268 H_PUT_SIGNED_WORD (abfd, src->e_entry, dst->e_entry);
269 else
270 H_PUT_WORD (abfd, src->e_entry, dst->e_entry);
271 H_PUT_WORD (abfd, src->e_phoff, dst->e_phoff);
272 H_PUT_WORD (abfd, src->e_shoff, dst->e_shoff);
273 H_PUT_32 (abfd, src->e_flags, dst->e_flags);
274 H_PUT_16 (abfd, src->e_ehsize, dst->e_ehsize);
275 H_PUT_16 (abfd, src->e_phentsize, dst->e_phentsize);
276 H_PUT_16 (abfd, src->e_phnum, dst->e_phnum);
277 H_PUT_16 (abfd, src->e_shentsize, dst->e_shentsize);
278 tmp = src->e_shnum;
279 if (tmp >= SHN_LORESERVE)
280 tmp = SHN_UNDEF;
281 H_PUT_16 (abfd, tmp, dst->e_shnum);
282 tmp = src->e_shstrndx;
283 if (tmp >= SHN_LORESERVE)
284 tmp = SHN_XINDEX;
285 H_PUT_16 (abfd, tmp, dst->e_shstrndx);
288 /* Translate an ELF section header table entry in external format into an
289 ELF section header table entry in internal format. */
291 static void
292 elf_swap_shdr_in (bfd *abfd,
293 const Elf_External_Shdr *src,
294 Elf_Internal_Shdr *dst)
296 int signed_vma = get_elf_backend_data (abfd)->sign_extend_vma;
298 dst->sh_name = H_GET_32 (abfd, src->sh_name);
299 dst->sh_type = H_GET_32 (abfd, src->sh_type);
300 dst->sh_flags = H_GET_WORD (abfd, src->sh_flags);
301 if (signed_vma)
302 dst->sh_addr = H_GET_SIGNED_WORD (abfd, src->sh_addr);
303 else
304 dst->sh_addr = H_GET_WORD (abfd, src->sh_addr);
305 dst->sh_offset = H_GET_WORD (abfd, src->sh_offset);
306 dst->sh_size = H_GET_WORD (abfd, src->sh_size);
307 dst->sh_link = H_GET_32 (abfd, src->sh_link);
308 dst->sh_info = H_GET_32 (abfd, src->sh_info);
309 dst->sh_addralign = H_GET_WORD (abfd, src->sh_addralign);
310 dst->sh_entsize = H_GET_WORD (abfd, src->sh_entsize);
311 dst->bfd_section = NULL;
312 dst->contents = NULL;
315 /* Translate an ELF section header table entry in internal format into an
316 ELF section header table entry in external format. */
318 static void
319 elf_swap_shdr_out (bfd *abfd,
320 const Elf_Internal_Shdr *src,
321 Elf_External_Shdr *dst)
323 /* note that all elements of dst are *arrays of unsigned char* already... */
324 H_PUT_32 (abfd, src->sh_name, dst->sh_name);
325 H_PUT_32 (abfd, src->sh_type, dst->sh_type);
326 H_PUT_WORD (abfd, src->sh_flags, dst->sh_flags);
327 H_PUT_WORD (abfd, src->sh_addr, dst->sh_addr);
328 H_PUT_WORD (abfd, src->sh_offset, dst->sh_offset);
329 H_PUT_WORD (abfd, src->sh_size, dst->sh_size);
330 H_PUT_32 (abfd, src->sh_link, dst->sh_link);
331 H_PUT_32 (abfd, src->sh_info, dst->sh_info);
332 H_PUT_WORD (abfd, src->sh_addralign, dst->sh_addralign);
333 H_PUT_WORD (abfd, src->sh_entsize, dst->sh_entsize);
336 /* Translate an ELF program header table entry in external format into an
337 ELF program header table entry in internal format. */
339 void
340 elf_swap_phdr_in (bfd *abfd,
341 const Elf_External_Phdr *src,
342 Elf_Internal_Phdr *dst)
344 int signed_vma = get_elf_backend_data (abfd)->sign_extend_vma;
346 dst->p_type = H_GET_32 (abfd, src->p_type);
347 dst->p_flags = H_GET_32 (abfd, src->p_flags);
348 dst->p_offset = H_GET_WORD (abfd, src->p_offset);
349 if (signed_vma)
351 dst->p_vaddr = H_GET_SIGNED_WORD (abfd, src->p_vaddr);
352 dst->p_paddr = H_GET_SIGNED_WORD (abfd, src->p_paddr);
354 else
356 dst->p_vaddr = H_GET_WORD (abfd, src->p_vaddr);
357 dst->p_paddr = H_GET_WORD (abfd, src->p_paddr);
359 dst->p_filesz = H_GET_WORD (abfd, src->p_filesz);
360 dst->p_memsz = H_GET_WORD (abfd, src->p_memsz);
361 dst->p_align = H_GET_WORD (abfd, src->p_align);
364 void
365 elf_swap_phdr_out (bfd *abfd,
366 const Elf_Internal_Phdr *src,
367 Elf_External_Phdr *dst)
369 /* note that all elements of dst are *arrays of unsigned char* already... */
370 H_PUT_32 (abfd, src->p_type, dst->p_type);
371 H_PUT_WORD (abfd, src->p_offset, dst->p_offset);
372 H_PUT_WORD (abfd, src->p_vaddr, dst->p_vaddr);
373 H_PUT_WORD (abfd, src->p_paddr, dst->p_paddr);
374 H_PUT_WORD (abfd, src->p_filesz, dst->p_filesz);
375 H_PUT_WORD (abfd, src->p_memsz, dst->p_memsz);
376 H_PUT_32 (abfd, src->p_flags, dst->p_flags);
377 H_PUT_WORD (abfd, src->p_align, dst->p_align);
380 /* Translate an ELF reloc from external format to internal format. */
381 void
382 elf_swap_reloc_in (bfd *abfd,
383 const bfd_byte *s,
384 Elf_Internal_Rela *dst)
386 const Elf_External_Rel *src = (const Elf_External_Rel *) s;
387 dst->r_offset = H_GET_WORD (abfd, src->r_offset);
388 dst->r_info = H_GET_WORD (abfd, src->r_info);
389 dst->r_addend = 0;
392 void
393 elf_swap_reloca_in (bfd *abfd,
394 const bfd_byte *s,
395 Elf_Internal_Rela *dst)
397 const Elf_External_Rela *src = (const Elf_External_Rela *) s;
398 dst->r_offset = H_GET_WORD (abfd, src->r_offset);
399 dst->r_info = H_GET_WORD (abfd, src->r_info);
400 dst->r_addend = H_GET_SIGNED_WORD (abfd, src->r_addend);
403 /* Translate an ELF reloc from internal format to external format. */
404 void
405 elf_swap_reloc_out (bfd *abfd,
406 const Elf_Internal_Rela *src,
407 bfd_byte *d)
409 Elf_External_Rel *dst = (Elf_External_Rel *) d;
410 H_PUT_WORD (abfd, src->r_offset, dst->r_offset);
411 H_PUT_WORD (abfd, src->r_info, dst->r_info);
414 void
415 elf_swap_reloca_out (bfd *abfd,
416 const Elf_Internal_Rela *src,
417 bfd_byte *d)
419 Elf_External_Rela *dst = (Elf_External_Rela *) d;
420 H_PUT_WORD (abfd, src->r_offset, dst->r_offset);
421 H_PUT_WORD (abfd, src->r_info, dst->r_info);
422 H_PUT_SIGNED_WORD (abfd, src->r_addend, dst->r_addend);
425 void
426 elf_swap_dyn_in (bfd *abfd,
427 const void *p,
428 Elf_Internal_Dyn *dst)
430 const Elf_External_Dyn *src = p;
432 dst->d_tag = H_GET_WORD (abfd, src->d_tag);
433 dst->d_un.d_val = H_GET_WORD (abfd, src->d_un.d_val);
436 void
437 elf_swap_dyn_out (bfd *abfd,
438 const Elf_Internal_Dyn *src,
439 void *p)
441 Elf_External_Dyn *dst = p;
443 H_PUT_WORD (abfd, src->d_tag, dst->d_tag);
444 H_PUT_WORD (abfd, src->d_un.d_val, dst->d_un.d_val);
447 /* ELF .o/exec file reading */
449 /* Begin processing a given object.
451 First we validate the file by reading in the ELF header and checking
452 the magic number. */
454 static inline bfd_boolean
455 elf_file_p (Elf_External_Ehdr *x_ehdrp)
457 return ((x_ehdrp->e_ident[EI_MAG0] == ELFMAG0)
458 && (x_ehdrp->e_ident[EI_MAG1] == ELFMAG1)
459 && (x_ehdrp->e_ident[EI_MAG2] == ELFMAG2)
460 && (x_ehdrp->e_ident[EI_MAG3] == ELFMAG3));
463 /* Determines if a given section index is valid. */
465 static inline bfd_boolean
466 valid_section_index_p (unsigned index, unsigned num_sections)
468 /* Note: We allow SHN_UNDEF as a valid section index. */
469 if (index < SHN_LORESERVE || index > SHN_HIRESERVE)
470 return index < num_sections;
472 /* We disallow the use of reserved indcies, except for those
473 with OS or Application specific meaning. The test make use
474 of the knowledge that:
475 SHN_LORESERVE == SHN_LOPROC
477 SHN_HIPROC == SHN_LOOS - 1 */
478 /* XXX - Should we allow SHN_XINDEX as a valid index here ? */
479 return (index >= SHN_LOPROC && index <= SHN_HIOS);
482 /* Check to see if the file associated with ABFD matches the target vector
483 that ABFD points to.
485 Note that we may be called several times with the same ABFD, but different
486 target vectors, most of which will not match. We have to avoid leaving
487 any side effects in ABFD, or any data it points to (like tdata), if the
488 file does not match the target vector. */
490 const bfd_target *
491 elf_object_p (bfd *abfd)
493 Elf_External_Ehdr x_ehdr; /* Elf file header, external form */
494 Elf_Internal_Ehdr *i_ehdrp; /* Elf file header, internal form */
495 Elf_External_Shdr x_shdr; /* Section header table entry, external form */
496 Elf_Internal_Shdr i_shdr;
497 Elf_Internal_Shdr *i_shdrp; /* Section header table, internal form */
498 unsigned int shindex;
499 const struct elf_backend_data *ebd;
500 struct bfd_preserve preserve;
501 asection *s;
502 bfd_size_type amt;
503 const bfd_target *target;
504 const bfd_target * const *target_ptr;
506 preserve.marker = NULL;
508 /* Read in the ELF header in external format. */
510 if (bfd_bread (&x_ehdr, sizeof (x_ehdr), abfd) != sizeof (x_ehdr))
512 if (bfd_get_error () != bfd_error_system_call)
513 goto got_wrong_format_error;
514 else
515 goto got_no_match;
518 /* Now check to see if we have a valid ELF file, and one that BFD can
519 make use of. The magic number must match, the address size ('class')
520 and byte-swapping must match our XVEC entry, and it must have a
521 section header table (FIXME: See comments re sections at top of this
522 file). */
524 if (! elf_file_p (&x_ehdr)
525 || x_ehdr.e_ident[EI_VERSION] != EV_CURRENT
526 || x_ehdr.e_ident[EI_CLASS] != ELFCLASS)
527 goto got_wrong_format_error;
529 /* Check that file's byte order matches xvec's */
530 switch (x_ehdr.e_ident[EI_DATA])
532 case ELFDATA2MSB: /* Big-endian */
533 if (! bfd_header_big_endian (abfd))
534 goto got_wrong_format_error;
535 break;
536 case ELFDATA2LSB: /* Little-endian */
537 if (! bfd_header_little_endian (abfd))
538 goto got_wrong_format_error;
539 break;
540 case ELFDATANONE: /* No data encoding specified */
541 default: /* Unknown data encoding specified */
542 goto got_wrong_format_error;
545 if (!bfd_preserve_save (abfd, &preserve))
546 goto got_no_match;
548 target = abfd->xvec;
550 /* Allocate an instance of the elf_obj_tdata structure and hook it up to
551 the tdata pointer in the bfd. */
553 if (! (*target->_bfd_set_format[bfd_object]) (abfd))
554 goto got_no_match;
555 preserve.marker = elf_tdata (abfd);
557 /* Now that we know the byte order, swap in the rest of the header */
558 i_ehdrp = elf_elfheader (abfd);
559 elf_swap_ehdr_in (abfd, &x_ehdr, i_ehdrp);
560 #if DEBUG & 1
561 elf_debug_file (i_ehdrp);
562 #endif
564 /* Reject ET_CORE (header indicates core file, not object file) */
565 if (i_ehdrp->e_type == ET_CORE)
566 goto got_wrong_format_error;
568 /* If this is a relocatable file and there is no section header
569 table, then we're hosed. */
570 if (i_ehdrp->e_shoff == 0 && i_ehdrp->e_type == ET_REL)
571 goto got_wrong_format_error;
573 /* As a simple sanity check, verify that what BFD thinks is the
574 size of each section header table entry actually matches the size
575 recorded in the file, but only if there are any sections. */
576 if (i_ehdrp->e_shentsize != sizeof (x_shdr) && i_ehdrp->e_shnum != 0)
577 goto got_wrong_format_error;
579 /* Further sanity check. */
580 if (i_ehdrp->e_shoff == 0 && i_ehdrp->e_shnum != 0)
581 goto got_wrong_format_error;
583 ebd = get_elf_backend_data (abfd);
585 /* Check that the ELF e_machine field matches what this particular
586 BFD format expects. */
587 if (ebd->elf_machine_code != i_ehdrp->e_machine
588 && (ebd->elf_machine_alt1 == 0
589 || i_ehdrp->e_machine != ebd->elf_machine_alt1)
590 && (ebd->elf_machine_alt2 == 0
591 || i_ehdrp->e_machine != ebd->elf_machine_alt2))
593 if (ebd->elf_machine_code != EM_NONE)
594 goto got_wrong_format_error;
596 /* This is the generic ELF target. Let it match any ELF target
597 for which we do not have a specific backend. */
598 for (target_ptr = bfd_target_vector; *target_ptr != NULL; target_ptr++)
600 const struct elf_backend_data *back;
602 if ((*target_ptr)->flavour != bfd_target_elf_flavour)
603 continue;
604 back = (const struct elf_backend_data *) (*target_ptr)->backend_data;
605 if (back->elf_machine_code == i_ehdrp->e_machine
606 || (back->elf_machine_alt1 != 0
607 && back->elf_machine_alt1 == i_ehdrp->e_machine)
608 || (back->elf_machine_alt2 != 0
609 && back->elf_machine_alt2 == i_ehdrp->e_machine))
611 /* target_ptr is an ELF backend which matches this
612 object file, so reject the generic ELF target. */
613 goto got_wrong_format_error;
618 if (i_ehdrp->e_type == ET_EXEC)
619 abfd->flags |= EXEC_P;
620 else if (i_ehdrp->e_type == ET_DYN)
621 abfd->flags |= DYNAMIC;
623 if (i_ehdrp->e_phnum > 0)
624 abfd->flags |= D_PAGED;
626 if (! bfd_default_set_arch_mach (abfd, ebd->arch, 0))
628 /* It's OK if this fails for the generic target. */
629 if (ebd->elf_machine_code != EM_NONE)
630 goto got_no_match;
633 if (ebd->elf_machine_code != EM_NONE
634 && i_ehdrp->e_ident[EI_OSABI] != ebd->elf_osabi)
636 if (ebd->elf_osabi != ELFOSABI_NONE)
637 goto got_wrong_format_error;
639 /* This is an ELFOSABI_NONE ELF target. Let it match any ELF
640 target of the compatible machine for which we do not have a
641 backend with matching ELFOSABI. */
642 for (target_ptr = bfd_target_vector;
643 *target_ptr != NULL;
644 target_ptr++)
646 const struct elf_backend_data *back;
648 /* Skip this target and targets with incompatible byte
649 order. */
650 if (*target_ptr == target
651 || (*target_ptr)->flavour != bfd_target_elf_flavour
652 || (*target_ptr)->byteorder != target->byteorder
653 || ((*target_ptr)->header_byteorder
654 != target->header_byteorder))
655 continue;
657 back = (const struct elf_backend_data *) (*target_ptr)->backend_data;
658 if (back->elf_osabi == i_ehdrp->e_ident[EI_OSABI]
659 && (back->elf_machine_code == i_ehdrp->e_machine
660 || (back->elf_machine_alt1 != 0
661 && back->elf_machine_alt1 == i_ehdrp->e_machine)
662 || (back->elf_machine_alt2 != 0
663 && back->elf_machine_alt2 == i_ehdrp->e_machine)))
665 /* target_ptr is an ELF backend which matches this
666 object file, so reject the ELFOSABI_NONE ELF target. */
667 goto got_wrong_format_error;
672 if (i_ehdrp->e_shoff != 0)
674 bfd_signed_vma where = i_ehdrp->e_shoff;
676 if (where != (file_ptr) where)
677 goto got_wrong_format_error;
679 /* Seek to the section header table in the file. */
680 if (bfd_seek (abfd, (file_ptr) where, SEEK_SET) != 0)
681 goto got_no_match;
683 /* Read the first section header at index 0, and convert to internal
684 form. */
685 if (bfd_bread (&x_shdr, sizeof x_shdr, abfd) != sizeof (x_shdr))
686 goto got_no_match;
687 elf_swap_shdr_in (abfd, &x_shdr, &i_shdr);
689 /* If the section count is zero, the actual count is in the first
690 section header. */
691 if (i_ehdrp->e_shnum == SHN_UNDEF)
693 i_ehdrp->e_shnum = i_shdr.sh_size;
694 if (i_ehdrp->e_shnum != i_shdr.sh_size
695 || i_ehdrp->e_shnum == 0)
696 goto got_wrong_format_error;
699 /* And similarly for the string table index. */
700 if (i_ehdrp->e_shstrndx == SHN_XINDEX)
702 i_ehdrp->e_shstrndx = i_shdr.sh_link;
703 if (i_ehdrp->e_shstrndx != i_shdr.sh_link)
704 goto got_wrong_format_error;
707 /* Sanity check that we can read all of the section headers.
708 It ought to be good enough to just read the last one. */
709 if (i_ehdrp->e_shnum != 1)
711 /* Check that we don't have a totally silly number of sections. */
712 if (i_ehdrp->e_shnum > (unsigned int) -1 / sizeof (x_shdr)
713 || i_ehdrp->e_shnum > (unsigned int) -1 / sizeof (i_shdr))
714 goto got_wrong_format_error;
716 where += (i_ehdrp->e_shnum - 1) * sizeof (x_shdr);
717 if (where != (file_ptr) where)
718 goto got_wrong_format_error;
719 if ((bfd_size_type) where <= i_ehdrp->e_shoff)
720 goto got_wrong_format_error;
722 if (bfd_seek (abfd, (file_ptr) where, SEEK_SET) != 0)
723 goto got_no_match;
724 if (bfd_bread (&x_shdr, sizeof x_shdr, abfd) != sizeof (x_shdr))
725 goto got_no_match;
727 /* Back to where we were. */
728 where = i_ehdrp->e_shoff + sizeof (x_shdr);
729 if (bfd_seek (abfd, (file_ptr) where, SEEK_SET) != 0)
730 goto got_no_match;
734 /* Allocate space for a copy of the section header table in
735 internal form. */
736 if (i_ehdrp->e_shnum != 0)
738 Elf_Internal_Shdr *shdrp;
739 unsigned int num_sec;
741 amt = sizeof (*i_shdrp) * i_ehdrp->e_shnum;
742 i_shdrp = bfd_alloc (abfd, amt);
743 if (!i_shdrp)
744 goto got_no_match;
745 num_sec = i_ehdrp->e_shnum;
746 if (num_sec > SHN_LORESERVE)
747 num_sec += SHN_HIRESERVE + 1 - SHN_LORESERVE;
748 elf_numsections (abfd) = num_sec;
749 amt = sizeof (i_shdrp) * num_sec;
750 elf_elfsections (abfd) = bfd_alloc (abfd, amt);
751 if (!elf_elfsections (abfd))
752 goto got_no_match;
754 memcpy (i_shdrp, &i_shdr, sizeof (*i_shdrp));
755 shdrp = i_shdrp;
756 shindex = 0;
757 if (num_sec > SHN_LORESERVE)
759 for ( ; shindex < SHN_LORESERVE; shindex++)
760 elf_elfsections (abfd)[shindex] = shdrp++;
761 for ( ; shindex < SHN_HIRESERVE + 1; shindex++)
762 elf_elfsections (abfd)[shindex] = i_shdrp;
764 for ( ; shindex < num_sec; shindex++)
765 elf_elfsections (abfd)[shindex] = shdrp++;
767 /* Read in the rest of the section header table and convert it
768 to internal form. */
769 for (shindex = 1; shindex < i_ehdrp->e_shnum; shindex++)
771 if (bfd_bread (&x_shdr, sizeof x_shdr, abfd) != sizeof (x_shdr))
772 goto got_no_match;
773 elf_swap_shdr_in (abfd, &x_shdr, i_shdrp + shindex);
775 /* Sanity check sh_link and sh_info. */
776 if (! valid_section_index_p (i_shdrp[shindex].sh_link, num_sec))
777 goto got_wrong_format_error;
779 if (((i_shdrp[shindex].sh_flags & SHF_INFO_LINK)
780 || i_shdrp[shindex].sh_type == SHT_RELA
781 || i_shdrp[shindex].sh_type == SHT_REL)
782 && ! valid_section_index_p (i_shdrp[shindex].sh_info, num_sec))
783 goto got_wrong_format_error;
785 /* If the section is loaded, but not page aligned, clear
786 D_PAGED. */
787 if (i_shdrp[shindex].sh_size != 0
788 && (i_shdrp[shindex].sh_flags & SHF_ALLOC) != 0
789 && i_shdrp[shindex].sh_type != SHT_NOBITS
790 && (((i_shdrp[shindex].sh_addr - i_shdrp[shindex].sh_offset)
791 % ebd->minpagesize)
792 != 0))
793 abfd->flags &= ~D_PAGED;
797 /* A further sanity check. */
798 if (i_ehdrp->e_shnum != 0)
800 if (! valid_section_index_p (i_ehdrp->e_shstrndx, elf_numsections (abfd)))
802 /* PR 2257:
803 We used to just goto got_wrong_format_error here
804 but there are binaries in existance for which this test
805 will prevent the binutils from working with them at all.
806 So we are kind, and reset the string index value to 0
807 so that at least some processing can be done. */
808 i_ehdrp->e_shstrndx = SHN_UNDEF;
809 _bfd_error_handler (_("warning: %s has a corrupt string table index - ignoring"), abfd->filename);
812 else if (i_ehdrp->e_shstrndx != SHN_UNDEF)
813 goto got_wrong_format_error;
815 /* Read in the program headers. */
816 if (i_ehdrp->e_phnum == 0)
817 elf_tdata (abfd)->phdr = NULL;
818 else
820 Elf_Internal_Phdr *i_phdr;
821 unsigned int i;
823 amt = i_ehdrp->e_phnum * sizeof (Elf_Internal_Phdr);
824 elf_tdata (abfd)->phdr = bfd_alloc (abfd, amt);
825 if (elf_tdata (abfd)->phdr == NULL)
826 goto got_no_match;
827 if (bfd_seek (abfd, (file_ptr) i_ehdrp->e_phoff, SEEK_SET) != 0)
828 goto got_no_match;
829 i_phdr = elf_tdata (abfd)->phdr;
830 for (i = 0; i < i_ehdrp->e_phnum; i++, i_phdr++)
832 Elf_External_Phdr x_phdr;
834 if (bfd_bread (&x_phdr, sizeof x_phdr, abfd) != sizeof x_phdr)
835 goto got_no_match;
836 elf_swap_phdr_in (abfd, &x_phdr, i_phdr);
840 if (i_ehdrp->e_shstrndx != 0 && i_ehdrp->e_shoff != 0)
842 unsigned int num_sec;
844 /* Once all of the section headers have been read and converted, we
845 can start processing them. Note that the first section header is
846 a dummy placeholder entry, so we ignore it. */
847 num_sec = elf_numsections (abfd);
848 for (shindex = 1; shindex < num_sec; shindex++)
850 if (! bfd_section_from_shdr (abfd, shindex))
851 goto got_no_match;
852 if (shindex == SHN_LORESERVE - 1)
853 shindex += SHN_HIRESERVE + 1 - SHN_LORESERVE;
856 /* Set up ELF sections for SHF_GROUP and SHF_LINK_ORDER. */
857 if (! _bfd_elf_setup_sections (abfd))
858 goto got_wrong_format_error;
861 /* Let the backend double check the format and override global
862 information. */
863 if (ebd->elf_backend_object_p)
865 if (! (*ebd->elf_backend_object_p) (abfd))
866 goto got_wrong_format_error;
869 /* Remember the entry point specified in the ELF file header. */
870 bfd_set_start_address (abfd, i_ehdrp->e_entry);
872 /* If we have created any reloc sections that are associated with
873 debugging sections, mark the reloc sections as debugging as well. */
874 for (s = abfd->sections; s != NULL; s = s->next)
876 if ((elf_section_data (s)->this_hdr.sh_type == SHT_REL
877 || elf_section_data (s)->this_hdr.sh_type == SHT_RELA)
878 && elf_section_data (s)->this_hdr.sh_info > 0)
880 unsigned long targ_index;
881 asection *targ_sec;
883 targ_index = elf_section_data (s)->this_hdr.sh_info;
884 targ_sec = bfd_section_from_elf_index (abfd, targ_index);
885 if (targ_sec != NULL
886 && (targ_sec->flags & SEC_DEBUGGING) != 0)
887 s->flags |= SEC_DEBUGGING;
891 bfd_preserve_finish (abfd, &preserve);
892 return target;
894 got_wrong_format_error:
895 /* There is way too much undoing of half-known state here. The caller,
896 bfd_check_format_matches, really shouldn't iterate on live bfd's to
897 check match/no-match like it does. We have to rely on that a call to
898 bfd_default_set_arch_mach with the previously known mach, undoes what
899 was done by the first bfd_default_set_arch_mach (with mach 0) here.
900 For this to work, only elf-data and the mach may be changed by the
901 target-specific elf_backend_object_p function. Note that saving the
902 whole bfd here and restoring it would be even worse; the first thing
903 you notice is that the cached bfd file position gets out of sync. */
904 bfd_set_error (bfd_error_wrong_format);
906 got_no_match:
907 if (preserve.marker != NULL)
908 bfd_preserve_restore (abfd, &preserve);
909 return NULL;
912 /* ELF .o/exec file writing */
914 /* Write out the relocs. */
916 void
917 elf_write_relocs (bfd *abfd, asection *sec, void *data)
919 bfd_boolean *failedp = data;
920 Elf_Internal_Shdr *rela_hdr;
921 bfd_vma addr_offset;
922 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
923 size_t extsize;
924 bfd_byte *dst_rela;
925 unsigned int idx;
926 asymbol *last_sym;
927 int last_sym_idx;
929 /* If we have already failed, don't do anything. */
930 if (*failedp)
931 return;
933 if ((sec->flags & SEC_RELOC) == 0)
934 return;
936 /* The linker backend writes the relocs out itself, and sets the
937 reloc_count field to zero to inhibit writing them here. Also,
938 sometimes the SEC_RELOC flag gets set even when there aren't any
939 relocs. */
940 if (sec->reloc_count == 0)
941 return;
943 /* If we have opened an existing file for update, reloc_count may be
944 set even though we are not linking. In that case we have nothing
945 to do. */
946 if (sec->orelocation == NULL)
947 return;
949 rela_hdr = &elf_section_data (sec)->rel_hdr;
951 rela_hdr->sh_size = rela_hdr->sh_entsize * sec->reloc_count;
952 rela_hdr->contents = bfd_alloc (abfd, rela_hdr->sh_size);
953 if (rela_hdr->contents == NULL)
955 *failedp = TRUE;
956 return;
959 /* Figure out whether the relocations are RELA or REL relocations. */
960 if (rela_hdr->sh_type == SHT_RELA)
962 swap_out = elf_swap_reloca_out;
963 extsize = sizeof (Elf_External_Rela);
965 else if (rela_hdr->sh_type == SHT_REL)
967 swap_out = elf_swap_reloc_out;
968 extsize = sizeof (Elf_External_Rel);
970 else
971 /* Every relocation section should be either an SHT_RELA or an
972 SHT_REL section. */
973 abort ();
975 /* The address of an ELF reloc is section relative for an object
976 file, and absolute for an executable file or shared library.
977 The address of a BFD reloc is always section relative. */
978 addr_offset = 0;
979 if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
980 addr_offset = sec->vma;
982 /* orelocation has the data, reloc_count has the count... */
983 last_sym = 0;
984 last_sym_idx = 0;
985 dst_rela = rela_hdr->contents;
987 for (idx = 0; idx < sec->reloc_count; idx++, dst_rela += extsize)
989 Elf_Internal_Rela src_rela;
990 arelent *ptr;
991 asymbol *sym;
992 int n;
994 ptr = sec->orelocation[idx];
995 sym = *ptr->sym_ptr_ptr;
996 if (sym == last_sym)
997 n = last_sym_idx;
998 else if (bfd_is_abs_section (sym->section) && sym->value == 0)
999 n = STN_UNDEF;
1000 else
1002 last_sym = sym;
1003 n = _bfd_elf_symbol_from_bfd_symbol (abfd, &sym);
1004 if (n < 0)
1006 *failedp = TRUE;
1007 return;
1009 last_sym_idx = n;
1012 if ((*ptr->sym_ptr_ptr)->the_bfd != NULL
1013 && (*ptr->sym_ptr_ptr)->the_bfd->xvec != abfd->xvec
1014 && ! _bfd_elf_validate_reloc (abfd, ptr))
1016 *failedp = TRUE;
1017 return;
1020 src_rela.r_offset = ptr->address + addr_offset;
1021 src_rela.r_info = ELF_R_INFO (n, ptr->howto->type);
1022 src_rela.r_addend = ptr->addend;
1023 (*swap_out) (abfd, &src_rela, dst_rela);
1027 /* Write out the program headers. */
1030 elf_write_out_phdrs (bfd *abfd,
1031 const Elf_Internal_Phdr *phdr,
1032 unsigned int count)
1034 while (count--)
1036 Elf_External_Phdr extphdr;
1037 elf_swap_phdr_out (abfd, phdr, &extphdr);
1038 if (bfd_bwrite (&extphdr, sizeof (Elf_External_Phdr), abfd)
1039 != sizeof (Elf_External_Phdr))
1040 return -1;
1041 phdr++;
1043 return 0;
1046 /* Write out the section headers and the ELF file header. */
1048 bfd_boolean
1049 elf_write_shdrs_and_ehdr (bfd *abfd)
1051 Elf_External_Ehdr x_ehdr; /* Elf file header, external form */
1052 Elf_Internal_Ehdr *i_ehdrp; /* Elf file header, internal form */
1053 Elf_External_Shdr *x_shdrp; /* Section header table, external form */
1054 Elf_Internal_Shdr **i_shdrp; /* Section header table, internal form */
1055 unsigned int count;
1056 bfd_size_type amt;
1058 i_ehdrp = elf_elfheader (abfd);
1059 i_shdrp = elf_elfsections (abfd);
1061 /* swap the header before spitting it out... */
1063 #if DEBUG & 1
1064 elf_debug_file (i_ehdrp);
1065 #endif
1066 elf_swap_ehdr_out (abfd, i_ehdrp, &x_ehdr);
1067 amt = sizeof (x_ehdr);
1068 if (bfd_seek (abfd, (file_ptr) 0, SEEK_SET) != 0
1069 || bfd_bwrite (&x_ehdr, amt, abfd) != amt)
1070 return FALSE;
1072 /* Some fields in the first section header handle overflow of ehdr
1073 fields. */
1074 if (i_ehdrp->e_shnum >= SHN_LORESERVE)
1075 i_shdrp[0]->sh_size = i_ehdrp->e_shnum;
1076 if (i_ehdrp->e_shstrndx >= SHN_LORESERVE)
1077 i_shdrp[0]->sh_link = i_ehdrp->e_shstrndx;
1079 /* at this point we've concocted all the ELF sections... */
1080 amt = i_ehdrp->e_shnum;
1081 amt *= sizeof (*x_shdrp);
1082 x_shdrp = bfd_alloc (abfd, amt);
1083 if (!x_shdrp)
1084 return FALSE;
1086 for (count = 0; count < i_ehdrp->e_shnum; i_shdrp++, count++)
1088 #if DEBUG & 2
1089 elf_debug_section (count, *i_shdrp);
1090 #endif
1091 elf_swap_shdr_out (abfd, *i_shdrp, x_shdrp + count);
1093 if (count == SHN_LORESERVE - 1)
1094 i_shdrp += SHN_HIRESERVE + 1 - SHN_LORESERVE;
1096 if (bfd_seek (abfd, (file_ptr) i_ehdrp->e_shoff, SEEK_SET) != 0
1097 || bfd_bwrite (x_shdrp, amt, abfd) != amt)
1098 return FALSE;
1100 /* need to dump the string table too... */
1102 return TRUE;
1105 long
1106 elf_slurp_symbol_table (bfd *abfd, asymbol **symptrs, bfd_boolean dynamic)
1108 Elf_Internal_Shdr *hdr;
1109 Elf_Internal_Shdr *verhdr;
1110 unsigned long symcount; /* Number of external ELF symbols */
1111 elf_symbol_type *sym; /* Pointer to current bfd symbol */
1112 elf_symbol_type *symbase; /* Buffer for generated bfd symbols */
1113 Elf_Internal_Sym *isym;
1114 Elf_Internal_Sym *isymend;
1115 Elf_Internal_Sym *isymbuf = NULL;
1116 Elf_External_Versym *xver;
1117 Elf_External_Versym *xverbuf = NULL;
1118 const struct elf_backend_data *ebd;
1119 bfd_size_type amt;
1121 /* Read each raw ELF symbol, converting from external ELF form to
1122 internal ELF form, and then using the information to create a
1123 canonical bfd symbol table entry.
1125 Note that we allocate the initial bfd canonical symbol buffer
1126 based on a one-to-one mapping of the ELF symbols to canonical
1127 symbols. We actually use all the ELF symbols, so there will be no
1128 space left over at the end. When we have all the symbols, we
1129 build the caller's pointer vector. */
1131 if (! dynamic)
1133 hdr = &elf_tdata (abfd)->symtab_hdr;
1134 verhdr = NULL;
1136 else
1138 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
1139 if (elf_dynversym (abfd) == 0)
1140 verhdr = NULL;
1141 else
1142 verhdr = &elf_tdata (abfd)->dynversym_hdr;
1143 if ((elf_tdata (abfd)->dynverdef_section != 0
1144 && elf_tdata (abfd)->verdef == NULL)
1145 || (elf_tdata (abfd)->dynverref_section != 0
1146 && elf_tdata (abfd)->verref == NULL))
1148 if (!_bfd_elf_slurp_version_tables (abfd, FALSE))
1149 return -1;
1153 ebd = get_elf_backend_data (abfd);
1154 symcount = hdr->sh_size / sizeof (Elf_External_Sym);
1155 if (symcount == 0)
1156 sym = symbase = NULL;
1157 else
1159 isymbuf = bfd_elf_get_elf_syms (abfd, hdr, symcount, 0,
1160 NULL, NULL, NULL);
1161 if (isymbuf == NULL)
1162 return -1;
1164 amt = symcount;
1165 amt *= sizeof (elf_symbol_type);
1166 symbase = bfd_zalloc (abfd, amt);
1167 if (symbase == (elf_symbol_type *) NULL)
1168 goto error_return;
1170 /* Read the raw ELF version symbol information. */
1171 if (verhdr != NULL
1172 && verhdr->sh_size / sizeof (Elf_External_Versym) != symcount)
1174 (*_bfd_error_handler)
1175 (_("%s: version count (%ld) does not match symbol count (%ld)"),
1176 abfd->filename,
1177 (long) (verhdr->sh_size / sizeof (Elf_External_Versym)),
1178 symcount);
1180 /* Slurp in the symbols without the version information,
1181 since that is more helpful than just quitting. */
1182 verhdr = NULL;
1185 if (verhdr != NULL)
1187 if (bfd_seek (abfd, verhdr->sh_offset, SEEK_SET) != 0)
1188 goto error_return;
1190 xverbuf = bfd_malloc (verhdr->sh_size);
1191 if (xverbuf == NULL && verhdr->sh_size != 0)
1192 goto error_return;
1194 if (bfd_bread (xverbuf, verhdr->sh_size, abfd) != verhdr->sh_size)
1195 goto error_return;
1198 /* Skip first symbol, which is a null dummy. */
1199 xver = xverbuf;
1200 if (xver != NULL)
1201 ++xver;
1202 isymend = isymbuf + symcount;
1203 for (isym = isymbuf + 1, sym = symbase; isym < isymend; isym++, sym++)
1205 memcpy (&sym->internal_elf_sym, isym, sizeof (Elf_Internal_Sym));
1206 sym->symbol.the_bfd = abfd;
1208 sym->symbol.name = bfd_elf_sym_name (abfd, hdr, isym, NULL);
1210 sym->symbol.value = isym->st_value;
1212 if (isym->st_shndx == SHN_UNDEF)
1214 sym->symbol.section = bfd_und_section_ptr;
1216 else if (isym->st_shndx < SHN_LORESERVE
1217 || isym->st_shndx > SHN_HIRESERVE)
1219 sym->symbol.section = bfd_section_from_elf_index (abfd,
1220 isym->st_shndx);
1221 if (sym->symbol.section == NULL)
1223 /* This symbol is in a section for which we did not
1224 create a BFD section. Just use bfd_abs_section,
1225 although it is wrong. FIXME. */
1226 sym->symbol.section = bfd_abs_section_ptr;
1229 else if (isym->st_shndx == SHN_ABS)
1231 sym->symbol.section = bfd_abs_section_ptr;
1233 else if (isym->st_shndx == SHN_COMMON)
1235 sym->symbol.section = bfd_com_section_ptr;
1236 /* Elf puts the alignment into the `value' field, and
1237 the size into the `size' field. BFD wants to see the
1238 size in the value field, and doesn't care (at the
1239 moment) about the alignment. */
1240 sym->symbol.value = isym->st_size;
1242 else
1243 sym->symbol.section = bfd_abs_section_ptr;
1245 /* If this is a relocatable file, then the symbol value is
1246 already section relative. */
1247 if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
1248 sym->symbol.value -= sym->symbol.section->vma;
1250 switch (ELF_ST_BIND (isym->st_info))
1252 case STB_LOCAL:
1253 sym->symbol.flags |= BSF_LOCAL;
1254 break;
1255 case STB_GLOBAL:
1256 if (isym->st_shndx != SHN_UNDEF && isym->st_shndx != SHN_COMMON)
1257 sym->symbol.flags |= BSF_GLOBAL;
1258 break;
1259 case STB_WEAK:
1260 sym->symbol.flags |= BSF_WEAK;
1261 break;
1264 switch (ELF_ST_TYPE (isym->st_info))
1266 case STT_SECTION:
1267 sym->symbol.flags |= BSF_SECTION_SYM | BSF_DEBUGGING;
1268 break;
1269 case STT_FILE:
1270 sym->symbol.flags |= BSF_FILE | BSF_DEBUGGING;
1271 break;
1272 case STT_FUNC:
1273 sym->symbol.flags |= BSF_FUNCTION;
1274 break;
1275 case STT_OBJECT:
1276 sym->symbol.flags |= BSF_OBJECT;
1277 break;
1278 case STT_TLS:
1279 sym->symbol.flags |= BSF_THREAD_LOCAL;
1280 break;
1281 case STT_RELC:
1282 sym->symbol.flags |= BSF_RELC;
1283 break;
1284 case STT_SRELC:
1285 sym->symbol.flags |= BSF_SRELC;
1286 break;
1289 if (dynamic)
1290 sym->symbol.flags |= BSF_DYNAMIC;
1292 if (xver != NULL)
1294 Elf_Internal_Versym iversym;
1296 _bfd_elf_swap_versym_in (abfd, xver, &iversym);
1297 sym->version = iversym.vs_vers;
1298 xver++;
1301 /* Do some backend-specific processing on this symbol. */
1302 if (ebd->elf_backend_symbol_processing)
1303 (*ebd->elf_backend_symbol_processing) (abfd, &sym->symbol);
1307 /* Do some backend-specific processing on this symbol table. */
1308 if (ebd->elf_backend_symbol_table_processing)
1309 (*ebd->elf_backend_symbol_table_processing) (abfd, symbase, symcount);
1311 /* We rely on the zalloc to clear out the final symbol entry. */
1313 symcount = sym - symbase;
1315 /* Fill in the user's symbol pointer vector if needed. */
1316 if (symptrs)
1318 long l = symcount;
1320 sym = symbase;
1321 while (l-- > 0)
1323 *symptrs++ = &sym->symbol;
1324 sym++;
1326 *symptrs = 0; /* Final null pointer */
1329 if (xverbuf != NULL)
1330 free (xverbuf);
1331 if (isymbuf != NULL && hdr->contents != (unsigned char *) isymbuf)
1332 free (isymbuf);
1333 return symcount;
1335 error_return:
1336 if (xverbuf != NULL)
1337 free (xverbuf);
1338 if (isymbuf != NULL && hdr->contents != (unsigned char *) isymbuf)
1339 free (isymbuf);
1340 return -1;
1343 /* Read relocations for ASECT from REL_HDR. There are RELOC_COUNT of
1344 them. */
1346 static bfd_boolean
1347 elf_slurp_reloc_table_from_section (bfd *abfd,
1348 asection *asect,
1349 Elf_Internal_Shdr *rel_hdr,
1350 bfd_size_type reloc_count,
1351 arelent *relents,
1352 asymbol **symbols,
1353 bfd_boolean dynamic)
1355 const struct elf_backend_data * const ebd = get_elf_backend_data (abfd);
1356 void *allocated = NULL;
1357 bfd_byte *native_relocs;
1358 arelent *relent;
1359 unsigned int i;
1360 int entsize;
1361 unsigned int symcount;
1363 allocated = bfd_malloc (rel_hdr->sh_size);
1364 if (allocated == NULL)
1365 goto error_return;
1367 if (bfd_seek (abfd, rel_hdr->sh_offset, SEEK_SET) != 0
1368 || (bfd_bread (allocated, rel_hdr->sh_size, abfd)
1369 != rel_hdr->sh_size))
1370 goto error_return;
1372 native_relocs = allocated;
1374 entsize = rel_hdr->sh_entsize;
1375 BFD_ASSERT (entsize == sizeof (Elf_External_Rel)
1376 || entsize == sizeof (Elf_External_Rela));
1378 if (dynamic)
1379 symcount = bfd_get_dynamic_symcount (abfd);
1380 else
1381 symcount = bfd_get_symcount (abfd);
1383 for (i = 0, relent = relents;
1384 i < reloc_count;
1385 i++, relent++, native_relocs += entsize)
1387 Elf_Internal_Rela rela;
1389 if (entsize == sizeof (Elf_External_Rela))
1390 elf_swap_reloca_in (abfd, native_relocs, &rela);
1391 else
1392 elf_swap_reloc_in (abfd, native_relocs, &rela);
1394 /* The address of an ELF reloc is section relative for an object
1395 file, and absolute for an executable file or shared library.
1396 The address of a normal BFD reloc is always section relative,
1397 and the address of a dynamic reloc is absolute.. */
1398 if ((abfd->flags & (EXEC_P | DYNAMIC)) == 0 || dynamic)
1399 relent->address = rela.r_offset;
1400 else
1401 relent->address = rela.r_offset - asect->vma;
1403 if (ELF_R_SYM (rela.r_info) == 0)
1404 relent->sym_ptr_ptr = bfd_abs_section_ptr->symbol_ptr_ptr;
1405 else if (ELF_R_SYM (rela.r_info) > symcount)
1407 (*_bfd_error_handler)
1408 (_("%s(%s): relocation %d has invalid symbol index %ld"),
1409 abfd->filename, asect->name, i, ELF_R_SYM (rela.r_info));
1410 relent->sym_ptr_ptr = bfd_abs_section.symbol_ptr_ptr;
1412 else
1414 asymbol **ps;
1416 ps = symbols + ELF_R_SYM (rela.r_info) - 1;
1418 relent->sym_ptr_ptr = ps;
1421 relent->addend = rela.r_addend;
1423 if ((entsize == sizeof (Elf_External_Rela)
1424 && ebd->elf_info_to_howto != NULL)
1425 || ebd->elf_info_to_howto_rel == NULL)
1426 (*ebd->elf_info_to_howto) (abfd, relent, &rela);
1427 else
1428 (*ebd->elf_info_to_howto_rel) (abfd, relent, &rela);
1431 if (allocated != NULL)
1432 free (allocated);
1434 return TRUE;
1436 error_return:
1437 if (allocated != NULL)
1438 free (allocated);
1439 return FALSE;
1442 /* Read in and swap the external relocs. */
1444 bfd_boolean
1445 elf_slurp_reloc_table (bfd *abfd,
1446 asection *asect,
1447 asymbol **symbols,
1448 bfd_boolean dynamic)
1450 struct bfd_elf_section_data * const d = elf_section_data (asect);
1451 Elf_Internal_Shdr *rel_hdr;
1452 Elf_Internal_Shdr *rel_hdr2;
1453 bfd_size_type reloc_count;
1454 bfd_size_type reloc_count2;
1455 arelent *relents;
1456 bfd_size_type amt;
1458 if (asect->relocation != NULL)
1459 return TRUE;
1461 if (! dynamic)
1463 if ((asect->flags & SEC_RELOC) == 0
1464 || asect->reloc_count == 0)
1465 return TRUE;
1467 rel_hdr = &d->rel_hdr;
1468 reloc_count = NUM_SHDR_ENTRIES (rel_hdr);
1469 rel_hdr2 = d->rel_hdr2;
1470 reloc_count2 = (rel_hdr2 ? NUM_SHDR_ENTRIES (rel_hdr2) : 0);
1472 BFD_ASSERT (asect->reloc_count == reloc_count + reloc_count2);
1473 BFD_ASSERT (asect->rel_filepos == rel_hdr->sh_offset
1474 || (rel_hdr2 && asect->rel_filepos == rel_hdr2->sh_offset));
1477 else
1479 /* Note that ASECT->RELOC_COUNT tends not to be accurate in this
1480 case because relocations against this section may use the
1481 dynamic symbol table, and in that case bfd_section_from_shdr
1482 in elf.c does not update the RELOC_COUNT. */
1483 if (asect->size == 0)
1484 return TRUE;
1486 rel_hdr = &d->this_hdr;
1487 reloc_count = NUM_SHDR_ENTRIES (rel_hdr);
1488 rel_hdr2 = NULL;
1489 reloc_count2 = 0;
1492 amt = (reloc_count + reloc_count2) * sizeof (arelent);
1493 relents = bfd_alloc (abfd, amt);
1494 if (relents == NULL)
1495 return FALSE;
1497 if (!elf_slurp_reloc_table_from_section (abfd, asect,
1498 rel_hdr, reloc_count,
1499 relents,
1500 symbols, dynamic))
1501 return FALSE;
1503 if (rel_hdr2
1504 && !elf_slurp_reloc_table_from_section (abfd, asect,
1505 rel_hdr2, reloc_count2,
1506 relents + reloc_count,
1507 symbols, dynamic))
1508 return FALSE;
1510 asect->relocation = relents;
1511 return TRUE;
1514 #if DEBUG & 2
1515 static void
1516 elf_debug_section (int num, Elf_Internal_Shdr *hdr)
1518 fprintf (stderr, "\nSection#%d '%s' 0x%.8lx\n", num,
1519 hdr->bfd_section != NULL ? hdr->bfd_section->name : "",
1520 (long) hdr);
1521 fprintf (stderr,
1522 "sh_name = %ld\tsh_type = %ld\tsh_flags = %ld\n",
1523 (long) hdr->sh_name,
1524 (long) hdr->sh_type,
1525 (long) hdr->sh_flags);
1526 fprintf (stderr,
1527 "sh_addr = %ld\tsh_offset = %ld\tsh_size = %ld\n",
1528 (long) hdr->sh_addr,
1529 (long) hdr->sh_offset,
1530 (long) hdr->sh_size);
1531 fprintf (stderr,
1532 "sh_link = %ld\tsh_info = %ld\tsh_addralign = %ld\n",
1533 (long) hdr->sh_link,
1534 (long) hdr->sh_info,
1535 (long) hdr->sh_addralign);
1536 fprintf (stderr, "sh_entsize = %ld\n",
1537 (long) hdr->sh_entsize);
1538 fflush (stderr);
1540 #endif
1542 #if DEBUG & 1
1543 static void
1544 elf_debug_file (Elf_Internal_Ehdr *ehdrp)
1546 fprintf (stderr, "e_entry = 0x%.8lx\n", (long) ehdrp->e_entry);
1547 fprintf (stderr, "e_phoff = %ld\n", (long) ehdrp->e_phoff);
1548 fprintf (stderr, "e_phnum = %ld\n", (long) ehdrp->e_phnum);
1549 fprintf (stderr, "e_phentsize = %ld\n", (long) ehdrp->e_phentsize);
1550 fprintf (stderr, "e_shoff = %ld\n", (long) ehdrp->e_shoff);
1551 fprintf (stderr, "e_shnum = %ld\n", (long) ehdrp->e_shnum);
1552 fprintf (stderr, "e_shentsize = %ld\n", (long) ehdrp->e_shentsize);
1554 #endif
1556 /* Create a new BFD as if by bfd_openr. Rather than opening a file,
1557 reconstruct an ELF file by reading the segments out of remote memory
1558 based on the ELF file header at EHDR_VMA and the ELF program headers it
1559 points to. If not null, *LOADBASEP is filled in with the difference
1560 between the VMAs from which the segments were read, and the VMAs the
1561 file headers (and hence BFD's idea of each section's VMA) put them at.
1563 The function TARGET_READ_MEMORY is called to copy LEN bytes from the
1564 remote memory at target address VMA into the local buffer at MYADDR; it
1565 should return zero on success or an `errno' code on failure. TEMPL must
1566 be a BFD for a target with the word size and byte order found in the
1567 remote memory. */
1569 bfd *
1570 NAME(_bfd_elf,bfd_from_remote_memory)
1571 (bfd *templ,
1572 bfd_vma ehdr_vma,
1573 bfd_vma *loadbasep,
1574 int (*target_read_memory) (bfd_vma, bfd_byte *, int))
1576 Elf_External_Ehdr x_ehdr; /* Elf file header, external form */
1577 Elf_Internal_Ehdr i_ehdr; /* Elf file header, internal form */
1578 Elf_External_Phdr *x_phdrs;
1579 Elf_Internal_Phdr *i_phdrs, *last_phdr;
1580 bfd *nbfd;
1581 struct bfd_in_memory *bim;
1582 int contents_size;
1583 bfd_byte *contents;
1584 int err;
1585 unsigned int i;
1586 bfd_vma loadbase;
1588 /* Read in the ELF header in external format. */
1589 err = target_read_memory (ehdr_vma, (bfd_byte *) &x_ehdr, sizeof x_ehdr);
1590 if (err)
1592 bfd_set_error (bfd_error_system_call);
1593 errno = err;
1594 return NULL;
1597 /* Now check to see if we have a valid ELF file, and one that BFD can
1598 make use of. The magic number must match, the address size ('class')
1599 and byte-swapping must match our XVEC entry. */
1601 if (! elf_file_p (&x_ehdr)
1602 || x_ehdr.e_ident[EI_VERSION] != EV_CURRENT
1603 || x_ehdr.e_ident[EI_CLASS] != ELFCLASS)
1605 bfd_set_error (bfd_error_wrong_format);
1606 return NULL;
1609 /* Check that file's byte order matches xvec's */
1610 switch (x_ehdr.e_ident[EI_DATA])
1612 case ELFDATA2MSB: /* Big-endian */
1613 if (! bfd_header_big_endian (templ))
1615 bfd_set_error (bfd_error_wrong_format);
1616 return NULL;
1618 break;
1619 case ELFDATA2LSB: /* Little-endian */
1620 if (! bfd_header_little_endian (templ))
1622 bfd_set_error (bfd_error_wrong_format);
1623 return NULL;
1625 break;
1626 case ELFDATANONE: /* No data encoding specified */
1627 default: /* Unknown data encoding specified */
1628 bfd_set_error (bfd_error_wrong_format);
1629 return NULL;
1632 elf_swap_ehdr_in (templ, &x_ehdr, &i_ehdr);
1634 /* The file header tells where to find the program headers.
1635 These are what we use to actually choose what to read. */
1637 if (i_ehdr.e_phentsize != sizeof (Elf_External_Phdr) || i_ehdr.e_phnum == 0)
1639 bfd_set_error (bfd_error_wrong_format);
1640 return NULL;
1643 x_phdrs = bfd_malloc (i_ehdr.e_phnum * (sizeof *x_phdrs + sizeof *i_phdrs));
1644 if (x_phdrs == NULL)
1646 bfd_set_error (bfd_error_no_memory);
1647 return NULL;
1649 err = target_read_memory (ehdr_vma + i_ehdr.e_phoff, (bfd_byte *) x_phdrs,
1650 i_ehdr.e_phnum * sizeof x_phdrs[0]);
1651 if (err)
1653 free (x_phdrs);
1654 bfd_set_error (bfd_error_system_call);
1655 errno = err;
1656 return NULL;
1658 i_phdrs = (Elf_Internal_Phdr *) &x_phdrs[i_ehdr.e_phnum];
1660 contents_size = 0;
1661 last_phdr = NULL;
1662 loadbase = ehdr_vma;
1663 for (i = 0; i < i_ehdr.e_phnum; ++i)
1665 elf_swap_phdr_in (templ, &x_phdrs[i], &i_phdrs[i]);
1666 /* IA-64 vDSO may have two mappings for one segment, where one mapping
1667 is executable only, and one is read only. We must not use the
1668 executable one. */
1669 if (i_phdrs[i].p_type == PT_LOAD && (i_phdrs[i].p_flags & PF_R))
1671 bfd_vma segment_end;
1672 segment_end = (i_phdrs[i].p_offset + i_phdrs[i].p_filesz
1673 + i_phdrs[i].p_align - 1) & -i_phdrs[i].p_align;
1674 if (segment_end > (bfd_vma) contents_size)
1675 contents_size = segment_end;
1677 if ((i_phdrs[i].p_offset & -i_phdrs[i].p_align) == 0)
1678 loadbase = ehdr_vma - (i_phdrs[i].p_vaddr & -i_phdrs[i].p_align);
1680 last_phdr = &i_phdrs[i];
1683 if (last_phdr == NULL)
1685 /* There were no PT_LOAD segments, so we don't have anything to read. */
1686 free (x_phdrs);
1687 bfd_set_error (bfd_error_wrong_format);
1688 return NULL;
1691 /* Trim the last segment so we don't bother with zeros in the last page
1692 that are off the end of the file. However, if the extra bit in that
1693 page includes the section headers, keep them. */
1694 if ((bfd_vma) contents_size > last_phdr->p_offset + last_phdr->p_filesz
1695 && (bfd_vma) contents_size >= (i_ehdr.e_shoff
1696 + i_ehdr.e_shnum * i_ehdr.e_shentsize))
1698 contents_size = last_phdr->p_offset + last_phdr->p_filesz;
1699 if ((bfd_vma) contents_size < (i_ehdr.e_shoff
1700 + i_ehdr.e_shnum * i_ehdr.e_shentsize))
1701 contents_size = i_ehdr.e_shoff + i_ehdr.e_shnum * i_ehdr.e_shentsize;
1703 else
1704 contents_size = last_phdr->p_offset + last_phdr->p_filesz;
1706 /* Now we know the size of the whole image we want read in. */
1707 contents = bfd_zmalloc (contents_size);
1708 if (contents == NULL)
1710 free (x_phdrs);
1711 bfd_set_error (bfd_error_no_memory);
1712 return NULL;
1715 for (i = 0; i < i_ehdr.e_phnum; ++i)
1716 /* IA-64 vDSO may have two mappings for one segment, where one mapping
1717 is executable only, and one is read only. We must not use the
1718 executable one. */
1719 if (i_phdrs[i].p_type == PT_LOAD && (i_phdrs[i].p_flags & PF_R))
1721 bfd_vma start = i_phdrs[i].p_offset & -i_phdrs[i].p_align;
1722 bfd_vma end = (i_phdrs[i].p_offset + i_phdrs[i].p_filesz
1723 + i_phdrs[i].p_align - 1) & -i_phdrs[i].p_align;
1724 if (end > (bfd_vma) contents_size)
1725 end = contents_size;
1726 err = target_read_memory ((loadbase + i_phdrs[i].p_vaddr)
1727 & -i_phdrs[i].p_align,
1728 contents + start, end - start);
1729 if (err)
1731 free (x_phdrs);
1732 free (contents);
1733 bfd_set_error (bfd_error_system_call);
1734 errno = err;
1735 return NULL;
1738 free (x_phdrs);
1740 /* If the segments visible in memory didn't include the section headers,
1741 then clear them from the file header. */
1742 if ((bfd_vma) contents_size < (i_ehdr.e_shoff
1743 + i_ehdr.e_shnum * i_ehdr.e_shentsize))
1745 memset (&x_ehdr.e_shoff, 0, sizeof x_ehdr.e_shoff);
1746 memset (&x_ehdr.e_shnum, 0, sizeof x_ehdr.e_shnum);
1747 memset (&x_ehdr.e_shstrndx, 0, sizeof x_ehdr.e_shstrndx);
1750 /* This will normally have been in the first PT_LOAD segment. But it
1751 conceivably could be missing, and we might have just changed it. */
1752 memcpy (contents, &x_ehdr, sizeof x_ehdr);
1754 /* Now we have a memory image of the ELF file contents. Make a BFD. */
1755 bim = bfd_malloc (sizeof (struct bfd_in_memory));
1756 if (bim == NULL)
1758 free (contents);
1759 bfd_set_error (bfd_error_no_memory);
1760 return NULL;
1762 nbfd = _bfd_new_bfd ();
1763 if (nbfd == NULL)
1765 free (bim);
1766 free (contents);
1767 bfd_set_error (bfd_error_no_memory);
1768 return NULL;
1770 nbfd->filename = "<in-memory>";
1771 nbfd->xvec = templ->xvec;
1772 bim->size = contents_size;
1773 bim->buffer = contents;
1774 nbfd->iostream = bim;
1775 nbfd->flags = BFD_IN_MEMORY;
1776 nbfd->direction = read_direction;
1777 nbfd->mtime = time (NULL);
1778 nbfd->mtime_set = TRUE;
1780 if (loadbasep)
1781 *loadbasep = loadbase;
1782 return nbfd;
1785 #include "elfcore.h"
1787 /* Size-dependent data and functions. */
1788 const struct elf_size_info NAME(_bfd_elf,size_info) = {
1789 sizeof (Elf_External_Ehdr),
1790 sizeof (Elf_External_Phdr),
1791 sizeof (Elf_External_Shdr),
1792 sizeof (Elf_External_Rel),
1793 sizeof (Elf_External_Rela),
1794 sizeof (Elf_External_Sym),
1795 sizeof (Elf_External_Dyn),
1796 sizeof (Elf_External_Note),
1799 ARCH_SIZE, LOG_FILE_ALIGN,
1800 ELFCLASS, EV_CURRENT,
1801 elf_write_out_phdrs,
1802 elf_write_shdrs_and_ehdr,
1803 elf_write_relocs,
1804 elf_swap_symbol_in,
1805 elf_swap_symbol_out,
1806 elf_slurp_reloc_table,
1807 elf_slurp_symbol_table,
1808 elf_swap_dyn_in,
1809 elf_swap_dyn_out,
1810 elf_swap_reloc_in,
1811 elf_swap_reloc_out,
1812 elf_swap_reloca_in,
1813 elf_swap_reloca_out