bfd/
[binutils.git] / bfd / elfcode.h
blobd58cf344718304d834ec0d3744d70f38f83f7b63
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;
504 preserve.marker = NULL;
506 /* Read in the ELF header in external format. */
508 if (bfd_bread (&x_ehdr, sizeof (x_ehdr), abfd) != sizeof (x_ehdr))
510 if (bfd_get_error () != bfd_error_system_call)
511 goto got_wrong_format_error;
512 else
513 goto got_no_match;
516 /* Now check to see if we have a valid ELF file, and one that BFD can
517 make use of. The magic number must match, the address size ('class')
518 and byte-swapping must match our XVEC entry, and it must have a
519 section header table (FIXME: See comments re sections at top of this
520 file). */
522 if (! elf_file_p (&x_ehdr)
523 || x_ehdr.e_ident[EI_VERSION] != EV_CURRENT
524 || x_ehdr.e_ident[EI_CLASS] != ELFCLASS)
525 goto got_wrong_format_error;
527 /* Check that file's byte order matches xvec's */
528 switch (x_ehdr.e_ident[EI_DATA])
530 case ELFDATA2MSB: /* Big-endian */
531 if (! bfd_header_big_endian (abfd))
532 goto got_wrong_format_error;
533 break;
534 case ELFDATA2LSB: /* Little-endian */
535 if (! bfd_header_little_endian (abfd))
536 goto got_wrong_format_error;
537 break;
538 case ELFDATANONE: /* No data encoding specified */
539 default: /* Unknown data encoding specified */
540 goto got_wrong_format_error;
543 if (!bfd_preserve_save (abfd, &preserve))
544 goto got_no_match;
546 /* Allocate an instance of the elf_obj_tdata structure and hook it up to
547 the tdata pointer in the bfd. */
549 if (! (*abfd->xvec->_bfd_set_format[bfd_object]) (abfd))
550 goto got_no_match;
551 preserve.marker = elf_tdata (abfd);
553 /* Now that we know the byte order, swap in the rest of the header */
554 i_ehdrp = elf_elfheader (abfd);
555 elf_swap_ehdr_in (abfd, &x_ehdr, i_ehdrp);
556 #if DEBUG & 1
557 elf_debug_file (i_ehdrp);
558 #endif
560 /* Reject ET_CORE (header indicates core file, not object file) */
561 if (i_ehdrp->e_type == ET_CORE)
562 goto got_wrong_format_error;
564 /* If this is a relocatable file and there is no section header
565 table, then we're hosed. */
566 if (i_ehdrp->e_shoff == 0 && i_ehdrp->e_type == ET_REL)
567 goto got_wrong_format_error;
569 /* As a simple sanity check, verify that what BFD thinks is the
570 size of each section header table entry actually matches the size
571 recorded in the file, but only if there are any sections. */
572 if (i_ehdrp->e_shentsize != sizeof (x_shdr) && i_ehdrp->e_shnum != 0)
573 goto got_wrong_format_error;
575 /* Further sanity check. */
576 if (i_ehdrp->e_shoff == 0 && i_ehdrp->e_shnum != 0)
577 goto got_wrong_format_error;
579 ebd = get_elf_backend_data (abfd);
581 /* Check that the ELF e_machine field matches what this particular
582 BFD format expects. */
583 if (ebd->elf_machine_code != i_ehdrp->e_machine
584 && (ebd->elf_machine_alt1 == 0
585 || i_ehdrp->e_machine != ebd->elf_machine_alt1)
586 && (ebd->elf_machine_alt2 == 0
587 || i_ehdrp->e_machine != ebd->elf_machine_alt2))
589 const bfd_target * const *target_ptr;
591 if (ebd->elf_machine_code != EM_NONE)
592 goto got_wrong_format_error;
594 /* This is the generic ELF target. Let it match any ELF target
595 for which we do not have a specific backend. */
596 for (target_ptr = bfd_target_vector; *target_ptr != NULL; target_ptr++)
598 const struct elf_backend_data *back;
600 if ((*target_ptr)->flavour != bfd_target_elf_flavour)
601 continue;
602 back = (const struct elf_backend_data *) (*target_ptr)->backend_data;
603 if (back->elf_machine_code == i_ehdrp->e_machine
604 || (back->elf_machine_alt1 != 0
605 && back->elf_machine_alt1 == i_ehdrp->e_machine)
606 || (back->elf_machine_alt2 != 0
607 && back->elf_machine_alt2 == i_ehdrp->e_machine))
609 /* target_ptr is an ELF backend which matches this
610 object file, so reject the generic ELF target. */
611 goto got_wrong_format_error;
616 if (i_ehdrp->e_type == ET_EXEC)
617 abfd->flags |= EXEC_P;
618 else if (i_ehdrp->e_type == ET_DYN)
619 abfd->flags |= DYNAMIC;
621 if (i_ehdrp->e_phnum > 0)
622 abfd->flags |= D_PAGED;
624 if (! bfd_default_set_arch_mach (abfd, ebd->arch, 0))
626 /* It's OK if this fails for the generic target. */
627 if (ebd->elf_machine_code != EM_NONE)
628 goto got_no_match;
631 if (i_ehdrp->e_shoff != 0)
633 bfd_signed_vma where = i_ehdrp->e_shoff;
635 if (where != (file_ptr) where)
636 goto got_wrong_format_error;
638 /* Seek to the section header table in the file. */
639 if (bfd_seek (abfd, (file_ptr) where, SEEK_SET) != 0)
640 goto got_no_match;
642 /* Read the first section header at index 0, and convert to internal
643 form. */
644 if (bfd_bread (&x_shdr, sizeof x_shdr, abfd) != sizeof (x_shdr))
645 goto got_no_match;
646 elf_swap_shdr_in (abfd, &x_shdr, &i_shdr);
648 /* If the section count is zero, the actual count is in the first
649 section header. */
650 if (i_ehdrp->e_shnum == SHN_UNDEF)
652 i_ehdrp->e_shnum = i_shdr.sh_size;
653 if (i_ehdrp->e_shnum != i_shdr.sh_size
654 || i_ehdrp->e_shnum == 0)
655 goto got_wrong_format_error;
658 /* And similarly for the string table index. */
659 if (i_ehdrp->e_shstrndx == SHN_XINDEX)
661 i_ehdrp->e_shstrndx = i_shdr.sh_link;
662 if (i_ehdrp->e_shstrndx != i_shdr.sh_link)
663 goto got_wrong_format_error;
666 /* Sanity check that we can read all of the section headers.
667 It ought to be good enough to just read the last one. */
668 if (i_ehdrp->e_shnum != 1)
670 /* Check that we don't have a totally silly number of sections. */
671 if (i_ehdrp->e_shnum > (unsigned int) -1 / sizeof (x_shdr)
672 || i_ehdrp->e_shnum > (unsigned int) -1 / sizeof (i_shdr))
673 goto got_wrong_format_error;
675 where += (i_ehdrp->e_shnum - 1) * sizeof (x_shdr);
676 if (where != (file_ptr) where)
677 goto got_wrong_format_error;
678 if ((bfd_size_type) where <= i_ehdrp->e_shoff)
679 goto got_wrong_format_error;
681 if (bfd_seek (abfd, (file_ptr) where, SEEK_SET) != 0)
682 goto got_no_match;
683 if (bfd_bread (&x_shdr, sizeof x_shdr, abfd) != sizeof (x_shdr))
684 goto got_no_match;
686 /* Back to where we were. */
687 where = i_ehdrp->e_shoff + sizeof (x_shdr);
688 if (bfd_seek (abfd, (file_ptr) where, SEEK_SET) != 0)
689 goto got_no_match;
693 /* Allocate space for a copy of the section header table in
694 internal form. */
695 if (i_ehdrp->e_shnum != 0)
697 Elf_Internal_Shdr *shdrp;
698 unsigned int num_sec;
700 amt = sizeof (*i_shdrp) * i_ehdrp->e_shnum;
701 i_shdrp = bfd_alloc (abfd, amt);
702 if (!i_shdrp)
703 goto got_no_match;
704 num_sec = i_ehdrp->e_shnum;
705 if (num_sec > SHN_LORESERVE)
706 num_sec += SHN_HIRESERVE + 1 - SHN_LORESERVE;
707 elf_numsections (abfd) = num_sec;
708 amt = sizeof (i_shdrp) * num_sec;
709 elf_elfsections (abfd) = bfd_alloc (abfd, amt);
710 if (!elf_elfsections (abfd))
711 goto got_no_match;
713 memcpy (i_shdrp, &i_shdr, sizeof (*i_shdrp));
714 shdrp = i_shdrp;
715 shindex = 0;
716 if (num_sec > SHN_LORESERVE)
718 for ( ; shindex < SHN_LORESERVE; shindex++)
719 elf_elfsections (abfd)[shindex] = shdrp++;
720 for ( ; shindex < SHN_HIRESERVE + 1; shindex++)
721 elf_elfsections (abfd)[shindex] = i_shdrp;
723 for ( ; shindex < num_sec; shindex++)
724 elf_elfsections (abfd)[shindex] = shdrp++;
726 /* Read in the rest of the section header table and convert it
727 to internal form. */
728 for (shindex = 1; shindex < i_ehdrp->e_shnum; shindex++)
730 if (bfd_bread (&x_shdr, sizeof x_shdr, abfd) != sizeof (x_shdr))
731 goto got_no_match;
732 elf_swap_shdr_in (abfd, &x_shdr, i_shdrp + shindex);
734 /* Sanity check sh_link and sh_info. */
735 if (! valid_section_index_p (i_shdrp[shindex].sh_link, num_sec))
736 goto got_wrong_format_error;
738 if (((i_shdrp[shindex].sh_flags & SHF_INFO_LINK)
739 || i_shdrp[shindex].sh_type == SHT_RELA
740 || i_shdrp[shindex].sh_type == SHT_REL)
741 && ! valid_section_index_p (i_shdrp[shindex].sh_info, num_sec))
742 goto got_wrong_format_error;
744 /* If the section is loaded, but not page aligned, clear
745 D_PAGED. */
746 if (i_shdrp[shindex].sh_size != 0
747 && (i_shdrp[shindex].sh_flags & SHF_ALLOC) != 0
748 && i_shdrp[shindex].sh_type != SHT_NOBITS
749 && (((i_shdrp[shindex].sh_addr - i_shdrp[shindex].sh_offset)
750 % ebd->minpagesize)
751 != 0))
752 abfd->flags &= ~D_PAGED;
756 /* A further sanity check. */
757 if (i_ehdrp->e_shnum != 0)
759 if (! valid_section_index_p (i_ehdrp->e_shstrndx, elf_numsections (abfd)))
761 /* PR 2257:
762 We used to just goto got_wrong_format_error here
763 but there are binaries in existance for which this test
764 will prevent the binutils from working with them at all.
765 So we are kind, and reset the string index value to 0
766 so that at least some processing can be done. */
767 i_ehdrp->e_shstrndx = SHN_UNDEF;
768 _bfd_error_handler (_("warning: %s has a corrupt string table index - ignoring"), abfd->filename);
771 else if (i_ehdrp->e_shstrndx != SHN_UNDEF)
772 goto got_wrong_format_error;
774 /* Read in the program headers. */
775 if (i_ehdrp->e_phnum == 0)
776 elf_tdata (abfd)->phdr = NULL;
777 else
779 Elf_Internal_Phdr *i_phdr;
780 unsigned int i;
782 amt = i_ehdrp->e_phnum * sizeof (Elf_Internal_Phdr);
783 elf_tdata (abfd)->phdr = bfd_alloc (abfd, amt);
784 if (elf_tdata (abfd)->phdr == NULL)
785 goto got_no_match;
786 if (bfd_seek (abfd, (file_ptr) i_ehdrp->e_phoff, SEEK_SET) != 0)
787 goto got_no_match;
788 i_phdr = elf_tdata (abfd)->phdr;
789 for (i = 0; i < i_ehdrp->e_phnum; i++, i_phdr++)
791 Elf_External_Phdr x_phdr;
793 if (bfd_bread (&x_phdr, sizeof x_phdr, abfd) != sizeof x_phdr)
794 goto got_no_match;
795 elf_swap_phdr_in (abfd, &x_phdr, i_phdr);
799 if (i_ehdrp->e_shstrndx != 0 && i_ehdrp->e_shoff != 0)
801 unsigned int num_sec;
803 /* Once all of the section headers have been read and converted, we
804 can start processing them. Note that the first section header is
805 a dummy placeholder entry, so we ignore it. */
806 num_sec = elf_numsections (abfd);
807 for (shindex = 1; shindex < num_sec; shindex++)
809 if (! bfd_section_from_shdr (abfd, shindex))
810 goto got_no_match;
811 if (shindex == SHN_LORESERVE - 1)
812 shindex += SHN_HIRESERVE + 1 - SHN_LORESERVE;
815 /* Set up ELF sections for SHF_GROUP and SHF_LINK_ORDER. */
816 if (! _bfd_elf_setup_sections (abfd))
817 goto got_wrong_format_error;
820 /* Let the backend double check the format and override global
821 information. */
822 if (ebd->elf_backend_object_p)
824 if (! (*ebd->elf_backend_object_p) (abfd))
825 goto got_wrong_format_error;
828 /* Remember the entry point specified in the ELF file header. */
829 bfd_set_start_address (abfd, i_ehdrp->e_entry);
831 /* If we have created any reloc sections that are associated with
832 debugging sections, mark the reloc sections as debugging as well. */
833 for (s = abfd->sections; s != NULL; s = s->next)
835 if ((elf_section_data (s)->this_hdr.sh_type == SHT_REL
836 || elf_section_data (s)->this_hdr.sh_type == SHT_RELA)
837 && elf_section_data (s)->this_hdr.sh_info > 0)
839 unsigned long targ_index;
840 asection *targ_sec;
842 targ_index = elf_section_data (s)->this_hdr.sh_info;
843 targ_sec = bfd_section_from_elf_index (abfd, targ_index);
844 if (targ_sec != NULL
845 && (targ_sec->flags & SEC_DEBUGGING) != 0)
846 s->flags |= SEC_DEBUGGING;
850 bfd_preserve_finish (abfd, &preserve);
851 return abfd->xvec;
853 got_wrong_format_error:
854 /* There is way too much undoing of half-known state here. The caller,
855 bfd_check_format_matches, really shouldn't iterate on live bfd's to
856 check match/no-match like it does. We have to rely on that a call to
857 bfd_default_set_arch_mach with the previously known mach, undoes what
858 was done by the first bfd_default_set_arch_mach (with mach 0) here.
859 For this to work, only elf-data and the mach may be changed by the
860 target-specific elf_backend_object_p function. Note that saving the
861 whole bfd here and restoring it would be even worse; the first thing
862 you notice is that the cached bfd file position gets out of sync. */
863 bfd_set_error (bfd_error_wrong_format);
865 got_no_match:
866 if (preserve.marker != NULL)
867 bfd_preserve_restore (abfd, &preserve);
868 return NULL;
871 /* ELF .o/exec file writing */
873 /* Write out the relocs. */
875 void
876 elf_write_relocs (bfd *abfd, asection *sec, void *data)
878 bfd_boolean *failedp = data;
879 Elf_Internal_Shdr *rela_hdr;
880 bfd_vma addr_offset;
881 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
882 size_t extsize;
883 bfd_byte *dst_rela;
884 unsigned int idx;
885 asymbol *last_sym;
886 int last_sym_idx;
888 /* If we have already failed, don't do anything. */
889 if (*failedp)
890 return;
892 if ((sec->flags & SEC_RELOC) == 0)
893 return;
895 /* The linker backend writes the relocs out itself, and sets the
896 reloc_count field to zero to inhibit writing them here. Also,
897 sometimes the SEC_RELOC flag gets set even when there aren't any
898 relocs. */
899 if (sec->reloc_count == 0)
900 return;
902 /* If we have opened an existing file for update, reloc_count may be
903 set even though we are not linking. In that case we have nothing
904 to do. */
905 if (sec->orelocation == NULL)
906 return;
908 rela_hdr = &elf_section_data (sec)->rel_hdr;
910 rela_hdr->sh_size = rela_hdr->sh_entsize * sec->reloc_count;
911 rela_hdr->contents = bfd_alloc (abfd, rela_hdr->sh_size);
912 if (rela_hdr->contents == NULL)
914 *failedp = TRUE;
915 return;
918 /* Figure out whether the relocations are RELA or REL relocations. */
919 if (rela_hdr->sh_type == SHT_RELA)
921 swap_out = elf_swap_reloca_out;
922 extsize = sizeof (Elf_External_Rela);
924 else if (rela_hdr->sh_type == SHT_REL)
926 swap_out = elf_swap_reloc_out;
927 extsize = sizeof (Elf_External_Rel);
929 else
930 /* Every relocation section should be either an SHT_RELA or an
931 SHT_REL section. */
932 abort ();
934 /* The address of an ELF reloc is section relative for an object
935 file, and absolute for an executable file or shared library.
936 The address of a BFD reloc is always section relative. */
937 addr_offset = 0;
938 if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
939 addr_offset = sec->vma;
941 /* orelocation has the data, reloc_count has the count... */
942 last_sym = 0;
943 last_sym_idx = 0;
944 dst_rela = rela_hdr->contents;
946 for (idx = 0; idx < sec->reloc_count; idx++, dst_rela += extsize)
948 Elf_Internal_Rela src_rela;
949 arelent *ptr;
950 asymbol *sym;
951 int n;
953 ptr = sec->orelocation[idx];
954 sym = *ptr->sym_ptr_ptr;
955 if (sym == last_sym)
956 n = last_sym_idx;
957 else if (bfd_is_abs_section (sym->section) && sym->value == 0)
958 n = STN_UNDEF;
959 else
961 last_sym = sym;
962 n = _bfd_elf_symbol_from_bfd_symbol (abfd, &sym);
963 if (n < 0)
965 *failedp = TRUE;
966 return;
968 last_sym_idx = n;
971 if ((*ptr->sym_ptr_ptr)->the_bfd != NULL
972 && (*ptr->sym_ptr_ptr)->the_bfd->xvec != abfd->xvec
973 && ! _bfd_elf_validate_reloc (abfd, ptr))
975 *failedp = TRUE;
976 return;
979 src_rela.r_offset = ptr->address + addr_offset;
980 src_rela.r_info = ELF_R_INFO (n, ptr->howto->type);
981 src_rela.r_addend = ptr->addend;
982 (*swap_out) (abfd, &src_rela, dst_rela);
986 /* Write out the program headers. */
989 elf_write_out_phdrs (bfd *abfd,
990 const Elf_Internal_Phdr *phdr,
991 unsigned int count)
993 while (count--)
995 Elf_External_Phdr extphdr;
996 elf_swap_phdr_out (abfd, phdr, &extphdr);
997 if (bfd_bwrite (&extphdr, sizeof (Elf_External_Phdr), abfd)
998 != sizeof (Elf_External_Phdr))
999 return -1;
1000 phdr++;
1002 return 0;
1005 /* Write out the section headers and the ELF file header. */
1007 bfd_boolean
1008 elf_write_shdrs_and_ehdr (bfd *abfd)
1010 Elf_External_Ehdr x_ehdr; /* Elf file header, external form */
1011 Elf_Internal_Ehdr *i_ehdrp; /* Elf file header, internal form */
1012 Elf_External_Shdr *x_shdrp; /* Section header table, external form */
1013 Elf_Internal_Shdr **i_shdrp; /* Section header table, internal form */
1014 unsigned int count;
1015 bfd_size_type amt;
1017 i_ehdrp = elf_elfheader (abfd);
1018 i_shdrp = elf_elfsections (abfd);
1020 /* swap the header before spitting it out... */
1022 #if DEBUG & 1
1023 elf_debug_file (i_ehdrp);
1024 #endif
1025 elf_swap_ehdr_out (abfd, i_ehdrp, &x_ehdr);
1026 amt = sizeof (x_ehdr);
1027 if (bfd_seek (abfd, (file_ptr) 0, SEEK_SET) != 0
1028 || bfd_bwrite (&x_ehdr, amt, abfd) != amt)
1029 return FALSE;
1031 /* Some fields in the first section header handle overflow of ehdr
1032 fields. */
1033 if (i_ehdrp->e_shnum >= SHN_LORESERVE)
1034 i_shdrp[0]->sh_size = i_ehdrp->e_shnum;
1035 if (i_ehdrp->e_shstrndx >= SHN_LORESERVE)
1036 i_shdrp[0]->sh_link = i_ehdrp->e_shstrndx;
1038 /* at this point we've concocted all the ELF sections... */
1039 amt = i_ehdrp->e_shnum;
1040 amt *= sizeof (*x_shdrp);
1041 x_shdrp = bfd_alloc (abfd, amt);
1042 if (!x_shdrp)
1043 return FALSE;
1045 for (count = 0; count < i_ehdrp->e_shnum; i_shdrp++, count++)
1047 #if DEBUG & 2
1048 elf_debug_section (count, *i_shdrp);
1049 #endif
1050 elf_swap_shdr_out (abfd, *i_shdrp, x_shdrp + count);
1052 if (count == SHN_LORESERVE - 1)
1053 i_shdrp += SHN_HIRESERVE + 1 - SHN_LORESERVE;
1055 if (bfd_seek (abfd, (file_ptr) i_ehdrp->e_shoff, SEEK_SET) != 0
1056 || bfd_bwrite (x_shdrp, amt, abfd) != amt)
1057 return FALSE;
1059 /* need to dump the string table too... */
1061 return TRUE;
1064 long
1065 elf_slurp_symbol_table (bfd *abfd, asymbol **symptrs, bfd_boolean dynamic)
1067 Elf_Internal_Shdr *hdr;
1068 Elf_Internal_Shdr *verhdr;
1069 unsigned long symcount; /* Number of external ELF symbols */
1070 elf_symbol_type *sym; /* Pointer to current bfd symbol */
1071 elf_symbol_type *symbase; /* Buffer for generated bfd symbols */
1072 Elf_Internal_Sym *isym;
1073 Elf_Internal_Sym *isymend;
1074 Elf_Internal_Sym *isymbuf = NULL;
1075 Elf_External_Versym *xver;
1076 Elf_External_Versym *xverbuf = NULL;
1077 const struct elf_backend_data *ebd;
1078 bfd_size_type amt;
1080 /* Read each raw ELF symbol, converting from external ELF form to
1081 internal ELF form, and then using the information to create a
1082 canonical bfd symbol table entry.
1084 Note that we allocate the initial bfd canonical symbol buffer
1085 based on a one-to-one mapping of the ELF symbols to canonical
1086 symbols. We actually use all the ELF symbols, so there will be no
1087 space left over at the end. When we have all the symbols, we
1088 build the caller's pointer vector. */
1090 if (! dynamic)
1092 hdr = &elf_tdata (abfd)->symtab_hdr;
1093 verhdr = NULL;
1095 else
1097 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
1098 if (elf_dynversym (abfd) == 0)
1099 verhdr = NULL;
1100 else
1101 verhdr = &elf_tdata (abfd)->dynversym_hdr;
1102 if ((elf_tdata (abfd)->dynverdef_section != 0
1103 && elf_tdata (abfd)->verdef == NULL)
1104 || (elf_tdata (abfd)->dynverref_section != 0
1105 && elf_tdata (abfd)->verref == NULL))
1107 if (!_bfd_elf_slurp_version_tables (abfd, FALSE))
1108 return -1;
1112 ebd = get_elf_backend_data (abfd);
1113 symcount = hdr->sh_size / sizeof (Elf_External_Sym);
1114 if (symcount == 0)
1115 sym = symbase = NULL;
1116 else
1118 isymbuf = bfd_elf_get_elf_syms (abfd, hdr, symcount, 0,
1119 NULL, NULL, NULL);
1120 if (isymbuf == NULL)
1121 return -1;
1123 amt = symcount;
1124 amt *= sizeof (elf_symbol_type);
1125 symbase = bfd_zalloc (abfd, amt);
1126 if (symbase == (elf_symbol_type *) NULL)
1127 goto error_return;
1129 /* Read the raw ELF version symbol information. */
1130 if (verhdr != NULL
1131 && verhdr->sh_size / sizeof (Elf_External_Versym) != symcount)
1133 (*_bfd_error_handler)
1134 (_("%s: version count (%ld) does not match symbol count (%ld)"),
1135 abfd->filename,
1136 (long) (verhdr->sh_size / sizeof (Elf_External_Versym)),
1137 symcount);
1139 /* Slurp in the symbols without the version information,
1140 since that is more helpful than just quitting. */
1141 verhdr = NULL;
1144 if (verhdr != NULL)
1146 if (bfd_seek (abfd, verhdr->sh_offset, SEEK_SET) != 0)
1147 goto error_return;
1149 xverbuf = bfd_malloc (verhdr->sh_size);
1150 if (xverbuf == NULL && verhdr->sh_size != 0)
1151 goto error_return;
1153 if (bfd_bread (xverbuf, verhdr->sh_size, abfd) != verhdr->sh_size)
1154 goto error_return;
1157 /* Skip first symbol, which is a null dummy. */
1158 xver = xverbuf;
1159 if (xver != NULL)
1160 ++xver;
1161 isymend = isymbuf + symcount;
1162 for (isym = isymbuf + 1, sym = symbase; isym < isymend; isym++, sym++)
1164 memcpy (&sym->internal_elf_sym, isym, sizeof (Elf_Internal_Sym));
1165 sym->symbol.the_bfd = abfd;
1167 sym->symbol.name = bfd_elf_sym_name (abfd, hdr, isym, NULL);
1169 sym->symbol.value = isym->st_value;
1171 if (isym->st_shndx == SHN_UNDEF)
1173 sym->symbol.section = bfd_und_section_ptr;
1175 else if (isym->st_shndx < SHN_LORESERVE
1176 || isym->st_shndx > SHN_HIRESERVE)
1178 sym->symbol.section = bfd_section_from_elf_index (abfd,
1179 isym->st_shndx);
1180 if (sym->symbol.section == NULL)
1182 /* This symbol is in a section for which we did not
1183 create a BFD section. Just use bfd_abs_section,
1184 although it is wrong. FIXME. */
1185 sym->symbol.section = bfd_abs_section_ptr;
1188 else if (isym->st_shndx == SHN_ABS)
1190 sym->symbol.section = bfd_abs_section_ptr;
1192 else if (isym->st_shndx == SHN_COMMON)
1194 sym->symbol.section = bfd_com_section_ptr;
1195 /* Elf puts the alignment into the `value' field, and
1196 the size into the `size' field. BFD wants to see the
1197 size in the value field, and doesn't care (at the
1198 moment) about the alignment. */
1199 sym->symbol.value = isym->st_size;
1201 else
1202 sym->symbol.section = bfd_abs_section_ptr;
1204 /* If this is a relocatable file, then the symbol value is
1205 already section relative. */
1206 if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
1207 sym->symbol.value -= sym->symbol.section->vma;
1209 switch (ELF_ST_BIND (isym->st_info))
1211 case STB_LOCAL:
1212 sym->symbol.flags |= BSF_LOCAL;
1213 break;
1214 case STB_GLOBAL:
1215 if (isym->st_shndx != SHN_UNDEF && isym->st_shndx != SHN_COMMON)
1216 sym->symbol.flags |= BSF_GLOBAL;
1217 break;
1218 case STB_WEAK:
1219 sym->symbol.flags |= BSF_WEAK;
1220 break;
1223 switch (ELF_ST_TYPE (isym->st_info))
1225 case STT_SECTION:
1226 sym->symbol.flags |= BSF_SECTION_SYM | BSF_DEBUGGING;
1227 break;
1228 case STT_FILE:
1229 sym->symbol.flags |= BSF_FILE | BSF_DEBUGGING;
1230 break;
1231 case STT_FUNC:
1232 sym->symbol.flags |= BSF_FUNCTION;
1233 break;
1234 case STT_OBJECT:
1235 sym->symbol.flags |= BSF_OBJECT;
1236 break;
1237 case STT_TLS:
1238 sym->symbol.flags |= BSF_THREAD_LOCAL;
1239 break;
1242 if (dynamic)
1243 sym->symbol.flags |= BSF_DYNAMIC;
1245 if (xver != NULL)
1247 Elf_Internal_Versym iversym;
1249 _bfd_elf_swap_versym_in (abfd, xver, &iversym);
1250 sym->version = iversym.vs_vers;
1251 xver++;
1254 /* Do some backend-specific processing on this symbol. */
1255 if (ebd->elf_backend_symbol_processing)
1256 (*ebd->elf_backend_symbol_processing) (abfd, &sym->symbol);
1260 /* Do some backend-specific processing on this symbol table. */
1261 if (ebd->elf_backend_symbol_table_processing)
1262 (*ebd->elf_backend_symbol_table_processing) (abfd, symbase, symcount);
1264 /* We rely on the zalloc to clear out the final symbol entry. */
1266 symcount = sym - symbase;
1268 /* Fill in the user's symbol pointer vector if needed. */
1269 if (symptrs)
1271 long l = symcount;
1273 sym = symbase;
1274 while (l-- > 0)
1276 *symptrs++ = &sym->symbol;
1277 sym++;
1279 *symptrs = 0; /* Final null pointer */
1282 if (xverbuf != NULL)
1283 free (xverbuf);
1284 if (isymbuf != NULL && hdr->contents != (unsigned char *) isymbuf)
1285 free (isymbuf);
1286 return symcount;
1288 error_return:
1289 if (xverbuf != NULL)
1290 free (xverbuf);
1291 if (isymbuf != NULL && hdr->contents != (unsigned char *) isymbuf)
1292 free (isymbuf);
1293 return -1;
1296 /* Read relocations for ASECT from REL_HDR. There are RELOC_COUNT of
1297 them. */
1299 static bfd_boolean
1300 elf_slurp_reloc_table_from_section (bfd *abfd,
1301 asection *asect,
1302 Elf_Internal_Shdr *rel_hdr,
1303 bfd_size_type reloc_count,
1304 arelent *relents,
1305 asymbol **symbols,
1306 bfd_boolean dynamic)
1308 const struct elf_backend_data * const ebd = get_elf_backend_data (abfd);
1309 void *allocated = NULL;
1310 bfd_byte *native_relocs;
1311 arelent *relent;
1312 unsigned int i;
1313 int entsize;
1314 unsigned int symcount;
1316 allocated = bfd_malloc (rel_hdr->sh_size);
1317 if (allocated == NULL)
1318 goto error_return;
1320 if (bfd_seek (abfd, rel_hdr->sh_offset, SEEK_SET) != 0
1321 || (bfd_bread (allocated, rel_hdr->sh_size, abfd)
1322 != rel_hdr->sh_size))
1323 goto error_return;
1325 native_relocs = allocated;
1327 entsize = rel_hdr->sh_entsize;
1328 BFD_ASSERT (entsize == sizeof (Elf_External_Rel)
1329 || entsize == sizeof (Elf_External_Rela));
1331 if (dynamic)
1332 symcount = bfd_get_dynamic_symcount (abfd);
1333 else
1334 symcount = bfd_get_symcount (abfd);
1336 for (i = 0, relent = relents;
1337 i < reloc_count;
1338 i++, relent++, native_relocs += entsize)
1340 Elf_Internal_Rela rela;
1342 if (entsize == sizeof (Elf_External_Rela))
1343 elf_swap_reloca_in (abfd, native_relocs, &rela);
1344 else
1345 elf_swap_reloc_in (abfd, native_relocs, &rela);
1347 /* The address of an ELF reloc is section relative for an object
1348 file, and absolute for an executable file or shared library.
1349 The address of a normal BFD reloc is always section relative,
1350 and the address of a dynamic reloc is absolute.. */
1351 if ((abfd->flags & (EXEC_P | DYNAMIC)) == 0 || dynamic)
1352 relent->address = rela.r_offset;
1353 else
1354 relent->address = rela.r_offset - asect->vma;
1356 if (ELF_R_SYM (rela.r_info) == 0)
1357 relent->sym_ptr_ptr = bfd_abs_section_ptr->symbol_ptr_ptr;
1358 else if (ELF_R_SYM (rela.r_info) > symcount)
1360 (*_bfd_error_handler)
1361 (_("%s(%s): relocation %d has invalid symbol index %ld"),
1362 abfd->filename, asect->name, i, ELF_R_SYM (rela.r_info));
1363 relent->sym_ptr_ptr = bfd_abs_section.symbol_ptr_ptr;
1365 else
1367 asymbol **ps;
1369 ps = symbols + ELF_R_SYM (rela.r_info) - 1;
1371 relent->sym_ptr_ptr = ps;
1374 relent->addend = rela.r_addend;
1376 if ((entsize == sizeof (Elf_External_Rela)
1377 && ebd->elf_info_to_howto != NULL)
1378 || ebd->elf_info_to_howto_rel == NULL)
1379 (*ebd->elf_info_to_howto) (abfd, relent, &rela);
1380 else
1381 (*ebd->elf_info_to_howto_rel) (abfd, relent, &rela);
1384 if (allocated != NULL)
1385 free (allocated);
1387 return TRUE;
1389 error_return:
1390 if (allocated != NULL)
1391 free (allocated);
1392 return FALSE;
1395 /* Read in and swap the external relocs. */
1397 bfd_boolean
1398 elf_slurp_reloc_table (bfd *abfd,
1399 asection *asect,
1400 asymbol **symbols,
1401 bfd_boolean dynamic)
1403 struct bfd_elf_section_data * const d = elf_section_data (asect);
1404 Elf_Internal_Shdr *rel_hdr;
1405 Elf_Internal_Shdr *rel_hdr2;
1406 bfd_size_type reloc_count;
1407 bfd_size_type reloc_count2;
1408 arelent *relents;
1409 bfd_size_type amt;
1411 if (asect->relocation != NULL)
1412 return TRUE;
1414 if (! dynamic)
1416 if ((asect->flags & SEC_RELOC) == 0
1417 || asect->reloc_count == 0)
1418 return TRUE;
1420 rel_hdr = &d->rel_hdr;
1421 reloc_count = NUM_SHDR_ENTRIES (rel_hdr);
1422 rel_hdr2 = d->rel_hdr2;
1423 reloc_count2 = (rel_hdr2 ? NUM_SHDR_ENTRIES (rel_hdr2) : 0);
1425 BFD_ASSERT (asect->reloc_count == reloc_count + reloc_count2);
1426 BFD_ASSERT (asect->rel_filepos == rel_hdr->sh_offset
1427 || (rel_hdr2 && asect->rel_filepos == rel_hdr2->sh_offset));
1430 else
1432 /* Note that ASECT->RELOC_COUNT tends not to be accurate in this
1433 case because relocations against this section may use the
1434 dynamic symbol table, and in that case bfd_section_from_shdr
1435 in elf.c does not update the RELOC_COUNT. */
1436 if (asect->size == 0)
1437 return TRUE;
1439 rel_hdr = &d->this_hdr;
1440 reloc_count = NUM_SHDR_ENTRIES (rel_hdr);
1441 rel_hdr2 = NULL;
1442 reloc_count2 = 0;
1445 amt = (reloc_count + reloc_count2) * sizeof (arelent);
1446 relents = bfd_alloc (abfd, amt);
1447 if (relents == NULL)
1448 return FALSE;
1450 if (!elf_slurp_reloc_table_from_section (abfd, asect,
1451 rel_hdr, reloc_count,
1452 relents,
1453 symbols, dynamic))
1454 return FALSE;
1456 if (rel_hdr2
1457 && !elf_slurp_reloc_table_from_section (abfd, asect,
1458 rel_hdr2, reloc_count2,
1459 relents + reloc_count,
1460 symbols, dynamic))
1461 return FALSE;
1463 asect->relocation = relents;
1464 return TRUE;
1467 #if DEBUG & 2
1468 static void
1469 elf_debug_section (int num, Elf_Internal_Shdr *hdr)
1471 fprintf (stderr, "\nSection#%d '%s' 0x%.8lx\n", num,
1472 hdr->bfd_section != NULL ? hdr->bfd_section->name : "",
1473 (long) hdr);
1474 fprintf (stderr,
1475 "sh_name = %ld\tsh_type = %ld\tsh_flags = %ld\n",
1476 (long) hdr->sh_name,
1477 (long) hdr->sh_type,
1478 (long) hdr->sh_flags);
1479 fprintf (stderr,
1480 "sh_addr = %ld\tsh_offset = %ld\tsh_size = %ld\n",
1481 (long) hdr->sh_addr,
1482 (long) hdr->sh_offset,
1483 (long) hdr->sh_size);
1484 fprintf (stderr,
1485 "sh_link = %ld\tsh_info = %ld\tsh_addralign = %ld\n",
1486 (long) hdr->sh_link,
1487 (long) hdr->sh_info,
1488 (long) hdr->sh_addralign);
1489 fprintf (stderr, "sh_entsize = %ld\n",
1490 (long) hdr->sh_entsize);
1491 fflush (stderr);
1493 #endif
1495 #if DEBUG & 1
1496 static void
1497 elf_debug_file (Elf_Internal_Ehdr *ehdrp)
1499 fprintf (stderr, "e_entry = 0x%.8lx\n", (long) ehdrp->e_entry);
1500 fprintf (stderr, "e_phoff = %ld\n", (long) ehdrp->e_phoff);
1501 fprintf (stderr, "e_phnum = %ld\n", (long) ehdrp->e_phnum);
1502 fprintf (stderr, "e_phentsize = %ld\n", (long) ehdrp->e_phentsize);
1503 fprintf (stderr, "e_shoff = %ld\n", (long) ehdrp->e_shoff);
1504 fprintf (stderr, "e_shnum = %ld\n", (long) ehdrp->e_shnum);
1505 fprintf (stderr, "e_shentsize = %ld\n", (long) ehdrp->e_shentsize);
1507 #endif
1509 /* Create a new BFD as if by bfd_openr. Rather than opening a file,
1510 reconstruct an ELF file by reading the segments out of remote memory
1511 based on the ELF file header at EHDR_VMA and the ELF program headers it
1512 points to. If not null, *LOADBASEP is filled in with the difference
1513 between the VMAs from which the segments were read, and the VMAs the
1514 file headers (and hence BFD's idea of each section's VMA) put them at.
1516 The function TARGET_READ_MEMORY is called to copy LEN bytes from the
1517 remote memory at target address VMA into the local buffer at MYADDR; it
1518 should return zero on success or an `errno' code on failure. TEMPL must
1519 be a BFD for a target with the word size and byte order found in the
1520 remote memory. */
1522 bfd *
1523 NAME(_bfd_elf,bfd_from_remote_memory)
1524 (bfd *templ,
1525 bfd_vma ehdr_vma,
1526 bfd_vma *loadbasep,
1527 int (*target_read_memory) (bfd_vma, bfd_byte *, int))
1529 Elf_External_Ehdr x_ehdr; /* Elf file header, external form */
1530 Elf_Internal_Ehdr i_ehdr; /* Elf file header, internal form */
1531 Elf_External_Phdr *x_phdrs;
1532 Elf_Internal_Phdr *i_phdrs, *last_phdr;
1533 bfd *nbfd;
1534 struct bfd_in_memory *bim;
1535 int contents_size;
1536 bfd_byte *contents;
1537 int err;
1538 unsigned int i;
1539 bfd_vma loadbase;
1541 /* Read in the ELF header in external format. */
1542 err = target_read_memory (ehdr_vma, (bfd_byte *) &x_ehdr, sizeof x_ehdr);
1543 if (err)
1545 bfd_set_error (bfd_error_system_call);
1546 errno = err;
1547 return NULL;
1550 /* Now check to see if we have a valid ELF file, and one that BFD can
1551 make use of. The magic number must match, the address size ('class')
1552 and byte-swapping must match our XVEC entry. */
1554 if (! elf_file_p (&x_ehdr)
1555 || x_ehdr.e_ident[EI_VERSION] != EV_CURRENT
1556 || x_ehdr.e_ident[EI_CLASS] != ELFCLASS)
1558 bfd_set_error (bfd_error_wrong_format);
1559 return NULL;
1562 /* Check that file's byte order matches xvec's */
1563 switch (x_ehdr.e_ident[EI_DATA])
1565 case ELFDATA2MSB: /* Big-endian */
1566 if (! bfd_header_big_endian (templ))
1568 bfd_set_error (bfd_error_wrong_format);
1569 return NULL;
1571 break;
1572 case ELFDATA2LSB: /* Little-endian */
1573 if (! bfd_header_little_endian (templ))
1575 bfd_set_error (bfd_error_wrong_format);
1576 return NULL;
1578 break;
1579 case ELFDATANONE: /* No data encoding specified */
1580 default: /* Unknown data encoding specified */
1581 bfd_set_error (bfd_error_wrong_format);
1582 return NULL;
1585 elf_swap_ehdr_in (templ, &x_ehdr, &i_ehdr);
1587 /* The file header tells where to find the program headers.
1588 These are what we use to actually choose what to read. */
1590 if (i_ehdr.e_phentsize != sizeof (Elf_External_Phdr) || i_ehdr.e_phnum == 0)
1592 bfd_set_error (bfd_error_wrong_format);
1593 return NULL;
1596 x_phdrs = bfd_malloc (i_ehdr.e_phnum * (sizeof *x_phdrs + sizeof *i_phdrs));
1597 if (x_phdrs == NULL)
1599 bfd_set_error (bfd_error_no_memory);
1600 return NULL;
1602 err = target_read_memory (ehdr_vma + i_ehdr.e_phoff, (bfd_byte *) x_phdrs,
1603 i_ehdr.e_phnum * sizeof x_phdrs[0]);
1604 if (err)
1606 free (x_phdrs);
1607 bfd_set_error (bfd_error_system_call);
1608 errno = err;
1609 return NULL;
1611 i_phdrs = (Elf_Internal_Phdr *) &x_phdrs[i_ehdr.e_phnum];
1613 contents_size = 0;
1614 last_phdr = NULL;
1615 loadbase = ehdr_vma;
1616 for (i = 0; i < i_ehdr.e_phnum; ++i)
1618 elf_swap_phdr_in (templ, &x_phdrs[i], &i_phdrs[i]);
1619 /* IA-64 vDSO may have two mappings for one segment, where one mapping
1620 is executable only, and one is read only. We must not use the
1621 executable one. */
1622 if (i_phdrs[i].p_type == PT_LOAD && (i_phdrs[i].p_flags & PF_R))
1624 bfd_vma segment_end;
1625 segment_end = (i_phdrs[i].p_offset + i_phdrs[i].p_filesz
1626 + i_phdrs[i].p_align - 1) & -i_phdrs[i].p_align;
1627 if (segment_end > (bfd_vma) contents_size)
1628 contents_size = segment_end;
1630 if ((i_phdrs[i].p_offset & -i_phdrs[i].p_align) == 0)
1631 loadbase = ehdr_vma - (i_phdrs[i].p_vaddr & -i_phdrs[i].p_align);
1633 last_phdr = &i_phdrs[i];
1636 if (last_phdr == NULL)
1638 /* There were no PT_LOAD segments, so we don't have anything to read. */
1639 free (x_phdrs);
1640 bfd_set_error (bfd_error_wrong_format);
1641 return NULL;
1644 /* Trim the last segment so we don't bother with zeros in the last page
1645 that are off the end of the file. However, if the extra bit in that
1646 page includes the section headers, keep them. */
1647 if ((bfd_vma) contents_size > last_phdr->p_offset + last_phdr->p_filesz
1648 && (bfd_vma) contents_size >= (i_ehdr.e_shoff
1649 + i_ehdr.e_shnum * i_ehdr.e_shentsize))
1651 contents_size = last_phdr->p_offset + last_phdr->p_filesz;
1652 if ((bfd_vma) contents_size < (i_ehdr.e_shoff
1653 + i_ehdr.e_shnum * i_ehdr.e_shentsize))
1654 contents_size = i_ehdr.e_shoff + i_ehdr.e_shnum * i_ehdr.e_shentsize;
1656 else
1657 contents_size = last_phdr->p_offset + last_phdr->p_filesz;
1659 /* Now we know the size of the whole image we want read in. */
1660 contents = bfd_zmalloc (contents_size);
1661 if (contents == NULL)
1663 free (x_phdrs);
1664 bfd_set_error (bfd_error_no_memory);
1665 return NULL;
1668 for (i = 0; i < i_ehdr.e_phnum; ++i)
1669 /* IA-64 vDSO may have two mappings for one segment, where one mapping
1670 is executable only, and one is read only. We must not use the
1671 executable one. */
1672 if (i_phdrs[i].p_type == PT_LOAD && (i_phdrs[i].p_flags & PF_R))
1674 bfd_vma start = i_phdrs[i].p_offset & -i_phdrs[i].p_align;
1675 bfd_vma end = (i_phdrs[i].p_offset + i_phdrs[i].p_filesz
1676 + i_phdrs[i].p_align - 1) & -i_phdrs[i].p_align;
1677 if (end > (bfd_vma) contents_size)
1678 end = contents_size;
1679 err = target_read_memory ((loadbase + i_phdrs[i].p_vaddr)
1680 & -i_phdrs[i].p_align,
1681 contents + start, end - start);
1682 if (err)
1684 free (x_phdrs);
1685 free (contents);
1686 bfd_set_error (bfd_error_system_call);
1687 errno = err;
1688 return NULL;
1691 free (x_phdrs);
1693 /* If the segments visible in memory didn't include the section headers,
1694 then clear them from the file header. */
1695 if ((bfd_vma) contents_size < (i_ehdr.e_shoff
1696 + i_ehdr.e_shnum * i_ehdr.e_shentsize))
1698 memset (&x_ehdr.e_shoff, 0, sizeof x_ehdr.e_shoff);
1699 memset (&x_ehdr.e_shnum, 0, sizeof x_ehdr.e_shnum);
1700 memset (&x_ehdr.e_shstrndx, 0, sizeof x_ehdr.e_shstrndx);
1703 /* This will normally have been in the first PT_LOAD segment. But it
1704 conceivably could be missing, and we might have just changed it. */
1705 memcpy (contents, &x_ehdr, sizeof x_ehdr);
1707 /* Now we have a memory image of the ELF file contents. Make a BFD. */
1708 bim = bfd_malloc (sizeof (struct bfd_in_memory));
1709 if (bim == NULL)
1711 free (contents);
1712 bfd_set_error (bfd_error_no_memory);
1713 return NULL;
1715 nbfd = _bfd_new_bfd ();
1716 if (nbfd == NULL)
1718 free (bim);
1719 free (contents);
1720 bfd_set_error (bfd_error_no_memory);
1721 return NULL;
1723 nbfd->filename = "<in-memory>";
1724 nbfd->xvec = templ->xvec;
1725 bim->size = contents_size;
1726 bim->buffer = contents;
1727 nbfd->iostream = bim;
1728 nbfd->flags = BFD_IN_MEMORY;
1729 nbfd->direction = read_direction;
1730 nbfd->mtime = time (NULL);
1731 nbfd->mtime_set = TRUE;
1733 if (loadbasep)
1734 *loadbasep = loadbase;
1735 return nbfd;
1738 #include "elfcore.h"
1740 /* Size-dependent data and functions. */
1741 const struct elf_size_info NAME(_bfd_elf,size_info) = {
1742 sizeof (Elf_External_Ehdr),
1743 sizeof (Elf_External_Phdr),
1744 sizeof (Elf_External_Shdr),
1745 sizeof (Elf_External_Rel),
1746 sizeof (Elf_External_Rela),
1747 sizeof (Elf_External_Sym),
1748 sizeof (Elf_External_Dyn),
1749 sizeof (Elf_External_Note),
1752 ARCH_SIZE, LOG_FILE_ALIGN,
1753 ELFCLASS, EV_CURRENT,
1754 elf_write_out_phdrs,
1755 elf_write_shdrs_and_ehdr,
1756 elf_write_relocs,
1757 elf_swap_symbol_in,
1758 elf_swap_symbol_out,
1759 elf_slurp_reloc_table,
1760 elf_slurp_symbol_table,
1761 elf_swap_dyn_in,
1762 elf_swap_dyn_out,
1763 elf_swap_reloc_in,
1764 elf_swap_reloc_out,
1765 elf_swap_reloca_in,
1766 elf_swap_reloca_out