2006-08-08 Peter S. Mazinger <ps.m@gmx.net>
[binutils.git] / bfd / elfcode.h
bloba285a133088321287e98baf78eb83222c8242ba2
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 void
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 abort ();
192 dst->st_shndx = H_GET_32 (abfd, shndx->est_shndx);
196 /* Translate an ELF symbol in internal format into an ELF symbol in external
197 format. */
199 void
200 elf_swap_symbol_out (bfd *abfd,
201 const Elf_Internal_Sym *src,
202 void *cdst,
203 void *shndx)
205 unsigned int tmp;
206 Elf_External_Sym *dst = cdst;
207 H_PUT_32 (abfd, src->st_name, dst->st_name);
208 H_PUT_WORD (abfd, src->st_value, dst->st_value);
209 H_PUT_WORD (abfd, src->st_size, dst->st_size);
210 H_PUT_8 (abfd, src->st_info, dst->st_info);
211 H_PUT_8 (abfd, src->st_other, dst->st_other);
212 tmp = src->st_shndx;
213 if (tmp > SHN_HIRESERVE)
215 if (shndx == NULL)
216 abort ();
217 H_PUT_32 (abfd, tmp, shndx);
218 tmp = SHN_XINDEX;
220 H_PUT_16 (abfd, tmp, dst->st_shndx);
223 /* Translate an ELF file header in external format into an ELF file header in
224 internal format. */
226 static void
227 elf_swap_ehdr_in (bfd *abfd,
228 const Elf_External_Ehdr *src,
229 Elf_Internal_Ehdr *dst)
231 int signed_vma = get_elf_backend_data (abfd)->sign_extend_vma;
232 memcpy (dst->e_ident, src->e_ident, EI_NIDENT);
233 dst->e_type = H_GET_16 (abfd, src->e_type);
234 dst->e_machine = H_GET_16 (abfd, src->e_machine);
235 dst->e_version = H_GET_32 (abfd, src->e_version);
236 if (signed_vma)
237 dst->e_entry = H_GET_SIGNED_WORD (abfd, src->e_entry);
238 else
239 dst->e_entry = H_GET_WORD (abfd, src->e_entry);
240 dst->e_phoff = H_GET_WORD (abfd, src->e_phoff);
241 dst->e_shoff = H_GET_WORD (abfd, src->e_shoff);
242 dst->e_flags = H_GET_32 (abfd, src->e_flags);
243 dst->e_ehsize = H_GET_16 (abfd, src->e_ehsize);
244 dst->e_phentsize = H_GET_16 (abfd, src->e_phentsize);
245 dst->e_phnum = H_GET_16 (abfd, src->e_phnum);
246 dst->e_shentsize = H_GET_16 (abfd, src->e_shentsize);
247 dst->e_shnum = H_GET_16 (abfd, src->e_shnum);
248 dst->e_shstrndx = H_GET_16 (abfd, src->e_shstrndx);
251 /* Translate an ELF file header in internal format into an ELF file header in
252 external format. */
254 static void
255 elf_swap_ehdr_out (bfd *abfd,
256 const Elf_Internal_Ehdr *src,
257 Elf_External_Ehdr *dst)
259 unsigned int tmp;
260 int signed_vma = get_elf_backend_data (abfd)->sign_extend_vma;
261 memcpy (dst->e_ident, src->e_ident, EI_NIDENT);
262 /* note that all elements of dst are *arrays of unsigned char* already... */
263 H_PUT_16 (abfd, src->e_type, dst->e_type);
264 H_PUT_16 (abfd, src->e_machine, dst->e_machine);
265 H_PUT_32 (abfd, src->e_version, dst->e_version);
266 if (signed_vma)
267 H_PUT_SIGNED_WORD (abfd, src->e_entry, dst->e_entry);
268 else
269 H_PUT_WORD (abfd, src->e_entry, dst->e_entry);
270 H_PUT_WORD (abfd, src->e_phoff, dst->e_phoff);
271 H_PUT_WORD (abfd, src->e_shoff, dst->e_shoff);
272 H_PUT_32 (abfd, src->e_flags, dst->e_flags);
273 H_PUT_16 (abfd, src->e_ehsize, dst->e_ehsize);
274 H_PUT_16 (abfd, src->e_phentsize, dst->e_phentsize);
275 H_PUT_16 (abfd, src->e_phnum, dst->e_phnum);
276 H_PUT_16 (abfd, src->e_shentsize, dst->e_shentsize);
277 tmp = src->e_shnum;
278 if (tmp >= SHN_LORESERVE)
279 tmp = SHN_UNDEF;
280 H_PUT_16 (abfd, tmp, dst->e_shnum);
281 tmp = src->e_shstrndx;
282 if (tmp >= SHN_LORESERVE)
283 tmp = SHN_XINDEX;
284 H_PUT_16 (abfd, tmp, dst->e_shstrndx);
287 /* Translate an ELF section header table entry in external format into an
288 ELF section header table entry in internal format. */
290 static void
291 elf_swap_shdr_in (bfd *abfd,
292 const Elf_External_Shdr *src,
293 Elf_Internal_Shdr *dst)
295 int signed_vma = get_elf_backend_data (abfd)->sign_extend_vma;
297 dst->sh_name = H_GET_32 (abfd, src->sh_name);
298 dst->sh_type = H_GET_32 (abfd, src->sh_type);
299 dst->sh_flags = H_GET_WORD (abfd, src->sh_flags);
300 if (signed_vma)
301 dst->sh_addr = H_GET_SIGNED_WORD (abfd, src->sh_addr);
302 else
303 dst->sh_addr = H_GET_WORD (abfd, src->sh_addr);
304 dst->sh_offset = H_GET_WORD (abfd, src->sh_offset);
305 dst->sh_size = H_GET_WORD (abfd, src->sh_size);
306 dst->sh_link = H_GET_32 (abfd, src->sh_link);
307 dst->sh_info = H_GET_32 (abfd, src->sh_info);
308 dst->sh_addralign = H_GET_WORD (abfd, src->sh_addralign);
309 dst->sh_entsize = H_GET_WORD (abfd, src->sh_entsize);
310 dst->bfd_section = NULL;
311 dst->contents = NULL;
314 /* Translate an ELF section header table entry in internal format into an
315 ELF section header table entry in external format. */
317 static void
318 elf_swap_shdr_out (bfd *abfd,
319 const Elf_Internal_Shdr *src,
320 Elf_External_Shdr *dst)
322 /* note that all elements of dst are *arrays of unsigned char* already... */
323 H_PUT_32 (abfd, src->sh_name, dst->sh_name);
324 H_PUT_32 (abfd, src->sh_type, dst->sh_type);
325 H_PUT_WORD (abfd, src->sh_flags, dst->sh_flags);
326 H_PUT_WORD (abfd, src->sh_addr, dst->sh_addr);
327 H_PUT_WORD (abfd, src->sh_offset, dst->sh_offset);
328 H_PUT_WORD (abfd, src->sh_size, dst->sh_size);
329 H_PUT_32 (abfd, src->sh_link, dst->sh_link);
330 H_PUT_32 (abfd, src->sh_info, dst->sh_info);
331 H_PUT_WORD (abfd, src->sh_addralign, dst->sh_addralign);
332 H_PUT_WORD (abfd, src->sh_entsize, dst->sh_entsize);
335 /* Translate an ELF program header table entry in external format into an
336 ELF program header table entry in internal format. */
338 void
339 elf_swap_phdr_in (bfd *abfd,
340 const Elf_External_Phdr *src,
341 Elf_Internal_Phdr *dst)
343 int signed_vma = get_elf_backend_data (abfd)->sign_extend_vma;
345 dst->p_type = H_GET_32 (abfd, src->p_type);
346 dst->p_flags = H_GET_32 (abfd, src->p_flags);
347 dst->p_offset = H_GET_WORD (abfd, src->p_offset);
348 if (signed_vma)
350 dst->p_vaddr = H_GET_SIGNED_WORD (abfd, src->p_vaddr);
351 dst->p_paddr = H_GET_SIGNED_WORD (abfd, src->p_paddr);
353 else
355 dst->p_vaddr = H_GET_WORD (abfd, src->p_vaddr);
356 dst->p_paddr = H_GET_WORD (abfd, src->p_paddr);
358 dst->p_filesz = H_GET_WORD (abfd, src->p_filesz);
359 dst->p_memsz = H_GET_WORD (abfd, src->p_memsz);
360 dst->p_align = H_GET_WORD (abfd, src->p_align);
363 void
364 elf_swap_phdr_out (bfd *abfd,
365 const Elf_Internal_Phdr *src,
366 Elf_External_Phdr *dst)
368 /* note that all elements of dst are *arrays of unsigned char* already... */
369 H_PUT_32 (abfd, src->p_type, dst->p_type);
370 H_PUT_WORD (abfd, src->p_offset, dst->p_offset);
371 H_PUT_WORD (abfd, src->p_vaddr, dst->p_vaddr);
372 H_PUT_WORD (abfd, src->p_paddr, dst->p_paddr);
373 H_PUT_WORD (abfd, src->p_filesz, dst->p_filesz);
374 H_PUT_WORD (abfd, src->p_memsz, dst->p_memsz);
375 H_PUT_32 (abfd, src->p_flags, dst->p_flags);
376 H_PUT_WORD (abfd, src->p_align, dst->p_align);
379 /* Translate an ELF reloc from external format to internal format. */
380 void
381 elf_swap_reloc_in (bfd *abfd,
382 const bfd_byte *s,
383 Elf_Internal_Rela *dst)
385 const Elf_External_Rel *src = (const Elf_External_Rel *) s;
386 dst->r_offset = H_GET_WORD (abfd, src->r_offset);
387 dst->r_info = H_GET_WORD (abfd, src->r_info);
388 dst->r_addend = 0;
391 void
392 elf_swap_reloca_in (bfd *abfd,
393 const bfd_byte *s,
394 Elf_Internal_Rela *dst)
396 const Elf_External_Rela *src = (const Elf_External_Rela *) s;
397 dst->r_offset = H_GET_WORD (abfd, src->r_offset);
398 dst->r_info = H_GET_WORD (abfd, src->r_info);
399 dst->r_addend = H_GET_SIGNED_WORD (abfd, src->r_addend);
402 /* Translate an ELF reloc from internal format to external format. */
403 void
404 elf_swap_reloc_out (bfd *abfd,
405 const Elf_Internal_Rela *src,
406 bfd_byte *d)
408 Elf_External_Rel *dst = (Elf_External_Rel *) d;
409 H_PUT_WORD (abfd, src->r_offset, dst->r_offset);
410 H_PUT_WORD (abfd, src->r_info, dst->r_info);
413 void
414 elf_swap_reloca_out (bfd *abfd,
415 const Elf_Internal_Rela *src,
416 bfd_byte *d)
418 Elf_External_Rela *dst = (Elf_External_Rela *) d;
419 H_PUT_WORD (abfd, src->r_offset, dst->r_offset);
420 H_PUT_WORD (abfd, src->r_info, dst->r_info);
421 H_PUT_SIGNED_WORD (abfd, src->r_addend, dst->r_addend);
424 void
425 elf_swap_dyn_in (bfd *abfd,
426 const void *p,
427 Elf_Internal_Dyn *dst)
429 const Elf_External_Dyn *src = p;
431 dst->d_tag = H_GET_WORD (abfd, src->d_tag);
432 dst->d_un.d_val = H_GET_WORD (abfd, src->d_un.d_val);
435 void
436 elf_swap_dyn_out (bfd *abfd,
437 const Elf_Internal_Dyn *src,
438 void *p)
440 Elf_External_Dyn *dst = p;
442 H_PUT_WORD (abfd, src->d_tag, dst->d_tag);
443 H_PUT_WORD (abfd, src->d_un.d_val, dst->d_un.d_val);
446 /* ELF .o/exec file reading */
448 /* Begin processing a given object.
450 First we validate the file by reading in the ELF header and checking
451 the magic number. */
453 static inline bfd_boolean
454 elf_file_p (Elf_External_Ehdr *x_ehdrp)
456 return ((x_ehdrp->e_ident[EI_MAG0] == ELFMAG0)
457 && (x_ehdrp->e_ident[EI_MAG1] == ELFMAG1)
458 && (x_ehdrp->e_ident[EI_MAG2] == ELFMAG2)
459 && (x_ehdrp->e_ident[EI_MAG3] == ELFMAG3));
462 /* Determines if a given section index is valid. */
464 static inline bfd_boolean
465 valid_section_index_p (unsigned index, unsigned num_sections)
467 /* Note: We allow SHN_UNDEF as a valid section index. */
468 if (index < SHN_LORESERVE || index > SHN_HIRESERVE)
469 return index < num_sections;
471 /* We disallow the use of reserved indcies, except for those
472 with OS or Application specific meaning. The test make use
473 of the knowledge that:
474 SHN_LORESERVE == SHN_LOPROC
476 SHN_HIPROC == SHN_LOOS - 1 */
477 /* XXX - Should we allow SHN_XINDEX as a valid index here ? */
478 return (index >= SHN_LOPROC && index <= SHN_HIOS);
481 /* Check to see if the file associated with ABFD matches the target vector
482 that ABFD points to.
484 Note that we may be called several times with the same ABFD, but different
485 target vectors, most of which will not match. We have to avoid leaving
486 any side effects in ABFD, or any data it points to (like tdata), if the
487 file does not match the target vector. */
489 const bfd_target *
490 elf_object_p (bfd *abfd)
492 Elf_External_Ehdr x_ehdr; /* Elf file header, external form */
493 Elf_Internal_Ehdr *i_ehdrp; /* Elf file header, internal form */
494 Elf_External_Shdr x_shdr; /* Section header table entry, external form */
495 Elf_Internal_Shdr i_shdr;
496 Elf_Internal_Shdr *i_shdrp; /* Section header table, internal form */
497 unsigned int shindex;
498 const struct elf_backend_data *ebd;
499 struct bfd_preserve preserve;
500 asection *s;
501 bfd_size_type amt;
503 preserve.marker = NULL;
505 /* Read in the ELF header in external format. */
507 if (bfd_bread (&x_ehdr, sizeof (x_ehdr), abfd) != sizeof (x_ehdr))
509 if (bfd_get_error () != bfd_error_system_call)
510 goto got_wrong_format_error;
511 else
512 goto got_no_match;
515 /* Now check to see if we have a valid ELF file, and one that BFD can
516 make use of. The magic number must match, the address size ('class')
517 and byte-swapping must match our XVEC entry, and it must have a
518 section header table (FIXME: See comments re sections at top of this
519 file). */
521 if (! elf_file_p (&x_ehdr)
522 || x_ehdr.e_ident[EI_VERSION] != EV_CURRENT
523 || x_ehdr.e_ident[EI_CLASS] != ELFCLASS)
524 goto got_wrong_format_error;
526 /* Check that file's byte order matches xvec's */
527 switch (x_ehdr.e_ident[EI_DATA])
529 case ELFDATA2MSB: /* Big-endian */
530 if (! bfd_header_big_endian (abfd))
531 goto got_wrong_format_error;
532 break;
533 case ELFDATA2LSB: /* Little-endian */
534 if (! bfd_header_little_endian (abfd))
535 goto got_wrong_format_error;
536 break;
537 case ELFDATANONE: /* No data encoding specified */
538 default: /* Unknown data encoding specified */
539 goto got_wrong_format_error;
542 if (!bfd_preserve_save (abfd, &preserve))
543 goto got_no_match;
545 /* Allocate an instance of the elf_obj_tdata structure and hook it up to
546 the tdata pointer in the bfd. */
548 if (! (*abfd->xvec->_bfd_set_format[bfd_object]) (abfd))
549 goto got_no_match;
550 preserve.marker = elf_tdata (abfd);
552 /* Now that we know the byte order, swap in the rest of the header */
553 i_ehdrp = elf_elfheader (abfd);
554 elf_swap_ehdr_in (abfd, &x_ehdr, i_ehdrp);
555 #if DEBUG & 1
556 elf_debug_file (i_ehdrp);
557 #endif
559 /* Reject ET_CORE (header indicates core file, not object file) */
560 if (i_ehdrp->e_type == ET_CORE)
561 goto got_wrong_format_error;
563 /* If this is a relocatable file and there is no section header
564 table, then we're hosed. */
565 if (i_ehdrp->e_shoff == 0 && i_ehdrp->e_type == ET_REL)
566 goto got_wrong_format_error;
568 /* As a simple sanity check, verify that what BFD thinks is the
569 size of each section header table entry actually matches the size
570 recorded in the file, but only if there are any sections. */
571 if (i_ehdrp->e_shentsize != sizeof (x_shdr) && i_ehdrp->e_shnum != 0)
572 goto got_wrong_format_error;
574 /* Further sanity check. */
575 if (i_ehdrp->e_shoff == 0 && i_ehdrp->e_shnum != 0)
576 goto got_wrong_format_error;
578 ebd = get_elf_backend_data (abfd);
580 /* Check that the ELF e_machine field matches what this particular
581 BFD format expects. */
582 if (ebd->elf_machine_code != i_ehdrp->e_machine
583 && (ebd->elf_machine_alt1 == 0
584 || i_ehdrp->e_machine != ebd->elf_machine_alt1)
585 && (ebd->elf_machine_alt2 == 0
586 || i_ehdrp->e_machine != ebd->elf_machine_alt2))
588 const bfd_target * const *target_ptr;
590 if (ebd->elf_machine_code != EM_NONE)
591 goto got_wrong_format_error;
593 /* This is the generic ELF target. Let it match any ELF target
594 for which we do not have a specific backend. */
595 for (target_ptr = bfd_target_vector; *target_ptr != NULL; target_ptr++)
597 const struct elf_backend_data *back;
599 if ((*target_ptr)->flavour != bfd_target_elf_flavour)
600 continue;
601 back = (const struct elf_backend_data *) (*target_ptr)->backend_data;
602 if (back->elf_machine_code == i_ehdrp->e_machine
603 || (back->elf_machine_alt1 != 0
604 && back->elf_machine_alt1 == i_ehdrp->e_machine)
605 || (back->elf_machine_alt2 != 0
606 && back->elf_machine_alt2 == i_ehdrp->e_machine))
608 /* target_ptr is an ELF backend which matches this
609 object file, so reject the generic ELF target. */
610 goto got_wrong_format_error;
615 if (i_ehdrp->e_type == ET_EXEC)
616 abfd->flags |= EXEC_P;
617 else if (i_ehdrp->e_type == ET_DYN)
618 abfd->flags |= DYNAMIC;
620 if (i_ehdrp->e_phnum > 0)
621 abfd->flags |= D_PAGED;
623 if (! bfd_default_set_arch_mach (abfd, ebd->arch, 0))
625 /* It's OK if this fails for the generic target. */
626 if (ebd->elf_machine_code != EM_NONE)
627 goto got_no_match;
630 if (i_ehdrp->e_shoff != 0)
632 bfd_signed_vma where = i_ehdrp->e_shoff;
634 if (where != (file_ptr) where)
635 goto got_wrong_format_error;
637 /* Seek to the section header table in the file. */
638 if (bfd_seek (abfd, (file_ptr) where, SEEK_SET) != 0)
639 goto got_no_match;
641 /* Read the first section header at index 0, and convert to internal
642 form. */
643 if (bfd_bread (&x_shdr, sizeof x_shdr, abfd) != sizeof (x_shdr))
644 goto got_no_match;
645 elf_swap_shdr_in (abfd, &x_shdr, &i_shdr);
647 /* If the section count is zero, the actual count is in the first
648 section header. */
649 if (i_ehdrp->e_shnum == SHN_UNDEF)
651 i_ehdrp->e_shnum = i_shdr.sh_size;
652 if (i_ehdrp->e_shnum != i_shdr.sh_size
653 || i_ehdrp->e_shnum == 0)
654 goto got_wrong_format_error;
657 /* And similarly for the string table index. */
658 if (i_ehdrp->e_shstrndx == SHN_XINDEX)
660 i_ehdrp->e_shstrndx = i_shdr.sh_link;
661 if (i_ehdrp->e_shstrndx != i_shdr.sh_link)
662 goto got_wrong_format_error;
665 /* Sanity check that we can read all of the section headers.
666 It ought to be good enough to just read the last one. */
667 if (i_ehdrp->e_shnum != 1)
669 /* Check that we don't have a totally silly number of sections. */
670 if (i_ehdrp->e_shnum > (unsigned int) -1 / sizeof (x_shdr)
671 || i_ehdrp->e_shnum > (unsigned int) -1 / sizeof (i_shdr))
672 goto got_wrong_format_error;
674 where += (i_ehdrp->e_shnum - 1) * sizeof (x_shdr);
675 if (where != (file_ptr) where)
676 goto got_wrong_format_error;
677 if ((bfd_size_type) where <= i_ehdrp->e_shoff)
678 goto got_wrong_format_error;
680 if (bfd_seek (abfd, (file_ptr) where, SEEK_SET) != 0)
681 goto got_no_match;
682 if (bfd_bread (&x_shdr, sizeof x_shdr, abfd) != sizeof (x_shdr))
683 goto got_no_match;
685 /* Back to where we were. */
686 where = i_ehdrp->e_shoff + sizeof (x_shdr);
687 if (bfd_seek (abfd, (file_ptr) where, SEEK_SET) != 0)
688 goto got_no_match;
692 /* Allocate space for a copy of the section header table in
693 internal form. */
694 if (i_ehdrp->e_shnum != 0)
696 Elf_Internal_Shdr *shdrp;
697 unsigned int num_sec;
699 amt = sizeof (*i_shdrp) * i_ehdrp->e_shnum;
700 i_shdrp = bfd_alloc (abfd, amt);
701 if (!i_shdrp)
702 goto got_no_match;
703 num_sec = i_ehdrp->e_shnum;
704 if (num_sec > SHN_LORESERVE)
705 num_sec += SHN_HIRESERVE + 1 - SHN_LORESERVE;
706 elf_numsections (abfd) = num_sec;
707 amt = sizeof (i_shdrp) * num_sec;
708 elf_elfsections (abfd) = bfd_alloc (abfd, amt);
709 if (!elf_elfsections (abfd))
710 goto got_no_match;
712 memcpy (i_shdrp, &i_shdr, sizeof (*i_shdrp));
713 shdrp = i_shdrp;
714 shindex = 0;
715 if (num_sec > SHN_LORESERVE)
717 for ( ; shindex < SHN_LORESERVE; shindex++)
718 elf_elfsections (abfd)[shindex] = shdrp++;
719 for ( ; shindex < SHN_HIRESERVE + 1; shindex++)
720 elf_elfsections (abfd)[shindex] = i_shdrp;
722 for ( ; shindex < num_sec; shindex++)
723 elf_elfsections (abfd)[shindex] = shdrp++;
725 /* Read in the rest of the section header table and convert it
726 to internal form. */
727 for (shindex = 1; shindex < i_ehdrp->e_shnum; shindex++)
729 if (bfd_bread (&x_shdr, sizeof x_shdr, abfd) != sizeof (x_shdr))
730 goto got_no_match;
731 elf_swap_shdr_in (abfd, &x_shdr, i_shdrp + shindex);
733 /* Sanity check sh_link and sh_info. */
734 if (! valid_section_index_p (i_shdrp[shindex].sh_link, num_sec))
735 goto got_wrong_format_error;
737 if (((i_shdrp[shindex].sh_flags & SHF_INFO_LINK)
738 || i_shdrp[shindex].sh_type == SHT_RELA
739 || i_shdrp[shindex].sh_type == SHT_REL)
740 && ! valid_section_index_p (i_shdrp[shindex].sh_info, num_sec))
741 goto got_wrong_format_error;
743 /* If the section is loaded, but not page aligned, clear
744 D_PAGED. */
745 if (i_shdrp[shindex].sh_size != 0
746 && (i_shdrp[shindex].sh_flags & SHF_ALLOC) != 0
747 && i_shdrp[shindex].sh_type != SHT_NOBITS
748 && (((i_shdrp[shindex].sh_addr - i_shdrp[shindex].sh_offset)
749 % ebd->minpagesize)
750 != 0))
751 abfd->flags &= ~D_PAGED;
755 /* A further sanity check. */
756 if (i_ehdrp->e_shnum != 0)
758 if (! valid_section_index_p (i_ehdrp->e_shstrndx, elf_numsections (abfd)))
760 /* PR 2257:
761 We used to just goto got_wrong_format_error here
762 but there are binaries in existance for which this test
763 will prevent the binutils from working with them at all.
764 So we are kind, and reset the string index value to 0
765 so that at least some processing can be done. */
766 i_ehdrp->e_shstrndx = SHN_UNDEF;
767 _bfd_error_handler (_("warning: %s has a corrupt string table index - ignoring"), abfd->filename);
770 else if (i_ehdrp->e_shstrndx != SHN_UNDEF)
771 goto got_wrong_format_error;
773 /* Read in the program headers. */
774 if (i_ehdrp->e_phnum == 0)
775 elf_tdata (abfd)->phdr = NULL;
776 else
778 Elf_Internal_Phdr *i_phdr;
779 unsigned int i;
781 amt = i_ehdrp->e_phnum * sizeof (Elf_Internal_Phdr);
782 elf_tdata (abfd)->phdr = bfd_alloc (abfd, amt);
783 if (elf_tdata (abfd)->phdr == NULL)
784 goto got_no_match;
785 if (bfd_seek (abfd, (file_ptr) i_ehdrp->e_phoff, SEEK_SET) != 0)
786 goto got_no_match;
787 i_phdr = elf_tdata (abfd)->phdr;
788 for (i = 0; i < i_ehdrp->e_phnum; i++, i_phdr++)
790 Elf_External_Phdr x_phdr;
792 if (bfd_bread (&x_phdr, sizeof x_phdr, abfd) != sizeof x_phdr)
793 goto got_no_match;
794 elf_swap_phdr_in (abfd, &x_phdr, i_phdr);
798 if (i_ehdrp->e_shstrndx != 0 && i_ehdrp->e_shoff != 0)
800 unsigned int num_sec;
802 /* Once all of the section headers have been read and converted, we
803 can start processing them. Note that the first section header is
804 a dummy placeholder entry, so we ignore it. */
805 num_sec = elf_numsections (abfd);
806 for (shindex = 1; shindex < num_sec; shindex++)
808 if (! bfd_section_from_shdr (abfd, shindex))
809 goto got_no_match;
810 if (shindex == SHN_LORESERVE - 1)
811 shindex += SHN_HIRESERVE + 1 - SHN_LORESERVE;
814 /* Set up ELF sections for SHF_GROUP and SHF_LINK_ORDER. */
815 if (! _bfd_elf_setup_sections (abfd))
816 goto got_wrong_format_error;
819 /* Let the backend double check the format and override global
820 information. */
821 if (ebd->elf_backend_object_p)
823 if (! (*ebd->elf_backend_object_p) (abfd))
824 goto got_wrong_format_error;
827 /* Remember the entry point specified in the ELF file header. */
828 bfd_set_start_address (abfd, i_ehdrp->e_entry);
830 /* If we have created any reloc sections that are associated with
831 debugging sections, mark the reloc sections as debugging as well. */
832 for (s = abfd->sections; s != NULL; s = s->next)
834 if ((elf_section_data (s)->this_hdr.sh_type == SHT_REL
835 || elf_section_data (s)->this_hdr.sh_type == SHT_RELA)
836 && elf_section_data (s)->this_hdr.sh_info > 0)
838 unsigned long targ_index;
839 asection *targ_sec;
841 targ_index = elf_section_data (s)->this_hdr.sh_info;
842 targ_sec = bfd_section_from_elf_index (abfd, targ_index);
843 if (targ_sec != NULL
844 && (targ_sec->flags & SEC_DEBUGGING) != 0)
845 s->flags |= SEC_DEBUGGING;
849 bfd_preserve_finish (abfd, &preserve);
850 return abfd->xvec;
852 got_wrong_format_error:
853 /* There is way too much undoing of half-known state here. The caller,
854 bfd_check_format_matches, really shouldn't iterate on live bfd's to
855 check match/no-match like it does. We have to rely on that a call to
856 bfd_default_set_arch_mach with the previously known mach, undoes what
857 was done by the first bfd_default_set_arch_mach (with mach 0) here.
858 For this to work, only elf-data and the mach may be changed by the
859 target-specific elf_backend_object_p function. Note that saving the
860 whole bfd here and restoring it would be even worse; the first thing
861 you notice is that the cached bfd file position gets out of sync. */
862 bfd_set_error (bfd_error_wrong_format);
864 got_no_match:
865 if (preserve.marker != NULL)
866 bfd_preserve_restore (abfd, &preserve);
867 return NULL;
870 /* ELF .o/exec file writing */
872 /* Write out the relocs. */
874 void
875 elf_write_relocs (bfd *abfd, asection *sec, void *data)
877 bfd_boolean *failedp = data;
878 Elf_Internal_Shdr *rela_hdr;
879 bfd_vma addr_offset;
880 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
881 size_t extsize;
882 bfd_byte *dst_rela;
883 unsigned int idx;
884 asymbol *last_sym;
885 int last_sym_idx;
887 /* If we have already failed, don't do anything. */
888 if (*failedp)
889 return;
891 if ((sec->flags & SEC_RELOC) == 0)
892 return;
894 /* The linker backend writes the relocs out itself, and sets the
895 reloc_count field to zero to inhibit writing them here. Also,
896 sometimes the SEC_RELOC flag gets set even when there aren't any
897 relocs. */
898 if (sec->reloc_count == 0)
899 return;
901 /* If we have opened an existing file for update, reloc_count may be
902 set even though we are not linking. In that case we have nothing
903 to do. */
904 if (sec->orelocation == NULL)
905 return;
907 rela_hdr = &elf_section_data (sec)->rel_hdr;
909 rela_hdr->sh_size = rela_hdr->sh_entsize * sec->reloc_count;
910 rela_hdr->contents = bfd_alloc (abfd, rela_hdr->sh_size);
911 if (rela_hdr->contents == NULL)
913 *failedp = TRUE;
914 return;
917 /* Figure out whether the relocations are RELA or REL relocations. */
918 if (rela_hdr->sh_type == SHT_RELA)
920 swap_out = elf_swap_reloca_out;
921 extsize = sizeof (Elf_External_Rela);
923 else if (rela_hdr->sh_type == SHT_REL)
925 swap_out = elf_swap_reloc_out;
926 extsize = sizeof (Elf_External_Rel);
928 else
929 /* Every relocation section should be either an SHT_RELA or an
930 SHT_REL section. */
931 abort ();
933 /* The address of an ELF reloc is section relative for an object
934 file, and absolute for an executable file or shared library.
935 The address of a BFD reloc is always section relative. */
936 addr_offset = 0;
937 if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
938 addr_offset = sec->vma;
940 /* orelocation has the data, reloc_count has the count... */
941 last_sym = 0;
942 last_sym_idx = 0;
943 dst_rela = rela_hdr->contents;
945 for (idx = 0; idx < sec->reloc_count; idx++, dst_rela += extsize)
947 Elf_Internal_Rela src_rela;
948 arelent *ptr;
949 asymbol *sym;
950 int n;
952 ptr = sec->orelocation[idx];
953 sym = *ptr->sym_ptr_ptr;
954 if (sym == last_sym)
955 n = last_sym_idx;
956 else if (bfd_is_abs_section (sym->section) && sym->value == 0)
957 n = STN_UNDEF;
958 else
960 last_sym = sym;
961 n = _bfd_elf_symbol_from_bfd_symbol (abfd, &sym);
962 if (n < 0)
964 *failedp = TRUE;
965 return;
967 last_sym_idx = n;
970 if ((*ptr->sym_ptr_ptr)->the_bfd != NULL
971 && (*ptr->sym_ptr_ptr)->the_bfd->xvec != abfd->xvec
972 && ! _bfd_elf_validate_reloc (abfd, ptr))
974 *failedp = TRUE;
975 return;
978 src_rela.r_offset = ptr->address + addr_offset;
979 src_rela.r_info = ELF_R_INFO (n, ptr->howto->type);
980 src_rela.r_addend = ptr->addend;
981 (*swap_out) (abfd, &src_rela, dst_rela);
985 /* Write out the program headers. */
988 elf_write_out_phdrs (bfd *abfd,
989 const Elf_Internal_Phdr *phdr,
990 unsigned int count)
992 while (count--)
994 Elf_External_Phdr extphdr;
995 elf_swap_phdr_out (abfd, phdr, &extphdr);
996 if (bfd_bwrite (&extphdr, sizeof (Elf_External_Phdr), abfd)
997 != sizeof (Elf_External_Phdr))
998 return -1;
999 phdr++;
1001 return 0;
1004 /* Write out the section headers and the ELF file header. */
1006 bfd_boolean
1007 elf_write_shdrs_and_ehdr (bfd *abfd)
1009 Elf_External_Ehdr x_ehdr; /* Elf file header, external form */
1010 Elf_Internal_Ehdr *i_ehdrp; /* Elf file header, internal form */
1011 Elf_External_Shdr *x_shdrp; /* Section header table, external form */
1012 Elf_Internal_Shdr **i_shdrp; /* Section header table, internal form */
1013 unsigned int count;
1014 bfd_size_type amt;
1016 i_ehdrp = elf_elfheader (abfd);
1017 i_shdrp = elf_elfsections (abfd);
1019 /* swap the header before spitting it out... */
1021 #if DEBUG & 1
1022 elf_debug_file (i_ehdrp);
1023 #endif
1024 elf_swap_ehdr_out (abfd, i_ehdrp, &x_ehdr);
1025 amt = sizeof (x_ehdr);
1026 if (bfd_seek (abfd, (file_ptr) 0, SEEK_SET) != 0
1027 || bfd_bwrite (&x_ehdr, amt, abfd) != amt)
1028 return FALSE;
1030 /* Some fields in the first section header handle overflow of ehdr
1031 fields. */
1032 if (i_ehdrp->e_shnum >= SHN_LORESERVE)
1033 i_shdrp[0]->sh_size = i_ehdrp->e_shnum;
1034 if (i_ehdrp->e_shstrndx >= SHN_LORESERVE)
1035 i_shdrp[0]->sh_link = i_ehdrp->e_shstrndx;
1037 /* at this point we've concocted all the ELF sections... */
1038 amt = i_ehdrp->e_shnum;
1039 amt *= sizeof (*x_shdrp);
1040 x_shdrp = bfd_alloc (abfd, amt);
1041 if (!x_shdrp)
1042 return FALSE;
1044 for (count = 0; count < i_ehdrp->e_shnum; i_shdrp++, count++)
1046 #if DEBUG & 2
1047 elf_debug_section (count, *i_shdrp);
1048 #endif
1049 elf_swap_shdr_out (abfd, *i_shdrp, x_shdrp + count);
1051 if (count == SHN_LORESERVE - 1)
1052 i_shdrp += SHN_HIRESERVE + 1 - SHN_LORESERVE;
1054 if (bfd_seek (abfd, (file_ptr) i_ehdrp->e_shoff, SEEK_SET) != 0
1055 || bfd_bwrite (x_shdrp, amt, abfd) != amt)
1056 return FALSE;
1058 /* need to dump the string table too... */
1060 return TRUE;
1063 long
1064 elf_slurp_symbol_table (bfd *abfd, asymbol **symptrs, bfd_boolean dynamic)
1066 Elf_Internal_Shdr *hdr;
1067 Elf_Internal_Shdr *verhdr;
1068 unsigned long symcount; /* Number of external ELF symbols */
1069 elf_symbol_type *sym; /* Pointer to current bfd symbol */
1070 elf_symbol_type *symbase; /* Buffer for generated bfd symbols */
1071 Elf_Internal_Sym *isym;
1072 Elf_Internal_Sym *isymend;
1073 Elf_Internal_Sym *isymbuf = NULL;
1074 Elf_External_Versym *xver;
1075 Elf_External_Versym *xverbuf = NULL;
1076 const struct elf_backend_data *ebd;
1077 bfd_size_type amt;
1079 /* Read each raw ELF symbol, converting from external ELF form to
1080 internal ELF form, and then using the information to create a
1081 canonical bfd symbol table entry.
1083 Note that we allocate the initial bfd canonical symbol buffer
1084 based on a one-to-one mapping of the ELF symbols to canonical
1085 symbols. We actually use all the ELF symbols, so there will be no
1086 space left over at the end. When we have all the symbols, we
1087 build the caller's pointer vector. */
1089 if (! dynamic)
1091 hdr = &elf_tdata (abfd)->symtab_hdr;
1092 verhdr = NULL;
1094 else
1096 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
1097 if (elf_dynversym (abfd) == 0)
1098 verhdr = NULL;
1099 else
1100 verhdr = &elf_tdata (abfd)->dynversym_hdr;
1101 if ((elf_tdata (abfd)->dynverdef_section != 0
1102 && elf_tdata (abfd)->verdef == NULL)
1103 || (elf_tdata (abfd)->dynverref_section != 0
1104 && elf_tdata (abfd)->verref == NULL))
1106 if (!_bfd_elf_slurp_version_tables (abfd, FALSE))
1107 return -1;
1111 ebd = get_elf_backend_data (abfd);
1112 symcount = hdr->sh_size / sizeof (Elf_External_Sym);
1113 if (symcount == 0)
1114 sym = symbase = NULL;
1115 else
1117 isymbuf = bfd_elf_get_elf_syms (abfd, hdr, symcount, 0,
1118 NULL, NULL, NULL);
1119 if (isymbuf == NULL)
1120 return -1;
1122 amt = symcount;
1123 amt *= sizeof (elf_symbol_type);
1124 symbase = bfd_zalloc (abfd, amt);
1125 if (symbase == (elf_symbol_type *) NULL)
1126 goto error_return;
1128 /* Read the raw ELF version symbol information. */
1129 if (verhdr != NULL
1130 && verhdr->sh_size / sizeof (Elf_External_Versym) != symcount)
1132 (*_bfd_error_handler)
1133 (_("%s: version count (%ld) does not match symbol count (%ld)"),
1134 abfd->filename,
1135 (long) (verhdr->sh_size / sizeof (Elf_External_Versym)),
1136 symcount);
1138 /* Slurp in the symbols without the version information,
1139 since that is more helpful than just quitting. */
1140 verhdr = NULL;
1143 if (verhdr != NULL)
1145 if (bfd_seek (abfd, verhdr->sh_offset, SEEK_SET) != 0)
1146 goto error_return;
1148 xverbuf = bfd_malloc (verhdr->sh_size);
1149 if (xverbuf == NULL && verhdr->sh_size != 0)
1150 goto error_return;
1152 if (bfd_bread (xverbuf, verhdr->sh_size, abfd) != verhdr->sh_size)
1153 goto error_return;
1156 /* Skip first symbol, which is a null dummy. */
1157 xver = xverbuf;
1158 if (xver != NULL)
1159 ++xver;
1160 isymend = isymbuf + symcount;
1161 for (isym = isymbuf + 1, sym = symbase; isym < isymend; isym++, sym++)
1163 memcpy (&sym->internal_elf_sym, isym, sizeof (Elf_Internal_Sym));
1164 sym->symbol.the_bfd = abfd;
1166 sym->symbol.name = bfd_elf_sym_name (abfd, hdr, isym, NULL);
1168 sym->symbol.value = isym->st_value;
1170 if (isym->st_shndx == SHN_UNDEF)
1172 sym->symbol.section = bfd_und_section_ptr;
1174 else if (isym->st_shndx < SHN_LORESERVE
1175 || isym->st_shndx > SHN_HIRESERVE)
1177 sym->symbol.section = bfd_section_from_elf_index (abfd,
1178 isym->st_shndx);
1179 if (sym->symbol.section == NULL)
1181 /* This symbol is in a section for which we did not
1182 create a BFD section. Just use bfd_abs_section,
1183 although it is wrong. FIXME. */
1184 sym->symbol.section = bfd_abs_section_ptr;
1187 else if (isym->st_shndx == SHN_ABS)
1189 sym->symbol.section = bfd_abs_section_ptr;
1191 else if (isym->st_shndx == SHN_COMMON)
1193 sym->symbol.section = bfd_com_section_ptr;
1194 /* Elf puts the alignment into the `value' field, and
1195 the size into the `size' field. BFD wants to see the
1196 size in the value field, and doesn't care (at the
1197 moment) about the alignment. */
1198 sym->symbol.value = isym->st_size;
1200 else
1201 sym->symbol.section = bfd_abs_section_ptr;
1203 /* If this is a relocatable file, then the symbol value is
1204 already section relative. */
1205 if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
1206 sym->symbol.value -= sym->symbol.section->vma;
1208 switch (ELF_ST_BIND (isym->st_info))
1210 case STB_LOCAL:
1211 sym->symbol.flags |= BSF_LOCAL;
1212 break;
1213 case STB_GLOBAL:
1214 if (isym->st_shndx != SHN_UNDEF && isym->st_shndx != SHN_COMMON)
1215 sym->symbol.flags |= BSF_GLOBAL;
1216 break;
1217 case STB_WEAK:
1218 sym->symbol.flags |= BSF_WEAK;
1219 break;
1222 switch (ELF_ST_TYPE (isym->st_info))
1224 case STT_SECTION:
1225 sym->symbol.flags |= BSF_SECTION_SYM | BSF_DEBUGGING;
1226 break;
1227 case STT_FILE:
1228 sym->symbol.flags |= BSF_FILE | BSF_DEBUGGING;
1229 break;
1230 case STT_FUNC:
1231 sym->symbol.flags |= BSF_FUNCTION;
1232 break;
1233 case STT_OBJECT:
1234 sym->symbol.flags |= BSF_OBJECT;
1235 break;
1236 case STT_TLS:
1237 sym->symbol.flags |= BSF_THREAD_LOCAL;
1238 break;
1241 if (dynamic)
1242 sym->symbol.flags |= BSF_DYNAMIC;
1244 if (xver != NULL)
1246 Elf_Internal_Versym iversym;
1248 _bfd_elf_swap_versym_in (abfd, xver, &iversym);
1249 sym->version = iversym.vs_vers;
1250 xver++;
1253 /* Do some backend-specific processing on this symbol. */
1254 if (ebd->elf_backend_symbol_processing)
1255 (*ebd->elf_backend_symbol_processing) (abfd, &sym->symbol);
1259 /* Do some backend-specific processing on this symbol table. */
1260 if (ebd->elf_backend_symbol_table_processing)
1261 (*ebd->elf_backend_symbol_table_processing) (abfd, symbase, symcount);
1263 /* We rely on the zalloc to clear out the final symbol entry. */
1265 symcount = sym - symbase;
1267 /* Fill in the user's symbol pointer vector if needed. */
1268 if (symptrs)
1270 long l = symcount;
1272 sym = symbase;
1273 while (l-- > 0)
1275 *symptrs++ = &sym->symbol;
1276 sym++;
1278 *symptrs = 0; /* Final null pointer */
1281 if (xverbuf != NULL)
1282 free (xverbuf);
1283 if (isymbuf != NULL && hdr->contents != (unsigned char *) isymbuf)
1284 free (isymbuf);
1285 return symcount;
1287 error_return:
1288 if (xverbuf != NULL)
1289 free (xverbuf);
1290 if (isymbuf != NULL && hdr->contents != (unsigned char *) isymbuf)
1291 free (isymbuf);
1292 return -1;
1295 /* Read relocations for ASECT from REL_HDR. There are RELOC_COUNT of
1296 them. */
1298 static bfd_boolean
1299 elf_slurp_reloc_table_from_section (bfd *abfd,
1300 asection *asect,
1301 Elf_Internal_Shdr *rel_hdr,
1302 bfd_size_type reloc_count,
1303 arelent *relents,
1304 asymbol **symbols,
1305 bfd_boolean dynamic)
1307 const struct elf_backend_data * const ebd = get_elf_backend_data (abfd);
1308 void *allocated = NULL;
1309 bfd_byte *native_relocs;
1310 arelent *relent;
1311 unsigned int i;
1312 int entsize;
1313 unsigned int symcount;
1315 allocated = bfd_malloc (rel_hdr->sh_size);
1316 if (allocated == NULL)
1317 goto error_return;
1319 if (bfd_seek (abfd, rel_hdr->sh_offset, SEEK_SET) != 0
1320 || (bfd_bread (allocated, rel_hdr->sh_size, abfd)
1321 != rel_hdr->sh_size))
1322 goto error_return;
1324 native_relocs = allocated;
1326 entsize = rel_hdr->sh_entsize;
1327 BFD_ASSERT (entsize == sizeof (Elf_External_Rel)
1328 || entsize == sizeof (Elf_External_Rela));
1330 if (dynamic)
1331 symcount = bfd_get_dynamic_symcount (abfd);
1332 else
1333 symcount = bfd_get_symcount (abfd);
1335 for (i = 0, relent = relents;
1336 i < reloc_count;
1337 i++, relent++, native_relocs += entsize)
1339 Elf_Internal_Rela rela;
1341 if (entsize == sizeof (Elf_External_Rela))
1342 elf_swap_reloca_in (abfd, native_relocs, &rela);
1343 else
1344 elf_swap_reloc_in (abfd, native_relocs, &rela);
1346 /* The address of an ELF reloc is section relative for an object
1347 file, and absolute for an executable file or shared library.
1348 The address of a normal BFD reloc is always section relative,
1349 and the address of a dynamic reloc is absolute.. */
1350 if ((abfd->flags & (EXEC_P | DYNAMIC)) == 0 || dynamic)
1351 relent->address = rela.r_offset;
1352 else
1353 relent->address = rela.r_offset - asect->vma;
1355 if (ELF_R_SYM (rela.r_info) == 0)
1356 relent->sym_ptr_ptr = bfd_abs_section_ptr->symbol_ptr_ptr;
1357 else if (ELF_R_SYM (rela.r_info) > symcount)
1359 (*_bfd_error_handler)
1360 (_("%s(%s): relocation %d has invalid symbol index %ld"),
1361 abfd->filename, asect->name, i, ELF_R_SYM (rela.r_info));
1362 relent->sym_ptr_ptr = bfd_abs_section.symbol_ptr_ptr;
1364 else
1366 asymbol **ps;
1368 ps = symbols + ELF_R_SYM (rela.r_info) - 1;
1370 relent->sym_ptr_ptr = ps;
1373 relent->addend = rela.r_addend;
1375 if ((entsize == sizeof (Elf_External_Rela)
1376 && ebd->elf_info_to_howto != NULL)
1377 || ebd->elf_info_to_howto_rel == NULL)
1378 (*ebd->elf_info_to_howto) (abfd, relent, &rela);
1379 else
1380 (*ebd->elf_info_to_howto_rel) (abfd, relent, &rela);
1383 if (allocated != NULL)
1384 free (allocated);
1386 return TRUE;
1388 error_return:
1389 if (allocated != NULL)
1390 free (allocated);
1391 return FALSE;
1394 /* Read in and swap the external relocs. */
1396 bfd_boolean
1397 elf_slurp_reloc_table (bfd *abfd,
1398 asection *asect,
1399 asymbol **symbols,
1400 bfd_boolean dynamic)
1402 struct bfd_elf_section_data * const d = elf_section_data (asect);
1403 Elf_Internal_Shdr *rel_hdr;
1404 Elf_Internal_Shdr *rel_hdr2;
1405 bfd_size_type reloc_count;
1406 bfd_size_type reloc_count2;
1407 arelent *relents;
1408 bfd_size_type amt;
1410 if (asect->relocation != NULL)
1411 return TRUE;
1413 if (! dynamic)
1415 if ((asect->flags & SEC_RELOC) == 0
1416 || asect->reloc_count == 0)
1417 return TRUE;
1419 rel_hdr = &d->rel_hdr;
1420 reloc_count = NUM_SHDR_ENTRIES (rel_hdr);
1421 rel_hdr2 = d->rel_hdr2;
1422 reloc_count2 = (rel_hdr2 ? NUM_SHDR_ENTRIES (rel_hdr2) : 0);
1424 BFD_ASSERT (asect->reloc_count == reloc_count + reloc_count2);
1425 BFD_ASSERT (asect->rel_filepos == rel_hdr->sh_offset
1426 || (rel_hdr2 && asect->rel_filepos == rel_hdr2->sh_offset));
1429 else
1431 /* Note that ASECT->RELOC_COUNT tends not to be accurate in this
1432 case because relocations against this section may use the
1433 dynamic symbol table, and in that case bfd_section_from_shdr
1434 in elf.c does not update the RELOC_COUNT. */
1435 if (asect->size == 0)
1436 return TRUE;
1438 rel_hdr = &d->this_hdr;
1439 reloc_count = NUM_SHDR_ENTRIES (rel_hdr);
1440 rel_hdr2 = NULL;
1441 reloc_count2 = 0;
1444 amt = (reloc_count + reloc_count2) * sizeof (arelent);
1445 relents = bfd_alloc (abfd, amt);
1446 if (relents == NULL)
1447 return FALSE;
1449 if (!elf_slurp_reloc_table_from_section (abfd, asect,
1450 rel_hdr, reloc_count,
1451 relents,
1452 symbols, dynamic))
1453 return FALSE;
1455 if (rel_hdr2
1456 && !elf_slurp_reloc_table_from_section (abfd, asect,
1457 rel_hdr2, reloc_count2,
1458 relents + reloc_count,
1459 symbols, dynamic))
1460 return FALSE;
1462 asect->relocation = relents;
1463 return TRUE;
1466 #if DEBUG & 2
1467 static void
1468 elf_debug_section (int num, Elf_Internal_Shdr *hdr)
1470 fprintf (stderr, "\nSection#%d '%s' 0x%.8lx\n", num,
1471 hdr->bfd_section != NULL ? hdr->bfd_section->name : "",
1472 (long) hdr);
1473 fprintf (stderr,
1474 "sh_name = %ld\tsh_type = %ld\tsh_flags = %ld\n",
1475 (long) hdr->sh_name,
1476 (long) hdr->sh_type,
1477 (long) hdr->sh_flags);
1478 fprintf (stderr,
1479 "sh_addr = %ld\tsh_offset = %ld\tsh_size = %ld\n",
1480 (long) hdr->sh_addr,
1481 (long) hdr->sh_offset,
1482 (long) hdr->sh_size);
1483 fprintf (stderr,
1484 "sh_link = %ld\tsh_info = %ld\tsh_addralign = %ld\n",
1485 (long) hdr->sh_link,
1486 (long) hdr->sh_info,
1487 (long) hdr->sh_addralign);
1488 fprintf (stderr, "sh_entsize = %ld\n",
1489 (long) hdr->sh_entsize);
1490 fflush (stderr);
1492 #endif
1494 #if DEBUG & 1
1495 static void
1496 elf_debug_file (Elf_Internal_Ehdr *ehdrp)
1498 fprintf (stderr, "e_entry = 0x%.8lx\n", (long) ehdrp->e_entry);
1499 fprintf (stderr, "e_phoff = %ld\n", (long) ehdrp->e_phoff);
1500 fprintf (stderr, "e_phnum = %ld\n", (long) ehdrp->e_phnum);
1501 fprintf (stderr, "e_phentsize = %ld\n", (long) ehdrp->e_phentsize);
1502 fprintf (stderr, "e_shoff = %ld\n", (long) ehdrp->e_shoff);
1503 fprintf (stderr, "e_shnum = %ld\n", (long) ehdrp->e_shnum);
1504 fprintf (stderr, "e_shentsize = %ld\n", (long) ehdrp->e_shentsize);
1506 #endif
1508 /* Create a new BFD as if by bfd_openr. Rather than opening a file,
1509 reconstruct an ELF file by reading the segments out of remote memory
1510 based on the ELF file header at EHDR_VMA and the ELF program headers it
1511 points to. If not null, *LOADBASEP is filled in with the difference
1512 between the VMAs from which the segments were read, and the VMAs the
1513 file headers (and hence BFD's idea of each section's VMA) put them at.
1515 The function TARGET_READ_MEMORY is called to copy LEN bytes from the
1516 remote memory at target address VMA into the local buffer at MYADDR; it
1517 should return zero on success or an `errno' code on failure. TEMPL must
1518 be a BFD for a target with the word size and byte order found in the
1519 remote memory. */
1521 bfd *
1522 NAME(_bfd_elf,bfd_from_remote_memory)
1523 (bfd *templ,
1524 bfd_vma ehdr_vma,
1525 bfd_vma *loadbasep,
1526 int (*target_read_memory) (bfd_vma, bfd_byte *, int))
1528 Elf_External_Ehdr x_ehdr; /* Elf file header, external form */
1529 Elf_Internal_Ehdr i_ehdr; /* Elf file header, internal form */
1530 Elf_External_Phdr *x_phdrs;
1531 Elf_Internal_Phdr *i_phdrs, *last_phdr;
1532 bfd *nbfd;
1533 struct bfd_in_memory *bim;
1534 int contents_size;
1535 bfd_byte *contents;
1536 int err;
1537 unsigned int i;
1538 bfd_vma loadbase;
1540 /* Read in the ELF header in external format. */
1541 err = target_read_memory (ehdr_vma, (bfd_byte *) &x_ehdr, sizeof x_ehdr);
1542 if (err)
1544 bfd_set_error (bfd_error_system_call);
1545 errno = err;
1546 return NULL;
1549 /* Now check to see if we have a valid ELF file, and one that BFD can
1550 make use of. The magic number must match, the address size ('class')
1551 and byte-swapping must match our XVEC entry. */
1553 if (! elf_file_p (&x_ehdr)
1554 || x_ehdr.e_ident[EI_VERSION] != EV_CURRENT
1555 || x_ehdr.e_ident[EI_CLASS] != ELFCLASS)
1557 bfd_set_error (bfd_error_wrong_format);
1558 return NULL;
1561 /* Check that file's byte order matches xvec's */
1562 switch (x_ehdr.e_ident[EI_DATA])
1564 case ELFDATA2MSB: /* Big-endian */
1565 if (! bfd_header_big_endian (templ))
1567 bfd_set_error (bfd_error_wrong_format);
1568 return NULL;
1570 break;
1571 case ELFDATA2LSB: /* Little-endian */
1572 if (! bfd_header_little_endian (templ))
1574 bfd_set_error (bfd_error_wrong_format);
1575 return NULL;
1577 break;
1578 case ELFDATANONE: /* No data encoding specified */
1579 default: /* Unknown data encoding specified */
1580 bfd_set_error (bfd_error_wrong_format);
1581 return NULL;
1584 elf_swap_ehdr_in (templ, &x_ehdr, &i_ehdr);
1586 /* The file header tells where to find the program headers.
1587 These are what we use to actually choose what to read. */
1589 if (i_ehdr.e_phentsize != sizeof (Elf_External_Phdr) || i_ehdr.e_phnum == 0)
1591 bfd_set_error (bfd_error_wrong_format);
1592 return NULL;
1595 x_phdrs = bfd_malloc (i_ehdr.e_phnum * (sizeof *x_phdrs + sizeof *i_phdrs));
1596 if (x_phdrs == NULL)
1598 bfd_set_error (bfd_error_no_memory);
1599 return NULL;
1601 err = target_read_memory (ehdr_vma + i_ehdr.e_phoff, (bfd_byte *) x_phdrs,
1602 i_ehdr.e_phnum * sizeof x_phdrs[0]);
1603 if (err)
1605 free (x_phdrs);
1606 bfd_set_error (bfd_error_system_call);
1607 errno = err;
1608 return NULL;
1610 i_phdrs = (Elf_Internal_Phdr *) &x_phdrs[i_ehdr.e_phnum];
1612 contents_size = 0;
1613 last_phdr = NULL;
1614 loadbase = ehdr_vma;
1615 for (i = 0; i < i_ehdr.e_phnum; ++i)
1617 elf_swap_phdr_in (templ, &x_phdrs[i], &i_phdrs[i]);
1618 /* IA-64 vDSO may have two mappings for one segment, where one mapping
1619 is executable only, and one is read only. We must not use the
1620 executable one. */
1621 if (i_phdrs[i].p_type == PT_LOAD && (i_phdrs[i].p_flags & PF_R))
1623 bfd_vma segment_end;
1624 segment_end = (i_phdrs[i].p_offset + i_phdrs[i].p_filesz
1625 + i_phdrs[i].p_align - 1) & -i_phdrs[i].p_align;
1626 if (segment_end > (bfd_vma) contents_size)
1627 contents_size = segment_end;
1629 if ((i_phdrs[i].p_offset & -i_phdrs[i].p_align) == 0)
1630 loadbase = ehdr_vma - (i_phdrs[i].p_vaddr & -i_phdrs[i].p_align);
1632 last_phdr = &i_phdrs[i];
1635 if (last_phdr == NULL)
1637 /* There were no PT_LOAD segments, so we don't have anything to read. */
1638 free (x_phdrs);
1639 bfd_set_error (bfd_error_wrong_format);
1640 return NULL;
1643 /* Trim the last segment so we don't bother with zeros in the last page
1644 that are off the end of the file. However, if the extra bit in that
1645 page includes the section headers, keep them. */
1646 if ((bfd_vma) contents_size > last_phdr->p_offset + last_phdr->p_filesz
1647 && (bfd_vma) contents_size >= (i_ehdr.e_shoff
1648 + i_ehdr.e_shnum * i_ehdr.e_shentsize))
1650 contents_size = last_phdr->p_offset + last_phdr->p_filesz;
1651 if ((bfd_vma) contents_size < (i_ehdr.e_shoff
1652 + i_ehdr.e_shnum * i_ehdr.e_shentsize))
1653 contents_size = i_ehdr.e_shoff + i_ehdr.e_shnum * i_ehdr.e_shentsize;
1655 else
1656 contents_size = last_phdr->p_offset + last_phdr->p_filesz;
1658 /* Now we know the size of the whole image we want read in. */
1659 contents = bfd_zmalloc (contents_size);
1660 if (contents == NULL)
1662 free (x_phdrs);
1663 bfd_set_error (bfd_error_no_memory);
1664 return NULL;
1667 for (i = 0; i < i_ehdr.e_phnum; ++i)
1668 /* IA-64 vDSO may have two mappings for one segment, where one mapping
1669 is executable only, and one is read only. We must not use the
1670 executable one. */
1671 if (i_phdrs[i].p_type == PT_LOAD && (i_phdrs[i].p_flags & PF_R))
1673 bfd_vma start = i_phdrs[i].p_offset & -i_phdrs[i].p_align;
1674 bfd_vma end = (i_phdrs[i].p_offset + i_phdrs[i].p_filesz
1675 + i_phdrs[i].p_align - 1) & -i_phdrs[i].p_align;
1676 if (end > (bfd_vma) contents_size)
1677 end = contents_size;
1678 err = target_read_memory ((loadbase + i_phdrs[i].p_vaddr)
1679 & -i_phdrs[i].p_align,
1680 contents + start, end - start);
1681 if (err)
1683 free (x_phdrs);
1684 free (contents);
1685 bfd_set_error (bfd_error_system_call);
1686 errno = err;
1687 return NULL;
1690 free (x_phdrs);
1692 /* If the segments visible in memory didn't include the section headers,
1693 then clear them from the file header. */
1694 if ((bfd_vma) contents_size < (i_ehdr.e_shoff
1695 + i_ehdr.e_shnum * i_ehdr.e_shentsize))
1697 memset (&x_ehdr.e_shoff, 0, sizeof x_ehdr.e_shoff);
1698 memset (&x_ehdr.e_shnum, 0, sizeof x_ehdr.e_shnum);
1699 memset (&x_ehdr.e_shstrndx, 0, sizeof x_ehdr.e_shstrndx);
1702 /* This will normally have been in the first PT_LOAD segment. But it
1703 conceivably could be missing, and we might have just changed it. */
1704 memcpy (contents, &x_ehdr, sizeof x_ehdr);
1706 /* Now we have a memory image of the ELF file contents. Make a BFD. */
1707 bim = bfd_malloc (sizeof (struct bfd_in_memory));
1708 if (bim == NULL)
1710 free (contents);
1711 bfd_set_error (bfd_error_no_memory);
1712 return NULL;
1714 nbfd = _bfd_new_bfd ();
1715 if (nbfd == NULL)
1717 free (bim);
1718 free (contents);
1719 bfd_set_error (bfd_error_no_memory);
1720 return NULL;
1722 nbfd->filename = "<in-memory>";
1723 nbfd->xvec = templ->xvec;
1724 bim->size = contents_size;
1725 bim->buffer = contents;
1726 nbfd->iostream = bim;
1727 nbfd->flags = BFD_IN_MEMORY;
1728 nbfd->direction = read_direction;
1729 nbfd->mtime = time (NULL);
1730 nbfd->mtime_set = TRUE;
1732 if (loadbasep)
1733 *loadbasep = loadbase;
1734 return nbfd;
1737 #include "elfcore.h"
1739 /* Size-dependent data and functions. */
1740 const struct elf_size_info NAME(_bfd_elf,size_info) = {
1741 sizeof (Elf_External_Ehdr),
1742 sizeof (Elf_External_Phdr),
1743 sizeof (Elf_External_Shdr),
1744 sizeof (Elf_External_Rel),
1745 sizeof (Elf_External_Rela),
1746 sizeof (Elf_External_Sym),
1747 sizeof (Elf_External_Dyn),
1748 sizeof (Elf_External_Note),
1751 ARCH_SIZE, LOG_FILE_ALIGN,
1752 ELFCLASS, EV_CURRENT,
1753 elf_write_out_phdrs,
1754 elf_write_shdrs_and_ehdr,
1755 elf_write_relocs,
1756 elf_swap_symbol_in,
1757 elf_swap_symbol_out,
1758 elf_slurp_reloc_table,
1759 elf_slurp_symbol_table,
1760 elf_swap_dyn_in,
1761 elf_swap_dyn_out,
1762 elf_swap_reloc_in,
1763 elf_swap_reloc_out,
1764 elf_swap_reloca_in,
1765 elf_swap_reloca_out