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1 /* ELF executable support for BFD.
2 Copyright (C) 1991-2021 Free Software Foundation, Inc.
3
4 Written by Fred Fish @ Cygnus Support, from information published
5 in "UNIX System V Release 4, Programmers Guide: ANSI C and
6 Programming Support Tools". Sufficient support for gdb.
7
8 Rewritten by Mark Eichin @ Cygnus Support, from information
9 published in "System V Application Binary Interface", chapters 4
10 and 5, as well as the various "Processor Supplement" documents
11 derived from it. Added support for assembler and other object file
12 utilities. Further work done by Ken Raeburn (Cygnus Support), Michael
13 Meissner (Open Software Foundation), and Peter Hoogenboom (University
14 of Utah) to finish and extend this.
15
16 This file is part of BFD, the Binary File Descriptor library.
17
18 This program is free software; you can redistribute it and/or modify
19 it under the terms of the GNU General Public License as published by
20 the Free Software Foundation; either version 3 of the License, or
21 (at your option) any later version.
22
23 This program is distributed in the hope that it will be useful,
24 but WITHOUT ANY WARRANTY; without even the implied warranty of
25 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
26 GNU General Public License for more details.
27
28 You should have received a copy of the GNU General Public License
29 along with this program; if not, write to the Free Software
30 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
31 MA 02110-1301, USA. */
32
33
34 /* Problems and other issues to resolve.
35
36 (1) BFD expects there to be some fixed number of "sections" in
37 the object file. I.E. there is a "section_count" variable in the
38 bfd structure which contains the number of sections. However, ELF
39 supports multiple "views" of a file. In particular, with current
40 implementations, executable files typically have two tables, a
41 program header table and a section header table, both of which
42 partition the executable.
43
44 In ELF-speak, the "linking view" of the file uses the section header
45 table to access "sections" within the file, and the "execution view"
46 uses the program header table to access "segments" within the file.
47 "Segments" typically may contain all the data from one or more
48 "sections".
49
50 Note that the section header table is optional in ELF executables,
51 but it is this information that is most useful to gdb. If the
52 section header table is missing, then gdb should probably try
53 to make do with the program header table. (FIXME)
54
55 (2) The code in this file is compiled twice, once in 32-bit mode and
56 once in 64-bit mode. More of it should be made size-independent
57 and moved into elf.c.
58
59 (3) ELF section symbols are handled rather sloppily now. This should
60 be cleaned up, and ELF section symbols reconciled with BFD section
61 symbols.
62
63 (4) We need a published spec for 64-bit ELF. We've got some stuff here
64 that we're using for SPARC V9 64-bit chips, but don't assume that
65 it's cast in stone.
66 */
67
68 #include "sysdep.h"
69 #include "bfd.h"
70 #include "libiberty.h"
71 #include "bfdlink.h"
72 #include "libbfd.h"
73 #include "elf-bfd.h"
74 #include "libiberty.h"
75
76 /* Renaming structures, typedefs, macros and functions to be size-specific. */
77 #define Elf_External_Ehdr NAME(Elf,External_Ehdr)
78 #define Elf_External_Sym NAME(Elf,External_Sym)
79 #define Elf_External_Shdr NAME(Elf,External_Shdr)
80 #define Elf_External_Phdr NAME(Elf,External_Phdr)
81 #define Elf_External_Rel NAME(Elf,External_Rel)
82 #define Elf_External_Rela NAME(Elf,External_Rela)
83 #define Elf_External_Dyn NAME(Elf,External_Dyn)
84
85 #define elf_core_file_failing_command NAME(bfd_elf,core_file_failing_command)
86 #define elf_core_file_failing_signal NAME(bfd_elf,core_file_failing_signal)
87 #define elf_core_file_matches_executable_p \
88 NAME(bfd_elf,core_file_matches_executable_p)
89 #define elf_core_file_pid NAME(bfd_elf,core_file_pid)
90 #define elf_object_p NAME(bfd_elf,object_p)
91 #define elf_core_file_p NAME(bfd_elf,core_file_p)
92 #define elf_get_symtab_upper_bound NAME(bfd_elf,get_symtab_upper_bound)
93 #define elf_get_dynamic_symtab_upper_bound \
94 NAME(bfd_elf,get_dynamic_symtab_upper_bound)
95 #define elf_swap_reloc_in NAME(bfd_elf,swap_reloc_in)
96 #define elf_swap_reloca_in NAME(bfd_elf,swap_reloca_in)
97 #define elf_swap_reloc_out NAME(bfd_elf,swap_reloc_out)
98 #define elf_swap_reloca_out NAME(bfd_elf,swap_reloca_out)
99 #define elf_swap_symbol_in NAME(bfd_elf,swap_symbol_in)
100 #define elf_swap_symbol_out NAME(bfd_elf,swap_symbol_out)
101 #define elf_swap_phdr_in NAME(bfd_elf,swap_phdr_in)
102 #define elf_swap_phdr_out NAME(bfd_elf,swap_phdr_out)
103 #define elf_swap_dyn_in NAME(bfd_elf,swap_dyn_in)
104 #define elf_swap_dyn_out NAME(bfd_elf,swap_dyn_out)
105 #define elf_get_reloc_upper_bound NAME(bfd_elf,get_reloc_upper_bound)
106 #define elf_canonicalize_reloc NAME(bfd_elf,canonicalize_reloc)
107 #define elf_slurp_symbol_table NAME(bfd_elf,slurp_symbol_table)
108 #define elf_canonicalize_symtab NAME(bfd_elf,canonicalize_symtab)
109 #define elf_canonicalize_dynamic_symtab \
110 NAME(bfd_elf,canonicalize_dynamic_symtab)
111 #define elf_get_synthetic_symtab \
112 NAME(bfd_elf,get_synthetic_symtab)
113 #define elf_make_empty_symbol NAME(bfd_elf,make_empty_symbol)
114 #define elf_get_symbol_info NAME(bfd_elf,get_symbol_info)
115 #define elf_get_lineno NAME(bfd_elf,get_lineno)
116 #define elf_set_arch_mach NAME(bfd_elf,set_arch_mach)
117 #define elf_find_nearest_line NAME(bfd_elf,find_nearest_line)
118 #define elf_sizeof_headers NAME(bfd_elf,sizeof_headers)
119 #define elf_set_section_contents NAME(bfd_elf,set_section_contents)
120 #define elf_no_info_to_howto NAME(bfd_elf,no_info_to_howto)
121 #define elf_no_info_to_howto_rel NAME(bfd_elf,no_info_to_howto_rel)
122 #define elf_find_section NAME(bfd_elf,find_section)
123 #define elf_write_shdrs_and_ehdr NAME(bfd_elf,write_shdrs_and_ehdr)
124 #define elf_write_out_phdrs NAME(bfd_elf,write_out_phdrs)
125 #define elf_checksum_contents NAME(bfd_elf,checksum_contents)
126 #define elf_write_relocs NAME(bfd_elf,write_relocs)
127 #define elf_slurp_reloc_table NAME(bfd_elf,slurp_reloc_table)
128
129 #if ARCH_SIZE == 64
130 #define ELF_R_INFO(X,Y) ELF64_R_INFO(X,Y)
131 #define ELF_R_SYM(X) ELF64_R_SYM(X)
132 #define ELF_R_TYPE(X) ELF64_R_TYPE(X)
133 #define ELFCLASS ELFCLASS64
134 #define FILE_ALIGN 8
135 #define LOG_FILE_ALIGN 3
136 #endif
137 #if ARCH_SIZE == 32
138 #define ELF_R_INFO(X,Y) ELF32_R_INFO(X,Y)
139 #define ELF_R_SYM(X) ELF32_R_SYM(X)
140 #define ELF_R_TYPE(X) ELF32_R_TYPE(X)
141 #define ELFCLASS ELFCLASS32
142 #define FILE_ALIGN 4
143 #define LOG_FILE_ALIGN 2
144 #endif
145
146 #if DEBUG & 2
147 static void elf_debug_section (int, Elf_Internal_Shdr *);
148 #endif
149 #if DEBUG & 1
150 static void elf_debug_file (Elf_Internal_Ehdr *);
151 #endif
152 \f
153 /* Structure swapping routines */
154
155 /* Should perhaps use put_offset, put_word, etc. For now, the two versions
156 can be handled by explicitly specifying 32 bits or "the long type". */
157 #if ARCH_SIZE == 64
158 #define H_PUT_WORD H_PUT_64
159 #define H_PUT_SIGNED_WORD H_PUT_S64
160 #define H_GET_WORD H_GET_64
161 #define H_GET_SIGNED_WORD H_GET_S64
162 #endif
163 #if ARCH_SIZE == 32
164 #define H_PUT_WORD H_PUT_32
165 #define H_PUT_SIGNED_WORD H_PUT_S32
166 #define H_GET_WORD H_GET_32
167 #define H_GET_SIGNED_WORD H_GET_S32
168 #endif
169
170 /* Translate an ELF symbol in external format into an ELF symbol in internal
171 format. */
172
173 bfd_boolean
174 elf_swap_symbol_in (bfd *abfd,
175 const void *psrc,
176 const void *pshn,
177 Elf_Internal_Sym *dst)
178 {
179 const Elf_External_Sym *src = (const Elf_External_Sym *) psrc;
180 const Elf_External_Sym_Shndx *shndx = (const Elf_External_Sym_Shndx *) pshn;
181 int signed_vma = get_elf_backend_data (abfd)->sign_extend_vma;
182
183 dst->st_name = H_GET_32 (abfd, src->st_name);
184 if (signed_vma)
185 dst->st_value = H_GET_SIGNED_WORD (abfd, src->st_value);
186 else
187 dst->st_value = H_GET_WORD (abfd, src->st_value);
188 dst->st_size = H_GET_WORD (abfd, src->st_size);
189 dst->st_info = H_GET_8 (abfd, src->st_info);
190 dst->st_other = H_GET_8 (abfd, src->st_other);
191 dst->st_shndx = H_GET_16 (abfd, src->st_shndx);
192 if (dst->st_shndx == (SHN_XINDEX & 0xffff))
193 {
194 if (shndx == NULL)
195 return FALSE;
196 dst->st_shndx = H_GET_32 (abfd, shndx->est_shndx);
197 }
198 else if (dst->st_shndx >= (SHN_LORESERVE & 0xffff))
199 dst->st_shndx += SHN_LORESERVE - (SHN_LORESERVE & 0xffff);
200 dst->st_target_internal = 0;
201 return TRUE;
202 }
203
204 /* Translate an ELF symbol in internal format into an ELF symbol in external
205 format. */
206
207 void
208 elf_swap_symbol_out (bfd *abfd,
209 const Elf_Internal_Sym *src,
210 void *cdst,
211 void *shndx)
212 {
213 unsigned int tmp;
214 Elf_External_Sym *dst = (Elf_External_Sym *) cdst;
215 H_PUT_32 (abfd, src->st_name, dst->st_name);
216 H_PUT_WORD (abfd, src->st_value, dst->st_value);
217 H_PUT_WORD (abfd, src->st_size, dst->st_size);
218 H_PUT_8 (abfd, src->st_info, dst->st_info);
219 H_PUT_8 (abfd, src->st_other, dst->st_other);
220 tmp = src->st_shndx;
221 if (tmp >= (SHN_LORESERVE & 0xffff) && tmp < SHN_LORESERVE)
222 {
223 if (shndx == NULL)
224 abort ();
225 H_PUT_32 (abfd, tmp, shndx);
226 tmp = SHN_XINDEX & 0xffff;
227 }
228 H_PUT_16 (abfd, tmp, dst->st_shndx);
229 }
230
231 /* Translate an ELF file header in external format into an ELF file header in
232 internal format. */
233
234 static void
235 elf_swap_ehdr_in (bfd *abfd,
236 const Elf_External_Ehdr *src,
237 Elf_Internal_Ehdr *dst)
238 {
239 int signed_vma = get_elf_backend_data (abfd)->sign_extend_vma;
240 memcpy (dst->e_ident, src->e_ident, EI_NIDENT);
241 dst->e_type = H_GET_16 (abfd, src->e_type);
242 dst->e_machine = H_GET_16 (abfd, src->e_machine);
243 dst->e_version = H_GET_32 (abfd, src->e_version);
244 if (signed_vma)
245 dst->e_entry = H_GET_SIGNED_WORD (abfd, src->e_entry);
246 else
247 dst->e_entry = H_GET_WORD (abfd, src->e_entry);
248 dst->e_phoff = H_GET_WORD (abfd, src->e_phoff);
249 dst->e_shoff = H_GET_WORD (abfd, src->e_shoff);
250 dst->e_flags = H_GET_32 (abfd, src->e_flags);
251 dst->e_ehsize = H_GET_16 (abfd, src->e_ehsize);
252 dst->e_phentsize = H_GET_16 (abfd, src->e_phentsize);
253 dst->e_phnum = H_GET_16 (abfd, src->e_phnum);
254 dst->e_shentsize = H_GET_16 (abfd, src->e_shentsize);
255 dst->e_shnum = H_GET_16 (abfd, src->e_shnum);
256 dst->e_shstrndx = H_GET_16 (abfd, src->e_shstrndx);
257 }
258
259 /* Translate an ELF file header in internal format into an ELF file header in
260 external format. */
261
262 static void
263 elf_swap_ehdr_out (bfd *abfd,
264 const Elf_Internal_Ehdr *src,
265 Elf_External_Ehdr *dst)
266 {
267 unsigned int tmp;
268 int signed_vma = get_elf_backend_data (abfd)->sign_extend_vma;
269 memcpy (dst->e_ident, src->e_ident, EI_NIDENT);
270 /* note that all elements of dst are *arrays of unsigned char* already... */
271 H_PUT_16 (abfd, src->e_type, dst->e_type);
272 H_PUT_16 (abfd, src->e_machine, dst->e_machine);
273 H_PUT_32 (abfd, src->e_version, dst->e_version);
274 if (signed_vma)
275 H_PUT_SIGNED_WORD (abfd, src->e_entry, dst->e_entry);
276 else
277 H_PUT_WORD (abfd, src->e_entry, dst->e_entry);
278 H_PUT_WORD (abfd, src->e_phoff, dst->e_phoff);
279 H_PUT_WORD (abfd, src->e_shoff, dst->e_shoff);
280 H_PUT_32 (abfd, src->e_flags, dst->e_flags);
281 H_PUT_16 (abfd, src->e_ehsize, dst->e_ehsize);
282 H_PUT_16 (abfd, src->e_phentsize, dst->e_phentsize);
283 tmp = src->e_phnum;
284 if (tmp > PN_XNUM)
285 tmp = PN_XNUM;
286 H_PUT_16 (abfd, tmp, dst->e_phnum);
287 H_PUT_16 (abfd, src->e_shentsize, dst->e_shentsize);
288 tmp = src->e_shnum;
289 if (tmp >= (SHN_LORESERVE & 0xffff))
290 tmp = SHN_UNDEF;
291 H_PUT_16 (abfd, tmp, dst->e_shnum);
292 tmp = src->e_shstrndx;
293 if (tmp >= (SHN_LORESERVE & 0xffff))
294 tmp = SHN_XINDEX & 0xffff;
295 H_PUT_16 (abfd, tmp, dst->e_shstrndx);
296 }
297
298 /* Translate an ELF section header table entry in external format into an
299 ELF section header table entry in internal format. */
300
301 static void
302 elf_swap_shdr_in (bfd *abfd,
303 const Elf_External_Shdr *src,
304 Elf_Internal_Shdr *dst)
305 {
306 int signed_vma = get_elf_backend_data (abfd)->sign_extend_vma;
307
308 dst->sh_name = H_GET_32 (abfd, src->sh_name);
309 dst->sh_type = H_GET_32 (abfd, src->sh_type);
310 dst->sh_flags = H_GET_WORD (abfd, src->sh_flags);
311 if (signed_vma)
312 dst->sh_addr = H_GET_SIGNED_WORD (abfd, src->sh_addr);
313 else
314 dst->sh_addr = H_GET_WORD (abfd, src->sh_addr);
315 dst->sh_offset = H_GET_WORD (abfd, src->sh_offset);
316 dst->sh_size = H_GET_WORD (abfd, src->sh_size);
317 /* PR 23657. Check for invalid section size, in sections with contents.
318 Note - we do not set an error value here because the contents
319 of this particular section might not be needed by the consumer. */
320 if (dst->sh_type != SHT_NOBITS)
321 {
322 ufile_ptr filesize = bfd_get_file_size (abfd);
323
324 if (filesize != 0
325 && ((ufile_ptr) dst->sh_offset > filesize
326 || dst->sh_size > filesize - dst->sh_offset))
327 {
328 abfd->read_only = 1;
329 _bfd_error_handler (_("warning: %pB has a section "
330 "extending past end of file"), abfd);
331 }
332 }
333 dst->sh_link = H_GET_32 (abfd, src->sh_link);
334 dst->sh_info = H_GET_32 (abfd, src->sh_info);
335 dst->sh_addralign = H_GET_WORD (abfd, src->sh_addralign);
336 dst->sh_entsize = H_GET_WORD (abfd, src->sh_entsize);
337 dst->bfd_section = NULL;
338 dst->contents = NULL;
339 }
340
341 /* Translate an ELF section header table entry in internal format into an
342 ELF section header table entry in external format. */
343
344 static void
345 elf_swap_shdr_out (bfd *abfd,
346 const Elf_Internal_Shdr *src,
347 Elf_External_Shdr *dst)
348 {
349 /* note that all elements of dst are *arrays of unsigned char* already... */
350 H_PUT_32 (abfd, src->sh_name, dst->sh_name);
351 H_PUT_32 (abfd, src->sh_type, dst->sh_type);
352 H_PUT_WORD (abfd, src->sh_flags, dst->sh_flags);
353 H_PUT_WORD (abfd, src->sh_addr, dst->sh_addr);
354 H_PUT_WORD (abfd, src->sh_offset, dst->sh_offset);
355 H_PUT_WORD (abfd, src->sh_size, dst->sh_size);
356 H_PUT_32 (abfd, src->sh_link, dst->sh_link);
357 H_PUT_32 (abfd, src->sh_info, dst->sh_info);
358 H_PUT_WORD (abfd, src->sh_addralign, dst->sh_addralign);
359 H_PUT_WORD (abfd, src->sh_entsize, dst->sh_entsize);
360 }
361
362 /* Translate an ELF program header table entry in external format into an
363 ELF program header table entry in internal format. */
364
365 void
366 elf_swap_phdr_in (bfd *abfd,
367 const Elf_External_Phdr *src,
368 Elf_Internal_Phdr *dst)
369 {
370 int signed_vma = get_elf_backend_data (abfd)->sign_extend_vma;
371
372 dst->p_type = H_GET_32 (abfd, src->p_type);
373 dst->p_flags = H_GET_32 (abfd, src->p_flags);
374 dst->p_offset = H_GET_WORD (abfd, src->p_offset);
375 if (signed_vma)
376 {
377 dst->p_vaddr = H_GET_SIGNED_WORD (abfd, src->p_vaddr);
378 dst->p_paddr = H_GET_SIGNED_WORD (abfd, src->p_paddr);
379 }
380 else
381 {
382 dst->p_vaddr = H_GET_WORD (abfd, src->p_vaddr);
383 dst->p_paddr = H_GET_WORD (abfd, src->p_paddr);
384 }
385 dst->p_filesz = H_GET_WORD (abfd, src->p_filesz);
386 dst->p_memsz = H_GET_WORD (abfd, src->p_memsz);
387 dst->p_align = H_GET_WORD (abfd, src->p_align);
388 }
389
390 void
391 elf_swap_phdr_out (bfd *abfd,
392 const Elf_Internal_Phdr *src,
393 Elf_External_Phdr *dst)
394 {
395 const struct elf_backend_data *bed;
396 bfd_vma p_paddr;
397
398 bed = get_elf_backend_data (abfd);
399 p_paddr = bed->want_p_paddr_set_to_zero ? 0 : src->p_paddr;
400
401 /* note that all elements of dst are *arrays of unsigned char* already... */
402 H_PUT_32 (abfd, src->p_type, dst->p_type);
403 H_PUT_WORD (abfd, src->p_offset, dst->p_offset);
404 H_PUT_WORD (abfd, src->p_vaddr, dst->p_vaddr);
405 H_PUT_WORD (abfd, p_paddr, dst->p_paddr);
406 H_PUT_WORD (abfd, src->p_filesz, dst->p_filesz);
407 H_PUT_WORD (abfd, src->p_memsz, dst->p_memsz);
408 H_PUT_32 (abfd, src->p_flags, dst->p_flags);
409 H_PUT_WORD (abfd, src->p_align, dst->p_align);
410 }
411
412 /* Translate an ELF reloc from external format to internal format. */
413 void
414 elf_swap_reloc_in (bfd *abfd,
415 const bfd_byte *s,
416 Elf_Internal_Rela *dst)
417 {
418 const Elf_External_Rel *src = (const Elf_External_Rel *) s;
419 dst->r_offset = H_GET_WORD (abfd, src->r_offset);
420 dst->r_info = H_GET_WORD (abfd, src->r_info);
421 dst->r_addend = 0;
422 }
423
424 void
425 elf_swap_reloca_in (bfd *abfd,
426 const bfd_byte *s,
427 Elf_Internal_Rela *dst)
428 {
429 const Elf_External_Rela *src = (const Elf_External_Rela *) s;
430 dst->r_offset = H_GET_WORD (abfd, src->r_offset);
431 dst->r_info = H_GET_WORD (abfd, src->r_info);
432 dst->r_addend = H_GET_SIGNED_WORD (abfd, src->r_addend);
433 }
434
435 /* Translate an ELF reloc from internal format to external format. */
436 void
437 elf_swap_reloc_out (bfd *abfd,
438 const Elf_Internal_Rela *src,
439 bfd_byte *d)
440 {
441 Elf_External_Rel *dst = (Elf_External_Rel *) d;
442 H_PUT_WORD (abfd, src->r_offset, dst->r_offset);
443 H_PUT_WORD (abfd, src->r_info, dst->r_info);
444 }
445
446 void
447 elf_swap_reloca_out (bfd *abfd,
448 const Elf_Internal_Rela *src,
449 bfd_byte *d)
450 {
451 Elf_External_Rela *dst = (Elf_External_Rela *) d;
452 H_PUT_WORD (abfd, src->r_offset, dst->r_offset);
453 H_PUT_WORD (abfd, src->r_info, dst->r_info);
454 H_PUT_SIGNED_WORD (abfd, src->r_addend, dst->r_addend);
455 }
456
457 void
458 elf_swap_dyn_in (bfd *abfd,
459 const void *p,
460 Elf_Internal_Dyn *dst)
461 {
462 const Elf_External_Dyn *src = (const Elf_External_Dyn *) p;
463
464 dst->d_tag = H_GET_WORD (abfd, src->d_tag);
465 dst->d_un.d_val = H_GET_WORD (abfd, src->d_un.d_val);
466 }
467
468 void
469 elf_swap_dyn_out (bfd *abfd,
470 const Elf_Internal_Dyn *src,
471 void *p)
472 {
473 Elf_External_Dyn *dst = (Elf_External_Dyn *) p;
474
475 H_PUT_WORD (abfd, src->d_tag, dst->d_tag);
476 H_PUT_WORD (abfd, src->d_un.d_val, dst->d_un.d_val);
477 }
478 \f
479 /* ELF .o/exec file reading */
480
481 /* Begin processing a given object.
482
483 First we validate the file by reading in the ELF header and checking
484 the magic number. */
485
486 static inline bfd_boolean
487 elf_file_p (Elf_External_Ehdr *x_ehdrp)
488 {
489 return ((x_ehdrp->e_ident[EI_MAG0] == ELFMAG0)
490 && (x_ehdrp->e_ident[EI_MAG1] == ELFMAG1)
491 && (x_ehdrp->e_ident[EI_MAG2] == ELFMAG2)
492 && (x_ehdrp->e_ident[EI_MAG3] == ELFMAG3));
493 }
494
495 /* Check to see if the file associated with ABFD matches the target vector
496 that ABFD points to.
497
498 Note that we may be called several times with the same ABFD, but different
499 target vectors, most of which will not match. We have to avoid leaving
500 any side effects in ABFD, or any data it points to (like tdata), if the
501 file does not match the target vector. */
502
503 bfd_cleanup
504 elf_object_p (bfd *abfd)
505 {
506 Elf_External_Ehdr x_ehdr; /* Elf file header, external form */
507 Elf_Internal_Ehdr *i_ehdrp; /* Elf file header, internal form */
508 Elf_External_Shdr x_shdr; /* Section header table entry, external form */
509 Elf_Internal_Shdr i_shdr;
510 Elf_Internal_Shdr *i_shdrp; /* Section header table, internal form */
511 unsigned int shindex;
512 const struct elf_backend_data *ebd;
513 asection *s;
514 const bfd_target *target;
515
516 /* Read in the ELF header in external format. */
517
518 if (bfd_bread (&x_ehdr, sizeof (x_ehdr), abfd) != sizeof (x_ehdr))
519 {
520 if (bfd_get_error () != bfd_error_system_call)
521 goto got_wrong_format_error;
522 else
523 goto got_no_match;
524 }
525
526 /* Now check to see if we have a valid ELF file, and one that BFD can
527 make use of. The magic number must match, the address size ('class')
528 and byte-swapping must match our XVEC entry, and it must have a
529 section header table (FIXME: See comments re sections at top of this
530 file). */
531
532 if (! elf_file_p (&x_ehdr)
533 || x_ehdr.e_ident[EI_VERSION] != EV_CURRENT
534 || x_ehdr.e_ident[EI_CLASS] != ELFCLASS)
535 goto got_wrong_format_error;
536
537 /* Check that file's byte order matches xvec's */
538 switch (x_ehdr.e_ident[EI_DATA])
539 {
540 case ELFDATA2MSB: /* Big-endian */
541 if (! bfd_header_big_endian (abfd))
542 goto got_wrong_format_error;
543 break;
544 case ELFDATA2LSB: /* Little-endian */
545 if (! bfd_header_little_endian (abfd))
546 goto got_wrong_format_error;
547 break;
548 case ELFDATANONE: /* No data encoding specified */
549 default: /* Unknown data encoding specified */
550 goto got_wrong_format_error;
551 }
552
553 target = abfd->xvec;
554
555 /* Allocate an instance of the elf_obj_tdata structure and hook it up to
556 the tdata pointer in the bfd. */
557
558 if (! (*target->_bfd_set_format[bfd_object]) (abfd))
559 goto got_no_match;
560
561 /* Now that we know the byte order, swap in the rest of the header */
562 i_ehdrp = elf_elfheader (abfd);
563 elf_swap_ehdr_in (abfd, &x_ehdr, i_ehdrp);
564 #if DEBUG & 1
565 elf_debug_file (i_ehdrp);
566 #endif
567
568 /* Reject ET_CORE (header indicates core file, not object file) */
569 if (i_ehdrp->e_type == ET_CORE)
570 goto got_wrong_format_error;
571
572 /* If this is a relocatable file and there is no section header
573 table, then we're hosed. */
574 if (i_ehdrp->e_shoff < sizeof (x_ehdr) && i_ehdrp->e_type == ET_REL)
575 goto got_wrong_format_error;
576
577 /* As a simple sanity check, verify that what BFD thinks is the
578 size of each section header table entry actually matches the size
579 recorded in the file, but only if there are any sections. */
580 if (i_ehdrp->e_shentsize != sizeof (x_shdr) && i_ehdrp->e_shnum != 0)
581 goto got_wrong_format_error;
582
583 /* Further sanity check. */
584 if (i_ehdrp->e_shoff < sizeof (x_ehdr) && i_ehdrp->e_shnum != 0)
585 goto got_wrong_format_error;
586
587 ebd = get_elf_backend_data (abfd);
588 if (ebd->s->arch_size != ARCH_SIZE)
589 goto got_wrong_format_error;
590
591 /* Check that the ELF e_machine field matches what this particular
592 BFD format expects. */
593 if (ebd->elf_machine_code != i_ehdrp->e_machine
594 && (ebd->elf_machine_alt1 == 0
595 || i_ehdrp->e_machine != ebd->elf_machine_alt1)
596 && (ebd->elf_machine_alt2 == 0
597 || i_ehdrp->e_machine != ebd->elf_machine_alt2)
598 && ebd->elf_machine_code != EM_NONE)
599 goto got_wrong_format_error;
600
601 if (i_ehdrp->e_type == ET_EXEC)
602 abfd->flags |= EXEC_P;
603 else if (i_ehdrp->e_type == ET_DYN)
604 abfd->flags |= DYNAMIC;
605
606 if (i_ehdrp->e_phnum > 0)
607 abfd->flags |= D_PAGED;
608
609 if (! bfd_default_set_arch_mach (abfd, ebd->arch, 0))
610 {
611 /* It's OK if this fails for the generic target. */
612 if (ebd->elf_machine_code != EM_NONE)
613 goto got_no_match;
614 }
615
616 if (ebd->elf_machine_code != EM_NONE
617 && i_ehdrp->e_ident[EI_OSABI] != ebd->elf_osabi
618 && ebd->elf_osabi != ELFOSABI_NONE)
619 goto got_wrong_format_error;
620
621 if (i_ehdrp->e_shoff >= sizeof (x_ehdr))
622 {
623 file_ptr where = (file_ptr) i_ehdrp->e_shoff;
624
625 /* Seek to the section header table in the file. */
626 if (bfd_seek (abfd, where, SEEK_SET) != 0)
627 goto got_no_match;
628
629 /* Read the first section header at index 0, and convert to internal
630 form. */
631 if (bfd_bread (&x_shdr, sizeof x_shdr, abfd) != sizeof (x_shdr))
632 goto got_no_match;
633 elf_swap_shdr_in (abfd, &x_shdr, &i_shdr);
634
635 /* If the section count is zero, the actual count is in the first
636 section header. */
637 if (i_ehdrp->e_shnum == SHN_UNDEF)
638 {
639 i_ehdrp->e_shnum = i_shdr.sh_size;
640 if (i_ehdrp->e_shnum >= SHN_LORESERVE
641 || i_ehdrp->e_shnum != i_shdr.sh_size
642 || i_ehdrp->e_shnum == 0)
643 goto got_wrong_format_error;
644 }
645
646 /* And similarly for the string table index. */
647 if (i_ehdrp->e_shstrndx == (SHN_XINDEX & 0xffff))
648 {
649 i_ehdrp->e_shstrndx = i_shdr.sh_link;
650 if (i_ehdrp->e_shstrndx != i_shdr.sh_link)
651 goto got_wrong_format_error;
652 }
653
654 /* And program headers. */
655 if (i_ehdrp->e_phnum == PN_XNUM && i_shdr.sh_info != 0)
656 {
657 i_ehdrp->e_phnum = i_shdr.sh_info;
658 if (i_ehdrp->e_phnum != i_shdr.sh_info)
659 goto got_wrong_format_error;
660 }
661
662 /* Sanity check that we can read all of the section headers.
663 It ought to be good enough to just read the last one. */
664 if (i_ehdrp->e_shnum != 1)
665 {
666 /* Check that we don't have a totally silly number of sections. */
667 if (i_ehdrp->e_shnum > (unsigned int) -1 / sizeof (x_shdr)
668 || i_ehdrp->e_shnum > (unsigned int) -1 / sizeof (i_shdr))
669 goto got_wrong_format_error;
670
671 where += (i_ehdrp->e_shnum - 1) * sizeof (x_shdr);
672 if ((bfd_size_type) where <= i_ehdrp->e_shoff)
673 goto got_wrong_format_error;
674
675 if (bfd_seek (abfd, where, SEEK_SET) != 0)
676 goto got_no_match;
677 if (bfd_bread (&x_shdr, sizeof x_shdr, abfd) != sizeof (x_shdr))
678 goto got_no_match;
679
680 /* Back to where we were. */
681 where = i_ehdrp->e_shoff + sizeof (x_shdr);
682 if (bfd_seek (abfd, where, SEEK_SET) != 0)
683 goto got_no_match;
684 }
685 }
686
687 /* Allocate space for a copy of the section header table in
688 internal form. */
689 if (i_ehdrp->e_shnum != 0)
690 {
691 Elf_Internal_Shdr *shdrp;
692 unsigned int num_sec;
693 size_t amt;
694
695 if (_bfd_mul_overflow (i_ehdrp->e_shnum, sizeof (*i_shdrp), &amt))
696 goto got_wrong_format_error;
697 i_shdrp = (Elf_Internal_Shdr *) bfd_alloc (abfd, amt);
698 if (!i_shdrp)
699 goto got_no_match;
700 num_sec = i_ehdrp->e_shnum;
701 elf_numsections (abfd) = num_sec;
702 if (_bfd_mul_overflow (num_sec, sizeof (i_shdrp), &amt))
703 goto got_wrong_format_error;
704 elf_elfsections (abfd) = (Elf_Internal_Shdr **) bfd_alloc (abfd, amt);
705 if (!elf_elfsections (abfd))
706 goto got_no_match;
707 elf_tdata (abfd)->being_created = bfd_zalloc (abfd, num_sec);
708 if (!elf_tdata (abfd)->being_created)
709 goto got_no_match;
710
711 memcpy (i_shdrp, &i_shdr, sizeof (*i_shdrp));
712 for (shdrp = i_shdrp, shindex = 0; shindex < num_sec; shindex++)
713 elf_elfsections (abfd)[shindex] = shdrp++;
714
715 /* Read in the rest of the section header table and convert it
716 to internal form. */
717 for (shindex = 1; shindex < i_ehdrp->e_shnum; shindex++)
718 {
719 if (bfd_bread (&x_shdr, sizeof x_shdr, abfd) != sizeof (x_shdr))
720 goto got_no_match;
721 elf_swap_shdr_in (abfd, &x_shdr, i_shdrp + shindex);
722
723 /* Sanity check sh_link and sh_info. */
724 if (i_shdrp[shindex].sh_link >= num_sec)
725 {
726 /* PR 10478: Accept Solaris binaries with a sh_link
727 field set to SHN_BEFORE or SHN_AFTER. */
728 switch (ebd->elf_machine_code)
729 {
730 case EM_386:
731 case EM_IAMCU:
732 case EM_X86_64:
733 case EM_OLD_SPARCV9:
734 case EM_SPARC32PLUS:
735 case EM_SPARCV9:
736 case EM_SPARC:
737 if (i_shdrp[shindex].sh_link == (SHN_LORESERVE & 0xffff) /* SHN_BEFORE */
738 || i_shdrp[shindex].sh_link == ((SHN_LORESERVE + 1) & 0xffff) /* SHN_AFTER */)
739 break;
740 /* Otherwise fall through. */
741 default:
742 goto got_wrong_format_error;
743 }
744 }
745
746 if (((i_shdrp[shindex].sh_flags & SHF_INFO_LINK)
747 || i_shdrp[shindex].sh_type == SHT_RELA
748 || i_shdrp[shindex].sh_type == SHT_REL)
749 && i_shdrp[shindex].sh_info >= num_sec)
750 goto got_wrong_format_error;
751
752 /* If the section is loaded, but not page aligned, clear
753 D_PAGED. */
754 if (i_shdrp[shindex].sh_size != 0
755 && (i_shdrp[shindex].sh_flags & SHF_ALLOC) != 0
756 && i_shdrp[shindex].sh_type != SHT_NOBITS
757 && (((i_shdrp[shindex].sh_addr - i_shdrp[shindex].sh_offset)
758 % ebd->minpagesize)
759 != 0))
760 abfd->flags &= ~D_PAGED;
761 }
762
763 if (i_ehdrp->e_shstrndx >= elf_numsections (abfd)
764 || i_shdrp[i_ehdrp->e_shstrndx].sh_type != SHT_STRTAB)
765 {
766 /* PR 2257:
767 We used to just goto got_wrong_format_error here
768 but there are binaries in existance for which this test
769 will prevent the binutils from working with them at all.
770 So we are kind, and reset the string index value to 0
771 so that at least some processing can be done. */
772 i_ehdrp->e_shstrndx = SHN_UNDEF;
773 abfd->read_only = 1;
774 _bfd_error_handler
775 (_("warning: %pB has a corrupt string table index - ignoring"),
776 abfd);
777 }
778 }
779 else if (i_ehdrp->e_shstrndx != SHN_UNDEF)
780 goto got_wrong_format_error;
781
782 /* Read in the program headers. */
783 if (i_ehdrp->e_phnum == 0)
784 elf_tdata (abfd)->phdr = NULL;
785 else
786 {
787 Elf_Internal_Phdr *i_phdr;
788 unsigned int i;
789 ufile_ptr filesize;
790 size_t amt;
791
792 /* Check for a corrupt input file with an impossibly large number
793 of program headers. */
794 filesize = bfd_get_file_size (abfd);
795 if (filesize != 0
796 && i_ehdrp->e_phnum > filesize / sizeof (Elf_External_Phdr))
797 goto got_wrong_format_error;
798 if (_bfd_mul_overflow (i_ehdrp->e_phnum, sizeof (*i_phdr), &amt))
799 goto got_wrong_format_error;
800 elf_tdata (abfd)->phdr
801 = (Elf_Internal_Phdr *) bfd_alloc (abfd, amt);
802 if (elf_tdata (abfd)->phdr == NULL)
803 goto got_no_match;
804 if (bfd_seek (abfd, (file_ptr) i_ehdrp->e_phoff, SEEK_SET) != 0)
805 goto got_no_match;
806 i_phdr = elf_tdata (abfd)->phdr;
807 for (i = 0; i < i_ehdrp->e_phnum; i++, i_phdr++)
808 {
809 Elf_External_Phdr x_phdr;
810
811 if (bfd_bread (&x_phdr, sizeof x_phdr, abfd) != sizeof x_phdr)
812 goto got_no_match;
813 elf_swap_phdr_in (abfd, &x_phdr, i_phdr);
814 /* Too much code in BFD relies on alignment being a power of
815 two, as required by the ELF spec. */
816 if (i_phdr->p_align != (i_phdr->p_align & -i_phdr->p_align))
817 {
818 abfd->read_only = 1;
819 _bfd_error_handler (_("warning: %pB has a program header "
820 "with invalid alignment"), abfd);
821 }
822 }
823 }
824
825 if (i_ehdrp->e_shstrndx != 0 && i_ehdrp->e_shoff >= sizeof (x_ehdr))
826 {
827 unsigned int num_sec;
828
829 /* Once all of the section headers have been read and converted, we
830 can start processing them. Note that the first section header is
831 a dummy placeholder entry, so we ignore it. */
832 num_sec = elf_numsections (abfd);
833 for (shindex = 1; shindex < num_sec; shindex++)
834 if (!bfd_section_from_shdr (abfd, shindex))
835 goto got_no_match;
836
837 /* Set up ELF sections for SHF_GROUP and SHF_LINK_ORDER. */
838 if (! _bfd_elf_setup_sections (abfd))
839 goto got_wrong_format_error;
840 }
841
842 /* Let the backend double check the format and override global
843 information. */
844 if (ebd->elf_backend_object_p)
845 {
846 if (! (*ebd->elf_backend_object_p) (abfd))
847 goto got_wrong_format_error;
848 }
849
850 /* Remember the entry point specified in the ELF file header. */
851 bfd_set_start_address (abfd, i_ehdrp->e_entry);
852
853 /* If we have created any reloc sections that are associated with
854 debugging sections, mark the reloc sections as debugging as well. */
855 for (s = abfd->sections; s != NULL; s = s->next)
856 {
857 if ((elf_section_data (s)->this_hdr.sh_type == SHT_REL
858 || elf_section_data (s)->this_hdr.sh_type == SHT_RELA)
859 && elf_section_data (s)->this_hdr.sh_info > 0)
860 {
861 unsigned long targ_index;
862 asection *targ_sec;
863
864 targ_index = elf_section_data (s)->this_hdr.sh_info;
865 targ_sec = bfd_section_from_elf_index (abfd, targ_index);
866 if (targ_sec != NULL
867 && (targ_sec->flags & SEC_DEBUGGING) != 0)
868 s->flags |= SEC_DEBUGGING;
869 }
870 }
871 return _bfd_no_cleanup;
872
873 got_wrong_format_error:
874 bfd_set_error (bfd_error_wrong_format);
875
876 got_no_match:
877 return NULL;
878 }
879 \f
880 /* ELF .o/exec file writing */
881
882 /* Write out the relocs. */
883
884 void
885 elf_write_relocs (bfd *abfd, asection *sec, void *data)
886 {
887 const struct elf_backend_data * const bed = get_elf_backend_data (abfd);
888 bfd_boolean *failedp = (bfd_boolean *) data;
889 Elf_Internal_Shdr *rela_hdr;
890 bfd_vma addr_offset;
891 void (*swap_out) (bfd *, const Elf_Internal_Rela *, bfd_byte *);
892 size_t extsize;
893 bfd_byte *dst_rela;
894 unsigned int idx;
895 asymbol *last_sym;
896 int last_sym_idx;
897 size_t amt;
898
899 /* If we have already failed, don't do anything. */
900 if (*failedp)
901 return;
902
903 if ((sec->flags & SEC_RELOC) == 0)
904 return;
905
906 /* The linker backend writes the relocs out itself, and sets the
907 reloc_count field to zero to inhibit writing them here. Also,
908 sometimes the SEC_RELOC flag gets set even when there aren't any
909 relocs. */
910 if (sec->reloc_count == 0)
911 return;
912
913 /* If we have opened an existing file for update, reloc_count may be
914 set even though we are not linking. In that case we have nothing
915 to do. */
916 if (sec->orelocation == NULL)
917 return;
918
919 rela_hdr = elf_section_data (sec)->rela.hdr;
920 if (rela_hdr == NULL)
921 rela_hdr = elf_section_data (sec)->rel.hdr;
922
923 rela_hdr->sh_size = rela_hdr->sh_entsize * sec->reloc_count;
924 if (_bfd_mul_overflow (sec->reloc_count, rela_hdr->sh_entsize, &amt)
925 || (rela_hdr->contents = bfd_alloc (abfd, amt)) == NULL)
926 {
927 bfd_set_error (bfd_error_no_memory);
928 *failedp = TRUE;
929 return;
930 }
931
932 /* Figure out whether the relocations are RELA or REL relocations. */
933 if (rela_hdr->sh_type == SHT_RELA)
934 {
935 swap_out = elf_swap_reloca_out;
936 extsize = sizeof (Elf_External_Rela);
937 }
938 else if (rela_hdr->sh_type == SHT_REL)
939 {
940 swap_out = elf_swap_reloc_out;
941 extsize = sizeof (Elf_External_Rel);
942 }
943 else
944 /* Every relocation section should be either an SHT_RELA or an
945 SHT_REL section. */
946 abort ();
947
948 /* The address of an ELF reloc is section relative for an object
949 file, and absolute for an executable file or shared library.
950 The address of a BFD reloc is always section relative. */
951 addr_offset = 0;
952 if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
953 addr_offset = sec->vma;
954
955 /* orelocation has the data, reloc_count has the count... */
956 last_sym = 0;
957 last_sym_idx = 0;
958 dst_rela = rela_hdr->contents;
959
960 for (idx = 0; idx < sec->reloc_count; idx++, dst_rela += extsize)
961 {
962 Elf_Internal_Rela src_rela;
963 arelent *ptr;
964 asymbol *sym;
965 int n;
966
967 ptr = sec->orelocation[idx];
968 sym = *ptr->sym_ptr_ptr;
969 if (sym == last_sym)
970 n = last_sym_idx;
971 else if (bfd_is_abs_section (sym->section) && sym->value == 0)
972 n = STN_UNDEF;
973 else
974 {
975 last_sym = sym;
976 n = _bfd_elf_symbol_from_bfd_symbol (abfd, &sym);
977 if (n < 0)
978 {
979 *failedp = TRUE;
980 return;
981 }
982 last_sym_idx = n;
983 }
984
985 if ((*ptr->sym_ptr_ptr)->the_bfd != NULL
986 && (*ptr->sym_ptr_ptr)->the_bfd->xvec != abfd->xvec
987 && ! _bfd_elf_validate_reloc (abfd, ptr))
988 {
989 *failedp = TRUE;
990 return;
991 }
992
993 if (ptr->howto == NULL)
994 {
995 *failedp = TRUE;
996 return;
997 }
998
999 src_rela.r_offset = ptr->address + addr_offset;
1000 src_rela.r_info = ELF_R_INFO (n, ptr->howto->type);
1001 src_rela.r_addend = ptr->addend;
1002 (*swap_out) (abfd, &src_rela, dst_rela);
1003 }
1004
1005 if (elf_section_data (sec)->has_secondary_relocs
1006 && !bed->write_secondary_relocs (abfd, sec))
1007 {
1008 *failedp = TRUE;
1009 return;
1010 }
1011 }
1012
1013 /* Write out the program headers. */
1014
1015 int
1016 elf_write_out_phdrs (bfd *abfd,
1017 const Elf_Internal_Phdr *phdr,
1018 unsigned int count)
1019 {
1020 while (count--)
1021 {
1022 Elf_External_Phdr extphdr;
1023
1024 elf_swap_phdr_out (abfd, phdr, &extphdr);
1025 if (bfd_bwrite (&extphdr, sizeof (Elf_External_Phdr), abfd)
1026 != sizeof (Elf_External_Phdr))
1027 return -1;
1028 phdr++;
1029 }
1030 return 0;
1031 }
1032
1033 /* Write out the section headers and the ELF file header. */
1034
1035 bfd_boolean
1036 elf_write_shdrs_and_ehdr (bfd *abfd)
1037 {
1038 Elf_External_Ehdr x_ehdr; /* Elf file header, external form */
1039 Elf_Internal_Ehdr *i_ehdrp; /* Elf file header, internal form */
1040 Elf_External_Shdr *x_shdrp; /* Section header table, external form */
1041 Elf_Internal_Shdr **i_shdrp; /* Section header table, internal form */
1042 unsigned int count;
1043 size_t amt;
1044
1045 i_ehdrp = elf_elfheader (abfd);
1046 i_shdrp = elf_elfsections (abfd);
1047
1048 /* swap the header before spitting it out... */
1049
1050 #if DEBUG & 1
1051 elf_debug_file (i_ehdrp);
1052 #endif
1053 elf_swap_ehdr_out (abfd, i_ehdrp, &x_ehdr);
1054 amt = sizeof (x_ehdr);
1055 if (bfd_seek (abfd, (file_ptr) 0, SEEK_SET) != 0
1056 || bfd_bwrite (&x_ehdr, amt, abfd) != amt)
1057 return FALSE;
1058
1059 /* Some fields in the first section header handle overflow of ehdr
1060 fields. */
1061 if (i_ehdrp->e_phnum >= PN_XNUM)
1062 i_shdrp[0]->sh_info = i_ehdrp->e_phnum;
1063 if (i_ehdrp->e_shnum >= (SHN_LORESERVE & 0xffff))
1064 i_shdrp[0]->sh_size = i_ehdrp->e_shnum;
1065 if (i_ehdrp->e_shstrndx >= (SHN_LORESERVE & 0xffff))
1066 i_shdrp[0]->sh_link = i_ehdrp->e_shstrndx;
1067
1068 /* at this point we've concocted all the ELF sections... */
1069 if (_bfd_mul_overflow (i_ehdrp->e_shnum, sizeof (*x_shdrp), &amt))
1070 {
1071 bfd_set_error (bfd_error_no_memory);
1072 return FALSE;
1073 }
1074 x_shdrp = (Elf_External_Shdr *) bfd_alloc (abfd, amt);
1075 if (!x_shdrp)
1076 return FALSE;
1077
1078 for (count = 0; count < i_ehdrp->e_shnum; i_shdrp++, count++)
1079 {
1080 #if DEBUG & 2
1081 elf_debug_section (count, *i_shdrp);
1082 #endif
1083 elf_swap_shdr_out (abfd, *i_shdrp, x_shdrp + count);
1084 }
1085 amt = (bfd_size_type) i_ehdrp->e_shnum * sizeof (*x_shdrp);
1086 if (bfd_seek (abfd, (file_ptr) i_ehdrp->e_shoff, SEEK_SET) != 0
1087 || bfd_bwrite (x_shdrp, amt, abfd) != amt)
1088 return FALSE;
1089
1090 /* need to dump the string table too... */
1091
1092 return TRUE;
1093 }
1094
1095 bfd_boolean
1096 elf_checksum_contents (bfd *abfd,
1097 void (*process) (const void *, size_t, void *),
1098 void *arg)
1099 {
1100 Elf_Internal_Ehdr *i_ehdrp = elf_elfheader (abfd);
1101 Elf_Internal_Shdr **i_shdrp = elf_elfsections (abfd);
1102 Elf_Internal_Phdr *i_phdrp = elf_tdata (abfd)->phdr;
1103 unsigned int count, num;
1104
1105 {
1106 Elf_External_Ehdr x_ehdr;
1107 Elf_Internal_Ehdr i_ehdr;
1108
1109 i_ehdr = *i_ehdrp;
1110 i_ehdr.e_phoff = i_ehdr.e_shoff = 0;
1111 elf_swap_ehdr_out (abfd, &i_ehdr, &x_ehdr);
1112 (*process) (&x_ehdr, sizeof x_ehdr, arg);
1113 }
1114
1115 num = i_ehdrp->e_phnum;
1116 for (count = 0; count < num; count++)
1117 {
1118 Elf_External_Phdr x_phdr;
1119 elf_swap_phdr_out (abfd, &i_phdrp[count], &x_phdr);
1120 (*process) (&x_phdr, sizeof x_phdr, arg);
1121 }
1122
1123 num = elf_numsections (abfd);
1124 for (count = 0; count < num; count++)
1125 {
1126 Elf_Internal_Shdr i_shdr;
1127 Elf_External_Shdr x_shdr;
1128 bfd_byte *contents, *free_contents;
1129
1130 i_shdr = *i_shdrp[count];
1131 i_shdr.sh_offset = 0;
1132
1133 elf_swap_shdr_out (abfd, &i_shdr, &x_shdr);
1134 (*process) (&x_shdr, sizeof x_shdr, arg);
1135
1136 /* Process the section's contents, if it has some.
1137 PR ld/12451: Read them in if necessary. */
1138 if (i_shdr.sh_type == SHT_NOBITS)
1139 continue;
1140 free_contents = NULL;
1141 contents = i_shdr.contents;
1142 if (contents == NULL)
1143 {
1144 asection *sec;
1145
1146 sec = bfd_section_from_elf_index (abfd, count);
1147 if (sec != NULL)
1148 {
1149 contents = sec->contents;
1150 if (contents == NULL)
1151 {
1152 /* Force rereading from file. */
1153 sec->flags &= ~SEC_IN_MEMORY;
1154 if (!bfd_malloc_and_get_section (abfd, sec, &free_contents))
1155 continue;
1156 contents = free_contents;
1157 }
1158 }
1159 }
1160 if (contents != NULL)
1161 {
1162 (*process) (contents, i_shdr.sh_size, arg);
1163 free (free_contents);
1164 }
1165 }
1166
1167 return TRUE;
1168 }
1169
1170 long
1171 elf_slurp_symbol_table (bfd *abfd, asymbol **symptrs, bfd_boolean dynamic)
1172 {
1173 Elf_Internal_Shdr *hdr;
1174 Elf_Internal_Shdr *verhdr;
1175 unsigned long symcount; /* Number of external ELF symbols */
1176 elf_symbol_type *sym; /* Pointer to current bfd symbol */
1177 elf_symbol_type *symbase; /* Buffer for generated bfd symbols */
1178 Elf_Internal_Sym *isym;
1179 Elf_Internal_Sym *isymend;
1180 Elf_Internal_Sym *isymbuf = NULL;
1181 Elf_External_Versym *xver;
1182 Elf_External_Versym *xverbuf = NULL;
1183 const struct elf_backend_data *ebd;
1184 size_t amt;
1185
1186 /* Read each raw ELF symbol, converting from external ELF form to
1187 internal ELF form, and then using the information to create a
1188 canonical bfd symbol table entry.
1189
1190 Note that we allocate the initial bfd canonical symbol buffer
1191 based on a one-to-one mapping of the ELF symbols to canonical
1192 symbols. We actually use all the ELF symbols, so there will be no
1193 space left over at the end. When we have all the symbols, we
1194 build the caller's pointer vector. */
1195
1196 if (! dynamic)
1197 {
1198 hdr = &elf_tdata (abfd)->symtab_hdr;
1199 verhdr = NULL;
1200 }
1201 else
1202 {
1203 hdr = &elf_tdata (abfd)->dynsymtab_hdr;
1204 if (elf_dynversym (abfd) == 0)
1205 verhdr = NULL;
1206 else
1207 verhdr = &elf_tdata (abfd)->dynversym_hdr;
1208 if ((elf_dynverdef (abfd) != 0
1209 && elf_tdata (abfd)->verdef == NULL)
1210 || (elf_dynverref (abfd) != 0
1211 && elf_tdata (abfd)->verref == NULL))
1212 {
1213 if (!_bfd_elf_slurp_version_tables (abfd, FALSE))
1214 return -1;
1215 }
1216 }
1217
1218 ebd = get_elf_backend_data (abfd);
1219 symcount = hdr->sh_size / sizeof (Elf_External_Sym);
1220 if (symcount == 0)
1221 sym = symbase = NULL;
1222 else
1223 {
1224 isymbuf = bfd_elf_get_elf_syms (abfd, hdr, symcount, 0,
1225 NULL, NULL, NULL);
1226 if (isymbuf == NULL)
1227 return -1;
1228
1229 if (_bfd_mul_overflow (symcount, sizeof (elf_symbol_type), &amt))
1230 {
1231 bfd_set_error (bfd_error_file_too_big);
1232 goto error_return;
1233 }
1234 symbase = (elf_symbol_type *) bfd_zalloc (abfd, amt);
1235 if (symbase == (elf_symbol_type *) NULL)
1236 goto error_return;
1237
1238 /* Read the raw ELF version symbol information. */
1239 if (verhdr != NULL
1240 && verhdr->sh_size / sizeof (Elf_External_Versym) != symcount)
1241 {
1242 _bfd_error_handler
1243 /* xgettext:c-format */
1244 (_("%pB: version count (%" PRId64 ")"
1245 " does not match symbol count (%ld)"),
1246 abfd,
1247 (int64_t) (verhdr->sh_size / sizeof (Elf_External_Versym)),
1248 symcount);
1249
1250 /* Slurp in the symbols without the version information,
1251 since that is more helpful than just quitting. */
1252 verhdr = NULL;
1253 }
1254
1255 if (verhdr != NULL)
1256 {
1257 if (bfd_seek (abfd, verhdr->sh_offset, SEEK_SET) != 0)
1258 goto error_return;
1259 xverbuf = (Elf_External_Versym *)
1260 _bfd_malloc_and_read (abfd, verhdr->sh_size, verhdr->sh_size);
1261 if (xverbuf == NULL && verhdr->sh_size != 0)
1262 goto error_return;
1263 }
1264
1265 /* Skip first symbol, which is a null dummy. */
1266 xver = xverbuf;
1267 if (xver != NULL)
1268 ++xver;
1269 isymend = isymbuf + symcount;
1270 for (isym = isymbuf + 1, sym = symbase; isym < isymend; isym++, sym++)
1271 {
1272 memcpy (&sym->internal_elf_sym, isym, sizeof (Elf_Internal_Sym));
1273
1274 sym->symbol.the_bfd = abfd;
1275 sym->symbol.name = bfd_elf_sym_name (abfd, hdr, isym, NULL);
1276 sym->symbol.value = isym->st_value;
1277
1278 if (isym->st_shndx == SHN_UNDEF)
1279 {
1280 sym->symbol.section = bfd_und_section_ptr;
1281 }
1282 else if (isym->st_shndx == SHN_ABS)
1283 {
1284 sym->symbol.section = bfd_abs_section_ptr;
1285 }
1286 else if (isym->st_shndx == SHN_COMMON)
1287 {
1288 sym->symbol.section = bfd_com_section_ptr;
1289 if ((abfd->flags & BFD_PLUGIN) != 0)
1290 {
1291 asection *xc = bfd_get_section_by_name (abfd, "COMMON");
1292
1293 if (xc == NULL)
1294 {
1295 flagword flags = (SEC_ALLOC | SEC_IS_COMMON | SEC_KEEP
1296 | SEC_EXCLUDE);
1297 xc = bfd_make_section_with_flags (abfd, "COMMON", flags);
1298 if (xc == NULL)
1299 goto error_return;
1300 }
1301 sym->symbol.section = xc;
1302 }
1303 /* Elf puts the alignment into the `value' field, and
1304 the size into the `size' field. BFD wants to see the
1305 size in the value field, and doesn't care (at the
1306 moment) about the alignment. */
1307 sym->symbol.value = isym->st_size;
1308 }
1309 else
1310 {
1311 sym->symbol.section
1312 = bfd_section_from_elf_index (abfd, isym->st_shndx);
1313 if (sym->symbol.section == NULL)
1314 {
1315 /* This symbol is in a section for which we did not
1316 create a BFD section. Just use bfd_abs_section,
1317 although it is wrong. FIXME. Note - there is
1318 code in elf.c:swap_out_syms that calls
1319 symbol_section_index() in the elf backend for
1320 cases like this. */
1321 sym->symbol.section = bfd_abs_section_ptr;
1322 }
1323 }
1324
1325 /* If this is a relocatable file, then the symbol value is
1326 already section relative. */
1327 if ((abfd->flags & (EXEC_P | DYNAMIC)) != 0)
1328 sym->symbol.value -= sym->symbol.section->vma;
1329
1330 switch (ELF_ST_BIND (isym->st_info))
1331 {
1332 case STB_LOCAL:
1333 sym->symbol.flags |= BSF_LOCAL;
1334 break;
1335 case STB_GLOBAL:
1336 if (isym->st_shndx != SHN_UNDEF && isym->st_shndx != SHN_COMMON)
1337 sym->symbol.flags |= BSF_GLOBAL;
1338 break;
1339 case STB_WEAK:
1340 sym->symbol.flags |= BSF_WEAK;
1341 break;
1342 case STB_GNU_UNIQUE:
1343 sym->symbol.flags |= BSF_GNU_UNIQUE;
1344 break;
1345 }
1346
1347 switch (ELF_ST_TYPE (isym->st_info))
1348 {
1349 case STT_SECTION:
1350 sym->symbol.flags |= BSF_SECTION_SYM | BSF_DEBUGGING;
1351 break;
1352 case STT_FILE:
1353 sym->symbol.flags |= BSF_FILE | BSF_DEBUGGING;
1354 break;
1355 case STT_FUNC:
1356 sym->symbol.flags |= BSF_FUNCTION;
1357 break;
1358 case STT_COMMON:
1359 /* FIXME: Do we have to put the size field into the value field
1360 as we do with symbols in SHN_COMMON sections (see above) ? */
1361 sym->symbol.flags |= BSF_ELF_COMMON;
1362 /* Fall through. */
1363 case STT_OBJECT:
1364 sym->symbol.flags |= BSF_OBJECT;
1365 break;
1366 case STT_TLS:
1367 sym->symbol.flags |= BSF_THREAD_LOCAL;
1368 break;
1369 case STT_RELC:
1370 sym->symbol.flags |= BSF_RELC;
1371 break;
1372 case STT_SRELC:
1373 sym->symbol.flags |= BSF_SRELC;
1374 break;
1375 case STT_GNU_IFUNC:
1376 sym->symbol.flags |= BSF_GNU_INDIRECT_FUNCTION;
1377 break;
1378 }
1379
1380 if (dynamic)
1381 sym->symbol.flags |= BSF_DYNAMIC;
1382
1383 if (xver != NULL)
1384 {
1385 Elf_Internal_Versym iversym;
1386
1387 _bfd_elf_swap_versym_in (abfd, xver, &iversym);
1388 sym->version = iversym.vs_vers;
1389 xver++;
1390 }
1391
1392 /* Do some backend-specific processing on this symbol. */
1393 if (ebd->elf_backend_symbol_processing)
1394 (*ebd->elf_backend_symbol_processing) (abfd, &sym->symbol);
1395 }
1396 }
1397
1398 /* Do some backend-specific processing on this symbol table. */
1399 if (ebd->elf_backend_symbol_table_processing)
1400 (*ebd->elf_backend_symbol_table_processing) (abfd, symbase, symcount);
1401
1402 /* We rely on the zalloc to clear out the final symbol entry. */
1403
1404 symcount = sym - symbase;
1405
1406 /* Fill in the user's symbol pointer vector if needed. */
1407 if (symptrs)
1408 {
1409 long l = symcount;
1410
1411 sym = symbase;
1412 while (l-- > 0)
1413 {
1414 *symptrs++ = &sym->symbol;
1415 sym++;
1416 }
1417 *symptrs = 0; /* Final null pointer */
1418 }
1419
1420 free (xverbuf);
1421 if (hdr->contents != (unsigned char *) isymbuf)
1422 free (isymbuf);
1423 return symcount;
1424
1425 error_return:
1426 free (xverbuf);
1427 if (hdr->contents != (unsigned char *) isymbuf)
1428 free (isymbuf);
1429 return -1;
1430 }
1431
1432 /* Read relocations for ASECT from REL_HDR. There are RELOC_COUNT of
1433 them. */
1434
1435 static bfd_boolean
1436 elf_slurp_reloc_table_from_section (bfd *abfd,
1437 asection *asect,
1438 Elf_Internal_Shdr *rel_hdr,
1439 bfd_size_type reloc_count,
1440 arelent *relents,
1441 asymbol **symbols,
1442 bfd_boolean dynamic)
1443 {
1444 const struct elf_backend_data * const ebd = get_elf_backend_data (abfd);
1445 void *allocated = NULL;
1446 bfd_byte *native_relocs;
1447 arelent *relent;
1448 unsigned int i;
1449 int entsize;
1450 unsigned int symcount;
1451
1452 if (bfd_seek (abfd, rel_hdr->sh_offset, SEEK_SET) != 0)
1453 return FALSE;
1454 allocated = _bfd_malloc_and_read (abfd, rel_hdr->sh_size, rel_hdr->sh_size);
1455 if (allocated == NULL)
1456 return FALSE;
1457
1458 native_relocs = (bfd_byte *) allocated;
1459
1460 entsize = rel_hdr->sh_entsize;
1461 BFD_ASSERT (entsize == sizeof (Elf_External_Rel)
1462 || entsize == sizeof (Elf_External_Rela));
1463
1464 if (dynamic)
1465 symcount = bfd_get_dynamic_symcount (abfd);
1466 else
1467 symcount = bfd_get_symcount (abfd);
1468
1469 for (i = 0, relent = relents;
1470 i < reloc_count;
1471 i++, relent++, native_relocs += entsize)
1472 {
1473 bfd_boolean res;
1474 Elf_Internal_Rela rela;
1475
1476 if (entsize == sizeof (Elf_External_Rela))
1477 elf_swap_reloca_in (abfd, native_relocs, &rela);
1478 else
1479 elf_swap_reloc_in (abfd, native_relocs, &rela);
1480
1481 /* The address of an ELF reloc is section relative for an object
1482 file, and absolute for an executable file or shared library.
1483 The address of a normal BFD reloc is always section relative,
1484 and the address of a dynamic reloc is absolute.. */
1485 if ((abfd->flags & (EXEC_P | DYNAMIC)) == 0 || dynamic)
1486 relent->address = rela.r_offset;
1487 else
1488 relent->address = rela.r_offset - asect->vma;
1489
1490 if (ELF_R_SYM (rela.r_info) == STN_UNDEF)
1491 /* FIXME: This and the error case below mean that we have a
1492 symbol on relocs that is not elf_symbol_type. */
1493 relent->sym_ptr_ptr = bfd_abs_section_ptr->symbol_ptr_ptr;
1494 else if (ELF_R_SYM (rela.r_info) > symcount)
1495 {
1496 _bfd_error_handler
1497 /* xgettext:c-format */
1498 (_("%pB(%pA): relocation %d has invalid symbol index %ld"),
1499 abfd, asect, i, (long) ELF_R_SYM (rela.r_info));
1500 bfd_set_error (bfd_error_bad_value);
1501 relent->sym_ptr_ptr = bfd_abs_section_ptr->symbol_ptr_ptr;
1502 }
1503 else
1504 {
1505 asymbol **ps;
1506
1507 ps = symbols + ELF_R_SYM (rela.r_info) - 1;
1508
1509 relent->sym_ptr_ptr = ps;
1510 }
1511
1512 relent->addend = rela.r_addend;
1513
1514 if ((entsize == sizeof (Elf_External_Rela)
1515 && ebd->elf_info_to_howto != NULL)
1516 || ebd->elf_info_to_howto_rel == NULL)
1517 res = ebd->elf_info_to_howto (abfd, relent, &rela);
1518 else
1519 res = ebd->elf_info_to_howto_rel (abfd, relent, &rela);
1520
1521 if (! res || relent->howto == NULL)
1522 goto error_return;
1523 }
1524
1525 free (allocated);
1526 return TRUE;
1527
1528 error_return:
1529 free (allocated);
1530 return FALSE;
1531 }
1532
1533 /* Read in and swap the external relocs. */
1534
1535 bfd_boolean
1536 elf_slurp_reloc_table (bfd *abfd,
1537 asection *asect,
1538 asymbol **symbols,
1539 bfd_boolean dynamic)
1540 {
1541 const struct elf_backend_data * const bed = get_elf_backend_data (abfd);
1542 struct bfd_elf_section_data * const d = elf_section_data (asect);
1543 Elf_Internal_Shdr *rel_hdr;
1544 Elf_Internal_Shdr *rel_hdr2;
1545 bfd_size_type reloc_count;
1546 bfd_size_type reloc_count2;
1547 arelent *relents;
1548 size_t amt;
1549
1550 if (asect->relocation != NULL)
1551 return TRUE;
1552
1553 if (! dynamic)
1554 {
1555 if ((asect->flags & SEC_RELOC) == 0
1556 || asect->reloc_count == 0)
1557 return TRUE;
1558
1559 rel_hdr = d->rel.hdr;
1560 reloc_count = rel_hdr ? NUM_SHDR_ENTRIES (rel_hdr) : 0;
1561 rel_hdr2 = d->rela.hdr;
1562 reloc_count2 = rel_hdr2 ? NUM_SHDR_ENTRIES (rel_hdr2) : 0;
1563
1564 /* PR 17512: file: 0b4f81b7. */
1565 if (asect->reloc_count != reloc_count + reloc_count2)
1566 return FALSE;
1567 BFD_ASSERT ((rel_hdr && asect->rel_filepos == rel_hdr->sh_offset)
1568 || (rel_hdr2 && asect->rel_filepos == rel_hdr2->sh_offset));
1569
1570 }
1571 else
1572 {
1573 /* Note that ASECT->RELOC_COUNT tends not to be accurate in this
1574 case because relocations against this section may use the
1575 dynamic symbol table, and in that case bfd_section_from_shdr
1576 in elf.c does not update the RELOC_COUNT. */
1577 if (asect->size == 0)
1578 return TRUE;
1579
1580 rel_hdr = &d->this_hdr;
1581 reloc_count = NUM_SHDR_ENTRIES (rel_hdr);
1582 rel_hdr2 = NULL;
1583 reloc_count2 = 0;
1584 }
1585
1586 if (_bfd_mul_overflow (reloc_count + reloc_count2, sizeof (arelent), &amt))
1587 {
1588 bfd_set_error (bfd_error_file_too_big);
1589 return FALSE;
1590 }
1591 relents = (arelent *) bfd_alloc (abfd, amt);
1592 if (relents == NULL)
1593 return FALSE;
1594
1595 if (rel_hdr
1596 && !elf_slurp_reloc_table_from_section (abfd, asect,
1597 rel_hdr, reloc_count,
1598 relents,
1599 symbols, dynamic))
1600 return FALSE;
1601
1602 if (rel_hdr2
1603 && !elf_slurp_reloc_table_from_section (abfd, asect,
1604 rel_hdr2, reloc_count2,
1605 relents + reloc_count,
1606 symbols, dynamic))
1607 return FALSE;
1608
1609 if (!bed->slurp_secondary_relocs (abfd, asect, symbols, dynamic))
1610 return FALSE;
1611
1612 asect->relocation = relents;
1613 return TRUE;
1614 }
1615
1616 #if DEBUG & 2
1617 static void
1618 elf_debug_section (int num, Elf_Internal_Shdr *hdr)
1619 {
1620 fprintf (stderr, "\nSection#%d '%s' 0x%.8lx\n", num,
1621 hdr->bfd_section != NULL ? hdr->bfd_section->name : "",
1622 (long) hdr);
1623 fprintf (stderr,
1624 "sh_name = %ld\tsh_type = %ld\tsh_flags = %ld\n",
1625 (long) hdr->sh_name,
1626 (long) hdr->sh_type,
1627 (long) hdr->sh_flags);
1628 fprintf (stderr,
1629 "sh_addr = %ld\tsh_offset = %ld\tsh_size = %ld\n",
1630 (long) hdr->sh_addr,
1631 (long) hdr->sh_offset,
1632 (long) hdr->sh_size);
1633 fprintf (stderr,
1634 "sh_link = %ld\tsh_info = %ld\tsh_addralign = %ld\n",
1635 (long) hdr->sh_link,
1636 (long) hdr->sh_info,
1637 (long) hdr->sh_addralign);
1638 fprintf (stderr, "sh_entsize = %ld\n",
1639 (long) hdr->sh_entsize);
1640 fflush (stderr);
1641 }
1642 #endif
1643
1644 #if DEBUG & 1
1645 static void
1646 elf_debug_file (Elf_Internal_Ehdr *ehdrp)
1647 {
1648 fprintf (stderr, "e_entry = 0x%.8lx\n", (long) ehdrp->e_entry);
1649 fprintf (stderr, "e_phoff = %ld\n", (long) ehdrp->e_phoff);
1650 fprintf (stderr, "e_phnum = %ld\n", (long) ehdrp->e_phnum);
1651 fprintf (stderr, "e_phentsize = %ld\n", (long) ehdrp->e_phentsize);
1652 fprintf (stderr, "e_shoff = %ld\n", (long) ehdrp->e_shoff);
1653 fprintf (stderr, "e_shnum = %ld\n", (long) ehdrp->e_shnum);
1654 fprintf (stderr, "e_shentsize = %ld\n", (long) ehdrp->e_shentsize);
1655 }
1656 #endif
1657 \f
1658 /* Create a new BFD as if by bfd_openr. Rather than opening a file,
1659 reconstruct an ELF file by reading the segments out of remote
1660 memory based on the ELF file header at EHDR_VMA and the ELF program
1661 headers it points to. If non-zero, SIZE is the known extent of the
1662 object. If not null, *LOADBASEP is filled in with the difference
1663 between the VMAs from which the segments were read, and the VMAs
1664 the file headers (and hence BFD's idea of each section's VMA) put
1665 them at.
1666
1667 The function TARGET_READ_MEMORY is called to copy LEN bytes from
1668 the remote memory at target address VMA into the local buffer at
1669 MYADDR; it should return zero on success or an `errno' code on
1670 failure. TEMPL must be a BFD for a target with the word size and
1671 byte order found in the remote memory. */
1672
1673 bfd *
1674 NAME(_bfd_elf,bfd_from_remote_memory)
1675 (bfd *templ,
1676 bfd_vma ehdr_vma /* Bytes. */,
1677 bfd_size_type size /* Octets. */,
1678 bfd_vma *loadbasep /* Bytes. */,
1679 int (*target_read_memory) (bfd_vma, bfd_byte *, bfd_size_type))
1680 /* (Bytes , , octets ). */
1681 {
1682 Elf_External_Ehdr x_ehdr; /* Elf file header, external form */
1683 Elf_Internal_Ehdr i_ehdr; /* Elf file header, internal form */
1684 Elf_External_Phdr *x_phdrs;
1685 Elf_Internal_Phdr *i_phdrs, *last_phdr, *first_phdr;
1686 bfd *nbfd;
1687 struct bfd_in_memory *bim;
1688 bfd_byte *contents;
1689 int err;
1690 unsigned int i;
1691 bfd_vma high_offset;
1692 bfd_vma shdr_end;
1693 bfd_vma loadbase; /* Bytes. */
1694 size_t amt;
1695 unsigned int opb = bfd_octets_per_byte (templ, NULL);
1696
1697 /* Read in the ELF header in external format. */
1698 err = target_read_memory (ehdr_vma, (bfd_byte *) &x_ehdr, sizeof x_ehdr);
1699 if (err)
1700 {
1701 bfd_set_error (bfd_error_system_call);
1702 errno = err;
1703 return NULL;
1704 }
1705
1706 /* Now check to see if we have a valid ELF file, and one that BFD can
1707 make use of. The magic number must match, the address size ('class')
1708 and byte-swapping must match our XVEC entry. */
1709
1710 if (! elf_file_p (&x_ehdr)
1711 || x_ehdr.e_ident[EI_VERSION] != EV_CURRENT
1712 || x_ehdr.e_ident[EI_CLASS] != ELFCLASS)
1713 {
1714 bfd_set_error (bfd_error_wrong_format);
1715 return NULL;
1716 }
1717
1718 /* Check that file's byte order matches xvec's */
1719 switch (x_ehdr.e_ident[EI_DATA])
1720 {
1721 case ELFDATA2MSB: /* Big-endian */
1722 if (! bfd_header_big_endian (templ))
1723 {
1724 bfd_set_error (bfd_error_wrong_format);
1725 return NULL;
1726 }
1727 break;
1728 case ELFDATA2LSB: /* Little-endian */
1729 if (! bfd_header_little_endian (templ))
1730 {
1731 bfd_set_error (bfd_error_wrong_format);
1732 return NULL;
1733 }
1734 break;
1735 case ELFDATANONE: /* No data encoding specified */
1736 default: /* Unknown data encoding specified */
1737 bfd_set_error (bfd_error_wrong_format);
1738 return NULL;
1739 }
1740
1741 elf_swap_ehdr_in (templ, &x_ehdr, &i_ehdr);
1742
1743 /* The file header tells where to find the program headers.
1744 These are what we use to actually choose what to read. */
1745
1746 if (i_ehdr.e_phentsize != sizeof (Elf_External_Phdr) || i_ehdr.e_phnum == 0)
1747 {
1748 bfd_set_error (bfd_error_wrong_format);
1749 return NULL;
1750 }
1751
1752 if (_bfd_mul_overflow (i_ehdr.e_phnum,
1753 sizeof (*x_phdrs) + sizeof (*i_phdrs), &amt))
1754 {
1755 bfd_set_error (bfd_error_file_too_big);
1756 return NULL;
1757 }
1758 x_phdrs = (Elf_External_Phdr *) bfd_malloc (amt);
1759 if (x_phdrs == NULL)
1760 return NULL;
1761 err = target_read_memory (ehdr_vma + i_ehdr.e_phoff, (bfd_byte *) x_phdrs,
1762 i_ehdr.e_phnum * sizeof x_phdrs[0]);
1763 if (err)
1764 {
1765 free (x_phdrs);
1766 bfd_set_error (bfd_error_system_call);
1767 errno = err;
1768 return NULL;
1769 }
1770 i_phdrs = (Elf_Internal_Phdr *) &x_phdrs[i_ehdr.e_phnum];
1771
1772 high_offset = 0;
1773 loadbase = 0;
1774 first_phdr = NULL;
1775 last_phdr = NULL;
1776 for (i = 0; i < i_ehdr.e_phnum; ++i)
1777 {
1778 elf_swap_phdr_in (templ, &x_phdrs[i], &i_phdrs[i]);
1779 if (i_phdrs[i].p_type == PT_LOAD)
1780 {
1781 bfd_vma segment_end = i_phdrs[i].p_offset + i_phdrs[i].p_filesz;
1782
1783 if (segment_end > high_offset)
1784 {
1785 high_offset = segment_end;
1786 last_phdr = &i_phdrs[i];
1787 }
1788
1789 /* If this program header covers offset zero, where the file
1790 header sits, then we can figure out the loadbase. */
1791 if (first_phdr == NULL)
1792 {
1793 bfd_vma p_offset = i_phdrs[i].p_offset; /* Octets. */
1794 bfd_vma p_vaddr = i_phdrs[i].p_vaddr; /* Octets. */
1795
1796 if (i_phdrs[i].p_align > 1)
1797 {
1798 p_offset &= -(i_phdrs[i].p_align * opb);
1799 p_vaddr &= -(i_phdrs[i].p_align * opb);
1800 }
1801 if (p_offset == 0)
1802 {
1803 loadbase = ehdr_vma - p_vaddr / opb;
1804 first_phdr = &i_phdrs[i];
1805 }
1806 }
1807 }
1808 }
1809 if (high_offset == 0)
1810 {
1811 /* There were no PT_LOAD segments, so we don't have anything to read. */
1812 free (x_phdrs);
1813 bfd_set_error (bfd_error_wrong_format);
1814 return NULL;
1815 }
1816
1817 shdr_end = 0;
1818 if (i_ehdr.e_shoff != 0 && i_ehdr.e_shnum != 0 && i_ehdr.e_shentsize != 0)
1819 {
1820 shdr_end = i_ehdr.e_shoff + i_ehdr.e_shnum * i_ehdr.e_shentsize;
1821
1822 if (last_phdr->p_filesz != last_phdr->p_memsz)
1823 {
1824 /* If the last PT_LOAD header has a bss area then ld.so will
1825 have cleared anything past p_filesz, zapping the section
1826 headers. */
1827 }
1828 else if (size >= shdr_end)
1829 high_offset = size;
1830 else
1831 {
1832 bfd_vma page_size = get_elf_backend_data (templ)->minpagesize;
1833 bfd_vma segment_end = last_phdr->p_offset + last_phdr->p_filesz;
1834
1835 /* Assume we loaded full pages, allowing us to sometimes see
1836 section headers. */
1837 if (page_size > 1 && shdr_end > segment_end)
1838 {
1839 bfd_vma page_end = (segment_end + page_size - 1) & -page_size;
1840
1841 if (page_end >= shdr_end)
1842 /* Whee, section headers covered. */
1843 high_offset = shdr_end;
1844 }
1845 }
1846 }
1847
1848 /* Now we know the size of the whole image we want read in. */
1849 contents = (bfd_byte *) bfd_zmalloc (high_offset);
1850 if (contents == NULL)
1851 {
1852 free (x_phdrs);
1853 return NULL;
1854 }
1855
1856 for (i = 0; i < i_ehdr.e_phnum; ++i)
1857 if (i_phdrs[i].p_type == PT_LOAD)
1858 {
1859 bfd_vma start = i_phdrs[i].p_offset; /* Octets. */
1860 bfd_vma end = start + i_phdrs[i].p_filesz; /* Octets. */
1861 bfd_vma vaddr = i_phdrs[i].p_vaddr; /* Octets. */
1862
1863 /* Extend the beginning of the first pt_load to cover file
1864 header and program headers, if we proved earlier that its
1865 aligned offset is 0. */
1866 if (first_phdr == &i_phdrs[i])
1867 {
1868 vaddr -= start;
1869 start = 0;
1870 }
1871 /* Extend the end of the last pt_load to cover section headers. */
1872 if (last_phdr == &i_phdrs[i])
1873 end = high_offset;
1874 err = target_read_memory (loadbase + vaddr / opb,
1875 contents + start, end - start);
1876 if (err)
1877 {
1878 free (x_phdrs);
1879 free (contents);
1880 bfd_set_error (bfd_error_system_call);
1881 errno = err;
1882 return NULL;
1883 }
1884 }
1885 free (x_phdrs);
1886
1887 /* If the segments visible in memory didn't include the section headers,
1888 then clear them from the file header. */
1889 if (high_offset < shdr_end)
1890 {
1891 memset (&x_ehdr.e_shoff, 0, sizeof x_ehdr.e_shoff);
1892 memset (&x_ehdr.e_shnum, 0, sizeof x_ehdr.e_shnum);
1893 memset (&x_ehdr.e_shstrndx, 0, sizeof x_ehdr.e_shstrndx);
1894 }
1895
1896 /* This will normally have been in the first PT_LOAD segment. But it
1897 conceivably could be missing, and we might have just changed it. */
1898 memcpy (contents, &x_ehdr, sizeof x_ehdr);
1899
1900 /* Now we have a memory image of the ELF file contents. Make a BFD. */
1901 bim = (struct bfd_in_memory *) bfd_malloc (sizeof (struct bfd_in_memory));
1902 if (bim == NULL)
1903 {
1904 free (contents);
1905 return NULL;
1906 }
1907 nbfd = _bfd_new_bfd ();
1908 if (nbfd == NULL
1909 || !bfd_set_filename (nbfd, "<in-memory>"))
1910 {
1911 free (bim);
1912 free (contents);
1913 return NULL;
1914 }
1915 nbfd->xvec = templ->xvec;
1916 bim->size = high_offset;
1917 bim->buffer = contents;
1918 nbfd->iostream = bim;
1919 nbfd->flags = BFD_IN_MEMORY;
1920 nbfd->iovec = &_bfd_memory_iovec;
1921 nbfd->origin = 0;
1922 nbfd->direction = read_direction;
1923 nbfd->mtime = time (NULL);
1924 nbfd->mtime_set = TRUE;
1925
1926 if (loadbasep)
1927 *loadbasep = loadbase;
1928 return nbfd;
1929 }
1930
1931 /* Function for ELF_R_INFO. */
1932
1933 bfd_vma
1934 NAME(elf,r_info) (bfd_vma sym, bfd_vma type)
1935 {
1936 return ELF_R_INFO (sym, type);
1937 }
1938
1939 /* Function for ELF_R_SYM. */
1940
1941 bfd_vma
1942 NAME(elf,r_sym) (bfd_vma r_info)
1943 {
1944 return ELF_R_SYM (r_info);
1945 }
1946 \f
1947 #include "elfcore.h"
1948 \f
1949 /* Size-dependent data and functions. */
1950 const struct elf_size_info NAME(_bfd_elf,size_info) = {
1951 sizeof (Elf_External_Ehdr),
1952 sizeof (Elf_External_Phdr),
1953 sizeof (Elf_External_Shdr),
1954 sizeof (Elf_External_Rel),
1955 sizeof (Elf_External_Rela),
1956 sizeof (Elf_External_Sym),
1957 sizeof (Elf_External_Dyn),
1958 sizeof (Elf_External_Note),
1959 4,
1960 1,
1961 ARCH_SIZE, LOG_FILE_ALIGN,
1962 ELFCLASS, EV_CURRENT,
1963 elf_write_out_phdrs,
1964 elf_write_shdrs_and_ehdr,
1965 elf_checksum_contents,
1966 elf_write_relocs,
1967 elf_swap_symbol_in,
1968 elf_swap_symbol_out,
1969 elf_slurp_reloc_table,
1970 elf_slurp_symbol_table,
1971 elf_swap_dyn_in,
1972 elf_swap_dyn_out,
1973 elf_swap_reloc_in,
1974 elf_swap_reloc_out,
1975 elf_swap_reloca_in,
1976 elf_swap_reloca_out
1977 };