1 /* elfedit.c -- Update the ELF header of an ELF format file
2 Copyright (C) 2010-2014 Free Software Foundation, Inc.
4 This file is part of GNU Binutils.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA
25 /* Define BFD64 here, even if our default architecture is 32 bit ELF
26 as this will allow us to read in and parse 64bit and 32bit ELF files.
27 Only do this if we believe that the compiler can support a 64 bit
28 data type. For now we only rely on GCC being able to do this. */
36 #include "elf/common.h"
37 #include "elf/external.h"
38 #include "elf/internal.h"
41 #include "libiberty.h"
42 #include "safe-ctype.h"
43 #include "filenames.h"
45 char * program_name = "elfedit";
46 static long archive_file_offset;
47 static unsigned long archive_file_size;
48 static Elf_Internal_Ehdr elf_header;
49 static Elf32_External_Ehdr ehdr32;
50 static Elf64_External_Ehdr ehdr64;
51 static int input_elf_machine = -1;
52 static int output_elf_machine = -1;
53 static int input_elf_type = -1;
54 static int output_elf_type = -1;
55 static int input_elf_osabi = -1;
56 static int output_elf_osabi = -1;
57 static int input_elf_class = -1;
60 update_elf_header (const char *file_name, FILE *file)
62 int class, machine, type, status, osabi;
64 if (elf_header.e_ident[EI_MAG0] != ELFMAG0
65 || elf_header.e_ident[EI_MAG1] != ELFMAG1
66 || elf_header.e_ident[EI_MAG2] != ELFMAG2
67 || elf_header.e_ident[EI_MAG3] != ELFMAG3)
70 (_("%s: Not an ELF file - wrong magic bytes at the start\n"),
75 if (elf_header.e_ident[EI_VERSION] != EV_CURRENT)
78 (_("%s: Unsupported EI_VERSION: %d is not %d\n"),
79 file_name, elf_header.e_ident[EI_VERSION],
84 /* Return if e_machine is the same as output_elf_machine. */
85 if (output_elf_machine == elf_header.e_machine)
88 class = elf_header.e_ident[EI_CLASS];
90 /* Skip if class doesn't match. */
91 if (input_elf_class != -1 && class != input_elf_class)
94 (_("%s: Unmatched EI_CLASS: %d is not %d\n"),
95 file_name, class, input_elf_class);
99 machine = elf_header.e_machine;
101 /* Skip if e_machine doesn't match. */
102 if (input_elf_machine != -1 && machine != input_elf_machine)
105 (_("%s: Unmatched e_machine: %d is not %d\n"),
106 file_name, machine, input_elf_machine);
110 type = elf_header.e_type;
112 /* Skip if e_type doesn't match. */
113 if (input_elf_type != -1 && type != input_elf_type)
116 (_("%s: Unmatched e_type: %d is not %d\n"),
117 file_name, type, input_elf_type);
121 osabi = elf_header.e_ident[EI_OSABI];
123 /* Skip if OSABI doesn't match. */
124 if (input_elf_osabi != -1 && osabi != input_elf_osabi)
127 (_("%s: Unmatched EI_OSABI: %d is not %d\n"),
128 file_name, osabi, input_elf_osabi);
132 /* Update e_machine, e_type and EI_OSABI. */
136 /* We should never get here. */
140 if (output_elf_machine != -1)
141 BYTE_PUT (ehdr32.e_machine, output_elf_machine);
142 if (output_elf_type != -1)
143 BYTE_PUT (ehdr32.e_type, output_elf_type);
144 if (output_elf_osabi != -1)
145 ehdr32.e_ident[EI_OSABI] = output_elf_osabi;
146 status = fwrite (&ehdr32, sizeof (ehdr32), 1, file) == 1;
149 if (output_elf_machine != -1)
150 BYTE_PUT (ehdr64.e_machine, output_elf_machine);
151 if (output_elf_type != -1)
152 BYTE_PUT (ehdr64.e_type, output_elf_type);
153 if (output_elf_osabi != -1)
154 ehdr64.e_ident[EI_OSABI] = output_elf_osabi;
155 status = fwrite (&ehdr64, sizeof (ehdr64), 1, file) == 1;
160 error (_("%s: Failed to update ELF header: %s\n"),
161 file_name, strerror (errno));
167 get_file_header (FILE * file)
169 /* Read in the identity array. */
170 if (fread (elf_header.e_ident, EI_NIDENT, 1, file) != 1)
173 /* Determine how to read the rest of the header. */
174 switch (elf_header.e_ident[EI_DATA])
176 default: /* fall through */
177 case ELFDATANONE: /* fall through */
179 byte_get = byte_get_little_endian;
180 byte_put = byte_put_little_endian;
183 byte_get = byte_get_big_endian;
184 byte_put = byte_put_big_endian;
188 /* Read in the rest of the header. For now we only support 32 bit
189 and 64 bit ELF files. */
190 switch (elf_header.e_ident[EI_CLASS])
193 error (_("Unsupported EI_CLASS: %d\n"),
194 elf_header.e_ident[EI_CLASS]);
198 if (fread (ehdr32.e_type, sizeof (ehdr32) - EI_NIDENT,
202 elf_header.e_type = BYTE_GET (ehdr32.e_type);
203 elf_header.e_machine = BYTE_GET (ehdr32.e_machine);
204 elf_header.e_version = BYTE_GET (ehdr32.e_version);
205 elf_header.e_entry = BYTE_GET (ehdr32.e_entry);
206 elf_header.e_phoff = BYTE_GET (ehdr32.e_phoff);
207 elf_header.e_shoff = BYTE_GET (ehdr32.e_shoff);
208 elf_header.e_flags = BYTE_GET (ehdr32.e_flags);
209 elf_header.e_ehsize = BYTE_GET (ehdr32.e_ehsize);
210 elf_header.e_phentsize = BYTE_GET (ehdr32.e_phentsize);
211 elf_header.e_phnum = BYTE_GET (ehdr32.e_phnum);
212 elf_header.e_shentsize = BYTE_GET (ehdr32.e_shentsize);
213 elf_header.e_shnum = BYTE_GET (ehdr32.e_shnum);
214 elf_header.e_shstrndx = BYTE_GET (ehdr32.e_shstrndx);
216 memcpy (&ehdr32, &elf_header, EI_NIDENT);
220 /* If we have been compiled with sizeof (bfd_vma) == 4, then
221 we will not be able to cope with the 64bit data found in
222 64 ELF files. Detect this now and abort before we start
223 overwriting things. */
224 if (sizeof (bfd_vma) < 8)
226 error (_("This executable has been built without support for a\n\
227 64 bit data type and so it cannot process 64 bit ELF files.\n"));
231 if (fread (ehdr64.e_type, sizeof (ehdr64) - EI_NIDENT,
235 elf_header.e_type = BYTE_GET (ehdr64.e_type);
236 elf_header.e_machine = BYTE_GET (ehdr64.e_machine);
237 elf_header.e_version = BYTE_GET (ehdr64.e_version);
238 elf_header.e_entry = BYTE_GET (ehdr64.e_entry);
239 elf_header.e_phoff = BYTE_GET (ehdr64.e_phoff);
240 elf_header.e_shoff = BYTE_GET (ehdr64.e_shoff);
241 elf_header.e_flags = BYTE_GET (ehdr64.e_flags);
242 elf_header.e_ehsize = BYTE_GET (ehdr64.e_ehsize);
243 elf_header.e_phentsize = BYTE_GET (ehdr64.e_phentsize);
244 elf_header.e_phnum = BYTE_GET (ehdr64.e_phnum);
245 elf_header.e_shentsize = BYTE_GET (ehdr64.e_shentsize);
246 elf_header.e_shnum = BYTE_GET (ehdr64.e_shnum);
247 elf_header.e_shstrndx = BYTE_GET (ehdr64.e_shstrndx);
249 memcpy (&ehdr64, &elf_header, EI_NIDENT);
255 /* Process one ELF object file according to the command line options.
256 This file may actually be stored in an archive. The file is
257 positioned at the start of the ELF object. */
260 process_object (const char *file_name, FILE *file)
262 /* Rememeber where we are. */
263 long offset = ftell (file);
265 if (! get_file_header (file))
267 error (_("%s: Failed to read ELF header\n"), file_name);
271 /* Go to the position of the ELF header. */
272 if (fseek (file, offset, SEEK_SET) != 0)
274 error (_("%s: Failed to seek to ELF header\n"), file_name);
277 if (! update_elf_header (file_name, file))
283 /* Process an ELF archive.
284 On entry the file is positioned just after the ARMAG string. */
287 process_archive (const char * file_name, FILE * file,
288 bfd_boolean is_thin_archive)
290 struct archive_info arch;
291 struct archive_info nested_arch;
295 /* The ARCH structure is used to hold information about this archive. */
296 arch.file_name = NULL;
298 arch.index_array = NULL;
299 arch.sym_table = NULL;
300 arch.longnames = NULL;
302 /* The NESTED_ARCH structure is used as a single-item cache of information
303 about a nested archive (when members of a thin archive reside within
304 another regular archive file). */
305 nested_arch.file_name = NULL;
306 nested_arch.file = NULL;
307 nested_arch.index_array = NULL;
308 nested_arch.sym_table = NULL;
309 nested_arch.longnames = NULL;
311 if (setup_archive (&arch, file_name, file, is_thin_archive, FALSE) != 0)
323 char * qualified_name;
325 /* Read the next archive header. */
326 if (fseek (file, arch.next_arhdr_offset, SEEK_SET) != 0)
328 error (_("%s: failed to seek to next archive header\n"),
332 got = fread (&arch.arhdr, 1, sizeof arch.arhdr, file);
333 if (got != sizeof arch.arhdr)
337 error (_("%s: failed to read archive header\n"),
342 if (memcmp (arch.arhdr.ar_fmag, ARFMAG, 2) != 0)
344 error (_("%s: did not find a valid archive header\n"),
350 arch.next_arhdr_offset += sizeof arch.arhdr;
352 archive_file_size = strtoul (arch.arhdr.ar_size, NULL, 10);
353 if (archive_file_size & 01)
356 name = get_archive_member_name (&arch, &nested_arch);
359 error (_("%s: bad archive file name\n"), file_name);
363 namelen = strlen (name);
365 qualified_name = make_qualified_name (&arch, &nested_arch, name);
366 if (qualified_name == NULL)
368 error (_("%s: bad archive file name\n"), file_name);
373 if (is_thin_archive && arch.nested_member_origin == 0)
375 /* This is a proxy for an external member of a thin archive. */
377 char *member_file_name = adjust_relative_path (file_name,
379 if (member_file_name == NULL)
385 member_file = fopen (member_file_name, "r+b");
386 if (member_file == NULL)
388 error (_("Input file '%s' is not readable\n"),
390 free (member_file_name);
395 archive_file_offset = arch.nested_member_origin;
397 ret |= process_object (qualified_name, member_file);
399 fclose (member_file);
400 free (member_file_name);
402 else if (is_thin_archive)
404 /* This is a proxy for a member of a nested archive. */
405 archive_file_offset = arch.nested_member_origin + sizeof arch.arhdr;
407 /* The nested archive file will have been opened and setup by
408 get_archive_member_name. */
409 if (fseek (nested_arch.file, archive_file_offset,
412 error (_("%s: failed to seek to archive member\n"),
413 nested_arch.file_name);
418 ret |= process_object (qualified_name, nested_arch.file);
422 archive_file_offset = arch.next_arhdr_offset;
423 arch.next_arhdr_offset += archive_file_size;
425 ret |= process_object (qualified_name, file);
428 free (qualified_name);
432 if (nested_arch.file != NULL)
433 fclose (nested_arch.file);
434 release_archive (&nested_arch);
435 release_archive (&arch);
441 check_file (const char *file_name, struct stat *statbuf_p)
445 if (statbuf_p == NULL)
446 statbuf_p = &statbuf;
448 if (stat (file_name, statbuf_p) < 0)
451 error (_("'%s': No such file\n"), file_name);
453 error (_("Could not locate '%s'. System error message: %s\n"),
454 file_name, strerror (errno));
458 if (! S_ISREG (statbuf_p->st_mode))
460 error (_("'%s' is not an ordinary file\n"), file_name);
468 process_file (const char *file_name)
474 if (check_file (file_name, NULL))
477 file = fopen (file_name, "r+b");
480 error (_("Input file '%s' is not readable\n"), file_name);
484 if (fread (armag, SARMAG, 1, file) != 1)
486 error (_("%s: Failed to read file's magic number\n"),
492 if (memcmp (armag, ARMAG, SARMAG) == 0)
493 ret = process_archive (file_name, file, FALSE);
494 else if (memcmp (armag, ARMAGT, SARMAG) == 0)
495 ret = process_archive (file_name, file, TRUE);
499 archive_file_size = archive_file_offset = 0;
500 ret = process_object (file_name, file);
515 { ELFOSABI_NONE, "none" },
516 { ELFOSABI_HPUX, "HPUX" },
517 { ELFOSABI_NETBSD, "NetBSD" },
518 { ELFOSABI_GNU, "GNU" },
519 { ELFOSABI_GNU, "Linux" },
520 { ELFOSABI_SOLARIS, "Solaris" },
521 { ELFOSABI_AIX, "AIX" },
522 { ELFOSABI_IRIX, "Irix" },
523 { ELFOSABI_FREEBSD, "FreeBSD" },
524 { ELFOSABI_TRU64, "TRU64" },
525 { ELFOSABI_MODESTO, "Modesto" },
526 { ELFOSABI_OPENBSD, "OpenBSD" },
527 { ELFOSABI_OPENVMS, "OpenVMS" },
528 { ELFOSABI_NSK, "NSK" },
529 { ELFOSABI_AROS, "AROS" },
530 { ELFOSABI_FENIXOS, "FenixOS" }
533 /* Return ELFOSABI_XXX for an OSABI string, OSABI. */
536 elf_osabi (const char *osabi)
540 for (i = 0; i < ARRAY_SIZE (osabis); i++)
541 if (strcasecmp (osabi, osabis[i].name) == 0)
542 return osabis[i].osabi;
544 error (_("Unknown OSABI: %s\n"), osabi);
549 /* Return EM_XXX for a machine string, MACH. */
552 elf_machine (const char *mach)
554 if (strcasecmp (mach, "l1om") == 0)
556 if (strcasecmp (mach, "k1om") == 0)
558 if (strcasecmp (mach, "x86_64") == 0)
560 if (strcasecmp (mach, "x86-64") == 0)
562 if (strcasecmp (mach, "none") == 0)
565 error (_("Unknown machine type: %s\n"), mach);
570 /* Return ELF class for a machine type, MACH. */
584 error (_("Unknown machine type: %d\n"), mach);
589 /* Return ET_XXX for a type string, TYPE. */
592 elf_type (const char *type)
594 if (strcasecmp (type, "rel") == 0)
596 if (strcasecmp (type, "exec") == 0)
598 if (strcasecmp (type, "dyn") == 0)
600 if (strcasecmp (type, "none") == 0)
603 error (_("Unknown type: %s\n"), type);
608 enum command_line_switch
610 OPTION_INPUT_MACH = 150,
618 static struct option options[] =
620 {"input-mach", required_argument, 0, OPTION_INPUT_MACH},
621 {"output-mach", required_argument, 0, OPTION_OUTPUT_MACH},
622 {"input-type", required_argument, 0, OPTION_INPUT_TYPE},
623 {"output-type", required_argument, 0, OPTION_OUTPUT_TYPE},
624 {"input-osabi", required_argument, 0, OPTION_INPUT_OSABI},
625 {"output-osabi", required_argument, 0, OPTION_OUTPUT_OSABI},
626 {"version", no_argument, 0, 'v'},
627 {"help", no_argument, 0, 'h'},
628 {0, no_argument, 0, 0}
632 usage (FILE *stream, int exit_status)
634 fprintf (stream, _("Usage: %s <option(s)> elffile(s)\n"),
636 fprintf (stream, _(" Update the ELF header of ELF files\n"));
637 fprintf (stream, _(" The options are:\n"));
638 fprintf (stream, _("\
639 --input-mach <machine> Set input machine type to <machine>\n\
640 --output-mach <machine> Set output machine type to <machine>\n\
641 --input-type <type> Set input file type to <type>\n\
642 --output-type <type> Set output file type to <type>\n\
643 --input-osabi <osabi> Set input OSABI to <osabi>\n\
644 --output-osabi <osabi> Set output OSABI to <osabi>\n\
645 -h --help Display this information\n\
646 -v --version Display the version number of %s\n\
649 if (REPORT_BUGS_TO[0] && exit_status == 0)
650 fprintf (stream, _("Report bugs to %s\n"), REPORT_BUGS_TO);
655 main (int argc, char ** argv)
659 #if defined (HAVE_SETLOCALE) && defined (HAVE_LC_MESSAGES)
660 setlocale (LC_MESSAGES, "");
662 #if defined (HAVE_SETLOCALE)
663 setlocale (LC_CTYPE, "");
665 bindtextdomain (PACKAGE, LOCALEDIR);
666 textdomain (PACKAGE);
668 expandargv (&argc, &argv);
670 while ((c = getopt_long (argc, argv, "hv",
671 options, (int *) 0)) != EOF)
675 case OPTION_INPUT_MACH:
676 input_elf_machine = elf_machine (optarg);
677 if (input_elf_machine < 0)
679 input_elf_class = elf_class (input_elf_machine);
680 if (input_elf_class < 0)
684 case OPTION_OUTPUT_MACH:
685 output_elf_machine = elf_machine (optarg);
686 if (output_elf_machine < 0)
690 case OPTION_INPUT_TYPE:
691 input_elf_type = elf_type (optarg);
692 if (input_elf_type < 0)
696 case OPTION_OUTPUT_TYPE:
697 output_elf_type = elf_type (optarg);
698 if (output_elf_type < 0)
702 case OPTION_INPUT_OSABI:
703 input_elf_osabi = elf_osabi (optarg);
704 if (input_elf_osabi < 0)
708 case OPTION_OUTPUT_OSABI:
709 output_elf_osabi = elf_osabi (optarg);
710 if (output_elf_osabi < 0)
718 print_version (program_name);
727 || (output_elf_machine == -1
728 && output_elf_type == -1
729 && output_elf_osabi == -1))
733 while (optind < argc)
734 status |= process_file (argv[optind++]);