/* Print information from ELF file in human-readable form.
Copyright (C) 2005, 2006, 2007, 2009, 2011, 2012, 2014, 2015 Red Hat, Inc.
This file is part of elfutils.
Written by Ulrich Drepper <drepper@redhat.com>, 2005.
This file is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
elfutils is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <argp.h>
#include <error.h>
#include <fcntl.h>
#include <inttypes.h>
#include <libintl.h>
#include <locale.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdio_ext.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/param.h>
#include <system.h>
#include "../libebl/libeblP.h"
/* Name and version of program. */
static void print_version (FILE *stream, struct argp_state *state);
ARGP_PROGRAM_VERSION_HOOK_DEF = print_version;
/* Bug report address. */
ARGP_PROGRAM_BUG_ADDRESS_DEF = PACKAGE_BUGREPORT;
/* Definitions of arguments for argp functions. */
static const struct argp_option options[] =
{
{ NULL, 0, NULL, 0, N_("Mode selection:"), 0 },
{ "reloc", 'r', NULL, 0, N_("Display relocation information."), 0 },
{ "full-contents", 's', NULL, 0,
N_("Display the full contents of all sections requested"), 0 },
{ "disassemble", 'd', NULL, 0,
N_("Display assembler code of executable sections"), 0 },
{ NULL, 0, NULL, 0, N_("Output content selection:"), 0 },
{ "section", 'j', "NAME", 0,
N_("Only display information for section NAME."), 0 },
{ NULL, 0, NULL, 0, NULL, 0 }
};
/* Short description of program. */
static const char doc[] = N_("\
Show information from FILEs (a.out by default).");
/* Strings for arguments in help texts. */
static const char args_doc[] = N_("[FILE...]");
/* Prototype for option handler. */
static error_t parse_opt (int key, char *arg, struct argp_state *state);
/* Parser children. */
static struct argp_child argp_children[] =
{
{ &color_argp, 0, N_("Output formatting"), 2 },
{ NULL, 0, NULL, 0}
};
/* Data structure to communicate with argp functions. */
static const struct argp argp =
{
options, parse_opt, args_doc, doc, argp_children, NULL, NULL
};
/* Print symbols in file named FNAME. */
static int process_file (const char *fname, bool more_than_one);
/* Handle content of archive. */
static int handle_ar (int fd, Elf *elf, const char *prefix, const char *fname,
const char *suffix);
/* Handle ELF file. */
static int handle_elf (Elf *elf, const char *prefix, const char *fname,
const char *suffix);
#define INTERNAL_ERROR(fname) \
error (EXIT_FAILURE, 0, gettext ("%s: INTERNAL ERROR %d (%s): %s"), \
fname, __LINE__, PACKAGE_VERSION, elf_errmsg (-1))
/* List of sections which should be used. */
static struct section_list
{
bool is_name;
union
{
const char *name;
uint32_t scnndx;
};
struct section_list *next;
} *section_list;
/* If true print archive index. */
static bool print_relocs;
/* If true print full contents of requested sections. */
static bool print_full_content;
/* If true print disassembled output.. */
static bool print_disasm;
int
main (int argc, char *argv[])
{
/* We use no threads here which can interfere with handling a stream. */
(void) __fsetlocking (stdin, FSETLOCKING_BYCALLER);
(void) __fsetlocking (stdout, FSETLOCKING_BYCALLER);
(void) __fsetlocking (stderr, FSETLOCKING_BYCALLER);
/* Set locale. */
(void) setlocale (LC_ALL, "");
/* Make sure the message catalog can be found. */
(void) bindtextdomain (PACKAGE_TARNAME, LOCALEDIR);
/* Initialize the message catalog. */
(void) textdomain (PACKAGE_TARNAME);
/* Parse and process arguments. */
int remaining;
(void) argp_parse (&argp, argc, argv, 0, &remaining, NULL);
/* Tell the library which version we are expecting. */
(void) elf_version (EV_CURRENT);
int result = 0;
if (remaining == argc)
/* The user didn't specify a name so we use a.out. */
result = process_file ("a.out", false);
else
{
/* Process all the remaining files. */
const bool more_than_one = remaining + 1 < argc;
do
result |= process_file (argv[remaining], more_than_one);
while (++remaining < argc);
}
return result;
}
/* Print the version information. */
static void
print_version (FILE *stream, struct argp_state *state __attribute__ ((unused)))
{
fprintf (stream, "objdump (%s) %s\n", PACKAGE_NAME, PACKAGE_VERSION);
fprintf (stream, gettext ("\
Copyright (C) %s Red Hat, Inc.\n\
This is free software; see the source for copying conditions. There is NO\n\
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n\
"), "2012");
fprintf (stream, gettext ("Written by %s.\n"), "Ulrich Drepper");
}
/* Handle program arguments. */
static error_t
parse_opt (int key, char *arg,
struct argp_state *state __attribute__ ((unused)))
{
/* True if any of the control options is set. */
static bool any_control_option;
switch (key)
{
case 'j':
{
struct section_list *newp = xmalloc (sizeof (*newp));
char *endp;
newp->scnndx = strtoul (arg, &endp, 0);
if (*endp == 0)
newp->is_name = false;
else
{
newp->name = arg;
newp->is_name = true;
}
newp->next = section_list;
section_list = newp;
}
any_control_option = true;
break;
case 'd':
print_disasm = true;
any_control_option = true;
break;
case 'r':
print_relocs = true;
any_control_option = true;
break;
case 's':
print_full_content = true;
any_control_option = true;
break;
case ARGP_KEY_FINI:
if (! any_control_option)
{
fputs (gettext ("No operation specified.\n"), stderr);
argp_help (&argp, stderr, ARGP_HELP_SEE,
program_invocation_short_name);
exit (EXIT_FAILURE);
}
default:
return ARGP_ERR_UNKNOWN;
}
return 0;
}
/* Open the file and determine the type. */
static int
process_file (const char *fname, bool more_than_one)
{
/* Open the file. */
int fd = open (fname, O_RDONLY);
if (fd == -1)
{
error (0, errno, gettext ("cannot open %s"), fname);
return 1;
}
/* Now get the ELF descriptor. */
Elf *elf = elf_begin (fd, ELF_C_READ_MMAP, NULL);
if (elf != NULL)
{
if (elf_kind (elf) == ELF_K_ELF)
{
int result = handle_elf (elf, more_than_one ? "" : NULL,
fname, NULL);
if (elf_end (elf) != 0)
INTERNAL_ERROR (fname);
if (close (fd) != 0)
error (EXIT_FAILURE, errno, gettext ("while close `%s'"), fname);
return result;
}
else if (elf_kind (elf) == ELF_K_AR)
{
int result = handle_ar (fd, elf, NULL, fname, NULL);
if (elf_end (elf) != 0)
INTERNAL_ERROR (fname);
if (close (fd) != 0)
error (EXIT_FAILURE, errno, gettext ("while close `%s'"), fname);
return result;
}
/* We cannot handle this type. Close the descriptor anyway. */
if (elf_end (elf) != 0)
INTERNAL_ERROR (fname);
}
error (0, 0, gettext ("%s: File format not recognized"), fname);
return 1;
}
static int
handle_ar (int fd, Elf *elf, const char *prefix, const char *fname,
const char *suffix)
{
size_t fname_len = strlen (fname) + 1;
size_t prefix_len = prefix != NULL ? strlen (prefix) : 0;
char new_prefix[prefix_len + fname_len + 2];
size_t suffix_len = suffix != NULL ? strlen (suffix) : 0;
char new_suffix[suffix_len + 2];
Elf *subelf;
Elf_Cmd cmd = ELF_C_READ_MMAP;
int result = 0;
char *cp = new_prefix;
if (prefix != NULL)
cp = stpcpy (cp, prefix);
cp = stpcpy (cp, fname);
stpcpy (cp, "[");
cp = new_suffix;
if (suffix != NULL)
cp = stpcpy (cp, suffix);
stpcpy (cp, "]");
/* Process all the files contained in the archive. */
while ((subelf = elf_begin (fd, cmd, elf)) != NULL)
{
/* The the header for this element. */
Elf_Arhdr *arhdr = elf_getarhdr (subelf);
/* Skip over the index entries. */
if (strcmp (arhdr->ar_name, "/") != 0
&& strcmp (arhdr->ar_name, "//") != 0)
{
if (elf_kind (subelf) == ELF_K_ELF)
result |= handle_elf (subelf, new_prefix, arhdr->ar_name,
new_suffix);
else if (elf_kind (subelf) == ELF_K_AR)
result |= handle_ar (fd, subelf, new_prefix, arhdr->ar_name,
new_suffix);
else
{
error (0, 0, gettext ("%s%s%s: file format not recognized"),
new_prefix, arhdr->ar_name, new_suffix);
result = 1;
}
}
/* Get next archive element. */
cmd = elf_next (subelf);
if (elf_end (subelf) != 0)
INTERNAL_ERROR (fname);
}
return result;
}
static void
show_relocs_x (Ebl *ebl, GElf_Shdr *shdr, Elf_Data *symdata,
Elf_Data *xndxdata, size_t symstrndx, size_t shstrndx,
GElf_Addr r_offset, GElf_Xword r_info, GElf_Sxword r_addend)
{
int elfclass = gelf_getclass (ebl->elf);
char buf[128];
printf ("%0*" PRIx64 " %-20s ",
elfclass == ELFCLASS32 ? 8 : 16, r_offset,
ebl_reloc_type_name (ebl, GELF_R_TYPE (r_info), buf, sizeof (buf)));
Elf32_Word xndx;
GElf_Sym symmem;
GElf_Sym *sym = gelf_getsymshndx (symdata, xndxdata, GELF_R_SYM (r_info),
&symmem, &xndx);
if (sym == NULL)
printf ("<%s %ld>",
gettext ("INVALID SYMBOL"), (long int) GELF_R_SYM (r_info));
else if (GELF_ST_TYPE (sym->st_info) != STT_SECTION)
printf ("%s",
elf_strptr (ebl->elf, symstrndx, sym->st_name));
else
{
GElf_Shdr destshdr_mem;
GElf_Shdr *destshdr;
destshdr = gelf_getshdr (elf_getscn (ebl->elf,
sym->st_shndx == SHN_XINDEX
? xndx : sym->st_shndx),
&destshdr_mem);
if (shdr == NULL || destshdr == NULL)
printf ("<%s %ld>",
gettext ("INVALID SECTION"),
(long int) (sym->st_shndx == SHN_XINDEX
? xndx : sym->st_shndx));
else
printf ("%s",
elf_strptr (ebl->elf, shstrndx, destshdr->sh_name));
}
if (r_addend != 0)
{
char sign = '+';
if (r_addend < 0)
{
sign = '-';
r_addend = -r_addend;
}
printf ("%c%#" PRIx64, sign, r_addend);
}
putchar ('\n');
}
static void
show_relocs_rel (Ebl *ebl, GElf_Shdr *shdr, Elf_Data *data,
Elf_Data *symdata, Elf_Data *xndxdata, size_t symstrndx,
size_t shstrndx)
{
size_t sh_entsize = gelf_fsize (ebl->elf, ELF_T_REL, 1, EV_CURRENT);
int nentries = shdr->sh_size / sh_entsize;
for (int cnt = 0; cnt < nentries; ++cnt)
{
GElf_Rel relmem;
GElf_Rel *rel;
rel = gelf_getrel (data, cnt, &relmem);
if (rel != NULL)
show_relocs_x (ebl, shdr, symdata, xndxdata, symstrndx, shstrndx,
rel->r_offset, rel->r_info, 0);
}
}
static void
show_relocs_rela (Ebl *ebl, GElf_Shdr *shdr, Elf_Data *data,
Elf_Data *symdata, Elf_Data *xndxdata, size_t symstrndx,
size_t shstrndx)
{
size_t sh_entsize = gelf_fsize (ebl->elf, ELF_T_RELA, 1, EV_CURRENT);
int nentries = shdr->sh_size / sh_entsize;
for (int cnt = 0; cnt < nentries; ++cnt)
{
GElf_Rela relmem;
GElf_Rela *rel;
rel = gelf_getrela (data, cnt, &relmem);
if (rel != NULL)
show_relocs_x (ebl, shdr, symdata, xndxdata, symstrndx, shstrndx,
rel->r_offset, rel->r_info, rel->r_addend);
}
}
static bool
section_match (Elf *elf, uint32_t scnndx, GElf_Shdr *shdr, size_t shstrndx)
{
if (section_list == NULL)
return true;
struct section_list *runp = section_list;
const char *name = elf_strptr (elf, shstrndx, shdr->sh_name);
do
{
if (runp->is_name)
{
if (name && strcmp (runp->name, name) == 0)
return true;
}
else
{
if (runp->scnndx == scnndx)
return true;
}
runp = runp->next;
}
while (runp != NULL);
return false;
}
static int
show_relocs (Ebl *ebl, const char *fname, uint32_t shstrndx)
{
int elfclass = gelf_getclass (ebl->elf);
Elf_Scn *scn = NULL;
while ((scn = elf_nextscn (ebl->elf, scn)) != NULL)
{
GElf_Shdr shdr_mem;
GElf_Shdr *shdr = gelf_getshdr (scn, &shdr_mem);
if (shdr == NULL)
INTERNAL_ERROR (fname);
if (shdr->sh_type == SHT_REL || shdr->sh_type == SHT_RELA)
{
if (! section_match (ebl->elf, elf_ndxscn (scn), shdr, shstrndx))
continue;
GElf_Shdr destshdr_mem;
GElf_Shdr *destshdr = gelf_getshdr (elf_getscn (ebl->elf,
shdr->sh_info),
&destshdr_mem);
if (unlikely (destshdr == NULL))
continue;
printf (gettext ("\nRELOCATION RECORDS FOR [%s]:\n"
"%-*s TYPE VALUE\n"),
elf_strptr (ebl->elf, shstrndx, destshdr->sh_name),
elfclass == ELFCLASS32 ? 8 : 16, gettext ("OFFSET"));
/* Get the data of the section. */
Elf_Data *data = elf_getdata (scn, NULL);
if (data == NULL)
continue;
/* Get the symbol table information. */
Elf_Scn *symscn = elf_getscn (ebl->elf, shdr->sh_link);
GElf_Shdr symshdr_mem;
GElf_Shdr *symshdr = gelf_getshdr (symscn, &symshdr_mem);
Elf_Data *symdata = elf_getdata (symscn, NULL);
if (unlikely (symshdr == NULL || symdata == NULL))
continue;
/* Search for the optional extended section index table. */
Elf_Data *xndxdata = NULL;
Elf_Scn *xndxscn = NULL;
while ((xndxscn = elf_nextscn (ebl->elf, xndxscn)) != NULL)
{
GElf_Shdr xndxshdr_mem;
GElf_Shdr *xndxshdr;
xndxshdr = gelf_getshdr (xndxscn, &xndxshdr_mem);
if (xndxshdr != NULL && xndxshdr->sh_type == SHT_SYMTAB_SHNDX
&& xndxshdr->sh_link == elf_ndxscn (symscn))
{
/* Found it. */
xndxdata = elf_getdata (xndxscn, NULL);
break;
}
}
if (shdr->sh_type == SHT_REL)
show_relocs_rel (ebl, shdr, data, symdata, xndxdata,
symshdr->sh_link, shstrndx);
else
show_relocs_rela (ebl, shdr, data, symdata, xndxdata,
symshdr->sh_link, shstrndx);
putchar ('\n');
}
}
return 0;
}
static int
show_full_content (Ebl *ebl, const char *fname, uint32_t shstrndx)
{
Elf_Scn *scn = NULL;
while ((scn = elf_nextscn (ebl->elf, scn)) != NULL)
{
GElf_Shdr shdr_mem;
GElf_Shdr *shdr = gelf_getshdr (scn, &shdr_mem);
if (shdr == NULL)
INTERNAL_ERROR (fname);
if (shdr->sh_type == SHT_PROGBITS && shdr->sh_size > 0)
{
if (! section_match (ebl->elf, elf_ndxscn (scn), shdr, shstrndx))
continue;
printf (gettext ("Contents of section %s:\n"),
elf_strptr (ebl->elf, shstrndx, shdr->sh_name));
/* Get the data of the section. */
Elf_Data *data = elf_getdata (scn, NULL);
if (data == NULL)
continue;
unsigned char *cp = data->d_buf;
size_t cnt;
for (cnt = 0; cnt + 16 < data->d_size; cp += 16, cnt += 16)
{
printf (" %04zx ", cnt);
for (size_t inner = 0; inner < 16; inner += 4)
printf ("%02hhx%02hhx%02hhx%02hhx ",
cp[inner], cp[inner + 1], cp[inner + 2],
cp[inner + 3]);
fputc_unlocked (' ', stdout);
for (size_t inner = 0; inner < 16; ++inner)
fputc_unlocked (isascii (cp[inner]) && isprint (cp[inner])
? cp[inner] : '.', stdout);
fputc_unlocked ('\n', stdout);
}
printf (" %04zx ", cnt);
size_t remaining = data->d_size - cnt;
size_t inner;
for (inner = 0; inner + 4 <= remaining; inner += 4)
printf ("%02hhx%02hhx%02hhx%02hhx ",
cp[inner], cp[inner + 1], cp[inner + 2], cp[inner + 3]);
for (; inner < remaining; ++inner)
printf ("%02hhx", cp[inner]);
for (inner = 2 * (16 - inner) + (16 - inner + 3) / 4 + 1; inner > 0;
--inner)
fputc_unlocked (' ', stdout);
for (inner = 0; inner < remaining; ++inner)
fputc_unlocked (isascii (cp[inner]) && isprint (cp[inner])
? cp[inner] : '.', stdout);
fputc_unlocked ('\n', stdout);
fputc_unlocked ('\n', stdout);
}
}
return 0;
}
struct disasm_info
{
GElf_Addr addr;
const uint8_t *cur;
const uint8_t *last_end;
const char *address_color;
const char *bytes_color;
};
// XXX This is not the preferred output for all architectures. Needs
// XXX customization, too.
static int
disasm_output (char *buf, size_t buflen, void *arg)
{
struct disasm_info *info = (struct disasm_info *) arg;
if (info->address_color != NULL)
printf ("%s%8" PRIx64 "%s: ",
info->address_color, (uint64_t) info->addr, color_off);
else
printf ("%8" PRIx64 ": ", (uint64_t) info->addr);
if (info->bytes_color != NULL)
fputs_unlocked (info->bytes_color, stdout);
size_t cnt;
for (cnt = 0; cnt < (size_t) MIN (info->cur - info->last_end, 8); ++cnt)
printf (" %02" PRIx8, info->last_end[cnt]);
if (info->bytes_color != NULL)
fputs_unlocked (color_off, stdout);
printf ("%*s %.*s\n",
(int) (8 - cnt) * 3 + 1, "", (int) buflen, buf);
info->addr += cnt;
/* We limit the number of bytes printed before the mnemonic to 8.
Print the rest on a separate, following line. */
if (info->cur - info->last_end > 8)
{
if (info->address_color != NULL)
printf ("%s%8" PRIx64 "%s: ",
info->address_color, (uint64_t) info->addr, color_off);
else
printf ("%8" PRIx64 ": ", (uint64_t) info->addr);
if (info->bytes_color != NULL)
fputs_unlocked (info->bytes_color, stdout);
for (; cnt < (size_t) (info->cur - info->last_end); ++cnt)
printf (" %02" PRIx8, info->last_end[cnt]);
if (info->bytes_color != NULL)
fputs_unlocked (color_off, stdout);
putchar_unlocked ('\n');
info->addr += info->cur - info->last_end - 8;
}
info->last_end = info->cur;
return 0;
}
static int
show_disasm (Ebl *ebl, const char *fname, uint32_t shstrndx)
{
DisasmCtx_t *ctx = disasm_begin (ebl, ebl->elf, NULL /* XXX TODO */);
if (ctx == NULL)
error (EXIT_FAILURE, 0, gettext ("cannot disassemble"));
Elf_Scn *scn = NULL;
while ((scn = elf_nextscn (ebl->elf, scn)) != NULL)
{
GElf_Shdr shdr_mem;
GElf_Shdr *shdr = gelf_getshdr (scn, &shdr_mem);
if (shdr == NULL)
INTERNAL_ERROR (fname);
if (shdr->sh_type == SHT_PROGBITS && shdr->sh_size > 0
&& (shdr->sh_flags & SHF_EXECINSTR) != 0)
{
if (! section_match (ebl->elf, elf_ndxscn (scn), shdr, shstrndx))
continue;
Elf_Data *data = elf_getdata (scn, NULL);
if (data == NULL)
continue;
printf ("Disassembly of section %s:\n\n",
elf_strptr (ebl->elf, shstrndx, shdr->sh_name));
struct disasm_info info;
info.addr = shdr->sh_addr;
info.last_end = info.cur = data->d_buf;
char *fmt;
if (color_mode)
{
info.address_color = color_address;
info.bytes_color = color_bytes;
if (asprintf (&fmt, "%s%%7m %s%%.1o,%s%%.2o,%s%%.3o%%34a %s%%l",
color_mnemonic ?: "",
color_operand1 ?: "",
color_operand2 ?: "",
color_operand3 ?: "",
color_label ?: "") < 0)
error (EXIT_FAILURE, errno, _("cannot allocate memory"));
}
else
{
info.address_color = info.bytes_color = NULL;
fmt = "%7m %.1o,%.2o,%.3o%34a %l";
}
disasm_cb (ctx, &info.cur, info.cur + data->d_size, info.addr,
fmt, disasm_output, &info, NULL /* XXX */);
if (color_mode)
free (fmt);
}
}
(void) disasm_end (ctx);
return 0;
}
static int
handle_elf (Elf *elf, const char *prefix, const char *fname,
const char *suffix)
{
/* Get the backend for this object file type. */
Ebl *ebl = ebl_openbackend (elf);
printf ("%s: elf%d-%s\n\n",
fname, gelf_getclass (elf) == ELFCLASS32 ? 32 : 64,
ebl_backend_name (ebl));
/* Create the full name of the file. */
size_t prefix_len = prefix == NULL ? 0 : strlen (prefix);
size_t suffix_len = suffix == NULL ? 0 : strlen (suffix);
size_t fname_len = strlen (fname) + 1;
char fullname[prefix_len + 1 + fname_len + suffix_len];
char *cp = fullname;
if (prefix != NULL)
cp = mempcpy (cp, prefix, prefix_len);
cp = mempcpy (cp, fname, fname_len);
if (suffix != NULL)
memcpy (cp - 1, suffix, suffix_len + 1);
/* Get the section header string table index. */
size_t shstrndx;
if (elf_getshdrstrndx (ebl->elf, &shstrndx) < 0)
error (EXIT_FAILURE, 0,
gettext ("cannot get section header string table index"));
int result = 0;
if (print_disasm)
result = show_disasm (ebl, fullname, shstrndx);
if (print_relocs && !print_disasm)
result = show_relocs (ebl, fullname, shstrndx);
if (print_full_content)
result = show_full_content (ebl, fullname, shstrndx);
/* Close the ELF backend library descriptor. */
ebl_closebackend (ebl);
return result;
}
#include "debugpred.h"