bfd/seclet.h


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/* Definitions of little sections (seclets) for BFD.
   Copyright 1992 Free Software Foundation, Inc.
   Hacked by Steve Chamberlain of Cygnus Support.

This file is part of BFD, the Binary File Descriptor library.

This program 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 2 of the License, or
(at your option) any later version.

This program 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, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */

#ifndef _SECLET_H
#define _SECLET_H

typedef enum bfd_seclet_enum
{
  bfd_indirect_seclet,
  bfd_fill_seclet
} bfd_seclet_enum_type;


struct bfd_seclet_struct 
{
  struct bfd_seclet_struct *next;
  bfd_seclet_enum_type type;
  unsigned int offset;  
  unsigned int size;
  union 
  {
    struct 
    {
      asection *section;
      asymbol **symbols;
    } indirect;
    struct {
      int value;
    } fill;
  }
  u;
};

typedef struct bfd_seclet_struct bfd_seclet_type;

bfd_seclet_type *
bfd_new_seclet PARAMS ((bfd*, asection*));

#endif
/* Plugin support for BFD.
   Copyright (C) 2009-2019 Free Software Foundation, Inc.

   This file is part of BFD, the Binary File Descriptor library.

   This program 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.

   This program 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, write to the Free Software
   Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
   MA 02110-1301, USA.  */

#include "sysdep.h"
#include "bfd.h"

#if BFD_SUPPORTS_PLUGINS

#include <assert.h>
#ifdef HAVE_DLFCN_H
#include <dlfcn.h>
#elif defined (HAVE_WINDOWS_H)
#include <windows.h>
#else
#error Unknown how to handle dynamic-load-libraries.
#endif
#include <stdarg.h>
#include "plugin-api.h"
#include "plugin.h"
#include "libbfd.h"
#include "libiberty.h"
#include <dirent.h>

#if !defined (HAVE_DLFCN_H) && defined (HAVE_WINDOWS_H)

#define RTLD_NOW 0      /* Dummy value.  */

static void *
dlopen (const char *file, int mode ATTRIBUTE_UNUSED)
{
  return LoadLibrary (file);
}

static void *
dlsym (void *handle, const char *name)
{
  return GetProcAddress (handle, name);
}

static int ATTRIBUTE_UNUSED
dlclose (void *handle)
{
  FreeLibrary (handle);
  return 0;
}

static const char *
dlerror (void)
{
  return "Unable to load DLL.";
}

#endif /* !defined (HAVE_DLFCN_H) && defined (HAVE_WINDOWS_H)  */

#define bfd_plugin_close_and_cleanup		      _bfd_generic_close_and_cleanup
#define bfd_plugin_bfd_free_cached_info		      _bfd_generic_bfd_free_cached_info
#define bfd_plugin_new_section_hook		      _bfd_generic_new_section_hook
#define bfd_plugin_get_section_contents		      _bfd_generic_get_section_contents
#define bfd_plugin_get_section_contents_in_window     _bfd_generic_get_section_contents_in_window
#define bfd_plugin_bfd_copy_private_header_data	      _bfd_generic_bfd_copy_private_header_data
#define bfd_plugin_bfd_merge_private_bfd_data	      _bfd_generic_bfd_merge_private_bfd_data
#define bfd_plugin_bfd_copy_private_header_data	      _bfd_generic_bfd_copy_private_header_data
#define bfd_plugin_bfd_set_private_flags	      _bfd_generic_bfd_set_private_flags
#define bfd_plugin_core_file_matches_executable_p     generic_core_file_matches_executable_p
#define bfd_plugin_bfd_is_local_label_name	      _bfd_nosymbols_bfd_is_local_label_name
#define bfd_plugin_bfd_is_target_special_symbol	      _bfd_bool_bfd_asymbol_false
#define bfd_plugin_get_lineno			      _bfd_nosymbols_get_lineno
#define bfd_plugin_find_nearest_line		      _bfd_nosymbols_find_nearest_line
#define bfd_plugin_find_line			      _bfd_nosymbols_find_line
#define bfd_plugin_find_inliner_info		      _bfd_nosymbols_find_inliner_info
#define bfd_plugin_get_symbol_version_string	      _bfd_nosymbols_get_symbol_version_string
#define bfd_plugin_bfd_make_debug_symbol	      _bfd_nosymbols_bfd_make_debug_symbol
#define bfd_plugin_read_minisymbols		      _bfd_generic_read_minisymbols
#define bfd_plugin_minisymbol_to_symbol		      _bfd_generic_minisymbol_to_symbol
#define bfd_plugin_set_arch_mach		      bfd_default_set_arch_mach
#define bfd_plugin_set_section_contents		      _bfd_generic_set_section_contents
#define bfd_plugin_bfd_get_relocated_section_contents bfd_generic_get_relocated_section_contents
#define bfd_plugin_bfd_relax_section		      bfd_generic_relax_section
#define bfd_plugin_bfd_link_hash_table_create	      _bfd_generic_link_hash_table_create
#define bfd_plugin_bfd_link_add_symbols		      _bfd_generic_link_add_symbols
#define bfd_plugin_bfd_link_just_syms		      _bfd_generic_link_just_syms
#define bfd_plugin_bfd_final_link		      _bfd_generic_final_link
#define bfd_plugin_bfd_link_split_section	      _bfd_generic_link_split_section
#define bfd_plugin_bfd_gc_sections		      bfd_generic_gc_sections
#define bfd_plugin_bfd_lookup_section_flags	      bfd_generic_lookup_section_flags
#define bfd_plugin_bfd_merge_sections		      bfd_generic_merge_sections
#define bfd_plugin_bfd_is_group_section		      bfd_generic_is_group_section
#define bfd_plugin_bfd_group_name		      bfd_generic_group_name
#define bfd_plugin_bfd_discard_group		      bfd_generic_discard_group
#define bfd_plugin_section_already_linked	      _bfd_generic_section_already_linked
#define bfd_plugin_bfd_define_common_symbol	      bfd_generic_define_common_symbol
#define bfd_plugin_bfd_link_hide_symbol		      _bfd_generic_link_hide_symbol
#define bfd_plugin_bfd_define_start_stop	      bfd_generic_define_start_stop
#define bfd_plugin_bfd_copy_link_hash_symbol_type     _bfd_generic_copy_link_hash_symbol_type
#define bfd_plugin_bfd_link_check_relocs	      _bfd_generic_link_check_relocs

static enum ld_plugin_status
message (int level ATTRIBUTE_UNUSED,
	 const char * format, ...)
{
  va_list args;
  va_start (args, format);
  printf ("bfd plugin: ");
  vprintf (format, args);
  putchar ('\n');
  va_end (args);
  return LDPS_OK;
}

/* Register a claim-file handler. */
static ld_plugin_claim_file_handler claim_file = NULL;

static enum ld_plugin_status
register_claim_file (ld_plugin_claim_file_handler handler)
{
  claim_file = handler;
  return LDPS_OK;
}

static enum ld_plugin_status
add_symbols (void * handle,
	     int nsyms,
	     const struct ld_plugin_symbol * syms)
{
  bfd *abfd = handle;
  struct plugin_data_struct *plugin_data =
    bfd_alloc (abfd, sizeof (plugin_data_struct));

  plugin_data->nsyms = nsyms;
  plugin_data->syms = syms;

  if (nsyms != 0)
    abfd->flags |= HAS_SYMS;

  abfd->tdata.plugin_data = plugin_data;
  return LDPS_OK;
}

static const char *plugin_program_name;

void
bfd_plugin_set_program_name (const char *program_name)
{
  plugin_program_name = program_name;
}

int
bfd_plugin_open_input (bfd *ibfd, struct ld_plugin_input_file *file)
{
  bfd *iobfd;

  iobfd = ibfd;
  while (iobfd->my_archive
	 && !bfd_is_thin_archive (iobfd->my_archive))
    iobfd = iobfd->my_archive;
  file->name = iobfd->filename;

  if (!iobfd->iostream && !bfd_open_file (iobfd))
    return 0;

  /* The plugin API expects that the file descriptor won't be closed
     and reused as done by the bfd file cache.  So open it again.
     dup isn't good enough.  plugin IO uses lseek/read while BFD uses
     fseek/fread.  It isn't wise to mix the unistd and stdio calls on
     the same underlying file descriptor.  */
  file->fd = open (file->name, O_RDONLY | O_BINARY);
  if (file->fd < 0)
    return 0;

  if (iobfd == ibfd)
    {
      struct stat stat_buf;

      if (fstat (file->fd, &stat_buf))
	{
	  close(file->fd);
	  return 0;
	}

      file->offset = 0;
      file->filesize = stat_buf.st_size;
    }
  else
    {
      file->offset = ibfd->origin;
      file->filesize = arelt_size (ibfd);
    }
  return 1;
}

static int
try_claim (bfd *abfd)
{
  int claimed = 0;
  struct ld_plugin_input_file file;

  file.handle = abfd;
  if (!bfd_plugin_open_input (abfd, &file))
    return 0;
  if (claim_file)
    claim_file (&file, &claimed);
  close (file.fd);
  return claimed;
}

struct plugin_list_entry
{
  void *                        handle;
  ld_plugin_claim_file_handler  claim_file;
  struct plugin_list_entry *    next;
};

static struct plugin_list_entry * plugin_list = NULL;

static int
try_load_plugin (const char *pname, bfd *abfd, int *has_plugin_p)
{
  void *plugin_handle = NULL;
  struct ld_plugin_tv tv[4];
  int i;
  ld_plugin_onload onload;
  enum ld_plugin_status status;
  struct plugin_list_entry *plugin_list_iter;

  *has_plugin_p = 0;

  plugin_handle = dlopen (pname, RTLD_NOW);
  if (!plugin_handle)
    {
      _bfd_error_handler ("%s\n", dlerror ());
      return 0;
    }

  for (plugin_list_iter = plugin_list;
       plugin_list_iter;
       plugin_list_iter = plugin_list_iter->next)
    {
      if (plugin_handle == plugin_list_iter->handle)
	{
	  dlclose (plugin_handle);
	  if (!plugin_list_iter->claim_file)
	    return 0;

	  register_claim_file (plugin_list_iter->claim_file);
	  goto have_claim_file;
	}
    }

  plugin_list_iter = bfd_malloc (sizeof *plugin_list_iter);
  if (plugin_list_iter == NULL)
    return 0;
  plugin_list_iter->handle = plugin_handle;
  plugin_list_iter->claim_file = NULL;
  plugin_list_iter->next = plugin_list;
  plugin_list = plugin_list_iter;

  onload = dlsym (plugin_handle, "onload");
  if (!onload)
    return 0;

  i = 0;
  tv[i].tv_tag = LDPT_MESSAGE;
  tv[i].tv_u.tv_message = message;

  ++i;
  tv[i].tv_tag = LDPT_REGISTER_CLAIM_FILE_HOOK;
  tv[i].tv_u.tv_register_claim_file = register_claim_file;

  ++i;
  tv[i].tv_tag = LDPT_ADD_SYMBOLS;
  tv[i].tv_u.tv_add_symbols = add_symbols;

  ++i;
  tv[i].tv_tag = LDPT_NULL;
  tv[i].tv_u.tv_val = 0;

  status = (*onload)(tv);

  if (status != LDPS_OK)
    return 0;

  plugin_list_iter->claim_file = claim_file;

have_claim_file:
  *has_plugin_p = 1;

  abfd->plugin_format = bfd_plugin_no;

  if (!claim_file)
    return 0;

  if (!try_claim (abfd))
    return 0;

  abfd->plugin_format = bfd_plugin_yes;
  return 1;
}

/* There may be plugin libraries in lib/bfd-plugins.  */

static int has_plugin = -1;

static const bfd_target *(*ld_plugin_object_p) (bfd *);

static const char *plugin_name;

void