bfd/mach-o-i386.c

   1 /* Intel i386 Mach-O support for BFD.
   2    Copyright (C) 2009-2019 Free Software Foundation, Inc.
   3
   4    This file is part of BFD, the Binary File Descriptor library.
   5
   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.
  10
  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.
  15
  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,
  19    MA 02110-1301, USA.  */
  20
  21 #include "sysdep.h"
  22 #include "bfd.h"
  23 #include "libbfd.h"
  24 #include "libiberty.h"
  25 #include "mach-o.h"
  26 #include "mach-o/reloc.h"
  27
  28 #define bfd_mach_o_object_p bfd_mach_o_i386_object_p
  29 #define bfd_mach_o_core_p bfd_mach_o_i386_core_p
  30 #define bfd_mach_o_mkobject bfd_mach_o_i386_mkobject
  31
  32 static const bfd_target *
  33 bfd_mach_o_i386_object_p (bfd *abfd)
  34 {
  35   return bfd_mach_o_header_p (abfd, 0, 0, BFD_MACH_O_CPU_TYPE_I386);
  36 }
  37
  38 static const bfd_target *
  39 bfd_mach_o_i386_core_p (bfd *abfd)
  40 {
  41   return bfd_mach_o_header_p (abfd, 0,
  42                               BFD_MACH_O_MH_CORE, BFD_MACH_O_CPU_TYPE_I386);
  43 }
  44
  45 static bfd_boolean
  46 bfd_mach_o_i386_mkobject (bfd *abfd)
  47 {
  48   bfd_mach_o_data_struct *mdata;
  49
  50   if (!bfd_mach_o_mkobject_init (abfd))
  51     return FALSE;
  52
  53   mdata = bfd_mach_o_get_data (abfd);
  54   mdata->header.magic = BFD_MACH_O_MH_MAGIC;
  55   mdata->header.cputype = BFD_MACH_O_CPU_TYPE_I386;
  56   mdata->header.cpusubtype = BFD_MACH_O_CPU_SUBTYPE_X86_ALL;
  57   mdata->header.byteorder = BFD_ENDIAN_LITTLE;
  58   mdata->header.version = 1;
  59
  60   return TRUE;
  61 }
  62
  63 static reloc_howto_type i386_howto_table[]=
  64 {
  65   /* 0 */
  66   HOWTO(BFD_RELOC_32, 0, 2, 32, FALSE, 0,
  67         complain_overflow_bitfield,
  68         NULL, "32",
  69         FALSE, 0xffffffff, 0xffffffff, FALSE),
  70   HOWTO(BFD_RELOC_16, 0, 1, 16, FALSE, 0,
  71         complain_overflow_bitfield,
  72         NULL, "16",
  73         FALSE, 0xffff, 0xffff, FALSE),
  74   HOWTO(BFD_RELOC_8, 0, 0, 8, FALSE, 0,
  75         complain_overflow_bitfield,
  76         NULL, "8",
  77         FALSE, 0xff, 0xff, FALSE),
  78   HOWTO(BFD_RELOC_32_PCREL, 0, 2, 32, TRUE, 0,
  79         complain_overflow_bitfield,
  80         NULL, "DISP32",
  81         FALSE, 0xffffffff, 0xffffffff, TRUE),
  82   /* 4 */
  83   HOWTO(BFD_RELOC_16_PCREL, 0, 1, 16, TRUE, 0,
  84         complain_overflow_bitfield,
  85         NULL, "DISP16",
  86         FALSE, 0xffff, 0xffff, TRUE),
  87   HOWTO(BFD_RELOC_MACH_O_SECTDIFF, 0, 2, 32, FALSE, 0,
  88         complain_overflow_bitfield,
  89         NULL, "SECTDIFF_32",
  90         FALSE, 0xffffffff, 0xffffffff, FALSE),
  91   HOWTO(BFD_RELOC_MACH_O_LOCAL_SECTDIFF, 0, 2, 32, FALSE, 0,
  92         complain_overflow_bitfield,
  93         NULL, "LSECTDIFF_32",
  94         FALSE, 0xffffffff, 0xffffffff, FALSE),
  95   HOWTO(BFD_RELOC_MACH_O_PAIR, 0, 2, 32, FALSE, 0,
  96         complain_overflow_bitfield,
  97         NULL, "PAIR_32",
  98         FALSE, 0xffffffff, 0xffffffff, FALSE),
  99   /* 8 */
 100   HOWTO(BFD_RELOC_MACH_O_SECTDIFF, 0, 1, 16, FALSE, 0,
 101         complain_overflow_bitfield,
 102         NULL, "SECTDIFF_16",
 103         FALSE, 0xffff, 0xffff, FALSE),
 104   HOWTO(BFD_RELOC_MACH_O_LOCAL_SECTDIFF, 0, 1, 16, FALSE, 0,
 105         complain_overflow_bitfield,
 106         NULL, "LSECTDIFF_16",
 107         FALSE, 0xffff, 0xffff, FALSE),
 108   HOWTO(BFD_RELOC_MACH_O_PAIR, 0, 1, 16, FALSE, 0,
 109         complain_overflow_bitfield,
 110         NULL, "PAIR_16",
 111         FALSE, 0xffff, 0xffff, FALSE),
 112 };
 113
 114 static bfd_boolean
 115 bfd_mach_o_i386_canonicalize_one_reloc (bfd *       abfd,
 116                                         struct mach_o_reloc_info_external * raw,
 117                                         arelent *   res,
 118                                         asymbol **  syms,
 119                                         arelent *   res_base)
 120 {
 121   bfd_mach_o_reloc_info reloc;
 122
 123   if (!bfd_mach_o_pre_canonicalize_one_reloc (abfd, raw, &reloc, res, syms))
 124     return FALSE;
 125
 126   if (reloc.r_scattered)
 127     {
 128       switch (reloc.r_type)
 129         {
 130         case BFD_MACH_O_GENERIC_RELOC_PAIR:
 131           /* PR 21813: Check for a corrupt PAIR reloc at the start.  */
 132           if (res == res_base)
 133             return FALSE;
 134           if (reloc.r_length == 2)
 135             {
 136               res->howto = &i386_howto_table[7];
 137               res->address = res[-1].address;
 138               return TRUE;
 139             }
 140           else if (reloc.r_length == 1)
 141             {
 142               res->howto = &i386_howto_table[10];
 143               res->address = res[-1].address;
 144               return TRUE;
 145             }
 146           return FALSE;
 147         case BFD_MACH_O_GENERIC_RELOC_SECTDIFF:
 148           if (reloc.r_length == 2)
 149             {
 150               res->howto = &i386_howto_table[5];
 151               return TRUE;
 152             }
 153           else if (reloc.r_length == 1)
 154             {
 155               res->howto = &i386_howto_table[8];
 156               return TRUE;
 157             }
 158           return FALSE;
 159         case BFD_MACH_O_GENERIC_RELOC_LOCAL_SECTDIFF:
 160           if (reloc.r_length == 2)
 161             {
 162               res->howto = &i386_howto_table[6];
 163               return TRUE;
 164             }
 165           else if (reloc.r_length == 1)
 166             {
 167               res->howto = &i386_howto_table[9];
 168               return TRUE;
 169             }
 170           return FALSE;
 171         default:
 172           break;
 173         }
 174     }
 175   else
 176     {
 177       switch (reloc.r_type)
 178         {
 179         case BFD_MACH_O_GENERIC_RELOC_VANILLA:
 180           switch ((reloc.r_length << 1) | reloc.r_pcrel)
 181             {
 182             case 0: /* len = 0, pcrel = 0  */
 183               res->howto = &i386_howto_table[2];
 184               return TRUE;
 185             case 2: /* len = 1, pcrel = 0  */
 186               res->howto = &i386_howto_table[1];
 187               return TRUE;
 188             case 3: /* len = 1, pcrel = 1  */
 189               res->howto = &i386_howto_table[4];
 190               return TRUE;
 191             case 4: /* len = 2, pcrel = 0  */
 192               res->howto = &i386_howto_table[0];
 193               return TRUE;
 194             case 5: /* len = 2, pcrel = 1  */
 195               res->howto = &i386_howto_table[3];
 196               return TRUE;
 197             default:
 198               return FALSE;
 199             }
 200         default:
 201           break;
 202         }
 203     }
 204   return FALSE;
 205 }
 206
 207 static bfd_boolean
 208 bfd_mach_o_i386_swap_reloc_out (arelent *rel, bfd_mach_o_reloc_info *rinfo)
 209 {
 210   rinfo->r_address = rel->address;
 211   switch (rel->howto->type)
 212     {
 213     case BFD_RELOC_32:
 214     case BFD_RELOC_32_PCREL:
 215     case BFD_RELOC_16:
 216     case BFD_RELOC_16_PCREL:
 217     case BFD_RELOC_8:
 218       rinfo->r_scattered = 0;
 219       rinfo->r_type = BFD_MACH_O_GENERIC_RELOC_VANILLA;
 220       rinfo->r_pcrel = rel->howto->pc_relative;
 221       rinfo->r_length = rel->howto->size; /* Correct in practice.  */
 222       if ((*rel->sym_ptr_ptr)->flags & BSF_SECTION_SYM)
 223         {
 224           rinfo->r_extern = 0;
 225           rinfo->r_value =
 226             (*rel->sym_ptr_ptr)->section->output_section->target_index;
 227         }
 228       else
 229         {
 230           rinfo->r_extern = 1;
 231           rinfo->r_value = (*rel->sym_ptr_ptr)->udata.i;
 232         }
 233       break;
 234     case BFD_RELOC_MACH_O_SECTDIFF:
 235       rinfo->r_scattered = 1;
 236       rinfo->r_type = BFD_MACH_O_GENERIC_RELOC_SECTDIFF;
 237       rinfo->r_pcrel = 0;
 238       rinfo->r_length = rel->howto->size;
 239       rinfo->r_extern = 0;
 240       rinfo->r_value = rel->addend;
 241       break;
 242     case BFD_RELOC_MACH_O_LOCAL_SECTDIFF:
 243       rinfo->r_scattered = 1;
 244       rinfo->r_type = BFD_MACH_O_GENERIC_RELOC_LOCAL_SECTDIFF;
 245       rinfo->r_pcrel = 0;
 246       rinfo->r_length = rel->howto->size;
 247       rinfo->r_extern = 0;
 248       rinfo->r_value = rel->addend;
 249       break;
 250     case BFD_RELOC_MACH_O_PAIR:
 251       rinfo->r_address = 0;
 252       rinfo->r_scattered = 1;
 253       rinfo->r_type = BFD_MACH_O_GENERIC_RELOC_PAIR;
 254       rinfo->r_pcrel = 0;
 255       rinfo->r_length = rel->howto->size;
 256       rinfo->r_extern = 0;
 257       rinfo->r_value = rel->addend;
 258       break;
 259     default:
 260       return FALSE;
 261     }
 262   return TRUE;
 263 }
 264
 265 static reloc_howto_type *
 266 bfd_mach_o_i386_bfd_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED,
 267                                        bfd_reloc_code_real_type code)
 268 {
 269   unsigned int i;
 270
 271   for (i = 0; i < sizeof (i386_howto_table) / sizeof (*i386_howto_table); i++)
 272     if (code == i386_howto_table[i].type)
 273       return &i386_howto_table[i];
 274   return NULL;
 275 }
 276
 277 static reloc_howto_type *
 278 bfd_mach_o_i386_bfd_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED,
 279                                        const char *name ATTRIBUTE_UNUSED)
 280 {
 281   return NULL;
 282 }
 283
 284 static bfd_boolean
 285 bfd_mach_o_i386_print_thread (bfd *abfd, bfd_mach_o_thread_flavour *thread,
 286                               void *vfile, char *buf)
 287 {
 288   FILE *file = (FILE *)vfile;
 289
 290   switch (thread->flavour)
 291     {
 292     case BFD_MACH_O_x86_THREAD_STATE:
 293       if (thread->size < (8 + 16 * 4))
 294         return FALSE;
 295       fprintf (file, "   x86_THREAD_STATE:\n");
 296       fprintf (file, "    flavor: 0x%08lx  count: 0x%08lx\n",
 297                (unsigned long)bfd_get_32 (abfd, buf + 0),
 298                (unsigned long)bfd_get_32 (abfd, buf + 4));
 299       fprintf (file, "     eax: %08lx  ebx: %08lx  ecx: %08lx  edx: %08lx\n",
 300                (unsigned long)bfd_get_32 (abfd, buf + 8),
 301                (unsigned long)bfd_get_32 (abfd, buf + 12),
 302                (unsigned long)bfd_get_32 (abfd, buf + 16),
 303                (unsigned long)bfd_get_32 (abfd, buf + 20));
 304       fprintf (file, "     edi: %08lx  esi: %08lx  ebp: %08lx  esp: %08lx\n",
 305                (unsigned long)bfd_get_32 (abfd, buf + 24),
 306                (unsigned long)bfd_get_32 (abfd, buf + 28),
 307                (unsigned long)bfd_get_32 (abfd, buf + 32),
 308                (unsigned long)bfd_get_32 (abfd, buf + 36));
 309       fprintf (file, "      ss: %08lx  flg: %08lx  eip: %08lx   cs: %08lx\n",
 310                (unsigned long)bfd_get_32 (abfd, buf + 40),
 311                (unsigned long)bfd_get_32 (abfd, buf + 44),
 312                (unsigned long)bfd_get_32 (abfd, buf + 48),
 313                (unsigned long)bfd_get_32 (abfd, buf + 52));
 314       fprintf (file, "      ds: %08lx   es: %08lx   fs: %08lx   gs: %08lx\n",
 315                (unsigned long)bfd_get_32 (abfd, buf + 56),
 316                (unsigned long)bfd_get_32 (abfd, buf + 60),
 317                (unsigned long)bfd_get_32 (abfd, buf + 64),
 318                (unsigned long)bfd_get_32 (abfd, buf + 68));
 319       return TRUE;
 320     case BFD_MACH_O_x86_FLOAT_STATE:
 321       if (thread->size < 8)
 322         return FALSE;
 323       fprintf (file, "   x86_FLOAT_STATE:\n");
 324       fprintf (file, "    flavor: 0x%08lx  count: 0x%08lx\n",
 325                (unsigned long)bfd_get_32 (abfd, buf + 0),
 326                (unsigned long)bfd_get_32 (abfd, buf + 4));
 327       return TRUE;
 328     case BFD_MACH_O_x86_EXCEPTION_STATE:
 329       if (thread->size < 8 + 3 * 4)
 330         return FALSE;
 331       fprintf (file, "   x86_EXCEPTION_STATE:\n");
 332       fprintf (file, "    flavor: 0x%08lx  count: 0x%08lx\n",
 333                (unsigned long)bfd_get_32 (abfd, buf + 0),
 334                (unsigned long)bfd_get_32 (abfd, buf + 4));
 335       fprintf (file, "    trapno: %08lx  err: %08lx  faultaddr: %08lx\n",
 336                (unsigned long)bfd_get_32 (abfd, buf + 8),
 337                (unsigned long)bfd_get_32 (abfd, buf + 12),
 338                (unsigned long)bfd_get_32 (abfd, buf + 16));
 339       return TRUE;
 340     default:
 341       break;
 342     }
 343   return FALSE;
 344 }
 345
 346 static const mach_o_section_name_xlat text_section_names_xlat[] =
 347   {
 348     {   ".symbol_stub",                 "__symbol_stub",
 349         SEC_CODE | SEC_LOAD,            BFD_MACH_O_S_SYMBOL_STUBS,
 350         BFD_MACH_O_S_ATTR_PURE_INSTRUCTIONS,
 351                                         0},
 352     {   ".picsymbol_stub",              "__picsymbol_stub",
 353         SEC_CODE | SEC_LOAD,            BFD_MACH_O_S_SYMBOL_STUBS,
 354         BFD_MACH_O_S_ATTR_PURE_INSTRUCTIONS,
 355                                         0},
 356     { NULL, NULL, 0, 0, 0, 0}
 357   };
 358
 359 static const mach_o_section_name_xlat data_section_names_xlat[] =
 360   {
 361     /* The first two are recognized by i386, but not emitted for x86 by
 362        modern GCC.  */
 363     {   ".non_lazy_symbol_pointer",     "__nl_symbol_ptr",
 364         SEC_DATA | SEC_LOAD,            BFD_MACH_O_S_NON_LAZY_SYMBOL_POINTERS,
 365         BFD_MACH_O_S_ATTR_NONE,         2},
 366     {   ".lazy_symbol_pointer",         "__la_symbol_ptr",
 367         SEC_DATA | SEC_LOAD,            BFD_MACH_O_S_LAZY_SYMBOL_POINTERS,
 368         BFD_MACH_O_S_ATTR_NONE,         2},
 369     {   ".lazy_symbol_pointer2",        "__la_sym_ptr2",
 370         SEC_DATA | SEC_LOAD,            BFD_MACH_O_S_LAZY_SYMBOL_POINTERS,
 371         BFD_MACH_O_S_ATTR_NONE,         2},
 372     {   ".lazy_symbol_pointer3",        "__la_sym_ptr3",
 373         SEC_DATA | SEC_LOAD,            BFD_MACH_O_S_LAZY_SYMBOL_POINTERS,
 374         BFD_MACH_O_S_ATTR_NONE,         2},
 375     { NULL, NULL, 0, 0, 0, 0}
 376   };
 377
 378 static const mach_o_section_name_xlat import_section_names_xlat[] =
 379   {
 380     {   ".picsymbol_stub3",             "__jump_table",
 381         SEC_CODE | SEC_LOAD,            BFD_MACH_O_S_SYMBOL_STUBS,
 382         BFD_MACH_O_S_ATTR_PURE_INSTRUCTIONS
 383         | BFD_MACH_O_S_SELF_MODIFYING_CODE,
 384                                         6},
 385     {   ".non_lazy_symbol_pointer_x86", "__pointers",
 386         SEC_DATA | SEC_LOAD,            BFD_MACH_O_S_NON_LAZY_SYMBOL_POINTERS,
 387         BFD_MACH_O_S_ATTR_NONE,         2},
 388     { NULL, NULL, 0, 0, 0, 0}
 389   };
 390
 391 const mach_o_segment_name_xlat mach_o_i386_segsec_names_xlat[] =
 392   {
 393     { "__TEXT", text_section_names_xlat },
 394     { "__DATA", data_section_names_xlat },
 395     { "__IMPORT", import_section_names_xlat },
 396     { NULL, NULL }
 397   };
 398
 399 #define bfd_mach_o_canonicalize_one_reloc  bfd_mach_o_i386_canonicalize_one_reloc
 400 #define bfd_mach_o_swap_reloc_out          bfd_mach_o_i386_swap_reloc_out
 401 #define bfd_mach_o_print_thread            bfd_mach_o_i386_print_thread
 402
 403 #define bfd_mach_o_tgt_seg_table mach_o_i386_segsec_names_xlat
 404 #define bfd_mach_o_section_type_valid_for_tgt NULL
 405
 406 #define bfd_mach_o_bfd_reloc_type_lookup bfd_mach_o_i386_bfd_reloc_type_lookup
 407 #define bfd_mach_o_bfd_reloc_name_lookup bfd_mach_o_i386_bfd_reloc_name_lookup
 408
 409 #define TARGET_NAME             i386_mach_o_vec
 410 #define TARGET_STRING           "mach-o-i386"
 411 #define TARGET_ARCHITECTURE     bfd_arch_i386
 412 #define TARGET_PAGESIZE         4096
 413 #define TARGET_BIG_ENDIAN       0
 414 #define TARGET_ARCHIVE          0
 415 #define TARGET_PRIORITY         0
 416 #include "mach-o-target.c"