bfd/mach-o-arm.c

   1 /* ARM Mach-O support for BFD.
   2    Copyright (C) 2015-2019 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/arm.h"
  27
  28 #define bfd_mach_o_object_p bfd_mach_o_arm_object_p
  29 #define bfd_mach_o_core_p bfd_mach_o_arm_core_p
  30 #define bfd_mach_o_mkobject bfd_mach_o_arm_mkobject
  31
  32 #define bfd_mach_o_canonicalize_one_reloc bfd_mach_o_arm_canonicalize_one_reloc
  33 #define bfd_mach_o_swap_reloc_out  NULL
  34 #define bfd_mach_o_bfd_reloc_type_lookup bfd_mach_o_arm_bfd_reloc_type_lookup
  35 #define bfd_mach_o_bfd_reloc_name_lookup bfd_mach_o_arm_bfd_reloc_name_lookup
  36
  37 #define bfd_mach_o_print_thread NULL
  38 #define bfd_mach_o_tgt_seg_table NULL
  39 #define bfd_mach_o_section_type_valid_for_tgt NULL
  40
  41 static const bfd_target *
  42 bfd_mach_o_arm_object_p (bfd *abfd)
  43 {
  44   return bfd_mach_o_header_p (abfd, 0, 0, BFD_MACH_O_CPU_TYPE_ARM);
  45 }
  46
  47 static const bfd_target *
  48 bfd_mach_o_arm_core_p (bfd *abfd)
  49 {
  50   return bfd_mach_o_header_p (abfd, 0,
  51                               BFD_MACH_O_MH_CORE, BFD_MACH_O_CPU_TYPE_ARM);
  52 }
  53
  54 static bfd_boolean
  55 bfd_mach_o_arm_mkobject (bfd *abfd)
  56 {
  57   bfd_mach_o_data_struct *mdata;
  58
  59   if (!bfd_mach_o_mkobject_init (abfd))
  60     return FALSE;
  61
  62   mdata = bfd_mach_o_get_data (abfd);
  63   mdata->header.magic = BFD_MACH_O_MH_MAGIC;
  64   mdata->header.cputype = BFD_MACH_O_CPU_TYPE_ARM;
  65   mdata->header.cpusubtype = BFD_MACH_O_CPU_SUBTYPE_ARM_ALL;
  66   mdata->header.byteorder = BFD_ENDIAN_LITTLE;
  67   mdata->header.version = 1;
  68
  69   return TRUE;
  70 }
  71
  72 static reloc_howto_type arm_howto_table[]=
  73 {
  74   /* 0 */
  75   HOWTO (BFD_RELOC_32, 0, 2, 32, FALSE, 0,
  76          complain_overflow_bitfield,
  77          NULL, "32",
  78          FALSE, 0xffffffff, 0xffffffff, FALSE),
  79   HOWTO (BFD_RELOC_16, 0, 1, 16, FALSE, 0,
  80          complain_overflow_bitfield,
  81          NULL, "16",
  82          FALSE, 0xffff, 0xffff, FALSE),
  83   HOWTO (BFD_RELOC_8, 0, 0, 8, FALSE, 0,
  84          complain_overflow_bitfield,
  85          NULL, "8",
  86          FALSE, 0xff, 0xff, FALSE),
  87   HOWTO (BFD_RELOC_32_PCREL, 0, 2, 32, TRUE, 0,
  88          complain_overflow_bitfield,
  89          NULL, "DISP32",
  90          FALSE, 0xffffffff, 0xffffffff, TRUE),
  91   /* 4 */
  92   HOWTO (BFD_RELOC_16_PCREL, 0, 1, 16, TRUE, 0,
  93          complain_overflow_bitfield,
  94          NULL, "DISP16",
  95          FALSE, 0xffff, 0xffff, TRUE),
  96   HOWTO (BFD_RELOC_MACH_O_SECTDIFF, 0, 2, 32, FALSE, 0,
  97          complain_overflow_bitfield,
  98          NULL, "SECTDIFF_32",
  99          FALSE, 0xffffffff, 0xffffffff, FALSE),
 100   HOWTO (BFD_RELOC_MACH_O_LOCAL_SECTDIFF, 0, 2, 32, FALSE, 0,
 101          complain_overflow_bitfield,
 102          NULL, "LSECTDIFF_32",
 103          FALSE, 0xffffffff, 0xffffffff, FALSE),
 104   HOWTO (BFD_RELOC_MACH_O_PAIR, 0, 2, 32, FALSE, 0,
 105          complain_overflow_bitfield,
 106          NULL, "PAIR_32",
 107          FALSE, 0xffffffff, 0xffffffff, FALSE),
 108   /* 8 */
 109   HOWTO (BFD_RELOC_MACH_O_SECTDIFF, 0, 1, 16, FALSE, 0,
 110          complain_overflow_bitfield,
 111          NULL, "SECTDIFF_16",
 112          FALSE, 0xffff, 0xffff, FALSE),
 113   HOWTO (BFD_RELOC_MACH_O_LOCAL_SECTDIFF, 0, 1, 16, FALSE, 0,
 114          complain_overflow_bitfield,
 115          NULL, "LSECTDIFF_16",
 116          FALSE, 0xffff, 0xffff, FALSE),
 117   HOWTO (BFD_RELOC_MACH_O_PAIR, 0, 1, 16, FALSE, 0,
 118          complain_overflow_bitfield,
 119          NULL, "PAIR_16",
 120          FALSE, 0xffff, 0xffff, FALSE),
 121   HOWTO (BFD_RELOC_ARM_PCREL_CALL, 2, 2, 24, TRUE, 0,
 122          complain_overflow_signed,
 123          NULL, "BR24",
 124          FALSE, 0x00ffffff, 0x00ffffff, TRUE),
 125   /* 12 */
 126   HOWTO (BFD_RELOC_ARM_MOVW, 0, 2, 16, FALSE, 0,
 127          complain_overflow_dont,
 128          NULL, "MOVW",
 129          FALSE, 0x000f0fff, 0x000f0fff, FALSE),
 130   HOWTO (BFD_RELOC_MACH_O_PAIR, 0, 2, 16, FALSE, 0,
 131          complain_overflow_bitfield,
 132          NULL, "PAIR_W",
 133          FALSE, 0x000f0fff, 0x000f0fff, FALSE),
 134   HOWTO (BFD_RELOC_ARM_MOVT, 0, 2, 16, FALSE, 0,
 135          complain_overflow_bitfield,
 136          NULL, "MOVT",
 137          FALSE, 0x000f0fff, 0x000f0fff, FALSE),
 138   HOWTO (BFD_RELOC_MACH_O_PAIR, 0, 2, 16, FALSE, 0,
 139          complain_overflow_bitfield,
 140          NULL, "PAIR_T",
 141          FALSE, 0x000f0fff, 0x000f0fff, FALSE),
 142   /* 16 */
 143   HOWTO (BFD_RELOC_THUMB_PCREL_BLX, 2, 2, 24, TRUE, 0,
 144          complain_overflow_signed,
 145          NULL, "TBR22",
 146          FALSE, 0x07ff2fff, 0x07ff2fff, TRUE)
 147 };
 148
 149 static bfd_boolean
 150 bfd_mach_o_arm_canonicalize_one_reloc (bfd *       abfd,
 151                                        struct mach_o_reloc_info_external * raw,
 152                                        arelent *   res,
 153                                        asymbol **  syms,
 154                                        arelent *   res_base)
 155 {
 156   bfd_mach_o_reloc_info reloc;
 157
 158   if (!bfd_mach_o_pre_canonicalize_one_reloc (abfd, raw, &reloc, res, syms))
 159     return FALSE;
 160
 161   if (reloc.r_scattered)
 162     {
 163       switch (reloc.r_type)
 164         {
 165         case BFD_MACH_O_ARM_RELOC_PAIR:
 166           /* PR 21813: Check for a corrupt PAIR reloc at the start.  */
 167           if (res == res_base)
 168             return FALSE;
 169           if (reloc.r_length == 2)
 170             {
 171               res->howto = &arm_howto_table[7];
 172               res->address = res[-1].address;
 173               return TRUE;
 174             }
 175           else if (reloc.r_length == 1)
 176             {
 177               res->howto = &arm_howto_table[10];
 178               res->address = res[-1].address;
 179               return TRUE;
 180             }
 181           return FALSE;
 182
 183         case BFD_MACH_O_ARM_RELOC_SECTDIFF:
 184           if (reloc.r_length == 2)
 185             {
 186               res->howto = &arm_howto_table[5];
 187               return TRUE;
 188             }
 189           else if (reloc.r_length == 1)
 190             {
 191               res->howto = &arm_howto_table[8];
 192               return TRUE;
 193             }
 194           return FALSE;
 195
 196         case BFD_MACH_O_ARM_RELOC_LOCAL_SECTDIFF:
 197           if (reloc.r_length == 2)
 198             {
 199               res->howto = &arm_howto_table[6];
 200               return TRUE;
 201             }
 202           else if (reloc.r_length == 1)
 203             {
 204               res->howto = &arm_howto_table[9];
 205               return TRUE;
 206             }
 207           return FALSE;
 208
 209         case BFD_MACH_O_ARM_RELOC_HALF_SECTDIFF:
 210           switch (reloc.r_length)
 211             {
 212             case 2: /* :lower16: for movw arm.  */
 213               res->howto = &arm_howto_table[12];
 214               return TRUE;
 215             case 3: /* :upper16: for movt arm.  */
 216               res->howto = &arm_howto_table[14];
 217               return TRUE;
 218             }
 219           return FALSE;
 220
 221         default:
 222           break;
 223         }
 224     }
 225   else
 226     {
 227       switch (reloc.r_type)
 228         {
 229         case BFD_MACH_O_ARM_RELOC_VANILLA:
 230           switch ((reloc.r_length << 1) | reloc.r_pcrel)
 231             {
 232             case 0: /* len = 0, pcrel = 0  */
 233               res->howto = &arm_howto_table[2];
 234               return TRUE;
 235             case 2: /* len = 1, pcrel = 0  */
 236               res->howto = &arm_howto_table[1];
 237               return TRUE;
 238             case 3: /* len = 1, pcrel = 1  */
 239               res->howto = &arm_howto_table[4];
 240               return TRUE;
 241             case 4: /* len = 2, pcrel = 0  */
 242               res->howto = &arm_howto_table[0];
 243               return TRUE;
 244             case 5: /* len = 2, pcrel = 1  */
 245               res->howto = &arm_howto_table[3];
 246               return TRUE;
 247             default:
 248               return FALSE;
 249             }
 250           break;
 251
 252         case BFD_MACH_O_ARM_RELOC_BR24:
 253           if (reloc.r_length == 2 && reloc.r_pcrel == 1)
 254             {
 255               res->howto = &arm_howto_table[11];
 256               return TRUE;
 257             }
 258           break;
 259
 260         case BFD_MACH_O_THUMB_RELOC_BR22:
 261           if (reloc.r_length == 2 && reloc.r_pcrel == 1)
 262             {
 263               res->howto = &arm_howto_table[16];
 264               return TRUE;
 265             }
 266           break;
 267
 268         case BFD_MACH_O_ARM_RELOC_HALF:
 269           if (reloc.r_pcrel == 0)
 270             switch (reloc.r_length)
 271               {
 272               case 0: /* :lower16: for movw arm.  */
 273                 res->howto = &arm_howto_table[12];
 274                 return TRUE;
 275               case 1: /* :upper16: for movt arm.  */
 276                 res->howto = &arm_howto_table[14];
 277                 return TRUE;
 278               }
 279           break;
 280
 281         case BFD_MACH_O_ARM_RELOC_PAIR:
 282           if (res[-1].howto == &arm_howto_table[12]
 283               && reloc.r_length == 0)
 284             {
 285               /* Pair for :lower16: of movw arm.  */
 286               res->howto = &arm_howto_table[13];
 287               /* This reloc contains the other half in its r_address field.  */
 288               res[-1].addend += (res->address & 0xffff) << 16;
 289               res->address = res[-1].address;
 290               return TRUE;
 291             }
 292           else if (res[-1].howto == &arm_howto_table[14]
 293                    && reloc.r_length == 1)
 294             {
 295               /* Pair for :upper16: of movt arm.  */
 296               res->howto = &arm_howto_table[15];
 297               /* This reloc contains the other half in its r_address field.  */
 298               res[-1].addend += res->address & 0xffff;
 299               res->address = res[-1].address;
 300               return TRUE;
 301             }
 302           break;
 303
 304         default:
 305           break;
 306         }
 307     }
 308
 309   return FALSE;
 310 }
 311
 312 static reloc_howto_type *
 313 bfd_mach_o_arm_bfd_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED,
 314                                       bfd_reloc_code_real_type code)
 315 {
 316   unsigned int i;
 317
 318   for (i = 0; i < sizeof (arm_howto_table) / sizeof (*arm_howto_table); i++)
 319     if (code == arm_howto_table[i].type)
 320       return &arm_howto_table[i];
 321   return NULL;
 322 }
 323
 324 static reloc_howto_type *
 325 bfd_mach_o_arm_bfd_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED,
 326                                       const char *name ATTRIBUTE_UNUSED)
 327 {
 328   return NULL;
 329 }
 330
 331 #define TARGET_NAME             arm_mach_o_vec
 332 #define TARGET_STRING           "mach-o-arm"
 333 #define TARGET_ARCHITECTURE     bfd_arch_arm
 334 #define TARGET_PAGESIZE         4096
 335 #define TARGET_BIG_ENDIAN       0
 336 #define TARGET_ARCHIVE          0
 337 #define TARGET_PRIORITY         0
 338 #include "mach-o-target.c"