1/* Intel i386 Mach-O support for BFD.
2   Copyright (C) 2009-2017 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 "mach-o.h"
23#include "bfd.h"
24#include "libbfd.h"
25#include "libiberty.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
32static const bfd_target *
33bfd_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
38static const bfd_target *
39bfd_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
45static bfd_boolean
46bfd_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
63static 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
114static bfd_boolean
115bfd_mach_o_i386_canonicalize_one_reloc (bfd *abfd,
116				        struct mach_o_reloc_info_external *raw,
117					arelent *res, asymbol **syms)
118{
119  bfd_mach_o_reloc_info reloc;
120
121  if (!bfd_mach_o_pre_canonicalize_one_reloc (abfd, raw, &reloc, res, syms))
122    return FALSE;
123
124  if (reloc.r_scattered)
125    {
126      switch (reloc.r_type)
127        {
128        case BFD_MACH_O_GENERIC_RELOC_PAIR:
129          if (reloc.r_length == 2)
130            {
131	      res->howto = &i386_howto_table[7];
132	      res->address = res[-1].address;
133	      return TRUE;
134            }
135          else if (reloc.r_length == 1)
136	    {
137	      res->howto = &i386_howto_table[10];
138	      res->address = res[-1].address;
139	      return TRUE;
140	    }
141          return FALSE;
142        case BFD_MACH_O_GENERIC_RELOC_SECTDIFF:
143          if (reloc.r_length == 2)
144            {
145	      res->howto = &i386_howto_table[5];
146	      return TRUE;
147            }
148          else if (reloc.r_length == 1)
149            {
150	      res->howto = &i386_howto_table[8];
151	      return TRUE;
152            }
153          return FALSE;
154        case BFD_MACH_O_GENERIC_RELOC_LOCAL_SECTDIFF:
155          if (reloc.r_length == 2)
156            {
157	      res->howto = &i386_howto_table[6];
158	      return TRUE;
159            }
160          else if (reloc.r_length == 1)
161            {
162	      res->howto = &i386_howto_table[9];
163	      return TRUE;
164            }
165          return FALSE;
166        default:
167          return FALSE;
168        }
169    }
170  else
171    {
172      switch (reloc.r_type)
173        {
174        case BFD_MACH_O_GENERIC_RELOC_VANILLA:
175          switch ((reloc.r_length << 1) | reloc.r_pcrel)
176            {
177            case 0: /* len = 0, pcrel = 0  */
178              res->howto = &i386_howto_table[2];
179              return TRUE;
180            case 2: /* len = 1, pcrel = 0  */
181              res->howto = &i386_howto_table[1];
182              return TRUE;
183            case 3: /* len = 1, pcrel = 1  */
184              res->howto = &i386_howto_table[4];
185              return TRUE;
186            case 4: /* len = 2, pcrel = 0  */
187              res->howto = &i386_howto_table[0];
188              return TRUE;
189            case 5: /* len = 2, pcrel = 1  */
190              res->howto = &i386_howto_table[3];
191              return TRUE;
192            default:
193              return FALSE;
194            }
195          break;
196        default:
197          return FALSE;
198        }
199    }
200}
201
202static bfd_boolean
203bfd_mach_o_i386_swap_reloc_out (arelent *rel, bfd_mach_o_reloc_info *rinfo)
204{
205  rinfo->r_address = rel->address;
206  switch (rel->howto->type)
207    {
208    case BFD_RELOC_32:
209    case BFD_RELOC_32_PCREL:
210    case BFD_RELOC_16:
211    case BFD_RELOC_16_PCREL:
212    case BFD_RELOC_8:
213      rinfo->r_scattered = 0;
214      rinfo->r_type = BFD_MACH_O_GENERIC_RELOC_VANILLA;
215      rinfo->r_pcrel = rel->howto->pc_relative;
216      rinfo->r_length = rel->howto->size; /* Correct in practice.  */
217      if ((*rel->sym_ptr_ptr)->flags & BSF_SECTION_SYM)
218        {
219          rinfo->r_extern = 0;
220          rinfo->r_value =
221	    (*rel->sym_ptr_ptr)->section->output_section->target_index;
222        }
223      else
224        {
225          rinfo->r_extern = 1;
226          rinfo->r_value = (*rel->sym_ptr_ptr)->udata.i;
227        }
228      break;
229    case BFD_RELOC_MACH_O_SECTDIFF:
230      rinfo->r_scattered = 1;
231      rinfo->r_type = BFD_MACH_O_GENERIC_RELOC_SECTDIFF;
232      rinfo->r_pcrel = 0;
233      rinfo->r_length = rel->howto->size;
234      rinfo->r_extern = 0;
235      rinfo->r_value = rel->addend;
236      break;
237    case BFD_RELOC_MACH_O_LOCAL_SECTDIFF:
238      rinfo->r_scattered = 1;
239      rinfo->r_type = BFD_MACH_O_GENERIC_RELOC_LOCAL_SECTDIFF;
240      rinfo->r_pcrel = 0;
241      rinfo->r_length = rel->howto->size;
242      rinfo->r_extern = 0;
243      rinfo->r_value = rel->addend;
244      break;
245    case BFD_RELOC_MACH_O_PAIR:
246      rinfo->r_address = 0;
247      rinfo->r_scattered = 1;
248      rinfo->r_type = BFD_MACH_O_GENERIC_RELOC_PAIR;
249      rinfo->r_pcrel = 0;
250      rinfo->r_length = rel->howto->size;
251      rinfo->r_extern = 0;
252      rinfo->r_value = rel->addend;
253      break;
254    default:
255      return FALSE;
256    }
257  return TRUE;
258}
259
260static reloc_howto_type *
261bfd_mach_o_i386_bfd_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED,
262                                       bfd_reloc_code_real_type code)
263{
264  unsigned int i;
265
266  for (i = 0; i < sizeof (i386_howto_table) / sizeof (*i386_howto_table); i++)
267    if (code == i386_howto_table[i].type)
268      return &i386_howto_table[i];
269  return NULL;
270}
271
272static reloc_howto_type *
273bfd_mach_o_i386_bfd_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED,
274                                       const char *name ATTRIBUTE_UNUSED)
275{
276  return NULL;
277}
278
279static bfd_boolean
280bfd_mach_o_i386_print_thread (bfd *abfd, bfd_mach_o_thread_flavour *thread,
281                              void *vfile, char *buf)
282{
283  FILE *file = (FILE *)vfile;
284
285  switch (thread->flavour)
286    {
287    case BFD_MACH_O_x86_THREAD_STATE:
288      if (thread->size < (8 + 16 * 4))
289        return FALSE;
290      fprintf (file, "   x86_THREAD_STATE:\n");
291      fprintf (file, "    flavor: 0x%08lx  count: 0x%08lx\n",
292               (unsigned long)bfd_get_32 (abfd, buf + 0),
293               (unsigned long)bfd_get_32 (abfd, buf + 4));
294      fprintf (file, "     eax: %08lx  ebx: %08lx  ecx: %08lx  edx: %08lx\n",
295               (unsigned long)bfd_get_32 (abfd, buf + 8),
296               (unsigned long)bfd_get_32 (abfd, buf + 12),
297               (unsigned long)bfd_get_32 (abfd, buf + 16),
298               (unsigned long)bfd_get_32 (abfd, buf + 20));
299      fprintf (file, "     edi: %08lx  esi: %08lx  ebp: %08lx  esp: %08lx\n",
300               (unsigned long)bfd_get_32 (abfd, buf + 24),
301               (unsigned long)bfd_get_32 (abfd, buf + 28),
302               (unsigned long)bfd_get_32 (abfd, buf + 32),
303               (unsigned long)bfd_get_32 (abfd, buf + 36));
304      fprintf (file, "      ss: %08lx  flg: %08lx  eip: %08lx   cs: %08lx\n",
305               (unsigned long)bfd_get_32 (abfd, buf + 40),
306               (unsigned long)bfd_get_32 (abfd, buf + 44),
307               (unsigned long)bfd_get_32 (abfd, buf + 48),
308               (unsigned long)bfd_get_32 (abfd, buf + 52));
309      fprintf (file, "      ds: %08lx   es: %08lx   fs: %08lx   gs: %08lx\n",
310               (unsigned long)bfd_get_32 (abfd, buf + 56),
311               (unsigned long)bfd_get_32 (abfd, buf + 60),
312               (unsigned long)bfd_get_32 (abfd, buf + 64),
313               (unsigned long)bfd_get_32 (abfd, buf + 68));
314      return TRUE;
315    case BFD_MACH_O_x86_FLOAT_STATE:
316      if (thread->size < 8)
317        return FALSE;
318      fprintf (file, "   x86_FLOAT_STATE:\n");
319      fprintf (file, "    flavor: 0x%08lx  count: 0x%08lx\n",
320               (unsigned long)bfd_get_32 (abfd, buf + 0),
321               (unsigned long)bfd_get_32 (abfd, buf + 4));
322      return TRUE;
323    case BFD_MACH_O_x86_EXCEPTION_STATE:
324      if (thread->size < 8 + 3 * 4)
325        return FALSE;
326      fprintf (file, "   x86_EXCEPTION_STATE:\n");
327      fprintf (file, "    flavor: 0x%08lx  count: 0x%08lx\n",
328               (unsigned long)bfd_get_32 (abfd, buf + 0),
329               (unsigned long)bfd_get_32 (abfd, buf + 4));
330      fprintf (file, "    trapno: %08lx  err: %08lx  faultaddr: %08lx\n",
331               (unsigned long)bfd_get_32 (abfd, buf + 8),
332               (unsigned long)bfd_get_32 (abfd, buf + 12),
333               (unsigned long)bfd_get_32 (abfd, buf + 16));
334      return TRUE;
335    default:
336      break;
337    }
338  return FALSE;
339}
340
341static const mach_o_section_name_xlat text_section_names_xlat[] =
342  {
343    {	".symbol_stub",			"__symbol_stub",
344	SEC_CODE | SEC_LOAD,		BFD_MACH_O_S_SYMBOL_STUBS,
345	BFD_MACH_O_S_ATTR_PURE_INSTRUCTIONS,
346					0},
347    {	".picsymbol_stub",		"__picsymbol_stub",
348	SEC_CODE | SEC_LOAD,		BFD_MACH_O_S_SYMBOL_STUBS,
349	BFD_MACH_O_S_ATTR_PURE_INSTRUCTIONS,
350					0},
351    { NULL, NULL, 0, 0, 0, 0}
352  };
353
354static const mach_o_section_name_xlat data_section_names_xlat[] =
355  {
356    /* The first two are recognized by i386, but not emitted for x86 by
357       modern GCC.  */
358    {	".non_lazy_symbol_pointer",	"__nl_symbol_ptr",
359	SEC_DATA | SEC_LOAD,		BFD_MACH_O_S_NON_LAZY_SYMBOL_POINTERS,
360	BFD_MACH_O_S_ATTR_NONE,		2},
361    {	".lazy_symbol_pointer",		"__la_symbol_ptr",
362	SEC_DATA | SEC_LOAD,		BFD_MACH_O_S_LAZY_SYMBOL_POINTERS,
363	BFD_MACH_O_S_ATTR_NONE,		2},
364    {	".lazy_symbol_pointer2",	"__la_sym_ptr2",
365	SEC_DATA | SEC_LOAD,		BFD_MACH_O_S_LAZY_SYMBOL_POINTERS,
366	BFD_MACH_O_S_ATTR_NONE,		2},
367    {	".lazy_symbol_pointer3",	"__la_sym_ptr3",
368	SEC_DATA | SEC_LOAD,		BFD_MACH_O_S_LAZY_SYMBOL_POINTERS,
369	BFD_MACH_O_S_ATTR_NONE,		2},
370    { NULL, NULL, 0, 0, 0, 0}
371  };
372
373static const mach_o_section_name_xlat import_section_names_xlat[] =
374  {
375    {	".picsymbol_stub3",		"__jump_table",
376	SEC_CODE | SEC_LOAD,		BFD_MACH_O_S_SYMBOL_STUBS,
377	BFD_MACH_O_S_ATTR_PURE_INSTRUCTIONS
378	| BFD_MACH_O_S_SELF_MODIFYING_CODE,
379					6},
380    {	".non_lazy_symbol_pointer_x86",	"__pointers",
381	SEC_DATA | SEC_LOAD,		BFD_MACH_O_S_NON_LAZY_SYMBOL_POINTERS,
382	BFD_MACH_O_S_ATTR_NONE,		2},
383    { NULL, NULL, 0, 0, 0, 0}
384  };
385
386const mach_o_segment_name_xlat mach_o_i386_segsec_names_xlat[] =
387  {
388    { "__TEXT", text_section_names_xlat },
389    { "__DATA", data_section_names_xlat },
390    { "__IMPORT", import_section_names_xlat },
391    { NULL, NULL }
392  };
393
394#define bfd_mach_o_canonicalize_one_reloc bfd_mach_o_i386_canonicalize_one_reloc
395#define bfd_mach_o_swap_reloc_out bfd_mach_o_i386_swap_reloc_out
396#define bfd_mach_o_print_thread bfd_mach_o_i386_print_thread
397
398#define bfd_mach_o_tgt_seg_table mach_o_i386_segsec_names_xlat
399#define bfd_mach_o_section_type_valid_for_tgt NULL
400
401#define bfd_mach_o_bfd_reloc_type_lookup bfd_mach_o_i386_bfd_reloc_type_lookup
402#define bfd_mach_o_bfd_reloc_name_lookup bfd_mach_o_i386_bfd_reloc_name_lookup
403
404#define TARGET_NAME 		i386_mach_o_vec
405#define TARGET_STRING 		"mach-o-i386"
406#define TARGET_ARCHITECTURE	bfd_arch_i386
407#define TARGET_PAGESIZE		4096
408#define TARGET_BIG_ENDIAN 	0
409#define TARGET_ARCHIVE 		0
410#define TARGET_PRIORITY		0
411#include "mach-o-target.c"
412