1 /* Intel x86-64 Mach-O support for BFD.
2    Copyright (C) 2010-2021 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/x86-64.h"
27 
28 #define bfd_mach_o_object_p bfd_mach_o_x86_64_object_p
29 #define bfd_mach_o_core_p bfd_mach_o_x86_64_core_p
30 #define bfd_mach_o_mkobject bfd_mach_o_x86_64_mkobject
31 
32 static bfd_cleanup
bfd_mach_o_x86_64_object_p(bfd * abfd)33 bfd_mach_o_x86_64_object_p (bfd *abfd)
34 {
35   return bfd_mach_o_header_p (abfd, 0, 0, BFD_MACH_O_CPU_TYPE_X86_64);
36 }
37 
38 static bfd_cleanup
bfd_mach_o_x86_64_core_p(bfd * abfd)39 bfd_mach_o_x86_64_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_X86_64);
43 }
44 
45 static bool
bfd_mach_o_x86_64_mkobject(bfd * abfd)46 bfd_mach_o_x86_64_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_64;
55   mdata->header.cputype = BFD_MACH_O_CPU_TYPE_X86_64;
56   mdata->header.cpusubtype =
57     BFD_MACH_O_CPU_SUBTYPE_X86_ALL | BFD_MACH_O_CPU_SUBTYPE_LIB64;
58   mdata->header.byteorder = BFD_ENDIAN_LITTLE;
59   mdata->header.version = 2;
60 
61   return true;
62 }
63 
64 /* In case we're on a 32-bit machine, construct a 64-bit "-1" value.  */
65 #define MINUS_ONE (~ (bfd_vma) 0)
66 
67 static reloc_howto_type x86_64_howto_table[]=
68 {
69   /* 0 */
70   HOWTO(BFD_RELOC_64, 0, 4, 64, false, 0,
71 	complain_overflow_bitfield,
72 	NULL, "64",
73 	false, MINUS_ONE, MINUS_ONE, false),
74   HOWTO(BFD_RELOC_32, 0, 2, 32, false, 0,
75 	complain_overflow_bitfield,
76 	NULL, "32",
77 	false, 0xffffffff, 0xffffffff, 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   HOWTO(BFD_RELOC_MACH_O_X86_64_PCREL32_1, 0, 2, 32, true, 0,
83 	complain_overflow_bitfield,
84 	NULL, "DISP32_1",
85 	false, 0xffffffff, 0xffffffff, true),
86   /* 4 */
87   HOWTO(BFD_RELOC_MACH_O_X86_64_PCREL32_2, 0, 2, 32, true, 0,
88 	complain_overflow_bitfield,
89 	NULL, "DISP32_2",
90 	false, 0xffffffff, 0xffffffff, true),
91   HOWTO(BFD_RELOC_MACH_O_X86_64_PCREL32_4, 0, 2, 32, true, 0,
92 	complain_overflow_bitfield,
93 	NULL, "DISP32_4",
94 	false, 0xffffffff, 0xffffffff, true),
95   HOWTO(BFD_RELOC_MACH_O_X86_64_BRANCH32, 0, 2, 32, true, 0,
96 	complain_overflow_bitfield,
97 	NULL, "BRANCH32",
98 	false, 0xffffffff, 0xffffffff, true),
99   HOWTO(BFD_RELOC_MACH_O_X86_64_GOT_LOAD, 0, 2, 32, true, 0,
100 	complain_overflow_bitfield,
101 	NULL, "GOT_LOAD",
102 	false, 0xffffffff, 0xffffffff, true),
103   /* 8 */
104   HOWTO(BFD_RELOC_MACH_O_SUBTRACTOR32, 0, 2, 32, false, 0,
105 	complain_overflow_bitfield,
106 	NULL, "SUBTRACTOR32",
107 	false, 0xffffffff, 0xffffffff, false),
108   HOWTO(BFD_RELOC_MACH_O_SUBTRACTOR64, 0, 4, 64, false, 0,
109 	complain_overflow_bitfield,
110 	NULL, "SUBTRACTOR64",
111 	false, MINUS_ONE, MINUS_ONE, false),
112   HOWTO(BFD_RELOC_MACH_O_X86_64_GOT, 0, 2, 32, true, 0,
113 	complain_overflow_bitfield,
114 	NULL, "GOT",
115 	false, 0xffffffff, 0xffffffff, true),
116   HOWTO(BFD_RELOC_MACH_O_X86_64_BRANCH8, 0, 0, 8, true, 0,
117 	complain_overflow_bitfield,
118 	NULL, "BRANCH8",
119 	false, 0xff, 0xff, true),
120   /* 12 */
121   HOWTO(BFD_RELOC_MACH_O_X86_64_TLV, 0, 2, 32, true, 0,
122 	complain_overflow_bitfield,
123 	NULL, "TLV",
124 	false, 0xffffffff, 0xffffffff, true),
125 };
126 
127 static bool
bfd_mach_o_x86_64_canonicalize_one_reloc(bfd * abfd,struct mach_o_reloc_info_external * raw,arelent * res,asymbol ** syms,arelent * res_base ATTRIBUTE_UNUSED)128 bfd_mach_o_x86_64_canonicalize_one_reloc (bfd *       abfd,
129 					  struct mach_o_reloc_info_external * raw,
130 					  arelent *   res,
131 					  asymbol **  syms,
132 					  arelent *   res_base ATTRIBUTE_UNUSED)
133 {
134   bfd_mach_o_reloc_info reloc;
135 
136   if (!bfd_mach_o_pre_canonicalize_one_reloc (abfd, raw, &reloc, res, syms))
137     return false;
138 
139   /* On x86-64, scattered relocs are not used.  */
140   if (reloc.r_scattered)
141     return false;
142 
143   switch (reloc.r_type)
144     {
145     case BFD_MACH_O_X86_64_RELOC_UNSIGNED:
146       if (reloc.r_pcrel)
147 	return false;
148       switch (reloc.r_length)
149 	{
150 	case 2:
151 	  res->howto = &x86_64_howto_table[1];
152 	  return true;
153 	case 3:
154 	  res->howto = &x86_64_howto_table[0];
155 	  return true;
156 	default:
157 	  return false;
158 	}
159     case BFD_MACH_O_X86_64_RELOC_SIGNED:
160       if (reloc.r_length == 2 && reloc.r_pcrel)
161 	{
162 	  res->howto = &x86_64_howto_table[2];
163 	  return true;
164 	}
165       break;
166     case BFD_MACH_O_X86_64_RELOC_BRANCH:
167       if (!reloc.r_pcrel)
168 	return false;
169       switch (reloc.r_length)
170 	{
171 	case 2:
172 	  res->howto = &x86_64_howto_table[6];
173 	  return true;
174 	default:
175 	  return false;
176 	}
177       break;
178     case BFD_MACH_O_X86_64_RELOC_GOT_LOAD:
179       if (reloc.r_length == 2 && reloc.r_pcrel && reloc.r_extern)
180 	{
181 	  res->howto = &x86_64_howto_table[7];
182 	  return true;
183 	}
184       break;
185     case BFD_MACH_O_X86_64_RELOC_GOT:
186       if (reloc.r_length == 2 && reloc.r_pcrel && reloc.r_extern)
187 	{
188 	  res->howto = &x86_64_howto_table[10];
189 	  return true;
190 	}
191       break;
192     case BFD_MACH_O_X86_64_RELOC_SUBTRACTOR:
193       if (reloc.r_pcrel)
194 	return false;
195       switch (reloc.r_length)
196 	{
197 	case 2:
198 	  res->howto = &x86_64_howto_table[8];
199 	  return true;
200 	case 3:
201 	  res->howto = &x86_64_howto_table[9];
202 	  return true;
203 	default:
204 	  return false;
205 	}
206       break;
207     case BFD_MACH_O_X86_64_RELOC_SIGNED_1:
208       if (reloc.r_length == 2 && reloc.r_pcrel)
209 	{
210 	  res->howto = &x86_64_howto_table[3];
211 	  return true;
212 	}
213       break;
214     case BFD_MACH_O_X86_64_RELOC_SIGNED_2:
215       if (reloc.r_length == 2 && reloc.r_pcrel)
216 	{
217 	  res->howto = &x86_64_howto_table[4];
218 	  return true;
219 	}
220       break;
221     case BFD_MACH_O_X86_64_RELOC_SIGNED_4:
222       if (reloc.r_length == 2 && reloc.r_pcrel)
223 	{
224 	  res->howto = &x86_64_howto_table[5];
225 	  return true;
226 	}
227       break;
228     case BFD_MACH_O_X86_64_RELOC_TLV:
229       if (reloc.r_length == 2 && reloc.r_pcrel && reloc.r_extern)
230 	{
231 	  res->howto = &x86_64_howto_table[12];
232 	  return true;
233 	}
234       break;
235     default:
236       return false;
237     }
238   return false;
239 }
240 
241 static bool
bfd_mach_o_x86_64_swap_reloc_out(arelent * rel,bfd_mach_o_reloc_info * rinfo)242 bfd_mach_o_x86_64_swap_reloc_out (arelent *rel, bfd_mach_o_reloc_info *rinfo)
243 {
244   rinfo->r_address = rel->address;
245   rinfo->r_scattered = 0;
246   switch (rel->howto->type)
247     {
248     case BFD_RELOC_32:
249       rinfo->r_type = BFD_MACH_O_X86_64_RELOC_UNSIGNED;
250       rinfo->r_pcrel = 0;
251       rinfo->r_length = 2;
252       break;
253     case BFD_RELOC_64:
254       rinfo->r_type = BFD_MACH_O_X86_64_RELOC_UNSIGNED;
255       rinfo->r_pcrel = 0;
256       rinfo->r_length = 3;
257       break;
258     case BFD_RELOC_32_PCREL:
259       rinfo->r_type = BFD_MACH_O_X86_64_RELOC_SIGNED;
260       rinfo->r_pcrel = 1;
261       rinfo->r_length = 2;
262       break;
263     case BFD_RELOC_MACH_O_X86_64_PCREL32_1:
264       rinfo->r_type = BFD_MACH_O_X86_64_RELOC_SIGNED_1;
265       rinfo->r_pcrel = 1;
266       rinfo->r_length = 2;
267       break;
268     case BFD_RELOC_MACH_O_X86_64_PCREL32_2:
269       rinfo->r_type = BFD_MACH_O_X86_64_RELOC_SIGNED_2;
270       rinfo->r_pcrel = 1;
271       rinfo->r_length = 2;
272       break;
273     case BFD_RELOC_MACH_O_X86_64_PCREL32_4:
274       rinfo->r_type = BFD_MACH_O_X86_64_RELOC_SIGNED_4;
275       rinfo->r_pcrel = 1;
276       rinfo->r_length = 2;
277       break;
278     case BFD_RELOC_MACH_O_X86_64_BRANCH32:
279       rinfo->r_type = BFD_MACH_O_X86_64_RELOC_BRANCH;
280       rinfo->r_pcrel = 1;
281       rinfo->r_length = 2;
282       break;
283     case BFD_RELOC_MACH_O_SUBTRACTOR32:
284       rinfo->r_type = BFD_MACH_O_X86_64_RELOC_SUBTRACTOR;
285       rinfo->r_pcrel = 0;
286       rinfo->r_length = 2;
287       break;
288     case BFD_RELOC_MACH_O_SUBTRACTOR64:
289       rinfo->r_type = BFD_MACH_O_X86_64_RELOC_SUBTRACTOR;
290       rinfo->r_pcrel = 0;
291       rinfo->r_length = 3;
292       break;
293     case BFD_RELOC_MACH_O_X86_64_GOT:
294       rinfo->r_type = BFD_MACH_O_X86_64_RELOC_GOT;
295       rinfo->r_pcrel = 1;
296       rinfo->r_length = 2;
297       break;
298     case BFD_RELOC_MACH_O_X86_64_GOT_LOAD:
299       rinfo->r_type = BFD_MACH_O_X86_64_RELOC_GOT_LOAD;
300       rinfo->r_pcrel = 1;
301       rinfo->r_length = 2;
302       break;
303     case BFD_RELOC_MACH_O_X86_64_TLV:
304       rinfo->r_type = BFD_MACH_O_X86_64_RELOC_TLV;
305       rinfo->r_pcrel = 1;
306       rinfo->r_length = 2;
307       break;
308     default:
309       return false;
310     }
311   if ((*rel->sym_ptr_ptr)->flags & BSF_SECTION_SYM)
312     {
313       rinfo->r_extern = 0;
314       rinfo->r_value =
315 	(*rel->sym_ptr_ptr)->section->output_section->target_index;
316     }
317   else
318     {
319       rinfo->r_extern = 1;
320       rinfo->r_value = (*rel->sym_ptr_ptr)->udata.i;
321     }
322   return true;
323 }
324 
325 static reloc_howto_type *
bfd_mach_o_x86_64_bfd_reloc_type_lookup(bfd * abfd ATTRIBUTE_UNUSED,bfd_reloc_code_real_type code)326 bfd_mach_o_x86_64_bfd_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED,
327 					 bfd_reloc_code_real_type code)
328 {
329   unsigned int i;
330 
331   for (i = 0;
332        i < sizeof (x86_64_howto_table) / sizeof (*x86_64_howto_table);
333        i++)
334     if (code == x86_64_howto_table[i].type)
335       return &x86_64_howto_table[i];
336   return NULL;
337 }
338 
339 static reloc_howto_type *
bfd_mach_o_x86_64_bfd_reloc_name_lookup(bfd * abfd ATTRIBUTE_UNUSED,const char * name ATTRIBUTE_UNUSED)340 bfd_mach_o_x86_64_bfd_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED,
341 					 const char *name ATTRIBUTE_UNUSED)
342 {
343   return NULL;
344 }
345 
346 static bool
bfd_mach_o_section_type_valid_for_x86_64(unsigned long val)347 bfd_mach_o_section_type_valid_for_x86_64 (unsigned long val)
348 {
349   if (val == BFD_MACH_O_S_NON_LAZY_SYMBOL_POINTERS
350       || val == BFD_MACH_O_S_LAZY_SYMBOL_POINTERS
351       || val == BFD_MACH_O_S_SYMBOL_STUBS)
352     return false;
353   return true;
354 }
355 
356 /* We want to bump the alignment of some sections.  */
357 static const mach_o_section_name_xlat text_section_names_xlat[] =
358   {
359     {	".eh_frame",				"__eh_frame",
360 	SEC_READONLY | SEC_DATA | SEC_LOAD,	BFD_MACH_O_S_COALESCED,
361 	BFD_MACH_O_S_ATTR_LIVE_SUPPORT
362 	| BFD_MACH_O_S_ATTR_STRIP_STATIC_SYMS
363 	| BFD_MACH_O_S_ATTR_NO_TOC,		3},
364     { NULL, NULL, 0, 0, 0, 0}
365   };
366 
367 const mach_o_segment_name_xlat mach_o_x86_64_segsec_names_xlat[] =
368   {
369     { "__TEXT", text_section_names_xlat },
370     { NULL, NULL }
371   };
372 
373 #define bfd_mach_o_canonicalize_one_reloc bfd_mach_o_x86_64_canonicalize_one_reloc
374 #define bfd_mach_o_swap_reloc_out bfd_mach_o_x86_64_swap_reloc_out
375 
376 #define bfd_mach_o_bfd_reloc_type_lookup bfd_mach_o_x86_64_bfd_reloc_type_lookup
377 #define bfd_mach_o_bfd_reloc_name_lookup bfd_mach_o_x86_64_bfd_reloc_name_lookup
378 #define bfd_mach_o_print_thread NULL
379 #define bfd_mach_o_tgt_seg_table mach_o_x86_64_segsec_names_xlat
380 #define bfd_mach_o_section_type_valid_for_tgt bfd_mach_o_section_type_valid_for_x86_64
381 
382 #define TARGET_NAME		x86_64_mach_o_vec
383 #define TARGET_STRING		"mach-o-x86-64"
384 #define TARGET_ARCHITECTURE	bfd_arch_i386
385 #define TARGET_PAGESIZE		4096
386 #define TARGET_BIG_ENDIAN	0
387 #define TARGET_ARCHIVE		0
388 #define TARGET_PRIORITY		0
389 #include "mach-o-target.c"
390