1/* ELF support for BFD.
2   Copyright (C) 1991-2020 Free Software Foundation, Inc.
3
4   Written by Fred Fish @ Cygnus Support, from information published
5   in "UNIX System V Release 4, Programmers Guide: ANSI C and
6   Programming Support Tools".
7
8   This file is part of BFD, the Binary File Descriptor library.
9
10   This program is free software; you can redistribute it and/or modify
11   it under the terms of the GNU General Public License as published by
12   the Free Software Foundation; either version 3 of the License, or
13   (at your option) any later version.
14
15   This program is distributed in the hope that it will be useful,
16   but WITHOUT ANY WARRANTY; without even the implied warranty of
17   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18   GNU General Public License for more details.
19
20   You should have received a copy of the GNU General Public License
21   along with this program; if not, write to the Free Software
22   Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
23   MA 02110-1301, USA.  */
24
25/* This file is part of ELF support for BFD, and contains the portions
26   that describe how ELF is represented externally by the BFD library.
27   I.E. it describes the in-file representation of ELF.  It requires
28   the elf/common.h file which contains the portions that are common to
29   both the internal and external representations.  */
30
31/* The 64-bit stuff is kind of random.  Perhaps someone will publish a
32   spec someday.  */
33
34#ifndef _ELF_EXTERNAL_H
35#define _ELF_EXTERNAL_H
36
37/* Special section indices, which may show up in st_shndx fields, among
38   other places.  */
39
40#define SHN_LORESERVE	0xFF00		/* Begin range of reserved indices */
41#define SHN_LOPROC	0xFF00		/* Begin range of appl-specific */
42#define SHN_HIPROC	0xFF1F		/* End range of appl-specific */
43#define SHN_LOOS	0xFF20		/* OS specific semantics, lo */
44#define SHN_HIOS	0xFF3F		/* OS specific semantics, hi */
45#define SHN_ABS		0xFFF1		/* Associated symbol is absolute */
46#define SHN_COMMON	0xFFF2		/* Associated symbol is in common */
47#define SHN_XINDEX	0xFFFF		/* Section index is held elsewhere */
48#define SHN_HIRESERVE	0xFFFF		/* End range of reserved indices */
49
50/* ELF Header (32-bit implementations) */
51
52typedef struct {
53  unsigned char	e_ident[16];		/* ELF "magic number" */
54  unsigned char	e_type[2];		/* Identifies object file type */
55  unsigned char	e_machine[2];		/* Specifies required architecture */
56  unsigned char	e_version[4];		/* Identifies object file version */
57  unsigned char	e_entry[4];		/* Entry point virtual address */
58  unsigned char	e_phoff[4];		/* Program header table file offset */
59  unsigned char	e_shoff[4];		/* Section header table file offset */
60  unsigned char	e_flags[4];		/* Processor-specific flags */
61  unsigned char	e_ehsize[2];		/* ELF header size in bytes */
62  unsigned char	e_phentsize[2];		/* Program header table entry size */
63  unsigned char	e_phnum[2];		/* Program header table entry count */
64  unsigned char	e_shentsize[2];		/* Section header table entry size */
65  unsigned char	e_shnum[2];		/* Section header table entry count */
66  unsigned char	e_shstrndx[2];		/* Section header string table index */
67} Elf32_External_Ehdr;
68
69typedef struct {
70  unsigned char	e_ident[16];		/* ELF "magic number" */
71  unsigned char	e_type[2];		/* Identifies object file type */
72  unsigned char	e_machine[2];		/* Specifies required architecture */
73  unsigned char	e_version[4];		/* Identifies object file version */
74  unsigned char	e_entry[8];		/* Entry point virtual address */
75  unsigned char	e_phoff[8];		/* Program header table file offset */
76  unsigned char	e_shoff[8];		/* Section header table file offset */
77  unsigned char	e_flags[4];		/* Processor-specific flags */
78  unsigned char	e_ehsize[2];		/* ELF header size in bytes */
79  unsigned char	e_phentsize[2];		/* Program header table entry size */
80  unsigned char	e_phnum[2];		/* Program header table entry count */
81  unsigned char	e_shentsize[2];		/* Section header table entry size */
82  unsigned char	e_shnum[2];		/* Section header table entry count */
83  unsigned char	e_shstrndx[2];		/* Section header string table index */
84} Elf64_External_Ehdr;
85
86/* Program header */
87
88typedef struct {
89  unsigned char	p_type[4];		/* Identifies program segment type */
90  unsigned char	p_offset[4];		/* Segment file offset */
91  unsigned char	p_vaddr[4];		/* Segment virtual address */
92  unsigned char	p_paddr[4];		/* Segment physical address */
93  unsigned char	p_filesz[4];		/* Segment size in file */
94  unsigned char	p_memsz[4];		/* Segment size in memory */
95  unsigned char	p_flags[4];		/* Segment flags */
96  unsigned char	p_align[4];		/* Segment alignment, file & memory */
97} Elf32_External_Phdr;
98
99typedef struct {
100  unsigned char	p_type[4];		/* Identifies program segment type */
101  unsigned char	p_flags[4];		/* Segment flags */
102  unsigned char	p_offset[8];		/* Segment file offset */
103  unsigned char	p_vaddr[8];		/* Segment virtual address */
104  unsigned char	p_paddr[8];		/* Segment physical address */
105  unsigned char	p_filesz[8];		/* Segment size in file */
106  unsigned char	p_memsz[8];		/* Segment size in memory */
107  unsigned char	p_align[8];		/* Segment alignment, file & memory */
108} Elf64_External_Phdr;
109
110/* Section header */
111
112typedef struct {
113  unsigned char	sh_name[4];		/* Section name, index in string tbl */
114  unsigned char	sh_type[4];		/* Type of section */
115  unsigned char	sh_flags[4];		/* Miscellaneous section attributes */
116  unsigned char	sh_addr[4];		/* Section virtual addr at execution */
117  unsigned char	sh_offset[4];		/* Section file offset */
118  unsigned char	sh_size[4];		/* Size of section in bytes */
119  unsigned char	sh_link[4];		/* Index of another section */
120  unsigned char	sh_info[4];		/* Additional section information */
121  unsigned char	sh_addralign[4];	/* Section alignment */
122  unsigned char	sh_entsize[4];		/* Entry size if section holds table */
123} Elf32_External_Shdr;
124
125typedef struct {
126  unsigned char	sh_name[4];		/* Section name, index in string tbl */
127  unsigned char	sh_type[4];		/* Type of section */
128  unsigned char	sh_flags[8];		/* Miscellaneous section attributes */
129  unsigned char	sh_addr[8];		/* Section virtual addr at execution */
130  unsigned char	sh_offset[8];		/* Section file offset */
131  unsigned char	sh_size[8];		/* Size of section in bytes */
132  unsigned char	sh_link[4];		/* Index of another section */
133  unsigned char	sh_info[4];		/* Additional section information */
134  unsigned char	sh_addralign[8];	/* Section alignment */
135  unsigned char	sh_entsize[8];		/* Entry size if section holds table */
136} Elf64_External_Shdr;
137
138/* Compression header */
139
140typedef struct {
141  unsigned char	ch_type[4];		/* Type of compression */
142  unsigned char	ch_size[4];		/* Size of uncompressed data in bytes */
143  unsigned char	ch_addralign[4];	/* Alignment of uncompressed data  */
144} Elf32_External_Chdr;
145
146typedef struct {
147  unsigned char	ch_type[4];		/* Type of compression */
148  unsigned char	ch_reserved[4];		/* Padding */
149  unsigned char	ch_size[8];		/* Size of uncompressed data in bytes */
150  unsigned char	ch_addralign[8];	/* Alignment of uncompressed data  */
151} Elf64_External_Chdr;
152
153/* Symbol table entry */
154
155typedef struct {
156  unsigned char	st_name[4];		/* Symbol name, index in string tbl */
157  unsigned char	st_value[4];		/* Value of the symbol */
158  unsigned char	st_size[4];		/* Associated symbol size */
159  unsigned char	st_info[1];		/* Type and binding attributes */
160  unsigned char	st_other[1];		/* No defined meaning, 0 */
161  unsigned char	st_shndx[2];		/* Associated section index */
162} Elf32_External_Sym;
163
164typedef struct {
165  unsigned char	st_name[4];		/* Symbol name, index in string tbl */
166  unsigned char	st_info[1];		/* Type and binding attributes */
167  unsigned char	st_other[1];		/* No defined meaning, 0 */
168  unsigned char	st_shndx[2];		/* Associated section index */
169  unsigned char	st_value[8];		/* Value of the symbol */
170  unsigned char	st_size[8];		/* Associated symbol size */
171} Elf64_External_Sym;
172
173typedef struct {
174  unsigned char est_shndx[4];		/* Section index */
175} Elf_External_Sym_Shndx;
176
177/* Note segments */
178
179typedef struct {
180  unsigned char	namesz[4];		/* Size of entry's owner string */
181  unsigned char	descsz[4];		/* Size of the note descriptor */
182  unsigned char	type[4];		/* Interpretation of the descriptor */
183  char		name[1];		/* Start of the name+desc data */
184} Elf_External_Note;
185
186/* Align an address upward to a boundary, expressed as a number of bytes.
187   E.g. align to an 8-byte boundary with argument of 8.  */
188#define ELF_ALIGN_UP(addr, boundary) \
189  (((bfd_vma) (addr) + ((boundary) - 1)) & ~ (bfd_vma) ((boundary) -1))
190
191/* Compute the offset of the note descriptor from size of note entry's
192   owner string and note alignment.  */
193#define ELF_NOTE_DESC_OFFSET(namesz, align) \
194  ELF_ALIGN_UP (offsetof (Elf_External_Note, name) + (namesz), (align))
195
196/* Compute the offset of the next note entry from size of note entry's
197   owner string, size of the note descriptor and note alignment.  */
198#define ELF_NOTE_NEXT_OFFSET(namesz, descsz, align) \
199  ELF_ALIGN_UP (ELF_NOTE_DESC_OFFSET ((namesz), (align)) + (descsz), \
200		(align))
201
202/* Relocation Entries */
203typedef struct {
204  unsigned char r_offset[4];	/* Location at which to apply the action */
205  unsigned char	r_info[4];	/* index and type of relocation */
206} Elf32_External_Rel;
207
208typedef struct {
209  unsigned char r_offset[4];	/* Location at which to apply the action */
210  unsigned char	r_info[4];	/* index and type of relocation */
211  unsigned char	r_addend[4];	/* Constant addend used to compute value */
212} Elf32_External_Rela;
213
214typedef struct {
215  unsigned char r_offset[8];	/* Location at which to apply the action */
216  unsigned char	r_info[8];	/* index and type of relocation */
217} Elf64_External_Rel;
218
219typedef struct {
220  unsigned char r_offset[8];	/* Location at which to apply the action */
221  unsigned char	r_info[8];	/* index and type of relocation */
222  unsigned char	r_addend[8];	/* Constant addend used to compute value */
223} Elf64_External_Rela;
224
225/* dynamic section structure */
226
227typedef struct {
228  unsigned char	d_tag[4];		/* entry tag value */
229  union {
230    unsigned char	d_val[4];
231    unsigned char	d_ptr[4];
232  } d_un;
233} Elf32_External_Dyn;
234
235typedef struct {
236  unsigned char	d_tag[8];		/* entry tag value */
237  union {
238    unsigned char	d_val[8];
239    unsigned char	d_ptr[8];
240  } d_un;
241} Elf64_External_Dyn;
242
243/* The version structures are currently size independent.  They are
244   named without a 32 or 64.  If that ever changes, these structures
245   will need to be renamed.  */
246
247/* This structure appears in a SHT_GNU_verdef section.  */
248
249typedef struct {
250  unsigned char		vd_version[2];
251  unsigned char		vd_flags[2];
252  unsigned char		vd_ndx[2];
253  unsigned char		vd_cnt[2];
254  unsigned char		vd_hash[4];
255  unsigned char		vd_aux[4];
256  unsigned char		vd_next[4];
257} Elf_External_Verdef;
258
259/* This structure appears in a SHT_GNU_verdef section.  */
260
261typedef struct {
262  unsigned char		vda_name[4];
263  unsigned char		vda_next[4];
264} Elf_External_Verdaux;
265
266/* This structure appears in a SHT_GNU_verneed section.  */
267
268typedef struct {
269  unsigned char		vn_version[2];
270  unsigned char		vn_cnt[2];
271  unsigned char		vn_file[4];
272  unsigned char		vn_aux[4];
273  unsigned char		vn_next[4];
274} Elf_External_Verneed;
275
276/* This structure appears in a SHT_GNU_verneed section.  */
277
278typedef struct {
279  unsigned char		vna_hash[4];
280  unsigned char		vna_flags[2];
281  unsigned char		vna_other[2];
282  unsigned char		vna_name[4];
283  unsigned char		vna_next[4];
284} Elf_External_Vernaux;
285
286/* This structure appears in a SHT_GNU_versym section.  This is not a
287   standard ELF structure; ELF just uses Elf32_Half.  */
288
289typedef struct {
290  unsigned char		vs_vers[2];
291} ATTRIBUTE_PACKED  Elf_External_Versym;
292
293/* Structure for syminfo section.  */
294typedef struct
295{
296  unsigned char		si_boundto[2];
297  unsigned char		si_flags[2];
298} Elf_External_Syminfo;
299
300
301/* This structure appears on the stack and in NT_AUXV core file notes.  */
302typedef struct
303{
304  unsigned char		a_type[4];
305  unsigned char		a_val[4];
306} Elf32_External_Auxv;
307
308typedef struct
309{
310  unsigned char		a_type[8];
311  unsigned char		a_val[8];
312} Elf64_External_Auxv;
313
314/* Size of SHT_GROUP section entry.  */
315
316#define GRP_ENTRY_SIZE		4
317
318#endif /* _ELF_EXTERNAL_H */
319