1 /* ELF support for BFD.
2    Copyright 1991, 1992, 1993, 1995, 1997, 1998, 1999, 2001, 2003, 2005
3    Free Software Foundation, Inc.
4 
5    Written by Fred Fish @ Cygnus Support, from information published
6    in "UNIX System V Release 4, Programmers Guide: ANSI C and
7    Programming Support Tools".
8 
9 This file is part of BFD, the Binary File Descriptor library.
10 
11 This program is free software; you can redistribute it and/or modify
12 it under the terms of the GNU General Public License as published by
13 the Free Software Foundation; either version 2 of the License, or
14 (at your option) any later version.
15 
16 This program is distributed in the hope that it will be useful,
17 but WITHOUT ANY WARRANTY; without even the implied warranty of
18 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19 GNU General Public License for more details.
20 
21 You should have received a copy of the GNU General Public License
22 along with this program; if not, write to the Free Software
23 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.  */
24 
25 
26 /* This file is part of ELF support for BFD, and contains the portions
27    that describe how ELF is represented externally by the BFD library.
28    I.E. it describes the in-file representation of ELF.  It requires
29    the elf/common.h file which contains the portions that are common to
30    both the internal and external representations. */
31 
32 /* The 64-bit stuff is kind of random.  Perhaps someone will publish a
33    spec someday.  */
34 
35 #ifndef _ELF_EXTERNAL_H
36 #define _ELF_EXTERNAL_H
37 
38 /* ELF Header (32-bit implementations) */
39 
40 typedef struct {
41   unsigned char	e_ident[16];		/* ELF "magic number" */
42   unsigned char	e_type[2];		/* Identifies object file type */
43   unsigned char	e_machine[2];		/* Specifies required architecture */
44   unsigned char	e_version[4];		/* Identifies object file version */
45   unsigned char	e_entry[4];		/* Entry point virtual address */
46   unsigned char	e_phoff[4];		/* Program header table file offset */
47   unsigned char	e_shoff[4];		/* Section header table file offset */
48   unsigned char	e_flags[4];		/* Processor-specific flags */
49   unsigned char	e_ehsize[2];		/* ELF header size in bytes */
50   unsigned char	e_phentsize[2];		/* Program header table entry size */
51   unsigned char	e_phnum[2];		/* Program header table entry count */
52   unsigned char	e_shentsize[2];		/* Section header table entry size */
53   unsigned char	e_shnum[2];		/* Section header table entry count */
54   unsigned char	e_shstrndx[2];		/* Section header string table index */
55 } Elf32_External_Ehdr;
56 
57 typedef struct {
58   unsigned char	e_ident[16];		/* ELF "magic number" */
59   unsigned char	e_type[2];		/* Identifies object file type */
60   unsigned char	e_machine[2];		/* Specifies required architecture */
61   unsigned char	e_version[4];		/* Identifies object file version */
62   unsigned char	e_entry[8];		/* Entry point virtual address */
63   unsigned char	e_phoff[8];		/* Program header table file offset */
64   unsigned char	e_shoff[8];		/* Section header table file offset */
65   unsigned char	e_flags[4];		/* Processor-specific flags */
66   unsigned char	e_ehsize[2];		/* ELF header size in bytes */
67   unsigned char	e_phentsize[2];		/* Program header table entry size */
68   unsigned char	e_phnum[2];		/* Program header table entry count */
69   unsigned char	e_shentsize[2];		/* Section header table entry size */
70   unsigned char	e_shnum[2];		/* Section header table entry count */
71   unsigned char	e_shstrndx[2];		/* Section header string table index */
72 } Elf64_External_Ehdr;
73 
74 /* Program header */
75 
76 typedef struct {
77   unsigned char	p_type[4];		/* Identifies program segment type */
78   unsigned char	p_offset[4];		/* Segment file offset */
79   unsigned char	p_vaddr[4];		/* Segment virtual address */
80   unsigned char	p_paddr[4];		/* Segment physical address */
81   unsigned char	p_filesz[4];		/* Segment size in file */
82   unsigned char	p_memsz[4];		/* Segment size in memory */
83   unsigned char	p_flags[4];		/* Segment flags */
84   unsigned char	p_align[4];		/* Segment alignment, file & memory */
85 } Elf32_External_Phdr;
86 
87 typedef struct {
88   unsigned char	p_type[4];		/* Identifies program segment type */
89   unsigned char	p_flags[4];		/* Segment flags */
90   unsigned char	p_offset[8];		/* Segment file offset */
91   unsigned char	p_vaddr[8];		/* Segment virtual address */
92   unsigned char	p_paddr[8];		/* Segment physical address */
93   unsigned char	p_filesz[8];		/* Segment size in file */
94   unsigned char	p_memsz[8];		/* Segment size in memory */
95   unsigned char	p_align[8];		/* Segment alignment, file & memory */
96 } Elf64_External_Phdr;
97 
98 /* Section header */
99 
100 typedef struct {
101   unsigned char	sh_name[4];		/* Section name, index in string tbl */
102   unsigned char	sh_type[4];		/* Type of section */
103   unsigned char	sh_flags[4];		/* Miscellaneous section attributes */
104   unsigned char	sh_addr[4];		/* Section virtual addr at execution */
105   unsigned char	sh_offset[4];		/* Section file offset */
106   unsigned char	sh_size[4];		/* Size of section in bytes */
107   unsigned char	sh_link[4];		/* Index of another section */
108   unsigned char	sh_info[4];		/* Additional section information */
109   unsigned char	sh_addralign[4];	/* Section alignment */
110   unsigned char	sh_entsize[4];		/* Entry size if section holds table */
111 } Elf32_External_Shdr;
112 
113 typedef struct {
114   unsigned char	sh_name[4];		/* Section name, index in string tbl */
115   unsigned char	sh_type[4];		/* Type of section */
116   unsigned char	sh_flags[8];		/* Miscellaneous section attributes */
117   unsigned char	sh_addr[8];		/* Section virtual addr at execution */
118   unsigned char	sh_offset[8];		/* Section file offset */
119   unsigned char	sh_size[8];		/* Size of section in bytes */
120   unsigned char	sh_link[4];		/* Index of another section */
121   unsigned char	sh_info[4];		/* Additional section information */
122   unsigned char	sh_addralign[8];	/* Section alignment */
123   unsigned char	sh_entsize[8];		/* Entry size if section holds table */
124 } Elf64_External_Shdr;
125 
126 /* Symbol table entry */
127 
128 typedef struct {
129   unsigned char	st_name[4];		/* Symbol name, index in string tbl */
130   unsigned char	st_value[4];		/* Value of the symbol */
131   unsigned char	st_size[4];		/* Associated symbol size */
132   unsigned char	st_info[1];		/* Type and binding attributes */
133   unsigned char	st_other[1];		/* No defined meaning, 0 */
134   unsigned char	st_shndx[2];		/* Associated section index */
135 } Elf32_External_Sym;
136 
137 typedef struct {
138   unsigned char	st_name[4];		/* Symbol name, index in string tbl */
139   unsigned char	st_info[1];		/* Type and binding attributes */
140   unsigned char	st_other[1];		/* No defined meaning, 0 */
141   unsigned char	st_shndx[2];		/* Associated section index */
142   unsigned char	st_value[8];		/* Value of the symbol */
143   unsigned char	st_size[8];		/* Associated symbol size */
144 } Elf64_External_Sym;
145 
146 typedef struct {
147   unsigned char est_shndx[4];		/* Section index */
148 } Elf_External_Sym_Shndx;
149 
150 /* Note segments */
151 
152 typedef struct {
153   unsigned char	namesz[4];		/* Size of entry's owner string */
154   unsigned char	descsz[4];		/* Size of the note descriptor */
155   unsigned char	type[4];		/* Interpretation of the descriptor */
156   char		name[1];		/* Start of the name+desc data */
157 } Elf_External_Note;
158 
159 /* Relocation Entries */
160 typedef struct {
161   unsigned char r_offset[4];	/* Location at which to apply the action */
162   unsigned char	r_info[4];	/* index and type of relocation */
163 } Elf32_External_Rel;
164 
165 typedef struct {
166   unsigned char r_offset[4];	/* Location at which to apply the action */
167   unsigned char	r_info[4];	/* index and type of relocation */
168   unsigned char	r_addend[4];	/* Constant addend used to compute value */
169 } Elf32_External_Rela;
170 
171 typedef struct {
172   unsigned char r_offset[8];	/* Location at which to apply the action */
173   unsigned char	r_info[8];	/* index and type of relocation */
174 } Elf64_External_Rel;
175 
176 typedef struct {
177   unsigned char r_offset[8];	/* Location at which to apply the action */
178   unsigned char	r_info[8];	/* index and type of relocation */
179   unsigned char	r_addend[8];	/* Constant addend used to compute value */
180 } Elf64_External_Rela;
181 
182 typedef unsigned char Elf32_External_Relr[4];
183 typedef unsigned char Elf64_External_Relr[8];
184 
185 /* dynamic section structure */
186 
187 typedef struct {
188   unsigned char	d_tag[4];		/* entry tag value */
189   union {
190     unsigned char	d_val[4];
191     unsigned char	d_ptr[4];
192   } d_un;
193 } Elf32_External_Dyn;
194 
195 typedef struct {
196   unsigned char	d_tag[8];		/* entry tag value */
197   union {
198     unsigned char	d_val[8];
199     unsigned char	d_ptr[8];
200   } d_un;
201 } Elf64_External_Dyn;
202 
203 /* The version structures are currently size independent.  They are
204    named without a 32 or 64.  If that ever changes, these structures
205    will need to be renamed.  */
206 
207 /* This structure appears in a SHT_GNU_verdef section.  */
208 
209 typedef struct {
210   unsigned char		vd_version[2];
211   unsigned char		vd_flags[2];
212   unsigned char		vd_ndx[2];
213   unsigned char		vd_cnt[2];
214   unsigned char		vd_hash[4];
215   unsigned char		vd_aux[4];
216   unsigned char		vd_next[4];
217 } Elf_External_Verdef;
218 
219 /* This structure appears in a SHT_GNU_verdef section.  */
220 
221 typedef struct {
222   unsigned char		vda_name[4];
223   unsigned char		vda_next[4];
224 } Elf_External_Verdaux;
225 
226 /* This structure appears in a SHT_GNU_verneed section.  */
227 
228 typedef struct {
229   unsigned char		vn_version[2];
230   unsigned char		vn_cnt[2];
231   unsigned char		vn_file[4];
232   unsigned char		vn_aux[4];
233   unsigned char		vn_next[4];
234 } Elf_External_Verneed;
235 
236 /* This structure appears in a SHT_GNU_verneed section.  */
237 
238 typedef struct {
239   unsigned char		vna_hash[4];
240   unsigned char		vna_flags[2];
241   unsigned char		vna_other[2];
242   unsigned char		vna_name[4];
243   unsigned char		vna_next[4];
244 } Elf_External_Vernaux;
245 
246 /* This structure appears in a SHT_GNU_versym section.  This is not a
247    standard ELF structure; ELF just uses Elf32_Half.  */
248 
249 typedef struct {
250   unsigned char		vs_vers[2];
251 }
252 #ifdef __GNUC__
253   __attribute__ ((packed))
254 #endif
255   Elf_External_Versym;
256 
257 /* Structure for syminfo section.  */
258 typedef struct
259 {
260   unsigned char		si_boundto[2];
261   unsigned char		si_flags[2];
262 } Elf_External_Syminfo;
263 
264 
265 /* This structure appears on the stack and in NT_AUXV core file notes.  */
266 typedef struct
267 {
268   unsigned char		a_type[4];
269   unsigned char		a_val[4];
270 } Elf32_External_Auxv;
271 
272 typedef struct
273 {
274   unsigned char		a_type[8];
275   unsigned char		a_val[8];
276 } Elf64_External_Auxv;
277 
278 /* Size of SHT_GROUP section entry.  */
279 
280 #define GRP_ENTRY_SIZE		4
281 
282 #endif /* _ELF_EXTERNAL_H */
283