Go to most recent revision | Details | Last modification | View Log | RSS feed
Rev | Author | Line No. | Line |
---|---|---|---|
5191 | serge | 1 | /* ELF support for BFD. |
2 | Copyright 1991, 1992, 1993, 1994, 1995, 1997, 1998, 2000, 2001, 2002, |
||
3 | 2003, 2006, 2007, 2008, 2010, 2011 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 3 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, |
||
24 | MA 02110-1301, USA. */ |
||
25 | |||
26 | /* This file is part of ELF support for BFD, and contains the portions |
||
27 | that describe how ELF is represented internally in the BFD library. |
||
28 | I.E. it describes the in-memory 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 | /* NOTE that these structures are not kept in the same order as they appear |
||
33 | in the object file. In some cases they've been reordered for more optimal |
||
34 | packing under various circumstances. */ |
||
35 | |||
36 | #ifndef _ELF_INTERNAL_H |
||
37 | #define _ELF_INTERNAL_H |
||
38 | |||
39 | /* Special section indices, which may show up in st_shndx fields, among |
||
40 | other places. */ |
||
41 | |||
42 | #undef SHN_UNDEF |
||
43 | #undef SHN_LORESERVE |
||
44 | #undef SHN_LOPROC |
||
45 | #undef SHN_HIPROC |
||
46 | #undef SHN_LOOS |
||
47 | #undef SHN_HIOS |
||
48 | #undef SHN_ABS |
||
49 | #undef SHN_COMMON |
||
50 | #undef SHN_XINDEX |
||
51 | #undef SHN_HIRESERVE |
||
52 | #define SHN_UNDEF 0 /* Undefined section reference */ |
||
53 | #define SHN_LORESERVE (-0x100u) /* Begin range of reserved indices */ |
||
54 | #define SHN_LOPROC (-0x100u) /* Begin range of appl-specific */ |
||
55 | #define SHN_HIPROC (-0xE1u) /* End range of appl-specific */ |
||
56 | #define SHN_LOOS (-0xE0u) /* OS specific semantics, lo */ |
||
57 | #define SHN_HIOS (-0xC1u) /* OS specific semantics, hi */ |
||
58 | #define SHN_ABS (-0xFu) /* Associated symbol is absolute */ |
||
59 | #define SHN_COMMON (-0xEu) /* Associated symbol is in common */ |
||
60 | #define SHN_XINDEX (-0x1u) /* Section index is held elsewhere */ |
||
61 | #define SHN_HIRESERVE (-0x1u) /* End range of reserved indices */ |
||
62 | #define SHN_BAD (-0x101u) /* Used internally by bfd */ |
||
63 | |||
64 | /* ELF Header */ |
||
65 | |||
66 | #define EI_NIDENT 16 /* Size of e_ident[] */ |
||
67 | |||
68 | typedef struct elf_internal_ehdr { |
||
69 | unsigned char e_ident[EI_NIDENT]; /* ELF "magic number" */ |
||
70 | bfd_vma e_entry; /* Entry point virtual address */ |
||
71 | bfd_size_type e_phoff; /* Program header table file offset */ |
||
72 | bfd_size_type e_shoff; /* Section header table file offset */ |
||
73 | unsigned long e_version; /* Identifies object file version */ |
||
74 | unsigned long e_flags; /* Processor-specific flags */ |
||
75 | unsigned short e_type; /* Identifies object file type */ |
||
76 | unsigned short e_machine; /* Specifies required architecture */ |
||
77 | unsigned int e_ehsize; /* ELF header size in bytes */ |
||
78 | unsigned int e_phentsize; /* Program header table entry size */ |
||
79 | unsigned int e_phnum; /* Program header table entry count */ |
||
80 | unsigned int e_shentsize; /* Section header table entry size */ |
||
81 | unsigned int e_shnum; /* Section header table entry count */ |
||
82 | unsigned int e_shstrndx; /* Section header string table index */ |
||
83 | } Elf_Internal_Ehdr; |
||
84 | |||
85 | /* Program header */ |
||
86 | |||
87 | struct elf_internal_phdr { |
||
88 | unsigned long p_type; /* Identifies program segment type */ |
||
89 | unsigned long p_flags; /* Segment flags */ |
||
90 | bfd_vma p_offset; /* Segment file offset */ |
||
91 | bfd_vma p_vaddr; /* Segment virtual address */ |
||
92 | bfd_vma p_paddr; /* Segment physical address */ |
||
93 | bfd_vma p_filesz; /* Segment size in file */ |
||
94 | bfd_vma p_memsz; /* Segment size in memory */ |
||
95 | bfd_vma p_align; /* Segment alignment, file & memory */ |
||
96 | }; |
||
97 | |||
98 | typedef struct elf_internal_phdr Elf_Internal_Phdr; |
||
99 | |||
100 | /* Section header */ |
||
101 | |||
102 | typedef struct elf_internal_shdr { |
||
103 | unsigned int sh_name; /* Section name, index in string tbl */ |
||
104 | unsigned int sh_type; /* Type of section */ |
||
105 | bfd_vma sh_flags; /* Miscellaneous section attributes */ |
||
106 | bfd_vma sh_addr; /* Section virtual addr at execution */ |
||
107 | file_ptr sh_offset; /* Section file offset */ |
||
108 | bfd_size_type sh_size; /* Size of section in bytes */ |
||
109 | unsigned int sh_link; /* Index of another section */ |
||
110 | unsigned int sh_info; /* Additional section information */ |
||
111 | bfd_vma sh_addralign; /* Section alignment */ |
||
112 | bfd_size_type sh_entsize; /* Entry size if section holds table */ |
||
113 | |||
114 | /* The internal rep also has some cached info associated with it. */ |
||
115 | asection * bfd_section; /* Associated BFD section. */ |
||
116 | unsigned char *contents; /* Section contents. */ |
||
117 | } Elf_Internal_Shdr; |
||
118 | |||
119 | /* Symbol table entry */ |
||
120 | |||
121 | struct elf_internal_sym { |
||
122 | bfd_vma st_value; /* Value of the symbol */ |
||
123 | bfd_vma st_size; /* Associated symbol size */ |
||
124 | unsigned long st_name; /* Symbol name, index in string tbl */ |
||
125 | unsigned char st_info; /* Type and binding attributes */ |
||
126 | unsigned char st_other; /* Visibilty, and target specific */ |
||
127 | unsigned char st_target_internal; /* Internal-only information */ |
||
128 | unsigned int st_shndx; /* Associated section index */ |
||
129 | }; |
||
130 | |||
131 | typedef struct elf_internal_sym Elf_Internal_Sym; |
||
132 | |||
133 | /* Note segments */ |
||
134 | |||
135 | typedef struct elf_internal_note { |
||
136 | unsigned long namesz; /* Size of entry's owner string */ |
||
137 | unsigned long descsz; /* Size of the note descriptor */ |
||
138 | unsigned long type; /* Interpretation of the descriptor */ |
||
139 | char * namedata; /* Start of the name+desc data */ |
||
140 | char * descdata; /* Start of the desc data */ |
||
141 | bfd_vma descpos; /* File offset of the descdata */ |
||
142 | } Elf_Internal_Note; |
||
143 | |||
144 | /* Relocation Entries */ |
||
145 | |||
146 | typedef struct elf_internal_rela { |
||
147 | bfd_vma r_offset; /* Location at which to apply the action */ |
||
148 | bfd_vma r_info; /* Index and Type of relocation */ |
||
149 | bfd_vma r_addend; /* Constant addend used to compute value */ |
||
150 | } Elf_Internal_Rela; |
||
151 | |||
152 | /* dynamic section structure */ |
||
153 | |||
154 | typedef struct elf_internal_dyn { |
||
155 | /* This needs to support 64-bit values in elf64. */ |
||
156 | bfd_vma d_tag; /* entry tag value */ |
||
157 | union { |
||
158 | /* This needs to support 64-bit values in elf64. */ |
||
159 | bfd_vma d_val; |
||
160 | bfd_vma d_ptr; |
||
161 | } d_un; |
||
162 | } Elf_Internal_Dyn; |
||
163 | |||
164 | /* This structure appears in a SHT_GNU_verdef section. */ |
||
165 | |||
166 | typedef struct elf_internal_verdef { |
||
167 | unsigned short vd_version; /* Version number of structure. */ |
||
168 | unsigned short vd_flags; /* Flags (VER_FLG_*). */ |
||
169 | unsigned short vd_ndx; /* Version index. */ |
||
170 | unsigned short vd_cnt; /* Number of verdaux entries. */ |
||
171 | unsigned long vd_hash; /* Hash of name. */ |
||
172 | unsigned long vd_aux; /* Offset to verdaux entries. */ |
||
173 | unsigned long vd_next; /* Offset to next verdef. */ |
||
174 | |||
175 | /* These fields are set up when BFD reads in the structure. FIXME: |
||
176 | It would be cleaner to store these in a different structure. */ |
||
177 | bfd *vd_bfd; /* BFD. */ |
||
178 | const char *vd_nodename; /* Version name. */ |
||
179 | struct elf_internal_verdef *vd_nextdef; /* vd_next as pointer. */ |
||
180 | struct elf_internal_verdaux *vd_auxptr; /* vd_aux as pointer. */ |
||
181 | unsigned int vd_exp_refno; /* Used by the linker. */ |
||
182 | } Elf_Internal_Verdef; |
||
183 | |||
184 | /* This structure appears in a SHT_GNU_verdef section. */ |
||
185 | |||
186 | typedef struct elf_internal_verdaux { |
||
187 | unsigned long vda_name; /* String table offset of name. */ |
||
188 | unsigned long vda_next; /* Offset to next verdaux. */ |
||
189 | |||
190 | /* These fields are set up when BFD reads in the structure. FIXME: |
||
191 | It would be cleaner to store these in a different structure. */ |
||
192 | const char *vda_nodename; /* vda_name as pointer. */ |
||
193 | struct elf_internal_verdaux *vda_nextptr; /* vda_next as pointer. */ |
||
194 | } Elf_Internal_Verdaux; |
||
195 | |||
196 | /* This structure appears in a SHT_GNU_verneed section. */ |
||
197 | |||
198 | typedef struct elf_internal_verneed { |
||
199 | unsigned short vn_version; /* Version number of structure. */ |
||
200 | unsigned short vn_cnt; /* Number of vernaux entries. */ |
||
201 | unsigned long vn_file; /* String table offset of library name. */ |
||
202 | unsigned long vn_aux; /* Offset to vernaux entries. */ |
||
203 | unsigned long vn_next; /* Offset to next verneed. */ |
||
204 | |||
205 | /* These fields are set up when BFD reads in the structure. FIXME: |
||
206 | It would be cleaner to store these in a different structure. */ |
||
207 | bfd *vn_bfd; /* BFD. */ |
||
208 | const char *vn_filename; /* vn_file as pointer. */ |
||
209 | struct elf_internal_vernaux *vn_auxptr; /* vn_aux as pointer. */ |
||
210 | struct elf_internal_verneed *vn_nextref; /* vn_nextref as pointer. */ |
||
211 | } Elf_Internal_Verneed; |
||
212 | |||
213 | /* This structure appears in a SHT_GNU_verneed section. */ |
||
214 | |||
215 | typedef struct elf_internal_vernaux { |
||
216 | unsigned long vna_hash; /* Hash of dependency name. */ |
||
217 | unsigned short vna_flags; /* Flags (VER_FLG_*). */ |
||
218 | unsigned short vna_other; /* Unused. */ |
||
219 | unsigned long vna_name; /* String table offset to version name. */ |
||
220 | unsigned long vna_next; /* Offset to next vernaux. */ |
||
221 | |||
222 | /* These fields are set up when BFD reads in the structure. FIXME: |
||
223 | It would be cleaner to store these in a different structure. */ |
||
224 | const char *vna_nodename; /* vna_name as pointer. */ |
||
225 | struct elf_internal_vernaux *vna_nextptr; /* vna_next as pointer. */ |
||
226 | } Elf_Internal_Vernaux; |
||
227 | |||
228 | /* This structure appears in a SHT_GNU_versym section. This is not a |
||
229 | standard ELF structure; ELF just uses Elf32_Half. */ |
||
230 | |||
231 | typedef struct elf_internal_versym { |
||
232 | unsigned short vs_vers; |
||
233 | } Elf_Internal_Versym; |
||
234 | |||
235 | /* Structure for syminfo section. */ |
||
236 | typedef struct |
||
237 | { |
||
238 | unsigned short int si_boundto; |
||
239 | unsigned short int si_flags; |
||
240 | } Elf_Internal_Syminfo; |
||
241 | |||
242 | /* This structure appears on the stack and in NT_AUXV core file notes. */ |
||
243 | typedef struct |
||
244 | { |
||
245 | bfd_vma a_type; |
||
246 | bfd_vma a_val; |
||
247 | } Elf_Internal_Auxv; |
||
248 | |||
249 | |||
250 | /* This structure is used to describe how sections should be assigned |
||
251 | to program segments. */ |
||
252 | |||
253 | struct elf_segment_map |
||
254 | { |
||
255 | /* Next program segment. */ |
||
256 | struct elf_segment_map *next; |
||
257 | /* Program segment type. */ |
||
258 | unsigned long p_type; |
||
259 | /* Program segment flags. */ |
||
260 | unsigned long p_flags; |
||
261 | /* Program segment physical address. */ |
||
262 | bfd_vma p_paddr; |
||
263 | /* Program segment virtual address offset from section vma. */ |
||
264 | bfd_vma p_vaddr_offset; |
||
265 | /* Program segment alignment. */ |
||
266 | bfd_vma p_align; |
||
267 | /* Segment size in file and memory */ |
||
268 | bfd_vma p_size; |
||
269 | /* Required size of filehdr + phdrs, if non-zero */ |
||
270 | bfd_vma header_size; |
||
271 | /* Whether the p_flags field is valid; if not, the flags are based |
||
272 | on the section flags. */ |
||
273 | unsigned int p_flags_valid : 1; |
||
274 | /* Whether the p_paddr field is valid; if not, the physical address |
||
275 | is based on the section lma values. */ |
||
276 | unsigned int p_paddr_valid : 1; |
||
277 | /* Whether the p_align field is valid; if not, PT_LOAD segment |
||
278 | alignment is based on the default maximum page size. */ |
||
279 | unsigned int p_align_valid : 1; |
||
280 | /* Whether the p_size field is valid; if not, the size are based |
||
281 | on the section sizes. */ |
||
282 | unsigned int p_size_valid : 1; |
||
283 | /* Whether this segment includes the file header. */ |
||
284 | unsigned int includes_filehdr : 1; |
||
285 | /* Whether this segment includes the program headers. */ |
||
286 | unsigned int includes_phdrs : 1; |
||
287 | /* Number of sections (may be 0). */ |
||
288 | unsigned int count; |
||
289 | /* Sections. Actual number of elements is in count field. */ |
||
290 | asection *sections[1]; |
||
291 | }; |
||
292 | |||
293 | /* .tbss is special. It doesn't contribute memory space to normal |
||
294 | segments and it doesn't take file space in normal segments. */ |
||
295 | #define ELF_TBSS_SPECIAL(sec_hdr, segment) \ |
||
296 | (((sec_hdr)->sh_flags & SHF_TLS) != 0 \ |
||
297 | && (sec_hdr)->sh_type == SHT_NOBITS \ |
||
298 | && (segment)->p_type != PT_TLS) |
||
299 | |||
300 | #define ELF_SECTION_SIZE(sec_hdr, segment) \ |
||
301 | (ELF_TBSS_SPECIAL(sec_hdr, segment) ? 0 : (sec_hdr)->sh_size) |
||
302 | |||
303 | /* Decide if the section SEC_HDR is in SEGMENT. If CHECK_VMA, then |
||
304 | VMAs are checked for alloc sections. If STRICT, then a zero size |
||
305 | section won't match at the end of a segment, unless the segment |
||
306 | is also zero size. Regardless of STRICT and CHECK_VMA, zero size |
||
307 | sections won't match at the start or end of PT_DYNAMIC, unless |
||
308 | PT_DYNAMIC is itself zero sized. */ |
||
309 | #define ELF_SECTION_IN_SEGMENT_1(sec_hdr, segment, check_vma, strict) \ |
||
310 | ((/* Only PT_LOAD, PT_GNU_RELRO and PT_TLS segments can contain \ |
||
311 | SHF_TLS sections. */ \ |
||
312 | ((((sec_hdr)->sh_flags & SHF_TLS) != 0) \ |
||
313 | && ((segment)->p_type == PT_TLS \ |
||
314 | || (segment)->p_type == PT_GNU_RELRO \ |
||
315 | || (segment)->p_type == PT_LOAD)) \ |
||
316 | /* PT_TLS segment contains only SHF_TLS sections, PT_PHDR no \ |
||
317 | sections at all. */ \ |
||
318 | || (((sec_hdr)->sh_flags & SHF_TLS) == 0 \ |
||
319 | && (segment)->p_type != PT_TLS \ |
||
320 | && (segment)->p_type != PT_PHDR)) \ |
||
321 | /* Any section besides one of type SHT_NOBITS must have file \ |
||
322 | offsets within the segment. */ \ |
||
323 | && ((sec_hdr)->sh_type == SHT_NOBITS \ |
||
324 | || ((bfd_vma) (sec_hdr)->sh_offset >= (segment)->p_offset \ |
||
325 | && (!(strict) \ |
||
326 | || ((sec_hdr)->sh_offset - (segment)->p_offset \ |
||
327 | <= (segment)->p_filesz - 1)) \ |
||
328 | && (((sec_hdr)->sh_offset - (segment)->p_offset \ |
||
329 | + ELF_SECTION_SIZE(sec_hdr, segment)) \ |
||
330 | <= (segment)->p_filesz))) \ |
||
331 | /* SHF_ALLOC sections must have VMAs within the segment. */ \ |
||
332 | && (!(check_vma) \ |
||
333 | || ((sec_hdr)->sh_flags & SHF_ALLOC) == 0 \ |
||
334 | || ((sec_hdr)->sh_addr >= (segment)->p_vaddr \ |
||
335 | && (!(strict) \ |
||
336 | || ((sec_hdr)->sh_addr - (segment)->p_vaddr \ |
||
337 | <= (segment)->p_memsz - 1)) \ |
||
338 | && (((sec_hdr)->sh_addr - (segment)->p_vaddr \ |
||
339 | + ELF_SECTION_SIZE(sec_hdr, segment)) \ |
||
340 | <= (segment)->p_memsz))) \ |
||
341 | /* No zero size sections at start or end of PT_DYNAMIC. */ \ |
||
342 | && ((segment)->p_type != PT_DYNAMIC \ |
||
343 | || (sec_hdr)->sh_size != 0 \ |
||
344 | || (segment)->p_memsz == 0 \ |
||
345 | || (((sec_hdr)->sh_type == SHT_NOBITS \ |
||
346 | || ((bfd_vma) (sec_hdr)->sh_offset > (segment)->p_offset \ |
||
347 | && ((sec_hdr)->sh_offset - (segment)->p_offset \ |
||
348 | < (segment)->p_filesz))) \ |
||
349 | && (((sec_hdr)->sh_flags & SHF_ALLOC) == 0 \ |
||
350 | || ((sec_hdr)->sh_addr > (segment)->p_vaddr \ |
||
351 | && ((sec_hdr)->sh_addr - (segment)->p_vaddr \ |
||
352 | < (segment)->p_memsz)))))) |
||
353 | |||
354 | #define ELF_SECTION_IN_SEGMENT(sec_hdr, segment) \ |
||
355 | (ELF_SECTION_IN_SEGMENT_1 (sec_hdr, segment, 1, 0)) |
||
356 | |||
357 | #define ELF_SECTION_IN_SEGMENT_STRICT(sec_hdr, segment) \ |
||
358 | (ELF_SECTION_IN_SEGMENT_1 (sec_hdr, segment, 1, 1)) |
||
359 | |||
360 | #endif /* _ELF_INTERNAL_H */>>=>=>=>=> |