1 /* Interface for libelf. 2 Copyright (C) 1998-2010 Red Hat, Inc. 3 This file is part of elfutils. 4 5 This file is free software; you can redistribute it and/or modify 6 it under the terms of either 7 8 * the GNU Lesser General Public License as published by the Free 9 Software Foundation; either version 3 of the License, or (at 10 your option) any later version 11 12 or 13 14 * the GNU General Public License as published by the Free 15 Software Foundation; either version 2 of the License, or (at 16 your option) any later version 17 18 or both in parallel, as here. 19 20 elfutils is distributed in the hope that it will be useful, but 21 WITHOUT ANY WARRANTY; without even the implied warranty of 22 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 23 General Public License for more details. 24 25 You should have received copies of the GNU General Public License and 26 the GNU Lesser General Public License along with this program. If 27 not, see <http://www.gnu.org/licenses/>. */ 28 29 #ifndef _LIBELF_H 30 #define _LIBELF_H 1 31 32 #include <sys/types.h> 33 34 /* Get the ELF types. */ 35 #include <elf.h> 36 37 38 /* Known translation types. */ 39 typedef enum 40 { 41 ELF_T_BYTE, /* unsigned char */ 42 ELF_T_ADDR, /* Elf32_Addr, Elf64_Addr, ... */ 43 ELF_T_DYN, /* Dynamic section record. */ 44 ELF_T_EHDR, /* ELF header. */ 45 ELF_T_HALF, /* Elf32_Half, Elf64_Half, ... */ 46 ELF_T_OFF, /* Elf32_Off, Elf64_Off, ... */ 47 ELF_T_PHDR, /* Program header. */ 48 ELF_T_RELA, /* Relocation entry with addend. */ 49 ELF_T_REL, /* Relocation entry. */ 50 ELF_T_SHDR, /* Section header. */ 51 ELF_T_SWORD, /* Elf32_Sword, Elf64_Sword, ... */ 52 ELF_T_SYM, /* Symbol record. */ 53 ELF_T_WORD, /* Elf32_Word, Elf64_Word, ... */ 54 ELF_T_XWORD, /* Elf32_Xword, Elf64_Xword, ... */ 55 ELF_T_SXWORD, /* Elf32_Sxword, Elf64_Sxword, ... */ 56 ELF_T_VDEF, /* Elf32_Verdef, Elf64_Verdef, ... */ 57 ELF_T_VDAUX, /* Elf32_Verdaux, Elf64_Verdaux, ... */ 58 ELF_T_VNEED, /* Elf32_Verneed, Elf64_Verneed, ... */ 59 ELF_T_VNAUX, /* Elf32_Vernaux, Elf64_Vernaux, ... */ 60 ELF_T_NHDR, /* Elf32_Nhdr, Elf64_Nhdr, ... */ 61 ELF_T_SYMINFO, /* Elf32_Syminfo, Elf64_Syminfo, ... */ 62 ELF_T_MOVE, /* Elf32_Move, Elf64_Move, ... */ 63 ELF_T_LIB, /* Elf32_Lib, Elf64_Lib, ... */ 64 ELF_T_GNUHASH, /* GNU-style hash section. */ 65 ELF_T_AUXV, /* Elf32_auxv_t, Elf64_auxv_t, ... */ 66 /* Keep this the last entry. */ 67 ELF_T_NUM 68 } Elf_Type; 69 70 /* Descriptor for data to be converted to or from memory format. */ 71 typedef struct 72 { 73 void *d_buf; /* Pointer to the actual data. */ 74 Elf_Type d_type; /* Type of this piece of data. */ 75 unsigned int d_version; /* ELF version. */ 76 size_t d_size; /* Size in bytes. */ 77 loff_t d_off; /* Offset into section. */ 78 size_t d_align; /* Alignment in section. */ 79 } Elf_Data; 80 81 82 /* Commands for `...'. */ 83 typedef enum 84 { 85 ELF_C_NULL, /* Nothing, terminate, or compute only. */ 86 ELF_C_READ, /* Read .. */ 87 ELF_C_RDWR, /* Read and write .. */ 88 ELF_C_WRITE, /* Write .. */ 89 ELF_C_CLR, /* Clear flag. */ 90 ELF_C_SET, /* Set flag. */ 91 ELF_C_FDDONE, /* Signal that file descriptor will not be 92 used anymore. */ 93 ELF_C_FDREAD, /* Read rest of data so that file descriptor 94 is not used anymore. */ 95 /* The following are extensions. */ 96 ELF_C_READ_MMAP, /* Read, but mmap the file if possible. */ 97 ELF_C_RDWR_MMAP, /* Read and write, with mmap. */ 98 ELF_C_WRITE_MMAP, /* Write, with mmap. */ 99 ELF_C_READ_MMAP_PRIVATE, /* Read, but memory is writable, results are 100 not written to the file. */ 101 ELF_C_EMPTY, /* Copy basic file data but not the content. */ 102 /* Keep this the last entry. */ 103 ELF_C_NUM 104 } Elf_Cmd; 105 106 107 /* Flags for the ELF structures. */ 108 enum 109 { 110 ELF_F_DIRTY = 0x1, 111 #define ELF_F_DIRTY ELF_F_DIRTY 112 ELF_F_LAYOUT = 0x4, 113 #define ELF_F_LAYOUT ELF_F_LAYOUT 114 ELF_F_PERMISSIVE = 0x8 115 #define ELF_F_PERMISSIVE ELF_F_PERMISSIVE 116 }; 117 118 119 /* Identification values for recognized object files. */ 120 typedef enum 121 { 122 ELF_K_NONE, /* Unknown. */ 123 ELF_K_AR, /* Archive. */ 124 ELF_K_COFF, /* Stupid old COFF. */ 125 ELF_K_ELF, /* ELF file. */ 126 /* Keep this the last entry. */ 127 ELF_K_NUM 128 } Elf_Kind; 129 130 131 /* Archive member header. */ 132 typedef struct 133 { 134 char *ar_name; /* Name of archive member. */ 135 time_t ar_date; /* File date. */ 136 uid_t ar_uid; /* User ID. */ 137 gid_t ar_gid; /* Group ID. */ 138 mode_t ar_mode; /* File mode. */ 139 loff_t ar_size; /* File size. */ 140 char *ar_rawname; /* Original name of archive member. */ 141 } Elf_Arhdr; 142 143 144 /* Archive symbol table entry. */ 145 typedef struct 146 { 147 char *as_name; /* Symbol name. */ 148 size_t as_off; /* Offset for this file in the archive. */ 149 unsigned long int as_hash; /* Hash value of the name. */ 150 } Elf_Arsym; 151 152 153 /* Descriptor for the ELF file. */ 154 typedef struct Elf Elf; 155 156 /* Descriptor for ELF file section. */ 157 typedef struct Elf_Scn Elf_Scn; 158 159 160 #ifdef __cplusplus 161 extern "C" { 162 #endif 163 164 /* Return descriptor for ELF file to work according to CMD. */ 165 extern Elf *elf_begin (int __fildes, Elf_Cmd __cmd, Elf *__ref); 166 167 /* Create a clone of an existing ELF descriptor. */ 168 extern Elf *elf_clone (Elf *__elf, Elf_Cmd __cmd); 169 170 /* Create descriptor for memory region. */ 171 extern Elf *elf_memory (char *__image, size_t __size); 172 173 /* Advance archive descriptor to next element. */ 174 extern Elf_Cmd elf_next (Elf *__elf); 175 176 /* Free resources allocated for ELF. */ 177 extern int elf_end (Elf *__elf); 178 179 /* Update ELF descriptor and write file to disk. */ 180 extern loff_t elf_update (Elf *__elf, Elf_Cmd __cmd); 181 182 /* Determine what kind of file is associated with ELF. */ 183 extern Elf_Kind elf_kind (Elf *__elf) __attribute__ ((__pure__)); 184 185 /* Get the base offset for an object file. */ 186 extern loff_t elf_getbase (Elf *__elf); 187 188 189 /* Retrieve file identification data. */ 190 extern char *elf_getident (Elf *__elf, size_t *__nbytes); 191 192 /* Retrieve class-dependent object file header. */ 193 extern Elf32_Ehdr *elf32_getehdr (Elf *__elf); 194 /* Similar but this time the binary calls is ELFCLASS64. */ 195 extern Elf64_Ehdr *elf64_getehdr (Elf *__elf); 196 197 /* Create ELF header if none exists. */ 198 extern Elf32_Ehdr *elf32_newehdr (Elf *__elf); 199 /* Similar but this time the binary calls is ELFCLASS64. */ 200 extern Elf64_Ehdr *elf64_newehdr (Elf *__elf); 201 202 /* Get the number of program headers in the ELF file. If the file uses 203 more headers than can be represented in the e_phnum field of the ELF 204 header the information from the sh_info field in the zeroth section 205 header is used. */ 206 extern int elf_getphdrnum (Elf *__elf, size_t *__dst); 207 208 /* Retrieve class-dependent program header table. */ 209 extern Elf32_Phdr *elf32_getphdr (Elf *__elf); 210 /* Similar but this time the binary calls is ELFCLASS64. */ 211 extern Elf64_Phdr *elf64_getphdr (Elf *__elf); 212 213 /* Create ELF program header. */ 214 extern Elf32_Phdr *elf32_newphdr (Elf *__elf, size_t __cnt); 215 /* Similar but this time the binary calls is ELFCLASS64. */ 216 extern Elf64_Phdr *elf64_newphdr (Elf *__elf, size_t __cnt); 217 218 219 /* Get section at INDEX. */ 220 extern Elf_Scn *elf_getscn (Elf *__elf, size_t __index); 221 222 /* Get section at OFFSET. */ 223 extern Elf_Scn *elf32_offscn (Elf *__elf, Elf32_Off __offset); 224 /* Similar bug this time the binary calls is ELFCLASS64. */ 225 extern Elf_Scn *elf64_offscn (Elf *__elf, Elf64_Off __offset); 226 227 /* Get index of section. */ 228 extern size_t elf_ndxscn (Elf_Scn *__scn); 229 230 /* Get section with next section index. */ 231 extern Elf_Scn *elf_nextscn (Elf *__elf, Elf_Scn *__scn); 232 233 /* Create a new section and append it at the end of the table. */ 234 extern Elf_Scn *elf_newscn (Elf *__elf); 235 236 /* Get the section index of the extended section index table for the 237 given symbol table. */ 238 extern int elf_scnshndx (Elf_Scn *__scn); 239 240 /* Get the number of sections in the ELF file. If the file uses more 241 sections than can be represented in the e_shnum field of the ELF 242 header the information from the sh_size field in the zeroth section 243 header is used. */ 244 extern int elf_getshdrnum (Elf *__elf, size_t *__dst); 245 /* Sun messed up the implementation of 'elf_getshnum' in their implementation. 246 It was agreed to make the same functionality available under a different 247 name and obsolete the old name. */ 248 extern int elf_getshnum (Elf *__elf, size_t *__dst) 249 __attribute__ ((__deprecated__)); 250 251 252 /* Get the section index of the section header string table in the ELF 253 file. If the index cannot be represented in the e_shnum field of 254 the ELF header the information from the sh_link field in the zeroth 255 section header is used. */ 256 extern int elf_getshdrstrndx (Elf *__elf, size_t *__dst); 257 /* Sun messed up the implementation of 'elf_getshnum' in their implementation. 258 It was agreed to make the same functionality available under a different 259 name and obsolete the old name. */ 260 extern int elf_getshstrndx (Elf *__elf, size_t *__dst) 261 __attribute__ ((__deprecated__)); 262 263 264 /* Retrieve section header of ELFCLASS32 binary. */ 265 extern Elf32_Shdr *elf32_getshdr (Elf_Scn *__scn); 266 /* Similar for ELFCLASS64. */ 267 extern Elf64_Shdr *elf64_getshdr (Elf_Scn *__scn); 268 269 270 /* Set or clear flags for ELF file. */ 271 extern unsigned int elf_flagelf (Elf *__elf, Elf_Cmd __cmd, 272 unsigned int __flags); 273 /* Similarly for the ELF header. */ 274 extern unsigned int elf_flagehdr (Elf *__elf, Elf_Cmd __cmd, 275 unsigned int __flags); 276 /* Similarly for the ELF program header. */ 277 extern unsigned int elf_flagphdr (Elf *__elf, Elf_Cmd __cmd, 278 unsigned int __flags); 279 /* Similarly for the given ELF section. */ 280 extern unsigned int elf_flagscn (Elf_Scn *__scn, Elf_Cmd __cmd, 281 unsigned int __flags); 282 /* Similarly for the given ELF data. */ 283 extern unsigned int elf_flagdata (Elf_Data *__data, Elf_Cmd __cmd, 284 unsigned int __flags); 285 /* Similarly for the given ELF section header. */ 286 extern unsigned int elf_flagshdr (Elf_Scn *__scn, Elf_Cmd __cmd, 287 unsigned int __flags); 288 289 290 /* Get data from section while translating from file representation 291 to memory representation. */ 292 extern Elf_Data *elf_getdata (Elf_Scn *__scn, Elf_Data *__data); 293 294 /* Get uninterpreted section content. */ 295 extern Elf_Data *elf_rawdata (Elf_Scn *__scn, Elf_Data *__data); 296 297 /* Create new data descriptor for section SCN. */ 298 extern Elf_Data *elf_newdata (Elf_Scn *__scn); 299 300 /* Get data translated from a chunk of the file contents as section data 301 would be for TYPE. The resulting Elf_Data pointer is valid until 302 elf_end (ELF) is called. */ 303 extern Elf_Data *elf_getdata_rawchunk (Elf *__elf, 304 loff_t __offset, size_t __size, 305 Elf_Type __type); 306 307 308 /* Return pointer to string at OFFSET in section INDEX. */ 309 extern char *elf_strptr (Elf *__elf, size_t __index, size_t __offset); 310 311 312 /* Return header of archive. */ 313 extern Elf_Arhdr *elf_getarhdr (Elf *__elf); 314 315 /* Return offset in archive for current file ELF. */ 316 extern loff_t elf_getaroff (Elf *__elf); 317 318 /* Select archive element at OFFSET. */ 319 extern size_t elf_rand (Elf *__elf, size_t __offset); 320 321 /* Get symbol table of archive. */ 322 extern Elf_Arsym *elf_getarsym (Elf *__elf, size_t *__narsyms); 323 324 325 /* Control ELF descriptor. */ 326 extern int elf_cntl (Elf *__elf, Elf_Cmd __cmd); 327 328 /* Retrieve uninterpreted file contents. */ 329 extern char *elf_rawfile (Elf *__elf, size_t *__nbytes); 330 331 332 /* Return size of array of COUNT elements of the type denoted by TYPE 333 in the external representation. The binary class is taken from ELF. 334 The result is based on version VERSION of the ELF standard. */ 335 extern size_t elf32_fsize (Elf_Type __type, size_t __count, 336 unsigned int __version) 337 __attribute__ ((__const__)); 338 /* Similar but this time the binary calls is ELFCLASS64. */ 339 extern size_t elf64_fsize (Elf_Type __type, size_t __count, 340 unsigned int __version) 341 __attribute__ ((__const__)); 342 343 344 /* Convert data structure from the representation in the file represented 345 by ELF to their memory representation. */ 346 extern Elf_Data *elf32_xlatetom (Elf_Data *__dest, const Elf_Data *__src, 347 unsigned int __encode); 348 /* Same for 64 bit class. */ 349 extern Elf_Data *elf64_xlatetom (Elf_Data *__dest, const Elf_Data *__src, 350 unsigned int __encode); 351 352 /* Convert data structure from to the representation in memory 353 represented by ELF file representation. */ 354 extern Elf_Data *elf32_xlatetof (Elf_Data *__dest, const Elf_Data *__src, 355 unsigned int __encode); 356 /* Same for 64 bit class. */ 357 extern Elf_Data *elf64_xlatetof (Elf_Data *__dest, const Elf_Data *__src, 358 unsigned int __encode); 359 360 361 /* Return error code of last failing function call. This value is kept 362 separately for each thread. */ 363 extern int elf_errno (void); 364 365 /* Return error string for ERROR. If ERROR is zero, return error string 366 for most recent error or NULL is none occurred. If ERROR is -1 the 367 behaviour is similar to the last case except that not NULL but a legal 368 string is returned. */ 369 extern const char *elf_errmsg (int __error); 370 371 372 /* Coordinate ELF library and application versions. */ 373 extern unsigned int elf_version (unsigned int __version); 374 375 /* Set fill bytes used to fill holes in data structures. */ 376 extern void elf_fill (int __fill); 377 378 /* Compute hash value. */ 379 extern unsigned long int elf_hash (const char *__string) 380 __attribute__ ((__pure__)); 381 382 /* Compute hash value using the GNU-specific hash function. */ 383 extern unsigned long int elf_gnu_hash (const char *__string) 384 __attribute__ ((__pure__)); 385 386 387 /* Compute simple checksum from permanent parts of the ELF file. */ 388 extern long int elf32_checksum (Elf *__elf); 389 /* Similar but this time the binary calls is ELFCLASS64. */ 390 extern long int elf64_checksum (Elf *__elf); 391 392 #ifdef __cplusplus 393 } 394 #endif 395 396 #endif /* libelf.h */ 397