1 /* 2 * Copyright (c) 2006-2024 RT-Thread Development Team 3 * 4 * SPDX-License-Identifier: Apache-2.0 5 * 6 * Change Logs: 7 * Date Author Notes 8 * 2018/08/29 Bernard first version 9 * 2021/04/23 chunyexixiaoyu distinguish 32-bit and 64-bit 10 */ 11 12 #ifndef DL_ELF_H__ 13 #define DL_ELF_H__ 14 15 typedef rt_uint8_t Elf_Byte; 16 17 typedef rt_uint32_t Elf32_Addr; /* Unsigned program address */ 18 typedef rt_uint32_t Elf32_Off; /* Unsigned file offset */ 19 typedef rt_int32_t Elf32_Sword; /* Signed large integer */ 20 typedef rt_uint32_t Elf32_Word; /* Unsigned large integer */ 21 typedef rt_uint16_t Elf32_Half; /* Unsigned medium integer */ 22 23 typedef rt_uint64_t Elf64_Addr; 24 typedef rt_uint16_t Elf64_Half; 25 typedef rt_int16_t Elf64_SHalf; 26 typedef rt_uint64_t Elf64_Off; 27 typedef rt_int32_t Elf64_Sword; 28 typedef rt_uint32_t Elf64_Word; 29 typedef rt_uint64_t Elf64_Xword; 30 typedef rt_int64_t Elf64_Sxword; 31 typedef rt_uint16_t Elf64_Section; 32 33 /* e_ident[] magic number */ 34 #define ELFMAG0 0x7f /* e_ident[EI_MAG0] */ 35 #define ELFMAG1 'E' /* e_ident[EI_MAG1] */ 36 #define ELFMAG2 'L' /* e_ident[EI_MAG2] */ 37 #define ELFMAG3 'F' /* e_ident[EI_MAG3] */ 38 #define RTMMAG "\177RTM" /* magic */ 39 #define ELFMAG "\177ELF" /* magic */ 40 #define SELFMAG 4 /* size of magic */ 41 42 #define EI_CLASS 4 /* file class */ 43 #define EI_NIDENT 16 /* Size of e_ident[] */ 44 45 /* e_ident[] file class */ 46 #define ELFCLASSNONE 0 /* invalid */ 47 #define ELFCLASS32 1 /* 32-bit objs */ 48 #define ELFCLASS64 2 /* 64-bit objs */ 49 #define ELFCLASSNUM 3 /* number of classes */ 50 51 /* e_ident[] data encoding */ 52 #define ELFDATANONE 0 /* invalid */ 53 #define ELFDATA2LSB 1 /* Little-Endian */ 54 #define ELFDATA2MSB 2 /* Big-Endian */ 55 #define ELFDATANUM 3 /* number of data encode defines */ 56 57 /* e_ident */ 58 #define IS_ELF(ehdr) ((ehdr).e_ident[EI_MAG0] == ELFMAG0 && \ 59 (ehdr).e_ident[EI_MAG1] == ELFMAG1 && \ 60 (ehdr).e_ident[EI_MAG2] == ELFMAG2 && \ 61 (ehdr).e_ident[EI_MAG3] == ELFMAG3) 62 63 #define ET_NONE 0 /* No file type */ 64 #define ET_REL 1 /* Relocatable file */ 65 #define ET_EXEC 2 /* Executable file */ 66 #define ET_DYN 3 /* Shared object file */ 67 #define ET_CORE 4 /* Core file */ 68 69 /* ELF Header */ 70 typedef struct elfhdr 71 { 72 unsigned char e_ident[EI_NIDENT]; /* ELF Identification */ 73 Elf32_Half e_type; /* object file type */ 74 Elf32_Half e_machine; /* machine */ 75 Elf32_Word e_version; /* object file version */ 76 Elf32_Addr e_entry; /* virtual entry point */ 77 Elf32_Off e_phoff; /* program header table offset */ 78 Elf32_Off e_shoff; /* section header table offset */ 79 Elf32_Word e_flags; /* processor-specific flags */ 80 Elf32_Half e_ehsize; /* ELF header size */ 81 Elf32_Half e_phentsize; /* program header entry size */ 82 Elf32_Half e_phnum; /* number of program header entries */ 83 Elf32_Half e_shentsize; /* section header entry size */ 84 Elf32_Half e_shnum; /* number of section header entries */ 85 Elf32_Half e_shstrndx; /* section header table's "section 86 header string table" entry offset */ 87 } Elf32_Ehdr; 88 89 typedef struct elf64_hdr 90 { 91 unsigned char e_ident[EI_NIDENT]; /* ELF Identification */ 92 Elf64_Half e_type; /* object file type */ 93 Elf64_Half e_machine; /* machine */ 94 Elf64_Word e_version; /* object file version */ 95 Elf64_Addr e_entry; /* virtual entry point */ 96 Elf64_Off e_phoff; /* program header table offset */ 97 Elf64_Off e_shoff; /* section header table offset */ 98 Elf64_Word e_flags; /* processor-specific flags */ 99 Elf64_Half e_ehsize; /* ELF header size */ 100 Elf64_Half e_phentsize; /* program header entry size */ 101 Elf64_Half e_phnum; /* number of program header entries */ 102 Elf64_Half e_shentsize; /* section header entry size */ 103 Elf64_Half e_shnum; /* number of section header entries */ 104 Elf64_Half e_shstrndx; /* section header table's "section 105 header string table" entry offset */ 106 } Elf64_Ehdr; 107 108 /* Section Header */ 109 typedef struct 110 { 111 Elf32_Word sh_name; /* name - index into section header 112 string table section */ 113 Elf32_Word sh_type; /* type */ 114 Elf32_Word sh_flags; /* flags */ 115 Elf32_Addr sh_addr; /* address */ 116 Elf32_Off sh_offset; /* file offset */ 117 Elf32_Word sh_size; /* section size */ 118 Elf32_Word sh_link; /* section header table index link */ 119 Elf32_Word sh_info; /* extra information */ 120 Elf32_Word sh_addralign; /* address alignment */ 121 Elf32_Word sh_entsize; /* section entry size */ 122 } Elf32_Shdr; 123 124 typedef struct 125 { 126 Elf64_Word sh_name; /* Section name (string tbl index) */ 127 Elf64_Word sh_type; /* Section type */ 128 Elf64_Xword sh_flags; /* Section flags */ 129 Elf64_Addr sh_addr; /* Section virtual addr at execution */ 130 Elf64_Off sh_offset; /* Section file offset */ 131 Elf64_Xword sh_size; /* Section size in bytes */ 132 Elf64_Word sh_link; /* Link to another section */ 133 Elf64_Word sh_info; /* Additional section information */ 134 Elf64_Xword sh_addralign; /* Section alignment */ 135 Elf64_Xword sh_entsize; /* Entry size if section holds table */ 136 } Elf64_Shdr; 137 138 /* Section names */ 139 #define ELF_BSS ".bss" /* uninitialized data */ 140 #define ELF_DATA ".data" /* initialized data */ 141 #define ELF_DEBUG ".debug" /* debug */ 142 #define ELF_DYNAMIC ".dynamic" /* dynamic linking information */ 143 #define ELF_DYNSTR ".dynstr" /* dynamic string table */ 144 #define ELF_DYNSYM ".dynsym" /* dynamic symbol table */ 145 #define ELF_FINI ".fini" /* termination code */ 146 #define ELF_GOT ".got" /* global offset table */ 147 #define ELF_HASH ".hash" /* symbol hash table */ 148 #define ELF_INIT ".init" /* initialization code */ 149 #define ELF_REL_DATA ".rel.data" /* relocation data */ 150 #define ELF_REL_FINI ".rel.fini" /* relocation termination code */ 151 #define ELF_REL_INIT ".rel.init" /* relocation initialization code */ 152 #define ELF_REL_DYN ".rel.dyn" /* relocaltion dynamic link info */ 153 #define ELF_REL_RODATA ".rel.rodata" /* relocation read-only data */ 154 #define ELF_REL_TEXT ".rel.text" /* relocation code */ 155 #define ELF_RODATA ".rodata" /* read-only data */ 156 #define ELF_SHSTRTAB ".shstrtab" /* section header string table */ 157 #define ELF_STRTAB ".strtab" /* string table */ 158 #define ELF_SYMTAB ".symtab" /* symbol table */ 159 #define ELF_TEXT ".text" /* code */ 160 #define ELF_RTMSYMTAB "RTMSymTab" 161 162 /* Symbol Table Entry */ 163 typedef struct elf32_sym 164 { 165 Elf32_Word st_name; /* name - index into string table */ 166 Elf32_Addr st_value; /* symbol value */ 167 Elf32_Word st_size; /* symbol size */ 168 unsigned char st_info; /* type and binding */ 169 unsigned char st_other; /* 0 - no defined meaning */ 170 Elf32_Half st_shndx; /* section header index */ 171 } Elf32_Sym; 172 173 typedef struct 174 { 175 Elf64_Word st_name; /* Symbol name (string tbl index) */ 176 unsigned char st_info; /* Symbol type and binding */ 177 unsigned char st_other; /* Symbol visibility */ 178 Elf64_Section st_shndx; /* Section index */ 179 Elf64_Addr st_value; /* Symbol value */ 180 Elf64_Xword st_size; /* Symbol size */ 181 } Elf64_Sym; 182 183 #define STB_LOCAL 0 /* BIND */ 184 #define STB_GLOBAL 1 185 #define STB_WEAK 2 186 #define STB_NUM 3 187 188 #define STB_LOPROC 13 /* processor specific range */ 189 #define STB_HIPROC 15 190 191 #define STT_NOTYPE 0 /* symbol type is unspecified */ 192 #define STT_OBJECT 1 /* data object */ 193 #define STT_FUNC 2 /* code object */ 194 #define STT_SECTION 3 /* symbol identifies an ELF section */ 195 #define STT_FILE 4 /* symbol's name is file name */ 196 #define STT_COMMON 5 /* common data object */ 197 #define STT_TLS 6 /* thread-local data object */ 198 #define STT_NUM 7 /* # defined types in generic range */ 199 #define STT_LOOS 10 /* OS specific range */ 200 #define STT_HIOS 12 201 #define STT_LOPROC 13 /* processor specific range */ 202 #define STT_HIPROC 15 203 204 #define STN_UNDEF 0 /* undefined */ 205 206 #define ELF_ST_BIND(info) ((info) >> 4) 207 #define ELF_ST_TYPE(info) ((info) & 0xf) 208 #define ELF_ST_INFO(bind, type) (((bind)<<4)+((type)&0xf)) 209 210 /* Relocation entry with implicit addend */ 211 typedef struct 212 { 213 Elf32_Addr r_offset; /* offset of relocation */ 214 Elf32_Word r_info; /* symbol table index and type */ 215 } Elf32_Rel; 216 217 typedef struct 218 { 219 Elf64_Addr r_offset; /* Address */ 220 Elf64_Xword r_info; /* Relocation type and symbol index */ 221 } Elf64_Rel; 222 223 /* Relocation entry with explicit addend */ 224 typedef struct 225 { 226 Elf32_Addr r_offset; /* offset of relocation */ 227 Elf32_Word r_info; /* symbol table index and type */ 228 Elf32_Sword r_addend; 229 } Elf32_Rela; 230 231 typedef struct 232 { 233 Elf64_Addr r_offset; /* Address */ 234 Elf64_Xword r_info; /* Relocation type and symbol index */ 235 Elf64_Sxword r_addend; /* Addend */ 236 } Elf64_Rela; 237 238 /* Extract relocation info - r_info */ 239 #define ELF32_R_SYM(i) ((i) >> 8) 240 #define ELF32_R_TYPE(i) ((unsigned char) (i)) 241 #define ELF32_R_INFO(s,t) (((s) << 8) + (unsigned char)(t)) 242 243 #define ELF64_R_SYM(i) ((i) >> 32) 244 #define ELF64_R_TYPE(i) ((i) & 0xffffffff) 245 #define ELF64_R_INFO(sym,type) ((((Elf64_Xword) (sym)) << 32) + (type)) 246 247 /* 248 * Relocation type for arm 249 */ 250 #define R_ARM_NONE 0 251 #define R_ARM_PC24 1 252 #define R_ARM_ABS32 2 253 #define R_ARM_REL32 3 254 #define R_ARM_THM_CALL 10 255 #define R_ARM_GLOB_DAT 21 256 #define R_ARM_JUMP_SLOT 22 257 #define R_ARM_RELATIVE 23 258 #define R_ARM_GOT_BREL 26 259 #define R_ARM_PLT32 27 260 #define R_ARM_CALL 28 261 #define R_ARM_JUMP24 29 262 #define R_ARM_THM_JUMP24 30 263 #define R_ARM_V4BX 40 264 265 /* 266 * Relocation type for x86 267 */ 268 #define R_386_NONE 0 269 #define R_386_32 1 270 #define R_386_PC32 2 271 #define R_386_GOT32 3 272 #define R_386_PLT32 4 273 #define R_386_COPY 5 274 #define R_386_GLOB_DAT 6 275 #define R_386_JMP_SLOT 7 276 #define R_386_RELATIVE 8 277 #define R_386_GOTOFF 9 278 #define R_386_GOTPC 10 279 280 /* Program Header */ 281 typedef struct 282 { 283 Elf32_Word p_type; /* segment type */ 284 Elf32_Off p_offset; /* segment offset */ 285 Elf32_Addr p_vaddr; /* virtual address of segment */ 286 Elf32_Addr p_paddr; /* physical address - ignored? */ 287 Elf32_Word p_filesz; /* number of bytes in file for seg. */ 288 Elf32_Word p_memsz; /* number of bytes in mem. for seg. */ 289 Elf32_Word p_flags; /* flags */ 290 Elf32_Word p_align; /* memory alignment */ 291 } Elf32_Phdr; 292 293 typedef struct 294 { 295 Elf64_Word p_type; /* Segment type */ 296 Elf64_Word p_flags; /* Segment flags */ 297 Elf64_Off p_offset; /* Segment file offset */ 298 Elf64_Addr p_vaddr; /* Segment virtual address */ 299 Elf64_Addr p_paddr; /* Segment physical address */ 300 Elf64_Xword p_filesz; /* Segment size in file */ 301 Elf64_Xword p_memsz; /* Segment size in memory */ 302 Elf64_Xword p_align; /* Segment alignment */ 303 } Elf64_Phdr; 304 305 /* p_type */ 306 #define PT_NULL 0 307 #define PT_LOAD 1 308 #define PT_DYNAMIC 2 309 #define PT_INTERP 3 310 #define PT_NOTE 4 311 #define PT_SHLIB 5 312 #define PT_PHDR 6 313 #define PT_TLS 7 314 #define PT_NUM 8 315 #define PT_LOOS 0x60000000 316 #define PT_HIOS 0x6fffffff 317 #define PT_LOPROC 0x70000000 318 #define PT_HIPROC 0x7fffffff 319 320 /* p_flags */ 321 #define PF_X 1 322 #define PF_W 2 323 #define PF_R 4 324 325 /* sh_type */ 326 #define SHT_NULL 0 /* inactive */ 327 #define SHT_PROGBITS 1 /* program defined information */ 328 #define SHT_SYMTAB 2 /* symbol table section */ 329 #define SHT_STRTAB 3 /* string table section */ 330 #define SHT_RELA 4 /* relocation section with addends*/ 331 #define SHT_HASH 5 /* symbol hash table section */ 332 #define SHT_DYNAMIC 6 /* dynamic section */ 333 #define SHT_NOTE 7 /* note section */ 334 #define SHT_NOBITS 8 /* no space section */ 335 #define SHT_REL 9 /* relocation section without addends */ 336 #define SHT_SHLIB 10 /* reserved - purpose unknown */ 337 #define SHT_DYNSYM 11 /* dynamic symbol table section */ 338 #define SHT_NUM 12 /* number of section types */ 339 #define SHT_LOPROC 0x70000000 /* reserved range for processor */ 340 #define SHT_HIPROC 0x7fffffff /* specific section header types */ 341 #define SHT_LOUSER 0x80000000 /* reserved range for application */ 342 #define SHT_HIUSER 0xffffffff /* specific indexes */ 343 344 /* Section Attribute Flags - sh_flags */ 345 #define SHF_WRITE 0x1 /* Writable */ 346 #define SHF_ALLOC 0x2 /* occupies memory */ 347 #define SHF_EXECINSTR 0x4 /* executable */ 348 #define SHF_MASKPROC 0xf0000000 /* reserved bits for processor */ 349 /* specific section attributes */ 350 351 #define IS_PROG(s) (s.sh_type == SHT_PROGBITS) 352 #define IS_NOPROG(s) (s.sh_type == SHT_NOBITS) 353 #define IS_REL(s) (s.sh_type == SHT_REL) 354 #define IS_RELA(s) (s.sh_type == SHT_RELA) 355 #define IS_ALLOC(s) (s.sh_flags == SHF_ALLOC) 356 #define IS_AX(s) ((s.sh_flags & SHF_ALLOC) && (s.sh_flags & SHF_EXECINSTR)) 357 #define IS_AW(s) ((s.sh_flags & SHF_ALLOC) && (s.sh_flags & SHF_WRITE)) 358 359 #if (defined(__arm__) || defined(__i386__) || (__riscv_xlen == 32)) 360 #define elf_module ((Elf32_Ehdr *)module_ptr) 361 #define shdr ((Elf32_Shdr *)((rt_uint8_t *)module_ptr + elf_module->e_shoff)) 362 #define phdr ((Elf32_Phdr *)((rt_uint8_t *)module_ptr + elf_module->e_phoff)) 363 364 typedef Elf32_Sym Elf_Sym; 365 typedef Elf32_Rel Elf_Rel; 366 typedef Elf32_Addr Elf_Addr; 367 #elif (defined(__aarch64__) || defined(__x86_64__) || (__riscv_xlen == 64)) 368 #define elf_module ((Elf64_Ehdr *)module_ptr) 369 #define shdr ((Elf64_Shdr *)((rt_uint8_t *)module_ptr + elf_module->e_shoff)) 370 #define phdr ((Elf64_Phdr *)((rt_uint8_t *)module_ptr + elf_module->e_phoff)) 371 372 typedef Elf64_Sym Elf_Sym; 373 typedef Elf64_Rela Elf_Rel; 374 typedef Elf64_Addr Elf_Addr; 375 #endif 376 377 int dlmodule_relocate(struct rt_dlmodule *module, Elf_Rel *rel, Elf_Addr sym_val); 378 rt_err_t dlmodule_load_shared_object(struct rt_dlmodule *module, void *module_ptr); 379 rt_err_t dlmodule_load_relocated_object(struct rt_dlmodule *module, void *module_ptr); 380 381 #endif 382