1 /* $NetBSD: loadfile_elf32.c,v 1.24 2008/09/25 20:59:38 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 1997, 2008 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility, 9 * NASA Ames Research Center and by Christos Zoulas. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 23 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 30 * POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 /* If not included by exec_elf64.c, ELFSIZE won't be defined. */ 34 #ifndef ELFSIZE 35 #define ELFSIZE 32 36 #endif 37 38 #ifdef _STANDALONE 39 #include <lib/libsa/stand.h> 40 #include <lib/libkern/libkern.h> 41 #else 42 #include <stdio.h> 43 #include <string.h> 44 #include <errno.h> 45 #include <stdlib.h> 46 #include <unistd.h> 47 #include <fcntl.h> 48 #include <err.h> 49 #endif 50 51 #include <sys/param.h> 52 #include <sys/exec.h> 53 54 #include "loadfile.h" 55 56 #if ((ELFSIZE == 32) && defined(BOOT_ELF32)) || \ 57 ((ELFSIZE == 64) && defined(BOOT_ELF64)) 58 59 #define ELFROUND (ELFSIZE / 8) 60 61 #ifndef _STANDALONE 62 #include "byteorder.h" 63 64 /* 65 * Byte swapping may be necessary in the non-_STANDLONE case because 66 * we may be built with a host compiler. 67 */ 68 #define E16(f) \ 69 f = (bo == ELFDATA2LSB) ? sa_htole16(f) : sa_htobe16(f) 70 #define E32(f) \ 71 f = (bo == ELFDATA2LSB) ? sa_htole32(f) : sa_htobe32(f) 72 #define E64(f) \ 73 f = (bo == ELFDATA2LSB) ? sa_htole64(f) : sa_htobe64(f) 74 75 #define I16(f) \ 76 f = (bo == ELFDATA2LSB) ? sa_le16toh(f) : sa_be16toh(f) 77 #define I32(f) \ 78 f = (bo == ELFDATA2LSB) ? sa_le32toh(f) : sa_be32toh(f) 79 #define I64(f) \ 80 f = (bo == ELFDATA2LSB) ? sa_le64toh(f) : sa_be64toh(f) 81 82 static void 83 internalize_ehdr(Elf_Byte bo, Elf_Ehdr *ehdr) 84 { 85 86 #if ELFSIZE == 32 87 I16(ehdr->e_type); 88 I16(ehdr->e_machine); 89 I32(ehdr->e_version); 90 I32(ehdr->e_entry); 91 I32(ehdr->e_phoff); 92 I32(ehdr->e_shoff); 93 I32(ehdr->e_flags); 94 I16(ehdr->e_ehsize); 95 I16(ehdr->e_phentsize); 96 I16(ehdr->e_phnum); 97 I16(ehdr->e_shentsize); 98 I16(ehdr->e_shnum); 99 I16(ehdr->e_shstrndx); 100 #elif ELFSIZE == 64 101 I16(ehdr->e_type); 102 I16(ehdr->e_machine); 103 I32(ehdr->e_version); 104 I64(ehdr->e_entry); 105 I64(ehdr->e_phoff); 106 I64(ehdr->e_shoff); 107 I32(ehdr->e_flags); 108 I16(ehdr->e_ehsize); 109 I16(ehdr->e_phentsize); 110 I16(ehdr->e_phnum); 111 I16(ehdr->e_shentsize); 112 I16(ehdr->e_shnum); 113 I16(ehdr->e_shstrndx); 114 #else 115 #error ELFSIZE is not 32 or 64 116 #endif 117 } 118 119 static void 120 externalize_ehdr(Elf_Byte bo, Elf_Ehdr *ehdr) 121 { 122 123 #if ELFSIZE == 32 124 E16(ehdr->e_type); 125 E16(ehdr->e_machine); 126 E32(ehdr->e_version); 127 E32(ehdr->e_entry); 128 E32(ehdr->e_phoff); 129 E32(ehdr->e_shoff); 130 E32(ehdr->e_flags); 131 E16(ehdr->e_ehsize); 132 E16(ehdr->e_phentsize); 133 E16(ehdr->e_phnum); 134 E16(ehdr->e_shentsize); 135 E16(ehdr->e_shnum); 136 E16(ehdr->e_shstrndx); 137 #elif ELFSIZE == 64 138 E16(ehdr->e_type); 139 E16(ehdr->e_machine); 140 E32(ehdr->e_version); 141 E64(ehdr->e_entry); 142 E64(ehdr->e_phoff); 143 E64(ehdr->e_shoff); 144 E32(ehdr->e_flags); 145 E16(ehdr->e_ehsize); 146 E16(ehdr->e_phentsize); 147 E16(ehdr->e_phnum); 148 E16(ehdr->e_shentsize); 149 E16(ehdr->e_shnum); 150 E16(ehdr->e_shstrndx); 151 #else 152 #error ELFSIZE is not 32 or 64 153 #endif 154 } 155 156 static void 157 internalize_phdr(Elf_Byte bo, Elf_Phdr *phdr) 158 { 159 160 #if ELFSIZE == 32 161 I32(phdr->p_type); 162 I32(phdr->p_offset); 163 I32(phdr->p_vaddr); 164 I32(phdr->p_paddr); 165 I32(phdr->p_filesz); 166 I32(phdr->p_memsz); 167 I32(phdr->p_flags); 168 I32(phdr->p_align); 169 #elif ELFSIZE == 64 170 I32(phdr->p_type); 171 I32(phdr->p_offset); 172 I64(phdr->p_vaddr); 173 I64(phdr->p_paddr); 174 I64(phdr->p_filesz); 175 I64(phdr->p_memsz); 176 I64(phdr->p_flags); 177 I64(phdr->p_align); 178 #else 179 #error ELFSIZE is not 32 or 64 180 #endif 181 } 182 183 static void 184 internalize_shdr(Elf_Byte bo, Elf_Shdr *shdr) 185 { 186 187 #if ELFSIZE == 32 188 I32(shdr->sh_name); 189 I32(shdr->sh_type); 190 I32(shdr->sh_flags); 191 I32(shdr->sh_addr); 192 I32(shdr->sh_offset); 193 I32(shdr->sh_size); 194 I32(shdr->sh_link); 195 I32(shdr->sh_info); 196 I32(shdr->sh_addralign); 197 I32(shdr->sh_entsize); 198 #elif ELFSIZE == 64 199 I32(shdr->sh_name); 200 I32(shdr->sh_type); 201 I64(shdr->sh_flags); 202 I64(shdr->sh_addr); 203 I64(shdr->sh_offset); 204 I64(shdr->sh_size); 205 I32(shdr->sh_link); 206 I32(shdr->sh_info); 207 I64(shdr->sh_addralign); 208 I64(shdr->sh_entsize); 209 #else 210 #error ELFSIZE is not 32 or 64 211 #endif 212 } 213 214 static void 215 externalize_shdr(Elf_Byte bo, Elf_Shdr *shdr) 216 { 217 218 #if ELFSIZE == 32 219 E32(shdr->sh_name); 220 E32(shdr->sh_type); 221 E32(shdr->sh_flags); 222 E32(shdr->sh_addr); 223 E32(shdr->sh_offset); 224 E32(shdr->sh_size); 225 E32(shdr->sh_link); 226 E32(shdr->sh_info); 227 E32(shdr->sh_addralign); 228 E32(shdr->sh_entsize); 229 #elif ELFSIZE == 64 230 E32(shdr->sh_name); 231 E32(shdr->sh_type); 232 E64(shdr->sh_flags); 233 E64(shdr->sh_addr); 234 E64(shdr->sh_offset); 235 E64(shdr->sh_size); 236 E32(shdr->sh_link); 237 E32(shdr->sh_info); 238 E64(shdr->sh_addralign); 239 E64(shdr->sh_entsize); 240 #else 241 #error ELFSIZE is not 32 or 64 242 #endif 243 } 244 #else /* _STANDALONE */ 245 /* 246 * Byte swapping is never necessary in the _STANDALONE case because 247 * we are being built with the target compiler. 248 */ 249 #define internalize_ehdr(bo, ehdr) /* nothing */ 250 #define externalize_ehdr(bo, ehdr) /* nothing */ 251 252 #define internalize_phdr(bo, phdr) /* nothing */ 253 254 #define internalize_shdr(bo, shdr) /* nothing */ 255 #define externalize_shdr(bo, shdr) /* nothing */ 256 #endif /* _STANDALONE */ 257 258 int 259 ELFNAMEEND(loadfile)(int fd, Elf_Ehdr *elf, u_long *marks, int flags) 260 { 261 Elf_Shdr *shp; 262 Elf_Phdr *phdr; 263 int i, j; 264 ssize_t sz; 265 int first; 266 paddr_t minp = ~0, maxp = 0, pos = 0; 267 paddr_t offset = marks[MARK_START], shpp, elfp = 0; 268 ssize_t nr; 269 struct __packed { 270 Elf_Nhdr nh; 271 uint8_t name[ELF_NOTE_NETBSD_NAMESZ + 1]; 272 uint8_t desc[ELF_NOTE_NETBSD_DESCSZ]; 273 } note; 274 275 /* some ports dont use the offset */ 276 offset = offset; 277 278 internalize_ehdr(elf->e_ident[EI_DATA], elf); 279 280 sz = elf->e_phnum * sizeof(Elf_Phdr); 281 phdr = ALLOC(sz); 282 283 if (lseek(fd, elf->e_phoff, SEEK_SET) == -1) { 284 WARN(("lseek phdr")); 285 goto freephdr; 286 } 287 nr = read(fd, phdr, sz); 288 if (nr == -1) { 289 WARN(("read program headers")); 290 goto freephdr; 291 } 292 if (nr != sz) { 293 errno = EIO; 294 WARN(("read program headers")); 295 goto freephdr; 296 } 297 298 for (first = 1, i = 0; i < elf->e_phnum; i++) { 299 internalize_phdr(elf->e_ident[EI_DATA], &phdr[i]); 300 301 #ifndef MD_LOADSEG /* Allow processor ABI specific segment loads */ 302 #define MD_LOADSEG(a) /*CONSTCOND*/0 303 #endif 304 if (MD_LOADSEG(&phdr[i])) 305 goto loadseg; 306 307 if (phdr[i].p_type != PT_LOAD || 308 (phdr[i].p_flags & (PF_W|PF_X)) == 0) 309 continue; 310 311 #define IS_TEXT(p) (p.p_flags & PF_X) 312 #define IS_DATA(p) (p.p_flags & PF_W) 313 #define IS_BSS(p) (p.p_filesz < p.p_memsz) 314 /* 315 * XXX: Assume first address is lowest 316 */ 317 if ((IS_TEXT(phdr[i]) && (flags & LOAD_TEXT)) || 318 (IS_DATA(phdr[i]) && (flags & LOAD_DATA))) { 319 320 loadseg: 321 if (marks[MARK_DATA] == 0 && IS_DATA(phdr[i])) 322 marks[MARK_DATA] = LOADADDR(phdr[i].p_vaddr); 323 324 /* Read in segment. */ 325 PROGRESS(("%s%lu", first ? "" : "+", 326 (u_long)phdr[i].p_filesz)); 327 328 if (lseek(fd, phdr[i].p_offset, SEEK_SET) == -1) { 329 WARN(("lseek text")); 330 goto freephdr; 331 } 332 nr = READ(fd, phdr[i].p_vaddr, phdr[i].p_filesz); 333 if (nr == -1) { 334 WARN(("read text error")); 335 goto freephdr; 336 } 337 if (nr != (ssize_t)phdr[i].p_filesz) { 338 errno = EIO; 339 WARN(("read text")); 340 goto freephdr; 341 } 342 first = 0; 343 344 } 345 if ((IS_TEXT(phdr[i]) && (flags & (LOAD_TEXT|COUNT_TEXT))) || 346 (IS_DATA(phdr[i]) && (flags & (LOAD_DATA|COUNT_TEXT)))) { 347 pos = phdr[i].p_vaddr; 348 if (minp > pos) 349 minp = pos; 350 pos += phdr[i].p_filesz; 351 if (maxp < pos) 352 maxp = pos; 353 } 354 355 /* Zero out bss. */ 356 if (IS_BSS(phdr[i]) && (flags & LOAD_BSS)) { 357 PROGRESS(("+%lu", 358 (u_long)(phdr[i].p_memsz - phdr[i].p_filesz))); 359 BZERO((phdr[i].p_vaddr + phdr[i].p_filesz), 360 phdr[i].p_memsz - phdr[i].p_filesz); 361 } 362 if (IS_BSS(phdr[i]) && (flags & (LOAD_BSS|COUNT_BSS))) { 363 pos += phdr[i].p_memsz - phdr[i].p_filesz; 364 if (maxp < pos) 365 maxp = pos; 366 } 367 } 368 DEALLOC(phdr, sz); 369 370 /* 371 * Copy the ELF and section headers. 372 */ 373 maxp = roundup(maxp, ELFROUND); 374 if (flags & (LOAD_HDR|COUNT_HDR)) { 375 elfp = maxp; 376 maxp += sizeof(Elf_Ehdr); 377 } 378 379 if (flags & (LOAD_SYM|COUNT_SYM)) { 380 if (lseek(fd, elf->e_shoff, SEEK_SET) == -1) { 381 WARN(("lseek section headers")); 382 return 1; 383 } 384 sz = elf->e_shnum * sizeof(Elf_Shdr); 385 386 shp = ALLOC(sz); 387 388 nr = read(fd, shp, sz); 389 if (nr == -1) { 390 WARN(("read section headers")); 391 goto freeshp; 392 } 393 if (nr != sz) { 394 errno = EIO; 395 WARN(("read section headers")); 396 goto freeshp; 397 } 398 399 shpp = maxp; 400 maxp += roundup(sz, ELFROUND); 401 402 #ifndef _STANDALONE 403 /* Internalize the section headers. */ 404 for (i = 0; i < elf->e_shnum; i++) 405 internalize_shdr(elf->e_ident[EI_DATA], &shp[i]); 406 #endif /* ! _STANDALONE */ 407 408 /* 409 * Now load the symbol sections themselves. Make sure 410 * the sections are aligned. Don't bother with any 411 * string table that isn't referenced by a symbol 412 * table. 413 */ 414 for (first = 1, i = 0; i < elf->e_shnum; i++) { 415 switch (shp[i].sh_type) { 416 case SHT_STRTAB: 417 for (j = 0; j < elf->e_shnum; j++) 418 if (shp[j].sh_type == SHT_SYMTAB && 419 shp[j].sh_link == (unsigned int)i) 420 goto havesym; 421 /* FALLTHROUGH */ 422 default: 423 /* Not loading this, so zero out the offset. */ 424 shp[i].sh_offset = 0; 425 break; 426 havesym: 427 case SHT_SYMTAB: 428 if (flags & LOAD_SYM) { 429 PROGRESS(("%s%ld", first ? " [" : "+", 430 (u_long)shp[i].sh_size)); 431 if (lseek(fd, shp[i].sh_offset, 432 SEEK_SET) == -1) { 433 WARN(("lseek symbols")); 434 goto freeshp; 435 } 436 nr = READ(fd, maxp, shp[i].sh_size); 437 if (nr == -1) { 438 WARN(("read symbols")); 439 goto freeshp; 440 } 441 if (nr != (ssize_t)shp[i].sh_size) { 442 errno = EIO; 443 WARN(("read symbols")); 444 goto freeshp; 445 } 446 } 447 shp[i].sh_offset = maxp - elfp; 448 maxp += roundup(shp[i].sh_size, ELFROUND); 449 first = 0; 450 break; 451 case SHT_NOTE: 452 if ((flags & LOAD_NOTE) == 0) 453 break; 454 if (shp[i].sh_size < sizeof(note)) { 455 shp[i].sh_offset = 0; 456 break; 457 } 458 if (lseek(fd, shp[i].sh_offset, SEEK_SET) 459 == -1) { 460 WARN(("lseek note")); 461 goto freeshp; 462 } 463 nr = read(fd, ¬e, sizeof(note)); 464 if (nr == -1) { 465 WARN(("read note")); 466 goto freeshp; 467 } 468 if (note.nh.n_namesz == 469 ELF_NOTE_NETBSD_NAMESZ && 470 note.nh.n_descsz == 471 ELF_NOTE_NETBSD_DESCSZ && 472 note.nh.n_type == 473 ELF_NOTE_TYPE_NETBSD_TAG && 474 memcmp(note.name, ELF_NOTE_NETBSD_NAME, 475 sizeof(note.name)) == 0) { 476 memcpy(&netbsd_version, ¬e.desc, 477 sizeof(netbsd_version)); 478 } 479 shp[i].sh_offset = 0; 480 break; 481 } 482 /* Since we don't load .shstrtab, zero the name. */ 483 shp[i].sh_name = 0; 484 } 485 if (flags & LOAD_SYM) { 486 #ifndef _STANDALONE 487 /* Externalize the section headers. */ 488 for (i = 0; i < elf->e_shnum; i++) 489 externalize_shdr(elf->e_ident[EI_DATA], 490 &shp[i]); 491 #endif /* ! _STANDALONE */ 492 BCOPY(shp, shpp, sz); 493 494 if (first == 0) 495 PROGRESS(("]")); 496 } 497 DEALLOC(shp, sz); 498 } 499 500 /* 501 * Frob the copied ELF header to give information relative 502 * to elfp. 503 */ 504 if (flags & LOAD_HDR) { 505 elf->e_phoff = 0; 506 elf->e_shoff = sizeof(Elf_Ehdr); 507 elf->e_phentsize = 0; 508 elf->e_phnum = 0; 509 elf->e_shstrndx = SHN_UNDEF; 510 externalize_ehdr(elf->e_ident[EI_DATA], elf); 511 BCOPY(elf, elfp, sizeof(*elf)); 512 internalize_ehdr(elf->e_ident[EI_DATA], elf); 513 } 514 515 marks[MARK_START] = LOADADDR(minp); 516 marks[MARK_ENTRY] = LOADADDR(elf->e_entry); 517 /* 518 * Since there can be more than one symbol section in the code 519 * and we need to find strtab too in order to do anything 520 * useful with the symbols, we just pass the whole elf 521 * header back and we let the kernel debugger find the 522 * location and number of symbols by itself. 523 */ 524 marks[MARK_NSYM] = 1; /* XXX: Kernel needs >= 0 */ 525 marks[MARK_SYM] = LOADADDR(elfp); 526 marks[MARK_END] = LOADADDR(maxp); 527 return 0; 528 freephdr: 529 DEALLOC(phdr, sz); 530 return 1; 531 freeshp: 532 DEALLOC(shp, sz); 533 return 1; 534 } 535 536 #ifdef TEST 537 #include <stdlib.h> 538 #include <fcntl.h> 539 #include <err.h> 540 #include <stdio.h> 541 u_int32_t netbsd_version; 542 int 543 main(int argc, char *argv[]) 544 { 545 int fd; 546 u_long marks[MARK_MAX]; 547 Elf_Ehdr elf; 548 if (argc != 2) { 549 (void)fprintf(stderr, "Usage: %s <file>\n", getprogname()); 550 return 1; 551 } 552 if ((fd = open(argv[1], O_RDONLY)) == -1) 553 err(1, "Can't open `%s'", argv[1]); 554 if (read(fd, &elf, sizeof(elf)) != sizeof(elf)) 555 err(1, "Can't read `%s'", argv[1]); 556 memset(marks, 0, sizeof(marks)); 557 marks[MARK_START] = (u_long)malloc(2LL * 1024 * 2024 * 1024); 558 ELFNAMEEND(loadfile)(fd, &elf, marks, LOAD_ALL); 559 printf("%d\n", netbsd_version); 560 return 0; 561 } 562 #endif 563 564 #endif /* (ELFSIZE == 32 && BOOT_ELF32) || (ELFSIZE == 64 && BOOT_ELF64) */ 565