1 /*- 2 * Copyright (c) 1998 Michael Smith <msmith@freebsd.org> 3 * Copyright (c) 1998 Peter Wemm <peter@freebsd.org> 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 #include <sys/cdefs.h> 29 __FBSDID("$FreeBSD$"); 30 31 #include <sys/param.h> 32 #include <sys/endian.h> 33 #include <sys/exec.h> 34 #include <sys/linker.h> 35 #include <sys/module.h> 36 #include <sys/stdint.h> 37 #include <string.h> 38 #include <machine/elf.h> 39 #include <stand.h> 40 #define FREEBSD_ELF 41 #include <sys/link_elf.h> 42 43 #include "bootstrap.h" 44 45 #define COPYOUT(s,d,l) archsw.arch_copyout((vm_offset_t)(s), d, l) 46 47 #if defined(__i386__) && __ELF_WORD_SIZE == 64 48 #undef ELF_TARG_CLASS 49 #undef ELF_TARG_MACH 50 #define ELF_TARG_CLASS ELFCLASS64 51 #define ELF_TARG_MACH EM_X86_64 52 #endif 53 54 typedef struct elf_file { 55 Elf_Phdr *ph; 56 Elf_Ehdr *ehdr; 57 Elf_Sym *symtab; 58 Elf_Hashelt *hashtab; 59 Elf_Hashelt nbuckets; 60 Elf_Hashelt nchains; 61 Elf_Hashelt *buckets; 62 Elf_Hashelt *chains; 63 Elf_Rel *rel; 64 size_t relsz; 65 Elf_Rela *rela; 66 size_t relasz; 67 char *strtab; 68 size_t strsz; 69 int fd; 70 caddr_t firstpage; 71 size_t firstlen; 72 int kernel; 73 uint64_t off; 74 } *elf_file_t; 75 76 static int __elfN(loadimage)(struct preloaded_file *mp, elf_file_t ef, 77 uint64_t loadaddr); 78 static int __elfN(lookup_symbol)(struct preloaded_file *mp, elf_file_t ef, 79 const char* name, Elf_Sym* sym); 80 static int __elfN(reloc_ptr)(struct preloaded_file *mp, elf_file_t ef, 81 Elf_Addr p, void *val, size_t len); 82 static int __elfN(parse_modmetadata)(struct preloaded_file *mp, elf_file_t ef, 83 Elf_Addr p_start, Elf_Addr p_end); 84 static symaddr_fn __elfN(symaddr); 85 static char *fake_modname(const char *name); 86 87 const char *__elfN(kerneltype) = "elf kernel"; 88 const char *__elfN(moduletype) = "elf module"; 89 90 uint64_t __elfN(relocation_offset) = 0; 91 92 extern void elf_wrong_field_size(void); 93 #define CONVERT_FIELD(b, f, e) \ 94 switch (sizeof((b)->f)) { \ 95 case 2: \ 96 (b)->f = e ## 16toh((b)->f); \ 97 break; \ 98 case 4: \ 99 (b)->f = e ## 32toh((b)->f); \ 100 break; \ 101 case 8: \ 102 (b)->f = e ## 64toh((b)->f); \ 103 break; \ 104 default: \ 105 /* Force a link time error. */ \ 106 elf_wrong_field_size(); \ 107 break; \ 108 } 109 110 #define CONVERT_SWITCH(h, d, f) \ 111 switch ((h)->e_ident[EI_DATA]) { \ 112 case ELFDATA2MSB: \ 113 f(d, be); \ 114 break; \ 115 case ELFDATA2LSB: \ 116 f(d, le); \ 117 break; \ 118 default: \ 119 return (EINVAL); \ 120 } 121 122 123 static int elf_header_convert(Elf_Ehdr *ehdr) 124 { 125 /* 126 * Fixup ELF header endianness. 127 * 128 * The Xhdr structure was loaded using block read call to optimize file 129 * accesses. It might happen, that the endianness of the system memory 130 * is different that endianness of the ELF header. Swap fields here to 131 * guarantee that Xhdr always contain valid data regardless of 132 * architecture. 133 */ 134 #define HEADER_FIELDS(b, e) \ 135 CONVERT_FIELD(b, e_type, e); \ 136 CONVERT_FIELD(b, e_machine, e); \ 137 CONVERT_FIELD(b, e_version, e); \ 138 CONVERT_FIELD(b, e_entry, e); \ 139 CONVERT_FIELD(b, e_phoff, e); \ 140 CONVERT_FIELD(b, e_shoff, e); \ 141 CONVERT_FIELD(b, e_flags, e); \ 142 CONVERT_FIELD(b, e_ehsize, e); \ 143 CONVERT_FIELD(b, e_phentsize, e); \ 144 CONVERT_FIELD(b, e_phnum, e); \ 145 CONVERT_FIELD(b, e_shentsize, e); \ 146 CONVERT_FIELD(b, e_shnum, e); \ 147 CONVERT_FIELD(b, e_shstrndx, e) 148 149 CONVERT_SWITCH(ehdr, ehdr, HEADER_FIELDS); 150 151 #undef HEADER_FIELDS 152 153 return (0); 154 } 155 156 static int elf_program_header_convert(const Elf_Ehdr *ehdr, Elf_Phdr *phdr) 157 { 158 #define PROGRAM_HEADER_FIELDS(b, e) \ 159 CONVERT_FIELD(b, p_type, e); \ 160 CONVERT_FIELD(b, p_flags, e); \ 161 CONVERT_FIELD(b, p_offset, e); \ 162 CONVERT_FIELD(b, p_vaddr, e); \ 163 CONVERT_FIELD(b, p_paddr, e); \ 164 CONVERT_FIELD(b, p_filesz, e); \ 165 CONVERT_FIELD(b, p_memsz, e); \ 166 CONVERT_FIELD(b, p_align, e) 167 168 CONVERT_SWITCH(ehdr, phdr, PROGRAM_HEADER_FIELDS); 169 170 #undef PROGRAM_HEADER_FIELDS 171 172 return (0); 173 } 174 175 static int elf_section_header_convert(const Elf_Ehdr *ehdr, Elf_Shdr *shdr) 176 { 177 #define SECTION_HEADER_FIELDS(b, e) \ 178 CONVERT_FIELD(b, sh_name, e); \ 179 CONVERT_FIELD(b, sh_type, e); \ 180 CONVERT_FIELD(b, sh_link, e); \ 181 CONVERT_FIELD(b, sh_info, e); \ 182 CONVERT_FIELD(b, sh_flags, e); \ 183 CONVERT_FIELD(b, sh_addr, e); \ 184 CONVERT_FIELD(b, sh_offset, e); \ 185 CONVERT_FIELD(b, sh_size, e); \ 186 CONVERT_FIELD(b, sh_addralign, e); \ 187 CONVERT_FIELD(b, sh_entsize, e) 188 189 CONVERT_SWITCH(ehdr, shdr, SECTION_HEADER_FIELDS); 190 191 #undef SECTION_HEADER_FIELDS 192 193 return (0); 194 } 195 #undef CONVERT_SWITCH 196 #undef CONVERT_FIELD 197 198 static int 199 __elfN(load_elf_header)(char *filename, elf_file_t ef) 200 { 201 ssize_t bytes_read; 202 Elf_Ehdr *ehdr; 203 int err; 204 205 /* 206 * Open the image, read and validate the ELF header 207 */ 208 if (filename == NULL) /* can't handle nameless */ 209 return (EFTYPE); 210 if ((ef->fd = open(filename, O_RDONLY)) == -1) 211 return (errno); 212 ef->firstpage = malloc(PAGE_SIZE); 213 if (ef->firstpage == NULL) { 214 close(ef->fd); 215 return (ENOMEM); 216 } 217 bytes_read = read(ef->fd, ef->firstpage, PAGE_SIZE); 218 ef->firstlen = (size_t)bytes_read; 219 if (bytes_read < 0 || ef->firstlen <= sizeof(Elf_Ehdr)) { 220 err = EFTYPE; /* could be EIO, but may be small file */ 221 goto error; 222 } 223 ehdr = ef->ehdr = (Elf_Ehdr *)ef->firstpage; 224 225 /* Is it ELF? */ 226 if (!IS_ELF(*ehdr)) { 227 err = EFTYPE; 228 goto error; 229 } 230 231 if (ehdr->e_ident[EI_CLASS] != ELF_TARG_CLASS || /* Layout ? */ 232 ehdr->e_ident[EI_DATA] != ELF_TARG_DATA || 233 ehdr->e_ident[EI_VERSION] != EV_CURRENT) /* Version ? */ { 234 err = EFTYPE; 235 goto error; 236 } 237 238 err = elf_header_convert(ehdr); 239 if (err) 240 goto error; 241 242 if (ehdr->e_version != EV_CURRENT || ehdr->e_machine != ELF_TARG_MACH) { 243 /* Machine ? */ 244 err = EFTYPE; 245 goto error; 246 } 247 248 return (0); 249 250 error: 251 if (ef->firstpage != NULL) { 252 free(ef->firstpage); 253 ef->firstpage = NULL; 254 } 255 if (ef->fd != -1) { 256 close(ef->fd); 257 ef->fd = -1; 258 } 259 return (err); 260 } 261 262 /* 263 * Attempt to load the file (file) as an ELF module. It will be stored at 264 * (dest), and a pointer to a module structure describing the loaded object 265 * will be saved in (result). 266 */ 267 int 268 __elfN(loadfile)(char *filename, uint64_t dest, struct preloaded_file **result) 269 { 270 return (__elfN(loadfile_raw)(filename, dest, result, 0)); 271 } 272 273 int 274 __elfN(loadfile_raw)(char *filename, uint64_t dest, 275 struct preloaded_file **result, int multiboot) 276 { 277 struct preloaded_file *fp, *kfp; 278 struct elf_file ef; 279 Elf_Ehdr *ehdr; 280 int err; 281 282 fp = NULL; 283 bzero(&ef, sizeof(struct elf_file)); 284 ef.fd = -1; 285 286 err = __elfN(load_elf_header)(filename, &ef); 287 if (err != 0) 288 return (err); 289 290 ehdr = ef.ehdr; 291 292 /* 293 * Check to see what sort of module we are. 294 */ 295 kfp = file_findfile(NULL, __elfN(kerneltype)); 296 #ifdef __powerpc__ 297 /* 298 * Kernels can be ET_DYN, so just assume the first loaded object is the 299 * kernel. This assumption will be checked later. 300 */ 301 if (kfp == NULL) 302 ef.kernel = 1; 303 #endif 304 if (ef.kernel || ehdr->e_type == ET_EXEC) { 305 /* Looks like a kernel */ 306 if (kfp != NULL) { 307 printf("elf" __XSTRING(__ELF_WORD_SIZE) 308 "_loadfile: kernel already loaded\n"); 309 err = EPERM; 310 goto oerr; 311 } 312 /* 313 * Calculate destination address based on kernel entrypoint. 314 * 315 * For ARM, the destination address is independent of any values 316 * in the elf header (an ARM kernel can be loaded at any 2MB 317 * boundary), so we leave dest set to the value calculated by 318 * archsw.arch_loadaddr() and passed in to this function. 319 */ 320 #ifndef __arm__ 321 if (ehdr->e_type == ET_EXEC) 322 dest = (ehdr->e_entry & ~PAGE_MASK); 323 #endif 324 if ((ehdr->e_entry & ~PAGE_MASK) == 0) { 325 printf("elf" __XSTRING(__ELF_WORD_SIZE) 326 "_loadfile: not a kernel (maybe static binary?)\n"); 327 err = EPERM; 328 goto oerr; 329 } 330 ef.kernel = 1; 331 332 } else if (ehdr->e_type == ET_DYN) { 333 /* Looks like a kld module */ 334 if (multiboot != 0) { 335 printf("elf" __XSTRING(__ELF_WORD_SIZE) 336 "_loadfile: can't load module as multiboot\n"); 337 err = EPERM; 338 goto oerr; 339 } 340 if (kfp == NULL) { 341 printf("elf" __XSTRING(__ELF_WORD_SIZE) 342 "_loadfile: can't load module before kernel\n"); 343 err = EPERM; 344 goto oerr; 345 } 346 if (strcmp(__elfN(kerneltype), kfp->f_type)) { 347 printf("elf" __XSTRING(__ELF_WORD_SIZE) 348 "_loadfile: can't load module with kernel type '%s'\n", 349 kfp->f_type); 350 err = EPERM; 351 goto oerr; 352 } 353 /* Looks OK, got ahead */ 354 ef.kernel = 0; 355 356 } else { 357 err = EFTYPE; 358 goto oerr; 359 } 360 361 if (archsw.arch_loadaddr != NULL) 362 dest = archsw.arch_loadaddr(LOAD_ELF, ehdr, dest); 363 else 364 dest = roundup(dest, PAGE_SIZE); 365 366 /* 367 * Ok, we think we should handle this. 368 */ 369 fp = file_alloc(); 370 if (fp == NULL) { 371 printf("elf" __XSTRING(__ELF_WORD_SIZE) 372 "_loadfile: cannot allocate module info\n"); 373 err = EPERM; 374 goto out; 375 } 376 if (ef.kernel == 1 && multiboot == 0) 377 setenv("kernelname", filename, 1); 378 fp->f_name = strdup(filename); 379 if (multiboot == 0) 380 fp->f_type = strdup(ef.kernel ? 381 __elfN(kerneltype) : __elfN(moduletype)); 382 else 383 fp->f_type = strdup("elf multiboot kernel"); 384 385 #ifdef ELF_VERBOSE 386 if (ef.kernel) 387 printf("%s entry at 0x%jx\n", filename, 388 (uintmax_t)ehdr->e_entry); 389 #else 390 printf("%s ", filename); 391 #endif 392 393 fp->f_size = __elfN(loadimage)(fp, &ef, dest); 394 if (fp->f_size == 0 || fp->f_addr == 0) 395 goto ioerr; 396 397 /* save exec header as metadata */ 398 file_addmetadata(fp, MODINFOMD_ELFHDR, sizeof(*ehdr), ehdr); 399 400 /* Load OK, return module pointer */ 401 *result = (struct preloaded_file *)fp; 402 err = 0; 403 goto out; 404 405 ioerr: 406 err = EIO; 407 oerr: 408 file_discard(fp); 409 out: 410 if (ef.firstpage) 411 free(ef.firstpage); 412 if (ef.fd != -1) 413 close(ef.fd); 414 return (err); 415 } 416 417 /* 418 * With the file (fd) open on the image, and (ehdr) containing 419 * the Elf header, load the image at (off) 420 */ 421 static int 422 __elfN(loadimage)(struct preloaded_file *fp, elf_file_t ef, uint64_t off) 423 { 424 int i; 425 u_int j; 426 Elf_Ehdr *ehdr; 427 Elf_Phdr *phdr, *php; 428 Elf_Shdr *shdr; 429 char *shstr; 430 int ret; 431 vm_offset_t firstaddr; 432 vm_offset_t lastaddr; 433 size_t chunk; 434 ssize_t result; 435 Elf_Addr ssym, esym; 436 Elf_Dyn *dp; 437 Elf_Addr adp; 438 Elf_Addr ctors; 439 int ndp; 440 int symstrindex; 441 int symtabindex; 442 Elf_Size size; 443 u_int fpcopy; 444 Elf_Sym sym; 445 Elf_Addr p_start, p_end; 446 447 dp = NULL; 448 shdr = NULL; 449 ret = 0; 450 firstaddr = lastaddr = 0; 451 ehdr = ef->ehdr; 452 if (ehdr->e_type == ET_EXEC) { 453 #if defined(__i386__) || defined(__amd64__) 454 #if __ELF_WORD_SIZE == 64 455 /* x86_64 relocates after locore */ 456 off = - (off & 0xffffffffff000000ull); 457 #else 458 /* i386 relocates after locore */ 459 off = - (off & 0xff000000u); 460 #endif 461 #elif defined(__powerpc__) 462 /* 463 * On the purely virtual memory machines like e500, the kernel 464 * is linked against its final VA range, which is most often 465 * not available at the loader stage, but only after kernel 466 * initializes and completes its VM settings. In such cases we 467 * cannot use p_vaddr field directly to load ELF segments, but 468 * put them at some 'load-time' locations. 469 */ 470 if (off & 0xf0000000u) { 471 off = -(off & 0xf0000000u); 472 /* 473 * XXX the physical load address should not be 474 * hardcoded. Note that the Book-E kernel assumes that 475 * it's loaded at a 16MB boundary for now... 476 */ 477 off += 0x01000000; 478 ehdr->e_entry += off; 479 #ifdef ELF_VERBOSE 480 printf("Converted entry 0x%08x\n", ehdr->e_entry); 481 #endif 482 } else 483 off = 0; 484 #elif defined(__arm__) && !defined(EFI) 485 /* 486 * The elf headers in arm kernels specify virtual addresses in 487 * all header fields, even the ones that should be physical 488 * addresses. We assume the entry point is in the first page, 489 * and masking the page offset will leave us with the virtual 490 * address the kernel was linked at. We subtract that from the 491 * load offset, making 'off' into the value which, when added 492 * to a virtual address in an elf header, translates it to a 493 * physical address. We do the va->pa conversion on the entry 494 * point address in the header now, so that later we can launch 495 * the kernel by just jumping to that address. 496 * 497 * When booting from UEFI the copyin and copyout functions 498 * handle adjusting the location relative to the first virtual 499 * address. Because of this there is no need to adjust the 500 * offset or entry point address as these will both be handled 501 * by the efi code. 502 */ 503 off -= ehdr->e_entry & ~PAGE_MASK; 504 ehdr->e_entry += off; 505 #ifdef ELF_VERBOSE 506 printf("ehdr->e_entry 0x%08x, va<->pa off %llx\n", 507 ehdr->e_entry, off); 508 #endif 509 #else 510 off = 0; /* other archs use direct mapped kernels */ 511 #endif 512 } 513 ef->off = off; 514 515 if (ef->kernel) 516 __elfN(relocation_offset) = off; 517 518 if ((ehdr->e_phoff + ehdr->e_phnum * sizeof(*phdr)) > ef->firstlen) { 519 printf("elf" __XSTRING(__ELF_WORD_SIZE) 520 "_loadimage: program header not within first page\n"); 521 goto out; 522 } 523 phdr = (Elf_Phdr *)(ef->firstpage + ehdr->e_phoff); 524 525 for (i = 0; i < ehdr->e_phnum; i++) { 526 if (elf_program_header_convert(ehdr, phdr)) 527 continue; 528 529 /* We want to load PT_LOAD segments only.. */ 530 if (phdr[i].p_type != PT_LOAD) 531 continue; 532 533 #ifdef ELF_VERBOSE 534 printf("Segment: 0x%lx@0x%lx -> 0x%lx-0x%lx", 535 (long)phdr[i].p_filesz, (long)phdr[i].p_offset, 536 (long)(phdr[i].p_vaddr + off), 537 (long)(phdr[i].p_vaddr + off + phdr[i].p_memsz - 1)); 538 #else 539 if ((phdr[i].p_flags & PF_W) == 0) { 540 printf("text=0x%lx ", (long)phdr[i].p_filesz); 541 } else { 542 printf("data=0x%lx", (long)phdr[i].p_filesz); 543 if (phdr[i].p_filesz < phdr[i].p_memsz) 544 printf("+0x%lx", (long)(phdr[i].p_memsz - 545 phdr[i].p_filesz)); 546 printf(" "); 547 } 548 #endif 549 fpcopy = 0; 550 if (ef->firstlen > phdr[i].p_offset) { 551 fpcopy = ef->firstlen - phdr[i].p_offset; 552 archsw.arch_copyin(ef->firstpage + phdr[i].p_offset, 553 phdr[i].p_vaddr + off, fpcopy); 554 } 555 if (phdr[i].p_filesz > fpcopy) { 556 if (kern_pread(ef->fd, phdr[i].p_vaddr + off + fpcopy, 557 phdr[i].p_filesz - fpcopy, 558 phdr[i].p_offset + fpcopy) != 0) { 559 printf("\nelf" __XSTRING(__ELF_WORD_SIZE) 560 "_loadimage: read failed\n"); 561 goto out; 562 } 563 } 564 /* clear space from oversized segments; eg: bss */ 565 if (phdr[i].p_filesz < phdr[i].p_memsz) { 566 #ifdef ELF_VERBOSE 567 printf(" (bss: 0x%lx-0x%lx)", 568 (long)(phdr[i].p_vaddr + off + phdr[i].p_filesz), 569 (long)(phdr[i].p_vaddr + off + phdr[i].p_memsz -1)); 570 #endif 571 572 kern_bzero(phdr[i].p_vaddr + off + phdr[i].p_filesz, 573 phdr[i].p_memsz - phdr[i].p_filesz); 574 } 575 #ifdef ELF_VERBOSE 576 printf("\n"); 577 #endif 578 579 if (archsw.arch_loadseg != NULL) 580 archsw.arch_loadseg(ehdr, phdr + i, off); 581 582 if (firstaddr == 0 || firstaddr > (phdr[i].p_vaddr + off)) 583 firstaddr = phdr[i].p_vaddr + off; 584 if (lastaddr == 0 || lastaddr < 585 (phdr[i].p_vaddr + off + phdr[i].p_memsz)) 586 lastaddr = phdr[i].p_vaddr + off + phdr[i].p_memsz; 587 } 588 lastaddr = roundup(lastaddr, sizeof(long)); 589 590 /* 591 * Get the section headers. We need this for finding the .ctors 592 * section as well as for loading any symbols. Both may be hard 593 * to do if reading from a .gz file as it involves seeking. I 594 * think the rule is going to have to be that you must strip a 595 * file to remove symbols before gzipping it. 596 */ 597 chunk = (size_t)ehdr->e_shnum * (size_t)ehdr->e_shentsize; 598 if (chunk == 0 || ehdr->e_shoff == 0) 599 goto nosyms; 600 shdr = alloc_pread(ef->fd, ehdr->e_shoff, chunk); 601 if (shdr == NULL) { 602 printf("\nelf" __XSTRING(__ELF_WORD_SIZE) 603 "_loadimage: failed to read section headers"); 604 goto nosyms; 605 } 606 607 for (i = 0; i < ehdr->e_shnum; i++) 608 elf_section_header_convert(ehdr, &shdr[i]); 609 610 file_addmetadata(fp, MODINFOMD_SHDR, chunk, shdr); 611 612 /* 613 * Read the section string table and look for the .ctors section. 614 * We need to tell the kernel where it is so that it can call the 615 * ctors. 616 */ 617 chunk = shdr[ehdr->e_shstrndx].sh_size; 618 if (chunk) { 619 shstr = alloc_pread(ef->fd, shdr[ehdr->e_shstrndx].sh_offset, 620 chunk); 621 if (shstr) { 622 for (i = 0; i < ehdr->e_shnum; i++) { 623 if (strcmp(shstr + shdr[i].sh_name, 624 ".ctors") != 0) 625 continue; 626 ctors = shdr[i].sh_addr; 627 file_addmetadata(fp, MODINFOMD_CTORS_ADDR, 628 sizeof(ctors), &ctors); 629 size = shdr[i].sh_size; 630 file_addmetadata(fp, MODINFOMD_CTORS_SIZE, 631 sizeof(size), &size); 632 break; 633 } 634 free(shstr); 635 } 636 } 637 638 /* 639 * Now load any symbols. 640 */ 641 symtabindex = -1; 642 symstrindex = -1; 643 for (i = 0; i < ehdr->e_shnum; i++) { 644 if (shdr[i].sh_type != SHT_SYMTAB) 645 continue; 646 for (j = 0; j < ehdr->e_phnum; j++) { 647 if (phdr[j].p_type != PT_LOAD) 648 continue; 649 if (shdr[i].sh_offset >= phdr[j].p_offset && 650 (shdr[i].sh_offset + shdr[i].sh_size <= 651 phdr[j].p_offset + phdr[j].p_filesz)) { 652 shdr[i].sh_offset = 0; 653 shdr[i].sh_size = 0; 654 break; 655 } 656 } 657 if (shdr[i].sh_offset == 0 || shdr[i].sh_size == 0) 658 continue; /* alread loaded in a PT_LOAD above */ 659 /* Save it for loading below */ 660 symtabindex = i; 661 symstrindex = shdr[i].sh_link; 662 } 663 if (symtabindex < 0 || symstrindex < 0) 664 goto nosyms; 665 666 /* Ok, committed to a load. */ 667 #ifndef ELF_VERBOSE 668 printf("syms=["); 669 #endif 670 ssym = lastaddr; 671 for (i = symtabindex; i >= 0; i = symstrindex) { 672 #ifdef ELF_VERBOSE 673 char *secname; 674 675 switch(shdr[i].sh_type) { 676 case SHT_SYMTAB: /* Symbol table */ 677 secname = "symtab"; 678 break; 679 case SHT_STRTAB: /* String table */ 680 secname = "strtab"; 681 break; 682 default: 683 secname = "WHOA!!"; 684 break; 685 } 686 #endif 687 size = shdr[i].sh_size; 688 #if defined(__powerpc__) 689 #if __ELF_WORD_SIZE == 64 690 size = htobe64(size); 691 #else 692 size = htobe32(size); 693 #endif 694 #endif 695 696 archsw.arch_copyin(&size, lastaddr, sizeof(size)); 697 lastaddr += sizeof(size); 698 699 #ifdef ELF_VERBOSE 700 printf("\n%s: 0x%jx@0x%jx -> 0x%jx-0x%jx", secname, 701 (uintmax_t)shdr[i].sh_size, (uintmax_t)shdr[i].sh_offset, 702 (uintmax_t)lastaddr, 703 (uintmax_t)(lastaddr + shdr[i].sh_size)); 704 #else 705 if (i == symstrindex) 706 printf("+"); 707 printf("0x%lx+0x%lx", (long)sizeof(size), (long)size); 708 #endif 709 710 if (lseek(ef->fd, (off_t)shdr[i].sh_offset, SEEK_SET) == -1) { 711 printf("\nelf" __XSTRING(__ELF_WORD_SIZE) 712 "_loadimage: could not seek for symbols - skipped!"); 713 lastaddr = ssym; 714 ssym = 0; 715 goto nosyms; 716 } 717 result = archsw.arch_readin(ef->fd, lastaddr, shdr[i].sh_size); 718 if (result < 0 || (size_t)result != shdr[i].sh_size) { 719 printf("\nelf" __XSTRING(__ELF_WORD_SIZE) 720 "_loadimage: could not read symbols - skipped! " 721 "(%ju != %ju)", (uintmax_t)result, 722 (uintmax_t)shdr[i].sh_size); 723 lastaddr = ssym; 724 ssym = 0; 725 goto nosyms; 726 } 727 /* Reset offsets relative to ssym */ 728 lastaddr += shdr[i].sh_size; 729 lastaddr = roundup(lastaddr, sizeof(size)); 730 if (i == symtabindex) 731 symtabindex = -1; 732 else if (i == symstrindex) 733 symstrindex = -1; 734 } 735 esym = lastaddr; 736 #ifndef ELF_VERBOSE 737 printf("]"); 738 #endif 739 740 #if defined(__powerpc__) 741 /* On PowerPC we always need to provide BE data to the kernel */ 742 #if __ELF_WORD_SIZE == 64 743 ssym = htobe64((uint64_t)ssym); 744 esym = htobe64((uint64_t)esym); 745 #else 746 ssym = htobe32((uint32_t)ssym); 747 esym = htobe32((uint32_t)esym); 748 #endif 749 #endif 750 751 file_addmetadata(fp, MODINFOMD_SSYM, sizeof(ssym), &ssym); 752 file_addmetadata(fp, MODINFOMD_ESYM, sizeof(esym), &esym); 753 754 nosyms: 755 printf("\n"); 756 757 ret = lastaddr - firstaddr; 758 fp->f_addr = firstaddr; 759 760 php = NULL; 761 for (i = 0; i < ehdr->e_phnum; i++) { 762 if (phdr[i].p_type == PT_DYNAMIC) { 763 php = phdr + i; 764 adp = php->p_vaddr; 765 file_addmetadata(fp, MODINFOMD_DYNAMIC, sizeof(adp), 766 &adp); 767 break; 768 } 769 } 770 771 if (php == NULL) /* this is bad, we cannot get to symbols or _DYNAMIC */ 772 goto out; 773 774 ndp = php->p_filesz / sizeof(Elf_Dyn); 775 if (ndp == 0) 776 goto out; 777 dp = malloc(php->p_filesz); 778 if (dp == NULL) 779 goto out; 780 archsw.arch_copyout(php->p_vaddr + off, dp, php->p_filesz); 781 782 ef->strsz = 0; 783 for (i = 0; i < ndp; i++) { 784 if (dp[i].d_tag == 0) 785 break; 786 switch (dp[i].d_tag) { 787 case DT_HASH: 788 ef->hashtab = 789 (Elf_Hashelt*)(uintptr_t)(dp[i].d_un.d_ptr + off); 790 break; 791 case DT_STRTAB: 792 ef->strtab = 793 (char *)(uintptr_t)(dp[i].d_un.d_ptr + off); 794 break; 795 case DT_STRSZ: 796 ef->strsz = dp[i].d_un.d_val; 797 break; 798 case DT_SYMTAB: 799 ef->symtab = 800 (Elf_Sym *)(uintptr_t)(dp[i].d_un.d_ptr + off); 801 break; 802 case DT_REL: 803 ef->rel = 804 (Elf_Rel *)(uintptr_t)(dp[i].d_un.d_ptr + off); 805 break; 806 case DT_RELSZ: 807 ef->relsz = dp[i].d_un.d_val; 808 break; 809 case DT_RELA: 810 ef->rela = 811 (Elf_Rela *)(uintptr_t)(dp[i].d_un.d_ptr + off); 812 break; 813 case DT_RELASZ: 814 ef->relasz = dp[i].d_un.d_val; 815 break; 816 default: 817 break; 818 } 819 } 820 if (ef->hashtab == NULL || ef->symtab == NULL || 821 ef->strtab == NULL || ef->strsz == 0) 822 goto out; 823 COPYOUT(ef->hashtab, &ef->nbuckets, sizeof(ef->nbuckets)); 824 COPYOUT(ef->hashtab + 1, &ef->nchains, sizeof(ef->nchains)); 825 ef->buckets = ef->hashtab + 2; 826 ef->chains = ef->buckets + ef->nbuckets; 827 828 if (__elfN(lookup_symbol)(fp, ef, "__start_set_modmetadata_set", 829 &sym) != 0) 830 return 0; 831 p_start = sym.st_value + ef->off; 832 if (__elfN(lookup_symbol)(fp, ef, "__stop_set_modmetadata_set", 833 &sym) != 0) 834 return ENOENT; 835 p_end = sym.st_value + ef->off; 836 837 if (__elfN(parse_modmetadata)(fp, ef, p_start, p_end) == 0) 838 goto out; 839 840 if (ef->kernel) /* kernel must not depend on anything */ 841 goto out; 842 843 out: 844 if (dp) 845 free(dp); 846 if (shdr) 847 free(shdr); 848 return ret; 849 } 850 851 static char invalid_name[] = "bad"; 852 853 char * 854 fake_modname(const char *name) 855 { 856 const char *sp, *ep; 857 char *fp; 858 size_t len; 859 860 sp = strrchr(name, '/'); 861 if (sp) 862 sp++; 863 else 864 sp = name; 865 ep = strrchr(name, '.'); 866 if (ep) { 867 if (ep == name) { 868 sp = invalid_name; 869 ep = invalid_name + sizeof(invalid_name) - 1; 870 } 871 } else 872 ep = name + strlen(name); 873 len = ep - sp; 874 fp = malloc(len + 1); 875 if (fp == NULL) 876 return NULL; 877 memcpy(fp, sp, len); 878 fp[len] = '\0'; 879 return fp; 880 } 881 882 #if (defined(__i386__) || defined(__powerpc__)) && __ELF_WORD_SIZE == 64 883 struct mod_metadata64 { 884 int md_version; /* structure version MDTV_* */ 885 int md_type; /* type of entry MDT_* */ 886 uint64_t md_data; /* specific data */ 887 uint64_t md_cval; /* common string label */ 888 }; 889 #endif 890 #if defined(__amd64__) && __ELF_WORD_SIZE == 32 891 struct mod_metadata32 { 892 int md_version; /* structure version MDTV_* */ 893 int md_type; /* type of entry MDT_* */ 894 uint32_t md_data; /* specific data */ 895 uint32_t md_cval; /* common string label */ 896 }; 897 #endif 898 899 int 900 __elfN(load_modmetadata)(struct preloaded_file *fp, uint64_t dest) 901 { 902 struct elf_file ef; 903 int err, i, j; 904 Elf_Shdr *sh_meta, *shdr = NULL; 905 Elf_Shdr *sh_data[2]; 906 char *shstrtab = NULL; 907 size_t size; 908 Elf_Addr p_start, p_end; 909 910 bzero(&ef, sizeof(struct elf_file)); 911 ef.fd = -1; 912 913 err = __elfN(load_elf_header)(fp->f_name, &ef); 914 if (err != 0) 915 goto out; 916 917 if (ef.kernel == 1 || ef.ehdr->e_type == ET_EXEC) { 918 ef.kernel = 1; 919 } else if (ef.ehdr->e_type != ET_DYN) { 920 err = EFTYPE; 921 goto out; 922 } 923 924 size = (size_t)ef.ehdr->e_shnum * (size_t)ef.ehdr->e_shentsize; 925 shdr = alloc_pread(ef.fd, ef.ehdr->e_shoff, size); 926 if (shdr == NULL) { 927 err = ENOMEM; 928 goto out; 929 } 930 931 /* Load shstrtab. */ 932 shstrtab = alloc_pread(ef.fd, shdr[ef.ehdr->e_shstrndx].sh_offset, 933 shdr[ef.ehdr->e_shstrndx].sh_size); 934 if (shstrtab == NULL) { 935 printf("\nelf" __XSTRING(__ELF_WORD_SIZE) 936 "load_modmetadata: unable to load shstrtab\n"); 937 err = EFTYPE; 938 goto out; 939 } 940 941 /* Find set_modmetadata_set and data sections. */ 942 sh_data[0] = sh_data[1] = sh_meta = NULL; 943 for (i = 0, j = 0; i < ef.ehdr->e_shnum; i++) { 944 if (strcmp(&shstrtab[shdr[i].sh_name], 945 "set_modmetadata_set") == 0) { 946 sh_meta = &shdr[i]; 947 } 948 if ((strcmp(&shstrtab[shdr[i].sh_name], ".data") == 0) || 949 (strcmp(&shstrtab[shdr[i].sh_name], ".rodata") == 0)) { 950 sh_data[j++] = &shdr[i]; 951 } 952 } 953 if (sh_meta == NULL || sh_data[0] == NULL || sh_data[1] == NULL) { 954 printf("\nelf" __XSTRING(__ELF_WORD_SIZE) 955 "load_modmetadata: unable to find set_modmetadata_set or data sections\n"); 956 err = EFTYPE; 957 goto out; 958 } 959 960 /* Load set_modmetadata_set into memory */ 961 err = kern_pread(ef.fd, dest, sh_meta->sh_size, sh_meta->sh_offset); 962 if (err != 0) { 963 printf("\nelf" __XSTRING(__ELF_WORD_SIZE) 964 "load_modmetadata: unable to load set_modmetadata_set: %d\n", err); 965 goto out; 966 } 967 p_start = dest; 968 p_end = dest + sh_meta->sh_size; 969 dest += sh_meta->sh_size; 970 971 /* Load data sections into memory. */ 972 err = kern_pread(ef.fd, dest, sh_data[0]->sh_size, 973 sh_data[0]->sh_offset); 974 if (err != 0) { 975 printf("\nelf" __XSTRING(__ELF_WORD_SIZE) 976 "load_modmetadata: unable to load data: %d\n", err); 977 goto out; 978 } 979 980 /* 981 * We have to increment the dest, so that the offset is the same into 982 * both the .rodata and .data sections. 983 */ 984 ef.off = -(sh_data[0]->sh_addr - dest); 985 dest += (sh_data[1]->sh_addr - sh_data[0]->sh_addr); 986 987 err = kern_pread(ef.fd, dest, sh_data[1]->sh_size, 988 sh_data[1]->sh_offset); 989 if (err != 0) { 990 printf("\nelf" __XSTRING(__ELF_WORD_SIZE) 991 "load_modmetadata: unable to load data: %d\n", err); 992 goto out; 993 } 994 995 err = __elfN(parse_modmetadata)(fp, &ef, p_start, p_end); 996 if (err != 0) { 997 printf("\nelf" __XSTRING(__ELF_WORD_SIZE) 998 "load_modmetadata: unable to parse metadata: %d\n", err); 999 goto out; 1000 } 1001 1002 out: 1003 if (shstrtab != NULL) 1004 free(shstrtab); 1005 if (shdr != NULL) 1006 free(shdr); 1007 if (ef.firstpage != NULL) 1008 free(ef.firstpage); 1009 if (ef.fd != -1) 1010 close(ef.fd); 1011 return (err); 1012 } 1013 1014 int 1015 __elfN(parse_modmetadata)(struct preloaded_file *fp, elf_file_t ef, 1016 Elf_Addr p_start, Elf_Addr p_end) 1017 { 1018 struct mod_metadata md; 1019 #if (defined(__i386__) || defined(__powerpc__)) && __ELF_WORD_SIZE == 64 1020 struct mod_metadata64 md64; 1021 #elif defined(__amd64__) && __ELF_WORD_SIZE == 32 1022 struct mod_metadata32 md32; 1023 #endif 1024 struct mod_depend *mdepend; 1025 struct mod_version mver; 1026 char *s; 1027 int error, modcnt, minfolen; 1028 Elf_Addr v, p; 1029 1030 modcnt = 0; 1031 p = p_start; 1032 while (p < p_end) { 1033 COPYOUT(p, &v, sizeof(v)); 1034 error = __elfN(reloc_ptr)(fp, ef, p, &v, sizeof(v)); 1035 if (error == EOPNOTSUPP) 1036 v += ef->off; 1037 else if (error != 0) 1038 return (error); 1039 #if (defined(__i386__) || defined(__powerpc__)) && __ELF_WORD_SIZE == 64 1040 COPYOUT(v, &md64, sizeof(md64)); 1041 error = __elfN(reloc_ptr)(fp, ef, v, &md64, sizeof(md64)); 1042 if (error == EOPNOTSUPP) { 1043 md64.md_cval += ef->off; 1044 md64.md_data += ef->off; 1045 } else if (error != 0) 1046 return (error); 1047 md.md_version = md64.md_version; 1048 md.md_type = md64.md_type; 1049 md.md_cval = (const char *)(uintptr_t)md64.md_cval; 1050 md.md_data = (void *)(uintptr_t)md64.md_data; 1051 #elif defined(__amd64__) && __ELF_WORD_SIZE == 32 1052 COPYOUT(v, &md32, sizeof(md32)); 1053 error = __elfN(reloc_ptr)(fp, ef, v, &md32, sizeof(md32)); 1054 if (error == EOPNOTSUPP) { 1055 md32.md_cval += ef->off; 1056 md32.md_data += ef->off; 1057 } else if (error != 0) 1058 return (error); 1059 md.md_version = md32.md_version; 1060 md.md_type = md32.md_type; 1061 md.md_cval = (const char *)(uintptr_t)md32.md_cval; 1062 md.md_data = (void *)(uintptr_t)md32.md_data; 1063 #else 1064 COPYOUT(v, &md, sizeof(md)); 1065 error = __elfN(reloc_ptr)(fp, ef, v, &md, sizeof(md)); 1066 if (error == EOPNOTSUPP) { 1067 md.md_cval += ef->off; 1068 md.md_data = (void *)((uintptr_t)md.md_data + 1069 (uintptr_t)ef->off); 1070 } else if (error != 0) 1071 return (error); 1072 #endif 1073 p += sizeof(Elf_Addr); 1074 switch(md.md_type) { 1075 case MDT_DEPEND: 1076 if (ef->kernel) /* kernel must not depend on anything */ 1077 break; 1078 s = strdupout((vm_offset_t)md.md_cval); 1079 minfolen = sizeof(*mdepend) + strlen(s) + 1; 1080 mdepend = malloc(minfolen); 1081 if (mdepend == NULL) 1082 return ENOMEM; 1083 COPYOUT((vm_offset_t)md.md_data, mdepend, 1084 sizeof(*mdepend)); 1085 strcpy((char*)(mdepend + 1), s); 1086 free(s); 1087 file_addmetadata(fp, MODINFOMD_DEPLIST, minfolen, 1088 mdepend); 1089 free(mdepend); 1090 break; 1091 case MDT_VERSION: 1092 s = strdupout((vm_offset_t)md.md_cval); 1093 COPYOUT((vm_offset_t)md.md_data, &mver, sizeof(mver)); 1094 file_addmodule(fp, s, mver.mv_version, NULL); 1095 free(s); 1096 modcnt++; 1097 break; 1098 } 1099 } 1100 if (modcnt == 0) { 1101 s = fake_modname(fp->f_name); 1102 file_addmodule(fp, s, 1, NULL); 1103 free(s); 1104 } 1105 return 0; 1106 } 1107 1108 static unsigned long 1109 elf_hash(const char *name) 1110 { 1111 const unsigned char *p = (const unsigned char *) name; 1112 unsigned long h = 0; 1113 unsigned long g; 1114 1115 while (*p != '\0') { 1116 h = (h << 4) + *p++; 1117 if ((g = h & 0xf0000000) != 0) 1118 h ^= g >> 24; 1119 h &= ~g; 1120 } 1121 return h; 1122 } 1123 1124 static const char __elfN(bad_symtable)[] = "elf" __XSTRING(__ELF_WORD_SIZE) 1125 "_lookup_symbol: corrupt symbol table\n"; 1126 int 1127 __elfN(lookup_symbol)(struct preloaded_file *fp, elf_file_t ef, 1128 const char* name, Elf_Sym *symp) 1129 { 1130 Elf_Hashelt symnum; 1131 Elf_Sym sym; 1132 char *strp; 1133 unsigned long hash; 1134 1135 hash = elf_hash(name); 1136 COPYOUT(&ef->buckets[hash % ef->nbuckets], &symnum, sizeof(symnum)); 1137 1138 while (symnum != STN_UNDEF) { 1139 if (symnum >= ef->nchains) { 1140 printf(__elfN(bad_symtable)); 1141 return ENOENT; 1142 } 1143 1144 COPYOUT(ef->symtab + symnum, &sym, sizeof(sym)); 1145 if (sym.st_name == 0) { 1146 printf(__elfN(bad_symtable)); 1147 return ENOENT; 1148 } 1149 1150 strp = strdupout((vm_offset_t)(ef->strtab + sym.st_name)); 1151 if (strcmp(name, strp) == 0) { 1152 free(strp); 1153 if (sym.st_shndx != SHN_UNDEF || 1154 (sym.st_value != 0 && 1155 ELF_ST_TYPE(sym.st_info) == STT_FUNC)) { 1156 *symp = sym; 1157 return 0; 1158 } 1159 return ENOENT; 1160 } 1161 free(strp); 1162 COPYOUT(&ef->chains[symnum], &symnum, sizeof(symnum)); 1163 } 1164 return ENOENT; 1165 } 1166 1167 /* 1168 * Apply any intra-module relocations to the value. p is the load address 1169 * of the value and val/len is the value to be modified. This does NOT modify 1170 * the image in-place, because this is done by kern_linker later on. 1171 * 1172 * Returns EOPNOTSUPP if no relocation method is supplied. 1173 */ 1174 static int 1175 __elfN(reloc_ptr)(struct preloaded_file *mp, elf_file_t ef, 1176 Elf_Addr p, void *val, size_t len) 1177 { 1178 size_t n; 1179 Elf_Rela a; 1180 Elf_Rel r; 1181 int error; 1182 1183 /* 1184 * The kernel is already relocated, but we still want to apply 1185 * offset adjustments. 1186 */ 1187 if (ef->kernel) 1188 return (EOPNOTSUPP); 1189 1190 for (n = 0; n < ef->relsz / sizeof(r); n++) { 1191 COPYOUT(ef->rel + n, &r, sizeof(r)); 1192 1193 error = __elfN(reloc)(ef, __elfN(symaddr), &r, ELF_RELOC_REL, 1194 ef->off, p, val, len); 1195 if (error != 0) 1196 return (error); 1197 } 1198 for (n = 0; n < ef->relasz / sizeof(a); n++) { 1199 COPYOUT(ef->rela + n, &a, sizeof(a)); 1200 1201 error = __elfN(reloc)(ef, __elfN(symaddr), &a, ELF_RELOC_RELA, 1202 ef->off, p, val, len); 1203 if (error != 0) 1204 return (error); 1205 } 1206 1207 return (0); 1208 } 1209 1210 static Elf_Addr 1211 __elfN(symaddr)(struct elf_file *ef, Elf_Size symidx) 1212 { 1213 1214 /* Symbol lookup by index not required here. */ 1215 return (0); 1216 } 1217