1 /*- 2 * Copyright (c) 1998-2000 Doug Rabson 3 * Copyright (c) 2004 Peter Wemm 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 "opt_ddb.h" 32 33 #include <sys/param.h> 34 #include <sys/systm.h> 35 #include <sys/kernel.h> 36 #include <sys/lock.h> 37 #include <sys/malloc.h> 38 #include <sys/mutex.h> 39 #include <sys/mount.h> 40 #include <sys/proc.h> 41 #include <sys/namei.h> 42 #include <sys/fcntl.h> 43 #include <sys/vnode.h> 44 #include <sys/linker.h> 45 46 #include <machine/elf.h> 47 48 #include <net/vnet.h> 49 50 #include <security/mac/mac_framework.h> 51 52 #include <vm/vm.h> 53 #include <vm/vm_param.h> 54 #include <vm/vm_object.h> 55 #include <vm/vm_kern.h> 56 #include <vm/vm_extern.h> 57 #include <vm/pmap.h> 58 #include <vm/vm_map.h> 59 60 #include <sys/link_elf.h> 61 62 #ifdef DDB_CTF 63 #include <sys/zlib.h> 64 #endif 65 66 #include "linker_if.h" 67 68 typedef struct { 69 void *addr; 70 Elf_Off size; 71 int flags; 72 int sec; /* Original section */ 73 char *name; 74 } Elf_progent; 75 76 typedef struct { 77 Elf_Rel *rel; 78 int nrel; 79 int sec; 80 } Elf_relent; 81 82 typedef struct { 83 Elf_Rela *rela; 84 int nrela; 85 int sec; 86 } Elf_relaent; 87 88 89 typedef struct elf_file { 90 struct linker_file lf; /* Common fields */ 91 92 int preloaded; 93 caddr_t address; /* Relocation address */ 94 vm_object_t object; /* VM object to hold file pages */ 95 Elf_Shdr *e_shdr; 96 97 Elf_progent *progtab; 98 int nprogtab; 99 100 Elf_relaent *relatab; 101 int nrelatab; 102 103 Elf_relent *reltab; 104 int nreltab; 105 106 Elf_Sym *ddbsymtab; /* The symbol table we are using */ 107 long ddbsymcnt; /* Number of symbols */ 108 caddr_t ddbstrtab; /* String table */ 109 long ddbstrcnt; /* number of bytes in string table */ 110 111 caddr_t shstrtab; /* Section name string table */ 112 long shstrcnt; /* number of bytes in string table */ 113 114 caddr_t ctftab; /* CTF table */ 115 long ctfcnt; /* number of bytes in CTF table */ 116 caddr_t ctfoff; /* CTF offset table */ 117 caddr_t typoff; /* Type offset table */ 118 long typlen; /* Number of type entries. */ 119 120 } *elf_file_t; 121 122 #include <kern/kern_ctf.c> 123 124 static int link_elf_link_preload(linker_class_t cls, 125 const char *, linker_file_t *); 126 static int link_elf_link_preload_finish(linker_file_t); 127 static int link_elf_load_file(linker_class_t, const char *, linker_file_t *); 128 static int link_elf_lookup_symbol(linker_file_t, const char *, 129 c_linker_sym_t *); 130 static int link_elf_symbol_values(linker_file_t, c_linker_sym_t, 131 linker_symval_t *); 132 static int link_elf_search_symbol(linker_file_t, caddr_t value, 133 c_linker_sym_t *sym, long *diffp); 134 135 static void link_elf_unload_file(linker_file_t); 136 static int link_elf_lookup_set(linker_file_t, const char *, 137 void ***, void ***, int *); 138 static int link_elf_each_function_name(linker_file_t, 139 int (*)(const char *, void *), void *); 140 static int link_elf_each_function_nameval(linker_file_t, 141 linker_function_nameval_callback_t, 142 void *); 143 static void link_elf_reloc_local(linker_file_t); 144 static long link_elf_symtab_get(linker_file_t, const Elf_Sym **); 145 static long link_elf_strtab_get(linker_file_t, caddr_t *); 146 147 static int elf_obj_lookup(linker_file_t lf, Elf_Size symidx, int deps, 148 Elf_Addr *); 149 150 static kobj_method_t link_elf_methods[] = { 151 KOBJMETHOD(linker_lookup_symbol, link_elf_lookup_symbol), 152 KOBJMETHOD(linker_symbol_values, link_elf_symbol_values), 153 KOBJMETHOD(linker_search_symbol, link_elf_search_symbol), 154 KOBJMETHOD(linker_unload, link_elf_unload_file), 155 KOBJMETHOD(linker_load_file, link_elf_load_file), 156 KOBJMETHOD(linker_link_preload, link_elf_link_preload), 157 KOBJMETHOD(linker_link_preload_finish, link_elf_link_preload_finish), 158 KOBJMETHOD(linker_lookup_set, link_elf_lookup_set), 159 KOBJMETHOD(linker_each_function_name, link_elf_each_function_name), 160 KOBJMETHOD(linker_each_function_nameval, link_elf_each_function_nameval), 161 KOBJMETHOD(linker_ctf_get, link_elf_ctf_get), 162 KOBJMETHOD(linker_symtab_get, link_elf_symtab_get), 163 KOBJMETHOD(linker_strtab_get, link_elf_strtab_get), 164 { 0, 0 } 165 }; 166 167 static struct linker_class link_elf_class = { 168 #if ELF_TARG_CLASS == ELFCLASS32 169 "elf32_obj", 170 #else 171 "elf64_obj", 172 #endif 173 link_elf_methods, sizeof(struct elf_file) 174 }; 175 176 static int relocate_file(elf_file_t ef); 177 static void elf_obj_cleanup_globals_cache(elf_file_t); 178 179 static void 180 link_elf_error(const char *filename, const char *s) 181 { 182 if (filename == NULL) 183 printf("kldload: %s\n", s); 184 else 185 printf("kldload: %s: %s\n", filename, s); 186 } 187 188 static void 189 link_elf_init(void *arg) 190 { 191 192 linker_add_class(&link_elf_class); 193 } 194 195 SYSINIT(link_elf_obj, SI_SUB_KLD, SI_ORDER_SECOND, link_elf_init, 0); 196 197 static int 198 link_elf_link_preload(linker_class_t cls, const char *filename, 199 linker_file_t *result) 200 { 201 Elf_Ehdr *hdr; 202 Elf_Shdr *shdr; 203 Elf_Sym *es; 204 void *modptr, *baseptr, *sizeptr; 205 char *type; 206 elf_file_t ef; 207 linker_file_t lf; 208 Elf_Addr off; 209 int error, i, j, pb, ra, rl, shstrindex, symstrindex, symtabindex; 210 211 /* Look to see if we have the file preloaded */ 212 modptr = preload_search_by_name(filename); 213 if (modptr == NULL) 214 return ENOENT; 215 216 type = (char *)preload_search_info(modptr, MODINFO_TYPE); 217 baseptr = preload_search_info(modptr, MODINFO_ADDR); 218 sizeptr = preload_search_info(modptr, MODINFO_SIZE); 219 hdr = (Elf_Ehdr *)preload_search_info(modptr, MODINFO_METADATA | 220 MODINFOMD_ELFHDR); 221 shdr = (Elf_Shdr *)preload_search_info(modptr, MODINFO_METADATA | 222 MODINFOMD_SHDR); 223 if (type == NULL || (strcmp(type, "elf" __XSTRING(__ELF_WORD_SIZE) 224 " obj module") != 0 && 225 strcmp(type, "elf obj module") != 0)) { 226 return (EFTYPE); 227 } 228 if (baseptr == NULL || sizeptr == NULL || hdr == NULL || 229 shdr == NULL) 230 return (EINVAL); 231 232 lf = linker_make_file(filename, &link_elf_class); 233 if (lf == NULL) 234 return (ENOMEM); 235 236 ef = (elf_file_t)lf; 237 ef->preloaded = 1; 238 ef->address = *(caddr_t *)baseptr; 239 lf->address = *(caddr_t *)baseptr; 240 lf->size = *(size_t *)sizeptr; 241 242 if (hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS || 243 hdr->e_ident[EI_DATA] != ELF_TARG_DATA || 244 hdr->e_ident[EI_VERSION] != EV_CURRENT || 245 hdr->e_version != EV_CURRENT || 246 hdr->e_type != ET_REL || 247 hdr->e_machine != ELF_TARG_MACH) { 248 error = EFTYPE; 249 goto out; 250 } 251 ef->e_shdr = shdr; 252 253 /* Scan the section header for information and table sizing. */ 254 symtabindex = -1; 255 symstrindex = -1; 256 for (i = 0; i < hdr->e_shnum; i++) { 257 switch (shdr[i].sh_type) { 258 case SHT_PROGBITS: 259 case SHT_NOBITS: 260 ef->nprogtab++; 261 break; 262 case SHT_SYMTAB: 263 symtabindex = i; 264 symstrindex = shdr[i].sh_link; 265 break; 266 case SHT_REL: 267 ef->nreltab++; 268 break; 269 case SHT_RELA: 270 ef->nrelatab++; 271 break; 272 } 273 } 274 275 shstrindex = hdr->e_shstrndx; 276 if (ef->nprogtab == 0 || symstrindex < 0 || 277 symstrindex >= hdr->e_shnum || 278 shdr[symstrindex].sh_type != SHT_STRTAB || shstrindex == 0 || 279 shstrindex >= hdr->e_shnum || 280 shdr[shstrindex].sh_type != SHT_STRTAB) { 281 printf("%s: bad/missing section headers\n", filename); 282 error = ENOEXEC; 283 goto out; 284 } 285 286 /* Allocate space for tracking the load chunks */ 287 if (ef->nprogtab != 0) 288 ef->progtab = malloc(ef->nprogtab * sizeof(*ef->progtab), 289 M_LINKER, M_WAITOK | M_ZERO); 290 if (ef->nreltab != 0) 291 ef->reltab = malloc(ef->nreltab * sizeof(*ef->reltab), 292 M_LINKER, M_WAITOK | M_ZERO); 293 if (ef->nrelatab != 0) 294 ef->relatab = malloc(ef->nrelatab * sizeof(*ef->relatab), 295 M_LINKER, M_WAITOK | M_ZERO); 296 if ((ef->nprogtab != 0 && ef->progtab == NULL) || 297 (ef->nreltab != 0 && ef->reltab == NULL) || 298 (ef->nrelatab != 0 && ef->relatab == NULL)) { 299 error = ENOMEM; 300 goto out; 301 } 302 303 /* XXX, relocate the sh_addr fields saved by the loader. */ 304 off = 0; 305 for (i = 0; i < hdr->e_shnum; i++) { 306 if (shdr[i].sh_addr != 0 && (off == 0 || shdr[i].sh_addr < off)) 307 off = shdr[i].sh_addr; 308 } 309 for (i = 0; i < hdr->e_shnum; i++) { 310 if (shdr[i].sh_addr != 0) 311 shdr[i].sh_addr = shdr[i].sh_addr - off + 312 (Elf_Addr)ef->address; 313 } 314 315 ef->ddbsymcnt = shdr[symtabindex].sh_size / sizeof(Elf_Sym); 316 ef->ddbsymtab = (Elf_Sym *)shdr[symtabindex].sh_addr; 317 ef->ddbstrcnt = shdr[symstrindex].sh_size; 318 ef->ddbstrtab = (char *)shdr[symstrindex].sh_addr; 319 ef->shstrcnt = shdr[shstrindex].sh_size; 320 ef->shstrtab = (char *)shdr[shstrindex].sh_addr; 321 322 /* Now fill out progtab and the relocation tables. */ 323 pb = 0; 324 rl = 0; 325 ra = 0; 326 for (i = 0; i < hdr->e_shnum; i++) { 327 switch (shdr[i].sh_type) { 328 case SHT_PROGBITS: 329 case SHT_NOBITS: 330 ef->progtab[pb].addr = (void *)shdr[i].sh_addr; 331 if (shdr[i].sh_type == SHT_PROGBITS) 332 ef->progtab[pb].name = "<<PROGBITS>>"; 333 else 334 ef->progtab[pb].name = "<<NOBITS>>"; 335 ef->progtab[pb].size = shdr[i].sh_size; 336 ef->progtab[pb].sec = i; 337 if (ef->shstrtab && shdr[i].sh_name != 0) 338 ef->progtab[pb].name = 339 ef->shstrtab + shdr[i].sh_name; 340 if (ef->progtab[pb].name != NULL && 341 !strcmp(ef->progtab[pb].name, DPCPU_SETNAME)) { 342 void *dpcpu; 343 344 dpcpu = dpcpu_alloc(shdr[i].sh_size); 345 if (dpcpu == NULL) { 346 error = ENOSPC; 347 goto out; 348 } 349 memcpy(dpcpu, ef->progtab[pb].addr, 350 ef->progtab[pb].size); 351 dpcpu_copy(dpcpu, shdr[i].sh_size); 352 ef->progtab[pb].addr = dpcpu; 353 #ifdef VIMAGE 354 } else if (ef->progtab[pb].name != NULL && 355 !strcmp(ef->progtab[pb].name, VNET_SETNAME)) { 356 void *vnet_data; 357 358 vnet_data = vnet_data_alloc(shdr[i].sh_size); 359 if (vnet_data == NULL) { 360 error = ENOSPC; 361 goto out; 362 } 363 memcpy(vnet_data, ef->progtab[pb].addr, 364 ef->progtab[pb].size); 365 vnet_data_copy(vnet_data, shdr[i].sh_size); 366 ef->progtab[pb].addr = vnet_data; 367 #endif 368 } else if (ef->progtab[pb].name != NULL && 369 !strcmp(ef->progtab[pb].name, ".ctors")) { 370 lf->ctors_addr = ef->progtab[pb].addr; 371 lf->ctors_size = shdr[i].sh_size; 372 } 373 374 /* Update all symbol values with the offset. */ 375 for (j = 0; j < ef->ddbsymcnt; j++) { 376 es = &ef->ddbsymtab[j]; 377 if (es->st_shndx != i) 378 continue; 379 es->st_value += (Elf_Addr)ef->progtab[pb].addr; 380 } 381 pb++; 382 break; 383 case SHT_REL: 384 ef->reltab[rl].rel = (Elf_Rel *)shdr[i].sh_addr; 385 ef->reltab[rl].nrel = shdr[i].sh_size / sizeof(Elf_Rel); 386 ef->reltab[rl].sec = shdr[i].sh_info; 387 rl++; 388 break; 389 case SHT_RELA: 390 ef->relatab[ra].rela = (Elf_Rela *)shdr[i].sh_addr; 391 ef->relatab[ra].nrela = 392 shdr[i].sh_size / sizeof(Elf_Rela); 393 ef->relatab[ra].sec = shdr[i].sh_info; 394 ra++; 395 break; 396 } 397 } 398 if (pb != ef->nprogtab) 399 panic("lost progbits"); 400 if (rl != ef->nreltab) 401 panic("lost reltab"); 402 if (ra != ef->nrelatab) 403 panic("lost relatab"); 404 405 /* Local intra-module relocations */ 406 link_elf_reloc_local(lf); 407 408 *result = lf; 409 return (0); 410 411 out: 412 /* preload not done this way */ 413 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 414 return (error); 415 } 416 417 static void 418 link_elf_invoke_ctors(caddr_t addr, size_t size) 419 { 420 void (**ctor)(void); 421 size_t i, cnt; 422 423 if (addr == NULL || size == 0) 424 return; 425 cnt = size / sizeof(*ctor); 426 ctor = (void *)addr; 427 for (i = 0; i < cnt; i++) { 428 if (ctor[i] != NULL) 429 (*ctor[i])(); 430 } 431 } 432 433 static int 434 link_elf_link_preload_finish(linker_file_t lf) 435 { 436 elf_file_t ef; 437 int error; 438 439 ef = (elf_file_t)lf; 440 error = relocate_file(ef); 441 if (error) 442 return error; 443 444 /* Notify MD code that a module is being loaded. */ 445 error = elf_cpu_load_file(lf); 446 if (error) 447 return (error); 448 449 /* Invoke .ctors */ 450 link_elf_invoke_ctors(lf->ctors_addr, lf->ctors_size); 451 return (0); 452 } 453 454 static int 455 link_elf_load_file(linker_class_t cls, const char *filename, 456 linker_file_t *result) 457 { 458 struct nameidata nd; 459 struct thread *td = curthread; /* XXX */ 460 Elf_Ehdr *hdr; 461 Elf_Shdr *shdr; 462 Elf_Sym *es; 463 int nbytes, i, j; 464 vm_offset_t mapbase; 465 size_t mapsize; 466 int error = 0; 467 ssize_t resid; 468 int flags; 469 elf_file_t ef; 470 linker_file_t lf; 471 int symtabindex; 472 int symstrindex; 473 int shstrindex; 474 int nsym; 475 int pb, rl, ra; 476 int alignmask; 477 478 shdr = NULL; 479 lf = NULL; 480 mapsize = 0; 481 hdr = NULL; 482 483 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, filename, td); 484 flags = FREAD; 485 error = vn_open(&nd, &flags, 0, NULL); 486 if (error) 487 return error; 488 NDFREE(&nd, NDF_ONLY_PNBUF); 489 if (nd.ni_vp->v_type != VREG) { 490 error = ENOEXEC; 491 goto out; 492 } 493 #ifdef MAC 494 error = mac_kld_check_load(td->td_ucred, nd.ni_vp); 495 if (error) { 496 goto out; 497 } 498 #endif 499 500 /* Read the elf header from the file. */ 501 hdr = malloc(sizeof(*hdr), M_LINKER, M_WAITOK); 502 error = vn_rdwr(UIO_READ, nd.ni_vp, (void *)hdr, sizeof(*hdr), 0, 503 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, 504 &resid, td); 505 if (error) 506 goto out; 507 if (resid != 0){ 508 error = ENOEXEC; 509 goto out; 510 } 511 512 if (!IS_ELF(*hdr)) { 513 error = ENOEXEC; 514 goto out; 515 } 516 517 if (hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS 518 || hdr->e_ident[EI_DATA] != ELF_TARG_DATA) { 519 link_elf_error(filename, "Unsupported file layout"); 520 error = ENOEXEC; 521 goto out; 522 } 523 if (hdr->e_ident[EI_VERSION] != EV_CURRENT 524 || hdr->e_version != EV_CURRENT) { 525 link_elf_error(filename, "Unsupported file version"); 526 error = ENOEXEC; 527 goto out; 528 } 529 if (hdr->e_type != ET_REL) { 530 error = ENOSYS; 531 goto out; 532 } 533 if (hdr->e_machine != ELF_TARG_MACH) { 534 link_elf_error(filename, "Unsupported machine"); 535 error = ENOEXEC; 536 goto out; 537 } 538 539 lf = linker_make_file(filename, &link_elf_class); 540 if (!lf) { 541 error = ENOMEM; 542 goto out; 543 } 544 ef = (elf_file_t) lf; 545 ef->nprogtab = 0; 546 ef->e_shdr = 0; 547 ef->nreltab = 0; 548 ef->nrelatab = 0; 549 550 /* Allocate and read in the section header */ 551 nbytes = hdr->e_shnum * hdr->e_shentsize; 552 if (nbytes == 0 || hdr->e_shoff == 0 || 553 hdr->e_shentsize != sizeof(Elf_Shdr)) { 554 error = ENOEXEC; 555 goto out; 556 } 557 shdr = malloc(nbytes, M_LINKER, M_WAITOK); 558 ef->e_shdr = shdr; 559 error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)shdr, nbytes, hdr->e_shoff, 560 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, &resid, td); 561 if (error) 562 goto out; 563 if (resid) { 564 error = ENOEXEC; 565 goto out; 566 } 567 568 /* Scan the section header for information and table sizing. */ 569 nsym = 0; 570 symtabindex = -1; 571 symstrindex = -1; 572 for (i = 0; i < hdr->e_shnum; i++) { 573 if (shdr[i].sh_size == 0) 574 continue; 575 switch (shdr[i].sh_type) { 576 case SHT_PROGBITS: 577 case SHT_NOBITS: 578 ef->nprogtab++; 579 break; 580 case SHT_SYMTAB: 581 nsym++; 582 symtabindex = i; 583 symstrindex = shdr[i].sh_link; 584 break; 585 case SHT_REL: 586 ef->nreltab++; 587 break; 588 case SHT_RELA: 589 ef->nrelatab++; 590 break; 591 case SHT_STRTAB: 592 break; 593 } 594 } 595 if (ef->nprogtab == 0) { 596 link_elf_error(filename, "file has no contents"); 597 error = ENOEXEC; 598 goto out; 599 } 600 if (nsym != 1) { 601 /* Only allow one symbol table for now */ 602 link_elf_error(filename, "file has no valid symbol table"); 603 error = ENOEXEC; 604 goto out; 605 } 606 if (symstrindex < 0 || symstrindex > hdr->e_shnum || 607 shdr[symstrindex].sh_type != SHT_STRTAB) { 608 link_elf_error(filename, "file has invalid symbol strings"); 609 error = ENOEXEC; 610 goto out; 611 } 612 613 /* Allocate space for tracking the load chunks */ 614 if (ef->nprogtab != 0) 615 ef->progtab = malloc(ef->nprogtab * sizeof(*ef->progtab), 616 M_LINKER, M_WAITOK | M_ZERO); 617 if (ef->nreltab != 0) 618 ef->reltab = malloc(ef->nreltab * sizeof(*ef->reltab), 619 M_LINKER, M_WAITOK | M_ZERO); 620 if (ef->nrelatab != 0) 621 ef->relatab = malloc(ef->nrelatab * sizeof(*ef->relatab), 622 M_LINKER, M_WAITOK | M_ZERO); 623 624 if (symtabindex == -1) 625 panic("lost symbol table index"); 626 /* Allocate space for and load the symbol table */ 627 ef->ddbsymcnt = shdr[symtabindex].sh_size / sizeof(Elf_Sym); 628 ef->ddbsymtab = malloc(shdr[symtabindex].sh_size, M_LINKER, M_WAITOK); 629 error = vn_rdwr(UIO_READ, nd.ni_vp, (void *)ef->ddbsymtab, 630 shdr[symtabindex].sh_size, shdr[symtabindex].sh_offset, 631 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, 632 &resid, td); 633 if (error) 634 goto out; 635 if (resid != 0){ 636 error = EINVAL; 637 goto out; 638 } 639 640 if (symstrindex == -1) 641 panic("lost symbol string index"); 642 /* Allocate space for and load the symbol strings */ 643 ef->ddbstrcnt = shdr[symstrindex].sh_size; 644 ef->ddbstrtab = malloc(shdr[symstrindex].sh_size, M_LINKER, M_WAITOK); 645 error = vn_rdwr(UIO_READ, nd.ni_vp, ef->ddbstrtab, 646 shdr[symstrindex].sh_size, shdr[symstrindex].sh_offset, 647 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, 648 &resid, td); 649 if (error) 650 goto out; 651 if (resid != 0){ 652 error = EINVAL; 653 goto out; 654 } 655 656 /* Do we have a string table for the section names? */ 657 shstrindex = -1; 658 if (hdr->e_shstrndx != 0 && 659 shdr[hdr->e_shstrndx].sh_type == SHT_STRTAB) { 660 shstrindex = hdr->e_shstrndx; 661 ef->shstrcnt = shdr[shstrindex].sh_size; 662 ef->shstrtab = malloc(shdr[shstrindex].sh_size, M_LINKER, 663 M_WAITOK); 664 error = vn_rdwr(UIO_READ, nd.ni_vp, ef->shstrtab, 665 shdr[shstrindex].sh_size, shdr[shstrindex].sh_offset, 666 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, 667 &resid, td); 668 if (error) 669 goto out; 670 if (resid != 0){ 671 error = EINVAL; 672 goto out; 673 } 674 } 675 676 /* Size up code/data(progbits) and bss(nobits). */ 677 alignmask = 0; 678 for (i = 0; i < hdr->e_shnum; i++) { 679 if (shdr[i].sh_size == 0) 680 continue; 681 switch (shdr[i].sh_type) { 682 case SHT_PROGBITS: 683 case SHT_NOBITS: 684 alignmask = shdr[i].sh_addralign - 1; 685 mapsize += alignmask; 686 mapsize &= ~alignmask; 687 mapsize += shdr[i].sh_size; 688 break; 689 } 690 } 691 692 /* 693 * We know how much space we need for the text/data/bss/etc. 694 * This stuff needs to be in a single chunk so that profiling etc 695 * can get the bounds and gdb can associate offsets with modules 696 */ 697 ef->object = vm_object_allocate(OBJT_DEFAULT, 698 round_page(mapsize) >> PAGE_SHIFT); 699 if (ef->object == NULL) { 700 error = ENOMEM; 701 goto out; 702 } 703 ef->address = (caddr_t) vm_map_min(kernel_map); 704 705 /* 706 * In order to satisfy amd64's architectural requirements on the 707 * location of code and data in the kernel's address space, request a 708 * mapping that is above the kernel. 709 */ 710 #ifdef __amd64__ 711 mapbase = KERNBASE; 712 #else 713 mapbase = VM_MIN_KERNEL_ADDRESS; 714 #endif 715 error = vm_map_find(kernel_map, ef->object, 0, &mapbase, 716 round_page(mapsize), 0, VMFS_OPTIMAL_SPACE, VM_PROT_ALL, 717 VM_PROT_ALL, 0); 718 if (error) { 719 vm_object_deallocate(ef->object); 720 ef->object = 0; 721 goto out; 722 } 723 724 /* Wire the pages */ 725 error = vm_map_wire(kernel_map, mapbase, 726 mapbase + round_page(mapsize), 727 VM_MAP_WIRE_SYSTEM|VM_MAP_WIRE_NOHOLES); 728 if (error != KERN_SUCCESS) { 729 error = ENOMEM; 730 goto out; 731 } 732 733 /* Inform the kld system about the situation */ 734 lf->address = ef->address = (caddr_t)mapbase; 735 lf->size = mapsize; 736 737 /* 738 * Now load code/data(progbits), zero bss(nobits), allocate space for 739 * and load relocs 740 */ 741 pb = 0; 742 rl = 0; 743 ra = 0; 744 alignmask = 0; 745 for (i = 0; i < hdr->e_shnum; i++) { 746 if (shdr[i].sh_size == 0) 747 continue; 748 switch (shdr[i].sh_type) { 749 case SHT_PROGBITS: 750 case SHT_NOBITS: 751 alignmask = shdr[i].sh_addralign - 1; 752 mapbase += alignmask; 753 mapbase &= ~alignmask; 754 if (ef->shstrtab != NULL && shdr[i].sh_name != 0) { 755 ef->progtab[pb].name = 756 ef->shstrtab + shdr[i].sh_name; 757 if (!strcmp(ef->progtab[pb].name, ".ctors")) { 758 lf->ctors_addr = (caddr_t)mapbase; 759 lf->ctors_size = shdr[i].sh_size; 760 } 761 } else if (shdr[i].sh_type == SHT_PROGBITS) 762 ef->progtab[pb].name = "<<PROGBITS>>"; 763 else 764 ef->progtab[pb].name = "<<NOBITS>>"; 765 if (ef->progtab[pb].name != NULL && 766 !strcmp(ef->progtab[pb].name, DPCPU_SETNAME)) 767 ef->progtab[pb].addr = 768 dpcpu_alloc(shdr[i].sh_size); 769 #ifdef VIMAGE 770 else if (ef->progtab[pb].name != NULL && 771 !strcmp(ef->progtab[pb].name, VNET_SETNAME)) 772 ef->progtab[pb].addr = 773 vnet_data_alloc(shdr[i].sh_size); 774 #endif 775 else 776 ef->progtab[pb].addr = 777 (void *)(uintptr_t)mapbase; 778 if (ef->progtab[pb].addr == NULL) { 779 error = ENOSPC; 780 goto out; 781 } 782 ef->progtab[pb].size = shdr[i].sh_size; 783 ef->progtab[pb].sec = i; 784 if (shdr[i].sh_type == SHT_PROGBITS) { 785 error = vn_rdwr(UIO_READ, nd.ni_vp, 786 ef->progtab[pb].addr, 787 shdr[i].sh_size, shdr[i].sh_offset, 788 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, 789 NOCRED, &resid, td); 790 if (error) 791 goto out; 792 if (resid != 0){ 793 error = EINVAL; 794 goto out; 795 } 796 /* Initialize the per-cpu or vnet area. */ 797 if (ef->progtab[pb].addr != (void *)mapbase && 798 !strcmp(ef->progtab[pb].name, DPCPU_SETNAME)) 799 dpcpu_copy(ef->progtab[pb].addr, 800 shdr[i].sh_size); 801 #ifdef VIMAGE 802 else if (ef->progtab[pb].addr != 803 (void *)mapbase && 804 !strcmp(ef->progtab[pb].name, VNET_SETNAME)) 805 vnet_data_copy(ef->progtab[pb].addr, 806 shdr[i].sh_size); 807 #endif 808 } else 809 bzero(ef->progtab[pb].addr, shdr[i].sh_size); 810 811 /* Update all symbol values with the offset. */ 812 for (j = 0; j < ef->ddbsymcnt; j++) { 813 es = &ef->ddbsymtab[j]; 814 if (es->st_shndx != i) 815 continue; 816 es->st_value += (Elf_Addr)ef->progtab[pb].addr; 817 } 818 mapbase += shdr[i].sh_size; 819 pb++; 820 break; 821 case SHT_REL: 822 ef->reltab[rl].rel = malloc(shdr[i].sh_size, M_LINKER, 823 M_WAITOK); 824 ef->reltab[rl].nrel = shdr[i].sh_size / sizeof(Elf_Rel); 825 ef->reltab[rl].sec = shdr[i].sh_info; 826 error = vn_rdwr(UIO_READ, nd.ni_vp, 827 (void *)ef->reltab[rl].rel, 828 shdr[i].sh_size, shdr[i].sh_offset, 829 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, 830 &resid, td); 831 if (error) 832 goto out; 833 if (resid != 0){ 834 error = EINVAL; 835 goto out; 836 } 837 rl++; 838 break; 839 case SHT_RELA: 840 ef->relatab[ra].rela = malloc(shdr[i].sh_size, M_LINKER, 841 M_WAITOK); 842 ef->relatab[ra].nrela = 843 shdr[i].sh_size / sizeof(Elf_Rela); 844 ef->relatab[ra].sec = shdr[i].sh_info; 845 error = vn_rdwr(UIO_READ, nd.ni_vp, 846 (void *)ef->relatab[ra].rela, 847 shdr[i].sh_size, shdr[i].sh_offset, 848 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED, 849 &resid, td); 850 if (error) 851 goto out; 852 if (resid != 0){ 853 error = EINVAL; 854 goto out; 855 } 856 ra++; 857 break; 858 } 859 } 860 if (pb != ef->nprogtab) 861 panic("lost progbits"); 862 if (rl != ef->nreltab) 863 panic("lost reltab"); 864 if (ra != ef->nrelatab) 865 panic("lost relatab"); 866 if (mapbase != (vm_offset_t)ef->address + mapsize) 867 panic("mapbase 0x%lx != address %p + mapsize 0x%lx (0x%lx)\n", 868 (u_long)mapbase, ef->address, (u_long)mapsize, 869 (u_long)(vm_offset_t)ef->address + mapsize); 870 871 /* Local intra-module relocations */ 872 link_elf_reloc_local(lf); 873 874 /* Pull in dependencies */ 875 VOP_UNLOCK(nd.ni_vp, 0); 876 error = linker_load_dependencies(lf); 877 vn_lock(nd.ni_vp, LK_EXCLUSIVE | LK_RETRY); 878 if (error) 879 goto out; 880 881 /* External relocations */ 882 error = relocate_file(ef); 883 if (error) 884 goto out; 885 886 /* Notify MD code that a module is being loaded. */ 887 error = elf_cpu_load_file(lf); 888 if (error) 889 goto out; 890 891 /* Invoke .ctors */ 892 link_elf_invoke_ctors(lf->ctors_addr, lf->ctors_size); 893 894 *result = lf; 895 896 out: 897 VOP_UNLOCK(nd.ni_vp, 0); 898 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 899 if (error && lf) 900 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 901 if (hdr) 902 free(hdr, M_LINKER); 903 904 return error; 905 } 906 907 static void 908 link_elf_unload_file(linker_file_t file) 909 { 910 elf_file_t ef = (elf_file_t) file; 911 int i; 912 913 /* Notify MD code that a module is being unloaded. */ 914 elf_cpu_unload_file(file); 915 916 if (ef->progtab) { 917 for (i = 0; i < ef->nprogtab; i++) { 918 if (ef->progtab[i].size == 0) 919 continue; 920 if (ef->progtab[i].name == NULL) 921 continue; 922 if (!strcmp(ef->progtab[i].name, DPCPU_SETNAME)) 923 dpcpu_free(ef->progtab[i].addr, 924 ef->progtab[i].size); 925 #ifdef VIMAGE 926 else if (!strcmp(ef->progtab[i].name, VNET_SETNAME)) 927 vnet_data_free(ef->progtab[i].addr, 928 ef->progtab[i].size); 929 #endif 930 } 931 } 932 if (ef->preloaded) { 933 if (ef->reltab) 934 free(ef->reltab, M_LINKER); 935 if (ef->relatab) 936 free(ef->relatab, M_LINKER); 937 if (ef->progtab) 938 free(ef->progtab, M_LINKER); 939 if (ef->ctftab) 940 free(ef->ctftab, M_LINKER); 941 if (ef->ctfoff) 942 free(ef->ctfoff, M_LINKER); 943 if (ef->typoff) 944 free(ef->typoff, M_LINKER); 945 if (file->filename != NULL) 946 preload_delete_name(file->filename); 947 /* XXX reclaim module memory? */ 948 return; 949 } 950 951 for (i = 0; i < ef->nreltab; i++) 952 if (ef->reltab[i].rel) 953 free(ef->reltab[i].rel, M_LINKER); 954 for (i = 0; i < ef->nrelatab; i++) 955 if (ef->relatab[i].rela) 956 free(ef->relatab[i].rela, M_LINKER); 957 if (ef->reltab) 958 free(ef->reltab, M_LINKER); 959 if (ef->relatab) 960 free(ef->relatab, M_LINKER); 961 if (ef->progtab) 962 free(ef->progtab, M_LINKER); 963 964 if (ef->object) { 965 vm_map_remove(kernel_map, (vm_offset_t) ef->address, 966 (vm_offset_t) ef->address + 967 (ef->object->size << PAGE_SHIFT)); 968 } 969 if (ef->e_shdr) 970 free(ef->e_shdr, M_LINKER); 971 if (ef->ddbsymtab) 972 free(ef->ddbsymtab, M_LINKER); 973 if (ef->ddbstrtab) 974 free(ef->ddbstrtab, M_LINKER); 975 if (ef->shstrtab) 976 free(ef->shstrtab, M_LINKER); 977 if (ef->ctftab) 978 free(ef->ctftab, M_LINKER); 979 if (ef->ctfoff) 980 free(ef->ctfoff, M_LINKER); 981 if (ef->typoff) 982 free(ef->typoff, M_LINKER); 983 } 984 985 static const char * 986 symbol_name(elf_file_t ef, Elf_Size r_info) 987 { 988 const Elf_Sym *ref; 989 990 if (ELF_R_SYM(r_info)) { 991 ref = ef->ddbsymtab + ELF_R_SYM(r_info); 992 return ef->ddbstrtab + ref->st_name; 993 } else 994 return NULL; 995 } 996 997 static Elf_Addr 998 findbase(elf_file_t ef, int sec) 999 { 1000 int i; 1001 Elf_Addr base = 0; 1002 1003 for (i = 0; i < ef->nprogtab; i++) { 1004 if (sec == ef->progtab[i].sec) { 1005 base = (Elf_Addr)ef->progtab[i].addr; 1006 break; 1007 } 1008 } 1009 return base; 1010 } 1011 1012 static int 1013 relocate_file(elf_file_t ef) 1014 { 1015 const Elf_Rel *rellim; 1016 const Elf_Rel *rel; 1017 const Elf_Rela *relalim; 1018 const Elf_Rela *rela; 1019 const char *symname; 1020 const Elf_Sym *sym; 1021 int i; 1022 Elf_Size symidx; 1023 Elf_Addr base; 1024 1025 1026 /* Perform relocations without addend if there are any: */ 1027 for (i = 0; i < ef->nreltab; i++) { 1028 rel = ef->reltab[i].rel; 1029 if (rel == NULL) 1030 panic("lost a reltab!"); 1031 rellim = rel + ef->reltab[i].nrel; 1032 base = findbase(ef, ef->reltab[i].sec); 1033 if (base == 0) 1034 panic("lost base for reltab"); 1035 for ( ; rel < rellim; rel++) { 1036 symidx = ELF_R_SYM(rel->r_info); 1037 if (symidx >= ef->ddbsymcnt) 1038 continue; 1039 sym = ef->ddbsymtab + symidx; 1040 /* Local relocs are already done */ 1041 if (ELF_ST_BIND(sym->st_info) == STB_LOCAL) 1042 continue; 1043 if (elf_reloc(&ef->lf, base, rel, ELF_RELOC_REL, 1044 elf_obj_lookup)) { 1045 symname = symbol_name(ef, rel->r_info); 1046 printf("link_elf_obj: symbol %s undefined\n", 1047 symname); 1048 return ENOENT; 1049 } 1050 } 1051 } 1052 1053 /* Perform relocations with addend if there are any: */ 1054 for (i = 0; i < ef->nrelatab; i++) { 1055 rela = ef->relatab[i].rela; 1056 if (rela == NULL) 1057 panic("lost a relatab!"); 1058 relalim = rela + ef->relatab[i].nrela; 1059 base = findbase(ef, ef->relatab[i].sec); 1060 if (base == 0) 1061 panic("lost base for relatab"); 1062 for ( ; rela < relalim; rela++) { 1063 symidx = ELF_R_SYM(rela->r_info); 1064 if (symidx >= ef->ddbsymcnt) 1065 continue; 1066 sym = ef->ddbsymtab + symidx; 1067 /* Local relocs are already done */ 1068 if (ELF_ST_BIND(sym->st_info) == STB_LOCAL) 1069 continue; 1070 if (elf_reloc(&ef->lf, base, rela, ELF_RELOC_RELA, 1071 elf_obj_lookup)) { 1072 symname = symbol_name(ef, rela->r_info); 1073 printf("link_elf_obj: symbol %s undefined\n", 1074 symname); 1075 return ENOENT; 1076 } 1077 } 1078 } 1079 1080 /* 1081 * Only clean SHN_FBSD_CACHED for successfull return. If we 1082 * modified symbol table for the object but found an 1083 * unresolved symbol, there is no reason to roll back. 1084 */ 1085 elf_obj_cleanup_globals_cache(ef); 1086 1087 return 0; 1088 } 1089 1090 static int 1091 link_elf_lookup_symbol(linker_file_t lf, const char *name, c_linker_sym_t *sym) 1092 { 1093 elf_file_t ef = (elf_file_t) lf; 1094 const Elf_Sym *symp; 1095 const char *strp; 1096 int i; 1097 1098 for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) { 1099 strp = ef->ddbstrtab + symp->st_name; 1100 if (symp->st_shndx != SHN_UNDEF && strcmp(name, strp) == 0) { 1101 *sym = (c_linker_sym_t) symp; 1102 return 0; 1103 } 1104 } 1105 return ENOENT; 1106 } 1107 1108 static int 1109 link_elf_symbol_values(linker_file_t lf, c_linker_sym_t sym, 1110 linker_symval_t *symval) 1111 { 1112 elf_file_t ef = (elf_file_t) lf; 1113 const Elf_Sym *es = (const Elf_Sym*) sym; 1114 1115 if (es >= ef->ddbsymtab && es < (ef->ddbsymtab + ef->ddbsymcnt)) { 1116 symval->name = ef->ddbstrtab + es->st_name; 1117 symval->value = (caddr_t)es->st_value; 1118 symval->size = es->st_size; 1119 return 0; 1120 } 1121 return ENOENT; 1122 } 1123 1124 static int 1125 link_elf_search_symbol(linker_file_t lf, caddr_t value, 1126 c_linker_sym_t *sym, long *diffp) 1127 { 1128 elf_file_t ef = (elf_file_t) lf; 1129 u_long off = (uintptr_t) (void *) value; 1130 u_long diff = off; 1131 u_long st_value; 1132 const Elf_Sym *es; 1133 const Elf_Sym *best = 0; 1134 int i; 1135 1136 for (i = 0, es = ef->ddbsymtab; i < ef->ddbsymcnt; i++, es++) { 1137 if (es->st_name == 0) 1138 continue; 1139 st_value = es->st_value; 1140 if (off >= st_value) { 1141 if (off - st_value < diff) { 1142 diff = off - st_value; 1143 best = es; 1144 if (diff == 0) 1145 break; 1146 } else if (off - st_value == diff) { 1147 best = es; 1148 } 1149 } 1150 } 1151 if (best == 0) 1152 *diffp = off; 1153 else 1154 *diffp = diff; 1155 *sym = (c_linker_sym_t) best; 1156 1157 return 0; 1158 } 1159 1160 /* 1161 * Look up a linker set on an ELF system. 1162 */ 1163 static int 1164 link_elf_lookup_set(linker_file_t lf, const char *name, 1165 void ***startp, void ***stopp, int *countp) 1166 { 1167 elf_file_t ef = (elf_file_t)lf; 1168 void **start, **stop; 1169 int i, count; 1170 1171 /* Relative to section number */ 1172 for (i = 0; i < ef->nprogtab; i++) { 1173 if ((strncmp(ef->progtab[i].name, "set_", 4) == 0) && 1174 strcmp(ef->progtab[i].name + 4, name) == 0) { 1175 start = (void **)ef->progtab[i].addr; 1176 stop = (void **)((char *)ef->progtab[i].addr + 1177 ef->progtab[i].size); 1178 count = stop - start; 1179 if (startp) 1180 *startp = start; 1181 if (stopp) 1182 *stopp = stop; 1183 if (countp) 1184 *countp = count; 1185 return (0); 1186 } 1187 } 1188 return (ESRCH); 1189 } 1190 1191 static int 1192 link_elf_each_function_name(linker_file_t file, 1193 int (*callback)(const char *, void *), void *opaque) 1194 { 1195 elf_file_t ef = (elf_file_t)file; 1196 const Elf_Sym *symp; 1197 int i, error; 1198 1199 /* Exhaustive search */ 1200 for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) { 1201 if (symp->st_value != 0 && 1202 ELF_ST_TYPE(symp->st_info) == STT_FUNC) { 1203 error = callback(ef->ddbstrtab + symp->st_name, opaque); 1204 if (error) 1205 return (error); 1206 } 1207 } 1208 return (0); 1209 } 1210 1211 static int 1212 link_elf_each_function_nameval(linker_file_t file, 1213 linker_function_nameval_callback_t callback, void *opaque) 1214 { 1215 linker_symval_t symval; 1216 elf_file_t ef = (elf_file_t)file; 1217 const Elf_Sym* symp; 1218 int i, error; 1219 1220 /* Exhaustive search */ 1221 for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) { 1222 if (symp->st_value != 0 && 1223 ELF_ST_TYPE(symp->st_info) == STT_FUNC) { 1224 error = link_elf_symbol_values(file, (c_linker_sym_t) symp, &symval); 1225 if (error) 1226 return (error); 1227 error = callback(file, i, &symval, opaque); 1228 if (error) 1229 return (error); 1230 } 1231 } 1232 return (0); 1233 } 1234 1235 static void 1236 elf_obj_cleanup_globals_cache(elf_file_t ef) 1237 { 1238 Elf_Sym *sym; 1239 Elf_Size i; 1240 1241 for (i = 0; i < ef->ddbsymcnt; i++) { 1242 sym = ef->ddbsymtab + i; 1243 if (sym->st_shndx == SHN_FBSD_CACHED) { 1244 sym->st_shndx = SHN_UNDEF; 1245 sym->st_value = 0; 1246 } 1247 } 1248 } 1249 1250 /* 1251 * Symbol lookup function that can be used when the symbol index is known (ie 1252 * in relocations). It uses the symbol index instead of doing a fully fledged 1253 * hash table based lookup when such is valid. For example for local symbols. 1254 * This is not only more efficient, it's also more correct. It's not always 1255 * the case that the symbol can be found through the hash table. 1256 */ 1257 static int 1258 elf_obj_lookup(linker_file_t lf, Elf_Size symidx, int deps, Elf_Addr *res) 1259 { 1260 elf_file_t ef = (elf_file_t)lf; 1261 Elf_Sym *sym; 1262 const char *symbol; 1263 Elf_Addr res1; 1264 1265 /* Don't even try to lookup the symbol if the index is bogus. */ 1266 if (symidx >= ef->ddbsymcnt) { 1267 *res = 0; 1268 return (EINVAL); 1269 } 1270 1271 sym = ef->ddbsymtab + symidx; 1272 1273 /* Quick answer if there is a definition included. */ 1274 if (sym->st_shndx != SHN_UNDEF) { 1275 *res = sym->st_value; 1276 return (0); 1277 } 1278 1279 /* If we get here, then it is undefined and needs a lookup. */ 1280 switch (ELF_ST_BIND(sym->st_info)) { 1281 case STB_LOCAL: 1282 /* Local, but undefined? huh? */ 1283 *res = 0; 1284 return (EINVAL); 1285 1286 case STB_GLOBAL: 1287 case STB_WEAK: 1288 /* Relative to Data or Function name */ 1289 symbol = ef->ddbstrtab + sym->st_name; 1290 1291 /* Force a lookup failure if the symbol name is bogus. */ 1292 if (*symbol == 0) { 1293 *res = 0; 1294 return (EINVAL); 1295 } 1296 res1 = (Elf_Addr)linker_file_lookup_symbol(lf, symbol, deps); 1297 1298 /* 1299 * Cache global lookups during module relocation. The failure 1300 * case is particularly expensive for callers, who must scan 1301 * through the entire globals table doing strcmp(). Cache to 1302 * avoid doing such work repeatedly. 1303 * 1304 * After relocation is complete, undefined globals will be 1305 * restored to SHN_UNDEF in elf_obj_cleanup_globals_cache(), 1306 * above. 1307 */ 1308 if (res1 != 0) { 1309 sym->st_shndx = SHN_FBSD_CACHED; 1310 sym->st_value = res1; 1311 *res = res1; 1312 return (0); 1313 } else if (ELF_ST_BIND(sym->st_info) == STB_WEAK) { 1314 sym->st_value = 0; 1315 *res = 0; 1316 return (0); 1317 } 1318 return (EINVAL); 1319 1320 default: 1321 return (EINVAL); 1322 } 1323 } 1324 1325 static void 1326 link_elf_fix_link_set(elf_file_t ef) 1327 { 1328 static const char startn[] = "__start_"; 1329 static const char stopn[] = "__stop_"; 1330 Elf_Sym *sym; 1331 const char *sym_name, *linkset_name; 1332 Elf_Addr startp, stopp; 1333 Elf_Size symidx; 1334 int start, i; 1335 1336 startp = stopp = 0; 1337 for (symidx = 1 /* zero entry is special */; 1338 symidx < ef->ddbsymcnt; symidx++) { 1339 sym = ef->ddbsymtab + symidx; 1340 if (sym->st_shndx != SHN_UNDEF) 1341 continue; 1342 1343 sym_name = ef->ddbstrtab + sym->st_name; 1344 if (strncmp(sym_name, startn, sizeof(startn) - 1) == 0) { 1345 start = 1; 1346 linkset_name = sym_name + sizeof(startn) - 1; 1347 } 1348 else if (strncmp(sym_name, stopn, sizeof(stopn) - 1) == 0) { 1349 start = 0; 1350 linkset_name = sym_name + sizeof(stopn) - 1; 1351 } 1352 else 1353 continue; 1354 1355 for (i = 0; i < ef->nprogtab; i++) { 1356 if (strcmp(ef->progtab[i].name, linkset_name) == 0) { 1357 startp = (Elf_Addr)ef->progtab[i].addr; 1358 stopp = (Elf_Addr)(startp + ef->progtab[i].size); 1359 break; 1360 } 1361 } 1362 if (i == ef->nprogtab) 1363 continue; 1364 1365 sym->st_value = start ? startp : stopp; 1366 sym->st_shndx = i; 1367 } 1368 } 1369 1370 static void 1371 link_elf_reloc_local(linker_file_t lf) 1372 { 1373 elf_file_t ef = (elf_file_t)lf; 1374 const Elf_Rel *rellim; 1375 const Elf_Rel *rel; 1376 const Elf_Rela *relalim; 1377 const Elf_Rela *rela; 1378 const Elf_Sym *sym; 1379 Elf_Addr base; 1380 int i; 1381 Elf_Size symidx; 1382 1383 link_elf_fix_link_set(ef); 1384 1385 /* Perform relocations without addend if there are any: */ 1386 for (i = 0; i < ef->nreltab; i++) { 1387 rel = ef->reltab[i].rel; 1388 if (rel == NULL) 1389 panic("lost a reltab!"); 1390 rellim = rel + ef->reltab[i].nrel; 1391 base = findbase(ef, ef->reltab[i].sec); 1392 if (base == 0) 1393 panic("lost base for reltab"); 1394 for ( ; rel < rellim; rel++) { 1395 symidx = ELF_R_SYM(rel->r_info); 1396 if (symidx >= ef->ddbsymcnt) 1397 continue; 1398 sym = ef->ddbsymtab + symidx; 1399 /* Only do local relocs */ 1400 if (ELF_ST_BIND(sym->st_info) != STB_LOCAL) 1401 continue; 1402 elf_reloc_local(lf, base, rel, ELF_RELOC_REL, 1403 elf_obj_lookup); 1404 } 1405 } 1406 1407 /* Perform relocations with addend if there are any: */ 1408 for (i = 0; i < ef->nrelatab; i++) { 1409 rela = ef->relatab[i].rela; 1410 if (rela == NULL) 1411 panic("lost a relatab!"); 1412 relalim = rela + ef->relatab[i].nrela; 1413 base = findbase(ef, ef->relatab[i].sec); 1414 if (base == 0) 1415 panic("lost base for relatab"); 1416 for ( ; rela < relalim; rela++) { 1417 symidx = ELF_R_SYM(rela->r_info); 1418 if (symidx >= ef->ddbsymcnt) 1419 continue; 1420 sym = ef->ddbsymtab + symidx; 1421 /* Only do local relocs */ 1422 if (ELF_ST_BIND(sym->st_info) != STB_LOCAL) 1423 continue; 1424 elf_reloc_local(lf, base, rela, ELF_RELOC_RELA, 1425 elf_obj_lookup); 1426 } 1427 } 1428 } 1429 1430 static long 1431 link_elf_symtab_get(linker_file_t lf, const Elf_Sym **symtab) 1432 { 1433 elf_file_t ef = (elf_file_t)lf; 1434 1435 *symtab = ef->ddbsymtab; 1436 1437 if (*symtab == NULL) 1438 return (0); 1439 1440 return (ef->ddbsymcnt); 1441 } 1442 1443 static long 1444 link_elf_strtab_get(linker_file_t lf, caddr_t *strtab) 1445 { 1446 elf_file_t ef = (elf_file_t)lf; 1447 1448 *strtab = ef->ddbstrtab; 1449 1450 if (*strtab == NULL) 1451 return (0); 1452 1453 return (ef->ddbstrcnt); 1454 } 1455