Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)
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FreeBSD/Linux Kernel Cross Reference
sys/kern/kern_linker.c
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1 /*- 2 * Copyright (c) 1997-2000 Doug Rabson 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $FreeBSD: releng/5.0/sys/kern/kern_linker.c 108086 2002-12-19 09:40:13Z alfred $ 27 */ 28 29 #include "opt_ddb.h" 30 #include "opt_mac.h" 31 32 #include <sys/param.h> 33 #include <sys/kernel.h> 34 #include <sys/systm.h> 35 #include <sys/malloc.h> 36 #include <sys/sysproto.h> 37 #include <sys/sysent.h> 38 #include <sys/proc.h> 39 #include <sys/lock.h> 40 #include <sys/mutex.h> 41 #include <sys/sx.h> 42 #include <sys/mac.h> 43 #include <sys/module.h> 44 #include <sys/linker.h> 45 #include <sys/fcntl.h> 46 #include <sys/libkern.h> 47 #include <sys/namei.h> 48 #include <sys/vnode.h> 49 #include <sys/sysctl.h> 50 51 #include "linker_if.h" 52 53 #ifdef KLD_DEBUG 54 int kld_debug = 0; 55 #endif 56 57 /* 58 * static char *linker_search_path(const char *name, struct mod_depend 59 * *verinfo); 60 */ 61 static const char *linker_basename(const char *path); 62 63 /* Metadata from the static kernel */ 64 SET_DECLARE(modmetadata_set, struct mod_metadata); 65 66 MALLOC_DEFINE(M_LINKER, "linker", "kernel linker"); 67 68 linker_file_t linker_kernel_file; 69 70 static struct mtx kld_mtx; /* kernel linker mutex */ 71 72 static linker_class_list_t classes; 73 static linker_file_list_t linker_files; 74 static int next_file_id = 1; 75 static int linker_no_more_classes = 0; 76 77 #define LINKER_GET_NEXT_FILE_ID(a) do { \ 78 linker_file_t lftmp; \ 79 \ 80 retry: \ 81 mtx_lock(&kld_mtx); \ 82 TAILQ_FOREACH(lftmp, &linker_files, link) { \ 83 if (next_file_id == lftmp->id) { \ 84 next_file_id++; \ 85 mtx_unlock(&kld_mtx); \ 86 goto retry; \ 87 } \ 88 } \ 89 (a) = next_file_id; \ 90 mtx_unlock(&kld_mtx); /* Hold for safe read of id variable */ \ 91 } while(0) 92 93 94 /* XXX wrong name; we're looking at version provision tags here, not modules */ 95 typedef TAILQ_HEAD(, modlist) modlisthead_t; 96 struct modlist { 97 TAILQ_ENTRY(modlist) link; /* chain together all modules */ 98 linker_file_t container; 99 const char *name; 100 int version; 101 }; 102 typedef struct modlist *modlist_t; 103 static modlisthead_t found_modules; 104 105 static modlist_t modlist_lookup2(const char *name, 106 struct mod_depend *verinfo); 107 108 static char * 109 linker_strdup(const char *str) 110 { 111 char *result; 112 113 if ((result = malloc((strlen(str) + 1), M_LINKER, M_WAITOK)) != NULL) 114 strcpy(result, str); 115 return (result); 116 } 117 118 static void 119 linker_init(void *arg) 120 { 121 122 mtx_init(&kld_mtx, "kernel linker", NULL, MTX_DEF); 123 TAILQ_INIT(&classes); 124 TAILQ_INIT(&linker_files); 125 } 126 127 SYSINIT(linker, SI_SUB_KLD, SI_ORDER_FIRST, linker_init, 0) 128 129 static void 130 linker_stop_class_add(void *arg) 131 { 132 133 linker_no_more_classes = 1; 134 } 135 136 SYSINIT(linker_class, SI_SUB_KLD, SI_ORDER_ANY, linker_stop_class_add, NULL) 137 138 int 139 linker_add_class(linker_class_t lc) 140 { 141 142 /* 143 * We disallow any class registration passt SI_ORDER_ANY 144 * of SI_SUB_KLD. 145 */ 146 if (linker_no_more_classes == 1) 147 return (EPERM); 148 kobj_class_compile((kobj_class_t) lc); 149 TAILQ_INSERT_TAIL(&classes, lc, link); 150 return (0); 151 } 152 153 static void 154 linker_file_sysinit(linker_file_t lf) 155 { 156 struct sysinit **start, **stop, **sipp, **xipp, *save; 157 158 KLD_DPF(FILE, ("linker_file_sysinit: calling SYSINITs for %s\n", 159 lf->filename)); 160 161 if (linker_file_lookup_set(lf, "sysinit_set", &start, &stop, NULL) != 0) 162 return; 163 /* 164 * Perform a bubble sort of the system initialization objects by 165 * their subsystem (primary key) and order (secondary key). 166 * 167 * Since some things care about execution order, this is the operation 168 * which ensures continued function. 169 */ 170 for (sipp = start; sipp < stop; sipp++) { 171 for (xipp = sipp + 1; xipp < stop; xipp++) { 172 if ((*sipp)->subsystem < (*xipp)->subsystem || 173 ((*sipp)->subsystem == (*xipp)->subsystem && 174 (*sipp)->order <= (*xipp)->order)) 175 continue; /* skip */ 176 save = *sipp; 177 *sipp = *xipp; 178 *xipp = save; 179 } 180 } 181 182 /* 183 * Traverse the (now) ordered list of system initialization tasks. 184 * Perform each task, and continue on to the next task. 185 */ 186 for (sipp = start; sipp < stop; sipp++) { 187 if ((*sipp)->subsystem == SI_SUB_DUMMY) 188 continue; /* skip dummy task(s) */ 189 190 /* Call function */ 191 (*((*sipp)->func)) ((*sipp)->udata); 192 } 193 } 194 195 static void 196 linker_file_sysuninit(linker_file_t lf) 197 { 198 struct sysinit **start, **stop, **sipp, **xipp, *save; 199 200 KLD_DPF(FILE, ("linker_file_sysuninit: calling SYSUNINITs for %s\n", 201 lf->filename)); 202 203 if (linker_file_lookup_set(lf, "sysuninit_set", &start, &stop, 204 NULL) != 0) 205 return; 206 207 /* 208 * Perform a reverse bubble sort of the system initialization objects 209 * by their subsystem (primary key) and order (secondary key). 210 * 211 * Since some things care about execution order, this is the operation 212 * which ensures continued function. 213 */ 214 for (sipp = start; sipp < stop; sipp++) { 215 for (xipp = sipp + 1; xipp < stop; xipp++) { 216 if ((*sipp)->subsystem > (*xipp)->subsystem || 217 ((*sipp)->subsystem == (*xipp)->subsystem && 218 (*sipp)->order >= (*xipp)->order)) 219 continue; /* skip */ 220 save = *sipp; 221 *sipp = *xipp; 222 *xipp = save; 223 } 224 } 225 226 /* 227 * Traverse the (now) ordered list of system initialization tasks. 228 * Perform each task, and continue on to the next task. 229 */ 230 for (sipp = start; sipp < stop; sipp++) { 231 if ((*sipp)->subsystem == SI_SUB_DUMMY) 232 continue; /* skip dummy task(s) */ 233 234 /* Call function */ 235 (*((*sipp)->func)) ((*sipp)->udata); 236 } 237 } 238 239 static void 240 linker_file_register_sysctls(linker_file_t lf) 241 { 242 struct sysctl_oid **start, **stop, **oidp; 243 244 KLD_DPF(FILE, 245 ("linker_file_register_sysctls: registering SYSCTLs for %s\n", 246 lf->filename)); 247 248 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0) 249 return; 250 251 for (oidp = start; oidp < stop; oidp++) 252 sysctl_register_oid(*oidp); 253 } 254 255 static void 256 linker_file_unregister_sysctls(linker_file_t lf) 257 { 258 struct sysctl_oid **start, **stop, **oidp; 259 260 KLD_DPF(FILE, ("linker_file_unregister_sysctls: registering SYSCTLs" 261 " for %s\n", lf->filename)); 262 263 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0) 264 return; 265 266 for (oidp = start; oidp < stop; oidp++) 267 sysctl_unregister_oid(*oidp); 268 } 269 270 static int 271 linker_file_register_modules(linker_file_t lf) 272 { 273 struct mod_metadata **start, **stop, **mdp; 274 const moduledata_t *moddata; 275 int error; 276 277 KLD_DPF(FILE, ("linker_file_register_modules: registering modules" 278 " in %s\n", lf->filename)); 279 280 if (linker_file_lookup_set(lf, "modmetadata_set", &start, 281 &stop, 0) != 0) { 282 /* 283 * This fallback should be unnecessary, but if we get booted 284 * from boot2 instead of loader and we are missing our 285 * metadata then we have to try the best we can. 286 */ 287 if (lf == linker_kernel_file) { 288 start = SET_BEGIN(modmetadata_set); 289 stop = SET_LIMIT(modmetadata_set); 290 } else 291 return (0); 292 } 293 for (mdp = start; mdp < stop; mdp++) { 294 if ((*mdp)->md_type != MDT_MODULE) 295 continue; 296 moddata = (*mdp)->md_data; 297 KLD_DPF(FILE, ("Registering module %s in %s\n", 298 moddata->name, lf->filename)); 299 error = module_register(moddata, lf); 300 if (error) 301 printf("Module %s failed to register: %d\n", 302 moddata->name, error); 303 } 304 return (0); 305 } 306 307 static void 308 linker_init_kernel_modules(void) 309 { 310 311 linker_file_register_modules(linker_kernel_file); 312 } 313 314 SYSINIT(linker_kernel, SI_SUB_KLD, SI_ORDER_ANY, linker_init_kernel_modules, 0) 315 316 static int 317 linker_load_file(const char *filename, linker_file_t *result) 318 { 319 linker_class_t lc; 320 linker_file_t lf; 321 int foundfile, error = 0; 322 323 /* Refuse to load modules if securelevel raised */ 324 if (securelevel > 0) 325 return (EPERM); 326 327 lf = linker_find_file_by_name(filename); 328 if (lf) { 329 KLD_DPF(FILE, ("linker_load_file: file %s is already loaded," 330 " incrementing refs\n", filename)); 331 *result = lf; 332 lf->refs++; 333 goto out; 334 } 335 lf = NULL; 336 foundfile = 0; 337 338 /* 339 * We do not need to protect (lock) classes here because there is 340 * no class registration past startup (SI_SUB_KLD, SI_ORDER_ANY) 341 * and there is no class deregistration mechanism at this time. 342 */ 343 TAILQ_FOREACH(lc, &classes, link) { 344 KLD_DPF(FILE, ("linker_load_file: trying to load %s\n", 345 filename)); 346 error = LINKER_LOAD_FILE(lc, filename, &lf); 347 /* 348 * If we got something other than ENOENT, then it exists but 349 * we cannot load it for some other reason. 350 */ 351 if (error != ENOENT) 352 foundfile = 1; 353 if (lf) { 354 linker_file_register_modules(lf); 355 linker_file_register_sysctls(lf); 356 linker_file_sysinit(lf); 357 lf->flags |= LINKER_FILE_LINKED; 358 *result = lf; 359 error = 0; 360 goto out; 361 } 362 } 363 /* 364 * Less than ideal, but tells the user whether it failed to load or 365 * the module was not found. 366 */ 367 if (foundfile) { 368 /* 369 * Format not recognized or otherwise unloadable. 370 * When loading a module that is statically built into 371 * the kernel EEXIST percolates back up as the return 372 * value. Preserve this so that apps like sysinstall 373 * can recognize this special case and not post bogus 374 * dialog boxes. 375 */ 376 if (error != EEXIST) 377 error = ENOEXEC; 378 } else 379 error = ENOENT; /* Nothing found */ 380 out: 381 return (error); 382 } 383 384 int 385 linker_reference_module(const char *modname, struct mod_depend *verinfo, 386 linker_file_t *result) 387 { 388 modlist_t mod; 389 390 if ((mod = modlist_lookup2(modname, verinfo)) != NULL) { 391 *result = mod->container; 392 (*result)->refs++; 393 return (0); 394 } 395 396 return (linker_load_module(NULL, modname, NULL, verinfo, result)); 397 } 398 399 linker_file_t 400 linker_find_file_by_name(const char *filename) 401 { 402 linker_file_t lf = 0; 403 char *koname; 404 405 koname = malloc(strlen(filename) + 4, M_LINKER, M_WAITOK); 406 if (koname == NULL) 407 goto out; 408 sprintf(koname, "%s.ko", filename); 409 410 mtx_lock(&kld_mtx); 411 TAILQ_FOREACH(lf, &linker_files, link) { 412 if (strcmp(lf->filename, koname) == 0) 413 break; 414 if (strcmp(lf->filename, filename) == 0) 415 break; 416 } 417 mtx_unlock(&kld_mtx); 418 out: 419 if (koname) 420 free(koname, M_LINKER); 421 return (lf); 422 } 423 424 linker_file_t 425 linker_find_file_by_id(int fileid) 426 { 427 linker_file_t lf = 0; 428 429 mtx_lock(&kld_mtx); 430 TAILQ_FOREACH(lf, &linker_files, link) 431 if (lf->id == fileid) 432 break; 433 mtx_unlock(&kld_mtx); 434 return (lf); 435 } 436 437 linker_file_t 438 linker_make_file(const char *pathname, linker_class_t lc) 439 { 440 linker_file_t lf; 441 const char *filename; 442 443 lf = NULL; 444 filename = linker_basename(pathname); 445 446 KLD_DPF(FILE, ("linker_make_file: new file, filename=%s\n", filename)); 447 lf = (linker_file_t)kobj_create((kobj_class_t)lc, M_LINKER, M_WAITOK); 448 if (lf == NULL) 449 goto out; 450 lf->refs = 1; 451 lf->userrefs = 0; 452 lf->flags = 0; 453 lf->filename = linker_strdup(filename); 454 LINKER_GET_NEXT_FILE_ID(lf->id); 455 lf->ndeps = 0; 456 lf->deps = NULL; 457 STAILQ_INIT(&lf->common); 458 TAILQ_INIT(&lf->modules); 459 mtx_lock(&kld_mtx); 460 TAILQ_INSERT_TAIL(&linker_files, lf, link); 461 mtx_unlock(&kld_mtx); 462 out: 463 return (lf); 464 } 465 466 int 467 linker_file_unload(linker_file_t file) 468 { 469 module_t mod, next; 470 modlist_t ml, nextml; 471 struct common_symbol *cp; 472 int error, i; 473 474 error = 0; 475 476 /* Refuse to unload modules if securelevel raised. */ 477 if (securelevel > 0) 478 return (EPERM); 479 #ifdef MAC 480 error = mac_check_kld_unload(curthread->td_ucred); 481 if (error) 482 return (error); 483 #endif 484 485 KLD_DPF(FILE, ("linker_file_unload: lf->refs=%d\n", file->refs)); 486 if (file->refs == 1) { 487 KLD_DPF(FILE, ("linker_file_unload: file is unloading," 488 " informing modules\n")); 489 490 /* 491 * Inform any modules associated with this file. 492 */ 493 MOD_XLOCK; 494 for (mod = TAILQ_FIRST(&file->modules); mod; mod = next) { 495 next = module_getfnext(mod); 496 MOD_XUNLOCK; 497 498 /* 499 * Give the module a chance to veto the unload. 500 */ 501 if ((error = module_unload(mod)) != 0) { 502 KLD_DPF(FILE, ("linker_file_unload: module %x" 503 " vetoes unload\n", mod)); 504 goto out; 505 } else 506 MOD_XLOCK; 507 module_release(mod); 508 } 509 MOD_XUNLOCK; 510 } 511 file->refs--; 512 if (file->refs > 0) { 513 goto out; 514 } 515 for (ml = TAILQ_FIRST(&found_modules); ml; ml = nextml) { 516 nextml = TAILQ_NEXT(ml, link); 517 if (ml->container == file) 518 TAILQ_REMOVE(&found_modules, ml, link); 519 } 520 521 /* 522 * Don't try to run SYSUNINITs if we are unloaded due to a 523 * link error. 524 */ 525 if (file->flags & LINKER_FILE_LINKED) { 526 linker_file_sysuninit(file); 527 linker_file_unregister_sysctls(file); 528 } 529 mtx_lock(&kld_mtx); 530 TAILQ_REMOVE(&linker_files, file, link); 531 mtx_unlock(&kld_mtx); 532 533 if (file->deps) { 534 for (i = 0; i < file->ndeps; i++) 535 linker_file_unload(file->deps[i]); 536 free(file->deps, M_LINKER); 537 file->deps = NULL; 538 } 539 for (cp = STAILQ_FIRST(&file->common); cp; 540 cp = STAILQ_FIRST(&file->common)) { 541 STAILQ_REMOVE(&file->common, cp, common_symbol, link); 542 free(cp, M_LINKER); 543 } 544 545 LINKER_UNLOAD(file); 546 if (file->filename) { 547 free(file->filename, M_LINKER); 548 file->filename = NULL; 549 } 550 kobj_delete((kobj_t) file, M_LINKER); 551 out: 552 return (error); 553 } 554 555 int 556 linker_file_add_dependency(linker_file_t file, linker_file_t dep) 557 { 558 linker_file_t *newdeps; 559 560 newdeps = malloc((file->ndeps + 1) * sizeof(linker_file_t *), 561 M_LINKER, M_WAITOK | M_ZERO); 562 if (newdeps == NULL) 563 return (ENOMEM); 564 565 if (file->deps) { 566 bcopy(file->deps, newdeps, 567 file->ndeps * sizeof(linker_file_t *)); 568 free(file->deps, M_LINKER); 569 } 570 file->deps = newdeps; 571 file->deps[file->ndeps] = dep; 572 file->ndeps++; 573 return (0); 574 } 575 576 /* 577 * Locate a linker set and its contents. This is a helper function to avoid 578 * linker_if.h exposure elsewhere. Note: firstp and lastp are really void *** 579 */ 580 int 581 linker_file_lookup_set(linker_file_t file, const char *name, 582 void *firstp, void *lastp, int *countp) 583 { 584 585 return (LINKER_LOOKUP_SET(file, name, firstp, lastp, countp)); 586 } 587 588 caddr_t 589 linker_file_lookup_symbol(linker_file_t file, const char *name, int deps) 590 { 591 c_linker_sym_t sym; 592 linker_symval_t symval; 593 caddr_t address; 594 size_t common_size = 0; 595 int i; 596 597 KLD_DPF(SYM, ("linker_file_lookup_symbol: file=%x, name=%s, deps=%d\n", 598 file, name, deps)); 599 600 if (LINKER_LOOKUP_SYMBOL(file, name, &sym) == 0) { 601 LINKER_SYMBOL_VALUES(file, sym, &symval); 602 if (symval.value == 0) 603 /* 604 * For commons, first look them up in the 605 * dependencies and only allocate space if not found 606 * there. 607 */ 608 common_size = symval.size; 609 else { 610 KLD_DPF(SYM, ("linker_file_lookup_symbol: symbol" 611 ".value=%x\n", symval.value)); 612 return (symval.value); 613 } 614 } 615 if (deps) { 616 for (i = 0; i < file->ndeps; i++) { 617 address = linker_file_lookup_symbol(file->deps[i], 618 name, 0); 619 if (address) { 620 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 621 " deps value=%x\n", address)); 622 return (address); 623 } 624 } 625 } 626 if (common_size > 0) { 627 /* 628 * This is a common symbol which was not found in the 629 * dependencies. We maintain a simple common symbol table in 630 * the file object. 631 */ 632 struct common_symbol *cp; 633 634 STAILQ_FOREACH(cp, &file->common, link) { 635 if (strcmp(cp->name, name) == 0) { 636 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 637 " old common value=%x\n", cp->address)); 638 return (cp->address); 639 } 640 } 641 /* 642 * Round the symbol size up to align. 643 */ 644 common_size = (common_size + sizeof(int) - 1) & -sizeof(int); 645 cp = malloc(sizeof(struct common_symbol) 646 + common_size + strlen(name) + 1, M_LINKER, 647 M_WAITOK | M_ZERO); 648 if (cp == NULL) { 649 KLD_DPF(SYM, ("linker_file_lookup_symbol: nomem\n")); 650 return (0); 651 } 652 cp->address = (caddr_t)(cp + 1); 653 cp->name = cp->address + common_size; 654 strcpy(cp->name, name); 655 bzero(cp->address, common_size); 656 STAILQ_INSERT_TAIL(&file->common, cp, link); 657 658 KLD_DPF(SYM, ("linker_file_lookup_symbol: new common" 659 " value=%x\n", cp->address)); 660 return (cp->address); 661 } 662 KLD_DPF(SYM, ("linker_file_lookup_symbol: fail\n")); 663 return (0); 664 } 665 666 #ifdef DDB 667 /* 668 * DDB Helpers. DDB has to look across multiple files with their own symbol 669 * tables and string tables. 670 * 671 * Note that we do not obey list locking protocols here. We really don't need 672 * DDB to hang because somebody's got the lock held. We'll take the chance 673 * that the files list is inconsistant instead. 674 */ 675 676 int 677 linker_ddb_lookup(const char *symstr, c_linker_sym_t *sym) 678 { 679 linker_file_t lf; 680 681 TAILQ_FOREACH(lf, &linker_files, link) { 682 if (LINKER_LOOKUP_SYMBOL(lf, symstr, sym) == 0) 683 return (0); 684 } 685 return (ENOENT); 686 } 687 688 int 689 linker_ddb_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) 690 { 691 linker_file_t lf; 692 c_linker_sym_t best, es; 693 u_long diff, bestdiff, off; 694 695 best = 0; 696 off = (uintptr_t)value; 697 bestdiff = off; 698 TAILQ_FOREACH(lf, &linker_files, link) { 699 if (LINKER_SEARCH_SYMBOL(lf, value, &es, &diff) != 0) 700 continue; 701 if (es != 0 && diff < bestdiff) { 702 best = es; 703 bestdiff = diff; 704 } 705 if (bestdiff == 0) 706 break; 707 } 708 if (best) { 709 *sym = best; 710 *diffp = bestdiff; 711 return (0); 712 } else { 713 *sym = 0; 714 *diffp = off; 715 return (ENOENT); 716 } 717 } 718 719 int 720 linker_ddb_symbol_values(c_linker_sym_t sym, linker_symval_t *symval) 721 { 722 linker_file_t lf; 723 724 TAILQ_FOREACH(lf, &linker_files, link) { 725 if (LINKER_SYMBOL_VALUES(lf, sym, symval) == 0) 726 return (0); 727 } 728 return (ENOENT); 729 } 730 #endif 731 732 /* 733 * Syscalls. 734 */ 735 /* 736 * MPSAFE 737 */ 738 int 739 kldload(struct thread *td, struct kldload_args *uap) 740 { 741 char *kldname, *modname; 742 char *pathname = NULL; 743 linker_file_t lf; 744 int error = 0; 745 746 td->td_retval[0] = -1; 747 748 mtx_lock(&Giant); 749 750 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 751 goto out; 752 753 if ((error = suser(td)) != 0) 754 goto out; 755 756 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 757 if ((error = copyinstr(uap->file, pathname, MAXPATHLEN, 758 NULL)) != 0) 759 goto out; 760 761 /* 762 * If path do not contain qualified name or any dot in it 763 * (kldname.ko, or kldname.ver.ko) treat it as interface 764 * name. 765 */ 766 if (index(pathname, '/') || index(pathname, '.')) { 767 kldname = pathname; 768 modname = NULL; 769 } else { 770 kldname = NULL; 771 modname = pathname; 772 } 773 error = linker_load_module(kldname, modname, NULL, NULL, &lf); 774 if (error) 775 goto out; 776 777 lf->userrefs++; 778 td->td_retval[0] = lf->id; 779 out: 780 if (pathname) 781 free(pathname, M_TEMP); 782 mtx_unlock(&Giant); 783 return (error); 784 } 785 786 /* 787 * MPSAFE 788 */ 789 int 790 kldunload(struct thread *td, struct kldunload_args *uap) 791 { 792 linker_file_t lf; 793 int error = 0; 794 795 mtx_lock(&Giant); 796 797 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 798 goto out; 799 800 if ((error = suser(td)) != 0) 801 goto out; 802 803 lf = linker_find_file_by_id(uap->fileid); 804 if (lf) { 805 KLD_DPF(FILE, ("kldunload: lf->userrefs=%d\n", lf->userrefs)); 806 if (lf->userrefs == 0) { 807 printf("kldunload: attempt to unload file that was" 808 " loaded by the kernel\n"); 809 error = EBUSY; 810 goto out; 811 } 812 lf->userrefs--; 813 error = linker_file_unload(lf); 814 if (error) 815 lf->userrefs++; 816 } else 817 error = ENOENT; 818 out: 819 mtx_unlock(&Giant); 820 return (error); 821 } 822 823 /* 824 * MPSAFE 825 */ 826 int 827 kldfind(struct thread *td, struct kldfind_args *uap) 828 { 829 char *pathname; 830 const char *filename; 831 linker_file_t lf; 832 int error = 0; 833 834 #ifdef MAC 835 error = mac_check_kld_stat(td->td_ucred); 836 if (error) 837 return (error); 838 #endif 839 840 mtx_lock(&Giant); 841 td->td_retval[0] = -1; 842 843 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 844 if ((error = copyinstr(uap->file, pathname, MAXPATHLEN, 845 NULL)) != 0) 846 goto out; 847 848 filename = linker_basename(pathname); 849 lf = linker_find_file_by_name(filename); 850 if (lf) 851 td->td_retval[0] = lf->id; 852 else 853 error = ENOENT; 854 out: 855 if (pathname) 856 free(pathname, M_TEMP); 857 mtx_unlock(&Giant); 858 return (error); 859 } 860 861 /* 862 * MPSAFE 863 */ 864 int 865 kldnext(struct thread *td, struct kldnext_args *uap) 866 { 867 linker_file_t lf; 868 int error = 0; 869 870 #ifdef MAC 871 error = mac_check_kld_stat(td->td_ucred); 872 if (error) 873 return (error); 874 #endif 875 876 mtx_lock(&Giant); 877 878 if (uap->fileid == 0) { 879 mtx_lock(&kld_mtx); 880 if (TAILQ_FIRST(&linker_files)) 881 td->td_retval[0] = TAILQ_FIRST(&linker_files)->id; 882 else 883 td->td_retval[0] = 0; 884 mtx_unlock(&kld_mtx); 885 goto out; 886 } 887 lf = linker_find_file_by_id(uap->fileid); 888 if (lf) { 889 if (TAILQ_NEXT(lf, link)) 890 td->td_retval[0] = TAILQ_NEXT(lf, link)->id; 891 else 892 td->td_retval[0] = 0; 893 } else 894 error = ENOENT; 895 out: 896 mtx_unlock(&Giant); 897 return (error); 898 } 899 900 /* 901 * MPSAFE 902 */ 903 int 904 kldstat(struct thread *td, struct kldstat_args *uap) 905 { 906 linker_file_t lf; 907 int error = 0; 908 int namelen, version; 909 struct kld_file_stat *stat; 910 911 #ifdef MAC 912 error = mac_check_kld_stat(td->td_ucred); 913 if (error) 914 return (error); 915 #endif 916 917 mtx_lock(&Giant); 918 919 lf = linker_find_file_by_id(uap->fileid); 920 if (lf == NULL) { 921 error = ENOENT; 922 goto out; 923 } 924 stat = uap->stat; 925 926 /* 927 * Check the version of the user's structure. 928 */ 929 if ((error = copyin(&stat->version, &version, sizeof(version))) != 0) 930 goto out; 931 if (version != sizeof(struct kld_file_stat)) { 932 error = EINVAL; 933 goto out; 934 } 935 namelen = strlen(lf->filename) + 1; 936 if (namelen > MAXPATHLEN) 937 namelen = MAXPATHLEN; 938 if ((error = copyout(lf->filename, &stat->name[0], namelen)) != 0) 939 goto out; 940 if ((error = copyout(&lf->refs, &stat->refs, sizeof(int))) != 0) 941 goto out; 942 if ((error = copyout(&lf->id, &stat->id, sizeof(int))) != 0) 943 goto out; 944 if ((error = copyout(&lf->address, &stat->address, 945 sizeof(caddr_t))) != 0) 946 goto out; 947 if ((error = copyout(&lf->size, &stat->size, sizeof(size_t))) != 0) 948 goto out; 949 950 td->td_retval[0] = 0; 951 out: 952 mtx_unlock(&Giant); 953 return (error); 954 } 955 956 /* 957 * MPSAFE 958 */ 959 int 960 kldfirstmod(struct thread *td, struct kldfirstmod_args *uap) 961 { 962 linker_file_t lf; 963 module_t mp; 964 int error = 0; 965 966 #ifdef MAC 967 error = mac_check_kld_stat(td->td_ucred); 968 if (error) 969 return (error); 970 #endif 971 972 mtx_lock(&Giant); 973 lf = linker_find_file_by_id(uap->fileid); 974 if (lf) { 975 MOD_SLOCK; 976 mp = TAILQ_FIRST(&lf->modules); 977 if (mp != NULL) 978 td->td_retval[0] = module_getid(mp); 979 else 980 td->td_retval[0] = 0; 981 MOD_SUNLOCK; 982 } else 983 error = ENOENT; 984 mtx_unlock(&Giant); 985 return (error); 986 } 987 988 /* 989 * MPSAFE 990 */ 991 int 992 kldsym(struct thread *td, struct kldsym_args *uap) 993 { 994 char *symstr = NULL; 995 c_linker_sym_t sym; 996 linker_symval_t symval; 997 linker_file_t lf; 998 struct kld_sym_lookup lookup; 999 int error = 0; 1000 1001 #ifdef MAC 1002 error = mac_check_kld_stat(td->td_ucred); 1003 if (error) 1004 return (error); 1005 #endif 1006 1007 mtx_lock(&Giant); 1008 1009 if ((error = copyin(uap->data, &lookup, sizeof(lookup))) != 0) 1010 goto out; 1011 if (lookup.version != sizeof(lookup) || 1012 uap->cmd != KLDSYM_LOOKUP) { 1013 error = EINVAL; 1014 goto out; 1015 } 1016 symstr = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1017 if ((error = copyinstr(lookup.symname, symstr, MAXPATHLEN, NULL)) != 0) 1018 goto out; 1019 if (uap->fileid != 0) { 1020 lf = linker_find_file_by_id(uap->fileid); 1021 if (lf == NULL) { 1022 error = ENOENT; 1023 goto out; 1024 } 1025 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 1026 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 1027 lookup.symvalue = (uintptr_t) symval.value; 1028 lookup.symsize = symval.size; 1029 error = copyout(&lookup, uap->data, 1030 sizeof(lookup)); 1031 } else 1032 error = ENOENT; 1033 } else { 1034 mtx_lock(&kld_mtx); 1035 TAILQ_FOREACH(lf, &linker_files, link) { 1036 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 1037 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 1038 lookup.symvalue = (uintptr_t)symval.value; 1039 lookup.symsize = symval.size; 1040 error = copyout(&lookup, uap->data, 1041 sizeof(lookup)); 1042 break; 1043 } 1044 } 1045 mtx_unlock(&kld_mtx); 1046 if (lf == NULL) 1047 error = ENOENT; 1048 } 1049 out: 1050 if (symstr) 1051 free(symstr, M_TEMP); 1052 mtx_unlock(&Giant); 1053 return (error); 1054 } 1055 1056 /* 1057 * Preloaded module support 1058 */ 1059 1060 static modlist_t 1061 modlist_lookup(const char *name, int ver) 1062 { 1063 modlist_t mod; 1064 1065 TAILQ_FOREACH(mod, &found_modules, link) { 1066 if (strcmp(mod->name, name) == 0 && 1067 (ver == 0 || mod->version == ver)) 1068 return (mod); 1069 } 1070 return (NULL); 1071 } 1072 1073 static modlist_t 1074 modlist_lookup2(const char *name, struct mod_depend *verinfo) 1075 { 1076 modlist_t mod, bestmod; 1077 int ver; 1078 1079 if (verinfo == NULL) 1080 return (modlist_lookup(name, 0)); 1081 bestmod = NULL; 1082 for (mod = TAILQ_FIRST(&found_modules); mod; 1083 mod = TAILQ_NEXT(mod, link)) { 1084 if (strcmp(mod->name, name) != 0) 1085 continue; 1086 ver = mod->version; 1087 if (ver == verinfo->md_ver_preferred) 1088 return (mod); 1089 if (ver >= verinfo->md_ver_minimum && 1090 ver <= verinfo->md_ver_maximum && 1091 ver > bestmod->version) 1092 bestmod = mod; 1093 } 1094 return (bestmod); 1095 } 1096 1097 static modlist_t 1098 modlist_newmodule(const char *modname, int version, linker_file_t container) 1099 { 1100 modlist_t mod; 1101 1102 mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT | M_ZERO); 1103 if (mod == NULL) 1104 panic("no memory for module list"); 1105 mod->container = container; 1106 mod->name = modname; 1107 mod->version = version; 1108 TAILQ_INSERT_TAIL(&found_modules, mod, link); 1109 return (mod); 1110 } 1111 1112 /* 1113 * This routine is cheap and nasty but will work for data pointers. 1114 */ 1115 static void * 1116 linker_reloc_ptr(linker_file_t lf, const void *offset) 1117 { 1118 return (lf->address + (uintptr_t)offset); 1119 } 1120 1121 /* 1122 * Dereference MDT_VERSION metadata into module name and version 1123 */ 1124 static void 1125 linker_mdt_version(linker_file_t lf, struct mod_metadata *mp, 1126 const char **modname, int *version) 1127 { 1128 struct mod_version *mvp; 1129 1130 if (modname) 1131 *modname = linker_reloc_ptr(lf, mp->md_cval); 1132 if (version) { 1133 mvp = linker_reloc_ptr(lf, mp->md_data); 1134 *version = mvp->mv_version; 1135 } 1136 } 1137 1138 /* 1139 * Dereference MDT_DEPEND metadata into module name and mod_depend structure 1140 */ 1141 static void 1142 linker_mdt_depend(linker_file_t lf, struct mod_metadata *mp, 1143 const char **modname, struct mod_depend **verinfo) 1144 { 1145 1146 if (modname) 1147 *modname = linker_reloc_ptr(lf, mp->md_cval); 1148 if (verinfo) 1149 *verinfo = linker_reloc_ptr(lf, mp->md_data); 1150 } 1151 1152 static void 1153 linker_addmodules(linker_file_t lf, struct mod_metadata **start, 1154 struct mod_metadata **stop, int preload) 1155 { 1156 struct mod_metadata *mp, **mdp; 1157 const char *modname; 1158 int ver; 1159 1160 for (mdp = start; mdp < stop; mdp++) { 1161 if (preload) 1162 mp = *mdp; 1163 else 1164 mp = linker_reloc_ptr(lf, *mdp); 1165 if (mp->md_type != MDT_VERSION) 1166 continue; 1167 if (preload) { 1168 modname = mp->md_cval; 1169 ver = ((struct mod_version *)mp->md_data)->mv_version; 1170 } else 1171 linker_mdt_version(lf, mp, &modname, &ver); 1172 if (modlist_lookup(modname, ver) != NULL) { 1173 printf("module %s already present!\n", modname); 1174 /* XXX what can we do? this is a build error. :-( */ 1175 continue; 1176 } 1177 modlist_newmodule(modname, ver, lf); 1178 } 1179 } 1180 1181 static void 1182 linker_preload(void *arg) 1183 { 1184 caddr_t modptr; 1185 const char *modname, *nmodname; 1186 char *modtype; 1187 linker_file_t lf; 1188 linker_class_t lc; 1189 int error; 1190 linker_file_list_t loaded_files; 1191 linker_file_list_t depended_files; 1192 struct mod_metadata *mp, *nmp; 1193 struct mod_metadata **start, **stop, **mdp, **nmdp; 1194 struct mod_depend *verinfo; 1195 int nver; 1196 int resolves; 1197 modlist_t mod; 1198 struct sysinit **si_start, **si_stop; 1199 1200 TAILQ_INIT(&loaded_files); 1201 TAILQ_INIT(&depended_files); 1202 TAILQ_INIT(&found_modules); 1203 error = 0; 1204 1205 modptr = NULL; 1206 while ((modptr = preload_search_next_name(modptr)) != NULL) { 1207 modname = (char *)preload_search_info(modptr, MODINFO_NAME); 1208 modtype = (char *)preload_search_info(modptr, MODINFO_TYPE); 1209 if (modname == NULL) { 1210 printf("Preloaded module at %p does not have a" 1211 " name!\n", modptr); 1212 continue; 1213 } 1214 if (modtype == NULL) { 1215 printf("Preloaded module at %p does not have a type!\n", 1216 modptr); 1217 continue; 1218 } 1219 printf("Preloaded %s \"%s\" at %p.\n", modtype, modname, 1220 modptr); 1221 lf = NULL; 1222 TAILQ_FOREACH(lc, &classes, link) { 1223 error = LINKER_LINK_PRELOAD(lc, modname, &lf); 1224 if (error) { 1225 lf = NULL; 1226 break; 1227 } 1228 } 1229 if (lf) 1230 TAILQ_INSERT_TAIL(&loaded_files, lf, loaded); 1231 } 1232 1233 /* 1234 * First get a list of stuff in the kernel. 1235 */ 1236 if (linker_file_lookup_set(linker_kernel_file, MDT_SETNAME, &start, 1237 &stop, NULL) == 0) 1238 linker_addmodules(linker_kernel_file, start, stop, 1); 1239 1240 /* 1241 * this is a once-off kinky bubble sort resolve relocation dependency 1242 * requirements 1243 */ 1244 restart: 1245 TAILQ_FOREACH(lf, &loaded_files, loaded) { 1246 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1247 &stop, NULL); 1248 /* 1249 * First, look to see if we would successfully link with this 1250 * stuff. 1251 */ 1252 resolves = 1; /* unless we know otherwise */ 1253 if (!error) { 1254 for (mdp = start; mdp < stop; mdp++) { 1255 mp = linker_reloc_ptr(lf, *mdp); 1256 if (mp->md_type != MDT_DEPEND) 1257 continue; 1258 linker_mdt_depend(lf, mp, &modname, &verinfo); 1259 for (nmdp = start; nmdp < stop; nmdp++) { 1260 nmp = linker_reloc_ptr(lf, *nmdp); 1261 if (nmp->md_type != MDT_VERSION) 1262 continue; 1263 linker_mdt_version(lf, nmp, &nmodname, 1264 NULL); 1265 nmodname = linker_reloc_ptr(lf, 1266 nmp->md_cval); 1267 if (strcmp(modname, nmodname) == 0) 1268 break; 1269 } 1270 if (nmdp < stop) /* it's a self reference */ 1271 continue; 1272 1273 /* 1274 * ok, the module isn't here yet, we 1275 * are not finished 1276 */ 1277 if (modlist_lookup2(modname, verinfo) == NULL) 1278 resolves = 0; 1279 } 1280 } 1281 /* 1282 * OK, if we found our modules, we can link. So, "provide" 1283 * the modules inside and add it to the end of the link order 1284 * list. 1285 */ 1286 if (resolves) { 1287 if (!error) { 1288 for (mdp = start; mdp < stop; mdp++) { 1289 mp = linker_reloc_ptr(lf, *mdp); 1290 if (mp->md_type != MDT_VERSION) 1291 continue; 1292 linker_mdt_version(lf, mp, 1293 &modname, &nver); 1294 if (modlist_lookup(modname, 1295 nver) != NULL) { 1296 printf("module %s already" 1297 " present!\n", modname); 1298 linker_file_unload(lf); 1299 TAILQ_REMOVE(&loaded_files, 1300 lf, loaded); 1301 /* we changed tailq next ptr */ 1302 goto restart; 1303 } 1304 modlist_newmodule(modname, nver, lf); 1305 } 1306 } 1307 TAILQ_REMOVE(&loaded_files, lf, loaded); 1308 TAILQ_INSERT_TAIL(&depended_files, lf, loaded); 1309 /* 1310 * Since we provided modules, we need to restart the 1311 * sort so that the previous files that depend on us 1312 * have a chance. Also, we've busted the tailq next 1313 * pointer with the REMOVE. 1314 */ 1315 goto restart; 1316 } 1317 } 1318 1319 /* 1320 * At this point, we check to see what could not be resolved.. 1321 */ 1322 TAILQ_FOREACH(lf, &loaded_files, loaded) { 1323 printf("KLD file %s is missing dependencies\n", lf->filename); 1324 linker_file_unload(lf); 1325 TAILQ_REMOVE(&loaded_files, lf, loaded); 1326 } 1327 1328 /* 1329 * We made it. Finish off the linking in the order we determined. 1330 */ 1331 TAILQ_FOREACH(lf, &depended_files, loaded) { 1332 if (linker_kernel_file) { 1333 linker_kernel_file->refs++; 1334 error = linker_file_add_dependency(lf, 1335 linker_kernel_file); 1336 if (error) 1337 panic("cannot add dependency"); 1338 } 1339 lf->userrefs++; /* so we can (try to) kldunload it */ 1340 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1341 &stop, NULL); 1342 if (!error) { 1343 for (mdp = start; mdp < stop; mdp++) { 1344 mp = linker_reloc_ptr(lf, *mdp); 1345 if (mp->md_type != MDT_DEPEND) 1346 continue; 1347 linker_mdt_depend(lf, mp, &modname, &verinfo); 1348 mod = modlist_lookup2(modname, verinfo); 1349 mod->container->refs++; 1350 error = linker_file_add_dependency(lf, 1351 mod->container); 1352 if (error) 1353 panic("cannot add dependency"); 1354 } 1355 } 1356 /* 1357 * Now do relocation etc using the symbol search paths 1358 * established by the dependencies 1359 */ 1360 error = LINKER_LINK_PRELOAD_FINISH(lf); 1361 if (error) { 1362 printf("KLD file %s - could not finalize loading\n", 1363 lf->filename); 1364 linker_file_unload(lf); 1365 continue; 1366 } 1367 linker_file_register_modules(lf); 1368 if (linker_file_lookup_set(lf, "sysinit_set", &si_start, 1369 &si_stop, NULL) == 0) 1370 sysinit_add(si_start, si_stop); 1371 linker_file_register_sysctls(lf); 1372 lf->flags |= LINKER_FILE_LINKED; 1373 } 1374 /* woohoo! we made it! */ 1375 } 1376 1377 SYSINIT(preload, SI_SUB_KLD, SI_ORDER_MIDDLE, linker_preload, 0) 1378 1379 /* 1380 * Search for a not-loaded module by name. 1381 * 1382 * Modules may be found in the following locations: 1383 * 1384 * - preloaded (result is just the module name) - on disk (result is full path 1385 * to module) 1386 * 1387 * If the module name is qualified in any way (contains path, etc.) the we 1388 * simply return a copy of it. 1389 * 1390 * The search path can be manipulated via sysctl. Note that we use the ';' 1391 * character as a separator to be consistent with the bootloader. 1392 */ 1393 1394 static char linker_hintfile[] = "linker.hints"; 1395 static char linker_path[MAXPATHLEN] = "/boot/kernel;/boot/modules;/modules"; 1396 1397 SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RW, linker_path, 1398 sizeof(linker_path), "module load search path"); 1399 1400 TUNABLE_STR("module_path", linker_path, sizeof(linker_path)); 1401 1402 static char *linker_ext_list[] = { 1403 "", 1404 ".ko", 1405 NULL 1406 }; 1407 1408 /* 1409 * Check if file actually exists either with or without extension listed in 1410 * the linker_ext_list. (probably should be generic for the rest of the 1411 * kernel) 1412 */ 1413 static char * 1414 linker_lookup_file(const char *path, int pathlen, const char *name, 1415 int namelen, struct vattr *vap) 1416 { 1417 struct nameidata nd; 1418 struct thread *td = curthread; /* XXX */ 1419 char *result, **cpp, *sep; 1420 int error, len, extlen, reclen, flags; 1421 enum vtype type; 1422 1423 extlen = 0; 1424 for (cpp = linker_ext_list; *cpp; cpp++) { 1425 len = strlen(*cpp); 1426 if (len > extlen) 1427 extlen = len; 1428 } 1429 extlen++; /* trailing '\0' */ 1430 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1431 1432 reclen = pathlen + strlen(sep) + namelen + extlen + 1; 1433 result = malloc(reclen, M_LINKER, M_WAITOK); 1434 for (cpp = linker_ext_list; *cpp; cpp++) { 1435 snprintf(result, reclen, "%.*s%s%.*s%s", pathlen, path, sep, 1436 namelen, name, *cpp); 1437 /* 1438 * Attempt to open the file, and return the path if 1439 * we succeed and it's a regular file. 1440 */ 1441 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, result, td); 1442 flags = FREAD; 1443 error = vn_open(&nd, &flags, 0); 1444 if (error == 0) { 1445 NDFREE(&nd, NDF_ONLY_PNBUF); 1446 type = nd.ni_vp->v_type; 1447 if (vap) 1448 VOP_GETATTR(nd.ni_vp, vap, td->td_ucred, td); 1449 VOP_UNLOCK(nd.ni_vp, 0, td); 1450 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 1451 if (type == VREG) 1452 return (result); 1453 } 1454 } 1455 free(result, M_LINKER); 1456 return (NULL); 1457 } 1458 1459 #define INT_ALIGN(base, ptr) ptr = \ 1460 (base) + (((ptr) - (base) + sizeof(int) - 1) & ~(sizeof(int) - 1)) 1461 1462 /* 1463 * Lookup KLD which contains requested module in the "linker.hints" file. If 1464 * version specification is available, then try to find the best KLD. 1465 * Otherwise just find the latest one. 1466 */ 1467 static char * 1468 linker_hints_lookup(const char *path, int pathlen, const char *modname, 1469 int modnamelen, struct mod_depend *verinfo) 1470 { 1471 struct thread *td = curthread; /* XXX */ 1472 struct ucred *cred = td ? td->td_ucred : NULL; 1473 struct nameidata nd; 1474 struct vattr vattr, mattr; 1475 u_char *hints = NULL; 1476 u_char *cp, *recptr, *bufend, *result, *best, *pathbuf, *sep; 1477 int error, ival, bestver, *intp, reclen, found, flags, clen, blen; 1478 1479 result = NULL; 1480 bestver = found = 0; 1481 1482 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1483 reclen = imax(modnamelen, strlen(linker_hintfile)) + pathlen + 1484 strlen(sep) + 1; 1485 pathbuf = malloc(reclen, M_LINKER, M_WAITOK); 1486 snprintf(pathbuf, reclen, "%.*s%s%s", pathlen, path, sep, 1487 linker_hintfile); 1488 1489 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, pathbuf, td); 1490 flags = FREAD; 1491 error = vn_open(&nd, &flags, 0); 1492 if (error) 1493 goto bad; 1494 NDFREE(&nd, NDF_ONLY_PNBUF); 1495 if (nd.ni_vp->v_type != VREG) 1496 goto bad; 1497 best = cp = NULL; 1498 error = VOP_GETATTR(nd.ni_vp, &vattr, cred, td); 1499 if (error) 1500 goto bad; 1501 /* 1502 * XXX: we need to limit this number to some reasonable value 1503 */ 1504 if (vattr.va_size > 100 * 1024) { 1505 printf("hints file too large %ld\n", (long)vattr.va_size); 1506 goto bad; 1507 } 1508 hints = malloc(vattr.va_size, M_TEMP, M_WAITOK); 1509 if (hints == NULL) 1510 goto bad; 1511 error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)hints, vattr.va_size, 0, 1512 UIO_SYSSPACE, IO_NODELOCKED, cred, NOCRED, &reclen, td); 1513 if (error) 1514 goto bad; 1515 VOP_UNLOCK(nd.ni_vp, 0, td); 1516 vn_close(nd.ni_vp, FREAD, cred, td); 1517 nd.ni_vp = NULL; 1518 if (reclen != 0) { 1519 printf("can't read %d\n", reclen); 1520 goto bad; 1521 } 1522 intp = (int *)hints; 1523 ival = *intp++; 1524 if (ival != LINKER_HINTS_VERSION) { 1525 printf("hints file version mismatch %d\n", ival); 1526 goto bad; 1527 } 1528 bufend = hints + vattr.va_size; 1529 recptr = (u_char *)intp; 1530 clen = blen = 0; 1531 while (recptr < bufend && !found) { 1532 intp = (int *)recptr; 1533 reclen = *intp++; 1534 ival = *intp++; 1535 cp = (char *)intp; 1536 switch (ival) { 1537 case MDT_VERSION: 1538 clen = *cp++; 1539 if (clen != modnamelen || bcmp(cp, modname, clen) != 0) 1540 break; 1541 cp += clen; 1542 INT_ALIGN(hints, cp); 1543 ival = *(int *)cp; 1544 cp += sizeof(int); 1545 clen = *cp++; 1546 if (verinfo == NULL || 1547 ival == verinfo->md_ver_preferred) { 1548 found = 1; 1549 break; 1550 } 1551 if (ival >= verinfo->md_ver_minimum && 1552 ival <= verinfo->md_ver_maximum && 1553 ival > bestver) { 1554 bestver = ival; 1555 best = cp; 1556 blen = clen; 1557 } 1558 break; 1559 default: 1560 break; 1561 } 1562 recptr += reclen + sizeof(int); 1563 } 1564 /* 1565 * Finally check if KLD is in the place 1566 */ 1567 if (found) 1568 result = linker_lookup_file(path, pathlen, cp, clen, &mattr); 1569 else if (best) 1570 result = linker_lookup_file(path, pathlen, best, blen, &mattr); 1571 1572 /* 1573 * KLD is newer than hints file. What we should do now? 1574 */ 1575 if (result && timespeccmp(&mattr.va_mtime, &vattr.va_mtime, >)) 1576 printf("warning: KLD '%s' is newer than the linker.hints" 1577 " file\n", result); 1578 bad: 1579 free(pathbuf, M_LINKER); 1580 if (hints) 1581 free(hints, M_TEMP); 1582 if (nd.ni_vp != NULL) { 1583 VOP_UNLOCK(nd.ni_vp, 0, td); 1584 vn_close(nd.ni_vp, FREAD, cred, td); 1585 } 1586 /* 1587 * If nothing found or hints is absent - fallback to the old 1588 * way by using "kldname[.ko]" as module name. 1589 */ 1590 if (!found && !bestver && result == NULL) 1591 result = linker_lookup_file(path, pathlen, modname, 1592 modnamelen, NULL); 1593 return (result); 1594 } 1595 1596 /* 1597 * Lookup KLD which contains requested module in the all directories. 1598 */ 1599 static char * 1600 linker_search_module(const char *modname, int modnamelen, 1601 struct mod_depend *verinfo) 1602 { 1603 char *cp, *ep, *result; 1604 1605 /* 1606 * traverse the linker path 1607 */ 1608 for (cp = linker_path; *cp; cp = ep + 1) { 1609 /* find the end of this component */ 1610 for (ep = cp; (*ep != 0) && (*ep != ';'); ep++); 1611 result = linker_hints_lookup(cp, ep - cp, modname, 1612 modnamelen, verinfo); 1613 if (result != NULL) 1614 return (result); 1615 if (*ep == 0) 1616 break; 1617 } 1618 return (NULL); 1619 } 1620 1621 /* 1622 * Search for module in all directories listed in the linker_path. 1623 */ 1624 static char * 1625 linker_search_kld(const char *name) 1626 { 1627 char *cp, *ep, *result, **cpp; 1628 int extlen, len; 1629 1630 /* qualified at all? */ 1631 if (index(name, '/')) 1632 return (linker_strdup(name)); 1633 1634 extlen = 0; 1635 for (cpp = linker_ext_list; *cpp; cpp++) { 1636 len = strlen(*cpp); 1637 if (len > extlen) 1638 extlen = len; 1639 } 1640 extlen++; /* trailing '\0' */ 1641 1642 /* traverse the linker path */ 1643 len = strlen(name); 1644 for (ep = linker_path; *ep; ep++) { 1645 cp = ep; 1646 /* find the end of this component */ 1647 for (; *ep != 0 && *ep != ';'; ep++); 1648 result = linker_lookup_file(cp, ep - cp, name, len, NULL); 1649 if (result != NULL) 1650 return (result); 1651 } 1652 return (NULL); 1653 } 1654 1655 static const char * 1656 linker_basename(const char *path) 1657 { 1658 const char *filename; 1659 1660 filename = rindex(path, '/'); 1661 if (filename == NULL) 1662 return path; 1663 if (filename[1]) 1664 filename++; 1665 return (filename); 1666 } 1667 1668 /* 1669 * Find a file which contains given module and load it, if "parent" is not 1670 * NULL, register a reference to it. 1671 */ 1672 int 1673 linker_load_module(const char *kldname, const char *modname, 1674 struct linker_file *parent, struct mod_depend *verinfo, 1675 struct linker_file **lfpp) 1676 { 1677 linker_file_t lfdep; 1678 const char *filename; 1679 char *pathname; 1680 int error; 1681 1682 if (modname == NULL) { 1683 /* 1684 * We have to load KLD 1685 */ 1686 KASSERT(verinfo == NULL, ("linker_load_module: verinfo" 1687 " is not NULL")); 1688 pathname = linker_search_kld(kldname); 1689 } else { 1690 if (modlist_lookup2(modname, verinfo) != NULL) 1691 return (EEXIST); 1692 if (kldname != NULL) 1693 pathname = linker_strdup(kldname); 1694 else if (rootvnode == NULL) 1695 pathname = NULL; 1696 else 1697 /* 1698 * Need to find a KLD with required module 1699 */ 1700 pathname = linker_search_module(modname, 1701 strlen(modname), verinfo); 1702 } 1703 if (pathname == NULL) 1704 return (ENOENT); 1705 1706 /* 1707 * Can't load more than one file with the same basename XXX: 1708 * Actually it should be possible to have multiple KLDs with 1709 * the same basename but different path because they can 1710 * provide different versions of the same modules. 1711 */ 1712 filename = linker_basename(pathname); 1713 if (linker_find_file_by_name(filename)) { 1714 error = EEXIST; 1715 goto out; 1716 } 1717 do { 1718 error = linker_load_file(pathname, &lfdep); 1719 if (error) 1720 break; 1721 if (modname && verinfo && 1722 modlist_lookup2(modname, verinfo) == NULL) { 1723 linker_file_unload(lfdep); 1724 error = ENOENT; 1725 break; 1726 } 1727 if (parent) { 1728 error = linker_file_add_dependency(parent, lfdep); 1729 if (error) 1730 break; 1731 } 1732 if (lfpp) 1733 *lfpp = lfdep; 1734 } while (0); 1735 out: 1736 if (pathname) 1737 free(pathname, M_LINKER); 1738 return (error); 1739 } 1740 1741 /* 1742 * This routine is responsible for finding dependencies of userland initiated 1743 * kldload(2)'s of files. 1744 */ 1745 int 1746 linker_load_dependencies(linker_file_t lf) 1747 { 1748 linker_file_t lfdep; 1749 struct mod_metadata **start, **stop, **mdp, **nmdp; 1750 struct mod_metadata *mp, *nmp; 1751 struct mod_depend *verinfo; 1752 modlist_t mod; 1753 const char *modname, *nmodname; 1754 int ver, error = 0, count; 1755 1756 /* 1757 * All files are dependant on /kernel. 1758 */ 1759 if (linker_kernel_file) { 1760 linker_kernel_file->refs++; 1761 error = linker_file_add_dependency(lf, linker_kernel_file); 1762 if (error) 1763 return (error); 1764 } 1765 if (linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop, 1766 &count) != 0) 1767 return (0); 1768 for (mdp = start; mdp < stop; mdp++) { 1769 mp = linker_reloc_ptr(lf, *mdp); 1770 if (mp->md_type != MDT_VERSION) 1771 continue; 1772 linker_mdt_version(lf, mp, &modname, &ver); 1773 mod = modlist_lookup(modname, ver); 1774 if (mod != NULL) { 1775 printf("interface %s.%d already present in the KLD" 1776 " '%s'!\n", modname, ver, 1777 mod->container->filename); 1778 return (EEXIST); 1779 } 1780 } 1781 1782 for (mdp = start; mdp < stop; mdp++) { 1783 mp = linker_reloc_ptr(lf, *mdp); 1784 if (mp->md_type != MDT_DEPEND) 1785 continue; 1786 linker_mdt_depend(lf, mp, &modname, &verinfo); 1787 nmodname = NULL; 1788 for (nmdp = start; nmdp < stop; nmdp++) { 1789 nmp = linker_reloc_ptr(lf, *nmdp); 1790 if (nmp->md_type != MDT_VERSION) 1791 continue; 1792 nmodname = linker_reloc_ptr(lf, nmp->md_cval); 1793 if (strcmp(modname, nmodname) == 0) 1794 break; 1795 } 1796 if (nmdp < stop)/* early exit, it's a self reference */ 1797 continue; 1798 mod = modlist_lookup2(modname, verinfo); 1799 if (mod) { /* woohoo, it's loaded already */ 1800 lfdep = mod->container; 1801 lfdep->refs++; 1802 error = linker_file_add_dependency(lf, lfdep); 1803 if (error) 1804 break; 1805 continue; 1806 } 1807 error = linker_load_module(NULL, modname, lf, verinfo, NULL); 1808 if (error) { 1809 printf("KLD %s: depends on %s - not available\n", 1810 lf->filename, modname); 1811 break; 1812 } 1813 } 1814 1815 if (error) 1816 return (error); 1817 linker_addmodules(lf, start, stop, 0); 1818 return (error); 1819 } 1820 1821 static int 1822 sysctl_kern_function_list_iterate(const char *name, void *opaque) 1823 { 1824 struct sysctl_req *req; 1825 1826 req = opaque; 1827 return (SYSCTL_OUT(req, name, strlen(name) + 1)); 1828 } 1829 1830 /* 1831 * Export a nul-separated, double-nul-terminated list of all function names 1832 * in the kernel. 1833 */ 1834 static int 1835 sysctl_kern_function_list(SYSCTL_HANDLER_ARGS) 1836 { 1837 linker_file_t lf; 1838 int error; 1839 1840 #ifdef MAC 1841 error = mac_check_kld_stat(req->td->td_ucred); 1842 if (error) 1843 return (error); 1844 #endif 1845 sysctl_wire_old_buffer(req, 0); 1846 mtx_lock(&kld_mtx); 1847 TAILQ_FOREACH(lf, &linker_files, link) { 1848 error = LINKER_EACH_FUNCTION_NAME(lf, 1849 sysctl_kern_function_list_iterate, req); 1850 if (error) { 1851 mtx_unlock(&kld_mtx); 1852 return (error); 1853 } 1854 } 1855 mtx_unlock(&kld_mtx); 1856 return (SYSCTL_OUT(req, "", 1)); 1857 } 1858 1859 SYSCTL_PROC(_kern, OID_AUTO, function_list, CTLFLAG_RD, 1860 NULL, 0, sysctl_kern_function_list, "", "kernel function list");
Cache object: 555c038c182a83c41e57decd5b8ed9db
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