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 27 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD$"); 29 30 #include "opt_ddb.h" 31 #include "opt_hwpmc_hooks.h" 32 33 #include <sys/param.h> 34 #include <sys/kernel.h> 35 #include <sys/systm.h> 36 #include <sys/malloc.h> 37 #include <sys/sysproto.h> 38 #include <sys/sysent.h> 39 #include <sys/priv.h> 40 #include <sys/proc.h> 41 #include <sys/lock.h> 42 #include <sys/mutex.h> 43 #include <sys/sx.h> 44 #include <sys/module.h> 45 #include <sys/mount.h> 46 #include <sys/linker.h> 47 #include <sys/fcntl.h> 48 #include <sys/jail.h> 49 #include <sys/libkern.h> 50 #include <sys/namei.h> 51 #include <sys/vnode.h> 52 #include <sys/syscallsubr.h> 53 #include <sys/sysctl.h> 54 55 #include <net/vnet.h> 56 57 #include <security/mac/mac_framework.h> 58 59 #include "linker_if.h" 60 61 #ifdef HWPMC_HOOKS 62 #include <sys/pmckern.h> 63 #endif 64 65 #ifdef KLD_DEBUG 66 int kld_debug = 0; 67 SYSCTL_INT(_debug, OID_AUTO, kld_debug, CTLFLAG_RW, 68 &kld_debug, 0, "Set various levels of KLD debug"); 69 #endif 70 71 #define KLD_LOCK() sx_xlock(&kld_sx) 72 #define KLD_UNLOCK() sx_xunlock(&kld_sx) 73 #define KLD_LOCKED() sx_xlocked(&kld_sx) 74 #define KLD_LOCK_ASSERT() do { \ 75 if (!cold) \ 76 sx_assert(&kld_sx, SX_XLOCKED); \ 77 } while (0) 78 79 /* 80 * static char *linker_search_path(const char *name, struct mod_depend 81 * *verinfo); 82 */ 83 static const char *linker_basename(const char *path); 84 85 /* 86 * Find a currently loaded file given its filename. 87 */ 88 static linker_file_t linker_find_file_by_name(const char* _filename); 89 90 /* 91 * Find a currently loaded file given its file id. 92 */ 93 static linker_file_t linker_find_file_by_id(int _fileid); 94 95 /* Metadata from the static kernel */ 96 SET_DECLARE(modmetadata_set, struct mod_metadata); 97 98 MALLOC_DEFINE(M_LINKER, "linker", "kernel linker"); 99 100 linker_file_t linker_kernel_file; 101 102 static struct sx kld_sx; /* kernel linker lock */ 103 104 /* 105 * Load counter used by clients to determine if a linker file has been 106 * re-loaded. This counter is incremented for each file load. 107 */ 108 static int loadcnt; 109 110 static linker_class_list_t classes; 111 static linker_file_list_t linker_files; 112 static int next_file_id = 1; 113 static int linker_no_more_classes = 0; 114 115 #define LINKER_GET_NEXT_FILE_ID(a) do { \ 116 linker_file_t lftmp; \ 117 \ 118 KLD_LOCK_ASSERT(); \ 119 retry: \ 120 TAILQ_FOREACH(lftmp, &linker_files, link) { \ 121 if (next_file_id == lftmp->id) { \ 122 next_file_id++; \ 123 goto retry; \ 124 } \ 125 } \ 126 (a) = next_file_id; \ 127 } while(0) 128 129 130 /* XXX wrong name; we're looking at version provision tags here, not modules */ 131 typedef TAILQ_HEAD(, modlist) modlisthead_t; 132 struct modlist { 133 TAILQ_ENTRY(modlist) link; /* chain together all modules */ 134 linker_file_t container; 135 const char *name; 136 int version; 137 }; 138 typedef struct modlist *modlist_t; 139 static modlisthead_t found_modules; 140 141 static int linker_file_add_dependency(linker_file_t file, 142 linker_file_t dep); 143 static caddr_t linker_file_lookup_symbol_internal(linker_file_t file, 144 const char* name, int deps); 145 static int linker_load_module(const char *kldname, 146 const char *modname, struct linker_file *parent, 147 struct mod_depend *verinfo, struct linker_file **lfpp); 148 static modlist_t modlist_lookup2(const char *name, struct mod_depend *verinfo); 149 150 static char * 151 linker_strdup(const char *str) 152 { 153 char *result; 154 155 if ((result = malloc((strlen(str) + 1), M_LINKER, M_WAITOK)) != NULL) 156 strcpy(result, str); 157 return (result); 158 } 159 160 static void 161 linker_init(void *arg) 162 { 163 164 sx_init(&kld_sx, "kernel linker"); 165 TAILQ_INIT(&classes); 166 TAILQ_INIT(&linker_files); 167 } 168 169 SYSINIT(linker, SI_SUB_KLD, SI_ORDER_FIRST, linker_init, 0); 170 171 static void 172 linker_stop_class_add(void *arg) 173 { 174 175 linker_no_more_classes = 1; 176 } 177 178 SYSINIT(linker_class, SI_SUB_KLD, SI_ORDER_ANY, linker_stop_class_add, NULL); 179 180 int 181 linker_add_class(linker_class_t lc) 182 { 183 184 /* 185 * We disallow any class registration past SI_ORDER_ANY 186 * of SI_SUB_KLD. We bump the reference count to keep the 187 * ops from being freed. 188 */ 189 if (linker_no_more_classes == 1) 190 return (EPERM); 191 kobj_class_compile((kobj_class_t) lc); 192 ((kobj_class_t)lc)->refs++; /* XXX: kobj_mtx */ 193 TAILQ_INSERT_TAIL(&classes, lc, link); 194 return (0); 195 } 196 197 static void 198 linker_file_sysinit(linker_file_t lf) 199 { 200 struct sysinit **start, **stop, **sipp, **xipp, *save; 201 202 KLD_DPF(FILE, ("linker_file_sysinit: calling SYSINITs for %s\n", 203 lf->filename)); 204 205 if (linker_file_lookup_set(lf, "sysinit_set", &start, &stop, NULL) != 0) 206 return; 207 /* 208 * Perform a bubble sort of the system initialization objects by 209 * 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 mtx_lock(&Giant); 231 for (sipp = start; sipp < stop; sipp++) { 232 if ((*sipp)->subsystem == SI_SUB_DUMMY) 233 continue; /* skip dummy task(s) */ 234 235 /* Call function */ 236 (*((*sipp)->func)) ((*sipp)->udata); 237 } 238 mtx_unlock(&Giant); 239 } 240 241 static void 242 linker_file_sysuninit(linker_file_t lf) 243 { 244 struct sysinit **start, **stop, **sipp, **xipp, *save; 245 246 KLD_DPF(FILE, ("linker_file_sysuninit: calling SYSUNINITs for %s\n", 247 lf->filename)); 248 249 if (linker_file_lookup_set(lf, "sysuninit_set", &start, &stop, 250 NULL) != 0) 251 return; 252 253 /* 254 * Perform a reverse bubble sort of the system initialization objects 255 * by their subsystem (primary key) and order (secondary key). 256 * 257 * Since some things care about execution order, this is the operation 258 * which ensures continued function. 259 */ 260 for (sipp = start; sipp < stop; sipp++) { 261 for (xipp = sipp + 1; xipp < stop; xipp++) { 262 if ((*sipp)->subsystem > (*xipp)->subsystem || 263 ((*sipp)->subsystem == (*xipp)->subsystem && 264 (*sipp)->order >= (*xipp)->order)) 265 continue; /* skip */ 266 save = *sipp; 267 *sipp = *xipp; 268 *xipp = save; 269 } 270 } 271 272 /* 273 * Traverse the (now) ordered list of system initialization tasks. 274 * Perform each task, and continue on to the next task. 275 */ 276 mtx_lock(&Giant); 277 for (sipp = start; sipp < stop; sipp++) { 278 if ((*sipp)->subsystem == SI_SUB_DUMMY) 279 continue; /* skip dummy task(s) */ 280 281 /* Call function */ 282 (*((*sipp)->func)) ((*sipp)->udata); 283 } 284 mtx_unlock(&Giant); 285 } 286 287 static void 288 linker_file_register_sysctls(linker_file_t lf) 289 { 290 struct sysctl_oid **start, **stop, **oidp; 291 292 KLD_DPF(FILE, 293 ("linker_file_register_sysctls: registering SYSCTLs for %s\n", 294 lf->filename)); 295 296 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0) 297 return; 298 299 sysctl_lock(); 300 for (oidp = start; oidp < stop; oidp++) 301 sysctl_register_oid(*oidp); 302 sysctl_unlock(); 303 } 304 305 static void 306 linker_file_unregister_sysctls(linker_file_t lf) 307 { 308 struct sysctl_oid **start, **stop, **oidp; 309 310 KLD_DPF(FILE, ("linker_file_unregister_sysctls: registering SYSCTLs" 311 " for %s\n", lf->filename)); 312 313 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0) 314 return; 315 316 sysctl_lock(); 317 for (oidp = start; oidp < stop; oidp++) 318 sysctl_unregister_oid(*oidp); 319 sysctl_unlock(); 320 } 321 322 static int 323 linker_file_register_modules(linker_file_t lf) 324 { 325 struct mod_metadata **start, **stop, **mdp; 326 const moduledata_t *moddata; 327 int first_error, error; 328 329 KLD_DPF(FILE, ("linker_file_register_modules: registering modules" 330 " in %s\n", lf->filename)); 331 332 if (linker_file_lookup_set(lf, "modmetadata_set", &start, 333 &stop, NULL) != 0) { 334 /* 335 * This fallback should be unnecessary, but if we get booted 336 * from boot2 instead of loader and we are missing our 337 * metadata then we have to try the best we can. 338 */ 339 if (lf == linker_kernel_file) { 340 start = SET_BEGIN(modmetadata_set); 341 stop = SET_LIMIT(modmetadata_set); 342 } else 343 return (0); 344 } 345 first_error = 0; 346 for (mdp = start; mdp < stop; mdp++) { 347 if ((*mdp)->md_type != MDT_MODULE) 348 continue; 349 moddata = (*mdp)->md_data; 350 KLD_DPF(FILE, ("Registering module %s in %s\n", 351 moddata->name, lf->filename)); 352 error = module_register(moddata, lf); 353 if (error) { 354 printf("Module %s failed to register: %d\n", 355 moddata->name, error); 356 if (first_error == 0) 357 first_error = error; 358 } 359 } 360 return (first_error); 361 } 362 363 static void 364 linker_init_kernel_modules(void) 365 { 366 367 linker_file_register_modules(linker_kernel_file); 368 } 369 370 SYSINIT(linker_kernel, SI_SUB_KLD, SI_ORDER_ANY, linker_init_kernel_modules, 371 0); 372 373 static int 374 linker_load_file(const char *filename, linker_file_t *result) 375 { 376 linker_class_t lc; 377 linker_file_t lf; 378 int foundfile, error; 379 380 /* Refuse to load modules if securelevel raised */ 381 if (prison0.pr_securelevel > 0) 382 return (EPERM); 383 384 KLD_LOCK_ASSERT(); 385 lf = linker_find_file_by_name(filename); 386 if (lf) { 387 KLD_DPF(FILE, ("linker_load_file: file %s is already loaded," 388 " incrementing refs\n", filename)); 389 *result = lf; 390 lf->refs++; 391 return (0); 392 } 393 foundfile = 0; 394 error = 0; 395 396 /* 397 * We do not need to protect (lock) classes here because there is 398 * no class registration past startup (SI_SUB_KLD, SI_ORDER_ANY) 399 * and there is no class deregistration mechanism at this time. 400 */ 401 TAILQ_FOREACH(lc, &classes, link) { 402 KLD_DPF(FILE, ("linker_load_file: trying to load %s\n", 403 filename)); 404 error = LINKER_LOAD_FILE(lc, filename, &lf); 405 /* 406 * If we got something other than ENOENT, then it exists but 407 * we cannot load it for some other reason. 408 */ 409 if (error != ENOENT) 410 foundfile = 1; 411 if (lf) { 412 error = linker_file_register_modules(lf); 413 if (error == EEXIST) { 414 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 415 return (error); 416 } 417 KLD_UNLOCK(); 418 linker_file_register_sysctls(lf); 419 linker_file_sysinit(lf); 420 KLD_LOCK(); 421 lf->flags |= LINKER_FILE_LINKED; 422 *result = lf; 423 return (0); 424 } 425 } 426 /* 427 * Less than ideal, but tells the user whether it failed to load or 428 * the module was not found. 429 */ 430 if (foundfile) { 431 432 /* 433 * If the file type has not been recognized by the last try 434 * printout a message before to fail. 435 */ 436 if (error == ENOSYS) 437 printf("linker_load_file: Unsupported file type\n"); 438 439 /* 440 * Format not recognized or otherwise unloadable. 441 * When loading a module that is statically built into 442 * the kernel EEXIST percolates back up as the return 443 * value. Preserve this so that apps like sysinstall 444 * can recognize this special case and not post bogus 445 * dialog boxes. 446 */ 447 if (error != EEXIST) 448 error = ENOEXEC; 449 } else 450 error = ENOENT; /* Nothing found */ 451 return (error); 452 } 453 454 int 455 linker_reference_module(const char *modname, struct mod_depend *verinfo, 456 linker_file_t *result) 457 { 458 modlist_t mod; 459 int error; 460 461 KLD_LOCK(); 462 if ((mod = modlist_lookup2(modname, verinfo)) != NULL) { 463 *result = mod->container; 464 (*result)->refs++; 465 KLD_UNLOCK(); 466 return (0); 467 } 468 469 error = linker_load_module(NULL, modname, NULL, verinfo, result); 470 KLD_UNLOCK(); 471 return (error); 472 } 473 474 int 475 linker_release_module(const char *modname, struct mod_depend *verinfo, 476 linker_file_t lf) 477 { 478 modlist_t mod; 479 int error; 480 481 KLD_LOCK(); 482 if (lf == NULL) { 483 KASSERT(modname != NULL, 484 ("linker_release_module: no file or name")); 485 mod = modlist_lookup2(modname, verinfo); 486 if (mod == NULL) { 487 KLD_UNLOCK(); 488 return (ESRCH); 489 } 490 lf = mod->container; 491 } else 492 KASSERT(modname == NULL && verinfo == NULL, 493 ("linker_release_module: both file and name")); 494 error = linker_file_unload(lf, LINKER_UNLOAD_NORMAL); 495 KLD_UNLOCK(); 496 return (error); 497 } 498 499 static linker_file_t 500 linker_find_file_by_name(const char *filename) 501 { 502 linker_file_t lf; 503 char *koname; 504 505 koname = malloc(strlen(filename) + 4, M_LINKER, M_WAITOK); 506 sprintf(koname, "%s.ko", filename); 507 508 KLD_LOCK_ASSERT(); 509 TAILQ_FOREACH(lf, &linker_files, link) { 510 if (strcmp(lf->filename, koname) == 0) 511 break; 512 if (strcmp(lf->filename, filename) == 0) 513 break; 514 } 515 free(koname, M_LINKER); 516 return (lf); 517 } 518 519 static linker_file_t 520 linker_find_file_by_id(int fileid) 521 { 522 linker_file_t lf; 523 524 KLD_LOCK_ASSERT(); 525 TAILQ_FOREACH(lf, &linker_files, link) 526 if (lf->id == fileid && lf->flags & LINKER_FILE_LINKED) 527 break; 528 return (lf); 529 } 530 531 int 532 linker_file_foreach(linker_predicate_t *predicate, void *context) 533 { 534 linker_file_t lf; 535 int retval = 0; 536 537 KLD_LOCK(); 538 TAILQ_FOREACH(lf, &linker_files, link) { 539 retval = predicate(lf, context); 540 if (retval != 0) 541 break; 542 } 543 KLD_UNLOCK(); 544 return (retval); 545 } 546 547 linker_file_t 548 linker_make_file(const char *pathname, linker_class_t lc) 549 { 550 linker_file_t lf; 551 const char *filename; 552 553 KLD_LOCK_ASSERT(); 554 filename = linker_basename(pathname); 555 556 KLD_DPF(FILE, ("linker_make_file: new file, filename='%s' for pathname='%s'\n", filename, pathname)); 557 lf = (linker_file_t)kobj_create((kobj_class_t)lc, M_LINKER, M_WAITOK); 558 if (lf == NULL) 559 return (NULL); 560 lf->refs = 1; 561 lf->userrefs = 0; 562 lf->flags = 0; 563 lf->filename = linker_strdup(filename); 564 lf->pathname = linker_strdup(pathname); 565 LINKER_GET_NEXT_FILE_ID(lf->id); 566 lf->ndeps = 0; 567 lf->deps = NULL; 568 lf->loadcnt = ++loadcnt; 569 lf->sdt_probes = NULL; 570 lf->sdt_nprobes = 0; 571 STAILQ_INIT(&lf->common); 572 TAILQ_INIT(&lf->modules); 573 TAILQ_INSERT_TAIL(&linker_files, lf, link); 574 return (lf); 575 } 576 577 int 578 linker_file_unload(linker_file_t file, int flags) 579 { 580 module_t mod, next; 581 modlist_t ml, nextml; 582 struct common_symbol *cp; 583 int error, i; 584 585 /* Refuse to unload modules if securelevel raised. */ 586 if (prison0.pr_securelevel > 0) 587 return (EPERM); 588 589 KLD_LOCK_ASSERT(); 590 KLD_DPF(FILE, ("linker_file_unload: lf->refs=%d\n", file->refs)); 591 592 /* Easy case of just dropping a reference. */ 593 if (file->refs > 1) { 594 file->refs--; 595 return (0); 596 } 597 598 KLD_DPF(FILE, ("linker_file_unload: file is unloading," 599 " informing modules\n")); 600 601 /* 602 * Quiesce all the modules to give them a chance to veto the unload. 603 */ 604 MOD_SLOCK; 605 for (mod = TAILQ_FIRST(&file->modules); mod; 606 mod = module_getfnext(mod)) { 607 608 error = module_quiesce(mod); 609 if (error != 0 && flags != LINKER_UNLOAD_FORCE) { 610 KLD_DPF(FILE, ("linker_file_unload: module %s" 611 " vetoed unload\n", module_getname(mod))); 612 /* 613 * XXX: Do we need to tell all the quiesced modules 614 * that they can resume work now via a new module 615 * event? 616 */ 617 MOD_SUNLOCK; 618 return (error); 619 } 620 } 621 MOD_SUNLOCK; 622 623 /* 624 * Inform any modules associated with this file that they are 625 * being be unloaded. 626 */ 627 MOD_XLOCK; 628 for (mod = TAILQ_FIRST(&file->modules); mod; mod = next) { 629 next = module_getfnext(mod); 630 MOD_XUNLOCK; 631 632 /* 633 * Give the module a chance to veto the unload. 634 */ 635 if ((error = module_unload(mod)) != 0) { 636 KLD_DPF(FILE, ("linker_file_unload: module %s" 637 " failed unload\n", module_getname(mod))); 638 return (error); 639 } 640 MOD_XLOCK; 641 module_release(mod); 642 } 643 MOD_XUNLOCK; 644 645 TAILQ_FOREACH_SAFE(ml, &found_modules, link, nextml) { 646 if (ml->container == file) { 647 TAILQ_REMOVE(&found_modules, ml, link); 648 free(ml, M_LINKER); 649 } 650 } 651 652 /* 653 * Don't try to run SYSUNINITs if we are unloaded due to a 654 * link error. 655 */ 656 if (file->flags & LINKER_FILE_LINKED) { 657 file->flags &= ~LINKER_FILE_LINKED; 658 KLD_UNLOCK(); 659 linker_file_sysuninit(file); 660 linker_file_unregister_sysctls(file); 661 KLD_LOCK(); 662 } 663 TAILQ_REMOVE(&linker_files, file, link); 664 665 if (file->deps) { 666 for (i = 0; i < file->ndeps; i++) 667 linker_file_unload(file->deps[i], flags); 668 free(file->deps, M_LINKER); 669 file->deps = NULL; 670 } 671 while ((cp = STAILQ_FIRST(&file->common)) != NULL) { 672 STAILQ_REMOVE_HEAD(&file->common, link); 673 free(cp, M_LINKER); 674 } 675 676 LINKER_UNLOAD(file); 677 if (file->filename) { 678 free(file->filename, M_LINKER); 679 file->filename = NULL; 680 } 681 if (file->pathname) { 682 free(file->pathname, M_LINKER); 683 file->pathname = NULL; 684 } 685 kobj_delete((kobj_t) file, M_LINKER); 686 return (0); 687 } 688 689 int 690 linker_ctf_get(linker_file_t file, linker_ctf_t *lc) 691 { 692 return (LINKER_CTF_GET(file, lc)); 693 } 694 695 static int 696 linker_file_add_dependency(linker_file_t file, linker_file_t dep) 697 { 698 linker_file_t *newdeps; 699 700 KLD_LOCK_ASSERT(); 701 newdeps = malloc((file->ndeps + 1) * sizeof(linker_file_t *), 702 M_LINKER, M_WAITOK | M_ZERO); 703 if (newdeps == NULL) 704 return (ENOMEM); 705 706 if (file->deps) { 707 bcopy(file->deps, newdeps, 708 file->ndeps * sizeof(linker_file_t *)); 709 free(file->deps, M_LINKER); 710 } 711 file->deps = newdeps; 712 file->deps[file->ndeps] = dep; 713 file->ndeps++; 714 KLD_DPF(FILE, ("linker_file_add_dependency:" 715 " adding %s as dependency for %s\n", 716 dep->filename, file->filename)); 717 return (0); 718 } 719 720 /* 721 * Locate a linker set and its contents. This is a helper function to avoid 722 * linker_if.h exposure elsewhere. Note: firstp and lastp are really void **. 723 * This function is used in this file so we can avoid having lots of (void **) 724 * casts. 725 */ 726 int 727 linker_file_lookup_set(linker_file_t file, const char *name, 728 void *firstp, void *lastp, int *countp) 729 { 730 int error, locked; 731 732 locked = KLD_LOCKED(); 733 if (!locked) 734 KLD_LOCK(); 735 error = LINKER_LOOKUP_SET(file, name, firstp, lastp, countp); 736 if (!locked) 737 KLD_UNLOCK(); 738 return (error); 739 } 740 741 /* 742 * List all functions in a file. 743 */ 744 int 745 linker_file_function_listall(linker_file_t lf, 746 linker_function_nameval_callback_t callback_func, void *arg) 747 { 748 return (LINKER_EACH_FUNCTION_NAMEVAL(lf, callback_func, arg)); 749 } 750 751 caddr_t 752 linker_file_lookup_symbol(linker_file_t file, const char *name, int deps) 753 { 754 caddr_t sym; 755 int locked; 756 757 locked = KLD_LOCKED(); 758 if (!locked) 759 KLD_LOCK(); 760 sym = linker_file_lookup_symbol_internal(file, name, deps); 761 if (!locked) 762 KLD_UNLOCK(); 763 return (sym); 764 } 765 766 static caddr_t 767 linker_file_lookup_symbol_internal(linker_file_t file, const char *name, 768 int deps) 769 { 770 c_linker_sym_t sym; 771 linker_symval_t symval; 772 caddr_t address; 773 size_t common_size = 0; 774 int i; 775 776 KLD_LOCK_ASSERT(); 777 KLD_DPF(SYM, ("linker_file_lookup_symbol: file=%p, name=%s, deps=%d\n", 778 file, name, deps)); 779 780 if (LINKER_LOOKUP_SYMBOL(file, name, &sym) == 0) { 781 LINKER_SYMBOL_VALUES(file, sym, &symval); 782 if (symval.value == 0) 783 /* 784 * For commons, first look them up in the 785 * dependencies and only allocate space if not found 786 * there. 787 */ 788 common_size = symval.size; 789 else { 790 KLD_DPF(SYM, ("linker_file_lookup_symbol: symbol" 791 ".value=%p\n", symval.value)); 792 return (symval.value); 793 } 794 } 795 if (deps) { 796 for (i = 0; i < file->ndeps; i++) { 797 address = linker_file_lookup_symbol_internal( 798 file->deps[i], name, 0); 799 if (address) { 800 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 801 " deps value=%p\n", address)); 802 return (address); 803 } 804 } 805 } 806 if (common_size > 0) { 807 /* 808 * This is a common symbol which was not found in the 809 * dependencies. We maintain a simple common symbol table in 810 * the file object. 811 */ 812 struct common_symbol *cp; 813 814 STAILQ_FOREACH(cp, &file->common, link) { 815 if (strcmp(cp->name, name) == 0) { 816 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 817 " old common value=%p\n", cp->address)); 818 return (cp->address); 819 } 820 } 821 /* 822 * Round the symbol size up to align. 823 */ 824 common_size = (common_size + sizeof(int) - 1) & -sizeof(int); 825 cp = malloc(sizeof(struct common_symbol) 826 + common_size + strlen(name) + 1, M_LINKER, 827 M_WAITOK | M_ZERO); 828 cp->address = (caddr_t)(cp + 1); 829 cp->name = cp->address + common_size; 830 strcpy(cp->name, name); 831 bzero(cp->address, common_size); 832 STAILQ_INSERT_TAIL(&file->common, cp, link); 833 834 KLD_DPF(SYM, ("linker_file_lookup_symbol: new common" 835 " value=%p\n", cp->address)); 836 return (cp->address); 837 } 838 KLD_DPF(SYM, ("linker_file_lookup_symbol: fail\n")); 839 return (0); 840 } 841 842 /* 843 * Both DDB and stack(9) rely on the kernel linker to provide forward and 844 * backward lookup of symbols. However, DDB and sometimes stack(9) need to 845 * do this in a lockfree manner. We provide a set of internal helper 846 * routines to perform these operations without locks, and then wrappers that 847 * optionally lock. 848 * 849 * linker_debug_lookup() is ifdef DDB as currently it's only used by DDB. 850 */ 851 #ifdef DDB 852 static int 853 linker_debug_lookup(const char *symstr, c_linker_sym_t *sym) 854 { 855 linker_file_t lf; 856 857 TAILQ_FOREACH(lf, &linker_files, link) { 858 if (LINKER_LOOKUP_SYMBOL(lf, symstr, sym) == 0) 859 return (0); 860 } 861 return (ENOENT); 862 } 863 #endif 864 865 static int 866 linker_debug_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) 867 { 868 linker_file_t lf; 869 c_linker_sym_t best, es; 870 u_long diff, bestdiff, off; 871 872 best = 0; 873 off = (uintptr_t)value; 874 bestdiff = off; 875 TAILQ_FOREACH(lf, &linker_files, link) { 876 if (LINKER_SEARCH_SYMBOL(lf, value, &es, &diff) != 0) 877 continue; 878 if (es != 0 && diff < bestdiff) { 879 best = es; 880 bestdiff = diff; 881 } 882 if (bestdiff == 0) 883 break; 884 } 885 if (best) { 886 *sym = best; 887 *diffp = bestdiff; 888 return (0); 889 } else { 890 *sym = 0; 891 *diffp = off; 892 return (ENOENT); 893 } 894 } 895 896 static int 897 linker_debug_symbol_values(c_linker_sym_t sym, linker_symval_t *symval) 898 { 899 linker_file_t lf; 900 901 TAILQ_FOREACH(lf, &linker_files, link) { 902 if (LINKER_SYMBOL_VALUES(lf, sym, symval) == 0) 903 return (0); 904 } 905 return (ENOENT); 906 } 907 908 static int 909 linker_debug_search_symbol_name(caddr_t value, char *buf, u_int buflen, 910 long *offset) 911 { 912 linker_symval_t symval; 913 c_linker_sym_t sym; 914 int error; 915 916 *offset = 0; 917 error = linker_debug_search_symbol(value, &sym, offset); 918 if (error) 919 return (error); 920 error = linker_debug_symbol_values(sym, &symval); 921 if (error) 922 return (error); 923 strlcpy(buf, symval.name, buflen); 924 return (0); 925 } 926 927 /* 928 * DDB Helpers. DDB has to look across multiple files with their own symbol 929 * tables and string tables. 930 * 931 * Note that we do not obey list locking protocols here. We really don't need 932 * DDB to hang because somebody's got the lock held. We'll take the chance 933 * that the files list is inconsistant instead. 934 */ 935 #ifdef DDB 936 int 937 linker_ddb_lookup(const char *symstr, c_linker_sym_t *sym) 938 { 939 940 return (linker_debug_lookup(symstr, sym)); 941 } 942 #endif 943 944 int 945 linker_ddb_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) 946 { 947 948 return (linker_debug_search_symbol(value, sym, diffp)); 949 } 950 951 int 952 linker_ddb_symbol_values(c_linker_sym_t sym, linker_symval_t *symval) 953 { 954 955 return (linker_debug_symbol_values(sym, symval)); 956 } 957 958 int 959 linker_ddb_search_symbol_name(caddr_t value, char *buf, u_int buflen, 960 long *offset) 961 { 962 963 return (linker_debug_search_symbol_name(value, buf, buflen, offset)); 964 } 965 966 /* 967 * stack(9) helper for non-debugging environemnts. Unlike DDB helpers, we do 968 * obey locking protocols, and offer a significantly less complex interface. 969 */ 970 int 971 linker_search_symbol_name(caddr_t value, char *buf, u_int buflen, 972 long *offset) 973 { 974 int error; 975 976 KLD_LOCK(); 977 error = linker_debug_search_symbol_name(value, buf, buflen, offset); 978 KLD_UNLOCK(); 979 return (error); 980 } 981 982 /* 983 * Syscalls. 984 */ 985 int 986 kern_kldload(struct thread *td, const char *file, int *fileid) 987 { 988 #ifdef HWPMC_HOOKS 989 struct pmckern_map_in pkm; 990 #endif 991 const char *kldname, *modname; 992 linker_file_t lf; 993 int error; 994 995 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 996 return (error); 997 998 if ((error = priv_check(td, PRIV_KLD_LOAD)) != 0) 999 return (error); 1000 1001 /* 1002 * It is possible that kldloaded module will attach a new ifnet, 1003 * so vnet context must be set when this ocurs. 1004 */ 1005 CURVNET_SET(TD_TO_VNET(td)); 1006 1007 /* 1008 * If file does not contain a qualified name or any dot in it 1009 * (kldname.ko, or kldname.ver.ko) treat it as an interface 1010 * name. 1011 */ 1012 if (index(file, '/') || index(file, '.')) { 1013 kldname = file; 1014 modname = NULL; 1015 } else { 1016 kldname = NULL; 1017 modname = file; 1018 } 1019 1020 KLD_LOCK(); 1021 error = linker_load_module(kldname, modname, NULL, NULL, &lf); 1022 if (error) 1023 goto unlock; 1024 #ifdef HWPMC_HOOKS 1025 pkm.pm_file = lf->filename; 1026 pkm.pm_address = (uintptr_t) lf->address; 1027 PMC_CALL_HOOK(td, PMC_FN_KLD_LOAD, (void *) &pkm); 1028 #endif 1029 lf->userrefs++; 1030 if (fileid != NULL) 1031 *fileid = lf->id; 1032 unlock: 1033 KLD_UNLOCK(); 1034 CURVNET_RESTORE(); 1035 return (error); 1036 } 1037 1038 int 1039 kldload(struct thread *td, struct kldload_args *uap) 1040 { 1041 char *pathname = NULL; 1042 int error, fileid; 1043 1044 td->td_retval[0] = -1; 1045 1046 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1047 error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL); 1048 if (error == 0) { 1049 error = kern_kldload(td, pathname, &fileid); 1050 if (error == 0) 1051 td->td_retval[0] = fileid; 1052 } 1053 free(pathname, M_TEMP); 1054 return (error); 1055 } 1056 1057 int 1058 kern_kldunload(struct thread *td, int fileid, int flags) 1059 { 1060 #ifdef HWPMC_HOOKS 1061 struct pmckern_map_out pkm; 1062 #endif 1063 linker_file_t lf; 1064 int error = 0; 1065 1066 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 1067 return (error); 1068 1069 if ((error = priv_check(td, PRIV_KLD_UNLOAD)) != 0) 1070 return (error); 1071 1072 CURVNET_SET(TD_TO_VNET(td)); 1073 KLD_LOCK(); 1074 lf = linker_find_file_by_id(fileid); 1075 if (lf) { 1076 KLD_DPF(FILE, ("kldunload: lf->userrefs=%d\n", lf->userrefs)); 1077 1078 /* Check if there are DTrace probes enabled on this file. */ 1079 if (lf->nenabled > 0) { 1080 printf("kldunload: attempt to unload file that has" 1081 " DTrace probes enabled\n"); 1082 error = EBUSY; 1083 } else if (lf->userrefs == 0) { 1084 /* 1085 * XXX: maybe LINKER_UNLOAD_FORCE should override ? 1086 */ 1087 printf("kldunload: attempt to unload file that was" 1088 " loaded by the kernel\n"); 1089 error = EBUSY; 1090 } else { 1091 #ifdef HWPMC_HOOKS 1092 /* Save data needed by hwpmc(4) before unloading. */ 1093 pkm.pm_address = (uintptr_t) lf->address; 1094 pkm.pm_size = lf->size; 1095 #endif 1096 lf->userrefs--; 1097 error = linker_file_unload(lf, flags); 1098 if (error) 1099 lf->userrefs++; 1100 } 1101 } else 1102 error = ENOENT; 1103 1104 #ifdef HWPMC_HOOKS 1105 if (error == 0) 1106 PMC_CALL_HOOK(td, PMC_FN_KLD_UNLOAD, (void *) &pkm); 1107 #endif 1108 KLD_UNLOCK(); 1109 CURVNET_RESTORE(); 1110 return (error); 1111 } 1112 1113 int 1114 kldunload(struct thread *td, struct kldunload_args *uap) 1115 { 1116 1117 return (kern_kldunload(td, uap->fileid, LINKER_UNLOAD_NORMAL)); 1118 } 1119 1120 int 1121 kldunloadf(struct thread *td, struct kldunloadf_args *uap) 1122 { 1123 1124 if (uap->flags != LINKER_UNLOAD_NORMAL && 1125 uap->flags != LINKER_UNLOAD_FORCE) 1126 return (EINVAL); 1127 return (kern_kldunload(td, uap->fileid, uap->flags)); 1128 } 1129 1130 int 1131 kldfind(struct thread *td, struct kldfind_args *uap) 1132 { 1133 char *pathname; 1134 const char *filename; 1135 linker_file_t lf; 1136 int error; 1137 1138 #ifdef MAC 1139 error = mac_kld_check_stat(td->td_ucred); 1140 if (error) 1141 return (error); 1142 #endif 1143 1144 td->td_retval[0] = -1; 1145 1146 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1147 if ((error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL)) != 0) 1148 goto out; 1149 1150 filename = linker_basename(pathname); 1151 KLD_LOCK(); 1152 lf = linker_find_file_by_name(filename); 1153 if (lf) 1154 td->td_retval[0] = lf->id; 1155 else 1156 error = ENOENT; 1157 KLD_UNLOCK(); 1158 out: 1159 free(pathname, M_TEMP); 1160 return (error); 1161 } 1162 1163 int 1164 kldnext(struct thread *td, struct kldnext_args *uap) 1165 { 1166 linker_file_t lf; 1167 int error = 0; 1168 1169 #ifdef MAC 1170 error = mac_kld_check_stat(td->td_ucred); 1171 if (error) 1172 return (error); 1173 #endif 1174 1175 KLD_LOCK(); 1176 if (uap->fileid == 0) 1177 lf = TAILQ_FIRST(&linker_files); 1178 else { 1179 lf = linker_find_file_by_id(uap->fileid); 1180 if (lf == NULL) { 1181 error = ENOENT; 1182 goto out; 1183 } 1184 lf = TAILQ_NEXT(lf, link); 1185 } 1186 1187 /* Skip partially loaded files. */ 1188 while (lf != NULL && !(lf->flags & LINKER_FILE_LINKED)) 1189 lf = TAILQ_NEXT(lf, link); 1190 1191 if (lf) 1192 td->td_retval[0] = lf->id; 1193 else 1194 td->td_retval[0] = 0; 1195 out: 1196 KLD_UNLOCK(); 1197 return (error); 1198 } 1199 1200 int 1201 kldstat(struct thread *td, struct kldstat_args *uap) 1202 { 1203 struct kld_file_stat stat; 1204 linker_file_t lf; 1205 int error, namelen, version, version_num; 1206 1207 /* 1208 * Check the version of the user's structure. 1209 */ 1210 if ((error = copyin(&uap->stat->version, &version, sizeof(version))) != 0) 1211 return (error); 1212 if (version == sizeof(struct kld_file_stat_1)) 1213 version_num = 1; 1214 else if (version == sizeof(struct kld_file_stat)) 1215 version_num = 2; 1216 else 1217 return (EINVAL); 1218 1219 #ifdef MAC 1220 error = mac_kld_check_stat(td->td_ucred); 1221 if (error) 1222 return (error); 1223 #endif 1224 1225 KLD_LOCK(); 1226 lf = linker_find_file_by_id(uap->fileid); 1227 if (lf == NULL) { 1228 KLD_UNLOCK(); 1229 return (ENOENT); 1230 } 1231 1232 /* Version 1 fields: */ 1233 namelen = strlen(lf->filename) + 1; 1234 if (namelen > MAXPATHLEN) 1235 namelen = MAXPATHLEN; 1236 bcopy(lf->filename, &stat.name[0], namelen); 1237 stat.refs = lf->refs; 1238 stat.id = lf->id; 1239 stat.address = lf->address; 1240 stat.size = lf->size; 1241 if (version_num > 1) { 1242 /* Version 2 fields: */ 1243 namelen = strlen(lf->pathname) + 1; 1244 if (namelen > MAXPATHLEN) 1245 namelen = MAXPATHLEN; 1246 bcopy(lf->pathname, &stat.pathname[0], namelen); 1247 } 1248 KLD_UNLOCK(); 1249 1250 td->td_retval[0] = 0; 1251 1252 return (copyout(&stat, uap->stat, version)); 1253 } 1254 1255 int 1256 kldfirstmod(struct thread *td, struct kldfirstmod_args *uap) 1257 { 1258 linker_file_t lf; 1259 module_t mp; 1260 int error = 0; 1261 1262 #ifdef MAC 1263 error = mac_kld_check_stat(td->td_ucred); 1264 if (error) 1265 return (error); 1266 #endif 1267 1268 KLD_LOCK(); 1269 lf = linker_find_file_by_id(uap->fileid); 1270 if (lf) { 1271 MOD_SLOCK; 1272 mp = TAILQ_FIRST(&lf->modules); 1273 if (mp != NULL) 1274 td->td_retval[0] = module_getid(mp); 1275 else 1276 td->td_retval[0] = 0; 1277 MOD_SUNLOCK; 1278 } else 1279 error = ENOENT; 1280 KLD_UNLOCK(); 1281 return (error); 1282 } 1283 1284 int 1285 kldsym(struct thread *td, struct kldsym_args *uap) 1286 { 1287 char *symstr = NULL; 1288 c_linker_sym_t sym; 1289 linker_symval_t symval; 1290 linker_file_t lf; 1291 struct kld_sym_lookup lookup; 1292 int error = 0; 1293 1294 #ifdef MAC 1295 error = mac_kld_check_stat(td->td_ucred); 1296 if (error) 1297 return (error); 1298 #endif 1299 1300 if ((error = copyin(uap->data, &lookup, sizeof(lookup))) != 0) 1301 return (error); 1302 if (lookup.version != sizeof(lookup) || 1303 uap->cmd != KLDSYM_LOOKUP) 1304 return (EINVAL); 1305 symstr = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1306 if ((error = copyinstr(lookup.symname, symstr, MAXPATHLEN, NULL)) != 0) 1307 goto out; 1308 KLD_LOCK(); 1309 if (uap->fileid != 0) { 1310 lf = linker_find_file_by_id(uap->fileid); 1311 if (lf == NULL) 1312 error = ENOENT; 1313 else if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 1314 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 1315 lookup.symvalue = (uintptr_t) symval.value; 1316 lookup.symsize = symval.size; 1317 error = copyout(&lookup, uap->data, sizeof(lookup)); 1318 } else 1319 error = ENOENT; 1320 } else { 1321 TAILQ_FOREACH(lf, &linker_files, link) { 1322 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 1323 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 1324 lookup.symvalue = (uintptr_t)symval.value; 1325 lookup.symsize = symval.size; 1326 error = copyout(&lookup, uap->data, 1327 sizeof(lookup)); 1328 break; 1329 } 1330 } 1331 if (lf == NULL) 1332 error = ENOENT; 1333 } 1334 KLD_UNLOCK(); 1335 out: 1336 free(symstr, M_TEMP); 1337 return (error); 1338 } 1339 1340 /* 1341 * Preloaded module support 1342 */ 1343 1344 static modlist_t 1345 modlist_lookup(const char *name, int ver) 1346 { 1347 modlist_t mod; 1348 1349 TAILQ_FOREACH(mod, &found_modules, link) { 1350 if (strcmp(mod->name, name) == 0 && 1351 (ver == 0 || mod->version == ver)) 1352 return (mod); 1353 } 1354 return (NULL); 1355 } 1356 1357 static modlist_t 1358 modlist_lookup2(const char *name, struct mod_depend *verinfo) 1359 { 1360 modlist_t mod, bestmod; 1361 int ver; 1362 1363 if (verinfo == NULL) 1364 return (modlist_lookup(name, 0)); 1365 bestmod = NULL; 1366 TAILQ_FOREACH(mod, &found_modules, link) { 1367 if (strcmp(mod->name, name) != 0) 1368 continue; 1369 ver = mod->version; 1370 if (ver == verinfo->md_ver_preferred) 1371 return (mod); 1372 if (ver >= verinfo->md_ver_minimum && 1373 ver <= verinfo->md_ver_maximum && 1374 (bestmod == NULL || ver > bestmod->version)) 1375 bestmod = mod; 1376 } 1377 return (bestmod); 1378 } 1379 1380 static modlist_t 1381 modlist_newmodule(const char *modname, int version, linker_file_t container) 1382 { 1383 modlist_t mod; 1384 1385 mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT | M_ZERO); 1386 if (mod == NULL) 1387 panic("no memory for module list"); 1388 mod->container = container; 1389 mod->name = modname; 1390 mod->version = version; 1391 TAILQ_INSERT_TAIL(&found_modules, mod, link); 1392 return (mod); 1393 } 1394 1395 static void 1396 linker_addmodules(linker_file_t lf, struct mod_metadata **start, 1397 struct mod_metadata **stop, int preload) 1398 { 1399 struct mod_metadata *mp, **mdp; 1400 const char *modname; 1401 int ver; 1402 1403 for (mdp = start; mdp < stop; mdp++) { 1404 mp = *mdp; 1405 if (mp->md_type != MDT_VERSION) 1406 continue; 1407 modname = mp->md_cval; 1408 ver = ((struct mod_version *)mp->md_data)->mv_version; 1409 if (modlist_lookup(modname, ver) != NULL) { 1410 printf("module %s already present!\n", modname); 1411 /* XXX what can we do? this is a build error. :-( */ 1412 continue; 1413 } 1414 modlist_newmodule(modname, ver, lf); 1415 } 1416 } 1417 1418 static void 1419 linker_preload(void *arg) 1420 { 1421 caddr_t modptr; 1422 const char *modname, *nmodname; 1423 char *modtype; 1424 linker_file_t lf, nlf; 1425 linker_class_t lc; 1426 int error; 1427 linker_file_list_t loaded_files; 1428 linker_file_list_t depended_files; 1429 struct mod_metadata *mp, *nmp; 1430 struct mod_metadata **start, **stop, **mdp, **nmdp; 1431 struct mod_depend *verinfo; 1432 int nver; 1433 int resolves; 1434 modlist_t mod; 1435 struct sysinit **si_start, **si_stop; 1436 1437 TAILQ_INIT(&loaded_files); 1438 TAILQ_INIT(&depended_files); 1439 TAILQ_INIT(&found_modules); 1440 error = 0; 1441 1442 modptr = NULL; 1443 while ((modptr = preload_search_next_name(modptr)) != NULL) { 1444 modname = (char *)preload_search_info(modptr, MODINFO_NAME); 1445 modtype = (char *)preload_search_info(modptr, MODINFO_TYPE); 1446 if (modname == NULL) { 1447 printf("Preloaded module at %p does not have a" 1448 " name!\n", modptr); 1449 continue; 1450 } 1451 if (modtype == NULL) { 1452 printf("Preloaded module at %p does not have a type!\n", 1453 modptr); 1454 continue; 1455 } 1456 if (bootverbose) 1457 printf("Preloaded %s \"%s\" at %p.\n", modtype, modname, 1458 modptr); 1459 lf = NULL; 1460 TAILQ_FOREACH(lc, &classes, link) { 1461 error = LINKER_LINK_PRELOAD(lc, modname, &lf); 1462 if (!error) 1463 break; 1464 lf = NULL; 1465 } 1466 if (lf) 1467 TAILQ_INSERT_TAIL(&loaded_files, lf, loaded); 1468 } 1469 1470 /* 1471 * First get a list of stuff in the kernel. 1472 */ 1473 if (linker_file_lookup_set(linker_kernel_file, MDT_SETNAME, &start, 1474 &stop, NULL) == 0) 1475 linker_addmodules(linker_kernel_file, start, stop, 1); 1476 1477 /* 1478 * This is a once-off kinky bubble sort to resolve relocation 1479 * dependency requirements. 1480 */ 1481 restart: 1482 TAILQ_FOREACH(lf, &loaded_files, loaded) { 1483 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1484 &stop, NULL); 1485 /* 1486 * First, look to see if we would successfully link with this 1487 * stuff. 1488 */ 1489 resolves = 1; /* unless we know otherwise */ 1490 if (!error) { 1491 for (mdp = start; mdp < stop; mdp++) { 1492 mp = *mdp; 1493 if (mp->md_type != MDT_DEPEND) 1494 continue; 1495 modname = mp->md_cval; 1496 verinfo = mp->md_data; 1497 for (nmdp = start; nmdp < stop; nmdp++) { 1498 nmp = *nmdp; 1499 if (nmp->md_type != MDT_VERSION) 1500 continue; 1501 nmodname = nmp->md_cval; 1502 if (strcmp(modname, nmodname) == 0) 1503 break; 1504 } 1505 if (nmdp < stop) /* it's a self reference */ 1506 continue; 1507 1508 /* 1509 * ok, the module isn't here yet, we 1510 * are not finished 1511 */ 1512 if (modlist_lookup2(modname, verinfo) == NULL) 1513 resolves = 0; 1514 } 1515 } 1516 /* 1517 * OK, if we found our modules, we can link. So, "provide" 1518 * the modules inside and add it to the end of the link order 1519 * list. 1520 */ 1521 if (resolves) { 1522 if (!error) { 1523 for (mdp = start; mdp < stop; mdp++) { 1524 mp = *mdp; 1525 if (mp->md_type != MDT_VERSION) 1526 continue; 1527 modname = mp->md_cval; 1528 nver = ((struct mod_version *) 1529 mp->md_data)->mv_version; 1530 if (modlist_lookup(modname, 1531 nver) != NULL) { 1532 printf("module %s already" 1533 " present!\n", modname); 1534 TAILQ_REMOVE(&loaded_files, 1535 lf, loaded); 1536 linker_file_unload(lf, 1537 LINKER_UNLOAD_FORCE); 1538 /* we changed tailq next ptr */ 1539 goto restart; 1540 } 1541 modlist_newmodule(modname, nver, lf); 1542 } 1543 } 1544 TAILQ_REMOVE(&loaded_files, lf, loaded); 1545 TAILQ_INSERT_TAIL(&depended_files, lf, loaded); 1546 /* 1547 * Since we provided modules, we need to restart the 1548 * sort so that the previous files that depend on us 1549 * have a chance. Also, we've busted the tailq next 1550 * pointer with the REMOVE. 1551 */ 1552 goto restart; 1553 } 1554 } 1555 1556 /* 1557 * At this point, we check to see what could not be resolved.. 1558 */ 1559 while ((lf = TAILQ_FIRST(&loaded_files)) != NULL) { 1560 TAILQ_REMOVE(&loaded_files, lf, loaded); 1561 printf("KLD file %s is missing dependencies\n", lf->filename); 1562 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1563 } 1564 1565 /* 1566 * We made it. Finish off the linking in the order we determined. 1567 */ 1568 TAILQ_FOREACH_SAFE(lf, &depended_files, loaded, nlf) { 1569 if (linker_kernel_file) { 1570 linker_kernel_file->refs++; 1571 error = linker_file_add_dependency(lf, 1572 linker_kernel_file); 1573 if (error) 1574 panic("cannot add dependency"); 1575 } 1576 lf->userrefs++; /* so we can (try to) kldunload it */ 1577 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1578 &stop, NULL); 1579 if (!error) { 1580 for (mdp = start; mdp < stop; mdp++) { 1581 mp = *mdp; 1582 if (mp->md_type != MDT_DEPEND) 1583 continue; 1584 modname = mp->md_cval; 1585 verinfo = mp->md_data; 1586 mod = modlist_lookup2(modname, verinfo); 1587 /* Don't count self-dependencies */ 1588 if (lf == mod->container) 1589 continue; 1590 mod->container->refs++; 1591 error = linker_file_add_dependency(lf, 1592 mod->container); 1593 if (error) 1594 panic("cannot add dependency"); 1595 } 1596 } 1597 /* 1598 * Now do relocation etc using the symbol search paths 1599 * established by the dependencies 1600 */ 1601 error = LINKER_LINK_PRELOAD_FINISH(lf); 1602 if (error) { 1603 TAILQ_REMOVE(&depended_files, lf, loaded); 1604 printf("KLD file %s - could not finalize loading\n", 1605 lf->filename); 1606 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1607 continue; 1608 } 1609 linker_file_register_modules(lf); 1610 if (linker_file_lookup_set(lf, "sysinit_set", &si_start, 1611 &si_stop, NULL) == 0) 1612 sysinit_add(si_start, si_stop); 1613 linker_file_register_sysctls(lf); 1614 lf->flags |= LINKER_FILE_LINKED; 1615 } 1616 /* woohoo! we made it! */ 1617 } 1618 1619 SYSINIT(preload, SI_SUB_KLD, SI_ORDER_MIDDLE, linker_preload, 0); 1620 1621 /* 1622 * Search for a not-loaded module by name. 1623 * 1624 * Modules may be found in the following locations: 1625 * 1626 * - preloaded (result is just the module name) - on disk (result is full path 1627 * to module) 1628 * 1629 * If the module name is qualified in any way (contains path, etc.) the we 1630 * simply return a copy of it. 1631 * 1632 * The search path can be manipulated via sysctl. Note that we use the ';' 1633 * character as a separator to be consistent with the bootloader. 1634 */ 1635 1636 static char linker_hintfile[] = "linker.hints"; 1637 static char linker_path[MAXPATHLEN] = "/boot/kernel;/boot/modules"; 1638 1639 SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RW, linker_path, 1640 sizeof(linker_path), "module load search path"); 1641 1642 TUNABLE_STR("module_path", linker_path, sizeof(linker_path)); 1643 1644 static char *linker_ext_list[] = { 1645 "", 1646 ".ko", 1647 NULL 1648 }; 1649 1650 /* 1651 * Check if file actually exists either with or without extension listed in 1652 * the linker_ext_list. (probably should be generic for the rest of the 1653 * kernel) 1654 */ 1655 static char * 1656 linker_lookup_file(const char *path, int pathlen, const char *name, 1657 int namelen, struct vattr *vap) 1658 { 1659 struct nameidata nd; 1660 struct thread *td = curthread; /* XXX */ 1661 char *result, **cpp, *sep; 1662 int error, len, extlen, reclen, flags, vfslocked; 1663 enum vtype type; 1664 1665 extlen = 0; 1666 for (cpp = linker_ext_list; *cpp; cpp++) { 1667 len = strlen(*cpp); 1668 if (len > extlen) 1669 extlen = len; 1670 } 1671 extlen++; /* trailing '\0' */ 1672 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1673 1674 reclen = pathlen + strlen(sep) + namelen + extlen + 1; 1675 result = malloc(reclen, M_LINKER, M_WAITOK); 1676 for (cpp = linker_ext_list; *cpp; cpp++) { 1677 snprintf(result, reclen, "%.*s%s%.*s%s", pathlen, path, sep, 1678 namelen, name, *cpp); 1679 /* 1680 * Attempt to open the file, and return the path if 1681 * we succeed and it's a regular file. 1682 */ 1683 NDINIT(&nd, LOOKUP, FOLLOW | MPSAFE, UIO_SYSSPACE, result, td); 1684 flags = FREAD; 1685 error = vn_open(&nd, &flags, 0, NULL); 1686 if (error == 0) { 1687 vfslocked = NDHASGIANT(&nd); 1688 NDFREE(&nd, NDF_ONLY_PNBUF); 1689 type = nd.ni_vp->v_type; 1690 if (vap) 1691 VOP_GETATTR(nd.ni_vp, vap, td->td_ucred); 1692 VOP_UNLOCK(nd.ni_vp, 0); 1693 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 1694 VFS_UNLOCK_GIANT(vfslocked); 1695 if (type == VREG) 1696 return (result); 1697 } 1698 } 1699 free(result, M_LINKER); 1700 return (NULL); 1701 } 1702 1703 #define INT_ALIGN(base, ptr) ptr = \ 1704 (base) + (((ptr) - (base) + sizeof(int) - 1) & ~(sizeof(int) - 1)) 1705 1706 /* 1707 * Lookup KLD which contains requested module in the "linker.hints" file. If 1708 * version specification is available, then try to find the best KLD. 1709 * Otherwise just find the latest one. 1710 */ 1711 static char * 1712 linker_hints_lookup(const char *path, int pathlen, const char *modname, 1713 int modnamelen, struct mod_depend *verinfo) 1714 { 1715 struct thread *td = curthread; /* XXX */ 1716 struct ucred *cred = td ? td->td_ucred : NULL; 1717 struct nameidata nd; 1718 struct vattr vattr, mattr; 1719 u_char *hints = NULL; 1720 u_char *cp, *recptr, *bufend, *result, *best, *pathbuf, *sep; 1721 int error, ival, bestver, *intp, reclen, found, flags, clen, blen; 1722 int vfslocked = 0; 1723 1724 result = NULL; 1725 bestver = found = 0; 1726 1727 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1728 reclen = imax(modnamelen, strlen(linker_hintfile)) + pathlen + 1729 strlen(sep) + 1; 1730 pathbuf = malloc(reclen, M_LINKER, M_WAITOK); 1731 snprintf(pathbuf, reclen, "%.*s%s%s", pathlen, path, sep, 1732 linker_hintfile); 1733 1734 NDINIT(&nd, LOOKUP, NOFOLLOW | MPSAFE, UIO_SYSSPACE, pathbuf, td); 1735 flags = FREAD; 1736 error = vn_open(&nd, &flags, 0, NULL); 1737 if (error) 1738 goto bad; 1739 vfslocked = NDHASGIANT(&nd); 1740 NDFREE(&nd, NDF_ONLY_PNBUF); 1741 if (nd.ni_vp->v_type != VREG) 1742 goto bad; 1743 best = cp = NULL; 1744 error = VOP_GETATTR(nd.ni_vp, &vattr, cred); 1745 if (error) 1746 goto bad; 1747 /* 1748 * XXX: we need to limit this number to some reasonable value 1749 */ 1750 if (vattr.va_size > 100 * 1024) { 1751 printf("hints file too large %ld\n", (long)vattr.va_size); 1752 goto bad; 1753 } 1754 hints = malloc(vattr.va_size, M_TEMP, M_WAITOK); 1755 if (hints == NULL) 1756 goto bad; 1757 error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)hints, vattr.va_size, 0, 1758 UIO_SYSSPACE, IO_NODELOCKED, cred, NOCRED, &reclen, td); 1759 if (error) 1760 goto bad; 1761 VOP_UNLOCK(nd.ni_vp, 0); 1762 vn_close(nd.ni_vp, FREAD, cred, td); 1763 VFS_UNLOCK_GIANT(vfslocked); 1764 nd.ni_vp = NULL; 1765 if (reclen != 0) { 1766 printf("can't read %d\n", reclen); 1767 goto bad; 1768 } 1769 intp = (int *)hints; 1770 ival = *intp++; 1771 if (ival != LINKER_HINTS_VERSION) { 1772 printf("hints file version mismatch %d\n", ival); 1773 goto bad; 1774 } 1775 bufend = hints + vattr.va_size; 1776 recptr = (u_char *)intp; 1777 clen = blen = 0; 1778 while (recptr < bufend && !found) { 1779 intp = (int *)recptr; 1780 reclen = *intp++; 1781 ival = *intp++; 1782 cp = (char *)intp; 1783 switch (ival) { 1784 case MDT_VERSION: 1785 clen = *cp++; 1786 if (clen != modnamelen || bcmp(cp, modname, clen) != 0) 1787 break; 1788 cp += clen; 1789 INT_ALIGN(hints, cp); 1790 ival = *(int *)cp; 1791 cp += sizeof(int); 1792 clen = *cp++; 1793 if (verinfo == NULL || 1794 ival == verinfo->md_ver_preferred) { 1795 found = 1; 1796 break; 1797 } 1798 if (ival >= verinfo->md_ver_minimum && 1799 ival <= verinfo->md_ver_maximum && 1800 ival > bestver) { 1801 bestver = ival; 1802 best = cp; 1803 blen = clen; 1804 } 1805 break; 1806 default: 1807 break; 1808 } 1809 recptr += reclen + sizeof(int); 1810 } 1811 /* 1812 * Finally check if KLD is in the place 1813 */ 1814 if (found) 1815 result = linker_lookup_file(path, pathlen, cp, clen, &mattr); 1816 else if (best) 1817 result = linker_lookup_file(path, pathlen, best, blen, &mattr); 1818 1819 /* 1820 * KLD is newer than hints file. What we should do now? 1821 */ 1822 if (result && timespeccmp(&mattr.va_mtime, &vattr.va_mtime, >)) 1823 printf("warning: KLD '%s' is newer than the linker.hints" 1824 " file\n", result); 1825 bad: 1826 free(pathbuf, M_LINKER); 1827 if (hints) 1828 free(hints, M_TEMP); 1829 if (nd.ni_vp != NULL) { 1830 VOP_UNLOCK(nd.ni_vp, 0); 1831 vn_close(nd.ni_vp, FREAD, cred, td); 1832 VFS_UNLOCK_GIANT(vfslocked); 1833 } 1834 /* 1835 * If nothing found or hints is absent - fallback to the old 1836 * way by using "kldname[.ko]" as module name. 1837 */ 1838 if (!found && !bestver && result == NULL) 1839 result = linker_lookup_file(path, pathlen, modname, 1840 modnamelen, NULL); 1841 return (result); 1842 } 1843 1844 /* 1845 * Lookup KLD which contains requested module in the all directories. 1846 */ 1847 static char * 1848 linker_search_module(const char *modname, int modnamelen, 1849 struct mod_depend *verinfo) 1850 { 1851 char *cp, *ep, *result; 1852 1853 /* 1854 * traverse the linker path 1855 */ 1856 for (cp = linker_path; *cp; cp = ep + 1) { 1857 /* find the end of this component */ 1858 for (ep = cp; (*ep != 0) && (*ep != ';'); ep++); 1859 result = linker_hints_lookup(cp, ep - cp, modname, 1860 modnamelen, verinfo); 1861 if (result != NULL) 1862 return (result); 1863 if (*ep == 0) 1864 break; 1865 } 1866 return (NULL); 1867 } 1868 1869 /* 1870 * Search for module in all directories listed in the linker_path. 1871 */ 1872 static char * 1873 linker_search_kld(const char *name) 1874 { 1875 char *cp, *ep, *result; 1876 int len; 1877 1878 /* qualified at all? */ 1879 if (index(name, '/')) 1880 return (linker_strdup(name)); 1881 1882 /* traverse the linker path */ 1883 len = strlen(name); 1884 for (ep = linker_path; *ep; ep++) { 1885 cp = ep; 1886 /* find the end of this component */ 1887 for (; *ep != 0 && *ep != ';'; ep++); 1888 result = linker_lookup_file(cp, ep - cp, name, len, NULL); 1889 if (result != NULL) 1890 return (result); 1891 } 1892 return (NULL); 1893 } 1894 1895 static const char * 1896 linker_basename(const char *path) 1897 { 1898 const char *filename; 1899 1900 filename = rindex(path, '/'); 1901 if (filename == NULL) 1902 return path; 1903 if (filename[1]) 1904 filename++; 1905 return (filename); 1906 } 1907 1908 #ifdef HWPMC_HOOKS 1909 /* 1910 * Inform hwpmc about the set of kernel modules currently loaded. 1911 */ 1912 void * 1913 linker_hwpmc_list_objects(void) 1914 { 1915 linker_file_t lf; 1916 struct pmckern_map_in *kobase; 1917 int i, nmappings; 1918 1919 nmappings = 0; 1920 KLD_LOCK(); 1921 TAILQ_FOREACH(lf, &linker_files, link) 1922 nmappings++; 1923 1924 /* Allocate nmappings + 1 entries. */ 1925 kobase = malloc((nmappings + 1) * sizeof(struct pmckern_map_in), 1926 M_LINKER, M_WAITOK | M_ZERO); 1927 i = 0; 1928 TAILQ_FOREACH(lf, &linker_files, link) { 1929 1930 /* Save the info for this linker file. */ 1931 kobase[i].pm_file = lf->filename; 1932 kobase[i].pm_address = (uintptr_t)lf->address; 1933 i++; 1934 } 1935 KLD_UNLOCK(); 1936 1937 KASSERT(i > 0, ("linker_hpwmc_list_objects: no kernel objects?")); 1938 1939 /* The last entry of the malloced area comprises of all zeros. */ 1940 KASSERT(kobase[i].pm_file == NULL, 1941 ("linker_hwpmc_list_objects: last object not NULL")); 1942 1943 return ((void *)kobase); 1944 } 1945 #endif 1946 1947 /* 1948 * Find a file which contains given module and load it, if "parent" is not 1949 * NULL, register a reference to it. 1950 */ 1951 static int 1952 linker_load_module(const char *kldname, const char *modname, 1953 struct linker_file *parent, struct mod_depend *verinfo, 1954 struct linker_file **lfpp) 1955 { 1956 linker_file_t lfdep; 1957 const char *filename; 1958 char *pathname; 1959 int error; 1960 1961 KLD_LOCK_ASSERT(); 1962 if (modname == NULL) { 1963 /* 1964 * We have to load KLD 1965 */ 1966 KASSERT(verinfo == NULL, ("linker_load_module: verinfo" 1967 " is not NULL")); 1968 pathname = linker_search_kld(kldname); 1969 } else { 1970 if (modlist_lookup2(modname, verinfo) != NULL) 1971 return (EEXIST); 1972 if (kldname != NULL) 1973 pathname = linker_strdup(kldname); 1974 else if (rootvnode == NULL) 1975 pathname = NULL; 1976 else 1977 /* 1978 * Need to find a KLD with required module 1979 */ 1980 pathname = linker_search_module(modname, 1981 strlen(modname), verinfo); 1982 } 1983 if (pathname == NULL) 1984 return (ENOENT); 1985 1986 /* 1987 * Can't load more than one file with the same basename XXX: 1988 * Actually it should be possible to have multiple KLDs with 1989 * the same basename but different path because they can 1990 * provide different versions of the same modules. 1991 */ 1992 filename = linker_basename(pathname); 1993 if (linker_find_file_by_name(filename)) 1994 error = EEXIST; 1995 else do { 1996 error = linker_load_file(pathname, &lfdep); 1997 if (error) 1998 break; 1999 if (modname && verinfo && 2000 modlist_lookup2(modname, verinfo) == NULL) { 2001 linker_file_unload(lfdep, LINKER_UNLOAD_FORCE); 2002 error = ENOENT; 2003 break; 2004 } 2005 if (parent) { 2006 error = linker_file_add_dependency(parent, lfdep); 2007 if (error) 2008 break; 2009 } 2010 if (lfpp) 2011 *lfpp = lfdep; 2012 } while (0); 2013 free(pathname, M_LINKER); 2014 return (error); 2015 } 2016 2017 /* 2018 * This routine is responsible for finding dependencies of userland initiated 2019 * kldload(2)'s of files. 2020 */ 2021 int 2022 linker_load_dependencies(linker_file_t lf) 2023 { 2024 linker_file_t lfdep; 2025 struct mod_metadata **start, **stop, **mdp, **nmdp; 2026 struct mod_metadata *mp, *nmp; 2027 struct mod_depend *verinfo; 2028 modlist_t mod; 2029 const char *modname, *nmodname; 2030 int ver, error = 0, count; 2031 2032 /* 2033 * All files are dependant on /kernel. 2034 */ 2035 KLD_LOCK_ASSERT(); 2036 if (linker_kernel_file) { 2037 linker_kernel_file->refs++; 2038 error = linker_file_add_dependency(lf, linker_kernel_file); 2039 if (error) 2040 return (error); 2041 } 2042 if (linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop, 2043 &count) != 0) 2044 return (0); 2045 for (mdp = start; mdp < stop; mdp++) { 2046 mp = *mdp; 2047 if (mp->md_type != MDT_VERSION) 2048 continue; 2049 modname = mp->md_cval; 2050 ver = ((struct mod_version *)mp->md_data)->mv_version; 2051 mod = modlist_lookup(modname, ver); 2052 if (mod != NULL) { 2053 printf("interface %s.%d already present in the KLD" 2054 " '%s'!\n", modname, ver, 2055 mod->container->filename); 2056 return (EEXIST); 2057 } 2058 } 2059 2060 for (mdp = start; mdp < stop; mdp++) { 2061 mp = *mdp; 2062 if (mp->md_type != MDT_DEPEND) 2063 continue; 2064 modname = mp->md_cval; 2065 verinfo = mp->md_data; 2066 nmodname = NULL; 2067 for (nmdp = start; nmdp < stop; nmdp++) { 2068 nmp = *nmdp; 2069 if (nmp->md_type != MDT_VERSION) 2070 continue; 2071 nmodname = nmp->md_cval; 2072 if (strcmp(modname, nmodname) == 0) 2073 break; 2074 } 2075 if (nmdp < stop)/* early exit, it's a self reference */ 2076 continue; 2077 mod = modlist_lookup2(modname, verinfo); 2078 if (mod) { /* woohoo, it's loaded already */ 2079 lfdep = mod->container; 2080 lfdep->refs++; 2081 error = linker_file_add_dependency(lf, lfdep); 2082 if (error) 2083 break; 2084 continue; 2085 } 2086 error = linker_load_module(NULL, modname, lf, verinfo, NULL); 2087 if (error) { 2088 printf("KLD %s: depends on %s - not available or" 2089 " version mismatch\n", lf->filename, modname); 2090 break; 2091 } 2092 } 2093 2094 if (error) 2095 return (error); 2096 linker_addmodules(lf, start, stop, 0); 2097 return (error); 2098 } 2099 2100 static int 2101 sysctl_kern_function_list_iterate(const char *name, void *opaque) 2102 { 2103 struct sysctl_req *req; 2104 2105 req = opaque; 2106 return (SYSCTL_OUT(req, name, strlen(name) + 1)); 2107 } 2108 2109 /* 2110 * Export a nul-separated, double-nul-terminated list of all function names 2111 * in the kernel. 2112 */ 2113 static int 2114 sysctl_kern_function_list(SYSCTL_HANDLER_ARGS) 2115 { 2116 linker_file_t lf; 2117 int error; 2118 2119 #ifdef MAC 2120 error = mac_kld_check_stat(req->td->td_ucred); 2121 if (error) 2122 return (error); 2123 #endif 2124 error = sysctl_wire_old_buffer(req, 0); 2125 if (error != 0) 2126 return (error); 2127 KLD_LOCK(); 2128 TAILQ_FOREACH(lf, &linker_files, link) { 2129 error = LINKER_EACH_FUNCTION_NAME(lf, 2130 sysctl_kern_function_list_iterate, req); 2131 if (error) { 2132 KLD_UNLOCK(); 2133 return (error); 2134 } 2135 } 2136 KLD_UNLOCK(); 2137 return (SYSCTL_OUT(req, "", 1)); 2138 } 2139 2140 SYSCTL_PROC(_kern, OID_AUTO, function_list, CTLFLAG_RD, 2141 NULL, 0, sysctl_kern_function_list, "", "kernel function list"); 2142