kern_linker.c revision 159588
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: head/sys/kern/kern_linker.c 159588 2006-06-13 21:28:18Z jhb $"); 29 30#include "opt_ddb.h" 31#include "opt_hwpmc_hooks.h" 32#include "opt_mac.h" 33 34#include <sys/param.h> 35#include <sys/kernel.h> 36#include <sys/systm.h> 37#include <sys/malloc.h> 38#include <sys/sysproto.h> 39#include <sys/sysent.h> 40#include <sys/proc.h> 41#include <sys/lock.h> 42#include <sys/mutex.h> 43#include <sys/sx.h> 44#include <sys/mac.h> 45#include <sys/module.h> 46#include <sys/linker.h> 47#include <sys/fcntl.h> 48#include <sys/libkern.h> 49#include <sys/namei.h> 50#include <sys/vnode.h> 51#include <sys/syscallsubr.h> 52#include <sys/sysctl.h> 53 54#include "linker_if.h" 55 56#ifdef HWPMC_HOOKS 57#include <sys/pmckern.h> 58#endif 59 60#ifdef KLD_DEBUG 61int kld_debug = 0; 62#endif 63 64/* 65 * static char *linker_search_path(const char *name, struct mod_depend 66 * *verinfo); 67 */ 68static const char *linker_basename(const char *path); 69 70/* Metadata from the static kernel */ 71SET_DECLARE(modmetadata_set, struct mod_metadata); 72 73MALLOC_DEFINE(M_LINKER, "linker", "kernel linker"); 74 75linker_file_t linker_kernel_file; 76 77static struct mtx kld_mtx; /* kernel linker mutex */ 78 79static linker_class_list_t classes; 80static linker_file_list_t linker_files; 81static int next_file_id = 1; 82static int linker_no_more_classes = 0; 83 84#define LINKER_GET_NEXT_FILE_ID(a) do { \ 85 linker_file_t lftmp; \ 86 \ 87retry: \ 88 mtx_lock(&kld_mtx); \ 89 TAILQ_FOREACH(lftmp, &linker_files, link) { \ 90 if (next_file_id == lftmp->id) { \ 91 next_file_id++; \ 92 mtx_unlock(&kld_mtx); \ 93 goto retry; \ 94 } \ 95 } \ 96 (a) = next_file_id; \ 97 mtx_unlock(&kld_mtx); /* Hold for safe read of id variable */ \ 98} while(0) 99 100 101/* XXX wrong name; we're looking at version provision tags here, not modules */ 102typedef TAILQ_HEAD(, modlist) modlisthead_t; 103struct modlist { 104 TAILQ_ENTRY(modlist) link; /* chain together all modules */ 105 linker_file_t container; 106 const char *name; 107 int version; 108}; 109typedef struct modlist *modlist_t; 110static modlisthead_t found_modules; 111 112static modlist_t modlist_lookup2(const char *name, 113 struct mod_depend *verinfo); 114 115static char * 116linker_strdup(const char *str) 117{ 118 char *result; 119 120 if ((result = malloc((strlen(str) + 1), M_LINKER, M_WAITOK)) != NULL) 121 strcpy(result, str); 122 return (result); 123} 124 125static void 126linker_init(void *arg) 127{ 128 129 mtx_init(&kld_mtx, "kernel linker", NULL, MTX_DEF); 130 TAILQ_INIT(&classes); 131 TAILQ_INIT(&linker_files); 132} 133 134SYSINIT(linker, SI_SUB_KLD, SI_ORDER_FIRST, linker_init, 0) 135 136static void 137linker_stop_class_add(void *arg) 138{ 139 140 linker_no_more_classes = 1; 141} 142 143SYSINIT(linker_class, SI_SUB_KLD, SI_ORDER_ANY, linker_stop_class_add, NULL) 144 145int 146linker_add_class(linker_class_t lc) 147{ 148 149 /* 150 * We disallow any class registration past SI_ORDER_ANY 151 * of SI_SUB_KLD. We bump the reference count to keep the 152 * ops from being freed. 153 */ 154 if (linker_no_more_classes == 1) 155 return (EPERM); 156 kobj_class_compile((kobj_class_t) lc); 157 ((kobj_class_t)lc)->refs++; /* XXX: kobj_mtx */ 158 TAILQ_INSERT_TAIL(&classes, lc, link); 159 return (0); 160} 161 162static void 163linker_file_sysinit(linker_file_t lf) 164{ 165 struct sysinit **start, **stop, **sipp, **xipp, *save; 166 167 KLD_DPF(FILE, ("linker_file_sysinit: calling SYSINITs for %s\n", 168 lf->filename)); 169 170 if (linker_file_lookup_set(lf, "sysinit_set", &start, &stop, NULL) != 0) 171 return; 172 /* 173 * Perform a bubble sort of the system initialization objects by 174 * their subsystem (primary key) and order (secondary key). 175 * 176 * Since some things care about execution order, this is the operation 177 * which ensures continued function. 178 */ 179 for (sipp = start; sipp < stop; sipp++) { 180 for (xipp = sipp + 1; xipp < stop; xipp++) { 181 if ((*sipp)->subsystem < (*xipp)->subsystem || 182 ((*sipp)->subsystem == (*xipp)->subsystem && 183 (*sipp)->order <= (*xipp)->order)) 184 continue; /* skip */ 185 save = *sipp; 186 *sipp = *xipp; 187 *xipp = save; 188 } 189 } 190 191 /* 192 * Traverse the (now) ordered list of system initialization tasks. 193 * Perform each task, and continue on to the next task. 194 */ 195 for (sipp = start; sipp < stop; sipp++) { 196 if ((*sipp)->subsystem == SI_SUB_DUMMY) 197 continue; /* skip dummy task(s) */ 198 199 /* Call function */ 200 (*((*sipp)->func)) ((*sipp)->udata); 201 } 202} 203 204static void 205linker_file_sysuninit(linker_file_t lf) 206{ 207 struct sysinit **start, **stop, **sipp, **xipp, *save; 208 209 KLD_DPF(FILE, ("linker_file_sysuninit: calling SYSUNINITs for %s\n", 210 lf->filename)); 211 212 if (linker_file_lookup_set(lf, "sysuninit_set", &start, &stop, 213 NULL) != 0) 214 return; 215 216 /* 217 * Perform a reverse bubble sort of the system initialization objects 218 * by their subsystem (primary key) and order (secondary key). 219 * 220 * Since some things care about execution order, this is the operation 221 * which ensures continued function. 222 */ 223 for (sipp = start; sipp < stop; sipp++) { 224 for (xipp = sipp + 1; xipp < stop; xipp++) { 225 if ((*sipp)->subsystem > (*xipp)->subsystem || 226 ((*sipp)->subsystem == (*xipp)->subsystem && 227 (*sipp)->order >= (*xipp)->order)) 228 continue; /* skip */ 229 save = *sipp; 230 *sipp = *xipp; 231 *xipp = save; 232 } 233 } 234 235 /* 236 * Traverse the (now) ordered list of system initialization tasks. 237 * Perform each task, and continue on to the next task. 238 */ 239 for (sipp = start; sipp < stop; sipp++) { 240 if ((*sipp)->subsystem == SI_SUB_DUMMY) 241 continue; /* skip dummy task(s) */ 242 243 /* Call function */ 244 (*((*sipp)->func)) ((*sipp)->udata); 245 } 246} 247 248static void 249linker_file_register_sysctls(linker_file_t lf) 250{ 251 struct sysctl_oid **start, **stop, **oidp; 252 253 KLD_DPF(FILE, 254 ("linker_file_register_sysctls: registering SYSCTLs for %s\n", 255 lf->filename)); 256 257 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0) 258 return; 259 260 for (oidp = start; oidp < stop; oidp++) 261 sysctl_register_oid(*oidp); 262} 263 264static void 265linker_file_unregister_sysctls(linker_file_t lf) 266{ 267 struct sysctl_oid **start, **stop, **oidp; 268 269 KLD_DPF(FILE, ("linker_file_unregister_sysctls: registering SYSCTLs" 270 " for %s\n", lf->filename)); 271 272 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0) 273 return; 274 275 for (oidp = start; oidp < stop; oidp++) 276 sysctl_unregister_oid(*oidp); 277} 278 279static int 280linker_file_register_modules(linker_file_t lf) 281{ 282 struct mod_metadata **start, **stop, **mdp; 283 const moduledata_t *moddata; 284 int first_error, error; 285 286 KLD_DPF(FILE, ("linker_file_register_modules: registering modules" 287 " in %s\n", lf->filename)); 288 289 if (linker_file_lookup_set(lf, "modmetadata_set", &start, 290 &stop, 0) != 0) { 291 /* 292 * This fallback should be unnecessary, but if we get booted 293 * from boot2 instead of loader and we are missing our 294 * metadata then we have to try the best we can. 295 */ 296 if (lf == linker_kernel_file) { 297 start = SET_BEGIN(modmetadata_set); 298 stop = SET_LIMIT(modmetadata_set); 299 } else 300 return (0); 301 } 302 first_error = 0; 303 for (mdp = start; mdp < stop; mdp++) { 304 if ((*mdp)->md_type != MDT_MODULE) 305 continue; 306 moddata = (*mdp)->md_data; 307 KLD_DPF(FILE, ("Registering module %s in %s\n", 308 moddata->name, lf->filename)); 309 error = module_register(moddata, lf); 310 if (error) { 311 printf("Module %s failed to register: %d\n", 312 moddata->name, error); 313 if (first_error == 0) 314 first_error = error; 315 } 316 } 317 return (first_error); 318} 319 320static void 321linker_init_kernel_modules(void) 322{ 323 324 linker_file_register_modules(linker_kernel_file); 325} 326 327SYSINIT(linker_kernel, SI_SUB_KLD, SI_ORDER_ANY, linker_init_kernel_modules, 0) 328 329static int 330linker_load_file(const char *filename, linker_file_t *result) 331{ 332 linker_class_t lc; 333 linker_file_t lf; 334 int foundfile, error; 335 336 /* Refuse to load modules if securelevel raised */ 337 if (securelevel > 0) 338 return (EPERM); 339 340 lf = linker_find_file_by_name(filename); 341 if (lf) { 342 KLD_DPF(FILE, ("linker_load_file: file %s is already loaded," 343 " incrementing refs\n", filename)); 344 *result = lf; 345 lf->refs++; 346 return (0); 347 } 348 lf = NULL; 349 foundfile = 0; 350 error = 0; 351 352 /* 353 * We do not need to protect (lock) classes here because there is 354 * no class registration past startup (SI_SUB_KLD, SI_ORDER_ANY) 355 * and there is no class deregistration mechanism at this time. 356 */ 357 TAILQ_FOREACH(lc, &classes, link) { 358 KLD_DPF(FILE, ("linker_load_file: trying to load %s\n", 359 filename)); 360 error = LINKER_LOAD_FILE(lc, filename, &lf); 361 /* 362 * If we got something other than ENOENT, then it exists but 363 * we cannot load it for some other reason. 364 */ 365 if (error != ENOENT) 366 foundfile = 1; 367 if (lf) { 368 error = linker_file_register_modules(lf); 369 if (error == EEXIST) { 370 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 371 return (error); 372 } 373 linker_file_register_sysctls(lf); 374 linker_file_sysinit(lf); 375 lf->flags |= LINKER_FILE_LINKED; 376 *result = lf; 377 return (0); 378 } 379 } 380 /* 381 * Less than ideal, but tells the user whether it failed to load or 382 * the module was not found. 383 */ 384 if (foundfile) { 385 /* 386 * Format not recognized or otherwise unloadable. 387 * When loading a module that is statically built into 388 * the kernel EEXIST percolates back up as the return 389 * value. Preserve this so that apps like sysinstall 390 * can recognize this special case and not post bogus 391 * dialog boxes. 392 */ 393 if (error != EEXIST) 394 error = ENOEXEC; 395 } else 396 error = ENOENT; /* Nothing found */ 397 return (error); 398} 399 400int 401linker_reference_module(const char *modname, struct mod_depend *verinfo, 402 linker_file_t *result) 403{ 404 modlist_t mod; 405 406 if ((mod = modlist_lookup2(modname, verinfo)) != NULL) { 407 *result = mod->container; 408 (*result)->refs++; 409 return (0); 410 } 411 412 return (linker_load_module(NULL, modname, NULL, verinfo, result)); 413} 414 415linker_file_t 416linker_find_file_by_name(const char *filename) 417{ 418 linker_file_t lf; 419 char *koname; 420 421 koname = malloc(strlen(filename) + 4, M_LINKER, M_WAITOK); 422 sprintf(koname, "%s.ko", filename); 423 424 mtx_lock(&kld_mtx); 425 TAILQ_FOREACH(lf, &linker_files, link) { 426 if (strcmp(lf->filename, koname) == 0) 427 break; 428 if (strcmp(lf->filename, filename) == 0) 429 break; 430 } 431 mtx_unlock(&kld_mtx); 432 free(koname, M_LINKER); 433 return (lf); 434} 435 436linker_file_t 437linker_find_file_by_id(int fileid) 438{ 439 linker_file_t lf; 440 441 mtx_lock(&kld_mtx); 442 TAILQ_FOREACH(lf, &linker_files, link) 443 if (lf->id == fileid) 444 break; 445 mtx_unlock(&kld_mtx); 446 return (lf); 447} 448 449linker_file_t 450linker_make_file(const char *pathname, linker_class_t lc) 451{ 452 linker_file_t lf; 453 const char *filename; 454 455 filename = linker_basename(pathname); 456 457 KLD_DPF(FILE, ("linker_make_file: new file, filename=%s\n", filename)); 458 lf = (linker_file_t)kobj_create((kobj_class_t)lc, M_LINKER, M_WAITOK); 459 if (lf == NULL) 460 return (NULL); 461 lf->refs = 1; 462 lf->userrefs = 0; 463 lf->flags = 0; 464 lf->filename = linker_strdup(filename); 465 LINKER_GET_NEXT_FILE_ID(lf->id); 466 lf->ndeps = 0; 467 lf->deps = NULL; 468 STAILQ_INIT(&lf->common); 469 TAILQ_INIT(&lf->modules); 470 mtx_lock(&kld_mtx); 471 TAILQ_INSERT_TAIL(&linker_files, lf, link); 472 mtx_unlock(&kld_mtx); 473 return (lf); 474} 475 476int 477linker_file_unload(linker_file_t file, int flags) 478{ 479 module_t mod, next; 480 modlist_t ml, nextml; 481 struct common_symbol *cp; 482 int error, i; 483 484 /* Refuse to unload modules if securelevel raised. */ 485 if (securelevel > 0) 486 return (EPERM); 487#ifdef MAC 488 error = mac_check_kld_unload(curthread->td_ucred); 489 if (error) 490 return (error); 491#endif 492 493 KLD_DPF(FILE, ("linker_file_unload: lf->refs=%d\n", file->refs)); 494 495 /* Easy case of just dropping a reference. */ 496 if (file->refs > 1) { 497 file->refs--; 498 return (0); 499 } 500 501 KLD_DPF(FILE, ("linker_file_unload: file is unloading," 502 " informing modules\n")); 503 504 /* 505 * Inform any modules associated with this file. 506 */ 507 MOD_XLOCK; 508 for (mod = TAILQ_FIRST(&file->modules); mod; mod = next) { 509 next = module_getfnext(mod); 510 MOD_XUNLOCK; 511 512 /* 513 * Give the module a chance to veto the unload. 514 */ 515 if ((error = module_unload(mod, flags)) != 0) { 516 KLD_DPF(FILE, ("linker_file_unload: module %p" 517 " vetoes unload\n", mod)); 518 return (error); 519 } 520 MOD_XLOCK; 521 module_release(mod); 522 } 523 MOD_XUNLOCK; 524 525 TAILQ_FOREACH_SAFE(ml, &found_modules, link, nextml) { 526 if (ml->container == file) { 527 TAILQ_REMOVE(&found_modules, ml, link); 528 free(ml, M_LINKER); 529 } 530 } 531 532 /* 533 * Don't try to run SYSUNINITs if we are unloaded due to a 534 * link error. 535 */ 536 if (file->flags & LINKER_FILE_LINKED) { 537 linker_file_sysuninit(file); 538 linker_file_unregister_sysctls(file); 539 } 540 mtx_lock(&kld_mtx); 541 TAILQ_REMOVE(&linker_files, file, link); 542 mtx_unlock(&kld_mtx); 543 544 if (file->deps) { 545 for (i = 0; i < file->ndeps; i++) 546 linker_file_unload(file->deps[i], flags); 547 free(file->deps, M_LINKER); 548 file->deps = NULL; 549 } 550 for (cp = STAILQ_FIRST(&file->common); cp; 551 cp = STAILQ_FIRST(&file->common)) { 552 STAILQ_REMOVE(&file->common, cp, common_symbol, link); 553 free(cp, M_LINKER); 554 } 555 556 LINKER_UNLOAD(file); 557 if (file->filename) { 558 free(file->filename, M_LINKER); 559 file->filename = NULL; 560 } 561 kobj_delete((kobj_t) file, M_LINKER); 562 return (0); 563} 564 565int 566linker_file_add_dependency(linker_file_t file, linker_file_t dep) 567{ 568 linker_file_t *newdeps; 569 570 newdeps = malloc((file->ndeps + 1) * sizeof(linker_file_t *), 571 M_LINKER, M_WAITOK | M_ZERO); 572 if (newdeps == NULL) 573 return (ENOMEM); 574 575 if (file->deps) { 576 bcopy(file->deps, newdeps, 577 file->ndeps * sizeof(linker_file_t *)); 578 free(file->deps, M_LINKER); 579 } 580 file->deps = newdeps; 581 file->deps[file->ndeps] = dep; 582 file->ndeps++; 583 return (0); 584} 585 586/* 587 * Locate a linker set and its contents. This is a helper function to avoid 588 * linker_if.h exposure elsewhere. Note: firstp and lastp are really void *** 589 */ 590int 591linker_file_lookup_set(linker_file_t file, const char *name, 592 void *firstp, void *lastp, int *countp) 593{ 594 595 return (LINKER_LOOKUP_SET(file, name, firstp, lastp, countp)); 596} 597 598caddr_t 599linker_file_lookup_symbol(linker_file_t file, const char *name, int deps) 600{ 601 c_linker_sym_t sym; 602 linker_symval_t symval; 603 caddr_t address; 604 size_t common_size = 0; 605 int i; 606 607 KLD_DPF(SYM, ("linker_file_lookup_symbol: file=%p, name=%s, deps=%d\n", 608 file, name, deps)); 609 610 if (LINKER_LOOKUP_SYMBOL(file, name, &sym) == 0) { 611 LINKER_SYMBOL_VALUES(file, sym, &symval); 612 if (symval.value == 0) 613 /* 614 * For commons, first look them up in the 615 * dependencies and only allocate space if not found 616 * there. 617 */ 618 common_size = symval.size; 619 else { 620 KLD_DPF(SYM, ("linker_file_lookup_symbol: symbol" 621 ".value=%p\n", symval.value)); 622 return (symval.value); 623 } 624 } 625 if (deps) { 626 for (i = 0; i < file->ndeps; i++) { 627 address = linker_file_lookup_symbol(file->deps[i], 628 name, 0); 629 if (address) { 630 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 631 " deps value=%p\n", address)); 632 return (address); 633 } 634 } 635 } 636 if (common_size > 0) { 637 /* 638 * This is a common symbol which was not found in the 639 * dependencies. We maintain a simple common symbol table in 640 * the file object. 641 */ 642 struct common_symbol *cp; 643 644 STAILQ_FOREACH(cp, &file->common, link) { 645 if (strcmp(cp->name, name) == 0) { 646 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 647 " old common value=%p\n", cp->address)); 648 return (cp->address); 649 } 650 } 651 /* 652 * Round the symbol size up to align. 653 */ 654 common_size = (common_size + sizeof(int) - 1) & -sizeof(int); 655 cp = malloc(sizeof(struct common_symbol) 656 + common_size + strlen(name) + 1, M_LINKER, 657 M_WAITOK | M_ZERO); 658 if (cp == NULL) { 659 KLD_DPF(SYM, ("linker_file_lookup_symbol: nomem\n")); 660 return (0); 661 } 662 cp->address = (caddr_t)(cp + 1); 663 cp->name = cp->address + common_size; 664 strcpy(cp->name, name); 665 bzero(cp->address, common_size); 666 STAILQ_INSERT_TAIL(&file->common, cp, link); 667 668 KLD_DPF(SYM, ("linker_file_lookup_symbol: new common" 669 " value=%p\n", cp->address)); 670 return (cp->address); 671 } 672 KLD_DPF(SYM, ("linker_file_lookup_symbol: fail\n")); 673 return (0); 674} 675 676#ifdef DDB 677/* 678 * DDB Helpers. DDB has to look across multiple files with their own symbol 679 * tables and string tables. 680 * 681 * Note that we do not obey list locking protocols here. We really don't need 682 * DDB to hang because somebody's got the lock held. We'll take the chance 683 * that the files list is inconsistant instead. 684 */ 685 686int 687linker_ddb_lookup(const char *symstr, c_linker_sym_t *sym) 688{ 689 linker_file_t lf; 690 691 TAILQ_FOREACH(lf, &linker_files, link) { 692 if (LINKER_LOOKUP_SYMBOL(lf, symstr, sym) == 0) 693 return (0); 694 } 695 return (ENOENT); 696} 697 698int 699linker_ddb_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) 700{ 701 linker_file_t lf; 702 c_linker_sym_t best, es; 703 u_long diff, bestdiff, off; 704 705 best = 0; 706 off = (uintptr_t)value; 707 bestdiff = off; 708 TAILQ_FOREACH(lf, &linker_files, link) { 709 if (LINKER_SEARCH_SYMBOL(lf, value, &es, &diff) != 0) 710 continue; 711 if (es != 0 && diff < bestdiff) { 712 best = es; 713 bestdiff = diff; 714 } 715 if (bestdiff == 0) 716 break; 717 } 718 if (best) { 719 *sym = best; 720 *diffp = bestdiff; 721 return (0); 722 } else { 723 *sym = 0; 724 *diffp = off; 725 return (ENOENT); 726 } 727} 728 729int 730linker_ddb_symbol_values(c_linker_sym_t sym, linker_symval_t *symval) 731{ 732 linker_file_t lf; 733 734 TAILQ_FOREACH(lf, &linker_files, link) { 735 if (LINKER_SYMBOL_VALUES(lf, sym, symval) == 0) 736 return (0); 737 } 738 return (ENOENT); 739} 740#endif 741 742/* 743 * Syscalls. 744 */ 745/* 746 * MPSAFE 747 */ 748int 749kern_kldload(struct thread *td, const char *file, int *fileid) 750{ 751#ifdef HWPMC_HOOKS 752 struct pmckern_map_in pkm; 753#endif 754 const char *kldname, *modname; 755 linker_file_t lf; 756 int error; 757 758 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 759 return (error); 760 761 if ((error = suser(td)) != 0) 762 return (error); 763 764 /* 765 * If file does not contain qualified name or any dot in it 766 * (kldname.ko, or kldname.ver.ko) treat it as interface 767 * name. 768 */ 769 if (index(file, '/') || index(file, '.')) { 770 kldname = file; 771 modname = NULL; 772 } else { 773 kldname = NULL; 774 modname = file; 775 } 776 777 mtx_lock(&Giant); 778 error = linker_load_module(kldname, modname, NULL, NULL, &lf); 779 if (error) 780 goto unlock; 781 782#ifdef HWPMC_HOOKS 783 pkm.pm_file = lf->filename; 784 pkm.pm_address = (uintptr_t) lf->address; 785 PMC_CALL_HOOK(td, PMC_FN_KLD_LOAD, (void *) &pkm); 786#endif 787 lf->userrefs++; 788 if (fileid != NULL) 789 *fileid = lf->id; 790unlock: 791 mtx_unlock(&Giant); 792 return (error); 793} 794 795int 796kldload(struct thread *td, struct kldload_args *uap) 797{ 798 char *pathname = NULL; 799 int error; 800 801 td->td_retval[0] = -1; 802 803 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 804 error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL); 805 if (error == 0) 806 error = kern_kldload(td, pathname, &td->td_retval[0]); 807 808 free(pathname, M_TEMP); 809 return (error); 810} 811 812/* 813 * MPSAFE 814 */ 815int 816kern_kldunload(struct thread *td, int fileid, int flags) 817{ 818#ifdef HWPMC_HOOKS 819 struct pmckern_map_out pkm; 820#endif 821 linker_file_t lf; 822 int error = 0; 823 824 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 825 return (error); 826 827 if ((error = suser(td)) != 0) 828 return (error); 829 830 mtx_lock(&Giant); 831 lf = linker_find_file_by_id(fileid); 832 if (lf) { 833 KLD_DPF(FILE, ("kldunload: lf->userrefs=%d\n", lf->userrefs)); 834 if (lf->userrefs == 0) { 835 /* 836 * XXX: maybe LINKER_UNLOAD_FORCE should override ? 837 */ 838 printf("kldunload: attempt to unload file that was" 839 " loaded by the kernel\n"); 840 error = EBUSY; 841 } else { 842#ifdef HWPMC_HOOKS 843 /* Save data needed by hwpmc(4) before unloading. */ 844 pkm.pm_address = (uintptr_t) lf->address; 845 pkm.pm_size = lf->size; 846#endif 847 lf->userrefs--; 848 error = linker_file_unload(lf, flags); 849 if (error) 850 lf->userrefs++; 851 } 852 } else 853 error = ENOENT; 854 855#ifdef HWPMC_HOOKS 856 if (error == 0) 857 PMC_CALL_HOOK(td, PMC_FN_KLD_UNLOAD, (void *) &pkm); 858#endif 859 mtx_unlock(&Giant); 860 return (error); 861} 862 863/* 864 * MPSAFE 865 */ 866int 867kldunload(struct thread *td, struct kldunload_args *uap) 868{ 869 870 return (kern_kldunload(td, uap->fileid, LINKER_UNLOAD_NORMAL)); 871} 872 873/* 874 * MPSAFE 875 */ 876int 877kldunloadf(struct thread *td, struct kldunloadf_args *uap) 878{ 879 880 if (uap->flags != LINKER_UNLOAD_NORMAL && 881 uap->flags != LINKER_UNLOAD_FORCE) 882 return (EINVAL); 883 return (kern_kldunload(td, uap->fileid, uap->flags)); 884} 885 886/* 887 * MPSAFE 888 */ 889int 890kldfind(struct thread *td, struct kldfind_args *uap) 891{ 892 char *pathname; 893 const char *filename; 894 linker_file_t lf; 895 int error = 0; 896 897#ifdef MAC 898 error = mac_check_kld_stat(td->td_ucred); 899 if (error) 900 return (error); 901#endif 902 903 mtx_lock(&Giant); 904 td->td_retval[0] = -1; 905 906 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 907 if ((error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL)) != 0) 908 goto out; 909 910 filename = linker_basename(pathname); 911 lf = linker_find_file_by_name(filename); 912 if (lf) 913 td->td_retval[0] = lf->id; 914 else 915 error = ENOENT; 916out: 917 if (pathname) 918 free(pathname, M_TEMP); 919 mtx_unlock(&Giant); 920 return (error); 921} 922 923/* 924 * MPSAFE 925 */ 926int 927kldnext(struct thread *td, struct kldnext_args *uap) 928{ 929 linker_file_t lf; 930 int error = 0; 931 932#ifdef MAC 933 error = mac_check_kld_stat(td->td_ucred); 934 if (error) 935 return (error); 936#endif 937 938 mtx_lock(&Giant); 939 940 if (uap->fileid == 0) { 941 mtx_lock(&kld_mtx); 942 if (TAILQ_FIRST(&linker_files)) 943 td->td_retval[0] = TAILQ_FIRST(&linker_files)->id; 944 else 945 td->td_retval[0] = 0; 946 mtx_unlock(&kld_mtx); 947 goto out; 948 } 949 lf = linker_find_file_by_id(uap->fileid); 950 if (lf) { 951 if (TAILQ_NEXT(lf, link)) 952 td->td_retval[0] = TAILQ_NEXT(lf, link)->id; 953 else 954 td->td_retval[0] = 0; 955 } else 956 error = ENOENT; 957out: 958 mtx_unlock(&Giant); 959 return (error); 960} 961 962/* 963 * MPSAFE 964 */ 965int 966kldstat(struct thread *td, struct kldstat_args *uap) 967{ 968 struct kld_file_stat stat; 969 linker_file_t lf; 970 int error, namelen; 971 972 /* 973 * Check the version of the user's structure. 974 */ 975 error = copyin(uap->stat, &stat, sizeof(struct kld_file_stat)); 976 if (error) 977 return (error); 978 if (stat.version != sizeof(struct kld_file_stat)) 979 return (EINVAL); 980 981#ifdef MAC 982 error = mac_check_kld_stat(td->td_ucred); 983 if (error) 984 return (error); 985#endif 986 987 mtx_lock(&Giant); 988 989 lf = linker_find_file_by_id(uap->fileid); 990 if (lf == NULL) { 991 mtx_unlock(&Giant); 992 return (ENOENT); 993 } 994 995 namelen = strlen(lf->filename) + 1; 996 if (namelen > MAXPATHLEN) 997 namelen = MAXPATHLEN; 998 bcopy(lf->filename, &stat.name[0], namelen); 999 stat.refs = lf->refs; 1000 stat.id = lf->id; 1001 stat.address = lf->address; 1002 stat.size = lf->size; 1003 mtx_unlock(&Giant); 1004 1005 td->td_retval[0] = 0; 1006 1007 return (copyout(&stat, uap->stat, sizeof(struct kld_file_stat))); 1008} 1009 1010/* 1011 * MPSAFE 1012 */ 1013int 1014kldfirstmod(struct thread *td, struct kldfirstmod_args *uap) 1015{ 1016 linker_file_t lf; 1017 module_t mp; 1018 int error = 0; 1019 1020#ifdef MAC 1021 error = mac_check_kld_stat(td->td_ucred); 1022 if (error) 1023 return (error); 1024#endif 1025 1026 mtx_lock(&Giant); 1027 lf = linker_find_file_by_id(uap->fileid); 1028 if (lf) { 1029 MOD_SLOCK; 1030 mp = TAILQ_FIRST(&lf->modules); 1031 if (mp != NULL) 1032 td->td_retval[0] = module_getid(mp); 1033 else 1034 td->td_retval[0] = 0; 1035 MOD_SUNLOCK; 1036 } else 1037 error = ENOENT; 1038 mtx_unlock(&Giant); 1039 return (error); 1040} 1041 1042/* 1043 * MPSAFE 1044 */ 1045int 1046kldsym(struct thread *td, struct kldsym_args *uap) 1047{ 1048 char *symstr = NULL; 1049 c_linker_sym_t sym; 1050 linker_symval_t symval; 1051 linker_file_t lf; 1052 struct kld_sym_lookup lookup; 1053 int error = 0; 1054 1055#ifdef MAC 1056 error = mac_check_kld_stat(td->td_ucred); 1057 if (error) 1058 return (error); 1059#endif 1060 1061 mtx_lock(&Giant); 1062 1063 if ((error = copyin(uap->data, &lookup, sizeof(lookup))) != 0) 1064 goto out; 1065 if (lookup.version != sizeof(lookup) || 1066 uap->cmd != KLDSYM_LOOKUP) { 1067 error = EINVAL; 1068 goto out; 1069 } 1070 symstr = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1071 if ((error = copyinstr(lookup.symname, symstr, MAXPATHLEN, NULL)) != 0) 1072 goto out; 1073 if (uap->fileid != 0) { 1074 lf = linker_find_file_by_id(uap->fileid); 1075 if (lf == NULL) { 1076 error = ENOENT; 1077 goto out; 1078 } 1079 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 1080 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 1081 lookup.symvalue = (uintptr_t) symval.value; 1082 lookup.symsize = symval.size; 1083 error = copyout(&lookup, uap->data, sizeof(lookup)); 1084 } else 1085 error = ENOENT; 1086 } else { 1087 mtx_lock(&kld_mtx); 1088 TAILQ_FOREACH(lf, &linker_files, link) { 1089 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 1090 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 1091 lookup.symvalue = (uintptr_t)symval.value; 1092 lookup.symsize = symval.size; 1093 error = copyout(&lookup, uap->data, 1094 sizeof(lookup)); 1095 break; 1096 } 1097 } 1098 mtx_unlock(&kld_mtx); 1099 if (lf == NULL) 1100 error = ENOENT; 1101 } 1102out: 1103 if (symstr) 1104 free(symstr, M_TEMP); 1105 mtx_unlock(&Giant); 1106 return (error); 1107} 1108 1109/* 1110 * Preloaded module support 1111 */ 1112 1113static modlist_t 1114modlist_lookup(const char *name, int ver) 1115{ 1116 modlist_t mod; 1117 1118 TAILQ_FOREACH(mod, &found_modules, link) { 1119 if (strcmp(mod->name, name) == 0 && 1120 (ver == 0 || mod->version == ver)) 1121 return (mod); 1122 } 1123 return (NULL); 1124} 1125 1126static modlist_t 1127modlist_lookup2(const char *name, struct mod_depend *verinfo) 1128{ 1129 modlist_t mod, bestmod; 1130 int ver; 1131 1132 if (verinfo == NULL) 1133 return (modlist_lookup(name, 0)); 1134 bestmod = NULL; 1135 TAILQ_FOREACH(mod, &found_modules, link) { 1136 if (strcmp(mod->name, name) != 0) 1137 continue; 1138 ver = mod->version; 1139 if (ver == verinfo->md_ver_preferred) 1140 return (mod); 1141 if (ver >= verinfo->md_ver_minimum && 1142 ver <= verinfo->md_ver_maximum && 1143 (bestmod == NULL || ver > bestmod->version)) 1144 bestmod = mod; 1145 } 1146 return (bestmod); 1147} 1148 1149static modlist_t 1150modlist_newmodule(const char *modname, int version, linker_file_t container) 1151{ 1152 modlist_t mod; 1153 1154 mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT | M_ZERO); 1155 if (mod == NULL) 1156 panic("no memory for module list"); 1157 mod->container = container; 1158 mod->name = modname; 1159 mod->version = version; 1160 TAILQ_INSERT_TAIL(&found_modules, mod, link); 1161 return (mod); 1162} 1163 1164static void 1165linker_addmodules(linker_file_t lf, struct mod_metadata **start, 1166 struct mod_metadata **stop, int preload) 1167{ 1168 struct mod_metadata *mp, **mdp; 1169 const char *modname; 1170 int ver; 1171 1172 for (mdp = start; mdp < stop; mdp++) { 1173 mp = *mdp; 1174 if (mp->md_type != MDT_VERSION) 1175 continue; 1176 modname = mp->md_cval; 1177 ver = ((struct mod_version *)mp->md_data)->mv_version; 1178 if (modlist_lookup(modname, ver) != NULL) { 1179 printf("module %s already present!\n", modname); 1180 /* XXX what can we do? this is a build error. :-( */ 1181 continue; 1182 } 1183 modlist_newmodule(modname, ver, lf); 1184 } 1185} 1186 1187static void 1188linker_preload(void *arg) 1189{ 1190 caddr_t modptr; 1191 const char *modname, *nmodname; 1192 char *modtype; 1193 linker_file_t lf; 1194 linker_class_t lc; 1195 int error; 1196 linker_file_list_t loaded_files; 1197 linker_file_list_t depended_files; 1198 struct mod_metadata *mp, *nmp; 1199 struct mod_metadata **start, **stop, **mdp, **nmdp; 1200 struct mod_depend *verinfo; 1201 int nver; 1202 int resolves; 1203 modlist_t mod; 1204 struct sysinit **si_start, **si_stop; 1205 1206 TAILQ_INIT(&loaded_files); 1207 TAILQ_INIT(&depended_files); 1208 TAILQ_INIT(&found_modules); 1209 error = 0; 1210 1211 modptr = NULL; 1212 while ((modptr = preload_search_next_name(modptr)) != NULL) { 1213 modname = (char *)preload_search_info(modptr, MODINFO_NAME); 1214 modtype = (char *)preload_search_info(modptr, MODINFO_TYPE); 1215 if (modname == NULL) { 1216 printf("Preloaded module at %p does not have a" 1217 " name!\n", modptr); 1218 continue; 1219 } 1220 if (modtype == NULL) { 1221 printf("Preloaded module at %p does not have a type!\n", 1222 modptr); 1223 continue; 1224 } 1225 if (bootverbose) 1226 printf("Preloaded %s \"%s\" at %p.\n", modtype, modname, 1227 modptr); 1228 lf = NULL; 1229 TAILQ_FOREACH(lc, &classes, link) { 1230 error = LINKER_LINK_PRELOAD(lc, modname, &lf); 1231 if (!error) 1232 break; 1233 lf = NULL; 1234 } 1235 if (lf) 1236 TAILQ_INSERT_TAIL(&loaded_files, lf, loaded); 1237 } 1238 1239 /* 1240 * First get a list of stuff in the kernel. 1241 */ 1242 if (linker_file_lookup_set(linker_kernel_file, MDT_SETNAME, &start, 1243 &stop, NULL) == 0) 1244 linker_addmodules(linker_kernel_file, start, stop, 1); 1245 1246 /* 1247 * this is a once-off kinky bubble sort resolve relocation dependency 1248 * requirements 1249 */ 1250restart: 1251 TAILQ_FOREACH(lf, &loaded_files, loaded) { 1252 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1253 &stop, NULL); 1254 /* 1255 * First, look to see if we would successfully link with this 1256 * stuff. 1257 */ 1258 resolves = 1; /* unless we know otherwise */ 1259 if (!error) { 1260 for (mdp = start; mdp < stop; mdp++) { 1261 mp = *mdp; 1262 if (mp->md_type != MDT_DEPEND) 1263 continue; 1264 modname = mp->md_cval; 1265 verinfo = mp->md_data; 1266 for (nmdp = start; nmdp < stop; nmdp++) { 1267 nmp = *nmdp; 1268 if (nmp->md_type != MDT_VERSION) 1269 continue; 1270 nmodname = nmp->md_cval; 1271 if (strcmp(modname, nmodname) == 0) 1272 break; 1273 } 1274 if (nmdp < stop) /* it's a self reference */ 1275 continue; 1276 1277 /* 1278 * ok, the module isn't here yet, we 1279 * are not finished 1280 */ 1281 if (modlist_lookup2(modname, verinfo) == NULL) 1282 resolves = 0; 1283 } 1284 } 1285 /* 1286 * OK, if we found our modules, we can link. So, "provide" 1287 * the modules inside and add it to the end of the link order 1288 * list. 1289 */ 1290 if (resolves) { 1291 if (!error) { 1292 for (mdp = start; mdp < stop; mdp++) { 1293 mp = *mdp; 1294 if (mp->md_type != MDT_VERSION) 1295 continue; 1296 modname = mp->md_cval; 1297 nver = ((struct mod_version *) 1298 mp->md_data)->mv_version; 1299 if (modlist_lookup(modname, 1300 nver) != NULL) { 1301 printf("module %s already" 1302 " present!\n", modname); 1303 linker_file_unload(lf, 1304 LINKER_UNLOAD_FORCE); 1305 TAILQ_REMOVE(&loaded_files, 1306 lf, loaded); 1307 /* we changed tailq next ptr */ 1308 goto restart; 1309 } 1310 modlist_newmodule(modname, nver, lf); 1311 } 1312 } 1313 TAILQ_REMOVE(&loaded_files, lf, loaded); 1314 TAILQ_INSERT_TAIL(&depended_files, lf, loaded); 1315 /* 1316 * Since we provided modules, we need to restart the 1317 * sort so that the previous files that depend on us 1318 * have a chance. Also, we've busted the tailq next 1319 * pointer with the REMOVE. 1320 */ 1321 goto restart; 1322 } 1323 } 1324 1325 /* 1326 * At this point, we check to see what could not be resolved.. 1327 */ 1328 TAILQ_FOREACH(lf, &loaded_files, loaded) { 1329 printf("KLD file %s is missing dependencies\n", lf->filename); 1330 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1331 TAILQ_REMOVE(&loaded_files, lf, loaded); 1332 } 1333 1334 /* 1335 * We made it. Finish off the linking in the order we determined. 1336 */ 1337 TAILQ_FOREACH(lf, &depended_files, loaded) { 1338 if (linker_kernel_file) { 1339 linker_kernel_file->refs++; 1340 error = linker_file_add_dependency(lf, 1341 linker_kernel_file); 1342 if (error) 1343 panic("cannot add dependency"); 1344 } 1345 lf->userrefs++; /* so we can (try to) kldunload it */ 1346 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1347 &stop, NULL); 1348 if (!error) { 1349 for (mdp = start; mdp < stop; mdp++) { 1350 mp = *mdp; 1351 if (mp->md_type != MDT_DEPEND) 1352 continue; 1353 modname = mp->md_cval; 1354 verinfo = mp->md_data; 1355 mod = modlist_lookup2(modname, verinfo); 1356 /* Don't count self-dependencies */ 1357 if (lf == mod->container) 1358 continue; 1359 mod->container->refs++; 1360 error = linker_file_add_dependency(lf, 1361 mod->container); 1362 if (error) 1363 panic("cannot add dependency"); 1364 } 1365 } 1366 /* 1367 * Now do relocation etc using the symbol search paths 1368 * established by the dependencies 1369 */ 1370 error = LINKER_LINK_PRELOAD_FINISH(lf); 1371 if (error) { 1372 printf("KLD file %s - could not finalize loading\n", 1373 lf->filename); 1374 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1375 continue; 1376 } 1377 linker_file_register_modules(lf); 1378 if (linker_file_lookup_set(lf, "sysinit_set", &si_start, 1379 &si_stop, NULL) == 0) 1380 sysinit_add(si_start, si_stop); 1381 linker_file_register_sysctls(lf); 1382 lf->flags |= LINKER_FILE_LINKED; 1383 } 1384 /* woohoo! we made it! */ 1385} 1386 1387SYSINIT(preload, SI_SUB_KLD, SI_ORDER_MIDDLE, linker_preload, 0) 1388 1389/* 1390 * Search for a not-loaded module by name. 1391 * 1392 * Modules may be found in the following locations: 1393 * 1394 * - preloaded (result is just the module name) - on disk (result is full path 1395 * to module) 1396 * 1397 * If the module name is qualified in any way (contains path, etc.) the we 1398 * simply return a copy of it. 1399 * 1400 * The search path can be manipulated via sysctl. Note that we use the ';' 1401 * character as a separator to be consistent with the bootloader. 1402 */ 1403 1404static char linker_hintfile[] = "linker.hints"; 1405static char linker_path[MAXPATHLEN] = "/boot/kernel;/boot/modules"; 1406 1407SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RW, linker_path, 1408 sizeof(linker_path), "module load search path"); 1409 1410TUNABLE_STR("module_path", linker_path, sizeof(linker_path)); 1411 1412static char *linker_ext_list[] = { 1413 "", 1414 ".ko", 1415 NULL 1416}; 1417 1418/* 1419 * Check if file actually exists either with or without extension listed in 1420 * the linker_ext_list. (probably should be generic for the rest of the 1421 * kernel) 1422 */ 1423static char * 1424linker_lookup_file(const char *path, int pathlen, const char *name, 1425 int namelen, struct vattr *vap) 1426{ 1427 struct nameidata nd; 1428 struct thread *td = curthread; /* XXX */ 1429 char *result, **cpp, *sep; 1430 int error, len, extlen, reclen, flags; 1431 enum vtype type; 1432 1433 extlen = 0; 1434 for (cpp = linker_ext_list; *cpp; cpp++) { 1435 len = strlen(*cpp); 1436 if (len > extlen) 1437 extlen = len; 1438 } 1439 extlen++; /* trailing '\0' */ 1440 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1441 1442 reclen = pathlen + strlen(sep) + namelen + extlen + 1; 1443 result = malloc(reclen, M_LINKER, M_WAITOK); 1444 for (cpp = linker_ext_list; *cpp; cpp++) { 1445 snprintf(result, reclen, "%.*s%s%.*s%s", pathlen, path, sep, 1446 namelen, name, *cpp); 1447 /* 1448 * Attempt to open the file, and return the path if 1449 * we succeed and it's a regular file. 1450 */ 1451 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, result, td); 1452 flags = FREAD; 1453 error = vn_open(&nd, &flags, 0, -1); 1454 if (error == 0) { 1455 NDFREE(&nd, NDF_ONLY_PNBUF); 1456 type = nd.ni_vp->v_type; 1457 if (vap) 1458 VOP_GETATTR(nd.ni_vp, vap, td->td_ucred, td); 1459 VOP_UNLOCK(nd.ni_vp, 0, td); 1460 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 1461 if (type == VREG) 1462 return (result); 1463 } 1464 } 1465 free(result, M_LINKER); 1466 return (NULL); 1467} 1468 1469#define INT_ALIGN(base, ptr) ptr = \ 1470 (base) + (((ptr) - (base) + sizeof(int) - 1) & ~(sizeof(int) - 1)) 1471 1472/* 1473 * Lookup KLD which contains requested module in the "linker.hints" file. If 1474 * version specification is available, then try to find the best KLD. 1475 * Otherwise just find the latest one. 1476 */ 1477static char * 1478linker_hints_lookup(const char *path, int pathlen, const char *modname, 1479 int modnamelen, struct mod_depend *verinfo) 1480{ 1481 struct thread *td = curthread; /* XXX */ 1482 struct ucred *cred = td ? td->td_ucred : NULL; 1483 struct nameidata nd; 1484 struct vattr vattr, mattr; 1485 u_char *hints = NULL; 1486 u_char *cp, *recptr, *bufend, *result, *best, *pathbuf, *sep; 1487 int error, ival, bestver, *intp, reclen, found, flags, clen, blen; 1488 1489 result = NULL; 1490 bestver = found = 0; 1491 1492 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1493 reclen = imax(modnamelen, strlen(linker_hintfile)) + pathlen + 1494 strlen(sep) + 1; 1495 pathbuf = malloc(reclen, M_LINKER, M_WAITOK); 1496 snprintf(pathbuf, reclen, "%.*s%s%s", pathlen, path, sep, 1497 linker_hintfile); 1498 1499 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, pathbuf, td); 1500 flags = FREAD; 1501 error = vn_open(&nd, &flags, 0, -1); 1502 if (error) 1503 goto bad; 1504 NDFREE(&nd, NDF_ONLY_PNBUF); 1505 if (nd.ni_vp->v_type != VREG) 1506 goto bad; 1507 best = cp = NULL; 1508 error = VOP_GETATTR(nd.ni_vp, &vattr, cred, td); 1509 if (error) 1510 goto bad; 1511 /* 1512 * XXX: we need to limit this number to some reasonable value 1513 */ 1514 if (vattr.va_size > 100 * 1024) { 1515 printf("hints file too large %ld\n", (long)vattr.va_size); 1516 goto bad; 1517 } 1518 hints = malloc(vattr.va_size, M_TEMP, M_WAITOK); 1519 if (hints == NULL) 1520 goto bad; 1521 error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)hints, vattr.va_size, 0, 1522 UIO_SYSSPACE, IO_NODELOCKED, cred, NOCRED, &reclen, td); 1523 if (error) 1524 goto bad; 1525 VOP_UNLOCK(nd.ni_vp, 0, td); 1526 vn_close(nd.ni_vp, FREAD, cred, td); 1527 nd.ni_vp = NULL; 1528 if (reclen != 0) { 1529 printf("can't read %d\n", reclen); 1530 goto bad; 1531 } 1532 intp = (int *)hints; 1533 ival = *intp++; 1534 if (ival != LINKER_HINTS_VERSION) { 1535 printf("hints file version mismatch %d\n", ival); 1536 goto bad; 1537 } 1538 bufend = hints + vattr.va_size; 1539 recptr = (u_char *)intp; 1540 clen = blen = 0; 1541 while (recptr < bufend && !found) { 1542 intp = (int *)recptr; 1543 reclen = *intp++; 1544 ival = *intp++; 1545 cp = (char *)intp; 1546 switch (ival) { 1547 case MDT_VERSION: 1548 clen = *cp++; 1549 if (clen != modnamelen || bcmp(cp, modname, clen) != 0) 1550 break; 1551 cp += clen; 1552 INT_ALIGN(hints, cp); 1553 ival = *(int *)cp; 1554 cp += sizeof(int); 1555 clen = *cp++; 1556 if (verinfo == NULL || 1557 ival == verinfo->md_ver_preferred) { 1558 found = 1; 1559 break; 1560 } 1561 if (ival >= verinfo->md_ver_minimum && 1562 ival <= verinfo->md_ver_maximum && 1563 ival > bestver) { 1564 bestver = ival; 1565 best = cp; 1566 blen = clen; 1567 } 1568 break; 1569 default: 1570 break; 1571 } 1572 recptr += reclen + sizeof(int); 1573 } 1574 /* 1575 * Finally check if KLD is in the place 1576 */ 1577 if (found) 1578 result = linker_lookup_file(path, pathlen, cp, clen, &mattr); 1579 else if (best) 1580 result = linker_lookup_file(path, pathlen, best, blen, &mattr); 1581 1582 /* 1583 * KLD is newer than hints file. What we should do now? 1584 */ 1585 if (result && timespeccmp(&mattr.va_mtime, &vattr.va_mtime, >)) 1586 printf("warning: KLD '%s' is newer than the linker.hints" 1587 " file\n", result); 1588bad: 1589 free(pathbuf, M_LINKER); 1590 if (hints) 1591 free(hints, M_TEMP); 1592 if (nd.ni_vp != NULL) { 1593 VOP_UNLOCK(nd.ni_vp, 0, td); 1594 vn_close(nd.ni_vp, FREAD, cred, td); 1595 } 1596 /* 1597 * If nothing found or hints is absent - fallback to the old 1598 * way by using "kldname[.ko]" as module name. 1599 */ 1600 if (!found && !bestver && result == NULL) 1601 result = linker_lookup_file(path, pathlen, modname, 1602 modnamelen, NULL); 1603 return (result); 1604} 1605 1606/* 1607 * Lookup KLD which contains requested module in the all directories. 1608 */ 1609static char * 1610linker_search_module(const char *modname, int modnamelen, 1611 struct mod_depend *verinfo) 1612{ 1613 char *cp, *ep, *result; 1614 1615 /* 1616 * traverse the linker path 1617 */ 1618 for (cp = linker_path; *cp; cp = ep + 1) { 1619 /* find the end of this component */ 1620 for (ep = cp; (*ep != 0) && (*ep != ';'); ep++); 1621 result = linker_hints_lookup(cp, ep - cp, modname, 1622 modnamelen, verinfo); 1623 if (result != NULL) 1624 return (result); 1625 if (*ep == 0) 1626 break; 1627 } 1628 return (NULL); 1629} 1630 1631/* 1632 * Search for module in all directories listed in the linker_path. 1633 */ 1634static char * 1635linker_search_kld(const char *name) 1636{ 1637 char *cp, *ep, *result; 1638 int len; 1639 1640 /* qualified at all? */ 1641 if (index(name, '/')) 1642 return (linker_strdup(name)); 1643 1644 /* traverse the linker path */ 1645 len = strlen(name); 1646 for (ep = linker_path; *ep; ep++) { 1647 cp = ep; 1648 /* find the end of this component */ 1649 for (; *ep != 0 && *ep != ';'; ep++); 1650 result = linker_lookup_file(cp, ep - cp, name, len, NULL); 1651 if (result != NULL) 1652 return (result); 1653 } 1654 return (NULL); 1655} 1656 1657static const char * 1658linker_basename(const char *path) 1659{ 1660 const char *filename; 1661 1662 filename = rindex(path, '/'); 1663 if (filename == NULL) 1664 return path; 1665 if (filename[1]) 1666 filename++; 1667 return (filename); 1668} 1669 1670#ifdef HWPMC_HOOKS 1671 1672/* 1673 * Inform hwpmc about the set of kernel modules currently loaded. 1674 */ 1675void * 1676linker_hwpmc_list_objects(void) 1677{ 1678 int nobjects, nmappings; 1679 linker_file_t lf; 1680 struct pmckern_map_in *ko, *kobase; 1681 1682 nmappings = 15; /* a reasonable default */ 1683 1684 retry: 1685 /* allocate nmappings+1 entries */ 1686 MALLOC(kobase, struct pmckern_map_in *, 1687 (nmappings + 1) * sizeof(struct pmckern_map_in), M_LINKER, 1688 M_WAITOK | M_ZERO); 1689 1690 nobjects = 0; 1691 mtx_lock(&kld_mtx); 1692 TAILQ_FOREACH(lf, &linker_files, link) 1693 nobjects++; 1694 1695 KASSERT(nobjects > 0, ("linker_hpwmc_list_objects: no kernel " 1696 "objects?")); 1697 1698 if (nobjects > nmappings) { 1699 nmappings = nobjects; 1700 FREE(kobase, M_LINKER); 1701 mtx_unlock(&kld_mtx); 1702 goto retry; 1703 } 1704 1705 ko = kobase; 1706 TAILQ_FOREACH(lf, &linker_files, link) { 1707 ko->pm_file = lf->filename; 1708 ko->pm_address = (uintptr_t) lf->address; 1709 ko++; 1710 } 1711 1712 /* The last entry of the malloced area comprises of all zeros. */ 1713 KASSERT(ko->pm_file == NULL, 1714 ("linker_hwpmc_list_objects: last object not NULL")); 1715 1716 mtx_unlock(&kld_mtx); 1717 1718 return ((void *) kobase); 1719} 1720#endif 1721 1722/* 1723 * Find a file which contains given module and load it, if "parent" is not 1724 * NULL, register a reference to it. 1725 */ 1726int 1727linker_load_module(const char *kldname, const char *modname, 1728 struct linker_file *parent, struct mod_depend *verinfo, 1729 struct linker_file **lfpp) 1730{ 1731 linker_file_t lfdep; 1732 const char *filename; 1733 char *pathname; 1734 int error; 1735 1736 if (modname == NULL) { 1737 /* 1738 * We have to load KLD 1739 */ 1740 KASSERT(verinfo == NULL, ("linker_load_module: verinfo" 1741 " is not NULL")); 1742 pathname = linker_search_kld(kldname); 1743 } else { 1744 if (modlist_lookup2(modname, verinfo) != NULL) 1745 return (EEXIST); 1746 if (kldname != NULL) 1747 pathname = linker_strdup(kldname); 1748 else if (rootvnode == NULL) 1749 pathname = NULL; 1750 else 1751 /* 1752 * Need to find a KLD with required module 1753 */ 1754 pathname = linker_search_module(modname, 1755 strlen(modname), verinfo); 1756 } 1757 if (pathname == NULL) 1758 return (ENOENT); 1759 1760 /* 1761 * Can't load more than one file with the same basename XXX: 1762 * Actually it should be possible to have multiple KLDs with 1763 * the same basename but different path because they can 1764 * provide different versions of the same modules. 1765 */ 1766 filename = linker_basename(pathname); 1767 if (linker_find_file_by_name(filename)) { 1768 error = EEXIST; 1769 goto out; 1770 } 1771 do { 1772 error = linker_load_file(pathname, &lfdep); 1773 if (error) 1774 break; 1775 if (modname && verinfo && 1776 modlist_lookup2(modname, verinfo) == NULL) { 1777 linker_file_unload(lfdep, LINKER_UNLOAD_FORCE); 1778 error = ENOENT; 1779 break; 1780 } 1781 if (parent) { 1782 error = linker_file_add_dependency(parent, lfdep); 1783 if (error) 1784 break; 1785 } 1786 if (lfpp) 1787 *lfpp = lfdep; 1788 } while (0); 1789out: 1790 if (pathname) 1791 free(pathname, M_LINKER); 1792 return (error); 1793} 1794 1795/* 1796 * This routine is responsible for finding dependencies of userland initiated 1797 * kldload(2)'s of files. 1798 */ 1799int 1800linker_load_dependencies(linker_file_t lf) 1801{ 1802 linker_file_t lfdep; 1803 struct mod_metadata **start, **stop, **mdp, **nmdp; 1804 struct mod_metadata *mp, *nmp; 1805 struct mod_depend *verinfo; 1806 modlist_t mod; 1807 const char *modname, *nmodname; 1808 int ver, error = 0, count; 1809 1810 /* 1811 * All files are dependant on /kernel. 1812 */ 1813 if (linker_kernel_file) { 1814 linker_kernel_file->refs++; 1815 error = linker_file_add_dependency(lf, linker_kernel_file); 1816 if (error) 1817 return (error); 1818 } 1819 if (linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop, 1820 &count) != 0) 1821 return (0); 1822 for (mdp = start; mdp < stop; mdp++) { 1823 mp = *mdp; 1824 if (mp->md_type != MDT_VERSION) 1825 continue; 1826 modname = mp->md_cval; 1827 ver = ((struct mod_version *)mp->md_data)->mv_version; 1828 mod = modlist_lookup(modname, ver); 1829 if (mod != NULL) { 1830 printf("interface %s.%d already present in the KLD" 1831 " '%s'!\n", modname, ver, 1832 mod->container->filename); 1833 return (EEXIST); 1834 } 1835 } 1836 1837 for (mdp = start; mdp < stop; mdp++) { 1838 mp = *mdp; 1839 if (mp->md_type != MDT_DEPEND) 1840 continue; 1841 modname = mp->md_cval; 1842 verinfo = mp->md_data; 1843 nmodname = NULL; 1844 for (nmdp = start; nmdp < stop; nmdp++) { 1845 nmp = *nmdp; 1846 if (nmp->md_type != MDT_VERSION) 1847 continue; 1848 nmodname = nmp->md_cval; 1849 if (strcmp(modname, nmodname) == 0) 1850 break; 1851 } 1852 if (nmdp < stop)/* early exit, it's a self reference */ 1853 continue; 1854 mod = modlist_lookup2(modname, verinfo); 1855 if (mod) { /* woohoo, it's loaded already */ 1856 lfdep = mod->container; 1857 lfdep->refs++; 1858 error = linker_file_add_dependency(lf, lfdep); 1859 if (error) 1860 break; 1861 continue; 1862 } 1863 error = linker_load_module(NULL, modname, lf, verinfo, NULL); 1864 if (error) { 1865 printf("KLD %s: depends on %s - not available\n", 1866 lf->filename, modname); 1867 break; 1868 } 1869 } 1870 1871 if (error) 1872 return (error); 1873 linker_addmodules(lf, start, stop, 0); 1874 return (error); 1875} 1876 1877static int 1878sysctl_kern_function_list_iterate(const char *name, void *opaque) 1879{ 1880 struct sysctl_req *req; 1881 1882 req = opaque; 1883 return (SYSCTL_OUT(req, name, strlen(name) + 1)); 1884} 1885 1886/* 1887 * Export a nul-separated, double-nul-terminated list of all function names 1888 * in the kernel. 1889 */ 1890static int 1891sysctl_kern_function_list(SYSCTL_HANDLER_ARGS) 1892{ 1893 linker_file_t lf; 1894 int error; 1895 1896#ifdef MAC 1897 error = mac_check_kld_stat(req->td->td_ucred); 1898 if (error) 1899 return (error); 1900#endif 1901 error = sysctl_wire_old_buffer(req, 0); 1902 if (error != 0) 1903 return (error); 1904 mtx_lock(&kld_mtx); 1905 TAILQ_FOREACH(lf, &linker_files, link) { 1906 error = LINKER_EACH_FUNCTION_NAME(lf, 1907 sysctl_kern_function_list_iterate, req); 1908 if (error) { 1909 mtx_unlock(&kld_mtx); 1910 return (error); 1911 } 1912 } 1913 mtx_unlock(&kld_mtx); 1914 return (SYSCTL_OUT(req, "", 1)); 1915} 1916 1917SYSCTL_PROC(_kern, OID_AUTO, function_list, CTLFLAG_RD, 1918 NULL, 0, sysctl_kern_function_list, "", "kernel function list"); 1919