Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)
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FreeBSD/Linux Kernel Cross Reference
sys/kern/kern_linker.c
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1 /*- 2 * Copyright (c) 1997-2000 Doug Rabson 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD: releng/5.3/sys/kern/kern_linker.c 136588 2004-10-16 08:43:07Z cvs2svn $"); 29 30 #include "opt_ddb.h" 31 #include "opt_mac.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/proc.h> 40 #include <sys/lock.h> 41 #include <sys/mutex.h> 42 #include <sys/sx.h> 43 #include <sys/mac.h> 44 #include <sys/module.h> 45 #include <sys/linker.h> 46 #include <sys/fcntl.h> 47 #include <sys/libkern.h> 48 #include <sys/namei.h> 49 #include <sys/vnode.h> 50 #include <sys/sysctl.h> 51 52 #include "linker_if.h" 53 54 #ifdef KLD_DEBUG 55 int kld_debug = 0; 56 #endif 57 58 /* 59 * static char *linker_search_path(const char *name, struct mod_depend 60 * *verinfo); 61 */ 62 static const char *linker_basename(const char *path); 63 64 /* Metadata from the static kernel */ 65 SET_DECLARE(modmetadata_set, struct mod_metadata); 66 67 MALLOC_DEFINE(M_LINKER, "linker", "kernel linker"); 68 69 linker_file_t linker_kernel_file; 70 71 static struct mtx kld_mtx; /* kernel linker mutex */ 72 73 static linker_class_list_t classes; 74 static linker_file_list_t linker_files; 75 static int next_file_id = 1; 76 static int linker_no_more_classes = 0; 77 78 #define LINKER_GET_NEXT_FILE_ID(a) do { \ 79 linker_file_t lftmp; \ 80 \ 81 retry: \ 82 mtx_lock(&kld_mtx); \ 83 TAILQ_FOREACH(lftmp, &linker_files, link) { \ 84 if (next_file_id == lftmp->id) { \ 85 next_file_id++; \ 86 mtx_unlock(&kld_mtx); \ 87 goto retry; \ 88 } \ 89 } \ 90 (a) = next_file_id; \ 91 mtx_unlock(&kld_mtx); /* Hold for safe read of id variable */ \ 92 } while(0) 93 94 95 /* XXX wrong name; we're looking at version provision tags here, not modules */ 96 typedef TAILQ_HEAD(, modlist) modlisthead_t; 97 struct modlist { 98 TAILQ_ENTRY(modlist) link; /* chain together all modules */ 99 linker_file_t container; 100 const char *name; 101 int version; 102 }; 103 typedef struct modlist *modlist_t; 104 static modlisthead_t found_modules; 105 106 static modlist_t modlist_lookup2(const char *name, 107 struct mod_depend *verinfo); 108 109 static char * 110 linker_strdup(const char *str) 111 { 112 char *result; 113 114 if ((result = malloc((strlen(str) + 1), M_LINKER, M_WAITOK)) != NULL) 115 strcpy(result, str); 116 return (result); 117 } 118 119 static void 120 linker_init(void *arg) 121 { 122 123 mtx_init(&kld_mtx, "kernel linker", NULL, MTX_DEF); 124 TAILQ_INIT(&classes); 125 TAILQ_INIT(&linker_files); 126 } 127 128 SYSINIT(linker, SI_SUB_KLD, SI_ORDER_FIRST, linker_init, 0) 129 130 static void 131 linker_stop_class_add(void *arg) 132 { 133 134 linker_no_more_classes = 1; 135 } 136 137 SYSINIT(linker_class, SI_SUB_KLD, SI_ORDER_ANY, linker_stop_class_add, NULL) 138 139 int 140 linker_add_class(linker_class_t lc) 141 { 142 143 /* 144 * We disallow any class registration passt SI_ORDER_ANY 145 * of SI_SUB_KLD. 146 */ 147 if (linker_no_more_classes == 1) 148 return (EPERM); 149 kobj_class_compile((kobj_class_t) lc); 150 ((kobj_class_t)lc)->refs++; /* prevent ops being freed */ 151 TAILQ_INSERT_TAIL(&classes, lc, link); 152 return (0); 153 } 154 155 static void 156 linker_file_sysinit(linker_file_t lf) 157 { 158 struct sysinit **start, **stop, **sipp, **xipp, *save; 159 160 KLD_DPF(FILE, ("linker_file_sysinit: calling SYSINITs for %s\n", 161 lf->filename)); 162 163 if (linker_file_lookup_set(lf, "sysinit_set", &start, &stop, NULL) != 0) 164 return; 165 /* 166 * Perform a bubble sort of the system initialization objects by 167 * their subsystem (primary key) and order (secondary key). 168 * 169 * Since some things care about execution order, this is the operation 170 * which ensures continued function. 171 */ 172 for (sipp = start; sipp < stop; sipp++) { 173 for (xipp = sipp + 1; xipp < stop; xipp++) { 174 if ((*sipp)->subsystem < (*xipp)->subsystem || 175 ((*sipp)->subsystem == (*xipp)->subsystem && 176 (*sipp)->order <= (*xipp)->order)) 177 continue; /* skip */ 178 save = *sipp; 179 *sipp = *xipp; 180 *xipp = save; 181 } 182 } 183 184 /* 185 * Traverse the (now) ordered list of system initialization tasks. 186 * Perform each task, and continue on to the next task. 187 */ 188 for (sipp = start; sipp < stop; sipp++) { 189 if ((*sipp)->subsystem == SI_SUB_DUMMY) 190 continue; /* skip dummy task(s) */ 191 192 /* Call function */ 193 (*((*sipp)->func)) ((*sipp)->udata); 194 } 195 } 196 197 static void 198 linker_file_sysuninit(linker_file_t lf) 199 { 200 struct sysinit **start, **stop, **sipp, **xipp, *save; 201 202 KLD_DPF(FILE, ("linker_file_sysuninit: calling SYSUNINITs for %s\n", 203 lf->filename)); 204 205 if (linker_file_lookup_set(lf, "sysuninit_set", &start, &stop, 206 NULL) != 0) 207 return; 208 209 /* 210 * Perform a reverse bubble sort of the system initialization objects 211 * by their subsystem (primary key) and order (secondary key). 212 * 213 * Since some things care about execution order, this is the operation 214 * which ensures continued function. 215 */ 216 for (sipp = start; sipp < stop; sipp++) { 217 for (xipp = sipp + 1; xipp < stop; xipp++) { 218 if ((*sipp)->subsystem > (*xipp)->subsystem || 219 ((*sipp)->subsystem == (*xipp)->subsystem && 220 (*sipp)->order >= (*xipp)->order)) 221 continue; /* skip */ 222 save = *sipp; 223 *sipp = *xipp; 224 *xipp = save; 225 } 226 } 227 228 /* 229 * Traverse the (now) ordered list of system initialization tasks. 230 * Perform each task, and continue on to the next task. 231 */ 232 for (sipp = start; sipp < stop; sipp++) { 233 if ((*sipp)->subsystem == SI_SUB_DUMMY) 234 continue; /* skip dummy task(s) */ 235 236 /* Call function */ 237 (*((*sipp)->func)) ((*sipp)->udata); 238 } 239 } 240 241 static void 242 linker_file_register_sysctls(linker_file_t lf) 243 { 244 struct sysctl_oid **start, **stop, **oidp; 245 246 KLD_DPF(FILE, 247 ("linker_file_register_sysctls: registering SYSCTLs for %s\n", 248 lf->filename)); 249 250 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0) 251 return; 252 253 for (oidp = start; oidp < stop; oidp++) 254 sysctl_register_oid(*oidp); 255 } 256 257 static void 258 linker_file_unregister_sysctls(linker_file_t lf) 259 { 260 struct sysctl_oid **start, **stop, **oidp; 261 262 KLD_DPF(FILE, ("linker_file_unregister_sysctls: registering SYSCTLs" 263 " for %s\n", lf->filename)); 264 265 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0) 266 return; 267 268 for (oidp = start; oidp < stop; oidp++) 269 sysctl_unregister_oid(*oidp); 270 } 271 272 static int 273 linker_file_register_modules(linker_file_t lf) 274 { 275 struct mod_metadata **start, **stop, **mdp; 276 const moduledata_t *moddata; 277 int error; 278 279 KLD_DPF(FILE, ("linker_file_register_modules: registering modules" 280 " in %s\n", lf->filename)); 281 282 if (linker_file_lookup_set(lf, "modmetadata_set", &start, 283 &stop, 0) != 0) { 284 /* 285 * This fallback should be unnecessary, but if we get booted 286 * from boot2 instead of loader and we are missing our 287 * metadata then we have to try the best we can. 288 */ 289 if (lf == linker_kernel_file) { 290 start = SET_BEGIN(modmetadata_set); 291 stop = SET_LIMIT(modmetadata_set); 292 } else 293 return (0); 294 } 295 for (mdp = start; mdp < stop; mdp++) { 296 if ((*mdp)->md_type != MDT_MODULE) 297 continue; 298 moddata = (*mdp)->md_data; 299 KLD_DPF(FILE, ("Registering module %s in %s\n", 300 moddata->name, lf->filename)); 301 error = module_register(moddata, lf); 302 if (error) 303 printf("Module %s failed to register: %d\n", 304 moddata->name, error); 305 } 306 return (0); 307 } 308 309 static void 310 linker_init_kernel_modules(void) 311 { 312 313 linker_file_register_modules(linker_kernel_file); 314 } 315 316 SYSINIT(linker_kernel, SI_SUB_KLD, SI_ORDER_ANY, linker_init_kernel_modules, 0) 317 318 static int 319 linker_load_file(const char *filename, linker_file_t *result) 320 { 321 linker_class_t lc; 322 linker_file_t lf; 323 int foundfile, error = 0; 324 325 /* Refuse to load modules if securelevel raised */ 326 if (securelevel > 0) 327 return (EPERM); 328 329 lf = linker_find_file_by_name(filename); 330 if (lf) { 331 KLD_DPF(FILE, ("linker_load_file: file %s is already loaded," 332 " incrementing refs\n", filename)); 333 *result = lf; 334 lf->refs++; 335 goto out; 336 } 337 lf = NULL; 338 foundfile = 0; 339 340 /* 341 * We do not need to protect (lock) classes here because there is 342 * no class registration past startup (SI_SUB_KLD, SI_ORDER_ANY) 343 * and there is no class deregistration mechanism at this time. 344 */ 345 TAILQ_FOREACH(lc, &classes, link) { 346 KLD_DPF(FILE, ("linker_load_file: trying to load %s\n", 347 filename)); 348 error = LINKER_LOAD_FILE(lc, filename, &lf); 349 /* 350 * If we got something other than ENOENT, then it exists but 351 * we cannot load it for some other reason. 352 */ 353 if (error != ENOENT) 354 foundfile = 1; 355 if (lf) { 356 linker_file_register_modules(lf); 357 linker_file_register_sysctls(lf); 358 linker_file_sysinit(lf); 359 lf->flags |= LINKER_FILE_LINKED; 360 *result = lf; 361 error = 0; 362 goto out; 363 } 364 } 365 /* 366 * Less than ideal, but tells the user whether it failed to load or 367 * the module was not found. 368 */ 369 if (foundfile) { 370 /* 371 * Format not recognized or otherwise unloadable. 372 * When loading a module that is statically built into 373 * the kernel EEXIST percolates back up as the return 374 * value. Preserve this so that apps like sysinstall 375 * can recognize this special case and not post bogus 376 * dialog boxes. 377 */ 378 if (error != EEXIST) 379 error = ENOEXEC; 380 } else 381 error = ENOENT; /* Nothing found */ 382 out: 383 return (error); 384 } 385 386 int 387 linker_reference_module(const char *modname, struct mod_depend *verinfo, 388 linker_file_t *result) 389 { 390 modlist_t mod; 391 392 if ((mod = modlist_lookup2(modname, verinfo)) != NULL) { 393 *result = mod->container; 394 (*result)->refs++; 395 return (0); 396 } 397 398 return (linker_load_module(NULL, modname, NULL, verinfo, result)); 399 } 400 401 linker_file_t 402 linker_find_file_by_name(const char *filename) 403 { 404 linker_file_t lf = 0; 405 char *koname; 406 407 koname = malloc(strlen(filename) + 4, M_LINKER, M_WAITOK); 408 if (koname == NULL) 409 goto out; 410 sprintf(koname, "%s.ko", filename); 411 412 mtx_lock(&kld_mtx); 413 TAILQ_FOREACH(lf, &linker_files, link) { 414 if (strcmp(lf->filename, koname) == 0) 415 break; 416 if (strcmp(lf->filename, filename) == 0) 417 break; 418 } 419 mtx_unlock(&kld_mtx); 420 out: 421 if (koname) 422 free(koname, M_LINKER); 423 return (lf); 424 } 425 426 linker_file_t 427 linker_find_file_by_id(int fileid) 428 { 429 linker_file_t lf = 0; 430 431 mtx_lock(&kld_mtx); 432 TAILQ_FOREACH(lf, &linker_files, link) 433 if (lf->id == fileid) 434 break; 435 mtx_unlock(&kld_mtx); 436 return (lf); 437 } 438 439 linker_file_t 440 linker_make_file(const char *pathname, linker_class_t lc) 441 { 442 linker_file_t lf; 443 const char *filename; 444 445 lf = NULL; 446 filename = linker_basename(pathname); 447 448 KLD_DPF(FILE, ("linker_make_file: new file, filename=%s\n", filename)); 449 lf = (linker_file_t)kobj_create((kobj_class_t)lc, M_LINKER, M_WAITOK); 450 if (lf == NULL) 451 goto out; 452 lf->refs = 1; 453 lf->userrefs = 0; 454 lf->flags = 0; 455 lf->filename = linker_strdup(filename); 456 LINKER_GET_NEXT_FILE_ID(lf->id); 457 lf->ndeps = 0; 458 lf->deps = NULL; 459 STAILQ_INIT(&lf->common); 460 TAILQ_INIT(&lf->modules); 461 mtx_lock(&kld_mtx); 462 TAILQ_INSERT_TAIL(&linker_files, lf, link); 463 mtx_unlock(&kld_mtx); 464 out: 465 return (lf); 466 } 467 468 int 469 linker_file_unload(linker_file_t file, int flags) 470 { 471 module_t mod, next; 472 modlist_t ml, nextml; 473 struct common_symbol *cp; 474 int error, i; 475 476 error = 0; 477 478 /* Refuse to unload modules if securelevel raised. */ 479 if (securelevel > 0) 480 return (EPERM); 481 #ifdef MAC 482 error = mac_check_kld_unload(curthread->td_ucred); 483 if (error) 484 return (error); 485 #endif 486 487 KLD_DPF(FILE, ("linker_file_unload: lf->refs=%d\n", file->refs)); 488 if (file->refs == 1) { 489 KLD_DPF(FILE, ("linker_file_unload: file is unloading," 490 " informing modules\n")); 491 492 /* 493 * Inform any modules associated with this file. 494 */ 495 MOD_XLOCK; 496 for (mod = TAILQ_FIRST(&file->modules); mod; mod = next) { 497 next = module_getfnext(mod); 498 MOD_XUNLOCK; 499 500 /* 501 * Give the module a chance to veto the unload. 502 */ 503 if ((error = module_unload(mod, flags)) != 0) { 504 KLD_DPF(FILE, ("linker_file_unload: module %p" 505 " vetoes unload\n", mod)); 506 goto out; 507 } else 508 MOD_XLOCK; 509 module_release(mod); 510 } 511 MOD_XUNLOCK; 512 } 513 file->refs--; 514 if (file->refs > 0) { 515 goto out; 516 } 517 for (ml = TAILQ_FIRST(&found_modules); ml; ml = nextml) { 518 nextml = TAILQ_NEXT(ml, link); 519 if (ml->container == file) { 520 TAILQ_REMOVE(&found_modules, ml, link); 521 free(ml, M_LINKER); 522 } 523 } 524 525 /* 526 * Don't try to run SYSUNINITs if we are unloaded due to a 527 * link error. 528 */ 529 if (file->flags & LINKER_FILE_LINKED) { 530 linker_file_sysuninit(file); 531 linker_file_unregister_sysctls(file); 532 } 533 mtx_lock(&kld_mtx); 534 TAILQ_REMOVE(&linker_files, file, link); 535 mtx_unlock(&kld_mtx); 536 537 if (file->deps) { 538 for (i = 0; i < file->ndeps; i++) 539 linker_file_unload(file->deps[i], flags); 540 free(file->deps, M_LINKER); 541 file->deps = NULL; 542 } 543 for (cp = STAILQ_FIRST(&file->common); cp; 544 cp = STAILQ_FIRST(&file->common)) { 545 STAILQ_REMOVE(&file->common, cp, common_symbol, link); 546 free(cp, M_LINKER); 547 } 548 549 LINKER_UNLOAD(file); 550 if (file->filename) { 551 free(file->filename, M_LINKER); 552 file->filename = NULL; 553 } 554 kobj_delete((kobj_t) file, M_LINKER); 555 out: 556 return (error); 557 } 558 559 int 560 linker_file_add_dependency(linker_file_t file, linker_file_t dep) 561 { 562 linker_file_t *newdeps; 563 564 newdeps = malloc((file->ndeps + 1) * sizeof(linker_file_t *), 565 M_LINKER, M_WAITOK | M_ZERO); 566 if (newdeps == NULL) 567 return (ENOMEM); 568 569 if (file->deps) { 570 bcopy(file->deps, newdeps, 571 file->ndeps * sizeof(linker_file_t *)); 572 free(file->deps, M_LINKER); 573 } 574 file->deps = newdeps; 575 file->deps[file->ndeps] = dep; 576 file->ndeps++; 577 return (0); 578 } 579 580 /* 581 * Locate a linker set and its contents. This is a helper function to avoid 582 * linker_if.h exposure elsewhere. Note: firstp and lastp are really void *** 583 */ 584 int 585 linker_file_lookup_set(linker_file_t file, const char *name, 586 void *firstp, void *lastp, int *countp) 587 { 588 589 return (LINKER_LOOKUP_SET(file, name, firstp, lastp, countp)); 590 } 591 592 caddr_t 593 linker_file_lookup_symbol(linker_file_t file, const char *name, int deps) 594 { 595 c_linker_sym_t sym; 596 linker_symval_t symval; 597 caddr_t address; 598 size_t common_size = 0; 599 int i; 600 601 KLD_DPF(SYM, ("linker_file_lookup_symbol: file=%p, name=%s, deps=%d\n", 602 file, name, deps)); 603 604 if (LINKER_LOOKUP_SYMBOL(file, name, &sym) == 0) { 605 LINKER_SYMBOL_VALUES(file, sym, &symval); 606 if (symval.value == 0) 607 /* 608 * For commons, first look them up in the 609 * dependencies and only allocate space if not found 610 * there. 611 */ 612 common_size = symval.size; 613 else { 614 KLD_DPF(SYM, ("linker_file_lookup_symbol: symbol" 615 ".value=%p\n", symval.value)); 616 return (symval.value); 617 } 618 } 619 if (deps) { 620 for (i = 0; i < file->ndeps; i++) { 621 address = linker_file_lookup_symbol(file->deps[i], 622 name, 0); 623 if (address) { 624 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 625 " deps value=%p\n", address)); 626 return (address); 627 } 628 } 629 } 630 if (common_size > 0) { 631 /* 632 * This is a common symbol which was not found in the 633 * dependencies. We maintain a simple common symbol table in 634 * the file object. 635 */ 636 struct common_symbol *cp; 637 638 STAILQ_FOREACH(cp, &file->common, link) { 639 if (strcmp(cp->name, name) == 0) { 640 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 641 " old common value=%p\n", cp->address)); 642 return (cp->address); 643 } 644 } 645 /* 646 * Round the symbol size up to align. 647 */ 648 common_size = (common_size + sizeof(int) - 1) & -sizeof(int); 649 cp = malloc(sizeof(struct common_symbol) 650 + common_size + strlen(name) + 1, M_LINKER, 651 M_WAITOK | M_ZERO); 652 if (cp == NULL) { 653 KLD_DPF(SYM, ("linker_file_lookup_symbol: nomem\n")); 654 return (0); 655 } 656 cp->address = (caddr_t)(cp + 1); 657 cp->name = cp->address + common_size; 658 strcpy(cp->name, name); 659 bzero(cp->address, common_size); 660 STAILQ_INSERT_TAIL(&file->common, cp, link); 661 662 KLD_DPF(SYM, ("linker_file_lookup_symbol: new common" 663 " value=%p\n", cp->address)); 664 return (cp->address); 665 } 666 KLD_DPF(SYM, ("linker_file_lookup_symbol: fail\n")); 667 return (0); 668 } 669 670 #ifdef DDB 671 /* 672 * DDB Helpers. DDB has to look across multiple files with their own symbol 673 * tables and string tables. 674 * 675 * Note that we do not obey list locking protocols here. We really don't need 676 * DDB to hang because somebody's got the lock held. We'll take the chance 677 * that the files list is inconsistant instead. 678 */ 679 680 int 681 linker_ddb_lookup(const char *symstr, c_linker_sym_t *sym) 682 { 683 linker_file_t lf; 684 685 TAILQ_FOREACH(lf, &linker_files, link) { 686 if (LINKER_LOOKUP_SYMBOL(lf, symstr, sym) == 0) 687 return (0); 688 } 689 return (ENOENT); 690 } 691 692 int 693 linker_ddb_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) 694 { 695 linker_file_t lf; 696 c_linker_sym_t best, es; 697 u_long diff, bestdiff, off; 698 699 best = 0; 700 off = (uintptr_t)value; 701 bestdiff = off; 702 TAILQ_FOREACH(lf, &linker_files, link) { 703 if (LINKER_SEARCH_SYMBOL(lf, value, &es, &diff) != 0) 704 continue; 705 if (es != 0 && diff < bestdiff) { 706 best = es; 707 bestdiff = diff; 708 } 709 if (bestdiff == 0) 710 break; 711 } 712 if (best) { 713 *sym = best; 714 *diffp = bestdiff; 715 return (0); 716 } else { 717 *sym = 0; 718 *diffp = off; 719 return (ENOENT); 720 } 721 } 722 723 int 724 linker_ddb_symbol_values(c_linker_sym_t sym, linker_symval_t *symval) 725 { 726 linker_file_t lf; 727 728 TAILQ_FOREACH(lf, &linker_files, link) { 729 if (LINKER_SYMBOL_VALUES(lf, sym, symval) == 0) 730 return (0); 731 } 732 return (ENOENT); 733 } 734 #endif 735 736 /* 737 * Syscalls. 738 */ 739 /* 740 * MPSAFE 741 */ 742 int 743 kldload(struct thread *td, struct kldload_args *uap) 744 { 745 char *kldname, *modname; 746 char *pathname = NULL; 747 linker_file_t lf; 748 int error = 0; 749 750 td->td_retval[0] = -1; 751 752 mtx_lock(&Giant); 753 754 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 755 goto out; 756 757 if ((error = suser(td)) != 0) 758 goto out; 759 760 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 761 if ((error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL)) != 0) 762 goto out; 763 764 /* 765 * If path do 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(pathname, '/') || index(pathname, '.')) { 770 kldname = pathname; 771 modname = NULL; 772 } else { 773 kldname = NULL; 774 modname = pathname; 775 } 776 error = linker_load_module(kldname, modname, NULL, NULL, &lf); 777 if (error) 778 goto out; 779 780 lf->userrefs++; 781 td->td_retval[0] = lf->id; 782 out: 783 if (pathname) 784 free(pathname, M_TEMP); 785 mtx_unlock(&Giant); 786 return (error); 787 } 788 789 /* 790 * MPSAFE 791 */ 792 static int 793 kern_kldunload(struct thread *td, int fileid, int flags) 794 { 795 linker_file_t lf; 796 int error = 0; 797 798 mtx_lock(&Giant); 799 800 if ((error = securelevel_gt(td->td_ucred, 0)) != 0) 801 goto out; 802 803 if ((error = suser(td)) != 0) 804 goto out; 805 806 lf = linker_find_file_by_id(fileid); 807 if (lf) { 808 KLD_DPF(FILE, ("kldunload: lf->userrefs=%d\n", lf->userrefs)); 809 if (lf->userrefs == 0) { 810 /* 811 * XXX: maybe LINKER_UNLOAD_FORCE should override ? 812 */ 813 printf("kldunload: attempt to unload file that was" 814 " loaded by the kernel\n"); 815 error = EBUSY; 816 goto out; 817 } 818 lf->userrefs--; 819 error = linker_file_unload(lf, flags); 820 if (error) 821 lf->userrefs++; 822 } else 823 error = ENOENT; 824 out: 825 mtx_unlock(&Giant); 826 return (error); 827 } 828 829 /* 830 * MPSAFE 831 */ 832 int 833 kldunload(struct thread *td, struct kldunload_args *uap) 834 { 835 836 return (kern_kldunload(td, uap->fileid, LINKER_UNLOAD_NORMAL)); 837 } 838 839 /* 840 * MPSAFE 841 */ 842 int 843 kldunloadf(struct thread *td, struct kldunloadf_args *uap) 844 { 845 846 if (uap->flags != LINKER_UNLOAD_NORMAL && 847 uap->flags != LINKER_UNLOAD_FORCE) 848 return (EINVAL); 849 return (kern_kldunload(td, uap->fileid, uap->flags)); 850 } 851 852 /* 853 * MPSAFE 854 */ 855 int 856 kldfind(struct thread *td, struct kldfind_args *uap) 857 { 858 char *pathname; 859 const char *filename; 860 linker_file_t lf; 861 int error = 0; 862 863 #ifdef MAC 864 error = mac_check_kld_stat(td->td_ucred); 865 if (error) 866 return (error); 867 #endif 868 869 mtx_lock(&Giant); 870 td->td_retval[0] = -1; 871 872 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 873 if ((error = copyinstr(uap->file, pathname, MAXPATHLEN, NULL)) != 0) 874 goto out; 875 876 filename = linker_basename(pathname); 877 lf = linker_find_file_by_name(filename); 878 if (lf) 879 td->td_retval[0] = lf->id; 880 else 881 error = ENOENT; 882 out: 883 if (pathname) 884 free(pathname, M_TEMP); 885 mtx_unlock(&Giant); 886 return (error); 887 } 888 889 /* 890 * MPSAFE 891 */ 892 int 893 kldnext(struct thread *td, struct kldnext_args *uap) 894 { 895 linker_file_t lf; 896 int error = 0; 897 898 #ifdef MAC 899 error = mac_check_kld_stat(td->td_ucred); 900 if (error) 901 return (error); 902 #endif 903 904 mtx_lock(&Giant); 905 906 if (uap->fileid == 0) { 907 mtx_lock(&kld_mtx); 908 if (TAILQ_FIRST(&linker_files)) 909 td->td_retval[0] = TAILQ_FIRST(&linker_files)->id; 910 else 911 td->td_retval[0] = 0; 912 mtx_unlock(&kld_mtx); 913 goto out; 914 } 915 lf = linker_find_file_by_id(uap->fileid); 916 if (lf) { 917 if (TAILQ_NEXT(lf, link)) 918 td->td_retval[0] = TAILQ_NEXT(lf, link)->id; 919 else 920 td->td_retval[0] = 0; 921 } else 922 error = ENOENT; 923 out: 924 mtx_unlock(&Giant); 925 return (error); 926 } 927 928 /* 929 * MPSAFE 930 */ 931 int 932 kldstat(struct thread *td, struct kldstat_args *uap) 933 { 934 linker_file_t lf; 935 int error = 0; 936 int namelen, version; 937 struct kld_file_stat *stat; 938 939 #ifdef MAC 940 error = mac_check_kld_stat(td->td_ucred); 941 if (error) 942 return (error); 943 #endif 944 945 mtx_lock(&Giant); 946 947 lf = linker_find_file_by_id(uap->fileid); 948 if (lf == NULL) { 949 error = ENOENT; 950 goto out; 951 } 952 stat = uap->stat; 953 954 /* 955 * Check the version of the user's structure. 956 */ 957 if ((error = copyin(&stat->version, &version, sizeof(version))) != 0) 958 goto out; 959 if (version != sizeof(struct kld_file_stat)) { 960 error = EINVAL; 961 goto out; 962 } 963 namelen = strlen(lf->filename) + 1; 964 if (namelen > MAXPATHLEN) 965 namelen = MAXPATHLEN; 966 if ((error = copyout(lf->filename, &stat->name[0], namelen)) != 0) 967 goto out; 968 if ((error = copyout(&lf->refs, &stat->refs, sizeof(int))) != 0) 969 goto out; 970 if ((error = copyout(&lf->id, &stat->id, sizeof(int))) != 0) 971 goto out; 972 if ((error = copyout(&lf->address, &stat->address, 973 sizeof(caddr_t))) != 0) 974 goto out; 975 if ((error = copyout(&lf->size, &stat->size, sizeof(size_t))) != 0) 976 goto out; 977 978 td->td_retval[0] = 0; 979 out: 980 mtx_unlock(&Giant); 981 return (error); 982 } 983 984 /* 985 * MPSAFE 986 */ 987 int 988 kldfirstmod(struct thread *td, struct kldfirstmod_args *uap) 989 { 990 linker_file_t lf; 991 module_t mp; 992 int error = 0; 993 994 #ifdef MAC 995 error = mac_check_kld_stat(td->td_ucred); 996 if (error) 997 return (error); 998 #endif 999 1000 mtx_lock(&Giant); 1001 lf = linker_find_file_by_id(uap->fileid); 1002 if (lf) { 1003 MOD_SLOCK; 1004 mp = TAILQ_FIRST(&lf->modules); 1005 if (mp != NULL) 1006 td->td_retval[0] = module_getid(mp); 1007 else 1008 td->td_retval[0] = 0; 1009 MOD_SUNLOCK; 1010 } else 1011 error = ENOENT; 1012 mtx_unlock(&Giant); 1013 return (error); 1014 } 1015 1016 /* 1017 * MPSAFE 1018 */ 1019 int 1020 kldsym(struct thread *td, struct kldsym_args *uap) 1021 { 1022 char *symstr = NULL; 1023 c_linker_sym_t sym; 1024 linker_symval_t symval; 1025 linker_file_t lf; 1026 struct kld_sym_lookup lookup; 1027 int error = 0; 1028 1029 #ifdef MAC 1030 error = mac_check_kld_stat(td->td_ucred); 1031 if (error) 1032 return (error); 1033 #endif 1034 1035 mtx_lock(&Giant); 1036 1037 if ((error = copyin(uap->data, &lookup, sizeof(lookup))) != 0) 1038 goto out; 1039 if (lookup.version != sizeof(lookup) || 1040 uap->cmd != KLDSYM_LOOKUP) { 1041 error = EINVAL; 1042 goto out; 1043 } 1044 symstr = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1045 if ((error = copyinstr(lookup.symname, symstr, MAXPATHLEN, NULL)) != 0) 1046 goto out; 1047 if (uap->fileid != 0) { 1048 lf = linker_find_file_by_id(uap->fileid); 1049 if (lf == NULL) { 1050 error = ENOENT; 1051 goto out; 1052 } 1053 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 1054 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 1055 lookup.symvalue = (uintptr_t) symval.value; 1056 lookup.symsize = symval.size; 1057 error = copyout(&lookup, uap->data, sizeof(lookup)); 1058 } else 1059 error = ENOENT; 1060 } else { 1061 mtx_lock(&kld_mtx); 1062 TAILQ_FOREACH(lf, &linker_files, link) { 1063 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 1064 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 1065 lookup.symvalue = (uintptr_t)symval.value; 1066 lookup.symsize = symval.size; 1067 error = copyout(&lookup, uap->data, 1068 sizeof(lookup)); 1069 break; 1070 } 1071 } 1072 mtx_unlock(&kld_mtx); 1073 if (lf == NULL) 1074 error = ENOENT; 1075 } 1076 out: 1077 if (symstr) 1078 free(symstr, M_TEMP); 1079 mtx_unlock(&Giant); 1080 return (error); 1081 } 1082 1083 /* 1084 * Preloaded module support 1085 */ 1086 1087 static modlist_t 1088 modlist_lookup(const char *name, int ver) 1089 { 1090 modlist_t mod; 1091 1092 TAILQ_FOREACH(mod, &found_modules, link) { 1093 if (strcmp(mod->name, name) == 0 && 1094 (ver == 0 || mod->version == ver)) 1095 return (mod); 1096 } 1097 return (NULL); 1098 } 1099 1100 static modlist_t 1101 modlist_lookup2(const char *name, struct mod_depend *verinfo) 1102 { 1103 modlist_t mod, bestmod; 1104 int ver; 1105 1106 if (verinfo == NULL) 1107 return (modlist_lookup(name, 0)); 1108 bestmod = NULL; 1109 for (mod = TAILQ_FIRST(&found_modules); mod; 1110 mod = TAILQ_NEXT(mod, link)) { 1111 if (strcmp(mod->name, name) != 0) 1112 continue; 1113 ver = mod->version; 1114 if (ver == verinfo->md_ver_preferred) 1115 return (mod); 1116 if (ver >= verinfo->md_ver_minimum && 1117 ver <= verinfo->md_ver_maximum && 1118 (bestmod == NULL || ver > bestmod->version)) 1119 bestmod = mod; 1120 } 1121 return (bestmod); 1122 } 1123 1124 static modlist_t 1125 modlist_newmodule(const char *modname, int version, linker_file_t container) 1126 { 1127 modlist_t mod; 1128 1129 mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT | M_ZERO); 1130 if (mod == NULL) 1131 panic("no memory for module list"); 1132 mod->container = container; 1133 mod->name = modname; 1134 mod->version = version; 1135 TAILQ_INSERT_TAIL(&found_modules, mod, link); 1136 return (mod); 1137 } 1138 1139 static void 1140 linker_addmodules(linker_file_t lf, struct mod_metadata **start, 1141 struct mod_metadata **stop, int preload) 1142 { 1143 struct mod_metadata *mp, **mdp; 1144 const char *modname; 1145 int ver; 1146 1147 for (mdp = start; mdp < stop; mdp++) { 1148 mp = *mdp; 1149 if (mp->md_type != MDT_VERSION) 1150 continue; 1151 modname = mp->md_cval; 1152 ver = ((struct mod_version *)mp->md_data)->mv_version; 1153 if (modlist_lookup(modname, ver) != NULL) { 1154 printf("module %s already present!\n", modname); 1155 /* XXX what can we do? this is a build error. :-( */ 1156 continue; 1157 } 1158 modlist_newmodule(modname, ver, lf); 1159 } 1160 } 1161 1162 static void 1163 linker_preload(void *arg) 1164 { 1165 caddr_t modptr; 1166 const char *modname, *nmodname; 1167 char *modtype; 1168 linker_file_t lf; 1169 linker_class_t lc; 1170 int error; 1171 linker_file_list_t loaded_files; 1172 linker_file_list_t depended_files; 1173 struct mod_metadata *mp, *nmp; 1174 struct mod_metadata **start, **stop, **mdp, **nmdp; 1175 struct mod_depend *verinfo; 1176 int nver; 1177 int resolves; 1178 modlist_t mod; 1179 struct sysinit **si_start, **si_stop; 1180 1181 TAILQ_INIT(&loaded_files); 1182 TAILQ_INIT(&depended_files); 1183 TAILQ_INIT(&found_modules); 1184 error = 0; 1185 1186 modptr = NULL; 1187 while ((modptr = preload_search_next_name(modptr)) != NULL) { 1188 modname = (char *)preload_search_info(modptr, MODINFO_NAME); 1189 modtype = (char *)preload_search_info(modptr, MODINFO_TYPE); 1190 if (modname == NULL) { 1191 printf("Preloaded module at %p does not have a" 1192 " name!\n", modptr); 1193 continue; 1194 } 1195 if (modtype == NULL) { 1196 printf("Preloaded module at %p does not have a type!\n", 1197 modptr); 1198 continue; 1199 } 1200 if (bootverbose) 1201 printf("Preloaded %s \"%s\" at %p.\n", modtype, modname, 1202 modptr); 1203 lf = NULL; 1204 TAILQ_FOREACH(lc, &classes, link) { 1205 error = LINKER_LINK_PRELOAD(lc, modname, &lf); 1206 if (!error) 1207 break; 1208 lf = NULL; 1209 } 1210 if (lf) 1211 TAILQ_INSERT_TAIL(&loaded_files, lf, loaded); 1212 } 1213 1214 /* 1215 * First get a list of stuff in the kernel. 1216 */ 1217 if (linker_file_lookup_set(linker_kernel_file, MDT_SETNAME, &start, 1218 &stop, NULL) == 0) 1219 linker_addmodules(linker_kernel_file, start, stop, 1); 1220 1221 /* 1222 * this is a once-off kinky bubble sort resolve relocation dependency 1223 * requirements 1224 */ 1225 restart: 1226 TAILQ_FOREACH(lf, &loaded_files, loaded) { 1227 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1228 &stop, NULL); 1229 /* 1230 * First, look to see if we would successfully link with this 1231 * stuff. 1232 */ 1233 resolves = 1; /* unless we know otherwise */ 1234 if (!error) { 1235 for (mdp = start; mdp < stop; mdp++) { 1236 mp = *mdp; 1237 if (mp->md_type != MDT_DEPEND) 1238 continue; 1239 modname = mp->md_cval; 1240 verinfo = mp->md_data; 1241 for (nmdp = start; nmdp < stop; nmdp++) { 1242 nmp = *nmdp; 1243 if (nmp->md_type != MDT_VERSION) 1244 continue; 1245 nmodname = nmp->md_cval; 1246 if (strcmp(modname, nmodname) == 0) 1247 break; 1248 } 1249 if (nmdp < stop) /* it's a self reference */ 1250 continue; 1251 1252 /* 1253 * ok, the module isn't here yet, we 1254 * are not finished 1255 */ 1256 if (modlist_lookup2(modname, verinfo) == NULL) 1257 resolves = 0; 1258 } 1259 } 1260 /* 1261 * OK, if we found our modules, we can link. So, "provide" 1262 * the modules inside and add it to the end of the link order 1263 * list. 1264 */ 1265 if (resolves) { 1266 if (!error) { 1267 for (mdp = start; mdp < stop; mdp++) { 1268 mp = *mdp; 1269 if (mp->md_type != MDT_VERSION) 1270 continue; 1271 modname = mp->md_cval; 1272 nver = ((struct mod_version *) 1273 mp->md_data)->mv_version; 1274 if (modlist_lookup(modname, 1275 nver) != NULL) { 1276 printf("module %s already" 1277 " present!\n", modname); 1278 linker_file_unload(lf, 1279 LINKER_UNLOAD_FORCE); 1280 TAILQ_REMOVE(&loaded_files, 1281 lf, loaded); 1282 /* we changed tailq next ptr */ 1283 goto restart; 1284 } 1285 modlist_newmodule(modname, nver, lf); 1286 } 1287 } 1288 TAILQ_REMOVE(&loaded_files, lf, loaded); 1289 TAILQ_INSERT_TAIL(&depended_files, lf, loaded); 1290 /* 1291 * Since we provided modules, we need to restart the 1292 * sort so that the previous files that depend on us 1293 * have a chance. Also, we've busted the tailq next 1294 * pointer with the REMOVE. 1295 */ 1296 goto restart; 1297 } 1298 } 1299 1300 /* 1301 * At this point, we check to see what could not be resolved.. 1302 */ 1303 TAILQ_FOREACH(lf, &loaded_files, loaded) { 1304 printf("KLD file %s is missing dependencies\n", lf->filename); 1305 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1306 TAILQ_REMOVE(&loaded_files, lf, loaded); 1307 } 1308 1309 /* 1310 * We made it. Finish off the linking in the order we determined. 1311 */ 1312 TAILQ_FOREACH(lf, &depended_files, loaded) { 1313 if (linker_kernel_file) { 1314 linker_kernel_file->refs++; 1315 error = linker_file_add_dependency(lf, 1316 linker_kernel_file); 1317 if (error) 1318 panic("cannot add dependency"); 1319 } 1320 lf->userrefs++; /* so we can (try to) kldunload it */ 1321 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1322 &stop, NULL); 1323 if (!error) { 1324 for (mdp = start; mdp < stop; mdp++) { 1325 mp = *mdp; 1326 if (mp->md_type != MDT_DEPEND) 1327 continue; 1328 modname = mp->md_cval; 1329 verinfo = mp->md_data; 1330 mod = modlist_lookup2(modname, verinfo); 1331 mod->container->refs++; 1332 error = linker_file_add_dependency(lf, 1333 mod->container); 1334 if (error) 1335 panic("cannot add dependency"); 1336 } 1337 } 1338 /* 1339 * Now do relocation etc using the symbol search paths 1340 * established by the dependencies 1341 */ 1342 error = LINKER_LINK_PRELOAD_FINISH(lf); 1343 if (error) { 1344 printf("KLD file %s - could not finalize loading\n", 1345 lf->filename); 1346 linker_file_unload(lf, LINKER_UNLOAD_FORCE); 1347 continue; 1348 } 1349 linker_file_register_modules(lf); 1350 if (linker_file_lookup_set(lf, "sysinit_set", &si_start, 1351 &si_stop, NULL) == 0) 1352 sysinit_add(si_start, si_stop); 1353 linker_file_register_sysctls(lf); 1354 lf->flags |= LINKER_FILE_LINKED; 1355 } 1356 /* woohoo! we made it! */ 1357 } 1358 1359 SYSINIT(preload, SI_SUB_KLD, SI_ORDER_MIDDLE, linker_preload, 0) 1360 1361 /* 1362 * Search for a not-loaded module by name. 1363 * 1364 * Modules may be found in the following locations: 1365 * 1366 * - preloaded (result is just the module name) - on disk (result is full path 1367 * to module) 1368 * 1369 * If the module name is qualified in any way (contains path, etc.) the we 1370 * simply return a copy of it. 1371 * 1372 * The search path can be manipulated via sysctl. Note that we use the ';' 1373 * character as a separator to be consistent with the bootloader. 1374 */ 1375 1376 static char linker_hintfile[] = "linker.hints"; 1377 static char linker_path[MAXPATHLEN] = "/boot/kernel;/boot/modules"; 1378 1379 SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RW, linker_path, 1380 sizeof(linker_path), "module load search path"); 1381 1382 TUNABLE_STR("module_path", linker_path, sizeof(linker_path)); 1383 1384 static char *linker_ext_list[] = { 1385 "", 1386 ".ko", 1387 NULL 1388 }; 1389 1390 /* 1391 * Check if file actually exists either with or without extension listed in 1392 * the linker_ext_list. (probably should be generic for the rest of the 1393 * kernel) 1394 */ 1395 static char * 1396 linker_lookup_file(const char *path, int pathlen, const char *name, 1397 int namelen, struct vattr *vap) 1398 { 1399 struct nameidata nd; 1400 struct thread *td = curthread; /* XXX */ 1401 char *result, **cpp, *sep; 1402 int error, len, extlen, reclen, flags; 1403 enum vtype type; 1404 1405 extlen = 0; 1406 for (cpp = linker_ext_list; *cpp; cpp++) { 1407 len = strlen(*cpp); 1408 if (len > extlen) 1409 extlen = len; 1410 } 1411 extlen++; /* trailing '\0' */ 1412 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1413 1414 reclen = pathlen + strlen(sep) + namelen + extlen + 1; 1415 result = malloc(reclen, M_LINKER, M_WAITOK); 1416 for (cpp = linker_ext_list; *cpp; cpp++) { 1417 snprintf(result, reclen, "%.*s%s%.*s%s", pathlen, path, sep, 1418 namelen, name, *cpp); 1419 /* 1420 * Attempt to open the file, and return the path if 1421 * we succeed and it's a regular file. 1422 */ 1423 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, result, td); 1424 flags = FREAD; 1425 error = vn_open(&nd, &flags, 0, -1); 1426 if (error == 0) { 1427 NDFREE(&nd, NDF_ONLY_PNBUF); 1428 type = nd.ni_vp->v_type; 1429 if (vap) 1430 VOP_GETATTR(nd.ni_vp, vap, td->td_ucred, td); 1431 VOP_UNLOCK(nd.ni_vp, 0, td); 1432 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 1433 if (type == VREG) 1434 return (result); 1435 } 1436 } 1437 free(result, M_LINKER); 1438 return (NULL); 1439 } 1440 1441 #define INT_ALIGN(base, ptr) ptr = \ 1442 (base) + (((ptr) - (base) + sizeof(int) - 1) & ~(sizeof(int) - 1)) 1443 1444 /* 1445 * Lookup KLD which contains requested module in the "linker.hints" file. If 1446 * version specification is available, then try to find the best KLD. 1447 * Otherwise just find the latest one. 1448 */ 1449 static char * 1450 linker_hints_lookup(const char *path, int pathlen, const char *modname, 1451 int modnamelen, struct mod_depend *verinfo) 1452 { 1453 struct thread *td = curthread; /* XXX */ 1454 struct ucred *cred = td ? td->td_ucred : NULL; 1455 struct nameidata nd; 1456 struct vattr vattr, mattr; 1457 u_char *hints = NULL; 1458 u_char *cp, *recptr, *bufend, *result, *best, *pathbuf, *sep; 1459 int error, ival, bestver, *intp, reclen, found, flags, clen, blen; 1460 1461 result = NULL; 1462 bestver = found = 0; 1463 1464 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1465 reclen = imax(modnamelen, strlen(linker_hintfile)) + pathlen + 1466 strlen(sep) + 1; 1467 pathbuf = malloc(reclen, M_LINKER, M_WAITOK); 1468 snprintf(pathbuf, reclen, "%.*s%s%s", pathlen, path, sep, 1469 linker_hintfile); 1470 1471 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, pathbuf, td); 1472 flags = FREAD; 1473 error = vn_open(&nd, &flags, 0, -1); 1474 if (error) 1475 goto bad; 1476 NDFREE(&nd, NDF_ONLY_PNBUF); 1477 if (nd.ni_vp->v_type != VREG) 1478 goto bad; 1479 best = cp = NULL; 1480 error = VOP_GETATTR(nd.ni_vp, &vattr, cred, td); 1481 if (error) 1482 goto bad; 1483 /* 1484 * XXX: we need to limit this number to some reasonable value 1485 */ 1486 if (vattr.va_size > 100 * 1024) { 1487 printf("hints file too large %ld\n", (long)vattr.va_size); 1488 goto bad; 1489 } 1490 hints = malloc(vattr.va_size, M_TEMP, M_WAITOK); 1491 if (hints == NULL) 1492 goto bad; 1493 error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)hints, vattr.va_size, 0, 1494 UIO_SYSSPACE, IO_NODELOCKED, cred, NOCRED, &reclen, td); 1495 if (error) 1496 goto bad; 1497 VOP_UNLOCK(nd.ni_vp, 0, td); 1498 vn_close(nd.ni_vp, FREAD, cred, td); 1499 nd.ni_vp = NULL; 1500 if (reclen != 0) { 1501 printf("can't read %d\n", reclen); 1502 goto bad; 1503 } 1504 intp = (int *)hints; 1505 ival = *intp++; 1506 if (ival != LINKER_HINTS_VERSION) { 1507 printf("hints file version mismatch %d\n", ival); 1508 goto bad; 1509 } 1510 bufend = hints + vattr.va_size; 1511 recptr = (u_char *)intp; 1512 clen = blen = 0; 1513 while (recptr < bufend && !found) { 1514 intp = (int *)recptr; 1515 reclen = *intp++; 1516 ival = *intp++; 1517 cp = (char *)intp; 1518 switch (ival) { 1519 case MDT_VERSION: 1520 clen = *cp++; 1521 if (clen != modnamelen || bcmp(cp, modname, clen) != 0) 1522 break; 1523 cp += clen; 1524 INT_ALIGN(hints, cp); 1525 ival = *(int *)cp; 1526 cp += sizeof(int); 1527 clen = *cp++; 1528 if (verinfo == NULL || 1529 ival == verinfo->md_ver_preferred) { 1530 found = 1; 1531 break; 1532 } 1533 if (ival >= verinfo->md_ver_minimum && 1534 ival <= verinfo->md_ver_maximum && 1535 ival > bestver) { 1536 bestver = ival; 1537 best = cp; 1538 blen = clen; 1539 } 1540 break; 1541 default: 1542 break; 1543 } 1544 recptr += reclen + sizeof(int); 1545 } 1546 /* 1547 * Finally check if KLD is in the place 1548 */ 1549 if (found) 1550 result = linker_lookup_file(path, pathlen, cp, clen, &mattr); 1551 else if (best) 1552 result = linker_lookup_file(path, pathlen, best, blen, &mattr); 1553 1554 /* 1555 * KLD is newer than hints file. What we should do now? 1556 */ 1557 if (result && timespeccmp(&mattr.va_mtime, &vattr.va_mtime, >)) 1558 printf("warning: KLD '%s' is newer than the linker.hints" 1559 " file\n", result); 1560 bad: 1561 free(pathbuf, M_LINKER); 1562 if (hints) 1563 free(hints, M_TEMP); 1564 if (nd.ni_vp != NULL) { 1565 VOP_UNLOCK(nd.ni_vp, 0, td); 1566 vn_close(nd.ni_vp, FREAD, cred, td); 1567 } 1568 /* 1569 * If nothing found or hints is absent - fallback to the old 1570 * way by using "kldname[.ko]" as module name. 1571 */ 1572 if (!found && !bestver && result == NULL) 1573 result = linker_lookup_file(path, pathlen, modname, 1574 modnamelen, NULL); 1575 return (result); 1576 } 1577 1578 /* 1579 * Lookup KLD which contains requested module in the all directories. 1580 */ 1581 static char * 1582 linker_search_module(const char *modname, int modnamelen, 1583 struct mod_depend *verinfo) 1584 { 1585 char *cp, *ep, *result; 1586 1587 /* 1588 * traverse the linker path 1589 */ 1590 for (cp = linker_path; *cp; cp = ep + 1) { 1591 /* find the end of this component */ 1592 for (ep = cp; (*ep != 0) && (*ep != ';'); ep++); 1593 result = linker_hints_lookup(cp, ep - cp, modname, 1594 modnamelen, verinfo); 1595 if (result != NULL) 1596 return (result); 1597 if (*ep == 0) 1598 break; 1599 } 1600 return (NULL); 1601 } 1602 1603 /* 1604 * Search for module in all directories listed in the linker_path. 1605 */ 1606 static char * 1607 linker_search_kld(const char *name) 1608 { 1609 char *cp, *ep, *result, **cpp; 1610 int extlen, len; 1611 1612 /* qualified at all? */ 1613 if (index(name, '/')) 1614 return (linker_strdup(name)); 1615 1616 extlen = 0; 1617 for (cpp = linker_ext_list; *cpp; cpp++) { 1618 len = strlen(*cpp); 1619 if (len > extlen) 1620 extlen = len; 1621 } 1622 extlen++; /* trailing '\0' */ 1623 1624 /* traverse the linker path */ 1625 len = strlen(name); 1626 for (ep = linker_path; *ep; ep++) { 1627 cp = ep; 1628 /* find the end of this component */ 1629 for (; *ep != 0 && *ep != ';'; ep++); 1630 result = linker_lookup_file(cp, ep - cp, name, len, NULL); 1631 if (result != NULL) 1632 return (result); 1633 } 1634 return (NULL); 1635 } 1636 1637 static const char * 1638 linker_basename(const char *path) 1639 { 1640 const char *filename; 1641 1642 filename = rindex(path, '/'); 1643 if (filename == NULL) 1644 return path; 1645 if (filename[1]) 1646 filename++; 1647 return (filename); 1648 } 1649 1650 /* 1651 * Find a file which contains given module and load it, if "parent" is not 1652 * NULL, register a reference to it. 1653 */ 1654 int 1655 linker_load_module(const char *kldname, const char *modname, 1656 struct linker_file *parent, struct mod_depend *verinfo, 1657 struct linker_file **lfpp) 1658 { 1659 linker_file_t lfdep; 1660 const char *filename; 1661 char *pathname; 1662 int error; 1663 1664 if (modname == NULL) { 1665 /* 1666 * We have to load KLD 1667 */ 1668 KASSERT(verinfo == NULL, ("linker_load_module: verinfo" 1669 " is not NULL")); 1670 pathname = linker_search_kld(kldname); 1671 } else { 1672 if (modlist_lookup2(modname, verinfo) != NULL) 1673 return (EEXIST); 1674 if (kldname != NULL) 1675 pathname = linker_strdup(kldname); 1676 else if (rootvnode == NULL) 1677 pathname = NULL; 1678 else 1679 /* 1680 * Need to find a KLD with required module 1681 */ 1682 pathname = linker_search_module(modname, 1683 strlen(modname), verinfo); 1684 } 1685 if (pathname == NULL) 1686 return (ENOENT); 1687 1688 /* 1689 * Can't load more than one file with the same basename XXX: 1690 * Actually it should be possible to have multiple KLDs with 1691 * the same basename but different path because they can 1692 * provide different versions of the same modules. 1693 */ 1694 filename = linker_basename(pathname); 1695 if (linker_find_file_by_name(filename)) { 1696 error = EEXIST; 1697 goto out; 1698 } 1699 do { 1700 error = linker_load_file(pathname, &lfdep); 1701 if (error) 1702 break; 1703 if (modname && verinfo && 1704 modlist_lookup2(modname, verinfo) == NULL) { 1705 linker_file_unload(lfdep, LINKER_UNLOAD_FORCE); 1706 error = ENOENT; 1707 break; 1708 } 1709 if (parent) { 1710 error = linker_file_add_dependency(parent, lfdep); 1711 if (error) 1712 break; 1713 } 1714 if (lfpp) 1715 *lfpp = lfdep; 1716 } while (0); 1717 out: 1718 if (pathname) 1719 free(pathname, M_LINKER); 1720 return (error); 1721 } 1722 1723 /* 1724 * This routine is responsible for finding dependencies of userland initiated 1725 * kldload(2)'s of files. 1726 */ 1727 int 1728 linker_load_dependencies(linker_file_t lf) 1729 { 1730 linker_file_t lfdep; 1731 struct mod_metadata **start, **stop, **mdp, **nmdp; 1732 struct mod_metadata *mp, *nmp; 1733 struct mod_depend *verinfo; 1734 modlist_t mod; 1735 const char *modname, *nmodname; 1736 int ver, error = 0, count; 1737 1738 /* 1739 * All files are dependant on /kernel. 1740 */ 1741 if (linker_kernel_file) { 1742 linker_kernel_file->refs++; 1743 error = linker_file_add_dependency(lf, linker_kernel_file); 1744 if (error) 1745 return (error); 1746 } 1747 if (linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop, 1748 &count) != 0) 1749 return (0); 1750 for (mdp = start; mdp < stop; mdp++) { 1751 mp = *mdp; 1752 if (mp->md_type != MDT_VERSION) 1753 continue; 1754 modname = mp->md_cval; 1755 ver = ((struct mod_version *)mp->md_data)->mv_version; 1756 mod = modlist_lookup(modname, ver); 1757 if (mod != NULL) { 1758 printf("interface %s.%d already present in the KLD" 1759 " '%s'!\n", modname, ver, 1760 mod->container->filename); 1761 return (EEXIST); 1762 } 1763 } 1764 1765 for (mdp = start; mdp < stop; mdp++) { 1766 mp = *mdp; 1767 if (mp->md_type != MDT_DEPEND) 1768 continue; 1769 modname = mp->md_cval; 1770 verinfo = mp->md_data; 1771 nmodname = NULL; 1772 for (nmdp = start; nmdp < stop; nmdp++) { 1773 nmp = *nmdp; 1774 if (nmp->md_type != MDT_VERSION) 1775 continue; 1776 nmodname = nmp->md_cval; 1777 if (strcmp(modname, nmodname) == 0) 1778 break; 1779 } 1780 if (nmdp < stop)/* early exit, it's a self reference */ 1781 continue; 1782 mod = modlist_lookup2(modname, verinfo); 1783 if (mod) { /* woohoo, it's loaded already */ 1784 lfdep = mod->container; 1785 lfdep->refs++; 1786 error = linker_file_add_dependency(lf, lfdep); 1787 if (error) 1788 break; 1789 continue; 1790 } 1791 error = linker_load_module(NULL, modname, lf, verinfo, NULL); 1792 if (error) { 1793 printf("KLD %s: depends on %s - not available\n", 1794 lf->filename, modname); 1795 break; 1796 } 1797 } 1798 1799 if (error) 1800 return (error); 1801 linker_addmodules(lf, start, stop, 0); 1802 return (error); 1803 } 1804 1805 static int 1806 sysctl_kern_function_list_iterate(const char *name, void *opaque) 1807 { 1808 struct sysctl_req *req; 1809 1810 req = opaque; 1811 return (SYSCTL_OUT(req, name, strlen(name) + 1)); 1812 } 1813 1814 /* 1815 * Export a nul-separated, double-nul-terminated list of all function names 1816 * in the kernel. 1817 */ 1818 static int 1819 sysctl_kern_function_list(SYSCTL_HANDLER_ARGS) 1820 { 1821 linker_file_t lf; 1822 int error; 1823 1824 #ifdef MAC 1825 error = mac_check_kld_stat(req->td->td_ucred); 1826 if (error) 1827 return (error); 1828 #endif 1829 error = sysctl_wire_old_buffer(req, 0); 1830 if (error != 0) 1831 return (error); 1832 mtx_lock(&kld_mtx); 1833 TAILQ_FOREACH(lf, &linker_files, link) { 1834 error = LINKER_EACH_FUNCTION_NAME(lf, 1835 sysctl_kern_function_list_iterate, req); 1836 if (error) { 1837 mtx_unlock(&kld_mtx); 1838 return (error); 1839 } 1840 } 1841 mtx_unlock(&kld_mtx); 1842 return (SYSCTL_OUT(req, "", 1)); 1843 } 1844 1845 SYSCTL_PROC(_kern, OID_AUTO, function_list, CTLFLAG_RD, 1846 NULL, 0, sysctl_kern_function_list, "", "kernel function list");
Cache object: 123b9a3f272af3d021ef68c1324efc78
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