kern_linker.c revision 92032
1/*- 2 * Copyright (c) 1997-2000 Doug Rabson 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $FreeBSD: head/sys/kern/kern_linker.c 92032 2002-03-10 23:12:43Z dwmalone $ 27 */ 28 29#include "opt_ddb.h" 30 31#include <sys/param.h> 32#include <sys/kernel.h> 33#include <sys/systm.h> 34#include <sys/malloc.h> 35#include <sys/sysproto.h> 36#include <sys/sysent.h> 37#include <sys/proc.h> 38#include <sys/lock.h> 39#include <sys/mutex.h> 40#include <sys/module.h> 41#include <sys/linker.h> 42#include <sys/fcntl.h> 43#include <sys/libkern.h> 44#include <sys/namei.h> 45#include <sys/vnode.h> 46#include <sys/sysctl.h> 47 48 49#include "linker_if.h" 50 51#ifdef KLD_DEBUG 52int kld_debug = 0; 53#endif 54 55/* 56 * static char *linker_search_path(const char *name, struct mod_depend 57 * *verinfo); 58 */ 59static const char *linker_basename(const char *path); 60static int linker_load_module(const char *kldname, const char *modname, 61 struct linker_file *parent, struct mod_depend *verinfo, 62 struct linker_file **lfpp); 63 64/* Metadata from the static kernel */ 65SET_DECLARE(modmetadata_set, struct mod_metadata); 66 67MALLOC_DEFINE(M_LINKER, "linker", "kernel linker"); 68 69linker_file_t linker_kernel_file; 70 71static struct lock lock; /* lock for the file list */ 72static linker_class_list_t classes; 73static linker_file_list_t linker_files; 74static int next_file_id = 1; 75 76#define LINKER_GET_NEXT_FILE_ID(a) do { \ 77 linker_file_t lftmp; \ 78 \ 79retry: \ 80 TAILQ_FOREACH(lftmp, &linker_files, link) { \ 81 if (next_file_id == lftmp->id) { \ 82 next_file_id++; \ 83 goto retry; \ 84 } \ 85 } \ 86 (a) = next_file_id; \ 87} while(0) 88 89 90/* XXX wrong name; we're looking at version provision tags here, not modules */ 91typedef TAILQ_HEAD(, modlist) modlisthead_t; 92struct modlist { 93 TAILQ_ENTRY(modlist) link; /* chain together all modules */ 94 linker_file_t container; 95 const char *name; 96 int version; 97}; 98typedef struct modlist *modlist_t; 99static modlisthead_t found_modules; 100 101static char * 102linker_strdup(const char *str) 103{ 104 char *result; 105 106 if ((result = malloc((strlen(str) + 1), M_LINKER, M_WAITOK)) != NULL) 107 strcpy(result, str); 108 return (result); 109} 110 111static void 112linker_init(void *arg) 113{ 114 115 lockinit(&lock, PVM, "klink", 0, 0); 116 TAILQ_INIT(&classes); 117 TAILQ_INIT(&linker_files); 118} 119 120SYSINIT(linker, SI_SUB_KLD, SI_ORDER_FIRST, linker_init, 0) 121 122int 123linker_add_class(linker_class_t lc) 124{ 125 126 kobj_class_compile((kobj_class_t) lc); 127 TAILQ_INSERT_TAIL(&classes, lc, link); 128 return (0); 129} 130 131static void 132linker_file_sysinit(linker_file_t lf) 133{ 134 struct sysinit **start, **stop, **sipp, **xipp, *save; 135 136 KLD_DPF(FILE, ("linker_file_sysinit: calling SYSINITs for %s\n", 137 lf->filename)); 138 139 if (linker_file_lookup_set(lf, "sysinit_set", &start, &stop, NULL) != 0) 140 return; 141 /* 142 * Perform a bubble sort of the system initialization objects by 143 * their subsystem (primary key) and order (secondary key). 144 * 145 * Since some things care about execution order, this is the operation 146 * which ensures continued function. 147 */ 148 for (sipp = start; sipp < stop; sipp++) { 149 for (xipp = sipp + 1; xipp < stop; xipp++) { 150 if ((*sipp)->subsystem < (*xipp)->subsystem || 151 ((*sipp)->subsystem == (*xipp)->subsystem && 152 (*sipp)->order <= (*xipp)->order)) 153 continue; /* skip */ 154 save = *sipp; 155 *sipp = *xipp; 156 *xipp = save; 157 } 158 } 159 160 /* 161 * Traverse the (now) ordered list of system initialization tasks. 162 * Perform each task, and continue on to the next task. 163 */ 164 for (sipp = start; sipp < stop; sipp++) { 165 if ((*sipp)->subsystem == SI_SUB_DUMMY) 166 continue; /* skip dummy task(s) */ 167 168 /* Call function */ 169 (*((*sipp)->func)) ((*sipp)->udata); 170 } 171} 172 173static void 174linker_file_sysuninit(linker_file_t lf) 175{ 176 struct sysinit **start, **stop, **sipp, **xipp, *save; 177 178 KLD_DPF(FILE, ("linker_file_sysuninit: calling SYSUNINITs for %s\n", 179 lf->filename)); 180 181 if (linker_file_lookup_set(lf, "sysuninit_set", &start, &stop, 182 NULL) != 0) 183 return; 184 185 /* 186 * Perform a reverse bubble sort of the system initialization objects 187 * by their subsystem (primary key) and order (secondary key). 188 * 189 * Since some things care about execution order, this is the operation 190 * which ensures continued function. 191 */ 192 for (sipp = start; sipp < stop; sipp++) { 193 for (xipp = sipp + 1; xipp < stop; xipp++) { 194 if ((*sipp)->subsystem > (*xipp)->subsystem || 195 ((*sipp)->subsystem == (*xipp)->subsystem && 196 (*sipp)->order >= (*xipp)->order)) 197 continue; /* skip */ 198 save = *sipp; 199 *sipp = *xipp; 200 *xipp = save; 201 } 202 } 203 204 /* 205 * Traverse the (now) ordered list of system initialization tasks. 206 * Perform each task, and continue on to the next task. 207 */ 208 for (sipp = start; sipp < stop; sipp++) { 209 if ((*sipp)->subsystem == SI_SUB_DUMMY) 210 continue; /* skip dummy task(s) */ 211 212 /* Call function */ 213 (*((*sipp)->func)) ((*sipp)->udata); 214 } 215} 216 217static void 218linker_file_register_sysctls(linker_file_t lf) 219{ 220 struct sysctl_oid **start, **stop, **oidp; 221 222 KLD_DPF(FILE, 223 ("linker_file_register_sysctls: registering SYSCTLs for %s\n", 224 lf->filename)); 225 226 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0) 227 return; 228 229 for (oidp = start; oidp < stop; oidp++) 230 sysctl_register_oid(*oidp); 231} 232 233static void 234linker_file_unregister_sysctls(linker_file_t lf) 235{ 236 struct sysctl_oid **start, **stop, **oidp; 237 238 KLD_DPF(FILE, ("linker_file_unregister_sysctls: registering SYSCTLs" 239 " for %s\n", lf->filename)); 240 241 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0) 242 return; 243 244 for (oidp = start; oidp < stop; oidp++) 245 sysctl_unregister_oid(*oidp); 246} 247 248static int 249linker_file_register_modules(linker_file_t lf) 250{ 251 struct mod_metadata **start, **stop, **mdp; 252 const moduledata_t *moddata; 253 int error; 254 255 KLD_DPF(FILE, ("linker_file_register_modules: registering modules" 256 " in %s\n", lf->filename)); 257 258 if (linker_file_lookup_set(lf, "modmetadata_set", &start, 259 &stop, 0) != 0) { 260 /* 261 * This fallback should be unnecessary, but if we get booted 262 * from boot2 instead of loader and we are missing our 263 * metadata then we have to try the best we can. 264 */ 265 if (lf == linker_kernel_file) { 266 start = SET_BEGIN(modmetadata_set); 267 stop = SET_LIMIT(modmetadata_set); 268 } else 269 return (0); 270 } 271 for (mdp = start; mdp < stop; mdp++) { 272 if ((*mdp)->md_type != MDT_MODULE) 273 continue; 274 moddata = (*mdp)->md_data; 275 KLD_DPF(FILE, ("Registering module %s in %s\n", 276 moddata->name, lf->filename)); 277 if (module_lookupbyname(moddata->name) != NULL) { 278 printf("Warning: module %s already exists\n", 279 moddata->name); 280 continue; /* or return a error ? */ 281 } 282 error = module_register(moddata, lf); 283 if (error) 284 printf("Module %s failed to register: %d\n", 285 moddata->name, error); 286 } 287 return (0); 288} 289 290static void 291linker_init_kernel_modules(void) 292{ 293 294 linker_file_register_modules(linker_kernel_file); 295} 296 297SYSINIT(linker_kernel, SI_SUB_KLD, SI_ORDER_ANY, linker_init_kernel_modules, 0) 298 299int 300linker_load_file(const char *filename, linker_file_t *result) 301{ 302 linker_class_t lc; 303 linker_file_t lf; 304 int foundfile, error = 0; 305 306 /* Refuse to load modules if securelevel raised */ 307 if (securelevel > 0) 308 return (EPERM); 309 310 lf = linker_find_file_by_name(filename); 311 if (lf) { 312 KLD_DPF(FILE, ("linker_load_file: file %s is already loaded," 313 " incrementing refs\n", filename)); 314 *result = lf; 315 lf->refs++; 316 goto out; 317 } 318 lf = NULL; 319 foundfile = 0; 320 TAILQ_FOREACH(lc, &classes, link) { 321 KLD_DPF(FILE, ("linker_load_file: trying to load %s\n", 322 filename)); 323 error = LINKER_LOAD_FILE(lc, filename, &lf); 324 /* 325 * If we got something other than ENOENT, then it exists but 326 * we cannot load it for some other reason. 327 */ 328 if (error != ENOENT) 329 foundfile = 1; 330 if (lf) { 331 linker_file_register_modules(lf); 332 linker_file_register_sysctls(lf); 333 linker_file_sysinit(lf); 334 lf->flags |= LINKER_FILE_LINKED; 335 *result = lf; 336 error = 0; 337 goto out; 338 } 339 } 340 /* 341 * Less than ideal, but tells the user whether it failed to load or 342 * the module was not found. 343 */ 344 if (foundfile) 345 /* Format not recognized (or unloadable). */ 346 error = ENOEXEC; 347 else 348 error = ENOENT; /* Nothing found */ 349out: 350 return (error); 351} 352 353/* XXX: function parameters are incomplete */ 354int 355linker_reference_module(const char *modname, linker_file_t *result) 356{ 357 return (linker_load_module(NULL, modname, NULL, NULL, result)); 358} 359 360linker_file_t 361linker_find_file_by_name(const char *filename) 362{ 363 linker_file_t lf = 0; 364 char *koname; 365 366 koname = malloc(strlen(filename) + 4, M_LINKER, M_WAITOK); 367 if (koname == NULL) 368 goto out; 369 sprintf(koname, "%s.ko", filename); 370 371 lockmgr(&lock, LK_SHARED, 0, curthread); 372 TAILQ_FOREACH(lf, &linker_files, link) { 373 if (strcmp(lf->filename, koname) == 0) 374 break; 375 if (strcmp(lf->filename, filename) == 0) 376 break; 377 } 378 lockmgr(&lock, LK_RELEASE, 0, curthread); 379out: 380 if (koname) 381 free(koname, M_LINKER); 382 return (lf); 383} 384 385linker_file_t 386linker_find_file_by_id(int fileid) 387{ 388 linker_file_t lf = 0; 389 390 lockmgr(&lock, LK_SHARED, 0, curthread); 391 TAILQ_FOREACH(lf, &linker_files, link) 392 if (lf->id == fileid) 393 break; 394 lockmgr(&lock, LK_RELEASE, 0, curthread); 395 return (lf); 396} 397 398linker_file_t 399linker_make_file(const char *pathname, linker_class_t lc) 400{ 401 linker_file_t lf; 402 const char *filename; 403 404 lf = NULL; 405 filename = linker_basename(pathname); 406 407 KLD_DPF(FILE, ("linker_make_file: new file, filename=%s\n", filename)); 408 lockmgr(&lock, LK_EXCLUSIVE, 0, curthread); 409 lf = (linker_file_t)kobj_create((kobj_class_t)lc, M_LINKER, M_WAITOK); 410 if (lf == NULL) 411 goto out; 412 lf->refs = 1; 413 lf->userrefs = 0; 414 lf->flags = 0; 415 lf->filename = linker_strdup(filename); 416 LINKER_GET_NEXT_FILE_ID(lf->id); 417 lf->ndeps = 0; 418 lf->deps = NULL; 419 STAILQ_INIT(&lf->common); 420 TAILQ_INIT(&lf->modules); 421 TAILQ_INSERT_TAIL(&linker_files, lf, link); 422out: 423 lockmgr(&lock, LK_RELEASE, 0, curthread); 424 return (lf); 425} 426 427int 428linker_file_unload(linker_file_t file) 429{ 430 module_t mod, next; 431 modlist_t ml, nextml; 432 struct common_symbol *cp; 433 int error, i; 434 435 error = 0; 436 437 /* Refuse to unload modules if securelevel raised. */ 438 if (securelevel > 0) 439 return (EPERM); 440 441 KLD_DPF(FILE, ("linker_file_unload: lf->refs=%d\n", file->refs)); 442 lockmgr(&lock, LK_EXCLUSIVE, 0, curthread); 443 if (file->refs == 1) { 444 KLD_DPF(FILE, ("linker_file_unload: file is unloading," 445 " informing modules\n")); 446 447 /* 448 * Inform any modules associated with this file. 449 */ 450 for (mod = TAILQ_FIRST(&file->modules); mod; mod = next) { 451 next = module_getfnext(mod); 452 453 /* 454 * Give the module a chance to veto the unload. 455 */ 456 if ((error = module_unload(mod)) != 0) { 457 KLD_DPF(FILE, ("linker_file_unload: module %x" 458 " vetoes unload\n", mod)); 459 lockmgr(&lock, LK_RELEASE, 0, curthread); 460 goto out; 461 } 462 module_release(mod); 463 } 464 } 465 file->refs--; 466 if (file->refs > 0) { 467 lockmgr(&lock, LK_RELEASE, 0, curthread); 468 goto out; 469 } 470 for (ml = TAILQ_FIRST(&found_modules); ml; ml = nextml) { 471 nextml = TAILQ_NEXT(ml, link); 472 if (ml->container == file) 473 TAILQ_REMOVE(&found_modules, ml, link); 474 } 475 476 /* 477 * Don't try to run SYSUNINITs if we are unloaded due to a 478 * link error. 479 */ 480 if (file->flags & LINKER_FILE_LINKED) { 481 linker_file_sysuninit(file); 482 linker_file_unregister_sysctls(file); 483 } 484 TAILQ_REMOVE(&linker_files, file, link); 485 lockmgr(&lock, LK_RELEASE, 0, curthread); 486 487 if (file->deps) { 488 for (i = 0; i < file->ndeps; i++) 489 linker_file_unload(file->deps[i]); 490 free(file->deps, M_LINKER); 491 file->deps = NULL; 492 } 493 for (cp = STAILQ_FIRST(&file->common); cp; 494 cp = STAILQ_FIRST(&file->common)) { 495 STAILQ_REMOVE(&file->common, cp, common_symbol, link); 496 free(cp, M_LINKER); 497 } 498 499 LINKER_UNLOAD(file); 500 if (file->filename) { 501 free(file->filename, M_LINKER); 502 file->filename = NULL; 503 } 504 kobj_delete((kobj_t) file, M_LINKER); 505out: 506 return (error); 507} 508 509int 510linker_file_add_dependency(linker_file_t file, linker_file_t dep) 511{ 512 linker_file_t *newdeps; 513 514 newdeps = malloc((file->ndeps + 1) * sizeof(linker_file_t *), 515 M_LINKER, M_WAITOK | M_ZERO); 516 if (newdeps == NULL) 517 return (ENOMEM); 518 519 if (file->deps) { 520 bcopy(file->deps, newdeps, 521 file->ndeps * sizeof(linker_file_t *)); 522 free(file->deps, M_LINKER); 523 } 524 file->deps = newdeps; 525 file->deps[file->ndeps] = dep; 526 file->ndeps++; 527 return (0); 528} 529 530/* 531 * Locate a linker set and its contents. This is a helper function to avoid 532 * linker_if.h exposure elsewhere. Note: firstp and lastp are really void *** 533 */ 534int 535linker_file_lookup_set(linker_file_t file, const char *name, 536 void *firstp, void *lastp, int *countp) 537{ 538 539 return (LINKER_LOOKUP_SET(file, name, firstp, lastp, countp)); 540} 541 542caddr_t 543linker_file_lookup_symbol(linker_file_t file, const char *name, int deps) 544{ 545 c_linker_sym_t sym; 546 linker_symval_t symval; 547 caddr_t address; 548 size_t common_size = 0; 549 int i; 550 551 KLD_DPF(SYM, ("linker_file_lookup_symbol: file=%x, name=%s, deps=%d\n", 552 file, name, deps)); 553 554 if (LINKER_LOOKUP_SYMBOL(file, name, &sym) == 0) { 555 LINKER_SYMBOL_VALUES(file, sym, &symval); 556 if (symval.value == 0) 557 /* 558 * For commons, first look them up in the 559 * dependencies and only allocate space if not found 560 * there. 561 */ 562 common_size = symval.size; 563 else { 564 KLD_DPF(SYM, ("linker_file_lookup_symbol: symbol" 565 ".value=%x\n", symval.value)); 566 return (symval.value); 567 } 568 } 569 if (deps) { 570 for (i = 0; i < file->ndeps; i++) { 571 address = linker_file_lookup_symbol(file->deps[i], 572 name, 0); 573 if (address) { 574 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 575 " deps value=%x\n", address)); 576 return (address); 577 } 578 } 579 } 580 if (common_size > 0) { 581 /* 582 * This is a common symbol which was not found in the 583 * dependencies. We maintain a simple common symbol table in 584 * the file object. 585 */ 586 struct common_symbol *cp; 587 588 STAILQ_FOREACH(cp, &file->common, link) { 589 if (strcmp(cp->name, name) == 0) { 590 KLD_DPF(SYM, ("linker_file_lookup_symbol:" 591 " old common value=%x\n", cp->address)); 592 return (cp->address); 593 } 594 } 595 /* 596 * Round the symbol size up to align. 597 */ 598 common_size = (common_size + sizeof(int) - 1) & -sizeof(int); 599 cp = malloc(sizeof(struct common_symbol) 600 + common_size + strlen(name) + 1, M_LINKER, 601 M_WAITOK | M_ZERO); 602 if (cp == NULL) { 603 KLD_DPF(SYM, ("linker_file_lookup_symbol: nomem\n")); 604 return (0); 605 } 606 cp->address = (caddr_t)(cp + 1); 607 cp->name = cp->address + common_size; 608 strcpy(cp->name, name); 609 bzero(cp->address, common_size); 610 STAILQ_INSERT_TAIL(&file->common, cp, link); 611 612 KLD_DPF(SYM, ("linker_file_lookup_symbol: new common" 613 " value=%x\n", cp->address)); 614 return (cp->address); 615 } 616 KLD_DPF(SYM, ("linker_file_lookup_symbol: fail\n")); 617 return (0); 618} 619 620#ifdef DDB 621/* 622 * DDB Helpers. DDB has to look across multiple files with their own symbol 623 * tables and string tables. 624 * 625 * Note that we do not obey list locking protocols here. We really don't need 626 * DDB to hang because somebody's got the lock held. We'll take the chance 627 * that the files list is inconsistant instead. 628 */ 629 630int 631linker_ddb_lookup(const char *symstr, c_linker_sym_t *sym) 632{ 633 linker_file_t lf; 634 635 TAILQ_FOREACH(lf, &linker_files, link) { 636 if (LINKER_LOOKUP_SYMBOL(lf, symstr, sym) == 0) 637 return (0); 638 } 639 return (ENOENT); 640} 641 642int 643linker_ddb_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) 644{ 645 linker_file_t lf; 646 c_linker_sym_t best, es; 647 u_long diff, bestdiff, off; 648 649 best = 0; 650 off = (uintptr_t)value; 651 bestdiff = off; 652 TAILQ_FOREACH(lf, &linker_files, link) { 653 if (LINKER_SEARCH_SYMBOL(lf, value, &es, &diff) != 0) 654 continue; 655 if (es != 0 && diff < bestdiff) { 656 best = es; 657 bestdiff = diff; 658 } 659 if (bestdiff == 0) 660 break; 661 } 662 if (best) { 663 *sym = best; 664 *diffp = bestdiff; 665 return (0); 666 } else { 667 *sym = 0; 668 *diffp = off; 669 return (ENOENT); 670 } 671} 672 673int 674linker_ddb_symbol_values(c_linker_sym_t sym, linker_symval_t *symval) 675{ 676 linker_file_t lf; 677 678 TAILQ_FOREACH(lf, &linker_files, link) { 679 if (LINKER_SYMBOL_VALUES(lf, sym, symval) == 0) 680 return (0); 681 } 682 return (ENOENT); 683} 684#endif 685 686/* 687 * Syscalls. 688 */ 689/* 690 * MPSAFE 691 */ 692int 693kldload(struct thread *td, struct kldload_args *uap) 694{ 695 char *kldname, *modname; 696 char *pathname = NULL; 697 linker_file_t lf; 698 int error = 0; 699 700 td->td_retval[0] = -1; 701 702 if (securelevel > 0) /* redundant, but that's OK */ 703 return (EPERM); 704 705 mtx_lock(&Giant); 706 707 if ((error = suser_xxx(td->td_ucred, NULL, 0)) != 0) 708 goto out; 709 710 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 711 if ((error = copyinstr(SCARG(uap, file), pathname, MAXPATHLEN, 712 NULL)) != 0) 713 goto out; 714 715 /* 716 * If path do not contain qualified name or any dot in it 717 * (kldname.ko, or kldname.ver.ko) treat it as interface 718 * name. 719 */ 720 if (index(pathname, '/') || index(pathname, '.')) { 721 kldname = pathname; 722 modname = NULL; 723 } else { 724 kldname = NULL; 725 modname = pathname; 726 } 727 error = linker_load_module(kldname, modname, NULL, NULL, &lf); 728 if (error) 729 goto out; 730 731 lf->userrefs++; 732 td->td_retval[0] = lf->id; 733out: 734 if (pathname) 735 free(pathname, M_TEMP); 736 mtx_unlock(&Giant); 737 return (error); 738} 739 740/* 741 * MPSAFE 742 */ 743int 744kldunload(struct thread *td, struct kldunload_args *uap) 745{ 746 linker_file_t lf; 747 int error = 0; 748 749 if (securelevel > 0) /* redundant, but that's OK */ 750 return (EPERM); 751 752 mtx_lock(&Giant); 753 754 if ((error = suser_xxx(td->td_ucred, NULL, 0)) != 0) 755 goto out; 756 757 lf = linker_find_file_by_id(SCARG(uap, fileid)); 758 if (lf) { 759 KLD_DPF(FILE, ("kldunload: lf->userrefs=%d\n", lf->userrefs)); 760 if (lf->userrefs == 0) { 761 printf("kldunload: attempt to unload file that was" 762 " loaded by the kernel\n"); 763 error = EBUSY; 764 goto out; 765 } 766 lf->userrefs--; 767 error = linker_file_unload(lf); 768 if (error) 769 lf->userrefs++; 770 } else 771 error = ENOENT; 772out: 773 mtx_unlock(&Giant); 774 return (error); 775} 776 777/* 778 * MPSAFE 779 */ 780int 781kldfind(struct thread *td, struct kldfind_args *uap) 782{ 783 char *pathname; 784 const char *filename; 785 linker_file_t lf; 786 int error = 0; 787 788 mtx_lock(&Giant); 789 td->td_retval[0] = -1; 790 791 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 792 if ((error = copyinstr(SCARG(uap, file), pathname, MAXPATHLEN, 793 NULL)) != 0) 794 goto out; 795 796 filename = linker_basename(pathname); 797 lf = linker_find_file_by_name(filename); 798 if (lf) 799 td->td_retval[0] = lf->id; 800 else 801 error = ENOENT; 802out: 803 if (pathname) 804 free(pathname, M_TEMP); 805 mtx_unlock(&Giant); 806 return (error); 807} 808 809/* 810 * MPSAFE 811 */ 812int 813kldnext(struct thread *td, struct kldnext_args *uap) 814{ 815 linker_file_t lf; 816 int error = 0; 817 818 mtx_lock(&Giant); 819 820 if (SCARG(uap, fileid) == 0) { 821 if (TAILQ_FIRST(&linker_files)) 822 td->td_retval[0] = TAILQ_FIRST(&linker_files)->id; 823 else 824 td->td_retval[0] = 0; 825 goto out; 826 } 827 lf = linker_find_file_by_id(SCARG(uap, fileid)); 828 if (lf) { 829 if (TAILQ_NEXT(lf, link)) 830 td->td_retval[0] = TAILQ_NEXT(lf, link)->id; 831 else 832 td->td_retval[0] = 0; 833 } else 834 error = ENOENT; 835out: 836 mtx_unlock(&Giant); 837 return (error); 838} 839 840/* 841 * MPSAFE 842 */ 843int 844kldstat(struct thread *td, struct kldstat_args *uap) 845{ 846 linker_file_t lf; 847 int error = 0; 848 int namelen, version; 849 struct kld_file_stat *stat; 850 851 mtx_lock(&Giant); 852 853 lf = linker_find_file_by_id(SCARG(uap, fileid)); 854 if (lf == NULL) { 855 error = ENOENT; 856 goto out; 857 } 858 stat = SCARG(uap, stat); 859 860 /* 861 * Check the version of the user's structure. 862 */ 863 if ((error = copyin(&stat->version, &version, sizeof(version))) != 0) 864 goto out; 865 if (version != sizeof(struct kld_file_stat)) { 866 error = EINVAL; 867 goto out; 868 } 869 namelen = strlen(lf->filename) + 1; 870 if (namelen > MAXPATHLEN) 871 namelen = MAXPATHLEN; 872 if ((error = copyout(lf->filename, &stat->name[0], namelen)) != 0) 873 goto out; 874 if ((error = copyout(&lf->refs, &stat->refs, sizeof(int))) != 0) 875 goto out; 876 if ((error = copyout(&lf->id, &stat->id, sizeof(int))) != 0) 877 goto out; 878 if ((error = copyout(&lf->address, &stat->address, 879 sizeof(caddr_t))) != 0) 880 goto out; 881 if ((error = copyout(&lf->size, &stat->size, sizeof(size_t))) != 0) 882 goto out; 883 884 td->td_retval[0] = 0; 885out: 886 mtx_unlock(&Giant); 887 return (error); 888} 889 890/* 891 * MPSAFE 892 */ 893int 894kldfirstmod(struct thread *td, struct kldfirstmod_args *uap) 895{ 896 linker_file_t lf; 897 module_t mp; 898 int error = 0; 899 900 mtx_lock(&Giant); 901 lf = linker_find_file_by_id(SCARG(uap, fileid)); 902 if (lf) { 903 mp = TAILQ_FIRST(&lf->modules); 904 if (mp != NULL) 905 td->td_retval[0] = module_getid(mp); 906 else 907 td->td_retval[0] = 0; 908 } else 909 error = ENOENT; 910 mtx_unlock(&Giant); 911 return (error); 912} 913 914/* 915 * MPSAFE 916 */ 917int 918kldsym(struct thread *td, struct kldsym_args *uap) 919{ 920 char *symstr = NULL; 921 c_linker_sym_t sym; 922 linker_symval_t symval; 923 linker_file_t lf; 924 struct kld_sym_lookup lookup; 925 int error = 0; 926 927 mtx_lock(&Giant); 928 929 if ((error = copyin(SCARG(uap, data), &lookup, sizeof(lookup))) != 0) 930 goto out; 931 if (lookup.version != sizeof(lookup) || 932 SCARG(uap, cmd) != KLDSYM_LOOKUP) { 933 error = EINVAL; 934 goto out; 935 } 936 symstr = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 937 if ((error = copyinstr(lookup.symname, symstr, MAXPATHLEN, NULL)) != 0) 938 goto out; 939 if (SCARG(uap, fileid) != 0) { 940 lf = linker_find_file_by_id(SCARG(uap, fileid)); 941 if (lf == NULL) { 942 error = ENOENT; 943 goto out; 944 } 945 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 946 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 947 lookup.symvalue = (uintptr_t) symval.value; 948 lookup.symsize = symval.size; 949 error = copyout(&lookup, SCARG(uap, data), 950 sizeof(lookup)); 951 } else 952 error = ENOENT; 953 } else { 954 TAILQ_FOREACH(lf, &linker_files, link) { 955 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 956 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 957 lookup.symvalue = (uintptr_t)symval.value; 958 lookup.symsize = symval.size; 959 error = copyout(&lookup, SCARG(uap, data), 960 sizeof(lookup)); 961 break; 962 } 963 } 964 if (lf == NULL) 965 error = ENOENT; 966 } 967out: 968 if (symstr) 969 free(symstr, M_TEMP); 970 mtx_unlock(&Giant); 971 return (error); 972} 973 974/* 975 * Preloaded module support 976 */ 977 978static modlist_t 979modlist_lookup(const char *name, int ver) 980{ 981 modlist_t mod; 982 983 TAILQ_FOREACH(mod, &found_modules, link) { 984 if (strcmp(mod->name, name) == 0 && 985 (ver == 0 || mod->version == ver)) 986 return (mod); 987 } 988 return (NULL); 989} 990 991static modlist_t 992modlist_lookup2(const char *name, struct mod_depend *verinfo) 993{ 994 modlist_t mod, bestmod; 995 int ver; 996 997 if (verinfo == NULL) 998 return (modlist_lookup(name, 0)); 999 bestmod = NULL; 1000 for (mod = TAILQ_FIRST(&found_modules); mod; 1001 mod = TAILQ_NEXT(mod, link)) { 1002 if (strcmp(mod->name, name) != 0) 1003 continue; 1004 ver = mod->version; 1005 if (ver == verinfo->md_ver_preferred) 1006 return (mod); 1007 if (ver >= verinfo->md_ver_minimum && 1008 ver <= verinfo->md_ver_maximum && 1009 ver > bestmod->version) 1010 bestmod = mod; 1011 } 1012 return (bestmod); 1013} 1014 1015static modlist_t 1016modlist_newmodule(const char *modname, int version, linker_file_t container) 1017{ 1018 modlist_t mod; 1019 1020 mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT); 1021 if (mod == NULL) 1022 panic("no memory for module list"); 1023 bzero(mod, sizeof(*mod)); 1024 mod->container = container; 1025 mod->name = modname; 1026 mod->version = version; 1027 TAILQ_INSERT_TAIL(&found_modules, mod, link); 1028 return (mod); 1029} 1030 1031/* 1032 * This routine is cheap and nasty but will work for data pointers. 1033 */ 1034static void * 1035linker_reloc_ptr(linker_file_t lf, const void *offset) 1036{ 1037 return (lf->address + (uintptr_t)offset); 1038} 1039 1040/* 1041 * Dereference MDT_VERSION metadata into module name and version 1042 */ 1043static void 1044linker_mdt_version(linker_file_t lf, struct mod_metadata *mp, 1045 const char **modname, int *version) 1046{ 1047 struct mod_version *mvp; 1048 1049 if (modname) 1050 *modname = linker_reloc_ptr(lf, mp->md_cval); 1051 if (version) { 1052 mvp = linker_reloc_ptr(lf, mp->md_data); 1053 *version = mvp->mv_version; 1054 } 1055} 1056 1057/* 1058 * Dereference MDT_DEPEND metadata into module name and mod_depend structure 1059 */ 1060static void 1061linker_mdt_depend(linker_file_t lf, struct mod_metadata *mp, 1062 const char **modname, struct mod_depend **verinfo) 1063{ 1064 1065 if (modname) 1066 *modname = linker_reloc_ptr(lf, mp->md_cval); 1067 if (verinfo) 1068 *verinfo = linker_reloc_ptr(lf, mp->md_data); 1069} 1070 1071static void 1072linker_addmodules(linker_file_t lf, struct mod_metadata **start, 1073 struct mod_metadata **stop, int preload) 1074{ 1075 struct mod_metadata *mp, **mdp; 1076 const char *modname; 1077 int ver; 1078 1079 for (mdp = start; mdp < stop; mdp++) { 1080 if (preload) 1081 mp = *mdp; 1082 else 1083 mp = linker_reloc_ptr(lf, *mdp); 1084 if (mp->md_type != MDT_VERSION) 1085 continue; 1086 if (preload) { 1087 modname = mp->md_cval; 1088 ver = ((struct mod_version *)mp->md_data)->mv_version; 1089 } else 1090 linker_mdt_version(lf, mp, &modname, &ver); 1091 if (modlist_lookup(modname, ver) != NULL) { 1092 printf("module %s already present!\n", modname); 1093 /* XXX what can we do? this is a build error. :-( */ 1094 continue; 1095 } 1096 modlist_newmodule(modname, ver, lf); 1097 } 1098} 1099 1100static void 1101linker_preload(void *arg) 1102{ 1103 caddr_t modptr; 1104 const char *modname, *nmodname; 1105 char *modtype; 1106 linker_file_t lf; 1107 linker_class_t lc; 1108 int error; 1109 linker_file_list_t loaded_files; 1110 linker_file_list_t depended_files; 1111 struct mod_metadata *mp, *nmp; 1112 struct mod_metadata **start, **stop, **mdp, **nmdp; 1113 struct mod_depend *verinfo; 1114 int nver; 1115 int resolves; 1116 modlist_t mod; 1117 struct sysinit **si_start, **si_stop; 1118 1119 TAILQ_INIT(&loaded_files); 1120 TAILQ_INIT(&depended_files); 1121 TAILQ_INIT(&found_modules); 1122 error = 0; 1123 1124 modptr = NULL; 1125 while ((modptr = preload_search_next_name(modptr)) != NULL) { 1126 modname = (char *)preload_search_info(modptr, MODINFO_NAME); 1127 modtype = (char *)preload_search_info(modptr, MODINFO_TYPE); 1128 if (modname == NULL) { 1129 printf("Preloaded module at %p does not have a" 1130 " name!\n", modptr); 1131 continue; 1132 } 1133 if (modtype == NULL) { 1134 printf("Preloaded module at %p does not have a type!\n", 1135 modptr); 1136 continue; 1137 } 1138 printf("Preloaded %s \"%s\" at %p.\n", modtype, modname, 1139 modptr); 1140 lf = NULL; 1141 TAILQ_FOREACH(lc, &classes, link) { 1142 error = LINKER_LINK_PRELOAD(lc, modname, &lf); 1143 if (error) { 1144 lf = NULL; 1145 break; 1146 } 1147 } 1148 if (lf) 1149 TAILQ_INSERT_TAIL(&loaded_files, lf, loaded); 1150 } 1151 1152 /* 1153 * First get a list of stuff in the kernel. 1154 */ 1155 if (linker_file_lookup_set(linker_kernel_file, MDT_SETNAME, &start, 1156 &stop, NULL) == 0) 1157 linker_addmodules(linker_kernel_file, start, stop, 1); 1158 1159 /* 1160 * this is a once-off kinky bubble sort resolve relocation dependency 1161 * requirements 1162 */ 1163restart: 1164 TAILQ_FOREACH(lf, &loaded_files, loaded) { 1165 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1166 &stop, NULL); 1167 /* 1168 * First, look to see if we would successfully link with this 1169 * stuff. 1170 */ 1171 resolves = 1; /* unless we know otherwise */ 1172 if (!error) { 1173 for (mdp = start; mdp < stop; mdp++) { 1174 mp = linker_reloc_ptr(lf, *mdp); 1175 if (mp->md_type != MDT_DEPEND) 1176 continue; 1177 linker_mdt_depend(lf, mp, &modname, &verinfo); 1178 for (nmdp = start; nmdp < stop; nmdp++) { 1179 nmp = linker_reloc_ptr(lf, *nmdp); 1180 if (nmp->md_type != MDT_VERSION) 1181 continue; 1182 linker_mdt_version(lf, nmp, &nmodname, 1183 NULL); 1184 nmodname = linker_reloc_ptr(lf, 1185 nmp->md_cval); 1186 if (strcmp(modname, nmodname) == 0) 1187 break; 1188 } 1189 if (nmdp < stop) /* it's a self reference */ 1190 continue; 1191 1192 /* 1193 * ok, the module isn't here yet, we 1194 * are not finished 1195 */ 1196 if (modlist_lookup2(modname, verinfo) == NULL) 1197 resolves = 0; 1198 } 1199 } 1200 /* 1201 * OK, if we found our modules, we can link. So, "provide" 1202 * the modules inside and add it to the end of the link order 1203 * list. 1204 */ 1205 if (resolves) { 1206 if (!error) { 1207 for (mdp = start; mdp < stop; mdp++) { 1208 mp = linker_reloc_ptr(lf, *mdp); 1209 if (mp->md_type != MDT_VERSION) 1210 continue; 1211 linker_mdt_version(lf, mp, 1212 &modname, &nver); 1213 if (modlist_lookup(modname, 1214 nver) != NULL) { 1215 printf("module %s already" 1216 " present!\n", modname); 1217 linker_file_unload(lf); 1218 TAILQ_REMOVE(&loaded_files, 1219 lf, loaded); 1220 /* we changed tailq next ptr */ 1221 goto restart; 1222 } 1223 modlist_newmodule(modname, nver, lf); 1224 } 1225 } 1226 TAILQ_REMOVE(&loaded_files, lf, loaded); 1227 TAILQ_INSERT_TAIL(&depended_files, lf, loaded); 1228 /* 1229 * Since we provided modules, we need to restart the 1230 * sort so that the previous files that depend on us 1231 * have a chance. Also, we've busted the tailq next 1232 * pointer with the REMOVE. 1233 */ 1234 goto restart; 1235 } 1236 } 1237 1238 /* 1239 * At this point, we check to see what could not be resolved.. 1240 */ 1241 TAILQ_FOREACH(lf, &loaded_files, loaded) { 1242 printf("KLD file %s is missing dependencies\n", lf->filename); 1243 linker_file_unload(lf); 1244 TAILQ_REMOVE(&loaded_files, lf, loaded); 1245 } 1246 1247 /* 1248 * We made it. Finish off the linking in the order we determined. 1249 */ 1250 TAILQ_FOREACH(lf, &depended_files, loaded) { 1251 if (linker_kernel_file) { 1252 linker_kernel_file->refs++; 1253 error = linker_file_add_dependency(lf, 1254 linker_kernel_file); 1255 if (error) 1256 panic("cannot add dependency"); 1257 } 1258 lf->userrefs++; /* so we can (try to) kldunload it */ 1259 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, 1260 &stop, NULL); 1261 if (!error) { 1262 for (mdp = start; mdp < stop; mdp++) { 1263 mp = linker_reloc_ptr(lf, *mdp); 1264 if (mp->md_type != MDT_DEPEND) 1265 continue; 1266 linker_mdt_depend(lf, mp, &modname, &verinfo); 1267 mod = modlist_lookup2(modname, verinfo); 1268 mod->container->refs++; 1269 error = linker_file_add_dependency(lf, 1270 mod->container); 1271 if (error) 1272 panic("cannot add dependency"); 1273 } 1274 } 1275 /* 1276 * Now do relocation etc using the symbol search paths 1277 * established by the dependencies 1278 */ 1279 error = LINKER_LINK_PRELOAD_FINISH(lf); 1280 if (error) { 1281 printf("KLD file %s - could not finalize loading\n", 1282 lf->filename); 1283 linker_file_unload(lf); 1284 continue; 1285 } 1286 linker_file_register_modules(lf); 1287 if (linker_file_lookup_set(lf, "sysinit_set", &si_start, 1288 &si_stop, NULL) == 0) 1289 sysinit_add(si_start, si_stop); 1290 linker_file_register_sysctls(lf); 1291 lf->flags |= LINKER_FILE_LINKED; 1292 } 1293 /* woohoo! we made it! */ 1294} 1295 1296SYSINIT(preload, SI_SUB_KLD, SI_ORDER_MIDDLE, linker_preload, 0) 1297 1298/* 1299 * Search for a not-loaded module by name. 1300 * 1301 * Modules may be found in the following locations: 1302 * 1303 * - preloaded (result is just the module name) - on disk (result is full path 1304 * to module) 1305 * 1306 * If the module name is qualified in any way (contains path, etc.) the we 1307 * simply return a copy of it. 1308 * 1309 * The search path can be manipulated via sysctl. Note that we use the ';' 1310 * character as a separator to be consistent with the bootloader. 1311 */ 1312 1313static char linker_hintfile[] = "linker.hints"; 1314static char linker_path[MAXPATHLEN] = "/boot/kernel;/boot/modules;/modules"; 1315 1316SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RW, linker_path, 1317 sizeof(linker_path), "module load search path"); 1318 1319TUNABLE_STR("module_path", linker_path, sizeof(linker_path)); 1320 1321static char *linker_ext_list[] = { 1322 "", 1323 ".ko", 1324 NULL 1325}; 1326 1327/* 1328 * Check if file actually exists either with or without extension listed in 1329 * the linker_ext_list. (probably should be generic for the rest of the 1330 * kernel) 1331 */ 1332static char * 1333linker_lookup_file(const char *path, int pathlen, const char *name, 1334 int namelen, struct vattr *vap) 1335{ 1336 struct nameidata nd; 1337 struct thread *td = curthread; /* XXX */ 1338 char *result, **cpp, *sep; 1339 int error, len, extlen, reclen, flags; 1340 enum vtype type; 1341 1342 extlen = 0; 1343 for (cpp = linker_ext_list; *cpp; cpp++) { 1344 len = strlen(*cpp); 1345 if (len > extlen) 1346 extlen = len; 1347 } 1348 extlen++; /* trailing '\0' */ 1349 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1350 1351 reclen = pathlen + strlen(sep) + namelen + extlen + 1; 1352 result = malloc(reclen, M_LINKER, M_WAITOK); 1353 for (cpp = linker_ext_list; *cpp; cpp++) { 1354 snprintf(result, reclen, "%.*s%s%.*s%s", pathlen, path, sep, 1355 namelen, name, *cpp); 1356 /* 1357 * Attempt to open the file, and return the path if 1358 * we succeed and it's a regular file. 1359 */ 1360 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, result, td); 1361 flags = FREAD; 1362 error = vn_open(&nd, &flags, 0); 1363 if (error == 0) { 1364 NDFREE(&nd, NDF_ONLY_PNBUF); 1365 type = nd.ni_vp->v_type; 1366 if (vap) 1367 VOP_GETATTR(nd.ni_vp, vap, td->td_ucred, td); 1368 VOP_UNLOCK(nd.ni_vp, 0, td); 1369 vn_close(nd.ni_vp, FREAD, td->td_ucred, td); 1370 if (type == VREG) 1371 return (result); 1372 } 1373 } 1374 free(result, M_LINKER); 1375 return (NULL); 1376} 1377 1378#define INT_ALIGN(base, ptr) ptr = \ 1379 (base) + (((ptr) - (base) + sizeof(int) - 1) & ~(sizeof(int) - 1)) 1380 1381/* 1382 * Lookup KLD which contains requested module in the "linker.hints" file. If 1383 * version specification is available, then try to find the best KLD. 1384 * Otherwise just find the latest one. 1385 * 1386 * XXX: Vnode locking here is hosed; lock should be held for calls to 1387 * VOP_GETATTR() and vn_rdwr(). 1388 */ 1389static char * 1390linker_hints_lookup(const char *path, int pathlen, const char *modname, 1391 int modnamelen, struct mod_depend *verinfo) 1392{ 1393 struct thread *td = curthread; /* XXX */ 1394 struct ucred *cred = td ? td->td_ucred : NULL; 1395 struct nameidata nd; 1396 struct vattr vattr, mattr; 1397 u_char *hints = NULL; 1398 u_char *cp, *recptr, *bufend, *result, *best, *pathbuf, *sep; 1399 int error, ival, bestver, *intp, reclen, found, flags, clen, blen; 1400 1401 result = NULL; 1402 bestver = found = 0; 1403 1404 sep = (path[pathlen - 1] != '/') ? "/" : ""; 1405 reclen = imax(modnamelen, strlen(linker_hintfile)) + pathlen + 1406 strlen(sep) + 1; 1407 pathbuf = malloc(reclen, M_LINKER, M_WAITOK); 1408 snprintf(pathbuf, reclen, "%.*s%s%s", pathlen, path, sep, 1409 linker_hintfile); 1410 1411 NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, pathbuf, td); 1412 flags = FREAD; 1413 error = vn_open(&nd, &flags, 0); 1414 if (error) 1415 goto bad; 1416 NDFREE(&nd, NDF_ONLY_PNBUF); 1417 VOP_UNLOCK(nd.ni_vp, 0, td); 1418 if (nd.ni_vp->v_type != VREG) 1419 goto bad; 1420 best = cp = NULL; 1421 error = VOP_GETATTR(nd.ni_vp, &vattr, cred, td); 1422 if (error) 1423 goto bad; 1424 /* 1425 * XXX: we need to limit this number to some reasonable value 1426 */ 1427 if (vattr.va_size > 100 * 1024) { 1428 printf("hints file too large %ld\n", (long)vattr.va_size); 1429 goto bad; 1430 } 1431 hints = malloc(vattr.va_size, M_TEMP, M_WAITOK); 1432 if (hints == NULL) 1433 goto bad; 1434 error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)hints, vattr.va_size, 0, 1435 UIO_SYSSPACE, IO_NODELOCKED, cred, &reclen, td); 1436 if (error) 1437 goto bad; 1438 vn_close(nd.ni_vp, FREAD, cred, td); 1439 nd.ni_vp = NULL; 1440 if (reclen != 0) { 1441 printf("can't read %d\n", reclen); 1442 goto bad; 1443 } 1444 intp = (int *)hints; 1445 ival = *intp++; 1446 if (ival != LINKER_HINTS_VERSION) { 1447 printf("hints file version mismatch %d\n", ival); 1448 goto bad; 1449 } 1450 bufend = hints + vattr.va_size; 1451 recptr = (u_char *)intp; 1452 clen = blen = 0; 1453 while (recptr < bufend && !found) { 1454 intp = (int *)recptr; 1455 reclen = *intp++; 1456 ival = *intp++; 1457 cp = (char *)intp; 1458 switch (ival) { 1459 case MDT_VERSION: 1460 clen = *cp++; 1461 if (clen != modnamelen || bcmp(cp, modname, clen) != 0) 1462 break; 1463 cp += clen; 1464 INT_ALIGN(hints, cp); 1465 ival = *(int *)cp; 1466 cp += sizeof(int); 1467 clen = *cp++; 1468 if (verinfo == NULL || 1469 ival == verinfo->md_ver_preferred) { 1470 found = 1; 1471 break; 1472 } 1473 if (ival >= verinfo->md_ver_minimum && 1474 ival <= verinfo->md_ver_maximum && 1475 ival > bestver) { 1476 bestver = ival; 1477 best = cp; 1478 blen = clen; 1479 } 1480 break; 1481 default: 1482 break; 1483 } 1484 recptr += reclen + sizeof(int); 1485 } 1486 /* 1487 * Finally check if KLD is in the place 1488 */ 1489 if (found) 1490 result = linker_lookup_file(path, pathlen, cp, clen, &mattr); 1491 else if (best) 1492 result = linker_lookup_file(path, pathlen, best, blen, &mattr); 1493 1494 /* 1495 * KLD is newer than hints file. What we should do now? 1496 */ 1497 if (result && timespeccmp(&mattr.va_mtime, &vattr.va_mtime, >)) 1498 printf("warning: KLD '%s' is newer than the linker.hints" 1499 " file\n", result); 1500bad: 1501 if (hints) 1502 free(hints, M_TEMP); 1503 if (nd.ni_vp != NULL) 1504 vn_close(nd.ni_vp, FREAD, cred, td); 1505 /* 1506 * If nothing found or hints is absent - fallback to the old 1507 * way by using "kldname[.ko]" as module name. 1508 */ 1509 if (!found && !bestver && result == NULL) 1510 result = linker_lookup_file(path, pathlen, modname, 1511 modnamelen, NULL); 1512 return (result); 1513} 1514 1515/* 1516 * Lookup KLD which contains requested module in the all directories. 1517 */ 1518static char * 1519linker_search_module(const char *modname, int modnamelen, 1520 struct mod_depend *verinfo) 1521{ 1522 char *cp, *ep, *result; 1523 1524 /* 1525 * traverse the linker path 1526 */ 1527 for (cp = linker_path; *cp; cp = ep + 1) { 1528 /* find the end of this component */ 1529 for (ep = cp; (*ep != 0) && (*ep != ';'); ep++); 1530 result = linker_hints_lookup(cp, ep - cp, modname, 1531 modnamelen, verinfo); 1532 if (result != NULL) 1533 return (result); 1534 if (*ep == 0) 1535 break; 1536 } 1537 return (NULL); 1538} 1539 1540/* 1541 * Search for module in all directories listed in the linker_path. 1542 */ 1543static char * 1544linker_search_kld(const char *name) 1545{ 1546 char *cp, *ep, *result, **cpp; 1547 int extlen, len; 1548 1549 /* qualified at all? */ 1550 if (index(name, '/')) 1551 return (linker_strdup(name)); 1552 1553 extlen = 0; 1554 for (cpp = linker_ext_list; *cpp; cpp++) { 1555 len = strlen(*cpp); 1556 if (len > extlen) 1557 extlen = len; 1558 } 1559 extlen++; /* trailing '\0' */ 1560 1561 /* traverse the linker path */ 1562 len = strlen(name); 1563 for (ep = linker_path; *ep; ep++) { 1564 cp = ep; 1565 /* find the end of this component */ 1566 for (; *ep != 0 && *ep != ';'; ep++); 1567 result = linker_lookup_file(cp, ep - cp, name, len, NULL); 1568 if (result != NULL) 1569 return (result); 1570 } 1571 return (NULL); 1572} 1573 1574static const char * 1575linker_basename(const char *path) 1576{ 1577 const char *filename; 1578 1579 filename = rindex(path, '/'); 1580 if (filename == NULL) 1581 return path; 1582 if (filename[1]) 1583 filename++; 1584 return (filename); 1585} 1586 1587/* 1588 * Find a file which contains given module and load it, if "parent" is not 1589 * NULL, register a reference to it. 1590 */ 1591static int 1592linker_load_module(const char *kldname, const char *modname, 1593 struct linker_file *parent, struct mod_depend *verinfo, 1594 struct linker_file **lfpp) 1595{ 1596 linker_file_t lfdep; 1597 const char *filename; 1598 char *pathname; 1599 int error; 1600 1601 if (modname == NULL) { 1602 /* 1603 * We have to load KLD 1604 */ 1605 KASSERT(verinfo == NULL, ("linker_load_module: verinfo" 1606 " is not NULL")); 1607 pathname = linker_search_kld(kldname); 1608 } else { 1609 if (modlist_lookup2(modname, verinfo) != NULL) 1610 return (EEXIST); 1611 if (kldname == NULL) 1612 /* 1613 * Need to find a KLD with required module 1614 */ 1615 pathname = linker_search_module(modname, 1616 strlen(modname), verinfo); 1617 else 1618 pathname = linker_strdup(kldname); 1619 } 1620 if (pathname == NULL) 1621 return (ENOENT); 1622 1623 /* 1624 * Can't load more than one file with the same basename XXX: 1625 * Actually it should be possible to have multiple KLDs with 1626 * the same basename but different path because they can 1627 * provide different versions of the same modules. 1628 */ 1629 filename = linker_basename(pathname); 1630 if (linker_find_file_by_name(filename)) { 1631 error = EEXIST; 1632 goto out; 1633 } 1634 do { 1635 error = linker_load_file(pathname, &lfdep); 1636 if (error) 1637 break; 1638 if (modname && verinfo && 1639 modlist_lookup2(modname, verinfo) == NULL) { 1640 linker_file_unload(lfdep); 1641 error = ENOENT; 1642 break; 1643 } 1644 if (parent) { 1645 error = linker_file_add_dependency(parent, lfdep); 1646 if (error) 1647 break; 1648 } 1649 if (lfpp) 1650 *lfpp = lfdep; 1651 } while (0); 1652out: 1653 if (pathname) 1654 free(pathname, M_LINKER); 1655 return (error); 1656} 1657 1658/* 1659 * This routine is responsible for finding dependencies of userland initiated 1660 * kldload(2)'s of files. 1661 */ 1662int 1663linker_load_dependencies(linker_file_t lf) 1664{ 1665 linker_file_t lfdep; 1666 struct mod_metadata **start, **stop, **mdp, **nmdp; 1667 struct mod_metadata *mp, *nmp; 1668 struct mod_depend *verinfo; 1669 modlist_t mod; 1670 const char *modname, *nmodname; 1671 int ver, error = 0, count; 1672 1673 /* 1674 * All files are dependant on /kernel. 1675 */ 1676 if (linker_kernel_file) { 1677 linker_kernel_file->refs++; 1678 error = linker_file_add_dependency(lf, linker_kernel_file); 1679 if (error) 1680 return (error); 1681 } 1682 if (linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop, 1683 &count) != 0) 1684 return (0); 1685 for (mdp = start; mdp < stop; mdp++) { 1686 mp = linker_reloc_ptr(lf, *mdp); 1687 if (mp->md_type != MDT_VERSION) 1688 continue; 1689 linker_mdt_version(lf, mp, &modname, &ver); 1690 mod = modlist_lookup(modname, ver); 1691 if (mod != NULL) { 1692 printf("interface %s.%d already present in the KLD" 1693 " '%s'!\n", modname, ver, 1694 mod->container->filename); 1695 return (EEXIST); 1696 } 1697 } 1698 1699 for (mdp = start; mdp < stop; mdp++) { 1700 mp = linker_reloc_ptr(lf, *mdp); 1701 if (mp->md_type != MDT_DEPEND) 1702 continue; 1703 linker_mdt_depend(lf, mp, &modname, &verinfo); 1704 nmodname = NULL; 1705 for (nmdp = start; nmdp < stop; nmdp++) { 1706 nmp = linker_reloc_ptr(lf, *nmdp); 1707 if (nmp->md_type != MDT_VERSION) 1708 continue; 1709 nmodname = linker_reloc_ptr(lf, nmp->md_cval); 1710 if (strcmp(modname, nmodname) == 0) 1711 break; 1712 } 1713 if (nmdp < stop)/* early exit, it's a self reference */ 1714 continue; 1715 mod = modlist_lookup2(modname, verinfo); 1716 if (mod) { /* woohoo, it's loaded already */ 1717 lfdep = mod->container; 1718 lfdep->refs++; 1719 error = linker_file_add_dependency(lf, lfdep); 1720 if (error) 1721 break; 1722 continue; 1723 } 1724 error = linker_load_module(NULL, modname, lf, verinfo, NULL); 1725 if (error) { 1726 printf("KLD %s: depends on %s - not available\n", 1727 lf->filename, modname); 1728 break; 1729 } 1730 } 1731 1732 if (error) 1733 return (error); 1734 linker_addmodules(lf, start, stop, 0); 1735 return (error); 1736} 1737 1738static int 1739sysctl_kern_function_list_iterate(const char *name, void *opaque) 1740{ 1741 struct sysctl_req *req; 1742 1743 req = opaque; 1744 return (SYSCTL_OUT(req, name, strlen(name) + 1)); 1745} 1746 1747/* 1748 * Export a nul-separated, double-nul-terminated list of all function names 1749 * in the kernel. 1750 */ 1751static int 1752sysctl_kern_function_list(SYSCTL_HANDLER_ARGS) 1753{ 1754 linker_file_t lf; 1755 int error; 1756 1757 TAILQ_FOREACH(lf, &linker_files, link) { 1758 error = LINKER_EACH_FUNCTION_NAME(lf, 1759 sysctl_kern_function_list_iterate, req); 1760 if (error) 1761 return (error); 1762 } 1763 return (SYSCTL_OUT(req, "", 1)); 1764} 1765 1766SYSCTL_PROC(_kern, OID_AUTO, function_list, CTLFLAG_RD, 1767 NULL, 0, sysctl_kern_function_list, "", "kernel function list"); 1768