1 /*- 2 * Copyright (c) 1997 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: src/sys/kern/kern_linker.c,v 1.41.2.3 2001/11/21 17:50:35 luigi Exp $ 27 * $DragonFly: src/sys/kern/kern_linker.c,v 1.43 2008/02/06 22:37:46 nth Exp $ 28 */ 29 30 #include "opt_ddb.h" 31 32 #include <sys/param.h> 33 #include <sys/kernel.h> 34 #include <sys/systm.h> 35 #include <sys/malloc.h> 36 #include <sys/sysproto.h> 37 #include <sys/sysent.h> 38 #include <sys/proc.h> 39 #include <sys/lock.h> 40 #include <sys/module.h> 41 #include <sys/queue.h> 42 #include <sys/linker.h> 43 #include <sys/fcntl.h> 44 #include <sys/libkern.h> 45 #include <sys/nlookup.h> 46 #include <sys/vnode.h> 47 #include <sys/sysctl.h> 48 49 #include <vm/vm_zone.h> 50 51 #ifdef _KERNEL_VIRTUAL 52 #include <dlfcn.h> 53 #endif 54 55 #ifdef KLD_DEBUG 56 int kld_debug = 0; 57 #endif 58 59 /* Metadata from the static kernel */ 60 SET_DECLARE(modmetadata_set, struct mod_metadata); 61 MALLOC_DEFINE(M_LINKER, "kld", "kernel linker"); 62 63 linker_file_t linker_current_file; 64 linker_file_t linker_kernel_file; 65 66 static struct lock lock; /* lock for the file list */ 67 static linker_class_list_t classes; 68 static linker_file_list_t linker_files; 69 static int next_file_id = 1; 70 71 static void 72 linker_init(void* arg) 73 { 74 lockinit(&lock, "klink", 0, 0); 75 TAILQ_INIT(&classes); 76 TAILQ_INIT(&linker_files); 77 } 78 79 SYSINIT(linker, SI_BOOT2_KLD, SI_ORDER_FIRST, linker_init, 0); 80 81 int 82 linker_add_class(const char* desc, void* priv, 83 struct linker_class_ops* ops) 84 { 85 linker_class_t lc; 86 87 lc = kmalloc(sizeof(struct linker_class), M_LINKER, M_NOWAIT | M_ZERO); 88 if (!lc) 89 return ENOMEM; 90 91 lc->desc = desc; 92 lc->priv = priv; 93 lc->ops = ops; 94 TAILQ_INSERT_HEAD(&classes, lc, link); 95 96 return 0; 97 } 98 99 static int 100 linker_file_sysinit(linker_file_t lf) 101 { 102 struct sysinit** start, ** stop; 103 struct sysinit** sipp; 104 struct sysinit** xipp; 105 struct sysinit* save; 106 const moduledata_t *moddata; 107 int error; 108 109 KLD_DPF(FILE, ("linker_file_sysinit: calling SYSINITs for %s\n", 110 lf->filename)); 111 112 if (linker_file_lookup_set(lf, "sysinit_set", &start, &stop, NULL) != 0) 113 return 0; /* XXX is this correct ? No sysinit ? */ 114 115 /* HACK ALERT! */ 116 for (sipp = start; sipp < stop; sipp++) { 117 if ((*sipp)->func == module_register_init) { 118 moddata = (*sipp)->udata; 119 error = module_register(moddata, lf); 120 if (error) { 121 kprintf("linker_file_sysinit \"%s\" failed to register! %d\n", 122 lf->filename, error); 123 return error; 124 } 125 } 126 } 127 128 /* 129 * Perform a bubble sort of the system initialization objects by 130 * their subsystem (primary key) and order (secondary key). 131 * 132 * Since some things care about execution order, this is the 133 * operation which ensures continued function. 134 */ 135 for (sipp = start; sipp < stop; sipp++) { 136 for (xipp = sipp + 1; xipp < stop; xipp++) { 137 if ((*sipp)->subsystem < (*xipp)->subsystem || 138 ((*sipp)->subsystem == (*xipp)->subsystem && 139 (*sipp)->order <= (*xipp)->order)) 140 continue; /* skip*/ 141 save = *sipp; 142 *sipp = *xipp; 143 *xipp = save; 144 } 145 } 146 147 148 /* 149 * Traverse the (now) ordered list of system initialization tasks. 150 * Perform each task, and continue on to the next task. 151 */ 152 for (sipp = start; sipp < stop; sipp++) { 153 if ((*sipp)->subsystem == SI_SPECIAL_DUMMY) 154 continue; /* skip dummy task(s)*/ 155 156 /* Call function */ 157 (*((*sipp)->func))((*sipp)->udata); 158 } 159 return 0; /* no errors */ 160 } 161 162 static void 163 linker_file_sysuninit(linker_file_t lf) 164 { 165 struct sysinit** start, ** stop; 166 struct sysinit** sipp; 167 struct sysinit** xipp; 168 struct sysinit* save; 169 170 KLD_DPF(FILE, ("linker_file_sysuninit: calling SYSUNINITs for %s\n", 171 lf->filename)); 172 173 if (linker_file_lookup_set(lf, "sysuninit_set", &start, &stop, NULL) != 0) 174 return; 175 176 /* 177 * Perform a reverse bubble sort of the system initialization objects 178 * by their subsystem (primary key) and order (secondary key). 179 * 180 * Since some things care about execution order, this is the 181 * operation which ensures continued function. 182 */ 183 for (sipp = start; sipp < stop; sipp++) { 184 for (xipp = sipp + 1; xipp < stop; xipp++) { 185 if ((*sipp)->subsystem > (*xipp)->subsystem || 186 ((*sipp)->subsystem == (*xipp)->subsystem && 187 (*sipp)->order >= (*xipp)->order)) 188 continue; /* skip*/ 189 save = *sipp; 190 *sipp = *xipp; 191 *xipp = save; 192 } 193 } 194 195 196 /* 197 * Traverse the (now) ordered list of system initialization tasks. 198 * Perform each task, and continue on to the next task. 199 */ 200 for (sipp = start; sipp < stop; sipp++) { 201 if ((*sipp)->subsystem == SI_SPECIAL_DUMMY) 202 continue; /* skip dummy task(s)*/ 203 204 /* Call function */ 205 (*((*sipp)->func))((*sipp)->udata); 206 } 207 } 208 209 static void 210 linker_file_register_sysctls(linker_file_t lf) 211 { 212 struct sysctl_oid **start, **stop, **oidp; 213 214 KLD_DPF(FILE, ("linker_file_register_sysctls: registering SYSCTLs for %s\n", 215 lf->filename)); 216 217 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0) 218 return; 219 for (oidp = start; oidp < stop; oidp++) 220 sysctl_register_oid(*oidp); 221 } 222 223 static void 224 linker_file_unregister_sysctls(linker_file_t lf) 225 { 226 struct sysctl_oid **start, **stop, **oidp; 227 228 KLD_DPF(FILE, ("linker_file_unregister_sysctls: registering SYSCTLs for %s\n", 229 lf->filename)); 230 231 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0) 232 return; 233 for (oidp = start; oidp < stop; oidp++) 234 sysctl_unregister_oid(*oidp); 235 } 236 237 int 238 linker_load_file(const char* filename, linker_file_t* result) 239 { 240 linker_class_t lc; 241 linker_file_t lf; 242 int foundfile, error = 0; 243 char *koname = NULL; 244 245 /* Refuse to load modules if securelevel raised */ 246 if (securelevel > 0 || kernel_mem_readonly) 247 return EPERM; 248 249 lf = linker_find_file_by_name(filename); 250 if (lf) { 251 KLD_DPF(FILE, ("linker_load_file: file %s is already loaded, incrementing refs\n", filename)); 252 *result = lf; 253 lf->refs++; 254 goto out; 255 } 256 if (find_mod_metadata(filename)) { 257 if (linker_kernel_file) 258 ++linker_kernel_file->refs; 259 *result = linker_kernel_file; 260 goto out; 261 } 262 263 koname = kmalloc(strlen(filename) + 4, M_LINKER, M_WAITOK); 264 ksprintf(koname, "%s.ko", filename); 265 lf = NULL; 266 foundfile = 0; 267 TAILQ_FOREACH(lc, &classes, link) { 268 KLD_DPF(FILE, ("linker_load_file: trying to load %s as %s\n", 269 filename, lc->desc)); 270 271 error = lc->ops->load_file(koname, &lf); /* First with .ko */ 272 if (lf == NULL && error == ENOENT) 273 error = lc->ops->load_file(filename, &lf); /* Then try without */ 274 /* 275 * If we got something other than ENOENT, then it exists but we cannot 276 * load it for some other reason. 277 */ 278 if (error != ENOENT) 279 foundfile = 1; 280 if (lf) { 281 linker_file_register_sysctls(lf); 282 error = linker_file_sysinit(lf); 283 284 *result = lf; 285 goto out; 286 } 287 } 288 /* 289 * Less than ideal, but tells the user whether it failed to load or 290 * the module was not found. 291 */ 292 if (foundfile) { 293 /* 294 * Format not recognized or otherwise unloadable. 295 * When loading a module that is statically built into 296 * the kernel EEXIST percolates back up as the return 297 * value. Preserve this so that apps can recognize this 298 * special case. 299 */ 300 if (error != EEXIST) 301 error = ENOEXEC; 302 } else { 303 error = ENOENT; /* Nothing found */ 304 } 305 306 out: 307 if (koname) 308 kfree(koname, M_LINKER); 309 return error; 310 } 311 312 linker_file_t 313 linker_find_file_by_name(const char* filename) 314 { 315 linker_file_t lf = 0; 316 char *koname; 317 int i; 318 319 for (i = strlen(filename); i > 0 && filename[i-1] != '/'; --i) 320 ; 321 filename += i; 322 323 koname = kmalloc(strlen(filename) + 4, M_LINKER, M_WAITOK); 324 ksprintf(koname, "%s.ko", filename); 325 326 lockmgr(&lock, LK_SHARED); 327 TAILQ_FOREACH(lf, &linker_files, link) { 328 if (!strcmp(lf->filename, koname)) 329 break; 330 if (!strcmp(lf->filename, filename)) 331 break; 332 } 333 lockmgr(&lock, LK_RELEASE); 334 335 if (koname) 336 kfree(koname, M_LINKER); 337 return lf; 338 } 339 340 linker_file_t 341 linker_find_file_by_id(int fileid) 342 { 343 linker_file_t lf = 0; 344 345 lockmgr(&lock, LK_SHARED); 346 TAILQ_FOREACH(lf, &linker_files, link) 347 if (lf->id == fileid) 348 break; 349 lockmgr(&lock, LK_RELEASE); 350 351 return lf; 352 } 353 354 linker_file_t 355 linker_make_file(const char* pathname, void* priv, struct linker_file_ops* ops) 356 { 357 linker_file_t lf = 0; 358 int namelen; 359 const char *filename; 360 361 filename = rindex(pathname, '/'); 362 if (filename && filename[1]) 363 filename++; 364 else 365 filename = pathname; 366 367 KLD_DPF(FILE, ("linker_make_file: new file, filename=%s\n", filename)); 368 lockmgr(&lock, LK_EXCLUSIVE); 369 namelen = strlen(filename) + 1; 370 lf = kmalloc(sizeof(struct linker_file) + namelen, M_LINKER, M_WAITOK); 371 bzero(lf, sizeof(*lf)); 372 373 lf->refs = 1; 374 lf->userrefs = 0; 375 lf->flags = 0; 376 lf->filename = (char*) (lf + 1); 377 strcpy(lf->filename, filename); 378 lf->id = next_file_id++; 379 lf->ndeps = 0; 380 lf->deps = NULL; 381 STAILQ_INIT(&lf->common); 382 TAILQ_INIT(&lf->modules); 383 384 lf->priv = priv; 385 lf->ops = ops; 386 TAILQ_INSERT_TAIL(&linker_files, lf, link); 387 388 lockmgr(&lock, LK_RELEASE); 389 return lf; 390 } 391 392 int 393 linker_file_unload(linker_file_t file) 394 { 395 module_t mod, next; 396 struct common_symbol* cp; 397 int error = 0; 398 int i; 399 400 /* Refuse to unload modules if securelevel raised */ 401 if (securelevel > 0 || kernel_mem_readonly) 402 return EPERM; 403 404 KLD_DPF(FILE, ("linker_file_unload: lf->refs=%d\n", file->refs)); 405 lockmgr(&lock, LK_EXCLUSIVE); 406 if (file->refs == 1) { 407 KLD_DPF(FILE, ("linker_file_unload: file is unloading, informing modules\n")); 408 /* 409 * Temporarily bump file->refs to prevent recursive unloading 410 */ 411 ++file->refs; 412 413 /* 414 * Inform any modules associated with this file. 415 */ 416 mod = TAILQ_FIRST(&file->modules); 417 while (mod) { 418 /* 419 * Give the module a chance to veto the unload. Note that the 420 * act of unloading the module may cause other modules in the 421 * same file list to be unloaded recursively. 422 */ 423 if ((error = module_unload(mod)) != 0) { 424 KLD_DPF(FILE, ("linker_file_unload: module %x vetoes unload\n", 425 mod)); 426 lockmgr(&lock, LK_RELEASE); 427 file->refs--; 428 goto out; 429 } 430 431 /* 432 * Recursive relationships may prevent the release from 433 * immediately removing the module, or may remove other 434 * modules in the list. 435 */ 436 next = module_getfnext(mod); 437 module_release(mod); 438 mod = next; 439 } 440 441 /* 442 * Since we intend to destroy the file structure, we expect all 443 * modules to have been removed by now. 444 */ 445 for (mod = TAILQ_FIRST(&file->modules); 446 mod; 447 mod = module_getfnext(mod) 448 ) { 449 kprintf("linker_file_unload: module %p still has refs!\n", mod); 450 } 451 --file->refs; 452 } 453 454 file->refs--; 455 if (file->refs > 0) { 456 lockmgr(&lock, LK_RELEASE); 457 goto out; 458 } 459 460 /* Don't try to run SYSUNINITs if we are unloaded due to a link error */ 461 if (file->flags & LINKER_FILE_LINKED) { 462 linker_file_sysuninit(file); 463 linker_file_unregister_sysctls(file); 464 } 465 466 TAILQ_REMOVE(&linker_files, file, link); 467 lockmgr(&lock, LK_RELEASE); 468 469 for (i = 0; i < file->ndeps; i++) 470 linker_file_unload(file->deps[i]); 471 kfree(file->deps, M_LINKER); 472 473 for (cp = STAILQ_FIRST(&file->common); cp; 474 cp = STAILQ_FIRST(&file->common)) { 475 STAILQ_REMOVE(&file->common, cp, common_symbol, link); 476 kfree(cp, M_LINKER); 477 } 478 479 file->ops->unload(file); 480 kfree(file, M_LINKER); 481 482 out: 483 return error; 484 } 485 486 void 487 linker_file_add_dependancy(linker_file_t file, linker_file_t dep) 488 { 489 linker_file_t* newdeps; 490 491 newdeps = kmalloc((file->ndeps + 1) * sizeof(linker_file_t*), 492 M_LINKER, M_WAITOK | M_ZERO); 493 494 if (file->deps) { 495 bcopy(file->deps, newdeps, file->ndeps * sizeof(linker_file_t*)); 496 kfree(file->deps, M_LINKER); 497 } 498 file->deps = newdeps; 499 file->deps[file->ndeps] = dep; 500 file->ndeps++; 501 } 502 503 /* 504 * Locate a linker set and its contents. 505 * This is a helper function to avoid linker_if.h exposure elsewhere. 506 * Note: firstp and lastp are really void *** 507 */ 508 int 509 linker_file_lookup_set(linker_file_t file, const char *name, 510 void *firstp, void *lastp, int *countp) 511 { 512 return file->ops->lookup_set(file, name, firstp, lastp, countp); 513 } 514 515 int 516 linker_file_lookup_symbol(linker_file_t file, const char* name, int deps, caddr_t *raddr) 517 { 518 c_linker_sym_t sym; 519 linker_symval_t symval; 520 linker_file_t lf; 521 size_t common_size = 0; 522 int i; 523 524 KLD_DPF(SYM, ("linker_file_lookup_symbol: file=%x, name=%s, deps=%d\n", 525 file, name, deps)); 526 527 if (file->ops->lookup_symbol(file, name, &sym) == 0) { 528 file->ops->symbol_values(file, sym, &symval); 529 530 /* 531 * XXX Assume a common symbol if its value is 0 and it has a non-zero 532 * size, otherwise it could be an absolute symbol with a value of 0. 533 */ 534 if (symval.value == 0 && symval.size != 0) { 535 /* 536 * For commons, first look them up in the dependancies and 537 * only allocate space if not found there. 538 */ 539 common_size = symval.size; 540 } else { 541 KLD_DPF(SYM, ("linker_file_lookup_symbol: symbol.value=%x\n", symval.value)); 542 *raddr = symval.value; 543 return 0; 544 } 545 } 546 if (deps) { 547 for (i = 0; i < file->ndeps; i++) { 548 if (linker_file_lookup_symbol(file->deps[i], name, 0, raddr) == 0) { 549 KLD_DPF(SYM, ("linker_file_lookup_symbol: deps value=%x\n", *raddr)); 550 return 0; 551 } 552 } 553 554 /* If we have not found it in the dependencies, search globally */ 555 TAILQ_FOREACH(lf, &linker_files, link) { 556 /* But skip the current file if it's on the list */ 557 if (lf == file) 558 continue; 559 /* And skip the files we searched above */ 560 for (i = 0; i < file->ndeps; i++) 561 if (lf == file->deps[i]) 562 break; 563 if (i < file->ndeps) 564 continue; 565 if (linker_file_lookup_symbol(lf, name, 0, raddr) == 0) { 566 KLD_DPF(SYM, ("linker_file_lookup_symbol: global value=%x\n", *raddr)); 567 return 0; 568 } 569 } 570 } 571 572 if (common_size > 0) { 573 /* 574 * This is a common symbol which was not found in the 575 * dependancies. We maintain a simple common symbol table in 576 * the file object. 577 */ 578 struct common_symbol* cp; 579 580 STAILQ_FOREACH(cp, &file->common, link) 581 if (!strcmp(cp->name, name)) { 582 KLD_DPF(SYM, ("linker_file_lookup_symbol: old common value=%x\n", cp->address)); 583 *raddr = cp->address; 584 return 0; 585 } 586 587 /* 588 * Round the symbol size up to align. 589 */ 590 common_size = (common_size + sizeof(int) - 1) & -sizeof(int); 591 cp = kmalloc(sizeof(struct common_symbol) 592 + common_size 593 + strlen(name) + 1, 594 M_LINKER, M_WAITOK | M_ZERO); 595 596 cp->address = (caddr_t) (cp + 1); 597 cp->name = cp->address + common_size; 598 strcpy(cp->name, name); 599 bzero(cp->address, common_size); 600 STAILQ_INSERT_TAIL(&file->common, cp, link); 601 602 KLD_DPF(SYM, ("linker_file_lookup_symbol: new common value=%x\n", cp->address)); 603 *raddr = cp->address; 604 return 0; 605 } 606 607 #ifdef _KERNEL_VIRTUAL 608 *raddr = dlsym(RTLD_NEXT, name); 609 if (*raddr != NULL) { 610 KLD_DPF(SYM, ("linker_file_lookup_symbol: found dlsym=%x\n", *raddr)); 611 return 0; 612 } 613 #endif 614 615 KLD_DPF(SYM, ("linker_file_lookup_symbol: fail\n")); 616 return ENOENT; 617 } 618 619 #ifdef DDB 620 /* 621 * DDB Helpers. DDB has to look across multiple files with their own 622 * symbol tables and string tables. 623 * 624 * Note that we do not obey list locking protocols here. We really don't 625 * need DDB to hang because somebody's got the lock held. We'll take the 626 * chance that the files list is inconsistant instead. 627 */ 628 629 int 630 linker_ddb_lookup(const char *symstr, c_linker_sym_t *sym) 631 { 632 linker_file_t lf; 633 634 TAILQ_FOREACH(lf, &linker_files, link) { 635 if (lf->ops->lookup_symbol(lf, symstr, sym) == 0) 636 return 0; 637 } 638 return ENOENT; 639 } 640 641 int 642 linker_ddb_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) 643 { 644 linker_file_t lf; 645 u_long off = (uintptr_t)value; 646 u_long diff, bestdiff; 647 c_linker_sym_t best; 648 c_linker_sym_t es; 649 650 best = 0; 651 bestdiff = off; 652 TAILQ_FOREACH(lf, &linker_files, link) { 653 if (lf->ops->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 } 672 673 int 674 linker_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 (lf->ops->symbol_values(lf, sym, symval) == 0) 680 return 0; 681 } 682 return ENOENT; 683 } 684 685 #endif 686 687 /* 688 * Syscalls. 689 */ 690 691 int 692 sys_kldload(struct kldload_args *uap) 693 { 694 struct thread *td = curthread; 695 char* filename = NULL, *modulename; 696 linker_file_t lf; 697 int error = 0; 698 699 uap->sysmsg_result = -1; 700 701 if (securelevel > 0 || kernel_mem_readonly) /* redundant, but that's OK */ 702 return EPERM; 703 704 if ((error = suser(td)) != 0) 705 return error; 706 707 filename = kmalloc(MAXPATHLEN, M_TEMP, M_WAITOK); 708 if ((error = copyinstr(uap->file, filename, MAXPATHLEN, NULL)) != 0) 709 goto out; 710 711 /* Can't load more than one module with the same name */ 712 modulename = rindex(filename, '/'); 713 if (modulename == NULL) 714 modulename = filename; 715 else 716 modulename++; 717 if (linker_find_file_by_name(modulename)) { 718 error = EEXIST; 719 goto out; 720 } 721 722 if ((error = linker_load_file(filename, &lf)) != 0) 723 goto out; 724 725 lf->userrefs++; 726 uap->sysmsg_result = lf->id; 727 728 out: 729 if (filename) 730 kfree(filename, M_TEMP); 731 return error; 732 } 733 734 int 735 sys_kldunload(struct kldunload_args *uap) 736 { 737 struct thread *td = curthread; 738 linker_file_t lf; 739 int error = 0; 740 741 if (securelevel > 0 || kernel_mem_readonly) /* redundant, but that's OK */ 742 return EPERM; 743 744 if ((error = suser(td)) != 0) 745 return error; 746 747 lf = linker_find_file_by_id(uap->fileid); 748 if (lf) { 749 KLD_DPF(FILE, ("kldunload: lf->userrefs=%d\n", lf->userrefs)); 750 if (lf->userrefs == 0) { 751 kprintf("linkerunload: attempt to unload file that was loaded by the kernel\n"); 752 error = EBUSY; 753 goto out; 754 } 755 lf->userrefs--; 756 error = linker_file_unload(lf); 757 if (error) 758 lf->userrefs++; 759 } else 760 error = ENOENT; 761 762 out: 763 return error; 764 } 765 766 int 767 sys_kldfind(struct kldfind_args *uap) 768 { 769 char *filename = NULL, *modulename; 770 linker_file_t lf; 771 int error = 0; 772 773 uap->sysmsg_result = -1; 774 775 filename = kmalloc(MAXPATHLEN, M_TEMP, M_WAITOK); 776 if ((error = copyinstr(uap->file, filename, MAXPATHLEN, NULL)) != 0) 777 goto out; 778 779 modulename = rindex(filename, '/'); 780 if (modulename == NULL) 781 modulename = filename; 782 783 lf = linker_find_file_by_name(modulename); 784 if (lf) 785 uap->sysmsg_result = lf->id; 786 else 787 error = ENOENT; 788 789 out: 790 if (filename) 791 kfree(filename, M_TEMP); 792 return error; 793 } 794 795 int 796 sys_kldnext(struct kldnext_args *uap) 797 { 798 linker_file_t lf; 799 int error = 0; 800 801 if (uap->fileid == 0) { 802 if (TAILQ_FIRST(&linker_files)) 803 uap->sysmsg_result = TAILQ_FIRST(&linker_files)->id; 804 else 805 uap->sysmsg_result = 0; 806 return 0; 807 } 808 809 lf = linker_find_file_by_id(uap->fileid); 810 if (lf) { 811 if (TAILQ_NEXT(lf, link)) 812 uap->sysmsg_result = TAILQ_NEXT(lf, link)->id; 813 else 814 uap->sysmsg_result = 0; 815 } else 816 error = ENOENT; 817 818 return error; 819 } 820 821 int 822 sys_kldstat(struct kldstat_args *uap) 823 { 824 linker_file_t lf; 825 int error = 0; 826 int version; 827 struct kld_file_stat* stat; 828 int namelen; 829 830 lf = linker_find_file_by_id(uap->fileid); 831 if (!lf) { 832 error = ENOENT; 833 goto out; 834 } 835 836 stat = uap->stat; 837 838 /* 839 * Check the version of the user's structure. 840 */ 841 if ((error = copyin(&stat->version, &version, sizeof(version))) != 0) 842 goto out; 843 if (version != sizeof(struct kld_file_stat)) { 844 error = EINVAL; 845 goto out; 846 } 847 848 namelen = strlen(lf->filename) + 1; 849 if (namelen > MAXPATHLEN) 850 namelen = MAXPATHLEN; 851 if ((error = copyout(lf->filename, &stat->name[0], namelen)) != 0) 852 goto out; 853 if ((error = copyout(&lf->refs, &stat->refs, sizeof(int))) != 0) 854 goto out; 855 if ((error = copyout(&lf->id, &stat->id, sizeof(int))) != 0) 856 goto out; 857 if ((error = copyout(&lf->address, &stat->address, sizeof(caddr_t))) != 0) 858 goto out; 859 if ((error = copyout(&lf->size, &stat->size, sizeof(size_t))) != 0) 860 goto out; 861 862 uap->sysmsg_result = 0; 863 864 out: 865 return error; 866 } 867 868 int 869 sys_kldfirstmod(struct kldfirstmod_args *uap) 870 { 871 linker_file_t lf; 872 int error = 0; 873 874 lf = linker_find_file_by_id(uap->fileid); 875 if (lf) { 876 if (TAILQ_FIRST(&lf->modules)) 877 uap->sysmsg_result = module_getid(TAILQ_FIRST(&lf->modules)); 878 else 879 uap->sysmsg_result = 0; 880 } else 881 error = ENOENT; 882 883 return error; 884 } 885 886 int 887 sys_kldsym(struct kldsym_args *uap) 888 { 889 char *symstr = NULL; 890 c_linker_sym_t sym; 891 linker_symval_t symval; 892 linker_file_t lf; 893 struct kld_sym_lookup lookup; 894 int error = 0; 895 896 if ((error = copyin(uap->data, &lookup, sizeof(lookup))) != 0) 897 goto out; 898 if (lookup.version != sizeof(lookup) || uap->cmd != KLDSYM_LOOKUP) { 899 error = EINVAL; 900 goto out; 901 } 902 903 symstr = kmalloc(MAXPATHLEN, M_TEMP, M_WAITOK); 904 if ((error = copyinstr(lookup.symname, symstr, MAXPATHLEN, NULL)) != 0) 905 goto out; 906 907 if (uap->fileid != 0) { 908 lf = linker_find_file_by_id(uap->fileid); 909 if (lf == NULL) { 910 error = ENOENT; 911 goto out; 912 } 913 if (lf->ops->lookup_symbol(lf, symstr, &sym) == 0 && 914 lf->ops->symbol_values(lf, sym, &symval) == 0) { 915 lookup.symvalue = (uintptr_t)symval.value; 916 lookup.symsize = symval.size; 917 error = copyout(&lookup, uap->data, sizeof(lookup)); 918 } else 919 error = ENOENT; 920 } else { 921 TAILQ_FOREACH(lf, &linker_files, link) { 922 if (lf->ops->lookup_symbol(lf, symstr, &sym) == 0 && 923 lf->ops->symbol_values(lf, sym, &symval) == 0) { 924 lookup.symvalue = (uintptr_t)symval.value; 925 lookup.symsize = symval.size; 926 error = copyout(&lookup, uap->data, sizeof(lookup)); 927 break; 928 } 929 } 930 if (!lf) 931 error = ENOENT; 932 } 933 out: 934 if (symstr) 935 kfree(symstr, M_TEMP); 936 return error; 937 } 938 939 /* 940 * Look for module metadata in the static kernel 941 */ 942 struct mod_metadata * 943 find_mod_metadata(const char *modname) 944 { 945 int len; 946 struct mod_metadata **mdp; 947 struct mod_metadata *mdt; 948 949 /* 950 * Strip path prefixes and any dot extension. MDT_MODULE names 951 * are just the module name without a path or ".ko". 952 */ 953 for (len = strlen(modname) - 1; len >= 0; --len) { 954 if (modname[len] == '/') 955 break; 956 } 957 modname += len + 1; 958 for (len = 0; modname[len] && modname[len] != '.'; ++len) 959 ; 960 961 /* 962 * Look for the module declaration 963 */ 964 SET_FOREACH(mdp, modmetadata_set) { 965 mdt = *mdp; 966 if (mdt->md_type != MDT_MODULE) 967 continue; 968 if (strlen(mdt->md_cval) == len && 969 strncmp(mdt->md_cval, modname, len) == 0) { 970 return(mdt); 971 } 972 } 973 return(NULL); 974 } 975 976 /* 977 * Preloaded module support 978 */ 979 static void 980 linker_preload(void* arg) 981 { 982 caddr_t modptr; 983 char *modname; 984 char *modtype; 985 linker_file_t lf; 986 linker_class_t lc; 987 int error; 988 struct sysinit **sipp; 989 const moduledata_t *moddata; 990 struct sysinit **si_start, **si_stop; 991 992 modptr = NULL; 993 while ((modptr = preload_search_next_name(modptr)) != NULL) { 994 modname = (char *)preload_search_info(modptr, MODINFO_NAME); 995 modtype = (char *)preload_search_info(modptr, MODINFO_TYPE); 996 if (modname == NULL) { 997 kprintf("Preloaded module at %p does not have a name!\n", modptr); 998 continue; 999 } 1000 if (modtype == NULL) { 1001 kprintf("Preloaded module at %p does not have a type!\n", modptr); 1002 continue; 1003 } 1004 1005 /* 1006 * This is a hack at the moment, but what's in FreeBSD-5 is even 1007 * worse so I'd rather the hack. 1008 */ 1009 kprintf("Preloaded %s \"%s\" at %p", modtype, modname, modptr); 1010 if (find_mod_metadata(modname)) { 1011 kprintf(" (ignored, already in static kernel)\n"); 1012 continue; 1013 } 1014 kprintf(".\n"); 1015 1016 lf = linker_find_file_by_name(modname); 1017 if (lf) { 1018 lf->refs++; 1019 lf->userrefs++; 1020 continue; 1021 } 1022 lf = NULL; 1023 TAILQ_FOREACH(lc, &classes, link) { 1024 error = lc->ops->load_file(modname, &lf); 1025 if (error) { 1026 lf = NULL; 1027 break; 1028 } 1029 } 1030 if (lf) { 1031 lf->userrefs++; 1032 1033 if (linker_file_lookup_set(lf, "sysinit_set", &si_start, &si_stop, NULL) == 0) { 1034 /* HACK ALERT! 1035 * This is to set the sysinit moduledata so that the module 1036 * can attach itself to the correct containing file. 1037 * The sysinit could be run at *any* time. 1038 */ 1039 for (sipp = si_start; sipp < si_stop; sipp++) { 1040 if ((*sipp)->func == module_register_init) { 1041 moddata = (*sipp)->udata; 1042 error = module_register(moddata, lf); 1043 if (error) 1044 kprintf("Preloaded %s \"%s\" failed to register: %d\n", 1045 modtype, modname, error); 1046 } 1047 } 1048 sysinit_add(si_start, si_stop); 1049 } 1050 linker_file_register_sysctls(lf); 1051 } 1052 } 1053 } 1054 1055 SYSINIT(preload, SI_BOOT2_KLD, SI_ORDER_MIDDLE, linker_preload, 0); 1056 1057 /* 1058 * Search for a not-loaded module by name. 1059 * 1060 * Modules may be found in the following locations: 1061 * 1062 * - preloaded (result is just the module name) 1063 * - on disk (result is full path to module) 1064 * 1065 * If the module name is qualified in any way (contains path, etc.) 1066 * the we simply return a copy of it. 1067 * 1068 * The search path can be manipulated via sysctl. Note that we use the ';' 1069 * character as a separator to be consistent with the bootloader. 1070 */ 1071 1072 static char linker_path[MAXPATHLEN] = "/;/boot;/modules"; 1073 1074 SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RW, linker_path, 1075 sizeof(linker_path), "module load search path"); 1076 TUNABLE_STR("module_path", linker_path, sizeof(linker_path)); 1077 1078 static char * 1079 linker_strdup(const char *str) 1080 { 1081 char *result; 1082 1083 result = kmalloc(strlen(str) + 1, M_LINKER, M_WAITOK); 1084 strcpy(result, str); 1085 return(result); 1086 } 1087 1088 char * 1089 linker_search_path(const char *name) 1090 { 1091 struct nlookupdata nd; 1092 char *cp, *ep, *result; 1093 size_t name_len, prefix_len; 1094 int sep; 1095 int error; 1096 enum vtype type; 1097 1098 /* qualified at all? */ 1099 if (index(name, '/')) 1100 return(linker_strdup(name)); 1101 1102 /* traverse the linker path */ 1103 cp = linker_path; 1104 name_len = strlen(name); 1105 for (;;) { 1106 1107 /* find the end of this component */ 1108 for (ep = cp; (*ep != 0) && (*ep != ';'); ep++) 1109 ; 1110 prefix_len = ep - cp; 1111 /* if this component doesn't end with a slash, add one */ 1112 if (ep == cp || *(ep - 1) != '/') 1113 sep = 1; 1114 else 1115 sep = 0; 1116 1117 /* 1118 * +2 : possible separator, plus terminator. 1119 */ 1120 result = kmalloc(prefix_len + name_len + 2, M_LINKER, M_WAITOK); 1121 1122 strncpy(result, cp, prefix_len); 1123 if (sep) 1124 result[prefix_len++] = '/'; 1125 strcpy(result + prefix_len, name); 1126 1127 /* 1128 * Attempt to open the file, and return the path if we succeed and it's 1129 * a regular file. 1130 */ 1131 error = nlookup_init(&nd, result, UIO_SYSSPACE, NLC_FOLLOW|NLC_LOCKVP); 1132 if (error == 0) 1133 error = vn_open(&nd, NULL, FREAD, 0); 1134 if (error == 0) { 1135 type = nd.nl_open_vp->v_type; 1136 if (type == VREG) { 1137 nlookup_done(&nd); 1138 return (result); 1139 } 1140 } 1141 nlookup_done(&nd); 1142 kfree(result, M_LINKER); 1143 1144 if (*ep == 0) 1145 break; 1146 cp = ep + 1; 1147 } 1148 return(NULL); 1149 } 1150