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 1.39 2007/11/19 18:49:06 swildner 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/linker.h> 42 #include <sys/fcntl.h> 43 #include <sys/libkern.h> 44 #include <sys/nlookup.h> 45 #include <sys/vnode.h> 46 #include <sys/sysctl.h> 47 48 #include <vm/vm_zone.h> 49 50 #ifdef _KERNEL_VIRTUAL 51 #include <dlfcn.h> 52 #endif 53 54 #ifdef KLD_DEBUG 55 int kld_debug = 0; 56 #endif 57 58 /* Metadata from the static kernel */ 59 SET_DECLARE(modmetadata_set, struct mod_metadata); 60 MALLOC_DEFINE(M_LINKER, "kld", "kernel linker"); 61 62 linker_file_t linker_current_file; 63 linker_file_t linker_kernel_file; 64 65 static struct lock lock; /* lock for the file list */ 66 static linker_class_list_t classes; 67 static linker_file_list_t linker_files; 68 static int next_file_id = 1; 69 70 static void 71 linker_init(void* arg) 72 { 73 lockinit(&lock, "klink", 0, 0); 74 TAILQ_INIT(&classes); 75 TAILQ_INIT(&linker_files); 76 } 77 78 SYSINIT(linker, SI_BOOT2_KLD, SI_ORDER_FIRST, linker_init, 0); 79 80 int 81 linker_add_class(const char* desc, void* priv, 82 struct linker_class_ops* ops) 83 { 84 linker_class_t lc; 85 86 lc = kmalloc(sizeof(struct linker_class), M_LINKER, M_NOWAIT); 87 if (!lc) 88 return ENOMEM; 89 bzero(lc, sizeof(*lc)); 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 if (koname == NULL) { 265 error = ENOMEM; 266 goto out; 267 } 268 ksprintf(koname, "%s.ko", filename); 269 lf = NULL; 270 foundfile = 0; 271 for (lc = TAILQ_FIRST(&classes); lc; lc = TAILQ_NEXT(lc, link)) { 272 KLD_DPF(FILE, ("linker_load_file: trying to load %s as %s\n", 273 filename, lc->desc)); 274 275 error = lc->ops->load_file(koname, &lf); /* First with .ko */ 276 if (lf == NULL && error == ENOENT) 277 error = lc->ops->load_file(filename, &lf); /* Then try without */ 278 /* 279 * If we got something other than ENOENT, then it exists but we cannot 280 * load it for some other reason. 281 */ 282 if (error != ENOENT) 283 foundfile = 1; 284 if (lf) { 285 linker_file_register_sysctls(lf); 286 error = linker_file_sysinit(lf); 287 288 *result = lf; 289 goto out; 290 } 291 } 292 /* 293 * Less than ideal, but tells the user whether it failed to load or 294 * the module was not found. 295 */ 296 if (foundfile) { 297 /* 298 * Format not recognized or otherwise unloadable. 299 * When loading a module that is statically built into 300 * the kernel EEXIST percolates back up as the return 301 * value. Preserve this so that apps can recognize this 302 * special case. 303 */ 304 if (error != EEXIST) 305 error = ENOEXEC; 306 } else { 307 error = ENOENT; /* Nothing found */ 308 } 309 310 out: 311 if (koname) 312 kfree(koname, M_LINKER); 313 return error; 314 } 315 316 linker_file_t 317 linker_find_file_by_name(const char* filename) 318 { 319 linker_file_t lf = 0; 320 char *koname; 321 int i; 322 323 for (i = strlen(filename); i > 0 && filename[i-1] != '/'; --i) 324 ; 325 filename += i; 326 327 koname = kmalloc(strlen(filename) + 4, M_LINKER, M_WAITOK); 328 if (koname == NULL) 329 goto out; 330 ksprintf(koname, "%s.ko", filename); 331 332 lockmgr(&lock, LK_SHARED); 333 for (lf = TAILQ_FIRST(&linker_files); lf; lf = TAILQ_NEXT(lf, link)) { 334 if (!strcmp(lf->filename, koname)) 335 break; 336 if (!strcmp(lf->filename, filename)) 337 break; 338 } 339 lockmgr(&lock, LK_RELEASE); 340 341 out: 342 if (koname) 343 kfree(koname, M_LINKER); 344 return lf; 345 } 346 347 linker_file_t 348 linker_find_file_by_id(int fileid) 349 { 350 linker_file_t lf = 0; 351 352 lockmgr(&lock, LK_SHARED); 353 for (lf = TAILQ_FIRST(&linker_files); lf; lf = TAILQ_NEXT(lf, link)) 354 if (lf->id == fileid) 355 break; 356 lockmgr(&lock, LK_RELEASE); 357 358 return lf; 359 } 360 361 linker_file_t 362 linker_make_file(const char* pathname, void* priv, struct linker_file_ops* ops) 363 { 364 linker_file_t lf = 0; 365 int namelen; 366 const char *filename; 367 368 filename = rindex(pathname, '/'); 369 if (filename && filename[1]) 370 filename++; 371 else 372 filename = pathname; 373 374 KLD_DPF(FILE, ("linker_make_file: new file, filename=%s\n", filename)); 375 lockmgr(&lock, LK_EXCLUSIVE); 376 namelen = strlen(filename) + 1; 377 lf = kmalloc(sizeof(struct linker_file) + namelen, M_LINKER, M_WAITOK); 378 if (!lf) 379 goto out; 380 bzero(lf, sizeof(*lf)); 381 382 lf->refs = 1; 383 lf->userrefs = 0; 384 lf->flags = 0; 385 lf->filename = (char*) (lf + 1); 386 strcpy(lf->filename, filename); 387 lf->id = next_file_id++; 388 lf->ndeps = 0; 389 lf->deps = NULL; 390 STAILQ_INIT(&lf->common); 391 TAILQ_INIT(&lf->modules); 392 393 lf->priv = priv; 394 lf->ops = ops; 395 TAILQ_INSERT_TAIL(&linker_files, lf, link); 396 397 out: 398 lockmgr(&lock, LK_RELEASE); 399 return lf; 400 } 401 402 int 403 linker_file_unload(linker_file_t file) 404 { 405 module_t mod, next; 406 struct common_symbol* cp; 407 int error = 0; 408 int i; 409 410 /* Refuse to unload modules if securelevel raised */ 411 if (securelevel > 0 || kernel_mem_readonly) 412 return EPERM; 413 414 KLD_DPF(FILE, ("linker_file_unload: lf->refs=%d\n", file->refs)); 415 lockmgr(&lock, LK_EXCLUSIVE); 416 if (file->refs == 1) { 417 KLD_DPF(FILE, ("linker_file_unload: file is unloading, informing modules\n")); 418 /* 419 * Temporarily bump file->refs to prevent recursive unloading 420 */ 421 ++file->refs; 422 423 /* 424 * Inform any modules associated with this file. 425 */ 426 mod = TAILQ_FIRST(&file->modules); 427 while (mod) { 428 /* 429 * Give the module a chance to veto the unload. Note that the 430 * act of unloading the module may cause other modules in the 431 * same file list to be unloaded recursively. 432 */ 433 if ((error = module_unload(mod)) != 0) { 434 KLD_DPF(FILE, ("linker_file_unload: module %x vetoes unload\n", 435 mod)); 436 lockmgr(&lock, LK_RELEASE); 437 file->refs--; 438 goto out; 439 } 440 441 /* 442 * Recursive relationships may prevent the release from 443 * immediately removing the module, or may remove other 444 * modules in the list. 445 */ 446 next = module_getfnext(mod); 447 module_release(mod); 448 mod = next; 449 } 450 451 /* 452 * Since we intend to destroy the file structure, we expect all 453 * modules to have been removed by now. 454 */ 455 for (mod = TAILQ_FIRST(&file->modules); 456 mod; 457 mod = module_getfnext(mod) 458 ) { 459 kprintf("linker_file_unload: module %p still has refs!\n", mod); 460 } 461 --file->refs; 462 } 463 464 file->refs--; 465 if (file->refs > 0) { 466 lockmgr(&lock, LK_RELEASE); 467 goto out; 468 } 469 470 /* Don't try to run SYSUNINITs if we are unloaded due to a link error */ 471 if (file->flags & LINKER_FILE_LINKED) { 472 linker_file_sysuninit(file); 473 linker_file_unregister_sysctls(file); 474 } 475 476 TAILQ_REMOVE(&linker_files, file, link); 477 lockmgr(&lock, LK_RELEASE); 478 479 for (i = 0; i < file->ndeps; i++) 480 linker_file_unload(file->deps[i]); 481 kfree(file->deps, M_LINKER); 482 483 for (cp = STAILQ_FIRST(&file->common); cp; 484 cp = STAILQ_FIRST(&file->common)) { 485 STAILQ_REMOVE(&file->common, cp, common_symbol, link); 486 kfree(cp, M_LINKER); 487 } 488 489 file->ops->unload(file); 490 kfree(file, M_LINKER); 491 492 out: 493 return error; 494 } 495 496 int 497 linker_file_add_dependancy(linker_file_t file, linker_file_t dep) 498 { 499 linker_file_t* newdeps; 500 501 newdeps = kmalloc((file->ndeps + 1) * sizeof(linker_file_t*), 502 M_LINKER, M_WAITOK); 503 if (newdeps == NULL) 504 return ENOMEM; 505 bzero(newdeps, (file->ndeps + 1) * sizeof(linker_file_t*)); 506 507 if (file->deps) { 508 bcopy(file->deps, newdeps, file->ndeps * sizeof(linker_file_t*)); 509 kfree(file->deps, M_LINKER); 510 } 511 file->deps = newdeps; 512 file->deps[file->ndeps] = dep; 513 file->ndeps++; 514 515 return 0; 516 } 517 518 /* 519 * Locate a linker set and its contents. 520 * This is a helper function to avoid linker_if.h exposure elsewhere. 521 * Note: firstp and lastp are really void *** 522 */ 523 int 524 linker_file_lookup_set(linker_file_t file, const char *name, 525 void *firstp, void *lastp, int *countp) 526 { 527 return file->ops->lookup_set(file, name, firstp, lastp, countp); 528 } 529 530 int 531 linker_file_lookup_symbol(linker_file_t file, const char* name, int deps, caddr_t *raddr) 532 { 533 c_linker_sym_t sym; 534 linker_symval_t symval; 535 linker_file_t lf; 536 size_t common_size = 0; 537 int i; 538 539 KLD_DPF(SYM, ("linker_file_lookup_symbol: file=%x, name=%s, deps=%d\n", 540 file, name, deps)); 541 542 if (file->ops->lookup_symbol(file, name, &sym) == 0) { 543 file->ops->symbol_values(file, sym, &symval); 544 545 /* 546 * XXX Assume a common symbol if its value is 0 and it has a non-zero 547 * size, otherwise it could be an absolute symbol with a value of 0. 548 */ 549 if (symval.value == 0 && symval.size != 0) { 550 /* 551 * For commons, first look them up in the dependancies and 552 * only allocate space if not found there. 553 */ 554 common_size = symval.size; 555 } else { 556 KLD_DPF(SYM, ("linker_file_lookup_symbol: symbol.value=%x\n", symval.value)); 557 *raddr = symval.value; 558 return 0; 559 } 560 } 561 if (deps) { 562 for (i = 0; i < file->ndeps; i++) { 563 if (linker_file_lookup_symbol(file->deps[i], name, 0, raddr) == 0) { 564 KLD_DPF(SYM, ("linker_file_lookup_symbol: deps value=%x\n", *raddr)); 565 return 0; 566 } 567 } 568 569 /* If we have not found it in the dependencies, search globally */ 570 for (lf = TAILQ_FIRST(&linker_files); lf; lf = TAILQ_NEXT(lf, link)) { 571 /* But skip the current file if it's on the list */ 572 if (lf == file) 573 continue; 574 /* And skip the files we searched above */ 575 for (i = 0; i < file->ndeps; i++) 576 if (lf == file->deps[i]) 577 break; 578 if (i < file->ndeps) 579 continue; 580 if (linker_file_lookup_symbol(lf, name, 0, raddr) == 0) { 581 KLD_DPF(SYM, ("linker_file_lookup_symbol: global value=%x\n", *raddr)); 582 return 0; 583 } 584 } 585 } 586 587 if (common_size > 0) { 588 /* 589 * This is a common symbol which was not found in the 590 * dependancies. We maintain a simple common symbol table in 591 * the file object. 592 */ 593 struct common_symbol* cp; 594 595 for (cp = STAILQ_FIRST(&file->common); cp; 596 cp = STAILQ_NEXT(cp, link)) 597 if (!strcmp(cp->name, name)) { 598 KLD_DPF(SYM, ("linker_file_lookup_symbol: old common value=%x\n", cp->address)); 599 *raddr = cp->address; 600 return 0; 601 } 602 603 /* 604 * Round the symbol size up to align. 605 */ 606 common_size = (common_size + sizeof(int) - 1) & -sizeof(int); 607 cp = kmalloc(sizeof(struct common_symbol) 608 + common_size 609 + strlen(name) + 1, 610 M_LINKER, M_WAITOK); 611 if (!cp) { 612 KLD_DPF(SYM, ("linker_file_lookup_symbol: nomem\n")); 613 return ENOMEM; 614 } 615 bzero(cp, sizeof(struct common_symbol) + common_size + strlen(name)+ 1); 616 617 cp->address = (caddr_t) (cp + 1); 618 cp->name = cp->address + common_size; 619 strcpy(cp->name, name); 620 bzero(cp->address, common_size); 621 STAILQ_INSERT_TAIL(&file->common, cp, link); 622 623 KLD_DPF(SYM, ("linker_file_lookup_symbol: new common value=%x\n", cp->address)); 624 *raddr = cp->address; 625 return 0; 626 } 627 628 #ifdef _KERNEL_VIRTUAL 629 *raddr = dlsym(RTLD_NEXT, name); 630 if (*raddr != NULL) { 631 KLD_DPF(SYM, ("linker_file_lookup_symbol: found dlsym=%x\n", *raddr)); 632 return 0; 633 } 634 #endif 635 636 KLD_DPF(SYM, ("linker_file_lookup_symbol: fail\n")); 637 return ENOENT; 638 } 639 640 #ifdef DDB 641 /* 642 * DDB Helpers. DDB has to look across multiple files with their own 643 * symbol tables and string tables. 644 * 645 * Note that we do not obey list locking protocols here. We really don't 646 * need DDB to hang because somebody's got the lock held. We'll take the 647 * chance that the files list is inconsistant instead. 648 */ 649 650 int 651 linker_ddb_lookup(const char *symstr, c_linker_sym_t *sym) 652 { 653 linker_file_t lf; 654 655 for (lf = TAILQ_FIRST(&linker_files); lf; lf = TAILQ_NEXT(lf, link)) { 656 if (lf->ops->lookup_symbol(lf, symstr, sym) == 0) 657 return 0; 658 } 659 return ENOENT; 660 } 661 662 int 663 linker_ddb_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) 664 { 665 linker_file_t lf; 666 u_long off = (uintptr_t)value; 667 u_long diff, bestdiff; 668 c_linker_sym_t best; 669 c_linker_sym_t es; 670 671 best = 0; 672 bestdiff = off; 673 for (lf = TAILQ_FIRST(&linker_files); lf; lf = TAILQ_NEXT(lf, link)) { 674 if (lf->ops->search_symbol(lf, value, &es, &diff) != 0) 675 continue; 676 if (es != 0 && diff < bestdiff) { 677 best = es; 678 bestdiff = diff; 679 } 680 if (bestdiff == 0) 681 break; 682 } 683 if (best) { 684 *sym = best; 685 *diffp = bestdiff; 686 return 0; 687 } else { 688 *sym = 0; 689 *diffp = off; 690 return ENOENT; 691 } 692 } 693 694 int 695 linker_ddb_symbol_values(c_linker_sym_t sym, linker_symval_t *symval) 696 { 697 linker_file_t lf; 698 699 for (lf = TAILQ_FIRST(&linker_files); lf; lf = TAILQ_NEXT(lf, link)) { 700 if (lf->ops->symbol_values(lf, sym, symval) == 0) 701 return 0; 702 } 703 return ENOENT; 704 } 705 706 #endif 707 708 /* 709 * Syscalls. 710 */ 711 712 int 713 sys_kldload(struct kldload_args *uap) 714 { 715 struct thread *td = curthread; 716 char* filename = NULL, *modulename; 717 linker_file_t lf; 718 int error = 0; 719 720 uap->sysmsg_result = -1; 721 722 if (securelevel > 0 || kernel_mem_readonly) /* redundant, but that's OK */ 723 return EPERM; 724 725 if ((error = suser(td)) != 0) 726 return error; 727 728 filename = kmalloc(MAXPATHLEN, M_TEMP, M_WAITOK); 729 if ((error = copyinstr(uap->file, filename, MAXPATHLEN, NULL)) != 0) 730 goto out; 731 732 /* Can't load more than one module with the same name */ 733 modulename = rindex(filename, '/'); 734 if (modulename == NULL) 735 modulename = filename; 736 else 737 modulename++; 738 if (linker_find_file_by_name(modulename)) { 739 error = EEXIST; 740 goto out; 741 } 742 743 if ((error = linker_load_file(filename, &lf)) != 0) 744 goto out; 745 746 lf->userrefs++; 747 uap->sysmsg_result = lf->id; 748 749 out: 750 if (filename) 751 kfree(filename, M_TEMP); 752 return error; 753 } 754 755 int 756 sys_kldunload(struct kldunload_args *uap) 757 { 758 struct thread *td = curthread; 759 linker_file_t lf; 760 int error = 0; 761 762 if (securelevel > 0 || kernel_mem_readonly) /* redundant, but that's OK */ 763 return EPERM; 764 765 if ((error = suser(td)) != 0) 766 return error; 767 768 lf = linker_find_file_by_id(uap->fileid); 769 if (lf) { 770 KLD_DPF(FILE, ("kldunload: lf->userrefs=%d\n", lf->userrefs)); 771 if (lf->userrefs == 0) { 772 kprintf("linkerunload: attempt to unload file that was loaded by the kernel\n"); 773 error = EBUSY; 774 goto out; 775 } 776 lf->userrefs--; 777 error = linker_file_unload(lf); 778 if (error) 779 lf->userrefs++; 780 } else 781 error = ENOENT; 782 783 out: 784 return error; 785 } 786 787 int 788 sys_kldfind(struct kldfind_args *uap) 789 { 790 char *filename = NULL, *modulename; 791 linker_file_t lf; 792 int error = 0; 793 794 uap->sysmsg_result = -1; 795 796 filename = kmalloc(MAXPATHLEN, M_TEMP, M_WAITOK); 797 if ((error = copyinstr(uap->file, filename, MAXPATHLEN, NULL)) != 0) 798 goto out; 799 800 modulename = rindex(filename, '/'); 801 if (modulename == NULL) 802 modulename = filename; 803 804 lf = linker_find_file_by_name(modulename); 805 if (lf) 806 uap->sysmsg_result = lf->id; 807 else 808 error = ENOENT; 809 810 out: 811 if (filename) 812 kfree(filename, M_TEMP); 813 return error; 814 } 815 816 int 817 sys_kldnext(struct kldnext_args *uap) 818 { 819 linker_file_t lf; 820 int error = 0; 821 822 if (uap->fileid == 0) { 823 if (TAILQ_FIRST(&linker_files)) 824 uap->sysmsg_result = TAILQ_FIRST(&linker_files)->id; 825 else 826 uap->sysmsg_result = 0; 827 return 0; 828 } 829 830 lf = linker_find_file_by_id(uap->fileid); 831 if (lf) { 832 if (TAILQ_NEXT(lf, link)) 833 uap->sysmsg_result = TAILQ_NEXT(lf, link)->id; 834 else 835 uap->sysmsg_result = 0; 836 } else 837 error = ENOENT; 838 839 return error; 840 } 841 842 int 843 sys_kldstat(struct kldstat_args *uap) 844 { 845 linker_file_t lf; 846 int error = 0; 847 int version; 848 struct kld_file_stat* stat; 849 int namelen; 850 851 lf = linker_find_file_by_id(uap->fileid); 852 if (!lf) { 853 error = ENOENT; 854 goto out; 855 } 856 857 stat = uap->stat; 858 859 /* 860 * Check the version of the user's structure. 861 */ 862 if ((error = copyin(&stat->version, &version, sizeof(version))) != 0) 863 goto out; 864 if (version != sizeof(struct kld_file_stat)) { 865 error = EINVAL; 866 goto out; 867 } 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, sizeof(caddr_t))) != 0) 879 goto out; 880 if ((error = copyout(&lf->size, &stat->size, sizeof(size_t))) != 0) 881 goto out; 882 883 uap->sysmsg_result = 0; 884 885 out: 886 return error; 887 } 888 889 int 890 sys_kldfirstmod(struct kldfirstmod_args *uap) 891 { 892 linker_file_t lf; 893 int error = 0; 894 895 lf = linker_find_file_by_id(uap->fileid); 896 if (lf) { 897 if (TAILQ_FIRST(&lf->modules)) 898 uap->sysmsg_result = module_getid(TAILQ_FIRST(&lf->modules)); 899 else 900 uap->sysmsg_result = 0; 901 } else 902 error = ENOENT; 903 904 return error; 905 } 906 907 int 908 sys_kldsym(struct kldsym_args *uap) 909 { 910 char *symstr = NULL; 911 c_linker_sym_t sym; 912 linker_symval_t symval; 913 linker_file_t lf; 914 struct kld_sym_lookup lookup; 915 int error = 0; 916 917 if ((error = copyin(uap->data, &lookup, sizeof(lookup))) != 0) 918 goto out; 919 if (lookup.version != sizeof(lookup) || uap->cmd != KLDSYM_LOOKUP) { 920 error = EINVAL; 921 goto out; 922 } 923 924 symstr = kmalloc(MAXPATHLEN, M_TEMP, M_WAITOK); 925 if ((error = copyinstr(lookup.symname, symstr, MAXPATHLEN, NULL)) != 0) 926 goto out; 927 928 if (uap->fileid != 0) { 929 lf = linker_find_file_by_id(uap->fileid); 930 if (lf == NULL) { 931 error = ENOENT; 932 goto out; 933 } 934 if (lf->ops->lookup_symbol(lf, symstr, &sym) == 0 && 935 lf->ops->symbol_values(lf, sym, &symval) == 0) { 936 lookup.symvalue = (uintptr_t)symval.value; 937 lookup.symsize = symval.size; 938 error = copyout(&lookup, uap->data, sizeof(lookup)); 939 } else 940 error = ENOENT; 941 } else { 942 for (lf = TAILQ_FIRST(&linker_files); lf; lf = TAILQ_NEXT(lf, link)) { 943 if (lf->ops->lookup_symbol(lf, symstr, &sym) == 0 && 944 lf->ops->symbol_values(lf, sym, &symval) == 0) { 945 lookup.symvalue = (uintptr_t)symval.value; 946 lookup.symsize = symval.size; 947 error = copyout(&lookup, uap->data, sizeof(lookup)); 948 break; 949 } 950 } 951 if (!lf) 952 error = ENOENT; 953 } 954 out: 955 if (symstr) 956 kfree(symstr, M_TEMP); 957 return error; 958 } 959 960 /* 961 * Look for module metadata in the static kernel 962 */ 963 struct mod_metadata * 964 find_mod_metadata(const char *modname) 965 { 966 int len; 967 struct mod_metadata **mdp; 968 struct mod_metadata *mdt; 969 970 /* 971 * Strip path prefixes and any dot extension. MDT_MODULE names 972 * are just the module name without a path or ".ko". 973 */ 974 for (len = strlen(modname) - 1; len >= 0; --len) { 975 if (modname[len] == '/') 976 break; 977 } 978 modname += len + 1; 979 for (len = 0; modname[len] && modname[len] != '.'; ++len) 980 ; 981 982 /* 983 * Look for the module declaration 984 */ 985 SET_FOREACH(mdp, modmetadata_set) { 986 mdt = *mdp; 987 if (mdt->md_type != MDT_MODULE) 988 continue; 989 if (strlen(mdt->md_cval) == len && 990 strncmp(mdt->md_cval, modname, len) == 0) { 991 return(mdt); 992 } 993 } 994 return(NULL); 995 } 996 997 /* 998 * Preloaded module support 999 */ 1000 static void 1001 linker_preload(void* arg) 1002 { 1003 caddr_t modptr; 1004 char *modname; 1005 char *modtype; 1006 linker_file_t lf; 1007 linker_class_t lc; 1008 int error; 1009 struct sysinit **sipp; 1010 const moduledata_t *moddata; 1011 struct sysinit **si_start, **si_stop; 1012 1013 modptr = NULL; 1014 while ((modptr = preload_search_next_name(modptr)) != NULL) { 1015 modname = (char *)preload_search_info(modptr, MODINFO_NAME); 1016 modtype = (char *)preload_search_info(modptr, MODINFO_TYPE); 1017 if (modname == NULL) { 1018 kprintf("Preloaded module at %p does not have a name!\n", modptr); 1019 continue; 1020 } 1021 if (modtype == NULL) { 1022 kprintf("Preloaded module at %p does not have a type!\n", modptr); 1023 continue; 1024 } 1025 1026 /* 1027 * This is a hack at the moment, but what's in FreeBSD-5 is even 1028 * worse so I'd rather the hack. 1029 */ 1030 kprintf("Preloaded %s \"%s\" at %p", modtype, modname, modptr); 1031 if (find_mod_metadata(modname)) { 1032 kprintf(" (ignored, already in static kernel)\n"); 1033 continue; 1034 } 1035 kprintf(".\n"); 1036 1037 lf = linker_find_file_by_name(modname); 1038 if (lf) { 1039 lf->refs++; 1040 lf->userrefs++; 1041 continue; 1042 } 1043 lf = NULL; 1044 for (lc = TAILQ_FIRST(&classes); lc; lc = TAILQ_NEXT(lc, link)) { 1045 error = lc->ops->load_file(modname, &lf); 1046 if (error) { 1047 lf = NULL; 1048 break; 1049 } 1050 } 1051 if (lf) { 1052 lf->userrefs++; 1053 1054 if (linker_file_lookup_set(lf, "sysinit_set", &si_start, &si_stop, NULL) == 0) { 1055 /* HACK ALERT! 1056 * This is to set the sysinit moduledata so that the module 1057 * can attach itself to the correct containing file. 1058 * The sysinit could be run at *any* time. 1059 */ 1060 for (sipp = si_start; sipp < si_stop; sipp++) { 1061 if ((*sipp)->func == module_register_init) { 1062 moddata = (*sipp)->udata; 1063 error = module_register(moddata, lf); 1064 if (error) 1065 kprintf("Preloaded %s \"%s\" failed to register: %d\n", 1066 modtype, modname, error); 1067 } 1068 } 1069 sysinit_add(si_start, si_stop); 1070 } 1071 linker_file_register_sysctls(lf); 1072 } 1073 } 1074 } 1075 1076 SYSINIT(preload, SI_BOOT2_KLD, SI_ORDER_MIDDLE, linker_preload, 0); 1077 1078 /* 1079 * Search for a not-loaded module by name. 1080 * 1081 * Modules may be found in the following locations: 1082 * 1083 * - preloaded (result is just the module name) 1084 * - on disk (result is full path to module) 1085 * 1086 * If the module name is qualified in any way (contains path, etc.) 1087 * the we simply return a copy of it. 1088 * 1089 * The search path can be manipulated via sysctl. Note that we use the ';' 1090 * character as a separator to be consistent with the bootloader. 1091 */ 1092 1093 static char linker_path[MAXPATHLEN] = "/;/boot;/modules"; 1094 1095 SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RW, linker_path, 1096 sizeof(linker_path), "module load search path"); 1097 TUNABLE_STR("module_path", linker_path, sizeof(linker_path)); 1098 1099 static char * 1100 linker_strdup(const char *str) 1101 { 1102 char *result; 1103 1104 if ((result = kmalloc((strlen(str) + 1), M_LINKER, M_WAITOK)) != NULL) 1105 strcpy(result, str); 1106 return(result); 1107 } 1108 1109 char * 1110 linker_search_path(const char *name) 1111 { 1112 struct nlookupdata nd; 1113 char *cp, *ep, *result; 1114 size_t name_len, prefix_len; 1115 int sep; 1116 int error; 1117 enum vtype type; 1118 1119 /* qualified at all? */ 1120 if (index(name, '/')) 1121 return(linker_strdup(name)); 1122 1123 /* traverse the linker path */ 1124 cp = linker_path; 1125 name_len = strlen(name); 1126 for (;;) { 1127 1128 /* find the end of this component */ 1129 for (ep = cp; (*ep != 0) && (*ep != ';'); ep++) 1130 ; 1131 prefix_len = ep - cp; 1132 /* if this component doesn't end with a slash, add one */ 1133 if (ep == cp || *(ep - 1) != '/') 1134 sep = 1; 1135 else 1136 sep = 0; 1137 1138 /* 1139 * +2 : possible separator, plus terminator. 1140 */ 1141 result = kmalloc(prefix_len + name_len + 2, M_LINKER, M_WAITOK); 1142 1143 strncpy(result, cp, prefix_len); 1144 if (sep) 1145 result[prefix_len++] = '/'; 1146 strcpy(result + prefix_len, name); 1147 1148 /* 1149 * Attempt to open the file, and return the path if we succeed and it's 1150 * a regular file. 1151 */ 1152 error = nlookup_init(&nd, result, UIO_SYSSPACE, NLC_FOLLOW|NLC_LOCKVP); 1153 if (error == 0) 1154 error = vn_open(&nd, NULL, FREAD, 0); 1155 if (error == 0) { 1156 type = nd.nl_open_vp->v_type; 1157 if (type == VREG) { 1158 nlookup_done(&nd); 1159 return (result); 1160 } 1161 } 1162 nlookup_done(&nd); 1163 kfree(result, M_LINKER); 1164 1165 if (*ep == 0) 1166 break; 1167 cp = ep + 1; 1168 } 1169 return(NULL); 1170 } 1171