kern_linker.c revision 70417
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 70417 2000-12-28 08:14:58Z peter $ 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/module.h> 40#include <sys/linker.h> 41#include <sys/fcntl.h> 42#include <sys/libkern.h> 43#include <sys/namei.h> 44#include <sys/vnode.h> 45#include <sys/sysctl.h> 46 47 48#include "linker_if.h" 49 50#ifdef KLD_DEBUG 51int kld_debug = 0; 52#endif 53 54static char *linker_search_path(const char *name); 55static const char *linker_basename(const char* path); 56 57MALLOC_DEFINE(M_LINKER, "linker", "kernel linker"); 58 59linker_file_t linker_kernel_file; 60 61static struct lock lock; /* lock for the file list */ 62static linker_class_list_t classes; 63static linker_file_list_t linker_files; 64static int next_file_id = 1; 65 66/* XXX wrong name; we're looking at version provision tags here, not modules */ 67typedef TAILQ_HEAD(, modlist) modlisthead_t; 68struct modlist { 69 TAILQ_ENTRY(modlist) link; /* chain together all modules */ 70 linker_file_t container; 71 const char *name; 72}; 73typedef struct modlist *modlist_t; 74static modlisthead_t found_modules; 75 76static char * 77linker_strdup(const char *str) 78{ 79 char *result; 80 81 if ((result = malloc((strlen(str) + 1), M_LINKER, M_WAITOK)) != NULL) 82 strcpy(result, str); 83 return(result); 84} 85 86static void 87linker_init(void* arg) 88{ 89 lockinit(&lock, PVM, "klink", 0, 0); 90 TAILQ_INIT(&classes); 91 TAILQ_INIT(&linker_files); 92} 93 94SYSINIT(linker, SI_SUB_KLD, SI_ORDER_FIRST, linker_init, 0); 95 96int 97linker_add_class(linker_class_t lc) 98{ 99 kobj_class_compile((kobj_class_t) lc); 100 TAILQ_INSERT_TAIL(&classes, lc, link); 101 return 0; 102} 103 104static void 105linker_file_sysinit(linker_file_t lf) 106{ 107 struct linker_set* sysinits; 108 struct sysinit** sipp; 109 struct sysinit** xipp; 110 struct sysinit* save; 111 112 KLD_DPF(FILE, ("linker_file_sysinit: calling SYSINITs for %s\n", 113 lf->filename)); 114 115 sysinits = (struct linker_set*) 116 linker_file_lookup_symbol(lf, "sysinit_set", 0); 117 118 KLD_DPF(FILE, ("linker_file_sysinit: SYSINITs %p\n", sysinits)); 119 if (!sysinits) 120 return; 121 /* 122 * Perform a bubble sort of the system initialization objects by 123 * their subsystem (primary key) and order (secondary key). 124 * 125 * Since some things care about execution order, this is the 126 * operation which ensures continued function. 127 */ 128 for (sipp = (struct sysinit **)sysinits->ls_items; *sipp; sipp++) { 129 for (xipp = sipp + 1; *xipp; xipp++) { 130 if ((*sipp)->subsystem < (*xipp)->subsystem || 131 ((*sipp)->subsystem == (*xipp)->subsystem && 132 (*sipp)->order <= (*xipp)->order)) 133 continue; /* skip*/ 134 save = *sipp; 135 *sipp = *xipp; 136 *xipp = save; 137 } 138 } 139 140 141 /* 142 * Traverse the (now) ordered list of system initialization tasks. 143 * Perform each task, and continue on to the next task. 144 */ 145 for (sipp = (struct sysinit **)sysinits->ls_items; *sipp; sipp++) { 146 if ((*sipp)->subsystem == SI_SUB_DUMMY) 147 continue; /* skip dummy task(s)*/ 148 149 /* Call function */ 150 (*((*sipp)->func))((*sipp)->udata); 151 } 152} 153 154static void 155linker_file_sysuninit(linker_file_t lf) 156{ 157 struct linker_set* sysuninits; 158 struct sysinit** sipp; 159 struct sysinit** xipp; 160 struct sysinit* save; 161 162 KLD_DPF(FILE, ("linker_file_sysuninit: calling SYSUNINITs for %s\n", 163 lf->filename)); 164 165 sysuninits = (struct linker_set*) 166 linker_file_lookup_symbol(lf, "sysuninit_set", 0); 167 168 KLD_DPF(FILE, ("linker_file_sysuninit: SYSUNINITs %p\n", sysuninits)); 169 if (!sysuninits) 170 return; 171 172 /* 173 * Perform a reverse bubble sort of the system initialization objects 174 * by their subsystem (primary key) and order (secondary key). 175 * 176 * Since some things care about execution order, this is the 177 * operation which ensures continued function. 178 */ 179 for (sipp = (struct sysinit **)sysuninits->ls_items; *sipp; sipp++) { 180 for (xipp = sipp + 1; *xipp; xipp++) { 181 if ((*sipp)->subsystem > (*xipp)->subsystem || 182 ((*sipp)->subsystem == (*xipp)->subsystem && 183 (*sipp)->order >= (*xipp)->order)) 184 continue; /* skip*/ 185 save = *sipp; 186 *sipp = *xipp; 187 *xipp = save; 188 } 189 } 190 191 /* 192 * Traverse the (now) ordered list of system initialization tasks. 193 * Perform each task, and continue on to the next task. 194 */ 195 for (sipp = (struct sysinit **)sysuninits->ls_items; *sipp; sipp++) { 196 if ((*sipp)->subsystem == SI_SUB_DUMMY) 197 continue; /* skip dummy task(s)*/ 198 199 /* Call function */ 200 (*((*sipp)->func))((*sipp)->udata); 201 } 202} 203 204static void 205linker_file_register_sysctls(linker_file_t lf) 206{ 207 struct linker_set* sysctls; 208 209 KLD_DPF(FILE, ("linker_file_register_sysctls: registering SYSCTLs for %s\n", 210 lf->filename)); 211 212 sysctls = (struct linker_set*) 213 linker_file_lookup_symbol(lf, "sysctl_set", 0); 214 215 KLD_DPF(FILE, ("linker_file_register_sysctls: SYSCTLs %p\n", sysctls)); 216 if (!sysctls) 217 return; 218 219 sysctl_register_set(sysctls); 220} 221 222static void 223linker_file_unregister_sysctls(linker_file_t lf) 224{ 225 struct linker_set* sysctls; 226 227 KLD_DPF(FILE, ("linker_file_unregister_sysctls: registering SYSCTLs for %s\n", 228 lf->filename)); 229 230 sysctls = (struct linker_set*) 231 linker_file_lookup_symbol(lf, "sysctl_set", 0); 232 233 KLD_DPF(FILE, ("linker_file_unregister_sysctls: SYSCTLs %p\n", sysctls)); 234 if (!sysctls) 235 return; 236 237 sysctl_unregister_set(sysctls); 238} 239 240extern struct linker_set modmetadata_set; 241 242static int 243linker_file_register_modules(linker_file_t lf) 244{ 245 int error, mcount; 246 struct linker_set *modules; 247 struct mod_metadata **mdpp; 248 const moduledata_t *moddata; 249 struct sysinit **sipp; 250 251 KLD_DPF(FILE, ("linker_file_register_modules: registering modules in %s\n", 252 lf->filename)); 253 254 modules = (struct linker_set*) 255 linker_file_lookup_symbol(lf, "modmetadata_set", 0); 256 257 if (!modules && lf == linker_kernel_file) 258 modules = &modmetadata_set; 259 260 mcount = 0; 261 if (modules) { 262 for (mdpp = (struct mod_metadata**)modules->ls_items; *mdpp; mdpp++) { 263 if ((*mdpp)->md_type != MDT_MODULE) 264 continue; 265 mcount++; 266 moddata = (*mdpp)->md_data; 267 KLD_DPF(FILE, ("Registering module %s in %s\n", 268 moddata->name, lf->filename)); 269 error = module_register(moddata, lf); 270 if (error) 271 printf("Module %s failed to register: %d\n", moddata->name, error); 272 } 273 } 274 if (mcount) 275 return mcount; /* Do not mix old and new style */ 276 277 /* Hack - handle old kld's without metadata */ 278 modules = (struct linker_set*) 279 linker_file_lookup_symbol(lf, "sysinit_set", 0); 280 if (modules) { 281 for (sipp = (struct sysinit **)modules->ls_items; *sipp; sipp++) { 282 if ((*sipp)->func != module_register_init) 283 continue; 284 mcount++; 285 moddata = (*sipp)->udata; 286 printf("Old-style KLD file %s found\n", moddata->name); 287 error = module_register(moddata, lf); 288 if (error) 289 printf("Old-style KLD file %s failed to register: %d\n", moddata->name, error); 290 } 291 } 292 return mcount; 293} 294 295static void 296linker_init_kernel_modules(void) 297{ 298 linker_file_register_modules(linker_kernel_file); 299} 300 301SYSINIT(linker_kernel, SI_SUB_KLD, SI_ORDER_ANY, linker_init_kernel_modules, 0); 302 303int 304linker_load_file(const char* filename, linker_file_t* result) 305{ 306 linker_class_t lc; 307 linker_file_t lf; 308 int foundfile, error = 0; 309 310 /* Refuse to load modules if securelevel raised */ 311 if (securelevel > 0) 312 return EPERM; 313 314 lf = linker_find_file_by_name(filename); 315 if (lf) { 316 KLD_DPF(FILE, ("linker_load_file: file %s is already loaded, incrementing refs\n", filename)); 317 *result = lf; 318 lf->refs++; 319 goto out; 320 } 321 322 lf = NULL; 323 foundfile = 0; 324 for (lc = TAILQ_FIRST(&classes); lc; lc = TAILQ_NEXT(lc, link)) { 325 KLD_DPF(FILE, ("linker_load_file: trying to load %s as %s\n", 326 filename, lc->desc)); 327 error = LINKER_LOAD_FILE(lc, filename, &lf); 328 /* 329 * If we got something other than ENOENT, then it exists but we cannot 330 * load it for some other reason. 331 */ 332 if (error != ENOENT) 333 foundfile = 1; 334 if (lf) { 335 linker_file_register_modules(lf); 336 linker_file_register_sysctls(lf); 337 linker_file_sysinit(lf); 338 lf->flags |= LINKER_FILE_LINKED; 339 340 *result = lf; 341 error = 0; 342 goto out; 343 } 344 } 345 /* 346 * Less than ideal, but tells the user whether it failed to load or 347 * the module was not found. 348 */ 349 if (foundfile) 350 error = ENOEXEC; /* Format not recognised (or unloadable) */ 351 else 352 error = ENOENT; /* Nothing found */ 353 354out: 355 return error; 356} 357 358linker_file_t 359linker_find_file_by_name(const char* filename) 360{ 361 linker_file_t lf = 0; 362 char *koname; 363 364 koname = malloc(strlen(filename) + 4, M_LINKER, M_WAITOK); 365 if (koname == NULL) 366 goto out; 367 sprintf(koname, "%s.ko", filename); 368 369 lockmgr(&lock, LK_SHARED, 0, curproc); 370 for (lf = TAILQ_FIRST(&linker_files); lf; lf = TAILQ_NEXT(lf, link)) { 371 if (!strcmp(lf->filename, koname)) 372 break; 373 if (!strcmp(lf->filename, filename)) 374 break; 375 } 376 lockmgr(&lock, LK_RELEASE, 0, curproc); 377 378out: 379 if (koname) 380 free(koname, M_LINKER); 381 return lf; 382} 383 384linker_file_t 385linker_find_file_by_id(int fileid) 386{ 387 linker_file_t lf = 0; 388 389 lockmgr(&lock, LK_SHARED, 0, curproc); 390 for (lf = TAILQ_FIRST(&linker_files); lf; lf = TAILQ_NEXT(lf, link)) 391 if (lf->id == fileid) 392 break; 393 lockmgr(&lock, LK_RELEASE, 0, curproc); 394 395 return lf; 396} 397 398linker_file_t 399linker_make_file(const char* pathname, linker_class_t lc) 400{ 401 linker_file_t lf = 0; 402 const char *filename; 403 404 filename = linker_basename(pathname); 405 406 KLD_DPF(FILE, ("linker_make_file: new file, filename=%s\n", filename)); 407 lockmgr(&lock, LK_EXCLUSIVE, 0, curproc); 408 lf = (linker_file_t) kobj_create((kobj_class_t) lc, M_LINKER, M_WAITOK); 409 if (!lf) 410 goto out; 411 412 lf->refs = 1; 413 lf->userrefs = 0; 414 lf->flags = 0; 415 lf->filename = linker_strdup(filename); 416 lf->id = next_file_id++; 417 lf->ndeps = 0; 418 lf->deps = NULL; 419 STAILQ_INIT(&lf->common); 420 TAILQ_INIT(&lf->modules); 421 422 TAILQ_INSERT_TAIL(&linker_files, lf, link); 423 424out: 425 lockmgr(&lock, LK_RELEASE, 0, curproc); 426 return lf; 427} 428 429int 430linker_file_unload(linker_file_t file) 431{ 432 module_t mod, next; 433 modlist_t ml, nextml; 434 struct common_symbol* cp; 435 int error = 0; 436 int i; 437 438 /* Refuse to unload modules if securelevel raised */ 439 if (securelevel > 0) 440 return EPERM; 441 442 KLD_DPF(FILE, ("linker_file_unload: lf->refs=%d\n", file->refs)); 443 lockmgr(&lock, LK_EXCLUSIVE, 0, curproc); 444 if (file->refs == 1) { 445 KLD_DPF(FILE, ("linker_file_unload: file is unloading, informing modules\n")); 446 /* 447 * Inform any modules associated with this file. 448 */ 449 for (mod = TAILQ_FIRST(&file->modules); mod; mod = next) { 450 next = module_getfnext(mod); 451 452 /* 453 * Give the module a chance to veto the unload. 454 */ 455 if ((error = module_unload(mod)) != 0) { 456 KLD_DPF(FILE, ("linker_file_unload: module %x vetoes unload\n", 457 mod)); 458 lockmgr(&lock, LK_RELEASE, 0, curproc); 459 goto out; 460 } 461 462 module_release(mod); 463 } 464 } 465 466 file->refs--; 467 if (file->refs > 0) { 468 lockmgr(&lock, LK_RELEASE, 0, curproc); 469 goto out; 470 } 471 472 for (ml = TAILQ_FIRST(&found_modules); ml; ml = nextml) { 473 nextml = TAILQ_NEXT(ml, link); 474 if (ml->container == file) { 475 TAILQ_REMOVE(&found_modules, ml, link); 476 } 477 } 478 479 /* Don't try to run SYSUNINITs if we are unloaded due to a link error */ 480 if (file->flags & LINKER_FILE_LINKED) { 481 linker_file_sysuninit(file); 482 linker_file_unregister_sysctls(file); 483 } 484 485 TAILQ_REMOVE(&linker_files, file, link); 486 lockmgr(&lock, LK_RELEASE, 0, curproc); 487 488 if (file->deps) { 489 for (i = 0; i < file->ndeps; i++) 490 linker_file_unload(file->deps[i]); 491 free(file->deps, M_LINKER); 492 file->deps = NULL; 493 } 494 495 for (cp = STAILQ_FIRST(&file->common); cp; 496 cp = STAILQ_FIRST(&file->common)) { 497 STAILQ_REMOVE(&file->common, cp, common_symbol, link); 498 free(cp, M_LINKER); 499 } 500 501 LINKER_UNLOAD(file); 502 if (file->filename) { 503 free(file->filename, M_LINKER); 504 file->filename = NULL; 505 } 506 kobj_delete((kobj_t) file, M_LINKER); 507 508out: 509 return error; 510} 511 512int 513linker_file_add_dependancy(linker_file_t file, linker_file_t dep) 514{ 515 linker_file_t* newdeps; 516 517 newdeps = malloc((file->ndeps + 1) * sizeof(linker_file_t*), 518 M_LINKER, M_WAITOK | M_ZERO); 519 if (newdeps == NULL) 520 return ENOMEM; 521 522 if (file->deps) { 523 bcopy(file->deps, newdeps, file->ndeps * sizeof(linker_file_t*)); 524 free(file->deps, M_LINKER); 525 } 526 file->deps = newdeps; 527 file->deps[file->ndeps] = dep; 528 file->ndeps++; 529 530 return 0; 531} 532 533caddr_t 534linker_file_lookup_symbol(linker_file_t file, const char* name, int deps) 535{ 536 c_linker_sym_t sym; 537 linker_symval_t symval; 538 caddr_t address; 539 size_t common_size = 0; 540 int i; 541 542 KLD_DPF(SYM, ("linker_file_lookup_symbol: file=%x, name=%s, deps=%d\n", 543 file, name, deps)); 544 545 if (LINKER_LOOKUP_SYMBOL(file, name, &sym) == 0) { 546 LINKER_SYMBOL_VALUES(file, sym, &symval); 547 if (symval.value == 0) 548 /* 549 * For commons, first look them up in the dependancies and 550 * only allocate space if not found there. 551 */ 552 common_size = symval.size; 553 else { 554 KLD_DPF(SYM, ("linker_file_lookup_symbol: symbol.value=%x\n", symval.value)); 555 return symval.value; 556 } 557 } 558 559 if (deps) { 560 for (i = 0; i < file->ndeps; i++) { 561 address = linker_file_lookup_symbol(file->deps[i], name, 0); 562 if (address) { 563 KLD_DPF(SYM, ("linker_file_lookup_symbol: deps value=%x\n", address)); 564 return address; 565 } 566 } 567 } 568 569 if (common_size > 0) { 570 /* 571 * This is a common symbol which was not found in the 572 * dependancies. We maintain a simple common symbol table in 573 * the file object. 574 */ 575 struct common_symbol* cp; 576 577 for (cp = STAILQ_FIRST(&file->common); cp; 578 cp = STAILQ_NEXT(cp, link)) 579 if (!strcmp(cp->name, name)) { 580 KLD_DPF(SYM, ("linker_file_lookup_symbol: old common value=%x\n", cp->address)); 581 return cp->address; 582 } 583 584 /* 585 * Round the symbol size up to align. 586 */ 587 common_size = (common_size + sizeof(int) - 1) & -sizeof(int); 588 cp = malloc(sizeof(struct common_symbol) 589 + common_size 590 + strlen(name) + 1, 591 M_LINKER, M_WAITOK | M_ZERO); 592 if (!cp) { 593 KLD_DPF(SYM, ("linker_file_lookup_symbol: nomem\n")); 594 return 0; 595 } 596 597 cp->address = (caddr_t) (cp + 1); 598 cp->name = cp->address + common_size; 599 strcpy(cp->name, name); 600 bzero(cp->address, common_size); 601 STAILQ_INSERT_TAIL(&file->common, cp, link); 602 603 KLD_DPF(SYM, ("linker_file_lookup_symbol: new common value=%x\n", cp->address)); 604 return cp->address; 605 } 606 607 KLD_DPF(SYM, ("linker_file_lookup_symbol: fail\n")); 608 return 0; 609} 610 611#ifdef DDB 612/* 613 * DDB Helpers. DDB has to look across multiple files with their own 614 * symbol tables and string tables. 615 * 616 * Note that we do not obey list locking protocols here. We really don't 617 * need DDB to hang because somebody's got the lock held. We'll take the 618 * chance that the files list is inconsistant instead. 619 */ 620 621int 622linker_ddb_lookup(const char *symstr, c_linker_sym_t *sym) 623{ 624 linker_file_t lf; 625 626 for (lf = TAILQ_FIRST(&linker_files); lf; lf = TAILQ_NEXT(lf, link)) { 627 if (LINKER_LOOKUP_SYMBOL(lf, symstr, sym) == 0) 628 return 0; 629 } 630 return ENOENT; 631} 632 633int 634linker_ddb_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp) 635{ 636 linker_file_t lf; 637 u_long off = (uintptr_t)value; 638 u_long diff, bestdiff; 639 c_linker_sym_t best; 640 c_linker_sym_t es; 641 642 best = 0; 643 bestdiff = off; 644 for (lf = TAILQ_FIRST(&linker_files); lf; lf = TAILQ_NEXT(lf, link)) { 645 if (LINKER_SEARCH_SYMBOL(lf, value, &es, &diff) != 0) 646 continue; 647 if (es != 0 && diff < bestdiff) { 648 best = es; 649 bestdiff = diff; 650 } 651 if (bestdiff == 0) 652 break; 653 } 654 if (best) { 655 *sym = best; 656 *diffp = bestdiff; 657 return 0; 658 } else { 659 *sym = 0; 660 *diffp = off; 661 return ENOENT; 662 } 663} 664 665int 666linker_ddb_symbol_values(c_linker_sym_t sym, linker_symval_t *symval) 667{ 668 linker_file_t lf; 669 670 for (lf = TAILQ_FIRST(&linker_files); lf; lf = TAILQ_NEXT(lf, link)) { 671 if (LINKER_SYMBOL_VALUES(lf, sym, symval) == 0) 672 return 0; 673 } 674 return ENOENT; 675} 676 677#endif 678 679/* 680 * Syscalls. 681 */ 682 683int 684kldload(struct proc* p, struct kldload_args* uap) 685{ 686 char* pathname, *realpath; 687 const char *filename; 688 linker_file_t lf; 689 int error = 0; 690 691 p->p_retval[0] = -1; 692 693 if (securelevel > 0) /* redundant, but that's OK */ 694 return EPERM; 695 696 if ((error = suser(p)) != 0) 697 return error; 698 699 realpath = NULL; 700 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 701 if ((error = copyinstr(SCARG(uap, file), pathname, MAXPATHLEN, NULL)) != 0) 702 goto out; 703 704 realpath = linker_search_path(pathname); 705 if (realpath == NULL) { 706 error = ENOENT; 707 goto out; 708 } 709 /* Can't load more than one file with the same name */ 710 filename = linker_basename(realpath); 711 if (linker_find_file_by_name(filename)) { 712 error = EEXIST; 713 goto out; 714 } 715 716 if ((error = linker_load_file(realpath, &lf)) != 0) 717 goto out; 718 719 lf->userrefs++; 720 p->p_retval[0] = lf->id; 721 722out: 723 if (pathname) 724 free(pathname, M_TEMP); 725 if (realpath) 726 free(realpath, M_LINKER); 727 return error; 728} 729 730int 731kldunload(struct proc* p, struct kldunload_args* uap) 732{ 733 linker_file_t lf; 734 int error = 0; 735 736 if (securelevel > 0) /* redundant, but that's OK */ 737 return EPERM; 738 739 if ((error = suser(p)) != 0) 740 return error; 741 742 lf = linker_find_file_by_id(SCARG(uap, fileid)); 743 if (lf) { 744 KLD_DPF(FILE, ("kldunload: lf->userrefs=%d\n", lf->userrefs)); 745 if (lf->userrefs == 0) { 746 printf("kldunload: attempt to unload file that was loaded by the kernel\n"); 747 error = EBUSY; 748 goto out; 749 } 750 lf->userrefs--; 751 error = linker_file_unload(lf); 752 if (error) 753 lf->userrefs++; 754 } else 755 error = ENOENT; 756 757out: 758 return error; 759} 760 761int 762kldfind(struct proc* p, struct kldfind_args* uap) 763{ 764 char* pathname; 765 const char *filename; 766 linker_file_t lf; 767 int error = 0; 768 769 p->p_retval[0] = -1; 770 771 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 772 if ((error = copyinstr(SCARG(uap, file), pathname, MAXPATHLEN, NULL)) != 0) 773 goto out; 774 775 filename = linker_basename(pathname); 776 777 lf = linker_find_file_by_name(filename); 778 if (lf) 779 p->p_retval[0] = lf->id; 780 else 781 error = ENOENT; 782 783out: 784 if (pathname) 785 free(pathname, M_TEMP); 786 return error; 787} 788 789int 790kldnext(struct proc* p, struct kldnext_args* uap) 791{ 792 linker_file_t lf; 793 int error = 0; 794 795 if (SCARG(uap, fileid) == 0) { 796 if (TAILQ_FIRST(&linker_files)) 797 p->p_retval[0] = TAILQ_FIRST(&linker_files)->id; 798 else 799 p->p_retval[0] = 0; 800 return 0; 801 } 802 803 lf = linker_find_file_by_id(SCARG(uap, fileid)); 804 if (lf) { 805 if (TAILQ_NEXT(lf, link)) 806 p->p_retval[0] = TAILQ_NEXT(lf, link)->id; 807 else 808 p->p_retval[0] = 0; 809 } else 810 error = ENOENT; 811 812 return error; 813} 814 815int 816kldstat(struct proc* p, struct kldstat_args* uap) 817{ 818 linker_file_t lf; 819 int error = 0; 820 int version; 821 struct kld_file_stat* stat; 822 int namelen; 823 824 lf = linker_find_file_by_id(SCARG(uap, fileid)); 825 if (!lf) { 826 error = ENOENT; 827 goto out; 828 } 829 830 stat = SCARG(uap, stat); 831 832 /* 833 * Check the version of the user's structure. 834 */ 835 if ((error = copyin(&stat->version, &version, sizeof(version))) != 0) 836 goto out; 837 if (version != sizeof(struct kld_file_stat)) { 838 error = EINVAL; 839 goto out; 840 } 841 842 namelen = strlen(lf->filename) + 1; 843 if (namelen > MAXPATHLEN) 844 namelen = MAXPATHLEN; 845 if ((error = copyout(lf->filename, &stat->name[0], namelen)) != 0) 846 goto out; 847 if ((error = copyout(&lf->refs, &stat->refs, sizeof(int))) != 0) 848 goto out; 849 if ((error = copyout(&lf->id, &stat->id, sizeof(int))) != 0) 850 goto out; 851 if ((error = copyout(&lf->address, &stat->address, sizeof(caddr_t))) != 0) 852 goto out; 853 if ((error = copyout(&lf->size, &stat->size, sizeof(size_t))) != 0) 854 goto out; 855 856 p->p_retval[0] = 0; 857 858out: 859 return error; 860} 861 862int 863kldfirstmod(struct proc* p, struct kldfirstmod_args* uap) 864{ 865 linker_file_t lf; 866 int error = 0; 867 868 lf = linker_find_file_by_id(SCARG(uap, fileid)); 869 if (lf) { 870 if (TAILQ_FIRST(&lf->modules)) 871 p->p_retval[0] = module_getid(TAILQ_FIRST(&lf->modules)); 872 else 873 p->p_retval[0] = 0; 874 } else 875 error = ENOENT; 876 877 return error; 878} 879 880int 881kldsym(struct proc *p, struct kldsym_args *uap) 882{ 883 char *symstr = NULL; 884 c_linker_sym_t sym; 885 linker_symval_t symval; 886 linker_file_t lf; 887 struct kld_sym_lookup lookup; 888 int error = 0; 889 890 if ((error = copyin(SCARG(uap, data), &lookup, sizeof(lookup))) != 0) 891 goto out; 892 if (lookup.version != sizeof(lookup) || SCARG(uap, cmd) != KLDSYM_LOOKUP) { 893 error = EINVAL; 894 goto out; 895 } 896 897 symstr = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 898 if ((error = copyinstr(lookup.symname, symstr, MAXPATHLEN, NULL)) != 0) 899 goto out; 900 901 if (SCARG(uap, fileid) != 0) { 902 lf = linker_find_file_by_id(SCARG(uap, fileid)); 903 if (lf == NULL) { 904 error = ENOENT; 905 goto out; 906 } 907 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 908 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 909 lookup.symvalue = (uintptr_t)symval.value; 910 lookup.symsize = symval.size; 911 error = copyout(&lookup, SCARG(uap, data), sizeof(lookup)); 912 } else 913 error = ENOENT; 914 } else { 915 for (lf = TAILQ_FIRST(&linker_files); lf; lf = TAILQ_NEXT(lf, link)) { 916 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 && 917 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) { 918 lookup.symvalue = (uintptr_t)symval.value; 919 lookup.symsize = symval.size; 920 error = copyout(&lookup, SCARG(uap, data), sizeof(lookup)); 921 break; 922 } 923 } 924 if (!lf) 925 error = ENOENT; 926 } 927out: 928 if (symstr) 929 free(symstr, M_TEMP); 930 return error; 931} 932 933/* 934 * Preloaded module support 935 */ 936 937static modlist_t 938modlist_lookup(const char *name) 939{ 940 modlist_t mod; 941 942 for (mod = TAILQ_FIRST(&found_modules); mod; mod = TAILQ_NEXT(mod, link)) { 943 if (!strcmp(mod->name, name)) 944 return mod; 945 } 946 return NULL; 947} 948 949/* 950 * This routine is cheap and nasty but will work for data pointers. 951 */ 952static void * 953linker_reloc_ptr(linker_file_t lf, void *offset) 954{ 955 return lf->address + (uintptr_t)offset; 956} 957 958static void 959linker_preload(void* arg) 960{ 961 caddr_t modptr; 962 char *modname, *nmodname; 963 char *modtype; 964 linker_file_t lf; 965 linker_class_t lc; 966 int error, mcount; 967 struct linker_set *sysinits; 968 linker_file_list_t loaded_files; 969 linker_file_list_t depended_files; 970 struct linker_set *deps; 971 struct mod_metadata *mp, *nmp; 972 int i, j; 973 int resolves; 974 modlist_t mod; 975 976 TAILQ_INIT(&loaded_files); 977 TAILQ_INIT(&depended_files); 978 TAILQ_INIT(&found_modules); 979 error = 0; 980 981 modptr = NULL; 982 while ((modptr = preload_search_next_name(modptr)) != NULL) { 983 modname = (char *)preload_search_info(modptr, MODINFO_NAME); 984 modtype = (char *)preload_search_info(modptr, MODINFO_TYPE); 985 if (modname == NULL) { 986 printf("Preloaded module at %p does not have a name!\n", modptr); 987 continue; 988 } 989 if (modtype == NULL) { 990 printf("Preloaded module at %p does not have a type!\n", modptr); 991 continue; 992 } 993 printf("Preloaded %s \"%s\" at %p.\n", modtype, modname, modptr); 994 lf = NULL; 995 for (lc = TAILQ_FIRST(&classes); lc; lc = TAILQ_NEXT(lc, link)) { 996 error = LINKER_LINK_PRELOAD(lc, modname, &lf); 997 if (error) { 998 lf = NULL; 999 break; 1000 } 1001 } 1002 if (lf) 1003 TAILQ_INSERT_TAIL(&loaded_files, lf, loaded); 1004 } 1005 1006 /* 1007 * First get a list of stuff in the kernel. 1008 */ 1009 deps = (struct linker_set*) 1010 linker_file_lookup_symbol(linker_kernel_file, MDT_SETNAME, 0); 1011 if (deps) { 1012 for (i = 0; i < deps->ls_length; i++) { 1013 mp = deps->ls_items[i]; 1014 if (mp->md_type != MDT_VERSION) 1015 continue; 1016 modname = mp->md_cval; 1017 if (modlist_lookup(modname) != NULL) { 1018 printf("module %s already present!\n", modname); 1019 /* XXX what can we do? this is a build error. :-( */ 1020 continue; 1021 } 1022 mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT|M_ZERO); 1023 if (mod == NULL) 1024 panic("no memory for module list"); 1025 mod->container = linker_kernel_file; 1026 mod->name = modname; 1027 TAILQ_INSERT_TAIL(&found_modules, mod, link); 1028 } 1029 } 1030 1031 /* 1032 * this is a once-off kinky bubble sort 1033 * resolve relocation dependency requirements 1034 */ 1035restart: 1036 for (lf = TAILQ_FIRST(&loaded_files); lf; lf = TAILQ_NEXT(lf, loaded)) { 1037 deps = (struct linker_set*) 1038 linker_file_lookup_symbol(lf, MDT_SETNAME, 0); 1039 /* 1040 * First, look to see if we would successfully link with this stuff. 1041 */ 1042 resolves = 1; /* unless we know otherwise */ 1043 if (deps) { 1044 for (i = 0; i < deps->ls_length; i++) { 1045 mp = linker_reloc_ptr(lf, deps->ls_items[i]); 1046 if (mp->md_type != MDT_DEPEND) 1047 continue; 1048 modname = linker_reloc_ptr(lf, mp->md_cval); 1049 for (j = 0; j < deps->ls_length; j++) { 1050 nmp = linker_reloc_ptr(lf, deps->ls_items[j]); 1051 if (nmp->md_type != MDT_VERSION) 1052 continue; 1053 nmodname = linker_reloc_ptr(lf, nmp->md_cval); 1054 if (strcmp(modname, nmodname) == 0) 1055 break; 1056 } 1057 if (j < deps->ls_length) /* it's a self reference */ 1058 continue; 1059 if (modlist_lookup(modname) == NULL) { 1060 /* ok, the module isn't here yet, we are not finished */ 1061 resolves = 0; 1062 } 1063 } 1064 } 1065 /* 1066 * OK, if we found our modules, we can link. So, "provide" the 1067 * modules inside and add it to the end of the link order list. 1068 */ 1069 if (resolves) { 1070 if (deps) { 1071 for (i = 0; i < deps->ls_length; i++) { 1072 mp = linker_reloc_ptr(lf, deps->ls_items[i]); 1073 if (mp->md_type != MDT_VERSION) 1074 continue; 1075 modname = linker_reloc_ptr(lf, mp->md_cval); 1076 if (modlist_lookup(modname) != NULL) { 1077 printf("module %s already present!\n", modname); 1078 linker_file_unload(lf); 1079 TAILQ_REMOVE(&loaded_files, lf, loaded); 1080 goto restart; /* we changed the tailq next ptr */ 1081 } 1082 mod = malloc(sizeof(struct modlist), M_LINKER, 1083 M_NOWAIT|M_ZERO); 1084 if (mod == NULL) 1085 panic("no memory for module list"); 1086 mod->container = lf; 1087 mod->name = modname; 1088 TAILQ_INSERT_TAIL(&found_modules, mod, link); 1089 } 1090 } 1091 TAILQ_REMOVE(&loaded_files, lf, loaded); 1092 TAILQ_INSERT_TAIL(&depended_files, lf, loaded); 1093 /* 1094 * Since we provided modules, we need to restart the sort so 1095 * that the previous files that depend on us have a chance. 1096 * Also, we've busted the tailq next pointer with the REMOVE. 1097 */ 1098 goto restart; 1099 } 1100 } 1101 1102 /* 1103 * At this point, we check to see what could not be resolved.. 1104 */ 1105 for (lf = TAILQ_FIRST(&loaded_files); lf; lf = TAILQ_NEXT(lf, loaded)) { 1106 printf("KLD file %s is missing dependencies\n", lf->filename); 1107 linker_file_unload(lf); 1108 TAILQ_REMOVE(&loaded_files, lf, loaded); 1109 } 1110 1111 /* 1112 * We made it. Finish off the linking in the order we determined. 1113 */ 1114 for (lf = TAILQ_FIRST(&depended_files); lf; lf = TAILQ_NEXT(lf, loaded)) { 1115 if (linker_kernel_file) { 1116 linker_kernel_file->refs++; 1117 error = linker_file_add_dependancy(lf, linker_kernel_file); 1118 if (error) 1119 panic("cannot add dependency"); 1120 } 1121 lf->userrefs++; /* so we can (try to) kldunload it */ 1122 deps = (struct linker_set*) 1123 linker_file_lookup_symbol(lf, MDT_SETNAME, 0); 1124 if (deps) { 1125 for (i = 0; i < deps->ls_length; i++) { 1126 mp = linker_reloc_ptr(lf, deps->ls_items[i]); 1127 if (mp->md_type != MDT_DEPEND) 1128 continue; 1129 modname = linker_reloc_ptr(lf, mp->md_cval); 1130 mod = modlist_lookup(modname); 1131 mod->container->refs++; 1132 error = linker_file_add_dependancy(lf, mod->container); 1133 if (error) 1134 panic("cannot add dependency"); 1135 } 1136 } 1137 1138 /* Now do relocation etc using the symbol search paths established by the dependencies */ 1139 error = LINKER_LINK_PRELOAD_FINISH(lf); 1140 if (error) { 1141 printf("KLD file %s - could not finalize loading\n", lf->filename); 1142 linker_file_unload(lf); 1143 continue; 1144 } 1145 1146 mcount = linker_file_register_modules(lf); 1147 sysinits = (struct linker_set*) 1148 linker_file_lookup_symbol(lf, "sysinit_set", 0); 1149 if (sysinits) 1150 sysinit_add((struct sysinit **)sysinits->ls_items); 1151 linker_file_register_sysctls(lf); 1152 lf->flags |= LINKER_FILE_LINKED; 1153 } 1154 /* woohoo! we made it! */ 1155} 1156 1157SYSINIT(preload, SI_SUB_KLD, SI_ORDER_MIDDLE, linker_preload, 0); 1158 1159/* 1160 * Search for a not-loaded module by name. 1161 * 1162 * Modules may be found in the following locations: 1163 * 1164 * - preloaded (result is just the module name) 1165 * - on disk (result is full path to module) 1166 * 1167 * If the module name is qualified in any way (contains path, etc.) 1168 * the we simply return a copy of it. 1169 * 1170 * The search path can be manipulated via sysctl. Note that we use the ';' 1171 * character as a separator to be consistent with the bootloader. 1172 */ 1173 1174static char def_linker_path[] = "/boot/modules/;/modules/;/boot/kernel/"; 1175static char linker_path[MAXPATHLEN] = ""; 1176 1177SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RW, linker_path, 1178 sizeof(linker_path), "module load search path"); 1179 1180TUNABLE_STR_DECL("module_path", def_linker_path, linker_path, 1181 sizeof(linker_path)); 1182 1183static char *linker_ext_list[] = { 1184 ".ko", 1185 "", 1186 NULL 1187}; 1188 1189static char * 1190linker_search_path(const char *name) 1191{ 1192 struct nameidata nd; 1193 struct proc *p = curproc; /* XXX */ 1194 char *cp, *ep, *result, **cpp; 1195 int error, extlen, len, flags; 1196 enum vtype type; 1197 1198 /* qualified at all? */ 1199 if (index(name, '/')) 1200 return(linker_strdup(name)); 1201 1202 extlen = 0; 1203 for (cpp = linker_ext_list; *cpp; cpp++) { 1204 len = strlen(*cpp); 1205 if (len > extlen) 1206 extlen = len; 1207 } 1208 extlen++; /* trailing '\0' */ 1209 1210 /* traverse the linker path */ 1211 cp = linker_path; 1212 len = strlen(name); 1213 for (;;) { 1214 1215 /* find the end of this component */ 1216 for (ep = cp; (*ep != 0) && (*ep != ';'); ep++) 1217 ; 1218 result = malloc((len + (ep - cp) + extlen + 1), M_LINKER, M_WAITOK); 1219 if (result == NULL) /* actually ENOMEM */ 1220 return(NULL); 1221 for (cpp = linker_ext_list; *cpp; cpp++) { 1222 strncpy(result, cp, ep - cp); 1223 strcpy(result + (ep - cp), "/"); 1224 strcat(result, name); 1225 strcat(result, *cpp); 1226 /* 1227 * Attempt to open the file, and return the path if we succeed 1228 * and it's a regular file. 1229 */ 1230 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, result, p); 1231 flags = FREAD; 1232 error = vn_open(&nd, &flags, 0); 1233 if (error == 0) { 1234 NDFREE(&nd, NDF_ONLY_PNBUF); 1235 type = nd.ni_vp->v_type; 1236 VOP_UNLOCK(nd.ni_vp, 0, p); 1237 vn_close(nd.ni_vp, FREAD, p->p_ucred, p); 1238 if (type == VREG) 1239 return(result); 1240 } 1241 } 1242 free(result, M_LINKER); 1243 1244 if (*ep == 0) 1245 break; 1246 cp = ep + 1; 1247 } 1248 return(NULL); 1249} 1250 1251static const char * 1252linker_basename(const char* path) 1253{ 1254 const char *filename; 1255 1256 filename = rindex(path, '/'); 1257 if (filename == NULL) 1258 return path; 1259 if (filename[1]) 1260 filename++; 1261 return filename; 1262} 1263 1264/* 1265 * Find a file which contains given module and load it, 1266 * if "parent" is not NULL, register a reference to it. 1267 */ 1268static int 1269linker_load_module(const char *modname, struct linker_file *parent) 1270{ 1271 linker_file_t lfdep; 1272 const char *filename; 1273 char *pathname; 1274 int error; 1275 1276 /* 1277 * There will be a system to look up or guess a file name from 1278 * a module name. 1279 * For now we just try to load a file with the same name. 1280 */ 1281 pathname = linker_search_path(modname); 1282 if (pathname == NULL) 1283 return ENOENT; 1284 1285 /* Can't load more than one file with the same basename */ 1286 filename = linker_basename(pathname); 1287 if (linker_find_file_by_name(filename)) { 1288 error = EEXIST; 1289 goto out; 1290 } 1291 1292 do { 1293 error = linker_load_file(pathname, &lfdep); 1294 if (error) 1295 break; 1296 if (parent) { 1297 error = linker_file_add_dependancy(parent, lfdep); 1298 if (error) 1299 break; 1300 } 1301 } while(0); 1302out: 1303 if (pathname) 1304 free(pathname, M_LINKER); 1305 return error; 1306} 1307 1308/* 1309 * This routine is responsible for finding dependencies of userland 1310 * initiated kldload(2)'s of files. 1311 */ 1312int 1313linker_load_dependancies(linker_file_t lf) 1314{ 1315 linker_file_t lfdep; 1316 struct linker_set *deps; 1317 struct mod_metadata *mp, *nmp; 1318 modlist_t mod; 1319 char *modname, *nmodname; 1320 int i, j, error = 0; 1321 1322 /* 1323 * All files are dependant on /kernel. 1324 */ 1325 if (linker_kernel_file) { 1326 linker_kernel_file->refs++; 1327 error = linker_file_add_dependancy(lf, linker_kernel_file); 1328 if (error) 1329 return error; 1330 } 1331 1332 deps = (struct linker_set*) 1333 linker_file_lookup_symbol(lf, MDT_SETNAME, 0); 1334 if (deps != NULL) { 1335 for (i = 0; i < deps->ls_length; i++) { 1336 mp = linker_reloc_ptr(lf, deps->ls_items[i]); 1337 if (mp->md_type != MDT_VERSION) 1338 continue; 1339 modname = linker_reloc_ptr(lf, mp->md_cval); 1340 if (modlist_lookup(modname) != NULL) { 1341 printf("module %s already present!\n", modname); 1342 return EEXIST; 1343 } 1344 } 1345 } 1346 if (deps != NULL) { 1347 for (i = 0; i < deps->ls_length; i++) { 1348 mp = linker_reloc_ptr(lf, deps->ls_items[i]); 1349 if (mp->md_type != MDT_DEPEND) 1350 continue; 1351 modname = linker_reloc_ptr(lf, mp->md_cval); 1352 nmodname = NULL; 1353 for (j = 0; j < deps->ls_length; j++) { 1354 nmp = linker_reloc_ptr(lf, deps->ls_items[j]); 1355 if (nmp->md_type != MDT_VERSION) 1356 continue; 1357 nmodname = linker_reloc_ptr(lf, nmp->md_cval); 1358 if (strcmp(modname, nmodname) == 0) 1359 break; 1360 } 1361 if (j < deps->ls_length) /* early exit, it's a self reference */ 1362 continue; 1363 mod = modlist_lookup(modname); 1364 if (mod) { /* woohoo, it's loaded already */ 1365 lfdep = mod->container; 1366 lfdep->refs++; 1367 error = linker_file_add_dependancy(lf, lfdep); 1368 if (error) 1369 break; 1370 continue; 1371 } 1372 error = linker_load_module(modname, lf); 1373 if (error) { 1374 printf("KLD %s: depends on %s - not available\n", 1375 lf->filename, modname); 1376 break; 1377 } 1378 } 1379 1380 } 1381 if (error == 0 && deps) { 1382 for (i = 0; i < deps->ls_length; i++) { 1383 mp = linker_reloc_ptr(lf, deps->ls_items[i]); 1384 if (mp->md_type != MDT_VERSION) 1385 continue; 1386 modname = linker_reloc_ptr(lf, mp->md_cval); 1387 mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT|M_ZERO); 1388 if (mod == NULL) 1389 panic("no memory for module list"); 1390 mod->container = lf; 1391 mod->name = modname; 1392 TAILQ_INSERT_TAIL(&found_modules, mod, link); 1393 } 1394 } 1395 return error; 1396} 1397