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 81937 2001-08-20 01:12:28Z dd $
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
57/* Metadata from the static kernel */
58SET_DECLARE(modmetadata_set, struct mod_metadata);
59
60MALLOC_DEFINE(M_LINKER, "linker", "kernel linker");
61
62linker_file_t linker_kernel_file;
63
64static struct lock lock; /* lock for the file list */
65static linker_class_list_t classes;
66static linker_file_list_t linker_files;
67static int next_file_id = 1;
68
69/* XXX wrong name; we're looking at version provision tags here, not modules */
70typedef TAILQ_HEAD(, modlist) modlisthead_t;
71struct modlist {
72 TAILQ_ENTRY(modlist) link; /* chain together all modules */
73 linker_file_t container;
74 const char *name;
75 int version;
76};
77typedef struct modlist *modlist_t;
78static modlisthead_t found_modules;
79
80static char *
81linker_strdup(const char *str)
82{
83 char *result;
84
85 if ((result = malloc((strlen(str) + 1), M_LINKER, M_WAITOK)) != NULL)
86 strcpy(result, str);
87 return(result);
88}
89
90static void
91linker_init(void* arg)
92{
93 lockinit(&lock, PVM, "klink", 0, 0);
94 TAILQ_INIT(&classes);
95 TAILQ_INIT(&linker_files);
96}
97
98SYSINIT(linker, SI_SUB_KLD, SI_ORDER_FIRST, linker_init, 0);
99
100int
101linker_add_class(linker_class_t lc)
102{
103 kobj_class_compile((kobj_class_t) lc);
104 TAILQ_INSERT_TAIL(&classes, lc, link);
105 return 0;
106}
107
108static void
109linker_file_sysinit(linker_file_t lf)
110{
111 struct sysinit** start, ** stop;
112 struct sysinit** sipp;
113 struct sysinit** xipp;
114 struct sysinit* save;
115
116 KLD_DPF(FILE, ("linker_file_sysinit: calling SYSINITs for %s\n",
117 lf->filename));
118
119 if (linker_file_lookup_set(lf, "sysinit_set", &start, &stop, NULL) != 0)
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 = start; sipp < stop; sipp++) {
129 for (xipp = sipp + 1; xipp < stop; 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 = start; sipp < stop; 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 sysinit** start, ** stop;
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 if (linker_file_lookup_set(lf, "sysuninit_set", &start, &stop, NULL) != 0)
166 return;
167
168 /*
169 * Perform a reverse bubble sort of the system initialization objects
170 * by their subsystem (primary key) and order (secondary key).
171 *
172 * Since some things care about execution order, this is the
173 * operation which ensures continued function.
174 */
175 for (sipp = start; sipp < stop; sipp++) {
176 for (xipp = sipp + 1; xipp < stop; xipp++) {
177 if ((*sipp)->subsystem > (*xipp)->subsystem ||
178 ((*sipp)->subsystem == (*xipp)->subsystem &&
179 (*sipp)->order >= (*xipp)->order))
180 continue; /* skip*/
181 save = *sipp;
182 *sipp = *xipp;
183 *xipp = save;
184 }
185 }
186
187 /*
188 * Traverse the (now) ordered list of system initialization tasks.
189 * Perform each task, and continue on to the next task.
190 */
191 for (sipp = start; sipp < stop; sipp++) {
192 if ((*sipp)->subsystem == SI_SUB_DUMMY)
193 continue; /* skip dummy task(s)*/
194
195 /* Call function */
196 (*((*sipp)->func))((*sipp)->udata);
197 }
198}
199
200static void
201linker_file_register_sysctls(linker_file_t lf)
202{
203 struct sysctl_oid **start, **stop, **oidp;
204
205 KLD_DPF(FILE, ("linker_file_register_sysctls: registering SYSCTLs for %s\n",
206 lf->filename));
207
208 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0)
209 return;
210
211 for (oidp = start; oidp < stop; oidp++)
212 sysctl_register_oid(*oidp);
213}
214
215static void
216linker_file_unregister_sysctls(linker_file_t lf)
217{
218 struct sysctl_oid **start, **stop, **oidp;
219
220 KLD_DPF(FILE, ("linker_file_unregister_sysctls: registering SYSCTLs for %s\n",
221 lf->filename));
222
223 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0)
224 return;
225
226 for (oidp = start; oidp < stop; oidp++)
227 sysctl_unregister_oid(*oidp);
228}
229
230static int
231linker_file_register_modules(linker_file_t lf)
232{
233 int error;
234 struct mod_metadata **start, **stop;
235 struct mod_metadata **mdp;
236 const moduledata_t *moddata;
237
238 KLD_DPF(FILE, ("linker_file_register_modules: registering modules in %s\n",
239 lf->filename));
240
241 if (linker_file_lookup_set(lf, "modmetadata_set", &start, &stop, 0) != 0) {
242 /*
243 * This fallback should be unnecessary, but if we get booted from
244 * boot2 instead of loader and we are missing our metadata then
245 * we have to try the best we can.
246 */
247 if (lf == linker_kernel_file) {
248 start = SET_BEGIN(modmetadata_set);
249 stop = SET_LIMIT(modmetadata_set);
250 } else {
251 return 0;
252 }
253 }
254 for (mdp = start; mdp < stop; mdp++) {
255 if ((*mdp)->md_type != MDT_MODULE)
256 continue;
257 moddata = (*mdp)->md_data;
258 KLD_DPF(FILE, ("Registering module %s in %s\n",
259 moddata->name, lf->filename));
260 if (module_lookupbyname(moddata->name) != NULL) {
261 printf("Warning: module %s already exists\n", moddata->name);
262 continue; /* or return a error ? */
263 }
264 error = module_register(moddata, lf);
265 if (error)
266 printf("Module %s failed to register: %d\n", moddata->name, error);
267 }
268 return 0;
269}
270
271static void
272linker_init_kernel_modules(void)
273{
274 linker_file_register_modules(linker_kernel_file);
275}
276
277SYSINIT(linker_kernel, SI_SUB_KLD, SI_ORDER_ANY, linker_init_kernel_modules, 0);
278
279int
280linker_load_file(const char* filename, linker_file_t* result)
281{
282 linker_class_t lc;
283 linker_file_t lf;
284 int foundfile, error = 0;
285
286 /* Refuse to load modules if securelevel raised */
287 if (securelevel > 0)
288 return EPERM;
289
290 lf = linker_find_file_by_name(filename);
291 if (lf) {
292 KLD_DPF(FILE, ("linker_load_file: file %s is already loaded, incrementing refs\n", filename));
293 *result = lf;
294 lf->refs++;
295 goto out;
296 }
297
298 lf = NULL;
299 foundfile = 0;
300 TAILQ_FOREACH(lc, &classes, link) {
301 KLD_DPF(FILE, ("linker_load_file: trying to load %s\n",
302 filename));
303 error = LINKER_LOAD_FILE(lc, filename, &lf);
304 /*
305 * If we got something other than ENOENT, then it exists but we cannot
306 * load it for some other reason.
307 */
308 if (error != ENOENT)
309 foundfile = 1;
310 if (lf) {
311 linker_file_register_modules(lf);
312 linker_file_register_sysctls(lf);
313 linker_file_sysinit(lf);
314 lf->flags |= LINKER_FILE_LINKED;
315
316 *result = lf;
317 error = 0;
318 goto out;
319 }
320 }
321 /*
322 * Less than ideal, but tells the user whether it failed to load or
323 * the module was not found.
324 */
325 if (foundfile)
326 error = ENOEXEC; /* Format not recognised (or unloadable) */
327 else
328 error = ENOENT; /* Nothing found */
329
330out:
331 return error;
332}
333
334int
335linker_reference_module(const char *modname, linker_file_t *result)
336{
337 char *pathname;
338 int res;
339
340 /*
341 * There will be a system to look up or guess a file name from
342 * a module name.
343 * For now we just try to load a file with the same name.
344 */
345 if ((pathname = linker_search_path(modname)) == NULL)
346 return (ENOENT);
347
348 /*
349 * If the module is already loaded or built into the kernel,
350 * linker_load_file() simply bumps it's refcount.
351 */
352 res = linker_load_file(pathname, result);
353
354 free(pathname, M_LINKER);
355
356 return (res);
357}
358
359linker_file_t
360linker_find_file_by_name(const char* filename)
361{
362 linker_file_t lf = 0;
363 char *koname;
364
365 koname = malloc(strlen(filename) + 4, M_LINKER, M_WAITOK);
366 if (koname == NULL)
367 goto out;
368 sprintf(koname, "%s.ko", filename);
369
370 lockmgr(&lock, LK_SHARED, 0, curproc);
371 TAILQ_FOREACH(lf, &linker_files, link) {
372 if (!strcmp(lf->filename, koname))
373 break;
374 if (!strcmp(lf->filename, filename))
375 break;
376 }
377 lockmgr(&lock, LK_RELEASE, 0, curproc);
378
379out:
380 if (koname)
381 free(koname, M_LINKER);
382 return lf;
383}
384
385linker_file_t
386linker_find_file_by_id(int fileid)
387{
388 linker_file_t lf = 0;
389
390 lockmgr(&lock, LK_SHARED, 0, curproc);
391 TAILQ_FOREACH(lf, &linker_files, link)
392 if (lf->id == fileid)
393 break;
394 lockmgr(&lock, LK_RELEASE, 0, curproc);
395
396 return lf;
397}
398
399linker_file_t
400linker_make_file(const char* pathname, linker_class_t lc)
401{
402 linker_file_t lf = 0;
403 const char *filename;
404
405 filename = linker_basename(pathname);
406
407 KLD_DPF(FILE, ("linker_make_file: new file, filename=%s\n", filename));
408 lockmgr(&lock, LK_EXCLUSIVE, 0, curproc);
409 lf = (linker_file_t) kobj_create((kobj_class_t) lc, M_LINKER, M_WAITOK);
410 if (!lf)
411 goto out;
412
413 lf->refs = 1;
414 lf->userrefs = 0;
415 lf->flags = 0;
416 lf->filename = linker_strdup(filename);
417 lf->id = next_file_id++;
418 lf->ndeps = 0;
419 lf->deps = NULL;
420 STAILQ_INIT(&lf->common);
421 TAILQ_INIT(&lf->modules);
422
423 TAILQ_INSERT_TAIL(&linker_files, lf, link);
424
425out:
426 lockmgr(&lock, LK_RELEASE, 0, curproc);
427 return lf;
428}
429
430int
431linker_file_unload(linker_file_t file)
432{
433 module_t mod, next;
434 modlist_t ml, nextml;
435 struct common_symbol* cp;
436 int error = 0;
437 int i;
438
439 /* Refuse to unload modules if securelevel raised */
440 if (securelevel > 0)
441 return EPERM;
442
443 KLD_DPF(FILE, ("linker_file_unload: lf->refs=%d\n", file->refs));
444 lockmgr(&lock, LK_EXCLUSIVE, 0, curproc);
445 if (file->refs == 1) {
446 KLD_DPF(FILE, ("linker_file_unload: file is unloading, informing modules\n"));
447 /*
448 * Inform any modules associated with this file.
449 */
450 for (mod = TAILQ_FIRST(&file->modules); mod; mod = next) {
451 next = module_getfnext(mod);
452
453 /*
454 * Give the module a chance to veto the unload.
455 */
456 if ((error = module_unload(mod)) != 0) {
457 KLD_DPF(FILE, ("linker_file_unload: module %x vetoes unload\n",
458 mod));
459 lockmgr(&lock, LK_RELEASE, 0, curproc);
460 goto out;
461 }
462
463 module_release(mod);
464 }
465 }
466
467 file->refs--;
468 if (file->refs > 0) {
469 lockmgr(&lock, LK_RELEASE, 0, curproc);
470 goto out;
471 }
472
473 for (ml = TAILQ_FIRST(&found_modules); ml; ml = nextml) {
474 nextml = TAILQ_NEXT(ml, link);
475 if (ml->container == file) {
476 TAILQ_REMOVE(&found_modules, ml, link);
477 }
478 }
479
480 /* Don't try to run SYSUNINITs if we are unloaded due to a link error */
481 if (file->flags & LINKER_FILE_LINKED) {
482 linker_file_sysuninit(file);
483 linker_file_unregister_sysctls(file);
484 }
485
486 TAILQ_REMOVE(&linker_files, file, link);
487 lockmgr(&lock, LK_RELEASE, 0, curproc);
488
489 if (file->deps) {
490 for (i = 0; i < file->ndeps; i++)
491 linker_file_unload(file->deps[i]);
492 free(file->deps, M_LINKER);
493 file->deps = NULL;
494 }
495
496 for (cp = STAILQ_FIRST(&file->common); cp;
497 cp = STAILQ_FIRST(&file->common)) {
498 STAILQ_REMOVE(&file->common, cp, common_symbol, link);
499 free(cp, M_LINKER);
500 }
501
502 LINKER_UNLOAD(file);
503 if (file->filename) {
504 free(file->filename, M_LINKER);
505 file->filename = NULL;
506 }
507 kobj_delete((kobj_t) file, M_LINKER);
508
509out:
510 return error;
511}
512
513int
514linker_file_add_dependancy(linker_file_t file, linker_file_t dep)
515{
516 linker_file_t* newdeps;
517
518 newdeps = malloc((file->ndeps + 1) * sizeof(linker_file_t*),
519 M_LINKER, M_WAITOK | M_ZERO);
520 if (newdeps == NULL)
521 return ENOMEM;
522
523 if (file->deps) {
524 bcopy(file->deps, newdeps, file->ndeps * sizeof(linker_file_t*));
525 free(file->deps, M_LINKER);
526 }
527 file->deps = newdeps;
528 file->deps[file->ndeps] = dep;
529 file->ndeps++;
530
531 return 0;
532}
533
534/*
535 * Locate a linker set and its contents.
536 * This is a helper function to avoid linker_if.h exposure elsewhere.
537 * Note: firstp and lastp are really void ***
538 */
539int
540linker_file_lookup_set(linker_file_t file, const char *name,
541 void *firstp, void *lastp, int *countp)
542{
543
544 return LINKER_LOOKUP_SET(file, name, firstp, lastp, countp);
545}
546
547caddr_t
548linker_file_lookup_symbol(linker_file_t file, const char* name, int deps)
549{
550 c_linker_sym_t sym;
551 linker_symval_t symval;
552 caddr_t address;
553 size_t common_size = 0;
554 int i;
555
556 KLD_DPF(SYM, ("linker_file_lookup_symbol: file=%x, name=%s, deps=%d\n",
557 file, name, deps));
558
559 if (LINKER_LOOKUP_SYMBOL(file, name, &sym) == 0) {
560 LINKER_SYMBOL_VALUES(file, sym, &symval);
561 if (symval.value == 0)
562 /*
563 * For commons, first look them up in the dependancies and
564 * only allocate space if not found there.
565 */
566 common_size = symval.size;
567 else {
568 KLD_DPF(SYM, ("linker_file_lookup_symbol: symbol.value=%x\n", symval.value));
569 return symval.value;
570 }
571 }
572
573 if (deps) {
574 for (i = 0; i < file->ndeps; i++) {
575 address = linker_file_lookup_symbol(file->deps[i], name, 0);
576 if (address) {
577 KLD_DPF(SYM, ("linker_file_lookup_symbol: deps value=%x\n", address));
578 return address;
579 }
580 }
581 }
582
583 if (common_size > 0) {
584 /*
585 * This is a common symbol which was not found in the
586 * dependancies. We maintain a simple common symbol table in
587 * the file object.
588 */
589 struct common_symbol* cp;
590
591 STAILQ_FOREACH(cp, &file->common, link)
592 if (!strcmp(cp->name, name)) {
593 KLD_DPF(SYM, ("linker_file_lookup_symbol: old common value=%x\n", cp->address));
594 return cp->address;
595 }
596
597 /*
598 * Round the symbol size up to align.
599 */
600 common_size = (common_size + sizeof(int) - 1) & -sizeof(int);
601 cp = malloc(sizeof(struct common_symbol)
602 + common_size
603 + strlen(name) + 1,
604 M_LINKER, M_WAITOK | M_ZERO);
605 if (!cp) {
606 KLD_DPF(SYM, ("linker_file_lookup_symbol: nomem\n"));
607 return 0;
608 }
609
610 cp->address = (caddr_t) (cp + 1);
611 cp->name = cp->address + common_size;
612 strcpy(cp->name, name);
613 bzero(cp->address, common_size);
614 STAILQ_INSERT_TAIL(&file->common, cp, link);
615
616 KLD_DPF(SYM, ("linker_file_lookup_symbol: new common value=%x\n", cp->address));
617 return cp->address;
618 }
619
620 KLD_DPF(SYM, ("linker_file_lookup_symbol: fail\n"));
621 return 0;
622}
623
624#ifdef DDB
625/*
626 * DDB Helpers. DDB has to look across multiple files with their own
627 * symbol tables and string tables.
628 *
629 * Note that we do not obey list locking protocols here. We really don't
630 * need DDB to hang because somebody's got the lock held. We'll take the
631 * chance that the files list is inconsistant instead.
632 */
633
634int
635linker_ddb_lookup(const char *symstr, c_linker_sym_t *sym)
636{
637 linker_file_t lf;
638
639 TAILQ_FOREACH(lf, &linker_files, link) {
640 if (LINKER_LOOKUP_SYMBOL(lf, symstr, sym) == 0)
641 return 0;
642 }
643 return ENOENT;
644}
645
646int
647linker_ddb_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp)
648{
649 linker_file_t lf;
650 u_long off = (uintptr_t)value;
651 u_long diff, bestdiff;
652 c_linker_sym_t best;
653 c_linker_sym_t es;
654
655 best = 0;
656 bestdiff = off;
657 TAILQ_FOREACH(lf, &linker_files, link) {
658 if (LINKER_SEARCH_SYMBOL(lf, value, &es, &diff) != 0)
659 continue;
660 if (es != 0 && diff < bestdiff) {
661 best = es;
662 bestdiff = diff;
663 }
664 if (bestdiff == 0)
665 break;
666 }
667 if (best) {
668 *sym = best;
669 *diffp = bestdiff;
670 return 0;
671 } else {
672 *sym = 0;
673 *diffp = off;
674 return ENOENT;
675 }
676}
677
678int
679linker_ddb_symbol_values(c_linker_sym_t sym, linker_symval_t *symval)
680{
681 linker_file_t lf;
682
683 TAILQ_FOREACH(lf, &linker_files, link) {
684 if (LINKER_SYMBOL_VALUES(lf, sym, symval) == 0)
685 return 0;
686 }
687 return ENOENT;
688}
689
690#endif
691
692/*
693 * Syscalls.
694 */
695
696int
697kldload(struct proc* p, struct kldload_args* uap)
698{
699 char* pathname, *realpath;
700 const char *filename;
701 linker_file_t lf;
702 int error = 0;
703
704 p->p_retval[0] = -1;
705
706 if (securelevel > 0) /* redundant, but that's OK */
707 return EPERM;
708
709 if ((error = suser(p)) != 0)
710 return error;
711
712 realpath = NULL;
713 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
714 if ((error = copyinstr(SCARG(uap, file), pathname, MAXPATHLEN, NULL)) != 0)
715 goto out;
716
717 realpath = linker_search_path(pathname);
718 if (realpath == NULL) {
719 error = ENOENT;
720 goto out;
721 }
722 /* Can't load more than one file with the same name */
723 filename = linker_basename(realpath);
724 if (linker_find_file_by_name(filename)) {
725 error = EEXIST;
726 goto out;
727 }
728
729 if ((error = linker_load_file(realpath, &lf)) != 0)
730 goto out;
731
732 lf->userrefs++;
733 p->p_retval[0] = lf->id;
734
735out:
736 if (pathname)
737 free(pathname, M_TEMP);
738 if (realpath)
739 free(realpath, M_LINKER);
740 return error;
741}
742
743int
744kldunload(struct proc* p, struct kldunload_args* uap)
745{
746 linker_file_t lf;
747 int error = 0;
748
749 if (securelevel > 0) /* redundant, but that's OK */
750 return EPERM;
751
752 if ((error = suser(p)) != 0)
753 return error;
754
755 lf = linker_find_file_by_id(SCARG(uap, fileid));
756 if (lf) {
757 KLD_DPF(FILE, ("kldunload: lf->userrefs=%d\n", lf->userrefs));
758 if (lf->userrefs == 0) {
759 printf("kldunload: attempt to unload file that was loaded by the kernel\n");
760 error = EBUSY;
761 goto out;
762 }
763 lf->userrefs--;
764 error = linker_file_unload(lf);
765 if (error)
766 lf->userrefs++;
767 } else
768 error = ENOENT;
769
770out:
771 return error;
772}
773
774int
775kldfind(struct proc* p, struct kldfind_args* uap)
776{
777 char* pathname;
778 const char *filename;
779 linker_file_t lf;
780 int error = 0;
781
782 p->p_retval[0] = -1;
783
784 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
785 if ((error = copyinstr(SCARG(uap, file), pathname, MAXPATHLEN, NULL)) != 0)
786 goto out;
787
788 filename = linker_basename(pathname);
789
790 lf = linker_find_file_by_name(filename);
791 if (lf)
792 p->p_retval[0] = lf->id;
793 else
794 error = ENOENT;
795
796out:
797 if (pathname)
798 free(pathname, M_TEMP);
799 return error;
800}
801
802int
803kldnext(struct proc* p, struct kldnext_args* uap)
804{
805 linker_file_t lf;
806 int error = 0;
807
808 if (SCARG(uap, fileid) == 0) {
809 if (TAILQ_FIRST(&linker_files))
810 p->p_retval[0] = TAILQ_FIRST(&linker_files)->id;
811 else
812 p->p_retval[0] = 0;
813 return 0;
814 }
815
816 lf = linker_find_file_by_id(SCARG(uap, fileid));
817 if (lf) {
818 if (TAILQ_NEXT(lf, link))
819 p->p_retval[0] = TAILQ_NEXT(lf, link)->id;
820 else
821 p->p_retval[0] = 0;
822 } else
823 error = ENOENT;
824
825 return error;
826}
827
828int
829kldstat(struct proc* p, struct kldstat_args* uap)
830{
831 linker_file_t lf;
832 int error = 0;
833 int version;
834 struct kld_file_stat* stat;
835 int namelen;
836
837 lf = linker_find_file_by_id(SCARG(uap, fileid));
838 if (!lf) {
839 error = ENOENT;
840 goto out;
841 }
842
843 stat = SCARG(uap, stat);
844
845 /*
846 * Check the version of the user's structure.
847 */
848 if ((error = copyin(&stat->version, &version, sizeof(version))) != 0)
849 goto out;
850 if (version != sizeof(struct kld_file_stat)) {
851 error = EINVAL;
852 goto out;
853 }
854
855 namelen = strlen(lf->filename) + 1;
856 if (namelen > MAXPATHLEN)
857 namelen = MAXPATHLEN;
858 if ((error = copyout(lf->filename, &stat->name[0], namelen)) != 0)
859 goto out;
860 if ((error = copyout(&lf->refs, &stat->refs, sizeof(int))) != 0)
861 goto out;
862 if ((error = copyout(&lf->id, &stat->id, sizeof(int))) != 0)
863 goto out;
864 if ((error = copyout(&lf->address, &stat->address, sizeof(caddr_t))) != 0)
865 goto out;
866 if ((error = copyout(&lf->size, &stat->size, sizeof(size_t))) != 0)
867 goto out;
868
869 p->p_retval[0] = 0;
870
871out:
872 return error;
873}
874
875int
876kldfirstmod(struct proc* p, struct kldfirstmod_args* uap)
877{
878 linker_file_t lf;
879 int error = 0;
880
881 lf = linker_find_file_by_id(SCARG(uap, fileid));
882 if (lf) {
883 if (TAILQ_FIRST(&lf->modules))
884 p->p_retval[0] = module_getid(TAILQ_FIRST(&lf->modules));
885 else
886 p->p_retval[0] = 0;
887 } else
888 error = ENOENT;
889
890 return error;
891}
892
893int
894kldsym(struct proc *p, struct kldsym_args *uap)
895{
896 char *symstr = NULL;
897 c_linker_sym_t sym;
898 linker_symval_t symval;
899 linker_file_t lf;
900 struct kld_sym_lookup lookup;
901 int error = 0;
902
903 if ((error = copyin(SCARG(uap, data), &lookup, sizeof(lookup))) != 0)
904 goto out;
905 if (lookup.version != sizeof(lookup) || SCARG(uap, cmd) != KLDSYM_LOOKUP) {
906 error = EINVAL;
907 goto out;
908 }
909
910 symstr = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
911 if ((error = copyinstr(lookup.symname, symstr, MAXPATHLEN, NULL)) != 0)
912 goto out;
913
914 if (SCARG(uap, fileid) != 0) {
915 lf = linker_find_file_by_id(SCARG(uap, fileid));
916 if (lf == NULL) {
917 error = ENOENT;
918 goto out;
919 }
920 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 &&
921 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) {
922 lookup.symvalue = (uintptr_t)symval.value;
923 lookup.symsize = symval.size;
924 error = copyout(&lookup, SCARG(uap, data), sizeof(lookup));
925 } else
926 error = ENOENT;
927 } else {
928 TAILQ_FOREACH(lf, &linker_files, link) {
929 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 &&
930 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) {
931 lookup.symvalue = (uintptr_t)symval.value;
932 lookup.symsize = symval.size;
933 error = copyout(&lookup, SCARG(uap, data), sizeof(lookup));
934 break;
935 }
936 }
937 if (!lf)
938 error = ENOENT;
939 }
940out:
941 if (symstr)
942 free(symstr, M_TEMP);
943 return error;
944}
945
946/*
947 * Preloaded module support
948 */
949
950static modlist_t
951modlist_lookup(const char *name, int ver)
952{
953 modlist_t mod;
954
955 TAILQ_FOREACH(mod, &found_modules, link) {
956 if (strcmp(mod->name, name) == 0 && (ver == 0 || mod->version == ver))
957 return mod;
958 }
959 return NULL;
960}
961
962static modlist_t
963modlist_newmodule(const char *modname, int version, linker_file_t container)
964{
965 modlist_t mod;
966
967 mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT);
968 if (mod == NULL)
969 panic("no memory for module list");
970 bzero(mod, sizeof(*mod));
971 mod->container = container;
972 mod->name = modname;
973 mod->version = version;
974 TAILQ_INSERT_TAIL(&found_modules, mod, link);
975 return mod;
976}
977
978/*
979 * This routine is cheap and nasty but will work for data pointers.
980 */
981static void *
982linker_reloc_ptr(linker_file_t lf, const void *offset)
983{
984 return lf->address + (uintptr_t)offset;
985}
986
987/*
988 * Dereference MDT_VERSION metadata into module name and version
989 */
990static void
991linker_mdt_version(linker_file_t lf, struct mod_metadata *mp,
992 const char **modname, int *version)
993{
994 struct mod_version *mvp;
995
996 if (modname)
997 *modname = linker_reloc_ptr(lf, mp->md_cval);
998 if (version) {
999 mvp = linker_reloc_ptr(lf, mp->md_data);
1000 *version = mvp->mv_version;
1001 }
1002}
1003
1004/*
1005 * Dereference MDT_DEPEND metadata into module name and mod_depend structure
1006 */
1007static void
1008linker_mdt_depend(linker_file_t lf, struct mod_metadata *mp,
1009 const char **modname, struct mod_depend **verinfo)
1010{
1011
1012 if (modname)
1013 *modname = linker_reloc_ptr(lf, mp->md_cval);
1014 if (verinfo)
1015 *verinfo = linker_reloc_ptr(lf, mp->md_data);
1016}
1017
1018static void
1019linker_addmodules(linker_file_t lf, struct mod_metadata **start,
1020 struct mod_metadata **stop, int preload)
1021{
1022 struct mod_metadata *mp, **mdp;
1023 const char *modname;
1024 int ver;
1025
1026 for (mdp = start; mdp < stop; mdp++) {
1027 if (preload)
1028 mp = *mdp;
1029 else
1030 mp = linker_reloc_ptr(lf, *mdp);
1031 if (mp->md_type != MDT_VERSION)
1032 continue;
1033 if (preload) {
1034 modname = mp->md_cval;
1035 ver = ((struct mod_version*)mp->md_data)->mv_version;
1036 } else
1037 linker_mdt_version(lf, mp, &modname, &ver);
1038 if (modlist_lookup(modname, ver) != NULL) {
1039 printf("module %s already present!\n", modname);
1040 /* XXX what can we do? this is a build error. :-( */
1041 continue;
1042 }
1043 modlist_newmodule(modname, ver, lf);
1044 }
1045}
1046
1047static void
1048linker_preload(void* arg)
1049{
1050 caddr_t modptr;
1051 const char *modname, *nmodname;
1052 char *modtype;
1053 linker_file_t lf;
1054 linker_class_t lc;
1055 int error;
1056 linker_file_list_t loaded_files;
1057 linker_file_list_t depended_files;
1058 struct mod_metadata *mp, *nmp;
1059 struct mod_metadata **start, **stop, **mdp, **nmdp;
1060 struct mod_depend *verinfo;
1061 int nver;
1062 int resolves;
1063 modlist_t mod;
1064 struct sysinit **si_start, **si_stop;
1065
1066 TAILQ_INIT(&loaded_files);
1067 TAILQ_INIT(&depended_files);
1068 TAILQ_INIT(&found_modules);
1069 error = 0;
1070
1071 modptr = NULL;
1072 while ((modptr = preload_search_next_name(modptr)) != NULL) {
1073 modname = (char *)preload_search_info(modptr, MODINFO_NAME);
1074 modtype = (char *)preload_search_info(modptr, MODINFO_TYPE);
1075 if (modname == NULL) {
1076 printf("Preloaded module at %p does not have a name!\n", modptr);
1077 continue;
1078 }
1079 if (modtype == NULL) {
1080 printf("Preloaded module at %p does not have a type!\n", modptr);
1081 continue;
1082 }
1083 printf("Preloaded %s \"%s\" at %p.\n", modtype, modname, modptr);
1084 lf = NULL;
1085 TAILQ_FOREACH(lc, &classes, link) {
1086 error = LINKER_LINK_PRELOAD(lc, modname, &lf);
1087 if (error) {
1088 lf = NULL;
1089 break;
1090 }
1091 }
1092 if (lf)
1093 TAILQ_INSERT_TAIL(&loaded_files, lf, loaded);
1094 }
1095
1096 /*
1097 * First get a list of stuff in the kernel.
1098 */
1099 if (linker_file_lookup_set(linker_kernel_file, MDT_SETNAME, &start, &stop,
1100 NULL) == 0)
1101 linker_addmodules(linker_kernel_file, start, stop, 1);
1102
1103 /*
1104 * this is a once-off kinky bubble sort
1105 * resolve relocation dependency requirements
1106 */
1107restart:
1108 TAILQ_FOREACH(lf, &loaded_files, loaded) {
1109 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop, NULL);
1110 /*
1111 * First, look to see if we would successfully link with this stuff.
1112 */
1113 resolves = 1; /* unless we know otherwise */
1114 if (!error) {
1115 for (mdp = start; mdp < stop; mdp++) {
1116 mp = linker_reloc_ptr(lf, *mdp);
1117 if (mp->md_type != MDT_DEPEND)
1118 continue;
1119 linker_mdt_depend(lf, mp, &modname, &verinfo);
1120 for (nmdp = start; nmdp < stop; nmdp++) {
1121 nmp = linker_reloc_ptr(lf, *nmdp);
1122 if (nmp->md_type != MDT_VERSION)
1123 continue;
1124 linker_mdt_version(lf, nmp, &nmodname, NULL);
1125 nmodname = linker_reloc_ptr(lf, nmp->md_cval);
1126 if (strcmp(modname, nmodname) == 0)
1127 break;
1128 }
1129 if (nmdp < stop) /* it's a self reference */
1130 continue;
1131 if (modlist_lookup(modname, 0) == NULL) {
1132 /* ok, the module isn't here yet, we are not finished */
1133 resolves = 0;
1134 }
1135 }
1136 }
1137 /*
1138 * OK, if we found our modules, we can link. So, "provide" the
1139 * modules inside and add it to the end of the link order list.
1140 */
1141 if (resolves) {
1142 if (!error) {
1143 for (mdp = start; mdp < stop; mdp++) {
1144 mp = linker_reloc_ptr(lf, *mdp);
1145 if (mp->md_type != MDT_VERSION)
1146 continue;
1147 linker_mdt_version(lf, mp, &modname, &nver);
1148 if (modlist_lookup(modname, nver) != NULL) {
1149 printf("module %s already present!\n", modname);
1150 linker_file_unload(lf);
1151 TAILQ_REMOVE(&loaded_files, lf, loaded);
1152 goto restart; /* we changed the tailq next ptr */
1153 }
1154 modlist_newmodule(modname, nver, lf);
1155 }
1156 }
1157 TAILQ_REMOVE(&loaded_files, lf, loaded);
1158 TAILQ_INSERT_TAIL(&depended_files, lf, loaded);
1159 /*
1160 * Since we provided modules, we need to restart the sort so
1161 * that the previous files that depend on us have a chance.
1162 * Also, we've busted the tailq next pointer with the REMOVE.
1163 */
1164 goto restart;
1165 }
1166 }
1167
1168 /*
1169 * At this point, we check to see what could not be resolved..
1170 */
1171 TAILQ_FOREACH(lf, &loaded_files, loaded) {
1172 printf("KLD file %s is missing dependencies\n", lf->filename);
1173 linker_file_unload(lf);
1174 TAILQ_REMOVE(&loaded_files, lf, loaded);
1175 }
1176
1177 /*
1178 * We made it. Finish off the linking in the order we determined.
1179 */
1180 TAILQ_FOREACH(lf, &depended_files, loaded) {
1181 if (linker_kernel_file) {
1182 linker_kernel_file->refs++;
1183 error = linker_file_add_dependancy(lf, linker_kernel_file);
1184 if (error)
1185 panic("cannot add dependency");
1186 }
1187 lf->userrefs++; /* so we can (try to) kldunload it */
1188 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop, NULL);
1189 if (!error) {
1190 for (mdp = start; mdp < stop; mdp++) {
1191 mp = linker_reloc_ptr(lf, *mdp);
1192 if (mp->md_type != MDT_DEPEND)
1193 continue;
1194 linker_mdt_depend(lf, mp, &modname, &verinfo);
1195 mod = modlist_lookup(modname, 0);
1196 mod->container->refs++;
1197 error = linker_file_add_dependancy(lf, mod->container);
1198 if (error)
1199 panic("cannot add dependency");
1200 }
1201 }
1202
1203 /*
1204 * Now do relocation etc using the symbol search paths established by
1205 * the dependencies
1206 */
1207 error = LINKER_LINK_PRELOAD_FINISH(lf);
1208 if (error) {
1209 printf("KLD file %s - could not finalize loading\n", lf->filename);
1210 linker_file_unload(lf);
1211 continue;
1212 }
1213
1214 linker_file_register_modules(lf);
1215 if (linker_file_lookup_set(lf, "sysinit_set", &si_start, &si_stop, NULL) == 0)
1216 sysinit_add(si_start, si_stop);
1217 linker_file_register_sysctls(lf);
1218 lf->flags |= LINKER_FILE_LINKED;
1219 }
1220 /* woohoo! we made it! */
1221}
1222
1223SYSINIT(preload, SI_SUB_KLD, SI_ORDER_MIDDLE, linker_preload, 0);
1224
1225/*
1226 * Search for a not-loaded module by name.
1227 *
1228 * Modules may be found in the following locations:
1229 *
1230 * - preloaded (result is just the module name)
1231 * - on disk (result is full path to module)
1232 *
1233 * If the module name is qualified in any way (contains path, etc.)
1234 * the we simply return a copy of it.
1235 *
1236 * The search path can be manipulated via sysctl. Note that we use the ';'
1237 * character as a separator to be consistent with the bootloader.
1238 */
1239
1240static char linker_path[MAXPATHLEN] = "/boot/kernel;/boot/modules/;/modules/";
1241
1242SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RW, linker_path,
1243 sizeof(linker_path), "module load search path");
1244
1245TUNABLE_STR("module_path", linker_path, sizeof(linker_path));
1246
1247static char *linker_ext_list[] = {
1248 ".ko",
1249 "",
1250 NULL
1251};
1252
1253static char *
1254linker_search_path(const char *name)
1255{
1256 struct nameidata nd;
1257 struct proc *p = curproc; /* XXX */
1258 char *cp, *ep, *result, **cpp;
1259 int error, extlen, len, flags;
1260 enum vtype type;
1261
1262 /* qualified at all? */
1263 if (index(name, '/'))
1264 return(linker_strdup(name));
1265
1266 extlen = 0;
1267 for (cpp = linker_ext_list; *cpp; cpp++) {
1268 len = strlen(*cpp);
1269 if (len > extlen)
1270 extlen = len;
1271 }
1272 extlen++; /* trailing '\0' */
1273
1274 /* traverse the linker path */
1275 cp = linker_path;
1276 len = strlen(name);
1277 for (;;) {
1278
1279 /* find the end of this component */
1280 for (ep = cp; (*ep != 0) && (*ep != ';'); ep++)
1281 ;
1282 result = malloc((len + (ep - cp) + extlen + 1), M_LINKER, M_WAITOK);
1283 if (result == NULL) /* actually ENOMEM */
1284 return(NULL);
1285 for (cpp = linker_ext_list; *cpp; cpp++) {
1286 strncpy(result, cp, ep - cp);
1287 strcpy(result + (ep - cp), "/");
1288 strcat(result, name);
1289 strcat(result, *cpp);
1290 /*
1291 * Attempt to open the file, and return the path if we succeed
1292 * and it's a regular file.
1293 */
1294 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, result, p);
1295 flags = FREAD;
1296 error = vn_open(&nd, &flags, 0);
1297 if (error == 0) {
1298 NDFREE(&nd, NDF_ONLY_PNBUF);
1299 type = nd.ni_vp->v_type;
1300 VOP_UNLOCK(nd.ni_vp, 0, p);
1301 vn_close(nd.ni_vp, FREAD, p->p_ucred, p);
1302 if (type == VREG)
1303 return(result);
1304 }
1305 }
1306 free(result, M_LINKER);
1307
1308 if (*ep == 0)
1309 break;
1310 cp = ep + 1;
1311 }
1312 return(NULL);
1313}
1314
1315static const char *
1316linker_basename(const char* path)
1317{
1318 const char *filename;
1319
1320 filename = rindex(path, '/');
1321 if (filename == NULL)
1322 return path;
1323 if (filename[1])
1324 filename++;
1325 return filename;
1326}
1327
1328/*
1329 * Find a file which contains given module and load it,
1330 * if "parent" is not NULL, register a reference to it.
1331 */
1332static int
1333linker_load_module(const char *modname, struct linker_file *parent)
1334{
1335 linker_file_t lfdep;
1336 const char *filename;
1337 char *pathname;
1338 int error;
1339
1340 /*
1341 * There will be a system to look up or guess a file name from
1342 * a module name.
1343 * For now we just try to load a file with the same name.
1344 */
1345 pathname = linker_search_path(modname);
1346 if (pathname == NULL)
1347 return ENOENT;
1348
1349 /* Can't load more than one file with the same basename */
1350 filename = linker_basename(pathname);
1351 if (linker_find_file_by_name(filename)) {
1352 error = EEXIST;
1353 goto out;
1354 }
1355
1356 do {
1357 error = linker_load_file(pathname, &lfdep);
1358 if (error)
1359 break;
1360 if (parent) {
1361 error = linker_file_add_dependancy(parent, lfdep);
1362 if (error)
1363 break;
1364 }
1365 } while(0);
1366out:
1367 if (pathname)
1368 free(pathname, M_LINKER);
1369 return error;
1370}
1371
1372/*
1373 * This routine is responsible for finding dependencies of userland
1374 * initiated kldload(2)'s of files.
1375 */
1376int
1377linker_load_dependancies(linker_file_t lf)
1378{
1379 linker_file_t lfdep;
1380 struct mod_metadata **start, **stop, **mdp, **nmdp;
1381 struct mod_metadata *mp, *nmp;
1382 modlist_t mod;
1383 const char *modname, *nmodname;
1384 int ver, error = 0, count;
1385
1386 /*
1387 * All files are dependant on /kernel.
1388 */
1389 if (linker_kernel_file) {
1390 linker_kernel_file->refs++;
1391 error = linker_file_add_dependancy(lf, linker_kernel_file);
1392 if (error)
1393 return error;
1394 }
1395
1396 if (linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop, &count) != 0)
1397 return 0;
1398 for (mdp = start; mdp < stop; mdp++) {
1399 mp = linker_reloc_ptr(lf, *mdp);
1400 if (mp->md_type != MDT_VERSION)
1401 continue;
1402 linker_mdt_version(lf, mp, &modname, &ver);
1403 mod = modlist_lookup(modname, ver);
1404 if (mod != NULL) {
1405 printf("interface %s.%d already present in the KLD '%s'!\n",
1406 modname, ver, mod->container->filename);
1407 return EEXIST;
1408 }
1409 }
1410
1411 for (mdp = start; mdp < stop; mdp++) {
1412 mp = linker_reloc_ptr(lf, *mdp);
1413 if (mp->md_type != MDT_DEPEND)
1414 continue;
1415 modname = linker_reloc_ptr(lf, mp->md_cval);
1416 nmodname = NULL;
1417 for (nmdp = start; nmdp < stop; nmdp++) {
1418 nmp = linker_reloc_ptr(lf, *nmdp);
1419 if (nmp->md_type != MDT_VERSION)
1420 continue;
1421 nmodname = linker_reloc_ptr(lf, nmp->md_cval);
1422 if (strcmp(modname, nmodname) == 0)
1423 break;
1424 }
1425 if (nmdp < stop) /* early exit, it's a self reference */
1426 continue;
1427 mod = modlist_lookup(modname, 0);
1428 if (mod) { /* woohoo, it's loaded already */
1429 lfdep = mod->container;
1430 lfdep->refs++;
1431 error = linker_file_add_dependancy(lf, lfdep);
1432 if (error)
1433 break;
1434 continue;
1435 }
1436 error = linker_load_module(modname, lf);
1437 if (error) {
1438 printf("KLD %s: depends on %s - not available\n",
1439 lf->filename, modname);
1440 break;
1441 }
1442 }
1443
1444 if (error)
1445 return error;
1446 linker_addmodules(lf, start, stop, 0);
1447 return error;
1448}
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 81937 2001-08-20 01:12:28Z dd $
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
57/* Metadata from the static kernel */
58SET_DECLARE(modmetadata_set, struct mod_metadata);
59
60MALLOC_DEFINE(M_LINKER, "linker", "kernel linker");
61
62linker_file_t linker_kernel_file;
63
64static struct lock lock; /* lock for the file list */
65static linker_class_list_t classes;
66static linker_file_list_t linker_files;
67static int next_file_id = 1;
68
69/* XXX wrong name; we're looking at version provision tags here, not modules */
70typedef TAILQ_HEAD(, modlist) modlisthead_t;
71struct modlist {
72 TAILQ_ENTRY(modlist) link; /* chain together all modules */
73 linker_file_t container;
74 const char *name;
75 int version;
76};
77typedef struct modlist *modlist_t;
78static modlisthead_t found_modules;
79
80static char *
81linker_strdup(const char *str)
82{
83 char *result;
84
85 if ((result = malloc((strlen(str) + 1), M_LINKER, M_WAITOK)) != NULL)
86 strcpy(result, str);
87 return(result);
88}
89
90static void
91linker_init(void* arg)
92{
93 lockinit(&lock, PVM, "klink", 0, 0);
94 TAILQ_INIT(&classes);
95 TAILQ_INIT(&linker_files);
96}
97
98SYSINIT(linker, SI_SUB_KLD, SI_ORDER_FIRST, linker_init, 0);
99
100int
101linker_add_class(linker_class_t lc)
102{
103 kobj_class_compile((kobj_class_t) lc);
104 TAILQ_INSERT_TAIL(&classes, lc, link);
105 return 0;
106}
107
108static void
109linker_file_sysinit(linker_file_t lf)
110{
111 struct sysinit** start, ** stop;
112 struct sysinit** sipp;
113 struct sysinit** xipp;
114 struct sysinit* save;
115
116 KLD_DPF(FILE, ("linker_file_sysinit: calling SYSINITs for %s\n",
117 lf->filename));
118
119 if (linker_file_lookup_set(lf, "sysinit_set", &start, &stop, NULL) != 0)
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 = start; sipp < stop; sipp++) {
129 for (xipp = sipp + 1; xipp < stop; 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 = start; sipp < stop; 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 sysinit** start, ** stop;
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 if (linker_file_lookup_set(lf, "sysuninit_set", &start, &stop, NULL) != 0)
166 return;
167
168 /*
169 * Perform a reverse bubble sort of the system initialization objects
170 * by their subsystem (primary key) and order (secondary key).
171 *
172 * Since some things care about execution order, this is the
173 * operation which ensures continued function.
174 */
175 for (sipp = start; sipp < stop; sipp++) {
176 for (xipp = sipp + 1; xipp < stop; xipp++) {
177 if ((*sipp)->subsystem > (*xipp)->subsystem ||
178 ((*sipp)->subsystem == (*xipp)->subsystem &&
179 (*sipp)->order >= (*xipp)->order))
180 continue; /* skip*/
181 save = *sipp;
182 *sipp = *xipp;
183 *xipp = save;
184 }
185 }
186
187 /*
188 * Traverse the (now) ordered list of system initialization tasks.
189 * Perform each task, and continue on to the next task.
190 */
191 for (sipp = start; sipp < stop; sipp++) {
192 if ((*sipp)->subsystem == SI_SUB_DUMMY)
193 continue; /* skip dummy task(s)*/
194
195 /* Call function */
196 (*((*sipp)->func))((*sipp)->udata);
197 }
198}
199
200static void
201linker_file_register_sysctls(linker_file_t lf)
202{
203 struct sysctl_oid **start, **stop, **oidp;
204
205 KLD_DPF(FILE, ("linker_file_register_sysctls: registering SYSCTLs for %s\n",
206 lf->filename));
207
208 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0)
209 return;
210
211 for (oidp = start; oidp < stop; oidp++)
212 sysctl_register_oid(*oidp);
213}
214
215static void
216linker_file_unregister_sysctls(linker_file_t lf)
217{
218 struct sysctl_oid **start, **stop, **oidp;
219
220 KLD_DPF(FILE, ("linker_file_unregister_sysctls: registering SYSCTLs for %s\n",
221 lf->filename));
222
223 if (linker_file_lookup_set(lf, "sysctl_set", &start, &stop, NULL) != 0)
224 return;
225
226 for (oidp = start; oidp < stop; oidp++)
227 sysctl_unregister_oid(*oidp);
228}
229
230static int
231linker_file_register_modules(linker_file_t lf)
232{
233 int error;
234 struct mod_metadata **start, **stop;
235 struct mod_metadata **mdp;
236 const moduledata_t *moddata;
237
238 KLD_DPF(FILE, ("linker_file_register_modules: registering modules in %s\n",
239 lf->filename));
240
241 if (linker_file_lookup_set(lf, "modmetadata_set", &start, &stop, 0) != 0) {
242 /*
243 * This fallback should be unnecessary, but if we get booted from
244 * boot2 instead of loader and we are missing our metadata then
245 * we have to try the best we can.
246 */
247 if (lf == linker_kernel_file) {
248 start = SET_BEGIN(modmetadata_set);
249 stop = SET_LIMIT(modmetadata_set);
250 } else {
251 return 0;
252 }
253 }
254 for (mdp = start; mdp < stop; mdp++) {
255 if ((*mdp)->md_type != MDT_MODULE)
256 continue;
257 moddata = (*mdp)->md_data;
258 KLD_DPF(FILE, ("Registering module %s in %s\n",
259 moddata->name, lf->filename));
260 if (module_lookupbyname(moddata->name) != NULL) {
261 printf("Warning: module %s already exists\n", moddata->name);
262 continue; /* or return a error ? */
263 }
264 error = module_register(moddata, lf);
265 if (error)
266 printf("Module %s failed to register: %d\n", moddata->name, error);
267 }
268 return 0;
269}
270
271static void
272linker_init_kernel_modules(void)
273{
274 linker_file_register_modules(linker_kernel_file);
275}
276
277SYSINIT(linker_kernel, SI_SUB_KLD, SI_ORDER_ANY, linker_init_kernel_modules, 0);
278
279int
280linker_load_file(const char* filename, linker_file_t* result)
281{
282 linker_class_t lc;
283 linker_file_t lf;
284 int foundfile, error = 0;
285
286 /* Refuse to load modules if securelevel raised */
287 if (securelevel > 0)
288 return EPERM;
289
290 lf = linker_find_file_by_name(filename);
291 if (lf) {
292 KLD_DPF(FILE, ("linker_load_file: file %s is already loaded, incrementing refs\n", filename));
293 *result = lf;
294 lf->refs++;
295 goto out;
296 }
297
298 lf = NULL;
299 foundfile = 0;
300 TAILQ_FOREACH(lc, &classes, link) {
301 KLD_DPF(FILE, ("linker_load_file: trying to load %s\n",
302 filename));
303 error = LINKER_LOAD_FILE(lc, filename, &lf);
304 /*
305 * If we got something other than ENOENT, then it exists but we cannot
306 * load it for some other reason.
307 */
308 if (error != ENOENT)
309 foundfile = 1;
310 if (lf) {
311 linker_file_register_modules(lf);
312 linker_file_register_sysctls(lf);
313 linker_file_sysinit(lf);
314 lf->flags |= LINKER_FILE_LINKED;
315
316 *result = lf;
317 error = 0;
318 goto out;
319 }
320 }
321 /*
322 * Less than ideal, but tells the user whether it failed to load or
323 * the module was not found.
324 */
325 if (foundfile)
326 error = ENOEXEC; /* Format not recognised (or unloadable) */
327 else
328 error = ENOENT; /* Nothing found */
329
330out:
331 return error;
332}
333
334int
335linker_reference_module(const char *modname, linker_file_t *result)
336{
337 char *pathname;
338 int res;
339
340 /*
341 * There will be a system to look up or guess a file name from
342 * a module name.
343 * For now we just try to load a file with the same name.
344 */
345 if ((pathname = linker_search_path(modname)) == NULL)
346 return (ENOENT);
347
348 /*
349 * If the module is already loaded or built into the kernel,
350 * linker_load_file() simply bumps it's refcount.
351 */
352 res = linker_load_file(pathname, result);
353
354 free(pathname, M_LINKER);
355
356 return (res);
357}
358
359linker_file_t
360linker_find_file_by_name(const char* filename)
361{
362 linker_file_t lf = 0;
363 char *koname;
364
365 koname = malloc(strlen(filename) + 4, M_LINKER, M_WAITOK);
366 if (koname == NULL)
367 goto out;
368 sprintf(koname, "%s.ko", filename);
369
370 lockmgr(&lock, LK_SHARED, 0, curproc);
371 TAILQ_FOREACH(lf, &linker_files, link) {
372 if (!strcmp(lf->filename, koname))
373 break;
374 if (!strcmp(lf->filename, filename))
375 break;
376 }
377 lockmgr(&lock, LK_RELEASE, 0, curproc);
378
379out:
380 if (koname)
381 free(koname, M_LINKER);
382 return lf;
383}
384
385linker_file_t
386linker_find_file_by_id(int fileid)
387{
388 linker_file_t lf = 0;
389
390 lockmgr(&lock, LK_SHARED, 0, curproc);
391 TAILQ_FOREACH(lf, &linker_files, link)
392 if (lf->id == fileid)
393 break;
394 lockmgr(&lock, LK_RELEASE, 0, curproc);
395
396 return lf;
397}
398
399linker_file_t
400linker_make_file(const char* pathname, linker_class_t lc)
401{
402 linker_file_t lf = 0;
403 const char *filename;
404
405 filename = linker_basename(pathname);
406
407 KLD_DPF(FILE, ("linker_make_file: new file, filename=%s\n", filename));
408 lockmgr(&lock, LK_EXCLUSIVE, 0, curproc);
409 lf = (linker_file_t) kobj_create((kobj_class_t) lc, M_LINKER, M_WAITOK);
410 if (!lf)
411 goto out;
412
413 lf->refs = 1;
414 lf->userrefs = 0;
415 lf->flags = 0;
416 lf->filename = linker_strdup(filename);
417 lf->id = next_file_id++;
418 lf->ndeps = 0;
419 lf->deps = NULL;
420 STAILQ_INIT(&lf->common);
421 TAILQ_INIT(&lf->modules);
422
423 TAILQ_INSERT_TAIL(&linker_files, lf, link);
424
425out:
426 lockmgr(&lock, LK_RELEASE, 0, curproc);
427 return lf;
428}
429
430int
431linker_file_unload(linker_file_t file)
432{
433 module_t mod, next;
434 modlist_t ml, nextml;
435 struct common_symbol* cp;
436 int error = 0;
437 int i;
438
439 /* Refuse to unload modules if securelevel raised */
440 if (securelevel > 0)
441 return EPERM;
442
443 KLD_DPF(FILE, ("linker_file_unload: lf->refs=%d\n", file->refs));
444 lockmgr(&lock, LK_EXCLUSIVE, 0, curproc);
445 if (file->refs == 1) {
446 KLD_DPF(FILE, ("linker_file_unload: file is unloading, informing modules\n"));
447 /*
448 * Inform any modules associated with this file.
449 */
450 for (mod = TAILQ_FIRST(&file->modules); mod; mod = next) {
451 next = module_getfnext(mod);
452
453 /*
454 * Give the module a chance to veto the unload.
455 */
456 if ((error = module_unload(mod)) != 0) {
457 KLD_DPF(FILE, ("linker_file_unload: module %x vetoes unload\n",
458 mod));
459 lockmgr(&lock, LK_RELEASE, 0, curproc);
460 goto out;
461 }
462
463 module_release(mod);
464 }
465 }
466
467 file->refs--;
468 if (file->refs > 0) {
469 lockmgr(&lock, LK_RELEASE, 0, curproc);
470 goto out;
471 }
472
473 for (ml = TAILQ_FIRST(&found_modules); ml; ml = nextml) {
474 nextml = TAILQ_NEXT(ml, link);
475 if (ml->container == file) {
476 TAILQ_REMOVE(&found_modules, ml, link);
477 }
478 }
479
480 /* Don't try to run SYSUNINITs if we are unloaded due to a link error */
481 if (file->flags & LINKER_FILE_LINKED) {
482 linker_file_sysuninit(file);
483 linker_file_unregister_sysctls(file);
484 }
485
486 TAILQ_REMOVE(&linker_files, file, link);
487 lockmgr(&lock, LK_RELEASE, 0, curproc);
488
489 if (file->deps) {
490 for (i = 0; i < file->ndeps; i++)
491 linker_file_unload(file->deps[i]);
492 free(file->deps, M_LINKER);
493 file->deps = NULL;
494 }
495
496 for (cp = STAILQ_FIRST(&file->common); cp;
497 cp = STAILQ_FIRST(&file->common)) {
498 STAILQ_REMOVE(&file->common, cp, common_symbol, link);
499 free(cp, M_LINKER);
500 }
501
502 LINKER_UNLOAD(file);
503 if (file->filename) {
504 free(file->filename, M_LINKER);
505 file->filename = NULL;
506 }
507 kobj_delete((kobj_t) file, M_LINKER);
508
509out:
510 return error;
511}
512
513int
514linker_file_add_dependancy(linker_file_t file, linker_file_t dep)
515{
516 linker_file_t* newdeps;
517
518 newdeps = malloc((file->ndeps + 1) * sizeof(linker_file_t*),
519 M_LINKER, M_WAITOK | M_ZERO);
520 if (newdeps == NULL)
521 return ENOMEM;
522
523 if (file->deps) {
524 bcopy(file->deps, newdeps, file->ndeps * sizeof(linker_file_t*));
525 free(file->deps, M_LINKER);
526 }
527 file->deps = newdeps;
528 file->deps[file->ndeps] = dep;
529 file->ndeps++;
530
531 return 0;
532}
533
534/*
535 * Locate a linker set and its contents.
536 * This is a helper function to avoid linker_if.h exposure elsewhere.
537 * Note: firstp and lastp are really void ***
538 */
539int
540linker_file_lookup_set(linker_file_t file, const char *name,
541 void *firstp, void *lastp, int *countp)
542{
543
544 return LINKER_LOOKUP_SET(file, name, firstp, lastp, countp);
545}
546
547caddr_t
548linker_file_lookup_symbol(linker_file_t file, const char* name, int deps)
549{
550 c_linker_sym_t sym;
551 linker_symval_t symval;
552 caddr_t address;
553 size_t common_size = 0;
554 int i;
555
556 KLD_DPF(SYM, ("linker_file_lookup_symbol: file=%x, name=%s, deps=%d\n",
557 file, name, deps));
558
559 if (LINKER_LOOKUP_SYMBOL(file, name, &sym) == 0) {
560 LINKER_SYMBOL_VALUES(file, sym, &symval);
561 if (symval.value == 0)
562 /*
563 * For commons, first look them up in the dependancies and
564 * only allocate space if not found there.
565 */
566 common_size = symval.size;
567 else {
568 KLD_DPF(SYM, ("linker_file_lookup_symbol: symbol.value=%x\n", symval.value));
569 return symval.value;
570 }
571 }
572
573 if (deps) {
574 for (i = 0; i < file->ndeps; i++) {
575 address = linker_file_lookup_symbol(file->deps[i], name, 0);
576 if (address) {
577 KLD_DPF(SYM, ("linker_file_lookup_symbol: deps value=%x\n", address));
578 return address;
579 }
580 }
581 }
582
583 if (common_size > 0) {
584 /*
585 * This is a common symbol which was not found in the
586 * dependancies. We maintain a simple common symbol table in
587 * the file object.
588 */
589 struct common_symbol* cp;
590
591 STAILQ_FOREACH(cp, &file->common, link)
592 if (!strcmp(cp->name, name)) {
593 KLD_DPF(SYM, ("linker_file_lookup_symbol: old common value=%x\n", cp->address));
594 return cp->address;
595 }
596
597 /*
598 * Round the symbol size up to align.
599 */
600 common_size = (common_size + sizeof(int) - 1) & -sizeof(int);
601 cp = malloc(sizeof(struct common_symbol)
602 + common_size
603 + strlen(name) + 1,
604 M_LINKER, M_WAITOK | M_ZERO);
605 if (!cp) {
606 KLD_DPF(SYM, ("linker_file_lookup_symbol: nomem\n"));
607 return 0;
608 }
609
610 cp->address = (caddr_t) (cp + 1);
611 cp->name = cp->address + common_size;
612 strcpy(cp->name, name);
613 bzero(cp->address, common_size);
614 STAILQ_INSERT_TAIL(&file->common, cp, link);
615
616 KLD_DPF(SYM, ("linker_file_lookup_symbol: new common value=%x\n", cp->address));
617 return cp->address;
618 }
619
620 KLD_DPF(SYM, ("linker_file_lookup_symbol: fail\n"));
621 return 0;
622}
623
624#ifdef DDB
625/*
626 * DDB Helpers. DDB has to look across multiple files with their own
627 * symbol tables and string tables.
628 *
629 * Note that we do not obey list locking protocols here. We really don't
630 * need DDB to hang because somebody's got the lock held. We'll take the
631 * chance that the files list is inconsistant instead.
632 */
633
634int
635linker_ddb_lookup(const char *symstr, c_linker_sym_t *sym)
636{
637 linker_file_t lf;
638
639 TAILQ_FOREACH(lf, &linker_files, link) {
640 if (LINKER_LOOKUP_SYMBOL(lf, symstr, sym) == 0)
641 return 0;
642 }
643 return ENOENT;
644}
645
646int
647linker_ddb_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp)
648{
649 linker_file_t lf;
650 u_long off = (uintptr_t)value;
651 u_long diff, bestdiff;
652 c_linker_sym_t best;
653 c_linker_sym_t es;
654
655 best = 0;
656 bestdiff = off;
657 TAILQ_FOREACH(lf, &linker_files, link) {
658 if (LINKER_SEARCH_SYMBOL(lf, value, &es, &diff) != 0)
659 continue;
660 if (es != 0 && diff < bestdiff) {
661 best = es;
662 bestdiff = diff;
663 }
664 if (bestdiff == 0)
665 break;
666 }
667 if (best) {
668 *sym = best;
669 *diffp = bestdiff;
670 return 0;
671 } else {
672 *sym = 0;
673 *diffp = off;
674 return ENOENT;
675 }
676}
677
678int
679linker_ddb_symbol_values(c_linker_sym_t sym, linker_symval_t *symval)
680{
681 linker_file_t lf;
682
683 TAILQ_FOREACH(lf, &linker_files, link) {
684 if (LINKER_SYMBOL_VALUES(lf, sym, symval) == 0)
685 return 0;
686 }
687 return ENOENT;
688}
689
690#endif
691
692/*
693 * Syscalls.
694 */
695
696int
697kldload(struct proc* p, struct kldload_args* uap)
698{
699 char* pathname, *realpath;
700 const char *filename;
701 linker_file_t lf;
702 int error = 0;
703
704 p->p_retval[0] = -1;
705
706 if (securelevel > 0) /* redundant, but that's OK */
707 return EPERM;
708
709 if ((error = suser(p)) != 0)
710 return error;
711
712 realpath = NULL;
713 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
714 if ((error = copyinstr(SCARG(uap, file), pathname, MAXPATHLEN, NULL)) != 0)
715 goto out;
716
717 realpath = linker_search_path(pathname);
718 if (realpath == NULL) {
719 error = ENOENT;
720 goto out;
721 }
722 /* Can't load more than one file with the same name */
723 filename = linker_basename(realpath);
724 if (linker_find_file_by_name(filename)) {
725 error = EEXIST;
726 goto out;
727 }
728
729 if ((error = linker_load_file(realpath, &lf)) != 0)
730 goto out;
731
732 lf->userrefs++;
733 p->p_retval[0] = lf->id;
734
735out:
736 if (pathname)
737 free(pathname, M_TEMP);
738 if (realpath)
739 free(realpath, M_LINKER);
740 return error;
741}
742
743int
744kldunload(struct proc* p, struct kldunload_args* uap)
745{
746 linker_file_t lf;
747 int error = 0;
748
749 if (securelevel > 0) /* redundant, but that's OK */
750 return EPERM;
751
752 if ((error = suser(p)) != 0)
753 return error;
754
755 lf = linker_find_file_by_id(SCARG(uap, fileid));
756 if (lf) {
757 KLD_DPF(FILE, ("kldunload: lf->userrefs=%d\n", lf->userrefs));
758 if (lf->userrefs == 0) {
759 printf("kldunload: attempt to unload file that was loaded by the kernel\n");
760 error = EBUSY;
761 goto out;
762 }
763 lf->userrefs--;
764 error = linker_file_unload(lf);
765 if (error)
766 lf->userrefs++;
767 } else
768 error = ENOENT;
769
770out:
771 return error;
772}
773
774int
775kldfind(struct proc* p, struct kldfind_args* uap)
776{
777 char* pathname;
778 const char *filename;
779 linker_file_t lf;
780 int error = 0;
781
782 p->p_retval[0] = -1;
783
784 pathname = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
785 if ((error = copyinstr(SCARG(uap, file), pathname, MAXPATHLEN, NULL)) != 0)
786 goto out;
787
788 filename = linker_basename(pathname);
789
790 lf = linker_find_file_by_name(filename);
791 if (lf)
792 p->p_retval[0] = lf->id;
793 else
794 error = ENOENT;
795
796out:
797 if (pathname)
798 free(pathname, M_TEMP);
799 return error;
800}
801
802int
803kldnext(struct proc* p, struct kldnext_args* uap)
804{
805 linker_file_t lf;
806 int error = 0;
807
808 if (SCARG(uap, fileid) == 0) {
809 if (TAILQ_FIRST(&linker_files))
810 p->p_retval[0] = TAILQ_FIRST(&linker_files)->id;
811 else
812 p->p_retval[0] = 0;
813 return 0;
814 }
815
816 lf = linker_find_file_by_id(SCARG(uap, fileid));
817 if (lf) {
818 if (TAILQ_NEXT(lf, link))
819 p->p_retval[0] = TAILQ_NEXT(lf, link)->id;
820 else
821 p->p_retval[0] = 0;
822 } else
823 error = ENOENT;
824
825 return error;
826}
827
828int
829kldstat(struct proc* p, struct kldstat_args* uap)
830{
831 linker_file_t lf;
832 int error = 0;
833 int version;
834 struct kld_file_stat* stat;
835 int namelen;
836
837 lf = linker_find_file_by_id(SCARG(uap, fileid));
838 if (!lf) {
839 error = ENOENT;
840 goto out;
841 }
842
843 stat = SCARG(uap, stat);
844
845 /*
846 * Check the version of the user's structure.
847 */
848 if ((error = copyin(&stat->version, &version, sizeof(version))) != 0)
849 goto out;
850 if (version != sizeof(struct kld_file_stat)) {
851 error = EINVAL;
852 goto out;
853 }
854
855 namelen = strlen(lf->filename) + 1;
856 if (namelen > MAXPATHLEN)
857 namelen = MAXPATHLEN;
858 if ((error = copyout(lf->filename, &stat->name[0], namelen)) != 0)
859 goto out;
860 if ((error = copyout(&lf->refs, &stat->refs, sizeof(int))) != 0)
861 goto out;
862 if ((error = copyout(&lf->id, &stat->id, sizeof(int))) != 0)
863 goto out;
864 if ((error = copyout(&lf->address, &stat->address, sizeof(caddr_t))) != 0)
865 goto out;
866 if ((error = copyout(&lf->size, &stat->size, sizeof(size_t))) != 0)
867 goto out;
868
869 p->p_retval[0] = 0;
870
871out:
872 return error;
873}
874
875int
876kldfirstmod(struct proc* p, struct kldfirstmod_args* uap)
877{
878 linker_file_t lf;
879 int error = 0;
880
881 lf = linker_find_file_by_id(SCARG(uap, fileid));
882 if (lf) {
883 if (TAILQ_FIRST(&lf->modules))
884 p->p_retval[0] = module_getid(TAILQ_FIRST(&lf->modules));
885 else
886 p->p_retval[0] = 0;
887 } else
888 error = ENOENT;
889
890 return error;
891}
892
893int
894kldsym(struct proc *p, struct kldsym_args *uap)
895{
896 char *symstr = NULL;
897 c_linker_sym_t sym;
898 linker_symval_t symval;
899 linker_file_t lf;
900 struct kld_sym_lookup lookup;
901 int error = 0;
902
903 if ((error = copyin(SCARG(uap, data), &lookup, sizeof(lookup))) != 0)
904 goto out;
905 if (lookup.version != sizeof(lookup) || SCARG(uap, cmd) != KLDSYM_LOOKUP) {
906 error = EINVAL;
907 goto out;
908 }
909
910 symstr = malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
911 if ((error = copyinstr(lookup.symname, symstr, MAXPATHLEN, NULL)) != 0)
912 goto out;
913
914 if (SCARG(uap, fileid) != 0) {
915 lf = linker_find_file_by_id(SCARG(uap, fileid));
916 if (lf == NULL) {
917 error = ENOENT;
918 goto out;
919 }
920 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 &&
921 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) {
922 lookup.symvalue = (uintptr_t)symval.value;
923 lookup.symsize = symval.size;
924 error = copyout(&lookup, SCARG(uap, data), sizeof(lookup));
925 } else
926 error = ENOENT;
927 } else {
928 TAILQ_FOREACH(lf, &linker_files, link) {
929 if (LINKER_LOOKUP_SYMBOL(lf, symstr, &sym) == 0 &&
930 LINKER_SYMBOL_VALUES(lf, sym, &symval) == 0) {
931 lookup.symvalue = (uintptr_t)symval.value;
932 lookup.symsize = symval.size;
933 error = copyout(&lookup, SCARG(uap, data), sizeof(lookup));
934 break;
935 }
936 }
937 if (!lf)
938 error = ENOENT;
939 }
940out:
941 if (symstr)
942 free(symstr, M_TEMP);
943 return error;
944}
945
946/*
947 * Preloaded module support
948 */
949
950static modlist_t
951modlist_lookup(const char *name, int ver)
952{
953 modlist_t mod;
954
955 TAILQ_FOREACH(mod, &found_modules, link) {
956 if (strcmp(mod->name, name) == 0 && (ver == 0 || mod->version == ver))
957 return mod;
958 }
959 return NULL;
960}
961
962static modlist_t
963modlist_newmodule(const char *modname, int version, linker_file_t container)
964{
965 modlist_t mod;
966
967 mod = malloc(sizeof(struct modlist), M_LINKER, M_NOWAIT);
968 if (mod == NULL)
969 panic("no memory for module list");
970 bzero(mod, sizeof(*mod));
971 mod->container = container;
972 mod->name = modname;
973 mod->version = version;
974 TAILQ_INSERT_TAIL(&found_modules, mod, link);
975 return mod;
976}
977
978/*
979 * This routine is cheap and nasty but will work for data pointers.
980 */
981static void *
982linker_reloc_ptr(linker_file_t lf, const void *offset)
983{
984 return lf->address + (uintptr_t)offset;
985}
986
987/*
988 * Dereference MDT_VERSION metadata into module name and version
989 */
990static void
991linker_mdt_version(linker_file_t lf, struct mod_metadata *mp,
992 const char **modname, int *version)
993{
994 struct mod_version *mvp;
995
996 if (modname)
997 *modname = linker_reloc_ptr(lf, mp->md_cval);
998 if (version) {
999 mvp = linker_reloc_ptr(lf, mp->md_data);
1000 *version = mvp->mv_version;
1001 }
1002}
1003
1004/*
1005 * Dereference MDT_DEPEND metadata into module name and mod_depend structure
1006 */
1007static void
1008linker_mdt_depend(linker_file_t lf, struct mod_metadata *mp,
1009 const char **modname, struct mod_depend **verinfo)
1010{
1011
1012 if (modname)
1013 *modname = linker_reloc_ptr(lf, mp->md_cval);
1014 if (verinfo)
1015 *verinfo = linker_reloc_ptr(lf, mp->md_data);
1016}
1017
1018static void
1019linker_addmodules(linker_file_t lf, struct mod_metadata **start,
1020 struct mod_metadata **stop, int preload)
1021{
1022 struct mod_metadata *mp, **mdp;
1023 const char *modname;
1024 int ver;
1025
1026 for (mdp = start; mdp < stop; mdp++) {
1027 if (preload)
1028 mp = *mdp;
1029 else
1030 mp = linker_reloc_ptr(lf, *mdp);
1031 if (mp->md_type != MDT_VERSION)
1032 continue;
1033 if (preload) {
1034 modname = mp->md_cval;
1035 ver = ((struct mod_version*)mp->md_data)->mv_version;
1036 } else
1037 linker_mdt_version(lf, mp, &modname, &ver);
1038 if (modlist_lookup(modname, ver) != NULL) {
1039 printf("module %s already present!\n", modname);
1040 /* XXX what can we do? this is a build error. :-( */
1041 continue;
1042 }
1043 modlist_newmodule(modname, ver, lf);
1044 }
1045}
1046
1047static void
1048linker_preload(void* arg)
1049{
1050 caddr_t modptr;
1051 const char *modname, *nmodname;
1052 char *modtype;
1053 linker_file_t lf;
1054 linker_class_t lc;
1055 int error;
1056 linker_file_list_t loaded_files;
1057 linker_file_list_t depended_files;
1058 struct mod_metadata *mp, *nmp;
1059 struct mod_metadata **start, **stop, **mdp, **nmdp;
1060 struct mod_depend *verinfo;
1061 int nver;
1062 int resolves;
1063 modlist_t mod;
1064 struct sysinit **si_start, **si_stop;
1065
1066 TAILQ_INIT(&loaded_files);
1067 TAILQ_INIT(&depended_files);
1068 TAILQ_INIT(&found_modules);
1069 error = 0;
1070
1071 modptr = NULL;
1072 while ((modptr = preload_search_next_name(modptr)) != NULL) {
1073 modname = (char *)preload_search_info(modptr, MODINFO_NAME);
1074 modtype = (char *)preload_search_info(modptr, MODINFO_TYPE);
1075 if (modname == NULL) {
1076 printf("Preloaded module at %p does not have a name!\n", modptr);
1077 continue;
1078 }
1079 if (modtype == NULL) {
1080 printf("Preloaded module at %p does not have a type!\n", modptr);
1081 continue;
1082 }
1083 printf("Preloaded %s \"%s\" at %p.\n", modtype, modname, modptr);
1084 lf = NULL;
1085 TAILQ_FOREACH(lc, &classes, link) {
1086 error = LINKER_LINK_PRELOAD(lc, modname, &lf);
1087 if (error) {
1088 lf = NULL;
1089 break;
1090 }
1091 }
1092 if (lf)
1093 TAILQ_INSERT_TAIL(&loaded_files, lf, loaded);
1094 }
1095
1096 /*
1097 * First get a list of stuff in the kernel.
1098 */
1099 if (linker_file_lookup_set(linker_kernel_file, MDT_SETNAME, &start, &stop,
1100 NULL) == 0)
1101 linker_addmodules(linker_kernel_file, start, stop, 1);
1102
1103 /*
1104 * this is a once-off kinky bubble sort
1105 * resolve relocation dependency requirements
1106 */
1107restart:
1108 TAILQ_FOREACH(lf, &loaded_files, loaded) {
1109 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop, NULL);
1110 /*
1111 * First, look to see if we would successfully link with this stuff.
1112 */
1113 resolves = 1; /* unless we know otherwise */
1114 if (!error) {
1115 for (mdp = start; mdp < stop; mdp++) {
1116 mp = linker_reloc_ptr(lf, *mdp);
1117 if (mp->md_type != MDT_DEPEND)
1118 continue;
1119 linker_mdt_depend(lf, mp, &modname, &verinfo);
1120 for (nmdp = start; nmdp < stop; nmdp++) {
1121 nmp = linker_reloc_ptr(lf, *nmdp);
1122 if (nmp->md_type != MDT_VERSION)
1123 continue;
1124 linker_mdt_version(lf, nmp, &nmodname, NULL);
1125 nmodname = linker_reloc_ptr(lf, nmp->md_cval);
1126 if (strcmp(modname, nmodname) == 0)
1127 break;
1128 }
1129 if (nmdp < stop) /* it's a self reference */
1130 continue;
1131 if (modlist_lookup(modname, 0) == NULL) {
1132 /* ok, the module isn't here yet, we are not finished */
1133 resolves = 0;
1134 }
1135 }
1136 }
1137 /*
1138 * OK, if we found our modules, we can link. So, "provide" the
1139 * modules inside and add it to the end of the link order list.
1140 */
1141 if (resolves) {
1142 if (!error) {
1143 for (mdp = start; mdp < stop; mdp++) {
1144 mp = linker_reloc_ptr(lf, *mdp);
1145 if (mp->md_type != MDT_VERSION)
1146 continue;
1147 linker_mdt_version(lf, mp, &modname, &nver);
1148 if (modlist_lookup(modname, nver) != NULL) {
1149 printf("module %s already present!\n", modname);
1150 linker_file_unload(lf);
1151 TAILQ_REMOVE(&loaded_files, lf, loaded);
1152 goto restart; /* we changed the tailq next ptr */
1153 }
1154 modlist_newmodule(modname, nver, lf);
1155 }
1156 }
1157 TAILQ_REMOVE(&loaded_files, lf, loaded);
1158 TAILQ_INSERT_TAIL(&depended_files, lf, loaded);
1159 /*
1160 * Since we provided modules, we need to restart the sort so
1161 * that the previous files that depend on us have a chance.
1162 * Also, we've busted the tailq next pointer with the REMOVE.
1163 */
1164 goto restart;
1165 }
1166 }
1167
1168 /*
1169 * At this point, we check to see what could not be resolved..
1170 */
1171 TAILQ_FOREACH(lf, &loaded_files, loaded) {
1172 printf("KLD file %s is missing dependencies\n", lf->filename);
1173 linker_file_unload(lf);
1174 TAILQ_REMOVE(&loaded_files, lf, loaded);
1175 }
1176
1177 /*
1178 * We made it. Finish off the linking in the order we determined.
1179 */
1180 TAILQ_FOREACH(lf, &depended_files, loaded) {
1181 if (linker_kernel_file) {
1182 linker_kernel_file->refs++;
1183 error = linker_file_add_dependancy(lf, linker_kernel_file);
1184 if (error)
1185 panic("cannot add dependency");
1186 }
1187 lf->userrefs++; /* so we can (try to) kldunload it */
1188 error = linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop, NULL);
1189 if (!error) {
1190 for (mdp = start; mdp < stop; mdp++) {
1191 mp = linker_reloc_ptr(lf, *mdp);
1192 if (mp->md_type != MDT_DEPEND)
1193 continue;
1194 linker_mdt_depend(lf, mp, &modname, &verinfo);
1195 mod = modlist_lookup(modname, 0);
1196 mod->container->refs++;
1197 error = linker_file_add_dependancy(lf, mod->container);
1198 if (error)
1199 panic("cannot add dependency");
1200 }
1201 }
1202
1203 /*
1204 * Now do relocation etc using the symbol search paths established by
1205 * the dependencies
1206 */
1207 error = LINKER_LINK_PRELOAD_FINISH(lf);
1208 if (error) {
1209 printf("KLD file %s - could not finalize loading\n", lf->filename);
1210 linker_file_unload(lf);
1211 continue;
1212 }
1213
1214 linker_file_register_modules(lf);
1215 if (linker_file_lookup_set(lf, "sysinit_set", &si_start, &si_stop, NULL) == 0)
1216 sysinit_add(si_start, si_stop);
1217 linker_file_register_sysctls(lf);
1218 lf->flags |= LINKER_FILE_LINKED;
1219 }
1220 /* woohoo! we made it! */
1221}
1222
1223SYSINIT(preload, SI_SUB_KLD, SI_ORDER_MIDDLE, linker_preload, 0);
1224
1225/*
1226 * Search for a not-loaded module by name.
1227 *
1228 * Modules may be found in the following locations:
1229 *
1230 * - preloaded (result is just the module name)
1231 * - on disk (result is full path to module)
1232 *
1233 * If the module name is qualified in any way (contains path, etc.)
1234 * the we simply return a copy of it.
1235 *
1236 * The search path can be manipulated via sysctl. Note that we use the ';'
1237 * character as a separator to be consistent with the bootloader.
1238 */
1239
1240static char linker_path[MAXPATHLEN] = "/boot/kernel;/boot/modules/;/modules/";
1241
1242SYSCTL_STRING(_kern, OID_AUTO, module_path, CTLFLAG_RW, linker_path,
1243 sizeof(linker_path), "module load search path");
1244
1245TUNABLE_STR("module_path", linker_path, sizeof(linker_path));
1246
1247static char *linker_ext_list[] = {
1248 ".ko",
1249 "",
1250 NULL
1251};
1252
1253static char *
1254linker_search_path(const char *name)
1255{
1256 struct nameidata nd;
1257 struct proc *p = curproc; /* XXX */
1258 char *cp, *ep, *result, **cpp;
1259 int error, extlen, len, flags;
1260 enum vtype type;
1261
1262 /* qualified at all? */
1263 if (index(name, '/'))
1264 return(linker_strdup(name));
1265
1266 extlen = 0;
1267 for (cpp = linker_ext_list; *cpp; cpp++) {
1268 len = strlen(*cpp);
1269 if (len > extlen)
1270 extlen = len;
1271 }
1272 extlen++; /* trailing '\0' */
1273
1274 /* traverse the linker path */
1275 cp = linker_path;
1276 len = strlen(name);
1277 for (;;) {
1278
1279 /* find the end of this component */
1280 for (ep = cp; (*ep != 0) && (*ep != ';'); ep++)
1281 ;
1282 result = malloc((len + (ep - cp) + extlen + 1), M_LINKER, M_WAITOK);
1283 if (result == NULL) /* actually ENOMEM */
1284 return(NULL);
1285 for (cpp = linker_ext_list; *cpp; cpp++) {
1286 strncpy(result, cp, ep - cp);
1287 strcpy(result + (ep - cp), "/");
1288 strcat(result, name);
1289 strcat(result, *cpp);
1290 /*
1291 * Attempt to open the file, and return the path if we succeed
1292 * and it's a regular file.
1293 */
1294 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, result, p);
1295 flags = FREAD;
1296 error = vn_open(&nd, &flags, 0);
1297 if (error == 0) {
1298 NDFREE(&nd, NDF_ONLY_PNBUF);
1299 type = nd.ni_vp->v_type;
1300 VOP_UNLOCK(nd.ni_vp, 0, p);
1301 vn_close(nd.ni_vp, FREAD, p->p_ucred, p);
1302 if (type == VREG)
1303 return(result);
1304 }
1305 }
1306 free(result, M_LINKER);
1307
1308 if (*ep == 0)
1309 break;
1310 cp = ep + 1;
1311 }
1312 return(NULL);
1313}
1314
1315static const char *
1316linker_basename(const char* path)
1317{
1318 const char *filename;
1319
1320 filename = rindex(path, '/');
1321 if (filename == NULL)
1322 return path;
1323 if (filename[1])
1324 filename++;
1325 return filename;
1326}
1327
1328/*
1329 * Find a file which contains given module and load it,
1330 * if "parent" is not NULL, register a reference to it.
1331 */
1332static int
1333linker_load_module(const char *modname, struct linker_file *parent)
1334{
1335 linker_file_t lfdep;
1336 const char *filename;
1337 char *pathname;
1338 int error;
1339
1340 /*
1341 * There will be a system to look up or guess a file name from
1342 * a module name.
1343 * For now we just try to load a file with the same name.
1344 */
1345 pathname = linker_search_path(modname);
1346 if (pathname == NULL)
1347 return ENOENT;
1348
1349 /* Can't load more than one file with the same basename */
1350 filename = linker_basename(pathname);
1351 if (linker_find_file_by_name(filename)) {
1352 error = EEXIST;
1353 goto out;
1354 }
1355
1356 do {
1357 error = linker_load_file(pathname, &lfdep);
1358 if (error)
1359 break;
1360 if (parent) {
1361 error = linker_file_add_dependancy(parent, lfdep);
1362 if (error)
1363 break;
1364 }
1365 } while(0);
1366out:
1367 if (pathname)
1368 free(pathname, M_LINKER);
1369 return error;
1370}
1371
1372/*
1373 * This routine is responsible for finding dependencies of userland
1374 * initiated kldload(2)'s of files.
1375 */
1376int
1377linker_load_dependancies(linker_file_t lf)
1378{
1379 linker_file_t lfdep;
1380 struct mod_metadata **start, **stop, **mdp, **nmdp;
1381 struct mod_metadata *mp, *nmp;
1382 modlist_t mod;
1383 const char *modname, *nmodname;
1384 int ver, error = 0, count;
1385
1386 /*
1387 * All files are dependant on /kernel.
1388 */
1389 if (linker_kernel_file) {
1390 linker_kernel_file->refs++;
1391 error = linker_file_add_dependancy(lf, linker_kernel_file);
1392 if (error)
1393 return error;
1394 }
1395
1396 if (linker_file_lookup_set(lf, MDT_SETNAME, &start, &stop, &count) != 0)
1397 return 0;
1398 for (mdp = start; mdp < stop; mdp++) {
1399 mp = linker_reloc_ptr(lf, *mdp);
1400 if (mp->md_type != MDT_VERSION)
1401 continue;
1402 linker_mdt_version(lf, mp, &modname, &ver);
1403 mod = modlist_lookup(modname, ver);
1404 if (mod != NULL) {
1405 printf("interface %s.%d already present in the KLD '%s'!\n",
1406 modname, ver, mod->container->filename);
1407 return EEXIST;
1408 }
1409 }
1410
1411 for (mdp = start; mdp < stop; mdp++) {
1412 mp = linker_reloc_ptr(lf, *mdp);
1413 if (mp->md_type != MDT_DEPEND)
1414 continue;
1415 modname = linker_reloc_ptr(lf, mp->md_cval);
1416 nmodname = NULL;
1417 for (nmdp = start; nmdp < stop; nmdp++) {
1418 nmp = linker_reloc_ptr(lf, *nmdp);
1419 if (nmp->md_type != MDT_VERSION)
1420 continue;
1421 nmodname = linker_reloc_ptr(lf, nmp->md_cval);
1422 if (strcmp(modname, nmodname) == 0)
1423 break;
1424 }
1425 if (nmdp < stop) /* early exit, it's a self reference */
1426 continue;
1427 mod = modlist_lookup(modname, 0);
1428 if (mod) { /* woohoo, it's loaded already */
1429 lfdep = mod->container;
1430 lfdep->refs++;
1431 error = linker_file_add_dependancy(lf, lfdep);
1432 if (error)
1433 break;
1434 continue;
1435 }
1436 error = linker_load_module(modname, lf);
1437 if (error) {
1438 printf("KLD %s: depends on %s - not available\n",
1439 lf->filename, modname);
1440 break;
1441 }
1442 }
1443
1444 if (error)
1445 return error;
1446 linker_addmodules(lf, start, stop, 0);
1447 return error;
1448}