623a1697a452315c94795c70d199984ee81c04cf
[project/ubox.git] / kmodloader.c
1 /*
2 * Copyright (C) 2013 Felix Fietkau <nbd@openwrt.org>
3 * Copyright (C) 2013 John Crispin <blogic@openwrt.org>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU Lesser General Public License version 2.1
7 * as published by the Free Software Foundation
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 */
14
15 #define _GNU_SOURCE
16 #include <sys/syscall.h>
17 #include <sys/mman.h>
18 #include <sys/utsname.h>
19
20 #include <stdlib.h>
21 #include <unistd.h>
22 #include <sys/syscall.h>
23 #include <sys/types.h>
24 #include <values.h>
25 #include <errno.h>
26 #include <stdio.h>
27 #include <string.h>
28 #include <sys/stat.h>
29 #include <fcntl.h>
30 #include <syslog.h>
31 #include <libgen.h>
32 #include <glob.h>
33 #include <elf.h>
34
35 #include <libubox/avl.h>
36 #include <libubox/avl-cmp.h>
37 #include <libubox/utils.h>
38
39 #define DEF_MOD_PATH "/lib/modules/%s/"
40
41 #define LOG(fmt, ...) do { \
42 syslog(LOG_INFO, fmt, ## __VA_ARGS__); \
43 printf("kmod: "fmt, ## __VA_ARGS__); \
44 } while (0)
45
46
47 enum {
48 SCANNED,
49 PROBE,
50 LOADED,
51 };
52
53 struct module {
54 struct avl_node avl;
55
56 char *name;
57 char *depends;
58
59 int size;
60 int usage;
61 int state;
62 int error;
63 };
64
65 static struct avl_tree modules;
66 static char *prefix = "";
67
68 static struct module *find_module(const char *name)
69 {
70 struct module *m;
71 return avl_find_element(&modules, name, m, avl);
72 }
73
74 static void free_modules(void)
75 {
76 struct module *m, *tmp;
77
78 avl_remove_all_elements(&modules, m, avl, tmp)
79 free(m);
80 }
81
82 static char* get_module_path(char *name)
83 {
84 static char path[256];
85 struct utsname ver;
86 struct stat s;
87
88 if (!stat(name, &s))
89 return name;
90
91 uname(&ver);
92 snprintf(path, 256, "%s" DEF_MOD_PATH "%s.ko", prefix, ver.release, name);
93
94 if (!stat(path, &s))
95 return path;
96
97 return NULL;
98 }
99
100 static char* get_module_name(char *path)
101 {
102 static char name[32];
103 char *t;
104
105 strncpy(name, basename(path), sizeof(name));
106
107 t = strstr(name, ".ko");
108 if (t)
109 *t = '\0';
110
111 return name;
112 }
113
114 #if __WORDSIZE == 64
115 static int elf_find_section(char *map, const char *section, unsigned int *offset, unsigned int *size)
116 {
117 const char *secnames;
118 Elf64_Ehdr *e;
119 Elf64_Shdr *sh;
120 int i;
121
122 e = (Elf64_Ehdr *) map;
123 sh = (Elf64_Shdr *) (map + e->e_shoff);
124
125 secnames = map + sh[e->e_shstrndx].sh_offset;
126 for (i = 0; i < e->e_shnum; i++) {
127 if (!strcmp(section, secnames + sh[i].sh_name)) {
128 *size = sh[i].sh_size;
129 *offset = sh[i].sh_offset;
130 return 0;
131 }
132 }
133
134 return -1;
135 }
136 #else
137 static int elf_find_section(char *map, const char *section, unsigned int *offset, unsigned int *size)
138 {
139 const char *secnames;
140 Elf32_Ehdr *e;
141 Elf32_Shdr *sh;
142 int i;
143
144 e = (Elf32_Ehdr *) map;
145 sh = (Elf32_Shdr *) (map + e->e_shoff);
146
147 secnames = map + sh[e->e_shstrndx].sh_offset;
148 for (i = 0; i < e->e_shnum; i++) {
149 if (!strcmp(section, secnames + sh[i].sh_name)) {
150 *size = sh[i].sh_size;
151 *offset = sh[i].sh_offset;
152 return 0;
153 }
154 }
155
156 return -1;
157 }
158 #endif
159
160 static struct module *
161 alloc_module(const char *name, const char *depends, int size)
162 {
163 struct module *m;
164 char *_name, *_dep;
165
166 m = calloc_a(sizeof(*m),
167 &_name, strlen(name) + 1,
168 &_dep, depends ? strlen(depends) + 2 : 0);
169 if (!m)
170 return NULL;
171
172 m->avl.key = m->name = strcpy(_name, name);
173
174 if (depends) {
175 m->depends = strcpy(_dep, depends);
176 while (*_dep) {
177 if (*_dep == ',')
178 *_dep = '\0';
179 _dep++;
180 }
181 }
182
183 m->size = size;
184 avl_insert(&modules, &m->avl);
185
186 return m;
187 }
188
189 static int scan_loaded_modules(void)
190 {
191 size_t buf_len = 0;
192 char *buf = NULL;
193 FILE *fp;
194
195 fp = fopen("/proc/modules", "r");
196 if (!fp) {
197 LOG("failed to open /proc/modules\n");
198 return -1;
199 }
200
201 while (getline(&buf, &buf_len, fp) > 0) {
202 struct module m;
203 struct module *n;
204
205 m.name = strtok(buf, " ");
206 m.size = atoi(strtok(NULL, " "));
207 m.usage = atoi(strtok(NULL, " "));
208 m.depends = strtok(NULL, " ");
209
210 if (!m.name || !m.depends)
211 continue;
212
213 n = alloc_module(m.name, m.depends, m.size);
214 n->usage = m.usage;
215 n->state = LOADED;
216 }
217 free(buf);
218 fclose(fp);
219
220 return 0;
221 }
222
223 static struct module* get_module_info(const char *module, const char *name)
224 {
225 int fd = open(module, O_RDONLY);
226 unsigned int offset, size;
227 char *map, *strings, *dep = NULL;
228 struct module *m;
229 struct stat s;
230
231 if (!fd) {
232 LOG("failed to open %s\n", module);
233 return NULL;
234 }
235
236 if (fstat(fd, &s) == -1) {
237 LOG("failed to stat %s\n", module);
238 return NULL;
239 }
240
241 map = mmap(NULL, s.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
242 if (map == MAP_FAILED) {
243 LOG("failed to mmap %s\n", module);
244 return NULL;
245 }
246
247 if (elf_find_section(map, ".modinfo", &offset, &size)) {
248 LOG("failed to load the .modinfo section from %s\n", module);
249 return NULL;
250 }
251
252 strings = map + offset;
253 while (strings && (strings < map + offset + size)) {
254 char *sep;
255 int len;
256
257 while (!strings[0])
258 strings++;
259 sep = strstr(strings, "=");
260 if (!sep)
261 break;
262 len = sep - strings;
263 sep++;
264 if (!strncmp(strings, "depends=", len + 1))
265 dep = sep;
266 strings = &sep[strlen(sep)];
267 }
268
269 m = alloc_module(name, dep, s.st_size);
270 if (!m)
271 return NULL;
272
273 m->state = SCANNED;
274
275 return m;
276 }
277
278 static int scan_module_folder(void)
279 {
280 int gl_flags = GLOB_NOESCAPE | GLOB_MARK;
281 struct utsname ver;
282 char *path;
283 glob_t gl;
284 int j;
285
286 uname(&ver);
287 path = alloca(sizeof(DEF_MOD_PATH "*.ko") + strlen(ver.release) + 1);
288 sprintf(path, DEF_MOD_PATH "*.ko", ver.release);
289
290 if (glob(path, gl_flags, NULL, &gl) < 0)
291 return -1;
292
293 for (j = 0; j < gl.gl_pathc; j++) {
294 char *name = get_module_name(gl.gl_pathv[j]);
295 struct module *m;
296
297 if (!name)
298 continue;
299
300 m = find_module(name);
301 if (!m)
302 get_module_info(gl.gl_pathv[j], name);
303 }
304
305 globfree(&gl);
306
307 return 0;
308 }
309
310 static int print_modinfo(char *module)
311 {
312 int fd = open(module, O_RDONLY);
313 unsigned int offset, size;
314 struct stat s;
315 char *map, *strings;
316
317 if (!fd) {
318 LOG("failed to open %s\n", module);
319 return -1;
320 }
321
322 if (fstat(fd, &s) == -1) {
323 LOG("failed to stat %s\n", module);
324 return -1;
325 }
326
327 map = mmap(NULL, s.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
328 if (map == MAP_FAILED) {
329 LOG("failed to mmap %s\n", module);
330 return -1;
331 }
332
333 if (elf_find_section(map, ".modinfo", &offset, &size)) {
334 LOG("failed to load the .modinfo section from %s\n", module);
335 return -1;
336 }
337
338 strings = map + offset;
339 printf("module:\t\t%s\n", module);
340 while (strings && (strings < map + offset + size)) {
341 char *dup = NULL;
342 char *sep;
343
344 while (!strings[0])
345 strings++;
346 sep = strstr(strings, "=");
347 if (!sep)
348 break;
349 dup = strndup(strings, sep - strings);
350 sep++;
351 if (strncmp(strings, "parm", 4)) {
352 if (strlen(dup) < 7)
353 printf("%s:\t\t%s\n", dup, sep);
354 else
355 printf("%s:\t%s\n", dup, sep);
356 }
357 strings = &sep[strlen(sep)];
358 if (dup)
359 free(dup);
360 }
361
362 return 0;
363 }
364
365 static int deps_available(struct module *m, int verbose)
366 {
367 char *dep;
368 int err = 0;
369
370 if (!strcmp(m->depends, "-") || !strcmp(m->depends, ""))
371 return 0;
372
373 dep = m->depends;
374
375 while (*dep) {
376 m = find_module(dep);
377
378 if (verbose && !m)
379 LOG("missing dependency %s\n", dep);
380 if (verbose && m && (m->state != LOADED))
381 LOG("dependency not loaded %s\n", dep);
382 if (!m || (m->state != LOADED))
383 err++;
384 dep += strlen(dep) + 1;
385 }
386
387 return err;
388 }
389
390 static int insert_module(char *path, const char *options)
391 {
392 void *data = 0;
393 struct stat s;
394 int fd, ret = -1;
395
396 if (stat(path, &s)) {
397 LOG("missing module %s\n", path);
398 return ret;
399 }
400
401 fd = open(path, O_RDONLY);
402 if (!fd) {
403 LOG("cannot open %s\n", path);
404 return ret;
405 }
406
407 data = malloc(s.st_size);
408 if (read(fd, data, s.st_size) == s.st_size)
409 ret = syscall(__NR_init_module, data, s.st_size, options);
410 else
411 LOG("failed to read full module %s\n", path);
412
413 close(fd);
414 free(data);
415
416 return ret;
417 }
418
419 static void load_moddeps(struct module *_m)
420 {
421 char *dep;
422 struct module *m;
423
424 if (!strcmp(_m->depends, "-") || !strcmp(_m->depends, ""))
425 return;
426
427 dep = _m->depends;
428
429 while (*dep) {
430 m = find_module(dep);
431
432 if (!m)
433 LOG("failed to find dependency %s\n", dep);
434 if (m && (m->state != LOADED)) {
435 m->state = PROBE;
436 load_moddeps(m);
437 }
438
439 dep = dep + strlen(dep) + 1;
440 }
441 }
442
443 static int iterations = 0;
444 static int load_modprobe(void)
445 {
446 int loaded, todo;
447 struct module *m;
448
449 avl_for_each_element(&modules, m, avl)
450 if (m->state == PROBE)
451 load_moddeps(m);
452
453 do {
454 loaded = 0;
455 todo = 0;
456 avl_for_each_element(&modules, m, avl) {
457 if ((m->state == PROBE) && (!deps_available(m, 0))) {
458 if (!insert_module(get_module_path(m->name), "")) {
459 m->state = LOADED;
460 m->error = 0;
461 loaded++;
462 continue;
463 }
464 m->error = 1;
465 }
466
467 if ((m->state == PROBE) || m->error)
468 todo++;
469 }
470 iterations++;
471 } while (loaded);
472
473 return todo;
474 }
475
476 static int print_insmod_usage(void)
477 {
478 LOG("Usage:\n\tinsmod filename [args]\n");
479
480 return -1;
481 }
482
483 static int print_usage(char *arg)
484 {
485 LOG("Usage:\n\t%s module\n", arg);
486
487 return -1;
488 }
489
490 static int main_insmod(int argc, char **argv)
491 {
492 char *name, *cur, *options;
493 int i, ret, len;
494
495 if (argc < 2)
496 return print_insmod_usage();
497
498 name = get_module_name(argv[1]);
499 if (!name) {
500 LOG("cannot find module - %s\n", argv[1]);
501 return -1;
502 }
503
504 if (scan_loaded_modules())
505 return -1;
506
507 if (find_module(name)) {
508 LOG("module is already loaded - %s\n", name);
509 return -1;
510
511 }
512
513 free_modules();
514
515 for (len = 0, i = 2; i < argc; i++)
516 len += strlen(argv[i]) + 1;
517
518 options = malloc(len);
519 options[0] = 0;
520 cur = options;
521 for (i = 2; i < argc; i++) {
522 if (options[0]) {
523 *cur = ' ';
524 cur++;
525 }
526 cur += sprintf(cur, "%s", argv[i]);
527 }
528
529 ret = insert_module(get_module_path(name), options);
530 free(options);
531
532 if (ret)
533 LOG("failed to insert %s\n", get_module_path(name));
534
535 return ret;
536 }
537
538 static int main_rmmod(int argc, char **argv)
539 {
540 struct module *m;
541 char *name;
542 int ret;
543
544 if (argc != 2)
545 return print_usage("rmmod");
546
547 if (scan_loaded_modules())
548 return -1;
549
550 name = get_module_name(argv[1]);
551 m = find_module(name);
552 if (!m) {
553 LOG("module is not loaded\n");
554 return -1;
555 }
556 ret = syscall(__NR_delete_module, m->name, 0);
557
558 if (ret)
559 LOG("unloading the module failed\n");
560
561 free_modules();
562
563 return ret;
564 }
565
566 static int main_lsmod(int argc, char **argv)
567 {
568 struct module *m;
569
570 if (scan_loaded_modules())
571 return -1;
572
573 avl_for_each_element(&modules, m, avl)
574 if (m->state == LOADED)
575 printf("%-20s%8d%3d %s\n",
576 m->name, m->size, m->usage,
577 (*m->depends == '-') ? ("") : (m->depends));
578
579 free_modules();
580
581 return 0;
582 }
583
584 static int main_modinfo(int argc, char **argv)
585 {
586 struct module *m;
587 char *name;
588
589 if (argc != 2)
590 return print_usage("modinfo");
591
592 if (scan_module_folder())
593 return -1;
594
595 name = get_module_name(argv[1]);
596 m = find_module(name);
597 if (!m) {
598 LOG("cannot find module - %s\n", argv[1]);
599 return -1;
600 }
601
602 name = get_module_path(m->name);
603 if (!name) {
604 LOG("cannot find path of module - %s\n", m->name);
605 return -1;
606 }
607
608 print_modinfo(name);
609
610 return 0;
611 }
612
613 static int main_modprobe(int argc, char **argv)
614 {
615 struct module *m;
616 char *name;
617
618 if (argc != 2)
619 return print_usage("modprobe");
620
621 if (scan_loaded_modules())
622 return -1;
623
624 if (scan_module_folder())
625 return -1;
626
627 name = get_module_name(argv[1]);
628 m = find_module(name);
629 if (m && m->state == LOADED) {
630 LOG("%s is already loaded\n", name);
631 return -1;
632 } else if (!m) {
633 LOG("failed to find a module named %s\n", name);
634 } else {
635 int fail;
636
637 m->state = PROBE;
638
639 fail = load_modprobe();
640
641 if (fail) {
642 LOG("%d module%s could not be probed\n",
643 fail, (fail == 1) ? ("") : ("s"));
644
645 avl_for_each_element(&modules, m, avl)
646 if ((m->state == PROBE) || m->error)
647 LOG("- %s\n", m->name);
648 }
649 }
650
651 free_modules();
652
653 return 0;
654 }
655
656 static int main_loader(int argc, char **argv)
657 {
658 int gl_flags = GLOB_NOESCAPE | GLOB_MARK;
659 char *dir = "/etc/modules.d/*";
660 struct module *m;
661 glob_t gl;
662 char *path;
663 int fail, j;
664
665 if (argc > 1)
666 dir = argv[1];
667
668 if (argc > 2)
669 prefix = argv[2];
670
671 path = malloc(strlen(dir) + 2);
672 strcpy(path, dir);
673 strcat(path, "*");
674
675 if (scan_loaded_modules())
676 return -1;
677
678 if (scan_module_folder())
679 return -1;
680
681 syslog(0, "kmodloader: loading kernel modules from %s\n", path);
682
683 if (glob(path, gl_flags, NULL, &gl) < 0)
684 goto out;
685
686 for (j = 0; j < gl.gl_pathc; j++) {
687 FILE *fp = fopen(gl.gl_pathv[j], "r");
688 size_t mod_len = 0;
689 char *mod = NULL;
690
691 if (!fp) {
692 LOG("failed to open %s\n", gl.gl_pathv[j]);
693 continue;
694 }
695
696 while (getline(&mod, &mod_len, fp) > 0) {
697 char *nl = strchr(mod, '\n');
698 struct module *m;
699 char *opts;
700
701 if (nl)
702 *nl = '\0';
703
704 opts = strchr(mod, ' ');
705 if (opts)
706 *opts++ = '\0';
707
708 m = find_module(get_module_name(mod));
709 if (!m || (m->state == LOADED))
710 continue;
711
712 m->state = PROBE;
713 if (basename(gl.gl_pathv[j])[0] - '0' <= 9)
714 load_modprobe();
715
716 }
717 free(mod);
718 fclose(fp);
719 }
720
721 fail = load_modprobe();
722 LOG("ran %d iterations\n", iterations);
723
724 if (fail) {
725 LOG("%d module%s could not be probed\n",
726 fail, (fail == 1) ? ("") : ("s"));
727
728 avl_for_each_element(&modules, m, avl)
729 if ((m->state == PROBE) || (m->error))
730 LOG("- %s - %d\n", m->name, deps_available(m, 1));
731 }
732
733 out:
734 globfree(&gl);
735 free(path);
736
737 return 0;
738 }
739
740 static int avl_modcmp(const void *k1, const void *k2, void *ptr)
741 {
742 const char *s1 = k1;
743 const char *s2 = k2;
744
745 while (*s1 && ((*s1 == *s2) ||
746 ((*s1 == '_') && (*s2 == '-')) ||
747 ((*s1 == '-') && (*s2 == '_'))))
748 {
749 s1++;
750 s2++;
751 }
752
753 return *(const unsigned char *)s1 - *(const unsigned char *)s2;
754 }
755
756 int main(int argc, char **argv)
757 {
758 char *exec = basename(*argv);
759
760 avl_init(&modules, avl_modcmp, false, NULL);
761 if (!strcmp(exec, "insmod"))
762 return main_insmod(argc, argv);
763
764 if (!strcmp(exec, "rmmod"))
765 return main_rmmod(argc, argv);
766
767 if (!strcmp(exec, "lsmod"))
768 return main_lsmod(argc, argv);
769
770 if (!strcmp(exec, "modinfo"))
771 return main_modinfo(argc, argv);
772
773 if (!strcmp(exec, "modprobe"))
774 return main_modprobe(argc, argv);
775
776 return main_loader(argc, argv);
777 }