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1 /*
2 * namedev.c
3 *
4 * Userspace devfs
5 *
6 * Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com>
7 *
8 *
9 * This program is free software; you can redistribute it and/or modify it
10 * under the terms of the GNU General Public License as published by the
11 * Free Software Foundation version 2 of the License.
12 *
13 * This program is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License along
19 * with this program; if not, write to the Free Software Foundation, Inc.,
20 * 675 Mass Ave, Cambridge, MA 02139, USA.
21 *
22 */
23
24 #include <stddef.h>
25 #include <stdlib.h>
26 #include <string.h>
27 #include <stdio.h>
28 #include <fcntl.h>
29 #include <ctype.h>
30 #include <unistd.h>
31 #include <errno.h>
32 #include <sys/wait.h>
33
34 #include "list.h"
35 #include "udev.h"
36 #include "udev_version.h"
37 #include "namedev.h"
38 #include "libsysfs/libsysfs.h"
39 #include "klibc_fixups.h"
40
41 LIST_HEAD(config_device_list);
42 LIST_HEAD(perm_device_list);
43
44 /* compare string with pattern (supports * ? [0-9] [!A-Z]) */
45 static int strcmp_pattern(const char *p, const char *s)
46 {
47 if (*s == '\0') {
48 while (*p == '*')
49 p++;
50 return (*p != '\0');
51 }
52 switch (*p) {
53 case '[':
54 {
55 int not = 0;
56 p++;
57 if (*p == '!') {
58 not = 1;
59 p++;
60 }
61 while (*p && (*p != ']')) {
62 int match = 0;
63 if (p[1] == '-') {
64 if ((*s >= *p) && (*s <= p[2]))
65 match = 1;
66 p += 3;
67 } else {
68 match = (*p == *s);
69 p++;
70 }
71 if (match ^ not) {
72 while (*p && (*p != ']'))
73 p++;
74 return strcmp_pattern(p+1, s+1);
75 }
76 }
77 }
78 break;
79 case '*':
80 if (strcmp_pattern(p, s+1))
81 return strcmp_pattern(p+1, s);
82 return 0;
83 case '\0':
84 if (*s == '\0') {
85 return 0;
86 }
87 break;
88 default:
89 if ((*p == *s) || (*p == '?'))
90 return strcmp_pattern(p+1, s+1);
91 break;
92 }
93 return 1;
94 }
95
96 #define copy_var(a, b, var) \
97 if (b->var) \
98 a->var = b->var;
99
100 #define copy_string(a, b, var) \
101 if (strlen(b->var)) \
102 strcpy(a->var, b->var);
103
104 int add_config_dev(struct config_device *new_dev)
105 {
106 struct list_head *tmp;
107 struct config_device *tmp_dev;
108
109 /* update the values if we already have the device */
110 list_for_each(tmp, &config_device_list) {
111 struct config_device *dev = list_entry(tmp, struct config_device, node);
112 if (strcmp_pattern(new_dev->name, dev->name))
113 continue;
114 if (strncmp(dev->bus, new_dev->bus, sizeof(dev->name)))
115 continue;
116 copy_var(dev, new_dev, type);
117 copy_string(dev, new_dev, bus);
118 copy_string(dev, new_dev, sysfs_file);
119 copy_string(dev, new_dev, sysfs_value);
120 copy_string(dev, new_dev, id);
121 copy_string(dev, new_dev, place);
122 copy_string(dev, new_dev, kernel_name);
123 copy_string(dev, new_dev, exec_program);
124 copy_string(dev, new_dev, symlink);
125 return 0;
126 }
127
128 /* not found, add new structure to the device list */
129 tmp_dev = malloc(sizeof(*tmp_dev));
130 if (!tmp_dev)
131 return -ENOMEM;
132 memcpy(tmp_dev, new_dev, sizeof(*tmp_dev));
133 list_add_tail(&tmp_dev->node, &config_device_list);
134 //dump_config_dev(tmp_dev);
135 return 0;
136 }
137
138 int add_perm_dev(struct perm_device *new_dev)
139 {
140 struct list_head *tmp;
141 struct perm_device *tmp_dev;
142
143 /* update the values if we already have the device */
144 list_for_each(tmp, &perm_device_list) {
145 struct perm_device *dev = list_entry(tmp, struct perm_device, node);
146 if (strcmp_pattern(new_dev->name, dev->name))
147 continue;
148 copy_var(dev, new_dev, mode);
149 copy_string(dev, new_dev, owner);
150 copy_string(dev, new_dev, group);
151 return 0;
152 }
153
154 /* not found, add new structure to the perm list */
155 tmp_dev = malloc(sizeof(*tmp_dev));
156 if (!tmp_dev)
157 return -ENOMEM;
158 memcpy(tmp_dev, new_dev, sizeof(*tmp_dev));
159 list_add_tail(&tmp_dev->node, &perm_device_list);
160 //dump_perm_dev(tmp_dev);
161 return 0;
162 }
163
164 static struct perm_device *find_perm(char *name)
165 {
166 struct list_head *tmp;
167 struct perm_device *perm = NULL;
168
169 list_for_each(tmp, &perm_device_list) {
170 perm = list_entry(tmp, struct perm_device, node);
171 if (strcmp_pattern(perm->name, name))
172 continue;
173 return perm;
174 }
175 return NULL;
176 }
177
178 static mode_t get_default_mode(struct sysfs_class_device *class_dev)
179 {
180 mode_t mode = 0600; /* default to owner rw only */
181
182 if (strlen(default_mode_str) != 0) {
183 mode = strtol(default_mode_str, NULL, 8);
184 }
185 return mode;
186 }
187
188 static void build_kernel_number(struct sysfs_class_device *class_dev, struct udevice *udev)
189 {
190 char *dig;
191
192 /* FIXME, figure out how to handle stuff like sdaj which will not work right now. */
193 dig = class_dev->name + strlen(class_dev->name);
194 while (isdigit(*(dig-1)))
195 dig--;
196 strfieldcpy(udev->kernel_number, dig);
197 dbg("kernel_number='%s'", udev->kernel_number);
198 }
199
200 static void apply_format(struct udevice *udev, unsigned char *string)
201 {
202 char name[NAME_SIZE];
203 char *pos;
204
205 while (1) {
206 pos = strchr(string, '%');
207
208 if (pos) {
209 strfieldcpy(name, pos+2);
210 *pos = 0x00;
211 switch (pos[1]) {
212 case 'b':
213 if (strlen(udev->bus_id) == 0)
214 break;
215 strcat(pos, udev->bus_id);
216 dbg("substitute bus_id '%s'", udev->bus_id);
217 break;
218 case 'n':
219 if (strlen(udev->kernel_number) == 0)
220 break;
221 strcat(pos, udev->kernel_number);
222 dbg("substitute kernel number '%s'", udev->kernel_number);
223 break;
224 case 'D':
225 if (strlen(udev->kernel_number) == 0) {
226 strcat(pos, "disk");
227 break;
228 }
229 strcat(pos, "part");
230 strcat(pos, udev->kernel_number);
231 dbg("substitute kernel number '%s'", udev->kernel_number);
232 break;
233 case 'm':
234 sprintf(pos, "%u", udev->minor);
235 dbg("substitute minor number '%u'", udev->minor);
236 break;
237 case 'M':
238 sprintf(pos, "%u", udev->major);
239 dbg("substitute major number '%u'", udev->major);
240 break;
241 case 'c':
242 if (strlen(udev->callout_value) == 0)
243 break;
244 strcat(pos, udev->callout_value);
245 dbg("substitute callout output '%s'", udev->callout_value);
246 break;
247 default:
248 dbg("unknown substitution type '%%%c'", pos[1]);
249 break;
250 }
251 strcat(string, name);
252 } else
253 break;
254 }
255 }
256
257
258 static int exec_callout(struct config_device *dev, char *value, int len)
259 {
260 int retval;
261 int res;
262 int status;
263 int fds[2];
264 pid_t pid;
265 int value_set = 0;
266 char buffer[256];
267 char *arg;
268 char *args[CALLOUT_MAXARG];
269 int i;
270
271 dbg("callout to '%s'", dev->exec_program);
272 retval = pipe(fds);
273 if (retval != 0) {
274 dbg("pipe failed");
275 return -1;
276 }
277 pid = fork();
278 if (pid == -1) {
279 dbg("fork failed");
280 return -1;
281 }
282
283 if (pid == 0) {
284 /* child */
285 close(STDOUT_FILENO);
286 dup(fds[1]); /* dup write side of pipe to STDOUT */
287 if (strchr(dev->exec_program, ' ')) {
288 /* callout with arguments */
289 arg = dev->exec_program;
290 for (i=0; i < CALLOUT_MAXARG-1; i++) {
291 args[i] = strsep(&arg, " ");
292 if (args[i] == NULL)
293 break;
294 }
295 if (args[i]) {
296 dbg("too many args - %d", i);
297 args[i] = NULL;
298 }
299 retval = execve(args[0], args, main_envp);
300 } else {
301 retval = execve(dev->exec_program, main_argv, main_envp);
302 }
303 if (retval != 0) {
304 dbg("child execve failed");
305 exit(1);
306 }
307 return -1; /* avoid compiler warning */
308 } else {
309 /* parent reads from fds[0] */
310 close(fds[1]);
311 retval = 0;
312 while (1) {
313 res = read(fds[0], buffer, sizeof(buffer) - 1);
314 if (res <= 0)
315 break;
316 buffer[res] = '\0';
317 if (res > len) {
318 dbg("callout len %d too short", len);
319 retval = -1;
320 }
321 if (value_set) {
322 dbg("callout value already set");
323 retval = -1;
324 } else {
325 value_set = 1;
326 strncpy(value, buffer, len);
327 }
328 }
329 dbg("callout returned '%s'", value);
330 close(fds[0]);
331 res = wait(&status);
332 if (res < 0) {
333 dbg("wait failed result %d", res);
334 retval = -1;
335 }
336
337 #ifndef __KLIBC__
338 if (!WIFEXITED(status) || (WEXITSTATUS(status) != 0)) {
339 dbg("callout program status 0x%x", status);
340 retval = -1;
341 }
342 #endif
343 }
344 return retval;
345 }
346
347 static int do_callout(struct sysfs_class_device *class_dev, struct udevice *udev, struct sysfs_device *sysfs_device)
348 {
349 struct config_device *dev;
350 struct list_head *tmp;
351
352 list_for_each(tmp, &config_device_list) {
353 dev = list_entry(tmp, struct config_device, node);
354 if (dev->type != CALLOUT)
355 continue;
356
357 if (sysfs_device) {
358 dbg("dev->bus='%s' sysfs_device->bus='%s'", dev->bus, sysfs_device->bus);
359 if (strcasecmp(dev->bus, sysfs_device->bus) != 0)
360 continue;
361 }
362
363 /* substitute anything that needs to be in the program name */
364 apply_format(udev, dev->exec_program);
365 if (exec_callout(dev, udev->callout_value, NAME_SIZE))
366 continue;
367 if (strcmp_pattern(dev->id, udev->callout_value) != 0)
368 continue;
369 strfieldcpy(udev->name, dev->name);
370 strfieldcpy(udev->symlink, dev->symlink);
371 dbg("callout returned matching value '%s', '%s' becomes '%s'",
372 dev->id, class_dev->name, udev->name);
373 return 0;
374 }
375 return -ENODEV;
376 }
377
378 static int do_label(struct sysfs_class_device *class_dev, struct udevice *udev, struct sysfs_device *sysfs_device)
379 {
380 struct sysfs_attribute *tmpattr = NULL;
381 struct config_device *dev;
382 struct list_head *tmp;
383 char *c;
384
385 list_for_each(tmp, &config_device_list) {
386 dev = list_entry(tmp, struct config_device, node);
387 if (dev->type != LABEL)
388 continue;
389
390 if (sysfs_device) {
391 dbg("dev->bus='%s' sysfs_device->bus='%s'", dev->bus, sysfs_device->bus);
392 if (strcasecmp(dev->bus, sysfs_device->bus) != 0)
393 continue;
394 }
395
396 dbg("look for device attribute '%s'", dev->sysfs_file);
397 /* try to find the attribute in the class device directory */
398 tmpattr = sysfs_get_classdev_attr(class_dev, dev->sysfs_file);
399 if (tmpattr)
400 goto label_found;
401
402 /* look in the class device directory if present */
403 if (sysfs_device) {
404 tmpattr = sysfs_get_device_attr(sysfs_device, dev->sysfs_file);
405 if (tmpattr)
406 goto label_found;
407 }
408
409 continue;
410
411 label_found:
412 c = tmpattr->value + strlen(tmpattr->value)-1;
413 if (*c == '\n')
414 *c = 0x00;
415 dbg("compare attribute '%s' value '%s' with '%s'",
416 dev->sysfs_file, tmpattr->value, dev->sysfs_value);
417 if (strcmp_pattern(dev->sysfs_value, tmpattr->value) != 0)
418 continue;
419
420 strfieldcpy(udev->name, dev->name);
421 strfieldcpy(udev->symlink, dev->symlink);
422 dbg("found matching attribute '%s', '%s' becomes '%s' ",
423 dev->sysfs_file, class_dev->name, udev->name);
424
425 return 0;
426 }
427 return -ENODEV;
428 }
429
430 static int do_number(struct sysfs_class_device *class_dev, struct udevice *udev, struct sysfs_device *sysfs_device)
431 {
432 struct config_device *dev;
433 struct list_head *tmp;
434 char path[SYSFS_PATH_MAX];
435 int found;
436 char *temp = NULL;
437
438 /* we have to have a sysfs device for NUMBER to work */
439 if (!sysfs_device)
440 return -ENODEV;
441
442 list_for_each(tmp, &config_device_list) {
443 dev = list_entry(tmp, struct config_device, node);
444 if (dev->type != NUMBER)
445 continue;
446
447 dbg("dev->bus='%s' sysfs_device->bus='%s'", dev->bus, sysfs_device->bus);
448 if (strcasecmp(dev->bus, sysfs_device->bus) != 0)
449 continue;
450
451 found = 0;
452 strfieldcpy(path, sysfs_device->path);
453 temp = strrchr(path, '/');
454 dbg("search '%s' in '%s', path='%s'", dev->id, temp, path);
455 if (strstr(temp, dev->id) != NULL) {
456 found = 1;
457 } else {
458 *temp = 0x00;
459 temp = strrchr(path, '/');
460 dbg("search '%s' in '%s', path='%s'", dev->id, temp, path);
461 if (strstr(temp, dev->id) != NULL)
462 found = 1;
463 }
464 if (!found)
465 continue;
466 strfieldcpy(udev->name, dev->name);
467 strfieldcpy(udev->symlink, dev->symlink);
468 dbg("found matching id '%s', '%s' becomes '%s'",
469 dev->id, class_dev->name, udev->name);
470 return 0;
471 }
472 return -ENODEV;
473 }
474
475 static int do_topology(struct sysfs_class_device *class_dev, struct udevice *udev, struct sysfs_device *sysfs_device)
476 {
477 struct config_device *dev;
478 struct list_head *tmp;
479 char path[SYSFS_PATH_MAX];
480 int found;
481 char *temp = NULL;
482
483 /* we have to have a sysfs device for TOPOLOGY to work */
484 if (!sysfs_device)
485 return -ENODEV;
486
487 list_for_each(tmp, &config_device_list) {
488 dev = list_entry(tmp, struct config_device, node);
489 if (dev->type != TOPOLOGY)
490 continue;
491
492 dbg("dev->bus='%s' sysfs_device->bus='%s'", dev->bus, sysfs_device->bus);
493 if (strcasecmp(dev->bus, sysfs_device->bus) != 0)
494 continue;
495
496 found = 0;
497 strfieldcpy(path, sysfs_device->path);
498 temp = strrchr(path, '/');
499 dbg("search '%s' in '%s', path='%s'", dev->place, temp, path);
500 if (strstr(temp, dev->place) != NULL) {
501 found = 1;
502 } else {
503 *temp = 0x00;
504 temp = strrchr(path, '/');
505 dbg("search '%s' in '%s', path='%s'", dev->place, temp, path);
506 if (strstr(temp, dev->place) != NULL)
507 found = 1;
508 }
509 if (!found)
510 continue;
511
512 strfieldcpy(udev->name, dev->name);
513 strfieldcpy(udev->symlink, dev->symlink);
514 dbg("found matching place '%s', '%s' becomes '%s'",
515 dev->place, class_dev->name, udev->name);
516 return 0;
517 }
518 return -ENODEV;
519 }
520
521 static int do_replace(struct sysfs_class_device *class_dev, struct udevice *udev, struct sysfs_device *sysfs_device)
522 {
523 struct config_device *dev;
524 struct list_head *tmp;
525
526 list_for_each(tmp, &config_device_list) {
527 dev = list_entry(tmp, struct config_device, node);
528 if (dev->type != REPLACE)
529 continue;
530
531 dbg("compare name '%s' with '%s'", dev->kernel_name, class_dev->name);
532 if (strcmp_pattern(dev->kernel_name, class_dev->name) != 0)
533 continue;
534
535 strfieldcpy(udev->name, dev->name);
536 strfieldcpy(udev->symlink, dev->symlink);
537 dbg("found name, '%s' becomes '%s'", dev->kernel_name, udev->name);
538
539 return 0;
540 }
541 return -ENODEV;
542 }
543
544 static void do_kernelname(struct sysfs_class_device *class_dev, struct udevice *udev)
545 {
546 /* heh, this is pretty simple... */
547 strfieldcpy(udev->name, class_dev->name);
548 }
549
550 int namedev_name_device(struct sysfs_class_device *class_dev, struct udevice *udev)
551 {
552 struct sysfs_device *sysfs_device = NULL;
553 struct sysfs_class_device *class_dev_parent = NULL;
554 int retval = 0;
555 char *temp = NULL;
556 struct perm_device *perm;
557
558 udev->mode = 0;
559
560 /* find the sysfs_device for this class device */
561 /* Wouldn't it really be nice if libsysfs could do this for us? */
562 if (class_dev->sysdevice) {
563 sysfs_device = class_dev->sysdevice;
564 } else {
565 /* bah, let's go backwards up a level to see if the device is there,
566 * as block partitions don't point to the physical device. Need to fix that
567 * up in the kernel...
568 */
569 if (strstr(class_dev->path, "block")) {
570 dbg("looking at block device");
571 if (isdigit(class_dev->path[strlen(class_dev->path)-1])) {
572 char path[SYSFS_PATH_MAX];
573
574 dbg("really is a partition");
575 strfieldcpy(path, class_dev->path);
576 temp = strrchr(path, '/');
577 *temp = 0x00;
578 dbg("looking for a class device at '%s'", path);
579 class_dev_parent = sysfs_open_class_device(path);
580 if (class_dev_parent == NULL) {
581 dbg("sysfs_open_class_device at '%s' failed", path);
582 } else {
583 dbg("class_dev_parent->name='%s'", class_dev_parent->name);
584 if (class_dev_parent->sysdevice)
585 sysfs_device = class_dev_parent->sysdevice;
586 }
587 }
588 }
589 }
590
591 if (sysfs_device) {
592 dbg("sysfs_device->path='%s'", sysfs_device->path);
593 dbg("sysfs_device->bus_id='%s'", sysfs_device->bus_id);
594 dbg("sysfs_device->bus='%s'", sysfs_device->bus);
595 strfieldcpy(udev->bus_id, sysfs_device->bus_id);
596 } else {
597 dbg("class_dev->name = '%s'", class_dev->name);
598 }
599
600 build_kernel_number(class_dev, udev);
601
602 /* rules are looked at in priority order */
603 retval = do_callout(class_dev, udev, sysfs_device);
604 if (retval == 0)
605 goto found;
606
607 retval = do_label(class_dev, udev, sysfs_device);
608 if (retval == 0)
609 goto found;
610
611 retval = do_number(class_dev, udev, sysfs_device);
612 if (retval == 0)
613 goto found;
614
615 retval = do_topology(class_dev, udev, sysfs_device);
616 if (retval == 0)
617 goto found;
618
619 retval = do_replace(class_dev, udev, sysfs_device);
620 if (retval == 0)
621 goto found;
622
623 do_kernelname(class_dev, udev);
624 goto done;
625
626 found:
627 /* substitute placeholder */
628 apply_format(udev, udev->name);
629 apply_format(udev, udev->symlink);
630
631 done:
632 perm = find_perm(udev->name);
633 if (perm) {
634 udev->mode = perm->mode;
635 strfieldcpy(udev->owner, perm->owner);
636 strfieldcpy(udev->group, perm->group);
637 } else {
638 /* no matching perms found :( */
639 udev->mode = get_default_mode(class_dev);
640 udev->owner[0] = 0x00;
641 udev->group[0] = 0x00;
642 }
643 dbg("name, '%s' is going to have owner='%s', group='%s', mode = %#o",
644 udev->name, udev->owner, udev->group, udev->mode);
645
646 if (class_dev_parent)
647 sysfs_close_class_device(class_dev_parent);
648
649 return 0;
650 }
651
652 int namedev_init(void)
653 {
654 int retval;
655
656 retval = namedev_init_rules();
657 if (retval)
658 return retval;
659
660 retval = namedev_init_permissions();
661 if (retval)
662 return retval;
663
664 dump_config_dev_list();
665 dump_perm_dev_list();
666 return retval;
667 }