chiark / gitweb /
09a299f22458a6cde5f4e06fa0e5e6ad9afb2afb
[elogind.git] / udev_rules.c
1 /*
2  * udev_rules.c
3  *
4  * Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com>
5  * Copyright (C) 2003-2005 Kay Sievers <kay.sievers@vrfy.org>
6  *
7  *      This program is free software; you can redistribute it and/or modify it
8  *      under the terms of the GNU General Public License as published by the
9  *      Free Software Foundation version 2 of the License.
10  * 
11  *      This program is distributed in the hope that it will be useful, but
12  *      WITHOUT ANY WARRANTY; without even the implied warranty of
13  *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  *      General Public License for more details.
15  * 
16  *      You should have received a copy of the GNU General Public License along
17  *      with this program; if not, write to the Free Software Foundation, Inc.,
18  *      675 Mass Ave, Cambridge, MA 02139, USA.
19  *
20  */
21
22 #include <stddef.h>
23 #include <stdlib.h>
24 #include <string.h>
25 #include <stdio.h>
26 #include <fcntl.h>
27 #include <ctype.h>
28 #include <unistd.h>
29 #include <errno.h>
30 #include <syslog.h>
31 #include <sys/wait.h>
32 #include <sys/stat.h>
33
34 #include "udev.h"
35 #include "udev_rules.h"
36
37
38 /* extract possible {attr} and move str behind it */
39 static char *get_format_attribute(char **str)
40 {
41         char *pos;
42         char *attr = NULL;
43
44         if (*str[0] == '{') {
45                 pos = strchr(*str, '}');
46                 if (pos == NULL) {
47                         err("missing closing brace for format");
48                         return NULL;
49                 }
50                 pos[0] = '\0';
51                 attr = *str+1;
52                 *str = pos+1;
53                 dbg("attribute='%s', str='%s'", attr, *str);
54         }
55         return attr;
56 }
57
58 /* extract possible format length and move str behind it*/
59 static int get_format_len(char **str)
60 {
61         int num;
62         char *tail;
63
64         if (isdigit(*str[0])) {
65                 num = (int) strtoul(*str, &tail, 10);
66                 if (num > 0) {
67                         *str = tail;
68                         dbg("format length=%i", num);
69                         return num;
70                 } else {
71                         err("format parsing error '%s'", *str);
72                 }
73         }
74         return -1;
75 }
76
77 static int get_key(char **line, char **key, char **value)
78 {
79         char *linepos;
80         char *temp;
81
82         linepos = *line;
83         if (!linepos)
84                 return -1;
85
86         if (strchr(linepos, '\\')) {
87                 dbg("escaped characters are not supported, skip");
88                 return -1;
89         }
90
91         /* skip whitespace */
92         while (isspace(linepos[0]))
93                 linepos++;
94
95         /* get the key */
96         *key = linepos;
97         while (1) {
98                 linepos++;
99                 if (linepos[0] == '\0')
100                         return -1;
101                 if (isspace(linepos[0]))
102                         break;
103                 if (linepos[0] == '=')
104                         break;
105         }
106
107         /* terminate key */
108         linepos[0] = '\0';
109         linepos++;
110
111         /* skip whitespace */
112         while (isspace(linepos[0]))
113                 linepos++;
114
115         /* get the value*/
116         if (linepos[0] == '"') {
117                 linepos++;
118                 temp = strchr(linepos, '"');
119                 if (!temp) {
120                         dbg("missing closing quote");
121                         return -1;
122                 }
123                 dbg("value is quoted");
124                 temp[0] = '\0';
125         } else if (linepos[0] == '\'') {
126                 linepos++;
127                 temp = strchr(linepos, '\'');
128                 if (!temp) {
129                         dbg("missing closing quote");
130                         return -1;
131                 }
132                 dbg("value is quoted");
133                 temp[0] = '\0';
134         } else if (linepos[0] == '\0') {
135                 dbg("value is empty");
136         } else {
137                 temp = linepos;
138                 while (temp[0] && !isspace(temp[0]))
139                         temp++;
140                 temp[0] = '\0';
141         }
142         *value = linepos;
143
144         return 0;
145 }
146
147 static int import_keys_into_env(struct udevice *udev, const char *buf, size_t bufsize)
148 {
149         char line[LINE_SIZE];
150         const char *bufline;
151         char *linepos;
152         char *variable;
153         char *value;
154         size_t cur;
155         size_t count;
156         int lineno;
157
158         /* loop through the whole buffer */
159         lineno = 0;
160         cur = 0;
161         while (cur < bufsize) {
162                 count = buf_get_line(buf, bufsize, cur);
163                 bufline = &buf[cur];
164                 cur += count+1;
165                 lineno++;
166
167                 if (count >= sizeof(line)) {
168                         err("line too long, conf line skipped %s, line %d", udev_config_filename, lineno);
169                         continue;
170                 }
171
172                 /* eat the whitespace */
173                 while ((count > 0) && isspace(bufline[0])) {
174                         bufline++;
175                         count--;
176                 }
177                 if (count == 0)
178                         continue;
179
180                 /* see if this is a comment */
181                 if (bufline[0] == COMMENT_CHARACTER)
182                         continue;
183
184                 memcpy(line, bufline, count);
185                 line[count] = '\0';
186
187                 linepos = line;
188                 if (get_key(&linepos, &variable, &value) == 0) {
189                         dbg("import '%s=%s'", variable, value);
190                         name_list_key_add(&udev->env_list, variable, value);
191                         setenv(variable, value, 1);
192                 }
193         }
194
195         return 0;
196 }
197
198 static int import_file_into_env(struct udevice *udev, const char *filename)
199 {
200         char *buf;
201         size_t bufsize;
202
203         if (file_map(filename, &buf, &bufsize) != 0) {
204                 err("can't open '%s': %s", filename, strerror(errno));
205                 return -1;
206         }
207         import_keys_into_env(udev, buf, bufsize);
208         file_unmap(buf, bufsize);
209
210         return 0;
211 }
212
213 static int import_program_into_env(struct udevice *udev, const char *program)
214 {
215         char result[1024];
216         size_t reslen;
217
218         if (run_program(program, udev->dev->subsystem, result, sizeof(result), &reslen, (udev_log_priority >= LOG_INFO)) != 0)
219                 return -1;
220         return import_keys_into_env(udev, result, reslen);
221 }
222
223 static int import_parent_into_env(struct udevice *udev, const char *filter)
224 {
225         struct sysfs_device *dev_parent;
226         int rc = -1;
227
228         dev_parent = sysfs_device_get_parent(udev->dev);
229         if (dev_parent != NULL) {
230                 struct udevice *udev_parent;
231                 struct name_entry *name_loop;
232
233                 dbg("found parent '%s', get the node name", dev_parent->devpath);
234                 udev_parent = udev_device_init();
235                 if (udev_parent == NULL)
236                         return -1;
237                 /* import the udev_db of the parent */
238                 if (udev_db_get_device(udev_parent, dev_parent->devpath) == 0) {
239                         dbg("import stored parent env '%s'", udev_parent->name);
240                         list_for_each_entry(name_loop, &udev_parent->env_list, node) {
241                                 char name[NAME_SIZE];
242                                 char *pos;
243
244                                 strlcpy(name, name_loop->name, sizeof(name));
245                                 pos = strchr(name, '=');
246                                 if (pos) {
247                                         pos[0] = '\0';
248                                         pos++;
249                                         if (strcmp_pattern(filter, name) == 0) {
250                                                 dbg("import key '%s'", name_loop->name);
251                                                 name_list_add(&udev->env_list, name_loop->name, 0);
252                                                 setenv(name, pos, 1);
253                                         } else
254                                                 dbg("skip key '%s'", name_loop->name);
255                                 }
256                         }
257                         rc = 0;
258                 } else
259                         dbg("parent not found in database");
260                 udev_device_cleanup(udev_parent);
261         }
262
263         return rc;
264 }
265
266 static int match_name_and_get_number(const char *base, const char *devname)
267 {
268         size_t baselen;
269         char *endptr;
270         int num;
271
272         baselen = strlen(base);
273         if (strncmp(base, devname, baselen) != 0)
274                 return -1;
275         if (devname[baselen] == '\0')
276                 return 0;
277         if (!isdigit(devname[baselen]))
278                 return -1;
279         num = strtoul(&devname[baselen], &endptr, 10);
280         if (endptr[0] != '\0')
281                 return -1;
282         return num;
283 }
284
285 /* finds the lowest positive device number such that <name>N isn't present in the udevdb
286  * if <name> doesn't exist, 0 is returned, N otherwise */
287 static int find_free_number(const char *base, const char *devpath)
288 {
289         char db_devpath[PATH_SIZE];
290         char filename[PATH_SIZE];
291         struct udevice *udev_db;
292         int num = 0;
293         static int warn = 1;
294
295         if (warn) {
296                 err("%%e is deprecated, will be removed and is unlikey to work correctly. Don't use it.");
297                 warn = 0;
298         }
299
300         /* check if the device already owns a matching name */
301         udev_db = udev_device_init();
302         if (udev_db == NULL)
303                 return -1;
304         if (udev_db_get_device(udev_db, devpath) == 0) {
305                 struct name_entry *name_loop;
306                 int devnum;
307
308                 devnum = match_name_and_get_number(base, udev_db->name);
309                 if (devnum >= 0) {
310                         num = devnum;
311                         dbg("device '%s', already has the node '%s' with num %u, use it", devpath, base, num);
312                         goto out;
313                 }
314                 list_for_each_entry(name_loop, &udev_db->symlink_list, node) {
315                         devnum = match_name_and_get_number(base, name_loop->name);
316                         if (devnum >= 0) {
317                                 num = devnum;
318                                 dbg("device '%s', already has a symlink '%s' with num %u, use it", devpath, base, num);
319                                 goto out;
320                         }
321                 }
322         }
323
324         /* just search the database again and again until a free name is found */
325         strlcpy(filename, base, sizeof(filename));
326         while (1) {
327                 dbg("look for existing node '%s'", filename);
328                 if (udev_db_lookup_name(filename, db_devpath, sizeof(db_devpath)) != 0) {
329                         dbg("free num=%d", num);
330                         break;
331                 }
332
333                 num++;
334                 if (num > 100000) {
335                         err("find_free_number aborted at num=%d", num);
336                         num = -1;
337                         break;
338                 }
339                 snprintf(filename, sizeof(filename), "%s%d", base, num);
340                 filename[sizeof(filename)-1] = '\0';
341         }
342
343 out:
344         udev_device_cleanup(udev_db);
345         return num;
346 }
347
348 #define WAIT_LOOP_PER_SECOND            50
349 static int wait_for_sysfs(struct udevice *udev, const char *file, int timeout)
350 {
351         char devicepath[PATH_SIZE];
352         char filepath[PATH_SIZE];
353         struct stat stats;
354         int loop = timeout * WAIT_LOOP_PER_SECOND;
355
356         strlcpy(devicepath, sysfs_path, sizeof(devicepath));
357         strlcat(devicepath, udev->dev->devpath, sizeof(devicepath));
358         strlcpy(filepath, devicepath, sizeof(filepath));
359         strlcat(filepath, "/", sizeof(filepath));
360         strlcat(filepath, file, sizeof(filepath));
361
362         dbg("will wait %i sec for '%s'", timeout, filepath);
363         while (--loop) {
364                 /* lookup file */
365                 if (stat(filepath, &stats) == 0) {
366                         info("file '%s' appeared after %i loops", filepath, (timeout * WAIT_LOOP_PER_SECOND) - loop-1);
367                         return 0;
368                 }
369                 /* make sure the device does not have disappeared in the meantime */
370                 if (stat(devicepath, &stats) != 0) {
371                         info("device disappeared while waiting for '%s'", filepath);
372                         return -2;
373                 }
374                 info("wait for '%s' for %i mseconds", filepath, 1000 / WAIT_LOOP_PER_SECOND);
375                 usleep(1000 * 1000 / WAIT_LOOP_PER_SECOND);
376         }
377         err("waiting for '%s' failed", filepath);
378         return -1;
379 }
380
381 void udev_rules_apply_format(struct udevice *udev, char *string, size_t maxsize)
382 {
383         char temp[PATH_SIZE];
384         char temp2[PATH_SIZE];
385         char *head, *tail, *pos, *cpos, *attr, *rest;
386         int len;
387         int i;
388         int count;
389         unsigned int next_free_number;
390         enum subst_type {
391                 SUBST_UNKNOWN,
392                 SUBST_DEVPATH,
393                 SUBST_KERNEL_NUMBER,
394                 SUBST_KERNEL_NAME,
395                 SUBST_ID,
396                 SUBST_MAJOR,
397                 SUBST_MINOR,
398                 SUBST_RESULT,
399                 SUBST_SYSFS,
400                 SUBST_ENUM,
401                 SUBST_PARENT,
402                 SUBST_TEMP_NODE,
403                 SUBST_ROOT,
404                 SUBST_MODALIAS,
405                 SUBST_ENV,
406         };
407         static const struct subst_map {
408                 char *name;
409                 char fmt;
410                 enum subst_type type;
411         } map[] = {
412                 { .name = "devpath",            .fmt = 'p',     .type = SUBST_DEVPATH },
413                 { .name = "number",             .fmt = 'n',     .type = SUBST_KERNEL_NUMBER },
414                 { .name = "kernel",             .fmt = 'k',     .type = SUBST_KERNEL_NAME },
415                 { .name = "id",                 .fmt = 'b',     .type = SUBST_ID },
416                 { .name = "major",              .fmt = 'M',     .type = SUBST_MAJOR },
417                 { .name = "minor",              .fmt = 'm',     .type = SUBST_MINOR },
418                 { .name = "result",             .fmt = 'c',     .type = SUBST_RESULT },
419                 { .name = "sysfs",              .fmt = 's',     .type = SUBST_SYSFS },
420                 { .name = "enum",               .fmt = 'e',     .type = SUBST_ENUM },
421                 { .name = "parent",             .fmt = 'P',     .type = SUBST_PARENT },
422                 { .name = "tempnode",           .fmt = 'N',     .type = SUBST_TEMP_NODE },
423                 { .name = "root",               .fmt = 'r',     .type = SUBST_ROOT },
424                 { .name = "modalias",           .fmt = 'A',     .type = SUBST_MODALIAS },
425                 { .name = "env",                .fmt = 'E',     .type = SUBST_ENV },
426                 { NULL, '\0', 0 }
427         };
428         enum subst_type type;
429         const struct subst_map *subst;
430
431         head = string;
432         while (1) {
433                 len = -1;
434                 while (head[0] != '\0') {
435                         if (head[0] == '$') {
436                                 /* substitute named variable */
437                                 if (head[1] == '\0')
438                                         break;
439                                 if (head[1] == '$') {
440                                         strlcpy(temp, head+2, sizeof(temp));
441                                         strlcpy(head+1, temp, maxsize);
442                                         head++;
443                                         continue;
444                                 }
445                                 head[0] = '\0';
446                                 for (subst = map; subst->name; subst++) {
447                                         if (strncasecmp(&head[1], subst->name, strlen(subst->name)) == 0) {
448                                                 type = subst->type;
449                                                 tail = head + strlen(subst->name)+1;
450                                                 dbg("will substitute format name '%s'", subst->name);
451                                                 goto found;
452                                         }
453                                 }
454                         }
455                         else if (head[0] == '%') {
456                                 /* substitute format char */
457                                 if (head[1] == '\0')
458                                         break;
459                                 if (head[1] == '%') {
460                                         strlcpy(temp, head+2, sizeof(temp));
461                                         strlcpy(head+1, temp, maxsize);
462                                         head++;
463                                         continue;
464                                 }
465                                 head[0] = '\0';
466                                 tail = head+1;
467                                 len = get_format_len(&tail);
468                                 for (subst = map; subst->name; subst++) {
469                                         if (tail[0] == subst->fmt) {
470                                                 type = subst->type;
471                                                 tail++;
472                                                 dbg("will substitute format char '%c'", subst->fmt);
473                                                 goto found;
474                                         }
475                                 }
476                         }
477                         head++;
478                 }
479                 break;
480 found:
481                 attr = get_format_attribute(&tail);
482                 strlcpy(temp, tail, sizeof(temp));
483                 dbg("format=%i, string='%s', tail='%s'", type ,string, tail);
484
485                 switch (type) {
486                 case SUBST_DEVPATH:
487                         strlcat(string, udev->dev->devpath, maxsize);
488                         dbg("substitute devpath '%s'", udev->dev->devpath);
489                         break;
490                 case SUBST_KERNEL_NAME:
491                         strlcat(string, udev->dev->kernel_name, maxsize);
492                         dbg("substitute kernel name '%s'", udev->dev->kernel_name);
493                         break;
494                 case SUBST_KERNEL_NUMBER:
495                         strlcat(string, udev->dev->kernel_number, maxsize);
496                         dbg("substitute kernel number '%s'", udev->dev->kernel_number);
497                         break;
498                 case SUBST_ID:
499                         if (udev->dev_parent != NULL) {
500                                 strlcat(string, udev->dev_parent->kernel_name, maxsize);
501                                 dbg("substitute id '%s'", udev->dev_parent->kernel_name);
502                         }
503                         break;
504                 case SUBST_MAJOR:
505                         sprintf(temp2, "%d", major(udev->devt));
506                         strlcat(string, temp2, maxsize);
507                         dbg("substitute major number '%s'", temp2);
508                         break;
509                 case SUBST_MINOR:
510                         sprintf(temp2, "%d", minor(udev->devt));
511                         strlcat(string, temp2, maxsize);
512                         dbg("substitute minor number '%s'", temp2);
513                         break;
514                 case SUBST_RESULT:
515                         if (udev->program_result[0] == '\0')
516                                 break;
517                         /* get part part of the result string */
518                         i = 0;
519                         if (attr != NULL)
520                                 i = strtoul(attr, &rest, 10);
521                         if (i > 0) {
522                                 dbg("request part #%d of result string", i);
523                                 cpos = udev->program_result;
524                                 while (--i) {
525                                         while (cpos[0] != '\0' && !isspace(cpos[0]))
526                                                 cpos++;
527                                         while (isspace(cpos[0]))
528                                                 cpos++;
529                                 }
530                                 if (i > 0) {
531                                         err("requested part of result string not found");
532                                         break;
533                                 }
534                                 strlcpy(temp2, cpos, sizeof(temp2));
535                                 /* %{2+}c copies the whole string from the second part on */
536                                 if (rest[0] != '+') {
537                                         cpos = strchr(temp2, ' ');
538                                         if (cpos)
539                                                 cpos[0] = '\0';
540                                 }
541                                 strlcat(string, temp2, maxsize);
542                                 dbg("substitute part of result string '%s'", temp2);
543                         } else {
544                                 strlcat(string, udev->program_result, maxsize);
545                                 dbg("substitute result string '%s'", udev->program_result);
546                         }
547                         break;
548                 case SUBST_SYSFS:
549                         if (attr == NULL) {
550                                 dbg("missing attribute");
551                                 break;
552                         } else {
553                                 struct sysfs_device *dev_parent;
554                                 const char *value;
555
556                                 dev_parent = udev->dev;
557                                 do {
558                                         dbg("looking at '%s'", dev_parent->devpath);
559                                         value = sysfs_attr_get_value(dev_parent->devpath, attr);
560                                         if (value != NULL) {
561                                                 strlcpy(temp2, value, sizeof(temp2));
562                                                 break;
563                                         }
564                                         dev_parent = sysfs_device_get_parent(dev_parent);
565                                 } while (dev_parent != NULL);
566
567                                 /* strip trailing whitespace of sysfs value */
568                                 i = strlen(temp2);
569                                 while (i > 0 && isspace(temp2[i-1]))
570                                         temp2[--i] = '\0';
571                                 count = replace_untrusted_chars(temp2);
572                                 if (count)
573                                         info("%i untrusted character(s) replaced" , count);
574                                 strlcat(string, temp2, maxsize);
575                                 dbg("substitute sysfs value '%s'", temp2);
576                         }
577                         break;
578                 case SUBST_ENUM:
579                         next_free_number = find_free_number(string, udev->dev->devpath);
580                         if (next_free_number > 0) {
581                                 sprintf(temp2, "%d", next_free_number);
582                                 strlcat(string, temp2, maxsize);
583                         }
584                         break;
585                 case SUBST_PARENT:
586                         {
587                                 struct sysfs_device *dev_parent;
588
589                                 dev_parent = sysfs_device_get_parent(udev->dev);
590                                 if (dev_parent != NULL) {
591                                         struct udevice *udev_parent;
592
593                                         dbg("found parent '%s', get the node name", dev_parent->devpath);
594                                         udev_parent = udev_device_init();
595                                         if (udev_parent != NULL) {
596                                                 /* lookup the name in the udev_db with the DEVPATH of the parent */
597                                                 if (udev_db_get_device(udev_parent, dev_parent->devpath) == 0) {
598                                                         strlcat(string, udev_parent->name, maxsize);
599                                                         dbg("substitute parent node name'%s'", udev_parent->name);
600                                                 } else
601                                                         dbg("parent not found in database");
602                                                 udev_device_cleanup(udev_parent);
603                                         }
604                                 }
605                         }
606                         break;
607                 case SUBST_TEMP_NODE:
608                         if (udev->tmp_node[0] == '\0') {
609                                 dbg("create temporary device node for callout");
610                                 snprintf(udev->tmp_node, sizeof(udev->tmp_node), "%s/.tmp-%u-%u",
611                                          udev_root, major(udev->devt), minor(udev->devt));
612                                 udev->tmp_node[sizeof(udev->tmp_node)-1] = '\0';
613                                 udev_node_mknod(udev, udev->tmp_node, udev->devt, 0600, 0, 0);
614                         }
615                         strlcat(string, udev->tmp_node, maxsize);
616                         dbg("substitute temporary device node name '%s'", udev->tmp_node);
617                         break;
618                 case SUBST_ROOT:
619                         strlcat(string, udev_root, maxsize);
620                         dbg("substitute udev_root '%s'", udev_root);
621                         break;
622                 case SUBST_MODALIAS:
623                         {
624                                 const char *value;
625                                 static int warn = 1;
626
627                                 if (warn) {
628                                         err("$modalias is deprecated, use $env{MODALIAS} or "
629                                             "$sysfs{modalias} instead.");
630                                         warn = 0;
631                                 }
632
633                                 value = sysfs_attr_get_value(udev->dev->devpath, "modalias");
634                                 if (value != NULL) {
635                                         strlcat(string, value, maxsize);
636                                         dbg("substitute MODALIAS '%s'", temp2);
637                                 }
638                         }
639                         break;
640                 case SUBST_ENV:
641                         if (attr == NULL) {
642                                 dbg("missing attribute");
643                                 break;
644                         }
645                         pos = getenv(attr);
646                         if (pos == NULL) {
647                                 dbg("env '%s' not available", attr);
648                                 break;
649                         }
650                         dbg("substitute env '%s=%s'", attr, pos);
651                         strlcat(string, pos, maxsize);
652                         break;
653                 default:
654                         err("unknown substitution type=%i", type);
655                         break;
656                 }
657                 /* possibly truncate to format-char specified length */
658                 if (len != -1) {
659                         head[len] = '\0';
660                         dbg("truncate to %i chars, subtitution string becomes '%s'", len, head);
661                 }
662                 strlcat(string, temp, maxsize);
663         }
664 }
665
666 static char *key_val(struct udev_rule *rule, struct key *key)
667 {
668         return rule->buf + key->val_off;
669 }
670
671 static char *key_pair_name(struct udev_rule *rule, struct key_pair *pair)
672 {
673         return rule->buf + pair->key_name_off;
674 }
675
676 static int match_key(const char *key_name, struct udev_rule *rule, struct key *key, const char *val)
677 {
678         int match;
679         char value[PATH_SIZE];
680         char *key_value;
681         char *pos;
682
683         if (key->operation == KEY_OP_UNSET)
684                 return 0;
685
686         strlcpy(value, rule->buf + key->val_off, sizeof(value));
687         key_value = value;
688
689         dbg("key %s value='%s'", key_name, key_value);
690         while (key_value) {
691                 pos = strchr(key_value, '|');
692                 if (pos) {
693                         pos[0] = '\0';
694                         pos++;
695                 }
696                 dbg("match %s '%s' <-> '%s'", key_name, key_value, val);
697                 match = (strcmp_pattern(key_value, val) == 0);
698                 if (match && (key->operation != KEY_OP_NOMATCH)) {
699                         dbg("%s is true (matching value)", key_name);
700                         return 0;
701                 }
702                 if (!match && (key->operation == KEY_OP_NOMATCH)) {
703                         dbg("%s is true (non-matching value)", key_name);
704                         return 0;
705                 }
706                 key_value = pos;
707         }
708         dbg("%s is false", key_name);
709         return -1;
710 }
711
712 /* match a single rule against a given device and possibly its parent devices */
713 static int match_rule(struct udevice *udev, struct udev_rule *rule)
714 {
715         int i;
716
717         if (match_key("ACTION", rule, &rule->action, udev->action))
718                 goto nomatch;
719
720         if (match_key("KERNEL", rule, &rule->kernel_name, udev->dev->kernel_name))
721                 goto nomatch;
722
723         if (match_key("SUBSYSTEM", rule, &rule->subsystem, udev->dev->subsystem))
724                 goto nomatch;
725
726         if (match_key("DEVPATH", rule, &rule->devpath, udev->dev->devpath))
727                 goto nomatch;
728
729         if (rule->modalias.operation != KEY_OP_UNSET) {
730                 const char *value;
731                 static int warn = 1;
732
733                 if (warn) {
734                         err("MODALIAS is deprecated, use ENV{MODALIAS} or SYSFS{modalias} instead.");
735                         warn = 0;
736                 }
737
738                 value = sysfs_attr_get_value(udev->dev->devpath, "modalias");
739                 if (value == NULL) {
740                         dbg("MODALIAS value not found");
741                         goto nomatch;
742                 }
743                 if (match_key("MODALIAS", rule, &rule->modalias, value))
744                         goto nomatch;
745         }
746
747         for (i = 0; i < rule->env.count; i++) {
748                 struct key_pair *pair = &rule->env.keys[i];
749
750                 /* we only check for matches, assignments will be handled later */
751                 if (pair->key.operation != KEY_OP_ASSIGN) {
752                         const char *key_name = key_pair_name(rule, pair);
753                         const char *value = getenv(key_name);
754
755                         if (!value) {
756                                 dbg("ENV{'%s'} is not set, treat as empty", key_name);
757                                 value = "";
758                         }
759                         if (match_key("ENV", rule, &pair->key, value))
760                                 goto nomatch;
761                 }
762         }
763
764         if (rule->wait_for_sysfs.operation != KEY_OP_UNSET) {
765                 int found;
766
767                 found = (wait_for_sysfs(udev, key_val(rule, &rule->wait_for_sysfs), 3) == 0);
768                 if (!found && (rule->wait_for_sysfs.operation != KEY_OP_NOMATCH)) {
769                         dbg("WAIT_FOR_SYSFS failed");
770                         goto nomatch;
771                 }
772         }
773
774         /* walk up the chain of parent devices and find a match */
775         udev->dev_parent = udev->dev;
776         while (1) {
777                 /* check for matching driver */
778                 if (rule->driver.operation != KEY_OP_UNSET) {
779                         if (match_key("DRIVER", rule, &rule->driver, udev->dev_parent->driver))
780                                 goto try_parent;
781                 }
782
783                 /* check for matching subsystem/bus value */
784                 if (rule->bus.operation != KEY_OP_UNSET) {
785                         if (match_key("BUS", rule, &rule->bus, udev->dev_parent->subsystem))
786                                 goto try_parent;
787                 }
788
789                 /* check for matching bus id (device name) */
790                 if (rule->id.operation != KEY_OP_UNSET) {
791                         if (match_key("ID", rule, &rule->id, udev->dev_parent->kernel_name))
792                                 goto try_parent;
793                 }
794
795                 /* check for matching sysfs pairs */
796                 if (rule->sysfs.count) {
797                         dbg("check %i SYSFS keys", rule->sysfs.count);
798                         for (i = 0; i < rule->sysfs.count; i++) {
799                                 struct key_pair *pair = &rule->sysfs.keys[i];
800                                 const char *key_name = key_pair_name(rule, pair);
801                                 const char *key_value = key_val(rule, &pair->key);
802                                 const char *value;
803                                 char val[VALUE_SIZE];
804                                 size_t len;
805
806                                 value = sysfs_attr_get_value(udev->dev_parent->devpath, key_name);
807                                 if (value == NULL)
808                                         value = sysfs_attr_get_value(udev->dev->devpath, key_name);
809                                 if (value == NULL)
810                                         goto try_parent;
811                                 strlcpy(val, value, sizeof(val));
812
813                                 /* strip trailing whitespace of value, if not asked to match for it */
814                                 len = strlen(key_value);
815                                 if (len > 0 && !isspace(key_value[len-1])) {
816                                         len = strlen(val);
817                                         while (len > 0 && isspace(val[len-1]))
818                                                 val[--len] = '\0';
819                                         dbg("removed %zi trailing whitespace chars from '%s'", strlen(val)-len, val);
820                                 }
821
822                                 if (match_key("SYSFS", rule, &pair->key, val))
823                                         goto try_parent;
824                         }
825                         dbg("all %i SYSFS keys matched", rule->sysfs.count);
826                 }
827
828                 /* found matching device  */
829                 break;
830 try_parent:
831                 /* move to parent device */
832                 dbg("try parent sysfs device");
833                 udev->dev_parent = sysfs_device_get_parent(udev->dev_parent);
834                 if (udev->dev_parent == NULL)
835                         goto nomatch;
836                 dbg("looking at dev_parent->devpath='%s'", udev->dev_parent->devpath);
837                 dbg("looking at dev_parent->bus_kernel_name='%s'", udev->dev_parent->kernel_name);
838         }
839
840         /* execute external program */
841         if (rule->program.operation != KEY_OP_UNSET) {
842                 char program[PATH_SIZE];
843                 char result[PATH_SIZE];
844
845                 strlcpy(program, key_val(rule, &rule->program), sizeof(program));
846                 udev_rules_apply_format(udev, program, sizeof(program));
847                 if (run_program(program, udev->dev->subsystem, result, sizeof(result), NULL, (udev_log_priority >= LOG_INFO)) != 0) {
848                         dbg("PROGRAM is false");
849                         udev->program_result[0] = '\0';
850                         if (rule->program.operation != KEY_OP_NOMATCH)
851                                 goto nomatch;
852                 } else {
853                         int count;
854
855                         dbg("PROGRAM matches");
856                         remove_trailing_chars(result, '\n');
857                         count = replace_untrusted_chars(result);
858                         if (count)
859                                 info("%i untrusted character(s) replaced" , count);
860                         dbg("result is '%s'", result);
861                         strlcpy(udev->program_result, result, sizeof(udev->program_result));
862                         dbg("PROGRAM returned successful");
863                         if (rule->program.operation == KEY_OP_NOMATCH)
864                                 goto nomatch;
865                 }
866                 dbg("PROGRAM key is true");
867         }
868
869         /* check for matching result of external program */
870         if (match_key("RESULT", rule, &rule->result, udev->program_result))
871                 goto nomatch;
872
873         /* import variables returned from program or or file into environment */
874         if (rule->import.operation != KEY_OP_UNSET) {
875                 char import[PATH_SIZE];
876                 int rc = -1;
877
878                 strlcpy(import, key_val(rule, &rule->import), sizeof(import));
879                 udev_rules_apply_format(udev, import, sizeof(import));
880                 dbg("check for IMPORT import='%s'", import);
881                 if (rule->import_type == IMPORT_PROGRAM) {
882                         rc = import_program_into_env(udev, import);
883                 } else if (rule->import_type == IMPORT_FILE) {
884                         dbg("import file import='%s'", import);
885                         rc = import_file_into_env(udev, import);
886                 } else if (rule->import_type == IMPORT_PARENT) {
887                         dbg("import parent import='%s'", import);
888                         rc = import_parent_into_env(udev, import);
889                 }
890                 if (rc != 0) {
891                         dbg("IMPORT failed");
892                         if (rule->import.operation != KEY_OP_NOMATCH)
893                                 goto nomatch;
894                 } else
895                         dbg("IMPORT '%s' imported", key_val(rule, &rule->import));
896                 dbg("IMPORT key is true");
897         }
898
899         /* rule matches, if we have ENV assignments export it */
900         for (i = 0; i < rule->env.count; i++) {
901                 struct key_pair *pair = &rule->env.keys[i];
902
903                 if (pair->key.operation == KEY_OP_ASSIGN) {
904                         const char *key_name = key_pair_name(rule, pair);
905                         const char *value = key_val(rule, &pair->key);
906
907                         name_list_key_add(&udev->env_list, key_name, value);
908                         setenv(key_name, value, 1);
909                         dbg("export ENV '%s=%s'", key_name, value);
910                 }
911         }
912
913         return 0;
914
915 nomatch:
916         return -1;
917 }
918
919 int udev_rules_get_name(struct udev_rules *rules, struct udevice *udev)
920 {
921         struct udev_rule *rule;
922         int name_set = 0;
923
924         dbg("udev->dev->devpath='%s'", udev->dev->devpath);
925         dbg("udev->dev->kernel_name='%s'", udev->dev->kernel_name);
926
927         /* look for a matching rule to apply */
928         udev_rules_iter_init(rules);
929         while (1) {
930                 rule = udev_rules_iter_next(rules);
931                 if (rule == NULL)
932                         break;
933
934                 if (name_set && rule->name.operation != KEY_OP_UNSET) {
935                         dbg("node name already set, rule ignored");
936                         continue;
937                 }
938
939                 dbg("process rule");
940                 if (match_rule(udev, rule) == 0) {
941                         /* apply options */
942                         if (rule->ignore_device) {
943                                 info("rule applied, '%s' is ignored", udev->dev->kernel_name);
944                                 udev->ignore_device = 1;
945                                 return 0;
946                         }
947                         if (rule->ignore_remove) {
948                                 udev->ignore_remove = 1;
949                                 dbg("remove event should be ignored");
950                         }
951                         /* apply all_partitions option only at a main block device */
952                         if (rule->partitions &&
953                             strcmp(udev->dev->subsystem, "block") == 0 && udev->dev->kernel_number[0] == '\0') {
954                                 udev->partitions = rule->partitions;
955                                 dbg("creation of partition nodes requested");
956                         }
957
958                         /* apply permissions */
959                         if (!udev->mode_final && rule->mode != 0000) {
960                                 if (rule->mode_operation == KEY_OP_ASSIGN_FINAL)
961                                         udev->mode_final = 1;
962                                 udev->mode = rule->mode;
963                                 dbg("applied mode=%#o to '%s'", rule->mode, udev->dev->kernel_name);
964                         }
965                         if (!udev->owner_final && rule->owner.operation != KEY_OP_UNSET) {
966                                 if (rule->owner.operation == KEY_OP_ASSIGN_FINAL)
967                                         udev->owner_final = 1;
968                                 strlcpy(udev->owner, key_val(rule, &rule->owner), sizeof(udev->owner));
969                                 udev_rules_apply_format(udev, udev->owner, sizeof(udev->owner));
970                                 dbg("applied owner='%s' to '%s'", udev->owner, udev->dev->kernel_name);
971                         }
972                         if (!udev->group_final && rule->group.operation != KEY_OP_UNSET) {
973                                 if (rule->group.operation == KEY_OP_ASSIGN_FINAL)
974                                         udev->group_final = 1;
975                                 strlcpy(udev->group, key_val(rule, &rule->group), sizeof(udev->group));
976                                 udev_rules_apply_format(udev, udev->group, sizeof(udev->group));
977                                 dbg("applied group='%s' to '%s'", udev->group, udev->dev->kernel_name);
978                         }
979
980                         /* collect symlinks */
981                         if (!udev->symlink_final && rule->symlink.operation != KEY_OP_UNSET) {
982                                 char temp[PATH_SIZE];
983                                 char *pos, *next;
984                                 int count;
985
986                                 if (rule->symlink.operation == KEY_OP_ASSIGN_FINAL)
987                                         udev->symlink_final = 1;
988                                 if (rule->symlink.operation == KEY_OP_ASSIGN || rule->symlink.operation == KEY_OP_ASSIGN_FINAL) {
989                                         info("reset symlink list");
990                                         name_list_cleanup(&udev->symlink_list);
991                                 }
992                                 strlcpy(temp, key_val(rule, &rule->symlink), sizeof(temp));
993                                 udev_rules_apply_format(udev, temp, sizeof(temp));
994                                 count = replace_untrusted_chars(temp);
995                                 if (count)
996                                         info("%i untrusted character(s) replaced" , count);
997                                 dbg("rule applied, added symlink(s) '%s'", temp);
998
999                                 /* add multiple symlinks separated by spaces */
1000                                 pos = temp;
1001                                 while (isspace(pos[0]))
1002                                         pos++;
1003                                 next = strchr(pos, ' ');
1004                                 while (next) {
1005                                         next[0] = '\0';
1006                                         info("add symlink '%s'", pos);
1007                                         name_list_add(&udev->symlink_list, pos, 0);
1008                                         while (isspace(next[1]))
1009                                                 next++;
1010                                         pos = &next[1];
1011                                         next = strchr(pos, ' ');
1012                                 }
1013                                 if (pos[0] != '\0') {
1014                                         info("add symlink '%s'", pos);
1015                                         name_list_add(&udev->symlink_list, pos, 0);
1016                                 }
1017                         }
1018
1019                         /* set name, later rules with name set will be ignored */
1020                         if (rule->name.operation != KEY_OP_UNSET) {
1021                                 int count;
1022
1023                                 name_set = 1;
1024                                 strlcpy(udev->name, key_val(rule, &rule->name), sizeof(udev->name));
1025                                 udev_rules_apply_format(udev, udev->name, sizeof(udev->name));
1026                                 count = replace_untrusted_chars(udev->name);
1027                                 if (count)
1028                                         info("%i untrusted character(s) replaced", count);
1029
1030                                 info("rule applied, '%s' becomes '%s'", udev->dev->kernel_name, udev->name);
1031                                 if (strcmp(udev->dev->subsystem, "net") != 0)
1032                                         dbg("name, '%s' is going to have owner='%s', group='%s', mode=%#o partitions=%i",
1033                                             udev->name, udev->owner, udev->group, udev->mode, udev->partitions);
1034                         }
1035
1036                         if (!udev->run_final && rule->run.operation != KEY_OP_UNSET) {
1037                                 if (rule->run.operation == KEY_OP_ASSIGN_FINAL)
1038                                         udev->run_final = 1;
1039                                 if (rule->run.operation == KEY_OP_ASSIGN || rule->run.operation == KEY_OP_ASSIGN_FINAL) {
1040                                         info("reset run list");
1041                                         name_list_cleanup(&udev->run_list);
1042                                 }
1043                                 dbg("add run '%s'", key_val(rule, &rule->run));
1044                                 name_list_add(&udev->run_list, key_val(rule, &rule->run), 0);
1045                         }
1046
1047                         if (rule->last_rule) {
1048                                 dbg("last rule to be applied");
1049                                 break;
1050                         }
1051
1052                         if (rule->goto_label.operation != KEY_OP_UNSET) {
1053                                 dbg("moving forward to label '%s'", key_val(rule, &rule->goto_label));
1054                                 udev_rules_iter_label(rules, key_val(rule, &rule->goto_label));
1055                         }
1056                 }
1057         }
1058
1059         if (!name_set) {
1060                 strlcpy(udev->name, udev->dev->kernel_name, sizeof(udev->name));
1061                 info("no node name set, will use kernel name '%s'", udev->name);
1062         }
1063
1064         if (udev->tmp_node[0] != '\0') {
1065                 dbg("removing temporary device node");
1066                 unlink_secure(udev->tmp_node);
1067                 udev->tmp_node[0] = '\0';
1068         }
1069
1070         return 0;
1071 }
1072
1073 int udev_rules_get_run(struct udev_rules *rules, struct udevice *udev)
1074 {
1075         struct udev_rule *rule;
1076
1077         dbg("udev->kernel_name='%s'", udev->dev->kernel_name);
1078
1079         /* look for a matching rule to apply */
1080         udev_rules_iter_init(rules);
1081         while (1) {
1082                 rule = udev_rules_iter_next(rules);
1083                 if (rule == NULL)
1084                         break;
1085
1086                 dbg("process rule");
1087                 if (rule->name.operation != KEY_OP_UNSET || rule->symlink.operation != KEY_OP_UNSET ||
1088                     rule->mode_operation != KEY_OP_UNSET || rule->owner.operation != KEY_OP_UNSET || rule->group.operation != KEY_OP_UNSET) {
1089                         dbg("skip rule that names a device");
1090                         continue;
1091                 }
1092
1093                 if (match_rule(udev, rule) == 0) {
1094                         if (rule->ignore_device) {
1095                                 info("rule applied, '%s' is ignored", udev->dev->kernel_name);
1096                                 udev->ignore_device = 1;
1097                                 return 0;
1098                         }
1099
1100                         if (!udev->run_final && rule->run.operation != KEY_OP_UNSET) {
1101                                 if (rule->run.operation == KEY_OP_ASSIGN || rule->run.operation == KEY_OP_ASSIGN_FINAL) {
1102                                         info("reset run list");
1103                                         name_list_cleanup(&udev->run_list);
1104                                 }
1105                                 dbg("add run '%s'", key_val(rule, &rule->run));
1106                                 name_list_add(&udev->run_list, key_val(rule, &rule->run), 0);
1107                                 if (rule->run.operation == KEY_OP_ASSIGN_FINAL)
1108                                         break;
1109                         }
1110
1111                         if (rule->last_rule) {
1112                                 dbg("last rule to be applied");
1113                                 break;
1114                         }
1115
1116                         if (rule->goto_label.operation != KEY_OP_UNSET) {
1117                                 dbg("moving forward to label '%s'", key_val(rule, &rule->goto_label));
1118                                 udev_rules_iter_label(rules, key_val(rule, &rule->goto_label));
1119                         }
1120                 }
1121         }
1122
1123         return 0;
1124 }