udev_rules.c

   1 /*
   2  * udev_rules.c
   3  *
   4  * Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com>
   5  * Copyright (C) 2003-2006 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 #define WAIT_LOOP_PER_SECOND            50
 267 static int wait_for_sysfs(struct udevice *udev, const char *file, int timeout)
 268 {
 269         char devicepath[PATH_SIZE];
 270         char filepath[PATH_SIZE];
 271         struct stat stats;
 272         int loop = timeout * WAIT_LOOP_PER_SECOND;
 273
 274         strlcpy(devicepath, sysfs_path, sizeof(devicepath));
 275         strlcat(devicepath, udev->dev->devpath, sizeof(devicepath));
 276         strlcpy(filepath, devicepath, sizeof(filepath));
 277         strlcat(filepath, "/", sizeof(filepath));
 278         strlcat(filepath, file, sizeof(filepath));
 279
 280         dbg("will wait %i sec for '%s'", timeout, filepath);
 281         while (--loop) {
 282                 /* lookup file */
 283                 if (stat(filepath, &stats) == 0) {
 284                         info("file '%s' appeared after %i loops", filepath, (timeout * WAIT_LOOP_PER_SECOND) - loop-1);
 285                         return 0;
 286                 }
 287                 /* make sure the device does not have disappeared in the meantime */
 288                 if (stat(devicepath, &stats) != 0) {
 289                         info("device disappeared while waiting for '%s'", filepath);
 290                         return -2;
 291                 }
 292                 info("wait for '%s' for %i mseconds", filepath, 1000 / WAIT_LOOP_PER_SECOND);
 293                 usleep(1000 * 1000 / WAIT_LOOP_PER_SECOND);
 294         }
 295         err("waiting for '%s' failed", filepath);
 296         return -1;
 297 }
 298
 299 void udev_rules_apply_format(struct udevice *udev, char *string, size_t maxsize)
 300 {
 301         char temp[PATH_SIZE];
 302         char temp2[PATH_SIZE];
 303         char *head, *tail, *pos, *cpos, *attr, *rest;
 304         int len;
 305         int i;
 306         int count;
 307         enum subst_type {
 308                 SUBST_UNKNOWN,
 309                 SUBST_DEVPATH,
 310                 SUBST_KERNEL,
 311                 SUBST_KERNEL_NUMBER,
 312                 SUBST_ID,
 313                 SUBST_MAJOR,
 314                 SUBST_MINOR,
 315                 SUBST_RESULT,
 316                 SUBST_ATTR,
 317                 SUBST_PARENT,
 318                 SUBST_TEMP_NODE,
 319                 SUBST_ROOT,
 320                 SUBST_ENV,
 321         };
 322         static const struct subst_map {
 323                 char *name;
 324                 char fmt;
 325                 enum subst_type type;
 326         } map[] = {
 327                 { .name = "devpath",    .fmt = 'p',     .type = SUBST_DEVPATH },
 328                 { .name = "number",     .fmt = 'n',     .type = SUBST_KERNEL_NUMBER },
 329                 { .name = "kernel",     .fmt = 'k',     .type = SUBST_KERNEL },
 330                 { .name = "id",         .fmt = 'b',     .type = SUBST_ID },
 331                 { .name = "major",      .fmt = 'M',     .type = SUBST_MAJOR },
 332                 { .name = "minor",      .fmt = 'm',     .type = SUBST_MINOR },
 333                 { .name = "result",     .fmt = 'c',     .type = SUBST_RESULT },
 334                 { .name = "attr",       .fmt = 's',     .type = SUBST_ATTR },
 335                 { .name = "sysfs",      .fmt = 's',     .type = SUBST_ATTR },
 336                 { .name = "parent",     .fmt = 'P',     .type = SUBST_PARENT },
 337                 { .name = "tempnode",   .fmt = 'N',     .type = SUBST_TEMP_NODE },
 338                 { .name = "root",       .fmt = 'r',     .type = SUBST_ROOT },
 339                 { .name = "env",        .fmt = 'E',     .type = SUBST_ENV },
 340                 { NULL, '\0', 0 }
 341         };
 342         enum subst_type type;
 343         const struct subst_map *subst;
 344
 345         head = string;
 346         while (1) {
 347                 len = -1;
 348                 while (head[0] != '\0') {
 349                         if (head[0] == '$') {
 350                                 /* substitute named variable */
 351                                 if (head[1] == '\0')
 352                                         break;
 353                                 if (head[1] == '$') {
 354                                         strlcpy(temp, head+2, sizeof(temp));
 355                                         strlcpy(head+1, temp, maxsize);
 356                                         head++;
 357                                         continue;
 358                                 }
 359                                 head[0] = '\0';
 360                                 for (subst = map; subst->name; subst++) {
 361                                         if (strncasecmp(&head[1], subst->name, strlen(subst->name)) == 0) {
 362                                                 type = subst->type;
 363                                                 tail = head + strlen(subst->name)+1;
 364                                                 dbg("will substitute format name '%s'", subst->name);
 365                                                 goto found;
 366                                         }
 367                                 }
 368                         } else if (head[0] == '%') {
 369                                 /* substitute format char */
 370                                 if (head[1] == '\0')
 371                                         break;
 372                                 if (head[1] == '%') {
 373                                         strlcpy(temp, head+2, sizeof(temp));
 374                                         strlcpy(head+1, temp, maxsize);
 375                                         head++;
 376                                         continue;
 377                                 }
 378                                 head[0] = '\0';
 379                                 tail = head+1;
 380                                 len = get_format_len(&tail);
 381                                 for (subst = map; subst->name; subst++) {
 382                                         if (tail[0] == subst->fmt) {
 383                                                 type = subst->type;
 384                                                 tail++;
 385                                                 dbg("will substitute format char '%c'", subst->fmt);
 386                                                 goto found;
 387                                         }
 388                                 }
 389                         }
 390                         head++;
 391                 }
 392                 break;
 393 found:
 394                 attr = get_format_attribute(&tail);
 395                 strlcpy(temp, tail, sizeof(temp));
 396                 dbg("format=%i, string='%s', tail='%s'", type ,string, tail);
 397
 398                 switch (type) {
 399                 case SUBST_DEVPATH:
 400                         strlcat(string, udev->dev->devpath, maxsize);
 401                         dbg("substitute devpath '%s'", udev->dev->devpath);
 402                         break;
 403                 case SUBST_KERNEL:
 404                         strlcat(string, udev->dev->kernel, maxsize);
 405                         dbg("substitute kernel name '%s'", udev->dev->kernel);
 406                         break;
 407                 case SUBST_KERNEL_NUMBER:
 408                         strlcat(string, udev->dev->kernel_number, maxsize);
 409                         dbg("substitute kernel number '%s'", udev->dev->kernel_number);
 410                         break;
 411                 case SUBST_ID:
 412                         if (udev->dev_parent != NULL) {
 413                                 strlcat(string, udev->dev_parent->kernel, maxsize);
 414                                 dbg("substitute id '%s'", udev->dev_parent->kernel);
 415                         }
 416                         break;
 417                 case SUBST_MAJOR:
 418                         sprintf(temp2, "%d", major(udev->devt));
 419                         strlcat(string, temp2, maxsize);
 420                         dbg("substitute major number '%s'", temp2);
 421                         break;
 422                 case SUBST_MINOR:
 423                         sprintf(temp2, "%d", minor(udev->devt));
 424                         strlcat(string, temp2, maxsize);
 425                         dbg("substitute minor number '%s'", temp2);
 426                         break;
 427                 case SUBST_RESULT:
 428                         if (udev->program_result[0] == '\0')
 429                                 break;
 430                         /* get part part of the result string */
 431                         i = 0;
 432                         if (attr != NULL)
 433                                 i = strtoul(attr, &rest, 10);
 434                         if (i > 0) {
 435                                 dbg("request part #%d of result string", i);
 436                                 cpos = udev->program_result;
 437                                 while (--i) {
 438                                         while (cpos[0] != '\0' && !isspace(cpos[0]))
 439                                                 cpos++;
 440                                         while (isspace(cpos[0]))
 441                                                 cpos++;
 442                                 }
 443                                 if (i > 0) {
 444                                         err("requested part of result string not found");
 445                                         break;
 446                                 }
 447                                 strlcpy(temp2, cpos, sizeof(temp2));
 448                                 /* %{2+}c copies the whole string from the second part on */
 449                                 if (rest[0] != '+') {
 450                                         cpos = strchr(temp2, ' ');
 451                                         if (cpos)
 452                                                 cpos[0] = '\0';
 453                                 }
 454                                 strlcat(string, temp2, maxsize);
 455                                 dbg("substitute part of result string '%s'", temp2);
 456                         } else {
 457                                 strlcat(string, udev->program_result, maxsize);
 458                                 dbg("substitute result string '%s'", udev->program_result);
 459                         }
 460                         break;
 461                 case SUBST_ATTR:
 462                         if (attr == NULL) {
 463                                 dbg("missing attribute");
 464                                 break;
 465                         } else {
 466                                 struct sysfs_device *dev_parent;
 467                                 const char *value;
 468
 469                                 dev_parent = udev->dev;
 470                                 do {
 471                                         dbg("looking at '%s'", dev_parent->devpath);
 472                                         value = sysfs_attr_get_value(dev_parent->devpath, attr);
 473                                         if (value != NULL) {
 474                                                 strlcpy(temp2, value, sizeof(temp2));
 475                                                 break;
 476                                         }
 477                                         dev_parent = sysfs_device_get_parent(dev_parent);
 478                                 } while (dev_parent != NULL);
 479
 480                                 /* strip trailing whitespace of sysfs value */
 481                                 i = strlen(temp2);
 482                                 while (i > 0 && isspace(temp2[i-1]))
 483                                         temp2[--i] = '\0';
 484                                 count = replace_untrusted_chars(temp2);
 485                                 if (count)
 486                                         info("%i untrusted character(s) replaced" , count);
 487                                 strlcat(string, temp2, maxsize);
 488                                 dbg("substitute sysfs value '%s'", temp2);
 489                         }
 490                         break;
 491                 case SUBST_PARENT:
 492                         {
 493                                 struct sysfs_device *dev_parent;
 494
 495                                 dev_parent = sysfs_device_get_parent(udev->dev);
 496                                 if (dev_parent != NULL) {
 497                                         struct udevice *udev_parent;
 498
 499                                         dbg("found parent '%s', get the node name", dev_parent->devpath);
 500                                         udev_parent = udev_device_init();
 501                                         if (udev_parent != NULL) {
 502                                                 /* lookup the name in the udev_db with the DEVPATH of the parent */
 503                                                 if (udev_db_get_device(udev_parent, dev_parent->devpath) == 0) {
 504                                                         strlcat(string, udev_parent->name, maxsize);
 505                                                         dbg("substitute parent node name'%s'", udev_parent->name);
 506                                                 } else
 507                                                         dbg("parent not found in database");
 508                                                 udev_device_cleanup(udev_parent);
 509                                         }
 510                                 }
 511                         }
 512                         break;
 513                 case SUBST_TEMP_NODE:
 514                         if (udev->tmp_node[0] == '\0') {
 515                                 dbg("create temporary device node for callout");
 516                                 snprintf(udev->tmp_node, sizeof(udev->tmp_node), "%s/.tmp-%u-%u",
 517                                          udev_root, major(udev->devt), minor(udev->devt));
 518                                 udev->tmp_node[sizeof(udev->tmp_node)-1] = '\0';
 519                                 udev_node_mknod(udev, udev->tmp_node, udev->devt, 0600, 0, 0);
 520                         }
 521                         strlcat(string, udev->tmp_node, maxsize);
 522                         dbg("substitute temporary device node name '%s'", udev->tmp_node);
 523                         break;
 524                 case SUBST_ROOT:
 525                         strlcat(string, udev_root, maxsize);
 526                         dbg("substitute udev_root '%s'", udev_root);
 527                         break;
 528                 case SUBST_ENV:
 529                         if (attr == NULL) {
 530                                 dbg("missing attribute");
 531                                 break;
 532                         }
 533                         pos = getenv(attr);
 534                         if (pos == NULL) {
 535                                 dbg("env '%s' not available", attr);
 536                                 break;
 537                         }
 538                         dbg("substitute env '%s=%s'", attr, pos);
 539                         strlcat(string, pos, maxsize);
 540                         break;
 541                 default:
 542                         err("unknown substitution type=%i", type);
 543                         break;
 544                 }
 545                 /* possibly truncate to format-char specified length */
 546                 if (len != -1) {
 547                         head[len] = '\0';
 548                         dbg("truncate to %i chars, subtitution string becomes '%s'", len, head);
 549                 }
 550                 strlcat(string, temp, maxsize);
 551         }
 552 }
 553
 554 static char *key_val(struct udev_rule *rule, struct key *key)
 555 {
 556         return rule->buf + key->val_off;
 557 }
 558
 559 static char *key_pair_name(struct udev_rule *rule, struct key_pair *pair)
 560 {
 561         return rule->buf + pair->key_name_off;
 562 }
 563
 564 static int match_key(const char *key_name, struct udev_rule *rule, struct key *key, const char *val)
 565 {
 566         int match;
 567         char value[PATH_SIZE];
 568         char *key_value;
 569         char *pos;
 570
 571         if (key->operation != KEY_OP_MATCH &&
 572             key->operation != KEY_OP_NOMATCH)
 573                 return 0;
 574
 575         strlcpy(value, rule->buf + key->val_off, sizeof(value));
 576         key_value = value;
 577
 578         dbg("key %s value='%s'", key_name, key_value);
 579         while (key_value) {
 580                 pos = strchr(key_value, '|');
 581                 if (pos) {
 582                         pos[0] = '\0';
 583                         pos++;
 584                 }
 585                 dbg("match %s '%s' <-> '%s'", key_name, key_value, val);
 586                 match = (strcmp_pattern(key_value, val) == 0);
 587                 if (match && (key->operation != KEY_OP_NOMATCH)) {
 588                         dbg("%s is true (matching value)", key_name);
 589                         return 0;
 590                 }
 591                 if (!match && (key->operation == KEY_OP_NOMATCH)) {
 592                         dbg("%s is true (non-matching value)", key_name);
 593                         return 0;
 594                 }
 595                 key_value = pos;
 596         }
 597         dbg("%s is false", key_name);
 598         return -1;
 599 }
 600
 601 /* match a single rule against a given device and possibly its parent devices */
 602 static int match_rule(struct udevice *udev, struct udev_rule *rule)
 603 {
 604         int i;
 605
 606         if (match_key("ACTION", rule, &rule->action, udev->action))
 607                 goto nomatch;
 608
 609         if (match_key("KERNEL", rule, &rule->kernel, udev->dev->kernel))
 610                 goto nomatch;
 611
 612         if (match_key("SUBSYSTEM", rule, &rule->subsystem, udev->dev->subsystem))
 613                 goto nomatch;
 614
 615         if (match_key("DEVPATH", rule, &rule->devpath, udev->dev->devpath))
 616                 goto nomatch;
 617
 618         if (match_key("DRIVER", rule, &rule->driver, udev->dev->driver))
 619                 goto nomatch;
 620
 621         /* match NAME against a value assigned by an earlier rule */
 622         if (match_key("NAME", rule, &rule->name, udev->name))
 623                 goto nomatch;
 624
 625         for (i = 0; i < rule->env.count; i++) {
 626                 struct key_pair *pair = &rule->env.keys[i];
 627
 628                 /* we only check for matches, assignments will be handled later */
 629                 if (pair->key.operation == KEY_OP_MATCH ||
 630                     pair->key.operation == KEY_OP_NOMATCH) {
 631                         const char *key_name = key_pair_name(rule, pair);
 632                         const char *value = getenv(key_name);
 633
 634                         if (!value) {
 635                                 dbg("ENV{'%s'} is not set, treat as empty", key_name);
 636                                 value = "";
 637                         }
 638                         if (match_key("ENV", rule, &pair->key, value))
 639                                 goto nomatch;
 640                 }
 641         }
 642
 643         if (rule->wait_for_sysfs.operation != KEY_OP_UNSET) {
 644                 int found;
 645
 646                 found = (wait_for_sysfs(udev, key_val(rule, &rule->wait_for_sysfs), 3) == 0);
 647                 if (!found && (rule->wait_for_sysfs.operation != KEY_OP_NOMATCH))
 648                         goto nomatch;
 649         }
 650
 651         /* check for matching sysfs attribute pairs */
 652         for (i = 0; i < rule->attr.count; i++) {
 653                 struct key_pair *pair = &rule->attr.keys[i];
 654
 655                 if (pair->key.operation == KEY_OP_MATCH ||
 656                     pair->key.operation == KEY_OP_NOMATCH) {
 657                         const char *key_name = key_pair_name(rule, pair);
 658                         const char *key_value = key_val(rule, &pair->key);
 659                         const char *value;
 660                         char val[VALUE_SIZE];
 661                         size_t len;
 662
 663                         value = sysfs_attr_get_value(udev->dev->devpath, key_name);
 664                         if (value == NULL)
 665                                 goto nomatch;
 666                         strlcpy(val, value, sizeof(val));
 667
 668                         /* strip trailing whitespace of value, if not asked to match for it */
 669                         len = strlen(key_value);
 670                         if (len > 0 && !isspace(key_value[len-1])) {
 671                                 len = strlen(val);
 672                                 while (len > 0 && isspace(val[len-1]))
 673                                         val[--len] = '\0';
 674                                 dbg("removed %zi trailing whitespace chars from '%s'", strlen(val)-len, val);
 675                         }
 676
 677                         if (match_key("ATTR", rule, &pair->key, val))
 678                                 goto nomatch;
 679                 }
 680         }
 681
 682         /* walk up the chain of parent devices and find a match */
 683         udev->dev_parent = udev->dev;
 684         while (1) {
 685                 /* check for matching kernel device name */
 686                 if (match_key("KERNELS", rule, &rule->kernels, udev->dev_parent->kernel))
 687                         goto try_parent;
 688
 689                 /* check for matching subsystem value */
 690                 if (match_key("SUBSYSTEMS", rule, &rule->subsystems, udev->dev_parent->subsystem))
 691                         goto try_parent;
 692
 693                 /* check for matching driver */
 694                 if (match_key("DRIVERS", rule, &rule->drivers, udev->dev_parent->driver))
 695                         goto try_parent;
 696
 697                 /* check for matching sysfs attrubute pairs */
 698                 for (i = 0; i < rule->attrs.count; i++) {
 699                         struct key_pair *pair = &rule->attrs.keys[i];
 700
 701                         if (pair->key.operation == KEY_OP_MATCH ||
 702                             pair->key.operation == KEY_OP_NOMATCH) {
 703                                 const char *key_name = key_pair_name(rule, pair);
 704                                 const char *key_value = key_val(rule, &pair->key);
 705                                 const char *value;
 706                                 char val[VALUE_SIZE];
 707                                 size_t len;
 708
 709                                 value = sysfs_attr_get_value(udev->dev_parent->devpath, key_name);
 710                                 if (value == NULL)
 711                                         value = sysfs_attr_get_value(udev->dev->devpath, key_name);
 712                                 if (value == NULL)
 713                                         goto try_parent;
 714                                 strlcpy(val, value, sizeof(val));
 715
 716                                 /* strip trailing whitespace of value, if not asked to match for it */
 717                                 len = strlen(key_value);
 718                                 if (len > 0 && !isspace(key_value[len-1])) {
 719                                         len = strlen(val);
 720                                         while (len > 0 && isspace(val[len-1]))
 721                                                 val[--len] = '\0';
 722                                         dbg("removed %zi trailing whitespace chars from '%s'", strlen(val)-len, val);
 723                                 }
 724
 725                                 if (match_key("ATTRS", rule, &pair->key, val))
 726                                         goto try_parent;
 727                         }
 728                 }
 729
 730                 /* found matching device  */
 731                 break;
 732 try_parent:
 733                 /* move to parent device */
 734                 dbg("try parent sysfs device");
 735                 udev->dev_parent = sysfs_device_get_parent(udev->dev_parent);
 736                 if (udev->dev_parent == NULL)
 737                         goto nomatch;
 738                 dbg("looking at dev_parent->devpath='%s'", udev->dev_parent->devpath);
 739                 dbg("looking at dev_parent->kernel='%s'", udev->dev_parent->kernel);
 740         }
 741
 742         /* execute external program */
 743         if (rule->program.operation != KEY_OP_UNSET) {
 744                 char program[PATH_SIZE];
 745                 char result[PATH_SIZE];
 746
 747                 strlcpy(program, key_val(rule, &rule->program), sizeof(program));
 748                 udev_rules_apply_format(udev, program, sizeof(program));
 749                 if (run_program(program, udev->dev->subsystem, result, sizeof(result), NULL, (udev_log_priority >= LOG_INFO)) != 0) {
 750                         dbg("PROGRAM is false");
 751                         udev->program_result[0] = '\0';
 752                         if (rule->program.operation != KEY_OP_NOMATCH)
 753                                 goto nomatch;
 754                 } else {
 755                         int count;
 756
 757                         dbg("PROGRAM matches");
 758                         remove_trailing_chars(result, '\n');
 759                         count = replace_untrusted_chars(result);
 760                         if (count)
 761                                 info("%i untrusted character(s) replaced" , count);
 762                         dbg("result is '%s'", result);
 763                         strlcpy(udev->program_result, result, sizeof(udev->program_result));
 764                         dbg("PROGRAM returned successful");
 765                         if (rule->program.operation == KEY_OP_NOMATCH)
 766                                 goto nomatch;
 767                 }
 768                 dbg("PROGRAM key is true");
 769         }
 770
 771         /* check for matching result of external program */
 772         if (match_key("RESULT", rule, &rule->result, udev->program_result))
 773                 goto nomatch;
 774
 775         /* import variables returned from program or or file into environment */
 776         if (rule->import.operation != KEY_OP_UNSET) {
 777                 char import[PATH_SIZE];
 778                 int rc = -1;
 779
 780                 strlcpy(import, key_val(rule, &rule->import), sizeof(import));
 781                 udev_rules_apply_format(udev, import, sizeof(import));
 782                 dbg("check for IMPORT import='%s'", import);
 783                 if (rule->import_type == IMPORT_PROGRAM) {
 784                         rc = import_program_into_env(udev, import);
 785                 } else if (rule->import_type == IMPORT_FILE) {
 786                         dbg("import file import='%s'", import);
 787                         rc = import_file_into_env(udev, import);
 788                 } else if (rule->import_type == IMPORT_PARENT) {
 789                         dbg("import parent import='%s'", import);
 790                         rc = import_parent_into_env(udev, import);
 791                 }
 792                 if (rc != 0) {
 793                         dbg("IMPORT failed");
 794                         if (rule->import.operation != KEY_OP_NOMATCH)
 795                                 goto nomatch;
 796                 } else
 797                         dbg("IMPORT '%s' imported", key_val(rule, &rule->import));
 798                 dbg("IMPORT key is true");
 799         }
 800
 801         /* rule matches, if we have ENV assignments export it */
 802         for (i = 0; i < rule->env.count; i++) {
 803                 struct key_pair *pair = &rule->env.keys[i];
 804
 805                 if (pair->key.operation == KEY_OP_ASSIGN) {
 806                         const char *key_name = key_pair_name(rule, pair);
 807                         const char *value = key_val(rule, &pair->key);
 808                         char *key_value = name_list_key_add(&udev->env_list, key_name, value);
 809                         if (key_value == NULL)
 810                                 break;
 811
 812                         udev_rules_apply_format(udev, key_value, NAME_SIZE);
 813                         putenv(key_value);
 814                         dbg("export ENV '%s'", key_value);
 815                 }
 816         }
 817
 818         /* if we have ATTR assignements write value to sysfs file */
 819         for (i = 0; i < rule->attr.count; i++) {
 820                 struct key_pair *pair = &rule->attr.keys[i];
 821
 822                 if (pair->key.operation == KEY_OP_ASSIGN) {
 823                         const char *key_name = key_pair_name(rule, pair);
 824                         const char *key_value = key_val(rule, &pair->key);
 825                         char attr[PATH_SIZE];
 826                         FILE *f;
 827
 828                         strlcpy(attr, sysfs_path, sizeof(attr));
 829                         strlcat(attr, udev->dev->devpath, sizeof(attr));
 830                         strlcat(attr, "/", sizeof(attr));
 831                         strlcat(attr, key_name, sizeof(attr));
 832                         dbg("write '%s' to '%s'", key_value, attr);
 833                         f = fopen(attr, "w");
 834                         if (f != NULL) {
 835                                 if (fprintf(f, "%s\n", key_value) <= 0)
 836                                         err("error writing ATTR{%s}: %s", attr, strerror(errno));
 837                                 fclose(f);
 838                         } else
 839                                 err("error opening ATTR{%s} for writing: %s", attr, strerror(errno));
 840                 }
 841         }
 842         return 0;
 843
 844 nomatch:
 845         return -1;
 846 }
 847
 848 int udev_rules_get_name(struct udev_rules *rules, struct udevice *udev)
 849 {
 850         struct udev_rule *rule;
 851         int name_set = 0;
 852
 853         dbg("udev->dev->devpath='%s'", udev->dev->devpath);
 854         dbg("udev->dev->kernel='%s'", udev->dev->kernel);
 855
 856         /* look for a matching rule to apply */
 857         udev_rules_iter_init(rules);
 858         while (1) {
 859                 rule = udev_rules_iter_next(rules);
 860                 if (rule == NULL)
 861                         break;
 862
 863                 if (name_set &&
 864                     (rule->name.operation == KEY_OP_ASSIGN ||
 865                      rule->name.operation == KEY_OP_ASSIGN_FINAL ||
 866                      rule->name.operation == KEY_OP_ADD)) {
 867                         dbg("node name already set, rule ignored");
 868                         continue;
 869                 }
 870
 871                 dbg("process rule");
 872                 if (match_rule(udev, rule) == 0) {
 873                         /* apply options */
 874                         if (rule->ignore_device) {
 875                                 info("rule applied, '%s' is ignored", udev->dev->kernel);
 876                                 udev->ignore_device = 1;
 877                                 return 0;
 878                         }
 879                         if (rule->ignore_remove) {
 880                                 udev->ignore_remove = 1;
 881                                 dbg("remove event should be ignored");
 882                         }
 883                         /* apply all_partitions option only at a main block device */
 884                         if (rule->partitions &&
 885                             strcmp(udev->dev->subsystem, "block") == 0 && udev->dev->kernel_number[0] == '\0') {
 886                                 udev->partitions = rule->partitions;
 887                                 dbg("creation of partition nodes requested");
 888                         }
 889
 890                         /* apply permissions */
 891                         if (!udev->mode_final && rule->mode != 0000) {
 892                                 if (rule->mode_operation == KEY_OP_ASSIGN_FINAL)
 893                                         udev->mode_final = 1;
 894                                 udev->mode = rule->mode;
 895                                 dbg("applied mode=%#o to '%s'", rule->mode, udev->dev->kernel);
 896                         }
 897                         if (!udev->owner_final && rule->owner.operation != KEY_OP_UNSET) {
 898                                 if (rule->owner.operation == KEY_OP_ASSIGN_FINAL)
 899                                         udev->owner_final = 1;
 900                                 strlcpy(udev->owner, key_val(rule, &rule->owner), sizeof(udev->owner));
 901                                 udev_rules_apply_format(udev, udev->owner, sizeof(udev->owner));
 902                                 dbg("applied owner='%s' to '%s'", udev->owner, udev->dev->kernel);
 903                         }
 904                         if (!udev->group_final && rule->group.operation != KEY_OP_UNSET) {
 905                                 if (rule->group.operation == KEY_OP_ASSIGN_FINAL)
 906                                         udev->group_final = 1;
 907                                 strlcpy(udev->group, key_val(rule, &rule->group), sizeof(udev->group));
 908                                 udev_rules_apply_format(udev, udev->group, sizeof(udev->group));
 909                                 dbg("applied group='%s' to '%s'", udev->group, udev->dev->kernel);
 910                         }
 911
 912                         /* collect symlinks */
 913                         if (!udev->symlink_final && rule->symlink.operation != KEY_OP_UNSET) {
 914                                 char temp[PATH_SIZE];
 915                                 char *pos, *next;
 916                                 int count;
 917
 918                                 if (rule->symlink.operation == KEY_OP_ASSIGN_FINAL)
 919                                         udev->symlink_final = 1;
 920                                 if (rule->symlink.operation == KEY_OP_ASSIGN || rule->symlink.operation == KEY_OP_ASSIGN_FINAL) {
 921                                         info("reset symlink list");
 922                                         name_list_cleanup(&udev->symlink_list);
 923                                 }
 924                                 strlcpy(temp, key_val(rule, &rule->symlink), sizeof(temp));
 925                                 udev_rules_apply_format(udev, temp, sizeof(temp));
 926                                 count = replace_untrusted_chars(temp);
 927                                 if (count)
 928                                         info("%i untrusted character(s) replaced" , count);
 929                                 dbg("rule applied, added symlink(s) '%s'", temp);
 930
 931                                 /* add multiple symlinks separated by spaces */
 932                                 pos = temp;
 933                                 while (isspace(pos[0]))
 934                                         pos++;
 935                                 next = strchr(pos, ' ');
 936                                 while (next) {
 937                                         next[0] = '\0';
 938                                         info("add symlink '%s'", pos);
 939                                         name_list_add(&udev->symlink_list, pos, 0);
 940                                         while (isspace(next[1]))
 941                                                 next++;
 942                                         pos = &next[1];
 943                                         next = strchr(pos, ' ');
 944                                 }
 945                                 if (pos[0] != '\0') {
 946                                         info("add symlink '%s'", pos);
 947                                         name_list_add(&udev->symlink_list, pos, 0);
 948                                 }
 949                         }
 950
 951                         /* set name, later rules with name set will be ignored */
 952                         if (rule->name.operation == KEY_OP_ASSIGN ||
 953                             rule->name.operation == KEY_OP_ASSIGN_FINAL ||
 954                             rule->name.operation == KEY_OP_ADD) {
 955                                 int count;
 956
 957                                 name_set = 1;
 958                                 strlcpy(udev->name, key_val(rule, &rule->name), sizeof(udev->name));
 959                                 udev_rules_apply_format(udev, udev->name, sizeof(udev->name));
 960                                 count = replace_untrusted_chars(udev->name);
 961                                 if (count)
 962                                         info("%i untrusted character(s) replaced", count);
 963
 964                                 info("rule applied, '%s' becomes '%s'", udev->dev->kernel, udev->name);
 965                                 if (strcmp(udev->dev->subsystem, "net") != 0)
 966                                         dbg("name, '%s' is going to have owner='%s', group='%s', mode=%#o partitions=%i",
 967                                             udev->name, udev->owner, udev->group, udev->mode, udev->partitions);
 968                         }
 969
 970                         if (!udev->run_final && rule->run.operation != KEY_OP_UNSET) {
 971                                 if (rule->run.operation == KEY_OP_ASSIGN_FINAL)
 972                                         udev->run_final = 1;
 973                                 if (rule->run.operation == KEY_OP_ASSIGN || rule->run.operation == KEY_OP_ASSIGN_FINAL) {
 974                                         info("reset run list");
 975                                         name_list_cleanup(&udev->run_list);
 976                                 }
 977                                 dbg("add run '%s'", key_val(rule, &rule->run));
 978                                 name_list_add(&udev->run_list, key_val(rule, &rule->run), 0);
 979                         }
 980
 981                         if (rule->last_rule) {
 982                                 dbg("last rule to be applied");
 983                                 break;
 984                         }
 985
 986                         if (rule->goto_label.operation != KEY_OP_UNSET) {
 987                                 dbg("moving forward to label '%s'", key_val(rule, &rule->goto_label));
 988                                 udev_rules_iter_label(rules, key_val(rule, &rule->goto_label));
 989                         }
 990                 }
 991         }
 992
 993         if (!name_set) {
 994                 strlcpy(udev->name, udev->dev->kernel, sizeof(udev->name));
 995                 info("no node name set, will use kernel name '%s'", udev->name);
 996         }
 997
 998         if (udev->tmp_node[0] != '\0') {
 999                 dbg("removing temporary device node");
1000                 unlink_secure(udev->tmp_node);
1001                 udev->tmp_node[0] = '\0';
1002         }
1003
1004         return 0;
1005 }
1006
1007 int udev_rules_get_run(struct udev_rules *rules, struct udevice *udev)
1008 {
1009         struct udev_rule *rule;
1010
1011         dbg("udev->kernel='%s'", udev->dev->kernel);
1012
1013         /* look for a matching rule to apply */
1014         udev_rules_iter_init(rules);
1015         while (1) {
1016                 rule = udev_rules_iter_next(rules);
1017                 if (rule == NULL)
1018                         break;
1019
1020                 dbg("process rule");
1021                 if (rule->name.operation != KEY_OP_UNSET || rule->symlink.operation != KEY_OP_UNSET ||
1022                     rule->mode_operation != KEY_OP_UNSET || rule->owner.operation != KEY_OP_UNSET || rule->group.operation != KEY_OP_UNSET) {
1023                         dbg("skip rule that names a device");
1024                         continue;
1025                 }
1026
1027                 if (match_rule(udev, rule) == 0) {
1028                         if (rule->ignore_device) {
1029                                 info("rule applied, '%s' is ignored", udev->dev->kernel);
1030                                 udev->ignore_device = 1;
1031                                 return 0;
1032                         }
1033
1034                         if (!udev->run_final && rule->run.operation != KEY_OP_UNSET) {
1035                                 if (rule->run.operation == KEY_OP_ASSIGN || rule->run.operation == KEY_OP_ASSIGN_FINAL) {
1036                                         info("reset run list");
1037                                         name_list_cleanup(&udev->run_list);
1038                                 }
1039                                 dbg("add run '%s'", key_val(rule, &rule->run));
1040                                 name_list_add(&udev->run_list, key_val(rule, &rule->run), 0);
1041                                 if (rule->run.operation == KEY_OP_ASSIGN_FINAL)
1042                                         break;
1043                         }
1044
1045                         if (rule->last_rule) {
1046                                 dbg("last rule to be applied");
1047                                 break;
1048                         }
1049
1050                         if (rule->goto_label.operation != KEY_OP_UNSET) {
1051                                 dbg("moving forward to label '%s'", key_val(rule, &rule->goto_label));
1052                                 udev_rules_iter_label(rules, key_val(rule, &rule->goto_label));
1053                         }
1054                 }
1055         }
1056
1057         return 0;
1058 }