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 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 unlikely 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                         } else if (head[0] == '%') {
 455                                 /* substitute format char */
 456                                 if (head[1] == '\0')
 457                                         break;
 458                                 if (head[1] == '%') {
 459                                         strlcpy(temp, head+2, sizeof(temp));
 460                                         strlcpy(head+1, temp, maxsize);
 461                                         head++;
 462                                         continue;
 463                                 }
 464                                 head[0] = '\0';
 465                                 tail = head+1;
 466                                 len = get_format_len(&tail);
 467                                 for (subst = map; subst->name; subst++) {
 468                                         if (tail[0] == subst->fmt) {
 469                                                 type = subst->type;
 470                                                 tail++;
 471                                                 dbg("will substitute format char '%c'", subst->fmt);
 472                                                 goto found;
 473                                         }
 474                                 }
 475                         }
 476                         head++;
 477                 }
 478                 break;
 479 found:
 480                 attr = get_format_attribute(&tail);
 481                 strlcpy(temp, tail, sizeof(temp));
 482                 dbg("format=%i, string='%s', tail='%s'", type ,string, tail);
 483
 484                 switch (type) {
 485                 case SUBST_DEVPATH:
 486                         strlcat(string, udev->dev->devpath, maxsize);
 487                         dbg("substitute devpath '%s'", udev->dev->devpath);
 488                         break;
 489                 case SUBST_KERNEL_NAME:
 490                         strlcat(string, udev->dev->kernel_name, maxsize);
 491                         dbg("substitute kernel name '%s'", udev->dev->kernel_name);
 492                         break;
 493                 case SUBST_KERNEL_NUMBER:
 494                         strlcat(string, udev->dev->kernel_number, maxsize);
 495                         dbg("substitute kernel number '%s'", udev->dev->kernel_number);
 496                         break;
 497                 case SUBST_ID:
 498                         if (udev->dev_parent != NULL) {
 499                                 strlcat(string, udev->dev_parent->kernel_name, maxsize);
 500                                 dbg("substitute id '%s'", udev->dev_parent->kernel_name);
 501                         }
 502                         break;
 503                 case SUBST_MAJOR:
 504                         sprintf(temp2, "%d", major(udev->devt));
 505                         strlcat(string, temp2, maxsize);
 506                         dbg("substitute major number '%s'", temp2);
 507                         break;
 508                 case SUBST_MINOR:
 509                         sprintf(temp2, "%d", minor(udev->devt));
 510                         strlcat(string, temp2, maxsize);
 511                         dbg("substitute minor number '%s'", temp2);
 512                         break;
 513                 case SUBST_RESULT:
 514                         if (udev->program_result[0] == '\0')
 515                                 break;
 516                         /* get part part of the result string */
 517                         i = 0;
 518                         if (attr != NULL)
 519                                 i = strtoul(attr, &rest, 10);
 520                         if (i > 0) {
 521                                 dbg("request part #%d of result string", i);
 522                                 cpos = udev->program_result;
 523                                 while (--i) {
 524                                         while (cpos[0] != '\0' && !isspace(cpos[0]))
 525                                                 cpos++;
 526                                         while (isspace(cpos[0]))
 527                                                 cpos++;
 528                                 }
 529                                 if (i > 0) {
 530                                         err("requested part of result string not found");
 531                                         break;
 532                                 }
 533                                 strlcpy(temp2, cpos, sizeof(temp2));
 534                                 /* %{2+}c copies the whole string from the second part on */
 535                                 if (rest[0] != '+') {
 536                                         cpos = strchr(temp2, ' ');
 537                                         if (cpos)
 538                                                 cpos[0] = '\0';
 539                                 }
 540                                 strlcat(string, temp2, maxsize);
 541                                 dbg("substitute part of result string '%s'", temp2);
 542                         } else {
 543                                 strlcat(string, udev->program_result, maxsize);
 544                                 dbg("substitute result string '%s'", udev->program_result);
 545                         }
 546                         break;
 547                 case SUBST_SYSFS:
 548                         if (attr == NULL) {
 549                                 dbg("missing attribute");
 550                                 break;
 551                         } else {
 552                                 struct sysfs_device *dev_parent;
 553                                 const char *value;
 554
 555                                 dev_parent = udev->dev;
 556                                 do {
 557                                         dbg("looking at '%s'", dev_parent->devpath);
 558                                         value = sysfs_attr_get_value(dev_parent->devpath, attr);
 559                                         if (value != NULL) {
 560                                                 strlcpy(temp2, value, sizeof(temp2));
 561                                                 break;
 562                                         }
 563                                         dev_parent = sysfs_device_get_parent(dev_parent);
 564                                 } while (dev_parent != NULL);
 565
 566                                 /* strip trailing whitespace of sysfs value */
 567                                 i = strlen(temp2);
 568                                 while (i > 0 && isspace(temp2[i-1]))
 569                                         temp2[--i] = '\0';
 570                                 count = replace_untrusted_chars(temp2);
 571                                 if (count)
 572                                         info("%i untrusted character(s) replaced" , count);
 573                                 strlcat(string, temp2, maxsize);
 574                                 dbg("substitute sysfs value '%s'", temp2);
 575                         }
 576                         break;
 577                 case SUBST_ENUM:
 578                         next_free_number = find_free_number(string, udev->dev->devpath);
 579                         if (next_free_number > 0) {
 580                                 sprintf(temp2, "%d", next_free_number);
 581                                 strlcat(string, temp2, maxsize);
 582                         }
 583                         break;
 584                 case SUBST_PARENT:
 585                         {
 586                                 struct sysfs_device *dev_parent;
 587
 588                                 dev_parent = sysfs_device_get_parent(udev->dev);
 589                                 if (dev_parent != NULL) {
 590                                         struct udevice *udev_parent;
 591
 592                                         dbg("found parent '%s', get the node name", dev_parent->devpath);
 593                                         udev_parent = udev_device_init();
 594                                         if (udev_parent != NULL) {
 595                                                 /* lookup the name in the udev_db with the DEVPATH of the parent */
 596                                                 if (udev_db_get_device(udev_parent, dev_parent->devpath) == 0) {
 597                                                         strlcat(string, udev_parent->name, maxsize);
 598                                                         dbg("substitute parent node name'%s'", udev_parent->name);
 599                                                 } else
 600                                                         dbg("parent not found in database");
 601                                                 udev_device_cleanup(udev_parent);
 602                                         }
 603                                 }
 604                         }
 605                         break;
 606                 case SUBST_TEMP_NODE:
 607                         if (udev->tmp_node[0] == '\0') {
 608                                 dbg("create temporary device node for callout");
 609                                 snprintf(udev->tmp_node, sizeof(udev->tmp_node), "%s/.tmp-%u-%u",
 610                                          udev_root, major(udev->devt), minor(udev->devt));
 611                                 udev->tmp_node[sizeof(udev->tmp_node)-1] = '\0';
 612                                 udev_node_mknod(udev, udev->tmp_node, udev->devt, 0600, 0, 0);
 613                         }
 614                         strlcat(string, udev->tmp_node, maxsize);
 615                         dbg("substitute temporary device node name '%s'", udev->tmp_node);
 616                         break;
 617                 case SUBST_ROOT:
 618                         strlcat(string, udev_root, maxsize);
 619                         dbg("substitute udev_root '%s'", udev_root);
 620                         break;
 621                 case SUBST_MODALIAS:
 622                         {
 623                                 const char *value;
 624                                 static int warn = 1;
 625
 626                                 if (warn) {
 627                                         err("$modalias is deprecated, use $env{MODALIAS} or "
 628                                             "$sysfs{modalias} instead.");
 629                                         warn = 0;
 630                                 }
 631
 632                                 value = sysfs_attr_get_value(udev->dev->devpath, "modalias");
 633                                 if (value != NULL) {
 634                                         strlcat(string, value, maxsize);
 635                                         dbg("substitute MODALIAS '%s'", temp2);
 636                                 }
 637                         }
 638                         break;
 639                 case SUBST_ENV:
 640                         if (attr == NULL) {
 641                                 dbg("missing attribute");
 642                                 break;
 643                         }
 644                         pos = getenv(attr);
 645                         if (pos == NULL) {
 646                                 dbg("env '%s' not available", attr);
 647                                 break;
 648                         }
 649                         dbg("substitute env '%s=%s'", attr, pos);
 650                         strlcat(string, pos, maxsize);
 651                         break;
 652                 default:
 653                         err("unknown substitution type=%i", type);
 654                         break;
 655                 }
 656                 /* possibly truncate to format-char specified length */
 657                 if (len != -1) {
 658                         head[len] = '\0';
 659                         dbg("truncate to %i chars, subtitution string becomes '%s'", len, head);
 660                 }
 661                 strlcat(string, temp, maxsize);
 662         }
 663 }
 664
 665 static char *key_val(struct udev_rule *rule, struct key *key)
 666 {
 667         return rule->buf + key->val_off;
 668 }
 669
 670 static char *key_pair_name(struct udev_rule *rule, struct key_pair *pair)
 671 {
 672         return rule->buf + pair->key_name_off;
 673 }
 674
 675 static int match_key(const char *key_name, struct udev_rule *rule, struct key *key, const char *val)
 676 {
 677         int match;
 678         char value[PATH_SIZE];
 679         char *key_value;
 680         char *pos;
 681
 682         if (key->operation != KEY_OP_MATCH &&
 683             key->operation != KEY_OP_NOMATCH)
 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         /* compare NAME against a previously assigned value */
 730         if (match_key("NAME", rule, &rule->name, udev->name))
 731                 goto nomatch;
 732
 733         if (rule->modalias.operation != KEY_OP_UNSET) {
 734                 const char *value;
 735                 static int warn = 1;
 736
 737                 if (warn) {
 738                         err("MODALIAS is deprecated, use ENV{MODALIAS} or SYSFS{modalias} instead.");
 739                         warn = 0;
 740                 }
 741
 742                 value = sysfs_attr_get_value(udev->dev->devpath, "modalias");
 743                 if (value == NULL) {
 744                         dbg("MODALIAS value not found");
 745                         goto nomatch;
 746                 }
 747                 if (match_key("MODALIAS", rule, &rule->modalias, value))
 748                         goto nomatch;
 749         }
 750
 751         for (i = 0; i < rule->env.count; i++) {
 752                 struct key_pair *pair = &rule->env.keys[i];
 753
 754                 /* we only check for matches, assignments will be handled later */
 755                 if (pair->key.operation == KEY_OP_MATCH ||
 756                     pair->key.operation == KEY_OP_NOMATCH) {
 757                         const char *key_name = key_pair_name(rule, pair);
 758                         const char *value = getenv(key_name);
 759
 760                         if (!value) {
 761                                 dbg("ENV{'%s'} is not set, treat as empty", key_name);
 762                                 value = "";
 763                         }
 764                         if (match_key("ENV", rule, &pair->key, value))
 765                                 goto nomatch;
 766                 }
 767         }
 768
 769         if (rule->wait_for_sysfs.operation != KEY_OP_UNSET) {
 770                 int found;
 771
 772                 found = (wait_for_sysfs(udev, key_val(rule, &rule->wait_for_sysfs), 3) == 0);
 773                 if (!found && (rule->wait_for_sysfs.operation != KEY_OP_NOMATCH)) {
 774                         dbg("WAIT_FOR_SYSFS failed");
 775                         goto nomatch;
 776                 }
 777         }
 778
 779         /* walk up the chain of parent devices and find a match */
 780         udev->dev_parent = udev->dev;
 781         while (1) {
 782                 /* check for matching driver */
 783                 if (match_key("DRIVER", rule, &rule->driver, udev->dev_parent->driver))
 784                         goto try_parent;
 785
 786                 /* check for matching subsystem/bus value */
 787                 if (match_key("BUS", rule, &rule->bus, udev->dev_parent->subsystem))
 788                         goto try_parent;
 789
 790                 /* check for matching bus id (device name) */
 791                 if (match_key("ID", rule, &rule->id, udev->dev_parent->kernel_name))
 792                         goto try_parent;
 793
 794                 /* check for matching sysfs pairs */
 795                 if (rule->sysfs.count) {
 796                         dbg("check %i SYSFS keys", rule->sysfs.count);
 797                         for (i = 0; i < rule->sysfs.count; i++) {
 798                                 struct key_pair *pair = &rule->sysfs.keys[i];
 799                                 const char *key_name = key_pair_name(rule, pair);
 800                                 const char *key_value = key_val(rule, &pair->key);
 801                                 const char *value;
 802                                 char val[VALUE_SIZE];
 803                                 size_t len;
 804
 805                                 value = sysfs_attr_get_value(udev->dev_parent->devpath, key_name);
 806                                 if (value == NULL)
 807                                         value = sysfs_attr_get_value(udev->dev->devpath, key_name);
 808                                 if (value == NULL)
 809                                         goto try_parent;
 810                                 strlcpy(val, value, sizeof(val));
 811
 812                                 /* strip trailing whitespace of value, if not asked to match for it */
 813                                 len = strlen(key_value);
 814                                 if (len > 0 && !isspace(key_value[len-1])) {
 815                                         len = strlen(val);
 816                                         while (len > 0 && isspace(val[len-1]))
 817                                                 val[--len] = '\0';
 818                                         dbg("removed %zi trailing whitespace chars from '%s'", strlen(val)-len, val);
 819                                 }
 820
 821                                 if (match_key("SYSFS", rule, &pair->key, val))
 822                                         goto try_parent;
 823                         }
 824                         dbg("all %i SYSFS keys matched", rule->sysfs.count);
 825                 }
 826
 827                 /* found matching device  */
 828                 break;
 829 try_parent:
 830                 /* move to parent device */
 831                 dbg("try parent sysfs device");
 832                 udev->dev_parent = sysfs_device_get_parent(udev->dev_parent);
 833                 if (udev->dev_parent == NULL)
 834                         goto nomatch;
 835                 dbg("looking at dev_parent->devpath='%s'", udev->dev_parent->devpath);
 836                 dbg("looking at dev_parent->bus_kernel_name='%s'", udev->dev_parent->kernel_name);
 837         }
 838
 839         /* execute external program */
 840         if (rule->program.operation != KEY_OP_UNSET) {
 841                 char program[PATH_SIZE];
 842                 char result[PATH_SIZE];
 843
 844                 strlcpy(program, key_val(rule, &rule->program), sizeof(program));
 845                 udev_rules_apply_format(udev, program, sizeof(program));
 846                 if (run_program(program, udev->dev->subsystem, result, sizeof(result), NULL, (udev_log_priority >= LOG_INFO)) != 0) {
 847                         dbg("PROGRAM is false");
 848                         udev->program_result[0] = '\0';
 849                         if (rule->program.operation != KEY_OP_NOMATCH)
 850                                 goto nomatch;
 851                 } else {
 852                         int count;
 853
 854                         dbg("PROGRAM matches");
 855                         remove_trailing_chars(result, '\n');
 856                         count = replace_untrusted_chars(result);
 857                         if (count)
 858                                 info("%i untrusted character(s) replaced" , count);
 859                         dbg("result is '%s'", result);
 860                         strlcpy(udev->program_result, result, sizeof(udev->program_result));
 861                         dbg("PROGRAM returned successful");
 862                         if (rule->program.operation == KEY_OP_NOMATCH)
 863                                 goto nomatch;
 864                 }
 865                 dbg("PROGRAM key is true");
 866         }
 867
 868         /* check for matching result of external program */
 869         if (match_key("RESULT", rule, &rule->result, udev->program_result))
 870                 goto nomatch;
 871
 872         /* import variables returned from program or or file into environment */
 873         if (rule->import.operation != KEY_OP_UNSET) {
 874                 char import[PATH_SIZE];
 875                 int rc = -1;
 876
 877                 strlcpy(import, key_val(rule, &rule->import), sizeof(import));
 878                 udev_rules_apply_format(udev, import, sizeof(import));
 879                 dbg("check for IMPORT import='%s'", import);
 880                 if (rule->import_type == IMPORT_PROGRAM) {
 881                         rc = import_program_into_env(udev, import);
 882                 } else if (rule->import_type == IMPORT_FILE) {
 883                         dbg("import file import='%s'", import);
 884                         rc = import_file_into_env(udev, import);
 885                 } else if (rule->import_type == IMPORT_PARENT) {
 886                         dbg("import parent import='%s'", import);
 887                         rc = import_parent_into_env(udev, import);
 888                 }
 889                 if (rc != 0) {
 890                         dbg("IMPORT failed");
 891                         if (rule->import.operation != KEY_OP_NOMATCH)
 892                                 goto nomatch;
 893                 } else
 894                         dbg("IMPORT '%s' imported", key_val(rule, &rule->import));
 895                 dbg("IMPORT key is true");
 896         }
 897
 898         /* rule matches, if we have ENV assignments export it */
 899         for (i = 0; i < rule->env.count; i++) {
 900                 struct key_pair *pair = &rule->env.keys[i];
 901
 902                 if (pair->key.operation == KEY_OP_ASSIGN) {
 903                         const char *key_name = key_pair_name(rule, pair);
 904                         const char *value = key_val(rule, &pair->key);
 905                         char *key_value = name_list_key_add(&udev->env_list, key_name, value);
 906                         if (key_value == NULL)
 907                                 break;
 908
 909                         udev_rules_apply_format(udev, key_value, NAME_SIZE);
 910                         putenv(key_value);
 911                         dbg("export ENV '%s'", key_value);
 912                 }
 913         }
 914
 915         return 0;
 916
 917 nomatch:
 918         return -1;
 919 }
 920
 921 int udev_rules_get_name(struct udev_rules *rules, struct udevice *udev)
 922 {
 923         struct udev_rule *rule;
 924         int name_set = 0;
 925
 926         dbg("udev->dev->devpath='%s'", udev->dev->devpath);
 927         dbg("udev->dev->kernel_name='%s'", udev->dev->kernel_name);
 928
 929         /* look for a matching rule to apply */
 930         udev_rules_iter_init(rules);
 931         while (1) {
 932                 rule = udev_rules_iter_next(rules);
 933                 if (rule == NULL)
 934                         break;
 935
 936                 if (name_set &&
 937                     (rule->name.operation == KEY_OP_ASSIGN ||
 938                      rule->name.operation == KEY_OP_ASSIGN_FINAL ||
 939                      rule->name.operation == KEY_OP_ADD)) {
 940                         dbg("node name already set, rule ignored");
 941                         continue;
 942                 }
 943
 944                 dbg("process rule");
 945                 if (match_rule(udev, rule) == 0) {
 946                         /* apply options */
 947                         if (rule->ignore_device) {
 948                                 info("rule applied, '%s' is ignored", udev->dev->kernel_name);
 949                                 udev->ignore_device = 1;
 950                                 return 0;
 951                         }
 952                         if (rule->ignore_remove) {
 953                                 udev->ignore_remove = 1;
 954                                 dbg("remove event should be ignored");
 955                         }
 956                         /* apply all_partitions option only at a main block device */
 957                         if (rule->partitions &&
 958                             strcmp(udev->dev->subsystem, "block") == 0 && udev->dev->kernel_number[0] == '\0') {
 959                                 udev->partitions = rule->partitions;
 960                                 dbg("creation of partition nodes requested");
 961                         }
 962
 963                         /* apply permissions */
 964                         if (!udev->mode_final && rule->mode != 0000) {
 965                                 if (rule->mode_operation == KEY_OP_ASSIGN_FINAL)
 966                                         udev->mode_final = 1;
 967                                 udev->mode = rule->mode;
 968                                 dbg("applied mode=%#o to '%s'", rule->mode, udev->dev->kernel_name);
 969                         }
 970                         if (!udev->owner_final && rule->owner.operation != KEY_OP_UNSET) {
 971                                 if (rule->owner.operation == KEY_OP_ASSIGN_FINAL)
 972                                         udev->owner_final = 1;
 973                                 strlcpy(udev->owner, key_val(rule, &rule->owner), sizeof(udev->owner));
 974                                 udev_rules_apply_format(udev, udev->owner, sizeof(udev->owner));
 975                                 dbg("applied owner='%s' to '%s'", udev->owner, udev->dev->kernel_name);
 976                         }
 977                         if (!udev->group_final && rule->group.operation != KEY_OP_UNSET) {
 978                                 if (rule->group.operation == KEY_OP_ASSIGN_FINAL)
 979                                         udev->group_final = 1;
 980                                 strlcpy(udev->group, key_val(rule, &rule->group), sizeof(udev->group));
 981                                 udev_rules_apply_format(udev, udev->group, sizeof(udev->group));
 982                                 dbg("applied group='%s' to '%s'", udev->group, udev->dev->kernel_name);
 983                         }
 984
 985                         /* collect symlinks */
 986                         if (!udev->symlink_final && rule->symlink.operation != KEY_OP_UNSET) {
 987                                 char temp[PATH_SIZE];
 988                                 char *pos, *next;
 989                                 int count;
 990
 991                                 if (rule->symlink.operation == KEY_OP_ASSIGN_FINAL)
 992                                         udev->symlink_final = 1;
 993                                 if (rule->symlink.operation == KEY_OP_ASSIGN || rule->symlink.operation == KEY_OP_ASSIGN_FINAL) {
 994                                         info("reset symlink list");
 995                                         name_list_cleanup(&udev->symlink_list);
 996                                 }
 997                                 strlcpy(temp, key_val(rule, &rule->symlink), sizeof(temp));
 998                                 udev_rules_apply_format(udev, temp, sizeof(temp));
 999                                 count = replace_untrusted_chars(temp);
1000                                 if (count)
1001                                         info("%i untrusted character(s) replaced" , count);
1002                                 dbg("rule applied, added symlink(s) '%s'", temp);
1003
1004                                 /* add multiple symlinks separated by spaces */
1005                                 pos = temp;
1006                                 while (isspace(pos[0]))
1007                                         pos++;
1008                                 next = strchr(pos, ' ');
1009                                 while (next) {
1010                                         next[0] = '\0';
1011                                         info("add symlink '%s'", pos);
1012                                         name_list_add(&udev->symlink_list, pos, 0);
1013                                         while (isspace(next[1]))
1014                                                 next++;
1015                                         pos = &next[1];
1016                                         next = strchr(pos, ' ');
1017                                 }
1018                                 if (pos[0] != '\0') {
1019                                         info("add symlink '%s'", pos);
1020                                         name_list_add(&udev->symlink_list, pos, 0);
1021                                 }
1022                         }
1023
1024                         /* set name, later rules with name set will be ignored */
1025                         if (rule->name.operation == KEY_OP_ASSIGN ||
1026                             rule->name.operation == KEY_OP_ASSIGN_FINAL ||
1027                             rule->name.operation == KEY_OP_ADD) {
1028                                 int count;
1029
1030                                 name_set = 1;
1031                                 strlcpy(udev->name, key_val(rule, &rule->name), sizeof(udev->name));
1032                                 udev_rules_apply_format(udev, udev->name, sizeof(udev->name));
1033                                 count = replace_untrusted_chars(udev->name);
1034                                 if (count)
1035                                         info("%i untrusted character(s) replaced", count);
1036
1037                                 info("rule applied, '%s' becomes '%s'", udev->dev->kernel_name, udev->name);
1038                                 if (strcmp(udev->dev->subsystem, "net") != 0)
1039                                         dbg("name, '%s' is going to have owner='%s', group='%s', mode=%#o partitions=%i",
1040                                             udev->name, udev->owner, udev->group, udev->mode, udev->partitions);
1041                         }
1042
1043                         if (!udev->run_final && rule->run.operation != KEY_OP_UNSET) {
1044                                 if (rule->run.operation == KEY_OP_ASSIGN_FINAL)
1045                                         udev->run_final = 1;
1046                                 if (rule->run.operation == KEY_OP_ASSIGN || rule->run.operation == KEY_OP_ASSIGN_FINAL) {
1047                                         info("reset run list");
1048                                         name_list_cleanup(&udev->run_list);
1049                                 }
1050                                 dbg("add run '%s'", key_val(rule, &rule->run));
1051                                 name_list_add(&udev->run_list, key_val(rule, &rule->run), 0);
1052                         }
1053
1054                         if (rule->last_rule) {
1055                                 dbg("last rule to be applied");
1056                                 break;
1057                         }
1058
1059                         if (rule->goto_label.operation != KEY_OP_UNSET) {
1060                                 dbg("moving forward to label '%s'", key_val(rule, &rule->goto_label));
1061                                 udev_rules_iter_label(rules, key_val(rule, &rule->goto_label));
1062                         }
1063                 }
1064         }
1065
1066         if (!name_set) {
1067                 strlcpy(udev->name, udev->dev->kernel_name, sizeof(udev->name));
1068                 info("no node name set, will use kernel name '%s'", udev->name);
1069         }
1070
1071         if (udev->tmp_node[0] != '\0') {
1072                 dbg("removing temporary device node");
1073                 unlink_secure(udev->tmp_node);
1074                 udev->tmp_node[0] = '\0';
1075         }
1076
1077         return 0;
1078 }
1079
1080 int udev_rules_get_run(struct udev_rules *rules, struct udevice *udev)
1081 {
1082         struct udev_rule *rule;
1083
1084         dbg("udev->kernel_name='%s'", udev->dev->kernel_name);
1085
1086         /* look for a matching rule to apply */
1087         udev_rules_iter_init(rules);
1088         while (1) {
1089                 rule = udev_rules_iter_next(rules);
1090                 if (rule == NULL)
1091                         break;
1092
1093                 dbg("process rule");
1094                 if (rule->name.operation != KEY_OP_UNSET || rule->symlink.operation != KEY_OP_UNSET ||
1095                     rule->mode_operation != KEY_OP_UNSET || rule->owner.operation != KEY_OP_UNSET || rule->group.operation != KEY_OP_UNSET) {
1096                         dbg("skip rule that names a device");
1097                         continue;
1098                 }
1099
1100                 if (match_rule(udev, rule) == 0) {
1101                         if (rule->ignore_device) {
1102                                 info("rule applied, '%s' is ignored", udev->dev->kernel_name);
1103                                 udev->ignore_device = 1;
1104                                 return 0;
1105                         }
1106
1107                         if (!udev->run_final && rule->run.operation != KEY_OP_UNSET) {
1108                                 if (rule->run.operation == KEY_OP_ASSIGN || rule->run.operation == KEY_OP_ASSIGN_FINAL) {
1109                                         info("reset run list");
1110                                         name_list_cleanup(&udev->run_list);
1111                                 }
1112                                 dbg("add run '%s'", key_val(rule, &rule->run));
1113                                 name_list_add(&udev->run_list, key_val(rule, &rule->run), 0);
1114                                 if (rule->run.operation == KEY_OP_ASSIGN_FINAL)
1115                                         break;
1116                         }
1117
1118                         if (rule->last_rule) {
1119                                 dbg("last rule to be applied");
1120                                 break;
1121                         }
1122
1123                         if (rule->goto_label.operation != KEY_OP_UNSET) {
1124                                 dbg("moving forward to label '%s'", key_val(rule, &rule->goto_label));
1125                                 udev_rules_iter_label(rules, key_val(rule, &rule->goto_label));
1126                         }
1127                 }
1128         }
1129
1130         return 0;
1131 }