udev_rules.c

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