udev_rules.c

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