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 #include <sys/stat.h>
  35
  36 #include "libsysfs/sysfs/libsysfs.h"
  37 #include "list.h"
  38 #include "udev_libc_wrapper.h"
  39 #include "udev.h"
  40 #include "udev_utils.h"
  41 #include "udev_version.h"
  42 #include "logging.h"
  43 #include "udev_rules.h"
  44 #include "udev_db.h"
  45
  46
  47 /* compare string with pattern (supports * ? [0-9] [!A-Z]) */
  48 static int strcmp_pattern(const char *p, const char *s)
  49 {
  50         if (s[0] == '\0') {
  51                 while (p[0] == '*')
  52                         p++;
  53                 return (p[0] != '\0');
  54         }
  55         switch (p[0]) {
  56         case '[':
  57                 {
  58                         int not = 0;
  59                         p++;
  60                         if (p[0] == '!') {
  61                                 not = 1;
  62                                 p++;
  63                         }
  64                         while ((p[0] != '\0') && (p[0] != ']')) {
  65                                 int match = 0;
  66                                 if (p[1] == '-') {
  67                                         if ((s[0] >= p[0]) && (s[0] <= p[2]))
  68                                                 match = 1;
  69                                         p += 3;
  70                                 } else {
  71                                         match = (p[0] == s[0]);
  72                                         p++;
  73                                 }
  74                                 if (match ^ not) {
  75                                         while ((p[0] != '\0') && (p[0] != ']'))
  76                                                 p++;
  77                                         if (p[0] == ']')
  78                                                 return strcmp_pattern(p+1, s+1);
  79                                 }
  80                         }
  81                 }
  82                 break;
  83         case '*':
  84                 if (strcmp_pattern(p, s+1))
  85                         return strcmp_pattern(p+1, s);
  86                 return 0;
  87         case '\0':
  88                 if (s[0] == '\0') {
  89                         return 0;
  90                 }
  91                 break;
  92         default:
  93                 if ((p[0] == s[0]) || (p[0] == '?'))
  94                         return strcmp_pattern(p+1, s+1);
  95                 break;
  96         }
  97         return 1;
  98 }
  99
 100 /* extract possible {attr} and move str behind it */
 101 static char *get_format_attribute(char **str)
 102 {
 103         char *pos;
 104         char *attr = NULL;
 105
 106         if (*str[0] == '{') {
 107                 pos = strchr(*str, '}');
 108                 if (pos == NULL) {
 109                         err("missing closing brace for format");
 110                         return NULL;
 111                 }
 112                 pos[0] = '\0';
 113                 attr = *str+1;
 114                 *str = pos+1;
 115                 dbg("attribute='%s', str='%s'", attr, *str);
 116         }
 117         return attr;
 118 }
 119
 120 /* extract possible format length and move str behind it*/
 121 static int get_format_len(char **str)
 122 {
 123         int num;
 124         char *tail;
 125
 126         if (isdigit(*str[0])) {
 127                 num = (int) strtoul(*str, &tail, 10);
 128                 if (num > 0) {
 129                         *str = tail;
 130                         dbg("format length=%i", num);
 131                         return num;
 132                 } else {
 133                         err("format parsing error '%s'", *str);
 134                 }
 135         }
 136         return -1;
 137 }
 138
 139 static int get_key(char **line, char **key, char **value)
 140 {
 141         char *linepos;
 142         char *temp;
 143
 144         linepos = *line;
 145         if (!linepos)
 146                 return -1;
 147
 148         if (strchr(linepos, '\\')) {
 149                 dbg("escaped characters are not supported, skip");
 150                 return -1;
 151         }
 152
 153         /* skip whitespace */
 154         while (isspace(linepos[0]))
 155                 linepos++;
 156
 157         /* get the key */
 158         *key = linepos;
 159         while (1) {
 160                 linepos++;
 161                 if (linepos[0] == '\0')
 162                         return -1;
 163                 if (isspace(linepos[0]))
 164                         break;
 165                 if (linepos[0] == '=')
 166                         break;
 167         }
 168
 169         /* terminate key */
 170         linepos[0] = '\0';
 171         linepos++;
 172
 173         /* skip whitespace */
 174         while (isspace(linepos[0]))
 175                 linepos++;
 176
 177         /* get the value*/
 178         if (linepos[0] == '"') {
 179                 linepos++;
 180                 temp = strchr(linepos, '"');
 181                 if (!temp) {
 182                         dbg("missing closing quote");
 183                         return -1;
 184                 }
 185                 dbg("value is quoted");
 186                 temp[0] = '\0';
 187         } else if (linepos[0] == '\'') {
 188                 linepos++;
 189                 temp = strchr(linepos, '\'');
 190                 if (!temp) {
 191                         dbg("missing closing quote");
 192                         return -1;
 193                 }
 194                 dbg("value is quoted");
 195                 temp[0] = '\0';
 196         } else if (linepos[0] == '\0') {
 197                 dbg("value is empty");
 198         } else {
 199                 temp = linepos;
 200                 while (temp[0] && !isspace(temp[0]))
 201                         temp++;
 202                 temp[0] = '\0';
 203         }
 204         *value = linepos;
 205
 206         return 0;
 207 }
 208
 209 static int import_keys_into_env(struct udevice *udev, const char *buf, size_t bufsize)
 210 {
 211         char line[LINE_SIZE];
 212         const char *bufline;
 213         char *linepos;
 214         char *variable;
 215         char *value;
 216         size_t cur;
 217         size_t count;
 218         int lineno;
 219
 220         /* loop through the whole buffer */
 221         lineno = 0;
 222         cur = 0;
 223         while (cur < bufsize) {
 224                 count = buf_get_line(buf, bufsize, cur);
 225                 bufline = &buf[cur];
 226                 cur += count+1;
 227                 lineno++;
 228
 229                 if (count >= sizeof(line)) {
 230                         err("line too long, conf line skipped %s, line %d", udev_config_filename, lineno);
 231                         continue;
 232                 }
 233
 234                 /* eat the whitespace */
 235                 while ((count > 0) && isspace(bufline[0])) {
 236                         bufline++;
 237                         count--;
 238                 }
 239                 if (count == 0)
 240                         continue;
 241
 242                 /* see if this is a comment */
 243                 if (bufline[0] == COMMENT_CHARACTER)
 244                         continue;
 245
 246                 strlcpy(line, bufline, count+1);
 247
 248                 linepos = line;
 249                 if (get_key(&linepos, &variable, &value) == 0) {
 250                         dbg("import '%s=%s'", variable, value);
 251                         name_list_key_add(&udev->env_list, variable, value);
 252                         setenv(variable, value, 1);
 253                 }
 254         }
 255
 256         return 0;
 257 }
 258
 259 static int import_file_into_env(struct udevice *udev, const char *filename)
 260 {
 261         char *buf;
 262         size_t bufsize;
 263
 264         if (file_map(filename, &buf, &bufsize) != 0) {
 265                 err("can't open '%s'", filename);
 266                 return -1;
 267         }
 268         import_keys_into_env(udev, buf, bufsize);
 269         file_unmap(buf, bufsize);
 270
 271         return 0;
 272 }
 273
 274 static int import_program_into_env(struct udevice *udev, const char *program)
 275 {
 276         char result[1024];
 277         size_t reslen;
 278
 279         if (execute_program(program, udev->subsystem, result, sizeof(result), &reslen) != 0)
 280                 return -1;
 281         return import_keys_into_env(udev, result, reslen);
 282 }
 283
 284 static int import_parent_into_env(struct udevice *udev, struct sysfs_class_device *class_dev, const char *filter)
 285 {
 286         struct sysfs_class_device *parent = sysfs_get_classdev_parent(class_dev);
 287         int rc = -1;
 288
 289         if (parent != NULL) {
 290                 struct udevice udev_parent;
 291                 struct name_entry *name_loop;
 292
 293                 dbg("found parent '%s', get the node name", parent->path);
 294                 udev_init_device(&udev_parent, NULL, NULL, NULL);
 295                 /* import the udev_db of the parent */
 296                 if (udev_db_get_device(&udev_parent, &parent->path[strlen(sysfs_path)]) == 0) {
 297                         dbg("import stored parent env '%s'", udev_parent.name);
 298                         list_for_each_entry(name_loop, &udev_parent.env_list, node) {
 299                                 char name[NAME_SIZE];
 300                                 char *pos;
 301
 302                                 strlcpy(name, name_loop->name, sizeof(name));
 303                                 pos = strchr(name, '=');
 304                                 if (pos) {
 305                                         pos[0] = '\0';
 306                                         pos++;
 307                                         if (strcmp_pattern(filter, name) == 0) {
 308                                                 dbg("import key '%s'", name_loop->name);
 309                                                 name_list_add(&udev->env_list, name_loop->name, 0);
 310                                                 setenv(name, pos, 1);
 311                                         } else
 312                                                 dbg("skip key '%s'", name_loop->name);
 313                                 }
 314                         }
 315                         rc = 0;
 316                 } else
 317                         dbg("parent not found in database");
 318                 udev_cleanup_device(&udev_parent);
 319         }
 320
 321         return rc;
 322 }
 323
 324 /* finds the lowest positive N such that <name>N isn't present in the udevdb
 325  * if <name> doesn't exist, 0 is returned, N otherwise
 326  */
 327 static int find_free_number(struct udevice *udev, const char *name)
 328 {
 329         char devpath[PATH_SIZE];
 330         char filename[PATH_SIZE];
 331         int num = 0;
 332
 333         strlcpy(filename, name, sizeof(filename));
 334         while (1) {
 335                 dbg("look for existing node '%s'", filename);
 336                 if (udev_db_search_name(devpath, sizeof(devpath), filename) != 0) {
 337                         dbg("free num=%d", num);
 338                         return num;
 339                 }
 340
 341                 num++;
 342                 if (num > 1000) {
 343                         info("find_free_number gone crazy (num=%d), aborted", num);
 344                         return -1;
 345                 }
 346                 snprintf(filename, sizeof(filename), "%s%d", name, num);
 347                 filename[sizeof(filename)-1] = '\0';
 348         }
 349 }
 350
 351 static int find_sysfs_attribute(struct sysfs_class_device *class_dev, struct sysfs_device *sysfs_device,
 352                                 const char *name, char *value, size_t len)
 353 {
 354         struct sysfs_attribute *tmpattr;
 355
 356         dbg("look for device attribute '%s'", name);
 357         if (class_dev) {
 358                 dbg("look for class attribute '%s/%s'", class_dev->path, name);
 359                 tmpattr = sysfs_get_classdev_attr(class_dev, name);
 360                 if (tmpattr)
 361                         goto attr_found;
 362         }
 363         if (sysfs_device) {
 364                 dbg("look for devices attribute '%s/%s'", sysfs_device->path, name);
 365                 tmpattr = sysfs_get_device_attr(sysfs_device, name);
 366                 if (tmpattr)
 367                         goto attr_found;
 368         }
 369         return -1;
 370
 371 attr_found:
 372         strlcpy(value, tmpattr->value, len);
 373         remove_trailing_char(value, '\n');
 374
 375         dbg("found attribute '%s'", tmpattr->path);
 376         return 0;
 377 }
 378
 379 #define WAIT_LOOP_PER_SECOND                    20
 380 static int wait_for_sysfs(struct udevice *udev, const char *file, int timeout)
 381 {
 382         char filename[PATH_SIZE];
 383         struct stat stats;
 384         int loop = timeout * WAIT_LOOP_PER_SECOND;
 385
 386         snprintf(filename, sizeof(filename), "%s%s/%s", sysfs_path, udev->devpath, file);
 387         filename[sizeof(filename)-1] = '\0';
 388         dbg("wait %i sec for '%s'", timeout, filename);
 389
 390         while (--loop) {
 391                 if (stat(filename, &stats) == 0) {
 392                         dbg("file appeared after %i loops", (timeout * WAIT_LOOP_PER_SECOND) - loop-1);
 393                         return 0;
 394                 }
 395                 usleep(1000 * 1000 / WAIT_LOOP_PER_SECOND);
 396         }
 397         dbg("waiting for '%s' failed", filename);
 398         return -1;
 399 }
 400
 401 static void apply_format(struct udevice *udev, char *string, size_t maxsize,
 402                          struct sysfs_class_device *class_dev, struct sysfs_device *sysfs_device)
 403 {
 404         char temp[PATH_SIZE];
 405         char temp2[PATH_SIZE];
 406         char *head, *tail, *pos, *cpos, *attr, *rest;
 407         int len;
 408         int i;
 409         unsigned int next_free_number;
 410         struct sysfs_class_device *class_dev_parent;
 411         enum subst_type {
 412                 SUBST_UNKNOWN,
 413                 SUBST_DEVPATH,
 414                 SUBST_ID,
 415                 SUBST_KERNEL_NUMBER,
 416                 SUBST_KERNEL_NAME,
 417                 SUBST_MAJOR,
 418                 SUBST_MINOR,
 419                 SUBST_RESULT,
 420                 SUBST_SYSFS,
 421                 SUBST_ENUM,
 422                 SUBST_PARENT,
 423                 SUBST_TEMP_NODE,
 424                 SUBST_ROOT,
 425                 SUBST_MODALIAS,
 426                 SUBST_ENV,
 427         };
 428         static const struct subst_map {
 429                 char *name;
 430                 char fmt;
 431                 enum subst_type type;
 432         } map[] = {
 433                 { .name = "devpath",            .fmt = 'p',     .type = SUBST_DEVPATH },
 434                 { .name = "id",                 .fmt = 'b',     .type = SUBST_ID },
 435                 { .name = "number",             .fmt = 'n',     .type = SUBST_KERNEL_NUMBER },
 436                 { .name = "kernel",             .fmt = 'k',     .type = SUBST_KERNEL_NAME },
 437                 { .name = "major",              .fmt = 'M',     .type = SUBST_MAJOR },
 438                 { .name = "minor",              .fmt = 'm',     .type = SUBST_MINOR },
 439                 { .name = "result",             .fmt = 'c',     .type = SUBST_RESULT },
 440                 { .name = "sysfs",              .fmt = 's',     .type = SUBST_SYSFS },
 441                 { .name = "enum",               .fmt = 'e',     .type = SUBST_ENUM },
 442                 { .name = "parent",             .fmt = 'P',     .type = SUBST_PARENT },
 443                 { .name = "tempnode",           .fmt = 'N',     .type = SUBST_TEMP_NODE },
 444                 { .name = "root",               .fmt = 'r',     .type = SUBST_ROOT },
 445                 { .name = "modalias",           .fmt = 'A',     .type = SUBST_MODALIAS },
 446                 { .name = "env",                .fmt = 'E',     .type = SUBST_ENV },
 447                 {}
 448         };
 449         enum subst_type type;
 450         const struct subst_map *subst;
 451
 452         head = string;
 453         while (1) {
 454                 len = -1;
 455                 while (head[0] != '\0') {
 456                         if (head[0] == '$') {
 457                                 /* substitute named variable */
 458                                 if (head[1] == '\0')
 459                                         break;
 460                                 if (head[1] == '$') {
 461                                         strlcpy(temp, head+2, sizeof(temp));
 462                                         strlcpy(head+1, temp, maxsize);
 463                                         head++;
 464                                         continue;
 465                                 }
 466                                 head[0] = '\0';
 467                                 for (subst = map; subst->name; subst++) {
 468                                         if (strncasecmp(&head[1], subst->name, strlen(subst->name)) == 0) {
 469                                                 type = subst->type;
 470                                                 tail = head + strlen(subst->name)+1;
 471                                                 dbg("will substitute format name '%s'", subst->name);
 472                                                 goto found;
 473                                         }
 474                                 }
 475                         }
 476                         else if (head[0] == '%') {
 477                                 /* substitute format char */
 478                                 if (head[1] == '\0')
 479                                         break;
 480                                 if (head[1] == '%') {
 481                                         strlcpy(temp, head+2, sizeof(temp));
 482                                         strlcpy(head+1, temp, maxsize);
 483                                         head++;
 484                                         continue;
 485                                 }
 486                                 head[0] = '\0';
 487                                 tail = head+1;
 488                                 len = get_format_len(&tail);
 489                                 for (subst = map; subst->name; subst++) {
 490                                         if (tail[0] == subst->fmt) {
 491                                                 type = subst->type;
 492                                                 tail++;
 493                                                 dbg("will substitute format char '%c'", subst->fmt);
 494                                                 goto found;
 495                                         }
 496                                 }
 497                         }
 498                         head++;
 499                 }
 500                 break;
 501 found:
 502                 attr = get_format_attribute(&tail);
 503                 strlcpy(temp, tail, sizeof(temp));
 504                 dbg("format=%i, string='%s', tail='%s', class_dev=%p, sysfs_dev=%p",
 505                     type ,string, tail, class_dev, sysfs_device);
 506
 507                 switch (type) {
 508                 case SUBST_DEVPATH:
 509                         strlcat(string, udev->devpath, maxsize);
 510                         dbg("substitute devpath '%s'", udev->devpath);
 511                         break;
 512                 case SUBST_ID:
 513                         strlcat(string, udev->bus_id, maxsize);
 514                         dbg("substitute bus_id '%s'", udev->bus_id);
 515                         break;
 516                 case SUBST_KERNEL_NAME:
 517                         strlcat(string, udev->kernel_name, maxsize);
 518                         dbg("substitute kernel name '%s'", udev->kernel_name);
 519                         break;
 520                 case SUBST_KERNEL_NUMBER:
 521                         strlcat(string, udev->kernel_number, maxsize);
 522                         dbg("substitute kernel number '%s'", udev->kernel_number);
 523                         break;
 524                 case SUBST_MAJOR:
 525                         sprintf(temp2, "%d", major(udev->devt));
 526                         strlcat(string, temp2, maxsize);
 527                         dbg("substitute major number '%s'", temp2);
 528                         break;
 529                 case SUBST_MINOR:
 530                         sprintf(temp2, "%d", minor(udev->devt));
 531                         strlcat(string, temp2, maxsize);
 532                         dbg("substitute minor number '%s'", temp2);
 533                         break;
 534                 case SUBST_RESULT:
 535                         if (udev->program_result[0] == '\0')
 536                                 break;
 537                         /* get part part of the result string */
 538                         i = 0;
 539                         if (attr != NULL)
 540                                 i = strtoul(attr, &rest, 10);
 541                         if (i > 0) {
 542                                 dbg("request part #%d of result string", i);
 543                                 cpos = udev->program_result;
 544                                 while (--i) {
 545                                         while (cpos[0] != '\0' && !isspace(cpos[0]))
 546                                                 cpos++;
 547                                         while (isspace(cpos[0]))
 548                                                 cpos++;
 549                                 }
 550                                 if (i > 0) {
 551                                         err("requested part of result string not found");
 552                                         break;
 553                                 }
 554                                 strlcpy(temp2, cpos, sizeof(temp2));
 555                                 /* %{2+}c copies the whole string from the second part on */
 556                                 if (rest[0] != '+') {
 557                                         cpos = strchr(temp2, ' ');
 558                                         if (cpos)
 559                                                 cpos[0] = '\0';
 560                                 }
 561                                 strlcat(string, temp2, maxsize);
 562                                 dbg("substitute part of result string '%s'", temp2);
 563                         } else {
 564                                 strlcat(string, udev->program_result, maxsize);
 565                                 dbg("substitute result string '%s'", udev->program_result);
 566                         }
 567                         break;
 568                 case SUBST_SYSFS:
 569                         if (attr == NULL) {
 570                                 dbg("missing attribute");
 571                                 break;
 572                         }
 573                         if (find_sysfs_attribute(class_dev, sysfs_device, attr, temp2, sizeof(temp2)) != 0) {
 574                                 struct sysfs_device *parent_device;
 575
 576                                 dbg("sysfs attribute '%s' not found, walk up the physical devices", attr);
 577                                 parent_device = sysfs_get_device_parent(sysfs_device);
 578                                 while (parent_device) {
 579                                         dbg("looking at '%s'", parent_device->path);
 580                                         if (find_sysfs_attribute(NULL, parent_device, attr, temp2, sizeof(temp2)) == 0)
 581                                                 break;
 582                                         parent_device = sysfs_get_device_parent(parent_device);
 583                                 }
 584                                 if (!parent_device)
 585                                         break;
 586                         }
 587                         /* strip trailing whitespace of sysfs value */
 588                         i = strlen(temp2);
 589                         while (i > 0 && isspace(temp2[i-1]))
 590                                 temp2[--i] = '\0';
 591                         replace_untrusted_chars(temp2);
 592                         strlcat(string, temp2, maxsize);
 593                         dbg("substitute sysfs value '%s'", temp2);
 594                         break;
 595                 case SUBST_ENUM:
 596                         next_free_number = find_free_number(udev, string);
 597                         if (next_free_number > 0) {
 598                                 sprintf(temp2, "%d", next_free_number);
 599                                 strlcat(string, temp2, maxsize);
 600                         }
 601                         break;
 602                 case SUBST_PARENT:
 603                         if (!class_dev)
 604                                 break;
 605                         class_dev_parent = sysfs_get_classdev_parent(class_dev);
 606                         if (class_dev_parent != NULL) {
 607                                 struct udevice udev_parent;
 608
 609                                 dbg("found parent '%s', get the node name", class_dev_parent->path);
 610                                 udev_init_device(&udev_parent, NULL, NULL, NULL);
 611                                 /* lookup the name in the udev_db with the DEVPATH of the parent */
 612                                 if (udev_db_get_device(&udev_parent, &class_dev_parent->path[strlen(sysfs_path)]) == 0) {
 613                                         strlcat(string, udev_parent.name, maxsize);
 614                                         dbg("substitute parent node name'%s'", udev_parent.name);
 615                                 } else
 616                                         dbg("parent not found in database");
 617                                 udev_cleanup_device(&udev_parent);
 618                         }
 619                         break;
 620                 case SUBST_TEMP_NODE:
 621                         if (udev->tmp_node[0] == '\0') {
 622                                 dbg("create temporary device node for callout");
 623                                 snprintf(udev->tmp_node, sizeof(udev->tmp_node), "%s/.tmp-%u-%u",
 624                                          udev_root, major(udev->devt), minor(udev->devt));
 625                                 udev->tmp_node[sizeof(udev->tmp_node)-1] = '\0';
 626                                 udev_make_node(udev, udev->tmp_node, udev->devt, 0600, 0, 0);
 627                         }
 628                         strlcat(string, udev->tmp_node, maxsize);
 629                         dbg("substitute temporary device node name '%s'", udev->tmp_node);
 630                         break;
 631                 case SUBST_ROOT:
 632                         strlcat(string, udev_root, maxsize);
 633                         dbg("substitute udev_root '%s'", udev_root);
 634                         break;
 635                 case SUBST_MODALIAS:
 636                         if (find_sysfs_attribute(NULL, sysfs_device, "modalias", temp2, sizeof(temp2)) != 0)
 637                                 break;
 638                         strlcat(string, temp2, maxsize);
 639                         dbg("substitute MODALIAS '%s'", temp2);
 640                         break;
 641                 case SUBST_ENV:
 642                         if (attr == NULL) {
 643                                 dbg("missing attribute");
 644                                 break;
 645                         }
 646                         pos = getenv(attr);
 647                         if (pos == NULL) {
 648                                 dbg("env '%s' not avialable", attr);
 649                                 break;
 650                         }
 651                         dbg("substitute env '%s=%s'", attr, pos);
 652                         strlcat(string, pos, maxsize);
 653                         break;
 654                 default:
 655                         err("unknown substitution type=%i", type);
 656                         break;
 657                 }
 658                 /* possibly truncate to format-char specified length */
 659                 if (len != -1) {
 660                         head[len] = '\0';
 661                         dbg("truncate to %i chars, subtitution string becomes '%s'", len, head);
 662                 }
 663                 strlcat(string, temp, maxsize);
 664         }
 665 }
 666
 667 static char *key_val(struct udev_rule *rule, struct key *key)
 668 {
 669         return rule->buf + key->val_off;
 670 }
 671
 672 static char *key_pair_name(struct udev_rule *rule, struct key_pair *pair)
 673 {
 674         return rule->buf + pair->key_name_off;
 675 }
 676
 677 static int match_key(const char *key_name, struct udev_rule *rule, struct key *key, const char *val)
 678 {
 679         int match;
 680         char value[PATH_SIZE];
 681         char *key_value;
 682         char *pos;
 683
 684         if (key->operation == KEY_OP_UNSET)
 685                 return 0;
 686
 687         strlcpy(value, rule->buf + key->val_off, sizeof(value));
 688         key_value = value;
 689
 690         dbg("key %s value='%s'", key_name, key_value);
 691         while (key_value) {
 692                 pos = strchr(key_value, '|');
 693                 if (pos) {
 694                         pos[0] = '\0';
 695                         pos++;
 696                 }
 697                 dbg("match %s '%s' <-> '%s'", key_name, key_value, val);
 698                 match = (strcmp_pattern(key_value, val) == 0);
 699                 if (match && (key->operation != KEY_OP_NOMATCH)) {
 700                         dbg("%s is true (matching value)", key_name);
 701                         return 0;
 702                 }
 703                 if (!match && (key->operation == KEY_OP_NOMATCH)) {
 704                         dbg("%s is true (non-matching value)", key_name);
 705                         return 0;
 706                 }
 707                 key_value = pos;
 708         }
 709         dbg("%s is false", key_name);
 710         return -1;
 711 }
 712
 713 static int match_rule(struct udevice *udev, struct udev_rule *rule,
 714                       struct sysfs_class_device *class_dev, struct sysfs_device *sysfs_device)
 715 {
 716         struct sysfs_device *parent_device = sysfs_device;
 717
 718         if (match_key("ACTION", rule, &rule->action, udev->action))
 719                 goto exit;
 720
 721         if (match_key("KERNEL", rule, &rule->kernel_name, udev->kernel_name))
 722                 goto exit;
 723
 724         if (match_key("SUBSYSTEM", rule, &rule->subsystem, udev->subsystem))
 725                 goto exit;
 726
 727         if (match_key("DEVPATH", rule, &rule->devpath, udev->devpath))
 728                 goto exit;
 729
 730         if (rule->modalias.operation != KEY_OP_UNSET) {
 731                 char value[NAME_SIZE];
 732
 733                 if (find_sysfs_attribute(NULL, sysfs_device, "modalias", value, sizeof(value)) != 0) {
 734                         dbg("MODALIAS value not found");
 735                         goto exit;
 736                 }
 737                 if (match_key("MODALIAS", rule, &rule->modalias, value))
 738                         goto exit;
 739         }
 740
 741         if (rule->env.count) {
 742                 int i;
 743
 744                 dbg("check %i ENV keys", rule->env.count);
 745                 for (i = 0; i < rule->env.count; i++) {
 746                         struct key_pair *pair = &rule->env.keys[i];
 747                         const char *key_name = key_pair_name(rule, pair);
 748                         const char *value = getenv(key_name);
 749
 750                         if (!value) {
 751                                 dbg("ENV{'%s'} is not set", key_name);
 752                                 value = "";
 753                         }
 754                         if (match_key("ENV", rule, &pair->key, value))
 755                                 goto exit;
 756                 }
 757                 dbg("all %i ENV keys matched", rule->env.count);
 758         }
 759
 760         if (rule->wait_for_sysfs.operation != KEY_OP_UNSET) {
 761                 int match;
 762
 763                 match = (wait_for_sysfs(udev, key_val(rule, &rule->wait_for_sysfs), 3) == 0);
 764                 if (match && (rule->wait_for_sysfs.operation != KEY_OP_NOMATCH)) {
 765                         dbg("WAIT_FOR_SYSFS is true (matching value)");
 766                         return 0;
 767                 }
 768                 if (!match && (rule->wait_for_sysfs.operation == KEY_OP_NOMATCH)) {
 769                         dbg("WAIT_FOR_SYSFS is true, (non matching value)");
 770                         return 0;
 771                 }
 772                 dbg("WAIT_FOR_SYSFS is false");
 773                 return -1;
 774         }
 775
 776         /* walk up the chain of physical devices and find a match */
 777         while (1) {
 778                 /* check for matching driver */
 779                 if (rule->driver.operation != KEY_OP_UNSET) {
 780                         if (parent_device == NULL) {
 781                                 dbg("device has no sysfs_device");
 782                                 goto exit;
 783                         }
 784                         if (match_key("DRIVER", rule, &rule->driver, parent_device->driver_name))
 785                                 goto try_parent;
 786                 }
 787
 788                 /* check for matching bus value */
 789                 if (rule->bus.operation != KEY_OP_UNSET) {
 790                         if (parent_device == NULL) {
 791                                 dbg("device has no sysfs_device");
 792                                 goto exit;
 793                         }
 794                         if (match_key("BUS", rule, &rule->bus, parent_device->bus))
 795                                 goto try_parent;
 796                 }
 797
 798                 /* check for matching bus id */
 799                 if (rule->id.operation != KEY_OP_UNSET) {
 800                         if (parent_device == NULL) {
 801                                 dbg("device has no sysfs_device");
 802                                 goto exit;
 803                         }
 804                         if (match_key("ID", rule, &rule->id, parent_device->bus_id))
 805                                 goto try_parent;
 806                 }
 807
 808                 /* check for matching sysfs pairs */
 809                 if (rule->sysfs.count) {
 810                         int i;
 811
 812                         dbg("check %i SYSFS keys", rule->sysfs.count);
 813                         for (i = 0; i < rule->sysfs.count; i++) {
 814                                 struct key_pair *pair = &rule->sysfs.keys[i];
 815                                 const char *key_name = key_pair_name(rule, pair);
 816                                 const char *key_value = key_val(rule, &pair->key);
 817                                 char value[VALUE_SIZE];
 818                                 size_t len;
 819
 820                                 if (find_sysfs_attribute(class_dev, parent_device, key_name, value, sizeof(value)) != 0)
 821                                         goto try_parent;
 822
 823                                 /* strip trailing whitespace of value, if not asked to match for it */
 824                                 len = strlen(key_value);
 825                                 if (len && !isspace(key_value[len-1])) {
 826                                         len = strlen(value);
 827                                         while (len > 0 && isspace(value[len-1]))
 828                                                 value[--len] = '\0';
 829                                         dbg("removed %zi trailing whitespace chars from '%s'", strlen(value)-len, value);
 830                                 }
 831
 832                                 if (match_key("SYSFS", rule, &pair->key, value))
 833                                         goto try_parent;
 834                         }
 835                         dbg("all %i SYSFS keys matched", rule->sysfs.count);
 836                 }
 837
 838                 /* found matching physical device  */
 839                 break;
 840 try_parent:
 841                 dbg("try parent sysfs device");
 842                 parent_device = sysfs_get_device_parent(parent_device);
 843                 if (parent_device == NULL)
 844                         goto exit;
 845                 dbg("look at sysfs_device->path='%s'", parent_device->path);
 846                 dbg("look at sysfs_device->bus_id='%s'", parent_device->bus_id);
 847         }
 848
 849         /* import variables from file into environment */
 850         if (rule->import.operation != KEY_OP_UNSET) {
 851                 char import[PATH_SIZE];
 852                 int rc = -1;
 853
 854                 strlcpy(import, key_val(rule, &rule->import), sizeof(import));
 855                 apply_format(udev, import, sizeof(import), class_dev, sysfs_device);
 856                 dbg("check for IMPORT import='%s'", import);
 857                 if (rule->import_type == IMPORT_PROGRAM) {
 858                         dbg("run executable file import='%s'", import);
 859                         rc = import_program_into_env(udev, import);
 860                 } else if (rule->import_type == IMPORT_FILE) {
 861                         dbg("import file import='%s'", import);
 862                         rc = import_file_into_env(udev, import);
 863                 } else if (rule->import_type == IMPORT_PARENT && class_dev) {
 864                         dbg("import parent import='%s'", import);
 865                         rc = import_parent_into_env(udev, class_dev, import);
 866                 }
 867                 if (rc) {
 868                         dbg("IMPORT failed");
 869                         if (rule->import.operation != KEY_OP_NOMATCH)
 870                                 goto exit;
 871                 } else
 872                         dbg("IMPORT '%s' imported", key_val(rule, &rule->import));
 873                 dbg("IMPORT key is true");
 874         }
 875
 876         /* execute external program */
 877         if (rule->program.operation != KEY_OP_UNSET) {
 878                 char program[PATH_SIZE];
 879                 char result[PATH_SIZE];
 880
 881                 strlcpy(program, key_val(rule, &rule->program), sizeof(program));
 882                 apply_format(udev, program, sizeof(program), class_dev, sysfs_device);
 883                 dbg("check for PROGRAM program='%s", program);
 884                 if (execute_program(program, udev->subsystem, result, sizeof(result), NULL) != 0) {
 885                         dbg("PROGRAM is false");
 886                         if (rule->program.operation != KEY_OP_NOMATCH)
 887                                 goto exit;
 888                 } else {
 889                         dbg("PROGRAM matches");
 890                         remove_trailing_char(result, '\n');
 891                         replace_untrusted_chars(result);
 892                         dbg("result is '%s'", result);
 893                         strlcpy(udev->program_result, result, sizeof(udev->program_result));
 894                         dbg("PROGRAM returned successful");
 895                         if (rule->program.operation == KEY_OP_NOMATCH)
 896                                 goto exit;
 897                 }
 898                 dbg("PROGRAM key is true");
 899         }
 900
 901         /* check for matching result of external program */
 902         if (match_key("RESULT", rule, &rule->result, udev->program_result))
 903                 goto exit;
 904
 905         /* rule matches */
 906         return 0;
 907
 908 exit:
 909         return -1;
 910 }
 911
 912 int udev_rules_get_name(struct udev_rules *rules, struct udevice *udev, struct sysfs_class_device *class_dev)
 913 {
 914         struct sysfs_class_device *class_dev_parent;
 915         struct sysfs_device *sysfs_device = NULL;
 916         struct udev_rule *rule;
 917         int name_set = 0;
 918
 919         dbg("class_dev->name='%s'", class_dev->name);
 920
 921         /* Figure out where the "device"-symlink is at.  For char devices this will
 922          * always be in the class_dev->path.  On block devices, only the main block
 923          * device will have the device symlink in it's path. All partition devices
 924          * need to look at the symlink in its parent directory.
 925          */
 926         class_dev_parent = sysfs_get_classdev_parent(class_dev);
 927         if (class_dev_parent != NULL) {
 928                 dbg("given class device has a parent, use this instead");
 929                 sysfs_device = sysfs_get_classdev_device(class_dev_parent);
 930         } else {
 931                 sysfs_device = sysfs_get_classdev_device(class_dev);
 932         }
 933
 934         if (sysfs_device) {
 935                 dbg("found devices device: path='%s', bus_id='%s', bus='%s'",
 936                     sysfs_device->path, sysfs_device->bus_id, sysfs_device->bus);
 937                 strlcpy(udev->bus_id, sysfs_device->bus_id, sizeof(udev->bus_id));
 938         }
 939
 940         dbg("udev->kernel_name='%s'", udev->kernel_name);
 941
 942         /* look for a matching rule to apply */
 943         udev_rules_iter_init(rules);
 944         while (1) {
 945                 rule = udev_rules_iter_next(rules);
 946                 if (rule == NULL)
 947                         break;
 948
 949                 if (name_set && rule->name.operation != KEY_OP_UNSET) {
 950                         dbg("node name already set, rule ignored");
 951                         continue;
 952                 }
 953
 954                 dbg("process rule");
 955                 if (match_rule(udev, rule, class_dev, sysfs_device) == 0) {
 956                         /* apply options */
 957                         if (rule->ignore_device) {
 958                                 info("rule applied, '%s' is ignored", udev->kernel_name);
 959                                 udev->ignore_device = 1;
 960                                 return 0;
 961                         }
 962                         if (rule->ignore_remove) {
 963                                 udev->ignore_remove = 1;
 964                                 dbg("remove event should be ignored");
 965                         }
 966                         /* apply all_partitions option only at a main block device */
 967                         if (rule->partitions && udev->type == DEV_BLOCK && udev->kernel_number[0] == '\0') {
 968                                 udev->partitions = rule->partitions;
 969                                 dbg("creation of partition nodes requested");
 970                         }
 971
 972                         /* apply permissions */
 973                         if (!udev->mode_final && rule->mode != 0000) {
 974                                 if (rule->mode_operation == KEY_OP_ASSIGN_FINAL)
 975                                         udev->mode_final = 1;
 976                                 udev->mode = rule->mode;
 977                                 dbg("applied mode=%#o to '%s'", rule->mode, udev->kernel_name);
 978                         }
 979                         if (!udev->owner_final && rule->owner.operation != KEY_OP_UNSET) {
 980                                 if (rule->owner.operation == KEY_OP_ASSIGN_FINAL)
 981                                         udev->owner_final = 1;
 982                                 strlcpy(udev->owner, key_val(rule, &rule->owner), sizeof(udev->owner));
 983                                 apply_format(udev, udev->owner, sizeof(udev->owner), class_dev, sysfs_device);
 984                                 dbg("applied owner='%s' to '%s'", udev->owner, udev->kernel_name);
 985                         }
 986                         if (!udev->group_final && rule->group.operation != KEY_OP_UNSET) {
 987                                 if (rule->group.operation == KEY_OP_ASSIGN_FINAL)
 988                                         udev->group_final = 1;
 989                                 strlcpy(udev->group, key_val(rule, &rule->group), sizeof(udev->group));
 990                                 apply_format(udev, udev->group, sizeof(udev->group), class_dev, sysfs_device);
 991                                 dbg("applied group='%s' to '%s'", udev->group, udev->kernel_name);
 992                         }
 993
 994                         /* collect symlinks */
 995                         if (!udev->symlink_final && rule->symlink.operation != KEY_OP_UNSET) {
 996                                 char temp[PATH_SIZE];
 997                                 char *pos, *next;
 998
 999                                 if (rule->symlink.operation == KEY_OP_ASSIGN_FINAL)
1000                                         udev->symlink_final = 1;
1001                                 if (rule->symlink.operation == KEY_OP_ASSIGN || rule->symlink.operation == KEY_OP_ASSIGN_FINAL) {
1002                                         struct name_entry *name_loop;
1003                                         struct name_entry *temp_loop;
1004
1005                                         info("reset symlink list");
1006                                         list_for_each_entry_safe(name_loop, temp_loop, &udev->symlink_list, node) {
1007                                                 list_del(&name_loop->node);
1008                                                 free(name_loop);
1009                                         }
1010                                 }
1011                                 strlcpy(temp, key_val(rule, &rule->symlink), sizeof(temp));
1012                                 apply_format(udev, temp, sizeof(temp), class_dev, sysfs_device);
1013                                 info("rule applied, added symlink '%s'", temp);
1014
1015                                 /* add multiple symlinks separated by spaces */
1016                                 pos = temp;
1017                                 while (isspace(pos[0]))
1018                                         pos++;
1019                                 next = strchr(pos, ' ');
1020                                 while (next) {
1021                                         next[0] = '\0';
1022                                         info("add symlink '%s'", pos);
1023                                         name_list_add(&udev->symlink_list, pos, 0);
1024                                         while (isspace(next[1]))
1025                                                 next++;
1026                                         pos = &next[1];
1027                                         next = strchr(pos, ' ');
1028                                 }
1029                                 if (pos[0] != '\0') {
1030                                         info("add symlink '%s'", pos);
1031                                         name_list_add(&udev->symlink_list, pos, 0);
1032                                 }
1033                         }
1034
1035                         /* set name, later rules with name set will be ignored */
1036                         if (rule->name.operation != KEY_OP_UNSET) {
1037                                 name_set = 1;
1038                                 strlcpy(udev->name, key_val(rule, &rule->name), sizeof(udev->name));
1039                                 apply_format(udev, udev->name, sizeof(udev->name), class_dev, sysfs_device);
1040
1041                                 info("rule applied, '%s' becomes '%s'", udev->kernel_name, udev->name);
1042                                 if (udev->type != DEV_NET)
1043                                         dbg("name, '%s' is going to have owner='%s', group='%s', mode=%#o partitions=%i",
1044                                             udev->name, udev->owner, udev->group, udev->mode, udev->partitions);
1045                         }
1046
1047                         if (!udev->run_final && rule->run.operation != KEY_OP_UNSET) {
1048                                 char program[PATH_SIZE];
1049
1050                                 if (rule->run.operation == KEY_OP_ASSIGN_FINAL)
1051                                         udev->run_final = 1;
1052                                 if (rule->run.operation == KEY_OP_ASSIGN || rule->run.operation == KEY_OP_ASSIGN_FINAL) {
1053                                         struct name_entry *name_loop;
1054                                         struct name_entry *temp_loop;
1055
1056                                         info("reset run list");
1057                                         list_for_each_entry_safe(name_loop, temp_loop, &udev->run_list, node) {
1058                                                 list_del(&name_loop->node);
1059                                                 free(name_loop);
1060                                         }
1061                                 }
1062                                 strlcpy(program, key_val(rule, &rule->run), sizeof(program));
1063                                 apply_format(udev, program, sizeof(program), class_dev, sysfs_device);
1064                                 dbg("add run '%s'", program);
1065                                 name_list_add(&udev->run_list, program, 0);
1066                         }
1067
1068                         if (rule->last_rule) {
1069                                 dbg("last rule to be applied");
1070                                 break;
1071                         }
1072
1073                         if (rule->goto_label.operation != KEY_OP_UNSET) {
1074                                 dbg("moving forward to label '%s'", key_val(rule, &rule->goto_label));
1075                                 udev_rules_iter_label(rules, key_val(rule, &rule->goto_label));
1076                         }
1077                 }
1078         }
1079
1080         if (!name_set) {
1081                 strlcpy(udev->name, udev->kernel_name, sizeof(udev->name));
1082                 info("no rule found, will use kernel name '%s'", udev->name);
1083         }
1084
1085         if (udev->tmp_node[0] != '\0') {
1086                 dbg("removing temporary device node");
1087                 unlink_secure(udev->tmp_node);
1088                 udev->tmp_node[0] = '\0';
1089         }
1090
1091         return 0;
1092 }
1093
1094 int udev_rules_get_run(struct udev_rules *rules, struct udevice *udev,
1095                        struct sysfs_class_device *class_dev, struct sysfs_device *sysfs_dev)
1096 {
1097         struct udev_rule *rule;
1098
1099         if (class_dev && !sysfs_dev)
1100                 sysfs_dev = sysfs_get_classdev_device(class_dev);
1101         if (sysfs_dev) {
1102                 dbg("found devices device: path='%s', bus_id='%s', bus='%s'",
1103                     sysfs_dev->path, sysfs_dev->bus_id, sysfs_dev->bus);
1104                 strlcpy(udev->bus_id, sysfs_dev->bus_id, sizeof(udev->bus_id));
1105         }
1106
1107         dbg("udev->kernel_name='%s'", udev->kernel_name);
1108
1109         /* look for a matching rule to apply */
1110         udev_rules_iter_init(rules);
1111         while (1) {
1112                 rule = udev_rules_iter_next(rules);
1113                 if (rule == NULL)
1114                         break;
1115
1116                 dbg("process rule");
1117                 if (rule->name.operation != KEY_OP_UNSET || rule->symlink.operation != KEY_OP_UNSET ||
1118                     rule->mode_operation != KEY_OP_UNSET || rule->owner.operation != KEY_OP_UNSET || rule->group.operation != KEY_OP_UNSET) {
1119                         dbg("skip rule that names a device");
1120                         continue;
1121                 }
1122
1123                 if (match_rule(udev, rule, class_dev, sysfs_dev) == 0) {
1124                         if (rule->ignore_device) {
1125                                 info("rule applied, '%s' is ignored", udev->kernel_name);
1126                                 udev->ignore_device = 1;
1127                                 return 0;
1128                         }
1129
1130                         if (!udev->run_final && rule->run.operation != KEY_OP_UNSET) {
1131                                 char program[PATH_SIZE];
1132
1133                                 if (rule->run.operation == KEY_OP_ASSIGN || rule->run.operation == KEY_OP_ASSIGN_FINAL) {
1134                                         struct name_entry *name_loop;
1135                                         struct name_entry *temp_loop;
1136
1137                                         info("reset run list");
1138                                         list_for_each_entry_safe(name_loop, temp_loop, &udev->run_list, node) {
1139                                                 list_del(&name_loop->node);
1140                                                 free(name_loop);
1141                                         }
1142                                 }
1143                                 strlcpy(program, key_val(rule, &rule->run), sizeof(program));
1144                                 apply_format(udev, program, sizeof(program), class_dev, sysfs_dev);
1145                                 dbg("add run '%s'", program);
1146                                 name_list_add(&udev->run_list, program, 0);
1147                                 if (rule->run.operation == KEY_OP_ASSIGN_FINAL)
1148                                         break;
1149                         }
1150
1151                         if (rule->last_rule) {
1152                                 dbg("last rule to be applied");
1153                                 break;
1154                         }
1155
1156                         if (rule->goto_label.operation != KEY_OP_UNSET) {
1157                                 dbg("moving forward to label '%s'", key_val(rule, &rule->goto_label));
1158                                 udev_rules_iter_label(rules, key_val(rule, &rule->goto_label));
1159                         }
1160                 }
1161         }
1162
1163         return 0;
1164 }