namedev.c

   1 /*
   2  * namedev.c
   3  *
   4  * Userspace devfs
   5  *
   6  * Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com>
   7  *
   8  *
   9  *      This program is free software; you can redistribute it and/or modify it
  10  *      under the terms of the GNU General Public License as published by the
  11  *      Free Software Foundation version 2 of the License.
  12  *
  13  *      This program is distributed in the hope that it will be useful, but
  14  *      WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  *      General Public License for more details.
  17  *
  18  *      You should have received a copy of the GNU General Public License along
  19  *      with this program; if not, write to the Free Software Foundation, Inc.,
  20  *      675 Mass Ave, Cambridge, MA 02139, USA.
  21  *
  22  */
  23
  24 #include <stddef.h>
  25 #include <stdlib.h>
  26 #include <string.h>
  27 #include <stdio.h>
  28 #include <fcntl.h>
  29 #include <ctype.h>
  30 #include <unistd.h>
  31 #include <errno.h>
  32 #include <sys/wait.h>
  33
  34 #include "list.h"
  35 #include "udev.h"
  36 #include "udev_version.h"
  37 #include "namedev.h"
  38 #include "libsysfs/libsysfs.h"
  39 #include "klibc_fixups.h"
  40
  41 LIST_HEAD(config_device_list);
  42 LIST_HEAD(perm_device_list);
  43
  44 /* compare string with pattern (supports * ? [0-9] [!A-Z]) */
  45 static int strcmp_pattern(const char *p, const char *s)
  46 {
  47         if (*s == '\0') {
  48                 while (*p == '*')
  49                         p++;
  50                 return (*p != '\0');
  51         }
  52         switch (*p) {
  53         case '[':
  54                 {
  55                         int not = 0;
  56                         p++;
  57                         if (*p == '!') {
  58                                 not = 1;
  59                                 p++;
  60                         }
  61                         while (*p && (*p != ']')) {
  62                                 int match = 0;
  63                                 if (p[1] == '-') {
  64                                         if ((*s >= *p) && (*s <= p[2]))
  65                                                 match = 1;
  66                                         p += 3;
  67                                 } else {
  68                                         match = (*p == *s);
  69                                         p++;
  70                                 }
  71                                 if (match ^ not) {
  72                                         while (*p && (*p != ']'))
  73                                                 p++;
  74                                         return strcmp_pattern(p+1, s+1);
  75                                 }
  76                         }
  77                 }
  78                 break;
  79         case '*':
  80                 if (strcmp_pattern(p, s+1))
  81                         return strcmp_pattern(p+1, s);
  82                 return 0;
  83         case '\0':
  84                 if (*s == '\0') {
  85                         return 0;
  86                 }
  87                 break;
  88         default:
  89                 if ((*p == *s) || (*p == '?'))
  90                         return strcmp_pattern(p+1, s+1);
  91                 break;
  92         }
  93         return 1;
  94 }
  95
  96 #define copy_var(a, b, var)             \
  97         if (b->var)                     \
  98                 a->var = b->var;
  99
 100 #define copy_string(a, b, var)          \
 101         if (strlen(b->var))             \
 102                 strcpy(a->var, b->var);
 103
 104 int add_config_dev(struct config_device *new_dev)
 105 {
 106         struct list_head *tmp;
 107         struct config_device *tmp_dev;
 108
 109         /* update the values if we already have the device */
 110         list_for_each(tmp, &config_device_list) {
 111                 struct config_device *dev = list_entry(tmp, struct config_device, node);
 112                 if (strcmp_pattern(new_dev->name, dev->name))
 113                         continue;
 114                 if (strncmp(dev->bus, new_dev->bus, sizeof(dev->name)))
 115                         continue;
 116                 copy_var(dev, new_dev, type);
 117                 copy_string(dev, new_dev, bus);
 118                 copy_string(dev, new_dev, sysfs_file);
 119                 copy_string(dev, new_dev, sysfs_value);
 120                 copy_string(dev, new_dev, id);
 121                 copy_string(dev, new_dev, place);
 122                 copy_string(dev, new_dev, kernel_name);
 123                 copy_string(dev, new_dev, exec_program);
 124                 copy_string(dev, new_dev, symlink);
 125                 return 0;
 126         }
 127
 128         /* not found, add new structure to the device list */
 129         tmp_dev = malloc(sizeof(*tmp_dev));
 130         if (!tmp_dev)
 131                 return -ENOMEM;
 132         memcpy(tmp_dev, new_dev, sizeof(*tmp_dev));
 133         list_add_tail(&tmp_dev->node, &config_device_list);
 134         //dump_config_dev(tmp_dev);
 135         return 0;
 136 }
 137
 138 int add_perm_dev(struct perm_device *new_dev)
 139 {
 140         struct list_head *tmp;
 141         struct perm_device *tmp_dev;
 142
 143         /* update the values if we already have the device */
 144         list_for_each(tmp, &perm_device_list) {
 145                 struct perm_device *dev = list_entry(tmp, struct perm_device, node);
 146                 if (strcmp_pattern(new_dev->name, dev->name))
 147                         continue;
 148                 copy_var(dev, new_dev, mode);
 149                 copy_string(dev, new_dev, owner);
 150                 copy_string(dev, new_dev, group);
 151                 return 0;
 152         }
 153
 154         /* not found, add new structure to the perm list */
 155         tmp_dev = malloc(sizeof(*tmp_dev));
 156         if (!tmp_dev)
 157                 return -ENOMEM;
 158         memcpy(tmp_dev, new_dev, sizeof(*tmp_dev));
 159         list_add_tail(&tmp_dev->node, &perm_device_list);
 160         //dump_perm_dev(tmp_dev);
 161         return 0;
 162 }
 163
 164 static struct perm_device *find_perm(char *name)
 165 {
 166         struct list_head *tmp;
 167         struct perm_device *perm = NULL;
 168
 169         list_for_each(tmp, &perm_device_list) {
 170                 perm = list_entry(tmp, struct perm_device, node);
 171                 if (strcmp_pattern(perm->name, name))
 172                         continue;
 173                 return perm;
 174         }
 175         return NULL;
 176 }
 177
 178 static mode_t get_default_mode(struct sysfs_class_device *class_dev)
 179 {
 180         mode_t mode = 0600;     /* default to owner rw only */
 181
 182         if (strlen(default_mode_str) != 0) {
 183                 mode = strtol(default_mode_str, NULL, 8);
 184         }
 185         return mode;
 186 }
 187
 188 static void build_kernel_number(struct sysfs_class_device *class_dev, struct udevice *udev)
 189 {
 190         char *dig;
 191
 192         /* FIXME, figure out how to handle stuff like sdaj which will not work right now. */
 193         dig = class_dev->name + strlen(class_dev->name);
 194         while (isdigit(*(dig-1)))
 195                 dig--;
 196         strfieldcpy(udev->kernel_number, dig);
 197         dbg("kernel_number='%s'", udev->kernel_number);
 198 }
 199
 200 static void apply_format(struct udevice *udev, unsigned char *string)
 201 {
 202         char name[NAME_SIZE];
 203         char *pos;
 204
 205         while (1) {
 206                 pos = strchr(string, '%');
 207
 208                 if (pos) {
 209                         strfieldcpy(name, pos+2);
 210                         *pos = 0x00;
 211                         switch (pos[1]) {
 212                         case 'b':
 213                                 if (strlen(udev->bus_id) == 0)
 214                                         break;
 215                                 strcat(pos, udev->bus_id);
 216                                 dbg("substitute bus_id '%s'", udev->bus_id);
 217                                 break;
 218                         case 'n':
 219                                 if (strlen(udev->kernel_number) == 0)
 220                                         break;
 221                                 strcat(pos, udev->kernel_number);
 222                                 dbg("substitute kernel number '%s'", udev->kernel_number);
 223                                 break;
 224                         case 'D':
 225                                 if (strlen(udev->kernel_number) == 0) {
 226                                         strcat(pos, "disc");
 227                                         break;
 228                                 }
 229                                 strcat(pos, "part");
 230                                 strcat(pos, udev->kernel_number);
 231                                 dbg("substitute kernel number '%s'", udev->kernel_number);
 232                                 break;
 233                         case 'm':
 234                                 sprintf(pos, "%u", udev->minor);
 235                                 dbg("substitute minor number '%u'", udev->minor);
 236                                 break;
 237                         case 'M':
 238                                 sprintf(pos, "%u", udev->major);
 239                                 dbg("substitute major number '%u'", udev->major);
 240                                 break;
 241                         case 'c':
 242                                 if (strlen(udev->callout_value) == 0)
 243                                         break;
 244                                 strcat(pos, udev->callout_value);
 245                                 dbg("substitute callout output '%s'", udev->callout_value);
 246                                 break;
 247                         default:
 248                                 dbg("unknown substitution type '%%%c'", pos[1]);
 249                                 break;
 250                         }
 251                         strcat(string, name);
 252                 } else
 253                         break;
 254         }
 255 }
 256
 257
 258 static int exec_callout(struct config_device *dev, char *value, int len)
 259 {
 260         int retval;
 261         int res;
 262         int status;
 263         int fds[2];
 264         pid_t pid;
 265         int value_set = 0;
 266         char buffer[256];
 267         char *pos;
 268         char *args[CALLOUT_MAXARG];
 269         int i;
 270
 271         dbg("callout to '%s'", dev->exec_program);
 272         retval = pipe(fds);
 273         if (retval != 0) {
 274                 dbg("pipe failed");
 275                 return -1;
 276         }
 277         pid = fork();
 278         if (pid == -1) {
 279                 dbg("fork failed");
 280                 return -1;
 281         }
 282
 283         if (pid == 0) {
 284                 /* child */
 285                 close(STDOUT_FILENO);
 286                 dup(fds[1]);    /* dup write side of pipe to STDOUT */
 287                 if (strchr(dev->exec_program, ' ')) {
 288                         /* callout with arguments */
 289                         pos = dev->exec_program;
 290                         for (i=0; i < CALLOUT_MAXARG-1; i++) {
 291                                 args[i] = strsep(&pos, " ");
 292                                 if (args[i] == NULL)
 293                                         break;
 294                         }
 295                         if (args[i]) {
 296                                 dbg("too many args - %d", i);
 297                                 args[i] = NULL;
 298                         }
 299                         retval = execve(args[0], args, main_envp);
 300                 } else {
 301                         retval = execve(dev->exec_program, main_argv, main_envp);
 302                 }
 303                 if (retval != 0) {
 304                         dbg("child execve failed");
 305                         exit(1);
 306                 }
 307                 return -1; /* avoid compiler warning */
 308         } else {
 309                 /* parent reads from fds[0] */
 310                 close(fds[1]);
 311                 retval = 0;
 312                 while (1) {
 313                         res = read(fds[0], buffer, sizeof(buffer) - 1);
 314                         if (res <= 0)
 315                                 break;
 316                         buffer[res] = '\0';
 317                         if (res > len) {
 318                                 dbg("callout len %d too short", len);
 319                                 retval = -1;
 320                         }
 321                         if (value_set) {
 322                                 dbg("callout value already set");
 323                                 retval = -1;
 324                         } else {
 325                                 value_set = 1;
 326                                 strncpy(value, buffer, len);
 327                                 pos = value + strlen(value)-1;
 328                                 if (pos[0] == '\n')
 329                                 pos[0] = '\0';
 330                                 dbg("callout returned '%s'", value);
 331                         }
 332                 }
 333                 close(fds[0]);
 334                 res = wait(&status);
 335                 if (res < 0) {
 336                         dbg("wait failed result %d", res);
 337                         retval = -1;
 338                 }
 339
 340 #ifndef __KLIBC__
 341                 if (!WIFEXITED(status) || (WEXITSTATUS(status) != 0)) {
 342                         dbg("callout program status 0x%x", status);
 343                         retval = -1;
 344                 }
 345 #endif
 346         }
 347         return retval;
 348 }
 349
 350 static int do_callout(struct sysfs_class_device *class_dev, struct udevice *udev, struct sysfs_device *sysfs_device)
 351 {
 352         struct config_device *dev;
 353         struct list_head *tmp;
 354
 355         list_for_each(tmp, &config_device_list) {
 356                 dev = list_entry(tmp, struct config_device, node);
 357                 if (dev->type != CALLOUT)
 358                         continue;
 359
 360                 if (sysfs_device) {
 361                         dbg("dev->bus='%s' sysfs_device->bus='%s'", dev->bus, sysfs_device->bus);
 362                         if (strcasecmp(dev->bus, sysfs_device->bus) != 0)
 363                                 continue;
 364                 }
 365
 366                 /* substitute anything that needs to be in the program name */
 367                 apply_format(udev, dev->exec_program);
 368                 if (exec_callout(dev, udev->callout_value, NAME_SIZE))
 369                         continue;
 370                 if (strcmp_pattern(dev->id, udev->callout_value) != 0)
 371                         continue;
 372                 strfieldcpy(udev->name, dev->name);
 373                 strfieldcpy(udev->symlink, dev->symlink);
 374                 dbg("callout returned matching value '%s', '%s' becomes '%s'",
 375                     dev->id, class_dev->name, udev->name);
 376                 return 0;
 377         }
 378         return -ENODEV;
 379 }
 380
 381 static int do_label(struct sysfs_class_device *class_dev, struct udevice *udev, struct sysfs_device *sysfs_device)
 382 {
 383         struct sysfs_attribute *tmpattr = NULL;
 384         struct config_device *dev;
 385         struct list_head *tmp;
 386         char *c;
 387
 388         list_for_each(tmp, &config_device_list) {
 389                 dev = list_entry(tmp, struct config_device, node);
 390                 if (dev->type != LABEL)
 391                         continue;
 392
 393                 if (sysfs_device) {
 394                         dbg("dev->bus='%s' sysfs_device->bus='%s'", dev->bus, sysfs_device->bus);
 395                         if (strcasecmp(dev->bus, sysfs_device->bus) != 0)
 396                                 continue;
 397                 }
 398
 399                 dbg("look for device attribute '%s'", dev->sysfs_file);
 400                 /* try to find the attribute in the class device directory */
 401                 tmpattr = sysfs_get_classdev_attr(class_dev, dev->sysfs_file);
 402                 if (tmpattr)
 403                         goto label_found;
 404
 405                 /* look in the class device directory if present */
 406                 if (sysfs_device) {
 407                         tmpattr = sysfs_get_device_attr(sysfs_device, dev->sysfs_file);
 408                         if (tmpattr)
 409                                 goto label_found;
 410                 }
 411
 412                 continue;
 413
 414 label_found:
 415                 c = tmpattr->value + strlen(tmpattr->value)-1;
 416                 if (*c == '\n')
 417                         *c = 0x00;
 418                 dbg("compare attribute '%s' value '%s' with '%s'",
 419                           dev->sysfs_file, tmpattr->value, dev->sysfs_value);
 420                 if (strcmp_pattern(dev->sysfs_value, tmpattr->value) != 0)
 421                         continue;
 422
 423                 strfieldcpy(udev->name, dev->name);
 424                 strfieldcpy(udev->symlink, dev->symlink);
 425                 dbg("found matching attribute '%s', '%s' becomes '%s' ",
 426                     dev->sysfs_file, class_dev->name, udev->name);
 427
 428                 return 0;
 429         }
 430         return -ENODEV;
 431 }
 432
 433 static int do_number(struct sysfs_class_device *class_dev, struct udevice *udev, struct sysfs_device *sysfs_device)
 434 {
 435         struct config_device *dev;
 436         struct list_head *tmp;
 437         char path[SYSFS_PATH_MAX];
 438         int found;
 439         char *temp = NULL;
 440
 441         /* we have to have a sysfs device for NUMBER to work */
 442         if (!sysfs_device)
 443                 return -ENODEV;
 444
 445         list_for_each(tmp, &config_device_list) {
 446                 dev = list_entry(tmp, struct config_device, node);
 447                 if (dev->type != NUMBER)
 448                         continue;
 449
 450                 dbg("dev->bus='%s' sysfs_device->bus='%s'", dev->bus, sysfs_device->bus);
 451                 if (strcasecmp(dev->bus, sysfs_device->bus) != 0)
 452                         continue;
 453
 454                 found = 0;
 455                 strfieldcpy(path, sysfs_device->path);
 456                 temp = strrchr(path, '/');
 457                 dbg("search '%s' in '%s', path='%s'", dev->id, temp, path);
 458                 if (strstr(temp, dev->id) != NULL) {
 459                         found = 1;
 460                 } else {
 461                         *temp = 0x00;
 462                         temp = strrchr(path, '/');
 463                         dbg("search '%s' in '%s', path='%s'", dev->id, temp, path);
 464                         if (strstr(temp, dev->id) != NULL)
 465                                 found = 1;
 466                 }
 467                 if (!found)
 468                         continue;
 469                 strfieldcpy(udev->name, dev->name);
 470                 strfieldcpy(udev->symlink, dev->symlink);
 471                 dbg("found matching id '%s', '%s' becomes '%s'",
 472                     dev->id, class_dev->name, udev->name);
 473                 return 0;
 474         }
 475         return -ENODEV;
 476 }
 477
 478 static int do_topology(struct sysfs_class_device *class_dev, struct udevice *udev, struct sysfs_device *sysfs_device)
 479 {
 480         struct config_device *dev;
 481         struct list_head *tmp;
 482         char path[SYSFS_PATH_MAX];
 483         int found;
 484         char *temp = NULL;
 485
 486         /* we have to have a sysfs device for TOPOLOGY to work */
 487         if (!sysfs_device)
 488                 return -ENODEV;
 489
 490         list_for_each(tmp, &config_device_list) {
 491                 dev = list_entry(tmp, struct config_device, node);
 492                 if (dev->type != TOPOLOGY)
 493                         continue;
 494
 495                 dbg("dev->bus='%s' sysfs_device->bus='%s'", dev->bus, sysfs_device->bus);
 496                 if (strcasecmp(dev->bus, sysfs_device->bus) != 0)
 497                         continue;
 498
 499                 found = 0;
 500                 strfieldcpy(path, sysfs_device->path);
 501                 temp = strrchr(path, '/');
 502                 dbg("search '%s' in '%s', path='%s'", dev->place, temp, path);
 503                 if (strstr(temp, dev->place) != NULL) {
 504                         found = 1;
 505                 } else {
 506                         *temp = 0x00;
 507                         temp = strrchr(path, '/');
 508                         dbg("search '%s' in '%s', path='%s'", dev->place, temp, path);
 509                         if (strstr(temp, dev->place) != NULL)
 510                                 found = 1;
 511                 }
 512                 if (!found)
 513                         continue;
 514
 515                 strfieldcpy(udev->name, dev->name);
 516                 strfieldcpy(udev->symlink, dev->symlink);
 517                 dbg("found matching place '%s', '%s' becomes '%s'",
 518                     dev->place, class_dev->name, udev->name);
 519                 return 0;
 520         }
 521         return -ENODEV;
 522 }
 523
 524 static int do_replace(struct sysfs_class_device *class_dev, struct udevice *udev, struct sysfs_device *sysfs_device)
 525 {
 526         struct config_device *dev;
 527         struct list_head *tmp;
 528
 529         list_for_each(tmp, &config_device_list) {
 530                 dev = list_entry(tmp, struct config_device, node);
 531                 if (dev->type != REPLACE)
 532                         continue;
 533
 534                 dbg("compare name '%s' with '%s'", dev->kernel_name, class_dev->name);
 535                 if (strcmp_pattern(dev->kernel_name, class_dev->name) != 0)
 536                         continue;
 537
 538                 strfieldcpy(udev->name, dev->name);
 539                 strfieldcpy(udev->symlink, dev->symlink);
 540                 dbg("found name, '%s' becomes '%s'", dev->kernel_name, udev->name);
 541
 542                 return 0;
 543         }
 544         return -ENODEV;
 545 }
 546
 547 static void do_kernelname(struct sysfs_class_device *class_dev, struct udevice *udev)
 548 {
 549         /* heh, this is pretty simple... */
 550         strfieldcpy(udev->name, class_dev->name);
 551 }
 552
 553 int namedev_name_device(struct sysfs_class_device *class_dev, struct udevice *udev)
 554 {
 555         struct sysfs_device *sysfs_device = NULL;
 556         struct sysfs_class_device *class_dev_parent = NULL;
 557         int retval = 0;
 558         struct perm_device *perm;
 559
 560         udev->mode = 0;
 561
 562         /* find the sysfs_device for this class device */
 563         /* Wouldn't it really be nice if libsysfs could do this for us? */
 564         sysfs_device = sysfs_get_classdev_device(class_dev);
 565         if (sysfs_device == NULL) {
 566                 /* bah, let's go backwards up a level to see if the device is there,
 567                  * as block partitions don't point to the physical device.  Need to fix that
 568                  * up in the kernel...
 569                  */
 570                 if (strcmp(class_dev->classname, SYSFS_BLOCK_NAME) == 0) {
 571                         dbg("looking at block device");
 572                         if (isdigit(class_dev->path[strlen(class_dev->path)-1])) {
 573                                 dbg("really is a partition");
 574                                 class_dev_parent = sysfs_get_classdev_parent
 575                                                                    (class_dev);
 576                                 if (class_dev_parent == NULL) {
 577                                         dbg("sysfs_get_classdev_parent for class device '%s' failed", class_dev->name);
 578                                 } else {
 579                                         dbg("class_dev_parent->name='%s'", class_dev_parent->name);
 580                                         sysfs_device = sysfs_get_classdev_device(class_dev_parent);
 581                                 }
 582                         }
 583                 }
 584         }
 585
 586         if (sysfs_device) {
 587                 dbg("sysfs_device->path='%s'", sysfs_device->path);
 588                 dbg("sysfs_device->bus_id='%s'", sysfs_device->bus_id);
 589                 dbg("sysfs_device->bus='%s'", sysfs_device->bus);
 590                 strfieldcpy(udev->bus_id, sysfs_device->bus_id);
 591         } else {
 592                 dbg("class_dev->name = '%s'", class_dev->name);
 593         }
 594
 595         build_kernel_number(class_dev, udev);
 596
 597         /* rules are looked at in priority order */
 598         retval = do_callout(class_dev, udev, sysfs_device);
 599         if (retval == 0)
 600                 goto found;
 601
 602         retval = do_label(class_dev, udev, sysfs_device);
 603         if (retval == 0)
 604                 goto found;
 605
 606         retval = do_number(class_dev, udev, sysfs_device);
 607         if (retval == 0)
 608                 goto found;
 609
 610         retval = do_topology(class_dev, udev, sysfs_device);
 611         if (retval == 0)
 612                 goto found;
 613
 614         retval = do_replace(class_dev, udev, sysfs_device);
 615         if (retval == 0)
 616                 goto found;
 617
 618         do_kernelname(class_dev, udev);
 619         goto done;
 620
 621 found:
 622         /* substitute placeholder */
 623         apply_format(udev, udev->name);
 624         apply_format(udev, udev->symlink);
 625
 626 done:
 627         perm = find_perm(udev->name);
 628         if (perm) {
 629                 udev->mode = perm->mode;
 630                 strfieldcpy(udev->owner, perm->owner);
 631                 strfieldcpy(udev->group, perm->group);
 632         } else {
 633                 /* no matching perms found :( */
 634                 udev->mode = get_default_mode(class_dev);
 635                 udev->owner[0] = 0x00;
 636                 udev->group[0] = 0x00;
 637         }
 638         dbg("name, '%s' is going to have owner='%s', group='%s', mode = %#o",
 639             udev->name, udev->owner, udev->group, udev->mode);
 640
 641         return 0;
 642 }
 643
 644 int namedev_init(void)
 645 {
 646         int retval;
 647
 648         retval = namedev_init_rules();
 649         if (retval)
 650                 return retval;
 651
 652         retval = namedev_init_permissions();
 653         if (retval)
 654                 return retval;
 655
 656         dump_config_dev_list();
 657         dump_perm_dev_list();
 658         return retval;
 659 }