udev/udev-event.c

   1 /*
   2  * Copyright (C) 2003-2010 Kay Sievers <kay.sievers@vrfy.org>
   3  *
   4  * This program is free software: you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #include <stdlib.h>
  19 #include <stdio.h>
  20 #include <stddef.h>
  21 #include <unistd.h>
  22 #include <fcntl.h>
  23 #include <errno.h>
  24 #include <ctype.h>
  25 #include <string.h>
  26 #include <time.h>
  27 #include <net/if.h>
  28 #include <sys/ioctl.h>
  29 #include <sys/prctl.h>
  30 #include <sys/poll.h>
  31 #include <sys/epoll.h>
  32 #include <sys/wait.h>
  33 #include <sys/socket.h>
  34 #include <sys/signalfd.h>
  35 #include <linux/sockios.h>
  36
  37 #include "udev.h"
  38
  39 struct udev_event *udev_event_new(struct udev_device *dev)
  40 {
  41         struct udev *udev = udev_device_get_udev(dev);
  42         struct udev_event *event;
  43
  44         event = calloc(1, sizeof(struct udev_event));
  45         if (event == NULL)
  46                 return NULL;
  47         event->dev = dev;
  48         event->udev = udev;
  49         udev_list_init(udev, &event->run_list, false);
  50         event->fd_signal = -1;
  51         event->birth_usec = now_usec();
  52         event->timeout_usec = 60 * 1000 * 1000;
  53         dbg(event->udev, "allocated event %p\n", event);
  54         return event;
  55 }
  56
  57 void udev_event_unref(struct udev_event *event)
  58 {
  59         if (event == NULL)
  60                 return;
  61         udev_list_cleanup(&event->run_list);
  62         free(event->tmp_node);
  63         free(event->program_result);
  64         free(event->name);
  65         dbg(event->udev, "free event %p\n", event);
  66         free(event);
  67 }
  68
  69 size_t udev_event_apply_format(struct udev_event *event, const char *src, char *dest, size_t size)
  70 {
  71         struct udev_device *dev = event->dev;
  72         enum subst_type {
  73                 SUBST_UNKNOWN,
  74                 SUBST_TEMP_NODE,
  75                 SUBST_ATTR,
  76                 SUBST_ENV,
  77                 SUBST_KERNEL,
  78                 SUBST_KERNEL_NUMBER,
  79                 SUBST_DRIVER,
  80                 SUBST_DEVPATH,
  81                 SUBST_ID,
  82                 SUBST_MAJOR,
  83                 SUBST_MINOR,
  84                 SUBST_RESULT,
  85                 SUBST_PARENT,
  86                 SUBST_NAME,
  87                 SUBST_LINKS,
  88                 SUBST_ROOT,
  89                 SUBST_SYS,
  90         };
  91         static const struct subst_map {
  92                 char *name;
  93                 char fmt;
  94                 enum subst_type type;
  95         } map[] = {
  96                 { .name = "tempnode",   .fmt = 'N',     .type = SUBST_TEMP_NODE },
  97                 { .name = "attr",       .fmt = 's',     .type = SUBST_ATTR },
  98                 { .name = "sysfs",      .fmt = 's',     .type = SUBST_ATTR },
  99                 { .name = "env",        .fmt = 'E',     .type = SUBST_ENV },
 100                 { .name = "kernel",     .fmt = 'k',     .type = SUBST_KERNEL },
 101                 { .name = "number",     .fmt = 'n',     .type = SUBST_KERNEL_NUMBER },
 102                 { .name = "driver",     .fmt = 'd',     .type = SUBST_DRIVER },
 103                 { .name = "devpath",    .fmt = 'p',     .type = SUBST_DEVPATH },
 104                 { .name = "id",         .fmt = 'b',     .type = SUBST_ID },
 105                 { .name = "major",      .fmt = 'M',     .type = SUBST_MAJOR },
 106                 { .name = "minor",      .fmt = 'm',     .type = SUBST_MINOR },
 107                 { .name = "result",     .fmt = 'c',     .type = SUBST_RESULT },
 108                 { .name = "parent",     .fmt = 'P',     .type = SUBST_PARENT },
 109                 { .name = "name",       .fmt = 'D',     .type = SUBST_NAME },
 110                 { .name = "links",      .fmt = 'L',     .type = SUBST_LINKS },
 111                 { .name = "root",       .fmt = 'r',     .type = SUBST_ROOT },
 112                 { .name = "sys",        .fmt = 'S',     .type = SUBST_SYS },
 113         };
 114         const char *from;
 115         char *s;
 116         size_t l;
 117
 118         from = src;
 119         s = dest;
 120         l = size;
 121
 122         for (;;) {
 123                 enum subst_type type = SUBST_UNKNOWN;
 124                 char attrbuf[UTIL_PATH_SIZE];
 125                 char *attr = NULL;
 126
 127                 while (from[0] != '\0') {
 128                         if (from[0] == '$') {
 129                                 /* substitute named variable */
 130                                 unsigned int i;
 131
 132                                 if (from[1] == '$') {
 133                                         from++;
 134                                         goto copy;
 135                                 }
 136
 137                                 for (i = 0; i < ARRAY_SIZE(map); i++) {
 138                                         if (strncmp(&from[1], map[i].name, strlen(map[i].name)) == 0) {
 139                                                 type = map[i].type;
 140                                                 from += strlen(map[i].name)+1;
 141                                                 dbg(event->udev, "will substitute format name '%s'\n", map[i].name);
 142                                                 goto subst;
 143                                         }
 144                                 }
 145                         } else if (from[0] == '%') {
 146                                 /* substitute format char */
 147                                 unsigned int i;
 148
 149                                 if (from[1] == '%') {
 150                                         from++;
 151                                         goto copy;
 152                                 }
 153
 154                                 for (i = 0; i < ARRAY_SIZE(map); i++) {
 155                                         if (from[1] == map[i].fmt) {
 156                                                 type = map[i].type;
 157                                                 from += 2;
 158                                                 dbg(event->udev, "will substitute format char '%c'\n", map[i].fmt);
 159                                                 goto subst;
 160                                         }
 161                                 }
 162                         }
 163 copy:
 164                         /* copy char */
 165                         if (l == 0)
 166                                 goto out;
 167                         s[0] = from[0];
 168                         from++;
 169                         s++;
 170                         l--;
 171                 }
 172
 173                 goto out;
 174 subst:
 175                 /* extract possible $format{attr} */
 176                 if (from[0] == '{') {
 177                         unsigned int i;
 178
 179                         from++;
 180                         for (i = 0; from[i] != '}'; i++) {
 181                                 if (from[i] == '\0') {
 182                                         err(event->udev, "missing closing brace for format '%s'\n", src);
 183                                         goto out;
 184                                 }
 185                         }
 186                         if (i >= sizeof(attrbuf))
 187                                 goto out;
 188                         memcpy(attrbuf, from, i);
 189                         attrbuf[i] = '\0';
 190                         from += i+1;
 191                         attr = attrbuf;
 192                 } else {
 193                         attr = NULL;
 194                 }
 195
 196                 switch (type) {
 197                 case SUBST_DEVPATH:
 198                         l = util_strpcpy(&s, l, udev_device_get_devpath(dev));
 199                         dbg(event->udev, "substitute devpath '%s'\n", udev_device_get_devpath(dev));
 200                         break;
 201                 case SUBST_KERNEL:
 202                         l = util_strpcpy(&s, l, udev_device_get_sysname(dev));
 203                         dbg(event->udev, "substitute kernel name '%s'\n", udev_device_get_sysname(dev));
 204                         break;
 205                 case SUBST_KERNEL_NUMBER:
 206                         if (udev_device_get_sysnum(dev) == NULL)
 207                                 break;
 208                         l = util_strpcpy(&s, l, udev_device_get_sysnum(dev));
 209                         dbg(event->udev, "substitute kernel number '%s'\n", udev_device_get_sysnum(dev));
 210                         break;
 211                 case SUBST_ID:
 212                         if (event->dev_parent == NULL)
 213                                 break;
 214                         l = util_strpcpy(&s, l, udev_device_get_sysname(event->dev_parent));
 215                         dbg(event->udev, "substitute id '%s'\n", udev_device_get_sysname(event->dev_parent));
 216                         break;
 217                 case SUBST_DRIVER: {
 218                         const char *driver;
 219
 220                         if (event->dev_parent == NULL)
 221                                 break;
 222
 223                         driver = udev_device_get_driver(event->dev_parent);
 224                         if (driver == NULL)
 225                                 break;
 226                         l = util_strpcpy(&s, l, driver);
 227                         dbg(event->udev, "substitute driver '%s'\n", driver);
 228                         break;
 229                 }
 230                 case SUBST_MAJOR: {
 231                         char num[UTIL_PATH_SIZE];
 232
 233                         sprintf(num, "%d", major(udev_device_get_devnum(dev)));
 234                         l = util_strpcpy(&s, l, num);
 235                         dbg(event->udev, "substitute major number '%s'\n", num);
 236                         break;
 237                 }
 238                 case SUBST_MINOR: {
 239                         char num[UTIL_PATH_SIZE];
 240
 241                         sprintf(num, "%d", minor(udev_device_get_devnum(dev)));
 242                         l = util_strpcpy(&s, l, num);
 243                         dbg(event->udev, "substitute minor number '%s'\n", num);
 244                         break;
 245                 }
 246                 case SUBST_RESULT: {
 247                         char *rest;
 248                         int i;
 249
 250                         if (event->program_result == NULL)
 251                                 break;
 252                         /* get part part of the result string */
 253                         i = 0;
 254                         if (attr != NULL)
 255                                 i = strtoul(attr, &rest, 10);
 256                         if (i > 0) {
 257                                 char result[UTIL_PATH_SIZE];
 258                                 char tmp[UTIL_PATH_SIZE];
 259                                 char *cpos;
 260
 261                                 dbg(event->udev, "request part #%d of result string\n", i);
 262                                 util_strscpy(result, sizeof(result), event->program_result);
 263                                 cpos = result;
 264                                 while (--i) {
 265                                         while (cpos[0] != '\0' && !isspace(cpos[0]))
 266                                                 cpos++;
 267                                         while (isspace(cpos[0]))
 268                                                 cpos++;
 269                                 }
 270                                 if (i > 0) {
 271                                         err(event->udev, "requested part of result string not found\n");
 272                                         break;
 273                                 }
 274                                 util_strscpy(tmp, sizeof(tmp), cpos);
 275                                 /* %{2+}c copies the whole string from the second part on */
 276                                 if (rest[0] != '+') {
 277                                         cpos = strchr(tmp, ' ');
 278                                         if (cpos)
 279                                                 cpos[0] = '\0';
 280                                 }
 281                                 l = util_strpcpy(&s, l, tmp);
 282                                 dbg(event->udev, "substitute part of result string '%s'\n", tmp);
 283                         } else {
 284                                 l = util_strpcpy(&s, l, event->program_result);
 285                                 dbg(event->udev, "substitute result string '%s'\n", event->program_result);
 286                         }
 287                         break;
 288                 }
 289                 case SUBST_ATTR: {
 290                         const char *value = NULL;
 291                         char vbuf[UTIL_NAME_SIZE];
 292                         size_t len;
 293                         int count;
 294
 295                         if (attr == NULL) {
 296                                 err(event->udev, "missing file parameter for attr\n");
 297                                 break;
 298                         }
 299
 300                         /* try to read the value specified by "[dmi/id]product_name" */
 301                         if (util_resolve_subsys_kernel(event->udev, attr, vbuf, sizeof(vbuf), 1) == 0)
 302                                 value = vbuf;
 303
 304                         /* try to read the attribute the device */
 305                         if (value == NULL)
 306                                 value = udev_device_get_sysattr_value(event->dev, attr);
 307
 308                         /* try to read the attribute of the parent device, other matches have selected */
 309                         if (value == NULL && event->dev_parent != NULL && event->dev_parent != event->dev)
 310                                 value = udev_device_get_sysattr_value(event->dev_parent, attr);
 311
 312                         if (value == NULL)
 313                                 break;
 314
 315                         /* strip trailing whitespace, and replace unwanted characters */
 316                         if (value != vbuf)
 317                                 util_strscpy(vbuf, sizeof(vbuf), value);
 318                         len = strlen(vbuf);
 319                         while (len > 0 && isspace(vbuf[--len]))
 320                                 vbuf[len] = '\0';
 321                         count = udev_util_replace_chars(vbuf, UDEV_ALLOWED_CHARS_INPUT);
 322                         if (count > 0)
 323                                 info(event->udev, "%i character(s) replaced\n" , count);
 324                         l = util_strpcpy(&s, l, vbuf);
 325                         dbg(event->udev, "substitute sysfs value '%s'\n", vbuf);
 326                         break;
 327                 }
 328                 case SUBST_PARENT: {
 329                         struct udev_device *dev_parent;
 330                         const char *devnode;
 331
 332                         dev_parent = udev_device_get_parent(event->dev);
 333                         if (dev_parent == NULL)
 334                                 break;
 335                                 devnode = udev_device_get_devnode(dev_parent);
 336                         if (devnode != NULL) {
 337                                 size_t devlen = strlen(udev_get_dev_path(event->udev))+1;
 338
 339                                 l = util_strpcpy(&s, l, &devnode[devlen]);
 340                                 dbg(event->udev, "found parent '%s', got node name '%s'\n",
 341                                     udev_device_get_syspath(dev_parent), &devnode[devlen]);
 342                         }
 343                         break;
 344                 }
 345                 case SUBST_TEMP_NODE: {
 346                         dev_t devnum;
 347                         struct stat statbuf;
 348                         char filename[UTIL_PATH_SIZE];
 349                         const char *devtype;
 350
 351                         if (event->tmp_node != NULL) {
 352                                 l = util_strpcpy(&s, l, event->tmp_node);
 353                                 dbg(event->udev, "tempnode: return earlier created one\n");
 354                                 break;
 355                         }
 356                         devnum = udev_device_get_devnum(dev);
 357                         if (major(devnum) == 0)
 358                                 break;
 359                         /* lookup kernel provided node */
 360                         if (udev_device_get_knodename(dev) != NULL) {
 361                                 util_strscpyl(filename, sizeof(filename),
 362                                               udev_get_dev_path(event->udev), "/", udev_device_get_knodename(dev), NULL);
 363                                 if (stat(filename, &statbuf) == 0 && statbuf.st_rdev == devnum) {
 364                                         l = util_strpcpy(&s, l, filename);
 365                                         dbg(event->udev, "tempnode: return kernel node\n");
 366                                         break;
 367                                 }
 368                         }
 369                         /* lookup /dev/{char,block}/<maj>:<min> */
 370                         if (strcmp(udev_device_get_subsystem(dev), "block") == 0)
 371                                 devtype = "block";
 372                         else
 373                                 devtype = "char";
 374                         snprintf(filename, sizeof(filename), "%s/%s/%u:%u",
 375                                  udev_get_dev_path(event->udev), devtype,
 376                                  major(udev_device_get_devnum(dev)),
 377                                  minor(udev_device_get_devnum(dev)));
 378                         if (stat(filename, &statbuf) == 0 && statbuf.st_rdev == devnum) {
 379                                 l = util_strpcpy(&s, l, filename);
 380                                 dbg(event->udev, "tempnode: return maj:min node\n");
 381                                 break;
 382                         }
 383                         /* create temporary node */
 384                         dbg(event->udev, "tempnode: create temp node\n");
 385                         asprintf(&event->tmp_node, "%s/.tmp-%s-%u:%u",
 386                                  udev_get_dev_path(event->udev), devtype,
 387                                  major(udev_device_get_devnum(dev)),
 388                                  minor(udev_device_get_devnum(dev)));
 389                         if (event->tmp_node == NULL)
 390                                 break;
 391                         udev_node_mknod(dev, event->tmp_node, 0600, 0, 0);
 392                         l = util_strpcpy(&s, l, event->tmp_node);
 393                         break;
 394                 }
 395                 case SUBST_NAME:
 396                         if (event->name != NULL) {
 397                                 l = util_strpcpy(&s, l, event->name);
 398                                 dbg(event->udev, "substitute name '%s'\n", event->name);
 399                         } else {
 400                                 l = util_strpcpy(&s, l, udev_device_get_sysname(dev));
 401                                 dbg(event->udev, "substitute sysname '%s'\n", udev_device_get_sysname(dev));
 402                         }
 403                         break;
 404                 case SUBST_LINKS: {
 405                         size_t devlen = strlen(udev_get_dev_path(event->udev))+1;
 406                         struct udev_list_entry *list_entry;
 407
 408                         list_entry = udev_device_get_devlinks_list_entry(dev);
 409                         if (list_entry == NULL)
 410                                 break;
 411                         l = util_strpcpy(&s, l, &udev_list_entry_get_name(list_entry)[devlen]);
 412                         udev_list_entry_foreach(list_entry, udev_list_entry_get_next(list_entry))
 413                                 l = util_strpcpyl(&s, l, " ", &udev_list_entry_get_name(list_entry)[devlen], NULL);
 414                         break;
 415                 }
 416                 case SUBST_ROOT:
 417                         l = util_strpcpy(&s, l, udev_get_dev_path(event->udev));
 418                         dbg(event->udev, "substitute udev_root '%s'\n", udev_get_dev_path(event->udev));
 419                         break;
 420                 case SUBST_SYS:
 421                         l = util_strpcpy(&s, l, udev_get_sys_path(event->udev));
 422                         dbg(event->udev, "substitute sys_path '%s'\n", udev_get_sys_path(event->udev));
 423                         break;
 424                 case SUBST_ENV:
 425                         if (attr == NULL) {
 426                                 dbg(event->udev, "missing attribute\n");
 427                                 break;
 428                         } else {
 429                                 const char *value;
 430
 431                                 value = udev_device_get_property_value(event->dev, attr);
 432                                 if (value == NULL)
 433                                         break;
 434                                 dbg(event->udev, "substitute env '%s=%s'\n", attr, value);
 435                                 l = util_strpcpy(&s, l, value);
 436                                 break;
 437                         }
 438                 default:
 439                         err(event->udev, "unknown substitution type=%i\n", type);
 440                         break;
 441                 }
 442         }
 443
 444 out:
 445         s[0] = '\0';
 446         dbg(event->udev, "'%s' -> '%s' (%zu)\n", src, dest, l);
 447         return l;
 448 }
 449
 450 static int spawn_exec(struct udev_event *event,
 451                       const char *cmd, char *const argv[], char **envp, const sigset_t *sigmask,
 452                       int fd_stdout, int fd_stderr)
 453 {
 454         struct udev *udev = event->udev;
 455         int err;
 456         int fd;
 457
 458         /* discard child output or connect to pipe */
 459         fd = open("/dev/null", O_RDWR);
 460         if (fd >= 0) {
 461                 dup2(fd, STDIN_FILENO);
 462                 if (fd_stdout < 0)
 463                         dup2(fd, STDOUT_FILENO);
 464                 if (fd_stderr < 0)
 465                         dup2(fd, STDERR_FILENO);
 466                 close(fd);
 467         } else {
 468                 err(udev, "open /dev/null failed: %m\n");
 469         }
 470
 471         /* connect pipes to std{out,err} */
 472         if (fd_stdout >= 0) {
 473                 dup2(fd_stdout, STDOUT_FILENO);
 474                         close(fd_stdout);
 475         }
 476         if (fd_stderr >= 0) {
 477                 dup2(fd_stderr, STDERR_FILENO);
 478                 close(fd_stderr);
 479         }
 480
 481         /* terminate child in case parent goes away */
 482         prctl(PR_SET_PDEATHSIG, SIGTERM);
 483
 484         /* restore original udev sigmask before exec */
 485         if (sigmask)
 486                 sigprocmask(SIG_SETMASK, sigmask, NULL);
 487
 488         execve(argv[0], argv, envp);
 489
 490         /* exec failed */
 491         err = -errno;
 492         err(udev, "failed to execute '%s' '%s': %m\n", argv[0], cmd);
 493         return err;
 494 }
 495
 496 static int spawn_read(struct udev_event *event,
 497                       const char *cmd,
 498                       int fd_stdout, int fd_stderr,
 499                       char *result, size_t ressize)
 500 {
 501         struct udev *udev = event->udev;
 502         size_t respos = 0;
 503         int fd_ep = -1;
 504         struct epoll_event ep_outpipe, ep_errpipe;
 505         int err = 0;
 506
 507         /* read from child if requested */
 508         if (fd_stdout < 0 && fd_stderr < 0)
 509                 return 0;
 510
 511         fd_ep = epoll_create1(EPOLL_CLOEXEC);
 512         if (fd_ep < 0) {
 513                 err = -errno;
 514                 err(udev, "error creating epoll fd: %m\n");
 515                 goto out;
 516         }
 517
 518         if (fd_stdout >= 0) {
 519                 memset(&ep_outpipe, 0, sizeof(struct epoll_event));
 520                 ep_outpipe.events = EPOLLIN;
 521                 ep_outpipe.data.ptr = &fd_stdout;
 522                 if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_stdout, &ep_outpipe) < 0) {
 523                         err(udev, "fail to add fd to epoll: %m\n");
 524                         goto out;
 525                 }
 526         }
 527
 528         if (fd_stderr >= 0) {
 529                 memset(&ep_errpipe, 0, sizeof(struct epoll_event));
 530                 ep_errpipe.events = EPOLLIN;
 531                 ep_errpipe.data.ptr = &fd_stderr;
 532                 if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_stderr, &ep_errpipe) < 0) {
 533                         err(udev, "fail to add fd to epoll: %m\n");
 534                         goto out;
 535                 }
 536         }
 537
 538         /* read child output */
 539         while (fd_stdout >= 0 || fd_stderr >= 0) {
 540                 int timeout;
 541                 int fdcount;
 542                 struct epoll_event ev[4];
 543                 int i;
 544
 545                 if (event->timeout_usec > 0) {
 546                         unsigned long long age_usec;
 547
 548                         age_usec = now_usec() - event->birth_usec;
 549                         if (age_usec >= event->timeout_usec) {
 550                                 err = -ETIMEDOUT;
 551                                 err(udev, "timeout '%s'\n", cmd);
 552                                 goto out;
 553                         }
 554                         timeout = ((event->timeout_usec - age_usec) / 1000) + 1000;
 555                 } else {
 556                         timeout = -1;
 557                 }
 558
 559                 fdcount = epoll_wait(fd_ep, ev, ARRAY_SIZE(ev), timeout);
 560                 if (fdcount < 0) {
 561                         if (errno == EINTR)
 562                                 continue;
 563                         err = -errno;
 564                         err(udev, "failed to poll: %m\n");
 565                         goto out;
 566                 }
 567                 if (fdcount == 0) {
 568                         err  = -ETIMEDOUT;
 569                         err(udev, "timeout '%s'\n", cmd);
 570                         goto out;
 571                 }
 572
 573                 for (i = 0; i < fdcount; i++) {
 574                         int *fd = (int *)ev[i].data.ptr;
 575
 576                         if (ev[i].events & EPOLLIN) {
 577                                 ssize_t count;
 578                                 char buf[4096];
 579
 580                                 count = read(*fd, buf, sizeof(buf)-1);
 581                                 if (count <= 0)
 582                                         continue;
 583                                 buf[count] = '\0';
 584
 585                                 /* store stdout result */
 586                                 if (result != NULL && *fd == fd_stdout) {
 587                                         if (respos + count < ressize) {
 588                                                 memcpy(&result[respos], buf, count);
 589                                                 respos += count;
 590                                         } else {
 591                                                 err(udev, "'%s' ressize %zd too short\n", cmd, ressize);
 592                                                 err = -ENOBUFS;
 593                                         }
 594                                 }
 595
 596                                 /* log debug output only if we watch stderr */
 597                                 if (fd_stderr >= 0) {
 598                                         char *pos;
 599                                         char *line;
 600
 601                                         pos = buf;
 602                                         while ((line = strsep(&pos, "\n"))) {
 603                                                 if (pos != NULL || line[0] != '\0')
 604                                                         info(udev, "'%s'(%s) '%s'\n", cmd, *fd == fd_stdout ? "out" : "err" , line);
 605                                         }
 606                                 }
 607                         } else if (ev[i].events & EPOLLHUP) {
 608                                 if (epoll_ctl(fd_ep, EPOLL_CTL_DEL, *fd, NULL) < 0) {
 609                                         err = -errno;
 610                                         err(udev, "failed to remove fd from epoll: %m\n");
 611                                         goto out;
 612                                 }
 613                                 *fd = -1;
 614                         }
 615                 }
 616         }
 617
 618         /* return the child's stdout string */
 619         if (result != NULL) {
 620                 result[respos] = '\0';
 621                 dbg(udev, "result='%s'\n", result);
 622         }
 623 out:
 624         if (fd_ep >= 0)
 625                 close(fd_ep);
 626         return err;
 627 }
 628
 629 static int spawn_wait(struct udev_event *event, const char *cmd, pid_t pid)
 630 {
 631         struct udev *udev = event->udev;
 632         struct pollfd pfd[1];
 633         int err = 0;
 634
 635         pfd[0].events = POLLIN;
 636         pfd[0].fd = event->fd_signal;
 637
 638         while (pid > 0) {
 639                 int timeout;
 640                 int fdcount;
 641
 642                 if (event->timeout_usec > 0) {
 643                         unsigned long long age_usec;
 644
 645                         age_usec = now_usec() - event->birth_usec;
 646                         if (age_usec >= event->timeout_usec)
 647                                 timeout = 1000;
 648                         else
 649                                 timeout = ((event->timeout_usec - age_usec) / 1000) + 1000;
 650                 } else {
 651                         timeout = -1;
 652                 }
 653
 654                 fdcount = poll(pfd, 1, timeout);
 655                 if (fdcount < 0) {
 656                         if (errno == EINTR)
 657                                 continue;
 658                         err = -errno;
 659                         err(udev, "failed to poll: %m\n");
 660                         goto out;
 661                 }
 662                 if (fdcount == 0) {
 663                         err(udev, "timeout: killing '%s' [%u]\n", cmd, pid);
 664                         kill(pid, SIGKILL);
 665                 }
 666
 667                 if (pfd[0].revents & POLLIN) {
 668                         struct signalfd_siginfo fdsi;
 669                         int status;
 670                         ssize_t size;
 671
 672                         size = read(event->fd_signal, &fdsi, sizeof(struct signalfd_siginfo));
 673                         if (size != sizeof(struct signalfd_siginfo))
 674                                 continue;
 675
 676                         switch (fdsi.ssi_signo) {
 677                         case SIGTERM:
 678                                 event->sigterm = true;
 679                                 break;
 680                         case SIGCHLD:
 681                                 if (waitpid(pid, &status, WNOHANG) < 0)
 682                                         break;
 683                                 if (WIFEXITED(status)) {
 684                                         info(udev, "'%s' [%u] exit with return code %i\n", cmd, pid, WEXITSTATUS(status));
 685                                         if (WEXITSTATUS(status) != 0)
 686                                                 err = -1;
 687                                 } else if (WIFSIGNALED(status)) {
 688                                         err(udev, "'%s' [%u] terminated by signal %i (%s)\n", cmd, pid, WTERMSIG(status), strsignal(WTERMSIG(status)));
 689                                         err = -1;
 690                                 } else if (WIFSTOPPED(status)) {
 691                                         err(udev, "'%s' [%u] stopped\n", cmd, pid);
 692                                         err = -1;
 693                                 } else if (WIFCONTINUED(status)) {
 694                                         err(udev, "'%s' [%u] continued\n", cmd, pid);
 695                                         err = -1;
 696                                 } else {
 697                                         err(udev, "'%s' [%u] exit with status 0x%04x\n", cmd, pid, status);
 698                                         err = -1;
 699                                 }
 700                                 pid = 0;
 701                                 break;
 702                         }
 703                 }
 704         }
 705 out:
 706         return err;
 707 }
 708
 709 int udev_event_spawn(struct udev_event *event,
 710                      const char *cmd, char **envp, const sigset_t *sigmask,
 711                      char *result, size_t ressize)
 712 {
 713         struct udev *udev = event->udev;
 714         int outpipe[2] = {-1, -1};
 715         int errpipe[2] = {-1, -1};
 716         pid_t pid;
 717         char arg[UTIL_PATH_SIZE];
 718         char program[UTIL_PATH_SIZE];
 719         char *argv[((sizeof(arg) + 1) / 2) + 1];
 720         int i;
 721         int err = 0;
 722
 723         /* build argv from command */
 724         util_strscpy(arg, sizeof(arg), cmd);
 725         i = 0;
 726         if (strchr(arg, ' ') != NULL) {
 727                 char *pos = arg;
 728
 729                 while (pos != NULL && pos[0] != '\0') {
 730                         if (pos[0] == '\'') {
 731                                 /* do not separate quotes */
 732                                 pos++;
 733                                 argv[i] = strsep(&pos, "\'");
 734                                 if (pos != NULL)
 735                                         while (pos[0] == ' ')
 736                                                 pos++;
 737                         } else {
 738                                 argv[i] = strsep(&pos, " ");
 739                                 if (pos != NULL)
 740                                         while (pos[0] == ' ')
 741                                                 pos++;
 742                         }
 743                         dbg(udev, "arg[%i] '%s'\n", i, argv[i]);
 744                         i++;
 745                 }
 746                 argv[i] = NULL;
 747         } else {
 748                 argv[0] = arg;
 749                 argv[1] = NULL;
 750         }
 751
 752         /* pipes from child to parent */
 753         if (result != NULL || udev_get_log_priority(udev) >= LOG_INFO) {
 754                 if (pipe2(outpipe, O_NONBLOCK) != 0) {
 755                         err = -errno;
 756                         err(udev, "pipe failed: %m\n");
 757                         goto out;
 758                 }
 759         }
 760         if (udev_get_log_priority(udev) >= LOG_INFO) {
 761                 if (pipe2(errpipe, O_NONBLOCK) != 0) {
 762                         err = -errno;
 763                         err(udev, "pipe failed: %m\n");
 764                         goto out;
 765                 }
 766         }
 767
 768         /* allow programs in /lib/udev/ to be called without the path */
 769         if (argv[0][0] != '/') {
 770                 util_strscpyl(program, sizeof(program), LIBEXECDIR "/", argv[0], NULL);
 771                 argv[0] = program;
 772         }
 773
 774         pid = fork();
 775         switch(pid) {
 776         case 0:
 777                 /* child closes parent's ends of pipes */
 778                 if (outpipe[READ_END] >= 0) {
 779                         close(outpipe[READ_END]);
 780                         outpipe[READ_END] = -1;
 781                 }
 782                 if (errpipe[READ_END] >= 0) {
 783                         close(errpipe[READ_END]);
 784                         errpipe[READ_END] = -1;
 785                 }
 786
 787                 info(udev, "starting '%s'\n", cmd);
 788
 789                 err = spawn_exec(event, cmd, argv, envp, sigmask,
 790                                  outpipe[WRITE_END], errpipe[WRITE_END]);
 791
 792                 _exit(2 );
 793         case -1:
 794                 err(udev, "fork of '%s' failed: %m\n", cmd);
 795                 err = -1;
 796                 goto out;
 797         default:
 798                 /* parent closed child's ends of pipes */
 799                 if (outpipe[WRITE_END] >= 0) {
 800                         close(outpipe[WRITE_END]);
 801                         outpipe[WRITE_END] = -1;
 802                 }
 803                 if (errpipe[WRITE_END] >= 0) {
 804                         close(errpipe[WRITE_END]);
 805                         errpipe[WRITE_END] = -1;
 806                 }
 807
 808                 err = spawn_read(event, cmd,
 809                                  outpipe[READ_END], errpipe[READ_END],
 810                                  result, ressize);
 811
 812                 err = spawn_wait(event, cmd, pid);
 813         }
 814
 815 out:
 816         if (outpipe[READ_END] >= 0)
 817                 close(outpipe[READ_END]);
 818         if (outpipe[WRITE_END] >= 0)
 819                 close(outpipe[WRITE_END]);
 820         if (errpipe[READ_END] >= 0)
 821                 close(errpipe[READ_END]);
 822         if (errpipe[WRITE_END] >= 0)
 823                 close(errpipe[WRITE_END]);
 824         return err;
 825 }
 826
 827 static void rename_netif_kernel_log(struct ifreq ifr)
 828 {
 829         int klog;
 830         FILE *f;
 831
 832         klog = open("/dev/kmsg", O_WRONLY);
 833         if (klog < 0)
 834                 return;
 835
 836         f = fdopen(klog, "w");
 837         if (f == NULL) {
 838                 close(klog);
 839                 return;
 840         }
 841
 842         fprintf(f, "<30>udevd[%u]: renamed network interface %s to %s\n",
 843                 getpid(), ifr.ifr_name, ifr.ifr_newname);
 844         fclose(f);
 845 }
 846
 847 static int rename_netif(struct udev_event *event)
 848 {
 849         struct udev_device *dev = event->dev;
 850         int sk;
 851         struct ifreq ifr;
 852         int loop;
 853         int err;
 854
 855         info(event->udev, "changing net interface name from '%s' to '%s'\n",
 856              udev_device_get_sysname(dev), event->name);
 857
 858         sk = socket(PF_INET, SOCK_DGRAM, 0);
 859         if (sk < 0) {
 860                 err = -errno;
 861                 err(event->udev, "error opening socket: %m\n");
 862                 return err;
 863         }
 864
 865         memset(&ifr, 0x00, sizeof(struct ifreq));
 866         util_strscpy(ifr.ifr_name, IFNAMSIZ, udev_device_get_sysname(dev));
 867         util_strscpy(ifr.ifr_newname, IFNAMSIZ, event->name);
 868         err = ioctl(sk, SIOCSIFNAME, &ifr);
 869         if (err == 0) {
 870                 rename_netif_kernel_log(ifr);
 871                 goto out;
 872         }
 873
 874         /* keep trying if the destination interface name already exists */
 875         err = -errno;
 876         if (err != -EEXIST)
 877                 goto out;
 878
 879         /* free our own name, another process may wait for us */
 880         snprintf(ifr.ifr_newname, IFNAMSIZ, "rename%u", udev_device_get_ifindex(dev));
 881         err = ioctl(sk, SIOCSIFNAME, &ifr);
 882         if (err < 0) {
 883                 err = -errno;
 884                 goto out;
 885         }
 886
 887         /* log temporary name */
 888         rename_netif_kernel_log(ifr);
 889
 890         /* wait a maximum of 90 seconds for our target to become available */
 891         util_strscpy(ifr.ifr_name, IFNAMSIZ, ifr.ifr_newname);
 892         util_strscpy(ifr.ifr_newname, IFNAMSIZ, event->name);
 893         loop = 90 * 20;
 894         while (loop--) {
 895                 const struct timespec duration = { 0, 1000 * 1000 * 1000 / 20 };
 896
 897                 dbg(event->udev, "wait for netif '%s' to become free, loop=%i\n",
 898                     event->name, (90 * 20) - loop);
 899                 nanosleep(&duration, NULL);
 900
 901                 err = ioctl(sk, SIOCSIFNAME, &ifr);
 902                 if (err == 0) {
 903                         rename_netif_kernel_log(ifr);
 904                         break;
 905                 }
 906                 err = -errno;
 907                 if (err != -EEXIST)
 908                         break;
 909         }
 910
 911 out:
 912         if (err < 0)
 913                 err(event->udev, "error changing net interface name %s to %s: %m\n", ifr.ifr_name, ifr.ifr_newname);
 914         close(sk);
 915         return err;
 916 }
 917
 918 int udev_event_execute_rules(struct udev_event *event, struct udev_rules *rules, const sigset_t *sigmask)
 919 {
 920         struct udev_device *dev = event->dev;
 921         int err = 0;
 922
 923         if (udev_device_get_subsystem(dev) == NULL)
 924                 return -1;
 925
 926         if (strcmp(udev_device_get_action(dev), "remove") == 0) {
 927                 udev_device_read_db(dev, NULL);
 928                 udev_device_delete_db(dev);
 929                 udev_device_tag_index(dev, NULL, false);
 930
 931                 if (major(udev_device_get_devnum(dev)) != 0)
 932                         udev_watch_end(event->udev, dev);
 933
 934                 udev_rules_apply_to_event(rules, event, sigmask);
 935
 936                 if (major(udev_device_get_devnum(dev)) != 0)
 937                         err = udev_node_remove(dev);
 938         } else {
 939                 event->dev_db = udev_device_new_from_syspath(event->udev, udev_device_get_syspath(dev));
 940                 if (event->dev_db != NULL) {
 941                         udev_device_read_db(event->dev_db, NULL);
 942                         udev_device_set_info_loaded(event->dev_db);
 943
 944                         /* disable watch during event processing */
 945                         if (major(udev_device_get_devnum(dev)) != 0)
 946                                 udev_watch_end(event->udev, event->dev_db);
 947                 }
 948
 949                 udev_rules_apply_to_event(rules, event, sigmask);
 950
 951                 /* rename a new network interface, if needed */
 952                 if (udev_device_get_ifindex(dev) > 0 && strcmp(udev_device_get_action(dev), "add") == 0 &&
 953                     event->name != NULL && strcmp(event->name, udev_device_get_sysname(dev)) != 0) {
 954                         char syspath[UTIL_PATH_SIZE];
 955                         char *pos;
 956
 957                         err = rename_netif(event);
 958                         if (err == 0) {
 959                                 info(event->udev, "renamed netif to '%s'\n", event->name);
 960
 961                                 /* remember old name */
 962                                 udev_device_add_property(dev, "INTERFACE_OLD", udev_device_get_sysname(dev));
 963
 964                                 /* now change the devpath, because the kernel device name has changed */
 965                                 util_strscpy(syspath, sizeof(syspath), udev_device_get_syspath(dev));
 966                                 pos = strrchr(syspath, '/');
 967                                 if (pos != NULL) {
 968                                         pos++;
 969                                         util_strscpy(pos, sizeof(syspath) - (pos - syspath), event->name);
 970                                         udev_device_set_syspath(event->dev, syspath);
 971                                         udev_device_add_property(dev, "INTERFACE", udev_device_get_sysname(dev));
 972                                         info(event->udev, "changed devpath to '%s'\n", udev_device_get_devpath(dev));
 973                                 }
 974                         }
 975                 }
 976
 977                 if (major(udev_device_get_devnum(dev)) != 0) {
 978                         char filename[UTIL_PATH_SIZE];
 979
 980                         if (event->tmp_node != NULL) {
 981                                 info(event->udev, "cleanup temporary device node\n");
 982                                 util_unlink_secure(event->udev, event->tmp_node);
 983                                 free(event->tmp_node);
 984                                 event->tmp_node = NULL;
 985                         }
 986
 987                         /* no rule, use kernel provided name */
 988                         if (event->name == NULL) {
 989                                 if (udev_device_get_knodename(dev) != NULL) {
 990                                         event->name = strdup(udev_device_get_knodename(dev));
 991                                         info(event->udev, "no node name set, will use kernel supplied name '%s'\n", event->name);
 992                                 } else {
 993                                         event->name = strdup(udev_device_get_sysname(event->dev));
 994                                         info(event->udev, "no node name set, will use device name '%s'\n", event->name);
 995                                 }
 996                         }
 997
 998                         if (event->name == NULL || event->name[0] == '\0') {
 999                                 udev_device_delete_db(dev);
1000                                 udev_device_tag_index(dev, NULL, false);
1001                                 udev_device_unref(event->dev_db);
1002                                 err = -ENOMEM;
1003                                 err(event->udev, "no node name, something went wrong, ignoring\n");
1004                                 goto out;
1005                         }
1006
1007                         if (udev_device_get_knodename(dev) != NULL && strcmp(udev_device_get_knodename(dev), event->name) != 0)
1008                                 err(event->udev, "kernel-provided name '%s' and NAME= '%s' disagree, "
1009                                     "please use SYMLINK+= or change the kernel to provide the proper name\n",
1010                                     udev_device_get_knodename(dev), event->name);
1011
1012                         /* set device node name */
1013                         util_strscpyl(filename, sizeof(filename), udev_get_dev_path(event->udev), "/", event->name, NULL);
1014                         udev_device_set_devnode(dev, filename);
1015
1016                         /* remove/update possible left-over symlinks from old database entry */
1017                         if (event->dev_db != NULL)
1018                                 udev_node_update_old_links(dev, event->dev_db);
1019
1020                         if (!event->mode_set) {
1021                                 if (udev_device_get_devnode_mode(dev) > 0) {
1022                                         /* kernel supplied value */
1023                                         event->mode = udev_device_get_devnode_mode(dev);
1024                                 } else if (event->gid > 0) {
1025                                         /* default 0660 if a group is assigned */
1026                                         event->mode = 0660;
1027                                 } else {
1028                                         /* default 0600 */
1029                                         event->mode = 0600;
1030                                 }
1031                         }
1032
1033                         /* set sticky bit, so we do not remove the node on module unload */
1034                         if (event->static_node)
1035                                 event->mode |= 01000;
1036
1037                         err = udev_node_add(dev, event->mode, event->uid, event->gid);
1038                 }
1039
1040                 /* preserve old, or get new initialization timestamp */
1041                 if (event->dev_db != NULL && udev_device_get_usec_initialized(event->dev_db) > 0)
1042                         udev_device_set_usec_initialized(event->dev, udev_device_get_usec_initialized(event->dev_db));
1043                 else
1044                         udev_device_set_usec_initialized(event->dev, now_usec());
1045
1046                 /* (re)write database file */
1047                 udev_device_update_db(dev);
1048                 udev_device_tag_index(dev, event->dev_db, true);
1049                 udev_device_set_is_initialized(dev);
1050
1051                 udev_device_unref(event->dev_db);
1052                 event->dev_db = NULL;
1053         }
1054 out:
1055         return err;
1056 }
1057
1058 int udev_event_execute_run(struct udev_event *event, const sigset_t *sigmask)
1059 {
1060         struct udev_list_entry *list_entry;
1061         int err = 0;
1062
1063         dbg(event->udev, "executing run list\n");
1064         udev_list_entry_foreach(list_entry, udev_list_get_entry(&event->run_list)) {
1065                 const char *cmd = udev_list_entry_get_name(list_entry);
1066
1067                 if (strncmp(cmd, "socket:", strlen("socket:")) == 0) {
1068                         struct udev_monitor *monitor;
1069
1070                         monitor = udev_monitor_new_from_socket(event->udev, &cmd[strlen("socket:")]);
1071                         if (monitor == NULL)
1072                                 continue;
1073                         udev_monitor_send_device(monitor, NULL, event->dev);
1074                         udev_monitor_unref(monitor);
1075                 } else {
1076                         char program[UTIL_PATH_SIZE];
1077                         char **envp;
1078
1079                         if (event->exec_delay > 0) {
1080                                 info(event->udev, "delay execution of '%s'\n", program);
1081                                 sleep(event->exec_delay);
1082                         }
1083
1084                         udev_event_apply_format(event, cmd, program, sizeof(program));
1085                         envp = udev_device_get_properties_envp(event->dev);
1086                         if (udev_event_spawn(event, program, envp, sigmask, NULL, 0) < 0) {
1087                                 if (udev_list_entry_get_num(list_entry))
1088                                         err = -1;
1089                         }
1090                 }
1091         }
1092         return err;
1093 }