src/udev/udev-event.c

   1 /*
   2  * Copyright (C) 2003-2013 Kay Sievers <kay@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/prctl.h>
  29 #include <sys/poll.h>
  30 #include <sys/epoll.h>
  31 #include <sys/wait.h>
  32 #include <sys/signalfd.h>
  33
  34 #include "udev.h"
  35 #include "rtnl-util.h"
  36
  37 struct udev_event *udev_event_new(struct udev_device *dev) {
  38         struct udev *udev = udev_device_get_udev(dev);
  39         struct udev_event *event;
  40
  41         event = new0(struct udev_event, 1);
  42         if (event == NULL)
  43                 return NULL;
  44         event->dev = dev;
  45         event->udev = udev;
  46         udev_list_init(udev, &event->run_list, false);
  47         udev_list_init(udev, &event->seclabel_list, false);
  48         event->fd_signal = -1;
  49         event->birth_usec = now(CLOCK_MONOTONIC);
  50         return event;
  51 }
  52
  53 void udev_event_unref(struct udev_event *event) {
  54         if (event == NULL)
  55                 return;
  56         udev_list_cleanup(&event->run_list);
  57         udev_list_cleanup(&event->seclabel_list);
  58         free(event->program_result);
  59         free(event->name);
  60         free(event);
  61 }
  62
  63 size_t udev_event_apply_format(struct udev_event *event, const char *src, char *dest, size_t size) {
  64         struct udev_device *dev = event->dev;
  65         enum subst_type {
  66                 SUBST_UNKNOWN,
  67                 SUBST_DEVNODE,
  68                 SUBST_ATTR,
  69                 SUBST_ENV,
  70                 SUBST_KERNEL,
  71                 SUBST_KERNEL_NUMBER,
  72                 SUBST_DRIVER,
  73                 SUBST_DEVPATH,
  74                 SUBST_ID,
  75                 SUBST_MAJOR,
  76                 SUBST_MINOR,
  77                 SUBST_RESULT,
  78                 SUBST_PARENT,
  79                 SUBST_NAME,
  80                 SUBST_LINKS,
  81                 SUBST_ROOT,
  82                 SUBST_SYS,
  83         };
  84         static const struct subst_map {
  85                 const char *name;
  86                 const char fmt;
  87                 enum subst_type type;
  88         } map[] = {
  89                 { .name = "devnode",  .fmt = 'N', .type = SUBST_DEVNODE },
  90                 { .name = "tempnode", .fmt = 'N', .type = SUBST_DEVNODE },
  91                 { .name = "attr",     .fmt = 's', .type = SUBST_ATTR },
  92                 { .name = "sysfs",    .fmt = 's', .type = SUBST_ATTR },
  93                 { .name = "env",      .fmt = 'E', .type = SUBST_ENV },
  94                 { .name = "kernel",   .fmt = 'k', .type = SUBST_KERNEL },
  95                 { .name = "number",   .fmt = 'n', .type = SUBST_KERNEL_NUMBER },
  96                 { .name = "driver",   .fmt = 'd', .type = SUBST_DRIVER },
  97                 { .name = "devpath",  .fmt = 'p', .type = SUBST_DEVPATH },
  98                 { .name = "id",       .fmt = 'b', .type = SUBST_ID },
  99                 { .name = "major",    .fmt = 'M', .type = SUBST_MAJOR },
 100                 { .name = "minor",    .fmt = 'm', .type = SUBST_MINOR },
 101                 { .name = "result",   .fmt = 'c', .type = SUBST_RESULT },
 102                 { .name = "parent",   .fmt = 'P', .type = SUBST_PARENT },
 103                 { .name = "name",     .fmt = 'D', .type = SUBST_NAME },
 104                 { .name = "links",    .fmt = 'L', .type = SUBST_LINKS },
 105                 { .name = "root",     .fmt = 'r', .type = SUBST_ROOT },
 106                 { .name = "sys",      .fmt = 'S', .type = SUBST_SYS },
 107         };
 108         const char *from;
 109         char *s;
 110         size_t l;
 111
 112         from = src;
 113         s = dest;
 114         l = size;
 115
 116         for (;;) {
 117                 enum subst_type type = SUBST_UNKNOWN;
 118                 char attrbuf[UTIL_PATH_SIZE];
 119                 char *attr = NULL;
 120
 121                 while (from[0] != '\0') {
 122                         if (from[0] == '$') {
 123                                 /* substitute named variable */
 124                                 unsigned int i;
 125
 126                                 if (from[1] == '$') {
 127                                         from++;
 128                                         goto copy;
 129                                 }
 130
 131                                 for (i = 0; i < ELEMENTSOF(map); i++) {
 132                                         if (startswith(&from[1], map[i].name)) {
 133                                                 type = map[i].type;
 134                                                 from += strlen(map[i].name)+1;
 135                                                 goto subst;
 136                                         }
 137                                 }
 138                         } else if (from[0] == '%') {
 139                                 /* substitute format char */
 140                                 unsigned int i;
 141
 142                                 if (from[1] == '%') {
 143                                         from++;
 144                                         goto copy;
 145                                 }
 146
 147                                 for (i = 0; i < ELEMENTSOF(map); i++) {
 148                                         if (from[1] == map[i].fmt) {
 149                                                 type = map[i].type;
 150                                                 from += 2;
 151                                                 goto subst;
 152                                         }
 153                                 }
 154                         }
 155 copy:
 156                         /* copy char */
 157                         if (l == 0)
 158                                 goto out;
 159                         s[0] = from[0];
 160                         from++;
 161                         s++;
 162                         l--;
 163                 }
 164
 165                 goto out;
 166 subst:
 167                 /* extract possible $format{attr} */
 168                 if (from[0] == '{') {
 169                         unsigned int i;
 170
 171                         from++;
 172                         for (i = 0; from[i] != '}'; i++) {
 173                                 if (from[i] == '\0') {
 174                                         log_error("missing closing brace for format '%s'", src);
 175                                         goto out;
 176                                 }
 177                         }
 178                         if (i >= sizeof(attrbuf))
 179                                 goto out;
 180                         memcpy(attrbuf, from, i);
 181                         attrbuf[i] = '\0';
 182                         from += i+1;
 183                         attr = attrbuf;
 184                 } else {
 185                         attr = NULL;
 186                 }
 187
 188                 switch (type) {
 189                 case SUBST_DEVPATH:
 190                         l = strpcpy(&s, l, udev_device_get_devpath(dev));
 191                         break;
 192                 case SUBST_KERNEL:
 193                         l = strpcpy(&s, l, udev_device_get_sysname(dev));
 194                         break;
 195                 case SUBST_KERNEL_NUMBER:
 196                         if (udev_device_get_sysnum(dev) == NULL)
 197                                 break;
 198                         l = strpcpy(&s, l, udev_device_get_sysnum(dev));
 199                         break;
 200                 case SUBST_ID:
 201                         if (event->dev_parent == NULL)
 202                                 break;
 203                         l = strpcpy(&s, l, udev_device_get_sysname(event->dev_parent));
 204                         break;
 205                 case SUBST_DRIVER: {
 206                         const char *driver;
 207
 208                         if (event->dev_parent == NULL)
 209                                 break;
 210
 211                         driver = udev_device_get_driver(event->dev_parent);
 212                         if (driver == NULL)
 213                                 break;
 214                         l = strpcpy(&s, l, driver);
 215                         break;
 216                 }
 217                 case SUBST_MAJOR: {
 218                         char num[UTIL_PATH_SIZE];
 219
 220                         sprintf(num, "%d", major(udev_device_get_devnum(dev)));
 221                         l = strpcpy(&s, l, num);
 222                         break;
 223                 }
 224                 case SUBST_MINOR: {
 225                         char num[UTIL_PATH_SIZE];
 226
 227                         sprintf(num, "%d", minor(udev_device_get_devnum(dev)));
 228                         l = strpcpy(&s, l, num);
 229                         break;
 230                 }
 231                 case SUBST_RESULT: {
 232                         char *rest;
 233                         int i;
 234
 235                         if (event->program_result == NULL)
 236                                 break;
 237                         /* get part part of the result string */
 238                         i = 0;
 239                         if (attr != NULL)
 240                                 i = strtoul(attr, &rest, 10);
 241                         if (i > 0) {
 242                                 char result[UTIL_PATH_SIZE];
 243                                 char tmp[UTIL_PATH_SIZE];
 244                                 char *cpos;
 245
 246                                 strscpy(result, sizeof(result), event->program_result);
 247                                 cpos = result;
 248                                 while (--i) {
 249                                         while (cpos[0] != '\0' && !isspace(cpos[0]))
 250                                                 cpos++;
 251                                         while (isspace(cpos[0]))
 252                                                 cpos++;
 253                                         if (cpos[0] == '\0')
 254                                                 break;
 255                                 }
 256                                 if (i > 0) {
 257                                         log_error("requested part of result string not found");
 258                                         break;
 259                                 }
 260                                 strscpy(tmp, sizeof(tmp), cpos);
 261                                 /* %{2+}c copies the whole string from the second part on */
 262                                 if (rest[0] != '+') {
 263                                         cpos = strchr(tmp, ' ');
 264                                         if (cpos)
 265                                                 cpos[0] = '\0';
 266                                 }
 267                                 l = strpcpy(&s, l, tmp);
 268                         } else {
 269                                 l = strpcpy(&s, l, event->program_result);
 270                         }
 271                         break;
 272                 }
 273                 case SUBST_ATTR: {
 274                         const char *value = NULL;
 275                         char vbuf[UTIL_NAME_SIZE];
 276                         size_t len;
 277                         int count;
 278
 279                         if (attr == NULL) {
 280                                 log_error("missing file parameter for attr");
 281                                 break;
 282                         }
 283
 284                         /* try to read the value specified by "[dmi/id]product_name" */
 285                         if (util_resolve_subsys_kernel(event->udev, attr, vbuf, sizeof(vbuf), 1) == 0)
 286                                 value = vbuf;
 287
 288                         /* try to read the attribute the device */
 289                         if (value == NULL)
 290                                 value = udev_device_get_sysattr_value(event->dev, attr);
 291
 292                         /* try to read the attribute of the parent device, other matches have selected */
 293                         if (value == NULL && event->dev_parent != NULL && event->dev_parent != event->dev)
 294                                 value = udev_device_get_sysattr_value(event->dev_parent, attr);
 295
 296                         if (value == NULL)
 297                                 break;
 298
 299                         /* strip trailing whitespace, and replace unwanted characters */
 300                         if (value != vbuf)
 301                                 strscpy(vbuf, sizeof(vbuf), value);
 302                         len = strlen(vbuf);
 303                         while (len > 0 && isspace(vbuf[--len]))
 304                                 vbuf[len] = '\0';
 305                         count = util_replace_chars(vbuf, UDEV_ALLOWED_CHARS_INPUT);
 306                         if (count > 0)
 307                                 log_debug("%i character(s) replaced" , count);
 308                         l = strpcpy(&s, l, vbuf);
 309                         break;
 310                 }
 311                 case SUBST_PARENT: {
 312                         struct udev_device *dev_parent;
 313                         const char *devnode;
 314
 315                         dev_parent = udev_device_get_parent(event->dev);
 316                         if (dev_parent == NULL)
 317                                 break;
 318                         devnode = udev_device_get_devnode(dev_parent);
 319                         if (devnode != NULL)
 320                                 l = strpcpy(&s, l, devnode + strlen("/dev/"));
 321                         break;
 322                 }
 323                 case SUBST_DEVNODE:
 324                         if (udev_device_get_devnode(dev) != NULL)
 325                                 l = strpcpy(&s, l, udev_device_get_devnode(dev));
 326                         break;
 327                 case SUBST_NAME:
 328                         if (event->name != NULL)
 329                                 l = strpcpy(&s, l, event->name);
 330                         else if (udev_device_get_devnode(dev) != NULL)
 331                                 l = strpcpy(&s, l, udev_device_get_devnode(dev) + strlen("/dev/"));
 332                         else
 333                                 l = strpcpy(&s, l, udev_device_get_sysname(dev));
 334                         break;
 335                 case SUBST_LINKS: {
 336                         struct udev_list_entry *list_entry;
 337
 338                         list_entry = udev_device_get_devlinks_list_entry(dev);
 339                         if (list_entry == NULL)
 340                                 break;
 341                         l = strpcpy(&s, l, udev_list_entry_get_name(list_entry) + strlen("/dev/"));
 342                         udev_list_entry_foreach(list_entry, udev_list_entry_get_next(list_entry))
 343                                 l = strpcpyl(&s, l, " ", udev_list_entry_get_name(list_entry) + strlen("/dev/"), NULL);
 344                         break;
 345                 }
 346                 case SUBST_ROOT:
 347                         l = strpcpy(&s, l, "/dev");
 348                         break;
 349                 case SUBST_SYS:
 350                         l = strpcpy(&s, l, "/sys");
 351                         break;
 352                 case SUBST_ENV:
 353                         if (attr == NULL) {
 354                                 break;
 355                         } else {
 356                                 const char *value;
 357
 358                                 value = udev_device_get_property_value(event->dev, attr);
 359                                 if (value == NULL)
 360                                         break;
 361                                 l = strpcpy(&s, l, value);
 362                                 break;
 363                         }
 364                 default:
 365                         log_error("unknown substitution type=%i", type);
 366                         break;
 367                 }
 368         }
 369
 370 out:
 371         s[0] = '\0';
 372         return l;
 373 }
 374
 375 static int spawn_exec(struct udev_event *event,
 376                       const char *cmd, char *const argv[], char **envp, const sigset_t *sigmask,
 377                       int fd_stdout, int fd_stderr) {
 378         int err;
 379         int fd;
 380
 381         /* discard child output or connect to pipe */
 382         fd = open("/dev/null", O_RDWR);
 383         if (fd >= 0) {
 384                 dup2(fd, STDIN_FILENO);
 385                 if (fd_stdout < 0)
 386                         dup2(fd, STDOUT_FILENO);
 387                 if (fd_stderr < 0)
 388                         dup2(fd, STDERR_FILENO);
 389                 close(fd);
 390         } else {
 391                 log_error("open /dev/null failed: %m");
 392         }
 393
 394         /* connect pipes to std{out,err} */
 395         if (fd_stdout >= 0) {
 396                 dup2(fd_stdout, STDOUT_FILENO);
 397                         close(fd_stdout);
 398         }
 399         if (fd_stderr >= 0) {
 400                 dup2(fd_stderr, STDERR_FILENO);
 401                 close(fd_stderr);
 402         }
 403
 404         /* terminate child in case parent goes away */
 405         prctl(PR_SET_PDEATHSIG, SIGTERM);
 406
 407         /* restore original udev sigmask before exec */
 408         if (sigmask)
 409                 sigprocmask(SIG_SETMASK, sigmask, NULL);
 410
 411         execve(argv[0], argv, envp);
 412
 413         /* exec failed */
 414         err = -errno;
 415         log_error("failed to execute '%s' '%s': %m", argv[0], cmd);
 416         return err;
 417 }
 418
 419 static void spawn_read(struct udev_event *event,
 420                        usec_t timeout_usec,
 421                        const char *cmd,
 422                        int fd_stdout, int fd_stderr,
 423                        char *result, size_t ressize) {
 424         size_t respos = 0;
 425         int fd_ep = -1;
 426         struct epoll_event ep_outpipe, ep_errpipe;
 427
 428         /* read from child if requested */
 429         if (fd_stdout < 0 && fd_stderr < 0)
 430                 return;
 431
 432         fd_ep = epoll_create1(EPOLL_CLOEXEC);
 433         if (fd_ep < 0) {
 434                 log_error("error creating epoll fd: %m");
 435                 goto out;
 436         }
 437
 438         if (fd_stdout >= 0) {
 439                 memzero(&ep_outpipe, sizeof(struct epoll_event));
 440                 ep_outpipe.events = EPOLLIN;
 441                 ep_outpipe.data.ptr = &fd_stdout;
 442                 if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_stdout, &ep_outpipe) < 0) {
 443                         log_error("fail to add fd to epoll: %m");
 444                         goto out;
 445                 }
 446         }
 447
 448         if (fd_stderr >= 0) {
 449                 memzero(&ep_errpipe, sizeof(struct epoll_event));
 450                 ep_errpipe.events = EPOLLIN;
 451                 ep_errpipe.data.ptr = &fd_stderr;
 452                 if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_stderr, &ep_errpipe) < 0) {
 453                         log_error("fail to add fd to epoll: %m");
 454                         goto out;
 455                 }
 456         }
 457
 458         /* read child output */
 459         while (fd_stdout >= 0 || fd_stderr >= 0) {
 460                 int timeout;
 461                 int fdcount;
 462                 struct epoll_event ev[4];
 463                 int i;
 464
 465                 if (timeout_usec > 0) {
 466                         usec_t age_usec;
 467
 468                         age_usec = now(CLOCK_MONOTONIC) - event->birth_usec;
 469                         if (age_usec >= timeout_usec) {
 470                                 log_error("timeout '%s'", cmd);
 471                                 goto out;
 472                         }
 473                         timeout = ((timeout_usec - age_usec) / USEC_PER_MSEC) + MSEC_PER_SEC;
 474                 } else {
 475                         timeout = -1;
 476                 }
 477
 478                 fdcount = epoll_wait(fd_ep, ev, ELEMENTSOF(ev), timeout);
 479                 if (fdcount < 0) {
 480                         if (errno == EINTR)
 481                                 continue;
 482                         log_error("failed to poll: %m");
 483                         goto out;
 484                 }
 485                 if (fdcount == 0) {
 486                         log_error("timeout '%s'", cmd);
 487                         goto out;
 488                 }
 489
 490                 for (i = 0; i < fdcount; i++) {
 491                         int *fd = (int *)ev[i].data.ptr;
 492
 493                         if (ev[i].events & EPOLLIN) {
 494                                 ssize_t count;
 495                                 char buf[4096];
 496
 497                                 count = read(*fd, buf, sizeof(buf)-1);
 498                                 if (count <= 0)
 499                                         continue;
 500                                 buf[count] = '\0';
 501
 502                                 /* store stdout result */
 503                                 if (result != NULL && *fd == fd_stdout) {
 504                                         if (respos + count < ressize) {
 505                                                 memcpy(&result[respos], buf, count);
 506                                                 respos += count;
 507                                         } else {
 508                                                 log_error("'%s' ressize %zd too short", cmd, ressize);
 509                                         }
 510                                 }
 511
 512                                 /* log debug output only if we watch stderr */
 513                                 if (fd_stderr >= 0) {
 514                                         char *pos;
 515                                         char *line;
 516
 517                                         pos = buf;
 518                                         while ((line = strsep(&pos, "\n"))) {
 519                                                 if (pos != NULL || line[0] != '\0')
 520                                                         log_debug("'%s'(%s) '%s'", cmd, *fd == fd_stdout ? "out" : "err" , line);
 521                                         }
 522                                 }
 523                         } else if (ev[i].events & EPOLLHUP) {
 524                                 if (epoll_ctl(fd_ep, EPOLL_CTL_DEL, *fd, NULL) < 0) {
 525                                         log_error("failed to remove fd from epoll: %m");
 526                                         goto out;
 527                                 }
 528                                 *fd = -1;
 529                         }
 530                 }
 531         }
 532
 533         /* return the child's stdout string */
 534         if (result != NULL)
 535                 result[respos] = '\0';
 536 out:
 537         if (fd_ep >= 0)
 538                 close(fd_ep);
 539 }
 540
 541 static int spawn_wait(struct udev_event *event,
 542                       usec_t timeout_usec,
 543                       const char *cmd, pid_t pid) {
 544         struct pollfd pfd[1];
 545         int err = 0;
 546
 547         pfd[0].events = POLLIN;
 548         pfd[0].fd = event->fd_signal;
 549
 550         while (pid > 0) {
 551                 int timeout;
 552                 int fdcount;
 553
 554                 if (timeout_usec > 0) {
 555                         usec_t age_usec;
 556
 557                         age_usec = now(CLOCK_MONOTONIC) - event->birth_usec;
 558                         if (age_usec >= timeout_usec)
 559                                 timeout = 1000;
 560                         else
 561                                 timeout = ((timeout_usec - age_usec) / USEC_PER_MSEC) + MSEC_PER_SEC;
 562                 } else {
 563                         timeout = -1;
 564                 }
 565
 566                 fdcount = poll(pfd, 1, timeout);
 567                 if (fdcount < 0) {
 568                         if (errno == EINTR)
 569                                 continue;
 570                         err = -errno;
 571                         log_error("failed to poll: %m");
 572                         goto out;
 573                 }
 574                 if (fdcount == 0) {
 575                         log_error("timeout: killing '%s' [%u]", cmd, pid);
 576                         kill(pid, SIGKILL);
 577                 }
 578
 579                 if (pfd[0].revents & POLLIN) {
 580                         struct signalfd_siginfo fdsi;
 581                         int status;
 582                         ssize_t size;
 583
 584                         size = read(event->fd_signal, &fdsi, sizeof(struct signalfd_siginfo));
 585                         if (size != sizeof(struct signalfd_siginfo))
 586                                 continue;
 587
 588                         switch (fdsi.ssi_signo) {
 589                         case SIGTERM:
 590                                 event->sigterm = true;
 591                                 break;
 592                         case SIGCHLD:
 593                                 if (waitpid(pid, &status, WNOHANG) < 0)
 594                                         break;
 595                                 if (WIFEXITED(status)) {
 596                                         log_debug("'%s' [%u] exit with return code %i", cmd, pid, WEXITSTATUS(status));
 597                                         if (WEXITSTATUS(status) != 0)
 598                                                 err = -1;
 599                                 } else if (WIFSIGNALED(status)) {
 600                                         log_error("'%s' [%u] terminated by signal %i (%s)", cmd, pid, WTERMSIG(status), strsignal(WTERMSIG(status)));
 601                                         err = -1;
 602                                 } else if (WIFSTOPPED(status)) {
 603                                         log_error("'%s' [%u] stopped", cmd, pid);
 604                                         err = -1;
 605                                 } else if (WIFCONTINUED(status)) {
 606                                         log_error("'%s' [%u] continued", cmd, pid);
 607                                         err = -1;
 608                                 } else {
 609                                         log_error("'%s' [%u] exit with status 0x%04x", cmd, pid, status);
 610                                         err = -1;
 611                                 }
 612                                 pid = 0;
 613                                 break;
 614                         }
 615                 }
 616         }
 617 out:
 618         return err;
 619 }
 620
 621 int udev_build_argv(struct udev *udev, char *cmd, int *argc, char *argv[]) {
 622         int i = 0;
 623         char *pos;
 624
 625         if (strchr(cmd, ' ') == NULL) {
 626                 argv[i++] = cmd;
 627                 goto out;
 628         }
 629
 630         pos = cmd;
 631         while (pos != NULL && pos[0] != '\0') {
 632                 if (pos[0] == '\'') {
 633                         /* do not separate quotes */
 634                         pos++;
 635                         argv[i] = strsep(&pos, "\'");
 636                         if (pos != NULL)
 637                                 while (pos[0] == ' ')
 638                                         pos++;
 639                 } else {
 640                         argv[i] = strsep(&pos, " ");
 641                         if (pos != NULL)
 642                                 while (pos[0] == ' ')
 643                                         pos++;
 644                 }
 645                 i++;
 646         }
 647 out:
 648         argv[i] = NULL;
 649         if (argc)
 650                 *argc = i;
 651         return 0;
 652 }
 653
 654 int udev_event_spawn(struct udev_event *event,
 655                      usec_t timeout_usec,
 656                      const char *cmd, char **envp, const sigset_t *sigmask,
 657                      char *result, size_t ressize) {
 658         struct udev *udev = event->udev;
 659         int outpipe[2] = {-1, -1};
 660         int errpipe[2] = {-1, -1};
 661         pid_t pid;
 662         char arg[UTIL_PATH_SIZE];
 663         char *argv[128];
 664         char program[UTIL_PATH_SIZE];
 665         int err = 0;
 666
 667         strscpy(arg, sizeof(arg), cmd);
 668         udev_build_argv(event->udev, arg, NULL, argv);
 669
 670         /* pipes from child to parent */
 671         if (result != NULL || udev_get_log_priority(udev) >= LOG_INFO) {
 672                 if (pipe2(outpipe, O_NONBLOCK) != 0) {
 673                         err = -errno;
 674                         log_error("pipe failed: %m");
 675                         goto out;
 676                 }
 677         }
 678         if (udev_get_log_priority(udev) >= LOG_INFO) {
 679                 if (pipe2(errpipe, O_NONBLOCK) != 0) {
 680                         err = -errno;
 681                         log_error("pipe failed: %m");
 682                         goto out;
 683                 }
 684         }
 685
 686         /* allow programs in /usr/lib/udev/ to be called without the path */
 687         if (argv[0][0] != '/') {
 688                 strscpyl(program, sizeof(program), UDEVLIBEXECDIR "/", argv[0], NULL);
 689                 argv[0] = program;
 690         }
 691
 692         pid = fork();
 693         switch(pid) {
 694         case 0:
 695                 /* child closes parent's ends of pipes */
 696                 if (outpipe[READ_END] >= 0) {
 697                         close(outpipe[READ_END]);
 698                         outpipe[READ_END] = -1;
 699                 }
 700                 if (errpipe[READ_END] >= 0) {
 701                         close(errpipe[READ_END]);
 702                         errpipe[READ_END] = -1;
 703                 }
 704
 705                 log_debug("starting '%s'", cmd);
 706
 707                 spawn_exec(event, cmd, argv, envp, sigmask,
 708                            outpipe[WRITE_END], errpipe[WRITE_END]);
 709
 710                 _exit(2 );
 711         case -1:
 712                 log_error("fork of '%s' failed: %m", cmd);
 713                 err = -1;
 714                 goto out;
 715         default:
 716                 /* parent closed child's ends of pipes */
 717                 if (outpipe[WRITE_END] >= 0) {
 718                         close(outpipe[WRITE_END]);
 719                         outpipe[WRITE_END] = -1;
 720                 }
 721                 if (errpipe[WRITE_END] >= 0) {
 722                         close(errpipe[WRITE_END]);
 723                         errpipe[WRITE_END] = -1;
 724                 }
 725
 726                 spawn_read(event,
 727                            timeout_usec,
 728                            cmd,
 729                            outpipe[READ_END], errpipe[READ_END],
 730                            result, ressize);
 731
 732                 err = spawn_wait(event, timeout_usec, cmd, pid);
 733         }
 734
 735 out:
 736         if (outpipe[READ_END] >= 0)
 737                 close(outpipe[READ_END]);
 738         if (outpipe[WRITE_END] >= 0)
 739                 close(outpipe[WRITE_END]);
 740         if (errpipe[READ_END] >= 0)
 741                 close(errpipe[READ_END]);
 742         if (errpipe[WRITE_END] >= 0)
 743                 close(errpipe[WRITE_END]);
 744         return err;
 745 }
 746
 747 static int rename_netif(struct udev_event *event) {
 748         struct udev_device *dev = event->dev;
 749         _cleanup_rtnl_unref_ sd_rtnl *rtnl = NULL;
 750         char name[IFNAMSIZ];
 751         const char *oldname;
 752         int r;
 753
 754         oldname = udev_device_get_sysname(dev);
 755
 756         log_debug("changing net interface name from '%s' to '%s'",
 757                   oldname, event->name);
 758
 759         strscpy(name, IFNAMSIZ, event->name);
 760
 761         r = sd_rtnl_open(&rtnl, 0);
 762         if (r < 0)
 763                 return r;
 764
 765         r = rtnl_set_link_name(rtnl, udev_device_get_ifindex(dev), name);
 766         if (r < 0)
 767                 log_error("error changing net interface name %s to %s: %s",
 768                           oldname, name, strerror(-r));
 769         else
 770                 print_kmsg("renamed network interface %s to %s\n", oldname, name);
 771
 772         return r;
 773 }
 774
 775 void udev_event_execute_rules(struct udev_event *event,
 776                               usec_t timeout_usec,
 777                               struct udev_rules *rules, const sigset_t *sigmask) {
 778         struct udev_device *dev = event->dev;
 779
 780         if (udev_device_get_subsystem(dev) == NULL)
 781                 return;
 782
 783         if (streq(udev_device_get_action(dev), "remove")) {
 784                 udev_device_read_db(dev, NULL);
 785                 udev_device_delete_db(dev);
 786                 udev_device_tag_index(dev, NULL, false);
 787
 788                 if (major(udev_device_get_devnum(dev)) != 0)
 789                         udev_watch_end(event->udev, dev);
 790
 791                 udev_rules_apply_to_event(rules, event, timeout_usec, sigmask);
 792
 793                 if (major(udev_device_get_devnum(dev)) != 0)
 794                         udev_node_remove(dev);
 795         } else {
 796                 event->dev_db = udev_device_new(event->udev);
 797                 if (event->dev_db != NULL) {
 798                         udev_device_set_syspath(event->dev_db, udev_device_get_syspath(dev));
 799                         udev_device_set_subsystem(event->dev_db, udev_device_get_subsystem(dev));
 800                         udev_device_read_db(event->dev_db, NULL);
 801                         udev_device_set_info_loaded(event->dev_db);
 802
 803                         /* disable watch during event processing */
 804                         if (major(udev_device_get_devnum(dev)) != 0)
 805                                 udev_watch_end(event->udev, event->dev_db);
 806                 }
 807
 808                 if (major(udev_device_get_devnum(dev)) == 0 &&
 809                     streq(udev_device_get_action(dev), "move")) {
 810                         struct udev_list_entry *entry;
 811
 812                         for ((entry = udev_device_get_properties_list_entry(event->dev_db)); entry; entry = udev_list_entry_get_next(entry)) {
 813                                 const char *key, *value;
 814                                 struct udev_list_entry *property;
 815
 816                                 key = udev_list_entry_get_name(entry);
 817                                 value = udev_list_entry_get_value(entry);
 818
 819                                 property = udev_device_add_property(event->dev, key, value);
 820                                 udev_list_entry_set_num(property, true);
 821                         }
 822                 }
 823
 824                 udev_rules_apply_to_event(rules, event, timeout_usec, sigmask);
 825
 826                 /* rename a new network interface, if needed */
 827                 if (udev_device_get_ifindex(dev) > 0 && streq(udev_device_get_action(dev), "add") &&
 828                     event->name != NULL && !streq(event->name, udev_device_get_sysname(dev))) {
 829                         char syspath[UTIL_PATH_SIZE];
 830                         char *pos;
 831                         int r;
 832
 833                         r = rename_netif(event);
 834                         if (r >= 0) {
 835                                 log_debug("renamed netif to '%s'", event->name);
 836
 837                                 /* remember old name */
 838                                 udev_device_add_property(dev, "INTERFACE_OLD", udev_device_get_sysname(dev));
 839
 840                                 /* now change the devpath, because the kernel device name has changed */
 841                                 strscpy(syspath, sizeof(syspath), udev_device_get_syspath(dev));
 842                                 pos = strrchr(syspath, '/');
 843                                 if (pos != NULL) {
 844                                         pos++;
 845                                         strscpy(pos, sizeof(syspath) - (pos - syspath), event->name);
 846                                         udev_device_set_syspath(event->dev, syspath);
 847                                         udev_device_add_property(dev, "INTERFACE", udev_device_get_sysname(dev));
 848                                         log_debug("changed devpath to '%s'", udev_device_get_devpath(dev));
 849                                 }
 850                         }
 851                 }
 852
 853                 if (major(udev_device_get_devnum(dev)) > 0) {
 854                         bool apply;
 855
 856                         /* remove/update possible left-over symlinks from old database entry */
 857                         if (event->dev_db != NULL)
 858                                 udev_node_update_old_links(dev, event->dev_db);
 859
 860                         if (!event->owner_set)
 861                                 event->uid = udev_device_get_devnode_uid(dev);
 862
 863                         if (!event->group_set)
 864                                 event->gid = udev_device_get_devnode_gid(dev);
 865
 866                         if (!event->mode_set) {
 867                                 if (udev_device_get_devnode_mode(dev) > 0) {
 868                                         /* kernel supplied value */
 869                                         event->mode = udev_device_get_devnode_mode(dev);
 870                                 } else if (event->gid > 0) {
 871                                         /* default 0660 if a group is assigned */
 872                                         event->mode = 0660;
 873                                 } else {
 874                                         /* default 0600 */
 875                                         event->mode = 0600;
 876                                 }
 877                         }
 878
 879                         apply = streq(udev_device_get_action(dev), "add") || event->owner_set || event->group_set || event->mode_set;
 880                         udev_node_add(dev, apply, event->mode, event->uid, event->gid, &event->seclabel_list);
 881                 }
 882
 883                 /* preserve old, or get new initialization timestamp */
 884                 if (event->dev_db != NULL && udev_device_get_usec_initialized(event->dev_db) > 0)
 885                         udev_device_set_usec_initialized(event->dev, udev_device_get_usec_initialized(event->dev_db));
 886                 else if (udev_device_get_usec_initialized(event->dev) == 0)
 887                         udev_device_set_usec_initialized(event->dev, now(CLOCK_MONOTONIC));
 888
 889                 /* (re)write database file */
 890                 udev_device_update_db(dev);
 891                 udev_device_tag_index(dev, event->dev_db, true);
 892                 udev_device_set_is_initialized(dev);
 893
 894                 udev_device_unref(event->dev_db);
 895                 event->dev_db = NULL;
 896         }
 897 }
 898
 899 void udev_event_execute_run(struct udev_event *event, usec_t timeout_usec, const sigset_t *sigmask) {
 900         struct udev_list_entry *list_entry;
 901
 902         udev_list_entry_foreach(list_entry, udev_list_get_entry(&event->run_list)) {
 903                 const char *cmd = udev_list_entry_get_name(list_entry);
 904                 enum udev_builtin_cmd builtin_cmd = udev_list_entry_get_num(list_entry);
 905
 906                 if (builtin_cmd < UDEV_BUILTIN_MAX) {
 907                         char command[UTIL_PATH_SIZE];
 908
 909                         udev_event_apply_format(event, cmd, command, sizeof(command));
 910                         udev_builtin_run(event->dev, builtin_cmd, command, false);
 911                 } else {
 912                         char program[UTIL_PATH_SIZE];
 913                         char **envp;
 914
 915                         if (event->exec_delay > 0) {
 916                                 log_debug("delay execution of '%s'", program);
 917                                 sleep(event->exec_delay);
 918                         }
 919
 920                         udev_event_apply_format(event, cmd, program, sizeof(program));
 921                         envp = udev_device_get_properties_envp(event->dev);
 922                         udev_event_spawn(event, timeout_usec, program, envp, sigmask, NULL, 0);
 923                 }
 924         }
 925 }