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 <ctype.h>
  19 #include <errno.h>
  20 #include <fcntl.h>
  21 #include <net/if.h>
  22 #include <poll.h>
  23 #include <stddef.h>
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <string.h>
  27 #include <sys/epoll.h>
  28 #include <sys/prctl.h>
  29 #include <sys/signalfd.h>
  30 #include <sys/wait.h>
  31 #include <unistd.h>
  32
  33 #include "alloc-util.h"
  34 #include "fd-util.h"
  35 #include "formats-util.h"
  36 #include "netlink-util.h"
  37 #include "process-util.h"
  38 #include "signal-util.h"
  39 #include "string-util.h"
  40 #include "udev.h"
  41
  42 typedef struct Spawn {
  43         const char *cmd;
  44         pid_t pid;
  45         usec_t timeout_warn;
  46         usec_t timeout;
  47         bool accept_failure;
  48 } Spawn;
  49
  50 struct udev_event *udev_event_new(struct udev_device *dev) {
  51         struct udev *udev = udev_device_get_udev(dev);
  52         struct udev_event *event;
  53
  54         event = new0(struct udev_event, 1);
  55         if (event == NULL)
  56                 return NULL;
  57         event->dev = dev;
  58         event->udev = udev;
  59         udev_list_init(udev, &event->run_list, false);
  60         udev_list_init(udev, &event->seclabel_list, false);
  61         event->birth_usec = clock_boottime_or_monotonic();
  62         return event;
  63 }
  64
  65 void udev_event_unref(struct udev_event *event) {
  66         if (event == NULL)
  67                 return;
  68         sd_netlink_unref(event->rtnl);
  69         udev_list_cleanup(&event->run_list);
  70         udev_list_cleanup(&event->seclabel_list);
  71         free(event->program_result);
  72         free(event->name);
  73         free(event);
  74 }
  75
  76 size_t udev_event_apply_format(struct udev_event *event, const char *src, char *dest, size_t size) {
  77         struct udev_device *dev = event->dev;
  78         enum subst_type {
  79                 SUBST_UNKNOWN,
  80                 SUBST_DEVNODE,
  81                 SUBST_ATTR,
  82                 SUBST_ENV,
  83                 SUBST_KERNEL,
  84                 SUBST_KERNEL_NUMBER,
  85                 SUBST_DRIVER,
  86                 SUBST_DEVPATH,
  87                 SUBST_ID,
  88                 SUBST_MAJOR,
  89                 SUBST_MINOR,
  90                 SUBST_RESULT,
  91                 SUBST_PARENT,
  92                 SUBST_NAME,
  93                 SUBST_LINKS,
  94                 SUBST_ROOT,
  95                 SUBST_SYS,
  96         };
  97         static const struct subst_map {
  98                 const char *name;
  99                 const char fmt;
 100                 enum subst_type type;
 101         } map[] = {
 102                 { .name = "devnode",  .fmt = 'N', .type = SUBST_DEVNODE },
 103                 { .name = "tempnode", .fmt = 'N', .type = SUBST_DEVNODE },
 104                 { .name = "attr",     .fmt = 's', .type = SUBST_ATTR },
 105                 { .name = "sysfs",    .fmt = 's', .type = SUBST_ATTR },
 106                 { .name = "env",      .fmt = 'E', .type = SUBST_ENV },
 107                 { .name = "kernel",   .fmt = 'k', .type = SUBST_KERNEL },
 108                 { .name = "number",   .fmt = 'n', .type = SUBST_KERNEL_NUMBER },
 109                 { .name = "driver",   .fmt = 'd', .type = SUBST_DRIVER },
 110                 { .name = "devpath",  .fmt = 'p', .type = SUBST_DEVPATH },
 111                 { .name = "id",       .fmt = 'b', .type = SUBST_ID },
 112                 { .name = "major",    .fmt = 'M', .type = SUBST_MAJOR },
 113                 { .name = "minor",    .fmt = 'm', .type = SUBST_MINOR },
 114                 { .name = "result",   .fmt = 'c', .type = SUBST_RESULT },
 115                 { .name = "parent",   .fmt = 'P', .type = SUBST_PARENT },
 116                 { .name = "name",     .fmt = 'D', .type = SUBST_NAME },
 117                 { .name = "links",    .fmt = 'L', .type = SUBST_LINKS },
 118                 { .name = "root",     .fmt = 'r', .type = SUBST_ROOT },
 119                 { .name = "sys",      .fmt = 'S', .type = SUBST_SYS },
 120         };
 121         const char *from;
 122         char *s;
 123         size_t l;
 124
 125         assert(dev);
 126
 127         from = src;
 128         s = dest;
 129         l = size;
 130
 131         for (;;) {
 132                 enum subst_type type = SUBST_UNKNOWN;
 133                 char attrbuf[UTIL_PATH_SIZE];
 134                 char *attr = NULL;
 135
 136                 while (from[0] != '\0') {
 137                         if (from[0] == '$') {
 138                                 /* substitute named variable */
 139                                 unsigned int i;
 140
 141                                 if (from[1] == '$') {
 142                                         from++;
 143                                         goto copy;
 144                                 }
 145
 146                                 for (i = 0; i < ELEMENTSOF(map); i++) {
 147                                         if (startswith(&from[1], map[i].name)) {
 148                                                 type = map[i].type;
 149                                                 from += strlen(map[i].name)+1;
 150                                                 goto subst;
 151                                         }
 152                                 }
 153                         } else if (from[0] == '%') {
 154                                 /* substitute format char */
 155                                 unsigned int i;
 156
 157                                 if (from[1] == '%') {
 158                                         from++;
 159                                         goto copy;
 160                                 }
 161
 162                                 for (i = 0; i < ELEMENTSOF(map); i++) {
 163                                         if (from[1] == map[i].fmt) {
 164                                                 type = map[i].type;
 165                                                 from += 2;
 166                                                 goto subst;
 167                                         }
 168                                 }
 169                         }
 170 copy:
 171                         /* copy char */
 172                         if (l == 0)
 173                                 goto out;
 174                         s[0] = from[0];
 175                         from++;
 176                         s++;
 177                         l--;
 178                 }
 179
 180                 goto out;
 181 subst:
 182                 /* extract possible $format{attr} */
 183                 if (from[0] == '{') {
 184                         unsigned int i;
 185
 186                         from++;
 187                         for (i = 0; from[i] != '}'; i++) {
 188                                 if (from[i] == '\0') {
 189                                         log_error("missing closing brace for format '%s'", src);
 190                                         goto out;
 191                                 }
 192                         }
 193                         if (i >= sizeof(attrbuf))
 194                                 goto out;
 195                         memcpy(attrbuf, from, i);
 196                         attrbuf[i] = '\0';
 197                         from += i+1;
 198                         attr = attrbuf;
 199                 } else {
 200                         attr = NULL;
 201                 }
 202
 203                 switch (type) {
 204                 case SUBST_DEVPATH:
 205                         l = strpcpy(&s, l, udev_device_get_devpath(dev));
 206                         break;
 207                 case SUBST_KERNEL:
 208                         l = strpcpy(&s, l, udev_device_get_sysname(dev));
 209                         break;
 210                 case SUBST_KERNEL_NUMBER:
 211                         if (udev_device_get_sysnum(dev) == NULL)
 212                                 break;
 213                         l = strpcpy(&s, l, udev_device_get_sysnum(dev));
 214                         break;
 215                 case SUBST_ID:
 216                         if (event->dev_parent == NULL)
 217                                 break;
 218                         l = strpcpy(&s, l, udev_device_get_sysname(event->dev_parent));
 219                         break;
 220                 case SUBST_DRIVER: {
 221                         const char *driver;
 222
 223                         if (event->dev_parent == NULL)
 224                                 break;
 225
 226                         driver = udev_device_get_driver(event->dev_parent);
 227                         if (driver == NULL)
 228                                 break;
 229                         l = strpcpy(&s, l, driver);
 230                         break;
 231                 }
 232                 case SUBST_MAJOR: {
 233                         char num[UTIL_PATH_SIZE];
 234
 235                         sprintf(num, "%u", major(udev_device_get_devnum(dev)));
 236                         l = strpcpy(&s, l, num);
 237                         break;
 238                 }
 239                 case SUBST_MINOR: {
 240                         char num[UTIL_PATH_SIZE];
 241
 242                         sprintf(num, "%u", minor(udev_device_get_devnum(dev)));
 243                         l = strpcpy(&s, l, 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                                 strscpy(result, sizeof(result), event->program_result);
 262                                 cpos = result;
 263                                 while (--i) {
 264                                         while (cpos[0] != '\0' && !isspace(cpos[0]))
 265                                                 cpos++;
 266                                         while (isspace(cpos[0]))
 267                                                 cpos++;
 268                                         if (cpos[0] == '\0')
 269                                                 break;
 270                                 }
 271                                 if (i > 0) {
 272                                         log_error("requested part of result string not found");
 273                                         break;
 274                                 }
 275                                 strscpy(tmp, sizeof(tmp), cpos);
 276                                 /* %{2+}c copies the whole string from the second part on */
 277                                 if (rest[0] != '+') {
 278                                         cpos = strchr(tmp, ' ');
 279                                         if (cpos)
 280                                                 cpos[0] = '\0';
 281                                 }
 282                                 l = strpcpy(&s, l, tmp);
 283                         } else {
 284                                 l = strpcpy(&s, l, event->program_result);
 285                         }
 286                         break;
 287                 }
 288                 case SUBST_ATTR: {
 289                         const char *value = NULL;
 290                         char vbuf[UTIL_NAME_SIZE];
 291                         size_t len;
 292                         int count;
 293
 294                         if (attr == NULL) {
 295                                 log_error("missing file parameter for attr");
 296                                 break;
 297                         }
 298
 299                         /* try to read the value specified by "[dmi/id]product_name" */
 300                         if (util_resolve_subsys_kernel(event->udev, attr, vbuf, sizeof(vbuf), 1) == 0)
 301                                 value = vbuf;
 302
 303                         /* try to read the attribute the device */
 304                         if (value == NULL)
 305                                 value = udev_device_get_sysattr_value(event->dev, attr);
 306
 307                         /* try to read the attribute of the parent device, other matches have selected */
 308                         if (value == NULL && event->dev_parent != NULL && event->dev_parent != event->dev)
 309                                 value = udev_device_get_sysattr_value(event->dev_parent, attr);
 310
 311                         if (value == NULL)
 312                                 break;
 313
 314                         /* strip trailing whitespace, and replace unwanted characters */
 315                         if (value != vbuf)
 316                                 strscpy(vbuf, sizeof(vbuf), value);
 317                         len = strlen(vbuf);
 318                         while (len > 0 && isspace(vbuf[--len]))
 319                                 vbuf[len] = '\0';
 320                         count = util_replace_chars(vbuf, UDEV_ALLOWED_CHARS_INPUT);
 321                         if (count > 0)
 322                                 log_debug("%i character(s) replaced" , count);
 323                         l = strpcpy(&s, l, vbuf);
 324                         break;
 325                 }
 326                 case SUBST_PARENT: {
 327                         struct udev_device *dev_parent;
 328                         const char *devnode;
 329
 330                         dev_parent = udev_device_get_parent(event->dev);
 331                         if (dev_parent == NULL)
 332                                 break;
 333                         devnode = udev_device_get_devnode(dev_parent);
 334                         if (devnode != NULL)
 335                                 l = strpcpy(&s, l, devnode + strlen("/dev/"));
 336                         break;
 337                 }
 338                 case SUBST_DEVNODE:
 339                         if (udev_device_get_devnode(dev) != NULL)
 340                                 l = strpcpy(&s, l, udev_device_get_devnode(dev));
 341                         break;
 342                 case SUBST_NAME:
 343                         if (event->name != NULL)
 344                                 l = strpcpy(&s, l, event->name);
 345                         else if (udev_device_get_devnode(dev) != NULL)
 346                                 l = strpcpy(&s, l, udev_device_get_devnode(dev) + strlen("/dev/"));
 347                         else
 348                                 l = strpcpy(&s, l, udev_device_get_sysname(dev));
 349                         break;
 350                 case SUBST_LINKS: {
 351                         struct udev_list_entry *list_entry;
 352
 353                         list_entry = udev_device_get_devlinks_list_entry(dev);
 354                         if (list_entry == NULL)
 355                                 break;
 356                         l = strpcpy(&s, l, udev_list_entry_get_name(list_entry) + strlen("/dev/"));
 357                         udev_list_entry_foreach(list_entry, udev_list_entry_get_next(list_entry))
 358                                 l = strpcpyl(&s, l, " ", udev_list_entry_get_name(list_entry) + strlen("/dev/"), NULL);
 359                         break;
 360                 }
 361                 case SUBST_ROOT:
 362                         l = strpcpy(&s, l, "/dev");
 363                         break;
 364                 case SUBST_SYS:
 365                         l = strpcpy(&s, l, "/sys");
 366                         break;
 367                 case SUBST_ENV:
 368                         if (attr == NULL) {
 369                                 break;
 370                         } else {
 371                                 const char *value;
 372
 373                                 value = udev_device_get_property_value(event->dev, attr);
 374                                 if (value == NULL)
 375                                         break;
 376                                 l = strpcpy(&s, l, value);
 377                                 break;
 378                         }
 379                 default:
 380                         log_error("unknown substitution type=%i", type);
 381                         break;
 382                 }
 383         }
 384
 385 out:
 386         s[0] = '\0';
 387         return l;
 388 }
 389
 390 static int spawn_exec(struct udev_event *event,
 391                       const char *cmd, char *const argv[], char **envp,
 392                       int fd_stdout, int fd_stderr) {
 393         _cleanup_close_ int fd = -1;
 394         int r;
 395
 396         /* discard child output or connect to pipe */
 397         fd = open("/dev/null", O_RDWR);
 398         if (fd >= 0) {
 399                 r = dup2(fd, STDIN_FILENO);
 400                 if (r < 0)
 401                         log_warning_errno(errno, "redirecting stdin failed: %m");
 402
 403                 if (fd_stdout < 0) {
 404                         r = dup2(fd, STDOUT_FILENO);
 405                         if (r < 0)
 406                                 log_warning_errno(errno, "redirecting stdout failed: %m");
 407                 }
 408
 409                 if (fd_stderr < 0) {
 410                         r = dup2(fd, STDERR_FILENO);
 411                         if (r < 0)
 412                                 log_warning_errno(errno, "redirecting stderr failed: %m");
 413                 }
 414         } else
 415                 log_warning_errno(errno, "open /dev/null failed: %m");
 416
 417         /* connect pipes to std{out,err} */
 418         if (fd_stdout >= 0) {
 419                 r = dup2(fd_stdout, STDOUT_FILENO);
 420                 if (r < 0)
 421                         log_warning_errno(errno, "redirecting stdout failed: %m");
 422
 423                 fd_stdout = safe_close(fd_stdout);
 424         }
 425
 426         if (fd_stderr >= 0) {
 427                 r = dup2(fd_stderr, STDERR_FILENO);
 428                 if (r < 0)
 429                         log_warning_errno(errno, "redirecting stdout failed: %m");
 430
 431                 fd_stderr = safe_close(fd_stderr);
 432         }
 433
 434         /* terminate child in case parent goes away */
 435         prctl(PR_SET_PDEATHSIG, SIGTERM);
 436
 437         /* restore sigmask before exec */
 438         (void) reset_signal_mask();
 439
 440         execve(argv[0], argv, envp);
 441
 442         /* exec failed */
 443         return log_error_errno(errno, "failed to execute '%s' '%s': %m", argv[0], cmd);
 444 }
 445
 446 static void spawn_read(struct udev_event *event,
 447                        usec_t timeout_usec,
 448                        const char *cmd,
 449                        int fd_stdout, int fd_stderr,
 450                        char *result, size_t ressize) {
 451         _cleanup_close_ int fd_ep = -1;
 452         struct epoll_event ep_outpipe = {
 453                 .events = EPOLLIN,
 454                 .data.ptr = &fd_stdout,
 455         };
 456         struct epoll_event ep_errpipe = {
 457                 .events = EPOLLIN,
 458                 .data.ptr = &fd_stderr,
 459         };
 460         size_t respos = 0;
 461         int r;
 462
 463         /* read from child if requested */
 464         if (fd_stdout < 0 && fd_stderr < 0)
 465                 return;
 466
 467         fd_ep = epoll_create1(EPOLL_CLOEXEC);
 468         if (fd_ep < 0) {
 469                 log_error_errno(errno, "error creating epoll fd: %m");
 470                 return;
 471         }
 472
 473         if (fd_stdout >= 0) {
 474                 r = epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_stdout, &ep_outpipe);
 475                 if (r < 0) {
 476                         log_error_errno(errno, "fail to add stdout fd to epoll: %m");
 477                         return;
 478                 }
 479         }
 480
 481         if (fd_stderr >= 0) {
 482                 r = epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_stderr, &ep_errpipe);
 483                 if (r < 0) {
 484                         log_error_errno(errno, "fail to add stderr fd to epoll: %m");
 485                         return;
 486                 }
 487         }
 488
 489         /* read child output */
 490         while (fd_stdout >= 0 || fd_stderr >= 0) {
 491                 int timeout;
 492                 int fdcount;
 493                 struct epoll_event ev[4];
 494                 int i;
 495
 496                 if (timeout_usec > 0) {
 497                         usec_t age_usec;
 498
 499                         age_usec = clock_boottime_or_monotonic() - event->birth_usec;
 500                         if (age_usec >= timeout_usec) {
 501                                 log_error("timeout '%s'", cmd);
 502                                 return;
 503                         }
 504                         timeout = ((timeout_usec - age_usec) / USEC_PER_MSEC) + MSEC_PER_SEC;
 505                 } else {
 506                         timeout = -1;
 507                 }
 508
 509                 fdcount = epoll_wait(fd_ep, ev, ELEMENTSOF(ev), timeout);
 510                 if (fdcount < 0) {
 511                         if (errno == EINTR)
 512                                 continue;
 513                         log_error_errno(errno, "failed to poll: %m");
 514                         return;
 515                 } else if (fdcount == 0) {
 516                         log_error("timeout '%s'", cmd);
 517                         return;
 518                 }
 519
 520                 for (i = 0; i < fdcount; i++) {
 521                         int *fd = (int *)ev[i].data.ptr;
 522
 523                         if (*fd < 0)
 524                                 continue;
 525
 526                         if (ev[i].events & EPOLLIN) {
 527                                 ssize_t count;
 528                                 char buf[4096];
 529
 530                                 count = read(*fd, buf, sizeof(buf)-1);
 531                                 if (count <= 0)
 532                                         continue;
 533                                 buf[count] = '\0';
 534
 535                                 /* store stdout result */
 536                                 if (result != NULL && *fd == fd_stdout) {
 537                                         if (respos + count < ressize) {
 538                                                 memcpy(&result[respos], buf, count);
 539                                                 respos += count;
 540                                         } else {
 541                                                 log_error("'%s' ressize %zu too short", cmd, ressize);
 542                                         }
 543                                 }
 544
 545                                 /* log debug output only if we watch stderr */
 546                                 if (fd_stderr >= 0) {
 547                                         char *pos;
 548                                         char *line;
 549
 550                                         pos = buf;
 551                                         while ((line = strsep(&pos, "\n"))) {
 552                                                 if (pos != NULL || line[0] != '\0')
 553                                                         log_debug("'%s'(%s) '%s'", cmd, *fd == fd_stdout ? "out" : "err" , line);
 554                                         }
 555                                 }
 556                         } else if (ev[i].events & EPOLLHUP) {
 557                                 r = epoll_ctl(fd_ep, EPOLL_CTL_DEL, *fd, NULL);
 558                                 if (r < 0) {
 559                                         log_error_errno(errno, "failed to remove fd from epoll: %m");
 560                                         return;
 561                                 }
 562                                 *fd = -1;
 563                         }
 564                 }
 565         }
 566
 567         /* return the child's stdout string */
 568         if (result != NULL)
 569                 result[respos] = '\0';
 570 }
 571
 572 static int on_spawn_timeout(sd_event_source *s, uint64_t usec, void *userdata) {
 573         Spawn *spawn = userdata;
 574         char timeout[FORMAT_TIMESTAMP_RELATIVE_MAX];
 575
 576         assert(spawn);
 577
 578         kill_and_sigcont(spawn->pid, SIGKILL);
 579
 580         log_error("spawned process '%s' ["PID_FMT"] timed out after %s, killing", spawn->cmd, spawn->pid,
 581                   format_timestamp_relative(timeout, sizeof(timeout), spawn->timeout));
 582
 583         return 1;
 584 }
 585
 586 static int on_spawn_timeout_warning(sd_event_source *s, uint64_t usec, void *userdata) {
 587         Spawn *spawn = userdata;
 588         char timeout[FORMAT_TIMESTAMP_RELATIVE_MAX];
 589
 590         assert(spawn);
 591
 592         log_warning("spawned process '%s' ["PID_FMT"] is taking longer than %s to complete", spawn->cmd, spawn->pid,
 593                     format_timestamp_relative(timeout, sizeof(timeout), spawn->timeout));
 594
 595         return 1;
 596 }
 597
 598 static int on_spawn_sigchld(sd_event_source *s, const siginfo_t *si, void *userdata) {
 599         Spawn *spawn = userdata;
 600
 601         assert(spawn);
 602
 603         switch (si->si_code) {
 604         case CLD_EXITED:
 605                 if (si->si_status == 0) {
 606                         log_debug("Process '%s' succeeded.", spawn->cmd);
 607                         sd_event_exit(sd_event_source_get_event(s), 0);
 608
 609                         return 1;
 610                 } else if (spawn->accept_failure)
 611                         log_debug("Process '%s' failed with exit code %i.", spawn->cmd, si->si_status);
 612                 else
 613                         log_warning("Process '%s' failed with exit code %i.", spawn->cmd, si->si_status);
 614
 615                 break;
 616         case CLD_KILLED:
 617         case CLD_DUMPED:
 618                 log_warning("Process '%s' terminated by signal %s.", spawn->cmd, signal_to_string(si->si_status));
 619
 620                 break;
 621         default:
 622                 log_error("Process '%s' failed due to unknown reason.", spawn->cmd);
 623         }
 624
 625         sd_event_exit(sd_event_source_get_event(s), -EIO);
 626
 627         return 1;
 628 }
 629
 630 static int spawn_wait(struct udev_event *event,
 631                       usec_t timeout_usec,
 632                       usec_t timeout_warn_usec,
 633                       const char *cmd, pid_t pid,
 634                       bool accept_failure) {
 635         Spawn spawn = {
 636                 .cmd = cmd,
 637                 .pid = pid,
 638                 .accept_failure = accept_failure,
 639         };
 640         _cleanup_(sd_event_unrefp) sd_event *e = NULL;
 641         int r, ret;
 642
 643         r = sd_event_new(&e);
 644         if (r < 0)
 645                 return r;
 646
 647         if (timeout_usec > 0) {
 648                 usec_t usec, age_usec;
 649
 650                 usec = now(clock_boottime_or_monotonic());
 651                 age_usec = usec - event->birth_usec;
 652                 if (age_usec < timeout_usec) {
 653                         if (timeout_warn_usec > 0 && timeout_warn_usec < timeout_usec && age_usec < timeout_warn_usec) {
 654                                 spawn.timeout_warn = timeout_warn_usec - age_usec;
 655
 656                                 r = sd_event_add_time(e, NULL, clock_boottime_or_monotonic(),
 657                                                       usec + spawn.timeout_warn, USEC_PER_SEC,
 658                                                       on_spawn_timeout_warning, &spawn);
 659                                 if (r < 0)
 660                                         return r;
 661                         }
 662
 663                         spawn.timeout = timeout_usec - age_usec;
 664
 665                         r = sd_event_add_time(e, NULL, clock_boottime_or_monotonic(),
 666                                               usec + spawn.timeout, USEC_PER_SEC, on_spawn_timeout, &spawn);
 667                         if (r < 0)
 668                                 return r;
 669                 }
 670         }
 671
 672         r = sd_event_add_child(e, NULL, pid, WEXITED, on_spawn_sigchld, &spawn);
 673         if (r < 0)
 674                 return r;
 675
 676         r = sd_event_loop(e);
 677         if (r < 0)
 678                 return r;
 679
 680         r = sd_event_get_exit_code(e, &ret);
 681         if (r < 0)
 682                 return r;
 683
 684         return ret;
 685 }
 686
 687 int udev_build_argv(struct udev *udev, char *cmd, int *argc, char *argv[]) {
 688         int i = 0;
 689         char *pos;
 690
 691         if (strchr(cmd, ' ') == NULL) {
 692                 argv[i++] = cmd;
 693                 goto out;
 694         }
 695
 696         pos = cmd;
 697         while (pos != NULL && pos[0] != '\0') {
 698                 if (pos[0] == '\'') {
 699                         /* do not separate quotes */
 700                         pos++;
 701                         argv[i] = strsep(&pos, "\'");
 702                         if (pos != NULL)
 703                                 while (pos[0] == ' ')
 704                                         pos++;
 705                 } else {
 706                         argv[i] = strsep(&pos, " ");
 707                         if (pos != NULL)
 708                                 while (pos[0] == ' ')
 709                                         pos++;
 710                 }
 711                 i++;
 712         }
 713 out:
 714         argv[i] = NULL;
 715         if (argc)
 716                 *argc = i;
 717         return 0;
 718 }
 719
 720 int udev_event_spawn(struct udev_event *event,
 721                      usec_t timeout_usec,
 722                      usec_t timeout_warn_usec,
 723                      bool accept_failure,
 724                      const char *cmd,
 725                      char *result, size_t ressize) {
 726         int outpipe[2] = {-1, -1};
 727         int errpipe[2] = {-1, -1};
 728         pid_t pid;
 729         int err = 0;
 730
 731         /* pipes from child to parent */
 732         if (result != NULL || log_get_max_level() >= LOG_INFO) {
 733                 if (pipe2(outpipe, O_NONBLOCK) != 0) {
 734                         err = log_error_errno(errno, "pipe failed: %m");
 735                         goto out;
 736                 }
 737         }
 738         if (log_get_max_level() >= LOG_INFO) {
 739                 if (pipe2(errpipe, O_NONBLOCK) != 0) {
 740                         err = log_error_errno(errno, "pipe failed: %m");
 741                         goto out;
 742                 }
 743         }
 744
 745         pid = fork();
 746         switch(pid) {
 747         case 0:
 748         {
 749                 char arg[UTIL_PATH_SIZE];
 750                 char *argv[128];
 751                 char program[UTIL_PATH_SIZE];
 752
 753                 /* child closes parent's ends of pipes */
 754                 outpipe[READ_END] = safe_close(outpipe[READ_END]);
 755                 errpipe[READ_END] = safe_close(errpipe[READ_END]);
 756
 757                 strscpy(arg, sizeof(arg), cmd);
 758                 udev_build_argv(event->udev, arg, NULL, argv);
 759
 760                 /* allow programs in /usr/lib/udev/ to be called without the path */
 761                 if (argv[0][0] != '/') {
 762                         strscpyl(program, sizeof(program), UDEVLIBEXECDIR "/", argv[0], NULL);
 763                         argv[0] = program;
 764                 }
 765
 766                 log_debug("starting '%s'", cmd);
 767
 768                 spawn_exec(event, cmd, argv, udev_device_get_properties_envp(event->dev),
 769                            outpipe[WRITE_END], errpipe[WRITE_END]);
 770
 771                 _exit(2);
 772         }
 773         case -1:
 774                 log_error_errno(errno, "fork of '%s' failed: %m", cmd);
 775                 err = -1;
 776                 goto out;
 777         default:
 778                 /* parent closed child's ends of pipes */
 779                 outpipe[WRITE_END] = safe_close(outpipe[WRITE_END]);
 780                 errpipe[WRITE_END] = safe_close(errpipe[WRITE_END]);
 781
 782                 spawn_read(event,
 783                            timeout_usec,
 784                            cmd,
 785                            outpipe[READ_END], errpipe[READ_END],
 786                            result, ressize);
 787
 788                 err = spawn_wait(event, timeout_usec, timeout_warn_usec, cmd, pid, accept_failure);
 789         }
 790
 791 out:
 792         if (outpipe[READ_END] >= 0)
 793                 close(outpipe[READ_END]);
 794         if (outpipe[WRITE_END] >= 0)
 795                 close(outpipe[WRITE_END]);
 796         if (errpipe[READ_END] >= 0)
 797                 close(errpipe[READ_END]);
 798         if (errpipe[WRITE_END] >= 0)
 799                 close(errpipe[WRITE_END]);
 800         return err;
 801 }
 802
 803 static int rename_netif(struct udev_event *event) {
 804         struct udev_device *dev = event->dev;
 805         char name[IFNAMSIZ];
 806         const char *oldname;
 807         int r;
 808
 809         oldname = udev_device_get_sysname(dev);
 810
 811         strscpy(name, IFNAMSIZ, event->name);
 812
 813         r = rtnl_set_link_name(&event->rtnl, udev_device_get_ifindex(dev), name);
 814         if (r < 0)
 815                 return log_error_errno(r, "Error changing net interface name '%s' to '%s': %m", oldname, name);
 816
 817         log_debug("renamed network interface '%s' to '%s'", oldname, name);
 818
 819         return 0;
 820 }
 821
 822 void udev_event_execute_rules(struct udev_event *event,
 823                               usec_t timeout_usec, usec_t timeout_warn_usec,
 824                               struct udev_list *properties_list,
 825                               struct udev_rules *rules) {
 826         struct udev_device *dev = event->dev;
 827
 828         if (udev_device_get_subsystem(dev) == NULL)
 829                 return;
 830
 831         if (streq(udev_device_get_action(dev), "remove")) {
 832                 udev_device_read_db(dev);
 833                 udev_device_tag_index(dev, NULL, false);
 834                 udev_device_delete_db(dev);
 835
 836                 if (major(udev_device_get_devnum(dev)) != 0)
 837                         udev_watch_end(event->udev, dev);
 838
 839                 udev_rules_apply_to_event(rules, event,
 840                                           timeout_usec, timeout_warn_usec,
 841                                           properties_list);
 842
 843                 if (major(udev_device_get_devnum(dev)) != 0)
 844                         udev_node_remove(dev);
 845         } else {
 846                 event->dev_db = udev_device_clone_with_db(dev);
 847                 if (event->dev_db != NULL) {
 848                         /* disable watch during event processing */
 849                         if (major(udev_device_get_devnum(dev)) != 0)
 850                                 udev_watch_end(event->udev, event->dev_db);
 851                 }
 852
 853                 if (major(udev_device_get_devnum(dev)) == 0 &&
 854                     streq(udev_device_get_action(dev), "move"))
 855                         udev_device_copy_properties(dev, event->dev_db);
 856
 857                 udev_rules_apply_to_event(rules, event,
 858                                           timeout_usec, timeout_warn_usec,
 859                                           properties_list);
 860
 861                 /* rename a new network interface, if needed */
 862                 if (udev_device_get_ifindex(dev) > 0 && streq(udev_device_get_action(dev), "add") &&
 863                     event->name != NULL && !streq(event->name, udev_device_get_sysname(dev))) {
 864                         int r;
 865
 866                         r = rename_netif(event);
 867                         if (r < 0)
 868                                 log_warning_errno(r, "could not rename interface '%d' from '%s' to '%s': %m", udev_device_get_ifindex(dev),
 869                                                   udev_device_get_sysname(dev), event->name);
 870                         else {
 871                                 r = udev_device_rename(dev, event->name);
 872                                 if (r < 0)
 873                                         log_warning_errno(r, "renamed interface '%d' from '%s' to '%s', but could not update udev_device: %m",
 874                                                           udev_device_get_ifindex(dev), udev_device_get_sysname(dev), event->name);
 875                                 else
 876                                         log_debug("changed devpath to '%s'", udev_device_get_devpath(dev));
 877                         }
 878                 }
 879
 880                 if (major(udev_device_get_devnum(dev)) > 0) {
 881                         bool apply;
 882
 883                         /* remove/update possible left-over symlinks from old database entry */
 884                         if (event->dev_db != NULL)
 885                                 udev_node_update_old_links(dev, event->dev_db);
 886
 887                         if (!event->owner_set)
 888                                 event->uid = udev_device_get_devnode_uid(dev);
 889
 890                         if (!event->group_set)
 891                                 event->gid = udev_device_get_devnode_gid(dev);
 892
 893                         if (!event->mode_set) {
 894                                 if (udev_device_get_devnode_mode(dev) > 0) {
 895                                         /* kernel supplied value */
 896                                         event->mode = udev_device_get_devnode_mode(dev);
 897                                 } else if (event->gid > 0) {
 898                                         /* default 0660 if a group is assigned */
 899                                         event->mode = 0660;
 900                                 } else {
 901                                         /* default 0600 */
 902                                         event->mode = 0600;
 903                                 }
 904                         }
 905
 906                         apply = streq(udev_device_get_action(dev), "add") || event->owner_set || event->group_set || event->mode_set;
 907                         udev_node_add(dev, apply, event->mode, event->uid, event->gid, &event->seclabel_list);
 908                 }
 909
 910                 /* preserve old, or get new initialization timestamp */
 911                 udev_device_ensure_usec_initialized(event->dev, event->dev_db);
 912
 913                 /* (re)write database file */
 914                 udev_device_tag_index(dev, event->dev_db, true);
 915                 udev_device_update_db(dev);
 916                 udev_device_set_is_initialized(dev);
 917
 918                 event->dev_db = udev_device_unref(event->dev_db);
 919         }
 920 }
 921
 922 void udev_event_execute_run(struct udev_event *event, usec_t timeout_usec, usec_t timeout_warn_usec) {
 923         struct udev_list_entry *list_entry;
 924
 925         udev_list_entry_foreach(list_entry, udev_list_get_entry(&event->run_list)) {
 926                 char command[UTIL_PATH_SIZE];
 927                 const char *cmd = udev_list_entry_get_name(list_entry);
 928                 enum udev_builtin_cmd builtin_cmd = udev_list_entry_get_num(list_entry);
 929
 930                 udev_event_apply_format(event, cmd, command, sizeof(command));
 931
 932                 if (builtin_cmd < UDEV_BUILTIN_MAX)
 933                         udev_builtin_run(event->dev, builtin_cmd, command, false);
 934                 else {
 935                         if (event->exec_delay > 0) {
 936                                 log_debug("delay execution of '%s'", command);
 937                                 sleep(event->exec_delay);
 938                         }
 939
 940                         udev_event_spawn(event, timeout_usec, timeout_warn_usec, false, command, NULL, 0);
 941                 }
 942         }
 943 }