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 "event-util.h"
  35 #include "fd-util.h"
  36 #include "formats-util.h"
  37 #include "netlink-util.h"
  38 #include "process-util.h"
  39 #include "signal-util.h"
  40 #include "string-util.h"
  41 #include "udev.h"
  42
  43 typedef struct Spawn {
  44         const char *cmd;
  45         pid_t pid;
  46         usec_t timeout_warn;
  47         usec_t timeout;
  48         bool accept_failure;
  49 } Spawn;
  50
  51 struct udev_event *udev_event_new(struct udev_device *dev) {
  52         struct udev *udev = udev_device_get_udev(dev);
  53         struct udev_event *event;
  54
  55         event = new0(struct udev_event, 1);
  56         if (event == NULL)
  57                 return NULL;
  58         event->dev = dev;
  59         event->udev = udev;
  60         udev_list_init(udev, &event->run_list, false);
  61         udev_list_init(udev, &event->seclabel_list, false);
  62         event->birth_usec = clock_boottime_or_monotonic();
  63         return event;
  64 }
  65
  66 void udev_event_unref(struct udev_event *event) {
  67         if (event == NULL)
  68                 return;
  69         sd_netlink_unref(event->rtnl);
  70         udev_list_cleanup(&event->run_list);
  71         udev_list_cleanup(&event->seclabel_list);
  72         free(event->program_result);
  73         free(event->name);
  74         free(event);
  75 }
  76
  77 size_t udev_event_apply_format(struct udev_event *event, const char *src, char *dest, size_t size) {
  78         struct udev_device *dev = event->dev;
  79         enum subst_type {
  80                 SUBST_UNKNOWN,
  81                 SUBST_DEVNODE,
  82                 SUBST_ATTR,
  83                 SUBST_ENV,
  84                 SUBST_KERNEL,
  85                 SUBST_KERNEL_NUMBER,
  86                 SUBST_DRIVER,
  87                 SUBST_DEVPATH,
  88                 SUBST_ID,
  89                 SUBST_MAJOR,
  90                 SUBST_MINOR,
  91                 SUBST_RESULT,
  92                 SUBST_PARENT,
  93                 SUBST_NAME,
  94                 SUBST_LINKS,
  95                 SUBST_ROOT,
  96                 SUBST_SYS,
  97         };
  98         static const struct subst_map {
  99                 const char *name;
 100                 const char fmt;
 101                 enum subst_type type;
 102         } map[] = {
 103                 { .name = "devnode",  .fmt = 'N', .type = SUBST_DEVNODE },
 104                 { .name = "tempnode", .fmt = 'N', .type = SUBST_DEVNODE },
 105                 { .name = "attr",     .fmt = 's', .type = SUBST_ATTR },
 106                 { .name = "sysfs",    .fmt = 's', .type = SUBST_ATTR },
 107                 { .name = "env",      .fmt = 'E', .type = SUBST_ENV },
 108                 { .name = "kernel",   .fmt = 'k', .type = SUBST_KERNEL },
 109                 { .name = "number",   .fmt = 'n', .type = SUBST_KERNEL_NUMBER },
 110                 { .name = "driver",   .fmt = 'd', .type = SUBST_DRIVER },
 111                 { .name = "devpath",  .fmt = 'p', .type = SUBST_DEVPATH },
 112                 { .name = "id",       .fmt = 'b', .type = SUBST_ID },
 113                 { .name = "major",    .fmt = 'M', .type = SUBST_MAJOR },
 114                 { .name = "minor",    .fmt = 'm', .type = SUBST_MINOR },
 115                 { .name = "result",   .fmt = 'c', .type = SUBST_RESULT },
 116                 { .name = "parent",   .fmt = 'P', .type = SUBST_PARENT },
 117                 { .name = "name",     .fmt = 'D', .type = SUBST_NAME },
 118                 { .name = "links",    .fmt = 'L', .type = SUBST_LINKS },
 119                 { .name = "root",     .fmt = 'r', .type = SUBST_ROOT },
 120                 { .name = "sys",      .fmt = 'S', .type = SUBST_SYS },
 121         };
 122         const char *from;
 123         char *s;
 124         size_t l;
 125
 126         assert(dev);
 127
 128         from = src;
 129         s = dest;
 130         l = size;
 131
 132         for (;;) {
 133                 enum subst_type type = SUBST_UNKNOWN;
 134                 char attrbuf[UTIL_PATH_SIZE];
 135                 char *attr = NULL;
 136
 137                 while (from[0] != '\0') {
 138                         if (from[0] == '$') {
 139                                 /* substitute named variable */
 140                                 unsigned int i;
 141
 142                                 if (from[1] == '$') {
 143                                         from++;
 144                                         goto copy;
 145                                 }
 146
 147                                 for (i = 0; i < ELEMENTSOF(map); i++) {
 148                                         if (startswith(&from[1], map[i].name)) {
 149                                                 type = map[i].type;
 150                                                 from += strlen(map[i].name)+1;
 151                                                 goto subst;
 152                                         }
 153                                 }
 154                         } else if (from[0] == '%') {
 155                                 /* substitute format char */
 156                                 unsigned int i;
 157
 158                                 if (from[1] == '%') {
 159                                         from++;
 160                                         goto copy;
 161                                 }
 162
 163                                 for (i = 0; i < ELEMENTSOF(map); i++) {
 164                                         if (from[1] == map[i].fmt) {
 165                                                 type = map[i].type;
 166                                                 from += 2;
 167                                                 goto subst;
 168                                         }
 169                                 }
 170                         }
 171 copy:
 172                         /* copy char */
 173                         if (l == 0)
 174                                 goto out;
 175                         s[0] = from[0];
 176                         from++;
 177                         s++;
 178                         l--;
 179                 }
 180
 181                 goto out;
 182 subst:
 183                 /* extract possible $format{attr} */
 184                 if (from[0] == '{') {
 185                         unsigned int i;
 186
 187                         from++;
 188                         for (i = 0; from[i] != '}'; i++) {
 189                                 if (from[i] == '\0') {
 190                                         log_error("missing closing brace for format '%s'", src);
 191                                         goto out;
 192                                 }
 193                         }
 194                         if (i >= sizeof(attrbuf))
 195                                 goto out;
 196                         memcpy(attrbuf, from, i);
 197                         attrbuf[i] = '\0';
 198                         from += i+1;
 199                         attr = attrbuf;
 200                 } else {
 201                         attr = NULL;
 202                 }
 203
 204                 switch (type) {
 205                 case SUBST_DEVPATH:
 206                         l = strpcpy(&s, l, udev_device_get_devpath(dev));
 207                         break;
 208                 case SUBST_KERNEL:
 209                         l = strpcpy(&s, l, udev_device_get_sysname(dev));
 210                         break;
 211                 case SUBST_KERNEL_NUMBER:
 212                         if (udev_device_get_sysnum(dev) == NULL)
 213                                 break;
 214                         l = strpcpy(&s, l, udev_device_get_sysnum(dev));
 215                         break;
 216                 case SUBST_ID:
 217                         if (event->dev_parent == NULL)
 218                                 break;
 219                         l = strpcpy(&s, l, udev_device_get_sysname(event->dev_parent));
 220                         break;
 221                 case SUBST_DRIVER: {
 222                         const char *driver;
 223
 224                         if (event->dev_parent == NULL)
 225                                 break;
 226
 227                         driver = udev_device_get_driver(event->dev_parent);
 228                         if (driver == NULL)
 229                                 break;
 230                         l = strpcpy(&s, l, driver);
 231                         break;
 232                 }
 233                 case SUBST_MAJOR: {
 234                         char num[UTIL_PATH_SIZE];
 235
 236                         sprintf(num, "%u", major(udev_device_get_devnum(dev)));
 237                         l = strpcpy(&s, l, num);
 238                         break;
 239                 }
 240                 case SUBST_MINOR: {
 241                         char num[UTIL_PATH_SIZE];
 242
 243                         sprintf(num, "%u", minor(udev_device_get_devnum(dev)));
 244                         l = strpcpy(&s, l, num);
 245                         break;
 246                 }
 247                 case SUBST_RESULT: {
 248                         char *rest;
 249                         int i;
 250
 251                         if (event->program_result == NULL)
 252                                 break;
 253                         /* get part part of the result string */
 254                         i = 0;
 255                         if (attr != NULL)
 256                                 i = strtoul(attr, &rest, 10);
 257                         if (i > 0) {
 258                                 char result[UTIL_PATH_SIZE];
 259                                 char tmp[UTIL_PATH_SIZE];
 260                                 char *cpos;
 261
 262                                 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                                         if (cpos[0] == '\0')
 270                                                 break;
 271                                 }
 272                                 if (i > 0) {
 273                                         log_error("requested part of result string not found");
 274                                         break;
 275                                 }
 276                                 strscpy(tmp, sizeof(tmp), cpos);
 277                                 /* %{2+}c copies the whole string from the second part on */
 278                                 if (rest[0] != '+') {
 279                                         cpos = strchr(tmp, ' ');
 280                                         if (cpos)
 281                                                 cpos[0] = '\0';
 282                                 }
 283                                 l = strpcpy(&s, l, tmp);
 284                         } else {
 285                                 l = strpcpy(&s, l, 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                                 log_error("missing file parameter for attr");
 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                                 strscpy(vbuf, sizeof(vbuf), value);
 318                         len = strlen(vbuf);
 319                         while (len > 0 && isspace(vbuf[--len]))
 320                                 vbuf[len] = '\0';
 321                         count = util_replace_chars(vbuf, UDEV_ALLOWED_CHARS_INPUT);
 322                         if (count > 0)
 323                                 log_debug("%i character(s) replaced" , count);
 324                         l = strpcpy(&s, l, vbuf);
 325                         break;
 326                 }
 327                 case SUBST_PARENT: {
 328                         struct udev_device *dev_parent;
 329                         const char *devnode;
 330
 331                         dev_parent = udev_device_get_parent(event->dev);
 332                         if (dev_parent == NULL)
 333                                 break;
 334                         devnode = udev_device_get_devnode(dev_parent);
 335                         if (devnode != NULL)
 336                                 l = strpcpy(&s, l, devnode + strlen("/dev/"));
 337                         break;
 338                 }
 339                 case SUBST_DEVNODE:
 340                         if (udev_device_get_devnode(dev) != NULL)
 341                                 l = strpcpy(&s, l, udev_device_get_devnode(dev));
 342                         break;
 343                 case SUBST_NAME:
 344                         if (event->name != NULL)
 345                                 l = strpcpy(&s, l, event->name);
 346                         else if (udev_device_get_devnode(dev) != NULL)
 347                                 l = strpcpy(&s, l, udev_device_get_devnode(dev) + strlen("/dev/"));
 348                         else
 349                                 l = strpcpy(&s, l, udev_device_get_sysname(dev));
 350                         break;
 351                 case SUBST_LINKS: {
 352                         struct udev_list_entry *list_entry;
 353
 354                         list_entry = udev_device_get_devlinks_list_entry(dev);
 355                         if (list_entry == NULL)
 356                                 break;
 357                         l = strpcpy(&s, l, udev_list_entry_get_name(list_entry) + strlen("/dev/"));
 358                         udev_list_entry_foreach(list_entry, udev_list_entry_get_next(list_entry))
 359                                 l = strpcpyl(&s, l, " ", udev_list_entry_get_name(list_entry) + strlen("/dev/"), NULL);
 360                         break;
 361                 }
 362                 case SUBST_ROOT:
 363                         l = strpcpy(&s, l, "/dev");
 364                         break;
 365                 case SUBST_SYS:
 366                         l = strpcpy(&s, l, "/sys");
 367                         break;
 368                 case SUBST_ENV:
 369                         if (attr == NULL) {
 370                                 break;
 371                         } else {
 372                                 const char *value;
 373
 374                                 value = udev_device_get_property_value(event->dev, attr);
 375                                 if (value == NULL)
 376                                         break;
 377                                 l = strpcpy(&s, l, value);
 378                                 break;
 379                         }
 380                 default:
 381                         log_error("unknown substitution type=%i", type);
 382                         break;
 383                 }
 384         }
 385
 386 out:
 387         s[0] = '\0';
 388         return l;
 389 }
 390
 391 static int spawn_exec(struct udev_event *event,
 392                       const char *cmd, char *const argv[], char **envp,
 393                       int fd_stdout, int fd_stderr) {
 394         _cleanup_close_ int fd = -1;
 395         int r;
 396
 397         /* discard child output or connect to pipe */
 398         fd = open("/dev/null", O_RDWR);
 399         if (fd >= 0) {
 400                 r = dup2(fd, STDIN_FILENO);
 401                 if (r < 0)
 402                         log_warning_errno(errno, "redirecting stdin failed: %m");
 403
 404                 if (fd_stdout < 0) {
 405                         r = dup2(fd, STDOUT_FILENO);
 406                         if (r < 0)
 407                                 log_warning_errno(errno, "redirecting stdout failed: %m");
 408                 }
 409
 410                 if (fd_stderr < 0) {
 411                         r = dup2(fd, STDERR_FILENO);
 412                         if (r < 0)
 413                                 log_warning_errno(errno, "redirecting stderr failed: %m");
 414                 }
 415         } else
 416                 log_warning_errno(errno, "open /dev/null failed: %m");
 417
 418         /* connect pipes to std{out,err} */
 419         if (fd_stdout >= 0) {
 420                 r = dup2(fd_stdout, STDOUT_FILENO);
 421                 if (r < 0)
 422                         log_warning_errno(errno, "redirecting stdout failed: %m");
 423
 424                 fd_stdout = safe_close(fd_stdout);
 425         }
 426
 427         if (fd_stderr >= 0) {
 428                 r = dup2(fd_stderr, STDERR_FILENO);
 429                 if (r < 0)
 430                         log_warning_errno(errno, "redirecting stdout failed: %m");
 431
 432                 fd_stderr = safe_close(fd_stderr);
 433         }
 434
 435         /* terminate child in case parent goes away */
 436         prctl(PR_SET_PDEATHSIG, SIGTERM);
 437
 438         /* restore sigmask before exec */
 439         (void) reset_signal_mask();
 440
 441         execve(argv[0], argv, envp);
 442
 443         /* exec failed */
 444         log_error_errno(errno, "failed to execute '%s' '%s': %m", argv[0], cmd);
 445
 446         return -errno;
 447 }
 448
 449 static void spawn_read(struct udev_event *event,
 450                        usec_t timeout_usec,
 451                        const char *cmd,
 452                        int fd_stdout, int fd_stderr,
 453                        char *result, size_t ressize) {
 454         _cleanup_close_ int fd_ep = -1;
 455         struct epoll_event ep_outpipe = {
 456                 .events = EPOLLIN,
 457                 .data.ptr = &fd_stdout,
 458         };
 459         struct epoll_event ep_errpipe = {
 460                 .events = EPOLLIN,
 461                 .data.ptr = &fd_stderr,
 462         };
 463         size_t respos = 0;
 464         int r;
 465
 466         /* read from child if requested */
 467         if (fd_stdout < 0 && fd_stderr < 0)
 468                 return;
 469
 470         fd_ep = epoll_create1(EPOLL_CLOEXEC);
 471         if (fd_ep < 0) {
 472                 log_error_errno(errno, "error creating epoll fd: %m");
 473                 return;
 474         }
 475
 476         if (fd_stdout >= 0) {
 477                 r = epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_stdout, &ep_outpipe);
 478                 if (r < 0) {
 479                         log_error_errno(errno, "fail to add stdout fd to epoll: %m");
 480                         return;
 481                 }
 482         }
 483
 484         if (fd_stderr >= 0) {
 485                 r = epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_stderr, &ep_errpipe);
 486                 if (r < 0) {
 487                         log_error_errno(errno, "fail to add stderr fd to epoll: %m");
 488                         return;
 489                 }
 490         }
 491
 492         /* read child output */
 493         while (fd_stdout >= 0 || fd_stderr >= 0) {
 494                 int timeout;
 495                 int fdcount;
 496                 struct epoll_event ev[4];
 497                 int i;
 498
 499                 if (timeout_usec > 0) {
 500                         usec_t age_usec;
 501
 502                         age_usec = clock_boottime_or_monotonic() - event->birth_usec;
 503                         if (age_usec >= timeout_usec) {
 504                                 log_error("timeout '%s'", cmd);
 505                                 return;
 506                         }
 507                         timeout = ((timeout_usec - age_usec) / USEC_PER_MSEC) + MSEC_PER_SEC;
 508                 } else {
 509                         timeout = -1;
 510                 }
 511
 512                 fdcount = epoll_wait(fd_ep, ev, ELEMENTSOF(ev), timeout);
 513                 if (fdcount < 0) {
 514                         if (errno == EINTR)
 515                                 continue;
 516                         log_error_errno(errno, "failed to poll: %m");
 517                         return;
 518                 } else if (fdcount == 0) {
 519                         log_error("timeout '%s'", cmd);
 520                         return;
 521                 }
 522
 523                 for (i = 0; i < fdcount; i++) {
 524                         int *fd = (int *)ev[i].data.ptr;
 525
 526                         if (*fd < 0)
 527                                 continue;
 528
 529                         if (ev[i].events & EPOLLIN) {
 530                                 ssize_t count;
 531                                 char buf[4096];
 532
 533                                 count = read(*fd, buf, sizeof(buf)-1);
 534                                 if (count <= 0)
 535                                         continue;
 536                                 buf[count] = '\0';
 537
 538                                 /* store stdout result */
 539                                 if (result != NULL && *fd == fd_stdout) {
 540                                         if (respos + count < ressize) {
 541                                                 memcpy(&result[respos], buf, count);
 542                                                 respos += count;
 543                                         } else {
 544                                                 log_error("'%s' ressize %zu too short", cmd, ressize);
 545                                         }
 546                                 }
 547
 548                                 /* log debug output only if we watch stderr */
 549                                 if (fd_stderr >= 0) {
 550                                         char *pos;
 551                                         char *line;
 552
 553                                         pos = buf;
 554                                         while ((line = strsep(&pos, "\n"))) {
 555                                                 if (pos != NULL || line[0] != '\0')
 556                                                         log_debug("'%s'(%s) '%s'", cmd, *fd == fd_stdout ? "out" : "err" , line);
 557                                         }
 558                                 }
 559                         } else if (ev[i].events & EPOLLHUP) {
 560                                 r = epoll_ctl(fd_ep, EPOLL_CTL_DEL, *fd, NULL);
 561                                 if (r < 0) {
 562                                         log_error_errno(errno, "failed to remove fd from epoll: %m");
 563                                         return;
 564                                 }
 565                                 *fd = -1;
 566                         }
 567                 }
 568         }
 569
 570         /* return the child's stdout string */
 571         if (result != NULL)
 572                 result[respos] = '\0';
 573 }
 574
 575 static int on_spawn_timeout(sd_event_source *s, uint64_t usec, void *userdata) {
 576         Spawn *spawn = userdata;
 577         char timeout[FORMAT_TIMESTAMP_RELATIVE_MAX];
 578
 579         assert(spawn);
 580
 581         kill_and_sigcont(spawn->pid, SIGKILL);
 582
 583         log_error("spawned process '%s' ["PID_FMT"] timed out after %s, killing", spawn->cmd, spawn->pid,
 584                   format_timestamp_relative(timeout, sizeof(timeout), spawn->timeout));
 585
 586         return 1;
 587 }
 588
 589 static int on_spawn_timeout_warning(sd_event_source *s, uint64_t usec, void *userdata) {
 590         Spawn *spawn = userdata;
 591         char timeout[FORMAT_TIMESTAMP_RELATIVE_MAX];
 592
 593         assert(spawn);
 594
 595         log_warning("spawned process '%s' ["PID_FMT"] is taking longer than %s to complete", spawn->cmd, spawn->pid,
 596                     format_timestamp_relative(timeout, sizeof(timeout), spawn->timeout));
 597
 598         return 1;
 599 }
 600
 601 static int on_spawn_sigchld(sd_event_source *s, const siginfo_t *si, void *userdata) {
 602         Spawn *spawn = userdata;
 603
 604         assert(spawn);
 605
 606         switch (si->si_code) {
 607         case CLD_EXITED:
 608                 if (si->si_status == 0) {
 609                         log_debug("Process '%s' succeeded.", spawn->cmd);
 610                         sd_event_exit(sd_event_source_get_event(s), 0);
 611
 612                         return 1;
 613                 } else if (spawn->accept_failure)
 614                         log_debug("Process '%s' failed with exit code %i.", spawn->cmd, si->si_status);
 615                 else
 616                         log_warning("Process '%s' failed with exit code %i.", spawn->cmd, si->si_status);
 617
 618                 break;
 619         case CLD_KILLED:
 620         case CLD_DUMPED:
 621                 log_warning("Process '%s' terminated by signal %s.", spawn->cmd, signal_to_string(si->si_status));
 622
 623                 break;
 624         default:
 625                 log_error("Process '%s' failed due to unknown reason.", spawn->cmd);
 626         }
 627
 628         sd_event_exit(sd_event_source_get_event(s), -EIO);
 629
 630         return 1;
 631 }
 632
 633 static int spawn_wait(struct udev_event *event,
 634                       usec_t timeout_usec,
 635                       usec_t timeout_warn_usec,
 636                       const char *cmd, pid_t pid,
 637                       bool accept_failure) {
 638         Spawn spawn = {
 639                 .cmd = cmd,
 640                 .pid = pid,
 641                 .accept_failure = accept_failure,
 642         };
 643         _cleanup_event_unref_ sd_event *e = NULL;
 644         int r, ret;
 645
 646         r = sd_event_new(&e);
 647         if (r < 0)
 648                 return r;
 649
 650         if (timeout_usec > 0) {
 651                 usec_t usec, age_usec;
 652
 653                 usec = now(clock_boottime_or_monotonic());
 654                 age_usec = usec - event->birth_usec;
 655                 if (age_usec < timeout_usec) {
 656                         if (timeout_warn_usec > 0 && timeout_warn_usec < timeout_usec && age_usec < timeout_warn_usec) {
 657                                 spawn.timeout_warn = timeout_warn_usec - age_usec;
 658
 659                                 r = sd_event_add_time(e, NULL, clock_boottime_or_monotonic(),
 660                                                       usec + spawn.timeout_warn, USEC_PER_SEC,
 661                                                       on_spawn_timeout_warning, &spawn);
 662                                 if (r < 0)
 663                                         return r;
 664                         }
 665
 666                         spawn.timeout = timeout_usec - age_usec;
 667
 668                         r = sd_event_add_time(e, NULL, clock_boottime_or_monotonic(),
 669                                               usec + spawn.timeout, USEC_PER_SEC, on_spawn_timeout, &spawn);
 670                         if (r < 0)
 671                                 return r;
 672                 }
 673         }
 674
 675         r = sd_event_add_child(e, NULL, pid, WEXITED, on_spawn_sigchld, &spawn);
 676         if (r < 0)
 677                 return r;
 678
 679         r = sd_event_loop(e);
 680         if (r < 0)
 681                 return r;
 682
 683         r = sd_event_get_exit_code(e, &ret);
 684         if (r < 0)
 685                 return r;
 686
 687         return ret;
 688 }
 689
 690 int udev_build_argv(struct udev *udev, char *cmd, int *argc, char *argv[]) {
 691         int i = 0;
 692         char *pos;
 693
 694         if (strchr(cmd, ' ') == NULL) {
 695                 argv[i++] = cmd;
 696                 goto out;
 697         }
 698
 699         pos = cmd;
 700         while (pos != NULL && pos[0] != '\0') {
 701                 if (pos[0] == '\'') {
 702                         /* do not separate quotes */
 703                         pos++;
 704                         argv[i] = strsep(&pos, "\'");
 705                         if (pos != NULL)
 706                                 while (pos[0] == ' ')
 707                                         pos++;
 708                 } else {
 709                         argv[i] = strsep(&pos, " ");
 710                         if (pos != NULL)
 711                                 while (pos[0] == ' ')
 712                                         pos++;
 713                 }
 714                 i++;
 715         }
 716 out:
 717         argv[i] = NULL;
 718         if (argc)
 719                 *argc = i;
 720         return 0;
 721 }
 722
 723 int udev_event_spawn(struct udev_event *event,
 724                      usec_t timeout_usec,
 725                      usec_t timeout_warn_usec,
 726                      bool accept_failure,
 727                      const char *cmd,
 728                      char *result, size_t ressize) {
 729         int outpipe[2] = {-1, -1};
 730         int errpipe[2] = {-1, -1};
 731         pid_t pid;
 732         int err = 0;
 733
 734         /* pipes from child to parent */
 735         if (result != NULL || log_get_max_level() >= LOG_INFO) {
 736                 if (pipe2(outpipe, O_NONBLOCK) != 0) {
 737                         err = log_error_errno(errno, "pipe failed: %m");
 738                         goto out;
 739                 }
 740         }
 741         if (log_get_max_level() >= LOG_INFO) {
 742                 if (pipe2(errpipe, O_NONBLOCK) != 0) {
 743                         err = log_error_errno(errno, "pipe failed: %m");
 744                         goto out;
 745                 }
 746         }
 747
 748         pid = fork();
 749         switch(pid) {
 750         case 0:
 751         {
 752                 char arg[UTIL_PATH_SIZE];
 753                 char *argv[128];
 754                 char program[UTIL_PATH_SIZE];
 755
 756                 /* child closes parent's ends of pipes */
 757                 outpipe[READ_END] = safe_close(outpipe[READ_END]);
 758                 errpipe[READ_END] = safe_close(errpipe[READ_END]);
 759
 760                 strscpy(arg, sizeof(arg), cmd);
 761                 udev_build_argv(event->udev, arg, NULL, argv);
 762
 763                 /* allow programs in /usr/lib/udev/ to be called without the path */
 764                 if (argv[0][0] != '/') {
 765                         strscpyl(program, sizeof(program), UDEVLIBEXECDIR "/", argv[0], NULL);
 766                         argv[0] = program;
 767                 }
 768
 769                 log_debug("starting '%s'", cmd);
 770
 771                 spawn_exec(event, cmd, argv, udev_device_get_properties_envp(event->dev),
 772                            outpipe[WRITE_END], errpipe[WRITE_END]);
 773
 774                 _exit(2);
 775         }
 776         case -1:
 777                 log_error_errno(errno, "fork of '%s' failed: %m", cmd);
 778                 err = -1;
 779                 goto out;
 780         default:
 781                 /* parent closed child's ends of pipes */
 782                 outpipe[WRITE_END] = safe_close(outpipe[WRITE_END]);
 783                 errpipe[WRITE_END] = safe_close(errpipe[WRITE_END]);
 784
 785                 spawn_read(event,
 786                            timeout_usec,
 787                            cmd,
 788                            outpipe[READ_END], errpipe[READ_END],
 789                            result, ressize);
 790
 791                 err = spawn_wait(event, timeout_usec, timeout_warn_usec, cmd, pid, accept_failure);
 792         }
 793
 794 out:
 795         if (outpipe[READ_END] >= 0)
 796                 close(outpipe[READ_END]);
 797         if (outpipe[WRITE_END] >= 0)
 798                 close(outpipe[WRITE_END]);
 799         if (errpipe[READ_END] >= 0)
 800                 close(errpipe[READ_END]);
 801         if (errpipe[WRITE_END] >= 0)
 802                 close(errpipe[WRITE_END]);
 803         return err;
 804 }
 805
 806 static int rename_netif(struct udev_event *event) {
 807         struct udev_device *dev = event->dev;
 808         char name[IFNAMSIZ];
 809         const char *oldname;
 810         int r;
 811
 812         oldname = udev_device_get_sysname(dev);
 813
 814         strscpy(name, IFNAMSIZ, event->name);
 815
 816         r = rtnl_set_link_name(&event->rtnl, udev_device_get_ifindex(dev), name);
 817         if (r < 0)
 818                 return log_error_errno(r, "Error changing net interface name '%s' to '%s': %m", oldname, name);
 819
 820         log_debug("renamed network interface '%s' to '%s'", oldname, name);
 821
 822         return 0;
 823 }
 824
 825 void udev_event_execute_rules(struct udev_event *event,
 826                               usec_t timeout_usec, usec_t timeout_warn_usec,
 827                               struct udev_list *properties_list,
 828                               struct udev_rules *rules) {
 829         struct udev_device *dev = event->dev;
 830
 831         if (udev_device_get_subsystem(dev) == NULL)
 832                 return;
 833
 834         if (streq(udev_device_get_action(dev), "remove")) {
 835                 udev_device_read_db(dev);
 836                 udev_device_tag_index(dev, NULL, false);
 837                 udev_device_delete_db(dev);
 838
 839                 if (major(udev_device_get_devnum(dev)) != 0)
 840                         udev_watch_end(event->udev, dev);
 841
 842                 udev_rules_apply_to_event(rules, event,
 843                                           timeout_usec, timeout_warn_usec,
 844                                           properties_list);
 845
 846                 if (major(udev_device_get_devnum(dev)) != 0)
 847                         udev_node_remove(dev);
 848         } else {
 849                 event->dev_db = udev_device_clone_with_db(dev);
 850                 if (event->dev_db != NULL) {
 851                         /* disable watch during event processing */
 852                         if (major(udev_device_get_devnum(dev)) != 0)
 853                                 udev_watch_end(event->udev, event->dev_db);
 854                 }
 855
 856                 if (major(udev_device_get_devnum(dev)) == 0 &&
 857                     streq(udev_device_get_action(dev), "move"))
 858                         udev_device_copy_properties(dev, event->dev_db);
 859
 860                 udev_rules_apply_to_event(rules, event,
 861                                           timeout_usec, timeout_warn_usec,
 862                                           properties_list);
 863
 864                 /* rename a new network interface, if needed */
 865                 if (udev_device_get_ifindex(dev) > 0 && streq(udev_device_get_action(dev), "add") &&
 866                     event->name != NULL && !streq(event->name, udev_device_get_sysname(dev))) {
 867                         int r;
 868
 869                         r = rename_netif(event);
 870                         if (r < 0)
 871                                 log_warning_errno(r, "could not rename interface '%d' from '%s' to '%s': %m", udev_device_get_ifindex(dev),
 872                                                   udev_device_get_sysname(dev), event->name);
 873                         else {
 874                                 r = udev_device_rename(dev, event->name);
 875                                 if (r < 0)
 876                                         log_warning_errno(r, "renamed interface '%d' from '%s' to '%s', but could not update udev_device: %m",
 877                                                           udev_device_get_ifindex(dev), udev_device_get_sysname(dev), event->name);
 878                                 else
 879                                         log_debug("changed devpath to '%s'", udev_device_get_devpath(dev));
 880                         }
 881                 }
 882
 883                 if (major(udev_device_get_devnum(dev)) > 0) {
 884                         bool apply;
 885
 886                         /* remove/update possible left-over symlinks from old database entry */
 887                         if (event->dev_db != NULL)
 888                                 udev_node_update_old_links(dev, event->dev_db);
 889
 890                         if (!event->owner_set)
 891                                 event->uid = udev_device_get_devnode_uid(dev);
 892
 893                         if (!event->group_set)
 894                                 event->gid = udev_device_get_devnode_gid(dev);
 895
 896                         if (!event->mode_set) {
 897                                 if (udev_device_get_devnode_mode(dev) > 0) {
 898                                         /* kernel supplied value */
 899                                         event->mode = udev_device_get_devnode_mode(dev);
 900                                 } else if (event->gid > 0) {
 901                                         /* default 0660 if a group is assigned */
 902                                         event->mode = 0660;
 903                                 } else {
 904                                         /* default 0600 */
 905                                         event->mode = 0600;
 906                                 }
 907                         }
 908
 909                         apply = streq(udev_device_get_action(dev), "add") || event->owner_set || event->group_set || event->mode_set;
 910                         udev_node_add(dev, apply, event->mode, event->uid, event->gid, &event->seclabel_list);
 911                 }
 912
 913                 /* preserve old, or get new initialization timestamp */
 914                 udev_device_ensure_usec_initialized(event->dev, event->dev_db);
 915
 916                 /* (re)write database file */
 917                 udev_device_tag_index(dev, event->dev_db, true);
 918                 udev_device_update_db(dev);
 919                 udev_device_set_is_initialized(dev);
 920
 921                 event->dev_db = udev_device_unref(event->dev_db);
 922         }
 923 }
 924
 925 void udev_event_execute_run(struct udev_event *event, usec_t timeout_usec, usec_t timeout_warn_usec) {
 926         struct udev_list_entry *list_entry;
 927
 928         udev_list_entry_foreach(list_entry, udev_list_get_entry(&event->run_list)) {
 929                 char command[UTIL_PATH_SIZE];
 930                 const char *cmd = udev_list_entry_get_name(list_entry);
 931                 enum udev_builtin_cmd builtin_cmd = udev_list_entry_get_num(list_entry);
 932
 933                 udev_event_apply_format(event, cmd, command, sizeof(command));
 934
 935                 if (builtin_cmd < UDEV_BUILTIN_MAX)
 936                         udev_builtin_run(event->dev, builtin_cmd, command, false);
 937                 else {
 938                         if (event->exec_delay > 0) {
 939                                 log_debug("delay execution of '%s'", command);
 940                                 sleep(event->exec_delay);
 941                         }
 942
 943                         udev_event_spawn(event, timeout_usec, timeout_warn_usec, false, command, NULL, 0);
 944                 }
 945         }
 946 }