src/udev/udev-event.c

   1 /* SPDX-License-Identifier: GPL-2.0+ */
   2 /*
   3  * Copyright (C) 2003-2013 Kay Sievers <kay@vrfy.org>
   4  *
   5  * This program is free software: you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation, either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19 #include <ctype.h>
  20 #include <errno.h>
  21 #include <fcntl.h>
  22 #include <net/if.h>
  23 #include <poll.h>
  24 #include <stddef.h>
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #include <string.h>
  28 #include <sys/epoll.h>
  29 #include <sys/prctl.h>
  30 #include <sys/signalfd.h>
  31 #include <sys/wait.h>
  32 #include <unistd.h>
  33
  34 #include "alloc-util.h"
  35 #include "fd-util.h"
  36 #include "format-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 = now(CLOCK_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 enum subst_type {
  78         SUBST_UNKNOWN,
  79         SUBST_DEVNODE,
  80         SUBST_ATTR,
  81         SUBST_ENV,
  82         SUBST_KERNEL,
  83         SUBST_KERNEL_NUMBER,
  84         SUBST_DRIVER,
  85         SUBST_DEVPATH,
  86         SUBST_ID,
  87         SUBST_MAJOR,
  88         SUBST_MINOR,
  89         SUBST_RESULT,
  90         SUBST_PARENT,
  91         SUBST_NAME,
  92         SUBST_LINKS,
  93         SUBST_ROOT,
  94         SUBST_SYS,
  95 };
  96
  97 static size_t subst_format_var(struct udev_event *event, struct udev_device *dev,
  98                                enum subst_type type, char *attr,
  99                                char *dest, size_t l) {
 100         char *s = dest;
 101
 102         switch (type) {
 103         case SUBST_DEVPATH:
 104                 l = strpcpy(&s, l, udev_device_get_devpath(dev));
 105                 break;
 106         case SUBST_KERNEL:
 107                 l = strpcpy(&s, l, udev_device_get_sysname(dev));
 108                 break;
 109         case SUBST_KERNEL_NUMBER:
 110                 if (udev_device_get_sysnum(dev) == NULL)
 111                         break;
 112                 l = strpcpy(&s, l, udev_device_get_sysnum(dev));
 113                 break;
 114         case SUBST_ID:
 115                 if (event->dev_parent == NULL)
 116                         break;
 117                 l = strpcpy(&s, l, udev_device_get_sysname(event->dev_parent));
 118                 break;
 119         case SUBST_DRIVER: {
 120                 const char *driver;
 121
 122                 if (event->dev_parent == NULL)
 123                         break;
 124
 125                 driver = udev_device_get_driver(event->dev_parent);
 126                 if (driver == NULL)
 127                         break;
 128                 l = strpcpy(&s, l, driver);
 129                 break;
 130         }
 131         case SUBST_MAJOR: {
 132                 char num[UTIL_PATH_SIZE];
 133
 134                 sprintf(num, "%u", major(udev_device_get_devnum(dev)));
 135                 l = strpcpy(&s, l, num);
 136                 break;
 137         }
 138         case SUBST_MINOR: {
 139                 char num[UTIL_PATH_SIZE];
 140
 141                 sprintf(num, "%u", minor(udev_device_get_devnum(dev)));
 142                 l = strpcpy(&s, l, num);
 143                 break;
 144         }
 145         case SUBST_RESULT: {
 146                 char *rest;
 147                 int i;
 148
 149                 if (event->program_result == NULL)
 150                         break;
 151                 /* get part of the result string */
 152                 i = 0;
 153                 if (attr != NULL)
 154                         i = strtoul(attr, &rest, 10);
 155                 if (i > 0) {
 156                         char result[UTIL_PATH_SIZE];
 157                         char tmp[UTIL_PATH_SIZE];
 158                         char *cpos;
 159
 160                         strscpy(result, sizeof(result), event->program_result);
 161                         cpos = result;
 162                         while (--i) {
 163                                 while (cpos[0] != '\0' && !isspace(cpos[0]))
 164                                         cpos++;
 165                                 while (isspace(cpos[0]))
 166                                         cpos++;
 167                                 if (cpos[0] == '\0')
 168                                         break;
 169                         }
 170                         if (i > 0) {
 171                                 log_error("requested part of result string not found");
 172                                 break;
 173                         }
 174                         strscpy(tmp, sizeof(tmp), cpos);
 175                         /* %{2+}c copies the whole string from the second part on */
 176                         if (rest[0] != '+') {
 177                                 cpos = strchr(tmp, ' ');
 178                                 if (cpos)
 179                                         cpos[0] = '\0';
 180                         }
 181                         l = strpcpy(&s, l, tmp);
 182                 } else {
 183                         l = strpcpy(&s, l, event->program_result);
 184                 }
 185                 break;
 186         }
 187         case SUBST_ATTR: {
 188                 const char *value = NULL;
 189                 char vbuf[UTIL_NAME_SIZE];
 190                 size_t len;
 191                 int count;
 192
 193                 if (attr == NULL) {
 194                         log_error("missing file parameter for attr");
 195                         break;
 196                 }
 197
 198                 /* try to read the value specified by "[dmi/id]product_name" */
 199                 if (util_resolve_subsys_kernel(event->udev, attr, vbuf, sizeof(vbuf), 1) == 0)
 200                         value = vbuf;
 201
 202                 /* try to read the attribute the device */
 203                 if (value == NULL)
 204                         value = udev_device_get_sysattr_value(event->dev, attr);
 205
 206                 /* try to read the attribute of the parent device, other matches have selected */
 207                 if (value == NULL && event->dev_parent != NULL && event->dev_parent != event->dev)
 208                         value = udev_device_get_sysattr_value(event->dev_parent, attr);
 209
 210                 if (value == NULL)
 211                         break;
 212
 213                 /* strip trailing whitespace, and replace unwanted characters */
 214                 if (value != vbuf)
 215                         strscpy(vbuf, sizeof(vbuf), value);
 216                 len = strlen(vbuf);
 217                 while (len > 0 && isspace(vbuf[--len]))
 218                         vbuf[len] = '\0';
 219                 count = util_replace_chars(vbuf, UDEV_ALLOWED_CHARS_INPUT);
 220                 if (count > 0)
 221                         log_debug("%i character(s) replaced" , count);
 222                 l = strpcpy(&s, l, vbuf);
 223                 break;
 224         }
 225         case SUBST_PARENT: {
 226                 struct udev_device *dev_parent;
 227                 const char *devnode;
 228
 229                 dev_parent = udev_device_get_parent(event->dev);
 230                 if (dev_parent == NULL)
 231                         break;
 232                 devnode = udev_device_get_devnode(dev_parent);
 233                 if (devnode != NULL)
 234                         l = strpcpy(&s, l, devnode + strlen("/dev/"));
 235                 break;
 236         }
 237         case SUBST_DEVNODE:
 238                 if (udev_device_get_devnode(dev) != NULL)
 239                         l = strpcpy(&s, l, udev_device_get_devnode(dev));
 240                 break;
 241         case SUBST_NAME:
 242                 if (event->name != NULL)
 243                         l = strpcpy(&s, l, event->name);
 244                 else if (udev_device_get_devnode(dev) != NULL)
 245                         l = strpcpy(&s, l, udev_device_get_devnode(dev) + strlen("/dev/"));
 246                 else
 247                         l = strpcpy(&s, l, udev_device_get_sysname(dev));
 248                 break;
 249         case SUBST_LINKS: {
 250                 struct udev_list_entry *list_entry;
 251
 252                 list_entry = udev_device_get_devlinks_list_entry(dev);
 253                 if (list_entry == NULL)
 254                         break;
 255                 l = strpcpy(&s, l, udev_list_entry_get_name(list_entry) + strlen("/dev/"));
 256                 udev_list_entry_foreach(list_entry, udev_list_entry_get_next(list_entry))
 257                         l = strpcpyl(&s, l, " ", udev_list_entry_get_name(list_entry) + strlen("/dev/"), NULL);
 258                 break;
 259         }
 260         case SUBST_ROOT:
 261                 l = strpcpy(&s, l, "/dev");
 262                 break;
 263         case SUBST_SYS:
 264                 l = strpcpy(&s, l, "/sys");
 265                 break;
 266         case SUBST_ENV:
 267                 if (attr == NULL) {
 268                         break;
 269                 } else {
 270                         const char *value;
 271
 272                         value = udev_device_get_property_value(event->dev, attr);
 273                         if (value == NULL)
 274                                 break;
 275                         l = strpcpy(&s, l, value);
 276                         break;
 277                 }
 278         default:
 279                 log_error("unknown substitution type=%i", type);
 280                 break;
 281         }
 282
 283         return s - dest;
 284 }
 285
 286 size_t udev_event_apply_format(struct udev_event *event,
 287                                const char *src, char *dest, size_t size,
 288                                bool replace_whitespace) {
 289         struct udev_device *dev = event->dev;
 290         static const struct subst_map {
 291                 const char *name;
 292                 const char fmt;
 293                 enum subst_type type;
 294         } map[] = {
 295                 { .name = "devnode",  .fmt = 'N', .type = SUBST_DEVNODE },
 296                 { .name = "tempnode", .fmt = 'N', .type = SUBST_DEVNODE },
 297                 { .name = "attr",     .fmt = 's', .type = SUBST_ATTR },
 298                 { .name = "sysfs",    .fmt = 's', .type = SUBST_ATTR },
 299                 { .name = "env",      .fmt = 'E', .type = SUBST_ENV },
 300                 { .name = "kernel",   .fmt = 'k', .type = SUBST_KERNEL },
 301                 { .name = "number",   .fmt = 'n', .type = SUBST_KERNEL_NUMBER },
 302                 { .name = "driver",   .fmt = 'd', .type = SUBST_DRIVER },
 303                 { .name = "devpath",  .fmt = 'p', .type = SUBST_DEVPATH },
 304                 { .name = "id",       .fmt = 'b', .type = SUBST_ID },
 305                 { .name = "major",    .fmt = 'M', .type = SUBST_MAJOR },
 306                 { .name = "minor",    .fmt = 'm', .type = SUBST_MINOR },
 307                 { .name = "result",   .fmt = 'c', .type = SUBST_RESULT },
 308                 { .name = "parent",   .fmt = 'P', .type = SUBST_PARENT },
 309                 { .name = "name",     .fmt = 'D', .type = SUBST_NAME },
 310                 { .name = "links",    .fmt = 'L', .type = SUBST_LINKS },
 311                 { .name = "root",     .fmt = 'r', .type = SUBST_ROOT },
 312                 { .name = "sys",      .fmt = 'S', .type = SUBST_SYS },
 313         };
 314         const char *from;
 315         char *s;
 316         size_t l;
 317
 318         assert(dev);
 319
 320         from = src;
 321         s = dest;
 322         l = size;
 323
 324         for (;;) {
 325                 enum subst_type type = SUBST_UNKNOWN;
 326                 char attrbuf[UTIL_PATH_SIZE];
 327                 char *attr = NULL;
 328                 size_t subst_len;
 329
 330                 while (from[0] != '\0') {
 331                         if (from[0] == '$') {
 332                                 /* substitute named variable */
 333                                 unsigned int i;
 334
 335                                 if (from[1] == '$') {
 336                                         from++;
 337                                         goto copy;
 338                                 }
 339
 340                                 for (i = 0; i < ELEMENTSOF(map); i++) {
 341                                         if (startswith(&from[1], map[i].name)) {
 342                                                 type = map[i].type;
 343                                                 from += strlen(map[i].name)+1;
 344                                                 goto subst;
 345                                         }
 346                                 }
 347                         } else if (from[0] == '%') {
 348                                 /* substitute format char */
 349                                 unsigned int i;
 350
 351                                 if (from[1] == '%') {
 352                                         from++;
 353                                         goto copy;
 354                                 }
 355
 356                                 for (i = 0; i < ELEMENTSOF(map); i++) {
 357                                         if (from[1] == map[i].fmt) {
 358                                                 type = map[i].type;
 359                                                 from += 2;
 360                                                 goto subst;
 361                                         }
 362                                 }
 363                         }
 364 copy:
 365                         /* copy char */
 366                         if (l < 2) /* need space for this char and the terminating NUL */
 367                                 goto out;
 368                         s[0] = from[0];
 369                         from++;
 370                         s++;
 371                         l--;
 372                 }
 373
 374                 goto out;
 375 subst:
 376                 /* extract possible $format{attr} */
 377                 if (from[0] == '{') {
 378                         unsigned int i;
 379
 380                         from++;
 381                         for (i = 0; from[i] != '}'; i++)
 382                                 if (from[i] == '\0') {
 383                                         log_error("missing closing brace for format '%s'", src);
 384                                         goto out;
 385                                 }
 386
 387                         if (i >= sizeof(attrbuf))
 388                                 goto out;
 389                         memcpy(attrbuf, from, i);
 390                         attrbuf[i] = '\0';
 391                         from += i+1;
 392                         attr = attrbuf;
 393                 } else {
 394                         attr = NULL;
 395                 }
 396
 397                 subst_len = subst_format_var(event, dev, type, attr, s, l);
 398
 399                 /* SUBST_RESULT handles spaces itself */
 400                 if (replace_whitespace && type != SUBST_RESULT)
 401                         /* util_replace_whitespace can replace in-place,
 402                          * and does nothing if subst_len == 0
 403                          */
 404                         subst_len = util_replace_whitespace(s, s, subst_len);
 405
 406                 s += subst_len;
 407                 l -= subst_len;
 408         }
 409
 410 out:
 411         assert(l >= 1);
 412         s[0] = '\0';
 413         return l;
 414 }
 415
 416 static int spawn_exec(struct udev_event *event,
 417                       const char *cmd, char *const argv[], char **envp,
 418                       int fd_stdout, int fd_stderr) {
 419         _cleanup_close_ int fd = -1;
 420         int r;
 421
 422         /* discard child output or connect to pipe */
 423         fd = open("/dev/null", O_RDWR);
 424         if (fd >= 0) {
 425                 r = dup2(fd, STDIN_FILENO);
 426                 if (r < 0)
 427                         log_warning_errno(errno, "redirecting stdin failed: %m");
 428
 429                 if (fd_stdout < 0) {
 430                         r = dup2(fd, STDOUT_FILENO);
 431                         if (r < 0)
 432                                 log_warning_errno(errno, "redirecting stdout failed: %m");
 433                 }
 434
 435                 if (fd_stderr < 0) {
 436                         r = dup2(fd, STDERR_FILENO);
 437                         if (r < 0)
 438                                 log_warning_errno(errno, "redirecting stderr failed: %m");
 439                 }
 440         } else
 441                 log_warning_errno(errno, "open /dev/null failed: %m");
 442
 443         /* connect pipes to std{out,err} */
 444         if (fd_stdout >= 0) {
 445                 r = dup2(fd_stdout, STDOUT_FILENO);
 446                 if (r < 0)
 447                         log_warning_errno(errno, "redirecting stdout failed: %m");
 448
 449                 fd_stdout = safe_close(fd_stdout);
 450         }
 451
 452         if (fd_stderr >= 0) {
 453                 r = dup2(fd_stderr, STDERR_FILENO);
 454                 if (r < 0)
 455                         log_warning_errno(errno, "redirecting stdout failed: %m");
 456
 457                 fd_stderr = safe_close(fd_stderr);
 458         }
 459
 460         /* terminate child in case parent goes away */
 461         prctl(PR_SET_PDEATHSIG, SIGTERM);
 462
 463         /* restore sigmask before exec */
 464         (void) reset_signal_mask();
 465
 466         execve(argv[0], argv, envp);
 467
 468         /* exec failed */
 469         return log_error_errno(errno, "failed to execute '%s' '%s': %m", argv[0], cmd);
 470 }
 471
 472 static void spawn_read(struct udev_event *event,
 473                        usec_t timeout_usec,
 474                        const char *cmd,
 475                        int fd_stdout, int fd_stderr,
 476                        char *result, size_t ressize) {
 477         _cleanup_close_ int fd_ep = -1;
 478         struct epoll_event ep_outpipe = {
 479                 .events = EPOLLIN,
 480                 .data.ptr = &fd_stdout,
 481         };
 482         struct epoll_event ep_errpipe = {
 483                 .events = EPOLLIN,
 484                 .data.ptr = &fd_stderr,
 485         };
 486         size_t respos = 0;
 487         int r;
 488
 489         /* read from child if requested */
 490         if (fd_stdout < 0 && fd_stderr < 0)
 491                 return;
 492
 493         fd_ep = epoll_create1(EPOLL_CLOEXEC);
 494         if (fd_ep < 0) {
 495                 log_error_errno(errno, "error creating epoll fd: %m");
 496                 return;
 497         }
 498
 499         if (fd_stdout >= 0) {
 500                 r = epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_stdout, &ep_outpipe);
 501                 if (r < 0) {
 502                         log_error_errno(errno, "fail to add stdout fd to epoll: %m");
 503                         return;
 504                 }
 505         }
 506
 507         if (fd_stderr >= 0) {
 508                 r = epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_stderr, &ep_errpipe);
 509                 if (r < 0) {
 510                         log_error_errno(errno, "fail to add stderr fd to epoll: %m");
 511                         return;
 512                 }
 513         }
 514
 515         /* read child output */
 516         while (fd_stdout >= 0 || fd_stderr >= 0) {
 517                 int timeout;
 518                 int fdcount;
 519                 struct epoll_event ev[4];
 520                 int i;
 521
 522                 if (timeout_usec > 0) {
 523                         usec_t age_usec;
 524
 525                         age_usec = now(CLOCK_MONOTONIC) - event->birth_usec;
 526                         if (age_usec >= timeout_usec) {
 527                                 log_error("timeout '%s'", cmd);
 528                                 return;
 529                         }
 530                         timeout = ((timeout_usec - age_usec) / USEC_PER_MSEC) + MSEC_PER_SEC;
 531                 } else {
 532                         timeout = -1;
 533                 }
 534
 535                 fdcount = epoll_wait(fd_ep, ev, ELEMENTSOF(ev), timeout);
 536                 if (fdcount < 0) {
 537                         if (errno == EINTR)
 538                                 continue;
 539                         log_error_errno(errno, "failed to poll: %m");
 540                         return;
 541                 } else if (fdcount == 0) {
 542                         log_error("timeout '%s'", cmd);
 543                         return;
 544                 }
 545
 546                 for (i = 0; i < fdcount; i++) {
 547                         int *fd = (int *)ev[i].data.ptr;
 548
 549                         if (*fd < 0)
 550                                 continue;
 551
 552                         if (ev[i].events & EPOLLIN) {
 553                                 ssize_t count;
 554                                 char buf[4096];
 555
 556                                 count = read(*fd, buf, sizeof(buf)-1);
 557                                 if (count <= 0)
 558                                         continue;
 559                                 buf[count] = '\0';
 560
 561                                 /* store stdout result */
 562                                 if (result != NULL && *fd == fd_stdout) {
 563                                         if (respos + count < ressize) {
 564                                                 memcpy(&result[respos], buf, count);
 565                                                 respos += count;
 566                                         } else {
 567                                                 log_error("'%s' ressize %zu too short", cmd, ressize);
 568                                         }
 569                                 }
 570
 571                                 /* log debug output only if we watch stderr */
 572                                 if (fd_stderr >= 0) {
 573                                         char *pos;
 574                                         char *line;
 575
 576                                         pos = buf;
 577                                         while ((line = strsep(&pos, "\n"))) {
 578                                                 if (pos != NULL || line[0] != '\0')
 579                                                         log_debug("'%s'(%s) '%s'", cmd, *fd == fd_stdout ? "out" : "err" , line);
 580                                         }
 581                                 }
 582                         } else if (ev[i].events & EPOLLHUP) {
 583                                 r = epoll_ctl(fd_ep, EPOLL_CTL_DEL, *fd, NULL);
 584                                 if (r < 0) {
 585                                         log_error_errno(errno, "failed to remove fd from epoll: %m");
 586                                         return;
 587                                 }
 588                                 *fd = -1;
 589                         }
 590                 }
 591         }
 592
 593         /* return the child's stdout string */
 594         if (result != NULL)
 595                 result[respos] = '\0';
 596 }
 597
 598 static int on_spawn_timeout(sd_event_source *s, uint64_t usec, void *userdata) {
 599         Spawn *spawn = userdata;
 600         char timeout[FORMAT_TIMESTAMP_RELATIVE_MAX];
 601
 602         assert(spawn);
 603
 604         kill_and_sigcont(spawn->pid, SIGKILL);
 605
 606         log_error("spawned process '%s' ["PID_FMT"] timed out after %s, killing", spawn->cmd, spawn->pid,
 607                   format_timestamp_relative(timeout, sizeof(timeout), spawn->timeout));
 608
 609         return 1;
 610 }
 611
 612 static int on_spawn_timeout_warning(sd_event_source *s, uint64_t usec, void *userdata) {
 613         Spawn *spawn = userdata;
 614         char timeout[FORMAT_TIMESTAMP_RELATIVE_MAX];
 615
 616         assert(spawn);
 617
 618         log_warning("spawned process '%s' ["PID_FMT"] is taking longer than %s to complete", spawn->cmd, spawn->pid,
 619                     format_timestamp_relative(timeout, sizeof(timeout), spawn->timeout));
 620
 621         return 1;
 622 }
 623
 624 static int on_spawn_sigchld(sd_event_source *s, const siginfo_t *si, void *userdata) {
 625         Spawn *spawn = userdata;
 626
 627         assert(spawn);
 628
 629         switch (si->si_code) {
 630         case CLD_EXITED:
 631                 if (si->si_status == 0) {
 632                         log_debug("Process '%s' succeeded.", spawn->cmd);
 633                         sd_event_exit(sd_event_source_get_event(s), 0);
 634
 635                         return 1;
 636                 } else if (spawn->accept_failure)
 637                         log_debug("Process '%s' failed with exit code %i.", spawn->cmd, si->si_status);
 638                 else
 639                         log_warning("Process '%s' failed with exit code %i.", spawn->cmd, si->si_status);
 640
 641                 break;
 642         case CLD_KILLED:
 643         case CLD_DUMPED:
 644                 log_warning("Process '%s' terminated by signal %s.", spawn->cmd, signal_to_string(si->si_status));
 645
 646                 break;
 647         default:
 648                 log_error("Process '%s' failed due to unknown reason.", spawn->cmd);
 649         }
 650
 651         sd_event_exit(sd_event_source_get_event(s), -EIO);
 652
 653         return 1;
 654 }
 655
 656 static int spawn_wait(struct udev_event *event,
 657                       usec_t timeout_usec,
 658                       usec_t timeout_warn_usec,
 659                       const char *cmd, pid_t pid,
 660                       bool accept_failure) {
 661         Spawn spawn = {
 662                 .cmd = cmd,
 663                 .pid = pid,
 664                 .accept_failure = accept_failure,
 665         };
 666         _cleanup_(sd_event_unrefp) sd_event *e = NULL;
 667         int r, ret;
 668
 669         r = sd_event_new(&e);
 670         if (r < 0)
 671                 return r;
 672
 673         if (timeout_usec > 0) {
 674                 usec_t usec, age_usec;
 675
 676                 usec = now(CLOCK_MONOTONIC);
 677                 age_usec = usec - event->birth_usec;
 678                 if (age_usec < timeout_usec) {
 679                         if (timeout_warn_usec > 0 && timeout_warn_usec < timeout_usec && age_usec < timeout_warn_usec) {
 680                                 spawn.timeout_warn = timeout_warn_usec - age_usec;
 681
 682                                 r = sd_event_add_time(e, NULL, CLOCK_MONOTONIC,
 683                                                       usec + spawn.timeout_warn, USEC_PER_SEC,
 684                                                       on_spawn_timeout_warning, &spawn);
 685                                 if (r < 0)
 686                                         return r;
 687                         }
 688
 689                         spawn.timeout = timeout_usec - age_usec;
 690
 691                         r = sd_event_add_time(e, NULL, CLOCK_MONOTONIC,
 692                                               usec + spawn.timeout, USEC_PER_SEC, on_spawn_timeout, &spawn);
 693                         if (r < 0)
 694                                 return r;
 695                 }
 696         }
 697
 698         r = sd_event_add_child(e, NULL, pid, WEXITED, on_spawn_sigchld, &spawn);
 699         if (r < 0)
 700                 return r;
 701
 702         r = sd_event_loop(e);
 703         if (r < 0)
 704                 return r;
 705
 706         r = sd_event_get_exit_code(e, &ret);
 707         if (r < 0)
 708                 return r;
 709
 710         return ret;
 711 }
 712
 713 int udev_build_argv(struct udev *udev, char *cmd, int *argc, char *argv[]) {
 714         int i = 0;
 715         char *pos;
 716
 717         if (strchr(cmd, ' ') == NULL) {
 718                 argv[i++] = cmd;
 719                 goto out;
 720         }
 721
 722         pos = cmd;
 723         while (pos != NULL && pos[0] != '\0') {
 724                 if (IN_SET(pos[0], '\'', '"')) {
 725                         /* do not separate quotes or double quotes */
 726                         char delim[2] = { pos[0], '\0' };
 727
 728                         pos++;
 729                         argv[i] = strsep(&pos, delim);
 730                         if (pos != NULL)
 731                                 while (pos[0] == ' ')
 732                                         pos++;
 733                 } else {
 734                         argv[i] = strsep(&pos, " ");
 735                         if (pos != NULL)
 736                                 while (pos[0] == ' ')
 737                                         pos++;
 738                 }
 739                 i++;
 740         }
 741 out:
 742         argv[i] = NULL;
 743         if (argc)
 744                 *argc = i;
 745         return 0;
 746 }
 747
 748 int udev_event_spawn(struct udev_event *event,
 749                      usec_t timeout_usec,
 750                      usec_t timeout_warn_usec,
 751                      bool accept_failure,
 752                      const char *cmd,
 753                      char *result, size_t ressize) {
 754         int outpipe[2] = {-1, -1};
 755         int errpipe[2] = {-1, -1};
 756         pid_t pid;
 757         int err = 0;
 758
 759         /* pipes from child to parent */
 760         if (result != NULL || log_get_max_level() >= LOG_INFO) {
 761                 if (pipe2(outpipe, O_NONBLOCK) != 0) {
 762                         err = log_error_errno(errno, "pipe failed: %m");
 763                         goto out;
 764                 }
 765         }
 766         if (log_get_max_level() >= LOG_INFO) {
 767                 if (pipe2(errpipe, O_NONBLOCK) != 0) {
 768                         err = log_error_errno(errno, "pipe failed: %m");
 769                         goto out;
 770                 }
 771         }
 772
 773         pid = fork();
 774         switch(pid) {
 775         case 0:
 776         {
 777                 char arg[UTIL_PATH_SIZE];
 778                 char *argv[128];
 779                 char program[UTIL_PATH_SIZE];
 780
 781                 /* child closes parent's ends of pipes */
 782                 outpipe[READ_END] = safe_close(outpipe[READ_END]);
 783                 errpipe[READ_END] = safe_close(errpipe[READ_END]);
 784
 785                 strscpy(arg, sizeof(arg), cmd);
 786                 udev_build_argv(event->udev, arg, NULL, argv);
 787
 788                 /* allow programs in /usr/lib/udev/ to be called without the path */
 789                 if (argv[0][0] != '/') {
 790                         strscpyl(program, sizeof(program), UDEVLIBEXECDIR "/", argv[0], NULL);
 791                         argv[0] = program;
 792                 }
 793
 794                 log_debug("starting '%s'", cmd);
 795
 796                 spawn_exec(event, cmd, argv, udev_device_get_properties_envp(event->dev),
 797                            outpipe[WRITE_END], errpipe[WRITE_END]);
 798
 799                 _exit(2);
 800         }
 801         case -1:
 802                 log_error_errno(errno, "fork of '%s' failed: %m", cmd);
 803                 err = -1;
 804                 goto out;
 805         default:
 806                 /* parent closed child's ends of pipes */
 807                 outpipe[WRITE_END] = safe_close(outpipe[WRITE_END]);
 808                 errpipe[WRITE_END] = safe_close(errpipe[WRITE_END]);
 809
 810                 spawn_read(event,
 811                            timeout_usec,
 812                            cmd,
 813                            outpipe[READ_END], errpipe[READ_END],
 814                            result, ressize);
 815
 816                 err = spawn_wait(event, timeout_usec, timeout_warn_usec, cmd, pid, accept_failure);
 817         }
 818
 819 out:
 820         if (outpipe[READ_END] >= 0)
 821                 close(outpipe[READ_END]);
 822         if (outpipe[WRITE_END] >= 0)
 823                 close(outpipe[WRITE_END]);
 824         if (errpipe[READ_END] >= 0)
 825                 close(errpipe[READ_END]);
 826         if (errpipe[WRITE_END] >= 0)
 827                 close(errpipe[WRITE_END]);
 828         return err;
 829 }
 830
 831 static int rename_netif(struct udev_event *event) {
 832         struct udev_device *dev = event->dev;
 833         char name[IFNAMSIZ];
 834         const char *oldname;
 835         int r;
 836
 837         oldname = udev_device_get_sysname(dev);
 838
 839         strscpy(name, IFNAMSIZ, event->name);
 840
 841         r = rtnl_set_link_name(&event->rtnl, udev_device_get_ifindex(dev), name);
 842         if (r < 0)
 843                 return log_error_errno(r, "Error changing net interface name '%s' to '%s': %m", oldname, name);
 844
 845         log_debug("renamed network interface '%s' to '%s'", oldname, name);
 846
 847         return 0;
 848 }
 849
 850 void udev_event_execute_rules(struct udev_event *event,
 851                               usec_t timeout_usec, usec_t timeout_warn_usec,
 852                               struct udev_list *properties_list,
 853                               struct udev_rules *rules) {
 854         struct udev_device *dev = event->dev;
 855
 856         if (udev_device_get_subsystem(dev) == NULL)
 857                 return;
 858
 859         if (streq(udev_device_get_action(dev), "remove")) {
 860                 udev_device_read_db(dev);
 861                 udev_device_tag_index(dev, NULL, false);
 862                 udev_device_delete_db(dev);
 863
 864                 if (major(udev_device_get_devnum(dev)) != 0)
 865                         udev_watch_end(event->udev, dev);
 866
 867                 udev_rules_apply_to_event(rules, event,
 868                                           timeout_usec, timeout_warn_usec,
 869                                           properties_list);
 870
 871                 if (major(udev_device_get_devnum(dev)) != 0)
 872                         udev_node_remove(dev);
 873         } else {
 874                 event->dev_db = udev_device_clone_with_db(dev);
 875                 if (event->dev_db != NULL) {
 876                         /* disable watch during event processing */
 877                         if (major(udev_device_get_devnum(dev)) != 0)
 878                                 udev_watch_end(event->udev, event->dev_db);
 879
 880                         if (major(udev_device_get_devnum(dev)) == 0 &&
 881                             streq(udev_device_get_action(dev), "move"))
 882                                 udev_device_copy_properties(dev, event->dev_db);
 883                 }
 884
 885                 udev_rules_apply_to_event(rules, event,
 886                                           timeout_usec, timeout_warn_usec,
 887                                           properties_list);
 888
 889                 /* rename a new network interface, if needed */
 890                 if (udev_device_get_ifindex(dev) > 0 && streq(udev_device_get_action(dev), "add") &&
 891                     event->name != NULL && !streq(event->name, udev_device_get_sysname(dev))) {
 892                         int r;
 893
 894                         r = rename_netif(event);
 895                         if (r < 0)
 896                                 log_warning_errno(r, "could not rename interface '%d' from '%s' to '%s': %m", udev_device_get_ifindex(dev),
 897                                                   udev_device_get_sysname(dev), event->name);
 898                         else {
 899                                 r = udev_device_rename(dev, event->name);
 900                                 if (r < 0)
 901                                         log_warning_errno(r, "renamed interface '%d' from '%s' to '%s', but could not update udev_device: %m",
 902                                                           udev_device_get_ifindex(dev), udev_device_get_sysname(dev), event->name);
 903                                 else
 904                                         log_debug("changed devpath to '%s'", udev_device_get_devpath(dev));
 905                         }
 906                 }
 907
 908                 if (major(udev_device_get_devnum(dev)) > 0) {
 909                         bool apply;
 910
 911                         /* remove/update possible left-over symlinks from old database entry */
 912                         if (event->dev_db != NULL)
 913                                 udev_node_update_old_links(dev, event->dev_db);
 914
 915                         if (!event->owner_set)
 916                                 event->uid = udev_device_get_devnode_uid(dev);
 917
 918                         if (!event->group_set)
 919                                 event->gid = udev_device_get_devnode_gid(dev);
 920
 921                         if (!event->mode_set) {
 922                                 if (udev_device_get_devnode_mode(dev) > 0) {
 923                                         /* kernel supplied value */
 924                                         event->mode = udev_device_get_devnode_mode(dev);
 925                                 } else if (event->gid > 0) {
 926                                         /* default 0660 if a group is assigned */
 927                                         event->mode = 0660;
 928                                 } else {
 929                                         /* default 0600 */
 930                                         event->mode = 0600;
 931                                 }
 932                         }
 933
 934                         apply = streq(udev_device_get_action(dev), "add") || event->owner_set || event->group_set || event->mode_set;
 935                         udev_node_add(dev, apply, event->mode, event->uid, event->gid, &event->seclabel_list);
 936                 }
 937
 938                 /* preserve old, or get new initialization timestamp */
 939                 udev_device_ensure_usec_initialized(event->dev, event->dev_db);
 940
 941                 /* (re)write database file */
 942                 udev_device_tag_index(dev, event->dev_db, true);
 943                 udev_device_update_db(dev);
 944                 udev_device_set_is_initialized(dev);
 945
 946                 event->dev_db = udev_device_unref(event->dev_db);
 947         }
 948 }
 949
 950 void udev_event_execute_run(struct udev_event *event, usec_t timeout_usec, usec_t timeout_warn_usec) {
 951         struct udev_list_entry *list_entry;
 952
 953         udev_list_entry_foreach(list_entry, udev_list_get_entry(&event->run_list)) {
 954                 char command[UTIL_PATH_SIZE];
 955                 const char *cmd = udev_list_entry_get_name(list_entry);
 956                 enum udev_builtin_cmd builtin_cmd = udev_list_entry_get_num(list_entry);
 957
 958                 udev_event_apply_format(event, cmd, command, sizeof(command), false);
 959
 960                 if (builtin_cmd < UDEV_BUILTIN_MAX)
 961                         udev_builtin_run(event->dev, builtin_cmd, command, false);
 962                 else {
 963                         if (event->exec_delay > 0) {
 964                                 log_debug("delay execution of '%s'", command);
 965                                 sleep(event->exec_delay);
 966                         }
 967
 968                         udev_event_spawn(event, timeout_usec, timeout_warn_usec, false, command, NULL, 0);
 969                 }
 970         }
 971 }