src/udev/udev-event.c

   1 /* SPDX-License-Identifier: GPL-2.0+ */
   2
   3 #include <ctype.h>
   4 #include <errno.h>
   5 #include <fcntl.h>
   6 #include <net/if.h>
   7 #include <stddef.h>
   8 #include <stdio.h>
   9 #include <stdlib.h>
  10 #include <sys/wait.h>
  11 #include <unistd.h>
  12
  13 #include "sd-event.h"
  14
  15 #include "alloc-util.h"
  16 #include "device-private.h"
  17 #include "device-util.h"
  18 #include "fd-util.h"
  19 #include "fs-util.h"
  20 #include "format-util.h"
  21 #include "libudev-util.h"
  22 #include "netlink-util.h"
  23 #include "path-util.h"
  24 #include "process-util.h"
  25 #include "rlimit-util.h"
  26 #include "signal-util.h"
  27 #include "stdio-util.h"
  28 #include "string-util.h"
  29 #include "strv.h"
  30 #include "strxcpyx.h"
  31 #include "udev-builtin.h"
  32 #include "udev-event.h"
  33 #include "udev-node.h"
  34 #include "udev-util.h"
  35 #include "udev-watch.h"
  36 #include "user-util.h"
  37
  38 typedef struct Spawn {
  39         const char *cmd;
  40         pid_t pid;
  41         usec_t timeout_warn_usec;
  42         usec_t timeout_usec;
  43         usec_t event_birth_usec;
  44         bool accept_failure;
  45         int fd_stdout;
  46         int fd_stderr;
  47         char *result;
  48         size_t result_size;
  49         size_t result_len;
  50 } Spawn;
  51
  52 UdevEvent *udev_event_new(sd_device *dev, usec_t exec_delay_usec, sd_netlink *rtnl) {
  53         UdevEvent *event;
  54
  55         assert(dev);
  56
  57         event = new(UdevEvent, 1);
  58         if (!event)
  59                 return NULL;
  60
  61         *event = (UdevEvent) {
  62                 .dev = sd_device_ref(dev),
  63                 .birth_usec = now(CLOCK_MONOTONIC),
  64                 .exec_delay_usec = exec_delay_usec,
  65                 .rtnl = sd_netlink_ref(rtnl),
  66                 .uid = UID_INVALID,
  67                 .gid = GID_INVALID,
  68                 .mode = MODE_INVALID,
  69         };
  70
  71         return event;
  72 }
  73
  74 UdevEvent *udev_event_free(UdevEvent *event) {
  75         if (!event)
  76                 return NULL;
  77
  78         sd_device_unref(event->dev);
  79         sd_device_unref(event->dev_db_clone);
  80         sd_netlink_unref(event->rtnl);
  81         ordered_hashmap_free_free_key(event->run_list);
  82         ordered_hashmap_free_free_free(event->seclabel_list);
  83         free(event->program_result);
  84         free(event->name);
  85
  86         return mfree(event);
  87 }
  88
  89 typedef enum {
  90         FORMAT_SUBST_DEVNODE,
  91         FORMAT_SUBST_ATTR,
  92         FORMAT_SUBST_ENV,
  93         FORMAT_SUBST_KERNEL,
  94         FORMAT_SUBST_KERNEL_NUMBER,
  95         FORMAT_SUBST_DRIVER,
  96         FORMAT_SUBST_DEVPATH,
  97         FORMAT_SUBST_ID,
  98         FORMAT_SUBST_MAJOR,
  99         FORMAT_SUBST_MINOR,
 100         FORMAT_SUBST_RESULT,
 101         FORMAT_SUBST_PARENT,
 102         FORMAT_SUBST_NAME,
 103         FORMAT_SUBST_LINKS,
 104         FORMAT_SUBST_ROOT,
 105         FORMAT_SUBST_SYS,
 106         _FORMAT_SUBST_TYPE_MAX,
 107         _FORMAT_SUBST_TYPE_INVALID = -1
 108 } FormatSubstitutionType;
 109
 110 struct subst_map_entry {
 111         const char *name;
 112         const char fmt;
 113         FormatSubstitutionType type;
 114 };
 115
 116 static const struct subst_map_entry map[] = {
 117            { .name = "devnode",  .fmt = 'N', .type = FORMAT_SUBST_DEVNODE },
 118            { .name = "tempnode", .fmt = 'N', .type = FORMAT_SUBST_DEVNODE }, /* deprecated */
 119            { .name = "attr",     .fmt = 's', .type = FORMAT_SUBST_ATTR },
 120            { .name = "sysfs",    .fmt = 's', .type = FORMAT_SUBST_ATTR }, /* deprecated */
 121            { .name = "env",      .fmt = 'E', .type = FORMAT_SUBST_ENV },
 122            { .name = "kernel",   .fmt = 'k', .type = FORMAT_SUBST_KERNEL },
 123            { .name = "number",   .fmt = 'n', .type = FORMAT_SUBST_KERNEL_NUMBER },
 124            { .name = "driver",   .fmt = 'd', .type = FORMAT_SUBST_DRIVER },
 125            { .name = "devpath",  .fmt = 'p', .type = FORMAT_SUBST_DEVPATH },
 126            { .name = "id",       .fmt = 'b', .type = FORMAT_SUBST_ID },
 127            { .name = "major",    .fmt = 'M', .type = FORMAT_SUBST_MAJOR },
 128            { .name = "minor",    .fmt = 'm', .type = FORMAT_SUBST_MINOR },
 129            { .name = "result",   .fmt = 'c', .type = FORMAT_SUBST_RESULT },
 130            { .name = "parent",   .fmt = 'P', .type = FORMAT_SUBST_PARENT },
 131            { .name = "name",     .fmt = 'D', .type = FORMAT_SUBST_NAME },
 132            { .name = "links",    .fmt = 'L', .type = FORMAT_SUBST_LINKS },
 133            { .name = "root",     .fmt = 'r', .type = FORMAT_SUBST_ROOT },
 134            { .name = "sys",      .fmt = 'S', .type = FORMAT_SUBST_SYS },
 135 };
 136
 137 static ssize_t udev_event_subst_format(
 138                 UdevEvent *event,
 139                 FormatSubstitutionType type,
 140                 const char *attr,
 141                 char *dest,
 142                 size_t l) {
 143         sd_device *parent, *dev = event->dev;
 144         const char *val = NULL;
 145         char *s = dest;
 146         dev_t devnum;
 147         int r;
 148
 149         switch (type) {
 150         case FORMAT_SUBST_DEVPATH:
 151                 r = sd_device_get_devpath(dev, &val);
 152                 if (r < 0)
 153                         return r;
 154                 l = strpcpy(&s, l, val);
 155                 break;
 156         case FORMAT_SUBST_KERNEL:
 157                 r = sd_device_get_sysname(dev, &val);
 158                 if (r < 0)
 159                         return r;
 160                 l = strpcpy(&s, l, val);
 161                 break;
 162         case FORMAT_SUBST_KERNEL_NUMBER:
 163                 r = sd_device_get_sysnum(dev, &val);
 164                 if (r == -ENOENT)
 165                         goto null_terminate;
 166                 if (r < 0)
 167                         return r;
 168                 l = strpcpy(&s, l, val);
 169                 break;
 170         case FORMAT_SUBST_ID:
 171                 if (!event->dev_parent)
 172                         goto null_terminate;
 173                 r = sd_device_get_sysname(event->dev_parent, &val);
 174                 if (r < 0)
 175                         return r;
 176                 l = strpcpy(&s, l, val);
 177                 break;
 178         case FORMAT_SUBST_DRIVER:
 179                 if (!event->dev_parent)
 180                         goto null_terminate;
 181                 r = sd_device_get_driver(event->dev_parent, &val);
 182                 if (r == -ENOENT)
 183                         goto null_terminate;
 184                 if (r < 0)
 185                         return r;
 186                 l = strpcpy(&s, l, val);
 187                 break;
 188         case FORMAT_SUBST_MAJOR:
 189         case FORMAT_SUBST_MINOR: {
 190                 char buf[DECIMAL_STR_MAX(unsigned)];
 191
 192                 r = sd_device_get_devnum(dev, &devnum);
 193                 if (r < 0 && r != -ENOENT)
 194                         return r;
 195                 xsprintf(buf, "%u", r < 0 ? 0 : type == FORMAT_SUBST_MAJOR ? major(devnum) : minor(devnum));
 196                 l = strpcpy(&s, l, buf);
 197                 break;
 198         }
 199         case FORMAT_SUBST_RESULT: {
 200                 char *rest;
 201                 int i;
 202
 203                 if (!event->program_result)
 204                         goto null_terminate;
 205
 206                 /* get part of the result string */
 207                 i = 0;
 208                 if (attr)
 209                         i = strtoul(attr, &rest, 10);
 210                 if (i > 0) {
 211                         char result[UTIL_PATH_SIZE], tmp[UTIL_PATH_SIZE], *cpos;
 212
 213                         strscpy(result, sizeof(result), event->program_result);
 214                         cpos = result;
 215                         while (--i) {
 216                                 while (cpos[0] != '\0' && !isspace(cpos[0]))
 217                                         cpos++;
 218                                 while (isspace(cpos[0]))
 219                                         cpos++;
 220                                 if (cpos[0] == '\0')
 221                                         break;
 222                         }
 223                         if (i > 0) {
 224                                 log_error("requested part of result string not found");
 225                                 break;
 226                         }
 227                         strscpy(tmp, sizeof(tmp), cpos);
 228                         /* %{2+}c copies the whole string from the second part on */
 229                         if (rest[0] != '+') {
 230                                 cpos = strchr(tmp, ' ');
 231                                 if (cpos)
 232                                         cpos[0] = '\0';
 233                         }
 234                         l = strpcpy(&s, l, tmp);
 235                 } else
 236                         l = strpcpy(&s, l, event->program_result);
 237                 break;
 238         }
 239         case FORMAT_SUBST_ATTR: {
 240                 char vbuf[UTIL_NAME_SIZE];
 241                 size_t len;
 242                 int count;
 243
 244                 if (!attr)
 245                         return -EINVAL;
 246
 247                 /* try to read the value specified by "[dmi/id]product_name" */
 248                 if (util_resolve_subsys_kernel(attr, vbuf, sizeof(vbuf), true) == 0)
 249                         val = vbuf;
 250
 251                 /* try to read the attribute the device */
 252                 if (!val)
 253                         (void) sd_device_get_sysattr_value(dev, attr, &val);
 254
 255                 /* try to read the attribute of the parent device, other matches have selected */
 256                 if (!val && event->dev_parent && event->dev_parent != dev)
 257                         (void) sd_device_get_sysattr_value(event->dev_parent, attr, &val);
 258
 259                 if (!val)
 260                         goto null_terminate;
 261
 262                 /* strip trailing whitespace, and replace unwanted characters */
 263                 if (val != vbuf)
 264                         strscpy(vbuf, sizeof(vbuf), val);
 265                 len = strlen(vbuf);
 266                 while (len > 0 && isspace(vbuf[--len]))
 267                         vbuf[len] = '\0';
 268                 count = util_replace_chars(vbuf, UDEV_ALLOWED_CHARS_INPUT);
 269                 if (count > 0)
 270                         log_device_debug(dev, "%i character(s) replaced", count);
 271                 l = strpcpy(&s, l, vbuf);
 272                 break;
 273         }
 274         case FORMAT_SUBST_PARENT:
 275                 r = sd_device_get_parent(dev, &parent);
 276                 if (r == -ENODEV)
 277                         goto null_terminate;
 278                 if (r < 0)
 279                         return r;
 280                 r = sd_device_get_devname(parent, &val);
 281                 if (r == -ENOENT)
 282                         goto null_terminate;
 283                 if (r < 0)
 284                         return r;
 285                 l = strpcpy(&s, l, val + STRLEN("/dev/"));
 286                 break;
 287         case FORMAT_SUBST_DEVNODE:
 288                 r = sd_device_get_devname(dev, &val);
 289                 if (r == -ENOENT)
 290                         goto null_terminate;
 291                 if (r < 0)
 292                         return r;
 293                 l = strpcpy(&s, l, val);
 294                 break;
 295         case FORMAT_SUBST_NAME:
 296                 if (event->name)
 297                         l = strpcpy(&s, l, event->name);
 298                 else if (sd_device_get_devname(dev, &val) >= 0)
 299                         l = strpcpy(&s, l, val + STRLEN("/dev/"));
 300                 else {
 301                         r = sd_device_get_sysname(dev, &val);
 302                         if (r < 0)
 303                                 return r;
 304                         l = strpcpy(&s, l, val);
 305                 }
 306                 break;
 307         case FORMAT_SUBST_LINKS:
 308                 FOREACH_DEVICE_DEVLINK(dev, val)
 309                         if (s == dest)
 310                                 l = strpcpy(&s, l, val + STRLEN("/dev/"));
 311                         else
 312                                 l = strpcpyl(&s, l, " ", val + STRLEN("/dev/"), NULL);
 313                 if (s == dest)
 314                         goto null_terminate;
 315                 break;
 316         case FORMAT_SUBST_ROOT:
 317                 l = strpcpy(&s, l, "/dev");
 318                 break;
 319         case FORMAT_SUBST_SYS:
 320                 l = strpcpy(&s, l, "/sys");
 321                 break;
 322         case FORMAT_SUBST_ENV:
 323                 if (!attr)
 324                         goto null_terminate;
 325                 r = sd_device_get_property_value(dev, attr, &val);
 326                 if (r == -ENOENT)
 327                         goto null_terminate;
 328                 if (r < 0)
 329                         return r;
 330                 l = strpcpy(&s, l, val);
 331                 break;
 332         default:
 333                 assert_not_reached("Unknown format substitution type");
 334         }
 335
 336         return s - dest;
 337
 338 null_terminate:
 339         *s = '\0';
 340         return 0;
 341 }
 342
 343 ssize_t udev_event_apply_format(UdevEvent *event,
 344                                 const char *src, char *dest, size_t size,
 345                                 bool replace_whitespace) {
 346         const char *from;
 347         char *s;
 348         size_t l;
 349
 350         assert(event);
 351         assert(event->dev);
 352         assert(src);
 353         assert(dest);
 354         assert(size > 0);
 355
 356         from = src;
 357         s = dest;
 358         l = size;
 359
 360         for (;;) {
 361                 const struct subst_map_entry *entry = NULL;
 362                 char attrbuf[UTIL_PATH_SIZE], *attr;
 363                 bool format_dollar = false;
 364                 ssize_t subst_len;
 365
 366                 while (from[0] != '\0') {
 367                         if (from[0] == '$') {
 368                                 /* substitute named variable */
 369                                 unsigned i;
 370
 371                                 if (from[1] == '$') {
 372                                         from++;
 373                                         goto copy;
 374                                 }
 375
 376                                 for (i = 0; i < ELEMENTSOF(map); i++) {
 377                                         if (startswith(&from[1], map[i].name)) {
 378                                                 entry = &map[i];
 379                                                 from += strlen(map[i].name)+1;
 380                                                 format_dollar = true;
 381                                                 goto subst;
 382                                         }
 383                                 }
 384                         } else if (from[0] == '%') {
 385                                 /* substitute format char */
 386                                 unsigned i;
 387
 388                                 if (from[1] == '%') {
 389                                         from++;
 390                                         goto copy;
 391                                 }
 392
 393                                 for (i = 0; i < ELEMENTSOF(map); i++) {
 394                                         if (from[1] == map[i].fmt) {
 395                                                 entry = &map[i];
 396                                                 from += 2;
 397                                                 goto subst;
 398                                         }
 399                                 }
 400                         }
 401 copy:
 402                         /* copy char */
 403                         if (l < 2) /* need space for this char and the terminating NUL */
 404                                 goto out;
 405                         s[0] = from[0];
 406                         from++;
 407                         s++;
 408                         l--;
 409                 }
 410
 411                 goto out;
 412 subst:
 413                 /* extract possible $format{attr} */
 414                 if (from[0] == '{') {
 415                         unsigned i;
 416
 417                         from++;
 418                         for (i = 0; from[i] != '}'; i++)
 419                                 if (from[i] == '\0') {
 420                                         log_error("missing closing brace for format '%s'", src);
 421                                         goto out;
 422                                 }
 423
 424                         if (i >= sizeof(attrbuf))
 425                                 goto out;
 426                         memcpy(attrbuf, from, i);
 427                         attrbuf[i] = '\0';
 428                         from += i+1;
 429                         attr = attrbuf;
 430                 } else
 431                         attr = NULL;
 432
 433                 subst_len = udev_event_subst_format(event, entry->type, attr, s, l);
 434                 if (subst_len < 0) {
 435                         if (format_dollar)
 436                                 log_device_warning_errno(event->dev, subst_len, "Failed to substitute variable '$%s', ignoring: %m", entry->name);
 437                         else
 438                                 log_device_warning_errno(event->dev, subst_len, "Failed to apply format '%%%c', ignoring: %m", entry->fmt);
 439
 440                         continue;
 441                 }
 442
 443                 /* FORMAT_SUBST_RESULT handles spaces itself */
 444                 if (replace_whitespace && entry->type != FORMAT_SUBST_RESULT)
 445                         /* util_replace_whitespace can replace in-place,
 446                          * and does nothing if subst_len == 0
 447                          */
 448                         subst_len = util_replace_whitespace(s, s, subst_len);
 449
 450                 s += subst_len;
 451                 l -= subst_len;
 452         }
 453
 454 out:
 455         assert(l >= 1);
 456         s[0] = '\0';
 457         return l;
 458 }
 459
 460 static int on_spawn_io(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
 461         Spawn *spawn = userdata;
 462         char buf[4096], *p;
 463         size_t size;
 464         ssize_t l;
 465
 466         assert(spawn);
 467         assert(fd == spawn->fd_stdout || fd == spawn->fd_stderr);
 468         assert(!spawn->result || spawn->result_len < spawn->result_size);
 469
 470         if (fd == spawn->fd_stdout && spawn->result) {
 471                 p = spawn->result + spawn->result_len;
 472                 size = spawn->result_size - spawn->result_len;
 473         } else {
 474                 p = buf;
 475                 size = sizeof(buf);
 476         }
 477
 478         l = read(fd, p, size - 1);
 479         if (l < 0) {
 480                 if (errno != EAGAIN)
 481                         log_error_errno(errno, "Failed to read stdout of '%s': %m", spawn->cmd);
 482
 483                 return 0;
 484         }
 485
 486         p[l] = '\0';
 487         if (fd == spawn->fd_stdout && spawn->result)
 488                 spawn->result_len += l;
 489
 490         /* Log output only if we watch stderr. */
 491         if (l > 0 && spawn->fd_stderr >= 0) {
 492                 _cleanup_strv_free_ char **v = NULL;
 493                 char **q;
 494
 495                 v = strv_split_newlines(p);
 496                 if (!v)
 497                         return 0;
 498
 499                 STRV_FOREACH(q, v)
 500                         log_debug("'%s'(%s) '%s'", spawn->cmd,
 501                                   fd == spawn->fd_stdout ? "out" : "err", *q);
 502         }
 503
 504         return 0;
 505 }
 506
 507 static int on_spawn_timeout(sd_event_source *s, uint64_t usec, void *userdata) {
 508         Spawn *spawn = userdata;
 509         char timeout[FORMAT_TIMESPAN_MAX];
 510
 511         assert(spawn);
 512
 513         kill_and_sigcont(spawn->pid, SIGKILL);
 514
 515         log_error("Spawned process '%s' ["PID_FMT"] timed out after %s, killing", spawn->cmd, spawn->pid,
 516                   format_timespan(timeout, sizeof(timeout), spawn->timeout_usec, USEC_PER_SEC));
 517
 518         return 1;
 519 }
 520
 521 static int on_spawn_timeout_warning(sd_event_source *s, uint64_t usec, void *userdata) {
 522         Spawn *spawn = userdata;
 523         char timeout[FORMAT_TIMESPAN_MAX];
 524
 525         assert(spawn);
 526
 527         log_warning("Spawned process '%s' ["PID_FMT"] is taking longer than %s to complete", spawn->cmd, spawn->pid,
 528                     format_timespan(timeout, sizeof(timeout), spawn->timeout_warn_usec, USEC_PER_SEC));
 529
 530         return 1;
 531 }
 532
 533 static int on_spawn_sigchld(sd_event_source *s, const siginfo_t *si, void *userdata) {
 534         Spawn *spawn = userdata;
 535         int ret = -EIO;
 536
 537         assert(spawn);
 538
 539         switch (si->si_code) {
 540         case CLD_EXITED:
 541                 if (si->si_status == 0)
 542                         log_debug("Process '%s' succeeded.", spawn->cmd);
 543                 else
 544                         log_full(spawn->accept_failure ? LOG_DEBUG : LOG_WARNING,
 545                                  "Process '%s' failed with exit code %i.", spawn->cmd, si->si_status);
 546                 ret = si->si_status;
 547                 break;
 548         case CLD_KILLED:
 549         case CLD_DUMPED:
 550                 log_error("Process '%s' terminated by signal %s.", spawn->cmd, signal_to_string(si->si_status));
 551                 break;
 552         default:
 553                 log_error("Process '%s' failed due to unknown reason.", spawn->cmd);
 554         }
 555
 556         sd_event_exit(sd_event_source_get_event(s), ret);
 557         return 1;
 558 }
 559
 560 static int spawn_wait(Spawn *spawn) {
 561         _cleanup_(sd_event_unrefp) sd_event *e = NULL;
 562         int r;
 563
 564         assert(spawn);
 565
 566         r = sd_event_new(&e);
 567         if (r < 0)
 568                 return r;
 569
 570         if (spawn->timeout_usec > 0) {
 571                 usec_t usec, age_usec;
 572
 573                 usec = now(CLOCK_MONOTONIC);
 574                 age_usec = usec - spawn->event_birth_usec;
 575                 if (age_usec < spawn->timeout_usec) {
 576                         if (spawn->timeout_warn_usec > 0 &&
 577                             spawn->timeout_warn_usec < spawn->timeout_usec &&
 578                             spawn->timeout_warn_usec > age_usec) {
 579                                 spawn->timeout_warn_usec -= age_usec;
 580
 581                                 r = sd_event_add_time(e, NULL, CLOCK_MONOTONIC,
 582                                                       usec + spawn->timeout_warn_usec, USEC_PER_SEC,
 583                                                       on_spawn_timeout_warning, spawn);
 584                                 if (r < 0)
 585                                         return r;
 586                         }
 587
 588                         spawn->timeout_usec -= age_usec;
 589
 590                         r = sd_event_add_time(e, NULL, CLOCK_MONOTONIC,
 591                                               usec + spawn->timeout_usec, USEC_PER_SEC, on_spawn_timeout, spawn);
 592                         if (r < 0)
 593                                 return r;
 594                 }
 595         }
 596
 597         if (spawn->fd_stdout >= 0) {
 598                 r = sd_event_add_io(e, NULL, spawn->fd_stdout, EPOLLIN, on_spawn_io, spawn);
 599                 if (r < 0)
 600                         return r;
 601         }
 602
 603         if (spawn->fd_stderr >= 0) {
 604                 r = sd_event_add_io(e, NULL, spawn->fd_stderr, EPOLLIN, on_spawn_io, spawn);
 605                 if (r < 0)
 606                         return r;
 607         }
 608
 609         r = sd_event_add_child(e, NULL, spawn->pid, WEXITED, on_spawn_sigchld, spawn);
 610         if (r < 0)
 611                 return r;
 612
 613         return sd_event_loop(e);
 614 }
 615
 616 int udev_event_spawn(UdevEvent *event,
 617                      usec_t timeout_usec,
 618                      bool accept_failure,
 619                      const char *cmd,
 620                      char *result, size_t ressize) {
 621         _cleanup_close_pair_ int outpipe[2] = {-1, -1}, errpipe[2] = {-1, -1};
 622         _cleanup_strv_free_ char **argv = NULL;
 623         char **envp = NULL;
 624         Spawn spawn;
 625         pid_t pid;
 626         int r;
 627
 628         assert(event);
 629         assert(event->dev);
 630         assert(result || ressize == 0);
 631
 632         /* pipes from child to parent */
 633         if (result || log_get_max_level() >= LOG_INFO)
 634                 if (pipe2(outpipe, O_NONBLOCK|O_CLOEXEC) != 0)
 635                         return log_error_errno(errno, "Failed to create pipe for command '%s': %m", cmd);
 636
 637         if (log_get_max_level() >= LOG_INFO)
 638                 if (pipe2(errpipe, O_NONBLOCK|O_CLOEXEC) != 0)
 639                         return log_error_errno(errno, "Failed to create pipe for command '%s': %m", cmd);
 640
 641         argv = strv_split_full(cmd, NULL, SPLIT_QUOTES|SPLIT_RELAX);
 642         if (!argv)
 643                 return log_oom();
 644
 645         if (isempty(argv[0]))
 646                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
 647                                        "Invalid command '%s'", cmd);
 648
 649         /* allow programs in /usr/lib/udev/ to be called without the path */
 650         if (!path_is_absolute(argv[0])) {
 651                 char *program;
 652
 653                 program = path_join(UDEVLIBEXECDIR, argv[0]);
 654                 if (!program)
 655                         return log_oom();
 656
 657                 free_and_replace(argv[0], program);
 658         }
 659
 660         r = device_get_properties_strv(event->dev, &envp);
 661         if (r < 0)
 662                 return log_device_error_errno(event->dev, r, "Failed to get device properties");
 663
 664         log_debug("Starting '%s'", cmd);
 665
 666         r = safe_fork("(spawn)", FORK_RESET_SIGNALS|FORK_DEATHSIG|FORK_LOG, &pid);
 667         if (r < 0)
 668                 return log_error_errno(r, "Failed to fork() to execute command '%s': %m", cmd);
 669         if (r == 0) {
 670                 if (rearrange_stdio(-1, outpipe[WRITE_END], errpipe[WRITE_END]) < 0)
 671                         _exit(EXIT_FAILURE);
 672
 673                 (void) close_all_fds(NULL, 0);
 674                 (void) rlimit_nofile_safe();
 675
 676                 execve(argv[0], argv, envp);
 677                 _exit(EXIT_FAILURE);
 678         }
 679
 680         /* parent closed child's ends of pipes */
 681         outpipe[WRITE_END] = safe_close(outpipe[WRITE_END]);
 682         errpipe[WRITE_END] = safe_close(errpipe[WRITE_END]);
 683
 684         spawn = (Spawn) {
 685                 .cmd = cmd,
 686                 .pid = pid,
 687                 .accept_failure = accept_failure,
 688                 .timeout_warn_usec = udev_warn_timeout(timeout_usec),
 689                 .timeout_usec = timeout_usec,
 690                 .event_birth_usec = event->birth_usec,
 691                 .fd_stdout = outpipe[READ_END],
 692                 .fd_stderr = errpipe[READ_END],
 693                 .result = result,
 694                 .result_size = ressize,
 695         };
 696         r = spawn_wait(&spawn);
 697         if (r < 0)
 698                 return log_error_errno(r, "Failed to wait for spawned command '%s': %m", cmd);
 699
 700         if (result)
 701                 result[spawn.result_len] = '\0';
 702
 703         return r; /* 0 for success, and positive if the program failed */
 704 }
 705
 706 static int rename_netif(UdevEvent *event) {
 707         sd_device *dev = event->dev;
 708         const char *oldname;
 709         int ifindex, r;
 710
 711         if (!event->name)
 712                 return 0; /* No new name is requested. */
 713
 714         r = sd_device_get_sysname(dev, &oldname);
 715         if (r < 0)
 716                 return log_device_error_errno(dev, r, "Failed to get sysname: %m");
 717
 718         if (streq(event->name, oldname))
 719                 return 0; /* The interface name is already requested name. */
 720
 721         if (!device_for_action(dev, DEVICE_ACTION_ADD))
 722                 return 0; /* Rename the interface only when it is added. */
 723
 724         r = sd_device_get_ifindex(dev, &ifindex);
 725         if (r == -ENOENT)
 726                 return 0; /* Device is not a network interface. */
 727         if (r < 0)
 728                 return log_device_error_errno(dev, r, "Failed to get ifindex: %m");
 729
 730         r = rtnl_set_link_name(&event->rtnl, ifindex, event->name);
 731         if (r < 0)
 732                 return log_device_error_errno(dev, r, "Failed to rename network interface %i from '%s' to '%s': %m",
 733                                               ifindex, oldname, event->name);
 734
 735         /* Set ID_RENAMING boolean property here, and drop it in the corresponding move uevent later. */
 736         r = device_add_property(dev, "ID_RENAMING", "1");
 737         if (r < 0)
 738                 log_device_warning_errno(dev, r, "Failed to add 'ID_RENAMING' property: %m");
 739
 740         r = device_rename(dev, event->name);
 741         if (r < 0)
 742                 log_device_warning_errno(dev, r, "Failed to update properties with new name '%s': %m", event->name);
 743
 744         log_device_debug(dev, "Network interface %i is renamed from '%s' to '%s'", ifindex, oldname, event->name);
 745
 746         return 1;
 747 }
 748
 749 static int update_devnode(UdevEvent *event) {
 750         sd_device *dev = event->dev;
 751         bool apply;
 752         int r;
 753
 754         r = sd_device_get_devnum(dev, NULL);
 755         if (r == -ENOENT)
 756                 return 0;
 757         if (r < 0)
 758                 return log_device_error_errno(dev, r, "Failed to get devnum: %m");
 759
 760         /* remove/update possible left-over symlinks from old database entry */
 761         if (event->dev_db_clone)
 762                 (void) udev_node_update_old_links(dev, event->dev_db_clone);
 763
 764         if (!uid_is_valid(event->uid)) {
 765                 r = device_get_devnode_uid(dev, &event->uid);
 766                 if (r == -ENOENT)
 767                         event->uid = 0;
 768                 else if (r < 0)
 769                         return log_device_error_errno(dev, r, "Failed to get devnode UID: %m");
 770         }
 771
 772         if (!gid_is_valid(event->gid)) {
 773                 r = device_get_devnode_gid(dev, &event->gid);
 774                 if (r == -ENOENT)
 775                         event->gid = 0;
 776                 else if (r < 0)
 777                         return log_device_error_errno(dev, r, "Failed to get devnode GID: %m");
 778         }
 779
 780         if (event->mode == MODE_INVALID) {
 781                 r = device_get_devnode_mode(dev, &event->mode);
 782                 if (r < 0 && r != -ENOENT)
 783                         return log_device_error_errno(dev, r, "Failed to get devnode mode: %m");
 784                 if (r == -ENOENT) {
 785                         if (event->gid > 0)
 786                                 /* default 0660 if a group is assigned */
 787                                 event->mode = 0660;
 788                         else
 789                                 /* default 0600 */
 790                                 event->mode = 0600;
 791                 }
 792         }
 793
 794         apply = device_for_action(dev, DEVICE_ACTION_ADD) ||
 795                 uid_is_valid(event->uid) ||
 796                 gid_is_valid(event->gid) ||
 797                 event->mode != MODE_INVALID;
 798         return udev_node_add(dev, apply, event->mode, event->uid, event->gid, event->seclabel_list);
 799 }
 800
 801 static void event_execute_rules_on_remove(
 802                 UdevEvent *event,
 803                 usec_t timeout_usec,
 804                 Hashmap *properties_list,
 805                 UdevRules *rules) {
 806
 807         sd_device *dev = event->dev;
 808         int r;
 809
 810         r = device_read_db_internal(dev, true);
 811         if (r < 0)
 812                 log_device_debug_errno(dev, r, "Failed to read database under /run/udev/data/: %m");
 813
 814         r = device_tag_index(dev, NULL, false);
 815         if (r < 0)
 816                 log_device_debug_errno(dev, r, "Failed to remove corresponding tag files under /run/udev/tag/, ignoring: %m");
 817
 818         r = device_delete_db(dev);
 819         if (r < 0)
 820                 log_device_debug_errno(dev, r, "Failed to delete database under /run/udev/data/, ignoring: %m");
 821
 822         if (sd_device_get_devnum(dev, NULL) >= 0)
 823                 (void) udev_watch_end(dev);
 824
 825         (void) udev_rules_apply_to_event(rules, event, timeout_usec, properties_list);
 826
 827         if (sd_device_get_devnum(dev, NULL) >= 0)
 828                 (void) udev_node_remove(dev);
 829 }
 830
 831 static int udev_event_on_move(UdevEvent *event) {
 832         sd_device *dev = event->dev;
 833         int r;
 834
 835         if (event->dev_db_clone &&
 836             sd_device_get_devnum(dev, NULL) < 0) {
 837                 r = device_copy_properties(dev, event->dev_db_clone);
 838                 if (r < 0)
 839                         log_device_debug_errno(dev, r, "Failed to copy properties from cloned sd_device object, ignoring: %m");
 840         }
 841
 842         /* Drop previously added property */
 843         r = device_add_property(dev, "ID_RENAMING", NULL);
 844         if (r < 0)
 845                 return log_device_debug_errno(dev, r, "Failed to remove 'ID_RENAMING' property, ignoring: %m");
 846
 847         return 0;
 848 }
 849
 850 int udev_event_execute_rules(UdevEvent *event,
 851                              usec_t timeout_usec,
 852                              Hashmap *properties_list,
 853                              UdevRules *rules) {
 854         const char *subsystem;
 855         DeviceAction action;
 856         sd_device *dev;
 857         int r;
 858
 859         assert(event);
 860         assert(rules);
 861
 862         dev = event->dev;
 863
 864         r = sd_device_get_subsystem(dev, &subsystem);
 865         if (r < 0)
 866                 return log_device_error_errno(dev, r, "Failed to get subsystem: %m");
 867
 868         r = device_get_action(dev, &action);
 869         if (r < 0)
 870                 return log_device_error_errno(dev, r, "Failed to get ACTION: %m");
 871
 872         if (action == DEVICE_ACTION_REMOVE) {
 873                 event_execute_rules_on_remove(event, timeout_usec, properties_list, rules);
 874                 return 0;
 875         }
 876
 877         r = device_clone_with_db(dev, &event->dev_db_clone);
 878         if (r < 0)
 879                 log_device_debug_errno(dev, r, "Failed to clone sd_device object, ignoring: %m");
 880
 881         if (event->dev_db_clone && sd_device_get_devnum(dev, NULL) >= 0)
 882                 /* Disable watch during event processing. */
 883                 (void) udev_watch_end(event->dev_db_clone);
 884
 885         if (action == DEVICE_ACTION_MOVE)
 886                 (void) udev_event_on_move(event);
 887
 888         (void) udev_rules_apply_to_event(rules, event, timeout_usec, properties_list);
 889
 890         (void) rename_netif(event);
 891         (void) update_devnode(event);
 892
 893         /* preserve old, or get new initialization timestamp */
 894         r = device_ensure_usec_initialized(dev, event->dev_db_clone);
 895         if (r < 0)
 896                 log_device_debug_errno(dev, r, "Failed to set initialization timestamp, ignoring: %m");
 897
 898         /* (re)write database file */
 899         r = device_tag_index(dev, event->dev_db_clone, true);
 900         if (r < 0)
 901                 log_device_debug_errno(dev, r, "Failed to update tags under /run/udev/tag/, ignoring: %m");
 902
 903         r = device_update_db(dev);
 904         if (r < 0)
 905                 log_device_debug_errno(dev, r, "Failed to update database under /run/udev/data/, ignoring: %m");
 906
 907         device_set_is_initialized(dev);
 908
 909         event->dev_db_clone = sd_device_unref(event->dev_db_clone);
 910
 911         return 0;
 912 }
 913
 914 void udev_event_execute_run(UdevEvent *event, usec_t timeout_usec) {
 915         const char *cmd;
 916         void *val;
 917         Iterator i;
 918         int r;
 919
 920         ORDERED_HASHMAP_FOREACH_KEY(val, cmd, event->run_list, i) {
 921                 UdevBuiltinCommand builtin_cmd = PTR_TO_UDEV_BUILTIN_CMD(val);
 922                 char command[UTIL_PATH_SIZE];
 923
 924                 (void) udev_event_apply_format(event, cmd, command, sizeof(command), false);
 925
 926                 if (builtin_cmd != _UDEV_BUILTIN_INVALID) {
 927                         log_device_debug(event->dev, "Running built-in command \"%s\"", command);
 928                         r = udev_builtin_run(event->dev, builtin_cmd, command, false);
 929                         if (r < 0)
 930                                 log_device_debug_errno(event->dev, r, "Failed to run built-in command \"%s\", ignoring: %m", command);
 931                 } else {
 932                         if (event->exec_delay_usec > 0) {
 933                                 char buf[FORMAT_TIMESPAN_MAX];
 934
 935                                 log_device_debug(event->dev, "Delaying execution of \"%s\" for %s.",
 936                                                  command, format_timespan(buf, sizeof(buf), event->exec_delay_usec, USEC_PER_SEC));
 937                                 (void) usleep(event->exec_delay_usec);
 938                         }
 939
 940                         log_device_debug(event->dev, "Running command \"%s\"", command);
 941                         r = udev_event_spawn(event, timeout_usec, false, command, NULL, 0);
 942                         if (r > 0) /* returned value is positive when program fails */
 943                                 log_device_debug(event->dev, "Command \"%s\" returned %d (error), ignoring.", command, r);
 944                 }
 945         }
 946 }