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