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 "parse-util.h"
  24 #include "path-util.h"
  25 #include "process-util.h"
  26 #include "rlimit-util.h"
  27 #include "signal-util.h"
  28 #include "stdio-util.h"
  29 #include "string-util.h"
  30 #include "strv.h"
  31 #include "strxcpyx.h"
  32 #include "udev-builtin.h"
  33 #include "udev-event.h"
  34 #include "udev-node.h"
  35 #include "udev-util.h"
  36 #include "udev-watch.h"
  37 #include "user-util.h"
  38
  39 typedef struct Spawn {
  40         const char *cmd;
  41         pid_t pid;
  42         usec_t timeout_warn_usec;
  43         usec_t timeout_usec;
  44         usec_t event_birth_usec;
  45         bool accept_failure;
  46         int fd_stdout;
  47         int fd_stderr;
  48         char *result;
  49         size_t result_size;
  50         size_t result_len;
  51 } Spawn;
  52
  53 UdevEvent *udev_event_new(sd_device *dev, usec_t exec_delay_usec, sd_netlink *rtnl) {
  54         UdevEvent *event;
  55
  56         assert(dev);
  57
  58         event = new(UdevEvent, 1);
  59         if (!event)
  60                 return NULL;
  61
  62         *event = (UdevEvent) {
  63                 .dev = sd_device_ref(dev),
  64                 .birth_usec = now(CLOCK_MONOTONIC),
  65                 .exec_delay_usec = exec_delay_usec,
  66                 .rtnl = sd_netlink_ref(rtnl),
  67                 .uid = UID_INVALID,
  68                 .gid = GID_INVALID,
  69                 .mode = MODE_INVALID,
  70         };
  71
  72         return event;
  73 }
  74
  75 UdevEvent *udev_event_free(UdevEvent *event) {
  76         if (!event)
  77                 return NULL;
  78
  79         sd_device_unref(event->dev);
  80         sd_device_unref(event->dev_db_clone);
  81         sd_netlink_unref(event->rtnl);
  82         ordered_hashmap_free_free_key(event->run_list);
  83         ordered_hashmap_free_free_free(event->seclabel_list);
  84         free(event->program_result);
  85         free(event->name);
  86
  87         return mfree(event);
  88 }
  89
  90 typedef enum {
  91         FORMAT_SUBST_DEVNODE,
  92         FORMAT_SUBST_ATTR,
  93         FORMAT_SUBST_ENV,
  94         FORMAT_SUBST_KERNEL,
  95         FORMAT_SUBST_KERNEL_NUMBER,
  96         FORMAT_SUBST_DRIVER,
  97         FORMAT_SUBST_DEVPATH,
  98         FORMAT_SUBST_ID,
  99         FORMAT_SUBST_MAJOR,
 100         FORMAT_SUBST_MINOR,
 101         FORMAT_SUBST_RESULT,
 102         FORMAT_SUBST_PARENT,
 103         FORMAT_SUBST_NAME,
 104         FORMAT_SUBST_LINKS,
 105         FORMAT_SUBST_ROOT,
 106         FORMAT_SUBST_SYS,
 107         _FORMAT_SUBST_TYPE_MAX,
 108         _FORMAT_SUBST_TYPE_INVALID = -1
 109 } FormatSubstitutionType;
 110
 111 struct subst_map_entry {
 112         const char *name;
 113         const char fmt;
 114         FormatSubstitutionType type;
 115 };
 116
 117 static const struct subst_map_entry map[] = {
 118            { .name = "devnode",  .fmt = 'N', .type = FORMAT_SUBST_DEVNODE },
 119            { .name = "tempnode", .fmt = 'N', .type = FORMAT_SUBST_DEVNODE }, /* deprecated */
 120            { .name = "attr",     .fmt = 's', .type = FORMAT_SUBST_ATTR },
 121            { .name = "sysfs",    .fmt = 's', .type = FORMAT_SUBST_ATTR }, /* deprecated */
 122            { .name = "env",      .fmt = 'E', .type = FORMAT_SUBST_ENV },
 123            { .name = "kernel",   .fmt = 'k', .type = FORMAT_SUBST_KERNEL },
 124            { .name = "number",   .fmt = 'n', .type = FORMAT_SUBST_KERNEL_NUMBER },
 125            { .name = "driver",   .fmt = 'd', .type = FORMAT_SUBST_DRIVER },
 126            { .name = "devpath",  .fmt = 'p', .type = FORMAT_SUBST_DEVPATH },
 127            { .name = "id",       .fmt = 'b', .type = FORMAT_SUBST_ID },
 128            { .name = "major",    .fmt = 'M', .type = FORMAT_SUBST_MAJOR },
 129            { .name = "minor",    .fmt = 'm', .type = FORMAT_SUBST_MINOR },
 130            { .name = "result",   .fmt = 'c', .type = FORMAT_SUBST_RESULT },
 131            { .name = "parent",   .fmt = 'P', .type = FORMAT_SUBST_PARENT },
 132            { .name = "name",     .fmt = 'D', .type = FORMAT_SUBST_NAME },
 133            { .name = "links",    .fmt = 'L', .type = FORMAT_SUBST_LINKS },
 134            { .name = "root",     .fmt = 'r', .type = FORMAT_SUBST_ROOT },
 135            { .name = "sys",      .fmt = 'S', .type = FORMAT_SUBST_SYS },
 136 };
 137
 138 static const char *format_type_to_string(FormatSubstitutionType t) {
 139         for (size_t i = 0; i < ELEMENTSOF(map); i++)
 140                 if (map[i].type == t)
 141                         return map[i].name;
 142         return NULL;
 143 }
 144
 145 static char format_type_to_char(FormatSubstitutionType t) {
 146         for (size_t i = 0; i < ELEMENTSOF(map); i++)
 147                 if (map[i].type == t)
 148                         return map[i].fmt;
 149         return '\0';
 150 }
 151
 152 static int get_subst_type(const char **str, bool strict, FormatSubstitutionType *ret_type, char ret_attr[static UTIL_PATH_SIZE]) {
 153         const char *p = *str, *q = NULL;
 154         size_t i;
 155
 156         assert(str);
 157         assert(*str);
 158         assert(ret_type);
 159
 160         if (*p == '$') {
 161                 p++;
 162                 if (*p == '$') {
 163                         *str = p;
 164                         return 0;
 165                 }
 166                 for (i = 0; i < ELEMENTSOF(map); i++)
 167                         if ((q = startswith(p, map[i].name)))
 168                                 break;
 169         } else if (*p == '%') {
 170                 p++;
 171                 if (*p == '%') {
 172                         *str = p;
 173                         return 0;
 174                 }
 175
 176                 for (i = 0; i < ELEMENTSOF(map); i++)
 177                         if (*p == map[i].fmt) {
 178                                 q = p + 1;
 179                                 break;
 180                         }
 181         } else
 182                 return 0;
 183         if (!q)
 184                 /* When 'strict' flag is set, then '$' and '%' must be escaped. */
 185                 return strict ? -EINVAL : 0;
 186
 187         if (*q == '{') {
 188                 const char *start, *end;
 189                 size_t len;
 190
 191                 start = q + 1;
 192                 end = strchr(start, '}');
 193                 if (!end)
 194                         return -EINVAL;
 195
 196                 len = end - start;
 197                 if (len == 0 || len >= UTIL_PATH_SIZE)
 198                         return -EINVAL;
 199
 200                 strnscpy(ret_attr, UTIL_PATH_SIZE, start, len);
 201                 q = end + 1;
 202         } else
 203                 *ret_attr = '\0';
 204
 205         *str = q;
 206         *ret_type = map[i].type;
 207         return 1;
 208 }
 209
 210 static int safe_atou_optional_plus(const char *s, unsigned *ret) {
 211         const char *p;
 212         int r;
 213
 214         assert(s);
 215         assert(ret);
 216
 217         /* Returns 1 if plus, 0 if no plus, negative on error */
 218
 219         p = endswith(s, "+");
 220         if (p)
 221                 s = strndupa(s, p - s);
 222
 223         r = safe_atou(s, ret);
 224         if (r < 0)
 225                 return r;
 226
 227         return !!p;
 228 }
 229
 230 static ssize_t udev_event_subst_format(
 231                 UdevEvent *event,
 232                 FormatSubstitutionType type,
 233                 const char *attr,
 234                 char *dest,
 235                 size_t l) {
 236         sd_device *parent, *dev = event->dev;
 237         const char *val = NULL;
 238         char *s = dest;
 239         int r;
 240
 241         switch (type) {
 242         case FORMAT_SUBST_DEVPATH:
 243                 r = sd_device_get_devpath(dev, &val);
 244                 if (r < 0)
 245                         return r;
 246                 l = strpcpy(&s, l, val);
 247                 break;
 248         case FORMAT_SUBST_KERNEL:
 249                 r = sd_device_get_sysname(dev, &val);
 250                 if (r < 0)
 251                         return r;
 252                 l = strpcpy(&s, l, val);
 253                 break;
 254         case FORMAT_SUBST_KERNEL_NUMBER:
 255                 r = sd_device_get_sysnum(dev, &val);
 256                 if (r == -ENOENT)
 257                         goto null_terminate;
 258                 if (r < 0)
 259                         return r;
 260                 l = strpcpy(&s, l, val);
 261                 break;
 262         case FORMAT_SUBST_ID:
 263                 if (!event->dev_parent)
 264                         goto null_terminate;
 265                 r = sd_device_get_sysname(event->dev_parent, &val);
 266                 if (r < 0)
 267                         return r;
 268                 l = strpcpy(&s, l, val);
 269                 break;
 270         case FORMAT_SUBST_DRIVER:
 271                 if (!event->dev_parent)
 272                         goto null_terminate;
 273                 r = sd_device_get_driver(event->dev_parent, &val);
 274                 if (r == -ENOENT)
 275                         goto null_terminate;
 276                 if (r < 0)
 277                         return r;
 278                 l = strpcpy(&s, l, val);
 279                 break;
 280         case FORMAT_SUBST_MAJOR:
 281         case FORMAT_SUBST_MINOR: {
 282                 dev_t devnum;
 283
 284                 r = sd_device_get_devnum(dev, &devnum);
 285                 if (r < 0 && r != -ENOENT)
 286                         return r;
 287                 l = strpcpyf(&s, l, "%u", r < 0 ? 0 : type == FORMAT_SUBST_MAJOR ? major(devnum) : minor(devnum));
 288                 break;
 289         }
 290         case FORMAT_SUBST_RESULT: {
 291                 unsigned index = 0; /* 0 means whole string */
 292                 bool has_plus;
 293
 294                 if (!event->program_result)
 295                         goto null_terminate;
 296
 297                 if (!isempty(attr)) {
 298                         r = safe_atou_optional_plus(attr, &index);
 299                         if (r < 0)
 300                                 return r;
 301
 302                         has_plus = r;
 303                 }
 304
 305                 if (index == 0)
 306                         l = strpcpy(&s, l, event->program_result);
 307                 else {
 308                         const char *start, *p;
 309                         unsigned i;
 310
 311                         p = skip_leading_chars(event->program_result, NULL);
 312
 313                         for (i = 1; i < index; i++) {
 314                                 while (*p && !strchr(WHITESPACE, *p))
 315                                         p++;
 316                                 p = skip_leading_chars(p, NULL);
 317                                 if (*p == '\0')
 318                                         break;
 319                         }
 320                         if (i != index) {
 321                                 log_device_debug(dev, "requested part of result string not found");
 322                                 goto null_terminate;
 323                         }
 324
 325                         start = p;
 326                         /* %c{2+} copies the whole string from the second part on */
 327                         if (has_plus)
 328                                 l = strpcpy(&s, l, start);
 329                         else {
 330                                 while (*p && !strchr(WHITESPACE, *p))
 331                                         p++;
 332                                 l = strnpcpy(&s, l, start, p - start);
 333                         }
 334                 }
 335                 break;
 336         }
 337         case FORMAT_SUBST_ATTR: {
 338                 char vbuf[UTIL_NAME_SIZE];
 339                 int count;
 340
 341                 if (isempty(attr))
 342                         return -EINVAL;
 343
 344                 /* try to read the value specified by "[dmi/id]product_name" */
 345                 if (util_resolve_subsys_kernel(attr, vbuf, sizeof(vbuf), true) == 0)
 346                         val = vbuf;
 347
 348                 /* try to read the attribute the device */
 349                 if (!val)
 350                         (void) sd_device_get_sysattr_value(dev, attr, &val);
 351
 352                 /* try to read the attribute of the parent device, other matches have selected */
 353                 if (!val && event->dev_parent && event->dev_parent != dev)
 354                         (void) sd_device_get_sysattr_value(event->dev_parent, attr, &val);
 355
 356                 if (!val)
 357                         goto null_terminate;
 358
 359                 /* strip trailing whitespace, and replace unwanted characters */
 360                 if (val != vbuf)
 361                         strscpy(vbuf, sizeof(vbuf), val);
 362                 delete_trailing_chars(vbuf, NULL);
 363                 count = util_replace_chars(vbuf, UDEV_ALLOWED_CHARS_INPUT);
 364                 if (count > 0)
 365                         log_device_debug(dev, "%i character(s) replaced", count);
 366                 l = strpcpy(&s, l, vbuf);
 367                 break;
 368         }
 369         case FORMAT_SUBST_PARENT:
 370                 r = sd_device_get_parent(dev, &parent);
 371                 if (r == -ENODEV)
 372                         goto null_terminate;
 373                 if (r < 0)
 374                         return r;
 375                 r = sd_device_get_devname(parent, &val);
 376                 if (r == -ENOENT)
 377                         goto null_terminate;
 378                 if (r < 0)
 379                         return r;
 380                 l = strpcpy(&s, l, val + STRLEN("/dev/"));
 381                 break;
 382         case FORMAT_SUBST_DEVNODE:
 383                 r = sd_device_get_devname(dev, &val);
 384                 if (r == -ENOENT)
 385                         goto null_terminate;
 386                 if (r < 0)
 387                         return r;
 388                 l = strpcpy(&s, l, val);
 389                 break;
 390         case FORMAT_SUBST_NAME:
 391                 if (event->name)
 392                         l = strpcpy(&s, l, event->name);
 393                 else if (sd_device_get_devname(dev, &val) >= 0)
 394                         l = strpcpy(&s, l, val + STRLEN("/dev/"));
 395                 else {
 396                         r = sd_device_get_sysname(dev, &val);
 397                         if (r < 0)
 398                                 return r;
 399                         l = strpcpy(&s, l, val);
 400                 }
 401                 break;
 402         case FORMAT_SUBST_LINKS:
 403                 FOREACH_DEVICE_DEVLINK(dev, val)
 404                         if (s == dest)
 405                                 l = strpcpy(&s, l, val + STRLEN("/dev/"));
 406                         else
 407                                 l = strpcpyl(&s, l, " ", val + STRLEN("/dev/"), NULL);
 408                 if (s == dest)
 409                         goto null_terminate;
 410                 break;
 411         case FORMAT_SUBST_ROOT:
 412                 l = strpcpy(&s, l, "/dev");
 413                 break;
 414         case FORMAT_SUBST_SYS:
 415                 l = strpcpy(&s, l, "/sys");
 416                 break;
 417         case FORMAT_SUBST_ENV:
 418                 if (isempty(attr))
 419                         return -EINVAL;
 420                 r = sd_device_get_property_value(dev, attr, &val);
 421                 if (r == -ENOENT)
 422                         goto null_terminate;
 423                 if (r < 0)
 424                         return r;
 425                 l = strpcpy(&s, l, val);
 426                 break;
 427         default:
 428                 assert_not_reached("Unknown format substitution type");
 429         }
 430
 431         return s - dest;
 432
 433 null_terminate:
 434         *s = '\0';
 435         return 0;
 436 }
 437
 438 ssize_t udev_event_apply_format(UdevEvent *event,
 439                                 const char *src, char *dest, size_t size,
 440                                 bool replace_whitespace) {
 441         const char *s = src;
 442         int r;
 443
 444         assert(event);
 445         assert(event->dev);
 446         assert(src);
 447         assert(dest);
 448         assert(size > 0);
 449
 450         while (*s) {
 451                 FormatSubstitutionType type;
 452                 char attr[UTIL_PATH_SIZE];
 453                 ssize_t subst_len;
 454
 455                 r = get_subst_type(&s, false, &type, attr);
 456                 if (r < 0)
 457                         return log_device_warning_errno(event->dev, r, "Invalid format string, ignoring: %s", src);
 458                 if (r == 0) {
 459                         if (size < 2) /* need space for this char and the terminating NUL */
 460                                 break;
 461                         *dest++ = *s++;
 462                         size--;
 463                         continue;
 464                 }
 465
 466                 subst_len = udev_event_subst_format(event, type, attr, dest, size);
 467                 if (subst_len < 0)
 468                         return log_device_warning_errno(event->dev, subst_len,
 469                                                         "Failed to substitute variable '$%s' or apply format '%%%c', ignoring: %m",
 470                                                         format_type_to_string(type), format_type_to_char(type));
 471
 472                 /* FORMAT_SUBST_RESULT handles spaces itself */
 473                 if (replace_whitespace && type != FORMAT_SUBST_RESULT)
 474                         /* util_replace_whitespace can replace in-place,
 475                          * and does nothing if subst_len == 0 */
 476                         subst_len = util_replace_whitespace(dest, dest, subst_len);
 477
 478                 dest += subst_len;
 479                 size -= subst_len;
 480         }
 481
 482         assert(size >= 1);
 483         *dest = '\0';
 484         return size;
 485 }
 486
 487 int udev_check_format(const char *value, size_t *offset, const char **hint) {
 488         FormatSubstitutionType type;
 489         const char *s = value;
 490         char attr[UTIL_PATH_SIZE];
 491         int r;
 492
 493         while (*s) {
 494                 r = get_subst_type(&s, true, &type, attr);
 495                 if (r < 0) {
 496                         if (offset)
 497                                 *offset = s - value;
 498                         if (hint)
 499                                 *hint = "invalid substitution type";
 500                         return r;
 501                 } else if (r == 0) {
 502                         s++;
 503                         continue;
 504                 }
 505
 506                 if (IN_SET(type, FORMAT_SUBST_ATTR, FORMAT_SUBST_ENV) && isempty(attr)) {
 507                         if (offset)
 508                                 *offset = s - value;
 509                         if (hint)
 510                                 *hint = "attribute value missing";
 511                         return -EINVAL;
 512                 }
 513
 514                 if (type == FORMAT_SUBST_RESULT && !isempty(attr)) {
 515                         unsigned i;
 516
 517                         r = safe_atou_optional_plus(attr, &i);
 518                         if (r < 0) {
 519                                 if (offset)
 520                                         *offset = s - value;
 521                                 if (hint)
 522                                         *hint = "attribute value not a valid number";
 523                                 return r;
 524                         }
 525                 }
 526         }
 527
 528         return 0;
 529 }
 530
 531 static int on_spawn_io(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
 532         Spawn *spawn = userdata;
 533         char buf[4096], *p;
 534         size_t size;
 535         ssize_t l;
 536
 537         assert(spawn);
 538         assert(fd == spawn->fd_stdout || fd == spawn->fd_stderr);
 539         assert(!spawn->result || spawn->result_len < spawn->result_size);
 540
 541         if (fd == spawn->fd_stdout && spawn->result) {
 542                 p = spawn->result + spawn->result_len;
 543                 size = spawn->result_size - spawn->result_len;
 544         } else {
 545                 p = buf;
 546                 size = sizeof(buf);
 547         }
 548
 549         l = read(fd, p, size - 1);
 550         if (l < 0) {
 551                 if (errno != EAGAIN)
 552                         log_error_errno(errno, "Failed to read stdout of '%s': %m", spawn->cmd);
 553
 554                 return 0;
 555         }
 556
 557         p[l] = '\0';
 558         if (fd == spawn->fd_stdout && spawn->result)
 559                 spawn->result_len += l;
 560
 561         /* Log output only if we watch stderr. */
 562         if (l > 0 && spawn->fd_stderr >= 0) {
 563                 _cleanup_strv_free_ char **v = NULL;
 564                 char **q;
 565
 566                 v = strv_split_newlines(p);
 567                 if (!v)
 568                         return 0;
 569
 570                 STRV_FOREACH(q, v)
 571                         log_debug("'%s'(%s) '%s'", spawn->cmd,
 572                                   fd == spawn->fd_stdout ? "out" : "err", *q);
 573         }
 574
 575         return 0;
 576 }
 577
 578 static int on_spawn_timeout(sd_event_source *s, uint64_t usec, void *userdata) {
 579         Spawn *spawn = userdata;
 580         char timeout[FORMAT_TIMESPAN_MAX];
 581
 582         assert(spawn);
 583
 584         kill_and_sigcont(spawn->pid, SIGKILL);
 585
 586         log_error("Spawned process '%s' ["PID_FMT"] timed out after %s, killing", spawn->cmd, spawn->pid,
 587                   format_timespan(timeout, sizeof(timeout), spawn->timeout_usec, USEC_PER_SEC));
 588
 589         return 1;
 590 }
 591
 592 static int on_spawn_timeout_warning(sd_event_source *s, uint64_t usec, void *userdata) {
 593         Spawn *spawn = userdata;
 594         char timeout[FORMAT_TIMESPAN_MAX];
 595
 596         assert(spawn);
 597
 598         log_warning("Spawned process '%s' ["PID_FMT"] is taking longer than %s to complete", spawn->cmd, spawn->pid,
 599                     format_timespan(timeout, sizeof(timeout), spawn->timeout_warn_usec, USEC_PER_SEC));
 600
 601         return 1;
 602 }
 603
 604 static int on_spawn_sigchld(sd_event_source *s, const siginfo_t *si, void *userdata) {
 605         Spawn *spawn = userdata;
 606         int ret = -EIO;
 607
 608         assert(spawn);
 609
 610         switch (si->si_code) {
 611         case CLD_EXITED:
 612                 if (si->si_status == 0)
 613                         log_debug("Process '%s' succeeded.", spawn->cmd);
 614                 else
 615                         log_full(spawn->accept_failure ? LOG_DEBUG : LOG_WARNING,
 616                                  "Process '%s' failed with exit code %i.", spawn->cmd, si->si_status);
 617                 ret = si->si_status;
 618                 break;
 619         case CLD_KILLED:
 620         case CLD_DUMPED:
 621                 log_error("Process '%s' terminated by signal %s.", spawn->cmd, signal_to_string(si->si_status));
 622                 break;
 623         default:
 624                 log_error("Process '%s' failed due to unknown reason.", spawn->cmd);
 625         }
 626
 627         sd_event_exit(sd_event_source_get_event(s), ret);
 628         return 1;
 629 }
 630
 631 static int spawn_wait(Spawn *spawn) {
 632         _cleanup_(sd_event_unrefp) sd_event *e = NULL;
 633         int r;
 634
 635         assert(spawn);
 636
 637         r = sd_event_new(&e);
 638         if (r < 0)
 639                 return r;
 640
 641         if (spawn->timeout_usec > 0) {
 642                 usec_t usec, age_usec;
 643
 644                 usec = now(CLOCK_MONOTONIC);
 645                 age_usec = usec - spawn->event_birth_usec;
 646                 if (age_usec < spawn->timeout_usec) {
 647                         if (spawn->timeout_warn_usec > 0 &&
 648                             spawn->timeout_warn_usec < spawn->timeout_usec &&
 649                             spawn->timeout_warn_usec > age_usec) {
 650                                 spawn->timeout_warn_usec -= age_usec;
 651
 652                                 r = sd_event_add_time(e, NULL, CLOCK_MONOTONIC,
 653                                                       usec + spawn->timeout_warn_usec, USEC_PER_SEC,
 654                                                       on_spawn_timeout_warning, spawn);
 655                                 if (r < 0)
 656                                         return r;
 657                         }
 658
 659                         spawn->timeout_usec -= age_usec;
 660
 661                         r = sd_event_add_time(e, NULL, CLOCK_MONOTONIC,
 662                                               usec + spawn->timeout_usec, USEC_PER_SEC, on_spawn_timeout, spawn);
 663                         if (r < 0)
 664                                 return r;
 665                 }
 666         }
 667
 668         if (spawn->fd_stdout >= 0) {
 669                 r = sd_event_add_io(e, NULL, spawn->fd_stdout, EPOLLIN, on_spawn_io, spawn);
 670                 if (r < 0)
 671                         return r;
 672         }
 673
 674         if (spawn->fd_stderr >= 0) {
 675                 r = sd_event_add_io(e, NULL, spawn->fd_stderr, EPOLLIN, on_spawn_io, spawn);
 676                 if (r < 0)
 677                         return r;
 678         }
 679
 680         r = sd_event_add_child(e, NULL, spawn->pid, WEXITED, on_spawn_sigchld, spawn);
 681         if (r < 0)
 682                 return r;
 683
 684         return sd_event_loop(e);
 685 }
 686
 687 int udev_event_spawn(UdevEvent *event,
 688                      usec_t timeout_usec,
 689                      bool accept_failure,
 690                      const char *cmd,
 691                      char *result, size_t ressize) {
 692         _cleanup_close_pair_ int outpipe[2] = {-1, -1}, errpipe[2] = {-1, -1};
 693         _cleanup_strv_free_ char **argv = NULL;
 694         char **envp = NULL;
 695         Spawn spawn;
 696         pid_t pid;
 697         int r;
 698
 699         assert(event);
 700         assert(event->dev);
 701         assert(result || ressize == 0);
 702
 703         /* pipes from child to parent */
 704         if (result || log_get_max_level() >= LOG_INFO)
 705                 if (pipe2(outpipe, O_NONBLOCK|O_CLOEXEC) != 0)
 706                         return log_error_errno(errno, "Failed to create pipe for command '%s': %m", cmd);
 707
 708         if (log_get_max_level() >= LOG_INFO)
 709                 if (pipe2(errpipe, O_NONBLOCK|O_CLOEXEC) != 0)
 710                         return log_error_errno(errno, "Failed to create pipe for command '%s': %m", cmd);
 711
 712         argv = strv_split_full(cmd, NULL, SPLIT_QUOTES|SPLIT_RELAX);
 713         if (!argv)
 714                 return log_oom();
 715
 716         if (isempty(argv[0]))
 717                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
 718                                        "Invalid command '%s'", cmd);
 719
 720         /* allow programs in /usr/lib/udev/ to be called without the path */
 721         if (!path_is_absolute(argv[0])) {
 722                 char *program;
 723
 724                 program = path_join(UDEVLIBEXECDIR, argv[0]);
 725                 if (!program)
 726                         return log_oom();
 727
 728                 free_and_replace(argv[0], program);
 729         }
 730
 731         r = device_get_properties_strv(event->dev, &envp);
 732         if (r < 0)
 733                 return log_device_error_errno(event->dev, r, "Failed to get device properties");
 734
 735         log_debug("Starting '%s'", cmd);
 736
 737         r = safe_fork("(spawn)", FORK_RESET_SIGNALS|FORK_DEATHSIG|FORK_LOG, &pid);
 738         if (r < 0)
 739                 return log_error_errno(r, "Failed to fork() to execute command '%s': %m", cmd);
 740         if (r == 0) {
 741                 if (rearrange_stdio(-1, outpipe[WRITE_END], errpipe[WRITE_END]) < 0)
 742                         _exit(EXIT_FAILURE);
 743
 744                 (void) close_all_fds(NULL, 0);
 745                 (void) rlimit_nofile_safe();
 746
 747                 execve(argv[0], argv, envp);
 748                 _exit(EXIT_FAILURE);
 749         }
 750
 751         /* parent closed child's ends of pipes */
 752         outpipe[WRITE_END] = safe_close(outpipe[WRITE_END]);
 753         errpipe[WRITE_END] = safe_close(errpipe[WRITE_END]);
 754
 755         spawn = (Spawn) {
 756                 .cmd = cmd,
 757                 .pid = pid,
 758                 .accept_failure = accept_failure,
 759                 .timeout_warn_usec = udev_warn_timeout(timeout_usec),
 760                 .timeout_usec = timeout_usec,
 761                 .event_birth_usec = event->birth_usec,
 762                 .fd_stdout = outpipe[READ_END],
 763                 .fd_stderr = errpipe[READ_END],
 764                 .result = result,
 765                 .result_size = ressize,
 766         };
 767         r = spawn_wait(&spawn);
 768         if (r < 0)
 769                 return log_error_errno(r, "Failed to wait for spawned command '%s': %m", cmd);
 770
 771         if (result)
 772                 result[spawn.result_len] = '\0';
 773
 774         return r; /* 0 for success, and positive if the program failed */
 775 }
 776
 777 static int rename_netif(UdevEvent *event) {
 778         sd_device *dev = event->dev;
 779         const char *oldname;
 780         int ifindex, r;
 781
 782         if (!event->name)
 783                 return 0; /* No new name is requested. */
 784
 785         r = sd_device_get_sysname(dev, &oldname);
 786         if (r < 0)
 787                 return log_device_error_errno(dev, r, "Failed to get sysname: %m");
 788
 789         if (streq(event->name, oldname))
 790                 return 0; /* The interface name is already requested name. */
 791
 792         if (!device_for_action(dev, DEVICE_ACTION_ADD))
 793                 return 0; /* Rename the interface only when it is added. */
 794
 795         r = sd_device_get_ifindex(dev, &ifindex);
 796         if (r == -ENOENT)
 797                 return 0; /* Device is not a network interface. */
 798         if (r < 0)
 799                 return log_device_error_errno(dev, r, "Failed to get ifindex: %m");
 800
 801         r = rtnl_set_link_name(&event->rtnl, ifindex, event->name);
 802         if (r < 0)
 803                 return log_device_error_errno(dev, r, "Failed to rename network interface %i from '%s' to '%s': %m",
 804                                               ifindex, oldname, event->name);
 805
 806         /* Set ID_RENAMING boolean property here, and drop it in the corresponding move uevent later. */
 807         r = device_add_property(dev, "ID_RENAMING", "1");
 808         if (r < 0)
 809                 return log_device_warning_errno(dev, r, "Failed to add 'ID_RENAMING' property: %m");
 810
 811         r = device_rename(dev, event->name);
 812         if (r < 0)
 813                 return log_device_warning_errno(dev, r, "Failed to update properties with new name '%s': %m", event->name);
 814
 815         log_device_debug(dev, "Network interface %i is renamed from '%s' to '%s'", ifindex, oldname, event->name);
 816
 817         return 1;
 818 }
 819
 820 static int update_devnode(UdevEvent *event) {
 821         sd_device *dev = event->dev;
 822         bool apply;
 823         int r;
 824
 825         r = sd_device_get_devnum(dev, NULL);
 826         if (r == -ENOENT)
 827                 return 0;
 828         if (r < 0)
 829                 return log_device_error_errno(dev, r, "Failed to get devnum: %m");
 830
 831         /* remove/update possible left-over symlinks from old database entry */
 832         if (event->dev_db_clone)
 833                 (void) udev_node_update_old_links(dev, event->dev_db_clone);
 834
 835         if (!uid_is_valid(event->uid)) {
 836                 r = device_get_devnode_uid(dev, &event->uid);
 837                 if (r == -ENOENT)
 838                         event->uid = 0;
 839                 else if (r < 0)
 840                         return log_device_error_errno(dev, r, "Failed to get devnode UID: %m");
 841         }
 842
 843         if (!gid_is_valid(event->gid)) {
 844                 r = device_get_devnode_gid(dev, &event->gid);
 845                 if (r == -ENOENT)
 846                         event->gid = 0;
 847                 else if (r < 0)
 848                         return log_device_error_errno(dev, r, "Failed to get devnode GID: %m");
 849         }
 850
 851         if (event->mode == MODE_INVALID) {
 852                 r = device_get_devnode_mode(dev, &event->mode);
 853                 if (r < 0 && r != -ENOENT)
 854                         return log_device_error_errno(dev, r, "Failed to get devnode mode: %m");
 855                 if (r == -ENOENT) {
 856                         if (event->gid > 0)
 857                                 /* default 0660 if a group is assigned */
 858                                 event->mode = 0660;
 859                         else
 860                                 /* default 0600 */
 861                                 event->mode = 0600;
 862                 }
 863         }
 864
 865         apply = device_for_action(dev, DEVICE_ACTION_ADD) ||
 866                 uid_is_valid(event->uid) ||
 867                 gid_is_valid(event->gid) ||
 868                 event->mode != MODE_INVALID;
 869         return udev_node_add(dev, apply, event->mode, event->uid, event->gid, event->seclabel_list);
 870 }
 871
 872 static void event_execute_rules_on_remove(
 873                 UdevEvent *event,
 874                 usec_t timeout_usec,
 875                 Hashmap *properties_list,
 876                 UdevRules *rules) {
 877
 878         sd_device *dev = event->dev;
 879         int r;
 880
 881         r = device_read_db_internal(dev, true);
 882         if (r < 0)
 883                 log_device_debug_errno(dev, r, "Failed to read database under /run/udev/data/: %m");
 884
 885         r = device_tag_index(dev, NULL, false);
 886         if (r < 0)
 887                 log_device_debug_errno(dev, r, "Failed to remove corresponding tag files under /run/udev/tag/, ignoring: %m");
 888
 889         r = device_delete_db(dev);
 890         if (r < 0)
 891                 log_device_debug_errno(dev, r, "Failed to delete database under /run/udev/data/, ignoring: %m");
 892
 893         if (sd_device_get_devnum(dev, NULL) >= 0)
 894                 (void) udev_watch_end(dev);
 895
 896         (void) udev_rules_apply_to_event(rules, event, timeout_usec, properties_list);
 897
 898         if (sd_device_get_devnum(dev, NULL) >= 0)
 899                 (void) udev_node_remove(dev);
 900 }
 901
 902 static int udev_event_on_move(UdevEvent *event) {
 903         sd_device *dev = event->dev;
 904         int r;
 905
 906         if (event->dev_db_clone &&
 907             sd_device_get_devnum(dev, NULL) < 0) {
 908                 r = device_copy_properties(dev, event->dev_db_clone);
 909                 if (r < 0)
 910                         log_device_debug_errno(dev, r, "Failed to copy properties from cloned sd_device object, ignoring: %m");
 911         }
 912
 913         /* Drop previously added property */
 914         r = device_add_property(dev, "ID_RENAMING", NULL);
 915         if (r < 0)
 916                 return log_device_debug_errno(dev, r, "Failed to remove 'ID_RENAMING' property: %m");
 917
 918         return 0;
 919 }
 920
 921 int udev_event_execute_rules(UdevEvent *event,
 922                              usec_t timeout_usec,
 923                              Hashmap *properties_list,
 924                              UdevRules *rules) {
 925         const char *subsystem;
 926         DeviceAction action;
 927         sd_device *dev;
 928         int r;
 929
 930         assert(event);
 931         assert(rules);
 932
 933         dev = event->dev;
 934
 935         r = sd_device_get_subsystem(dev, &subsystem);
 936         if (r < 0)
 937                 return log_device_error_errno(dev, r, "Failed to get subsystem: %m");
 938
 939         r = device_get_action(dev, &action);
 940         if (r < 0)
 941                 return log_device_error_errno(dev, r, "Failed to get ACTION: %m");
 942
 943         if (action == DEVICE_ACTION_REMOVE) {
 944                 event_execute_rules_on_remove(event, timeout_usec, properties_list, rules);
 945                 return 0;
 946         }
 947
 948         r = device_clone_with_db(dev, &event->dev_db_clone);
 949         if (r < 0)
 950                 return log_device_debug_errno(dev, r, "Failed to clone sd_device object: %m");
 951
 952         if (event->dev_db_clone && sd_device_get_devnum(dev, NULL) >= 0)
 953                 /* Disable watch during event processing. */
 954                 (void) udev_watch_end(event->dev_db_clone);
 955
 956         if (action == DEVICE_ACTION_MOVE) {
 957                 r = udev_event_on_move(event);
 958                 if (r < 0)
 959                         return r;
 960         }
 961
 962         r = udev_rules_apply_to_event(rules, event, timeout_usec, properties_list);
 963         if (r < 0)
 964                 return log_device_debug_errno(dev, r, "Failed to apply udev rules: %m");
 965
 966         r = rename_netif(event);
 967         if (r < 0)
 968                 return r;
 969
 970         r = update_devnode(event);
 971         if (r < 0)
 972                 return r;
 973
 974         /* preserve old, or get new initialization timestamp */
 975         r = device_ensure_usec_initialized(dev, event->dev_db_clone);
 976         if (r < 0)
 977                 return log_device_debug_errno(dev, r, "Failed to set initialization timestamp: %m");
 978
 979         /* (re)write database file */
 980         r = device_tag_index(dev, event->dev_db_clone, true);
 981         if (r < 0)
 982                 return log_device_debug_errno(dev, r, "Failed to update tags under /run/udev/tag/: %m");
 983
 984         r = device_update_db(dev);
 985         if (r < 0)
 986                 return log_device_debug_errno(dev, r, "Failed to update database under /run/udev/data/: %m");
 987
 988         device_set_is_initialized(dev);
 989
 990         event->dev_db_clone = sd_device_unref(event->dev_db_clone);
 991
 992         return 0;
 993 }
 994
 995 void udev_event_execute_run(UdevEvent *event, usec_t timeout_usec) {
 996         const char *command;
 997         void *val;
 998         Iterator i;
 999         int r;
1000
1001         ORDERED_HASHMAP_FOREACH_KEY(val, command, event->run_list, i) {
1002                 UdevBuiltinCommand builtin_cmd = PTR_TO_UDEV_BUILTIN_CMD(val);
1003
1004                 if (builtin_cmd != _UDEV_BUILTIN_INVALID) {
1005                         log_device_debug(event->dev, "Running built-in command \"%s\"", command);
1006                         r = udev_builtin_run(event->dev, builtin_cmd, command, false);
1007                         if (r < 0)
1008                                 log_device_debug_errno(event->dev, r, "Failed to run built-in command \"%s\", ignoring: %m", command);
1009                 } else {
1010                         if (event->exec_delay_usec > 0) {
1011                                 char buf[FORMAT_TIMESPAN_MAX];
1012
1013                                 log_device_debug(event->dev, "Delaying execution of \"%s\" for %s.",
1014                                                  command, format_timespan(buf, sizeof(buf), event->exec_delay_usec, USEC_PER_SEC));
1015                                 (void) usleep(event->exec_delay_usec);
1016                         }
1017
1018                         log_device_debug(event->dev, "Running command \"%s\"", command);
1019                         r = udev_event_spawn(event, timeout_usec, false, command, NULL, 0);
1020                         if (r > 0) /* returned value is positive when program fails */
1021                                 log_device_debug(event->dev, "Command \"%s\" returned %d (error), ignoring.", command, r);
1022                 }
1023         }
1024 }