src/udev/udev-event.c

   1 /*
   2  * Copyright (C) 2003-2013 Kay Sievers <kay@vrfy.org>
   3  *
   4  * This program is free software: you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #include <stdlib.h>
  19 #include <stdio.h>
  20 #include <stddef.h>
  21 #include <unistd.h>
  22 #include <fcntl.h>
  23 #include <errno.h>
  24 #include <ctype.h>
  25 #include <string.h>
  26 #include <net/if.h>
  27 #include <sys/prctl.h>
  28 #include <poll.h>
  29 #include <sys/epoll.h>
  30 #include <sys/wait.h>
  31 #include <sys/signalfd.h>
  32
  33 #include "netlink-util.h"
  34 #include "event-util.h"
  35 #include "formats-util.h"
  36 #include "process-util.h"
  37 #include "signal-util.h"
  38 #include "udev.h"
  39
  40 typedef struct Spawn {
  41         const char *cmd;
  42         pid_t pid;
  43         usec_t timeout_warn;
  44         usec_t timeout;
  45 } Spawn;
  46
  47 struct udev_event *udev_event_new(struct udev_device *dev) {
  48         struct udev *udev = udev_device_get_udev(dev);
  49         struct udev_event *event;
  50
  51         event = new0(struct udev_event, 1);
  52         if (event == NULL)
  53                 return NULL;
  54         event->dev = dev;
  55         event->udev = udev;
  56         udev_list_init(udev, &event->run_list, false);
  57         udev_list_init(udev, &event->seclabel_list, false);
  58         event->birth_usec = clock_boottime_or_monotonic();
  59         return event;
  60 }
  61
  62 void udev_event_unref(struct udev_event *event) {
  63         if (event == NULL)
  64                 return;
  65         sd_netlink_unref(event->rtnl);
  66         udev_list_cleanup(&event->run_list);
  67         udev_list_cleanup(&event->seclabel_list);
  68         free(event->program_result);
  69         free(event->name);
  70         free(event);
  71 }
  72
  73 size_t udev_event_apply_format(struct udev_event *event, const char *src, char *dest, size_t size) {
  74         struct udev_device *dev = event->dev;
  75         enum subst_type {
  76                 SUBST_UNKNOWN,
  77                 SUBST_DEVNODE,
  78                 SUBST_ATTR,
  79                 SUBST_ENV,
  80                 SUBST_KERNEL,
  81                 SUBST_KERNEL_NUMBER,
  82                 SUBST_DRIVER,
  83                 SUBST_DEVPATH,
  84                 SUBST_ID,
  85                 SUBST_MAJOR,
  86                 SUBST_MINOR,
  87                 SUBST_RESULT,
  88                 SUBST_PARENT,
  89                 SUBST_NAME,
  90                 SUBST_LINKS,
  91                 SUBST_ROOT,
  92                 SUBST_SYS,
  93         };
  94         static const struct subst_map {
  95                 const char *name;
  96                 const char fmt;
  97                 enum subst_type type;
  98         } map[] = {
  99                 { .name = "devnode",  .fmt = 'N', .type = SUBST_DEVNODE },
 100                 { .name = "tempnode", .fmt = 'N', .type = SUBST_DEVNODE },
 101                 { .name = "attr",     .fmt = 's', .type = SUBST_ATTR },
 102                 { .name = "sysfs",    .fmt = 's', .type = SUBST_ATTR },
 103                 { .name = "env",      .fmt = 'E', .type = SUBST_ENV },
 104                 { .name = "kernel",   .fmt = 'k', .type = SUBST_KERNEL },
 105                 { .name = "number",   .fmt = 'n', .type = SUBST_KERNEL_NUMBER },
 106                 { .name = "driver",   .fmt = 'd', .type = SUBST_DRIVER },
 107                 { .name = "devpath",  .fmt = 'p', .type = SUBST_DEVPATH },
 108                 { .name = "id",       .fmt = 'b', .type = SUBST_ID },
 109                 { .name = "major",    .fmt = 'M', .type = SUBST_MAJOR },
 110                 { .name = "minor",    .fmt = 'm', .type = SUBST_MINOR },
 111                 { .name = "result",   .fmt = 'c', .type = SUBST_RESULT },
 112                 { .name = "parent",   .fmt = 'P', .type = SUBST_PARENT },
 113                 { .name = "name",     .fmt = 'D', .type = SUBST_NAME },
 114                 { .name = "links",    .fmt = 'L', .type = SUBST_LINKS },
 115                 { .name = "root",     .fmt = 'r', .type = SUBST_ROOT },
 116                 { .name = "sys",      .fmt = 'S', .type = SUBST_SYS },
 117         };
 118         const char *from;
 119         char *s;
 120         size_t l;
 121
 122         assert(dev);
 123
 124         from = src;
 125         s = dest;
 126         l = size;
 127
 128         for (;;) {
 129                 enum subst_type type = SUBST_UNKNOWN;
 130                 char attrbuf[UTIL_PATH_SIZE];
 131                 char *attr = NULL;
 132
 133                 while (from[0] != '\0') {
 134                         if (from[0] == '$') {
 135                                 /* substitute named variable */
 136                                 unsigned int i;
 137
 138                                 if (from[1] == '$') {
 139                                         from++;
 140                                         goto copy;
 141                                 }
 142
 143                                 for (i = 0; i < ELEMENTSOF(map); i++) {
 144                                         if (startswith(&from[1], map[i].name)) {
 145                                                 type = map[i].type;
 146                                                 from += strlen(map[i].name)+1;
 147                                                 goto subst;
 148                                         }
 149                                 }
 150                         } else if (from[0] == '%') {
 151                                 /* substitute format char */
 152                                 unsigned int i;
 153
 154                                 if (from[1] == '%') {
 155                                         from++;
 156                                         goto copy;
 157                                 }
 158
 159                                 for (i = 0; i < ELEMENTSOF(map); i++) {
 160                                         if (from[1] == map[i].fmt) {
 161                                                 type = map[i].type;
 162                                                 from += 2;
 163                                                 goto subst;
 164                                         }
 165                                 }
 166                         }
 167 copy:
 168                         /* copy char */
 169                         if (l == 0)
 170                                 goto out;
 171                         s[0] = from[0];
 172                         from++;
 173                         s++;
 174                         l--;
 175                 }
 176
 177                 goto out;
 178 subst:
 179                 /* extract possible $format{attr} */
 180                 if (from[0] == '{') {
 181                         unsigned int i;
 182
 183                         from++;
 184                         for (i = 0; from[i] != '}'; i++) {
 185                                 if (from[i] == '\0') {
 186                                         log_error("missing closing brace for format '%s'", src);
 187                                         goto out;
 188                                 }
 189                         }
 190                         if (i >= sizeof(attrbuf))
 191                                 goto out;
 192                         memcpy(attrbuf, from, i);
 193                         attrbuf[i] = '\0';
 194                         from += i+1;
 195                         attr = attrbuf;
 196                 } else {
 197                         attr = NULL;
 198                 }
 199
 200                 switch (type) {
 201                 case SUBST_DEVPATH:
 202                         l = strpcpy(&s, l, udev_device_get_devpath(dev));
 203                         break;
 204                 case SUBST_KERNEL:
 205                         l = strpcpy(&s, l, udev_device_get_sysname(dev));
 206                         break;
 207                 case SUBST_KERNEL_NUMBER:
 208                         if (udev_device_get_sysnum(dev) == NULL)
 209                                 break;
 210                         l = strpcpy(&s, l, udev_device_get_sysnum(dev));
 211                         break;
 212                 case SUBST_ID:
 213                         if (event->dev_parent == NULL)
 214                                 break;
 215                         l = strpcpy(&s, l, udev_device_get_sysname(event->dev_parent));
 216                         break;
 217                 case SUBST_DRIVER: {
 218                         const char *driver;
 219
 220                         if (event->dev_parent == NULL)
 221                                 break;
 222
 223                         driver = udev_device_get_driver(event->dev_parent);
 224                         if (driver == NULL)
 225                                 break;
 226                         l = strpcpy(&s, l, driver);
 227                         break;
 228                 }
 229                 case SUBST_MAJOR: {
 230                         char num[UTIL_PATH_SIZE];
 231
 232                         sprintf(num, "%u", major(udev_device_get_devnum(dev)));
 233                         l = strpcpy(&s, l, num);
 234                         break;
 235                 }
 236                 case SUBST_MINOR: {
 237                         char num[UTIL_PATH_SIZE];
 238
 239                         sprintf(num, "%u", minor(udev_device_get_devnum(dev)));
 240                         l = strpcpy(&s, l, num);
 241                         break;
 242                 }
 243                 case SUBST_RESULT: {
 244                         char *rest;
 245                         int i;
 246
 247                         if (event->program_result == NULL)
 248                                 break;
 249                         /* get part part of the result string */
 250                         i = 0;
 251                         if (attr != NULL)
 252                                 i = strtoul(attr, &rest, 10);
 253                         if (i > 0) {
 254                                 char result[UTIL_PATH_SIZE];
 255                                 char tmp[UTIL_PATH_SIZE];
 256                                 char *cpos;
 257
 258                                 strscpy(result, sizeof(result), event->program_result);
 259                                 cpos = result;
 260                                 while (--i) {
 261                                         while (cpos[0] != '\0' && !isspace(cpos[0]))
 262                                                 cpos++;
 263                                         while (isspace(cpos[0]))
 264                                                 cpos++;
 265                                         if (cpos[0] == '\0')
 266                                                 break;
 267                                 }
 268                                 if (i > 0) {
 269                                         log_error("requested part of result string not found");
 270                                         break;
 271                                 }
 272                                 strscpy(tmp, sizeof(tmp), cpos);
 273                                 /* %{2+}c copies the whole string from the second part on */
 274                                 if (rest[0] != '+') {
 275                                         cpos = strchr(tmp, ' ');
 276                                         if (cpos)
 277                                                 cpos[0] = '\0';
 278                                 }
 279                                 l = strpcpy(&s, l, tmp);
 280                         } else {
 281                                 l = strpcpy(&s, l, event->program_result);
 282                         }
 283                         break;
 284                 }
 285                 case SUBST_ATTR: {
 286                         const char *value = NULL;
 287                         char vbuf[UTIL_NAME_SIZE];
 288                         size_t len;
 289                         int count;
 290
 291                         if (attr == NULL) {
 292                                 log_error("missing file parameter for attr");
 293                                 break;
 294                         }
 295
 296                         /* try to read the value specified by "[dmi/id]product_name" */
 297                         if (util_resolve_subsys_kernel(event->udev, attr, vbuf, sizeof(vbuf), 1) == 0)
 298                                 value = vbuf;
 299
 300                         /* try to read the attribute the device */
 301                         if (value == NULL)
 302                                 value = udev_device_get_sysattr_value(event->dev, attr);
 303
 304                         /* try to read the attribute of the parent device, other matches have selected */
 305                         if (value == NULL && event->dev_parent != NULL && event->dev_parent != event->dev)
 306                                 value = udev_device_get_sysattr_value(event->dev_parent, attr);
 307
 308                         if (value == NULL)
 309                                 break;
 310
 311                         /* strip trailing whitespace, and replace unwanted characters */
 312                         if (value != vbuf)
 313                                 strscpy(vbuf, sizeof(vbuf), value);
 314                         len = strlen(vbuf);
 315                         while (len > 0 && isspace(vbuf[--len]))
 316                                 vbuf[len] = '\0';
 317                         count = util_replace_chars(vbuf, UDEV_ALLOWED_CHARS_INPUT);
 318                         if (count > 0)
 319                                 log_debug("%i character(s) replaced" , count);
 320                         l = strpcpy(&s, l, vbuf);
 321                         break;
 322                 }
 323                 case SUBST_PARENT: {
 324                         struct udev_device *dev_parent;
 325                         const char *devnode;
 326
 327                         dev_parent = udev_device_get_parent(event->dev);
 328                         if (dev_parent == NULL)
 329                                 break;
 330                         devnode = udev_device_get_devnode(dev_parent);
 331                         if (devnode != NULL)
 332                                 l = strpcpy(&s, l, devnode + strlen("/dev/"));
 333                         break;
 334                 }
 335                 case SUBST_DEVNODE:
 336                         if (udev_device_get_devnode(dev) != NULL)
 337                                 l = strpcpy(&s, l, udev_device_get_devnode(dev));
 338                         break;
 339                 case SUBST_NAME:
 340                         if (event->name != NULL)
 341                                 l = strpcpy(&s, l, event->name);
 342                         else if (udev_device_get_devnode(dev) != NULL)
 343                                 l = strpcpy(&s, l, udev_device_get_devnode(dev) + strlen("/dev/"));
 344                         else
 345                                 l = strpcpy(&s, l, udev_device_get_sysname(dev));
 346                         break;
 347                 case SUBST_LINKS: {
 348                         struct udev_list_entry *list_entry;
 349
 350                         list_entry = udev_device_get_devlinks_list_entry(dev);
 351                         if (list_entry == NULL)
 352                                 break;
 353                         l = strpcpy(&s, l, udev_list_entry_get_name(list_entry) + strlen("/dev/"));
 354                         udev_list_entry_foreach(list_entry, udev_list_entry_get_next(list_entry))
 355                                 l = strpcpyl(&s, l, " ", udev_list_entry_get_name(list_entry) + strlen("/dev/"), NULL);
 356                         break;
 357                 }
 358                 case SUBST_ROOT:
 359                         l = strpcpy(&s, l, "/dev");
 360                         break;
 361                 case SUBST_SYS:
 362                         l = strpcpy(&s, l, "/sys");
 363                         break;
 364                 case SUBST_ENV:
 365                         if (attr == NULL) {
 366                                 break;
 367                         } else {
 368                                 const char *value;
 369
 370                                 value = udev_device_get_property_value(event->dev, attr);
 371                                 if (value == NULL)
 372                                         break;
 373                                 l = strpcpy(&s, l, value);
 374                                 break;
 375                         }
 376                 default:
 377                         log_error("unknown substitution type=%i", type);
 378                         break;
 379                 }
 380         }
 381
 382 out:
 383         s[0] = '\0';
 384         return l;
 385 }
 386
 387 static int spawn_exec(struct udev_event *event,
 388                       const char *cmd, char *const argv[], char **envp,
 389                       int fd_stdout, int fd_stderr) {
 390         _cleanup_close_ int fd = -1;
 391
 392         /* discard child output or connect to pipe */
 393         fd = open("/dev/null", O_RDWR);
 394         if (fd >= 0) {
 395                 dup2(fd, STDIN_FILENO);
 396                 if (fd_stdout < 0)
 397                         dup2(fd, STDOUT_FILENO);
 398                 if (fd_stderr < 0)
 399                         dup2(fd, STDERR_FILENO);
 400         } else
 401                 log_error_errno(errno, "open /dev/null failed: %m");
 402
 403         /* connect pipes to std{out,err} */
 404         if (fd_stdout >= 0) {
 405                 dup2(fd_stdout, STDOUT_FILENO);
 406                 safe_close(fd_stdout);
 407         }
 408         if (fd_stderr >= 0) {
 409                 dup2(fd_stderr, STDERR_FILENO);
 410                 safe_close(fd_stderr);
 411         }
 412
 413         /* terminate child in case parent goes away */
 414         prctl(PR_SET_PDEATHSIG, SIGTERM);
 415
 416         /* restore sigmask before exec */
 417         (void) reset_signal_mask();
 418
 419         execve(argv[0], argv, envp);
 420
 421         /* exec failed */
 422         log_error_errno(errno, "failed to execute '%s' '%s': %m", argv[0], cmd);
 423
 424         return -errno;
 425 }
 426
 427 static void spawn_read(struct udev_event *event,
 428                        usec_t timeout_usec,
 429                        const char *cmd,
 430                        int fd_stdout, int fd_stderr,
 431                        char *result, size_t ressize) {
 432         _cleanup_close_ int fd_ep = -1;
 433         struct epoll_event ep_outpipe = {
 434                 .events = EPOLLIN,
 435                 .data.ptr = &fd_stdout,
 436         };
 437         struct epoll_event ep_errpipe = {
 438                 .events = EPOLLIN,
 439                 .data.ptr = &fd_stderr,
 440         };
 441         size_t respos = 0;
 442         int r;
 443
 444         /* read from child if requested */
 445         if (fd_stdout < 0 && fd_stderr < 0)
 446                 return;
 447
 448         fd_ep = epoll_create1(EPOLL_CLOEXEC);
 449         if (fd_ep < 0) {
 450                 log_error_errno(errno, "error creating epoll fd: %m");
 451                 return;
 452         }
 453
 454         if (fd_stdout >= 0) {
 455                 r = epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_stdout, &ep_outpipe);
 456                 if (r < 0) {
 457                         log_error_errno(errno, "fail to add stdout fd to epoll: %m");
 458                         return;
 459                 }
 460         }
 461
 462         if (fd_stderr >= 0) {
 463                 r = epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_stderr, &ep_errpipe);
 464                 if (r < 0) {
 465                         log_error_errno(errno, "fail to add stderr fd to epoll: %m");
 466                         return;
 467                 }
 468         }
 469
 470         /* read child output */
 471         while (fd_stdout >= 0 || fd_stderr >= 0) {
 472                 int timeout;
 473                 int fdcount;
 474                 struct epoll_event ev[4];
 475                 int i;
 476
 477                 if (timeout_usec > 0) {
 478                         usec_t age_usec;
 479
 480                         age_usec = clock_boottime_or_monotonic() - event->birth_usec;
 481                         if (age_usec >= timeout_usec) {
 482                                 log_error("timeout '%s'", cmd);
 483                                 return;
 484                         }
 485                         timeout = ((timeout_usec - age_usec) / USEC_PER_MSEC) + MSEC_PER_SEC;
 486                 } else {
 487                         timeout = -1;
 488                 }
 489
 490                 fdcount = epoll_wait(fd_ep, ev, ELEMENTSOF(ev), timeout);
 491                 if (fdcount < 0) {
 492                         if (errno == EINTR)
 493                                 continue;
 494                         log_error_errno(errno, "failed to poll: %m");
 495                         return;
 496                 } else if (fdcount == 0) {
 497                         log_error("timeout '%s'", cmd);
 498                         return;
 499                 }
 500
 501                 for (i = 0; i < fdcount; i++) {
 502                         int *fd = (int *)ev[i].data.ptr;
 503
 504                         if (*fd < 0)
 505                                 continue;
 506
 507                         if (ev[i].events & EPOLLIN) {
 508                                 ssize_t count;
 509                                 char buf[4096];
 510
 511                                 count = read(*fd, buf, sizeof(buf)-1);
 512                                 if (count <= 0)
 513                                         continue;
 514                                 buf[count] = '\0';
 515
 516                                 /* store stdout result */
 517                                 if (result != NULL && *fd == fd_stdout) {
 518                                         if (respos + count < ressize) {
 519                                                 memcpy(&result[respos], buf, count);
 520                                                 respos += count;
 521                                         } else {
 522                                                 log_error("'%s' ressize %zu too short", cmd, ressize);
 523                                         }
 524                                 }
 525
 526                                 /* log debug output only if we watch stderr */
 527                                 if (fd_stderr >= 0) {
 528                                         char *pos;
 529                                         char *line;
 530
 531                                         pos = buf;
 532                                         while ((line = strsep(&pos, "\n"))) {
 533                                                 if (pos != NULL || line[0] != '\0')
 534                                                         log_debug("'%s'(%s) '%s'", cmd, *fd == fd_stdout ? "out" : "err" , line);
 535                                         }
 536                                 }
 537                         } else if (ev[i].events & EPOLLHUP) {
 538                                 r = epoll_ctl(fd_ep, EPOLL_CTL_DEL, *fd, NULL);
 539                                 if (r < 0) {
 540                                         log_error_errno(errno, "failed to remove fd from epoll: %m");
 541                                         return;
 542                                 }
 543                                 *fd = -1;
 544                         }
 545                 }
 546         }
 547
 548         /* return the child's stdout string */
 549         if (result != NULL)
 550                 result[respos] = '\0';
 551 }
 552
 553 static int on_spawn_timeout(sd_event_source *s, uint64_t usec, void *userdata) {
 554         Spawn *spawn = userdata;
 555         char timeout[FORMAT_TIMESTAMP_RELATIVE_MAX];
 556
 557         assert(spawn);
 558
 559         kill_and_sigcont(spawn->pid, SIGKILL);
 560
 561         log_error("spawned process '%s' ["PID_FMT"] timed out after %s, killing", spawn->cmd, spawn->pid,
 562                   format_timestamp_relative(timeout, sizeof(timeout), spawn->timeout));
 563
 564         return 1;
 565 }
 566
 567 static int on_spawn_timeout_warning(sd_event_source *s, uint64_t usec, void *userdata) {
 568         Spawn *spawn = userdata;
 569         char timeout[FORMAT_TIMESTAMP_RELATIVE_MAX];
 570
 571         assert(spawn);
 572
 573         log_warning("spawned process '%s' ["PID_FMT"] is taking longer than %s to complete", spawn->cmd, spawn->pid,
 574                     format_timestamp_relative(timeout, sizeof(timeout), spawn->timeout));
 575
 576         return 1;
 577 }
 578
 579 static int on_spawn_sigchld(sd_event_source *s, const siginfo_t *si, void *userdata) {
 580         Spawn *spawn = userdata;
 581
 582         assert(spawn);
 583
 584         switch (si->si_code) {
 585         case CLD_EXITED:
 586                 if (si->si_status != 0)
 587                         log_warning("process '%s' failed with exit code %i.", spawn->cmd, si->si_status);
 588                 else {
 589                         log_debug("process '%s' succeeded.", spawn->cmd);
 590                         sd_event_exit(sd_event_source_get_event(s), 0);
 591
 592                         return 1;
 593                 }
 594
 595                 break;
 596         case CLD_KILLED:
 597         case CLD_DUMPED:
 598                 log_warning("process '%s' terminated by signal %s.", spawn->cmd, signal_to_string(si->si_status));
 599
 600                 break;
 601         default:
 602                 log_error("process '%s' failed due to unknown reason.", spawn->cmd);
 603         }
 604
 605         sd_event_exit(sd_event_source_get_event(s), -EIO);
 606
 607         return 1;
 608 }
 609
 610 static int spawn_wait(struct udev_event *event,
 611                       usec_t timeout_usec,
 612                       usec_t timeout_warn_usec,
 613                       const char *cmd, pid_t pid) {
 614         Spawn spawn = {
 615                 .cmd = cmd,
 616                 .pid = pid,
 617         };
 618         _cleanup_event_unref_ sd_event *e = NULL;
 619         int r, ret;
 620
 621         r = sd_event_new(&e);
 622         if (r < 0)
 623                 return r;
 624
 625         if (timeout_usec > 0) {
 626                 usec_t usec, age_usec;
 627
 628                 usec = now(clock_boottime_or_monotonic());
 629                 age_usec = usec - event->birth_usec;
 630                 if (age_usec < timeout_usec) {
 631                         if (timeout_warn_usec > 0 && timeout_warn_usec < timeout_usec && age_usec < timeout_warn_usec) {
 632                                 spawn.timeout_warn = timeout_warn_usec - age_usec;
 633
 634                                 r = sd_event_add_time(e, NULL, clock_boottime_or_monotonic(),
 635                                                       usec + spawn.timeout_warn, USEC_PER_SEC,
 636                                                       on_spawn_timeout_warning, &spawn);
 637                                 if (r < 0)
 638                                         return r;
 639                         }
 640
 641                         spawn.timeout = timeout_usec - age_usec;
 642
 643                         r = sd_event_add_time(e, NULL, clock_boottime_or_monotonic(),
 644                                               usec + spawn.timeout, USEC_PER_SEC, on_spawn_timeout, &spawn);
 645                         if (r < 0)
 646                                 return r;
 647                 }
 648         }
 649
 650         r = sd_event_add_child(e, NULL, pid, WEXITED, on_spawn_sigchld, &spawn);
 651         if (r < 0)
 652                 return r;
 653
 654         r = sd_event_loop(e);
 655         if (r < 0)
 656                 return r;
 657
 658         r = sd_event_get_exit_code(e, &ret);
 659         if (r < 0)
 660                 return r;
 661
 662         return ret;
 663 }
 664
 665 int udev_build_argv(struct udev *udev, char *cmd, int *argc, char *argv[]) {
 666         int i = 0;
 667         char *pos;
 668
 669         if (strchr(cmd, ' ') == NULL) {
 670                 argv[i++] = cmd;
 671                 goto out;
 672         }
 673
 674         pos = cmd;
 675         while (pos != NULL && pos[0] != '\0') {
 676                 if (pos[0] == '\'') {
 677                         /* do not separate quotes */
 678                         pos++;
 679                         argv[i] = strsep(&pos, "\'");
 680                         if (pos != NULL)
 681                                 while (pos[0] == ' ')
 682                                         pos++;
 683                 } else {
 684                         argv[i] = strsep(&pos, " ");
 685                         if (pos != NULL)
 686                                 while (pos[0] == ' ')
 687                                         pos++;
 688                 }
 689                 i++;
 690         }
 691 out:
 692         argv[i] = NULL;
 693         if (argc)
 694                 *argc = i;
 695         return 0;
 696 }
 697
 698 int udev_event_spawn(struct udev_event *event,
 699                      usec_t timeout_usec,
 700                      usec_t timeout_warn_usec,
 701                      const char *cmd, char **envp,
 702                      char *result, size_t ressize) {
 703         int outpipe[2] = {-1, -1};
 704         int errpipe[2] = {-1, -1};
 705         pid_t pid;
 706         char arg[UTIL_PATH_SIZE];
 707         char *argv[128];
 708         char program[UTIL_PATH_SIZE];
 709         int err = 0;
 710
 711         strscpy(arg, sizeof(arg), cmd);
 712         udev_build_argv(event->udev, arg, NULL, argv);
 713
 714         /* pipes from child to parent */
 715         if (result != NULL || log_get_max_level() >= LOG_INFO) {
 716                 if (pipe2(outpipe, O_NONBLOCK) != 0) {
 717                         err = -errno;
 718                         log_error_errno(errno, "pipe failed: %m");
 719                         goto out;
 720                 }
 721         }
 722         if (log_get_max_level() >= LOG_INFO) {
 723                 if (pipe2(errpipe, O_NONBLOCK) != 0) {
 724                         err = -errno;
 725                         log_error_errno(errno, "pipe failed: %m");
 726                         goto out;
 727                 }
 728         }
 729
 730         /* allow programs in /usr/lib/udev/ to be called without the path */
 731         if (argv[0][0] != '/') {
 732                 strscpyl(program, sizeof(program), UDEVLIBEXECDIR "/", argv[0], NULL);
 733                 argv[0] = program;
 734         }
 735
 736         pid = fork();
 737         switch(pid) {
 738         case 0:
 739                 /* child closes parent's ends of pipes */
 740                 if (outpipe[READ_END] >= 0) {
 741                         close(outpipe[READ_END]);
 742                         outpipe[READ_END] = -1;
 743                 }
 744                 if (errpipe[READ_END] >= 0) {
 745                         close(errpipe[READ_END]);
 746                         errpipe[READ_END] = -1;
 747                 }
 748
 749                 log_debug("starting '%s'", cmd);
 750
 751                 spawn_exec(event, cmd, argv, envp,
 752                            outpipe[WRITE_END], errpipe[WRITE_END]);
 753
 754                 _exit(2 );
 755         case -1:
 756                 log_error_errno(errno, "fork of '%s' failed: %m", cmd);
 757                 err = -1;
 758                 goto out;
 759         default:
 760                 /* parent closed child's ends of pipes */
 761                 if (outpipe[WRITE_END] >= 0) {
 762                         close(outpipe[WRITE_END]);
 763                         outpipe[WRITE_END] = -1;
 764                 }
 765                 if (errpipe[WRITE_END] >= 0) {
 766                         close(errpipe[WRITE_END]);
 767                         errpipe[WRITE_END] = -1;
 768                 }
 769
 770                 spawn_read(event,
 771                            timeout_usec,
 772                            cmd,
 773                            outpipe[READ_END], errpipe[READ_END],
 774                            result, ressize);
 775
 776                 err = spawn_wait(event, timeout_usec, timeout_warn_usec, cmd, pid);
 777         }
 778
 779 out:
 780         if (outpipe[READ_END] >= 0)
 781                 close(outpipe[READ_END]);
 782         if (outpipe[WRITE_END] >= 0)
 783                 close(outpipe[WRITE_END]);
 784         if (errpipe[READ_END] >= 0)
 785                 close(errpipe[READ_END]);
 786         if (errpipe[WRITE_END] >= 0)
 787                 close(errpipe[WRITE_END]);
 788         return err;
 789 }
 790
 791 static int rename_netif(struct udev_event *event) {
 792         struct udev_device *dev = event->dev;
 793         char name[IFNAMSIZ];
 794         const char *oldname;
 795         int r;
 796
 797         oldname = udev_device_get_sysname(dev);
 798
 799         strscpy(name, IFNAMSIZ, event->name);
 800
 801         r = rtnl_set_link_name(&event->rtnl, udev_device_get_ifindex(dev), name);
 802         if (r < 0)
 803                 return log_error_errno(r, "Error changing net interface name '%s' to '%s': %m", oldname, name);
 804
 805         log_debug("renamed network interface '%s' to '%s'", oldname, name);
 806
 807         return 0;
 808 }
 809
 810 void udev_event_execute_rules(struct udev_event *event,
 811                               usec_t timeout_usec, usec_t timeout_warn_usec,
 812                               struct udev_list *properties_list,
 813                               struct udev_rules *rules) {
 814         struct udev_device *dev = event->dev;
 815
 816         if (udev_device_get_subsystem(dev) == NULL)
 817                 return;
 818
 819         if (streq(udev_device_get_action(dev), "remove")) {
 820                 udev_device_read_db(dev);
 821                 udev_device_tag_index(dev, NULL, false);
 822                 udev_device_delete_db(dev);
 823
 824                 if (major(udev_device_get_devnum(dev)) != 0)
 825                         udev_watch_end(event->udev, dev);
 826
 827                 udev_rules_apply_to_event(rules, event,
 828                                           timeout_usec, timeout_warn_usec,
 829                                           properties_list);
 830
 831                 if (major(udev_device_get_devnum(dev)) != 0)
 832                         udev_node_remove(dev);
 833         } else {
 834                 event->dev_db = udev_device_clone_with_db(dev);
 835                 if (event->dev_db != NULL) {
 836                         /* disable watch during event processing */
 837                         if (major(udev_device_get_devnum(dev)) != 0)
 838                                 udev_watch_end(event->udev, event->dev_db);
 839                 }
 840
 841                 if (major(udev_device_get_devnum(dev)) == 0 &&
 842                     streq(udev_device_get_action(dev), "move"))
 843                         udev_device_copy_properties(dev, event->dev_db);
 844
 845                 udev_rules_apply_to_event(rules, event,
 846                                           timeout_usec, timeout_warn_usec,
 847                                           properties_list);
 848
 849                 /* rename a new network interface, if needed */
 850                 if (udev_device_get_ifindex(dev) > 0 && streq(udev_device_get_action(dev), "add") &&
 851                     event->name != NULL && !streq(event->name, udev_device_get_sysname(dev))) {
 852                         int r;
 853
 854                         r = rename_netif(event);
 855                         if (r < 0)
 856                                 log_warning_errno(r, "could not rename interface '%d' from '%s' to '%s': %m", udev_device_get_ifindex(dev),
 857                                                   udev_device_get_sysname(dev), event->name);
 858                         else {
 859                                 r = udev_device_rename(dev, event->name);
 860                                 if (r < 0)
 861                                         log_warning_errno(r, "renamed interface '%d' from '%s' to '%s', but could not update udev_device: %m",
 862                                                           udev_device_get_ifindex(dev), udev_device_get_sysname(dev), event->name);
 863                                 else
 864                                         log_debug("changed devpath to '%s'", udev_device_get_devpath(dev));
 865                         }
 866                 }
 867
 868                 if (major(udev_device_get_devnum(dev)) > 0) {
 869                         bool apply;
 870
 871                         /* remove/update possible left-over symlinks from old database entry */
 872                         if (event->dev_db != NULL)
 873                                 udev_node_update_old_links(dev, event->dev_db);
 874
 875                         if (!event->owner_set)
 876                                 event->uid = udev_device_get_devnode_uid(dev);
 877
 878                         if (!event->group_set)
 879                                 event->gid = udev_device_get_devnode_gid(dev);
 880
 881                         if (!event->mode_set) {
 882                                 if (udev_device_get_devnode_mode(dev) > 0) {
 883                                         /* kernel supplied value */
 884                                         event->mode = udev_device_get_devnode_mode(dev);
 885                                 } else if (event->gid > 0) {
 886                                         /* default 0660 if a group is assigned */
 887                                         event->mode = 0660;
 888                                 } else {
 889                                         /* default 0600 */
 890                                         event->mode = 0600;
 891                                 }
 892                         }
 893
 894                         apply = streq(udev_device_get_action(dev), "add") || event->owner_set || event->group_set || event->mode_set;
 895                         udev_node_add(dev, apply, event->mode, event->uid, event->gid, &event->seclabel_list);
 896                 }
 897
 898                 /* preserve old, or get new initialization timestamp */
 899                 udev_device_ensure_usec_initialized(event->dev, event->dev_db);
 900
 901                 /* (re)write database file */
 902                 udev_device_tag_index(dev, event->dev_db, true);
 903                 udev_device_update_db(dev);
 904                 udev_device_set_is_initialized(dev);
 905
 906                 event->dev_db = udev_device_unref(event->dev_db);
 907         }
 908 }
 909
 910 void udev_event_execute_run(struct udev_event *event, usec_t timeout_usec, usec_t timeout_warn_usec) {
 911         struct udev_list_entry *list_entry;
 912
 913         udev_list_entry_foreach(list_entry, udev_list_get_entry(&event->run_list)) {
 914                 const char *cmd = udev_list_entry_get_name(list_entry);
 915                 enum udev_builtin_cmd builtin_cmd = udev_list_entry_get_num(list_entry);
 916
 917                 if (builtin_cmd < UDEV_BUILTIN_MAX) {
 918                         char command[UTIL_PATH_SIZE];
 919
 920                         udev_event_apply_format(event, cmd, command, sizeof(command));
 921                         udev_builtin_run(event->dev, builtin_cmd, command, false);
 922                 } else {
 923                         char program[UTIL_PATH_SIZE];
 924                         char **envp;
 925
 926                         if (event->exec_delay > 0) {
 927                                 log_debug("delay execution of '%s'", program);
 928                                 sleep(event->exec_delay);
 929                         }
 930
 931                         udev_event_apply_format(event, cmd, program, sizeof(program));
 932                         envp = udev_device_get_properties_envp(event->dev);
 933                         udev_event_spawn(event, timeout_usec, timeout_warn_usec, program, envp, NULL, 0);
 934                 }
 935         }
 936 }