sbin/udevd/udevd.c

   1 /*
   2  * Copyright (c) 2010 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Alex Hornung <ahornung@gmail.com>
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  *
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  * 3. Neither the name of The DragonFly Project nor the names of its
  18  *    contributors may be used to endorse or promote products derived
  19  *    from this software without specific, prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  */
  34 #include <sys/types.h>
  35 #include <sys/device.h>
  36 #include <sys/wait.h>
  37 #include <sys/socket.h>
  38 #include <sys/ioctl.h>
  39 #include <sys/poll.h>
  40 #include <sys/queue.h>
  41 #include <sys/un.h>
  42 #include <cpu/inttypes.h>
  43
  44 #include <err.h>
  45 #include <errno.h>
  46 #include <fcntl.h>
  47 #include <libgen.h>
  48 #include <regex.h>
  49 #include <signal.h>
  50 #include <stdarg.h>
  51 #include <stdio.h>
  52 #include <stdlib.h>
  53 #include <string.h>
  54 #include <syslog.h>
  55 #include <unistd.h>
  56 #include <pthread.h>
  57
  58 #include <libprop/proplib.h>
  59 #include <sys/udev.h>
  60 #include "udevd.h"
  61
  62 int debugopt = 0;
  63
  64 static int udevfd;
  65
  66 extern pthread_mutex_t  monitor_lock;
  67 extern TAILQ_HEAD(udev_monitor_list_head, udev_monitor) udev_monitor_list;
  68 extern TAILQ_HEAD(pdev_array_list_head, pdev_array_entry)       pdev_array_list;
  69
  70 static void usage(void);
  71
  72 int match_dev_dict(prop_dictionary_t, prop_dictionary_t);
  73 prop_dictionary_t find_dev_dict(int64_t, prop_dictionary_t, int *);
  74
  75 void udev_read_event(int);
  76 prop_array_t udev_getdevs(int);
  77
  78 static
  79 void
  80 usage(void)
  81 {
  82         fprintf(stderr, "usage: udevd [-d]\n");
  83         exit(1);
  84 }
  85
  86 int
  87 match_dev_dict(prop_dictionary_t dict, prop_dictionary_t match_dict)
  88 {
  89         prop_number_t   pn, pn2;
  90         prop_string_t   ps, ps2;
  91
  92         if (dict == NULL)
  93                 return 0;
  94
  95         if ((ps = prop_dictionary_get(dict, "name")) == NULL)
  96                 return 0;
  97         if ((ps2 = prop_dictionary_get(match_dict, "name")) == NULL)
  98                 return 0;
  99         if (!prop_string_equals(ps, ps2))
 100                 return 0;
 101
 102         if ((pn = prop_dictionary_get(dict, "devnum")) == NULL)
 103                 return 0;
 104         if ((pn2 = prop_dictionary_get(match_dict, "devnum")) == NULL)
 105                 return 0;
 106         if (!prop_number_equals(pn, pn2))
 107                 return 0;
 108
 109         if ((pn = prop_dictionary_get(dict, "kptr")) == NULL)
 110                 return 0;
 111         if ((pn2 = prop_dictionary_get(match_dict, "kptr")) == NULL)
 112                 return 0;
 113         if (!prop_number_equals(pn, pn2))
 114                 return 0;
 115
 116         return 1;
 117 }
 118
 119 prop_dictionary_t
 120 find_dev_dict(int64_t generation, prop_dictionary_t match_dict, int *idx)
 121 {
 122         struct pdev_array_entry *pae;
 123         prop_array_t            pa;
 124         prop_object_iterator_t  iter;
 125         prop_dictionary_t       dict;
 126         int i = 0;
 127
 128         if (generation == -1)
 129                 pae = pdev_array_entry_get_last();
 130         else
 131                 pae = pdev_array_entry_get(generation);
 132
 133         if (pae == NULL)
 134                 return NULL;
 135
 136         pa = pae->pdev_array;
 137
 138         iter = prop_array_iterator(pa);
 139         if (iter == NULL) {
 140                 pdev_array_entry_unref(pae);
 141                 return NULL;
 142         }
 143
 144         while ((dict = prop_object_iterator_next(iter)) != NULL) {
 145                 if (match_dev_dict(dict, match_dict))
 146                         break;
 147                 ++i;
 148         }
 149
 150         prop_object_iterator_release(iter);
 151
 152         if (idx != NULL)
 153                 *idx = i;
 154
 155         pdev_array_entry_unref(pae);
 156         return dict;
 157 }
 158
 159 void
 160 udev_read_event(int fd)
 161 {
 162         struct pdev_array_entry *pae;
 163         prop_dictionary_t       dict, evdict, devdict;
 164         prop_number_t           pn;
 165         prop_string_t           ps;
 166         prop_object_t           po;
 167         prop_array_t            pa;
 168         char    *xml;
 169         int     n, idx, evtype;
 170         size_t  sz;
 171
 172         sz = 4096 * 1024;
 173
 174         xml = malloc(sz); /* 4 MB */
 175 again:
 176         if ((n = read(fd, xml, sz)) <= 0) {
 177                 if (errno == ENOMEM) {
 178                         sz <<= 2;
 179                         realloc(xml, sz);
 180                         goto again;
 181                 }
 182                 free(xml);
 183                 return;
 184         }
 185
 186         dict = prop_dictionary_internalize(xml);
 187         free(xml);
 188         if (dict == NULL) {
 189                 syslog(LOG_ERR, "internalization of xml failed");
 190                 return;
 191         }
 192
 193         pn = prop_dictionary_get(dict, "evtype");
 194         if (pn == NULL) {
 195                 syslog(LOG_ERR, "read_event: no key evtype");
 196                 goto out;
 197         }
 198
 199         evtype = prop_number_integer_value(pn);
 200
 201         evdict = prop_dictionary_get(dict, "evdict");
 202         if (evdict == NULL) {
 203                 syslog(LOG_ERR, "read_event: no key evdict");
 204                 goto out;
 205         }
 206
 207         switch (evtype) {
 208         case UDEV_EVENT_ATTACH:
 209                 monitor_queue_event(dict);
 210                 pae = pdev_array_entry_get_last();
 211                 pa = prop_array_copy(pae->pdev_array);
 212                 pdev_array_entry_unref(pae);
 213                 if (pa == NULL)
 214                         goto out;
 215                 prop_array_add(pa, evdict);
 216                 pdev_array_entry_insert(pa);
 217                 break;
 218
 219         case UDEV_EVENT_DETACH:
 220                 monitor_queue_event(dict);
 221                 if ((devdict = find_dev_dict(-1, evdict, &idx)) == NULL)
 222                         goto out;
 223                 pae = pdev_array_entry_get_last();
 224                 pa = prop_array_copy(pae->pdev_array);
 225                 pdev_array_entry_unref(pae);
 226                 if (pa == NULL)
 227                         goto out;
 228                 prop_array_remove(pa, idx);
 229                 pdev_array_entry_insert(pa);
 230                 break;
 231
 232         case UDEV_EV_KEY_UPDATE:
 233                 if ((devdict = find_dev_dict(-1, evdict, NULL)) == NULL)
 234                         goto out;
 235                 if ((ps = prop_dictionary_get(evdict, "key")) == NULL)
 236                         goto out;
 237                 if ((po = prop_dictionary_get(evdict, "value")) == NULL)
 238                         goto out;
 239                 /* prop_object_retain(po); */ /* not necessary afaik */
 240                 prop_dictionary_set(devdict, prop_string_cstring_nocopy(ps), po);
 241                 break;
 242
 243         case UDEV_EV_KEY_REMOVE:
 244                 if ((devdict = find_dev_dict(-1, evdict, NULL)) == NULL)
 245                         goto out;
 246                 if ((ps = prop_dictionary_get(evdict, "key")) == NULL)
 247                         goto out;
 248                 prop_dictionary_remove(devdict, prop_string_cstring_nocopy(ps));
 249                 break;
 250
 251         default:
 252                 syslog(LOG_ERR, "read_event: unknown evtype %d", evtype);
 253         }
 254
 255 out:
 256         prop_object_release(dict);
 257         return;
 258 }
 259
 260 prop_array_t
 261 udev_getdevs(int devfd)
 262 {
 263         prop_dictionary_t       pd, rpd;
 264         prop_string_t           ps;
 265         prop_array_t            pa;
 266
 267         pd = prop_dictionary_create();
 268         if (pd == NULL) {
 269                 err(1, "prop_dictionary_create()");
 270         }
 271
 272         ps = prop_string_create_cstring("getdevs");
 273         if (ps == NULL) {
 274                 prop_object_release(pd);
 275                 err(1, "prop_string_create_cstring()");
 276         }
 277
 278         if (prop_dictionary_set(pd, "command", ps) == false) {
 279                 prop_object_release(ps);
 280                 prop_object_release(pd);
 281                 err(1, "prop_dictionary_set()");
 282         }
 283
 284         prop_object_release(ps);
 285
 286         /* Send dictionary to kernel space */
 287         if (prop_dictionary_sendrecv_ioctl(pd, devfd, UDEVPROP, &rpd) != 0)
 288                 err(1, "prop_array_recv_ioctl()");
 289
 290         prop_object_release(pd);
 291
 292         pa = prop_dictionary_get(rpd, "array");
 293         if (pa == NULL)
 294                 goto out;
 295         prop_object_retain(pa);
 296
 297 out:
 298         prop_object_release(rpd);
 299         return pa;
 300 }
 301
 302 static void
 303 killed(int sig __unused)
 304 {
 305         syslog(LOG_ERR, "udevd stopped");
 306         unlink("/var/run/udevd.pid");
 307         pdev_array_clean();
 308 }
 309
 310 int
 311 ignore_signal(int signum)
 312 {
 313         struct sigaction act;
 314         int ret;
 315
 316         act.sa_handler = SIG_IGN;
 317         sigemptyset(&act.sa_mask);
 318         act.sa_flags = 0;
 319
 320         ret = sigaction(signum, &act, NULL);
 321         return ret;
 322 }
 323
 324 static int
 325 set_killed_signal(void)
 326 {
 327         struct sigaction act;
 328         int ret;
 329
 330         act.sa_handler = killed;
 331         sigemptyset(&act.sa_mask);
 332         act.sa_flags = 0;
 333
 334         ret = sigaction(SIGTERM, &act, NULL);
 335         return ret;
 336 }
 337
 338 int main(int argc, char *argv[])
 339 {
 340         int error __unused, i, r, s;
 341         struct pollfd fds[NFDS];
 342         FILE *pidf;
 343         int ch = 0;
 344
 345         while ((ch = getopt(argc, argv, "d")) != -1) {
 346                 switch(ch) {
 347                 case 'd':
 348                         debugopt = 1;
 349                         break;
 350                 default:
 351                         usage();
 352                         /* NOT REACHED */
 353                 }
 354         }
 355         argc -= optind;
 356         argv -= optind;
 357
 358         TAILQ_INIT(&pdev_array_list);
 359         TAILQ_INIT(&udev_monitor_list);
 360
 361         r = ignore_signal(SIGPIPE);
 362         if (r != 0)
 363                 err(1, "could not ignore_signal SIGPIPE");
 364
 365         r = pthread_mutex_init(&(monitor_lock), NULL);
 366         if (r != 0)
 367                 err(1, "could not allocate a pthread_mutex");
 368
 369         if ((udevfd = open(UDEV_DEVICE_PATH, O_RDWR | O_NONBLOCK)) == -1)
 370                 err(1, "%s", UDEV_DEVICE_PATH);
 371         unblock_descriptor(udevfd);
 372
 373         s = init_local_server(LISTEN_SOCKET_FILE, SOCK_STREAM, 0);
 374         if (s < 0)
 375                 err(1, "init_local_server");
 376
 377         pidf = fopen("/var/run/udevd.pid", "w");
 378         if (pidf == NULL)
 379                 err(1, "pidfile");
 380
 381         set_killed_signal();
 382
 383         if (debugopt == 0)
 384                 if (daemon(0, 0) == -1)
 385                         err(1, "daemon");
 386
 387         fprintf(pidf, "%ld\n", (long)getpid());
 388         fclose(pidf);
 389
 390         syslog(LOG_ERR, "udevd started");
 391
 392         pdev_array_entry_insert(udev_getdevs(udevfd));
 393
 394         memset(fds, 0 , sizeof(fds));
 395         fds[UDEV_DEVICE_FD_IDX].fd = udevfd;
 396         fds[UDEV_DEVICE_FD_IDX].events = POLLIN;
 397         fds[UDEV_SOCKET_FD_IDX].fd = s;
 398         fds[UDEV_SOCKET_FD_IDX].events = POLLIN | POLLPRI;
 399
 400         for (;;) {
 401                 r = poll(fds, NFDS, -1);
 402                 if (r < 0)
 403                         err(1, "polling...");
 404
 405                 for (i = 0; (i < NFDS) && (r > 0); i++) {
 406                         if (fds[i].revents == 0)
 407                                 continue;
 408
 409                         --r;
 410                         switch (i) {
 411                         case UDEV_DEVICE_FD_IDX:
 412                                 udev_read_event(udevfd);
 413                                 break;
 414                         case UDEV_SOCKET_FD_IDX:
 415                                 handle_new_connection(s);
 416                                 break;
 417                         default:
 418                                 break;
 419                         }
 420                 }
 421         }
 422
 423         return 0;
 424 }