usr.sbin/udevd/udevd_monitor.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 #include <assert.h>
  44
  45 #include <ctype.h>
  46 #include <err.h>
  47 #include <errno.h>
  48 #include <fcntl.h>
  49 #include <libgen.h>
  50 #include <regex.h>
  51 #include <signal.h>
  52 #include <stdarg.h>
  53 #include <stdio.h>
  54 #include <stdlib.h>
  55 #include <string.h>
  56 #include <syslog.h>
  57 #include <unistd.h>
  58 #include <pthread.h>
  59
  60 #include <libprop/proplib.h>
  61 #include <sys/udev.h>
  62 #include "udevd.h"
  63
  64 #define MONITOR_LOCK()          pthread_mutex_lock(&monitor_lock)
  65 #define MONITOR_UNLOCK()        pthread_mutex_unlock(&monitor_lock)
  66
  67 static int _parse_filter_prop(struct udev_monitor *udm, prop_array_t pa);
  68 static int match_filter(struct event_filter *evf, prop_dictionary_t dict);
  69
  70 static int WildCaseCmp(const char *w, const char *s);
  71 static int wildCaseCmp(const char **mary, int d, const char *w, const char *s);
  72
  73 TAILQ_HEAD(udev_monitor_list_head, udev_monitor)        udev_monitor_list;
  74 pthread_mutex_t monitor_lock;
  75
  76
  77 void
  78 monitor_queue_event(prop_dictionary_t ev_dict)
  79 {
  80         struct udev_monitor             *udm;
  81         struct udev_monitor_event       *udm_ev;
  82
  83         MONITOR_LOCK();
  84
  85         TAILQ_FOREACH(udm, &udev_monitor_list, link) {
  86                 udm_ev = malloc(sizeof(struct udev_monitor_event));
  87                 if (udm_ev == NULL)
  88                         continue;
  89
  90                 prop_object_retain(ev_dict);
  91                 udm_ev->ev_dict = ev_dict;
  92
  93                 if (match_event_filter(udm,
  94                     prop_dictionary_get(udm_ev->ev_dict, "evdict")) == 0) {
  95                         prop_object_release(ev_dict);
  96                         free(udm_ev);
  97                         continue;
  98                 }
  99
 100                 pthread_mutex_lock(&udm->q_lock);
 101                 TAILQ_INSERT_TAIL(&udm->ev_queue, udm_ev, link);
 102                 pthread_cond_signal(&udm->cond);
 103                 pthread_mutex_unlock(&udm->q_lock);
 104         }
 105
 106         MONITOR_UNLOCK();
 107 }
 108
 109 struct udev_monitor *
 110 udev_monitor_init(struct client_info *cli, prop_array_t filters)
 111 {
 112         struct udev_monitor *udm;
 113         int error;
 114
 115         udm = malloc(sizeof(struct udev_monitor));
 116         if (udm == NULL)
 117                 return NULL;
 118
 119         TAILQ_INIT(&udm->ev_queue);
 120         TAILQ_INIT(&udm->ev_filt);
 121
 122         pthread_mutex_init(&udm->q_lock, NULL);
 123         pthread_cond_init(&udm->cond, NULL);
 124         udm->cli = cli;
 125
 126         if (filters != NULL) {
 127                 error = _parse_filter_prop(udm, filters);
 128                 /* XXX: ignore error for now */
 129         }
 130
 131         return udm;
 132 }
 133
 134 void
 135 udev_monitor_free(struct udev_monitor *udm)
 136 {
 137         struct event_filter     *evf;
 138         struct udev_monitor_event       *udm_ev;
 139
 140         pthread_mutex_lock(&udm->q_lock);
 141
 142         while ((udm_ev = TAILQ_FIRST(&udm->ev_queue)) != NULL) {
 143                 prop_object_release(udm_ev->ev_dict);
 144                 udm_ev->ev_dict = NULL;
 145                 TAILQ_REMOVE(&udm->ev_queue, udm_ev, link);
 146                 free(udm_ev);
 147         }
 148
 149         while ((evf = TAILQ_FIRST(&udm->ev_filt)) != NULL) {
 150                 TAILQ_REMOVE(&udm->ev_filt, evf, link);
 151                 free(evf);
 152         }
 153
 154         pthread_mutex_unlock(&udm->q_lock);
 155         free(udm);
 156 }
 157
 158 int
 159 client_cmd_monitor(struct client_info *cli, prop_dictionary_t dict)
 160 {
 161         prop_array_t    pa;
 162         prop_object_t   po;
 163         struct udev_monitor     *udm;
 164         struct udev_monitor_event       *udm_ev;
 165         char *xml;
 166         ssize_t r;
 167         int ok = 1;
 168
 169         pa = NULL;
 170         po = prop_dictionary_get(dict, "filters");
 171         if ((po != NULL) && prop_object_type(po) == PROP_TYPE_ARRAY) {
 172                 pa = po;
 173         }
 174
 175         udm = udev_monitor_init(cli, pa);
 176         if (udm == NULL)
 177                 return 1;
 178
 179         MONITOR_LOCK();
 180         TAILQ_INSERT_TAIL(&udev_monitor_list, udm, link);
 181         MONITOR_UNLOCK();
 182
 183         pthread_mutex_lock(&udm->q_lock);
 184         while (ok) {
 185                 pthread_cond_wait(&udm->cond, &udm->q_lock);
 186
 187                 udm_ev = TAILQ_FIRST(&udm->ev_queue);
 188                 if (udm_ev == NULL)
 189                         continue;
 190
 191                 assert(udm_ev->ev_dict != NULL);
 192                 xml = prop_dictionary_externalize(udm_ev->ev_dict);
 193                 if (xml == NULL)
 194                         continue;
 195
 196                 prop_object_release(udm_ev->ev_dict);
 197                 udm_ev->ev_dict = NULL;
 198                 TAILQ_REMOVE(&udm->ev_queue, udm_ev, link);
 199                 free(udm_ev);
 200
 201                 r = send_xml(cli->fd, xml);
 202                 if (r <= 0)
 203                         goto end;
 204
 205                 free(xml);
 206                 continue;
 207 end:
 208                 pthread_mutex_unlock(&udm->q_lock);
 209                 close(cli->fd);
 210                 ok = 0;
 211                 free(xml);
 212         }
 213
 214         MONITOR_LOCK();
 215         TAILQ_REMOVE(&udev_monitor_list, udm, link);
 216         MONITOR_UNLOCK();
 217
 218         udev_monitor_free(udm);
 219
 220         return 1;
 221 }
 222
 223 static int
 224 _parse_filter_prop(struct udev_monitor *udm, prop_array_t pa)
 225 {
 226         prop_string_t   ps;
 227         prop_number_t   pn;
 228         prop_object_iterator_t  iter;
 229         prop_dictionary_t       dict;
 230         struct event_filter *evf;
 231         int error;
 232
 233         iter = prop_array_iterator(pa);
 234         if (iter == NULL)
 235                 return -1;
 236
 237         while ((dict = prop_object_iterator_next(iter)) != NULL) {
 238                 evf = malloc(sizeof(struct event_filter));
 239                 if (evf == NULL)
 240                         goto error_alloc;
 241
 242                 ps = prop_dictionary_get(dict, "key");
 243                 if (ps == NULL)
 244                         goto error_out;
 245                 evf->key = prop_string_cstring(ps);
 246                 if (evf->key == NULL)
 247                         goto error_out;
 248
 249                 pn = prop_dictionary_get(dict, "type");
 250                 if (pn == NULL)
 251                         goto error_out_ps;
 252
 253                 ps = prop_dictionary_get(dict, "expr");
 254                 if (ps == NULL)
 255                         goto error_out_ps;
 256
 257                 if (prop_dictionary_get(dict, "negative"))
 258                         evf->neg = 1;
 259                 else
 260                         evf->neg = 0;
 261
 262                 evf->type = prop_number_integer_value(pn);
 263                 switch (evf->type) {
 264                 case EVENT_FILTER_TYPE_WILDCARD:
 265                         evf->wildcard_match = prop_string_cstring(ps);
 266                         if (evf->wildcard_match == NULL)
 267                                 goto error_out_ps;
 268                         break;
 269
 270                 case EVENT_FILTER_TYPE_REGEX:
 271                         error = regcomp(&evf->regex_match, prop_string_cstring_nocopy(ps), REG_ICASE | REG_NOSUB);
 272                         if (error)
 273                                 goto error_out_ps;
 274                         break;
 275
 276                 default:
 277                         goto error_out_ps;
 278                 }
 279
 280                 pthread_mutex_lock(&udm->q_lock);
 281                 TAILQ_INSERT_TAIL(&udm->ev_filt, evf, link);
 282                 pthread_mutex_unlock(&udm->q_lock);
 283
 284         }
 285
 286         prop_object_iterator_release(iter);
 287         return 0;
 288
 289 error_out_ps:
 290         free(evf->key);
 291 error_out:
 292         free(evf);
 293 error_alloc:
 294         prop_object_iterator_release(iter);
 295         return -1;
 296 }
 297
 298 /*
 299 Event filter format:
 300 <array>
 301 <dictionary>
 302 <key>key</key>
 303 <value>(e.g. kptr, devnum, ...)</value>
 304 <key>type</key>
 305 <value>(e.g. wildcard or regex)</value>
 306 <key>expr</key>
 307 <value>(regex)</value>
 308 </dictionary>
 309 ... repeat ...
 310 </array>
 311 */
 312
 313 static int
 314 match_filter(struct event_filter *evf, prop_dictionary_t ev_dict)
 315 {
 316         prop_object_t           po;
 317         prop_string_t           ps;
 318         prop_number_t           pn;
 319         char *str;
 320         char buf[128];
 321         int ret;
 322
 323         if (ev_dict == NULL)
 324                 return 0;
 325
 326         prop_object_retain(ev_dict);
 327
 328         assert(prop_dictionary_externalize(ev_dict) != NULL);
 329         if ((po = prop_dictionary_get(ev_dict, evf->key)) == NULL)
 330                 goto no_match;
 331
 332         if (prop_object_type(po) == PROP_TYPE_STRING) {
 333                 ps = po;
 334                 str = __DECONST(char *, prop_string_cstring_nocopy(ps));
 335         } else if (prop_object_type(po) == PROP_TYPE_NUMBER) {
 336                 pn = po;
 337                 if (prop_number_unsigned(pn)) {
 338                         snprintf(buf, sizeof(buf), "%" PRIu64, prop_number_unsigned_integer_value(pn));
 339                 } else {
 340                         snprintf(buf, sizeof(buf), "%" PRIi64, prop_number_integer_value(pn));
 341                 }
 342                 str = buf;
 343         } else {
 344                 syslog(LOG_DEBUG, "Unexpected type in match_filter: %d\n", prop_object_type(po));
 345                 /* Unexpected type */
 346                 goto no_match;
 347         }
 348
 349         switch (evf->type) {
 350         case EVENT_FILTER_TYPE_WILDCARD:
 351                 ret = WildCaseCmp(evf->wildcard_match, str);
 352
 353                 if (ret != 0)
 354                         goto no_match;
 355
 356                 break;
 357         case EVENT_FILTER_TYPE_REGEX:
 358                 ret = regexec(&evf->regex_match, str, 0, NULL, 0);
 359
 360                 if (ret != 0)
 361                         goto no_match;
 362                 break;
 363         default:
 364                 goto no_match;
 365         }
 366
 367         prop_object_release(ev_dict);
 368         return 1;
 369
 370 no_match:
 371         prop_object_release(ev_dict);
 372         return 0;
 373 }
 374
 375 int
 376 match_event_filter(struct udev_monitor *udm, prop_dictionary_t ev_dict)
 377 {
 378         struct event_filter *evf;
 379         int all_negative = 1;
 380
 381         pthread_mutex_lock(&udm->q_lock);
 382
 383         if (TAILQ_EMPTY(&udm->ev_filt))
 384                 return 1;
 385
 386         TAILQ_FOREACH(evf, &udm->ev_filt, link) {
 387                 //printf("match_event_filter 3\n");
 388                 if (evf->neg == 0)
 389                         all_negative = 0;
 390
 391                 if (match_filter(evf, ev_dict)) {
 392                         pthread_mutex_unlock(&udm->q_lock);
 393                         return (1 ^ evf->neg); /* return 1; or 0 for 'nomatch' hit */
 394                 }
 395                 //printf("match_event_filter 5\n");
 396         }
 397
 398         pthread_mutex_unlock(&udm->q_lock);
 399         return (all_negative == 1)?1:0;
 400 }
 401
 402 static int
 403 WildCaseCmp(const char *w, const char *s)
 404 {
 405     int i;
 406     int c;
 407     int slen = strlen(s);
 408     const char **mary;
 409
 410     for (i = c = 0; w[i]; ++i) {
 411         if (w[i] == '*')
 412             ++c;
 413     }
 414     mary = malloc(sizeof(char *) * (c + 1));
 415     if (mary == NULL)
 416              return -1;
 417
 418     for (i = 0; i < c; ++i)
 419         mary[i] = s + slen;
 420     i = wildCaseCmp(mary, 0, w, s);
 421     free(mary);
 422     return(i);
 423 }
 424
 425 /*
 426  * WildCaseCmp() - compare wild string to sane string, case insensitive
 427  *
 428  *      Returns 0 on success, -1 on failure.
 429  */
 430 static int
 431 wildCaseCmp(const char **mary, int d, const char *w, const char *s)
 432 {
 433     int i;
 434
 435     /*
 436      * skip fixed portion
 437      */
 438     for (;;) {
 439         switch(*w) {
 440         case '*':
 441             /*
 442              * optimize terminator
 443              */
 444             if (w[1] == 0)
 445                 return(0);
 446             if (w[1] != '?' && w[1] != '*') {
 447                 /*
 448                  * optimize * followed by non-wild
 449                  */
 450                 for (i = 0; s + i < mary[d]; ++i) {
 451                     if (s[i] == w[1] && wildCaseCmp(mary, d + 1, w + 1, s + i) == 0)
 452                         return(0);
 453                 }
 454             } else {
 455                 /*
 456                  * less-optimal
 457                  */
 458                 for (i = 0; s + i < mary[d]; ++i) {
 459                     if (wildCaseCmp(mary, d + 1, w + 1, s + i) == 0)
 460                         return(0);
 461                 }
 462             }
 463             mary[d] = s;
 464             return(-1);
 465         case '?':
 466             if (*s == 0)
 467                 return(-1);
 468             ++w;
 469             ++s;
 470             break;
 471         default:
 472             if (*w != *s) {
 473                 if (tolower(*w) != tolower(*s))
 474                     return(-1);
 475             }
 476             if (*w == 0)        /* terminator */
 477                 return(0);
 478             ++w;
 479             ++s;
 480             break;
 481         }
 482     }
 483     /* not reached */
 484     return(-1);
 485 }