channels/chan_local.c

   1 /*
   2  * Asterisk -- A telephony toolkit for Linux.
   3  *
   4  * Local Proxy Channel
   5  *
   6  * Copyright (C) 1999, Mark Spencer
   7  *
   8  * Mark Spencer <markster@linux-support.net>
   9  *
  10  * This program is free software, distributed under the terms of
  11  * the GNU General Public License
  12  */
  13
  14 #include <stdio.h>
  15 #include <pthread.h>
  16 #include <string.h>
  17 #include <asterisk/lock.h>
  18 #include <asterisk/channel.h>
  19 #include <asterisk/channel_pvt.h>
  20 #include <asterisk/config.h>
  21 #include <asterisk/logger.h>
  22 #include <asterisk/module.h>
  23 #include <asterisk/pbx.h>
  24 #include <asterisk/options.h>
  25 #include <asterisk/lock.h>
  26 #include <asterisk/sched.h>
  27 #include <asterisk/io.h>
  28 #include <asterisk/rtp.h>
  29 #include <asterisk/acl.h>
  30 #include <asterisk/callerid.h>
  31 #include <asterisk/file.h>
  32 #include <asterisk/cli.h>
  33 #include <asterisk/app.h>
  34 #include <asterisk/musiconhold.h>
  35 #include <asterisk/manager.h>
  36 #include <sys/socket.h>
  37 #include <errno.h>
  38 #include <unistd.h>
  39 #include <stdlib.h>
  40 #include <fcntl.h>
  41 #include <netdb.h>
  42 #include <arpa/inet.h>
  43 #include <sys/signal.h>
  44
  45 static char *desc = "Local Proxy Channel";
  46 static char *type = "Local";
  47 static char *tdesc = "Local Proxy Channel Driver";
  48
  49 static int capability = -1;
  50
  51 static int usecnt =0;
  52 static pthread_mutex_t usecnt_lock = AST_MUTEX_INITIALIZER;
  53
  54 #define IS_OUTBOUND(a,b) (a == b->chan ? 1 : 0)
  55
  56 /* Protect the interface list (of sip_pvt's) */
  57 static pthread_mutex_t locallock = AST_MUTEX_INITIALIZER;
  58
  59 static struct local_pvt {
  60         pthread_mutex_t lock;                           /* Channel private lock */
  61         char context[AST_MAX_EXTENSION];        /* Context to call */
  62         char exten[AST_MAX_EXTENSION];          /* Extension to call */
  63         int reqformat;                                          /* Requested format */
  64         int alreadymasqed;                                      /* Already masqueraded */
  65         struct ast_channel *owner;                      /* Master Channel */
  66         struct ast_channel *chan;                       /* Outbound channel */
  67         struct local_pvt *next;                         /* Next entity */
  68 } *locals = NULL;
  69
  70 static int local_queue_frame(struct local_pvt *p, int isoutbound, struct ast_frame *f)
  71 {
  72         struct ast_channel *other;
  73         if (isoutbound)
  74                 other = p->owner;
  75         else
  76                 other = p->chan;
  77         if (!other)
  78                 return 0;
  79 retrylock:
  80         if (pthread_mutex_trylock(&other->lock)) {
  81                 /* Failed to lock.  Release main lock and try again */
  82                 ast_pthread_mutex_unlock(&p->lock);
  83                 /* Wait just a bit */
  84                 usleep(1);
  85                 ast_pthread_mutex_lock(&p->lock);
  86                 goto retrylock;
  87         }
  88         ast_queue_frame(other, f, 0);
  89         ast_pthread_mutex_unlock(&other->lock);
  90         return 0;
  91 }
  92
  93 static int local_answer(struct ast_channel *ast)
  94 {
  95         struct local_pvt *p = ast->pvt->pvt;
  96         int isoutbound = IS_OUTBOUND(ast, p);
  97         int res = -1;
  98         ast_pthread_mutex_lock(&p->lock);
  99         if (isoutbound) {
 100                 /* Pass along answer since somebody answered us */
 101                 struct ast_frame answer = { AST_FRAME_CONTROL, AST_CONTROL_ANSWER };
 102                 res = local_queue_frame(p, isoutbound, &answer);
 103         } else
 104                 ast_log(LOG_WARNING, "Huh?  Local is being asked to answer?\n");
 105         ast_pthread_mutex_unlock(&p->lock);
 106         return res;
 107 }
 108
 109 static void check_bridge(struct local_pvt *p, int isoutbound)
 110 {
 111         if (p->alreadymasqed)
 112                 return;
 113         if (isoutbound && p->chan && p->chan->bridge && p->owner) {
 114                 /* Masquerade bridged channel into owner */
 115                 ast_channel_masquerade(p->owner, p->chan->bridge);
 116                 p->alreadymasqed = 1;
 117         } else if (!isoutbound && p->owner && p->owner->bridge && p->chan) {
 118                 /* Masquerade bridged channel into chan */
 119                 ast_channel_masquerade(p->chan, p->owner->bridge);
 120                 p->alreadymasqed = 1;
 121         }
 122 }
 123
 124 static struct ast_frame  *local_read(struct ast_channel *ast)
 125 {
 126         static struct ast_frame null = { AST_FRAME_NULL, };
 127         return &null;
 128 }
 129
 130 static int local_write(struct ast_channel *ast, struct ast_frame *f)
 131 {
 132         struct local_pvt *p = ast->pvt->pvt;
 133         int res = -1;
 134         int isoutbound = IS_OUTBOUND(ast, p);
 135
 136
 137         /* Just queue for delivery to the other side */
 138         ast_pthread_mutex_lock(&p->lock);
 139         res = local_queue_frame(p, isoutbound, f);
 140         check_bridge(p, isoutbound);
 141         ast_pthread_mutex_unlock(&p->lock);
 142         return res;
 143 }
 144
 145 static int local_fixup(struct ast_channel *oldchan, struct ast_channel *newchan)
 146 {
 147         struct local_pvt *p = newchan->pvt->pvt;
 148         ast_pthread_mutex_lock(&p->lock);
 149         if ((p->owner != oldchan) && (p->chan != oldchan)) {
 150                 ast_log(LOG_WARNING, "old channel wasn't %p but was %p/%p\n", oldchan, p->owner, p->chan);
 151                 ast_pthread_mutex_unlock(&p->lock);
 152                 return -1;
 153         }
 154         if (p->owner == oldchan)
 155                 p->owner = newchan;
 156         else
 157                 p->chan = newchan;
 158         ast_pthread_mutex_unlock(&p->lock);
 159         return 0;
 160 }
 161
 162 static int local_indicate(struct ast_channel *ast, int condition)
 163 {
 164         struct local_pvt *p = ast->pvt->pvt;
 165         int res = -1;
 166         struct ast_frame f = { AST_FRAME_CONTROL, };
 167         int isoutbound = IS_OUTBOUND(ast, p);
 168         /* Queue up a frame representing the indication as a control frame */
 169         ast_pthread_mutex_lock(&p->lock);
 170         f.subclass = condition;
 171         res = local_queue_frame(p, isoutbound, &f);
 172         ast_pthread_mutex_unlock(&p->lock);
 173         return res;
 174 }
 175
 176 static int local_digit(struct ast_channel *ast, char digit)
 177 {
 178         struct local_pvt *p = ast->pvt->pvt;
 179         int res = -1;
 180         struct ast_frame f = { AST_FRAME_DTMF, };
 181         int isoutbound = IS_OUTBOUND(ast, p);
 182         ast_pthread_mutex_lock(&p->lock);
 183         f.subclass = digit;
 184         res = local_queue_frame(p, isoutbound, &f);
 185         ast_pthread_mutex_unlock(&p->lock);
 186         return res;
 187 }
 188
 189 static int local_call(struct ast_channel *ast, char *dest, int timeout)
 190 {
 191         struct local_pvt *p = ast->pvt->pvt;
 192
 193         if (p->owner->callerid)
 194                 p->chan->callerid = strdup(p->owner->callerid);
 195         else
 196                 p->chan->callerid = NULL;
 197         if (p->owner->ani)
 198                 p->chan->ani = strdup(p->owner->ani);
 199         else
 200                 p->chan->ani = NULL;
 201         /* Start switch on sub channel */
 202         return ast_pbx_start(p->chan);
 203 }
 204
 205 static void local_destroy(struct local_pvt *p)
 206 {
 207         struct local_pvt *cur, *prev = NULL;
 208         ast_pthread_mutex_lock(&locallock);
 209         cur = locals;
 210         while(cur) {
 211                 if (cur == p) {
 212                         if (prev)
 213                                 prev->next = cur->next;
 214                         else
 215                                 locals = cur->next;
 216                         free(cur);
 217                         break;
 218                 }
 219                 prev = cur;
 220                 cur = cur->next;
 221         }
 222         ast_pthread_mutex_unlock(&locallock);
 223         if (!cur)
 224                 ast_log(LOG_WARNING, "Unable ot find local '%s@%s' in local list\n", p->exten, p->context);
 225 }
 226
 227 static int local_hangup(struct ast_channel *ast)
 228 {
 229         struct local_pvt *p = ast->pvt->pvt;
 230         int isoutbound = IS_OUTBOUND(ast, p);
 231         struct ast_frame f = { AST_FRAME_CONTROL, AST_CONTROL_HANGUP };
 232         struct local_pvt *cur, *prev=NULL;
 233         ast_pthread_mutex_lock(&p->lock);
 234         if (isoutbound)
 235                 p->chan = NULL;
 236         else
 237                 p->owner = NULL;
 238         ast->pvt->pvt = NULL;
 239         if (!p->owner && !p->chan) {
 240                 /* Okay, done with the private part now, too. */
 241                 ast_pthread_mutex_unlock(&p->lock);
 242                 /* Remove from list */
 243                 ast_pthread_mutex_lock(&locallock);
 244                 cur = locals;
 245                 while(cur) {
 246                         if (cur == p) {
 247                                 if (prev)
 248                                         prev->next = cur->next;
 249                                 else
 250                                         locals = cur->next;
 251                                 break;
 252                         }
 253                         prev = cur;
 254                         cur = cur->next;
 255                 }
 256                 ast_pthread_mutex_unlock(&locallock);
 257                 /* And destroy */
 258                 free(p);
 259                 return 0;
 260         }
 261         local_queue_frame(p, isoutbound, &f);
 262         ast_pthread_mutex_unlock(&p->lock);
 263         return 0;
 264 }
 265
 266 static struct local_pvt *local_alloc(char *data, int format)
 267 {
 268         struct local_pvt *tmp;
 269         char *c;
 270         tmp = malloc(sizeof(struct local_pvt));
 271         if (tmp) {
 272                 memset(tmp, 0, sizeof(struct local_pvt));
 273                 ast_pthread_mutex_init(&tmp->lock);
 274                 strncpy(tmp->exten, data, sizeof(tmp->exten) - 1);
 275                 c = strchr(tmp->exten, '@');
 276                 if (c) {
 277                         *c = '\0';
 278                         c++;
 279                         strncpy(tmp->context, c, sizeof(tmp->context) - 1);
 280                 } else
 281                         strncpy(tmp->context, "default", sizeof(tmp->context) - 1);
 282                 tmp->reqformat = format;
 283                 if (!ast_exists_extension(NULL, tmp->context, tmp->exten, 1, NULL)) {
 284                         ast_log(LOG_NOTICE, "No such extension/context %s@%s creating local channel\n", tmp->context, tmp->exten);
 285                         free(tmp);
 286                         tmp = NULL;
 287                 } else {
 288                         /* Add to list */
 289                         ast_pthread_mutex_lock(&locallock);
 290                         tmp->next = locals;
 291                         locals = tmp;
 292                         ast_pthread_mutex_unlock(&locallock);
 293                 }
 294
 295         }
 296         return tmp;
 297 }
 298
 299 static struct ast_channel *local_new(struct local_pvt *p, int state)
 300 {
 301         struct ast_channel *tmp, *tmp2;
 302         tmp = ast_channel_alloc(1);
 303         tmp2 = ast_channel_alloc(1);
 304         if (!tmp || !tmp2) {
 305                 if (tmp)
 306                         ast_channel_free(tmp);
 307                 if (tmp2)
 308                         ast_channel_free(tmp2);
 309                 tmp = NULL;
 310         }
 311         if (tmp) {
 312                 tmp->nativeformats = p->reqformat;
 313                 tmp2->nativeformats = p->reqformat;
 314                 snprintf(tmp->name, sizeof(tmp->name), "Local/%s@%s-1", p->exten, p->context);
 315                 snprintf(tmp2->name, sizeof(tmp2->name), "Local/%s@%s-2", p->exten, p->context);
 316                 tmp->type = type;
 317                 tmp2->type = type;
 318                 ast_setstate(tmp, state);
 319                 ast_setstate(tmp2, AST_STATE_RING);
 320                 tmp->writeformat = p->reqformat;;
 321                 tmp2->writeformat = p->reqformat;
 322                 tmp->pvt->rawwriteformat = p->reqformat;
 323                 tmp2->pvt->rawwriteformat = p->reqformat;
 324                 tmp->readformat = p->reqformat;
 325                 tmp2->readformat = p->reqformat;
 326                 tmp->pvt->rawreadformat = p->reqformat;
 327                 tmp2->pvt->rawreadformat = p->reqformat;
 328                 tmp->pvt->pvt = p;
 329                 tmp2->pvt->pvt = p;
 330                 tmp->pvt->send_digit = local_digit;
 331                 tmp2->pvt->send_digit = local_digit;
 332                 tmp->pvt->call = local_call;
 333                 tmp2->pvt->call = local_call;
 334                 tmp->pvt->hangup = local_hangup;
 335                 tmp2->pvt->hangup = local_hangup;
 336                 tmp->pvt->answer = local_answer;
 337                 tmp2->pvt->answer = local_answer;
 338                 tmp->pvt->read = local_read;
 339                 tmp2->pvt->read = local_read;
 340                 tmp->pvt->write = local_write;
 341                 tmp2->pvt->write = local_write;
 342                 tmp->pvt->exception = local_read;
 343                 tmp2->pvt->exception = local_read;
 344                 tmp->pvt->indicate = local_indicate;
 345                 tmp2->pvt->indicate = local_indicate;
 346                 tmp->pvt->fixup = local_fixup;
 347                 tmp2->pvt->fixup = local_fixup;
 348                 p->owner = tmp;
 349                 p->chan = tmp2;
 350                 ast_pthread_mutex_lock(&usecnt_lock);
 351                 usecnt++;
 352                 ast_pthread_mutex_unlock(&usecnt_lock);
 353                 ast_update_use_count();
 354                 strncpy(tmp->context, p->context, sizeof(tmp->context)-1);
 355                 strncpy(tmp2->context, p->context, sizeof(tmp2->context)-1);
 356                 strncpy(tmp2->exten, p->exten, sizeof(tmp->exten)-1);
 357                 tmp->priority = 1;
 358                 tmp2->priority = 1;
 359         } else
 360                 ast_log(LOG_WARNING, "Unable to allocate channel structure\n");
 361         return tmp;
 362 }
 363
 364
 365 static struct ast_channel *local_request(char *type, int format, void *data)
 366 {
 367         struct local_pvt *p;
 368         struct ast_channel *chan = NULL;
 369         p = local_alloc(data, format);
 370         if (p)
 371                 chan = local_new(p, AST_STATE_DOWN);
 372         return chan;
 373 }
 374
 375 static int locals_show(int fd, int argc, char **argv)
 376 {
 377         struct local_pvt *p;
 378
 379         if (argc != 2)
 380                 return RESULT_SHOWUSAGE;
 381         ast_pthread_mutex_lock(&locallock);
 382         p = locals;
 383         while(p) {
 384                 ast_pthread_mutex_lock(&p->lock);
 385                 ast_cli(fd, "%s -- %s@%s\n", p->owner ? p->owner->name : "<unowned>", p->exten, p->context);
 386                 ast_pthread_mutex_unlock(&p->lock);
 387                 p = p->next;
 388         }
 389         if (!locals)
 390                 ast_cli(fd, "No local channels in use\n");
 391         ast_pthread_mutex_unlock(&locallock);
 392         return RESULT_SUCCESS;
 393 }
 394
 395 static char show_locals_usage[] =
 396 "Usage: show locals\n"
 397 "       Provides summary information on locals.\n";
 398
 399 static struct ast_cli_entry cli_show_locals = {
 400         { "show", "locals", NULL }, locals_show,
 401         "Show status of local channels", show_locals_usage, NULL };
 402
 403 int load_module()
 404 {
 405         /* Make sure we can register our sip channel type */
 406         if (ast_channel_register(type, tdesc, capability, local_request)) {
 407                 ast_log(LOG_ERROR, "Unable to register channel class %s\n", type);
 408                 return -1;
 409         }
 410         ast_cli_register(&cli_show_locals);
 411         return 0;
 412 }
 413
 414 int reload()
 415 {
 416         return 0;
 417 }
 418
 419 int unload_module()
 420 {
 421         struct local_pvt *p;
 422         /* First, take us out of the channel loop */
 423         ast_cli_unregister(&cli_show_locals);
 424         ast_channel_unregister(type);
 425         if (!ast_pthread_mutex_lock(&locallock)) {
 426                 /* Hangup all interfaces if they have an owner */
 427                 p = locals;
 428                 while(p) {
 429                         if (p->owner)
 430                                 ast_softhangup(p->owner, AST_SOFTHANGUP_APPUNLOAD);
 431                         p = p->next;
 432                 }
 433                 locals = NULL;
 434                 ast_pthread_mutex_unlock(&locallock);
 435         } else {
 436                 ast_log(LOG_WARNING, "Unable to lock the monitor\n");
 437                 return -1;
 438         }
 439         return 0;
 440 }
 441
 442 int usecount()
 443 {
 444         int res;
 445         ast_pthread_mutex_lock(&usecnt_lock);
 446         res = usecnt;
 447         ast_pthread_mutex_unlock(&usecnt_lock);
 448         return res;
 449 }
 450
 451 char *key()
 452 {
 453         return ASTERISK_GPL_KEY;
 454 }
 455
 456 char *description()
 457 {
 458         return desc;
 459 }
 460