lib/libwebsockets.c

   1 /*
   2  * libwebsockets - small server side websockets and web server implementation
   3  *
   4  * Copyright (C) 2010 Andy Green <andy@warmcat.com>
   5  *
   6  *  This library is free software; you can redistribute it and/or
   7  *  modify it under the terms of the GNU Lesser General Public
   8  *  License as published by the Free Software Foundation:
   9  *  version 2.1 of the License.
  10  *
  11  *  This library is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  *  Lesser General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU Lesser General Public
  17  *  License along with this library; if not, write to the Free Software
  18  *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
  19  *  MA  02110-1301  USA
  20  */
  21
  22 #include "private-libwebsockets.h"
  23
  24 #ifdef WIN32
  25
  26 #else
  27 #include <ifaddrs.h>
  28 #endif
  29
  30 #ifdef LWS_OPENSSL_SUPPORT
  31 int openssl_websocket_private_data_index;
  32 #endif
  33
  34 /*
  35  * In-place str to lower case
  36  */
  37
  38 static void
  39 strtolower(char *s)
  40 {
  41         while (*s) {
  42                 *s = tolower(*s);
  43                 s++;
  44         }
  45 }
  46
  47 /* file descriptor hash management */
  48
  49 struct libwebsocket *
  50 wsi_from_fd(struct libwebsocket_context *context, int fd)
  51 {
  52         int h = LWS_FD_HASH(fd);
  53         int n = 0;
  54
  55         for (n = 0; n < context->fd_hashtable[h].length; n++)
  56                 if (context->fd_hashtable[h].wsi[n]->sock == fd)
  57                         return context->fd_hashtable[h].wsi[n];
  58
  59         return NULL;
  60 }
  61
  62 int
  63 insert_wsi(struct libwebsocket_context *context, struct libwebsocket *wsi)
  64 {
  65         int h = LWS_FD_HASH(wsi->sock);
  66
  67         if (context->fd_hashtable[h].length == MAX_CLIENTS - 1) {
  68                 fprintf(stderr, "hash table overflow\n");
  69                 return 1;
  70         }
  71
  72         context->fd_hashtable[h].wsi[context->fd_hashtable[h].length++] = wsi;
  73
  74         return 0;
  75 }
  76
  77 int
  78 delete_from_fd(struct libwebsocket_context *context, int fd)
  79 {
  80         int h = LWS_FD_HASH(fd);
  81         int n = 0;
  82
  83         for (n = 0; n < context->fd_hashtable[h].length; n++)
  84                 if (context->fd_hashtable[h].wsi[n]->sock == fd) {
  85                         while (n < context->fd_hashtable[h].length) {
  86                                 context->fd_hashtable[h].wsi[n] =
  87                                             context->fd_hashtable[h].wsi[n + 1];
  88                                 n++;
  89                         }
  90                         context->fd_hashtable[h].length--;
  91
  92                         return 0;
  93                 }
  94
  95         fprintf(stderr, "Failed to find fd %d requested for "
  96                                                    "delete in hashtable\n", fd);
  97         return 1;
  98 }
  99
 100 #ifdef LWS_OPENSSL_SUPPORT
 101 static void
 102 libwebsockets_decode_ssl_error(void)
 103 {
 104         char buf[256];
 105         u_long err;
 106
 107         while ((err = ERR_get_error()) != 0) {
 108                 ERR_error_string_n(err, buf, sizeof(buf));
 109                 fprintf(stderr, "*** %s\n", buf);
 110         }
 111 }
 112 #endif
 113
 114
 115 static int
 116 interface_to_sa(const char* ifname, struct sockaddr_in *addr, size_t addrlen)
 117 {
 118         int rc = -1;
 119 #ifdef WIN32
 120         // TODO
 121 #else
 122         struct ifaddrs *ifr;
 123         struct ifaddrs *ifc;
 124         struct sockaddr_in *sin;
 125
 126         getifaddrs(&ifr);
 127         for (ifc = ifr; ifc != NULL; ifc = ifc->ifa_next) {
 128                 if (strcmp(ifc->ifa_name, ifname))
 129                         continue;
 130                 if (ifc->ifa_addr == NULL)
 131                         continue;
 132                 sin = (struct sockaddr_in *)ifc->ifa_addr;
 133                 if (sin->sin_family != AF_INET)
 134                         continue;
 135                 memcpy(addr, sin, addrlen);
 136                 rc = 0;
 137         }
 138
 139         freeifaddrs(ifr);
 140 #endif
 141         return rc;
 142 }
 143
 144 void
 145 libwebsocket_close_and_free_session(struct libwebsocket_context *context,
 146                          struct libwebsocket *wsi, enum lws_close_status reason)
 147 {
 148         int n;
 149         int old_state;
 150         unsigned char buf[LWS_SEND_BUFFER_PRE_PADDING + 2 +
 151                                                   LWS_SEND_BUFFER_POST_PADDING];
 152         int ret;
 153         int m;
 154         struct lws_tokens eff_buf;
 155
 156         if (!wsi)
 157                 return;
 158
 159         old_state = wsi->state;
 160
 161         if (old_state == WSI_STATE_DEAD_SOCKET)
 162                 return;
 163
 164         wsi->close_reason = reason;
 165
 166         /*
 167          * flush any tx pending from extensions, since we may send close packet
 168          * if there are problems with send, just nuke the connection
 169          */
 170
 171         ret = 1;
 172         while (ret == 1) {
 173
 174                 /* default to nobody has more to spill */
 175
 176                 ret = 0;
 177                 eff_buf.token = NULL;
 178                 eff_buf.token_len = 0;
 179
 180                 /* show every extension the new incoming data */
 181
 182                 for (n = 0; n < wsi->count_active_extensions; n++) {
 183                         m = wsi->active_extensions[n]->callback(
 184                                 wsi->protocol->owning_server, wsi,
 185                                         LWS_EXT_CALLBACK_FLUSH_PENDING_TX,
 186                                    wsi->active_extensions_user[n], &eff_buf, 0);
 187                         if (m < 0) {
 188                                 fprintf(stderr, "Extension reports "
 189                                                                "fatal error\n");
 190                                 goto just_kill_connection;
 191                         }
 192                         if (m)
 193                                 /*
 194                                  * at least one extension told us he has more
 195                                  * to spill, so we will go around again after
 196                                  */
 197                                 ret = 1;
 198                 }
 199
 200                 /* assuming they left us something to send, send it */
 201
 202                 if (eff_buf.token_len)
 203                         if (lws_issue_raw(wsi, (unsigned char *)eff_buf.token,
 204                                                              eff_buf.token_len))
 205                                 goto just_kill_connection;
 206         }
 207
 208         /*
 209          * signal we are closing, libsocket_write will
 210          * add any necessary version-specific stuff.  If the write fails,
 211          * no worries we are closing anyway.  If we didn't initiate this
 212          * close, then our state has been changed to
 213          * WSI_STATE_RETURNED_CLOSE_ALREADY and we will skip this.
 214          *
 215          * Likewise if it's a second call to close this connection after we
 216          * sent the close indication to the peer already, we are in state
 217          * WSI_STATE_AWAITING_CLOSE_ACK and will skip doing this a second time.
 218          */
 219
 220         if (old_state == WSI_STATE_ESTABLISHED &&
 221                                           reason != LWS_CLOSE_STATUS_NOSTATUS) {
 222                 n = libwebsocket_write(wsi, &buf[LWS_SEND_BUFFER_PRE_PADDING],
 223                                                             0, LWS_WRITE_CLOSE);
 224                 if (!n) {
 225                         /*
 226                          * we have sent a nice protocol level indication we
 227                          * now wish to close, we should not send anything more
 228                          */
 229
 230                         wsi->state = WSI_STATE_AWAITING_CLOSE_ACK;
 231
 232                         /* and we should wait for a reply for a bit */
 233
 234                         libwebsocket_set_timeout(wsi,
 235                                                   PENDING_TIMEOUT_CLOSE_ACK, 5);
 236
 237                         fprintf(stderr, "sent close indication, awaiting ack\n");
 238
 239                         return;
 240                 }
 241
 242                 /* else, the send failed and we should just hang up */
 243         }
 244
 245 just_kill_connection:
 246         /*
 247          * we won't be servicing or receiving anything further from this guy
 248          * remove this fd from wsi mapping hashtable
 249          */
 250
 251         delete_from_fd(context, wsi->sock);
 252
 253         /* delete it from the internal poll list if still present */
 254
 255         for (n = 0; n < context->fds_count; n++) {
 256                 if (context->fds[n].fd != wsi->sock)
 257                         continue;
 258                 while (n < context->fds_count - 1) {
 259                         context->fds[n] = context->fds[n + 1];
 260                         n++;
 261                 }
 262                 context->fds_count--;
 263                 /* we only have to deal with one */
 264                 n = context->fds_count;
 265         }
 266
 267         /* remove also from external POLL support via protocol 0 */
 268
 269         context->protocols[0].callback(context, wsi,
 270                     LWS_CALLBACK_DEL_POLL_FD, (void *)(long)wsi->sock, NULL, 0);
 271
 272         wsi->state = WSI_STATE_DEAD_SOCKET;
 273
 274         /* tell the user it's all over for this guy */
 275
 276         if (wsi->protocol && wsi->protocol->callback &&
 277                                              old_state == WSI_STATE_ESTABLISHED)
 278                 wsi->protocol->callback(context, wsi, LWS_CALLBACK_CLOSED,
 279                                                       wsi->user_space, NULL, 0);
 280
 281         /* deallocate any active extension contexts */
 282
 283         for (n = 0; n < wsi->count_active_extensions; n++) {
 284                 if (!wsi->active_extensions[n]->callback)
 285                         continue;
 286
 287                 wsi->active_extensions[n]->callback(context, wsi,
 288                         LWS_EXT_CALLBACK_DESTROY,
 289                         wsi->active_extensions_user[n], NULL, 0);
 290
 291                 free(wsi->active_extensions_user[n]);
 292         }
 293
 294         /* free up his parsing allocations */
 295
 296         for (n = 0; n < WSI_TOKEN_COUNT; n++)
 297                 if (wsi->utf8_token[n].token)
 298                         free(wsi->utf8_token[n].token);
 299
 300 /*      fprintf(stderr, "closing fd=%d\n", wsi->sock); */
 301
 302 #ifdef LWS_OPENSSL_SUPPORT
 303         if (wsi->ssl) {
 304                 n = SSL_get_fd(wsi->ssl);
 305                 SSL_shutdown(wsi->ssl);
 306 #ifdef WIN32
 307                 closesocket(n);
 308 #else
 309                 close(n);
 310 #endif
 311                 SSL_free(wsi->ssl);
 312         } else {
 313 #endif
 314                 shutdown(wsi->sock, SHUT_RDWR);
 315 #ifdef WIN32
 316                 closesocket(wsi->sock);
 317 #else
 318                 close(wsi->sock);
 319 #endif
 320 #ifdef LWS_OPENSSL_SUPPORT
 321         }
 322 #endif
 323         if (wsi->user_space)
 324                 free(wsi->user_space);
 325
 326         free(wsi);
 327 }
 328
 329 /**
 330  * libwebsockets_hangup_on_client() - Server calls to terminate client
 331  *                                      connection
 332  * @context:    libwebsockets context
 333  * @fd:         Connection socket descriptor
 334  */
 335
 336 void
 337 libwebsockets_hangup_on_client(struct libwebsocket_context *context, int fd)
 338 {
 339         struct libwebsocket *wsi = wsi_from_fd(context, fd);
 340
 341         if (wsi == NULL)
 342                 return;
 343
 344         libwebsocket_close_and_free_session(context, wsi,
 345                                                      LWS_CLOSE_STATUS_NOSTATUS);
 346 }
 347
 348
 349 /**
 350  * libwebsockets_get_peer_addresses() - Get client address information
 351  * @fd:         Connection socket descriptor
 352  * @name:       Buffer to take client address name
 353  * @name_len:   Length of client address name buffer
 354  * @rip:        Buffer to take client address IP qotted quad
 355  * @rip_len:    Length of client address IP buffer
 356  *
 357  *      This function fills in @name and @rip with the name and IP of
 358  *      the client connected with socket descriptor @fd.  Names may be
 359  *      truncated if there is not enough room.  If either cannot be
 360  *      determined, they will be returned as valid zero-length strings.
 361  */
 362
 363 void
 364 libwebsockets_get_peer_addresses(int fd, char *name, int name_len,
 365                                         char *rip, int rip_len)
 366 {
 367         unsigned int len;
 368         struct sockaddr_in sin;
 369         struct hostent *host;
 370         struct hostent *host1;
 371         char ip[128];
 372         char *p;
 373         int n;
 374
 375         rip[0] = '\0';
 376         name[0] = '\0';
 377
 378         len = sizeof sin;
 379         if (getpeername(fd, (struct sockaddr *) &sin, &len) < 0) {
 380                 perror("getpeername");
 381                 return;
 382         }
 383
 384         host = gethostbyaddr((char *) &sin.sin_addr, sizeof sin.sin_addr,
 385                                                                        AF_INET);
 386         if (host == NULL) {
 387                 perror("gethostbyaddr");
 388                 return;
 389         }
 390
 391         strncpy(name, host->h_name, name_len);
 392         name[name_len - 1] = '\0';
 393
 394         host1 = gethostbyname(host->h_name);
 395         if (host1 == NULL)
 396                 return;
 397         p = (char *)host1;
 398         n = 0;
 399         while (p != NULL) {
 400                 p = host1->h_addr_list[n++];
 401                 if (p == NULL)
 402                         continue;
 403                 if (host1->h_addrtype != AF_INET)
 404                         continue;
 405
 406                 sprintf(ip, "%d.%d.%d.%d",
 407                                 p[0], p[1], p[2], p[3]);
 408                 p = NULL;
 409                 strncpy(rip, ip, rip_len);
 410                 rip[rip_len - 1] = '\0';
 411         }
 412 }
 413
 414 int libwebsockets_get_random(struct libwebsocket_context *context,
 415                                                              void *buf, int len)
 416 {
 417         int n;
 418         char *p = buf;
 419
 420 #ifdef WIN32
 421         for (n = 0; n < len; n++)
 422                 p[n] = (unsigned char)rand();
 423 #else
 424         n = read(context->fd_random, p, len);
 425 #endif
 426
 427         return n;
 428 }
 429
 430 void libwebsockets_00_spaceout(char *key, int spaces, int seed)
 431 {
 432         char *p;
 433
 434         key++;
 435         while (spaces--) {
 436                 if (*key && (seed & 1))
 437                         key++;
 438                 seed >>= 1;
 439
 440                 p = key + strlen(key);
 441                 while (p >= key) {
 442                         p[1] = p[0];
 443                         p--;
 444                 }
 445                 *key++ = ' ';
 446         }
 447 }
 448
 449 void libwebsockets_00_spam(char *key, int count, int seed)
 450 {
 451         char *p;
 452
 453         key++;
 454         while (count--) {
 455
 456                 if (*key && (seed & 1))
 457                         key++;
 458                 seed >>= 1;
 459
 460                 p = key + strlen(key);
 461                 while (p >= key) {
 462                         p[1] = p[0];
 463                         p--;
 464                 }
 465                 *key++ = 0x21 + ((seed & 0xffff) % 15);
 466                 /* 4 would use it up too fast.. not like it matters */
 467                 seed >>= 1;
 468         }
 469 }
 470
 471 int lws_send_pipe_choked(struct libwebsocket *wsi)
 472 {
 473         struct pollfd fds;
 474
 475         fds.fd = wsi->sock;
 476         fds.events = POLLOUT;
 477         fds.revents = 0;
 478
 479         if (poll(&fds, 1, 0) != 1)
 480                 return 1;
 481
 482         if ((fds.revents & POLLOUT) == 0)
 483                 return 1;
 484
 485         /* okay to send another packet without blocking */
 486
 487         return 0;
 488 }
 489
 490 static int
 491 lws_handle_POLLOUT_event(struct libwebsocket_context *context,
 492                                 struct libwebsocket *wsi, struct pollfd *pollfd)
 493 {
 494         struct lws_tokens eff_buf;
 495         int n;
 496         int ret;
 497         int m;
 498
 499         if (!wsi->extension_data_pending)
 500                 goto user_service;
 501
 502         /*
 503          * check in on the active extensions, see if they
 504          * had pending stuff to spill... they need to get the
 505          * first look-in otherwise sequence will be disordered
 506          *
 507          * NULL, zero-length eff_buf means just spill pending
 508          */
 509
 510         ret = 1;
 511         while (ret == 1) {
 512
 513                 /* default to nobody has more to spill */
 514
 515                 ret = 0;
 516                 eff_buf.token = NULL;
 517                 eff_buf.token_len = 0;
 518
 519                 /* give every extension a chance to spill */
 520
 521                 for (n = 0; n < wsi->count_active_extensions; n++) {
 522                         m = wsi->active_extensions[n]->callback(
 523                                 wsi->protocol->owning_server, wsi,
 524                                         LWS_EXT_CALLBACK_PACKET_TX_PRESEND,
 525                                    wsi->active_extensions_user[n], &eff_buf, 0);
 526                         if (m < 0) {
 527                                 fprintf(stderr, "extension reports fatal error\n");
 528                                 return -1;
 529                         }
 530                         if (m)
 531                                 /*
 532                                  * at least one extension told us he has more
 533                                  * to spill, so we will go around again after
 534                                  */
 535                                 ret = 1;
 536                 }
 537
 538                 /* assuming they gave us something to send, send it */
 539
 540                 if (eff_buf.token_len) {
 541                         if (lws_issue_raw(wsi, (unsigned char *)eff_buf.token,
 542                                                              eff_buf.token_len))
 543                                 return -1;
 544                 } else
 545                         continue;
 546
 547                 /* no extension has more to spill */
 548
 549                 if (!ret)
 550                         continue;
 551
 552                 /*
 553                  * There's more to spill from an extension, but we just sent
 554                  * something... did that leave the pipe choked?
 555                  */
 556
 557                 if (!lws_send_pipe_choked(wsi))
 558                         /* no we could add more */
 559                         continue;
 560
 561                 fprintf(stderr, "choked in POLLOUT service\n");
 562
 563                 /*
 564                  * Yes, he's choked.  Leave the POLLOUT masked on so we will
 565                  * come back here when he is unchoked.  Don't call the user
 566                  * callback to enforce ordering of spilling, he'll get called
 567                  * when we come back here and there's nothing more to spill.
 568                  */
 569
 570                 return 0;
 571         }
 572
 573         wsi->extension_data_pending = 0;
 574
 575 user_service:
 576         /* one shot */
 577
 578         pollfd->events &= ~POLLOUT;
 579
 580         /* external POLL support via protocol 0 */
 581         context->protocols[0].callback(context, wsi,
 582                 LWS_CALLBACK_CLEAR_MODE_POLL_FD,
 583                 (void *)(long)wsi->sock, NULL, POLLOUT);
 584
 585         if (wsi->mode == LWS_CONNMODE_WS_CLIENT)
 586                 n = LWS_CALLBACK_CLIENT_WRITEABLE;
 587         else
 588                 n = LWS_CALLBACK_SERVER_WRITEABLE;
 589
 590         wsi->protocol->callback(context, wsi, n, wsi->user_space, NULL, 0);
 591
 592         return 0;
 593 }
 594
 595
 596
 597 /**
 598  * libwebsocket_service_fd() - Service polled socket with something waiting
 599  * @context:    Websocket context
 600  * @pollfd:     The pollfd entry describing the socket fd and which events
 601  *              happened.
 602  *
 603  *      This function closes any active connections and then frees the
 604  *      context.  After calling this, any further use of the context is
 605  *      undefined.
 606  */
 607
 608 int
 609 libwebsocket_service_fd(struct libwebsocket_context *context,
 610                                                           struct pollfd *pollfd)
 611 {
 612         unsigned char buf[LWS_SEND_BUFFER_PRE_PADDING + 1 + MAX_BROADCAST_PAYLOAD +
 613                                                   LWS_SEND_BUFFER_POST_PADDING];
 614         struct libwebsocket *wsi;
 615         struct libwebsocket *new_wsi;
 616         int n;
 617         int m;
 618         size_t len;
 619         int accept_fd;
 620         unsigned int clilen;
 621         struct sockaddr_in cli_addr;
 622         struct timeval tv;
 623         static const char magic_websocket_guid[] =
 624                                          "258EAFA5-E914-47DA-95CA-C5AB0DC85B11";
 625         static const char magic_websocket_04_masking_guid[] =
 626                                          "61AC5F19-FBBA-4540-B96F-6561F1AB40A8";
 627         char hash[20];
 628         char pkt[1024];
 629         char *p = &pkt[0];
 630         const char *pc;
 631         const char *c;
 632         int more = 1;
 633         int okay = 0;
 634         char ext_name[128];
 635         struct lws_tokens eff_buf;
 636         int ext_count = 0;
 637         struct libwebsocket_extension *ext;
 638
 639 #ifdef LWS_OPENSSL_SUPPORT
 640         char ssl_err_buf[512];
 641 #endif
 642         /*
 643          * you can call us with pollfd = NULL to just allow the once-per-second
 644          * global timeout checks; if less than a second since the last check
 645          * it returns immediately then.
 646          */
 647
 648         gettimeofday(&tv, NULL);
 649
 650         if (context->last_timeout_check_s != tv.tv_sec) {
 651                 context->last_timeout_check_s = tv.tv_sec;
 652
 653                 /* global timeout check once per second */
 654
 655                 for (n = 0; n < context->fds_count; n++) {
 656                         wsi = wsi_from_fd(context, context->fds[n].fd);
 657                         if (!wsi->pending_timeout)
 658                                 continue;
 659
 660                         /*
 661                          * if we went beyond the allowed time, kill the
 662                          * connection
 663                          */
 664
 665                         if (tv.tv_sec > wsi->pending_timeout_limit) {
 666                                 fprintf(stderr, "TIMEDOUT WAITING\n");
 667                                 libwebsocket_close_and_free_session(context,
 668                                                 wsi, LWS_CLOSE_STATUS_NOSTATUS);
 669                         }
 670                 }
 671         }
 672
 673         /* just here for timeout management? */
 674
 675         if (pollfd == NULL)
 676                 return 0;
 677
 678         /* no, here to service a socket descriptor */
 679
 680         wsi = wsi_from_fd(context, pollfd->fd);
 681
 682         if (wsi == NULL)
 683                 return 1;
 684
 685         switch (wsi->mode) {
 686         case LWS_CONNMODE_SERVER_LISTENER:
 687
 688                 /* pollin means a client has connected to us then */
 689
 690                 if (!pollfd->revents & POLLIN)
 691                         break;
 692
 693                 /* listen socket got an unencrypted connection... */
 694
 695                 clilen = sizeof(cli_addr);
 696                 accept_fd  = accept(pollfd->fd, (struct sockaddr *)&cli_addr,
 697                                                                        &clilen);
 698                 if (accept_fd < 0) {
 699                         fprintf(stderr, "ERROR on accept");
 700                         break;
 701                 }
 702
 703                 if (context->fds_count >= MAX_CLIENTS) {
 704                         fprintf(stderr, "too busy to accept new client\n");
 705 #ifdef WIN32
 706                         closesocket(accept_fd);
 707 #else
 708                         close(accept_fd);
 709 #endif
 710                         break;
 711                 }
 712
 713                 /*
 714                  * look at who we connected to and give user code a chance
 715                  * to reject based on client IP.  There's no protocol selected
 716                  * yet so we issue this to protocols[0]
 717                  */
 718
 719                 if ((context->protocols[0].callback)(context, wsi,
 720                                 LWS_CALLBACK_FILTER_NETWORK_CONNECTION,
 721                                              (void*)(long)accept_fd, NULL, 0)) {
 722                         fprintf(stderr, "Callback denied network connection\n");
 723 #ifdef WIN32
 724                         closesocket(accept_fd);
 725 #else
 726                         close(accept_fd);
 727 #endif
 728                         break;
 729                 }
 730
 731                 /* accepting connection to main listener */
 732
 733                 new_wsi = malloc(sizeof(struct libwebsocket));
 734                 if (new_wsi == NULL) {
 735                         fprintf(stderr, "Out of memory for new connection\n");
 736                         break;
 737                 }
 738
 739                 memset(new_wsi, 0, sizeof (struct libwebsocket));
 740                 new_wsi->sock = accept_fd;
 741                 new_wsi->count_active_extensions = 0;
 742                 new_wsi->pending_timeout = NO_PENDING_TIMEOUT;
 743
 744 #ifdef LWS_OPENSSL_SUPPORT
 745                 new_wsi->ssl = NULL;
 746
 747                 if (context->use_ssl) {
 748
 749                         new_wsi->ssl = SSL_new(context->ssl_ctx);
 750                         if (new_wsi->ssl == NULL) {
 751                                 fprintf(stderr, "SSL_new failed: %s\n",
 752                                     ERR_error_string(SSL_get_error(
 753                                     new_wsi->ssl, 0), NULL));
 754                                     libwebsockets_decode_ssl_error();
 755                                 free(new_wsi);
 756                                 break;
 757                         }
 758
 759                         SSL_set_fd(new_wsi->ssl, accept_fd);
 760
 761                         n = SSL_accept(new_wsi->ssl);
 762                         if (n != 1) {
 763                                 /*
 764                                  * browsers seem to probe with various
 765                                  * ssl params which fail then retry
 766                                  * and succeed
 767                                  */
 768                                 debug("SSL_accept failed skt %u: %s\n",
 769                                       pollfd->fd,
 770                                       ERR_error_string(SSL_get_error(
 771                                       new_wsi->ssl, n), NULL));
 772                                 SSL_free(
 773                                        new_wsi->ssl);
 774                                 free(new_wsi);
 775                                 break;
 776                         }
 777
 778                         debug("accepted new SSL conn  "
 779                               "port %u on fd=%d SSL ver %s\n",
 780                                 ntohs(cli_addr.sin_port), accept_fd,
 781                                   SSL_get_version(new_wsi->ssl));
 782
 783                 } else
 784 #endif
 785                         debug("accepted new conn  port %u on fd=%d\n",
 786                                           ntohs(cli_addr.sin_port), accept_fd);
 787
 788                 /* intialize the instance struct */
 789
 790                 new_wsi->state = WSI_STATE_HTTP;
 791                 new_wsi->name_buffer_pos = 0;
 792                 new_wsi->mode = LWS_CONNMODE_WS_SERVING;
 793
 794                 for (n = 0; n < WSI_TOKEN_COUNT; n++) {
 795                         new_wsi->utf8_token[n].token = NULL;
 796                         new_wsi->utf8_token[n].token_len = 0;
 797                 }
 798
 799                 /*
 800                  * these can only be set once the protocol is known
 801                  * we set an unestablished connection's protocol pointer
 802                  * to the start of the supported list, so it can look
 803                  * for matching ones during the handshake
 804                  */
 805                 new_wsi->protocol = context->protocols;
 806                 new_wsi->user_space = NULL;
 807
 808                 /*
 809                  * Default protocol is 76 / 00
 810                  * After 76, there's a header specified to inform which
 811                  * draft the client wants, when that's seen we modify
 812                  * the individual connection's spec revision accordingly
 813                  */
 814                 new_wsi->ietf_spec_revision = 0;
 815
 816                 insert_wsi(context, new_wsi);
 817
 818                 /*
 819                  * make sure NO events are seen yet on this new socket
 820                  * (otherwise we inherit old fds[client].revents from
 821                  * previous socket there and die mysteriously! )
 822                  */
 823                 context->fds[context->fds_count].revents = 0;
 824
 825                 context->fds[context->fds_count].events = POLLIN;
 826                 context->fds[context->fds_count++].fd = accept_fd;
 827
 828                 /* external POLL support via protocol 0 */
 829                 context->protocols[0].callback(context, new_wsi,
 830                         LWS_CALLBACK_ADD_POLL_FD,
 831                         (void *)(long)accept_fd, NULL, POLLIN);
 832
 833                 break;
 834
 835         case LWS_CONNMODE_BROADCAST_PROXY_LISTENER:
 836
 837                 /* as we are listening, POLLIN means accept() is needed */
 838
 839                 if (!pollfd->revents & POLLIN)
 840                         break;
 841
 842                 /* listen socket got an unencrypted connection... */
 843
 844                 clilen = sizeof(cli_addr);
 845                 accept_fd  = accept(pollfd->fd, (struct sockaddr *)&cli_addr,
 846                                                                        &clilen);
 847                 if (accept_fd < 0) {
 848                         fprintf(stderr, "ERROR on accept");
 849                         break;
 850                 }
 851
 852                 if (context->fds_count >= MAX_CLIENTS) {
 853                         fprintf(stderr, "too busy to accept new broadcast "
 854                                                               "proxy client\n");
 855 #ifdef WIN32
 856                         closesocket(accept_fd);
 857 #else
 858                         close(accept_fd);
 859 #endif
 860                         break;
 861                 }
 862
 863                 /* create a dummy wsi for the connection and add it */
 864
 865                 new_wsi = malloc(sizeof(struct libwebsocket));
 866                 memset(new_wsi, 0, sizeof (struct libwebsocket));
 867                 new_wsi->sock = accept_fd;
 868                 new_wsi->mode = LWS_CONNMODE_BROADCAST_PROXY;
 869                 new_wsi->state = WSI_STATE_ESTABLISHED;
 870                 new_wsi->count_active_extensions = 0;
 871                 /* note which protocol we are proxying */
 872                 new_wsi->protocol_index_for_broadcast_proxy =
 873                                         wsi->protocol_index_for_broadcast_proxy;
 874                 insert_wsi(context, new_wsi);
 875
 876                 /* add connected socket to internal poll array */
 877
 878                 context->fds[context->fds_count].revents = 0;
 879                 context->fds[context->fds_count].events = POLLIN;
 880                 context->fds[context->fds_count++].fd = accept_fd;
 881
 882                 /* external POLL support via protocol 0 */
 883                 context->protocols[0].callback(context, new_wsi,
 884                         LWS_CALLBACK_ADD_POLL_FD,
 885                         (void *)(long)accept_fd, NULL, POLLIN);
 886
 887                 break;
 888
 889         case LWS_CONNMODE_BROADCAST_PROXY:
 890
 891                 /* handle session socket closed */
 892
 893                 if (pollfd->revents & (POLLERR | POLLHUP)) {
 894
 895                         debug("Session Socket %p (fd=%d) dead\n",
 896                                 (void *)wsi, pollfd->fd);
 897
 898                         libwebsocket_close_and_free_session(context, wsi,
 899                                                        LWS_CLOSE_STATUS_NORMAL);
 900                         return 1;
 901                 }
 902
 903                 /*
 904                  * either extension code with stuff to spill, or the user code,
 905                  * requested a callback when it was OK to write
 906                  */
 907
 908                 if (pollfd->revents & POLLOUT)
 909                         if (lws_handle_POLLOUT_event(context, wsi, pollfd) < 0) {
 910                                 libwebsocket_close_and_free_session(context, wsi,
 911                                                        LWS_CLOSE_STATUS_NORMAL);
 912                                 return 1;
 913                         }
 914
 915                 /* any incoming data ready? */
 916
 917                 if (!(pollfd->revents & POLLIN))
 918                         break;
 919
 920                 /* get the issued broadcast payload from the socket */
 921
 922                 len = read(pollfd->fd, buf + LWS_SEND_BUFFER_PRE_PADDING,
 923                                                          MAX_BROADCAST_PAYLOAD);
 924                 if (len < 0) {
 925                         fprintf(stderr, "Error reading broadcast payload\n");
 926                         break;
 927                 }
 928
 929                 /* broadcast it to all guys with this protocol index */
 930
 931                 for (n = 0; n < FD_HASHTABLE_MODULUS; n++) {
 932
 933                         for (m = 0; m < context->fd_hashtable[n].length; m++) {
 934
 935                                 new_wsi = context->fd_hashtable[n].wsi[m];
 936
 937                                 /* only to clients we are serving to */
 938
 939                                 if (new_wsi->mode != LWS_CONNMODE_WS_SERVING)
 940                                         continue;
 941
 942                                 /*
 943                                  * never broadcast to non-established
 944                                  * connection
 945                                  */
 946
 947                                 if (new_wsi->state != WSI_STATE_ESTABLISHED)
 948                                         continue;
 949
 950                                 /*
 951                                  * only broadcast to connections using
 952                                  * the requested protocol
 953                                  */
 954
 955                                 if (new_wsi->protocol->protocol_index !=
 956                                         wsi->protocol_index_for_broadcast_proxy)
 957                                         continue;
 958
 959                                 /* broadcast it to this connection */
 960
 961                                 new_wsi->protocol->callback(context, new_wsi,
 962                                         LWS_CALLBACK_BROADCAST,
 963                                         new_wsi->user_space,
 964                                         buf + LWS_SEND_BUFFER_PRE_PADDING, len);
 965                         }
 966                 }
 967                 break;
 968
 969         case LWS_CONNMODE_WS_CLIENT_WAITING_PROXY_REPLY:
 970
 971                 /* handle proxy hung up on us */
 972
 973                 if (pollfd->revents & (POLLERR | POLLHUP)) {
 974
 975                         fprintf(stderr, "Proxy connection %p (fd=%d) dead\n",
 976                                 (void *)wsi, pollfd->fd);
 977
 978                         libwebsocket_close_and_free_session(context, wsi,
 979                                                      LWS_CLOSE_STATUS_NOSTATUS);
 980                         return 1;
 981                 }
 982
 983                 n = recv(wsi->sock, pkt, sizeof pkt, 0);
 984                 if (n < 0) {
 985                         libwebsocket_close_and_free_session(context, wsi,
 986                                                      LWS_CLOSE_STATUS_NOSTATUS);
 987                         fprintf(stderr, "ERROR reading from proxy socket\n");
 988                         return 1;
 989                 }
 990
 991                 pkt[13] = '\0';
 992                 if (strcmp(pkt, "HTTP/1.0 200 ") != 0) {
 993                         libwebsocket_close_and_free_session(context, wsi,
 994                                                      LWS_CLOSE_STATUS_NOSTATUS);
 995                         fprintf(stderr, "ERROR from proxy: %s\n", pkt);
 996                         return 1;
 997                 }
 998
 999                 /* clear his proxy connection timeout */
1000
1001                 libwebsocket_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
1002
1003                 /* fallthru */
1004
1005         case LWS_CONNMODE_WS_CLIENT_ISSUE_HANDSHAKE:
1006
1007         #ifdef LWS_OPENSSL_SUPPORT
1008                 if (wsi->use_ssl) {
1009
1010                         wsi->ssl = SSL_new(context->ssl_client_ctx);
1011                         wsi->client_bio = BIO_new_socket(wsi->sock,
1012                                                                    BIO_NOCLOSE);
1013                         SSL_set_bio(wsi->ssl, wsi->client_bio, wsi->client_bio);
1014
1015                         SSL_set_ex_data(wsi->ssl,
1016                                         openssl_websocket_private_data_index,
1017                                                                        context);
1018
1019                         if (SSL_connect(wsi->ssl) <= 0) {
1020                                 fprintf(stderr, "SSL connect error %s\n",
1021                                         ERR_error_string(ERR_get_error(),
1022                                                                   ssl_err_buf));
1023                                 libwebsocket_close_and_free_session(context, wsi,
1024                                                      LWS_CLOSE_STATUS_NOSTATUS);
1025                                 return 1;
1026                         }
1027
1028                         n = SSL_get_verify_result(wsi->ssl);
1029                         if ((n != X509_V_OK) && (
1030                                 n != X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT ||
1031                                                            wsi->use_ssl != 2)) {
1032
1033                                 fprintf(stderr, "server's cert didn't "
1034                                                            "look good %d\n", n);
1035                                 libwebsocket_close_and_free_session(context,
1036                                                 wsi, LWS_CLOSE_STATUS_NOSTATUS);
1037                                 return 1;
1038                         }
1039                 } else {
1040                         wsi->ssl = NULL;
1041         #endif
1042
1043
1044         #ifdef LWS_OPENSSL_SUPPORT
1045                 }
1046         #endif
1047
1048                 /*
1049                  * create the random key
1050                  */
1051
1052                 n = libwebsockets_get_random(context, hash, 16);
1053                 if (n != 16) {
1054                         fprintf(stderr, "Unable to read from random dev %s\n",
1055                                                         SYSTEM_RANDOM_FILEPATH);
1056                         free(wsi->c_path);
1057                         free(wsi->c_host);
1058                         if (wsi->c_origin)
1059                                 free(wsi->c_origin);
1060                         if (wsi->c_protocol)
1061                                 free(wsi->c_protocol);
1062                         libwebsocket_close_and_free_session(context, wsi,
1063                                                      LWS_CLOSE_STATUS_NOSTATUS);
1064                         return 1;
1065                 }
1066
1067                 lws_b64_encode_string(hash, 16, wsi->key_b64,
1068                                                            sizeof wsi->key_b64);
1069
1070                 /*
1071                  * 00 example client handshake
1072                  *
1073                  * GET /socket.io/websocket HTTP/1.1
1074                  * Upgrade: WebSocket
1075                  * Connection: Upgrade
1076                  * Host: 127.0.0.1:9999
1077                  * Origin: http://127.0.0.1
1078                  * Sec-WebSocket-Key1: 1 0 2#0W 9 89 7  92 ^
1079                  * Sec-WebSocket-Key2: 7 7Y 4328 B2v[8(z1
1080                  * Cookie: socketio=websocket
1081                  *
1082                  * (Á®Ä0¶†≥
1083                  *
1084                  * 04 example client handshake
1085                  *
1086                  * GET /chat HTTP/1.1
1087                  * Host: server.example.com
1088                  * Upgrade: websocket
1089                  * Connection: Upgrade
1090                  * Sec-WebSocket-Key: dGhlIHNhbXBsZSBub25jZQ==
1091                  * Sec-WebSocket-Origin: http://example.com
1092                  * Sec-WebSocket-Protocol: chat, superchat
1093                  * Sec-WebSocket-Version: 4
1094                  */
1095
1096                 p += sprintf(p, "GET %s HTTP/1.1\x0d\x0a", wsi->c_path);
1097
1098                 if (wsi->ietf_spec_revision == 0) {
1099                         unsigned char spaces_1, spaces_2;
1100                         unsigned int max_1, max_2;
1101                         unsigned int num_1, num_2;
1102                         unsigned long product_1, product_2;
1103                         char key_1[40];
1104                         char key_2[40];
1105                         unsigned int seed;
1106                         unsigned int count;
1107                         char challenge[16];
1108
1109                         libwebsockets_get_random(context, &spaces_1,
1110                                                                   sizeof(char));
1111                         libwebsockets_get_random(context, &spaces_2,
1112                                                                   sizeof(char));
1113
1114                         spaces_1 = (spaces_1 % 12) + 1;
1115                         spaces_2 = (spaces_2 % 12) + 1;
1116
1117                         max_1 = 4294967295 / spaces_1;
1118                         max_2 = 4294967295 / spaces_2;
1119
1120                         libwebsockets_get_random(context, &num_1, sizeof(int));
1121                         libwebsockets_get_random(context, &num_2, sizeof(int));
1122
1123                         num_1 = (num_1 % max_1);
1124                         num_2 = (num_2 % max_2);
1125
1126                         challenge[0] = num_1 >> 24;
1127                         challenge[1] = num_1 >> 16;
1128                         challenge[2] = num_1 >> 8;
1129                         challenge[3] = num_1;
1130                         challenge[4] = num_2 >> 24;
1131                         challenge[5] = num_2 >> 16;
1132                         challenge[6] = num_2 >> 8;
1133                         challenge[7] = num_2;
1134
1135                         product_1 = num_1 * spaces_1;
1136                         product_2 = num_2 * spaces_2;
1137
1138                         sprintf(key_1, "%lu", product_1);
1139                         sprintf(key_2, "%lu", product_2);
1140
1141                         libwebsockets_get_random(context, &seed, sizeof(int));
1142                         libwebsockets_get_random(context, &count, sizeof(int));
1143
1144                         libwebsockets_00_spam(key_1, (count % 12) + 1, seed);
1145
1146                         libwebsockets_get_random(context, &seed, sizeof(int));
1147                         libwebsockets_get_random(context, &count, sizeof(int));
1148
1149                         libwebsockets_00_spam(key_2, (count % 12) + 1, seed);
1150
1151                         libwebsockets_get_random(context, &seed, sizeof(int));
1152
1153                         libwebsockets_00_spaceout(key_1, spaces_1, seed);
1154                         libwebsockets_00_spaceout(key_2, spaces_2, seed >> 16);
1155
1156                         p += sprintf(p, "Upgrade: websocket\x0d\x0a"
1157                                 "Connection: Upgrade\x0d\x0aHost: %s\x0d\x0a",
1158                                 wsi->c_host);
1159                         if (wsi->c_origin)
1160                                 p += sprintf(p, "Origin: %s\x0d\x0a",
1161                                 wsi->c_origin);
1162
1163                         if (wsi->c_protocol)
1164                                 p += sprintf(p, "Sec-WebSocket-Protocol: %s"
1165                                                  "\x0d\x0a", wsi->c_protocol);
1166
1167                         p += sprintf(p, "Sec-WebSocket-Key1: %s\x0d\x0a",
1168                                 key_1);
1169                         p += sprintf(p, "Sec-WebSocket-Key2: %s\x0d\x0a",
1170                                 key_2);
1171
1172                         /* give userland a chance to append, eg, cookies */
1173
1174                         context->protocols[0].callback(context, wsi,
1175                                 LWS_CALLBACK_CLIENT_APPEND_HANDSHAKE_HEADER,
1176                                         NULL, &p, (pkt + sizeof(pkt)) - p - 12);
1177
1178                         p += sprintf(p, "\x0d\x0a");
1179
1180                         read(context->fd_random, p, 8);
1181                         memcpy(&challenge[8], p, 8);
1182                         p += 8;
1183
1184                         /* precompute what we want to see from the server */
1185
1186                         MD5((unsigned char *)challenge, 16,
1187                            (unsigned char *)wsi->initial_handshake_hash_base64);
1188
1189                         goto issue_hdr;
1190                 }
1191
1192                 p += sprintf(p, "Host: %s\x0d\x0a", wsi->c_host);
1193                 p += sprintf(p, "Upgrade: websocket\x0d\x0a");
1194                 p += sprintf(p, "Connection: Upgrade\x0d\x0a"
1195                                         "Sec-WebSocket-Key: ");
1196                 strcpy(p, wsi->key_b64);
1197                 p += strlen(wsi->key_b64);
1198                 p += sprintf(p, "\x0d\x0a");
1199                 if (wsi->c_origin)
1200                         p += sprintf(p, "Sec-WebSocket-Origin: %s\x0d\x0a",
1201                                                                  wsi->c_origin);
1202                 if (wsi->c_protocol)
1203                         p += sprintf(p, "Sec-WebSocket-Protocol: %s\x0d\x0a",
1204                                                                wsi->c_protocol);
1205
1206                 /* tell the server what extensions we could support */
1207
1208                 p += sprintf(p, "Sec-WebSocket-Extensions: ");
1209
1210                 ext =context->extensions;
1211                 while (ext && ext->callback) {
1212
1213                         n = 0;
1214                         n = context->protocols[0].callback(context, wsi,
1215                                 LWS_CALLBACK_CLIENT_CONFIRM_EXTENSION_SUPPORTED,
1216                                         wsi->user_space, (char *)ext->name, 0);
1217
1218                         /*
1219                          * zero return from callback means
1220                          * go ahead and allow the extension,
1221                          * it's what we get if the callback is
1222                          * unhandled
1223                          */
1224
1225                         if (n) {
1226                                 ext++;
1227                                 continue;
1228                         }
1229
1230                         /* apply it */
1231
1232                         if (ext_count)
1233                                 *p++ = ',';
1234                         p += sprintf(p, ext->name);
1235                         ext_count++;
1236
1237                         ext++;
1238                 }
1239
1240                 p += sprintf(p, "\x0d\x0a");
1241
1242                 if (wsi->ietf_spec_revision)
1243                         p += sprintf(p, "Sec-WebSocket-Version: %d\x0d\x0a",
1244                                                        wsi->ietf_spec_revision);
1245
1246                 /* give userland a chance to append, eg, cookies */
1247
1248                 context->protocols[0].callback(context, wsi,
1249                         LWS_CALLBACK_CLIENT_APPEND_HANDSHAKE_HEADER,
1250                         NULL, &p, (pkt + sizeof(pkt)) - p - 12);
1251
1252                 p += sprintf(p, "\x0d\x0a");
1253
1254                 /* prepare the expected server accept response */
1255
1256                 strcpy((char *)buf, wsi->key_b64);
1257                 strcpy((char *)&buf[strlen((char *)buf)], magic_websocket_guid);
1258
1259                 SHA1(buf, strlen((char *)buf), (unsigned char *)hash);
1260
1261                 lws_b64_encode_string(hash, 20,
1262                                 wsi->initial_handshake_hash_base64,
1263                                      sizeof wsi->initial_handshake_hash_base64);
1264
1265 issue_hdr:
1266
1267                 /* done with these now */
1268
1269                 free(wsi->c_path);
1270                 free(wsi->c_host);
1271                 if (wsi->c_origin)
1272                         free(wsi->c_origin);
1273
1274                 /* send our request to the server */
1275
1276         #ifdef LWS_OPENSSL_SUPPORT
1277                 if (wsi->use_ssl)
1278                         n = SSL_write(wsi->ssl, pkt, p - pkt);
1279                 else
1280         #endif
1281                         n = send(wsi->sock, pkt, p - pkt, 0);
1282
1283                 if (n < 0) {
1284                         fprintf(stderr, "ERROR writing to client socket\n");
1285                         libwebsocket_close_and_free_session(context, wsi,
1286                                                      LWS_CLOSE_STATUS_NOSTATUS);
1287                         return 1;
1288                 }
1289
1290                 wsi->parser_state = WSI_TOKEN_NAME_PART;
1291                 wsi->mode = LWS_CONNMODE_WS_CLIENT_WAITING_SERVER_REPLY;
1292                 libwebsocket_set_timeout(wsi,
1293                                 PENDING_TIMEOUT_AWAITING_SERVER_RESPONSE, 5);
1294
1295                 break;
1296
1297         case LWS_CONNMODE_WS_CLIENT_WAITING_SERVER_REPLY:
1298
1299                 /* handle server hung up on us */
1300
1301                 if (pollfd->revents & (POLLERR | POLLHUP)) {
1302
1303                         fprintf(stderr, "Server connection %p (fd=%d) dead\n",
1304                                 (void *)wsi, pollfd->fd);
1305
1306                         goto bail3;
1307                 }
1308
1309
1310                 /* interpret the server response */
1311
1312                 /*
1313                  *  HTTP/1.1 101 Switching Protocols
1314                  *  Upgrade: websocket
1315                  *  Connection: Upgrade
1316                  *  Sec-WebSocket-Accept: me89jWimTRKTWwrS3aRrL53YZSo=
1317                  *  Sec-WebSocket-Nonce: AQIDBAUGBwgJCgsMDQ4PEC==
1318                  *  Sec-WebSocket-Protocol: chat
1319                  */
1320
1321         #ifdef LWS_OPENSSL_SUPPORT
1322                 if (wsi->use_ssl)
1323                         len = SSL_read(wsi->ssl, pkt, sizeof pkt);
1324                 else
1325         #endif
1326                         len = recv(wsi->sock, pkt, sizeof pkt, 0);
1327
1328                 if (len < 0) {
1329                         fprintf(stderr,
1330                                   "libwebsocket_client_handshake read error\n");
1331                         goto bail3;
1332                 }
1333
1334                 p = pkt;
1335                 for (n = 0; n < len; n++)
1336                         libwebsocket_parse(wsi, *p++);
1337
1338                 if (wsi->parser_state != WSI_PARSING_COMPLETE) {
1339                         fprintf(stderr, "libwebsocket_client_handshake "
1340                                         "server response failed parsing\n");
1341                         goto bail3;
1342                 }
1343
1344                 /*
1345                  * 00 / 76 -->
1346                  *
1347                  * HTTP/1.1 101 WebSocket Protocol Handshake
1348                  * Upgrade: WebSocket
1349                  * Connection: Upgrade
1350                  * Sec-WebSocket-Origin: http://127.0.0.1
1351                  * Sec-WebSocket-Location: ws://127.0.0.1:9999/socket.io/websocket
1352                  *
1353                  * xxxxxxxxxxxxxxxx
1354                  */
1355
1356                 if (wsi->ietf_spec_revision == 0) {
1357                         if (!wsi->utf8_token[WSI_TOKEN_HTTP].token_len ||
1358                             !wsi->utf8_token[WSI_TOKEN_UPGRADE].token_len ||
1359                             !wsi->utf8_token[WSI_TOKEN_CHALLENGE].token_len ||
1360                             !wsi->utf8_token[WSI_TOKEN_CONNECTION].token_len ||
1361                             (!wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len &&
1362                             wsi->c_protocol != NULL)) {
1363                                 fprintf(stderr, "libwebsocket_client_handshake "
1364                                                 "missing required header(s)\n");
1365                                 pkt[len] = '\0';
1366                                 fprintf(stderr, "%s", pkt);
1367                                 goto bail3;
1368                         }
1369
1370                         strtolower(wsi->utf8_token[WSI_TOKEN_HTTP].token);
1371                         if (strcmp(wsi->utf8_token[WSI_TOKEN_HTTP].token,
1372                                 "101 websocket protocol handshake")) {
1373                                 fprintf(stderr, "libwebsocket_client_handshake "
1374                                         "server sent bad HTTP response '%s'\n",
1375                                         wsi->utf8_token[WSI_TOKEN_HTTP].token);
1376                                 goto bail3;
1377                         }
1378
1379                         if (wsi->utf8_token[WSI_TOKEN_CHALLENGE].token_len <
1380                                                                            16) {
1381                                 fprintf(stderr, "libwebsocket_client_handshake "
1382                                         "challenge reply too short %d\n",
1383                                         wsi->utf8_token[
1384                                                 WSI_TOKEN_CHALLENGE].token_len);
1385                                 pkt[len] = '\0';
1386                                 fprintf(stderr, "%s", pkt);
1387                                 goto bail3;
1388
1389                         }
1390
1391                         goto select_protocol;
1392                 }
1393
1394                 /*
1395                  * well, what the server sent looked reasonable for syntax.
1396                  * Now let's confirm it sent all the necessary headers
1397                  */
1398
1399                  if (!wsi->utf8_token[WSI_TOKEN_HTTP].token_len ||
1400                         !wsi->utf8_token[WSI_TOKEN_UPGRADE].token_len ||
1401                         !wsi->utf8_token[WSI_TOKEN_CONNECTION].token_len ||
1402                         !wsi->utf8_token[WSI_TOKEN_ACCEPT].token_len ||
1403                         (!wsi->utf8_token[WSI_TOKEN_NONCE].token_len &&
1404                                            wsi->ietf_spec_revision == 4) ||
1405                         (!wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len &&
1406                                                      wsi->c_protocol != NULL)) {
1407                         fprintf(stderr, "libwebsocket_client_handshake "
1408                                                 "missing required header(s)\n");
1409                         pkt[len] = '\0';
1410                         fprintf(stderr, "%s", pkt);
1411                         goto bail3;
1412                 }
1413
1414                 /*
1415                  * Everything seems to be there, now take a closer look at what
1416                  * is in each header
1417                  */
1418
1419                 strtolower(wsi->utf8_token[WSI_TOKEN_HTTP].token);
1420                 if (strcmp(wsi->utf8_token[WSI_TOKEN_HTTP].token,
1421                                                    "101 switching protocols")) {
1422                         fprintf(stderr, "libwebsocket_client_handshake "
1423                                         "server sent bad HTTP response '%s'\n",
1424                                          wsi->utf8_token[WSI_TOKEN_HTTP].token);
1425                         goto bail3;
1426                 }
1427
1428                 strtolower(wsi->utf8_token[WSI_TOKEN_UPGRADE].token);
1429                 if (strcmp(wsi->utf8_token[WSI_TOKEN_UPGRADE].token,
1430                                                                  "websocket")) {
1431                         fprintf(stderr, "libwebsocket_client_handshake server "
1432                                         "sent bad Upgrade header '%s'\n",
1433                                       wsi->utf8_token[WSI_TOKEN_UPGRADE].token);
1434                         goto bail3;
1435                 }
1436
1437                 strtolower(wsi->utf8_token[WSI_TOKEN_CONNECTION].token);
1438                 if (strcmp(wsi->utf8_token[WSI_TOKEN_CONNECTION].token,
1439                                                                    "upgrade")) {
1440                         fprintf(stderr, "libwebsocket_client_handshake server "
1441                                         "sent bad Connection hdr '%s'\n",
1442                                    wsi->utf8_token[WSI_TOKEN_CONNECTION].token);
1443                         goto bail3;
1444                 }
1445
1446 select_protocol:
1447                 pc = wsi->c_protocol;
1448
1449                 /*
1450                  * confirm the protocol the server wants to talk was in the list
1451                  * of protocols we offered
1452                  */
1453
1454                 if (!wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len) {
1455
1456                         /*
1457                          * no protocol name to work from,
1458                          * default to first protocol
1459                          */
1460                         wsi->protocol = &context->protocols[0];
1461
1462                         free(wsi->c_protocol);
1463
1464                         goto check_accept;
1465                 }
1466
1467                 while (*pc && !okay) {
1468                         if ((!strncmp(pc,
1469                                 wsi->utf8_token[WSI_TOKEN_PROTOCOL].token,
1470                            wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len)) &&
1471                  (pc[wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len] == ',' ||
1472                    pc[wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len] == '\0')) {
1473                                 okay = 1;
1474                                 continue;
1475                         }
1476                         while (*pc && *pc != ',')
1477                                 pc++;
1478                         while (*pc && *pc != ' ')
1479                                 pc++;
1480                 }
1481
1482                 /* done with him now */
1483
1484                 if (wsi->c_protocol)
1485                         free(wsi->c_protocol);
1486
1487
1488                 if (!okay) {
1489                         fprintf(stderr, "libwebsocket_client_handshake server "
1490                                                 "sent bad protocol '%s'\n",
1491                                      wsi->utf8_token[WSI_TOKEN_PROTOCOL].token);
1492                         goto bail2;
1493                 }
1494
1495                 /*
1496                  * identify the selected protocol struct and set it
1497                  */
1498                 n = 0;
1499                 wsi->protocol = NULL;
1500                 while (context->protocols[n].callback) {
1501                         if (strcmp(wsi->utf8_token[WSI_TOKEN_PROTOCOL].token,
1502                                                context->protocols[n].name) == 0)
1503                                 wsi->protocol = &context->protocols[n];
1504                         n++;
1505                 }
1506
1507                 if (wsi->protocol == NULL) {
1508                         fprintf(stderr, "libwebsocket_client_handshake server "
1509                                         "requested protocol '%s', which we "
1510                                         "said we supported but we don't!\n",
1511                                      wsi->utf8_token[WSI_TOKEN_PROTOCOL].token);
1512                         goto bail2;
1513                 }
1514
1515
1516                 /* instantiate the accepted extensions */
1517
1518                 if (!wsi->utf8_token[WSI_TOKEN_EXTENSIONS].token_len)
1519                         goto check_accept;
1520
1521                 /*
1522                  * break down the list of server accepted extensions
1523                  * and go through matching them or identifying bogons
1524                  */
1525
1526                 c = wsi->utf8_token[WSI_TOKEN_EXTENSIONS].token;
1527                 n = 0;
1528                 while (more) {
1529
1530                         if (*c && *c != ',') {
1531                                 ext_name[n] = *c++;
1532                                 if (n < sizeof(ext_name) - 1)
1533                                         n++;
1534                                 continue;
1535                         }
1536                         ext_name[n] = '\0';
1537                         if (!*c)
1538                                 more = 0;
1539
1540                         /* check we actually support it */
1541
1542                         n = 0;
1543                         ext = wsi->protocol->owning_server->extensions;
1544                         while (ext && ext->callback) {
1545
1546                                 if (strcmp(ext_name, ext->name)) {
1547                                         ext++;
1548                                         continue;
1549                                 }
1550
1551                                 n = 1;
1552
1553                                 /* instantiate the extension on this conn */
1554
1555                                 wsi->active_extensions_user[
1556                                         wsi->count_active_extensions] =
1557                                              malloc(ext->per_session_data_size);
1558                                 wsi->active_extensions[
1559                                           wsi->count_active_extensions] = ext;
1560
1561                                 /* allow him to construct his context */
1562
1563                                 ext->callback(wsi->protocol->owning_server,
1564                                         wsi, LWS_EXT_CALLBACK_CLIENT_CONSTRUCT,
1565                                                 wsi->active_extensions_user[
1566                                         wsi->count_active_extensions], NULL, 0);
1567
1568                                 wsi->count_active_extensions++;
1569
1570                                 ext++;
1571                         }
1572
1573                         if (n == 0) {
1574                                 fprintf(stderr, "Server said we should use"
1575                                       "an unknown extension '%s'!\n", ext_name);
1576                                 goto bail2;
1577                         }
1578
1579                         n = 0;
1580                 }
1581
1582
1583         check_accept:
1584
1585                 if (wsi->ietf_spec_revision == 0) {
1586
1587                         if (memcmp(wsi->initial_handshake_hash_base64,
1588                               wsi->utf8_token[WSI_TOKEN_CHALLENGE].token, 16)) {
1589                                 fprintf(stderr, "libwebsocket_client_handshake "
1590                                                "failed 00 challenge compare\n");
1591                                         pkt[len] = '\0';
1592                                         fprintf(stderr, "%s", pkt);
1593                                         goto bail2;
1594                         }
1595
1596                         goto accept_ok;
1597                 }
1598
1599                 /*
1600                  * Confirm his accept token is the one we precomputed
1601                  */
1602
1603                 if (strcmp(wsi->utf8_token[WSI_TOKEN_ACCEPT].token,
1604                                           wsi->initial_handshake_hash_base64)) {
1605                         fprintf(stderr, "libwebsocket_client_handshake server "
1606                                 "sent bad ACCEPT '%s' vs computed '%s'\n",
1607                                 wsi->utf8_token[WSI_TOKEN_ACCEPT].token,
1608                                             wsi->initial_handshake_hash_base64);
1609                         goto bail2;
1610                 }
1611
1612                 if (wsi->ietf_spec_revision == 4) {
1613                         /*
1614                          * Calculate the 04 masking key to use when
1615                          * sending data to server
1616                          */
1617
1618                         strcpy((char *)buf, wsi->key_b64);
1619                         p = (char *)buf + strlen(wsi->key_b64);
1620                         strcpy(p, wsi->utf8_token[WSI_TOKEN_NONCE].token);
1621                         p += wsi->utf8_token[WSI_TOKEN_NONCE].token_len;
1622                         strcpy(p, magic_websocket_04_masking_guid);
1623                         SHA1(buf, strlen((char *)buf), wsi->masking_key_04);
1624                 }
1625 accept_ok:
1626
1627                 /* allocate the per-connection user memory (if any) */
1628
1629                 if (wsi->protocol->per_session_data_size) {
1630                         wsi->user_space = malloc(
1631                                           wsi->protocol->per_session_data_size);
1632                         if (wsi->user_space  == NULL) {
1633                                 fprintf(stderr, "Out of memory for "
1634                                                            "conn user space\n");
1635                                 goto bail2;
1636                         }
1637                 } else
1638                         wsi->user_space = NULL;
1639
1640                 /* clear his proxy connection timeout */
1641
1642                 libwebsocket_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
1643
1644                 /* mark him as being alive */
1645
1646                 wsi->state = WSI_STATE_ESTABLISHED;
1647                 wsi->mode = LWS_CONNMODE_WS_CLIENT;
1648
1649                 fprintf(stderr, "handshake OK for protocol %s\n",
1650                                                            wsi->protocol->name);
1651
1652                 /* call him back to inform him he is up */
1653
1654                 wsi->protocol->callback(context, wsi,
1655                                  LWS_CALLBACK_CLIENT_ESTABLISHED,
1656                                  wsi->user_space,
1657                                  NULL, 0);
1658
1659                 break;
1660
1661 bail3:
1662                 if (wsi->c_protocol)
1663                         free(wsi->c_protocol);
1664
1665 bail2:
1666                 libwebsocket_close_and_free_session(context, wsi,
1667                                                      LWS_CLOSE_STATUS_NOSTATUS);
1668                 return 1;
1669
1670
1671         case LWS_CONNMODE_WS_SERVING:
1672         case LWS_CONNMODE_WS_CLIENT:
1673
1674                 /* handle session socket closed */
1675
1676                 if (pollfd->revents & (POLLERR | POLLHUP)) {
1677
1678                         fprintf(stderr, "Session Socket %p (fd=%d) dead\n",
1679                                 (void *)wsi, pollfd->fd);
1680
1681                         libwebsocket_close_and_free_session(context, wsi,
1682                                                      LWS_CLOSE_STATUS_NOSTATUS);
1683                         return 1;
1684                 }
1685
1686                 /* the guy requested a callback when it was OK to write */
1687
1688                 if ((pollfd->revents & POLLOUT) &&
1689                                             wsi->state == WSI_STATE_ESTABLISHED)
1690                         if (lws_handle_POLLOUT_event(context, wsi,
1691                                                                   pollfd) < 0) {
1692                                 libwebsocket_close_and_free_session(
1693                                          context, wsi, LWS_CLOSE_STATUS_NORMAL);
1694                                 return 1;
1695                         }
1696
1697
1698                 /* any incoming data ready? */
1699
1700                 if (!(pollfd->revents & POLLIN))
1701                         break;
1702
1703 #ifdef LWS_OPENSSL_SUPPORT
1704                 if (wsi->ssl)
1705                         eff_buf.token_len = SSL_read(wsi->ssl, buf, sizeof buf);
1706                 else
1707 #endif
1708                         eff_buf.token_len =
1709                                            recv(pollfd->fd, buf, sizeof buf, 0);
1710
1711                 if (eff_buf.token_len < 0) {
1712                         fprintf(stderr, "Socket read returned %d\n",
1713                                                             eff_buf.token_len);
1714                         break;
1715                 }
1716                 if (!eff_buf.token_len) {
1717                         libwebsocket_close_and_free_session(context, wsi,
1718                                                      LWS_CLOSE_STATUS_NOSTATUS);
1719                         return 1;
1720                 }
1721
1722                 /*
1723                  * give any active extensions a chance to munge the buffer
1724                  * before parse.  We pass in a pointer to an lws_tokens struct
1725                  * prepared with the default buffer and content length that's in
1726                  * there.  Rather than rewrite the default buffer, extensions
1727                  * that expect to grow the buffer can adapt .token to
1728                  * point to their own per-connection buffer in the extension
1729                  * user allocation.  By default with no extensions or no
1730                  * extension callback handling, just the normal input buffer is
1731                  * used then so it is efficient.
1732                  */
1733
1734                 eff_buf.token = (char *)buf;
1735
1736                 more = 1;
1737                 while (more) {
1738
1739                         more = 0;
1740
1741                         for (n = 0; n < wsi->count_active_extensions; n++) {
1742                                 m = wsi->active_extensions[n]->callback(context, wsi,
1743                                         LWS_EXT_CALLBACK_PACKET_RX_PREPARSE,
1744                                      wsi->active_extensions_user[n], &eff_buf, 0);
1745                                 if (m < 0) {
1746                                         fprintf(stderr, "Extension reports fatal error\n");
1747                                         libwebsocket_close_and_free_session(context, wsi,
1748                                                              LWS_CLOSE_STATUS_NOSTATUS);
1749                                         return 1;
1750                                 }
1751                                 if (m)
1752                                         more = 1;
1753                         }
1754
1755                         /* service incoming data */
1756
1757                         if (eff_buf.token_len) {
1758                                 n = libwebsocket_read(context, wsi,
1759                                      (unsigned char *)eff_buf.token, eff_buf.token_len);
1760                                 if (n < 0)
1761                                         /* we closed wsi */
1762                                         return 1;
1763                         }
1764
1765                         eff_buf.token = NULL;
1766                         eff_buf.token_len = 0;
1767                 }
1768                 break;
1769         }
1770
1771         return 0;
1772 }
1773
1774
1775 /**
1776  * libwebsocket_context_destroy() - Destroy the websocket context
1777  * @context:    Websocket context
1778  *
1779  *      This function closes any active connections and then frees the
1780  *      context.  After calling this, any further use of the context is
1781  *      undefined.
1782  */
1783 void
1784 libwebsocket_context_destroy(struct libwebsocket_context *context)
1785 {
1786         int n;
1787         int m;
1788         struct libwebsocket *wsi;
1789
1790         for (n = 0; n < FD_HASHTABLE_MODULUS; n++)
1791                 for (m = 0; m < context->fd_hashtable[n].length; m++) {
1792                         wsi = context->fd_hashtable[n].wsi[m];
1793                         libwebsocket_close_and_free_session(context, wsi,
1794                                                     LWS_CLOSE_STATUS_GOINGAWAY);
1795                 }
1796
1797 #ifdef WIN32
1798 #else
1799         close(context->fd_random);
1800 #endif
1801
1802 #ifdef LWS_OPENSSL_SUPPORT
1803         if (context->ssl_ctx)
1804                 SSL_CTX_free(context->ssl_ctx);
1805         if (context->ssl_client_ctx)
1806                 SSL_CTX_free(context->ssl_client_ctx);
1807 #endif
1808
1809         free(context);
1810
1811 #ifdef WIN32
1812         WSACleanup();
1813 #endif
1814 }
1815
1816 /**
1817  * libwebsocket_service() - Service any pending websocket activity
1818  * @context:    Websocket context
1819  * @timeout_ms: Timeout for poll; 0 means return immediately if nothing needed
1820  *              service otherwise block and service immediately, returning
1821  *              after the timeout if nothing needed service.
1822  *
1823  *      This function deals with any pending websocket traffic, for three
1824  *      kinds of event.  It handles these events on both server and client
1825  *      types of connection the same.
1826  *
1827  *      1) Accept new connections to our context's server
1828  *
1829  *      2) Perform pending broadcast writes initiated from other forked
1830  *         processes (effectively serializing asynchronous broadcasts)
1831  *
1832  *      3) Call the receive callback for incoming frame data received by
1833  *          server or client connections.
1834  *
1835  *      You need to call this service function periodically to all the above
1836  *      functions to happen; if your application is single-threaded you can
1837  *      just call it in your main event loop.
1838  *
1839  *      Alternatively you can fork a new process that asynchronously handles
1840  *      calling this service in a loop.  In that case you are happy if this
1841  *      call blocks your thread until it needs to take care of something and
1842  *      would call it with a large nonzero timeout.  Your loop then takes no
1843  *      CPU while there is nothing happening.
1844  *
1845  *      If you are calling it in a single-threaded app, you don't want it to
1846  *      wait around blocking other things in your loop from happening, so you
1847  *      would call it with a timeout_ms of 0, so it returns immediately if
1848  *      nothing is pending, or as soon as it services whatever was pending.
1849  */
1850
1851
1852 int
1853 libwebsocket_service(struct libwebsocket_context *context, int timeout_ms)
1854 {
1855         int n;
1856
1857         /* stay dead once we are dead */
1858
1859         if (context == NULL)
1860                 return 1;
1861
1862         /* wait for something to need service */
1863
1864         n = poll(context->fds, context->fds_count, timeout_ms);
1865         if (n == 0) /* poll timeout */
1866                 return 0;
1867
1868         if (n < 0) {
1869                 /*
1870                 fprintf(stderr, "Listen Socket dead\n");
1871                 */
1872                 return 1;
1873         }
1874
1875         /* handle accept on listening socket? */
1876
1877         for (n = 0; n < context->fds_count; n++)
1878                 if (context->fds[n].revents)
1879                         libwebsocket_service_fd(context, &context->fds[n]);
1880
1881         return 0;
1882 }
1883
1884 /**
1885  * libwebsocket_callback_on_writable() - Request a callback when this socket
1886  *                                       becomes able to be written to without
1887  *                                       blocking
1888  *
1889  * @context:    libwebsockets context
1890  * @wsi:        Websocket connection instance to get callback for
1891  */
1892
1893 int
1894 libwebsocket_callback_on_writable(struct libwebsocket_context *context,
1895                                                        struct libwebsocket *wsi)
1896 {
1897         int n;
1898
1899         for (n = 0; n < context->fds_count; n++)
1900                 if (context->fds[n].fd == wsi->sock) {
1901                         context->fds[n].events |= POLLOUT;
1902                         n = context->fds_count;
1903                 }
1904
1905         /* external POLL support via protocol 0 */
1906         context->protocols[0].callback(context, wsi,
1907                 LWS_CALLBACK_SET_MODE_POLL_FD,
1908                 (void *)(long)wsi->sock, NULL, POLLOUT);
1909
1910         return 1;
1911 }
1912
1913 /**
1914  * libwebsocket_callback_on_writable_all_protocol() - Request a callback for
1915  *                      all connections using the given protocol when it
1916  *                      becomes possible to write to each socket without
1917  *                      blocking in turn.
1918  *
1919  * @protocol:   Protocol whose connections will get callbacks
1920  */
1921
1922 int
1923 libwebsocket_callback_on_writable_all_protocol(
1924                                   const struct libwebsocket_protocols *protocol)
1925 {
1926         struct libwebsocket_context *context = protocol->owning_server;
1927         int n;
1928         int m;
1929         struct libwebsocket *wsi;
1930
1931         for (n = 0; n < FD_HASHTABLE_MODULUS; n++) {
1932
1933                 for (m = 0; m < context->fd_hashtable[n].length; m++) {
1934
1935                         wsi = context->fd_hashtable[n].wsi[m];
1936
1937                         if (wsi->protocol == protocol)
1938                                 libwebsocket_callback_on_writable(context, wsi);
1939                 }
1940         }
1941
1942         return 0;
1943 }
1944
1945 /**
1946  * libwebsocket_set_timeout() - marks the wsi as subject to a timeout
1947  *
1948  * You will not need this unless you are doing something special
1949  *
1950  * @wsi:        Websocket connection instance
1951  * @reason:     timeout reason
1952  * @secs:       how many seconds
1953  */
1954
1955 void
1956 libwebsocket_set_timeout(struct libwebsocket *wsi,
1957                                           enum pending_timeout reason, int secs)
1958 {
1959         struct timeval tv;
1960
1961         gettimeofday(&tv, NULL);
1962
1963         wsi->pending_timeout_limit = tv.tv_sec + secs;
1964         wsi->pending_timeout = reason;
1965 }
1966
1967
1968 /**
1969  * libwebsocket_get_socket_fd() - returns the socket file descriptor
1970  *
1971  * You will not need this unless you are doing something special
1972  *
1973  * @wsi:        Websocket connection instance
1974  */
1975
1976 int
1977 libwebsocket_get_socket_fd(struct libwebsocket *wsi)
1978 {
1979         return wsi->sock;
1980 }
1981
1982 /**
1983  * libwebsocket_rx_flow_control() - Enable and disable socket servicing for
1984  *                              receieved packets.
1985  *
1986  * If the output side of a server process becomes choked, this allows flow
1987  * control for the input side.
1988  *
1989  * @wsi:        Websocket connection instance to get callback for
1990  * @enable:     0 = disable read servicing for this connection, 1 = enable
1991  */
1992
1993 int
1994 libwebsocket_rx_flow_control(struct libwebsocket *wsi, int enable)
1995 {
1996         struct libwebsocket_context *context = wsi->protocol->owning_server;
1997         int n;
1998
1999         for (n = 0; n < context->fds_count; n++)
2000                 if (context->fds[n].fd == wsi->sock) {
2001                         if (enable)
2002                                 context->fds[n].events |= POLLIN;
2003                         else
2004                                 context->fds[n].events &= ~POLLIN;
2005
2006                         return 0;
2007                 }
2008
2009         if (enable)
2010                 /* external POLL support via protocol 0 */
2011                 context->protocols[0].callback(context, wsi,
2012                         LWS_CALLBACK_SET_MODE_POLL_FD,
2013                         (void *)(long)wsi->sock, NULL, POLLIN);
2014         else
2015                 /* external POLL support via protocol 0 */
2016                 context->protocols[0].callback(context, wsi,
2017                         LWS_CALLBACK_CLEAR_MODE_POLL_FD,
2018                         (void *)(long)wsi->sock, NULL, POLLIN);
2019
2020
2021         fprintf(stderr, "libwebsocket_callback_on_writable "
2022                                                      "unable to find socket\n");
2023         return 1;
2024 }
2025
2026 /**
2027  * libwebsocket_canonical_hostname() - returns this host's hostname
2028  *
2029  * This is typically used by client code to fill in the host parameter
2030  * when making a client connection.  You can only call it after the context
2031  * has been created.
2032  *
2033  * @context:    Websocket context
2034  */
2035
2036
2037 extern const char *
2038 libwebsocket_canonical_hostname(struct libwebsocket_context *context)
2039 {
2040         return (const char *)context->canonical_hostname;
2041 }
2042
2043
2044 static void sigpipe_handler(int x)
2045 {
2046 }
2047
2048 #ifdef LWS_OPENSSL_SUPPORT
2049 static int
2050 OpenSSL_verify_callback(int preverify_ok, X509_STORE_CTX *x509_ctx)
2051 {
2052
2053         SSL *ssl;
2054         int n;
2055         struct libwebsocket_context *context;
2056
2057         ssl = X509_STORE_CTX_get_ex_data(x509_ctx,
2058                 SSL_get_ex_data_X509_STORE_CTX_idx());
2059
2060         /*
2061          * !!! nasty openssl requires the index to come as a library-scope
2062          * static
2063          */
2064         context = SSL_get_ex_data(ssl, openssl_websocket_private_data_index);
2065
2066         n = context->protocols[0].callback(NULL, NULL,
2067                 LWS_CALLBACK_OPENSSL_PERFORM_CLIENT_CERT_VERIFICATION,
2068                                                    x509_ctx, ssl, preverify_ok);
2069
2070         /* convert return code from 0 = OK to 1 = OK */
2071
2072         if (!n)
2073                 n = 1;
2074         else
2075                 n = 0;
2076
2077         return n;
2078 }
2079 #endif
2080
2081
2082 /**
2083  * libwebsocket_create_context() - Create the websocket handler
2084  * @port:       Port to listen on... you can use 0 to suppress listening on
2085  *              any port, that's what you want if you are not running a
2086  *              websocket server at all but just using it as a client
2087  * @interf:  NULL to bind the listen socket to all interfaces, or the
2088  *              interface name, eg, "eth2"
2089  * @protocols:  Array of structures listing supported protocols and a protocol-
2090  *              specific callback for each one.  The list is ended with an
2091  *              entry that has a NULL callback pointer.
2092  *              It's not const because we write the owning_server member
2093  * @extensions: NULL or array of libwebsocket_extension structs listing the
2094  *              extensions this context supports
2095  * @ssl_cert_filepath:  If libwebsockets was compiled to use ssl, and you want
2096  *                      to listen using SSL, set to the filepath to fetch the
2097  *                      server cert from, otherwise NULL for unencrypted
2098  * @ssl_private_key_filepath: filepath to private key if wanting SSL mode,
2099  *                      else ignored
2100  * @gid:        group id to change to after setting listen socket, or -1.
2101  * @uid:        user id to change to after setting listen socket, or -1.
2102  * @options:    0, or LWS_SERVER_OPTION_DEFEAT_CLIENT_MASK
2103  *
2104  *      This function creates the listening socket and takes care
2105  *      of all initialization in one step.
2106  *
2107  *      After initialization, it returns a struct libwebsocket_context * that
2108  *      represents this server.  After calling, user code needs to take care
2109  *      of calling libwebsocket_service() with the context pointer to get the
2110  *      server's sockets serviced.  This can be done in the same process context
2111  *      or a forked process, or another thread,
2112  *
2113  *      The protocol callback functions are called for a handful of events
2114  *      including http requests coming in, websocket connections becoming
2115  *      established, and data arriving; it's also called periodically to allow
2116  *      async transmission.
2117  *
2118  *      HTTP requests are sent always to the FIRST protocol in @protocol, since
2119  *      at that time websocket protocol has not been negotiated.  Other
2120  *      protocols after the first one never see any HTTP callack activity.
2121  *
2122  *      The server created is a simple http server by default; part of the
2123  *      websocket standard is upgrading this http connection to a websocket one.
2124  *
2125  *      This allows the same server to provide files like scripts and favicon /
2126  *      images or whatever over http and dynamic data over websockets all in
2127  *      one place; they're all handled in the user callback.
2128  */
2129
2130 struct libwebsocket_context *
2131 libwebsocket_create_context(int port, const char *interf,
2132                                struct libwebsocket_protocols *protocols,
2133                                struct libwebsocket_extension *extensions,
2134                                const char *ssl_cert_filepath,
2135                                const char *ssl_private_key_filepath,
2136                                int gid, int uid, unsigned int options)
2137 {
2138         int n;
2139         int sockfd = 0;
2140         int fd;
2141         struct sockaddr_in serv_addr, cli_addr;
2142         int opt = 1;
2143         struct libwebsocket_context *context = NULL;
2144         unsigned int slen;
2145         char *p;
2146         char hostname[1024];
2147         struct hostent *he;
2148         struct libwebsocket *wsi;
2149
2150 #ifdef LWS_OPENSSL_SUPPORT
2151         SSL_METHOD *method;
2152         char ssl_err_buf[512];
2153 #endif
2154
2155 #ifdef _WIN32
2156         {
2157                 WORD wVersionRequested;
2158                 WSADATA wsaData;
2159                 int err;
2160
2161                 /* Use the MAKEWORD(lowbyte, highbyte) macro from Windef.h */
2162                 wVersionRequested = MAKEWORD(2, 2);
2163
2164                 err = WSAStartup(wVersionRequested, &wsaData);
2165                 if (err != 0) {
2166                         /* Tell the user that we could not find a usable */
2167                         /* Winsock DLL.                                  */
2168                         fprintf(stderr, "WSAStartup failed with error: %d\n",
2169                                                                            err);
2170                         return NULL;
2171                 }
2172         }
2173 #endif
2174
2175
2176         context = malloc(sizeof(struct libwebsocket_context));
2177         if (!context) {
2178                 fprintf(stderr, "No memory for websocket context\n");
2179                 return NULL;
2180         }
2181         context->protocols = protocols;
2182         context->listen_port = port;
2183         context->http_proxy_port = 0;
2184         context->http_proxy_address[0] = '\0';
2185         context->options = options;
2186         context->fds_count = 0;
2187         context->extensions = extensions;
2188
2189 #ifdef WIN32
2190         context->fd_random = 0;
2191 #else
2192         context->fd_random = open(SYSTEM_RANDOM_FILEPATH, O_RDONLY);
2193         if (context->fd_random < 0) {
2194                 fprintf(stderr, "Unable to open random device %s %d\n",
2195                                     SYSTEM_RANDOM_FILEPATH, context->fd_random);
2196                 return NULL;
2197         }
2198 #endif
2199
2200 #ifdef LWS_OPENSSL_SUPPORT
2201         context->use_ssl = 0;
2202         context->ssl_ctx = NULL;
2203         context->ssl_client_ctx = NULL;
2204         openssl_websocket_private_data_index = 0;
2205 #endif
2206         /* find canonical hostname */
2207
2208         hostname[(sizeof hostname) - 1] = '\0';
2209         gethostname(hostname, (sizeof hostname) - 1);
2210         he = gethostbyname(hostname);
2211         if (he) {
2212                 strncpy(context->canonical_hostname, he->h_name,
2213                                         sizeof context->canonical_hostname - 1);
2214                 context->canonical_hostname[
2215                                 sizeof context->canonical_hostname - 1] = '\0';
2216         } else
2217                 strncpy(context->canonical_hostname, hostname,
2218                                         sizeof context->canonical_hostname - 1);
2219
2220         /* split the proxy ads:port if given */
2221
2222         p = getenv("http_proxy");
2223         if (p) {
2224                 strncpy(context->http_proxy_address, p,
2225                                         sizeof context->http_proxy_address - 1);
2226                 context->http_proxy_address[
2227                                  sizeof context->http_proxy_address - 1] = '\0';
2228
2229                 p = strchr(context->http_proxy_address, ':');
2230                 if (p == NULL) {
2231                         fprintf(stderr, "http_proxy needs to be ads:port\n");
2232                         return NULL;
2233                 }
2234                 *p = '\0';
2235                 context->http_proxy_port = atoi(p + 1);
2236
2237                 fprintf(stderr, "Using proxy %s:%u\n",
2238                                 context->http_proxy_address,
2239                                                       context->http_proxy_port);
2240         }
2241
2242         if (port) {
2243
2244 #ifdef LWS_OPENSSL_SUPPORT
2245                 context->use_ssl = ssl_cert_filepath != NULL &&
2246                                                ssl_private_key_filepath != NULL;
2247                 if (context->use_ssl)
2248                         fprintf(stderr, " Compiled with SSL support, "
2249                                                                   "using it\n");
2250                 else
2251                         fprintf(stderr, " Compiled with SSL support, "
2252                                                               "not using it\n");
2253
2254 #else
2255                 if (ssl_cert_filepath != NULL &&
2256                                              ssl_private_key_filepath != NULL) {
2257                         fprintf(stderr, " Not compiled for OpenSSl support!\n");
2258                         return NULL;
2259                 }
2260                 fprintf(stderr, " Compiled without SSL support, "
2261                                                        "serving unencrypted\n");
2262 #endif
2263         }
2264
2265         /* ignore SIGPIPE */
2266 #ifdef WIN32
2267 #else
2268         signal(SIGPIPE, sigpipe_handler);
2269 #endif
2270
2271
2272 #ifdef LWS_OPENSSL_SUPPORT
2273
2274         /* basic openssl init */
2275
2276         SSL_library_init();
2277
2278         OpenSSL_add_all_algorithms();
2279         SSL_load_error_strings();
2280
2281         openssl_websocket_private_data_index =
2282                 SSL_get_ex_new_index(0, "libwebsockets", NULL, NULL, NULL);
2283
2284         /*
2285          * Firefox insists on SSLv23 not SSLv3
2286          * Konq disables SSLv2 by default now, SSLv23 works
2287          */
2288
2289         method = (SSL_METHOD *)SSLv23_server_method();
2290         if (!method) {
2291                 fprintf(stderr, "problem creating ssl method: %s\n",
2292                         ERR_error_string(ERR_get_error(), ssl_err_buf));
2293                 return NULL;
2294         }
2295         context->ssl_ctx = SSL_CTX_new(method); /* create context */
2296         if (!context->ssl_ctx) {
2297                 fprintf(stderr, "problem creating ssl context: %s\n",
2298                         ERR_error_string(ERR_get_error(), ssl_err_buf));
2299                 return NULL;
2300         }
2301
2302         /* client context */
2303         if (port == CONTEXT_PORT_NO_LISTEN)
2304         {
2305                 method = (SSL_METHOD *)SSLv23_client_method();
2306                 if (!method) {
2307                         fprintf(stderr, "problem creating ssl method: %s\n",
2308                                 ERR_error_string(ERR_get_error(), ssl_err_buf));
2309                         return NULL;
2310                 }
2311                 /* create context */
2312                 context->ssl_client_ctx = SSL_CTX_new(method);
2313                 if (!context->ssl_client_ctx) {
2314                         fprintf(stderr, "problem creating ssl context: %s\n",
2315                                 ERR_error_string(ERR_get_error(), ssl_err_buf));
2316                         return NULL;
2317                 }
2318
2319                 /* openssl init for cert verification (for client sockets) */
2320
2321                 if (!SSL_CTX_load_verify_locations(
2322                                         context->ssl_client_ctx, NULL,
2323                                                       LWS_OPENSSL_CLIENT_CERTS))
2324                         fprintf(stderr,
2325                             "Unable to load SSL Client certs from %s "
2326                             "(set by --with-client-cert-dir= in configure) -- "
2327                                 " client ssl isn't going to work",
2328                                                       LWS_OPENSSL_CLIENT_CERTS);
2329
2330                 /*
2331                  * callback allowing user code to load extra verification certs
2332                  * helping the client to verify server identity
2333                  */
2334
2335                 context->protocols[0].callback(context, NULL,
2336                         LWS_CALLBACK_OPENSSL_LOAD_EXTRA_CLIENT_VERIFY_CERTS,
2337                         context->ssl_client_ctx, NULL, 0);
2338         }
2339         /* as a server, are we requiring clients to identify themselves? */
2340
2341         if (options & LWS_SERVER_OPTION_REQUIRE_VALID_OPENSSL_CLIENT_CERT) {
2342
2343                 /* absolutely require the client cert */
2344
2345                 SSL_CTX_set_verify(context->ssl_ctx,
2346                        SSL_VERIFY_PEER | SSL_VERIFY_FAIL_IF_NO_PEER_CERT,
2347                                                        OpenSSL_verify_callback);
2348
2349                 /*
2350                  * give user code a chance to load certs into the server
2351                  * allowing it to verify incoming client certs
2352                  */
2353
2354                 context->protocols[0].callback(context, NULL,
2355                         LWS_CALLBACK_OPENSSL_LOAD_EXTRA_SERVER_VERIFY_CERTS,
2356                                                      context->ssl_ctx, NULL, 0);
2357         }
2358
2359         if (context->use_ssl) {
2360
2361                 /* openssl init for server sockets */
2362
2363                 /* set the local certificate from CertFile */
2364                 n = SSL_CTX_use_certificate_file(context->ssl_ctx,
2365                                         ssl_cert_filepath, SSL_FILETYPE_PEM);
2366                 if (n != 1) {
2367                         fprintf(stderr, "problem getting cert '%s': %s\n",
2368                                 ssl_cert_filepath,
2369                                 ERR_error_string(ERR_get_error(), ssl_err_buf));
2370                         return NULL;
2371                 }
2372                 /* set the private key from KeyFile */
2373                 if (SSL_CTX_use_PrivateKey_file(context->ssl_ctx,
2374                              ssl_private_key_filepath, SSL_FILETYPE_PEM) != 1) {
2375                         fprintf(stderr, "ssl problem getting key '%s': %s\n",
2376                                                 ssl_private_key_filepath,
2377                                 ERR_error_string(ERR_get_error(), ssl_err_buf));
2378                         return NULL;
2379                 }
2380                 /* verify private key */
2381                 if (!SSL_CTX_check_private_key(context->ssl_ctx)) {
2382                         fprintf(stderr, "Private SSL key doesn't match cert\n");
2383                         return NULL;
2384                 }
2385
2386                 /* SSL is happy and has a cert it's content with */
2387         }
2388 #endif
2389
2390         /* selftest */
2391
2392         if (lws_b64_selftest())
2393                 return NULL;
2394
2395         /* fd hashtable init */
2396
2397         for (n = 0; n < FD_HASHTABLE_MODULUS; n++)
2398                 context->fd_hashtable[n].length = 0;
2399
2400         /* set up our external listening socket we serve on */
2401
2402         if (port) {
2403
2404                 sockfd = socket(AF_INET, SOCK_STREAM, 0);
2405                 if (sockfd < 0) {
2406                         fprintf(stderr, "ERROR opening socket");
2407                         return NULL;
2408                 }
2409
2410                 /* allow us to restart even if old sockets in TIME_WAIT */
2411                 setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt));
2412
2413                 bzero((char *) &serv_addr, sizeof(serv_addr));
2414                 serv_addr.sin_family = AF_INET;
2415                 if (interf == NULL)
2416                         serv_addr.sin_addr.s_addr = INADDR_ANY;
2417                 else
2418                         interface_to_sa(interf, &serv_addr,
2419                                                 sizeof(serv_addr));
2420                 serv_addr.sin_port = htons(port);
2421
2422                 n = bind(sockfd, (struct sockaddr *) &serv_addr,
2423                                                              sizeof(serv_addr));
2424                 if (n < 0) {
2425                         fprintf(stderr, "ERROR on binding to port %d (%d %d)\n",
2426                                                                 port, n, errno);
2427                         return NULL;
2428                 }
2429
2430                 wsi = malloc(sizeof(struct libwebsocket));
2431                 memset(wsi, 0, sizeof (struct libwebsocket));
2432                 wsi->sock = sockfd;
2433                 wsi->count_active_extensions = 0;
2434                 wsi->mode = LWS_CONNMODE_SERVER_LISTENER;
2435                 insert_wsi(context, wsi);
2436
2437                 listen(sockfd, 5);
2438                 fprintf(stderr, " Listening on port %d\n", port);
2439
2440                 /* list in the internal poll array */
2441
2442                 context->fds[context->fds_count].fd = sockfd;
2443                 context->fds[context->fds_count++].events = POLLIN;
2444
2445                 /* external POLL support via protocol 0 */
2446                 context->protocols[0].callback(context, wsi,
2447                         LWS_CALLBACK_ADD_POLL_FD,
2448                         (void *)(long)sockfd, NULL, POLLIN);
2449
2450         }
2451
2452         /* drop any root privs for this process */
2453 #ifdef WIN32
2454 #else
2455         if (gid != -1)
2456                 if (setgid(gid))
2457                         fprintf(stderr, "setgid: %s\n", strerror(errno));
2458         if (uid != -1)
2459                 if (setuid(uid))
2460                         fprintf(stderr, "setuid: %s\n", strerror(errno));
2461 #endif
2462
2463         /* set up our internal broadcast trigger sockets per-protocol */
2464
2465         for (context->count_protocols = 0;
2466                         protocols[context->count_protocols].callback;
2467                                                    context->count_protocols++) {
2468                 protocols[context->count_protocols].owning_server = context;
2469                 protocols[context->count_protocols].protocol_index =
2470                                                        context->count_protocols;
2471
2472                 fd = socket(AF_INET, SOCK_STREAM, 0);
2473                 if (fd < 0) {
2474                         fprintf(stderr, "ERROR opening socket");
2475                         return NULL;
2476                 }
2477
2478                 /* allow us to restart even if old sockets in TIME_WAIT */
2479                 setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt));
2480
2481                 bzero((char *) &serv_addr, sizeof(serv_addr));
2482                 serv_addr.sin_family = AF_INET;
2483                 serv_addr.sin_addr.s_addr = inet_addr("127.0.0.1");
2484                 serv_addr.sin_port = 0; /* pick the port for us */
2485
2486                 n = bind(fd, (struct sockaddr *) &serv_addr, sizeof(serv_addr));
2487                 if (n < 0) {
2488                         fprintf(stderr, "ERROR on binding to port %d (%d %d)\n",
2489                                                                 port, n, errno);
2490                         return NULL;
2491                 }
2492
2493                 slen = sizeof cli_addr;
2494                 n = getsockname(fd, (struct sockaddr *)&cli_addr, &slen);
2495                 if (n < 0) {
2496                         fprintf(stderr, "getsockname failed\n");
2497                         return NULL;
2498                 }
2499                 protocols[context->count_protocols].broadcast_socket_port =
2500                                                        ntohs(cli_addr.sin_port);
2501                 listen(fd, 5);
2502
2503                 debug("  Protocol %s broadcast socket %d\n",
2504                                 protocols[context->count_protocols].name,
2505                                                       ntohs(cli_addr.sin_port));
2506
2507                 /* dummy wsi per broadcast proxy socket */
2508
2509                 wsi = malloc(sizeof(struct libwebsocket));
2510                 memset(wsi, 0, sizeof (struct libwebsocket));
2511                 wsi->sock = fd;
2512                 wsi->mode = LWS_CONNMODE_BROADCAST_PROXY_LISTENER;
2513                 wsi->count_active_extensions = 0;
2514                 /* note which protocol we are proxying */
2515                 wsi->protocol_index_for_broadcast_proxy =
2516                                                        context->count_protocols;
2517                 insert_wsi(context, wsi);
2518
2519                 /* list in internal poll array */
2520
2521                 context->fds[context->fds_count].fd = fd;
2522                 context->fds[context->fds_count].events = POLLIN;
2523                 context->fds[context->fds_count].revents = 0;
2524                 context->fds_count++;
2525
2526                 /* external POLL support via protocol 0 */
2527                 context->protocols[0].callback(context, wsi,
2528                         LWS_CALLBACK_ADD_POLL_FD,
2529                         (void *)(long)fd, NULL, POLLIN);
2530         }
2531
2532         return context;
2533 }
2534
2535
2536 #ifndef LWS_NO_FORK
2537
2538 /**
2539  * libwebsockets_fork_service_loop() - Optional helper function forks off
2540  *                                a process for the websocket server loop.
2541  *                              You don't have to use this but if not, you
2542  *                              have to make sure you are calling
2543  *                              libwebsocket_service periodically to service
2544  *                              the websocket traffic
2545  * @context:    server context returned by creation function
2546  */
2547
2548 int
2549 libwebsockets_fork_service_loop(struct libwebsocket_context *context)
2550 {
2551         int fd;
2552         struct sockaddr_in cli_addr;
2553         int n;
2554         int p;
2555
2556         n = fork();
2557         if (n < 0)
2558                 return n;
2559
2560         if (!n) {
2561
2562                 /* main process context */
2563
2564                 /*
2565                  * set up the proxy sockets to allow broadcast from
2566                  * service process context
2567                  */
2568
2569                 for (p = 0; p < context->count_protocols; p++) {
2570                         fd = socket(AF_INET, SOCK_STREAM, 0);
2571                         if (fd < 0) {
2572                                 fprintf(stderr, "Unable to create socket\n");
2573                                 return -1;
2574                         }
2575                         cli_addr.sin_family = AF_INET;
2576                         cli_addr.sin_port = htons(
2577                              context->protocols[p].broadcast_socket_port);
2578                         cli_addr.sin_addr.s_addr = inet_addr("127.0.0.1");
2579                         n = connect(fd, (struct sockaddr *)&cli_addr,
2580                                                                sizeof cli_addr);
2581                         if (n < 0) {
2582                                 fprintf(stderr, "Unable to connect to "
2583                                                 "broadcast socket %d, %s\n",
2584                                                 n, strerror(errno));
2585                                 return -1;
2586                         }
2587
2588                         context->protocols[p].broadcast_socket_user_fd = fd;
2589                 }
2590
2591                 return 0;
2592         }
2593
2594         /* we want a SIGHUP when our parent goes down */
2595         prctl(PR_SET_PDEATHSIG, SIGHUP);
2596
2597         /* in this forked process, sit and service websocket connections */
2598
2599         while (1)
2600                 if (libwebsocket_service(context, 1000))
2601                         return -1;
2602
2603         return 0;
2604 }
2605
2606 #endif
2607
2608 /**
2609  * libwebsockets_get_protocol() - Returns a protocol pointer from a websocket
2610  *                                connection.
2611  * @wsi:        pointer to struct websocket you want to know the protocol of
2612  *
2613  *
2614  *      This is useful to get the protocol to broadcast back to from inside
2615  * the callback.
2616  */
2617
2618 const struct libwebsocket_protocols *
2619 libwebsockets_get_protocol(struct libwebsocket *wsi)
2620 {
2621         return wsi->protocol;
2622 }
2623
2624 /**
2625  * libwebsockets_broadcast() - Sends a buffer to the callback for all active
2626  *                                connections of the given protocol.
2627  * @protocol:   pointer to the protocol you will broadcast to all members of
2628  * @buf:  buffer containing the data to be broadcase.  NOTE: this has to be
2629  *              allocated with LWS_SEND_BUFFER_PRE_PADDING valid bytes before
2630  *              the pointer and LWS_SEND_BUFFER_POST_PADDING afterwards in the
2631  *              case you are calling this function from callback context.
2632  * @len:        length of payload data in buf, starting from buf.
2633  *
2634  *      This function allows bulk sending of a packet to every connection using
2635  * the given protocol.  It does not send the data directly; instead it calls
2636  * the callback with a reason type of LWS_CALLBACK_BROADCAST.  If the callback
2637  * wants to actually send the data for that connection, the callback itself
2638  * should call libwebsocket_write().
2639  *
2640  * libwebsockets_broadcast() can be called from another fork context without
2641  * having to take any care about data visibility between the processes, it'll
2642  * "just work".
2643  */
2644
2645
2646 int
2647 libwebsockets_broadcast(const struct libwebsocket_protocols *protocol,
2648                                                  unsigned char *buf, size_t len)
2649 {
2650         struct libwebsocket_context *context = protocol->owning_server;
2651         int n;
2652         int m;
2653         struct libwebsocket * wsi;
2654
2655         if (!protocol->broadcast_socket_user_fd) {
2656                 /*
2657                  * We are either running unforked / flat, or we are being
2658                  * called from poll thread context
2659                  * eg, from a callback.  In that case don't use sockets for
2660                  * broadcast IPC (since we can't open a socket connection to
2661                  * a socket listening on our own thread) but directly do the
2662                  * send action.
2663                  *
2664                  * Locking is not needed because we are by definition being
2665                  * called in the poll thread context and are serialized.
2666                  */
2667
2668                 for (n = 0; n < FD_HASHTABLE_MODULUS; n++) {
2669
2670                         for (m = 0; m < context->fd_hashtable[n].length; m++) {
2671
2672                                 wsi = context->fd_hashtable[n].wsi[m];
2673
2674                                 if (wsi->mode != LWS_CONNMODE_WS_SERVING)
2675                                         continue;
2676
2677                                 /*
2678                                  * never broadcast to
2679                                  * non-established connections
2680                                  */
2681                                 if (wsi->state != WSI_STATE_ESTABLISHED)
2682                                         continue;
2683
2684                                 /* only broadcast to guys using
2685                                  * requested protocol
2686                                  */
2687                                 if (wsi->protocol != protocol)
2688                                         continue;
2689
2690                                 wsi->protocol->callback(context, wsi,
2691                                          LWS_CALLBACK_BROADCAST,
2692                                          wsi->user_space,
2693                                          buf, len);
2694                         }
2695                 }
2696
2697                 return 0;
2698         }
2699
2700         /*
2701          * We're being called from a different process context than the server
2702          * loop.  Instead of broadcasting directly, we send our
2703          * payload on a socket to do the IPC; the server process will serialize
2704          * the broadcast action in its main poll() loop.
2705          *
2706          * There's one broadcast socket listening for each protocol supported
2707          * set up when the websocket server initializes
2708          */
2709
2710         n = send(protocol->broadcast_socket_user_fd, buf, len, MSG_NOSIGNAL);
2711
2712         return n;
2713 }