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 #include <sys/un.h>
  29 #endif
  30
  31 #ifdef LWS_OPENSSL_SUPPORT
  32 int openssl_websocket_private_data_index;
  33 #endif
  34
  35 /*
  36  * In-place str to lower case
  37  */
  38
  39 static void
  40 strtolower(char *s)
  41 {
  42         while (*s) {
  43                 *s = tolower(*s);
  44                 s++;
  45         }
  46 }
  47
  48 /* file descriptor hash management */
  49
  50 struct libwebsocket *
  51 wsi_from_fd(struct libwebsocket_context *context, int fd)
  52 {
  53         int h = LWS_FD_HASH(fd);
  54         int n = 0;
  55
  56         for (n = 0; n < context->fd_hashtable[h].length; n++)
  57                 if (context->fd_hashtable[h].wsi[n]->sock == fd)
  58                         return context->fd_hashtable[h].wsi[n];
  59
  60         return NULL;
  61 }
  62
  63 int
  64 insert_wsi(struct libwebsocket_context *context, struct libwebsocket *wsi)
  65 {
  66         int h = LWS_FD_HASH(wsi->sock);
  67
  68         if (context->fd_hashtable[h].length == MAX_CLIENTS - 1) {
  69                 fprintf(stderr, "hash table overflow\n");
  70                 return 1;
  71         }
  72
  73         context->fd_hashtable[h].wsi[context->fd_hashtable[h].length++] = wsi;
  74
  75         return 0;
  76 }
  77
  78 int
  79 delete_from_fd(struct libwebsocket_context *context, int fd)
  80 {
  81         int h = LWS_FD_HASH(fd);
  82         int n = 0;
  83
  84         for (n = 0; n < context->fd_hashtable[h].length; n++)
  85                 if (context->fd_hashtable[h].wsi[n]->sock == fd) {
  86                         while (n < context->fd_hashtable[h].length) {
  87                                 context->fd_hashtable[h].wsi[n] =
  88                                             context->fd_hashtable[h].wsi[n + 1];
  89                                 n++;
  90                         }
  91                         context->fd_hashtable[h].length--;
  92
  93                         return 0;
  94                 }
  95
  96         fprintf(stderr, "Failed to find fd %d requested for "
  97                                                    "delete in hashtable\n", fd);
  98         return 1;
  99 }
 100
 101 #ifdef LWS_OPENSSL_SUPPORT
 102 static void
 103 libwebsockets_decode_ssl_error(void)
 104 {
 105         char buf[256];
 106         u_long err;
 107
 108         while ((err = ERR_get_error()) != 0) {
 109                 ERR_error_string_n(err, buf, sizeof(buf));
 110                 fprintf(stderr, "*** %s\n", buf);
 111         }
 112 }
 113 #endif
 114
 115
 116 static int
 117 interface_to_sa(const char* ifname, struct sockaddr_in *addr, size_t addrlen)
 118 {
 119         int rc = -1;
 120 #ifdef WIN32
 121         // TODO
 122 #else
 123         struct ifaddrs *ifr;
 124         struct ifaddrs *ifc;
 125         struct sockaddr_in *sin;
 126
 127         getifaddrs(&ifr);
 128         for (ifc = ifr; ifc != NULL; ifc = ifc->ifa_next) {
 129                 if (strcmp(ifc->ifa_name, ifname))
 130                         continue;
 131                 if (ifc->ifa_addr == NULL)
 132                         continue;
 133                 sin = (struct sockaddr_in *)ifc->ifa_addr;
 134                 if (sin->sin_family != AF_INET)
 135                         continue;
 136                 memcpy(addr, sin, addrlen);
 137                 rc = 0;
 138         }
 139
 140         freeifaddrs(ifr);
 141 #endif
 142         return rc;
 143 }
 144
 145 void
 146 libwebsocket_close_and_free_session(struct libwebsocket_context *context,
 147                          struct libwebsocket *wsi, enum lws_close_status reason)
 148 {
 149         int n;
 150         int old_state;
 151         unsigned char buf[LWS_SEND_BUFFER_PRE_PADDING + 2 +
 152                                                   LWS_SEND_BUFFER_POST_PADDING];
 153         int ret;
 154         int m;
 155         struct lws_tokens eff_buf;
 156
 157         if (!wsi)
 158                 return;
 159
 160         old_state = wsi->state;
 161
 162         if (old_state == WSI_STATE_DEAD_SOCKET)
 163                 return;
 164
 165         wsi->close_reason = reason;
 166
 167         /*
 168          * flush any tx pending from extensions, since we may send close packet
 169          * if there are problems with send, just nuke the connection
 170          */
 171
 172         ret = 1;
 173         while (ret == 1) {
 174
 175                 /* default to nobody has more to spill */
 176
 177                 ret = 0;
 178                 eff_buf.token = NULL;
 179                 eff_buf.token_len = 0;
 180
 181                 /* show every extension the new incoming data */
 182
 183                 for (n = 0; n < wsi->count_active_extensions; n++) {
 184                         m = wsi->active_extensions[n]->callback(
 185                                 wsi->protocol->owning_server, wsi,
 186                                         LWS_EXT_CALLBACK_FLUSH_PENDING_TX,
 187                                    wsi->active_extensions_user[n], &eff_buf, 0);
 188                         if (m < 0) {
 189                                 fprintf(stderr, "Extension reports "
 190                                                                "fatal error\n");
 191                                 goto just_kill_connection;
 192                         }
 193                         if (m)
 194                                 /*
 195                                  * at least one extension told us he has more
 196                                  * to spill, so we will go around again after
 197                                  */
 198                                 ret = 1;
 199                 }
 200
 201                 /* assuming they left us something to send, send it */
 202
 203                 if (eff_buf.token_len)
 204                         if (lws_issue_raw(wsi, (unsigned char *)eff_buf.token,
 205                                                              eff_buf.token_len))
 206                                 goto just_kill_connection;
 207         }
 208
 209         /*
 210          * signal we are closing, libsocket_write will
 211          * add any necessary version-specific stuff.  If the write fails,
 212          * no worries we are closing anyway.  If we didn't initiate this
 213          * close, then our state has been changed to
 214          * WSI_STATE_RETURNED_CLOSE_ALREADY and we will skip this.
 215          *
 216          * Likewise if it's a second call to close this connection after we
 217          * sent the close indication to the peer already, we are in state
 218          * WSI_STATE_AWAITING_CLOSE_ACK and will skip doing this a second time.
 219          */
 220
 221         if (old_state == WSI_STATE_ESTABLISHED &&
 222                                           reason != LWS_CLOSE_STATUS_NOSTATUS) {
 223                 n = libwebsocket_write(wsi, &buf[LWS_SEND_BUFFER_PRE_PADDING],
 224                                                             0, LWS_WRITE_CLOSE);
 225                 if (!n) {
 226                         /*
 227                          * we have sent a nice protocol level indication we
 228                          * now wish to close, we should not send anything more
 229                          */
 230
 231                         wsi->state = WSI_STATE_AWAITING_CLOSE_ACK;
 232
 233                         /* and we should wait for a reply for a bit */
 234
 235                         libwebsocket_set_timeout(wsi,
 236                                                   PENDING_TIMEOUT_CLOSE_ACK, 5);
 237
 238                         fprintf(stderr, "sent close indication, awaiting ack\n");
 239
 240                         return;
 241                 }
 242
 243                 /* else, the send failed and we should just hang up */
 244         }
 245
 246 just_kill_connection:
 247         /*
 248          * we won't be servicing or receiving anything further from this guy
 249          * remove this fd from wsi mapping hashtable
 250          */
 251
 252         delete_from_fd(context, wsi->sock);
 253
 254         /* delete it from the internal poll list if still present */
 255
 256         for (n = 0; n < context->fds_count; n++) {
 257                 if (context->fds[n].fd != wsi->sock)
 258                         continue;
 259                 while (n < context->fds_count - 1) {
 260                         context->fds[n] = context->fds[n + 1];
 261                         n++;
 262                 }
 263                 context->fds_count--;
 264                 /* we only have to deal with one */
 265                 n = context->fds_count;
 266         }
 267
 268         /* remove also from external POLL support via protocol 0 */
 269
 270         context->protocols[0].callback(context, wsi,
 271                     LWS_CALLBACK_DEL_POLL_FD, (void *)(long)wsi->sock, NULL, 0);
 272
 273         wsi->state = WSI_STATE_DEAD_SOCKET;
 274
 275         /* tell the user it's all over for this guy */
 276
 277         if (wsi->protocol && wsi->protocol->callback &&
 278                                              old_state == WSI_STATE_ESTABLISHED)
 279                 wsi->protocol->callback(context, wsi, LWS_CALLBACK_CLOSED,
 280                                                       wsi->user_space, NULL, 0);
 281
 282         /* deallocate any active extension contexts */
 283
 284         for (n = 0; n < wsi->count_active_extensions; n++) {
 285                 if (!wsi->active_extensions[n]->callback)
 286                         continue;
 287
 288                 wsi->active_extensions[n]->callback(context, wsi,
 289                         LWS_EXT_CALLBACK_DESTROY,
 290                         wsi->active_extensions_user[n], NULL, 0);
 291
 292                 free(wsi->active_extensions_user[n]);
 293         }
 294
 295         /* free up his parsing allocations */
 296
 297         for (n = 0; n < WSI_TOKEN_COUNT; n++)
 298                 if (wsi->utf8_token[n].token)
 299                         free(wsi->utf8_token[n].token);
 300
 301 /*      fprintf(stderr, "closing fd=%d\n", wsi->sock); */
 302
 303 #ifdef LWS_OPENSSL_SUPPORT
 304         if (wsi->ssl) {
 305                 n = SSL_get_fd(wsi->ssl);
 306                 SSL_shutdown(wsi->ssl);
 307 #ifdef WIN32
 308                 closesocket(n);
 309 #else
 310                 close(n);
 311 #endif
 312                 SSL_free(wsi->ssl);
 313         } else {
 314 #endif
 315                 shutdown(wsi->sock, SHUT_RDWR);
 316 #ifdef WIN32
 317                 closesocket(wsi->sock);
 318 #else
 319                 close(wsi->sock);
 320 #endif
 321 #ifdef LWS_OPENSSL_SUPPORT
 322         }
 323 #endif
 324         if (wsi->user_space)
 325                 free(wsi->user_space);
 326
 327         free(wsi);
 328 }
 329
 330 /**
 331  * libwebsockets_hangup_on_client() - Server calls to terminate client
 332  *                                      connection
 333  * @context:    libwebsockets context
 334  * @fd:         Connection socket descriptor
 335  */
 336
 337 void
 338 libwebsockets_hangup_on_client(struct libwebsocket_context *context, int fd)
 339 {
 340         struct libwebsocket *wsi = wsi_from_fd(context, fd);
 341
 342         if (wsi == NULL)
 343                 return;
 344
 345         libwebsocket_close_and_free_session(context, wsi,
 346                                                      LWS_CLOSE_STATUS_NOSTATUS);
 347 }
 348
 349
 350 /**
 351  * libwebsockets_get_peer_addresses() - Get client address information
 352  * @fd:         Connection socket descriptor
 353  * @name:       Buffer to take client address name
 354  * @name_len:   Length of client address name buffer
 355  * @rip:        Buffer to take client address IP qotted quad
 356  * @rip_len:    Length of client address IP buffer
 357  *
 358  *      This function fills in @name and @rip with the name and IP of
 359  *      the client connected with socket descriptor @fd.  Names may be
 360  *      truncated if there is not enough room.  If either cannot be
 361  *      determined, they will be returned as valid zero-length strings.
 362  */
 363
 364 void
 365 libwebsockets_get_peer_addresses(int fd, char *name, int name_len,
 366                                         char *rip, int rip_len)
 367 {
 368         unsigned int len;
 369         struct sockaddr_in sin;
 370         struct hostent *host;
 371         struct hostent *host1;
 372         char ip[128];
 373         unsigned char *p;
 374         int n;
 375         struct sockaddr_un *un;
 376
 377         rip[0] = '\0';
 378         name[0] = '\0';
 379
 380         len = sizeof sin;
 381         if (getpeername(fd, (struct sockaddr *) &sin, &len) < 0) {
 382                 perror("getpeername");
 383                 return;
 384         }
 385
 386         host = gethostbyaddr((char *) &sin.sin_addr, sizeof sin.sin_addr,
 387                                                                        AF_INET);
 388         if (host == NULL) {
 389                 perror("gethostbyaddr");
 390                 return;
 391         }
 392
 393         strncpy(name, host->h_name, name_len);
 394         name[name_len - 1] = '\0';
 395
 396         host1 = gethostbyname(host->h_name);
 397         if (host1 == NULL)
 398                 return;
 399         p = (unsigned char *)host1;
 400         n = 0;
 401         while (p != NULL) {
 402                 p = (unsigned char *)host1->h_addr_list[n++];
 403                 if (p == NULL)
 404                         continue;
 405                 if ((host1->h_addrtype != AF_INET)
 406 #ifdef AF_LOCAL
 407                         && (host1->h_addrtype != AF_LOCAL)
 408 #endif
 409                         )
 410                         continue;
 411
 412                 if (host1->h_addrtype == AF_INET)
 413                         sprintf(ip, "%u.%u.%u.%u", p[0], p[1], p[2], p[3]);
 414 #ifdef AF_LOCAL
 415                 else {
 416                         un = (struct sockaddr_un *)p;
 417                         strncpy(ip, un->sun_path, sizeof(ip) -1);
 418                         ip[sizeof(ip) - 1] = '\0';
 419                 }
 420 #endif
 421                 p = NULL;
 422                 strncpy(rip, ip, rip_len);
 423                 rip[rip_len - 1] = '\0';
 424         }
 425 }
 426
 427 int libwebsockets_get_random(struct libwebsocket_context *context,
 428                                                              void *buf, int len)
 429 {
 430         int n;
 431         char *p = buf;
 432
 433 #ifdef WIN32
 434         for (n = 0; n < len; n++)
 435                 p[n] = (unsigned char)rand();
 436 #else
 437         n = read(context->fd_random, p, len);
 438 #endif
 439
 440         return n;
 441 }
 442
 443 unsigned char *
 444 libwebsockets_SHA1(const unsigned char *d, size_t n, unsigned char *md)
 445 {
 446         return SHA1(d, n, md);
 447 }
 448
 449 void libwebsockets_00_spaceout(char *key, int spaces, int seed)
 450 {
 451         char *p;
 452
 453         key++;
 454         while (spaces--) {
 455                 if (*key && (seed & 1))
 456                         key++;
 457                 seed >>= 1;
 458
 459                 p = key + strlen(key);
 460                 while (p >= key) {
 461                         p[1] = p[0];
 462                         p--;
 463                 }
 464                 *key++ = ' ';
 465         }
 466 }
 467
 468 void libwebsockets_00_spam(char *key, int count, int seed)
 469 {
 470         char *p;
 471
 472         key++;
 473         while (count--) {
 474
 475                 if (*key && (seed & 1))
 476                         key++;
 477                 seed >>= 1;
 478
 479                 p = key + strlen(key);
 480                 while (p >= key) {
 481                         p[1] = p[0];
 482                         p--;
 483                 }
 484                 *key++ = 0x21 + ((seed & 0xffff) % 15);
 485                 /* 4 would use it up too fast.. not like it matters */
 486                 seed >>= 1;
 487         }
 488 }
 489
 490 int lws_send_pipe_choked(struct libwebsocket *wsi)
 491 {
 492         struct pollfd fds;
 493
 494         fds.fd = wsi->sock;
 495         fds.events = POLLOUT;
 496         fds.revents = 0;
 497
 498         if (poll(&fds, 1, 0) != 1)
 499                 return 1;
 500
 501         if ((fds.revents & POLLOUT) == 0)
 502                 return 1;
 503
 504         /* okay to send another packet without blocking */
 505
 506         return 0;
 507 }
 508
 509 static int
 510 lws_handle_POLLOUT_event(struct libwebsocket_context *context,
 511                                 struct libwebsocket *wsi, struct pollfd *pollfd)
 512 {
 513         struct lws_tokens eff_buf;
 514         int n;
 515         int ret;
 516         int m;
 517
 518         if (!wsi->extension_data_pending)
 519                 goto user_service;
 520
 521         /*
 522          * check in on the active extensions, see if they
 523          * had pending stuff to spill... they need to get the
 524          * first look-in otherwise sequence will be disordered
 525          *
 526          * NULL, zero-length eff_buf means just spill pending
 527          */
 528
 529         ret = 1;
 530         while (ret == 1) {
 531
 532                 /* default to nobody has more to spill */
 533
 534                 ret = 0;
 535                 eff_buf.token = NULL;
 536                 eff_buf.token_len = 0;
 537
 538                 /* give every extension a chance to spill */
 539
 540                 for (n = 0; n < wsi->count_active_extensions; n++) {
 541                         m = wsi->active_extensions[n]->callback(
 542                                 wsi->protocol->owning_server, wsi,
 543                                         LWS_EXT_CALLBACK_PACKET_TX_PRESEND,
 544                                    wsi->active_extensions_user[n], &eff_buf, 0);
 545                         if (m < 0) {
 546                                 fprintf(stderr, "extension reports fatal error\n");
 547                                 return -1;
 548                         }
 549                         if (m)
 550                                 /*
 551                                  * at least one extension told us he has more
 552                                  * to spill, so we will go around again after
 553                                  */
 554                                 ret = 1;
 555                 }
 556
 557                 /* assuming they gave us something to send, send it */
 558
 559                 if (eff_buf.token_len) {
 560                         if (lws_issue_raw(wsi, (unsigned char *)eff_buf.token,
 561                                                              eff_buf.token_len))
 562                                 return -1;
 563                 } else
 564                         continue;
 565
 566                 /* no extension has more to spill */
 567
 568                 if (!ret)
 569                         continue;
 570
 571                 /*
 572                  * There's more to spill from an extension, but we just sent
 573                  * something... did that leave the pipe choked?
 574                  */
 575
 576                 if (!lws_send_pipe_choked(wsi))
 577                         /* no we could add more */
 578                         continue;
 579
 580                 fprintf(stderr, "choked in POLLOUT service\n");
 581
 582                 /*
 583                  * Yes, he's choked.  Leave the POLLOUT masked on so we will
 584                  * come back here when he is unchoked.  Don't call the user
 585                  * callback to enforce ordering of spilling, he'll get called
 586                  * when we come back here and there's nothing more to spill.
 587                  */
 588
 589                 return 0;
 590         }
 591
 592         wsi->extension_data_pending = 0;
 593
 594 user_service:
 595         /* one shot */
 596
 597         pollfd->events &= ~POLLOUT;
 598
 599         /* external POLL support via protocol 0 */
 600         context->protocols[0].callback(context, wsi,
 601                 LWS_CALLBACK_CLEAR_MODE_POLL_FD,
 602                 (void *)(long)wsi->sock, NULL, POLLOUT);
 603
 604         if (wsi->mode == LWS_CONNMODE_WS_CLIENT)
 605                 n = LWS_CALLBACK_CLIENT_WRITEABLE;
 606         else
 607                 n = LWS_CALLBACK_SERVER_WRITEABLE;
 608
 609         wsi->protocol->callback(context, wsi, n, wsi->user_space, NULL, 0);
 610
 611         return 0;
 612 }
 613
 614
 615
 616 /**
 617  * libwebsocket_service_fd() - Service polled socket with something waiting
 618  * @context:    Websocket context
 619  * @pollfd:     The pollfd entry describing the socket fd and which events
 620  *              happened.
 621  *
 622  *      This function closes any active connections and then frees the
 623  *      context.  After calling this, any further use of the context is
 624  *      undefined.
 625  */
 626
 627 int
 628 libwebsocket_service_fd(struct libwebsocket_context *context,
 629                                                           struct pollfd *pollfd)
 630 {
 631         unsigned char buf[LWS_SEND_BUFFER_PRE_PADDING + 1 + MAX_BROADCAST_PAYLOAD +
 632                                                   LWS_SEND_BUFFER_POST_PADDING];
 633         struct libwebsocket *wsi;
 634         struct libwebsocket *new_wsi;
 635         int n;
 636         int m;
 637         size_t len;
 638         int accept_fd;
 639         unsigned int clilen;
 640         struct sockaddr_in cli_addr;
 641         struct timeval tv;
 642         static const char magic_websocket_guid[] =
 643                                          "258EAFA5-E914-47DA-95CA-C5AB0DC85B11";
 644         static const char magic_websocket_04_masking_guid[] =
 645                                          "61AC5F19-FBBA-4540-B96F-6561F1AB40A8";
 646         char hash[20];
 647         char pkt[1024];
 648         char *p = &pkt[0];
 649         const char *pc;
 650         const char *c;
 651         int more = 1;
 652         int okay = 0;
 653         char ext_name[128];
 654         struct lws_tokens eff_buf;
 655         int ext_count = 0;
 656         struct libwebsocket_extension *ext;
 657         int opt = 1;
 658
 659 #ifdef LWS_OPENSSL_SUPPORT
 660         char ssl_err_buf[512];
 661 #endif
 662         /*
 663          * you can call us with pollfd = NULL to just allow the once-per-second
 664          * global timeout checks; if less than a second since the last check
 665          * it returns immediately then.
 666          */
 667
 668         gettimeofday(&tv, NULL);
 669
 670         if (context->last_timeout_check_s != tv.tv_sec) {
 671                 context->last_timeout_check_s = tv.tv_sec;
 672
 673                 /* global timeout check once per second */
 674
 675                 for (n = 0; n < context->fds_count; n++) {
 676                         wsi = wsi_from_fd(context, context->fds[n].fd);
 677                         if (!wsi->pending_timeout)
 678                                 continue;
 679
 680                         /*
 681                          * if we went beyond the allowed time, kill the
 682                          * connection
 683                          */
 684
 685                         if (tv.tv_sec > wsi->pending_timeout_limit) {
 686                                 fprintf(stderr, "TIMEDOUT WAITING\n");
 687                                 libwebsocket_close_and_free_session(context,
 688                                                 wsi, LWS_CLOSE_STATUS_NOSTATUS);
 689                         }
 690                 }
 691         }
 692
 693         /* just here for timeout management? */
 694
 695         if (pollfd == NULL)
 696                 return 0;
 697
 698         /* no, here to service a socket descriptor */
 699
 700         wsi = wsi_from_fd(context, pollfd->fd);
 701
 702         if (wsi == NULL)
 703                 return 1;
 704
 705         switch (wsi->mode) {
 706         case LWS_CONNMODE_SERVER_LISTENER:
 707
 708                 /* pollin means a client has connected to us then */
 709
 710                 if (!pollfd->revents & POLLIN)
 711                         break;
 712
 713                 /* listen socket got an unencrypted connection... */
 714
 715                 clilen = sizeof(cli_addr);
 716                 accept_fd  = accept(pollfd->fd, (struct sockaddr *)&cli_addr,
 717                                                                        &clilen);
 718                 if (accept_fd < 0) {
 719                         fprintf(stderr, "ERROR on accept");
 720                         break;
 721                 }
 722
 723                 /* Disable Nagle */
 724                 opt = 1;
 725                 setsockopt(accept_fd, SOL_TCP, TCP_NODELAY, &opt, sizeof(opt));
 726
 727                 if (context->fds_count >= MAX_CLIENTS) {
 728                         fprintf(stderr, "too busy to accept new client\n");
 729 #ifdef WIN32
 730                         closesocket(accept_fd);
 731 #else
 732                         close(accept_fd);
 733 #endif
 734                         break;
 735                 }
 736
 737                 /*
 738                  * look at who we connected to and give user code a chance
 739                  * to reject based on client IP.  There's no protocol selected
 740                  * yet so we issue this to protocols[0]
 741                  */
 742
 743                 if ((context->protocols[0].callback)(context, wsi,
 744                                 LWS_CALLBACK_FILTER_NETWORK_CONNECTION,
 745                                              (void*)(long)accept_fd, NULL, 0)) {
 746                         fprintf(stderr, "Callback denied network connection\n");
 747 #ifdef WIN32
 748                         closesocket(accept_fd);
 749 #else
 750                         close(accept_fd);
 751 #endif
 752                         break;
 753                 }
 754
 755                 /* accepting connection to main listener */
 756
 757                 new_wsi = malloc(sizeof(struct libwebsocket));
 758                 if (new_wsi == NULL) {
 759                         fprintf(stderr, "Out of memory for new connection\n");
 760                         break;
 761                 }
 762
 763                 memset(new_wsi, 0, sizeof (struct libwebsocket));
 764                 new_wsi->sock = accept_fd;
 765                 new_wsi->count_active_extensions = 0;
 766                 new_wsi->pending_timeout = NO_PENDING_TIMEOUT;
 767
 768 #ifdef LWS_OPENSSL_SUPPORT
 769                 new_wsi->ssl = NULL;
 770
 771                 if (context->use_ssl) {
 772
 773                         new_wsi->ssl = SSL_new(context->ssl_ctx);
 774                         if (new_wsi->ssl == NULL) {
 775                                 fprintf(stderr, "SSL_new failed: %s\n",
 776                                     ERR_error_string(SSL_get_error(
 777                                     new_wsi->ssl, 0), NULL));
 778                                     libwebsockets_decode_ssl_error();
 779                                 free(new_wsi);
 780                                 break;
 781                         }
 782
 783                         SSL_set_fd(new_wsi->ssl, accept_fd);
 784
 785                         n = SSL_accept(new_wsi->ssl);
 786                         if (n != 1) {
 787                                 /*
 788                                  * browsers seem to probe with various
 789                                  * ssl params which fail then retry
 790                                  * and succeed
 791                                  */
 792                                 debug("SSL_accept failed skt %u: %s\n",
 793                                       pollfd->fd,
 794                                       ERR_error_string(SSL_get_error(
 795                                       new_wsi->ssl, n), NULL));
 796                                 SSL_free(
 797                                        new_wsi->ssl);
 798                                 free(new_wsi);
 799                                 break;
 800                         }
 801
 802                         debug("accepted new SSL conn  "
 803                               "port %u on fd=%d SSL ver %s\n",
 804                                 ntohs(cli_addr.sin_port), accept_fd,
 805                                   SSL_get_version(new_wsi->ssl));
 806
 807                 } else
 808 #endif
 809                         debug("accepted new conn  port %u on fd=%d\n",
 810                                           ntohs(cli_addr.sin_port), accept_fd);
 811
 812                 /* intialize the instance struct */
 813
 814                 new_wsi->state = WSI_STATE_HTTP;
 815                 new_wsi->name_buffer_pos = 0;
 816                 new_wsi->mode = LWS_CONNMODE_WS_SERVING;
 817
 818                 for (n = 0; n < WSI_TOKEN_COUNT; n++) {
 819                         new_wsi->utf8_token[n].token = NULL;
 820                         new_wsi->utf8_token[n].token_len = 0;
 821                 }
 822
 823                 /*
 824                  * these can only be set once the protocol is known
 825                  * we set an unestablished connection's protocol pointer
 826                  * to the start of the supported list, so it can look
 827                  * for matching ones during the handshake
 828                  */
 829                 new_wsi->protocol = context->protocols;
 830                 new_wsi->user_space = NULL;
 831
 832                 /*
 833                  * Default protocol is 76 / 00
 834                  * After 76, there's a header specified to inform which
 835                  * draft the client wants, when that's seen we modify
 836                  * the individual connection's spec revision accordingly
 837                  */
 838                 new_wsi->ietf_spec_revision = 0;
 839
 840                 insert_wsi(context, new_wsi);
 841
 842                 /*
 843                  * make sure NO events are seen yet on this new socket
 844                  * (otherwise we inherit old fds[client].revents from
 845                  * previous socket there and die mysteriously! )
 846                  */
 847                 context->fds[context->fds_count].revents = 0;
 848
 849                 context->fds[context->fds_count].events = POLLIN;
 850                 context->fds[context->fds_count++].fd = accept_fd;
 851
 852                 /* external POLL support via protocol 0 */
 853                 context->protocols[0].callback(context, new_wsi,
 854                         LWS_CALLBACK_ADD_POLL_FD,
 855                         (void *)(long)accept_fd, NULL, POLLIN);
 856
 857                 break;
 858
 859         case LWS_CONNMODE_BROADCAST_PROXY_LISTENER:
 860
 861                 /* as we are listening, POLLIN means accept() is needed */
 862
 863                 if (!pollfd->revents & POLLIN)
 864                         break;
 865
 866                 /* listen socket got an unencrypted connection... */
 867
 868                 clilen = sizeof(cli_addr);
 869                 accept_fd  = accept(pollfd->fd, (struct sockaddr *)&cli_addr,
 870                                                                        &clilen);
 871                 if (accept_fd < 0) {
 872                         fprintf(stderr, "ERROR on accept");
 873                         break;
 874                 }
 875
 876                 if (context->fds_count >= MAX_CLIENTS) {
 877                         fprintf(stderr, "too busy to accept new broadcast "
 878                                                               "proxy client\n");
 879 #ifdef WIN32
 880                         closesocket(accept_fd);
 881 #else
 882                         close(accept_fd);
 883 #endif
 884                         break;
 885                 }
 886
 887                 /* create a dummy wsi for the connection and add it */
 888
 889                 new_wsi = malloc(sizeof(struct libwebsocket));
 890                 memset(new_wsi, 0, sizeof (struct libwebsocket));
 891                 new_wsi->sock = accept_fd;
 892                 new_wsi->mode = LWS_CONNMODE_BROADCAST_PROXY;
 893                 new_wsi->state = WSI_STATE_ESTABLISHED;
 894                 new_wsi->count_active_extensions = 0;
 895                 /* note which protocol we are proxying */
 896                 new_wsi->protocol_index_for_broadcast_proxy =
 897                                         wsi->protocol_index_for_broadcast_proxy;
 898                 insert_wsi(context, new_wsi);
 899
 900                 /* add connected socket to internal poll array */
 901
 902                 context->fds[context->fds_count].revents = 0;
 903                 context->fds[context->fds_count].events = POLLIN;
 904                 context->fds[context->fds_count++].fd = accept_fd;
 905
 906                 /* external POLL support via protocol 0 */
 907                 context->protocols[0].callback(context, new_wsi,
 908                         LWS_CALLBACK_ADD_POLL_FD,
 909                         (void *)(long)accept_fd, NULL, POLLIN);
 910
 911                 break;
 912
 913         case LWS_CONNMODE_BROADCAST_PROXY:
 914
 915                 /* handle session socket closed */
 916
 917                 if (pollfd->revents & (POLLERR | POLLHUP)) {
 918
 919                         debug("Session Socket %p (fd=%d) dead\n",
 920                                 (void *)wsi, pollfd->fd);
 921
 922                         libwebsocket_close_and_free_session(context, wsi,
 923                                                        LWS_CLOSE_STATUS_NORMAL);
 924                         return 1;
 925                 }
 926
 927                 /*
 928                  * either extension code with stuff to spill, or the user code,
 929                  * requested a callback when it was OK to write
 930                  */
 931
 932                 if (pollfd->revents & POLLOUT)
 933                         if (lws_handle_POLLOUT_event(context, wsi, pollfd) < 0) {
 934                                 libwebsocket_close_and_free_session(context, wsi,
 935                                                        LWS_CLOSE_STATUS_NORMAL);
 936                                 return 1;
 937                         }
 938
 939                 /* any incoming data ready? */
 940
 941                 if (!(pollfd->revents & POLLIN))
 942                         break;
 943
 944                 /* get the issued broadcast payload from the socket */
 945
 946                 len = read(pollfd->fd, buf + LWS_SEND_BUFFER_PRE_PADDING,
 947                                                          MAX_BROADCAST_PAYLOAD);
 948                 if (len < 0) {
 949                         fprintf(stderr, "Error reading broadcast payload\n");
 950                         break;
 951                 }
 952
 953                 /* broadcast it to all guys with this protocol index */
 954
 955                 for (n = 0; n < FD_HASHTABLE_MODULUS; n++) {
 956
 957                         for (m = 0; m < context->fd_hashtable[n].length; m++) {
 958
 959                                 new_wsi = context->fd_hashtable[n].wsi[m];
 960
 961                                 /* only to clients we are serving to */
 962
 963                                 if (new_wsi->mode != LWS_CONNMODE_WS_SERVING)
 964                                         continue;
 965
 966                                 /*
 967                                  * never broadcast to non-established
 968                                  * connection
 969                                  */
 970
 971                                 if (new_wsi->state != WSI_STATE_ESTABLISHED)
 972                                         continue;
 973
 974                                 /*
 975                                  * only broadcast to connections using
 976                                  * the requested protocol
 977                                  */
 978
 979                                 if (new_wsi->protocol->protocol_index !=
 980                                         wsi->protocol_index_for_broadcast_proxy)
 981                                         continue;
 982
 983                                 /* broadcast it to this connection */
 984
 985                                 new_wsi->protocol->callback(context, new_wsi,
 986                                         LWS_CALLBACK_BROADCAST,
 987                                         new_wsi->user_space,
 988                                         buf + LWS_SEND_BUFFER_PRE_PADDING, len);
 989                         }
 990                 }
 991                 break;
 992
 993         case LWS_CONNMODE_WS_CLIENT_WAITING_PROXY_REPLY:
 994
 995                 /* handle proxy hung up on us */
 996
 997                 if (pollfd->revents & (POLLERR | POLLHUP)) {
 998
 999                         fprintf(stderr, "Proxy connection %p (fd=%d) dead\n",
1000                                 (void *)wsi, pollfd->fd);
1001
1002                         libwebsocket_close_and_free_session(context, wsi,
1003                                                      LWS_CLOSE_STATUS_NOSTATUS);
1004                         return 1;
1005                 }
1006
1007                 n = recv(wsi->sock, pkt, sizeof pkt, 0);
1008                 if (n < 0) {
1009                         libwebsocket_close_and_free_session(context, wsi,
1010                                                      LWS_CLOSE_STATUS_NOSTATUS);
1011                         fprintf(stderr, "ERROR reading from proxy socket\n");
1012                         return 1;
1013                 }
1014
1015                 pkt[13] = '\0';
1016                 if (strcmp(pkt, "HTTP/1.0 200 ") != 0) {
1017                         libwebsocket_close_and_free_session(context, wsi,
1018                                                      LWS_CLOSE_STATUS_NOSTATUS);
1019                         fprintf(stderr, "ERROR from proxy: %s\n", pkt);
1020                         return 1;
1021                 }
1022
1023                 /* clear his proxy connection timeout */
1024
1025                 libwebsocket_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
1026
1027                 /* fallthru */
1028
1029         case LWS_CONNMODE_WS_CLIENT_ISSUE_HANDSHAKE:
1030
1031         #ifdef LWS_OPENSSL_SUPPORT
1032                 if (wsi->use_ssl) {
1033
1034                         wsi->ssl = SSL_new(context->ssl_client_ctx);
1035                         wsi->client_bio = BIO_new_socket(wsi->sock,
1036                                                                    BIO_NOCLOSE);
1037                         SSL_set_bio(wsi->ssl, wsi->client_bio, wsi->client_bio);
1038
1039                         SSL_set_ex_data(wsi->ssl,
1040                                         openssl_websocket_private_data_index,
1041                                                                        context);
1042
1043                         if (SSL_connect(wsi->ssl) <= 0) {
1044                                 fprintf(stderr, "SSL connect error %s\n",
1045                                         ERR_error_string(ERR_get_error(),
1046                                                                   ssl_err_buf));
1047                                 libwebsocket_close_and_free_session(context, wsi,
1048                                                      LWS_CLOSE_STATUS_NOSTATUS);
1049                                 return 1;
1050                         }
1051
1052                         n = SSL_get_verify_result(wsi->ssl);
1053                         if ((n != X509_V_OK) && (
1054                                 n != X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT ||
1055                                                            wsi->use_ssl != 2)) {
1056
1057                                 fprintf(stderr, "server's cert didn't "
1058                                                            "look good %d\n", n);
1059                                 libwebsocket_close_and_free_session(context,
1060                                                 wsi, LWS_CLOSE_STATUS_NOSTATUS);
1061                                 return 1;
1062                         }
1063                 } else {
1064                         wsi->ssl = NULL;
1065         #endif
1066
1067
1068         #ifdef LWS_OPENSSL_SUPPORT
1069                 }
1070         #endif
1071
1072                 /*
1073                  * create the random key
1074                  */
1075
1076                 n = libwebsockets_get_random(context, hash, 16);
1077                 if (n != 16) {
1078                         fprintf(stderr, "Unable to read from random dev %s\n",
1079                                                         SYSTEM_RANDOM_FILEPATH);
1080                         free(wsi->c_path);
1081                         free(wsi->c_host);
1082                         if (wsi->c_origin)
1083                                 free(wsi->c_origin);
1084                         if (wsi->c_protocol)
1085                                 free(wsi->c_protocol);
1086                         libwebsocket_close_and_free_session(context, wsi,
1087                                                      LWS_CLOSE_STATUS_NOSTATUS);
1088                         return 1;
1089                 }
1090
1091                 lws_b64_encode_string(hash, 16, wsi->key_b64,
1092                                                            sizeof wsi->key_b64);
1093
1094                 /*
1095                  * 00 example client handshake
1096                  *
1097                  * GET /socket.io/websocket HTTP/1.1
1098                  * Upgrade: WebSocket
1099                  * Connection: Upgrade
1100                  * Host: 127.0.0.1:9999
1101                  * Origin: http://127.0.0.1
1102                  * Sec-WebSocket-Key1: 1 0 2#0W 9 89 7  92 ^
1103                  * Sec-WebSocket-Key2: 7 7Y 4328 B2v[8(z1
1104                  * Cookie: socketio=websocket
1105                  *
1106                  * (Á®Ä0¶†≥
1107                  *
1108                  * 04 example client handshake
1109                  *
1110                  * GET /chat HTTP/1.1
1111                  * Host: server.example.com
1112                  * Upgrade: websocket
1113                  * Connection: Upgrade
1114                  * Sec-WebSocket-Key: dGhlIHNhbXBsZSBub25jZQ==
1115                  * Sec-WebSocket-Origin: http://example.com
1116                  * Sec-WebSocket-Protocol: chat, superchat
1117                  * Sec-WebSocket-Version: 4
1118                  */
1119
1120                 p += sprintf(p, "GET %s HTTP/1.1\x0d\x0a", wsi->c_path);
1121
1122                 if (wsi->ietf_spec_revision == 0) {
1123                         unsigned char spaces_1, spaces_2;
1124                         unsigned int max_1, max_2;
1125                         unsigned int num_1, num_2;
1126                         unsigned long product_1, product_2;
1127                         char key_1[40];
1128                         char key_2[40];
1129                         unsigned int seed;
1130                         unsigned int count;
1131                         char challenge[16];
1132
1133                         libwebsockets_get_random(context, &spaces_1,
1134                                                                   sizeof(char));
1135                         libwebsockets_get_random(context, &spaces_2,
1136                                                                   sizeof(char));
1137
1138                         spaces_1 = (spaces_1 % 12) + 1;
1139                         spaces_2 = (spaces_2 % 12) + 1;
1140
1141                         max_1 = 4294967295 / spaces_1;
1142                         max_2 = 4294967295 / spaces_2;
1143
1144                         libwebsockets_get_random(context, &num_1, sizeof(int));
1145                         libwebsockets_get_random(context, &num_2, sizeof(int));
1146
1147                         num_1 = (num_1 % max_1);
1148                         num_2 = (num_2 % max_2);
1149
1150                         challenge[0] = num_1 >> 24;
1151                         challenge[1] = num_1 >> 16;
1152                         challenge[2] = num_1 >> 8;
1153                         challenge[3] = num_1;
1154                         challenge[4] = num_2 >> 24;
1155                         challenge[5] = num_2 >> 16;
1156                         challenge[6] = num_2 >> 8;
1157                         challenge[7] = num_2;
1158
1159                         product_1 = num_1 * spaces_1;
1160                         product_2 = num_2 * spaces_2;
1161
1162                         sprintf(key_1, "%lu", product_1);
1163                         sprintf(key_2, "%lu", product_2);
1164
1165                         libwebsockets_get_random(context, &seed, sizeof(int));
1166                         libwebsockets_get_random(context, &count, sizeof(int));
1167
1168                         libwebsockets_00_spam(key_1, (count % 12) + 1, seed);
1169
1170                         libwebsockets_get_random(context, &seed, sizeof(int));
1171                         libwebsockets_get_random(context, &count, sizeof(int));
1172
1173                         libwebsockets_00_spam(key_2, (count % 12) + 1, seed);
1174
1175                         libwebsockets_get_random(context, &seed, sizeof(int));
1176
1177                         libwebsockets_00_spaceout(key_1, spaces_1, seed);
1178                         libwebsockets_00_spaceout(key_2, spaces_2, seed >> 16);
1179
1180                         p += sprintf(p, "Upgrade: websocket\x0d\x0a"
1181                                 "Connection: Upgrade\x0d\x0aHost: %s\x0d\x0a",
1182                                 wsi->c_host);
1183                         if (wsi->c_origin)
1184                                 p += sprintf(p, "Origin: %s\x0d\x0a",
1185                                 wsi->c_origin);
1186
1187                         if (wsi->c_protocol)
1188                                 p += sprintf(p, "Sec-WebSocket-Protocol: %s"
1189                                                  "\x0d\x0a", wsi->c_protocol);
1190
1191                         p += sprintf(p, "Sec-WebSocket-Key1: %s\x0d\x0a",
1192                                 key_1);
1193                         p += sprintf(p, "Sec-WebSocket-Key2: %s\x0d\x0a",
1194                                 key_2);
1195
1196                         /* give userland a chance to append, eg, cookies */
1197
1198                         context->protocols[0].callback(context, wsi,
1199                                 LWS_CALLBACK_CLIENT_APPEND_HANDSHAKE_HEADER,
1200                                         NULL, &p, (pkt + sizeof(pkt)) - p - 12);
1201
1202                         p += sprintf(p, "\x0d\x0a");
1203
1204                         if (libwebsockets_get_random(context, p, 8) != 8)
1205                                 return -1;
1206                         memcpy(&challenge[8], p, 8);
1207                         p += 8;
1208
1209                         /* precompute what we want to see from the server */
1210
1211                         MD5((unsigned char *)challenge, 16,
1212                            (unsigned char *)wsi->initial_handshake_hash_base64);
1213
1214                         goto issue_hdr;
1215                 }
1216
1217                 p += sprintf(p, "Host: %s\x0d\x0a", wsi->c_host);
1218                 p += sprintf(p, "Upgrade: websocket\x0d\x0a");
1219                 p += sprintf(p, "Connection: Upgrade\x0d\x0a"
1220                                         "Sec-WebSocket-Key: ");
1221                 strcpy(p, wsi->key_b64);
1222                 p += strlen(wsi->key_b64);
1223                 p += sprintf(p, "\x0d\x0a");
1224                 if (wsi->c_origin)
1225                         p += sprintf(p, "Sec-WebSocket-Origin: %s\x0d\x0a",
1226                                                                  wsi->c_origin);
1227                 if (wsi->c_protocol)
1228                         p += sprintf(p, "Sec-WebSocket-Protocol: %s\x0d\x0a",
1229                                                                wsi->c_protocol);
1230
1231                 /* tell the server what extensions we could support */
1232
1233                 p += sprintf(p, "Sec-WebSocket-Extensions: ");
1234
1235                 ext =context->extensions;
1236                 while (ext && ext->callback) {
1237
1238                         n = 0;
1239                         n = context->protocols[0].callback(context, wsi,
1240                                 LWS_CALLBACK_CLIENT_CONFIRM_EXTENSION_SUPPORTED,
1241                                         wsi->user_space, (char *)ext->name, 0);
1242
1243                         /*
1244                          * zero return from callback means
1245                          * go ahead and allow the extension,
1246                          * it's what we get if the callback is
1247                          * unhandled
1248                          */
1249
1250                         if (n) {
1251                                 ext++;
1252                                 continue;
1253                         }
1254
1255                         /* apply it */
1256
1257                         if (ext_count)
1258                                 *p++ = ',';
1259                         p += sprintf(p, "%s", ext->name);
1260                         ext_count++;
1261
1262                         ext++;
1263                 }
1264
1265                 p += sprintf(p, "\x0d\x0a");
1266
1267                 if (wsi->ietf_spec_revision)
1268                         p += sprintf(p, "Sec-WebSocket-Version: %d\x0d\x0a",
1269                                                        wsi->ietf_spec_revision);
1270
1271                 /* give userland a chance to append, eg, cookies */
1272
1273                 context->protocols[0].callback(context, wsi,
1274                         LWS_CALLBACK_CLIENT_APPEND_HANDSHAKE_HEADER,
1275                         NULL, &p, (pkt + sizeof(pkt)) - p - 12);
1276
1277                 p += sprintf(p, "\x0d\x0a");
1278
1279                 /* prepare the expected server accept response */
1280
1281                 strcpy((char *)buf, wsi->key_b64);
1282                 strcpy((char *)&buf[strlen((char *)buf)], magic_websocket_guid);
1283
1284                 SHA1(buf, strlen((char *)buf), (unsigned char *)hash);
1285
1286                 lws_b64_encode_string(hash, 20,
1287                                 wsi->initial_handshake_hash_base64,
1288                                      sizeof wsi->initial_handshake_hash_base64);
1289
1290 issue_hdr:
1291
1292                 /* done with these now */
1293
1294                 free(wsi->c_path);
1295                 free(wsi->c_host);
1296                 if (wsi->c_origin)
1297                         free(wsi->c_origin);
1298
1299                 /* send our request to the server */
1300
1301         #ifdef LWS_OPENSSL_SUPPORT
1302                 if (wsi->use_ssl)
1303                         n = SSL_write(wsi->ssl, pkt, p - pkt);
1304                 else
1305         #endif
1306                         n = send(wsi->sock, pkt, p - pkt, 0);
1307
1308                 if (n < 0) {
1309                         fprintf(stderr, "ERROR writing to client socket\n");
1310                         libwebsocket_close_and_free_session(context, wsi,
1311                                                      LWS_CLOSE_STATUS_NOSTATUS);
1312                         return 1;
1313                 }
1314
1315                 wsi->parser_state = WSI_TOKEN_NAME_PART;
1316                 wsi->mode = LWS_CONNMODE_WS_CLIENT_WAITING_SERVER_REPLY;
1317                 libwebsocket_set_timeout(wsi,
1318                                 PENDING_TIMEOUT_AWAITING_SERVER_RESPONSE, 5);
1319
1320                 break;
1321
1322         case LWS_CONNMODE_WS_CLIENT_WAITING_SERVER_REPLY:
1323
1324                 /* handle server hung up on us */
1325
1326                 if (pollfd->revents & (POLLERR | POLLHUP)) {
1327
1328                         fprintf(stderr, "Server connection %p (fd=%d) dead\n",
1329                                 (void *)wsi, pollfd->fd);
1330
1331                         goto bail3;
1332                 }
1333
1334
1335                 /* interpret the server response */
1336
1337                 /*
1338                  *  HTTP/1.1 101 Switching Protocols
1339                  *  Upgrade: websocket
1340                  *  Connection: Upgrade
1341                  *  Sec-WebSocket-Accept: me89jWimTRKTWwrS3aRrL53YZSo=
1342                  *  Sec-WebSocket-Nonce: AQIDBAUGBwgJCgsMDQ4PEC==
1343                  *  Sec-WebSocket-Protocol: chat
1344                  */
1345
1346         #ifdef LWS_OPENSSL_SUPPORT
1347                 if (wsi->use_ssl)
1348                         len = SSL_read(wsi->ssl, pkt, sizeof pkt);
1349                 else
1350         #endif
1351                         len = recv(wsi->sock, pkt, sizeof pkt, 0);
1352
1353                 if (len < 0) {
1354                         fprintf(stderr,
1355                                   "libwebsocket_client_handshake read error\n");
1356                         goto bail3;
1357                 }
1358
1359                 p = pkt;
1360                 for (n = 0; n < len; n++)
1361                         libwebsocket_parse(wsi, *p++);
1362
1363                 if (wsi->parser_state != WSI_PARSING_COMPLETE) {
1364                         fprintf(stderr, "libwebsocket_client_handshake "
1365                                         "server response failed parsing\n");
1366                         goto bail3;
1367                 }
1368
1369                 /*
1370                  * 00 / 76 -->
1371                  *
1372                  * HTTP/1.1 101 WebSocket Protocol Handshake
1373                  * Upgrade: WebSocket
1374                  * Connection: Upgrade
1375                  * Sec-WebSocket-Origin: http://127.0.0.1
1376                  * Sec-WebSocket-Location: ws://127.0.0.1:9999/socket.io/websocket
1377                  *
1378                  * xxxxxxxxxxxxxxxx
1379                  */
1380
1381                 if (wsi->ietf_spec_revision == 0) {
1382                         if (!wsi->utf8_token[WSI_TOKEN_HTTP].token_len ||
1383                             !wsi->utf8_token[WSI_TOKEN_UPGRADE].token_len ||
1384                             !wsi->utf8_token[WSI_TOKEN_CHALLENGE].token_len ||
1385                             !wsi->utf8_token[WSI_TOKEN_CONNECTION].token_len ||
1386                             (!wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len &&
1387                             wsi->c_protocol != NULL)) {
1388                                 fprintf(stderr, "libwebsocket_client_handshake "
1389                                                 "missing required header(s)\n");
1390                                 pkt[len] = '\0';
1391                                 fprintf(stderr, "%s", pkt);
1392                                 goto bail3;
1393                         }
1394
1395                         strtolower(wsi->utf8_token[WSI_TOKEN_HTTP].token);
1396                         if (strcmp(wsi->utf8_token[WSI_TOKEN_HTTP].token,
1397                                 "101 websocket protocol handshake")) {
1398                                 fprintf(stderr, "libwebsocket_client_handshake "
1399                                         "server sent bad HTTP response '%s'\n",
1400                                         wsi->utf8_token[WSI_TOKEN_HTTP].token);
1401                                 goto bail3;
1402                         }
1403
1404                         if (wsi->utf8_token[WSI_TOKEN_CHALLENGE].token_len <
1405                                                                            16) {
1406                                 fprintf(stderr, "libwebsocket_client_handshake "
1407                                         "challenge reply too short %d\n",
1408                                         wsi->utf8_token[
1409                                                 WSI_TOKEN_CHALLENGE].token_len);
1410                                 pkt[len] = '\0';
1411                                 fprintf(stderr, "%s", pkt);
1412                                 goto bail3;
1413
1414                         }
1415
1416                         goto select_protocol;
1417                 }
1418
1419                 /*
1420                  * well, what the server sent looked reasonable for syntax.
1421                  * Now let's confirm it sent all the necessary headers
1422                  */
1423
1424                  if (!wsi->utf8_token[WSI_TOKEN_HTTP].token_len ||
1425                         !wsi->utf8_token[WSI_TOKEN_UPGRADE].token_len ||
1426                         !wsi->utf8_token[WSI_TOKEN_CONNECTION].token_len ||
1427                         !wsi->utf8_token[WSI_TOKEN_ACCEPT].token_len ||
1428                         (!wsi->utf8_token[WSI_TOKEN_NONCE].token_len &&
1429                                            wsi->ietf_spec_revision == 4) ||
1430                         (!wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len &&
1431                                                      wsi->c_protocol != NULL)) {
1432                         fprintf(stderr, "libwebsocket_client_handshake "
1433                                                 "missing required header(s)\n");
1434                         pkt[len] = '\0';
1435                         fprintf(stderr, "%s", pkt);
1436                         goto bail3;
1437                 }
1438
1439                 /*
1440                  * Everything seems to be there, now take a closer look at what
1441                  * is in each header
1442                  */
1443
1444                 strtolower(wsi->utf8_token[WSI_TOKEN_HTTP].token);
1445                 if (strcmp(wsi->utf8_token[WSI_TOKEN_HTTP].token,
1446                                                    "101 switching protocols")) {
1447                         fprintf(stderr, "libwebsocket_client_handshake "
1448                                         "server sent bad HTTP response '%s'\n",
1449                                          wsi->utf8_token[WSI_TOKEN_HTTP].token);
1450                         goto bail3;
1451                 }
1452
1453                 strtolower(wsi->utf8_token[WSI_TOKEN_UPGRADE].token);
1454                 if (strcmp(wsi->utf8_token[WSI_TOKEN_UPGRADE].token,
1455                                                                  "websocket")) {
1456                         fprintf(stderr, "libwebsocket_client_handshake server "
1457                                         "sent bad Upgrade header '%s'\n",
1458                                       wsi->utf8_token[WSI_TOKEN_UPGRADE].token);
1459                         goto bail3;
1460                 }
1461
1462                 strtolower(wsi->utf8_token[WSI_TOKEN_CONNECTION].token);
1463                 if (strcmp(wsi->utf8_token[WSI_TOKEN_CONNECTION].token,
1464                                                                    "upgrade")) {
1465                         fprintf(stderr, "libwebsocket_client_handshake server "
1466                                         "sent bad Connection hdr '%s'\n",
1467                                    wsi->utf8_token[WSI_TOKEN_CONNECTION].token);
1468                         goto bail3;
1469                 }
1470
1471 select_protocol:
1472                 pc = wsi->c_protocol;
1473
1474                 /*
1475                  * confirm the protocol the server wants to talk was in the list
1476                  * of protocols we offered
1477                  */
1478
1479                 if (!wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len) {
1480
1481                         /*
1482                          * no protocol name to work from,
1483                          * default to first protocol
1484                          */
1485                         wsi->protocol = &context->protocols[0];
1486
1487                         free(wsi->c_protocol);
1488
1489                         goto check_accept;
1490                 }
1491
1492                 while (*pc && !okay) {
1493                         if ((!strncmp(pc,
1494                                 wsi->utf8_token[WSI_TOKEN_PROTOCOL].token,
1495                            wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len)) &&
1496                  (pc[wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len] == ',' ||
1497                    pc[wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len] == '\0')) {
1498                                 okay = 1;
1499                                 continue;
1500                         }
1501                         while (*pc && *pc != ',')
1502                                 pc++;
1503                         while (*pc && *pc != ' ')
1504                                 pc++;
1505                 }
1506
1507                 /* done with him now */
1508
1509                 if (wsi->c_protocol)
1510                         free(wsi->c_protocol);
1511
1512
1513                 if (!okay) {
1514                         fprintf(stderr, "libwebsocket_client_handshake server "
1515                                                 "sent bad protocol '%s'\n",
1516                                      wsi->utf8_token[WSI_TOKEN_PROTOCOL].token);
1517                         goto bail2;
1518                 }
1519
1520                 /*
1521                  * identify the selected protocol struct and set it
1522                  */
1523                 n = 0;
1524                 wsi->protocol = NULL;
1525                 while (context->protocols[n].callback) {
1526                         if (strcmp(wsi->utf8_token[WSI_TOKEN_PROTOCOL].token,
1527                                                context->protocols[n].name) == 0)
1528                                 wsi->protocol = &context->protocols[n];
1529                         n++;
1530                 }
1531
1532                 if (wsi->protocol == NULL) {
1533                         fprintf(stderr, "libwebsocket_client_handshake server "
1534                                         "requested protocol '%s', which we "
1535                                         "said we supported but we don't!\n",
1536                                      wsi->utf8_token[WSI_TOKEN_PROTOCOL].token);
1537                         goto bail2;
1538                 }
1539
1540
1541                 /* instantiate the accepted extensions */
1542
1543                 if (!wsi->utf8_token[WSI_TOKEN_EXTENSIONS].token_len)
1544                         goto check_accept;
1545
1546                 /*
1547                  * break down the list of server accepted extensions
1548                  * and go through matching them or identifying bogons
1549                  */
1550
1551                 c = wsi->utf8_token[WSI_TOKEN_EXTENSIONS].token;
1552                 n = 0;
1553                 while (more) {
1554
1555                         if (*c && *c != ',') {
1556                                 ext_name[n] = *c++;
1557                                 if (n < sizeof(ext_name) - 1)
1558                                         n++;
1559                                 continue;
1560                         }
1561                         ext_name[n] = '\0';
1562                         if (!*c)
1563                                 more = 0;
1564
1565                         /* check we actually support it */
1566
1567                         n = 0;
1568                         ext = wsi->protocol->owning_server->extensions;
1569                         while (ext && ext->callback) {
1570
1571                                 if (strcmp(ext_name, ext->name)) {
1572                                         ext++;
1573                                         continue;
1574                                 }
1575
1576                                 n = 1;
1577
1578                                 /* instantiate the extension on this conn */
1579
1580                                 wsi->active_extensions_user[
1581                                         wsi->count_active_extensions] =
1582                                              malloc(ext->per_session_data_size);
1583                                 wsi->active_extensions[
1584                                           wsi->count_active_extensions] = ext;
1585
1586                                 /* allow him to construct his context */
1587
1588                                 ext->callback(wsi->protocol->owning_server,
1589                                         wsi, LWS_EXT_CALLBACK_CLIENT_CONSTRUCT,
1590                                                 wsi->active_extensions_user[
1591                                         wsi->count_active_extensions], NULL, 0);
1592
1593                                 wsi->count_active_extensions++;
1594
1595                                 ext++;
1596                         }
1597
1598                         if (n == 0) {
1599                                 fprintf(stderr, "Server said we should use"
1600                                       "an unknown extension '%s'!\n", ext_name);
1601                                 goto bail2;
1602                         }
1603
1604                         n = 0;
1605                 }
1606
1607
1608         check_accept:
1609
1610                 if (wsi->ietf_spec_revision == 0) {
1611
1612                         if (memcmp(wsi->initial_handshake_hash_base64,
1613                               wsi->utf8_token[WSI_TOKEN_CHALLENGE].token, 16)) {
1614                                 fprintf(stderr, "libwebsocket_client_handshake "
1615                                                "failed 00 challenge compare\n");
1616                                         pkt[len] = '\0';
1617                                         fprintf(stderr, "%s", pkt);
1618                                         goto bail2;
1619                         }
1620
1621                         goto accept_ok;
1622                 }
1623
1624                 /*
1625                  * Confirm his accept token is the one we precomputed
1626                  */
1627
1628                 if (strcmp(wsi->utf8_token[WSI_TOKEN_ACCEPT].token,
1629                                           wsi->initial_handshake_hash_base64)) {
1630                         fprintf(stderr, "libwebsocket_client_handshake server "
1631                                 "sent bad ACCEPT '%s' vs computed '%s'\n",
1632                                 wsi->utf8_token[WSI_TOKEN_ACCEPT].token,
1633                                             wsi->initial_handshake_hash_base64);
1634                         goto bail2;
1635                 }
1636
1637                 if (wsi->ietf_spec_revision == 4) {
1638                         /*
1639                          * Calculate the 04 masking key to use when
1640                          * sending data to server
1641                          */
1642
1643                         strcpy((char *)buf, wsi->key_b64);
1644                         p = (char *)buf + strlen(wsi->key_b64);
1645                         strcpy(p, wsi->utf8_token[WSI_TOKEN_NONCE].token);
1646                         p += wsi->utf8_token[WSI_TOKEN_NONCE].token_len;
1647                         strcpy(p, magic_websocket_04_masking_guid);
1648                         SHA1(buf, strlen((char *)buf), wsi->masking_key_04);
1649                 }
1650 accept_ok:
1651
1652                 /* allocate the per-connection user memory (if any) */
1653
1654                 if (wsi->protocol->per_session_data_size) {
1655                         wsi->user_space = malloc(
1656                                           wsi->protocol->per_session_data_size);
1657                         if (wsi->user_space  == NULL) {
1658                                 fprintf(stderr, "Out of memory for "
1659                                                            "conn user space\n");
1660                                 goto bail2;
1661                         }
1662                 } else
1663                         wsi->user_space = NULL;
1664
1665                 /* clear his proxy connection timeout */
1666
1667                 libwebsocket_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
1668
1669                 /* mark him as being alive */
1670
1671                 wsi->state = WSI_STATE_ESTABLISHED;
1672                 wsi->mode = LWS_CONNMODE_WS_CLIENT;
1673
1674                 fprintf(stderr, "handshake OK for protocol %s\n",
1675                                                            wsi->protocol->name);
1676
1677                 /* call him back to inform him he is up */
1678
1679                 wsi->protocol->callback(context, wsi,
1680                                  LWS_CALLBACK_CLIENT_ESTABLISHED,
1681                                  wsi->user_space,
1682                                  NULL, 0);
1683
1684                 break;
1685
1686 bail3:
1687                 if (wsi->c_protocol)
1688                         free(wsi->c_protocol);
1689
1690 bail2:
1691                 libwebsocket_close_and_free_session(context, wsi,
1692                                                      LWS_CLOSE_STATUS_NOSTATUS);
1693                 return 1;
1694
1695
1696         case LWS_CONNMODE_WS_SERVING:
1697         case LWS_CONNMODE_WS_CLIENT:
1698
1699                 /* handle session socket closed */
1700
1701                 if (pollfd->revents & (POLLERR | POLLHUP)) {
1702
1703                         fprintf(stderr, "Session Socket %p (fd=%d) dead\n",
1704                                 (void *)wsi, pollfd->fd);
1705
1706                         libwebsocket_close_and_free_session(context, wsi,
1707                                                      LWS_CLOSE_STATUS_NOSTATUS);
1708                         return 1;
1709                 }
1710
1711                 /* the guy requested a callback when it was OK to write */
1712
1713                 if ((pollfd->revents & POLLOUT) &&
1714                                             wsi->state == WSI_STATE_ESTABLISHED)
1715                         if (lws_handle_POLLOUT_event(context, wsi,
1716                                                                   pollfd) < 0) {
1717                                 libwebsocket_close_and_free_session(
1718                                          context, wsi, LWS_CLOSE_STATUS_NORMAL);
1719                                 return 1;
1720                         }
1721
1722
1723                 /* any incoming data ready? */
1724
1725                 if (!(pollfd->revents & POLLIN))
1726                         break;
1727
1728 #ifdef LWS_OPENSSL_SUPPORT
1729                 if (wsi->ssl)
1730                         eff_buf.token_len = SSL_read(wsi->ssl, buf, sizeof buf);
1731                 else
1732 #endif
1733                         eff_buf.token_len =
1734                                            recv(pollfd->fd, buf, sizeof buf, 0);
1735
1736                 if (eff_buf.token_len < 0) {
1737                         fprintf(stderr, "Socket read returned %d\n",
1738                                                             eff_buf.token_len);
1739                         break;
1740                 }
1741                 if (!eff_buf.token_len) {
1742                         libwebsocket_close_and_free_session(context, wsi,
1743                                                      LWS_CLOSE_STATUS_NOSTATUS);
1744                         return 1;
1745                 }
1746
1747                 /*
1748                  * give any active extensions a chance to munge the buffer
1749                  * before parse.  We pass in a pointer to an lws_tokens struct
1750                  * prepared with the default buffer and content length that's in
1751                  * there.  Rather than rewrite the default buffer, extensions
1752                  * that expect to grow the buffer can adapt .token to
1753                  * point to their own per-connection buffer in the extension
1754                  * user allocation.  By default with no extensions or no
1755                  * extension callback handling, just the normal input buffer is
1756                  * used then so it is efficient.
1757                  */
1758
1759                 eff_buf.token = (char *)buf;
1760
1761                 more = 1;
1762                 while (more) {
1763
1764                         more = 0;
1765
1766                         for (n = 0; n < wsi->count_active_extensions; n++) {
1767                                 m = wsi->active_extensions[n]->callback(context, wsi,
1768                                         LWS_EXT_CALLBACK_PACKET_RX_PREPARSE,
1769                                      wsi->active_extensions_user[n], &eff_buf, 0);
1770                                 if (m < 0) {
1771                                         fprintf(stderr, "Extension reports fatal error\n");
1772                                         libwebsocket_close_and_free_session(context, wsi,
1773                                                              LWS_CLOSE_STATUS_NOSTATUS);
1774                                         return 1;
1775                                 }
1776                                 if (m)
1777                                         more = 1;
1778                         }
1779
1780                         /* service incoming data */
1781
1782                         if (eff_buf.token_len) {
1783                                 n = libwebsocket_read(context, wsi,
1784                                      (unsigned char *)eff_buf.token, eff_buf.token_len);
1785                                 if (n < 0)
1786                                         /* we closed wsi */
1787                                         return 1;
1788                         }
1789
1790                         eff_buf.token = NULL;
1791                         eff_buf.token_len = 0;
1792                 }
1793                 break;
1794         }
1795
1796         return 0;
1797 }
1798
1799
1800 /**
1801  * libwebsocket_context_destroy() - Destroy the websocket context
1802  * @context:    Websocket context
1803  *
1804  *      This function closes any active connections and then frees the
1805  *      context.  After calling this, any further use of the context is
1806  *      undefined.
1807  */
1808 void
1809 libwebsocket_context_destroy(struct libwebsocket_context *context)
1810 {
1811         int n;
1812         int m;
1813         struct libwebsocket *wsi;
1814
1815         for (n = 0; n < FD_HASHTABLE_MODULUS; n++)
1816                 for (m = 0; m < context->fd_hashtable[n].length; m++) {
1817                         wsi = context->fd_hashtable[n].wsi[m];
1818                         libwebsocket_close_and_free_session(context, wsi,
1819                                                     LWS_CLOSE_STATUS_GOINGAWAY);
1820                 }
1821
1822 #ifdef WIN32
1823 #else
1824         close(context->fd_random);
1825 #endif
1826
1827 #ifdef LWS_OPENSSL_SUPPORT
1828         if (context->ssl_ctx)
1829                 SSL_CTX_free(context->ssl_ctx);
1830         if (context->ssl_client_ctx)
1831                 SSL_CTX_free(context->ssl_client_ctx);
1832 #endif
1833
1834         free(context);
1835
1836 #ifdef WIN32
1837         WSACleanup();
1838 #endif
1839 }
1840
1841 /**
1842  * libwebsocket_service() - Service any pending websocket activity
1843  * @context:    Websocket context
1844  * @timeout_ms: Timeout for poll; 0 means return immediately if nothing needed
1845  *              service otherwise block and service immediately, returning
1846  *              after the timeout if nothing needed service.
1847  *
1848  *      This function deals with any pending websocket traffic, for three
1849  *      kinds of event.  It handles these events on both server and client
1850  *      types of connection the same.
1851  *
1852  *      1) Accept new connections to our context's server
1853  *
1854  *      2) Perform pending broadcast writes initiated from other forked
1855  *         processes (effectively serializing asynchronous broadcasts)
1856  *
1857  *      3) Call the receive callback for incoming frame data received by
1858  *          server or client connections.
1859  *
1860  *      You need to call this service function periodically to all the above
1861  *      functions to happen; if your application is single-threaded you can
1862  *      just call it in your main event loop.
1863  *
1864  *      Alternatively you can fork a new process that asynchronously handles
1865  *      calling this service in a loop.  In that case you are happy if this
1866  *      call blocks your thread until it needs to take care of something and
1867  *      would call it with a large nonzero timeout.  Your loop then takes no
1868  *      CPU while there is nothing happening.
1869  *
1870  *      If you are calling it in a single-threaded app, you don't want it to
1871  *      wait around blocking other things in your loop from happening, so you
1872  *      would call it with a timeout_ms of 0, so it returns immediately if
1873  *      nothing is pending, or as soon as it services whatever was pending.
1874  */
1875
1876
1877 int
1878 libwebsocket_service(struct libwebsocket_context *context, int timeout_ms)
1879 {
1880         int n;
1881
1882         /* stay dead once we are dead */
1883
1884         if (context == NULL)
1885                 return 1;
1886
1887         /* wait for something to need service */
1888
1889         n = poll(context->fds, context->fds_count, timeout_ms);
1890         if (n == 0) /* poll timeout */
1891                 return 0;
1892
1893         if (n < 0) {
1894                 /*
1895                 fprintf(stderr, "Listen Socket dead\n");
1896                 */
1897                 return 1;
1898         }
1899
1900         /* handle accept on listening socket? */
1901
1902         for (n = 0; n < context->fds_count; n++)
1903                 if (context->fds[n].revents)
1904                         libwebsocket_service_fd(context, &context->fds[n]);
1905
1906         return 0;
1907 }
1908
1909 /**
1910  * libwebsocket_callback_on_writable() - Request a callback when this socket
1911  *                                       becomes able to be written to without
1912  *                                       blocking
1913  *
1914  * @context:    libwebsockets context
1915  * @wsi:        Websocket connection instance to get callback for
1916  */
1917
1918 int
1919 libwebsocket_callback_on_writable(struct libwebsocket_context *context,
1920                                                        struct libwebsocket *wsi)
1921 {
1922         int n;
1923
1924         for (n = 0; n < context->fds_count; n++)
1925                 if (context->fds[n].fd == wsi->sock) {
1926                         context->fds[n].events |= POLLOUT;
1927                         n = context->fds_count;
1928                 }
1929
1930         /* external POLL support via protocol 0 */
1931         context->protocols[0].callback(context, wsi,
1932                 LWS_CALLBACK_SET_MODE_POLL_FD,
1933                 (void *)(long)wsi->sock, NULL, POLLOUT);
1934
1935         return 1;
1936 }
1937
1938 /**
1939  * libwebsocket_callback_on_writable_all_protocol() - Request a callback for
1940  *                      all connections using the given protocol when it
1941  *                      becomes possible to write to each socket without
1942  *                      blocking in turn.
1943  *
1944  * @protocol:   Protocol whose connections will get callbacks
1945  */
1946
1947 int
1948 libwebsocket_callback_on_writable_all_protocol(
1949                                   const struct libwebsocket_protocols *protocol)
1950 {
1951         struct libwebsocket_context *context = protocol->owning_server;
1952         int n;
1953         int m;
1954         struct libwebsocket *wsi;
1955
1956         for (n = 0; n < FD_HASHTABLE_MODULUS; n++) {
1957
1958                 for (m = 0; m < context->fd_hashtable[n].length; m++) {
1959
1960                         wsi = context->fd_hashtable[n].wsi[m];
1961
1962                         if (wsi->protocol == protocol)
1963                                 libwebsocket_callback_on_writable(context, wsi);
1964                 }
1965         }
1966
1967         return 0;
1968 }
1969
1970 /**
1971  * libwebsocket_set_timeout() - marks the wsi as subject to a timeout
1972  *
1973  * You will not need this unless you are doing something special
1974  *
1975  * @wsi:        Websocket connection instance
1976  * @reason:     timeout reason
1977  * @secs:       how many seconds
1978  */
1979
1980 void
1981 libwebsocket_set_timeout(struct libwebsocket *wsi,
1982                                           enum pending_timeout reason, int secs)
1983 {
1984         struct timeval tv;
1985
1986         gettimeofday(&tv, NULL);
1987
1988         wsi->pending_timeout_limit = tv.tv_sec + secs;
1989         wsi->pending_timeout = reason;
1990 }
1991
1992
1993 /**
1994  * libwebsocket_get_socket_fd() - returns the socket file descriptor
1995  *
1996  * You will not need this unless you are doing something special
1997  *
1998  * @wsi:        Websocket connection instance
1999  */
2000
2001 int
2002 libwebsocket_get_socket_fd(struct libwebsocket *wsi)
2003 {
2004         return wsi->sock;
2005 }
2006
2007 /**
2008  * libwebsocket_rx_flow_control() - Enable and disable socket servicing for
2009  *                              receieved packets.
2010  *
2011  * If the output side of a server process becomes choked, this allows flow
2012  * control for the input side.
2013  *
2014  * @wsi:        Websocket connection instance to get callback for
2015  * @enable:     0 = disable read servicing for this connection, 1 = enable
2016  */
2017
2018 int
2019 libwebsocket_rx_flow_control(struct libwebsocket *wsi, int enable)
2020 {
2021         struct libwebsocket_context *context = wsi->protocol->owning_server;
2022         int n;
2023
2024         for (n = 0; n < context->fds_count; n++)
2025                 if (context->fds[n].fd == wsi->sock) {
2026                         if (enable)
2027                                 context->fds[n].events |= POLLIN;
2028                         else
2029                                 context->fds[n].events &= ~POLLIN;
2030
2031                         return 0;
2032                 }
2033
2034         if (enable)
2035                 /* external POLL support via protocol 0 */
2036                 context->protocols[0].callback(context, wsi,
2037                         LWS_CALLBACK_SET_MODE_POLL_FD,
2038                         (void *)(long)wsi->sock, NULL, POLLIN);
2039         else
2040                 /* external POLL support via protocol 0 */
2041                 context->protocols[0].callback(context, wsi,
2042                         LWS_CALLBACK_CLEAR_MODE_POLL_FD,
2043                         (void *)(long)wsi->sock, NULL, POLLIN);
2044
2045
2046         fprintf(stderr, "libwebsocket_callback_on_writable "
2047                                                      "unable to find socket\n");
2048         return 1;
2049 }
2050
2051 /**
2052  * libwebsocket_canonical_hostname() - returns this host's hostname
2053  *
2054  * This is typically used by client code to fill in the host parameter
2055  * when making a client connection.  You can only call it after the context
2056  * has been created.
2057  *
2058  * @context:    Websocket context
2059  */
2060
2061
2062 extern const char *
2063 libwebsocket_canonical_hostname(struct libwebsocket_context *context)
2064 {
2065         return (const char *)context->canonical_hostname;
2066 }
2067
2068
2069 static void sigpipe_handler(int x)
2070 {
2071 }
2072
2073 #ifdef LWS_OPENSSL_SUPPORT
2074 static int
2075 OpenSSL_verify_callback(int preverify_ok, X509_STORE_CTX *x509_ctx)
2076 {
2077
2078         SSL *ssl;
2079         int n;
2080         struct libwebsocket_context *context;
2081
2082         ssl = X509_STORE_CTX_get_ex_data(x509_ctx,
2083                 SSL_get_ex_data_X509_STORE_CTX_idx());
2084
2085         /*
2086          * !!! nasty openssl requires the index to come as a library-scope
2087          * static
2088          */
2089         context = SSL_get_ex_data(ssl, openssl_websocket_private_data_index);
2090
2091         n = context->protocols[0].callback(NULL, NULL,
2092                 LWS_CALLBACK_OPENSSL_PERFORM_CLIENT_CERT_VERIFICATION,
2093                                                    x509_ctx, ssl, preverify_ok);
2094
2095         /* convert return code from 0 = OK to 1 = OK */
2096
2097         if (!n)
2098                 n = 1;
2099         else
2100                 n = 0;
2101
2102         return n;
2103 }
2104 #endif
2105
2106
2107 /**
2108  * libwebsocket_create_context() - Create the websocket handler
2109  * @port:       Port to listen on... you can use 0 to suppress listening on
2110  *              any port, that's what you want if you are not running a
2111  *              websocket server at all but just using it as a client
2112  * @interf:  NULL to bind the listen socket to all interfaces, or the
2113  *              interface name, eg, "eth2"
2114  * @protocols:  Array of structures listing supported protocols and a protocol-
2115  *              specific callback for each one.  The list is ended with an
2116  *              entry that has a NULL callback pointer.
2117  *              It's not const because we write the owning_server member
2118  * @extensions: NULL or array of libwebsocket_extension structs listing the
2119  *              extensions this context supports
2120  * @ssl_cert_filepath:  If libwebsockets was compiled to use ssl, and you want
2121  *                      to listen using SSL, set to the filepath to fetch the
2122  *                      server cert from, otherwise NULL for unencrypted
2123  * @ssl_private_key_filepath: filepath to private key if wanting SSL mode,
2124  *                      else ignored
2125  * @gid:        group id to change to after setting listen socket, or -1.
2126  * @uid:        user id to change to after setting listen socket, or -1.
2127  * @options:    0, or LWS_SERVER_OPTION_DEFEAT_CLIENT_MASK
2128  *
2129  *      This function creates the listening socket and takes care
2130  *      of all initialization in one step.
2131  *
2132  *      After initialization, it returns a struct libwebsocket_context * that
2133  *      represents this server.  After calling, user code needs to take care
2134  *      of calling libwebsocket_service() with the context pointer to get the
2135  *      server's sockets serviced.  This can be done in the same process context
2136  *      or a forked process, or another thread,
2137  *
2138  *      The protocol callback functions are called for a handful of events
2139  *      including http requests coming in, websocket connections becoming
2140  *      established, and data arriving; it's also called periodically to allow
2141  *      async transmission.
2142  *
2143  *      HTTP requests are sent always to the FIRST protocol in @protocol, since
2144  *      at that time websocket protocol has not been negotiated.  Other
2145  *      protocols after the first one never see any HTTP callack activity.
2146  *
2147  *      The server created is a simple http server by default; part of the
2148  *      websocket standard is upgrading this http connection to a websocket one.
2149  *
2150  *      This allows the same server to provide files like scripts and favicon /
2151  *      images or whatever over http and dynamic data over websockets all in
2152  *      one place; they're all handled in the user callback.
2153  */
2154
2155 struct libwebsocket_context *
2156 libwebsocket_create_context(int port, const char *interf,
2157                                struct libwebsocket_protocols *protocols,
2158                                struct libwebsocket_extension *extensions,
2159                                const char *ssl_cert_filepath,
2160                                const char *ssl_private_key_filepath,
2161                                int gid, int uid, unsigned int options)
2162 {
2163         int n;
2164         int sockfd = 0;
2165         int fd;
2166         struct sockaddr_in serv_addr, cli_addr;
2167         int opt = 1;
2168         struct libwebsocket_context *context = NULL;
2169         unsigned int slen;
2170         char *p;
2171         char hostname[1024];
2172         struct hostent *he;
2173         struct libwebsocket *wsi;
2174
2175 #ifdef LWS_OPENSSL_SUPPORT
2176         SSL_METHOD *method;
2177         char ssl_err_buf[512];
2178 #endif
2179
2180 #ifdef _WIN32
2181         {
2182                 WORD wVersionRequested;
2183                 WSADATA wsaData;
2184                 int err;
2185
2186                 /* Use the MAKEWORD(lowbyte, highbyte) macro from Windef.h */
2187                 wVersionRequested = MAKEWORD(2, 2);
2188
2189                 err = WSAStartup(wVersionRequested, &wsaData);
2190                 if (err != 0) {
2191                         /* Tell the user that we could not find a usable */
2192                         /* Winsock DLL.                                  */
2193                         fprintf(stderr, "WSAStartup failed with error: %d\n",
2194                                                                            err);
2195                         return NULL;
2196                 }
2197         }
2198 #endif
2199
2200
2201         context = malloc(sizeof(struct libwebsocket_context));
2202         if (!context) {
2203                 fprintf(stderr, "No memory for websocket context\n");
2204                 return NULL;
2205         }
2206         context->protocols = protocols;
2207         context->listen_port = port;
2208         context->http_proxy_port = 0;
2209         context->http_proxy_address[0] = '\0';
2210         context->options = options;
2211         context->fds_count = 0;
2212         context->extensions = extensions;
2213
2214 #ifdef WIN32
2215         context->fd_random = 0;
2216 #else
2217         context->fd_random = open(SYSTEM_RANDOM_FILEPATH, O_RDONLY);
2218         if (context->fd_random < 0) {
2219                 fprintf(stderr, "Unable to open random device %s %d\n",
2220                                     SYSTEM_RANDOM_FILEPATH, context->fd_random);
2221                 return NULL;
2222         }
2223 #endif
2224
2225 #ifdef LWS_OPENSSL_SUPPORT
2226         context->use_ssl = 0;
2227         context->ssl_ctx = NULL;
2228         context->ssl_client_ctx = NULL;
2229         openssl_websocket_private_data_index = 0;
2230 #endif
2231         /* find canonical hostname */
2232
2233         hostname[(sizeof hostname) - 1] = '\0';
2234         gethostname(hostname, (sizeof hostname) - 1);
2235         he = gethostbyname(hostname);
2236         if (he) {
2237                 strncpy(context->canonical_hostname, he->h_name,
2238                                         sizeof context->canonical_hostname - 1);
2239                 context->canonical_hostname[
2240                                 sizeof context->canonical_hostname - 1] = '\0';
2241         } else
2242                 strncpy(context->canonical_hostname, hostname,
2243                                         sizeof context->canonical_hostname - 1);
2244
2245         /* split the proxy ads:port if given */
2246
2247         p = getenv("http_proxy");
2248         if (p) {
2249                 strncpy(context->http_proxy_address, p,
2250                                         sizeof context->http_proxy_address - 1);
2251                 context->http_proxy_address[
2252                                  sizeof context->http_proxy_address - 1] = '\0';
2253
2254                 p = strchr(context->http_proxy_address, ':');
2255                 if (p == NULL) {
2256                         fprintf(stderr, "http_proxy needs to be ads:port\n");
2257                         return NULL;
2258                 }
2259                 *p = '\0';
2260                 context->http_proxy_port = atoi(p + 1);
2261
2262                 fprintf(stderr, "Using proxy %s:%u\n",
2263                                 context->http_proxy_address,
2264                                                       context->http_proxy_port);
2265         }
2266
2267         if (port) {
2268
2269 #ifdef LWS_OPENSSL_SUPPORT
2270                 context->use_ssl = ssl_cert_filepath != NULL &&
2271                                                ssl_private_key_filepath != NULL;
2272                 if (context->use_ssl)
2273                         fprintf(stderr, " Compiled with SSL support, "
2274                                                                   "using it\n");
2275                 else
2276                         fprintf(stderr, " Compiled with SSL support, "
2277                                                               "not using it\n");
2278
2279 #else
2280                 if (ssl_cert_filepath != NULL &&
2281                                              ssl_private_key_filepath != NULL) {
2282                         fprintf(stderr, " Not compiled for OpenSSl support!\n");
2283                         return NULL;
2284                 }
2285                 fprintf(stderr, " Compiled without SSL support, "
2286                                                        "serving unencrypted\n");
2287 #endif
2288         }
2289
2290         /* ignore SIGPIPE */
2291 #ifdef WIN32
2292 #else
2293         signal(SIGPIPE, sigpipe_handler);
2294 #endif
2295
2296
2297 #ifdef LWS_OPENSSL_SUPPORT
2298
2299         /* basic openssl init */
2300
2301         SSL_library_init();
2302
2303         OpenSSL_add_all_algorithms();
2304         SSL_load_error_strings();
2305
2306         openssl_websocket_private_data_index =
2307                 SSL_get_ex_new_index(0, "libwebsockets", NULL, NULL, NULL);
2308
2309         /*
2310          * Firefox insists on SSLv23 not SSLv3
2311          * Konq disables SSLv2 by default now, SSLv23 works
2312          */
2313
2314         method = (SSL_METHOD *)SSLv23_server_method();
2315         if (!method) {
2316                 fprintf(stderr, "problem creating ssl method: %s\n",
2317                         ERR_error_string(ERR_get_error(), ssl_err_buf));
2318                 return NULL;
2319         }
2320         context->ssl_ctx = SSL_CTX_new(method); /* create context */
2321         if (!context->ssl_ctx) {
2322                 fprintf(stderr, "problem creating ssl context: %s\n",
2323                         ERR_error_string(ERR_get_error(), ssl_err_buf));
2324                 return NULL;
2325         }
2326
2327         /* client context */
2328         if (port == CONTEXT_PORT_NO_LISTEN)
2329         {
2330                 method = (SSL_METHOD *)SSLv23_client_method();
2331                 if (!method) {
2332                         fprintf(stderr, "problem creating ssl method: %s\n",
2333                                 ERR_error_string(ERR_get_error(), ssl_err_buf));
2334                         return NULL;
2335                 }
2336                 /* create context */
2337                 context->ssl_client_ctx = SSL_CTX_new(method);
2338                 if (!context->ssl_client_ctx) {
2339                         fprintf(stderr, "problem creating ssl context: %s\n",
2340                                 ERR_error_string(ERR_get_error(), ssl_err_buf));
2341                         return NULL;
2342                 }
2343
2344                 /* openssl init for cert verification (for client sockets) */
2345
2346                 if (!SSL_CTX_load_verify_locations(
2347                                         context->ssl_client_ctx, NULL,
2348                                                       LWS_OPENSSL_CLIENT_CERTS))
2349                         fprintf(stderr,
2350                             "Unable to load SSL Client certs from %s "
2351                             "(set by --with-client-cert-dir= in configure) -- "
2352                                 " client ssl isn't going to work",
2353                                                       LWS_OPENSSL_CLIENT_CERTS);
2354
2355                 /*
2356                  * callback allowing user code to load extra verification certs
2357                  * helping the client to verify server identity
2358                  */
2359
2360                 context->protocols[0].callback(context, NULL,
2361                         LWS_CALLBACK_OPENSSL_LOAD_EXTRA_CLIENT_VERIFY_CERTS,
2362                         context->ssl_client_ctx, NULL, 0);
2363         }
2364         /* as a server, are we requiring clients to identify themselves? */
2365
2366         if (options & LWS_SERVER_OPTION_REQUIRE_VALID_OPENSSL_CLIENT_CERT) {
2367
2368                 /* absolutely require the client cert */
2369
2370                 SSL_CTX_set_verify(context->ssl_ctx,
2371                        SSL_VERIFY_PEER | SSL_VERIFY_FAIL_IF_NO_PEER_CERT,
2372                                                        OpenSSL_verify_callback);
2373
2374                 /*
2375                  * give user code a chance to load certs into the server
2376                  * allowing it to verify incoming client certs
2377                  */
2378
2379                 context->protocols[0].callback(context, NULL,
2380                         LWS_CALLBACK_OPENSSL_LOAD_EXTRA_SERVER_VERIFY_CERTS,
2381                                                      context->ssl_ctx, NULL, 0);
2382         }
2383
2384         if (context->use_ssl) {
2385
2386                 /* openssl init for server sockets */
2387
2388                 /* set the local certificate from CertFile */
2389                 n = SSL_CTX_use_certificate_file(context->ssl_ctx,
2390                                         ssl_cert_filepath, SSL_FILETYPE_PEM);
2391                 if (n != 1) {
2392                         fprintf(stderr, "problem getting cert '%s': %s\n",
2393                                 ssl_cert_filepath,
2394                                 ERR_error_string(ERR_get_error(), ssl_err_buf));
2395                         return NULL;
2396                 }
2397                 /* set the private key from KeyFile */
2398                 if (SSL_CTX_use_PrivateKey_file(context->ssl_ctx,
2399                              ssl_private_key_filepath, SSL_FILETYPE_PEM) != 1) {
2400                         fprintf(stderr, "ssl problem getting key '%s': %s\n",
2401                                                 ssl_private_key_filepath,
2402                                 ERR_error_string(ERR_get_error(), ssl_err_buf));
2403                         return NULL;
2404                 }
2405                 /* verify private key */
2406                 if (!SSL_CTX_check_private_key(context->ssl_ctx)) {
2407                         fprintf(stderr, "Private SSL key doesn't match cert\n");
2408                         return NULL;
2409                 }
2410
2411                 /* SSL is happy and has a cert it's content with */
2412         }
2413 #endif
2414
2415         /* selftest */
2416
2417         if (lws_b64_selftest())
2418                 return NULL;
2419
2420         /* fd hashtable init */
2421
2422         for (n = 0; n < FD_HASHTABLE_MODULUS; n++)
2423                 context->fd_hashtable[n].length = 0;
2424
2425         /* set up our external listening socket we serve on */
2426
2427         if (port) {
2428
2429                 sockfd = socket(AF_INET, SOCK_STREAM, 0);
2430                 if (sockfd < 0) {
2431                         fprintf(stderr, "ERROR opening socket");
2432                         return NULL;
2433                 }
2434
2435                 /* allow us to restart even if old sockets in TIME_WAIT */
2436                 setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt));
2437
2438
2439                 /* Disable Nagle */
2440                 opt = 1;
2441                 setsockopt(sockfd, SOL_TCP, TCP_NODELAY, &opt, sizeof(opt));
2442
2443                 bzero((char *) &serv_addr, sizeof(serv_addr));
2444                 serv_addr.sin_family = AF_INET;
2445                 if (interf == NULL)
2446                         serv_addr.sin_addr.s_addr = INADDR_ANY;
2447                 else
2448                         interface_to_sa(interf, &serv_addr,
2449                                                 sizeof(serv_addr));
2450                 serv_addr.sin_port = htons(port);
2451
2452                 n = bind(sockfd, (struct sockaddr *) &serv_addr,
2453                                                              sizeof(serv_addr));
2454                 if (n < 0) {
2455                         fprintf(stderr, "ERROR on binding to port %d (%d %d)\n",
2456                                                                 port, n, errno);
2457                         return NULL;
2458                 }
2459
2460                 wsi = malloc(sizeof(struct libwebsocket));
2461                 memset(wsi, 0, sizeof (struct libwebsocket));
2462                 wsi->sock = sockfd;
2463                 wsi->count_active_extensions = 0;
2464                 wsi->mode = LWS_CONNMODE_SERVER_LISTENER;
2465                 insert_wsi(context, wsi);
2466
2467                 listen(sockfd, 5);
2468                 fprintf(stderr, " Listening on port %d\n", port);
2469
2470                 /* list in the internal poll array */
2471
2472                 context->fds[context->fds_count].fd = sockfd;
2473                 context->fds[context->fds_count++].events = POLLIN;
2474
2475                 /* external POLL support via protocol 0 */
2476                 context->protocols[0].callback(context, wsi,
2477                         LWS_CALLBACK_ADD_POLL_FD,
2478                         (void *)(long)sockfd, NULL, POLLIN);
2479
2480         }
2481
2482         /* drop any root privs for this process */
2483 #ifdef WIN32
2484 #else
2485         if (gid != -1)
2486                 if (setgid(gid))
2487                         fprintf(stderr, "setgid: %s\n", strerror(errno));
2488         if (uid != -1)
2489                 if (setuid(uid))
2490                         fprintf(stderr, "setuid: %s\n", strerror(errno));
2491 #endif
2492
2493         /* set up our internal broadcast trigger sockets per-protocol */
2494
2495         for (context->count_protocols = 0;
2496                         protocols[context->count_protocols].callback;
2497                                                    context->count_protocols++) {
2498                 protocols[context->count_protocols].owning_server = context;
2499                 protocols[context->count_protocols].protocol_index =
2500                                                        context->count_protocols;
2501
2502                 fd = socket(AF_INET, SOCK_STREAM, 0);
2503                 if (fd < 0) {
2504                         fprintf(stderr, "ERROR opening socket");
2505                         return NULL;
2506                 }
2507
2508                 /* allow us to restart even if old sockets in TIME_WAIT */
2509                 setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt));
2510
2511                 bzero((char *) &serv_addr, sizeof(serv_addr));
2512                 serv_addr.sin_family = AF_INET;
2513                 serv_addr.sin_addr.s_addr = inet_addr("127.0.0.1");
2514                 serv_addr.sin_port = 0; /* pick the port for us */
2515
2516                 n = bind(fd, (struct sockaddr *) &serv_addr, sizeof(serv_addr));
2517                 if (n < 0) {
2518                         fprintf(stderr, "ERROR on binding to port %d (%d %d)\n",
2519                                                                 port, n, errno);
2520                         return NULL;
2521                 }
2522
2523                 slen = sizeof cli_addr;
2524                 n = getsockname(fd, (struct sockaddr *)&cli_addr, &slen);
2525                 if (n < 0) {
2526                         fprintf(stderr, "getsockname failed\n");
2527                         return NULL;
2528                 }
2529                 protocols[context->count_protocols].broadcast_socket_port =
2530                                                        ntohs(cli_addr.sin_port);
2531                 listen(fd, 5);
2532
2533                 debug("  Protocol %s broadcast socket %d\n",
2534                                 protocols[context->count_protocols].name,
2535                                                       ntohs(cli_addr.sin_port));
2536
2537                 /* dummy wsi per broadcast proxy socket */
2538
2539                 wsi = malloc(sizeof(struct libwebsocket));
2540                 memset(wsi, 0, sizeof (struct libwebsocket));
2541                 wsi->sock = fd;
2542                 wsi->mode = LWS_CONNMODE_BROADCAST_PROXY_LISTENER;
2543                 wsi->count_active_extensions = 0;
2544                 /* note which protocol we are proxying */
2545                 wsi->protocol_index_for_broadcast_proxy =
2546                                                        context->count_protocols;
2547                 insert_wsi(context, wsi);
2548
2549                 /* list in internal poll array */
2550
2551                 context->fds[context->fds_count].fd = fd;
2552                 context->fds[context->fds_count].events = POLLIN;
2553                 context->fds[context->fds_count].revents = 0;
2554                 context->fds_count++;
2555
2556                 /* external POLL support via protocol 0 */
2557                 context->protocols[0].callback(context, wsi,
2558                         LWS_CALLBACK_ADD_POLL_FD,
2559                         (void *)(long)fd, NULL, POLLIN);
2560         }
2561
2562         return context;
2563 }
2564
2565
2566 #ifndef LWS_NO_FORK
2567
2568 /**
2569  * libwebsockets_fork_service_loop() - Optional helper function forks off
2570  *                                a process for the websocket server loop.
2571  *                              You don't have to use this but if not, you
2572  *                              have to make sure you are calling
2573  *                              libwebsocket_service periodically to service
2574  *                              the websocket traffic
2575  * @context:    server context returned by creation function
2576  */
2577
2578 int
2579 libwebsockets_fork_service_loop(struct libwebsocket_context *context)
2580 {
2581         int fd;
2582         struct sockaddr_in cli_addr;
2583         int n;
2584         int p;
2585
2586         n = fork();
2587         if (n < 0)
2588                 return n;
2589
2590         if (!n) {
2591
2592                 /* main process context */
2593
2594                 /*
2595                  * set up the proxy sockets to allow broadcast from
2596                  * service process context
2597                  */
2598
2599                 for (p = 0; p < context->count_protocols; p++) {
2600                         fd = socket(AF_INET, SOCK_STREAM, 0);
2601                         if (fd < 0) {
2602                                 fprintf(stderr, "Unable to create socket\n");
2603                                 return -1;
2604                         }
2605                         cli_addr.sin_family = AF_INET;
2606                         cli_addr.sin_port = htons(
2607                              context->protocols[p].broadcast_socket_port);
2608                         cli_addr.sin_addr.s_addr = inet_addr("127.0.0.1");
2609                         n = connect(fd, (struct sockaddr *)&cli_addr,
2610                                                                sizeof cli_addr);
2611                         if (n < 0) {
2612                                 fprintf(stderr, "Unable to connect to "
2613                                                 "broadcast socket %d, %s\n",
2614                                                 n, strerror(errno));
2615                                 return -1;
2616                         }
2617
2618                         context->protocols[p].broadcast_socket_user_fd = fd;
2619                 }
2620
2621                 return 0;
2622         }
2623
2624         /* we want a SIGHUP when our parent goes down */
2625         prctl(PR_SET_PDEATHSIG, SIGHUP);
2626
2627         /* in this forked process, sit and service websocket connections */
2628
2629         while (1)
2630                 if (libwebsocket_service(context, 1000))
2631                         return -1;
2632
2633         return 0;
2634 }
2635
2636 #endif
2637
2638 /**
2639  * libwebsockets_get_protocol() - Returns a protocol pointer from a websocket
2640  *                                connection.
2641  * @wsi:        pointer to struct websocket you want to know the protocol of
2642  *
2643  *
2644  *      This is useful to get the protocol to broadcast back to from inside
2645  * the callback.
2646  */
2647
2648 const struct libwebsocket_protocols *
2649 libwebsockets_get_protocol(struct libwebsocket *wsi)
2650 {
2651         return wsi->protocol;
2652 }
2653
2654 /**
2655  * libwebsockets_broadcast() - Sends a buffer to the callback for all active
2656  *                                connections of the given protocol.
2657  * @protocol:   pointer to the protocol you will broadcast to all members of
2658  * @buf:  buffer containing the data to be broadcase.  NOTE: this has to be
2659  *              allocated with LWS_SEND_BUFFER_PRE_PADDING valid bytes before
2660  *              the pointer and LWS_SEND_BUFFER_POST_PADDING afterwards in the
2661  *              case you are calling this function from callback context.
2662  * @len:        length of payload data in buf, starting from buf.
2663  *
2664  *      This function allows bulk sending of a packet to every connection using
2665  * the given protocol.  It does not send the data directly; instead it calls
2666  * the callback with a reason type of LWS_CALLBACK_BROADCAST.  If the callback
2667  * wants to actually send the data for that connection, the callback itself
2668  * should call libwebsocket_write().
2669  *
2670  * libwebsockets_broadcast() can be called from another fork context without
2671  * having to take any care about data visibility between the processes, it'll
2672  * "just work".
2673  */
2674
2675
2676 int
2677 libwebsockets_broadcast(const struct libwebsocket_protocols *protocol,
2678                                                  unsigned char *buf, size_t len)
2679 {
2680         struct libwebsocket_context *context = protocol->owning_server;
2681         int n;
2682         int m;
2683         struct libwebsocket * wsi;
2684
2685         if (!protocol->broadcast_socket_user_fd) {
2686                 /*
2687                  * We are either running unforked / flat, or we are being
2688                  * called from poll thread context
2689                  * eg, from a callback.  In that case don't use sockets for
2690                  * broadcast IPC (since we can't open a socket connection to
2691                  * a socket listening on our own thread) but directly do the
2692                  * send action.
2693                  *
2694                  * Locking is not needed because we are by definition being
2695                  * called in the poll thread context and are serialized.
2696                  */
2697
2698                 for (n = 0; n < FD_HASHTABLE_MODULUS; n++) {
2699
2700                         for (m = 0; m < context->fd_hashtable[n].length; m++) {
2701
2702                                 wsi = context->fd_hashtable[n].wsi[m];
2703
2704                                 if (wsi->mode != LWS_CONNMODE_WS_SERVING)
2705                                         continue;
2706
2707                                 /*
2708                                  * never broadcast to
2709                                  * non-established connections
2710                                  */
2711                                 if (wsi->state != WSI_STATE_ESTABLISHED)
2712                                         continue;
2713
2714                                 /* only broadcast to guys using
2715                                  * requested protocol
2716                                  */
2717                                 if (wsi->protocol != protocol)
2718                                         continue;
2719
2720                                 wsi->protocol->callback(context, wsi,
2721                                          LWS_CALLBACK_BROADCAST,
2722                                          wsi->user_space,
2723                                          buf, len);
2724                         }
2725                 }
2726
2727                 return 0;
2728         }
2729
2730         /*
2731          * We're being called from a different process context than the server
2732          * loop.  Instead of broadcasting directly, we send our
2733          * payload on a socket to do the IPC; the server process will serialize
2734          * the broadcast action in its main poll() loop.
2735          *
2736          * There's one broadcast socket listening for each protocol supported
2737          * set up when the websocket server initializes
2738          */
2739
2740         n = send(protocol->broadcast_socket_user_fd, buf, len, MSG_NOSIGNAL);
2741
2742         return n;
2743 }
2744
2745 int
2746 libwebsocket_is_final_fragment(struct libwebsocket *wsi)
2747 {
2748         return wsi->final;
2749 }