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,
 186                                         wsi->active_extensions[n], wsi,
 187                                         LWS_EXT_CALLBACK_FLUSH_PENDING_TX,
 188                                    wsi->active_extensions_user[n], &eff_buf, 0);
 189                         if (m < 0) {
 190                                 fprintf(stderr, "Extension reports "
 191                                                                "fatal error\n");
 192                                 goto just_kill_connection;
 193                         }
 194                         if (m)
 195                                 /*
 196                                  * at least one extension told us he has more
 197                                  * to spill, so we will go around again after
 198                                  */
 199                                 ret = 1;
 200                 }
 201
 202                 /* assuming they left us something to send, send it */
 203
 204                 if (eff_buf.token_len)
 205                         if (lws_issue_raw(wsi, (unsigned char *)eff_buf.token,
 206                                                              eff_buf.token_len))
 207                                 goto just_kill_connection;
 208         }
 209
 210         /*
 211          * signal we are closing, libsocket_write will
 212          * add any necessary version-specific stuff.  If the write fails,
 213          * no worries we are closing anyway.  If we didn't initiate this
 214          * close, then our state has been changed to
 215          * WSI_STATE_RETURNED_CLOSE_ALREADY and we will skip this.
 216          *
 217          * Likewise if it's a second call to close this connection after we
 218          * sent the close indication to the peer already, we are in state
 219          * WSI_STATE_AWAITING_CLOSE_ACK and will skip doing this a second time.
 220          */
 221
 222         if (old_state == WSI_STATE_ESTABLISHED &&
 223                                           reason != LWS_CLOSE_STATUS_NOSTATUS) {
 224                 n = libwebsocket_write(wsi, &buf[LWS_SEND_BUFFER_PRE_PADDING],
 225                                                             0, LWS_WRITE_CLOSE);
 226                 if (!n) {
 227                         /*
 228                          * we have sent a nice protocol level indication we
 229                          * now wish to close, we should not send anything more
 230                          */
 231
 232                         wsi->state = WSI_STATE_AWAITING_CLOSE_ACK;
 233
 234                         /* and we should wait for a reply for a bit */
 235
 236                         libwebsocket_set_timeout(wsi,
 237                                                   PENDING_TIMEOUT_CLOSE_ACK, 5);
 238
 239                         fprintf(stderr, "sent close indication, awaiting ack\n");
 240
 241                         return;
 242                 }
 243
 244                 /* else, the send failed and we should just hang up */
 245         }
 246
 247 just_kill_connection:
 248         /*
 249          * we won't be servicing or receiving anything further from this guy
 250          * remove this fd from wsi mapping hashtable
 251          */
 252
 253         delete_from_fd(context, wsi->sock);
 254
 255         /* delete it from the internal poll list if still present */
 256
 257         for (n = 0; n < context->fds_count; n++) {
 258                 if (context->fds[n].fd != wsi->sock)
 259                         continue;
 260                 while (n < context->fds_count - 1) {
 261                         context->fds[n] = context->fds[n + 1];
 262                         n++;
 263                 }
 264                 context->fds_count--;
 265                 /* we only have to deal with one */
 266                 n = context->fds_count;
 267         }
 268
 269         /* remove also from external POLL support via protocol 0 */
 270
 271         context->protocols[0].callback(context, wsi,
 272                     LWS_CALLBACK_DEL_POLL_FD, (void *)(long)wsi->sock, NULL, 0);
 273
 274         wsi->state = WSI_STATE_DEAD_SOCKET;
 275
 276         /* tell the user it's all over for this guy */
 277
 278         if (wsi->protocol && wsi->protocol->callback &&
 279                                              old_state == WSI_STATE_ESTABLISHED)
 280                 wsi->protocol->callback(context, wsi, LWS_CALLBACK_CLOSED,
 281                                                       wsi->user_space, NULL, 0);
 282
 283         /* deallocate any active extension contexts */
 284
 285         for (n = 0; n < wsi->count_active_extensions; n++) {
 286                 if (!wsi->active_extensions[n]->callback)
 287                         continue;
 288
 289                 wsi->active_extensions[n]->callback(context,
 290                         wsi->active_extensions[n], wsi,
 291                                 LWS_EXT_CALLBACK_DESTROY,
 292                                        wsi->active_extensions_user[n], NULL, 0);
 293
 294                 free(wsi->active_extensions_user[n]);
 295         }
 296
 297         /* free up his parsing allocations */
 298
 299         for (n = 0; n < WSI_TOKEN_COUNT; n++)
 300                 if (wsi->utf8_token[n].token)
 301                         free(wsi->utf8_token[n].token);
 302
 303 /*      fprintf(stderr, "closing fd=%d\n", wsi->sock); */
 304
 305 #ifdef LWS_OPENSSL_SUPPORT
 306         if (wsi->ssl) {
 307                 n = SSL_get_fd(wsi->ssl);
 308                 SSL_shutdown(wsi->ssl);
 309 #ifdef WIN32
 310                 closesocket(n);
 311 #else
 312                 close(n);
 313 #endif
 314                 SSL_free(wsi->ssl);
 315         } else {
 316 #endif
 317                 shutdown(wsi->sock, SHUT_RDWR);
 318 #ifdef WIN32
 319                 closesocket(wsi->sock);
 320 #else
 321                 close(wsi->sock);
 322 #endif
 323 #ifdef LWS_OPENSSL_SUPPORT
 324         }
 325 #endif
 326         if (wsi->user_space)
 327                 free(wsi->user_space);
 328
 329         free(wsi);
 330 }
 331
 332 /**
 333  * libwebsockets_hangup_on_client() - Server calls to terminate client
 334  *                                      connection
 335  * @context:    libwebsockets context
 336  * @fd:         Connection socket descriptor
 337  */
 338
 339 void
 340 libwebsockets_hangup_on_client(struct libwebsocket_context *context, int fd)
 341 {
 342         struct libwebsocket *wsi = wsi_from_fd(context, fd);
 343
 344         if (wsi == NULL)
 345                 return;
 346
 347         libwebsocket_close_and_free_session(context, wsi,
 348                                                      LWS_CLOSE_STATUS_NOSTATUS);
 349 }
 350
 351
 352 /**
 353  * libwebsockets_get_peer_addresses() - Get client address information
 354  * @fd:         Connection socket descriptor
 355  * @name:       Buffer to take client address name
 356  * @name_len:   Length of client address name buffer
 357  * @rip:        Buffer to take client address IP qotted quad
 358  * @rip_len:    Length of client address IP buffer
 359  *
 360  *      This function fills in @name and @rip with the name and IP of
 361  *      the client connected with socket descriptor @fd.  Names may be
 362  *      truncated if there is not enough room.  If either cannot be
 363  *      determined, they will be returned as valid zero-length strings.
 364  */
 365
 366 void
 367 libwebsockets_get_peer_addresses(int fd, char *name, int name_len,
 368                                         char *rip, int rip_len)
 369 {
 370         unsigned int len;
 371         struct sockaddr_in sin;
 372         struct hostent *host;
 373         struct hostent *host1;
 374         char ip[128];
 375         unsigned char *p;
 376         int n;
 377         struct sockaddr_un *un;
 378
 379         rip[0] = '\0';
 380         name[0] = '\0';
 381
 382         len = sizeof sin;
 383         if (getpeername(fd, (struct sockaddr *) &sin, &len) < 0) {
 384                 perror("getpeername");
 385                 return;
 386         }
 387
 388         host = gethostbyaddr((char *) &sin.sin_addr, sizeof sin.sin_addr,
 389                                                                        AF_INET);
 390         if (host == NULL) {
 391                 perror("gethostbyaddr");
 392                 return;
 393         }
 394
 395         strncpy(name, host->h_name, name_len);
 396         name[name_len - 1] = '\0';
 397
 398         host1 = gethostbyname(host->h_name);
 399         if (host1 == NULL)
 400                 return;
 401         p = (unsigned char *)host1;
 402         n = 0;
 403         while (p != NULL) {
 404                 p = (unsigned char *)host1->h_addr_list[n++];
 405                 if (p == NULL)
 406                         continue;
 407                 if ((host1->h_addrtype != AF_INET)
 408 #ifdef AF_LOCAL
 409                         && (host1->h_addrtype != AF_LOCAL)
 410 #endif
 411                         )
 412                         continue;
 413
 414                 if (host1->h_addrtype == AF_INET)
 415                         sprintf(ip, "%u.%u.%u.%u", p[0], p[1], p[2], p[3]);
 416 #ifdef AF_LOCAL
 417                 else {
 418                         un = (struct sockaddr_un *)p;
 419                         strncpy(ip, un->sun_path, sizeof(ip) -1);
 420                         ip[sizeof(ip) - 1] = '\0';
 421                 }
 422 #endif
 423                 p = NULL;
 424                 strncpy(rip, ip, rip_len);
 425                 rip[rip_len - 1] = '\0';
 426         }
 427 }
 428
 429 int libwebsockets_get_random(struct libwebsocket_context *context,
 430                                                              void *buf, int len)
 431 {
 432         int n;
 433         char *p = buf;
 434
 435 #ifdef WIN32
 436         for (n = 0; n < len; n++)
 437                 p[n] = (unsigned char)rand();
 438 #else
 439         n = read(context->fd_random, p, len);
 440 #endif
 441
 442         return n;
 443 }
 444
 445 unsigned char *
 446 libwebsockets_SHA1(const unsigned char *d, size_t n, unsigned char *md)
 447 {
 448         return SHA1(d, n, md);
 449 }
 450
 451 void libwebsockets_00_spaceout(char *key, int spaces, int seed)
 452 {
 453         char *p;
 454
 455         key++;
 456         while (spaces--) {
 457                 if (*key && (seed & 1))
 458                         key++;
 459                 seed >>= 1;
 460
 461                 p = key + strlen(key);
 462                 while (p >= key) {
 463                         p[1] = p[0];
 464                         p--;
 465                 }
 466                 *key++ = ' ';
 467         }
 468 }
 469
 470 void libwebsockets_00_spam(char *key, int count, int seed)
 471 {
 472         char *p;
 473
 474         key++;
 475         while (count--) {
 476
 477                 if (*key && (seed & 1))
 478                         key++;
 479                 seed >>= 1;
 480
 481                 p = key + strlen(key);
 482                 while (p >= key) {
 483                         p[1] = p[0];
 484                         p--;
 485                 }
 486                 *key++ = 0x21 + ((seed & 0xffff) % 15);
 487                 /* 4 would use it up too fast.. not like it matters */
 488                 seed >>= 1;
 489         }
 490 }
 491
 492 int lws_send_pipe_choked(struct libwebsocket *wsi)
 493 {
 494         struct pollfd fds;
 495
 496         fds.fd = wsi->sock;
 497         fds.events = POLLOUT;
 498         fds.revents = 0;
 499
 500         if (poll(&fds, 1, 0) != 1)
 501                 return 1;
 502
 503         if ((fds.revents & POLLOUT) == 0)
 504                 return 1;
 505
 506         /* okay to send another packet without blocking */
 507
 508         return 0;
 509 }
 510
 511 static int
 512 lws_handle_POLLOUT_event(struct libwebsocket_context *context,
 513                                 struct libwebsocket *wsi, struct pollfd *pollfd)
 514 {
 515         struct lws_tokens eff_buf;
 516         int n;
 517         int ret;
 518         int m;
 519
 520         if (!wsi->extension_data_pending)
 521                 goto user_service;
 522
 523         /*
 524          * check in on the active extensions, see if they
 525          * had pending stuff to spill... they need to get the
 526          * first look-in otherwise sequence will be disordered
 527          *
 528          * NULL, zero-length eff_buf means just spill pending
 529          */
 530
 531         ret = 1;
 532         while (ret == 1) {
 533
 534                 /* default to nobody has more to spill */
 535
 536                 ret = 0;
 537                 eff_buf.token = NULL;
 538                 eff_buf.token_len = 0;
 539
 540                 /* give every extension a chance to spill */
 541
 542                 for (n = 0; n < wsi->count_active_extensions; n++) {
 543                         m = wsi->active_extensions[n]->callback(
 544                                 wsi->protocol->owning_server,
 545                                 wsi->active_extensions[n], wsi,
 546                                         LWS_EXT_CALLBACK_PACKET_TX_PRESEND,
 547                                    wsi->active_extensions_user[n], &eff_buf, 0);
 548                         if (m < 0) {
 549                                 fprintf(stderr, "extension reports fatal error\n");
 550                                 return -1;
 551                         }
 552                         if (m)
 553                                 /*
 554                                  * at least one extension told us he has more
 555                                  * to spill, so we will go around again after
 556                                  */
 557                                 ret = 1;
 558                 }
 559
 560                 /* assuming they gave us something to send, send it */
 561
 562                 if (eff_buf.token_len) {
 563                         if (lws_issue_raw(wsi, (unsigned char *)eff_buf.token,
 564                                                              eff_buf.token_len))
 565                                 return -1;
 566                 } else
 567                         continue;
 568
 569                 /* no extension has more to spill */
 570
 571                 if (!ret)
 572                         continue;
 573
 574                 /*
 575                  * There's more to spill from an extension, but we just sent
 576                  * something... did that leave the pipe choked?
 577                  */
 578
 579                 if (!lws_send_pipe_choked(wsi))
 580                         /* no we could add more */
 581                         continue;
 582
 583                 fprintf(stderr, "choked in POLLOUT service\n");
 584
 585                 /*
 586                  * Yes, he's choked.  Leave the POLLOUT masked on so we will
 587                  * come back here when he is unchoked.  Don't call the user
 588                  * callback to enforce ordering of spilling, he'll get called
 589                  * when we come back here and there's nothing more to spill.
 590                  */
 591
 592                 return 0;
 593         }
 594
 595         wsi->extension_data_pending = 0;
 596
 597 user_service:
 598         /* one shot */
 599
 600         pollfd->events &= ~POLLOUT;
 601
 602         /* external POLL support via protocol 0 */
 603         context->protocols[0].callback(context, wsi,
 604                 LWS_CALLBACK_CLEAR_MODE_POLL_FD,
 605                 (void *)(long)wsi->sock, NULL, POLLOUT);
 606
 607         if (wsi->mode == LWS_CONNMODE_WS_CLIENT)
 608                 n = LWS_CALLBACK_CLIENT_WRITEABLE;
 609         else
 610                 n = LWS_CALLBACK_SERVER_WRITEABLE;
 611
 612         wsi->protocol->callback(context, wsi, n, wsi->user_space, NULL, 0);
 613
 614         return 0;
 615 }
 616
 617
 618
 619 /**
 620  * libwebsocket_service_fd() - Service polled socket with something waiting
 621  * @context:    Websocket context
 622  * @pollfd:     The pollfd entry describing the socket fd and which events
 623  *              happened.
 624  *
 625  *      This function closes any active connections and then frees the
 626  *      context.  After calling this, any further use of the context is
 627  *      undefined.
 628  */
 629
 630 int
 631 libwebsocket_service_fd(struct libwebsocket_context *context,
 632                                                           struct pollfd *pollfd)
 633 {
 634         unsigned char buf[LWS_SEND_BUFFER_PRE_PADDING + 1 + MAX_BROADCAST_PAYLOAD +
 635                                                   LWS_SEND_BUFFER_POST_PADDING];
 636         struct libwebsocket *wsi;
 637         struct libwebsocket *new_wsi;
 638         int n;
 639         int m;
 640         size_t len;
 641         int accept_fd;
 642         unsigned int clilen;
 643         struct sockaddr_in cli_addr;
 644         struct timeval tv;
 645         static const char magic_websocket_guid[] =
 646                                          "258EAFA5-E914-47DA-95CA-C5AB0DC85B11";
 647         static const char magic_websocket_04_masking_guid[] =
 648                                          "61AC5F19-FBBA-4540-B96F-6561F1AB40A8";
 649         char hash[20];
 650         char pkt[1024];
 651         char *p = &pkt[0];
 652         const char *pc;
 653         const char *c;
 654         int more = 1;
 655         int okay = 0;
 656         char ext_name[128];
 657         struct lws_tokens eff_buf;
 658         int ext_count = 0;
 659         struct libwebsocket_extension *ext;
 660         int opt = 1;
 661
 662 #ifdef LWS_OPENSSL_SUPPORT
 663         char ssl_err_buf[512];
 664 #endif
 665         /*
 666          * you can call us with pollfd = NULL to just allow the once-per-second
 667          * global timeout checks; if less than a second since the last check
 668          * it returns immediately then.
 669          */
 670
 671         gettimeofday(&tv, NULL);
 672
 673         if (context->last_timeout_check_s != tv.tv_sec) {
 674                 context->last_timeout_check_s = tv.tv_sec;
 675
 676                 /* global timeout check once per second */
 677
 678                 for (n = 0; n < context->fds_count; n++) {
 679                         wsi = wsi_from_fd(context, context->fds[n].fd);
 680                         if (!wsi->pending_timeout)
 681                                 continue;
 682
 683                         /*
 684                          * if we went beyond the allowed time, kill the
 685                          * connection
 686                          */
 687
 688                         if (tv.tv_sec > wsi->pending_timeout_limit) {
 689                                 fprintf(stderr, "TIMEDOUT WAITING\n");
 690                                 libwebsocket_close_and_free_session(context,
 691                                                 wsi, LWS_CLOSE_STATUS_NOSTATUS);
 692                         }
 693                 }
 694         }
 695
 696         /* just here for timeout management? */
 697
 698         if (pollfd == NULL)
 699                 return 0;
 700
 701         /* no, here to service a socket descriptor */
 702
 703         wsi = wsi_from_fd(context, pollfd->fd);
 704
 705         if (wsi == NULL)
 706                 return 1;
 707
 708         switch (wsi->mode) {
 709         case LWS_CONNMODE_SERVER_LISTENER:
 710
 711                 /* pollin means a client has connected to us then */
 712
 713                 if (!pollfd->revents & POLLIN)
 714                         break;
 715
 716                 /* listen socket got an unencrypted connection... */
 717
 718                 clilen = sizeof(cli_addr);
 719                 accept_fd  = accept(pollfd->fd, (struct sockaddr *)&cli_addr,
 720                                                                        &clilen);
 721                 if (accept_fd < 0) {
 722                         fprintf(stderr, "ERROR on accept");
 723                         break;
 724                 }
 725
 726                 /* Disable Nagle */
 727                 opt = 1;
 728                 setsockopt(accept_fd, SOL_TCP, TCP_NODELAY, &opt, sizeof(opt));
 729
 730                 if (context->fds_count >= MAX_CLIENTS) {
 731                         fprintf(stderr, "too busy to accept new client\n");
 732 #ifdef WIN32
 733                         closesocket(accept_fd);
 734 #else
 735                         close(accept_fd);
 736 #endif
 737                         break;
 738                 }
 739
 740                 /*
 741                  * look at who we connected to and give user code a chance
 742                  * to reject based on client IP.  There's no protocol selected
 743                  * yet so we issue this to protocols[0]
 744                  */
 745
 746                 if ((context->protocols[0].callback)(context, wsi,
 747                                 LWS_CALLBACK_FILTER_NETWORK_CONNECTION,
 748                                              (void*)(long)accept_fd, NULL, 0)) {
 749                         fprintf(stderr, "Callback denied network connection\n");
 750 #ifdef WIN32
 751                         closesocket(accept_fd);
 752 #else
 753                         close(accept_fd);
 754 #endif
 755                         break;
 756                 }
 757
 758                 /* accepting connection to main listener */
 759
 760                 new_wsi = malloc(sizeof(struct libwebsocket));
 761                 if (new_wsi == NULL) {
 762                         fprintf(stderr, "Out of memory for new connection\n");
 763                         break;
 764                 }
 765
 766                 memset(new_wsi, 0, sizeof (struct libwebsocket));
 767                 new_wsi->sock = accept_fd;
 768                 new_wsi->count_active_extensions = 0;
 769                 new_wsi->pending_timeout = NO_PENDING_TIMEOUT;
 770
 771 #ifdef LWS_OPENSSL_SUPPORT
 772                 new_wsi->ssl = NULL;
 773
 774                 if (context->use_ssl) {
 775
 776                         new_wsi->ssl = SSL_new(context->ssl_ctx);
 777                         if (new_wsi->ssl == NULL) {
 778                                 fprintf(stderr, "SSL_new failed: %s\n",
 779                                     ERR_error_string(SSL_get_error(
 780                                     new_wsi->ssl, 0), NULL));
 781                                     libwebsockets_decode_ssl_error();
 782                                 free(new_wsi);
 783                                 break;
 784                         }
 785
 786                         SSL_set_fd(new_wsi->ssl, accept_fd);
 787
 788                         n = SSL_accept(new_wsi->ssl);
 789                         if (n != 1) {
 790                                 /*
 791                                  * browsers seem to probe with various
 792                                  * ssl params which fail then retry
 793                                  * and succeed
 794                                  */
 795                                 debug("SSL_accept failed skt %u: %s\n",
 796                                       pollfd->fd,
 797                                       ERR_error_string(SSL_get_error(
 798                                       new_wsi->ssl, n), NULL));
 799                                 SSL_free(
 800                                        new_wsi->ssl);
 801                                 free(new_wsi);
 802                                 break;
 803                         }
 804
 805                         debug("accepted new SSL conn  "
 806                               "port %u on fd=%d SSL ver %s\n",
 807                                 ntohs(cli_addr.sin_port), accept_fd,
 808                                   SSL_get_version(new_wsi->ssl));
 809
 810                 } else
 811 #endif
 812                         debug("accepted new conn  port %u on fd=%d\n",
 813                                           ntohs(cli_addr.sin_port), accept_fd);
 814
 815                 /* intialize the instance struct */
 816
 817                 new_wsi->state = WSI_STATE_HTTP;
 818                 new_wsi->name_buffer_pos = 0;
 819                 new_wsi->mode = LWS_CONNMODE_WS_SERVING;
 820
 821                 for (n = 0; n < WSI_TOKEN_COUNT; n++) {
 822                         new_wsi->utf8_token[n].token = NULL;
 823                         new_wsi->utf8_token[n].token_len = 0;
 824                 }
 825
 826                 /*
 827                  * these can only be set once the protocol is known
 828                  * we set an unestablished connection's protocol pointer
 829                  * to the start of the supported list, so it can look
 830                  * for matching ones during the handshake
 831                  */
 832                 new_wsi->protocol = context->protocols;
 833                 new_wsi->user_space = NULL;
 834
 835                 /*
 836                  * Default protocol is 76 / 00
 837                  * After 76, there's a header specified to inform which
 838                  * draft the client wants, when that's seen we modify
 839                  * the individual connection's spec revision accordingly
 840                  */
 841                 new_wsi->ietf_spec_revision = 0;
 842
 843                 insert_wsi(context, new_wsi);
 844
 845                 /*
 846                  * make sure NO events are seen yet on this new socket
 847                  * (otherwise we inherit old fds[client].revents from
 848                  * previous socket there and die mysteriously! )
 849                  */
 850                 context->fds[context->fds_count].revents = 0;
 851
 852                 context->fds[context->fds_count].events = POLLIN;
 853                 context->fds[context->fds_count++].fd = accept_fd;
 854
 855                 /* external POLL support via protocol 0 */
 856                 context->protocols[0].callback(context, new_wsi,
 857                         LWS_CALLBACK_ADD_POLL_FD,
 858                         (void *)(long)accept_fd, NULL, POLLIN);
 859
 860                 break;
 861
 862         case LWS_CONNMODE_BROADCAST_PROXY_LISTENER:
 863
 864                 /* as we are listening, POLLIN means accept() is needed */
 865
 866                 if (!pollfd->revents & POLLIN)
 867                         break;
 868
 869                 /* listen socket got an unencrypted connection... */
 870
 871                 clilen = sizeof(cli_addr);
 872                 accept_fd  = accept(pollfd->fd, (struct sockaddr *)&cli_addr,
 873                                                                        &clilen);
 874                 if (accept_fd < 0) {
 875                         fprintf(stderr, "ERROR on accept");
 876                         break;
 877                 }
 878
 879                 if (context->fds_count >= MAX_CLIENTS) {
 880                         fprintf(stderr, "too busy to accept new broadcast "
 881                                                               "proxy client\n");
 882 #ifdef WIN32
 883                         closesocket(accept_fd);
 884 #else
 885                         close(accept_fd);
 886 #endif
 887                         break;
 888                 }
 889
 890                 /* create a dummy wsi for the connection and add it */
 891
 892                 new_wsi = malloc(sizeof(struct libwebsocket));
 893                 memset(new_wsi, 0, sizeof (struct libwebsocket));
 894                 new_wsi->sock = accept_fd;
 895                 new_wsi->mode = LWS_CONNMODE_BROADCAST_PROXY;
 896                 new_wsi->state = WSI_STATE_ESTABLISHED;
 897                 new_wsi->count_active_extensions = 0;
 898                 /* note which protocol we are proxying */
 899                 new_wsi->protocol_index_for_broadcast_proxy =
 900                                         wsi->protocol_index_for_broadcast_proxy;
 901                 insert_wsi(context, new_wsi);
 902
 903                 /* add connected socket to internal poll array */
 904
 905                 context->fds[context->fds_count].revents = 0;
 906                 context->fds[context->fds_count].events = POLLIN;
 907                 context->fds[context->fds_count++].fd = accept_fd;
 908
 909                 /* external POLL support via protocol 0 */
 910                 context->protocols[0].callback(context, new_wsi,
 911                         LWS_CALLBACK_ADD_POLL_FD,
 912                         (void *)(long)accept_fd, NULL, POLLIN);
 913
 914                 break;
 915
 916         case LWS_CONNMODE_BROADCAST_PROXY:
 917
 918                 /* handle session socket closed */
 919
 920                 if (pollfd->revents & (POLLERR | POLLHUP)) {
 921
 922                         debug("Session Socket %p (fd=%d) dead\n",
 923                                 (void *)wsi, pollfd->fd);
 924
 925                         libwebsocket_close_and_free_session(context, wsi,
 926                                                        LWS_CLOSE_STATUS_NORMAL);
 927                         return 1;
 928                 }
 929
 930                 /*
 931                  * either extension code with stuff to spill, or the user code,
 932                  * requested a callback when it was OK to write
 933                  */
 934
 935                 if (pollfd->revents & POLLOUT)
 936                         if (lws_handle_POLLOUT_event(context, wsi, pollfd) < 0) {
 937                                 libwebsocket_close_and_free_session(context, wsi,
 938                                                        LWS_CLOSE_STATUS_NORMAL);
 939                                 return 1;
 940                         }
 941
 942                 /* any incoming data ready? */
 943
 944                 if (!(pollfd->revents & POLLIN))
 945                         break;
 946
 947                 /* get the issued broadcast payload from the socket */
 948
 949                 len = read(pollfd->fd, buf + LWS_SEND_BUFFER_PRE_PADDING,
 950                                                          MAX_BROADCAST_PAYLOAD);
 951                 if (len < 0) {
 952                         fprintf(stderr, "Error reading broadcast payload\n");
 953                         break;
 954                 }
 955
 956                 /* broadcast it to all guys with this protocol index */
 957
 958                 for (n = 0; n < FD_HASHTABLE_MODULUS; n++) {
 959
 960                         for (m = 0; m < context->fd_hashtable[n].length; m++) {
 961
 962                                 new_wsi = context->fd_hashtable[n].wsi[m];
 963
 964                                 /* only to clients we are serving to */
 965
 966                                 if (new_wsi->mode != LWS_CONNMODE_WS_SERVING)
 967                                         continue;
 968
 969                                 /*
 970                                  * never broadcast to non-established
 971                                  * connection
 972                                  */
 973
 974                                 if (new_wsi->state != WSI_STATE_ESTABLISHED)
 975                                         continue;
 976
 977                                 /*
 978                                  * only broadcast to connections using
 979                                  * the requested protocol
 980                                  */
 981
 982                                 if (new_wsi->protocol->protocol_index !=
 983                                         wsi->protocol_index_for_broadcast_proxy)
 984                                         continue;
 985
 986                                 /* broadcast it to this connection */
 987
 988                                 new_wsi->protocol->callback(context, new_wsi,
 989                                         LWS_CALLBACK_BROADCAST,
 990                                         new_wsi->user_space,
 991                                         buf + LWS_SEND_BUFFER_PRE_PADDING, len);
 992                         }
 993                 }
 994                 break;
 995
 996         case LWS_CONNMODE_WS_CLIENT_WAITING_PROXY_REPLY:
 997
 998                 /* handle proxy hung up on us */
 999
1000                 if (pollfd->revents & (POLLERR | POLLHUP)) {
1001
1002                         fprintf(stderr, "Proxy connection %p (fd=%d) dead\n",
1003                                 (void *)wsi, pollfd->fd);
1004
1005                         libwebsocket_close_and_free_session(context, wsi,
1006                                                      LWS_CLOSE_STATUS_NOSTATUS);
1007                         return 1;
1008                 }
1009
1010                 n = recv(wsi->sock, pkt, sizeof pkt, 0);
1011                 if (n < 0) {
1012                         libwebsocket_close_and_free_session(context, wsi,
1013                                                      LWS_CLOSE_STATUS_NOSTATUS);
1014                         fprintf(stderr, "ERROR reading from proxy socket\n");
1015                         return 1;
1016                 }
1017
1018                 pkt[13] = '\0';
1019                 if (strcmp(pkt, "HTTP/1.0 200 ") != 0) {
1020                         libwebsocket_close_and_free_session(context, wsi,
1021                                                      LWS_CLOSE_STATUS_NOSTATUS);
1022                         fprintf(stderr, "ERROR from proxy: %s\n", pkt);
1023                         return 1;
1024                 }
1025
1026                 /* clear his proxy connection timeout */
1027
1028                 libwebsocket_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
1029
1030                 /* fallthru */
1031
1032         case LWS_CONNMODE_WS_CLIENT_ISSUE_HANDSHAKE:
1033
1034         #ifdef LWS_OPENSSL_SUPPORT
1035                 if (wsi->use_ssl) {
1036
1037                         wsi->ssl = SSL_new(context->ssl_client_ctx);
1038                         wsi->client_bio = BIO_new_socket(wsi->sock,
1039                                                                    BIO_NOCLOSE);
1040                         SSL_set_bio(wsi->ssl, wsi->client_bio, wsi->client_bio);
1041
1042                         SSL_set_ex_data(wsi->ssl,
1043                                         openssl_websocket_private_data_index,
1044                                                                        context);
1045
1046                         if (SSL_connect(wsi->ssl) <= 0) {
1047                                 fprintf(stderr, "SSL connect error %s\n",
1048                                         ERR_error_string(ERR_get_error(),
1049                                                                   ssl_err_buf));
1050                                 libwebsocket_close_and_free_session(context, wsi,
1051                                                      LWS_CLOSE_STATUS_NOSTATUS);
1052                                 return 1;
1053                         }
1054
1055                         n = SSL_get_verify_result(wsi->ssl);
1056                         if ((n != X509_V_OK) && (
1057                                 n != X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT ||
1058                                                            wsi->use_ssl != 2)) {
1059
1060                                 fprintf(stderr, "server's cert didn't "
1061                                                            "look good %d\n", n);
1062                                 libwebsocket_close_and_free_session(context,
1063                                                 wsi, LWS_CLOSE_STATUS_NOSTATUS);
1064                                 return 1;
1065                         }
1066                 } else {
1067                         wsi->ssl = NULL;
1068         #endif
1069
1070
1071         #ifdef LWS_OPENSSL_SUPPORT
1072                 }
1073         #endif
1074
1075                 /*
1076                  * create the random key
1077                  */
1078
1079                 n = libwebsockets_get_random(context, hash, 16);
1080                 if (n != 16) {
1081                         fprintf(stderr, "Unable to read from random dev %s\n",
1082                                                         SYSTEM_RANDOM_FILEPATH);
1083                         free(wsi->c_path);
1084                         free(wsi->c_host);
1085                         if (wsi->c_origin)
1086                                 free(wsi->c_origin);
1087                         if (wsi->c_protocol)
1088                                 free(wsi->c_protocol);
1089                         libwebsocket_close_and_free_session(context, wsi,
1090                                                      LWS_CLOSE_STATUS_NOSTATUS);
1091                         return 1;
1092                 }
1093
1094                 lws_b64_encode_string(hash, 16, wsi->key_b64,
1095                                                            sizeof wsi->key_b64);
1096
1097                 /*
1098                  * 00 example client handshake
1099                  *
1100                  * GET /socket.io/websocket HTTP/1.1
1101                  * Upgrade: WebSocket
1102                  * Connection: Upgrade
1103                  * Host: 127.0.0.1:9999
1104                  * Origin: http://127.0.0.1
1105                  * Sec-WebSocket-Key1: 1 0 2#0W 9 89 7  92 ^
1106                  * Sec-WebSocket-Key2: 7 7Y 4328 B2v[8(z1
1107                  * Cookie: socketio=websocket
1108                  *
1109                  * (Á®Ä0¶†≥
1110                  *
1111                  * 04 example client handshake
1112                  *
1113                  * GET /chat HTTP/1.1
1114                  * Host: server.example.com
1115                  * Upgrade: websocket
1116                  * Connection: Upgrade
1117                  * Sec-WebSocket-Key: dGhlIHNhbXBsZSBub25jZQ==
1118                  * Sec-WebSocket-Origin: http://example.com
1119                  * Sec-WebSocket-Protocol: chat, superchat
1120                  * Sec-WebSocket-Version: 4
1121                  */
1122
1123                 p += sprintf(p, "GET %s HTTP/1.1\x0d\x0a", wsi->c_path);
1124
1125                 if (wsi->ietf_spec_revision == 0) {
1126                         unsigned char spaces_1, spaces_2;
1127                         unsigned int max_1, max_2;
1128                         unsigned int num_1, num_2;
1129                         unsigned long product_1, product_2;
1130                         char key_1[40];
1131                         char key_2[40];
1132                         unsigned int seed;
1133                         unsigned int count;
1134                         char challenge[16];
1135
1136                         libwebsockets_get_random(context, &spaces_1,
1137                                                                   sizeof(char));
1138                         libwebsockets_get_random(context, &spaces_2,
1139                                                                   sizeof(char));
1140
1141                         spaces_1 = (spaces_1 % 12) + 1;
1142                         spaces_2 = (spaces_2 % 12) + 1;
1143
1144                         max_1 = 4294967295 / spaces_1;
1145                         max_2 = 4294967295 / spaces_2;
1146
1147                         libwebsockets_get_random(context, &num_1, sizeof(int));
1148                         libwebsockets_get_random(context, &num_2, sizeof(int));
1149
1150                         num_1 = (num_1 % max_1);
1151                         num_2 = (num_2 % max_2);
1152
1153                         challenge[0] = num_1 >> 24;
1154                         challenge[1] = num_1 >> 16;
1155                         challenge[2] = num_1 >> 8;
1156                         challenge[3] = num_1;
1157                         challenge[4] = num_2 >> 24;
1158                         challenge[5] = num_2 >> 16;
1159                         challenge[6] = num_2 >> 8;
1160                         challenge[7] = num_2;
1161
1162                         product_1 = num_1 * spaces_1;
1163                         product_2 = num_2 * spaces_2;
1164
1165                         sprintf(key_1, "%lu", product_1);
1166                         sprintf(key_2, "%lu", product_2);
1167
1168                         libwebsockets_get_random(context, &seed, sizeof(int));
1169                         libwebsockets_get_random(context, &count, sizeof(int));
1170
1171                         libwebsockets_00_spam(key_1, (count % 12) + 1, seed);
1172
1173                         libwebsockets_get_random(context, &seed, sizeof(int));
1174                         libwebsockets_get_random(context, &count, sizeof(int));
1175
1176                         libwebsockets_00_spam(key_2, (count % 12) + 1, seed);
1177
1178                         libwebsockets_get_random(context, &seed, sizeof(int));
1179
1180                         libwebsockets_00_spaceout(key_1, spaces_1, seed);
1181                         libwebsockets_00_spaceout(key_2, spaces_2, seed >> 16);
1182
1183                         p += sprintf(p, "Upgrade: websocket\x0d\x0a"
1184                                 "Connection: Upgrade\x0d\x0aHost: %s\x0d\x0a",
1185                                 wsi->c_host);
1186                         if (wsi->c_origin)
1187                                 p += sprintf(p, "Origin: %s\x0d\x0a",
1188                                 wsi->c_origin);
1189
1190                         if (wsi->c_protocol)
1191                                 p += sprintf(p, "Sec-WebSocket-Protocol: %s"
1192                                                  "\x0d\x0a", wsi->c_protocol);
1193
1194                         p += sprintf(p, "Sec-WebSocket-Key1: %s\x0d\x0a",
1195                                 key_1);
1196                         p += sprintf(p, "Sec-WebSocket-Key2: %s\x0d\x0a",
1197                                 key_2);
1198
1199                         /* give userland a chance to append, eg, cookies */
1200
1201                         context->protocols[0].callback(context, wsi,
1202                                 LWS_CALLBACK_CLIENT_APPEND_HANDSHAKE_HEADER,
1203                                         NULL, &p, (pkt + sizeof(pkt)) - p - 12);
1204
1205                         p += sprintf(p, "\x0d\x0a");
1206
1207                         if (libwebsockets_get_random(context, p, 8) != 8)
1208                                 return -1;
1209                         memcpy(&challenge[8], p, 8);
1210                         p += 8;
1211
1212                         /* precompute what we want to see from the server */
1213
1214                         MD5((unsigned char *)challenge, 16,
1215                            (unsigned char *)wsi->initial_handshake_hash_base64);
1216
1217                         goto issue_hdr;
1218                 }
1219
1220                 p += sprintf(p, "Host: %s\x0d\x0a", wsi->c_host);
1221                 p += sprintf(p, "Upgrade: websocket\x0d\x0a");
1222                 p += sprintf(p, "Connection: Upgrade\x0d\x0a"
1223                                         "Sec-WebSocket-Key: ");
1224                 strcpy(p, wsi->key_b64);
1225                 p += strlen(wsi->key_b64);
1226                 p += sprintf(p, "\x0d\x0a");
1227                 if (wsi->c_origin)
1228                         p += sprintf(p, "Sec-WebSocket-Origin: %s\x0d\x0a",
1229                                                                  wsi->c_origin);
1230                 if (wsi->c_protocol)
1231                         p += sprintf(p, "Sec-WebSocket-Protocol: %s\x0d\x0a",
1232                                                                wsi->c_protocol);
1233
1234                 /* tell the server what extensions we could support */
1235
1236                 p += sprintf(p, "Sec-WebSocket-Extensions: ");
1237
1238                 ext =context->extensions;
1239                 while (ext && ext->callback) {
1240
1241                         n = 0;
1242                         n = context->protocols[0].callback(context, wsi,
1243                                 LWS_CALLBACK_CLIENT_CONFIRM_EXTENSION_SUPPORTED,
1244                                         wsi->user_space, (char *)ext->name, 0);
1245
1246                         /*
1247                          * zero return from callback means
1248                          * go ahead and allow the extension,
1249                          * it's what we get if the callback is
1250                          * unhandled
1251                          */
1252
1253                         if (n) {
1254                                 ext++;
1255                                 continue;
1256                         }
1257
1258                         /* apply it */
1259
1260                         if (ext_count)
1261                                 *p++ = ',';
1262                         p += sprintf(p, "%s", ext->name);
1263                         ext_count++;
1264
1265                         ext++;
1266                 }
1267
1268                 p += sprintf(p, "\x0d\x0a");
1269
1270                 if (wsi->ietf_spec_revision)
1271                         p += sprintf(p, "Sec-WebSocket-Version: %d\x0d\x0a",
1272                                                        wsi->ietf_spec_revision);
1273
1274                 /* give userland a chance to append, eg, cookies */
1275
1276                 context->protocols[0].callback(context, wsi,
1277                         LWS_CALLBACK_CLIENT_APPEND_HANDSHAKE_HEADER,
1278                         NULL, &p, (pkt + sizeof(pkt)) - p - 12);
1279
1280                 p += sprintf(p, "\x0d\x0a");
1281
1282                 /* prepare the expected server accept response */
1283
1284                 strcpy((char *)buf, wsi->key_b64);
1285                 strcpy((char *)&buf[strlen((char *)buf)], magic_websocket_guid);
1286
1287                 SHA1(buf, strlen((char *)buf), (unsigned char *)hash);
1288
1289                 lws_b64_encode_string(hash, 20,
1290                                 wsi->initial_handshake_hash_base64,
1291                                      sizeof wsi->initial_handshake_hash_base64);
1292
1293 issue_hdr:
1294
1295                 /* done with these now */
1296
1297                 free(wsi->c_path);
1298                 free(wsi->c_host);
1299                 if (wsi->c_origin)
1300                         free(wsi->c_origin);
1301
1302                 /* send our request to the server */
1303
1304         #ifdef LWS_OPENSSL_SUPPORT
1305                 if (wsi->use_ssl)
1306                         n = SSL_write(wsi->ssl, pkt, p - pkt);
1307                 else
1308         #endif
1309                         n = send(wsi->sock, pkt, p - pkt, 0);
1310
1311                 if (n < 0) {
1312                         fprintf(stderr, "ERROR writing to client socket\n");
1313                         libwebsocket_close_and_free_session(context, wsi,
1314                                                      LWS_CLOSE_STATUS_NOSTATUS);
1315                         return 1;
1316                 }
1317
1318                 wsi->parser_state = WSI_TOKEN_NAME_PART;
1319                 wsi->mode = LWS_CONNMODE_WS_CLIENT_WAITING_SERVER_REPLY;
1320                 libwebsocket_set_timeout(wsi,
1321                                 PENDING_TIMEOUT_AWAITING_SERVER_RESPONSE, 5);
1322
1323                 break;
1324
1325         case LWS_CONNMODE_WS_CLIENT_WAITING_SERVER_REPLY:
1326
1327                 /* handle server hung up on us */
1328
1329                 if (pollfd->revents & (POLLERR | POLLHUP)) {
1330
1331                         fprintf(stderr, "Server connection %p (fd=%d) dead\n",
1332                                 (void *)wsi, pollfd->fd);
1333
1334                         goto bail3;
1335                 }
1336
1337
1338                 /* interpret the server response */
1339
1340                 /*
1341                  *  HTTP/1.1 101 Switching Protocols
1342                  *  Upgrade: websocket
1343                  *  Connection: Upgrade
1344                  *  Sec-WebSocket-Accept: me89jWimTRKTWwrS3aRrL53YZSo=
1345                  *  Sec-WebSocket-Nonce: AQIDBAUGBwgJCgsMDQ4PEC==
1346                  *  Sec-WebSocket-Protocol: chat
1347                  */
1348
1349         #ifdef LWS_OPENSSL_SUPPORT
1350                 if (wsi->use_ssl)
1351                         len = SSL_read(wsi->ssl, pkt, sizeof pkt);
1352                 else
1353         #endif
1354                         len = recv(wsi->sock, pkt, sizeof pkt, 0);
1355
1356                 if (len < 0) {
1357                         fprintf(stderr,
1358                                   "libwebsocket_client_handshake read error\n");
1359                         goto bail3;
1360                 }
1361
1362                 p = pkt;
1363                 for (n = 0; n < len; n++)
1364                         libwebsocket_parse(wsi, *p++);
1365
1366                 if (wsi->parser_state != WSI_PARSING_COMPLETE) {
1367                         fprintf(stderr, "libwebsocket_client_handshake "
1368                                         "server response failed parsing\n");
1369                         goto bail3;
1370                 }
1371
1372                 /*
1373                  * 00 / 76 -->
1374                  *
1375                  * HTTP/1.1 101 WebSocket Protocol Handshake
1376                  * Upgrade: WebSocket
1377                  * Connection: Upgrade
1378                  * Sec-WebSocket-Origin: http://127.0.0.1
1379                  * Sec-WebSocket-Location: ws://127.0.0.1:9999/socket.io/websocket
1380                  *
1381                  * xxxxxxxxxxxxxxxx
1382                  */
1383
1384                 if (wsi->ietf_spec_revision == 0) {
1385                         if (!wsi->utf8_token[WSI_TOKEN_HTTP].token_len ||
1386                             !wsi->utf8_token[WSI_TOKEN_UPGRADE].token_len ||
1387                             !wsi->utf8_token[WSI_TOKEN_CHALLENGE].token_len ||
1388                             !wsi->utf8_token[WSI_TOKEN_CONNECTION].token_len ||
1389                             (!wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len &&
1390                             wsi->c_protocol != NULL)) {
1391                                 fprintf(stderr, "libwebsocket_client_handshake "
1392                                                 "missing required header(s)\n");
1393                                 pkt[len] = '\0';
1394                                 fprintf(stderr, "%s", pkt);
1395                                 goto bail3;
1396                         }
1397
1398                         strtolower(wsi->utf8_token[WSI_TOKEN_HTTP].token);
1399                         if (strcmp(wsi->utf8_token[WSI_TOKEN_HTTP].token,
1400                                 "101 websocket protocol handshake")) {
1401                                 fprintf(stderr, "libwebsocket_client_handshake "
1402                                         "server sent bad HTTP response '%s'\n",
1403                                         wsi->utf8_token[WSI_TOKEN_HTTP].token);
1404                                 goto bail3;
1405                         }
1406
1407                         if (wsi->utf8_token[WSI_TOKEN_CHALLENGE].token_len <
1408                                                                            16) {
1409                                 fprintf(stderr, "libwebsocket_client_handshake "
1410                                         "challenge reply too short %d\n",
1411                                         wsi->utf8_token[
1412                                                 WSI_TOKEN_CHALLENGE].token_len);
1413                                 pkt[len] = '\0';
1414                                 fprintf(stderr, "%s", pkt);
1415                                 goto bail3;
1416
1417                         }
1418
1419                         goto select_protocol;
1420                 }
1421
1422                 /*
1423                  * well, what the server sent looked reasonable for syntax.
1424                  * Now let's confirm it sent all the necessary headers
1425                  */
1426
1427                  if (!wsi->utf8_token[WSI_TOKEN_HTTP].token_len ||
1428                         !wsi->utf8_token[WSI_TOKEN_UPGRADE].token_len ||
1429                         !wsi->utf8_token[WSI_TOKEN_CONNECTION].token_len ||
1430                         !wsi->utf8_token[WSI_TOKEN_ACCEPT].token_len ||
1431                         (!wsi->utf8_token[WSI_TOKEN_NONCE].token_len &&
1432                                            wsi->ietf_spec_revision == 4) ||
1433                         (!wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len &&
1434                                                      wsi->c_protocol != NULL)) {
1435                         fprintf(stderr, "libwebsocket_client_handshake "
1436                                                 "missing required header(s)\n");
1437                         pkt[len] = '\0';
1438                         fprintf(stderr, "%s", pkt);
1439                         goto bail3;
1440                 }
1441
1442                 /*
1443                  * Everything seems to be there, now take a closer look at what
1444                  * is in each header
1445                  */
1446
1447                 strtolower(wsi->utf8_token[WSI_TOKEN_HTTP].token);
1448                 if (strcmp(wsi->utf8_token[WSI_TOKEN_HTTP].token,
1449                                                    "101 switching protocols")) {
1450                         fprintf(stderr, "libwebsocket_client_handshake "
1451                                         "server sent bad HTTP response '%s'\n",
1452                                          wsi->utf8_token[WSI_TOKEN_HTTP].token);
1453                         goto bail3;
1454                 }
1455
1456                 strtolower(wsi->utf8_token[WSI_TOKEN_UPGRADE].token);
1457                 if (strcmp(wsi->utf8_token[WSI_TOKEN_UPGRADE].token,
1458                                                                  "websocket")) {
1459                         fprintf(stderr, "libwebsocket_client_handshake server "
1460                                         "sent bad Upgrade header '%s'\n",
1461                                       wsi->utf8_token[WSI_TOKEN_UPGRADE].token);
1462                         goto bail3;
1463                 }
1464
1465                 strtolower(wsi->utf8_token[WSI_TOKEN_CONNECTION].token);
1466                 if (strcmp(wsi->utf8_token[WSI_TOKEN_CONNECTION].token,
1467                                                                    "upgrade")) {
1468                         fprintf(stderr, "libwebsocket_client_handshake server "
1469                                         "sent bad Connection hdr '%s'\n",
1470                                    wsi->utf8_token[WSI_TOKEN_CONNECTION].token);
1471                         goto bail3;
1472                 }
1473
1474 select_protocol:
1475                 pc = wsi->c_protocol;
1476
1477                 /*
1478                  * confirm the protocol the server wants to talk was in the list
1479                  * of protocols we offered
1480                  */
1481
1482                 if (!wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len) {
1483
1484                         /*
1485                          * no protocol name to work from,
1486                          * default to first protocol
1487                          */
1488                         wsi->protocol = &context->protocols[0];
1489
1490                         free(wsi->c_protocol);
1491
1492                         goto check_accept;
1493                 }
1494
1495                 while (*pc && !okay) {
1496                         if ((!strncmp(pc,
1497                                 wsi->utf8_token[WSI_TOKEN_PROTOCOL].token,
1498                            wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len)) &&
1499                  (pc[wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len] == ',' ||
1500                    pc[wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len] == '\0')) {
1501                                 okay = 1;
1502                                 continue;
1503                         }
1504                         while (*pc && *pc != ',')
1505                                 pc++;
1506                         while (*pc && *pc != ' ')
1507                                 pc++;
1508                 }
1509
1510                 /* done with him now */
1511
1512                 if (wsi->c_protocol)
1513                         free(wsi->c_protocol);
1514
1515
1516                 if (!okay) {
1517                         fprintf(stderr, "libwebsocket_client_handshake server "
1518                                                 "sent bad protocol '%s'\n",
1519                                      wsi->utf8_token[WSI_TOKEN_PROTOCOL].token);
1520                         goto bail2;
1521                 }
1522
1523                 /*
1524                  * identify the selected protocol struct and set it
1525                  */
1526                 n = 0;
1527                 wsi->protocol = NULL;
1528                 while (context->protocols[n].callback) {
1529                         if (strcmp(wsi->utf8_token[WSI_TOKEN_PROTOCOL].token,
1530                                                context->protocols[n].name) == 0)
1531                                 wsi->protocol = &context->protocols[n];
1532                         n++;
1533                 }
1534
1535                 if (wsi->protocol == NULL) {
1536                         fprintf(stderr, "libwebsocket_client_handshake server "
1537                                         "requested protocol '%s', which we "
1538                                         "said we supported but we don't!\n",
1539                                      wsi->utf8_token[WSI_TOKEN_PROTOCOL].token);
1540                         goto bail2;
1541                 }
1542
1543
1544                 /* instantiate the accepted extensions */
1545
1546                 if (!wsi->utf8_token[WSI_TOKEN_EXTENSIONS].token_len)
1547                         goto check_accept;
1548
1549                 /*
1550                  * break down the list of server accepted extensions
1551                  * and go through matching them or identifying bogons
1552                  */
1553
1554                 c = wsi->utf8_token[WSI_TOKEN_EXTENSIONS].token;
1555                 n = 0;
1556                 while (more) {
1557
1558                         if (*c && *c != ',') {
1559                                 ext_name[n] = *c++;
1560                                 if (n < sizeof(ext_name) - 1)
1561                                         n++;
1562                                 continue;
1563                         }
1564                         ext_name[n] = '\0';
1565                         if (!*c)
1566                                 more = 0;
1567
1568                         /* check we actually support it */
1569
1570                         n = 0;
1571                         ext = wsi->protocol->owning_server->extensions;
1572                         while (ext && ext->callback) {
1573
1574                                 if (strcmp(ext_name, ext->name)) {
1575                                         ext++;
1576                                         continue;
1577                                 }
1578
1579                                 n = 1;
1580
1581                                 /* instantiate the extension on this conn */
1582
1583                                 wsi->active_extensions_user[
1584                                         wsi->count_active_extensions] =
1585                                              malloc(ext->per_session_data_size);
1586                                 wsi->active_extensions[
1587                                           wsi->count_active_extensions] = ext;
1588
1589                                 /* allow him to construct his context */
1590
1591                                 ext->callback(wsi->protocol->owning_server,
1592                                         ext, wsi,
1593                                            LWS_EXT_CALLBACK_CLIENT_CONSTRUCT,
1594                                                 wsi->active_extensions_user[
1595                                                  wsi->count_active_extensions],
1596                                                                        NULL, 0);
1597
1598                                 wsi->count_active_extensions++;
1599
1600                                 ext++;
1601                         }
1602
1603                         if (n == 0) {
1604                                 fprintf(stderr, "Server said we should use"
1605                                       "an unknown extension '%s'!\n", ext_name);
1606                                 goto bail2;
1607                         }
1608
1609                         n = 0;
1610                 }
1611
1612
1613         check_accept:
1614
1615                 if (wsi->ietf_spec_revision == 0) {
1616
1617                         if (memcmp(wsi->initial_handshake_hash_base64,
1618                               wsi->utf8_token[WSI_TOKEN_CHALLENGE].token, 16)) {
1619                                 fprintf(stderr, "libwebsocket_client_handshake "
1620                                                "failed 00 challenge compare\n");
1621                                         pkt[len] = '\0';
1622                                         fprintf(stderr, "%s", pkt);
1623                                         goto bail2;
1624                         }
1625
1626                         goto accept_ok;
1627                 }
1628
1629                 /*
1630                  * Confirm his accept token is the one we precomputed
1631                  */
1632
1633                 if (strcmp(wsi->utf8_token[WSI_TOKEN_ACCEPT].token,
1634                                           wsi->initial_handshake_hash_base64)) {
1635                         fprintf(stderr, "libwebsocket_client_handshake server "
1636                                 "sent bad ACCEPT '%s' vs computed '%s'\n",
1637                                 wsi->utf8_token[WSI_TOKEN_ACCEPT].token,
1638                                             wsi->initial_handshake_hash_base64);
1639                         goto bail2;
1640                 }
1641
1642                 if (wsi->ietf_spec_revision == 4) {
1643                         /*
1644                          * Calculate the 04 masking key to use when
1645                          * sending data to server
1646                          */
1647
1648                         strcpy((char *)buf, wsi->key_b64);
1649                         p = (char *)buf + strlen(wsi->key_b64);
1650                         strcpy(p, wsi->utf8_token[WSI_TOKEN_NONCE].token);
1651                         p += wsi->utf8_token[WSI_TOKEN_NONCE].token_len;
1652                         strcpy(p, magic_websocket_04_masking_guid);
1653                         SHA1(buf, strlen((char *)buf), wsi->masking_key_04);
1654                 }
1655 accept_ok:
1656
1657                 /* allocate the per-connection user memory (if any) */
1658
1659                 if (wsi->protocol->per_session_data_size) {
1660                         wsi->user_space = malloc(
1661                                           wsi->protocol->per_session_data_size);
1662                         if (wsi->user_space  == NULL) {
1663                                 fprintf(stderr, "Out of memory for "
1664                                                            "conn user space\n");
1665                                 goto bail2;
1666                         }
1667                 } else
1668                         wsi->user_space = NULL;
1669
1670                 /* clear his proxy connection timeout */
1671
1672                 libwebsocket_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
1673
1674                 /* mark him as being alive */
1675
1676                 wsi->state = WSI_STATE_ESTABLISHED;
1677                 wsi->mode = LWS_CONNMODE_WS_CLIENT;
1678
1679                 fprintf(stderr, "handshake OK for protocol %s\n",
1680                                                            wsi->protocol->name);
1681
1682                 /* call him back to inform him he is up */
1683
1684                 wsi->protocol->callback(context, wsi,
1685                                  LWS_CALLBACK_CLIENT_ESTABLISHED,
1686                                  wsi->user_space,
1687                                  NULL, 0);
1688
1689                 break;
1690
1691 bail3:
1692                 if (wsi->c_protocol)
1693                         free(wsi->c_protocol);
1694
1695 bail2:
1696                 libwebsocket_close_and_free_session(context, wsi,
1697                                                      LWS_CLOSE_STATUS_NOSTATUS);
1698                 return 1;
1699
1700
1701         case LWS_CONNMODE_WS_SERVING:
1702         case LWS_CONNMODE_WS_CLIENT:
1703
1704                 /* handle session socket closed */
1705
1706                 if (pollfd->revents & (POLLERR | POLLHUP)) {
1707
1708                         fprintf(stderr, "Session Socket %p (fd=%d) dead\n",
1709                                 (void *)wsi, pollfd->fd);
1710
1711                         libwebsocket_close_and_free_session(context, wsi,
1712                                                      LWS_CLOSE_STATUS_NOSTATUS);
1713                         return 1;
1714                 }
1715
1716                 /* the guy requested a callback when it was OK to write */
1717
1718                 if ((pollfd->revents & POLLOUT) &&
1719                                             wsi->state == WSI_STATE_ESTABLISHED)
1720                         if (lws_handle_POLLOUT_event(context, wsi,
1721                                                                   pollfd) < 0) {
1722                                 libwebsocket_close_and_free_session(
1723                                          context, wsi, LWS_CLOSE_STATUS_NORMAL);
1724                                 return 1;
1725                         }
1726
1727
1728                 /* any incoming data ready? */
1729
1730                 if (!(pollfd->revents & POLLIN))
1731                         break;
1732
1733 #ifdef LWS_OPENSSL_SUPPORT
1734                 if (wsi->ssl)
1735                         eff_buf.token_len = SSL_read(wsi->ssl, buf, sizeof buf);
1736                 else
1737 #endif
1738                         eff_buf.token_len =
1739                                            recv(pollfd->fd, buf, sizeof buf, 0);
1740
1741                 if (eff_buf.token_len < 0) {
1742                         fprintf(stderr, "Socket read returned %d\n",
1743                                                             eff_buf.token_len);
1744                         break;
1745                 }
1746                 if (!eff_buf.token_len) {
1747                         libwebsocket_close_and_free_session(context, wsi,
1748                                                      LWS_CLOSE_STATUS_NOSTATUS);
1749                         return 1;
1750                 }
1751
1752                 /*
1753                  * give any active extensions a chance to munge the buffer
1754                  * before parse.  We pass in a pointer to an lws_tokens struct
1755                  * prepared with the default buffer and content length that's in
1756                  * there.  Rather than rewrite the default buffer, extensions
1757                  * that expect to grow the buffer can adapt .token to
1758                  * point to their own per-connection buffer in the extension
1759                  * user allocation.  By default with no extensions or no
1760                  * extension callback handling, just the normal input buffer is
1761                  * used then so it is efficient.
1762                  */
1763
1764                 eff_buf.token = (char *)buf;
1765
1766                 more = 1;
1767                 while (more) {
1768
1769                         more = 0;
1770
1771                         for (n = 0; n < wsi->count_active_extensions; n++) {
1772                                 m = wsi->active_extensions[n]->callback(context,
1773                                         wsi->active_extensions[n], wsi,
1774                                         LWS_EXT_CALLBACK_PACKET_RX_PREPARSE,
1775                                         wsi->active_extensions_user[n],
1776                                                                    &eff_buf, 0);
1777                                 if (m < 0) {
1778                                         fprintf(stderr, "Extension reports fatal error\n");
1779                                         libwebsocket_close_and_free_session(context, wsi,
1780                                                              LWS_CLOSE_STATUS_NOSTATUS);
1781                                         return 1;
1782                                 }
1783                                 if (m)
1784                                         more = 1;
1785                         }
1786
1787                         /* service incoming data */
1788
1789                         if (eff_buf.token_len) {
1790                                 n = libwebsocket_read(context, wsi,
1791                                      (unsigned char *)eff_buf.token, eff_buf.token_len);
1792                                 if (n < 0)
1793                                         /* we closed wsi */
1794                                         return 1;
1795                         }
1796
1797                         eff_buf.token = NULL;
1798                         eff_buf.token_len = 0;
1799                 }
1800                 break;
1801         }
1802
1803         return 0;
1804 }
1805
1806
1807 /**
1808  * libwebsocket_context_destroy() - Destroy the websocket context
1809  * @context:    Websocket context
1810  *
1811  *      This function closes any active connections and then frees the
1812  *      context.  After calling this, any further use of the context is
1813  *      undefined.
1814  */
1815 void
1816 libwebsocket_context_destroy(struct libwebsocket_context *context)
1817 {
1818         int n;
1819         int m;
1820         struct libwebsocket *wsi;
1821
1822         for (n = 0; n < FD_HASHTABLE_MODULUS; n++)
1823                 for (m = 0; m < context->fd_hashtable[n].length; m++) {
1824                         wsi = context->fd_hashtable[n].wsi[m];
1825                         libwebsocket_close_and_free_session(context, wsi,
1826                                                     LWS_CLOSE_STATUS_GOINGAWAY);
1827                 }
1828
1829 #ifdef WIN32
1830 #else
1831         close(context->fd_random);
1832 #endif
1833
1834 #ifdef LWS_OPENSSL_SUPPORT
1835         if (context->ssl_ctx)
1836                 SSL_CTX_free(context->ssl_ctx);
1837         if (context->ssl_client_ctx)
1838                 SSL_CTX_free(context->ssl_client_ctx);
1839 #endif
1840
1841         free(context);
1842
1843 #ifdef WIN32
1844         WSACleanup();
1845 #endif
1846 }
1847
1848 /**
1849  * libwebsocket_service() - Service any pending websocket activity
1850  * @context:    Websocket context
1851  * @timeout_ms: Timeout for poll; 0 means return immediately if nothing needed
1852  *              service otherwise block and service immediately, returning
1853  *              after the timeout if nothing needed service.
1854  *
1855  *      This function deals with any pending websocket traffic, for three
1856  *      kinds of event.  It handles these events on both server and client
1857  *      types of connection the same.
1858  *
1859  *      1) Accept new connections to our context's server
1860  *
1861  *      2) Perform pending broadcast writes initiated from other forked
1862  *         processes (effectively serializing asynchronous broadcasts)
1863  *
1864  *      3) Call the receive callback for incoming frame data received by
1865  *          server or client connections.
1866  *
1867  *      You need to call this service function periodically to all the above
1868  *      functions to happen; if your application is single-threaded you can
1869  *      just call it in your main event loop.
1870  *
1871  *      Alternatively you can fork a new process that asynchronously handles
1872  *      calling this service in a loop.  In that case you are happy if this
1873  *      call blocks your thread until it needs to take care of something and
1874  *      would call it with a large nonzero timeout.  Your loop then takes no
1875  *      CPU while there is nothing happening.
1876  *
1877  *      If you are calling it in a single-threaded app, you don't want it to
1878  *      wait around blocking other things in your loop from happening, so you
1879  *      would call it with a timeout_ms of 0, so it returns immediately if
1880  *      nothing is pending, or as soon as it services whatever was pending.
1881  */
1882
1883
1884 int
1885 libwebsocket_service(struct libwebsocket_context *context, int timeout_ms)
1886 {
1887         int n;
1888
1889         /* stay dead once we are dead */
1890
1891         if (context == NULL)
1892                 return 1;
1893
1894         /* wait for something to need service */
1895
1896         n = poll(context->fds, context->fds_count, timeout_ms);
1897         if (n == 0) /* poll timeout */
1898                 return 0;
1899
1900         if (n < 0) {
1901                 /*
1902                 fprintf(stderr, "Listen Socket dead\n");
1903                 */
1904                 return 1;
1905         }
1906
1907         /* handle accept on listening socket? */
1908
1909         for (n = 0; n < context->fds_count; n++)
1910                 if (context->fds[n].revents)
1911                         libwebsocket_service_fd(context, &context->fds[n]);
1912
1913         return 0;
1914 }
1915
1916 /**
1917  * libwebsocket_callback_on_writable() - Request a callback when this socket
1918  *                                       becomes able to be written to without
1919  *                                       blocking
1920  *
1921  * @context:    libwebsockets context
1922  * @wsi:        Websocket connection instance to get callback for
1923  */
1924
1925 int
1926 libwebsocket_callback_on_writable(struct libwebsocket_context *context,
1927                                                        struct libwebsocket *wsi)
1928 {
1929         int n;
1930
1931         for (n = 0; n < context->fds_count; n++)
1932                 if (context->fds[n].fd == wsi->sock) {
1933                         context->fds[n].events |= POLLOUT;
1934                         n = context->fds_count;
1935                 }
1936
1937         /* external POLL support via protocol 0 */
1938         context->protocols[0].callback(context, wsi,
1939                 LWS_CALLBACK_SET_MODE_POLL_FD,
1940                 (void *)(long)wsi->sock, NULL, POLLOUT);
1941
1942         return 1;
1943 }
1944
1945 /**
1946  * libwebsocket_callback_on_writable_all_protocol() - Request a callback for
1947  *                      all connections using the given protocol when it
1948  *                      becomes possible to write to each socket without
1949  *                      blocking in turn.
1950  *
1951  * @protocol:   Protocol whose connections will get callbacks
1952  */
1953
1954 int
1955 libwebsocket_callback_on_writable_all_protocol(
1956                                   const struct libwebsocket_protocols *protocol)
1957 {
1958         struct libwebsocket_context *context = protocol->owning_server;
1959         int n;
1960         int m;
1961         struct libwebsocket *wsi;
1962
1963         for (n = 0; n < FD_HASHTABLE_MODULUS; n++) {
1964
1965                 for (m = 0; m < context->fd_hashtable[n].length; m++) {
1966
1967                         wsi = context->fd_hashtable[n].wsi[m];
1968
1969                         if (wsi->protocol == protocol)
1970                                 libwebsocket_callback_on_writable(context, wsi);
1971                 }
1972         }
1973
1974         return 0;
1975 }
1976
1977 /**
1978  * libwebsocket_set_timeout() - marks the wsi as subject to a timeout
1979  *
1980  * You will not need this unless you are doing something special
1981  *
1982  * @wsi:        Websocket connection instance
1983  * @reason:     timeout reason
1984  * @secs:       how many seconds
1985  */
1986
1987 void
1988 libwebsocket_set_timeout(struct libwebsocket *wsi,
1989                                           enum pending_timeout reason, int secs)
1990 {
1991         struct timeval tv;
1992
1993         gettimeofday(&tv, NULL);
1994
1995         wsi->pending_timeout_limit = tv.tv_sec + secs;
1996         wsi->pending_timeout = reason;
1997 }
1998
1999
2000 /**
2001  * libwebsocket_get_socket_fd() - returns the socket file descriptor
2002  *
2003  * You will not need this unless you are doing something special
2004  *
2005  * @wsi:        Websocket connection instance
2006  */
2007
2008 int
2009 libwebsocket_get_socket_fd(struct libwebsocket *wsi)
2010 {
2011         return wsi->sock;
2012 }
2013
2014 /**
2015  * libwebsocket_rx_flow_control() - Enable and disable socket servicing for
2016  *                              receieved packets.
2017  *
2018  * If the output side of a server process becomes choked, this allows flow
2019  * control for the input side.
2020  *
2021  * @wsi:        Websocket connection instance to get callback for
2022  * @enable:     0 = disable read servicing for this connection, 1 = enable
2023  */
2024
2025 int
2026 libwebsocket_rx_flow_control(struct libwebsocket *wsi, int enable)
2027 {
2028         struct libwebsocket_context *context = wsi->protocol->owning_server;
2029         int n;
2030
2031         for (n = 0; n < context->fds_count; n++)
2032                 if (context->fds[n].fd == wsi->sock) {
2033                         if (enable)
2034                                 context->fds[n].events |= POLLIN;
2035                         else
2036                                 context->fds[n].events &= ~POLLIN;
2037
2038                         return 0;
2039                 }
2040
2041         if (enable)
2042                 /* external POLL support via protocol 0 */
2043                 context->protocols[0].callback(context, wsi,
2044                         LWS_CALLBACK_SET_MODE_POLL_FD,
2045                         (void *)(long)wsi->sock, NULL, POLLIN);
2046         else
2047                 /* external POLL support via protocol 0 */
2048                 context->protocols[0].callback(context, wsi,
2049                         LWS_CALLBACK_CLEAR_MODE_POLL_FD,
2050                         (void *)(long)wsi->sock, NULL, POLLIN);
2051
2052
2053         fprintf(stderr, "libwebsocket_callback_on_writable "
2054                                                      "unable to find socket\n");
2055         return 1;
2056 }
2057
2058 /**
2059  * libwebsocket_canonical_hostname() - returns this host's hostname
2060  *
2061  * This is typically used by client code to fill in the host parameter
2062  * when making a client connection.  You can only call it after the context
2063  * has been created.
2064  *
2065  * @context:    Websocket context
2066  */
2067
2068
2069 extern const char *
2070 libwebsocket_canonical_hostname(struct libwebsocket_context *context)
2071 {
2072         return (const char *)context->canonical_hostname;
2073 }
2074
2075
2076 static void sigpipe_handler(int x)
2077 {
2078 }
2079
2080 #ifdef LWS_OPENSSL_SUPPORT
2081 static int
2082 OpenSSL_verify_callback(int preverify_ok, X509_STORE_CTX *x509_ctx)
2083 {
2084
2085         SSL *ssl;
2086         int n;
2087         struct libwebsocket_context *context;
2088
2089         ssl = X509_STORE_CTX_get_ex_data(x509_ctx,
2090                 SSL_get_ex_data_X509_STORE_CTX_idx());
2091
2092         /*
2093          * !!! nasty openssl requires the index to come as a library-scope
2094          * static
2095          */
2096         context = SSL_get_ex_data(ssl, openssl_websocket_private_data_index);
2097
2098         n = context->protocols[0].callback(NULL, NULL,
2099                 LWS_CALLBACK_OPENSSL_PERFORM_CLIENT_CERT_VERIFICATION,
2100                                                    x509_ctx, ssl, preverify_ok);
2101
2102         /* convert return code from 0 = OK to 1 = OK */
2103
2104         if (!n)
2105                 n = 1;
2106         else
2107                 n = 0;
2108
2109         return n;
2110 }
2111 #endif
2112
2113
2114 /**
2115  * libwebsocket_create_context() - Create the websocket handler
2116  * @port:       Port to listen on... you can use 0 to suppress listening on
2117  *              any port, that's what you want if you are not running a
2118  *              websocket server at all but just using it as a client
2119  * @interf:  NULL to bind the listen socket to all interfaces, or the
2120  *              interface name, eg, "eth2"
2121  * @protocols:  Array of structures listing supported protocols and a protocol-
2122  *              specific callback for each one.  The list is ended with an
2123  *              entry that has a NULL callback pointer.
2124  *              It's not const because we write the owning_server member
2125  * @extensions: NULL or array of libwebsocket_extension structs listing the
2126  *              extensions this context supports
2127  * @ssl_cert_filepath:  If libwebsockets was compiled to use ssl, and you want
2128  *                      to listen using SSL, set to the filepath to fetch the
2129  *                      server cert from, otherwise NULL for unencrypted
2130  * @ssl_private_key_filepath: filepath to private key if wanting SSL mode,
2131  *                      else ignored
2132  * @gid:        group id to change to after setting listen socket, or -1.
2133  * @uid:        user id to change to after setting listen socket, or -1.
2134  * @options:    0, or LWS_SERVER_OPTION_DEFEAT_CLIENT_MASK
2135  *
2136  *      This function creates the listening socket and takes care
2137  *      of all initialization in one step.
2138  *
2139  *      After initialization, it returns a struct libwebsocket_context * that
2140  *      represents this server.  After calling, user code needs to take care
2141  *      of calling libwebsocket_service() with the context pointer to get the
2142  *      server's sockets serviced.  This can be done in the same process context
2143  *      or a forked process, or another thread,
2144  *
2145  *      The protocol callback functions are called for a handful of events
2146  *      including http requests coming in, websocket connections becoming
2147  *      established, and data arriving; it's also called periodically to allow
2148  *      async transmission.
2149  *
2150  *      HTTP requests are sent always to the FIRST protocol in @protocol, since
2151  *      at that time websocket protocol has not been negotiated.  Other
2152  *      protocols after the first one never see any HTTP callack activity.
2153  *
2154  *      The server created is a simple http server by default; part of the
2155  *      websocket standard is upgrading this http connection to a websocket one.
2156  *
2157  *      This allows the same server to provide files like scripts and favicon /
2158  *      images or whatever over http and dynamic data over websockets all in
2159  *      one place; they're all handled in the user callback.
2160  */
2161
2162 struct libwebsocket_context *
2163 libwebsocket_create_context(int port, const char *interf,
2164                                struct libwebsocket_protocols *protocols,
2165                                struct libwebsocket_extension *extensions,
2166                                const char *ssl_cert_filepath,
2167                                const char *ssl_private_key_filepath,
2168                                int gid, int uid, unsigned int options)
2169 {
2170         int n;
2171         int sockfd = 0;
2172         int fd;
2173         struct sockaddr_in serv_addr, cli_addr;
2174         int opt = 1;
2175         struct libwebsocket_context *context = NULL;
2176         unsigned int slen;
2177         char *p;
2178         char hostname[1024];
2179         struct hostent *he;
2180         struct libwebsocket *wsi;
2181
2182 #ifdef LWS_OPENSSL_SUPPORT
2183         SSL_METHOD *method;
2184         char ssl_err_buf[512];
2185 #endif
2186
2187 #ifdef _WIN32
2188         {
2189                 WORD wVersionRequested;
2190                 WSADATA wsaData;
2191                 int err;
2192
2193                 /* Use the MAKEWORD(lowbyte, highbyte) macro from Windef.h */
2194                 wVersionRequested = MAKEWORD(2, 2);
2195
2196                 err = WSAStartup(wVersionRequested, &wsaData);
2197                 if (err != 0) {
2198                         /* Tell the user that we could not find a usable */
2199                         /* Winsock DLL.                                  */
2200                         fprintf(stderr, "WSAStartup failed with error: %d\n",
2201                                                                            err);
2202                         return NULL;
2203                 }
2204         }
2205 #endif
2206
2207
2208         context = malloc(sizeof(struct libwebsocket_context));
2209         if (!context) {
2210                 fprintf(stderr, "No memory for websocket context\n");
2211                 return NULL;
2212         }
2213         context->protocols = protocols;
2214         context->listen_port = port;
2215         context->http_proxy_port = 0;
2216         context->http_proxy_address[0] = '\0';
2217         context->options = options;
2218         context->fds_count = 0;
2219         context->extensions = extensions;
2220
2221 #ifdef WIN32
2222         context->fd_random = 0;
2223 #else
2224         context->fd_random = open(SYSTEM_RANDOM_FILEPATH, O_RDONLY);
2225         if (context->fd_random < 0) {
2226                 fprintf(stderr, "Unable to open random device %s %d\n",
2227                                     SYSTEM_RANDOM_FILEPATH, context->fd_random);
2228                 return NULL;
2229         }
2230 #endif
2231
2232 #ifdef LWS_OPENSSL_SUPPORT
2233         context->use_ssl = 0;
2234         context->ssl_ctx = NULL;
2235         context->ssl_client_ctx = NULL;
2236         openssl_websocket_private_data_index = 0;
2237 #endif
2238         /* find canonical hostname */
2239
2240         hostname[(sizeof hostname) - 1] = '\0';
2241         gethostname(hostname, (sizeof hostname) - 1);
2242         he = gethostbyname(hostname);
2243         if (he) {
2244                 strncpy(context->canonical_hostname, he->h_name,
2245                                         sizeof context->canonical_hostname - 1);
2246                 context->canonical_hostname[
2247                                 sizeof context->canonical_hostname - 1] = '\0';
2248         } else
2249                 strncpy(context->canonical_hostname, hostname,
2250                                         sizeof context->canonical_hostname - 1);
2251
2252         /* split the proxy ads:port if given */
2253
2254         p = getenv("http_proxy");
2255         if (p) {
2256                 strncpy(context->http_proxy_address, p,
2257                                         sizeof context->http_proxy_address - 1);
2258                 context->http_proxy_address[
2259                                  sizeof context->http_proxy_address - 1] = '\0';
2260
2261                 p = strchr(context->http_proxy_address, ':');
2262                 if (p == NULL) {
2263                         fprintf(stderr, "http_proxy needs to be ads:port\n");
2264                         return NULL;
2265                 }
2266                 *p = '\0';
2267                 context->http_proxy_port = atoi(p + 1);
2268
2269                 fprintf(stderr, "Using proxy %s:%u\n",
2270                                 context->http_proxy_address,
2271                                                       context->http_proxy_port);
2272         }
2273
2274         if (port) {
2275
2276 #ifdef LWS_OPENSSL_SUPPORT
2277                 context->use_ssl = ssl_cert_filepath != NULL &&
2278                                                ssl_private_key_filepath != NULL;
2279                 if (context->use_ssl)
2280                         fprintf(stderr, " Compiled with SSL support, "
2281                                                                   "using it\n");
2282                 else
2283                         fprintf(stderr, " Compiled with SSL support, "
2284                                                               "not using it\n");
2285
2286 #else
2287                 if (ssl_cert_filepath != NULL &&
2288                                              ssl_private_key_filepath != NULL) {
2289                         fprintf(stderr, " Not compiled for OpenSSl support!\n");
2290                         return NULL;
2291                 }
2292                 fprintf(stderr, " Compiled without SSL support, "
2293                                                        "serving unencrypted\n");
2294 #endif
2295         }
2296
2297         /* ignore SIGPIPE */
2298 #ifdef WIN32
2299 #else
2300         signal(SIGPIPE, sigpipe_handler);
2301 #endif
2302
2303
2304 #ifdef LWS_OPENSSL_SUPPORT
2305
2306         /* basic openssl init */
2307
2308         SSL_library_init();
2309
2310         OpenSSL_add_all_algorithms();
2311         SSL_load_error_strings();
2312
2313         openssl_websocket_private_data_index =
2314                 SSL_get_ex_new_index(0, "libwebsockets", NULL, NULL, NULL);
2315
2316         /*
2317          * Firefox insists on SSLv23 not SSLv3
2318          * Konq disables SSLv2 by default now, SSLv23 works
2319          */
2320
2321         method = (SSL_METHOD *)SSLv23_server_method();
2322         if (!method) {
2323                 fprintf(stderr, "problem creating ssl method: %s\n",
2324                         ERR_error_string(ERR_get_error(), ssl_err_buf));
2325                 return NULL;
2326         }
2327         context->ssl_ctx = SSL_CTX_new(method); /* create context */
2328         if (!context->ssl_ctx) {
2329                 fprintf(stderr, "problem creating ssl context: %s\n",
2330                         ERR_error_string(ERR_get_error(), ssl_err_buf));
2331                 return NULL;
2332         }
2333
2334         /* client context */
2335         if (port == CONTEXT_PORT_NO_LISTEN)
2336         {
2337                 method = (SSL_METHOD *)SSLv23_client_method();
2338                 if (!method) {
2339                         fprintf(stderr, "problem creating ssl method: %s\n",
2340                                 ERR_error_string(ERR_get_error(), ssl_err_buf));
2341                         return NULL;
2342                 }
2343                 /* create context */
2344                 context->ssl_client_ctx = SSL_CTX_new(method);
2345                 if (!context->ssl_client_ctx) {
2346                         fprintf(stderr, "problem creating ssl context: %s\n",
2347                                 ERR_error_string(ERR_get_error(), ssl_err_buf));
2348                         return NULL;
2349                 }
2350
2351                 /* openssl init for cert verification (for client sockets) */
2352
2353                 if (!SSL_CTX_load_verify_locations(
2354                                         context->ssl_client_ctx, NULL,
2355                                                       LWS_OPENSSL_CLIENT_CERTS))
2356                         fprintf(stderr,
2357                             "Unable to load SSL Client certs from %s "
2358                             "(set by --with-client-cert-dir= in configure) -- "
2359                                 " client ssl isn't going to work",
2360                                                       LWS_OPENSSL_CLIENT_CERTS);
2361
2362                 /*
2363                  * callback allowing user code to load extra verification certs
2364                  * helping the client to verify server identity
2365                  */
2366
2367                 context->protocols[0].callback(context, NULL,
2368                         LWS_CALLBACK_OPENSSL_LOAD_EXTRA_CLIENT_VERIFY_CERTS,
2369                         context->ssl_client_ctx, NULL, 0);
2370         }
2371         /* as a server, are we requiring clients to identify themselves? */
2372
2373         if (options & LWS_SERVER_OPTION_REQUIRE_VALID_OPENSSL_CLIENT_CERT) {
2374
2375                 /* absolutely require the client cert */
2376
2377                 SSL_CTX_set_verify(context->ssl_ctx,
2378                        SSL_VERIFY_PEER | SSL_VERIFY_FAIL_IF_NO_PEER_CERT,
2379                                                        OpenSSL_verify_callback);
2380
2381                 /*
2382                  * give user code a chance to load certs into the server
2383                  * allowing it to verify incoming client certs
2384                  */
2385
2386                 context->protocols[0].callback(context, NULL,
2387                         LWS_CALLBACK_OPENSSL_LOAD_EXTRA_SERVER_VERIFY_CERTS,
2388                                                      context->ssl_ctx, NULL, 0);
2389         }
2390
2391         if (context->use_ssl) {
2392
2393                 /* openssl init for server sockets */
2394
2395                 /* set the local certificate from CertFile */
2396                 n = SSL_CTX_use_certificate_file(context->ssl_ctx,
2397                                         ssl_cert_filepath, SSL_FILETYPE_PEM);
2398                 if (n != 1) {
2399                         fprintf(stderr, "problem getting cert '%s': %s\n",
2400                                 ssl_cert_filepath,
2401                                 ERR_error_string(ERR_get_error(), ssl_err_buf));
2402                         return NULL;
2403                 }
2404                 /* set the private key from KeyFile */
2405                 if (SSL_CTX_use_PrivateKey_file(context->ssl_ctx,
2406                              ssl_private_key_filepath, SSL_FILETYPE_PEM) != 1) {
2407                         fprintf(stderr, "ssl problem getting key '%s': %s\n",
2408                                                 ssl_private_key_filepath,
2409                                 ERR_error_string(ERR_get_error(), ssl_err_buf));
2410                         return NULL;
2411                 }
2412                 /* verify private key */
2413                 if (!SSL_CTX_check_private_key(context->ssl_ctx)) {
2414                         fprintf(stderr, "Private SSL key doesn't match cert\n");
2415                         return NULL;
2416                 }
2417
2418                 /* SSL is happy and has a cert it's content with */
2419         }
2420 #endif
2421
2422         /* selftest */
2423
2424         if (lws_b64_selftest())
2425                 return NULL;
2426
2427         /* fd hashtable init */
2428
2429         for (n = 0; n < FD_HASHTABLE_MODULUS; n++)
2430                 context->fd_hashtable[n].length = 0;
2431
2432         /* set up our external listening socket we serve on */
2433
2434         if (port) {
2435
2436                 sockfd = socket(AF_INET, SOCK_STREAM, 0);
2437                 if (sockfd < 0) {
2438                         fprintf(stderr, "ERROR opening socket");
2439                         return NULL;
2440                 }
2441
2442                 /* allow us to restart even if old sockets in TIME_WAIT */
2443                 setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt));
2444
2445
2446                 /* Disable Nagle */
2447                 opt = 1;
2448                 setsockopt(sockfd, SOL_TCP, TCP_NODELAY, &opt, sizeof(opt));
2449
2450                 bzero((char *) &serv_addr, sizeof(serv_addr));
2451                 serv_addr.sin_family = AF_INET;
2452                 if (interf == NULL)
2453                         serv_addr.sin_addr.s_addr = INADDR_ANY;
2454                 else
2455                         interface_to_sa(interf, &serv_addr,
2456                                                 sizeof(serv_addr));
2457                 serv_addr.sin_port = htons(port);
2458
2459                 n = bind(sockfd, (struct sockaddr *) &serv_addr,
2460                                                              sizeof(serv_addr));
2461                 if (n < 0) {
2462                         fprintf(stderr, "ERROR on binding to port %d (%d %d)\n",
2463                                                                 port, n, errno);
2464                         return NULL;
2465                 }
2466
2467                 wsi = malloc(sizeof(struct libwebsocket));
2468                 memset(wsi, 0, sizeof (struct libwebsocket));
2469                 wsi->sock = sockfd;
2470                 wsi->count_active_extensions = 0;
2471                 wsi->mode = LWS_CONNMODE_SERVER_LISTENER;
2472                 insert_wsi(context, wsi);
2473
2474                 listen(sockfd, 5);
2475                 fprintf(stderr, " Listening on port %d\n", port);
2476
2477                 /* list in the internal poll array */
2478
2479                 context->fds[context->fds_count].fd = sockfd;
2480                 context->fds[context->fds_count++].events = POLLIN;
2481
2482                 /* external POLL support via protocol 0 */
2483                 context->protocols[0].callback(context, wsi,
2484                         LWS_CALLBACK_ADD_POLL_FD,
2485                         (void *)(long)sockfd, NULL, POLLIN);
2486
2487         }
2488
2489         /* drop any root privs for this process */
2490 #ifdef WIN32
2491 #else
2492         if (gid != -1)
2493                 if (setgid(gid))
2494                         fprintf(stderr, "setgid: %s\n", strerror(errno));
2495         if (uid != -1)
2496                 if (setuid(uid))
2497                         fprintf(stderr, "setuid: %s\n", strerror(errno));
2498 #endif
2499
2500         /* set up our internal broadcast trigger sockets per-protocol */
2501
2502         for (context->count_protocols = 0;
2503                         protocols[context->count_protocols].callback;
2504                                                    context->count_protocols++) {
2505                 protocols[context->count_protocols].owning_server = context;
2506                 protocols[context->count_protocols].protocol_index =
2507                                                        context->count_protocols;
2508
2509                 fd = socket(AF_INET, SOCK_STREAM, 0);
2510                 if (fd < 0) {
2511                         fprintf(stderr, "ERROR opening socket");
2512                         return NULL;
2513                 }
2514
2515                 /* allow us to restart even if old sockets in TIME_WAIT */
2516                 setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt));
2517
2518                 bzero((char *) &serv_addr, sizeof(serv_addr));
2519                 serv_addr.sin_family = AF_INET;
2520                 serv_addr.sin_addr.s_addr = inet_addr("127.0.0.1");
2521                 serv_addr.sin_port = 0; /* pick the port for us */
2522
2523                 n = bind(fd, (struct sockaddr *) &serv_addr, sizeof(serv_addr));
2524                 if (n < 0) {
2525                         fprintf(stderr, "ERROR on binding to port %d (%d %d)\n",
2526                                                                 port, n, errno);
2527                         return NULL;
2528                 }
2529
2530                 slen = sizeof cli_addr;
2531                 n = getsockname(fd, (struct sockaddr *)&cli_addr, &slen);
2532                 if (n < 0) {
2533                         fprintf(stderr, "getsockname failed\n");
2534                         return NULL;
2535                 }
2536                 protocols[context->count_protocols].broadcast_socket_port =
2537                                                        ntohs(cli_addr.sin_port);
2538                 listen(fd, 5);
2539
2540                 debug("  Protocol %s broadcast socket %d\n",
2541                                 protocols[context->count_protocols].name,
2542                                                       ntohs(cli_addr.sin_port));
2543
2544                 /* dummy wsi per broadcast proxy socket */
2545
2546                 wsi = malloc(sizeof(struct libwebsocket));
2547                 memset(wsi, 0, sizeof (struct libwebsocket));
2548                 wsi->sock = fd;
2549                 wsi->mode = LWS_CONNMODE_BROADCAST_PROXY_LISTENER;
2550                 wsi->count_active_extensions = 0;
2551                 /* note which protocol we are proxying */
2552                 wsi->protocol_index_for_broadcast_proxy =
2553                                                        context->count_protocols;
2554                 insert_wsi(context, wsi);
2555
2556                 /* list in internal poll array */
2557
2558                 context->fds[context->fds_count].fd = fd;
2559                 context->fds[context->fds_count].events = POLLIN;
2560                 context->fds[context->fds_count].revents = 0;
2561                 context->fds_count++;
2562
2563                 /* external POLL support via protocol 0 */
2564                 context->protocols[0].callback(context, wsi,
2565                         LWS_CALLBACK_ADD_POLL_FD,
2566                         (void *)(long)fd, NULL, POLLIN);
2567         }
2568
2569         return context;
2570 }
2571
2572
2573 #ifndef LWS_NO_FORK
2574
2575 /**
2576  * libwebsockets_fork_service_loop() - Optional helper function forks off
2577  *                                a process for the websocket server loop.
2578  *                              You don't have to use this but if not, you
2579  *                              have to make sure you are calling
2580  *                              libwebsocket_service periodically to service
2581  *                              the websocket traffic
2582  * @context:    server context returned by creation function
2583  */
2584
2585 int
2586 libwebsockets_fork_service_loop(struct libwebsocket_context *context)
2587 {
2588         int fd;
2589         struct sockaddr_in cli_addr;
2590         int n;
2591         int p;
2592
2593         n = fork();
2594         if (n < 0)
2595                 return n;
2596
2597         if (!n) {
2598
2599                 /* main process context */
2600
2601                 /*
2602                  * set up the proxy sockets to allow broadcast from
2603                  * service process context
2604                  */
2605
2606                 for (p = 0; p < context->count_protocols; p++) {
2607                         fd = socket(AF_INET, SOCK_STREAM, 0);
2608                         if (fd < 0) {
2609                                 fprintf(stderr, "Unable to create socket\n");
2610                                 return -1;
2611                         }
2612                         cli_addr.sin_family = AF_INET;
2613                         cli_addr.sin_port = htons(
2614                              context->protocols[p].broadcast_socket_port);
2615                         cli_addr.sin_addr.s_addr = inet_addr("127.0.0.1");
2616                         n = connect(fd, (struct sockaddr *)&cli_addr,
2617                                                                sizeof cli_addr);
2618                         if (n < 0) {
2619                                 fprintf(stderr, "Unable to connect to "
2620                                                 "broadcast socket %d, %s\n",
2621                                                 n, strerror(errno));
2622                                 return -1;
2623                         }
2624
2625                         context->protocols[p].broadcast_socket_user_fd = fd;
2626                 }
2627
2628                 return 0;
2629         }
2630
2631         /* we want a SIGHUP when our parent goes down */
2632         prctl(PR_SET_PDEATHSIG, SIGHUP);
2633
2634         /* in this forked process, sit and service websocket connections */
2635
2636         while (1)
2637                 if (libwebsocket_service(context, 1000))
2638                         return -1;
2639
2640         return 0;
2641 }
2642
2643 #endif
2644
2645 /**
2646  * libwebsockets_get_protocol() - Returns a protocol pointer from a websocket
2647  *                                connection.
2648  * @wsi:        pointer to struct websocket you want to know the protocol of
2649  *
2650  *
2651  *      This is useful to get the protocol to broadcast back to from inside
2652  * the callback.
2653  */
2654
2655 const struct libwebsocket_protocols *
2656 libwebsockets_get_protocol(struct libwebsocket *wsi)
2657 {
2658         return wsi->protocol;
2659 }
2660
2661 /**
2662  * libwebsockets_broadcast() - Sends a buffer to the callback for all active
2663  *                                connections of the given protocol.
2664  * @protocol:   pointer to the protocol you will broadcast to all members of
2665  * @buf:  buffer containing the data to be broadcase.  NOTE: this has to be
2666  *              allocated with LWS_SEND_BUFFER_PRE_PADDING valid bytes before
2667  *              the pointer and LWS_SEND_BUFFER_POST_PADDING afterwards in the
2668  *              case you are calling this function from callback context.
2669  * @len:        length of payload data in buf, starting from buf.
2670  *
2671  *      This function allows bulk sending of a packet to every connection using
2672  * the given protocol.  It does not send the data directly; instead it calls
2673  * the callback with a reason type of LWS_CALLBACK_BROADCAST.  If the callback
2674  * wants to actually send the data for that connection, the callback itself
2675  * should call libwebsocket_write().
2676  *
2677  * libwebsockets_broadcast() can be called from another fork context without
2678  * having to take any care about data visibility between the processes, it'll
2679  * "just work".
2680  */
2681
2682
2683 int
2684 libwebsockets_broadcast(const struct libwebsocket_protocols *protocol,
2685                                                  unsigned char *buf, size_t len)
2686 {
2687         struct libwebsocket_context *context = protocol->owning_server;
2688         int n;
2689         int m;
2690         struct libwebsocket * wsi;
2691
2692         if (!protocol->broadcast_socket_user_fd) {
2693                 /*
2694                  * We are either running unforked / flat, or we are being
2695                  * called from poll thread context
2696                  * eg, from a callback.  In that case don't use sockets for
2697                  * broadcast IPC (since we can't open a socket connection to
2698                  * a socket listening on our own thread) but directly do the
2699                  * send action.
2700                  *
2701                  * Locking is not needed because we are by definition being
2702                  * called in the poll thread context and are serialized.
2703                  */
2704
2705                 for (n = 0; n < FD_HASHTABLE_MODULUS; n++) {
2706
2707                         for (m = 0; m < context->fd_hashtable[n].length; m++) {
2708
2709                                 wsi = context->fd_hashtable[n].wsi[m];
2710
2711                                 if (wsi->mode != LWS_CONNMODE_WS_SERVING)
2712                                         continue;
2713
2714                                 /*
2715                                  * never broadcast to
2716                                  * non-established connections
2717                                  */
2718                                 if (wsi->state != WSI_STATE_ESTABLISHED)
2719                                         continue;
2720
2721                                 /* only broadcast to guys using
2722                                  * requested protocol
2723                                  */
2724                                 if (wsi->protocol != protocol)
2725                                         continue;
2726
2727                                 wsi->protocol->callback(context, wsi,
2728                                          LWS_CALLBACK_BROADCAST,
2729                                          wsi->user_space,
2730                                          buf, len);
2731                         }
2732                 }
2733
2734                 return 0;
2735         }
2736
2737         /*
2738          * We're being called from a different process context than the server
2739          * loop.  Instead of broadcasting directly, we send our
2740          * payload on a socket to do the IPC; the server process will serialize
2741          * the broadcast action in its main poll() loop.
2742          *
2743          * There's one broadcast socket listening for each protocol supported
2744          * set up when the websocket server initializes
2745          */
2746
2747         n = send(protocol->broadcast_socket_user_fd, buf, len, MSG_NOSIGNAL);
2748
2749         return n;
2750 }
2751
2752 int
2753 libwebsocket_is_final_fragment(struct libwebsocket *wsi)
2754 {
2755         return wsi->final;
2756 }