lib/libwebsockets.c

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