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