lib/client.c

   1 /*
   2  * libwebsockets - small server side websockets and web server implementation
   3  *
   4  * Copyright (C) 2010-2014 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 int
  25 lws_handshake_client(struct lws *wsi, unsigned char **buf, size_t len)
  26 {
  27         int m;
  28
  29         switch (wsi->mode) {
  30         case LWSCM_WSCL_WAITING_PROXY_REPLY:
  31         case LWSCM_WSCL_ISSUE_HANDSHAKE:
  32         case LWSCM_WSCL_WAITING_SERVER_REPLY:
  33         case LWSCM_WSCL_WAITING_EXTENSION_CONNECT:
  34         case LWSCM_WS_CLIENT:
  35                 while (len) {
  36                         /*
  37                          * we were accepting input but now we stopped doing so
  38                          */
  39                         if (!(wsi->rxflow_change_to & LWS_RXFLOW_ALLOW)) {
  40                                 lwsl_debug("%s: caching %d\n", __func__, len);
  41                                 lws_rxflow_cache(wsi, *buf, 0, len);
  42                                 return 0;
  43                         }
  44                         if (wsi->u.ws.rx_draining_ext) {
  45                                 m = lws_rx_sm(wsi, 0);
  46                                 if (m < 0)
  47                                         return -1;
  48                                 continue;
  49                         }
  50                         /* account for what we're using in rxflow buffer */
  51                         if (wsi->rxflow_buffer)
  52                                 wsi->rxflow_pos++;
  53
  54                         if (lws_client_rx_sm(wsi, *(*buf)++)) {
  55                                 lwsl_debug("client_rx_sm exited\n");
  56                                 return -1;
  57                         }
  58                         len--;
  59                 }
  60                 lwsl_debug("%s: finished with %d\n", __func__, len);
  61                 return 0;
  62         default:
  63                 break;
  64         }
  65
  66         return 0;
  67 }
  68
  69 int
  70 lws_client_socket_service(struct lws_context *context, struct lws *wsi,
  71                           struct lws_pollfd *pollfd)
  72 {
  73         struct lws_context_per_thread *pt = &context->pt[(int)wsi->tsi];
  74         char *p = (char *)&pt->serv_buf[0];
  75         char *sb = p;
  76         unsigned char c;
  77         int n, len;
  78
  79         switch (wsi->mode) {
  80
  81         case LWSCM_WSCL_WAITING_CONNECT:
  82
  83                 /*
  84                  * we are under PENDING_TIMEOUT_SENT_CLIENT_HANDSHAKE
  85                  * timeout protection set in client-handshake.c
  86                  */
  87
  88                 if (!lws_client_connect_2(wsi)) {
  89                         /* closed */
  90                         lwsl_client("closed\n");
  91                         return -1;
  92                 }
  93
  94                 /* either still pending connection, or changed mode */
  95                 return 0;
  96
  97         case LWSCM_WSCL_WAITING_PROXY_REPLY:
  98
  99                 /* handle proxy hung up on us */
 100
 101                 if (pollfd->revents & LWS_POLLHUP) {
 102
 103                         lwsl_warn("Proxy connection %p (fd=%d) dead\n",
 104                                   (void *)wsi, pollfd->fd);
 105
 106                         lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS);
 107                         return 0;
 108                 }
 109
 110                 n = recv(wsi->sock, sb, LWS_MAX_SOCKET_IO_BUF, 0);
 111                 if (n < 0) {
 112                         if (LWS_ERRNO == LWS_EAGAIN) {
 113                                 lwsl_debug("Proxy read returned EAGAIN... retrying\n");
 114                                 return 0;
 115                         }
 116
 117                         lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS);
 118                         lwsl_err("ERROR reading from proxy socket\n");
 119                         return 0;
 120                 }
 121
 122                 pt->serv_buf[13] = '\0';
 123                 if (strcmp(sb, "HTTP/1.0 200 ") &&
 124                     strcmp(sb, "HTTP/1.1 200 ")) {
 125                         lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS);
 126                         lwsl_err("ERROR proxy: %s\n", sb);
 127                         return 0;
 128                 }
 129
 130                 /* clear his proxy connection timeout */
 131
 132                 lws_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
 133
 134                 /* fallthru */
 135
 136         case LWSCM_WSCL_ISSUE_HANDSHAKE:
 137
 138                 /*
 139                  * we are under PENDING_TIMEOUT_SENT_CLIENT_HANDSHAKE
 140                  * timeout protection set in client-handshake.c
 141                  *
 142                  * take care of our lws_callback_on_writable
 143                  * happening at a time when there's no real connection yet
 144                  */
 145                 if (lws_change_pollfd(wsi, LWS_POLLOUT, 0))
 146                         return -1;
 147
 148 #ifdef LWS_OPENSSL_SUPPORT
 149                 /* we can retry this... just cook the SSL BIO the first time */
 150
 151                 if (wsi->use_ssl && !wsi->ssl) {
 152 #if defined(CYASSL_SNI_HOST_NAME) || defined(WOLFSSL_SNI_HOST_NAME) || defined(SSL_CTRL_SET_TLSEXT_HOSTNAME)
 153                         const char *hostname = lws_hdr_simple_ptr(wsi,
 154                                                 _WSI_TOKEN_CLIENT_HOST);
 155 #endif
 156
 157                         wsi->ssl = SSL_new(context->ssl_client_ctx);
 158 #ifndef USE_WOLFSSL
 159                         SSL_set_mode(wsi->ssl,
 160                                         SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER);
 161 #endif
 162                         /*
 163                          * use server name indication (SNI), if supported,
 164                          * when establishing connection
 165                          */
 166 #ifdef USE_WOLFSSL
 167 #ifdef USE_OLD_CYASSL
 168 #ifdef CYASSL_SNI_HOST_NAME
 169                         CyaSSL_UseSNI(wsi->ssl, CYASSL_SNI_HOST_NAME,
 170                                 hostname, strlen(hostname));
 171 #endif
 172 #else
 173 #ifdef WOLFSSL_SNI_HOST_NAME
 174                         wolfSSL_UseSNI(wsi->ssl, WOLFSSL_SNI_HOST_NAME,
 175                                 hostname, strlen(hostname));
 176 #endif
 177 #endif
 178 #else
 179 #ifdef SSL_CTRL_SET_TLSEXT_HOSTNAME
 180                         SSL_set_tlsext_host_name(wsi->ssl, hostname);
 181 #endif
 182 #endif
 183
 184 #ifdef USE_WOLFSSL
 185                         /*
 186                          * wolfSSL/CyaSSL does certificate verification differently
 187                          * from OpenSSL.
 188                          * If we should ignore the certificate, we need to set
 189                          * this before SSL_new and SSL_connect is called.
 190                          * Otherwise the connect will simply fail with error
 191                          * code -155
 192                          */
 193 #ifdef USE_OLD_CYASSL
 194                         if (wsi->use_ssl == 2)
 195                                 CyaSSL_set_verify(wsi->ssl,
 196                                                         SSL_VERIFY_NONE, NULL);
 197 #else
 198                         if (wsi->use_ssl == 2)
 199                                 wolfSSL_set_verify(wsi->ssl,
 200                                                         SSL_VERIFY_NONE, NULL);
 201 #endif
 202 #endif /* USE_WOLFSSL */
 203
 204                         wsi->client_bio =
 205                                 BIO_new_socket(wsi->sock, BIO_NOCLOSE);
 206                         SSL_set_bio(wsi->ssl, wsi->client_bio, wsi->client_bio);
 207
 208 #ifdef USE_WOLFSSL
 209 #ifdef USE_OLD_CYASSL
 210                         CyaSSL_set_using_nonblock(wsi->ssl, 1);
 211 #else
 212                         wolfSSL_set_using_nonblock(wsi->ssl, 1);
 213 #endif
 214 #else
 215                         BIO_set_nbio(wsi->client_bio, 1); /* nonblocking */
 216 #endif
 217
 218                         SSL_set_ex_data(wsi->ssl,
 219                                         openssl_websocket_private_data_index,
 220                                                                        context);
 221                 }
 222
 223                 if (wsi->use_ssl) {
 224                         lws_latency_pre(context, wsi);
 225                         n = SSL_connect(wsi->ssl);
 226                         lws_latency(context, wsi,
 227                           "SSL_connect LWSCM_WSCL_ISSUE_HANDSHAKE", n, n > 0);
 228
 229                         if (n < 0) {
 230                                 n = SSL_get_error(wsi->ssl, n);
 231
 232                                 if (n == SSL_ERROR_WANT_READ)
 233                                         goto some_wait;
 234
 235                                 if (n == SSL_ERROR_WANT_WRITE) {
 236                                         /*
 237                                          * wants us to retry connect due to
 238                                          * state of the underlying ssl layer...
 239                                          * but since it may be stalled on
 240                                          * blocked write, no incoming data may
 241                                          * arrive to trigger the retry.
 242                                          * Force (possibly many times if the SSL
 243                                          * state persists in returning the
 244                                          * condition code, but other sockets
 245                                          * are getting serviced inbetweentimes)
 246                                          * us to get called back when writable.
 247                                          */
 248                                         lwsl_info("%s: WANT_WRITE... retrying\n", __func__);
 249                                         lws_callback_on_writable(wsi);
 250 some_wait:
 251                                         wsi->mode = LWSCM_WSCL_WAITING_SSL;
 252
 253                                         return 0; /* no error */
 254                                 }
 255                                 n = -1;
 256                         }
 257
 258                         if (n <= 0) {
 259                                 /*
 260                                  * retry if new data comes until we
 261                                  * run into the connection timeout or win
 262                                  */
 263                                 n = ERR_get_error();
 264                                 if (n != SSL_ERROR_NONE) {
 265                                         lwsl_err("SSL connect error %lu: %s\n",
 266                                                 n, ERR_error_string(n, sb));
 267                                         return 0;
 268                                 }
 269                         }
 270                 } else
 271                         wsi->ssl = NULL;
 272
 273                 /* fallthru */
 274
 275         case LWSCM_WSCL_WAITING_SSL:
 276
 277                 if (wsi->use_ssl) {
 278                         if (wsi->mode == LWSCM_WSCL_WAITING_SSL) {
 279                                 lws_latency_pre(context, wsi);
 280                                 n = SSL_connect(wsi->ssl);
 281                                 lws_latency(context, wsi,
 282                                             "SSL_connect LWSCM_WSCL_WAITING_SSL",
 283                                             n, n > 0);
 284
 285                                 if (n < 0) {
 286                                         n = SSL_get_error(wsi->ssl, n);
 287
 288                                         if (n == SSL_ERROR_WANT_READ)
 289                                                 goto some_wait;
 290
 291                                         if (n == SSL_ERROR_WANT_WRITE) {
 292                                                 /*
 293                                                  * wants us to retry connect due to
 294                                                  * state of the underlying ssl layer...
 295                                                  * but since it may be stalled on
 296                                                  * blocked write, no incoming data may
 297                                                  * arrive to trigger the retry.
 298                                                  * Force (possibly many times if the SSL
 299                                                  * state persists in returning the
 300                                                  * condition code, but other sockets
 301                                                  * are getting serviced inbetweentimes)
 302                                                  * us to get called back when writable.
 303                                                  */
 304                                                 lwsl_info("SSL_connect WANT_WRITE... retrying\n");
 305                                                 lws_callback_on_writable(wsi);
 306
 307                                                 goto some_wait;
 308                                         }
 309                                         n = -1;
 310                                 }
 311
 312                                 if (n <= 0) {
 313                                         /*
 314                                          * retry if new data comes until we
 315                                          * run into the connection timeout or win
 316                                          */
 317                                         n = ERR_get_error();
 318                                         if (n != SSL_ERROR_NONE) {
 319                                                 lwsl_err("SSL connect error %lu: %s\n",
 320                                                          n, ERR_error_string(n, sb));
 321                                                 return 0;
 322                                         }
 323                                 }
 324                         }
 325
 326                         #ifndef USE_WOLFSSL
 327                         /*
 328                          * See comment above about wolfSSL certificate
 329                          * verification
 330                          */
 331                         lws_latency_pre(context, wsi);
 332                         n = SSL_get_verify_result(wsi->ssl);
 333                         lws_latency(context, wsi,
 334                                 "SSL_get_verify_result LWS_CONNMODE..HANDSHAKE",
 335                                                                       n, n > 0);
 336
 337                         if (n != X509_V_OK) {
 338                                 if ((n == X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT ||
 339                                      n == X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN) && wsi->use_ssl == 2) {
 340                                         lwsl_notice("accepting self-signed certificate\n");
 341                                 } else {
 342                                         lwsl_err("server's cert didn't look good, X509_V_ERR = %d: %s\n",
 343                                                  n, ERR_error_string(n, sb));
 344                                         lws_close_free_wsi(wsi,
 345                                                 LWS_CLOSE_STATUS_NOSTATUS);
 346                                         return 0;
 347                                 }
 348                         }
 349 #endif /* USE_WOLFSSL */
 350                 } else
 351                         wsi->ssl = NULL;
 352 #endif
 353
 354                 wsi->mode = LWSCM_WSCL_ISSUE_HANDSHAKE2;
 355                 lws_set_timeout(wsi, PENDING_TIMEOUT_AWAITING_CLIENT_HS_SEND,
 356                                 context->timeout_secs);
 357
 358                 /* fallthru */
 359
 360         case LWSCM_WSCL_ISSUE_HANDSHAKE2:
 361                 p = lws_generate_client_handshake(wsi, p);
 362                 if (p == NULL) {
 363                         lwsl_err("Failed to generate handshake for client\n");
 364                         lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS);
 365                         return 0;
 366                 }
 367
 368                 /* send our request to the server */
 369
 370                 lws_latency_pre(context, wsi);
 371
 372                 n = lws_ssl_capable_write(wsi, (unsigned char *)sb, p - sb);
 373                 lws_latency(context, wsi, "send lws_issue_raw", n,
 374                             n == p - sb);
 375                 switch (n) {
 376                 case LWS_SSL_CAPABLE_ERROR:
 377                         lwsl_debug("ERROR writing to client socket\n");
 378                         lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS);
 379                         return 0;
 380                 case LWS_SSL_CAPABLE_MORE_SERVICE:
 381                         lws_callback_on_writable(wsi);
 382                         break;
 383                 }
 384
 385                 wsi->u.hdr.parser_state = WSI_TOKEN_NAME_PART;
 386                 wsi->u.hdr.lextable_pos = 0;
 387                 wsi->mode = LWSCM_WSCL_WAITING_SERVER_REPLY;
 388                 lws_set_timeout(wsi, PENDING_TIMEOUT_AWAITING_SERVER_RESPONSE,
 389                                 context->timeout_secs);
 390                 break;
 391
 392         case LWSCM_WSCL_WAITING_SERVER_REPLY:
 393
 394                 /* handle server hung up on us */
 395
 396                 if (pollfd->revents & LWS_POLLHUP) {
 397
 398                         lwsl_debug("Server connection %p (fd=%d) dead\n",
 399                                 (void *)wsi, pollfd->fd);
 400
 401                         goto bail3;
 402                 }
 403
 404                 if (!(pollfd->revents & LWS_POLLIN))
 405                         break;
 406
 407                 /* interpret the server response */
 408
 409                 /*
 410                  *  HTTP/1.1 101 Switching Protocols
 411                  *  Upgrade: websocket
 412                  *  Connection: Upgrade
 413                  *  Sec-WebSocket-Accept: me89jWimTRKTWwrS3aRrL53YZSo=
 414                  *  Sec-WebSocket-Nonce: AQIDBAUGBwgJCgsMDQ4PEC==
 415                  *  Sec-WebSocket-Protocol: chat
 416                  */
 417
 418                 /*
 419                  * we have to take some care here to only take from the
 420                  * socket bytewise.  The browser may (and has been seen to
 421                  * in the case that onopen() performs websocket traffic)
 422                  * coalesce both handshake response and websocket traffic
 423                  * in one packet, since at that point the connection is
 424                  * definitively ready from browser pov.
 425                  */
 426                 len = 1;
 427                 while (wsi->u.hdr.parser_state != WSI_PARSING_COMPLETE &&
 428                        len > 0) {
 429                         n = lws_ssl_capable_read(wsi, &c, 1);
 430                         lws_latency(context, wsi, "send lws_issue_raw", n,
 431                                     n == 1);
 432                         switch (n) {
 433                         case 0:
 434                         case LWS_SSL_CAPABLE_ERROR:
 435                                 goto bail3;
 436                         case LWS_SSL_CAPABLE_MORE_SERVICE:
 437                                 return 0;
 438                         }
 439
 440                         if (lws_parse(wsi, c)) {
 441                                 lwsl_warn("problems parsing header\n");
 442                                 goto bail3;
 443                         }
 444                 }
 445
 446                 /*
 447                  * hs may also be coming in multiple packets, there is a 5-sec
 448                  * libwebsocket timeout still active here too, so if parsing did
 449                  * not complete just wait for next packet coming in this state
 450                  */
 451
 452                 if (wsi->u.hdr.parser_state != WSI_PARSING_COMPLETE)
 453                         break;
 454
 455                 /*
 456                  * otherwise deal with the handshake.  If there's any
 457                  * packet traffic already arrived we'll trigger poll() again
 458                  * right away and deal with it that way
 459                  */
 460
 461                 return lws_client_interpret_server_handshake(wsi);
 462
 463 bail3:
 464                 lwsl_info("closing conn at LWS_CONNMODE...SERVER_REPLY\n");
 465                 lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS);
 466                 return -1;
 467
 468         case LWSCM_WSCL_WAITING_EXTENSION_CONNECT:
 469                 lwsl_ext("LWSCM_WSCL_WAITING_EXTENSION_CONNECT\n");
 470                 break;
 471
 472         case LWSCM_WSCL_PENDING_CANDIDATE_CHILD:
 473                 lwsl_ext("LWSCM_WSCL_PENDING_CANDIDATE_CHILD\n");
 474                 break;
 475         default:
 476                 break;
 477         }
 478
 479         return 0;
 480 }
 481
 482 /*
 483  * In-place str to lower case
 484  */
 485
 486 static void
 487 strtolower(char *s)
 488 {
 489         while (*s) {
 490                 *s = tolower((int)*s);
 491                 s++;
 492         }
 493 }
 494
 495 /**
 496  * lws_http_transaction_completed() - wait for new http transaction or close
 497  * @wsi:        websocket connection
 498  *
 499  *      Returns 1 if the HTTP connection must close now
 500  *      Returns 0 and resets connection to wait for new HTTP header /
 501  *        transaction if possible
 502  */
 503
 504 LWS_VISIBLE int LWS_WARN_UNUSED_RESULT
 505 lws_http_transaction_completed_client(struct lws *wsi)
 506 {
 507         lwsl_debug("%s: wsi %p\n", __func__, wsi);
 508         /* if we can't go back to accept new headers, drop the connection */
 509         if (wsi->u.http.connection_type != HTTP_CONNECTION_KEEP_ALIVE) {
 510                 lwsl_info("%s: %p: close connection\n", __func__, wsi);
 511                 return 1;
 512         }
 513
 514         /* otherwise set ourselves up ready to go again */
 515         wsi->state = LWSS_CLIENT_HTTP_ESTABLISHED;
 516         wsi->mode = LWSCM_HTTP_CLIENT_ACCEPTED;
 517         wsi->u.http.content_length = 0;
 518         wsi->hdr_parsing_completed = 0;
 519
 520         /* He asked for it to stay alive indefinitely */
 521         lws_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
 522
 523         /*
 524          * As client, nothing new is going to come until we ask for it
 525          * we can drop the ah, if any
 526          */
 527         if (wsi->u.hdr.ah) {
 528                 wsi->u.hdr.ah->rxpos = wsi->u.hdr.ah->rxlen;
 529                 lws_header_table_detach(wsi, 0);
 530         }
 531
 532         /* If we're (re)starting on headers, need other implied init */
 533         wsi->u.hdr.ues = URIES_IDLE;
 534
 535         lwsl_info("%s: %p: keep-alive await new transaction\n", __func__, wsi);
 536
 537         return 0;
 538 }
 539
 540 int
 541 lws_client_interpret_server_handshake(struct lws *wsi)
 542 {
 543         int n, len, okay = 0, isErrorCodeReceived = 0, port = 0, ssl = 0;
 544         struct lws_context *context = wsi->context;
 545         int close_reason = LWS_CLOSE_STATUS_PROTOCOL_ERR;
 546         const char *pc, *prot, *ads = NULL, *path;
 547         struct allocated_headers *ah;
 548         char *p;
 549 #ifndef LWS_NO_EXTENSIONS
 550         struct lws_context_per_thread *pt = &context->pt[(int)wsi->tsi];
 551         char *sb = (char *)&pt->serv_buf[0];
 552         const struct lws_ext_options *opts;
 553         const struct lws_extension *ext;
 554         char ext_name[128];
 555         const char *c, *a;
 556         char ignore;
 557         int more = 1;
 558         void *v;
 559 #endif
 560
 561         if (!wsi->do_ws) {
 562                 /* we are being an http client...
 563                  */
 564                 ah = wsi->u.hdr.ah;
 565                 lws_union_transition(wsi, LWSCM_HTTP_CLIENT_ACCEPTED);
 566                 wsi->state = LWSS_CLIENT_HTTP_ESTABLISHED;
 567                 wsi->u.http.ah = ah;
 568         }
 569
 570         /*
 571          * well, what the server sent looked reasonable for syntax.
 572          * Now let's confirm it sent all the necessary headers
 573          *
 574          * http (non-ws) client will expect something like this
 575          *
 576          * HTTP/1.0.200
 577          * server:.libwebsockets
 578          * content-type:.text/html
 579          * content-length:.17703
 580          * set-cookie:.test=LWS_1456736240_336776_COOKIE;Max-Age=360000
 581          *
 582          *
 583          *
 584          */
 585
 586         wsi->u.http.connection_type = HTTP_CONNECTION_KEEP_ALIVE;
 587         p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_HTTP);
 588         if (wsi->do_ws && !p) {
 589                 lwsl_info("no URI\n");
 590                 goto bail3;
 591         }
 592         if (!p) {
 593                 p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_HTTP1_0);
 594                 wsi->u.http.connection_type = HTTP_CONNECTION_CLOSE;
 595         }
 596         if (!p) {
 597                 lwsl_info("no URI\n");
 598                 goto bail3;
 599         }
 600         n = atoi(p);
 601         if (n == 301 || n == 302 || n == 303 || n == 307 || n == 308) {
 602                 p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_HTTP_LOCATION);
 603                 if (!p)
 604                         goto bail3;
 605
 606                 if (lws_parse_uri(p, &prot, &ads, &port, &path))
 607                         goto bail3;
 608
 609                 if (!strcmp(prot, "wss://") || !strcmp(prot, "https://"))
 610                         ssl = 1;
 611
 612                 if (lws_client_reset(wsi, ssl, ads, port, path, ads)) {
 613                         lwsl_err("Redirect failed\n");
 614                         goto bail3;
 615                 }
 616                 return 0;
 617         }
 618
 619         if (!wsi->do_ws) {
 620                 if (n != 200) {
 621                         lwsl_notice("Connection failed with code %d", n);
 622                         goto bail2;
 623                 }
 624
 625                 /* allocate the per-connection user memory (if any) */
 626                 if (lws_ensure_user_space(wsi)) {
 627                         lwsl_err("Problem allocating wsi user mem\n");
 628                         goto bail2;
 629                 }
 630
 631                 if (lws_hdr_total_length(wsi, WSI_TOKEN_HTTP_CONTENT_LENGTH)) {
 632                         wsi->u.http.content_length =
 633                                         atoi(lws_hdr_simple_ptr(wsi,
 634                                                 WSI_TOKEN_HTTP_CONTENT_LENGTH));
 635                         lwsl_notice("%s: incoming content length %d\n", __func__,
 636                                         wsi->u.http.content_length);
 637                         wsi->u.http.content_remain = wsi->u.http.content_length;
 638                 } else /* can't do 1.1 without a content length */
 639                         wsi->u.http.connection_type = HTTP_CONNECTION_CLOSE;
 640
 641                 /*
 642                  * we seem to be good to go, give client last chance to check
 643                  * headers and OK it
 644                  */
 645                 if (wsi->protocol->callback(wsi, LWS_CALLBACK_CLIENT_FILTER_PRE_ESTABLISH,
 646                                             wsi->user_space, NULL, 0))
 647                         goto bail2;
 648
 649                 /* clear his proxy connection timeout */
 650                 lws_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
 651
 652                 wsi->rxflow_change_to = LWS_RXFLOW_ALLOW;
 653
 654                 /* call him back to inform him he is up */
 655                 if (wsi->protocol->callback(wsi,
 656                                 LWS_CALLBACK_ESTABLISHED_CLIENT_HTTP,
 657                                             wsi->user_space, NULL, 0))
 658                         goto bail3;
 659
 660                 /* free up his parsing allocations */
 661                 lws_header_table_detach(wsi, 0);
 662
 663                 lwsl_notice("%s: client connection up\n", __func__);
 664
 665                 return 0;
 666         }
 667
 668         if (lws_hdr_total_length(wsi, WSI_TOKEN_ACCEPT) == 0) {
 669                 lwsl_info("no ACCEPT\n");
 670                 isErrorCodeReceived = 1;
 671                 goto bail3;
 672         }
 673
 674         if (p && strncmp(p, "101", 3)) {
 675                 lwsl_warn(
 676                        "lws_client_handshake: got bad HTTP response '%s'\n", p);
 677                 goto bail3;
 678         }
 679
 680         p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_UPGRADE);
 681         if (!p) {
 682                 lwsl_info("no UPGRADE\n");
 683                 goto bail3;
 684         }
 685         strtolower(p);
 686         if (strcmp(p, "websocket")) {
 687                 lwsl_warn(
 688                       "lws_client_handshake: got bad Upgrade header '%s'\n", p);
 689                 goto bail3;
 690         }
 691
 692         p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_CONNECTION);
 693         if (!p) {
 694                 lwsl_info("no Connection hdr\n");
 695                 goto bail3;
 696         }
 697         strtolower(p);
 698         if (strcmp(p, "upgrade")) {
 699                 lwsl_warn("lws_client_int_s_hs: bad header %s\n", p);
 700                 goto bail3;
 701         }
 702
 703         pc = lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_SENT_PROTOCOLS);
 704         if (!pc) {
 705                 lwsl_parser("lws_client_int_s_hs: no protocol list\n");
 706         } else
 707                 lwsl_parser("lws_client_int_s_hs: protocol list '%s'\n", pc);
 708
 709         /*
 710          * confirm the protocol the server wants to talk was in the list
 711          * of protocols we offered
 712          */
 713
 714         len = lws_hdr_total_length(wsi, WSI_TOKEN_PROTOCOL);
 715         if (!len) {
 716                 lwsl_info("lws_client_int_s_hs: WSI_TOKEN_PROTOCOL is null\n");
 717                 /*
 718                  * no protocol name to work from,
 719                  * default to first protocol
 720                  */
 721                 wsi->protocol = &context->protocols[0];
 722                 goto check_extensions;
 723         }
 724
 725         p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_PROTOCOL);
 726         len = strlen(p);
 727
 728         while (pc && *pc && !okay) {
 729                 if (!strncmp(pc, p, len) &&
 730                     (pc[len] == ',' || pc[len] == '\0')) {
 731                         okay = 1;
 732                         continue;
 733                 }
 734                 while (*pc && *pc++ != ',')
 735                         ;
 736                 while (*pc && *pc == ' ')
 737                         pc++;
 738         }
 739
 740         if (!okay) {
 741                 lwsl_err("lws_client_int_s_hs: got bad protocol %s\n", p);
 742                 goto bail2;
 743         }
 744
 745         /*
 746          * identify the selected protocol struct and set it
 747          */
 748         n = 0;
 749         wsi->protocol = NULL;
 750         while (context->protocols[n].callback && !wsi->protocol) {
 751                 if (strcmp(p, context->protocols[n].name) == 0) {
 752                         wsi->protocol = &context->protocols[n];
 753                         break;
 754                 }
 755                 n++;
 756         }
 757
 758         if (wsi->protocol == NULL) {
 759                 lwsl_err("lws_client_int_s_hs: fail protocol %s\n", p);
 760                 goto bail2;
 761         }
 762
 763
 764 check_extensions:
 765 #ifndef LWS_NO_EXTENSIONS
 766         /* instantiate the accepted extensions */
 767
 768         if (!lws_hdr_total_length(wsi, WSI_TOKEN_EXTENSIONS)) {
 769                 lwsl_ext("no client extensions allowed by server\n");
 770                 goto check_accept;
 771         }
 772
 773         /*
 774          * break down the list of server accepted extensions
 775          * and go through matching them or identifying bogons
 776          */
 777
 778         if (lws_hdr_copy(wsi, sb, LWS_MAX_SOCKET_IO_BUF, WSI_TOKEN_EXTENSIONS) < 0) {
 779                 lwsl_warn("ext list from server failed to copy\n");
 780                 goto bail2;
 781         }
 782
 783         c = sb;
 784         n = 0;
 785         ignore = 0;
 786         a = NULL;
 787         while (more) {
 788
 789                 if (*c && (*c != ',' && *c != '\t')) {
 790                         if (*c == ';') {
 791                                 ignore = 1;
 792                                 if (!a)
 793                                         a = c + 1;
 794                         }
 795                         if (ignore || *c == ' ') {
 796                                 c++;
 797                                 continue;
 798                         }
 799
 800                         ext_name[n] = *c++;
 801                         if (n < sizeof(ext_name) - 1)
 802                                 n++;
 803                         continue;
 804                 }
 805                 ext_name[n] = '\0';
 806                 ignore = 0;
 807                 if (!*c)
 808                         more = 0;
 809                 else {
 810                         c++;
 811                         if (!n)
 812                                 continue;
 813                 }
 814
 815                 /* check we actually support it */
 816
 817                 lwsl_notice("checking client ext %s\n", ext_name);
 818
 819                 n = 0;
 820                 ext = lws_get_context(wsi)->extensions;
 821                 while (ext && ext->callback) {
 822                         if (strcmp(ext_name, ext->name)) {
 823                                 ext++;
 824                                 continue;
 825                         }
 826
 827                         n = 1;
 828                         lwsl_notice("instantiating client ext %s\n", ext_name);
 829
 830                         /* instantiate the extension on this conn */
 831
 832                         wsi->active_extensions[wsi->count_act_ext] = ext;
 833
 834                         /* allow him to construct his ext instance */
 835
 836                         ext->callback(lws_get_context(wsi), ext, wsi,
 837                                       LWS_EXT_CB_CLIENT_CONSTRUCT,
 838                                       (void *)&wsi->act_ext_user[wsi->count_act_ext],
 839                                       (void *)&opts, 0);
 840
 841                         /*
 842                          * allow the user code to override ext defaults if it
 843                          * wants to
 844                          */
 845                         ext_name[0] = '\0';
 846                         if (user_callback_handle_rxflow(wsi->protocol->callback,
 847                                         wsi, LWS_CALLBACK_WS_EXT_DEFAULTS,
 848                                         (char *)ext->name, ext_name,
 849                                         sizeof(ext_name)))
 850                                 goto bail2;
 851
 852                         if (ext_name[0] &&
 853                             lws_ext_parse_options(ext, wsi, wsi->act_ext_user[
 854                                                   wsi->count_act_ext], opts, ext_name,
 855                                                   strlen(ext_name))) {
 856                                 lwsl_err("%s: unable to parse user defaults '%s'",
 857                                          __func__, ext_name);
 858                                 goto bail2;
 859                         }
 860
 861                         /*
 862                          * give the extension the server options
 863                          */
 864                         if (a && lws_ext_parse_options(ext, wsi,
 865                                         wsi->act_ext_user[wsi->count_act_ext],
 866                                         opts, a, c - a)) {
 867                                 lwsl_err("%s: unable to parse remote def '%s'",
 868                                          __func__, a);
 869                                 goto bail2;
 870                         }
 871
 872                         if (ext->callback(lws_get_context(wsi), ext, wsi,
 873                                         LWS_EXT_CB_OPTION_CONFIRM,
 874                                       wsi->act_ext_user[wsi->count_act_ext],
 875                                       NULL, 0)) {
 876                                 lwsl_err("%s: ext %s rejects server options %s",
 877                                          ext->name, a);
 878                                 goto bail2;
 879                         }
 880
 881                         wsi->count_act_ext++;
 882
 883                         ext++;
 884                 }
 885
 886                 if (n == 0) {
 887                         lwsl_warn("Unknown ext '%s'!\n", ext_name);
 888                         goto bail2;
 889                 }
 890
 891                 a = NULL;
 892                 n = 0;
 893         }
 894
 895 check_accept:
 896 #endif
 897
 898         /*
 899          * Confirm his accept token is the one we precomputed
 900          */
 901
 902         p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_ACCEPT);
 903         if (strcmp(p, wsi->u.hdr.ah->initial_handshake_hash_base64)) {
 904                 lwsl_warn("lws_client_int_s_hs: accept '%s' wrong vs '%s'\n", p,
 905                                   wsi->u.hdr.ah->initial_handshake_hash_base64);
 906                 goto bail2;
 907         }
 908
 909         /* allocate the per-connection user memory (if any) */
 910         if (lws_ensure_user_space(wsi)) {
 911                 lwsl_err("Problem allocating wsi user mem\n");
 912                 goto bail2;
 913         }
 914
 915         /*
 916          * we seem to be good to go, give client last chance to check
 917          * headers and OK it
 918          */
 919         if (wsi->protocol->callback(wsi, LWS_CALLBACK_CLIENT_FILTER_PRE_ESTABLISH,
 920                                     wsi->user_space, NULL, 0))
 921                 goto bail2;
 922
 923         /* clear his proxy connection timeout */
 924         lws_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
 925
 926         /* free up his parsing allocations */
 927         lws_header_table_detach(wsi, 0);
 928
 929         lws_union_transition(wsi, LWSCM_WS_CLIENT);
 930         wsi->state = LWSS_ESTABLISHED;
 931
 932         wsi->rxflow_change_to = LWS_RXFLOW_ALLOW;
 933
 934         /*
 935          * create the frame buffer for this connection according to the
 936          * size mentioned in the protocol definition.  If 0 there, then
 937          * use a big default for compatibility
 938          */
 939         n = wsi->protocol->rx_buffer_size;
 940         if (!n)
 941                 n = LWS_MAX_SOCKET_IO_BUF;
 942         n += LWS_PRE;
 943         wsi->u.ws.rx_ubuf = lws_malloc(n + 4 /* 0x0000ffff zlib */);
 944         if (!wsi->u.ws.rx_ubuf) {
 945                 lwsl_err("Out of Mem allocating rx buffer %d\n", n);
 946                 goto bail2;
 947         }
 948        wsi->u.ws.rx_ubuf_alloc = n;
 949         lwsl_info("Allocating client RX buffer %d\n", n);
 950
 951         if (setsockopt(wsi->sock, SOL_SOCKET, SO_SNDBUF, (const char *)&n,
 952                        sizeof n)) {
 953                 lwsl_warn("Failed to set SNDBUF to %d", n);
 954                 goto bail3;
 955         }
 956
 957         lwsl_debug("handshake OK for protocol %s\n", wsi->protocol->name);
 958
 959         /* call him back to inform him he is up */
 960
 961         if (wsi->protocol->callback(wsi, LWS_CALLBACK_CLIENT_ESTABLISHED,
 962                                     wsi->user_space, NULL, 0))
 963                 goto bail3;
 964 #ifndef LWS_NO_EXTENSIONS
 965         /*
 966          * inform all extensions, not just active ones since they
 967          * already know
 968          */
 969         ext = context->extensions;
 970
 971         while (ext && ext->callback) {
 972                 v = NULL;
 973                 for (n = 0; n < wsi->count_act_ext; n++)
 974                         if (wsi->active_extensions[n] == ext)
 975                                 v = wsi->act_ext_user[n];
 976
 977                 ext->callback(context, ext, wsi,
 978                           LWS_EXT_CB_ANY_WSI_ESTABLISHED, v, NULL, 0);
 979                 ext++;
 980         }
 981 #endif
 982
 983         return 0;
 984
 985 bail3:
 986         close_reason = LWS_CLOSE_STATUS_NOSTATUS;
 987
 988 bail2:
 989         if (wsi->protocol && wsi->state == LWSS_ESTABLISHED) {
 990                 if (isErrorCodeReceived && p) {
 991                         wsi->protocol->callback(wsi,
 992                                 LWS_CALLBACK_CLIENT_CONNECTION_ERROR,
 993                                                 wsi->user_space, p,
 994                                                 (unsigned int)strlen(p));
 995                 } else {
 996                         wsi->protocol->callback(wsi,
 997                                 LWS_CALLBACK_CLIENT_CONNECTION_ERROR,
 998                                                 wsi->user_space, NULL, 0);
 999                 }
1000         }
1001
1002         lwsl_info("closing connection due to bail2 connection error\n");
1003
1004         /* closing will free up his parsing allocations */
1005         lws_close_free_wsi(wsi, close_reason);
1006
1007         return 1;
1008 }
1009
1010
1011 char *
1012 lws_generate_client_handshake(struct lws *wsi, char *pkt)
1013 {
1014         char buf[128], hash[20], key_b64[40], *p = pkt;
1015         struct lws_context *context = wsi->context;
1016         const char *meth;
1017         int n;
1018 #ifndef LWS_NO_EXTENSIONS
1019         const struct lws_extension *ext;
1020         int ext_count = 0;
1021 #endif
1022
1023         meth = lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_METHOD);
1024         if (!meth) {
1025                 meth = "GET";
1026                 wsi->do_ws = 1;
1027         } else
1028                 wsi->do_ws = 0;
1029
1030         if (wsi->do_ws) {
1031                 /*
1032                  * create the random key
1033                  */
1034                 n = lws_get_random(context, hash, 16);
1035                 if (n != 16) {
1036                         lwsl_err("Unable to read from random dev %s\n",
1037                                  SYSTEM_RANDOM_FILEPATH);
1038                         lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS);
1039                         return NULL;
1040                 }
1041
1042                 lws_b64_encode_string(hash, 16, key_b64, sizeof(key_b64));
1043         }
1044
1045         /*
1046          * 04 example client handshake
1047          *
1048          * GET /chat HTTP/1.1
1049          * Host: server.example.com
1050          * Upgrade: websocket
1051          * Connection: Upgrade
1052          * Sec-WebSocket-Key: dGhlIHNhbXBsZSBub25jZQ==
1053          * Sec-WebSocket-Origin: http://example.com
1054          * Sec-WebSocket-Protocol: chat, superchat
1055          * Sec-WebSocket-Version: 4
1056          */
1057
1058         p += sprintf(p, "%s %s HTTP/1.1\x0d\x0a", meth,
1059                      lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_URI));
1060
1061         p += sprintf(p, "Pragma: no-cache\x0d\x0a"
1062                         "Cache-Control: no-cache\x0d\x0a");
1063
1064         p += sprintf(p, "Host: %s\x0d\x0a",
1065                      lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_HOST));
1066
1067         if (lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_ORIGIN))
1068                 p += sprintf(p, "Origin: http://%s\x0d\x0a",
1069                              lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_ORIGIN));
1070
1071         if (wsi->do_ws) {
1072                 p += sprintf(p, "Upgrade: websocket\x0d\x0a"
1073                                 "Connection: Upgrade\x0d\x0a"
1074                                 "Sec-WebSocket-Key: ");
1075                 strcpy(p, key_b64);
1076                 p += strlen(key_b64);
1077                 p += sprintf(p, "\x0d\x0a");
1078                 if (lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_SENT_PROTOCOLS))
1079                         p += sprintf(p, "Sec-WebSocket-Protocol: %s\x0d\x0a",
1080                              lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_SENT_PROTOCOLS));
1081
1082                 /* tell the server what extensions we could support */
1083
1084                 p += sprintf(p, "Sec-WebSocket-Extensions: ");
1085 #ifndef LWS_NO_EXTENSIONS
1086                 ext = context->extensions;
1087                 while (ext && ext->callback) {
1088                         n = lws_ext_cb_all_exts(context, wsi,
1089                                    LWS_EXT_CB_CHECK_OK_TO_PROPOSE_EXTENSION,
1090                                    (char *)ext->name, 0);
1091                         if (n) { /* an extension vetos us */
1092                                 lwsl_ext("ext %s vetoed\n", (char *)ext->name);
1093                                 ext++;
1094                                 continue;
1095                         }
1096                         n = context->protocols[0].callback(wsi,
1097                                 LWS_CALLBACK_CLIENT_CONFIRM_EXTENSION_SUPPORTED,
1098                                         wsi->user_space, (char *)ext->name, 0);
1099
1100                         /*
1101                          * zero return from callback means
1102                          * go ahead and allow the extension,
1103                          * it's what we get if the callback is
1104                          * unhandled
1105                          */
1106
1107                         if (n) {
1108                                 ext++;
1109                                 continue;
1110                         }
1111
1112                         /* apply it */
1113
1114                         if (ext_count)
1115                                 *p++ = ',';
1116                         p += sprintf(p, "%s", ext->client_offer);
1117                         ext_count++;
1118
1119                         ext++;
1120                 }
1121 #endif
1122                 p += sprintf(p, "\x0d\x0a");
1123
1124                 if (wsi->ietf_spec_revision)
1125                         p += sprintf(p, "Sec-WebSocket-Version: %d\x0d\x0a",
1126                                      wsi->ietf_spec_revision);
1127
1128                 /* prepare the expected server accept response */
1129
1130                 key_b64[39] = '\0'; /* enforce composed length below buf sizeof */
1131                 n = sprintf(buf, "%s258EAFA5-E914-47DA-95CA-C5AB0DC85B11", key_b64);
1132
1133                 lws_SHA1((unsigned char *)buf, n, (unsigned char *)hash);
1134
1135                 lws_b64_encode_string(hash, 20,
1136                                       wsi->u.hdr.ah->initial_handshake_hash_base64,
1137                                       sizeof(wsi->u.hdr.ah->initial_handshake_hash_base64));
1138         }
1139
1140         /* give userland a chance to append, eg, cookies */
1141
1142         context->protocols[0].callback(wsi, LWS_CALLBACK_CLIENT_APPEND_HANDSHAKE_HEADER,
1143                                        NULL, &p, (pkt + LWS_MAX_SOCKET_IO_BUF) - p - 12);
1144
1145         p += sprintf(p, "\x0d\x0a");
1146
1147         return p;
1148 }
1149