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 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 #ifdef LWS_WITH_HTTP_PROXY
 626         wsi->perform_rewrite = 0;
 627         if (lws_hdr_total_length(wsi, WSI_TOKEN_HTTP_CONTENT_TYPE)) {
 628                 if (!strncmp(lws_hdr_simple_ptr(wsi, WSI_TOKEN_HTTP_CONTENT_TYPE),
 629                                 "text/html", 9))
 630                         wsi->perform_rewrite = 1;
 631         }
 632 #endif
 633
 634                 /* allocate the per-connection user memory (if any) */
 635                 if (lws_ensure_user_space(wsi)) {
 636                         lwsl_err("Problem allocating wsi user mem\n");
 637                         goto bail2;
 638                 }
 639
 640                 /* he may choose to send us stuff in chunked transfer-coding */
 641                 wsi->chunked = 0;
 642                 wsi->chunk_remaining = 0; /* ie, next thing is chunk size */
 643                 if (lws_hdr_total_length(wsi, WSI_TOKEN_HTTP_TRANSFER_ENCODING)) {
 644                         wsi->chunked = !strcmp(lws_hdr_simple_ptr(wsi,
 645                                                WSI_TOKEN_HTTP_TRANSFER_ENCODING),
 646                                         "chunked");
 647                         /* first thing is hex, after payload there is crlf */
 648                         wsi->chunk_parser = ELCP_HEX;
 649                 }
 650
 651                 if (lws_hdr_total_length(wsi, WSI_TOKEN_HTTP_CONTENT_LENGTH)) {
 652                         wsi->u.http.content_length =
 653                                         atoi(lws_hdr_simple_ptr(wsi,
 654                                                 WSI_TOKEN_HTTP_CONTENT_LENGTH));
 655                         lwsl_notice("%s: incoming content length %d\n", __func__,
 656                                         wsi->u.http.content_length);
 657                         wsi->u.http.content_remain = wsi->u.http.content_length;
 658                 } else /* can't do 1.1 without a content length or chunked */
 659                         if (!wsi->chunked)
 660                                 wsi->u.http.connection_type = HTTP_CONNECTION_CLOSE;
 661
 662                 /*
 663                  * we seem to be good to go, give client last chance to check
 664                  * headers and OK it
 665                  */
 666                 if (wsi->protocol->callback(wsi, LWS_CALLBACK_CLIENT_FILTER_PRE_ESTABLISH,
 667                                             wsi->user_space, NULL, 0))
 668                         goto bail2;
 669
 670                 /* clear his proxy connection timeout */
 671                 lws_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
 672
 673                 wsi->rxflow_change_to = LWS_RXFLOW_ALLOW;
 674
 675                 /* call him back to inform him he is up */
 676                 if (wsi->protocol->callback(wsi,
 677                                 LWS_CALLBACK_ESTABLISHED_CLIENT_HTTP,
 678                                             wsi->user_space, NULL, 0))
 679                         goto bail3;
 680
 681                 /* free up his parsing allocations */
 682                 lws_header_table_detach(wsi, 0);
 683
 684                 lwsl_notice("%s: client connection up\n", __func__);
 685
 686                 return 0;
 687         }
 688
 689         if (lws_hdr_total_length(wsi, WSI_TOKEN_ACCEPT) == 0) {
 690                 lwsl_info("no ACCEPT\n");
 691                 isErrorCodeReceived = 1;
 692                 goto bail3;
 693         }
 694
 695         if (p && strncmp(p, "101", 3)) {
 696                 lwsl_warn(
 697                        "lws_client_handshake: got bad HTTP response '%s'\n", p);
 698                 goto bail3;
 699         }
 700
 701         p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_UPGRADE);
 702         if (!p) {
 703                 lwsl_info("no UPGRADE\n");
 704                 goto bail3;
 705         }
 706         strtolower(p);
 707         if (strcmp(p, "websocket")) {
 708                 lwsl_warn(
 709                       "lws_client_handshake: got bad Upgrade header '%s'\n", p);
 710                 goto bail3;
 711         }
 712
 713         p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_CONNECTION);
 714         if (!p) {
 715                 lwsl_info("no Connection hdr\n");
 716                 goto bail3;
 717         }
 718         strtolower(p);
 719         if (strcmp(p, "upgrade")) {
 720                 lwsl_warn("lws_client_int_s_hs: bad header %s\n", p);
 721                 goto bail3;
 722         }
 723
 724         pc = lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_SENT_PROTOCOLS);
 725         if (!pc) {
 726                 lwsl_parser("lws_client_int_s_hs: no protocol list\n");
 727         } else
 728                 lwsl_parser("lws_client_int_s_hs: protocol list '%s'\n", pc);
 729
 730         /*
 731          * confirm the protocol the server wants to talk was in the list
 732          * of protocols we offered
 733          */
 734
 735         len = lws_hdr_total_length(wsi, WSI_TOKEN_PROTOCOL);
 736         if (!len) {
 737                 lwsl_info("lws_client_int_s_hs: WSI_TOKEN_PROTOCOL is null\n");
 738                 /*
 739                  * no protocol name to work from,
 740                  * default to first protocol
 741                  */
 742                 wsi->protocol = &context->protocols[0];
 743                 goto check_extensions;
 744         }
 745
 746         p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_PROTOCOL);
 747         len = strlen(p);
 748
 749         while (pc && *pc && !okay) {
 750                 if (!strncmp(pc, p, len) &&
 751                     (pc[len] == ',' || pc[len] == '\0')) {
 752                         okay = 1;
 753                         continue;
 754                 }
 755                 while (*pc && *pc++ != ',')
 756                         ;
 757                 while (*pc && *pc == ' ')
 758                         pc++;
 759         }
 760
 761         if (!okay) {
 762                 lwsl_err("lws_client_int_s_hs: got bad protocol %s\n", p);
 763                 goto bail2;
 764         }
 765
 766         /*
 767          * identify the selected protocol struct and set it
 768          */
 769         n = 0;
 770         wsi->protocol = NULL;
 771         while (context->protocols[n].callback && !wsi->protocol) {
 772                 if (strcmp(p, context->protocols[n].name) == 0) {
 773                         wsi->protocol = &context->protocols[n];
 774                         break;
 775                 }
 776                 n++;
 777         }
 778
 779         if (wsi->protocol == NULL) {
 780                 lwsl_err("lws_client_int_s_hs: fail protocol %s\n", p);
 781                 goto bail2;
 782         }
 783
 784
 785 check_extensions:
 786 #ifndef LWS_NO_EXTENSIONS
 787         /* instantiate the accepted extensions */
 788
 789         if (!lws_hdr_total_length(wsi, WSI_TOKEN_EXTENSIONS)) {
 790                 lwsl_ext("no client extensions allowed by server\n");
 791                 goto check_accept;
 792         }
 793
 794         /*
 795          * break down the list of server accepted extensions
 796          * and go through matching them or identifying bogons
 797          */
 798
 799         if (lws_hdr_copy(wsi, sb, LWS_MAX_SOCKET_IO_BUF, WSI_TOKEN_EXTENSIONS) < 0) {
 800                 lwsl_warn("ext list from server failed to copy\n");
 801                 goto bail2;
 802         }
 803
 804         c = sb;
 805         n = 0;
 806         ignore = 0;
 807         a = NULL;
 808         while (more) {
 809
 810                 if (*c && (*c != ',' && *c != '\t')) {
 811                         if (*c == ';') {
 812                                 ignore = 1;
 813                                 if (!a)
 814                                         a = c + 1;
 815                         }
 816                         if (ignore || *c == ' ') {
 817                                 c++;
 818                                 continue;
 819                         }
 820
 821                         ext_name[n] = *c++;
 822                         if (n < sizeof(ext_name) - 1)
 823                                 n++;
 824                         continue;
 825                 }
 826                 ext_name[n] = '\0';
 827                 ignore = 0;
 828                 if (!*c)
 829                         more = 0;
 830                 else {
 831                         c++;
 832                         if (!n)
 833                                 continue;
 834                 }
 835
 836                 /* check we actually support it */
 837
 838                 lwsl_notice("checking client ext %s\n", ext_name);
 839
 840                 n = 0;
 841                 ext = lws_get_context(wsi)->extensions;
 842                 while (ext && ext->callback) {
 843                         if (strcmp(ext_name, ext->name)) {
 844                                 ext++;
 845                                 continue;
 846                         }
 847
 848                         n = 1;
 849                         lwsl_notice("instantiating client ext %s\n", ext_name);
 850
 851                         /* instantiate the extension on this conn */
 852
 853                         wsi->active_extensions[wsi->count_act_ext] = ext;
 854
 855                         /* allow him to construct his ext instance */
 856
 857                         ext->callback(lws_get_context(wsi), ext, wsi,
 858                                       LWS_EXT_CB_CLIENT_CONSTRUCT,
 859                                       (void *)&wsi->act_ext_user[wsi->count_act_ext],
 860                                       (void *)&opts, 0);
 861
 862                         /*
 863                          * allow the user code to override ext defaults if it
 864                          * wants to
 865                          */
 866                         ext_name[0] = '\0';
 867                         if (user_callback_handle_rxflow(wsi->protocol->callback,
 868                                         wsi, LWS_CALLBACK_WS_EXT_DEFAULTS,
 869                                         (char *)ext->name, ext_name,
 870                                         sizeof(ext_name)))
 871                                 goto bail2;
 872
 873                         if (ext_name[0] &&
 874                             lws_ext_parse_options(ext, wsi, wsi->act_ext_user[
 875                                                   wsi->count_act_ext], opts, ext_name,
 876                                                   strlen(ext_name))) {
 877                                 lwsl_err("%s: unable to parse user defaults '%s'",
 878                                          __func__, ext_name);
 879                                 goto bail2;
 880                         }
 881
 882                         /*
 883                          * give the extension the server options
 884                          */
 885                         if (a && lws_ext_parse_options(ext, wsi,
 886                                         wsi->act_ext_user[wsi->count_act_ext],
 887                                         opts, a, c - a)) {
 888                                 lwsl_err("%s: unable to parse remote def '%s'",
 889                                          __func__, a);
 890                                 goto bail2;
 891                         }
 892
 893                         if (ext->callback(lws_get_context(wsi), ext, wsi,
 894                                         LWS_EXT_CB_OPTION_CONFIRM,
 895                                       wsi->act_ext_user[wsi->count_act_ext],
 896                                       NULL, 0)) {
 897                                 lwsl_err("%s: ext %s rejects server options %s",
 898                                          ext->name, a);
 899                                 goto bail2;
 900                         }
 901
 902                         wsi->count_act_ext++;
 903
 904                         ext++;
 905                 }
 906
 907                 if (n == 0) {
 908                         lwsl_warn("Unknown ext '%s'!\n", ext_name);
 909                         goto bail2;
 910                 }
 911
 912                 a = NULL;
 913                 n = 0;
 914         }
 915
 916 check_accept:
 917 #endif
 918
 919         /*
 920          * Confirm his accept token is the one we precomputed
 921          */
 922
 923         p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_ACCEPT);
 924         if (strcmp(p, wsi->u.hdr.ah->initial_handshake_hash_base64)) {
 925                 lwsl_warn("lws_client_int_s_hs: accept '%s' wrong vs '%s'\n", p,
 926                                   wsi->u.hdr.ah->initial_handshake_hash_base64);
 927                 goto bail2;
 928         }
 929
 930         /* allocate the per-connection user memory (if any) */
 931         if (lws_ensure_user_space(wsi)) {
 932                 lwsl_err("Problem allocating wsi user mem\n");
 933                 goto bail2;
 934         }
 935
 936         /*
 937          * we seem to be good to go, give client last chance to check
 938          * headers and OK it
 939          */
 940         if (wsi->protocol->callback(wsi, LWS_CALLBACK_CLIENT_FILTER_PRE_ESTABLISH,
 941                                     wsi->user_space, NULL, 0))
 942                 goto bail2;
 943
 944         /* clear his proxy connection timeout */
 945         lws_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
 946
 947         /* free up his parsing allocations */
 948         lws_header_table_detach(wsi, 0);
 949
 950         lws_union_transition(wsi, LWSCM_WS_CLIENT);
 951         wsi->state = LWSS_ESTABLISHED;
 952
 953         wsi->rxflow_change_to = LWS_RXFLOW_ALLOW;
 954
 955         /*
 956          * create the frame buffer for this connection according to the
 957          * size mentioned in the protocol definition.  If 0 there, then
 958          * use a big default for compatibility
 959          */
 960         n = wsi->protocol->rx_buffer_size;
 961         if (!n)
 962                 n = LWS_MAX_SOCKET_IO_BUF;
 963         n += LWS_PRE;
 964         wsi->u.ws.rx_ubuf = lws_malloc(n + 4 /* 0x0000ffff zlib */);
 965         if (!wsi->u.ws.rx_ubuf) {
 966                 lwsl_err("Out of Mem allocating rx buffer %d\n", n);
 967                 goto bail2;
 968         }
 969        wsi->u.ws.rx_ubuf_alloc = n;
 970         lwsl_info("Allocating client RX buffer %d\n", n);
 971
 972         if (setsockopt(wsi->sock, SOL_SOCKET, SO_SNDBUF, (const char *)&n,
 973                        sizeof n)) {
 974                 lwsl_warn("Failed to set SNDBUF to %d", n);
 975                 goto bail3;
 976         }
 977
 978         lwsl_debug("handshake OK for protocol %s\n", wsi->protocol->name);
 979
 980         /* call him back to inform him he is up */
 981
 982         if (wsi->protocol->callback(wsi, LWS_CALLBACK_CLIENT_ESTABLISHED,
 983                                     wsi->user_space, NULL, 0))
 984                 goto bail3;
 985 #ifndef LWS_NO_EXTENSIONS
 986         /*
 987          * inform all extensions, not just active ones since they
 988          * already know
 989          */
 990         ext = context->extensions;
 991
 992         while (ext && ext->callback) {
 993                 v = NULL;
 994                 for (n = 0; n < wsi->count_act_ext; n++)
 995                         if (wsi->active_extensions[n] == ext)
 996                                 v = wsi->act_ext_user[n];
 997
 998                 ext->callback(context, ext, wsi,
 999                           LWS_EXT_CB_ANY_WSI_ESTABLISHED, v, NULL, 0);
1000                 ext++;
1001         }
1002 #endif
1003
1004         return 0;
1005
1006 bail3:
1007         close_reason = LWS_CLOSE_STATUS_NOSTATUS;
1008
1009 bail2:
1010         if (wsi->protocol && wsi->state == LWSS_ESTABLISHED) {
1011                 if (isErrorCodeReceived && p) {
1012                         wsi->protocol->callback(wsi,
1013                                 LWS_CALLBACK_CLIENT_CONNECTION_ERROR,
1014                                                 wsi->user_space, p,
1015                                                 (unsigned int)strlen(p));
1016                 } else {
1017                         wsi->protocol->callback(wsi,
1018                                 LWS_CALLBACK_CLIENT_CONNECTION_ERROR,
1019                                                 wsi->user_space, NULL, 0);
1020                 }
1021         }
1022
1023         lwsl_info("closing connection due to bail2 connection error\n");
1024
1025         /* closing will free up his parsing allocations */
1026         lws_close_free_wsi(wsi, close_reason);
1027
1028         return 1;
1029 }
1030
1031
1032 char *
1033 lws_generate_client_handshake(struct lws *wsi, char *pkt)
1034 {
1035         char buf[128], hash[20], key_b64[40], *p = pkt;
1036         struct lws_context *context = wsi->context;
1037         const char *meth;
1038         int n;
1039 #ifndef LWS_NO_EXTENSIONS
1040         const struct lws_extension *ext;
1041         int ext_count = 0;
1042 #endif
1043
1044         meth = lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_METHOD);
1045         if (!meth) {
1046                 meth = "GET";
1047                 wsi->do_ws = 1;
1048         } else
1049                 wsi->do_ws = 0;
1050
1051         if (wsi->do_ws) {
1052                 /*
1053                  * create the random key
1054                  */
1055                 n = lws_get_random(context, hash, 16);
1056                 if (n != 16) {
1057                         lwsl_err("Unable to read from random dev %s\n",
1058                                  SYSTEM_RANDOM_FILEPATH);
1059                         lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS);
1060                         return NULL;
1061                 }
1062
1063                 lws_b64_encode_string(hash, 16, key_b64, sizeof(key_b64));
1064         }
1065
1066         /*
1067          * 04 example client handshake
1068          *
1069          * GET /chat HTTP/1.1
1070          * Host: server.example.com
1071          * Upgrade: websocket
1072          * Connection: Upgrade
1073          * Sec-WebSocket-Key: dGhlIHNhbXBsZSBub25jZQ==
1074          * Sec-WebSocket-Origin: http://example.com
1075          * Sec-WebSocket-Protocol: chat, superchat
1076          * Sec-WebSocket-Version: 4
1077          */
1078
1079         p += sprintf(p, "%s %s HTTP/1.1\x0d\x0a", meth,
1080                      lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_URI));
1081
1082         p += sprintf(p, "Pragma: no-cache\x0d\x0a"
1083                         "Cache-Control: no-cache\x0d\x0a");
1084
1085         p += sprintf(p, "Host: %s\x0d\x0a",
1086                      lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_HOST));
1087
1088         if (lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_ORIGIN))
1089                 p += sprintf(p, "Origin: http://%s\x0d\x0a",
1090                              lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_ORIGIN));
1091
1092         if (wsi->do_ws) {
1093                 p += sprintf(p, "Upgrade: websocket\x0d\x0a"
1094                                 "Connection: Upgrade\x0d\x0a"
1095                                 "Sec-WebSocket-Key: ");
1096                 strcpy(p, key_b64);
1097                 p += strlen(key_b64);
1098                 p += sprintf(p, "\x0d\x0a");
1099                 if (lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_SENT_PROTOCOLS))
1100                         p += sprintf(p, "Sec-WebSocket-Protocol: %s\x0d\x0a",
1101                              lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_SENT_PROTOCOLS));
1102
1103                 /* tell the server what extensions we could support */
1104
1105 #ifndef LWS_NO_EXTENSIONS
1106                 ext = context->extensions;
1107                 while (ext && ext->callback) {
1108                         n = lws_ext_cb_all_exts(context, wsi,
1109                                    LWS_EXT_CB_CHECK_OK_TO_PROPOSE_EXTENSION,
1110                                    (char *)ext->name, 0);
1111                         if (n) { /* an extension vetos us */
1112                                 lwsl_ext("ext %s vetoed\n", (char *)ext->name);
1113                                 ext++;
1114                                 continue;
1115                         }
1116                         n = context->protocols[0].callback(wsi,
1117                                 LWS_CALLBACK_CLIENT_CONFIRM_EXTENSION_SUPPORTED,
1118                                         wsi->user_space, (char *)ext->name, 0);
1119
1120                         /*
1121                          * zero return from callback means
1122                          * go ahead and allow the extension,
1123                          * it's what we get if the callback is
1124                          * unhandled
1125                          */
1126
1127                         if (n) {
1128                                 ext++;
1129                                 continue;
1130                         }
1131
1132                         /* apply it */
1133
1134                         if (ext_count)
1135                                 *p++ = ',';
1136                         else
1137                                 p += sprintf(p, "Sec-WebSocket-Extensions: ");
1138                         p += sprintf(p, "%s", ext->client_offer);
1139                         ext_count++;
1140
1141                         ext++;
1142                 }
1143                 if (ext_count)
1144                         p += sprintf(p, "\x0d\x0a");
1145 #endif
1146
1147                 if (wsi->ietf_spec_revision)
1148                         p += sprintf(p, "Sec-WebSocket-Version: %d\x0d\x0a",
1149                                      wsi->ietf_spec_revision);
1150
1151                 /* prepare the expected server accept response */
1152
1153                 key_b64[39] = '\0'; /* enforce composed length below buf sizeof */
1154                 n = sprintf(buf, "%s258EAFA5-E914-47DA-95CA-C5AB0DC85B11", key_b64);
1155
1156                 lws_SHA1((unsigned char *)buf, n, (unsigned char *)hash);
1157
1158                 lws_b64_encode_string(hash, 20,
1159                                       wsi->u.hdr.ah->initial_handshake_hash_base64,
1160                                       sizeof(wsi->u.hdr.ah->initial_handshake_hash_base64));
1161         }
1162
1163         /* give userland a chance to append, eg, cookies */
1164
1165         context->protocols[0].callback(wsi, LWS_CALLBACK_CLIENT_APPEND_HANDSHAKE_HEADER,
1166                                        NULL, &p, (pkt + LWS_MAX_SOCKET_IO_BUF) - p - 12);
1167
1168         p += sprintf(p, "\x0d\x0a");
1169
1170         return p;
1171 }
1172