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 %ld\n", __func__, (long)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 %ld\n", __func__, (long)len);
  61                 return 0;
  62         default:
  63                 break;
  64         }
  65
  66         return 0;
  67 }
  68
  69 LWS_VISIBLE LWS_EXTERN void
  70 lws_client_http_body_pending(struct lws *wsi, int something_left_to_send)
  71 {
  72         wsi->client_http_body_pending = !!something_left_to_send;
  73 }
  74
  75 int
  76 lws_client_socket_service(struct lws_context *context, struct lws *wsi,
  77                           struct lws_pollfd *pollfd)
  78 {
  79         struct lws_context_per_thread *pt = &context->pt[(int)wsi->tsi];
  80         char *p = (char *)&pt->serv_buf[0];
  81         const char *cce = NULL;
  82         unsigned char c;
  83         char *sb = p;
  84         int n, len;
  85
  86         switch (wsi->mode) {
  87
  88         case LWSCM_WSCL_WAITING_CONNECT:
  89
  90                 /*
  91                  * we are under PENDING_TIMEOUT_SENT_CLIENT_HANDSHAKE
  92                  * timeout protection set in client-handshake.c
  93                  */
  94
  95                 if (!lws_client_connect_2(wsi)) {
  96                         /* closed */
  97                         lwsl_client("closed\n");
  98                         return -1;
  99                 }
 100
 101                 /* either still pending connection, or changed mode */
 102                 return 0;
 103
 104         case LWSCM_WSCL_WAITING_PROXY_REPLY:
 105
 106                 /* handle proxy hung up on us */
 107
 108                 if (pollfd->revents & LWS_POLLHUP) {
 109
 110                         lwsl_warn("Proxy connection %p (fd=%d) dead\n",
 111                                   (void *)wsi, pollfd->fd);
 112
 113                         lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS);
 114                         return 0;
 115                 }
 116
 117                 n = recv(wsi->sock, sb, context->pt_serv_buf_size, 0);
 118                 if (n < 0) {
 119                         if (LWS_ERRNO == LWS_EAGAIN) {
 120                                 lwsl_debug("Proxy read returned EAGAIN... retrying\n");
 121                                 return 0;
 122                         }
 123
 124                         lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS);
 125                         lwsl_err("ERROR reading from proxy socket\n");
 126                         return 0;
 127                 }
 128
 129                 pt->serv_buf[13] = '\0';
 130                 if (strcmp(sb, "HTTP/1.0 200 ") &&
 131                     strcmp(sb, "HTTP/1.1 200 ")) {
 132                         lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS);
 133                         lwsl_err("ERROR proxy: %s\n", sb);
 134                         return 0;
 135                 }
 136
 137                 /* clear his proxy connection timeout */
 138
 139                 lws_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
 140
 141                 /* fallthru */
 142
 143         case LWSCM_WSCL_ISSUE_HANDSHAKE:
 144
 145                 /*
 146                  * we are under PENDING_TIMEOUT_SENT_CLIENT_HANDSHAKE
 147                  * timeout protection set in client-handshake.c
 148                  *
 149                  * take care of our lws_callback_on_writable
 150                  * happening at a time when there's no real connection yet
 151                  */
 152                 if (lws_change_pollfd(wsi, LWS_POLLOUT, 0))
 153                         return -1;
 154
 155 #ifdef LWS_OPENSSL_SUPPORT
 156                 /* we can retry this... just cook the SSL BIO the first time */
 157
 158                 if (wsi->use_ssl && !wsi->ssl) {
 159                         if (lws_ssl_client_bio_create(wsi))
 160                                 return -1;
 161                 }
 162
 163                 if (wsi->use_ssl) {
 164                         n = lws_ssl_client_connect1(wsi);
 165                         if (!n)
 166                                 return 0;
 167                         if (n < 0) {
 168                                 cce = "lws_ssl_client_connect1 failed";
 169                                 goto bail3;
 170                         }
 171                 } else
 172                         wsi->ssl = NULL;
 173
 174                 /* fallthru */
 175
 176         case LWSCM_WSCL_WAITING_SSL:
 177
 178                 if (wsi->use_ssl) {
 179                         n = lws_ssl_client_connect2(wsi);
 180                         if (!n)
 181                                 return 0;
 182                         if (n < 0) {
 183                                 cce = "lws_ssl_client_connect2 failed";
 184                                 goto bail3;
 185                         }
 186                 } else
 187                         wsi->ssl = NULL;
 188 #endif
 189
 190                 wsi->mode = LWSCM_WSCL_ISSUE_HANDSHAKE2;
 191                 lws_set_timeout(wsi, PENDING_TIMEOUT_AWAITING_CLIENT_HS_SEND,
 192                                 context->timeout_secs);
 193
 194                 /* fallthru */
 195
 196         case LWSCM_WSCL_ISSUE_HANDSHAKE2:
 197                 p = lws_generate_client_handshake(wsi, p);
 198                 if (p == NULL) {
 199                         lwsl_err("Failed to generate handshake for client\n");
 200                         lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS);
 201                         return 0;
 202                 }
 203
 204                 /* send our request to the server */
 205
 206                 lws_latency_pre(context, wsi);
 207
 208                 n = lws_ssl_capable_write(wsi, (unsigned char *)sb, p - sb);
 209                 lws_latency(context, wsi, "send lws_issue_raw", n,
 210                             n == p - sb);
 211                 switch (n) {
 212                 case LWS_SSL_CAPABLE_ERROR:
 213                         lwsl_debug("ERROR writing to client socket\n");
 214                         lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS);
 215                         return 0;
 216                 case LWS_SSL_CAPABLE_MORE_SERVICE:
 217                         lws_callback_on_writable(wsi);
 218                         break;
 219                 }
 220
 221                 if (wsi->client_http_body_pending) {
 222                         wsi->mode = LWSCM_WSCL_ISSUE_HTTP_BODY;
 223                         lws_set_timeout(wsi, PENDING_TIMEOUT_CLIENT_ISSUE_PAYLOAD,
 224                                         context->timeout_secs);
 225                         /* user code must ask for writable callback */
 226                         break;
 227                 }
 228
 229                 goto client_http_body_sent;
 230
 231         case LWSCM_WSCL_ISSUE_HTTP_BODY:
 232                 if (wsi->client_http_body_pending) {
 233                         lws_set_timeout(wsi, PENDING_TIMEOUT_CLIENT_ISSUE_PAYLOAD,
 234                                         context->timeout_secs);
 235                         /* user code must ask for writable callback */
 236                         break;
 237                 }
 238 client_http_body_sent:
 239                 wsi->u.hdr.parser_state = WSI_TOKEN_NAME_PART;
 240                 wsi->u.hdr.lextable_pos = 0;
 241                 wsi->mode = LWSCM_WSCL_WAITING_SERVER_REPLY;
 242                 lws_set_timeout(wsi, PENDING_TIMEOUT_AWAITING_SERVER_RESPONSE,
 243                                 context->timeout_secs);
 244                 break;
 245
 246         case LWSCM_WSCL_WAITING_SERVER_REPLY:
 247
 248                 /* handle server hung up on us */
 249
 250                 if (pollfd->revents & LWS_POLLHUP) {
 251
 252                         lwsl_debug("Server connection %p (fd=%d) dead\n",
 253                                 (void *)wsi, pollfd->fd);
 254                         cce = "Peer hung up";
 255                         goto bail3;
 256                 }
 257
 258                 if (!(pollfd->revents & LWS_POLLIN))
 259                         break;
 260
 261                 /* interpret the server response */
 262
 263                 /*
 264                  *  HTTP/1.1 101 Switching Protocols
 265                  *  Upgrade: websocket
 266                  *  Connection: Upgrade
 267                  *  Sec-WebSocket-Accept: me89jWimTRKTWwrS3aRrL53YZSo=
 268                  *  Sec-WebSocket-Nonce: AQIDBAUGBwgJCgsMDQ4PEC==
 269                  *  Sec-WebSocket-Protocol: chat
 270                  */
 271
 272                 /*
 273                  * we have to take some care here to only take from the
 274                  * socket bytewise.  The browser may (and has been seen to
 275                  * in the case that onopen() performs websocket traffic)
 276                  * coalesce both handshake response and websocket traffic
 277                  * in one packet, since at that point the connection is
 278                  * definitively ready from browser pov.
 279                  */
 280                 len = 1;
 281                 while (wsi->u.hdr.parser_state != WSI_PARSING_COMPLETE &&
 282                        len > 0) {
 283                         n = lws_ssl_capable_read(wsi, &c, 1);
 284                         lws_latency(context, wsi, "send lws_issue_raw", n,
 285                                     n == 1);
 286                         switch (n) {
 287                         case 0:
 288                         case LWS_SSL_CAPABLE_ERROR:
 289                                 cce = "read failed";
 290                                 goto bail3;
 291                         case LWS_SSL_CAPABLE_MORE_SERVICE:
 292                                 return 0;
 293                         }
 294
 295                         if (lws_parse(wsi, c)) {
 296                                 lwsl_warn("problems parsing header\n");
 297                                 goto bail3;
 298                         }
 299                 }
 300
 301                 /*
 302                  * hs may also be coming in multiple packets, there is a 5-sec
 303                  * libwebsocket timeout still active here too, so if parsing did
 304                  * not complete just wait for next packet coming in this state
 305                  */
 306
 307                 if (wsi->u.hdr.parser_state != WSI_PARSING_COMPLETE)
 308                         break;
 309
 310                 /*
 311                  * otherwise deal with the handshake.  If there's any
 312                  * packet traffic already arrived we'll trigger poll() again
 313                  * right away and deal with it that way
 314                  */
 315
 316                 return lws_client_interpret_server_handshake(wsi);
 317
 318 bail3:
 319                 lwsl_info("closing conn at LWS_CONNMODE...SERVER_REPLY\n");
 320                 wsi->vhost->protocols[0].callback(wsi,
 321                         LWS_CALLBACK_CLIENT_CONNECTION_ERROR,
 322                         wsi->user_space, (void *)cce, cce ? strlen(cce) : 0);
 323                 wsi->already_did_cce = 1;
 324                 lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS);
 325                 return -1;
 326
 327         case LWSCM_WSCL_WAITING_EXTENSION_CONNECT:
 328                 lwsl_ext("LWSCM_WSCL_WAITING_EXTENSION_CONNECT\n");
 329                 break;
 330
 331         case LWSCM_WSCL_PENDING_CANDIDATE_CHILD:
 332                 lwsl_ext("LWSCM_WSCL_PENDING_CANDIDATE_CHILD\n");
 333                 break;
 334         default:
 335                 break;
 336         }
 337
 338         return 0;
 339 }
 340
 341 /*
 342  * In-place str to lower case
 343  */
 344
 345 static void
 346 strtolower(char *s)
 347 {
 348         while (*s) {
 349 #ifdef LWS_PLAT_OPTEE
 350                 int tolower_optee(int c);
 351                 *s = tolower_optee((int)*s);
 352 #else
 353                 *s = tolower((int)*s);
 354 #endif
 355                 s++;
 356         }
 357 }
 358
 359 int LWS_WARN_UNUSED_RESULT
 360 lws_http_transaction_completed_client(struct lws *wsi)
 361 {
 362         lwsl_debug("%s: wsi %p\n", __func__, wsi);
 363         /* if we can't go back to accept new headers, drop the connection */
 364         if (wsi->u.http.connection_type != HTTP_CONNECTION_KEEP_ALIVE) {
 365                 lwsl_info("%s: %p: close connection\n", __func__, wsi);
 366                 return 1;
 367         }
 368
 369         /* otherwise set ourselves up ready to go again */
 370         wsi->state = LWSS_CLIENT_HTTP_ESTABLISHED;
 371         wsi->mode = LWSCM_HTTP_CLIENT_ACCEPTED;
 372         wsi->u.http.content_length = 0;
 373         wsi->hdr_parsing_completed = 0;
 374
 375         /* He asked for it to stay alive indefinitely */
 376         lws_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
 377
 378         /*
 379          * As client, nothing new is going to come until we ask for it
 380          * we can drop the ah, if any
 381          */
 382         if (wsi->u.hdr.ah) {
 383                 wsi->u.hdr.ah->rxpos = wsi->u.hdr.ah->rxlen;
 384                 lws_header_table_detach(wsi, 0);
 385         }
 386
 387         /* If we're (re)starting on headers, need other implied init */
 388         wsi->u.hdr.ues = URIES_IDLE;
 389
 390         lwsl_info("%s: %p: keep-alive await new transaction\n", __func__, wsi);
 391
 392         return 0;
 393 }
 394
 395 LWS_VISIBLE LWS_EXTERN unsigned int
 396 lws_http_client_http_response(struct lws *wsi)
 397 {
 398         if (!wsi->u.http.ah)
 399                 return 0;
 400
 401         return wsi->u.http.ah->http_response;
 402 }
 403
 404 int
 405 lws_client_interpret_server_handshake(struct lws *wsi)
 406 {
 407         int n, len, okay = 0, port = 0, ssl = 0;
 408         int close_reason = LWS_CLOSE_STATUS_PROTOCOL_ERR;
 409         struct lws_context *context = wsi->context;
 410         const char *pc, *prot, *ads = NULL, *path, *cce = NULL;
 411         struct allocated_headers *ah = NULL;
 412         char *p;
 413 #ifndef LWS_NO_EXTENSIONS
 414         struct lws_context_per_thread *pt = &context->pt[(int)wsi->tsi];
 415         char *sb = (char *)&pt->serv_buf[0];
 416         const struct lws_ext_options *opts;
 417         const struct lws_extension *ext;
 418         char ext_name[128];
 419         const char *c, *a;
 420         char ignore;
 421         int more = 1;
 422         void *v;
 423 #endif
 424
 425         if (!wsi->do_ws) {
 426                 /* we are being an http client...
 427                  */
 428                 ah = wsi->u.hdr.ah;
 429                 lws_union_transition(wsi, LWSCM_HTTP_CLIENT_ACCEPTED);
 430                 wsi->state = LWSS_CLIENT_HTTP_ESTABLISHED;
 431                 wsi->u.http.ah = ah;
 432                 ah->http_response = 0;
 433         }
 434
 435         /*
 436          * well, what the server sent looked reasonable for syntax.
 437          * Now let's confirm it sent all the necessary headers
 438          *
 439          * http (non-ws) client will expect something like this
 440          *
 441          * HTTP/1.0.200
 442          * server:.libwebsockets
 443          * content-type:.text/html
 444          * content-length:.17703
 445          * set-cookie:.test=LWS_1456736240_336776_COOKIE;Max-Age=360000
 446          *
 447          *
 448          *
 449          */
 450
 451         wsi->u.http.connection_type = HTTP_CONNECTION_KEEP_ALIVE;
 452         p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_HTTP);
 453         if (wsi->do_ws && !p) {
 454                 lwsl_info("no URI\n");
 455                 cce = "HS: URI missing";
 456                 goto bail3;
 457         }
 458         if (!p) {
 459                 p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_HTTP1_0);
 460                 wsi->u.http.connection_type = HTTP_CONNECTION_CLOSE;
 461         }
 462         if (!p) {
 463                 cce = "HS: URI missing";
 464                 lwsl_info("no URI\n");
 465                 goto bail3;
 466         }
 467         n = atoi(p);
 468         if (ah)
 469                 ah->http_response = n;
 470
 471         if (n == 301 || n == 302 || n == 303 || n == 307 || n == 308) {
 472                 p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_HTTP_LOCATION);
 473                 if (!p) {
 474                         cce = "HS: Redirect code but no Location";
 475                         goto bail3;
 476                 }
 477
 478                 if (lws_parse_uri(p, &prot, &ads, &port, &path)) {
 479                         cce = "HS: URI did not parse";
 480                         goto bail3;
 481                 }
 482
 483                 if (!strcmp(prot, "wss") || !strcmp(prot, "https"))
 484                         ssl = 1;
 485
 486                 if (!lws_client_reset(wsi, ssl, ads, port, path, ads)) {
 487                         lwsl_err("Redirect failed\n");
 488                         cce = "HS: Redirect failed";
 489                         goto bail3;
 490                 }
 491                 return 0;
 492         }
 493
 494         if (!wsi->do_ws) {
 495                 if (n != 200 && n != 304) {
 496                         lwsl_notice("Connection failed with code %d\n", n);
 497                         cce = "HS: Server did not return 200 or 304";
 498                         goto bail2;
 499                 }
 500
 501 #ifdef LWS_WITH_HTTP_PROXY
 502                 wsi->perform_rewrite = 0;
 503                 if (lws_hdr_total_length(wsi, WSI_TOKEN_HTTP_CONTENT_TYPE)) {
 504                         if (!strncmp(lws_hdr_simple_ptr(wsi, WSI_TOKEN_HTTP_CONTENT_TYPE),
 505                                      "text/html", 9))
 506                                 wsi->perform_rewrite = 1;
 507                 }
 508 #endif
 509
 510                 /* allocate the per-connection user memory (if any) */
 511                 if (lws_ensure_user_space(wsi)) {
 512                         lwsl_err("Problem allocating wsi user mem\n");
 513                         cce = "HS: OOM";
 514                         goto bail2;
 515                 }
 516
 517                 /* he may choose to send us stuff in chunked transfer-coding */
 518                 wsi->chunked = 0;
 519                 wsi->chunk_remaining = 0; /* ie, next thing is chunk size */
 520                 if (lws_hdr_total_length(wsi, WSI_TOKEN_HTTP_TRANSFER_ENCODING)) {
 521                         wsi->chunked = !strcmp(lws_hdr_simple_ptr(wsi,
 522                                                WSI_TOKEN_HTTP_TRANSFER_ENCODING),
 523                                         "chunked");
 524                         /* first thing is hex, after payload there is crlf */
 525                         wsi->chunk_parser = ELCP_HEX;
 526                 }
 527
 528                 if (lws_hdr_total_length(wsi, WSI_TOKEN_HTTP_CONTENT_LENGTH)) {
 529                         wsi->u.http.content_length =
 530                                         atoi(lws_hdr_simple_ptr(wsi,
 531                                                 WSI_TOKEN_HTTP_CONTENT_LENGTH));
 532                         lwsl_notice("%s: incoming content length %d\n", __func__,
 533                                         wsi->u.http.content_length);
 534                         wsi->u.http.content_remain = wsi->u.http.content_length;
 535                 } else /* can't do 1.1 without a content length or chunked */
 536                         if (!wsi->chunked)
 537                                 wsi->u.http.connection_type = HTTP_CONNECTION_CLOSE;
 538
 539                 /*
 540                  * we seem to be good to go, give client last chance to check
 541                  * headers and OK it
 542                  */
 543                 if (wsi->protocol->callback(wsi, LWS_CALLBACK_CLIENT_FILTER_PRE_ESTABLISH,
 544                                             wsi->user_space, NULL, 0)) {
 545
 546                         cce = "HS: disallowed by client filter";
 547                         goto bail2;
 548                 }
 549
 550                 /* clear his proxy connection timeout */
 551                 lws_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
 552
 553                 wsi->rxflow_change_to = LWS_RXFLOW_ALLOW;
 554
 555                 /* call him back to inform him he is up */
 556                 if (wsi->protocol->callback(wsi,
 557                                             LWS_CALLBACK_ESTABLISHED_CLIENT_HTTP,
 558                                             wsi->user_space, NULL, 0)) {
 559                         cce = "HS: disallowed at ESTABLISHED";
 560                         goto bail3;
 561                 }
 562
 563                 /* free up his parsing allocations */
 564                 lws_header_table_detach(wsi, 0);
 565
 566                 lwsl_notice("%s: client connection up\n", __func__);
 567
 568                 return 0;
 569         }
 570
 571         if (lws_hdr_total_length(wsi, WSI_TOKEN_ACCEPT) == 0) {
 572                 lwsl_info("no ACCEPT\n");
 573                 cce = "HS: ACCEPT missing";
 574                 goto bail3;
 575         }
 576
 577         if (p && strncmp(p, "101", 3)) {
 578                 lwsl_warn(
 579                        "lws_client_handshake: got bad HTTP response '%s'\n", p);
 580                 cce = "HS: ws upgrade response not 101";
 581                 goto bail3;
 582         }
 583
 584         p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_UPGRADE);
 585         if (!p) {
 586                 lwsl_info("no UPGRADE\n");
 587                 cce = "HS: UPGRADE missing";
 588                 goto bail3;
 589         }
 590         strtolower(p);
 591         if (strcmp(p, "websocket")) {
 592                 lwsl_warn(
 593                       "lws_client_handshake: got bad Upgrade header '%s'\n", p);
 594                 cce = "HS: Upgrade to something other than websocket";
 595                 goto bail3;
 596         }
 597
 598         p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_CONNECTION);
 599         if (!p) {
 600                 lwsl_info("no Connection hdr\n");
 601                 cce = "HS: CONNECTION missing";
 602                 goto bail3;
 603         }
 604         strtolower(p);
 605         if (strcmp(p, "upgrade")) {
 606                 lwsl_warn("lws_client_int_s_hs: bad header %s\n", p);
 607                 cce = "HS: UPGRADE malformed";
 608                 goto bail3;
 609         }
 610
 611         pc = lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_SENT_PROTOCOLS);
 612         if (!pc) {
 613                 lwsl_parser("lws_client_int_s_hs: no protocol list\n");
 614         } else
 615                 lwsl_parser("lws_client_int_s_hs: protocol list '%s'\n", pc);
 616
 617         /*
 618          * confirm the protocol the server wants to talk was in the list
 619          * of protocols we offered
 620          */
 621
 622         len = lws_hdr_total_length(wsi, WSI_TOKEN_PROTOCOL);
 623         if (!len) {
 624                 lwsl_info("lws_client_int_s_hs: WSI_TOKEN_PROTOCOL is null\n");
 625                 /*
 626                  * no protocol name to work from,
 627                  * default to first protocol
 628                  */
 629                 n = 0;
 630                 wsi->protocol = &wsi->vhost->protocols[0];
 631                 goto check_extensions;
 632         }
 633
 634         p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_PROTOCOL);
 635         len = strlen(p);
 636
 637         while (pc && *pc && !okay) {
 638                 if (!strncmp(pc, p, len) &&
 639                     (pc[len] == ',' || pc[len] == '\0')) {
 640                         okay = 1;
 641                         continue;
 642                 }
 643                 while (*pc && *pc++ != ',')
 644                         ;
 645                 while (*pc && *pc == ' ')
 646                         pc++;
 647         }
 648
 649         if (!okay) {
 650                 lwsl_err("lws_client_int_s_hs: got bad protocol %s\n", p);
 651                 cce = "HS: PROTOCOL malformed";
 652                 goto bail2;
 653         }
 654
 655         /*
 656          * identify the selected protocol struct and set it
 657          */
 658         n = 0;
 659         wsi->protocol = NULL;
 660         while (wsi->vhost->protocols[n].callback && !wsi->protocol) {
 661                 if (strcmp(p, wsi->vhost->protocols[n].name) == 0) {
 662                         wsi->protocol = &wsi->vhost->protocols[n];
 663                         break;
 664                 }
 665                 n++;
 666         }
 667
 668         if (wsi->protocol == NULL) {
 669                 lwsl_err("lws_client_int_s_hs: fail protocol %s\n", p);
 670                 cce = "HS: Cannot match protocol";
 671                 goto bail2;
 672         }
 673
 674 check_extensions:
 675         /*
 676          * stitch protocol choice into the vh protocol linked list
 677          * We always insert ourselves at the start of the list
 678          *
 679          * X <-> B
 680          * X <-> pAn <-> pB
 681          */
 682         //lwsl_err("%s: pre insert vhost start wsi %p, that wsi prev == %p\n",
 683         //              __func__,
 684         //              wsi->vhost->same_vh_protocol_list[n],
 685         //              wsi->same_vh_protocol_prev);
 686         wsi->same_vh_protocol_prev = /* guy who points to us */
 687                 &wsi->vhost->same_vh_protocol_list[n];
 688         wsi->same_vh_protocol_next = /* old first guy is our next */
 689                         wsi->vhost->same_vh_protocol_list[n];
 690         /* we become the new first guy */
 691         wsi->vhost->same_vh_protocol_list[n] = wsi;
 692
 693         if (wsi->same_vh_protocol_next)
 694                 /* old first guy points back to us now */
 695                 wsi->same_vh_protocol_next->same_vh_protocol_prev =
 696                                 &wsi->same_vh_protocol_next;
 697
 698 #ifndef LWS_NO_EXTENSIONS
 699         /* instantiate the accepted extensions */
 700
 701         if (!lws_hdr_total_length(wsi, WSI_TOKEN_EXTENSIONS)) {
 702                 lwsl_ext("no client extensions allowed by server\n");
 703                 goto check_accept;
 704         }
 705
 706         /*
 707          * break down the list of server accepted extensions
 708          * and go through matching them or identifying bogons
 709          */
 710
 711         if (lws_hdr_copy(wsi, sb, context->pt_serv_buf_size, WSI_TOKEN_EXTENSIONS) < 0) {
 712                 lwsl_warn("ext list from server failed to copy\n");
 713                 cce = "HS: EXT: list too big";
 714                 goto bail2;
 715         }
 716
 717         c = sb;
 718         n = 0;
 719         ignore = 0;
 720         a = NULL;
 721         while (more) {
 722
 723                 if (*c && (*c != ',' && *c != '\t')) {
 724                         if (*c == ';') {
 725                                 ignore = 1;
 726                                 if (!a)
 727                                         a = c + 1;
 728                         }
 729                         if (ignore || *c == ' ') {
 730                                 c++;
 731                                 continue;
 732                         }
 733
 734                         ext_name[n] = *c++;
 735                         if (n < sizeof(ext_name) - 1)
 736                                 n++;
 737                         continue;
 738                 }
 739                 ext_name[n] = '\0';
 740                 ignore = 0;
 741                 if (!*c)
 742                         more = 0;
 743                 else {
 744                         c++;
 745                         if (!n)
 746                                 continue;
 747                 }
 748
 749                 /* check we actually support it */
 750
 751                 lwsl_notice("checking client ext %s\n", ext_name);
 752
 753                 n = 0;
 754                 ext = wsi->vhost->extensions;
 755                 while (ext && ext->callback) {
 756                         if (strcmp(ext_name, ext->name)) {
 757                                 ext++;
 758                                 continue;
 759                         }
 760
 761                         n = 1;
 762                         lwsl_notice("instantiating client ext %s\n", ext_name);
 763
 764                         /* instantiate the extension on this conn */
 765
 766                         wsi->active_extensions[wsi->count_act_ext] = ext;
 767
 768                         /* allow him to construct his ext instance */
 769
 770                         if (ext->callback(lws_get_context(wsi), ext, wsi,
 771                                       LWS_EXT_CB_CLIENT_CONSTRUCT,
 772                                       (void *)&wsi->act_ext_user[wsi->count_act_ext],
 773                                       (void *)&opts, 0)) {
 774                                 lwsl_notice(" ext %s failed construction\n", ext_name);
 775                                 ext++;
 776                                 continue;
 777                         }
 778
 779                         /*
 780                          * allow the user code to override ext defaults if it
 781                          * wants to
 782                          */
 783                         ext_name[0] = '\0';
 784                         if (user_callback_handle_rxflow(wsi->protocol->callback,
 785                                         wsi, LWS_CALLBACK_WS_EXT_DEFAULTS,
 786                                         (char *)ext->name, ext_name,
 787                                         sizeof(ext_name))) {
 788                                 cce = "HS: EXT: failed setting defaults";
 789                                 goto bail2;
 790                         }
 791
 792                         if (ext_name[0] &&
 793                             lws_ext_parse_options(ext, wsi, wsi->act_ext_user[
 794                                                   wsi->count_act_ext], opts, ext_name,
 795                                                   strlen(ext_name))) {
 796                                 lwsl_err("%s: unable to parse user defaults '%s'",
 797                                          __func__, ext_name);
 798                                 cce = "HS: EXT: failed parsing defaults";
 799                                 goto bail2;
 800                         }
 801
 802                         /*
 803                          * give the extension the server options
 804                          */
 805                         if (a && lws_ext_parse_options(ext, wsi,
 806                                         wsi->act_ext_user[wsi->count_act_ext],
 807                                         opts, a, c - a)) {
 808                                 lwsl_err("%s: unable to parse remote def '%s'",
 809                                          __func__, a);
 810                                 cce = "HS: EXT: failed parsing options";
 811                                 goto bail2;
 812                         }
 813
 814                         if (ext->callback(lws_get_context(wsi), ext, wsi,
 815                                         LWS_EXT_CB_OPTION_CONFIRM,
 816                                       wsi->act_ext_user[wsi->count_act_ext],
 817                                       NULL, 0)) {
 818                                 lwsl_err("%s: ext %s rejects server options %s",
 819                                          __func__, ext->name, a);
 820                                 cce = "HS: EXT: Rejects server options";
 821                                 goto bail2;
 822                         }
 823
 824                         wsi->count_act_ext++;
 825
 826                         ext++;
 827                 }
 828
 829                 if (n == 0) {
 830                         lwsl_warn("Unknown ext '%s'!\n", ext_name);
 831                         cce = "HS: EXT: unknown ext";
 832                         goto bail2;
 833                 }
 834
 835                 a = NULL;
 836                 n = 0;
 837         }
 838
 839 check_accept:
 840 #endif
 841
 842         /*
 843          * Confirm his accept token is the one we precomputed
 844          */
 845
 846         p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_ACCEPT);
 847         if (strcmp(p, wsi->u.hdr.ah->initial_handshake_hash_base64)) {
 848                 lwsl_warn("lws_client_int_s_hs: accept '%s' wrong vs '%s'\n", p,
 849                                   wsi->u.hdr.ah->initial_handshake_hash_base64);
 850                 cce = "HS: Accept hash wrong";
 851                 goto bail2;
 852         }
 853
 854         /* allocate the per-connection user memory (if any) */
 855         if (lws_ensure_user_space(wsi)) {
 856                 lwsl_err("Problem allocating wsi user mem\n");
 857                 cce = "HS: OOM";
 858                 goto bail2;
 859         }
 860
 861         /*
 862          * we seem to be good to go, give client last chance to check
 863          * headers and OK it
 864          */
 865         if (wsi->protocol->callback(wsi, LWS_CALLBACK_CLIENT_FILTER_PRE_ESTABLISH,
 866                                     wsi->user_space, NULL, 0)) {
 867                 cce = "HS: Rejected by filter cb";
 868                 goto bail2;
 869         }
 870
 871         /* clear his proxy connection timeout */
 872         lws_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
 873
 874         /* free up his parsing allocations */
 875         lws_header_table_detach(wsi, 0);
 876
 877         lws_union_transition(wsi, LWSCM_WS_CLIENT);
 878         wsi->state = LWSS_ESTABLISHED;
 879         lws_restart_ws_ping_pong_timer(wsi);
 880
 881         wsi->rxflow_change_to = LWS_RXFLOW_ALLOW;
 882
 883         /*
 884          * create the frame buffer for this connection according to the
 885          * size mentioned in the protocol definition.  If 0 there, then
 886          * use a big default for compatibility
 887          */
 888         n = wsi->protocol->rx_buffer_size;
 889         if (!n)
 890                 n = context->pt_serv_buf_size;
 891         n += LWS_PRE;
 892         wsi->u.ws.rx_ubuf = lws_malloc(n + 4 /* 0x0000ffff zlib */);
 893         if (!wsi->u.ws.rx_ubuf) {
 894                 lwsl_err("Out of Mem allocating rx buffer %d\n", n);
 895                 cce = "HS: OOM";
 896                 goto bail2;
 897         }
 898        wsi->u.ws.rx_ubuf_alloc = n;
 899         lwsl_info("Allocating client RX buffer %d\n", n);
 900
 901         if (setsockopt(wsi->sock, SOL_SOCKET, SO_SNDBUF, (const char *)&n,
 902                        sizeof n)) {
 903                 lwsl_warn("Failed to set SNDBUF to %d", n);
 904                 cce = "HS: SO_SNDBUF failed";
 905                 goto bail3;
 906         }
 907
 908         lwsl_debug("handshake OK for protocol %s\n", wsi->protocol->name);
 909
 910         /* call him back to inform him he is up */
 911
 912         if (wsi->protocol->callback(wsi, LWS_CALLBACK_CLIENT_ESTABLISHED,
 913                                     wsi->user_space, NULL, 0)) {
 914                 cce = "HS: Rejected at CLIENT_ESTABLISHED";
 915                 goto bail3;
 916         }
 917 #ifndef LWS_NO_EXTENSIONS
 918         /*
 919          * inform all extensions, not just active ones since they
 920          * already know
 921          */
 922         ext = wsi->vhost->extensions;
 923
 924         while (ext && ext->callback) {
 925                 v = NULL;
 926                 for (n = 0; n < wsi->count_act_ext; n++)
 927                         if (wsi->active_extensions[n] == ext)
 928                                 v = wsi->act_ext_user[n];
 929
 930                 ext->callback(context, ext, wsi,
 931                           LWS_EXT_CB_ANY_WSI_ESTABLISHED, v, NULL, 0);
 932                 ext++;
 933         }
 934 #endif
 935
 936         return 0;
 937
 938 bail3:
 939         close_reason = LWS_CLOSE_STATUS_NOSTATUS;
 940
 941 bail2:
 942         if (wsi->protocol)
 943                 wsi->protocol->callback(wsi, LWS_CALLBACK_CLIENT_CONNECTION_ERROR,
 944                                 wsi->user_space, (void *)cce,
 945                                 (unsigned int)strlen(cce));
 946         wsi->already_did_cce = 1;
 947
 948         lwsl_info("closing connection due to bail2 connection error\n");
 949
 950         /* closing will free up his parsing allocations */
 951         lws_close_free_wsi(wsi, close_reason);
 952
 953         return 1;
 954 }
 955
 956
 957 char *
 958 lws_generate_client_handshake(struct lws *wsi, char *pkt)
 959 {
 960         char buf[128], hash[20], key_b64[40], *p = pkt;
 961         struct lws_context *context = wsi->context;
 962         const char *meth;
 963         int n;
 964 #ifndef LWS_NO_EXTENSIONS
 965         const struct lws_extension *ext;
 966         int ext_count = 0;
 967 #endif
 968
 969         meth = lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_METHOD);
 970         if (!meth) {
 971                 meth = "GET";
 972                 wsi->do_ws = 1;
 973         } else
 974                 wsi->do_ws = 0;
 975
 976         if (wsi->do_ws) {
 977                 /*
 978                  * create the random key
 979                  */
 980                 n = lws_get_random(context, hash, 16);
 981                 if (n != 16) {
 982                         lwsl_err("Unable to read from random dev %s\n",
 983                                  SYSTEM_RANDOM_FILEPATH);
 984                         lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS);
 985                         return NULL;
 986                 }
 987
 988                 lws_b64_encode_string(hash, 16, key_b64, sizeof(key_b64));
 989         }
 990
 991         /*
 992          * 04 example client handshake
 993          *
 994          * GET /chat HTTP/1.1
 995          * Host: server.example.com
 996          * Upgrade: websocket
 997          * Connection: Upgrade
 998          * Sec-WebSocket-Key: dGhlIHNhbXBsZSBub25jZQ==
 999          * Sec-WebSocket-Origin: http://example.com
1000          * Sec-WebSocket-Protocol: chat, superchat
1001          * Sec-WebSocket-Version: 4
1002          */
1003
1004         p += sprintf(p, "%s %s HTTP/1.1\x0d\x0a", meth,
1005                      lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_URI));
1006
1007         p += sprintf(p, "Pragma: no-cache\x0d\x0a"
1008                         "Cache-Control: no-cache\x0d\x0a");
1009
1010         p += sprintf(p, "Host: %s\x0d\x0a",
1011                      lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_HOST));
1012
1013         if (lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_ORIGIN)) {
1014                 if (lws_check_opt(context->options, LWS_SERVER_OPTION_JUST_USE_RAW_ORIGIN))
1015                         p += sprintf(p, "Origin: %s\x0d\x0a",
1016                                      lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_ORIGIN));
1017                 else
1018                         p += sprintf(p, "Origin: http://%s\x0d\x0a",
1019                                      lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_ORIGIN));
1020         }
1021
1022         if (wsi->do_ws) {
1023                 p += sprintf(p, "Upgrade: websocket\x0d\x0a"
1024                                 "Connection: Upgrade\x0d\x0a"
1025                                 "Sec-WebSocket-Key: ");
1026                 strcpy(p, key_b64);
1027                 p += strlen(key_b64);
1028                 p += sprintf(p, "\x0d\x0a");
1029                 if (lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_SENT_PROTOCOLS))
1030                         p += sprintf(p, "Sec-WebSocket-Protocol: %s\x0d\x0a",
1031                              lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_SENT_PROTOCOLS));
1032
1033                 /* tell the server what extensions we could support */
1034
1035 #ifndef LWS_NO_EXTENSIONS
1036                 ext = wsi->vhost->extensions;
1037                 while (ext && ext->callback) {
1038                         n = lws_ext_cb_all_exts(context, wsi,
1039                                    LWS_EXT_CB_CHECK_OK_TO_PROPOSE_EXTENSION,
1040                                    (char *)ext->name, 0);
1041                         if (n) { /* an extension vetos us */
1042                                 lwsl_ext("ext %s vetoed\n", (char *)ext->name);
1043                                 ext++;
1044                                 continue;
1045                         }
1046                         n = wsi->vhost->protocols[0].callback(wsi,
1047                                 LWS_CALLBACK_CLIENT_CONFIRM_EXTENSION_SUPPORTED,
1048                                         wsi->user_space, (char *)ext->name, 0);
1049
1050                         /*
1051                          * zero return from callback means
1052                          * go ahead and allow the extension,
1053                          * it's what we get if the callback is
1054                          * unhandled
1055                          */
1056
1057                         if (n) {
1058                                 ext++;
1059                                 continue;
1060                         }
1061
1062                         /* apply it */
1063
1064                         if (ext_count)
1065                                 *p++ = ',';
1066                         else
1067                                 p += sprintf(p, "Sec-WebSocket-Extensions: ");
1068                         p += sprintf(p, "%s", ext->client_offer);
1069                         ext_count++;
1070
1071                         ext++;
1072                 }
1073                 if (ext_count)
1074                         p += sprintf(p, "\x0d\x0a");
1075 #endif
1076
1077                 if (wsi->ietf_spec_revision)
1078                         p += sprintf(p, "Sec-WebSocket-Version: %d\x0d\x0a",
1079                                      wsi->ietf_spec_revision);
1080
1081                 /* prepare the expected server accept response */
1082
1083                 key_b64[39] = '\0'; /* enforce composed length below buf sizeof */
1084                 n = sprintf(buf, "%s258EAFA5-E914-47DA-95CA-C5AB0DC85B11", key_b64);
1085
1086                 lws_SHA1((unsigned char *)buf, n, (unsigned char *)hash);
1087
1088                 lws_b64_encode_string(hash, 20,
1089                                       wsi->u.hdr.ah->initial_handshake_hash_base64,
1090                                       sizeof(wsi->u.hdr.ah->initial_handshake_hash_base64));
1091         }
1092
1093         /* give userland a chance to append, eg, cookies */
1094
1095         wsi->vhost->protocols[0].callback(wsi, LWS_CALLBACK_CLIENT_APPEND_HANDSHAKE_HEADER,
1096                                 wsi->user_space, &p, (pkt + context->pt_serv_buf_size) - p - 12);
1097
1098         p += sprintf(p, "\x0d\x0a");
1099
1100         return p;
1101 }
1102