lib/server.c

   1 /*
   2  * libwebsockets - small server side websockets and web server implementation
   3  *
   4  * Copyright (C) 2010-2016 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
  23 #include "private-libwebsockets.h"
  24
  25 int
  26 lws_context_init_server(struct lws_context_creation_info *info,
  27                         struct lws_context *context)
  28 {
  29 #ifdef LWS_USE_IPV6
  30         struct sockaddr_in6 serv_addr6;
  31 #endif
  32 #if LWS_POSIX
  33         struct sockaddr_in serv_addr4;
  34         socklen_t len = sizeof(struct sockaddr);
  35         int n, opt = 1, limit = 1;
  36         struct sockaddr_in sin;
  37         struct sockaddr *v;
  38 #endif
  39         lws_sockfd_type sockfd;
  40         struct lws *wsi;
  41         int m = 0;
  42
  43         /* set up our external listening socket we serve on */
  44
  45         if (info->port == CONTEXT_PORT_NO_LISTEN)
  46                 return 0;
  47
  48 #if LWS_POSIX
  49 #if defined(__linux__)
  50         limit = context->count_threads;
  51 #endif
  52
  53         for (m = 0; m < limit; m++) {
  54 #ifdef LWS_USE_IPV6
  55         if (LWS_IPV6_ENABLED(context))
  56                 sockfd = socket(AF_INET6, SOCK_STREAM, 0);
  57         else
  58 #endif
  59                 sockfd = socket(AF_INET, SOCK_STREAM, 0);
  60
  61         if (sockfd == -1) {
  62 #else
  63         sockfd = mbed3_create_tcp_stream_socket();
  64         if (!lws_sockfd_valid(sockfd)) {
  65 #endif
  66                 lwsl_err("ERROR opening socket\n");
  67                 return 1;
  68         }
  69
  70 #if LWS_POSIX
  71         /*
  72          * allow us to restart even if old sockets in TIME_WAIT
  73          */
  74         if (setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR,
  75                        (const void *)&opt, sizeof(opt)) < 0) {
  76                 compatible_close(sockfd);
  77                 return 1;
  78         }
  79 #if defined(__linux__) && defined(SO_REUSEPORT) && LWS_MAX_SMP > 1
  80         if (context->count_threads > 1)
  81                 if (setsockopt(sockfd, SOL_SOCKET, SO_REUSEPORT,
  82                                 (const void *)&opt, sizeof(opt)) < 0) {
  83                         compatible_close(sockfd);
  84                         return 1;
  85                 }
  86 #endif
  87 #endif
  88         lws_plat_set_socket_options(context, sockfd);
  89
  90 #if LWS_POSIX
  91 #ifdef LWS_USE_IPV6
  92         if (LWS_IPV6_ENABLED(context)) {
  93                 v = (struct sockaddr *)&serv_addr6;
  94                 n = sizeof(struct sockaddr_in6);
  95                 bzero((char *) &serv_addr6, sizeof(serv_addr6));
  96                 serv_addr6.sin6_addr = in6addr_any;
  97                 serv_addr6.sin6_family = AF_INET6;
  98                 serv_addr6.sin6_port = htons(info->port);
  99         } else
 100 #endif
 101         {
 102                 v = (struct sockaddr *)&serv_addr4;
 103                 n = sizeof(serv_addr4);
 104                 bzero((char *) &serv_addr4, sizeof(serv_addr4));
 105                 serv_addr4.sin_addr.s_addr = INADDR_ANY;
 106                 serv_addr4.sin_family = AF_INET;
 107
 108                 if (info->iface && interface_to_sa(context, info->iface,
 109                                    (struct sockaddr_in *)v, n) < 0) {
 110                         lwsl_err("Unable to find interface %s\n", info->iface);
 111                         goto bail;
 112                 }
 113
 114                 serv_addr4.sin_port = htons(info->port);
 115         } /* ipv4 */
 116
 117         n = bind(sockfd, v, n);
 118         if (n < 0) {
 119                 lwsl_err("ERROR on binding to port %d (%d %d)\n",
 120                                               info->port, n, LWS_ERRNO);
 121                 goto bail;
 122         }
 123
 124         if (getsockname(sockfd, (struct sockaddr *)&sin, &len) == -1)
 125                 lwsl_warn("getsockname: %s\n", strerror(LWS_ERRNO));
 126         else
 127                 info->port = ntohs(sin.sin_port);
 128 #endif
 129         context->listen_port = info->port;
 130
 131         wsi = lws_zalloc(sizeof(struct lws));
 132         if (wsi == NULL) {
 133                 lwsl_err("Out of mem\n");
 134                 goto bail;
 135         }
 136         wsi->context = context;
 137         wsi->sock = sockfd;
 138         wsi->mode = LWSCM_SERVER_LISTENER;
 139         wsi->protocol = context->protocols;
 140         wsi->tsi = m;
 141
 142         context->pt[m].wsi_listening = wsi;
 143         if (insert_wsi_socket_into_fds(context, wsi))
 144                 goto bail;
 145
 146         context->count_wsi_allocated++;
 147         context->pt[m].lserv_fd = sockfd;
 148
 149 #if LWS_POSIX
 150         listen(wsi->sock, LWS_SOMAXCONN);
 151         } /* for each thread able to independently lister */
 152 #else
 153         mbed3_tcp_stream_bind(wsi->sock, info->port, wsi);
 154 #endif
 155         lwsl_notice(" Listening on port %d\n", info->port);
 156
 157         return 0;
 158
 159 bail:
 160         compatible_close(sockfd);
 161
 162         return 1;
 163 }
 164
 165 int
 166 _lws_server_listen_accept_flow_control(struct lws *twsi, int on)
 167 {
 168         struct lws_context_per_thread *pt = &twsi->context->pt[(int)twsi->tsi];
 169         struct lws *wsi = pt->wsi_listening;
 170         int n;
 171
 172         if (!wsi || twsi->context->being_destroyed)
 173                 return 0;
 174
 175         lwsl_debug("%s: Thr %d: LISTEN wsi %p: state %d\n",
 176                    __func__, twsi->tsi, (void *)wsi, on);
 177
 178         if (on)
 179                 n = lws_change_pollfd(wsi, 0, LWS_POLLIN);
 180         else
 181                 n = lws_change_pollfd(wsi, LWS_POLLIN, 0);
 182
 183         return n;
 184 }
 185
 186 int
 187 lws_http_action(struct lws *wsi)
 188 {
 189         enum http_connection_type connection_type;
 190         enum http_version request_version;
 191         char content_length_str[32];
 192         unsigned int n, count = 0;
 193         char http_version_str[10];
 194         char http_conn_str[20];
 195         int http_version_len;
 196         char *uri_ptr = NULL;
 197         int uri_len = 0;
 198
 199         static const unsigned char methods[] = {
 200                 WSI_TOKEN_GET_URI,
 201                 WSI_TOKEN_POST_URI,
 202                 WSI_TOKEN_OPTIONS_URI,
 203                 WSI_TOKEN_PUT_URI,
 204                 WSI_TOKEN_PATCH_URI,
 205                 WSI_TOKEN_DELETE_URI,
 206 #ifdef LWS_USE_HTTP2
 207                 WSI_TOKEN_HTTP_COLON_PATH,
 208 #endif
 209         };
 210 #ifdef _DEBUG
 211         static const char * const method_names[] = {
 212                 "GET", "POST", "OPTIONS", "PUT", "PATCH", "DELETE",
 213 #ifdef LWS_USE_HTTP2
 214                 ":path",
 215 #endif
 216         };
 217 #endif
 218
 219         /* it's not websocket.... shall we accept it as http? */
 220
 221         for (n = 0; n < ARRAY_SIZE(methods); n++)
 222                 if (lws_hdr_total_length(wsi, methods[n]))
 223                         count++;
 224         if (!count) {
 225                 lwsl_warn("Missing URI in HTTP request\n");
 226                 goto bail_nuke_ah;
 227         }
 228
 229         if (count != 1) {
 230                 lwsl_warn("multiple methods?\n");
 231                 goto bail_nuke_ah;
 232         }
 233
 234         if (lws_ensure_user_space(wsi))
 235                 goto bail_nuke_ah;
 236
 237         for (n = 0; n < ARRAY_SIZE(methods); n++)
 238                 if (lws_hdr_total_length(wsi, methods[n])) {
 239                         uri_ptr = lws_hdr_simple_ptr(wsi, methods[n]);
 240                         uri_len = lws_hdr_total_length(wsi, methods[n]);
 241                         lwsl_info("Method: %s request for '%s'\n",
 242                                         method_names[n], uri_ptr);
 243                         break;
 244                 }
 245
 246         /* we insist on absolute paths */
 247
 248         if (uri_ptr[0] != '/') {
 249                 lws_return_http_status(wsi, HTTP_STATUS_FORBIDDEN, NULL);
 250
 251                 goto bail_nuke_ah;
 252         }
 253
 254         /* HTTP header had a content length? */
 255
 256         wsi->u.http.content_length = 0;
 257         if (lws_hdr_total_length(wsi, WSI_TOKEN_POST_URI) ||
 258                 lws_hdr_total_length(wsi, WSI_TOKEN_PATCH_URI) ||
 259                 lws_hdr_total_length(wsi, WSI_TOKEN_PUT_URI))
 260                 wsi->u.http.content_length = 100 * 1024 * 1024;
 261
 262         if (lws_hdr_total_length(wsi, WSI_TOKEN_HTTP_CONTENT_LENGTH)) {
 263                 lws_hdr_copy(wsi, content_length_str,
 264                              sizeof(content_length_str) - 1,
 265                              WSI_TOKEN_HTTP_CONTENT_LENGTH);
 266                 wsi->u.http.content_length = atoi(content_length_str);
 267         }
 268
 269         /* http_version? Default to 1.0, override with token: */
 270         request_version = HTTP_VERSION_1_0;
 271
 272         /* Works for single digit HTTP versions. : */
 273         http_version_len = lws_hdr_total_length(wsi, WSI_TOKEN_HTTP);
 274         if (http_version_len > 7) {
 275                 lws_hdr_copy(wsi, http_version_str,
 276                                 sizeof(http_version_str) - 1, WSI_TOKEN_HTTP);
 277                 if (http_version_str[5] == '1' && http_version_str[7] == '1')
 278                         request_version = HTTP_VERSION_1_1;
 279         }
 280         wsi->u.http.request_version = request_version;
 281
 282         /* HTTP/1.1 defaults to "keep-alive", 1.0 to "close" */
 283         if (request_version == HTTP_VERSION_1_1)
 284                 connection_type = HTTP_CONNECTION_KEEP_ALIVE;
 285         else
 286                 connection_type = HTTP_CONNECTION_CLOSE;
 287
 288         /* Override default if http "Connection:" header: */
 289         if (lws_hdr_total_length(wsi, WSI_TOKEN_CONNECTION)) {
 290                 lws_hdr_copy(wsi, http_conn_str, sizeof(http_conn_str) - 1,
 291                              WSI_TOKEN_CONNECTION);
 292                 http_conn_str[sizeof(http_conn_str) - 1] = '\0';
 293                 if (!strcasecmp(http_conn_str, "keep-alive"))
 294                         connection_type = HTTP_CONNECTION_KEEP_ALIVE;
 295                 else
 296                         if (!strcasecmp(http_conn_str, "close"))
 297                                 connection_type = HTTP_CONNECTION_CLOSE;
 298         }
 299         wsi->u.http.connection_type = connection_type;
 300
 301         n = wsi->protocol->callback(wsi, LWS_CALLBACK_FILTER_HTTP_CONNECTION,
 302                                     wsi->user_space, uri_ptr, uri_len);
 303         if (n) {
 304                 lwsl_info("LWS_CALLBACK_HTTP closing\n");
 305
 306                 return 1;
 307         }
 308         /*
 309          * if there is content supposed to be coming,
 310          * put a timeout on it having arrived
 311          */
 312         lws_set_timeout(wsi, PENDING_TIMEOUT_HTTP_CONTENT,
 313                         wsi->context->timeout_secs);
 314
 315         n = wsi->protocol->callback(wsi, LWS_CALLBACK_HTTP,
 316                                     wsi->user_space, uri_ptr, uri_len);
 317         if (n) {
 318                 lwsl_info("LWS_CALLBACK_HTTP closing\n");
 319
 320                 return 1;
 321         }
 322
 323         /*
 324          * If we're not issuing a file, check for content_length or
 325          * HTTP keep-alive. No keep-alive header allocation for
 326          * ISSUING_FILE, as this uses HTTP/1.0.
 327          *
 328          * In any case, return 0 and let lws_read decide how to
 329          * proceed based on state
 330          */
 331         if (wsi->state != LWSS_HTTP_ISSUING_FILE)
 332                 /* Prepare to read body if we have a content length: */
 333                 if (wsi->u.http.content_length > 0)
 334                         wsi->state = LWSS_HTTP_BODY;
 335
 336         return 0;
 337
 338 bail_nuke_ah:
 339         /* we're closing, losing some rx is OK */
 340         wsi->u.hdr.ah->rxpos = wsi->u.hdr.ah->rxlen;
 341         lws_header_table_detach(wsi);
 342
 343         return 1;
 344 }
 345
 346
 347 int
 348 lws_handshake_server(struct lws *wsi, unsigned char **buf, size_t len)
 349 {
 350         struct lws_context *context = lws_get_context(wsi);
 351         struct lws_context_per_thread *pt = &context->pt[(int)wsi->tsi];
 352         struct _lws_header_related hdr;
 353         struct allocated_headers *ah;
 354         int protocol_len, n, hit;
 355         char protocol_list[128];
 356         char protocol_name[32];
 357         char *p;
 358
 359         assert(len < 10000000);
 360         assert(wsi->u.hdr.ah);
 361
 362         while (len--) {
 363                 wsi->more_rx_waiting = !!len;
 364
 365                 assert(wsi->mode == LWSCM_HTTP_SERVING);
 366
 367                 if (lws_parse(wsi, *(*buf)++)) {
 368                         lwsl_info("lws_parse failed\n");
 369                         goto bail_nuke_ah;
 370                 }
 371
 372                 if (wsi->u.hdr.parser_state != WSI_PARSING_COMPLETE)
 373                         continue;
 374
 375                 lwsl_parser("%s: lws_parse sees parsing complete\n", __func__);
 376                 lwsl_debug("%s: wsi->more_rx_waiting=%d\n", __func__,
 377                                 wsi->more_rx_waiting);
 378
 379                 wsi->mode = LWSCM_PRE_WS_SERVING_ACCEPT;
 380                 lws_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
 381
 382                 /* is this websocket protocol or normal http 1.0? */
 383
 384                 if (lws_hdr_total_length(wsi, WSI_TOKEN_UPGRADE)) {
 385                         if (!strcasecmp(lws_hdr_simple_ptr(wsi, WSI_TOKEN_UPGRADE),
 386                                         "websocket")) {
 387                                 lwsl_info("Upgrade to ws\n");
 388                                 goto upgrade_ws;
 389                         }
 390 #ifdef LWS_USE_HTTP2
 391                         if (!strcasecmp(lws_hdr_simple_ptr(wsi, WSI_TOKEN_UPGRADE),
 392                                         "h2c-14")) {
 393                                 lwsl_info("Upgrade to h2c-14\n");
 394                                 goto upgrade_h2c;
 395                         }
 396 #endif
 397                         lwsl_err("Unknown upgrade\n");
 398                         /* dunno what he wanted to upgrade to */
 399                         goto bail_nuke_ah;
 400                 }
 401
 402                 /* no upgrade ack... he remained as HTTP */
 403
 404                 lwsl_info("No upgrade\n");
 405                 ah = wsi->u.hdr.ah;
 406
 407                 lws_union_transition(wsi, LWSCM_HTTP_SERVING_ACCEPTED);
 408                 wsi->state = LWSS_HTTP;
 409                 wsi->u.http.fd = LWS_INVALID_FILE;
 410
 411                 /* expose it at the same offset as u.hdr */
 412                 wsi->u.http.ah = ah;
 413                 lwsl_debug("%s: wsi %p: ah %p\n", __func__, (void *)wsi, (void *)wsi->u.hdr.ah);
 414
 415                 n = lws_http_action(wsi);
 416
 417                 return n;
 418
 419 #ifdef LWS_USE_HTTP2
 420 upgrade_h2c:
 421                 if (!lws_hdr_total_length(wsi, WSI_TOKEN_HTTP2_SETTINGS)) {
 422                         lwsl_err("missing http2_settings\n");
 423                         goto bail_nuke_ah;
 424                 }
 425
 426                 lwsl_err("h2c upgrade...\n");
 427
 428                 p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_HTTP2_SETTINGS);
 429                 /* convert the peer's HTTP-Settings */
 430                 n = lws_b64_decode_string(p, protocol_list,
 431                                           sizeof(protocol_list));
 432                 if (n < 0) {
 433                         lwsl_parser("HTTP2_SETTINGS too long\n");
 434                         return 1;
 435                 }
 436
 437                 /* adopt the header info */
 438
 439                 ah = wsi->u.hdr.ah;
 440
 441                 lws_union_transition(wsi, LWSCM_HTTP2_SERVING);
 442
 443                 /* http2 union member has http union struct at start */
 444                 wsi->u.http.ah = ah;
 445
 446                 lws_http2_init(&wsi->u.http2.peer_settings);
 447                 lws_http2_init(&wsi->u.http2.my_settings);
 448
 449                 /* HTTP2 union */
 450
 451                 lws_http2_interpret_settings_payload(&wsi->u.http2.peer_settings,
 452                                 (unsigned char *)protocol_list, n);
 453
 454                 strcpy(protocol_list,
 455                        "HTTP/1.1 101 Switching Protocols\x0d\x0a"
 456                       "Connection: Upgrade\x0d\x0a"
 457                       "Upgrade: h2c\x0d\x0a\x0d\x0a");
 458                 n = lws_issue_raw(wsi, (unsigned char *)protocol_list,
 459                                         strlen(protocol_list));
 460                 if (n != strlen(protocol_list)) {
 461                         lwsl_debug("http2 switch: ERROR writing to socket\n");
 462                         return 1;
 463                 }
 464
 465                 wsi->state = LWSS_HTTP2_AWAIT_CLIENT_PREFACE;
 466
 467                 return 0;
 468 #endif
 469
 470 upgrade_ws:
 471                 if (!wsi->protocol)
 472                         lwsl_err("NULL protocol at lws_read\n");
 473
 474                 /*
 475                  * It's websocket
 476                  *
 477                  * Select the first protocol we support from the list
 478                  * the client sent us.
 479                  *
 480                  * Copy it to remove header fragmentation
 481                  */
 482
 483                 if (lws_hdr_copy(wsi, protocol_list, sizeof(protocol_list) - 1,
 484                                  WSI_TOKEN_PROTOCOL) < 0) {
 485                         lwsl_err("protocol list too long");
 486                         goto bail_nuke_ah;
 487                 }
 488
 489                 protocol_len = lws_hdr_total_length(wsi, WSI_TOKEN_PROTOCOL);
 490                 protocol_list[protocol_len] = '\0';
 491                 p = protocol_list;
 492                 hit = 0;
 493
 494                 while (*p && !hit) {
 495                         unsigned int n = 0;
 496                         while (n < sizeof(protocol_name) - 1 && *p && *p !=',')
 497                                 protocol_name[n++] = *p++;
 498                         protocol_name[n] = '\0';
 499                         if (*p)
 500                                 p++;
 501
 502                         lwsl_info("checking %s\n", protocol_name);
 503
 504                         n = 0;
 505                         while (context->protocols[n].callback) {
 506                                 if (context->protocols[n].name &&
 507                                     !strcmp(context->protocols[n].name,
 508                                             protocol_name)) {
 509                                         lwsl_info("prot match %d\n", n);
 510                                         wsi->protocol = &context->protocols[n];
 511                                         hit = 1;
 512                                         break;
 513                                 }
 514
 515                                 n++;
 516                         }
 517                 }
 518
 519                 /* we didn't find a protocol he wanted? */
 520
 521                 if (!hit) {
 522                         if (lws_hdr_simple_ptr(wsi, WSI_TOKEN_PROTOCOL)) {
 523                                 lwsl_err("No protocol from \"%s\" supported\n",
 524                                          protocol_list);
 525                                 goto bail_nuke_ah;
 526                         }
 527                         /*
 528                          * some clients only have one protocol and
 529                          * do not sent the protocol list header...
 530                          * allow it and match to protocol 0
 531                          */
 532                         lwsl_info("defaulting to prot 0 handler\n");
 533                         wsi->protocol = &context->protocols[0];
 534                 }
 535
 536                 /* allocate wsi->user storage */
 537                 if (lws_ensure_user_space(wsi))
 538                         goto bail_nuke_ah;
 539
 540                 /*
 541                  * Give the user code a chance to study the request and
 542                  * have the opportunity to deny it
 543                  */
 544
 545                 if ((wsi->protocol->callback)(wsi,
 546                                 LWS_CALLBACK_FILTER_PROTOCOL_CONNECTION,
 547                                 wsi->user_space,
 548                               lws_hdr_simple_ptr(wsi, WSI_TOKEN_PROTOCOL), 0)) {
 549                         lwsl_warn("User code denied connection\n");
 550                         goto bail_nuke_ah;
 551                 }
 552
 553                 /*
 554                  * Perform the handshake according to the protocol version the
 555                  * client announced
 556                  */
 557
 558                 switch (wsi->ietf_spec_revision) {
 559                 case 13:
 560                         lwsl_parser("lws_parse calling handshake_04\n");
 561                         if (handshake_0405(context, wsi)) {
 562                                 lwsl_info("hs0405 has failed the connection\n");
 563                                 goto bail_nuke_ah;
 564                         }
 565                         break;
 566
 567                 default:
 568                         lwsl_warn("Unknown client spec version %d\n",
 569                                   wsi->ietf_spec_revision);
 570                         goto bail_nuke_ah;
 571                 }
 572
 573                 /* we are upgrading to ws, so http/1.1 and keepalive +
 574                  * pipelined header considerations about keeping the ah around
 575                  * no longer apply.  However it's common for the first ws
 576                  * protocol data to have been coalesced with the browser
 577                  * upgrade request and to already be in the ah rx buffer.
 578                  */
 579
 580                 lwsl_info("%s: %p: inheriting ah in ws mode (rxpos:%d, rxlen:%d)\n",
 581                           __func__, wsi, wsi->u.hdr.ah->rxpos,
 582                           wsi->u.hdr.ah->rxlen);
 583                 lws_pt_lock(pt);
 584                 hdr = wsi->u.hdr;
 585
 586                 lws_union_transition(wsi, LWSCM_WS_SERVING);
 587                 /*
 588                  * first service is WS mode will notice this, use the RX and
 589                  * then detach the ah (caution: we are not in u.hdr union
 590                  * mode any more then... ah_temp member is at start the same
 591                  * though)
 592                  *
 593                  * Because rxpos/rxlen shows something in the ah, we will get
 594                  * service guaranteed next time around the event loop
 595                  *
 596                  * All union members begin with hdr, so we can use it even
 597                  * though we transitioned to ws union mode (the ah detach
 598                  * code uses it anyway).
 599                  */
 600                 wsi->u.hdr = hdr;
 601                 lws_pt_unlock(pt);
 602
 603                 /*
 604                  * create the frame buffer for this connection according to the
 605                  * size mentioned in the protocol definition.  If 0 there, use
 606                  * a big default for compatibility
 607                  */
 608
 609                 n = wsi->protocol->rx_buffer_size;
 610                 if (!n)
 611                         n = LWS_MAX_SOCKET_IO_BUF;
 612                 n += LWS_PRE;
 613                 wsi->u.ws.rx_ubuf = lws_malloc(n + 4 /* 0x0000ffff zlib */);
 614                 if (!wsi->u.ws.rx_ubuf) {
 615                         lwsl_err("Out of Mem allocating rx buffer %d\n", n);
 616                         return 1;
 617                 }
 618                 wsi->u.ws.rx_ubuf_alloc = n;
 619                 lwsl_info("Allocating RX buffer %d\n", n);
 620 #if LWS_POSIX
 621                 if (setsockopt(wsi->sock, SOL_SOCKET, SO_SNDBUF,
 622                                (const char *)&n, sizeof n)) {
 623                         lwsl_warn("Failed to set SNDBUF to %d", n);
 624                         return 1;
 625                 }
 626 #endif
 627                 lwsl_parser("accepted v%02d connection\n", wsi->ietf_spec_revision);
 628
 629                 return 0;
 630         } /* while all chars are handled */
 631
 632         return 0;
 633
 634 bail_nuke_ah:
 635         /* drop the header info */
 636         /* we're closing, losing some rx is OK */
 637         wsi->u.hdr.ah->rxpos = wsi->u.hdr.ah->rxlen;
 638         lws_header_table_detach(wsi);
 639
 640         return 1;
 641 }
 642
 643 static int
 644 lws_get_idlest_tsi(struct lws_context *context)
 645 {
 646         unsigned int lowest = ~0;
 647         int n = 0, hit = -1;
 648
 649         for (; n < context->count_threads; n++) {
 650                 if ((unsigned int)context->pt[n].fds_count != context->fd_limit_per_thread - 1 &&
 651                     (unsigned int)context->pt[n].fds_count < lowest) {
 652                         lowest = context->pt[n].fds_count;
 653                         hit = n;
 654                 }
 655         }
 656
 657         return hit;
 658 }
 659
 660 struct lws *
 661 lws_create_new_server_wsi(struct lws_context *context)
 662 {
 663         struct lws *new_wsi;
 664         int n = lws_get_idlest_tsi(context);
 665
 666         if (n < 0) {
 667                 lwsl_err("no space for new conn\n");
 668                 return NULL;
 669         }
 670
 671         new_wsi = lws_zalloc(sizeof(struct lws));
 672         if (new_wsi == NULL) {
 673                 lwsl_err("Out of memory for new connection\n");
 674                 return NULL;
 675         }
 676
 677         new_wsi->tsi = n;
 678         lwsl_info("Accepted %p to tsi %d\n", new_wsi, new_wsi->tsi);
 679
 680         new_wsi->context = context;
 681         new_wsi->pending_timeout = NO_PENDING_TIMEOUT;
 682         new_wsi->rxflow_change_to = LWS_RXFLOW_ALLOW;
 683
 684         /* intialize the instance struct */
 685
 686         new_wsi->state = LWSS_HTTP;
 687         new_wsi->mode = LWSCM_HTTP_SERVING;
 688         new_wsi->hdr_parsing_completed = 0;
 689
 690 #ifdef LWS_OPENSSL_SUPPORT
 691         new_wsi->use_ssl = LWS_SSL_ENABLED(context);
 692 #endif
 693
 694         /*
 695          * these can only be set once the protocol is known
 696          * we set an unestablished connection's protocol pointer
 697          * to the start of the supported list, so it can look
 698          * for matching ones during the handshake
 699          */
 700         new_wsi->protocol = context->protocols;
 701         new_wsi->user_space = NULL;
 702         new_wsi->ietf_spec_revision = 0;
 703         new_wsi->sock = LWS_SOCK_INVALID;
 704         context->count_wsi_allocated++;
 705
 706         /*
 707          * outermost create notification for wsi
 708          * no user_space because no protocol selection
 709          */
 710         context->protocols[0].callback(new_wsi, LWS_CALLBACK_WSI_CREATE,
 711                                        NULL, NULL, 0);
 712
 713         return new_wsi;
 714 }
 715
 716 /**
 717  * lws_http_transaction_completed() - wait for new http transaction or close
 718  * @wsi:        websocket connection
 719  *
 720  *      Returns 1 if the HTTP connection must close now
 721  *      Returns 0 and resets connection to wait for new HTTP header /
 722  *        transaction if possible
 723  */
 724
 725 LWS_VISIBLE int LWS_WARN_UNUSED_RESULT
 726 lws_http_transaction_completed(struct lws *wsi)
 727 {
 728         lwsl_debug("%s: wsi %p\n", __func__, wsi);
 729         /* if we can't go back to accept new headers, drop the connection */
 730         if (wsi->u.http.connection_type != HTTP_CONNECTION_KEEP_ALIVE) {
 731                 lwsl_info("%s: %p: close connection\n", __func__, wsi);
 732                 return 1;
 733         }
 734
 735         /* otherwise set ourselves up ready to go again */
 736         wsi->state = LWSS_HTTP;
 737         wsi->mode = LWSCM_HTTP_SERVING;
 738         wsi->u.http.content_length = 0;
 739         wsi->hdr_parsing_completed = 0;
 740
 741         /* He asked for it to stay alive indefinitely */
 742         lws_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
 743
 744         /*
 745          * We already know we are on http1.1 / keepalive and the next thing
 746          * coming will be another header set.
 747          *
 748          * If there is no pending rx and we still have the ah, drop it and
 749          * reacquire a new ah when the new headers start to arrive.  (Otherwise
 750          * we needlessly hog an ah indefinitely.)
 751          *
 752          * However if there is pending rx and we know from the keepalive state
 753          * that is already at least the start of another header set, simply
 754          * reset the existing header table and keep it.
 755          */
 756         if (wsi->u.hdr.ah) {
 757                 lwsl_info("%s: wsi->more_rx_waiting=%d\n", __func__,
 758                                 wsi->more_rx_waiting);
 759
 760                 if (!wsi->more_rx_waiting) {
 761                         wsi->u.hdr.ah->rxpos = wsi->u.hdr.ah->rxlen;
 762                         lws_header_table_detach(wsi);
 763                 } else
 764                         lws_header_table_reset(wsi);
 765         }
 766
 767         /* If we're (re)starting on headers, need other implied init */
 768         wsi->u.hdr.ues = URIES_IDLE;
 769
 770         lwsl_info("%s: %p: keep-alive await new transaction\n", __func__, wsi);
 771
 772         return 0;
 773 }
 774
 775 /**
 776  * lws_adopt_socket() - adopt foreign socket as if listen socket accepted it
 777  * @context: lws context
 778  * @accept_fd: fd of already-accepted socket to adopt
 779  *
 780  * Either returns new wsi bound to accept_fd, or closes accept_fd and
 781  * returns NULL, having cleaned up any new wsi pieces.
 782  *
 783  * LWS adopts the socket in http serving mode, it's ready to accept an upgrade
 784  * to ws or just serve http.
 785  */
 786
 787 LWS_VISIBLE struct lws *
 788 lws_adopt_socket(struct lws_context *context, lws_sockfd_type accept_fd)
 789 {
 790         struct lws *new_wsi = lws_create_new_server_wsi(context);
 791
 792         if (!new_wsi) {
 793                 compatible_close(accept_fd);
 794                 return NULL;
 795         }
 796
 797         lwsl_debug("%s: new wsi %p\n", __func__, new_wsi);
 798
 799         new_wsi->sock = accept_fd;
 800
 801         /* the transport is accepted... give him time to negotiate */
 802         lws_set_timeout(new_wsi, PENDING_TIMEOUT_ESTABLISH_WITH_SERVER,
 803                         context->timeout_secs);
 804
 805 #if LWS_POSIX == 0
 806         mbed3_tcp_stream_accept(accept_fd, new_wsi);
 807 #endif
 808
 809         /*
 810          * A new connection was accepted. Give the user a chance to
 811          * set properties of the newly created wsi. There's no protocol
 812          * selected yet so we issue this to protocols[0]
 813          */
 814         if ((context->protocols[0].callback)(new_wsi,
 815              LWS_CALLBACK_SERVER_NEW_CLIENT_INSTANTIATED, NULL, NULL, 0)) {
 816                 compatible_close(new_wsi->sock);
 817                 lws_free(new_wsi);
 818                 return NULL;
 819         }
 820
 821         lws_libev_accept(new_wsi, new_wsi->sock);
 822         lws_libuv_accept(new_wsi, new_wsi->sock);
 823
 824         if (!LWS_SSL_ENABLED(context)) {
 825                 if (insert_wsi_socket_into_fds(context, new_wsi))
 826                         goto fail;
 827         } else {
 828                 new_wsi->mode = LWSCM_SSL_INIT;
 829                 if (lws_server_socket_service_ssl(new_wsi, accept_fd))
 830                         goto fail;
 831         }
 832
 833         return new_wsi;
 834
 835 fail:
 836         lwsl_err("%s: fail\n", __func__);
 837         lws_close_free_wsi(new_wsi, LWS_CLOSE_STATUS_NOSTATUS);
 838
 839         return NULL;
 840 }
 841
 842 LWS_VISIBLE int
 843 lws_server_socket_service(struct lws_context *context, struct lws *wsi,
 844                           struct lws_pollfd *pollfd)
 845 {
 846         struct lws_context_per_thread *pt = &context->pt[(int)wsi->tsi];
 847         lws_sockfd_type accept_fd = LWS_SOCK_INVALID;
 848         struct allocated_headers *ah;
 849 #if LWS_POSIX
 850         struct sockaddr_in cli_addr;
 851         socklen_t clilen;
 852 #endif
 853         int n, len;
 854
 855         switch (wsi->mode) {
 856
 857         case LWSCM_HTTP_SERVING:
 858         case LWSCM_HTTP_SERVING_ACCEPTED:
 859         case LWSCM_HTTP2_SERVING:
 860
 861                 /* handle http headers coming in */
 862
 863                 /* pending truncated sends have uber priority */
 864
 865                 if (wsi->trunc_len) {
 866                         if (!(pollfd->revents & LWS_POLLOUT))
 867                                 break;
 868
 869                         if (lws_issue_raw(wsi, wsi->trunc_alloc +
 870                                                wsi->trunc_offset,
 871                                           wsi->trunc_len) < 0)
 872                                 goto fail;
 873                         /*
 874                          * we can't afford to allow input processing to send
 875                          * something new, so spin around he event loop until
 876                          * he doesn't have any partials
 877                          */
 878                         break;
 879                 }
 880
 881                 /* any incoming data ready? */
 882
 883                 if (!(pollfd->revents & pollfd->events & LWS_POLLIN))
 884                         goto try_pollout;
 885
 886                 /* these states imply we MUST have an ah attached */
 887
 888                 if (wsi->state == LWSS_HTTP ||
 889                     wsi->state == LWSS_HTTP_ISSUING_FILE ||
 890                     wsi->state == LWSS_HTTP_HEADERS) {
 891                         if (!wsi->u.hdr.ah)
 892                                 if (lws_header_table_attach(wsi))
 893                                         goto try_pollout;
 894
 895                         ah = wsi->u.hdr.ah;
 896
 897                         lwsl_debug("%s: %p: rxpos:%d rxlen:%d\n", __func__, wsi,
 898                                    ah->rxpos, ah->rxlen);
 899
 900                         /* if nothing in ah rx buffer, get some fresh rx */
 901                         if (ah->rxpos == ah->rxlen) {
 902                                 ah->rxlen = lws_ssl_capable_read(wsi, ah->rx,
 903                                                    sizeof(ah->rx));
 904                                 ah->rxpos = 0;
 905                                 lwsl_debug("%s: wsi %p, ah->rxlen = %d\r\n",
 906                                            __func__, wsi, ah->rxlen);
 907                                 switch (ah->rxlen) {
 908                                 case 0:
 909                                         lwsl_info("%s: read 0 len\n", __func__);
 910                                         /* lwsl_info("   state=%d\n", wsi->state); */
 911 //                                      if (!wsi->hdr_parsing_completed)
 912 //                                              lws_header_table_detach(wsi);
 913                                         /* fallthru */
 914                                 case LWS_SSL_CAPABLE_ERROR:
 915                                         goto fail;
 916                                 case LWS_SSL_CAPABLE_MORE_SERVICE:
 917                                         ah->rxlen = ah->rxpos = 0;
 918                                         goto try_pollout;
 919                                 }
 920                         }
 921                         assert(ah->rxpos != ah->rxlen && ah->rxlen);
 922                         /* just ignore incoming if waiting for close */
 923                         if (wsi->state != LWSS_FLUSHING_STORED_SEND_BEFORE_CLOSE) {
 924                                 n = lws_read(wsi, ah->rx + ah->rxpos,
 925                                              ah->rxlen - ah->rxpos);
 926                                 if (n < 0) /* we closed wsi */
 927                                         return 1;
 928                                 if (wsi->u.hdr.ah) {
 929                                         if ( wsi->u.hdr.ah->rxlen)
 930                                                  wsi->u.hdr.ah->rxpos += n;
 931
 932                                         if (wsi->u.hdr.ah->rxpos == wsi->u.hdr.ah->rxlen &&
 933                                             (wsi->mode != LWSCM_HTTP_SERVING &&
 934                                              wsi->mode != LWSCM_HTTP_SERVING_ACCEPTED &&
 935                                              wsi->mode != LWSCM_HTTP2_SERVING))
 936                                                 lws_header_table_detach(wsi);
 937                                 }
 938                                 break;
 939                         }
 940
 941                         goto try_pollout;
 942                 }
 943
 944                 len = lws_ssl_capable_read(wsi, pt->serv_buf,
 945                                            LWS_MAX_SOCKET_IO_BUF);
 946                 lwsl_debug("%s: wsi %p read %d\r\n", __func__, wsi, len);
 947                 switch (len) {
 948                 case 0:
 949                         lwsl_info("%s: read 0 len\n", __func__);
 950                         /* lwsl_info("   state=%d\n", wsi->state); */
 951 //                      if (!wsi->hdr_parsing_completed)
 952 //                              lws_header_table_detach(wsi);
 953                         /* fallthru */
 954                 case LWS_SSL_CAPABLE_ERROR:
 955                         goto fail;
 956                 case LWS_SSL_CAPABLE_MORE_SERVICE:
 957                         goto try_pollout;
 958                 }
 959
 960                 /* just ignore incoming if waiting for close */
 961                 if (wsi->state != LWSS_FLUSHING_STORED_SEND_BEFORE_CLOSE) {
 962                         /*
 963                          * hm this may want to send
 964                          * (via HTTP callback for example)
 965                          */
 966                         n = lws_read(wsi, pt->serv_buf, len);
 967                         if (n < 0) /* we closed wsi */
 968                                 return 1;
 969                         /* hum he may have used up the
 970                          * writability above */
 971                         break;
 972                 }
 973
 974 try_pollout:
 975                 /* this handles POLLOUT for http serving fragments */
 976
 977                 if (!(pollfd->revents & LWS_POLLOUT))
 978                         break;
 979
 980                 /* one shot */
 981                 if (lws_change_pollfd(wsi, LWS_POLLOUT, 0)) {
 982                         lwsl_notice("%s a\n", __func__);
 983                         goto fail;
 984                 }
 985
 986                 if (wsi->state != LWSS_HTTP_ISSUING_FILE) {
 987                         n = user_callback_handle_rxflow(wsi->protocol->callback,
 988                                         wsi, LWS_CALLBACK_HTTP_WRITEABLE,
 989                                         wsi->user_space, NULL, 0);
 990                         if (n < 0) {
 991                                 lwsl_info("writeable_fail\n");
 992                                 goto fail;
 993                         }
 994                         break;
 995                 }
 996
 997                 /* >0 == completion, <0 == error */
 998                 n = lws_serve_http_file_fragment(wsi);
 999                 if (n < 0 || (n > 0 && lws_http_transaction_completed(wsi))) {
1000                         lwsl_info("completed\n");
1001                         goto fail;
1002                 }
1003                 break;
1004
1005         case LWSCM_SERVER_LISTENER:
1006
1007 #if LWS_POSIX
1008                 /* pollin means a client has connected to us then */
1009
1010                 do {
1011                         if (!(pollfd->revents & LWS_POLLIN) || !(pollfd->events & LWS_POLLIN))
1012                                 break;
1013
1014                         /* listen socket got an unencrypted connection... */
1015
1016                         clilen = sizeof(cli_addr);
1017                         lws_latency_pre(context, wsi);
1018                         accept_fd  = accept(pollfd->fd, (struct sockaddr *)&cli_addr,
1019                                             &clilen);
1020                         lws_latency(context, wsi, "listener accept", accept_fd,
1021                                     accept_fd >= 0);
1022                         if (accept_fd < 0) {
1023                                 if (LWS_ERRNO == LWS_EAGAIN ||
1024                                     LWS_ERRNO == LWS_EWOULDBLOCK) {
1025                                         lwsl_err("accept asks to try again\n");
1026                                         break;
1027                                 }
1028                                 lwsl_err("ERROR on accept: %s\n", strerror(LWS_ERRNO));
1029                                 break;
1030                         }
1031
1032                         lws_plat_set_socket_options(context, accept_fd);
1033
1034                         lwsl_debug("accepted new conn  port %u on fd=%d\n",
1035                                           ntohs(cli_addr.sin_port), accept_fd);
1036
1037 #else
1038                         /* not very beautiful... */
1039                         accept_fd = (lws_sockfd_type)pollfd;
1040 #endif
1041                         /*
1042                          * look at who we connected to and give user code a chance
1043                          * to reject based on client IP.  There's no protocol selected
1044                          * yet so we issue this to protocols[0]
1045                          */
1046                         if ((context->protocols[0].callback)(wsi,
1047                                         LWS_CALLBACK_FILTER_NETWORK_CONNECTION,
1048                                         NULL, (void *)(long)accept_fd, 0)) {
1049                                 lwsl_debug("Callback denied network connection\n");
1050                                 compatible_close(accept_fd);
1051                                 break;
1052                         }
1053
1054                         if (!lws_adopt_socket(context, accept_fd))
1055                                 /* already closed cleanly as necessary */
1056                                 return 1;
1057
1058 #if LWS_POSIX
1059                 } while (pt->fds_count < context->fd_limit_per_thread - 1 &&
1060                          lws_poll_listen_fd(&pt->fds[wsi->position_in_fds_table]) > 0);
1061 #endif
1062                 return 0;
1063
1064         default:
1065                 break;
1066         }
1067
1068         if (!lws_server_socket_service_ssl(wsi, accept_fd))
1069                 return 0;
1070
1071 fail:
1072         lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS);
1073
1074         return 1;
1075 }
1076
1077 /**
1078  * lws_serve_http_file() - Send a file back to the client using http
1079  * @wsi:                Websocket instance (available from user callback)
1080  * @file:               The file to issue over http
1081  * @content_type:       The http content type, eg, text/html
1082  * @other_headers:      NULL or pointer to header string
1083  * @other_headers_len:  length of the other headers if non-NULL
1084  *
1085  *      This function is intended to be called from the callback in response
1086  *      to http requests from the client.  It allows the callback to issue
1087  *      local files down the http link in a single step.
1088  *
1089  *      Returning <0 indicates error and the wsi should be closed.  Returning
1090  *      >0 indicates the file was completely sent and
1091  *      lws_http_transaction_completed() called on the wsi (and close if != 0)
1092  *      ==0 indicates the file transfer is started and needs more service later,
1093  *      the wsi should be left alone.
1094  */
1095
1096 LWS_VISIBLE int
1097 lws_serve_http_file(struct lws *wsi, const char *file, const char *content_type,
1098                     const char *other_headers, int other_headers_len)
1099 {
1100         struct lws_context *context = lws_get_context(wsi);
1101         struct lws_context_per_thread *pt = &context->pt[(int)wsi->tsi];
1102         unsigned char *response = pt->serv_buf + LWS_PRE;
1103         unsigned char *p = response;
1104         unsigned char *end = p + LWS_MAX_SOCKET_IO_BUF - LWS_PRE;
1105         int ret = 0;
1106
1107         wsi->u.http.fd = lws_plat_file_open(wsi, file, &wsi->u.http.filelen,
1108                                             O_RDONLY);
1109
1110         if (wsi->u.http.fd == LWS_INVALID_FILE) {
1111                 lwsl_err("Unable to open '%s'\n", file);
1112                 lws_return_http_status(wsi, HTTP_STATUS_NOT_FOUND, NULL);
1113
1114                 return -1;
1115         }
1116
1117         if (lws_add_http_header_status(wsi, 200, &p, end))
1118                 return -1;
1119         if (lws_add_http_header_by_token(wsi, WSI_TOKEN_HTTP_SERVER,
1120                                          (unsigned char *)"libwebsockets", 13,
1121                                          &p, end))
1122                 return -1;
1123         if (lws_add_http_header_by_token(wsi, WSI_TOKEN_HTTP_CONTENT_TYPE,
1124                                          (unsigned char *)content_type,
1125                                          strlen(content_type), &p, end))
1126                 return -1;
1127         if (lws_add_http_header_content_length(wsi, wsi->u.http.filelen, &p, end))
1128                 return -1;
1129
1130         if (other_headers) {
1131                 if ((end - p) < other_headers_len)
1132                         return -1;
1133                 memcpy(p, other_headers, other_headers_len);
1134                 p += other_headers_len;
1135         }
1136
1137         if (lws_finalize_http_header(wsi, &p, end))
1138                 return -1;
1139
1140         ret = lws_write(wsi, response, p - response, LWS_WRITE_HTTP_HEADERS);
1141         if (ret != (p - response)) {
1142                 lwsl_err("_write returned %d from %d\n", ret, (p - response));
1143                 return -1;
1144         }
1145
1146         wsi->u.http.filepos = 0;
1147         wsi->state = LWSS_HTTP_ISSUING_FILE;
1148
1149         return lws_serve_http_file_fragment(wsi);
1150 }
1151
1152 int
1153 lws_interpret_incoming_packet(struct lws *wsi, unsigned char **buf, size_t len)
1154 {
1155         int m;
1156
1157         lwsl_parser("%s: received %d byte packet\n", __func__, (int)len);
1158 #if 0
1159         lwsl_hexdump(*buf, len);
1160 #endif
1161
1162         /* let the rx protocol state machine have as much as it needs */
1163
1164         while (len) {
1165                 /*
1166                  * we were accepting input but now we stopped doing so
1167                  */
1168                 if (!(wsi->rxflow_change_to & LWS_RXFLOW_ALLOW)) {
1169                         lws_rxflow_cache(wsi, *buf, 0, len);
1170                         lwsl_parser("%s: cached %d\n", __func__, len);
1171                         return 1;
1172                 }
1173
1174                 if (wsi->u.ws.rx_draining_ext) {
1175                         m = lws_rx_sm(wsi, 0);
1176                         if (m < 0)
1177                                 return -1;
1178                         continue;
1179                 }
1180
1181                 /* account for what we're using in rxflow buffer */
1182                 if (wsi->rxflow_buffer)
1183                         wsi->rxflow_pos++;
1184
1185                 /* consume payload bytes efficiently */
1186                 if (wsi->lws_rx_parse_state ==
1187                     LWS_RXPS_PAYLOAD_UNTIL_LENGTH_EXHAUSTED)
1188                         lws_payload_until_length_exhausted(wsi, buf, &len);
1189
1190                 /* process the byte */
1191                 m = lws_rx_sm(wsi, *(*buf)++);
1192                 if (m < 0)
1193                         return -1;
1194                 len--;
1195         }
1196
1197         lwsl_parser("%s: exit with %d unused\n", __func__, (int)len);
1198
1199         return 0;
1200 }
1201
1202 LWS_VISIBLE void
1203 lws_server_get_canonical_hostname(struct lws_context *context,
1204                                   struct lws_context_creation_info *info)
1205 {
1206         if (info->options & LWS_SERVER_OPTION_SKIP_SERVER_CANONICAL_NAME)
1207                 return;
1208 #if LWS_POSIX
1209         /* find canonical hostname */
1210         gethostname((char *)context->canonical_hostname,
1211                     sizeof(context->canonical_hostname) - 1);
1212
1213         lwsl_notice(" canonical_hostname = %s\n", context->canonical_hostname);
1214 #else
1215         (void)context;
1216 #endif
1217 }