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