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                         wsi->context->timeout_secs);
 306
 307         n = wsi->protocol->callback(wsi, LWS_CALLBACK_HTTP,
 308                                     wsi->user_space, uri_ptr, uri_len);
 309         if (n) {
 310                 lwsl_info("LWS_CALLBACK_HTTP closing\n");
 311
 312                 return 1;
 313         }
 314
 315         /*
 316          * If we're not issuing a file, check for content_length or
 317          * HTTP keep-alive. No keep-alive header allocation for
 318          * ISSUING_FILE, as this uses HTTP/1.0.
 319          *
 320          * In any case, return 0 and let lws_read decide how to
 321          * proceed based on state
 322          */
 323         if (wsi->state != LWSS_HTTP_ISSUING_FILE)
 324                 /* Prepare to read body if we have a content length: */
 325                 if (wsi->u.http.content_length > 0)
 326                         wsi->state = LWSS_HTTP_BODY;
 327
 328         return 0;
 329
 330 bail_nuke_ah:
 331         /* we're closing, losing some rx is OK */
 332         wsi->u.hdr.ah->rxpos = wsi->u.hdr.ah->rxlen;
 333         lws_header_table_detach(wsi);
 334
 335         return 1;
 336 }
 337
 338
 339 int
 340 lws_handshake_server(struct lws *wsi, unsigned char **buf, size_t len)
 341 {
 342         struct lws_context *context = lws_get_context(wsi);
 343         struct lws_context_per_thread *pt = &context->pt[(int)wsi->tsi];
 344         struct _lws_header_related hdr;
 345         struct allocated_headers *ah;
 346         int protocol_len, n, hit;
 347         char protocol_list[128];
 348         char protocol_name[32];
 349         char *p;
 350
 351         assert(len < 10000000);
 352         assert(wsi->u.hdr.ah);
 353
 354         while (len--) {
 355                 wsi->u.hdr.more_rx_waiting = !!len;
 356
 357                 assert(wsi->mode == LWSCM_HTTP_SERVING);
 358
 359                 if (lws_parse(wsi, *(*buf)++)) {
 360                         lwsl_info("lws_parse failed\n");
 361                         goto bail_nuke_ah;
 362                 }
 363
 364                 if (wsi->u.hdr.parser_state != WSI_PARSING_COMPLETE)
 365                         continue;
 366
 367                 lwsl_parser("lws_parse sees parsing complete\n");
 368
 369                 wsi->mode = LWSCM_PRE_WS_SERVING_ACCEPT;
 370                 lws_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
 371
 372                 /* is this websocket protocol or normal http 1.0? */
 373
 374                 if (lws_hdr_total_length(wsi, WSI_TOKEN_UPGRADE)) {
 375                         if (!strcasecmp(lws_hdr_simple_ptr(wsi, WSI_TOKEN_UPGRADE),
 376                                         "websocket")) {
 377                                 lwsl_info("Upgrade to ws\n");
 378                                 goto upgrade_ws;
 379                         }
 380 #ifdef LWS_USE_HTTP2
 381                         if (!strcasecmp(lws_hdr_simple_ptr(wsi, WSI_TOKEN_UPGRADE),
 382                                         "h2c-14")) {
 383                                 lwsl_info("Upgrade to h2c-14\n");
 384                                 goto upgrade_h2c;
 385                         }
 386 #endif
 387                         lwsl_err("Unknown upgrade\n");
 388                         /* dunno what he wanted to upgrade to */
 389                         goto bail_nuke_ah;
 390                 }
 391
 392                 /* no upgrade ack... he remained as HTTP */
 393
 394                 lwsl_info("No upgrade\n");
 395                 ah = wsi->u.hdr.ah;
 396
 397                 lws_union_transition(wsi, LWSCM_HTTP_SERVING_ACCEPTED);
 398                 wsi->state = LWSS_HTTP;
 399                 wsi->u.http.fd = LWS_INVALID_FILE;
 400
 401                 /* expose it at the same offset as u.hdr */
 402                 wsi->u.http.ah = ah;
 403                 lwsl_debug("%s: wsi %p: ah %p\n", __func__, (void *)wsi, (void *)wsi->u.hdr.ah);
 404
 405                 n = lws_http_action(wsi);
 406
 407                 return n;
 408
 409 #ifdef LWS_USE_HTTP2
 410 upgrade_h2c:
 411                 if (!lws_hdr_total_length(wsi, WSI_TOKEN_HTTP2_SETTINGS)) {
 412                         lwsl_err("missing http2_settings\n");
 413                         goto bail_nuke_ah;
 414                 }
 415
 416                 lwsl_err("h2c upgrade...\n");
 417
 418                 p = lws_hdr_simple_ptr(wsi, WSI_TOKEN_HTTP2_SETTINGS);
 419                 /* convert the peer's HTTP-Settings */
 420                 n = lws_b64_decode_string(p, protocol_list,
 421                                           sizeof(protocol_list));
 422                 if (n < 0) {
 423                         lwsl_parser("HTTP2_SETTINGS too long\n");
 424                         return 1;
 425                 }
 426
 427                 /* adopt the header info */
 428
 429                 ah = wsi->u.hdr.ah;
 430
 431                 lws_union_transition(wsi, LWSCM_HTTP2_SERVING);
 432
 433                 /* http2 union member has http union struct at start */
 434                 wsi->u.http.ah = ah;
 435
 436                 lws_http2_init(&wsi->u.http2.peer_settings);
 437                 lws_http2_init(&wsi->u.http2.my_settings);
 438
 439                 /* HTTP2 union */
 440
 441                 lws_http2_interpret_settings_payload(&wsi->u.http2.peer_settings,
 442                                 (unsigned char *)protocol_list, n);
 443
 444                 strcpy(protocol_list,
 445                        "HTTP/1.1 101 Switching Protocols\x0d\x0a"
 446                       "Connection: Upgrade\x0d\x0a"
 447                       "Upgrade: h2c\x0d\x0a\x0d\x0a");
 448                 n = lws_issue_raw(wsi, (unsigned char *)protocol_list,
 449                                         strlen(protocol_list));
 450                 if (n != strlen(protocol_list)) {
 451                         lwsl_debug("http2 switch: ERROR writing to socket\n");
 452                         return 1;
 453                 }
 454
 455                 wsi->state = LWSS_HTTP2_AWAIT_CLIENT_PREFACE;
 456
 457                 return 0;
 458 #endif
 459
 460 upgrade_ws:
 461                 if (!wsi->protocol)
 462                         lwsl_err("NULL protocol at lws_read\n");
 463
 464                 /*
 465                  * It's websocket
 466                  *
 467                  * Select the first protocol we support from the list
 468                  * the client sent us.
 469                  *
 470                  * Copy it to remove header fragmentation
 471                  */
 472
 473                 if (lws_hdr_copy(wsi, protocol_list, sizeof(protocol_list) - 1,
 474                                  WSI_TOKEN_PROTOCOL) < 0) {
 475                         lwsl_err("protocol list too long");
 476                         goto bail_nuke_ah;
 477                 }
 478
 479                 protocol_len = lws_hdr_total_length(wsi, WSI_TOKEN_PROTOCOL);
 480                 protocol_list[protocol_len] = '\0';
 481                 p = protocol_list;
 482                 hit = 0;
 483
 484                 while (*p && !hit) {
 485                         unsigned int n = 0;
 486                         while (n < sizeof(protocol_name) - 1 && *p && *p !=',')
 487                                 protocol_name[n++] = *p++;
 488                         protocol_name[n] = '\0';
 489                         if (*p)
 490                                 p++;
 491
 492                         lwsl_info("checking %s\n", protocol_name);
 493
 494                         n = 0;
 495                         while (context->protocols[n].callback) {
 496                                 if (context->protocols[n].name &&
 497                                     !strcmp(context->protocols[n].name,
 498                                             protocol_name)) {
 499                                         lwsl_info("prot match %d\n", n);
 500                                         wsi->protocol = &context->protocols[n];
 501                                         hit = 1;
 502                                         break;
 503                                 }
 504
 505                                 n++;
 506                         }
 507                 }
 508
 509                 /* we didn't find a protocol he wanted? */
 510
 511                 if (!hit) {
 512                         if (lws_hdr_simple_ptr(wsi, WSI_TOKEN_PROTOCOL)) {
 513                                 lwsl_err("No protocol from \"%s\" supported\n",
 514                                          protocol_list);
 515                                 goto bail_nuke_ah;
 516                         }
 517                         /*
 518                          * some clients only have one protocol and
 519                          * do not sent the protocol list header...
 520                          * allow it and match to protocol 0
 521                          */
 522                         lwsl_info("defaulting to prot 0 handler\n");
 523                         wsi->protocol = &context->protocols[0];
 524                 }
 525
 526                 /* allocate wsi->user storage */
 527                 if (lws_ensure_user_space(wsi))
 528                         goto bail_nuke_ah;
 529
 530                 /*
 531                  * Give the user code a chance to study the request and
 532                  * have the opportunity to deny it
 533                  */
 534
 535                 if ((wsi->protocol->callback)(wsi,
 536                                 LWS_CALLBACK_FILTER_PROTOCOL_CONNECTION,
 537                                 wsi->user_space,
 538                               lws_hdr_simple_ptr(wsi, WSI_TOKEN_PROTOCOL), 0)) {
 539                         lwsl_warn("User code denied connection\n");
 540                         goto bail_nuke_ah;
 541                 }
 542
 543                 /*
 544                  * Perform the handshake according to the protocol version the
 545                  * client announced
 546                  */
 547
 548                 switch (wsi->ietf_spec_revision) {
 549                 case 13:
 550                         lwsl_parser("lws_parse calling handshake_04\n");
 551                         if (handshake_0405(context, wsi)) {
 552                                 lwsl_info("hs0405 has failed the connection\n");
 553                                 goto bail_nuke_ah;
 554                         }
 555                         break;
 556
 557                 default:
 558                         lwsl_warn("Unknown client spec version %d\n",
 559                                   wsi->ietf_spec_revision);
 560                         goto bail_nuke_ah;
 561                 }
 562
 563                 /* we are upgrading to ws, so http/1.1 and keepalive +
 564                  * pipelined header considerations about keeping the ah around
 565                  * no longer apply.  However it's common for the first ws
 566                  * protocol data to have been coalesced with the browser
 567                  * upgrade request and to already be in the ah rx buffer.
 568                  */
 569
 570                 lwsl_info("%s: %p: inheriting ah in ws mode (rxpos:%d, rxlen:%d)\n",
 571                           __func__, wsi, wsi->u.hdr.ah->rxpos,
 572                           wsi->u.hdr.ah->rxlen);
 573                 lws_pt_lock(pt);
 574                 hdr = wsi->u.hdr;
 575
 576                 lws_union_transition(wsi, LWSCM_WS_SERVING);
 577                 /*
 578                  * first service is WS mode will notice this, use the RX and
 579                  * then detach the ah (caution: we are not in u.hdr union
 580                  * mode any more then... ah_temp member is at start the same
 581                  * though)
 582                  *
 583                  * Because rxpos/rxlen shows something in the ah, we will get
 584                  * service guaranteed next time around the event loop
 585                  *
 586                  * All union members begin with hdr, so we can use it even
 587                  * though we transitioned to ws union mode (the ah detach
 588                  * code uses it anyway).
 589                  */
 590                 wsi->u.hdr = hdr;
 591                 lws_pt_unlock(pt);
 592
 593                 /*
 594                  * create the frame buffer for this connection according to the
 595                  * size mentioned in the protocol definition.  If 0 there, use
 596                  * a big default for compatibility
 597                  */
 598
 599                 n = wsi->protocol->rx_buffer_size;
 600                 if (!n)
 601                         n = LWS_MAX_SOCKET_IO_BUF;
 602                 n += LWS_PRE;
 603                 wsi->u.ws.rx_ubuf = lws_malloc(n + 4 /* 0x0000ffff zlib */);
 604                 if (!wsi->u.ws.rx_ubuf) {
 605                         lwsl_err("Out of Mem allocating rx buffer %d\n", n);
 606                         return 1;
 607                 }
 608                 wsi->u.ws.rx_ubuf_alloc = n;
 609                 lwsl_info("Allocating RX buffer %d\n", n);
 610 #if LWS_POSIX
 611                 if (setsockopt(wsi->sock, SOL_SOCKET, SO_SNDBUF,
 612                                (const char *)&n, sizeof n)) {
 613                         lwsl_warn("Failed to set SNDBUF to %d", n);
 614                         return 1;
 615                 }
 616 #endif
 617                 lwsl_parser("accepted v%02d connection\n", wsi->ietf_spec_revision);
 618
 619                 return 0;
 620         } /* while all chars are handled */
 621
 622         return 0;
 623
 624 bail_nuke_ah:
 625         /* drop the header info */
 626         /* we're closing, losing some rx is OK */
 627         wsi->u.hdr.ah->rxpos = wsi->u.hdr.ah->rxlen;
 628         lws_header_table_detach(wsi);
 629
 630         return 1;
 631 }
 632
 633 static int
 634 lws_get_idlest_tsi(struct lws_context *context)
 635 {
 636         unsigned int lowest = ~0;
 637         int n = 0, hit = -1;
 638
 639         for (; n < context->count_threads; n++) {
 640                 if ((unsigned int)context->pt[n].fds_count != context->fd_limit_per_thread - 1 &&
 641                     (unsigned int)context->pt[n].fds_count < lowest) {
 642                         lowest = context->pt[n].fds_count;
 643                         hit = n;
 644                 }
 645         }
 646
 647         return hit;
 648 }
 649
 650 struct lws *
 651 lws_create_new_server_wsi(struct lws_context *context)
 652 {
 653         struct lws *new_wsi;
 654         int n = lws_get_idlest_tsi(context);
 655
 656         if (n < 0) {
 657                 lwsl_err("no space for new conn\n");
 658                 return NULL;
 659         }
 660
 661         new_wsi = lws_zalloc(sizeof(struct lws));
 662         if (new_wsi == NULL) {
 663                 lwsl_err("Out of memory for new connection\n");
 664                 return NULL;
 665         }
 666
 667         new_wsi->tsi = n;
 668         lwsl_info("Accepted %p to tsi %d\n", new_wsi, new_wsi->tsi);
 669
 670         new_wsi->context = context;
 671         new_wsi->pending_timeout = NO_PENDING_TIMEOUT;
 672         new_wsi->rxflow_change_to = LWS_RXFLOW_ALLOW;
 673
 674         /* intialize the instance struct */
 675
 676         new_wsi->state = LWSS_HTTP;
 677         new_wsi->mode = LWSCM_HTTP_SERVING;
 678         new_wsi->hdr_parsing_completed = 0;
 679
 680 #ifdef LWS_OPENSSL_SUPPORT
 681         new_wsi->use_ssl = LWS_SSL_ENABLED(context);
 682 #endif
 683
 684         /*
 685          * these can only be set once the protocol is known
 686          * we set an unestablished connection's protocol pointer
 687          * to the start of the supported list, so it can look
 688          * for matching ones during the handshake
 689          */
 690         new_wsi->protocol = context->protocols;
 691         new_wsi->user_space = NULL;
 692         new_wsi->ietf_spec_revision = 0;
 693         new_wsi->sock = LWS_SOCK_INVALID;
 694         context->count_wsi_allocated++;
 695
 696         /*
 697          * outermost create notification for wsi
 698          * no user_space because no protocol selection
 699          */
 700         context->protocols[0].callback(new_wsi, LWS_CALLBACK_WSI_CREATE,
 701                                        NULL, NULL, 0);
 702
 703         return new_wsi;
 704 }
 705
 706 /**
 707  * lws_http_transaction_completed() - wait for new http transaction or close
 708  * @wsi:        websocket connection
 709  *
 710  *      Returns 1 if the HTTP connection must close now
 711  *      Returns 0 and resets connection to wait for new HTTP header /
 712  *        transaction if possible
 713  */
 714
 715 LWS_VISIBLE int LWS_WARN_UNUSED_RESULT
 716 lws_http_transaction_completed(struct lws *wsi)
 717 {
 718         lwsl_debug("%s: wsi %p\n", __func__, wsi);
 719         /* if we can't go back to accept new headers, drop the connection */
 720         if (wsi->u.http.connection_type != HTTP_CONNECTION_KEEP_ALIVE) {
 721                 lwsl_info("%s: %p: close connection\n", __func__, wsi);
 722                 return 1;
 723         }
 724
 725         /* otherwise set ourselves up ready to go again */
 726         wsi->state = LWSS_HTTP;
 727         wsi->mode = LWSCM_HTTP_SERVING;
 728         wsi->u.http.content_length = 0;
 729         wsi->hdr_parsing_completed = 0;
 730
 731         /* He asked for it to stay alive indefinitely */
 732         lws_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
 733
 734         /*
 735          * We already know we are on http1.1 / keepalive and the next thing
 736          * coming will be another header set.
 737          *
 738          * If there is no pending rx and we still have the ah, drop it and
 739          * reacquire a new ah when the new headers start to arrive.  (Otherwise
 740          * we needlessly hog an ah indefinitely.)
 741          *
 742          * However if there is pending rx and we know from the keepalive state
 743          * that is already at least the start of another header set, simply
 744          * reset the existing header table and keep it.
 745          */
 746         if (wsi->u.hdr.ah) {
 747                 if (!wsi->u.hdr.more_rx_waiting) {
 748                         wsi->u.hdr.ah->rxpos = wsi->u.hdr.ah->rxlen;
 749                         lws_header_table_detach(wsi);
 750                 } else
 751                         lws_header_table_reset(wsi);
 752         }
 753
 754         /* If we're (re)starting on headers, need other implied init */
 755         wsi->u.hdr.ues = URIES_IDLE;
 756
 757         lwsl_info("%s: %p: keep-alive await new transaction\n", __func__, wsi);
 758
 759         return 0;
 760 }
 761
 762 /**
 763  * lws_adopt_socket() - adopt foreign socket as if listen socket accepted it
 764  * @context: lws context
 765  * @accept_fd: fd of already-accepted socket to adopt
 766  *
 767  * Either returns new wsi bound to accept_fd, or closes accept_fd and
 768  * returns NULL, having cleaned up any new wsi pieces.
 769  *
 770  * LWS adopts the socket in http serving mode, it's ready to accept an upgrade
 771  * to ws or just serve http.
 772  */
 773
 774 LWS_VISIBLE struct lws *
 775 lws_adopt_socket(struct lws_context *context, lws_sockfd_type accept_fd)
 776 {
 777         struct lws *new_wsi = lws_create_new_server_wsi(context);
 778
 779         if (!new_wsi) {
 780                 compatible_close(accept_fd);
 781                 return NULL;
 782         }
 783
 784         lwsl_debug("%s: new wsi %p\n", __func__, new_wsi);
 785
 786         new_wsi->sock = accept_fd;
 787
 788         /* the transport is accepted... give him time to negotiate */
 789         lws_set_timeout(new_wsi, PENDING_TIMEOUT_ESTABLISH_WITH_SERVER,
 790                         context->timeout_secs);
 791
 792 #if LWS_POSIX == 0
 793         mbed3_tcp_stream_accept(accept_fd, new_wsi);
 794 #endif
 795
 796         /*
 797          * A new connection was accepted. Give the user a chance to
 798          * set properties of the newly created wsi. There's no protocol
 799          * selected yet so we issue this to protocols[0]
 800          */
 801         if ((context->protocols[0].callback)(new_wsi,
 802              LWS_CALLBACK_SERVER_NEW_CLIENT_INSTANTIATED, NULL, NULL, 0)) {
 803                 compatible_close(new_wsi->sock);
 804                 lws_free(new_wsi);
 805                 return NULL;
 806         }
 807
 808         lws_libev_accept(new_wsi, new_wsi->sock);
 809         lws_libuv_accept(new_wsi, new_wsi->sock);
 810
 811         if (!LWS_SSL_ENABLED(context)) {
 812                 if (insert_wsi_socket_into_fds(context, new_wsi))
 813                         goto fail;
 814         } else {
 815                 new_wsi->mode = LWSCM_SSL_INIT;
 816                 if (lws_server_socket_service_ssl(new_wsi, accept_fd))
 817                         goto fail;
 818         }
 819
 820         return new_wsi;
 821
 822 fail:
 823         lwsl_err("%s: fail\n", __func__);
 824         lws_close_free_wsi(new_wsi, LWS_CLOSE_STATUS_NOSTATUS);
 825
 826         return NULL;
 827 }
 828
 829 LWS_VISIBLE int
 830 lws_server_socket_service(struct lws_context *context, struct lws *wsi,
 831                           struct lws_pollfd *pollfd)
 832 {
 833         struct lws_context_per_thread *pt = &context->pt[(int)wsi->tsi];
 834         lws_sockfd_type accept_fd = LWS_SOCK_INVALID;
 835         struct allocated_headers *ah;
 836 #if LWS_POSIX
 837         struct sockaddr_in cli_addr;
 838         socklen_t clilen;
 839 #endif
 840         int n, len;
 841
 842         switch (wsi->mode) {
 843
 844         case LWSCM_HTTP_SERVING:
 845         case LWSCM_HTTP_SERVING_ACCEPTED:
 846         case LWSCM_HTTP2_SERVING:
 847
 848                 /* handle http headers coming in */
 849
 850                 /* pending truncated sends have uber priority */
 851
 852                 if (wsi->trunc_len) {
 853                         if (!(pollfd->revents & LWS_POLLOUT))
 854                                 break;
 855
 856                         if (lws_issue_raw(wsi, wsi->trunc_alloc +
 857                                                wsi->trunc_offset,
 858                                           wsi->trunc_len) < 0)
 859                                 goto fail;
 860                         /*
 861                          * we can't afford to allow input processing to send
 862                          * something new, so spin around he event loop until
 863                          * he doesn't have any partials
 864                          */
 865                         break;
 866                 }
 867
 868                 /* any incoming data ready? */
 869
 870                 if (!(pollfd->revents & pollfd->events & LWS_POLLIN))
 871                         goto try_pollout;
 872
 873                 /* these states imply we MUST have an ah attached */
 874
 875                 if (wsi->state == LWSS_HTTP ||
 876                     wsi->state == LWSS_HTTP_ISSUING_FILE ||
 877                     wsi->state == LWSS_HTTP_HEADERS) {
 878                         if (!wsi->u.hdr.ah)
 879                                 if (lws_header_table_attach(wsi))
 880                                         goto try_pollout;
 881
 882                         ah = wsi->u.hdr.ah;
 883
 884                         lwsl_debug("%s: %p: rxpos:%d rxlen:%d\n", __func__, wsi,
 885                                    ah->rxpos, ah->rxlen);
 886
 887                         /* if nothing in ah rx buffer, get some fresh rx */
 888                         if (ah->rxpos == ah->rxlen) {
 889                                 ah->rxlen = lws_ssl_capable_read(wsi, ah->rx,
 890                                                    sizeof(ah->rx));
 891                                 ah->rxpos = 0;
 892                                 lwsl_debug("%s: wsi %p, ah->rxlen = %d\r\n",
 893                                            __func__, wsi, ah->rxlen);
 894                                 switch (ah->rxlen) {
 895                                 case 0:
 896                                         lwsl_info("%s: read 0 len\n", __func__);
 897                                         /* lwsl_info("   state=%d\n", wsi->state); */
 898 //                                      if (!wsi->hdr_parsing_completed)
 899 //                                              lws_header_table_detach(wsi);
 900                                         /* fallthru */
 901                                 case LWS_SSL_CAPABLE_ERROR:
 902                                         goto fail;
 903                                 case LWS_SSL_CAPABLE_MORE_SERVICE:
 904                                         ah->rxlen = ah->rxpos = 0;
 905                                         goto try_pollout;
 906                                 }
 907                         }
 908                         assert(ah->rxpos != ah->rxlen && ah->rxlen);
 909                         /* just ignore incoming if waiting for close */
 910                         if (wsi->state != LWSS_FLUSHING_STORED_SEND_BEFORE_CLOSE) {
 911                                 n = lws_read(wsi, ah->rx + ah->rxpos,
 912                                              ah->rxlen - ah->rxpos);
 913                                 if (n < 0) /* we closed wsi */
 914                                         return 1;
 915                                 if (wsi->u.hdr.ah) {
 916                                         if ( wsi->u.hdr.ah->rxlen)
 917                                                  wsi->u.hdr.ah->rxpos += n;
 918
 919                                         if (wsi->u.hdr.ah->rxpos == wsi->u.hdr.ah->rxlen &&
 920                                             (wsi->mode != LWSCM_HTTP_SERVING &&
 921                                              wsi->mode != LWSCM_HTTP_SERVING_ACCEPTED &&
 922                                              wsi->mode != LWSCM_HTTP2_SERVING))
 923                                                 lws_header_table_detach(wsi);
 924                                 }
 925                                 break;
 926                         }
 927
 928                         goto try_pollout;
 929                 }
 930
 931                 len = lws_ssl_capable_read(wsi, pt->serv_buf,
 932                                            LWS_MAX_SOCKET_IO_BUF);
 933                 lwsl_debug("%s: wsi %p read %d\r\n", __func__, wsi, len);
 934                 switch (len) {
 935                 case 0:
 936                         lwsl_info("%s: read 0 len\n", __func__);
 937                         /* lwsl_info("   state=%d\n", wsi->state); */
 938 //                      if (!wsi->hdr_parsing_completed)
 939 //                              lws_header_table_detach(wsi);
 940                         /* fallthru */
 941                 case LWS_SSL_CAPABLE_ERROR:
 942                         goto fail;
 943                 case LWS_SSL_CAPABLE_MORE_SERVICE:
 944                         goto try_pollout;
 945                 }
 946
 947                 /* just ignore incoming if waiting for close */
 948                 if (wsi->state != LWSS_FLUSHING_STORED_SEND_BEFORE_CLOSE) {
 949                         /*
 950                          * hm this may want to send
 951                          * (via HTTP callback for example)
 952                          */
 953                         n = lws_read(wsi, pt->serv_buf, len);
 954                         if (n < 0) /* we closed wsi */
 955                                 return 1;
 956                         /* hum he may have used up the
 957                          * writability above */
 958                         break;
 959                 }
 960
 961 try_pollout:
 962                 /* this handles POLLOUT for http serving fragments */
 963
 964                 if (!(pollfd->revents & LWS_POLLOUT))
 965                         break;
 966
 967                 /* one shot */
 968                 if (lws_change_pollfd(wsi, LWS_POLLOUT, 0)) {
 969                         lwsl_notice("%s a\n", __func__);
 970                         goto fail;
 971                 }
 972
 973                 if (wsi->state != LWSS_HTTP_ISSUING_FILE) {
 974                         n = user_callback_handle_rxflow(wsi->protocol->callback,
 975                                         wsi, LWS_CALLBACK_HTTP_WRITEABLE,
 976                                         wsi->user_space, NULL, 0);
 977                         if (n < 0) {
 978                                 lwsl_info("writeable_fail\n");
 979                                 goto fail;
 980                         }
 981                         break;
 982                 }
 983
 984                 /* >0 == completion, <0 == error */
 985                 n = lws_serve_http_file_fragment(wsi);
 986                 if (n < 0 || (n > 0 && lws_http_transaction_completed(wsi))) {
 987                         lwsl_info("completed\n");
 988                         goto fail;
 989                 }
 990                 break;
 991
 992         case LWSCM_SERVER_LISTENER:
 993
 994 #if LWS_POSIX
 995                 /* pollin means a client has connected to us then */
 996
 997                 do {
 998                         if (!(pollfd->revents & LWS_POLLIN) || !(pollfd->events & LWS_POLLIN))
 999                                 break;
1000
1001                         /* listen socket got an unencrypted connection... */
1002
1003                         clilen = sizeof(cli_addr);
1004                         lws_latency_pre(context, wsi);
1005                         accept_fd  = accept(pollfd->fd, (struct sockaddr *)&cli_addr,
1006                                             &clilen);
1007                         lws_latency(context, wsi, "listener accept", accept_fd,
1008                                     accept_fd >= 0);
1009                         if (accept_fd < 0) {
1010                                 if (LWS_ERRNO == LWS_EAGAIN ||
1011                                     LWS_ERRNO == LWS_EWOULDBLOCK) {
1012                                         lwsl_err("accept asks to try again\n");
1013                                         break;
1014                                 }
1015                                 lwsl_err("ERROR on accept: %s\n", strerror(LWS_ERRNO));
1016                                 break;
1017                         }
1018
1019                         lws_plat_set_socket_options(context, accept_fd);
1020
1021                         lwsl_debug("accepted new conn  port %u on fd=%d\n",
1022                                           ntohs(cli_addr.sin_port), accept_fd);
1023
1024 #else
1025                         /* not very beautiful... */
1026                         accept_fd = (lws_sockfd_type)pollfd;
1027 #endif
1028                         /*
1029                          * look at who we connected to and give user code a chance
1030                          * to reject based on client IP.  There's no protocol selected
1031                          * yet so we issue this to protocols[0]
1032                          */
1033                         if ((context->protocols[0].callback)(wsi,
1034                                         LWS_CALLBACK_FILTER_NETWORK_CONNECTION,
1035                                         NULL, (void *)(long)accept_fd, 0)) {
1036                                 lwsl_debug("Callback denied network connection\n");
1037                                 compatible_close(accept_fd);
1038                                 break;
1039                         }
1040
1041                         if (!lws_adopt_socket(context, accept_fd))
1042                                 /* already closed cleanly as necessary */
1043                                 return 1;
1044
1045 #if LWS_POSIX
1046                 } while (pt->fds_count < context->fd_limit_per_thread - 1 &&
1047                          lws_poll_listen_fd(&pt->fds[wsi->position_in_fds_table]) > 0);
1048 #endif
1049                 return 0;
1050
1051         default:
1052                 break;
1053         }
1054
1055         if (!lws_server_socket_service_ssl(wsi, accept_fd))
1056                 return 0;
1057
1058 fail:
1059         lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS);
1060
1061         return 1;
1062 }
1063
1064 /**
1065  * lws_serve_http_file() - Send a file back to the client using http
1066  * @wsi:                Websocket instance (available from user callback)
1067  * @file:               The file to issue over http
1068  * @content_type:       The http content type, eg, text/html
1069  * @other_headers:      NULL or pointer to header string
1070  * @other_headers_len:  length of the other headers if non-NULL
1071  *
1072  *      This function is intended to be called from the callback in response
1073  *      to http requests from the client.  It allows the callback to issue
1074  *      local files down the http link in a single step.
1075  *
1076  *      Returning <0 indicates error and the wsi should be closed.  Returning
1077  *      >0 indicates the file was completely sent and
1078  *      lws_http_transaction_completed() called on the wsi (and close if != 0)
1079  *      ==0 indicates the file transfer is started and needs more service later,
1080  *      the wsi should be left alone.
1081  */
1082
1083 LWS_VISIBLE int
1084 lws_serve_http_file(struct lws *wsi, const char *file, const char *content_type,
1085                     const char *other_headers, int other_headers_len)
1086 {
1087         struct lws_context *context = lws_get_context(wsi);
1088         struct lws_context_per_thread *pt = &context->pt[(int)wsi->tsi];
1089         unsigned char *response = pt->serv_buf + LWS_PRE;
1090         unsigned char *p = response;
1091         unsigned char *end = p + LWS_MAX_SOCKET_IO_BUF - LWS_PRE;
1092         int ret = 0;
1093
1094         wsi->u.http.fd = lws_plat_file_open(wsi, file, &wsi->u.http.filelen,
1095                                             O_RDONLY);
1096
1097         if (wsi->u.http.fd == LWS_INVALID_FILE) {
1098                 lwsl_err("Unable to open '%s'\n", file);
1099                 lws_return_http_status(wsi, HTTP_STATUS_NOT_FOUND, NULL);
1100
1101                 return -1;
1102         }
1103
1104         if (lws_add_http_header_status(wsi, 200, &p, end))
1105                 return -1;
1106         if (lws_add_http_header_by_token(wsi, WSI_TOKEN_HTTP_SERVER,
1107                                          (unsigned char *)"libwebsockets", 13,
1108                                          &p, end))
1109                 return -1;
1110         if (lws_add_http_header_by_token(wsi, WSI_TOKEN_HTTP_CONTENT_TYPE,
1111                                          (unsigned char *)content_type,
1112                                          strlen(content_type), &p, end))
1113                 return -1;
1114         if (lws_add_http_header_content_length(wsi, wsi->u.http.filelen, &p, end))
1115                 return -1;
1116
1117         if (other_headers) {
1118                 if ((end - p) < other_headers_len)
1119                         return -1;
1120                 memcpy(p, other_headers, other_headers_len);
1121                 p += other_headers_len;
1122         }
1123
1124         if (lws_finalize_http_header(wsi, &p, end))
1125                 return -1;
1126
1127         ret = lws_write(wsi, response, p - response, LWS_WRITE_HTTP_HEADERS);
1128         if (ret != (p - response)) {
1129                 lwsl_err("_write returned %d from %d\n", ret, (p - response));
1130                 return -1;
1131         }
1132
1133         wsi->u.http.filepos = 0;
1134         wsi->state = LWSS_HTTP_ISSUING_FILE;
1135
1136         return lws_serve_http_file_fragment(wsi);
1137 }
1138
1139 int
1140 lws_interpret_incoming_packet(struct lws *wsi, unsigned char **buf, size_t len)
1141 {
1142         int m;
1143
1144         lwsl_parser("%s: received %d byte packet\n", __func__, (int)len);
1145 #if 0
1146         lwsl_hexdump(*buf, len);
1147 #endif
1148
1149         /* let the rx protocol state machine have as much as it needs */
1150
1151         while (len) {
1152                 /*
1153                  * we were accepting input but now we stopped doing so
1154                  */
1155                 if (!(wsi->rxflow_change_to & LWS_RXFLOW_ALLOW)) {
1156                         lws_rxflow_cache(wsi, *buf, 0, len);
1157                         lwsl_parser("%s: cached %d\n", __func__, len);
1158                         return 1;
1159                 }
1160
1161                 if (wsi->u.ws.rx_draining_ext) {
1162                         m = lws_rx_sm(wsi, 0);
1163                         if (m < 0)
1164                                 return -1;
1165                         continue;
1166                 }
1167
1168                 /* account for what we're using in rxflow buffer */
1169                 if (wsi->rxflow_buffer)
1170                         wsi->rxflow_pos++;
1171
1172                 /* process the byte */
1173                 m = lws_rx_sm(wsi, *(*buf)++);
1174                 if (m < 0)
1175                         return -1;
1176                 len--;
1177         }
1178
1179         lwsl_parser("%s: exit with %d unused\n", __func__, (int)len);
1180
1181         return 0;
1182 }
1183
1184 LWS_VISIBLE void
1185 lws_server_get_canonical_hostname(struct lws_context *context,
1186                                   struct lws_context_creation_info *info)
1187 {
1188         if (info->options & LWS_SERVER_OPTION_SKIP_SERVER_CANONICAL_NAME)
1189                 return;
1190 #if LWS_POSIX
1191         /* find canonical hostname */
1192         gethostname((char *)context->canonical_hostname,
1193                     sizeof(context->canonical_hostname) - 1);
1194
1195         lwsl_notice(" canonical_hostname = %s\n", context->canonical_hostname);
1196 #else
1197         (void)context;
1198 #endif
1199 }