test-server/test-server-http.c

   1 /*
   2  * libwebsockets-test-server - libwebsockets test implementation
   3  *
   4  * Copyright (C) 2010-2016 Andy Green <andy@warmcat.com>
   5  *
   6  * This file is made available under the Creative Commons CC0 1.0
   7  * Universal Public Domain Dedication.
   8  *
   9  * The person who associated a work with this deed has dedicated
  10  * the work to the public domain by waiving all of his or her rights
  11  * to the work worldwide under copyright law, including all related
  12  * and neighboring rights, to the extent allowed by law. You can copy,
  13  * modify, distribute and perform the work, even for commercial purposes,
  14  * all without asking permission.
  15  *
  16  * The test apps are intended to be adapted for use in your code, which
  17  * may be proprietary.  So unlike the library itself, they are licensed
  18  * Public Domain.
  19  */
  20 #include "test-server.h"
  21
  22 /*
  23  * This demo server shows how to use libwebsockets for one or more
  24  * websocket protocols in the same server
  25  *
  26  * It defines the following websocket protocols:
  27  *
  28  *  dumb-increment-protocol:  once the socket is opened, an incrementing
  29  *                              ascii string is sent down it every 50ms.
  30  *                              If you send "reset\n" on the websocket, then
  31  *                              the incrementing number is reset to 0.
  32  *
  33  *  lws-mirror-protocol: copies any received packet to every connection also
  34  *                              using this protocol, including the sender
  35  */
  36
  37 extern int debug_level;
  38
  39 enum demo_protocols {
  40         /* always first */
  41         PROTOCOL_HTTP = 0,
  42
  43         PROTOCOL_DUMB_INCREMENT,
  44         PROTOCOL_LWS_MIRROR,
  45
  46         /* always last */
  47         DEMO_PROTOCOL_COUNT
  48 };
  49
  50 /*
  51  * We take a strict whitelist approach to stop ../ attacks
  52  */
  53 struct serveable {
  54         const char *urlpath;
  55         const char *mimetype;
  56 };
  57
  58 /*
  59  * this is just an example of parsing handshake headers, you don't need this
  60  * in your code unless you will filter allowing connections by the header
  61  * content
  62  */
  63 void
  64 dump_handshake_info(struct lws *wsi)
  65 {
  66         int n = 0, len;
  67         char buf[256];
  68         const unsigned char *c;
  69
  70         do {
  71                 c = lws_token_to_string(n);
  72                 if (!c) {
  73                         n++;
  74                         continue;
  75                 }
  76
  77                 len = lws_hdr_total_length(wsi, n);
  78                 if (!len || len > sizeof(buf) - 1) {
  79                         n++;
  80                         continue;
  81                 }
  82
  83                 lws_hdr_copy(wsi, buf, sizeof buf, n);
  84                 buf[sizeof(buf) - 1] = '\0';
  85
  86                 fprintf(stderr, "    %s = %s\n", (char *)c, buf);
  87                 n++;
  88         } while (c);
  89 }
  90
  91 const char * get_mimetype(const char *file)
  92 {
  93         int n = strlen(file);
  94
  95         if (n < 5)
  96                 return NULL;
  97
  98         if (!strcmp(&file[n - 4], ".ico"))
  99                 return "image/x-icon";
 100
 101         if (!strcmp(&file[n - 4], ".png"))
 102                 return "image/png";
 103
 104         if (!strcmp(&file[n - 5], ".html"))
 105                 return "text/html";
 106
 107         return NULL;
 108 }
 109
 110 /* this protocol server (always the first one) handles HTTP,
 111  *
 112  * Some misc callbacks that aren't associated with a protocol also turn up only
 113  * here on the first protocol server.
 114  */
 115
 116 int callback_http(struct lws *wsi, enum lws_callback_reasons reason, void *user,
 117                   void *in, size_t len)
 118 {
 119         struct per_session_data__http *pss =
 120                         (struct per_session_data__http *)user;
 121         unsigned char buffer[4096 + LWS_PRE];
 122         unsigned long amount, file_len, sent;
 123         char leaf_path[1024];
 124         const char *mimetype;
 125         char *other_headers;
 126         unsigned char *end;
 127         struct timeval tv;
 128         unsigned char *p;
 129         char buf[256];
 130         char b64[64];
 131         int n, m;
 132 #ifdef EXTERNAL_POLL
 133         struct lws_pollargs *pa = (struct lws_pollargs *)in;
 134 #endif
 135
 136         switch (reason) {
 137         case LWS_CALLBACK_HTTP:
 138
 139                 if (debug_level & LLL_INFO) {
 140                         dump_handshake_info(wsi);
 141
 142                         /* dump the individual URI Arg parameters */
 143                         n = 0;
 144                         while (lws_hdr_copy_fragment(wsi, buf, sizeof(buf),
 145                                                      WSI_TOKEN_HTTP_URI_ARGS, n) > 0) {
 146                                 lwsl_notice("URI Arg %d: %s\n", ++n, buf);
 147                         }
 148                 }
 149                 if (len < 1) {
 150                         lws_return_http_status(wsi,
 151                                                 HTTP_STATUS_BAD_REQUEST, NULL);
 152                         goto try_to_reuse;
 153                 }
 154
 155                 /* this example server has no concept of directories */
 156                 if (strchr((const char *)in + 1, '/')) {
 157                         lws_return_http_status(wsi, HTTP_STATUS_FORBIDDEN, NULL);
 158                         goto try_to_reuse;
 159                 }
 160
 161 #ifdef LWS_WITH_CGI
 162                 if (!strcmp(in, "/cgitest")) {
 163                         static char *cmd[] = {
 164                                 "/bin/sh",
 165                                 "-c",
 166                                 INSTALL_DATADIR"/libwebsockets-test-server/lws-cgi-test.sh",
 167                                 NULL
 168                         };
 169
 170                         lwsl_notice("%s: cgitest\n", __func__);
 171                         n = lws_cgi(wsi, cmd, 5);
 172                         if (n) {
 173                                 lwsl_err("%s: cgi failed\n");
 174                                 return -1;
 175                         }
 176                         p = buffer + LWS_PRE;
 177                         end = p + sizeof(buffer) - LWS_PRE;
 178
 179                         if (lws_add_http_header_status(wsi, 200, &p, end))
 180                                 return 1;
 181                         if (lws_add_http_header_by_token(wsi,
 182                                         WSI_TOKEN_HTTP_CONTENT_TYPE,
 183                                         (unsigned char *)"text/plain",
 184                                         10, &p, end))
 185                                 return 1;
 186                         if (lws_add_http_header_by_token(wsi, WSI_TOKEN_CONNECTION,
 187                                         (unsigned char *)"close", 5, &p, end))
 188                                 return 1;
 189                         if (lws_finalize_http_header(wsi, &p, end))
 190                                 return 1;
 191                         n = lws_write(wsi, buffer + LWS_PRE,
 192                                       p - (buffer + LWS_PRE),
 193                                       LWS_WRITE_HTTP_HEADERS);
 194                         break;
 195                 }
 196 #endif
 197
 198                 /* if a legal POST URL, let it continue and accept data */
 199                 if (lws_hdr_total_length(wsi, WSI_TOKEN_POST_URI))
 200                         return 0;
 201
 202                 /* check for the "send a big file by hand" example case */
 203
 204                 if (!strcmp((const char *)in, "/leaf.jpg")) {
 205                         if (strlen(resource_path) > sizeof(leaf_path) - 10)
 206                                 return -1;
 207                         sprintf(leaf_path, "%s/leaf.jpg", resource_path);
 208
 209                         /* well, let's demonstrate how to send the hard way */
 210
 211                         p = buffer + LWS_PRE;
 212                         end = p + sizeof(buffer) - LWS_PRE;
 213
 214                         pss->fd = lws_plat_file_open(wsi, leaf_path, &file_len,
 215                                                      LWS_O_RDONLY);
 216
 217                         if (pss->fd == LWS_INVALID_FILE) {
 218                                 lwsl_err("faild to open file %s\n", leaf_path);
 219                                 return -1;
 220                         }
 221
 222                         /*
 223                          * we will send a big jpeg file, but it could be
 224                          * anything.  Set the Content-Type: appropriately
 225                          * so the browser knows what to do with it.
 226                          *
 227                          * Notice we use the APIs to build the header, which
 228                          * will do the right thing for HTTP 1/1.1 and HTTP2
 229                          * depending on what connection it happens to be working
 230                          * on
 231                          */
 232                         if (lws_add_http_header_status(wsi, 200, &p, end))
 233                                 return 1;
 234                         if (lws_add_http_header_by_token(wsi, WSI_TOKEN_HTTP_SERVER,
 235                                         (unsigned char *)"libwebsockets",
 236                                         13, &p, end))
 237                                 return 1;
 238                         if (lws_add_http_header_by_token(wsi,
 239                                         WSI_TOKEN_HTTP_CONTENT_TYPE,
 240                                         (unsigned char *)"image/jpeg",
 241                                         10, &p, end))
 242                                 return 1;
 243                         if (lws_add_http_header_content_length(wsi,
 244                                                                file_len, &p,
 245                                                                end))
 246                                 return 1;
 247                         if (lws_finalize_http_header(wsi, &p, end))
 248                                 return 1;
 249
 250                         /*
 251                          * send the http headers...
 252                          * this won't block since it's the first payload sent
 253                          * on the connection since it was established
 254                          * (too small for partial)
 255                          *
 256                          * Notice they are sent using LWS_WRITE_HTTP_HEADERS
 257                          * which also means you can't send body too in one step,
 258                          * this is mandated by changes in HTTP2
 259                          */
 260
 261                         *p = '\0';
 262                         lwsl_info("%s\n", buffer + LWS_PRE);
 263
 264                         n = lws_write(wsi, buffer + LWS_PRE,
 265                                       p - (buffer + LWS_PRE),
 266                                       LWS_WRITE_HTTP_HEADERS);
 267                         if (n < 0) {
 268                                 lws_plat_file_close(wsi, pss->fd);
 269                                 return -1;
 270                         }
 271                         /*
 272                          * book us a LWS_CALLBACK_HTTP_WRITEABLE callback
 273                          */
 274                         lws_callback_on_writable(wsi);
 275                         break;
 276                 }
 277
 278                 /* if not, send a file the easy way */
 279                 strcpy(buf, resource_path);
 280                 if (strcmp(in, "/")) {
 281                         if (*((const char *)in) != '/')
 282                                 strcat(buf, "/");
 283                         strncat(buf, in, sizeof(buf) - strlen(resource_path));
 284                 } else /* default file to serve */
 285                         strcat(buf, "/test.html");
 286                 buf[sizeof(buf) - 1] = '\0';
 287
 288                 /* refuse to serve files we don't understand */
 289                 mimetype = get_mimetype(buf);
 290                 if (!mimetype) {
 291                         lwsl_err("Unknown mimetype for %s\n", buf);
 292                         lws_return_http_status(wsi,
 293                                       HTTP_STATUS_UNSUPPORTED_MEDIA_TYPE, NULL);
 294                         return -1;
 295                 }
 296
 297                 /* demonstrates how to set a cookie on / */
 298
 299                 other_headers = leaf_path;
 300                 p = (unsigned char *)leaf_path;
 301                 if (!strcmp((const char *)in, "/") &&
 302                            !lws_hdr_total_length(wsi, WSI_TOKEN_HTTP_COOKIE)) {
 303                         /* this isn't very unguessable but it'll do for us */
 304                         gettimeofday(&tv, NULL);
 305                         n = sprintf(b64, "test=LWS_%u_%u_COOKIE;Max-Age=360000",
 306                                 (unsigned int)tv.tv_sec,
 307                                 (unsigned int)tv.tv_usec);
 308
 309                         if (lws_add_http_header_by_name(wsi,
 310                                 (unsigned char *)"set-cookie:",
 311                                 (unsigned char *)b64, n, &p,
 312                                 (unsigned char *)leaf_path + sizeof(leaf_path)))
 313                                 return 1;
 314                 }
 315                 if (lws_is_ssl(wsi) && lws_add_http_header_by_name(wsi,
 316                                                 (unsigned char *)
 317                                                 "Strict-Transport-Security:",
 318                                                 (unsigned char *)
 319                                                 "max-age=15768000 ; "
 320                                                 "includeSubDomains", 36, &p,
 321                                                 (unsigned char *)leaf_path +
 322                                                         sizeof(leaf_path)))
 323                         return 1;
 324                 n = (char *)p - leaf_path;
 325
 326                 n = lws_serve_http_file(wsi, buf, mimetype, other_headers, n);
 327                 if (n < 0 || ((n > 0) && lws_http_transaction_completed(wsi)))
 328                         return -1; /* error or can't reuse connection: close the socket */
 329
 330                 /*
 331                  * notice that the sending of the file completes asynchronously,
 332                  * we'll get a LWS_CALLBACK_HTTP_FILE_COMPLETION callback when
 333                  * it's done
 334                  */
 335                 break;
 336
 337         case LWS_CALLBACK_HTTP_BODY:
 338                 strncpy(buf, in, 20);
 339                 buf[20] = '\0';
 340                 if (len < 20)
 341                         buf[len] = '\0';
 342
 343                 lwsl_notice("LWS_CALLBACK_HTTP_BODY: %s... len %d\n",
 344                                 (const char *)buf, (int)len);
 345
 346                 break;
 347
 348         case LWS_CALLBACK_HTTP_BODY_COMPLETION:
 349                 lwsl_notice("LWS_CALLBACK_HTTP_BODY_COMPLETION\n");
 350                 /* the whole of the sent body arrived, close or reuse the connection */
 351                 lws_return_http_status(wsi, HTTP_STATUS_OK, NULL);
 352                 goto try_to_reuse;
 353
 354         case LWS_CALLBACK_HTTP_FILE_COMPLETION:
 355                 goto try_to_reuse;
 356
 357         case LWS_CALLBACK_HTTP_WRITEABLE:
 358                 lwsl_info("LWS_CALLBACK_HTTP_WRITEABLE\n");
 359
 360                 if (pss->fd == LWS_INVALID_FILE)
 361                         goto try_to_reuse;
 362 #ifdef LWS_WITH_CGI
 363                 if (pss->reason_bf) {
 364                         lwsl_debug("%s: stdout\n", __func__);
 365                         n = read(lws_get_socket_fd(pss->args.stdwsi[LWS_STDOUT]),
 366                                         buf + LWS_PRE, sizeof(buf) - LWS_PRE);
 367                         //lwsl_notice("read %d (errno %d)\n", n, errno);
 368                         if (n < 0 && errno != EAGAIN)
 369                                 return -1;
 370                         if (n > 0) {
 371                                 m = lws_write(wsi, (unsigned char *)buf + LWS_PRE, n,
 372                                               LWS_WRITE_HTTP);
 373                                 //lwsl_notice("write %d\n", m);
 374                                 if (m < 0)
 375                                         goto bail;
 376                                 pss->reason_bf = 0;
 377                         }
 378                         break;
 379                 }
 380 #endif
 381                 /*
 382                  * we can send more of whatever it is we were sending
 383                  */
 384                 sent = 0;
 385                 do {
 386                         /* we'd like the send this much */
 387                         n = sizeof(buffer) - LWS_PRE;
 388
 389                         /* but if the peer told us he wants less, we can adapt */
 390                         m = lws_get_peer_write_allowance(wsi);
 391
 392                         /* -1 means not using a protocol that has this info */
 393                         if (m == 0)
 394                                 /* right now, peer can't handle anything */
 395                                 goto later;
 396
 397                         if (m != -1 && m < n)
 398                                 /* he couldn't handle that much */
 399                                 n = m;
 400
 401                         n = lws_plat_file_read(wsi, pss->fd,
 402                                                &amount, buffer + LWS_PRE, n);
 403                         /* problem reading, close conn */
 404                         if (n < 0) {
 405                                 lwsl_err("problem reading file\n");
 406                                 goto bail;
 407                         }
 408                         n = (int)amount;
 409                         /* sent it all, close conn */
 410                         if (n == 0)
 411                                 goto penultimate;
 412                         /*
 413                          * To support HTTP2, must take care about preamble space
 414                          *
 415                          * identification of when we send the last payload frame
 416                          * is handled by the library itself if you sent a
 417                          * content-length header
 418                          */
 419                         m = lws_write(wsi, buffer + LWS_PRE, n, LWS_WRITE_HTTP);
 420                         if (m < 0) {
 421                                 lwsl_err("write failed\n");
 422                                 /* write failed, close conn */
 423                                 goto bail;
 424                         }
 425                         if (m) /* while still active, extend timeout */
 426                                 lws_set_timeout(wsi, PENDING_TIMEOUT_HTTP_CONTENT, 5);
 427                         sent += m;
 428
 429                 } while (!lws_send_pipe_choked(wsi) && (sent < 1024 * 1024));
 430 later:
 431                 lws_callback_on_writable(wsi);
 432                 break;
 433 penultimate:
 434                 lws_plat_file_close(wsi, pss->fd);
 435                 pss->fd = LWS_INVALID_FILE;
 436                 goto try_to_reuse;
 437
 438 bail:
 439                 lws_plat_file_close(wsi, pss->fd);
 440
 441                 return -1;
 442
 443         /*
 444          * callback for confirming to continue with client IP appear in
 445          * protocol 0 callback since no websocket protocol has been agreed
 446          * yet.  You can just ignore this if you won't filter on client IP
 447          * since the default uhandled callback return is 0 meaning let the
 448          * connection continue.
 449          */
 450         case LWS_CALLBACK_FILTER_NETWORK_CONNECTION:
 451                 /* if we returned non-zero from here, we kill the connection */
 452                 break;
 453
 454 #ifdef LWS_WITH_CGI
 455         /* CGI IO events (POLLIN/OUT) appear here our demo user code policy is
 456          *
 457          *  - POST data goes on subprocess stdin
 458          *  - subprocess stdout goes on http via writeable callback
 459          *  - subprocess stderr goes to the logs
 460          */
 461         case LWS_CALLBACK_CGI:
 462                 pss->args = *((struct lws_cgi_args *)in);
 463                 //lwsl_notice("LWS_CALLBACK_CGI: ch %d\n", pss->args.ch);
 464                 switch (pss->args.ch) { /* which of stdin/out/err ? */
 465                 case LWS_STDIN:
 466                         /* TBD stdin rx flow control */
 467                         break;
 468                 case LWS_STDOUT:
 469                         pss->reason_bf |= 1 << pss->args.ch;
 470                         /* when writing to MASTER would not block */
 471                         lws_callback_on_writable(wsi);
 472                         break;
 473                 case LWS_STDERR:
 474                         n = read(lws_get_socket_fd(pss->args.stdwsi[LWS_STDERR]),
 475                                         buf, 127);
 476                         //lwsl_notice("stderr reads %d\n", n);
 477                         if (n > 0) {
 478                                 if (buf[n - 1] != '\n')
 479                                         buf[n++] = '\n';
 480                                 buf[n] = '\0';
 481                                 lwsl_notice("CGI-stderr: %s\n", buf);
 482                         }
 483                         break;
 484                 }
 485                 break;
 486
 487         case LWS_CALLBACK_CGI_TERMINATED:
 488                 lwsl_notice("LWS_CALLBACK_CGI_TERMINATED\n");
 489                 /* because we sent on openended http, close the connection */
 490                 return -1;
 491
 492         case LWS_CALLBACK_CGI_STDIN_DATA:  /* POST body for stdin */
 493                 lwsl_notice("LWS_CALLBACK_CGI_STDIN_DATA\n");
 494                 pss->args = *((struct lws_cgi_args *)in);
 495                 n = write(lws_get_socket_fd(pss->args.stdwsi[LWS_STDIN]),
 496                           pss->args.data, pss->args.len);
 497                 lwsl_notice("LWS_CALLBACK_CGI_STDIN_DATA: write says %d", n);
 498                 if (n < pss->args.len)
 499                         lwsl_notice("LWS_CALLBACK_CGI_STDIN_DATA: sent %d only %d went",
 500                                         n, pss->args.len);
 501                 return n;
 502 #endif
 503
 504         /*
 505          * callbacks for managing the external poll() array appear in
 506          * protocol 0 callback
 507          */
 508
 509         case LWS_CALLBACK_LOCK_POLL:
 510                 /*
 511                  * lock mutex to protect pollfd state
 512                  * called before any other POLL related callback
 513                  * if protecting wsi lifecycle change, len == 1
 514                  */
 515                 test_server_lock(len);
 516                 break;
 517
 518         case LWS_CALLBACK_UNLOCK_POLL:
 519                 /*
 520                  * unlock mutex to protect pollfd state when
 521                  * called after any other POLL related callback
 522                  * if protecting wsi lifecycle change, len == 1
 523                  */
 524                 test_server_unlock(len);
 525                 break;
 526
 527 #ifdef EXTERNAL_POLL
 528         case LWS_CALLBACK_ADD_POLL_FD:
 529
 530                 if (count_pollfds >= max_poll_elements) {
 531                         lwsl_err("LWS_CALLBACK_ADD_POLL_FD: too many sockets to track\n");
 532                         return 1;
 533                 }
 534
 535                 fd_lookup[pa->fd] = count_pollfds;
 536                 pollfds[count_pollfds].fd = pa->fd;
 537                 pollfds[count_pollfds].events = pa->events;
 538                 pollfds[count_pollfds++].revents = 0;
 539                 break;
 540
 541         case LWS_CALLBACK_DEL_POLL_FD:
 542                 if (!--count_pollfds)
 543                         break;
 544                 m = fd_lookup[pa->fd];
 545                 /* have the last guy take up the vacant slot */
 546                 pollfds[m] = pollfds[count_pollfds];
 547                 fd_lookup[pollfds[count_pollfds].fd] = m;
 548                 break;
 549
 550         case LWS_CALLBACK_CHANGE_MODE_POLL_FD:
 551                 pollfds[fd_lookup[pa->fd]].events = pa->events;
 552                 break;
 553 #endif
 554
 555         case LWS_CALLBACK_GET_THREAD_ID:
 556                 /*
 557                  * if you will call "lws_callback_on_writable"
 558                  * from a different thread, return the caller thread ID
 559                  * here so lws can use this information to work out if it
 560                  * should signal the poll() loop to exit and restart early
 561                  */
 562
 563                 /* return pthread_getthreadid_np(); */
 564
 565                 break;
 566
 567         default:
 568                 break;
 569         }
 570
 571         return 0;
 572
 573         /* if we're on HTTP1.1 or 2.0, will keep the idle connection alive */
 574 try_to_reuse:
 575         if (lws_http_transaction_completed(wsi))
 576                 return -1;
 577
 578         return 0;
 579 }