lib/context.c

   1 /*
   2  * libwebsockets - small server side websockets and web server implementation
   3  *
   4  * Copyright (C) 2010-2015 Andy Green <andy@warmcat.com>
   5  *
   6  *  This library is free software; you can redistribute it and/or
   7  *  modify it under the terms of the GNU Lesser General Public
   8  *  License as published by the Free Software Foundation:
   9  *  version 2.1 of the License.
  10  *
  11  *  This library is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  *  Lesser General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU Lesser General Public
  17  *  License along with this library; if not, write to the Free Software
  18  *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
  19  *  MA  02110-1301  USA
  20  */
  21
  22 #include "private-libwebsockets.h"
  23
  24 #ifndef LWS_BUILD_HASH
  25 #define LWS_BUILD_HASH "unknown-build-hash"
  26 #endif
  27
  28 static const char *library_version = LWS_LIBRARY_VERSION " " LWS_BUILD_HASH;
  29
  30 /**
  31  * lws_get_library_version: get version and git hash library built from
  32  *
  33  *      returns a const char * to a string like "1.1 178d78c"
  34  *      representing the library version followed by the git head hash it
  35  *      was built from
  36  */
  37 LWS_VISIBLE const char *
  38 lws_get_library_version(void)
  39 {
  40         return library_version;
  41 }
  42
  43 /**
  44  * lws_create_context() - Create the websocket handler
  45  * @info:       pointer to struct with parameters
  46  *
  47  *      This function creates the listening socket (if serving) and takes care
  48  *      of all initialization in one step.
  49  *
  50  *      After initialization, it returns a struct lws_context * that
  51  *      represents this server.  After calling, user code needs to take care
  52  *      of calling lws_service() with the context pointer to get the
  53  *      server's sockets serviced.  This must be done in the same process
  54  *      context as the initialization call.
  55  *
  56  *      The protocol callback functions are called for a handful of events
  57  *      including http requests coming in, websocket connections becoming
  58  *      established, and data arriving; it's also called periodically to allow
  59  *      async transmission.
  60  *
  61  *      HTTP requests are sent always to the FIRST protocol in @protocol, since
  62  *      at that time websocket protocol has not been negotiated.  Other
  63  *      protocols after the first one never see any HTTP callack activity.
  64  *
  65  *      The server created is a simple http server by default; part of the
  66  *      websocket standard is upgrading this http connection to a websocket one.
  67  *
  68  *      This allows the same server to provide files like scripts and favicon /
  69  *      images or whatever over http and dynamic data over websockets all in
  70  *      one place; they're all handled in the user callback.
  71  */
  72 LWS_VISIBLE struct lws_context *
  73 lws_create_context(struct lws_context_creation_info *info)
  74 {
  75         struct lws_context *context = NULL;
  76         struct lws wsi;
  77 #ifndef LWS_NO_DAEMONIZE
  78         int pid_daemon = get_daemonize_pid();
  79 #endif
  80         char *p;
  81         int n, m;
  82 #if defined(__ANDROID__)
  83         struct rlimit rt;
  84 #endif
  85
  86
  87         lwsl_notice("Initial logging level %d\n", log_level);
  88         lwsl_notice("Libwebsockets version: %s\n", library_version);
  89 #if LWS_POSIX
  90 #ifdef LWS_USE_IPV6
  91         if (!(info->options & LWS_SERVER_OPTION_DISABLE_IPV6))
  92                 lwsl_notice("IPV6 compiled in and enabled\n");
  93         else
  94                 lwsl_notice("IPV6 compiled in but disabled\n");
  95 #else
  96         lwsl_notice("IPV6 not compiled in\n");
  97 #endif
  98         lws_feature_status_libev(info);
  99 #endif
 100         lwsl_info(" LWS_DEF_HEADER_LEN    : %u\n", LWS_DEF_HEADER_LEN);
 101         lwsl_info(" LWS_MAX_PROTOCOLS     : %u\n", LWS_MAX_PROTOCOLS);
 102         lwsl_info(" LWS_MAX_SMP           : %u\n", LWS_MAX_SMP);
 103         lwsl_info(" SPEC_LATEST_SUPPORTED : %u\n", SPEC_LATEST_SUPPORTED);
 104         lwsl_info(" sizeof (*info)        : %u\n", sizeof(*info));
 105 #if LWS_POSIX
 106         lwsl_info(" SYSTEM_RANDOM_FILEPATH: '%s'\n", SYSTEM_RANDOM_FILEPATH);
 107 #endif
 108         if (lws_plat_context_early_init())
 109                 return NULL;
 110
 111         context = lws_zalloc(sizeof(struct lws_context));
 112         if (!context) {
 113                 lwsl_err("No memory for websocket context\n");
 114                 return NULL;
 115         }
 116 #ifndef LWS_NO_DAEMONIZE
 117         if (pid_daemon) {
 118                 context->started_with_parent = pid_daemon;
 119                 lwsl_notice(" Started with daemon pid %d\n", pid_daemon);
 120         }
 121 #endif
 122 #if defined(__ANDROID__)
 123                 n = getrlimit ( RLIMIT_NOFILE,&rt);
 124                 if (-1 == n) {
 125                         lwsl_err("Get RLIMIT_NOFILE failed!\n");
 126                         return NULL;
 127                 }
 128                 context->max_fds = rt.rlim_cur;
 129 #else
 130                 context->max_fds = getdtablesize();
 131 #endif
 132
 133         if (info->count_threads)
 134                 context->count_threads = info->count_threads;
 135         else
 136                 context->count_threads = 1;
 137
 138         if (context->count_threads > LWS_MAX_SMP)
 139                 context->count_threads = LWS_MAX_SMP;
 140
 141         context->protocols = info->protocols;
 142         context->token_limits = info->token_limits;
 143         context->listen_port = info->port;
 144         context->http_proxy_port = 0;
 145         context->http_proxy_address[0] = '\0';
 146         context->options = info->options;
 147         context->iface = info->iface;
 148         context->ka_time = info->ka_time;
 149         context->ka_interval = info->ka_interval;
 150         context->ka_probes = info->ka_probes;
 151         if (info->timeout_secs)
 152                 context->timeout_secs = info->timeout_secs;
 153         else
 154                 context->timeout_secs = AWAITING_TIMEOUT;
 155
 156         lwsl_info(" default timeout (secs): %u\n", context->timeout_secs);
 157
 158         if (info->max_http_header_data)
 159                 context->max_http_header_data = info->max_http_header_data;
 160         else
 161                 context->max_http_header_data = LWS_DEF_HEADER_LEN;
 162         if (info->max_http_header_pool)
 163                 context->max_http_header_pool = info->max_http_header_pool;
 164         else
 165                 context->max_http_header_pool = LWS_DEF_HEADER_POOL;
 166
 167         /*
 168          * Allocate the per-thread storage for scratchpad buffers,
 169          * and header data pool
 170          */
 171         for (n = 0; n < context->count_threads; n++) {
 172                 context->pt[n].serv_buf = lws_zalloc(LWS_MAX_SOCKET_IO_BUF);
 173                 if (!context->pt[n].serv_buf) {
 174                         lwsl_err("OOM\n");
 175                         return NULL;
 176                 }
 177
 178                 context->pt[n].context = context;
 179                 context->pt[n].tid = n;
 180                 context->pt[n].http_header_data = lws_malloc(context->max_http_header_data *
 181                                                        context->max_http_header_pool);
 182                 if (!context->pt[n].http_header_data)
 183                         goto bail;
 184
 185                 context->pt[n].ah_pool = lws_zalloc(sizeof(struct allocated_headers) *
 186                                               context->max_http_header_pool);
 187                 for (m = 0; m < context->max_http_header_pool; m++)
 188                         context->pt[n].ah_pool[m].data =
 189                                 (char *)context->pt[n].http_header_data +
 190                                 (m * context->max_http_header_data);
 191                 if (!context->pt[n].ah_pool)
 192                         goto bail;
 193
 194                 lws_pt_mutex_init(&context->pt[n]);
 195         }
 196
 197         if (info->fd_limit_per_thread)
 198                 context->fd_limit_per_thread = info->fd_limit_per_thread;
 199         else
 200                 context->fd_limit_per_thread = context->max_fds /
 201                                                context->count_threads;
 202
 203         lwsl_notice(" Threads: %d each %d fds\n", context->count_threads,
 204                     context->fd_limit_per_thread);
 205
 206         memset(&wsi, 0, sizeof(wsi));
 207         wsi.context = context;
 208
 209         if (!info->ka_interval && info->ka_time > 0) {
 210                 lwsl_err("info->ka_interval can't be 0 if ka_time used\n");
 211                 return NULL;
 212         }
 213
 214 #ifdef LWS_USE_LIBEV
 215         /* (Issue #264) In order to *avoid breaking backwards compatibility*, we
 216          * enable libev mediated SIGINT handling with a default handler of
 217          * lws_sigint_cb. The handler can be overridden or disabled
 218          * by invoking lws_sigint_cfg after creating the context, but
 219          * before invoking lws_initloop:
 220          */
 221         context->use_ev_sigint = 1;
 222         context->lws_ev_sigint_cb = &lws_ev_sigint_cb;
 223 #endif /* LWS_USE_LIBEV */
 224 #ifdef LWS_USE_LIBUV
 225         /* (Issue #264) In order to *avoid breaking backwards compatibility*, we
 226          * enable libev mediated SIGINT handling with a default handler of
 227          * lws_sigint_cb. The handler can be overridden or disabled
 228          * by invoking lws_sigint_cfg after creating the context, but
 229          * before invoking lws_initloop:
 230          */
 231         context->use_ev_sigint = 1;
 232         context->lws_uv_sigint_cb = &lws_uv_sigint_cb;
 233 #endif
 234
 235         lwsl_info(" mem: context:         %5u bytes (%d ctx + (%d thr x %d))\n",
 236                   sizeof(struct lws_context) +
 237                   (context->count_threads * LWS_MAX_SOCKET_IO_BUF),
 238                   sizeof(struct lws_context),
 239                   context->count_threads,
 240                   LWS_MAX_SOCKET_IO_BUF);
 241
 242         lwsl_info(" mem: http hdr rsvd:   %5u bytes (%u thr x (%u + %u) x %u))\n",
 243                     (context->max_http_header_data +
 244                      sizeof(struct allocated_headers)) *
 245                     context->max_http_header_pool * context->count_threads,
 246                     context->count_threads,
 247                     context->max_http_header_data,
 248                     sizeof(struct allocated_headers),
 249                     context->max_http_header_pool);
 250         n = sizeof(struct lws_pollfd) * context->count_threads *
 251             context->fd_limit_per_thread;
 252         context->pt[0].fds = lws_zalloc(n);
 253         if (context->pt[0].fds == NULL) {
 254                 lwsl_err("OOM allocating %d fds\n", context->max_fds);
 255                 goto bail;
 256         }
 257         lwsl_info(" mem: pollfd map:      %5u\n", n);
 258
 259 #if LWS_MAX_SMP > 1
 260         /* each thread serves his own chunk of fds */
 261         for (n = 1; n < (int)info->count_threads; n++)
 262                 context->pt[n].fds = context->pt[n - 1].fds +
 263                                      context->fd_limit_per_thread;
 264 #endif
 265
 266         if (lws_plat_init(context, info))
 267                 goto bail;
 268
 269         lws_context_init_extensions(info, context);
 270
 271         context->user_space = info->user;
 272
 273         lwsl_notice(" mem: per-conn:        %5u bytes + protocol rx buf\n",
 274                     sizeof(struct lws));
 275
 276         strcpy(context->canonical_hostname, "unknown");
 277         lws_server_get_canonical_hostname(context, info);
 278
 279         /* either use proxy from info, or try get it from env var */
 280
 281         if (info->http_proxy_address) {
 282                 /* override for backwards compatibility */
 283                 if (info->http_proxy_port)
 284                         context->http_proxy_port = info->http_proxy_port;
 285                 lws_set_proxy(context, info->http_proxy_address);
 286         } else {
 287 #ifdef LWS_HAVE_GETENV
 288                 p = getenv("http_proxy");
 289                 if (p)
 290                         lws_set_proxy(context, p);
 291 #endif
 292         }
 293
 294         if (lws_context_init_server_ssl(info, context))
 295                 goto bail;
 296
 297         if (lws_context_init_client_ssl(info, context))
 298                 goto bail;
 299
 300         if (lws_context_init_server(info, context))
 301                 goto bail;
 302
 303         /*
 304          * drop any root privs for this process
 305          * to listen on port < 1023 we would have needed root, but now we are
 306          * listening, we don't want the power for anything else
 307          */
 308         lws_plat_drop_app_privileges(info);
 309
 310         /* initialize supported protocols */
 311
 312         for (context->count_protocols = 0;
 313              info->protocols[context->count_protocols].callback;
 314              context->count_protocols++)
 315                 /*
 316                  * inform all the protocols that they are doing their one-time
 317                  * initialization if they want to.
 318                  *
 319                  * NOTE the wsi is all zeros except for the context pointer
 320                  * so lws_get_context(wsi) can work in the callback.
 321                  */
 322                 info->protocols[context->count_protocols].callback(&wsi,
 323                                 LWS_CALLBACK_PROTOCOL_INIT, NULL, NULL, 0);
 324
 325         /*
 326          * give all extensions a chance to create any per-context
 327          * allocations they need
 328          */
 329         if (info->port != CONTEXT_PORT_NO_LISTEN) {
 330                 if (lws_ext_cb_all_exts(context, NULL,
 331                         LWS_EXT_CB_SERVER_CONTEXT_CONSTRUCT, NULL, 0) < 0)
 332                         goto bail;
 333         } else
 334                 if (lws_ext_cb_all_exts(context, NULL,
 335                         LWS_EXT_CB_CLIENT_CONTEXT_CONSTRUCT, NULL, 0) < 0)
 336                         goto bail;
 337
 338         return context;
 339
 340 bail:
 341         lws_context_destroy(context);
 342         return NULL;
 343 }
 344
 345 /**
 346  * lws_context_destroy() - Destroy the websocket context
 347  * @context:    Websocket context
 348  *
 349  *      This function closes any active connections and then frees the
 350  *      context.  After calling this, any further use of the context is
 351  *      undefined.
 352  */
 353 LWS_VISIBLE void
 354 lws_context_destroy(struct lws_context *context)
 355 {
 356         const struct lws_protocols *protocol = NULL;
 357         struct lws_context_per_thread *pt;
 358         struct lws wsi;
 359         int n, m;
 360
 361         lwsl_notice("%s\n", __func__);
 362
 363         if (!context)
 364                 return;
 365
 366         m = context->count_threads;
 367         context->being_destroyed = 1;
 368
 369         memset(&wsi, 0, sizeof(wsi));
 370         wsi.context = context;
 371
 372 #ifdef LWS_LATENCY
 373         if (context->worst_latency_info[0])
 374                 lwsl_notice("Worst latency: %s\n", context->worst_latency_info);
 375 #endif
 376
 377         while (m--) {
 378                 pt = &context->pt[m];
 379
 380                 for (n = 0; (unsigned int)n < context->pt[m].fds_count; n++) {
 381                         struct lws *wsi = wsi_from_fd(context, pt->fds[n].fd);
 382                         if (!wsi)
 383                                 continue;
 384
 385                         lws_close_free_wsi(wsi,
 386                                 LWS_CLOSE_STATUS_NOSTATUS_CONTEXT_DESTROY
 387                                 /* no protocol close */);
 388                         n--;
 389                 }
 390                 lws_pt_mutex_destroy(pt);
 391         }
 392         /*
 393          * give all extensions a chance to clean up any per-context
 394          * allocations they might have made
 395          */
 396
 397         n = lws_ext_cb_all_exts(context, NULL,
 398                                 LWS_EXT_CB_SERVER_CONTEXT_DESTRUCT, NULL, 0);
 399
 400         n = lws_ext_cb_all_exts(context, NULL,
 401                                 LWS_EXT_CB_CLIENT_CONTEXT_DESTRUCT, NULL, 0);
 402
 403         /*
 404          * inform all the protocols that they are done and will have no more
 405          * callbacks
 406          */
 407         protocol = context->protocols;
 408         if (protocol)
 409                 while (protocol->callback) {
 410                         protocol->callback(&wsi, LWS_CALLBACK_PROTOCOL_DESTROY,
 411                                            NULL, NULL, 0);
 412                         protocol++;
 413                 }
 414
 415         for (n = 0; n < context->count_threads; n++) {
 416                 pt = &context->pt[n];
 417
 418                 lws_libev_destroyloop(context, n);
 419                 lws_libuv_destroyloop(context, n);
 420
 421                 lws_free_set_NULL(context->pt[n].serv_buf);
 422                 if (pt->ah_pool)
 423                         lws_free(pt->ah_pool);
 424                 if (pt->http_header_data)
 425                         lws_free(pt->http_header_data);
 426         }
 427         lws_plat_context_early_destroy(context);
 428         lws_ssl_context_destroy(context);
 429         if (context->pt[0].fds)
 430                 lws_free_set_NULL(context->pt[0].fds);
 431
 432         lws_plat_context_late_destroy(context);
 433
 434         lws_free(context);
 435 }