lib/client-handshake.c

   1 #include "private-libwebsockets.h"
   2
   3 struct lws *
   4 lws_client_connect_2(struct lws *wsi)
   5 {
   6 #ifdef LWS_USE_IPV6
   7         struct sockaddr_in6 server_addr6;
   8         struct sockaddr_in6 client_addr6;
   9         struct addrinfo hints, *result;
  10 #endif
  11         struct lws_context *context = wsi->context;
  12         struct lws_context_per_thread *pt = &context->pt[(int)wsi->tsi];
  13         struct sockaddr_in server_addr4;
  14         struct sockaddr_in client_addr4;
  15         struct lws_pollfd pfd;
  16         struct sockaddr *v;
  17         int n, plen = 0;
  18         const char *ads;
  19
  20         lwsl_client("%s\n", __func__);
  21
  22         /* proxy? */
  23
  24         if (context->http_proxy_port) {
  25                 plen = sprintf((char *)pt->serv_buf,
  26                         "CONNECT %s:%u HTTP/1.0\x0d\x0a"
  27                         "User-agent: libwebsockets\x0d\x0a",
  28                         lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_PEER_ADDRESS),
  29                         wsi->u.hdr.ah->c_port);
  30
  31                 if (context->proxy_basic_auth_token[0])
  32                         plen += sprintf((char *)pt->serv_buf + plen,
  33                                         "Proxy-authorization: basic %s\x0d\x0a",
  34                                         context->proxy_basic_auth_token);
  35
  36                 plen += sprintf((char *)pt->serv_buf + plen, "\x0d\x0a");
  37                 ads = context->http_proxy_address;
  38
  39 #ifdef LWS_USE_IPV6
  40                 if (LWS_IPV6_ENABLED(context)) {
  41                         memset(&server_addr6, 0, sizeof(struct sockaddr_in6));
  42                         server_addr6.sin6_port = htons(context->http_proxy_port);
  43                 } else
  44 #endif
  45                         server_addr4.sin_port = htons(context->http_proxy_port);
  46
  47         } else {
  48                 ads = lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_PEER_ADDRESS);
  49 #ifdef LWS_USE_IPV6
  50                 if (LWS_IPV6_ENABLED(context)) {
  51                         memset(&server_addr6, 0, sizeof(struct sockaddr_in6));
  52                         server_addr6.sin6_port = htons(wsi->u.hdr.ah->c_port);
  53                 } else
  54 #endif
  55                         server_addr4.sin_port = htons(wsi->u.hdr.ah->c_port);
  56         }
  57
  58         /*
  59          * prepare the actual connection (to the proxy, if any)
  60          */
  61        lwsl_client("%s: address %s\n", __func__, ads);
  62
  63 #ifdef LWS_USE_IPV6
  64         if (LWS_IPV6_ENABLED(context)) {
  65                 memset(&hints, 0, sizeof(struct addrinfo));
  66 #if !defined(__ANDROID__)
  67                 hints.ai_family = AF_INET6;
  68                 hints.ai_flags = AI_V4MAPPED;
  69 #endif
  70                 n = getaddrinfo(ads, NULL, &hints, &result);
  71                 if (n) {
  72 #ifdef _WIN32
  73                         lwsl_err("getaddrinfo: %ls\n", gai_strerrorW(n));
  74 #else
  75                         lwsl_err("getaddrinfo: %s\n", gai_strerror(n));
  76 #endif
  77                         goto oom4;
  78                 }
  79
  80                 server_addr6.sin6_family = AF_INET6;
  81                 switch (result->ai_family) {
  82 #if defined(__ANDROID__)
  83                 case AF_INET:
  84                         /* map IPv4 to IPv6 */
  85                         bzero((char *)&server_addr6.sin6_addr,
  86                                                 sizeof(struct in6_addr));
  87                         server_addr6.sin6_addr.s6_addr[10] = 0xff;
  88                         server_addr6.sin6_addr.s6_addr[11] = 0xff;
  89                         memcpy(&server_addr6.sin6_addr.s6_addr[12],
  90                                 &((struct sockaddr_in *)result->ai_addr)->sin_addr,
  91                                                         sizeof(struct in_addr));
  92                         break;
  93 #endif
  94                 case AF_INET6:
  95                         memcpy(&server_addr6.sin6_addr,
  96                           &((struct sockaddr_in6 *)result->ai_addr)->sin6_addr,
  97                                                 sizeof(struct in6_addr));
  98                         break;
  99                 default:
 100                         lwsl_err("Unknown address family\n");
 101                         freeaddrinfo(result);
 102                         goto oom4;
 103                 }
 104
 105                 freeaddrinfo(result);
 106         } else
 107 #endif
 108         {
 109                 struct addrinfo ai, *res, *result;
 110                 void *p = NULL;
 111
 112                 memset (&ai, 0, sizeof ai);
 113                 ai.ai_family = PF_UNSPEC;
 114                 ai.ai_socktype = SOCK_STREAM;
 115                 ai.ai_flags = AI_CANONNAME;
 116
 117                 if (getaddrinfo(ads, NULL, &ai, &result))
 118                         goto oom4;
 119
 120                 res = result;
 121                 while (!p && res) {
 122                         switch (res->ai_family) {
 123                         case AF_INET:
 124                                 p = &((struct sockaddr_in *)res->ai_addr)->sin_addr;
 125                                 break;
 126                         }
 127
 128                         res = res->ai_next;
 129                 }
 130
 131                 if (!p) {
 132                         freeaddrinfo(result);
 133                         goto oom4;
 134                 }
 135
 136                 server_addr4.sin_family = AF_INET;
 137                 server_addr4.sin_addr = *((struct in_addr *)p);
 138                 bzero(&server_addr4.sin_zero, 8);
 139                 freeaddrinfo(result);
 140         }
 141
 142         if (!lws_socket_is_valid(wsi->sock)) {
 143
 144 #ifdef LWS_USE_IPV6
 145                 if (LWS_IPV6_ENABLED(context))
 146                         wsi->sock = socket(AF_INET6, SOCK_STREAM, 0);
 147                 else
 148 #endif
 149                         wsi->sock = socket(AF_INET, SOCK_STREAM, 0);
 150
 151                 if (!lws_socket_is_valid(wsi->sock)) {
 152                         lwsl_warn("Unable to open socket\n");
 153                         goto oom4;
 154                 }
 155
 156                 if (lws_plat_set_socket_options(context, wsi->sock)) {
 157                         lwsl_err("Failed to set wsi socket options\n");
 158                         compatible_close(wsi->sock);
 159                         goto oom4;
 160                 }
 161
 162                 wsi->mode = LWSCM_WSCL_WAITING_CONNECT;
 163
 164                 lws_libev_accept(wsi, wsi->sock);
 165                 if (insert_wsi_socket_into_fds(context, wsi)) {
 166                         compatible_close(wsi->sock);
 167                         goto oom4;
 168                 }
 169
 170                 /*
 171                  * past here, we can't simply free the structs as error
 172                  * handling as oom4 does.  We have to run the whole close flow.
 173                  */
 174
 175                 lws_set_timeout(wsi,
 176                         PENDING_TIMEOUT_AWAITING_CONNECT_RESPONSE,
 177                                                               AWAITING_TIMEOUT);
 178 #ifdef LWS_USE_IPV6
 179                 if (LWS_IPV6_ENABLED(context)) {
 180                         v = (struct sockaddr *)&client_addr6;
 181                         n = sizeof(client_addr6);
 182                         bzero((char *)v, n);
 183                         client_addr6.sin6_family = AF_INET6;
 184                 } else
 185 #endif
 186                 {
 187                         v = (struct sockaddr *)&client_addr4;
 188                         n = sizeof(client_addr4);
 189                         bzero((char *)v, n);
 190                         client_addr4.sin_family = AF_INET;
 191                 }
 192
 193                 if (context->iface) {
 194                         if (interface_to_sa(context, context->iface,
 195                                         (struct sockaddr_in *)v, n) < 0) {
 196                                 lwsl_err("Unable to find interface %s\n",
 197                                                                 context->iface);
 198                                 goto failed;
 199                         }
 200
 201                         if (bind(wsi->sock, v, n) < 0) {
 202                                 lwsl_err("Error binding to interface %s",
 203                                                                 context->iface);
 204                                 goto failed;
 205                         }
 206                 }
 207         }
 208
 209 #ifdef LWS_USE_IPV6
 210         if (LWS_IPV6_ENABLED(context)) {
 211                 v = (struct sockaddr *)&server_addr6;
 212                 n = sizeof(struct sockaddr_in6);
 213         } else
 214 #endif
 215         {
 216                 v = (struct sockaddr *)&server_addr4;
 217                 n = sizeof(struct sockaddr);
 218         }
 219
 220         if (connect(wsi->sock, v, n) == -1 || LWS_ERRNO == LWS_EISCONN) {
 221                 if (LWS_ERRNO == LWS_EALREADY ||
 222                     LWS_ERRNO == LWS_EINPROGRESS ||
 223                     LWS_ERRNO == LWS_EWOULDBLOCK
 224 #ifdef _WIN32
 225                         || LWS_ERRNO == WSAEINVAL
 226 #endif
 227                 ) {
 228                         lwsl_client("nonblocking connect retry\n");
 229
 230                         /*
 231                          * must do specifically a POLLOUT poll to hear
 232                          * about the connect completion
 233                          */
 234                         if (lws_change_pollfd(wsi, 0, LWS_POLLOUT))
 235                                 goto failed;
 236
 237                         return wsi;
 238                 }
 239
 240                 if (LWS_ERRNO != LWS_EISCONN) {
 241                         lwsl_debug("Connect failed errno=%d\n", LWS_ERRNO);
 242                         goto failed;
 243                 }
 244         }
 245
 246         lwsl_client("connected\n");
 247
 248         /* we are connected to server, or proxy */
 249
 250         if (context->http_proxy_port) {
 251
 252                 /*
 253                  * OK from now on we talk via the proxy, so connect to that
 254                  *
 255                  * (will overwrite existing pointer,
 256                  * leaving old string/frag there but unreferenced)
 257                  */
 258                 if (lws_hdr_simple_create(wsi, _WSI_TOKEN_CLIENT_PEER_ADDRESS,
 259                                           context->http_proxy_address))
 260                         goto failed;
 261                 wsi->u.hdr.ah->c_port = context->http_proxy_port;
 262
 263                 n = send(wsi->sock, (char *)pt->serv_buf, plen,
 264                          MSG_NOSIGNAL);
 265                 if (n < 0) {
 266                         lwsl_debug("ERROR writing to proxy socket\n");
 267                         goto failed;
 268                 }
 269
 270                 lws_set_timeout(wsi, PENDING_TIMEOUT_AWAITING_PROXY_RESPONSE,
 271                                 AWAITING_TIMEOUT);
 272
 273                 wsi->mode = LWSCM_WSCL_WAITING_PROXY_REPLY;
 274
 275                 return wsi;
 276         }
 277
 278         /*
 279          * provoke service to issue the handshake directly
 280          * we need to do it this way because in the proxy case, this is the
 281          * next state and executed only if and when we get a good proxy
 282          * response inside the state machine... but notice in SSL case this
 283          * may not have sent anything yet with 0 return, and won't until some
 284          * many retries from main loop.  To stop that becoming endless,
 285          * cover with a timeout.
 286          */
 287
 288         lws_set_timeout(wsi, PENDING_TIMEOUT_SENT_CLIENT_HANDSHAKE,
 289                         AWAITING_TIMEOUT);
 290
 291         wsi->mode = LWSCM_WSCL_ISSUE_HANDSHAKE;
 292         pfd.fd = wsi->sock;
 293         pfd.revents = LWS_POLLIN;
 294
 295         n = lws_service_fd(context, &pfd);
 296         if (n < 0)
 297                 goto failed;
 298         if (n) /* returns 1 on failure after closing wsi */
 299                 return NULL;
 300
 301         return wsi;
 302
 303 oom4:
 304         /* we're closing, losing some rx is OK */
 305         wsi->u.hdr.ah->rxpos = wsi->u.hdr.ah->rxlen;
 306         lws_header_table_detach(wsi, 0);
 307         lws_free(wsi);
 308
 309         return NULL;
 310
 311 failed:
 312         lws_close_free_wsi(wsi, LWS_CLOSE_STATUS_NOSTATUS);
 313
 314         return NULL;
 315 }
 316
 317 /**
 318  * lws_client_reset() - retarget a connected wsi to start over with a new connection (ie, redirect)
 319  *                      this only works if still in HTTP, ie, not upgraded yet
 320  * wsi:         connection to reset
 321  * address:     network address of the new server
 322  * port:        port to connect to
 323  * path:        uri path to connect to on the new server
 324  * host:        host header to send to the new server
 325  */
 326 LWS_VISIBLE struct lws *
 327 lws_client_reset(struct lws *wsi, int ssl, const char *address, int port, const char *path, const char *host)
 328 {
 329         if (wsi->u.hdr.redirects == 3) {
 330                 lwsl_err("%s: Too many redirects\n", __func__);
 331                 return NULL;
 332         }
 333         wsi->u.hdr.redirects++;
 334
 335 #ifdef LWS_OPENSSL_SUPPORT
 336         wsi->use_ssl = ssl;
 337 #else
 338         if (ssl) {
 339                 lwsl_err("%s: not configured for ssl\n", __func__);
 340                 return NULL;
 341         }
 342 #endif
 343
 344         lwsl_notice("redirect ads='%s', port=%d, path='%s'\n", address, port, path);
 345
 346         if (lws_hdr_simple_create(wsi, _WSI_TOKEN_CLIENT_PEER_ADDRESS, address))
 347                 return NULL;
 348
 349         if (lws_hdr_simple_create(wsi, _WSI_TOKEN_CLIENT_URI, path))
 350                 return NULL;
 351
 352         if (lws_hdr_simple_create(wsi, _WSI_TOKEN_CLIENT_HOST, host))
 353                 return NULL;
 354
 355         compatible_close(wsi->sock);
 356         remove_wsi_socket_from_fds(wsi);
 357         wsi->sock = LWS_SOCK_INVALID;
 358         wsi->state = LWSS_CLIENT_UNCONNECTED;
 359         wsi->protocol = NULL;
 360         wsi->pending_timeout = NO_PENDING_TIMEOUT;
 361         wsi->u.hdr.ah->c_port = port;
 362
 363         return lws_client_connect_2(wsi);
 364 }
 365
 366 /**
 367  * lws_client_connect_via_info() - Connect to another websocket server
 368  * @i:pointer to lws_client_connect_info struct
 369  *
 370  *      This function creates a connection to a remote server
 371  */
 372
 373
 374 LWS_VISIBLE struct lws *
 375 lws_client_connect_via_info(struct lws_client_connect_info *i)
 376 {
 377         struct lws *wsi;
 378         int v = SPEC_LATEST_SUPPORTED;
 379
 380         wsi = lws_zalloc(sizeof(struct lws));
 381         if (wsi == NULL)
 382                 goto bail;
 383
 384         wsi->context = i->context;
 385         wsi->sock = LWS_SOCK_INVALID;
 386
 387         /* -1 means just use latest supported */
 388
 389         if (i->ietf_version_or_minus_one != -1 && i->ietf_version_or_minus_one)
 390                 v = i->ietf_version_or_minus_one;
 391
 392         wsi->ietf_spec_revision = v;
 393         wsi->user_space = NULL;
 394         wsi->state = LWSS_CLIENT_UNCONNECTED;
 395         wsi->protocol = NULL;
 396         wsi->pending_timeout = NO_PENDING_TIMEOUT;
 397         wsi->position_in_fds_table = -1;
 398
 399 #ifdef LWS_OPENSSL_SUPPORT
 400         wsi->use_ssl = i->ssl_connection;
 401 #else
 402         if (i->ssl_connection) {
 403                 lwsl_err("libwebsockets not configured for ssl\n");
 404                 goto bail;
 405         }
 406 #endif
 407
 408         if (lws_header_table_attach(wsi, 0))
 409                 goto bail;
 410
 411         /*
 412          * we're not necessarily in a position to action these right away,
 413          * stash them... we only need during connect phase so u.hdr is fine
 414          */
 415         wsi->u.hdr.ah->c_port = i->port;
 416         if (lws_hdr_simple_create(wsi, _WSI_TOKEN_CLIENT_PEER_ADDRESS, i->address))
 417                 goto bail1;
 418
 419         /* these only need u.hdr lifetime as well */
 420
 421         if (lws_hdr_simple_create(wsi, _WSI_TOKEN_CLIENT_URI, i->path))
 422                 goto bail1;
 423
 424         if (lws_hdr_simple_create(wsi, _WSI_TOKEN_CLIENT_HOST, i->host))
 425                 goto bail1;
 426
 427         if (i->origin)
 428                 if (lws_hdr_simple_create(wsi, _WSI_TOKEN_CLIENT_ORIGIN, i->origin))
 429                         goto bail1;
 430         /*
 431          * this is a list of protocols we tell the server we're okay with
 432          * stash it for later when we compare server response with it
 433          */
 434         if (i->protocol)
 435                 if (lws_hdr_simple_create(wsi, _WSI_TOKEN_CLIENT_SENT_PROTOCOLS,
 436                                           i->protocol))
 437                         goto bail1;
 438
 439         wsi->protocol = &i->context->protocols[0];
 440         if (wsi && !wsi->user_space && i->userdata) {
 441                 wsi->user_space_externally_allocated = 1;
 442                 wsi->user_space = i->userdata;
 443         }
 444
 445         /*
 446          * Check with each extension if it is able to route and proxy this
 447          * connection for us.  For example, an extension like x-google-mux
 448          * can handle this and then we don't need an actual socket for this
 449          * connection.
 450          */
 451
 452         if (lws_ext_cb_all_exts(i->context, wsi,
 453                         LWS_EXT_CB_CAN_PROXY_CLIENT_CONNECTION,
 454                                                      (void *)i->address, i->port) > 0) {
 455                 lwsl_client("lws_client_connect: ext handling conn\n");
 456
 457                 lws_set_timeout(wsi,
 458                         PENDING_TIMEOUT_AWAITING_EXTENSION_CONNECT_RESPONSE,
 459                                 AWAITING_TIMEOUT);
 460
 461                 wsi->mode = LWSCM_WSCL_WAITING_EXTENSION_CONNECT;
 462                 return wsi;
 463         }
 464         lwsl_client("lws_client_connect: direct conn\n");
 465
 466         wsi->context->count_wsi_allocated++;
 467
 468         return lws_client_connect_2(wsi);
 469
 470 bail1:
 471         /* we're closing, losing some rx is OK */
 472         wsi->u.hdr.ah->rxpos = wsi->u.hdr.ah->rxlen;
 473         lws_header_table_detach(wsi, 0);
 474 bail:
 475         lws_free(wsi);
 476
 477         return NULL;
 478 }
 479
 480
 481 /**
 482  * lws_client_connect_extended() - Connect to another websocket server
 483  *                              DEPRECATED use lws_client_connect_via_info
 484  * @context:    Websocket context
 485  * @address:    Remote server address, eg, "myserver.com"
 486  * @port:       Port to connect to on the remote server, eg, 80
 487  * @ssl_connection:     0 = ws://, 1 = wss:// encrypted, 2 = wss:// allow self
 488  *                      signed certs
 489  * @path:       Websocket path on server
 490  * @host:       Hostname on server
 491  * @origin:     Socket origin name
 492  * @protocol:   Comma-separated list of protocols being asked for from
 493  *              the server, or just one.  The server will pick the one it
 494  *              likes best.
 495  * @ietf_version_or_minus_one: -1 to ask to connect using the default, latest
 496  *              protocol supported, or the specific protocol ordinal
 497  * @userdata: Pre-allocated user data
 498  *
 499  *      This function creates a connection to a remote server
 500  */
 501
 502 LWS_VISIBLE struct lws *
 503 lws_client_connect_extended(struct lws_context *context, const char *address,
 504                             int port, int ssl_connection, const char *path,
 505                             const char *host, const char *origin,
 506                             const char *protocol, int ietf_version_or_minus_one,
 507                             void *userdata)
 508 {
 509         struct lws_client_connect_info i;
 510
 511         memset(&i, 0, sizeof(i));
 512
 513         i.context = context;
 514         i.address = address;
 515         i.port = port;
 516         i.ssl_connection = ssl_connection;
 517         i.path = path;
 518         i.host = host;
 519         i.origin = origin;
 520         i.protocol = protocol;
 521         i.ietf_version_or_minus_one = ietf_version_or_minus_one;
 522         i.userdata = userdata;
 523
 524         return lws_client_connect_via_info(&i);
 525 }
 526 /**
 527  * lws_client_connect_info() - Connect to another websocket server
 528  *                              DEPRECATED use lws_client_connect_via_info
 529  * @context:    Websocket context
 530  * @address:    Remote server address, eg, "myserver.com"
 531  * @port:       Port to connect to on the remote server, eg, 80
 532  * @ssl_connection:     0 = ws://, 1 = wss:// encrypted, 2 = wss:// allow self
 533  *                      signed certs
 534  * @path:       Websocket path on server
 535  * @host:       Hostname on server
 536  * @origin:     Socket origin name
 537  * @protocol:   Comma-separated list of protocols being asked for from
 538  *              the server, or just one.  The server will pick the one it
 539  *              likes best.  If you don't want to specify a protocol, which is
 540  *              legal, use NULL here.
 541  * @ietf_version_or_minus_one: -1 to ask to connect using the default, latest
 542  *              protocol supported, or the specific protocol ordinal
 543  *
 544  *      This function creates a connection to a remote server
 545  */
 546
 547
 548 LWS_VISIBLE struct lws *
 549 lws_client_connect(struct lws_context *context, const char *address,
 550                             int port, int ssl_connection, const char *path,
 551                             const char *host, const char *origin,
 552                             const char *protocol, int ietf_version_or_minus_one)
 553 {
 554         struct lws_client_connect_info i;
 555
 556         memset(&i, 0, sizeof(i));
 557
 558         i.context = context;
 559         i.address = address;
 560         i.port = port;
 561         i.ssl_connection = ssl_connection;
 562         i.path = path;
 563         i.host = host;
 564         i.origin = origin;
 565         i.protocol = protocol;
 566         i.ietf_version_or_minus_one = ietf_version_or_minus_one;
 567         i.userdata = NULL;
 568
 569         return lws_client_connect_via_info(&i);
 570 }
 571