lib/client-handshake.c

   1 #include "private-libwebsockets.h"
   2
   3 struct libwebsocket *libwebsocket_client_connect_2(
   4         struct libwebsocket_context *context,
   5         struct libwebsocket *wsi
   6 ) {
   7         struct libwebsocket_pollfd pfd;
   8 #ifdef LWS_USE_IPV6
   9         struct sockaddr_in6 server_addr6;
  10         struct sockaddr_in6 client_addr6;
  11         struct addrinfo hints, *result;
  12 #endif
  13         struct sockaddr_in server_addr4;
  14         struct sockaddr_in client_addr4;
  15         struct hostent *server_hostent;
  16
  17         struct sockaddr *v;
  18         int n;
  19         int plen = 0;
  20         const char *ads;
  21
  22        lwsl_client("libwebsocket_client_connect_2\n");
  23
  24         /*
  25          * proxy?
  26          */
  27
  28         if (context->http_proxy_port) {
  29                 plen = sprintf((char *)context->service_buffer,
  30                         "CONNECT %s:%u HTTP/1.0\x0d\x0a"
  31                         "User-agent: libwebsockets\x0d\x0a"
  32 /*Proxy-authorization: basic aGVsbG86d29ybGQ= */
  33                         "\x0d\x0a",
  34                         lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_PEER_ADDRESS),
  35                         wsi->u.hdr.ah->c_port);
  36                 ads = context->http_proxy_address;
  37
  38 #ifdef LWS_USE_IPV6
  39                 if (LWS_IPV6_ENABLED(context))
  40                         server_addr6.sin6_port = htons(context->http_proxy_port);
  41                 else
  42 #endif
  43                         server_addr4.sin_port = htons(context->http_proxy_port);
  44
  45         } else {
  46                 ads = lws_hdr_simple_ptr(wsi, _WSI_TOKEN_CLIENT_PEER_ADDRESS);
  47 #ifdef LWS_USE_IPV6
  48                 if (LWS_IPV6_ENABLED(context))
  49                         server_addr6.sin6_port = htons(wsi->u.hdr.ah->c_port);
  50                 else
  51 #endif
  52                         server_addr4.sin_port = htons(wsi->u.hdr.ah->c_port);
  53         }
  54
  55         /*
  56          * prepare the actual connection (to the proxy, if any)
  57          */
  58        lwsl_client("libwebsocket_client_connect_2: address %s\n", ads);
  59
  60 #ifdef LWS_USE_IPV6
  61         if (LWS_IPV6_ENABLED(context)) {
  62                 memset(&hints, 0, sizeof(struct addrinfo));
  63                 n = getaddrinfo(ads, NULL, &hints, &result);
  64                 if (n) {
  65                         lwsl_err("getaddrinfo: %s\n", gai_strerror(n));
  66                         goto oom4;
  67                 }
  68
  69                 server_addr6.sin6_family = AF_INET6;
  70                 switch (result->ai_family) {
  71                 case AF_INET:
  72                         /* map IPv4 to IPv6 */
  73                         bzero((char *)&server_addr6.sin6_addr,
  74                                                 sizeof(struct in6_addr));
  75                         server_addr6.sin6_addr.s6_addr[10] = 0xff;
  76                         server_addr6.sin6_addr.s6_addr[11] = 0xff;
  77                         memcpy(&server_addr6.sin6_addr.s6_addr[12],
  78                                 &((struct sockaddr_in *)result->ai_addr)->sin_addr,
  79                                                         sizeof(struct in_addr));
  80                         break;
  81                 case AF_INET6:
  82                         memcpy(&server_addr6.sin6_addr,
  83                           &((struct sockaddr_in6 *)result->ai_addr)->sin6_addr,
  84                                                 sizeof(struct in6_addr));
  85                         break;
  86                 default:
  87                         lwsl_err("Unknown address family\n");
  88                         freeaddrinfo(result);
  89                         goto oom4;
  90                 }
  91
  92                 freeaddrinfo(result);
  93         } else
  94 #endif
  95         {
  96                 server_hostent = gethostbyname(ads);
  97                 if (!server_hostent) {
  98                         lwsl_err("Unable to get host name from %s\n", ads);
  99                         goto oom4;
 100                 }
 101
 102                 server_addr4.sin_family = AF_INET;
 103                 server_addr4.sin_addr =
 104                                 *((struct in_addr *)server_hostent->h_addr);
 105                 bzero(&server_addr4.sin_zero, 8);
 106         }
 107
 108         if (wsi->sock < 0) {
 109
 110 #ifdef LWS_USE_IPV6
 111                 if (LWS_IPV6_ENABLED(context))
 112                         wsi->sock = socket(AF_INET6, SOCK_STREAM, 0);
 113                 else
 114 #endif
 115                         wsi->sock = socket(AF_INET, SOCK_STREAM, 0);
 116
 117                 if (wsi->sock < 0) {
 118                         lwsl_warn("Unable to open socket\n");
 119                         goto oom4;
 120                 }
 121
 122                 if (lws_plat_set_socket_options(context, wsi->sock)) {
 123                         lwsl_err("Failed to set wsi socket options\n");
 124                         compatible_close(wsi->sock);
 125                         goto oom4;
 126                 }
 127
 128                 wsi->mode = LWS_CONNMODE_WS_CLIENT_WAITING_CONNECT;
 129
 130                 insert_wsi_socket_into_fds(context, wsi);
 131
 132                 libwebsocket_set_timeout(wsi,
 133                         PENDING_TIMEOUT_AWAITING_CONNECT_RESPONSE,
 134                                                               AWAITING_TIMEOUT);
 135 #ifdef LWS_USE_IPV6
 136                 if (LWS_IPV6_ENABLED(context)) {
 137                         v = (struct sockaddr *)&client_addr6;
 138                         n = sizeof(client_addr6);
 139                         bzero((char *)v, n);
 140                         client_addr6.sin6_family = AF_INET6;
 141                 } else
 142 #endif
 143                 {
 144                         v = (struct sockaddr *)&client_addr4;
 145                         n = sizeof(client_addr4);
 146                         bzero((char *)v, n);
 147                         client_addr4.sin_family = AF_INET;
 148                 }
 149
 150                 if (context->iface) {
 151                         if (interface_to_sa(context, context->iface,
 152                                         (struct sockaddr_in *)v, n) < 0) {
 153                                 lwsl_err("Unable to find interface %s\n",
 154                                                                 context->iface);
 155                                 compatible_close(wsi->sock);
 156                                 goto failed;
 157                         }
 158
 159                         if (bind(wsi->sock, v, n) < 0) {
 160                                 lwsl_err("Error binding to interface %s",
 161                                                                 context->iface);
 162                                 compatible_close(wsi->sock);
 163                                 goto failed;
 164                         }
 165                 }
 166         }
 167
 168 #ifdef LWS_USE_IPV6
 169         if (LWS_IPV6_ENABLED(context)) {
 170                 v = (struct sockaddr *)&server_addr6;
 171                 n = sizeof(struct sockaddr_in6);
 172         } else
 173 #endif
 174         {
 175                 v = (struct sockaddr *)&server_addr4;
 176                 n = sizeof(struct sockaddr);
 177         }
 178
 179         if (connect(wsi->sock, v, n) == -1 || LWS_ERRNO == LWS_EISCONN) {
 180
 181                 if (LWS_ERRNO == LWS_EALREADY || LWS_ERRNO == LWS_EINPROGRESS
 182                                               || LWS_ERRNO == LWS_EWOULDBLOCK) {
 183                         lwsl_client("nonblocking connect retry\n");
 184
 185                         /*
 186                          * must do specifically a POLLOUT poll to hear
 187                          * about the connect completion
 188                          */
 189                         if (lws_change_pollfd(wsi, 0, LWS_POLLOUT))
 190                                 goto oom4;
 191
 192                         return wsi;
 193                 }
 194
 195                 if (LWS_ERRNO != LWS_EISCONN) {
 196                         lwsl_debug("Connect failed errno=%d\n", LWS_ERRNO);
 197                         goto failed;
 198                 }
 199         }
 200
 201         lwsl_client("connected\n");
 202
 203         /* we are connected to server, or proxy */
 204
 205         if (context->http_proxy_port) {
 206
 207                 /* OK from now on we talk via the proxy, so connect to that */
 208
 209                 /*
 210                  * (will overwrite existing pointer,
 211                  * leaving old string/frag there but unreferenced)
 212                  */
 213                 if (lws_hdr_simple_create(wsi, _WSI_TOKEN_CLIENT_PEER_ADDRESS,
 214                                                    context->http_proxy_address))
 215                         goto failed;
 216                 wsi->u.hdr.ah->c_port = context->http_proxy_port;
 217
 218                 n = send(wsi->sock, context->service_buffer, plen, MSG_NOSIGNAL);
 219                 if (n < 0) {
 220                         lwsl_debug("ERROR writing to proxy socket\n");
 221                         goto failed;
 222                 }
 223
 224                 libwebsocket_set_timeout(wsi,
 225                         PENDING_TIMEOUT_AWAITING_PROXY_RESPONSE,
 226                                                               AWAITING_TIMEOUT);
 227
 228                 wsi->mode = LWS_CONNMODE_WS_CLIENT_WAITING_PROXY_REPLY;
 229
 230                 return wsi;
 231         }
 232
 233         /*
 234          * provoke service to issue the handshake directly
 235          * we need to do it this way because in the proxy case, this is the
 236          * next state and executed only if and when we get a good proxy
 237          * response inside the state machine... but notice in SSL case this
 238          * may not have sent anything yet with 0 return, and won't until some
 239          * many retries from main loop.  To stop that becoming endless,
 240          * cover with a timeout.
 241          */
 242
 243         libwebsocket_set_timeout(wsi,
 244                 PENDING_TIMEOUT_SENT_CLIENT_HANDSHAKE, AWAITING_TIMEOUT);
 245
 246         wsi->mode = LWS_CONNMODE_WS_CLIENT_ISSUE_HANDSHAKE;
 247         pfd.fd = wsi->sock;
 248         pfd.revents = LWS_POLLIN;
 249
 250         n = libwebsocket_service_fd(context, &pfd);
 251
 252         if (n < 0)
 253                 goto failed;
 254
 255         if (n) /* returns 1 on failure after closing wsi */
 256                 return NULL;
 257
 258         return wsi;
 259
 260 oom4:
 261         free(wsi->u.hdr.ah);
 262         free(wsi);
 263         return NULL;
 264
 265 failed:
 266         libwebsocket_close_and_free_session(context, wsi,
 267                                                      LWS_CLOSE_STATUS_NOSTATUS);
 268         return NULL;
 269 }
 270
 271 /**
 272  * libwebsocket_client_connect() - Connect to another websocket server
 273  * @context:    Websocket context
 274  * @address:    Remote server address, eg, "myserver.com"
 275  * @port:       Port to connect to on the remote server, eg, 80
 276  * @ssl_connection:     0 = ws://, 1 = wss:// encrypted, 2 = wss:// allow self
 277  *                      signed certs
 278  * @path:       Websocket path on server
 279  * @host:       Hostname on server
 280  * @origin:     Socket origin name
 281  * @protocol:   Comma-separated list of protocols being asked for from
 282  *              the server, or just one.  The server will pick the one it
 283  *              likes best.
 284  * @ietf_version_or_minus_one: -1 to ask to connect using the default, latest
 285  *              protocol supported, or the specific protocol ordinal
 286  *
 287  *      This function creates a connection to a remote server
 288  */
 289
 290 LWS_VISIBLE struct libwebsocket *
 291 libwebsocket_client_connect(struct libwebsocket_context *context,
 292                               const char *address,
 293                               int port,
 294                               int ssl_connection,
 295                               const char *path,
 296                               const char *host,
 297                               const char *origin,
 298                               const char *protocol,
 299                               int ietf_version_or_minus_one)
 300 {
 301         struct libwebsocket *wsi;
 302
 303         wsi = (struct libwebsocket *) malloc(sizeof(struct libwebsocket));
 304         if (wsi == NULL)
 305                 goto bail;
 306
 307         memset(wsi, 0, sizeof(*wsi));
 308         wsi->sock = -1;
 309
 310         /* -1 means just use latest supported */
 311
 312         if (ietf_version_or_minus_one == -1)
 313                 ietf_version_or_minus_one = SPEC_LATEST_SUPPORTED;
 314
 315         wsi->ietf_spec_revision = ietf_version_or_minus_one;
 316         wsi->user_space = NULL;
 317         wsi->state = WSI_STATE_CLIENT_UNCONNECTED;
 318         wsi->protocol = NULL;
 319         wsi->pending_timeout = NO_PENDING_TIMEOUT;
 320
 321 #ifdef LWS_OPENSSL_SUPPORT
 322         wsi->use_ssl = ssl_connection;
 323 #else
 324         if (ssl_connection) {
 325                 lwsl_err("libwebsockets not configured for ssl\n");
 326                 goto bail;
 327         }
 328 #endif
 329
 330         if (lws_allocate_header_table(wsi))
 331                 goto bail;
 332
 333         /*
 334          * we're not necessarily in a position to action these right away,
 335          * stash them... we only need during connect phase so u.hdr is fine
 336          */
 337         wsi->u.hdr.ah->c_port = port;
 338         if (lws_hdr_simple_create(wsi, _WSI_TOKEN_CLIENT_PEER_ADDRESS, address))
 339                 goto bail1;
 340
 341         /* these only need u.hdr lifetime as well */
 342
 343         if (lws_hdr_simple_create(wsi, _WSI_TOKEN_CLIENT_URI, path))
 344                 goto bail1;
 345
 346         if (lws_hdr_simple_create(wsi, _WSI_TOKEN_CLIENT_HOST, host))
 347                 goto bail1;
 348
 349         if (origin)
 350                 if (lws_hdr_simple_create(wsi,
 351                                 _WSI_TOKEN_CLIENT_ORIGIN, origin))
 352                         goto bail1;
 353         /*
 354          * this is a list of protocols we tell the server we're okay with
 355          * stash it for later when we compare server response with it
 356          */
 357         if (protocol)
 358                 if (lws_hdr_simple_create(wsi,
 359                                 _WSI_TOKEN_CLIENT_SENT_PROTOCOLS, protocol))
 360                         goto bail1;
 361
 362         wsi->protocol = &context->protocols[0];
 363
 364         /*
 365          * Check with each extension if it is able to route and proxy this
 366          * connection for us.  For example, an extension like x-google-mux
 367          * can handle this and then we don't need an actual socket for this
 368          * connection.
 369          */
 370
 371         if (lws_ext_callback_for_each_extension_type(context, wsi,
 372                         LWS_EXT_CALLBACK_CAN_PROXY_CLIENT_CONNECTION,
 373                                                 (void *)address, port) > 0) {
 374                 lwsl_client("libwebsocket_client_connect: ext handling conn\n");
 375
 376                 libwebsocket_set_timeout(wsi,
 377                         PENDING_TIMEOUT_AWAITING_EXTENSION_CONNECT_RESPONSE,
 378                                                               AWAITING_TIMEOUT);
 379
 380                 wsi->mode = LWS_CONNMODE_WS_CLIENT_WAITING_EXTENSION_CONNECT;
 381                 return wsi;
 382         }
 383         lwsl_client("libwebsocket_client_connect: direct conn\n");
 384
 385        return libwebsocket_client_connect_2(context, wsi);
 386
 387 bail1:
 388         free(wsi->u.hdr.ah);
 389 bail:
 390         free(wsi);
 391
 392         return NULL;
 393 }
 394
 395
 396 /**
 397  * libwebsocket_client_connect_extended() - Connect to another websocket server
 398  * @context:    Websocket context
 399  * @address:    Remote server address, eg, "myserver.com"
 400  * @port:       Port to connect to on the remote server, eg, 80
 401  * @ssl_connection:     0 = ws://, 1 = wss:// encrypted, 2 = wss:// allow self
 402  *                      signed certs
 403  * @path:       Websocket path on server
 404  * @host:       Hostname on server
 405  * @origin:     Socket origin name
 406  * @protocol:   Comma-separated list of protocols being asked for from
 407  *              the server, or just one.  The server will pick the one it
 408  *              likes best.
 409  * @ietf_version_or_minus_one: -1 to ask to connect using the default, latest
 410  *              protocol supported, or the specific protocol ordinal
 411  * @userdata: Pre-allocated user data
 412  *
 413  *      This function creates a connection to a remote server
 414  */
 415
 416 LWS_VISIBLE struct libwebsocket *
 417 libwebsocket_client_connect_extended(struct libwebsocket_context *context,
 418                               const char *address,
 419                               int port,
 420                               int ssl_connection,
 421                               const char *path,
 422                               const char *host,
 423                               const char *origin,
 424                               const char *protocol,
 425                               int ietf_version_or_minus_one,
 426                               void *userdata)
 427 {
 428         struct libwebsocket *ws =
 429                 libwebsocket_client_connect(context, address, port,
 430                         ssl_connection, path, host, origin, protocol,
 431                                                      ietf_version_or_minus_one);
 432
 433         if (ws && !ws->user_space && userdata)
 434                 ws->user_space = userdata ;
 435
 436         return ws ;
 437 }