res/res_pjsip_transport_websocket.c

   1 /*
   2  * Asterisk -- An open source telephony toolkit.
   3  *
   4  * Copyright (C) 2013, Digium, Inc.
   5  *
   6  * Jason Parker <jparker@digium.com>
   7  *
   8  * See http://www.asterisk.org for more information about
   9  * the Asterisk project. Please do not directly contact
  10  * any of the maintainers of this project for assistance;
  11  * the project provides a web site, mailing lists and IRC
  12  * channels for your use.
  13  *
  14  * This program is free software, distributed under the terms of
  15  * the GNU General Public License Version 2. See the LICENSE file
  16  * at the top of the source tree.
  17  */
  18
  19 /*!
  20  * \brief WebSocket transport module
  21  */
  22
  23 /*** MODULEINFO
  24         <depend>pjproject</depend>
  25         <depend>res_pjsip</depend>
  26         <depend>res_http_websocket</depend>
  27         <support_level>core</support_level>
  28  ***/
  29
  30 #include "asterisk.h"
  31
  32 #include <pjsip.h>
  33 #include <pjsip_ua.h>
  34
  35 #include "asterisk/module.h"
  36 #include "asterisk/http_websocket.h"
  37 #include "asterisk/res_pjsip.h"
  38 #include "asterisk/res_pjsip_session.h"
  39 #include "asterisk/taskprocessor.h"
  40
  41 static int transport_type_ws;
  42 static int transport_type_wss;
  43
  44 /*!
  45  * \brief Wrapper for pjsip_transport, for storing the WebSocket session
  46  */
  47 struct ws_transport {
  48         pjsip_transport transport;
  49         pjsip_rx_data rdata;
  50         struct ast_websocket *ws_session;
  51 };
  52
  53 /*!
  54  * \brief Send a message over the WebSocket connection.
  55  *
  56  * Called by pjsip transport manager.
  57  */
  58 static pj_status_t ws_send_msg(pjsip_transport *transport,
  59                             pjsip_tx_data *tdata,
  60                             const pj_sockaddr_t *rem_addr,
  61                             int addr_len,
  62                             void *token,
  63                             pjsip_transport_callback callback)
  64 {
  65         struct ws_transport *wstransport = (struct ws_transport *)transport;
  66
  67         if (ast_websocket_write(wstransport->ws_session, AST_WEBSOCKET_OPCODE_TEXT, tdata->buf.start, (int)(tdata->buf.cur - tdata->buf.start))) {
  68                 return PJ_EUNKNOWN;
  69         }
  70
  71         return PJ_SUCCESS;
  72 }
  73
  74 /*!
  75  * \brief Destroy the pjsip transport.
  76  *
  77  * Called by pjsip transport manager.
  78  */
  79 static pj_status_t ws_destroy(pjsip_transport *transport)
  80 {
  81         struct ws_transport *wstransport = (struct ws_transport *)transport;
  82
  83         if (wstransport->transport.ref_cnt) {
  84                 pj_atomic_destroy(wstransport->transport.ref_cnt);
  85         }
  86
  87         if (wstransport->transport.lock) {
  88                 pj_lock_destroy(wstransport->transport.lock);
  89         }
  90
  91         pjsip_endpt_release_pool(wstransport->transport.endpt, wstransport->transport.pool);
  92
  93         return PJ_SUCCESS;
  94 }
  95
  96 static int transport_shutdown(void *data)
  97 {
  98         pjsip_transport *transport = data;
  99
 100         pjsip_transport_shutdown(transport);
 101         return 0;
 102 }
 103
 104 struct transport_create_data {
 105         struct ws_transport *transport;
 106         struct ast_websocket *ws_session;
 107 };
 108
 109 /*!
 110  * \brief Create a pjsip transport.
 111  */
 112 static int transport_create(void *data)
 113 {
 114         struct transport_create_data *create_data = data;
 115         struct ws_transport *newtransport;
 116
 117         pjsip_endpoint *endpt = ast_sip_get_pjsip_endpoint();
 118         struct pjsip_tpmgr *tpmgr = pjsip_endpt_get_tpmgr(endpt);
 119
 120         pj_pool_t *pool;
 121
 122         pj_str_t buf;
 123
 124         if (!(pool = pjsip_endpt_create_pool(endpt, "ws", 512, 512))) {
 125                 ast_log(LOG_ERROR, "Failed to allocate WebSocket endpoint pool.\n");
 126                 return -1;
 127         }
 128
 129         if (!(newtransport = PJ_POOL_ZALLOC_T(pool, struct ws_transport))) {
 130                 ast_log(LOG_ERROR, "Failed to allocate WebSocket transport.\n");
 131                 pjsip_endpt_release_pool(endpt, pool);
 132                 return -1;
 133         }
 134
 135         newtransport->ws_session = create_data->ws_session;
 136
 137         pj_atomic_create(pool, 0, &newtransport->transport.ref_cnt);
 138         pj_lock_create_recursive_mutex(pool, pool->obj_name, &newtransport->transport.lock);
 139
 140         newtransport->transport.pool = pool;
 141         pj_sockaddr_parse(pj_AF_UNSPEC(), 0, pj_cstr(&buf, ast_sockaddr_stringify(ast_websocket_remote_address(newtransport->ws_session))), &newtransport->transport.key.rem_addr);
 142         newtransport->transport.key.rem_addr.addr.sa_family = pj_AF_INET();
 143         newtransport->transport.key.type = ast_websocket_is_secure(newtransport->ws_session) ? transport_type_wss : transport_type_ws;
 144
 145         newtransport->transport.addr_len = pj_sockaddr_get_len(&newtransport->transport.key.rem_addr);
 146
 147         pj_sockaddr_cp(&newtransport->transport.local_addr, &newtransport->transport.key.rem_addr);
 148
 149         newtransport->transport.local_name.host.ptr = (char *)pj_pool_alloc(pool, newtransport->transport.addr_len+4);
 150         pj_sockaddr_print(&newtransport->transport.key.rem_addr, newtransport->transport.local_name.host.ptr, newtransport->transport.addr_len+4, 0);
 151         newtransport->transport.local_name.host.slen = pj_ansi_strlen(newtransport->transport.local_name.host.ptr);
 152         newtransport->transport.local_name.port = pj_sockaddr_get_port(&newtransport->transport.key.rem_addr);
 153
 154         newtransport->transport.type_name = (char *)pjsip_transport_get_type_name(newtransport->transport.key.type);
 155         newtransport->transport.flag = pjsip_transport_get_flag_from_type((pjsip_transport_type_e)newtransport->transport.key.type);
 156         newtransport->transport.info = (char *)pj_pool_alloc(newtransport->transport.pool, 64);
 157
 158         newtransport->transport.endpt = endpt;
 159         newtransport->transport.tpmgr = tpmgr;
 160         newtransport->transport.send_msg = &ws_send_msg;
 161         newtransport->transport.destroy = &ws_destroy;
 162
 163         pjsip_transport_register(newtransport->transport.tpmgr, (pjsip_transport *)newtransport);
 164
 165         create_data->transport = newtransport;
 166         return 0;
 167 }
 168
 169 struct transport_read_data {
 170         struct ws_transport *transport;
 171         char *payload;
 172         uint64_t payload_len;
 173 };
 174
 175 /*!
 176  * \brief Pass WebSocket data into pjsip transport manager.
 177  */
 178 static int transport_read(void *data)
 179 {
 180         struct transport_read_data *read_data = data;
 181         struct ws_transport *newtransport = read_data->transport;
 182         struct ast_websocket *session = newtransport->ws_session;
 183
 184         pjsip_rx_data *rdata = &newtransport->rdata;
 185         int recvd;
 186         pj_str_t buf;
 187
 188         rdata->tp_info.pool = newtransport->transport.pool;
 189         rdata->tp_info.transport = &newtransport->transport;
 190
 191         pj_gettimeofday(&rdata->pkt_info.timestamp);
 192
 193         pj_memcpy(rdata->pkt_info.packet, read_data->payload, sizeof(rdata->pkt_info.packet));
 194         rdata->pkt_info.len = read_data->payload_len;
 195         rdata->pkt_info.zero = 0;
 196
 197         pj_sockaddr_parse(pj_AF_UNSPEC(), 0, pj_cstr(&buf, ast_sockaddr_stringify(ast_websocket_remote_address(session))), &rdata->pkt_info.src_addr);
 198         rdata->pkt_info.src_addr.addr.sa_family = pj_AF_INET();
 199
 200         rdata->pkt_info.src_addr_len = sizeof(rdata->pkt_info.src_addr);
 201
 202         pj_ansi_strcpy(rdata->pkt_info.src_name, ast_sockaddr_stringify_host(ast_websocket_remote_address(session)));
 203         rdata->pkt_info.src_port = ast_sockaddr_port(ast_websocket_remote_address(session));
 204
 205         recvd = pjsip_tpmgr_receive_packet(rdata->tp_info.transport->tpmgr, rdata);
 206
 207         return (read_data->payload_len == recvd) ? 0 : -1;
 208 }
 209
 210 /*!
 211  \brief WebSocket connection handler.
 212  */
 213 static void websocket_cb(struct ast_websocket *session, struct ast_variable *parameters, struct ast_variable *headers)
 214 {
 215         struct ast_taskprocessor *serializer = NULL;
 216         struct transport_create_data create_data;
 217         struct ws_transport *transport = NULL;
 218         struct transport_read_data read_data;
 219
 220         if (ast_websocket_set_nonblock(session)) {
 221                 ast_websocket_unref(session);
 222                 return;
 223         }
 224
 225         if (!(serializer = ast_sip_create_serializer())) {
 226                 ast_websocket_unref(session);
 227                 return;
 228         }
 229
 230         create_data.ws_session = session;
 231
 232         if (ast_sip_push_task_synchronous(serializer, transport_create, &create_data)) {
 233                 ast_log(LOG_ERROR, "Could not create WebSocket transport.\n");
 234                 ast_websocket_unref(session);
 235                 return;
 236         }
 237
 238         transport = create_data.transport;
 239         read_data.transport = transport;
 240
 241         while (ast_wait_for_input(ast_websocket_fd(session), -1) > 0) {
 242                 enum ast_websocket_opcode opcode;
 243                 int fragmented;
 244
 245                 if (ast_websocket_read(session, &read_data.payload, &read_data.payload_len, &opcode, &fragmented)) {
 246                         break;
 247                 }
 248
 249                 if (opcode == AST_WEBSOCKET_OPCODE_TEXT || opcode == AST_WEBSOCKET_OPCODE_BINARY) {
 250                         ast_sip_push_task_synchronous(serializer, transport_read, &read_data);
 251                 } else if (opcode == AST_WEBSOCKET_OPCODE_CLOSE) {
 252                         break;
 253                 }
 254         }
 255
 256         ast_sip_push_task_synchronous(serializer, transport_shutdown, transport);
 257
 258         ast_taskprocessor_unreference(serializer);
 259         ast_websocket_unref(session);
 260 }
 261
 262 /*!
 263  * \brief Store the transport a message came in on, so it can be used for outbound messages to that contact.
 264  */
 265 static pj_bool_t websocket_on_rx_msg(pjsip_rx_data *rdata)
 266 {
 267         pjsip_contact_hdr *contact;
 268
 269         long type = rdata->tp_info.transport->key.type;
 270
 271         if (type != (long)transport_type_ws && type != (long)transport_type_wss) {
 272                 return PJ_FALSE;
 273         }
 274
 275         if ((contact = pjsip_msg_find_hdr(rdata->msg_info.msg, PJSIP_H_CONTACT, NULL)) &&
 276                 (PJSIP_URI_SCHEME_IS_SIP(contact->uri) || PJSIP_URI_SCHEME_IS_SIPS(contact->uri))) {
 277                 pjsip_sip_uri *uri = pjsip_uri_get_uri(contact->uri);
 278
 279                 pj_cstr(&uri->host, rdata->pkt_info.src_name);
 280                 uri->port = rdata->pkt_info.src_port;
 281         }
 282
 283         rdata->msg_info.via->rport_param = 0;
 284
 285         return PJ_FALSE;
 286 }
 287
 288 static pjsip_module websocket_module = {
 289         .name = { "WebSocket Transport Module", 26 },
 290         .id = -1,
 291         .priority = PJSIP_MOD_PRIORITY_TRANSPORT_LAYER,
 292         .on_rx_request = websocket_on_rx_msg,
 293 };
 294
 295 static int load_module(void)
 296 {
 297         pjsip_transport_register_type(PJSIP_TRANSPORT_RELIABLE, "WS", 5060, &transport_type_ws);
 298         pjsip_transport_register_type(PJSIP_TRANSPORT_RELIABLE, "WSS", 5060, &transport_type_wss);
 299
 300         if (ast_sip_register_service(&websocket_module) != PJ_SUCCESS) {
 301                 return AST_MODULE_LOAD_DECLINE;
 302         }
 303
 304         if (ast_websocket_add_protocol("sip", websocket_cb)) {
 305                 ast_sip_unregister_service(&websocket_module);
 306                 return AST_MODULE_LOAD_DECLINE;
 307         }
 308
 309         return AST_MODULE_LOAD_SUCCESS;
 310 }
 311
 312 static int unload_module(void)
 313 {
 314         ast_sip_unregister_service(&websocket_module);
 315         ast_websocket_remove_protocol("sip", websocket_cb);
 316
 317         return 0;
 318 }
 319
 320 AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_LOAD_ORDER, "PJSIP WebSocket Transport Support",
 321                 .load = load_module,
 322                 .unload = unload_module,
 323                 .load_pri = AST_MODPRI_APP_DEPEND,
 324            );