/* * libwebsockets - small server side websockets and web server implementation * * Copyright (C) 2010 Andy Green * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation: * version 2.1 of the License. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, * MA 02110-1301 USA */ #include "private-libwebsockets.h" #ifdef WIN32 #include #include #else #ifdef LWS_BUILTIN_GETIFADDRS #include #else #include #endif #include #include #include #endif #ifdef LWS_OPENSSL_SUPPORT int openssl_websocket_private_data_index; #endif #ifdef __MINGW32__ #include "../win32port/win32helpers/websock-w32.c" #else #ifdef __MINGW64__ #include "../win32port/win32helpers/websock-w32.c" #endif #endif static int log_level = LLL_ERR | LLL_WARN; static void lwsl_emit_stderr(const char *line); static void (*lwsl_emit)(const char *line) = lwsl_emit_stderr; static const char *log_level_names[] = { "ERR", "WARN", "INFO", "DEBUG", "PARSER", "HEADER", "EXTENSION", "CLIENT", }; int insert_wsi_socket_into_fds(struct libwebsocket_context *context, struct libwebsocket *wsi) { if (context->fds_count >= context->max_fds) { lwsl_err("Reached limit of fds tracking (%d)\n", context->max_fds); return 1; } if (wsi->sock > context->max_fds) { lwsl_err("Socket fd %d is beyond what we can index (%d)\n", wsi->sock, context->max_fds); return 1; } assert(wsi); assert(wsi->sock); lwsl_info("insert_wsi_socket_into_fds: wsi=%p, sock=%d, fds pos=%d\n", wsi, wsi->sock, context->fds_count); context->lws_lookup[wsi->sock] = wsi; wsi->position_in_fds_table = context->fds_count; context->fds[context->fds_count].fd = wsi->sock; context->fds[context->fds_count].events = POLLIN; context->fds[context->fds_count++].revents = 0; /* external POLL support via protocol 0 */ context->protocols[0].callback(context, wsi, LWS_CALLBACK_ADD_POLL_FD, (void *)(long)wsi->sock, NULL, POLLIN); return 0; } static int remove_wsi_socket_from_fds(struct libwebsocket_context *context, struct libwebsocket *wsi) { int m; if (!--context->fds_count) goto do_ext; if (wsi->sock > context->max_fds) { lwsl_err("Socket fd %d is beyond what we can index (%d)\n", wsi->sock, context->max_fds); return 1; } lwsl_info("remove_wsi_socket_from_fds: wsi=%p, sock=%d, fds pos=%d\n", wsi, wsi->sock, wsi->position_in_fds_table); m = wsi->position_in_fds_table; /* replace the contents for this */ /* have the last guy take up the vacant slot */ context->fds[m] = context->fds[context->fds_count]; /* vacant fds slot filled with end one */ /* end guy's fds_lookup entry remains unchanged (still same fd pointing to same wsi) */ /* end guy's "position in fds table" changed */ context->lws_lookup[context->fds[context->fds_count].fd]->position_in_fds_table = m; /* deletion guy's lws_lookup entry needs nuking */ context->lws_lookup[wsi->sock] = NULL; /* no WSI for the socket of the wsi being removed*/ wsi->position_in_fds_table = -1; /* removed wsi has no position any more */ do_ext: /* remove also from external POLL support via protocol 0 */ if (wsi->sock) context->protocols[0].callback(context, wsi, LWS_CALLBACK_DEL_POLL_FD, (void *)(long)wsi->sock, NULL, 0); return 0; } void libwebsocket_close_and_free_session(struct libwebsocket_context *context, struct libwebsocket *wsi, enum lws_close_status reason) { int n; int old_state; unsigned char buf[LWS_SEND_BUFFER_PRE_PADDING + 2 + LWS_SEND_BUFFER_POST_PADDING]; int ret; int m; struct lws_tokens eff_buf; struct libwebsocket_extension *ext; if (!wsi) return; old_state = wsi->state; if (old_state == WSI_STATE_DEAD_SOCKET) return; wsi->close_reason = reason; /* * are his extensions okay with him closing? Eg he might be a mux * parent and just his ch1 aspect is closing? */ for (n = 0; n < wsi->count_active_extensions; n++) { if (!wsi->active_extensions[n]->callback) continue; m = wsi->active_extensions[n]->callback(context, wsi->active_extensions[n], wsi, LWS_EXT_CALLBACK_CHECK_OK_TO_REALLY_CLOSE, wsi->active_extensions_user[n], NULL, 0); /* * if somebody vetoed actually closing him at this time.... * up to the extension to track the attempted close, let's * just bail */ if (m) { lwsl_ext("extension vetoed close\n"); return; } } /* * flush any tx pending from extensions, since we may send close packet * if there are problems with send, just nuke the connection */ ret = 1; while (ret == 1) { /* default to nobody has more to spill */ ret = 0; eff_buf.token = NULL; eff_buf.token_len = 0; /* show every extension the new incoming data */ for (n = 0; n < wsi->count_active_extensions; n++) { m = wsi->active_extensions[n]->callback( wsi->protocol->owning_server, wsi->active_extensions[n], wsi, LWS_EXT_CALLBACK_FLUSH_PENDING_TX, wsi->active_extensions_user[n], &eff_buf, 0); if (m < 0) { lwsl_ext("Extension reports fatal error\n"); goto just_kill_connection; } if (m) /* * at least one extension told us he has more * to spill, so we will go around again after */ ret = 1; } /* assuming they left us something to send, send it */ if (eff_buf.token_len) if (lws_issue_raw(wsi, (unsigned char *)eff_buf.token, eff_buf.token_len)) { lwsl_debug("close: sending final extension spill had problems\n"); goto just_kill_connection; } } /* * signal we are closing, libsocket_write will * add any necessary version-specific stuff. If the write fails, * no worries we are closing anyway. If we didn't initiate this * close, then our state has been changed to * WSI_STATE_RETURNED_CLOSE_ALREADY and we will skip this. * * Likewise if it's a second call to close this connection after we * sent the close indication to the peer already, we are in state * WSI_STATE_AWAITING_CLOSE_ACK and will skip doing this a second time. */ if (old_state == WSI_STATE_ESTABLISHED && reason != LWS_CLOSE_STATUS_NOSTATUS) { lwsl_debug("sending close indication...\n"); n = libwebsocket_write(wsi, &buf[LWS_SEND_BUFFER_PRE_PADDING], 0, LWS_WRITE_CLOSE); if (!n) { /* * we have sent a nice protocol level indication we * now wish to close, we should not send anything more */ wsi->state = WSI_STATE_AWAITING_CLOSE_ACK; /* and we should wait for a reply for a bit out of politeness */ libwebsocket_set_timeout(wsi, PENDING_TIMEOUT_CLOSE_ACK, 1); lwsl_debug("sent close indication, awaiting ack\n"); return; } lwsl_info("close: sending the close packet failed, hanging up\n"); /* else, the send failed and we should just hang up */ } just_kill_connection: lwsl_debug("libwebsocket_close_and_free_session: just_kill_connection\n"); /* * we won't be servicing or receiving anything further from this guy * delete socket from the internal poll list if still present */ remove_wsi_socket_from_fds(context, wsi); wsi->state = WSI_STATE_DEAD_SOCKET; /* tell the user it's all over for this guy */ if (wsi->protocol && wsi->protocol->callback && ((old_state == WSI_STATE_ESTABLISHED) || (old_state == WSI_STATE_RETURNED_CLOSE_ALREADY) || (old_state == WSI_STATE_AWAITING_CLOSE_ACK))) { lwsl_debug("calling back CLOSED\n"); wsi->protocol->callback(context, wsi, LWS_CALLBACK_CLOSED, wsi->user_space, NULL, 0); } else lwsl_debug("not calling back closed, old_state=%d\n", old_state); /* deallocate any active extension contexts */ for (n = 0; n < wsi->count_active_extensions; n++) { if (!wsi->active_extensions[n]->callback) continue; wsi->active_extensions[n]->callback(context, wsi->active_extensions[n], wsi, LWS_EXT_CALLBACK_DESTROY, wsi->active_extensions_user[n], NULL, 0); free(wsi->active_extensions_user[n]); } /* * inform all extensions in case they tracked this guy out of band * even though not active on him specifically */ ext = context->extensions; while (ext && ext->callback) { ext->callback(context, ext, wsi, LWS_EXT_CALLBACK_DESTROY_ANY_WSI_CLOSING, NULL, NULL, 0); ext++; } /* free up his parsing allocations */ for (n = 0; n < WSI_TOKEN_COUNT; n++) if (wsi->utf8_token[n].token) free(wsi->utf8_token[n].token); #ifndef LWS_NO_CLIENT if (wsi->c_address) free(wsi->c_address); #endif if (wsi->rxflow_buffer) free(wsi->rxflow_buffer); /* lwsl_info("closing fd=%d\n", wsi->sock); */ #ifdef LWS_OPENSSL_SUPPORT if (wsi->ssl) { n = SSL_get_fd(wsi->ssl); SSL_shutdown(wsi->ssl); compatible_close(n); SSL_free(wsi->ssl); } else { #endif if (wsi->sock) { n = shutdown(wsi->sock, SHUT_RDWR); if (n) lwsl_debug("closing: shutdown returned %d\n", errno); n = compatible_close(wsi->sock); if (n) lwsl_debug("closing: close returned %d\n", errno); } #ifdef LWS_OPENSSL_SUPPORT } #endif if (wsi->protocol && wsi->protocol->per_session_data_size && wsi->user_space) /* user code may own */ free(wsi->user_space); free(wsi); } /** * libwebsockets_hangup_on_client() - Server calls to terminate client * connection * @context: libwebsockets context * @fd: Connection socket descriptor */ void libwebsockets_hangup_on_client(struct libwebsocket_context *context, int fd) { struct libwebsocket *wsi = context->lws_lookup[fd]; if (wsi) { libwebsocket_close_and_free_session(context, wsi, LWS_CLOSE_STATUS_NOSTATUS); } else close(fd); } /** * libwebsockets_get_peer_addresses() - Get client address information * @fd: Connection socket descriptor * @name: Buffer to take client address name * @name_len: Length of client address name buffer * @rip: Buffer to take client address IP qotted quad * @rip_len: Length of client address IP buffer * * This function fills in @name and @rip with the name and IP of * the client connected with socket descriptor @fd. Names may be * truncated if there is not enough room. If either cannot be * determined, they will be returned as valid zero-length strings. */ void libwebsockets_get_peer_addresses(int fd, char *name, int name_len, char *rip, int rip_len) { unsigned int len; struct sockaddr_in sin; struct hostent *host; struct hostent *host1; char ip[128]; unsigned char *p; int n; #ifdef AF_LOCAL struct sockaddr_un *un; #endif rip[0] = '\0'; name[0] = '\0'; len = sizeof sin; if (getpeername(fd, (struct sockaddr *) &sin, &len) < 0) { perror("getpeername"); return; } host = gethostbyaddr((char *) &sin.sin_addr, sizeof sin.sin_addr, AF_INET); if (host == NULL) { perror("gethostbyaddr"); return; } strncpy(name, host->h_name, name_len); name[name_len - 1] = '\0'; host1 = gethostbyname(host->h_name); if (host1 == NULL) return; p = (unsigned char *)host1; n = 0; while (p != NULL) { p = (unsigned char *)host1->h_addr_list[n++]; if (p == NULL) continue; if ((host1->h_addrtype != AF_INET) #ifdef AF_LOCAL && (host1->h_addrtype != AF_LOCAL) #endif ) continue; if (host1->h_addrtype == AF_INET) sprintf(ip, "%u.%u.%u.%u", p[0], p[1], p[2], p[3]); #ifdef AF_LOCAL else { un = (struct sockaddr_un *)p; strncpy(ip, un->sun_path, sizeof(ip) - 1); ip[sizeof(ip) - 1] = '\0'; } #endif p = NULL; strncpy(rip, ip, rip_len); rip[rip_len - 1] = '\0'; } } int libwebsockets_get_random(struct libwebsocket_context *context, void *buf, int len) { int n; char *p = (char *)buf; #ifdef WIN32 for (n = 0; n < len; n++) p[n] = (unsigned char)rand(); #else n = read(context->fd_random, p, len); #endif return n; } unsigned char * libwebsockets_SHA1(const unsigned char *d, size_t n, unsigned char *md) { return SHA1(d, n, md); } int lws_send_pipe_choked(struct libwebsocket *wsi) { struct pollfd fds; fds.fd = wsi->sock; fds.events = POLLOUT; fds.revents = 0; if (poll(&fds, 1, 0) != 1) return 1; if ((fds.revents & POLLOUT) == 0) return 1; /* okay to send another packet without blocking */ return 0; } int lws_handle_POLLOUT_event(struct libwebsocket_context *context, struct libwebsocket *wsi, struct pollfd *pollfd) { struct lws_tokens eff_buf; int n; int ret; int m; int handled = 0; for (n = 0; n < wsi->count_active_extensions; n++) { if (!wsi->active_extensions[n]->callback) continue; m = wsi->active_extensions[n]->callback(context, wsi->active_extensions[n], wsi, LWS_EXT_CALLBACK_IS_WRITEABLE, wsi->active_extensions_user[n], NULL, 0); if (m > handled) handled = m; } if (handled == 1) goto notify_action; if (!wsi->extension_data_pending || handled == 2) goto user_service; /* * check in on the active extensions, see if they * had pending stuff to spill... they need to get the * first look-in otherwise sequence will be disordered * * NULL, zero-length eff_buf means just spill pending */ ret = 1; while (ret == 1) { /* default to nobody has more to spill */ ret = 0; eff_buf.token = NULL; eff_buf.token_len = 0; /* give every extension a chance to spill */ for (n = 0; n < wsi->count_active_extensions; n++) { m = wsi->active_extensions[n]->callback( wsi->protocol->owning_server, wsi->active_extensions[n], wsi, LWS_EXT_CALLBACK_PACKET_TX_PRESEND, wsi->active_extensions_user[n], &eff_buf, 0); if (m < 0) { lwsl_err("ext reports fatal error\n"); return -1; } if (m) /* * at least one extension told us he has more * to spill, so we will go around again after */ ret = 1; } /* assuming they gave us something to send, send it */ if (eff_buf.token_len) { if (lws_issue_raw(wsi, (unsigned char *)eff_buf.token, eff_buf.token_len)) return -1; } else continue; /* no extension has more to spill */ if (!ret) continue; /* * There's more to spill from an extension, but we just sent * something... did that leave the pipe choked? */ if (!lws_send_pipe_choked(wsi)) /* no we could add more */ continue; lwsl_info("choked in POLLOUT service\n"); /* * Yes, he's choked. Leave the POLLOUT masked on so we will * come back here when he is unchoked. Don't call the user * callback to enforce ordering of spilling, he'll get called * when we come back here and there's nothing more to spill. */ return 0; } wsi->extension_data_pending = 0; user_service: /* one shot */ if (pollfd) { pollfd->events &= ~POLLOUT; /* external POLL support via protocol 0 */ context->protocols[0].callback(context, wsi, LWS_CALLBACK_CLEAR_MODE_POLL_FD, (void *)(long)wsi->sock, NULL, POLLOUT); } notify_action: if (wsi->mode == LWS_CONNMODE_WS_CLIENT) n = LWS_CALLBACK_CLIENT_WRITEABLE; else n = LWS_CALLBACK_SERVER_WRITEABLE; user_callback_handle_rxflow(wsi->protocol->callback, context, wsi, (enum libwebsocket_callback_reasons) n, wsi->user_space, NULL, 0); return 0; } void libwebsocket_service_timeout_check(struct libwebsocket_context *context, struct libwebsocket *wsi, unsigned int sec) { int n; /* * if extensions want in on it (eg, we are a mux parent) * give them a chance to service child timeouts */ for (n = 0; n < wsi->count_active_extensions; n++) wsi->active_extensions[n]->callback( context, wsi->active_extensions[n], wsi, LWS_EXT_CALLBACK_1HZ, wsi->active_extensions_user[n], NULL, sec); if (!wsi->pending_timeout) return; /* * if we went beyond the allowed time, kill the * connection */ if (sec > wsi->pending_timeout_limit) { lwsl_info("TIMEDOUT WAITING\n"); libwebsocket_close_and_free_session(context, wsi, LWS_CLOSE_STATUS_NOSTATUS); } } /** * libwebsocket_service_fd() - Service polled socket with something waiting * @context: Websocket context * @pollfd: The pollfd entry describing the socket fd and which events * happened. * * This function closes any active connections and then frees the * context. After calling this, any further use of the context is * undefined. */ int libwebsocket_service_fd(struct libwebsocket_context *context, struct pollfd *pollfd) { struct libwebsocket *wsi; unsigned char buf[LWS_SEND_BUFFER_PRE_PADDING + 1 + MAX_BROADCAST_PAYLOAD + LWS_SEND_BUFFER_POST_PADDING]; int n; int m; struct timeval tv; int more = 1; struct lws_tokens eff_buf; #ifndef LWS_NO_CLIENT extern int lws_client_socket_service(struct libwebsocket_context *context, struct libwebsocket *wsi, struct pollfd *pollfd); #endif #ifndef LWS_NO_SERVER extern int lws_server_socket_service(struct libwebsocket_context *context, struct libwebsocket *wsi, struct pollfd *pollfd); #endif /* * you can call us with pollfd = NULL to just allow the once-per-second * global timeout checks; if less than a second since the last check * it returns immediately then. */ gettimeofday(&tv, NULL); if (context->last_timeout_check_s != tv.tv_sec) { context->last_timeout_check_s = tv.tv_sec; /* global timeout check once per second */ for (n = 0; n < context->fds_count; n++) { struct libwebsocket *new_wsi = context->lws_lookup[context->fds[n].fd]; if (!new_wsi) continue; libwebsocket_service_timeout_check(context, new_wsi, tv.tv_sec); } } /* just here for timeout management? */ if (pollfd == NULL) return 0; /* no, here to service a socket descriptor */ /* * deal with listen service piggybacking * every listen_service_modulo services of other fds, we * sneak one in to service the listen socket if there's anything waiting * * To handle connection storms, as found in ab, if we previously saw a * pending connection here, it causes us to check again next time. */ if (context->listen_service_fd && pollfd->fd != context->listen_service_fd) { context->listen_service_count++; if (context->listen_service_extraseen || context->listen_service_count == context->listen_service_modulo) { context->listen_service_count = 0; m = 1; if (context->listen_service_extraseen > 5) m = 2; while (m--) { /* even with extpoll, we prepared this internal fds for listen */ n = poll(&context->fds[0], 1, 0); if (n > 0) { /* there's a connection waiting for us */ libwebsocket_service_fd(context, &context->fds[0]); context->listen_service_extraseen++; } else { if (context->listen_service_extraseen) context->listen_service_extraseen--; break; } } } } /* okay, what we came here to do... */ wsi = context->lws_lookup[pollfd->fd]; if (wsi == NULL) { if (pollfd->fd > 11) lwsl_err("unexpected NULL wsi fd=%d fds_count=%d\n", pollfd->fd, context->fds_count); return 0; } switch (wsi->mode) { #ifndef LWS_NO_SERVER case LWS_CONNMODE_HTTP_SERVING: case LWS_CONNMODE_SERVER_LISTENER: case LWS_CONNMODE_BROADCAST_PROXY_LISTENER: case LWS_CONNMODE_BROADCAST_PROXY: return lws_server_socket_service(context, wsi, pollfd); #endif case LWS_CONNMODE_WS_SERVING: case LWS_CONNMODE_WS_CLIENT: /* handle session socket closed */ if (pollfd->revents & (POLLERR | POLLHUP)) { lwsl_debug("Session Socket %p (fd=%d) dead\n", (void *)wsi, pollfd->fd); libwebsocket_close_and_free_session(context, wsi, LWS_CLOSE_STATUS_NOSTATUS); return 0; } /* the guy requested a callback when it was OK to write */ if ((pollfd->revents & POLLOUT) && wsi->state == WSI_STATE_ESTABLISHED) if (lws_handle_POLLOUT_event(context, wsi, pollfd) < 0) { libwebsocket_close_and_free_session( context, wsi, LWS_CLOSE_STATUS_NORMAL); return 0; } /* any incoming data ready? */ if (!(pollfd->revents & POLLIN)) break; #ifdef LWS_OPENSSL_SUPPORT read_pending: if (wsi->ssl) eff_buf.token_len = SSL_read(wsi->ssl, buf, sizeof buf); else #endif eff_buf.token_len = recv(pollfd->fd, buf, sizeof buf, 0); if (eff_buf.token_len < 0) { lwsl_debug("Socket read returned %d\n", eff_buf.token_len); if (errno != EINTR && errno != EAGAIN) libwebsocket_close_and_free_session(context, wsi, LWS_CLOSE_STATUS_NOSTATUS); return 0; } if (!eff_buf.token_len) { libwebsocket_close_and_free_session(context, wsi, LWS_CLOSE_STATUS_NOSTATUS); return 0; } /* * give any active extensions a chance to munge the buffer * before parse. We pass in a pointer to an lws_tokens struct * prepared with the default buffer and content length that's in * there. Rather than rewrite the default buffer, extensions * that expect to grow the buffer can adapt .token to * point to their own per-connection buffer in the extension * user allocation. By default with no extensions or no * extension callback handling, just the normal input buffer is * used then so it is efficient. */ eff_buf.token = (char *)buf; more = 1; while (more) { more = 0; for (n = 0; n < wsi->count_active_extensions; n++) { m = wsi->active_extensions[n]->callback(context, wsi->active_extensions[n], wsi, LWS_EXT_CALLBACK_PACKET_RX_PREPARSE, wsi->active_extensions_user[n], &eff_buf, 0); if (m < 0) { lwsl_ext( "Extension reports fatal error\n"); libwebsocket_close_and_free_session( context, wsi, LWS_CLOSE_STATUS_NOSTATUS); return 0; } if (m) more = 1; } /* service incoming data */ if (eff_buf.token_len) { n = libwebsocket_read(context, wsi, (unsigned char *)eff_buf.token, eff_buf.token_len); if (n < 0) /* we closed wsi */ return 0; } eff_buf.token = NULL; eff_buf.token_len = 0; } #ifdef LWS_OPENSSL_SUPPORT if (wsi->ssl && SSL_pending(wsi->ssl)) goto read_pending; #endif break; default: #ifdef LWS_NO_CLIENT break; #else return lws_client_socket_service(context, wsi, pollfd); #endif } return 0; } /** * libwebsocket_context_destroy() - Destroy the websocket context * @context: Websocket context * * This function closes any active connections and then frees the * context. After calling this, any further use of the context is * undefined. */ void libwebsocket_context_destroy(struct libwebsocket_context *context) { int n; int m; struct libwebsocket_extension *ext; for (n = 0; n < context->fds_count; n++) { struct libwebsocket *wsi = context->lws_lookup[context->fds[n].fd]; libwebsocket_close_and_free_session(context, wsi, LWS_CLOSE_STATUS_GOINGAWAY); } /* * give all extensions a chance to clean up any per-context * allocations they might have made */ ext = context->extensions; m = LWS_EXT_CALLBACK_CLIENT_CONTEXT_DESTRUCT; if (context->listen_port) m = LWS_EXT_CALLBACK_SERVER_CONTEXT_DESTRUCT; while (ext && ext->callback) { ext->callback(context, ext, NULL, (enum libwebsocket_extension_callback_reasons)m, NULL, NULL, 0); ext++; } #ifdef WIN32 #else close(context->fd_random); #endif #ifdef LWS_OPENSSL_SUPPORT if (context->ssl_ctx) SSL_CTX_free(context->ssl_ctx); if (context->ssl_client_ctx) SSL_CTX_free(context->ssl_client_ctx); #endif free(context); #ifdef WIN32 WSACleanup(); #endif } LWS_EXTERN void * libwebsocket_context_user(struct libwebsocket_context *context) { return context->user_space; } /** * libwebsocket_service() - Service any pending websocket activity * @context: Websocket context * @timeout_ms: Timeout for poll; 0 means return immediately if nothing needed * service otherwise block and service immediately, returning * after the timeout if nothing needed service. * * This function deals with any pending websocket traffic, for three * kinds of event. It handles these events on both server and client * types of connection the same. * * 1) Accept new connections to our context's server * * 2) Perform pending broadcast writes initiated from other forked * processes (effectively serializing asynchronous broadcasts) * * 3) Call the receive callback for incoming frame data received by * server or client connections. * * You need to call this service function periodically to all the above * functions to happen; if your application is single-threaded you can * just call it in your main event loop. * * Alternatively you can fork a new process that asynchronously handles * calling this service in a loop. In that case you are happy if this * call blocks your thread until it needs to take care of something and * would call it with a large nonzero timeout. Your loop then takes no * CPU while there is nothing happening. * * If you are calling it in a single-threaded app, you don't want it to * wait around blocking other things in your loop from happening, so you * would call it with a timeout_ms of 0, so it returns immediately if * nothing is pending, or as soon as it services whatever was pending. */ int libwebsocket_service(struct libwebsocket_context *context, int timeout_ms) { int n; /* stay dead once we are dead */ if (context == NULL) return 1; /* wait for something to need service */ n = poll(context->fds, context->fds_count, timeout_ms); if (n == 0) /* poll timeout */ return 0; if (n < 0) return -1; /* any socket with events to service? */ for (n = 0; n < context->fds_count; n++) if (context->fds[n].revents) if (libwebsocket_service_fd(context, &context->fds[n]) < 0) return -1; return 0; } int lws_any_extension_handled(struct libwebsocket_context *context, struct libwebsocket *wsi, enum libwebsocket_extension_callback_reasons r, void *v, size_t len) { int n; int handled = 0; /* maybe an extension will take care of it for us */ for (n = 0; n < wsi->count_active_extensions && !handled; n++) { if (!wsi->active_extensions[n]->callback) continue; handled |= wsi->active_extensions[n]->callback(context, wsi->active_extensions[n], wsi, r, wsi->active_extensions_user[n], v, len); } return handled; } void * lws_get_extension_user_matching_ext(struct libwebsocket *wsi, struct libwebsocket_extension *ext) { int n = 0; if (wsi == NULL) return NULL; while (n < wsi->count_active_extensions) { if (wsi->active_extensions[n] != ext) { n++; continue; } return wsi->active_extensions_user[n]; } return NULL; } /** * libwebsocket_callback_on_writable() - Request a callback when this socket * becomes able to be written to without * blocking * * @context: libwebsockets context * @wsi: Websocket connection instance to get callback for */ int libwebsocket_callback_on_writable(struct libwebsocket_context *context, struct libwebsocket *wsi) { int n; int handled = 0; /* maybe an extension will take care of it for us */ for (n = 0; n < wsi->count_active_extensions; n++) { if (!wsi->active_extensions[n]->callback) continue; handled |= wsi->active_extensions[n]->callback(context, wsi->active_extensions[n], wsi, LWS_EXT_CALLBACK_REQUEST_ON_WRITEABLE, wsi->active_extensions_user[n], NULL, 0); } if (handled) return 1; if (wsi->position_in_fds_table < 0) { lwsl_err("libwebsocket_callback_on_writable: " "failed to find socket %d\n", wsi->sock); return -1; } context->fds[wsi->position_in_fds_table].events |= POLLOUT; /* external POLL support via protocol 0 */ context->protocols[0].callback(context, wsi, LWS_CALLBACK_SET_MODE_POLL_FD, (void *)(long)wsi->sock, NULL, POLLOUT); return 1; } /** * libwebsocket_callback_on_writable_all_protocol() - Request a callback for * all connections using the given protocol when it * becomes possible to write to each socket without * blocking in turn. * * @protocol: Protocol whose connections will get callbacks */ int libwebsocket_callback_on_writable_all_protocol( const struct libwebsocket_protocols *protocol) { struct libwebsocket_context *context = protocol->owning_server; int n; struct libwebsocket *wsi; for (n = 0; n < context->fds_count; n++) { wsi = context->lws_lookup[context->fds[n].fd]; if (!wsi) continue; if (wsi->protocol == protocol) libwebsocket_callback_on_writable(context, wsi); } return 0; } /** * libwebsocket_set_timeout() - marks the wsi as subject to a timeout * * You will not need this unless you are doing something special * * @wsi: Websocket connection instance * @reason: timeout reason * @secs: how many seconds */ void libwebsocket_set_timeout(struct libwebsocket *wsi, enum pending_timeout reason, int secs) { struct timeval tv; gettimeofday(&tv, NULL); wsi->pending_timeout_limit = tv.tv_sec + secs; wsi->pending_timeout = reason; } /** * libwebsocket_get_socket_fd() - returns the socket file descriptor * * You will not need this unless you are doing something special * * @wsi: Websocket connection instance */ int libwebsocket_get_socket_fd(struct libwebsocket *wsi) { return wsi->sock; } #ifdef LWS_NO_SERVER int _libwebsocket_rx_flow_control(struct libwebsocket *wsi) { return 0; } #else int _libwebsocket_rx_flow_control(struct libwebsocket *wsi) { struct libwebsocket_context *context = wsi->protocol->owning_server; int n; if (!(wsi->rxflow_change_to & 2)) return 0; wsi->rxflow_change_to &= ~2; lwsl_info("rxflow: wsi %p change_to %d\n", wsi, wsi->rxflow_change_to); /* if we're letting it come again, did we interrupt anything? */ if ((wsi->rxflow_change_to & 1) && wsi->rxflow_buffer) { n = libwebsocket_interpret_incoming_packet(wsi, NULL, 0); if (n < 0) { libwebsocket_close_and_free_session(context, wsi, LWS_CLOSE_STATUS_NOSTATUS); return -1; } if (n) /* oh he stuck again, do nothing */ return 0; } if (wsi->rxflow_change_to & 1) context->fds[wsi->position_in_fds_table].events |= POLLIN; else context->fds[wsi->position_in_fds_table].events &= ~POLLIN; if (wsi->rxflow_change_to & 1) /* external POLL support via protocol 0 */ context->protocols[0].callback(context, wsi, LWS_CALLBACK_SET_MODE_POLL_FD, (void *)(long)wsi->sock, NULL, POLLIN); else /* external POLL support via protocol 0 */ context->protocols[0].callback(context, wsi, LWS_CALLBACK_CLEAR_MODE_POLL_FD, (void *)(long)wsi->sock, NULL, POLLIN); return 1; } #endif /** * libwebsocket_rx_flow_control() - Enable and disable socket servicing for * receieved packets. * * If the output side of a server process becomes choked, this allows flow * control for the input side. * * @wsi: Websocket connection instance to get callback for * @enable: 0 = disable read servicing for this connection, 1 = enable */ int libwebsocket_rx_flow_control(struct libwebsocket *wsi, int enable) { wsi->rxflow_change_to = 2 | !!enable; return 0; } /** * libwebsocket_canonical_hostname() - returns this host's hostname * * This is typically used by client code to fill in the host parameter * when making a client connection. You can only call it after the context * has been created. * * @context: Websocket context */ extern const char * libwebsocket_canonical_hostname(struct libwebsocket_context *context) { return (const char *)context->canonical_hostname; } static void sigpipe_handler(int x) { } #ifdef LWS_OPENSSL_SUPPORT static int OpenSSL_verify_callback(int preverify_ok, X509_STORE_CTX *x509_ctx) { SSL *ssl; int n; struct libwebsocket_context *context; ssl = X509_STORE_CTX_get_ex_data(x509_ctx, SSL_get_ex_data_X509_STORE_CTX_idx()); /* * !!! nasty openssl requires the index to come as a library-scope * static */ context = SSL_get_ex_data(ssl, openssl_websocket_private_data_index); n = context->protocols[0].callback(NULL, NULL, LWS_CALLBACK_OPENSSL_PERFORM_CLIENT_CERT_VERIFICATION, x509_ctx, ssl, preverify_ok); /* convert return code from 0 = OK to 1 = OK */ if (!n) n = 1; else n = 0; return n; } #endif int user_callback_handle_rxflow(callback_function callback_function, struct libwebsocket_context * context, struct libwebsocket *wsi, enum libwebsocket_callback_reasons reason, void *user, void *in, size_t len) { int n; n = callback_function(context, wsi, reason, user, in, len); if (n < 0) return n; _libwebsocket_rx_flow_control(wsi); return 0; } /** * libwebsocket_create_context() - Create the websocket handler * @port: Port to listen on... you can use 0 to suppress listening on * any port, that's what you want if you are not running a * websocket server at all but just using it as a client * @interf: NULL to bind the listen socket to all interfaces, or the * interface name, eg, "eth2" * @protocols: Array of structures listing supported protocols and a protocol- * specific callback for each one. The list is ended with an * entry that has a NULL callback pointer. * It's not const because we write the owning_server member * @extensions: NULL or array of libwebsocket_extension structs listing the * extensions this context supports * @ssl_cert_filepath: If libwebsockets was compiled to use ssl, and you want * to listen using SSL, set to the filepath to fetch the * server cert from, otherwise NULL for unencrypted * @ssl_private_key_filepath: filepath to private key if wanting SSL mode, * else ignored * @ssl_ca_filepath: CA certificate filepath or NULL * @gid: group id to change to after setting listen socket, or -1. * @uid: user id to change to after setting listen socket, or -1. * @options: 0, or LWS_SERVER_OPTION_DEFEAT_CLIENT_MASK * @user: optional user pointer that can be recovered via the context * pointer using libwebsocket_context_user * * This function creates the listening socket and takes care * of all initialization in one step. * * After initialization, it returns a struct libwebsocket_context * that * represents this server. After calling, user code needs to take care * of calling libwebsocket_service() with the context pointer to get the * server's sockets serviced. This can be done in the same process context * or a forked process, or another thread, * * The protocol callback functions are called for a handful of events * including http requests coming in, websocket connections becoming * established, and data arriving; it's also called periodically to allow * async transmission. * * HTTP requests are sent always to the FIRST protocol in @protocol, since * at that time websocket protocol has not been negotiated. Other * protocols after the first one never see any HTTP callack activity. * * The server created is a simple http server by default; part of the * websocket standard is upgrading this http connection to a websocket one. * * This allows the same server to provide files like scripts and favicon / * images or whatever over http and dynamic data over websockets all in * one place; they're all handled in the user callback. */ struct libwebsocket_context * libwebsocket_create_context(int port, const char *interf, struct libwebsocket_protocols *protocols, struct libwebsocket_extension *extensions, const char *ssl_cert_filepath, const char *ssl_private_key_filepath, const char *ssl_ca_filepath, int gid, int uid, unsigned int options, void *user) { int n; int m; int fd; struct sockaddr_in serv_addr, cli_addr; int opt = 1; struct libwebsocket_context *context = NULL; unsigned int slen; char *p; struct libwebsocket *wsi; #ifdef LWS_OPENSSL_SUPPORT SSL_METHOD *method; char ssl_err_buf[512]; #endif lwsl_info("Initial logging level %d\n", log_level); lwsl_info(" LWS_MAX_HEADER_NAME_LENGTH: %u\n", LWS_MAX_HEADER_NAME_LENGTH); lwsl_info(" LWS_MAX_HEADER_LEN: %u\n", LWS_MAX_HEADER_LEN); lwsl_info(" LWS_INITIAL_HDR_ALLOC: %u\n", LWS_INITIAL_HDR_ALLOC); lwsl_info(" LWS_ADDITIONAL_HDR_ALLOC: %u\n", LWS_ADDITIONAL_HDR_ALLOC); lwsl_info(" MAX_USER_RX_BUFFER: %u\n", MAX_USER_RX_BUFFER); lwsl_info(" MAX_BROADCAST_PAYLOAD: %u\n", MAX_BROADCAST_PAYLOAD); lwsl_info(" LWS_MAX_PROTOCOLS: %u\n", LWS_MAX_PROTOCOLS); lwsl_info(" LWS_MAX_EXTENSIONS_ACTIVE: %u\n", LWS_MAX_EXTENSIONS_ACTIVE); lwsl_info(" SPEC_LATEST_SUPPORTED: %u\n", SPEC_LATEST_SUPPORTED); lwsl_info(" AWAITING_TIMEOUT: %u\n", AWAITING_TIMEOUT); lwsl_info(" CIPHERS_LIST_STRING: '%s'\n", CIPHERS_LIST_STRING); lwsl_info(" SYSTEM_RANDOM_FILEPATH: '%s'\n", SYSTEM_RANDOM_FILEPATH); lwsl_info(" LWS_MAX_ZLIB_CONN_BUFFER: %u\n", LWS_MAX_ZLIB_CONN_BUFFER); #ifdef _WIN32 { WORD wVersionRequested; WSADATA wsaData; int err; HMODULE wsdll; /* Use the MAKEWORD(lowbyte, highbyte) macro from Windef.h */ wVersionRequested = MAKEWORD(2, 2); err = WSAStartup(wVersionRequested, &wsaData); if (err != 0) { /* Tell the user that we could not find a usable */ /* Winsock DLL. */ lwsl_err("WSAStartup failed with error: %d\n", err); return NULL; } /* default to a poll() made out of select() */ poll = emulated_poll; /* if windows socket lib available, use his WSAPoll */ wsdll = GetModuleHandle(_T("Ws2_32.dll")); if (wsdll) poll = (PFNWSAPOLL)GetProcAddress(wsdll, "WSAPoll"); } #endif context = (struct libwebsocket_context *) malloc(sizeof(struct libwebsocket_context)); if (!context) { lwsl_err("No memory for websocket context\n"); return NULL; } context->protocols = protocols; context->listen_port = port; context->http_proxy_port = 0; context->http_proxy_address[0] = '\0'; context->options = options; /* to reduce this allocation, */ context->max_fds = getdtablesize(); lwsl_info(" max fd tracked: %u\n", context->max_fds); context->fds = (struct pollfd *)malloc(sizeof(struct pollfd) * context->max_fds); if (context->fds == NULL) { lwsl_err("Unable to allocate fds array for %d connections\n", context->max_fds); free(context); return NULL; } context->lws_lookup = (struct libwebsocket **)malloc(sizeof(struct libwebsocke *) * context->max_fds); if (context->lws_lookup == NULL) { lwsl_err("Unable to allocate lws_lookup array for %d connections\n", context->max_fds); free(context->fds); free(context); return NULL; } context->fds_count = 0; context->extensions = extensions; context->last_timeout_check_s = 0; context->user_space = user; #ifdef WIN32 context->fd_random = 0; #else context->fd_random = open(SYSTEM_RANDOM_FILEPATH, O_RDONLY); if (context->fd_random < 0) { free(context); lwsl_err("Unable to open random device %s %d\n", SYSTEM_RANDOM_FILEPATH, context->fd_random); return NULL; } #endif #ifdef LWS_OPENSSL_SUPPORT context->use_ssl = 0; context->ssl_ctx = NULL; context->ssl_client_ctx = NULL; openssl_websocket_private_data_index = 0; #endif strcpy(context->canonical_hostname, "unknown"); #ifndef LWS_NO_SERVER if (!(options & LWS_SERVER_OPTION_SKIP_SERVER_CANONICAL_NAME)) { struct sockaddr sa; char hostname[1024] = ""; /* find canonical hostname */ hostname[(sizeof hostname) - 1] = '\0'; memset(&sa, 0, sizeof(sa)); sa.sa_family = AF_INET; sa.sa_data[(sizeof sa.sa_data) - 1] = '\0'; gethostname(hostname, (sizeof hostname) - 1); n = 0; if (strlen(hostname) < sizeof(sa.sa_data) - 1) { strcpy(sa.sa_data, hostname); // lwsl_debug("my host name is %s\n", sa.sa_data); n = getnameinfo(&sa, sizeof(sa), hostname, (sizeof hostname) - 1, NULL, 0, 0); } if (!n) { strncpy(context->canonical_hostname, hostname, sizeof context->canonical_hostname - 1); context->canonical_hostname[ sizeof context->canonical_hostname - 1] = '\0'; } else strncpy(context->canonical_hostname, hostname, sizeof context->canonical_hostname - 1); lwsl_info(" canonical_hostname = %s\n", context->canonical_hostname); } #endif /* split the proxy ads:port if given */ p = getenv("http_proxy"); if (p) { strncpy(context->http_proxy_address, p, sizeof context->http_proxy_address - 1); context->http_proxy_address[ sizeof context->http_proxy_address - 1] = '\0'; p = strchr(context->http_proxy_address, ':'); if (p == NULL) { lwsl_err("http_proxy needs to be ads:port\n"); return NULL; } *p = '\0'; context->http_proxy_port = atoi(p + 1); lwsl_info(" Proxy %s:%u\n", context->http_proxy_address, context->http_proxy_port); } #ifndef LWS_NO_SERVER if (port) { #ifdef LWS_OPENSSL_SUPPORT context->use_ssl = ssl_cert_filepath != NULL && ssl_private_key_filepath != NULL; if (context->use_ssl) lwsl_info(" Compiled with SSL support, using it\n"); else lwsl_info(" Compiled with SSL support, not using it\n"); #else if (ssl_cert_filepath != NULL && ssl_private_key_filepath != NULL) { lwsl_info(" Not compiled for OpenSSl support!\n"); return NULL; } lwsl_info(" Compiled without SSL support, " "serving unencrypted\n"); #endif } #endif /* ignore SIGPIPE */ #ifdef WIN32 #else signal(SIGPIPE, sigpipe_handler); #endif #ifdef LWS_OPENSSL_SUPPORT /* basic openssl init */ SSL_library_init(); OpenSSL_add_all_algorithms(); SSL_load_error_strings(); openssl_websocket_private_data_index = SSL_get_ex_new_index(0, "libwebsockets", NULL, NULL, NULL); /* * Firefox insists on SSLv23 not SSLv3 * Konq disables SSLv2 by default now, SSLv23 works */ method = (SSL_METHOD *)SSLv23_server_method(); if (!method) { lwsl_err("problem creating ssl method: %s\n", ERR_error_string(ERR_get_error(), ssl_err_buf)); return NULL; } context->ssl_ctx = SSL_CTX_new(method); /* create context */ if (!context->ssl_ctx) { lwsl_err("problem creating ssl context: %s\n", ERR_error_string(ERR_get_error(), ssl_err_buf)); return NULL; } #ifdef SSL_OP_NO_COMPRESSION SSL_CTX_set_options(context->ssl_ctx, SSL_OP_NO_COMPRESSION); #endif SSL_CTX_set_options(context->ssl_ctx, SSL_OP_CIPHER_SERVER_PREFERENCE); SSL_CTX_set_cipher_list(context->ssl_ctx, CIPHERS_LIST_STRING); #ifndef LWS_NO_CLIENT /* client context */ if (port == CONTEXT_PORT_NO_LISTEN) { method = (SSL_METHOD *)SSLv23_client_method(); if (!method) { lwsl_err("problem creating ssl method: %s\n", ERR_error_string(ERR_get_error(), ssl_err_buf)); return NULL; } /* create context */ context->ssl_client_ctx = SSL_CTX_new(method); if (!context->ssl_client_ctx) { lwsl_err("problem creating ssl context: %s\n", ERR_error_string(ERR_get_error(), ssl_err_buf)); return NULL; } #ifdef SSL_OP_NO_COMPRESSION SSL_CTX_set_options(context->ssl_client_ctx, SSL_OP_NO_COMPRESSION); #endif SSL_CTX_set_options(context->ssl_client_ctx, SSL_OP_CIPHER_SERVER_PREFERENCE); SSL_CTX_set_cipher_list(context->ssl_client_ctx, CIPHERS_LIST_STRING); /* openssl init for cert verification (for client sockets) */ if (!ssl_ca_filepath) { if (!SSL_CTX_load_verify_locations( context->ssl_client_ctx, NULL, LWS_OPENSSL_CLIENT_CERTS)) lwsl_err( "Unable to load SSL Client certs from %s " "(set by --with-client-cert-dir= in configure) -- " " client ssl isn't going to work", LWS_OPENSSL_CLIENT_CERTS); } else if (!SSL_CTX_load_verify_locations( context->ssl_client_ctx, ssl_ca_filepath, NULL)) lwsl_err( "Unable to load SSL Client certs " "file from %s -- client ssl isn't " "going to work", ssl_ca_filepath); /* * callback allowing user code to load extra verification certs * helping the client to verify server identity */ context->protocols[0].callback(context, NULL, LWS_CALLBACK_OPENSSL_LOAD_EXTRA_CLIENT_VERIFY_CERTS, context->ssl_client_ctx, NULL, 0); } #endif /* as a server, are we requiring clients to identify themselves? */ if (options & LWS_SERVER_OPTION_REQUIRE_VALID_OPENSSL_CLIENT_CERT) { /* absolutely require the client cert */ SSL_CTX_set_verify(context->ssl_ctx, SSL_VERIFY_PEER | SSL_VERIFY_FAIL_IF_NO_PEER_CERT, OpenSSL_verify_callback); /* * give user code a chance to load certs into the server * allowing it to verify incoming client certs */ context->protocols[0].callback(context, NULL, LWS_CALLBACK_OPENSSL_LOAD_EXTRA_SERVER_VERIFY_CERTS, context->ssl_ctx, NULL, 0); } if (context->use_ssl) { /* openssl init for server sockets */ /* set the local certificate from CertFile */ n = SSL_CTX_use_certificate_chain_file(context->ssl_ctx, ssl_cert_filepath); if (n != 1) { lwsl_err("problem getting cert '%s': %s\n", ssl_cert_filepath, ERR_error_string(ERR_get_error(), ssl_err_buf)); return NULL; } /* set the private key from KeyFile */ if (SSL_CTX_use_PrivateKey_file(context->ssl_ctx, ssl_private_key_filepath, SSL_FILETYPE_PEM) != 1) { lwsl_err("ssl problem getting key '%s': %s\n", ssl_private_key_filepath, ERR_error_string(ERR_get_error(), ssl_err_buf)); return NULL; } /* verify private key */ if (!SSL_CTX_check_private_key(context->ssl_ctx)) { lwsl_err("Private SSL key doesn't match cert\n"); return NULL; } /* SSL is happy and has a cert it's content with */ } #endif /* selftest */ if (lws_b64_selftest()) return NULL; #ifndef LWS_NO_SERVER /* set up our external listening socket we serve on */ if (port) { extern int interface_to_sa(const char *ifname, struct sockaddr_in *addr, size_t addrlen); int sockfd; sockfd = socket(AF_INET, SOCK_STREAM, 0); if (sockfd < 0) { lwsl_err("ERROR opening socket\n"); return NULL; } /* allow us to restart even if old sockets in TIME_WAIT */ setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, (const void *)&opt, sizeof(opt)); /* Disable Nagle */ opt = 1; setsockopt(sockfd, IPPROTO_TCP, TCP_NODELAY, (const void *)&opt, sizeof(opt)); bzero((char *) &serv_addr, sizeof(serv_addr)); serv_addr.sin_family = AF_INET; if (interf == NULL) serv_addr.sin_addr.s_addr = INADDR_ANY; else interface_to_sa(interf, &serv_addr, sizeof(serv_addr)); serv_addr.sin_port = htons(port); n = bind(sockfd, (struct sockaddr *) &serv_addr, sizeof(serv_addr)); if (n < 0) { lwsl_err("ERROR on binding to port %d (%d %d)\n", port, n, errno); close(sockfd); return NULL; } wsi = (struct libwebsocket *)malloc(sizeof(struct libwebsocket)); if (wsi == NULL) { lwsl_err("Out of mem\n"); close(sockfd); return NULL; } memset(wsi, 0, sizeof (struct libwebsocket)); wsi->sock = sockfd; wsi->count_active_extensions = 0; wsi->mode = LWS_CONNMODE_SERVER_LISTENER; insert_wsi_socket_into_fds(context, wsi); context->listen_service_modulo = LWS_LISTEN_SERVICE_MODULO; context->listen_service_count = 0; context->listen_service_fd = sockfd; listen(sockfd, LWS_SOMAXCONN); lwsl_info(" Listening on port %d\n", port); } #endif /* * drop any root privs for this process * to listen on port < 1023 we would have needed root, but now we are * listening, we don't want the power for anything else */ #ifdef WIN32 #else if (gid != -1) if (setgid(gid)) lwsl_warn("setgid: %s\n", strerror(errno)); if (uid != -1) if (setuid(uid)) lwsl_warn("setuid: %s\n", strerror(errno)); #endif /* set up our internal broadcast trigger sockets per-protocol */ for (context->count_protocols = 0; protocols[context->count_protocols].callback; context->count_protocols++) { lwsl_parser(" Protocol: %s\n", protocols[context->count_protocols].name); protocols[context->count_protocols].owning_server = context; protocols[context->count_protocols].protocol_index = context->count_protocols; fd = socket(AF_INET, SOCK_STREAM, 0); if (fd < 0) { lwsl_err("ERROR opening socket\n"); return NULL; } /* allow us to restart even if old sockets in TIME_WAIT */ setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, (const void *)&opt, sizeof(opt)); bzero((char *) &serv_addr, sizeof(serv_addr)); serv_addr.sin_family = AF_INET; serv_addr.sin_addr.s_addr = inet_addr("127.0.0.1"); serv_addr.sin_port = 0; /* pick the port for us */ n = bind(fd, (struct sockaddr *) &serv_addr, sizeof(serv_addr)); if (n < 0) { lwsl_err("ERROR on binding to port %d (%d %d)\n", port, n, errno); return NULL; } slen = sizeof cli_addr; n = getsockname(fd, (struct sockaddr *)&cli_addr, &slen); if (n < 0) { lwsl_err("getsockname failed\n"); return NULL; } protocols[context->count_protocols].broadcast_socket_port = ntohs(cli_addr.sin_port); listen(fd, 5); lwsl_debug(" Protocol %s broadcast socket %d\n", protocols[context->count_protocols].name, ntohs(cli_addr.sin_port)); /* dummy wsi per broadcast proxy socket */ wsi = (struct libwebsocket *)malloc(sizeof(struct libwebsocket)); if (wsi == NULL) { lwsl_err("Out of mem\n"); close(fd); return NULL; } memset(wsi, 0, sizeof (struct libwebsocket)); wsi->sock = fd; wsi->mode = LWS_CONNMODE_BROADCAST_PROXY_LISTENER; wsi->count_active_extensions = 0; /* note which protocol we are proxying */ wsi->protocol_index_for_broadcast_proxy = context->count_protocols; insert_wsi_socket_into_fds(context, wsi); } /* * give all extensions a chance to create any per-context * allocations they need */ m = LWS_EXT_CALLBACK_CLIENT_CONTEXT_CONSTRUCT; if (port) m = LWS_EXT_CALLBACK_SERVER_CONTEXT_CONSTRUCT; if (extensions) { while (extensions->callback) { lwsl_ext(" Extension: %s\n", extensions->name); extensions->callback(context, extensions, NULL, (enum libwebsocket_extension_callback_reasons)m, NULL, NULL, 0); extensions++; } } return context; } #ifndef LWS_NO_FORK /** * libwebsockets_fork_service_loop() - Optional helper function forks off * a process for the websocket server loop. * You don't have to use this but if not, you * have to make sure you are calling * libwebsocket_service periodically to service * the websocket traffic * @context: server context returned by creation function */ int libwebsockets_fork_service_loop(struct libwebsocket_context *context) { int fd; struct sockaddr_in cli_addr; int n; int p; n = fork(); if (n < 0) return n; if (!n) { /* main process context */ /* * set up the proxy sockets to allow broadcast from * service process context */ for (p = 0; p < context->count_protocols; p++) { fd = socket(AF_INET, SOCK_STREAM, 0); if (fd < 0) { lwsl_err("Unable to create socket\n"); return -1; } cli_addr.sin_family = AF_INET; cli_addr.sin_port = htons( context->protocols[p].broadcast_socket_port); cli_addr.sin_addr.s_addr = inet_addr("127.0.0.1"); n = connect(fd, (struct sockaddr *)&cli_addr, sizeof cli_addr); if (n < 0) { lwsl_err("Unable to connect to " "broadcast socket %d, %s\n", n, strerror(errno)); return -1; } context->protocols[p].broadcast_socket_user_fd = fd; } return 0; } #ifdef HAVE_SYS_PRCTL_H /* we want a SIGHUP when our parent goes down */ prctl(PR_SET_PDEATHSIG, SIGHUP); #endif /* in this forked process, sit and service websocket connections */ while (1) { if (libwebsocket_service(context, 1000)) break; //#ifndef HAVE_SYS_PRCTL_H /* * on systems without prctl() (i.e. anything but linux) we can notice that our * parent is dead if getppid() returns 1. FIXME apparently this is not true for * solaris, could remember ppid right after fork and wait for it to change. */ if (getppid() == 1) break; //#endif } return 1; } #endif /** * libwebsockets_get_protocol() - Returns a protocol pointer from a websocket * connection. * @wsi: pointer to struct websocket you want to know the protocol of * * * This is useful to get the protocol to broadcast back to from inside * the callback. */ const struct libwebsocket_protocols * libwebsockets_get_protocol(struct libwebsocket *wsi) { return wsi->protocol; } /** * libwebsockets_broadcast() - Sends a buffer to the callback for all active * connections of the given protocol. * @protocol: pointer to the protocol you will broadcast to all members of * @buf: buffer containing the data to be broadcase. NOTE: this has to be * allocated with LWS_SEND_BUFFER_PRE_PADDING valid bytes before * the pointer and LWS_SEND_BUFFER_POST_PADDING afterwards in the * case you are calling this function from callback context. * @len: length of payload data in buf, starting from buf. * * This function allows bulk sending of a packet to every connection using * the given protocol. It does not send the data directly; instead it calls * the callback with a reason type of LWS_CALLBACK_BROADCAST. If the callback * wants to actually send the data for that connection, the callback itself * should call libwebsocket_write(). * * libwebsockets_broadcast() can be called from another fork context without * having to take any care about data visibility between the processes, it'll * "just work". */ int libwebsockets_broadcast(const struct libwebsocket_protocols *protocol, unsigned char *buf, size_t len) { struct libwebsocket_context *context = protocol->owning_server; int n; struct libwebsocket *wsi; if (!protocol->broadcast_socket_user_fd) { /* * We are either running unforked / flat, or we are being * called from poll thread context * eg, from a callback. In that case don't use sockets for * broadcast IPC (since we can't open a socket connection to * a socket listening on our own thread) but directly do the * send action. * * Locking is not needed because we are by definition being * called in the poll thread context and are serialized. */ for (n = 0; n < context->fds_count; n++) { wsi = context->lws_lookup[context->fds[n].fd]; if (!wsi) continue; if (wsi->mode != LWS_CONNMODE_WS_SERVING) continue; /* * never broadcast to non-established connections */ if (wsi->state != WSI_STATE_ESTABLISHED) continue; /* only broadcast to guys using * requested protocol */ if (wsi->protocol != protocol) continue; user_callback_handle_rxflow(wsi->protocol->callback, context, wsi, LWS_CALLBACK_BROADCAST, wsi->user_space, buf, len); } return 0; } /* * We're being called from a different process context than the server * loop. Instead of broadcasting directly, we send our * payload on a socket to do the IPC; the server process will serialize * the broadcast action in its main poll() loop. * * There's one broadcast socket listening for each protocol supported * set up when the websocket server initializes */ n = send(protocol->broadcast_socket_user_fd, buf, len, MSG_NOSIGNAL); return n; } int libwebsocket_is_final_fragment(struct libwebsocket *wsi) { return wsi->final; } unsigned char libwebsocket_get_reserved_bits(struct libwebsocket *wsi) { return wsi->rsv; } void * libwebsocket_ensure_user_space(struct libwebsocket *wsi) { /* allocate the per-connection user memory (if any) */ if (wsi->protocol->per_session_data_size && !wsi->user_space) { wsi->user_space = malloc( wsi->protocol->per_session_data_size); if (wsi->user_space == NULL) { lwsl_err("Out of memory for conn user space\n"); return NULL; } memset(wsi->user_space, 0, wsi->protocol->per_session_data_size); } return wsi->user_space; } /** * lws_confirm_legit_wsi: returns nonzero if the wsi looks bad * * @wsi: struct libwebsocket to assess * * Performs consistecy checks on what the wsi claims and what the * polling arrays hold. This'll catch a closed wsi still in use. * Don't try to use on the listen (nonconnection) wsi as it will * fail it. Otherwise 0 return == wsi seems consistent. */ int lws_confirm_legit_wsi(struct libwebsocket *wsi) { struct libwebsocket_context *context; if (!(wsi && wsi->protocol && wsi->protocol->owning_server)) return 1; context = wsi->protocol->owning_server; if (!context) return 2; if (!wsi->position_in_fds_table) return 3; /* position in fds table looks bad */ if (context->fds[wsi->position_in_fds_table].fd != wsi->sock) return 4; /* pollfd entry does not wait on our socket descriptor */ if (context->lws_lookup[wsi->sock] != wsi) return 5; /* lookup table does not agree with wsi */ return 0; } static void lwsl_emit_stderr(int level, const char *line) { char buf[300]; struct timeval tv; int pos = 0; int n; gettimeofday(&tv, NULL); buf[0] = '\0'; for (n = 0; n < LLL_COUNT; n++) if (level == (1 << n)) { pos = sprintf(buf, "[%ld:%04d] %s: ", tv.tv_sec, (int)(tv.tv_usec / 100), log_level_names[n]); break; } fprintf(stderr, "%s%s", buf, line); } void _lws_log(int filter, const char *format, ...) { char buf[256]; va_list ap; if (!(log_level & filter)) return; va_start(ap, format); vsnprintf(buf, (sizeof buf), format, ap); buf[(sizeof buf) - 1] = '\0'; va_end(ap); lwsl_emit(filter, buf); } /** * lws_set_log_level() - Set the logging bitfield * @level: OR together the LLL_ debug contexts you want output from * @log_emit_function: NULL to leave it as it is, or a user-supplied * function to perform log string emission instead of * the default stderr one. * * log level defaults to "err" and "warn" contexts enabled only and * emission on stderr. */ void lws_set_log_level(int level, void (*log_emit_function)(const char *line)) { log_level = level; if (log_emit_function) lwsl_emit = log_emit_function; }