/* * 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 #else #include #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 /* * In-place str to lower case */ static void strtolower(char *s) { while (*s) { *s = tolower(*s); s++; } } /* file descriptor hash management */ struct libwebsocket * wsi_from_fd(struct libwebsocket_context *context, int fd) { int h = LWS_FD_HASH(fd); int n = 0; for (n = 0; n < context->fd_hashtable[h].length; n++) if (context->fd_hashtable[h].wsi[n]->sock == fd) return context->fd_hashtable[h].wsi[n]; return NULL; } int insert_wsi(struct libwebsocket_context *context, struct libwebsocket *wsi) { int h = LWS_FD_HASH(wsi->sock); if (context->fd_hashtable[h].length == MAX_CLIENTS - 1) { fprintf(stderr, "hash table overflow\n"); return 1; } context->fd_hashtable[h].wsi[context->fd_hashtable[h].length++] = wsi; return 0; } int delete_from_fd(struct libwebsocket_context *context, int fd) { int h = LWS_FD_HASH(fd); int n = 0; for (n = 0; n < context->fd_hashtable[h].length; n++) if (context->fd_hashtable[h].wsi[n]->sock == fd) { while (n < context->fd_hashtable[h].length) { context->fd_hashtable[h].wsi[n] = context->fd_hashtable[h].wsi[n + 1]; n++; } context->fd_hashtable[h].length--; return 0; } fprintf(stderr, "Failed to find fd %d requested for " "delete in hashtable\n", fd); return 1; } #ifdef LWS_OPENSSL_SUPPORT static void libwebsockets_decode_ssl_error(void) { char buf[256]; u_long err; while ((err = ERR_get_error()) != 0) { ERR_error_string_n(err, buf, sizeof(buf)); fprintf(stderr, "*** %s\n", buf); } } #endif static int interface_to_sa(const char *ifname, struct sockaddr_in *addr, size_t addrlen) { int rc = -1; #ifdef WIN32 /* TODO */ #else struct ifaddrs *ifr; struct ifaddrs *ifc; struct sockaddr_in *sin; getifaddrs(&ifr); for (ifc = ifr; ifc != NULL; ifc = ifc->ifa_next) { if (strcmp(ifc->ifa_name, ifname)) continue; if (ifc->ifa_addr == NULL) continue; sin = (struct sockaddr_in *)ifc->ifa_addr; if (sin->sin_family != AF_INET) continue; memcpy(addr, sin, addrlen); rc = 0; } freeifaddrs(ifr); #endif return rc; } 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) { debug("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) { fprintf(stderr, "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)) 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) { 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 */ libwebsocket_set_timeout(wsi, PENDING_TIMEOUT_CLOSE_ACK, 5); debug("sent close indication, awaiting ack\n"); return; } /* else, the send failed and we should just hang up */ } just_kill_connection: debug("libwebsocket_close_and_free_session: just_kill_connection\n"); /* * we won't be servicing or receiving anything further from this guy * remove this fd from wsi mapping hashtable */ if (wsi->sock) delete_from_fd(context, wsi->sock); /* delete it from the internal poll list if still present */ for (n = 0; n < context->fds_count; n++) { if (context->fds[n].fd != wsi->sock) continue; while (n < context->fds_count - 1) { context->fds[n] = context->fds[n + 1]; n++; } context->fds_count--; /* we only have to deal with one */ n = context->fds_count; } /* 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); 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))) { debug("calling back CLOSED\n"); wsi->protocol->callback(context, wsi, LWS_CALLBACK_CLOSED, wsi->user_space, NULL, 0); } else 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); if (wsi->c_address) free(wsi->c_address); /* fprintf(stderr, "closing fd=%d\n", wsi->sock); */ #ifdef LWS_OPENSSL_SUPPORT if (wsi->ssl) { n = SSL_get_fd(wsi->ssl); SSL_shutdown(wsi->ssl); #ifdef WIN32 closesocket(n); #else close(n); #endif SSL_free(wsi->ssl); } else { #endif shutdown(wsi->sock, SHUT_RDWR); #ifdef WIN32 if (wsi->sock) closesocket(wsi->sock); #else if (wsi->sock) close(wsi->sock); #endif #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 = wsi_from_fd(context, fd); if (wsi == NULL) return; libwebsocket_close_and_free_session(context, wsi, LWS_CLOSE_STATUS_NOSTATUS); } /** * 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; struct sockaddr_un *un; 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 = 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); } void libwebsockets_00_spaceout(char *key, int spaces, int seed) { char *p; key++; while (spaces--) { if (*key && (seed & 1)) key++; seed >>= 1; p = key + strlen(key); while (p >= key) { p[1] = p[0]; p--; } *key++ = ' '; } } void libwebsockets_00_spam(char *key, int count, int seed) { char *p; key++; while (count--) { if (*key && (seed & 1)) key++; seed >>= 1; p = key + strlen(key); while (p >= key) { p[1] = p[0]; p--; } *key++ = 0x21 + ((seed & 0xffff) % 15); /* 4 would use it up too fast.. not like it matters */ seed >>= 1; } } 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) { fprintf(stderr, "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; debug("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; wsi->protocol->callback(context, wsi, 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) { debug("TIMEDOUT WAITING\n"); libwebsocket_close_and_free_session(context, wsi, LWS_CLOSE_STATUS_NOSTATUS); } } struct libwebsocket * libwebsocket_create_new_server_wsi(struct libwebsocket_context *context) { struct libwebsocket *new_wsi; int n; new_wsi = malloc(sizeof(struct libwebsocket)); if (new_wsi == NULL) { fprintf(stderr, "Out of memory for new connection\n"); return NULL; } memset(new_wsi, 0, sizeof(struct libwebsocket)); new_wsi->count_active_extensions = 0; new_wsi->pending_timeout = NO_PENDING_TIMEOUT; /* intialize the instance struct */ new_wsi->state = WSI_STATE_HTTP; new_wsi->name_buffer_pos = 0; new_wsi->mode = LWS_CONNMODE_WS_SERVING; for (n = 0; n < WSI_TOKEN_COUNT; n++) { new_wsi->utf8_token[n].token = NULL; new_wsi->utf8_token[n].token_len = 0; } /* * these can only be set once the protocol is known * we set an unestablished connection's protocol pointer * to the start of the supported list, so it can look * for matching ones during the handshake */ new_wsi->protocol = context->protocols; new_wsi->user_space = NULL; /* * Default protocol is 76 / 00 * After 76, there's a header specified to inform which * draft the client wants, when that's seen we modify * the individual connection's spec revision accordingly */ new_wsi->ietf_spec_revision = 0; return new_wsi; } char * libwebsockets_generate_client_handshake(struct libwebsocket_context *context, struct libwebsocket *wsi, char *pkt) { char hash[20]; char *p = pkt; int n; struct libwebsocket_extension *ext; struct libwebsocket_extension *ext1; int ext_count = 0; unsigned char buf[LWS_SEND_BUFFER_PRE_PADDING + 1 + MAX_BROADCAST_PAYLOAD + LWS_SEND_BUFFER_POST_PADDING]; static const char magic_websocket_guid[] = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11"; /* * create the random key */ n = libwebsockets_get_random(context, hash, 16); if (n != 16) { fprintf(stderr, "Unable to read from random dev %s\n", SYSTEM_RANDOM_FILEPATH); free(wsi->c_path); free(wsi->c_host); if (wsi->c_origin) free(wsi->c_origin); if (wsi->c_protocol) free(wsi->c_protocol); libwebsocket_close_and_free_session(context, wsi, LWS_CLOSE_STATUS_NOSTATUS); return NULL; } lws_b64_encode_string(hash, 16, wsi->key_b64, sizeof wsi->key_b64); /* * 00 example client handshake * * GET /socket.io/websocket HTTP/1.1 * Upgrade: WebSocket * Connection: Upgrade * Host: 127.0.0.1:9999 * Origin: http://127.0.0.1 * Sec-WebSocket-Key1: 1 0 2#0W 9 89 7 92 ^ * Sec-WebSocket-Key2: 7 7Y 4328 B2v[8(z1 * Cookie: socketio=websocket * * (Á®Ä0¶†≥ * * 04 example client handshake * * GET /chat HTTP/1.1 * Host: server.example.com * Upgrade: websocket * Connection: Upgrade * Sec-WebSocket-Key: dGhlIHNhbXBsZSBub25jZQ== * Sec-WebSocket-Origin: http://example.com * Sec-WebSocket-Protocol: chat, superchat * Sec-WebSocket-Version: 4 */ p += sprintf(p, "GET %s HTTP/1.1\x0d\x0a", wsi->c_path); if (wsi->ietf_spec_revision == 0) { unsigned char spaces_1, spaces_2; unsigned int max_1, max_2; unsigned int num_1, num_2; unsigned long product_1, product_2; char key_1[40]; char key_2[40]; unsigned int seed; unsigned int count; char challenge[16]; libwebsockets_get_random(context, &spaces_1, sizeof(char)); libwebsockets_get_random(context, &spaces_2, sizeof(char)); spaces_1 = (spaces_1 % 12) + 1; spaces_2 = (spaces_2 % 12) + 1; max_1 = 4294967295 / spaces_1; max_2 = 4294967295 / spaces_2; libwebsockets_get_random(context, &num_1, sizeof(int)); libwebsockets_get_random(context, &num_2, sizeof(int)); num_1 = (num_1 % max_1); num_2 = (num_2 % max_2); challenge[0] = num_1 >> 24; challenge[1] = num_1 >> 16; challenge[2] = num_1 >> 8; challenge[3] = num_1; challenge[4] = num_2 >> 24; challenge[5] = num_2 >> 16; challenge[6] = num_2 >> 8; challenge[7] = num_2; product_1 = num_1 * spaces_1; product_2 = num_2 * spaces_2; sprintf(key_1, "%lu", product_1); sprintf(key_2, "%lu", product_2); libwebsockets_get_random(context, &seed, sizeof(int)); libwebsockets_get_random(context, &count, sizeof(int)); libwebsockets_00_spam(key_1, (count % 12) + 1, seed); libwebsockets_get_random(context, &seed, sizeof(int)); libwebsockets_get_random(context, &count, sizeof(int)); libwebsockets_00_spam(key_2, (count % 12) + 1, seed); libwebsockets_get_random(context, &seed, sizeof(int)); libwebsockets_00_spaceout(key_1, spaces_1, seed); libwebsockets_00_spaceout(key_2, spaces_2, seed >> 16); p += sprintf(p, "Upgrade: WebSocket\x0d\x0a" "Connection: Upgrade\x0d\x0aHost: %s\x0d\x0a", wsi->c_host); if (wsi->c_origin) p += sprintf(p, "Origin: %s\x0d\x0a", wsi->c_origin); if (wsi->c_protocol) p += sprintf(p, "Sec-WebSocket-Protocol: %s" "\x0d\x0a", wsi->c_protocol); p += sprintf(p, "Sec-WebSocket-Key1: %s\x0d\x0a", key_1); p += sprintf(p, "Sec-WebSocket-Key2: %s\x0d\x0a", key_2); /* give userland a chance to append, eg, cookies */ context->protocols[0].callback(context, wsi, LWS_CALLBACK_CLIENT_APPEND_HANDSHAKE_HEADER, NULL, &p, (pkt + sizeof(pkt)) - p - 12); p += sprintf(p, "\x0d\x0a"); if (libwebsockets_get_random(context, p, 8) != 8) return NULL; memcpy(&challenge[8], p, 8); p += 8; /* precompute what we want to see from the server */ MD5((unsigned char *)challenge, 16, (unsigned char *)wsi->initial_handshake_hash_base64); goto issue_hdr; } p += sprintf(p, "Host: %s\x0d\x0a", wsi->c_host); p += sprintf(p, "Upgrade: websocket\x0d\x0a"); p += sprintf(p, "Connection: Upgrade\x0d\x0a" "Sec-WebSocket-Key: "); strcpy(p, wsi->key_b64); p += strlen(wsi->key_b64); p += sprintf(p, "\x0d\x0a"); if (wsi->c_origin) p += sprintf(p, "Sec-WebSocket-Origin: %s\x0d\x0a", wsi->c_origin); if (wsi->c_protocol) p += sprintf(p, "Sec-WebSocket-Protocol: %s\x0d\x0a", wsi->c_protocol); /* tell the server what extensions we could support */ p += sprintf(p, "Sec-WebSocket-Extensions: "); ext = context->extensions; while (ext && ext->callback) { n = 0; ext1 = context->extensions; while (ext1 && ext1->callback) { n |= ext1->callback(context, ext1, wsi, LWS_EXT_CALLBACK_CHECK_OK_TO_PROPOSE_EXTENSION, NULL, (char *)ext->name, 0); ext1++; } if (n) { /* an extension vetos us */ debug("ext %s vetoed\n", (char *)ext->name); ext++; continue; } n = context->protocols[0].callback(context, wsi, LWS_CALLBACK_CLIENT_CONFIRM_EXTENSION_SUPPORTED, wsi->user_space, (char *)ext->name, 0); /* * zero return from callback means * go ahead and allow the extension, * it's what we get if the callback is * unhandled */ if (n) { ext++; continue; } /* apply it */ if (ext_count) *p++ = ','; p += sprintf(p, "%s", ext->name); ext_count++; ext++; } p += sprintf(p, "\x0d\x0a"); if (wsi->ietf_spec_revision) p += sprintf(p, "Sec-WebSocket-Version: %d\x0d\x0a", wsi->ietf_spec_revision); /* give userland a chance to append, eg, cookies */ context->protocols[0].callback(context, wsi, LWS_CALLBACK_CLIENT_APPEND_HANDSHAKE_HEADER, NULL, &p, (pkt + sizeof(pkt)) - p - 12); p += sprintf(p, "\x0d\x0a"); /* prepare the expected server accept response */ strcpy((char *)buf, wsi->key_b64); strcpy((char *)&buf[strlen((char *)buf)], magic_websocket_guid); SHA1(buf, strlen((char *)buf), (unsigned char *)hash); lws_b64_encode_string(hash, 20, wsi->initial_handshake_hash_base64, sizeof wsi->initial_handshake_hash_base64); issue_hdr: #if 0 puts(pkt); #endif /* done with these now */ free(wsi->c_path); free(wsi->c_host); if (wsi->c_origin) free(wsi->c_origin); return p; } int lws_client_interpret_server_handshake(struct libwebsocket_context *context, struct libwebsocket *wsi) { unsigned char buf[LWS_SEND_BUFFER_PRE_PADDING + 1 + MAX_BROADCAST_PAYLOAD + LWS_SEND_BUFFER_POST_PADDING]; char pkt[1024]; char *p = &pkt[0]; const char *pc; const char *c; int more = 1; int okay = 0; char ext_name[128]; struct libwebsocket_extension *ext; void *v; int len = 0; int n; static const char magic_websocket_04_masking_guid[] = "61AC5F19-FBBA-4540-B96F-6561F1AB40A8"; /* * 00 / 76 --> * * HTTP/1.1 101 WebSocket Protocol Handshake * Upgrade: WebSocket * Connection: Upgrade * Sec-WebSocket-Origin: http://127.0.0.1 * Sec-WebSocket-Location: ws://127.0.0.1:9999/socket.io/websocket * * xxxxxxxxxxxxxxxx */ if (wsi->ietf_spec_revision == 0) { if (!wsi->utf8_token[WSI_TOKEN_HTTP].token_len || !wsi->utf8_token[WSI_TOKEN_UPGRADE].token_len || !wsi->utf8_token[WSI_TOKEN_CHALLENGE].token_len || !wsi->utf8_token[WSI_TOKEN_CONNECTION].token_len || (!wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len && wsi->c_protocol != NULL)) { debug("libwebsocket_client_handshake " "missing required header(s)\n"); pkt[len] = '\0'; debug("%s", pkt); goto bail3; } strtolower(wsi->utf8_token[WSI_TOKEN_HTTP].token); if (strncmp(wsi->utf8_token[WSI_TOKEN_HTTP].token, "101", 3)) { fprintf(stderr, "libwebsocket_client_handshake " "server sent bad HTTP response '%s'\n", wsi->utf8_token[WSI_TOKEN_HTTP].token); goto bail3; } if (wsi->utf8_token[WSI_TOKEN_CHALLENGE].token_len < 16) { fprintf(stderr, "libwebsocket_client_handshake " "challenge reply too short %d\n", wsi->utf8_token[ WSI_TOKEN_CHALLENGE].token_len); pkt[len] = '\0'; debug("%s", pkt); goto bail3; } goto select_protocol; } /* * well, what the server sent looked reasonable for syntax. * Now let's confirm it sent all the necessary headers */ #if 0 fprintf(stderr, "WSI_TOKEN_HTTP: %d\n", wsi->utf8_token[WSI_TOKEN_HTTP].token_len); fprintf(stderr, "WSI_TOKEN_UPGRADE: %d\n", wsi->utf8_token[WSI_TOKEN_UPGRADE].token_len); fprintf(stderr, "WSI_TOKEN_CONNECTION: %d\n", wsi->utf8_token[WSI_TOKEN_CONNECTION].token_len); fprintf(stderr, "WSI_TOKEN_ACCEPT: %d\n", wsi->utf8_token[WSI_TOKEN_ACCEPT].token_len); fprintf(stderr, "WSI_TOKEN_NONCE: %d\n", wsi->utf8_token[WSI_TOKEN_NONCE].token_len); fprintf(stderr, "WSI_TOKEN_PROTOCOL: %d\n", wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len); #endif if (!wsi->utf8_token[WSI_TOKEN_HTTP].token_len || !wsi->utf8_token[WSI_TOKEN_UPGRADE].token_len || !wsi->utf8_token[WSI_TOKEN_CONNECTION].token_len || !wsi->utf8_token[WSI_TOKEN_ACCEPT].token_len || (!wsi->utf8_token[WSI_TOKEN_NONCE].token_len && wsi->ietf_spec_revision == 4) || (!wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len && wsi->c_protocol != NULL)) { debug("libwebsocket_client_handshake " "missing required header(s)\n"); pkt[len] = '\0'; debug("%s", pkt); goto bail3; } /* * Everything seems to be there, now take a closer look at what * is in each header */ strtolower(wsi->utf8_token[WSI_TOKEN_HTTP].token); if (strncmp(wsi->utf8_token[WSI_TOKEN_HTTP].token, "101", 3)) { fprintf(stderr, "libwebsocket_client_handshake " "server sent bad HTTP response '%s'\n", wsi->utf8_token[WSI_TOKEN_HTTP].token); goto bail3; } strtolower(wsi->utf8_token[WSI_TOKEN_UPGRADE].token); if (strcmp(wsi->utf8_token[WSI_TOKEN_UPGRADE].token, "websocket")) { fprintf(stderr, "libwebsocket_client_handshake server " "sent bad Upgrade header '%s'\n", wsi->utf8_token[WSI_TOKEN_UPGRADE].token); goto bail3; } strtolower(wsi->utf8_token[WSI_TOKEN_CONNECTION].token); if (strcmp(wsi->utf8_token[WSI_TOKEN_CONNECTION].token, "upgrade")) { fprintf(stderr, "libwebsocket_client_handshake server " "sent bad Connection hdr '%s'\n", wsi->utf8_token[WSI_TOKEN_CONNECTION].token); goto bail3; } select_protocol: pc = wsi->c_protocol; if (pc == NULL) fprintf(stderr, "lws_client_interpret_server_handshake: " "NULL c_protocol\n"); else debug("lws_client_interpret_server_handshake: " "cPprotocol='%s'\n", pc); /* * confirm the protocol the server wants to talk was in the list * of protocols we offered */ if (!wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len) { fprintf(stderr, "lws_client_interpret_server_handshake " "WSI_TOKEN_PROTOCOL is null\n"); /* * no protocol name to work from, * default to first protocol */ wsi->protocol = &context->protocols[0]; wsi->c_callback = wsi->protocol->callback; free(wsi->c_protocol); goto check_accept; } while (*pc && !okay) { if ((!strncmp(pc, wsi->utf8_token[WSI_TOKEN_PROTOCOL].token, wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len)) && (pc[wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len] == ',' || pc[wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len] == '\0')) { okay = 1; continue; } while (*pc && *pc != ',') pc++; while (*pc && *pc != ' ') pc++; } /* done with him now */ if (wsi->c_protocol) free(wsi->c_protocol); if (!okay) { fprintf(stderr, "libwebsocket_client_handshake server " "sent bad protocol '%s'\n", wsi->utf8_token[WSI_TOKEN_PROTOCOL].token); goto bail2; } /* * identify the selected protocol struct and set it */ n = 0; wsi->protocol = NULL; while (context->protocols[n].callback && !wsi->protocol) { /* Stop after finding first one?? */ if (strcmp(wsi->utf8_token[WSI_TOKEN_PROTOCOL].token, context->protocols[n].name) == 0) { wsi->protocol = &context->protocols[n]; wsi->c_callback = wsi->protocol->callback; } n++; } if (wsi->protocol == NULL) { fprintf(stderr, "libwebsocket_client_handshake server " "requested protocol '%s', which we " "said we supported but we don't!\n", wsi->utf8_token[WSI_TOKEN_PROTOCOL].token); goto bail2; } /* instantiate the accepted extensions */ if (!wsi->utf8_token[WSI_TOKEN_EXTENSIONS].token_len) { debug("no client extenstions allowed by server\n"); goto check_accept; } /* * break down the list of server accepted extensions * and go through matching them or identifying bogons */ c = wsi->utf8_token[WSI_TOKEN_EXTENSIONS].token; n = 0; while (more) { if (*c && (*c != ',' && *c != ' ' && *c != '\t')) { ext_name[n] = *c++; if (n < sizeof(ext_name) - 1) n++; continue; } ext_name[n] = '\0'; if (!*c) more = 0; else { c++; if (!n) continue; } /* check we actually support it */ debug("checking client ext %s\n", ext_name); n = 0; ext = wsi->protocol->owning_server->extensions; while (ext && ext->callback) { if (strcmp(ext_name, ext->name)) { ext++; continue; } n = 1; debug("instantiating client ext %s\n", ext_name); /* instantiate the extension on this conn */ wsi->active_extensions_user[ wsi->count_active_extensions] = malloc(ext->per_session_data_size); memset(wsi->active_extensions_user[ wsi->count_active_extensions], 0, ext->per_session_data_size); wsi->active_extensions[ wsi->count_active_extensions] = ext; /* allow him to construct his context */ ext->callback(wsi->protocol->owning_server, ext, wsi, LWS_EXT_CALLBACK_CLIENT_CONSTRUCT, wsi->active_extensions_user[ wsi->count_active_extensions], NULL, 0); wsi->count_active_extensions++; ext++; } if (n == 0) { fprintf(stderr, "Server said we should use" "an unknown extension '%s'!\n", ext_name); goto bail2; } n = 0; } check_accept: if (wsi->ietf_spec_revision == 0) { if (memcmp(wsi->initial_handshake_hash_base64, wsi->utf8_token[WSI_TOKEN_CHALLENGE].token, 16)) { fprintf(stderr, "libwebsocket_client_handshake " "failed 00 challenge compare\n"); pkt[len] = '\0'; fprintf(stderr, "%s", pkt); goto bail2; } goto accept_ok; } /* * Confirm his accept token is the one we precomputed */ if (strcmp(wsi->utf8_token[WSI_TOKEN_ACCEPT].token, wsi->initial_handshake_hash_base64)) { fprintf(stderr, "libwebsocket_client_handshake server " "sent bad ACCEPT '%s' vs computed '%s'\n", wsi->utf8_token[WSI_TOKEN_ACCEPT].token, wsi->initial_handshake_hash_base64); goto bail2; } if (wsi->ietf_spec_revision == 4) { /* * Calculate the 04 masking key to use when * sending data to server */ strcpy((char *)buf, wsi->key_b64); p = (char *)buf + strlen(wsi->key_b64); strcpy(p, wsi->utf8_token[WSI_TOKEN_NONCE].token); p += wsi->utf8_token[WSI_TOKEN_NONCE].token_len; strcpy(p, magic_websocket_04_masking_guid); SHA1(buf, strlen((char *)buf), wsi->masking_key_04); } accept_ok: /* allocate the per-connection user memory (if any) */ if (wsi->protocol->per_session_data_size && !libwebsocket_ensure_user_space(wsi)) goto bail2; /* clear his proxy connection timeout */ libwebsocket_set_timeout(wsi, NO_PENDING_TIMEOUT, 0); /* mark him as being alive */ wsi->state = WSI_STATE_ESTABLISHED; wsi->mode = LWS_CONNMODE_WS_CLIENT; debug("handshake OK for protocol %s\n", wsi->protocol->name); /* call him back to inform him he is up */ wsi->protocol->callback(context, wsi, LWS_CALLBACK_CLIENT_ESTABLISHED, wsi->user_space, NULL, 0); /* * inform all extensions, not just active ones since they * already know */ ext = context->extensions; while (ext && ext->callback) { v = NULL; for (n = 0; n < wsi->count_active_extensions; n++) if (wsi->active_extensions[n] == ext) v = wsi->active_extensions_user[n]; ext->callback(context, ext, wsi, LWS_EXT_CALLBACK_ANY_WSI_ESTABLISHED, v, NULL, 0); ext++; } return 0; bail3: if (wsi->c_protocol) free(wsi->c_protocol); bail2: if (wsi->c_callback) wsi->c_callback(context, wsi, LWS_CALLBACK_CLIENT_CONNECTION_ERROR, wsi->user_space, NULL, 0); libwebsocket_close_and_free_session(context, wsi, LWS_CLOSE_STATUS_NOSTATUS); // But this should be LWS_CLOSE_STATUS_PROTOCOL_ERR return 1; } /** * 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) { unsigned char buf[LWS_SEND_BUFFER_PRE_PADDING + 1 + MAX_BROADCAST_PAYLOAD + LWS_SEND_BUFFER_POST_PADDING]; struct libwebsocket *wsi; struct libwebsocket *new_wsi; int n; int m; ssize_t len; int accept_fd; unsigned int clilen; struct sockaddr_in cli_addr; struct timeval tv; char pkt[1024]; char *p = &pkt[0]; int more = 1; struct lws_tokens eff_buf; int opt = 1; char c; #ifdef LWS_OPENSSL_SUPPORT char ssl_err_buf[512]; #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++) { wsi = wsi_from_fd(context, context->fds[n].fd); libwebsocket_service_timeout_check(context, wsi, tv.tv_sec); } } /* just here for timeout management? */ if (pollfd == NULL) return 0; /* no, here to service a socket descriptor */ wsi = wsi_from_fd(context, pollfd->fd); if (wsi == NULL) return 1; switch (wsi->mode) { case LWS_CONNMODE_SERVER_LISTENER: /* pollin means a client has connected to us then */ if (!pollfd->revents & POLLIN) break; if (context->fds_count >= MAX_CLIENTS) { fprintf(stderr, "too busy to accept new client\n"); break; } /* listen socket got an unencrypted connection... */ clilen = sizeof(cli_addr); accept_fd = accept(pollfd->fd, (struct sockaddr *)&cli_addr, &clilen); if (accept_fd < 0) { debug("ERROR on accept\n"); return -1; } /* Disable Nagle */ opt = 1; setsockopt(accept_fd, IPPROTO_TCP, TCP_NODELAY, (const void *)&opt, sizeof(opt)); /* * look at who we connected to and give user code a chance * to reject based on client IP. There's no protocol selected * yet so we issue this to protocols[0] */ if ((context->protocols[0].callback)(context, wsi, LWS_CALLBACK_FILTER_NETWORK_CONNECTION, (void *)(long)accept_fd, NULL, 0)) { debug("Callback denied network connection\n"); #ifdef WIN32 closesocket(accept_fd); #else close(accept_fd); #endif break; } /* accepting connection to main listener */ new_wsi = libwebsocket_create_new_server_wsi(context); if (new_wsi == NULL) break; new_wsi->sock = accept_fd; #ifdef LWS_OPENSSL_SUPPORT new_wsi->ssl = NULL; if (context->use_ssl) { new_wsi->ssl = SSL_new(context->ssl_ctx); if (new_wsi->ssl == NULL) { fprintf(stderr, "SSL_new failed: %s\n", ERR_error_string(SSL_get_error( new_wsi->ssl, 0), NULL)); libwebsockets_decode_ssl_error(); free(new_wsi); break; } SSL_set_fd(new_wsi->ssl, accept_fd); n = SSL_accept(new_wsi->ssl); if (n != 1) { /* * browsers seem to probe with various * ssl params which fail then retry * and succeed */ debug("SSL_accept failed skt %u: %s\n", pollfd->fd, ERR_error_string(SSL_get_error( new_wsi->ssl, n), NULL)); SSL_free( new_wsi->ssl); free(new_wsi); break; } debug("accepted new SSL conn " "port %u on fd=%d SSL ver %s\n", ntohs(cli_addr.sin_port), accept_fd, SSL_get_version(new_wsi->ssl)); } else #endif debug("accepted new conn port %u on fd=%d\n", ntohs(cli_addr.sin_port), accept_fd); insert_wsi(context, new_wsi); /* * make sure NO events are seen yet on this new socket * (otherwise we inherit old fds[client].revents from * previous socket there and die mysteriously! ) */ context->fds[context->fds_count].revents = 0; context->fds[context->fds_count].events = POLLIN; context->fds[context->fds_count++].fd = accept_fd; /* external POLL support via protocol 0 */ context->protocols[0].callback(context, new_wsi, LWS_CALLBACK_ADD_POLL_FD, (void *)(long)accept_fd, NULL, POLLIN); break; case LWS_CONNMODE_BROADCAST_PROXY_LISTENER: /* as we are listening, POLLIN means accept() is needed */ if (!pollfd->revents & POLLIN) break; /* listen socket got an unencrypted connection... */ clilen = sizeof(cli_addr); accept_fd = accept(pollfd->fd, (struct sockaddr *)&cli_addr, &clilen); if (accept_fd < 0) { debug("ERROR on accept\n"); return -1; } if (context->fds_count >= MAX_CLIENTS) { fprintf(stderr, "too busy to accept new broadcast " "proxy client\n"); #ifdef WIN32 closesocket(accept_fd); #else close(accept_fd); #endif break; } /* create a dummy wsi for the connection and add it */ new_wsi = malloc(sizeof(struct libwebsocket)); memset(new_wsi, 0, sizeof(struct libwebsocket)); new_wsi->sock = accept_fd; new_wsi->mode = LWS_CONNMODE_BROADCAST_PROXY; new_wsi->state = WSI_STATE_ESTABLISHED; new_wsi->count_active_extensions = 0; /* note which protocol we are proxying */ new_wsi->protocol_index_for_broadcast_proxy = wsi->protocol_index_for_broadcast_proxy; insert_wsi(context, new_wsi); /* add connected socket to internal poll array */ context->fds[context->fds_count].revents = 0; context->fds[context->fds_count].events = POLLIN; context->fds[context->fds_count++].fd = accept_fd; /* external POLL support via protocol 0 */ context->protocols[0].callback(context, new_wsi, LWS_CALLBACK_ADD_POLL_FD, (void *)(long)accept_fd, NULL, POLLIN); break; case LWS_CONNMODE_BROADCAST_PROXY: /* handle session socket closed */ if (pollfd->revents & (POLLERR | POLLHUP)) { debug("Session Socket %p (fd=%d) dead\n", (void *)wsi, pollfd->fd); libwebsocket_close_and_free_session(context, wsi, LWS_CLOSE_STATUS_NORMAL); return 1; } /* * either extension code with stuff to spill, or the user code, * requested a callback when it was OK to write */ if (pollfd->revents & POLLOUT) if (lws_handle_POLLOUT_event(context, wsi, pollfd) < 0) { libwebsocket_close_and_free_session( context, wsi, LWS_CLOSE_STATUS_NORMAL); return 1; } /* any incoming data ready? */ if (!(pollfd->revents & POLLIN)) break; /* get the issued broadcast payload from the socket */ len = read(pollfd->fd, buf + LWS_SEND_BUFFER_PRE_PADDING, MAX_BROADCAST_PAYLOAD); if (len < 0) { fprintf(stderr, "Error reading broadcast payload\n"); break; } /* broadcast it to all guys with this protocol index */ for (n = 0; n < FD_HASHTABLE_MODULUS; n++) { for (m = 0; m < context->fd_hashtable[n].length; m++) { new_wsi = context->fd_hashtable[n].wsi[m]; /* only to clients we are serving to */ if (new_wsi->mode != LWS_CONNMODE_WS_SERVING) continue; /* * never broadcast to non-established * connection */ if (new_wsi->state != WSI_STATE_ESTABLISHED) continue; /* * only broadcast to connections using * the requested protocol */ if (new_wsi->protocol->protocol_index != wsi->protocol_index_for_broadcast_proxy) continue; /* broadcast it to this connection */ new_wsi->protocol->callback(context, new_wsi, LWS_CALLBACK_BROADCAST, new_wsi->user_space, buf + LWS_SEND_BUFFER_PRE_PADDING, len); } } break; case LWS_CONNMODE_WS_CLIENT_WAITING_PROXY_REPLY: /* handle proxy hung up on us */ if (pollfd->revents & (POLLERR | POLLHUP)) { fprintf(stderr, "Proxy connection %p (fd=%d) dead\n", (void *)wsi, pollfd->fd); libwebsocket_close_and_free_session(context, wsi, LWS_CLOSE_STATUS_NOSTATUS); return 1; } n = recv(wsi->sock, pkt, sizeof pkt, 0); if (n < 0) { libwebsocket_close_and_free_session(context, wsi, LWS_CLOSE_STATUS_NOSTATUS); fprintf(stderr, "ERROR reading from proxy socket\n"); return 1; } pkt[13] = '\0'; if (strcmp(pkt, "HTTP/1.0 200 ") != 0) { libwebsocket_close_and_free_session(context, wsi, LWS_CLOSE_STATUS_NOSTATUS); fprintf(stderr, "ERROR from proxy: %s\n", pkt); return 1; } /* clear his proxy connection timeout */ libwebsocket_set_timeout(wsi, NO_PENDING_TIMEOUT, 0); /* fallthru */ case LWS_CONNMODE_WS_CLIENT_ISSUE_HANDSHAKE: #ifdef LWS_OPENSSL_SUPPORT if (wsi->use_ssl && !wsi->ssl) { wsi->ssl = SSL_new(context->ssl_client_ctx); wsi->client_bio = BIO_new_socket(wsi->sock, BIO_NOCLOSE); SSL_set_bio(wsi->ssl, wsi->client_bio, wsi->client_bio); SSL_set_ex_data(wsi->ssl, openssl_websocket_private_data_index, context); } if (wsi->use_ssl) { if (SSL_connect(wsi->ssl) <= 0) { /* * retry if new data comes until we * run into the connection timeout or win */ fprintf(stderr, "SSL connect error %s\n", ERR_error_string(ERR_get_error(), ssl_err_buf)); return 0; } n = SSL_get_verify_result(wsi->ssl); if ((n != X509_V_OK) && ( n != X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT || wsi->use_ssl != 2)) { fprintf(stderr, "server's cert didn't " "look good %d\n", n); libwebsocket_close_and_free_session(context, wsi, LWS_CLOSE_STATUS_NOSTATUS); return 1; } } else wsi->ssl = NULL; #endif p = libwebsockets_generate_client_handshake(context, wsi, p); if (p == NULL) return 1; /* send our request to the server */ #ifdef LWS_OPENSSL_SUPPORT if (wsi->use_ssl) n = SSL_write(wsi->ssl, pkt, p - pkt); else #endif n = send(wsi->sock, pkt, p - pkt, 0); if (n < 0) { fprintf(stderr, "ERROR writing to client socket\n"); libwebsocket_close_and_free_session(context, wsi, LWS_CLOSE_STATUS_NOSTATUS); return 1; } wsi->parser_state = WSI_TOKEN_NAME_PART; wsi->mode = LWS_CONNMODE_WS_CLIENT_WAITING_SERVER_REPLY; libwebsocket_set_timeout(wsi, PENDING_TIMEOUT_AWAITING_SERVER_RESPONSE, 5); break; case LWS_CONNMODE_WS_CLIENT_WAITING_SERVER_REPLY: /* handle server hung up on us */ if (pollfd->revents & (POLLERR | POLLHUP)) { fprintf(stderr, "Server connection %p (fd=%d) dead\n", (void *)wsi, pollfd->fd); goto bail3; } /* interpret the server response */ /* * HTTP/1.1 101 Switching Protocols * Upgrade: websocket * Connection: Upgrade * Sec-WebSocket-Accept: me89jWimTRKTWwrS3aRrL53YZSo= * Sec-WebSocket-Nonce: AQIDBAUGBwgJCgsMDQ4PEC== * Sec-WebSocket-Protocol: chat */ /* * we have to take some care here to only take from the * socket bytewise. The browser may (and has been seen to * in the case that onopen() performs websocket traffic) * coalesce both handshake response and websocket traffic * in one packet, since at that point the connection is * definitively ready from browser pov. */ len = 1; while (wsi->parser_state != WSI_PARSING_COMPLETE && len > 0) { #ifdef LWS_OPENSSL_SUPPORT if (wsi->use_ssl) len = SSL_read(wsi->ssl, &c, 1); else #endif len = recv(wsi->sock, &c, 1, 0); libwebsocket_parse(wsi, c); } /* * hs may also be coming in multiple packets, there is a 5-sec * libwebsocket timeout still active here too, so if parsing did * not complete just wait for next packet coming in this state */ if (wsi->parser_state != WSI_PARSING_COMPLETE) break; /* * otherwise deal with the handshake. If there's any * packet traffic already arrived we'll trigger poll() again * right away and deal with it that way */ return lws_client_interpret_server_handshake(context, wsi); bail3: if (wsi->c_protocol) free(wsi->c_protocol); libwebsocket_close_and_free_session(context, wsi, LWS_CLOSE_STATUS_NOSTATUS); return 1; case LWS_CONNMODE_WS_CLIENT_WAITING_EXTENSION_CONNECT: fprintf(stderr, "LWS_CONNMODE_WS_CLIENT_WAITING_EXTENSION_CONNECT\n"); break; case LWS_CONNMODE_WS_CLIENT_PENDING_CANDIDATE_CHILD: fprintf(stderr, "LWS_CONNMODE_WS_CLIENT_PENDING_CANDIDATE_CHILD\n"); break; case LWS_CONNMODE_WS_SERVING: case LWS_CONNMODE_WS_CLIENT: /* handle session socket closed */ if (pollfd->revents & (POLLERR | POLLHUP)) { fprintf(stderr, "Session Socket %p (fd=%d) dead\n", (void *)wsi, pollfd->fd); libwebsocket_close_and_free_session(context, wsi, LWS_CLOSE_STATUS_NOSTATUS); return 1; } /* 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 1; } /* any incoming data ready? */ if (!(pollfd->revents & POLLIN)) break; #ifdef LWS_OPENSSL_SUPPORT 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) { fprintf(stderr, "Socket read returned %d\n", eff_buf.token_len); if (errno != EINTR) libwebsocket_close_and_free_session(context, wsi, LWS_CLOSE_STATUS_NOSTATUS); return 1; } if (!eff_buf.token_len) { libwebsocket_close_and_free_session(context, wsi, LWS_CLOSE_STATUS_NOSTATUS); return 1; } /* * 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) { fprintf(stderr, "Extension reports fatal error\n"); libwebsocket_close_and_free_session( context, wsi, LWS_CLOSE_STATUS_NOSTATUS); return 1; } 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 1; } eff_buf.token = NULL; eff_buf.token_len = 0; } break; } 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 *wsi; struct libwebsocket_extension *ext; for (n = 0; n < FD_HASHTABLE_MODULUS; n++) for (m = 0; m < context->fd_hashtable[n].length; m++) { wsi = context->fd_hashtable[n].wsi[m]; 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, 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 } /** * 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) { /* fprintf(stderr, "Listen Socket dead\n"); */ return -1; } /* handle accept on listening socket? */ 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; for (n = 0; n < context->fds_count; n++) if (context->fds[n].fd == wsi->sock) { context->fds[n].events |= POLLOUT; n = context->fds_count + 1; } if (n == context->fds_count) fprintf(stderr, "libwebsocket_callback_on_writable: " "failed to find socket %d\n", wsi->sock); /* 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; int m; struct libwebsocket *wsi; for (n = 0; n < FD_HASHTABLE_MODULUS; n++) { for (m = 0; m < context->fd_hashtable[n].length; m++) { wsi = context->fd_hashtable[n].wsi[m]; 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; } /** * 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) { struct libwebsocket_context *context = wsi->protocol->owning_server; int n; for (n = 0; n < context->fds_count; n++) if (context->fds[n].fd == wsi->sock) { if (enable) context->fds[n].events |= POLLIN; else context->fds[n].events &= ~POLLIN; return 0; } if (enable) /* 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); #if 0 fprintf(stderr, "libwebsocket_rx_flow_control " "unable to find socket\n"); #endif return 1; } /** * 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 /** * 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 * @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 * * 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, int gid, int uid, unsigned int options) { int n; int m; int sockfd = 0; int fd; struct sockaddr_in serv_addr, cli_addr; int opt = 1; struct libwebsocket_context *context = NULL; unsigned int slen; char *p; char hostname[1024] = ""; // struct hostent *he; struct libwebsocket *wsi; struct sockaddr sa; #ifdef LWS_OPENSSL_SUPPORT SSL_METHOD *method; char ssl_err_buf[512]; #endif #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. */ fprintf(stderr, "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("Ws2_32.dll"); if (wsdll) poll = (PFNWSAPOLL)GetProcAddress(wsdll, "WSAPoll"); } #endif context = malloc(sizeof(struct libwebsocket_context)); if (!context) { fprintf(stderr, "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; context->fds_count = 0; context->extensions = extensions; context->last_timeout_check_s = 0; #ifdef WIN32 context->fd_random = 0; #else context->fd_random = open(SYSTEM_RANDOM_FILEPATH, O_RDONLY); if (context->fd_random < 0) { fprintf(stderr, "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 /* 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); // fprintf(stderr, "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); // fprintf(stderr, "context->canonical_hostname = %s\n", // context->canonical_hostname); /* 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) { fprintf(stderr, "http_proxy needs to be ads:port\n"); return NULL; } *p = '\0'; context->http_proxy_port = atoi(p + 1); fprintf(stderr, "Using proxy %s:%u\n", context->http_proxy_address, context->http_proxy_port); } if (port) { #ifdef LWS_OPENSSL_SUPPORT context->use_ssl = ssl_cert_filepath != NULL && ssl_private_key_filepath != NULL; if (context->use_ssl) fprintf(stderr, " Compiled with SSL support, " "using it\n"); else fprintf(stderr, " Compiled with SSL support, " "not using it\n"); #else if (ssl_cert_filepath != NULL && ssl_private_key_filepath != NULL) { fprintf(stderr, " Not compiled for OpenSSl support!\n"); return NULL; } fprintf(stderr, " Compiled without SSL support, " "serving unencrypted\n"); #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) { fprintf(stderr, "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) { fprintf(stderr, "problem creating ssl context: %s\n", ERR_error_string(ERR_get_error(), ssl_err_buf)); return NULL; } /* client context */ if (port == CONTEXT_PORT_NO_LISTEN) { method = (SSL_METHOD *)SSLv23_client_method(); if (!method) { fprintf(stderr, "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) { fprintf(stderr, "problem creating ssl context: %s\n", ERR_error_string(ERR_get_error(), ssl_err_buf)); return NULL; } /* openssl init for cert verification (for client sockets) */ if (!SSL_CTX_load_verify_locations( context->ssl_client_ctx, NULL, LWS_OPENSSL_CLIENT_CERTS)) fprintf(stderr, "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); /* * 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); } /* 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_file(context->ssl_ctx, ssl_cert_filepath, SSL_FILETYPE_PEM); if (n != 1) { fprintf(stderr, "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) { fprintf(stderr, "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)) { fprintf(stderr, "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; /* fd hashtable init */ for (n = 0; n < FD_HASHTABLE_MODULUS; n++) context->fd_hashtable[n].length = 0; /* set up our external listening socket we serve on */ if (port) { sockfd = socket(AF_INET, SOCK_STREAM, 0); if (sockfd < 0) { fprintf(stderr, "ERROR opening socket"); 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) { fprintf(stderr, "ERROR on binding to port %d (%d %d)\n", port, n, errno); return NULL; } wsi = malloc(sizeof(struct libwebsocket)); memset(wsi, 0, sizeof(struct libwebsocket)); wsi->sock = sockfd; wsi->count_active_extensions = 0; wsi->mode = LWS_CONNMODE_SERVER_LISTENER; insert_wsi(context, wsi); listen(sockfd, 5); fprintf(stderr, " Listening on port %d\n", port); /* list in the internal poll array */ context->fds[context->fds_count].fd = sockfd; context->fds[context->fds_count++].events = POLLIN; /* external POLL support via protocol 0 */ context->protocols[0].callback(context, wsi, LWS_CALLBACK_ADD_POLL_FD, (void *)(long)sockfd, NULL, POLLIN); } /* * 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)) fprintf(stderr, "setgid: %s\n", strerror(errno)); if (uid != -1) if (setuid(uid)) fprintf(stderr, "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++) { debug(" 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) { fprintf(stderr, "ERROR opening socket"); 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) { fprintf(stderr, "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) { fprintf(stderr, "getsockname failed\n"); return NULL; } protocols[context->count_protocols].broadcast_socket_port = ntohs(cli_addr.sin_port); listen(fd, 5); debug(" Protocol %s broadcast socket %d\n", protocols[context->count_protocols].name, ntohs(cli_addr.sin_port)); /* dummy wsi per broadcast proxy socket */ wsi = malloc(sizeof(struct libwebsocket)); 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(context, wsi); /* list in internal poll array */ context->fds[context->fds_count].fd = fd; context->fds[context->fds_count].events = POLLIN; context->fds[context->fds_count].revents = 0; context->fds_count++; /* external POLL support via protocol 0 */ context->protocols[0].callback(context, wsi, LWS_CALLBACK_ADD_POLL_FD, (void *)(long)fd, NULL, POLLIN); } /* * 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) { debug(" Extension: %s\n", extensions->name); extensions->callback(context, extensions, NULL, 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) { fprintf(stderr, "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) { fprintf(stderr, "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; int m; 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 < FD_HASHTABLE_MODULUS; n++) { for (m = 0; m < context->fd_hashtable[n].length; m++) { wsi = context->fd_hashtable[n].wsi[m]; 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; 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; } 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) { fprintf(stderr, "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; }