2 * libwebsockets - small server side websockets and web server implementation
4 * Copyright (C) 2010 Andy Green <andy@warmcat.com>
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation:
9 * version 2.1 of the License.
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
22 #include "private-libwebsockets.h"
30 #ifdef LWS_OPENSSL_SUPPORT
31 int openssl_websocket_private_data_index;
35 * In-place str to lower case
47 /* file descriptor hash management */
50 wsi_from_fd(struct libwebsocket_context *context, int fd)
52 int h = LWS_FD_HASH(fd);
55 for (n = 0; n < context->fd_hashtable[h].length; n++)
56 if (context->fd_hashtable[h].wsi[n]->sock == fd)
57 return context->fd_hashtable[h].wsi[n];
63 insert_wsi(struct libwebsocket_context *context, struct libwebsocket *wsi)
65 int h = LWS_FD_HASH(wsi->sock);
67 if (context->fd_hashtable[h].length == MAX_CLIENTS - 1) {
68 fprintf(stderr, "hash table overflow\n");
72 context->fd_hashtable[h].wsi[context->fd_hashtable[h].length++] = wsi;
78 delete_from_fd(struct libwebsocket_context *context, int fd)
80 int h = LWS_FD_HASH(fd);
83 for (n = 0; n < context->fd_hashtable[h].length; n++)
84 if (context->fd_hashtable[h].wsi[n]->sock == fd) {
85 while (n < context->fd_hashtable[h].length) {
86 context->fd_hashtable[h].wsi[n] =
87 context->fd_hashtable[h].wsi[n + 1];
90 context->fd_hashtable[h].length--;
95 fprintf(stderr, "Failed to find fd %d requested for "
96 "delete in hashtable\n", fd);
100 #ifdef LWS_OPENSSL_SUPPORT
102 libwebsockets_decode_ssl_error(void)
107 while ((err = ERR_get_error()) != 0) {
108 ERR_error_string_n(err, buf, sizeof(buf));
109 fprintf(stderr, "*** %s\n", buf);
116 interface_to_sa(const char* ifname, struct sockaddr_in *addr, size_t addrlen)
124 struct sockaddr_in *sin;
127 for (ifc = ifr; ifc != NULL; ifc = ifc->ifa_next) {
128 if (strcmp(ifc->ifa_name, ifname))
130 if (ifc->ifa_addr == NULL)
132 sin = (struct sockaddr_in *)ifc->ifa_addr;
133 if (sin->sin_family != AF_INET)
135 memcpy(addr, sin, addrlen);
145 libwebsocket_close_and_free_session(struct libwebsocket_context *context,
146 struct libwebsocket *wsi, enum lws_close_status reason)
150 unsigned char buf[LWS_SEND_BUFFER_PRE_PADDING + 2 +
151 LWS_SEND_BUFFER_POST_PADDING];
154 struct lws_tokens eff_buf;
159 old_state = wsi->state;
161 if (old_state == WSI_STATE_DEAD_SOCKET)
164 wsi->close_reason = reason;
167 * flush any tx pending from extensions, since we may send close packet
168 * if there are problems with send, just nuke the connection
174 /* default to nobody has more to spill */
177 eff_buf.token = NULL;
178 eff_buf.token_len = 0;
180 /* show every extension the new incoming data */
182 for (n = 0; n < wsi->count_active_extensions; n++) {
183 m = wsi->active_extensions[n]->callback(
184 wsi->protocol->owning_server, wsi,
185 LWS_EXT_CALLBACK_FLUSH_PENDING_TX,
186 wsi->active_extensions_user[n], &eff_buf, 0);
188 fprintf(stderr, "Extension reports "
190 goto just_kill_connection;
194 * at least one extension told us he has more
195 * to spill, so we will go around again after
200 /* assuming they left us something to send, send it */
202 if (eff_buf.token_len)
203 if (lws_issue_raw(wsi, (unsigned char *)eff_buf.token,
205 goto just_kill_connection;
209 * signal we are closing, libsocket_write will
210 * add any necessary version-specific stuff. If the write fails,
211 * no worries we are closing anyway. If we didn't initiate this
212 * close, then our state has been changed to
213 * WSI_STATE_RETURNED_CLOSE_ALREADY and we will skip this.
215 * Likewise if it's a second call to close this connection after we
216 * sent the close indication to the peer already, we are in state
217 * WSI_STATE_AWAITING_CLOSE_ACK and will skip doing this a second time.
220 if (old_state == WSI_STATE_ESTABLISHED &&
221 reason != LWS_CLOSE_STATUS_NOSTATUS) {
222 n = libwebsocket_write(wsi, &buf[LWS_SEND_BUFFER_PRE_PADDING],
226 * we have sent a nice protocol level indication we
227 * now wish to close, we should not send anything more
230 wsi->state = WSI_STATE_AWAITING_CLOSE_ACK;
232 /* and we should wait for a reply for a bit */
234 libwebsocket_set_timeout(wsi,
235 PENDING_TIMEOUT_CLOSE_ACK, 5);
237 fprintf(stderr, "sent close indication, awaiting ack\n");
242 /* else, the send failed and we should just hang up */
245 just_kill_connection:
247 * we won't be servicing or receiving anything further from this guy
248 * remove this fd from wsi mapping hashtable
251 delete_from_fd(context, wsi->sock);
253 /* delete it from the internal poll list if still present */
255 for (n = 0; n < context->fds_count; n++) {
256 if (context->fds[n].fd != wsi->sock)
258 while (n < context->fds_count - 1) {
259 context->fds[n] = context->fds[n + 1];
262 context->fds_count--;
263 /* we only have to deal with one */
264 n = context->fds_count;
267 /* remove also from external POLL support via protocol 0 */
269 context->protocols[0].callback(context, wsi,
270 LWS_CALLBACK_DEL_POLL_FD, (void *)(long)wsi->sock, NULL, 0);
272 wsi->state = WSI_STATE_DEAD_SOCKET;
274 /* tell the user it's all over for this guy */
276 if (wsi->protocol && wsi->protocol->callback &&
277 old_state == WSI_STATE_ESTABLISHED)
278 wsi->protocol->callback(context, wsi, LWS_CALLBACK_CLOSED,
279 wsi->user_space, NULL, 0);
281 /* deallocate any active extension contexts */
283 for (n = 0; n < wsi->count_active_extensions; n++) {
284 if (!wsi->active_extensions[n]->callback)
287 wsi->active_extensions[n]->callback(context, wsi,
288 LWS_EXT_CALLBACK_DESTROY,
289 wsi->active_extensions_user[n], NULL, 0);
291 free(wsi->active_extensions_user[n]);
294 /* free up his parsing allocations */
296 for (n = 0; n < WSI_TOKEN_COUNT; n++)
297 if (wsi->utf8_token[n].token)
298 free(wsi->utf8_token[n].token);
300 /* fprintf(stderr, "closing fd=%d\n", wsi->sock); */
302 #ifdef LWS_OPENSSL_SUPPORT
304 n = SSL_get_fd(wsi->ssl);
305 SSL_shutdown(wsi->ssl);
314 shutdown(wsi->sock, SHUT_RDWR);
316 closesocket(wsi->sock);
320 #ifdef LWS_OPENSSL_SUPPORT
324 free(wsi->user_space);
330 * libwebsockets_hangup_on_client() - Server calls to terminate client
332 * @context: libwebsockets context
333 * @fd: Connection socket descriptor
337 libwebsockets_hangup_on_client(struct libwebsocket_context *context, int fd)
339 struct libwebsocket *wsi = wsi_from_fd(context, fd);
344 libwebsocket_close_and_free_session(context, wsi,
345 LWS_CLOSE_STATUS_NOSTATUS);
350 * libwebsockets_get_peer_addresses() - Get client address information
351 * @fd: Connection socket descriptor
352 * @name: Buffer to take client address name
353 * @name_len: Length of client address name buffer
354 * @rip: Buffer to take client address IP qotted quad
355 * @rip_len: Length of client address IP buffer
357 * This function fills in @name and @rip with the name and IP of
358 * the client connected with socket descriptor @fd. Names may be
359 * truncated if there is not enough room. If either cannot be
360 * determined, they will be returned as valid zero-length strings.
364 libwebsockets_get_peer_addresses(int fd, char *name, int name_len,
365 char *rip, int rip_len)
368 struct sockaddr_in sin;
369 struct hostent *host;
370 struct hostent *host1;
379 if (getpeername(fd, (struct sockaddr *) &sin, &len) < 0) {
380 perror("getpeername");
384 host = gethostbyaddr((char *) &sin.sin_addr, sizeof sin.sin_addr,
387 perror("gethostbyaddr");
391 strncpy(name, host->h_name, name_len);
392 name[name_len - 1] = '\0';
394 host1 = gethostbyname(host->h_name);
400 p = host1->h_addr_list[n++];
403 if (host1->h_addrtype != AF_INET)
406 sprintf(ip, "%d.%d.%d.%d",
407 p[0], p[1], p[2], p[3]);
409 strncpy(rip, ip, rip_len);
410 rip[rip_len - 1] = '\0';
414 int libwebsockets_get_random(struct libwebsocket_context *context,
421 for (n = 0; n < len; n++)
422 p[n] = (unsigned char)rand();
424 n = read(context->fd_random, p, len);
430 void libwebsockets_00_spaceout(char *key, int spaces, int seed)
436 if (*key && (seed & 1))
440 p = key + strlen(key);
449 void libwebsockets_00_spam(char *key, int count, int seed)
456 if (*key && (seed & 1))
460 p = key + strlen(key);
465 *key++ = 0x21 + ((seed & 0xffff) % 15);
466 /* 4 would use it up too fast.. not like it matters */
471 int lws_send_pipe_choked(struct libwebsocket *wsi)
476 fds.events = POLLOUT;
479 if (poll(&fds, 1, 0) != 1)
482 if ((fds.revents & POLLOUT) == 0)
485 /* okay to send another packet without blocking */
491 lws_handle_POLLOUT_event(struct libwebsocket_context *context,
492 struct libwebsocket *wsi, struct pollfd *pollfd)
494 struct lws_tokens eff_buf;
499 if (!wsi->extension_data_pending)
503 * check in on the active extensions, see if they
504 * had pending stuff to spill... they need to get the
505 * first look-in otherwise sequence will be disordered
507 * NULL, zero-length eff_buf means just spill pending
513 /* default to nobody has more to spill */
516 eff_buf.token = NULL;
517 eff_buf.token_len = 0;
519 /* give every extension a chance to spill */
521 for (n = 0; n < wsi->count_active_extensions; n++) {
522 m = wsi->active_extensions[n]->callback(
523 wsi->protocol->owning_server, wsi,
524 LWS_EXT_CALLBACK_PACKET_TX_PRESEND,
525 wsi->active_extensions_user[n], &eff_buf, 0);
527 fprintf(stderr, "extension reports fatal error\n");
532 * at least one extension told us he has more
533 * to spill, so we will go around again after
538 /* assuming they gave us something to send, send it */
540 if (eff_buf.token_len) {
541 if (lws_issue_raw(wsi, (unsigned char *)eff_buf.token,
547 /* no extension has more to spill */
553 * There's more to spill from an extension, but we just sent
554 * something... did that leave the pipe choked?
557 if (!lws_send_pipe_choked(wsi))
558 /* no we could add more */
561 fprintf(stderr, "choked in POLLOUT service\n");
564 * Yes, he's choked. Leave the POLLOUT masked on so we will
565 * come back here when he is unchoked. Don't call the user
566 * callback to enforce ordering of spilling, he'll get called
567 * when we come back here and there's nothing more to spill.
573 wsi->extension_data_pending = 0;
578 pollfd->events &= ~POLLOUT;
580 /* external POLL support via protocol 0 */
581 context->protocols[0].callback(context, wsi,
582 LWS_CALLBACK_CLEAR_MODE_POLL_FD,
583 (void *)(long)wsi->sock, NULL, POLLOUT);
585 wsi->protocol->callback(context, wsi,
586 LWS_CALLBACK_CLIENT_WRITEABLE,
596 * libwebsocket_service_fd() - Service polled socket with something waiting
597 * @context: Websocket context
598 * @pollfd: The pollfd entry describing the socket fd and which events
601 * This function closes any active connections and then frees the
602 * context. After calling this, any further use of the context is
607 libwebsocket_service_fd(struct libwebsocket_context *context,
608 struct pollfd *pollfd)
610 unsigned char buf[LWS_SEND_BUFFER_PRE_PADDING + 1 + MAX_BROADCAST_PAYLOAD +
611 LWS_SEND_BUFFER_POST_PADDING];
612 struct libwebsocket *wsi;
613 struct libwebsocket *new_wsi;
619 struct sockaddr_in cli_addr;
621 static const char magic_websocket_guid[] =
622 "258EAFA5-E914-47DA-95CA-C5AB0DC85B11";
623 static const char magic_websocket_04_masking_guid[] =
624 "61AC5F19-FBBA-4540-B96F-6561F1AB40A8";
633 struct lws_tokens eff_buf;
635 struct libwebsocket_extension *ext;
637 #ifdef LWS_OPENSSL_SUPPORT
638 char ssl_err_buf[512];
641 * you can call us with pollfd = NULL to just allow the once-per-second
642 * global timeout checks; if less than a second since the last check
643 * it returns immediately then.
646 gettimeofday(&tv, NULL);
648 if (context->last_timeout_check_s != tv.tv_sec) {
649 context->last_timeout_check_s = tv.tv_sec;
651 /* global timeout check once per second */
653 for (n = 0; n < context->fds_count; n++) {
654 wsi = wsi_from_fd(context, context->fds[n].fd);
655 if (!wsi->pending_timeout)
659 * if we went beyond the allowed time, kill the
663 if (tv.tv_sec > wsi->pending_timeout_limit) {
664 fprintf(stderr, "TIMEDOUT WAITING\n");
665 libwebsocket_close_and_free_session(context,
666 wsi, LWS_CLOSE_STATUS_NOSTATUS);
671 /* just here for timeout management? */
676 /* no, here to service a socket descriptor */
678 wsi = wsi_from_fd(context, pollfd->fd);
684 case LWS_CONNMODE_SERVER_LISTENER:
686 /* pollin means a client has connected to us then */
688 if (!pollfd->revents & POLLIN)
691 /* listen socket got an unencrypted connection... */
693 clilen = sizeof(cli_addr);
694 accept_fd = accept(pollfd->fd, (struct sockaddr *)&cli_addr,
697 fprintf(stderr, "ERROR on accept");
701 if (context->fds_count >= MAX_CLIENTS) {
702 fprintf(stderr, "too busy to accept new client\n");
704 closesocket(accept_fd);
712 * look at who we connected to and give user code a chance
713 * to reject based on client IP. There's no protocol selected
714 * yet so we issue this to protocols[0]
717 if ((context->protocols[0].callback)(context, wsi,
718 LWS_CALLBACK_FILTER_NETWORK_CONNECTION,
719 (void*)(long)accept_fd, NULL, 0)) {
720 fprintf(stderr, "Callback denied network connection\n");
722 closesocket(accept_fd);
729 /* accepting connection to main listener */
731 new_wsi = malloc(sizeof(struct libwebsocket));
732 if (new_wsi == NULL) {
733 fprintf(stderr, "Out of memory for new connection\n");
737 memset(new_wsi, 0, sizeof (struct libwebsocket));
738 new_wsi->sock = accept_fd;
739 new_wsi->count_active_extensions = 0;
740 new_wsi->pending_timeout = NO_PENDING_TIMEOUT;
742 #ifdef LWS_OPENSSL_SUPPORT
745 if (context->use_ssl) {
747 new_wsi->ssl = SSL_new(context->ssl_ctx);
748 if (new_wsi->ssl == NULL) {
749 fprintf(stderr, "SSL_new failed: %s\n",
750 ERR_error_string(SSL_get_error(
751 new_wsi->ssl, 0), NULL));
752 libwebsockets_decode_ssl_error();
757 SSL_set_fd(new_wsi->ssl, accept_fd);
759 n = SSL_accept(new_wsi->ssl);
762 * browsers seem to probe with various
763 * ssl params which fail then retry
766 debug("SSL_accept failed skt %u: %s\n",
768 ERR_error_string(SSL_get_error(
769 new_wsi->ssl, n), NULL));
776 debug("accepted new SSL conn "
777 "port %u on fd=%d SSL ver %s\n",
778 ntohs(cli_addr.sin_port), accept_fd,
779 SSL_get_version(new_wsi->ssl));
783 debug("accepted new conn port %u on fd=%d\n",
784 ntohs(cli_addr.sin_port), accept_fd);
786 /* intialize the instance struct */
788 new_wsi->state = WSI_STATE_HTTP;
789 new_wsi->name_buffer_pos = 0;
790 new_wsi->mode = LWS_CONNMODE_WS_SERVING;
792 for (n = 0; n < WSI_TOKEN_COUNT; n++) {
793 new_wsi->utf8_token[n].token = NULL;
794 new_wsi->utf8_token[n].token_len = 0;
798 * these can only be set once the protocol is known
799 * we set an unestablished connection's protocol pointer
800 * to the start of the supported list, so it can look
801 * for matching ones during the handshake
803 new_wsi->protocol = context->protocols;
804 new_wsi->user_space = NULL;
807 * Default protocol is 76 / 00
808 * After 76, there's a header specified to inform which
809 * draft the client wants, when that's seen we modify
810 * the individual connection's spec revision accordingly
812 new_wsi->ietf_spec_revision = 0;
814 insert_wsi(context, new_wsi);
817 * make sure NO events are seen yet on this new socket
818 * (otherwise we inherit old fds[client].revents from
819 * previous socket there and die mysteriously! )
821 context->fds[context->fds_count].revents = 0;
823 context->fds[context->fds_count].events = POLLIN;
824 context->fds[context->fds_count++].fd = accept_fd;
826 /* external POLL support via protocol 0 */
827 context->protocols[0].callback(context, new_wsi,
828 LWS_CALLBACK_ADD_POLL_FD,
829 (void *)(long)accept_fd, NULL, POLLIN);
833 case LWS_CONNMODE_BROADCAST_PROXY_LISTENER:
835 /* as we are listening, POLLIN means accept() is needed */
837 if (!pollfd->revents & POLLIN)
840 /* listen socket got an unencrypted connection... */
842 clilen = sizeof(cli_addr);
843 accept_fd = accept(pollfd->fd, (struct sockaddr *)&cli_addr,
846 fprintf(stderr, "ERROR on accept");
850 if (context->fds_count >= MAX_CLIENTS) {
851 fprintf(stderr, "too busy to accept new broadcast "
854 closesocket(accept_fd);
861 /* create a dummy wsi for the connection and add it */
863 new_wsi = malloc(sizeof(struct libwebsocket));
864 memset(new_wsi, 0, sizeof (struct libwebsocket));
865 new_wsi->sock = accept_fd;
866 new_wsi->mode = LWS_CONNMODE_BROADCAST_PROXY;
867 new_wsi->state = WSI_STATE_ESTABLISHED;
868 new_wsi->count_active_extensions = 0;
869 /* note which protocol we are proxying */
870 new_wsi->protocol_index_for_broadcast_proxy =
871 wsi->protocol_index_for_broadcast_proxy;
872 insert_wsi(context, new_wsi);
874 /* add connected socket to internal poll array */
876 context->fds[context->fds_count].revents = 0;
877 context->fds[context->fds_count].events = POLLIN;
878 context->fds[context->fds_count++].fd = accept_fd;
880 /* external POLL support via protocol 0 */
881 context->protocols[0].callback(context, new_wsi,
882 LWS_CALLBACK_ADD_POLL_FD,
883 (void *)(long)accept_fd, NULL, POLLIN);
887 case LWS_CONNMODE_BROADCAST_PROXY:
889 /* handle session socket closed */
891 if (pollfd->revents & (POLLERR | POLLHUP)) {
893 debug("Session Socket %p (fd=%d) dead\n",
894 (void *)wsi, pollfd->fd);
896 libwebsocket_close_and_free_session(context, wsi,
897 LWS_CLOSE_STATUS_NORMAL);
902 * either extension code with stuff to spill, or the user code,
903 * requested a callback when it was OK to write
906 if (pollfd->revents & POLLOUT)
907 if (lws_handle_POLLOUT_event(context, wsi, pollfd) < 0) {
908 libwebsocket_close_and_free_session(context, wsi,
909 LWS_CLOSE_STATUS_NORMAL);
913 /* any incoming data ready? */
915 if (!(pollfd->revents & POLLIN))
918 /* get the issued broadcast payload from the socket */
920 len = read(pollfd->fd, buf + LWS_SEND_BUFFER_PRE_PADDING,
921 MAX_BROADCAST_PAYLOAD);
923 fprintf(stderr, "Error reading broadcast payload\n");
927 /* broadcast it to all guys with this protocol index */
929 for (n = 0; n < FD_HASHTABLE_MODULUS; n++) {
931 for (m = 0; m < context->fd_hashtable[n].length; m++) {
933 new_wsi = context->fd_hashtable[n].wsi[m];
935 /* only to clients we are serving to */
937 if (new_wsi->mode != LWS_CONNMODE_WS_SERVING)
941 * never broadcast to non-established
945 if (new_wsi->state != WSI_STATE_ESTABLISHED)
949 * only broadcast to connections using
950 * the requested protocol
953 if (new_wsi->protocol->protocol_index !=
954 wsi->protocol_index_for_broadcast_proxy)
957 /* broadcast it to this connection */
959 new_wsi->protocol->callback(context, new_wsi,
960 LWS_CALLBACK_BROADCAST,
962 buf + LWS_SEND_BUFFER_PRE_PADDING, len);
967 case LWS_CONNMODE_WS_CLIENT_WAITING_PROXY_REPLY:
969 /* handle proxy hung up on us */
971 if (pollfd->revents & (POLLERR | POLLHUP)) {
973 fprintf(stderr, "Proxy connection %p (fd=%d) dead\n",
974 (void *)wsi, pollfd->fd);
976 libwebsocket_close_and_free_session(context, wsi,
977 LWS_CLOSE_STATUS_NOSTATUS);
981 n = recv(wsi->sock, pkt, sizeof pkt, 0);
983 libwebsocket_close_and_free_session(context, wsi,
984 LWS_CLOSE_STATUS_NOSTATUS);
985 fprintf(stderr, "ERROR reading from proxy socket\n");
990 if (strcmp(pkt, "HTTP/1.0 200 ") != 0) {
991 libwebsocket_close_and_free_session(context, wsi,
992 LWS_CLOSE_STATUS_NOSTATUS);
993 fprintf(stderr, "ERROR from proxy: %s\n", pkt);
997 /* clear his proxy connection timeout */
999 libwebsocket_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
1003 case LWS_CONNMODE_WS_CLIENT_ISSUE_HANDSHAKE:
1005 #ifdef LWS_OPENSSL_SUPPORT
1008 wsi->ssl = SSL_new(context->ssl_client_ctx);
1009 wsi->client_bio = BIO_new_socket(wsi->sock,
1011 SSL_set_bio(wsi->ssl, wsi->client_bio, wsi->client_bio);
1013 SSL_set_ex_data(wsi->ssl,
1014 openssl_websocket_private_data_index,
1017 if (SSL_connect(wsi->ssl) <= 0) {
1018 fprintf(stderr, "SSL connect error %s\n",
1019 ERR_error_string(ERR_get_error(),
1021 libwebsocket_close_and_free_session(context, wsi,
1022 LWS_CLOSE_STATUS_NOSTATUS);
1026 n = SSL_get_verify_result(wsi->ssl);
1027 if ((n != X509_V_OK) && (
1028 n != X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT ||
1029 wsi->use_ssl != 2)) {
1031 fprintf(stderr, "server's cert didn't "
1032 "look good %d\n", n);
1033 libwebsocket_close_and_free_session(context,
1034 wsi, LWS_CLOSE_STATUS_NOSTATUS);
1042 #ifdef LWS_OPENSSL_SUPPORT
1047 * create the random key
1050 n = libwebsockets_get_random(context, hash, 16);
1052 fprintf(stderr, "Unable to read from random dev %s\n",
1053 SYSTEM_RANDOM_FILEPATH);
1057 free(wsi->c_origin);
1058 if (wsi->c_protocol)
1059 free(wsi->c_protocol);
1060 libwebsocket_close_and_free_session(context, wsi,
1061 LWS_CLOSE_STATUS_NOSTATUS);
1065 lws_b64_encode_string(hash, 16, wsi->key_b64,
1066 sizeof wsi->key_b64);
1069 * 00 example client handshake
1071 * GET /socket.io/websocket HTTP/1.1
1072 * Upgrade: WebSocket
1073 * Connection: Upgrade
1074 * Host: 127.0.0.1:9999
1075 * Origin: http://127.0.0.1
1076 * Sec-WebSocket-Key1: 1 0 2#0W 9 89 7 92 ^
1077 * Sec-WebSocket-Key2: 7 7Y 4328 B2v[8(z1
1078 * Cookie: socketio=websocket
1082 * 04 example client handshake
1084 * GET /chat HTTP/1.1
1085 * Host: server.example.com
1086 * Upgrade: websocket
1087 * Connection: Upgrade
1088 * Sec-WebSocket-Key: dGhlIHNhbXBsZSBub25jZQ==
1089 * Sec-WebSocket-Origin: http://example.com
1090 * Sec-WebSocket-Protocol: chat, superchat
1091 * Sec-WebSocket-Version: 4
1094 p += sprintf(p, "GET %s HTTP/1.1\x0d\x0a", wsi->c_path);
1096 if (wsi->ietf_spec_revision == 0) {
1097 unsigned char spaces_1, spaces_2;
1098 unsigned int max_1, max_2;
1099 unsigned int num_1, num_2;
1100 unsigned long product_1, product_2;
1107 libwebsockets_get_random(context, &spaces_1,
1109 libwebsockets_get_random(context, &spaces_2,
1112 spaces_1 = (spaces_1 % 12) + 1;
1113 spaces_2 = (spaces_2 % 12) + 1;
1115 max_1 = 4294967295 / spaces_1;
1116 max_2 = 4294967295 / spaces_2;
1118 libwebsockets_get_random(context, &num_1, sizeof(int));
1119 libwebsockets_get_random(context, &num_2, sizeof(int));
1121 num_1 = (num_1 % max_1);
1122 num_2 = (num_2 % max_2);
1124 challenge[0] = num_1 >> 24;
1125 challenge[1] = num_1 >> 16;
1126 challenge[2] = num_1 >> 8;
1127 challenge[3] = num_1;
1128 challenge[4] = num_2 >> 24;
1129 challenge[5] = num_2 >> 16;
1130 challenge[6] = num_2 >> 8;
1131 challenge[7] = num_2;
1133 product_1 = num_1 * spaces_1;
1134 product_2 = num_2 * spaces_2;
1136 sprintf(key_1, "%lu", product_1);
1137 sprintf(key_2, "%lu", product_2);
1139 libwebsockets_get_random(context, &seed, sizeof(int));
1140 libwebsockets_get_random(context, &count, sizeof(int));
1142 libwebsockets_00_spam(key_1, (count % 12) + 1, seed);
1144 libwebsockets_get_random(context, &seed, sizeof(int));
1145 libwebsockets_get_random(context, &count, sizeof(int));
1147 libwebsockets_00_spam(key_2, (count % 12) + 1, seed);
1149 libwebsockets_get_random(context, &seed, sizeof(int));
1151 libwebsockets_00_spaceout(key_1, spaces_1, seed);
1152 libwebsockets_00_spaceout(key_2, spaces_2, seed >> 16);
1154 p += sprintf(p, "Upgrade: websocket\x0d\x0a"
1155 "Connection: Upgrade\x0d\x0aHost: %s\x0d\x0a",
1158 p += sprintf(p, "Origin: %s\x0d\x0a",
1161 if (wsi->c_protocol)
1162 p += sprintf(p, "Sec-WebSocket-Protocol: %s"
1163 "\x0d\x0a", wsi->c_protocol);
1165 p += sprintf(p, "Sec-WebSocket-Key1: %s\x0d\x0a",
1167 p += sprintf(p, "Sec-WebSocket-Key2: %s\x0d\x0a",
1170 /* give userland a chance to append, eg, cookies */
1172 context->protocols[0].callback(context, wsi,
1173 LWS_CALLBACK_CLIENT_APPEND_HANDSHAKE_HEADER,
1174 NULL, &p, (pkt + sizeof(pkt)) - p - 12);
1176 p += sprintf(p, "\x0d\x0a");
1178 read(context->fd_random, p, 8);
1179 memcpy(&challenge[8], p, 8);
1182 /* precompute what we want to see from the server */
1184 MD5((unsigned char *)challenge, 16,
1185 (unsigned char *)wsi->initial_handshake_hash_base64);
1190 p += sprintf(p, "Host: %s\x0d\x0a", wsi->c_host);
1191 p += sprintf(p, "Upgrade: websocket\x0d\x0a");
1192 p += sprintf(p, "Connection: Upgrade\x0d\x0a"
1193 "Sec-WebSocket-Key: ");
1194 strcpy(p, wsi->key_b64);
1195 p += strlen(wsi->key_b64);
1196 p += sprintf(p, "\x0d\x0a");
1198 p += sprintf(p, "Sec-WebSocket-Origin: %s\x0d\x0a",
1200 if (wsi->c_protocol)
1201 p += sprintf(p, "Sec-WebSocket-Protocol: %s\x0d\x0a",
1204 /* tell the server what extensions we could support */
1206 p += sprintf(p, "Sec-WebSocket-Extensions: ");
1208 ext =context->extensions;
1209 while (ext && ext->callback) {
1212 n = context->protocols[0].callback(context, wsi,
1213 LWS_CALLBACK_CLIENT_CONFIRM_EXTENSION_SUPPORTED,
1214 wsi->user_space, (char *)ext->name, 0);
1217 * zero return from callback means
1218 * go ahead and allow the extension,
1219 * it's what we get if the callback is
1232 p += sprintf(p, ext->name);
1238 p += sprintf(p, "\x0d\x0a");
1240 if (wsi->ietf_spec_revision)
1241 p += sprintf(p, "Sec-WebSocket-Version: %d\x0d\x0a",
1242 wsi->ietf_spec_revision);
1244 /* give userland a chance to append, eg, cookies */
1246 context->protocols[0].callback(context, wsi,
1247 LWS_CALLBACK_CLIENT_APPEND_HANDSHAKE_HEADER,
1248 NULL, &p, (pkt + sizeof(pkt)) - p - 12);
1250 p += sprintf(p, "\x0d\x0a");
1252 /* prepare the expected server accept response */
1254 strcpy((char *)buf, wsi->key_b64);
1255 strcpy((char *)&buf[strlen((char *)buf)], magic_websocket_guid);
1257 SHA1(buf, strlen((char *)buf), (unsigned char *)hash);
1259 lws_b64_encode_string(hash, 20,
1260 wsi->initial_handshake_hash_base64,
1261 sizeof wsi->initial_handshake_hash_base64);
1265 /* done with these now */
1270 free(wsi->c_origin);
1272 /* send our request to the server */
1274 #ifdef LWS_OPENSSL_SUPPORT
1276 n = SSL_write(wsi->ssl, pkt, p - pkt);
1279 n = send(wsi->sock, pkt, p - pkt, 0);
1282 fprintf(stderr, "ERROR writing to client socket\n");
1283 libwebsocket_close_and_free_session(context, wsi,
1284 LWS_CLOSE_STATUS_NOSTATUS);
1288 wsi->parser_state = WSI_TOKEN_NAME_PART;
1289 wsi->mode = LWS_CONNMODE_WS_CLIENT_WAITING_SERVER_REPLY;
1290 libwebsocket_set_timeout(wsi,
1291 PENDING_TIMEOUT_AWAITING_SERVER_RESPONSE, 5);
1295 case LWS_CONNMODE_WS_CLIENT_WAITING_SERVER_REPLY:
1297 /* handle server hung up on us */
1299 if (pollfd->revents & (POLLERR | POLLHUP)) {
1301 fprintf(stderr, "Server connection %p (fd=%d) dead\n",
1302 (void *)wsi, pollfd->fd);
1308 /* interpret the server response */
1311 * HTTP/1.1 101 Switching Protocols
1312 * Upgrade: websocket
1313 * Connection: Upgrade
1314 * Sec-WebSocket-Accept: me89jWimTRKTWwrS3aRrL53YZSo=
1315 * Sec-WebSocket-Nonce: AQIDBAUGBwgJCgsMDQ4PEC==
1316 * Sec-WebSocket-Protocol: chat
1319 #ifdef LWS_OPENSSL_SUPPORT
1321 len = SSL_read(wsi->ssl, pkt, sizeof pkt);
1324 len = recv(wsi->sock, pkt, sizeof pkt, 0);
1328 "libwebsocket_client_handshake read error\n");
1333 for (n = 0; n < len; n++)
1334 libwebsocket_parse(wsi, *p++);
1336 if (wsi->parser_state != WSI_PARSING_COMPLETE) {
1337 fprintf(stderr, "libwebsocket_client_handshake "
1338 "server response failed parsing\n");
1345 * HTTP/1.1 101 WebSocket Protocol Handshake
1346 * Upgrade: WebSocket
1347 * Connection: Upgrade
1348 * Sec-WebSocket-Origin: http://127.0.0.1
1349 * Sec-WebSocket-Location: ws://127.0.0.1:9999/socket.io/websocket
1354 if (wsi->ietf_spec_revision == 0) {
1355 if (!wsi->utf8_token[WSI_TOKEN_HTTP].token_len ||
1356 !wsi->utf8_token[WSI_TOKEN_UPGRADE].token_len ||
1357 !wsi->utf8_token[WSI_TOKEN_CHALLENGE].token_len ||
1358 !wsi->utf8_token[WSI_TOKEN_CONNECTION].token_len ||
1359 (!wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len &&
1360 wsi->c_protocol != NULL)) {
1361 fprintf(stderr, "libwebsocket_client_handshake "
1362 "missing required header(s)\n");
1364 fprintf(stderr, "%s", pkt);
1368 strtolower(wsi->utf8_token[WSI_TOKEN_HTTP].token);
1369 if (strcmp(wsi->utf8_token[WSI_TOKEN_HTTP].token,
1370 "101 websocket protocol handshake")) {
1371 fprintf(stderr, "libwebsocket_client_handshake "
1372 "server sent bad HTTP response '%s'\n",
1373 wsi->utf8_token[WSI_TOKEN_HTTP].token);
1377 if (wsi->utf8_token[WSI_TOKEN_CHALLENGE].token_len <
1379 fprintf(stderr, "libwebsocket_client_handshake "
1380 "challenge reply too short %d\n",
1382 WSI_TOKEN_CHALLENGE].token_len);
1384 fprintf(stderr, "%s", pkt);
1389 goto select_protocol;
1393 * well, what the server sent looked reasonable for syntax.
1394 * Now let's confirm it sent all the necessary headers
1397 if (!wsi->utf8_token[WSI_TOKEN_HTTP].token_len ||
1398 !wsi->utf8_token[WSI_TOKEN_UPGRADE].token_len ||
1399 !wsi->utf8_token[WSI_TOKEN_CONNECTION].token_len ||
1400 !wsi->utf8_token[WSI_TOKEN_ACCEPT].token_len ||
1401 (!wsi->utf8_token[WSI_TOKEN_NONCE].token_len &&
1402 wsi->ietf_spec_revision == 4) ||
1403 (!wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len &&
1404 wsi->c_protocol != NULL)) {
1405 fprintf(stderr, "libwebsocket_client_handshake "
1406 "missing required header(s)\n");
1408 fprintf(stderr, "%s", pkt);
1413 * Everything seems to be there, now take a closer look at what
1417 strtolower(wsi->utf8_token[WSI_TOKEN_HTTP].token);
1418 if (strcmp(wsi->utf8_token[WSI_TOKEN_HTTP].token,
1419 "101 switching protocols")) {
1420 fprintf(stderr, "libwebsocket_client_handshake "
1421 "server sent bad HTTP response '%s'\n",
1422 wsi->utf8_token[WSI_TOKEN_HTTP].token);
1426 strtolower(wsi->utf8_token[WSI_TOKEN_UPGRADE].token);
1427 if (strcmp(wsi->utf8_token[WSI_TOKEN_UPGRADE].token,
1429 fprintf(stderr, "libwebsocket_client_handshake server "
1430 "sent bad Upgrade header '%s'\n",
1431 wsi->utf8_token[WSI_TOKEN_UPGRADE].token);
1435 strtolower(wsi->utf8_token[WSI_TOKEN_CONNECTION].token);
1436 if (strcmp(wsi->utf8_token[WSI_TOKEN_CONNECTION].token,
1438 fprintf(stderr, "libwebsocket_client_handshake server "
1439 "sent bad Connection hdr '%s'\n",
1440 wsi->utf8_token[WSI_TOKEN_CONNECTION].token);
1445 pc = wsi->c_protocol;
1448 * confirm the protocol the server wants to talk was in the list
1449 * of protocols we offered
1452 if (!wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len) {
1455 * no protocol name to work from,
1456 * default to first protocol
1458 wsi->protocol = &context->protocols[0];
1460 free(wsi->c_protocol);
1465 while (*pc && !okay) {
1467 wsi->utf8_token[WSI_TOKEN_PROTOCOL].token,
1468 wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len)) &&
1469 (pc[wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len] == ',' ||
1470 pc[wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len] == '\0')) {
1474 while (*pc && *pc != ',')
1476 while (*pc && *pc != ' ')
1480 /* done with him now */
1482 if (wsi->c_protocol)
1483 free(wsi->c_protocol);
1487 fprintf(stderr, "libwebsocket_client_handshake server "
1488 "sent bad protocol '%s'\n",
1489 wsi->utf8_token[WSI_TOKEN_PROTOCOL].token);
1494 * identify the selected protocol struct and set it
1497 wsi->protocol = NULL;
1498 while (context->protocols[n].callback) {
1499 if (strcmp(wsi->utf8_token[WSI_TOKEN_PROTOCOL].token,
1500 context->protocols[n].name) == 0)
1501 wsi->protocol = &context->protocols[n];
1505 if (wsi->protocol == NULL) {
1506 fprintf(stderr, "libwebsocket_client_handshake server "
1507 "requested protocol '%s', which we "
1508 "said we supported but we don't!\n",
1509 wsi->utf8_token[WSI_TOKEN_PROTOCOL].token);
1514 /* instantiate the accepted extensions */
1516 if (!wsi->utf8_token[WSI_TOKEN_EXTENSIONS].token_len)
1520 * break down the list of server accepted extensions
1521 * and go through matching them or identifying bogons
1524 c = wsi->utf8_token[WSI_TOKEN_EXTENSIONS].token;
1528 if (*c && *c != ',') {
1530 if (n < sizeof(ext_name) - 1)
1538 /* check we actually support it */
1541 ext = wsi->protocol->owning_server->extensions;
1542 while (ext && ext->callback) {
1544 if (strcmp(ext_name, ext->name)) {
1551 /* instantiate the extension on this conn */
1553 wsi->active_extensions_user[
1554 wsi->count_active_extensions] =
1555 malloc(ext->per_session_data_size);
1556 wsi->active_extensions[
1557 wsi->count_active_extensions] = ext;
1559 /* allow him to construct his context */
1561 ext->callback(wsi->protocol->owning_server,
1562 wsi, LWS_EXT_CALLBACK_CLIENT_CONSTRUCT,
1563 wsi->active_extensions_user[
1564 wsi->count_active_extensions], NULL, 0);
1566 wsi->count_active_extensions++;
1572 fprintf(stderr, "Server said we should use"
1573 "an unknown extension '%s'!\n", ext_name);
1583 if (wsi->ietf_spec_revision == 0) {
1585 if (memcmp(wsi->initial_handshake_hash_base64,
1586 wsi->utf8_token[WSI_TOKEN_CHALLENGE].token, 16)) {
1587 fprintf(stderr, "libwebsocket_client_handshake "
1588 "failed 00 challenge compare\n");
1590 fprintf(stderr, "%s", pkt);
1598 * Confirm his accept token is the one we precomputed
1601 if (strcmp(wsi->utf8_token[WSI_TOKEN_ACCEPT].token,
1602 wsi->initial_handshake_hash_base64)) {
1603 fprintf(stderr, "libwebsocket_client_handshake server "
1604 "sent bad ACCEPT '%s' vs computed '%s'\n",
1605 wsi->utf8_token[WSI_TOKEN_ACCEPT].token,
1606 wsi->initial_handshake_hash_base64);
1610 if (wsi->ietf_spec_revision == 4) {
1612 * Calculate the 04 masking key to use when
1613 * sending data to server
1616 strcpy((char *)buf, wsi->key_b64);
1617 p = (char *)buf + strlen(wsi->key_b64);
1618 strcpy(p, wsi->utf8_token[WSI_TOKEN_NONCE].token);
1619 p += wsi->utf8_token[WSI_TOKEN_NONCE].token_len;
1620 strcpy(p, magic_websocket_04_masking_guid);
1621 SHA1(buf, strlen((char *)buf), wsi->masking_key_04);
1625 /* allocate the per-connection user memory (if any) */
1627 if (wsi->protocol->per_session_data_size) {
1628 wsi->user_space = malloc(
1629 wsi->protocol->per_session_data_size);
1630 if (wsi->user_space == NULL) {
1631 fprintf(stderr, "Out of memory for "
1632 "conn user space\n");
1636 wsi->user_space = NULL;
1638 /* clear his proxy connection timeout */
1640 libwebsocket_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
1642 /* mark him as being alive */
1644 wsi->state = WSI_STATE_ESTABLISHED;
1645 wsi->mode = LWS_CONNMODE_WS_CLIENT;
1647 fprintf(stderr, "handshake OK for protocol %s\n",
1648 wsi->protocol->name);
1650 /* call him back to inform him he is up */
1652 wsi->protocol->callback(context, wsi,
1653 LWS_CALLBACK_CLIENT_ESTABLISHED,
1660 if (wsi->c_protocol)
1661 free(wsi->c_protocol);
1664 libwebsocket_close_and_free_session(context, wsi,
1665 LWS_CLOSE_STATUS_NOSTATUS);
1669 case LWS_CONNMODE_WS_SERVING:
1670 case LWS_CONNMODE_WS_CLIENT:
1672 /* handle session socket closed */
1674 if (pollfd->revents & (POLLERR | POLLHUP)) {
1676 fprintf(stderr, "Session Socket %p (fd=%d) dead\n",
1677 (void *)wsi, pollfd->fd);
1679 libwebsocket_close_and_free_session(context, wsi,
1680 LWS_CLOSE_STATUS_NOSTATUS);
1684 /* the guy requested a callback when it was OK to write */
1686 if ((pollfd->revents & POLLOUT) &&
1687 wsi->state == WSI_STATE_ESTABLISHED)
1688 if (lws_handle_POLLOUT_event(context, wsi,
1690 libwebsocket_close_and_free_session(
1691 context, wsi, LWS_CLOSE_STATUS_NORMAL);
1696 /* any incoming data ready? */
1698 if (!(pollfd->revents & POLLIN))
1701 #ifdef LWS_OPENSSL_SUPPORT
1703 eff_buf.token_len = SSL_read(wsi->ssl, buf, sizeof buf);
1707 recv(pollfd->fd, buf, sizeof buf, 0);
1709 if (eff_buf.token_len < 0) {
1710 fprintf(stderr, "Socket read returned %d\n",
1714 if (!eff_buf.token_len) {
1715 libwebsocket_close_and_free_session(context, wsi,
1716 LWS_CLOSE_STATUS_NOSTATUS);
1721 * give any active extensions a chance to munge the buffer
1722 * before parse. We pass in a pointer to an lws_tokens struct
1723 * prepared with the default buffer and content length that's in
1724 * there. Rather than rewrite the default buffer, extensions
1725 * that expect to grow the buffer can adapt .token to
1726 * point to their own per-connection buffer in the extension
1727 * user allocation. By default with no extensions or no
1728 * extension callback handling, just the normal input buffer is
1729 * used then so it is efficient.
1732 eff_buf.token = (char *)buf;
1739 for (n = 0; n < wsi->count_active_extensions; n++) {
1740 m = wsi->active_extensions[n]->callback(context, wsi,
1741 LWS_EXT_CALLBACK_PACKET_RX_PREPARSE,
1742 wsi->active_extensions_user[n], &eff_buf, 0);
1744 fprintf(stderr, "Extension reports fatal error\n");
1745 libwebsocket_close_and_free_session(context, wsi,
1746 LWS_CLOSE_STATUS_NOSTATUS);
1753 /* service incoming data */
1755 if (eff_buf.token_len) {
1756 n = libwebsocket_read(context, wsi,
1757 (unsigned char *)eff_buf.token, eff_buf.token_len);
1763 eff_buf.token = NULL;
1764 eff_buf.token_len = 0;
1774 * libwebsocket_context_destroy() - Destroy the websocket context
1775 * @context: Websocket context
1777 * This function closes any active connections and then frees the
1778 * context. After calling this, any further use of the context is
1782 libwebsocket_context_destroy(struct libwebsocket_context *context)
1786 struct libwebsocket *wsi;
1788 for (n = 0; n < FD_HASHTABLE_MODULUS; n++)
1789 for (m = 0; m < context->fd_hashtable[n].length; m++) {
1790 wsi = context->fd_hashtable[n].wsi[m];
1791 libwebsocket_close_and_free_session(context, wsi,
1792 LWS_CLOSE_STATUS_GOINGAWAY);
1797 close(context->fd_random);
1800 #ifdef LWS_OPENSSL_SUPPORT
1801 if (context->ssl_ctx)
1802 SSL_CTX_free(context->ssl_ctx);
1803 if (context->ssl_client_ctx)
1804 SSL_CTX_free(context->ssl_client_ctx);
1815 * libwebsocket_service() - Service any pending websocket activity
1816 * @context: Websocket context
1817 * @timeout_ms: Timeout for poll; 0 means return immediately if nothing needed
1818 * service otherwise block and service immediately, returning
1819 * after the timeout if nothing needed service.
1821 * This function deals with any pending websocket traffic, for three
1822 * kinds of event. It handles these events on both server and client
1823 * types of connection the same.
1825 * 1) Accept new connections to our context's server
1827 * 2) Perform pending broadcast writes initiated from other forked
1828 * processes (effectively serializing asynchronous broadcasts)
1830 * 3) Call the receive callback for incoming frame data received by
1831 * server or client connections.
1833 * You need to call this service function periodically to all the above
1834 * functions to happen; if your application is single-threaded you can
1835 * just call it in your main event loop.
1837 * Alternatively you can fork a new process that asynchronously handles
1838 * calling this service in a loop. In that case you are happy if this
1839 * call blocks your thread until it needs to take care of something and
1840 * would call it with a large nonzero timeout. Your loop then takes no
1841 * CPU while there is nothing happening.
1843 * If you are calling it in a single-threaded app, you don't want it to
1844 * wait around blocking other things in your loop from happening, so you
1845 * would call it with a timeout_ms of 0, so it returns immediately if
1846 * nothing is pending, or as soon as it services whatever was pending.
1851 libwebsocket_service(struct libwebsocket_context *context, int timeout_ms)
1855 /* stay dead once we are dead */
1857 if (context == NULL)
1860 /* wait for something to need service */
1862 n = poll(context->fds, context->fds_count, timeout_ms);
1863 if (n == 0) /* poll timeout */
1868 fprintf(stderr, "Listen Socket dead\n");
1873 /* handle accept on listening socket? */
1875 for (n = 0; n < context->fds_count; n++)
1876 if (context->fds[n].revents)
1877 libwebsocket_service_fd(context, &context->fds[n]);
1883 * libwebsocket_callback_on_writable() - Request a callback when this socket
1884 * becomes able to be written to without
1887 * @context: libwebsockets context
1888 * @wsi: Websocket connection instance to get callback for
1892 libwebsocket_callback_on_writable(struct libwebsocket_context *context,
1893 struct libwebsocket *wsi)
1897 for (n = 0; n < context->fds_count; n++)
1898 if (context->fds[n].fd == wsi->sock) {
1899 context->fds[n].events |= POLLOUT;
1900 n = context->fds_count;
1903 /* external POLL support via protocol 0 */
1904 context->protocols[0].callback(context, wsi,
1905 LWS_CALLBACK_SET_MODE_POLL_FD,
1906 (void *)(long)wsi->sock, NULL, POLLOUT);
1912 * libwebsocket_callback_on_writable_all_protocol() - Request a callback for
1913 * all connections using the given protocol when it
1914 * becomes possible to write to each socket without
1917 * @protocol: Protocol whose connections will get callbacks
1921 libwebsocket_callback_on_writable_all_protocol(
1922 const struct libwebsocket_protocols *protocol)
1924 struct libwebsocket_context *context = protocol->owning_server;
1927 struct libwebsocket *wsi;
1929 for (n = 0; n < FD_HASHTABLE_MODULUS; n++) {
1931 for (m = 0; m < context->fd_hashtable[n].length; m++) {
1933 wsi = context->fd_hashtable[n].wsi[m];
1935 if (wsi->protocol == protocol)
1936 libwebsocket_callback_on_writable(context, wsi);
1944 * libwebsocket_set_timeout() - marks the wsi as subject to a timeout
1946 * You will not need this unless you are doing something special
1948 * @wsi: Websocket connection instance
1949 * @reason: timeout reason
1950 * @secs: how many seconds
1954 libwebsocket_set_timeout(struct libwebsocket *wsi,
1955 enum pending_timeout reason, int secs)
1959 gettimeofday(&tv, NULL);
1961 wsi->pending_timeout_limit = tv.tv_sec + secs;
1962 wsi->pending_timeout = reason;
1967 * libwebsocket_get_socket_fd() - returns the socket file descriptor
1969 * You will not need this unless you are doing something special
1971 * @wsi: Websocket connection instance
1975 libwebsocket_get_socket_fd(struct libwebsocket *wsi)
1981 * libwebsocket_rx_flow_control() - Enable and disable socket servicing for
1982 * receieved packets.
1984 * If the output side of a server process becomes choked, this allows flow
1985 * control for the input side.
1987 * @wsi: Websocket connection instance to get callback for
1988 * @enable: 0 = disable read servicing for this connection, 1 = enable
1992 libwebsocket_rx_flow_control(struct libwebsocket *wsi, int enable)
1994 struct libwebsocket_context *context = wsi->protocol->owning_server;
1997 for (n = 0; n < context->fds_count; n++)
1998 if (context->fds[n].fd == wsi->sock) {
2000 context->fds[n].events |= POLLIN;
2002 context->fds[n].events &= ~POLLIN;
2008 /* external POLL support via protocol 0 */
2009 context->protocols[0].callback(context, wsi,
2010 LWS_CALLBACK_SET_MODE_POLL_FD,
2011 (void *)(long)wsi->sock, NULL, POLLIN);
2013 /* external POLL support via protocol 0 */
2014 context->protocols[0].callback(context, wsi,
2015 LWS_CALLBACK_CLEAR_MODE_POLL_FD,
2016 (void *)(long)wsi->sock, NULL, POLLIN);
2019 fprintf(stderr, "libwebsocket_callback_on_writable "
2020 "unable to find socket\n");
2025 * libwebsocket_canonical_hostname() - returns this host's hostname
2027 * This is typically used by client code to fill in the host parameter
2028 * when making a client connection. You can only call it after the context
2031 * @context: Websocket context
2036 libwebsocket_canonical_hostname(struct libwebsocket_context *context)
2038 return (const char *)context->canonical_hostname;
2042 static void sigpipe_handler(int x)
2046 #ifdef LWS_OPENSSL_SUPPORT
2048 OpenSSL_verify_callback(int preverify_ok, X509_STORE_CTX *x509_ctx)
2053 struct libwebsocket_context *context;
2055 ssl = X509_STORE_CTX_get_ex_data(x509_ctx,
2056 SSL_get_ex_data_X509_STORE_CTX_idx());
2059 * !!! nasty openssl requires the index to come as a library-scope
2062 context = SSL_get_ex_data(ssl, openssl_websocket_private_data_index);
2064 n = context->protocols[0].callback(NULL, NULL,
2065 LWS_CALLBACK_OPENSSL_PERFORM_CLIENT_CERT_VERIFICATION,
2066 x509_ctx, ssl, preverify_ok);
2068 /* convert return code from 0 = OK to 1 = OK */
2081 * libwebsocket_create_context() - Create the websocket handler
2082 * @port: Port to listen on... you can use 0 to suppress listening on
2083 * any port, that's what you want if you are not running a
2084 * websocket server at all but just using it as a client
2085 * @interf: NULL to bind the listen socket to all interfaces, or the
2086 * interface name, eg, "eth2"
2087 * @protocols: Array of structures listing supported protocols and a protocol-
2088 * specific callback for each one. The list is ended with an
2089 * entry that has a NULL callback pointer.
2090 * It's not const because we write the owning_server member
2091 * @extensions: NULL or array of libwebsocket_extension structs listing the
2092 * extensions this context supports
2093 * @ssl_cert_filepath: If libwebsockets was compiled to use ssl, and you want
2094 * to listen using SSL, set to the filepath to fetch the
2095 * server cert from, otherwise NULL for unencrypted
2096 * @ssl_private_key_filepath: filepath to private key if wanting SSL mode,
2098 * @gid: group id to change to after setting listen socket, or -1.
2099 * @uid: user id to change to after setting listen socket, or -1.
2100 * @options: 0, or LWS_SERVER_OPTION_DEFEAT_CLIENT_MASK
2102 * This function creates the listening socket and takes care
2103 * of all initialization in one step.
2105 * After initialization, it returns a struct libwebsocket_context * that
2106 * represents this server. After calling, user code needs to take care
2107 * of calling libwebsocket_service() with the context pointer to get the
2108 * server's sockets serviced. This can be done in the same process context
2109 * or a forked process, or another thread,
2111 * The protocol callback functions are called for a handful of events
2112 * including http requests coming in, websocket connections becoming
2113 * established, and data arriving; it's also called periodically to allow
2114 * async transmission.
2116 * HTTP requests are sent always to the FIRST protocol in @protocol, since
2117 * at that time websocket protocol has not been negotiated. Other
2118 * protocols after the first one never see any HTTP callack activity.
2120 * The server created is a simple http server by default; part of the
2121 * websocket standard is upgrading this http connection to a websocket one.
2123 * This allows the same server to provide files like scripts and favicon /
2124 * images or whatever over http and dynamic data over websockets all in
2125 * one place; they're all handled in the user callback.
2128 struct libwebsocket_context *
2129 libwebsocket_create_context(int port, const char *interf,
2130 struct libwebsocket_protocols *protocols,
2131 struct libwebsocket_extension *extensions,
2132 const char *ssl_cert_filepath,
2133 const char *ssl_private_key_filepath,
2134 int gid, int uid, unsigned int options)
2139 struct sockaddr_in serv_addr, cli_addr;
2141 struct libwebsocket_context *context = NULL;
2144 char hostname[1024];
2146 struct libwebsocket *wsi;
2148 #ifdef LWS_OPENSSL_SUPPORT
2150 char ssl_err_buf[512];
2155 WORD wVersionRequested;
2159 /* Use the MAKEWORD(lowbyte, highbyte) macro from Windef.h */
2160 wVersionRequested = MAKEWORD(2, 2);
2162 err = WSAStartup(wVersionRequested, &wsaData);
2164 /* Tell the user that we could not find a usable */
2166 fprintf(stderr, "WSAStartup failed with error: %d\n",
2174 context = malloc(sizeof(struct libwebsocket_context));
2176 fprintf(stderr, "No memory for websocket context\n");
2179 context->protocols = protocols;
2180 context->listen_port = port;
2181 context->http_proxy_port = 0;
2182 context->http_proxy_address[0] = '\0';
2183 context->options = options;
2184 context->fds_count = 0;
2185 context->extensions = extensions;
2188 context->fd_random = 0;
2190 context->fd_random = open(SYSTEM_RANDOM_FILEPATH, O_RDONLY);
2191 if (context->fd_random < 0) {
2192 fprintf(stderr, "Unable to open random device %s %d\n",
2193 SYSTEM_RANDOM_FILEPATH, context->fd_random);
2198 #ifdef LWS_OPENSSL_SUPPORT
2199 context->use_ssl = 0;
2200 context->ssl_ctx = NULL;
2201 context->ssl_client_ctx = NULL;
2202 openssl_websocket_private_data_index = 0;
2204 /* find canonical hostname */
2206 hostname[(sizeof hostname) - 1] = '\0';
2207 gethostname(hostname, (sizeof hostname) - 1);
2208 he = gethostbyname(hostname);
2210 strncpy(context->canonical_hostname, he->h_name,
2211 sizeof context->canonical_hostname - 1);
2212 context->canonical_hostname[
2213 sizeof context->canonical_hostname - 1] = '\0';
2215 strncpy(context->canonical_hostname, hostname,
2216 sizeof context->canonical_hostname - 1);
2218 /* split the proxy ads:port if given */
2220 p = getenv("http_proxy");
2222 strncpy(context->http_proxy_address, p,
2223 sizeof context->http_proxy_address - 1);
2224 context->http_proxy_address[
2225 sizeof context->http_proxy_address - 1] = '\0';
2227 p = strchr(context->http_proxy_address, ':');
2229 fprintf(stderr, "http_proxy needs to be ads:port\n");
2233 context->http_proxy_port = atoi(p + 1);
2235 fprintf(stderr, "Using proxy %s:%u\n",
2236 context->http_proxy_address,
2237 context->http_proxy_port);
2242 #ifdef LWS_OPENSSL_SUPPORT
2243 context->use_ssl = ssl_cert_filepath != NULL &&
2244 ssl_private_key_filepath != NULL;
2245 if (context->use_ssl)
2246 fprintf(stderr, " Compiled with SSL support, "
2249 fprintf(stderr, " Compiled with SSL support, "
2253 if (ssl_cert_filepath != NULL &&
2254 ssl_private_key_filepath != NULL) {
2255 fprintf(stderr, " Not compiled for OpenSSl support!\n");
2258 fprintf(stderr, " Compiled without SSL support, "
2259 "serving unencrypted\n");
2263 /* ignore SIGPIPE */
2266 signal(SIGPIPE, sigpipe_handler);
2270 #ifdef LWS_OPENSSL_SUPPORT
2272 /* basic openssl init */
2276 OpenSSL_add_all_algorithms();
2277 SSL_load_error_strings();
2279 openssl_websocket_private_data_index =
2280 SSL_get_ex_new_index(0, "libwebsockets", NULL, NULL, NULL);
2283 * Firefox insists on SSLv23 not SSLv3
2284 * Konq disables SSLv2 by default now, SSLv23 works
2287 method = (SSL_METHOD *)SSLv23_server_method();
2289 fprintf(stderr, "problem creating ssl method: %s\n",
2290 ERR_error_string(ERR_get_error(), ssl_err_buf));
2293 context->ssl_ctx = SSL_CTX_new(method); /* create context */
2294 if (!context->ssl_ctx) {
2295 fprintf(stderr, "problem creating ssl context: %s\n",
2296 ERR_error_string(ERR_get_error(), ssl_err_buf));
2300 /* client context */
2301 if (port == CONTEXT_PORT_NO_LISTEN)
2303 method = (SSL_METHOD *)SSLv23_client_method();
2305 fprintf(stderr, "problem creating ssl method: %s\n",
2306 ERR_error_string(ERR_get_error(), ssl_err_buf));
2309 /* create context */
2310 context->ssl_client_ctx = SSL_CTX_new(method);
2311 if (!context->ssl_client_ctx) {
2312 fprintf(stderr, "problem creating ssl context: %s\n",
2313 ERR_error_string(ERR_get_error(), ssl_err_buf));
2317 /* openssl init for cert verification (for client sockets) */
2319 if (!SSL_CTX_load_verify_locations(
2320 context->ssl_client_ctx, NULL,
2321 LWS_OPENSSL_CLIENT_CERTS))
2323 "Unable to load SSL Client certs from %s "
2324 "(set by --with-client-cert-dir= in configure) -- "
2325 " client ssl isn't going to work",
2326 LWS_OPENSSL_CLIENT_CERTS);
2329 * callback allowing user code to load extra verification certs
2330 * helping the client to verify server identity
2333 context->protocols[0].callback(context, NULL,
2334 LWS_CALLBACK_OPENSSL_LOAD_EXTRA_CLIENT_VERIFY_CERTS,
2335 context->ssl_client_ctx, NULL, 0);
2337 /* as a server, are we requiring clients to identify themselves? */
2339 if (options & LWS_SERVER_OPTION_REQUIRE_VALID_OPENSSL_CLIENT_CERT) {
2341 /* absolutely require the client cert */
2343 SSL_CTX_set_verify(context->ssl_ctx,
2344 SSL_VERIFY_PEER | SSL_VERIFY_FAIL_IF_NO_PEER_CERT,
2345 OpenSSL_verify_callback);
2348 * give user code a chance to load certs into the server
2349 * allowing it to verify incoming client certs
2352 context->protocols[0].callback(context, NULL,
2353 LWS_CALLBACK_OPENSSL_LOAD_EXTRA_SERVER_VERIFY_CERTS,
2354 context->ssl_ctx, NULL, 0);
2357 if (context->use_ssl) {
2359 /* openssl init for server sockets */
2361 /* set the local certificate from CertFile */
2362 n = SSL_CTX_use_certificate_file(context->ssl_ctx,
2363 ssl_cert_filepath, SSL_FILETYPE_PEM);
2365 fprintf(stderr, "problem getting cert '%s': %s\n",
2367 ERR_error_string(ERR_get_error(), ssl_err_buf));
2370 /* set the private key from KeyFile */
2371 if (SSL_CTX_use_PrivateKey_file(context->ssl_ctx,
2372 ssl_private_key_filepath, SSL_FILETYPE_PEM) != 1) {
2373 fprintf(stderr, "ssl problem getting key '%s': %s\n",
2374 ssl_private_key_filepath,
2375 ERR_error_string(ERR_get_error(), ssl_err_buf));
2378 /* verify private key */
2379 if (!SSL_CTX_check_private_key(context->ssl_ctx)) {
2380 fprintf(stderr, "Private SSL key doesn't match cert\n");
2384 /* SSL is happy and has a cert it's content with */
2390 if (lws_b64_selftest())
2393 /* fd hashtable init */
2395 for (n = 0; n < FD_HASHTABLE_MODULUS; n++)
2396 context->fd_hashtable[n].length = 0;
2398 /* set up our external listening socket we serve on */
2402 sockfd = socket(AF_INET, SOCK_STREAM, 0);
2404 fprintf(stderr, "ERROR opening socket");
2408 /* allow us to restart even if old sockets in TIME_WAIT */
2409 setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt));
2411 bzero((char *) &serv_addr, sizeof(serv_addr));
2412 serv_addr.sin_family = AF_INET;
2414 serv_addr.sin_addr.s_addr = INADDR_ANY;
2416 interface_to_sa(interf, &serv_addr,
2418 serv_addr.sin_port = htons(port);
2420 n = bind(sockfd, (struct sockaddr *) &serv_addr,
2423 fprintf(stderr, "ERROR on binding to port %d (%d %d)\n",
2428 wsi = malloc(sizeof(struct libwebsocket));
2429 memset(wsi, 0, sizeof (struct libwebsocket));
2431 wsi->count_active_extensions = 0;
2432 wsi->mode = LWS_CONNMODE_SERVER_LISTENER;
2433 insert_wsi(context, wsi);
2436 fprintf(stderr, " Listening on port %d\n", port);
2438 /* list in the internal poll array */
2440 context->fds[context->fds_count].fd = sockfd;
2441 context->fds[context->fds_count++].events = POLLIN;
2443 /* external POLL support via protocol 0 */
2444 context->protocols[0].callback(context, wsi,
2445 LWS_CALLBACK_ADD_POLL_FD,
2446 (void *)(long)sockfd, NULL, POLLIN);
2450 /* drop any root privs for this process */
2455 fprintf(stderr, "setgid: %s\n", strerror(errno));
2458 fprintf(stderr, "setuid: %s\n", strerror(errno));
2461 /* set up our internal broadcast trigger sockets per-protocol */
2463 for (context->count_protocols = 0;
2464 protocols[context->count_protocols].callback;
2465 context->count_protocols++) {
2466 protocols[context->count_protocols].owning_server = context;
2467 protocols[context->count_protocols].protocol_index =
2468 context->count_protocols;
2470 fd = socket(AF_INET, SOCK_STREAM, 0);
2472 fprintf(stderr, "ERROR opening socket");
2476 /* allow us to restart even if old sockets in TIME_WAIT */
2477 setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt));
2479 bzero((char *) &serv_addr, sizeof(serv_addr));
2480 serv_addr.sin_family = AF_INET;
2481 serv_addr.sin_addr.s_addr = inet_addr("127.0.0.1");
2482 serv_addr.sin_port = 0; /* pick the port for us */
2484 n = bind(fd, (struct sockaddr *) &serv_addr, sizeof(serv_addr));
2486 fprintf(stderr, "ERROR on binding to port %d (%d %d)\n",
2491 slen = sizeof cli_addr;
2492 n = getsockname(fd, (struct sockaddr *)&cli_addr, &slen);
2494 fprintf(stderr, "getsockname failed\n");
2497 protocols[context->count_protocols].broadcast_socket_port =
2498 ntohs(cli_addr.sin_port);
2501 debug(" Protocol %s broadcast socket %d\n",
2502 protocols[context->count_protocols].name,
2503 ntohs(cli_addr.sin_port));
2505 /* dummy wsi per broadcast proxy socket */
2507 wsi = malloc(sizeof(struct libwebsocket));
2508 memset(wsi, 0, sizeof (struct libwebsocket));
2510 wsi->mode = LWS_CONNMODE_BROADCAST_PROXY_LISTENER;
2511 wsi->count_active_extensions = 0;
2512 /* note which protocol we are proxying */
2513 wsi->protocol_index_for_broadcast_proxy =
2514 context->count_protocols;
2515 insert_wsi(context, wsi);
2517 /* list in internal poll array */
2519 context->fds[context->fds_count].fd = fd;
2520 context->fds[context->fds_count].events = POLLIN;
2521 context->fds[context->fds_count].revents = 0;
2522 context->fds_count++;
2524 /* external POLL support via protocol 0 */
2525 context->protocols[0].callback(context, wsi,
2526 LWS_CALLBACK_ADD_POLL_FD,
2527 (void *)(long)fd, NULL, POLLIN);
2537 * libwebsockets_fork_service_loop() - Optional helper function forks off
2538 * a process for the websocket server loop.
2539 * You don't have to use this but if not, you
2540 * have to make sure you are calling
2541 * libwebsocket_service periodically to service
2542 * the websocket traffic
2543 * @context: server context returned by creation function
2547 libwebsockets_fork_service_loop(struct libwebsocket_context *context)
2550 struct sockaddr_in cli_addr;
2560 /* main process context */
2563 * set up the proxy sockets to allow broadcast from
2564 * service process context
2567 for (p = 0; p < context->count_protocols; p++) {
2568 fd = socket(AF_INET, SOCK_STREAM, 0);
2570 fprintf(stderr, "Unable to create socket\n");
2573 cli_addr.sin_family = AF_INET;
2574 cli_addr.sin_port = htons(
2575 context->protocols[p].broadcast_socket_port);
2576 cli_addr.sin_addr.s_addr = inet_addr("127.0.0.1");
2577 n = connect(fd, (struct sockaddr *)&cli_addr,
2580 fprintf(stderr, "Unable to connect to "
2581 "broadcast socket %d, %s\n",
2582 n, strerror(errno));
2586 context->protocols[p].broadcast_socket_user_fd = fd;
2592 /* we want a SIGHUP when our parent goes down */
2593 prctl(PR_SET_PDEATHSIG, SIGHUP);
2595 /* in this forked process, sit and service websocket connections */
2598 if (libwebsocket_service(context, 1000))
2607 * libwebsockets_get_protocol() - Returns a protocol pointer from a websocket
2609 * @wsi: pointer to struct websocket you want to know the protocol of
2612 * This is useful to get the protocol to broadcast back to from inside
2616 const struct libwebsocket_protocols *
2617 libwebsockets_get_protocol(struct libwebsocket *wsi)
2619 return wsi->protocol;
2623 * libwebsockets_broadcast() - Sends a buffer to the callback for all active
2624 * connections of the given protocol.
2625 * @protocol: pointer to the protocol you will broadcast to all members of
2626 * @buf: buffer containing the data to be broadcase. NOTE: this has to be
2627 * allocated with LWS_SEND_BUFFER_PRE_PADDING valid bytes before
2628 * the pointer and LWS_SEND_BUFFER_POST_PADDING afterwards in the
2629 * case you are calling this function from callback context.
2630 * @len: length of payload data in buf, starting from buf.
2632 * This function allows bulk sending of a packet to every connection using
2633 * the given protocol. It does not send the data directly; instead it calls
2634 * the callback with a reason type of LWS_CALLBACK_BROADCAST. If the callback
2635 * wants to actually send the data for that connection, the callback itself
2636 * should call libwebsocket_write().
2638 * libwebsockets_broadcast() can be called from another fork context without
2639 * having to take any care about data visibility between the processes, it'll
2645 libwebsockets_broadcast(const struct libwebsocket_protocols *protocol,
2646 unsigned char *buf, size_t len)
2648 struct libwebsocket_context *context = protocol->owning_server;
2651 struct libwebsocket * wsi;
2653 if (!protocol->broadcast_socket_user_fd) {
2655 * We are either running unforked / flat, or we are being
2656 * called from poll thread context
2657 * eg, from a callback. In that case don't use sockets for
2658 * broadcast IPC (since we can't open a socket connection to
2659 * a socket listening on our own thread) but directly do the
2662 * Locking is not needed because we are by definition being
2663 * called in the poll thread context and are serialized.
2666 for (n = 0; n < FD_HASHTABLE_MODULUS; n++) {
2668 for (m = 0; m < context->fd_hashtable[n].length; m++) {
2670 wsi = context->fd_hashtable[n].wsi[m];
2672 if (wsi->mode != LWS_CONNMODE_WS_SERVING)
2676 * never broadcast to
2677 * non-established connections
2679 if (wsi->state != WSI_STATE_ESTABLISHED)
2682 /* only broadcast to guys using
2683 * requested protocol
2685 if (wsi->protocol != protocol)
2688 wsi->protocol->callback(context, wsi,
2689 LWS_CALLBACK_BROADCAST,
2699 * We're being called from a different process context than the server
2700 * loop. Instead of broadcasting directly, we send our
2701 * payload on a socket to do the IPC; the server process will serialize
2702 * the broadcast action in its main poll() loop.
2704 * There's one broadcast socket listening for each protocol supported
2705 * set up when the websocket server initializes
2708 n = send(protocol->broadcast_socket_user_fd, buf, len, MSG_NOSIGNAL);