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);
431 libwebsockets_SHA1(const unsigned char *d, size_t n, unsigned char *md)
433 return SHA1(d, n, md);
436 void libwebsockets_00_spaceout(char *key, int spaces, int seed)
442 if (*key && (seed & 1))
446 p = key + strlen(key);
455 void libwebsockets_00_spam(char *key, int count, int seed)
462 if (*key && (seed & 1))
466 p = key + strlen(key);
471 *key++ = 0x21 + ((seed & 0xffff) % 15);
472 /* 4 would use it up too fast.. not like it matters */
477 int lws_send_pipe_choked(struct libwebsocket *wsi)
482 fds.events = POLLOUT;
485 if (poll(&fds, 1, 0) != 1)
488 if ((fds.revents & POLLOUT) == 0)
491 /* okay to send another packet without blocking */
497 lws_handle_POLLOUT_event(struct libwebsocket_context *context,
498 struct libwebsocket *wsi, struct pollfd *pollfd)
500 struct lws_tokens eff_buf;
505 if (!wsi->extension_data_pending)
509 * check in on the active extensions, see if they
510 * had pending stuff to spill... they need to get the
511 * first look-in otherwise sequence will be disordered
513 * NULL, zero-length eff_buf means just spill pending
519 /* default to nobody has more to spill */
522 eff_buf.token = NULL;
523 eff_buf.token_len = 0;
525 /* give every extension a chance to spill */
527 for (n = 0; n < wsi->count_active_extensions; n++) {
528 m = wsi->active_extensions[n]->callback(
529 wsi->protocol->owning_server, wsi,
530 LWS_EXT_CALLBACK_PACKET_TX_PRESEND,
531 wsi->active_extensions_user[n], &eff_buf, 0);
533 fprintf(stderr, "extension reports fatal error\n");
538 * at least one extension told us he has more
539 * to spill, so we will go around again after
544 /* assuming they gave us something to send, send it */
546 if (eff_buf.token_len) {
547 if (lws_issue_raw(wsi, (unsigned char *)eff_buf.token,
553 /* no extension has more to spill */
559 * There's more to spill from an extension, but we just sent
560 * something... did that leave the pipe choked?
563 if (!lws_send_pipe_choked(wsi))
564 /* no we could add more */
567 fprintf(stderr, "choked in POLLOUT service\n");
570 * Yes, he's choked. Leave the POLLOUT masked on so we will
571 * come back here when he is unchoked. Don't call the user
572 * callback to enforce ordering of spilling, he'll get called
573 * when we come back here and there's nothing more to spill.
579 wsi->extension_data_pending = 0;
584 pollfd->events &= ~POLLOUT;
586 /* external POLL support via protocol 0 */
587 context->protocols[0].callback(context, wsi,
588 LWS_CALLBACK_CLEAR_MODE_POLL_FD,
589 (void *)(long)wsi->sock, NULL, POLLOUT);
591 if (wsi->mode == LWS_CONNMODE_WS_CLIENT)
592 n = LWS_CALLBACK_CLIENT_WRITEABLE;
594 n = LWS_CALLBACK_SERVER_WRITEABLE;
596 wsi->protocol->callback(context, wsi, n, wsi->user_space, NULL, 0);
604 * libwebsocket_service_fd() - Service polled socket with something waiting
605 * @context: Websocket context
606 * @pollfd: The pollfd entry describing the socket fd and which events
609 * This function closes any active connections and then frees the
610 * context. After calling this, any further use of the context is
615 libwebsocket_service_fd(struct libwebsocket_context *context,
616 struct pollfd *pollfd)
618 unsigned char buf[LWS_SEND_BUFFER_PRE_PADDING + 1 + MAX_BROADCAST_PAYLOAD +
619 LWS_SEND_BUFFER_POST_PADDING];
620 struct libwebsocket *wsi;
621 struct libwebsocket *new_wsi;
627 struct sockaddr_in cli_addr;
629 static const char magic_websocket_guid[] =
630 "258EAFA5-E914-47DA-95CA-C5AB0DC85B11";
631 static const char magic_websocket_04_masking_guid[] =
632 "61AC5F19-FBBA-4540-B96F-6561F1AB40A8";
641 struct lws_tokens eff_buf;
643 struct libwebsocket_extension *ext;
645 #ifdef LWS_OPENSSL_SUPPORT
646 char ssl_err_buf[512];
649 * you can call us with pollfd = NULL to just allow the once-per-second
650 * global timeout checks; if less than a second since the last check
651 * it returns immediately then.
654 gettimeofday(&tv, NULL);
656 if (context->last_timeout_check_s != tv.tv_sec) {
657 context->last_timeout_check_s = tv.tv_sec;
659 /* global timeout check once per second */
661 for (n = 0; n < context->fds_count; n++) {
662 wsi = wsi_from_fd(context, context->fds[n].fd);
663 if (!wsi->pending_timeout)
667 * if we went beyond the allowed time, kill the
671 if (tv.tv_sec > wsi->pending_timeout_limit) {
672 fprintf(stderr, "TIMEDOUT WAITING\n");
673 libwebsocket_close_and_free_session(context,
674 wsi, LWS_CLOSE_STATUS_NOSTATUS);
679 /* just here for timeout management? */
684 /* no, here to service a socket descriptor */
686 wsi = wsi_from_fd(context, pollfd->fd);
692 case LWS_CONNMODE_SERVER_LISTENER:
694 /* pollin means a client has connected to us then */
696 if (!pollfd->revents & POLLIN)
699 /* listen socket got an unencrypted connection... */
701 clilen = sizeof(cli_addr);
702 accept_fd = accept(pollfd->fd, (struct sockaddr *)&cli_addr,
705 fprintf(stderr, "ERROR on accept");
709 if (context->fds_count >= MAX_CLIENTS) {
710 fprintf(stderr, "too busy to accept new client\n");
712 closesocket(accept_fd);
720 * look at who we connected to and give user code a chance
721 * to reject based on client IP. There's no protocol selected
722 * yet so we issue this to protocols[0]
725 if ((context->protocols[0].callback)(context, wsi,
726 LWS_CALLBACK_FILTER_NETWORK_CONNECTION,
727 (void*)(long)accept_fd, NULL, 0)) {
728 fprintf(stderr, "Callback denied network connection\n");
730 closesocket(accept_fd);
737 /* accepting connection to main listener */
739 new_wsi = malloc(sizeof(struct libwebsocket));
740 if (new_wsi == NULL) {
741 fprintf(stderr, "Out of memory for new connection\n");
745 memset(new_wsi, 0, sizeof (struct libwebsocket));
746 new_wsi->sock = accept_fd;
747 new_wsi->count_active_extensions = 0;
748 new_wsi->pending_timeout = NO_PENDING_TIMEOUT;
750 #ifdef LWS_OPENSSL_SUPPORT
753 if (context->use_ssl) {
755 new_wsi->ssl = SSL_new(context->ssl_ctx);
756 if (new_wsi->ssl == NULL) {
757 fprintf(stderr, "SSL_new failed: %s\n",
758 ERR_error_string(SSL_get_error(
759 new_wsi->ssl, 0), NULL));
760 libwebsockets_decode_ssl_error();
765 SSL_set_fd(new_wsi->ssl, accept_fd);
767 n = SSL_accept(new_wsi->ssl);
770 * browsers seem to probe with various
771 * ssl params which fail then retry
774 debug("SSL_accept failed skt %u: %s\n",
776 ERR_error_string(SSL_get_error(
777 new_wsi->ssl, n), NULL));
784 debug("accepted new SSL conn "
785 "port %u on fd=%d SSL ver %s\n",
786 ntohs(cli_addr.sin_port), accept_fd,
787 SSL_get_version(new_wsi->ssl));
791 debug("accepted new conn port %u on fd=%d\n",
792 ntohs(cli_addr.sin_port), accept_fd);
794 /* intialize the instance struct */
796 new_wsi->state = WSI_STATE_HTTP;
797 new_wsi->name_buffer_pos = 0;
798 new_wsi->mode = LWS_CONNMODE_WS_SERVING;
800 for (n = 0; n < WSI_TOKEN_COUNT; n++) {
801 new_wsi->utf8_token[n].token = NULL;
802 new_wsi->utf8_token[n].token_len = 0;
806 * these can only be set once the protocol is known
807 * we set an unestablished connection's protocol pointer
808 * to the start of the supported list, so it can look
809 * for matching ones during the handshake
811 new_wsi->protocol = context->protocols;
812 new_wsi->user_space = NULL;
815 * Default protocol is 76 / 00
816 * After 76, there's a header specified to inform which
817 * draft the client wants, when that's seen we modify
818 * the individual connection's spec revision accordingly
820 new_wsi->ietf_spec_revision = 0;
822 insert_wsi(context, new_wsi);
825 * make sure NO events are seen yet on this new socket
826 * (otherwise we inherit old fds[client].revents from
827 * previous socket there and die mysteriously! )
829 context->fds[context->fds_count].revents = 0;
831 context->fds[context->fds_count].events = POLLIN;
832 context->fds[context->fds_count++].fd = accept_fd;
834 /* external POLL support via protocol 0 */
835 context->protocols[0].callback(context, new_wsi,
836 LWS_CALLBACK_ADD_POLL_FD,
837 (void *)(long)accept_fd, NULL, POLLIN);
841 case LWS_CONNMODE_BROADCAST_PROXY_LISTENER:
843 /* as we are listening, POLLIN means accept() is needed */
845 if (!pollfd->revents & POLLIN)
848 /* listen socket got an unencrypted connection... */
850 clilen = sizeof(cli_addr);
851 accept_fd = accept(pollfd->fd, (struct sockaddr *)&cli_addr,
854 fprintf(stderr, "ERROR on accept");
858 if (context->fds_count >= MAX_CLIENTS) {
859 fprintf(stderr, "too busy to accept new broadcast "
862 closesocket(accept_fd);
869 /* create a dummy wsi for the connection and add it */
871 new_wsi = malloc(sizeof(struct libwebsocket));
872 memset(new_wsi, 0, sizeof (struct libwebsocket));
873 new_wsi->sock = accept_fd;
874 new_wsi->mode = LWS_CONNMODE_BROADCAST_PROXY;
875 new_wsi->state = WSI_STATE_ESTABLISHED;
876 new_wsi->count_active_extensions = 0;
877 /* note which protocol we are proxying */
878 new_wsi->protocol_index_for_broadcast_proxy =
879 wsi->protocol_index_for_broadcast_proxy;
880 insert_wsi(context, new_wsi);
882 /* add connected socket to internal poll array */
884 context->fds[context->fds_count].revents = 0;
885 context->fds[context->fds_count].events = POLLIN;
886 context->fds[context->fds_count++].fd = accept_fd;
888 /* external POLL support via protocol 0 */
889 context->protocols[0].callback(context, new_wsi,
890 LWS_CALLBACK_ADD_POLL_FD,
891 (void *)(long)accept_fd, NULL, POLLIN);
895 case LWS_CONNMODE_BROADCAST_PROXY:
897 /* handle session socket closed */
899 if (pollfd->revents & (POLLERR | POLLHUP)) {
901 debug("Session Socket %p (fd=%d) dead\n",
902 (void *)wsi, pollfd->fd);
904 libwebsocket_close_and_free_session(context, wsi,
905 LWS_CLOSE_STATUS_NORMAL);
910 * either extension code with stuff to spill, or the user code,
911 * requested a callback when it was OK to write
914 if (pollfd->revents & POLLOUT)
915 if (lws_handle_POLLOUT_event(context, wsi, pollfd) < 0) {
916 libwebsocket_close_and_free_session(context, wsi,
917 LWS_CLOSE_STATUS_NORMAL);
921 /* any incoming data ready? */
923 if (!(pollfd->revents & POLLIN))
926 /* get the issued broadcast payload from the socket */
928 len = read(pollfd->fd, buf + LWS_SEND_BUFFER_PRE_PADDING,
929 MAX_BROADCAST_PAYLOAD);
931 fprintf(stderr, "Error reading broadcast payload\n");
935 /* broadcast it to all guys with this protocol index */
937 for (n = 0; n < FD_HASHTABLE_MODULUS; n++) {
939 for (m = 0; m < context->fd_hashtable[n].length; m++) {
941 new_wsi = context->fd_hashtable[n].wsi[m];
943 /* only to clients we are serving to */
945 if (new_wsi->mode != LWS_CONNMODE_WS_SERVING)
949 * never broadcast to non-established
953 if (new_wsi->state != WSI_STATE_ESTABLISHED)
957 * only broadcast to connections using
958 * the requested protocol
961 if (new_wsi->protocol->protocol_index !=
962 wsi->protocol_index_for_broadcast_proxy)
965 /* broadcast it to this connection */
967 new_wsi->protocol->callback(context, new_wsi,
968 LWS_CALLBACK_BROADCAST,
970 buf + LWS_SEND_BUFFER_PRE_PADDING, len);
975 case LWS_CONNMODE_WS_CLIENT_WAITING_PROXY_REPLY:
977 /* handle proxy hung up on us */
979 if (pollfd->revents & (POLLERR | POLLHUP)) {
981 fprintf(stderr, "Proxy connection %p (fd=%d) dead\n",
982 (void *)wsi, pollfd->fd);
984 libwebsocket_close_and_free_session(context, wsi,
985 LWS_CLOSE_STATUS_NOSTATUS);
989 n = recv(wsi->sock, pkt, sizeof pkt, 0);
991 libwebsocket_close_and_free_session(context, wsi,
992 LWS_CLOSE_STATUS_NOSTATUS);
993 fprintf(stderr, "ERROR reading from proxy socket\n");
998 if (strcmp(pkt, "HTTP/1.0 200 ") != 0) {
999 libwebsocket_close_and_free_session(context, wsi,
1000 LWS_CLOSE_STATUS_NOSTATUS);
1001 fprintf(stderr, "ERROR from proxy: %s\n", pkt);
1005 /* clear his proxy connection timeout */
1007 libwebsocket_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
1011 case LWS_CONNMODE_WS_CLIENT_ISSUE_HANDSHAKE:
1013 #ifdef LWS_OPENSSL_SUPPORT
1016 wsi->ssl = SSL_new(context->ssl_client_ctx);
1017 wsi->client_bio = BIO_new_socket(wsi->sock,
1019 SSL_set_bio(wsi->ssl, wsi->client_bio, wsi->client_bio);
1021 SSL_set_ex_data(wsi->ssl,
1022 openssl_websocket_private_data_index,
1025 if (SSL_connect(wsi->ssl) <= 0) {
1026 fprintf(stderr, "SSL connect error %s\n",
1027 ERR_error_string(ERR_get_error(),
1029 libwebsocket_close_and_free_session(context, wsi,
1030 LWS_CLOSE_STATUS_NOSTATUS);
1034 n = SSL_get_verify_result(wsi->ssl);
1035 if ((n != X509_V_OK) && (
1036 n != X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT ||
1037 wsi->use_ssl != 2)) {
1039 fprintf(stderr, "server's cert didn't "
1040 "look good %d\n", n);
1041 libwebsocket_close_and_free_session(context,
1042 wsi, LWS_CLOSE_STATUS_NOSTATUS);
1050 #ifdef LWS_OPENSSL_SUPPORT
1055 * create the random key
1058 n = libwebsockets_get_random(context, hash, 16);
1060 fprintf(stderr, "Unable to read from random dev %s\n",
1061 SYSTEM_RANDOM_FILEPATH);
1065 free(wsi->c_origin);
1066 if (wsi->c_protocol)
1067 free(wsi->c_protocol);
1068 libwebsocket_close_and_free_session(context, wsi,
1069 LWS_CLOSE_STATUS_NOSTATUS);
1073 lws_b64_encode_string(hash, 16, wsi->key_b64,
1074 sizeof wsi->key_b64);
1077 * 00 example client handshake
1079 * GET /socket.io/websocket HTTP/1.1
1080 * Upgrade: WebSocket
1081 * Connection: Upgrade
1082 * Host: 127.0.0.1:9999
1083 * Origin: http://127.0.0.1
1084 * Sec-WebSocket-Key1: 1 0 2#0W 9 89 7 92 ^
1085 * Sec-WebSocket-Key2: 7 7Y 4328 B2v[8(z1
1086 * Cookie: socketio=websocket
1090 * 04 example client handshake
1092 * GET /chat HTTP/1.1
1093 * Host: server.example.com
1094 * Upgrade: websocket
1095 * Connection: Upgrade
1096 * Sec-WebSocket-Key: dGhlIHNhbXBsZSBub25jZQ==
1097 * Sec-WebSocket-Origin: http://example.com
1098 * Sec-WebSocket-Protocol: chat, superchat
1099 * Sec-WebSocket-Version: 4
1102 p += sprintf(p, "GET %s HTTP/1.1\x0d\x0a", wsi->c_path);
1104 if (wsi->ietf_spec_revision == 0) {
1105 unsigned char spaces_1, spaces_2;
1106 unsigned int max_1, max_2;
1107 unsigned int num_1, num_2;
1108 unsigned long product_1, product_2;
1115 libwebsockets_get_random(context, &spaces_1,
1117 libwebsockets_get_random(context, &spaces_2,
1120 spaces_1 = (spaces_1 % 12) + 1;
1121 spaces_2 = (spaces_2 % 12) + 1;
1123 max_1 = 4294967295 / spaces_1;
1124 max_2 = 4294967295 / spaces_2;
1126 libwebsockets_get_random(context, &num_1, sizeof(int));
1127 libwebsockets_get_random(context, &num_2, sizeof(int));
1129 num_1 = (num_1 % max_1);
1130 num_2 = (num_2 % max_2);
1132 challenge[0] = num_1 >> 24;
1133 challenge[1] = num_1 >> 16;
1134 challenge[2] = num_1 >> 8;
1135 challenge[3] = num_1;
1136 challenge[4] = num_2 >> 24;
1137 challenge[5] = num_2 >> 16;
1138 challenge[6] = num_2 >> 8;
1139 challenge[7] = num_2;
1141 product_1 = num_1 * spaces_1;
1142 product_2 = num_2 * spaces_2;
1144 sprintf(key_1, "%lu", product_1);
1145 sprintf(key_2, "%lu", product_2);
1147 libwebsockets_get_random(context, &seed, sizeof(int));
1148 libwebsockets_get_random(context, &count, sizeof(int));
1150 libwebsockets_00_spam(key_1, (count % 12) + 1, seed);
1152 libwebsockets_get_random(context, &seed, sizeof(int));
1153 libwebsockets_get_random(context, &count, sizeof(int));
1155 libwebsockets_00_spam(key_2, (count % 12) + 1, seed);
1157 libwebsockets_get_random(context, &seed, sizeof(int));
1159 libwebsockets_00_spaceout(key_1, spaces_1, seed);
1160 libwebsockets_00_spaceout(key_2, spaces_2, seed >> 16);
1162 p += sprintf(p, "Upgrade: websocket\x0d\x0a"
1163 "Connection: Upgrade\x0d\x0aHost: %s\x0d\x0a",
1166 p += sprintf(p, "Origin: %s\x0d\x0a",
1169 if (wsi->c_protocol)
1170 p += sprintf(p, "Sec-WebSocket-Protocol: %s"
1171 "\x0d\x0a", wsi->c_protocol);
1173 p += sprintf(p, "Sec-WebSocket-Key1: %s\x0d\x0a",
1175 p += sprintf(p, "Sec-WebSocket-Key2: %s\x0d\x0a",
1178 /* give userland a chance to append, eg, cookies */
1180 context->protocols[0].callback(context, wsi,
1181 LWS_CALLBACK_CLIENT_APPEND_HANDSHAKE_HEADER,
1182 NULL, &p, (pkt + sizeof(pkt)) - p - 12);
1184 p += sprintf(p, "\x0d\x0a");
1186 read(context->fd_random, p, 8);
1187 memcpy(&challenge[8], p, 8);
1190 /* precompute what we want to see from the server */
1192 MD5((unsigned char *)challenge, 16,
1193 (unsigned char *)wsi->initial_handshake_hash_base64);
1198 p += sprintf(p, "Host: %s\x0d\x0a", wsi->c_host);
1199 p += sprintf(p, "Upgrade: websocket\x0d\x0a");
1200 p += sprintf(p, "Connection: Upgrade\x0d\x0a"
1201 "Sec-WebSocket-Key: ");
1202 strcpy(p, wsi->key_b64);
1203 p += strlen(wsi->key_b64);
1204 p += sprintf(p, "\x0d\x0a");
1206 p += sprintf(p, "Sec-WebSocket-Origin: %s\x0d\x0a",
1208 if (wsi->c_protocol)
1209 p += sprintf(p, "Sec-WebSocket-Protocol: %s\x0d\x0a",
1212 /* tell the server what extensions we could support */
1214 p += sprintf(p, "Sec-WebSocket-Extensions: ");
1216 ext =context->extensions;
1217 while (ext && ext->callback) {
1220 n = context->protocols[0].callback(context, wsi,
1221 LWS_CALLBACK_CLIENT_CONFIRM_EXTENSION_SUPPORTED,
1222 wsi->user_space, (char *)ext->name, 0);
1225 * zero return from callback means
1226 * go ahead and allow the extension,
1227 * it's what we get if the callback is
1240 p += sprintf(p, ext->name);
1246 p += sprintf(p, "\x0d\x0a");
1248 if (wsi->ietf_spec_revision)
1249 p += sprintf(p, "Sec-WebSocket-Version: %d\x0d\x0a",
1250 wsi->ietf_spec_revision);
1252 /* give userland a chance to append, eg, cookies */
1254 context->protocols[0].callback(context, wsi,
1255 LWS_CALLBACK_CLIENT_APPEND_HANDSHAKE_HEADER,
1256 NULL, &p, (pkt + sizeof(pkt)) - p - 12);
1258 p += sprintf(p, "\x0d\x0a");
1260 /* prepare the expected server accept response */
1262 strcpy((char *)buf, wsi->key_b64);
1263 strcpy((char *)&buf[strlen((char *)buf)], magic_websocket_guid);
1265 SHA1(buf, strlen((char *)buf), (unsigned char *)hash);
1267 lws_b64_encode_string(hash, 20,
1268 wsi->initial_handshake_hash_base64,
1269 sizeof wsi->initial_handshake_hash_base64);
1273 /* done with these now */
1278 free(wsi->c_origin);
1280 /* send our request to the server */
1282 #ifdef LWS_OPENSSL_SUPPORT
1284 n = SSL_write(wsi->ssl, pkt, p - pkt);
1287 n = send(wsi->sock, pkt, p - pkt, 0);
1290 fprintf(stderr, "ERROR writing to client socket\n");
1291 libwebsocket_close_and_free_session(context, wsi,
1292 LWS_CLOSE_STATUS_NOSTATUS);
1296 wsi->parser_state = WSI_TOKEN_NAME_PART;
1297 wsi->mode = LWS_CONNMODE_WS_CLIENT_WAITING_SERVER_REPLY;
1298 libwebsocket_set_timeout(wsi,
1299 PENDING_TIMEOUT_AWAITING_SERVER_RESPONSE, 5);
1303 case LWS_CONNMODE_WS_CLIENT_WAITING_SERVER_REPLY:
1305 /* handle server hung up on us */
1307 if (pollfd->revents & (POLLERR | POLLHUP)) {
1309 fprintf(stderr, "Server connection %p (fd=%d) dead\n",
1310 (void *)wsi, pollfd->fd);
1316 /* interpret the server response */
1319 * HTTP/1.1 101 Switching Protocols
1320 * Upgrade: websocket
1321 * Connection: Upgrade
1322 * Sec-WebSocket-Accept: me89jWimTRKTWwrS3aRrL53YZSo=
1323 * Sec-WebSocket-Nonce: AQIDBAUGBwgJCgsMDQ4PEC==
1324 * Sec-WebSocket-Protocol: chat
1327 #ifdef LWS_OPENSSL_SUPPORT
1329 len = SSL_read(wsi->ssl, pkt, sizeof pkt);
1332 len = recv(wsi->sock, pkt, sizeof pkt, 0);
1336 "libwebsocket_client_handshake read error\n");
1341 for (n = 0; n < len; n++)
1342 libwebsocket_parse(wsi, *p++);
1344 if (wsi->parser_state != WSI_PARSING_COMPLETE) {
1345 fprintf(stderr, "libwebsocket_client_handshake "
1346 "server response failed parsing\n");
1353 * HTTP/1.1 101 WebSocket Protocol Handshake
1354 * Upgrade: WebSocket
1355 * Connection: Upgrade
1356 * Sec-WebSocket-Origin: http://127.0.0.1
1357 * Sec-WebSocket-Location: ws://127.0.0.1:9999/socket.io/websocket
1362 if (wsi->ietf_spec_revision == 0) {
1363 if (!wsi->utf8_token[WSI_TOKEN_HTTP].token_len ||
1364 !wsi->utf8_token[WSI_TOKEN_UPGRADE].token_len ||
1365 !wsi->utf8_token[WSI_TOKEN_CHALLENGE].token_len ||
1366 !wsi->utf8_token[WSI_TOKEN_CONNECTION].token_len ||
1367 (!wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len &&
1368 wsi->c_protocol != NULL)) {
1369 fprintf(stderr, "libwebsocket_client_handshake "
1370 "missing required header(s)\n");
1372 fprintf(stderr, "%s", pkt);
1376 strtolower(wsi->utf8_token[WSI_TOKEN_HTTP].token);
1377 if (strcmp(wsi->utf8_token[WSI_TOKEN_HTTP].token,
1378 "101 websocket protocol handshake")) {
1379 fprintf(stderr, "libwebsocket_client_handshake "
1380 "server sent bad HTTP response '%s'\n",
1381 wsi->utf8_token[WSI_TOKEN_HTTP].token);
1385 if (wsi->utf8_token[WSI_TOKEN_CHALLENGE].token_len <
1387 fprintf(stderr, "libwebsocket_client_handshake "
1388 "challenge reply too short %d\n",
1390 WSI_TOKEN_CHALLENGE].token_len);
1392 fprintf(stderr, "%s", pkt);
1397 goto select_protocol;
1401 * well, what the server sent looked reasonable for syntax.
1402 * Now let's confirm it sent all the necessary headers
1405 if (!wsi->utf8_token[WSI_TOKEN_HTTP].token_len ||
1406 !wsi->utf8_token[WSI_TOKEN_UPGRADE].token_len ||
1407 !wsi->utf8_token[WSI_TOKEN_CONNECTION].token_len ||
1408 !wsi->utf8_token[WSI_TOKEN_ACCEPT].token_len ||
1409 (!wsi->utf8_token[WSI_TOKEN_NONCE].token_len &&
1410 wsi->ietf_spec_revision == 4) ||
1411 (!wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len &&
1412 wsi->c_protocol != NULL)) {
1413 fprintf(stderr, "libwebsocket_client_handshake "
1414 "missing required header(s)\n");
1416 fprintf(stderr, "%s", pkt);
1421 * Everything seems to be there, now take a closer look at what
1425 strtolower(wsi->utf8_token[WSI_TOKEN_HTTP].token);
1426 if (strcmp(wsi->utf8_token[WSI_TOKEN_HTTP].token,
1427 "101 switching protocols")) {
1428 fprintf(stderr, "libwebsocket_client_handshake "
1429 "server sent bad HTTP response '%s'\n",
1430 wsi->utf8_token[WSI_TOKEN_HTTP].token);
1434 strtolower(wsi->utf8_token[WSI_TOKEN_UPGRADE].token);
1435 if (strcmp(wsi->utf8_token[WSI_TOKEN_UPGRADE].token,
1437 fprintf(stderr, "libwebsocket_client_handshake server "
1438 "sent bad Upgrade header '%s'\n",
1439 wsi->utf8_token[WSI_TOKEN_UPGRADE].token);
1443 strtolower(wsi->utf8_token[WSI_TOKEN_CONNECTION].token);
1444 if (strcmp(wsi->utf8_token[WSI_TOKEN_CONNECTION].token,
1446 fprintf(stderr, "libwebsocket_client_handshake server "
1447 "sent bad Connection hdr '%s'\n",
1448 wsi->utf8_token[WSI_TOKEN_CONNECTION].token);
1453 pc = wsi->c_protocol;
1456 * confirm the protocol the server wants to talk was in the list
1457 * of protocols we offered
1460 if (!wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len) {
1463 * no protocol name to work from,
1464 * default to first protocol
1466 wsi->protocol = &context->protocols[0];
1468 free(wsi->c_protocol);
1473 while (*pc && !okay) {
1475 wsi->utf8_token[WSI_TOKEN_PROTOCOL].token,
1476 wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len)) &&
1477 (pc[wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len] == ',' ||
1478 pc[wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len] == '\0')) {
1482 while (*pc && *pc != ',')
1484 while (*pc && *pc != ' ')
1488 /* done with him now */
1490 if (wsi->c_protocol)
1491 free(wsi->c_protocol);
1495 fprintf(stderr, "libwebsocket_client_handshake server "
1496 "sent bad protocol '%s'\n",
1497 wsi->utf8_token[WSI_TOKEN_PROTOCOL].token);
1502 * identify the selected protocol struct and set it
1505 wsi->protocol = NULL;
1506 while (context->protocols[n].callback) {
1507 if (strcmp(wsi->utf8_token[WSI_TOKEN_PROTOCOL].token,
1508 context->protocols[n].name) == 0)
1509 wsi->protocol = &context->protocols[n];
1513 if (wsi->protocol == NULL) {
1514 fprintf(stderr, "libwebsocket_client_handshake server "
1515 "requested protocol '%s', which we "
1516 "said we supported but we don't!\n",
1517 wsi->utf8_token[WSI_TOKEN_PROTOCOL].token);
1522 /* instantiate the accepted extensions */
1524 if (!wsi->utf8_token[WSI_TOKEN_EXTENSIONS].token_len)
1528 * break down the list of server accepted extensions
1529 * and go through matching them or identifying bogons
1532 c = wsi->utf8_token[WSI_TOKEN_EXTENSIONS].token;
1536 if (*c && *c != ',') {
1538 if (n < sizeof(ext_name) - 1)
1546 /* check we actually support it */
1549 ext = wsi->protocol->owning_server->extensions;
1550 while (ext && ext->callback) {
1552 if (strcmp(ext_name, ext->name)) {
1559 /* instantiate the extension on this conn */
1561 wsi->active_extensions_user[
1562 wsi->count_active_extensions] =
1563 malloc(ext->per_session_data_size);
1564 wsi->active_extensions[
1565 wsi->count_active_extensions] = ext;
1567 /* allow him to construct his context */
1569 ext->callback(wsi->protocol->owning_server,
1570 wsi, LWS_EXT_CALLBACK_CLIENT_CONSTRUCT,
1571 wsi->active_extensions_user[
1572 wsi->count_active_extensions], NULL, 0);
1574 wsi->count_active_extensions++;
1580 fprintf(stderr, "Server said we should use"
1581 "an unknown extension '%s'!\n", ext_name);
1591 if (wsi->ietf_spec_revision == 0) {
1593 if (memcmp(wsi->initial_handshake_hash_base64,
1594 wsi->utf8_token[WSI_TOKEN_CHALLENGE].token, 16)) {
1595 fprintf(stderr, "libwebsocket_client_handshake "
1596 "failed 00 challenge compare\n");
1598 fprintf(stderr, "%s", pkt);
1606 * Confirm his accept token is the one we precomputed
1609 if (strcmp(wsi->utf8_token[WSI_TOKEN_ACCEPT].token,
1610 wsi->initial_handshake_hash_base64)) {
1611 fprintf(stderr, "libwebsocket_client_handshake server "
1612 "sent bad ACCEPT '%s' vs computed '%s'\n",
1613 wsi->utf8_token[WSI_TOKEN_ACCEPT].token,
1614 wsi->initial_handshake_hash_base64);
1618 if (wsi->ietf_spec_revision == 4) {
1620 * Calculate the 04 masking key to use when
1621 * sending data to server
1624 strcpy((char *)buf, wsi->key_b64);
1625 p = (char *)buf + strlen(wsi->key_b64);
1626 strcpy(p, wsi->utf8_token[WSI_TOKEN_NONCE].token);
1627 p += wsi->utf8_token[WSI_TOKEN_NONCE].token_len;
1628 strcpy(p, magic_websocket_04_masking_guid);
1629 SHA1(buf, strlen((char *)buf), wsi->masking_key_04);
1633 /* allocate the per-connection user memory (if any) */
1635 if (wsi->protocol->per_session_data_size) {
1636 wsi->user_space = malloc(
1637 wsi->protocol->per_session_data_size);
1638 if (wsi->user_space == NULL) {
1639 fprintf(stderr, "Out of memory for "
1640 "conn user space\n");
1644 wsi->user_space = NULL;
1646 /* clear his proxy connection timeout */
1648 libwebsocket_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
1650 /* mark him as being alive */
1652 wsi->state = WSI_STATE_ESTABLISHED;
1653 wsi->mode = LWS_CONNMODE_WS_CLIENT;
1655 fprintf(stderr, "handshake OK for protocol %s\n",
1656 wsi->protocol->name);
1658 /* call him back to inform him he is up */
1660 wsi->protocol->callback(context, wsi,
1661 LWS_CALLBACK_CLIENT_ESTABLISHED,
1668 if (wsi->c_protocol)
1669 free(wsi->c_protocol);
1672 libwebsocket_close_and_free_session(context, wsi,
1673 LWS_CLOSE_STATUS_NOSTATUS);
1677 case LWS_CONNMODE_WS_SERVING:
1678 case LWS_CONNMODE_WS_CLIENT:
1680 /* handle session socket closed */
1682 if (pollfd->revents & (POLLERR | POLLHUP)) {
1684 fprintf(stderr, "Session Socket %p (fd=%d) dead\n",
1685 (void *)wsi, pollfd->fd);
1687 libwebsocket_close_and_free_session(context, wsi,
1688 LWS_CLOSE_STATUS_NOSTATUS);
1692 /* the guy requested a callback when it was OK to write */
1694 if ((pollfd->revents & POLLOUT) &&
1695 wsi->state == WSI_STATE_ESTABLISHED)
1696 if (lws_handle_POLLOUT_event(context, wsi,
1698 libwebsocket_close_and_free_session(
1699 context, wsi, LWS_CLOSE_STATUS_NORMAL);
1704 /* any incoming data ready? */
1706 if (!(pollfd->revents & POLLIN))
1709 #ifdef LWS_OPENSSL_SUPPORT
1711 eff_buf.token_len = SSL_read(wsi->ssl, buf, sizeof buf);
1715 recv(pollfd->fd, buf, sizeof buf, 0);
1717 if (eff_buf.token_len < 0) {
1718 fprintf(stderr, "Socket read returned %d\n",
1722 if (!eff_buf.token_len) {
1723 libwebsocket_close_and_free_session(context, wsi,
1724 LWS_CLOSE_STATUS_NOSTATUS);
1729 * give any active extensions a chance to munge the buffer
1730 * before parse. We pass in a pointer to an lws_tokens struct
1731 * prepared with the default buffer and content length that's in
1732 * there. Rather than rewrite the default buffer, extensions
1733 * that expect to grow the buffer can adapt .token to
1734 * point to their own per-connection buffer in the extension
1735 * user allocation. By default with no extensions or no
1736 * extension callback handling, just the normal input buffer is
1737 * used then so it is efficient.
1740 eff_buf.token = (char *)buf;
1747 for (n = 0; n < wsi->count_active_extensions; n++) {
1748 m = wsi->active_extensions[n]->callback(context, wsi,
1749 LWS_EXT_CALLBACK_PACKET_RX_PREPARSE,
1750 wsi->active_extensions_user[n], &eff_buf, 0);
1752 fprintf(stderr, "Extension reports fatal error\n");
1753 libwebsocket_close_and_free_session(context, wsi,
1754 LWS_CLOSE_STATUS_NOSTATUS);
1761 /* service incoming data */
1763 if (eff_buf.token_len) {
1764 n = libwebsocket_read(context, wsi,
1765 (unsigned char *)eff_buf.token, eff_buf.token_len);
1771 eff_buf.token = NULL;
1772 eff_buf.token_len = 0;
1782 * libwebsocket_context_destroy() - Destroy the websocket context
1783 * @context: Websocket context
1785 * This function closes any active connections and then frees the
1786 * context. After calling this, any further use of the context is
1790 libwebsocket_context_destroy(struct libwebsocket_context *context)
1794 struct libwebsocket *wsi;
1796 for (n = 0; n < FD_HASHTABLE_MODULUS; n++)
1797 for (m = 0; m < context->fd_hashtable[n].length; m++) {
1798 wsi = context->fd_hashtable[n].wsi[m];
1799 libwebsocket_close_and_free_session(context, wsi,
1800 LWS_CLOSE_STATUS_GOINGAWAY);
1805 close(context->fd_random);
1808 #ifdef LWS_OPENSSL_SUPPORT
1809 if (context->ssl_ctx)
1810 SSL_CTX_free(context->ssl_ctx);
1811 if (context->ssl_client_ctx)
1812 SSL_CTX_free(context->ssl_client_ctx);
1823 * libwebsocket_service() - Service any pending websocket activity
1824 * @context: Websocket context
1825 * @timeout_ms: Timeout for poll; 0 means return immediately if nothing needed
1826 * service otherwise block and service immediately, returning
1827 * after the timeout if nothing needed service.
1829 * This function deals with any pending websocket traffic, for three
1830 * kinds of event. It handles these events on both server and client
1831 * types of connection the same.
1833 * 1) Accept new connections to our context's server
1835 * 2) Perform pending broadcast writes initiated from other forked
1836 * processes (effectively serializing asynchronous broadcasts)
1838 * 3) Call the receive callback for incoming frame data received by
1839 * server or client connections.
1841 * You need to call this service function periodically to all the above
1842 * functions to happen; if your application is single-threaded you can
1843 * just call it in your main event loop.
1845 * Alternatively you can fork a new process that asynchronously handles
1846 * calling this service in a loop. In that case you are happy if this
1847 * call blocks your thread until it needs to take care of something and
1848 * would call it with a large nonzero timeout. Your loop then takes no
1849 * CPU while there is nothing happening.
1851 * If you are calling it in a single-threaded app, you don't want it to
1852 * wait around blocking other things in your loop from happening, so you
1853 * would call it with a timeout_ms of 0, so it returns immediately if
1854 * nothing is pending, or as soon as it services whatever was pending.
1859 libwebsocket_service(struct libwebsocket_context *context, int timeout_ms)
1863 /* stay dead once we are dead */
1865 if (context == NULL)
1868 /* wait for something to need service */
1870 n = poll(context->fds, context->fds_count, timeout_ms);
1871 if (n == 0) /* poll timeout */
1876 fprintf(stderr, "Listen Socket dead\n");
1881 /* handle accept on listening socket? */
1883 for (n = 0; n < context->fds_count; n++)
1884 if (context->fds[n].revents)
1885 libwebsocket_service_fd(context, &context->fds[n]);
1891 * libwebsocket_callback_on_writable() - Request a callback when this socket
1892 * becomes able to be written to without
1895 * @context: libwebsockets context
1896 * @wsi: Websocket connection instance to get callback for
1900 libwebsocket_callback_on_writable(struct libwebsocket_context *context,
1901 struct libwebsocket *wsi)
1905 for (n = 0; n < context->fds_count; n++)
1906 if (context->fds[n].fd == wsi->sock) {
1907 context->fds[n].events |= POLLOUT;
1908 n = context->fds_count;
1911 /* external POLL support via protocol 0 */
1912 context->protocols[0].callback(context, wsi,
1913 LWS_CALLBACK_SET_MODE_POLL_FD,
1914 (void *)(long)wsi->sock, NULL, POLLOUT);
1920 * libwebsocket_callback_on_writable_all_protocol() - Request a callback for
1921 * all connections using the given protocol when it
1922 * becomes possible to write to each socket without
1925 * @protocol: Protocol whose connections will get callbacks
1929 libwebsocket_callback_on_writable_all_protocol(
1930 const struct libwebsocket_protocols *protocol)
1932 struct libwebsocket_context *context = protocol->owning_server;
1935 struct libwebsocket *wsi;
1937 for (n = 0; n < FD_HASHTABLE_MODULUS; n++) {
1939 for (m = 0; m < context->fd_hashtable[n].length; m++) {
1941 wsi = context->fd_hashtable[n].wsi[m];
1943 if (wsi->protocol == protocol)
1944 libwebsocket_callback_on_writable(context, wsi);
1952 * libwebsocket_set_timeout() - marks the wsi as subject to a timeout
1954 * You will not need this unless you are doing something special
1956 * @wsi: Websocket connection instance
1957 * @reason: timeout reason
1958 * @secs: how many seconds
1962 libwebsocket_set_timeout(struct libwebsocket *wsi,
1963 enum pending_timeout reason, int secs)
1967 gettimeofday(&tv, NULL);
1969 wsi->pending_timeout_limit = tv.tv_sec + secs;
1970 wsi->pending_timeout = reason;
1975 * libwebsocket_get_socket_fd() - returns the socket file descriptor
1977 * You will not need this unless you are doing something special
1979 * @wsi: Websocket connection instance
1983 libwebsocket_get_socket_fd(struct libwebsocket *wsi)
1989 * libwebsocket_rx_flow_control() - Enable and disable socket servicing for
1990 * receieved packets.
1992 * If the output side of a server process becomes choked, this allows flow
1993 * control for the input side.
1995 * @wsi: Websocket connection instance to get callback for
1996 * @enable: 0 = disable read servicing for this connection, 1 = enable
2000 libwebsocket_rx_flow_control(struct libwebsocket *wsi, int enable)
2002 struct libwebsocket_context *context = wsi->protocol->owning_server;
2005 for (n = 0; n < context->fds_count; n++)
2006 if (context->fds[n].fd == wsi->sock) {
2008 context->fds[n].events |= POLLIN;
2010 context->fds[n].events &= ~POLLIN;
2016 /* external POLL support via protocol 0 */
2017 context->protocols[0].callback(context, wsi,
2018 LWS_CALLBACK_SET_MODE_POLL_FD,
2019 (void *)(long)wsi->sock, NULL, POLLIN);
2021 /* external POLL support via protocol 0 */
2022 context->protocols[0].callback(context, wsi,
2023 LWS_CALLBACK_CLEAR_MODE_POLL_FD,
2024 (void *)(long)wsi->sock, NULL, POLLIN);
2027 fprintf(stderr, "libwebsocket_callback_on_writable "
2028 "unable to find socket\n");
2033 * libwebsocket_canonical_hostname() - returns this host's hostname
2035 * This is typically used by client code to fill in the host parameter
2036 * when making a client connection. You can only call it after the context
2039 * @context: Websocket context
2044 libwebsocket_canonical_hostname(struct libwebsocket_context *context)
2046 return (const char *)context->canonical_hostname;
2050 static void sigpipe_handler(int x)
2054 #ifdef LWS_OPENSSL_SUPPORT
2056 OpenSSL_verify_callback(int preverify_ok, X509_STORE_CTX *x509_ctx)
2061 struct libwebsocket_context *context;
2063 ssl = X509_STORE_CTX_get_ex_data(x509_ctx,
2064 SSL_get_ex_data_X509_STORE_CTX_idx());
2067 * !!! nasty openssl requires the index to come as a library-scope
2070 context = SSL_get_ex_data(ssl, openssl_websocket_private_data_index);
2072 n = context->protocols[0].callback(NULL, NULL,
2073 LWS_CALLBACK_OPENSSL_PERFORM_CLIENT_CERT_VERIFICATION,
2074 x509_ctx, ssl, preverify_ok);
2076 /* convert return code from 0 = OK to 1 = OK */
2089 * libwebsocket_create_context() - Create the websocket handler
2090 * @port: Port to listen on... you can use 0 to suppress listening on
2091 * any port, that's what you want if you are not running a
2092 * websocket server at all but just using it as a client
2093 * @interf: NULL to bind the listen socket to all interfaces, or the
2094 * interface name, eg, "eth2"
2095 * @protocols: Array of structures listing supported protocols and a protocol-
2096 * specific callback for each one. The list is ended with an
2097 * entry that has a NULL callback pointer.
2098 * It's not const because we write the owning_server member
2099 * @extensions: NULL or array of libwebsocket_extension structs listing the
2100 * extensions this context supports
2101 * @ssl_cert_filepath: If libwebsockets was compiled to use ssl, and you want
2102 * to listen using SSL, set to the filepath to fetch the
2103 * server cert from, otherwise NULL for unencrypted
2104 * @ssl_private_key_filepath: filepath to private key if wanting SSL mode,
2106 * @gid: group id to change to after setting listen socket, or -1.
2107 * @uid: user id to change to after setting listen socket, or -1.
2108 * @options: 0, or LWS_SERVER_OPTION_DEFEAT_CLIENT_MASK
2110 * This function creates the listening socket and takes care
2111 * of all initialization in one step.
2113 * After initialization, it returns a struct libwebsocket_context * that
2114 * represents this server. After calling, user code needs to take care
2115 * of calling libwebsocket_service() with the context pointer to get the
2116 * server's sockets serviced. This can be done in the same process context
2117 * or a forked process, or another thread,
2119 * The protocol callback functions are called for a handful of events
2120 * including http requests coming in, websocket connections becoming
2121 * established, and data arriving; it's also called periodically to allow
2122 * async transmission.
2124 * HTTP requests are sent always to the FIRST protocol in @protocol, since
2125 * at that time websocket protocol has not been negotiated. Other
2126 * protocols after the first one never see any HTTP callack activity.
2128 * The server created is a simple http server by default; part of the
2129 * websocket standard is upgrading this http connection to a websocket one.
2131 * This allows the same server to provide files like scripts and favicon /
2132 * images or whatever over http and dynamic data over websockets all in
2133 * one place; they're all handled in the user callback.
2136 struct libwebsocket_context *
2137 libwebsocket_create_context(int port, const char *interf,
2138 struct libwebsocket_protocols *protocols,
2139 struct libwebsocket_extension *extensions,
2140 const char *ssl_cert_filepath,
2141 const char *ssl_private_key_filepath,
2142 int gid, int uid, unsigned int options)
2147 struct sockaddr_in serv_addr, cli_addr;
2149 struct libwebsocket_context *context = NULL;
2152 char hostname[1024];
2154 struct libwebsocket *wsi;
2156 #ifdef LWS_OPENSSL_SUPPORT
2158 char ssl_err_buf[512];
2163 WORD wVersionRequested;
2167 /* Use the MAKEWORD(lowbyte, highbyte) macro from Windef.h */
2168 wVersionRequested = MAKEWORD(2, 2);
2170 err = WSAStartup(wVersionRequested, &wsaData);
2172 /* Tell the user that we could not find a usable */
2174 fprintf(stderr, "WSAStartup failed with error: %d\n",
2182 context = malloc(sizeof(struct libwebsocket_context));
2184 fprintf(stderr, "No memory for websocket context\n");
2187 context->protocols = protocols;
2188 context->listen_port = port;
2189 context->http_proxy_port = 0;
2190 context->http_proxy_address[0] = '\0';
2191 context->options = options;
2192 context->fds_count = 0;
2193 context->extensions = extensions;
2196 context->fd_random = 0;
2198 context->fd_random = open(SYSTEM_RANDOM_FILEPATH, O_RDONLY);
2199 if (context->fd_random < 0) {
2200 fprintf(stderr, "Unable to open random device %s %d\n",
2201 SYSTEM_RANDOM_FILEPATH, context->fd_random);
2206 #ifdef LWS_OPENSSL_SUPPORT
2207 context->use_ssl = 0;
2208 context->ssl_ctx = NULL;
2209 context->ssl_client_ctx = NULL;
2210 openssl_websocket_private_data_index = 0;
2212 /* find canonical hostname */
2214 hostname[(sizeof hostname) - 1] = '\0';
2215 gethostname(hostname, (sizeof hostname) - 1);
2216 he = gethostbyname(hostname);
2218 strncpy(context->canonical_hostname, he->h_name,
2219 sizeof context->canonical_hostname - 1);
2220 context->canonical_hostname[
2221 sizeof context->canonical_hostname - 1] = '\0';
2223 strncpy(context->canonical_hostname, hostname,
2224 sizeof context->canonical_hostname - 1);
2226 /* split the proxy ads:port if given */
2228 p = getenv("http_proxy");
2230 strncpy(context->http_proxy_address, p,
2231 sizeof context->http_proxy_address - 1);
2232 context->http_proxy_address[
2233 sizeof context->http_proxy_address - 1] = '\0';
2235 p = strchr(context->http_proxy_address, ':');
2237 fprintf(stderr, "http_proxy needs to be ads:port\n");
2241 context->http_proxy_port = atoi(p + 1);
2243 fprintf(stderr, "Using proxy %s:%u\n",
2244 context->http_proxy_address,
2245 context->http_proxy_port);
2250 #ifdef LWS_OPENSSL_SUPPORT
2251 context->use_ssl = ssl_cert_filepath != NULL &&
2252 ssl_private_key_filepath != NULL;
2253 if (context->use_ssl)
2254 fprintf(stderr, " Compiled with SSL support, "
2257 fprintf(stderr, " Compiled with SSL support, "
2261 if (ssl_cert_filepath != NULL &&
2262 ssl_private_key_filepath != NULL) {
2263 fprintf(stderr, " Not compiled for OpenSSl support!\n");
2266 fprintf(stderr, " Compiled without SSL support, "
2267 "serving unencrypted\n");
2271 /* ignore SIGPIPE */
2274 signal(SIGPIPE, sigpipe_handler);
2278 #ifdef LWS_OPENSSL_SUPPORT
2280 /* basic openssl init */
2284 OpenSSL_add_all_algorithms();
2285 SSL_load_error_strings();
2287 openssl_websocket_private_data_index =
2288 SSL_get_ex_new_index(0, "libwebsockets", NULL, NULL, NULL);
2291 * Firefox insists on SSLv23 not SSLv3
2292 * Konq disables SSLv2 by default now, SSLv23 works
2295 method = (SSL_METHOD *)SSLv23_server_method();
2297 fprintf(stderr, "problem creating ssl method: %s\n",
2298 ERR_error_string(ERR_get_error(), ssl_err_buf));
2301 context->ssl_ctx = SSL_CTX_new(method); /* create context */
2302 if (!context->ssl_ctx) {
2303 fprintf(stderr, "problem creating ssl context: %s\n",
2304 ERR_error_string(ERR_get_error(), ssl_err_buf));
2308 /* client context */
2309 if (port == CONTEXT_PORT_NO_LISTEN)
2311 method = (SSL_METHOD *)SSLv23_client_method();
2313 fprintf(stderr, "problem creating ssl method: %s\n",
2314 ERR_error_string(ERR_get_error(), ssl_err_buf));
2317 /* create context */
2318 context->ssl_client_ctx = SSL_CTX_new(method);
2319 if (!context->ssl_client_ctx) {
2320 fprintf(stderr, "problem creating ssl context: %s\n",
2321 ERR_error_string(ERR_get_error(), ssl_err_buf));
2325 /* openssl init for cert verification (for client sockets) */
2327 if (!SSL_CTX_load_verify_locations(
2328 context->ssl_client_ctx, NULL,
2329 LWS_OPENSSL_CLIENT_CERTS))
2331 "Unable to load SSL Client certs from %s "
2332 "(set by --with-client-cert-dir= in configure) -- "
2333 " client ssl isn't going to work",
2334 LWS_OPENSSL_CLIENT_CERTS);
2337 * callback allowing user code to load extra verification certs
2338 * helping the client to verify server identity
2341 context->protocols[0].callback(context, NULL,
2342 LWS_CALLBACK_OPENSSL_LOAD_EXTRA_CLIENT_VERIFY_CERTS,
2343 context->ssl_client_ctx, NULL, 0);
2345 /* as a server, are we requiring clients to identify themselves? */
2347 if (options & LWS_SERVER_OPTION_REQUIRE_VALID_OPENSSL_CLIENT_CERT) {
2349 /* absolutely require the client cert */
2351 SSL_CTX_set_verify(context->ssl_ctx,
2352 SSL_VERIFY_PEER | SSL_VERIFY_FAIL_IF_NO_PEER_CERT,
2353 OpenSSL_verify_callback);
2356 * give user code a chance to load certs into the server
2357 * allowing it to verify incoming client certs
2360 context->protocols[0].callback(context, NULL,
2361 LWS_CALLBACK_OPENSSL_LOAD_EXTRA_SERVER_VERIFY_CERTS,
2362 context->ssl_ctx, NULL, 0);
2365 if (context->use_ssl) {
2367 /* openssl init for server sockets */
2369 /* set the local certificate from CertFile */
2370 n = SSL_CTX_use_certificate_file(context->ssl_ctx,
2371 ssl_cert_filepath, SSL_FILETYPE_PEM);
2373 fprintf(stderr, "problem getting cert '%s': %s\n",
2375 ERR_error_string(ERR_get_error(), ssl_err_buf));
2378 /* set the private key from KeyFile */
2379 if (SSL_CTX_use_PrivateKey_file(context->ssl_ctx,
2380 ssl_private_key_filepath, SSL_FILETYPE_PEM) != 1) {
2381 fprintf(stderr, "ssl problem getting key '%s': %s\n",
2382 ssl_private_key_filepath,
2383 ERR_error_string(ERR_get_error(), ssl_err_buf));
2386 /* verify private key */
2387 if (!SSL_CTX_check_private_key(context->ssl_ctx)) {
2388 fprintf(stderr, "Private SSL key doesn't match cert\n");
2392 /* SSL is happy and has a cert it's content with */
2398 if (lws_b64_selftest())
2401 /* fd hashtable init */
2403 for (n = 0; n < FD_HASHTABLE_MODULUS; n++)
2404 context->fd_hashtable[n].length = 0;
2406 /* set up our external listening socket we serve on */
2410 sockfd = socket(AF_INET, SOCK_STREAM, 0);
2412 fprintf(stderr, "ERROR opening socket");
2416 /* allow us to restart even if old sockets in TIME_WAIT */
2417 setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt));
2419 bzero((char *) &serv_addr, sizeof(serv_addr));
2420 serv_addr.sin_family = AF_INET;
2422 serv_addr.sin_addr.s_addr = INADDR_ANY;
2424 interface_to_sa(interf, &serv_addr,
2426 serv_addr.sin_port = htons(port);
2428 n = bind(sockfd, (struct sockaddr *) &serv_addr,
2431 fprintf(stderr, "ERROR on binding to port %d (%d %d)\n",
2436 wsi = malloc(sizeof(struct libwebsocket));
2437 memset(wsi, 0, sizeof (struct libwebsocket));
2439 wsi->count_active_extensions = 0;
2440 wsi->mode = LWS_CONNMODE_SERVER_LISTENER;
2441 insert_wsi(context, wsi);
2444 fprintf(stderr, " Listening on port %d\n", port);
2446 /* list in the internal poll array */
2448 context->fds[context->fds_count].fd = sockfd;
2449 context->fds[context->fds_count++].events = POLLIN;
2451 /* external POLL support via protocol 0 */
2452 context->protocols[0].callback(context, wsi,
2453 LWS_CALLBACK_ADD_POLL_FD,
2454 (void *)(long)sockfd, NULL, POLLIN);
2458 /* drop any root privs for this process */
2463 fprintf(stderr, "setgid: %s\n", strerror(errno));
2466 fprintf(stderr, "setuid: %s\n", strerror(errno));
2469 /* set up our internal broadcast trigger sockets per-protocol */
2471 for (context->count_protocols = 0;
2472 protocols[context->count_protocols].callback;
2473 context->count_protocols++) {
2474 protocols[context->count_protocols].owning_server = context;
2475 protocols[context->count_protocols].protocol_index =
2476 context->count_protocols;
2478 fd = socket(AF_INET, SOCK_STREAM, 0);
2480 fprintf(stderr, "ERROR opening socket");
2484 /* allow us to restart even if old sockets in TIME_WAIT */
2485 setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt));
2487 bzero((char *) &serv_addr, sizeof(serv_addr));
2488 serv_addr.sin_family = AF_INET;
2489 serv_addr.sin_addr.s_addr = inet_addr("127.0.0.1");
2490 serv_addr.sin_port = 0; /* pick the port for us */
2492 n = bind(fd, (struct sockaddr *) &serv_addr, sizeof(serv_addr));
2494 fprintf(stderr, "ERROR on binding to port %d (%d %d)\n",
2499 slen = sizeof cli_addr;
2500 n = getsockname(fd, (struct sockaddr *)&cli_addr, &slen);
2502 fprintf(stderr, "getsockname failed\n");
2505 protocols[context->count_protocols].broadcast_socket_port =
2506 ntohs(cli_addr.sin_port);
2509 debug(" Protocol %s broadcast socket %d\n",
2510 protocols[context->count_protocols].name,
2511 ntohs(cli_addr.sin_port));
2513 /* dummy wsi per broadcast proxy socket */
2515 wsi = malloc(sizeof(struct libwebsocket));
2516 memset(wsi, 0, sizeof (struct libwebsocket));
2518 wsi->mode = LWS_CONNMODE_BROADCAST_PROXY_LISTENER;
2519 wsi->count_active_extensions = 0;
2520 /* note which protocol we are proxying */
2521 wsi->protocol_index_for_broadcast_proxy =
2522 context->count_protocols;
2523 insert_wsi(context, wsi);
2525 /* list in internal poll array */
2527 context->fds[context->fds_count].fd = fd;
2528 context->fds[context->fds_count].events = POLLIN;
2529 context->fds[context->fds_count].revents = 0;
2530 context->fds_count++;
2532 /* external POLL support via protocol 0 */
2533 context->protocols[0].callback(context, wsi,
2534 LWS_CALLBACK_ADD_POLL_FD,
2535 (void *)(long)fd, NULL, POLLIN);
2545 * libwebsockets_fork_service_loop() - Optional helper function forks off
2546 * a process for the websocket server loop.
2547 * You don't have to use this but if not, you
2548 * have to make sure you are calling
2549 * libwebsocket_service periodically to service
2550 * the websocket traffic
2551 * @context: server context returned by creation function
2555 libwebsockets_fork_service_loop(struct libwebsocket_context *context)
2558 struct sockaddr_in cli_addr;
2568 /* main process context */
2571 * set up the proxy sockets to allow broadcast from
2572 * service process context
2575 for (p = 0; p < context->count_protocols; p++) {
2576 fd = socket(AF_INET, SOCK_STREAM, 0);
2578 fprintf(stderr, "Unable to create socket\n");
2581 cli_addr.sin_family = AF_INET;
2582 cli_addr.sin_port = htons(
2583 context->protocols[p].broadcast_socket_port);
2584 cli_addr.sin_addr.s_addr = inet_addr("127.0.0.1");
2585 n = connect(fd, (struct sockaddr *)&cli_addr,
2588 fprintf(stderr, "Unable to connect to "
2589 "broadcast socket %d, %s\n",
2590 n, strerror(errno));
2594 context->protocols[p].broadcast_socket_user_fd = fd;
2600 /* we want a SIGHUP when our parent goes down */
2601 prctl(PR_SET_PDEATHSIG, SIGHUP);
2603 /* in this forked process, sit and service websocket connections */
2606 if (libwebsocket_service(context, 1000))
2615 * libwebsockets_get_protocol() - Returns a protocol pointer from a websocket
2617 * @wsi: pointer to struct websocket you want to know the protocol of
2620 * This is useful to get the protocol to broadcast back to from inside
2624 const struct libwebsocket_protocols *
2625 libwebsockets_get_protocol(struct libwebsocket *wsi)
2627 return wsi->protocol;
2631 * libwebsockets_broadcast() - Sends a buffer to the callback for all active
2632 * connections of the given protocol.
2633 * @protocol: pointer to the protocol you will broadcast to all members of
2634 * @buf: buffer containing the data to be broadcase. NOTE: this has to be
2635 * allocated with LWS_SEND_BUFFER_PRE_PADDING valid bytes before
2636 * the pointer and LWS_SEND_BUFFER_POST_PADDING afterwards in the
2637 * case you are calling this function from callback context.
2638 * @len: length of payload data in buf, starting from buf.
2640 * This function allows bulk sending of a packet to every connection using
2641 * the given protocol. It does not send the data directly; instead it calls
2642 * the callback with a reason type of LWS_CALLBACK_BROADCAST. If the callback
2643 * wants to actually send the data for that connection, the callback itself
2644 * should call libwebsocket_write().
2646 * libwebsockets_broadcast() can be called from another fork context without
2647 * having to take any care about data visibility between the processes, it'll
2653 libwebsockets_broadcast(const struct libwebsocket_protocols *protocol,
2654 unsigned char *buf, size_t len)
2656 struct libwebsocket_context *context = protocol->owning_server;
2659 struct libwebsocket * wsi;
2661 if (!protocol->broadcast_socket_user_fd) {
2663 * We are either running unforked / flat, or we are being
2664 * called from poll thread context
2665 * eg, from a callback. In that case don't use sockets for
2666 * broadcast IPC (since we can't open a socket connection to
2667 * a socket listening on our own thread) but directly do the
2670 * Locking is not needed because we are by definition being
2671 * called in the poll thread context and are serialized.
2674 for (n = 0; n < FD_HASHTABLE_MODULUS; n++) {
2676 for (m = 0; m < context->fd_hashtable[n].length; m++) {
2678 wsi = context->fd_hashtable[n].wsi[m];
2680 if (wsi->mode != LWS_CONNMODE_WS_SERVING)
2684 * never broadcast to
2685 * non-established connections
2687 if (wsi->state != WSI_STATE_ESTABLISHED)
2690 /* only broadcast to guys using
2691 * requested protocol
2693 if (wsi->protocol != protocol)
2696 wsi->protocol->callback(context, wsi,
2697 LWS_CALLBACK_BROADCAST,
2707 * We're being called from a different process context than the server
2708 * loop. Instead of broadcasting directly, we send our
2709 * payload on a socket to do the IPC; the server process will serialize
2710 * the broadcast action in its main poll() loop.
2712 * There's one broadcast socket listening for each protocol supported
2713 * set up when the websocket server initializes
2716 n = send(protocol->broadcast_socket_user_fd, buf, len, MSG_NOSIGNAL);
2722 libwebsocket_is_final_fragment(struct libwebsocket *wsi)