2 * libwebsockets - small server side websockets and web server implementation
4 * Copyright (C) 2010-2013 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 #ifndef __LIBWEBSOCKET_H__
23 #define __LIBWEBSOCKET_H__
32 #ifndef WIN32_LEAN_AND_MEAN
33 #define WIN32_LEAN_AND_MEAN
38 #include "../win32port/win32helpers/websock-w32.h"
40 #include "../win32port/win32helpers/gettimeofday.h"
42 #define strcasecmp stricmp
43 #define getdtablesize() 30000
49 #define LWS_EXTERN extern __declspec(dllexport)
51 #define LWS_EXTERN extern __declspec(dllimport)
63 #define LWS_EXTERN extern
66 #define CONTEXT_PORT_NO_LISTEN 0
67 #define MAX_MUX_RECURSION 2
81 LLL_COUNT = 10 /* set to count of valid flags */
84 extern void _lws_log(int filter, const char *format, ...);
86 /* notice, warn and log are always compiled in */
87 #define lwsl_notice(...) _lws_log(LLL_NOTICE, __VA_ARGS__)
88 #define lwsl_warn(...) _lws_log(LLL_WARN, __VA_ARGS__)
89 #define lwsl_err(...) _lws_log(LLL_ERR, __VA_ARGS__)
91 * weaker logging can be deselected at configure time using --disable-debug
92 * that gets rid of the overhead of checking while keeping _warn and _err
97 #define lwsl_info(...) _lws_log(LLL_INFO, __VA_ARGS__)
98 #define lwsl_debug(...) _lws_log(LLL_DEBUG, __VA_ARGS__)
99 #define lwsl_parser(...) _lws_log(LLL_PARSER, __VA_ARGS__)
100 #define lwsl_header(...) _lws_log(LLL_HEADER, __VA_ARGS__)
101 #define lwsl_ext(...) _lws_log(LLL_EXT, __VA_ARGS__)
102 #define lwsl_client(...) _lws_log(LLL_CLIENT, __VA_ARGS__)
103 #define lwsl_latency(...) _lws_log(LLL_LATENCY, __VA_ARGS__)
104 extern void lwsl_hexdump(void *buf, size_t len);
108 #define lwsl_info(...)
109 #define lwsl_debug(...)
110 #define lwsl_parser(...)
111 #define lwsl_header(...)
112 #define lwsl_ext(...)
113 #define lwsl_client(...)
114 #define lwsl_latency(...)
115 #define lwsl_hexdump(a, b)
119 enum libwebsocket_context_options {
120 LWS_SERVER_OPTION_REQUIRE_VALID_OPENSSL_CLIENT_CERT = 2,
121 LWS_SERVER_OPTION_SKIP_SERVER_CANONICAL_NAME = 4,
124 enum libwebsocket_callback_reasons {
125 LWS_CALLBACK_ESTABLISHED,
126 LWS_CALLBACK_CLIENT_CONNECTION_ERROR,
127 LWS_CALLBACK_CLIENT_FILTER_PRE_ESTABLISH,
128 LWS_CALLBACK_CLIENT_ESTABLISHED,
130 LWS_CALLBACK_RECEIVE,
131 LWS_CALLBACK_CLIENT_RECEIVE,
132 LWS_CALLBACK_CLIENT_RECEIVE_PONG,
133 LWS_CALLBACK_CLIENT_WRITEABLE,
134 LWS_CALLBACK_SERVER_WRITEABLE,
136 LWS_CALLBACK_HTTP_FILE_COMPLETION,
137 LWS_CALLBACK_FILTER_NETWORK_CONNECTION,
138 LWS_CALLBACK_FILTER_PROTOCOL_CONNECTION,
139 LWS_CALLBACK_OPENSSL_LOAD_EXTRA_CLIENT_VERIFY_CERTS,
140 LWS_CALLBACK_OPENSSL_LOAD_EXTRA_SERVER_VERIFY_CERTS,
141 LWS_CALLBACK_OPENSSL_PERFORM_CLIENT_CERT_VERIFICATION,
142 LWS_CALLBACK_CLIENT_APPEND_HANDSHAKE_HEADER,
143 LWS_CALLBACK_CONFIRM_EXTENSION_OKAY,
144 LWS_CALLBACK_CLIENT_CONFIRM_EXTENSION_SUPPORTED,
145 LWS_CALLBACK_PROTOCOL_INIT,
146 LWS_CALLBACK_PROTOCOL_DESTROY,
147 /* external poll() management support */
148 LWS_CALLBACK_ADD_POLL_FD,
149 LWS_CALLBACK_DEL_POLL_FD,
150 LWS_CALLBACK_SET_MODE_POLL_FD,
151 LWS_CALLBACK_CLEAR_MODE_POLL_FD,
154 #ifndef LWS_NO_EXTENSIONS
155 enum libwebsocket_extension_callback_reasons {
156 LWS_EXT_CALLBACK_SERVER_CONTEXT_CONSTRUCT,
157 LWS_EXT_CALLBACK_CLIENT_CONTEXT_CONSTRUCT,
158 LWS_EXT_CALLBACK_SERVER_CONTEXT_DESTRUCT,
159 LWS_EXT_CALLBACK_CLIENT_CONTEXT_DESTRUCT,
160 LWS_EXT_CALLBACK_CONSTRUCT,
161 LWS_EXT_CALLBACK_CLIENT_CONSTRUCT,
162 LWS_EXT_CALLBACK_CHECK_OK_TO_REALLY_CLOSE,
163 LWS_EXT_CALLBACK_CHECK_OK_TO_PROPOSE_EXTENSION,
164 LWS_EXT_CALLBACK_DESTROY,
165 LWS_EXT_CALLBACK_DESTROY_ANY_WSI_CLOSING,
166 LWS_EXT_CALLBACK_ANY_WSI_ESTABLISHED,
167 LWS_EXT_CALLBACK_PACKET_RX_PREPARSE,
168 LWS_EXT_CALLBACK_PACKET_TX_PRESEND,
169 LWS_EXT_CALLBACK_PACKET_TX_DO_SEND,
170 LWS_EXT_CALLBACK_HANDSHAKE_REPLY_TX,
171 LWS_EXT_CALLBACK_FLUSH_PENDING_TX,
172 LWS_EXT_CALLBACK_EXTENDED_PAYLOAD_RX,
173 LWS_EXT_CALLBACK_CAN_PROXY_CLIENT_CONNECTION,
174 LWS_EXT_CALLBACK_1HZ,
175 LWS_EXT_CALLBACK_REQUEST_ON_WRITEABLE,
176 LWS_EXT_CALLBACK_IS_WRITEABLE,
177 LWS_EXT_CALLBACK_PAYLOAD_TX,
178 LWS_EXT_CALLBACK_PAYLOAD_RX,
182 enum libwebsocket_write_protocol {
185 LWS_WRITE_CONTINUATION,
188 /* special 04+ opcodes */
196 LWS_WRITE_NO_FIN = 0x40,
198 * client packet payload goes out on wire unmunged
199 * only useful for security tests since normal servers cannot
200 * decode the content if used
202 LWS_WRITE_CLIENT_IGNORE_XOR_MASK = 0x80
206 * you need these to look at headers that have been parsed if using the
207 * LWS_CALLBACK_FILTER_CONNECTION callback. If a header from the enum
208 * list below is absent, .token = NULL and token_len = 0. Otherwise .token
209 * points to .token_len chars containing that header content.
217 enum lws_token_indexes {
220 WSI_TOKEN_CONNECTION,
235 WSI_TOKEN_EXTENSIONS,
237 /* client receives these */
243 /* always last real token index*/
245 /* parser state additions */
248 WSI_TOKEN_SKIPPING_SAW_CR,
249 WSI_PARSING_COMPLETE,
250 WSI_INIT_TOKEN_MUXURL,
257 1000 indicates a normal closure, meaning that the purpose for
258 which the connection was established has been fulfilled.
262 1001 indicates that an endpoint is "going away", such as a server
263 going down or a browser having navigated away from a page.
267 1002 indicates that an endpoint is terminating the connection due
272 1003 indicates that an endpoint is terminating the connection
273 because it has received a type of data it cannot accept (e.g., an
274 endpoint that understands only text data MAY send this if it
275 receives a binary message).
279 Reserved. The specific meaning might be defined in the future.
283 1005 is a reserved value and MUST NOT be set as a status code in a
284 Close control frame by an endpoint. It is designated for use in
285 applications expecting a status code to indicate that no status
286 code was actually present.
290 1006 is a reserved value and MUST NOT be set as a status code in a
291 Close control frame by an endpoint. It is designated for use in
292 applications expecting a status code to indicate that the
293 connection was closed abnormally, e.g., without sending or
294 receiving a Close control frame.
298 1007 indicates that an endpoint is terminating the connection
299 because it has received data within a message that was not
300 consistent with the type of the message (e.g., non-UTF-8 [RFC3629]
301 data within a text message).
305 1008 indicates that an endpoint is terminating the connection
306 because it has received a message that violates its policy. This
307 is a generic status code that can be returned when there is no
308 other more suitable status code (e.g., 1003 or 1009) or if there
309 is a need to hide specific details about the policy.
313 1009 indicates that an endpoint is terminating the connection
314 because it has received a message that is too big for it to
319 1010 indicates that an endpoint (client) is terminating the
320 connection because it has expected the server to negotiate one or
321 more extension, but the server didn't return them in the response
322 message of the WebSocket handshake. The list of extensions that
323 are needed SHOULD appear in the /reason/ part of the Close frame.
324 Note that this status code is not used by the server, because it
325 can fail the WebSocket handshake instead.
329 1011 indicates that a server is terminating the connection because
330 it encountered an unexpected condition that prevented it from
331 fulfilling the request.
335 1015 is a reserved value and MUST NOT be set as a status code in a
336 Close control frame by an endpoint. It is designated for use in
337 applications expecting a status code to indicate that the
338 connection was closed due to a failure to perform a TLS handshake
339 (e.g., the server certificate can't be verified).
342 enum lws_close_status {
343 LWS_CLOSE_STATUS_NOSTATUS = 0,
344 LWS_CLOSE_STATUS_NORMAL = 1000,
345 LWS_CLOSE_STATUS_GOINGAWAY = 1001,
346 LWS_CLOSE_STATUS_PROTOCOL_ERR = 1002,
347 LWS_CLOSE_STATUS_UNACCEPTABLE_OPCODE = 1003,
348 LWS_CLOSE_STATUS_RESERVED = 1004,
349 LWS_CLOSE_STATUS_NO_STATUS = 1005,
350 LWS_CLOSE_STATUS_ABNORMAL_CLOSE = 1006,
351 LWS_CLOSE_STATUS_INVALID_PAYLOAD = 1007,
352 LWS_CLOSE_STATUS_POLICY_VIOLATION = 1008,
353 LWS_CLOSE_STATUS_MESSAGE_TOO_LARGE = 1009,
354 LWS_CLOSE_STATUS_EXTENSION_REQUIRED = 1010,
355 LWS_CLOSE_STATUS_UNEXPECTED_CONDITION = 1011,
356 LWS_CLOSE_STATUS_TLS_FAILURE = 1015,
360 struct libwebsocket_context;
361 /* needed even with extensions disabled for create context */
362 struct libwebsocket_extension;
365 * callback_function() - User server actions
366 * @context: Websockets context
367 * @wsi: Opaque websocket instance pointer
368 * @reason: The reason for the call
369 * @user: Pointer to per-session user data allocated by library
370 * @in: Pointer used for some callback reasons
371 * @len: Length set for some callback reasons
373 * This callback is the way the user controls what is served. All the
374 * protocol detail is hidden and handled by the library.
376 * For each connection / session there is user data allocated that is
377 * pointed to by "user". You set the size of this user data area when
378 * the library is initialized with libwebsocket_create_server.
380 * You get an opportunity to initialize user data when called back with
381 * LWS_CALLBACK_ESTABLISHED reason.
383 * LWS_CALLBACK_ESTABLISHED: after the server completes a handshake with
386 * LWS_CALLBACK_CLIENT_CONNECTION_ERROR: the request client connection has
387 * been unable to complete a handshake with the remote server
389 * LWS_CALLBACK_CLIENT_FILTER_PRE_ESTABLISH: this is the last chance for the
390 * client user code to examine the http headers
391 * and decide to reject the connection. If the
392 * content in the headers is interesting to the
393 * client (url, etc) it needs to copy it out at
394 * this point since it will be destroyed before
395 * the CLIENT_ESTABLISHED call
397 * LWS_CALLBACK_CLIENT_ESTABLISHED: after your client connection completed
398 * a handshake with the remote server
400 * LWS_CALLBACK_CLOSED: when the websocket session ends
402 * LWS_CALLBACK_RECEIVE: data has appeared for this server endpoint from a
403 * remote client, it can be found at *in and is
406 * LWS_CALLBACK_CLIENT_RECEIVE_PONG: if you elected to see PONG packets,
407 * they appear with this callback reason. PONG
408 * packets only exist in 04+ protocol
410 * LWS_CALLBACK_CLIENT_RECEIVE: data has appeared from the server for the
411 * client connection, it can be found at *in and
414 * LWS_CALLBACK_HTTP: an http request has come from a client that is not
415 * asking to upgrade the connection to a websocket
416 * one. This is a chance to serve http content,
417 * for example, to send a script to the client
418 * which will then open the websockets connection.
419 * @in points to the URI path requested and
420 * libwebsockets_serve_http_file() makes it very
421 * simple to send back a file to the client.
422 * Normally after sending the file you are done
423 * with the http connection, since the rest of the
424 * activity will come by websockets from the script
425 * that was delivered by http, so you will want to
426 * return 1; to close and free up the connection.
427 * That's important because it uses a slot in the
428 * total number of client connections allowed set
431 * LWS_CALLBACK_HTTP_FILE_COMPLETION: a file requested to be send down
432 * http link has completed.
434 * LWS_CALLBACK_CLIENT_WRITEABLE:
435 * LWS_CALLBACK_SERVER_WRITEABLE: If you call
436 * libwebsocket_callback_on_writable() on a connection, you will
437 * get one of these callbacks coming when the connection socket
438 * is able to accept another write packet without blocking.
439 * If it already was able to take another packet without blocking,
440 * you'll get this callback at the next call to the service loop
441 * function. Notice that CLIENTs get LWS_CALLBACK_CLIENT_WRITEABLE
442 * and servers get LWS_CALLBACK_SERVER_WRITEABLE.
444 * LWS_CALLBACK_FILTER_NETWORK_CONNECTION: called when a client connects to
445 * the server at network level; the connection is accepted but then
446 * passed to this callback to decide whether to hang up immediately
447 * or not, based on the client IP. @user contains the connection
448 * socket's descriptor. Return non-zero to terminate
449 * the connection before sending or receiving anything.
450 * Because this happens immediately after the network connection
451 * from the client, there's no websocket protocol selected yet so
452 * this callback is issued only to protocol 0.
454 * LWS_CALLBACK_FILTER_PROTOCOL_CONNECTION: called when the handshake has
455 * been received and parsed from the client, but the response is
456 * not sent yet. Return non-zero to disallow the connection.
457 * @user is a pointer to an array of struct lws_tokens, you can
458 * use the header enums lws_token_indexes from libwebsockets.h
459 * to check for and read the supported header presence and
460 * content before deciding to allow the handshake to proceed or
461 * to kill the connection.
463 * LWS_CALLBACK_OPENSSL_LOAD_EXTRA_CLIENT_VERIFY_CERTS: if configured for
464 * including OpenSSL support, this callback allows your user code
465 * to perform extra SSL_CTX_load_verify_locations() or similar
466 * calls to direct OpenSSL where to find certificates the client
467 * can use to confirm the remote server identity. @user is the
470 * LWS_CALLBACK_OPENSSL_LOAD_EXTRA_SERVER_VERIFY_CERTS: if configured for
471 * including OpenSSL support, this callback allows your user code
472 * to load extra certifcates into the server which allow it to
473 * verify the validity of certificates returned by clients. @user
474 * is the server's OpenSSL SSL_CTX*
476 * LWS_CALLBACK_OPENSSL_PERFORM_CLIENT_CERT_VERIFICATION: if the
477 * libwebsockets context was created with the option
478 * LWS_SERVER_OPTION_REQUIRE_VALID_OPENSSL_CLIENT_CERT, then this
479 * callback is generated during OpenSSL verification of the cert
480 * sent from the client. It is sent to protocol[0] callback as
481 * no protocol has been negotiated on the connection yet.
482 * Notice that the libwebsockets context and wsi are both NULL
483 * during this callback. See
484 * http://www.openssl.org/docs/ssl/SSL_CTX_set_verify.html
485 * to understand more detail about the OpenSSL callback that
486 * generates this libwebsockets callback and the meanings of the
487 * arguments passed. In this callback, @user is the x509_ctx,
488 * @in is the ssl pointer and @len is preverify_ok
489 * Notice that this callback maintains libwebsocket return
490 * conventions, return 0 to mean the cert is OK or 1 to fail it.
491 * This also means that if you don't handle this callback then
492 * the default callback action of returning 0 allows the client
495 * LWS_CALLBACK_CLIENT_APPEND_HANDSHAKE_HEADER: this callback happens
496 * when a client handshake is being compiled. @user is NULL,
497 * @in is a char **, it's pointing to a char * which holds the
498 * next location in the header buffer where you can add
499 * headers, and @len is the remaining space in the header buffer,
500 * which is typically some hundreds of bytes. So, to add a canned
501 * cookie, your handler code might look similar to:
503 * char **p = (char **)in;
508 * *p += sprintf(*p, "Cookie: a=b\x0d\x0a");
512 * Notice if you add anything, you just have to take care about
513 * the CRLF on the line you added. Obviously this callback is
514 * optional, if you don't handle it everything is fine.
516 * Notice the callback is coming to protocols[0] all the time,
517 * because there is no specific protocol handshook yet.
519 * LWS_CALLBACK_CONFIRM_EXTENSION_OKAY: When the server handshake code
520 * sees that it does support a requested extension, before
521 * accepting the extension by additing to the list sent back to
522 * the client it gives this callback just to check that it's okay
523 * to use that extension. It calls back to the requested protocol
524 * and with @in being the extension name, @len is 0 and @user is
525 * valid. Note though at this time the ESTABLISHED callback hasn't
526 * happened yet so if you initialize @user content there, @user
527 * content during this callback might not be useful for anything.
528 * Notice this callback comes to protocols[0].
530 * LWS_CALLBACK_CLIENT_CONFIRM_EXTENSION_SUPPORTED: When a client
531 * connection is being prepared to start a handshake to a server,
532 * each supported extension is checked with protocols[0] callback
533 * with this reason, giving the user code a chance to suppress the
534 * claim to support that extension by returning non-zero. If
535 * unhandled, by default 0 will be returned and the extension
536 * support included in the header to the server. Notice this
537 * callback comes to protocols[0].
539 * LWS_CALLBACK_PROTOCOL_INIT: One-time call per protocol so it can
540 * do initial setup / allocations etc
542 * LWS_CALLBACK_PROTOCOL_DESTROY: One-time call per protocol indicating
543 * this protocol won't get used at all after this callback, the
544 * context is getting destroyed. Take the opportunity to
545 * deallocate everything that was allocated by the protocol.
547 * The next four reasons are optional and only need taking care of if you
548 * will be integrating libwebsockets sockets into an external polling
551 * LWS_CALLBACK_ADD_POLL_FD: libwebsocket deals with its poll() loop
552 * internally, but in the case you are integrating with another
553 * server you will need to have libwebsocket sockets share a
554 * polling array with the other server. This and the other
555 * POLL_FD related callbacks let you put your specialized
556 * poll array interface code in the callback for protocol 0, the
557 * first protocol you support, usually the HTTP protocol in the
558 * serving case. This callback happens when a socket needs to be
559 * added to the polling loop: @user contains the fd, and
560 * @len is the events bitmap (like, POLLIN). If you are using the
561 * internal polling loop (the "service" callback), you can just
562 * ignore these callbacks.
564 * LWS_CALLBACK_DEL_POLL_FD: This callback happens when a socket descriptor
565 * needs to be removed from an external polling array. @user is
566 * the socket desricptor. If you are using the internal polling
567 * loop, you can just ignore it.
569 * LWS_CALLBACK_SET_MODE_POLL_FD: This callback happens when libwebsockets
570 * wants to modify the events for the socket descriptor in @user.
571 * The handler should OR @len on to the events member of the pollfd
572 * struct for this socket descriptor. If you are using the
573 * internal polling loop, you can just ignore it.
575 * LWS_CALLBACK_CLEAR_MODE_POLL_FD: This callback occurs when libwebsockets
576 * wants to modify the events for the socket descriptor in @user.
577 * The handler should AND ~@len on to the events member of the
578 * pollfd struct for this socket descriptor. If you are using the
579 * internal polling loop, you can just ignore it.
581 LWS_EXTERN int callback(struct libwebsocket_context * context,
582 struct libwebsocket *wsi,
583 enum libwebsocket_callback_reasons reason, void *user,
584 void *in, size_t len);
586 typedef int (callback_function)(struct libwebsocket_context * context,
587 struct libwebsocket *wsi,
588 enum libwebsocket_callback_reasons reason, void *user,
589 void *in, size_t len);
591 #ifndef LWS_NO_EXTENSIONS
593 * extension_callback_function() - Hooks to allow extensions to operate
594 * @context: Websockets context
595 * @ext: This extension
596 * @wsi: Opaque websocket instance pointer
597 * @reason: The reason for the call
598 * @user: Pointer to per-session user data allocated by library
599 * @in: Pointer used for some callback reasons
600 * @len: Length set for some callback reasons
602 * Each extension that is active on a particular connection receives
603 * callbacks during the connection lifetime to allow the extension to
604 * operate on websocket data and manage itself.
606 * Libwebsockets takes care of allocating and freeing "user" memory for
607 * each active extension on each connection. That is what is pointed to
608 * by the @user parameter.
610 * LWS_EXT_CALLBACK_CONSTRUCT: called when the server has decided to
611 * select this extension from the list provided by the client,
612 * just before the server will send back the handshake accepting
613 * the connection with this extension active. This gives the
614 * extension a chance to initialize its connection context found
617 * LWS_EXT_CALLBACK_CLIENT_CONSTRUCT: same as LWS_EXT_CALLBACK_CONSTRUCT
618 * but called when client is instantiating this extension. Some
619 * extensions will work the same on client and server side and then
620 * you can just merge handlers for both CONSTRUCTS.
622 * LWS_EXT_CALLBACK_DESTROY: called when the connection the extension was
623 * being used on is about to be closed and deallocated. It's the
624 * last chance for the extension to deallocate anything it has
625 * allocated in the user data (pointed to by @user) before the
626 * user data is deleted. This same callback is used whether you
627 * are in client or server instantiation context.
629 * LWS_EXT_CALLBACK_PACKET_RX_PREPARSE: when this extension was active on
630 * a connection, and a packet of data arrived at the connection,
631 * it is passed to this callback to give the extension a chance to
632 * change the data, eg, decompress it. @user is pointing to the
633 * extension's private connection context data, @in is pointing
634 * to an lws_tokens struct, it consists of a char * pointer called
635 * token, and an int called token_len. At entry, these are
636 * set to point to the received buffer and set to the content
637 * length. If the extension will grow the content, it should use
638 * a new buffer allocated in its private user context data and
639 * set the pointed-to lws_tokens members to point to its buffer.
641 * LWS_EXT_CALLBACK_PACKET_TX_PRESEND: this works the same way as
642 * LWS_EXT_CALLBACK_PACKET_RX_PREPARSE above, except it gives the
643 * extension a chance to change websocket data just before it will
644 * be sent out. Using the same lws_token pointer scheme in @in,
645 * the extension can change the buffer and the length to be
646 * transmitted how it likes. Again if it wants to grow the
647 * buffer safely, it should copy the data into its own buffer and
648 * set the lws_tokens token pointer to it.
650 LWS_EXTERN int extension_callback(struct libwebsocket_context * context,
651 struct libwebsocket_extension *ext,
652 struct libwebsocket *wsi,
653 enum libwebsocket_extension_callback_reasons reason, void *user,
654 void *in, size_t len);
656 typedef int (extension_callback_function)(struct libwebsocket_context * context,
657 struct libwebsocket_extension *ext,
658 struct libwebsocket *wsi,
659 enum libwebsocket_extension_callback_reasons reason, void *user,
660 void *in, size_t len);
664 * struct libwebsocket_protocols - List of protocols and handlers server
666 * @name: Protocol name that must match the one given in the client
667 * Javascript new WebSocket(url, 'protocol') name
668 * @callback: The service callback used for this protocol. It allows the
669 * service action for an entire protocol to be encapsulated in
670 * the protocol-specific callback
671 * @per_session_data_size: Each new connection using this protocol gets
672 * this much memory allocated on connection establishment and
673 * freed on connection takedown. A pointer to this per-connection
674 * allocation is passed into the callback in the 'user' parameter
675 * @rx_buffer_size: if you want atomic frames delivered to the callback, you
676 * should set this to the size of the biggest legal frame that
677 * you support. If the frame size is exceeded, there is no
678 * error, but the buffer will spill to the user callback when
679 * full, which you can detect by using
680 * libwebsockets_remaining_packet_payload(). Notice that you
681 * just talk about frame size here, the LWS_SEND_BUFFER_PRE_PADDING
682 * and post-padding are automatically also allocated on top.
683 * @owning_server: the server init call fills in this opaque pointer when
684 * registering this protocol with the server.
685 * @protocol_index: which protocol we are starting from zero
687 * This structure represents one protocol supported by the server. An
688 * array of these structures is passed to libwebsocket_create_server()
689 * allows as many protocols as you like to be handled by one server.
692 struct libwebsocket_protocols {
694 callback_function *callback;
695 size_t per_session_data_size;
696 size_t rx_buffer_size;
699 * below are filled in on server init and can be left uninitialized,
700 * no need for user to use them directly either
703 struct libwebsocket_context *owning_server;
707 #ifndef LWS_NO_EXTENSIONS
709 * struct libwebsocket_extension - An extension we know how to cope with
711 * @name: Formal extension name, eg, "deflate-stream"
712 * @callback: Service callback
713 * @per_session_data_size: Libwebsockets will auto-malloc this much
714 * memory for the use of the extension, a pointer
715 * to it comes in the @user callback parameter
716 * @per_context_private_data: Optional storage for this extension that
717 * is per-context, so it can track stuff across
718 * all sessions, etc, if it wants
721 struct libwebsocket_extension {
723 extension_callback_function *callback;
724 size_t per_session_data_size;
725 void * per_context_private_data;
730 * struct lws_context_creation_info: parameters to create context with
732 * @port: Port to listen on... you can use 0 to suppress listening on
733 * any port, that's what you want if you are not running a
734 * websocket server at all but just using it as a client
735 * @interface: NULL to bind the listen socket to all interfaces, or the
736 * interface name, eg, "eth2"
737 * @protocols: Array of structures listing supported protocols and a protocol-
738 * specific callback for each one. The list is ended with an
739 * entry that has a NULL callback pointer.
740 * It's not const because we write the owning_server member
741 * @extensions: NULL or array of libwebsocket_extension structs listing the
742 * extensions this context supports. If you configured with
743 * --without-extensions, you should give NULL here.
744 * @ssl_cert_filepath: If libwebsockets was compiled to use ssl, and you want
745 * to listen using SSL, set to the filepath to fetch the
746 * server cert from, otherwise NULL for unencrypted
747 * @ssl_private_key_filepath: filepath to private key if wanting SSL mode,
749 * @ssl_ca_filepath: CA certificate filepath or NULL
750 * @gid: group id to change to after setting listen socket, or -1.
751 * @uid: user id to change to after setting listen socket, or -1.
752 * @options: 0, or LWS_SERVER_OPTION_DEFEAT_CLIENT_MASK
753 * @user: optional user pointer that can be recovered via the context
754 * pointer using libwebsocket_context_user
755 * @ka_time: 0 for no keepalive, otherwise apply this keepalive timeout to
756 * all libwebsocket sockets, client or server
757 * @ka_probes: if ka_time was nonzero, after the timeout expires how many
758 * times to try to get a response from the peer before giving up
759 * and killing the connection
760 * @ka_interval: if ka_time was nonzero, how long to wait before each ka_probes
764 struct lws_context_creation_info {
766 const char *interface;
767 struct libwebsocket_protocols *protocols;
768 struct libwebsocket_extension *extensions;
769 const char *ssl_cert_filepath;
770 const char *ssl_private_key_filepath;
771 const char *ssl_ca_filepath;
774 unsigned int options;
783 void lws_set_log_level(int level, void (*log_emit_function)(int level, const char *line));
786 lwsl_emit_syslog(int level, const char *line);
788 LWS_EXTERN struct libwebsocket_context *
789 libwebsocket_create_context(struct lws_context_creation_info *info);
792 libwebsocket_context_destroy(struct libwebsocket_context *context);
795 libwebsocket_service(struct libwebsocket_context *context, int timeout_ms);
798 libwebsocket_service_fd(struct libwebsocket_context *context,
799 struct pollfd *pollfd);
802 libwebsocket_context_user(struct libwebsocket_context *context);
807 * When sending with websocket protocol (LWS_WRITE_TEXT or LWS_WRITE_BINARY)
808 * the send buffer has to have LWS_SEND_BUFFER_PRE_PADDING bytes valid BEFORE
809 * buf, and LWS_SEND_BUFFER_POST_PADDING bytes valid AFTER (buf + len).
811 * This allows us to add protocol info before and after the data, and send as
812 * one packet on the network without payload copying, for maximum efficiency.
814 * So for example you need this kind of code to use libwebsocket_write with a
817 * char buf[LWS_SEND_BUFFER_PRE_PADDING + 128 + LWS_SEND_BUFFER_POST_PADDING];
819 * // fill your part of the buffer... for example here it's all zeros
820 * memset(&buf[LWS_SEND_BUFFER_PRE_PADDING], 0, 128);
822 * libwebsocket_write(wsi, &buf[LWS_SEND_BUFFER_PRE_PADDING], 128);
824 * When sending LWS_WRITE_HTTP, there is no protocol addition and you can just
825 * use the whole buffer without taking care of the above.
829 * this is the frame nonce plus two header plus 8 length
830 * there's an additional two for mux extension per mux nesting level
831 * 2 byte prepend on close will already fit because control frames cannot use
832 * the big length style
835 #define LWS_SEND_BUFFER_PRE_PADDING (4 + 10 + (2 * MAX_MUX_RECURSION))
836 #define LWS_SEND_BUFFER_POST_PADDING 4
839 libwebsocket_write(struct libwebsocket *wsi, unsigned char *buf, size_t len,
840 enum libwebsocket_write_protocol protocol);
843 libwebsockets_serve_http_file(struct libwebsocket_context *context,
844 struct libwebsocket *wsi, const char *file,
845 const char *content_type);
847 libwebsockets_serve_http_file_fragment(struct libwebsocket_context *context,
848 struct libwebsocket *wsi);
850 LWS_EXTERN const struct libwebsocket_protocols *
851 libwebsockets_get_protocol(struct libwebsocket *wsi);
854 libwebsocket_callback_on_writable(struct libwebsocket_context *context,
855 struct libwebsocket *wsi);
858 libwebsocket_callback_on_writable_all_protocol(
859 const struct libwebsocket_protocols *protocol);
862 libwebsocket_get_socket_fd(struct libwebsocket *wsi);
865 libwebsocket_is_final_fragment(struct libwebsocket *wsi);
867 LWS_EXTERN unsigned char
868 libwebsocket_get_reserved_bits(struct libwebsocket *wsi);
871 libwebsocket_ensure_user_space(struct libwebsocket *wsi);
874 libwebsocket_rx_flow_control(struct libwebsocket *wsi, int enable);
877 libwebsockets_remaining_packet_payload(struct libwebsocket *wsi);
879 LWS_EXTERN struct libwebsocket *
880 libwebsocket_client_connect(struct libwebsocket_context *clients,
887 const char *protocol,
888 int ietf_version_or_minus_one);
890 LWS_EXTERN struct libwebsocket *
891 libwebsocket_client_connect_extended(struct libwebsocket_context *clients,
898 const char *protocol,
899 int ietf_version_or_minus_one,
902 LWS_EXTERN const char *
903 libwebsocket_canonical_hostname(struct libwebsocket_context *context);
907 libwebsockets_get_peer_addresses(struct libwebsocket_context *context,
908 struct libwebsocket *wsi, int fd, char *name, int name_len,
909 char *rip, int rip_len);
912 libwebsockets_hangup_on_client(struct libwebsocket_context *context, int fd);
915 libwebsocket_close_and_free_session(struct libwebsocket_context *context,
916 struct libwebsocket *wsi, enum lws_close_status);
919 libwebsockets_get_random(struct libwebsocket_context *context,
923 lws_daemonize(const char *_lock_path);
926 lws_send_pipe_choked(struct libwebsocket *wsi);
929 lws_frame_is_binary(struct libwebsocket *wsi);
931 LWS_EXTERN unsigned char *
932 libwebsockets_SHA1(const unsigned char *d, size_t n, unsigned char *md);
935 lws_b64_encode_string(const char *in, int in_len, char *out, int out_size);
938 lws_b64_decode_string(const char *in, char *out, int out_size);
940 LWS_EXTERN const char *
941 lws_get_library_version(void);
943 /* access to headers... only valid while headers valid */
946 lws_hdr_total_length(struct libwebsocket *wsi, enum lws_token_indexes h);
949 lws_hdr_copy(struct libwebsocket *wsi, char *dest, int len, enum lws_token_indexes h);
952 * Note: this is not normally needed as a user api. It's provided in case it is
953 * useful when integrating with other app poll loop service code.
957 libwebsocket_read(struct libwebsocket_context *context,
958 struct libwebsocket *wsi,
959 unsigned char *buf, size_t len);
961 #ifndef LWS_NO_EXTENSIONS
962 LWS_EXTERN struct libwebsocket_extension libwebsocket_internal_extensions[];