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 #include "private-libwebsockets.h"
25 * -04 of the protocol (actually the 80th version) has a radically different
26 * handshake. The 04 spec gives the following idea
28 * The handshake from the client looks as follows:
31 * Host: server.example.com
34 * Sec-WebSocket-Key: dGhlIHNhbXBsZSBub25jZQ==
35 * Sec-WebSocket-Origin: http://example.com
36 * Sec-WebSocket-Protocol: chat, superchat
37 * Sec-WebSocket-Version: 4
39 * The handshake from the server looks as follows:
41 * HTTP/1.1 101 Switching Protocols
44 * Sec-WebSocket-Accept: me89jWimTRKTWwrS3aRrL53YZSo=
45 * Sec-WebSocket-Nonce: AQIDBAUGBwgJCgsMDQ4PEC==
46 * Sec-WebSocket-Protocol: chat
50 * We have to take care about parsing because the headers may be split
51 * into multiple fragments. They may contain unknown headers with arbitrary
52 * argument lengths. So, we parse using a single-character at a time state
53 * machine that is completely independent of packet size.
57 libwebsocket_read(struct libwebsocket_context *context,
58 struct libwebsocket *wsi, unsigned char *buf, size_t len)
64 case WSI_STATE_HTTP_BODY:
68 if (wsi->u.http.content_length_seen >= wsi->u.http.content_length)
71 wsi->u.http.post_buffer[wsi->u.http.body_index++] = *buf++;
72 wsi->u.http.content_length_seen++;
73 n = wsi->protocol->rx_buffer_size;
75 n = LWS_MAX_SOCKET_IO_BUF;
77 if (wsi->u.http.body_index != n &&
78 wsi->u.http.content_length_seen != wsi->u.http.content_length)
81 if (wsi->protocol->callback) {
82 n = wsi->protocol->callback(
83 wsi->protocol->owning_server, wsi,
84 LWS_CALLBACK_HTTP_BODY,
85 wsi->user_space, wsi->u.http.post_buffer,
86 wsi->u.http.body_index);
87 wsi->u.http.body_index = 0;
92 if (wsi->u.http.content_length_seen == wsi->u.http.content_length) {
93 /* he sent the content in time */
94 libwebsocket_set_timeout(wsi, NO_PENDING_TIMEOUT, 0);
95 n = wsi->protocol->callback(
96 wsi->protocol->owning_server, wsi,
97 LWS_CALLBACK_HTTP_BODY_COMPLETION,
98 wsi->user_space, NULL, 0);
99 wsi->u.http.body_index = 0;
107 * we need to spill here so everything is seen in the case
108 * there is no content-length
110 if (wsi->u.http.body_index && wsi->protocol->callback) {
111 n = wsi->protocol->callback(
112 wsi->protocol->owning_server, wsi,
113 LWS_CALLBACK_HTTP_BODY,
114 wsi->user_space, wsi->u.http.post_buffer,
115 wsi->u.http.body_index);
116 wsi->u.http.body_index = 0;
122 case WSI_STATE_HTTP_ISSUING_FILE:
124 wsi->state = WSI_STATE_HTTP_HEADERS;
125 wsi->u.hdr.parser_state = WSI_TOKEN_NAME_PART;
126 wsi->u.hdr.lextable_pos = 0;
128 case WSI_STATE_HTTP_HEADERS:
130 lwsl_parser("issuing %d bytes to parser\n", (int)len);
132 if (lws_handshake_client(wsi, &buf, len))
135 switch (lws_handshake_server(context, wsi, &buf, len)) {
143 case WSI_STATE_AWAITING_CLOSE_ACK:
144 case WSI_STATE_ESTABLISHED:
145 if (lws_handshake_client(wsi, &buf, len))
148 case LWS_CONNMODE_WS_SERVING:
150 if (libwebsocket_interpret_incoming_packet(wsi, buf, len) < 0) {
151 lwsl_info("interpret_incoming_packet has bailed\n");
158 lwsl_err("libwebsocket_read: Unhandled state\n");
165 lwsl_debug("closing connection at libwebsocket_read bail:\n");
167 libwebsocket_close_and_free_session(context, wsi,
168 LWS_CLOSE_STATUS_NOSTATUS);