WebSocket implementation in WebKit

WebCore/websockets/WebSocketChannel.cpp

+/*
+ * Copyright (C) 2009 Google Inc.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "config.h"
+#include "WebSocketChannel.h"
+
+#include "CString.h"
+#include "Logging.h"
+#include "PlatformString.h"
+#include "ScriptExecutionContext.h"
+#include "SharedBuffer.h"
+#include "SocketStreamHandle.h"
+#include "StringHash.h"
+#include "WebSocketChannelClient.h"
+
+#include <wtf/HashMap.h>
+#include <wtf/Deque.h>
+
+#include "NotImplemented.h"
+
+#undef LOG
+#define LOG(channel, ...) do { fprintf(stderr, __VA_ARGS__); fprintf(stderr, "\n"); } while (0);
+
+namespace {
+
+bool CheckWebSocketHandshake(const WebCore::WebSocketRequest &req, const WebCore::WebSocketResponse& resp)
+{
+    if (!resp.isValidHeader()) {
+        LOG(Network, "Wrong response header");
+        return false;
+    }
+    if (req.origin() != resp.websocket_origin()) {
+        LOG(Network, "Mismatch origin: %s != %s", req.origin().utf8().data(), resp.websocket_origin().utf8().data());
+        return false;
+    }
+    if (req.location() != resp.websocket_location()) {
+        LOG(Network, "Mismatch location: %s != %s", req.location().utf8().data(), resp.websocket_location().utf8().data());
+        return false;
+    }
+    if (!req.protocol().isEmpty() && req.protocol() != resp.websocket_protocol()) {
+        LOG(Network, "Mismatch protocol: %s != %s", req.protocol().utf8().data(), resp.websocket_protocol().utf8().data());
+        return false;
+    }
+    return true;
+}
+
+}  // anonymous namespace
+
+namespace WebCore {
+
+WebSocketChannel::WebSocketChannel(ScriptExecutionContext* context, WebSocketChannelClient* client, const WebSocketRequest& request)
+        : m_context(context)
+        , m_client(client)
+        , m_request(request)
+        , m_handshaked(false)
+        , m_buffered_amount(0)
+        , m_buffer(SharedBuffer::create())
+{
+    // TODO(ukai): additional parameters?
+}
+
+WebSocketChannel::~WebSocketChannel()
+{
+}
+
+void WebSocketChannel::connect()
+{
+    LOG(Network, "WebSocketChannel %p connect", this);
+
+    // ??? defer connection in SocketStreamHandle
+    m_handle = SocketStreamHandle::create(m_request.url(), this);
+}
+
+bool WebSocketChannel::send(const String& msg)
+{
+    LOG(Network, "WebSocketChannel %p send %s", this, msg.utf8().data());
+    static const char frame_type[1] = {'\0'};
+    static const char frame_end[1] = {'\xff'};
+    RefPtr<SharedBuffer> buf(SharedBuffer::create());
+    buf->append(frame_type, sizeof(frame_type));
+    buf->append(msg.utf8().data(), msg.utf8().length());
+    buf->append(frame_end, sizeof(frame_end));
+    m_buffered_amount += buf->size();
+    return m_handle->send(buf->data(), buf->size());
+}
+
+unsigned long WebSocketChannel::bufferedAmount() const
+{
+    LOG(Network, "WebSocketChannel %p bufferedAmount", this);
+    return m_buffered_amount;
+}
+
+void WebSocketChannel::close()
+{
+    LOG(Network, "WebSocketChannel %p close", this);
+    if (m_handle.get()) {
+        m_handle->close();  // will call didClose()
+    }
+}
+
+void WebSocketChannel::didOpen(SocketStreamHandle* handle)
+{
+    LOG(Network, "WebSocketChannel %p didConnect", this);
+    ASSERT(handle == m_handle.get() || m_handle.get() == 0);
+    if (m_handle.get() == 0)
+        return;
+    const CString& request_message = m_request.flattenToString();
+    m_handle->send(request_message.data(), request_message.length());
+}
+
+void WebSocketChannel::didClose(SocketStreamHandle* handle)
+{
+    LOG(Network, "WebSocketChannel %p didClose", this);
+    ASSERT(handle == m_handle.get() || m_handle.get() == 0);
+    if (m_handle.get() == 0)
+        return;
+    m_handle = NULL;
+    WebSocketChannelClient* client = m_client;
+    m_client = NULL;
+    client->didClose();
+}
+
+void WebSocketChannel::didReceivedData(SocketStreamHandle* handle, const char* data, int len)
+{
+    LOG(Network, "WebSocketChannel %p didReceiveData %d", this, len);
+    ASSERT(handle == m_handle.get() || m_handle.get() == 0);
+    if (m_handle.get() == 0)
+        return;
+    m_buffer->append(data, len);
+    if (!m_handshaked) {
+        int header_len = m_response.readHandshakeResponse(m_buffer->data(), m_buffer->size());
+        if (header_len <= 0)
+            return;
+        m_handshaked = CheckWebSocketHandshake(m_request, m_response);
+        if (m_handshaked) {
+            LOG(Network, "WebSocketChannel %p connected", this);
+            m_client->didConnect();
+        } else {
+            LOG(Network, "WebSocketChannel %p connection failed", this);
+            didClose(handle);
+        }
+        if (header_len == len)
+            return;
+        RefPtr<SharedBuffer> buf(SharedBuffer::create());
+        buf->append(m_buffer->data() + header_len, m_buffer->size() - header_len);
+        m_buffer.swap(buf);
+    }
+    RefPtr<SharedBuffer> buf(SharedBuffer::create());
+    buf.swap(m_buffer);
+
+    const char *next_frame = buf->data();
+    const char *p = buf->data();
+    const char *end = p + buf->size();
+    while (p < end) {
+        unsigned char frame_byte = static_cast<unsigned char>(*p++);
+        if ((frame_byte & 0x80) == 0x80) {
+            // TODO(ukai): overflow check
+            int length = 0;
+            while (p < end && (*p & 0x80) == 0x80) {
+                length = length * 127 + *p & 0x7f;
+                ++p;
+            }
+            if (p + length < end) {
+                p += length;
+                next_frame = p;
+            }
+        } else {
+            const char *msg_start = p;
+            while (p < end && *p != '\xff') {
+                ++p;
+            }
+            if (p < end && *p == '\xff') {
+                if (frame_byte == 0x00)
+                    m_client->didReceiveMessage(String::fromUTF8(msg_start, p - msg_start));
+                ++p;
+                next_frame = p;
+            }
+        }
+    }
+    if (next_frame < end) {
+        m_buffer->append(next_frame, end - next_frame);
+    }
+}
+
+void WebSocketChannel::didFail(SocketStreamHandle* handle, const SocketStreamHandleError& err)
+{
+    LOG(Network, "WebSocketChannel %p didFaile", this);
+    ASSERT(handle == m_handle.get() || m_handle.get() == 0);
+    didClose(handle);
+}
+
+}  // namespace WebCore