1 /*
2 * Copyright (c) 2016, 2017, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23
24 import java.io.Closeable;
25 import java.io.IOException;
26 import java.io.UncheckedIOException;
27 import java.net.InetSocketAddress;
28 import java.net.URI;
29 import java.nio.ByteBuffer;
30 import java.nio.CharBuffer;
31 import java.nio.channels.ClosedByInterruptException;
32 import java.nio.channels.ServerSocketChannel;
33 import java.nio.channels.SocketChannel;
34 import java.nio.charset.CharacterCodingException;
35 import java.security.MessageDigest;
36 import java.security.NoSuchAlgorithmException;
37 import java.util.ArrayList;
38 import java.util.Arrays;
39 import java.util.Base64;
40 import java.util.HashMap;
41 import java.util.Iterator;
42 import java.util.LinkedList;
43 import java.util.List;
44 import java.util.Map;
45 import java.util.concurrent.atomic.AtomicBoolean;
46 import java.util.function.Function;
47 import java.util.regex.Pattern;
48 import java.util.stream.Collectors;
49
50 import static java.lang.String.format;
51 import static java.lang.System.err;
52 import static java.nio.charset.StandardCharsets.ISO_8859_1;
53 import static java.util.Arrays.asList;
54 import static java.util.Objects.requireNonNull;
55
56 /**
57 * Dummy WebSocket Server.
58 *
59 * Performs simpler version of the WebSocket Opening Handshake over HTTP (i.e.
60 * no proxying, cookies, etc.) Supports sequential connections, one at a time,
61 * i.e. in order for a client to connect to the server the previous client must
62 * disconnect first.
63 *
64 * Expected client request:
65 *
66 * GET /chat HTTP/1.1
67 * Host: server.example.com
68 * Upgrade: websocket
69 * Connection: Upgrade
70 * Sec-WebSocket-Key: dGhlIHNhbXBsZSBub25jZQ==
71 * Origin: http://example.com
72 * Sec-WebSocket-Protocol: chat, superchat
73 * Sec-WebSocket-Version: 13
74 *
75 * This server response:
76 *
77 * HTTP/1.1 101 Switching Protocols
78 * Upgrade: websocket
79 * Connection: Upgrade
80 * Sec-WebSocket-Accept: s3pPLMBiTxaQ9kYGzzhZRbK+xOo=
81 * Sec-WebSocket-Protocol: chat
82 */
83 public final class DummyWebSocketServer implements Closeable {
84
85 private final AtomicBoolean started = new AtomicBoolean();
86 private final Thread thread;
87 private volatile ServerSocketChannel ssc;
88 private volatile InetSocketAddress address;
89
90 public DummyWebSocketServer() {
91 this(defaultMapping());
92 }
93
94 public DummyWebSocketServer(Function<List<String>, List<String>> mapping) {
95 requireNonNull(mapping);
96 thread = new Thread(() -> {
97 try {
98 while (!Thread.currentThread().isInterrupted()) {
99 err.println("Accepting next connection at: " + ssc);
100 SocketChannel channel = ssc.accept();
101 err.println("Accepted: " + channel);
102 try {
103 channel.configureBlocking(true);
104 StringBuilder request = new StringBuilder();
105 if (!readRequest(channel, request)) {
106 throw new IOException("Bad request:" + request);
107 }
108 List<String> strings = asList(request.toString().split("\r\n"));
109 List<String> response = mapping.apply(strings);
110 writeResponse(channel, response);
111 // Read until the thread is interrupted or an error occurred
112 // or the input is shutdown
113 ByteBuffer b = ByteBuffer.allocate(1024);
114 while (channel.read(b) != -1) {
115 b.clear();
116 }
117 } catch (IOException e) {
118 err.println("Error in connection: " + channel + ", " + e);
119 } finally {
120 err.println("Closed: " + channel);
121 close(channel);
122 }
123 }
124 } catch (ClosedByInterruptException ignored) {
125 } catch (IOException e) {
126 err.println(e);
127 } finally {
128 close(ssc);
129 err.println("Stopped at: " + getURI());
130 }
131 });
132 thread.setName("DummyWebSocketServer");
133 thread.setDaemon(false);
134 }
135
136 public void open() throws IOException {
137 err.println("Starting");
138 if (!started.compareAndSet(false, true)) {
139 throw new IllegalStateException("Already started");
140 }
141 ssc = ServerSocketChannel.open();
142 try {
143 ssc.configureBlocking(true);
144 ssc.bind(new InetSocketAddress("localhost", 0));
145 address = (InetSocketAddress) ssc.getLocalAddress();
146 thread.start();
147 } catch (IOException e) {
148 close(ssc);
149 }
150 err.println("Started at: " + getURI());
151 }
152
153 @Override
154 public void close() {
155 err.println("Stopping: " + getURI());
156 thread.interrupt();
157 close(ssc);
158 }
159
160 URI getURI() {
161 if (!started.get()) {
162 throw new IllegalStateException("Not yet started");
163 }
164 return URI.create("ws://" + address.getHostName() + ":" + address.getPort());
165 }
166
167 private boolean readRequest(SocketChannel channel, StringBuilder request)
168 throws IOException
169 {
170 ByteBuffer buffer = ByteBuffer.allocate(512);
171 while (channel.read(buffer) != -1) {
172 // read the complete HTTP request headers, there should be no body
173 CharBuffer decoded;
174 buffer.flip();
175 try {
176 decoded = ISO_8859_1.newDecoder().decode(buffer);
177 } catch (CharacterCodingException e) {
178 throw new UncheckedIOException(e);
179 }
180 request.append(decoded);
181 if (Pattern.compile("\r\n\r\n").matcher(request).find())
182 return true;
183 buffer.clear();
184 }
185 return false;
186 }
187
188 private void writeResponse(SocketChannel channel, List<String> response)
189 throws IOException
190 {
191 String s = response.stream().collect(Collectors.joining("\r\n"))
192 + "\r\n\r\n";
193 ByteBuffer encoded;
194 try {
195 encoded = ISO_8859_1.newEncoder().encode(CharBuffer.wrap(s));
196 } catch (CharacterCodingException e) {
197 throw new UncheckedIOException(e);
198 }
199 while (encoded.hasRemaining()) {
200 channel.write(encoded);
201 }
202 }
203
204 private static Function<List<String>, List<String>> defaultMapping() {
205 return request -> {
206 List<String> response = new LinkedList<>();
207 Iterator<String> iterator = request.iterator();
208 if (!iterator.hasNext()) {
209 throw new IllegalStateException("The request is empty");
210 }
211 String statusLine = iterator.next();
212 if (!(statusLine.startsWith("GET /") && statusLine.endsWith(" HTTP/1.1"))) {
213 throw new IllegalStateException
214 ("Unexpected status line: " + request.get(0));
215 }
216 response.add("HTTP/1.1 101 Switching Protocols");
217 Map<String, List<String>> requestHeaders = new HashMap<>();
218 while (iterator.hasNext()) {
219 String header = iterator.next();
220 String[] split = header.split(": ");
221 if (split.length != 2) {
222 throw new IllegalStateException
223 ("Unexpected header: " + header
224 + ", split=" + Arrays.toString(split));
225 }
226 requestHeaders.computeIfAbsent(split[0], k -> new ArrayList<>()).add(split[1]);
227
228 }
229 if (requestHeaders.containsKey("Sec-WebSocket-Protocol")) {
230 throw new IllegalStateException("Subprotocols are not expected");
231 }
232 if (requestHeaders.containsKey("Sec-WebSocket-Extensions")) {
233 throw new IllegalStateException("Extensions are not expected");
234 }
235 expectHeader(requestHeaders, "Connection", "Upgrade");
236 response.add("Connection: Upgrade");
237 expectHeader(requestHeaders, "Upgrade", "websocket");
238 response.add("Upgrade: websocket");
239 expectHeader(requestHeaders, "Sec-WebSocket-Version", "13");
240 List<String> key = requestHeaders.get("Sec-WebSocket-Key");
241 if (key == null || key.isEmpty()) {
242 throw new IllegalStateException("Sec-WebSocket-Key is missing");
243 }
244 if (key.size() != 1) {
245 throw new IllegalStateException("Sec-WebSocket-Key has too many values : " + key);
246 }
247 MessageDigest sha1 = null;
248 try {
249 sha1 = MessageDigest.getInstance("SHA-1");
250 } catch (NoSuchAlgorithmException e) {
251 throw new InternalError(e);
252 }
253 String x = key.get(0) + "258EAFA5-E914-47DA-95CA-C5AB0DC85B11";
254 sha1.update(x.getBytes(ISO_8859_1));
255 String v = Base64.getEncoder().encodeToString(sha1.digest());
256 response.add("Sec-WebSocket-Accept: " + v);
257 return response;
258 };
259 }
260
261 protected static String expectHeader(Map<String, List<String>> headers,
262 String name,
263 String value) {
264 List<String> v = headers.get(name);
265 if (!v.contains(value)) {
266 throw new IllegalStateException(
267 format("Expected '%s: %s', actual: '%s: %s'",
268 name, value, name, v)
269 );
270 }
271 return value;
272 }
273
274 private static void close(AutoCloseable... acs) {
275 for (AutoCloseable ac : acs) {
276 try {
277 ac.close();
278 } catch (Exception ignored) { }
279 }
280 }
281 }