1 /*
2 * Copyright (c) 2000, 2013, 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. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 /*
27 *
28 * (C) Copyright IBM Corp. 1999 All Rights Reserved.
29 * Copyright 1997 The Open Group Research Institute. All rights reserved.
30 */
31
32 package sun.security.krb5.internal;
33
34 import sun.misc.IOUtils;
35
36 import java.io.*;
37 import java.net.*;
38
39 public abstract class NetClient implements AutoCloseable {
40 public static NetClient getInstance(String protocol, String hostname, int port,
41 int timeout) throws IOException {
42 if (protocol.equals("TCP")) {
43 return new TCPClient(hostname, port, timeout);
44 } else {
45 return new UDPClient(hostname, port, timeout);
46 }
47 }
48
49 abstract public void send(byte[] data) throws IOException;
50 abstract public byte[] receive() throws IOException;
51 abstract public void close() throws IOException;
52 }
53
54 class TCPClient extends NetClient {
55
56 private Socket tcpSocket;
57 private BufferedOutputStream out;
58 private BufferedInputStream in;
59
60 TCPClient(String hostname, int port, int timeout)
61 throws IOException {
62 tcpSocket = new Socket();
63 tcpSocket.connect(new InetSocketAddress(hostname, port), timeout);
64 out = new BufferedOutputStream(tcpSocket.getOutputStream());
65 in = new BufferedInputStream(tcpSocket.getInputStream());
66 tcpSocket.setSoTimeout(timeout);
67 }
68
69 @Override
70 public void send(byte[] data) throws IOException {
71 byte[] lenField = new byte[4];
72 intToNetworkByteOrder(data.length, lenField, 0, 4);
73 out.write(lenField);
74
75 out.write(data);
76 out.flush();
77 }
78
79 @Override
80 public byte[] receive() throws IOException {
81 byte[] lenField = new byte[4];
82 int count = readFully(lenField, 4);
83
84 if (count != 4) {
85 if (Krb5.DEBUG) {
86 System.out.println(
87 ">>>DEBUG: TCPClient could not read length field");
88 }
89 return null;
90 }
91
92 int len = networkByteOrderToInt(lenField, 0, 4);
93 if (Krb5.DEBUG) {
94 System.out.println(
95 ">>>DEBUG: TCPClient reading " + len + " bytes");
96 }
97 if (len <= 0) {
98 if (Krb5.DEBUG) {
99 System.out.println(
100 ">>>DEBUG: TCPClient zero or negative length field: "+len);
101 }
102 return null;
103 }
104
105 try {
106 return IOUtils.readFully(in, len, true);
107 } catch (IOException ioe) {
108 if (Krb5.DEBUG) {
109 System.out.println(
110 ">>>DEBUG: TCPClient could not read complete packet (" +
111 len + "/" + count + ")");
112 }
113 return null;
114 }
115 }
116
117 @Override
118 public void close() throws IOException {
119 tcpSocket.close();
120 }
121
122 /**
123 * Read requested number of bytes before returning.
124 * @return The number of bytes actually read; -1 if none read
125 */
126 private int readFully(byte[] inBuf, int total) throws IOException {
127 int count, pos = 0;
128
129 while (total > 0) {
130 count = in.read(inBuf, pos, total);
131
132 if (count == -1) {
133 return (pos == 0? -1 : pos);
134 }
135 pos += count;
136 total -= count;
137 }
138 return pos;
139 }
140
141 /**
142 * Returns the integer represented by 4 bytes in network byte order.
143 */
144 private static int networkByteOrderToInt(byte[] buf, int start,
145 int count) {
146 if (count > 4) {
147 throw new IllegalArgumentException(
148 "Cannot handle more than 4 bytes");
149 }
150
151 int answer = 0;
152
153 for (int i = 0; i < count; i++) {
154 answer <<= 8;
155 answer |= ((int)buf[start+i] & 0xff);
156 }
157 return answer;
158 }
159
160 /**
161 * Encodes an integer into 4 bytes in network byte order in the buffer
162 * supplied.
163 */
164 private static void intToNetworkByteOrder(int num, byte[] buf,
165 int start, int count) {
166 if (count > 4) {
167 throw new IllegalArgumentException(
168 "Cannot handle more than 4 bytes");
169 }
170
171 for (int i = count-1; i >= 0; i--) {
172 buf[start+i] = (byte)(num & 0xff);
173 num >>>= 8;
174 }
175 }
176 }
177
178 class UDPClient extends NetClient {
179 InetAddress iaddr;
180 int iport;
181 int bufSize = 65507;
182 DatagramSocket dgSocket;
183 DatagramPacket dgPacketIn;
184
185 UDPClient(String hostname, int port, int timeout)
186 throws UnknownHostException, SocketException {
187 iaddr = InetAddress.getByName(hostname);
188 iport = port;
189 dgSocket = new DatagramSocket();
190 dgSocket.setSoTimeout(timeout);
191 dgSocket.connect(iaddr, iport);
192 }
193
194 @Override
195 public void send(byte[] data) throws IOException {
196 DatagramPacket dgPacketOut = new DatagramPacket(data, data.length,
197 iaddr, iport);
198 dgSocket.send(dgPacketOut);
199 }
200
201 @Override
202 public byte[] receive() throws IOException {
203 byte[] ibuf = new byte[bufSize];
204 dgPacketIn = new DatagramPacket(ibuf, ibuf.length);
205 try {
206 dgSocket.receive(dgPacketIn);
207 }
208 catch (SocketException e) {
209 if (e instanceof PortUnreachableException) {
210 throw e;
211 }
212 dgSocket.receive(dgPacketIn);
213 }
214 byte[] data = new byte[dgPacketIn.getLength()];
215 System.arraycopy(dgPacketIn.getData(), 0, data, 0,
216 dgPacketIn.getLength());
217 return data;
218 }
219
220 @Override
221 public void close() {
222 dgSocket.close();
223 }
224 }