J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Portions Copyright 2000-2003 Sun Microsystems, Inc. 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. Sun designates this |
| 8 | * particular file as subject to the "Classpath" exception as provided |
| 9 | * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| 22 | * CA 95054 USA or visit www.sun.com if you need additional information or |
| 23 | * have any 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 java.io.*; |
| 35 | import java.net.*; |
| 36 | |
| 37 | public class TCPClient { |
| 38 | |
| 39 | private Socket tcpSocket; |
| 40 | private BufferedOutputStream out; |
| 41 | private BufferedInputStream in; |
| 42 | |
| 43 | public TCPClient(String hostname, int port) throws IOException { |
| 44 | tcpSocket = new Socket(hostname, port); |
| 45 | out = new BufferedOutputStream(tcpSocket.getOutputStream()); |
| 46 | in = new BufferedInputStream(tcpSocket.getInputStream()); |
| 47 | } |
| 48 | |
| 49 | public void send(byte[] data) throws IOException { |
| 50 | byte[] lenField = new byte[4]; |
| 51 | intToNetworkByteOrder(data.length, lenField, 0, 4); |
| 52 | out.write(lenField); |
| 53 | |
| 54 | out.write(data); |
| 55 | out.flush(); |
| 56 | } |
| 57 | |
| 58 | public byte[] receive() throws IOException { |
| 59 | byte[] lenField = new byte[4]; |
| 60 | int count = readFully(lenField, 4); |
| 61 | |
| 62 | if (count != 4) { |
| 63 | if (Krb5.DEBUG) { |
| 64 | System.out.println( |
| 65 | ">>>DEBUG: TCPClient could not read length field"); |
| 66 | } |
| 67 | return null; |
| 68 | } |
| 69 | |
| 70 | int len = networkByteOrderToInt(lenField, 0, 4); |
| 71 | if (Krb5.DEBUG) { |
| 72 | System.out.println( |
| 73 | ">>>DEBUG: TCPClient reading " + len + " bytes"); |
| 74 | } |
| 75 | if (len <= 0) { |
| 76 | if (Krb5.DEBUG) { |
| 77 | System.out.println( |
| 78 | ">>>DEBUG: TCPClient zero or negative length field: "+len); |
| 79 | } |
| 80 | return null; |
| 81 | } |
| 82 | |
| 83 | byte data[] = new byte[len]; |
| 84 | count = readFully(data, len); |
| 85 | if (count != len) { |
| 86 | if (Krb5.DEBUG) { |
| 87 | System.out.println( |
| 88 | ">>>DEBUG: TCPClient could not read complete packet (" + |
| 89 | len + "/" + count + ")"); |
| 90 | } |
| 91 | return null; |
| 92 | } else { |
| 93 | return data; |
| 94 | } |
| 95 | } |
| 96 | |
| 97 | public void close() throws IOException { |
| 98 | tcpSocket.close(); |
| 99 | } |
| 100 | |
| 101 | /** |
| 102 | * Read requested number of bytes before returning. |
| 103 | * @return The number of bytes actually read; -1 if none read |
| 104 | */ |
| 105 | private int readFully(byte[] inBuf, int total) throws IOException { |
| 106 | int count, pos = 0; |
| 107 | |
| 108 | while (total > 0) { |
| 109 | count = in.read(inBuf, pos, total); |
| 110 | |
| 111 | if (count == -1) { |
| 112 | return (pos == 0? -1 : pos); |
| 113 | } |
| 114 | pos += count; |
| 115 | total -= count; |
| 116 | } |
| 117 | return pos; |
| 118 | } |
| 119 | |
| 120 | /** |
| 121 | * Returns the integer represented by 4 bytes in network byte order. |
| 122 | */ |
| 123 | private static final int networkByteOrderToInt(byte[] buf, int start, |
| 124 | int count) { |
| 125 | if (count > 4) { |
| 126 | throw new IllegalArgumentException( |
| 127 | "Cannot handle more than 4 bytes"); |
| 128 | } |
| 129 | |
| 130 | int answer = 0; |
| 131 | |
| 132 | for (int i = 0; i < count; i++) { |
| 133 | answer <<= 8; |
| 134 | answer |= ((int)buf[start+i] & 0xff); |
| 135 | } |
| 136 | return answer; |
| 137 | } |
| 138 | |
| 139 | /** |
| 140 | * Encodes an integer into 4 bytes in network byte order in the buffer |
| 141 | * supplied. |
| 142 | */ |
| 143 | private static final void intToNetworkByteOrder(int num, byte[] buf, |
| 144 | int start, int count) { |
| 145 | if (count > 4) { |
| 146 | throw new IllegalArgumentException( |
| 147 | "Cannot handle more than 4 bytes"); |
| 148 | } |
| 149 | |
| 150 | for (int i = count-1; i >= 0; i--) { |
| 151 | buf[start+i] = (byte)(num & 0xff); |
| 152 | num >>>= 8; |
| 153 | } |
| 154 | } |
| 155 | } |