001    /**
002     * Copyright (c) 2000-present Liferay, Inc. All rights reserved.
003     *
004     * This library is free software; you can redistribute it and/or modify it under
005     * the terms of the GNU Lesser General Public License as published by the Free
006     * Software Foundation; either version 2.1 of the License, or (at your option)
007     * any later version.
008     *
009     * This library is distributed in the hope that it will be useful, but WITHOUT
010     * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
011     * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
012     * details.
013     */
014    
015    package com.liferay.portal.kernel.util;
016    
017    import com.liferay.portal.kernel.io.ProtectedObjectInputStream;
018    import com.liferay.portal.kernel.io.unsync.UnsyncByteArrayInputStream;
019    import com.liferay.portal.kernel.io.unsync.UnsyncByteArrayOutputStream;
020    import com.liferay.portal.kernel.log.Log;
021    import com.liferay.portal.kernel.log.LogFactoryUtil;
022    
023    import java.io.ObjectInputStream;
024    import java.io.ObjectOutputStream;
025    
026    /**
027     * @author Brian Wing Shun Chan
028     */
029    public class Base64 {
030    
031            public static byte[] decode(String base64) {
032                    if (Validator.isNull(base64)) {
033                            return new byte[0];
034                    }
035    
036                    int pad = 0;
037    
038                    for (int i = base64.length() - 1; base64.charAt(i) == CharPool.EQUAL;
039                            i--) {
040    
041                            pad++;
042                    }
043    
044                    int length = (base64.length() * 6) / 8 - pad;
045                    byte[] raw = new byte[length];
046                    int rawindex = 0;
047    
048                    for (int i = 0; i < base64.length(); i += 4) {
049                            int block = getValue(base64.charAt(i)) << 18;
050    
051                            block += getValue(base64.charAt(i + 1)) << 12;
052                            block += getValue(base64.charAt(i + 2)) << 6;
053                            block += getValue(base64.charAt(i + 3));
054    
055                            for (int j = 0; j < 3 && rawindex + j < raw.length; j++) {
056                                    raw[rawindex + j] = (byte)(block >> 8 * (2 - j) & 0xff);
057                            }
058    
059                            rawindex += 3;
060                    }
061    
062                    return raw;
063            }
064    
065            public static String encode(byte[] raw) {
066                    return encode(raw, 0, raw.length);
067            }
068    
069            public static String encode(byte[] raw, int offset, int length) {
070                    int lastIndex = Math.min(raw.length, offset + length);
071    
072                    StringBuilder sb = new StringBuilder(
073                            ((lastIndex - offset) / 3 + 1) * 4);
074    
075                    for (int i = offset; i < lastIndex; i += 3) {
076                            sb.append(encodeBlock(raw, i, lastIndex));
077                    }
078    
079                    return sb.toString();
080            }
081    
082            public static String fromURLSafe(String base64) {
083                    return StringUtil.replace(
084                            base64,
085                            new char[] {CharPool.MINUS, CharPool.STAR, CharPool.UNDERLINE},
086                            new char[] {CharPool.PLUS, CharPool.EQUAL, CharPool.SLASH});
087            }
088    
089            public static String objectToString(Object o) {
090                    if (o == null) {
091                            return null;
092                    }
093    
094                    UnsyncByteArrayOutputStream ubaos = new UnsyncByteArrayOutputStream(
095                            32000);
096    
097                    try (ObjectOutputStream os = new ObjectOutputStream(ubaos)) {
098                            os.writeObject(o);
099                    }
100                    catch (Exception e) {
101                            _log.error(e, e);
102                    }
103    
104                    return encode(ubaos.unsafeGetByteArray(), 0, ubaos.size());
105            }
106    
107            public static Object stringToObject(String s) {
108                    return _stringToObject(s, null, false);
109            }
110    
111            public static Object stringToObject(String s, ClassLoader classLoader) {
112                    return _stringToObject(s, classLoader, false);
113            }
114    
115            public static Object stringToObjectSilent(String s) {
116                    return _stringToObject(s, null, true);
117            }
118    
119            public static Object stringToObjectSilent(
120                    String s, ClassLoader classLoader) {
121    
122                    return _stringToObject(s, classLoader, true);
123            }
124    
125            public static String toURLSafe(String base64) {
126                    return StringUtil.replace(
127                            base64, new char[] {CharPool.PLUS, CharPool.EQUAL, CharPool.SLASH},
128                            new char[] {CharPool.MINUS, CharPool.STAR, CharPool.UNDERLINE});
129            }
130    
131            protected static char[] encodeBlock(byte[] raw, int offset, int lastIndex) {
132                    int block = 0;
133                    int slack = lastIndex - offset - 1;
134                    int end = slack < 2 ? slack : 2;
135    
136                    for (int i = 0; i <= end; i++) {
137                            byte b = raw[offset + i];
138    
139                            int neuter = b >= 0 ? ((int) (b)) : b + 256;
140                            block += neuter << 8 * (2 - i);
141                    }
142    
143                    char[] base64 = new char[4];
144    
145                    for (int i = 0; i < 4; i++) {
146                            int sixbit = block >>> 6 * (3 - i) & 0x3f;
147                            base64[i] = getChar(sixbit);
148                    }
149    
150                    if (slack < 1) {
151                            base64[2] = CharPool.EQUAL;
152                    }
153    
154                    if (slack < 2) {
155                            base64[3] = CharPool.EQUAL;
156                    }
157    
158                    return base64;
159            }
160    
161            protected static char getChar(int sixbit) {
162                    if ((sixbit >= 0) && (sixbit <= 25)) {
163                            return (char)(65 + sixbit);
164                    }
165    
166                    if ((sixbit >= 26) && (sixbit <= 51)) {
167                            return (char)(97 + (sixbit - 26));
168                    }
169    
170                    if ((sixbit >= 52) && (sixbit <= 61)) {
171                            return (char)(48 + (sixbit - 52));
172                    }
173    
174                    if (sixbit == 62) {
175                            return CharPool.PLUS;
176                    }
177    
178                    if (sixbit != 63) {
179                            return CharPool.QUESTION;
180                    }
181    
182                    return CharPool.SLASH;
183            }
184    
185            protected static int getValue(char c) {
186                    if ((c >= CharPool.UPPER_CASE_A) && (c <= CharPool.UPPER_CASE_Z)) {
187                            return c - 65;
188                    }
189    
190                    if ((c >= CharPool.LOWER_CASE_A) && (c <= CharPool.LOWER_CASE_Z)) {
191                            return (c - 97) + 26;
192                    }
193    
194                    if ((c >= CharPool.NUMBER_0) && (c <= CharPool.NUMBER_9)) {
195                            return (c - 48) + 52;
196                    }
197    
198                    if (c == CharPool.PLUS) {
199                            return 62;
200                    }
201    
202                    if (c == CharPool.SLASH) {
203                            return 63;
204                    }
205    
206                    if (c != CharPool.EQUAL) {
207                            return -1;
208                    }
209    
210                    return 0;
211            }
212    
213            private static Object _stringToObject(
214                    String s, ClassLoader classLoader, boolean silent) {
215    
216                    if (s == null) {
217                            return null;
218                    }
219    
220                    byte[] bytes = decode(s);
221    
222                    UnsyncByteArrayInputStream ubais = new UnsyncByteArrayInputStream(
223                            bytes);
224    
225                    try {
226                            ObjectInputStream is = null;
227    
228                            if (classLoader == null) {
229                                    is = new ProtectedObjectInputStream(ubais);
230                            }
231                            else {
232                                    is = new ProtectedClassLoaderObjectInputStream(
233                                            ubais, classLoader);
234                            }
235    
236                            return is.readObject();
237                    }
238                    catch (Exception e) {
239                            if (!silent) {
240                                    _log.error(e, e);
241                            }
242                    }
243    
244                    return null;
245            }
246    
247            private static final Log _log = LogFactoryUtil.getLog(Base64.class);
248    
249    }