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1 package de.webman.util.security;
2
3
4 import java.security.*;
5
6
7
13 public class EncryptUtil
14 {
15
16
17
21 private static final String  [] BASE64_CHAR = {
22 "A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O", "P",
23 "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z", "a", "b", "c", "d", "e", "f",
24 "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v",
25 "w", "x", "y", "z", "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "+", "/"
26 };
27
28
31 private static final int[] DEC64 = {
32 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
33 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
34 -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, -1, -1, 63,
35 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1,
36 -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,
37 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1,
38 -1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
39 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1, -1, -1, -1
40 };
41
42
47 private static String encodeBase64(String str) {
48 byte[] dig = str.getBytes();
49 StringBuffer buf = new StringBuffer ();
50
51 int f0 = 0;
52 int r = 0;
53 int state = 0;
54 int j = 0;
55 int d0 = 0;
56 while (j < dig.length) {
57 switch (state) {
58 case 0:
59 d0 = (dig[j] >= 0) ? dig[j] : 256 + dig[j];
60 f0 = d0 & 0x3f;
61 r = (d0 & 0xc0) >> 6;
62 state = 1;
63 j++;
64 break;
65 case 1:
66 d0 = (dig[j] >= 0) ? dig[j] : 256 + dig[j];
67 f0 = r | (d0 & 0x0f) << 2;
68 r = (d0 & 0xf0) >> 4;
69 state = 2;
70 j++;
71 break;
72 case 2:
73 d0 = (dig[j] >= 0) ? dig[j] : 256 + dig[j];
74 f0 = r | (d0 & 0x03) << 4;
75 r = (d0 & 0xfc) >> 2;
76 state = 3;
77 j++;
78 break;
79 case 3:
80 f0 = r;
81 r = 0;
82 state = 0;
83 break;
84 }
85
86 buf.append(BASE64_CHAR[f0]);
87 }
88
89 if (state != 0)
90 buf.append (BASE64_CHAR[r]);
91
92 return buf.toString();
93 }
94
95
100 private static String decodeBase64(String str) {
101 byte[] dig = str.getBytes();
102 StringBuffer buf = new StringBuffer ();
103 int rc = 0;
104 int r = 0;
105 int f0 = 0;
106 int d0 = 0;
107 int d1 = 0;
108 int state = 0;
109 for (int j = 0; j < dig.length; j++) {
110 switch (state) {
111 case 0:
112 r = DEC64[(dig[j] >= 0) ? dig[j] : 256 + dig[j]];
113 f0 = -1;
114 state = 1;
115 break;
116 case 1:
117 d0 = DEC64[(dig[j] >= 0) ? dig[j] : 256 + dig[j]];
118 f0 = r | ((d0 & 0x03) << 6);
119 r = (d0 & 0x3c) >> 2;
120 state = 2;
121 break;
122 case 2:
123 d0 = DEC64[(dig[j] >= 0) ? dig[j] : 256 + dig[j]];
124 f0 = r | ((d0 & 0x0f) << 4);
125 r = (d0 & 0x30) >> 4;
126 state = 3;
127 break;
128 case 3:
129 d0 = DEC64[(dig[j] >= 0) ? dig[j] : 256 + dig[j]];
130 f0 = r | (d0 << 2);
131 r = 0;
132 state = 0;
133 break;
134 }
135
136 if (f0 > 0)
137 buf.append((char)f0);
138 }
139
140 if (state != 0 && r > 0)
141 buf.append((char)r);
142
143 return buf.toString();
144 }
145
146
151 public static String encrypt(String str) {
152 if (str != null)
153 return encodeBase64(new Encrypter().encrypt(str));
154 return null;
155 }
156
157
162 public static String decrypt(String str) {
163 if (str != null)
164 return new Encrypter().decrypt(decodeBase64(str));
165 return null;
166 }
167
168
172 public static void main(String [] args) {
173
174 for (int i = 0; i < args.length; i++) {
175 System.out.println("[" + EncryptUtil.encrypt(args[i]) + "]");
176 }
177
178 }
179
180
181
182
183 }
184
185
186
187
188 class Encrypter {
189 private static final int C1 = 21777;
190 private static final int C2 = 31709;
191
192 private int r = 42173;
193
194 public int enc(byte b) {
195 return enc((b >= 0) ? b : 256 + b);
196 }
197
198 public int dec(byte b) {
199 return dec((b >= 0) ? b : 256 + b);
200 }
201
202 public int enc(int plain) {
203 int cipher = plain ^ (r >> 8);
204 r = ((cipher + r) * C1 + C2) & 0xffff;
205 return cipher;
206 }
207
208 public int dec(int cipher) {
209 int plain = cipher ^ (r >> 8);
210 r = ((cipher + r) * C1 + C2) & 0xffff;
211 return plain;
212 }
213
214 public String encrypt(String str) {
215 StringBuffer buf = new StringBuffer ();
216 byte b[] = str.getBytes();
217
218 for (int i = 0; i < b.length; i++) {
219 buf.append((char)enc(b[i]));
220 }
221
222 return buf.toString();
223 }
224
225 public String decrypt(String str) {
226 byte[] b = str.getBytes();
227 StringBuffer buf = new StringBuffer ();
228
229 for (int i = 0; i < b.length; i++) {
230 buf.append ((char)dec(b[i]));
231 }
232 return buf.toString();
233 }
234 }
235 |
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