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16 package org.jmanage.core.crypto;
17
18 import org.jmanage.core.util.Loggers;
19 import org.jmanage.core.util.JManageProperties;
20
21 import javax.crypto.*;
22 import java.security.MessageDigest  ;
23 import java.security.NoSuchAlgorithmException ;
24 import java.util.logging.Logger ;
25
26
35 public class Crypto {
36
37 private static final Logger logger = Loggers.getLogger(Crypto.class);
38
39
40 private static final String hashAlgorithm =
41 JManageProperties.getHashAlgorithm();
42
43 private static Cipher encrypter;
44 private static Cipher decrypter;
45
46 public static void init(char[] password){
47 EncryptedKey encryptedKey = KeyManager.readKey(password);
48 SecretKey secretKey = encryptedKey.getSecretKey();
49 encrypter = getCipher(Cipher.ENCRYPT_MODE, secretKey);
50 assert encrypter != null;
51 decrypter = getCipher(Cipher.DECRYPT_MODE, secretKey);
52 assert decrypter != null;
53 logger.info("Crypto initialized");
54 }
55
56 public static synchronized byte[] encrypt(String plaintext){
57 try {
58 return encrypter.doFinal(plaintext.getBytes());
59 } catch (Exception e) {
60 throw new RuntimeException (e);
61 }
62 }
63
64 public static String encryptToString(String plaintext){
65 byte[] ciphertext = encrypt(plaintext);
66 return byteArrayToHexString(ciphertext);
67 }
68
69 public static synchronized byte[] decrypt(byte[] ciphertext){
70 try {
71 return decrypter.doFinal(ciphertext);
72 } catch (Exception e) {
73 throw new RuntimeException (e);
74 }
75 }
76
77 public static String decrypt(String ciphertext){
78 byte[] plaintext = decrypt(hexStringToByteArray(ciphertext));
79 return new String (plaintext);
80 }
81
82
88 public static String hash(String plaintext){
89 return hash(plaintext.toCharArray());
90 }
91
92 public static String hash(char[] plaintext){
93 try {
94 MessageDigest sha = MessageDigest.getInstance(hashAlgorithm);
95 byte[] hash = sha.digest(charArrayToByteArray(plaintext));
96 return byteArrayToHexString(hash);
97 } catch (NoSuchAlgorithmException e) {
98 throw new RuntimeException (e);
99 }
100 }
101
102 private static Cipher getCipher(int mode, SecretKey secretKey){
103
104 try {
105 Cipher cipher = Cipher.getInstance(EncryptedKey.CRYPTO_ALGORITHM);
106 cipher.init(mode, secretKey);
107 return cipher;
108 } catch (Exception e) {
109 throw new RuntimeException (e);
110 }
111 }
112
113 private static byte[] charArrayToByteArray(char[] array){
114 final byte[] output = new byte[array.length];
115 for(int i=0; i<output.length; i++){
116 output[i] = (byte) array[i];
117 }
118 return output;
119 }
120
121 private static String byteArrayToHexString(byte[] ba)
122 {
123 StringBuffer buffer = new StringBuffer (ba.length * 2);
124 int n = ba.length;
125 for (int i = 0; i < n; i++) {
126 byte b = ba[i];
127 appendASCII(b, buffer);
128 }
129 return buffer.toString();
130 }
131
132 private static byte[] hexStringToByteArray(String s) {
133 char[] ca = s.toCharArray();
134 int n_chars = ca.length;
135 byte[] ba = new byte[n_chars / 2];
136 int ci = 0;
137 int bi = 0;
138 while (ci < n_chars) {
139 char c = ca[ci++];
140 byte hi = hexCharToByte(c);
141 c = ca[ci++];
142 byte lo = hexCharToByte(c);
143 ba[bi++] = (byte) ((hi << 4) | lo);
144 }
145 return ba;
146 }
147
148 private static void appendASCII(byte b, StringBuffer buffer) {
149 byte hi = (byte) ((b >> 4) & 0xf);
150 byte lo = (byte) (b & 0xf);
151 buffer.append(hexByteToChar(hi));
152 buffer.append(hexByteToChar(lo));
153 }
154
155 private static char hexByteToChar(byte b) {
156 char c = 0;
157 switch (b)
158 {
159 case 0x0: c = '0'; break;
160 case 0x1: c = '1'; break;
161 case 0x2: c = '2'; break;
162 case 0x3: c = '3'; break;
163 case 0x4: c = '4'; break;
164 case 0x5: c = '5'; break;
165 case 0x6: c = '6'; break;
166 case 0x7: c = '7'; break;
167 case 0x8: c = '8'; break;
168 case 0x9: c = '9'; break;
169 case 0xa: c = 'a'; break;
170 case 0xb: c = 'b'; break;
171 case 0xc: c = 'c'; break;
172 case 0xd: c = 'd'; break;
173 case 0xe: c = 'e'; break;
174 case 0xf: c = 'f'; break;
175 default: assert false:"Bad byte digit of '" + c + "' received"; break;
176 }
177 return c;
178 }
179
180 private static byte hexCharToByte(char c) {
181 byte b = 0;
182 switch (c)
183 {
184 case '0': b = 0x0; break;
185 case '1': b = 0x1; break;
186 case '2': b = 0x2; break;
187 case '3': b = 0x3; break;
188 case '4': b = 0x4; break;
189 case '5': b = 0x5; break;
190 case '6': b = 0x6; break;
191 case '7': b = 0x7; break;
192 case '8': b = 0x8; break;
193 case '9': b = 0x9; break;
194 case 'a': case 'A': b = 0xa; break;
195 case 'b': case 'B': b = 0xb; break;
196 case 'c': case 'C': b = 0xc; break;
197 case 'd': case 'D': b = 0xd; break;
198 case 'e': case 'E': b = 0xe; break;
199 case 'f': case 'F': b = 0xf; break;
200 default: assert false:"Bad hex digit of '" + c + "' received"; break;
201 }
202 return b;
203 }
204 }
205 |
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