001/* 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017package org.apache.wicket.util.crypt; 018 019import java.io.UnsupportedEncodingException; 020import java.security.GeneralSecurityException; 021import java.util.Base64; 022import java.util.UUID; 023 024import javax.crypto.Cipher; 025 026import org.slf4j.Logger; 027import org.slf4j.LoggerFactory; 028 029 030/** 031 * Abstract base class for JCE based ICrypt implementations. 032 * 033 * @author Juergen Donnerstag 034 */ 035public abstract class AbstractCrypt implements ICrypt 036{ 037 /** Encoding used to convert java String from and to byte[] */ 038 private static final String CHARACTER_ENCODING = "UTF-8"; 039 040 /** Log. */ 041 private static final Logger log = LoggerFactory.getLogger(AbstractCrypt.class); 042 043 /** Key used to de-/encrypt the data */ 044 private String encryptionKey; 045 046 /** 047 * Constructor 048 */ 049 public AbstractCrypt() 050 { 051 this.encryptionKey = UUID.randomUUID().toString(); 052 } 053 054 /** 055 * Decrypts a string into a string. 056 * 057 * @param text 058 * text to decrypt 059 * @return the decrypted text 060 */ 061 @Override 062 public final String decryptUrlSafe(final String text) 063 { 064 try 065 { 066 byte[] decoded = java.util.Base64.getUrlDecoder().decode(text); 067 return new String(decryptByteArray(decoded), CHARACTER_ENCODING); 068 } 069 catch (Exception ex) 070 { 071 log.debug("Error decoding text: " + text, ex); 072 return null; 073 } 074 } 075 076 /** 077 * Encrypt a string into a string using URL safe Base64 encoding. 078 * 079 * @param plainText 080 * text to encrypt 081 * @return encrypted string 082 */ 083 @Override 084 public final String encryptUrlSafe(final String plainText) 085 { 086 try 087 { 088 byte[] encrypted = encryptStringToByteArray(plainText); 089 Base64.Encoder encoder = Base64.getUrlEncoder().withoutPadding(); 090 byte[] encoded = encoder.encode(encrypted); 091 return new String(encoded, CHARACTER_ENCODING); 092 } 093 catch (GeneralSecurityException e) 094 { 095 log.error("Unable to encrypt text '" + plainText + "'", e); 096 return null; 097 } 098 catch (UnsupportedEncodingException e) 099 { 100 log.error("Unable to encrypt text '" + plainText + "'", e); 101 return null; 102 } 103 } 104 105 /** 106 * Get encryption private key 107 * 108 * @return encryption private key 109 */ 110 public String getKey() 111 { 112 return encryptionKey; 113 } 114 115 /** 116 * Set encryption private key 117 * 118 * @param key 119 * private key to make de-/encryption unique 120 */ 121 @Override 122 public void setKey(final String key) 123 { 124 encryptionKey = key; 125 } 126 127 /** 128 * Crypts the given byte array 129 * 130 * @param input 131 * byte array to be crypted 132 * @param mode 133 * crypt mode 134 * @return the input crypted. Null in case of an error 135 * @throws GeneralSecurityException 136 */ 137 protected abstract byte[] crypt(final byte[] input, final int mode) 138 throws GeneralSecurityException; 139 140 /** 141 * Decrypts an encrypted, but Base64 decoded byte array into a byte array. 142 * 143 * @param encrypted 144 * byte array to decrypt 145 * @return the decrypted text 146 */ 147 private byte[] decryptByteArray(final byte[] encrypted) 148 { 149 try 150 { 151 return crypt(encrypted, Cipher.DECRYPT_MODE); 152 } 153 catch (GeneralSecurityException e) 154 { 155 throw new RuntimeException( 156 "Unable to decrypt the text '" + new String(encrypted) + "'", e); 157 } 158 } 159 160 /** 161 * Encrypts the given text into a byte array. 162 * 163 * @param plainText 164 * text to encrypt 165 * @return the string encrypted 166 * @throws GeneralSecurityException 167 */ 168 private byte[] encryptStringToByteArray(final String plainText) 169 throws GeneralSecurityException 170 { 171 try 172 { 173 return crypt(plainText.getBytes(CHARACTER_ENCODING), Cipher.ENCRYPT_MODE); 174 } 175 catch (UnsupportedEncodingException ex) 176 { 177 throw new RuntimeException(ex.getMessage()); 178 } 179 } 180}