001/*
002 * Sonar, open source software quality management tool.
003 * Copyright (C) 2008-2012 SonarSource
004 * mailto:contact AT sonarsource DOT com
005 *
006 * Sonar is free software; you can redistribute it and/or
007 * modify it under the terms of the GNU Lesser General Public
008 * License as published by the Free Software Foundation; either
009 * version 3 of the License, or (at your option) any later version.
010 *
011 * Sonar is distributed in the hope that it will be useful,
012 * but WITHOUT ANY WARRANTY; without even the implied warranty of
013 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014 * Lesser General Public License for more details.
015 *
016 * You should have received a copy of the GNU Lesser General Public
017 * License along with Sonar; if not, write to the Free Software
018 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02
019 */
020package org.sonar.api.config;
021
022import com.google.common.collect.ImmutableMap;
023
024import java.util.Locale;
025import java.util.Map;
026import java.util.regex.Matcher;
027import java.util.regex.Pattern;
028
029/**
030 * @since 3.0
031 */
032public final class Encryption {
033
034  private static final String BASE64_ALGORITHM = "b64";
035
036  private static final String AES_ALGORITHM = "aes";
037  private final AesCipher aesCipher;
038
039  private final Map<String, Cipher> ciphers;
040  private static final Pattern ENCRYPTED_PATTERN = Pattern.compile("\\{(.*?)\\}(.*)");
041
042  Encryption(Settings settings) {
043    aesCipher = new AesCipher(settings);
044    ciphers = ImmutableMap.of(
045        BASE64_ALGORITHM, new Base64Cipher(),
046        AES_ALGORITHM, aesCipher
047    );
048  }
049
050  /**
051   * Checks the availability of the secret key, that is required to encrypt and decrypt.
052   */
053  public boolean hasSecretKey() {
054    return aesCipher.hasSecretKey();
055  }
056
057  public boolean isEncrypted(String value) {
058    return value.indexOf('{')==0 && value.indexOf('}') > 1;
059  }
060
061  public String encrypt(String clearText) {
062    return encrypt(AES_ALGORITHM, clearText);
063  }
064
065  public String scramble(String clearText) {
066    return encrypt(BASE64_ALGORITHM, clearText);
067  }
068
069  public String generateRandomSecretKey() {
070    return aesCipher.generateRandomSecretKey();
071  }
072
073  public String decrypt(String encryptedText) {
074    Matcher matcher = ENCRYPTED_PATTERN.matcher(encryptedText);
075    if (matcher.matches()) {
076      Cipher cipher = ciphers.get(matcher.group(1).toLowerCase(Locale.ENGLISH));
077      if (cipher != null) {
078        return cipher.decrypt(matcher.group(2));
079      }
080    }
081    return encryptedText;
082  }
083
084  private String encrypt(String algorithm, String clearText) {
085    Cipher cipher = ciphers.get(algorithm);
086    if (cipher == null) {
087      throw new IllegalArgumentException("Unknown cipher algorithm: " + algorithm);
088    }
089    return String.format("{%s}%s", algorithm, cipher.encrypt(clearText));
090  }
091}