org.argeo.cms/src/org/argeo/cms/security/AbstractKeyring.java

   1 /*
   2  * Copyright (C) 2007-2012 Argeo GmbH
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  *         http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16 package org.argeo.cms.security;
  17
  18 import java.io.ByteArrayInputStream;
  19 import java.io.ByteArrayOutputStream;
  20 import java.io.CharArrayWriter;
  21 import java.io.IOException;
  22 import java.io.InputStream;
  23 import java.io.InputStreamReader;
  24 import java.io.OutputStreamWriter;
  25 import java.io.Reader;
  26 import java.io.Writer;
  27 import java.security.AccessController;
  28 import java.security.MessageDigest;
  29 import java.security.Provider;
  30 import java.security.Security;
  31 import java.util.Arrays;
  32 import java.util.Iterator;
  33
  34 import javax.crypto.SecretKey;
  35 import javax.security.auth.Subject;
  36 import javax.security.auth.callback.Callback;
  37 import javax.security.auth.callback.CallbackHandler;
  38 import javax.security.auth.callback.PasswordCallback;
  39 import javax.security.auth.callback.TextOutputCallback;
  40 import javax.security.auth.callback.UnsupportedCallbackException;
  41 import javax.security.auth.login.LoginContext;
  42 import javax.security.auth.login.LoginException;
  43
  44 import org.apache.commons.io.IOUtils;
  45 import org.argeo.cms.CmsException;
  46 import org.argeo.node.security.CryptoKeyring;
  47 import org.argeo.node.security.Keyring;
  48 import org.argeo.node.security.PBEKeySpecCallback;
  49
  50 /** username / password based keyring. TODO internationalize */
  51 public abstract class AbstractKeyring implements Keyring, CryptoKeyring {
  52         public final static String DEFAULT_KEYRING_LOGIN_CONTEXT = "KEYRING";
  53
  54         private String loginContextName = DEFAULT_KEYRING_LOGIN_CONTEXT;
  55         private CallbackHandler defaultCallbackHandler;
  56
  57         private String charset = "UTF-8";
  58
  59         /**
  60          * Default provider is bouncy castle, in order to have consistent behaviour
  61          * across implementations
  62          */
  63         private String securityProviderName = "BC";
  64
  65         /**
  66          * Whether the keyring has already been created in the past with a master
  67          * password
  68          */
  69         protected abstract Boolean isSetup();
  70
  71         /**
  72          * Setup the keyring persistently, {@link #isSetup()} must return true
  73          * afterwards
  74          */
  75         protected abstract void setup(char[] password);
  76
  77         /** Populates the key spec callback */
  78         protected abstract void handleKeySpecCallback(PBEKeySpecCallback pbeCallback);
  79
  80         protected abstract void encrypt(String path, InputStream unencrypted);
  81
  82         protected abstract InputStream decrypt(String path);
  83
  84         /** Triggers lazy initialization */
  85         protected SecretKey getSecretKey() {
  86                 Subject subject = Subject.getSubject(AccessController.getContext());
  87                 // we assume only one secrete key is available
  88                 Iterator<SecretKey> iterator = subject.getPrivateCredentials(SecretKey.class).iterator();
  89                 if (!iterator.hasNext()) {// not initialized
  90                         CallbackHandler callbackHandler = new KeyringCallbackHandler();
  91                         ClassLoader currentContextClassLoader = Thread.currentThread().getContextClassLoader();
  92                         Thread.currentThread().setContextClassLoader(getClass().getClassLoader());
  93                         try {
  94                                 LoginContext loginContext = new LoginContext(loginContextName, subject, callbackHandler);
  95                                 loginContext.login();
  96                                 // FIXME will login even if password is wrong
  97                                 iterator = subject.getPrivateCredentials(SecretKey.class).iterator();
  98                                 return iterator.next();
  99                         } catch (LoginException e) {
 100                                 throw new CmsException("Keyring login failed", e);
 101                         } finally {
 102                                 Thread.currentThread().setContextClassLoader(currentContextClassLoader);
 103                         }
 104
 105                 } else {
 106                         SecretKey secretKey = iterator.next();
 107                         if (iterator.hasNext())
 108                                 throw new CmsException("More than one secret key in private credentials");
 109                         return secretKey;
 110                 }
 111         }
 112
 113         public InputStream getAsStream(String path) {
 114                 return decrypt(path);
 115         }
 116
 117         public void set(String path, InputStream in) {
 118                 encrypt(path, in);
 119         }
 120
 121         public char[] getAsChars(String path) {
 122                 InputStream in = getAsStream(path);
 123                 CharArrayWriter writer = null;
 124                 Reader reader = null;
 125                 try {
 126                         writer = new CharArrayWriter();
 127                         reader = new InputStreamReader(in, charset);
 128                         IOUtils.copy(reader, writer);
 129                         return writer.toCharArray();
 130                 } catch (IOException e) {
 131                         throw new CmsException("Cannot decrypt to char array", e);
 132                 } finally {
 133                         IOUtils.closeQuietly(reader);
 134                         IOUtils.closeQuietly(in);
 135                         IOUtils.closeQuietly(writer);
 136                 }
 137         }
 138
 139         public void set(String path, char[] arr) {
 140                 ByteArrayOutputStream out = new ByteArrayOutputStream();
 141                 ByteArrayInputStream in = null;
 142                 Writer writer = null;
 143                 try {
 144                         writer = new OutputStreamWriter(out, charset);
 145                         writer.write(arr);
 146                         writer.flush();
 147                         in = new ByteArrayInputStream(out.toByteArray());
 148                         set(path, in);
 149                 } catch (IOException e) {
 150                         throw new CmsException("Cannot encrypt to char array", e);
 151                 } finally {
 152                         IOUtils.closeQuietly(writer);
 153                         IOUtils.closeQuietly(out);
 154                         IOUtils.closeQuietly(in);
 155                 }
 156         }
 157
 158         protected Provider getSecurityProvider() {
 159                 return Security.getProvider(securityProviderName);
 160         }
 161
 162         public void setLoginContextName(String loginContextName) {
 163                 this.loginContextName = loginContextName;
 164         }
 165
 166         public void setDefaultCallbackHandler(CallbackHandler defaultCallbackHandler) {
 167                 this.defaultCallbackHandler = defaultCallbackHandler;
 168         }
 169
 170         public void setCharset(String charset) {
 171                 this.charset = charset;
 172         }
 173
 174         public void setSecurityProviderName(String securityProviderName) {
 175                 this.securityProviderName = securityProviderName;
 176         }
 177
 178         @Deprecated
 179         protected static byte[] hash(char[] password, byte[] salt, Integer iterationCount) {
 180                 ByteArrayOutputStream out = null;
 181                 OutputStreamWriter writer = null;
 182                 try {
 183                         out = new ByteArrayOutputStream();
 184                         writer = new OutputStreamWriter(out, "UTF-8");
 185                         writer.write(password);
 186                         MessageDigest pwDigest = MessageDigest.getInstance("SHA-256");
 187                         pwDigest.reset();
 188                         pwDigest.update(salt);
 189                         byte[] btPass = pwDigest.digest(out.toByteArray());
 190                         for (int i = 0; i < iterationCount; i++) {
 191                                 pwDigest.reset();
 192                                 btPass = pwDigest.digest(btPass);
 193                         }
 194                         return btPass;
 195                 } catch (Exception e) {
 196                         throw new CmsException("Cannot hash", e);
 197                 } finally {
 198                         IOUtils.closeQuietly(out);
 199                         IOUtils.closeQuietly(writer);
 200                 }
 201
 202         }
 203
 204         /**
 205          * Convenience method using the underlying callback to ask for a password
 206          * (typically used when the password is not saved in the keyring)
 207          */
 208         protected char[] ask() {
 209                 PasswordCallback passwordCb = new PasswordCallback("Password", false);
 210                 Callback[] dialogCbs = new Callback[] { passwordCb };
 211                 try {
 212                         defaultCallbackHandler.handle(dialogCbs);
 213                         char[] password = passwordCb.getPassword();
 214                         return password;
 215                 } catch (Exception e) {
 216                         throw new CmsException("Cannot ask for a password", e);
 217                 }
 218
 219         }
 220
 221         class KeyringCallbackHandler implements CallbackHandler {
 222                 public void handle(Callback[] callbacks) throws IOException, UnsupportedCallbackException {
 223                         // checks
 224                         if (callbacks.length != 2)
 225                                 throw new IllegalArgumentException(
 226                                                 "Keyring required 2 and only 2 callbacks: {PasswordCallback,PBEKeySpecCallback}");
 227                         if (!(callbacks[0] instanceof PasswordCallback))
 228                                 throw new UnsupportedCallbackException(callbacks[0]);
 229                         if (!(callbacks[1] instanceof PBEKeySpecCallback))
 230                                 throw new UnsupportedCallbackException(callbacks[0]);
 231
 232                         PasswordCallback passwordCb = (PasswordCallback) callbacks[0];
 233                         PBEKeySpecCallback pbeCb = (PBEKeySpecCallback) callbacks[1];
 234
 235                         if (isSetup()) {
 236                                 Callback[] dialogCbs = new Callback[] { passwordCb };
 237                                 defaultCallbackHandler.handle(dialogCbs);
 238                         } else {// setup keyring
 239                                 TextOutputCallback textCb1 = new TextOutputCallback(TextOutputCallback.INFORMATION,
 240                                                 "Enter a master password which will protect your private data");
 241                                 TextOutputCallback textCb2 = new TextOutputCallback(TextOutputCallback.INFORMATION,
 242                                                 "(for example your credentials to third-party services)");
 243                                 TextOutputCallback textCb3 = new TextOutputCallback(TextOutputCallback.INFORMATION,
 244                                                 "Don't forget this password since the data cannot be read without it");
 245                                 PasswordCallback confirmPasswordCb = new PasswordCallback("Confirm password", false);
 246                                 // first try
 247                                 Callback[] dialogCbs = new Callback[] { textCb1, textCb2, textCb3, passwordCb, confirmPasswordCb };
 248                                 defaultCallbackHandler.handle(dialogCbs);
 249
 250                                 // if passwords different, retry (except if cancelled)
 251                                 while (passwordCb.getPassword() != null
 252                                                 && !Arrays.equals(passwordCb.getPassword(), confirmPasswordCb.getPassword())) {
 253                                         TextOutputCallback textCb = new TextOutputCallback(TextOutputCallback.ERROR,
 254                                                         "The passwords do not match");
 255                                         dialogCbs = new Callback[] { textCb, passwordCb, confirmPasswordCb };
 256                                         defaultCallbackHandler.handle(dialogCbs);
 257                                 }
 258
 259                                 if (passwordCb.getPassword() != null) {// not cancelled
 260                                         setup(passwordCb.getPassword());
 261                                 }
 262                         }
 263
 264                         if (passwordCb.getPassword() != null)
 265                                 handleKeySpecCallback(pbeCb);
 266                 }
 267
 268         }
 269 }