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.Provider;
  29 import java.security.Security;
  30 import java.util.Arrays;
  31 import java.util.Iterator;
  32
  33 import javax.crypto.SecretKey;
  34 import javax.security.auth.Subject;
  35 import javax.security.auth.callback.Callback;
  36 import javax.security.auth.callback.CallbackHandler;
  37 import javax.security.auth.callback.PasswordCallback;
  38 import javax.security.auth.callback.TextOutputCallback;
  39 import javax.security.auth.callback.UnsupportedCallbackException;
  40 import javax.security.auth.login.LoginContext;
  41 import javax.security.auth.login.LoginException;
  42
  43 import org.apache.commons.io.IOUtils;
  44 import org.argeo.cms.CmsException;
  45 import org.argeo.node.NodeConstants;
  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(char[] password) {
  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() || password!=null) {// not initialized
  90                         CallbackHandler callbackHandler = password == null ? new KeyringCallbackHandler()
  91                                         : new PasswordProvidedCallBackHandler(password);
  92                         ClassLoader currentContextClassLoader = Thread.currentThread().getContextClassLoader();
  93                         Thread.currentThread().setContextClassLoader(getClass().getClassLoader());
  94                         try {
  95                                 LoginContext loginContext = new LoginContext(NodeConstants.LOGIN_CONTEXT_KEYRING, subject,
  96                                                 callbackHandler);
  97                                 loginContext.login();
  98                                 // FIXME will login even if password is wrong
  99                                 iterator = subject.getPrivateCredentials(SecretKey.class).iterator();
 100                                 return iterator.next();
 101                         } catch (LoginException e) {
 102                                 throw new CmsException("Keyring login failed", e);
 103                         } finally {
 104                                 Thread.currentThread().setContextClassLoader(currentContextClassLoader);
 105                         }
 106
 107                 } else {
 108                         SecretKey secretKey = iterator.next();
 109                         if (iterator.hasNext())
 110                                 throw new CmsException("More than one secret key in private credentials");
 111                         return secretKey;
 112                 }
 113         }
 114
 115         public InputStream getAsStream(String path) {
 116                 return decrypt(path);
 117         }
 118
 119         public void set(String path, InputStream in) {
 120                 encrypt(path, in);
 121         }
 122
 123         public char[] getAsChars(String path) {
 124                 // InputStream in = getAsStream(path);
 125                 // CharArrayWriter writer = null;
 126                 // Reader reader = null;
 127                 try (InputStream in = getAsStream(path);
 128                                 CharArrayWriter writer = new CharArrayWriter();
 129                                 Reader reader = new InputStreamReader(in, charset);) {
 130                         IOUtils.copy(reader, writer);
 131                         return writer.toCharArray();
 132                 } catch (IOException e) {
 133                         throw new CmsException("Cannot decrypt to char array", e);
 134                 } finally {
 135                         // IOUtils.closeQuietly(reader);
 136                         // IOUtils.closeQuietly(in);
 137                         // IOUtils.closeQuietly(writer);
 138                 }
 139         }
 140
 141         public void set(String path, char[] arr) {
 142                 // ByteArrayOutputStream out = new ByteArrayOutputStream();
 143                 // ByteArrayInputStream in = null;
 144                 // Writer writer = null;
 145                 try (ByteArrayOutputStream out = new ByteArrayOutputStream();
 146                                 Writer writer = new OutputStreamWriter(out, charset);) {
 147                         // writer = new OutputStreamWriter(out, charset);
 148                         writer.write(arr);
 149                         writer.flush();
 150                         // in = new ByteArrayInputStream(out.toByteArray());
 151                         try (ByteArrayInputStream in = new ByteArrayInputStream(out.toByteArray());) {
 152                                 set(path, in);
 153                         }
 154                 } catch (IOException e) {
 155                         throw new CmsException("Cannot encrypt to char array", e);
 156                 } finally {
 157                         // IOUtils.closeQuietly(writer);
 158                         // IOUtils.closeQuietly(out);
 159                         // IOUtils.closeQuietly(in);
 160                 }
 161         }
 162
 163         public void unlock(char[] password) {
 164                 if (!isSetup())
 165                         setup(password);
 166                 SecretKey secretKey = getSecretKey(password);
 167                 if (secretKey == null)
 168                         throw new CmsException("Could not unlock keyring");
 169         }
 170
 171         protected Provider getSecurityProvider() {
 172                 return Security.getProvider(securityProviderName);
 173         }
 174
 175         public void setDefaultCallbackHandler(CallbackHandler defaultCallbackHandler) {
 176                 this.defaultCallbackHandler = defaultCallbackHandler;
 177         }
 178
 179         public void setCharset(String charset) {
 180                 this.charset = charset;
 181         }
 182
 183         public void setSecurityProviderName(String securityProviderName) {
 184                 this.securityProviderName = securityProviderName;
 185         }
 186
 187         // @Deprecated
 188         // protected static byte[] hash(char[] password, byte[] salt, Integer
 189         // iterationCount) {
 190         // ByteArrayOutputStream out = null;
 191         // OutputStreamWriter writer = null;
 192         // try {
 193         // out = new ByteArrayOutputStream();
 194         // writer = new OutputStreamWriter(out, "UTF-8");
 195         // writer.write(password);
 196         // MessageDigest pwDigest = MessageDigest.getInstance("SHA-256");
 197         // pwDigest.reset();
 198         // pwDigest.update(salt);
 199         // byte[] btPass = pwDigest.digest(out.toByteArray());
 200         // for (int i = 0; i < iterationCount; i++) {
 201         // pwDigest.reset();
 202         // btPass = pwDigest.digest(btPass);
 203         // }
 204         // return btPass;
 205         // } catch (Exception e) {
 206         // throw new CmsException("Cannot hash", e);
 207         // } finally {
 208         // IOUtils.closeQuietly(out);
 209         // IOUtils.closeQuietly(writer);
 210         // }
 211         //
 212         // }
 213
 214         /**
 215          * Convenience method using the underlying callback to ask for a password
 216          * (typically used when the password is not saved in the keyring)
 217          */
 218         protected char[] ask() {
 219                 PasswordCallback passwordCb = new PasswordCallback("Password", false);
 220                 Callback[] dialogCbs = new Callback[] { passwordCb };
 221                 try {
 222                         defaultCallbackHandler.handle(dialogCbs);
 223                         char[] password = passwordCb.getPassword();
 224                         return password;
 225                 } catch (Exception e) {
 226                         throw new CmsException("Cannot ask for a password", e);
 227                 }
 228
 229         }
 230
 231         class KeyringCallbackHandler implements CallbackHandler {
 232                 public void handle(Callback[] callbacks) throws IOException, UnsupportedCallbackException {
 233                         // checks
 234                         if (callbacks.length != 2)
 235                                 throw new IllegalArgumentException(
 236                                                 "Keyring requires 2 and only 2 callbacks: {PasswordCallback,PBEKeySpecCallback}");
 237                         if (!(callbacks[0] instanceof PasswordCallback))
 238                                 throw new UnsupportedCallbackException(callbacks[0]);
 239                         if (!(callbacks[1] instanceof PBEKeySpecCallback))
 240                                 throw new UnsupportedCallbackException(callbacks[0]);
 241
 242                         PasswordCallback passwordCb = (PasswordCallback) callbacks[0];
 243                         PBEKeySpecCallback pbeCb = (PBEKeySpecCallback) callbacks[1];
 244
 245                         if (isSetup()) {
 246                                 Callback[] dialogCbs = new Callback[] { passwordCb };
 247                                 defaultCallbackHandler.handle(dialogCbs);
 248                         } else {// setup keyring
 249                                 TextOutputCallback textCb1 = new TextOutputCallback(TextOutputCallback.INFORMATION,
 250                                                 "Enter a master password which will protect your private data");
 251                                 TextOutputCallback textCb2 = new TextOutputCallback(TextOutputCallback.INFORMATION,
 252                                                 "(for example your credentials to third-party services)");
 253                                 TextOutputCallback textCb3 = new TextOutputCallback(TextOutputCallback.INFORMATION,
 254                                                 "Don't forget this password since the data cannot be read without it");
 255                                 PasswordCallback confirmPasswordCb = new PasswordCallback("Confirm password", false);
 256                                 // first try
 257                                 Callback[] dialogCbs = new Callback[] { textCb1, textCb2, textCb3, passwordCb, confirmPasswordCb };
 258                                 defaultCallbackHandler.handle(dialogCbs);
 259
 260                                 // if passwords different, retry (except if cancelled)
 261                                 while (passwordCb.getPassword() != null
 262                                                 && !Arrays.equals(passwordCb.getPassword(), confirmPasswordCb.getPassword())) {
 263                                         TextOutputCallback textCb = new TextOutputCallback(TextOutputCallback.ERROR,
 264                                                         "The passwords do not match");
 265                                         dialogCbs = new Callback[] { textCb, passwordCb, confirmPasswordCb };
 266                                         defaultCallbackHandler.handle(dialogCbs);
 267                                 }
 268
 269                                 if (passwordCb.getPassword() != null) {// not cancelled
 270                                         setup(passwordCb.getPassword());
 271                                 }
 272                         }
 273
 274                         if (passwordCb.getPassword() != null)
 275                                 handleKeySpecCallback(pbeCb);
 276                 }
 277
 278         }
 279
 280         class PasswordProvidedCallBackHandler implements CallbackHandler {
 281                 private final char[] password;
 282
 283                 public PasswordProvidedCallBackHandler(char[] password) {
 284                         this.password = password;
 285                 }
 286
 287                 @Override
 288                 public void handle(Callback[] callbacks) throws IOException, UnsupportedCallbackException {
 289                         // checks
 290                         if (callbacks.length != 2)
 291                                 throw new IllegalArgumentException(
 292                                                 "Keyring requires 2 and only 2 callbacks: {PasswordCallback,PBEKeySpecCallback}");
 293                         if (!(callbacks[0] instanceof PasswordCallback))
 294                                 throw new UnsupportedCallbackException(callbacks[0]);
 295                         if (!(callbacks[1] instanceof PBEKeySpecCallback))
 296                                 throw new UnsupportedCallbackException(callbacks[0]);
 297
 298                         PasswordCallback passwordCb = (PasswordCallback) callbacks[0];
 299                         passwordCb.setPassword(password);
 300                         PBEKeySpecCallback pbeCb = (PBEKeySpecCallback) callbacks[1];
 301                         handleKeySpecCallback(pbeCb);
 302                 }
 303
 304         }
 305 }