content: /*
   * Copyright (C) 2014 The Android Open Source Project
   * Copyright (c) 1998, 2013, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
   * particular file as subject to the "Classpath" exception as provided
   * by Oracle in the LICENSE file that accompanied this code.
   *
   * This code is distributed in the hope that it will be useful, but WITHOUT
   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   * version 2 for more details (a copy is included in the LICENSE file that
   * accompanied this code).
   *
   * You should have received a copy of the GNU General Public License version
   * 2 along with this work; if not, write to the Free Software Foundation,
   * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
   * or visit www.oracle.com if you need additional information or have any
   * questions.
   */
  
  package java.security;
  
  import java.io.*;
  import java.util.*;
  import java.security.KeyStore;
  import java.security.KeyStore.*;
  import java.security.cert.Certificate;
  import java.security.cert.CertificateException;
  
  import javax.crypto.SecretKey;
  
  import javax.security.auth.callback.*;
  
  /**
   * This class defines the <i>Service Provider Interface</i> (<b>SPI</b>)
   * for the {@code KeyStore} class.
   * All the abstract methods in this class must be implemented by each
   * cryptographic service provider who wishes to supply the implementation
   * of a keystore for a particular keystore type.
   *
   * @author Jan Luehe
   *
   *
   * @see KeyStore
   *
   * @since 1.2
   */
  
  public abstract class KeyStoreSpi {
  
      /**
       * Returns the key associated with the given alias, using the given
       * password to recover it.  The key must have been associated with
       * the alias by a call to {@code setKeyEntry},
       * or by a call to {@code setEntry} with a
       * {@code PrivateKeyEntry} or {@code SecretKeyEntry}.
       *
       * @param alias the alias name
       * @param password the password for recovering the key
       *
       * @return the requested key, or null if the given alias does not exist
       * or does not identify a key-related entry.
       *
       * @exception NoSuchAlgorithmException if the algorithm for recovering the
       * key cannot be found
       * @exception UnrecoverableKeyException if the key cannot be recovered
       * (e.g., the given password is wrong).
       */
      public abstract Key engineGetKey(String alias, char[] password)
          throws NoSuchAlgorithmException, UnrecoverableKeyException;
  
      /**
       * Returns the certificate chain associated with the given alias.
       * The certificate chain must have been associated with the alias
       * by a call to {@code setKeyEntry},
       * or by a call to {@code setEntry} with a
       * {@code PrivateKeyEntry}.
       *
       * @param alias the alias name
       *
       * @return the certificate chain (ordered with the user's certificate first
       * and the root certificate authority last), or null if the given alias
       * does not exist or does not contain a certificate chain
       */
      public abstract Certificate[] engineGetCertificateChain(String alias);
  
      /**
       * Returns the certificate associated with the given alias.
       *
       * <p> If the given alias name identifies an entry
       * created by a call to {@code setCertificateEntry},
       * or created by a call to {@code setEntry} with a
       * {@code TrustedCertificateEntry},
       * then the trusted certificate contained in that entry is returned.
       *
       * <p> If the given alias name identifies an entry
       * created by a call to {@code setKeyEntry},
       * or created by a call to {@code setEntry} with a
       * {@code PrivateKeyEntry},
       * then the first element of the certificate chain in that entry
       * (if a chain exists) is returned.
       *
       * @param alias the alias name
       *
       * @return the certificate, or null if the given alias does not exist or
       * does not contain a certificate.
       */
      public abstract Certificate engineGetCertificate(String alias);
  
      /**
       * Returns the creation date of the entry identified by the given alias.
       *
       * @param alias the alias name
       *
       * @return the creation date of this entry, or null if the given alias does
       * not exist
       */
      public abstract Date engineGetCreationDate(String alias);
  
      /**
       * Assigns the given key to the given alias, protecting it with the given
       * password.
       *
       * <p>If the given key is of type {@code java.security.PrivateKey},
       * it must be accompanied by a certificate chain certifying the
       * corresponding public key.
       *
       * <p>If the given alias already exists, the keystore information
       * associated with it is overridden by the given key (and possibly
       * certificate chain).
       *
       * @param alias the alias name
       * @param key the key to be associated with the alias
       * @param password the password to protect the key
       * @param chain the certificate chain for the corresponding public
       * key (only required if the given key is of type
       * {@code java.security.PrivateKey}).
       *
       * @exception KeyStoreException if the given key cannot be protected, or
       * this operation fails for some other reason
       */
      public abstract void engineSetKeyEntry(String alias, Key key,
                                             char[] password,
                                             Certificate[] chain)
          throws KeyStoreException;
  
      /**
       * Assigns the given key (that has already been protected) to the given
       * alias.
       *
       * <p>If the protected key is of type
       * {@code java.security.PrivateKey},
       * it must be accompanied by a certificate chain certifying the
       * corresponding public key.
       *
       * <p>If the given alias already exists, the keystore information
       * associated with it is overridden by the given key (and possibly
       * certificate chain).
       *
       * @param alias the alias name
       * @param key the key (in protected format) to be associated with the alias
       * @param chain the certificate chain for the corresponding public
       * key (only useful if the protected key is of type
       * {@code java.security.PrivateKey}).
       *
       * @exception KeyStoreException if this operation fails.
       */
      public abstract void engineSetKeyEntry(String alias, byte[] key,
                                             Certificate[] chain)
          throws KeyStoreException;
  
      /**
       * Assigns the given certificate to the given alias.
       *
       * <p> If the given alias identifies an existing entry
       * created by a call to {@code setCertificateEntry},
       * or created by a call to {@code setEntry} with a
       * {@code TrustedCertificateEntry},
       * the trusted certificate in the existing entry
       * is overridden by the given certificate.
       *
       * @param alias the alias name
       * @param cert the certificate
       *
       * @exception KeyStoreException if the given alias already exists and does
       * not identify an entry containing a trusted certificate,
       * or this operation fails for some other reason.
       */
      public abstract void engineSetCertificateEntry(String alias,
                                                     Certificate cert)
          throws KeyStoreException;
  
      /**
       * Deletes the entry identified by the given alias from this keystore.
       *
       * @param alias the alias name
       *
       * @exception KeyStoreException if the entry cannot be removed.
       */
      public abstract void engineDeleteEntry(String alias)
          throws KeyStoreException;
  
      /**
       * Lists all the alias names of this keystore.
       *
       * @return enumeration of the alias names
       */
      public abstract Enumeration<String> engineAliases();
  
      /**
       * Checks if the given alias exists in this keystore.
       *
       * @param alias the alias name
       *
       * @return true if the alias exists, false otherwise
       */
      public abstract boolean engineContainsAlias(String alias);
  
      /**
       * Retrieves the number of entries in this keystore.
       *
       * @return the number of entries in this keystore
       */
      public abstract int engineSize();
  
      /**
       * Returns true if the entry identified by the given alias
       * was created by a call to {@code setKeyEntry},
       * or created by a call to {@code setEntry} with a
       * {@code PrivateKeyEntry} or a {@code SecretKeyEntry}.
       *
       * @param alias the alias for the keystore entry to be checked
       *
       * @return true if the entry identified by the given alias is a
       * key-related, false otherwise.
       */
      public abstract boolean engineIsKeyEntry(String alias);
  
      /**
       * Returns true if the entry identified by the given alias
       * was created by a call to {@code setCertificateEntry},
       * or created by a call to {@code setEntry} with a
       * {@code TrustedCertificateEntry}.
       *
       * @param alias the alias for the keystore entry to be checked
       *
       * @return true if the entry identified by the given alias contains a
       * trusted certificate, false otherwise.
       */
      public abstract boolean engineIsCertificateEntry(String alias);
  
      /**
       * Returns the (alias) name of the first keystore entry whose certificate
       * matches the given certificate.
       *
       * <p>This method attempts to match the given certificate with each
       * keystore entry. If the entry being considered was
       * created by a call to {@code setCertificateEntry},
       * or created by a call to {@code setEntry} with a
       * {@code TrustedCertificateEntry},
       * then the given certificate is compared to that entry's certificate.
       *
       * <p> If the entry being considered was
       * created by a call to {@code setKeyEntry},
       * or created by a call to {@code setEntry} with a
       * {@code PrivateKeyEntry},
       * then the given certificate is compared to the first
       * element of that entry's certificate chain.
       *
       * @param cert the certificate to match with.
       *
       * @return the alias name of the first entry with matching certificate,
       * or null if no such entry exists in this keystore.
       */
      public abstract String engineGetCertificateAlias(Certificate cert);
  
      /**
       * Stores this keystore to the given output stream, and protects its
       * integrity with the given password.
       *
       * @param stream the output stream to which this keystore is written.
       * @param password the password to generate the keystore integrity check
       *
       * @exception IOException if there was an I/O problem with data
       * @exception NoSuchAlgorithmException if the appropriate data integrity
       * algorithm could not be found
       * @exception CertificateException if any of the certificates included in
       * the keystore data could not be stored
       */
      public abstract void engineStore(OutputStream stream, char[] password)
          throws IOException, NoSuchAlgorithmException, CertificateException;
  
      /**
       * Stores this keystore using the given
       * {@code KeyStore.LoadStoreParmeter}.
       *
       * @param param the {@code KeyStore.LoadStoreParmeter}
       *          that specifies how to store the keystore,
       *          which may be {@code null}
       *
       * @exception IllegalArgumentException if the given
       *          {@code KeyStore.LoadStoreParmeter}
       *          input is not recognized
       * @exception IOException if there was an I/O problem with data
       * @exception NoSuchAlgorithmException if the appropriate data integrity
       *          algorithm could not be found
       * @exception CertificateException if any of the certificates included in
       *          the keystore data could not be stored
       *
       * @since 1.5
       */
      public void engineStore(LoadStoreParameter param)
                  throws IOException, NoSuchAlgorithmException,
                  CertificateException {
          throw new UnsupportedOperationException();
      }
  
      /**
       * Loads the keystore from the given input stream.
       *
       * <p>A password may be given to unlock the keystore
       * (e.g. the keystore resides on a hardware token device),
       * or to check the integrity of the keystore data.
       * If a password is not given for integrity checking,
       * then integrity checking is not performed.
       *
       * @param stream the input stream from which the keystore is loaded,
       * or {@code null}
       * @param password the password used to check the integrity of
       * the keystore, the password used to unlock the keystore,
       * or {@code null}
       *
       * @exception IOException if there is an I/O or format problem with the
       * keystore data, if a password is required but not given,
       * or if the given password was incorrect. If the error is due to a
       * wrong password, the {@link Throwable#getCause cause} of the
       * {@code IOException} should be an
       * {@code UnrecoverableKeyException}
       * @exception NoSuchAlgorithmException if the algorithm used to check
       * the integrity of the keystore cannot be found
       * @exception CertificateException if any of the certificates in the
       * keystore could not be loaded
       */
      public abstract void engineLoad(InputStream stream, char[] password)
          throws IOException, NoSuchAlgorithmException, CertificateException;
  
      /**
       * Loads the keystore using the given
       * {@code KeyStore.LoadStoreParameter}.
       *
       * <p> Note that if this KeyStore has already been loaded, it is
       * reinitialized and loaded again from the given parameter.
       *
       * @param param the {@code KeyStore.LoadStoreParameter}
       *          that specifies how to load the keystore,
       *          which may be {@code null}
       *
       * @exception IllegalArgumentException if the given
       *          {@code KeyStore.LoadStoreParameter}
       *          input is not recognized
       * @exception IOException if there is an I/O or format problem with the
       *          keystore data. If the error is due to an incorrect
       *         {@code ProtectionParameter} (e.g. wrong password)
       *         the {@link Throwable#getCause cause} of the
       *         {@code IOException} should be an
       *         {@code UnrecoverableKeyException}
       * @exception NoSuchAlgorithmException if the algorithm used to check
       *          the integrity of the keystore cannot be found
       * @exception CertificateException if any of the certificates in the
       *          keystore could not be loaded
       *
       * @since 1.5
       */
      public void engineLoad(LoadStoreParameter param)
                  throws IOException, NoSuchAlgorithmException,
                  CertificateException {
  
          if (param == null) {
              engineLoad((InputStream)null, (char[])null);
              return;
          }
  
          if (param instanceof KeyStore.SimpleLoadStoreParameter) {
              ProtectionParameter protection = param.getProtectionParameter();
              char[] password;
              if (protection instanceof PasswordProtection) {
                  password = ((PasswordProtection)protection).getPassword();
              } else if (protection instanceof CallbackHandlerProtection) {
                  CallbackHandler handler =
                      ((CallbackHandlerProtection)protection).getCallbackHandler();
                  PasswordCallback callback =
                      new PasswordCallback("Password: ", false);
                  try {
                      handler.handle(new Callback[] {callback});
                  } catch (UnsupportedCallbackException e) {
                      throw new NoSuchAlgorithmException
                          ("Could not obtain password", e);
                  }
                  password = callback.getPassword();
                  callback.clearPassword();
                  if (password == null) {
                      throw new NoSuchAlgorithmException
                          ("No password provided");
                  }
              } else {
                  throw new NoSuchAlgorithmException("ProtectionParameter must"
                      + " be PasswordProtection or CallbackHandlerProtection");
              }
              engineLoad(null, password);
              return;
          }
  
          throw new UnsupportedOperationException();
      }
  
      /**
       * Gets a {@code KeyStore.Entry} for the specified alias
       * with the specified protection parameter.
       *
       * @param alias get the {@code KeyStore.Entry} for this alias
       * @param protParam the {@code ProtectionParameter}
       *          used to protect the {@code Entry},
       *          which may be {@code null}
       *
       * @return the {@code KeyStore.Entry} for the specified alias,
       *          or {@code null} if there is no such entry
       *
       * @exception KeyStoreException if the operation failed
       * @exception NoSuchAlgorithmException if the algorithm for recovering the
       *          entry cannot be found
       * @exception UnrecoverableEntryException if the specified
       *          {@code protParam} were insufficient or invalid
       * @exception UnrecoverableKeyException if the entry is a
       *          {@code PrivateKeyEntry} or {@code SecretKeyEntry}
       *          and the specified {@code protParam} does not contain
       *          the information needed to recover the key (e.g. wrong password)
       *
       * @since 1.5
       */
      public Entry engineGetEntry(String alias,
                          ProtectionParameter protParam)
                  throws KeyStoreException, NoSuchAlgorithmException,
                  UnrecoverableEntryException {
  
          if (!engineContainsAlias(alias)) {
              return null;
          }
  
          if (protParam == null) {
              if (engineIsCertificateEntry(alias)) {
                  return new TrustedCertificateEntry
                                  (engineGetCertificate(alias));
              // Android-removed: Allow access to entries with no password.
              // } else {
              //    throw new UnrecoverableKeyException
              //            ("requested entry requires a password");
              }
          }
  
          // Android-changed: Add protParam == null to allow access to entries with no password.
          if ((protParam == null) || protParam instanceof PasswordProtection) {
              if (engineIsCertificateEntry(alias)) {
                  throw new UnsupportedOperationException
                      ("trusted certificate entries are not password-protected");
              } else if (engineIsKeyEntry(alias)) {
                  // Android-changed: Allow access to entries with no password.
                  // KeyStore.PasswordProtection pp =
                  //         (KeyStore.PasswordProtection)protParam;
                  // char[] password = pp.getPassword();
                  char[] password = null;
                  if (protParam != null) {
                      PasswordProtection pp =
                          (PasswordProtection)protParam;
                      password = pp.getPassword();
                  }
                  Key key = engineGetKey(alias, password);
                  if (key instanceof PrivateKey) {
                      Certificate[] chain = engineGetCertificateChain(alias);
                      return new PrivateKeyEntry((PrivateKey)key, chain);
                  } else if (key instanceof SecretKey) {
                      return new SecretKeyEntry((SecretKey)key);
                  }
              }
          }
  
          throw new UnsupportedOperationException();
      }
  
      /**
       * Saves a {@code KeyStore.Entry} under the specified alias.
       * The specified protection parameter is used to protect the
       * {@code Entry}.
       *
       * <p> If an entry already exists for the specified alias,
       * it is overridden.
       *
       * @param alias save the {@code KeyStore.Entry} under this alias
       * @param entry the {@code Entry} to save
       * @param protParam the {@code ProtectionParameter}
       *          used to protect the {@code Entry},
       *          which may be {@code null}
       *
       * @exception KeyStoreException if this operation fails
       *
       * @since 1.5
       */
      public void engineSetEntry(String alias, Entry entry,
                          ProtectionParameter protParam)
                  throws KeyStoreException {
  
          // get password
          if (protParam != null &&
              !(protParam instanceof PasswordProtection)) {
              throw new KeyStoreException("unsupported protection parameter");
          }
          PasswordProtection pProtect = null;
          if (protParam != null) {
              pProtect = (PasswordProtection)protParam;
          }
  
          // BEGIN Android-changed: Allow access to entries with no password.
          char[] password = (pProtect == null) ? null : pProtect.getPassword();
          // set entry
          if (entry instanceof TrustedCertificateEntry) {
              TrustedCertificateEntry tce =
                      (TrustedCertificateEntry)entry;
              engineSetCertificateEntry(alias, tce.getTrustedCertificate());
              return;
          } else if (entry instanceof PrivateKeyEntry) {
              engineSetKeyEntry
                  (alias,
                  ((PrivateKeyEntry)entry).getPrivateKey(),
                  password,
                  ((PrivateKeyEntry)entry).getCertificateChain());
              return;
          } else if (entry instanceof SecretKeyEntry) {
              engineSetKeyEntry
                  (alias,
                  ((SecretKeyEntry)entry).getSecretKey(),
                  password,
                  (Certificate[])null);
              return;
          }
          // END Android-changed: Allow access to entries with no password.
  
          throw new KeyStoreException
                  ("unsupported entry type: " + entry.getClass().getName());
      }
  
      /**
       * Determines if the keystore {@code Entry} for the specified
       * {@code alias} is an instance or subclass of the specified
       * {@code entryClass}.
       *
       * @param alias the alias name
       * @param entryClass the entry class
       *
       * @return true if the keystore {@code Entry} for the specified
       *          {@code alias} is an instance or subclass of the
       *          specified {@code entryClass}, false otherwise
       *
       * @since 1.5
       */
      public boolean
          engineEntryInstanceOf(String alias,
                                Class<? extends Entry> entryClass)
      {
          if (entryClass == TrustedCertificateEntry.class) {
              return engineIsCertificateEntry(alias);
          }
          if (entryClass == PrivateKeyEntry.class) {
              return engineIsKeyEntry(alias) &&
                          engineGetCertificate(alias) != null;
          }
          if (entryClass == SecretKeyEntry.class) {
              return engineIsKeyEntry(alias) &&
                          engineGetCertificate(alias) == null;
          }
          return false;
      }
  }
  