/*
    * Copyright (c) 1999, 2011, 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
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   * questions.
   */
  
  package javax.security.auth;
  
  import java.util.*;
  import java.text.MessageFormat;
  import java.security.Permission;
  import java.security.PermissionCollection;
  import java.security.Principal;
  import sun.security.util.ResourcesMgr;
  
  /**
   * This class is used to protect access to private Credentials
   * belonging to a particular <code>Subject</code>.  The <code>Subject</code>
   * is represented by a Set of Principals.
   *
   * <p> The target name of this <code>Permission</code> specifies
   * a Credential class name, and a Set of Principals.
   * The only valid value for this Permission's actions is, "read".
   * The target name must abide by the following syntax:
   *
   * <pre>
   *      CredentialClass {PrincipalClass "PrincipalName"}*
   * </pre>
   *
   * For example, the following permission grants access to the
   * com.sun.PrivateCredential owned by Subjects which have
   * a com.sun.Principal with the name, "duke".  Note that although
   * this example, as well as all the examples below, do not contain
   * Codebase, SignedBy, or Principal information in the grant statement
   * (for simplicity reasons), actual policy configurations should
   * specify that information when appropriate.
   *
   * <pre>
   *
   *    grant {
   *      permission javax.security.auth.PrivateCredentialPermission
   *              "com.sun.PrivateCredential com.sun.Principal \"duke\"",
   *              "read";
   *    };
   * </pre>
   *
   * If CredentialClass is "*", then access is granted to
   * all private Credentials belonging to the specified
   * <code>Subject</code>.
   * If "PrincipalName" is "*", then access is granted to the
   * specified Credential owned by any <code>Subject</code> that has the
   * specified <code>Principal</code> (the actual PrincipalName doesn't matter).
   * For example, the following grants access to the
   * a.b.Credential owned by any <code>Subject</code> that has
   * an a.b.Principal.
   *
   * <pre>
   *    grant {
   *      permission javax.security.auth.PrivateCredentialPermission
   *              "a.b.Credential a.b.Principal "*"",
   *              "read";
   *    };
   * </pre>
   *
   * If both the PrincipalClass and "PrincipalName" are "*",
   * then access is granted to the specified Credential owned by
   * any <code>Subject</code>.
   *
   * <p> In addition, the PrincipalClass/PrincipalName pairing may be repeated:
   *
   * <pre>
   *    grant {
   *      permission javax.security.auth.PrivateCredentialPermission
   *              "a.b.Credential a.b.Principal "duke" c.d.Principal "dukette"",
   *              "read";
   *    };
   * </pre>
   *
   * The above grants access to the private Credential, "a.b.Credential",
   * belonging to a <code>Subject</code> with at least two associated Principals:
  * "a.b.Principal" with the name, "duke", and "c.d.Principal", with the name,
  * "dukette".
  *
  */
 public final class PrivateCredentialPermission extends Permission {
 
     private static final long serialVersionUID = 5284372143517237068L;
 
     private static final CredOwner[] EMPTY_PRINCIPALS = new CredOwner[0];
 
     /**
      * @serial
      */
     private String credentialClass;
 
     /**
      * @serial The Principals associated with this permission.
      *          The set contains elements of type,
      *          <code>PrivateCredentialPermission.CredOwner</code>.
      */
     private Set principals;  // ignored - kept around for compatibility
     private transient CredOwner[] credOwners;
 
     /**
      * @serial
      */
     private boolean testing = false;
 
     /**
      * Create a new <code>PrivateCredentialPermission</code>
      * with the specified <code>credentialClass</code> and Principals.
      */
     PrivateCredentialPermission(String credentialClass,
                         Set<Principal> principals) {
 
         super(credentialClass);
         this.credentialClass = credentialClass;
 
         synchronized(principals) {
             if (principals.size() == 0) {
                 this.credOwners = EMPTY_PRINCIPALS;
             } else {
                 this.credOwners = new CredOwner[principals.size()];
                 int index = 0;
                 Iterator<Principal> i = principals.iterator();
                 while (i.hasNext()) {
                     Principal p = i.next();
                     this.credOwners[index++] = new CredOwner
                                                 (p.getClass().getName(),
                                                 p.getName());
                 }
             }
         }
     }
 
     /**
      * Creates a new <code>PrivateCredentialPermission</code>
      * with the specified <code>name</code>.  The <code>name</code>
      * specifies both a Credential class and a <code>Principal</code> Set.
      *
      * <p>
      *
      * @param name the name specifying the Credential class and
      *          <code>Principal</code> Set. <p>
      *
      * @param actions the actions specifying that the Credential can be read.
      *
      * @throws IllegalArgumentException if <code>name</code> does not conform
      *          to the correct syntax or if <code>actions</code> is not "read".
      */
     public PrivateCredentialPermission(String name, String actions) {
         super(name);
 
         if (!"read".equalsIgnoreCase(actions))
             throw new IllegalArgumentException
                 (ResourcesMgr.getString("actions.can.only.be.read."));
         init(name);
     }
 
     /**
      * Returns the Class name of the Credential associated with this
      * <code>PrivateCredentialPermission</code>.
      *
      * <p>
      *
      * @return the Class name of the Credential associated with this
      *          <code>PrivateCredentialPermission</code>.
      */
     public String getCredentialClass() {
         return credentialClass;
     }
 
     /**
      * Returns the <code>Principal</code> classes and names
      * associated with this <code>PrivateCredentialPermission</code>.
      * The information is returned as a two-dimensional array (array[x][y]).
      * The 'x' value corresponds to the number of <code>Principal</code>
      * class and name pairs.  When (y==0), it corresponds to
      * the <code>Principal</code> class value, and when (y==1),
      * it corresponds to the <code>Principal</code> name value.
      * For example, array[0][0] corresponds to the class name of
      * the first <code>Principal</code> in the array.  array[0][1]
      * corresponds to the <code>Principal</code> name of the
      * first <code>Principal</code> in the array.
      *
      * <p>
      *
      * @return the <code>Principal</code> class and names associated
      *          with this <code>PrivateCredentialPermission</code>.
      */
     public String[][] getPrincipals() {
 
         if (credOwners == null || credOwners.length == 0) {
             return new String[0][0];
         }
 
         String[][] pArray = new String[credOwners.length][2];
         for (int i = 0; i < credOwners.length; i++) {
             pArray[i][0] = credOwners[i].principalClass;
             pArray[i][1] = credOwners[i].principalName;
         }
         return pArray;
     }
 
     /**
      * Checks if this <code>PrivateCredentialPermission</code> implies
      * the specified <code>Permission</code>.
      *
      * <p>
      *
      * This method returns true if:
      * <p><ul>
      * <li> <i>p</i> is an instanceof PrivateCredentialPermission and <p>
      * <li> the target name for <i>p</i> is implied by this object's
      *          target name.  For example:
      * <pre>
      *  [* P1 "duke"] implies [a.b.Credential P1 "duke"].
      *  [C1 P1 "duke"] implies [C1 P1 "duke" P2 "dukette"].
      *  [C1 P2 "dukette"] implies [C1 P1 "duke" P2 "dukette"].
      * </pre>
      * </ul>
      *
      * <p>
      *
      * @param p the <code>Permission</code> to check against.
      *
      * @return true if this <code>PrivateCredentialPermission</code> implies
      * the specified <code>Permission</code>, false if not.
      */
     public boolean implies(Permission p) {
 
         if (p == null || !(p instanceof PrivateCredentialPermission))
             return false;
 
         PrivateCredentialPermission that = (PrivateCredentialPermission)p;
 
         if (!impliesCredentialClass(credentialClass, that.credentialClass))
             return false;
 
         return impliesPrincipalSet(credOwners, that.credOwners);
     }
 
     /**
      * Checks two <code>PrivateCredentialPermission</code> objects for
      * equality.  Checks that <i>obj</i> is a
      * <code>PrivateCredentialPermission</code>,
      * and has the same credential class as this object,
      * as well as the same Principals as this object.
      * The order of the Principals in the respective Permission's
      * target names is not relevant.
      *
      * <p>
      *
      * @param obj the object we are testing for equality with this object.
      *
      * @return true if obj is a <code>PrivateCredentialPermission</code>,
      *          has the same credential class as this object,
      *          and has the same Principals as this object.
      */
     public boolean equals(Object obj) {
         if (obj == this)
             return true;
 
         if (! (obj instanceof PrivateCredentialPermission))
             return false;
 
         PrivateCredentialPermission that = (PrivateCredentialPermission)obj;
 
         return (this.implies(that) && that.implies(this));
     }
 
     /**
      * Returns the hash code value for this object.
      *
      * @return a hash code value for this object.
      */
     public int hashCode() {
         return this.credentialClass.hashCode();
     }
 
     /**
      * Returns the "canonical string representation" of the actions.
      * This method always returns the String, "read".
      *
      * <p>
      *
      * @return the actions (always returns "read").
      */
     public String getActions() {
         return "read";
     }
 
     /**
      * Return a homogeneous collection of PrivateCredentialPermissions
      * in a <code>PermissionCollection</code>.
      * No such <code>PermissionCollection</code> is defined,
      * so this method always returns <code>null</code>.
      *
      * <p>
      *
      * @return null in all cases.
      */
     public PermissionCollection newPermissionCollection() {
         return null;
     }
 
     private void init(String name) {
 
         if (name == null || name.trim().length() == 0) {
             throw new IllegalArgumentException("invalid empty name");
         }
 
         ArrayList<CredOwner> pList = new ArrayList<>();
         StringTokenizer tokenizer = new StringTokenizer(name, " ", true);
         String principalClass = null;
         String principalName = null;
 
         if (testing)
             System.out.println("whole name = " + name);
 
         // get the Credential Class
         credentialClass = tokenizer.nextToken();
         if (testing)
             System.out.println("Credential Class = " + credentialClass);
 
         if (tokenizer.hasMoreTokens() == false) {
             MessageFormat form = new MessageFormat(ResourcesMgr.getString
                 ("permission.name.name.syntax.invalid."));
             Object[] source = {name};
             throw new IllegalArgumentException
                 (form.format(source) + ResourcesMgr.getString
                         ("Credential.Class.not.followed.by.a.Principal.Class.and.Name"));
         }
 
         while (tokenizer.hasMoreTokens()) {
 
             // skip delimiter
             tokenizer.nextToken();
 
             // get the Principal Class
             principalClass = tokenizer.nextToken();
             if (testing)
                 System.out.println("    Principal Class = " + principalClass);
 
             if (tokenizer.hasMoreTokens() == false) {
                 MessageFormat form = new MessageFormat(ResourcesMgr.getString
                         ("permission.name.name.syntax.invalid."));
                 Object[] source = {name};
                 throw new IllegalArgumentException
                         (form.format(source) + ResourcesMgr.getString
                         ("Principal.Class.not.followed.by.a.Principal.Name"));
             }
 
             // skip delimiter
             tokenizer.nextToken();
 
             // get the Principal Name
             principalName = tokenizer.nextToken();
 
             if (!principalName.startsWith("\"")) {
                 MessageFormat form = new MessageFormat(ResourcesMgr.getString
                         ("permission.name.name.syntax.invalid."));
                 Object[] source = {name};
                 throw new IllegalArgumentException
                         (form.format(source) + ResourcesMgr.getString
                         ("Principal.Name.must.be.surrounded.by.quotes"));
             }
 
             if (!principalName.endsWith("\"")) {
 
                 // we have a name with spaces in it --
                 // keep parsing until we find the end quote,
                 // and keep the spaces in the name
 
                 while (tokenizer.hasMoreTokens()) {
                     principalName = principalName + tokenizer.nextToken();
                     if (principalName.endsWith("\""))
                         break;
                 }
 
                 if (!principalName.endsWith("\"")) {
                     MessageFormat form = new MessageFormat
                         (ResourcesMgr.getString
                         ("permission.name.name.syntax.invalid."));
                     Object[] source = {name};
                     throw new IllegalArgumentException
                         (form.format(source) + ResourcesMgr.getString
                                 ("Principal.Name.missing.end.quote"));
                 }
             }
 
             if (testing)
                 System.out.println("\tprincipalName = '" + principalName + "'");
 
             principalName = principalName.substring
                                         (1, principalName.length() - 1);
 
             if (principalClass.equals("*") &&
                 !principalName.equals("*")) {
                     throw new IllegalArgumentException(ResourcesMgr.getString
                         ("PrivateCredentialPermission.Principal.Class.can.not.be.a.wildcard.value.if.Principal.Name.is.not.a.wildcard.value"));
             }
 
             if (testing)
                 System.out.println("\tprincipalName = '" + principalName + "'");
 
             pList.add(new CredOwner(principalClass, principalName));
         }
 
         this.credOwners = new CredOwner[pList.size()];
         pList.toArray(this.credOwners);
     }
 
     private boolean impliesCredentialClass(String thisC, String thatC) {
 
         // this should never happen
         if (thisC == null || thatC == null)
             return false;
 
         if (testing)
             System.out.println("credential class comparison: " +
                                 thisC + "/" + thatC);
 
         if (thisC.equals("*"))
             return true;
 
         /**
          * XXX let's not enable this for now --
          *      if people want it, we'll enable it later
          */
         /*
         if (thisC.endsWith("*")) {
             String cClass = thisC.substring(0, thisC.length() - 2);
             return thatC.startsWith(cClass);
         }
         */
 
         return thisC.equals(thatC);
     }
 
     private boolean impliesPrincipalSet(CredOwner[] thisP, CredOwner[] thatP) {
 
         // this should never happen
         if (thisP == null || thatP == null)
             return false;
 
         if (thatP.length == 0)
             return true;
 
         if (thisP.length == 0)
             return false;
 
         for (int i = 0; i < thisP.length; i++) {
             boolean foundMatch = false;
             for (int j = 0; j < thatP.length; j++) {
                 if (thisP[i].implies(thatP[j])) {
                     foundMatch = true;
                     break;
                 }
             }
             if (!foundMatch) {
                 return false;
             }
         }
         return true;
     }
 
     /**
      * Reads this object from a stream (i.e., deserializes it)
      */
     private void readObject(java.io.ObjectInputStream s) throws
                                         java.io.IOException,
                                         ClassNotFoundException {
 
         s.defaultReadObject();
 
         // perform new initialization from the permission name
 
         if (getName().indexOf(" ") == -1 && getName().indexOf("\"") == -1) {
 
             // name only has a credential class specified
             credentialClass = getName();
             credOwners = EMPTY_PRINCIPALS;
 
         } else {
 
             // perform regular initialization
             init(getName());
         }
     }
 
     /**
      * @serial include
      */
     static class CredOwner implements java.io.Serializable {
 
         private static final long serialVersionUID = -5607449830436408266L;
 
         /**
          * @serial
          */
         String principalClass;
         /**
          * @serial
          */
         String principalName;
 
         CredOwner(String principalClass, String principalName) {
             this.principalClass = principalClass;
             this.principalName = principalName;
         }
 
         public boolean implies(Object obj) {
             if (obj == null || !(obj instanceof CredOwner))
                 return false;
 
             CredOwner that = (CredOwner)obj;
 
             if (principalClass.equals("*") ||
                 principalClass.equals(that.principalClass)) {
 
                 if (principalName.equals("*") ||
                     principalName.equals(that.principalName)) {
                     return true;
                 }
             }
 
             /**
              * XXX no code yet to support a.b.*
              */
 
             return false;
         }
 
         public String toString() {
             MessageFormat form = new MessageFormat(ResourcesMgr.getString
                 ("CredOwner.Principal.Class.class.Principal.Name.name"));
             Object[] source = {principalClass, principalName};
             return (form.format(source));
         }
     }
 }