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Java example source code file (Subject.java)

This example Java source code file (Subject.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

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Java - Java tags/keywords

accesscontrolcontext, authpermission, classset, iterator, linkedlist, nullpointerexception, object, principal, principal_set, priv_credential_set, reflection, secureset, security, set, string, subject, text, util

The Subject.java Java example source code

/*
 * 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 javax.security.auth;

import java.util.*;
import java.io.*;
import java.lang.reflect.*;
import java.text.MessageFormat;
import java.security.AccessController;
import java.security.AccessControlContext;
import java.security.DomainCombiner;
import java.security.Permission;
import java.security.PermissionCollection;
import java.security.Principal;
import java.security.PrivilegedAction;
import java.security.PrivilegedExceptionAction;
import java.security.PrivilegedActionException;
import java.security.ProtectionDomain;
import sun.security.util.ResourcesMgr;

/**
 * <p> A {@code Subject} represents a grouping of related information
 * for a single entity, such as a person.
 * Such information includes the Subject's identities as well as
 * its security-related attributes
 * (passwords and cryptographic keys, for example).
 *
 * <p> Subjects may potentially have multiple identities.
 * Each identity is represented as a {@code Principal}
 * within the {@code Subject}.  Principals simply bind names to a
 * {@code Subject}.  For example, a {@code Subject} that happens
 * to be a person, Alice, might have two Principals:
 * one which binds "Alice Bar", the name on her driver license,
 * to the {@code Subject}, and another which binds,
 * "999-99-9999", the number on her student identification card,
 * to the {@code Subject}.  Both Principals refer to the same
 * {@code Subject} even though each has a different name.
 *
 * <p> A {@code Subject} may also own security-related attributes,
 * which are referred to as credentials.
 * Sensitive credentials that require special protection, such as
 * private cryptographic keys, are stored within a private credential
 * {@code Set}.  Credentials intended to be shared, such as
 * public key certificates or Kerberos server tickets are stored
 * within a public credential {@code Set}.  Different permissions
 * are required to access and modify the different credential Sets.
 *
 * <p> To retrieve all the Principals associated with a {@code Subject},
 * invoke the {@code getPrincipals} method.  To retrieve
 * all the public or private credentials belonging to a {@code Subject},
 * invoke the {@code getPublicCredentials} method or
 * {@code getPrivateCredentials} method, respectively.
 * To modify the returned {@code Set} of Principals and credentials,
 * use the methods defined in the {@code Set} class.
 * For example:
 * <pre>
 *      Subject subject;
 *      Principal principal;
 *      Object credential;
 *
 *      // add a Principal and credential to the Subject
 *      subject.getPrincipals().add(principal);
 *      subject.getPublicCredentials().add(credential);
 * </pre>
 *
 * <p> This {@code Subject} class implements {@code Serializable}.
 * While the Principals associated with the {@code Subject} are serialized,
 * the credentials associated with the {@code Subject} are not.
 * Note that the {@code java.security.Principal} class
 * does not implement {@code Serializable}.  Therefore all concrete
 * {@code Principal} implementations associated with Subjects
 * must implement {@code Serializable}.
 *
 * @see java.security.Principal
 * @see java.security.DomainCombiner
 */
public final class Subject implements java.io.Serializable {

    private static final long serialVersionUID = -8308522755600156056L;

    /**
     * A {@code Set} that provides a view of all of this
     * Subject's Principals
     *
     * <p>
     *
     * @serial Each element in this set is a
     *          {@code java.security.Principal}.
     *          The set is a {@code Subject.SecureSet}.
     */
    Set<Principal> principals;

    /**
     * Sets that provide a view of all of this
     * Subject's Credentials
     */
    transient Set<Object> pubCredentials;
    transient Set<Object> privCredentials;

    /**
     * Whether this Subject is read-only
     *
     * @serial
     */
    private volatile boolean readOnly = false;

    private static final int PRINCIPAL_SET = 1;
    private static final int PUB_CREDENTIAL_SET = 2;
    private static final int PRIV_CREDENTIAL_SET = 3;

    private static final ProtectionDomain[] NULL_PD_ARRAY
        = new ProtectionDomain[0];

    /**
     * Create an instance of a {@code Subject}
     * with an empty {@code Set} of Principals and empty
     * Sets of public and private credentials.
     *
     * <p> The newly constructed Sets check whether this {@code Subject}
     * has been set read-only before permitting subsequent modifications.
     * The newly created Sets also prevent illegal modifications
     * by ensuring that callers have sufficient permissions.
     *
     * <p> To modify the Principals Set, the caller must have
     * {@code AuthPermission("modifyPrincipals")}.
     * To modify the public credential Set, the caller must have
     * {@code AuthPermission("modifyPublicCredentials")}.
     * To modify the private credential Set, the caller must have
     * {@code AuthPermission("modifyPrivateCredentials")}.
     */
    public Subject() {

        this.principals = Collections.synchronizedSet
                        (new SecureSet<Principal>(this, PRINCIPAL_SET));
        this.pubCredentials = Collections.synchronizedSet
                        (new SecureSet<Object>(this, PUB_CREDENTIAL_SET));
        this.privCredentials = Collections.synchronizedSet
                        (new SecureSet<Object>(this, PRIV_CREDENTIAL_SET));
    }

    /**
     * Create an instance of a {@code Subject} with
     * Principals and credentials.
     *
     * <p> The Principals and credentials from the specified Sets
     * are copied into newly constructed Sets.
     * These newly created Sets check whether this {@code Subject}
     * has been set read-only before permitting subsequent modifications.
     * The newly created Sets also prevent illegal modifications
     * by ensuring that callers have sufficient permissions.
     *
     * <p> To modify the Principals Set, the caller must have
     * {@code AuthPermission("modifyPrincipals")}.
     * To modify the public credential Set, the caller must have
     * {@code AuthPermission("modifyPublicCredentials")}.
     * To modify the private credential Set, the caller must have
     * {@code AuthPermission("modifyPrivateCredentials")}.
     * <p>
     *
     * @param readOnly true if the {@code Subject} is to be read-only,
     *          and false otherwise. <p>
     *
     * @param principals the {@code Set} of Principals
     *          to be associated with this {@code Subject}. <p>
     *
     * @param pubCredentials the {@code Set} of public credentials
     *          to be associated with this {@code Subject}. <p>
     *
     * @param privCredentials the {@code Set} of private credentials
     *          to be associated with this {@code Subject}.
     *
     * @exception NullPointerException if the specified
     *          {@code principals}, {@code pubCredentials},
     *          or {@code privCredentials} are {@code null}.
     */
    public Subject(boolean readOnly, Set<? extends Principal> principals,
                   Set<?> pubCredentials, Set privCredentials)
    {

        if (principals == null ||
            pubCredentials == null ||
            privCredentials == null)
            throw new NullPointerException
                (ResourcesMgr.getString("invalid.null.input.s."));

        this.principals = Collections.synchronizedSet(new SecureSet<Principal>
                                (this, PRINCIPAL_SET, principals));
        this.pubCredentials = Collections.synchronizedSet(new SecureSet<Object>
                                (this, PUB_CREDENTIAL_SET, pubCredentials));
        this.privCredentials = Collections.synchronizedSet(new SecureSet<Object>
                                (this, PRIV_CREDENTIAL_SET, privCredentials));
        this.readOnly = readOnly;
    }

    /**
     * Set this {@code Subject} to be read-only.
     *
     * <p> Modifications (additions and removals) to this Subject's
     * {@code Principal} {@code Set} and
     * credential Sets will be disallowed.
     * The {@code destroy} operation on this Subject's credentials will
     * still be permitted.
     *
     * <p> Subsequent attempts to modify the Subject's {@code Principal}
     * and credential Sets will result in an
     * {@code IllegalStateException} being thrown.
     * Also, once a {@code Subject} is read-only,
     * it can not be reset to being writable again.
     *
     * <p>
     *
     * @exception SecurityException if the caller does not have permission
     *          to set this {@code Subject} to be read-only.
     */
    public void setReadOnly() {
        java.lang.SecurityManager sm = System.getSecurityManager();
        if (sm != null) {
            sm.checkPermission(AuthPermissionHolder.SET_READ_ONLY_PERMISSION);
        }

        this.readOnly = true;
    }

    /**
     * Query whether this {@code Subject} is read-only.
     *
     * <p>
     *
     * @return true if this {@code Subject} is read-only, false otherwise.
     */
    public boolean isReadOnly() {
        return this.readOnly;
    }

    /**
     * Get the {@code Subject} associated with the provided
     * {@code AccessControlContext}.
     *
     * <p> The {@code AccessControlContext} may contain many
     * Subjects (from nested {@code doAs} calls).
     * In this situation, the most recent {@code Subject} associated
     * with the {@code AccessControlContext} is returned.
     *
     * <p>
     *
     * @param  acc the {@code AccessControlContext} from which to retrieve
     *          the {@code Subject}.
     *
     * @return  the {@code Subject} associated with the provided
     *          {@code AccessControlContext}, or {@code null}
     *          if no {@code Subject} is associated
     *          with the provided {@code AccessControlContext}.
     *
     * @exception SecurityException if the caller does not have permission
     *          to get the {@code Subject}. <p>
     *
     * @exception NullPointerException if the provided
     *          {@code AccessControlContext} is {@code null}.
     */
    public static Subject getSubject(final AccessControlContext acc) {

        java.lang.SecurityManager sm = System.getSecurityManager();
        if (sm != null) {
            sm.checkPermission(AuthPermissionHolder.GET_SUBJECT_PERMISSION);
        }

        if (acc == null) {
            throw new NullPointerException(ResourcesMgr.getString
                ("invalid.null.AccessControlContext.provided"));
        }

        // return the Subject from the DomainCombiner of the provided context
        return AccessController.doPrivileged
            (new java.security.PrivilegedAction<Subject>() {
            public Subject run() {
                DomainCombiner dc = acc.getDomainCombiner();
                if (!(dc instanceof SubjectDomainCombiner))
                    return null;
                SubjectDomainCombiner sdc = (SubjectDomainCombiner)dc;
                return sdc.getSubject();
            }
        });
    }

    /**
     * Perform work as a particular {@code Subject}.
     *
     * <p> This method first retrieves the current Thread's
     * {@code AccessControlContext} via
     * {@code AccessController.getContext},
     * and then instantiates a new {@code AccessControlContext}
     * using the retrieved context along with a new
     * {@code SubjectDomainCombiner} (constructed using
     * the provided {@code Subject}).
     * Finally, this method invokes {@code AccessController.doPrivileged},
     * passing it the provided {@code PrivilegedAction},
     * as well as the newly constructed {@code AccessControlContext}.
     *
     * <p>
     *
     * @param subject the {@code Subject} that the specified
     *                  {@code action} will run as.  This parameter
     *                  may be {@code null}. <p>
     *
     * @param <T> the type of the value returned by the PrivilegedAction's
     *                  {@code run} method.
     *
     * @param action the code to be run as the specified
     *                  {@code Subject}. <p>
     *
     * @return the value returned by the PrivilegedAction's
     *                  {@code run} method.
     *
     * @exception NullPointerException if the {@code PrivilegedAction}
     *                  is {@code null}. <p>
     *
     * @exception SecurityException if the caller does not have permission
     *                  to invoke this method.
     */
    public static <T> T doAs(final Subject subject,
                        final java.security.PrivilegedAction<T> action) {

        java.lang.SecurityManager sm = System.getSecurityManager();
        if (sm != null) {
            sm.checkPermission(AuthPermissionHolder.DO_AS_PERMISSION);
        }
        if (action == null)
            throw new NullPointerException
                (ResourcesMgr.getString("invalid.null.action.provided"));

        // set up the new Subject-based AccessControlContext
        // for doPrivileged
        final AccessControlContext currentAcc = AccessController.getContext();

        // call doPrivileged and push this new context on the stack
        return java.security.AccessController.doPrivileged
                                        (action,
                                        createContext(subject, currentAcc));
    }

    /**
     * Perform work as a particular {@code Subject}.
     *
     * <p> This method first retrieves the current Thread's
     * {@code AccessControlContext} via
     * {@code AccessController.getContext},
     * and then instantiates a new {@code AccessControlContext}
     * using the retrieved context along with a new
     * {@code SubjectDomainCombiner} (constructed using
     * the provided {@code Subject}).
     * Finally, this method invokes {@code AccessController.doPrivileged},
     * passing it the provided {@code PrivilegedExceptionAction},
     * as well as the newly constructed {@code AccessControlContext}.
     *
     * <p>
     *
     * @param subject the {@code Subject} that the specified
     *                  {@code action} will run as.  This parameter
     *                  may be {@code null}. <p>
     *
     * @param <T> the type of the value returned by the
     *                  PrivilegedExceptionAction's {@code run} method.
     *
     * @param action the code to be run as the specified
     *                  {@code Subject}. <p>
     *
     * @return the value returned by the
     *                  PrivilegedExceptionAction's {@code run} method.
     *
     * @exception PrivilegedActionException if the
     *                  {@code PrivilegedExceptionAction.run}
     *                  method throws a checked exception. <p>
     *
     * @exception NullPointerException if the specified
     *                  {@code PrivilegedExceptionAction} is
     *                  {@code null}. <p>
     *
     * @exception SecurityException if the caller does not have permission
     *                  to invoke this method.
     */
    public static <T> T doAs(final Subject subject,
                        final java.security.PrivilegedExceptionAction<T> action)
                        throws java.security.PrivilegedActionException {

        java.lang.SecurityManager sm = System.getSecurityManager();
        if (sm != null) {
            sm.checkPermission(AuthPermissionHolder.DO_AS_PERMISSION);
        }

        if (action == null)
            throw new NullPointerException
                (ResourcesMgr.getString("invalid.null.action.provided"));

        // set up the new Subject-based AccessControlContext for doPrivileged
        final AccessControlContext currentAcc = AccessController.getContext();

        // call doPrivileged and push this new context on the stack
        return java.security.AccessController.doPrivileged
                                        (action,
                                        createContext(subject, currentAcc));
    }

    /**
     * Perform privileged work as a particular {@code Subject}.
     *
     * <p> This method behaves exactly as {@code Subject.doAs},
     * except that instead of retrieving the current Thread's
     * {@code AccessControlContext}, it uses the provided
     * {@code AccessControlContext}.  If the provided
     * {@code AccessControlContext} is {@code null},
     * this method instantiates a new {@code AccessControlContext}
     * with an empty collection of ProtectionDomains.
     *
     * <p>
     *
     * @param subject the {@code Subject} that the specified
     *                  {@code action} will run as.  This parameter
     *                  may be {@code null}. <p>
     *
     * @param <T> the type of the value returned by the PrivilegedAction's
     *                  {@code run} method.
     *
     * @param action the code to be run as the specified
     *                  {@code Subject}. <p>
     *
     * @param acc the {@code AccessControlContext} to be tied to the
     *                  specified <i>subject and action. 

* * @return the value returned by the PrivilegedAction's * {@code run} method. * * @exception NullPointerException if the {@code PrivilegedAction} * is {@code null}. <p> * * @exception SecurityException if the caller does not have permission * to invoke this method. */ public static <T> T doAsPrivileged(final Subject subject, final java.security.PrivilegedAction<T> action, final java.security.AccessControlContext acc) { java.lang.SecurityManager sm = System.getSecurityManager(); if (sm != null) { sm.checkPermission(AuthPermissionHolder.DO_AS_PRIVILEGED_PERMISSION); } if (action == null) throw new NullPointerException (ResourcesMgr.getString("invalid.null.action.provided")); // set up the new Subject-based AccessControlContext // for doPrivileged final AccessControlContext callerAcc = (acc == null ? new AccessControlContext(NULL_PD_ARRAY) : acc); // call doPrivileged and push this new context on the stack return java.security.AccessController.doPrivileged (action, createContext(subject, callerAcc)); } /** * Perform privileged work as a particular {@code Subject}. * * <p> This method behaves exactly as {@code Subject.doAs}, * except that instead of retrieving the current Thread's * {@code AccessControlContext}, it uses the provided * {@code AccessControlContext}. If the provided * {@code AccessControlContext} is {@code null}, * this method instantiates a new {@code AccessControlContext} * with an empty collection of ProtectionDomains. * * <p> * * @param subject the {@code Subject} that the specified * {@code action} will run as. This parameter * may be {@code null}. <p> * * @param <T> the type of the value returned by the * PrivilegedExceptionAction's {@code run} method. * * @param action the code to be run as the specified * {@code Subject}. <p> * * @param acc the {@code AccessControlContext} to be tied to the * specified <i>subject and action.

* * @return the value returned by the * PrivilegedExceptionAction's {@code run} method. * * @exception PrivilegedActionException if the * {@code PrivilegedExceptionAction.run} * method throws a checked exception. <p> * * @exception NullPointerException if the specified * {@code PrivilegedExceptionAction} is * {@code null}. <p> * * @exception SecurityException if the caller does not have permission * to invoke this method. */ public static <T> T doAsPrivileged(final Subject subject, final java.security.PrivilegedExceptionAction<T> action, final java.security.AccessControlContext acc) throws java.security.PrivilegedActionException { java.lang.SecurityManager sm = System.getSecurityManager(); if (sm != null) { sm.checkPermission(AuthPermissionHolder.DO_AS_PRIVILEGED_PERMISSION); } if (action == null) throw new NullPointerException (ResourcesMgr.getString("invalid.null.action.provided")); // set up the new Subject-based AccessControlContext for doPrivileged final AccessControlContext callerAcc = (acc == null ? new AccessControlContext(NULL_PD_ARRAY) : acc); // call doPrivileged and push this new context on the stack return java.security.AccessController.doPrivileged (action, createContext(subject, callerAcc)); } private static AccessControlContext createContext(final Subject subject, final AccessControlContext acc) { return java.security.AccessController.doPrivileged (new java.security.PrivilegedAction<AccessControlContext>() { public AccessControlContext run() { if (subject == null) return new AccessControlContext(acc, null); else return new AccessControlContext (acc, new SubjectDomainCombiner(subject)); } }); } /** * Return the {@code Set} of Principals associated with this * {@code Subject}. Each {@code Principal} represents * an identity for this {@code Subject}. * * <p> The returned {@code Set} is backed by this Subject's * internal {@code Principal} {@code Set}. Any modification * to the returned {@code Set} affects the internal * {@code Principal} {@code Set} as well. * * <p> * * @return The {@code Set} of Principals associated with this * {@code Subject}. */ public Set<Principal> getPrincipals() { // always return an empty Set instead of null // so LoginModules can add to the Set if necessary return principals; } /** * Return a {@code Set} of Principals associated with this * {@code Subject} that are instances or subclasses of the specified * {@code Class}. * * <p> The returned {@code Set} is not backed by this Subject's * internal {@code Principal} {@code Set}. A new * {@code Set} is created and returned for each method invocation. * Modifications to the returned {@code Set} * will not affect the internal {@code Principal} {@code Set}. * * <p> * * @param <T> the type of the class modeled by {@code c} * * @param c the returned {@code Set} of Principals will all be * instances of this class. * * @return a {@code Set} of Principals that are instances of the * specified {@code Class}. * * @exception NullPointerException if the specified {@code Class} * is {@code null}. */ public <T extends Principal> Set getPrincipals(Class c) { if (c == null) throw new NullPointerException (ResourcesMgr.getString("invalid.null.Class.provided")); // always return an empty Set instead of null // so LoginModules can add to the Set if necessary return new ClassSet<T>(PRINCIPAL_SET, c); } /** * Return the {@code Set} of public credentials held by this * {@code Subject}. * * <p> The returned {@code Set} is backed by this Subject's * internal public Credential {@code Set}. Any modification * to the returned {@code Set} affects the internal public * Credential {@code Set} as well. * * <p> * * @return A {@code Set} of public credentials held by this * {@code Subject}. */ public Set<Object> getPublicCredentials() { // always return an empty Set instead of null // so LoginModules can add to the Set if necessary return pubCredentials; } /** * Return the {@code Set} of private credentials held by this * {@code Subject}. * * <p> The returned {@code Set} is backed by this Subject's * internal private Credential {@code Set}. Any modification * to the returned {@code Set} affects the internal private * Credential {@code Set} as well. * * <p> A caller requires permissions to access the Credentials * in the returned {@code Set}, or to modify the * {@code Set} itself. A {@code SecurityException} * is thrown if the caller does not have the proper permissions. * * <p> While iterating through the {@code Set}, * a {@code SecurityException} is thrown * if the caller does not have permission to access a * particular Credential. The {@code Iterator} * is nevertheless advanced to next element in the {@code Set}. * * <p> * * @return A {@code Set} of private credentials held by this * {@code Subject}. */ public Set<Object> getPrivateCredentials() { // XXX // we do not need a security check for // AuthPermission(getPrivateCredentials) // because we already restrict access to private credentials // via the PrivateCredentialPermission. all the extra AuthPermission // would do is protect the set operations themselves // (like size()), which don't seem security-sensitive. // always return an empty Set instead of null // so LoginModules can add to the Set if necessary return privCredentials; } /** * Return a {@code Set} of public credentials associated with this * {@code Subject} that are instances or subclasses of the specified * {@code Class}. * * <p> The returned {@code Set} is not backed by this Subject's * internal public Credential {@code Set}. A new * {@code Set} is created and returned for each method invocation. * Modifications to the returned {@code Set} * will not affect the internal public Credential {@code Set}. * * <p> * * @param <T> the type of the class modeled by {@code c} * * @param c the returned {@code Set} of public credentials will all be * instances of this class. * * @return a {@code Set} of public credentials that are instances * of the specified {@code Class}. * * @exception NullPointerException if the specified {@code Class} * is {@code null}. */ public <T> Set getPublicCredentials(Class c) { if (c == null) throw new NullPointerException (ResourcesMgr.getString("invalid.null.Class.provided")); // always return an empty Set instead of null // so LoginModules can add to the Set if necessary return new ClassSet<T>(PUB_CREDENTIAL_SET, c); } /** * Return a {@code Set} of private credentials associated with this * {@code Subject} that are instances or subclasses of the specified * {@code Class}. * * <p> The caller must have permission to access all of the * requested Credentials, or a {@code SecurityException} * will be thrown. * * <p> The returned {@code Set} is not backed by this Subject's * internal private Credential {@code Set}. A new * {@code Set} is created and returned for each method invocation. * Modifications to the returned {@code Set} * will not affect the internal private Credential {@code Set}. * * <p> * * @param <T> the type of the class modeled by {@code c} * * @param c the returned {@code Set} of private credentials will all be * instances of this class. * * @return a {@code Set} of private credentials that are instances * of the specified {@code Class}. * * @exception NullPointerException if the specified {@code Class} * is {@code null}. */ public <T> Set getPrivateCredentials(Class c) { // XXX // we do not need a security check for // AuthPermission(getPrivateCredentials) // because we already restrict access to private credentials // via the PrivateCredentialPermission. all the extra AuthPermission // would do is protect the set operations themselves // (like size()), which don't seem security-sensitive. if (c == null) throw new NullPointerException (ResourcesMgr.getString("invalid.null.Class.provided")); // always return an empty Set instead of null // so LoginModules can add to the Set if necessary return new ClassSet<T>(PRIV_CREDENTIAL_SET, c); } /** * Compares the specified Object with this {@code Subject} * for equality. Returns true if the given object is also a Subject * and the two {@code Subject} instances are equivalent. * More formally, two {@code Subject} instances are * equal if their {@code Principal} and {@code Credential} * Sets are equal. * * <p> * * @param o Object to be compared for equality with this * {@code Subject}. * * @return true if the specified Object is equal to this * {@code Subject}. * * @exception SecurityException if the caller does not have permission * to access the private credentials for this {@code Subject}, * or if the caller does not have permission to access the * private credentials for the provided {@code Subject}. */ public boolean equals(Object o) { if (o == null) return false; if (this == o) return true; if (o instanceof Subject) { final Subject that = (Subject)o; // check the principal and credential sets Set<Principal> thatPrincipals; synchronized(that.principals) { // avoid deadlock from dual locks thatPrincipals = new HashSet<Principal>(that.principals); } if (!principals.equals(thatPrincipals)) { return false; } Set<Object> thatPubCredentials; synchronized(that.pubCredentials) { // avoid deadlock from dual locks thatPubCredentials = new HashSet<Object>(that.pubCredentials); } if (!pubCredentials.equals(thatPubCredentials)) { return false; } Set<Object> thatPrivCredentials; synchronized(that.privCredentials) { // avoid deadlock from dual locks thatPrivCredentials = new HashSet<Object>(that.privCredentials); } if (!privCredentials.equals(thatPrivCredentials)) { return false; } return true; } return false; } /** * Return the String representation of this {@code Subject}. * * <p> * * @return the String representation of this {@code Subject}. */ public String toString() { return toString(true); } /** * package private convenience method to print out the Subject * without firing off a security check when trying to access * the Private Credentials */ String toString(boolean includePrivateCredentials) { String s = ResourcesMgr.getString("Subject."); String suffix = ""; synchronized(principals) { Iterator<Principal> pI = principals.iterator(); while (pI.hasNext()) { Principal p = pI.next(); suffix = suffix + ResourcesMgr.getString(".Principal.") + p.toString() + ResourcesMgr.getString("NEWLINE"); } } synchronized(pubCredentials) { Iterator<Object> pI = pubCredentials.iterator(); while (pI.hasNext()) { Object o = pI.next(); suffix = suffix + ResourcesMgr.getString(".Public.Credential.") + o.toString() + ResourcesMgr.getString("NEWLINE"); } } if (includePrivateCredentials) { synchronized(privCredentials) { Iterator<Object> pI = privCredentials.iterator(); while (pI.hasNext()) { try { Object o = pI.next(); suffix += ResourcesMgr.getString (".Private.Credential.") + o.toString() + ResourcesMgr.getString("NEWLINE"); } catch (SecurityException se) { suffix += ResourcesMgr.getString (".Private.Credential.inaccessible."); break; } } } } return s + suffix; } /** * Returns a hashcode for this {@code Subject}. * * <p> * * @return a hashcode for this {@code Subject}. * * @exception SecurityException if the caller does not have permission * to access this Subject's private credentials. */ public int hashCode() { /** * The hashcode is derived exclusive or-ing the * hashcodes of this Subject's Principals and credentials. * * If a particular credential was destroyed * ({@code credential.hashCode()} throws an * {@code IllegalStateException}), * the hashcode for that credential is derived via: * {@code credential.getClass().toString().hashCode()}. */ int hashCode = 0; synchronized(principals) { Iterator<Principal> pIterator = principals.iterator(); while (pIterator.hasNext()) { Principal p = pIterator.next(); hashCode ^= p.hashCode(); } } synchronized(pubCredentials) { Iterator<Object> pubCIterator = pubCredentials.iterator(); while (pubCIterator.hasNext()) { hashCode ^= getCredHashCode(pubCIterator.next()); } } return hashCode; } /** * get a credential's hashcode */ private int getCredHashCode(Object o) { try { return o.hashCode(); } catch (IllegalStateException ise) { return o.getClass().toString().hashCode(); } } /** * Writes this object out to a stream (i.e., serializes it). */ private void writeObject(java.io.ObjectOutputStream oos) throws java.io.IOException { synchronized(principals) { oos.defaultWriteObject(); } } /** * Reads this object from a stream (i.e., deserializes it) */ private void readObject(java.io.ObjectInputStream s) throws java.io.IOException, ClassNotFoundException { s.defaultReadObject(); // Rewrap the principals into a SecureSet principals = Collections.synchronizedSet(new SecureSet<Principal> (this, PRINCIPAL_SET, principals)); // The Credential {@code Set} is not serialized, but we do not // want the default deserialization routine to set it to null. this.pubCredentials = Collections.synchronizedSet (new SecureSet<Object>(this, PUB_CREDENTIAL_SET)); this.privCredentials = Collections.synchronizedSet (new SecureSet<Object>(this, PRIV_CREDENTIAL_SET)); } /** * Prevent modifications unless caller has permission. * * @serial include */ private static class SecureSet<E> extends AbstractSet<E> implements java.io.Serializable { private static final long serialVersionUID = 7911754171111800359L; /** * @serialField this$0 Subject The outer Subject instance. * @serialField elements LinkedList The elements in this set. */ private static final ObjectStreamField[] serialPersistentFields = { new ObjectStreamField("this$0", Subject.class), new ObjectStreamField("elements", LinkedList.class), new ObjectStreamField("which", int.class) }; Subject subject; LinkedList<E> elements; /** * @serial An integer identifying the type of objects contained * in this set. If {@code which == 1}, * this is a Principal set and all the elements are * of type {@code java.security.Principal}. * If {@code which == 2}, this is a public credential * set and all the elements are of type {@code Object}. * If {@code which == 3}, this is a private credential * set and all the elements are of type {@code Object}. */ private int which; SecureSet(Subject subject, int which) { this.subject = subject; this.which = which; this.elements = new LinkedList<E>(); } SecureSet(Subject subject, int which, Set<? extends E> set) { this.subject = subject; this.which = which; this.elements = new LinkedList<E>(set); } public int size() { return elements.size(); } public Iterator<E> iterator() { final LinkedList<E> list = elements; return new Iterator<E>() { ListIterator<E> i = list.listIterator(0); public boolean hasNext() {return i.hasNext();} public E next() { if (which != Subject.PRIV_CREDENTIAL_SET) { return i.next(); } SecurityManager sm = System.getSecurityManager(); if (sm != null) { try { sm.checkPermission(new PrivateCredentialPermission (list.get(i.nextIndex()).getClass().getName(), subject.getPrincipals())); } catch (SecurityException se) { i.next(); throw (se); } } return i.next(); } public void remove() { if (subject.isReadOnly()) { throw new IllegalStateException(ResourcesMgr.getString ("Subject.is.read.only")); } java.lang.SecurityManager sm = System.getSecurityManager(); if (sm != null) { switch (which) { case Subject.PRINCIPAL_SET: sm.checkPermission(AuthPermissionHolder.MODIFY_PRINCIPALS_PERMISSION); break; case Subject.PUB_CREDENTIAL_SET: sm.checkPermission(AuthPermissionHolder.MODIFY_PUBLIC_CREDENTIALS_PERMISSION); break; default: sm.checkPermission(AuthPermissionHolder.MODIFY_PRIVATE_CREDENTIALS_PERMISSION); break; } } i.remove(); } }; } public boolean add(E o) { if (subject.isReadOnly()) { throw new IllegalStateException (ResourcesMgr.getString("Subject.is.read.only")); } java.lang.SecurityManager sm = System.getSecurityManager(); if (sm != null) { switch (which) { case Subject.PRINCIPAL_SET: sm.checkPermission(AuthPermissionHolder.MODIFY_PRINCIPALS_PERMISSION); break; case Subject.PUB_CREDENTIAL_SET: sm.checkPermission(AuthPermissionHolder.MODIFY_PUBLIC_CREDENTIALS_PERMISSION); break; default: sm.checkPermission(AuthPermissionHolder.MODIFY_PRIVATE_CREDENTIALS_PERMISSION); break; } } switch (which) { case Subject.PRINCIPAL_SET: if (!(o instanceof Principal)) { throw new SecurityException(ResourcesMgr.getString ("attempting.to.add.an.object.which.is.not.an.instance.of.java.security.Principal.to.a.Subject.s.Principal.Set")); } break; default: // ok to add Objects of any kind to credential sets break; } // check for duplicates if (!elements.contains(o)) return elements.add(o); else return false; } public boolean remove(Object o) { final Iterator<E> e = iterator(); while (e.hasNext()) { E next; if (which != Subject.PRIV_CREDENTIAL_SET) { next = e.next(); } else { next = java.security.AccessController.doPrivileged (new java.security.PrivilegedAction<E>() { public E run() { return e.next(); } }); } if (next == null) { if (o == null) { e.remove(); return true; } } else if (next.equals(o)) { e.remove(); return true; } } return false; } public boolean contains(Object o) { final Iterator<E> e = iterator(); while (e.hasNext()) { E next; if (which != Subject.PRIV_CREDENTIAL_SET) { next = e.next(); } else { // For private credentials: // If the caller does not have read permission for // for o.getClass(), we throw a SecurityException. // Otherwise we check the private cred set to see whether // it contains the Object SecurityManager sm = System.getSecurityManager(); if (sm != null) { sm.checkPermission(new PrivateCredentialPermission (o.getClass().getName(), subject.getPrincipals())); } next = java.security.AccessController.doPrivileged (new java.security.PrivilegedAction<E>() { public E run() { return e.next(); } }); } if (next == null) { if (o == null) { return true; } } else if (next.equals(o)) { return true; } } return false; } public boolean removeAll(Collection<?> c) { Objects.requireNonNull(c); boolean modified = false; final Iterator<E> e = iterator(); while (e.hasNext()) { E next; if (which != Subject.PRIV_CREDENTIAL_SET) { next = e.next(); } else { next = java.security.AccessController.doPrivileged (new java.security.PrivilegedAction<E>() { public E run() { return e.next(); } }); } Iterator<?> ce = c.iterator(); while (ce.hasNext()) { Object o = ce.next(); if (next == null) { if (o == null) { e.remove(); modified = true; break; } } else if (next.equals(o)) { e.remove(); modified = true; break; } } } return modified; } public boolean retainAll(Collection<?> c) { Objects.requireNonNull(c); boolean modified = false; boolean retain = false; final Iterator<E> e = iterator(); while (e.hasNext()) { retain = false; E next; if (which != Subject.PRIV_CREDENTIAL_SET) { next = e.next(); } else { next = java.security.AccessController.doPrivileged (new java.security.PrivilegedAction<E>() { public E run() { return e.next(); } }); } Iterator<?> ce = c.iterator(); while (ce.hasNext()) { Object o = ce.next(); if (next == null) { if (o == null) { retain = true; break; } } else if (next.equals(o)) { retain = true; break; } } if (!retain) { e.remove(); retain = false; modified = true; } } return modified; } public void clear() { final Iterator<E> e = iterator(); while (e.hasNext()) { E next; if (which != Subject.PRIV_CREDENTIAL_SET) { next = e.next(); } else { next = java.security.AccessController.doPrivileged (new java.security.PrivilegedAction<E>() { public E run() { return e.next(); } }); } e.remove(); } } /** * Writes this object out to a stream (i.e., serializes it). * * <p> * * @serialData If this is a private credential set, * a security check is performed to ensure that * the caller has permission to access each credential * in the set. If the security check passes, * the set is serialized. */ private void writeObject(java.io.ObjectOutputStream oos) throws java.io.IOException { if (which == Subject.PRIV_CREDENTIAL_SET) { // check permissions before serializing Iterator<E> i = iterator(); while (i.hasNext()) { i.next(); } } ObjectOutputStream.PutField fields = oos.putFields(); fields.put("this$0", subject); fields.put("elements", elements); fields.put("which", which); oos.writeFields(); } @SuppressWarnings("unchecked") private void readObject(ObjectInputStream ois) throws IOException, ClassNotFoundException { ObjectInputStream.GetField fields = ois.readFields(); subject = (Subject) fields.get("this$0", null); which = fields.get("which", 0); LinkedList<E> tmp = (LinkedList) fields.get("elements", null); if (tmp.getClass() != LinkedList.class) { elements = new LinkedList<E>(tmp); } else { elements = tmp; } } } /** * This class implements a {@code Set} which returns only * members that are an instance of a specified Class. */ private class ClassSet<T> extends AbstractSet { private int which; private Class<T> c; private Set<T> set; ClassSet(int which, Class<T> c) { this.which = which; this.c = c; set = new HashSet<T>(); switch (which) { case Subject.PRINCIPAL_SET: synchronized(principals) { populateSet(); } break; case Subject.PUB_CREDENTIAL_SET: synchronized(pubCredentials) { populateSet(); } break; default: synchronized(privCredentials) { populateSet(); } break; } } @SuppressWarnings("unchecked") /*To suppress warning from line 1374*/ private void populateSet() { final Iterator<?> iterator; switch(which) { case Subject.PRINCIPAL_SET: iterator = Subject.this.principals.iterator(); break; case Subject.PUB_CREDENTIAL_SET: iterator = Subject.this.pubCredentials.iterator(); break; default: iterator = Subject.this.privCredentials.iterator(); break; } // Check whether the caller has permisson to get // credentials of Class c while (iterator.hasNext()) { Object next; if (which == Subject.PRIV_CREDENTIAL_SET) { next = java.security.AccessController.doPrivileged (new java.security.PrivilegedAction<Object>() { public Object run() { return iterator.next(); } }); } else { next = iterator.next(); } if (c.isAssignableFrom(next.getClass())) { if (which != Subject.PRIV_CREDENTIAL_SET) { set.add((T)next); } else { // Check permission for private creds SecurityManager sm = System.getSecurityManager(); if (sm != null) { sm.checkPermission(new PrivateCredentialPermission (next.getClass().getName(), Subject.this.getPrincipals())); } set.add((T)next); } } } } public int size() { return set.size(); } public Iterator<T> iterator() { return set.iterator(); } public boolean add(T o) { if (!o.getClass().isAssignableFrom(c)) { MessageFormat form = new MessageFormat(ResourcesMgr.getString ("attempting.to.add.an.object.which.is.not.an.instance.of.class")); Object[] source = {c.toString()}; throw new SecurityException(form.format(source)); } return set.add(o); } } static class AuthPermissionHolder { static final AuthPermission DO_AS_PERMISSION = new AuthPermission("doAs"); static final AuthPermission DO_AS_PRIVILEGED_PERMISSION = new AuthPermission("doAsPrivileged"); static final AuthPermission SET_READ_ONLY_PERMISSION = new AuthPermission("setReadOnly"); static final AuthPermission GET_SUBJECT_PERMISSION = new AuthPermission("getSubject"); static final AuthPermission MODIFY_PRINCIPALS_PERMISSION = new AuthPermission("modifyPrincipals"); static final AuthPermission MODIFY_PUBLIC_CREDENTIALS_PERMISSION = new AuthPermission("modifyPublicCredentials"); static final AuthPermission MODIFY_PRIVATE_CREDENTIALS_PERMISSION = new AuthPermission("modifyPrivateCredentials"); } }

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