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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * 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
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 *
 * 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).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
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package sun.security.provider;

import java.net.URL;
import java.util.*;
import java.security.CodeSource;
import java.security.Principal;
import java.security.cert.Certificate;
import java.lang.reflect.Constructor;

import javax.security.auth.Subject;
import sun.security.provider.PolicyParser.PrincipalEntry;
import sun.security.util.ResourcesMgr;

 This SubjectCodeSource class contains
a URL, signer certificates, and either a Subject
(that represents the Subject in the current
AccessControlContext), or a linked list of Principals
(that represent a "subject" in a Policy).
/**
 * <p> This <code>SubjectCodeSource</code> class contains
 * a <code>URL</code>, signer certificates, and either a <code>Subject</code>
 * (that represents the <code>Subject</code> in the current
 * <code>AccessControlContext</code>), or a linked list of Principals
 * (that represent a "subject" in a <code>Policy</code>).
 *
 */
class SubjectCodeSource extends CodeSource implements java.io.Serializable {

    private static final long serialVersionUID = 6039418085604715275L;

    private Subject subject;
    private LinkedList<PrincipalEntry> principals;
    private static final Class<?>[] PARAMS = { String.class };
    private static final sun.security.util.Debug debug =
        sun.security.util.Debug.getInstance("auth", "\t[Auth Access]");
    private ClassLoader sysClassLoader;

    
Creates a new SubjectCodeSource
with the given Subject, principals, URL,
and signers (Certificates).  The Subject
represents the Subject associated with the current
AccessControlContext.
The Principals are given as a LinkedList
of PolicyParser.PrincipalEntry objects.
Typically either a Subject will be provided,
or a list of principals will be provided
(not both).

Params:
subject – the Subject associated with this
                 SubjectCodeSource 
url – the URL associated with this
                 SubjectCodeSource 
certs – the signers associated with this
                 SubjectCodeSource 
/**
     * Creates a new <code>SubjectCodeSource</code>
     * with the given <code>Subject</code>, principals, <code>URL</code>,
     * and signers (Certificates).  The <code>Subject</code>
     * represents the <code>Subject</code> associated with the current
     * <code>AccessControlContext</code>.
     * The Principals are given as a <code>LinkedList</code>
     * of <code>PolicyParser.PrincipalEntry</code> objects.
     * Typically either a <code>Subject</code> will be provided,
     * or a list of <code>principals</code> will be provided
     * (not both).
     *
     * <p>
     *
     * @param subject the <code>Subject</code> associated with this
     *                  <code>SubjectCodeSource</code> <p>
     *
     * @param url the <code>URL</code> associated with this
     *                  <code>SubjectCodeSource</code> <p>
     *
     * @param certs the signers associated with this
     *                  <code>SubjectCodeSource</code> <p>
     */
    SubjectCodeSource(Subject subject,
        LinkedList<PrincipalEntry> principals,
        URL url, Certificate[] certs) {

        super(url, certs);
        this.subject = subject;
        this.principals = (principals == null ?
                new LinkedList<PrincipalEntry>() :
                new LinkedList<PrincipalEntry>(principals));
        sysClassLoader = java.security.AccessController.doPrivileged
        (new java.security.PrivilegedAction<ClassLoader>() {
            public ClassLoader run() {
                    return ClassLoader.getSystemClassLoader();
            }
        });
    }

    
Get the Principals associated with this SubjectCodeSource.
The Principals are retrieved as a LinkedList
of PolicyParser.PrincipalEntry objects.

Returns:
the Principals associated with this
         SubjectCodeSource as a LinkedList
         of PolicyParser.PrincipalEntry objects./**
     * Get the Principals associated with this <code>SubjectCodeSource</code>.
     * The Principals are retrieved as a <code>LinkedList</code>
     * of <code>PolicyParser.PrincipalEntry</code> objects.
     *
     * <p>
     *
     * @return the Principals associated with this
     *          <code>SubjectCodeSource</code> as a <code>LinkedList</code>
     *          of <code>PolicyParser.PrincipalEntry</code> objects.
     */
    LinkedList<PrincipalEntry> getPrincipals() {
        return principals;
    }

    
Get the Subject associated with this
SubjectCodeSource.  The Subject
represents the Subject associated with the
current AccessControlContext.

Returns:
the Subject associated with this
         SubjectCodeSource./**
     * Get the <code>Subject</code> associated with this
     * <code>SubjectCodeSource</code>.  The <code>Subject</code>
     * represents the <code>Subject</code> associated with the
     * current <code>AccessControlContext</code>.
     *
     * <p>
     *
     * @return the <code>Subject</code> associated with this
     *          <code>SubjectCodeSource</code>.
     */
    Subject getSubject() {
        return subject;
    }

    
Returns true if this SubjectCodeSource object "implies"
the specified CodeSource.
More specifically, this method makes the following checks.
If any fail, it returns false.  If they all succeed, it returns true.


 The provided codesource must not be null.
 codesource must be an instance of SubjectCodeSource.
 super.implies(codesource) must return true.
 for each principal in this codesource's principal list:

     if the principal is an instanceof
         Principal, then the principal must
         imply the provided codesource's Subject.
     if the principal is not an instanceof
         Principal, then the provided
         codesource's Subject must have an
         associated Principal, P, where
         P.getClass().getName equals principal.principalClass,
         and P.getName() equals principal.principalName.



Params:
codesource – the CodeSource to compare against.
Returns:
true if this SubjectCodeSource implies
         the specified CodeSource./**
     * Returns true if this <code>SubjectCodeSource</code> object "implies"
     * the specified <code>CodeSource</code>.
     * More specifically, this method makes the following checks.
     * If any fail, it returns false.  If they all succeed, it returns true.
     *
     * <p>
     * <ol>
     * <li> The provided codesource must not be <code>null</code>.
     * <li> codesource must be an instance of <code>SubjectCodeSource</code>.
     * <li> super.implies(codesource) must return true.
     * <li> for each principal in this codesource's principal list:
     * <ol>
     * <li>     if the principal is an instanceof
     *          <code>Principal</code>, then the principal must
     *          imply the provided codesource's <code>Subject</code>.
     * <li>     if the principal is not an instanceof
     *          <code>Principal</code>, then the provided
     *          codesource's <code>Subject</code> must have an
     *          associated <code>Principal</code>, <i>P</i>, where
     *          P.getClass().getName equals principal.principalClass,
     *          and P.getName() equals principal.principalName.
     * </ol>
     * </ol>
     *
     * <p>
     *
     * @param codesource the <code>CodeSource</code> to compare against.
     *
     * @return true if this <code>SubjectCodeSource</code> implies
     *          the specified <code>CodeSource</code>.
     */
    public boolean implies(CodeSource codesource) {

        LinkedList<PrincipalEntry> subjectList = null;

        if (codesource == null ||
            !(codesource instanceof SubjectCodeSource) ||
            !(super.implies(codesource))) {

            if (debug != null)
                debug.println("\tSubjectCodeSource.implies: FAILURE 1");
            return false;
        }

        SubjectCodeSource that = (SubjectCodeSource)codesource;

        // if the principal list in the policy "implies"
        // the Subject associated with the current AccessControlContext,
        // then return true

        if (this.principals == null) {
            if (debug != null)
                debug.println("\tSubjectCodeSource.implies: PASS 1");
            return true;
        }

        if (that.getSubject() == null ||
            that.getSubject().getPrincipals().size() == 0) {
            if (debug != null)
                debug.println("\tSubjectCodeSource.implies: FAILURE 2");
            return false;
        }

        ListIterator<PrincipalEntry> li = this.principals.listIterator(0);
        while (li.hasNext()) {
            PrincipalEntry pppe = li.next();
            try {

                // use new Principal.implies method

                Class<?> pClass = Class.forName(pppe.principalClass,
                                                true, sysClassLoader);
                if (!Principal.class.isAssignableFrom(pClass)) {
                    // not the right subtype
                    throw new ClassCastException(pppe.principalClass +
                                                 " is not a Principal");
                }
                Constructor<?> c = pClass.getConstructor(PARAMS);
                Principal p = (Principal)c.newInstance(new Object[] {
                                                       pppe.principalName });

                if (!p.implies(that.getSubject())) {
                    if (debug != null)
                        debug.println("\tSubjectCodeSource.implies: FAILURE 3");
                    return false;
                } else {
                    if (debug != null)
                        debug.println("\tSubjectCodeSource.implies: PASS 2");
                    return true;
                }
            } catch (Exception e) {

                // simply compare Principals

                if (subjectList == null) {

                    if (that.getSubject() == null) {
                        if (debug != null)
                            debug.println("\tSubjectCodeSource.implies: " +
                                        "FAILURE 4");
                        return false;
                    }
                    Iterator<Principal> i =
                                that.getSubject().getPrincipals().iterator();

                    subjectList = new LinkedList<PrincipalEntry>();
                    while (i.hasNext()) {
                        Principal p = i.next();
                        PrincipalEntry spppe = new PrincipalEntry
                                (p.getClass().getName(), p.getName());
                        subjectList.add(spppe);
                    }
                }

                if (!subjectListImpliesPrincipalEntry(subjectList, pppe)) {
                    if (debug != null)
                        debug.println("\tSubjectCodeSource.implies: FAILURE 5");
                    return false;
                }
            }
        }

        if (debug != null)
            debug.println("\tSubjectCodeSource.implies: PASS 3");
        return true;
    }

    
This method returns, true, if the provided subjectList
"contains" the Principal specified
in the provided pppe argument.
Note that the provided pppe argument may have
wildcards (*) for the Principal class and name,
which need to be considered.

Params:
subjectList – a list of PolicyParser.PrincipalEntry objects
         that correspond to all the Principals in the Subject currently
         on this thread's AccessControlContext. 
pppe – the Principals specified in a grant entry.
Returns:
true if the provided subjectList "contains"
         the Principal specified in the provided
         pppe argument./**
     * This method returns, true, if the provided <i>subjectList</i>
     * "contains" the <code>Principal</code> specified
     * in the provided <i>pppe</i> argument.
     *
     * Note that the provided <i>pppe</i> argument may have
     * wildcards (*) for the <code>Principal</code> class and name,
     * which need to be considered.
     *
     * <p>
     *
     * @param subjectList a list of PolicyParser.PrincipalEntry objects
     *          that correspond to all the Principals in the Subject currently
     *          on this thread's AccessControlContext. <p>
     *
     * @param pppe the Principals specified in a grant entry.
     *
     * @return true if the provided <i>subjectList</i> "contains"
     *          the <code>Principal</code> specified in the provided
     *          <i>pppe</i> argument.
     */
    private boolean subjectListImpliesPrincipalEntry(
                LinkedList<PrincipalEntry> subjectList, PrincipalEntry pppe) {

        ListIterator<PrincipalEntry> li = subjectList.listIterator(0);
        while (li.hasNext()) {
            PrincipalEntry listPppe = li.next();

            if (pppe.getPrincipalClass().equals
                        (PrincipalEntry.WILDCARD_CLASS) ||
                pppe.getPrincipalClass().equals(listPppe.getPrincipalClass()))
            {
                if (pppe.getPrincipalName().equals
                        (PrincipalEntry.WILDCARD_NAME) ||
                    pppe.getPrincipalName().equals(listPppe.getPrincipalName()))
                    return true;
            }
        }
        return false;
    }

    
Tests for equality between the specified object and this
object. Two SubjectCodeSource objects are considered equal
if their locations are of identical value, if the two sets of
Certificates are of identical values, and if the
Subjects are equal, and if the PolicyParser.PrincipalEntry values
are of identical values.  It is not required that
the Certificates or PolicyParser.PrincipalEntry values
be in the same order.

Params:
obj – the object to test for equality with this object.
Returns:
true if the objects are considered equal, false otherwise./**
     * Tests for equality between the specified object and this
     * object. Two <code>SubjectCodeSource</code> objects are considered equal
     * if their locations are of identical value, if the two sets of
     * Certificates are of identical values, and if the
     * Subjects are equal, and if the PolicyParser.PrincipalEntry values
     * are of identical values.  It is not required that
     * the Certificates or PolicyParser.PrincipalEntry values
     * be in the same order.
     *
     * <p>
     *
     * @param obj the object to test for equality with this object.
     *
     * @return true if the objects are considered equal, false otherwise.
     */
    public boolean equals(Object obj) {

        if (obj == this)
            return true;

        if (super.equals(obj) == false)
            return false;

        if (!(obj instanceof SubjectCodeSource))
            return false;

        SubjectCodeSource that = (SubjectCodeSource)obj;

        // the principal lists must match
        try {
            if (this.getSubject() != that.getSubject())
                return false;
        } catch (SecurityException se) {
            return false;
        }

        if ((this.principals == null && that.principals != null) ||
            (this.principals != null && that.principals == null))
            return false;

        if (this.principals != null && that.principals != null) {
            if (!this.principals.containsAll(that.principals) ||
                !that.principals.containsAll(this.principals))

                return false;
        }

        return true;
    }

    
Return a hashcode for this SubjectCodeSource.

Returns:
a hashcode for this SubjectCodeSource./**
     * Return a hashcode for this <code>SubjectCodeSource</code>.
     *
     * <p>
     *
     * @return a hashcode for this <code>SubjectCodeSource</code>.
     */
    public int hashCode() {
        return super.hashCode();
    }

    
Return a String representation of this SubjectCodeSource.

Returns:
a String representation of this SubjectCodeSource./**
     * Return a String representation of this <code>SubjectCodeSource</code>.
     *
     * <p>
     *
     * @return a String representation of this <code>SubjectCodeSource</code>.
     */
    public String toString() {
        String returnMe = super.toString();
        if (getSubject() != null) {
            if (debug != null) {
                final Subject finalSubject = getSubject();
                returnMe = returnMe + "\n" +
                        java.security.AccessController.doPrivileged
                                (new java.security.PrivilegedAction<String>() {
                                public String run() {
                                    return finalSubject.toString();
                                }
                        });
            } else {
                returnMe = returnMe + "\n" + getSubject().toString();
            }
        }
        if (principals != null) {
            ListIterator<PrincipalEntry> li = principals.listIterator();
            while (li.hasNext()) {
                PrincipalEntry pppe = li.next();
                returnMe = returnMe + ResourcesMgr.getAuthResourceString("NEWLINE") +
                        pppe.getPrincipalClass() + " " +
                        pppe.getPrincipalName();
            }
        }
        return returnMe;
    }
}