| /* |
| * Copyright (c) 1997, 2015, 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.util.ArrayList; |
| import java.util.List; |
| |
| import sun.security.util.Debug; |
| import sun.security.util.FilePermCompat; |
| import sun.security.util.SecurityConstants; |
| |
| |
| /** |
| * An AccessControlContext is used to make system resource access decisions |
| * based on the context it encapsulates. |
| * |
| * <p>More specifically, it encapsulates a context and |
| * has a single method, {@code checkPermission}, |
| * that is equivalent to the {@code checkPermission} method |
| * in the AccessController class, with one difference: The AccessControlContext |
| * {@code checkPermission} method makes access decisions based on the |
| * context it encapsulates, |
| * rather than that of the current execution thread. |
| * |
| * <p>Thus, the purpose of AccessControlContext is for those situations where |
| * a security check that should be made within a given context |
| * actually needs to be done from within a |
| * <i>different</i> context (for example, from within a worker thread). |
| * |
| * <p> An AccessControlContext is created by calling the |
| * {@code AccessController.getContext} method. |
| * The {@code getContext} method takes a "snapshot" |
| * of the current calling context, and places |
| * it in an AccessControlContext object, which it returns. A sample call is |
| * the following: |
| * |
| * <pre> |
| * AccessControlContext acc = AccessController.getContext() |
| * </pre> |
| * |
| * <p> |
| * Code within a different context can subsequently call the |
| * {@code checkPermission} method on the |
| * previously-saved AccessControlContext object. A sample call is the |
| * following: |
| * |
| * <pre> |
| * acc.checkPermission(permission) |
| * </pre> |
| * |
| * @see AccessController |
| * |
| * @author Roland Schemers |
| * @since 1.2 |
| */ |
| |
| public final class AccessControlContext { |
| |
| private ProtectionDomain[] context; |
| // isPrivileged and isAuthorized are referenced by the VM - do not remove |
| // or change their names |
| private boolean isPrivileged; |
| private boolean isAuthorized = false; |
| |
| // Note: This field is directly used by the virtual machine |
| // native codes. Don't touch it. |
| private AccessControlContext privilegedContext; |
| |
| private DomainCombiner combiner = null; |
| |
| // limited privilege scope |
| private Permission[] permissions; |
| private AccessControlContext parent; |
| private boolean isWrapped; |
| |
| // is constrained by limited privilege scope? |
| private boolean isLimited; |
| private ProtectionDomain[] limitedContext; |
| |
| private static boolean debugInit = false; |
| private static Debug debug = null; |
| |
| static Debug getDebug() |
| { |
| if (debugInit) |
| return debug; |
| else { |
| if (Policy.isSet()) { |
| debug = Debug.getInstance("access"); |
| debugInit = true; |
| } |
| return debug; |
| } |
| } |
| |
| /** |
| * Create an AccessControlContext with the given array of ProtectionDomains. |
| * Context must not be null. Duplicate domains will be removed from the |
| * context. |
| * |
| * @param context the ProtectionDomains associated with this context. |
| * The non-duplicate domains are copied from the array. Subsequent |
| * changes to the array will not affect this AccessControlContext. |
| * @throws NullPointerException if {@code context} is {@code null} |
| */ |
| public AccessControlContext(ProtectionDomain[] context) |
| { |
| if (context.length == 0) { |
| this.context = null; |
| } else if (context.length == 1) { |
| if (context[0] != null) { |
| this.context = context.clone(); |
| } else { |
| this.context = null; |
| } |
| } else { |
| List<ProtectionDomain> v = new ArrayList<>(context.length); |
| for (int i =0; i< context.length; i++) { |
| if ((context[i] != null) && (!v.contains(context[i]))) |
| v.add(context[i]); |
| } |
| if (!v.isEmpty()) { |
| this.context = new ProtectionDomain[v.size()]; |
| this.context = v.toArray(this.context); |
| } |
| } |
| } |
| |
| /** |
| * Create a new {@code AccessControlContext} with the given |
| * {@code AccessControlContext} and {@code DomainCombiner}. |
| * This constructor associates the provided |
| * {@code DomainCombiner} with the provided |
| * {@code AccessControlContext}. |
| * |
| * @param acc the {@code AccessControlContext} associated |
| * with the provided {@code DomainCombiner}. |
| * |
| * @param combiner the {@code DomainCombiner} to be associated |
| * with the provided {@code AccessControlContext}. |
| * |
| * @exception NullPointerException if the provided |
| * {@code context} is {@code null}. |
| * |
| * @exception SecurityException if a security manager is installed and the |
| * caller does not have the "createAccessControlContext" |
| * {@link SecurityPermission} |
| * @since 1.3 |
| */ |
| public AccessControlContext(AccessControlContext acc, |
| DomainCombiner combiner) { |
| |
| this(acc, combiner, false); |
| } |
| |
| /** |
| * package private to allow calls from ProtectionDomain without performing |
| * the security check for {@linkplain SecurityConstants#CREATE_ACC_PERMISSION} |
| * permission |
| */ |
| AccessControlContext(AccessControlContext acc, |
| DomainCombiner combiner, |
| boolean preauthorized) { |
| if (!preauthorized) { |
| SecurityManager sm = System.getSecurityManager(); |
| if (sm != null) { |
| sm.checkPermission(SecurityConstants.CREATE_ACC_PERMISSION); |
| this.isAuthorized = true; |
| } |
| } else { |
| this.isAuthorized = true; |
| } |
| |
| this.context = acc.context; |
| |
| // we do not need to run the combine method on the |
| // provided ACC. it was already "combined" when the |
| // context was originally retrieved. |
| // |
| // at this point in time, we simply throw away the old |
| // combiner and use the newly provided one. |
| this.combiner = combiner; |
| } |
| |
| /** |
| * package private for AccessController |
| * |
| * This "argument wrapper" context will be passed as the actual context |
| * parameter on an internal doPrivileged() call used in the implementation. |
| */ |
| AccessControlContext(ProtectionDomain caller, DomainCombiner combiner, |
| AccessControlContext parent, AccessControlContext context, |
| Permission[] perms) |
| { |
| /* |
| * Combine the domains from the doPrivileged() context into our |
| * wrapper context, if necessary. |
| */ |
| ProtectionDomain[] callerPDs = null; |
| if (caller != null) { |
| callerPDs = new ProtectionDomain[] { caller }; |
| } |
| if (context != null) { |
| if (combiner != null) { |
| this.context = combiner.combine(callerPDs, context.context); |
| } else { |
| this.context = combine(callerPDs, context.context); |
| } |
| } else { |
| /* |
| * Call combiner even if there is seemingly nothing to combine. |
| */ |
| if (combiner != null) { |
| this.context = combiner.combine(callerPDs, null); |
| } else { |
| this.context = combine(callerPDs, null); |
| } |
| } |
| this.combiner = combiner; |
| |
| Permission[] tmp = null; |
| if (perms != null) { |
| tmp = new Permission[perms.length]; |
| for (int i=0; i < perms.length; i++) { |
| if (perms[i] == null) { |
| throw new NullPointerException("permission can't be null"); |
| } |
| |
| /* |
| * An AllPermission argument is equivalent to calling |
| * doPrivileged() without any limit permissions. |
| */ |
| if (perms[i].getClass() == AllPermission.class) { |
| parent = null; |
| } |
| // Add altPath into permission for compatibility. |
| tmp[i] = FilePermCompat.newPermPlusAltPath(perms[i]); |
| } |
| } |
| |
| /* |
| * For a doPrivileged() with limited privilege scope, initialize |
| * the relevant fields. |
| * |
| * The limitedContext field contains the union of all domains which |
| * are enclosed by this limited privilege scope. In other words, |
| * it contains all of the domains which could potentially be checked |
| * if none of the limiting permissions implied a requested permission. |
| */ |
| if (parent != null) { |
| this.limitedContext = combine(parent.context, parent.limitedContext); |
| this.isLimited = true; |
| this.isWrapped = true; |
| this.permissions = tmp; |
| this.parent = parent; |
| this.privilegedContext = context; // used in checkPermission2() |
| } |
| this.isAuthorized = true; |
| } |
| |
| |
| /** |
| * package private constructor for AccessController.getContext() |
| */ |
| |
| AccessControlContext(ProtectionDomain[] context, |
| boolean isPrivileged) |
| { |
| this.context = context; |
| this.isPrivileged = isPrivileged; |
| this.isAuthorized = true; |
| } |
| |
| /** |
| * Constructor for JavaSecurityAccess.doIntersectionPrivilege() |
| */ |
| AccessControlContext(ProtectionDomain[] context, |
| AccessControlContext privilegedContext) |
| { |
| this.context = context; |
| this.privilegedContext = privilegedContext; |
| this.isPrivileged = true; |
| } |
| |
| /** |
| * Returns this context's context. |
| */ |
| ProtectionDomain[] getContext() { |
| return context; |
| } |
| |
| /** |
| * Returns true if this context is privileged. |
| */ |
| boolean isPrivileged() |
| { |
| return isPrivileged; |
| } |
| |
| /** |
| * get the assigned combiner from the privileged or inherited context |
| */ |
| DomainCombiner getAssignedCombiner() { |
| AccessControlContext acc; |
| if (isPrivileged) { |
| acc = privilegedContext; |
| } else { |
| acc = AccessController.getInheritedAccessControlContext(); |
| } |
| if (acc != null) { |
| return acc.combiner; |
| } |
| return null; |
| } |
| |
| /** |
| * Get the {@code DomainCombiner} associated with this |
| * {@code AccessControlContext}. |
| * |
| * @return the {@code DomainCombiner} associated with this |
| * {@code AccessControlContext}, or {@code null} |
| * if there is none. |
| * |
| * @exception SecurityException if a security manager is installed and |
| * the caller does not have the "getDomainCombiner" |
| * {@link SecurityPermission} |
| * @since 1.3 |
| */ |
| public DomainCombiner getDomainCombiner() { |
| |
| SecurityManager sm = System.getSecurityManager(); |
| if (sm != null) { |
| sm.checkPermission(SecurityConstants.GET_COMBINER_PERMISSION); |
| } |
| return getCombiner(); |
| } |
| |
| /** |
| * package private for AccessController |
| */ |
| DomainCombiner getCombiner() { |
| return combiner; |
| } |
| |
| boolean isAuthorized() { |
| return isAuthorized; |
| } |
| |
| /** |
| * Determines whether the access request indicated by the |
| * specified permission should be allowed or denied, based on |
| * the security policy currently in effect, and the context in |
| * this object. The request is allowed only if every ProtectionDomain |
| * in the context implies the permission. Otherwise the request is |
| * denied. |
| * |
| * <p> |
| * This method quietly returns if the access request |
| * is permitted, or throws a suitable AccessControlException otherwise. |
| * |
| * @param perm the requested permission. |
| * |
| * @exception AccessControlException if the specified permission |
| * is not permitted, based on the current security policy and the |
| * context encapsulated by this object. |
| * @exception NullPointerException if the permission to check for is null. |
| */ |
| public void checkPermission(Permission perm) |
| throws AccessControlException |
| { |
| boolean dumpDebug = false; |
| |
| if (perm == null) { |
| throw new NullPointerException("permission can't be null"); |
| } |
| if (getDebug() != null) { |
| // If "codebase" is not specified, we dump the info by default. |
| dumpDebug = !Debug.isOn("codebase="); |
| if (!dumpDebug) { |
| // If "codebase" is specified, only dump if the specified code |
| // value is in the stack. |
| for (int i = 0; context != null && i < context.length; i++) { |
| if (context[i].getCodeSource() != null && |
| context[i].getCodeSource().getLocation() != null && |
| Debug.isOn("codebase=" + context[i].getCodeSource().getLocation().toString())) { |
| dumpDebug = true; |
| break; |
| } |
| } |
| } |
| |
| dumpDebug &= !Debug.isOn("permission=") || |
| Debug.isOn("permission=" + perm.getClass().getCanonicalName()); |
| |
| if (dumpDebug && Debug.isOn("stack")) { |
| Thread.dumpStack(); |
| } |
| |
| if (dumpDebug && Debug.isOn("domain")) { |
| if (context == null) { |
| debug.println("domain (context is null)"); |
| } else { |
| for (int i=0; i< context.length; i++) { |
| debug.println("domain "+i+" "+context[i]); |
| } |
| } |
| } |
| } |
| |
| /* |
| * iterate through the ProtectionDomains in the context. |
| * Stop at the first one that doesn't allow the |
| * requested permission (throwing an exception). |
| * |
| */ |
| |
| /* if ctxt is null, all we had on the stack were system domains, |
| or the first domain was a Privileged system domain. This |
| is to make the common case for system code very fast */ |
| |
| if (context == null) { |
| checkPermission2(perm); |
| return; |
| } |
| |
| for (int i=0; i< context.length; i++) { |
| if (context[i] != null && !context[i].impliesWithAltFilePerm(perm)) { |
| if (dumpDebug) { |
| debug.println("access denied " + perm); |
| } |
| |
| if (Debug.isOn("failure") && debug != null) { |
| // Want to make sure this is always displayed for failure, |
| // but do not want to display again if already displayed |
| // above. |
| if (!dumpDebug) { |
| debug.println("access denied " + perm); |
| } |
| Thread.dumpStack(); |
| final ProtectionDomain pd = context[i]; |
| final Debug db = debug; |
| AccessController.doPrivileged (new PrivilegedAction<>() { |
| public Void run() { |
| db.println("domain that failed "+pd); |
| return null; |
| } |
| }); |
| } |
| throw new AccessControlException("access denied "+perm, perm); |
| } |
| } |
| |
| // allow if all of them allowed access |
| if (dumpDebug) { |
| debug.println("access allowed "+perm); |
| } |
| |
| checkPermission2(perm); |
| } |
| |
| /* |
| * Check the domains associated with the limited privilege scope. |
| */ |
| private void checkPermission2(Permission perm) { |
| if (!isLimited) { |
| return; |
| } |
| |
| /* |
| * Check the doPrivileged() context parameter, if present. |
| */ |
| if (privilegedContext != null) { |
| privilegedContext.checkPermission2(perm); |
| } |
| |
| /* |
| * Ignore the limited permissions and parent fields of a wrapper |
| * context since they were already carried down into the unwrapped |
| * context. |
| */ |
| if (isWrapped) { |
| return; |
| } |
| |
| /* |
| * Try to match any limited privilege scope. |
| */ |
| if (permissions != null) { |
| Class<?> permClass = perm.getClass(); |
| for (int i=0; i < permissions.length; i++) { |
| Permission limit = permissions[i]; |
| if (limit.getClass().equals(permClass) && limit.implies(perm)) { |
| return; |
| } |
| } |
| } |
| |
| /* |
| * Check the limited privilege scope up the call stack or the inherited |
| * parent thread call stack of this ACC. |
| */ |
| if (parent != null) { |
| /* |
| * As an optimization, if the parent context is the inherited call |
| * stack context from a parent thread then checking the protection |
| * domains of the parent context is redundant since they have |
| * already been merged into the child thread's context by |
| * optimize(). When parent is set to an inherited context this |
| * context was not directly created by a limited scope |
| * doPrivileged() and it does not have its own limited permissions. |
| */ |
| if (permissions == null) { |
| parent.checkPermission2(perm); |
| } else { |
| parent.checkPermission(perm); |
| } |
| } |
| } |
| |
| /** |
| * Take the stack-based context (this) and combine it with the |
| * privileged or inherited context, if need be. Any limited |
| * privilege scope is flagged regardless of whether the assigned |
| * context comes from an immediately enclosing limited doPrivileged(). |
| * The limited privilege scope can indirectly flow from the inherited |
| * parent thread or an assigned context previously captured by getContext(). |
| */ |
| AccessControlContext optimize() { |
| // the assigned (privileged or inherited) context |
| AccessControlContext acc; |
| DomainCombiner combiner = null; |
| AccessControlContext parent = null; |
| Permission[] permissions = null; |
| |
| if (isPrivileged) { |
| acc = privilegedContext; |
| if (acc != null) { |
| /* |
| * If the context is from a limited scope doPrivileged() then |
| * copy the permissions and parent fields out of the wrapper |
| * context that was created to hold them. |
| */ |
| if (acc.isWrapped) { |
| permissions = acc.permissions; |
| parent = acc.parent; |
| } |
| } |
| } else { |
| acc = AccessController.getInheritedAccessControlContext(); |
| if (acc != null) { |
| /* |
| * If the inherited context is constrained by a limited scope |
| * doPrivileged() then set it as our parent so we will process |
| * the non-domain-related state. |
| */ |
| if (acc.isLimited) { |
| parent = acc; |
| } |
| } |
| } |
| |
| // this.context could be null if only system code is on the stack; |
| // in that case, ignore the stack context |
| boolean skipStack = (context == null); |
| |
| // acc.context could be null if only system code was involved; |
| // in that case, ignore the assigned context |
| boolean skipAssigned = (acc == null || acc.context == null); |
| ProtectionDomain[] assigned = (skipAssigned) ? null : acc.context; |
| ProtectionDomain[] pd; |
| |
| // if there is no enclosing limited privilege scope on the stack or |
| // inherited from a parent thread |
| boolean skipLimited = ((acc == null || !acc.isWrapped) && parent == null); |
| |
| if (acc != null && acc.combiner != null) { |
| // let the assigned acc's combiner do its thing |
| if (getDebug() != null) { |
| debug.println("AccessControlContext invoking the Combiner"); |
| } |
| |
| // No need to clone current and assigned.context |
| // combine() will not update them |
| combiner = acc.combiner; |
| pd = combiner.combine(context, assigned); |
| } else { |
| if (skipStack) { |
| if (skipAssigned) { |
| calculateFields(acc, parent, permissions); |
| return this; |
| } else if (skipLimited) { |
| return acc; |
| } |
| } else if (assigned != null) { |
| if (skipLimited) { |
| // optimization: if there is a single stack domain and |
| // that domain is already in the assigned context; no |
| // need to combine |
| if (context.length == 1 && context[0] == assigned[0]) { |
| return acc; |
| } |
| } |
| } |
| |
| pd = combine(context, assigned); |
| if (skipLimited && !skipAssigned && pd == assigned) { |
| return acc; |
| } else if (skipAssigned && pd == context) { |
| calculateFields(acc, parent, permissions); |
| return this; |
| } |
| } |
| |
| // Reuse existing ACC |
| this.context = pd; |
| this.combiner = combiner; |
| this.isPrivileged = false; |
| |
| calculateFields(acc, parent, permissions); |
| return this; |
| } |
| |
| |
| /* |
| * Combine the current (stack) and assigned domains. |
| */ |
| private static ProtectionDomain[] combine(ProtectionDomain[] current, |
| ProtectionDomain[] assigned) { |
| |
| // current could be null if only system code is on the stack; |
| // in that case, ignore the stack context |
| boolean skipStack = (current == null); |
| |
| // assigned could be null if only system code was involved; |
| // in that case, ignore the assigned context |
| boolean skipAssigned = (assigned == null); |
| |
| int slen = (skipStack) ? 0 : current.length; |
| |
| // optimization: if there is no assigned context and the stack length |
| // is less then or equal to two; there is no reason to compress the |
| // stack context, it already is |
| if (skipAssigned && slen <= 2) { |
| return current; |
| } |
| |
| int n = (skipAssigned) ? 0 : assigned.length; |
| |
| // now we combine both of them, and create a new context |
| ProtectionDomain[] pd = new ProtectionDomain[slen + n]; |
| |
| // first copy in the assigned context domains, no need to compress |
| if (!skipAssigned) { |
| System.arraycopy(assigned, 0, pd, 0, n); |
| } |
| |
| // now add the stack context domains, discarding nulls and duplicates |
| outer: |
| for (int i = 0; i < slen; i++) { |
| ProtectionDomain sd = current[i]; |
| if (sd != null) { |
| for (int j = 0; j < n; j++) { |
| if (sd == pd[j]) { |
| continue outer; |
| } |
| } |
| pd[n++] = sd; |
| } |
| } |
| |
| // if length isn't equal, we need to shorten the array |
| if (n != pd.length) { |
| // optimization: if we didn't really combine anything |
| if (!skipAssigned && n == assigned.length) { |
| return assigned; |
| } else if (skipAssigned && n == slen) { |
| return current; |
| } |
| ProtectionDomain[] tmp = new ProtectionDomain[n]; |
| System.arraycopy(pd, 0, tmp, 0, n); |
| pd = tmp; |
| } |
| |
| return pd; |
| } |
| |
| |
| /* |
| * Calculate the additional domains that could potentially be reached via |
| * limited privilege scope. Mark the context as being subject to limited |
| * privilege scope unless the reachable domains (if any) are already |
| * contained in this domain context (in which case any limited |
| * privilege scope checking would be redundant). |
| */ |
| private void calculateFields(AccessControlContext assigned, |
| AccessControlContext parent, Permission[] permissions) |
| { |
| ProtectionDomain[] parentLimit = null; |
| ProtectionDomain[] assignedLimit = null; |
| ProtectionDomain[] newLimit; |
| |
| parentLimit = (parent != null)? parent.limitedContext: null; |
| assignedLimit = (assigned != null)? assigned.limitedContext: null; |
| newLimit = combine(parentLimit, assignedLimit); |
| if (newLimit != null) { |
| if (context == null || !containsAllPDs(newLimit, context)) { |
| this.limitedContext = newLimit; |
| this.permissions = permissions; |
| this.parent = parent; |
| this.isLimited = true; |
| } |
| } |
| } |
| |
| |
| /** |
| * Checks two AccessControlContext objects for equality. |
| * Checks that {@code obj} is |
| * an AccessControlContext and has the same set of ProtectionDomains |
| * as this context. |
| * |
| * @param obj the object we are testing for equality with this object. |
| * @return true if {@code obj} is an AccessControlContext, and has the |
| * same set of ProtectionDomains as this context, false otherwise. |
| */ |
| public boolean equals(Object obj) { |
| if (obj == this) |
| return true; |
| |
| if (! (obj instanceof AccessControlContext)) |
| return false; |
| |
| AccessControlContext that = (AccessControlContext) obj; |
| |
| if (!equalContext(that)) |
| return false; |
| |
| if (!equalLimitedContext(that)) |
| return false; |
| |
| return true; |
| } |
| |
| /* |
| * Compare for equality based on state that is free of limited |
| * privilege complications. |
| */ |
| private boolean equalContext(AccessControlContext that) { |
| if (!equalPDs(this.context, that.context)) |
| return false; |
| |
| if (this.combiner == null && that.combiner != null) |
| return false; |
| |
| if (this.combiner != null && !this.combiner.equals(that.combiner)) |
| return false; |
| |
| return true; |
| } |
| |
| private boolean equalPDs(ProtectionDomain[] a, ProtectionDomain[] b) { |
| if (a == null) { |
| return (b == null); |
| } |
| |
| if (b == null) |
| return false; |
| |
| if (!(containsAllPDs(a, b) && containsAllPDs(b, a))) |
| return false; |
| |
| return true; |
| } |
| |
| /* |
| * Compare for equality based on state that is captured during a |
| * call to AccessController.getContext() when a limited privilege |
| * scope is in effect. |
| */ |
| private boolean equalLimitedContext(AccessControlContext that) { |
| if (that == null) |
| return false; |
| |
| /* |
| * If neither instance has limited privilege scope then we're done. |
| */ |
| if (!this.isLimited && !that.isLimited) |
| return true; |
| |
| /* |
| * If only one instance has limited privilege scope then we're done. |
| */ |
| if (!(this.isLimited && that.isLimited)) |
| return false; |
| |
| /* |
| * Wrapped instances should never escape outside the implementation |
| * this class and AccessController so this will probably never happen |
| * but it only makes any sense to compare if they both have the same |
| * isWrapped state. |
| */ |
| if ((this.isWrapped && !that.isWrapped) || |
| (!this.isWrapped && that.isWrapped)) { |
| return false; |
| } |
| |
| if (this.permissions == null && that.permissions != null) |
| return false; |
| |
| if (this.permissions != null && that.permissions == null) |
| return false; |
| |
| if (!(this.containsAllLimits(that) && that.containsAllLimits(this))) |
| return false; |
| |
| /* |
| * Skip through any wrapped contexts. |
| */ |
| AccessControlContext thisNextPC = getNextPC(this); |
| AccessControlContext thatNextPC = getNextPC(that); |
| |
| /* |
| * The protection domains and combiner of a privilegedContext are |
| * not relevant because they have already been included in the context |
| * of this instance by optimize() so we only care about any limited |
| * privilege state they may have. |
| */ |
| if (thisNextPC == null && thatNextPC != null && thatNextPC.isLimited) |
| return false; |
| |
| if (thisNextPC != null && !thisNextPC.equalLimitedContext(thatNextPC)) |
| return false; |
| |
| if (this.parent == null && that.parent != null) |
| return false; |
| |
| if (this.parent != null && !this.parent.equals(that.parent)) |
| return false; |
| |
| return true; |
| } |
| |
| /* |
| * Follow the privilegedContext link making our best effort to skip |
| * through any wrapper contexts. |
| */ |
| private static AccessControlContext getNextPC(AccessControlContext acc) { |
| while (acc != null && acc.privilegedContext != null) { |
| acc = acc.privilegedContext; |
| if (!acc.isWrapped) |
| return acc; |
| } |
| return null; |
| } |
| |
| private static boolean containsAllPDs(ProtectionDomain[] thisContext, |
| ProtectionDomain[] thatContext) { |
| boolean match = false; |
| |
| // |
| // ProtectionDomains within an ACC currently cannot be null |
| // and this is enforced by the constructor and the various |
| // optimize methods. However, historically this logic made attempts |
| // to support the notion of a null PD and therefore this logic continues |
| // to support that notion. |
| ProtectionDomain thisPd; |
| for (int i = 0; i < thisContext.length; i++) { |
| match = false; |
| if ((thisPd = thisContext[i]) == null) { |
| for (int j = 0; (j < thatContext.length) && !match; j++) { |
| match = (thatContext[j] == null); |
| } |
| } else { |
| Class<?> thisPdClass = thisPd.getClass(); |
| ProtectionDomain thatPd; |
| for (int j = 0; (j < thatContext.length) && !match; j++) { |
| thatPd = thatContext[j]; |
| |
| // Class check required to avoid PD exposure (4285406) |
| match = (thatPd != null && |
| thisPdClass == thatPd.getClass() && thisPd.equals(thatPd)); |
| } |
| } |
| if (!match) return false; |
| } |
| return match; |
| } |
| |
| private boolean containsAllLimits(AccessControlContext that) { |
| boolean match = false; |
| Permission thisPerm; |
| |
| if (this.permissions == null && that.permissions == null) |
| return true; |
| |
| for (int i = 0; i < this.permissions.length; i++) { |
| Permission limit = this.permissions[i]; |
| Class <?> limitClass = limit.getClass(); |
| match = false; |
| for (int j = 0; (j < that.permissions.length) && !match; j++) { |
| Permission perm = that.permissions[j]; |
| match = (limitClass.equals(perm.getClass()) && |
| limit.equals(perm)); |
| } |
| if (!match) return false; |
| } |
| return match; |
| } |
| |
| |
| /** |
| * Returns the hash code value for this context. The hash code |
| * is computed by exclusive or-ing the hash code of all the protection |
| * domains in the context together. |
| * |
| * @return a hash code value for this context. |
| */ |
| |
| public int hashCode() { |
| int hashCode = 0; |
| |
| if (context == null) |
| return hashCode; |
| |
| for (int i =0; i < context.length; i++) { |
| if (context[i] != null) |
| hashCode ^= context[i].hashCode(); |
| } |
| |
| return hashCode; |
| } |
| } |
