/*
* Copyright (c) OSGi Alliance (2000, 2012). All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.osgi.framework;
import java.io.IOException;
import java.io.NotSerializableException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.ObjectStreamField;
import java.security.AccessController;
import java.security.BasicPermission;
import java.security.Permission;
import java.security.PermissionCollection;
import java.security.PrivilegedAction;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Hashtable;
import java.util.List;
import java.util.Map;
/**
* A bundle's authority to import or export a package.
*
* <p>
* A package is a dot-separated string that defines a fully qualified Java
* package.
* <p>
* For example:
*
* <pre>
* org.osgi.service.http
* </pre>
*
* <p>
* {@code PackagePermission} has three actions: {@code exportonly},
* {@code import} and {@code export}. The {@code export} action, which is
* deprecated, implies the {@code import} action.
*
* @ThreadSafe
* @version $Id: e993fbc36b6bff84182a8594af5af3cad8c4e2a3 $
*/
public final class PackagePermission extends BasicPermission {
static final long serialVersionUID = -5107705877071099135L;
/**
* The action string {@code export}. The {@code export} action implies the
* {@code import} action.
*
* @deprecated Since 1.5. Use {@code exportonly} instead.
*/
public final static String EXPORT = "export";
/**
* The action string {@code exportonly}. The {@code exportonly} action does
* not imply the {@code import} action.
*
* @since 1.5
*/
public final static String EXPORTONLY = "exportonly";
/**
* The action string {@code import}.
*/
public final static String IMPORT = "import";
private final static int ACTION_EXPORT = 0x00000001;
private final static int ACTION_IMPORT = 0x00000002;
private final static int ACTION_ALL = ACTION_EXPORT | ACTION_IMPORT;
final static int ACTION_NONE = 0;
/**
* The actions mask.
*/
transient int action_mask;
/**
* The actions in canonical form.
*
* @serial
*/
private volatile String actions = null;
/**
* The bundle used by this PackagePermission.
*/
transient final Bundle bundle;
/**
* If this PackagePermission was constructed with a filter, this holds a
* Filter matching object used to evaluate the filter in implies.
*/
transient Filter filter;
/**
* This map holds the properties of the permission, used to match a filter
* in implies. This is not initialized until necessary, and then cached in
* this object.
*/
private transient volatile Map<String, Object> properties;
/**
* Creates a new {@code PackagePermission} object.
*
* <p>
* The name is specified as a normal Java package name: a dot-separated
* string. Wildcards may be used.
*
* <pre>
* name ::= <package name> | <package name ending in ".*"> | *
* </pre>
*
* Examples:
*
* <pre>
* org.osgi.service.http
* javax.servlet.*
* *
* </pre>
*
* For the {@code import} action, the name can also be a filter expression.
* The filter gives access to the following attributes:
* <ul>
* <li>signer - A Distinguished Name chain used to sign the exporting
* bundle. Wildcards in a DN are not matched according to the filter string
* rules, but according to the rules defined for a DN chain.</li>
* <li>location - The location of the exporting bundle.</li>
* <li>id - The bundle ID of the exporting bundle.</li>
* <li>name - The symbolic name of the exporting bundle.</li>
* <li>package.name - The name of the requested package.</li>
* </ul>
* Filter attribute names are processed in a case sensitive manner.
*
* <p>
* Package Permissions are granted over all possible versions of a package.
*
* A bundle that needs to export a package must have the appropriate
* {@code PackagePermission} for that package; similarly, a bundle that
* needs to import a package must have the appropriate
* {@code PackagePermssion} for that package.
* <p>
* Permission is granted for both classes and resources.
*
* @param name Package name or filter expression. A filter expression can
* only be specified if the specified action is {@code import}.
* @param actions {@code exportonly},{@code import} (canonical order).
* @throws IllegalArgumentException If the specified name is a filter
* expression and either the specified action is not {@code import}
* or the filter has an invalid syntax.
*/
public PackagePermission(String name, String actions) {
this(name, parseActions(actions));
if ((filter != null) && ((action_mask & ACTION_ALL) != ACTION_IMPORT)) {
throw new IllegalArgumentException("invalid action string for filter expression");
}
}
/**
* Creates a new requested {@code PackagePermission} object to be used by
* code that must perform {@code checkPermission} for the {@code import}
* action. {@code PackagePermission} objects created with this constructor
* cannot be added to a {@code PackagePermission} permission collection.
*
* @param name The name of the requested package to import.
* @param exportingBundle The bundle exporting the requested package.
* @param actions The action {@code import}.
* @throws IllegalArgumentException If the specified action is not
* {@code import} or the name is a filter expression.
* @since 1.5
*/
public PackagePermission(String name, Bundle exportingBundle, String actions) {
super(name);
setTransients(name, parseActions(actions));
this.bundle = exportingBundle;
if (exportingBundle == null) {
throw new IllegalArgumentException("bundle must not be null");
}
if (filter != null) {
throw new IllegalArgumentException("invalid name");
}
if ((action_mask & ACTION_ALL) != ACTION_IMPORT) {
throw new IllegalArgumentException("invalid action string");
}
}
/**
* Package private constructor used by PackagePermissionCollection.
*
* @param name package name
* @param mask action mask
*/
PackagePermission(String name, int mask) {
super(name);
setTransients(name, mask);
this.bundle = null;
}
/**
* Called by constructors and when deserialized.
*
* @param mask action mask
*/
private void setTransients(String name, int mask) {
if ((mask == ACTION_NONE) || ((mask & ACTION_ALL) != mask)) {
throw new IllegalArgumentException("invalid action string");
}
action_mask = mask;
filter = parseFilter(name);
}
/**
* Parse action string into action mask.
*
* @param actions Action string.
* @return action mask.
*/
private static int parseActions(String actions) {
boolean seencomma = false;
int mask = ACTION_NONE;
if (actions == null) {
return mask;
}
char[] a = actions.toCharArray();
int i = a.length - 1;
if (i < 0)
return mask;
while (i != -1) {
char c;
// skip whitespace
while ((i != -1) && ((c = a[i]) == ' ' || c == '\r' || c == '\n' || c == '\f' || c == '\t'))
i--;
// check for the known strings
int matchlen;
if (i >= 5 && (a[i - 5] == 'i' || a[i - 5] == 'I')
&& (a[i - 4] == 'm' || a[i - 4] == 'M')
&& (a[i - 3] == 'p' || a[i - 3] == 'P')
&& (a[i - 2] == 'o' || a[i - 2] == 'O')
&& (a[i - 1] == 'r' || a[i - 1] == 'R')
&& (a[i] == 't' || a[i] == 'T')) {
matchlen = 6;
mask |= ACTION_IMPORT;
} else
if (i >= 5 && (a[i - 5] == 'e' || a[i - 5] == 'E')
&& (a[i - 4] == 'x' || a[i - 4] == 'X')
&& (a[i - 3] == 'p' || a[i - 3] == 'P')
&& (a[i - 2] == 'o' || a[i - 2] == 'O')
&& (a[i - 1] == 'r' || a[i - 1] == 'R')
&& (a[i] == 't' || a[i] == 'T')) {
matchlen = 6;
mask |= ACTION_EXPORT | ACTION_IMPORT;
} else {
if (i >= 9 && (a[i - 9] == 'e' || a[i - 9] == 'E')
&& (a[i - 8] == 'x' || a[i - 8] == 'X')
&& (a[i - 7] == 'p' || a[i - 7] == 'P')
&& (a[i - 6] == 'o' || a[i - 6] == 'O')
&& (a[i - 5] == 'r' || a[i - 5] == 'R')
&& (a[i - 4] == 't' || a[i - 4] == 'T')
&& (a[i - 3] == 'o' || a[i - 3] == 'O')
&& (a[i - 2] == 'n' || a[i - 2] == 'N')
&& (a[i - 1] == 'l' || a[i - 1] == 'L')
&& (a[i] == 'y' || a[i] == 'Y')) {
matchlen = 10;
mask |= ACTION_EXPORT;
} else {
// parse error
throw new IllegalArgumentException("invalid permission: " + actions);
}
}
// make sure we didn't just match the tail of a word
// like "ackbarfimport". Also, skip to the comma.
seencomma = false;
while (i >= matchlen && !seencomma) {
switch (a[i - matchlen]) {
case ',' :
seencomma = true;
/* FALLTHROUGH */
case ' ' :
case '\r' :
case '\n' :
case '\f' :
case '\t' :
break;
default :
throw new IllegalArgumentException("invalid permission: " + actions);
}
i--;
}
// point i at the location of the comma minus one (or -1).
i -= matchlen;
}
if (seencomma) {
throw new IllegalArgumentException("invalid permission: " + actions);
}
return mask;
}
/**
* Parse filter string into a Filter object.
*
* @param filterString The filter string to parse.
* @return a Filter for this bundle. If the specified filterString is not a
* filter expression, then {@code null} is returned.
* @throws IllegalArgumentException If the filter syntax is invalid.
*/
private static Filter parseFilter(String filterString) {
filterString = filterString.trim();
if (filterString.charAt(0) != '(') {
return null;
}
try {
return FrameworkUtil.createFilter(filterString);
} catch (InvalidSyntaxException e) {
IllegalArgumentException iae = new IllegalArgumentException("invalid filter");
iae.initCause(e);
throw iae;
}
}
/**
* Determines if the specified permission is implied by this object.
*
* <p>
* This method checks that the package name of the target is implied by the
* package name of this object. The list of {@code PackagePermission}
* actions must either match or allow for the list of the target object to
* imply the target {@code PackagePermission} action.
* <p>
* The permission to export a package implies the permission to import the
* named package.
*
* <pre>
* x.y.*,"export" -> x.y.z,"export" is true
* *,"import" -> x.y, "import" is true
* *,"export" -> x.y, "import" is true
* x.y,"export" -> x.y.z, "export" is false
* </pre>
*
* @param p The requested permission.
* @return {@code true} if the specified permission is implied by this
* object; {@code false} otherwise.
*/
public boolean implies(Permission p) {
if (!(p instanceof PackagePermission)) {
return false;
}
PackagePermission requested = (PackagePermission) p;
if (bundle != null) {
return false;
}
// if requested permission has a filter, then it is an invalid argument
if (requested.filter != null) {
return false;
}
return implies0(requested, ACTION_NONE);
}
/**
* Internal implies method. Used by the implies and the permission
* collection implies methods.
*
* @param requested The requested PackagePermission which has already be
* validated as a proper argument. The requested PackagePermission
* must not have a filter expression.
* @param effective The effective actions with which to start.
* @return {@code true} if the specified permission is implied by this
* object; {@code false} otherwise.
*/
boolean implies0(PackagePermission requested, int effective) {
/* check actions first - much faster */
effective |= action_mask;
final int desired = requested.action_mask;
if ((effective & desired) != desired) {
return false;
}
/* Get filter if any */
Filter f = filter;
if (f == null) {
return super.implies(requested);
}
return f.matches(requested.getProperties());
}
/**
* Returns the canonical string representation of the
* {@code PackagePermission} actions.
*
* <p>
* Always returns present {@code PackagePermission} actions in the following
* order: {@code EXPORTONLY},{@code IMPORT}.
*
* @return Canonical string representation of the {@code PackagePermission}
* actions.
*/
public String getActions() {
String result = actions;
if (result == null) {
StringBuffer sb = new StringBuffer();
boolean comma = false;
int mask = action_mask;
if ((mask & ACTION_EXPORT) == ACTION_EXPORT) {
sb.append(EXPORTONLY);
comma = true;
}
if ((mask & ACTION_IMPORT) == ACTION_IMPORT) {
if (comma)
sb.append(',');
sb.append(IMPORT);
}
actions = result = sb.toString();
}
return result;
}
/**
* Returns a new {@code PermissionCollection} object suitable for storing
* {@code PackagePermission} objects.
*
* @return A new {@code PermissionCollection} object.
*/
public PermissionCollection newPermissionCollection() {
return new PackagePermissionCollection();
}
/**
* Determines the equality of two {@code PackagePermission} objects.
*
* This method checks that specified package has the same package name and
* {@code PackagePermission} actions as this {@code PackagePermission}
* object.
*
* @param obj The object to test for equality with this
* {@code PackagePermission} object.
* @return {@code true} if {@code obj} is a {@code PackagePermission}, and
* has the same package name and actions as this
* {@code PackagePermission} object; {@code false} otherwise.
*/
public boolean equals(Object obj) {
if (obj == this) {
return true;
}
if (!(obj instanceof PackagePermission)) {
return false;
}
PackagePermission pp = (PackagePermission) obj;
return (action_mask == pp.action_mask) && getName().equals(pp.getName()) && ((bundle == pp.bundle) || ((bundle != null) && bundle.equals(pp.bundle)));
}
/**
* Returns the hash code value for this object.
*
* @return A hash code value for this object.
*/
public int hashCode() {
int h = 31 * 17 + getName().hashCode();
h = 31 * h + getActions().hashCode();
if (bundle != null) {
h = 31 * h + bundle.hashCode();
}
return h;
}
/**
* WriteObject is called to save the state of this permission object to a
* stream. The actions are serialized, and the superclass takes care of the
* name.
*/
private synchronized void writeObject(java.io.ObjectOutputStream s) throws IOException {
if (bundle != null) {
throw new NotSerializableException("cannot serialize");
}
// Write out the actions. The superclass takes care of the name
// call getActions to make sure actions field is initialized
if (actions == null)
getActions();
s.defaultWriteObject();
}
/**
* readObject is called to restore the state of this permission from a
* stream.
*/
private synchronized void readObject(java.io.ObjectInputStream s) throws IOException, ClassNotFoundException {
// Read in the action, then initialize the rest
s.defaultReadObject();
setTransients(getName(), parseActions(actions));
}
/**
* Called by {@code <@link PackagePermission#implies(Permission)>}. This
* method is only called on a requested permission which cannot have a
* filter set.
*
* @return a map of properties for this permission.
*/
private Map<String, Object> getProperties() {
Map<String, Object> result = properties;
if (result != null) {
return result;
}
final Map<String, Object> map = new HashMap<String, Object>(5);
map.put("package.name", getName());
if (bundle != null) {
AccessController.doPrivileged(new PrivilegedAction<Object>() {
public Object run() {
map.put("id", new Long(bundle.getBundleId()));
map.put("location", bundle.getLocation());
String name = bundle.getSymbolicName();
if (name != null) {
map.put("name", name);
}
SignerProperty signer = new SignerProperty(bundle);
if (signer.isBundleSigned()) {
map.put("signer", signer);
}
return null;
}
});
}
return properties = map;
}
}
/**
* Stores a set of {@code PackagePermission} permissions.
*
* @see java.security.Permission
* @see java.security.Permissions
* @see java.security.PermissionCollection
*/
final class PackagePermissionCollection extends PermissionCollection {
static final long serialVersionUID = -3350758995234427603L;
/**
* Table of permissions with names.
*
* @GuardedBy this
*/
private transient Map<String, PackagePermission> permissions;
/**
* Boolean saying if "*" is in the collection.
*
* @serial
* @GuardedBy this
*/
private boolean all_allowed;
/**
* Table of permissions with filter expressions.
*
* @serial
* @GuardedBy this
*/
private Map<String, PackagePermission> filterPermissions;
/**
* Create an empty PackagePermissions object.
*/
public PackagePermissionCollection() {
permissions = new HashMap<String, PackagePermission>();
all_allowed = false;
}
/**
* Adds a permission to this permission collection.
*
* @param permission The {@code PackagePermission} object to add.
* @throws IllegalArgumentException If the specified permission is not a
* {@code PackagePermission} instance or was constructed with a
* Bundle object.
* @throws SecurityException If this {@code PackagePermissionCollection}
* object has been marked read-only.
*/
public void add(final Permission permission) {
if (!(permission instanceof PackagePermission)) {
throw new IllegalArgumentException("invalid permission: " + permission);
}
if (isReadOnly()) {
throw new SecurityException("attempt to add a Permission to a " + "readonly PermissionCollection");
}
final PackagePermission pp = (PackagePermission) permission;
if (pp.bundle != null) {
throw new IllegalArgumentException("cannot add to collection: " + pp);
}
final String name = pp.getName();
final Filter f = pp.filter;
synchronized (this) {
/* select the bucket for the permission */
Map<String, PackagePermission> pc;
if (f != null) {
pc = filterPermissions;
if (pc == null) {
filterPermissions = pc = new HashMap<String, PackagePermission>();
}
} else {
pc = permissions;
}
final PackagePermission existing = pc.get(name);
if (existing != null) {
final int oldMask = existing.action_mask;
final int newMask = pp.action_mask;
if (oldMask != newMask) {
pc.put(name, new PackagePermission(name, oldMask | newMask));
}
} else {
pc.put(name, pp);
}
if (!all_allowed) {
if (name.equals("*")) {
all_allowed = true;
}
}
}
}
/**
* Determines if the specified permissions implies the permissions expressed
* in {@code permission}.
*
* @param permission The Permission object to compare with this
* {@code PackagePermission} object.
* @return {@code true} if {@code permission} is a proper subset of a
* permission in the set; {@code false} otherwise.
*/
public boolean implies(final Permission permission) {
if (!(permission instanceof PackagePermission)) {
return false;
}
final PackagePermission requested = (PackagePermission) permission;
/* if requested permission has a filter, then it is an invalid argument */
if (requested.filter != null) {
return false;
}
String requestedName = requested.getName();
final int desired = requested.action_mask;
int effective = PackagePermission.ACTION_NONE;
Collection<PackagePermission> perms;
synchronized (this) {
Map<String, PackagePermission> pc = permissions;
PackagePermission pp;
/* short circuit if the "*" Permission was added */
if (all_allowed) {
pp = pc.get("*");
if (pp != null) {
effective |= pp.action_mask;
if ((effective & desired) == desired) {
return true;
}
}
}
/*
* strategy: Check for full match first. Then work our way up the
* name looking for matches on a.b.*
*/
pp = pc.get(requestedName);
if (pp != null) {
/* we have a direct hit! */
effective |= pp.action_mask;
if ((effective & desired) == desired) {
return true;
}
}
/* work our way up the tree... */
int last;
int offset = requestedName.length() - 1;
while ((last = requestedName.lastIndexOf(".", offset)) != -1) {
requestedName = requestedName.substring(0, last + 1) + "*";
pp = pc.get(requestedName);
if (pp != null) {
effective |= pp.action_mask;
if ((effective & desired) == desired) {
return true;
}
}
offset = last - 1;
}
/*
* we don't have to check for "*" as it was already checked before
* we were called.
*/
pc = filterPermissions;
if (pc == null) {
return false;
}
perms = pc.values();
}
/* iterate one by one over filteredPermissions */
for (PackagePermission perm : perms) {
if (perm.implies0(requested, effective)) {
return true;
}
}
return false;
}
/**
* Returns an enumeration of all {@code PackagePermission} objects in the
* container.
*
* @return Enumeration of all {@code PackagePermission} objects.
*/
public synchronized Enumeration<Permission> elements() {
List<Permission> all = new ArrayList<Permission>(permissions.values());
Map<String, PackagePermission> pc = filterPermissions;
if (pc != null) {
all.addAll(pc.values());
}
return Collections.enumeration(all);
}
/* serialization logic */
private static final ObjectStreamField[] serialPersistentFields = {new ObjectStreamField("permissions", Hashtable.class), new ObjectStreamField("all_allowed", Boolean.TYPE),
new ObjectStreamField("filterPermissions", HashMap.class) };
private synchronized void writeObject(ObjectOutputStream out) throws IOException {
Hashtable<String, PackagePermission> hashtable = new Hashtable<String, PackagePermission>(permissions);
ObjectOutputStream.PutField pfields = out.putFields();
pfields.put("permissions", hashtable);
pfields.put("all_allowed", all_allowed);
pfields.put("filterPermissions", filterPermissions);
out.writeFields();
}
private synchronized void readObject(java.io.ObjectInputStream in) throws IOException, ClassNotFoundException {
ObjectInputStream.GetField gfields = in.readFields();
Hashtable<String, PackagePermission> hashtable = (Hashtable<String, PackagePermission>) gfields.get("permissions", null);
permissions = new HashMap<String, PackagePermission>(hashtable);
all_allowed = gfields.get("all_allowed", false);
HashMap<String, PackagePermission> fp = (HashMap<String, PackagePermission>) gfields.get("filterPermissions", null);
filterPermissions = fp;
}
}