/*
* 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.AbstractMap;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Hashtable;
import java.util.List;
import java.util.Map;
import java.util.Set;
/**
* A bundle's authority to register or get a service.
* <ul>
* <li>The {@code register} action allows a bundle to register a service on the
* specified names.
* <li>The {@code get} action allows a bundle to detect a service and get it.
* </ul>
* Permission to get a service is required in order to detect events regarding
* the service. Untrusted bundles should not be able to detect the presence of
* certain services unless they have the appropriate {@code ServicePermission}
* to get the specific service.
*
* @ThreadSafe
* @version $Id: 96438ad164d7f0f4273787226298bf8208cf0034 $
*/
public final class ServicePermission extends BasicPermission {
static final long serialVersionUID = -7662148639076511574L;
/**
* The action string {@code get}.
*/
public final static String GET = "get";
/**
* The action string {@code register}.
*/
public final static String REGISTER = "register";
private final static int ACTION_GET = 0x00000001;
private final static int ACTION_REGISTER = 0x00000002;
private final static int ACTION_ALL = ACTION_GET | ACTION_REGISTER;
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 service used by this ServicePermission. Must be null if not
* constructed with a service.
*/
transient final ServiceReference<?> service;
/**
* The object classes for this ServicePermission. Must be null if not
* constructed with a service.
*/
transient final String[] objectClass;
/**
* If this ServicePermission 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;
/**
* True if constructed with a name and the name is "*" or ends with ".*".
*/
private transient boolean wildcard;
/**
* If constructed with a name and the name ends with ".*", this contains the
* name without the final "*".
*/
private transient String prefix;
/**
* Create a new ServicePermission.
*
* <p>
* The name of the service is specified as a fully qualified class name.
* Wildcards may be used.
*
* <pre>
* name ::= <class name> | <class name ending in ".*"> | *
* </pre>
*
* Examples:
*
* <pre>
* org.osgi.service.http.HttpService
* org.osgi.service.http.*
* *
* </pre>
*
* For the {@code get} action, the name can also be a filter expression. The
* filter gives access to the service properties as well as the following
* attributes:
* <ul>
* <li>signer - A Distinguished Name chain used to sign the bundle
* publishing the service. 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 bundle publishing the service.</li>
* <li>id - The bundle ID of the bundle publishing the service.</li>
* <li>name - The symbolic name of the bundle publishing the service.</li>
* </ul>
* Since the above attribute names may conflict with service property names
* used by a service, you can prefix an attribute name with '@' in the
* filter expression to match against the service property and not one of
* the above attributes. Filter attribute names are processed in a case
* sensitive manner unless the attribute references a service property.
* Service properties names are case insensitive.
*
* <p>
* There are two possible actions: {@code get} and {@code register}. The
* {@code get} permission allows the owner of this permission to obtain a
* service with this name. The {@code register} permission allows the bundle
* to register a service under that name.
*
* @param name The service class name
* @param actions {@code get},{@code register} (canonical order)
* @throws IllegalArgumentException If the specified name is a filter
* expression and either the specified action is not {@code get} or
* the filter has an invalid syntax.
*/
public ServicePermission(String name, String actions) {
this(name, parseActions(actions));
if ((filter != null) && ((action_mask & ACTION_ALL) != ACTION_GET)) {
throw new IllegalArgumentException("invalid action string for filter expression");
}
}
/**
* Creates a new requested {@code ServicePermission} object to be used by
* code that must perform {@code checkPermission} for the {@code get}
* action. {@code ServicePermission} objects created with this constructor
* cannot be added to a {@code ServicePermission} permission collection.
*
* @param reference The requested service.
* @param actions The action {@code get}.
* @throws IllegalArgumentException If the specified action is not
* {@code get} or reference is {@code null}.
* @since 1.5
*/
public ServicePermission(ServiceReference<?> reference, String actions) {
super(createName(reference));
setTransients(null, parseActions(actions));
this.service = reference;
this.objectClass = (String[]) reference.getProperty(Constants.OBJECTCLASS);
if ((action_mask & ACTION_ALL) != ACTION_GET) {
throw new IllegalArgumentException("invalid action string");
}
}
/**
* Create a permission name from a ServiceReference
*
* @param reference ServiceReference to use to create permission name.
* @return permission name.
*/
private static String createName(ServiceReference<?> reference) {
if (reference == null) {
throw new IllegalArgumentException("reference must not be null");
}
StringBuffer sb = new StringBuffer("(service.id=");
sb.append(reference.getProperty(Constants.SERVICE_ID));
sb.append(")");
return sb.toString();
}
/**
* Package private constructor used by ServicePermissionCollection.
*
* @param name class name
* @param mask action mask
*/
ServicePermission(String name, int mask) {
super(name);
setTransients(parseFilter(name), mask);
this.service = null;
this.objectClass = null;
}
/**
* Called by constructors and when deserialized.
*
* @param mask action mask
*/
private void setTransients(Filter f, int mask) {
if ((mask == ACTION_NONE) || ((mask & ACTION_ALL) != mask)) {
throw new IllegalArgumentException("invalid action string");
}
action_mask = mask;
filter = f;
if (f == null) {
String name = getName();
int l = name.length();
/* if "*" or endsWith ".*" */
wildcard = ((name.charAt(l - 1) == '*') && ((l == 1) || (name.charAt(l - 2) == '.')));
if (wildcard && (l > 1)) {
prefix = name.substring(0, l - 1);
}
}
}
/**
* 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 >= 2 && (a[i - 2] == 'g' || a[i - 2] == 'G')
&& (a[i - 1] == 'e' || a[i - 1] == 'E')
&& (a[i] == 't' || a[i] == 'T')) {
matchlen = 3;
mask |= ACTION_GET;
} else
if (i >= 7 && (a[i - 7] == 'r' || a[i - 7] == 'R')
&& (a[i - 6] == 'e' || a[i - 6] == 'E')
&& (a[i - 5] == 'g' || a[i - 5] == 'G')
&& (a[i - 4] == 'i' || a[i - 4] == 'I')
&& (a[i - 3] == 's' || a[i - 3] == 'S')
&& (a[i - 2] == 't' || a[i - 2] == 'T')
&& (a[i - 1] == 'e' || a[i - 1] == 'E')
&& (a[i] == 'r' || a[i] == 'R')) {
matchlen = 8;
mask |= ACTION_REGISTER;
} else {
// parse error
throw new IllegalArgumentException("invalid permission: " + actions);
}
// make sure we didn't just match the tail of a word
// like "ackbarfregister". 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 a {@code ServicePermission} object "implies" the specified
* permission.
*
* @param p The target permission to check.
* @return {@code true} if the specified permission is implied by this
* object; {@code false} otherwise.
*/
public boolean implies(Permission p) {
if (!(p instanceof ServicePermission)) {
return false;
}
ServicePermission requested = (ServicePermission) p;
if (service != 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 ServicePermission which has already be
* validated as a proper argument. The requested ServicePermission
* 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(ServicePermission requested, int effective) {
/* check actions first - much faster */
effective |= action_mask;
final int desired = requested.action_mask;
if ((effective & desired) != desired) {
return false;
}
/* we have name of "*" */
if (wildcard && (prefix == null)) {
return true;
}
/* if we have a filter */
Filter f = filter;
if (f != null) {
return f.matches(requested.getProperties());
}
/* if requested permission not created with ServiceReference */
String[] requestedNames = requested.objectClass;
if (requestedNames == null) {
return super.implies(requested);
}
/* requested permission created with ServiceReference */
if (wildcard) {
int pl = prefix.length();
for (int i = 0, l = requestedNames.length; i < l; i++) {
String requestedName = requestedNames[i];
if ((requestedName.length() > pl) && requestedName.startsWith(prefix)) {
return true;
}
}
} else {
String name = getName();
for (int i = 0, l = requestedNames.length; i < l; i++) {
if (requestedNames[i].equals(name)) {
return true;
}
}
}
return false;
}
/**
* Returns the canonical string representation of the actions. Always
* returns present actions in the following order: {@code get},
* {@code register}.
*
* @return The canonical string representation of the actions.
*/
public String getActions() {
String result = actions;
if (result == null) {
StringBuffer sb = new StringBuffer();
boolean comma = false;
int mask = action_mask;
if ((mask & ACTION_GET) == ACTION_GET) {
sb.append(GET);
comma = true;
}
if ((mask & ACTION_REGISTER) == ACTION_REGISTER) {
if (comma)
sb.append(',');
sb.append(REGISTER);
}
actions = result = sb.toString();
}
return result;
}
/**
* Returns a new {@code PermissionCollection} object for storing
* {@code ServicePermission} objects.
*
* @return A new {@code PermissionCollection} object suitable for storing
* {@code ServicePermission} objects.
*/
public PermissionCollection newPermissionCollection() {
return new ServicePermissionCollection();
}
/**
* Determines the equality of two ServicePermission objects.
*
* Checks that specified object has the same class name and action as this
* {@code ServicePermission}.
*
* @param obj The object to test for equality.
* @return true if obj is a {@code ServicePermission}, and has the same
* class name and actions as this {@code ServicePermission} object;
* {@code false} otherwise.
*/
public boolean equals(Object obj) {
if (obj == this) {
return true;
}
if (!(obj instanceof ServicePermission)) {
return false;
}
ServicePermission sp = (ServicePermission) obj;
return (action_mask == sp.action_mask) && getName().equals(sp.getName()) && ((service == sp.service) || ((service != null) && (service.compareTo(sp.service) == 0)));
}
/**
* Returns the hash code value for this object.
*
* @return Hash code value for this object.
*/
public int hashCode() {
int h = 31 * 17 + getName().hashCode();
h = 31 * h + getActions().hashCode();
if (service != null) {
h = 31 * h + service.hashCode();
}
return h;
}
/**
* WriteObject is called to save the state of this permission 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 (service != 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(parseFilter(getName()), parseActions(actions));
}
/**
* Called by {@code <@link ServicePermission#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;
}
if (service == null) {
result = new HashMap<String, Object>(1);
result.put(Constants.OBJECTCLASS, new String[] {getName()});
return properties = result;
}
final Map<String, Object> props = new HashMap<String, Object>(4);
final Bundle bundle = service.getBundle();
if (bundle != null) {
AccessController.doPrivileged(new PrivilegedAction<Object>() {
public Object run() {
props.put("id", new Long(bundle.getBundleId()));
props.put("location", bundle.getLocation());
String name = bundle.getSymbolicName();
if (name != null) {
props.put("name", name);
}
SignerProperty signer = new SignerProperty(bundle);
if (signer.isBundleSigned()) {
props.put("signer", signer);
}
return null;
}
});
}
return properties = new Properties(props, service);
}
static private final class Properties extends AbstractMap<String, Object> {
private final Map<String, Object> properties;
private final ServiceReference<?> service;
private transient volatile Set<Map.Entry<String, Object>> entries;
Properties(Map<String, Object> properties, ServiceReference<?> service) {
this.properties = properties;
this.service = service;
entries = null;
}
public Object get(Object k) {
if (!(k instanceof String)) {
return null;
}
String key = (String) k;
if (key.charAt(0) == '@') {
return service.getProperty(key.substring(1));
}
Object value = properties.get(key);
if (value != null) { // fall back to service properties
return value;
}
return service.getProperty(key);
}
public Set<Map.Entry<String, Object>> entrySet() {
if (entries != null) {
return entries;
}
Set<Map.Entry<String, Object>> all = new HashSet<Map.Entry<String, Object>>(properties.entrySet());
add: for (String key : service.getPropertyKeys()) {
for (String k : properties.keySet()) {
if (key.equalsIgnoreCase(k)) {
continue add;
}
}
all.add(new Entry(key, service.getProperty(key)));
}
return entries = Collections.unmodifiableSet(all);
}
static private final class Entry implements Map.Entry<String, Object> {
private final String k;
private final Object v;
Entry(String key, Object value) {
this.k = key;
this.v = value;
}
public String getKey() {
return k;
}
public Object getValue() {
return v;
}
public Object setValue(Object value) {
throw new UnsupportedOperationException();
}
public String toString() {
return k + "=" + v;
}
public int hashCode() {
return ((k == null) ? 0 : k.hashCode()) ^ ((v == null) ? 0 : v.hashCode());
}
public boolean equals(Object obj) {
if (obj == this) {
return true;
}
if (!(obj instanceof Map.Entry)) {
return false;
}
Map.Entry<?, ?> e = (Map.Entry<?, ?>) obj;
final Object key = e.getKey();
if ((k == key) || ((k != null) && k.equals(key))) {
final Object value = e.getValue();
if ((v == value) || ((v != null) && v.equals(value))) {
return true;
}
}
return false;
}
}
}
}
/**
* Stores a set of ServicePermission permissions.
*
* @see java.security.Permission
* @see java.security.Permissions
* @see java.security.PermissionCollection
*/
final class ServicePermissionCollection extends PermissionCollection {
static final long serialVersionUID = 662615640374640621L;
/**
* Table of permissions.
*
* @GuardedBy this
*/
private transient Map<String, ServicePermission> 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, ServicePermission> filterPermissions;
/**
* Creates an empty ServicePermissions object.
*/
public ServicePermissionCollection() {
permissions = new HashMap<String, ServicePermission>();
all_allowed = false;
}
/**
* Adds a permission to this permission collection.
*
* @param permission The Permission object to add.
* @throws IllegalArgumentException If the specified permission is not a
* ServicePermission object.
* @throws SecurityException If this {@code ServicePermissionCollection}
* object has been marked read-only.
*/
public void add(final Permission permission) {
if (!(permission instanceof ServicePermission)) {
throw new IllegalArgumentException("invalid permission: " + permission);
}
if (isReadOnly()) {
throw new SecurityException("attempt to add a Permission to a " + "readonly PermissionCollection");
}
final ServicePermission sp = (ServicePermission) permission;
if (sp.service != null) {
throw new IllegalArgumentException("cannot add to collection: " + sp);
}
final String name = sp.getName();
final Filter f = sp.filter;
synchronized (this) {
/* select the bucket for the permission */
Map<String, ServicePermission> pc;
if (f != null) {
pc = filterPermissions;
if (pc == null) {
filterPermissions = pc = new HashMap<String, ServicePermission>();
}
} else {
pc = permissions;
}
final ServicePermission existing = pc.get(name);
if (existing != null) {
final int oldMask = existing.action_mask;
final int newMask = sp.action_mask;
if (oldMask != newMask) {
pc.put(name, new ServicePermission(name, oldMask | newMask));
}
} else {
pc.put(name, sp);
}
if (!all_allowed) {
if (name.equals("*")) {
all_allowed = true;
}
}
}
}
/**
* Determines if a set of permissions implies the permissions expressed in
* {@code permission}.
*
* @param permission The Permission object to compare.
* @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 ServicePermission)) {
return false;
}
final ServicePermission requested = (ServicePermission) permission;
/* if requested permission has a filter, then it is an invalid argument */
if (requested.filter != null) {
return false;
}
int effective = ServicePermission.ACTION_NONE;
Collection<ServicePermission> perms;
synchronized (this) {
final int desired = requested.action_mask;
/* short circuit if the "*" Permission was added */
if (all_allowed) {
ServicePermission sp = permissions.get("*");
if (sp != null) {
effective |= sp.action_mask;
if ((effective & desired) == desired) {
return true;
}
}
}
String[] requestedNames = requested.objectClass;
/* if requested permission not created with ServiceReference */
if (requestedNames == null) {
effective |= effective(requested.getName(), desired, effective);
if ((effective & desired) == desired) {
return true;
}
}
/* requested permission created with ServiceReference */
else {
for (int i = 0, l = requestedNames.length; i < l; i++) {
if ((effective(requestedNames[i], desired, effective) & desired) == desired) {
return true;
}
}
}
Map<String, ServicePermission> pc = filterPermissions;
if (pc == null) {
return false;
}
perms = pc.values();
}
/* iterate one by one over filteredPermissions */
for (ServicePermission perm : perms) {
if (perm.implies0(requested, effective)) {
return true;
}
}
return false;
}
/**
* Consult permissions map to compute the effective permission for the
* requested permission name.
*
* @param requestedName The requested service name.
* @param desired The desired actions.
* @param effective The effective actions.
* @return The new effective actions.
*/
private int effective(String requestedName, final int desired, int effective) {
final Map<String, ServicePermission> pc = permissions;
ServicePermission sp = pc.get(requestedName);
// strategy:
// Check for full match first. Then work our way up the
// name looking for matches on a.b.*
if (sp != null) {
// we have a direct hit!
effective |= sp.action_mask;
if ((effective & desired) == desired) {
return effective;
}
}
// 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) + "*";
sp = pc.get(requestedName);
if (sp != null) {
effective |= sp.action_mask;
if ((effective & desired) == desired) {
return effective;
}
}
offset = last - 1;
}
/*
* we don't have to check for "*" as it was already checked before we
* were called.
*/
return effective;
}
/**
* Returns an enumeration of all the {@code ServicePermission} objects in
* the container.
*
* @return Enumeration of all the ServicePermission objects.
*/
public synchronized Enumeration<Permission> elements() {
List<Permission> all = new ArrayList<Permission>(permissions.values());
Map<String, ServicePermission> 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, ServicePermission> hashtable = new Hashtable<String, ServicePermission>(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, ServicePermission> hashtable = (Hashtable<String, ServicePermission>) gfields.get("permissions", null);
permissions = new HashMap<String, ServicePermission>(hashtable);
all_allowed = gfields.get("all_allowed", false);
HashMap<String, ServicePermission> fp = (HashMap<String, ServicePermission>) gfields.get("filterPermissions", null);
filterPermissions = fp;
}
}