org.osgi.framework.ServicePermission Maven / Gradle / Ivy
/*
* Copyright (c) OSGi Alliance (2000, 2009). 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.Dictionary;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Hashtable;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
/**
* A bundle's authority to register or get a service.
*
* - The
register action allows a bundle to register a service on
* the specified names.
* - The
get action allows a bundle to detect a service and get
* it.
*
* 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
* ServicePermission to get the specific service.
*
* @ThreadSafe
* @version $Revision: 7189 $
*/
public final class ServicePermission extends BasicPermission {
static final long serialVersionUID = -7662148639076511574L;
/**
* The action string get.
*/
public final static String GET = "get";
/**
* The action string 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 dictionary 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 Dictionary 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.
*
*
* The name of the service is specified as a fully qualified class name.
* Wildcards may be used.
*
*
* name ::= <class name> | <class name ending in ".*"> | *
*
*
* Examples:
*
*
* org.osgi.service.http.HttpService
* org.osgi.service.http.*
* *
*
*
* For the get action, the name can also be a filter
* expression. The filter gives access to the service properties as well as
* the following attributes:
*
* - 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.
* - location - The location of the bundle publishing the service.
* - id - The bundle ID of the bundle publishing the service.
* - name - The symbolic name of the bundle publishing the service.
*
* 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.
*
*
* There are two possible actions: get and
* register. The get permission allows the owner
* of this permission to obtain a service with this name. The
* register permission allows the bundle to register a service
* under that name.
*
* @param name The service class name
* @param actions get,register (canonical order)
* @throws IllegalArgumentException If the specified name is a filter
* expression and either the specified action is not
* 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 ServicePermission object to be used
* by code that must perform checkPermission for the
* get action. ServicePermission objects created
* with this constructor cannot be added to a ServicePermission
* permission collection.
*
* @param reference The requested service.
* @param actions The action get.
* @throws IllegalArgumentException If the specified action is not
* get or reference is 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 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 ServicePermission object "implies" the
* specified permission.
*
* @param p The target permission to check.
* @return true if the specified permission is implied by this
* object; 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 true if the specified permission is implied by this
* object; 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.matchCase(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: get,
* 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 PermissionCollection object for storing
* ServicePermission objects.
*
* @return A new PermissionCollection object suitable for storing
* 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
* ServicePermission.
*
* @param obj The object to test for equality.
* @return true if obj is a ServicePermission, and has the same
* class name and actions as this ServicePermission
* object; 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 <@link ServicePermission#implies(Permission)>.
*
* @return a dictionary of properties for this permission.
*/
private Dictionary getProperties() {
Dictionary result = properties;
if (result != null) {
return result;
}
if (service == null) {
result = new Hashtable(1);
if (filter == null) {
result.put(Constants.OBJECTCLASS, new String[] {getName()});
}
return properties = result;
}
final Map props = new HashMap(4);
final Bundle bundle = service.getBundle();
if (bundle != null) {
AccessController.doPrivileged(new PrivilegedAction() {
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);
}
private static class Properties extends Dictionary {
private final Map properties;
private final ServiceReference service;
Properties(Map properties, ServiceReference service) {
this.properties = properties;
this.service = service;
}
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 int size() {
return properties.size() + service.getPropertyKeys().length;
}
public boolean isEmpty() {
// we can return false because this must never be empty
return false;
}
public Enumeration keys() {
Collection pk = properties.keySet();
String spk[] = service.getPropertyKeys();
List all = new ArrayList(pk.size() + spk.length);
all.addAll(pk);
add:
for (int i = 0, length = spk.length; i < length; i++) {
String key = spk[i];
for (Iterator iter = pk.iterator(); iter.hasNext();) {
if (key.equalsIgnoreCase((String) iter.next())) {
continue add;
}
}
all.add(key);
}
return Collections.enumeration(all);
}
public Enumeration elements() {
Collection pk = properties.keySet();
String spk[] = service.getPropertyKeys();
List all = new ArrayList(pk.size() + spk.length);
all.addAll(properties.values());
add:
for (int i = 0, length = spk.length; i < length; i++) {
String key = spk[i];
for (Iterator iter = pk.iterator(); iter.hasNext();) {
if (key.equalsIgnoreCase((String) iter.next())) {
continue add;
}
}
all.add(service.getProperty(key));
}
return Collections.enumeration(all);
}
public Object put(Object key, Object value) {
throw new UnsupportedOperationException();
}
public Object remove(Object key) {
throw new UnsupportedOperationException();
}
}
}
/**
* 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 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 filterPermissions;
/**
* Creates an empty ServicePermissions object.
*/
public ServicePermissionCollection() {
permissions = new HashMap();
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
* 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 pc;
if (f != null) {
pc = filterPermissions;
if (pc == null) {
filterPermissions = pc = new HashMap();
}
}
else {
pc = permissions;
}
final ServicePermission existing = (ServicePermission) 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
* permission.
*
* @param permission The Permission object to compare.
* @return true if permission is a proper
* subset of a permission in the set; 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 perms;
synchronized (this) {
final int desired = requested.action_mask;
/* short circuit if the "*" Permission was added */
if (all_allowed) {
ServicePermission sp = (ServicePermission) 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 pc = filterPermissions;
if (pc == null) {
return false;
}
perms = pc.values();
}
/* iterate one by one over filteredPermissions */
for (Iterator iter = perms.iterator(); iter.hasNext();) {
if (((ServicePermission) iter.next())
.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 pc = permissions;
ServicePermission sp = (ServicePermission) 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 = (ServicePermission) 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 ServicePermission
* objects in the container.
*
* @return Enumeration of all the ServicePermission objects.
*/
public synchronized Enumeration elements() {
List all = new ArrayList(permissions.values());
Map 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 hashtable = new Hashtable(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 hashtable = (Hashtable) gfields.get("permissions", null);
permissions = new HashMap(hashtable);
all_allowed = gfields.get("all_allowed", false);
filterPermissions = (HashMap) gfields.get("filterPermissions", null);
}
}