/*
* Copyright (c) OSGi Alliance (2010, 2013). 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.service.coordinator;
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.security.cert.X509Certificate;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.osgi.framework.Bundle;
import org.osgi.framework.Filter;
import org.osgi.framework.FrameworkUtil;
import org.osgi.framework.InvalidSyntaxException;
/**
* A bundle's authority to create or use a {@link Coordination}.
*
* <p>
* {@code CoordinationPermission} has three actions: {@code initiate},
* {@code participate} and {@code admin}.
*
* @ThreadSafe
* @author $Id: 13aa34eaea5f268a315be475fa8bb7b2718415bd $
*/
public final class CoordinationPermission extends BasicPermission {
private static final long serialVersionUID = 1L;
/**
* The action string {@code initiate}.
*/
public final static String INITIATE = "initiate";
/**
* The action string {@code participate}.
*/
public final static String PARTICIPATE = "participate";
/**
* The action string {@code admin}.
*/
public final static String ADMIN = "admin";
private final static int ACTION_INITIATE = 0x00000001;
private final static int ACTION_PARTICIPATE = 0x00000002;
private final static int ACTION_ADMIN = 0x00000004;
private final static int ACTION_ALL = ACTION_INITIATE | ACTION_PARTICIPATE | ACTION_ADMIN;
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 CoordinationPermission.
*/
transient final Bundle bundle;
/**
* If this CoordinationPermission 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 granted {@code CoordinationPermission} object.
*
* This constructor must only be used to create a permission that is going
* to be checked.
* <p>
* Examples:
*
* <pre>
* (coordination.name=com.acme.*)
* (&(signer=\*,o=ACME,c=US)(coordination.name=com.acme.*))
* (signer=\*,o=ACME,c=US)
* </pre>
*
* <p>
* When a signer key is used within the filter expression the signer value
* must escape the special filter chars ('*', '(', ')').
* <p>
* The name is specified as 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>coordination.name - The name of the requested coordination.</li>
* </ul>
* Filter attribute names are processed in a case sensitive manner.
*
* @param filter A filter expression. Filter attribute names are processed
* in a case sensitive manner. A special value of {@code "*"} can be
* used to match all coordinations.
* @param actions {@code admin}, {@code initiate} or {@code participate}
* (canonical order).
* @throws IllegalArgumentException If the filter has an invalid syntax.
*/
public CoordinationPermission(String filter, String actions) {
this(parseFilter(filter), parseActions(actions));
}
/**
* Creates a new requested {@code CoordinationPermission} object to be used
* by the code that must perform {@code checkPermission}.
* {@code CoordinationPermission} objects created with this constructor
* cannot be added to an {@code CoordinationPermission} permission
* collection.
*
* @param coordinationName The name of the requested Coordination.
* @param coordinationBundle The bundle which
* {@link Coordination#getBundle() created} the requested
* Coordination.
* @param actions {@code admin}, {@code initiate} or {@code participate}
* (canonical order).
*/
public CoordinationPermission(String coordinationName, Bundle coordinationBundle, String actions) {
super(coordinationName);
setTransients(null, parseActions(actions));
this.bundle = coordinationBundle;
if (coordinationName == null) {
throw new NullPointerException("coordinationName must not be null");
}
if (coordinationBundle == null) {
throw new NullPointerException("coordinationBundle must not be null");
}
}
/**
* Package private constructor used by CoordinationPermissionCollection.
*
* @param filter name filter
* @param mask action mask
*/
CoordinationPermission(Filter filter, int mask) {
super((filter == null) ? "*" : filter.toString());
setTransients(filter, mask);
this.bundle = null;
}
/**
* Called by constructors and when deserialized.
*
* @param filter Permission's filter or {@code null} for wildcard.
* @param mask action mask
*/
private void setTransients(Filter filter, int mask) {
this.filter = filter;
if ((mask == ACTION_NONE) || ((mask & ACTION_ALL) != mask)) {
throw new IllegalArgumentException("invalid action string");
}
this.action_mask = mask;
}
/**
* 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 >= 4 && (a[i - 4] == 'a' || a[i - 4] == 'A')
&& (a[i - 3] == 'd' || a[i - 3] == 'D')
&& (a[i - 2] == 'm' || a[i - 2] == 'M')
&& (a[i - 1] == 'i' || a[i - 1] == 'I')
&& (a[i] == 'n' || a[i] == 'N')) {
matchlen = 5;
mask |= ACTION_ADMIN;
}
else
if (i >= 7 && (a[i - 7] == 'i' || a[i - 7] == 'I')
&& (a[i - 6] == 'n' || a[i - 6] == 'N')
&& (a[i - 5] == 'i' || a[i - 5] == 'I')
&& (a[i - 4] == 't' || a[i - 4] == 'T')
&& (a[i - 3] == 'i' || a[i - 3] == 'I')
&& (a[i - 2] == 'a' || a[i - 2] == 'A')
&& (a[i - 1] == 't' || a[i - 1] == 'T')
&& (a[i] == 'e' || a[i] == 'E')) {
matchlen = 8;
mask |= ACTION_INITIATE;
}
else {
if (i >= 10 && (a[i - 10] == 'p' || a[i - 10] == 'P')
&& (a[i - 9] == 'a' || a[i - 9] == 'A')
&& (a[i - 8] == 'r' || a[i - 8] == 'R')
&& (a[i - 7] == 't' || a[i - 7] == 'T')
&& (a[i - 6] == 'i' || a[i - 6] == 'I')
&& (a[i - 5] == 'c' || a[i - 5] == 'C')
&& (a[i - 4] == 'i' || a[i - 4] == 'I')
&& (a[i - 3] == 'p' || a[i - 3] == 'P')
&& (a[i - 2] == 'a' || a[i - 2] == 'A')
&& (a[i - 1] == 't' || a[i - 1] == 'T')
&& (a[i] == 'e' || a[i] == 'E')) {
matchlen = 11;
mask |= ACTION_PARTICIPATE;
} else {
// parse error
throw new IllegalArgumentException("invalid permission: " + actions);
}
}
// make sure we didn't just match the tail of a word
// like "ackbarfadmin". 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.
* @throws IllegalArgumentException If the filter syntax is invalid.
*/
private static Filter parseFilter(String filterString) {
filterString = filterString.trim();
if (filterString.equals("*")) {
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 filter of the target is implied by the
* coordination name of this object. The list of
* {@code CoordinationPermission} actions must either match or allow for the
* list of the target object to imply the target
* {@code CoordinationPermission} action.
* <p>
*
* @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 CoordinationPermission)) {
return false;
}
CoordinationPermission requested = (CoordinationPermission) 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 CoordinationPermission which has already
* be validated as a proper argument. The requested
* CoordinationPermission 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(CoordinationPermission 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 */
Filter f = filter;
if (f == null) {
// it's "*"
return true;
}
return f.matches(requested.getProperties());
}
/**
* Returns the canonical string representation of the
* {@code CoordinationPermission} actions.
*
* <p>
* Always returns present {@code CoordinationPermission} actions in the
* following order: {@code admin}, {@code initiate}, {@code participate}.
*
* @return Canonical string representation of the
* {@code CoordinationPermission} actions.
*/
public String getActions() {
String result = actions;
if (result == null) {
StringBuffer sb = new StringBuffer();
boolean comma = false;
int mask = action_mask;
if ((mask & ACTION_ADMIN) == ACTION_ADMIN) {
sb.append(ADMIN);
comma = true;
}
if ((mask & ACTION_INITIATE) == ACTION_INITIATE) {
if (comma)
sb.append(',');
sb.append(INITIATE);
comma = true;
}
if ((mask & ACTION_PARTICIPATE) == ACTION_PARTICIPATE) {
if (comma)
sb.append(',');
sb.append(PARTICIPATE);
comma = true;
}
actions = result = sb.toString();
}
return result;
}
/**
* Returns a new {@code PermissionCollection} object suitable for storing
* {@code CoordinationPermission} objects.
*
* @return A new {@code PermissionCollection} object.
*/
public PermissionCollection newPermissionCollection() {
return new CoordinationPermissionCollection();
}
/**
* Determines the equality of two {@code CoordinationPermission} objects.
*
* This method checks that specified permission has the same name and
* {@code CoordinationPermission} actions as this
* {@code CoordinationPermission} object.
*
* @param obj The object to test for equality with this
* {@code CoordinationPermission} object.
* @return {@code true} if {@code obj} is a {@code CoordinationPermission},
* and has the same name and actions as this
* {@code CoordinationPermission} object; {@code false} otherwise.
*/
public boolean equals(Object obj) {
if (obj == this) {
return true;
}
if (!(obj instanceof CoordinationPermission)) {
return false;
}
CoordinationPermission cp = (CoordinationPermission) obj;
return (action_mask == cp.action_mask) && getName().equals(cp.getName()) && ((bundle == cp.bundle) || ((bundle != null) && bundle.equals(cp.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(parseFilter(getName()), parseActions(actions));
}
/**
* Called by {@link CoordinationPermission#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("coordination.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;
}
}
/**
* Package private class used for filter matching on signer key during filter
* expression evaluation in the permission implies method.
*
* @Immutable
*/
final class SignerProperty {
private final Bundle bundle;
private final String pattern;
/**
* String constructor used by the filter matching algorithm to construct a
* SignerProperty from the attribute value in a filter expression.
*
* @param pattern Attribute value in the filter expression.
*/
public SignerProperty(String pattern) {
this.pattern = pattern;
this.bundle = null;
}
/**
* Used by the permission implies method to build the properties for a
* filter match.
*
* @param bundle The bundle whose signers are to be matched.
*/
SignerProperty(Bundle bundle) {
this.bundle = bundle;
this.pattern = null;
}
/**
* Used by the filter matching algorithm. This methods does NOT satisfy the
* normal equals contract. Since the class is only used in filter expression
* evaluations, it only needs to support comparing an instance created with
* a Bundle to an instance created with a pattern string from the filter
* expression.
*
* @param o SignerProperty to compare against.
* @return true if the DN name chain matches the pattern.
*/
public boolean equals(Object o) {
if (!(o instanceof SignerProperty))
return false;
SignerProperty other = (SignerProperty) o;
Bundle matchBundle = bundle != null ? bundle : other.bundle;
String matchPattern = bundle != null ? other.pattern : pattern;
Map<X509Certificate, List<X509Certificate>> signers = matchBundle.getSignerCertificates(Bundle.SIGNERS_TRUSTED);
for (List<X509Certificate> signerCerts : signers.values()) {
List<String> dnChain = new ArrayList<String>(signerCerts.size());
for (X509Certificate signerCert : signerCerts) {
dnChain.add(signerCert.getSubjectDN().getName());
}
try {
if (FrameworkUtil.matchDistinguishedNameChain(matchPattern, dnChain)) {
return true;
}
} catch (IllegalArgumentException e) {
continue; // bad pattern
}
}
return false;
}
/**
* Since the equals method does not obey the general equals contract, this
* method cannot generate hash codes which obey the equals contract.
*/
public int hashCode() {
return 31;
}
/**
* Check if the bundle is signed.
*
* @return true if constructed with a bundle that is signed.
*/
boolean isBundleSigned() {
if (bundle == null) {
return false;
}
Map<X509Certificate, List<X509Certificate>> signers = bundle.getSignerCertificates(Bundle.SIGNERS_TRUSTED);
return !signers.isEmpty();
}
}
/**
* Stores a set of {@code CoordinationPermission} permissions.
*
* @see java.security.Permission
* @see java.security.Permissions
* @see java.security.PermissionCollection
*/
final class CoordinationPermissionCollection extends PermissionCollection {
static final long serialVersionUID = -3350758995234427603L;
/**
* Collection of permissions.
*
* @serial
* @GuardedBy this
*/
private Map<String, CoordinationPermission> permissions;
/**
* Boolean saying if "*" is in the collection.
*
* @serial
* @GuardedBy this
*/
private boolean all_allowed;
/**
* Create an empty CoordinationPermissions object.
*/
public CoordinationPermissionCollection() {
permissions = new HashMap<String, CoordinationPermission>();
all_allowed = false;
}
/**
* Adds a permission to this permission collection.
*
* @param permission The {@code CoordinationPermission} object to add.
* @throws IllegalArgumentException If the specified permission is not a
* {@code CoordinationPermission} instance or was constructed with a
* Bundle object.
* @throws SecurityException If this
* {@code CoordinationPermissionCollection} object has been marked
* read-only.
*/
public void add(final Permission permission) {
if (!(permission instanceof CoordinationPermission)) {
throw new IllegalArgumentException("invalid permission: " + permission);
}
if (isReadOnly()) {
throw new SecurityException("attempt to add a Permission to a " + "readonly PermissionCollection");
}
final CoordinationPermission cp = (CoordinationPermission) permission;
if (cp.bundle != null) {
throw new IllegalArgumentException("cannot add to collection: " + cp);
}
final String name = cp.getName();
synchronized (this) {
Map<String, CoordinationPermission> pc = permissions;
final CoordinationPermission existing = pc.get(name);
if (existing != null) {
final int oldMask = existing.action_mask;
final int newMask = cp.action_mask;
if (oldMask != newMask) {
pc.put(name, new CoordinationPermission(existing.filter, oldMask | newMask));
}
} else {
pc.put(name, cp);
}
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 CoordinationPermission} 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 CoordinationPermission)) {
return false;
}
final CoordinationPermission requested = (CoordinationPermission) permission;
/* if requested permission has a filter, then it is an invalid argument */
if (requested.filter != null) {
return false;
}
int effective = CoordinationPermission.ACTION_NONE;
Collection<CoordinationPermission> perms;
synchronized (this) {
Map<String, CoordinationPermission> pc = permissions;
/* short circuit if the "*" Permission was added */
if (all_allowed) {
CoordinationPermission cp = pc.get("*");
if (cp != null) {
effective |= cp.action_mask;
final int desired = requested.action_mask;
if ((effective & desired) == desired) {
return true;
}
}
}
perms = pc.values();
}
/* iterate one by one over filteredPermissions */
for (CoordinationPermission perm : perms) {
if (perm.implies0(requested, effective)) {
return true;
}
}
return false;
}
/**
* Returns an enumeration of all {@code CoordinationPermission} objects in
* the container.
*
* @return Enumeration of all {@code CoordinationPermission} objects.
*/
public synchronized Enumeration<Permission> elements() {
List<Permission> all = new ArrayList<Permission>(permissions.values());
return Collections.enumeration(all);
}
/* serialization logic */
private static final ObjectStreamField[] serialPersistentFields = {new ObjectStreamField("permissions", HashMap.class), new ObjectStreamField("all_allowed", Boolean.TYPE)};
private synchronized void writeObject(ObjectOutputStream out) throws IOException {
ObjectOutputStream.PutField pfields = out.putFields();
pfields.put("permissions", permissions);
pfields.put("all_allowed", all_allowed);
out.writeFields();
}
private synchronized void readObject(java.io.ObjectInputStream in) throws IOException, ClassNotFoundException {
ObjectInputStream.GetField gfields = in.readFields();
permissions = (HashMap<String, CoordinationPermission>) gfields.get("permissions", null);
all_allowed = gfields.get("all_allowed", false);
}
}