register action allows a bundle to register a service
* on the specified names.
* get action allows a bundle to detect a service and
* get it.
* EndpointPermission to get the specific service.
*
* @ThreadSafe
* @version $Revision$
*/
public final class EndpointPermission extends BasicPermission {
static final long serialVersionUID = -7662148639076511574L;
/**
* The action string get.
*/
public final static String EXPORT = "export";
/**
* The action string register.
*/
public final static String IMPORT = "import";
public final static String LISTENING = "listening";
public final static String READ = "listening";
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 service used by this EndpointPermission. Must be null if not
* constructed with a service.
*/
transient final EndpointDescription endpoint;
/**
* The object classes for this EndpointPermission. Must be null if not
* constructed with a service.
*/
transient final String[] objectClass;
/**
* If this EndpointPermission 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 EndpointPermission.
*
* * 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:
*
* 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 EndpointPermission(String name, String actions) {
this(name, parseActions(actions));
if ((filter != null) && ((action_mask & ACTION_ALL) != ACTION_EXPORT)) {
throw new IllegalArgumentException("invalid action string for filter expression");
}
}
/**
* Creates a new requested EndpointPermission object to be
* used by code that must perform checkPermission for the
* get action. EndpointPermission objects
* created with this constructor cannot be added to a
* EndpointPermission permission collection.
*
* @param endpoint
* 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 EndpointPermission(EndpointDescription endpoint, String actions) {
super(createName(endpoint));
setTransients(null, parseActions(actions));
this.endpoint = endpoint;
this.objectClass = (String[])endpoint.getProperties().get(Constants.OBJECTCLASS);
if ((action_mask & ACTION_ALL) != ACTION_EXPORT) {
throw new IllegalArgumentException("invalid action string");
}
}
/**
* Create a permission name from a EndpointDescription TODO Needs work
*
* @param endpoint
* EndpointDescription to use to create permission name.
* @return permission name.
*/
private static String createName(EndpointDescription endpoint) {
if (endpoint == null) {
throw new IllegalArgumentException("reference must not be null");
}
StringBuffer sb = new StringBuffer("(service.id=");
// TODO sb.append(endpoint.getProperty(Constants.SERVICE_ID));
sb.append(")");
return sb.toString();
}
/**
* Package private constructor used by EndpointPermissionCollection.
*
* @param name
* class name
* @param mask
* action mask
*/
EndpointPermission(String name, int mask) {
super(name);
setTransients(parseFilter(name), mask);
this.endpoint = 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_EXPORT;
} 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_IMPORT;
} 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 EndpointPermission 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 EndpointPermission)) {
return false;
}
EndpointPermission requested = (EndpointPermission)p;
if (endpoint != 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 EndpointPermission which has already be
* validated as a proper argument. The requested
* EndpointPermission 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(EndpointPermission 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 EndpointDescription */
String[] requestedNames = requested.objectClass;
if (requestedNames == null) {
return super.implies(requested);
}
/* requested permission created with EndpointDescription */
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_EXPORT) == ACTION_EXPORT) {
sb.append(EXPORT);
comma = true;
}
if ((mask & ACTION_IMPORT) == ACTION_IMPORT) {
if (comma)
sb.append(',');
sb.append(IMPORT);
}
actions = result = sb.toString();
}
return result;
}
/**
* Returns a new PermissionCollection object for storing
* EndpointPermission objects.
*
* @return A new PermissionCollection object suitable for storing
* EndpointPermission objects.
*/
public PermissionCollection newPermissionCollection() {
return new EndpointPermissionCollection();
}
/**
* Determines the equality of two EndpointPermission objects.
*
* Checks that specified object has the same class name and action as this
* EndpointPermission.
*
* @param obj
* The object to test for equality.
* @return true if obj is a EndpointPermission, and has the
* same class name and actions as this
* EndpointPermission object; false
* otherwise.
*/
public boolean equals(Object obj) {
if (obj == this) {
return true;
}
if (!(obj instanceof EndpointPermission)) {
return false;
}
EndpointPermission sp = (EndpointPermission)obj;
return (action_mask == sp.action_mask) && getName().equals(sp.getName())
&& ((endpoint == sp.endpoint) || ((endpoint != null) && (sp.endpoint != null) && endpoint
.equals(sp.endpoint)));
}
/**
* 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 (endpoint != null) {
h = 31 * h + endpoint.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 (endpoint != 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 EndpointPermission#implies(Permission)>.
*
* @return a dictionary of properties for this permission.
*/
private Dictionary/*EndpointPermissionCollection object
* has been marked read-only.
*/
public void add(final Permission permission) {
if (!(permission instanceof EndpointPermission)) {
throw new IllegalArgumentException("invalid permission: " + permission);
}
if (isReadOnly()) {
throw new SecurityException("attempt to add a Permission to a " + "readonly PermissionCollection");
}
final EndpointPermission sp = (EndpointPermission)permission;
if (sp.endpoint != 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 EndpointPermission existing = (EndpointPermission)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 EndpointPermission(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 EndpointPermission)) {
return false;
}
final EndpointPermission requested = (EndpointPermission)permission;
/* if requested permission has a filter, then it is an invalid argument */
if (requested.filter != null) {
return false;
}
int effective = EndpointPermission.ACTION_NONE;
Collection perms;
synchronized (this) {
final int desired = requested.action_mask;
/* short circuit if the "*" Permission was added */
if (all_allowed) {
EndpointPermission sp = (EndpointPermission)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 EndpointDescription */
if (requestedNames == null) {
effective |= effective(requested.getName(), desired, effective);
if ((effective & desired) == desired) {
return true;
}
}
/* requested permission created with EndpointDescription */
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 (((EndpointPermission)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;
EndpointPermission sp = (EndpointPermission)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 = (EndpointPermission)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 EndpointPermission
* objects in the container.
*
* @return Enumeration of all the EndpointPermission 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);
}
}