* The target name of this {@code Permission} specifies a pair of * kerberos service principals. The first is the subordinate service principal * being entrusted to use the TGT. The second service principal designates * the target service the subordinate service principal is to * interact with on behalf of the initiating KerberosPrincipal. This * latter service principal is specified to restrict the use of a * proxiable ticket. *
* For example, to specify the "host" service use of a forwardable TGT the * target permission is specified as follows: * *
* DelegationPermission("\"host/foo.example.com@EXAMPLE.COM\" \"krbtgt/EXAMPLE.COM@EXAMPLE.COM\"");
*
* * To give the "backup" service a proxiable nfs service ticket the target permission * might be specified: * *
* DelegationPermission("\"backup/bar.example.com@EXAMPLE.COM\" \"nfs/home.EXAMPLE.COM@EXAMPLE.COM\"");
*
*
* @since 1.4
*/
public final class DelegationPermission extends BasicPermission
implements java.io.Serializable {
private static final long serialVersionUID = 883133252142523922L;
private transient String subordinate, service;
/**
* Create a new {@code DelegationPermission}
* with the specified subordinate and target principals.
*
* @param principals the name of the subordinate and target principals
*
* @throws NullPointerException if {@code principals} is {@code null}.
* @throws IllegalArgumentException if {@code principals} is empty.
*/
public DelegationPermission(String principals) {
super(principals);
init(principals);
}
/**
* Create a new {@code DelegationPermission}
* with the specified subordinate and target principals.
*
* @param principals the name of the subordinate and target principals
*
* @param actions should be null.
*
* @throws NullPointerException if {@code principals} is {@code null}.
* @throws IllegalArgumentException if {@code principals} is empty.
*/
public DelegationPermission(String principals, String actions) {
super(principals, actions);
init(principals);
}
/**
* Initialize the DelegationPermission object.
*/
private void init(String target) {
StringTokenizer t = null;
if (!target.startsWith("\"")) {
throw new IllegalArgumentException
("service principal [" + target +
"] syntax invalid: " +
"improperly quoted");
} else {
t = new StringTokenizer(target, "\"", false);
subordinate = t.nextToken();
if (t.countTokens() == 2) {
t.nextToken(); // bypass whitespace
service = t.nextToken();
} else if (t.countTokens() > 0) {
throw new IllegalArgumentException
("service principal [" + t.nextToken() +
"] syntax invalid: " +
"improperly quoted");
}
}
}
/**
* Checks if this Kerberos delegation permission object "implies" the
* specified permission.
*
* This method returns true if this {@code DelegationPermission}
* is equal to {@code p}, and returns false otherwise.
*
* @param p the permission to check against.
*
* @return true if the specified permission is implied by this object,
* false if not.
*/
@Override
public boolean implies(Permission p) {
return equals(p);
}
/**
* Checks two DelegationPermission objects for equality.
*
* @param obj the object to test for equality with this object.
*
* @return true if {@code obj} is a DelegationPermission, and
* has the same subordinate and service principal as this
* DelegationPermission object.
*/
@Override
public boolean equals(Object obj) {
if (obj == this) {
return true;
}
if (!(obj instanceof DelegationPermission)) {
return false;
}
DelegationPermission that = (DelegationPermission) obj;
return this.subordinate.equals(that.subordinate) &&
this.service.equals(that.service);
}
/**
* Returns the hash code value for this object.
*
* @return a hash code value for this object.
*/
@Override
public int hashCode() {
return 17 * subordinate.hashCode() + 31 * service.hashCode();
}
/**
* Returns a PermissionCollection object for storing
* DelegationPermission objects.
*
* DelegationPermission objects must be stored in a manner that
* allows them to be inserted into the collection in any order, but
* that also enables the PermissionCollection implies method to
* be implemented in an efficient (and consistent) manner.
*
* @return a new PermissionCollection object suitable for storing
* DelegationPermissions.
*/
@Override
public PermissionCollection newPermissionCollection() {
return new KrbDelegationPermissionCollection();
}
/**
* WriteObject is called to save the state of the DelegationPermission
* 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
{
s.defaultWriteObject();
}
/**
* readObject is called to restore the state of the
* DelegationPermission from a stream.
*/
private synchronized void readObject(java.io.ObjectInputStream s)
throws IOException, ClassNotFoundException
{
// Read in the action, then initialize the rest
s.defaultReadObject();
init(getName());
}
}
final class KrbDelegationPermissionCollection extends PermissionCollection
implements java.io.Serializable {
// Not serialized; see serialization section at end of class.
private transient ConcurrentHashMap