org.ietf.jgss

Interface GSSCredential

All Superinterfaces:
Cloneable

public interface GSSCredential
extends Cloneable

This interface encapsulates the GSS-API credentials for an entity. A credential contains all the necessary cryptographic information to enable the creation of a context on behalf of the entity that it represents. It may contain multiple, distinct, mechanism specific credential elements, each containing information for a specific security mechanism, but all referring to the same entity.

A credential may be used to perform context initiation, acceptance, or both.

GSS-API implementations must impose a local access-control policy on callers to prevent unauthorized callers from acquiring credentials to which they are not entitled. GSS-API credential creation is not intended to provide a "login to the network" function, as such a function would involve the creation of new credentials rather than merely acquiring a handle to existing credentials. Such functions, if required, should be defined in implementation-specific extensions to the API.

If credential acquisition is time-consuming for a mechanism, the mechanism may choose to delay the actual acquisition until the credential is required (e.g. by GSSContext). Such mechanism- specific implementation decisions should be invisible to the calling application; thus the query methods immediately following the creation of a credential object must return valid credential data, and may therefore incur the overhead of a deferred credential acquisition.

Applications will create a credential object passing the desired parameters. The application can then use the query methods to obtain specific information about the instantiated credential object (equivalent to the gss_inquire routines). When the credential is no longer needed, the application should call the dispose (equivalent to gss_release_cred) method to release any resources held by the credential object and to destroy any cryptographically sensitive information.

Classes implementing this interface also implement the Cloneable interface. This indicates the the class will support the Cloneable.clone() method that will allow the creation of duplicate credentials. This is useful when called just before the add(GSSName,int,int,Oid,int) call to retain a copy of the original credential.

Example Code

GSSManager mgr = GSSManager.getInstance();
// start by creating a name object for the entity
GSSName name = mgr.createName("userName", GSSName.NT_USER_NAME);
// now acquire credentials for the entity
GSSCredential cred = mgr.createCredential(name,
GSSCredential.ACCEPT_ONLY);
// display credential information - name, remaining lifetime,
// and the mechanisms it has been acquired over
print(cred.getName().toString());
print(cred.getRemainingLifetime());
Oid [] mechs = cred.getMechs();
if (mechs != null)
{
for (int i = 0; i <32mechs.length; i++)
print(mechs[i].toString());
}
// release system resources held by the credential
cred.dispose();
 

Field Summary

static int
ACCEPT_ONLY
Credential usage flag requesting that it be able to be used for context acceptance only.
static int
DEFAULT_LIFETIME
A lifetime constant representing the default credential lifetime.
static int
INDEFINITE_LIFETIME
A lifetime constant representing indefinite credential lifetime.
static int
INITIATE_AND_ACCEPT
Credential usage flag requesting that it be able to be used for both context initiation and acceptance.
static int
INITIATE_ONLY
Credential usage flag requesting that it be able to be used for context initiation only.

Method Summary

void
add(GSSName aName, int initLifetime, int acceptLifetime, Oid mech, int usage)
Adds a mechanism specific credential-element to an existing credential.
void
dispose()
Releases any sensitive information that the GSSCredential object may be containing.
boolean
equals(Object another)
Tests if this GSSCredential refers to the same entity as the supplied object.
Oid[]
getMechs()
Returns an array of mechanisms supported by this credential.
GSSName
getName()
Retrieves the name of the entity that the credential asserts.
GSSName
getName(Oid mechOID)
Retrieves a mechanism name of the entity that the credential asserts.
int
getRemainingAcceptLifetime(Oid mech)
Returns the remaining lifetime is seconds for the credential to remain capable of accepting security contexts under the specified mechanism.
int
getRemainingInitLifetime(Oid mech)
Returns the remaining lifetime is seconds for the credential to remain capable of initiating security contexts under the specified mechanism.
int
getRemainingLifetime()
Returns the remaining lifetime in seconds for a credential.
int
getUsage()
Returns the credential usage flag.
int
getUsage(Oid mechOID)
Returns the credential usage flag for the specified credential mechanism.
int
hashCode()
Return the hash code of this credential.

Field Details

ACCEPT_ONLY

public static final int ACCEPT_ONLY
Credential usage flag requesting that it be able to be used for context acceptance only.
Field Value:
2

DEFAULT_LIFETIME

public static final int DEFAULT_LIFETIME
A lifetime constant representing the default credential lifetime.
Field Value:
0

INDEFINITE_LIFETIME

public static final int INDEFINITE_LIFETIME
A lifetime constant representing indefinite credential lifetime.
Field Value:
2147483647

INITIATE_AND_ACCEPT

public static final int INITIATE_AND_ACCEPT
Credential usage flag requesting that it be able to be used for both context initiation and acceptance.
Field Value:
0

INITIATE_ONLY

public static final int INITIATE_ONLY
Credential usage flag requesting that it be able to be used for context initiation only.
Field Value:
1

Method Details

add

public void add(GSSName aName,
                int initLifetime,
                int acceptLifetime,
                Oid mech,
                int usage)
            throws GSSException
Adds a mechanism specific credential-element to an existing credential. This method allows the construction of credentials one mechanism at a time.

This routine is envisioned to be used mainly by context acceptors during the creation of acceptance credentials which are to be used with a variety of clients using different security mechanisms.

This routine adds the new credential element "in-place". To add the element in a new credential, first call Cloneable.clone() to obtain a copy of this credential, then call its add() method.

Parameters:
aName - Name of the principal for whom this credential is to be acquired. Use null to specify the default principal.
initLifetime - The number of seconds that credentials should remain valid for initiating of security contexts. Use INDEFINITE_LIFETIME to request that the credentials have the maximum permitted lifetime. Use DEFAULT_LIFETIME to request the default credential lifetime.
acceptLifetime - The number of seconds that credentials should remain valid for accepting of security contexts. Use INDEFINITE_LIFETIME to request that the credentials have the maximum permitted lifetime. Use DEFAULT_LIFETIME to request the default credential lifetime.
mech - The mechanisms over which the credential is to be acquired.
usage - The intended usage for this credential object. The value of this parameter must be one of: GSSCredential, ACCEPT_ONLY, INITIATE_ONLY.
Throws:
GSSException - If this operation fails.

dispose

public void dispose()
            throws GSSException
Releases any sensitive information that the GSSCredential object may be containing. Applications should call this method as soon as the credential is no longer needed to minimize the time any sensitive information is maintained.
Throws:
GSSException - If this operation fails.

equals

public boolean equals(Object another)
Tests if this GSSCredential refers to the same entity as the supplied object. The two credentials must be acquired over the same mechanisms and must refer to the same principal. Returns true if the two GSSCredentials refer to the same entity; false otherwise. (Note that the Java language specification requires that two objects that are equal according to the Object.equals(Object) method must return the same integer result when the Object.hashCode() method is called on them.)
Overrides:
equals in interface Object
Parameters:
another - Another GSSCredential object for comparison.
Returns:
True if this object equals the other.

getMechs

public Oid[] getMechs()
            throws GSSException
Returns an array of mechanisms supported by this credential.
Returns:
The supported mechanism.
Throws:
GSSException - If this operation fails.

getName

public GSSName getName()
            throws GSSException
Retrieves the name of the entity that the credential asserts.
Returns:
The name.
Throws:
GSSException - If this operation fails.

getName

public GSSName getName(Oid mechOID)
            throws GSSException
Retrieves a mechanism name of the entity that the credential asserts. Equivalent to calling GSSName.canonicalize(Oid) on the name returned by getName().
Parameters:
mechOID - The mechanism for which information should be returned.
Returns:
The name.
Throws:
GSSException - If this operation fails.

getRemainingAcceptLifetime

public int getRemainingAcceptLifetime(Oid mech)
            throws GSSException
Returns the remaining lifetime is seconds for the credential to remain capable of accepting security contexts under the specified mechanism. A return value of INDEFINITE_LIFETIME indicates that the credential does not expire for context acceptance. A return value of 0 indicates that the credential is already expired.
Parameters:
mech - The mechanism for which information should be returned.
Returns:
The remaining lifetime.
Throws:
GSSException - If this operation fails.

getRemainingInitLifetime

public int getRemainingInitLifetime(Oid mech)
            throws GSSException
Returns the remaining lifetime is seconds for the credential to remain capable of initiating security contexts under the specified mechanism. A return value of INDEFINITE_LIFETIME indicates that the credential does not expire for context initiation. A return value of 0 indicates that the credential is already expired.
Parameters:
mech - The mechanism for which information should be returned.
Returns:
The remaining lifetime.
Throws:
GSSException - If this operation fails.

getRemainingLifetime

public int getRemainingLifetime()
            throws GSSException
Returns the remaining lifetime in seconds for a credential. The remaining lifetime is the minimum lifetime for any of the underlying credential mechanisms. A return value of INDEFINITE_LIFETIME indicates that the credential does not expire. A return value of 0 indicates that the credential is already expired.
Returns:
The remaining lifetime.
Throws:
GSSException - If this operation fails.

getUsage

public int getUsage()
            throws GSSException
Returns the credential usage flag. The return value will be one of INITIATE_ONLY, ACCEPT_ONLY, or INITIATE_AND_ACCEPT.
Returns:
The credential usage flag.
Throws:
GSSException - If this operation fails.

getUsage

public int getUsage(Oid mechOID)
            throws GSSException
Returns the credential usage flag for the specified credential mechanism. The return value will be one of INITIATE_ONLY, ACCEPT_ONLY, or INITIATE_AND_ACCEPT.
Parameters:
mechOID - The mechanism for which information should be returned.
Returns:
The credential usage flag.
Throws:
GSSException - If this operation fails.

hashCode

public int hashCode()
Return the hash code of this credential. When overriding equals(Object), it is necessary to override hashCode() as well.
Overrides:
hashCode in interface Object
Returns:
the hash code that must be the same for two credentials if equals(Object) returns true.

GSSCredential.java -- GSS credential interface. Copyright (C) 2004 Free Software Foundation, Inc. This file is part of GNU Classpath. GNU Classpath is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. GNU Classpath is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GNU Classpath; see the file COPYING. If not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. Linking this library statically or dynamically with other modules is making a combined work based on this library. Thus, the terms and conditions of the GNU General Public License cover the whole combination. As a special exception, the copyright holders of this library give you permission to link this library with independent modules to produce an executable, regardless of the license terms of these independent modules, and to copy and distribute the resulting executable under terms of your choice, provided that you also meet, for each linked independent module, the terms and conditions of the license of that module. An independent module is a module which is not derived from or based on this library. If you modify this library, you may extend this exception to your version of the library, but you are not obligated to do so. If you do not wish to do so, delete this exception statement from your version. The documentation comments of this class are derived from the text of RFC 2853: Generic Security Service API Version 2: Java Bindings. That document is covered under the following license notice: Copyright (C) The Internet Society (2000). All Rights Reserved. This document and translations of it may be copied and furnished to others, and derivative works that comment on or otherwise explain it or assist in its implementation may be prepared, copied, published and distributed, in whole or in part, without restriction of any kind, provided that the above copyright notice and this paragraph are included on all such copies and derivative works. However, this document itself may not be modified in any way, such as by removing the copyright notice or references to the Internet Society or other Internet organizations, except as needed for the purpose of developing Internet standards in which case the procedures for copyrights defined in the Internet Standards process must be followed, or as required to translate it into languages other than English. The limited permissions granted above are perpetual and will not be revoked by the Internet Society or its successors or assigns. This document and the information contained herein is provided on an "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.