File Doc Category Size Date Package
ChannelBinding.java API Doc Java SE 5 API 6968 Fri Aug 26 14:58:26 BST 2005 org.ietf.jgss

ChannelBinding

java.lang.Object

public class ChannelBinding extends Object

This class encapsulates the concept of caller-provided channel binding information. Channel bindings are used to strengthen the quality with which peer entity authentication is provided during context establishment. They enable the GSS-API callers to bind the establishment of the security context to relevant characteristics like addresses or to application specific data.

The caller initiating the security context must determine the appropriate channel binding values to set in the GSSContext object. The acceptor must provide an identical binding in order to validate that received tokens possess correct channel-related characteristics.

Use of channel bindings is optional in GSS-API. ChannelBinding can be set for the {@link GSSContext GSSContext} using the {@link GSSContext#setChannelBinding(ChannelBinding) setChannelBinding} method before the first call to {@link GSSContext#initSecContext(byte[], int, int) initSecContext} or {@link GSSContext#acceptSecContext(byte[], int, int) acceptSecContext} has been performed. Unless the setChannelBinding method has been used to set the ChannelBinding for a GSSContext object, null ChannelBinding will be assumed.

Conceptually, the GSS-API concatenates the initiator and acceptor address information, and the application supplied byte array to form an octet string. The mechanism calculates a MIC over this octet string and binds the MIC to the context establishment token emitted by initSecContext method of the GSSContext interface. The same bindings are set by the context acceptor for its GSSContext object and during processing of the acceptSecContext method a MIC is calculated in the same way. The calculated MIC is compared with that found in the token, and if the MICs differ, accept will throw a GSSException with the major code set to {@link GSSException#BAD_BINDINGS BAD_BINDINGS}, and the context will not be established. Some mechanisms may include the actual channel binding data in the token (rather than just a MIC); applications should therefore not use confidential data as channel-binding components.

Individual mechanisms may impose additional constraints on addresses that may appear in channel bindings. For example, a mechanism may verify that the initiator address field of the channel binding contains the correct network address of the host system. Portable applications should therefore ensure that they either provide correct information for the address fields, or omit setting of the addressing information.

author: Mayank Upadhyay
version: 1.8, 12/19/03
since: 1.4

Fields Summary
private InetAddress
initiator
private InetAddress
acceptor
private byte[]
appData
Constructors Summary
public ChannelBinding(InetAddress initAddr, InetAddress acceptAddr, byte[] appData)
Create a ChannelBinding object with user supplied address information and data. null values can be used for any fields which the application does not want to specify.
param
initAddr the address of the context initiator. null value can be supplied to indicate that the application does not want to set this value.
param
acceptAddr the address of the context acceptor. null value can be supplied to indicate that the application does not want to set this value.
param
appData application supplied data to be used as part of the channel bindings. null value can be supplied to indicate that the application does not want to set this value.
initiator = initAddr; acceptor = acceptAddr; if (appData != null) { this.appData = new byte[appData.length]; java.lang.System.arraycopy(appData, 0, this.appData, 0, appData.length); }
public ChannelBinding(byte[] appData)
Creates a ChannelBinding object without any addressing information.
param
appData application supplied data to be used as part of the channel bindings.
this(null, null, appData);
Methods Summary
public boolean equals(java.lang.Object obj)
Compares two instances of ChannelBinding.
param
obj another ChannelBinding to compare this one with
return
true if the two ChannelBinding's contain the same values for the initiator and acceptor addresses and the application data.
if (this == obj) return true; if (! (obj instanceof ChannelBinding)) return false; ChannelBinding cb = (ChannelBinding) obj; if ((initiator != null && cb.initiator == null) || (initiator == null && cb.initiator != null)) return false; if (initiator != null && !initiator.equals(cb.initiator)) return false; if ((acceptor != null && cb.acceptor == null) || (acceptor == null && cb.acceptor != null)) return false; if (acceptor != null && !acceptor.equals(cb.acceptor)) return false; return Arrays.equals(appData, cb.appData);
public java.net.InetAddress getAcceptorAddress()
Get the acceptor's address for this channel binding.
return
the acceptor's address. null is returned if the address has not been set.
return acceptor;
public byte[] getApplicationData()
Get the application specified data for this channel binding.
return
the application data being used as part of the ChannelBinding. null is returned if no application data has been specified for the channel binding.
if (appData == null) { return null; } byte[] retVal = new byte[appData.length]; System.arraycopy(appData, 0, retVal, 0, appData.length); return retVal;
public java.net.InetAddress getInitiatorAddress()
Get the initiator's address for this channel binding.
return
the initiator's address. null is returned if the address has not been set.
return initiator;
public int hashCode()
Returns a hashcode value for this ChannelBinding object.
return
a hashCode value
if (initiator != null) return initiator.hashCode(); else if (acceptor != null) return acceptor.hashCode(); else if (appData != null) return new String(appData).hashCode(); else return 1;