SaslServer (GNU Classpath 0.94-pre Documentation)

Performs SASL authentication as a server.

A server such as an LDAP server gets an instance of this class in order to perform authentication defined by a specific SASL mechanism. Invoking methods on the SaslServer instance generates challenges corresponding to the SASL mechanism implemented by the SaslServer instance. As the authentication proceeds, the instance encapsulates the state of a SASL server's authentication exchange.

Here's an example of how an LDAP server might use a SaslServer instance. It first gets an instance of a SaslServer for the SASL mechanism requested by the client:

SaslServer ss =
      Sasl.createSaslServer(mechanism, "ldap", myFQDN, props, callbackHandler);

It can then proceed to use the server for authentication. For example, suppose the LDAP server received an LDAP BIND request containing the name of the SASL mechanism and an (optional) initial response. It then might use the server as follows:

while (!ss.isComplete()) {
   try {
      byte[] challenge = ss.evaluateResponse(response);
      if (ss.isComplete()) {
         status = ldap.sendBindResponse(mechanism, challenge, SUCCESS);
      } else {
         status = ldap.sendBindResponse(mechanism, challenge, SASL_BIND_IN_PROGRESS);
         response = ldap.readBindRequest();
      }
   } catch (SaslException x) {
      status = ldap.sendErrorResponse(x);
      break;
   }
}
if (ss.isComplete() && (status == SUCCESS)) {
   String qop = (String) sc.getNegotiatedProperty(Sasl.QOP);
   if (qop != null
         && (qop.equalsIgnoreCase("auth-int")
            || qop.equalsIgnoreCase("auth-conf"))) {
      // Use SaslServer.wrap() and SaslServer.unwrap() for future
      // communication with client
      ldap.in = new SecureInputStream(ss, ldap.in);
      ldap.out = new SecureOutputStream(ss, ldap.out);
   }
}

Since: 1.5

See Also: Sasl

Method Summary
void	dispose() Disposes of any system resources or security-sensitive information the `SaslServer` might be using.
byte[]	evaluateResponse(byte[] response) Evaluates the response data and generates a challenge.
String	getAuthorizationID() Reports the authorization ID in effect for the client of this session This method can only be called if {@link #isComplete()} returns `true`.
String	getMechanismName() Returns the IANA-registered mechanism name of this SASL server (e.g.
Object	getNegotiatedProperty(String propName) Retrieves the negotiated property.
boolean	isComplete() Determines if the authentication exchange has completed.
byte[]	unwrap(byte[] incoming, int offset, int len) Unwraps a byte array received from the client.
byte[]	wrap(byte[] outgoing, int offset, int len) Wraps a byte array to be sent to the client.

Method Detail

dispose

evaluateResponse

Evaluates the response data and generates a challenge. If a response is received from the client during the authentication process, this method is called to prepare an appropriate next challenge to submit to the client. The challenge is null if the authentication has succeeded and no more challenge data is to be sent to the client. It is non-null if the authentication must be continued by sending a challenge to the client, or if the authentication has succeeded but challenge data needs to be processed by the client. {@link #isComplete()} should be called after each call to evaluateResponse(),to determine if any further response is needed from the client.

Parameters: response the non-null (but possibly empty) response sent by the client.

Returns: the possibly null challenge to send to the client. It is null if the authentication has succeeded and there is no more challenge data to be sent to the client.

Throws: SaslException if an error occurred while processing the response or generating a challenge.

getAuthorizationID

getMechanismName

getNegotiatedProperty

Retrieves the negotiated property. This method can be called only after the authentication exchange has completed (i.e., when {@link #isComplete()} returns true); otherwise, an {@link IllegalStateException} is thrown.

Returns: the value of the negotiated property. If null, the property was not negotiated or is not applicable to this mechanism.

Throws: IllegalStateException if this authentication exchange has not completed.

isComplete

Determines if the authentication exchange has completed. This method is typically called after each invocation of {@link #evaluateResponse(byte[])} to determine whether the authentication has completed successfully or should be continued.

Returns: true if the authentication exchange has completed; false otherwise.

unwrap

Unwraps a byte array received from the client. This method can be called only after the authentication exchange has completed (i.e., when {@link #isComplete()} returns true) and only if the authentication exchange has negotiated integrity and/or privacy as the quality of protection; otherwise, an {@link IllegalStateException} is thrown.

incoming is the contents of the SASL buffer as defined in RFC 2222 without the leading four octet field that represents the length. offset and len specify the portion of incoming to use.

Parameters: incoming a non-null byte array containing the encoded bytes from the client. offset the starting position at incoming of the bytes to use. len the number of bytes from incoming to use.

Returns: a non-null byte array containing the decoded bytes.

Throws: SaslException if incoming cannot be successfully unwrapped. IllegalStateException if the authentication exchange has not completed, or if the negotiated quality of protection has neither integrity nor privacy.

wrap

Wraps a byte array to be sent to the client. This method can be called only after the authentication exchange has completed (i.e., when {@link #isComplete()} returns true) and only if the authentication exchange has negotiated integrity and/or privacy as the quality of protection; otherwise, an {@link IllegalStateException} is thrown.

The result of this method will make up the contents of the SASL buffer as defined in RFC 2222 without the leading four octet field that represents the length. offset and len specify the portion of outgoing to use.

Parameters: outgoing a non-null byte array containing the bytes to encode. offset the starting position at outgoing of the bytes to use. len the number of bytes from outgoing to use.

Returns: a non-null byte array containing the encoded bytes.

Throws: SaslException if outgoing cannot be successfully wrapped. IllegalStateException if the authentication exchange has not completed, or if the negotiated quality of protection has neither integrity nor privacy.

Interface SaslServer