Mobile Agents

7.3 Extending Kalong  289

36 {

37 throw new MDLException( "signed data item was tampered with" );

38 }

39

40 try

41 {

42 return (Serializable)signedObject.getObject();

43 } catch( Exception e )

44 {

45 throw new MDLException( e );

46 }

47 }

48

49 // ...

50 }

Protect Data Items for a Target Agency

Finally, we present the code to encr ypt a data item so that it can be read only

at a single target agency. The agent calls this method to store a data item

under the given name, which is encrypted with the public key of the agency

whose local keystore alias is given in parameter targetAlias.

Data encr yption is done in Java using objects of class Cipher, and we

assume that an object with name rsaCipher has been initialized to use

asymmetric RSA encryption. In line 9