javax.crypto.ExemptionMechanism — clojure-interop/javax.crypto 1.0.2

This class provides the functionality of an exemption mechanism, examples of which are key recovery, key weakening, and key escrow.

Applications or applets that use an exemption mechanism may be granted stronger encryption capabilities than those which don't.

*get-instance clj

(*get-instance algorithm)

(*get-instance algorithm provider)

Returns an ExemptionMechanism object that implements the specified exemption mechanism algorithm.

A new ExemptionMechanism object encapsulating the ExemptionMechanismSpi implementation from the specified provider is returned. The specified provider must be registered in the security provider list.

Note that the list of registered providers may be retrieved via the Security.getProviders() method.

algorithm - the standard name of the requested exemption mechanism. See the ExemptionMechanism section in the Java Cryptography Architecture Standard Algorithm Name Documentation for information about standard exemption mechanism names. - java.lang.String provider - the name of the provider. - java.lang.String

returns: the new ExemptionMechanism object. - javax.crypto.ExemptionMechanism

throws: java.lang.NullPointerException - if algorithm is null.

crypto-allowed? clj

(crypto-allowed? this key)

Returns whether the result blob has been generated successfully by this exemption mechanism.

The method also makes sure that the key passed in is the same as the one this exemption mechanism used in initializing and generating phases.

key - the key the crypto is going to use. - java.security.Key

returns: whether the result blob of the same key has been generated successfully by this exemption mechanism; false if key is null. - boolean

throws: javax.crypto.ExemptionMechanismException - if problem(s) encountered while determining whether the result blob has been generated successfully by this exemption mechanism object.

gen-exemption-blob clj

(gen-exemption-blob this)

(gen-exemption-blob this output)

(gen-exemption-blob this output output-offset)

Generates the exemption mechanism key blob, and stores the result in the output buffer, starting at outputOffset inclusive.

If the output buffer is too small to hold the result, a ShortBufferException is thrown. In this case, repeat this call with a larger output buffer. Use getOutputSize to determine how big the output buffer should be.

output - the buffer for the result - byte[] output-offset - the offset in output where the result is stored - int

returns: the number of bytes stored in output - int

throws: java.lang.IllegalStateException - if this exemption mechanism is in a wrong state (e.g., has not been initialized).

get-name clj

(get-name this)

Returns the exemption mechanism name of this ExemptionMechanism object.

This is the same name that was specified in one of the getInstance calls that created this ExemptionMechanism object.

returns: the exemption mechanism name of this ExemptionMechanism object. - java.lang.String

get-output-size clj

(get-output-size this input-len)

Returns the length in bytes that an output buffer would need to be in order to hold the result of the next genExemptionBlob operation, given the input length inputLen (in bytes).

The actual output length of the next genExemptionBlob call may be smaller than the length returned by this method.

input-len - the input length (in bytes) - int

returns: the required output buffer size (in bytes) - int

throws: java.lang.IllegalStateException - if this exemption mechanism is in a wrong state (e.g., has not yet been initialized)

get-provider clj

(get-provider this)

Returns the provider of this ExemptionMechanism object.

returns: the provider of this ExemptionMechanism object. - java.security.Provider

init clj

(init this key)

(init this key params)

Initializes this exemption mechanism with a key and a set of algorithm parameters.

If this exemption mechanism requires any algorithm parameters and params is null, the underlying exemption mechanism implementation is supposed to generate the required parameters itself (using provider-specific default values); in the case that algorithm parameters must be specified by the caller, an InvalidAlgorithmParameterException is raised.

key - the key for this exemption mechanism - java.security.Key params - the algorithm parameters - java.security.spec.AlgorithmParameterSpec

throws: java.security.InvalidKeyException - if the given key is inappropriate for this exemption mechanism.