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

This class provides the functionality of a key agreement (or key exchange) protocol.

The keys involved in establishing a shared secret are created by one of the key generators (KeyPairGenerator or KeyGenerator), a KeyFactory, or as a result from an intermediate phase of the key agreement protocol.

For each of the correspondents in the key exchange, doPhase needs to be called. For example, if this key exchange is with one other party, doPhase needs to be called once, with the lastPhase flag set to true. If this key exchange is with two other parties, doPhase needs to be called twice, the first time setting the lastPhase flag to false, and the second time setting it to true. There may be any number of parties involved in a key exchange.

Every implementation of the Java platform is required to support the following standard KeyAgreement algorithm:

DiffieHellman

This algorithm is described in the KeyAgreement section of the Java Cryptography Architecture Standard Algorithm Name Documentation. Consult the release documentation for your implementation to see if any other algorithms are supported.

*get-instance clj

(*get-instance algorithm)

(*get-instance algorithm provider)

Returns a KeyAgreement object that implements the specified key agreement algorithm.

A new KeyAgreement object encapsulating the KeyAgreementSpi 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 key agreement algorithm. See the KeyAgreement section in the Java Cryptography Architecture Standard Algorithm Name Documentation for information about standard algorithm names. - java.lang.String provider - the name of the provider. - java.lang.String

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

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

do-phase clj

(do-phase this key last-phase)

Executes the next phase of this key agreement with the given key that was received from one of the other parties involved in this key agreement.

key - the key for this phase. For example, in the case of Diffie-Hellman between 2 parties, this would be the other party's Diffie-Hellman public key. - java.security.Key last-phase - flag which indicates whether or not this is the last phase of this key agreement. - boolean

returns: the (intermediate) key resulting from this phase, or null if this phase does not yield a key - java.security.Key

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

generate-secret clj

(generate-secret this)

(generate-secret this algorithm)

(generate-secret this shared-secret offset)

Generates the shared secret, and places it into the buffer sharedSecret, beginning at offset inclusive.

If the sharedSecret buffer is too small to hold the result, a ShortBufferException is thrown. In this case, this call should be repeated with a larger output buffer.

This method resets this KeyAgreement object, so that it can be reused for further key agreements. Unless this key agreement is reinitialized with one of the init methods, the same private information and algorithm parameters will be used for subsequent key agreements.

shared-secret - the buffer for the shared secret - byte[] offset - the offset in sharedSecret where the shared secret will be stored - int

returns: the number of bytes placed into sharedSecret - int

throws: java.lang.IllegalStateException - if this key agreement has not been completed yet

get-algorithm clj

(get-algorithm this)

Returns the algorithm name of this KeyAgreement object.

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

returns: the algorithm name of this KeyAgreement object. - java.lang.String

get-provider clj

(get-provider this)

Returns the provider of this KeyAgreement object.

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

init clj

(init this key)

(init this key random)

(init this key params random)

Initializes this key agreement with the given key, set of algorithm parameters, and source of randomness.

key - the party's private information. For example, in the case of the Diffie-Hellman key agreement, this would be the party's own Diffie-Hellman private key. - java.security.Key params - the key agreement parameters - java.security.spec.AlgorithmParameterSpec random - the source of randomness - java.security.SecureRandom

throws: java.security.InvalidKeyException - if the given key is inappropriate for this key agreement, e.g., is of the wrong type or has an incompatible algorithm type.