com.google.crypto.tink.aead

Class XAesGcmParameters

java.lang.Object

com.google.crypto.tink.Parameters

com.google.crypto.tink.aead.AeadParameters

com.google.crypto.tink.aead.XAesGcmParameters

public final class XAesGcmParameters
extends AeadParameters

Describes the parameters of an XAesGcmKey

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	XAesGcmParameters.Variant Describes how the prefix is computed.

Method Summary

Modifier and Type	Method and Description
static XAesGcmParameters	create(XAesGcmParameters.Variant variant, int saltSizeBytes) Creates a new XAesGcmParameters object for generating new instances of XAesGcmKey.
boolean	equals(Object o)
int	getSaltSizeBytes()
XAesGcmParameters.Variant	getVariant() Returns a variant object.
int	hashCode()
boolean	hasIdRequirement() Returns true if a key created with the parameters in this object has to have a certain ID when it is in a keyset.
String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Method Detail

create

public static XAesGcmParameters create(XAesGcmParameters.Variant variant,
                                       int saltSizeBytes)
                                throws GeneralSecurityException

Creates a new XAesGcmParameters object for generating new instances of XAesGcmKey. The key size is 32 bytes and the tag size is 16 bytes. The IV size in bytes is saltSizeBytes + 12.

create(Variant.NO_PREFIX, 12) returns XAesGcmParameters that follow the XAES-256-GCM specification.

Parameters:

variant - the variant of the X-AES-GCM key.

saltSizeBytes - the size of the salt in bytes. Must be between 8 and 12 bytes.

Throws:

GeneralSecurityException

getVariant

public XAesGcmParameters.Variant getVariant()

Returns a variant object.

getSaltSizeBytes

public int getSaltSizeBytes()

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

hasIdRequirement

public boolean hasIdRequirement()

Description copied from class: Parameters

Returns true if a key created with the parameters in this object has to have a certain ID when it is in a keyset.

In Tink, certain keys change their behavior depending on the key id (for example, an Aead object can prefix the ciphertext with the big endian encoding of the key id). If this is the case, such a key should require a unique id in Key.getIdRequirementOrNull() and return true here.

Specified by:

hasIdRequirement in class Parameters

toString

public String toString()

Overrides:

toString in class Object