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javax.crypto.spec
public class: GCMParameterSpec [javadoc | source]
java.lang.Object
   javax.crypto.spec.GCMParameterSpec

All Implemented Interfaces:
    AlgorithmParameterSpec

Specifies the set of parameters required by a javax.crypto.Cipher using the Galois/Counter Mode (GCM) mode.

Simple block cipher modes (such as CBC) generally require only an initialization vector (such as {@code IvParameterSpec}), but GCM needs these parameters:

In addition to the parameters described here, other GCM inputs/output (Additional Authenticated Data (AAD), Keys, block ciphers, plain/ciphertext and authentication tags) are handled in the {@code Cipher} class.

Please see RFC 5116 for more information on the Authenticated Encryption with Associated Data (AEAD) algorithm, and NIST Special Publication 800-38D, "NIST Recommendation for Block Cipher Modes of Operation: Galois/Counter Mode (GCM) and GMAC."

The GCM specification states that {@code tLen} may only have the values {128, 120, 112, 104, 96}, or {64, 32} for certain applications. Other values can be specified for this class, but not all CSP implementations will support them.

Constructor:
 public GCMParameterSpec(int tLen,
    byte[] src) 
 public GCMParameterSpec(int tLen,
    byte[] src,
    int offset,
    int len) 
Method from javax.crypto.spec.GCMParameterSpec Summary:
getIV,   getTLen
Methods from java.lang.Object:
clone,   equals,   finalize,   getClass,   hashCode,   notify,   notifyAll,   toString,   wait,   wait,   wait
Method from javax.crypto.spec.GCMParameterSpec Detail:
 public byte[] getIV() 
    Returns the Initialization Vector (IV).
 public int getTLen() 
    Returns the authentication tag length.