具有短密文的秘密密钥匿名IBE

Question

我正在尝试使用JPBC的短密文实现完全安全的匿名HIBE和秘密密钥匿名IBE。看起来代码正在生成密文，但解密时会出现一些错误。

这是我的代码

import it.unisa.dia.gas.crypto.jpbc.fe.ibe.dip10.engines.AHIBEDIP10KEMEngine;
import it.unisa.dia.gas.crypto.jpbc.fe.ibe.dip10.generators.AHIBEDIP10KeyPairGenerator;
import it.unisa.dia.gas.crypto.jpbc.fe.ibe.dip10.generators.AHIBEDIP10SecretKeyGenerator;
import it.unisa.dia.gas.crypto.jpbc.fe.ibe.dip10.params.*;
import it.unisa.dia.gas.crypto.kem.KeyEncapsulationMechanism;
import it.unisa.dia.gas.jpbc.Element;
import it.unisa.dia.gas.jpbc.Pairing;
import it.unisa.dia.gas.plaf.jpbc.pairing.PairingFactory;
import org.bouncycastle.crypto.AsymmetricCipherKeyPair;
import org.bouncycastle.crypto.CipherParameters;
import org.bouncycastle.crypto.InvalidCipherTextException;

import java.util.Arrays;

import static org.junit.Assert.*;

public class AHIBEDIP10 {

public AHIBEDIP10() {
}

public AsymmetricCipherKeyPair setup(int bitLength, int length) {
    AHIBEDIP10KeyPairGenerator setup = new AHIBEDIP10KeyPairGenerator();
    setup.init(new AHIBEDIP10KeyPairGenerationParameters(bitLength, length));

    return setup.generateKeyPair();
}

public Element[] map(CipherParameters publicKey, String... ids) {
    Pairing pairing = PairingFactory
            .getPairing(((AHIBEDIP10PublicKeyParameters) publicKey)
                    .getParameters());

    Element[] elements = new Element[ids.length];
    for (int i = 0; i < elements.length; i++) {
        byte[] id = ids[i].getBytes();
        elements[i] = pairing.getZr().newElementFromHash(id, 0, id.length);
    }
    return elements;
}

public CipherParameters keyGen(AsymmetricCipherKeyPair masterKey,
        Element... ids) {
    AHIBEDIP10SecretKeyGenerator generator = new AHIBEDIP10SecretKeyGenerator();
    generator.init(new AHIBEDIP10SecretKeyGenerationParameters(
            (AHIBEDIP10MasterSecretKeyParameters) masterKey.getPrivate(),
            (AHIBEDIP10PublicKeyParameters) masterKey.getPublic(), ids));

    return generator.generateKey();
}

public CipherParameters delegate(AsymmetricCipherKeyPair masterKey,
        CipherParameters secretKey, Element id) {
    AHIBEDIP10SecretKeyGenerator generator = new AHIBEDIP10SecretKeyGenerator();
    generator.init(new AHIBEDIP10DelegateGenerationParameters(
            (AHIBEDIP10PublicKeyParameters) masterKey.getPublic(),
            (AHIBEDIP10SecretKeyParameters) secretKey, id));

    return generator.generateKey();
}

public byte[][] encaps(CipherParameters publicKey, Element... ids) {
    try {
        KeyEncapsulationMechanism kem = new AHIBEDIP10KEMEngine();
        kem.init(true, new AHIBEDIP10EncryptionParameters(
                (AHIBEDIP10PublicKeyParameters) publicKey, ids));

        byte[] ciphertext = kem.process();

        assertNotNull(ciphertext);
        assertNotSame(0, ciphertext.length);

        byte[] key = Arrays.copyOfRange(ciphertext, 0,
                kem.getKeyBlockSize());
        byte[] ct = Arrays.copyOfRange(ciphertext, kem.getKeyBlockSize(),
                ciphertext.length);

        return new byte[][] { key, ct };
    } catch (InvalidCipherTextException e) {
        e.printStackTrace();
        fail(e.getMessage());
    }
    return null;
}

public byte[] decaps(CipherParameters secretKey, byte[] cipherText) {
    try {
        KeyEncapsulationMechanism kem = new AHIBEDIP10KEMEngine();

        kem.init(false, secretKey);
        byte[] key = kem.processBlock(cipherText);

        assertNotNull(key);
        assertNotSame(0, key.length);

        return key;
    } catch (InvalidCipherTextException e) {
        e.printStackTrace();
        fail(e.getMessage());
    }

    return null;
}

public static void main(String[] args) {
    AHIBEDIP10 engine = new AHIBEDIP10();

    // Setup
    AsymmetricCipherKeyPair keyPair = engine.setup(64, 3);

    // KeyGen
    Element[] ids = engine.map(keyPair.getPublic(), "angelo", "de caro",
            "unisa");

    CipherParameters sk0 = engine.keyGen(keyPair, ids[0]);
    CipherParameters sk01 = engine.keyGen(keyPair, ids[0], ids[1]);
    CipherParameters sk012 = engine.keyGen(keyPair, ids[0], ids[1], ids[2]);

    CipherParameters sk1 = engine.keyGen(keyPair, ids[1]);
    CipherParameters sk10 = engine.keyGen(keyPair, ids[1], ids[0]);
    CipherParameters sk021 = engine.keyGen(keyPair, ids[0], ids[2], ids[1]);

    // Encryption/Decryption
    byte[][] ciphertext0 = engine.encaps(keyPair.getPublic(), ids[0]);

    byte[][] ciphertext01 = engine.encaps(keyPair.getPublic(), ids[0],
            ids[1]);
    byte[][] ciphertext012 = engine.encaps(keyPair.getPublic(), ids[0],
            ids[1], ids[2]);

    // Decrypt
    assertEquals(
            true,
            Arrays.equals(ciphertext0[0],
                    engine.decaps(sk0, ciphertext0[1])));
    assertEquals(
            true,
            Arrays.equals(ciphertext01[0],
                    engine.decaps(sk01, ciphertext01[1])));
    assertEquals(
            true,
            Arrays.equals(ciphertext012[0],
                    engine.decaps(sk012, ciphertext012[1])));

    assertEquals(
            false,
            Arrays.equals(ciphertext0[0],
                    engine.decaps(sk1, ciphertext0[1])));
    assertEquals(
            false,
            Arrays.equals(ciphertext01[0],
                    engine.decaps(sk10, ciphertext01[1])));
    assertEquals(
            false,
            Arrays.equals(ciphertext012[0],
                    engine.decaps(sk021, ciphertext012[1])));

    // Delegate/Decrypt
    assertEquals(true, Arrays.equals(ciphertext01[0], engine.decaps(
            engine.delegate(keyPair, sk0, ids[1]), ciphertext01[1])));
    assertEquals(true, Arrays.equals(ciphertext012[0], engine.decaps(
            engine.delegate(keyPair, sk01, ids[2]), ciphertext012[1])));
    assertEquals(true, Arrays.equals(ciphertext012[0], engine.decaps(engine
            .delegate(keyPair, engine.delegate(keyPair, sk0, ids[1]),
                    ids[2]), ciphertext012[1])));

    assertEquals(false, Arrays.equals(ciphertext01[0], engine.decaps(
            engine.delegate(keyPair, sk0, ids[0]), ciphertext01[1])));
    assertEquals(false, Arrays.equals(ciphertext012[0], engine.decaps(
            engine.delegate(keyPair, sk01, ids[1]), ciphertext012[1])));
    assertEquals(false, Arrays.equals(ciphertext012[0], engine.decaps(
            engine.delegate(keyPair, engine.delegate(keyPair, sk0, ids[2]),
                    ids[1]), ciphertext012[1])));
}

}

但我得到了DataLengthException

Exception in thread "main" org.bouncycastle.crypto.DataLengthException: Input too small for the cipher.
at it.unisa.dia.gas.crypto.jpbc.cipher.PairingAsymmetricBlockCipher.processBlock(PairingAsymmetricBlockCipher.java:86)
at it.unisa.dia.gas.crypto.jpbc.kem.PairingKeyEncapsulationMechanism.processBlock(PairingKeyEncapsulationMechanism.java:37)
at com.CAM.branching.AHIBEDIP10.decaps(AHIBEDIP10.java:96)
at com.CAM.branching.AHIBEDIP10.main(AHIBEDIP10.java:140)