package?BGN;

import?java.math.BigInteger;
import?java.security.SecureRandom;

import?it.unisa.dia.gas.jpbc.Element;
import?it.unisa.dia.gas.jpbc.Field;
import?it.unisa.dia.gas.jpbc.PairingParameters;
import?it.unisa.dia.gas.plaf.jpbc.pairing.a1.TypeA1CurveGenerator;
import?it.unisa.dia.gas.plaf.jpbc.pairing.a1.TypeA1Pairing;
import?it.unisa.dia.gas.plaf.jpbc.util.math.BigIntegerUtils;

public?class?BGNEncryption?{

	public?static?final?String?start?=?“start“;
	public?static?final?String?end?=?“end“;
	private?PairingParameters?param;
	private?BigInteger?r;
	private?BigInteger?q;?//?This?is?the?private?key.
	private?BigInteger?order;
	private?SecureRandom?rng;

	public?PublicKey?gen（int?bits）?{
		rng?=?new?SecureRandom（）;
		TypeA1CurveGenerator?a1?=?new?TypeA1CurveGenerator（rng?2?bits）;?//?Requires
																			//?2
																			//?prime
																			//?numbers.
		param?=?a1.generate（）;
		TypeA1Pairing?pairing?=?new?TypeA1Pairing（param）;
		order?=?param.getBigInteger（“n“）;?//?Must?extract?the?prime?numbers?for
											//?both?keys.
		r?=?param.getBigInteger（“n0“）;
		q?=?param.getBigInteger（“n1“）;
		Field?f?=?pairing.getG1（）;
		Element?P?=?f.newRandomElement（）;
		P?=?P.mul（param.getBigInteger（“l(fā)“））;
		Element?Q?=?f.newElement（）;
		Q?=?Q.set（P）;
		Q?=?Q.mul（r）;
		return?new?PublicKey（pairing?P?Q?order）;
	}

	public?Element?encrypt（PublicKey?PK?int?msg）?{
		BigInteger?t?=?BigIntegerUtils.getRandom（PK.getN（））;
		int?m?=?msg;
		System.out.println（“Hash?is?“?+?m）;
		Field?f?=?PK.getField（）;
		Element?A?=?f.newElement（）;
		Element?B?=?f.newElement（）;
		Element?C?=?f.newElement（）;
		A?=?A.set（PK.getP（））;
		A?=?A.mul（BigInteger.valueOf（m））;
		B?=?B.set（PK.getQ（））;
		B?=?B.mul（t）;
		C?=?C.set（A）;
		C?=?C.add（B）;
		return?C;
	}

	public?Element?add（PublicKey?PK?Element?A?Element?B）?{
		BigInteger?t?=?BigIntegerUtils.getRandom（PK.getN（））;
		Field?f?=?PK.getField（）;
		Element?output?=?f.newElement（）;
		Element?aux?=?f.newElement（）;
		aux.set（PK.getQ（））;
		aux.mul（t）;
		output.set（A）;
		output.add（B）;
		output.add（aux）;
		return?output;
	}

	public?Element?mul（PublicKey?PK?Element?C?Element?D）?{
		BigInteger?t?=?BigIntegerUtils.getRandom（PK.getN（））;

		Element?T?=?PK.doPairing（C?D）;

		Element?K?=?PK.doPairing（PK.getQ（）?PK.getQ（））;
		K?=?K.pow（t）;
		return?T.mul（K）;
	}

	public?String?decryptMul（PublicKey?PK?BigInteger?sk?Element?C）?{
		Element?PSK?=?PK.doPairing（PK.getP（）?PK.getP（））;
		PSK.pow（sk）;

		Element?CSK?=?C.duplicate（）;
		CSK.pow（sk）;
		Element?aux?=?PSK.duplicate（）;

		BigInteger?m?=?new?BigInteger（“1“）;
		while?（!aux.isEqual（CSK））?{
			aux?=?aux.mul（PSK）;
			m?=?m.add（BigInteger.valueOf（1））;
		}
		return?m.toString（）;
	}

	public?String?decrypt（PublicKey?PK?BigInteger?sk?Element?C）?{
		Field?f?=?PK.getField（）;
		Element?T?=?f.newElement（）;
		Element?K?=?f.newElement（）;
		Element?aux?=?f.newElement（）;
		T?=?

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----

?????文件????????988??2018-08-22?18:27??BGN\.classpath

?????文件????????379??2018-08-22?18:26??BGN\.project

?????文件????????598??2018-08-22?18:26??BGN\.settings\org.eclipse.jdt.core.prefs

?????文件???????5456??2018-08-22?18:27??BGN\bin\BGN\BGNEncryption.class

?????文件???????1579??2018-08-22?18:27??BGN\bin\BGN\PublicKey.class

?????文件???????2149??2018-08-22?18:27??BGN\bin\BGN\text.class

?????文件???????4455??2018-08-22?18:15??BGN\src\BGN\BGNEncryption.java

?????文件????????803??2018-08-21?18:09??BGN\src\BGN\PublicKey.java

?????文件???????1265??2018-08-22?16:49??BGN\src\BGN\text.java

?????目錄??????????0??2018-08-22?18:27??BGN\bin\BGN

?????目錄??????????0??2018-08-22?12:03??BGN\src\BGN

?????目錄??????????0??2018-08-22?18:26??BGN\.settings

?????目錄??????????0??2018-08-22?18:27??BGN\bin

?????目錄??????????0??2018-08-22?18:26??BGN\src

?????目錄??????????0??2018-08-22?18:26??BGN

-----------?---------??----------?-----??----

????????????????17672????????????????????15