签名算法验证

5.DSS签名算法验证package DSS;import java.io.BufferedReader;import java.io.FileInputStream;import java.io.FileOutputStream;import java.io.InputStreamReader;import java.io.OutputStreamWriter;import java.security.Key; import java.security.KeyFactory; import java.security.KeyPair; import java.security.KeyPairGenerator; import java.security.PrivateKey; import java.security.PublicKey; import java.security.SecureRandom; import java.security.Signature; import java.security.spec.PKCS8EncodedKeySpec; import java.security.spec.X509EncodedKeySpec; import java.util.HashMap; import java.util.Map; import sun.misc.BASE64Decoder; import sun.misc.BASE64Encoder; public class DSS_Demo /不仅可以使用DSA算法，同样也可以使用RSA算法做数字签名 /*public static final String KEY_ALGORITHM = RSA; public static final String SIGNATURE_ALGORITHM = MD5withRSA;*/ public static final String KEY_ALGORITHM = DSA; public static final String SIGNATURE_ALGORITHM = DSA; public static final String DEFAULT_SEED = $%*%()(HJG8awfjas7; /默认种子 public static final String PUBLIC_KEY = DSAPublicKey; public static final String PRIVATE_KEY = DSAPrivateKey; public static void main(String args) throws Exception BufferedReader plain=new BufferedReader(new InputStreamReader(new FileInputStream(C:UsersAdministratorworkspaceCryptologysrcDSSplaintext.text); String str ; while(str=plain.readLine()!=null) byte data = str.getBytes(); Map keyMap = initKey();/ 构建密钥 PublicKey publicKey = (PublicKey) keyMap.get(PUBLIC_KEY); PrivateKey privateKey = (PrivateKey) keyMap.get(PRIVATE_KEY); System.out.println(私钥format： + privateKey.getFormat(); System.out.println(公钥format： + publicKey.getFormat(); / 产生签名 String sign = sign(data, getPrivateKey(keyMap); / 验证签名 boolean verify1 = verify(aaa.getBytes(), getPublicKey(keyMap), sign); System.err.println(经验证 数据和签名匹配: + verify1); boolean verify = verify(data, getPublicKey(keyMap), sign); System.err.println(经验证 数据和签名匹配: +verify); / System.out.println(数字签名为 +sign); OutputStreamWriter result=new OutputStreamWriter(new FileOutputStream(C:UsersAdministratorworkspaceCryptologysrcDSSsign.text); result.write(sign); result.close(); /* * 生成密钥 * param seed 种子 * return 密钥对象 * throws Exception */ public static Map initKey(String seed) throws Exception System.out.println(生成密钥); KeyPairGenerator keygen = KeyPairGenerator.getInstance(KEY_ALGORITHM); SecureRandom secureRandom = new SecureRandom(); secureRandom.setSeed(seed.getBytes(); /Modulus size must range from 512 to 1024 and be a multiple of 64 keygen.initialize(640, secureRandom); KeyPair keys = keygen.genKeyPair(); PrivateKey privateKey = keys.getPrivate(); PublicKey publicKey = keys.getPublic(); Map map = new HashMap(2); map.put(PUBLIC_KEY, publicKey); map.put(PRIVATE_KEY, privateKey); return map; /* * 生成默认密钥 * * return 密钥对象 * throws Exception */ public static Map initKey() throws Exception return initKey(DEFAULT_SEED); /* * 取得私钥 * param keyMap * return * throws Exception */ public static String getPrivateKey(Map keyMap) throws Exception Key key = (Key) keyMap.get(PRIVATE_KEY); return encryptBASE64(key.getEncoded(); /base64加密私钥 /* * 取得公钥 * param keyMap * return * throws Exception */ public static String getPublicKey(Map keyMap) throws Exception Key key = (Key) keyMap.get(PUBLIC_KEY); return encryptBASE64(key.getEncoded(); /base64加密公钥 /* * 用私钥对信息进行数字签名 * param data 加密数据 * param privateKey 私钥-base64加密的 * return * throws Exception */ public static String sign(byte data, String privateKey) throws Exception System.out.println(用私钥对信息进行数字签名); byte keyBytes = decryptBASE64(privateKey); PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(keyBytes); KeyFactory factory = KeyFactory.getInstance(KEY_ALGORITHM); PrivateKey priKey = factory.generatePrivate(keySpec);/生成 私钥 /用私钥对信息进行数字签名 Signature signature = Signature.getInstance(SIGNATURE_ALGORITHM); signature.initSign(priKey); signature.update(data); return encryptBASE64(signature.sign(); /* * BASE64Encoder 加密 * param data 要加密的数据 * return 加密后的字符串 */ private static String encryptBASE64(byte data) BASE64Encoder encoder = new BASE64Encoder(); String encode = encoder.encode(data); return encode; private static byte decryptBASE64(String data) throws Exception BASE64Decoder decoder = new BASE64Decoder(); byte buffer = decoder.decodeBuffer(data); return buffer; public static boolean verify(byte data, String publicKey, String sign) throws Exception byte keyBytes = decryptBASE64(publicKey); X509EncodedKeySpec keySpec = new X509EncodedKeySpec(keyBytes); KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORIT