咸阳个人兼职网站建设,网站建设越来越便宜,株洲论坛网,松江网站建设博客该工具类中用到了BASE64#xff0c;需要借助第三方类库#xff1a;javabase64-1.3.1.jar注意#xff1a;RSA加密明文最大长度117字节#xff0c;解密要求密文最大长度为128字节#xff0c;所以在加密和解密的过程中需要分块进行。RSA加密对明文的长度是有限制的#xff0…该工具类中用到了BASE64需要借助第三方类库javabase64-1.3.1.jar注意RSA加密明文最大长度117字节解密要求密文最大长度为128字节所以在加密和解密的过程中需要分块进行。RSA加密对明文的长度是有限制的如果加密数据过大会抛出如下异常Exception in thread main javax.crypto.IllegalBlockSizeException: Data must not be longer than 117 bytesat com.sun.crypto.provider.RSACipher.a(DashoA13*..)at com.sun.crypto.provider.RSACipher.engineDoFinal(DashoA13*..)at javax.crypto.Cipher.doFinal(DashoA13*..)RSAUtils.javapackage security;import java.io.ByteArrayOutputStream;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.Signature;import java.security.interfaces.RSAPrivateKey;import java.security.interfaces.RSAPublicKey;import java.security.spec.PKCS8EncodedKeySpec;import java.security.spec.X509EncodedKeySpec;import java.util.HashMap;import java.util.Map;import javax.crypto.Cipher;/*** * RSA公钥/私钥/签名工具包* * * 罗纳德·李维斯特(Ron [R]ivest)、阿迪·萨莫尔(Adi [S]hamir)和伦纳德·阿德曼(Leonard [A]dleman)* * * 字符串格式的密钥在未在特殊说明情况下都为BASE64编码格式* 由于非对称加密速度极其缓慢一般文件不使用它来加密而是使用对称加密* 非对称加密算法可以用来对对称加密的密钥加密这样保证密钥的安全也就保证了数据的安全* ** author IceWee* date 2012-4-26* version 1.0*/public class RSAUtils {/*** 加密算法RSA*/public static final String KEY_ALGORITHM RSA;/*** 签名算法*/public static final String SIGNATURE_ALGORITHM MD5withRSA;/*** 获取公钥的key*/private static final String PUBLIC_KEY RSAPublicKey;/*** 获取私钥的key*/private static final String PRIVATE_KEY RSAPrivateKey;/*** RSA最大加密明文大小*/private static final int MAX_ENCRYPT_BLOCK 117;/*** RSA最大解密密文大小*/private static final int MAX_DECRYPT_BLOCK 128;/*** * 生成密钥对(公钥和私钥)* ** return* throws Exception*/public static Map genKeyPair() throws Exception {KeyPairGenerator keyPairGen KeyPairGenerator.getInstance(KEY_ALGORITHM);keyPairGen.initialize(1024);KeyPair keyPair keyPairGen.generateKeyPair();RSAPublicKey publicKey (RSAPublicKey) keyPair.getPublic();RSAPrivateKey privateKey (RSAPrivateKey) keyPair.getPrivate();Map keyMap new HashMap(2);keyMap.put(PUBLIC_KEY, publicKey);keyMap.put(PRIVATE_KEY, privateKey);return keyMap;}/*** * 用私钥对信息生成数字签名* ** param data 已加密数据* param privateKey 私钥(BASE64编码)** return* throws Exception*/public static String sign(byte[] data, String privateKey) throws Exception {byte[] keyBytes Base64Utils.decode(privateKey);PKCS8EncodedKeySpec pkcs8KeySpec new PKCS8EncodedKeySpec(keyBytes);KeyFactory keyFactory KeyFactory.getInstance(KEY_ALGORITHM);PrivateKey privateK keyFactory.generatePrivate(pkcs8KeySpec);Signature signature Signature.getInstance(SIGNATURE_ALGORITHM);signature.initSign(privateK);signature.update(data);return Base64Utils.encode(signature.sign());}/*** * 校验数字签名* ** param data 已加密数据* param publicKey 公钥(BASE64编码)* param sign 数字签名** return* throws Exception**/public static boolean verify(byte[] data, String publicKey, String sign)throws Exception {byte[] keyBytes Base64Utils.decode(publicKey);X509EncodedKeySpec keySpec new X509EncodedKeySpec(keyBytes);KeyFactory keyFactory KeyFactory.getInstance(KEY_ALGORITHM);PublicKey publicK keyFactory.generatePublic(keySpec);Signature signature Signature.getInstance(SIGNATURE_ALGORITHM);signature.initVerify(publicK);signature.update(data);return signature.verify(Base64Utils.decode(sign));}/*** * 私钥解密* ** param encryptedData 已加密数据* param privateKey 私钥(BASE64编码)* return* throws Exception*/public static byte[] decryptByPrivateKey(byte[] encryptedData, String privateKey)throws Exception {byte[] keyBytes Base64Utils.decode(privateKey);PKCS8EncodedKeySpec pkcs8KeySpec new PKCS8EncodedKeySpec(keyBytes);KeyFactory keyFactory KeyFactory.getInstance(KEY_ALGORITHM);Key privateK keyFactory.generatePrivate(pkcs8KeySpec);Cipher cipher Cipher.getInstance(keyFactory.getAlgorithm());cipher.init(Cipher.DECRYPT_MODE, privateK);int inputLen encryptedData.length;ByteArrayOutputStream out new ByteArrayOutputStream();int offSet 0;byte[] cache;int i 0;// 对数据分段解密while (inputLen - offSet 0) {if (inputLen - offSet MAX_DECRYPT_BLOCK) {cache cipher.doFinal(encryptedData, offSet, MAX_DECRYPT_BLOCK);} else {cache cipher.doFinal(encryptedData, offSet, inputLen - offSet);}out.write(cache, 0, cache.length);i;offSet i * MAX_DECRYPT_BLOCK;}byte[] decryptedData out.toByteArray();out.close();return decryptedData;}/*** * 公钥解密* ** param encryptedData 已加密数据* param publicKey 公钥(BASE64编码)* return* throws Exception*/public static byte[] decryptByPublicKey(byte[] encryptedData, String publicKey)throws Exception {byte[] keyBytes Base64Utils.decode(publicKey);X509EncodedKeySpec x509KeySpec new X509EncodedKeySpec(keyBytes);KeyFactory keyFactory KeyFactory.getInstance(KEY_ALGORITHM);Key publicK keyFactory.generatePublic(x509KeySpec);Cipher cipher Cipher.getInstance(keyFactory.getAlgorithm());cipher.init(Cipher.DECRYPT_MODE, publicK);int inputLen encryptedData.length;ByteArrayOutputStream out new ByteArrayOutputStream();int offSet 0;byte[] cache;int i 0;// 对数据分段解密while (inputLen - offSet 0) {if (inputLen - offSet MAX_DECRYPT_BLOCK) {cache cipher.doFinal(encryptedData, offSet, MAX_DECRYPT_BLOCK);} else {cache cipher.doFinal(encryptedData, offSet, inputLen - offSet);}out.write(cache, 0, cache.length);i;offSet i * MAX_DECRYPT_BLOCK;}byte[] decryptedData out.toByteArray();out.close();return decryptedData;}/*** * 公钥加密* ** param data 源数据* param publicKey 公钥(BASE64编码)* return* throws Exception*/public static byte[] encryptByPublicKey(byte[] data, String publicKey)throws Exception {byte[] keyBytes Base64Utils.decode(publicKey);X509EncodedKeySpec x509KeySpec new X509EncodedKeySpec(keyBytes);KeyFactory keyFactory KeyFactory.getInstance(KEY_ALGORITHM);Key publicK keyFactory.generatePublic(x509KeySpec);// 对数据加密Cipher cipher Cipher.getInstance(keyFactory.getAlgorithm());cipher.init(Cipher.ENCRYPT_MODE, publicK);int inputLen data.length;ByteArrayOutputStream out new ByteArrayOutputStream();int offSet 0;byte[] cache;int i 0;// 对数据分段加密while (inputLen - offSet 0) {if (inputLen - offSet MAX_ENCRYPT_BLOCK) {cache cipher.doFinal(data, offSet, MAX_ENCRYPT_BLOCK);} else {cache cipher.doFinal(data, offSet, inputLen - offSet);}out.write(cache, 0, cache.length);i;offSet i * MAX_ENCRYPT_BLOCK;}byte[] encryptedData out.toByteArray();out.close();return encryptedData;}/*** * 私钥加密* ** param data 源数据* param privateKey 私钥(BASE64编码)* return* throws Exception*/public static byte[] encryptByPrivateKey(byte[] data, String privateKey)throws Exception {byte[] keyBytes Base64Utils.decode(privateKey);PKCS8EncodedKeySpec pkcs8KeySpec new PKCS8EncodedKeySpec(keyBytes);KeyFactory keyFactory KeyFactory.getInstance(KEY_ALGORITHM);Key privateK keyFactory.generatePrivate(pkcs8KeySpec);Cipher cipher Cipher.getInstance(keyFactory.getAlgorithm());cipher.init(Cipher.ENCRYPT_MODE, privateK);int inputLen data.length;ByteArrayOutputStream out new ByteArrayOutputStream();int offSet 0;byte[] cache;int i 0;// 对数据分段加密while (inputLen - offSet 0) {if (inputLen - offSet MAX_ENCRYPT_BLOCK) {cache cipher.doFinal(data, offSet, MAX_ENCRYPT_BLOCK);} else {cache cipher.doFinal(data, offSet, inputLen - offSet);}out.write(cache, 0, cache.length);i;offSet i * MAX_ENCRYPT_BLOCK;}byte[] encryptedData out.toByteArray();out.close();return encryptedData;}/*** * 获取私钥* ** param keyMap 密钥对* return* throws Exception*/public static String getPrivateKey(Map keyMap)throws Exception {Key key (Key) keyMap.get(PRIVATE_KEY);return Base64Utils.encode(key.getEncoded());}/*** * 获取公钥* ** param keyMap 密钥对* return* throws Exception*/public static String getPublicKey(Map keyMap)throws Exception {Key key (Key) keyMap.get(PUBLIC_KEY);return Base64Utils.encode(key.getEncoded());}}Base64Utils.javaimport java.io.ByteArrayInputStream;import java.io.ByteArrayOutputStream;import java.io.File;import java.io.FileInputStream;import java.io.FileOutputStream;import java.io.InputStream;import java.io.OutputStream;import it.sauronsoftware.base64.Base64;/*** * BASE64编码解码工具包* * * 依赖javabase64-1.3.1.jar* ** author IceWee* date 2012-5-19* version 1.0*/public class Base64Utils {/*** 文件读取缓冲区大小*/private static final int CACHE_SIZE 1024;/*** * BASE64字符串解码为二进制数据* ** param base64* return* throws Exception*/public static byte[] decode(String base64) throws Exception {return Base64.decode(base64.getBytes());}/*** * 二进制数据编码为BASE64字符串* ** param bytes* return* throws Exception*/public static String encode(byte[] bytes) throws Exception {return new String(Base64.encode(bytes));}/*** * 将文件编码为BASE64字符串* * * 大文件慎用可能会导致内存溢出* ** param filePath 文件绝对路径* return* throws Exception*/public static String encodeFile(String filePath) throws Exception {byte[] bytes fileToByte(filePath);return encode(bytes);}/*** * BASE64字符串转回文件* ** param filePath 文件绝对路径* param base64 编码字符串* throws Exception*/public static void decodeToFile(String filePath, String base64) throws Exception {byte[] bytes decode(base64);byteArrayToFile(bytes, filePath);}/*** * 文件转换为二进制数组* ** param filePath 文件路径* return* throws Exception*/public static byte[] fileToByte(String filePath) throws Exception {byte[] data new byte[0];File file new File(filePath);if (file.exists()) {FileInputStream in new FileInputStream(file);ByteArrayOutputStream out new ByteArrayOutputStream(2048);byte[] cache new byte[CACHE_SIZE];int nRead 0;while ((nRead in.read(cache)) ! -1) {out.write(cache, 0, nRead);out.flush();}out.close();in.close();data out.toByteArray();}return data;}/*** * 二进制数据写文件* ** param bytes 二进制数据* param filePath 文件生成目录*/public static void byteArrayToFile(byte[] bytes, String filePath) throws Exception {InputStream in new ByteArrayInputStream(bytes);File destFile new File(filePath);if (!destFile.getParentFile().exists()) {destFile.getParentFile().mkdirs();}destFile.createNewFile();OutputStream out new FileOutputStream(destFile);byte[] cache new byte[CACHE_SIZE];int nRead 0;while ((nRead in.read(cache)) ! -1) {out.write(cache, 0, nRead);out.flush();}out.close();in.close();}}RSATester.javaimport java.util.Map;public class RSATester {static String publicKey;static String privateKey;static {try {Map keyMap RSAUtils.genKeyPair();publicKey RSAUtils.getPublicKey(keyMap);privateKey RSAUtils.getPrivateKey(keyMap);System.err.println(公钥: \n\r publicKey);System.err.println(私钥 \n\r privateKey);} catch (Exception e) {e.printStackTrace();}}public static void main(String[] args) throws Exception {test();testSign();}static void test() throws Exception {System.err.println(公钥加密——私钥解密);String source 这是一行没有任何意义的文字你看完了等于没看不是吗;System.out.println(\r加密前文字\r\n source);byte[] data source.getBytes();byte[] encodedData RSAUtils.encryptByPublicKey(data, publicKey);System.out.println(加密后文字\r\n new String(encodedData));byte[] decodedData RSAUtils.decryptByPrivateKey(encodedData, privateKey);String target new String(decodedData);System.out.println(解密后文字: \r\n target);}static void testSign() throws Exception {System.err.println(私钥加密——公钥解密);String source 这是一行测试RSA数字签名的无意义文字;System.out.println(原文字\r\n source);byte[] data source.getBytes();byte[] encodedData RSAUtils.encryptByPrivateKey(data, privateKey);System.out.println(加密后\r\n new String(encodedData));byte[] decodedData RSAUtils.decryptByPublicKey(encodedData, publicKey);String target new String(decodedData);System.out.println(解密后: \r\n target);System.err.println(私钥签名——公钥验证签名);String sign RSAUtils.sign(encodedData, privateKey);System.err.println(签名:\r sign);boolean status RSAUtils.verify(encodedData, publicKey, sign);System.err.println(验证结果:\r status);}}
