RSA分段加密分段解密以及密钥与.Net的转化

代码中采用了Base64 对应的Maven仓库地址

<!-- http://mvnrepository.com/artifact/net.iharder/base64 --><dependency>    <groupId>net.iharder</groupId>    <artifactId>base64</artifactId>    <version>2.3.9</version></dependency>

Java源代码如下

package org.utils.code;import java.io.ByteArrayOutputStream;import java.io.IOException;import java.security.InvalidKeyException;import java.security.KeyFactory;import java.security.KeyPair;import java.security.KeyPairGenerator;import java.security.NoSuchAlgorithmException;import java.security.PrivateKey;import java.security.PublicKey;import java.security.interfaces.RSAPrivateCrtKey;import java.security.interfaces.RSAPrivateKey;import java.security.interfaces.RSAPublicKey;import java.security.spec.InvalidKeySpecException;import java.security.spec.PKCS8EncodedKeySpec;import java.security.spec.X509EncodedKeySpec;import java.util.HashMap;import java.util.Map;import javax.crypto.BadPaddingException;import javax.crypto.Cipher;import javax.crypto.IllegalBlockSizeException;import javax.crypto.NoSuchPaddingException;import net.iharder.Base64;public class RSAUtils {public static final String KEY_ALGORITHM = "RSA";private static final String PUBLIC_KEY = "publicKey";private static final String PRIVATE_KEY = "privateKey";/** * 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;/** * @Title: publicKeyToString * @Description: 得到字符串型的公钥 Java * @param publicKey * @return String */public static String publicKeyToString(RSAPublicKey publicKey) {return Base64.encodeBytes(publicKey.getEncoded());}/** * @Title: privateKeyToString * @Description: 得到字符串型的私钥 Java * @param privateKey * @return String */public static String privateKeyToString(RSAPrivateKey privateKey) {return Base64.encodeBytes(privateKey.getEncoded());}/** * @Title: getPublicKey * @Description: 将字符串型公钥转化为PublicKey Java * @param publicKey * @return PublicKey */public static PublicKey getPublicKey(String publicKey) {try {X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(Base64.decode(publicKey));KeyFactory factory;factory = KeyFactory.getInstance(KEY_ALGORITHM);return factory.generatePublic(x509EncodedKeySpec);} catch (NoSuchAlgorithmException e) {e.printStackTrace();} catch (InvalidKeySpecException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();}return null;}/** * @Title: getPrivateKey * @Description: 将字符串型私钥转化为 PrivateKey Java * @param privateKey * @return PrivateKey */public static PrivateKey getPrivateKey(String privateKey) {try {PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(Base64.decode(privateKey));KeyFactory factory = KeyFactory.getInstance(KEY_ALGORITHM);return factory.generatePrivate(pkcs8EncodedKeySpec);} catch (NoSuchAlgorithmException e) {e.printStackTrace();} catch (InvalidKeySpecException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();}return null;}/** * @Title: generateKeyBytes * @Description: 初始化密钥对 * @return Map<String,Object> */public static Map<String, Object> generateKeyBytes() {KeyPairGenerator keyPairGen;try {keyPairGen = KeyPairGenerator.getInstance(KEY_ALGORITHM);keyPairGen.initialize(1024);KeyPair keyPair = keyPairGen.generateKeyPair();RSAPublicKey publicKey = (RSAPublicKey) keyPair.getPublic();RSAPrivateKey privateKey = (RSAPrivateKey) keyPair.getPrivate();Map<String, Object> keyMap = new HashMap<String, Object>(2);keyMap.put(PUBLIC_KEY, publicKey);keyMap.put(PRIVATE_KEY, privateKey);return keyMap;} catch (NoSuchAlgorithmException e) {e.printStackTrace();}return null;}/** * @Title: RSAEncode * @Description: 将字符串加密 * @param key * @param plainText * @return String */public static String RSAEncode(PublicKey key, String plainText) {byte[] b = plainText.getBytes();try {int inputLen = b.length;ByteArrayOutputStream out = new ByteArrayOutputStream();int offSet = 0;byte[] cache;int i = 0;Cipher cipher = Cipher.getInstance(KEY_ALGORITHM);cipher.init(Cipher.ENCRYPT_MODE, key);// 对数据分段解密while (inputLen - offSet > 0) {if (inputLen - offSet > MAX_ENCRYPT_BLOCK) {cache = cipher.doFinal(b, offSet, MAX_ENCRYPT_BLOCK);} else {cache = cipher.doFinal(b, offSet, inputLen - offSet);}out.write(cache, 0, cache.length);i++;offSet = i * MAX_ENCRYPT_BLOCK;}byte[] decryptedData = out.toByteArray();out.close();return Base64.encodeBytes(decryptedData);} catch (InvalidKeyException | NoSuchAlgorithmException | NoSuchPaddingException | IllegalBlockSizeException| BadPaddingException | IOException e) {e.printStackTrace();}return null;}/** * @Title: RSADecode * @Description: 将字符串解密 * @param key * @param encodedText * @return String */public static String RSADecode(PrivateKey key, String encodedText) {try {byte[] b = Base64.decode(encodedText);int inputLen = b.length;ByteArrayOutputStream out = new ByteArrayOutputStream();int offSet = 0;byte[] cache;int i = 0;Cipher cipher = Cipher.getInstance(KEY_ALGORITHM);cipher.init(Cipher.DECRYPT_MODE, key);// 对数据分段解密while (inputLen - offSet > 0) {if (inputLen - offSet > MAX_DECRYPT_BLOCK) {cache = cipher.doFinal(b, offSet, MAX_DECRYPT_BLOCK);} else {cache = cipher.doFinal(b, offSet, inputLen - offSet);}out.write(cache, 0, cache.length);i++;offSet = i * MAX_DECRYPT_BLOCK;}byte[] decryptedData = out.toByteArray();out.close();return new String(decryptedData);} catch (NoSuchAlgorithmException | NoSuchPaddingException | InvalidKeyException | IllegalBlockSizeException| BadPaddingException | IOException e) {e.printStackTrace();}return null;}/** * @Title: getRSAPrivateKeyAsNetFormat * @Description: 将Java私钥转化为.Net格式 * @param privateKey * @return String */public static String getRSAPrivateKeyAsNetFormat(String privateKey) {try {StringBuffer buff = new StringBuffer(1024);PKCS8EncodedKeySpec pvkKeySpec = new PKCS8EncodedKeySpec(getPrivateKey(privateKey).getEncoded());KeyFactory keyFactory = KeyFactory.getInstance("RSA");RSAPrivateCrtKey pvkKey = (RSAPrivateCrtKey) keyFactory.generatePrivate(pvkKeySpec);buff.append("<RSAKeyValue>");buff.append("<Modulus>" + Base64.encodeBytes(removeMSZero(pvkKey.getModulus().toByteArray())) + "</Modulus>");buff.append("<Exponent>" + Base64.encodeBytes(removeMSZero(pvkKey.getPublicExponent().toByteArray()))+ "</Exponent>");buff.append("<P>" + Base64.encodeBytes(removeMSZero(pvkKey.getPrimeP().toByteArray())) + "</P>");buff.append("<Q>" + Base64.encodeBytes(removeMSZero(pvkKey.getPrimeQ().toByteArray())) + "</Q>");buff.append("<DP>" + Base64.encodeBytes(removeMSZero(pvkKey.getPrimeExponentP().toByteArray())) + "</DP>");buff.append("<DQ>" + Base64.encodeBytes(removeMSZero(pvkKey.getPrimeExponentQ().toByteArray())) + "</DQ>");buff.append("<InverseQ>" + Base64.encodeBytes(removeMSZero(pvkKey.getCrtCoefficient().toByteArray()))+ "</InverseQ>");buff.append("<D>" + Base64.encodeBytes(removeMSZero(pvkKey.getPrivateExponent().toByteArray())) + "</D>");buff.append("</RSAKeyValue>");return buff.toString();} catch (Exception e) {System.err.println(e);return null;}}/** * @Title: getRSAPublicKeyAsNetFormat * @Description: 将Java公钥转化为.Net格式 * @param encodedPublicKey * @return String */public static String getRSAPublicKeyAsNetFormat(String publicKey) {try {StringBuffer buff = new StringBuffer(1024);KeyFactory keyFactory = KeyFactory.getInstance("RSA");RSAPublicKey pukKey = (RSAPublicKey) keyFactory.generatePublic(new X509EncodedKeySpec(getPublicKey(publicKey).getEncoded()));buff.append("<RSAKeyValue>");buff.append("<Modulus>" + Base64.encodeBytes(removeMSZero(pukKey.getModulus().toByteArray())) + "</Modulus>");buff.append("<Exponent>" + Base64.encodeBytes(removeMSZero(pukKey.getPublicExponent().toByteArray()))+ "</Exponent>");buff.append("</RSAKeyValue>");return buff.toString();} catch (Exception e) {System.err.println(e);return null;}}/** * @Title: removeMSZero * @Description: JAVA和.Net密钥转化算法 * @param data * @return byte[] */private static byte[] removeMSZero(byte[] data) {byte[] temp;int len = data.length;if (data[0] == 0) {temp = new byte[data.length - 1];System.arraycopy(data, 1, temp, 0, len - 1);} elsetemp = data;return temp;}public static void main(String[] args) {Map<String, Object> map = generateKeyBytes();String publicKey = publicKeyToString((RSAPublicKey) map.get(PUBLIC_KEY));String privateKey = privateKeyToString((RSAPrivateKey) map.get(PRIVATE_KEY));System.out.println("生成的公钥Java--> " + publicKey);System.out.println("生成的公钥.Net--> " + getRSAPublicKeyAsNetFormat(publicKey));System.out.println("生成的私钥Java--> " + privateKey);System.out.println("生成的私钥.Net--> " + getRSAPrivateKeyAsNetFormat(privateKey));String dataText = "这是需要加密的数据,RSA加密明文长度为117字节 所以我这里采用了分段加密和分段解密";System.out.println("加密前--> " + dataText);String ciphertext = RSAEncode(getPublicKey(publicKey), dataText);System.out.println("加密后--> " + ciphertext);System.out.println("解密后--> " + RSADecode(getPrivateKey(privateKey), ciphertext));}}

闲暇时还写了个小工具 张这样需要的也可以下载 点击打开链接