RSA 加解密工具类,生成的公私钥配置到配置文件中这里使用 Nacos ,使用时直接使用@Value注解注入,调用加解密,工具类即可
package com.hkdw.datacenter.config.utils; import java.security.KeyFactory; import java.security.KeyPair; import java.security.KeyPairGenerator; import java.security.NoSuchAlgorithmException; 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 javax.crypto.Cipher; import org.springframework.util.Base64Utils; public class RSAUtils { /** * 生成公钥和私钥 */ public static HashMap<String, String> getKeys() throws NoSuchAlgorithmException { HashMap<String, String> map = new HashMap<>(); KeyPairGenerator keyPairGen = KeyPairGenerator.getInstance("RSA"); keyPairGen.initialize(1024); KeyPair keyPair = keyPairGen.generateKeyPair(); RSAPublicKey publicKey = (RSAPublicKey) keyPair.getPublic(); RSAPrivateKey privateKey = (RSAPrivateKey) keyPair.getPrivate(); map.put("public", Base64Utils.encodeToString(publicKey.getEncoded())); map.put("private", Base64Utils.encodeToString(privateKey.getEncoded())); return map; } /** * 得到公钥 * * @param publicKey 密钥字符串（经过base64编码） */ public static RSAPublicKey getPublicKey(String publicKey) throws NoSuchAlgorithmException, InvalidKeySpecException { //通过X509编码的Key指令获得公钥对象 KeyFactory keyFactory = KeyFactory.getInstance("RSA"); X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(Base64Utils.decodeFromString(publicKey)); return (RSAPublicKey) keyFactory.generatePublic(x509KeySpec); } /** * 得到私钥 * * @param privateKey 密钥字符串（经过base64编码） */ public static RSAPrivateKey getPrivateKey(String privateKey) throws NoSuchAlgorithmException, InvalidKeySpecException { //通过PKCS#8编码的Key指令获得私钥对象 KeyFactory keyFactory = KeyFactory.getInstance("RSA"); PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(Base64Utils.decodeFromString(privateKey)); return (RSAPrivateKey) keyFactory.generatePrivate(pkcs8KeySpec); } /** * 公钥加密 */ public static String encryptByPublicKey(String data, RSAPublicKey publicKey) throws Exception { Cipher cipher = Cipher.getInstance("RSA"); cipher.init(Cipher.ENCRYPT_MODE, publicKey); // 模长 int key_len = publicKey.getModulus().bitLength() / 8; // 加密数据长度 <= 模长-11 String[] datas = splitString(data, key_len - 11); String mi = ""; //如果明文长度大于模长-11则要分组加密 for (String s : datas) { mi += bcd2Str(cipher.doFinal(s.getBytes())); } return mi; } /** * 私钥解密 */ public static String decryptByPrivateKey(String data, RSAPrivateKey privateKey) throws Exception { Cipher cipher = Cipher.getInstance("RSA"); cipher.init(Cipher.DECRYPT_MODE, privateKey); //模长 int key_len = privateKey.getModulus().bitLength() / 8; byte[] bytes = data.getBytes(); byte[] bcd = ASCII_To_BCD(bytes, bytes.length); System.err.println(bcd.length); //如果密文长度大于模长则要分组解密 String ming = ""; byte[][] arrays = splitArray(bcd, key_len); for (byte[] arr : arrays) { ming += new String(cipher.doFinal(arr)); } return ming; } /** * ASCII码转BCD码 */ public static byte[] ASCII_To_BCD(byte[] ascii, int asc_len) { byte[] bcd = new byte[asc_len / 2]; int j = 0; for (int i = 0; i < (asc_len + 1) / 2; i++) { bcd[i] = asc_to_bcd(ascii[j++]); bcd[i] = (byte) (((j >= asc_len) ? 0x00 : asc_to_bcd(ascii[j++])) + (bcd[i] << 4)); } return bcd; } public static byte asc_to_bcd(byte asc) { byte bcd; if ((asc >= '0') && (asc <= '9')) { bcd = (byte) (asc - '0'); } else if ((asc >= 'A') && (asc <= 'F')) { bcd = (byte) (asc - 'A' + 10); } else if ((asc >= 'a') && (asc <= 'f')) { bcd = (byte) (asc - 'a' + 10); } else { bcd = (byte) (asc - 48); } return bcd; } /** * BCD转字符串 */ public static String bcd2Str(byte[] bytes) { char temp[] = new char[bytes.length * 2], val; for (int i = 0; i < bytes.length; i++) { val = (char) (((bytes[i] & 0xf0) >> 4) & 0x0f); temp[i * 2] = (char) (val > 9 ? val + 'A' - 10 : val + '0'); val = (char) (bytes[i] & 0x0f); temp[i * 2 + 1] = (char) (val > 9 ? val + 'A' - 10 : val + '0'); } return new String(temp); } /** * 拆分字符串 */ public static String[] splitString(String string, int len) { int x = string.length() / len; int y = string.length() % len; int z = 0; if (y != 0) { z = 1; } String[] strings = new String[x + z]; String str = ""; for (int i = 0; i < x + z; i++) { if (i == x + z - 1 && y != 0) { str = string.substring(i * len, i * len + y); } else { str = string.substring(i * len, i * len + len); } strings[i] = str; } return strings; } /** * 拆分数组 */ public static byte[][] splitArray(byte[] data, int len) { int x = data.length / len; int y = data.length % len; int z = 0; if (y != 0) { z = 1; } byte[][] arrays = new byte[x + z][]; byte[] arr; for (int i = 0; i < x + z; i++) { arr = new byte[len]; if (i == x + z - 1 && y != 0) { System.arraycopy(data, i * len, arr, 0, y); } else { System.arraycopy(data, i * len, arr, 0, len); } arrays[i] = arr; } return arrays; } public static void main(String[] args) throws Exception { // 设置长度 HashMap<String, String> keys = getKeys(); // 获取公钥 String publicKeyString = keys.get("public"); System.out.println("公钥"+publicKeyString); // 获取私钥 String privateKeyString = keys.get("private"); System.out.println("私钥"+privateKeyString); // 通过公钥加密 String hhxxttxs = encryptByPublicKey("ceshi", getPublicKey(publicKeyString)); // 获取加密后的密码 System.out.println(hhxxttxs); // 私钥解密 System.out.println(decryptByPrivateKey(hhxxttxs, getPrivateKey(privateKeyString))); } }