java.security.spec.InvalidKeySpecException: java.security.InvalidKeyException: IOException : DerInputStream.getLength(): lengthTag=111, too big.

RSA用私钥签名的时候发现报错，删除以下内容即可

 -----BEGIN PRIVATE KEY-----

-----END PRIVATE KEY-----

 

 

import org.apache.commons.codec.binary.Base64;import javax.crypto.Cipher;import java.security.*;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;/** * @author :cza * @date :2021/4/14 9:52 * @description : * @modyified By: */public class RSAEncrypt {private static Map<Integer, String> keyMap = new HashMap<Integer, String>();  //用于封装随机产生的公钥与私钥public static void main(String[] args) throws Exception {//生成公钥和私钥genKeyPair();//加密字符串String message = "df723820";System.out.println("随机生成的公钥为:" + keyMap.get(0));System.out.println("随机生成的私钥为:" + keyMap.get(1));String messageEn = encrypt(message,keyMap.get(0));System.out.println(message + "\t加密后的字符串为:" + messageEn);String messageDe = decrypt(messageEn,keyMap.get(1));System.out.println("还原后的字符串为:" + messageDe);}/** * 随机生成密钥对 * @throws NoSuchAlgorithmException */public static void genKeyPair() throws NoSuchAlgorithmException {// KeyPairGenerator类用于生成公钥和私钥对，基于RSA算法生成对象KeyPairGenerator keyPairGen = KeyPairGenerator.getInstance("RSA");// 初始化密钥对生成器，密钥大小为96-1024位keyPairGen.initialize(1024,new SecureRandom());// 生成一个密钥对，保存在keyPair中KeyPair keyPair = keyPairGen.generateKeyPair();RSAPrivateKey privateKey = (RSAPrivateKey) keyPair.getPrivate();// 得到私钥RSAPublicKey publicKey = (RSAPublicKey) keyPair.getPublic();  // 得到公钥String publicKeyString = new String(Base64.encodeBase64(publicKey.getEncoded()));// 得到私钥字符串String privateKeyString = new String(Base64.encodeBase64((privateKey.getEncoded())));// 将公钥和私钥保存到MapkeyMap.put(0,publicKeyString);  //0表示公钥keyMap.put(1,privateKeyString);  //1表示私钥}/** * RSA公钥加密 * * @param str *加密字符串 * @param publicKey *公钥 * @retu 密文 * @throws Exception * 加密过程中的异常信息 */public static String encrypt(String str, String publicKey ) throws Exception {//base64编码的公钥byte[] decoded = Base64.decodeBase64(publicKey);RSAPublicKey pubKey = (RSAPublicKey) KeyFactory.getInstance("RSA").generatePublic(new X509EncodedKeySpec(decoded));//RSA加密Cipher cipher = Cipher.getInstance("RSA");cipher.init(Cipher.ENCRYPT_MODE, pubKey);String outStr = Base64.encodeBase64String(cipher.doFinal(str.getBytes("UTF-8")));retu outStr;}/** * RSA私钥解密 * * @param str *加密字符串 * @param privateKey *私钥 * @retu 铭文 * @throws Exception * 解密过程中的异常信息 */public static String decrypt(String str, String privateKey) throws Exception {//64位解码加密后的字符串byte[] inputByte = Base64.decodeBase64(str.getBytes("UTF-8"));//base64编码的私钥byte[] decoded = Base64.decodeBase64(privateKey);RSAPrivateKey priKey = (RSAPrivateKey) KeyFactory.getInstance("RSA").generatePrivate(new PKCS8EncodedKeySpec(decoded));//RSA解密Cipher cipher = Cipher.getInstance("RSA");cipher.init(Cipher.DECRYPT_MODE, priKey);String outStr = new String(cipher.doFinal(inputByte));retu outStr;}/** * 签名 * * @param data 待签名数据 * @param privateKey 私钥 * @retu 签名 */public static String sign(String data, PrivateKey privateKey) throws Exception {byte[] keyBytes = privateKey.getEncoded();PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(keyBytes);KeyFactory keyFactory = KeyFactory.getInstance("RSA");PrivateKey key = keyFactory.generatePrivate(keySpec);Signature signature = Signature.getInstance("MD5withRSA");signature.initSign(key);signature.update(data.getBytes());retu new String(Base64.encodeBase64(signature.sign()));}/** * rsa签名 * * @param content *待签名的字符串 * @param privateKey *rsa私钥字符串 * @param charset *字符编码 * @retu 签名结果 * @throws Exception * 签名失败则抛出异常 */public static String sign(String content, String privateKey) throws Exception {//base64编码的私钥byte[] decoded = Base64.decodeBase64(privateKey);try {//RSAPrivateKey priKey = (RSAPrivateKey) KeyFactory.getInstance("RSA").generatePrivate(new PKCS8EncodedKeySpec(decoded));// 取得私钥byte[] pri_key_bytes = Base64.decodeBase64(privateKey);PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(pri_key_bytes);KeyFactory keyFactory = KeyFactory.getInstance("RSA");// 生成私钥PrivateKey priKey = keyFactory.generatePrivate(pkcs8KeySpec);retu sign(content,priKey);} catch (Exception e) {e.printStackTrace();throw e;}}/** * 验签 * * @param srcData 原始字符串 * @param publicKey 公钥 * @param sign 签名 * @retu 是否验签通过 */public static boolean verify(String srcData, PublicKey publicKey, String sign) throws Exception {byte[] keyBytes = publicKey.getEncoded();X509EncodedKeySpec keySpec = new X509EncodedKeySpec(keyBytes);KeyFactory keyFactory = KeyFactory.getInstance("RSA");PublicKey key = keyFactory.generatePublic(keySpec);Signature signature = Signature.getInstance("MD5withRSA");signature.initVerify(key);signature.update(srcData.getBytes());retu signature.verify(Base64.decodeBase64(sign.getBytes()));}/** * 验签 * * @param srcData 原始字符串 * @param publicKey 公钥 * @param sign 签名 * @retu 是否验签通过 */public static boolean verify(String srcData, String publicKey, String sign) throws Exception {byte[] publicBytes = Base64.decodeBase64(publicKey);X509EncodedKeySpec keySpec = new X509EncodedKeySpec(publicBytes);KeyFactory keyFactory = KeyFactory.getInstance("RSA");PublicKey pubKey = keyFactory.generatePublic(keySpec);retu verify(srcData,pubKey,sign);}