Android-rsa解密服务端给的加密过的内容,利用rsa公钥解密方式解密,先decode再解密

内容后台加密方式:Base64 encode加密 -> Rsa私钥加密, 给我公钥用来解密, 实现方式参考:PHP实现RSA加解密

前端界面方式:Base64 *decode解密->Rsa公钥解密, 参考 *Android数据加密之Rsa加密 - 总李写代码 - 博客园 CSDN-专业IT技术社区-登录 Android加密算法-我参考这个修改完善了了之前其他资料的公钥分块解密。。

最后从调用方式提供工具类:- 如果你的遇到一些问题,比较后台加密方式不同,你需要查阅资料修改一些获取公钥的一些参数,有时候也会有错误提示。我没具体研究加密,就没有怎么深入。。。。喵...

RsaDataUtil.java - 注意这个方法CryptorNatvie.getPubliscKey(MyApplication.getInstance())/GlobalAppInfo.public_key/)是我获取本地so里面的一个rsa公钥的方式。你可以直接替换为自己的公钥字符串。

    /**
*@Author: hl
*@Date: created at 2019/12/25 11:43
*@Description: 获取RAS加密内容工具
*/
public class RsaDataUtil {

    /**
     * 解密RAS字符串
     * @param originStr
     * @return
     */
    public static String getContentByRSA(String originStr) {
        try {
            byte[] bytes = RSAUtil.decryptWithPublicKeyBlock(
                    Base64Util.decodeToBytes(originStr),
                    CryptorNatvie.getPubliscKey(MyApplication.getInstance())/*GlobalAppInfo.public_key*/);
            return new String(bytes, "UTF-8");
        } catch (Exception e) {
            e.printStackTrace();
        }
        return "";
    }
}

RSAUtil.java - 具体的Rsa加密解密方式,我这里重点关注decryptWithPublicKeyBlock

import java.io.BufferedReader;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.math.BigInteger;
import java.security.Key;
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.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.InvalidKeySpecException;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.RSAPublicKeySpec;
import java.security.spec.X509EncodedKeySpec;

import javax.crypto.Cipher;

/**
 * @Author: hl
 * @Date: created at 2019/12/25 11:02
 * @Description: RSA加密解密工具
 */
public class RSAUtil {
    /**
     * 某些时候,后台(目前php后台)给的公钥并不支持RSA/ECB/PKCS1Padding算法,所以我们只需要RSA算法来通过公钥获取解密的key
     * 因此:分开两个变量使用
     */
    private static String ECB_PADDING = "RSA/ECB/PKCS1Padding";
    private static String RSA = "RSA";

    /**
     * RSA算法规定:待加密的字节数不能超过密钥的长度值除以8再减去11。
     * 而加密后得到密文的字节数,正好是密钥的长度值除以 8。
     */
    private static int KEYSIZE = 2048;// 密钥位数
    private static int RESERVE_BYTES = 11;
    private static int DECRYPT_BLOCK = KEYSIZE / 8;
    private static int ENCRYPT_BLOCK = DECRYPT_BLOCK - RESERVE_BYTES;

    /**
     * 随机生成RSA密钥对范围:512~2048
     * (默认密钥长度为1024)
     */
    public static KeyPair generateRSAKeyPair() {
        return generateRSAKeyPair(1024);
    }

    /**
     * 随机生成RSA密钥对
     */
    public static KeyPair generateRSAKeyPair(int keyLength) {
        try {
            KeyPairGenerator kpg = KeyPairGenerator.getInstance(RSA);
            kpg.initialize(keyLength);
            return kpg.genKeyPair();
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
            return null;
        }
    }

    /**
     * 用公钥加密
     */
    public static byte[] encryptDataPublic(byte[] data, PublicKey publicKey) {

        try {
            // 对数据加密
            Cipher cipher = Cipher.getInstance(RSA);
            // 编码前设定编码方式及密钥
            cipher.init(Cipher.ENCRYPT_MODE, publicKey);
            // 传入编码数据并返回编码结果
            return cipher.doFinal(data);
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }

    /**
     * 用公钥解密 - 传PublicKey的方式
     */
    public static byte[] decryptDataPublic(byte[] data, PublicKey publicKey) {

        try {
            // 对数据解密
            Cipher cipher = Cipher.getInstance(RSA);
            cipher.init(Cipher.DECRYPT_MODE, publicKey);
            return cipher.doFinal(data);
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }

    /**
     * 分块公钥加密
     *
     * @param data
     * @param key
     */
    public static byte[] encryptWithPublicKeyBlock(byte[] data, byte[] key) throws Exception {
        int blockCount = (data.length / ENCRYPT_BLOCK);

        if ((data.length % ENCRYPT_BLOCK) != 0) {
            blockCount += 1;
        }

        ByteArrayOutputStream bos = new ByteArrayOutputStream(blockCount * ENCRYPT_BLOCK);
        Cipher cipher = Cipher.getInstance(ECB_PADDING);
        cipher.init(Cipher.ENCRYPT_MODE, getPublicKey(key));

        for (int offset = 0; offset < data.length; offset += ENCRYPT_BLOCK) {
            int inputLen = (data.length - offset);
            if (inputLen > ENCRYPT_BLOCK) {
                inputLen = ENCRYPT_BLOCK;
            }
            byte[] encryptedBlock = cipher.doFinal(data, offset, inputLen);
            bos.write(encryptedBlock);
        }

        bos.close();
        return bos.toByteArray();
    }

    /**
     * 用公钥解密 - 传字符串的方式
     * ECB_PADDING--当前我的php后台数据加密方式
     */
    public static byte[] decryptDataPublic(byte[] data, String _publicKey) {

        try {
            PublicKey publicKey = loadPublicKey(_publicKey);
            // 对数据解密
            Cipher cipher = Cipher.getInstance(ECB_PADDING);
            cipher.init(Cipher.DECRYPT_MODE, publicKey);
            byte[] resultBytes = cipher.doFinal(data);
            return resultBytes;
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

    /**
     * 分块公钥解密
     *
     * @param data
     * @param key
     */
    public static byte[] decryptWithPublicKeyBlock(byte[] data, byte[] key) throws Exception {
        int blockCount = (data.length / DECRYPT_BLOCK);
        if ((data.length % DECRYPT_BLOCK) != 0) {
            blockCount += 1;
        }
        ByteArrayOutputStream bos = new ByteArrayOutputStream(blockCount * DECRYPT_BLOCK);
        Cipher cipher = Cipher.getInstance(ECB_PADDING);
        cipher.init(Cipher.DECRYPT_MODE, getPublicKey(key));
        for (int offset = 0; offset < data.length; offset += DECRYPT_BLOCK) {
            int inputLen = (data.length - offset);
            if (inputLen > DECRYPT_BLOCK) {
                inputLen = DECRYPT_BLOCK;
            }
            byte[] decryptedBlock = cipher.doFinal(data, offset, inputLen);
            bos.write(decryptedBlock);
        }

        bos.close();
        return bos.toByteArray();
    }

    /**
     * 分块公钥解密
     *
     * @param data
     * @param _publicKey
     */
    public static byte[] decryptWithPublicKeyBlock(byte[] data, String _publicKey) throws Exception {
        int blockCount = (data.length / DECRYPT_BLOCK);
        if ((data.length % DECRYPT_BLOCK) != 0) {
            blockCount += 1;
        }
        ByteArrayOutputStream bos = new ByteArrayOutputStream(blockCount * DECRYPT_BLOCK);
        Cipher cipher = Cipher.getInstance(ECB_PADDING);
        cipher.init(Cipher.DECRYPT_MODE, loadPublicKey(_publicKey));
        for (int offset = 0; offset < data.length; offset += DECRYPT_BLOCK) {
            int inputLen = (data.length - offset);
            if (inputLen > DECRYPT_BLOCK) {
                inputLen = DECRYPT_BLOCK;
            }
            byte[] decryptedBlock = cipher.doFinal(data, offset, inputLen);
            bos.write(decryptedBlock);
        }

        bos.close();
        return bos.toByteArray();
    }

    /**
     * 用私钥加密
     */
    public static byte[] encryptDataPrivate(byte[] data, PrivateKey privateKey) {
        try {
            // 对数据加密
            Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
            cipher.init(Cipher.ENCRYPT_MODE, privateKey);

            return cipher.doFinal(data);
        } catch (Exception e) {
            return null;
        }
    }

    /**
     * 分块私钥加密
     *
     * @param data
     * @param key
     */
    public static byte[] encryptWithPrivateKeyBlock(byte[] data, byte[] key) throws Exception {
        int blockCount = (data.length / ENCRYPT_BLOCK);

        if ((data.length % ENCRYPT_BLOCK) != 0) {
            blockCount += 1;
        }
        ByteArrayOutputStream bos = new ByteArrayOutputStream(blockCount * ENCRYPT_BLOCK);
        Cipher cipher = Cipher.getInstance(ECB_PADDING);
        cipher.init(Cipher.ENCRYPT_MODE, getPrivateKey(key));

        for (int offset = 0; offset < data.length; offset += ENCRYPT_BLOCK) {
            int inputLen = (data.length - offset);
            if (inputLen > ENCRYPT_BLOCK) {
                inputLen = ENCRYPT_BLOCK;
            }
            byte[] encryptedBlock = cipher.doFinal(data, offset, inputLen);
            bos.write(encryptedBlock);
        }

        bos.close();
        return bos.toByteArray();
    }

    /**
     * 用私钥解密
     */
    public static byte[] decryptDataPrivate(byte[] data, PrivateKey privateKey) {
        try {
            // 对数据解密
            Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
            cipher.init(Cipher.DECRYPT_MODE, privateKey);
            return cipher.doFinal(data);
        } catch (Exception e) {
            return null;
        }
    }

    /**
     * 分块私钥解密
     *
     * @param data
     * @param key
     */
    public static byte[] decryptWithPrivateKeyBlock(byte[] data, byte[] key) throws Exception {
        int blockCount = (data.length / DECRYPT_BLOCK);
        if ((data.length % DECRYPT_BLOCK) != 0) {
            blockCount += 1;
        }
        ByteArrayOutputStream bos = new ByteArrayOutputStream(blockCount * DECRYPT_BLOCK);
        Cipher cipher = Cipher.getInstance(ECB_PADDING);
        cipher.init(Cipher.DECRYPT_MODE, getPrivateKey(key));
        for (int offset = 0; offset < data.length; offset += DECRYPT_BLOCK) {
            int inputLen = (data.length - offset);

            if (inputLen > DECRYPT_BLOCK) {
                inputLen = DECRYPT_BLOCK;
            }

            byte[] decryptedBlock = cipher.doFinal(data, offset, inputLen);
            bos.write(decryptedBlock);
        }

        bos.close();
        return bos.toByteArray();
    }

    /**
     * 通过公钥byte[](publicKey.getEncoded())将公钥还原,适用于RSA算法
     *
     * @param keyBytes
     * @return
     * @throws NoSuchAlgorithmException
     * @throws InvalidKeySpecException
     */
    public static PublicKey getPublicKey(byte[] keyBytes) throws NoSuchAlgorithmException,
            InvalidKeySpecException {
        X509EncodedKeySpec keySpec = new X509EncodedKeySpec(keyBytes);
        KeyFactory keyFactory = KeyFactory.getInstance(RSA);
        PublicKey publicKey = keyFactory.generatePublic(keySpec);
        return publicKey;
    }

    /**
     * 通过私钥byte[]将公钥还原,适用于RSA算法
     *
     * @param keyBytes
     * @return
     * @throws NoSuchAlgorithmException
     * @throws InvalidKeySpecException
     */
    public static PrivateKey getPrivateKey(byte[] keyBytes) throws NoSuchAlgorithmException,
            InvalidKeySpecException {
        PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(keyBytes);
        KeyFactory keyFactory = KeyFactory.getInstance(RSA);
        PrivateKey privateKey = keyFactory.generatePrivate(keySpec);
        return privateKey;
    }

    /**
     * 使用N、e值还原公钥
     *
     * @param modulus
     * @param publicExponent
     * @return
     * @throws NoSuchAlgorithmException
     * @throws InvalidKeySpecException
     */
    public static PublicKey getPublicKey(String modulus, String publicExponent)
            throws NoSuchAlgorithmException, InvalidKeySpecException {
        BigInteger bigIntModulus = new BigInteger(modulus);
        BigInteger bigIntPrivateExponent = new BigInteger(publicExponent);
        RSAPublicKeySpec keySpec = new RSAPublicKeySpec(bigIntModulus, bigIntPrivateExponent);
        KeyFactory keyFactory = KeyFactory.getInstance(RSA);
        PublicKey publicKey = keyFactory.generatePublic(keySpec);
        return publicKey;
    }

    /**
     * 使用N、d值还原私钥
     *
     * @param modulus
     * @param privateExponent
     * @return
     * @throws NoSuchAlgorithmException
     * @throws InvalidKeySpecException
     */
    public static PrivateKey getPrivateKey(String modulus, String privateExponent)
            throws NoSuchAlgorithmException, InvalidKeySpecException {
        BigInteger bigIntModulus = new BigInteger(modulus);
        BigInteger bigIntPrivateExponent = new BigInteger(privateExponent);
        RSAPublicKeySpec keySpec = new RSAPublicKeySpec(bigIntModulus, bigIntPrivateExponent);
        KeyFactory keyFactory = KeyFactory.getInstance(RSA);
        PrivateKey privateKey = keyFactory.generatePrivate(keySpec);
        return privateKey;
    }

    /**
     * 从字符串中加载公钥
     *
     * @param publicKeyStr 公钥数据字符串
     * @throws Exception 加载公钥时产生的异常
     *                   RSA - 当前我的后台给的公钥的生成算法是RSA
     */
    public static PublicKey loadPublicKey(String publicKeyStr) throws Exception {
        try {
            byte[] buffer = Base64Util.decode(publicKeyStr);
            KeyFactory keyFactory = KeyFactory.getInstance(RSA);
            X509EncodedKeySpec keySpec = new X509EncodedKeySpec(buffer);
            return keyFactory.generatePublic(keySpec);
        } catch (NoSuchAlgorithmException e) {
            throw new Exception("无此算法");
        } catch (InvalidKeySpecException e) {
            throw new Exception("公钥非法");
        } catch (NullPointerException e) {
            throw new Exception("公钥数据为空");
        }
    }

    /**
     * 从字符串中加载私钥
* 加载时使用的是PKCS8EncodedKeySpec(PKCS#8编码的Key指令)。 * * @param privateKeyStr * @return * @throws Exception */ public static PrivateKey loadPrivateKey(String privateKeyStr) throws Exception { try { byte[] buffer = Base64Util.decode(privateKeyStr); PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(buffer); KeyFactory keyFactory = KeyFactory.getInstance(RSA); return keyFactory.generatePrivate(keySpec); } catch (NoSuchAlgorithmException e) { throw new Exception("无此算法"); } catch (InvalidKeySpecException e) { throw new Exception("私钥非法"); } catch (NullPointerException e) { throw new Exception("私钥数据为空"); } } /** * 从文件中输入流中加载公钥 * * @param in 公钥输入流 * @throws Exception 加载公钥时产生的异常 */ public static PublicKey loadPublicKey(InputStream in) throws Exception { try { return loadPublicKey(readKey(in)); } catch (IOException e) { throw new Exception("公钥数据流读取错误"); } catch (NullPointerException e) { throw new Exception("公钥输入流为空"); } } /** * 从文件中加载私钥 * * @param in 私钥文件名 * @return 是否成功 * @throws Exception */ public static PrivateKey loadPrivateKey(InputStream in) throws Exception { try { return loadPrivateKey(readKey(in)); } catch (IOException e) { throw new Exception("私钥数据读取错误"); } catch (NullPointerException e) { throw new Exception("私钥输入流为空"); } } /** * 读取密钥信息 * * @param in * @return * @throws IOException */ private static String readKey(InputStream in) throws IOException { BufferedReader br = new BufferedReader(new InputStreamReader(in)); String readLine = null; StringBuilder sb = new StringBuilder(); while ((readLine = br.readLine()) != null) { if (readLine.charAt(0) == '-') { continue; } else { sb.append(readLine); sb.append('\r'); } } return sb.toString(); } /** * 打印公钥信息 * * @param publicKey */ public static void printPublicKeyInfo(PublicKey publicKey) { RSAPublicKey rsaPublicKey = (RSAPublicKey) publicKey; System.out.println("----------RSAPublicKey----------"); System.out.println("Modulus.length=" + rsaPublicKey.getModulus().bitLength()); System.out.println("Modulus=" + rsaPublicKey.getModulus().toString()); System.out.println("PublicExponent.length=" + rsaPublicKey.getPublicExponent().bitLength()); System.out.println("PublicExponent=" + rsaPublicKey.getPublicExponent().toString()); } /** * 打印公钥信息 * * @param privateKey */ public static void printPrivateKeyInfo(PrivateKey privateKey) { RSAPrivateKey rsaPrivateKey = (RSAPrivateKey) privateKey; System.out.println("----------RSAPrivateKey ----------"); System.out.println("Modulus.length=" + rsaPrivateKey.getModulus().bitLength()); System.out.println("Modulus=" + rsaPrivateKey.getModulus().toString()); System.out.println("PrivateExponent.length=" + rsaPrivateKey.getPrivateExponent().bitLength()); System.out.println("PrivatecExponent=" + rsaPrivateKey.getPrivateExponent().toString()); } /** * 得到密钥字符串(经过base64编码) */ public static String getKeyString(Key key) throws Exception { byte[] keyBytes = key.getEncoded(); String s = Base64Util.encode(keyBytes); return s; } /** * 16进制字符串转字节数组 * * @param src 16进制字符串 * @return 字节数组 * @throws */ public static byte[] hexString2Bytes(String src) { int l = src.length() / 2; byte[] ret = new byte[l]; for (int i = 0; i < l; i++) { ret[i] = (byte) Integer .valueOf(src.substring(i * 2, i * 2 + 2), 16).byteValue(); } return ret; } /** * 16进制字符串转字符串 * * @param src 16进制字符串 * @return 字节数组 * @throws */ public static String hexString2String(String src) { String temp = ""; for (int i = 0; i < src.length() / 2; i++) { temp = temp + (char) Integer.valueOf(src.substring(i * 2, i * 2 + 2), 16).byteValue(); } return temp; } /** * 字符串转16进制字符串 * * @param strPart 字符串 * @return 16进制字符串 * @throws */ public static String string2HexString(String strPart) { StringBuffer hexString = new StringBuffer(); for (int i = 0; i < strPart.length(); i++) { int ch = (int) strPart.charAt(i); String strHex = Integer.toHexString(ch); hexString.append(strHex); } return hexString.toString(); } /** * 字节数组转16进制字符串 * * @param b 字节数组 * @return 16进制字符串 * @throws */ public static String bytes2HexString(byte[] b) { StringBuffer result = new StringBuffer(); String hex; for (int i = 0; i < b.length; i++) { hex = Integer.toHexString(b[i] & 0xFF); if (hex.length() == 1) { hex = '0' + hex; } result.append(hex.toUpperCase()); } return result.toString(); } }

Base64Util.java - Base64解压处理,采用了android本身提供的方式

import android.util.Base64;

import java.io.UnsupportedEncodingException;

public class Base64Util {

    /******************************************非官方**************************************/
    private static char[] base64EncodeChars = new char[]
            {'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T',
                    'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm',
                    'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', '0', '1', '2', '3', '4', '5',
                    '6', '7', '8', '9', '+', '/'};

    private static byte[] base64DecodeChars = new byte[]
            {-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
                    -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, -1, -1, 63, 52, 53,
                    54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11,
                    12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1, -1, 26, 27, 28, 29,
                    30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1,
                    -1, -1, -1};

    /**
     * 加密
     *
     * @param data
     * @return
     */
    public static String encode(byte[] data) {
        return decodePublic(data);
    }

    /**
     * 解密
     *
     * @param str
     * @return
     */
    public static byte[] decode(String str) {
        try {
            return decodePrivate(str);
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        return new byte[]{};
    }

    private static byte[] decodePrivate(String str) throws UnsupportedEncodingException {
        StringBuffer sb = new StringBuffer();
        byte[] data = str.getBytes("US-ASCII");
        int len = data.length;
        int i = 0;
        int b1, b2, b3, b4;

        while (i < len) {
            do {
                b1 = base64DecodeChars[data[i++]];
            } while (i < len && b1 == -1);
            if (b1 == -1)
                break;

            do {
                b2 = base64DecodeChars[data[i++]];
            } while (i < len && b2 == -1);
            if (b2 == -1)
                break;
            sb.append((char) ((b1 << 2) | ((b2 & 0x30) >>> 4)));

            do {
                b3 = data[i++];
                if (b3 == 61)
                    return sb.toString().getBytes("iso8859-1");
                b3 = base64DecodeChars[b3];
            } while (i < len && b3 == -1);
            if (b3 == -1)
                break;
            sb.append((char) (((b2 & 0x0f) << 4) | ((b3 & 0x3c) >>> 2)));

            do {
                b4 = data[i++];
                if (b4 == 61)
                    return sb.toString().getBytes("iso8859-1");
                b4 = base64DecodeChars[b4];
            } while (i < len && b4 == -1);
            if (b4 == -1)
                break;
            sb.append((char) (((b3 & 0x03) << 6) | b4));
        }

        return sb.toString().getBytes("iso8859-1");
    }

    private static String decodePublic(byte[] data) {

        StringBuffer sb = new StringBuffer();
        int len = data.length;
        int i = 0;
        int b1, b2, b3;
        while (i < len) {
            b1 = data[i++] & 0xff;
            if (i == len) {
                sb.append(base64EncodeChars[b1 >>> 2]);
                sb.append(base64EncodeChars[(b1 & 0x3) << 4]);
                sb.append("==");
                break;
            }
            b2 = data[i++] & 0xff;
            if (i == len) {
                sb.append(base64EncodeChars[b1 >>> 2]);
                sb.append(base64EncodeChars[((b1 & 0x03) << 4) | ((b2 & 0xf0) >>> 4)]);
                sb.append(base64EncodeChars[(b2 & 0x0f) << 2]);
                sb.append("=");
                break;
            }
            b3 = data[i++] & 0xff;
            sb.append(base64EncodeChars[b1 >>> 2]);
            sb.append(base64EncodeChars[((b1 & 0x03) << 4) | ((b2 & 0xf0) >>> 4)]);
            sb.append(base64EncodeChars[((b2 & 0x0f) << 2) | ((b3 & 0xc0) >>> 6)]);
            sb.append(base64EncodeChars[b3 & 0x3f]);
        }
        return sb.toString();
    }

    /******************************************官方**************************************/
    /**
     * 【官】解密
     * @param str - 纯字母,就不搞utf-8编码了
     * @return
     */
    public static byte[] decodeToBytes(String str){
        //        try {
        //            return Base64.decode(str.getBytes("utf-8"), Base64.DEFAULT);
        //        } catch (UnsupportedEncodingException e) {
        //            e.printStackTrace();
        //        }
        //        return null;
        return Base64.decode(str.getBytes(), Base64.DEFAULT);
    }
}

基本没啥问题了

[图片上传中...(image-d836fe-1579151205237-4)]

问题:

1. 如果不分块解密可能会报错: - 一下不能进行太多字节解密

  javax.crypto.IllegalBlockSizeException: input must be under 256 bytes

2. 具体忘了,应该也是rsa获取公钥出的问题...

java.lang.ArrayIndexOutOfBoundsException: too much data for RSA block

3. 获取公钥方式key出问题,可能出现 ,具体是loadPublicKey(String publickey)方法,里面涉及到SSLX509Certificate等问题,这具体看后台加密的方式

 java.security.spec.InvalidKeySpecException: com.android.org.conscrypt.OpenSSLX509CertificateFactory$ParsingException: Error parsing public key

java.security.spec.InvalidKeySpecException: encoded key spec not recognized: failed to construct sequence from byte[]: unknown tag 13 encountered

4. 记得公钥去掉-----BEGIN PUBLIC KEY----- -----END PUBLIC KEY-----

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我的格式如下(\n没去掉试哈哈,保留了,你可以去掉试试。。嘻嘻) - 我定义在cpp文件了,打包成了so,让破解更难些。。。另外加了**签名校验 参考 **CSDN-专业IT技术社区-登录,防止so直接被调用...

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cryptor.cpp - 直接给出来吧。需要可以参考

#include 
#include 

const char *app_signature_sha1="E561477307CDxxxxxxxx815EC4A014DF";
const char HexCode[]={'0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F'};

extern "C" JNIEXPORT jstring JNICALL
Java_com_lieyun_rsa_CryptorNatvie_getPubliscKey(
        JNIEnv* env,
        jclass type,
        jobject context_object) {
    jclass context_class = env->GetObjectClass(context_object);

    //context.getPackageManager()
    jmethodID methodId = env->GetMethodID(context_class, "getPackageManager", "()Landroid/content/pm/PackageManager;");
    jobject package_manager_object = env->CallObjectMethod(context_object, methodId);
    if (package_manager_object == NULL) {
        std::string rsa_keysbhello = "hello";
        return env->NewStringUTF(rsa_keysbhello.c_str());
    }

    //context.getPackageName()
    methodId = env->GetMethodID(context_class, "getPackageName", "()Ljava/lang/String;");
    jstring package_name_string = (jstring)env->CallObjectMethod(context_object, methodId);
    if (package_name_string == NULL) {
        std::string rsa_keysbheys = "heys";
        return env->NewStringUTF(rsa_keysbheys.c_str());
    }
    env->DeleteLocalRef(context_class);

    //PackageManager.getPackageInfo(Sting, int)
    //public static final int GET_SIGNATURES= 0x00000040;
    jclass pack_manager_class = env->GetObjectClass(package_manager_object);
    methodId = env->GetMethodID(pack_manager_class, "getPackageInfo", "(Ljava/lang/String;I)Landroid/content/pm/PackageInfo;");
    env->DeleteLocalRef(pack_manager_class);
    jobject package_info_object = env->CallObjectMethod(package_manager_object, methodId, package_name_string, 0x40);
    if (package_info_object == NULL) {
        std::string rsa_keysbhey = "hey";
        return env->NewStringUTF(rsa_keysbhey.c_str());
    }
    env->DeleteLocalRef(package_manager_object);

    //PackageInfo.signatures[0]
    jclass package_info_class = env->GetObjectClass(package_info_object);
    jfieldID fieldId = env->GetFieldID(package_info_class, "signatures", "[Landroid/content/pm/Signature;");
    env->DeleteLocalRef(package_info_class);
    jobjectArray signature_object_array = (jobjectArray)env->GetObjectField(package_info_object, fieldId);
    if (signature_object_array == NULL) {
        std::string rsa_keysbfuck = "fuck";
        return env->NewStringUTF(rsa_keysbfuck.c_str());
    }
    jobject signature_object = env->GetObjectArrayElement(signature_object_array, 0);
    env->DeleteLocalRef(package_info_object);

    //Signature.toByteArray()
    jclass signature_class = env->GetObjectClass(signature_object);
    methodId = env->GetMethodID(signature_class, "toByteArray", "()[B");
    env->DeleteLocalRef(signature_class);
    jbyteArray signature_byte = (jbyteArray) env->CallObjectMethod(signature_object, methodId);

    //new ByteArrayInputStream - 这里报错了,但是不影响打包和运行
    jclass byte_array_input_class=env->FindClass("java/io/ByteArrayInputStream");
    methodId=env->GetMethodID(byte_array_input_class,"","([B)V");
    jobject byte_array_input=env->NewObject(byte_array_input_class,methodId,signature_byte);

    //CertificateFactory.getInstance("X.509")
    jclass certificate_factory_class=env->FindClass("java/security/cert/CertificateFactory");
    methodId=env->GetStaticMethodID(certificate_factory_class,"getInstance","(Ljava/lang/String;)Ljava/security/cert/CertificateFactory;");
    jstring x_509_jstring=env->NewStringUTF("X.509");
    jobject cert_factory=env->CallStaticObjectMethod(certificate_factory_class,methodId,x_509_jstring);

    //certFactory.generateCertificate(byteIn);
    methodId=env->GetMethodID(certificate_factory_class,"generateCertificate",("(Ljava/io/InputStream;)Ljava/security/cert/Certificate;"));
    jobject x509_cert=env->CallObjectMethod(cert_factory,methodId,byte_array_input);
    env->DeleteLocalRef(certificate_factory_class);

    //cert.getEncoded()
    jclass x509_cert_class=env->GetObjectClass(x509_cert);
    methodId=env->GetMethodID(x509_cert_class,"getEncoded","()[B");
    jbyteArray cert_byte=(jbyteArray)env->CallObjectMethod(x509_cert,methodId);
    env->DeleteLocalRef(x509_cert_class);

    //MessageDigest.getInstance("SHA1")
    jclass message_digest_class=env->FindClass("java/security/MessageDigest");
    methodId=env->GetStaticMethodID(message_digest_class,"getInstance","(Ljava/lang/String;)Ljava/security/MessageDigest;");
    jstring sha1_jstring=env->NewStringUTF("SHA1");
    jobject sha1_digest=env->CallStaticObjectMethod(message_digest_class,methodId,sha1_jstring);

    //sha1.digest (certByte)
    methodId=env->GetMethodID(message_digest_class,"digest","([B)[B");
    jbyteArray sha1_byte=(jbyteArray)env->CallObjectMethod(sha1_digest,methodId,cert_byte);
    env->DeleteLocalRef(message_digest_class);

    //toHexString
    jsize array_size=env->GetArrayLength(sha1_byte);
    jbyte* sha1 =env->GetByteArrayElements(sha1_byte,NULL);
    char *hex_sha=new char[array_size*2+1];
    for (int i = 0; i NewStringUTF(rsa_key.c_str());
    } else{
        std::string rsa_keysb = "sb";
        return env->NewStringUTF(rsa_keysb.c_str());
    }
}

//jobject getApplication(JNIEnv *env) {
//    jclass localClass = (*env)->FindClass(env,"android/app/ActivityThread");
//    if (localClass!=NULL)
//    {
//        // LOGI("class have find");
//        jmethodID getapplication = (*env)->GetStaticMethodID(env,localClass, "currentApplication", "()Landroid/app/Application;");
//        if (getapplication!=NULL)
//        {
//            jobject application = (*env)->CallStaticObjectMethod(env,localClass, getapplication);
//            return application;
//        }
//        return NULL;
//    }
//    return NULL;
//}

//void exitApplication(JNIEnv *env, jint flag){
//    jclass temp_clazz = NULL;
//    jmethodID mid_static_method;
//    // 1、从classpath路径下搜索ClassMethod这个类,并返回该类的Class对象
//    temp_clazz =(*env)->FindClass(env,"java/lang/System");
//    mid_static_method = (*env)->GetStaticMethodID(env,temp_clazz,"exit","(I)V");
//    (*env)->CallStaticVoidMethod(env,temp_clazz,mid_static_method,flag);
//    (*env)->DeleteLocalRef(env,temp_clazz);
//}

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上面这是签名文件的sha1值,替换自己的

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上面这是rsa公钥字符串(处理了begin和end。。\n保留了。如果有问题可以再多调试)

到此基本就搞定了rsa界面,然后做了基本的so加密处理。。。顺便复习了下native编程。。哇咔咔。。。加油。。

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