android 和 Koa2 服务器 在 RSA加密上的 通用算法

首先在koa2上

var RSAJS = null
var RSAPKEY = null//需传递给客户端使用的公钥,在android端调用 getPKey()方法 生成 android使用的publickey
var RSASKEY = null 
function RSAInit() {
    var NodeRSA = require("node-rsa");
    RSAJS = new NodeRSA({b:1024})
    RSAJS.setOptions({encryptionScheme: 'pkcs1'});
    RSAPKEY = RSAJS.exportKey('public');
    RSASKEY = RSAJS.exportKey('private');
    let newpks = RSAPKEY.split("\n")
    let kp = ""
    for (let i = 1; i < newpks.length - 1; i++) {
        const element = newpks[i];
        if(i == newpks.length - 2){
            kp+=element;
        }else{
            kp+=element+"\n";
        }
    }
    RSASKEY = kp
}
function RSAEncrypt(value) {
    return RSAJS.encryptPrivate(value, 'base64')
}

function RSADecrypt(value) {
    return RSAJS.decryptPublic(value, 'utf8')
}
RSAInit()

在android上使用的

 

//注意在android上使用koa2的pkey的时候需要吧 -----BEGIN PUBLIC KEY----- 和 -----END PUBLIC KEY----- 去掉 

//类似此种

//PublicKey pk = //RSAUtil.getPKey("MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCHZ3cCV863r2aDaAg5wUS39vrF\n" +
//              "1yoCbQQhuUMbtDc3VJImLpZk54aVN8jR1cG7JdyozboZbBeDNhlEhNBfjH8wwiED\n" +
//              "LOmNfLZCDGbFfiVyfNdwnUa+uAbuMsy6p0vNeizPxt7XhDG4AJK2Mvfea1d2oKhR\n" +
//              "oTvgHQIqQcPdATRZ0QIDAQAB");
    public static PublicKey getPKey(String pkey) throws Exception {
        byte[] keyBytes = Base64.decode(pkey,Base64.DEFAULT);
        X509EncodedKeySpec spec = new X509EncodedKeySpec(keyBytes);
        PublicKey publicKey = null;

        try {
            KeyFactory kf = KeyFactory.getInstance("RSA");
            publicKey = kf.generatePublic(spec);

        } catch (Exception e) {
            e.printStackTrace();
        }

        return publicKey;
    }    
    public static byte[] encryptByPublicKey(PublicKey pubKey, byte[] data) throws Exception {
        return doFinal(pubKey, Mode.ENCRYPT, data);
    }

    public static byte[] decryptByPrivateKey(PrivateKey priKey, byte[] data) throws Exception {
        return doFinal(priKey, Mode.DECRYPT, Base64.decode(data,Base64.DEFAULT));
    }

    public static byte[] encryptByPrivateKey(PrivateKey priKey, byte[] data) throws Exception {
        return doFinal(priKey, Mode.ENCRYPT, data);
    }

    public static byte[] decryptByPublicKey(PublicKey pubKey, byte[] data) throws Exception {
        return doFinal(pubKey, Mode.DECRYPT, Base64.decode(data,Base64.DEFAULT));
    }

    private static byte[] doFinal(Key key, Mode mode, byte[] data) throws Exception {
        final int MAX = (mode == Mode.ENCRYPT) ? MAX_ENCRYPT_BLOCK : MAX_DECRYPT_BLOCK;
        final int LEN = data.length;
        byte[] cache;
        int i = 0, off = 0;

        ByteArrayOutputStream out = new ByteArrayOutputStream();
        Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1PADDING");
        cipher.init(mode.value, key);
        while (off < LEN) {
            cache = cipher.doFinal(data, off, Math.min(LEN - off, MAX));
            out.write(cache, 0, cache.length);
            i++;
            off = i * MAX;
        }
        byte[] result = out.toByteArray();
        out.close();
        return result;
    }

以上方法均已验证请放心使用

本文地址：https://blog.csdn.net/u011866450/article/details/107456517