Question

我搜索了很多，但我找不到有用的答案。我开发java和android安全应用程序。我发现一些问题，当我在PC上创建RSA密钥并将RSA公钥传输到android时。当我使用Android上的公钥加密我的数据并使用PC上的私钥解密数据时，它显示Badpadding Exception。我在谷歌搜索此例外。我发现一些用户对我有同样的问题，但答案是没有用的。他们告诉我使用Base64对它进行编码，但关键仍然是错误的。这是我的代码。

 public void generateKeys(){
    try {
        KeyPairGenerator generator;
        generator = KeyPairGenerator.getInstance("RSA");
        generator.initialize(1024, new SecureRandom());
        KeyPair pair = generator.generateKeyPair();

        pubKey = pair.getPublic();
        privKey = pair.getPrivate();
        //================================================
       System.out.println("My Public KEY "+pubKey.toString());
         System.out.println("My Private KEY "+privKey.toString());

        byte[]pk_byte = pubKey.getEncoded();
        byte[]sk_byte = privKey.getEncoded();

            FileOutputStream keyfos_pub = new FileOutputStream(new File(Environment.getExternalStorageDirectory(),"RSAKey/publicKey.txt"));
            keyfos_pub.write(pk_byte);
            keyfos_pub.close();

            FileOutputStream keyfos_pri = new FileOutputStream(new File(Environment.getExternalStorageDirectory(),"RSAKey/privateKey.txt"));
            keyfos_pri.write(sk_byte);
            keyfos_pri.close();
        } catch (FileNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (NoSuchAlgorithmException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } 

}

当我打印出钥匙时，它看起来像这样。

RSA Private CRT Key
            modulus: dba017a7653612c53f3a46bb99f5098c7bf9012d06f3d20f8f01a67d17aeefd83070a2ff181468679a2d5abae6f7c074b7b3888a4a57533acc3d2d1dfdd86cdc032d3eafd6cf8423edfa3451333bf1d7377352dd3feb9268032831abd72c5c932fed9b4c667f3da062f4beb7a321f2c434d232ee746885dce13a1656eb42fe6b
    public exponent: 10001
   private exponent: 72f10f5019653a5fa6de9e0432e80e4e4ad79fe8ebd99157793598e7a10c7a14000e0310548ee1b14efc6b9ea3a08845cd9a955c22da1f0207c000abd09d83228e05a42f9bd88733afc2a4c1e30770e7ac3c41c55adae734e4f8126da494a88f362d716d6b37a2d7bfbe53824cfb9dc7a0289aa432226bbece49129f47de2a61
             primeP: efa2665a1e08dce4450ad608e17df1e3650ab2cfc44e9b3b6a346611b270b245e21c28f71971d5062368e66b99297085f23104577e529ef08b263e63387cf17b
             primeQ: ea9fde740a15d7f68f5aadb72a588f65da3761119b0c73930f111a43d513d19f42185afcd0291f03a9861a7757108f0e83d4d904ddf541a2debd79344387bbd1
     primeExponentP: 45202ab84a3bb244a2e9fa4dfb861235cf5ae3b3ed63e381a32454613c8127dbe2daceb26103a638ac14418bbe55e6e0acb99910081f9b3bb65824dd08597a6b
     primeExponentQ: 53ca665a90a37e6e1a822ad9e8309a7da871f0a3a5f8cb69b08ece0f7d90476395ea36cc64d6dab1a72032617e6176859b852f3ff2b8bd091a7d164518fce791
     crtCoefficient: 695a3707d033aa2474a7a64959589842099a220540167b48f42bbbd1d786d1a84c378f9a1bc0311948287cbf7669aa44156dd9f24bfe88baf931e5da70a06c4

RSA Public Key
            modulus: dba017a7653612c53f3a46bb99f5098c7bf9012d06f3d20f8f01a67d17aeefd83070a2ff181468679a2d5abae6f7c074b7b3888a4a57533acc3d2d1dfdd86cdc032d3eafd6cf8423edfa3451333bf1d7377352dd3feb9268032831abd72c5c932fed9b4c667f3da062f4beb7a321f2c434d232ee746885dce13a1656eb42fe6b
    public exponent: 10001

我把钥匙发送到PC并打印出来就像这样

Sun RSA private CRT key, 1024 bits
  modulus:          133510687177139403090984227659818165988216147752229771757259279456909046924729578431711819486905574365970242930474912203422914618872480707080105400973005394104312017850522474151319747965391515392091886771183127658574637486403332621957057719375091145573274843838361168501101321026667287976397870949812555235301
  public exponent:  65537
  private exponent: 9980146428442039393666657480590341260299844482325612277626580558453963728645653672535456363067433797990268399780224833064816191126482490562360748269935354262219600344146818595176602910809143102802601846580823241077395526479491554799584457750285244532837191028964347562514222968145677820868899082320352227173
  prime p:          12299841631131712301068734715117232218530765196368758184959862403767638338760002562429845237522849739220962134079733702092483313582445665328865919334315231
  prime q:          10854667172235374767842313747899047475769598966944705527971116954964144369647441254504149073040778536441723902849901407264741891511747045046848533162966971
  prime exponent p: 9681923647204217071082501281466465900019303827612974308340469989251337818636053102684450861548877311242977166683023364260601327205871598989662862911311993
  prime exponent q: 1654443602597908945419791446477006656323336803344838236704510234877044083623118096514059921732827819407607611968318128037101282547428799502158627916518563
  crt coefficient:  8339065711012644104593134475846199184972354402766421557421676186133596071951423663692155855342215056476322973047333984032026031966395156454879551656339085

很明显，密钥已更改，因为密钥中出现“1024位”字样，而且modulas的数量不一样

如何管理此问题。我想请专业人士帮助我

Answer 1

这看起来像一个不同的关键。请再试一次，因为您可能会发送旧密钥或其他内容。确保您不会重新生成密钥对，每次都会有所不同。使用私钥将模数打印为BigInteger; BigInteger个实例将始终打印为小数，以便于比较。或者甚至更好，使用BigInteger.toString(16)来获得十六进制表示。

如果你使用一个好的随机数生成器（比如Java中的默认生成器）那么模数对于密钥对应该是唯一的。因此，它或模数上的SHA1哈希值通常用于标识密钥。

Answer 2

它们是相同的东西，但是Android以16（十六进制）的形式打印出来，而桌面的Java则用10（十进制）打印它。您会看到不同实现之间toString()输出的变体。

例如，查看公共指数并注意十六进制0x10001等于十进制65537。该指数通常称为RSA F4。但是，由于此公共指数用于许多键，因此无法使用它来区分键。

Android上的RSA与PC不同

2 个答案: