Android 上的公钥加密

Question

我知道有这样的代码： http://www.java2s.com/Code/Android/Security/RSAencryptdecryptfunctionRSAECBPKCS1Padding.htm

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//package org.andlib.helpers;
public static KeyPair generateRsaKeyPair(int keySize, BigInteger publicExponent)
{
KeyPair keys = null;
try
{
  KeyPairGenerator keyGen = KeyPairGenerator.getInstance("RSA");
  RSAKeyGenParameterSpec spec = new RSAKeyGenParameterSpec(keySize, publicExponent);
  keyGen.initialize(spec);
  keys = keyGen.generateKeyPair();
}
catch(Exception e)
{
//  Logger.e(e.toString());
}
return keys;


}



/**
   * generates a RSA public key with given modulus and public exponent
   * 
   * @param modulus (must be positive? don't know exactly)
   * @param publicExponent
   * @return
   */
  public static PublicKey generateRsaPublicKey(BigInteger modulus, BigInteger publicExponent)
  {
    try
    {
      return KeyFactory.getInstance("RSA").generatePublic(new RSAPublicKeySpec(modulus,     publicExponent));
    }
    catch(Exception e)
    {
    //  Logger.e(e.toString());
    }
    return null;
  }

  /**
   * generates a RSA private key with given modulus and private exponent
   * 
   * @param modulus (must be positive? don't know exactly)
   * @param privateExponent
   * @return
   */
  public static PrivateKey generateRsaPrivateKey(BigInteger modulus, BigInteger privateExponent)
  {
    try
    {
      return KeyFactory.getInstance("RSA").generatePrivate(new RSAPrivateKeySpec(modulus, privateExponent));
    }
    catch(Exception e)
    {
    //  Logger.e(e.toString());
    }
    return null;
  }

  /**
   * RSA encrypt function (RSA / ECB / PKCS1-Padding)
   * 
   * @param original
   * @param key
   * @return
   */
  public static byte[] rsaEncrypt(byte[] original, PublicKey key)
  {
    try
    {
      Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
      cipher.init(Cipher.ENCRYPT_MODE, key);
      return cipher.doFinal(original);
    }
    catch(Exception e)
    {
    //  Logger.e(e.toString());
    }
    return null;
  }

  /**
   * RSA decrypt function (RSA / ECB / PKCS1-Padding)
   * 
   * @param encrypted
   * @param key
   * @return
   */
  public static byte[] rsaDecrypt(byte[] encrypted, PrivateKey key)
  {
    try
    {
      Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
      cipher.init(Cipher.DECRYPT_MODE, key);
      return cipher.doFinal(encrypted);
    }
    catch(Exception e)
    {
    //  Logger.e(e.toString());
    }
    return null;
  }

一些问题：

上面链接的代码是否存在侧面攻击，或者它是否安全？

如果第一个问题的答案是否定的，那么是否有一个模块可以处理侧向攻击？

我正在使用 Froyo 并且已经尝试了一段时间的谷歌搜索。感谢所有帮助，谢谢。

Answer 1

“侧面攻击”是什么意思？它是否安全取决于很多事情，主要取决于你如何使用它，以及你在加密/解密什么。有趣的是，许可证比代码长，而代码基本上没有什么特别之处：只是吞下异常......

这与Android无关，顺便说一句。