Android Open Source - SamplePaymentProject Key Handler

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License

The source code is released under:

Apache License

Java Source Code

package ch.uzh.csg.samplepaymentproject;
/*  w  ww .  ja va2 s  .  c  om*/
import java.security.InvalidAlgorithmParameterException;
import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.NoSuchAlgorithmException;
import java.security.NoSuchProviderException;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.SecureRandom;
import java.security.Security;
import java.security.spec.EncodedKeySpec;
import java.security.spec.InvalidKeySpecException;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;

import org.spongycastle.jce.ECNamedCurveTable;
import org.spongycastle.jce.provider.BouncyCastleProvider;
import org.spongycastle.jce.spec.ECParameterSpec;

import android.util.Base64;
import ch.uzh.csg.mbps.customserialization.PKIAlgorithm;
import ch.uzh.csg.mbps.customserialization.exceptions.UnknownPKIAlgorithmException;

public class KeyHandler {

  private static final String SECURITY_PROVIDER = "SC";
  
  static {
    Security.addProvider(new BouncyCastleProvider());
  }
  
  public static KeyPair generateKeyPair() throws UnknownPKIAlgorithmException, NoSuchAlgorithmException,
      NoSuchProviderException, InvalidAlgorithmParameterException {
      return generateKeyPair(PKIAlgorithm.DEFAULT);
  }

  public static KeyPair generateKeyPair(PKIAlgorithm algorithm) throws UnknownPKIAlgorithmException,
          NoSuchAlgorithmException, NoSuchProviderException, InvalidAlgorithmParameterException {
    if (algorithm.getCode() != PKIAlgorithm.DEFAULT.getCode())
      throw new UnknownPKIAlgorithmException();

    ECParameterSpec ecSpec = ECNamedCurveTable.getParameterSpec(algorithm.getKeyPairSpecification());
    KeyPairGenerator keyGen = KeyPairGenerator.getInstance(algorithm.getKeyPairAlgorithm(), SECURITY_PROVIDER);
    keyGen.initialize(ecSpec, new SecureRandom());
    return keyGen.generateKeyPair();
  }
  
  public static PublicKey decodePublicKey(String publicKeyEncoded) throws UnknownPKIAlgorithmException, NoSuchAlgorithmException, NoSuchProviderException, InvalidKeySpecException {
    return decodePublicKey(publicKeyEncoded, PKIAlgorithm.DEFAULT);
  }

  public static PublicKey decodePublicKey(String publicKeyEncoded, PKIAlgorithm algorithm) throws UnknownPKIAlgorithmException, NoSuchAlgorithmException, NoSuchProviderException, InvalidKeySpecException {
    if (algorithm.getCode() != PKIAlgorithm.DEFAULT.getCode())
      throw new UnknownPKIAlgorithmException();
    
    byte[] decoded = Base64.decode(publicKeyEncoded.getBytes(), Base64.DEFAULT);
    EncodedKeySpec publicKeySpec = new X509EncodedKeySpec(decoded);
    
    KeyFactory keyFactory = KeyFactory.getInstance(algorithm.getKeyPairAlgorithm(), SECURITY_PROVIDER);
    return keyFactory.generatePublic(publicKeySpec);
  }
  
  public static PrivateKey decodePrivateKey(String privateKeyEncoded) throws UnknownPKIAlgorithmException, NoSuchAlgorithmException, NoSuchProviderException, InvalidKeySpecException {
    return decodePrivateKey(privateKeyEncoded, PKIAlgorithm.DEFAULT);
  }
  
  public static PrivateKey decodePrivateKey(String privateKeyEncoded, PKIAlgorithm algorithm) throws UnknownPKIAlgorithmException, NoSuchAlgorithmException, NoSuchProviderException, InvalidKeySpecException {
    if (algorithm.getCode() != PKIAlgorithm.DEFAULT.getCode())
      throw new UnknownPKIAlgorithmException();
    
    byte[] decoded = Base64.decode(privateKeyEncoded.getBytes(), Base64.DEFAULT);
    EncodedKeySpec privateKeySpec = new PKCS8EncodedKeySpec(decoded);
    
    KeyFactory keyFactory = KeyFactory.getInstance(algorithm.getKeyPairAlgorithm(), SECURITY_PROVIDER);
    return keyFactory.generatePrivate(privateKeySpec);
  }
  
}

Java Source Code List

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