/*
 * Copyright 2015 The Error Prone Authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.google.errorprone.bugpatterns.testdata;

import java.security.KeyFactory;
import java.security.KeyPairGenerator;
import java.security.NoSuchAlgorithmException;
import java.security.NoSuchProviderException;
import javax.crypto.Cipher;
import javax.crypto.KeyAgreement;
import javax.crypto.NoSuchPaddingException;

/**
 * @author avenet@google.com (Arnaud J. Venet)
 */
public class InsecureCipherModePositiveCases {
  static Cipher defaultAesCipher;

  static {
    try {
      // BUG: Diagnostic contains: the mode and padding must be explicitly specified
      defaultAesCipher = Cipher.getInstance("AES");
    } catch (NoSuchAlgorithmException e) {
      // We don't handle any exception as this code is not meant to be executed.
    } catch (NoSuchPaddingException e) {
      // We don't handle any exception as this code is not meant to be executed.
    }
  }

  static Cipher defaultRsaCipher;

  static {
    try {
      // BUG: Diagnostic contains: the mode and padding must be explicitly specified
      defaultRsaCipher = Cipher.getInstance("RSA");
    } catch (NoSuchAlgorithmException e) {
      // We don't handle any exception as this code is not meant to be executed.
    } catch (NoSuchPaddingException e) {
      // We don't handle any exception as this code is not meant to be executed.
    }
  }

  static final String AES_STRING = "AES";
  static Cipher defaultAesCipherWithConstantString;

  static {
    try {
      // BUG: Diagnostic contains: the mode and padding must be explicitly specified
      defaultAesCipherWithConstantString = Cipher.getInstance(AES_STRING);
    } catch (NoSuchAlgorithmException e) {
      // We don't handle any exception as this code is not meant to be executed.
    } catch (NoSuchPaddingException e) {
      // We don't handle any exception as this code is not meant to be executed.
    }
  }

  static Cipher explicitAesCipher;

  static {
    try {
      // BUG: Diagnostic contains: ECB mode must not be used
      explicitAesCipher = Cipher.getInstance("AES/ECB/NoPadding");
    } catch (NoSuchAlgorithmException e) {
      // We don't handle any exception as this code is not meant to be executed.
    } catch (NoSuchPaddingException e) {
      // We don't handle any exception as this code is not meant to be executed.
    }
  }

  static Cipher explicitDesCipher;

  static {
    try {
      // BUG: Diagnostic contains: ECB mode must not be used
      explicitDesCipher = Cipher.getInstance("DES/ECB/NoPadding");
    } catch (NoSuchAlgorithmException e) {
      // We don't handle any exception as this code is not meant to be executed.
    } catch (NoSuchPaddingException e) {
      // We don't handle any exception as this code is not meant to be executed.
    }
  }

  static Cipher explicitDesCipherWithProvider;

  static {
    try {
      // BUG: Diagnostic contains: ECB mode must not be used
      explicitDesCipherWithProvider = Cipher.getInstance("DES/ECB/NoPadding", "My Provider");
    } catch (NoSuchAlgorithmException e) {
      // We don't handle any exception as this code is not meant to be executed.
    } catch (NoSuchPaddingException e) {
      // We don't handle any exception as this code is not meant to be executed.
    } catch (NoSuchProviderException e) {
      // We don't handle any exception as this code is not meant to be executed.
    }
  }

  static String transformation;

  static {
    try {
      transformation = "DES/CBC/NoPadding";
      // BUG: Diagnostic contains: the transformation is not a compile-time constant
      Cipher cipher = Cipher.getInstance(transformation);
    } catch (NoSuchAlgorithmException e) {
      // We don't handle any exception as this code is not meant to be executed.
    } catch (NoSuchPaddingException e) {
      // We don't handle any exception as this code is not meant to be executed.
    }
  }

  static void transformationAsParameter(String transformation) {
    try {
      // BUG: Diagnostic contains: the transformation is not a compile-time constant
      Cipher cipher = Cipher.getInstance(transformation);
    } catch (NoSuchAlgorithmException e) {
      // We don't handle any exception as this code is not meant to be executed.
    } catch (NoSuchPaddingException e) {
      // We don't handle any exception as this code is not meant to be executed.
    }
  }

  class CipherWrapper {
    Cipher cipher;

    // Make sure that the checker is enabled inside constructors.
    public CipherWrapper() {
      try {
        // BUG: Diagnostic contains: the mode and padding must be explicitly specified
        cipher = Cipher.getInstance("AES");
      } catch (NoSuchAlgorithmException e) {
        // We don't handle any exception as this code is not meant to be executed.
      } catch (NoSuchPaddingException e) {
        // We don't handle any exception as this code is not meant to be executed.
      }
    }
  }

  static Cipher complexCipher1;

  static {
    try {
      String algorithm = "AES";
      // BUG: Diagnostic contains: the transformation is not a compile-time constant
      complexCipher1 = Cipher.getInstance(algorithm);
    } catch (NoSuchAlgorithmException e) {
      // We don't handle any exception as this code is not meant to be executed.
    } catch (NoSuchPaddingException e) {
      // We don't handle any exception as this code is not meant to be executed.
    }
  }

  static Cipher complexCipher2;

  static {
    try {
      String transformation = "AES";
      transformation += "/ECB";
      transformation += "/NoPadding";
      // BUG: Diagnostic contains: the transformation is not a compile-time constant
      complexCipher2 = Cipher.getInstance(transformation);
    } catch (NoSuchAlgorithmException e) {
      // We don't handle any exception as this code is not meant to be executed.
    } catch (NoSuchPaddingException e) {
      // We don't handle any exception as this code is not meant to be executed.
    }
  }

  static Cipher IesCipher;

  static {
    try {
      // BUG: Diagnostic contains: the mode and padding must be explicitly specified
      IesCipher = Cipher.getInstance("ECIES");
      // BUG: Diagnostic contains: IES
      IesCipher = Cipher.getInstance("ECIES/DHAES/NoPadding");
      // BUG: Diagnostic contains: IES
      IesCipher = Cipher.getInstance("ECIESWITHAES/NONE/PKCS5Padding");
      // BUG: Diagnostic contains: IES
      IesCipher = Cipher.getInstance("DHIESWITHAES/DHAES/PKCS7Padding");
      // BUG: Diagnostic contains: IES
      IesCipher = Cipher.getInstance("ECIESWITHDESEDE/NONE/NOPADDING");
      // BUG: Diagnostic contains: IES
      IesCipher = Cipher.getInstance("DHIESWITHDESEDE/DHAES/PKCS5PADDING");
      // BUG: Diagnostic contains: IES
      IesCipher = Cipher.getInstance("ECIESWITHAES/CBC/PKCS7PADDING");
      // BUG: Diagnostic contains: IES
      IesCipher = Cipher.getInstance("ECIESWITHAES-CBC/NONE/PKCS5PADDING");
      // BUG: Diagnostic contains: IES
      IesCipher = Cipher.getInstance("ECIESwithDESEDE-CBC/DHAES/NOPADDING");

    } catch (NoSuchAlgorithmException e) {
      // We don't handle any exception as this code is not meant to be executed.
    } catch (NoSuchPaddingException e) {
      // We don't handle any exception as this code is not meant to be executed.
    }
  }

  interface StringProvider {
    String get();
  }

  public void keyOperations(StringProvider provider) {
    KeyFactory keyFactory;
    KeyAgreement keyAgreement;
    KeyPairGenerator keyPairGenerator;
    final String dh = "DH";
    try {
      // BUG: Diagnostic contains: compile-time constant
      keyFactory = KeyFactory.getInstance(provider.get());
      // BUG: Diagnostic contains: Diffie-Hellman on prime fields
      keyFactory = KeyFactory.getInstance(dh);
      // BUG: Diagnostic contains: DSA
      keyAgreement = KeyAgreement.getInstance("DSA");
      // BUG: Diagnostic contains: compile-time constant
      keyAgreement = KeyAgreement.getInstance(provider.get());
      // BUG: Diagnostic contains: Diffie-Hellman on prime fields
      keyPairGenerator = KeyPairGenerator.getInstance(dh);
      // BUG: Diagnostic contains: compile-time constant
      keyPairGenerator = KeyPairGenerator.getInstance(provider.get());
    } catch (NoSuchAlgorithmException e) {
      // We don't handle any exception as this code is not meant to be executed.
    }
  }
}
