Main.java Source code

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Here is the source code for Main.java

Source

//package com.java2s;
/*
 * 
 * Copyright (C) 2015 Orange Labs
 * 
 * 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.
 * 
 */

import java.nio.ByteBuffer;

import java.util.Arrays;

import javax.crypto.Mac;

import javax.crypto.spec.SecretKeySpec;
import android.util.Base64;

public class Main {
    public static String completeJweFromSIM(String jweSIM) {
        // android.os.Debug.waitForDebugger();

        try {
            if (jweSIM != null && jweSIM.length() > 0) {
                String parts[] = jweSIM.split("\\.");
                ;
                if (parts != null && parts.length == 5) {
                    // retrieve hmac key
                    byte hmac_key[] = Base64.decode(parts[4], Base64.URL_SAFE);
                    if (hmac_key != null && hmac_key.length == 16) {
                        // init hash instance
                        Mac hmac = Mac.getInstance("HmacSHA256", "SC");
                        hmac.init(new SecretKeySpec(hmac_key, "HmacSHA256"));

                        byte[] aad = parts[0].getBytes();
                        long al = aad.length * 8;
                        byte[] iv_key = decodeB64(parts[2]);
                        byte[] cryptedBytes = decodeB64(parts[3]);

                        // build data to hash
                        byte[] hmacData = new byte[aad.length + iv_key.length + cryptedBytes.length + 8];
                        int offset = 0;
                        System.arraycopy(aad, offset, hmacData, 0, aad.length);
                        offset += aad.length;
                        System.arraycopy(iv_key, 0, hmacData, offset, iv_key.length);
                        offset += iv_key.length;
                        System.arraycopy(cryptedBytes, 0, hmacData, offset, cryptedBytes.length);
                        offset += cryptedBytes.length;
                        ByteBuffer buffer = ByteBuffer.allocate(8);
                        buffer.putLong(al);
                        System.arraycopy(buffer.array(), 0, hmacData, offset, 8);

                        // compute hac value
                        byte[] hmacValue = hmac.doFinal(hmacData);
                        // authentication tag
                        byte[] auth_tag = Arrays.copyOf(hmacValue, 16);
                        String auth_tag64 = encodeB64(auth_tag);

                        // A.2.7. Complete Representation
                        String finalString = parts[0] + "." + parts[1] + "." + parts[2] + "." + parts[3] + "."
                                + auth_tag64;

                        //                  // just for verification
                        //                  byte jwt64 [] = decryptJWE(finalString, RsaKeyTim.privRsaKey);
                        //                  if(jwt64!=null) {
                        //                     String jws = new String(jwt64);
                        //                     Log.d("completeJweFromSIM", "jws verify Key TIM :"+verifyJWS(jws,RsaKeyTim.pubRsaKey));
                        //                  }

                        return finalString;
                    }
                }
                // 
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

    static byte[] decodeB64(String s64) {
        return Base64.decode(s64, Base64.URL_SAFE);
    }

    static String encodeB64(byte[] bytes) {
        try {
            return Base64.encodeToString(bytes, Base64.URL_SAFE | Base64.NO_PADDING | Base64.NO_WRAP);
        } catch (Exception e) {
        }
        return null;
    }
}