安卓 assets配置檔案加密
阿新 • • 發佈：2018-12-17
安卓應用的中配置檔案資訊，為了防止篡改，一般不以明文的形式進行儲存。
配置資訊示例：
配置加密後：
程式碼中配置資訊的讀取：
import java.io.InputStream; import java.io.InputStreamReader; import java.util.Properties; import android.content.Context; import android.util.Log; /** AssetProperty.java: 讀取assets目錄中的配置檔案資訊----- 2018-2-27 下午8:08:10 scimence */ public class AssetProperty { // 示例： private void Example() { // assets目錄下的檔案如： assets/payconfig.txt // #檔案內容： // ShowAlipay=true // ShowWeChat=true AssetProperty config = new AssetProperty(context, "payconfig.txt"); String ShowAlipay = config.getConfig("ShowAlipay", "true"); // 讀取配置資訊 // 備註：直接在檔案目錄下新增檔案，getAssets().open()可能會報錯： java.io.FileNotFoundException: payconfig.txt // 在assets中新增配置檔案，需選中assets資料夾（右鍵）-> New -> File -> 輸入檔名（payconfig.txt）-> Finish } // ------------------------------- String filepath = ""; // assets目錄下的檔案如： assets/payconfig.txt Context context; Properties prop = null; /** 建立AssetProperty */ public AssetProperty(Context context, String filepath) { this.context = context; this.filepath = filepath; // if (prop == null) prop = getAssetsProperty(context, filepath); if (prop == null) prop = getAssetsPropertyEncrypt(context, filepath); } /** 讀取AssetProperty中的配置資訊 */ public String getConfig(String name, String defval) { if (prop == null) return defval; else return prop.getProperty(name, defval); } /** 讀取Assest資料夾下資源，返回Properties */ public static Properties getAssetsProperty(Context context, String filepath) { try { Properties prop = new Properties(); InputStreamReader reader = new InputStreamReader(context.getAssets().open(filepath), "UTF-8"); prop.load(reader); reader.close(); return prop; } catch (Exception e) { Log.e("AssetProperty", e.toString()); } return null; } /** 讀取Assest資料夾下資源，返回Properties。若為加密資料則自動解密 */ public static Properties getAssetsPropertyEncrypt(Context context, String filepath) { try { // 讀取assets資料 InputStream inputStream = context.getAssets().open(filepath); String data = TypeTool.InputStreamToString(inputStream); inputStream.close(); // assets資料解密邏輯 if (Encrypt.isEncrypt(data)) data = Encrypt.Encryption(data.substring(5), -65537); // 解密資料 // ByteArrayInputStream in = new ByteArrayInputStream(data.getBytes()); // InputStreamReader reader = new InputStreamReader(in); InputStreamReader reader = TypeTool.StringToInputStreamReader(data); Properties prop = new Properties(); prop.load(reader); reader.close(); return prop; } catch (Exception e) { Log.e("AssetProperty", e.toString()); } return null; } }
TypeTool.java
package com.ltsdk.thumbsup.funchtion; import java.io.ByteArrayInputStream; import java.io.ByteArrayOutputStream; import java.io.InputStream; import java.io.InputStreamReader; /** TypeTool.java:資料型別相互轉化工具類 ----- 2018-10-23 上午10:08:54 scimence */ public class TypeTool { /** Byte -> String */ public static String ByteToString(byte[] bytes) { return new String(bytes); } /** String -> Byte */ public static byte[] StringToByte(String data) { return data.getBytes(); } /** Byte -> InputStream */ public static final InputStream ByteToInputStream(byte[] bytes) { return new ByteArrayInputStream(bytes); } /** InputStream -> Byte */ public static final byte[] InputStreamToByte(InputStream in) { byte[] bytes = {}; try { ByteArrayOutputStream byteOutStream = new ByteArrayOutputStream(); byte[] data = new byte[1024]; int count = 0; while ((count = in.read(data, 0, 1024)) > 0) { byteOutStream.write(data, 0, count); } bytes = byteOutStream.toByteArray(); } catch (Exception ex) { ex.printStackTrace(); } return bytes; } /** InputStream -> String */ public static String InputStreamToString(InputStream in) { String data = ""; byte[] bytes = InputStreamToByte(in); data = new String(bytes); return data; } /** String -> InputStream */ public static InputStream StringToInputStream(String data) { byte[] bytes = data.getBytes(); InputStream inputstream = ByteToInputStream(bytes); return inputstream; } /** String -> InputStreamReader */ public static InputStreamReader StringToInputStreamReader(String data) { byte[] bytes = data.getBytes(); InputStream inputstream = ByteToInputStream(bytes); InputStreamReader reader = new InputStreamReader(inputstream); return reader; } }
Encrypt.java
package sci.tools; /** Encrypt.java: 對字串或檔案進行自定義加解密。 * 加密字串：Encryption(String str, int change) * 解密字串：Encryption(String str, int -change) * 加密byte陣列：Encryption(byte[] bytes, int change) * 解密byte陣列：Encryption(byte[] bytes, int -change) * ----- 2018-10-22 下午5:50:35 scimence */ public class Encrypt { /** 對字串資料進行加解密， change加密、 -chage解密 */ public static String Encryption(String str, int change) { if ((str.equals("")) || (str == null)) return ""; byte[] bytes; if (change < 0) bytes = toBytes(str); else bytes = str.getBytes(); Encryption(bytes, change); if (change < 0) str = new String(bytes); else str = toHex(bytes); return str; } /** 對bytes資料進行加密、解密操作， change加密、 -chage解密 */ public static void Encryption(byte[] bytes, int change) { short sign = 1; if (change < 0) { sign = -1; change *= -1; } int num = 0; for (int i = 0; i < bytes.length; i++) { if (num == 0) num = change; int tmp = bytes[i] + sign * (num % 3); if (tmp > 127) tmp -= 255; else if (tmp < -128) tmp += 255; bytes[i] = ((byte) tmp); num /= 3; } } private static String toHex(byte[] B) { String tmp = ""; byte[] arrayOfByte = B; int j = B.length; for (int i = 0; i < j; i++) { byte b = arrayOfByte[i]; tmp = tmp + toHex(b); } return tmp; } private static byte[] toBytes(String Hex) { byte[] B = new byte[Hex.length() / 2]; for (int i = 0; i + 1 < Hex.length(); i += 2) { String hexStr = Hex.substring(i, i + 2); B[(i / 2)] = toByte(hexStr); } return B; } private static String toHex(byte B) { int N = B + 128; return "" + (char) (65 + N / 26) + (char) (65 + N % 26); } private static byte toByte(String Hex) { int N = (Hex.charAt(0) - 'A') * 26 + (Hex.charAt(1) - 'A'); return (byte) (N - 128); } /** 判斷資料是否為加密的資料 */ public static boolean isEncrypt(String data) { return data.startsWith("DATA$"); } }