使用AES算法加密SharedPreferences存储
step1
package com.example.mepositry;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.CheckBox;
import android.widget.EditText;
import android.widget.RadioButton;
import android.widget.Toast;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.CheckBox;
import android.widget.EditText;
import android.widget.RadioButton;
import android.widget.Toast;
public class MainActivity extends AppCompatActivity {
private Button button;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.test);
button = findViewById(R.id.button);
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
String name = (String) SharedPreferencesUtils.getParam(MainActivity.this, "username", "");
String pad = (String) SharedPreferencesUtils.getParam(MainActivity.this, "password", "");
try {
String usernameGetString = AESEncryptor.getInstance().decrypt(name);
String padGetString = AESEncryptor.getInstance().decrypt(pad);
Toast.makeText(getApplicationContext(), usernameGetString + "\t" + padGetString, Toast.LENGTH_LONG).show();
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
@Override
protected void onStart() {
super.onStart();
String username = "刘欢";
String pad = "123456";
try {
String usernameSetString = AESEncryptor.getInstance().encrypt(username);
String padSetString = AESEncryptor.getInstance().encrypt(pad);
SharedPreferencesUtils.setParam(this, "username", usernameSetString);
SharedPreferencesUtils.setParam(this, "password", padSetString);
} catch (Exception e) {
e.printStackTrace();
}
}
}
step2:
package com.example.mepositry;
import android.content.Context;
import android.content.SharedPreferences;
import android.preference.PreferenceManager;
import android.util.Base64;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
/**
* SharedPreferences的一个工具类，调用setParam就能保存String, Integer, Boolean, Float, Long类型的参数
* 同样调用getParam就能获取到保存在手机里面的数据
*
* @author xiaanming
*/
public class SharedPreferencesUtils {
/**
* 保存在手机里面的文件名
*/
private static final String FILE_NAME = "share_date";
/**
* 保存数据的方法，我们需要拿到保存数据的具体类型，然后根据类型调用不同的保存方法
*
* @param context
* @param key
* @param object
*/
public static void setParam(Context context, String key, Object object) {
String type = object.getClass().getSimpleName();
SharedPreferences sp = context.getSharedPreferences(FILE_NAME, Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sp.edit();
if ("String".equals(type)) {
editor.putString(key, (String) object);
} else if ("Integer".equals(type)) {
editor.putInt(key, (Integer) object);
} else if ("Boolean".equals(type)) {
editor.putBoolean(key, (Boolean) object);
} else if ("Float".equals(type)) {
editor.putFloat(key, (Float) object);
} else if ("Long".equals(type)) {
editor.putLong(key, (Long) object);
}
editor.commit();
}
/**
* 得到保存数据的方法，我们根据默认值得到保存的数据的具体类型，然后调用相对于的方法获取值
*
* @param context
* @param key
* @param defaultObject
* @return
*/
public static Object getParam(Context context, String key, Object defaultObject) {
String type = defaultObject.getClass().getSimpleName();
SharedPreferences sp = context.getSharedPreferences(FILE_NAME, Context.MODE_PRIVATE);
if ("String".equals(type)) {
return sp.getString(key, (String) defaultObject);
} else if ("Integer".equals(type)) {
return sp.getInt(key, (Integer) defaultObject);
} else if ("Boolean".equals(type)) {
return sp.getBoolean(key, (Boolean) defaultObject);
} else if ("Float".equals(type)) {
return sp.getFloat(key, (Float) defaultObject);
} else if ("Long".equals(type)) {
return sp.getLong(key, (Long) defaultObject);
}
return null;
}
public static boolean setObjectToShare(Context context, Object object,
String key) {
// TODO Auto-generated method stub
SharedPreferences share = PreferenceManager
.getDefaultSharedPreferences(context);
if (object == null) {
SharedPreferences.Editor editor = share.edit().remove(key);
return editor.commit();
}
ByteArrayOutputStream baos = new ByteArrayOutputStream();
ObjectOutputStream oos = null;
try {
oos = new ObjectOutputStream(baos);
oos.writeObject(object);
} catch (IOException e) {
e.printStackTrace();
return false;
}
// 将对象放到OutputStream中
// 将对象转换成byte数组，并将其进行base64编码
String objectStr = new String(Base64.encode(baos.toByteArray(),
Base64.DEFAULT));
try {
baos.close();
oos.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
SharedPreferences.Editor editor = share.edit();
// 将编码后的字符串写到base64.xml文件中
editor.putString(key, objectStr);
return editor.commit();
}
public static Object getObjectFromShare(Context context, String key) {
SharedPreferences sharePre = PreferenceManager
.getDefaultSharedPreferences(context);
try {
String wordBase64 = sharePre.getString(key, "");
// 将base64格式字符串还原成byte数组
if (wordBase64 == null || wordBase64.equals("")) { // 不可少，否则在下面会报java.io.StreamCorruptedException
return null;
}
byte[] objBytes = Base64.decode(wordBase64.getBytes(),
Base64.DEFAULT);
ByteArrayInputStream bais = new ByteArrayInputStream(objBytes);
ObjectInputStream ois = new ObjectInputStream(bais);
// 将byte数组转换成product对象
Object obj = ois.readObject();
bais.close();
ois.close();
return obj;
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
}
step3:
package com.example.mepositry;
import android.text.TextUtils;
import android.util.Log;
import java.io.UnsupportedEncodingException;
import java.security.InvalidAlgorithmParameterException;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.spec.InvalidKeySpecException;
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.PBEKeySpec;
import javax.crypto.spec.SecretKeySpec;
/**
* @author lizihan
* @version V1.0
* @description AES双向加密管控
*/
public class AESEncryptor {
private static final String ENCODING = "UTF-8";
private static AESEncryptor aesEncryptor;
public static AESEncryptor getInstance() {
if (aesEncryptor == null) {
aesEncryptor = new AESEncryptor();
}
return aesEncryptor;
}
public static final String KEY_GENERATION_ALG = "PBKDF2WithHmacSHA1";
private static final int HASH_ITERATIONS = 10000;
private static final int KEY_LENGTH = 256;
private char[] humanPassphrase = {'P', 'e', 'r', ' ', 'v', 'a', 'l', 'l',
'u', 'm', ' ', 'd', 'u', 'c', 'e', 's', ' ', 'L', 'a', 'b', 'a',
'n', 't'};
// char[] humanPassphrase = { 'v', 't', 'i', 'o', 'n','s','f','o','t', '.',
// 'c', 'o', 'm',
// 'p'};
private byte[] salt = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0xA, 0xB, 0xC, 0xD,
0xE, 0xF}; // must save this for next time we want the key
private PBEKeySpec myKeyspec = new PBEKeySpec(humanPassphrase, salt,
HASH_ITERATIONS, KEY_LENGTH);
private static final String CIPHERMODEPADDING = "AES/CBC/PKCS7Padding";
private SecretKeyFactory keyfactory = null;
private SecretKey sk = null;
private SecretKeySpec skforAES = null;
private byte[] iv = {0xA, 1, 0xB, 5, 4, 0xF, 7, 9, 0x17, 3, 1, 6, 8, 0xC,
0xD, 91};
private IvParameterSpec IV;
public AESEncryptor() {
try {
keyfactory = SecretKeyFactory.getInstance(KEY_GENERATION_ALG);
sk = keyfactory.generateSecret(myKeyspec);
} catch (NoSuchAlgorithmException nsae) {
Log.e("AESEncryptor",
"no key factory support for PBEWITHSHAANDTWOFISH-CBC");
} catch (InvalidKeySpecException ikse) {
Log.e("AESEncryptor", "invalid key spec for PBEWITHSHAANDTWOFISH-CBC");
}
// This is our secret key. We could just save this to a file instead of
// regenerating it
// each time it is needed. But that file cannot be on the device (too
// insecure). It could
// be secure if we kept it on a server accessible through https.
byte[] skAsByteArray = sk.getEncoded();
// LogUtil.d("",
// "skAsByteArray=" + skAsByteArray.length + ","
// + Base64Encoder.encode(skAsByteArray));
skforAES = new SecretKeySpec(skAsByteArray, "AES");
IV = new IvParameterSpec(iv);
}
public String encrypt(byte[] plaintext) {
byte[] ciphertext = encrypt(CIPHERMODEPADDING, skforAES, IV, plaintext);
String base64_ciphertext = Base64Encoder.encode(ciphertext);
return base64_ciphertext;
}
public String decrypt(String ciphertext_base64) {
if (TextUtils.isEmpty(ciphertext_base64)) {
return ciphertext_base64;
}
byte[] s = Base64Decoder.decodeToBytes(ciphertext_base64);
String decrypted = new String(decrypt(CIPHERMODEPADDING, skforAES, IV, s));
return decrypted;
}
// Use this method if you want to add the padding manually
// AES deals with messages in blocks of 16 bytes.
// This method looks at the length of the message, and adds bytes at the navi_end
// so that the entire message is a multiple of 16 bytes.
// the padding is a series of bytes, each set to the total bytes added (a
// number in range 1..16).
@SuppressWarnings("unused")
private byte[] addPadding(byte[] plain) {
byte plainpad[] = null;
int shortage = 16 - (plain.length % 16);
// if already an exact multiple of 16, need to add another block of 16
// bytes
if (shortage == 0)
shortage = 16;
// reallocate array bigger to be exact multiple, adding shortage bits.
plainpad = new byte[plain.length + shortage];
for (int i = 0; i < plain.length; i++) {
plainpad[i] = plain[i];
}
for (int i = plain.length; i < plain.length + shortage; i++) {
plainpad[i] = (byte) shortage;
}
return plainpad;
}
// Use this method if you want to remove the padding manually
// This method removes the padding bytes
@SuppressWarnings("unused")
private byte[] dropPadding(byte[] plainpad) {
byte plain[] = null;
int drop = plainpad[plainpad.length - 1]; // last byte gives number of
// bytes to drop
// reallocate array smaller, dropping the pad bytes.
plain = new byte[plainpad.length - drop];
for (int i = 0; i < plain.length; i++) {
plain[i] = plainpad[i];
plainpad[i] = 0; // don't keep a copy of the decrypt
}
return plain;
}
public String encrypt(String content) {
if (TextUtils.isEmpty(content)) {
return content;
}
try {
return encrypt(content.getBytes(ENCODING));
} catch (UnsupportedEncodingException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return "";
}
private byte[] encrypt(String cmp, SecretKey sk, IvParameterSpec IV,
byte[] msg) {
try {
Cipher c = Cipher.getInstance(cmp);
c.init(Cipher.ENCRYPT_MODE, sk, IV);
return c.doFinal(msg);
} catch (NoSuchAlgorithmException nsae) {
Log.e("AESEncryptor", "no cipher getinstance support for " + cmp);
} catch (NoSuchPaddingException nspe) {
Log.e("AESEncryptor", "no cipher getinstance support for padding " + cmp);
} catch (InvalidKeyException e) {
Log.e("AESEncryptor", "invalid key exception");
} catch (InvalidAlgorithmParameterException e) {
Log.e("AESEncryptor", "invalid algorithm parameter exception");
} catch (IllegalBlockSizeException e) {
Log.e("AESEncryptor", "illegal block size exception");
} catch (BadPaddingException e) {
Log.e("AESEncryptor", "bad padding exception");
}
return null;
}
private byte[] decrypt(String cmpstr, SecretKey sk, IvParameterSpec IV, byte[] ciphertext) {
try {
Cipher c = Cipher.getInstance(cmpstr);
c.init(Cipher.DECRYPT_MODE, sk, IV);
return c.doFinal(ciphertext);
} catch (NoSuchAlgorithmException nsae) {
Log.e("AESEncryptor", "no cipher getinstance support for " + cmpstr);
} catch (NoSuchPaddingException nspe) {
Log.e("AESEncryptor", "no cipher getinstance support for padding " + cmpstr);
} catch (InvalidKeyException e) {
Log.e("AESEncryptor", "invalid key exception");
} catch (InvalidAlgorithmParameterException ee) {
Log.e("AESEncryptor", "invalid algorithm parameter exception");
} catch (IllegalBlockSizeException e) {
Log.e("AESEncryptor", "illegal block size exception");
} catch (BadPaddingException e) {
Log.e("AESEncryptor", "bad padding exception");
}
return null;
}
}
step4:
package com.example.mepositry;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.FilterInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.UnsupportedEncodingException;
/**
* @author lizihan
* @version V1.0
* @description 译码器
*/
public class Base64Decoder extends FilterInputStream {
private static final char[] chars = {
'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J',
'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T',
'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd',
'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n',
'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x',
'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7',
'8', '9', '+', '/'
};
// A mapping between char values and six-bit integers
private static final int[] ints = new int[128];
static {
for (int i = 0; i < 64; i++) {
ints[chars[i]] = i;
}
}
private int charCount;
private int carryOver;
/***
* Constructs a new Base64 decoder that reads input from the given
* InputStream.
*
* @param in the input stream
*/
public Base64Decoder(InputStream in) {
super(in);
}
/***
* Returns the next decoded character from the stream, or -1 if
* navi_end of stream was reached.
*
* @return the decoded character, or -1 if the navi_end of the
* input stream is reached
* @throws IOException if an I/O error occurs
*/
public int read() throws IOException {
// Read the next non-whitespace character
int x;
do {
x = in.read();
if (x == -1) {
return -1;
}
} while (Character.isWhitespace((char) x));
charCount++;
// The '=' sign is just padding
if (x == '=') {
return -1; // effective navi_end of stream
}
// Convert from raw form to 6-bit form
x = ints[x];
// Calculate which character we're decoding now
int mode = (charCount - 1) % 4;
// First char save all six bits, go for another
if (mode == 0) {
carryOver = x & 63;
return read();
}
// Second char use previous six bits and first two new bits,
// save last four bits
else if (mode == 1) {
int decoded = ((carryOver << 2) + (x >> 4)) & 255;
carryOver = x & 15;
return decoded;
}
// Third char use previous four bits and first four new bits,
// save last two bits
else if (mode == 2) {
int decoded = ((carryOver << 4) + (x >> 2)) & 255;
carryOver = x & 3;
return decoded;
}
// Fourth char use previous two bits and all six new bits
else if (mode == 3) {
int decoded = ((carryOver << 6) + x) & 255;
return decoded;
}
return -1; // can't actually reach this line
}
/***
* Reads decoded data into an array of bytes and returns the actual
* number of bytes read, or -1 if navi_end of stream was reached.
*
* @param buf the buffer into which the data is read
* @param off the navi_start offset of the data
* @param len the maximum number of bytes to read
* @return the actual number of bytes read, or -1 if the navi_end of the
* input stream is reached
* @throws IOException if an I/O error occurs
*/
public int read(byte[] buf, int off, int len) throws IOException {
if (buf.length < (len + off - 1)) {
throw new IOException("The input buffer is too small: " + len +
" bytes requested starting at offset " + off + " while the buffer " +
" is only " + buf.length + " bytes long.");
}
// This could of course be optimized
int i;
for (i = 0; i < len; i++) {
int x = read();
if (x == -1 && i == 0) { // an immediate -1 returns -1
return -1;
} else if (x == -1) { // a later -1 returns the chars read so far
break;
}
buf[off + i] = (byte) x;
}
return i;
}
/***
* Returns the decoded form of the given encoded string, as a String.
* Note that not all binary data can be represented as a String, so this
* method should only be used for encoded String data. Use decodeToBytes()
* otherwise.
*
* @param encoded the string to decode
* @return the decoded form of the encoded string
*/
public static String decode(String encoded) {
return new String(decodeToBytes(encoded));
}
/***
* Returns the decoded form of the given encoded string, as bytes.
*
* @param encoded the string to decode
* @return the decoded form of the encoded string
*/
public static byte[] decodeToBytes(String encoded) {
byte[] bytes = null;
try {
bytes = encoded.getBytes("UTF-8");
} catch (UnsupportedEncodingException ignored) {
}
if (null == bytes) {
return null;
}
Base64Decoder in = new Base64Decoder(
new ByteArrayInputStream(bytes));
ByteArrayOutputStream out =
new ByteArrayOutputStream((int) (bytes.length * 0.67));
try {
byte[] buf = new byte[4 * 1024]; // 4K buffer
int bytesRead;
while ((bytesRead = in.read(buf)) != -1) {
out.write(buf, 0, bytesRead);
}
out.close();
return out.toByteArray();
} catch (IOException ignored) {
return null;
}
}
// public static void main(String[] args) throws Exception {
// if (args.length != 1) {
// //System.err.println("Usage: java Base64Decoder fileToDecode");
// return;
// }
//
// Base64Decoder decoder = null;
// try {
// decoder = new Base64Decoder(
// new BufferedInputStream(
// new FileInputStream(args[0])));
// byte[] buf = new byte[4 * 1024]; // 4K buffer
// int bytesRead;
// while ((bytesRead = decoder.read(buf)) != -1) {
// System.out.write(buf, 0, bytesRead);
// }
// } finally {
// if (decoder != null) decoder.close_white();
// }
// }
}
step5:
package com.example.mepositry;
import android.util.Log;
import java.io.ByteArrayOutputStream;
import java.io.FilterOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.io.UnsupportedEncodingException;
/**
* @author lizihan
* @version V1.0
* @description 编码器
*/
public class Base64Encoder extends FilterOutputStream {
private static final char[] chars = {
'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J',
'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T',
'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd',
'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n',
'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x',
'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7',
'8', '9', '+', '/'
};
private int charCount;
private int carryOver;
/***
* Constructs a new Base64 encoder that writes output to the given
* OutputStream.
*
* @param out the output stream
*/
public Base64Encoder(OutputStream out) {
super(out);
}
/***
* Writes the given byte to the output stream in an encoded form.
*
* @exception IOException if an I/O error occurs
*/
public void write(int b) throws IOException {
// Take 24-bits from three octets, translate into four encoded chars
// Break lines at 76 chars
// If necessary, pad with 0 bits on the right at the navi_end
// Use = signs as padding at the navi_end to ensure encodedLength % 4 == 0
// Remove the sign bit,
// thanks to Christian Schweingruber <chrigu@lorraine.ch>
if (b < 0) {
b += 256;
}
// First byte use first six bits, save last two bits
if (charCount % 3 == 0) {
int lookup = b >> 2;
carryOver = b & 3; // last two bits
out.write(chars[lookup]);
}
// Second byte use previous two bits and first four new bits,
// save last four bits
else if (charCount % 3 == 1) {
int lookup = ((carryOver << 4) + (b >> 4)) & 63;
carryOver = b & 15; // last four bits
out.write(chars[lookup]);
}
// Third byte use previous four bits and first two new bits,
// then use last six new bits
else if (charCount % 3 == 2) {
int lookup = ((carryOver << 2) + (b >> 6)) & 63;
out.write(chars[lookup]);
lookup = b & 63; // last six bits
out.write(chars[lookup]);
carryOver = 0;
}
charCount++;
// Add newline every 76 output chars (that's 57 input chars)
if (charCount % 57 == 0) {
out.write('\n');
}
}
/***
* Writes the given byte array to the output stream in an
* encoded form.
*
* @param buf the data to be written
* @param off the navi_start offset of the data
* @param len the length of the data
* @exception IOException if an I/O error occurs
*/
public void write(byte[] buf, int off, int len) throws IOException {
// This could of course be optimized
for (int i = 0; i < len; i++) {
write(buf[off + i]);
}
}
/***
* Closes the stream, this MUST be called to ensure proper padding is
* written to the navi_end of the output stream.
*
* @exception IOException if an I/O error occurs
*/
public void close() throws IOException {
// Handle leftover bytes
if (charCount % 3 == 1) { // one leftover
int lookup = (carryOver << 4) & 63;
out.write(chars[lookup]);
out.write('=');
out.write('=');
} else if (charCount % 3 == 2) { // two leftovers
int lookup = (carryOver << 2) & 63;
out.write(chars[lookup]);
out.write('=');
}
super.close();
}
/***
* Returns the encoded form of the given unencoded string. The encoder
* uses the ISO-8859-1 (Latin-1) encoding to convert the string to bytes.
* For greater control over the encoding, encode the string to bytes
* yourself and use encode(byte[]).
*
* @param unencoded the string to encode
* @return the encoded form of the unencoded string
*/
public static String encode(String unencoded) {
byte[] bytes = null;
try {
bytes = unencoded.getBytes("UTF-8");
} catch (UnsupportedEncodingException ignored) {
Log.d("zyx", " UnsupportedEncodingException ignored");
}
return encode(bytes);
}
/***
* Returns the encoded form of the given unencoded string.
*
* @param bytes the bytes to encode
* @return the encoded form of the unencoded string
*/
public static String encode(byte[] bytes) {
ByteArrayOutputStream out =
new ByteArrayOutputStream((int) (bytes.length * 1.37));
Base64Encoder encodedOut = new Base64Encoder(out);
try {
encodedOut.write(bytes);
encodedOut.close();
return out.toString("UTF-8");
} catch (IOException ignored) {
return null;
}
}
// public static void main(String[] args) throws Exception {
// if (args.length != 1) {
//// System.err.println(
//// "Usage: java com.oreilly.servlet.Base64Encoder fileToEncode");
// return;
// }
//
// Base64Encoder encoder = null;
// BufferedInputStream in = null;
// try {
// encoder = new Base64Encoder(System.out);
// in = new BufferedInputStream(new FileInputStream(args[0]));
//
// byte[] buf = new byte[4 * 1024]; // 4K buffer
// int bytesRead;
// while ((bytesRead = in.read(buf)) != -1) {
// encoder.write(buf, 0, bytesRead);
// }
// } finally {
// if (in != null) in.close_white();
// if (encoder != null) encoder.close_white();
// }
// }
}
run 运行项目，点击button，查看解密是否成功
？？？ 如何查看加密的字段呢
step1 : 选择Android studio 顶部栏
依次选择 view => tool windows => device file explorer
此时右侧有一个弹窗，
step2: 依次选择
data=> data => <你的项目package包名> => shared_prefs => share_date.xml 打开此文件，如果看到存储的数据为密文，表示加密成功，在你需要读取共享参数的地方进行解密，查看解密结果，如果是存储结果一致，表示解密成功 end
