Android 传递 IV 参数加密/解密文本
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【中文标题】Android 传递 IV 参数加密/解密文本【英文标题】：Android Passing IV parameters Encryption /Decryption text 【发布时间】：2021-11-06 20:27:58 【问题描述】：我希望你能帮助我关联我的代码。
我正在尝试将参数 IV 传递给加密/解密
加密函数：
我尝试连接文本；四
encryptedText.setText(Base64.encodeToString(vals, Base64.DEFAULT) + ";" + (Base64.encodeToString(encryptionIv, Base64.DEFAULT)));
我认为效果很好，如图所示。
public void encryptString(String alias)
try
KeyStore keyStore = KeyStore.getInstance("androidKeyStore");
keyStore.load(null);
SecretKey secretKey = (SecretKey) keyStore.getKey(alias, null);
String initialText = startText.getText().toString();
if(initialText.isEmpty())
Toast.makeText(this, "Enter text in the 'Initial Text'", Toast.LENGTH_LONG).show();
return;
Cipher inCipher = Cipher.getInstance("AES/GCM/NoPadding");
inCipher.init(Cipher.ENCRYPT_MODE, secretKey);
byte[] src= initialText.getBytes("UTF-8");
byte[] iv = inCipher.getIV();
assert iv.length == 12;
byte[] cipherText = inCipher.doFinal(src);
assert cipherText.length == src.length + 16;
byte[] message = new byte[12 + src.length + 16];
ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
CipherOutputStream cipherOutputStream = new CipherOutputStream(
outputStream, inCipher);
cipherOutputStream.write(src);
cipherOutputStream.close();
byte [] vals = outputStream.toByteArray();
encryptedText.setText(Base64.encodeToString(vals, Base64.DEFAULT));
catch (Exception e)
Toast.makeText(this, "Exception " + e.getMessage() + " occurred", Toast.LENGTH_LONG).show();
Log.e(TAG, Log.getStackTraceString(e));
[![在此处输入图像描述][1]][1] 你能帮我举个例子来让解密工作正常吗？
谢谢你的帮助
更新：你好，我试图通过IV作为例子：
我的代码在这里：
public void encryptString(String alias)
try
KeyStore.PrivateKeyEntry privateKeyEntry = (KeyStore.PrivateKeyEntry)keyStore.getEntry(alias, null);
RSAPublicKey publicKey = (RSAPublicKey) privateKeyEntry.getCertificate().getPublicKey();
String initialText = startText.getText().toString();
if(initialText.isEmpty())
Toast.makeText(this, "Enter text in the 'Initial Text' widget", Toast.LENGTH_LONG).show();
return;
Cipher inCipher = Cipher.getInstance("RSA/ECB/PKCS1Padding", "AndroidOpenSSL");
inCipher.init(Cipher.ENCRYPT_MODE, publicKey);
ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
CipherOutputStream cipherOutputStream = new CipherOutputStream(
outputStream, inCipher);
cipherOutputStream.write(initialText.getBytes("UTF-8"));
cipherOutputStream.close();
byte [] vals = outputStream.toByteArray();
encryptedText.setText(Base64.encodeToString(vals, Base64.DEFAULT));
catch (Exception e)
Toast.makeText(this, "Exception " + e.getMessage() + " occurred", Toast.LENGTH_LONG).show();
Log.e(TAG, Log.getStackTraceString(e));
[![在此处输入图片描述][2]][2]
新更新：
加密代码
public void encryptString(String alias)
try
KeyStore keyStore = KeyStore.getInstance("AndroidKeyStore");
keyStore.load(null);
SecretKey secretKey = (SecretKey) keyStore.getKey(alias, null);
String initialText = startText.getText().toString();
if(initialText.isEmpty())
Toast.makeText(this, "Enter text in the 'Initial Text'", Toast.LENGTH_LONG).show();
return;
Cipher inCipher = Cipher.getInstance("AES/GCM/NoPadding");
inCipher.init(Cipher.ENCRYPT_MODE, secretKey);
byte[] src= initialText.getBytes("UTF-8");
byte[] iv = inCipher.getIV();
assert iv.length == 12;
byte[] cipherText = inCipher.doFinal(src);
assert cipherText.length == src.length + 16;
byte[] message = new byte[12 + src.length + 16];
System.arraycopy(iv, 0, message, 0, 12);
System.arraycopy(cipherText, 0, message, 12, cipherText.length);
//ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
//CipherOutputStream cipherOutputStream = new CipherOutputStream(
// outputStream, inCipher);
//cipherOutputStream.write(message);
//cipherOutputStream.close();
//byte [] vals = outputStream.toByteArray();
encryptedText.setText(Base64.encodeToString(message, Base64.DEFAULT));
catch (Exception e)
Toast.makeText(this, "Exception " + e.getMessage() + " occurred", Toast.LENGTH_LONG).show();
Log.e(TAG, Log.getStackTraceString(e));
解密代码：（不工作）
public void decryptString(String alias)
try
KeyStore keyStore = KeyStore.getInstance("AndroidKeyStore");
keyStore.load(null);
SecretKey secretKey = (SecretKey) keyStore.getKey(alias, null);
String cipherText = encryptedText.getText().toString();
byte[] src = cipherText.getBytes();
byte[] message = new byte[12 + src.length + 16];
Cipher output = Cipher.getInstance("AES/GCM/NoPadding");
GCMParameterSpec params = new GCMParameterSpec(128, message, 0, 12);
output.init(Cipher.DECRYPT_MODE, secretKey, params);
// output.doFinal(message, 12, message.length - 12);
CipherInputStream cipherInputStream = new CipherInputStream(
new ByteArrayInputStream(Base64.decode(cipherText, Base64.DEFAULT)), output);
ArrayList<Byte> values = new ArrayList<>();
int nextByte;
while ((nextByte = cipherInputStream.read()) != -1)
values.add((byte)nextByte);
byte[] bytes = new byte[values.size()];
for(int i = 0; i < bytes.length; i++)
bytes[i] = values.get(i).byteValue();
String finalText = new String(bytes, 0, bytes.length, "UTF-8");
decryptedText.setText(finalText);
catch (Exception e)
Toast.makeText(this, "Exception " + e.getMessage() + " occurred", Toast.LENGTH_LONG).show();
Log.e(TAG, Log.getStackTraceString(e));
您能帮我解决图片中显示的错误吗？
[![在此处输入图片描述][3]][3]
加密函数：
public void encryptString(String alias)
try
KeyStore keyStore = KeyStore.getInstance("AndroidKeyStore");
keyStore.load(null);
SecretKey secretKey = (SecretKey) keyStore.getKey(alias, null);
String initialText = startText.getText().toString();
if(initialText.isEmpty())
Toast.makeText(this, "Enter text in the 'Initial Text'", Toast.LENGTH_LONG).show();
return;
Cipher inCipher = Cipher.getInstance("AES/GCM/NoPadding");
inCipher.init(Cipher.ENCRYPT_MODE, secretKey);
byte[] src= initialText.getBytes("UTF-8");
byte[] iv = inCipher.getIV();
assert iv.length == 12;
byte[] cipherText = inCipher.doFinal(src);
assert cipherText.length == src.length + 16;
byte[] message = new byte[12 + src.length + 16];
System.arraycopy(iv, 0, message, 0, 12);
System.arraycopy(cipherText, 0, message, 12, cipherText.length);
encryptedText.setText(Base64.encodeToString(message, Base64.DEFAULT));
catch (Exception e)
Toast.makeText(this, "Exception " + e.getMessage() + " occurred", Toast.LENGTH_LONG).show();
Log.e(TAG, Log.getStackTraceString(e));
解密函数：
public void decryptString(String alias)
try
KeyStore keyStore = KeyStore.getInstance("AndroidKeyStore");
keyStore.load(null);
SecretKey secretKey = (SecretKey) keyStore.getKey(alias, null);
String cipherText = encryptedText.getText().toString();
Cipher cipher = Cipher.getInstance("AES/GCM/NoPadding");
byte[] nonceCiphertextTag = Base64.decode(cipherText, Base64.DEFAULT);
GCMParameterSpec params = new GCMParameterSpec(128, nonceCiphertextTag, 0, 12);
cipher.init(Cipher.DECRYPT_MODE, secretKey, params);
byte[] decrypted = cipher.doFinal(nonceCiphertextTag, 12, nonceCiphertextTag.length - 12);
String finalText = new String(decrypted, 0, decrypted.length, "UTF-8");
decryptedText.setText(finalText);
catch (Exception e)
Toast.makeText(this, "Exception " + e.getMessage() + " occurred", Toast.LENGTH_LONG).show();
Log.e(TAG, Log.getStackTraceString(e));
非常感谢@Topaco 的帮助
【问题讨论】：
encryptedText.getText() 似乎只是一个字符串，其中包含两个用分号分隔的 Base64 编码部分。为什么不能将它们分开，例如split()?然后你就可以对这两个部分进行Base64解码并处理/应用它们。
关于使用IV进行解密请看here。您实际上创建了一个 GCMParameterSpec()，它封装了 IV，并作为第三个参数传递给 cipher.init()。
顺便说一下，链接的示例还显示了更有效的连接，即在字节级别。这里不需要分隔符，因为分隔符是基于已知长度的（例如，GCM 上下文中的 IV/nonce 为 12 个字节）。
【参考方案1】：
在最新发布的加密代码中，将nonce、密文和标签串联起来并进行Base64编码，以下称为nonceCiphertextTagB64。
解密时
nonceCiphertextTagB64必须先Base64解码为nonceCiphertextTag，
nonce 必须封装在GCMParameterSpec 实例中； nonce 是 nonceCiphertextTag 的前 12 个字节，
必须创建AES/GCM/NoPadding 的密码实例，使用密钥和解密模式下的GCMParameterSpec 实例进行初始化，
密文和标签的拼接被解密；密文和标签的拼接就是nonce之后的数据。
在以下示例实现中，对于 repro，使用 32 字节密钥 01234567890123456789012345678901（而不是密钥库中的密钥）。密文是使用发布的密码创建的，使用相同的密钥和明文进行加密快速棕色狐狸跳过懒狗：
...
String nonceCiphertextTagB64 =
"UpyxMnzPrw+zJGANL4wBbaC+UX5KnMKYwhR0u2iF/GDCcU38YKWlvJp1zJ+mrN0POP7lz9y+eweH\n" +
"vIxAH4R4U3At8T0fVe0=";
SecretKeySpec secretKey = new SecretKeySpec("01234567890123456789012345678901".getBytes(StandardCharsets.UTF_8),"AES");
byte[] nonceCiphertextTag = Base64.decode(nonceCiphertextTagB64, Base64.DEFAULT);
GCMParameterSpec params = new GCMParameterSpec(128, nonceCiphertextTag, 0, 12);
Cipher cipher = Cipher.getInstance("AES/GCM/NoPadding");
cipher.init(Cipher.DECRYPT_MODE, secretKey, params);
byte[] decrypted = cipher.doFinal(nonceCiphertextTag, 12, nonceCiphertextTag.length - 12);
System.out.println(new String(decrypted, StandardCharsets.UTF_8)); // The quick brown fox jumps over the lazy dog
...
输出是：
The quick brown fox jumps over the lazy dog
【讨论】：
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