使用AES-128加密/解密字節數組> 256字節

Question

以下代碼使用AES-128將字節數組SOURCE_DATA加密到另一個字節數組ENCRYPTED_DATA，然後再次將其解密爲DECRYPTED_DATA。對於< = 256字節的字節數組，代碼工作得很好，但如果字節數組更長，則DECRYPTED_DATA只在字節256後面包含零，並且不等於SOURCE_DATA數組。我錯過了什麼？

輸出：

源數據：... fbfcfdfeff0001
解密的數據：... fbfcfdfeff000

代碼：

// Create data array with size greater 256 bytes 
byte[] SOURCE_DATA = new byte[257];  
for (int i=0;i<SOURCE_DATA.length; i++) { 
    SOURCE_DATA[i] = (byte)((i+1) & 0xff); 
} 

// Init ciphers 
Cipher encC = Cipher.getInstance("AES/ECB/PKCS5Padding"); 
Cipher decC = Cipher.getInstance("AES/ECB/PKCS5Padding"); 
encC.init(Cipher.ENCRYPT_MODE, new SecretKeySpec(new byte[] {0,1,2,3,4,5,6,7,8,9,1,2,3,4,5,6}, "AES"));     
decC.init(Cipher.DECRYPT_MODE, new SecretKeySpec(new byte[] {0,1,2,3,4,5,6,7,8,9,1,2,3,4,5,6}, "AES"));   

// Encrypt 
ByteArrayOutputStream bos = new ByteArrayOutputStream(); 
CipherOutputStream cos = new CipherOutputStream(bos, encC); 
DataOutputStream dos = new DataOutputStream(cos); 

dos.write(SOURCE_DATA, 0, SOURCE_DATA.length); 
dos.close(); 

byte[] ENCRYPTED_DATA = bos.toByteArray(); 

// Decrypt 
ByteArrayInputStream bis = new ByteArrayInputStream(ENCRYPTED_DATA); 
CipherInputStream cis = new CipherInputStream(bis, decC); 
DataInputStream dis = new DataInputStream(cis); 

byte[] DECRYPTED_DATA = new byte[SOURCE_DATA.length]; 
dis.read(DECRYPTED_DATA, 0, DECRYPTED_DATA.length); 
cis.close(); 

System.out.println("Source Data: "+toHex(SOURCE_DATA)); 
System.out.println("Decrypted Data: "+toHex(DECRYPTED_DATA));    

Answer 1

TR y使用DataInputStream.readFully（即你只是讀取結果的一部分，這就是爲什麼你總是在一個while循環中調用InputStream.read）。