关于java：在Android和IPhone中使用AES-128进行加密（结果不同）

Encryption using AES-128 in Android and IPhone (Different result)

我尝试在Android和iPhone平台上使用AES算法加密一些文本。我的问题是，即使使用相同的加密/解密算法(aes-128)和相同的固定变量(key、iv、mode)，在两个平台上也会得到不同的结果。我包含了两个平台的代码示例，用于测试加密/解密。如果能帮我判断我做错了什么，我将不胜感激。

密钥："123456789abcdefg"
四："1111111111111111"
纯文本："hellothere"
模式："aes/cbc/nopadding"

Android代码：

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public class Crypto {
private final static String HEX ="0123456789ABCDEF";

public static String encrypt(String seed, String cleartext)
throws Exception {
byte[] rawKey = getRawKey(seed.getBytes());
byte[] result = encrypt(rawKey, cleartext.getBytes());
return toHex(result);
}

public static String decrypt(String seed, String encrypted)
throws Exception {
byte[] rawKey = getRawKey(seed.getBytes());
byte[] enc = toByte(encrypted);
byte[] result = decrypt(rawKey, enc);
return new String(result);
}

private static byte[] getRawKey(byte[] seed) throws Exception {
KeyGenerator kgen = KeyGenerator.getInstance("CBC");
SecureRandom sr = SecureRandom.getInstance("SHA1PRNG");
sr.setSeed(seed);
kgen.init(128, sr); // 192 and 256 bits may not be available
SecretKey skey = kgen.generateKey();
byte[] raw = skey.getEncoded();
return raw;
}

private static byte[] encrypt(byte[] raw, byte[] clear) throws Exception {
SecretKeySpec skeySpec = new SecretKeySpec(raw,"AES");
Cipher cipher = Cipher.getInstance("AES");
cipher.init(Cipher.ENCRYPT_MODE, skeySpec);
byte[] encrypted = cipher.doFinal(clear);
return encrypted;
}

private static byte[] decrypt(byte[] raw, byte[] encrypted)
throws Exception {
SecretKeySpec skeySpec = new SecretKeySpec(raw,"AES");
Cipher cipher = Cipher.getInstance("AES");
cipher.init(Cipher.DECRYPT_MODE, skeySpec);
byte[] decrypted = cipher.doFinal(encrypted);
return decrypted;
}

public static String toHex(String txt) {
return toHex(txt.getBytes());
}

public static String fromHex(String hex) {
return new String(toByte(hex));
}

public static byte[] toByte(String hexString) {
int len = hexString.length() / 2;
byte[] result = new byte[len];
for (int i = 0; i < len; i++)
result[i] = Integer.valueOf(hexString.substring(2 * i, 2 * i + 2),
16).byteValue();
return result;
}

public static String toHex(byte[] buf) {
if (buf == null)
return"";

StringBuffer result = new StringBuffer(2 * buf.length);
for (int i = 0; i < buf.length; i++) {
appendHex(result, buf[i]);
}

return result.toString();
}

private static void appendHex(StringBuffer sb, byte b) {
sb.append(HEX.charAt((b >> 4) & 0x0f)).append(HEX.charAt(b & 0x0f));
}
}

iPhone(Objective-C)代码：

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- (NSData *) transform:(CCOperation) encryptOrDecrypt data:(NSData *) inputData {

NSData* secretKey = [Cipher md5:cipherKey];

CCCryptorRef cryptor = NULL;
CCCryptorStatus status = kCCSuccess;

uint8_t iv[kCCBlockSizeAES128];
memset((void *) iv, 0x0, (size_t) sizeof(iv));

status = CCCryptorCreate(encryptOrDecrypt, kCCAlgorithmAES128, kCCOptionPKCS7Padding,
[secretKey bytes], kCCKeySizeAES128, iv, &cryptor);

if (status != kCCSuccess) {
return nil;
}

size_t bufsize = CCCryptorGetOutputLength(cryptor, (size_t)[inputData length], true);

void * buf = malloc(bufsize * sizeof(uint8_t));
memset(buf, 0x0, bufsize);

size_t bufused = 0;
size_t bytesTotal = 0;

status = CCCryptorUpdate(cryptor, [inputData bytes], (size_t)[inputData length],
buf, bufsize, &bufused);

if (status != kCCSuccess) {
free(buf);
CCCryptorRelease(cryptor);
return nil;
}

bytesTotal += bufused;

status = CCCryptorFinal(cryptor, buf + bufused, bufsize - bufused, &bufused);

if (status != kCCSuccess) {
free(buf);
CCCryptorRelease(cryptor);
return nil;
}

bytesTotal += bufused;

CCCryptorRelease(cryptor);

return [NSData dataWithBytesNoCopy:buf length:bytesTotal];
}

+ (NSData *) md5:(NSString *) stringToHash {

const char *src = [stringToHash UTF8String];

unsigned char result[CC_MD5_DIGEST_LENGTH];

CC_MD5(src, strlen(src), result);

return [NSData dataWithBytes:result length:CC_MD5_DIGEST_LENGTH];
}

号

我的一些参考资料：

http://code.google.com/p/aes-encryption-samples/wiki/howtoEncryptWithJava
http://automagical.rationalmind.net/2009/02/12/aes-interoperability-between-net-and-iphone/
.NET和iPhone之间的AES互操作性？