Objective-c AES加密看起来不像java AES加密

Question

我试图用这种方法加密目标c中扩展NSData的字符串:

 @implementation NSData (AES128)



(NSData *)AES128Encrypt {
char keyPtr[kCCKeySizeAES128] = {'\xe1','\xaa','\x9c','\x61','\x46','\x74','\x44','\x56','\xf0','\xe5','\x47','\x46','\x86','\xdc','\x95','\x77'};

NSUInteger dataLength = [self length];

size_t bufferSize = dataLength + kCCBlockSizeAES128;
void *buffer = malloc(bufferSize);

size_t numBytesEncrypted = 0;
CCCryptorStatus cryptStatus = CCCrypt(kCCEncrypt,kCCAlgorithmAES128,kCCOptionPKCS7Padding,keyPtr,kCCKeySizeAES128,NULL /* initialization vector (optional) /,[self bytes], dataLength, / input /buffer, bufferSize, / output */
        &numBytesEncrypted);
if (cryptStatus == kCCSuccess) {
//the returned NSData takes ownership of the buffer and will free it on deallocation
return [NSData dataWithBytesNoCopy:buffer length:numBytesEncrypted];
}

free(buffer); //free the buffer;
return nil;
}
(NSData *)AES128Decrypt {
char keyPtr[kCCKeySizeAES128] = {'\xe1','\xaa','\x9c','\x61','\x46','\x74','\x44','\x56','\xf0','\xe5','\x47','\x46','\x86','\xdc','\x95','\x77'};

NSUInteger dataLength = [self length];

//See the doc: For block ciphers, the output size will always be less than or 
//equal to the input size plus the size of one block.
//That's why we need to add the size of one block here
size_t bufferSize = dataLength + kCCBlockSizeAES128;
void *buffer = malloc(bufferSize);

size_t numBytesDecrypted = 0;
CCCryptorStatus cryptStatus=CCCrypt(kCCDecrypt,kCCAlgorithmAES128,kCCOptionPKCS7Padding,keyPtr, kCCKeySizeAES128,NULL /* initialization vector (optional) /,[self bytes], dataLength, / input /buffer, bufferSize, / output */&numBytesDecrypted);

if (cryptStatus == kCCSuccess) {
//the returned NSData takes ownership of the buffer and will free it on deallocation
return [NSData dataWithBytesNoCopy:buffer length:numBytesDecrypted];
}

free(buffer); //free the buffer;
return nil;
}


@end
 

然后我在这里称呼它:

NSString *strData = @"My string";


NSData *objNSData = [NSData dataWithData:[strData dataUsingEncoding: NSUTF8StringEncoding]];

NSLog(@"encrypted: %@",[objNSData description]);
 

如果我只是在目标c中使用它,它工作正常.但是当我尝试将它发送到java服务器时,它不起作用.

我的密码数据看起来像这样:

86fcf0fa9e3dff93dc8918ffd02ee203 12de0bf8c8ba300456293c4240296c0d

如果我尝试使用相同的密钥使用AES密码在java中,我得到这个:

86fcf0fa9e3dff93dc8918ffd02ee203 8388f173da143c6aeeb90e554259c83c

它很奇怪,因为它的上半部分是一样的.

有人知道为什么会这样吗？谢谢.

Answer 1

我从来没有做过任何Objective-C编程,但我几乎肯定你在代码中使用不同模式的 AES .您需要确保这些是一致的.默认值可能是密码块链接(CBC)模式.确保在Java代码中设置此选项.

顺便说一句,CBC模式应该有一个随机的初始化向量(IV)而不是NULL(我假设使用全零).这也需要在两者之间保持一致.

我不得不给出加密的标准免责声明,使用更高级别的协议来处理这些东西通常会更安全,例如传输中的数据的SSL/TLS以及类似于Keyczar的数据.使密码正确是非常困难的,一个小错误(如选择一个错误的模式)可以完全破坏系统的安全性.