问题描述
这是我的java代码。现在我想在Objective-C中实现相同的功能。 加密加密密码;
IvParameterSpec iv = new IvParameterSpec（key）;
SecretKeySpec skeySpec = new SecretKeySpec（key，AES）;
encryptCipher = Cipher.getInstance（AES / CBC / PKCS5Padding）;
encryptCipher.init（Cipher.ENCRYPT_MODE，skeySpec，iv）;
byte [] encrypted = encryptCipher.doFinal（dataToEncrypt.getBytes（））;
Log.d（TAG，encrypted string：
+ Base64.encodeToString（encrypted，Base64.DEFAULT））;
返回Base64.encodeToString（加密，Base64.DEFAULT）.trim（）;
这是我的iOS实现
- （NSData *）AES256EncryptWithKey :( NSString *）键
{
char keyPtr [kCCKeySizeAES256 + 1];
bzero（keyPtr，sizeof（keyPtr））;
[key getCString：keyPtr maxLength：sizeof（keyPtr）encoding：NSUTF8StringEncoding];
NSUInteger dataLength = [self length];
size_t bufferSize = dataLength + kCCBlockSizeAES128;
void * buffer = malloc（bufferSize）;
size_t numBytesEncrypted = 0;
CCCryptorStatus cryptStatus = CCCrypt（kCCEncrypt，
kCCAlgorithmAES128，
kCCOptionPKCS7Padding，
keyPtr，
kCCKeySizeAES256，
NULL，
[self bytes]
dataLength，
buffer，
bufferSize，
& numBytesEncrypted）;
if（cryptStatus == kCCSuccess）
{
return [NSData dataWithBytesNoCopy：buffer length：numBytesEncrypted];
}
free（buffer）;
return nil;
}
这是我的哈希键生成功能。这个函数在android和ios中返回相同的键
int dkLen = 16;
NSData * keyData = [hash_key dataUsingEncoding：NSUTF8StringEncoding];
NSData * salt = [saltKey dataUsingEncoding：NSUTF8StringEncoding];
uint rounds = 1000;
uint keySize = kCCKeySizeAES128;
NSMutableData * derivedKey = [NSMutableData dataWithLength：keySize];
CCKeyDerivationPBKDF（kCCPBKDF2，// algorithm
keyData.bytes，// password
keyData.length， // passwordLength
salt.bytes，// salt
salt.length，// saltLen
kCCPRFHmacAlgSHA1，// PRF
rounds，// rounds
derivKey.mutableBytes ，// derivedKey
dkLen * 8）;
return derivedKey;
我得到不同的输出。我做错了什么？答案是帮助我找出来。
一个问题是Java代码使用CBC模式， iOS代码使用ECB模式。
接下来，从引用的项目：
// result = yHbhApwTpQ2ZhE97AKF / g = =
无效的Base64，它不包含4个字节的倍数。
使用以下选项：CBC，PKCS＃7填充
输入：
数据：hello，它将被填充到16字节的块长度
键：
base64：VQQhu + dUdqXGoE7RZL2JWg ==
hex：550421bbe75476a5c6a04ed164bd895a
iv：
base64：VQQhu + dUdqXGoE7RZL2JWg ==
hex：550421bbe75476a5c6a04ed164bd895a
加密输出：
hex：ff21db840a704e943666113dec0285fe
base64：/ yHbhApwTpQ2ZhE97AKF / g ==
这是测试代码：
NSString * base64Key = @VQQhu + dUdqXGoE7RZL2JWg ==;
NSString * dataString = @hello;
NSData * key = [[NSData alloc] initWithBase64EncodedString：base64Key options：0];
NSData * data = [dataString dataUsingEncoding：NSUTF8StringEncoding];
NSLog（@key：％@，key）;
NSLog（@data：％@，data）;
NSData * encryptedData = [TestClass crypt：data
iv：key
key：key
上下文：kCCEncrypt];
NSLog（@encryptedData：％@，encryptedData）;
NSString * encryptedBase64Data = [encryptedData base64EncodedStringWithOptions：0];
NSLog（@encryptedBase64Data：％@，encryptedBase64Data）;
这是加密方法（在类 TestClass iv :(（NSData *））$（$）$（$）$ iv
key：（NSData *）symmetricKey
上下文：（CCOperation）encryptOrDecrypt
{
CCCryptorStatus ccStatus = kCCSuccess;
size_t cryptBytes = 0; //移动到缓冲区的字节数。
NSMutableData * dataOut = [NSMutableData dataWithLength：dataIn.length + kCCBlockSizeAES128];
ccStatus = CCCrypt（encryptOrDecrypt，
kCCAlgorithmAES128，
kCCOptionPKCS7Padding，
symmetricKey.bytes，
kCCKeySizeAES128，
iv.bytes，
dataIn.bytes，
dataIn.length，
dataOut.mutableBytes，
dataOut.length，
& cryptBytes）;
if（ccStatus！= kCCSuccess）{
NSLog（@CCCrypt status：％d，ccStatus）;
}
dataOut.length = cryptBytes;
return dataOut;
}
注意：我不断分开加密和数据转换。如果您使用在线加密实现，则填充将可能不是PKCS＃7，因为mcrypt不支持它，而是它做非标准的空填充。由于pad字节只是pad字节的计数，所以可以在输入中模拟填充。以下是使用
请注意，填充为16个字节的块大小的helloPKCS＃7添加了11个字节的uint8值11或 0x0B ： 68656c6c6f0B0B0B0B0B0B0B0B0B0B0B 。
最后问题仍然是为什么Java代码不会产生这个结果？
This is my java code. Now I want to implement same functionality in Objective-C.
Cipher encryptCipher;
IvParameterSpec iv = new IvParameterSpec(key);
SecretKeySpec skeySpec = new SecretKeySpec(key, "AES");
encryptCipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
encryptCipher.init(Cipher.ENCRYPT_MODE, skeySpec, iv);
byte[] encrypted = encryptCipher.doFinal(dataToEncrypt.getBytes());
Log.d("TAG", "encrypted string:"
+ Base64.encodeToString(encrypted, Base64.DEFAULT));
return Base64.encodeToString(encrypted, Base64.DEFAULT).trim();
This is my iOS implementation
- (NSData *)AES256EncryptWithKey:(NSString*)key
{
char keyPtr[kCCKeySizeAES256 + 1];
bzero(keyPtr, sizeof(keyPtr));
[key getCString:keyPtr maxLength:sizeof(keyPtr) encoding:NSUTF8StringEncoding];
NSUInteger dataLength = [self length];
size_t bufferSize = dataLength + kCCBlockSizeAES128;
void* buffer = malloc(bufferSize);
size_t numBytesEncrypted = 0;
CCCryptorStatus cryptStatus = CCCrypt(kCCEncrypt,
kCCAlgorithmAES128,
kCCOptionPKCS7Padding,
keyPtr,
kCCKeySizeAES256,
NULL,
[self bytes],
dataLength,
buffer,
bufferSize,
&numBytesEncrypted);
if (cryptStatus == kCCSuccess)
{
return [NSData dataWithBytesNoCopy:buffer length:numBytesEncrypted];
}
free(buffer);
return nil;
}
This is my hash key generating function. this function return same key in android and ios
int dkLen = 16;
NSData *keyData = [hash_key dataUsingEncoding:NSUTF8StringEncoding];
NSData *salt = [saltKey dataUsingEncoding:NSUTF8StringEncoding];
uint rounds = 1000;
uint keySize = kCCKeySizeAES128;
NSMutableData *derivedKey = [NSMutableData dataWithLength:keySize];
CCKeyDerivationPBKDF(kCCPBKDF2, // algorithm
keyData.bytes, // password
keyData.length, // passwordLength
salt.bytes, // salt
salt.length, // saltLen
kCCPRFHmacAlgSHA1, // PRF
rounds, // rounds
derivedKey.mutableBytes, // derivedKey
dkLen*8);
return derivedKey;
I am getting a different output. I am doing anything wrong?.please help me to find out.
One problem is that the Java code used CBC mode, the iOS code used ECB mode.
Next, from the referenced project://result= yHbhApwTpQ2ZhE97AKF/g==
is invalid Base64, it does not contain a multiple of 4 bytes.
With these options: CBC, PKCS#7 padding
inputs:
data in: "hello" which will be null padded to the block length of 16-bytes
key:
base64: VQQhu+dUdqXGoE7RZL2JWg==
hex: 550421bbe75476a5c6a04ed164bd895a
iv:
base64: VQQhu+dUdqXGoE7RZL2JWg==
hex: 550421bbe75476a5c6a04ed164bd895a
encrypted output:
hex: ff21db840a704e943666113dec0285fe
base64: /yHbhApwTpQ2ZhE97AKF/g==
This is the test code:
NSString *base64Key = @"VQQhu+dUdqXGoE7RZL2JWg==";
NSString *dataString = @"hello";
NSData *key = [[NSData alloc] initWithBase64EncodedString:base64Key options:0];
NSData *data = [dataString dataUsingEncoding:NSUTF8StringEncoding];
NSLog(@"key: %@", key);
NSLog(@"data: %@", data);
NSData *encryptedData = [TestClass crypt:data
iv:key
key:key
context:kCCEncrypt];
NSLog(@"encryptedData: %@", encryptedData);
NSString *encryptedBase64Data = [encryptedData base64EncodedStringWithOptions:0];
NSLog(@"encryptedBase64Data: %@", encryptedBase64Data);
This is the encryption method (in the class TestClass):
+ (NSData *)crypt:(NSData *)dataIn
iv:(NSData *)iv
key:(NSData *)symmetricKey
context:(CCOperation)encryptOrDecrypt
{
CCCryptorStatus ccStatus = kCCSuccess;
size_t cryptBytes = 0; // Number of bytes moved to buffer.
NSMutableData *dataOut = [NSMutableData dataWithLength:dataIn.length + kCCBlockSizeAES128];
ccStatus = CCCrypt( encryptOrDecrypt,
kCCAlgorithmAES128,
kCCOptionPKCS7Padding,
symmetricKey.bytes,
kCCKeySizeAES128,
iv.bytes,
dataIn.bytes,
dataIn.length,
dataOut.mutableBytes,
dataOut.length,
&cryptBytes);
if (ccStatus != kCCSuccess) {
NSLog(@"CCCrypt status: %d", ccStatus);
}
dataOut.length = cryptBytes;
return dataOut;
}
Note: I keep separate the encryption and data conversions. Conflating them just makes testing more complicated.
If you use an on-line encryption implementation the padding will probably not be PKCS#7 because mcrypt does not support it, instead it does non-standard null padding. Since the pad bytes are just the count of pad bytes the padding can be simulated in the input. Here is an example using AES – Symmetric Ciphers Online
Note that "hello" PKCS#7 padded to a block size of 16 bytes adds 11 bytes of the uint8 value 11 or 0x0B: 68656c6c6f0B0B0B0B0B0B0B0B0B0B0B.
Finally the question remains why the Java code does not produce this result?
这篇关于在IOS中实现AES256加密的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！