Well, I'm trying to encrypt a string in an object c, extending NSData with this method:
@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 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
then I call it here:
NSString *strData = @"My string";
NSData *objNSData = [NSData dataWithData:[strData dataUsingEncoding: NSUTF8StringEncoding]];
NSLog(@"encrypted: %@",[objNSData description]);
If I just use it in the c lens, it works fine. But when I try to send it to the java server, it does not work.
My encryption data looks like this:
86fcf0fa9e3dff93dc8918ffd02ee203 12de0bf8c8ba300456293c4240296c0d
and if I try to encrypt it in java using also AES with the same key, I get the following:
86fcf0fa9e3dff93dc8918ffd02ee203 8388f173da143c6aeeb90e554259c83c
its strange because the first half of it is the same.
Does anyone know why this might happen? thank.