我有一个函数要求我将加密的 JSON 实例发送到 PHP 服务器进行验证。我在尝试启动并运行整个过程并弄乱我的脑袋以找出问题所在时遇到了问题。
-(void) sendData:(NSString*)theweb{
//preparing sample json
NSMutableDictionary * dict = [[NSMutableDictionary alloc]init];
[dict setObject:@"test" forKey:@"example"];
[dict setObject:@"1" forKey:@"p"];
[dict setObject:@"yourPostMessage" forKey:@"test"];
[dict setObject:@"isNotReal" forKey:@"this"];
//json creation
NSData* data2 = [JSONBuilder toJSON:dict];
NSString * jsonstring = [[NSString alloc]initWithData:data2 encoding:NSUTF8StringEncoding];
//creating a dummy sha256 hash for aes256 key.
NSString * string3 = [self sha256HashFor:@"hello"];
//trimming hash to 32 character key.
string3 = [string3 substringToIndex:32];
//encrypting data to aes256
data2 = [data2 AES256EncryptWithKey:string3];
NSString * b64= [data2 base64EncodedString];
NSString *post = [NSString stringWithFormat:@"theRealData=%@",b64];
NSData *postData = [post dataUsingEncoding:NSUTF8StringEncoding allowLossyConversion:NO];
requestObj = nil;
//NSMutableRequest
requestObj = [NSMutableURLRequest requestWithURL:[NSURL URLWithString:theweb]];
NSString *postLength = [NSString stringWithFormat:@"%d", [postData length]];
[requestObj setValue:@"application/x-www-form-urlencoded;charset=charset=us-ascii" forHTTPHeaderField:@"Content-Type"];
[requestObj setValue:postLength forHTTPHeaderField:@"Content-Length"];
[requestObj setHTTPMethod:@"POST"];
[requestObj setHTTPBody:postData];
//calling a new NSURLConnection
conn = nil;
conn = [NSURLConnection connectionWithRequest:requestObj delegate:self];
[conn start];
}
该函数中使用的方法如下：
+(NSData*)toJSON :(NSMutableDictionary*)dictionary
{
NSError* error = nil;
id result = [NSJSONSerialization dataWithJSONObject:dictionary options:kNilOptions error:&error];
if (error != nil) return nil;
return result;
}
-(NSString*)sha256HashFor:(NSString*)input
{
const char* str = [input UTF8String];
unsigned char result[CC_SHA256_DIGEST_LENGTH];
CC_SHA256(str, strlen(str), result);
NSMutableString *ret = [NSMutableString stringWithCapacity:CC_SHA256_DIGEST_LENGTH*2];
for(int i = 0; i<CC_SHA256_DIGEST_LENGTH; i++)
{
[ret appendFormat:@"%02x",result[i]];
}
return ret;
}
- (NSData *)AES256EncryptWithKey:(NSString *)key {
// 'key' should be 32 bytes for AES256, will be null-padded otherwise
char keyPtr[kCCKeySizeAES256+1]; // room for terminator (unused)
bzero(keyPtr, sizeof(keyPtr)); // fill with zeroes (for padding)
// fetch key data
[key getCString:keyPtr maxLength:sizeof(keyPtr) encoding:NSUTF8StringEncoding];
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 numBytesEncrypted = 0;
CCCryptorStatus cryptStatus = CCCrypt(kCCEncrypt, kCCAlgorithmAES128, kCCOptionPKCS7Padding,
keyPtr, kCCKeySizeAES256,
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;
}
这是php上的代码：
function decrypt_data($data, $key) {
//$padded_key = $key . str_repeat(chr(0x00), 16); // Argh!
//var_dump($padded_key);
var_dump(base64_decode($data,true));
$result = mcrypt_decrypt(MCRYPT_RIJNDAEL_128, $key, base64_decode($data), 'ecb');
var_dump($result);
// Yetch - $result ends up being padded with 0x0b's (vertical tab).
$result2 = rtrim($result, chr(0x0b));
return $result2;
}
以下是我的发现：
Output of Base64 string(Gotten on both sides):
UalnWmRiMQv8z4mEm+6B3HFSbiDwWcK1LYPhk6jDq+DiwYzvxqoZuDnlJUAjWbX6sQepiL8fb8/JQ0NXhQocglIcJN759AbpVSsbiXmwL78=
Output of vardump on base64_decode on PHP side:
BOOL(false)
Output of vardump on $result: none
不知何故，我觉得问题出在编码上。有人可以指导我吗？我很茫然。