函數描述 : 文本數據進行DES解密
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+(NSString *) decryptUseDES:(NSData *)plainText key:(NSString *)key
{
NSString *cleartext = nil;
// NSData *textData = [self parseHexToByteArray:plainText];
NSData *textData = plainText;
NSUInteger dataLength = [textData length];
size_t bufferSize = dataLength + kCCBlockSizeAES128;
void *buffer = malloc(bufferSize);
size_t numBytesEncrypted = 0;
CCCryptorStatus cryptStatus = CCCrypt(kCCDecrypt, kCCAlgorithmDES,
kCCOptionPKCS7Padding | kCCOptionECBMode,
[key UTF8String], kCCKeySizeDES,
NULL,
[textData bytes] , dataLength,
buffer, bufferSize,
&numBytesEncrypted);
if (cryptStatus == kCCSuccess) {
NSLog(@"DES解密成功");
NSData *data = [NSData dataWithBytes:buffer length:(NSUInteger)numBytesEncrypted];
cleartext = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
}else{
NSLog(@"DES解密失敗");
}
free(buffer);
return cleartext;
}