问用OpenSSL和CommonCrypto加密

EN

openssl enc -aes256 -a -e -nosalt -in InputFileWithString.txt -out OutputFile.txt thisisthekey

+(NSString *)encryptText:(NSString *)text withKey:(NSString *)key{
    NSData *plainData = [text dataUsingEncoding:NSUTF8StringEncoding];

    NSData *encryptedData = [plainData AES256EncryptWithKey:key];

    NSString *base64String = [encryptedData base64EncodedStringWithOptions:0];

    return base64String;
}

- (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;
}