Students who frequently download videos and games often encounter Xunlei download links starting with ’thunder://’, but are often unable to download due to copyright issues. Here, we will explain the conversion between regular download URLs and Xunlei download links.

For example, a random download link is: https://www.bobobk.com/favicon.ico

1. Converting a Regular URL to a Xunlei Link

1.1 Add “AA” to the beginning and “ZZ” to the end of the original URL. The address becomes: AAhttps://www.bobobk.com/favicon.icoZZ

1.2 Base64 encode this address:

QUFodHRwczovL3d3dy5ib2JvYmsuY29tL2Zhdmljb24uaWNvWlo=

1.3 The Xunlei dedicated link is created by adding thunder:// before the above address:

thunder://QUFodHRwczovL3d3dy5ib2JvYmsuY29tL2Zhdmljb24uaWNvWlo=

Conversion Code

import base64
    def convert_to_thunder(s):
        s1  = "AA"+s+"ZZ"
        s2 = base64.b64encode(s1.encode())
        s3 = "thunder://" + s2.decode()
        return s3
normal_url  = 'https://www.bobobk.com/favicon.ico'
print(convert_to_thunder(normal_url))

2. Converting a Xunlei Link to a Regular URL

2.1 Remove “thunder://” from the beginning of the original link.

The address becomes: QUFodHRwczovL3d3dy5ib2JvYmsuY29tL2Zhdmljb24uaWNvWlo=

2.2 Base64 decode this address:

AAhttps://www.bobobk.com/favicon.icoZZ

2.3 Remove “AA” from the front and “ZZ” from the back.

https://www.bobobk.com/favicon.ico

Conversion Code

import base64
    def convert_thunder(s):
        s1  = s.strip().split("//")[1]
        s2 = base64.b64decode(s1).decode()
        s3 = s2[2:-2]
        return s3
thunder = 'thunder://QUFodHRwczovL3d3dy5ib2JvYmsuY29tL2Zhdmljb24uaWNvWlo='
print(convert_thunder(thunder))

JavaScript Code

Running Python code on another server can be cumbersome. Here’s JavaScript code that can be run directly in a browser to get the results.

// decode
var rawcode = document.querySelector("#de_thunder").value.substring(10);

var decodedadd = window.atob(rawcode);
var decodedadd = decodedadd.substring(2,decodedadd.length-2); // Corrected line: 'substring' should be 'decodedadd.substring'
document.querySelector('#decoded').innerHTML = decodedadd;

// encode
var rawcode = document.querySelector("#en_thunder").value; // Removed .substring(10) since this is the input for encoding, not a thunder link
var encodedadd = window.btoa("AA".concat(rawcode,"ZZ"));
var encodedadd = "thunder://".concat(encodedadd);
document.querySelector('#encoded').innerHTML = encodedadd;

Conclusion

This article demonstrates how to encrypt and decrypt Xunlei links using both Python and JavaScript. You can also use the tool on Chunjiang Muker Xunlei Encryption and Parsing.