Help with downloading encrypted HLS video for offline viewing

[danaew]

Hi all, I've had interest in downloading some study videos from a site but they all turned out to be encrypted HLS so I've been running into some difficulties. I read this thread which kind of got me in the right direction, but I couldn't find the key for the video. I also stumbled upon a GitHub project which apparently does exactly what I want, but I couldn't get it to work... So I turn to you! I appreciate any help I'll receive

Video link

[lomero]

1080p

https://www.upload.ee/files/16476160/Learn_German_h264_1080.mkv.html

[danaew]

1080p

https://www.upload.ee/files/16476160/Learn_German_h264_1080.mkv.html

Hey, thanks a lot! If it isn't too much trouble, could you explain how you downloaded the video from the site?

[lomero]

rip cookies, save as cookies.txt, then:

yt-dlp "https://m3u8" --cookies cookies.txt -o video.mkv

[mister_ nex]

hlsdl -K "a6d06cd55c1966dd1cc0939c451239ad" "https://proxy2.ucha.se/uchase/_definist_/smil:videos/06082020-Zashto-da-ucha-nemski/stream.smil/chunklist_b1054768_slbul.m3u8?ut=wqeoBtn2Hu2dCAgn68H7"

[aqzs]

hlsdl -K "a6d06cd55c1966dd1cc0939c451239ad" "https://proxy2.ucha.se/uchase/_definist_/smil:videos/06082020-Zashto-da-ucha-nemski/stream.smil/chunklist_b1054768_slbul.m3u8?ut=wqeoBtn2Hu2dCAgn68H7"

I would like to understand how you got the key.
I got the playlist.m3u8 then chunklist_b1054768_slbul.m3u8
I got this line

#EXT-X-KEY:METHOD=AES-128,URI="https://ucha.se/streaming/key/?ut=wqeoBtn2Hu2dCAgn68H7"

and a request to this server give me :

длlН\fП└ЊюE9Г

which im not able to parse to get

 a6d06cd55c1966dd1cc0939c451239ad

Could you help me to understand how you reverse-engined ?

[white_snake]

I would like to understand how you got the key.
I got the playlist.m3u8 then chunklist_b1054768_slbul.m3u8
I got this line

#EXT-X-KEY:METHOD=AES-128,URI="https://ucha.se/streaming/key/?ut=wqeoBtn2Hu2dCAgn68H7"

and a request to this server give me :

длlН\fП└ЊюE9Г

which im not able to parse to get

 a6d06cd55c1966dd1cc0939c451239ad

Could you help me to understand how you reverse-engined ?

See here: https://forum.videohelp.com/threads/413718-My-journey-with-AES-128-encrypted-HLS

[mister_ nex]

Could you help me to understand how you reverse-engined ?

Use the Firefox browser - it immediately shows base64 value

https://ucha.se/streaming/key/?ut=wqeoBtn2Hu2dCAgn68H7

[Attachment 78121 - Click to enlarge]

ptBs1VwZZt0cwJOcRRI5rQ==

then convert base64 to hex

https://base64.guru/converter/decode/hex]

[aqzs]

Thank you @white_snake, i read the threads on 1st april and new messages arrived.
I get the response from the server with python so directly in base64, then I do :

binascii.hexlify(response.text.encode('utf-8')).decode('utf-8')

and I get :

d0b4d0bb6cd09d5c1966d09f1ce29494d08ad18e451239d093

Then :

hlsdl -K "d0b4d0bb6cd09d5c1966d09f1ce29494d08ad18e451239d093" "https://proxy2.ucha.se/uchase/_definist_/smil:videos/06082020-Zashto-da-ucha-nemski/stream.smil/playlist.m3u8"
Error: AES key value : 32 characters hexstring expected
hlsdl v0.27

[aqzs]

(I'm not able to use

base64.standard_b64decode(response.text).hex())

because I get :

ValueError: string argument should contain only ASCII characters

but that's weird since im directly curling the server so the response should be in base64 ?

[lomero]

go to https://base64.guru/converter/decode/hex

put base64 ptBs1VwZZt0cwJOcRRI5rQ==

in hex you get a6d06cd55c1966dd1cc0939c451239ad


[Attachment 78122 - Click to enlarge]

[Obo]

Or in Python:

import binascii, sys, base64
print(binascii.hexlify(base64.b64decode(sys.argv[1])).decode())

[aqzs]

So I feel dumb I just sould use :

print(response.content.hex())

Im finally getting a6d06cd55c1966dd1cc0939c451239ad ! Thank you to everyone, you've all been helpful !!

[mister_ nex]

I get the response from the server with python so directly in base64

Could you please explain what commands you use to get a response from the server?

https://ucha.se/streaming/key/?ut=wqeoBtn2Hu2dCAgn68H7

[aqzs]

I get the response from the server with python so directly in base64

Could you please explain what commands you use to get a response from the server?

https://ucha.se/streaming/key/?ut=wqeoBtn2Hu2dCAgn68H7

Yes so I copy the curl request from the web inspector as cURL

[Attachment 78123 - Click to enlarge]
The I paste in vscode so I get the headers and everything (using vscode extension from https://curlconverter.com/):
[Attachment 78124 - Click to enlarge]

import requests
headers = {......}
response = requests.get('https://ucha.se/streaming/key/?s=....&ut=wqeoBtn2Hu2dCAgn68H7', headers=headers)
print(response.content.hex())

And it return the key !

[mister_ nex]

Thank you for the explanation! I will try this method.

[mister_ nex]

aqzs
I created a script, ran it, but no response

import requests
headers = {'accept': '*/*',
    # 'cookie': 'PHPSESSID=798qq6539631u3kesfr4k272lb; cookie_tooltip=2',
    'referer': 'https://ucha.se/watch/10623/zashto-da-ucha-nemski',
    'sec-ch-ua': '"Google Chrome";v="123", "Not:A-Brand";v="8", "Chromium";v="123"',
    'sec-ch-ua-mobile': '?0',
    'sec-ch-ua-platform': '"Windows"',
    'sec-fetch-dest': 'empty',
    'sec-fetch-mode': 'cors',
    'sec-fetch-site': 'same-origin',
    'user-agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/123.0.0.0 Safari/537.36',}
response = requests.get('https://ucha.se/streaming/key/?ut=wqeoBtn2Hu2dCAgn68H7', headers=headers)
print(response.content.hex())

.

[aqzs]

You have to provide s=... in the request. The value is in the webpage in 'data-params' so can be parsed using python.
You also have to give the PHPSESSID in the header. The minimal code provider here should be working :

import requests
headers = {'cookie': 'PHPSESSID=84rk8ea1ue8keod6i3muohepif',}
response = requests.get('https://ucha.se/streaming/key/?s=VALUE', headers=headers)
print(response.content.hex())

VALUE = aaa23b05671b0b3babe682e6f08dd6f1 for this vid

[mister_ nex]

import requests
headers = {'cookie': 'PHPSESSID=84rk8ea1ue8keod6i3muohepif',}
response = requests.get('https://ucha.se/streaming/key/?s=VALUE', headers=headers)
print(response.content.hex())

Thanks for the clarifications and advices! The script produced the correct result.

[Attachment 78128 - Click to enlarge]

You have to provide s=... in the request.

Apparently I was in a hurry and entered the wrong link.

[mister_ nex]

Or in Python:

import binascii, sys, base64
print(binascii.hexlify(base64.b64decode(sys.argv[1])).decode())

Unfortunately, it was not possible to use your script.


[Attachment 78146 - Click to enlarge]
Tried another script

import base64
text = 'ptBs1VwZZt0cwJOcRRI5rQ=='

dec = base64.b64decode(text).hex()
print(dec)

v.Python 3.10

[Attachment 78147 - Click to enlarge]