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I wanted to do this but with Blu-ray’s. My goal was to build a library of every movie ever made that was worth seeing. It seemed like 2018 was a good time to do this since good movies have apparently stopped being made. Anyway, If you wanted to watch tons of good movies, you would normally end up paying tons of money to rent it from iTunes. And even then you only get to see it once and you have to have an internet connection. And streaming services don’t have even a fraction of the selection needed. But Netflix’s mail dvd service seems to have every movie I can think of. So why not open a few Netflix accounts, order disks in the mail and just save all the disk images? It seemed like a good idea until I looked into Blu-ray copy protection. Of course, I wanted to have my library consist of only the highest quality and highest fidelity so Blu-ray’s were called for. But Blu-ray copy protection is devious, ingenious and very effective. Each disk consists of two regions: A region that holds encrypted movie data and a region that holds a key. It is illegal for players to be sold that read the key and then forward it to user-facing interface like a computer. Players must always only read the key only in order to use it internally to decrypt the movie data. This stops all legitimate entities from selling players that reveal the key to the user. But what about the illegitimate entities that might want to sell modified players that provide the key? Or just publish keys online? Well, the key on the disk is itself actually encrypted. And it is encrypted in such a way that multiple keys can decrypt it. Blu-ray players come with special hardware that is flashed with a key at the factory. This hardware uses that key to decrypt the Blu-ray’s key. In the event that a key is compromised and published online, or used widely in any way, that key is depreciated and all Blu-ray’s from that point onward contain keys that cannot be decrypted with the compromised hardware key. Instead, a newer key is used. This new key is still able to decrypt all the old Blu-ray keys as well as all the new ones. This effectively defeats people publishing keys online. It’s ingenious in that the people who conceived it realized that the only time key compromise is a problem is when those keys are disseminated widely, and that when keys are disseminated widely they are easy for authorities to detect. If you want to get perfect rips of any blu-Ray you might come across, you are forced to go through the pain of probing the hardware yourself to get that key, which is quite difficult. There’s no way around it.



I’ve ripped every Blu-Ray I’ve purchased easily with MakeMKV, probably a couple hundred. I dunno, but someone is making it seem easy....


Like I said, makemkv (which is indeed the idiomatic tool for the job) will never be a reliable way to rip any bluray. For my purposes, it was very important to be able to rip absolutely anything I came across. If you’ve got some Blu-ray’s and want to try it out then fine. It will probably work if they are older movies and were “pressed” long ago. The Blu-ray copy protection scheme also has the quality of making legitimate players obsolete if they were the source of stolen keys. So even a legitimate older player might not be able to read a new Blu-ray.


> The Blu-ray copy protection scheme also has the quality of making legitimate players obsolete if they were the source of stolen keys. So even a legitimate older player might not be able to read a new Blu-ray.

This is the reason why I never bought a single player or disk, Blu-ray and HDMI/HDCP copy protection went way to far (especially with the chain of custody nonsense). At the end, if the industry wants to fuck legitimate customers like that, fine, I just torrent everything, this way only a single person/group has to figure out how to rip the disk or broadcast, just once. There is no reason what so ever to feel bad about it, they did it to themselves, no informed customer should ever buy into that shit. Its self defense, I'm not buying a TV for thousands for the copy protection to brick it eventually.


MakeMKV seems to have processing keys dating from late 2018 (at time of writing) so, ignoring BD+, it should be able to decrypt every disc pressed before then.


You may be right, but that doesn’t reflect my experience. Most the BR’s I rip are just barely released (pressed) and I have a 100% success rate with makemkv. They all literally worked on the first try, even new releases. Maybe I’m just lucky.

The only problem I’ve had is when they try to make it hard by putting a gazillion titles on the disk to make it hard for you to figure out which is the right one. That sucks, but is not insurmountable.


This has been my experience too. I've never had makemkv fail to open something. I suppose that if the dude who runs it ever gets hit by a bus or something, then it might not be useful going forward from then, but presumably somebody else would take up the work.


As long as you dump the encrypted key, you can reliably trust that there will become a way to decrypt it later.

> In the event that a key is compromised and published online, or used widely in any way, that key is depreciated and all Blu-ray’s from that point onward contain keys that cannot be decrypted with the compromised hardware key.

If someone merely provides a title key decryption API, is there any way to figure out which device key they're using?


Wow I had not actually thought of that. Hosting that service would cost money, unlike releasing keys on pastebin, and any attempt to do something like this, especially if monetized, would meet considerable retaliation from Blu-ray people. So I guess that’s why you don’t see it.

Getting keys from your hardware is a hassle and I didn’t want to wait for a decryption solution later.


Would that service really take more than a raspberry pi on tor?


Hmm... web/bittorrent over tor, with update file references. Just have the swarm on a given directory, update to the latest "full" swarm every day/release with the same directory for the keys available.


Yeah (DoS factor).


Just hold on to the discs you can't rip. Eventually enough keys will be leaked to decrypt them. Blurays will likely die out when internet is fast enough to stream high quality video and at that point you will be able to rip them all when a key is leaked.


Internet is already fast enough to stream high quality movies. The reason you can only access a comprehensive list of movies thru iTunes or disks is legal, not technological.


Not at BR quality. Well, it may be fast enough in sections, but it isn't economical to send out thousands of BR quality streams, so they don't.

Newer codecs help with that, yes. However, streaming will not be as high quality as a "station wagon full of tapes" i.e. local, in the near future.


Easily at BR quality with a high speed connection — it's only 20-30 mbps — but as you say, consumers don't care enough to pay what it would cost to stream at higher bitrates.


Really? Most people still use internet slower than 10 Mb/s and treat a computer as an enemy that works against them.


Source? I don’t know if any isp that still offers 10mbit service.


Come out to Western Montana. CenturyLink would only offer 10mbps/1mbps, of which I was lucky to get about half. They let me upgrade last month to 25/2, of which, I am lucky if a speed test results in 10/1.5. I'll take it as it is quite literally the best I can get. I recently paid Spectrum around $5k to extend a line to my house, but I'll have to wait until spring for it and its 400/25 (I am counting the days!).


Haha, come to Australia. That's faster than the connection my whole office at work shares. I don't know anyone who could stream a bluray which is usually about 40gb for an hour of video.


https://o2.cz

My top speed is 8 Mb/s. This is the most prominent provider in my country. My plan is 20 Mb/s, but that has literally never happened. A lot of people in my country use wifi providers with outdated equipment, giving them around 10 Mb/s as well. And lastly, check the page on average speeds of the Internet on Wikipedia.

BTW the absolute majority of customers are sharing their bandwidth and the infrastructure is built with that in mind. If everyone streamed 4K videos, the actual speed would go down massively - of course since the only solution would be to rebuild the infrastructure, that is not going to happen, instead they will lower the speed or introduce FUP.

You can see Czech Republic pretty high in that list - that's because it's average speed, not median. I have a friend that has a 600 Mb/s plan that's 3 times cheaper than mine, but that's not the norm - and I guess it's similar all around the world, either you're lucky... or not.


I am half hour from a major metro, I would gladly pay another 80/mo to have 1.5m on a semi reliable basis. You take a lot for granted. Our infrastructure sucks ouside the suburban bubble.


Wow I'd forgotten how lucky I am right now--that's what I pay for gigabit fiber. Thanks for the perspective.


Pretty standard in the UK outside of major towns/cities.


Not that uncommon outside of major towns/cities either - I was getting barely 12Mbps on ADSL in inner London, and that only 600m from an exchange.


ADSL speeds aren't great, but fibre is available almost everywhere in cities in the UK...


True. Although even on fibre, I only get 25Mbps peak. Often it's hovering around 18-20Mbps (which is not quite enough for 4K streaming, IIRC.)


Of course that's fake fibre aka fibre to the green cabinet in your street. The UK allows that to be marketed as fibre despite the large difference in performance to a real fibre connection.


Having since upgraded to real fibre (I saw the man splice it into the router connector with my own eyes), the difference is staggering - now I regularly get 500Mbps+ up and down with not infrequent 800Mbps+.


And even that is surely not just for you, but shared.


Why not just read the unencrypted data that the Blu-ray players give you, though.


Like, ripping the HDMI output? You're limited to realtime speed for that, which is going to make the process take ten times longer.


Plus, critiacally, that signal is the result of the player messing around with the data. It might do all kinds of stupid processing. You don’t know what quality of decoder they’ve put in the player. I guess there are ways to find out so It’s not a dealbreaker but it’s just another thing that complicates stuff. But overall I’d say that finding a player with really good decoding and capturing the resulting signal is your best option for the scenario I outlined. It wouldn’t make a difference if it took 2 minutes or two hours because the window between getting a movie and mailing it back is way more than two hours.


> But overall I’d say that finding a player with really good decoding and capturing the resulting signal is your best option for the scenario I outlined.

Exactly.


Also HDCP becomes an issue.


You can get HDMI splitters on Amazon that will get rid of HDCP.


I’ve ripped a few of my own BR discs, hasn’t been a insurmountable problem.


You make it sound like you cracked the disk encryption or lifted keys off your player. Or did you just try out keys you found online?


Nope, just used Handbrake. It uses whatever library that handles BR decoding and key management. I believe sometimes a key hasn't yet been leaked on newer discs, however if you wait a few months it will have.




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