If its linux based give the communinty a chance to look at the code [Archive]

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elas123

01-10-07, 07:10 AM

Stuart Sweet

01-10-07, 07:25 AM

Earl if the security is in place, cant directv make the source code available for people to look at and maybe give suggestions or correction. This maybe stupid but maybe there are ppl here that could see problems!

In a perfect world, this would be a great solution. I just don't think there's a NDA strong enough to cover releasing the source code on a developing retail product.

Doug Brott

01-10-07, 07:52 AM

I don't know the answer to this, but here is my speculation:

I'm almost positive that the HR20 uses the Broadcom BCM7038 as the CPU. This chip has some decoding capabilities. In addition, the HR20 has the BCM7411 for the primary MPEG4 decoding operations. I also believe that DirecTV uses some "retail" version of Linux that runs on the BCM7038 processor which would mean that they wouldn't have any legal reason to release the source code.

Earl Bonovich

01-10-07, 07:57 AM

Let's put it this way.

The Chicago Cubs would have to be playing the Chicago White Sox in the world series... for a game 7 that goes 37 innings... and the Major Leagues call it a tie... before you see the source code for the HR20... ;)

Stuart Sweet

01-10-07, 08:01 AM

Not quite sure what you're saying, Doug --

If it's Linux or some other X flavor, then sure we could all get the OS pretty easy, but I think that it's the HR20-specific code that's really the issue, not the core OS. Just because it was built on an open-source OS doesn't mean that the HR20 code is open source or protected by GPL.

Sure I'd love to get my hands on it and see what's wrong but what's to stop me from customizing it to my heart's delight? With enough time I'd figure out how new firmware gets loaded, write my own and put it on the HR20. I think we've seen D*'s stance on hacking, and [given this forum's rules] I understand.

Doug Brott

01-10-07, 08:10 AM

Not quite sure what you're saying, Doug

Let's just say I agree with Earl. Anything that DirecTV has that should be Open is probably from somewhere else (my speculation). Anything that DirecTV has created on their own, no way in .. well, you get the picture. :)

Spanky_Partain

01-10-07, 08:23 AM

Then we could blame each other instead of the common love/hate relation we currently have with D* if we got our hands on the code! :lol:

Even though it would be fun to poke around in the code and give suggestions on where things might could use some tweaking, think of it as your 5 year old talking to you at the same time you are trying to get a bid out on a job that will make you or break your business. D* won't give you check-in capabilities and the developers have enough on their plate instead of trying suggestions from individuals who don't have the BIG PICTURE information. Would be fun though!

Should it be open source? I can tell you right now, there are good reasons why everything is not open source. Somebody comes up with a HD chipset that has FLB buffers, four channel PIP in HD, internet download capabilities, retrieve anything from your server and use it, and it only costs $299. The only thing you need is the code to do all this on your hardware. You got the code and it is open source. Guess who will be building and selling the product? Anybody who wants too!

Anyway...
Here is a link to the Broadcom BCM7038 if you want to take a look at it...
http://www.broadcom.com/collateral/pb/7038-PB01-R.pdf

solo1026

01-10-07, 08:37 AM

dewalt

01-10-07, 09:24 AM

If it was linux, with a most likely modified kernel, wouldn't they have to publish their changes? I know Tivo does.

linuxworks

01-10-07, 09:36 AM

If it was linux, with a most likely modified kernel, wouldn't they have to publish their changes? I know Tivo does.

they should have to. but that is not the value-add, I don't think.

talking to their custom chips, THAT is value add.

decrypting all that encrypted mess - THAT is value add. and people would just LOVE to be able to see the logic of how to decode satellite streams! ;)

you'd need (maybe) an ICE or at least a logic analyzer (it IS am embedded system, afterall) to fix tough problems. you'd need a lot of things to really be effective in hacking and fixing things.

someday, HD will be 'broken' (figured out) and then we can get around all this HDMI protection nonsense, be able to use a regular old linux pc to do our recording and playback, etc. we can do all that today with SD - but the media companies are trying their best to have the HD generation NOT have the same freedoms that we won for ourselves, before.

give it time. for me, the commercial products that do dvr are just a stop-gap measure until the encryption from cable cards and so on is broken and we can finally have control restored back to us, the consumers.

but in the meantime, expect a big fight. heck, I can't even get dvi->hdmi to run my lcd tv at full native res. I have to fallback to vga (sigh) since the vendors and standards bodies built in a layer of politics in the tech standards for HD ;(

I am only with the set top boxes for as long as I have to. I do dream of the day when we can have the same freedoms on HD that we 'enjoy' on SD.

Earl Bonovich

01-10-07, 09:39 AM

I do dream of the day when we can have the same freedoms on HD that we 'enjoy' on SD.

It's not an HD vs SD thing

It is an Analog vs Digital thing.

Just so happens that HD is broadcasted in the Digital arena.

macEarl

01-10-07, 09:48 AM

If it was linux, with a most likely modified kernel, wouldn't they have to publish their changes? I know Tivo does.

Isn't that only for GPL'd content? Just because something runs under GNU/Linux doesn't mean it's open source. If you develop in gcc, I think the only requirement is to not strip the object files - but it's been a long while...

Spanky_Partain

01-10-07, 09:50 AM

If you feel like reading a long article from the considered "experts" about open source, the comparisons, and where it is heading, then take a look at this link...

http://catb.org/~esr/writings/world-domination/world-domination-201.html

Basically, he is promoting closed source on certain things, such as drivers, so new hardware can be introduced to Linux faster without having to provide source to avoid the "tainted kernel".

chrisfowler99

01-10-07, 09:57 AM

Earl Bonovich

01-10-07, 10:07 AM

So you're saying there's a chance...

There is always a chance....

elas123

01-10-07, 10:12 AM

but if the box updates itself, directv has ultimate control over the software being installed. if they have the right security inplace. the box will know if modified software is on the box and update accordingly. jsut a thought

Earl Bonovich

01-10-07, 10:14 AM

elas123

01-10-07, 10:16 AM

earl what with having to replace the chip to mod it?

Earl Bonovich

01-10-07, 10:21 AM

earl what with having to replace the chip to mod it?

Yep... That is why you have to replace the prom chip in the R10... to stop it from replacing the modified code segments.

And that is as far as I want to "delv" into that topic... ;)

Tom Robertson

01-10-07, 10:26 AM

Another thing to also consider. Unlike some companies where any developer can look at all the code in an application, Directv has IP that must be very carefully protected (namely the DRM) that some people have paid huge $$ to break. I've read stories of people taking their BUD STB from scientific atlanta to labs with electron microscopes to figure out how they work! (Actually some cool articles, :) )

So I would not be surprised if Directv is more compartmentalized. There very well could be sections of the code that very few people are allowed to see. (Especially anything involving decoding, decrypting, PPV, etc.)

I think Earl has overestimated the odds in his example. :( The Cubs and Sox might some year actually see each other in the WS.

Though it was a very good indicator of the ballpark odds...(yeah, shoot me, pun was intended, I need to go back to my cage again.)

Cheers,
Tom

marty45714

01-10-07, 12:56 PM

Quoting Lloyd Christmas from Dumb and Dumber: "So you're saying there's a chance!!!!!!!!!!!" !rolling

Dammit, someone already posted this earlier and I thought I was being funny! Oh well!

Let's put it this way.

The Chicago Cubs would have to be playing the Chicago White Sox in the world series... for a game 7 that goes 37 innings... and the Major Leagues call it a tie... before you see the source code for the HR20... ;)

dewalt

01-10-07, 03:28 PM

Isn't that only for GPL'd content? Just because something runs under GNU/Linux doesn't mean it's open source. If you develop in gcc, I think the only requirement is to not strip the object files - but it's been a long while...

I simply meant that if they modified the Linux kernel, wouldn't they be required to publish the changes for the kernel? It has nothing to do with the directv app. I'm just basing this on what Tivo has done (or thought was required to do).

BobV

01-10-07, 03:55 PM

I wonder how much of the flash rom is used up by D?

Will they run out of room soon?

There is only so much software you can put on a chip!!:grin:

macEarl

01-10-07, 08:06 PM

I simply meant that if they modified the Linux kernel, wouldn't they be required to publish the changes for the kernel? It has nothing to do with the directv app. I'm just basing this on what Tivo has done (or thought was required to do).

It's under GPL; although not recent, available for review is:
http://www.linux-watch.com/news/NS8169678991.html

So, I'd say yes. Then there's a whole can of worms over non-GPL'd kernel modules; however, this isn't the place and I'm no expert.

mateom199

03-17-07, 01:05 AM

As far as I understand,

a) Distributing any linux variant requires at the very least also distributing a copy of the gpl license.
b) Even if DirecTV is using a "retail" linux - ie, non-custom, it still must release the source code upon request.
c) Like Tivo, ONLY the kernel source must be released, not their custom modules which would undoubtedly hold their proprietary code for their encryption, etc.

From the FSF (http://www.fsf.org/licensing/licenses/gpl-faq.html):
Does the GPL require that source code of modified versions be posted to the public?
The GPL does not require you to release your modified version. You are free to make modifications and use them privately, without ever releasing them. This applies to organizations (including companies), too; an organization can make a modified version and use it internally without ever releasing it outside the organization.

But if you release the modified version to the public in some way, the GPL requires you to make the modified source code available to the program's users, under the GPL.

Thus, the GPL gives permission to release the modified program in certain ways, and not in other ways; but the decision of whether to release it is up to you.

and

Why does the GPL require including a copy of the GPL with every copy of the program?
Including a copy of the license with the work is vital so that everyone who gets a copy of the program can know what his rights are.

It might be tempting to include a URL that refers to the license, instead of the license itself. But you cannot be sure that the URL will still be valid, five years or ten years from now. Twenty years from now, URLs as we know them today may no longer exist.

The only way to make sure that people who have copies of the program will continue to be able to see the license, despite all the changes that will happen in the network, is to include a copy of the license in the program.

and finally
Can I release a modified version of a GPL-covered program in binary form only?
No. The whole point of the GPL is that all modified versions must be free software--which means, in particular, that the source code of the modified version is available to the users.
Bottom line is, no matter what flavor/variant/type of linux being used, if DTV are using Linux, they are not following the GPL. They at least have to acknowledge the fact that they are using GPL'd code.

Feel free to correct me if I'm wrong, I'm not a GPL expert.