Microsoft sends GitHub DMCA shutdown for Skype open source project

https://github.com/github/dmca/commit/db9b442f0ac68512d0ca83fe7b25a7f9bf766e63

by ecaron • 14 years ago

189 90 14 years ago

ecaron• 14 years ago

This project was recently discussed on HN at http://news.ycombinator.com/item?id=3899829

martey• 14 years ago

You linked to a discussion of a tool that lets you lookup the IP addresses of Skype users (which seems like it might have been developed with this tool), but I think you meant to link to https://news.ycombinator.com/item?id=3753155

mseebach2• 14 years ago

Better link: https://github.com/github/dmca/blob/db9b442f0ac68512d0ca83fe...

cies2• 14 years ago

even better link:

https://github.com/github/dmca/blob/db9b442f0ac68512d0ca83fe...

(rendered into human readable)

mseebach2• 14 years ago

That is the exact link I posted?

skypeopensource11• 14 years ago

Read it please.

Demand for Immediate take-Down: Notice of Infringing Activity URL: https://github.com/downloads/skypeopensource/skypeopensource...

Its not to repo code. Its for patched binary, yes.

Canuteson• 14 years ago

So I guess they should rename it Skipe open source.

coderdude• 14 years ago

The name falls under trademark protection and is not related to copyright.

uxp• 14 years ago

"Skype: patched and recompiled to do other stuff" is a better title. Decompiling a proprietary product, changing a few lines of code, and then releasing that code doesn't make it "open source", it makes it stolen code (semantics of "piracy is not theft" aside, it's still not his code to be releasing in it's entirety.).

skypeopensource11• 14 years ago

You are wrong. Decompiling is just allowing research deeper in skype-black-box. Project itself is here https://github.com/skypeopensource/epycs

Xuzz2• 14 years ago

Please note: this is not an attempt to clean-room reverse engineer Skype, or even to reverse engineer and create an open-source replacement. As shown with things like WINE, Microsoft does not (and probably cannot) take them down.

No, that's not what "Skype Open Source" project is. This is a confusingly misnamed attempt to attach code to patched copies of copyrighted official Skype clients.

Microsoft is not overreaching here; this is what anyone would expect with a lame project like this. I'd love if someone really created an open-source Skype client, but this is not a project to do that.

ajross• 14 years ago

Are (were) they distributing the patched binaries or just the tools to do it?

cube13• 14 years ago

It's hard to tell. The author is clearly not too fluent with English, so it's difficult to tell exactly what he's saying. It sounds like it's based on a decompiled and recompiled version of the core Skype kernel dlls and not a clean room implementation.

Muromec• 14 years ago

There was deobfuscated version of skype 5.5 in downloads section of project. Not in repo.

Code in repo contains reimplementation of skype protocol (RC4 chiper, 41 and 42 encoders) and sample tool capable of sending IM to skype peer.

There also was some tools for extracting user certificate from skype profile.

Iv8• 14 years ago

How exactly is one supposed to make a clean-room reverse engineering in the absence of any documentation and sophisticated obfuscation on Skype's part ?

wmf• 14 years ago

It's hard, but people have made progress with that approach:

http://recon.cx/en/f/vskype-part1.pdf http://recon.cx/en/f/vskype-part2.pdf

option_greek• 14 years ago

Usually, that would mean reverse engineering to create specifications and then getting the product implemented by some one else using the specification which would then be termed as clean.

recoiledsnake3• 14 years ago

Maybe then you're not "supposed" to do it?

For example, there is no reverse engineered libraries for Facetime and iOS API. If you use Apple's libraries, they can come after you for copyright infringement.

danbmil993• 14 years ago

Seems like you could do it in theory by observing the protocol in action. Set up two machines a-skyping, sniff all the packets, think real hard, write code that interoperates with Skype clients.

skypeopensource11• 14 years ago

You are wrong. You eyes are blind by hating. Stop. Listen the Nature.

Skype-open-source code here: https://github.com/skypeopensource/epycs

repo was closed because i host in download section deobfuscated skype5.5 binary, my fault.

daeken• 14 years ago

No, that's bullshit. https://github.com/skypeopensource/epycs/blob/master/sources...

That function right there (and the vast majority of the rest of the file) is a straight decompiled version from Skype. You even use the register names and comment with addresses from the binary.

Having spent a lot of time reversing apps myself, this is a straight copyright violation. Your code is a directly derivative work from Skype.

jimueller• 14 years ago

This seems legitimate and they are well within their right to do this as the copyright holder.

ldng• 14 years ago

If I am not mistaken it's not the first time Skype send a DMCA to this project. But given where the autor lives, the DMCA does not apply so it doesn't go anywhere.

seldo• 14 years ago

AFAIK the DMCA takedown applies to Github, who are in the US, regardless of where the author of the project lives.

nextparadigms• 14 years ago

So much for Microsoft loving the open-source movement.

kcbanner• 14 years ago

heh, did you look at the project? It's not open source, it's a decompiled Skype binary.

skypeopensource11• 14 years ago

No, its not. Decompiled binary just need for reversing. Open source clone of skype is Epycs(reverse enginered skype). https://github.com/skypeopensource/epycs

recoiledsnake3• 14 years ago

I guess Google too hates open source since they won't release their proprietary modifications to the Linux kernel and their search engine code and will go after anyone getting them and putting it on Github.

tonfa4• 14 years ago

http://git.kernel.org/?p=linux%2Fkernel%2Fgit%2Ftorvalds%2Fl...

PuercoPop• 14 years ago

The authors website is http://skype-open-source.blogspot.com/

Apparently he had already been served with DCMA takedown requests. And talks about deofuscation. Doesn't sound like a cleanroom implementación.

skypeopensource11• 14 years ago

Now, we are working on stage1, make working code and do specification. Takedown was because of patched binary which reversers used as black box for make specifications.

tonycoco2• 14 years ago

MS can't catch a break... They defend their copyrights and get slammed on Hacker News for not being "cool" with the OSS community infringing on their properties. Weak sauce, Hacker News.

J3L2404• 14 years ago

PG has declared all copyright null and void.

VMG• 14 years ago

I think you are being downvoted because you forgot the qualifier "if it is too difficult to enforce"

eli3• 14 years ago

Where do you see people slamming Microsoft in this thread?

tonycoco2• 14 years ago

The post of this just implied, to me, that Microsoft is evil for putting in a take-down request. Why else post this? There are literally hundreds of take-down notices on GitHub. Why post this one?

cooldeal4• 14 years ago

Here? http://news.ycombinator.com/item?id=3919881

getsat• 14 years ago

Was the code mirrored anywhere offshore before the takedown? Could someone re-host it?

skypeopensource11• 14 years ago

Rehosted to https://github.com/skypeopensource/epycs

snarkinatree3• 14 years ago

How about "Skype: The Missing Technical Manual"?

MS will contribute nothing to the state of the art of free voice and video calls over the internet. As is so often the case, what they purchased with the Skype deal was a user base. One that they could never obtain with the own products.

There is a way to do this without violating copyright.

Do not waste time duplicating the P2P element of Skype (the P2P protocol). P2P protocols have been done, several ways, some of them are easily good enough, maybe even smarter than Skype's (e.g., avoiding the exposure of your IP to the entire internet) and enough of the code is GPL'd or BSD licensed to keep things open. We have ample solutions for P2P. View that as the "open platform".

Now you need "apps" to run on it. First one is a softphone, but with Skype's codecs.

Focus on creating a standalone softphone using Skype's codecs.

Does MS have exclusive rights (patent rights) on Skype's codecs? Not even close. They did not develop them. The patent license could fit on a single page; it's as simple as they come: build stuff, pay nothing.

http://developer.skype.com/silk

danbmil993• 14 years ago

If you don't want to be compatible with Skype, you don't need their codecs. There are plenty of good voice codecs around, freely licensable.

The issue is how to tap into the existing Skype userbase -- receive and make calls to Skype clients -- from an open-source client.

snarkinatree3• 14 years ago

I agree tapping into the existing userbase is enticing. And that's no doubt what some people are trying to do (e.g. the Russians).

But all VOIP codecs are not created equal. Skype's success is not due to NAT piercing. Even though Skype easy to use, maybe easier than previous SIP alternatives, if calls sounded terrible, people would not use it. Skype's success is due to being usable and having decent sound quality. They did not use the decades old codecs other softphones used. They wrote new ones. And anyone can use them.

Using the same codec as Skype uses should not in any way bind you to their network. It has nothing to do with compatibility. It has to due with getting Skype-level sound quality. Quality that the older codecs have failed to deliver.

It's easy to get people to sign up for free voice and video calls. The key word is "free". You do not have to find inroads into the "Skype user base". Skype spread by word of mouth. If people learn about another client that works as well or better (same sound quality), and it's easy to use, they will almost certainly try it.

Forgive me if I have misunderstood what you were trying to say in your comment. But I do not understand your reasoning.

jahewson2• 14 years ago

Yes, they purchased users, but also a lot of patents which go far beyond codecs http://www.google.com/search?tbm=pts&tbo=1&hl=en&...

xnm• 14 years ago

This probably has something to do with this exploit: http://pastebin.com/yhcrRSVh

ajasmin• 14 years ago

Can someone explain why Microsoft would go to such length obfuscating the Skype code and taking down derivative work?

Is their IP worth the trouble? Do they see interoperability as a threat? Are they afraid of misbehaving clients?

Surely it's not just a case of a lawyer having too much time on his hands.

skypeopensource11• 14 years ago

We are appreciate you help on working on Epycs - reverse engineer skype project.

Feel free to study current implementation stage here - https://github.com/skypeopensource/epycs

skypeopensource11• 14 years ago

This is first stage of 'clean room' reversing process - writing specification.

Microsoft sends GitHub DMCA shutdown for Skype open source project

Related Stories