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China Censorship Communications The Internet

China's Censors Can Now Erase Images Mid-Transmission ( 90

Eva Dou, reporting for WSJ: China's already formidable internet censors have demonstrated a new strength -- the ability to delete images in one-on-one chats as they are being transmitted, making them disappear before receivers see them. The ability is part of a broader technology push by Beijing's censors to step up surveillance and get ahead of activists and others communicating online in China (Editor's note: the link could be paywalled; alternative source). Displays of this new image-filtering capability kicked into high gear last week as Chinese dissident Liu Xiaobo lay dying from liver cancer and politically minded Chinese tried to pay tribute to him, according to activists and a new research report. Wu Yangwei, a friend of the long-jailed Nobel Peace Prize laureate, said he used popular messaging app WeChat to send friends a photo of a haggard Mr. Liu embracing his wife. Mr. Wu believed the transmissions were successful, but he said his friends never saw them. "Sometimes you can get around censors by rotating the photo," said Mr. Wu, a writer better known by his pen name, Ye Du. "But that doesn't always work." There were disruptions on Tuesday to another popular messaging app, Facebook's WhatsApp, with many China-based users saying they were unable to send photos and videos without the use of software that circumvents Chinese internet controls. Text messages appeared to be largely unaffected.
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China's Censors Can Now Erase Images Mid-Transmission

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  • weChat is run by the govt
    • by Anonymous Coward

      Here below is my attached meme image response:


    • You do realize this means they have a CITM (computer in the middle. There aren't enough peeps to have an MITM or man in the middle of every internet connection). Once you find an image that is censored try sending it different ways with different communication methods. You will learn a lot. Does it get censored on Facebook messenger (does China allow FB messenger?). If so then FB gave them the encryption keys. Does the image get censored on a supposed secure SSL connection? If it does then think abo
  • by magarity ( 164372 ) on Tuesday July 18, 2017 @12:45PM (#54833503)

    Sufficient alterations such as running images through a "make it look like an oil painting" can probably get around this kind of detection. Although watch out for that "convert to cubism" option.

    • Take it a step further, and use steganography.

      • by XXongo ( 3986865 )

        Take it a step further, and use steganography.

        You mean encryption.

        steganography would be hiding bits within the image-- encryption would be hiding the image.

        • by Anonymous Coward

          Hide the bits that make the original image within a different image.

        • In this application, steganography is probably better. Encrypted data is generally easy to spot and ban - China has already banned VPNs. However, with steganography, you can have what looks like an ordinary picture containing the data for the picture that you actually want to send. Since this looks just like an ordinary image unless they block the transmission of all images it should get through.
    • by Anonymous Coward

      And then you can be "aggressively post-processed" by the Chinese government for subverting their censor.

      Scary stuff.

    • ASCII Art FTW! []

      • ANSI art is far superior.
        • Try this: convert myimage.png.jpeg.xpm.tif.whatever tmp.ubrl && tail -n+4 tmp.ubrl

          Then paste into any text medium that has been updated this millenium (ie, not Slashdot). Resolution is 2x4 per character, black&white only.

  • OMG... (Score:4, Interesting)

    by __aaclcg7560 ( 824291 ) on Tuesday July 18, 2017 @12:47PM (#54833521)

    What did Winnie the Pooh ever do to the Chinese government? []

    • by Anonymous Coward

      The good thing about Chinese censorship is that at least a billion people will be spared your ebooks. Can you imagine a Chinese kid learning English and the first thing they find is a cdreimer extravaganza? That'll make the Tyco suicides look like a walk in the park!

      BTW: How come you didn't provide any certificates of destruction for the hard disks on the 100 laptops you sold to a recycler? I bet future employers would like to know what you do with their property?

  • Well... (Score:5, Insightful)

    by Anonymous Coward on Tuesday July 18, 2017 @12:58PM (#54833597)

    ...guess it won't be long before this comes to the UK.

    For the children, don't you know?

    • by Anonymous Coward

      Well, yes. They have to protect the Muslims as they know they will be in power. It's a giant fucking race to cater to the new demographics so as to stay politically relevant. Sharia law is de-factor legal now.

  • in soviet russia we erase you!

  • by Anonymous Coward

    they should totally open-source this code.
    this way everybody can start erasing their own picture if taken by 3rd party and posted to facebook etc. without their consent.
    call it: "take-back-privacy"

  • Tell me, how do they intercept the data, figure out what it is - and how they get around disguising the data in so far as possibly stripping out any headers identifying file types, and the like for instance (without which, would seemingly just appear as a string of 1s and 0s).
    • by Anonymous Coward

      This is all done server-side.

      Wechat, the app in question, sends and stores all messages on Wechat's servers before broadcasting it to the intended recipients.

      According to various news reports, they've been able to trigger review of message via keyword-based messages for quite a while, and now they've apparently added the ability to filter videos and images by comparing them for similarities to banned images.

      One thing to remember about this is, Wechat is a major payment/messaging/blogging platform inside Chi

    • by dgatwood ( 11270 )

      I would not be at all surprised if sharing photos amounts to sharing the URL for the photo, in effect, in which case it can be blocked merely by blocking the URL (assuming no HTTPS).

    • it can't be that much harder than the upside-down-ternet: []

      when you have sufficient processing power.

      I've actually implemented this on a MITM proxy server with its trusted root certificate being installed via group policy so I could manipulate images on the fly and deliver things like downgraded image quality based on AD group membership. And its all HTTPS and the certificate checks out (on face value to the plebs, at least it doesn't give a warning in the browser) so thats ho

    • by AHuxley ( 892839 )
      The same way the NSA and GCHQ do it. A race track with consumer data going the long way around getting altered by faster gov/security services.
      FoxAcid, Turmoil, Quantum, QuantumInsert. Man-on-the-side, man-in-the-middle outpace any consumer network. Why just collect information on the way when the results can be changed too?
      Just as the NSA and GCHQ know all about peering, every server and service provider and the fast speed of their own tame telcos, so does China.
      The only way around that would be a go
  • If the story source is pay-walled (and here's an alturnative source), why refer and list the pay-walled link at all? Why not just use the alturnative source as the primary source?

    • by XXongo ( 3986865 )
      Because the alternative source is not the primary source. It is a mirror of the primary source.

      (Also, often the mirrors are on less-robust servers, so it's nice to have the primary source available for when the mirror inexplicably gets slashdotted.)

  • steganography? (Score:4, Insightful)

    by roc97007 ( 608802 ) on Tuesday July 18, 2017 @01:23PM (#54833769) Journal

    I'm curious if they've tried steganography to get around censorship? Hiding the photo inside another photo or document?

    Or maybe they *are* doing that, and the reason we're not hearing about it is because it's working.

    So... never mind...

    • by Falos ( 2905315 )

      Some, probably. The masses probably use easier "tricks" like rotation. Those are easier moles to whack, but it's still whack-a-mole and still futile and the tools of commoners will nestle in the classic feedback valley that balances 1) method difficulty, obscurity, resilience (whack cost); vs 2) likelihood/frequency of mole whack from Our Betters

      I've heard that they'll use substitute words to dodge filters. When they want to refer to a certain politician, location, event (tiananmen square?) they'll carefull

    • The technology is about suppressing what people of average intelligence get to see, not what people who are technologically sophisticated get to see.

      • You are absolutely right. That's an excellent point. So perhaps what's needed are some easy to use tools that allow average people to use sophisticated techniques.

        • by Anonymous Coward

          You are absolutely right. That's an excellent point. So perhaps what's needed are some easy to use tools that allow average people to use sophisticated techniques.

          Then, and therein lies the fun, whoever builds and distributes that tool is an enemy of the state.

          When the law is "whatever I say", there's no loophole.

          • You are absolutely right. That's an excellent point. So perhaps what's needed are some easy to use tools that allow average people to use sophisticated techniques.

            Then, and therein lies the fun, whoever builds and distributes that tool is an enemy of the state.

            When the law is "whatever I say", there's no loophole.

            I think one could argue that using any method to circumvent censorship by the glorious people's republic of China, including perhaps even rotating the image, could make one an enemy of the state. Why not go for the gusto?

    • Perhaps, but the sort of censorship we're seeing here is just a heavy-handed way of attempting to steer discussion on social media and chat apps. The other thing they did recently was remove is a load of foreign material [] from [], which is a Chinese video sharing site with subtitles and viewer commentary.

      If you really want to secretly share an image, there are a bunch of ways of doing that. What you're seeing with these recent actions are attempts to push around the most number of people with th

  • Tell me, how do they intercept the data, figure out what it is - and how they get around disguising the data in so far as possibly stripping out any headers identifying file types ...

    I know one way they could do it. People assume this censorship applies to everybody in China, but it could actually be restricted and implemented in a real low tech way that makes people think it applies to everybody when it only applies to a select few. Imagine a Man In The Middle approach. It seems logical to me that certain users are likely known by the government to post objectionable things from time to time, so if you don't have an exceptionally large number of such people to keep an eye on, you co

    • by pz ( 113803 )

      ... you could implement a MITM approach and send all their communications through a central party I'll call a "watcher" who sees the communication in real time and has the ability to pass on the communication untouched and also has the ability to edit out objectionable content before passing it on. Maybe the spied on person only uses WeChat for, say, 30 minutes, so the watcher moves on at the end of that to another user. You could just restrict the watchers to say 100 or maybe 1000 such people and if you make sure they watch the people who consistently post the most objectionable content ...

      A Scanner Darkly!

  • Once again, Mr. Munroe gets it right well before his time. []

  • Most fiction has the apocalyptic AI that takes over be of military origin, but I'm thinking it is going to be a Chinese AI that decides the best way to censor communications is to Kill All Humans.
  • Are you sure?

    Don't count on it.

    And you thought AI was your friend ...

Beware of Programmers who carry screwdrivers. -- Leonard Brandwein