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326 lines
22 KiB
Plaintext
Audience: General, people who stumble upon gnu.org
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1924+/-395 words english
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1028+/-395 words instead?
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755 words rahisibhasha
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stab at french
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Version: 2019-05-29
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#########################################
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大云墙 (Dà Yún qiáng)
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大きな雲壁 (Ookina Kumo kabe)
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The Great Cloudwall
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by Jeff Cliff
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essistensa una reason you go to
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#########################################
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There is a reason that none of your favourite work has appeared on Tor since early 2016[15].
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That reason has lead to the discovery of a threat to the operation of the World Wide Web.
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Prerequisites:
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- The JavaScript Trap[47]
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- Understanding that Google is not to be trusted[45][46]
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- Nick Szabo: "Trusted Third Parties are Security Holes"[44][48]
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Cloudflare is a network service for turing tests its users use against visitors, which means that it frustrates attempts
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by users of its users to develop software to interact with their websites[3].
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This might seem strange at first - why would you need a program to access a web resource?
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But there's many things that work on the web like this, including RSS, streaming, chat, podcasts, and anti-virus definitions[57][58] which
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are completely broken by a CAPTCHA appearing mid stream[11].
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"We humans don't make HTTP requests, our machines to do it for us."
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This makes clear what is really being tested here - whether or not you have the right software stack in between you and
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Cloudflare.
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This is not hypothetical: Cloudflare is currently attempting to dictate which browsers users of their "protected"
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websites may use[60].
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{{expand}}
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Your right to use Free Software in this stack is at risk and could disappear at any moment.
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It also is extracting free labor from website users[35], in effect tricking humans into acting like robots in order to
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pass a test designed to see whether or not they are a robot. Worse, this labor is being used to train[62] Google's artificial intelligence, a very
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poor candidate for "friendly AI"[36]. Given unfriendly AI is an existential[43] risk[42] to mankind, avoiding this
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should be among the highest of priorities.
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This software stack includes human language: the CAPTCHAs are in English, leaving non-English speakers around the world
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at a disadvantage[13]. Attempts to fix this are bound by the fact that they also leak language information to
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Cloudflare[21].
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Furthermore, they use Google's reCaptcha for their turing test/"proof you are a human" challenge and Google is known as a part of NSA's PRISM surveillance project so they expose their website visitor's data to PRISM data collection.
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On its own, this is terrible bad but it's also worth pointing out how the reCAPTCHAs work. It isn't by whether or not you
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click on the correct icon (though that is a factor too) but also collect:
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> mouse movement, its slightness and straightness
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> page scrolls
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> time intervals between browser events
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> keystrokes
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> click location history tied to user fingerprint
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> device information
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> All these criteria are stored in the browser’s cookie and are processed by Google’s servers
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> It should be emphasized that there is DARPA technology to identify people by mouse movements and typing
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[23]
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This collection of data is likely illegal in regions where privacy is taken seriously (like the EU)[24].
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It is frustrating even when it works because you have to fill out 20 captchas on the off-chance that you succeed one time in
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twenty. So this is 95% censorship and 5% wasting users' time[5].
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More important, though, is that it starts to form a ratchet for web browser technology; the captchas are upgraded all the
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time and if you use an older browser, you risk being left behind even when it works.
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*How Cloudflare Threatens You*
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"When you fetch a page from a website that is served from Cloudflare, JavaScript has been injected on-the-fly into that
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page by Cloudflare. And they also plant a cookie that brands your browser with a globally-unique ID. This happens even if
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the website is using SSL and shows a cute little padlock in your browser" [10]
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- Cloudflare tracks you
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Even if your traffic is protected from onlookers, Cloudflare itself can see your traffic[6] because they are a MITM[14][31].
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In addition, if Cloudflare[53] has intercepted your traffic(MITM), so has the NSA[33].
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"If a site uses Cloudflare, then the browser lock icon is a false promise."[14]
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"The short version, a rhetorical question: Would you trust a key escrow regime, in which an “authorized” entity was
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entrusted with the potential to decrypt all communications at will? If not, why would you trust a de facto mass decryption
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chokepoint at which many communications are actually decrypted?"[34]
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In other words,
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- They are in a position to track, tap, and link Internet activity across a wide range of sites. [14]
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- Cloudflare frustrates accessibility efforts[25][27][36]:
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"CAPTCHA remains the most problematic item indicated by respondents"
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Cloudflare is one of the largest, if not the largest source of unconsensual CAPTCHAS, making them quite possibly the
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biggest impediment in accessibility efforts worldwide.
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- Cloudflare makes using Tor frustrating by making efforts to become anonymous more difficult and making it more likely
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that people will use non-Tor connections for some or all of their web browsing. The problem is getting worse with time.
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[13]
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- It's not just Tor[19] but Tor users are the biggest group of people who've noticed it and are organizing against it so
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far.
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- In particular, the model of Project Honeypot depends on one IPv4 address, meaning one person. As IPv4 addresses become
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scarce, more and more ISPs (and whole countries[22]) are forced to use higher and higher levels of NAT. The result is that
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the kinds of treatment of Tor users by Cloudflare starts to be not just for Tor, but for all web users. "Tor is just being
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slightly ahead of what the IPv4 Internet is going to look like pretty soon."
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The next time a large group wakes up, millions of websites might be down (including critical ones) across a whole
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continent. This has actually happened already. [49]
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"It was made clear in the Snowden leaks that GCHQ, the NSA, etc. would like people to stop using Tor so I am sure they are
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very happy to see CF make general web browsing difficult and frustrating for ordinary users." [12]
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- Worse, Cloudflare makes using Tor *dangerous* because enabling JavaScript and images to deal with their system makes it
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likely that some people will enable JavaScript and images on other websites, which, even if Cloudflare wasn't threatening
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them, would. [9]
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- Cloudflare is capable of tracking users of its websites, and initial looks into its JavaScript/CAPTCHA seems to bear out
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that they are doing so.
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- Cloudflare can target individual users with JavaScript malware; since you typically wind up enabling their JavaScript
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to use websites, you fall into their trap. Because they track users, are giving, individualised code, and work directly
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with the US government/DHS, there's no reason why they can't tailor attacks to specific users.
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- Even if they aren't doing it yet, they are at any point one US government administration, one vulture capital funding
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purchase[26], or one internally rogue element away from executing JavaScript code on hundreds of millions of people's
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computers a "highly attractive" target[7] with no oversight. The code CAPTCHA itself protects attempts to detect such
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things from happening.
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- The way that Cloudflare is constructed means that even by accident, billions of people can be analyzed by their
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government[51] and have their access limited or completely cut off at the government's whim.
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*Background : How Cloudflare threatens the web*
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- Cloudflare is a MITM for the whole web
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- As of 3 years ago 10% of the top 25,000 websites used Cloudflare[2]
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- A billion people in china are restricted by the Great Firewall[8]. Anyone who goes so far as to circumvent that must then
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deal with the "Great Cloudwall" for accessing the open internet.
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- This is not just an individual problem, but fundamentally threatens the ecosystem of the web.
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Cloudflare is breaking the open internet one site at a time. The web is massively resilient - we can do without Stack
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Overflow, GNU.org or even Google but when a significant enough portion of websites use a single provider, there starts to
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be a systematic risk that if that single provider goes down, all of the websites behind it will be inaccessible. Worse, you
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won't be allowed to access it unless you have the right kind of US government approved credential, contingent, perhaps, on
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running software only they approve of.
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It is becoming a single point of failure for the internet. [39]
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Right now, there are alternative sources for, for example, the US constitution[17]. It is not unthinkable that Cloudflare
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is getting big enough to threaten even that.
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{FIX ME - make section clearer}
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"A.1 sometimes there are necessary websites for some degree of necessary. Government websites, public service, etc. How
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long until those are behind the "Great Cloudwall"?
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B: Not long. Our service is competitive and convenient. If public service websites choose to use our service for awesome
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DDoS protection, it's their choice."[36]
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- Cloudflare has already started down the slippery slope[52] of censoring websites. If they didn't have a stranglehold on
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people accessing the internet, it would not be a problem. They are big enough that censorship from Cloudflare is starting
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to be a systematic exclusion from the political process.
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"Cloudflare is perfect: it can implement censorship on the fly without anyone getting wise to it!"[40]
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- DNS[39]: given that they have become so systematically powerful, the next step to cementing their power is to attack
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DNS. Their 1.1.1.1 DNS server, like Google's 8.8.8.8, is marketed to people so that Cloudflare will still be able to see
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you're going to them even if you don't interact with websites "protected" by them. It gives them even more data to track you
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with.
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*Background : Where does Cloudflare come from?*
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Cloudflare comes from a project called "Project Honey Pot"[61], originally intended to track online fraud and abuse.
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"What was Project Honey Pot?
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'A service that positions itself as some kind of a grassroot-y anti-spam registry, but in reality seems to be a pro-
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corporate law enforcement tool with the specific aim of entrapping and prosecuting spammers/phishing scammers in a way
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that’s friendly to the marketing industry.'"
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The US Department of Homeland Security approached the developers in 2007-8[1][36] for access to their data and they have
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been working with the US government[54] and law enforcement ever since[1].
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On HTTP GET requests:
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Cloudflare has a history of shutting down open DNS and open NTP servers.
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"It would be great if they allowed GET requests - for example - such requests should not and generally do not modify server
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side content. They do not do this - this breaks the web in so many ways, it is incredible. Using wget with Tor on a website
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hosted by CF is... a disaster. Using Tor Browser with it - much the same. These requests should be idempotent according to
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spec, I believe."
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{FIX ME - "critical of it"?}
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Cloudflare has a history of closing tickets that are critical of it without actually resolving the issue[29][30][32]
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"Cloudflare is based in a country with secret courts, secret police, and secret prisons that are above the law - and this
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secret government has characterized Cloudflare's data as extremely valuable"[28]
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"The CEO says, "Cloudflare's strength lies in the DATA it collects -- not in its CODE.'"[28]
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"The U.S. federal government is a Cloudflare customer."[28]
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"Cloudflare has never stated that a government agency did not install wiretapping equipment or software on the same
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premises as a Cloudflare server."[28]
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"Cloudflare has never indicated that the architecture of its content distribution network is resistant to warrantless
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mass surveillance."[28]
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"Cloudflare has given the Chinese government unprecedented censorship capability."[28]
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"Cloudflare has no intention to shut down as Lavabit did in order to protect the user from unlawful surveillance."[28]
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"Some Cloudflare customers are paying over 1 million dollars per year for an undisclosed service."[28]
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*"But Cloudflare is really necessary, the web is a nasty place"*
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- The more of the web is held within Cloudflare, the more pressure will be on websites not behind Cloudflare
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- As of 2016, by Cloudflare's own data, Tor was not as bad as normal internet connections.
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- People: "But we need Cloudflare to protect us from DDoS.”
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Cloudflare: "That’s a nice site you have there. It would be a shame, such a shame, if anything happened to it. Why don’t
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you let us decrypt all your TLS sessions[59] so we can protect you?"[14]
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*I heard Cloudflare is working with Tor and all is good now?*
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- Just because you can't see the problem doesn't mean it's not there.
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- This is not true. Their websites still CAPTCHA their users, same as ever, and news agencies across the political spectrum
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screwed up stories about how the 'problem is fixed'. [18]
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- It's actually worse, though[17], if we couldn't see it[60] - it was easy to get a lot of riled up Tor users to understand
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that Cloudflare was their adversary. It's a lot harder to convince people who are not blocked from their websites, today,
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why giving systematic control over the world wide web might be a bad thing tomorrow.
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"Right now, Cloudflare says it monitors nearly 1/5 of all Internet visits. An astounding claim for a company most people
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haven’t even heard of"[40]
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- But they are now doing more to track users and threaten the anonymity of Tor users.
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- Cloudflare is one of a couple of large network providers that are capturing the vast majority of digital communications,
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effectively creating private networks the size of the modern internet that are competitive with and not subject to the
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same kinds of scrutiny and regulation as the internet[58].
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*What if we shut down Cloudflare and migrate all websites out of them?*
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We're probably going to have the same problem with another company very soon. Just as when suddenly Microsoft no longer had
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a monopoly on software, we didn't get rid of the problem of proprietary software, there's a couple of problems that, if we
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don't solve them, something like Cloudflare is roughly inevitable as a consequence:
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*Cloudflare DNS*
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"DNS[50] is around, servers are insecure, proper end-to-end crypto isn't the norm hence MITM goes unnoticed, anonymity is an edge case, routing lacks built-in resiliency to disruption, we're always going to have actors building a business model around cobbling together superficial, overapproximating mitigations."[20]
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*Mozilla and Cloudflare*
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"At least for browsing with Firefox, because Mozilla has partnered up with Cloudflare and will resolve the domain names
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from the application itself via a DNS server from Cloudflare based in the United States. Cloudflare will then be able to
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read everyone's DNS requests."
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Sharing DNS requests with Cloudflare represents mozilla having a security hole, straight to the Cloudflare (and probably:
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the NSA).
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*What can you do?*
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Learn more about Cloudflare and make sure the people around you know about Cloudflare. Use Tor by default to be more
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exposed to the blocks. Go to the anti-Cloudflare collaboration repository[41] and make sure websites you use aren't
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"protected", and if they are, contact the people who run the website requesting that they no longer use Cloudflare. Get
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involved!
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References
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[1] crimeflare. Is CloudFlare a honey pot? https://web.archive.org/web/20170721161127/http://www.crimeflare.us/honeypot.html
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[2] ioerror. Issues with corporate censorship and mass surveillance. https://trac.torproject.org/projects/tor/ticket/18361#comment:15
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[3] ioerror. Issues with corporate censorship and mass surveillance. https://trac.torproject.org/projects/tor/ticket/18361#comment:21
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[5] ioerror. Issues with corporate censorship and mass surveillance. https://trac.torproject.org/projects/tor/ticket/18361#comment:28
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[6] ioerror. Issues with corporate censorship and mass surveillance. https://trac.torproject.org/projects/tor/ticket/18361#comment:30
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[7] ioerror. Issues with corporate censorship and mass surveillance. https://trac.torproject.org/projects/tor/ticket/18361#comment:32
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[8] ioerror. Issues with corporate censorship and mass surveillance. https://www.bloomberg.com/quicktake/great-firewall-of-china
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[9] ioerror. Issues with corporate censorship and mass surveillance. https://trac.torproject.org/projects/tor/ticket/18361#comment:51
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[10] crimeflare. Is CloudFlare a honey pot? https://web.archive.org/web/20170721161127/http://www.crimeflare.us/honeypot.html
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[11] ioerror. Issues with corporate censorship and mass surveillance. https://trac.torproject.org/projects/tor/ticket/18361#comment:59
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[12] ioerror. Issues with corporate censorship and mass surveillance. https://trac.torproject.org/projects/tor/ticket/18361#comment:66
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[13] mikeperry. The Trouble with CloudFlare. https://blog.torproject.org/trouble-cloudflare
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[14] nullius. Block Global Active Adversary Cloudflare. https://trac.torproject.org/projects/tor/ticket/24351#comment:8
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[15] Unknown. Google+ https://plus.google.com/105395547687614433866/posts/G9nnQBnLtjp
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[16] Unknown. Google+ https://plus.google.com/105395547687614433866/posts/XnQryQ7hR9G
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[17] msmach. Cloudflare Ends CAPTCHAs For Tor Users https://it.slashdot.org/comments.pl?sid=12641622&cid=57348584
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[18] msmach. Cloudflare Ends CAPTCHAs For Tor Users https://it.slashdot.org/comments.pl?sid=12641622&cid=57388544
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[19] ioerror. Issues with corporate censorship and mass surveillance. https://trac.torproject.org/projects/tor/ticket/18361#comment:90
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[20] ioerror. Issues with corporate censorship and mass surveillance. https://trac.torproject.org/projects/tor/ticket/18361#comment:112
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[21] ioerror. Issues with corporate censorship and mass surveillance. https://trac.torproject.org/projects/tor/ticket/18361#comment:132
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[22] ioerror. Issues with corporate censorship and mass surveillance. https://trac.torproject.org/projects/tor/ticket/18361#comment:141
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[23] ioerror. Issues with corporate censorship and mass surveillance. https://trac.torproject.org/projects/tor/ticket/18361#comment:147
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[24] ioerror. Issues with corporate censorship and mass surveillance. https://trac.torproject.org/projects/tor/ticket/18361#comment:160
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[25] ioerror. Issues with corporate censorship and mass surveillance. https://trac.torproject.org/projects/tor/ticket/18361#comment:175
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[26] ioerror. Issues with corporate censorship and mass surveillance. https://trac.torproject.org/projects/tor/ticket/18361#comment:183
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[27] ioerror. Issues with corporate censorship and mass surveillance. https://trac.torproject.org/projects/tor/ticket/18361#comment:231
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[28] ioerror. Issues with corporate censorship and mass surveillance. https://trac.torproject.org/projects/tor/ticket/18361#comment:236
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[29] ioerror. Issues with corporate censorship and mass surveillance. https://trac.torproject.org/projects/tor/ticket/18361#comment:255
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[30] gk. Cloudflare breaks loading the chat. https://trac.torproject.org/projects/tor/ticket/23141
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[31] nullius. Block Global Active Adversary Cloudflare. https://trac.torproject.org/projects/tor/ticket/24351#comment:20
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[32] nullius. Block Global Active Adversary Cloudflare. https://trac.torproject.org/projects/tor/ticket/24351#comment:44
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[33] nullius. Block Global Active Adversary Cloudflare. https://trac.torproject.org/projects/tor/ticket/24351#comment:52
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[34] nullius. Block Global Active Adversary Cloudflare. https://trac.torproject.org/projects/tor/ticket/24351#comment:60
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[35] nullius. Block Global Active Adversary Cloudflare. https://trac.torproject.org/projects/tor/ticket/24321#comment:13
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[36] Anonymous. Cloudflare philosophy. https://codeberg.org/crimeflare/cloudflare-tor/src/master/cloudflare-philosophy.md
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[37] Peter O'Shaughnessy. Screen Reader User Survey Results #7. https://toot.cafe/@peter/99398584471715976
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[39] ungeich. A new feature in Firefox https://blog.ungleich.ch/en-us/cms/blog/2018/08/04/mozillas-new-dns-resolution-is-dangerous/
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[40] Yasha Levine. iSucker: Big Brother Internet Culture http://exiledonline.com/isucker-big-brother-internet-culture/
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[41] Anonymous. The Great Cloudwall. http://codeberg.org/crimeflare/cloudflare-tor
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[42] lesswrong wiki. Unfriendly artificial intelligence https://wiki.lesswrong.com/wiki/Unfriendly_artificial_intelligence
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[43] Ben Harack. What is an existential risk? https://www.visionofearth.org/future-of-humanity/existential-risks/what-is-an-existential-risk/
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[44] Nick Szabo. Twitter http://twitter.com/nickszabo4
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[45] FSF. Google's Software is Malware https://www.gnu.org/proprietary/malware-google.en.html
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[46] Richard Stallman. Reasons not to use Google https://stallman.org/google.html
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[47] Richard Stallman. The JavaScript Trap https://www.gnu.org/philosophy/javascript-trap.html
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[48] Nick Szabo. Trusted Third Parties are Security Holes. 2001. https://nakamotoinstitute.org/trusted-third-parties
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[49] slashgeek. CloudFlare is ruining the internet (for me) https://www.slashgeek.net/2016/05/17/cloudflare-is-ruining-the-internet-for-me/
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[50] Hamid Sarfraz. How likely is it that CloudFlare is an NSA operation? https://www.quora.com/How-likely-is-it-that-CloudFlare-is-an-NSA-operation/answer/Hamid-Sarfraz
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[51] Karthik Balakrishnan. Airtel is sniffing and censoring CloudFlare’s traffic in India and CloudFlare doesn’t even know it. https://medium.com/@karthikb351/airtel-is-sniffing-and-censoring-cloudflares-traffic-in-india-and-they-don-t-even-know-it-90935f7f6d98
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[52] http://pleroma.oniichanylo2tsi4.onion/notice/1563
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[53] StopMITMInt. Add an option to stop trusting Cloudflare certificate https://github.com/mozilla-mobile/focus-android/issues/1743#issuecomment-351555735
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[54] goody2shoes. Block Global Active Adversary Cloudflare https://lists.torproject.org/pipermail/tor-talk/2018-January/043889.html
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[55] EFF. The Crypto Wars https://www.eff.org/document/crypto-wars
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[56] http://forums.clamwin.com/viewtopic.php?t=4915
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[57] November 2018 Archives by thread http://lists.clamav.net/pipermail/clamav-users/2018-November/thread.html
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[58] https://www.itu.int/en/ITU-T/Workshops-and-Seminars/20181218/Documents/Geoff_Huston_Presentation.pdf
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[59] Thorin-Oakenpants. let's talk about our little buddy cloudflare. https://github.com/ghacksuserjs/ghacks-user.js/issues/310#issuecomment-351913412
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[60] ghost. What do you think about Cloudflare? https://github.com/privacytoolsIO/privacytools.io/issues/374#issuecomment-460413259
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[61] Unspam Technologies, Inc. https://projecthoneypot.org/
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[62] TechRader. Captcha if you can: how you’ve been training AI for years without realising it https://www.techradar.com/news/captcha-if-you-can-how-youve-been-training-ai-for-years-without-realising-it |