Open Whisper Systems (OWS), the group behind the Signal, encrypted messaging app endorsed by Edward Snowden, updated their Android app to circumvent censorship in Cuba and Oman. The circumvention of such Internet blocking is not a new concept—engineers built Tor for the same reasons. Likewise, this is nothing new for OWS either. In Mid-December, they executed a similar method of circumvention for users in Egypt and the United Arab Emirates.
The organization published a blog post titled “Doodles, stickers, and censorship circumvention for Signal Android.” After the stickers and doodles mention, the post described the situation in Egypt and the United Arab Emirates. According to Signal users, OWS explained, Signal’s connection—or lack of connection—decreased the usability to a significant degree. After an investigation, the group discovered that ISPs blocked connections between Signal and the internet.
From the blog post regarding the Egypt and UAE fixes:
“Over the weekend, we heard reports that Signal was not functioning reliably in Egypt or the United Arab Emirates. We investigated with the help of Signal users in those areas and found that several ISPs were blocking communication with the Signal service and our website. It turns out that when some states cannot snoop, they censor.”
This censorship occurred shortly after the Turkish government implemented a 12-hour ban on all social networks—and not even a ban—the government blacked out social media. After the 12-hour blackout had lifted, censorship-monitoring company Turkey Blocks reported and subsequently confirmed that the Turkish government finally put their foot down on Tor users.
From our article on the Tor ban in Turkey:
“Turkey Blocks finds that the Tor direct access mode is now restricted to most internet users throughout the country; Tor usage via bridges including obfs3 and obfs4 remains viable, although we see indications that obfs3 is being downgraded by some service providers with scope for similar on restrictions obfs4. The restrictions are being implemented in tandem with apparent degradation of commercial VPN service traffic.” (TurkeyBlocks)
Open Whisper Systems found that Egypt and the UAE started similarly stopping Signal users. Within a week of the above discovery, OWS began receiving nearly identical reports from users in Cuba and Oman. Per the natural course of events, OWS pushed an app update that bypassed the censorship in both countries. Bruce Schneier, a long-time writer of security oriented affairs, explained the procedure in easily understandable terminology.
“Now when people in Egypt or the United Arab Emirates send a Signal message, it will look identical to something like a Google search,” Moxie Marlinspike explained. “The idea is that using Signal will look like using Google; if you want to block Signal, you will have to block Google.” The technique, known as “domain fronting,” is employed by Tor for the same reasons.
Open Whisper Systems founder Moxie Marlinspike, in essence, explained that for a country to ban Signal; they would have to ban the entire internet as well.
The update already rolled out for Android users; iOS users, assuming the standard pattern applies, should see an update in mid-January.