Signal now offers a feature called “automatic key verification” which complements the existing safety number system. Signal is always end-to-end encrypted, and automatic key verification provides an additional, streamlined way to confirm that there’s no unexpected party between you and the other “end” of an end-to-end encrypted session.
The latest update for Signal Android introduces comprehensive support for linked devices. Now you can easily link another Android phone or Android tablet to your Signal account. Thanks to significant interface improvements to better support large devices, your messages will stay in sync across every screen and look good on all of them too.
We’re also expanding linked device support on iOS so you can link an iPhone to your Signal account in addition to our ongoing support for iPads.
Signal Android v8.20 and Signal iOS v8.22 are rolling out now. Feel free to stop here if that’s all you needed to know, but there’s more info ahead if you want to kill some time while you wait for your freshly unboxed second (or third) device to finish charging.
Whisper Systems was a company focused on the development of mobile security software, which was acquired by Twitter in late 2011. Twitter very generously made some of the Whisper Systems software available under an Open Source license (GPLv3), which has since been under open development by the community. The software has seen a number of new releases based on that open development, and we’ve been calling the project for this continued work “Open Whisper Systems.” Welcome to the project’s new home.
This Spring will be the first Open Whisper Systems Spring Break Of Code, a week-long, expenses-paid retreat to Maui for folks who like software development, security, and the beach. We’ve rented a large beachfront house on the west coast of Maui for everyone to stay in, and will pay for your airfare. While there, you can split your time between island living and working on an Open Whisper Systems-related project that you propose.
RedPhone is our mobile app for end-to-end encrypted voice calls. When we talk about RedPhone, we tend to emphasize the cryptography, and how using it can help keep your communications safe. What we don’t talk about as much is the VoIP application underneath all of that, which it turns out was actually the hard part.
When we were developing RedPhone, we discovered that the cryptographic aspects of it were relatively straightforward. What we didn’t anticipate was how difficult the mechanics of delivering high-quality, low-latency, and highly available voice communication would be.
This describes the basic strategy we developed for the network side of low-latency and highly available calls.
In our previous post, we discussed the global infrastructure that allows RedPhone clients to find low-latency servers when establishing a call. This post discusses the techniques we use to retain call quality when network conditions are less than ideal.
We were excited about our Spring Break Of Code announcement, but the response was better than we anticipated: over 100 extremely impressive proposals from folks around the world who are passionate about pushing the envelope of security and privacy software. After reading all the proposals, we really wish we’d rented a bigger house.
We think the final lineup of accepted proposals is great:
It’s a busy time here at the Open Whisper Systems factory, and we need all the floor space we can get. We still have some first-edition T-Shirts that are taking up some space, so we’re offering them to you for the cost of shipping and handling.
There are two designs available in a number of sizes:
Spring Break Of Code, Day One.
One of the first times I met up with Moxie while travelling, we met at a dive bar in San Francisco’s Mission District, packed with hipsters. I had nineteen years, a modified state ID card, and just hitchhiked into town. We sat at the bar, and both ordered well gin and tonics.
I had a proposal, the sort of get-rich-quick scheme it seems that only 18th century pirates and lazy hacker-squatters are capable of contriving: We fly to China. Then, we spend a few grand purchasing a Chinese junk rig, and equip it with a system of pulleys so that we can man the sails from the cockpit, solo if necessary. Next, we fill the cabin with about as much potable water as we can carry and enough dried food to stave off starvation, and set a course across the northern arc of the Pacific – avoiding the treachery of the South Seas – for San Francisco. The choice of vessel was key, the battened sails and flattened hull of a Chinese junk rig make it arguably one of the safest ships to make a transoceanic voyage alone, not to mention the financial incentives: being rare in the Americas, a well-kept junk rig would go for anywhere from $50,000 to $250,000 USD – not to mention grant you free slip fees at just about any marina from Anchorage to Punta Arenas. How could anyone turn down such a preposterous plot which included adventure on the high seas, a high mortality risk, riches and notoriety?
Spring Break Of Code, Day Two
“I am torn on how best to introduce myself out of context like this, the idea of rattling off facts from my resume is my first instinct, but that seems terribly conventional. With the goal of introducing myself and the entirety of my character, my second (highly unconventional) instinct is to link you to my online dating profile with the prayer that such an action would be taken in the desired context. Through my indecision I hope to explain who I am and why I would like to travel across the country to be involved with the Institute for Disruptive Studies. So here goes…”
Spring Break Of Code, Day Three
I am no stranger to Hawaii. Although I’ve never lived here myself, I’ve visited the islands perhaps a dozen times. My grandmother and my father were born and raised here. My mother attended college here. I have aunts, uncles, and cousins who’ve lived on various islands, moved away, came back, moved away and back again. I even have Native Hawaiian blood in my veins.
But this trip is different. This time it’s not about family or heritage. This time, I have a mission: to make secure text messaging and calling easier, more accessible, and more prevalent.
Spring Break Of Code, Day Four
The main sound on top of the ocean is the click clack of laptop keys, and the jangle of test calls and SMSes. A neighbor stopped by to comment that we must be the next Facebook, the next Google; working instead of surfing made sense in his mind only in the land of money at the end of the tunnel. He loaned us his stand up paddle boards, surely expecting a return on investment 10 fold down the line when we exited into the sunset. A journalist visiting Open Whisper Systems’ Spring Break of Code commented that she expected more philosophy, politics, and conversation. After all this group is composed of people who are not only technologists, but also open source evangelists, activists, and humanists. Lilia went over some of the why, but practically anyone could see we were concentrating on the how, and in the frenzied silence it was clear that a common philosophy was assumed and what bound us here was the challenges in the technology to power that philosophy.
Spring Break Of Code, Day Five
I know very well that each and every crisis of modernity is concentrating, concatenating, and seating more deeply into everyday life. I know the struggles of the world’s unseen and unheard are being subsumed – appropriated – under and into the framework of a liberal democracy, leaving those at the periphery still under the yoke of capital. The Right further entrenches itself into political discourse, both in the United States, and (more extremely) abroad (Finland, Greece, … et al.). The Left is no less problematic: reiterating the petty values of social democracy, negotiating the terms of our entrapment within capitalism. Every season, new horrors fall from the clouds and rise from the seas as industrial civilization demonstrates that terraforming can also work in reverse. The world’s genetic library – the most prime commons, if ever one existed – is rapidly contracting via extinction, privatization, and engineering. The colossal failure of ideology in the twentieth century has left the radicals of today no other choice but to see themselves as “post-ideological”. This is a deeply concerning conundrum, as ideology survives in post-ideology, different only to the extent that it is less apparent. Yes, it seems like we are living in end times – an entire era of Apocalypse – made only more insidious by our optimism in its shadow.
Spring Break Of Code, Day Six
Because secure systems aren’t valuable if they’re not used, Whisper Systems has always focused on delivering strong cryptography alongside a great user experience. That’s the reason call quality has always been a priority in RedPhone’s development.
We know that, for many users, RedPhone has consistently delivered a call quality experience comparable to commercial mobile VoIP solutions. But we also hear from users who report problems like dropped calls, distracting levels of echo and latency, or inaudibly low in-call volume. While we investigate these reports and attempt to resolve them, we don’t have a clear view of what situations cause RedPhone’s call quality to degrade, or how to prioritize our development efforts.
The last code committed, the final waves surfed in to the shore, the closing sunset of Spring Break Of Code.
Open Whisper Systems is a project focused on developing Open Source security and privacy apps for the mobile environment. With all of the recent discussion about PRISM, Boundless Informant, and FISA orders, there has been a surge of new users and inquiries about how to get involved.
At Open Whisper Systems we help develop TextSecure, an encrypted chat application for Android. TextSecure was designed as a general purpose SMS/MMS client which would also automatically encrypt conversations when communicating with other TextSecure users. For those encrypted sessions, TextSecure uses a compact derivative of the well-known OTR protocol.
We’re currently in the process of transitioning TextSecure to use a device’s data channel as a transport for communication with other TextSecure users whenever possible. This enables communication with the upcoming TextSecure for iOS, helps users avoid SMS fees, and obscures conversation metadata from telcos.
The transition to a new transport is also a good opportunity for us to evaluate and introduce additional cryptographic protocol changes. Below is one cryptographic protocol change we’re thinking of making that we’d welcome feedback on.
Traditionally, asynchronous messaging systems such as email have relied on protocols like PGP or S/MIME for cryptographic security. These protocols work the way most people are familiar with: one who wishes to receive encrypted email advertises a public key, and those wishing to send encrypted email to that person encrypt their outgoing message with that public key.
From October 11th to October 13th, we’ll be hosting an informal Open Whisper Systems Alpine Hackathon for those in or around Zurich, Switzerland who would like to contribute to Open Whisper Systems-related projects in a collaborative setting with other co-conspirators.
My cell phone used to be a black and white Nokia until a couple of weeks ago when I decided to enter in the smartphone world. Now that there are more mobile devices connected to the internet than computers, I think it’s time for me as well to discover the possibilities of this technology. During this few weeks I’ve been playing with my new toy, checking how to secure it, and seeing what free software is around to use cryptography on it.
At Open Whisper Systems, we’re focused on creating easy-to-use privacy-enhancing technology. Our projects are free, Open Source, and tend to be oriented around the mobile environment. We’ve been working on apps like TextSecure and RedPhone (which provide secure text messages and secure phone calls) for years now, because we believe that it’s possible to develop well-designed secure communication tools that are both privacy-preserving and a joy to use.
This winter, we’d like to invite you to join us for “Winter Break Of Code,” a week-long free trip to Kauai for anyone who’d like to spend a week working on this type of easy-to-use privacy-enhancing technology in a collaborative environment. We’ve rented a large beachfront house on the north coast of Kauai for everyone to stay in, and we’ll pay for your airfare. While there, you can split your time between island living and working on an Open Whisper Systems-related privacy project that you propose.
At Open Whisper Systems, we’ve been working on improving our encrypted asynchronous chat protocol for TextSecure. The TextSecure protocol was originally a derivative of OTR, with minor changes to accommodate it for transports with constraints like SMS or Push. Some of the recent changes we’ve made include simplifying and improving OTR’s deniability, as well as creating a key exchange mechanism for asynchronous transports. Our most recent change incorporates what we believe to be substantial improvements to OTR’s forward secrecy “ratchet.”
At Open Whisper Systems, we’re working to both advance the state of the art for secure communication and also reduce the friction required for ordinary people to make use of it. We want everyone to have access to advanced secure communication methods that are as easy and reliable to use as making a normal phone call or sending a normal text message.
With these goals in mind, we’ve been working with CyanogenMod over the past few months. CyanogenMod is an open source aftermarket Android firmware distribution with ten million users and ~20k installs a day. Their rapid growth is beginning to rival Microsoft for the third-largest smartphone OS distribution.
As of today, the TextSecure protocol will begin shipping as part of the CyanogenMod OS-level SMS provider, in an effort to provide completely transparent end-to-end text message encryption between all of their users.
After our wonderful experience with Spring Break Of Code, we were excited to try this again. Even with high expectations based on our experience in the Spring, the response was still better than what we could have hoped for. The hundreds of high-quality proposals we received were really inspiring, and we hope that one day we can get a space large enough for all of the amazing people who are passionate about the development of privacy-enhancing technology.
We think the final lineup of those attending in January is going to be great:
At Open Whisper Systems, we often get emails from people who’d like to donate money to the project. For an OSS project, particularly one that aspires to a collective sense of ownership, handling donations is not always entirely straightforward.
The fundamental contradiction is that while donations are meant for a project, they’re traditionally sent to a person. Even if a project sets up a bank account, there are still only a few people who have access to the money itself, and distributing it appropriately can be hard to figure out.
It’s never been clear to us how we should handle small donations, so oftentimes when people ask about donating, we just tell them that the best way to help is to use the software, spread the word, and file well-documented bugs when they find them. Which is true! But it’d also be great if we had a nice system for handling donations that matched our objectives for collective ownership.
Building a social network is not easy. Social networks have value proportional to their size, so participants aren’t motivated to join new social networks which aren’t already large. It’s a paradox where if people haven’t already joined, people aren’t motivated to join.
The trouble is that while building a social network is hard, most interesting software today is acutely “social.” Even privacy-enhancing technology, which seems anathema to the aesthetic of social networking, is tremendously social. For people to effectively use private communication software like TextSecure, they need to be able to know how to contact their friends using TextSecure.
Winter Break of Code, Day One
The Winter Break of Code, being closely linked by name to the season of Winter, began with a calm trickle of ex{hausted,cited} people carrying laptops and cell phone collections after a parade of delays and weather issues. Off the plane after a pitch-black descent, the humid fresh smell distinct to this place along with my feet landing on soil was a good hint that we were indeed on an island and this was actually happening. It was very welcome.
Winter Break of Code, Day Two
By all rights, I should not be here. My application was last-minute to say the least, and little more than a casual note that I’d be down to reprise my role from SBoC as web hacker for whispersystems.org. Maybe it was because of my work in the previous months on tweaking the site layout to be responsive, or because @bcrypt (who is infinitely more qualified) was too dedicated to her work at the EFF to take the time off, or because my birthday happened to fall on this week, but for one reason or another, the universe smiled, and here I am.
Winter Break of Code, Day Three
We are at the halfway point of Winter Break of Code. We have two homes near the beach shared by 12 people. 10 of us are working on the apps & website and 2 are leading up delicious dinner efforts. We’ve spent time on the beach, in the ocean, in the mountains, and of course working. Concepts for future startups and tactics about self-publishing books are brewing, and conversations are lined with politics and activism. Work sessions are focused on making cryptography usable in existing Android apps and soon-to-be-released iPhone apps.
Winter Break of Code, Day Four
At the Open Whisper Systems spring break of code in 2013, I started work on TextSecure iOS. People are chomping at the bit to use our software on iOS. After a hiatus from the project, I’ve been happy to return to it over the last few months, joining some other contributors, including Frederic Jacobs as co-lead, Alban Diquet, and Claudiu-Vlad Ursache submitting pull requests, even over the holidays, with important cryptographic storage and UI-polishing contributions, and Bitcoin donations coming in from around the world.
Contribute code or coins.
Winter Break of Code, Day Five
If commodities could speak, they would say this: our use-value may interest men [sic], but it does not belong to us as objects. What does belong to us as objects, however, is our value. Our own intercourse as commodities proves it. We relate to each other merely as exchange-values.
– Marx, Capital: A Critique of Political Economy, Vol 1.
Marx saw modernity more acutely than most of his contemporaries, and provided a description of capitalism that remains, in my opinion, quite useful.
However, we must be brave enough to attempt to understand his description of the relationship between commodity and value in the context of a world very different from Industrial Revolution-era Europe. That is, one which includes the strange new primordial soup of the internet and capital.
Imagine, as Marx expects of us in the passage above, that an “internet” commodity could speak. What would it say?
Winter Break of Code, Day Six
A lot of great memories will stay with me after this intense week. The house surrounded by palm trees, people with computers in every corner, laying down on a sofa, chatting on the balcony, and sitting down on the carpet. The surf and hiking breaks on this astonishing Kauai’s landscape, sharp mountains covered by forests falling into beaches of fine sand and fun waves. The nights spiced with Moxie’s tasty cocktails and long deep conversations about the meaning of life, the internet and everything.
Winter Break of Code, Day Seven
Spring Break of Code 2013 I cut open my foot and hand while surfing; both wounds easily warranted stitches. Winter Break of Code 2014 I banged the top of my foot surfing over some coral; the cuts were sealed within minutes. Spring Break of Code 2013 I struggled with the Android SDK, while Winter Break of Code 2014 I caught myself taking a few too many short-cuts. On day zero nothing is easy, but over time you improve, spilling a little less blood every time.
Today’s release of TextSecure is the final step in the transition from a private SMS app to a private asynchronous IM app that does not depend on SMS/MMS.
Using the lessons we’ve learned from the SMS environment over the past four years, we’ve developed an open protocol for asynchronous chat that enables private communication instantly with friends, private groups for real-time collaboration, and the ability to quickly and seamlessly share media privately – all without depending on SMS.
One of the major features we introduced in the TextSecure v2 release was private group chat. We believe that group chat is an important feature for encrypted communications projects, so we wanted to try to summarize some of the existing work in this area, as well as how TextSecure’s group chat protocol functions.
At Open Whisper Systems, we want everyone to have access to advanced secure communication tools that are as easy and reliable to use as making a normal phone call or sending a normal text message.
Over the past year, we’ve been working to bring the privacy software we’ve developed for Android to the iPhone, and today we’re releasing Signal – free, worldwide, encrypted voice calls for iPhone, and fully compatible with RedPhone for Android.
This January, Open Whisper Systems will be hosting a Winter Break Of Code. We’ve managed to get access to a large beachfront house in Kauai for three weeks, and we’re inviting people to join us. If you’re interested in spending one to three weeks in Hawaii working collaboratively on an Open Source project to make private communication simple, we’ll take care of your airfare and housing so that you can be there.
Winter Break Of Code is an opportunity for designers, developers, writers, strategists, and creative thinkers interested in privacy and security to spend some time contributing to privacy-related projects in a retreat-like setting with other co-conspirators. Think of it as an extended hackathon, but with your travel expenses paid, and with breaks for surfing, hiking, swimming, and just generally being in Kauai.
Everything that Open Whisper Systems produces is free and Open Source. We’ve been working on apps like Signal, TextSecure, RedPhone, and Flock for years now, because we believe that it’s possible to develop well-designed apps that are both privacy-preserving and a joy to use.
At Open Whisper Systems, our goal is to make private communication simple. For the past three years, we’ve been developing a modern, open source, strong encryption protocol for asynchronous messaging systems, designed to make seamless end-to-end encrypted messaging possible.
Today we’re excited to publicly announce a partnership with WhatsApp, the most popular messaging app in the world, to incorporate the TextSecure protocol into their clients and provide end-to-end encryption for their users by default.
Every year when we do this kind of call for proposals, our experience from past events sets our expectations higher. Even with really high expectations this time around, we were blown away by the number of high-quality proposals we received for this winter. It’s inspiring to know how many people are thinking seriously about the development of privacy-enhancing technology, and we hope that one day we’ll have a space large enough to accept all the proposals that we wish we could.
The lineup for this January is set to be really great:
Winter Break Of Code Day 1
I woke up this morning feeling like this routine was normal, instead of implausible. Two days ago, I was in New York City, riding the train with millions of other commuters in the freezing snow. Today, I went surfing on a beach in beautiful Kauai. In the same absurd fashion, I shared meals, stories, and workspaces with people, who days earlier, I had only read about and admired from afar. The promises of the Winter Break of Code seem impossible: a vacation in paradise, large milestones of work to be met, a welcoming space with talented companions. But when Moxie came into the bedroom this morning strumming his ukulele to wake us for the daily morning stand-up, up we were, ready to claim the small victories in the browser extension project, the Signal iOS client, and the Android applications from the day prior and to lay out plans to further the state of user-friendly secure communication tools.
Winter Break Of Code Day 2
Because I might get sappy, here’s a picture to ease that before I let it all out.
After being promptly woken up by numerous roosters at 7:30 AM, I still can’t believe I’m here. My application was pretty last-minute, completed when I was in a state of droopiness and scholarship-application-hyperdrive. But I got on a plane from the Midwest, went from cloudy, 20 degrees with windchill making it feel like 0 to sunny, 77 degrees with mild winds making it feel still 77 degrees.
Winter Break Of Code Day 3
As it does every morning, the day started with Moxie singing the stand-up song, reminding us all (and waking up the slackers) that at 9am sharp we all get in a circle to discuss what we accomplished the day before and what our priorities are for the coming day.
Winter Break Of Code Day 4
I’m not sure those attending their first break of code know what they are getting into. When I said “sure” to Moxie my first break, I sure didn’t. During that week I had already come to the conclusion “I have to see this (TextSecure iOS) through”. In the intervening time, I’ve become an expert on the Axolotl protocol, come to understand ZRTP, picked up the world’s best collaborator, helped with the final polish of Signal with RedPhone support and contributed a lot of code to the TextSecure prototype.
Winter Break Of Code, Day 5
The prophetic discourse of the Karai can be summed up in an observation and a promise: on the one hand, they constantly affirmed the fundamentally evil character of the world, on the other, they insisted that conquest of a good world was possible. “The world is evil! The world is ugly!” they said. “Let us abandon it!” they concluded. […] In short, it was not the discourse of the prophets that was unhealthy, but indeed, the world in which they spoke, the society in which they lived.
– Archeology of Violence, Pierre Clastres
At the peak of the Soviet Union’s civic society, more than five-hundred thousand Soviets belonged to a complex, almost ecological system of bureaucracy known as the Nomenklatura. Itself a reference to the Roman ‘list of names’ – a codified taxonomy into which people could be organized and signified – the Soviet government was built and constrained through social proximity.
The initial idea was to institute a horizontal decision-making system. A methodology that could define and populate thousands of roles for the collaborative administration of social order: ministers of industry, pedagogy, natural resources, foreign relations, internal affairs, communications, and so on.
It was a form of governance intended to gradually flatten a hierarchy that the early industrial revolution had exaggerated. However, over time the mechanics revealed – somewhat conversely – a total institutionalization of ‘nepotism’. Certain senior members of the Nomenklatura had the privilege to appoint new members, and maintain long lists of qualified candidates. New members, now obliged from a favor, formed allegiances to their patrons. Patrons themselves carried social debts to those who appointed them, and it went on like this up the stack into the inner circle. The hierarchy didn’t flatten, it sharpened.
Speed ahead to our modern life. My social relations are all but completely virtualized. My list of friends and followers, contacts and matches, profiles and handles … all thrum wildly. Apps are released every week which impose and constrain my lists into new formations, reconstructing my social life over and over. It’s possible to see the reflection of Soviet governance in our own lives today; perhaps there are hundreds of thousands of members (less, probably) of a new bureaucratic class – technocratic knowledge workers, let’s say – who organize and signify civic life in the contemporary age. Building cooperative protocols and APIs and apps and networks. Designing the interfaces and behaviors and experiences of everyone else. Teaching but sometimes refusing to learn, giving generously but sometimes taking without permission, anticipating what we want but often supposing what we want without asking. Designing our dismal fate. Slowly appointing their heirs by proximity.
As a publisher and designer, I count myself among this degenerate few and tread carefully whenever I manage to move or speak at all.
Winter Break Of Code, Day 6
I’ve been working with Open Whisper Systems on TextSecure for about a year and a half. I feel like I’ve earned better treatment than being forced to blog at knifepoint, but here we are, so I’ll tell my story.
Winter Break Of Code Day 7
Yesterday was a day of meetings. Discussion and debate flourished. Conversations ranged over all parts of every project. Words spoken aloud may have outnumbered lines of code shipped. The entire team was fully engaged and people nearly had to be dragged out of the house for an afternoon hike to the top of the ridge.
Despite our intense collective focus on conceptual progress, when Trevor agreed to present an overview of elliptic curve cryptography, the entire team, veterans and “li’l Whisperers” alike, fell silent and gathered ‘round the whiteboard.
We learned about fields and curves and groups, of basepoints and cofactors, secrets and signatures. Questions abounded and Trevor delivered the answers, one after another, albeit with enough handwaving that I thought he might lift off and fly himself back to the mainland. However, there was one question that even he could not answer: Why are they called elliptic curves?
From Weierstrass to Montgomery to Edwards formats, these geometric objects that form the essential mathematical underpinnings of many modern crypto systems are not defined by ellipses, nor do they resemble ellipses. Not even for very stretchy definitions of an ellipse. There is no immediately obvious connection. So why do we call them that?
As usual, to understand the universe, we must first bake an apple pie from scratch. Or at least pretend to.
Winter Break Of Code Day 8
A few weeks ago, an email full of information to help prep for Winter Break of Code popped up in my inbox. Throughout my personal countdown to the day I got to leave San Francisco for Hawaii, one line from that email continuously resonated throughout my mind: “Have your development environment ready to go.”
Winter Break Of Code Day 9
Today we hiked the Kalalau Trail and swam beneath the cold spray of a waterfall.
Today we discussed the finer points of the axolotl protocol used by TextSecure.
Today we delighted in “shave ice”, a local delicacy that is definitely not a snow cone.
Today we wrote copy, polished features, closed bugs, and merged pull requests.
Measured by lines of code, today was short. Measured by steps taken, it was tall. Measured by ideas discussed, things learned, and sights seen, it was towering.
