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Yeah, we're here to listen again,
one of the big problems of today is
how to communicate with
one of those gumshoe people sniffing out
behind you, including
picking up your meta data from the
commercial side of
whatever the system is.
And this is another try if I write,
if I rightly inform, this is the
problem is with most of the stuff you
still you either have to
be linked to some GSM
number or you have to have
a WiFi around.
You need some IP connection.
And obviously people have been thinking
about that.
And.
This is Tostan, his full name is
Tostan Growth.
Excuse me, I'm pronouncing it the German
way and
he's part of the.
Prior team since two years,
he's originally from Germany, is a
free software activist on.
Programmer and he lives in Brazil.
Envy,
where's your tan, by the way?
OK, so
let's have a big hand for to go to who's
going to present prior to you.
Thank you very much all for coming here
today, for taking time out of your busy
schedule. I hope you had a great Congress
so far.
And thanks for coming to hear about
Brierre, so let's get right into it.
What is Brayer?
Essentially, Brierre is a communication
tool. You could say it is
been developed, being developed since
2012.
So quite some time.
And some of you might be thinking now
of yet another messenger,
like, don't we have too many of those
already? And I totally agree like
that. Who have you have at least five
messages on your phone that you use to
connect to people?
Yeah, it's crazy. Like, I think it's
a third of the audience who has that.
So I can only recommend
everybody don't build yet another secure
messenger unless
it's substantially different from all the
others that we have so far.
And to motivate a little
bit why we need yet another one,
let's look at some of the threats
that people who use messengers
are facing.
Yes. Before we got into this, sorry, I
forgot the slide brier's focus
on security and resilience.
And I think especially this resilience
part is something new.
And we're hearing the resilience track of
the chaos communication Congress.
So this will be important as
well. So now back to the threats
we are facing when we use communication
over the Internet
for classical warrantless eavesdropping.
Like, they'll read our messages, but
we want confidentiality
and eavesdropping
has been largely solved
by end to end, encryption
essentially means at the source of the
communication, the message is encrypted
and that the destination, it's decrypted
and nobody in between, not even any
servers on the way can read the content.
That's great. And there have been some
awesome advances in the last year
that made into an encryption usable for
everybody.
So you don't see any keys anymore.
You don't need to sign anything.
It just works. It gets out of your way
and this is the way it should be.
The only problem of end to end encryption
is that it still needs more adoption.
And I'm especially looking at you, ello,
Facebook Messenger and Telegram
where end to end encryption is available
but not activated by default.
And that's something that I hope will
change in the future as well.
Next problem, metadata.
You're here at the Congress.
You probably know all about it.
So I will be brief.
Metadata is data that is
not the content itself, but everything
else like of the time of your
communication, who you are communicating
with and how much.
And that is
almost all that your adversaries
need to know about you, because it tells
a lot and you can deduce a lot of
information from it.
And this problem
has been largely ignored.
Unfortunately, there
is just a few projects to try
to address that, but it's a very
important one.
And if you don't believe me
that it's important, maybe you
will believe this guy.
Yeah, first of all,
we have no audio.
Mutual friends to go back.
Yeah, four old personal
description of.
Can be mitigated by
a mutual friend, Stewart Baker is
absolutely correct that we
kill people based on their data.
But that's not what we do with this
metadata,
thankfully.
Well, I was working up a sweat there for
a second.
So for those who might not have
understood it, he said, we kill people
based on metadata alone.
And he was talking about these two kinds
of metadata and he was
talking about phone records mostly, and
domestic ones and foreign ones.
So he's basically promising, oh, we don't
kill the Americans based on the metadata,
just everybody else.
So these phone records,
especially when it comes to messengers,
are a nice selecter
and they are all centrally stored.
And your entire address book is uploaded
to to people's servers
and then the servers and all of the
metadata that's going on.
And it's juicy target for an attack.
Like if you compromise this kind of
infrastructure, you know, you have all
the metadata of all the people
communicating for the service,
but also timing a text
are quite easy.
So using phone numbers
is maybe not the best idea,
but apart from eavesdropping and
metadata, there is
also censorship and
service blocking.
So basically they block our stuff
and we want to have it accessible.
This is just one example here from China
where it happens from time to time.
And of course, I know we can
usually circumvent stuff like there are
tools, but this is for technical elite.
This is not for the big masses that can
just easily circumvent these blocking and
censorship.
And it happens all over the world, I
don't know how much you're following
this, this happens in Turkey.
In Brazil, the courts are very happy
to block what said once in a while, even
though it's used by almost everybody for
for lots of important things.
And that
shouldn't be possible, right?
This is even worse,
like even in industrial
countries like Germany or the United
States, politicians are seriously
discussing to
turn off the Internet completely.
And this is really bad, like they
they turn, they pull the plug and we lose
all access and that
can happen. But thankfully,
I think politicians understood that we
rely economically a lot on the Internet.
So turning it off is also a bad idea
for other reasons.
But in many countries like Cameroon,
for example, where they have this bring
back our Internet campaign,
it's still a suppression instrument by
the governments because the reliance
on Internet is still relatively small.
So so people don't start the revolution.
Then the Internet goes down
in India. There have been 69
total shutdowns since 2010
in various provinces, mostly in the
north.
And there's many other examples, but I
won't show you all of them,
so this is when the government is pulling
the plug and disconnecting us all.
But it could also happen that
there is a natural catorce catastrophe.
Infrastructure breaks down.
Maybe there's not even electricity.
The uplinks don't work anymore.
And we are in a big mess and still need
to coordinate help.
You still need to communicate, still need
to find people.
Another likely scenario that could happen
where Internet won't be
available is
the zombie apocalypse.
So if your tool doesn't work while
there's a zombie apocalypse happening,
then maybe your tool is not as good after
all.
So now let's look a
little bit more detail into Brayer and
how Brayer is attempting
to address these issues.
It's just it's still a work in
progress. It's see it as
a research approach of addressing these
problems and.
The the main difference
is that Brayer is
not using
a server
to relay old people's
communication.
Now, this is how all of these
messages you have on your phone work.
There is a central server infrastructure.
Whenever you send a message, it goes
through there and they know who
you are and who you talk to.
And if you cannot reach the server,
you're out of luck. You cannot send
anything.
So that's why Brayer removes the server
out of the equation and
connects people directly, peer
to peer.
So the great thing about this is when you
don't need to reach a server anymore,
then you can use what you already have in
your pocket anyway to make connections
to people. And in our case, with our
smartphones today, this is the
Bluetooth radio and the Wi-Fi antenna
you have in your phone.
So.
People can find each other
for Bluetooth. People can find each other
in local lands and white and Wi-Fi
networks, and then they can directly
make connections.
And this is only good for
short range, unfortunately, because our
phones are designed like that.
But it still is good if you
live in a densely populated area where
a lot of people and the social network is
strong.
So they're the short range doesn't matter
so much.
But Brayer has been made in a way
that the way that data
can be transported through
whatever means, like as long
as you have like a simplex or a duplex
datastream, you can send your fine.
At the moment we don't have these, but
you could easily imagine to vry, just to
plug in, to put it into
Brayer.
And then you can enhance your phone
with one of these, like you can have a
satellite uplink.
Or if somebody knows
ham radio, you can use
this with your phone as well, or other
devices and extend the
range and then communicate over
longer distances.
And yes,
you can even use carrier pigeons, it's
only partly a joke,
so sneaker networks just
put your data on the flash drive,
attach it to a carrier pigeon, put it in
the mail, send it to your friends.
They put it in and they receive the
messages end to end.
Encrypted, of course.
So.
Like I said, views end to end encryption
with this authenticated stream cipher
there with 256 bit keys.
We support forward secrecy as well,
of course, but there's a catch
since data can be transported also
through carrier pigeons or whatever means
you come up with.
There can be long delays for messages to
arrive so you cannot roll kids forward
so, so frequently.
So each transport has a key
rotation period
that it uses to establish forward
secrecy.
And when we have transports
that have like a very low latency,
we can also use ratcheting.
But this is still something we need to
implement, unfortunately.
So but but when you use this kind
of encryption, you somehow need to
exchange a shared secret that you
use to encrypt your messages.
And Breyer does this
by forcing you to actually
meet with the person you want to talk
to.
And we do this because this
is the only way we know of
that you can use to prevent men in the
middle of text, like into an encryption
is great. But if you have a man in the
middle and you don't know it,
end to end encryption doesn't help you.
And that's why the the other existing
messages like signal a WhatsApp, allow
you to verify the safety numbers after
adding people like Brierre puts his
first.
There is one thing, though, because
people don't like to meet up or cannot
meet up, so we introduce the possibility
to allow a trusted peer to introduce
two of their contacts to each other
and then they make a direct connection.
So they run a different Helmond
connections through the person.
And only when both accepted the
invitation and acknowledged that they
deleted the keys to establish
forward secrecy.
Then they start making direct connections
to each other and they are connected in
this Peer-to-peer network.
So Bryar only connects to your direct
peers. It does not use a distributed
hash table or something like this.
This is because we want to be able to run
this on our mobile phones and everybody's
concerned about battery usage and
distributed hash table is basically
like a big chatterer going on.
Everybody is talking all the time for
everybody. And this is burning your
battery because you're sending data even
when you're not using it.
So that's why we connect only to direct
Peerce.
Let me advance to the next slide, because
then you have something to read.
These are the cryptographic algorithms,
views, and you
see there's one on the left side, an
arrow to the right side.
This is what we are migrating to at the
moment. So we're migrating from Blak to
as a make function to black
to be.
And similarly, from this brain to
curve's, we are migrating to the
Edwards curve down there.
So what can I has Internet as well,
because I was talking only about this
Bluetooth and Wi-Fi stuff, but you're not
always in close range and you don't
always have your ham radio connected,
right.
So we here at least
we have Internet most of the time and we
want to be able to use it. And so, yes,
you can have Internet.
And how we do this is we use Tor.
So Toure is integrated into Brayer
when you install it on your phone.
You don't need another app,
you just start
the app and Tau is booting
up without you knowing about it.
And it starts a hidden service
on your phone.
Like, I assume that most of you know
what a hidden service is.
But for those who don't, let me
give just a brief introduction.
So there's this purple cloud
is just an abstract way
of viewing the network at work.
And there
are Alice and Bob, and they both have a
hidden service on their phone.
So they have a connection into the one at
work.
And each of them are basically picking
three tor relays
and then they find a rendezvous point in
the middle and they establish
the connection for this.
So they never make a
direct TCP IP connection because
this would leak metadata directly to any
network observer. So you would if you
if you look at l'Est traffic, you would
see the connection to Bob.
But in this case, you just see this
connection going into the network and you
have a hard time following where it comes
out.
I have to admit, though, the tour is not
perfect, like if you have seen
yesterday's talk, they say it was good,
but it's not alone. There's other
solutions, but they are not perfect.
And there is no anonymity
system at the moment that can resist
a global passive network observer,
which probably the five eyes
can do. So if they can see all network
traffic, they might be able to
anonymize some of the connections,
unfortunately.
But we can work on this.
Like I said, Breyer is agnostic
to the way data is transported.
So you can just write a data transfer,
plug in, put it in when the
next best thing comes and just all
migrate to that without losing
your contacts or any or any of your data
is just another way to transport data.
You can also use all at the same time if
you want.
So we don't have too much time
to go into into detail, but let
me explain how Brierre works at a little
lower level.
So essentially it's simple.
You have groups or channels
like water pipe, like, you know, the
Internet is just a series of pipes
and you have messages.
And these can be can be anything you
want. You can put your own data in there.
In our case, we have like some binary
data format that we use and we.
We open for any purpose we need, we open
the dedicated channel, so if you have
private messaging, you just open
a group between two people that only
these people exchange messages through.
But you can expand on that.
And you can also create groups that where
people like in this case,
they share messages with other people.
And then you can also share this group
with all your other friends.
And this is what we call forums.
In the forum, everybody can read and
write messages and everybody can share
this forum with other people
in the private message context, you
cannot share that. You cannot share your
private conversation with anybody else.
It's just between you and your peer.
And now let's look at this sharing
graph, so imagine you have this this
forum group,
which are essentially the pipes
and then you share it with your friends.
Then every edge on this graph
is the sharing relationship and
the notes are the peers.
And the green ones are the
ones that are online at the moment.
So so if these people write messages in
the forum, they can have conversations
and they only exists on people's phones,
there is no service where they can get
uploaded to.
So there's also no single proof of what
is the current state of the discussion,
because the people that are offline,
they only get messages when they're
online, but they only get them when they
have a connection to people who have the
messages. So if these people have
messages they flow through here
or if on the other end they get them
right away. But this unfortunate fellow
here on the bottom, he's out of
luck because he won't get the messages
that that are being sent here
unless these people or some people
along the sharing graph come online.
So similarly, like when the
connecting point and the top goes offline
and these people keep chatting, these
people won't read the messages.
And this is a tricky opens onto
tricky new problems like
what happens when you suddenly get lots
of messages, how the traditional
messaging service do that.
They have a linera history.
And suddenly if you get two day old
messages at the top, that you are very
confused. So that's why we use
a threaded conversation structure
where people can can reply to each other
in branches and later you can merge these
branches back together to have a
continuous and consistent message history
where you can also find stuff again.
So this is a very simplified
view of the architecture of Brayer.
You see in the bottom, the blue box
is called what's called Brembo, and this
is released as a separate library.
It gives you the the peerce,
the cryptographically the database to
store stuff. And the message
synchronization through these various
data transports the gray boxes we have
not yet implemented, but plan to do so.
So he Lamplugh to talk maybe
later, HPN Wi-Fi direct.
And then on top of this Brembo library,
we have to Brayer Core Library,
which gives you all the features that are
just built on top.
Like the message you have, messaging
forums, blogs, groups and an RSS
import into the blogs, this
is like also for for censorship
circumvention. When you have friends on
Brayer that
share blog shares as ft content
with you, because you cannot access that
wherever you live, maybe like BBC News in
China or something.
And then on the top, we have the actual
applications that make use of the
libraries.
So at the moment we have an Android app
and we plan to have a desktop program.
And we structure this this way in
libraries so you can build your
own peer to peer things with this
technology without starting from scratch,
so please go and decentralize
all the things.
And I'm really serious here
when when I started out
like advocating for decentralization, I
was always thinking federations the way
to go like we are north, let's all build
our own servers, let's put our servers in
our houses and and federate with
each other. And but
now I think it's
the perspective is a little screwed
because we are nerds.
Yes, we can do this, but we cannot expect
other people to do it.
And federation is great.
It's an improvement over the status quo.
But if we could migrate
the existing services that we use on the
Internet into a truly peer-to-peer
infrastructure, and this is even better
because then we don't need any servers to
run.
We don't need any service to maintain and
be even more resistant to censorship.
And we can just root around it.
And I don't know if you have seen the
just before my talk in the South Extra,
there was a talk about climate change
which enable you to
to to also put trust relationships
and computer networks in the privacy
friendly way.
So so these kind of new technologies
would be great to to enable all sorts
of new peer to peer applications, even if
you need to trust, like in the sharing
economy, like if you want to do some sort
of peer to peer uber or peer to peer
Airbnb, like, let's do it, please.
And I hope Breyers technology can help.
You may be doing it.
So we have
at the moment an Android application
that you can get on Google Play or better
asteroid right away and test
it out, play with it on Congress.
And if you want to meet me later here
next to the stage and then we go
somewhere and we can edit each other and
try how good it works
and to anticipate already a
question that we get a lot.
But I have I was like, where's your IRS
application?
And we would like to have some IRS
applications because one of our target
audience are journalists who need to
communicate securely with their sources.
And these people have iPhones all the
time. So we looked into
it. And so far it doesn't look good
because iPhone closes all applications
quite soon after you put them in the
background and you're not allowed to keep
TCAP connections open.
And we need to do this so you can get
messages.
So if you are an iOS developer
and you have some ideas how we can get
around this, please get in touch.
And the source code is, of course,
free software available for everybody to
use, and we're also
working on making it builds reproducibly,
which is very important because you need
to be able to verify that the source code
actually matches the binary or that we
ship. And you need to be able everybody
need to be able to verify that so nobody
can build any back doors inside.
So always a source, binary correspondence
and the latest versions mostly
build reproducibly, but there's still
some kinks to work out, unfortunately.
So I'm at the end of my
presentation.
Thank you very much for your attention
and I hope you have some questions.
That was awesome.
I beg your pardon,
questions, who has a question?
There's mikes left and right,
Internet signal
changes yet signal
has a message from the question from
the Internet.
Go ahead.
The Internet wants to know how it's
different from retros share and
doesn't have the traditional features or
some advantages of protocol.
Well, I'm not a retrocession expert, so I
can tell like to
take this with a grain of salt.
But as far as I know, Russia users
and infrastructure.
So it is relaying messages
between peers all the time, which would
burn the battery if used on mobile quite
a lot.
And it basically just does everything.
But it doesn't care as far as I know so
much about the metadata being leaked.
And also, as far as
I know, you cannot reduce
your share of other kinds of data
transports easily like like we do.
Thank you.
One sentence with a question mark at the
end of it.
Yeah, I would like to see to know
what are actually the difference with the
ring project. I've heard about the ring
project, which is also kind of
decentralized messaging services.
Actually, I had I follow a couple of
conference from the project and I saw
that a lot of feature were missing
because of the structure of it, the
centralized. You don't have the history.
You can, after all, device that are
synchronized together for all accounts
and these kind of things. So what is your
point of view on those kind of future?
Well, I also don't know the project, but
it's great to know that there is more of
these things happening. And I don't say
like use, Bryan, that's the only true of
like, let's build whatever works.
Right. And your point
about multiple devices is indeed
something also we have not solved,
because if you are in the peer to peer
network and you have two devices, you
need to consider the case where you go
online with one device, you make one
action in the application,
and then you go online in the other
device before it is able to sync this
information. And you make a conflicting
action like leaving a group
and posting a message.
So it looks like you left, but you're
still posting something and how how to
resolve this. Like we haven't solved it
yet.
OK, thank you
for four minutes. Question one sentence,
question mark. You mentioned iOS.
What are other ways that people can help,
Brian?
Well, there is lots of ways that people
can help Brayer because there's lots of
work to be done.
One thing that would be nice would be to
have a desktop client.
And essentially we just need the UI on
top of the libraries that we already
have. So this is something where people
can get started easily.
But we also have, of course, a bug
tracker and a feature tracker where
people can just say, hey, I want to
implement this and then we help you.
Signal angel, no.
Yes, yes, yes, go ahead.
OK. The Internet wants to know what
happens if an attacker gets hold of the
device. Is there some some kind of, like,
deniability or something?
Well, deniability is not one of
our design goals.
However,
it's an Android application.
And most people on Android, they don't
have a full disk encryption or anything
like that. So what we do
to improve the situation is to encrypt
all data that Brier stores in its
own database
with password curation
function, but based on the password.
So whenever you go online, you need first
to enter your password to a database.
And then there's also a panic
button feature, like when you have a
panic button app and you're like,
I don't know, the police is coming to
arrest you and you press the panic
button, then you can have Brierre
deleting the database or just locking out
so that the data address is at least
secure.
Thank you.
Two more questions, one left, one right,
red one starts when
you talk, how do
two beers find each other in
the network?
This is where hidden services help us
because the TOYIN Service has
has a unique address, which is
essentially its public key, and there is
directory service in the network.
When you come online, you get listed
there and this is how they find you.
So you don't need to use any any firewall
punching any network of the stuff.
You you just go into one network and you
say, I want to connect to this in
service. And if they're online, they will
respond. And if not, not.
Thank you.
Last question from my left here,
so do you use Bluetooth
currently to connect?
But recently there was discovered some
important vulnerabilities regarding
Bluetooth, which makes it advisable to
use in androids.
So how do you handle that?
Yeah, that's unfortunate.
And Bluetooth is not only has lots
of security problems, but it's also very
flaky and difficult to work with.
So our response to that was to
be more conservative on on how long
Bluetooth needs to be enabled.
So we try to reduce the time.
And it's also possible that you don't
need to use it at all.
There are still some improvements.
We do. And also we one of our
largest contributors, he implemented
a prototype of Wi-Fi direct plugin
where two phones can connect to
each other directly with Wi-Fi without
being in any sort of access point.
And so maybe when we're lucky
in the future, we don't need to use
Bluetooth at all.
OK,
let's have a big fight.
There are still seven and I have to cut
off, I have to cut off.
I'm sorry. The next talk is going to be
Max James is going to be packed like hell
and we got to get the people in and out
first. So I have to cut off here.
I'm awfully sorry.